转染不同基因的NIT细胞体外抗细胞毒T细胞杀伤作用

Resistance against the killing of the cytotoxic T lymphocytes in NIT cells after transfected different genes in vitro

目的研究转染FADD缺失突变体（FADDdel）和WeelHu／GFP的胰岛β细胞株（NIT细胞）抵抗细胞毒T细胞的杀伤作用及其分泌胰岛素与细胞增殖所受的影响。方法采用免疫磁珠法测量转染WeelHu基因的NIT细胞培养上清中的胰岛素水平及观察其增殖速度。将分别转染空载体pUC-pIC、pCMV和转染pFADDdel、pCMV-WeelHu、pCMV-WeelHu／GFP的NIT细胞与活化的淋巴细胞共培养，利用^51Cr释放试验检测淋巴细胞对NIT细胞的杀伤作用。结果转染weelHu基因与未转染的NIT细胞胰岛素的分泌和生长速度没有明显变化（P〉0．05）。转染pCMV-WeelHu／GFP或pCMV-WeelHu的NIT细胞其抗淋巴细胞杀伤能力明显高于转染空载体的NIT细胞（P〈0．01），表达weelHu或WeelHu／GFP融合蛋白的胰岛细胞之间抗凋亡能力差异无统计学意义，转染FADDdel在低剂量效靶比时对胰岛β细胞有一定保护作用（P〈0．05），但在高剂量效靶比时与转染空载体比较差异无统计学意义（P〉0．05）。结论表达WeelHu或FADDdel的胰岛细胞可抵抗T细胞的杀伤，且对胰岛素的分泌及细胞增殖无明显影响。

Objective To study the effects of islet β-cell line （NIT cells） transfected with pFADDdel, WeelHu or WeelHu/GFP on insulin secretion, growth rate and resistance against the killing cytotoxic T lymphocytes （ETL）. Methods The level of insulin in culture supernatant of NIT cells was measured by immune magnetic bead method and their growth rate was observed. Active lymphocytes were cultured with the NIT cells transfected with pUG-piE, pCMV, pFADDdel, pGMV-WeelHu, pGMV-WeelHu/GFP. The killing effects of the T cells were tested by ^51 Gr release method. Results The insulin level and growth rate of NIT cells transfected with WeelHu gene or without transfection were observed at the same time, and no significant differences between beth groups were found （P 〉0. 05 ）. NIT cells transfected with pGMV-WeelHu or pGMV-WeelHu/GFP had stronger ability to resist the killing of lymphocytes than NIT cells transfected with empty vector （ P 〈 0.01 ）. NIT cells transfected with pFADDdel protected themsclf at low effect target ratio, however, the protective effects had no differences at high effect target ratio compared with NIT transfected with empty vector （ P 〉 0. 05 ）. Conclusion There were no obvious effect on insulin secretion and growth rate of NIT cells after transfected with WeelHu gene. NIT cells transfected with WeelHu,WeelHu/GFP or FADDdel can resist the killing effects of T cells.