9ELU

CRYSTAL STRUCTURE OF RHESUS MACAQUE (MACACA MULATTA) IGG1 FC FRAGMENT- FC-GAMMA RECEPTOR IIA COMPLEX P131 VARIANT

Summary for 9ELU

• Entry DOI: 10.2210/pdb9elu/pdb
• Descriptor: IgG1 Fc, IgG receptor IIA (CD32A) P131 variant Fc fragment, beta-D-galactopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-2)-alpha-D-mannopyranose-(1-6)-[2-acetamido-2-deoxy-beta-D-glucopyranose-(1-2)-alpha-D-mannopyranose-(1-3)]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, ... (7 entities in total)
• Functional Keywords: immunoglobulin, igg1, immune system, immunoglobulin-like beta sandwich, fc fragment, fc gamma receptor iia, cd32a
• Biological source: Macaca mulatta (Rhesus monkey); More
• Total number of polymer chains: 3
• Total formula weight: 73555.03

Authors

Tolbert, W.D.,Pazgier, M. (deposition date: 2024-12-05, release date: 2025-12-03, Last modification date: 2026-01-07)

Primary citation

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

Experimental method

X-RAY DIFFRACTION (2.65 Å)