Platelets have received increasing attention for their role in the pathophysiology of infectious disease, inflammation, and immunity. In sepsis, a low platelet count is a well-known biomarker for disease severity and more recently authors have focused their attention on the active role of platelets in the pathogenesis of multi-organ failure. Septic shock is characterised by a dysregulated inflammatory response, which can impair the microcirculation and lead to organ injury. Being at the crossroads between the immune system, clotting cascade, and endothelial cells, platelets seem to be an appealing central mediator and possible therapeutic target in sepsis. This review focuses on the pathogenic role of platelets in septic organ dysfunction in humans and animal models. Sepsis is a complex syndrome characterized by a disordered immune, endocrine, and metabolic response to infection. This exaggerated response can lead to multi-organ failure (MOF), shock, and death. According to the new definition of sepsis, organ dysfunction and a dysregulated immune host response are the key factors that differentiate infection from sepsis . The sevHematological failure is common in patients with septic shock; the correlation between thrombocytopenia and sepsis was first demonstrated over 40 years ago . ThromboPlatelets are anucleated cells that play an established role in hemostasis and coagulation. However, hemorrhagic complications during sepsis are rare and rarely lead to death. Attention has also been focused on their role in the immune system . PlateleIn this review the following questions will be considered: What are the possible mechanisms of platelet dysfunction leading to multi-organ failure during sepsis? What evidence do we have for these mechanisms? Is platelet function a potential therapeutic target in sepsis?Platelet interaction with immune and endothelial cells is a well-known and conserved response against infection. Activated platelets interact with other cells via two main mechanisms: (1) expression of receptors on cellular surface; and, (2) release of cytoplasmic granules that contain immunomodulatory proteins. CD40, CD154, Toll-like receptors, TREM-1 ligand, P, and E selectin are all expressed during platelet activation. α-granules containing chemokines, adhesive proteins, and clotting factors are usually stored at cytoplasmic level and on stimulation can be released to promote immunomodulation .Platelets play an important role in the guidance and activation of neutrophils, supporting leukocyte rolling, adhesion, and transmigration in peripheral vessels. Leukocytes that interact with platelets express a higher number of receptors related to infection and inflammation and have a stronger bactericidal capacity. Platelet-leukocyte complexes (PLCs) can be measured in vivo and increased numbers of PLCs have been shown both in animal models of sepsis and humans. Reduced numbers of PLCs are associated with progression of MOF ,19 and aFollowing is a brief description of the mechanisms involved in platelet cross-talk with other cell-types during sepsis.TREM-1 is a well described leukocyte receptor that is expressed in response to infection. Platelets express a ligand for TREM-1, levels of which correlate with the severity of sepsis and have been studied as a potential therapeutic target ,21.Platelets are also involved in the formation of Neutrophil extracellular traps (NETs), a complex web-like structure of DNA with proteolytic activity built by neutrophils, with the ability to trap microorganisms and facilitate their clearance . NETs maPlatelets show complex interactions with neutrophils and the endothelium. Vasodilation, increased permeability, adhesion of immune cells, alteration in the glycocalyx and cytokine release become dysregulated during sepsis. Ince et al. have widely reviewed the important role of endothelium in sepsis .P-selectin mediated adhesion is an important platelet-endothelial-leukocyte interaction in sepsis. P-selectin is contained in platelet α-granules and is expressed on membrane surface after activation ,26; inhiICAM-1 expression on endothelial cells is induced by activated platelets and promotes neutrophil adhesion. An animal model of acid-induced lung injury suggests that it may be a potential therapeutic target: inhibition of ICAM-1 mediated platelet-endothelial-neutrophil interaction resulted in increased animal survival time and less hypoxia .Another interesting immunomodulatory mechanism involves microparticles (MPs). MPs are small vesicles released from the cell surface of platelets, which function as storage for coagulation factors and cytokines . ElevateOur group has investigated the involvement of thrombopoietin (TPO) in platelet-leukocyte interaction and the development of organ damage in sepsis. TPO is the growth hormone involved in thrombopoiesis. In normal physiological states it promotes platelet production through megakaryocyte stimulation and is released by platelets themselves upon activation. TPO levels are also increased during inflammatory states , enhanciIn summary, there are several receptors involved in platelet cross-talk with immune and endothelial cells during sepsis with roles leading to organ damage. To date, none of these mediators have been successfully targeted in clinical practice. However, future benefits may result from further characterization of the molecular and cellular mechanisms involved in these processes and contribute to a theragnostic approach to treating sepsis and improving mortality.Platelet-endothelial adhesion, platelet-leukocyte aggregates, and NETs all contribute to the formation of microthrombi in small vessels. The cells involved release cytokines and chemokines resulting in further cellular recruitment, which can become a pathological self-sustaining dysregulated process resulting in septic shock. The formation of microthrombi in the vessels triggered by the inflammatory response and the subsequent recruitment of immune cells and platelets is known as immunothrombosis .Immunothrombosis contributes to microvascular dysfunction, which is a hallmark of organ damage in sepsis . CapillaThe final acceptor of oxygen at the subcellular level is the electron transport chain in mitochondria. Mitochondrial dysfunction has been widely investigated as a possible mechanism of organ damage during sepsis. This concept is supported by the absence of widespread cellular apoptosis and necrosis in patients with MOF , and by Acute respiratory distress syndrome (ARDS) is one the most severe complications of sepsis and is characterised by increased alveolar-capillary barrier permeability, pulmonary oedema, and severe hypoxemia. Patients with ARDS may require intubation and mechanical ventilation and current standard therapy includes lung protective ventilation to reduce lung trauma generated by high pressure in alveoli. Barotrauma is correlated with increased inflammation and worse prognosis .Leukocytes and platelet recruitment, intravascular coagulation, endothelial damage, loss of surfactant, oxidative stress are all mechanisms underlying severe lung damage in sepsis. Post mortem biopsies of patients who died with ARDS have shown excess numbers of platelets and neutrophil deposition in pulmonary vessels .The literature describes several roles for platelets in the pathogenesis of ARDS, in both animal and human studies; platelet depletion has been shown to correlate with reduced recruitment of neutrophils in lung interstitium  and incrEnhanced platelet activation has also been demonstrated in bronchoalveolar lavage of patients with ARDS .About 80% of all septic patients have some degree of coagulopathy. DIC (disseminated intravascular coagulation) is a condition involving uncontrolled systemic activation of the clotting cascade leading to clotting factor consumption and microvascular thrombosis. Complications include thrombotic and hemorrhagic events. No specific treatment has been identified so far and management of DIC complication can be very challenging in acute phases of sepsis. For all these reasons mortality is very high. Several anticoagulation treatments have been studied in clinical trials with no improvement in mortality .Platelets play a key role in normal hemostasis, stabilising the clot at endothelial level. During inflammatory states, platelets also act as amplifiers for clotting factor activation and cell recruitment. In particular, platelet-neutrophil aggregates are platforms for thrombi generation and that is the trigger for NET release ,68.A selective mechanism that is able to target infection-induced uncontrolled coagulation and preserve normal coagulation, needs to be identified. NET inhibition seems to be the most appealing approach, in particular inhibition of the NET associated protein histone H4, which has been shown to protect from DIC in an animal model of sepsis . Also, iAKI (acute kidney injury) is a frequent complication of sepsis, the pathophysiology and management of which are still controversial. Leukocyte infiltration in the septic kidney has been widely shown in animal models and septic patient; leukocyte depletion seems to reduce renal injury . P-selecA certain degree of cardiac impairment has been demonstrated in up to 80% of septic patients, although agreement on a definition of septic cardiomyopathy has still not been reached. Interestingly, sepsis induced cardiac impairment resolves within 7–10 days. Humoral factors are regarded as the most likely cause, although nitric oxide modulation and leukocyte recruitment have also been suggested in the pathogenesis .Incubation of platelet-derived MPs with isolated heart and papillary muscle preparations induces a decrease in myocardial contraction in vitro , howeverOur group has shown that pretreatment with TPO prevents septic serum-induced myocardial contractility depression .Acetylsalicylic acid (ASA) and P2Y12 inhibitors are prescribed worldwide in the secondary prevention of cardiovascular disease. ASA inhibits platelet function through the blocking of COX-1. Clopidogrel is a platelet membrane P2Y12 receptor inhibitor, thereby preventing ADP (adenosine diphosphate) activation. Antiplatelet drugs have an important anti-inflammatory effect, and can reduce C-reactive protein, P-selectin, and leukocyte-platelet aggregates ,77, and Animal studies, retrospective, and observational clinical studies have shown that antiplatelet drugs may reduce MOF, hospital stay, and mortality in critically ill patients, including those affected by sepsis ,81,82,83LIPS-A trial is a recently completed randomised controlled trial (RCT) that has included 195 patients per group at risk of developing ARDS. Treatment with aspirin was not correlated with improvement in terms of risk of developing lung injury .Other ongoing randomized controlled trials are expected to give a definitive answer. Details of ongoing RCTs are summarised in Emerging evidence highlights the role of platelets as immune mediators. Given their interaction with immune cells, endothelium, and clotting factors, and the widespread use of antiplatelet drugs in the general population, platelets seem an appealing therapeutic target in sepsis. Data from studies of both animal models and septic patients have shown the contribution of platelets to multi-organ dysfunction. The ongoing randomized controlled trials are expected to give more answers on the clinical effect of platelet inhibition in sepsis prevention and treatment.


