Development and Characteristics of In-Vitro Correlates of Cellular Immunity to Rubella Virus in the Systemic and Mucosal Sites in Guinea Pigs

Abstract The development of rubella-specific cell-mediated immunity (CMI) in splenic and bronchial lymphoid cells and antibody activity in serum and bronchial washings was studied in guinea pigs after subcutaneous or intranasal inoculation with live attenuated HPV-77 DE/5, RA27/3 rubella vaccines or live Brown strain of rubella virus. The techniques of hemagglutination inhibition, in vitro lymphocyte transformation, and assay of migration inhibitory factor with rubella virus as the antigen were employed to determine antibody and CMI in the systemic and secretory sites. Subcutaneous immunization resulted in regular appearance of serum antibody response. However, no antibody was detected in bronchial washings. Intranasal administration of the virus preparation resulted in little or no antibody response in the serum or respiratory tract. The CMI response after subcutaneous administration of rubella virus was characterized by the specific induction of lymphocyte transformation and migration inhibitory factor activity in the spleen cells without any detectable response in the bronchial lymphoid cells. Intranasal immunization resulted in the appearance of migration inhibitory factor activity in the bronchial cells with little or no response in the spleen cells. The CMI responses were initially detected 2 weeks after immunization. Peak responses were often found at 4 weeks, and no specific migration inhibitory factor or lymphocyte transformation activity was detected after 6 weeks. The results of this study suggest the development of local cellular immune response in the respiratory tract after local application of rubella virus.