Mayo M J, Jenkins R N, Combes B, Lipsky P E
University of Texas Southwestern Medical Center at Dallas, Department of Internal Medicine, Dallas, TX, USA.
Hepatology. 1999 Jun;29(6):1635-42. doi: 10.1002/hep.510290637.
Clinical features of the CREST (calcinosis cutis, Raynaud's syndrome, esophageal dysmotility, sclerodactyly, and telangiectasias) syndrome are sometimes exhibited in patients with primary biliary cirrhosis (PBC), but the postulated autoimmune mechanisms behind these conditions are poorly understood. Clonally expanded T cells may play an important role in disease pathogenesis. In this study, overrepresentation of one T-cell receptor beta chain variable region, TCRBV3, was documented in patients with PBC and/or CREST. Overrepresentation of the TCRBV3 gene mRNA was demonstrated by semiquantitative reverse-transcriptase polymerase chain reaction (RT-PCR). T cells expressing TCRBV3 were analyzed by flow cytometry, were primarily CD8(+), and contained activated cells as assessed by expression of CD69. Clonally expanded T cells within this population were documented by both complementarity determining region 3 (CDR3) length polymorphism analysis and sequencing of T-cell receptor CDR3 cDNA. TCRBV3(+) clonal expansions were stable when followed for up to 5 years. The results of this study demonstrate that the T-cell repertoire of patients with PBC and CREST is characterized by expanded clonal populations of CD8(+) TCRBV3(+) T cells. These clonal expansions provide evidence that stimulation of clonal populations of CD8(+) T cells is associated with the clinical syndrome of PBC with CREST.
原发性胆汁性肝硬化(PBC)患者有时会出现CREST(皮肤钙质沉着、雷诺综合征、食管动力障碍、指(趾)硬化和毛细血管扩张)综合征的临床特征,但这些病症背后假定的自身免疫机制尚不清楚。克隆性扩增的T细胞可能在疾病发病机制中起重要作用。在本研究中,PBC和/或CREST患者中记录到一种T细胞受体β链可变区TCRBV3的过度表达。通过半定量逆转录聚合酶链反应(RT-PCR)证实了TCRBV3基因mRNA的过度表达。通过流式细胞术分析表达TCRBV3的T细胞,其主要为CD8(+),并通过CD69的表达评估含有活化细胞。通过互补决定区3(CDR3)长度多态性分析和T细胞受体CDR3 cDNA测序记录了该群体内克隆性扩增的T细胞。随访长达5年时,TCRBV3(+)克隆性扩增是稳定的。本研究结果表明,PBC和CREST患者的T细胞库以CD8(+) TCRBV3(+) T细胞的克隆群体扩增为特征。这些克隆性扩增提供了证据,表明CD8(+) T细胞克隆群体的刺激与伴有CREST的PBC临床综合征相关。