Although the US Preventive Services Task Force recommends against routine prostate cancer screening with prostate-specific antigen (PSA) testing, specialty organizations support screening via shared decision making between providers and selected patients. While discussions about advantages and disadvantages of testing are a feature of patient-centered care, it is unclear how provider recommendations and the presence of a personal doctor influence testing in the presence of such discussions.We used the 2013 Behavioral Risk Factor Surveillance System to identify 1,737 male respondents surveyed about their PSA testing decisions. We describe the prevalence of provider recommendations and utilize weighted multivariable logistic regression models to examine the impact of provider recommendations and presence of a personal doctor on routine testing while accounting for patient-provider discussions about advantages and disadvantages.The majority (70.4%) of respondents reported some form of discussion with providers about testing and most underwent screening in accordance with provider recommendations. In multivariable analyses, men whose providers had never recommended PSA test were less likely to receive screening , and patients who did not identify a personal doctor in their care were less likely to undergo testing .Provider recommendations and having a personal doctor are associated with routine PSA testing. These findings suggest that providers and policymakers should be aware of how the content and context of communication with patients, beyond discussions of risks and benefits, can influence routine PSA testing behaviors. The role of routine prostate cancer screening with prostate-specific antigen (PSA) testing continues to be debated . AlthougDiscussions about risks and benefits are a feature of patient-centered care  and can In this analysis, we examine the association between these features of patient-provider discussions–provider recommendations about testing; continuity as defined by patients’ perception and ability to identify at least one “personal doctor” in their care–and the likelihood of routine PSA testing in men for whom shared decision making could be considered.We used the 2013 Behavioral Risk Factor Surveillance System, a national cross sectional tele- phone survey of non-institutionalized adults, to identify male respondents from the four states  that surveyed men about their testing decisions.4,5. This included male respondents aged 55 to 69 years who either reported receiving PSA screening as part of a routine exam or never receiving a PSA screening test. Respondents were excluded if they reported testing for any other reason, including personal or family history of prostate cancer, or if they were unsure why they underwent testing. Our analytic cohort included 1,737 men with complete data on PSA screening and covariates of interest.We restricted our sample to respondents eligible for age-based prostate cancer screening via shared decision making using conservative sub-specialty guidelines7, we defined risk/benefit discussions via four patterns: discussions of advantages and disadvantages, only advantages, only disadvantages, and no discussion.Descriptive statistics were calculated as weight-percentages. The odds of receiving routine PSA testing associated with provider recommendations and presence of a personal doctor were estimated with weighted logistic regression models adjusted for risk/benefit discussions and demographic, clinical, and access to care measures. Consistent with prior approachesStatistical significance was determined with two-tailed Wald-F tests at the 0.05 alpha level. Analyses were performed in SAS-callable SUDAAN (version 9.0.1) using sampling weights to account for the complex survey design.Overall, most of the men in our cohort were healthy, educated and able to adequately access health care . The majThe majority (70.4%) of respondents reported some form of discussion with providers about testing, and most (62.6%) reported that their providers recommended screening . PatientIn multivariable analyses, men whose providers had never recommended a PSA test were less likely to receive screening  than those whose providers had ever recommended it . SimilarCompared to men who had no discussions about advantages or disadvantages of PSA testing with providers, those who discussed only advantages , or dis- cussed both  were more likely to undergo testing. No significant differences were observed for men who only discussed disadvantages with providers  compared to those who had no discussions. Results were robust to adjustment for patient age, race/ethnicity, education, income, self-rated health, co-morbid conditions, insurance status, and delayed care due to cost.Our results underscore that routine PSA testing is not only associated with discussions of risks and benefits , but alsFirst, although shared decision making involves eliciting patient preferences and values, providers also impart their values through their recommendations, as well as their framing of risks and benefits. Our analysis builds on earlier work done before broad adoption of shared decision making  and is tThis reflects the fact that recommendations about PSA testing and discussions about PSA testing are related, but distinct, issues. Additional research should therefore seek to understand how provider motivations and values drive recommendations, as well as test the independent and combined effects of recommendations and discussions on PSA testing behavior. Ultimately, a combination of patient- and provider-focused policies that emphasize both appropriate recommendations as well as balanced discussions of risks and benefits are needed to improve the appropriateness of routine PSA testing.Second, the association between presence of a personal doctor and routine PSA testing also suggests that patients’ perceived continuity or familiarity with providers can influence testing independent of provider recommendations or discussions of risks and benefits. One implication of this result is that future work should evaluate how PSA testing behaviors are influenced by the context (where and with whom) as well as the content  of shared decision making.Our analysis is limited by an inability to determine causality, as well as potential underreporting and sampling, recall or non-response bias in a non-nationally representative sample. The sample also included small numbers of Hispanic or African American men (9.4% of the cohort), potentially high risk groups for whom alternative screening approaches may be indicated.Nonetheless, our findings suggest that providers and policymakers should be aware of how the content and context of communication with patients, beyond discussions of risks and benefits, can influence routine PSA testing behaviors.


