Simpson I J, Skinner M A, Geursen A, Peake J S, Abbott W G, Fraser J D, Lockwood C M, Tan P L
Department of Medicine, University of Auckland, New Zealand.
Clin Exp Immunol. 1995 Aug;101(2):220-6. doi: 10.1111/j.1365-2249.1995.tb08342.x.
Antigen recognition by T lymphocytes is mediated by cell surface receptors T cell specificity depends on the variable, diversity and junctional (VDJ) regions of the alpha and beta polypeptide chains of the T cell receptor (TCR). The expression of the variable region genes of the beta chain (V beta) has been analysed to study the involvement of peripheral blood T cells in systemic vasculitis. RNA was extracted from peripheral blood lymphocytes of 12 patients with microscopic polyarteritis, 10 with Wegener's granulomatosis, six with unclassified vasculitis, and 28 healthy age- and sex-matched individuals. Complementary DNA was made from RNA and amplified by the anchored polymerase chain reaction (PCR) using redundant oligonucleotide primers for the TCR V beta genes. To determine if the dominant usage of a V beta gene family reflected the presence of particular T cell clones, cDNA was amplified with primers for the specific V beta gene family. The product was screened for sequence homogeneity by single-stranded conformational polymorphism (SSCP) and cloned to sequence the adjoining TCR (D beta) J beta region. A significant increase in the mean percentage expression of the V beta 2.1 gene was seen in vasculitis patients (11.4 + 1.0% (mean + s.e.m.)) compared with controls (6.6 + 0.6%; P < 0.003). The most marked increase was seen in microscopic polyarteritis (13.9 + 1.7%; P < 0.0001). There were also increases in the expression of V beta 3, 13 and 14 in peripheral blood of vasculitis patients compared with controls. SSCP analysis of V beta 2.1 amplified products indicated the presence of oligoclonal bands in a smaller proportion of patients (8/27) than controls (12/28). There was no strong evidence for the conservation of the TCR V beta 2.1 junctional region sequence data from a sample group of three patients with oligoclonal bands. Thus, a subset of patients with systemic vasculitis, particularly those with microscopic polyarteritis, have increased TCR V beta 2.1 gene expression in their peripheral blood T cell repertoire. As superantigens binding V beta 2.1 are postulated to activate T cells with diverse CDR3 sequences, it is proposed that a superantigen is involved in the immunopathogenesis of vasculitis.
T淋巴细胞对抗原的识别由细胞表面受体介导。T细胞的特异性取决于T细胞受体（TCR）α和β多肽链的可变区、多样区和连接区（VDJ）。为研究外周血T细胞在系统性血管炎中的作用，分析了β链可变区基因（Vβ）的表达。从12例显微镜下多动脉炎患者、10例韦格纳肉芽肿患者、6例未分类血管炎患者以及28例年龄和性别匹配的健康个体的外周血淋巴细胞中提取RNA。以RNA为模板合成互补DNA，并使用针对TCR Vβ基因的冗余寡核苷酸引物通过锚定聚合酶链反应（PCR）进行扩增。为确定Vβ基因家族的优势使用是否反映特定T细胞克隆的存在，用针对特定Vβ基因家族的引物扩增cDNA。通过单链构象多态性（SSCP）筛选产物的序列同质性，并克隆以对相邻的TCR（Dβ）Jβ区域进行测序。与对照组（6.6 + 0.6%）相比，血管炎患者中Vβ2.1基因的平均表达百分比显著增加（11.4 + 1.0%（平均值 + 标准误）；P < 0.003）。在显微镜下多动脉炎中增加最为明显（13.9 + 1.7%；P < 0.0001）。与对照组相比，血管炎患者外周血中Vβ3、13和14的表达也有所增加。对Vβ2.1扩增产物的SSCP分析表明，出现寡克隆条带的患者比例（8/27）低于对照组（12/28）。对于来自3例有寡克隆条带患者的样本组，没有强有力的证据表明TCR Vβ2.1连接区序列数据具有保守性。因此，系统性血管炎患者的一个亚组，特别是显微镜下多动脉炎患者，其外周血T细胞库中TCR Vβ2.1基因表达增加。由于推测结合Vβ2.1的超抗原有激活具有不同CDR3序列的T细胞的作用，因此提出超抗原参与了血管炎的免疫发病机制。
