The Epstein-Barr Virus Receptor is Distinct from the C3 Receptor

Abstract

SUMMARYPolyvalent serum directed against C3 receptors was employed in an attempt to block Epstein-Barr virus (EBV) binding to virus receptor-containing cell lines. The serum eliminated 90 ~ of virus binding to Daudi and B JAB, lines which express only the C3d receptor. Raji and Ramos cells, which express the C3d, C3b and C3bi receptors, still adsorbed 70 ~ of their virus capacity in the presence of excess antiserum. These effects were independent of the virus strain. In the light of previous reports, these data imply that, although the two receptors, EBV and C3d, are closely associated, the binding sites of EBV and complement are distinct. Additionally, an unusual EBV substrain-specific receptor found on U698 and P3HR-1/ASNP lines was shown to be independent of complement receptors.

Epstein--Barr Virus Binding to Virus-carrying Cell Lines is Enhanced in the Presence of C3 and C3d

“…the P3HR-l-derived substrain . It was previously seen that polyvalent anti-C3 receptor sera did not affect virus binding to these lines (Wells et al, 1983). Incubating with complement components also did not alter the binding profiles (Fig.…”

“…Antibodies directed against cell-bound complement inhibit virus binding suggesting a close interaction. However, anti-C3 receptor serum, which completely eliminates C3 adsorption, only partially interferes with EBV binding (Wells et al, 1983). Thus, we are faced with a receptor complex in which the two sites are closely linked but separate.…”

“…Two observations must be reconciled: that EBV binding can be partially inhibited by anti-C3 receptor sera even in the absence of complement binding (Wells et al, 1983), and that the presence of C3d may enhance virus binding. It may be postulated that C3 is present in the viral envelope and the virus binds via the molecule.…”

“…Glaser et al (1977) have constructed :~ Relative levels of virus binding compared to Raji cells (Jonsson et al, 1982;Wells et al, 1983), with greater than 90~ of the cells demonstrating binding (Wells et al, 1981b).…”

“…§ Relative levels of complement binding compared to Raji cells (J~nsson et al, 1982;Wells et al, 1983), with greater than 85% of the cells demonstrating binding (Jonsson et al, 1982;A. Wells et al, unpublished results).…”