Ureaplasma diversum infection in vitro alters prostaglandin E₂ and prostaglandin F(2a) production by bovine endometrial cells without affecting cell viability

Bovine epithelial and stromal cells of the endometrium were inoculated with Ureaplasma diversum, pathogenic strain 2312, at 10⁶ or 10³ color- changing units (ccu)/ml in the presence of 1% fetal bovine serum (depleted of steroids by dextran-charcoal treatment) to assess the effect of infection on prostaglandin biosynthesis. When the inoculum of U. diversum was 10⁶ ccu/ml, the concentration of U. diversum in the culture medium decreased with time. U. diversum was found on the epithelial and stromal cell monolayers, increasing in titer 100-fold, indicating that attachment and eventually growth occurred. When the inoculum was 10³ ccu/ml, the titer of U. diversum remained the same or increased in the supernatant and increased on epithelial and stromal cells. The effect of infection was evaluated by measurement of the primary prostaglandin produced by each cell type, prostaglandin F(2a) for epithelial cells and prostaglandin E₂ for stromal cells. Infection with U. diversum significantly decreased prostaglandin F(2a) accumulation, by 44.7% ± 6.0% at 10⁶ ccu/ml (P ≤ 0.005) and 15.8% ± 5.3% at 10³ ccu/ml (P ≤ 0.05) in epithelial cells. Prostaglandin E₂ accumulation by stromal cells was decreased by 34.0% ± 4.0% at 10⁶ ccu/ml (P ≤ 0.001) and by 13.5% ± 2.7% at 10³ ccu/ml (P ≤ 0.005). Infection with 10⁶ ccu/ml did not alter endometrial cell viability, as shown by protein measurement, trypan blue dye exclusion, and cell plating efficiency tests. Thus, alterations in prostaglandin production were not due to cell deterioration. These observations suggest that U. diversum can alter prostaglandin E₂ and prostaglandin F(2a) patterns in primary cultures of bovine endometrial cells without affecting cell viability.