Its high mortality rate has been attributed to therapeutic resistance and rapid, diffuse invasion – both of which are strongly influenced by the unique microenvironment. Thus, there is a need to develop new models that mimic individual microenvironmental features and are able to provide clinically relevant data. Current understanding of the effects of the microenvironment on GBM progression, established experimental models of GBM and recent developments using bioengineered microenvironments as  Glioblastoma (GBM), the most common form of brain cancer, is extremely lethal due to its rapid progression, resistance to treatment and high rates of recurrence. As reviewed here, the microenvironment that surrounds GBM tumors drives their progression. Development of effective treatments for GBM will require better experimental models that account for the tumor microenvironment and thus, can provide clinically translatable results. This review focuses on using biomaterials to create tumor-mimetic microenvironments as experimental platforms for cell culture. Glioblastoma (GBM), or grade IV glioma, is an extremely lethal cancer originating in the brain with a median survival time of only 12–15 months . AlthougExperimentally it has been challenging to isolate the influence of any individual feature of the complex GBM microenvironment on tumor physiology. Bioengineered platforms enabling modular control over these independent variables can potentially isolate these effects and identify new therapeutic targets. In the first part of this review, we discuss individual features of the microenvironment separately as independent variables affecting GBM physiology. In the second part, we discuss how biomaterials might be engineered to create complex models of this microenvironment in which both the integrated and decoupled effects of each feature can be robustly characterized. While researchers have made some progress controlling multiple aspects of the tumor microenvironment – for example, extracellular matrix (ECM), soluble biomolecule signals, physical properties and cell–cell interactions – within bioengineered microenvironments, major advancements to date have centered around methods to orthogonally control individual biochemical and biophysical features of the ECM. Thus, while other aspects of the GBM microenvironment are included, the second part of this review focuses on the use of 3D biomaterials to model ECM-related features.Isolated behind the blood–brain barrier (BBB), the brain microenvironment is distinct from that in peripheral tissues. Originating in the brain, GBM tumors closely interact with this unique microenvironment . Even hi6 Da) HA chains act as the organizational center of the ECM, interacting with proteins and PGs through small linker proteins, known as HABPs, to create a hydrogel-like mesh -2-hydroxy-2-methyl-1-propane-1-one) has been commonly used to fabricate biocompatible hydrogels. However, a few recent studies have used phenyl-2,4,6-trimethylbenzoylphosphinate as a more biocompatible alternative, with higher water solubility and more efficient photoactivation than Irgacure 2959 [Since crosslinking does not occur until exposure to light, photochemistries can be used to generate hydrogels with precise spatial and temporal controls. When modeling GBM, photochemical patterning is an attractive strategy for creating gradients of microenvironmental features. Hydrogels are often photo-crosslinked through chain-growth polymerization of acrylates ,45. Moreure 2959 . Use of 2+, are also popular [Noncovalent crosslinks are typically formed via temperature or pH-induced segregation of polymer regions based on hydrophobicity or ionic interactions. Although resultant hydrogels are often weaker than those formed by covalent crosslinks, noncovalent gelation methods are usually more biocompatible. Noncovalently crosslinked hydrogels commonly used for 3D culture include collagen I ,172 and  popular ,165.ex vivo, it is important to control the mechanical properties of 3D scaffolds. In general, mechanical strength of hydrogel scaffolds increases with the crosslinking density  encapsulated in 3D matrices increase migration speed with decreasing scaffold stiffness ,149,153.When using bioactive molecules, such as HA or collagen, as the hydrogel base, controlling scaffold mechanics via polymer concentration means that the biochemical properties are also affected B. As eacTo mimic the biochemical composition of the native brain and GBM tumor microenvironment, 3D hydrogel scaffolds have been fabricated from a variety of ECM-derived biopolymers, including HA ,172, chiAs HA is not generally cell adhesive, gelatin (modified to permit crosslinking with groups such as acrylates) is sometimes added to provide sites for integrin attachment ,45. IncrHybrid scaffolds of HA and collagen I have also been used to investigate the effects of HA on migration of a few patient-derived GBM neurosphere lines ,172. In Nonadhesive PEG ,166 and In addition to whole proteins, such as fibronectin , ECM-derex vivo microenvironments [Growth factors and cytokines can be incorporated into scaffold microenvironments through simple diffusion of solubilized factors, direct chemical conjugation or noncovalent tethering to the hydrogel matrix. Overexpression of EGFR in GBM cell lines, in combination with 3D culture in HA–gelatin hydrogels, upregulated GBM cell (U87MG) expression of MMP-2 and MMP-9 ,45. Furtronments .ex vivo. However, in the majority of 3D experimental models of GBM, the effects of polymer stiffness, ECM concentration and porosity cannot be decoupled. For example, stiffer scaffolds are often fabricated by increasing the concentration of the polymer backbone and/or the density of crosslinks – both of which decrease pore size  was cultured on dextran beads and then embedded into a 3D fibrin hydrogel scaffold . Culturein vivo. In the future, methods for defined, mixed cultures of different GBM cell subtypes  found in heterogeneous tumors would also be valuable – however, identifying culture conditions  that maintain these separate phenotypes and can isolate their individual effects remains a formidable challenge. As an alternative to true cocultures, synthetic peptides that mimic juxtracrine receptors, such as N-cadherin, can be incorporated into biomaterials [Despite these improvements to 3D cocultures methods, we have found no examples of cocultures with patient-derived GBM cells at the time of this review. One challenge to developing cocultures with patient-derived lines is that serum cannot be used without altering GBM cell phenotype . Howeveraterials . Althougex vivo investigations of interactions of GBM tumors with bloods vessels – for example, to study effects of vessel guidance on migration – cocultures of actual vessels formed from endothelial cells  will be required. Recently developed ‘organ-on-chip’ devices, such as the AngioChip® may provide the technology to perform these types of study [in vivo BBB may also be used in the near future to study the interactions of GBM tumors with vasculature structures [To enable of study . ‘Organ-ructures ,192.The most important metric of the value of experimental GBM models is their ability to accurately reflect and predict patient outcomes. Although many improvements have been made over the past 10–15 years , many moThe cells used for any model are crucial to its clinical relevance. Use of patient-derived cells cultured as neurospheres represents a significant improvement over transformed glioma cell lines. However, during neurosphere culture – prior to orthotopic transplantation into a mouse or 3D culture in a biomaterial – these cells lose heterogeneity and, as such, do not accurately reflect the original tumor composition. Recently developed methods for generating GBM organoids  and AVATFurthermore, biomaterial models provide exciting opportunities for personalized medicine. While organoid, xenograft and AVATAR models require weeks to months to establish, biomaterial cultures can be established within days to weeks. Despite the impressive ability of AVATARs to predict patient-specific outcomes ,141, theex vivo experimental platform in which the direct effects of individual microenvironmental parameters on GBM physiology can be studied in a controlled context. Given the complexity of the brain microenvironment, it is often challenging to isolate the contribution of any individual feature to a particular aspect of GBM physiology. Through controlled variation of microenvironmental components, biomaterial platforms can potentially isolate these effects and identify specific therapeutic targets. Robust methods to independently control the presentation of individual features of the GBM microenvironment in a single biomaterial platform would greatly improve the ability of such models to accurately predict clinical outcomes. Researchers are also working to add complexity to biomaterial microenvironments to better mimic the GBM microenvironment, for example, by developing coculture systems with nontumor cells [Engineered, biomaterial-based models provide an or cells ,122 and or cells ,85.in vivo models, it is important to ask how much complexity and which specific features are minimally required to achieve a physiologically relevant model ex vivo? Answering this question will require rigorous evaluation of model fidelity to clinical cases. To achieve this, biomaterial studies will need to include cells from clinically relevant sources, such as patient-derived neurospheres or even freshly biopsied cells. Given the variability across patient samples and GBM subtypes, inclusion of parallel experiments using multiple patient-derived lines would further improve the physiological relevance of results. Although the majority of biomaterial-based studies have focused on invasion, future studies should include equally important GBM tumor features, such as treatment resistance. Finally, model validation will likely require parallel comparisons 3D cultures with patient outcomes  and mouse xenografts. Ideally, cells from the same patient would be studied ex vivo in biomaterials and in vivo as orthotopic transplants and results compared with patient-matched clinical data.As artificial GBM microenvironments have not yet achieved the ability to replace the need for Glioblastoma (GBM) is an extremely lethal brain cancer, with rapid progression and high rates of recurrence.The microenvironment of GBM tumors drives invasion and resistance to treatment.Current experimental models of GBM do not adequately reflect patient outcomes, presenting a challenge to the development of improved treatments.Biomaterial microenvironments can be engineered to mimic multiple aspects of the GBM microenvironment in a controlled manner.Biomaterials can be used as clinically relevant models of GBM to better understand the specific effects of individual features of the microenvironment on tumor physiology and develop new, more effective treatments.


