RESUMO
The present study was aimed to explore the possible mechanisms by which caprine Wharton's jelly-derived MSCs (WJ-MSCs) perform their immunomodulatory function. WJ-MSCs were isolated through explants culture and characterized as per ISCT criteria using culture behavior, expression of surface markers by PCR, FACS and immunocytochemical localization (ICC), trilineage differentiation potential etc. Secretory behavior for important biomolecules (IDO, TGFß1, VEGF, IL6) was evaluated by ICC and western blot assay. Cell-to-cell communication was studied by culturing cells in cell-cell contact and trans-well system. The MSCs when co-cultured with activated Tc and Th cells, down-regulation of T cell cytokine as well as upregulation of immunomodulatory factors (VEGF A, IL10, IL6, IDO, iNOS, PTGS2, HGF, TGFß, CXCL10, CXCL11) was noticed in both cell-cell contact and trans-well culture system which was significantly higher in cell-cell contact system. Trilineage differentiation of MSCs showed significant upregulation of MHC I (CAHI) and MHC II (CLA DRB3) molecules suggesting better clinical applications of MSCs without differentiation to avoid immune rejection. It can be concluded that WJ-MSCs perform their immunomodulation through the secretion of a battery of biomolecules and work in both cell-cell contact manner and through their secretome.
RESUMO
Mesenchymal stem cells-conditioned media (MSCs-CM) contains several growth factors and cytokines, thus may be used as a better alternative to stem cell therapy, which needs to be elucidated. The present study was conducted to evaluate the therapeutic potential of caprine, canine, and guinea pig bone marrow-derived MSCs-CM in excision wound healing in a guinea pig model. MSCs were obtained from bone marrow, expanded ex vivo and characterized as per ISCT criteria. CM was collected assayed by western blot to ascertain the presence of important secretory biomolecules. Quantitative estimation by enzyme-linked immunosorbent assay was done for a vascular epidermal growth factor (VEGF) and interleukin-6 (IL-6) in caprine MSCs-CM and optimum time for collection of CM was decided as 72 hr. CM from all the species was lyophilized by freeze-drying method. Full-thickness (2 × 2 cm2 ) excision skin wounds were created in guinea pigs (six animals in each group) and respective lyophilized CM mixed with laminin gel was applied topically at weekly interval. On Day 28, histopathological examinations of healed skin were done by hemotoxylin and eosin staining. MSCs were found to secrete important growth factors and cytokines (i.e., VEGF, transforming growth factor-ß1, fibroblast growth factor-2, insulin-like growth factor-1, stem cell factor, and IL-6) as demonstrated by immunohistochemistry and western blot assay. It was found that allogenic and xenogenic application of CM significantly improved quality wound healing with minimal scar formation. Thus, MSCs-CM can be used allogenically as well as xenogenically for quality wound healing.