Early pregnancy modulates the expression of interferon-stimulated genes, progesterone receptors, and progesterone-induced blocking factor in ovine duodenum

In ruminants, the signal (interferon-tau, IFNT) for the maternal recognition of pregnancy has effects on maternal extrauterine organs, and progesterone plays a key role during pregnancy. However, it is unclear that early pregnancy has effects on the expression of interferon-stimulated genes (ISGs), progesterone receptors (PGRs), and progesterone-induced blocking factor (PIBF) in ovine small intestine. In this study, small intestines were obtained at day 16 of the estrous cycle, days 13, 16, and 25 of pregnancy, and RT-qPCR assay, Western blot, and immunohistochemistry were used to analyze the effects of early pregnancy on the expression of ISGs, PGR, and PIBF in the small intestine. The results indicated that expression levels of ISG15-conjugated protein, signal transducer and activator of transcription 1 (STAT1), myxovirus resistance protein 1, and interferon-gamma-inducible protein 10 (IP-10) at day 13 of pregnancy were the lowest. However, expression levels of PGR isoforms (60 kDa and 40 kDa), PIBF, STAT1 and 2′,5′-oligoadenylate synthetase 1 upregulated, but the expression value of IP-10 downregulated at day 25 of pregnancy compared with day 16 of the estrous cycle. In conclusion, early pregnancy modulated the expression of ISGs, PGR, and PIBF in ovine duodenum, which was implicated in immunoregulation and nutrient absorption of the small intestine in ewes.