HLA-G诱导T细胞免疫耐受的实验研究

Experimental Study on the T Cell Immunotolerance Induced by HLA-G Molecule

用W6/ 3 2单抗对JEG 3细胞进行免疫荧光染色 ,可见在JEG 3细胞膜表面有高强度的黄绿色荧光。HLA G+的JEG 3细胞作为刺激细胞 ,观察其对淋巴细胞增殖反应的影响 ,结果JEG 3细胞不能刺激淋巴细胞增殖。采用经典的单向混合淋巴细胞培养的方法 ,以转染及未转染HLA G分子的K5 62细胞作为抑制细胞 ,按一定的比例加入反应体系 ,结果表明 ,转染HLA G的K5 62细胞能抑制淋巴细胞的增殖反应 ,该抑制以刺激细胞∶反应细胞∶抑制细胞的比例为 1∶1∶2时效果最明显 ,抑制率为 5 4 1% (P <0 0 1) ,转染空质粒和未转染HLA G的K5 62细胞均无明显抑制作用。外周血淋巴细胞与JEG 3细胞共同孵育 ,碘化丙啶 (PI)染色 ,流式细胞仪观察 ,结果发现 ,HLA G分子能诱导淋巴细胞的凋亡。

To investigate the ability of HLA G molecule to modulate the allo proliferative response of T cells,JEG 3 cells were stained by indirect immunofluorescence with W6/32 mAb which showed strong yellow green colored fluorescence on JEG 3 cells The HLA G + JEG 3 cells,when used as the stimulating cells,did not induce the proliferative response of lymphocytes,but when they were used as an inhibitory cells in the classical one way mixed lymphocyte reaction(MLR),it was found that the K562 cells transfected with the HLA G gene could inhibit the proliferative response of lymphocytes in vitro This inhibitory effect was rather prominent at the stimulator∶resonder∶inhibitor∶proportions of 1∶1∶2 and the percentage of inhibition was 54 1%( P <0 01) K562 cells transfected with the vector plasmid or the un transfected K562 cells both showed no inhibitory effect In addition apoptosis was found by FACS analysis according to the percentage of cells with the propidium iodide(PI) staining indication that the HLA G molecule may also induce cell apoptosis and regulate the T cell proliferation