Pediatric Gastroenterology Unit, Edmond and Lily Safra Children's Hospital, Sheba Medical Centre, Ramat Gan, Israel.
Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Front Immunol. 2020 Feb 6;11:109. doi: 10.3389/fimmu.2020.00109. eCollection 2020.
Patients with loss-of-function mutations in IL10 or IL10 receptor (IL10R) genes develop severe, medical-refractory, infantile-onset inflammatory bowel disease (IBD). We have previously reported significant alterations in innate and adaptive immune responses in these patients. Next generation sequencing platforms enable a comprehensive assessment of T cell receptor (TCR) and B cell receptor (BCR) repertoire patterns. We aimed to characterize TCR and BCR features in peripheral blood of patients with deleterious IL10 signaling defects. DNA was isolated from blood of seven patients with IL10R mutations and one with an IL10 mutation, along with eight controls, and subjected to next generation sequencing of and loci. A significant increase in clonality was observed in both TCR and BCR repertoires in circulating lymphocytes of IL10/IL10R-deficient patients, but to a much greater extent in T cells. Furthermore, short CDR3β length and altered hydrophobicity were demonstrated in T cells of patients, but not in B cells, secondary to lower rates of insertions of nucleotides, but not deletions, at the V-, D-, or J-junctions. We were unable to observe specific T or B clones that were limited only to the patients or among controls. Moreover, the expanded T cells clones were unique to each patient. In conclusion, next generation sequencing of the TCR and BCR is a powerful tool for characterizing the adaptive immune cell phenotype and function in immune-mediated disorders. The oligoclonality observed among IL10/IL10R-deficient patients may suggest specialization of unique clones that likely have a role in mediating tissue damage. Nevertheless, the lack of shared clones between patients provides another piece of evidence that the adaptive immune response in IBD is not triggered against common antigens. Additional studies are required to define the specific antigens that interact with the expanded IL10/IL10R-deficient clones.
患有白细胞介素 10（IL10）或白细胞介素 10 受体（IL10R）基因突变的患者会发展为严重的、医学难治性、婴儿期发病的炎症性肠病（IBD）。我们之前报道过这些患者固有和适应性免疫反应的显著改变。下一代测序平台可全面评估 T 细胞受体（TCR）和 B 细胞受体（BCR）库模式。我们旨在描述具有有害 IL10 信号缺陷的患者外周血中的 TCR 和 BCR 特征。从 7 名 IL10R 突变和 1 名 IL10 突变患者以及 8 名对照者的血液中提取 DNA，并对 和 基因座进行下一代测序。在 IL10/IL10R 缺陷患者的循环淋巴细胞中，无论是 TCR 还是 BCR 库，均观察到克隆性显著增加，但 T 细胞增加更为明显。此外，由于 V 、 D 或 J 连接处核苷酸插入率降低而非缺失率降低，患者的 T 细胞中 CDR3β 长度变短且疏水性改变，但 B 细胞中无此现象。我们无法观察到仅局限于患者或对照组中的特定 T 或 B 克隆。此外，扩增的 T 细胞克隆对每个患者均是独特的。总之，TCR 和 BCR 的下一代测序是一种强大的工具，可用于描述免疫介导性疾病中适应性免疫细胞表型和功能。在 IL10/IL10R 缺陷患者中观察到的寡克隆性可能提示独特克隆的专业化，这些克隆可能在介导组织损伤中起作用。然而，患者之间缺乏共享克隆为另一个证据，即 IBD 中的适应性免疫反应并非针对共同抗原而触发。需要进一步研究来确定与扩增的 IL10/IL10R 缺陷克隆相互作用的特定抗原。
