Human pluripotent stem cells (PSCs), including human embryonic stem cells and induced pluripotent stem cells, are promising cell sources in regenerating pancreatic islets through in vitro directed differentiation. Recent progress in this research field has made it possible to generate glucose-responsive pancreatic islet cells from PSCs. Single-cell RNA sequencing techniques have been applied to analyze PSC-derived endocrine beta-cells, which are then compared with human islets. This has led to the identification of novel signaling pathways and molecules involved in lineage commitment during pancreatic differentiation and maturation processes. Single-cell transcriptomics are also used to construct a detailed map of in vivo endocrine differentiation of developing mouse embryos to study pancreatic islet development. Mimicking those occurring in vivo, it was reported that differentiating PSCs can generate similar islet cell structures, while metabolomics analysis highlighted key components involved in PSC-derived pancreatic islet cell function, providing information for the improvement of in vitro pancreatic maturation procedures. In addition, cell transplantation into diabetic animal models, together with the cell delivery system, is studied to ensure the therapeutic potentials of PSC-derived pancreatic islet cells. Combined with gene-editing technology, the engineered mutation-corrected PSC lines originated from diabetes patients could be differentiated into functional pancreatic islet cells, suggesting possible autologous cell therapy in the future. These PSC-derived pancreatic islet cells are a potential tool for studies of disease modeling and drug testing. Herein, we outlined the directed differentiation procedures of PSC-derived pancreatic islet cells, novel findings through transcriptome and metabolome studies, and recent progress in disease modeling. Pancreatic islet cell therapy is a promising treatment for diabetes mellitus; however, it is hampered by the persistent shortage of donor islets . Human pIslets of Langerhans, commonly referred to as pancreatic islets, are derived from the definitive endoderm. The endoderm then folds to form the primitive gut tube, followed by region specification and organ-specific bud formation, subsequently giving rise to various respiratory, digestive organs, including the dorsal and ventral pancreas. Pancreatic buds, where the pancreatic progenitors originate, are marked by pancreatic and duodenal homeobox 1 (PDX1), a gene required for pancreatic growth. Developmental processes continue with an expansion of these pancreatic progenitors followed by fate divergence into exocrine and endocrine progenitors. The morphogenetic processes and expression profiles of key lineage-specific genes that contributed to pancreatic development in vertebrates were studied, and this knowledge was applied to in vitro directed differentiation of pancreatic islet cells from PSCs –6.Stepwise pancreatic differentiation protocols from PSCs are established by mimicking the in vivo pancreatic development processes. PSCs are sequentially differentiated into definitive endoderm (DE), primitive gut tube (PG), pancreatic progenitor (PP), endocrine progenitor (EP), then into hormone-expressing endocrine cells (EC). The in vitro differentiation procedures utilize the inhibition or activation of WNT, transforming growth factor-β (TGF-β) superfamily signaling pathways, such as Activin, Nodal, and Bone Morphogenic Protein (BMP), retinoic acid (RA), and protein kinase C (PKC) signaling Fig. a. CombinWnt3 during mice embryogenesis resulted in defective primitive streak formation [Nodal-Smad2 mutant mice [DE differentiation from PSCs involves the activation of Activin/Nodal and WNT signaling. Inactivation of ormation . The endant mice . This knant mice . D’Amourant mice . They laant mice . In consant mice .Shh is expressed along the gut tube but is absent in the pancreatic endoderm. The removal of notochord results in an induction of Shh expression in the pancreas and a loss of pancreatic gene expression, suggesting that the repression of Shh is permissive for early pancreatic development [Fgf10 is expressed in the mesenchyme adjacent to the early dorsal and ventral pancreatic epithelial buds. Upon deletion of Fgf10 in mouse embryos, subsequent growth, differentiation, and branching morphogenesis of the pancreatic epithelium are arrested [Fgf10-expressing transgenic mice exhibited cell proliferation of the pancreatic epithelium [N-(aminoethyl-aminocaproyl-dihydrocinnamoyl) cyclopamine (KAAD-cyclopamine), and FGF10 resulted in PG induction [PG formed after the establishment of DE, coincident with a transition from a two-dimensional cell sheet into a three-dimensional tube-like structure . Fibroblelopment , 16. Fgfarrested . On the ithelium . PSC-dernduction .PDX1 expression level [PDX1 expressing cells, suggesting that inhibition of BMP signaling potentiates pancreatic differentiation and suppresses hepatic and intestinal differentiation [NEUROG3) expression defines the pancreatic EP cells, which later differentiate into ECs [NEUROG3-expressing cells [Signaling pathways involving RA, PKC, BMP signaling, and others were reported to be potent in inducing PP and EP in vitro. Jiang et al. reported that the addition of all-trans retinoic acid contributed to the increased PDX1-positive cell population . Exogenoon level . Shahjalntiation . A high ntiation , 6, NK6 ntiation . Even wintiation . KGF incntiation . Neurogeinto ECs . Continung cells . A smallng cells .INS-expressing cells [Neurog3 that plays a key role in determining the endocrine fate [MAF bZIP transcription factor A (MAFA), a critical beta-cell maturation marker gene [N-acetyl cysteine -positive EC cells. Treatment of the human fetal pancreatic islet cells with Nicotinamide (the amide form of vitamin B3) resulted in increased DNA content, thereby suggesting the expansion of the pancreatic progenitor cells, as DNA synthesis was stimulated only in the nonhormone-expressing cells . Nicotinng cells . Thyroidng cells . T3 promng cells . In miceng cells . In contine fate . From a ine fate . Monoamiine fate . Rezaniaker gene . They prear MAFA ), Alk5i N-acetyl cysteine, Alk5i II, and T3 treatment, Rezania et al. successfully increased the MAFA transcription levels in ECs. The pancreatic islet cells generated from PSCs expressed the key markers of mature pancreatic beta-cells, including MAFA. The PSC-derived pancreatic beta-cells displayed improved glucose-stimulated insulin secretion (GSIS) [Among all the above growth factors and small molecules used during pancreatic differentiation, the combination, dosage, and exposure time of these components are important to obtain functional hormonal-expressing ECs. Table n (GSIS) . Velazcon (GSIS) .Table 2Present research progress has shown that regeneration of pancreatic islets using PSCs is not an unreachable goal. There are remaining tasks in investigating the similarity and differences between PSC-derived ECs and human islets, not only with regard to the cell culture microenvironment and molecular characteristics, as well as long-term maintenance of the function of the PSC-derived ECs. Recent progress regarding the cell culture microenvironment, together with transcriptome and metabolome profiles of PSC-derived ECs resulted from the differentiation procedure above, will be discussed in the later sections.Apart from the optimization of medium components, several studies highlighted that cell culture system, such as adherent culture, culture in suspension, or reaggregation culture, during differentiation could affect pancreatic differentiation. Directed differentiation was initially done using adherent culture systems. In an attempt to overcome surface-area constraints, achieve manufacturing-scale culture, and prepare enough cells for transplantation, suspension procedures were proposed , 40. FurThe state of the cytoskeleton was reported to affect the expression levels of transcription factors for endocrine differentiation. PSCs cultured under adherent conditions were reported to yield a decreased differentiation efficiency into ECs. This issue was overcome by treatment with a cytoskeletal depolymerizer latrunculin A. Under adherent cultures of three PSC cell lines, latrunculin A treatment yielded islet cells exhibiting key markers of mature pancreatic cells and dynamic insulin secretion with first- and second-phase . A detaiINS, NKX6.1, and other beta-cell markers; (2) polyhormonal alpha-like cells that express GCG, Aristaless-related homeobox (ARX), and INS; (3) enterochromaffin cells and endocrine cell types expressing CHGA, Tryptophan hydroxylase 1 (TPH1), LIM homeobox transcription factor 1 alpha (LMX1A), and Solute carrier family 18 member A1 (SLC18A1); and (4) SRY-Box Transcription Factor 9-(SOX9)-expressing non-ECs (a pancreatic duct marker of exocrine cells). A surface marker of PSC-derived beta-cells, CD49 antigen-like family member A (CD49a), was identified, and pure PSC-derived beta-cell clusters were generated [MNX). MNX-positive cells will eventually express NKX6.1 and E-twenty-six (ETS) transcription factor, Fifth Ewing variant (FEV). FEV expression precedes LIM homeobox 1 (ISL1) in EP cells that mark cells on the beta-cell pathway. MNX-negative cells in turn give rise to the FEV-negative ISL1-positive cell population which further progress into ARX- and INS-positive cells, attesting to the polyhormonal characteristics of the cells [Given that significant progress has been made in directed differentiation of pancreatic islet cells from PSCs, recent investigations utilized transcriptome sequencing and metabolome analysis of the differentiating PSCs to characterize their cellular identity. Compared to the bulk RNA sequencing result of PSC-derived INS-expressing cells before aggregation, reaggregated PSC-derived INS-expressing cell clusters showed a higher degree of correlation with beta-cells isolated from adult human islets . From sienerated . In vitrhe cells . Sharon he cells .In a recent report, Helman et al. performed a metabolic analysis of PSC-derived beta-cells, focusing specifically on their glucose responsiveness. The authors investigated the possibility that sensing environmental nutrients by mechanistic target of rapamycin complex 1 (mTORC1) contributes to islet cell maturation. They found that the mTORC1 pathway was strongly activated in fetal beta-cells, while adult human beta-cells showed low mTORC1 activity. The activated mTORC1 was responsive to glucose and amino acids. By culturing PSC-derived beta-cells under an amino acid-rich, but not glucose-rich medium, activation of the mTORC1 signaling pathway was observed, evidencing their similarity with fetal beta-cells. Inhibition of the mTORC1 signaling with an mTOR inhibitor, Torin1, improved glucose-responsive insulin secretion of PSC-derived beta-cells . The finFunctional islets derived from PSCs can be analyzed using scRNA-seq to determine novel signaling pathways and lineage commitment of PSCs during pancreatic differentiation and maturation. At the same time, metabolome studies enable us to acquire information on PSC-derived islet cell function. These approaches will provide us a clearer picture to understand the specific molecules involved and the exact timing for differentiation cues, facilitating the future development of directed differentiation to generate functional pancreatic islets from the PSCs.As islet transplantation progressed over the past decades, these following aspects are reported to be ideal for transplant procedures: ready access to oxygen, glucose and insulin delivery, minimal procedural risk, long-term functionality and low inflammatory reaction, and monitoring of islet after transplantation. To reduce substantial islet cell loss and graft inflammation, alternative transplantation sites, cell sources, and encapsulation technologies were studied to improve islet transplantation , 52.PSC-derived pancreatic beta-cells generated in vitro via directed differentiation mentioned above, as an alternative cell source, were transplanted into the immunocompromised diabetic mouse models to verify their function under in vivo environment , 20. ImmThe functionality of the engrafted PSC-derived pancreatic islet cells can be confirmed on the condition that transplanted cells exhibited a high population of INS- or other mature beta-cell marker-expressing cells , 42, 44.NKX6.1 and INS compared to control individual [PSC technology is opening the door to study specific disease mechanisms and therapies via disease modeling and drug testing as the generation of PSCs using somatic cells from patients has become possible . There adividual , 61.Recent progress was made through optimization of the differentiation procedures and application of gene-editing technology, the CRISPR-Cas9 system, using PSCs from diabetic patients. Unlike type 1 diabetic patients, these patients carry specific gene mutations that cause diabetes , 63. BalGeneration of functional pancreatic islet cells using PSCs had become possible based on the substantial progress made over the past years. Also, transplanted PSC-derived islet cells have shown the ability to normalize pre-existing hyperglycemia in mice. Follow-up research in the next decade would likely be focused more on molecular mechanisms of PSC-derived islet cells, delivery systems for transplantation, and experimental disease treatment involving the application of patient PSC-derived islet cells for therapeutic efficacy and safety considerations.


