Regulation of reproductive tract immunoglobulins by oestradiol-17β in the European Red Fox (Vulpes vulpes)

Abstract

The effect of the ovarian hormone, oestradiol-17β, on reproductive tract immunity in the female fox was investigated. Reproductive tract antibody responses were induced by either Peyer’s patch immunization with a recombinant fox sperm protein, or by oral immunization with live, attenuated Salmonella typhimurium. The effect of exogenous oestradiol-17β or the stage of the oestrous cycle on reproductive tract immunity was assessed. The secretion of specific vaginal IgA, but not vaginal IgG, antibodies was reduced by exogenous treatment with oestradiol-17β, while both specific vaginal IgA and vaginal IgG levels declined during the period of natural oestrus. It is concluded that oestradiol-17β, and probably other reproductive hormones, are involved in the regulation of antibody-secretion in the fox reproductive tract, and that reproductive status is an important factor to consider in the design and application of vaccines which aim to induce immunity within the female reproductive tract.