直接定量测量HLA特异性抗体与分离的HLA蛋白相互作用的动力学。

Direct quantitative measurement of the kinetics of HLA-specific antibody interactions with isolated HLA proteins.

作者信息

Daga Sunil, Moyse Harry, Briggs David, Lowe David, Evans Neil, Jones James, Buchli Rico, McMurtrey Curtis, Mulder Arend, Hildebrand William, Claas Frans, Higgins Robert, Mitchell Daniel A, Zehnder Daniel

机构信息

Renal Department, UHCW NHS Trust, Coventry, UK; Renal Department, St. James's University Hospital, Leeds, UK; Warwick Medical School, University of Warwick, Coventry, UK.

School of Engineering, University of Warwick, Coventry, UK.

出版信息

Hum Immunol. 2018 Feb;79(2):122-128. doi: 10.1016/j.humimm.2017.10.012. Epub 2017 Oct 31.

DOI:10.1016/j.humimm.2017.10.012

PMID:29097266

Abstract

HLA specific antibodies vary in their pathogenicity and this is likely to be the net effect of constant chain usage, quantity, specificity, and affinity. Here we have measured the affinity of human monoclonal antibodies for a range of HLA proteins. Purified antibodies and ligands allowed dynamic interactions to be measured directly by surface plasmon resonance. Physiochemical differences between pairs of ligands were quantified using electrostatic mismatch and hydrophobic mismatch scores. All antibodies were characterized by fast on-rates and slow off rates but with a wide range of association rates (k 3.63-24.25 × 10 per mol per second) and dissociation rates (k, 0.99-10.93 × 10 per second). Dissociation constants (K) ranged from 5.9 × 10 M to 3.0 × 10 M. SN320G6 has approximately a twenty-fold greater affinity for HLA A2 compared with SN607D8, but has a similar affinity for HLA-A2 and B57. In contrast, SN607D8 has greater than a twofold greater affinity for HLA-A2 compared with A68. Similarly, WK1D12 has about a threefold greater affinity for HLA-B27 compared with B7. The higher affinity interactions correlate with the specificity of stimulating antigen. This is the first study to directly measure the binding kinetics and affinity constants for human alloantibodies against HLA.

摘要

HLA特异性抗体的致病性各不相同，这可能是恒定链使用情况、数量、特异性和亲和力的综合作用结果。在此，我们测定了一系列人单克隆抗体与多种HLA蛋白的亲和力。纯化的抗体和配体使得能够通过表面等离子体共振直接测量动态相互作用。利用静电错配和疏水错配分数对配体对之间的物理化学差异进行了量化。所有抗体的特征都是结合速率快、解离速率慢，但结合速率（k，3.63 - 24.25×10⁻⁵mol⁻¹·s⁻¹）和解离速率（k，0.99 - 10.93×10⁻³s⁻¹）范围很广。解离常数（Kd）范围从5.9×10⁻⁹M到3.0×10⁻⁷M。与SN607D8相比，SN320G6对HLA A2的亲和力大约高20倍，但对HLA - A2和B57的亲和力相似。相比之下，与A68相比，SN607D8对HLA - A2的亲和力高两倍以上。同样，与B7相比，WK1D12对HLA - B27的亲和力大约高3倍。较高亲和力的相互作用与刺激抗原的特异性相关。这是第一项直接测量人同种异体抗体与HLA结合动力学和亲和力常数的研究。