Envelope glycoprotein B (gB) (HCMV gB)

Human cytomegalovirus (HCMV) glycoprotein B (gB) is a class III viral fusion protein that is essential for the virus to enter host cells and spread directly between them [2, 13]. It is encoded by the UL55 gene and exists as a disulfide-linked homodimer on the viral envelope and the surface of infected cells [15, 16]. The cell-associated form of gB is particularly significant in vaccine research, as antibody binding to this native, membrane-bound conformation has been identified as a key correlate of protection against infection, whereas binding to soluble recombinant forms often does not predict efficacy [5]. gB mediates the fusion of the viral envelope with the host cell membrane by interacting with the gH/gL complex and various cellular receptors, such as PDGFR-alpha and integrins [10, 14, 15]. Therapeutic efforts targeting gB include subunit vaccines like gB/MF59 and monoclonal antibodies like TRL345, which aim to neutralize the virus and prevent severe outcomes like congenital CMV and transplant-related disease [1, 6]. However, the protein's extensive glycosylation and the presence of non-neutralizing decoy epitopes present significant challenges for drug and vaccine development [14, 18].

Other names

gBgpUL55UL55Human cytomegalovirus glycoprotein BCell-associated gBCytomegalovirus glycoprotein B

Inhibition of viral-host membrane fusion and cell-to-cell spread by blocking conformational changes or receptor interactions.