Multiple organ dysfunction or even failure after sepsis or trauma is due to a dysregulated host response. Currently, besides  source control  and administration of antimicrobial drugs, therapeutic approaches are limited to supportive care. Advances in our understanding of the key pathophysiological pathways involved in the excessive inflammation triggered by trauma, sepsis and/or ischemia-reperfusion have had limited impact. The 28 article in this Research Topic focus on the molecular mechanisms behind (hyper) inflammation after sepsis or trauma, with special emphasis on preclinical and translational studies that target potential organ-protective and/or -resuscitative therapeutic strategies. Most studies report rodent models of trauma and elective surgery (three articles), non-microbial hyper-inflammation induced with endotoxin exposure  and chemical pancreatitis (one article), and cecal ligation and puncture-induced sepsis (six articles). Additional papers summarize investigations of human material (six articles) or fully-resuscitated large animal models (two articles). These article are complimented by four reviews and a commentary.Velagapudi et al. investigate the pathophysiology of post-traumatic/surgical delirium. The authors investigated the effect of murine limb trauma on post-operative behavior  and neuroinflammation and blood-brain barrier integrity (by using light-sheet microscopy). Post-surgery behavior showed impairment, in parallel with reduced microglial ramification and overall cell volume impaired hippocampal astrocytic-tight junctions. Wall et al. characterized the mechanisms underlying post-traumatic cardiac dysfunction in mice undergoing soft tissue trauma and bone fracture followed by hemorrhage. Despite resuscitation, stroke volume remained at 25% of baseline values, which was associated with leukocyte infiltration and ultrastructural sarcomere and mitochondriadisorganization, leading to increased serum levels of heart fatty acid-binding protein and troponin I. The authors concluded that mitochondria-driven apoptosis may be a target to prevent irreversible post-traumatic cardiac injury. In a rat model of abdominal surgery, Bangash et al. further clarified the anti-inflammatory properties of the β2-agonist dopexamine. Ileal intravital microscopy demonstrated that attenuated leukocyte-endothelial adhesion in post-capillary venules while neither arteriolar diameter, functional capillary density nor systemic hemodynamics nor lactic acidosis were affected compared to control animals. Interestingly, despite comparable effects on the intestinal microcirculation, high dose dopexamine only, in contrast to the pure β2-agonist salbutamol, also attenuated surgery-related increase in serum creatinine.Wepler et al. compared wildtype (GR+/+) mice with animals with impaired GR dimerization (GRdim/dim) under conditions of full intensive care support . GRdim/dim mice presented with more severe shock and aggravated acute lung injury, which coincide with increased tissue osteopontin expression. Ng et al. provided evidence for the anti-inflammatory mechanisms of acute, binge-drinking-like alcohol intoxication: alcohol exposure attenuated the inflammatory response to LPS in vivo, ultimately improving survival, which was associated with increased gene expression of the Glucocorticoid-Induced Leucine Zipper (GILZ), a key molecule acting via non-canonical GR activation. Inhibition of ethanol metabolism enhanced this effect, and interestingly, the higher molecular-weight short-chain alcohols propanol and isopropanol were even more potent than ethanol.Although clearly distinct from polymicrobial sepsis, endotoxin (LPS) challenge and chemically-induced pancreatitis are often used to model hyperinflammation, and indeed, sepsis due to their reproducibility and the subsequent organ failure that mimics that of sepsis. Two studies addressed the potential role of the glucocorticoid receptor (GR) in LPS-induced organ dysfunction. Dayang et al. provided new evidence relating to the complex organ- and organ- and microvascular bed-specific LPS-induced expression of the endothelial adhesion molecules E-selectin and VCAM-1. The authors showed in LPS-challenged mice that the renal microvascular endothelium expressed various E-selectin and VCAM-1 subpopulations, i.e., E-selectin−/VCAM-1−, E-selectin+/VCAM-1−, E-selectin+/VCAM-1+, and E-selectin−/VCAM-1+. The formation of subpopulations was a common response of endothelial cells to LPS challenge. FACS analysis demonstrated that the +/+ subpopulation expressed the highest cytokine and chemokine response, which was mainly TLR4-mediated. Activation of NF-κB and p38 MAPK were key signaling events in the formation of this +/+subpopulation. The translational value of these murine data was highlighted by the recapitulation of these effects in LPS-exposed HUVEC and human lung microvascular endothelial cells.Lehner et al. The central-acting cholinergic agonist galanthine suppressed the systemic TNFα response to endotoxemia in mice, and this effect was suppressed by both local genetic ablation of acetylcholine release and vagotomy. In contrast, local and selective activation of the M1 muscarinic acetylcholine receptor (M1 mAChR) with the allosteric agonist benzyl quinolone carboxylic acid also suppressed the serum TNFα levels, thereby ultimately improving survival; these beneficial effects were again suppressed in M1 mAChR-ko mice. Overall, these data suggest a bidirectional relationship between brain cholinergic signaling and the systemic inflammatory response.The role of the forebrain cholinergic system for the systemic immune response was addressed by Deng et al. investigated the potential of targeting citrullinated histone H3 (CitH3) to neutralize neutrophil extracellular traps. When administered simultaneously with a lethal dose of LPS, anti-CitH3 monoclonal antibodies prevented HUVEC damage in vitro and attenuated ALI in vivo via inhibition of the inflammatory response, thereby ultimately reducing mortality. The therapeutic potential of the anti-inflammatory xanthone glucoside mangiferin was studied by Yang et al. in mice with LPS/galactosamine-induced acute liver failure. Pre-treatment with magiferin inhibited hepatic TNF-α production, decreased serum aminotransferase activities, and improved survival. This beneficial effect was abolished by Kupffer cell deletion, and at least in part, related to increased heme oxygenase-1 expression.Two studies focussed on possible therapeutic interventions. in vivo and taurocholate-induced pancreatic acinar cell line in vitro were used to study the roll of the Toll-like receptor 3 (TLR3) ligand polyI:C by Huang et al. PolyI:C is a double-stranded RNA mimic that can act as an immune stimulant by triggering type I interferon (IFN) production and downstream IFN-α/β receptor (IFNAR)-dependent signaling, and pre-treatment inhibited chemotaxis and ROS production. This was abolished in IFN-β- and IFNAR-ko mice.Models of caerulein-induced acute pancreatitis Minimum Quality Threshold in Pre-Clinical Sepsis Studies” (MQTiPSS) guidelines, thus allowing for easier inter-laboratory comparability.CLP is one of the most frequently used models of polymicrobial sepsis. While three studies in this special issue were designed to further character molecular pathways of sepsis pathophysiology, others evaluated the efficacy of specific therapeutic interventions. Most of the studies have the merit of integrating the “Li et al. addressed the role of the switch of macrophage phenotype from the pro-inflammatory M1 state to the M2 repair  state in septic AKI. Coculture of human M1 macrophages with proximal tubular (HK-2) cells revealed that Colony Stimulating Factor 2 (Csf2) was the most up-regulated protein, and post-CLP injection of a Csf2 antibody attenuated kidney M1-M2 macrophage transition via p-STAT5 signaling, suppressed tubular proliferation, and increased mortality.Kikuchi et al. Mice with genetic deletion of the catalytic α1 isoform (AMPKα1) had higher systemic cytokine levels, liver and lung inflammation and injury, and in particular, more severe hepatic mitochondrial damage and mortality. These deleterious effects were even more pronounced in male animals, suggesting that AMPK-dependent liver metabolic (dys) function is sex-dependent.The role of AMP-activated protein kinase (AMPK) was investigated in murine CLP-induced sepsis by Skiretzki et al. further characterized the translational value of an established, “humanized” murine model of CLP-induced sepsis. Animals were stratified as “predicted-to-die (P-DIE)” or “predicted-to-survive (P-SUR),” and blood, bone marrow and spleen were collected for cytokine and chemokines as well as CD-80 and HLA-DR expression. TNFα, IL-6, IL-10, IL-8/KC-, and MCP-1-levels were several-fold higher in the P-DIE group. The study nicely showed that humanized mice reflect human immune responses.O'Riordan et al. When administered early (1 h) after the CLP-procedure, the BTK inhibitors attenuated sepsis-induced systolic dysfunction and reduced systemic and tissue NF-κB and NLRP3 inflammasome activation. This is clinically relevant as both BTK inhibitors are already approved for the treatment of chronic lymphatic leukemia (CLL), and acalabrutinib has recently been reported to attenuate systemic inflammation in a small cohort of patients with COVID-19 . However, despite promising data on ibrutinib during lipoteichoic acid-induced pulmonary inflammation as well as and ceftriaxone-treated pneumococcal pneumonia  inhibitors ibrutinib and acalabrutinib for septic cardiomyopathy and AKI was investigated by ed early  h after neumonia , and in Al Zoubi et al.). This study is of particular importance, since it sheds light on one of the most frequently occurring chronic co-morbidities observed in patients with sepsis and/or after trauma, which is well-known to worsen the patient's outcome. In good agreement with these clinical observations, T2DM aggravated sepsis-related (organ) dysfunction associated with sepsis, which was comparably mitigated by both tested drugs. This effect of linagliptin was associated with reductions of NF-κB activation, iNOS expression and serum levels of pro-inflammatory cytokines.Another approved drug, the oral antidiabetic linagliptin, was compared with the selective IkB kinase (IKK) inhibitor (IKK-16), with respect to its effects on septic cardiomyopathy as well as kidney and liver injury in murine high fat diet-induced type 2 diabetes mellitus (T2DM)  CLP-induced sepsis focussing on dynamic changes in monocyte and macrophage subsets. This double-hit model has the possibility of replicating the frequently occurring similar sequence in critically ill patients, i.e., an initial polytrauma is complicated by consecutive sepsis, and furthermore, allows investigating common “final routes” of these two pathological entities. Both pro-inflammatory monocytes and macrophages significantly increased in blood, lungs and bronchoalveolar lavage fluid (BALF) at the expense of tissue repairing macrophages, which coincided with higher levels of TNF-α, MCP-1, and RAGE. Uteroglobin neutralization further aggravated this pro-inflammatory response, and subsequently, lung damage, thereby highlighting intrinsic anti-inflammatory