Aeluropus, Mesembryanthemum, Suaeda, Atriplex, Thellungiella, Cakile, and Salicornia serve as a potential candidate for the salt-responsive genes and promoters. Several known genes like antiporters , ion channels , antioxidant encoding genes  and some novel genes such as USP, SDR1, SRP etc. were isolated from halophytes and explored for developing stress tolerance in the crop plants (glycophytes). It is evidenced that stress triggers salt sensors that lead to the activation of stress tolerance mechanisms which involve multiple signaling proteins, up- or down-regulation of several genes, and finally the distinctive or collective effects of stress-responsive genes. In this review, halophytes are discussed as an excellent platform for salt responsive genes which can be utilized for developing salinity tolerance in crop plants through genetic engineering.Halophytes have demonstrated their capability to thrive under extremely saline conditions and thus considered as one of the best germplasm for saline agriculture. Salinity is a worldwide problem, and the salt-affected areas are increasing day-by-day because of scanty rainfall, poor irrigation system, salt ingression, water contamination, and other environmental factors. The salinity stress tolerance mechanism is a very complex phenomenon, and some pathways are coordinately linked for imparting salinity tolerance. Though a number of salt responsive genes have been reported from the halophytes, there is always a quest for promising stress-responsive genes that can modulate plant physiology according to the salt stress. Halophytes such as  Salinization is a worldwide problem in which salts gradually accumulate in the soil. In this process, water-soluble salts are deposited in the soil to an extent that affects crop productivity, microbial community, and agricultural economics FAO, . The salHalophytes are salt-resistant or salt-tolerant plants and have remarkable ability to complete their life cycle in saline condition. During evolution, they have developed different morphological, anatomical, and physiological strategies to proliferate in high-salt environments  are extreme halophytes and best adapted to high salinity conditions. Halophytes such as Atriplex, Bassia, and Camphorosma are not strictly related to increased salinity, therefore may be classified as reversible halophytes. There is always a difficulty with the distinct terminology of halophytes because the definition is still obscure and Grigore et al. , vacuolar pyrophosphatase, potassium transporters, ion channels, antioxidants, ROS scavengers, and proteins that involve in protective function and signal transduction. Additionally, some novel salt responsive genes were also cloned and characterized from halophytes like S. brachiata  and one silencer region (located between −890 and −641).A strong and well-regulated promoter is required for the engineering of crop plants to achieve the desired level of expression of a transgene. A comparative transcriptome analysis revealed that many stress-related genes constitutively expressed at higher level in SlBADH gene promoter fragment (−300 bp only) from Suaeda liaotungensis showed about 6.3-fold expression under salt stress (400 mmol/l NaCl) compared to control (non-stressed) condition  showed an 18.6-fold increase in the GUS activity under NaCl stress (200 mmol/l) treatment  have a different specificity of regulation and stress induction in rice. Sun et al.  which enhances the expression of GUS in transgenic Arabidopsis under salt stress. The CBL1 gene promoter isolated from Ammopiptanthus mongolicust controlled the expression of the reporter gene under abiotic and biotic stress conditions  showed the presence of enhancer and repressor binding sites in the cis-regulatory elements along with stress-inducible motifs , under the control of non-specific CaMV35S promoter, showed tolerance in the range of 150–250 mM NaCl, however their halophytic homologs may provide tolerance up to 400 mM NaCl , GhNHX1 (Gossypium hirsutum), and HbNHX1 (Hordeum brevisubulatum) have demonstrated to produce salt tolerance in the model plant tobacco  showed 75% amino-acid sequence similarity with AtNHX1  and a higher salinity tolerance in Oryza sativa , SaNHX1 (Spartina anglica) or SsNHX1  gene show tolerance up to 300–400 mM NaCl compared to glycophytic counterparts  in the transgenic plants compared to their glycophytic homologs  from halophyte S. brachiata in the transgenic plants  from A. littoralis improves different abiotic stress tolerance in tobacco, wheat, and rice  or TsHKT1  were analyzed and delayed root growth was observed in AtHKT1 compared with those expressing TsHKT1 (Ali et al., AtHKT1. They also demonstrated a strong salt-dependent up-regulation of TsHKT1 but a strong repression of AtHKT1 expression under salt stress (Ali et al., A comparative transcript expression analysis revealed a higher expression of antiporter Based on different reports, it may be concluded that halophytic genes are one of the promising candidates to be explored further for producing transgenic plants with a higher level of salt tolerance as compared to glycophytic counterpart genes. Further, halophytes also serve as valuable resources to discover novel abiotic stress responsive genes for improving stress tolerance of crop plants for sustainable agriculture in the saline affected areas.Halophytes are more tolerant to abiotic stress because of high differential regulation of the same basic set of stress-responsive genes present among all plants. Furthermore, halophytes exhibited higher expression of a large number of stress-inducible genes under the non-stress condition, suggesting constitutive expression of genes in halophytes. Since different halophytes use different mechanisms to respond the salt stress, a single species cannot be considered as a model species. However, the emergence of a halophyte species as a model plant for the molecular elucidation of corresponding abiotic stress tolerance will enlighten our understanding of the salinity tolerance mechanisms. Identification and isolation of novel salt responsive genes and promoters from different halophytes can be explored for the genetic engineering of crop plants for abiotic stress tolerance using transgenic approach.AM: Conceived the idea, collected literature and wrote the paper. BT: Helped in revisions. All authors approved this mini-review for the 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.


Rodent studies have recently demonstrated substantial integration of transplanted photoreceptors, with potential synaptic connection and functional restoration. Consequently, photoreceptor transplantation therapy for retinitis pigmentosa is attracting a growing interest in the field of translational research. Differentiation strategies for the formation of three-dimensional (3D) retinal tissue that are suitable for graft preparation have also been introduced via the use of human embryonic stem cells (hESCs) and human induced pluripotent stem cells. We have recently shown that hESC-derived retinal tissue (hESC-retina) can survive, mature, and potentially integrate with host secondary neurons following transplantation into two established primate models of retinal degeneration. Our data demonstrated the feasibility of deploying hESC-retina transplantation as a new remedy with which to restore the vision of patients with end-stage retinal degenerative diseases. In the present mini-review, we provide a short introduction of photoreceptor transplantation research. The retina is composed of three layers of neurons, with photoreceptor cells located in the outermost layer. There are two types of photoreceptors, rods and cones, which respond to light and transfer signals to the inner neurons Fig. . RetinitOver the last decade, a number of studies in rodents have led to substantial progress being made in photoreceptor transplantation. MacLaren et al. showed that during late ontogenetic stages, photoreceptor precursors can integrate, differentiate into rod photoreceptors, form synaptic connections, and improve visual function upon transplantation into wild-type mice and mice models of early RP . SubsequAlthough the efficacy of retinal tissue transplantation has been demonstrated in rodent studies, it has until recently remained unclear whether similar results can be achieved in primate models and human tissue grafts in terms of host acceptability and graft competency. We have recently evaluated this issue in a step by step manner . We firsIn this mini-review, we provide a brief introduction of the current status of photoreceptor transplantation. Further research is now required to investigate whether hESC-derived retinal grafts are indeed functionally integrated. However, continued progress in this exciting discipline would finally make it possible for us to restore vision in RP patients by transplanting retinal tissue.Not applicable.Not applicable.Not applicable.


