A limited role for antibody in protective immunity induced by rCPAF and CpG vaccination against primary genital Chlamydia muridarum challenge

Mice deficient in B cells (μmT mice) were used to evaluate the role of antibody in enhanced chlamydial clearance and reduction of pathology afforded by vaccination with recombinant chlamydial protease-like activity factor (rCPAF). Enhanced, but comparable, chlamydial clearance was observed in μmT and wild-type (WT) mice after rCPAF+CpG vaccination. Chlamydia-induced pathology was present in mock-immunized animals, but at significantly greater levels in μmT than WT mice, whereas vaccinated μmT and WT mice exhibited similar reductions in pathology. Thus, antibodies may play a role in protection against chlamydial pathology after primary infection, but were largely dispensable in rCPAF+CpG-induced chlamydial clearance and reduction in pathology.