In vitro correlates of cell-mediated immunity in human tonsils after natural or induced Rubella virus infection

The techniques of hemagglutination inhibition and in vitro lymphocyte transformation and the assay of migration inhibitory factor were used for study of the development of rubella antibody activity in serum and tonsillar tissue washings and of the appearance of rubella-specific, cell-mediated immunity in circulating and tonsillar lymphocytes in groups of children who underwent tonsillectomy at various intervals after natural rubella infection, subcutaneous immunization with HPV-77 DE/5 vaccine, or intranasal inoculation with RA27/3 live, attenuated rubella virus vaccine. Antibody response in serum and tonsillar tissue washings was detected regularly after natural infection or immunization. Development of specific cell-mediated immunity in circulating lymphocytes was regularly observed after natural infection and frequently after immunization. Natural infection or intranasal immunization with rubella vaccine resulted in the appearance of cell-mediated immunity in the tonsillar lymphoid tissue, and the response was detectable up to several years after natural infection in several cases. It is significant, however, that the level of cell-mediated immunity in tonsils was conspicuously low after subcutaneous immunization. These data suggest the induction of local cell-mediated immunity in tonsillar lymphoid tissue after local mucosal application of rubella virus.