Liver cancer is now considered the sixth most prevalent malignancy and the second leading cause of cancer-related mortality in the world. In particular, hepatocellular carcinoma (HCC) is the most frequent liver cancer subtype, representing around 90% of all cases . Unlike The development of new drugs is an arduous task that starts with the identification of the candidate targets. In principle, the ideal cancer target should only impact the survival and fitness of the cancer cells but spare the normal ones. One option is to focus the efforts on targeting cancer driver genes, which actively promote cancer progression and whose inhibition can lead to tumor reduction. Since many known cancer drivers are in practice undruggable, one alternative is to aim at targeting key mediators of those driver genes, as their repression should in theory render similar effects. Another possibility is to inhibit synthetic lethal targets, a strategy that is only effective in the presence of a particular genetic alteration present in the cancer cells . To systRNAi screens have been used for this purpose during the last decade with satisfactory results. Unlike “genome-wide” screens, which are usually tedious, expensive, and hard to analyze and reproduce, “targeted” screens, focused on specific pathways or cellular processes, have emerged as a more convenient alternative for drug target discovery in cancer. One of the earliest studies successfully exploiting this concept was performed in acute myeloid leukemia. By using a customized short hairpin RNA (shRNA) library targeting 243 known chromatin regulators, BRD4 (Bromodomain-containing protein 4) was identified as a promising drug target , providiin vivo CRISPR screen unmasked four novel tumor suppressor genes  that are negative regulators of the MAP kinase pathway, indicating that drugs targeting the pathway could be successful in treating HCC patients harboring mutations in any of the four genes [More recently, CRISPR technology has been adapted for its use in high-throughput genetic screenings. Pioneering works have confirmed the high sensitivity of CRISPR-based libraries to identify essential genes in human cancer cell lines , highligur genes .Despite the very promising prospects that these technologies exhibit, there are still some obstacles that may hinder the identification of patient-specific targets in HCC. On one hand, both types of technologies present some limitations. For instance, RNAi leads to incomplete target inhibition and produces significant off-target effects, contributing to false negative and false positive results, respectively. Furthermore, while CRISPR technology seems to overcome these drawbacks, it also induces double strain breaks in the DNA, which trigger genotoxic stress and limit its use for targeting highly amplified loci (very frequent in cancer cells) . In this


Tobacco smoking and smoke exposure during pregnancy and childhood cause considerable childhood morbidity and mortality. We did a systematic review and meta-analysis to investigate whether implementation of WHO's recommended tobacco control policies (MPOWER) was of benefit to perinatal and child health.We searched 19 electronic databases, hand-searched references and citations, and consulted experts to identify studies assessing the association between implementation of MPOWER policies and child health. We did not apply any language restrictions, and searched the full time period available for each database, up to June 22, 2017. Our primary outcomes of interest were perinatal mortality, preterm birth, hospital attendance for asthma exacerbations, and hospital attendance for respiratory tract infections. Where possible and appropriate, we combined data from different studies in random-effects meta-analyses. This study is registered with PROSPERO, number CRD42015023448.We identified 41 eligible studies  that assessed combinations of the following MPOWER policies: smoke-free legislation (n=35), tobacco taxation (n=11), and smoking cessation services (n=3). Risk of bias was low in 23 studies, moderate in 16, and high in two. Implementation of smoke-free legislation was associated with reductions in rates of preterm birth , rates of hospital attendance for asthma exacerbations , and rates of hospital attendance for all respiratory tract infections  and for lower respiratory tract infections . Associations appeared to be stronger when comprehensive smoke-free laws were implemented than when partial smoke-free laws were implemented. Among two studies assessing the association between smoke-free legislation and perinatal mortality, one showed significant reductions in stillbirth and neonatal mortality but did not report the overall effect on perinatal mortality, while the other showed no change in perinatal mortality. Meta-analysis of studies on other MPOWER policies was not possible; all four studies on increasing tobacco taxation and one of two on offering disadvantaged pregnant women help to quit smoking that reported on our primary outcomes had positive findings. Assessment of publication bias was only possible for studies assessing the association between smoke-free legislation and preterm birth, showing some degree of bias.Smoke-free legislation is associated with substantial benefits to child health. The majority of studies on other MPOWER policies also indicated a positive effect. These findings provide strong support for implementation of such policies comprehensively across the world.Chief Scientist Office Scotland, Farr Institute, Netherlands Lung Foundation, Erasmus MC. Almost half of children worldwide are regularly exposed to second-hand smoke, and 28% of the 600 000 deaths each year related to second-hand smoke occur in children.9PanelMonitor tobacco useEligible policies include those that enforce accurate measurement of the extent of the tobacco epidemic and of the interventions to control it.Protect people from smokeEligible policies include legislation to create smoke-free public environments (both indoors and outdoors).Offer help to quit tobacco useEligible policies include tobacco cessation advice or interventions offered through health-care services, free telephone quit lines, and providing access to free or low-cost cessation medicines.Warn about the dangers of tobaccoEligible policies include health warnings on tobacco products, plain packaging of tobacco products, and mass media campaigns to educate the public about the dangers of tobacco.Enforce bans on tobacco advertising, promotion and sponsorshipSee WHO Framework Convention on Tobacco Control (FCTC) guidelines for implementation of Article 13, which provides a non-exhaustive list of advertising, promotion, and sponsorship within the terms of the FCTC.Raise taxes on tobaccoEligible policies include increasing percentage excise tax share in final tobacco.Protection of children from the adverse health implications of second-hand smoke during important phases of development and the subsequent disease burden carried on into adulthood is crucial. The WHO Framework Convention on Tobacco Control (FCTC) aims to reduce tobacco consumption and second-hand smoke exposure through national tobacco control programmes.14Evidence before this studyTobacco smoke exposure is the world's leading cause of preventable morbidity and premature mortality. Children cannot control their tobacco smoke exposure and therefore need protection through tobacco control measures. In a previous systematic review, we investigated the associations between smoke-free legislation and perinatal and child health outcomes. We searched 14 online medical research databases, the WHO International Clinical Trials Registry Platform, hand-searched references and citations, and consulted a Added value of this studyTo our knowledge, this is the first systematic review examining the association between the full spectrum of MPOWER policies and perinatal and child health. Our findings add value to the existing evidence base by identifying a link between smoke-free legislation and a substantial reduction in severe paediatric respiratory tract infections, providing consistent evidence that comprehensive smoke-free laws are associated with broad health effects, and collating evidence supporting the potential for other MPOWER measures to benefit child health. We also identified several key knowledge gaps, including a shortage of studies in low-income and middle-income countries, and of studies assessing MPOWER measures other than smoke-free legislation, tobacco tax increases, and smoking cessation services.Implications of all the available evidenceWith most of the world's population currently not covered by comprehensive tobacco control policies, there is great potential for global public health gains by protecting unborn babies and children from tobacco smoke exposure. Future efforts should focus on increasing the uptake of comprehensive MPOWER policies worldwide to protect the health of children, while developing and evaluating new and ongoing tobacco control policy initiatives around the world.In a previous systematic review,This systematic review and meta-analysis was done according to a peer-reviewed protocol that is publishedStudies were eligible for inclusion if they investigated the association between one or more MPOWER tobacco control policies and health outcomes among fetuses, neonates, or children .We searched for published studies in the following databases: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, PsycINFO, Cumulative Index to Nursing and Allied Health Literature (CINAHL), WHO Global Health Library , IndMED, ISI Web of Science, KoreaMed, EconLit, Paediatric Economic Database Evaluation (PEDE), Google Scholar, and the ProQuest database of PhD dissertations. We searched the WHO International Clinical Trials Registry Platform (ICTRP) for unpublished studies.The We focused on studies that evaluated governmental public health interventions that could be classified according to the MPOWER acronym , with thTwo reviewers (TF and AK) independently assessed all search results by title and abstract, and by full text for potential eligible studies identified. Any disagreements were resolved through joint discussion or