Immunogenicity of B[a]P-peptide conjugates after tetanus toxoid pre-vaccination.

<p>(A) Endpoint titers (serum dilution reaching 5 times the background) for TT specific IgG antibodies determined by indirect ELISA for sera pre-immunised with tetanus toxoid (TT) followed by B[a]P-peptide or B[a]P-TT conjugate vaccination. (B) B[a]P specific IgG antibodies with and without pre-vaccination. Results are presented for each mouse (○) and median value (–). There was no statistical significant difference between animal with and without pre-vaccination (One way ANOVA procedure followed by Student-Newman-Keuls-t test). (C, D) Antibody selectivity determined by competitive ELISA in sera immunised with B[a]P peptide or B[a]P-TT conjugates with (○) and without (•) tetanus toxoid (TT) pre-vaccination. B[a]P (C) and 7,8-diol-B[a]P (D) were used as competitors to compete for binding of specific antibodies to B[a]P-ovalbumin as the coated antigen. The IC₅₀ (concentration of competitor for 50% inhibition) was calculated to determine the antibody specificity for each tested competitor. The IC₅₀ is inverse correlated to the antibody affinity. Results are presented for each mouse (circle) and median value (–).