Antibody response to wild rubella virus structural proteins following immunization with RA 27/3 live attenuated vaccine.

Antibody response to individual structural proteins (E1, E2, and C) of the M-33 wild rubella virus strain was assayed by an immunoblot technique in 12 girls, following immunization with RA 27/3 live attenuated rubella vaccine. Of the 12 immunized subjects, before vaccination 9 had no demonstrable rubella specific antibodies while the remaining 3 had a low level of rubella specific antibodies, reacting only with the E1 protein. At one month after vaccination all the immunized subjects presented anti-E1, anti-E2, and anti-C specific antibodies. However, at 1-2 weeks after vaccination the 9 girls who were seronegative before immunization still had no detectable antibodies to any of the rubella virus structural proteins, while the 3 subjects whose preimmunization sera had reacted with the E1 protein presented an accelerated immune response, showing anti-E2 and anti-C specific antibodies and a more intensely marked anti-E1 specific band.