Tumor Immunotherapy Program, Campbell Family Institute for Breast Cancer Research, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada.
Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada.
Nat Biotechnol. 2021 Aug;39(8):958-967. doi: 10.1038/s41587-021-00836-4. Epub 2021 Mar 1.
Peptide-major histocompatibility complex (pMHC) multimers enable the detection of antigen-specific T cells in studies ranging from vaccine efficacy to cancer immunotherapy. However, this technology is unreliable when applied to pMHC class II for the detection of CD4 T cells. Here, using a combination of molecular biological and immunological techniques, we cloned sequences encoding human leukocyte antigen (HLA)-DP, HLA-DQ and HLA-DR molecules with enhanced CD4 binding affinity (with a K of 8.9 ± 1.1 µM between CD4 and affinity-matured HLA-DP4) and produced affinity-matured class II dimers that stain antigen-specific T cells better than conventional multimers in both in vitro and ex vivo analyses. Using a comprehensive library of dimers for HLA-DP4, which is the most frequent HLA allele in many ancestry groups, we mapped 103 HLA-DP4-restricted epitopes derived from diverse tumor-associated antigens and cloned the cognate T-cell antigen receptor (TCR) genes from in vitro-stimulated CD4 T cells. The availability of affinity-matured class II dimers across HLA-DP, HLA-DQ and HLA-DR alleles will aid in the investigation of human CD4 T-cell responses.
肽-主要组织相容性复合体 (pMHC) 多聚体可用于检测从疫苗效力到癌症免疫疗法等研究中的抗原特异性 T 细胞。然而，当应用于 pMHC II 类来检测 CD4 T 细胞时，该技术不可靠。在这里，我们使用分子生物学和免疫学技术的组合，克隆了编码人类白细胞抗原 (HLA)-DP、HLA-DQ 和 HLA-DR 分子的序列，这些分子与增强的 CD4 结合亲和力（CD4 与亲和力成熟的 HLA-DP4 之间的 Kd 为 8.9±1.1µM），并产生了亲和力成熟的 II 类二聚体，与传统多聚体相比，在体外和体内分析中更好地染色抗原特异性 T 细胞。使用 HLA-DP4 的综合二聚体文库，该文库是许多种族群体中最常见的 HLA 等位基因，我们绘制了来自多种肿瘤相关抗原的 103 个 HLA-DP4 限制性表位，并从体外刺激的 CD4 T 细胞中克隆了同源 T 细胞抗原受体 (TCR) 基因。具有亲和力成熟的 II 类二聚体的 HLA-DP、HLA-DQ 和 HLA-DR 等位基因的可用性将有助于研究人类 CD4 T 细胞反应。
