Antigenic differences between the membrane antigen polypeptides determined by different EB virus isolates

Comparative immunogenicity studies on Epstein-Barr virus membrane antigen (MA) gp340 with novel adjuvants in mice, rabbits, and cotton-top tamarins

The effectiveness of immunisation of mice, rabbits, and cotton-top tamarins with small amounts of EB virus MA glycoprotein gp340 , incorporated into artificial liposomes, has been compared using various routes of injection with or without additional adjuvants. Liposomes containing gp340 gave specific high titre antibodies after i.p. or i.v. administration, and the addition of lipid A to the liposomes resulted in a significant enhancement of the response. Antibodies generated by the above procedure were virus neutralising and bound gp340 specifically. These findings indicate an advantageous approach for use with a prototype vaccine for the prevention of EB virus infection.

Purified Epstein-Barr virus Mr 340,000 glycoprotein induces potent virus-neutralizing antibodies when incorporated in liposomes

The purified Mr 340,000 glycoprotein component of Epstein-Barr (EB) virus-induced membrane antigen complex incorporated into liposomes was shown to be a potent immunogen in mice. High-titer antisera were induced that (i) are specific for membrane antigen components without absorption, (ii) bind the antigens induced by three different EB virus isolates, and (iii) neutralize the ability of the virus to transform fetal cord blood lymphocytes in vitro. The development of this immunogenic form of purified antigen provides an important step towards a potential subunit vaccine against Epstein-Barr virus infection.

Neutralization of lymphocyte immortalization by different strains of Epstein-Barr virus with a murine monoclonal antibody

A murine monoclonal antibody was raised against the B95-8 strain of Epstein-Barr virus (EBV), which was isolated from a case of mononucleosis after blood transfusion (Hoffman et al. Proc. Natl. Acad. Sci. U.S.A. 77:2979, 1980). We provide evidence that neutralization of immortalization by this monoclonal antibody is virus specific, since its potency was inversely related to the dose of challenge virus. Furthermore, the monoclonal antibody recognized antigens on viruses grown in human as well as in marmoset cells. We show that this monoclonal antibody neutralized three other transforming strains of EBV originating, respectively, from American patients with mononucleosis and fatal polyclonal lymphoma and from an African child with Burkitt lymphoma. However the antibody did not neutralize or detect antigens by immunofluorescence in the W91 strain of EBV. The hybridoma antibody did neutralize other EBV strains derived from the same Burkitt lymphoma cell line (Nyevu), as was the case with the W91 strain. This monoclonal antibody provides clear evidence of antigenic differences on the surface of EBVs and will ultimately prove useful in defining the antigenic site on EBV which elicits neutralizing antibody.

Quantification of an Epstein-Barr virus-associated membrane antigen component

A method is described for the preparation of a 125I-labelled membrane antigen (MA) component (gp340) from B95-8 cell membranes using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Good yields of antigenic material were obtained when renaturation of the [125I]gp340 was carried out by removal of SDS in the presence of urea and subsequent removal of the urea. The availability of purified, radiolabelled gp340 has provided the essential basis for the development of a radioimmunoassay which, for the first time, permits quantification of this antigen. The assay has been used to demonstrate that cell membrane MA is a better source of gp340 for large-scale work than is the Epstein-Barr virus envelope and to measure the increase in expression of gp340 following treatment of cells with 12-O-tetradecanoyl-phorbol-13-acetate (TPA).