The expression of major histocompatibility complex class I in endometrial epithelial cells from dairy cow under a simulating hypoxic environment.

During the first trimester of pregnancy in dairy cows, the fetus is mainly recognized by the expression of major histocompatibility complex class I (MHC-I) in the maternal immune system. Before the embryo begins to implant in the maternal uterus, it requires a long time to remodel and develop vessels in the placenta. During this stage, the embryos are exposed to a hypoxic environment. However, the expression of bovine MHC-I has not been determined in hypoxic bovine endometrial epithelial cells (bEECs). Hypoxia-inducible factor-1α (HIF-1α) is a marker for hypoxic conditions in cells. In the present study, we used cobalt chloride (CoCl2 ) to establish a hypoxic cell model and then determined the expression of the classical gene BoLA-A and the non-classical gene MICB. qRT-PCR and western blot assays were applied to determine the expression of HIF-1α. qRT-PCR was performed to detect the levels of BoLA-A and MICB mRNAs. The results showed that HIF-1α expression was increased in the hypoxic cell model. The expression of BoLA-A was increased, but MICB levels were decreased in bEECs. Our study provides a basis for exploring the cattle intrauterine environment during pregnancy.