Cell-mediated and antibody immune responses to AIK-C and Connaught monovalent measles vaccine given to 6 month old infants

Measles vaccination of infants younger than 1 year of age should be success ful in populations with a high proportion of measles vaccinated mothers. In fants whose mothers were vaccinated are born with less maternal antibody wh ich can interfere with vaccination compared with infants whose mothers had measles. AIK-C or Connaught (CLL) measles vaccine was given to 300 6 month infants born to mothers who had measles (group 1) or who were vaccinated ag ainst measles (group 2). Pre- and post-vaccination measles antibody was mea sured by EIA and PRN and cell mediated immunity (CMI) by blast transformati on and production of interferon-gamma and interleukin-10. After vaccination , mean antibody level, seroconversion and blastogenesis were significantly lower for group 1 than group 2 (p < 0.05). Post-vaccination measles Ige was significantly higher for group 2 CLL vaccinees compared with group 2 AIK-C (p < 0.05); seroconversion rates were 73 and 63%, respectively. More than 93% of group 2 infants had elevated measles IgG after vaccination. About 89 % of all children had some evidence of a blastogenic response. Lymphoprolif eration correlated strongly with cytokine production and weakly with IgG. N ot all seroresponders had a CMI response and vice versa. AIK-C and CLL vacc ines induce strong measles specific T and B immunity in most 6 month infant s of vaccinated mothers. (C) 1999 Elsevier Science Ltd. All rights reserved .