Objective:To evaluate physicochemical and immune efficacy of filamentous hemagglutinin(FHA)and pertactin(PRN)before and after detoxification treatment in acellular pertussis vaccine.Methods:Thermal stability of FHA and PRN was analyzed by differential scanning fluorescence(DSF)to evaluate melting temperature(Tm)changes of antigen before and after detoxi-fication treatment.Immune efficacy of vaccine containing single FHA or PRN component and acellular pertussis vaccine with pertussis toxin(PT)was assessed by modified intracerebral challenge assay(MICA)and pertussis serological potency test(PSPT).ELISpot and flow cytometry were utilized to evaluate cytokines secretion and immune cells level in spleens obtained from immunized mice.Results:Under detoxification treatment Tm of FHA changed from a single value 57℃to both 58℃and 81℃,but Tm of PRN were both 84℃.Detoxification treatment had no obvious effects on immune efficacy and IL-4/IFN-γ secretion in spleens from mice.In addi-tion,there was no significant difference in splenic immune cells such as CD4+T,CD8+T and CD44+CD62L+memory cells.Conclu-sion:Detoxification treatment of FHA and PRN have no effect on immune efficacy of acellular pertussis vaccine,except for impact on Tm of FHA.

Objective:To evaluate physicochemical and immune efficacy of filamentous hemagglutinin(FHA)and pertactin(PRN)before and after detoxification treatment in acellular pertussis vaccine.Methods:Thermal stability of FHA and PRN was analyzed by differential scanning fluorescence(DSF)to evaluate melting temperature(Tm)changes of antigen before and after detoxi-fication treatment.Immune efficacy of vaccine containing single FHA or PRN component and acellular pertussis vaccine with pertussis toxin(PT)was assessed by modified intracerebral challenge assay(MICA)and pertussis serological potency test(PSPT).ELISpot and flow cytometry were utilized to evaluate cytokines secretion and immune cells level in spleens obtained from immunized mice.Results:Under detoxification treatment Tm of FHA changed from a single value 57℃to both 58℃and 81℃,but Tm of PRN were both 84℃.Detoxification treatment had no obvious effects on immune efficacy and IL-4/IFN-γ secretion in spleens from mice.In addi-tion,there was no significant difference in splenic immune cells such as CD4+T,CD8+T and CD44+CD62L+memory cells.Conclu-sion:Detoxification treatment of FHA and PRN have no effect on immune efficacy of acellular pertussis vaccine,except for impact on Tm of FHA.