To further delineate the immune responses that protect against serious primary varicella zoster virus (VZV) infection and inhibit viral reactivation, antibody responses and T lymphocyte reactivity to three major VZV glycoproteins, gpI, gpII, and gpIII, were studied. Individual viral glycoproteins were purified using murine monoclonal antibodies. Cellular immunity was measured by lymphocyte proliferation. Antibody responses were tested in enzyme-linked immunosorbent assays. Individual glycoproteins induced VZV-specific proliferation by mononuclear cells from 15 of 20 immune subjects. Serologic responses to the VZV glycoproteins occurred in 16 of 20 immune subjects. Of note, gpII served as a potent T and B cell antigen during both acute infection and convalescence. Cell-mediated responses to the glycoprotein antigens represented proliferation by T lymphocytes and required antigen presentation by adherent mononuclear cells. These findings indicate that virally encoded glycoproteins contain epitopes that stimulate VZV-specific cellular and humoral immune responses.