signaling role of this protein.Finally, Horst et al. made use of these facts for the characterization of time-dependent dynamics of the inflammatory response in the blood, the femur fracture hematoma, and muscle samples of polytraumatized  swine in comparison to animals with femur fracture alone (monotrauma). The severity of the polytrauma substantially inhibited the local generation of proinflammatory and angiogenetic mediators, suggesting that these systemic trauma-related changes of the local immunologic milieu might explain the delayed bone repair in PT patients. The same porcine PT model was used by Lackner et al. to address the role of midkine levels for post-traumatic cardiac dysfunction. The porcine data were complemented by (i) the measurement of midkine blood levels in PT patients (ISS ≥ 16), and (ii) the functional assessment of human cardiomyocytes incubated with midkine. In PT patients, midkine levels were several-fold higher than in healthy volunteers, while in vitro midkine exposure of cardiomyocytes altered cell Ca2+ handling and reduced maximum mitochondrial O2 consumption.Despite the substantial demand for personnel, infrastructure and consumables as well as the often lacking test kits for the species involved, large animal (in particular porcine) models have the advantages (i) to allow for integration of standard ICU procedures into the experimental design, and (ii) to study an immunological environment that is closer to the human situation than any other species (except for non-human primates). Le, Matzaraki et al.; Le, Chu et al.) that aimed at further characterizing the major determinants of leukocyte and/or endothelium responses to bacterial sepsis. In the first study  expression quantitative trait loci (eQTL) data from the largest whole-blood eQTL database, cytokine QTLs from pathogen-stimulated peripheral blood mononuclear cells (PBMC), blood transcriptome data from pneumoniae-derived sepsis patients, and transcriptome data from pathogen-stimulated PBMC were integrated and found increased adherence-junction gene expression. The authors concluded that their approach provided evidence for genetically determined variability in both leucocyte and endothelial responses, which may contribute to explaining sepsis heterogeneity. In their second study , the authors' group investigated transcriptomic responses of human leukocytes and endothelial cells to Gram negative-bacteria, Gram positive-bacteria, and fungi. While whole pathogen lysates strongly activated leukocytes but not endothelial cells, the mutual leukocyte response to pathogens resulted in endothelial activation. Exposure of endothelial cells to leukocyte mediators activated endothelial cells at both transcription and protein levels, and revealed IL-1, TNF-α, and IFN as important drivers of endothelial activation.Sophisticated genome/transcriptome analyses were used by Le et al. in two studies . From a total of nearly 500 blunt trauma survivors (ISS > 20) a subgroup of patients injured during daytime (“mDay”) was compared to patients injured at nighttime (“mNight”) in order to investigate the impact on 32 inflammatory mediators using Dynamic Network Analysis (DyNA) and Dynamic Bayesian Network (DyBN) inference. Both hospital and ICU length of stay were longer in the mNight patients, which coincided with higher IL-17A but lower MIP-1α, IL-7, IL-15, GM-CSF, and sST2 levels; DyBN yielded cortisol and sST2 as the major upstream determinants upstream of TGF-β1, chemokines, and Th17/protective mediators in both groups, with IL-6 being an additional downstream node in the mNight group only.Another study was dedicated to investigate the potential role of circadian rhythm and/or diurnal variations on the systemic inflammatory response, and ultimately outcome in patients with trauma   removal on mortality. Both HSP70 and HMGB1 clearance rates were good predictors of mortality, and high HSP70 clearance coincided with the level of HLA-DR expression. Based on these findings the authors cautioned the use of CVVH in AKI patients with sepsis merely for the removal of inflammatory mediators in the absence of any other indication for this therapeutic measure.In patients with septic AKI undergoing continuous veno–venous hemofiltration (CVVH), Neu et al. present a study on the feasibility of a direct, non-invasive, bedside measurement of skin mitochondrial oxygen tension (mitoPO2) with a new commercially available device that makes use of the “in vivo protoporphyrin IX-triplet state lifetime technique (PpIX-TSLT).” In 40 patients a three-step measurement was performed after enriching the clavipectoral triangle with 5-aminolevulinic acid, which comprised assessment of baseline values, evaluation of the effect of a local pressure to transitorily stop microcirculatory blood flow, and a second control value. The recorded data allowed calculating average and maximum mitoVO2 at these three time points. The technique was reproducible, easy, and safe; potential tissue edema as assessed by bioimpedance resulted in lower mitochondrial oxygen tension.Finally, Cheng et al. discuss the possible role of Parkinson disease protein 7 (Park 7), a well-established regulator of reactive oxygen species (ROS) release through interaction with p47phox, a subunit of NADPH oxidase. Among their various functions, ROS initiate TLR to activate macrophages. Consequently, Park 7 may be a novel therapeutic target to reverse sepsis-related immunosuppression. Morrow et al. discuss septic immune paralysis in the light of the markedly decreased T cell formation of pro-inflammatory cytokines. Since targeting lymphocyte survival did not find its way into clinical practice, cytokines with a more global immune effect may represent alternative therapeutic targets. The authors discuss the possible impact of the interleukin (IL)-17, IL-27, and IL-33 based on data from patient serum and murine models of peritonitis and pneumonia.Two articles reviewed potential new pathways (and consecutive therapeutic targets) of sepsis-related immune paralysis. Denning et al. review the complex interplay of host response to pathogens via interaction of pathogen-associated molecular patterns (PAMPs) and pattern recognition receptors (PRRs) and damage-associated molecular patterns (DAMPs), and Neutrophil extracellular traps (NETs). Examples of DAMPs are extracellular cold-inducible RNA-binding protein (eCIRP), high mobility group box 1 (HMGB1), histones, and adenosine triphosphate (ATP). DAMPs are released by inflammasome activation or passively from dead cells. NETs are mixtures of extracellular DNA with histones, myeloperoxidase, and elastase, all released during inflammation. Although NETs clearly contribute to pathogen clearance, their excessive formation causes tissue damage.Cheng et al. discuss the potential of mesenchymal stem cells (MSCs) in the treatment of sepsis. Highlighting the possible undesired side effects, the authors also emphasize the potential of extracellular vesicles (EVs) derived from MSCs (MSC-EVs). These MSC-EVs appear to exert a therapeutic benefit similar to MSCs in protecting against sepsis-induced organ dysfunction by delivering RNAs and proteins to target cells, while at the same time being devoid of major MSC side effects. In addition, MSC-EVs provide some practical advantages over their parent MSCs.Based on their multiple and ubiquitous properties, Kesselmeier and Scherag comment on the recently popularized “adaptive clinical trials” discussing a recent article in this journal by Talisa et al. (Finally, a et al. . The autIn summary, the Research Topic entitled provides a broad and detailed overview of new molecular and mechanistic avenues for the management of sepsis- and trauma-related multiple organ dysfunction, and represents a major contribution to translational research in the field.All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Glycosylation, being the most abundant post-translational modification, plays a profound role affecting expression, localization and function of proteins and macromolecules in immune response to infection. Presented are the findings of a transcriptomic analysis performed using high-throughput functional genomics data from public repository to examine the altered transcription of the human glycosylation machinery in response to SARS-CoV-2 stimulus and infection. In addition to the conventional in silico functional enrichment analysis methods we also present results from the manual analysis of biomedical literature databases to bring about the biological significance of glycans and glycan-binding proteins in modulating the host immune response during SARS-CoV-2 infection. Our analysis revealed key immunomodulatory lectins, proteoglycans and glycan epitopes implicated in exerting both negative and positive downstream inflammatory signaling pathways, in addition to its vital role as adhesion receptors for SARS-CoV-2 pathogen. A hypothetical correlation of the differentially expressed human glycogenes with the altered host inflammatory response and the cytokine storm-generated in response to SARS-CoV-2 pathogen is proposed. These markers can provide novel insights into the diverse roles and functioning of glycosylation pathways modulated by SARS-CoV-2, provide avenues of stratification, treatment, and targeted approaches for COVID-19 immunity and other viral infectious agents. Of the four major classes of biomolecules , the glycans conjugated to proteins and lipids provide a ubiquitous biological interface at cell surfaces, where they are instrumental in intermolecular and cell–cell recognition events that define and control cell interactions and functions . Indeed,As the significance of SARS-CoV-2 and the associated risks posed more evident, diverse structural, biochemical and genome-wide screening approaches have been undertaken to identify and elucidate host factors involved in SARS-CoV-2 infection ,5. StudiModulation of host glycosylation machinery is a fundamental molecular mechanism leveraged by biological agents for eliciting pathogen specific immunity . Variatin ≥ 3) and organoids treated with SARS-CoV-2 virus (n ≥ 3). Datasets without gene annotation were excluded.Gene Expression Omnibus (GEO) was queried using the search terms “(COVID-19 OR SARS-COV-2) AND gse[entry type]”, with filtering criteria “Expression profiling by HTS” and the organism “Homo sapiens” applied. Datasets included gene expression data generated from ex-vivo and autopsy samples from COVID-19 subjects as well as human cell lines (https://www.genenames.org/) and further cross-validating the list using the Gene group reports from HGNC for completion. Details of the enzymatic reactions for the glycosyltransferase and glycosidase enzymes was enriched by manually curating the reactions from the BRENDA enzyme database (https://www.brenda-enzymes.org/index.php) and ExPASy bioinformatics resource portal (https://www.expasy.org/). For interactions where the reaction information is not available the interactions were curated manually from PubMed sources.Glycosylation machinery gene set  was compiled from the GlycoGAIT database . Summarihttp://software.broadinstitute.org/cancer/software/genepattern/) [https://usegalaxy.org/) [https://reactome.org/) [http://cpdb.molgen.mpg.de/) [http://www.cytoscape.org/) [GenePattern (attern/)  and Galaxy.org/)  were utixy.org/) . Using txy.org/)  availablxy.org/)  detailedme.org/) . The indmpg.de/)  was usedpe.org/) .p-value) significant genes with adjusted p value ≤ 0.1 and uncorrected p value ≤ 0.05 were identified for each data points , with the filter criteria of having at least three minimum samples for both control and SARS-CoV-2 treated/infected conditions . From tha points . Using ta points , DEGs fo samples . Data an samples . Moreove samples . Higher  samples .For focused analysis on glycogenes, a stringent log2 fold change cut-off values ≤ −0.58 and ≥0.58 (fold change ≥ 1.5-fold) was performed. Detailed gene set enrichment analysis of the resulting DEGs using the g:Profiler toolset, highlighted specific cellular processes such as the glycosaminoglycan, proteoglycan, glycolipid, N-glycan and O-glycan metabolic processes as the maximum represented biological categories . SimilarA genome-wide overview analysis from the Reactome database highlighted metabolic pathways associated with glycosylation modifications and additionally a number of immune related pathways including the immune-regulatory interaction between lymphoid and nonlymphoid cells, majorly represented by the DEGs transcribing for the lectin proteins . Among tLectins were the second category of maximum represented DEGs identified from the SARS-CoV-2 infected biopsy samples, cell lines and organoid relevant to the respiratory tract tissues . The C-t+ T-cell responses. Moreover, serglycin proteoglycan with sulfated glycosaminoglycans of either heparin, heparan sulfate or chondroitin sulfate types attached to it is a major regulator of the mast cell secretory granule homeostasis [Significant DEGs, grouped under the glycosylation associated cellular function pathways, were also manually analyzed for the association with human pathogenic viruses and immune system in order to understand the physiological relevance in response to SARS-CoV-2 infection from the biological samples (biopsies and cell lines) representing the upper respiratory tract . Manual eostasis . Recent eostasis . Given teostasis , it willx/a):  antigens, may suggest the intriguing possibility of expression of these antigens in the upper and lower tract of airway epithelium. The role of Sd(a) and sLex/a antigens as glycan ligands in regulating the adhesion and infection of airway epithelium by human and avian influenza viral strains is well reported , involved in the synthesis of Sd(a):  antigen and the fucosyltransferases as well as α-2,3-sialyltransferases involved in the synthesis of Sialyl Lewis x/a  were identified. Among them the mannose binding lectin serine protease 2 (MASP-2) has also been implicated in the altered lectin complement pathway resulting in accelerated inflammatory responses and lung damages involved in COVID-19 pathogenesis . Few othThe downregulated DEGs primarily represent the biological processes involved in glycan precursor biosynthetic pathways such as the N-glycan precursor biosynthetic processes, O-linked biosynthetic process, GPI-anchor biosynthesis as well as fucose, mannose and galactose metabolism . DefectiSimilar to the strategies previously applied for curbing the spread of viral infections, current research efforts are directed towards the development of therapeutic antibodies and vaccines for effective COVID-19 treatment ,45. KineGlycan binding proteins (GBPs) and the glycoconjugate structures play a crucial modulatory function in regulating the host immune responses under diverse inflammatory diseases . In caseIncreased expression pattern of major fucosyltransferases across the nasopharyngeal and lung samples as well as the cell lines may indicate a tendency of the SARS-CoV-2 infection to augment the inflammatory response by increasing the expression of glycan epitopes such as blood group antigens and Lewis X antigens that regulate the immune cell attraction to infected tissues ,68,69. Tx antigens and the increased expression of B4GALNT2 is an adaptive mechanism to reduce the severity of the infection.Based on these findings we hypothesize that SARS-CoV-2 infection results in the increased expression of α-2,3 and α-2,8 linked sialic acid structures in the human respiratory tract tissues aiding viral replication as observed in other similar avian viruses . SimilarGene expression pattern and the induced network model analysis results of the inflammatory CLECs and the anti-inflammatory SIGLECs mentioned in the current report is in alignment with the clinical phenotype of cytokine storm, neutrophil extracellular trap formation as well as the functional exhaustion of lymphocytes reported in severe cases of COVID-19 patients ,49,78,79In the current study, results from the gene expression pattern are largely influenced by the nasopharyngeal swab samples. Since the nasopharyngeal swab samples represent a collection of diverse epithelial and immune cell types, cell type-specific analysis is essential to delineate the diverse inflammatory and anti-inflammatory functions of these glycogenes. Further analysis of the inflammatory pathways in conjunction with the experimental validation of the immune regulatory lectins should provide greater insights into the molecular mechanisms underlying compromised innate immune response in severe cases of COVID-19 patients . LectinsThe current transcriptomic based study provides meaningful insights into the nature of gene expression alteration in glycosylation enzymes, proteoglycans, lectins and potential glycan markers that can be selected for targeted experiments to understand the immunomodulatory functions underlying SARS-CoV-2 infection. A list of potential CLECs, SIGLECs and Galectin lectins have been highlighted in the current research, which can be experimentally evaluated to modulate the cytokine storm or the lymphopenia pathology reported in COVID-19 subjects.


The novel coronavirus disease (COVID-19) pandemic is rapidly expanding across the world,with more than 60,000 new cases each day as of late March 2020. Healthcare workers arestruggling to provide the best care for patients with proven or suspected COVID-19.Approaches for clinical care vary widely between countries and regions, and new insightsare acquired rapidly. This includes the use of available imaging techniques.American Journal of Tropical Medicine and Hygiene,Chaisith and others1 report a case ofCOVID-19 from Bangkok, Thailand, recovering with only supportive care.1 The case not only highlights the importanceof early quarantining and repeated virologic testing of suspected COVID-19 patients butalso demonstrates well that abnormalities on the chest X-ray can precede a positive severeacute respiratory syndrome coronavirus-2 reverse transcriptase polymerase chain reactionresult from nasopharyngeal or throat swabs. Furthermore, Dr. Chaisith and others1 compared lung images from chest X-ray, chestcomputed tomography (CT) scan, and lung ultrasound (LUS) obtained later in the course ofthe disease.In this issue of the 2In COVID-19, chest X-ray typically shows nonspecific multi-lobar infiltrates or pulmonaryinfiltration that can rapidly progress over 1–2 days. Chest CT scan findings inCOVID-19 are more specific, including bilateral, multi-lobar, ground-glass opacification,which can become very extensive with disease progression, and multifocal consolidativeopacities with surrounding spared tissue.Although these typical chest CT scan findings are highly informative, they are of limitedvalue in resource-limited settings, where access to CT scanners is in general very limited.In addition, obtaining a chest CT scan is highly impractical once a patient is admitted tothe intensive care unit for invasive ventilation because this requires dangerous andlabor-intensive transportation to the CT scanner. Last but not least, there is a risk ofcontamination of the CT scanner and, thus, spread of the infection to other patients withinthe hospital.5 Lung ultrasound is easy to perform and hasalmost no costs after the initial purchase of the ultrasound machine . For poor patients in low- or middle-income countries, even achest X-ray can be a considerable out-of-pocket expenditure if these costs are not coveredby insurance or government funds. Also, chest X-rays in low-resource settings are often ofpoor quality, with a much lower sensitivity than LUS to detect pleural or parenchymalabnormalities.6The potential benefit of point-of-care LUS as a diagnostic tool in COVID-19 should behighlighted. Lung ultrasound is a well-established, noninvasive, rapid, repeatable,sensitive, bedside method to detect pulmonary pathology, including pneumothorax, pleuraleffusion, and pulmonary infiltrates or consolidations. Lung ultrasound has even beenadvocated as an alternative for chest X-ray and chest CT scan for diagnosing acuterespiratory distress syndrome.This information supports more extensive deployment of point-of-care LUS in COVID-19patients, in particular in settings where resources are limited. The COVID-19 casepresented by Chaisith describes LUS abnormalities observed at the 12th day of hospitaladmission. They did not show whether earlier COVID-19–related lung pathology isdetectable by LUS, but this is probably the case. Whether LUS findings showCOVID-19–specific features will need further exploration because this could providea valuable diagnostic tool to distinguish COVID-19 from other pulmonary infections, andsuggests the possibility of a severity score based on LUS findings. For example, the usualabsence of pleural fluid in COVID-19 could be of diagnostic value because pleural fluid canbe easily detected by LUS and is often present in patients with bacterial pneumonia andother conditions that result in respiratory distress, such as pulmonary congestion withheart failure.Lung ultrasound could confirm on a larger scale whether the abnormalities observed on chestCT scan of multifocal opacities alternating with normal aerated lung represent a commonlung pathology in COVID-19. This could have important practical consequences forventilation strategies in individual patients. Focal areas of dense atelectasis, which aredifficult or not to reopen, surrounded by remarkably compliant normal lung tissue, wouldimply that in patients needing invasive ventilation, high positive end-expiratory pressures(PEEP) may not be beneficial, and could even be harmful. Indeed, too high PEEP could causeoverdistension and damage of ventilated unaffected lung areas, whereas the infected areaswith atelectasis remain unventilated. This could lead to an increase in intrapulmonaryshunt, worsening the already grave hypoxemia in severe COVID-19 disease. To further provethis concept, LUS could be used as a real-time imaging tool to evaluate the success orfailure of attempts to reopen atelectatic lung tissue, for example, with high PEEP. Earlyexperience from Amsterdam, the Netherlands, suggests that an emphasis on prone positioningand use of much lower PEEP in COVID-19 patients than in others with respiratory failureresults in good patient outcomes .In summary, LUS is a promising additional imaging tool in patients with COVID-19, inparticular in resource-limited settings in low- and middle-income countries.


