Abstract: | Fluorescence antibodies (FA) were titrated in human sera against antigens synthesized in four different infected cell lines: SIRC, RK-13, Vero and BHK-21. The cells infected in suspension by rubella virus attained the optimal concentration of fluorescence staining antigen earlier, fluorescence was more intensive and the titers of the tested human sera were slightly higher than in monolayer cell cultures. FA titers were high and they were correlated with the antibody titers obtained by hemagglutination-inhibition test. Some practical implications of these findings are discussed. |