Early interactions of human herpesvirus 6 with lymphoid cells: Role of membrane protein components and glycosaminoglycans in virus binding

Abstract

A microassay was developed to detect human herpesvirus 6 (HHV-6) binding to its cellular receptor using flow cytometry. Comparable results were obtained either by using HHV-6 preparations conjugated with fluorescein isothiocyanate or by indirect immunofluorescent labeling of membrane-bound virus using as primary antibody a monoclonal antibody specific for the HHV-6 gp60/110 envelope glycoprotein. Virus attachment to the plasma membrane was specific and saturable. As expected, among cell lines of various origin, maximum binding was detected on human T-lymphoid cells (HSB-2). Papain digestion of HSB-2 cells prevented HHV-6 attachment and reduced significantly virus infection, indicating the involvement of a protein-based receptor in the attachment step. After removal of the protease, virus receptors were resynthesized and their regeneration was prevented partially by cycloheximide, an inhibitor of protein synthesis. Unexpectedly, only high concentrations (mg/ml) of soluble heparan sulfate and heparin inhibited HHV-6 binding and infection. Under the same conditions, few micrograms (per ml) of heparin suppressed completely herpes simplex type 1 (HSV-1) attachment to the same cell line. Treatment of HSB-2 cells with heparitinase and heparinase, at doses that reduced significantly HSV-1 attachment, had little effect on HHV-6 binding to the cell membrane, indicating a different requirement of heparan sulfate-containing glycosaminoglycans for the two herpesviruses. These data suggest that protein components of the cellular membrane play an essential role in HHV-6 binding and infection while heparan sulfate-glycos-aminoglycans appear to be involved only partially in virus-receptor interaction.

Herpesviruses and heparan sulfate: an intimate relationship in aid of viral entry

“…It is unclear whether HHV-6 interacts with cell surface heparan sulfate. Binding of virus to T cells and infection of the cells are only partially inhibited by heparin or heparan sulfate and only at high concentrations (24). The binding of EBV to B cells can be explained by interactions of gp350/220 with CD21 and gH-gL-gp42 with class II MHC molecules (25).…”

Myocardial Oedema as a Consequence of Viral Infection and Persistence—A Narrative Review with Focus on COVID-19 and Post COVID Sequelae

“…Parvovirus B19 heparan sulphate, sialic acid [405] Human herpesvirus 1, 6 heparan sulphate, syndecan-1 [406,407] Epstein-Barr virus glycoproteins, hyaluronan synthesis [408,409] Human cytomegalovirus heparan sulphate [410,411] Enteroviruses heparan sulphate, P-selectin glycoprotein ligand-1, sialylated glycan [412][413][414] Adenovirus heparan sulphate, sialic acid [415][416][417] Hepatitis C virus heparan sulphate, syndecan-1 [418,419] SARS-CoV-2 heparan sulphate proteoglycans [241,420] Influenza virus sialic acids, hyaluronan synthesis [415,421]…”

Myocardial Oedema as a Consequence of Viral Infection and Persistence – a Narrative Review with Focus on COVID-19 and Post COVID Sequelae

“…heparan sulphate, sialic acid [381] Human herpesvirus 1, 6 heparan sulphate, syndecan-1 [382,383] Epstein-Barr virus glycoproteins, hyaluronan synthesis [384,385] Human cytomegalovirus heparan sulphate [386,387] Enteroviruses heparan sulphate, P-selectin glycoprotein ligand-1, sialylated glycan [388][389][390] Adenovirus heparan sulphate, sialic acid [391][392][393] Hepatitis C virus heparan sulphate, syndecan-1 [394,395] SARS-CoV-2 heparan sulphate proteoglycans [223,396] Influenza virus sialic acids, hyaluronan synthesis [391,397]…”