Older people living with HIV/AIDS (PLWHA) face different mental and neurocognitive challenges related to their health and well-being. Using data from a cross-sectional study (n=250) on older (age 50-69) gay men living with HIV/AIDS in NYC, this study examined the multi-level associations between self-reported neurocognitive functioning, mental health, and key sociodemographics . Findings suggest those who have higher self-reported neurocognitive functioning have higher levels of education, better self-rated health, and lower levels of PTSD and depression (p<0.01). Differences were not observed based on race/ethnicity, financial situation, and age. The overall findings demonstrate educational differences in self-reported cognitive functioning among older HIV+ gay men and highlight the importance of enhancing interventions and policies to promote better cognitive and mental health outcomes. More research is warranted to understand the intersection of education and cognitive performance among other sub-groups of PLWHA to understand whether these findings are consistent.


Since asymptomatic infections as “covert transmitter”, and some patients can progress rapidly in the short term, it is essential to pay attention to the diagnosis and surveillance of asymptomatic patients with SARS-COV2 infection. CT scan has great value in screening and detecting patients with COVID-19 pneumonia, especially in the highly suspected or probable asymptomatic cases with negative RT-PCR for SARS-COV2. This study aimed to detect incidentally COVID-19 pneumonia on medical imaging for patients consulting for other reasons. In the worldwide COVID-19 outbreak, asymptomatic infected individuals may become the contagious source of SARS-CoV-2; some of them progress rapidly to acute respiratory distress syndrome and systemic complications. Early detection has become crucial to ensure rapid prevention and timely treatment. So numerous healthcare professionals are involved in responding to the health crisis mostly with unknown infected patients. Chest CT imaging of asymptomatic cases with COVID-19 pneumonia has definite characteristics and the role of radiologists has been emphasized . In the From March 15 to May 10, 2020, 542 patients in Monastir, Tunisia who had a CT scan for different indications and who had a screening chest CT scan at the same time of the requested examination even for acute abdominal pain as well as patients who did requested chest CT scan were included. Three radiologists , reviewed all chest CT images and decided on positive or negative CT findings by consensus. The epidemiological history and clinical presentation were available for all readers. The radiologists classified the chest CT as positive or negative for COVID-19. For each patient, the chest CT scan was evaluated by these following characteristics: (1) ground-glass opacities, (2) parenchymal consolidation, (3) peripheral position of ground-glass opacities and consolidation, (4) number of lobes affected, (5) degree of involvement of each lung lobe in addition to overall extent of lung involvement measured by means of a “total severity score” as detailed below, (6) presence of nodules , (7) pleural effusion, (8) thoracic lymphadenopathy (defined as lymph node size of ≥10 mm in short-axis dimension), (9) small airways abnormalities , (10) central distribution of disease (“peribronchovascular” predominant disease) and (11) presence of underlying lung disease such as emphysema or fibrosis. Other abnormalities, including linear opacities, opacities with a rounded morphology, opacities with a “reverse halo” sign, opacities with a “crazy-paving” pattern, and opacities with intralesional cavitation, were noted. Ground-glass opacification was defined as hazy increased lung attenuation with preservation of bronchial and vascular margins, whereas consolidation was defined as opacification with obscuration of margins of vessels and airway walls. Each of the five lung lobes was assessed for degree of involvement and classified as none (0%), minimal (1-25%), mild (26-50%), moderate (51-75%), or severe (76-100%). Patients with chest CTs classified as a COVID-19 suspect had RT-PCR tests and were isolated. For patients with negative RT-PCR tests but positive CT results, clinical follow-up compared with serial chest CT scans and a second RT-PCR were carried out to further confirm the imaging diagnosis.Case 1 and 2 show an example of COVID-19 pneumonia incidentally discovered on chest CT. Case 3 shows an example of suspected coronavirus pneumonia but RT-PCR of SARS-CoV-2 result and other medical investigation redress the diagnosis.542 patients  were available for CT chest screening. Only nine patients (1.6 %) had positive CT scans and in which RT-PCR was made. Of 9 patients with positive CT scans results, only 22 % (2/9) had positive RT-PCR and 77% had negative test even for second RT-PCR. Of the 9 patients, five patients (55%) had ground-glass opacities and consolidation, four patients (45%) had only ground-glass opacities (with no consolidation). Two patients (22%) had opacities in one lobe, 6 patients (66%) had four affected lobes, and 1 patient (12%) had disease affecting all five lobes . Case 1 Case 1: CT images without intravenous contrast performed in a 62-year-old Woman consulting in the emergency room for abdominal pain and vomiting. The abdominal scanner was without significant abnormalities. The CT scan showed bilateral and subpleural pulmonary ground-glass predominant. It is associated with linear and sub segmental condensation (ensation .A RT-PCRCase 2: CT images without intravenous contrast performed in a 57-year-old men consulting in the emergency room for brain trauma following a loss of consciousness. The brain scanner was without abnormalities. The findings included bilateral subpleural and peripheral ground-glass opacities with pulmonary condensation predominant in the lower lobes (er lobes . Two dayCase 3: CT images obtained without intravenous contrast in a 52-year-old male following a chest CT scan as part of exploration of atypical chest pain without dyspnea and normal levels of cardiac enzymes. The first ECG showed no repolarization abnormalities. The CT scan demonstrated bilateral and central ground-glass with Broncho vascular bundle and interlobular septal thickening (ickening . InterstFor the nine patients with chest CTs classified as a COVID-19 suspect, specific management was pursued, including the requirement to wear a mask, immediate information of the suspicious imaging findings to the patient and the referring physician, and activation of the RT-PCR test procedure, as well as careful disinfection of the CT suite. All these infection control measures aimed to prevent potential transmission to other individuals, including other patients who are potentially vulnerable, radiology staff, relatives, and any other personal contacts. During the COVID-19 outbreak, the radiology staff, especially radiology technicians, must be aware and trained to any incidental detection of appearances suggestive of SARSCoV-2 infection. Such findings may be discovered not only on chest CT but, during any imaging performed for other clinical situations, also when the lungs are partially visible in non-pneumological studies. Therefore, while specific tracks for suspected or known COVID-19 patients have been established, the healthcare team should keep in mind that asymptomatic or paucisymptomatic carriers are potentially present in the non-COVID-19 pathway. Several consequences flow from this. First, radiology technicians might be unexpectedly exposed and should be provided with adequate protective equipment. Second, we recommend reviewing all available chest images within any imaging examination as soon as possible before the patient leaves the radiology facility to identify suggestive abnormalities. Third, in case of suggestive findings, the CT suite needs to be appropriately cleaned before the next examination, while patients should be quickly directed to the COVID-19 pathway. Taken together, these actions are likely to slow down the clinical workflow, and prolonged waiting times for outpatients should be avoided . MaintaiRT-PCR is currently considered as the gold standard diagnostic method for COVID-19. However, the sensitivity of this method in throat swabs in COVID-19 is around 59% . To dateThis study showed a low incidence of patients with COVID-19 pattern pneumonia on daily CT scan activity outside the hospital specific pathway. However, this situation is of critical consequences since radiologically visible COVID-19 pneumonia is associated with potential severe complication for patients and potential virus transmission within the health staff. Of note, once the outbreak will be under control and the number of cases declines, these emergency measures will be progressively discontinued. At the same time, the spread of SARS-CoV-2 will probably not end overnight, and some cases will still be diagnosed in the following months.The typical hallmarks of COVID-19 pneumonia reported on CT scans are characterized by bilateral lung involvement, multifocal ground-glass opacities, and consolidation in a typical peripheral with a posterior-dependent gradient and more consolidation in the postero-basal regions;Patients may have negative RT-PCR for COVID-19 at initial presentation despite chest CT findings typical of viral pneumonia.Ground glass opacities, consolidation, reticular pattern, and crazy paving pattern are typical CT manifestations of COVID-19;CT manifestations may associate with the progression and prognosis of COVID-19;Chest CT is recommanded for screening for COVD-19 for patients with clinical and epidemiologic features compatible with COVID-19 infection particularly when RT-PCR testing is negative.


