9MCX

CRYSTAL STRUCTURE OF HUMAN IGG1 FC FRAGMENT-FC-GAMMA RECEPTOR IIA COMPLEX H131 VARIANT

9MCX の概要

• エントリーDOI: 10.2210/pdb9mcx/pdb
• 分子名称: Immunoglobulin gamma-1 heavy chain Fc fragment, Low affinity immunoglobulin gamma Fc region receptor II-a H131 variant, beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-[alpha-L-fucopyranose-(1-6)]2-acetamido-2-deoxy-beta-D-glucopyranose, ... (6 entities in total)
• 機能のキーワード: immunoglobulin, igg1, immune system, immunoglobulin-like beta sandwich, fc fragment, fc gamma receptor iia, cd32a
• 由来する生物種: Homo sapiens (human); 詳細
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 73486.13

構造登録者

Tolbert, W.D.,Pazgier, M. (登録日: 2024-12-05, 公開日: 2025-12-03, 最終更新日: 2026-01-07)

主引用文献

Tolbert, W.D.,Nhan, P.B.,Conley, H.E.,Ge, X.,Chandravanshi, M.,Lee, M.,Veilleux, J.,Korzeniowski, M.,Gottumukkala, S.,Ackerman, M.E.,Pollara, J.,Pazgier, M.
Cross-species analysis of Fc gamma RIIa/b (CD32a/b) polymorphisms at position 131: structural and functional insights into the mechanism of IgG- mediated phagocytosis in human and macaque.
Front Immunol, 16:1726068-1726068, 2025

PubMed Abstract: Antibodies play a critical role in immunity in part by mediating clearance of pathogens and infected cells by antibody-dependent cellular phagocytosis (ADCP) through engagement of Fc gamma receptors (FcγRs) on innate immune cells. Among these, FcγRIIa (CD32a) is a key activating receptor expressed on macrophages, dendritic cells, and other antigen-presenting cells. Its affinity for IgG and ability to mediate ADCP is influenced by allelic polymorphisms. In humans, a single amino acid polymorphism at position 131, where histidine (H) is substituted with arginine (R), leads to decreased IgG1 and IgG2 subclass binding affinity and, consequently, lower efficiency of phagocytic responses. Rhesus macaques (), which are widely used as nonhuman primate models, exhibit a similar polymorphism at position 131 of FcγRIIa, but with arginine replaced by proline (P). Here, we investigated structure-function relationships associated with the FcγRIIa polymorphism at position 131 in both species, specifically with respect to IgG1 and IgG2.

PubMed: 41445744
DOI: 10.3389/fimmu.2025.1726068

実験手法

X-RAY DIFFRACTION (2.38 Å)