Dental pulp stem cells immobilized in alginate microspheres for applications in bone tissue engineering.
AIM
To immobilize dental pulp stem cells (DPSC) in alginate microspheres and to determine cell viability, proliferation, stem cell characteristics and osteogenic potential of the immobilized DPSCs.


METHODOLOGY
Human DPSCs isolated from the dental pulp were immobilized in 1% w/v alginate microspheres. Viability and proliferation of immobilized DPSCs were determined by trypan blue and MTT assay, respectively. Stem cell characteristics of DPSCs post immobilization were verified by labelling the cells with CD73 and CD90. Osteogenic potential of immobilized DPSCs was assessed by the presence of osteocalcin. Alizarin red staining and O-cresolphthalein complexone method confirmed and quantified calcium deposition. A final reverse transcriptase PCR evaluated the expression of osteogenic markers - ALP, Runx-2 and OCN.


RESULTS
More than 80% of immobilized DPSCs were viable throughout the 3-week study. Proliferation appeared controlled and consistent unlike DPSCs in the control group. Presence of CD73 and CD90 markers confirmed the stem cell nature of immobilized DPSCs. The presence of osteocalcin, an osteoblastic marker, was confirmed in the microspheres on day 21. Mineralization assays showed high calcium deposition indicating elevated osteogenic potential of immobilized DPSCs. Osteogenic genes- ALP, Runx-2 and OCN were also upregulated in immobilized DPSCs. Surprisingly, immobilized DPSCs in the control group cultured in conventional stem cell media showed upregulation of osteogenic genes and expressed osteocalcin.


CONCLUSION
Dental pulp stem cells immobilized in alginate hydrogels exhibit enhanced osteogenic potential while maintaining high cell viability both of which are fundamental for bone tissue regeneration.
['Kanafi|M M|MM|', 'Ramesh|A|A|', 'Gupta|P K|PK|', 'Bhonde|R R|RR|']
D000464:Alginates D001846:Bone Development D049109:Cell Proliferation D002478:Cells, Cultured D003782:Dental Pulp D020723:Glucuronic Acid D006603:Hexuronic Acids D006801:Humans D008863:Microspheres D020133:Reverse Transcriptase Polymerase Chain Reaction D013234:Stem Cells D023822:Tissue Engineering
dental pulp stem cells immobilization microspheres bone tissue engineering alginate hydrogels