We read with great interest the recent article by Chlebowski et al., who recommend the use of multiple laboratory tests including anti-factor Xa (anti-Xa) to optimally manage anticoagulation during ECMO . Anti-XaChlebowski MM, Baltagi S, Carlson M, Levy JH, Spinella PCThe authors agree that COVID-19 patients have increased anticoagulation needs and, as a result, multifactorial analysis of hemostasis utilizing thromboelastography (TEG) in these patients may be even more important due to the multidimensional hemostatic abnormalities that occur with COVID-19 infection , 7. The


The AG included experts in design, establishment and performance of challenges. This report summarizes issues that render a COVID-19 model daunting to establish  and it proffers prudent strategies for stepwise model development, challenge virus selection, guidelines for manufacturing challenge doses, and ways to contain SARS-CoV-2 and prevent transmission to household/community contacts. A COVID-19 model could demonstrate protection against virus shedding and/or illness induced by prior SARS-CoV-2 challenge or vaccination. A limitation of the model is that vaccine efficacy in experimentally challenged healthy young adults cannot


Patients with rheumatic diseases and those receiving immunosuppressive treatment are felt to be at greater risk of complications from this illness, though registry and trial data should help refine our understanding of these risks. We hereby describe a case of COVID-19 complicating an unusual rheumatic illness, resulting in severe multi-system disease and premature death.COVID-19, the infectious disease caused by the novel coronavirus SARS-CoV-2, and first described in Wuhan, China in December 2019, has affected more than 19 million patients worldwide and resulted in more than 700,000 deaths at the time of writing9/L), eosinophilia (25.4 x 109/L), raised C-reactive protein , positive rheumatoid factor (>200), antinuclear antibody (ANA) and anti-Ro. Bone marrow biopsy did not demonstrate evidence of haematological malignancy. A 69 year-old male presented to rheumatology and haematology with symmetrical polyarthritis, thrombocytopenia  allowed gradual prednisolone tapering to 3mg daily. Hydroxychloroquine was briefly added but discontinued due to headaches. MMF was discontinued after he developed fungal pneumonia followed by jaundice. Liver biopsy was consistent with drug-induced cholestasis, attributed to co-amoxiclav, and his liver function tests (LFTs) improved on ursodeoxycholic acid. Following a further deterioration in thrombocytopenia, hyperferritinaemia and new onset erythema nodosum, he had a repeat bone marrow examination. This demonstrated large areas of fibrosis and granulomatous inflammation with a dense, pleomorphic T-cell infiltrate, but no haemophagocytosis. Haematologists felt this was reactive and prednisolone dose was increased to 10mg daily.Six months later he developed cholangitis. Magnetic resonance cholangiopancreatography (MRCP) demonstrated a tight 4cm stricture of the distal common bile duct (CBD) within the head of pancreas, which was diffusely swollen without any clear focal mass. Serum amylase was mildly elevated (316 units/L). Concurrent CT thorax, abdomen and pelvis demonstrated bilateral ground-glass changes within the lungs, and a SARS-CoV-2 nasopharyngeal PCR test was positive, though he had no respiratory symptoms or oxygen requirement at that stage.Sadly, four days after the CT scan and before a planned endoscopic retrograde cholangiopancreatography (ERCP) could be performed, he became markedly hypoxic with plain chest x-ray features suggestive of COVID-19 pneumonia. Despite medical management, including doubling of his prednisolone dose, he rapidly deteriorated and died.This case highlights an unusual presentation of COVID-19 in a patient with a complex background of inflammatory arthritis with immune-mediated thrombocytopenia. At the time of his final illness, these conditions were managed with steroid monotherapy. Based on the COVID-19 risk matrix recommended by the British Society for Rheumatology, he was not identified as a patient requiring shielding.Cholangitis was the major problem precipitating his final admission to hospital, and at the time of admission he had no respiratory symptoms. One week prior to this admission, his father-in-law had died of COVID-19 pneumonia, though they had not been in recent direct contact. Interstitial lung changes were incidentally noted on a CT performed to identify the cause of cholangitis, which prompted the nasopharyngeal PCR that detected SARS-CoV-2. This occurred prior to widespread routine testing of hospital inpatients for SARS-CoV-2 by PCR. Unfortunately he then rapidly developed COVID-19 pneumonia and died before the underlying cause of cholangitis could be definitively identified, though an MRCP demonstrated an obstructed CBD within a diffusely swollen pancreas, where a differential diagnosis of pancreatic malignancy or autoimmune pancreatitis was suggested by the reporting radiologist. There are emerging case reports of COVID-19 resulting in significant pancreatic injuryand a further recent laboratory analysis has suggested that ACE2 receptors, which are utilised by SARS-CoV-2 to gain entry to host cells, are highly expressed on cholangiocytes at a comparable level to type II alveolar cells. Whilst the ultimate cause of cholangitis will remain unknown in this patient, this case highlights the potential for atypical presentations and extra-pulmonary manifestations of COVID-19.Case report - Key learning points COVID-19 is a multi-system illness which can cause significant extra-pulmonary as well as pulmonary pathology, with emerging reports that the biliary tract and pancreas are frequently affected.Evidence to inform accurate prediction of which patients with rheumatic diseases are at highest risk of acquiring severe COVID-19 disease remains insufficient, with current shielding guidelines based on expert consensus.This case highlights the importance of widespread testing for COVID-19 in hospital patients, as not all patients carrying the SARS-CoV-2 virus will demonstrate classical respiratory features of the disease at the point of admission.


During malignant transformation, accumulated somatic mutations endow cancer cells with increased invasiveness and immunogenicity. Under selective pressure, these highly immunogenic cancer cells develop multiple strategies to evade immune attack. It has been well established that cancer cells could downregulate the expression of major histocompatibility complex, acquire alterations in interferon pathway, and upregulate the activities of immune checkpoint pathways. Besides, cancer cells secret numerous cytokines, exosomes, and microvesicles to regulate the functions and abundances of components in the tumor microenvironment including immune effector cells and professional antigen presentation cells. As the vital determinant of post-transcriptional regulation, microRNAs (miRNAs) not only participate in cancer initiation and progression but also regulate anti-cancer immune response. For instance, some miRNAs affect cancer immune surveillance and immune escape by interfering the expression of immune attack-associated molecules. A growing body of evidence indicated that cancer-derived immune modulatory miRNAs might be promising targets to counteract cancer immune escape. In this review, we summarized the role of some miRNAs in cancer immune escape and discussed their potential clinical application as treatment targets. Robust anti-cancer immune response consists of a series of stepwise immune events including the release of cancer-associated antigens, the processing and presentation of antigen presentation cells (APCs), the priming and activation of naïve T cells, the trafficking and migration of activated T cells, and the tumor-killing activity of effector cells , 2. ActuFor some patients, the undermined cytotoxicity of effector cells is not the only rate-limiting step of eliminating cancer cells. In these patients, alterations in some upstream events in cancer-immunity cycle such as the recognition of cancer antigens, the functions of APCs, and the infiltration of T cells hamper cancer immune clearance as well , 12. AddmiRNAs are a class of small, non-coding, single-strand RNAs which could silence target mRNAs by binding to corresponding 3′-untranslated region (3′-UTR) or open reading frame . It is wAlthough most patients have an intact immune system, some malignant cells could survive from immune attack and develop into clinically overt cancers . Under t+ T cells . Ca. Ca24]. + T cells [Zhou et al. reported that the apoptosis ratio of T cells increased after treated with B16 cell-derived exosomes . When th T cells . In sili T cells . Besides T cells . Meanwhi T cells . It was  T cells .+ monocytes, inducing the polarization toward M2-like phenotype and suppressing the expression of M1 phenotype-associated markers [Macrophages are usually categorized into pro-inflammatory (M1) populations and anti-inflammatory (M2) populations . Abundan markers . Similar markers . After u markers . Notably markers .Accumulating evidence has indicated that cancer-derived exosomal miRNAs are capable of regulating the abundance and function of MDSCs . Ren et As the most abundant cells of cancer stroma, cancer-associated fibroblasts (CAFs) secret multiple cytokines and extracellular matrix components such as collagens and fibronectins, which generate a physical barrier separating lymphocytes from tumor and inhibiting the infiltration of effector cells . Hyperac+CD8+ T cells [Due to the substantial influence of some cancer cell-derived miRNAs on anti-cancer immune response, it is promising to develop miRNA-based diagnostic tools and therapeutic applications. In NSCLC mouse models, it was found that miR-34a suppressed PD-L1 expression by binding to its 3′UTR region. Therapeutic injection of liposomal nanoparticles containing miR-34a mimics increased the abundance of TILs and decreased the ratio of PD-1 T cells . TheoretIn addition, some miRNAs are determinates of efficacy of immune checkpoint inhibitors. Zhang et al. found that circFGFR1 acted as the miRNA sponge of miR-381-3p and induced the therapeutic resistance to PD-1 blockade . BesidesApart from immune checkpoint inhibitors, it has been verified that some miRNAs affect the efficacy of other immunotherapies such as CAR T cells. In xenograft tumor of human colon cancer, miR-153 inhibited the expression of IDO and enhanced the effect of CAR T cells targeting epidermal growth factor receptor . In addi+ colon cancer cells. This co-delivering by exosomes showed potent anti-cancer effect in mouse models and reversed the chemotherapy resistance to 5-Fluorouracil [Alteration in miRNA expression profile plays an indispensable role in carcinogenesis. Upregulated onco-miRNAs and downregulated tumor-suppressed miRNAs render cancer cells with enhanced viability and invasiveness. We noticed that more and more clinical studies try to predict the patients’ prognosis or treatment efficiency by analyzing miRNA expression profile. It was more refreshing that multiple onco-miRNA-targeted agents had been designed such as miR-RX34 liposomal. Besides, Liang et al. designed an engineered exosome which could deliver chemotherapeutic drugs 5-Fluorouracil and miR-21 inhibitor oligonucleotide to Her2rouracil . The effApart from participating carcinogenesis, some specific miRNA expression pattern could predict cancer immune evasion. We proposed that it would be feasible to utilize miRNA expression profiles and other parameters to construct a comprehensive framework for evaluating patients’ immune state. This evaluation is meaningful to determine further treatment options. Besides, normalizing these immunosuppressive miRNA expression patterns might have a synergistic effect with simultaneous immunotherapy.


