Immunology Unit, Department of Cell Biology, Physiology and Immunology, Autonomous University of Barcelona, 08193 Bellaterra, Spain; Institute of Biotechnology and Biomedicine, Autonomous University of Barcelona, 08193 Bellaterra, Spain.
Immuno-Oncology Service, Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA; Hepatopancreatobiliary Service, Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
Cell Immunol. 2023 May;387:104707. doi: 10.1016/j.cellimm.2023.104707. Epub 2023 Mar 13.
MHC-I molecules of the HLA-B7 supertype preferentially bind peptides with proline at position 2. HLA-B51:01 and B51:08 present two predominant subpeptidomes, one with Pro2 and hydrophobic residues at P1, and another with Ala2 and Asp enriched at position 1. Here, we present a meta-analysis of the peptidomes presented by molecules of the B7 supertype to investigate the presence of subpeptidomes across different allotypes. Several allotypes presented subpeptidomes differing in the presence of Pro or another residue at P2. The Ala2 subpeptidomes preferred Asp1 except in HLA-B*54:01, where ligands with Ala2 contained Glu1. Sequence alignment and the analysis of crystal structures allowed us to propose positions 45 and 67 of the MHC heavy chain as relevant for the presence of subpeptidomes. Deciphering the principles behind the presence of subpeptidomes could improve our understanding of antigen presentation in other MHC-I molecules. Running title: HLA-B7 supertype subpeptidomes.
MHC-I 分子的 HLA-B7 超型优先结合第 2 位为脯氨酸的肽段。HLA-B51:01 和 B51:08 呈现两种主要的亚肽组，一种是 P1 位为脯氨酸和疏水性残基，另一种是 P1 位为丙氨酸和富含天冬氨酸。在这里，我们对 B7 超型分子呈现的肽组进行了荟萃分析，以研究不同同种异型中是否存在亚肽组。几种同种异型在 P2 存在脯氨酸或其他残基方面呈现不同的亚肽组。Ala2 亚肽组除了 HLA-B*54:01 外，都优先选择天冬氨酸作为 P1 位的配体，而含有 Ala2 的配体含有 Glu1。序列比对和晶体结构分析使我们能够提出 MHC 重链的 45 位和 67 位与亚肽组的存在相关。阐明亚肽组存在的原理可以提高我们对其他 MHC-I 分子中抗原呈递的理解。标题：HLA-B7 超型亚肽组。
