earticle

영어

For the successful pregnancy maternal immune response must be regulated to tolerate the semi-allogenic conceptus. In adaptive immunity, major histocompatibility complex class II (MHC class Ⅱ) molecules play critical role in presenting foreign antigens to the other immune cells. During early pregnancy in pigs, various types of endometrial cells, including epithelial cells, vascular endothelial cells, stromal cells, and infiltrated immune cells are activated by conceptus-derived interferon gamma (IFNG) and express immune regulatory molecules. Therefore, we determined the expression and regulation of MHC class II molecules, swine leukocyte antigen (SLA) -DM, -DO, -DR and -DQ and their transcription coactivator CIITA at the maternal-conceptus interface. We obtained endometrial tissue samples from day (D) 12 and D15 of the estrous cycle and D12, D15, D30, D60, D90 and D114 of pregnancy. Quantitative real-time PCR anaysis showed that mRNA levels of all genes dramatically increased on D15 of pregnancy. To determine the effect of interferon-gamma (IFNG) on SLAs and CIITA expression, we took advantage of explant culture and found that all of SLAs and CIITA were up-regulated by IFNG in a dose-dependent manner. Immunohistochemistry showed that CIITA protein was localized to vascular endothelial cells and stroma near the luminal epithelium on D15 of pregnancy. SLA-DQ protein is localized to stromal leukocytes and vascular endothelial cells during the estrous cycle and early pregnancy with the highest signal intensity on D15 of pregnancy. These results indicate that CIITA and MHC class II molecules are expressed in the uterine endometrium in a cell-type and stage-specific fashion during pregnancy, and may play a critical role in regulation of maternal immune response to support the establishment and maintenance of pregnancy at the maternal- conceptus interface in pigs.