The mTOR inhibitor Rapamycin has tumor inhibitory properties; and it is also used as an immunosuppressive agent after organ transplantation. However, prolonged Rapamycin treatment re-activates Akt and can promote cancer growth. Honokiol is a natural compound with both anti-tumorigenic and anti-inflammatory properties. Here, we assessed the anti-tumor effects of Rapamycin and Honokiol combination in renal cell carcinoma (RCC). Receptor tyrosine kinase c-Met-mediated signaling plays a major role in RCC growth. We observed that compared with Rapamycin alone, Rapamycin + Honokiol combination can effectively down-regulate c-Met-induced Akt phosphorylation in renal cancer cells; and it markedly inhibited Ras activation and cell proliferation and promoted G1 phase cell cycle arrest. The combination treatment significantly induced ROS generation and cancer cell apoptosis even when c-Met is activated. Importantly, Honokiol, but not Rapamycin, decreased c-Met-induced expression of the co-inhibitory molecule PD-L1, implied in the immune escape of renal cancer cells. In mouse renal cancer cells and Balb/c splenocytes co-culture assay, Rapamycin + Honokiol markedly potentiated immune-cell-mediated killing of cancer cells, possibly through the down-regulation of PD-L1. Together, Honokiol can effectively overcome the limitation of Rapamycin treatment alone; and the combination treatment can markedly restrict the growth of RCC, with particular importance to post-transplantation renal cancer. There are very limited treatment options for advanced renal cell carcinoma (RCC). The five-year survival rate for patients with metastatic RCC is less than 10% as the tumors get highly resistant to standard chemo- and radiotherapy ,3,4. ThuThe development and rapid progression of cancer is a major problem in immunosuppressed patients, like patients receiving an organ transplant ,6. InterThe mTOR inhibitor rapamycin (RAPA) is often used in transplant patients to prevent organ rejection through the down-regulation of T cell proliferation . Interes18H18O2), a biphenolic natural product originally isolated from Magnolia obovate, is a promising agent for mediating anti-inflammatory, pro-apoptotic and chemopreventive functions [Honokiol  to prevent post-transplantation renal cancer. In the present study, we show that that the combination treatment with RAPA and Honokiol effectively restricts the growth and cell cycle progression of renal cancer cells by inhibiting the c-Met-HO-1 axis; it also down-regulates the expression of PD-L1, which plays a major role in the immune escape of renal cancer cells. Thus, this combination therapy can have a great potential to prevent/restrict renal cancer in both immunosuppressed as well as other RCC patients.The mTOR inhibitor RAPA is used in transplant patients to prevent allograft rejection; however, as discussed earlier, prolonged RAPA treatment can promote Akt activation through the withdrawal of negative feedback loop, and thus can facilitate tumor growth . Here, wHere, we first checked how the RAPA + Honokiol combination treatment can regulate renal cancer cell proliferation. As shown in As abrupt cell cycle regulation is important for cancer progression, we next checked the effect of RAPA and Honokiol on cell cycle distribution of renal cancer cells. We found that Honokiol caused G1 phase arrest of renal cancer cells compared with controls; and in combination with RAPA, it further increased the G1 phase cell cycle population D. Next, Many chemotherapeutic agents induce high levels of cellular reactive oxygen species (ROS), which can cause oxidative damage to macromolecules leading to the induction of apoptosis . Thus, wAs mentioned before, the c-Met-induced pathway promotes the growth and survival of renal cancer cells and mediates chemoresistance . We wantHere, we wanted to study if the RAPA + Honokiol combination is more effective to induce apoptosis in c-Met knockout renal cancer cells. We have generated stable c-Met knockout renal cancer cells using CRISPR/Cas9 /(CRISPR associated protein 9) gene editing technique A. We conPD-1 and its ligand PD-L1 are key immune checkpoint regulatory molecules that act as co-inhibitory factors to limit the T cell responses . We haveAs mentioned before, c-Met is either highly over-expressed or mutated in renal cancer cells compared with normal renal epithelial cells . Thus, wOur previous experiments clearly showed that the combination treatment with RAPA + Honokiol inhibits the expression of the negative co-stimulatory molecule PD-L1 on renal cancer cells. Here, we wanted to evaluate the functional significance to know if this combination treatment can facilitate the immune-mediated killing of cancer cells. To this end, we performed a co-culture experiment utilizing the splenocytes from Balb/c mice and syngeneic renal cancer cells (RENCA) that were pre-treated with combinations of RAPA and Honokiol or the vehicle alone (control). As expected (data not shown), there was increased basal apoptosis of cancer cells when they were co-cultured with splenocytes. As shown in New therapeutic combinations are needed for the treatment of advanced renal cancer, which is also a major problem in transplant patients . HonokioRAPA, the mTOR inhibitor, is used for the treatment of renal cancer patients; it is also being used for transplant patients to prevent allograft rejection . HoweverCell cycle dysregulation is one of the important hallmarks of cancer cells. Many chemotherapeutic agents induce cell cycle arrest to inhibit cancer cell proliferation; and they promote apoptosis . PreviouPD-L1 is one of the key immune-checkpoints that can play an important role in immune escape of cancer cells; and it has been reported that PD1 expressed by tumor-infiltrating immune cells is associated with poor outcome of renal cancer patients . We haveAs mentioned above, RAPA is used for the treatment of renal cancer, and it is also a good treatment option for the transplant patients to prolong their allograft survival; however, it has many limitations. Our results suggest that the combination therapy can have great potential to overcome the limitation of RAPA treatment, and also to maintain the immune suppression. The detailed mechanism of action for RAPA + Honokiol combination therapy still needs to be explored. PI-3K-Akt-mTOR pathway has significant cross-talk with other signaling molecules . The oncIn our previous studies, we have checked the individual effect of either Honokiol  or RAPA Together, our observations suggest a novel combination therapy using RAPA + Honokiol that can effectively inhibit c-Met-induced and Ras-mTOR-mediated pathway(s) to restrict renal cancer growth as well as the immune escape of tumor cells. It can overcome the limitation of RAPA treatment and utilize its beneficial effects. Also, this combination treatment has significant therapeutic importance for the prevention of post-transplantation renal cancer. Due to the anti-inflammatory properties of Honokiol (in addition to its anti-tumorigenic function), it can be utilized for the treatment of transplant patients to prevent allograft rejection.Honokiol (HNK) and Rapamycin (RAPA) were purchased from Selleckchem. For Western blot analysis, primary antibodies against CDK2, CDK4, CDK6, Cyclin D1, p21, Bcl-2, Bcl-xL, c-Met, phospho-c-Met, HO-1, Akt, mTOR and S6 and species-specific secondary antibodies were obtained from Cell Signaling. Antibody against β-actin was purchased from Sigma Aldrich. Anti-PD-L1, phospho-Akt, phospho-S6 and phospho-mTOR antibodies were purchased from Thermo Fisher Scientific. Recombinant human hepatocyte growth factor (HGF) was purchased from Peprotech. Human renal cancer cell lines (786-0 and ACHN) and mouse renal cancer cell line RENCA were obtained from American Type Culture Collection (ATCC). 786-0 and RENCA cell lines were maintained in RPMI 1640 medium. ACHN cells were maintained in EMEM medium. All medium were supplemented with 10% fetal bovine serum (FBS) and 1% penicillin-streptomycin antibiotics . Normal renal proximal tubular epithelial cell (RPTEC) was obtained from Lonza, and was grown in renal epithelial cell basal medium with SingleQuots growth supplements .Renal cancer cells (786-0) were co-transduced with lentiviral particles encoding Cas9 and gRNA targeting either c-Met or control . Following antibiotic selection, stable clones were screened through Western blot to check the expression levels of total Met and HGF-induced phospho-Met. Clones with confirmed c-Met knock-out were selected and utilized.Briefly, 10,000 cells/well were seeded in 96 well plate. Following treatments (as described), media was removed, and 10 μL of 5 mg/mL MTT -2,5-Diphenyltetrazolium Bromide) dye  was added to each well. Cell proliferation assay was performed using the MTT kit according to manufacturer’s protocol (Thermo Fisher Scientific). Briefly, plates were incubated in dark for 4 h; and after incubation formazon crystals were dissolved in DMSO (Dimethyl Sulfoxide) and absorbance was measured at 570 nm in a plate reader, and corrected against blanks, which consisted of culture medium processed in the same way as above in the absence of cells.5 cells were seeded in each well of 6 well tissue culture plates; and cells were allowed to attach and grow overnight. Cells were then serum starved for 24 h to synchronize them in Gap-1 phase. Following treatments, cells were collected through trypsinization, and stained with Propidium Iodide, and flow cytometry was performed on a FACSCalibur to assess the percent of cells in different phases of cell cycle.In total, 1 × 105 cells were seeded in each well of 6 well tissue culture plates and allowed to attach and grow overnight. Following treatments, the cells were collected through trypsinization; and they were stained using an allophycocyanin (APC)/FITC (Fluorescein isothiocyanate)-conjugated apoptosis detection kit (Thermo Fisher Scientific) according to manufacturer’s protocol. Cells were then analyzed by flow cytometry on a FACSCalibur. Briefly, 1 × 106 cells) were added to the culture of RENCA cells grown in 6-well tissue culture plates. Following 72 h of incubation, supernatant containing splenocytes and unattached dead RENCA cells was removed. The adherent RENCA were collected by trypsinization and subjected to apoptosis assay as described earlier.Splenocytes were isolated from the spleens of BALB/c mice following standard protocol. Briefly, extracted spleen was minced under aseptic condition in RPMI 1640 medium containing 10% FBS. Large tissues in the suspension were removed using 40 μm nylon mesh cell strainer and splenocytes were collected by centrifugation. Pellets were resuspended in fresh RPMI 1640 medium and then utilized in co-culture experiments. For co-culture experiment, isolated splenocytes (1 × 10The Active Ras Pull-Down and Detection Kit (Thermo Fisher Scientific) was used to measure the active-GTP-bound form of Ras in the cell lysate. This kit utilizes specific Ras-binding domain (RBD) of Raf-1 that can bind active GTP-bound form of Ras. The cells were lysed and incubated with GST-Raf-1-RBD and glutathione resin. The eluted samples were subjected to SDS (Sodium dodecyl sulfate)-polyacrylamide gel electrophoresis, transferred to a polyvinylidene difluoride (PVDF) membrane, and probed with anti-Ras antibody.5 cells were seeded in each well of 6 well tissue culture plates; and allowed to attach and grow overnight. Following treatments (as described), the cells were collected through trypsinization. Cellular ROS was detected utilizing a kit obtained from Enzo Life Sciences, New York, USA, and following manufacturer’s protocol.Briefly, 1 × 105 cells were seeded in each well of 6 well tissue culture plates; and allowed to attach and grow overnight. Following treatments (as described), the cells were trypsinized, washed, and resuspended in phosphate-buffered saline containing 2% FBS. Cells (either permeabilized or non-permeabilized) were stained with respective FACS antibodies. Following incubation and washing, stained cells were analyzed by flow cytometry.In total, 1 × 10Following treatments (as described), the cells were lysed and protein samples were resolved on SDS-polyacrylamide gels and transferred to a polyvinylidene difluoride membrane . The membranes were incubated with primary antibodies and subsequently incubated with peroxidase-linked secondary antibodies. Reactive bands were detected using chemiluminescent substrate (ThermoFisher) on X-ray films.t test. Differences with p < 0.05 were considered statistically significant. For combinatorial index (CI) compusyn software was utilized [Statistical significance was determined by Student’s utilized . CI valuAlthough the mTOR inhibitor Rapamycin (RAPA) has anti-tumorigenic properties, it has many limitations. On the other hand, the natural product Honokiol (HNK) has both anti-tumorigenic and anti-inflammatory properties. This study suggests the importance of a novel combination therapy using HNK and RAPA to restrict c-Met-induced growth and immune escape of renal cancer cells, and overcome the limitation of RAPA treatment. In addition, this therapeutic combination has great potential to prevent the development of renal cancer in transplant patients. Together, RAPA + HNK combination can act as novel therapeutics for the treatment of renal cancer, with importance to post-transplantation cancer.


