Analysis of T cell receptor repertoire in primary biliary cirrhosis

T细胞在原发性胆汁性肝硬化（PBC）胆管破坏中起重要作用。为了分析负责这种胆管破坏的T细胞，在肝活检标本中研究了T细胞受体（TCR）V β库，并且还在从9名早期PBC患者（Scheuer I期或II期）获得的外周血淋巴细胞（PBL）中研究。用<1-20>逆转录-聚合酶链反应（RT-PCR）扩增T细胞受体V β链cDNA，并对PCR产物进行单链构象多态性（SSCP）分析。在RT-PCR/SSCP分析中，白血病细胞系HPB-ALL显示TCRV β 5.2和V β 6条带，表明具有不同TCR的克隆扩增。在健康受试者的PBL中，大多数TCRV β PCR产物扩增，并在SSCP上显示为涂片，表明PBL由不同的T细胞克隆组成。在PBC中，大多数TCR V β产物也通过RT-PCR在肝组织和PBL中扩增，并且没有观察到特定V β的偏倚表达。SSCP分析揭示了大多数V β链中的多个条带，表明存在选择的但多个T细胞克隆。PBC患者中显示克隆扩增的V β的数量和类型都是异质性的，尽管在V β 6中鉴定出克隆数量增加。提示PBC患者肝脏浸润的T细胞由多种克隆型组成，TCR V β 6型T细胞可能在PBC的发病机制中起一定作用。

T cells play an important role in the destruction of bile duct in primary biliary cirrhosis (PBC). To analyze the T cells responsible for this bile ductt destruction, the T cell receptor (TCR) V beta repertoire was studied in liver biopsy specimens, and also in peripheral blood lymphocytes (PBL) obtained from 9 patients with PBC in the early stage (Scheuer's Stage I or II). The cDNA of each TCR V beta _<1-20> chain was prepared and amplified by reverse transcription-polymerase chain reaction (RT-PCR) and the PCR products were examined by single strand conformation polymorphism (SSCP) analysis. On the RT-PCR/SSCP analysis, a leukemic cell line, HPB-ALL,showed bands in TCR V beta 5.2 and V beta 6, indicating clonal expansion with distinct TCR.In PBL from healthy subjects, PCR products were amplified in most TCRV beta and were demonstrated as smears on SSCP,suggesting that PBL consists of diverse T cell clones. In PBC,most TCR V beta products were also amplified by RT-PCR in both liver tissues and PBL,and no biased expression of a particular V beta was observed. SSCP analysis revealed multiple bands in most V beta chains, suggesting the presence of selected but multiple T cell clones. Both the number and types of V beta showing clonal expansion were heterogeneous in PBC patients, although an increased number of clones was identified in V beta 6. These results suggest that T cells infiltrating the liver in PBC consist of multiple clonotypes and that T cells with TCR V beta 6 may play some role in the pathogenesis of PBC.