Functional Proteomics Laboratory, SingMass National Laboratory, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A∗STAR), Singapore 138673, Singapore.
Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore 117545, Singapore; Immunology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, 5 Science Drive 2, Singapore 117545, Singapore.
Cell Rep Methods. 2023 Sep 25;3(9):100569. doi: 10.1016/j.crmeth.2023.100569. Epub 2023 Aug 30.
Alloantibody recognition of donor human leukocyte antigen (HLA) is associated with poor clinical transplantation outcomes. However, the molecular and structural basis for the alloantibody-HLA interaction is not well understood. Here, we used a hybrid structural modeling approach on a previously studied alloantibody-HLA interacting pair with inputs from ab initio, in silico, and in vitro data. Highly reproducible cross-linking mass spectrometry data were obtained with both discovery- and targeted mass spectrometry-based approaches approaches. The cross-link information was then used together with predicted antibody F structure, predicted antibody paratope, and in silico-predicted interacting surface to model the antibody-HLA interaction. This hybrid structural modeling approach closely recapitulates the key interacting residues from a previously solved crystal structure of an alloantibody-HLA-A∗11:01 pair. These results suggest that a predictive-based hybrid structural modeling approach supplemented with cross-linking mass spectrometry data can provide functionally relevant structural models to understand the structural basis of antibody-HLA mismatch in transplantation.
同种异体抗体对供体人类白细胞抗原 (HLA) 的识别与不良的临床移植结果相关。然而，同种异体抗体-HLA 相互作用的分子和结构基础尚未得到很好的理解。在这里，我们使用了一种混合结构建模方法，该方法使用了从头计算、计算机模拟和体外数据作为输入，对先前研究过的同种异体抗体-HLA 相互作用对进行了研究。使用基于发现和靶向质谱的方法获得了高度可重现的交联质谱数据。然后，将交联信息与预测的抗体 F 结构、预测的抗体结合位和计算机预测的相互作用表面一起用于构建抗体-HLA 相互作用模型。这种混合结构建模方法紧密地再现了之前解决的同种异体抗体-HLA-A∗11:01 对晶体结构的关键相互作用残基。这些结果表明，基于预测的混合结构建模方法结合交联质谱数据，可以提供功能相关的结构模型，以了解移植中抗体-HLA 不匹配的结构基础。
