HGC12 INDUCTION OF SYSTEMIC AUTOIMMUNE DISEASE IN MICE

HGC12 诱导小鼠全身性自身免疫性疾病

基本信息

批准号：
2517401
负责人：
ERIC S SOBEL
金额：
$ 8.97万
依托单位：
UNIVERSITY OF FLORIDA
依托单位国家：
美国
项目类别：
财政年份：
1993
资助国家：
美国
起止时间：
1993-09-30 至 1999-08-31
项目状态：
已结题

项目摘要

The administration of low doses of HgCl2 three times weekly in susceptible strains of mice induces high titers of IgE, IgG1, and autoantibody to fibrillarin, a nuclear ribonucleoprotein involved in pre- ribosomal RNA processing. The anti-fibrillarin response has also been identified as a marker for human scleroderma. Through the use of intra- H-2 recombinants, it has been found that those mouse strains bearing the I-A(s) haplotype are high responders and that the high responder gene(s) is co-dominant. Moreover, this response appears to be reduced by the presence of I-E. The proposed experiments will define further the interactions necessary for a high-titer anti-fibrillarin response. The grant is divided into four Specific Aims. In Specific Aim 1, an allotype-specific ELISA for the detection of anti-fibrillarin will be developed. This assay will provide an important tool for measuring outcomes in Specific Aims 2 and 3. Specific Aim 2 will test critically whether the I-A(s) protein itself is necessary for the anti-fibrillarin response in HgCl2-treated mice. This will be performed by blocking A- A(s) specifically with high-affinity peptides in F1 crosses between susceptible B6.SJL (H-2(s)) and resistant C57BL/6 (H-2(b)) mice. If self-antigen must be presented in the context of I-A(s), then such blocking should decrease the anti-fibrillarin response to HgCl2. Alternatively, it may be that I-A-(s)-linked genes, such as those involved in antigen processing, are critical, and only by blocking both I-A(s) and I-A(b) can anti-fibrillarin production be decreased. In Specific Aim 3, it will be determined whether the anti-fibrillarin response in cognate and MHC-restricted using radiation chimeras. Furthermore, by examining offspring of F1 crosses between B6.SJL and the heterozygous I-E+ transgenic strain B6-Tg-I-Ea(d), it will be tested directly whether expression of I-E is the cause of down regulation. If so, additional chimera experiments will be performed to determine whether it is the expression of I-E itself on B cells that is the cause of down- regulation. Specific Aim 4 will determine whether any Vbeta genes are preferentially involved in the T-cell response to HgCl2. Successful completion of these experiments will focus further research on the possible mechanisms by which this environmental toxin can alter the immune system. This grant proposal is sponsored by Dr. Edward Wakeland, who has extensive experience working in murine genetics and the role of MHC in autoimmune disease. Drs. Robert Eisenberg and Philip Cohens will serve as collaborators on the project. The principal investigator, Dr. Sobel, has been trained in their laboratories. He has worked on in vivo studies of the cellular interactions leading to autoimmunity in the 1pr and gld murine models of SLE. This current proposal thus represents his first attempt at developing an independent project.

每周 3 次给予低剂量的 HgCl2 易感品系小鼠可诱导高滴度的 IgE、IgG1 和纤维蛋白自身抗体，纤维蛋白是一种核核糖核蛋白，参与预核糖体RNA加工。抗纤维蛋白反应也被证实被鉴定为人类硬皮病的标志物。通过使用内部 H-2 重组体，已发现那些带有 H-2 重组体的小鼠品系 I-A 单倍型是高反应者，并且高反应者基因是共同主导的。此外，这种反应似乎会因 I-E 的存在。拟议的实验将进一步定义高滴度抗纤维蛋白反应所必需的相互作用。这拨款分为四个具体目标。在具体目标 1 中，用于检测抗原纤维蛋白的同种异型特异性 ELISA 将发达。该测定将为测量提供重要的工具具体目标 2 和 3 中的结果。具体目标 2 将进行严格测试 I-A(s) 蛋白本身是否是抗纤维蛋白所必需的 HgCl2 处理小鼠的反应。这将通过阻止 A- 来执行 A(s) 与 F1 中的高亲和力肽特异性杂交易感 B6.SJL (H-2(s)) 和耐药 C57BL/6 (H-2(b)) 小鼠。如果自身抗原必须在 I-A(s) 的背景下呈现，然后这样阻断应降低 HgCl2 的抗纤维蛋白反应。或者，可能是 I-A-(s)-连锁基因，例如那些参与抗原加工，是至关重要的，并且只有通过阻断两者 I-A(s)和I-A(b)可以减少抗原纤维蛋白的产生。在具体目标3，将确定是否抗纤维蛋白使用辐射嵌合体进行同源和 MHC 限制的反应。此外，通过检查 B6.SJL 与 F1 杂交的后代杂合子I-E+转基因株B6-Tg-I-Ea(d)，将进行测试直接判断 I-E 的表达是否是下调的原因。如果因此，将进行额外的嵌合体实验以确定是否 I-E本身在B细胞上的表达是导致下调的原因规定。具体目标 4 将确定是否有任何 Vbeta 基因优先参与 T 细胞对 HgCl2 的反应。成功的这些实验的完成将集中于进一步的研究这种环境毒素改变的可能机制免疫系统。该拨款提案由爱德华·韦克兰博士赞助，他曾在小鼠遗传学和 MHC 的作用方面拥有丰富的经验自身免疫性疾病。博士。罗伯特·艾森伯格和菲利普·科恩斯将担任作为该项目的合作者。首席研究员 Sobel 博士，已在他们的实验室接受过培训。他从事体内研究导致 1pr 和 gld 自身免疫的细胞相互作用 SLE 小鼠模型。因此，当前的提案代表了他的第一个提案尝试开发一个独立的项目。