Effect of progesterone on the vaccination and immune response against Chlamydia abortus in sheep

Publication date: Available online 27 June 2019Source: Veterinary Immunology and ImmunopathologyAuthor(s): A. Murcia-Belmonte, D. Álvarez, N. Ortega, J.A. Navarro, E. Gómez-Lucía, A.J. Buendía, J. Sánchez, L. del Río, J. Salinas, M.R. CaroAbstractChlamydia abortus produces ovine enzootic abortion (OEA). Symptoms are not observed until the organism colonises the placenta, eventually causing abortion. Infected animals become carriers and will shed the organism in the following oestruses. This process suggests that sex hormones might play an important role in the physiopathology of OEA, affecting the success of chlamydial clearance and also jeopardising the effectiveness of vaccination. However, the mechanisms through which sex hormones are involved in chlamydial pathogenicity remain unclear. The aim of this study, therefore, was to determine the effect of progesterone on the immune response against C. abortus and on the protection conferred by an experimental inactivated vaccine in sheep.Eighteen sheep were ovariectomised and divided into four groups: vaccinated and progesterone-treated (V-PG), vaccinated and non-treated (V-NT), non-vaccinated and non-treated (NV-NT) and non-vaccinated and progesterone-treated sheep (NV-PG). Animals from both PG groups were treated with commercial medroxyprogesterone acetate impregnated intravaginal sponges before and during the vaccination (V-PG) or just before challenge (NV-PG). The animals from both V groups were subcutaneously immunis...
Source: Veterinary Immunology and Immunopathology - Category: Veterinary Research Source Type: research