How Micrornas Affect the Expression of Human Leukocyte Antigeng in Pregnancy

The expression of Human Leukocyte Antigen G (HLA-G) on Fetal Extravillous Trophoblast (EVT) cells during pregnancy plays an important role in preventing the fetus from rejection by suppressing the maternal immune system. Decreased expression levels of HLA-G have already shown to be associated with several complications of pregnancy such as pre-eclampsia. However, it remains largely unknown how HLA-G gene expression is regulated with regard to its function and its complications. Polymorphisms and microRNAs affect HLA-G gene expression and the formation of isoforms. Interestingly, three microRNAs, miR-148a, miR-148b and miR-152, downregulate HLA-G expression with functional consequences. Since HLA-G expression levels are reduced in pre-eclampsia without a known cause, we hypothesize that these microRNAs are involved in the development of pre-eclampsia. This review discusses how microRNAs can affect HLA-G gene expression and its functions. Additionally, the role of microRNAs in the development of pre-eclampsia will be reviewed.