The Effects Of Short-term Cryopreservation On The Proliferation, Bio-characteristics And Osteogenic Potentiality Of Rabbit BMSCs

Objective: To study the impacts of short-term cryopreservation on theproliferation, bio-characteristics and osteogenic capability of rabbit BMSCs, andlay the foundation for the further study. Methods: The5th generation of rabbitBMSCs were cryopreservated by liquid nitrogen for30days, and then thawingthe cells to culture it to the10th generation in vitro, put the non-cryopreservatedand the same generation BMSCs as the control group. The MTT, cell cycle, cellsurface marker, the content of ALP and the immunohistochemical staining forcollagen typeⅠ and alizarin red staining for calcium after differentiationinduced by osteogenesis were used to evaluate the proliferation,bio-characteristic and osteogenic differentiation capability of rabbit BMSCs.Results: The survival rate of rabbit BMSCs after cryopreservated is84.38%±3.78%. The growth incubation period of BMSCs was extended, but itgradually recover through serial passage. The proliferation index (PI) and theproportion of BMSCs in G1phase are42.9%±3.4%and57.0%±3.4%respectively. The positive rate of cell surface marker of CD44is93.62%±1.05%,without expression of CD45. The contents of ALP(U/gprot) are6.73±1.92and15.99±4.36in BMSCs after7th day and14th day with osteogenic induction, respectively. The collagen typeⅠ and alizarin red staining for calcium indicatedpositive at BMSCs after14th day and21th day with osteogenic induction,respectively. Compared to the control group, Runx2gene and OC geneexpression were not changed obviously at BMSCs after7th day and14th daywith osteogenic induction, respectively. These results showed no significantdifference compared with the control group (P>0.05). Conclusions: Short-termcryopreservation has no obvious impacts on the proliferation, bio-characteristicand osteogenic capability of BMSCs and it could be used for further study.