earticle

영어

Type 1 regulatory T (Tr1) cell is identified as a subset of regulatory CD4+ T cells which have unique Fox3- phenotype and are differed from the classical Treg cell. These Tr1 cells play an important role in immune suppressive function by secreting the anti-inflammatory cytokine interleukin 10 (IL10). In humans and mice, lymphocyte activation gene 3 (LAG3) and integrin subunit alpha 2 (ITGA2) are used to identify Tr1 cells. Differentiation of Tr1 cell and their IL10 production are facilitated by interleukin 27 (IL27), which can activate transcription factors such as c-Maf and Ahr. However, the expression of Trl cell maker genes, IL27, and IL10 in the uterine endometrium during pregnancy have not been well studied in pigs. Thus, we determined expression of Trl cell makers, LAG3 and CD49, IL27, and IL10 in the uterine endometrium during the estrous cycle and pregnancy in pigs. We obtained endometrial tissues from gilts on day (D) 12 and D15 of the estrous cycle and D12, D15, D30, D60, D90, and D114 of pregnancy. Real time RT-PCR analysis showed that levels of Trl cell makers, LAG3 and ITGA2, mRNAs changed in the uterine endometrium during pregnancy. Especially, levels of LAG3 mRNA on D15 of pregnancy were higher than those on D15 of the estrous cycle. Also, IL27 and IL10 mRNAs expressed in the uterine endometrium during the estrous cycle and pregnancy in a pregnancy stage-specific manner. Levels of IL27 and IL10 mRNAs in the uterine endometrium were highest on D15 of pregnancy and decreased toward term pregnancy. Immunohistochemistry showed that IL10 protein was localized specifically to scattered cell types in stroma during pregnancy. Abundance of IL27 mRNAs, but not LAG3, in the uterine endometrium was increased by the treatment of IFNG. These results showed that Trl cell makers, LAG3 and ITGA2, IL27, and IL10 were expressed in the uterine endometrium and IFNG increased endometrial IL27 expression in pigs, suggesting that Trl cell may play a key role in the establishment and maintenance of pregnancy by regulating the endometrial immune environment via anti-inflammatory cytokine, IL10, in pigs.