Induction of neutralizing antibody against varicella-zoster virus (VZV) by VZV gp3 and cross-reactivity between VZV gp3 and herpes simplex viruses gB.

Glycoprotein gp3 (64K) is one of the major proteins specified by varicella-zoster virus (VZV). This glycoprotein was purified on an immunoadsorbent consisting of monoclonal antibody (clone 8) against gp3 linked to protein A-Sepharose. Rabbits were then immunized with the purified antigen to obtain monospecific antisera against gp3. The monospecific antisera and monoclonal antibody immunoprecipitated polypeptides with the same molecular weights of approximately 64,000 (64K), 106K, and 116K from a lysate of labeled cells infected with VZV. The monoclonal antibodies against gp3 did not have neutralizing activity against VZV, but anti-gp3 monospecific sera neutralized VZV infectivity. The antigenic relation of VZV to herpes simplex virus (HSV) was investigated by the immunofluorescent test, immunoprecipitation followed by analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the neutralizing antibody test with monoclonal antibodies and monospecific antisera. In the indirect immunofluorescent test, the cytoplasm of cells infected with HSV-type 1 or HSV-type 2 was stained with anti-gp3 monospecific antiserum but not with anti-gp3 monoclonal antibodies. This serum also precipitated the polypeptides of HSV-type 1 and HSV-type 2 with molecular weight of approximately 120,000, possibly corresponding to gB of HSV-1 or HSV-2, and this immunoprecipitation was blocked by anti-gB monoclonal antibody. However, anti-gp3 monospecific antisera did not neutralize either HSV-type 1 or HSV-type 2 infectivity. These results suggest that gp3 induces neutralizing antibody against VZV and that it also has a cross-reacting antigenic determinant with gB of HSV.

Processing of virus-specific glycoproteins of varicella zoster virus.

Monoclonal antibodies to varicella zoster virus (VZV) glycoproteins were used to study the processing of three glycoproteins with molecular weights of 83K-94K (gp 2), 64K (gp 3), and 55K (gp 5). Immunoprecipitation experiments performed with VZV-infected cells, pulse labeled with [3H]glucosamine in the presence of tunicamycin, suggest that O-linked oligosaccharide is present on the glycoprotein of gp 2. Use of the enzyme endo-beta-N-acetylglucosaminidase H revealed that the fully processed form of gp 3 had high-mannose type and that of gp 5 had only complex type of N-linked oligosaccharides. Experiments with monensin suggest that the precursor form (116K) of gp 3 is cleaved during the processing from Golgi apparatus to cell surface membrane. The extension of O-linked oligosaccharide chain and the complex type of N-linked oligosaccharide chains also occurs during this processing.