TCR V GENE REPERTOIRE IN MS AND SELECTIVE IMMUNOTHERAPY

我们在MS脑中发现了VDJβ和VJα基因重排 编码与T细胞中相同的氨基酸序列的斑块 具有髓鞘特异性的人、小鼠和大鼠细胞克隆 碱性蛋白(MBP)肽87-99。使用高效表达式 系统，我们将严格证明a 多发性硬化病变中的主要T细胞反应针对MBPp87-99。我们有 开发出有效的p87-99 T细胞受体拮抗剂 在EAE啮齿动物模型中持续瘫痪，并抑制增殖和 人类对p87-99的细胞毒反应。我们将确定推定的 TCR CDR3区氨基酸与p87-99残基的接触。 在该表位中发现了一个含有MBP87-91(VHFFK)的核心基序。一个 许多微生物与该核心基序VHFFK具有序列同源性， 刺激MBPp87-99特异性T细胞。我们将确定是否 微生物表位可以同样有效地触发转基因构建体 作为天然的MBP表位。这将表明这些T细胞如何 在感染过程中被激活，支持自我- 反应性源于自身抗原的分子模拟，通过 微生物。由于对MBP p87-99有反应的T细胞会触发EAE，我们将测试 这些微生物序列是否会引发EAE，或者 无论它们是作为TCR或MHC拮抗剂，还是可以阻止疾病 归纳法。因此，我们将考虑MBP表位的分子模拟 可以诱发疾病或保护免受病理影响。 我们已经证明了在多发性硬化症中发现的显性抗体反应 脑斑块和多发性硬化症的脑脊液是有重叠的 P86-99的MBP分子区域。这个表位与 表位受HLADR2β(HLADRB1*1501)限制，并与 HLADR2α限制表位(HLADRB5*0101)。我们将分析 免疫球蛋白基因重排在多发性硬化症脑内和脑脊液中的应用 采用单细胞聚合酶链式反应。我们会看看是否有限制性的Ig CDR3 MS中的基序我们将把这些CDR3基序与在小鼠中发现的基序进行比较 针对相同表位p86-99产生的单抗。我们的 始终如一的目标是开发针对多发性硬化症的选择性免疫疗法 硬化症，一种影响中枢神经系统的慢性疾病 大约25万美国人。

We have discovered VDJ beta and VJ alpha gene rearrangements in MS brain plaques that encode amino acid sequences identical to those seen in T cell clones from humans, mice and rats that have specificity for myelin basic protein (MBP) peptide 87-99. Using a high-efficiency expression system for TCR alpha and beta chains, we will rigorously prove that a major T cell response in the MS lesion is directed to MBPp87-99. We have developed potent T cell receptor antagonists for p87-99 that suppress ongoing paralysis in rodent models of EAE, and suppress proliferative and cytotoxic responses to p87-99 in humans. We will determine the putative contacts for amino acids in the TCR CDR3 regions with residues of p87-99. A core motif containing MBP87-91 (VHFFK) is found in this epitope. A number of microbes share sequence homology with this core motif-VHFFK, and stimulate MBPp87-99 specific T cells. We will determine whether microbial epitopes can trigger the transfected construct, as efficiently as the native MBP epitope. This would indicate how these T cells might become activated during infection, supporting the notion that self- reactivity arises from the molecular mimicry of self-antigens by microbes. Since T cells reactive to MBP p87-99 trigger EAE, we will test whether these microbial sequences either trigger EAE, or alternatively whether they serve as TCR or MHC antagonists and can block disease induction. Thus we will consider whether molecular mimics of MBP epitopes can induce disease or protect from pathology. We have demonstrated that a dominant antibody response found in the MS brain plaque and in MS cerebrospinal fluid is directed to an overlapping region of the MBP molecule from p86-99. This epitope is identical to the epitope restricted by HLA DR2 beta (HLA DRB1*1501), and overlaps with the epitope restricted by HLA DR2 alpha (HLA DRB5*0101). We will analyze immunoglobulin gene rearrangements in MS brain using RT-PCR, and in CSF using single cell PCR. We will see whether there are restricted Ig CDR3 motifs in MS. We will compare these CDR3 motifs to those found in murine monoclonal antibodies raised against the identical epitope p86-99. Our persistent goal is to develop selective immunotherapy for multiple sclerosis, a chronic disease of the central nervous system affecting approximately 250,000 Americans.