Analysis of biological roles of class II major histocompatibility antigen by anti-sense RNA

我们已经建立了一个反义RNA系统，它能够调节内源性II类MHC(La)分子的表达，从而消除la分子在免疫反应中的作用。在金属硫蛋白基因启动子的控制下，反义构建了L-A链基因的100个碱基对。将该反义基因导入La^+B淋巴瘤细胞。转染体上La分子的数量被特异性地降低到对照水平的5%以下。转染体中反义和正义mRNA的比例与La分子的数量相关，表明正义和反义RNA的双重形成抑制了正义mRNA的翻译。同时，将该反义基因显微注射到C57BL/6xSJL F1小鼠受精卵中饲养转基因小鼠。在这些转基因小鼠中，1)脾细胞上的La分子数量明显减少，2)在转基因小鼠的脾细胞总RNA中检测到反义RNA。我们正在检查这些小鼠的免疫异常。

We have established an anti-sense RNA system which is capable of regulating the expression of the endogenous class II MHC (la) molecule in order to elusidate the role of la molecules on immune responses. The 100 base pairs of the l-A chain gene were constructed under the control of a metallothionein gene promoter in an anti-sense orientation. This anti-sense gene was taransfected into the la^+ B lymphoma cells. The amount of la molecules on the transfectants was specifically reduced to less than 5% of the control level. The rations of the amount of anti-sense and sense mRNA in the transfectants correlated with the amount of the la molecules, indicating that the duplex fomation of sense and anti-sense RNA inhibits translation of the sense mRNA. Antigen presenting cell activities of the transfectants to the la restricted T cells also correlated with the amount of la molecules.simultaneously, this anti-sense gene was microinjected into fertilized eggs of C57BL/6xSJL F1 mice to raise the transgenic mice. In these transgenic mice, 1)the amount of la molecules on the spleen cells was distinctly reduced, 2) anti-sense rna was detected in total RNA from spleen cells of the transgenic mice. We are examining immune abnormalities of these mice.