Pathomechanisms of paraneoplastic neurological syndrome-neuronal damege mediated by cytotoxic T cells

副肿瘤性神经综合征-细胞毒性T细胞介导的神经元损伤的发病机制

基本信息

批准号：
11670614
负责人：
TANAKA Keiko
金额：
$ 1.92万
依托单位：
NIIGATA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

项目摘要

A part of the paraneoplastic neurological syndrome could be diagnosed with characteristic anti-neuronal antibodies which also give the prediction for underlying cancer. Although these antibodies found in the sera and CSFs of patients is thought to be disease- specific, there is no direct evidence of a role in neuronal loss. Infiltration of CD8-positive T cells in the affected tissue was found in the patient with paraneoplastic cerebellar degeneration(PCD)and anti-Yo antibody or encepahlomyeloneuropathy with anti-Hu antibody(anti-Hu syndrome)which suggested HLA class I restricted cytotoxic T cells(CTL)may be involved in these disorders. First, we examined Vb genes of T cell receptors of infiltrated lymphocytes with RT-PCR and single strand conformational polym orphism method, that suggested the oligoclonal expansions of T cells in the tumor and the cerebellum/posterior ganglions of PCD/anti-Hu syndrome, respectively.Then we examined HLA-class I- restricted cytotoxic T lymphocyte(CTL)activity against a peptid of the Yoprotein with the HLA A24-specific peptide-binding motifs or some peptides of the Hu protein with the B7 supertype-specific peptide binding motifs. CTL activity was induced in the peripheral blood of patients with PCD/anti-Hu syndrome after stimulated with specific peptides against autologous fibroblasts expressing each peptide on their surface. To clarify that CTL might really related to the neuronal damage, CTL induced animal models should be raised.For this purpose, we immunized the mice bering common MHC motifs with these peptides and autologous dendritic cells and obtained T cell clones reactive to each peptides.

部分副肿瘤性神经综合征可以通过特征性抗神经元抗体进行诊断，这些抗体也可以预测潜在的癌症。尽管在患者血清和脑脊液中发现的这些抗体被认为是疾病特异性的，但没有直接证据表明其在神经元损失中起作用。在副肿瘤性小脑变性（PCD）和抗Yo抗体或抗Hu抗体（抗Hu综合征）脑脊髓神经病患者中发现受累组织中有CD8阳性T细胞浸润，提示HLA I类限制性细胞毒性T细胞(CTL) 可能与这些疾病有关。首先，我们用RT-PCR和单链构象多态性方法检测了浸润淋巴细胞的T细胞受体Vb基因，这表明PCD/抗Hu综合征的肿瘤和小脑/后神经节中T细胞的寡克隆扩增，然后我们检测了针对具有 HLA A24 特异性的 Yo 蛋白肽的 HLA-I 类限制性细胞毒性 T 淋巴细胞 (CTL) 活性。肽结合基序或具有 B7 超型特异性肽结合基序的 Hu 蛋白的一些肽。在用针对表面表达每种肽的自体成纤维细胞的特定肽刺激后，PCD/抗Hu综合征患者的外周血中诱导了CTL活性。为了阐明CTL可能确实与神经元损伤有关，应该建立CTL诱导的动物模型。为此，我们用这些肽和自体树突状细胞对具有常见MHC基序的小鼠进行免疫，并获得对每种肽有反应的T细胞克隆。