via an adjudicator (JVB).Relevant data were extracted with a customised data extraction form . Study aA risk-of-bias assessment form was created on the basis of EPOC criteria for interrupted time series and controlled before-and-after studies.Point estimates and corresponding 95% CIs for effect sizes or association measures were extracted. For dichotomous outcomes, risk ratios (RRs) were extracted. Where RRs were not available, we calculated RRs from odds ratios (ORs) using the following formula, where PEER is the patient-expected event rate in the control group:When PEER was not available in interrupted time series studies we used the overall event rate across the study population as an approximation. For outcomes that could occur more than once , we used incidence rate ratios (IRRs).I2 statistic. For the meta-analyses, we selected the effect estimate of the most comprehensive intervention within each MPOWER category from each study. In case of overlapping populations between studies, we selected one study according to the following hierarchy: the lowest risk of bias, the most comprehensive intervention, or the largest study population. We also extracted data on changes in smoking behaviour and second-hand smoke exposure if reported. The comprehensiveness of smoke-free legislation was assessed by counting the number of locations that were made completely smoke-free, out of eight prespecified options as suggested by WHO.Aggregated effect estimates were calculated to assess the association between each tobacco control policy and individual health outcomes, where feasible. Relative risk differences were extracted or calculated from absolute risk differences and were pooled in random-effects meta-analyses given anticipated heterogeneity. Step changes  following introduction of an intervention were pooled in separate analyses from slope changes . Heterogeneity was assessed by the We did sensitivity analyses to explore the robustness of our findings by reanalysing the data for the primary outcomes with the addition of non-EPOC studies, and by restricting analyses to studies with low risk of bias and moderate risk of bias. Where possible, we did subgroup analyses according to the comprehensiveness of each intervention. Where possible, the effect of each intervention was reported according to socioeconomic status, alongside its overall effect.We assessed risk of bias across studies using funnel plots when ten or more studies were included in a meta-analysis.The funders of the study had no role in study design, data collection, data analysis, data interpretation, or writing of the report. The corresponding author had full access to all the data in the study and had final responsibility for the decision to submit for publication.We identified 25 478 citations from bibliographic databases and an additional 20 from other sources. After removal of duplicates, 12 392 unique citations were screened by title and abstract, and 65 full texts were sourced. Of these, 41 EPOC studiesThe 61Risk of bias of individual studies is reported in detail in the 28 studies assessed the association between smoke-free legislation and one or more primary outcomes , five assessed the association between tobacco taxation and primary outcomes, and two assessed the association between policies providing smoking cessation services and our primary outcomes , Table 3A national study from the Netherlands, comprising 1 980 727 births, found no change in perinatal mortality following a law to prohibit smoking in workplaces and on public transport, or following expansion of the law to include restaurants and bars.15 studies investigated the association between smoke-free legislation and preterm births.Associations between smoke-free legislation and the incidence of hospital attendances for childhood asthma were reported in ten studies .18, 36, The association between smoke-free legislation and the incidence of hospital admissions for acute respiratory tract infections was reported in four studies .16, 18, We did not identify any studies assessing the effect of other MPOWER policies on child health.In sensitivity analyses, inclusion of non-EPOC studies in the meta-analyses or restriction of the primary analyses to studies with low to moderate risk of bias did not materially change the effect estimates for smoke-free legislation and our primary outcomes .Point estimates for the association between smoke-free legislation and our primary outcomes were generally much larger when subgroup analyses were restricted to studies assessing comprehensive smoke-free laws than when studies assessing partial smoke-free laws were analysed (preterm birth: seven studies, 9 355 359 individuals, −5·12% [95% CI −7·24 to −2·99]; hospital attendances for asthma: four studies, 556 019 events, −12·49% [–19·78 to −5·20]; 11 studies assessed whether the association between implementation of tobacco control policies and child health varied according to indicators of socioeconomic status .16, 29, 27 studies assessed the association between tobacco control policies and secondary outcomes . In the This systematic review and meta-analysis provides considerable evidence indicating child health benefits associated with implementation of MPOWER policies. By pooling data of 27·5 million births, 685 000 hospital admissions for asthma, and 2·3 million hospital admissions for respiratory tract infections, we found a 3·7% reduction in preterm births, a 9·8% reduction in childhood hospital admissions for asthma, and an 18·5% reduction in hospital admissions for lower respiratory tract infections following implementation of smoke-free legislation. Subgroup analyses suggested that health benefits were increased when the most comprehensive laws were applied. We also identified several studies indicating that tobacco tax increases and governmental support for smoking cessation services could benefit child health. Taken together with substantial existing evidence on the effectiveness of tobacco control policies in improving adult health, these findings provide strong support for implementation of such policies comprehensively across the world.This study is, to our knowledge, the most comprehensive assessment done to date of the effect of tobacco control policies on perinatal and child health outcomes. On the basis of our previous work,However, our study has some limitations. The risks of residual confounding and bias in quasi-experimental studies—due to non-random allocation of the intervention and the absence of a control group—need to be considered when interpreting the results.This study adds to our previous work.Socioeconomic disparities in smoking and related morbidity are widely documented and affect both adults and children. For example, such disparities were estimated to account for 38% of the inequality in stillbirths and 31% of the inequality in infant deaths in Scotland.Given the inherent restrictions in attributing causality from quasi-experimental studies, it is important to interpret the findings in light of circumstantial evidence supporting the link between tobacco control policies and child health benefits. We have previously described the main likely causal pathways.The global health burden of tobacco use is tremendous and its total global economic cost is estimated to be around USD$1·4 trillion.Reports indicate that at least two of five people living in low-income and middle-income countries remain unprotected by any MPOWER policy measure,In conclusion, given the positive findings of this systematic review it is crucial that the uptake of comprehensive tobacco control policies is accelerated worldwide to further protect children from the health hazards of tobacco smoke exposure,


Immune cell function and metabolism are closely linked. Many studies have now clearly demonstrated that alterations in cellular metabolism influence immune cell function and that, conversely, immune cell function determines the cellular metabolic state. Less well understood, however, are the effects of systemic metabolism or whole organism nutritional status on immune cell function and metabolism. Several studies have demonstrated that undernutrition is associated with immunosuppression, which leads to both increased susceptibility to infection and protection against several types of autoimmune disease, whereas overnutrition is associated with low-grade, chronic inflammation that increases the risk of metabolic and cardiovascular disease, promotes autoreactivity, and disrupts protective immunity. Here, we review the effects of nutritional status on immunity and highlight the effects of nutrition on circulating cytokines and immune cell populations in both human studies and mouse models. As T cells are critical members of the immune system, which direct overall immune response, we will focus this review on the influence of systemic nutritional status on T cell metabolism and function. Several cytokines and hormones have been identified which mediate the effects of nutrition on T cell metabolism and function through the expression and action of key regulatory signaling proteins. Understanding how T cells are sensitive to both inadequate and overabundant nutrients may enhance our ability to target immune cell metabolism and alter immunity in both malnutrition and obesity. Nutritional imbalance is a major challenge for living organisms to achieve systemic homeostasis and maintain normal physiology. Mammals have developed processes to control systemic nutrient utilization and storage. For example, excess nutrients are converted and stored in adipose tissue, liver, and muscle during times when nutrients are abundant. By contrast, stored nutrients are metabolized to provide energy and building blocks to maintain vital physiological processes when nutrient availability is low.From these processes, adipose tissue volume changes in response to under- or overnutrition. This change in adipose tissue volume, in turn, influences the secretion of hormones and cytokines from adipose tissue (adipocytokines). Many of these adipocytokines have important immune signaling functions which can influence immune cell biology and alter immune response.Here, we will review the effects