[Effects of H2-Bl gene transfection on biological behaviour of mouse vascular smooth muscle cell]

To investigate the effects of H2-Bl gene on biological behaviour of mouse vascular smooth muscle cells (VSMCs) including apoptosis, proliferation and anti-cytolysis to peripheral blood mononuclear cells (PBMCs), then speculate the possible mechanism of immunological rejection after heart transplantation in maternal-fetal immune tolerance.

The mouse VSMC were transfected with 0.5 mg/L of pEGFP-N1 plasmid vector, 0.5 mg/L of pEGFP-N1-H2B1 plasmid vector and 1.0 mg/L of pEGFP-N1-H2B1 plasmid vector, respectively. The efficiency of transfection was detected, and the H2-Bl mRNA level, the apoptosis, the proliferation and cytotoxicity of VSMCs were also investigated at 24 h, 48 h and 72 h, respectively.

Expression of the H2-Bl gene was determined by real time quantitative PCR. Expressions of the H2-Bl in experimental groups were higher than that of the control group (P<0.001). VSMC apoptosis was observed after 24 h in the 0.5 mg/L and 1.0 mg/L H2-Bl experimental groups compared with control group (P<0.05, P<0.001, respectively). VSMC proliferation was also inhibited in the 0.5 mg/L and 1.0 mg/L H2-Bl gene groups at 24 h and 72 h (P<0.05, P<0.01, respectively). The cytotoxicity of PBMC in the 0.5 mg/L and 1.0 mg/L H2-Bl gene groups at 24 h was lower than the control group (P<0.005, P<0.001, respectively).

Transfection of pEGFP-N1-H2B1 plasmid to mouse VSMC causes the over expression of H2-Bl mRNA, induces the apoptosis, inhibits the proliferation and attenuates the cytotoxicity of PBMC, leading to immune tolerance.