SPD-01

Objective To investigate the effects of lentivirus-mediated overexpression of interferon gamma (IFN-γ) and soluble programmed death 1 (sPD-1) on the biological activity and genetic stability of bone marrow mesenchymal stem cells (BMSCs). Methods BMSCs were isolated and cultured by whole bone marrow adhesion method. The expression of surface markers of BMSCs was identified by flow cytometry. IFN-γ and sPD-1 gene sequences with green fluorescent protein (GFP) and red fluorescent protein (RFP) were amplified, and BMSCs overexpressing IFN-γ, sPD-1, and IFN-γ/sPD-1 were constructed by lentiviral transfection. The cell morphology was observed using an inverted microscope. The mRNA and protein expression of IFN-γ and sPD-1 were detected by real-time fluorescence quantitative PCR and Western blot analysis, respectively. The biological activity of the IFN-γ and sPD-1 overexpression BMSCs was assessed through functional assays, while their genetic stability was analysed using karyotyping. Results BMSCs positive for CD44 and CD105 and negative for CD34, CD11b and CD45 were successfully isolated and cultured. Compared with the empty group, IFN-γ and sPD-1 mRNA expression levels were significantly higher in the combined IFN-γ/sPD-1 group, but the growth of cells was similar in all groups; the telomerase activity was significantly reduced in the IFN-γ group, but the changes in telomerase activity were not obvious in the sPD-1 group and the combined IFN-γ/sPD-1 group. Conclusion BMSCs overexpressing IFN-γ and sPD-1 in combination has high biological activity and genetic stability.