of nutritional changes on hormones and cytokines that influence immune cell function and metabolism in mouse models, and we will specifically examine how nutritionally regulated changes in immune cells alter immunity in the context of both autoimmune disease and infection response in both human and animal studies. We will also highlight some of the promising metabolic targets that may be useful in the development of novel treatments for immunity-related disorders.Many cytokines and hormones are changed in response to over- or undernutrition. One of the earliest reports of this is with tumor necrosis factor-alpha (TNF-α). TNF-α can be secreted from adipose tissue, and its expression is increased during obesity but decreased following weight loss –3. TNF-αInterleukin-6 (IL-6) is another cytokine that is secreted by many immune and non-immune cells in the adipose tissue including adipocytes, macrophages, pre-adipocytes, and T cells, in response to tissue damage . IL-6 haLeptin is another well-described adipocytokine known to influence immune cells. Leptin is a hormone secreted by adipocytes in proportion to adipocyte mass and is therefore increased in obesity and decreased in malnutrition. Leptin is best known for its role in influencing systemic metabolism by signaling in the hypothalamus to suppress appetite and increase energy expenditure . HoweverIn addition to TNF-α, IL-6, and leptin, many other hormones and cytokines are influenced by changes in systemic metabolism and are summarized in Table The hormone and cytokine changes seen in response to obesity and malnutrition are closely linked to changes in immune cell populations. Several types of immune cells residing in the adipose tissue are affected by changes in the above-listed cytokine and hormone levels and in turn contribute to altered cytokine production in states of under- or overnutrition. These adipose tissue-localized immune cells can be affected by changes in nutritional status through both paracrine effects (due to their proximity to adipocytes) and systemic/endocrine effects of secreted adipose factors.Macrophages comprise more than 50% of adipose tissue-resident immune cells and are, therefore, the most abundant immune cells in the adipose tissue . During In addition to macrophages, other smaller populations of innate immune cells are found in the adipose tissue and change in number and function in response to obesity. Neutrophils and mast cells are found to increase and become activated in the adipose tissue during obesity . By contSeveral lymphocyte populations are also found in the adipose tissue. B lymphocytes (B cells) have been found to accumulate in the adipose tissue during obesity . AlthougT lymphocytes (T cells) represent the most abundant lymphocyte population and second most abundant immune cell in the adipose tissue behind macrophages . Both CDDuring normal physiological conditions, the adipose tissue represents a major depot of Treg cells in the body , 67. Thedecrease in immune cell number. This has been shown particularly in the case of T cells: mice fasted 48 h had large and significantly decreased thymocyte and splenocyte counts compared to fed control mice /Akt pathway, which is partially responsible for the upregulation of a glycolytic metabolic program , 86. The0 and enter the rapid expansion phase of the immune response. This has been confirmed in a T cell specific knockout of c-Myc, in which T cells fail to proliferate and were unable to upregulate glycolytic metabolism , and pyruvate kinase muscle isozyme 2 . Glut1 itabolism . c-Myc atabolism . HIF-1-αtabolism , 98. HIFDifferentiation of CD4+ T cells into functionally distinct subsets is associated with alterations in the cellular metabolic phenotype. In general, Teff cells are pro-glycolytic and depend heavily upon an increased glucose uptake, as well as glutamine metabolism, to fuel effector function, as described above. Inhibition of glycolysis prevents differentiation into these pro-inflammatory subsets . RegulatThe first evidence of T cell differentiation depending on metabolism came from studies using the drug rapamycin. Treatment with rapamycin prevented T cell growth and proliferation and promoted differentiation of Treg cells, rather than Teff cells . FurtherNot only does the activity of mTORC1 promote Teff cell differentiation over Treg cells but differential activity of mTORC1 and mTORC2 promotes distinct Teff subsets , 98, 105ad libitum fed mice. The functional and metabolic defects of Th17 cells were restored when fasted mice received leptin injections or when T cells isolated from fasted mice were activated in the presence of leptin in vitro. Leptin can affect many types of immune system; however, these effects of leptin on T cells were shown to be cell-intrinsic, as Th17 cells from T cell-specific LepR conditional knockout mice showed a decreased glucose uptake and glycolysis as well as a decreased glycolytic enzyme expression, whereas glucose metabolism and function of Treg cells from T cell-specific LepR conditional knockout mice were unaffected. Altogether, these studies show that leptin is a systemic hormone that communicates nutritional status to immune cells by directly increasing Teff cell glucose metabolism and thereby fueling Teff cell function.One well-established connection between systemic nutritional status and immune cell metabolism is through leptin. As mentioned above, leptin is secreted by adipocytes in proportion to adipocyte mass and leptin levels, thereby trending with nutritional status . In statThe effect of leptin on immune cells is now well documented; however, other nutritionally regulated hormones may also mediate the communication between systemic nutritional status and immune cell function. One such candidate hormone is insulin. Insulin is secreted from pancreatic beta cells following an increase in blood glucose; however, insulin levels also become elevated in states of obesity due to insulin resistance of metabolic tissues including muscle and adipose tissue. Insulin is best known for its role in promoting glucose uptake and glycolysis in metabolic tissues through its ability to upregulate surface expression of the glucose transporter Glut4 and increase the activities of the glycolytic enzymes hexokinase and phosphofructokinase –116. InsGiven the role of leptin in regulating the balance between Teff and Treg cells, multiple studies have examined the effect of leptin on autoimmune diseases. One well-studied example is the autoimmune disease multiple sclerosis (MS). The autoimmunity of MS depends upon the activation of Teff, particularly Th1 and Th17 cells, which produce inflammatory cytokines that promote inflammation. Conversely, Treg cells influence immune response by suppressing inflammation caused by Teff and other inflammatory immune cells and thereby protect against autoimmunity. The balance of Teff  to Treg cells in MS is, therefore, a critical determinant of inflammation and autoimmune disease. Multiple human studies have shown that active MS is associated with a decreased Treg cell number and proliferation –121.Nutritional status appears to influence MS susceptibility. Clinical studies have shown an association between adolescent obesity and an increased risk of developing MS, particularly in women –125. ConThe role of leptin in promoting T cell inflammation has also been well described in a mouse model of MS, experimental autoimmune encephalomyelitis (EAE). Serum leptin levels have been shown to be increased in EAE and correlate with disease severity , 129. EaSince leptin levels decrease with fasting and calorie restriction, the effect of fasting on EAE disease severity has been examined by several groups. Fasting-induced hypoleptinemia resulted in a reduced EAE disease severity , 133. ThLeptin signaling has also been implicated in several other autoimmune diseases. In systemic lupus erythematosus (SLE), leptin levels have been reported to be elevated in human patients and correlate with severity in a mouse model of the disease , 135. DeStreptococcus pneumonia and gastrointestinal infections , which is an allosteric activator of 6-phosphofructo-1-kinase: a rate-limiting enzyme in the glycolysis pathway that phosphorylates fructose 6-phosphate (F6P) to yield fructose 1,6-bisphosphate . The inte enzyme . PFKFB3 e enzyme , 171. Inammation . SimilarMost activated immune cells are dependent on glycolysis for the rapid generation of energy, which limits the flow of pyruvate to the TCA cycle. However, TCA cycle intermediates are essential for proliferation and immune cell functions, and activated immune cells generally overcome this by metabolizing amino acids. This requires the upregulation of many genes involved in amino acid transport and catabolism.Branched-chain aminotransferase (BCAT) is the enzyme responsible for the transamination of branched-chain amino acids (BCAAs): leucine, isoleucine, and valine. There are two isoforms of the BCAT enzymes: cytosolic BCAT1 and mitochondrial BCAT2. Transamination of BCAAs is the initial reaction toward the formation of branched-chain α-keto acids, which are decarboxylated to produce coenzyme A (CoA) derivatives . LeucineBranched-chain aminotransferase 2 is highly expressed in many tissues including the kidneys, skeletal muscle, and tissues of the digestive system, while BCAT1 is expressed in a small number of tissues including placenta, adult brain, peripheral neurons, and a limited number of embryonic tissues . BCAT1 wIn contrast to acutely activated T cells being dependent on glycolysis, chronically activated T cells involved in autoimmune disease are more dependent on oxidative phosphorylation for energy production –178. ThiChanges in nutritional status have a wide range of effects on the body, which can influence organ size, hormone, and cytokine levels, and immune cell populations and function. This link between nutrition and immunity is mediated, in part, by a select group of adipocytokines, such as leptin, which can influence immune cell number and function through its effects on cellular metabolism Figure . For thaAll authors participated in the writing of this manuscript.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.


