Dynamic analysis of antibodies induced by leptospiral vaccines / 中华微生物学和免疫学杂志

ABSTRACT

Objective@#To investigate the dynamic changes of antibodies induced by leptospiral vaccines.@*Methods@#Antigens for antibody detection were screened out. ELISA was used to analyze antibody responses induced at different time points after immunizing guinea pigs with different batches of leptospiral vaccines from different manufacturers. To investigate the relationship between antibody responses induced by leptospiral vaccines and their protective effects in animal model, guinea pigs were challenged with Leptospira after immunization.@*Results@#There was no significant antigen-antibody reaction between the LigA protein or Patoc Ⅰ antigen and the serum samples of guinea pigs immunized with leptospiral vaccines. Notable IgG and IgM antibody reactions were observed in all vaccination groups when using bacterial proteins from seven Leptospira reference strains which were used for the preparation of leptospiral vaccines as envelope antigens. Antigen-specific IgG antibodies peaked at 35 d after the last immunization, and the highest peak of antigen-specific IgM antibodies was reached 11 d after the last immunization. Results of the challenge test showed that non-diluted leptospiral vaccines induced significant IgG and IgM antibody reactions in guinea pigs as compared with those diluted three or nine times, showing good protective effects.@*Conclusions@#Analysis of the dynamic changes of antibodies induced by leptospiral vaccines revealed that there was correlation between the induced serum antibody responses and the protective effects. This study provided reference for further study on alternative methods for evaluating leptospiral vaccine potency.