Prediction of HLA class I-restricted T-cell epitopes of islet autoantigen combined with binding and dissociation assays
Prediction of HLA class I-restricted T-cell epitopes of islet autoantigen combined with binding and dissociation assays
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结合结合和解离测定预测胰岛自身抗原的 HLA I 类限制性 T 细胞表位
DOI：
10.3109/08916934.2011.622014
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发表时间：
2012-03-01
期刊：
影响因子：
3.5
通讯作者：
Yang, Tao
中科院分区：
文献类型：
--
作者：
Wu, Xiangmei;Xu, Xinyu;Yang, Tao
识别人类白细胞抗原(HLA)/T细胞受体(TCR)复合体识别的同源多肽有助于深入了解1型糖尿病(T1D)的发病过程。我们假设单靠与人类白细胞抗原的结合分析不足以衡量多肽的亲和力。锌转运蛋白-8(ZnT8)是近年来出现的一种新的、主要的人类自身抗原。因此，我们的目标是通过结合和解离两种方法来鉴定人类白细胞抗原A2限制性的锌T8表位。用人类白细胞抗原I类多肽亲和力算法预测与人类白细胞抗原A2结合的候选多肽。我们用结合和解离实验分析了7个候选β细胞自身抗原的15个表位和8个预测的候选多肽。采用干扰素-γELISpot方法，检测了新发的T1D患者和健康对照的外周血单个核细胞(PBMC)对7个已报道的表位和8个候选的锌多肽的体外反应性。我们在最近报道的7个表位中有5个在中国的T1D患者中发现。在预测的8个多肽中，ZnT8153-161与人类白细胞抗原-A*0201具有较强的亲和力和最低的解离率。我们在8名T1D患者中的3名患者中确定它是一种新的人类白细胞抗原-A*0201限制性T细胞表位。我们的结论是，ZnT8153-161是一种新的人类白细胞抗原A*0201限制性T细胞表位。我们没有观察到细胞毒性T细胞应答与多肽/−*0201复合体稳定性之间的显著相关性(P=0.3，R=HLA0.5)。然而，基于亲和力和解离率的多肽的选择可能有助于识别候选的CTL表位。因此，我们可以最大限度地减少从感兴趣的抗原中识别T细胞表位的实验次数。
Identification of cognate peptides recognized by human leucocyte antigen (HLA)/T cell receptor (TCR) complex provides insight into the pathogenic process of type 1 diabetes (T1D). We hypothesize that HLA-binding assays alone are inadequate metrics for the affinity of peptides. Zinc transporter-8 (ZnT8) has emerged in recent years as a novel, major, human autoantigen. Therefore, we aim to identify the HLA-A2-restricted ZnT8 epitopes using both binding and dissociation assays. HLA class I peptide affinity algorithms were used to predict candidate ZnT8 peptides that bind to HLA-A2. We analyzed 15 reported epitopes of seven β-cell candidate autoantigens and eight predicted candidate ZnT8 peptides using binding and dissociation assays. Using IFN-γ ELISpot assay, we tested peripheral blood mononuclear cells (PBMCs) from recent-onset T1D patients and healthy controls for reactivity to seven reported epitopes and eight candidate ZnT8 peptides directly ex vivo. We found five of seven recently reported epitopes in Chinese T1D patients. Of the eight predicted ZnT8 peptides, ZnT8153–161 had a strong binding affinity and the lowest dissociation rate to HLA-A*0201. We identified it as a novel HLA-A*0201-restricted T-cell epitope in three of eight T1D patients. We conclude that ZnT8153–161 is a novel HLA-A*0201-restricted T-cell epitope. We did not observe a significant correlation (P = 0.3, R = − 0.5) between cytotoxic T cell (CTL) response and peptide/HLA*0201 complex stability. However, selection of peptides based on affinity and their dissociation rate may be helpful for the identification of candidate CTL epitopes. Thus, we can minimize the number of experiments for the identification of T-cell epitopes from interesting antigens.