Spinal cord injury (SCI) is an intractable and worldwide difficult medical challenge with limited treatments. Neural stem/progenitor cell (NS/PC) transplantation derived from fetal tissues or embryonic stem cells (ESCs) has demonstrated therapeutic effects via replacement of lost neurons and severed axons and creation of permissive microenvironment to promote repair of spinal cord and axon regeneration but causes ethnical concerns and immunological rejections as well. Thus, the implementation of induced pluripotent stem cells (iPSCs), which can be generated from adult somatic cells and differentiated into NS/PCs, provides an effective alternation in the treatment of SCI. However, as researches further deepen, there is accumulating evidence that the use of iPSC-derived NS/PCs shows mounting concerns of safety, especially the tumorigenicity. This review discusses the tumorigenicity of iPSC-derived NS/PCs focusing on the two different routes of tumorigenicity (teratomas and true tumors) and underlying mechanisms behind them, as well as possible solutions to circumvent them. Spinal cord injury is a devastating neurological condition, which results in the disruption of signals between the brain and body yielding severe physical, psychological, and social dysfunction , 2. PatiOriginally, glucocorticoid drugs like methylprednisolone were regarded as the classic therapeutic treatment for SCI , as theyRecent progress in cell transplantation has opened up new opportunities to understand and treat SCI. Among the several types of candidate cells, NS/PC holds great therapeutic potential for SCI, as it can replace the lost neurons and glia as well as create a growth-promoting environment . NeverthIn 2006, Takahashi and Yamanaka showed that fibroblasts from mouse somatic cells could regain pluripotency after expressing four transcriptional factors , thus deOf late, an increasing number of research groups have applied iPSCs to SCI and achieved interesting results . In 2010There are also some negative reports on iPSC approaches to SCI. Two reports revealed that despite the ability to differentiate into neural cells , 22, iPSTumorigenicity of any stem cell transplants remains a major concern for clinical applications, and there is an urgent need for it to be addressed before translation of iPSC techniques into SCI treatment. From several reports , 27, tumTeratoma is a relatively common potential risk in grafts of iPSCs especially when individual iPSC clones were preevaluated as unsafe , 17, 28.It is still unclear why undifferentiated cells remain in iPSC grafts. However, iPSC derivatives of different origins do demonstrate different teratoma-forming propensity , 28. ForSeveral studies have found that even if all undifferentiated cells are purged , 34, iPSβ-catenin signaling pathway [The exact mechanism underlying iPSC tumorigenesis is still not clearly defined, but several factors are thought to contribute to it. Collectively, genomic and epigenomic instability correlates largely with tumorigenicity of iPSCs , 36. Man pathway . This pa pathway . Also, tOn the other hand, epigenomic instability, especially DNA methylation, also plays a role in the formation of true tumors . DNA metIncreased number of passages to weaken epigenetic memory. Several studies observed the loss of epigenetic memory with increased passage number , 39. iPSTake advantage of epigenetic memory characteristics and use it to reprogram iPSCs away from a teratoma-inducing lineage. The propensity of iPSCs to differentiate bias into their starting cell lineage could be exploited to produce certain cell types. For example, to get more NS/PCs from iPSCs, we may ideally think of the utilization of neural cells. Some previous reports , 41 alsoImprove the ability to purify iPSC-NS/PCs. It is essential to better gain bona fide iPSC-NS/PCs, as the potential for contamination with undifferentiated iPSCs presents a big chance of forming teratomas. Therefore, scientists have tried many ways to achieve the common goal including finding more specific cell surface makers and diminishing residual undifferentiated cells like inhibiting DNA topoisomerase II or stearoyl-coA desaturase , 42. AccTransplant more mature cells instead of naive ones. It has been observed that teratomas formed from iPSC-derived NS/PCs were much smaller than those directly from iPSCs, indicating that predifferentiation of iPSCs can reduce certain aspects of tumorigenicity . ConsequAs mentioned above, the formation of teratomas is largely attributed to undifferentiated cells. Based on this, some reports proposed various methods to address this problem including the following:Taken together, these ways to address undifferentiated cell contamination in iPSC-derived NS/PC transplants are, at least in part, currently effective, but it seems impossible for some of these methods to be translated into clinical application due to either the invasive operation or time-consumed culture to weaken epigenetic memory. And we had better transplanted relatively mature iPSC-derived NS/PCs instead of iPSC itself.Change the reprogramming methods into integration-free methods. Virally induced iPSCs with genomic integrations of transcriptional factors easily cause insertional mutagenesis and result in continual expression of residual factors in iPSCs . Thus, iAvoid using transgenic factors of oncogenesis. The Yamanaka factors are competent enough to induce tumorigenesis playing important roles in the development and maintenance of cancer. It appears quite necessary to reduce reprogramming factors in order to decrease the possibility of tumor formation and hasten the clinical use. Nakagawa et al. initiated a series of experiments to test whether fewer factors are capable enough of inducing the stem cell. It was found that exogenous c-Myc was not necessarily needed to generate iPSCs . They thReduce undesirable DNA methylation. Decreasing DNA methylation of tumor suppressor genes and increasing that of oncogenes can certainly reduce the rate of tumor formation from iPSCs. The application of knocking down the maintenance methyltransferase DNMT1 or the demethylating agent like 5-AZA can reduce residual methylation of resulting cells and convert them to authentic pluripotent cells . BesidesEstablish reliable ways to distinguish the safe and unsafe cell clones. By virtue of the teratoma-forming activity of the iPSC derivatives after their transplantation , we are As for substantial tumors, we also have several effective steps to reduce the risk including the following:In brief, across the entire process of iPSC generation and NS/PC differentiation, there are steps that can be taken to reduce nonteratoma tumor formation. These strategies mentioned above just provide some possible way to circumvent the tumorigenicity, but I am afraid that there is still a long way from clinical applications.Despite numerous therapeutic discoveries in the laboratory, to our knowledge, faithfully effective treatment for spinal cord injury remains unavailable. iPSC transplantation for SCI is currently an unrealistic strategy, but we have already recognized the huge potential of iPSCs for SCI because of their ability to self-renew and differentiate into various types of neural cells. In addition, iPSCs also avoid the ethical issues associated with some transplant sources and importantly can be performed in an autologous manner removing the need for immune suppression.However, although the Takahashi group claimed that they were warranted to restart their clinical trials on iPSCs, safety concerns, especially tumorigenicity, still seriously limit considerations for clinical application, at least on SCI . They on