Abstract:

BACKGROUND: Fibrin is a kind of high polymer materials with biodegradation and good histocompatibility. Fibrin stabilizing factor ⅩⅢ has been verified that it can contribute to the migration of undifferentiated mesenchymal stem cells (MSCs) in gel scaffold with high crosslinking, and promote its proliferation and differentiation.
OBJECTIVE: To analyze morphological changes of rat embryonic MSCs in fibrin gel of different mass concentrations, and to observe the growth, proliferation and osteogenic differentiation.
METHODS: To isolate and culture fetal limbs mesenehymal stem cells (flMSCs) under aseptic condition using tissue digesting method. The third passage of flMSCs were incubated in three different concentrations (20, 10 and 5 g/L) of fibrin gels. A control group was set and incubated in normal medium without gel. The cell morphology in fibrin gels was observed by confocal laser scanning microscope. Cell proliferation was assessed by fluorospectrophotometer. A microplate reader and Von Kossa staining were used to analyze alkaline phosphatase (ALP) activity and calcium salts mineralization.
RESULTS AND CONCLUSION: FlMSCs had long processes which connected each other and formed network in fibrin gels, but fusiform or cube cells were observed in the control group at 7 days. Compared with the control group, cell proliferation was great in the fibrin gel group, and peaked at day 14, especially in the 5 g/L fibrin gel group. ALP activity was increased at day 14 in the fibrin gel group, and reached a peak at day 21. Following 14 days of incubation, mineralization was observed in 20 g/L fibrin gel group, and then gradually fused. However, no mineralization was detected in the control group. Results verified that fibrin gel scaffold can support the survival and growth of rat embryonic MSCs, and promote cell proliferation and differentiation. 5 g/L fibrin gel contributes to cell morphological changes, and 20 g/L fibrin gel contributes to osteogenic differentiation.