重组人CTLA4-Ig对T细胞活化功能的影响

EFFECTS OF HUMAN RECOMBINANT CTLA4-IG ON LYMPHOCYTE ACTIVATION

目的：分析真核表达产物ＣＴＬＡ４－ Ｉｇ 对Ｔ细胞活化功能的影响。方法：构建并用真核表达系统表达ＣＴＬＡ４ －Ｉｇ，通过蛋白Ａ亲合柱纯化获得纯品；然后观察ＣＴＬＡ４－Ｉｇ 对淋巴细胞转化功能及Ｔ细胞表面分子ＣＤ２５ 表达的影响；用３Ｈ－ ＴｄＲ掺入法研究ＣＴＬＡ４－Ｉｇ 对混合淋巴细胞反应的影响。结果：ＣＴＬＡ４－Ｉｇ 抑制ＰＨＡ对淋巴细胞的转化；同时，抑制ＰＨＡ刺激的淋巴细胞表面ＣＤ２５ 分子的表达，抑制率达５３ ％ ，与对照相比抑制显著（ Ｐ＜０．０５），且这种效应有剂量依赖性；ＣＴＬＡ４－Ｉｇ 抑制单向混合淋巴细胞反应，抑制率达８７．５３％ ，与对照相比亦抑制显著（ Ｐ＜０ ．０５） ，且效应亦呈剂量依赖性。结论：ＣＴＬＡ４－Ｉｇ 能有效阻断Ｔ细胞的活化，并且阻断效应是通过多种信号途径起作用的。

AIM To study the effects of the recombinant CTLA4-Ig on lymphocyte activation.METHODS The recombinant protein of CTLA4 and Fc were expressed in eukaryotic system and purified by protein A;PBL were isolated and stimulated by PHA or the other PBL and CTLA4-Ig or human IgG, to obtain the data of CTLA4-Ig on the lymphocyte transformation, the expression of CD25 on the T cell surface and MLC.RESULTS CTLA4-Ig blocked the lymphocyte transformation,and expression of CD25 on the T cell surface by 53%, whereas the control of human IgG did not. CTLA4-Ig inhibited the reaction of MLC by 87.53%, which were significantly higher than the control of human IgG (P<0.05).CONCLUSION The human recombinant CTLA4-Ig can block the lymphocyte activation through different pathway.