EFFECTS OF EXOGENOUS SEXUAL HORMONES ON THE VAGINAL MICROBIOTA AND IMMUNE CELLS IN MICE

DE GREGORIO PR; JUÁREZ TOMÁS MS; SALVA S, ; ALVAREZ S; NADER-MACÍAS MEF; SANTOS V

Puerto Madryn. Chubut

Congreso; XLVI Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular.; 2010

The effect of progesterone (P) and estradiol (E) on several organs of an experimental animal model was evaluated. 2-months-old female BALB/c mice were inoculated with (P) (day -5) or E (day -2) to induce and maintain the different stages of the estrous cycle. The samples taken on days 0, 2, 6 and 8 post-injection of hormones were blood, vaginal fluid (VF), vagina, spleen and bone marrow (BM). Most of the animals remained in diestrous-metaestrous stages until day 6 post-P-injection or in proestrous-estrous stages until day 8 post-E-injection. The numbers of enterobacteria, staphylococci and lactic acid bacteria in VF were higher in estrogenized animals. In VF, myeloid population (Gr-1+) was dominant compared to T (CD3+) and B (B220+) lymphoid populations, determined by flow cytometry. On days 0 and 2, the Gr-1+ cells of VF were higher in estrogenized mice. The hormonal treatments did not produce significant differences in the myeloid and T cell populations of BM or spleen. Only in spleen, a significant increase of mature B cells (B220HighCD24Low) and a decrease of immature B cells (B220LowCD24High) was observed in P-inoculated mice compared with E-inoculated. These results allow the selection of the most suitable experimental conditions to further evaluate the mechanisms of interaction between beneficial vaginal lactobacilli and the host in a murine experimental model.