ENDOGENOUS RETROVIRUSES AS A CAUSAL MECHANISM IN LUPUS

内源性逆转录病毒（ERV）是人类的潜在病原体， 鼠自身免疫 一类ERV，Mpmv，在小鼠胸腺中转录， 5个狼疮倾向小鼠品系，但11个对照小鼠品系中没有。 在狼疮倾向 小鼠，胸腺Mpmv RNA表达从出生的第一天起就异常， 这表明它可能与易患 自身免疫 为了确定Mpmv编码的蛋白质是否直接 有助于自身免疫，它们的表达将在转基因中被阻断， 狼疮鼠 我们的初步数据和发表的报告，从四个 针对其他基因（包括逆转录病毒）的不同群体表明， 反义RNA在Mpmv基因表达调控中的应用 转基因小鼠 使用高度表达Mpmv RNA的T细胞系， 蛋白质，我们将测试多种表达反义RNA的构建体， 不同的启动子和增强子下的不同Mpmv序列。 首先，我们将关注以前使用的基于CMV的向量 成功地在转基因小鼠中保护免受感染性逆转录病毒 通过表达反义RNA。 确定的最有希望的载体 稳定转染入T细胞系将用于产生 转基因狼疮易感小鼠，然后将进行研究，以确定是否 疾病表型已经改变。 以前使用重组近交和回交小鼠的遗传研究， 证明了几种自身免疫性状独立分离。 到 确定胸腺Mpmv RNA表达是否可能与 自身免疫的特殊特征，我们将进行北方分析， 在狼疮倾向的NZB和 对照SM/J小鼠。 最后，本申请将继续我们的初步研究， 表明Mpmv转录是由基因失调引起 在狼疮中的表达。 导致Mpmv异常的DNA序列 将鉴定和表征狼疮易感小鼠中的转录。 由于对狼疮的异常基因调控还不清楚， Mpmv表达的调节可能会导致对 人类和鼠类狼疮的分子遗传缺陷。

Endogenous retroviruses (ERV) are potential etiologic agents in human and murine autoimmunity. A class of ERV, Mpmv, is transcribed in thymuses of 5 lupus-prone but in none of 11 control mouse strains. In lupus-prone mice, thymus Mpmv RNA expression is abnormal from day one of life, suggesting that it may be closely linked to genes which predispose to autoimmunity. To determine whether the proteins encoded by Mpmv directly contribute to autoimmunity, their expression will be blocked in transgenic lupus mice. Our preliminary data and published reports from four different groups targeting other genes (including a retrovirus) indicate the potential utility of antisense RNA for manipulating Mpmv expression in transgenic mice. Using a T cell line that highly expresses Mpmv RNA and protein, we will test multiple constructs expressing antisense RNA to different Mpmv sequences under different promoters and enhancers. Initially, we will focus on the CMV-based vector previously used successfully in transgenic mice to protect against infectious retrovirus by expressing antisense RNA. The most promising vectors identified by stable transfection into the T cell line will be used to generate transgenic lupus-prone mice, which will then be studied to determine if the disease phenotype has been altered. Previous genetic studies using recombinant inbred and backcross mice have demonstrated that several autoimmune traits segregate independently. To determine whether thymus Mpmv RNA expression may cosegregate with a particular feature of autoimmunity, we will perform Northern analyses of well-characterized recombinant inbred lines between lupus-prone NZB and control SM/J mice. Finally, the present application will pursue our preliminary studies which indicate that Mpmv transcription results from a dysregulation of gene expression in lupus. The DNA sequences responsible for abnormal Mpmv transcription in lupus-prone mice will be identified and characterized. Since abnormal gene regulation in lupus is not well understood, studies of the regulation of Mpmv expression could lead to new insights into the molecular genetic defects of human and murine lupus.