Development and characterization of a simian virus 40 immortalized bovine endometrial stromal cell line

Abstract

In ruminants, interferon-τ (IFNτ) is the maternal recognition signal inhibiting prostaglandin (PG) F2α production by endometrial epithelial cells and stimulating interferon-stimulated genes in the stroma. Stromal cells mediate the action of progesterone on epithelial cells during pregnancy. Our working hypothesis is that IFNτ acts as a molecular switch that turns on PGE2 production in endometrial stromal cells while suppressing PGF2α production from epithelial cells. In this report we document immortalization and functional characterization of a bovine stromal cell line from the caruncular region of the endometrium [caruncular stromal cell (CSC)]. Primary stromal cells were immortalized by nucleofection with simian virus 40 large T antigen and integrase. The resulting cell line, CSC, expresses stromal cell-specific vimentin, estrogen, and progesterone receptors, and is amenable for transient transfection. Basal and stimulated production of PGE2 is higher than PGF2α and associated with cyclooxygenase (COX) 2 expression. Phorbol myristate acetate (PMA) and IFNτ up-regulate COX2 and PG production in a dose-dependent manner. When added together, low concentrations of IFNτ inhibit PMA-induced COX2 expression; whereas this inhibition is lost at high concentrations. Expression of signal transducer and activator of transcription 1 is induced by IFNτ at all concentrations studied but is not modulated by PMA. Because expression of signal transducer and activator of transcription 1 does not exhibit the biphasic response to IFNτ, we investigated the p38 MAPK pathway using the selective inhibitor SB203580. Inhibition of the p38 MAPK pathway abolishes IFNτ action on PG production. In summary, CSC appears as a good stromal cell model for investigating the molecular mechanisms related to IFNτaction and PG production in the bovine. Copyright © 2009.