Abstract:

Objective To investigate the effect of CD73 on the proliferation and senescence of bone marrow mesenchymal stem cells (BMSCs). Methods The mouse BMSCs were cultured in vitro. We constructed lentivirus of CD73 overexpression and CD73 RNAi vectors and transfected into the BMSCs. The experimental groups were divided into three groups: CD73 overexpression group (OE group), CD73 RNAi interference group (RNAi group) and control group (CON group). Galactosidase (SA-β-Gal) staining was used to detect the cell senescence. Cell proliferation was measured by MTT assay. Cell cycle was detected by flow cytometry. Ultrastructures were observed by transmission electron microscopy (TEM). The cell growth curve was detected by non-injured cell function analyzer. Results The number of senescent cells in RNAi group was significantly higher than that in CON and OE groups (P<0.05) at 72 hours post-transfection. The proliferation of BMSCs in OE group was significantly higher than CON and RNAi groups at 72 and 96 hours post-transfection (P<0.05). The percentages of G₁ phase cells in OE group, RNAi group and CON group were 25.9%, 44.1% and 51.7%, respectively, and that of S phase cells were 48.8%, 30.9% and 26.9%, respectively. The percentage of cells in G₂ phase were 25.2%, 25.0% and 21.4%, respectively. The result of transmission electron microscopy showed that the cell rough endoplasmic reticulum and the ribosomes were increased in the OE group. The cell growth curve showed that the cell proliferation ability in OE group was higher than that in CON group and RNAi group. Conclusion CD73 promotes BMSCs proliferation and inhibits BMSC senescence.

Key words: CD73, Proliferation, Senescence, Bone marrow mesenchymal stem cell, Ultrastructure, Flow cytometry, Mouse