Cell-mediated immune responses after immunization of healthy seronegative children with varicella vaccine: kinetics and specificity.

Humoral and cell-mediated immune responses were determined in seronegative children immunized with live attenuated Oka strain varicella vaccine. At 2 weeks after immunization, 80% of children had detectable lymphocyte proliferation to varicella-zoster virus (VZV) antigens, while only 40% had antibodies to VZV as detected by ELISA. By 6 weeks after immunization, 97% of children seroconverted, and 95% of these responded to VZV antigens in the proliferation assay. A high proportion of immunized children also responded in the proliferation assay to purified glycoproteins I, II, and III of VZV. These results indicate that most children develop a broad cell-mediated immune response to VZV antigens within weeks after immunization with varicella vaccine.