Centre for Liver Research, National Institute for Health Research Birmingham Liver Biomedical Research Unit, University of Birmingham, Birmingham, UK.
Norwegian PSC Research Center, Department of Transplantation Medicine, Division of Cancer Medicine, Surgery, and Transplantation, Oslo University Hospital Rikshospitalet, Oslo, Norway.
Hepatology. 2016 May;63(5):1608-19. doi: 10.1002/hep.28116. Epub 2015 Sep 30.
Hepatic T-cell infiltrates and a strong genetic human leukocyte antigen association represent characteristic features of various immune-mediated liver diseases. Conceptually the presence of disease-associated antigens is predicted to be reflected in T-cell receptor (TCR) repertoires. Here, we aimed to determine if disease-associated TCRs could be identified in the nonviral chronic liver diseases primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC), and alcoholic liver disease (ALD). We performed high-throughput sequencing of the TCRβ chain complementarity-determining region 3 of liver-infiltrating T cells from PSC (n = 20), PBC (n = 10), and ALD (n = 10) patients, alongside genomic human leukocyte antigen typing. The frequency of TCRβ nucleotide sequences was significantly higher in PSC samples (2.53 ± 0.80, mean ± standard error of the mean) compared to PBC samples (1.13 ± 0.17, P < 0.0001) and ALD samples (0.62 ± 0.10, P < 0.0001). An average clonotype overlap of 0.85% was detected among PSC samples, significantly higher compared to the average overlap of 0.77% seen within the PBC (P = 0.024) and ALD groups (0.40%, P < 0.0001). From eight to 42 clonotypes were uniquely detected in each of the three disease groups (≥30% of the respective patient samples). Multiple, unique sequences using different variable family genes encoded the same amino acid clonotypes, providing additional support for antigen-driven selection. In PSC and PBC, disease-associated clonotypes were detected among patients with human leukocyte antigen susceptibility alleles.
We demonstrate liver-infiltrating disease-associated clonotypes in all three diseases evaluated, and evidence for antigen-driven clonal expansions. Our findings indicate that differential TCR signatures, as determined by high-throughput sequencing, may represent an imprint of distinctive antigenic repertoires present in the different chronic liver diseases; this thereby opens up the prospect of studying disease-relevant T cells in order to better understand and treat liver disease.
肝 T 细胞浸润和强烈的遗传人类白细胞抗原相关性是各种免疫介导的肝病的特征。从概念上讲，疾病相关抗原的存在预计会反映在 T 细胞受体（TCR）谱中。在这里，我们旨在确定是否可以在非病毒性慢性肝病原发性胆汁性胆管炎（PBC）、原发性硬化性胆管炎（PSC）和酒精性肝病（ALD）中鉴定出与疾病相关的 TCR。我们对 20 例 PSC、10 例 PBC 和 10 例 ALD 患者肝浸润 T 细胞的 TCRβ 链互补决定区 3 进行了高通量测序，同时进行了基因组人类白细胞抗原分型。PSC 样本中的 TCRβ 核苷酸序列频率明显高于 PBC 样本（2.53±0.80，平均值±标准误差）和 ALD 样本（0.62±0.10，P<0.0001）。PSC 样本之间检测到平均克隆型重叠率为 0.85%，与 PBC（P=0.024）和 ALD 组（0.40%，P<0.0001）内观察到的平均重叠率 0.77%相比显著更高。在三个疾病组中，每个组都有 8 到 42 个独特的克隆型（≥各自患者样本的 30%）。使用不同的可变家族基因编码相同氨基酸克隆型的多个独特序列提供了抗原驱动选择的额外支持。在 PSC 和 PBC 中，在具有人类白细胞抗原易感等位基因的患者中检测到与疾病相关的克隆型。
我们在所有三种评估的疾病中均证明存在肝浸润性疾病相关克隆型，以及抗原驱动的克隆扩增证据。我们的研究结果表明，通过高通量测序确定的差异 TCR 特征可能代表存在于不同慢性肝病中的独特抗原库的印记；这为研究与疾病相关的 T 细胞以更好地理解和治疗肝病开辟了前景。
