Immunogenicity of a recombinant chimeric antigen using Aβ1-15 epitope fused to a T helper epitope / 军事医学

ABSTRACT

Objective To explore the immunogenicity of recombinant chimeric 6Aβ15-T including the Aβ1-15 epitope and a T-helper epitope formulated with different adjuvants and to evaluate its feasibility as a candidate vaccine for Alzheimer disease (AD).Methods The recombinant chimeric antigen 6Aβ15-T formulated with Al adjuvant, Freund′s adjuvant or MF59 adjuvant was administered to two strains of mice .The 6Aβ15-T-immunized group without adjuvants ( Mock) and non-immunized group (Control) were included in this study as control groups .The specific antibody and cellular immune response of the chimeric antigen were evaluated .Results In BALB/c strain mice, three types of adjuvants could substan-tially boost the immunogenicity of chimeric antigen 6Aβ15-T and produce a high level of specific-Aβ(β-amyloid) antibod-ies.In C57BL/6 strain mice, the existence of adjuvants enhanced the immune response of 6Aβ15-T antigen, but the mice in Mock group also produced a strong antibody response .In two strains of mice, prevalence of anti-AβIgG1, which was an indicator of Th2 polarization, was observed in the 6Aβ15-T-immunized mice.Additionally, the Al adjuvant induced a high-er level of IgG1 antibody titers, and the ratio of IgG1/IgG2a was the largest.As expected, the 6Aβ15-T antigen formulated with or without adjuvants induced PADRE-specific, but not Aβ42-specific T cellular immune response .Conclusion The 6Aβ15-T antigens formulated with different types of adjuvants could induce strong Th 2-polarized Aβ42-specific antibody re-sponses without activating self-reactive Aβ42-specific T cells in two strains of mice .The results suggested that the recombi-nant chimeric antigen 6Aβ15-T is a good candidate vaccine for AD .