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Title: Devitalized Stem Cell Microsheets for Sustainable Release of Osteogenic and Vasculogenic Growth Factors and Regulation of Anti‐Inflammatory Immune Response

The objective of this work is to investigate the effect of devitalized human mesenchymal stem cells (hMSCs) and endothelial colony‐forming cells (ECFCs) seeded on mineralized nanofiber microsheets on protein release, osteogenesis, vasculogenesis, and macrophage polarization. Calcium phosphate nanocrystals are grown on the surface of aligned, functionalized nanofiber microsheets. The microsheets are seeded with hMSCs, ECFCs, or a mixture of hMSCs + ECFCs, cultured for cell attachment, differentiated to the osteogenic or vasculogenic lineage, and devitalized by lyophilization. The release kinetic of total protein, bone morphogenetic protein‐2 (BMP2), and vascular endothelial growth factor (VEGF) from the devitalized microsheets is measured. Next, hMSCs and/or ECFCs are seeded on the devitalized cell microsheets and cultured in the absence of osteo‐/vasculoinductive factors to determine the effect of devitalized cell microsheets on hMSC/ECFC differentiation. Human macrophages are seeded on the microsheets to determine the effect of devitalized cells on macrophage polarization. Based on the results, devitalized undifferentiated hMSC and vasculogenic‐differentiated ECFC microsheets have highest sustained release of BMP2 and VEGF, respectively. The devitalized hMSC microsheets do not affect M2 macrophage polarization while vascular‐differentiated, devitalized ECFC microsheets do not affect M1 polarization. Both groups stimulate higher M2 macrophage polarization compared to M1.

 
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PAR ID:
10034625
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Biosystems
Volume:
1
Issue:
3
ISSN:
2366-7478
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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