Mutations in the gene coding for tau, MAPT, can cause FTLD-tau, directly linking tau dysfunction with disease . Another protein, TDP-43, comprises aggregates which are the primary hallmark of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD-TDP), and mutations in the gene coding for TDP-43, TARDBP, can cause disease . To model tau or TDP-43 proteinopathies, transgenic C. elegans have been generated that express the full-length human protein pan-neuronally. These worms exhibit significant uncoordinated movement on plates and impaired thrashing in liquid . However, tau- and TDP-43- expressing worms are not paralyzed; they still move their heads and have some motility on the plate  which are not captured in standard crawling or thrashing assays. To assay differences in total activity, we used a WMicroTracker ARENA System . The ARENA captures population level activity data by relying on optical interferometry, which uses a large array of infrared LED microbeams to detect both the movement and position of worms on a culture plate. Disruption of an LED microbeam by worm movement is recorded by repeat scans of the 6-well culture plate, and allows for real-time processing. The software identifies changes in the location of disrupted beams between scans and assigns an activity score based on differences identified between each consecutive scan (Simonetta SH). Both tau- and TDP-43- expressing worms had significantly less activity per minute than N2 . Further, we found the ARENA- assessed activity data recapitulated the relative severity of phenotypes among the strains as measured by motility assays. For example, both CK10 (tau V337M) and CK144 (tau WT) have significantly uncoordinated movement when crawling or thrashing in liquid, with CK144 having worse motility than CK10, due to its much higher burden of total tau protein expressed . Likewise, CK410 (TDP-43 WT) worms have slightly impaired motility compared with N2 when crawling on a plate, CK423 (TDP-43 M337V) are severely uncoordinated, and CK426 (TDP-43 A315T) have the most severe uncoordinated phenotype. The relative toxicities of these strains stem from the effects of the mutations, as TDP-43 protein expression is relatively even among these transgenic strains . Interestingly, the ARENA captures activity of these severely uncoordinated worms that move poorly in motility assays such as crawling on an NGM plate or thrashing in liquid . Therefore, ARENA assessment of aggregate activity may be a more accurate metric for capturing non-locomotor movement of C. elegans that are severely uncoordinated.Aggregates of the protein tau are the hallmark of several neurodegenerative diseases including Alzheimer’s disease, frontotemporal lobar degeneration (FTLD-tau), progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), Pick’s disease, and chronic traumatic encephalopathy (CTE) . The plate was placed in the ARENA 15 minutes before starting the run to allow worms to acclimate. 14 activity scores were collected per strain over 60 minutes. Statistical analysis was performed with GraphPad Prism 8.All worms used were staged by way of timed egglay, and grown at 16Strains UsedN2 BristolbkIs10  IIICK10 bkIs144  IVCK144 bkIs410  IICK410 bkIs423  IVCK423 bkIs426  IICK426


Stem cells work with their niches harmoniously during development. This concept has been extended to cancer pathology for cancer stem cells (CSCs) or cancer reprogramming. IGF-1R, a classical survival signaling, has been shown to regulate stem cell pluripotency, CSCs, or cancer reprogramming. The mechanism underlying such cell fate determination is unclear. We propose the determination is due to different niches in embryo development and tumor malignancy which modulate the consequences of IGF-1R signaling. Here we highlight the modulations of these niche parameters , and the targeted stem cells  and CSCs, with relevance to cancer reprogramming. We organize known interaction between IGF-1R signaling and distinct niches in the double-sided cell fate with emerging trends highlighted. Based on these new insights, we propose that, through targeting IGF-1R signaling modulation, stem cell therapy and cancer stemness treatment can be further explored. The development of an embryo requires delicate and precise control over cellular mechanisms to establish a structural and functional organism from the stem cells. Recent advances in stem cell research have revealed the detailed processes of embryogenesis, stem cell differentiation, and cell reprogramming. In contrast to embryogenesis, cancer is considered a dysregulated cellular process. Notably, cancer growth use many of the machinery originally used in the development processes, but they are deregulated for cancer growth and metastasis  signaling was recently shown to regulate stem cell characteristics during embryogenesis and tumorigenesis  are proteins secreted by cells to modulate the bioavailability of IGFs [reviewed in Baxter ]. They cCells receive diverse signals from extracellular microenvironment and respond accordingly. Among different microenvironment factors, niche hypoxia is one of the most common conditions. Physiologically, hypoxia in the early embryonic stage is crucial in stem cell functions, pluripotency, and organ development  and the IGF-1R expression in pancreatic cancer cells, and such IGF-1R signaling promotes cell mobility -derived condition medium . We found that IGF-1R signaling supported the pluripotency gene expression of OCT4, SOX2, and NANOG in AP+ GSCs. Moreover, IGF-1 was secreted by AP+ GSCs as well as testicular stromal Leydig cells to form an autocrine and paracrine signaling loop. Notably, laminin enhanced the colony-forming ability of AP+ GSCs, indicating the role of the ECM in assisting IGF-1R-mediated stemness.Mouse germline stem cells are responsible for gamete formation during embryogenesis. Our previous study established a serum-free culture system to investigate the defined component of the pluripotency regulation of pluripotent germline stem cells   and BM-MSC-derived adipocytes revealed that IGF-1R signaling was highly involved during the adipogenic differentiation of BM-MSCs  through the JNK/p38 MAPK pathway in dental pulp–derived MSCs  and is associated with tumorigenesis -infected HCC patients. Histological staining of IGF-1R in patients with HBV+ HCC is positively correlated with pluripotency gene expression and worse clinical outcomes. Furthermore, expression of OCT4/NANOG in tumor cells is positively correlated with the amount of infiltrated immune cells within the tumor region. Inflammation-condition medium derived from lipopolysaccharide-stimulated HBV+ HCC induces the expression of stemness gene OCT4 and NANOG through an IGF-1R-dependent mechanism, suggesting the possible role of active inflammation in controlling IGF-1R-mediated cancer stemness  infection was reported to increase the expression of IGF-2 through IGF-1R/MEK/ERK signaling . Notably, re-coculturing these differentiated cancer cells with CAFs reversed this pattern, suggesting that the microenvironment may be involved in the reprogramming of cancer cells to their CSC state . Fibulin-3 is an extracellular glycoprotein expressed in various tissues and involved in embryonic development  through lentiviral transduction. This IGF-1/IGF-1R signaling in cardiac stem cells promotes stem cell survival and protects surrounding cardiomyocytes from apoptosis after infarction. Intramyocardial transplantation of these IGF-1-overexpressing cardiac stem cells in the infarcted area also preserves stem cells in the damaged region and increases myocardial regeneration without affecting its differentiation into cardiomyocytes, smooth muscle, or endothelial cells  but not the non-side-population cells, indicating the role of IGF-1R in CSC features. Targeting IGF-1R with figitumumab reduces side population cells and ALDHIn this review, we highlight the modulation interplay between IGF-1R signaling and microenvironments as well as how this interaction modulates IGF-1R-mediated stemness in stem cells, CSCs, and cancer reprogramming. The implications are 2-folds. The first is about IGF-1R. Given the consequences of the interaction between IGF-1R signaling and niche microenvironments, we reviewed the importance of IGF-1R signaling in regenerative medicine and cancer treatment in terms of stem cell therapy and therapeutic targets toward the cancers with stemness-related properties. Future research will focus on unraveling how IGF-1R signaling regulates stem cell features and to explore the underlying factors that control the dual consequences of IGF1R-mediated stemness. The second is about niche modulation perspective. We contemplate that niche properties can be modulated by adjusting parameters such as extracellular matrix, oxygen tension, cytokines, in different physiological and pathological conditions. The outcome is mediated through selective hub pathways such as IGF-1R signaling in this case, but can be Wnt/beta-catenin in other cases. It is speculative, but we hope more discussions and future investigations along this line can enrich our understanding of stem cell – niche interactions in the future.P-CC, Y-CK, C-MC, and Y-HH: conception and design, writing, review, and/or revision of the manuscript. Y-HH and C-MC: study supervision. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.