Structural basis for HCMV Pentamer receptor recognition and antibody neutralization

Sci Adv. 2022 Mar 11;8(10):eabm2536. doi: 10.1126/sciadv.abm2536. Epub 2022 Mar 11.

Abstract

Human cytomegalovirus (HCMV) represents the viral leading cause of congenital birth defects and uses the gH/gL/UL128-130-131A complex (Pentamer) to enter different cell types, including epithelial and endothelial cells. Upon infection, Pentamer elicits the most potent neutralizing response against HCMV, representing a key vaccine candidate. Despite its relevance, the structural basis for Pentamer receptor recognition and antibody neutralization is largely unknown. Here, we determine the structures of Pentamer bound to neuropilin 2 (NRP2) and a set of potent neutralizing antibodies against HCMV. Moreover, we identify thrombomodulin (THBD) as a functional HCMV receptor and determine the structures of the Pentamer-THBD complex. Unexpectedly, both NRP2 and THBD also promote dimerization of Pentamer. Our results provide a framework for understanding HCMV receptor engagement, cell entry, antibody neutralization, and outline strategies for antiviral therapies against HCMV.