Cell-Mediated Immunity to Varicella-Zoster Virus: In Vitro Lymphocyte Responses

Abstract
Lymphocytes obtained from nonimmune children and from adults after an attack of herpes zoster were incubated with antigens of varicella-zoster virus. Lymphocyte transformation, measured by the incorporation of tritiated thymidine, was found to reflect specific immunity to the varicella-zoster virus, although the degree of transformation could not be related to the activity of the disease. Production of interferon was dependent on the method of preparation of lymphocytes and was not related to disease activity or to the immune status of the donors. The interferon-producing and DNA-synthesizing activities could be dissociated by antigen dilution, further suggesting that production of interferon was nonspecific. The extent of immune-specific incorporation of tritiated thymidine by lymphocytes could be increased by incubation of the cultures in the presence of fetal calf serum. Cellular immunity to the varicella-zoster virus can be studied in relation to the risk of infection in immunosuppressed patients, and such work may lead to a better understanding of the phenomenon of latency.