The Many Faces of Human Leukocyte Antigen-G: Relevance to the Fate of Pregnancy

TY - JOUR

T1 - The Many Faces of Human Leukocyte Antigen-G

T2 - Relevance to the Fate of Pregnancy

AU - Dahl, Mette

AU - Djurisic, Snezana

AU - Hviid, Thomas Vauvert F

PY - 2014

Y1 - 2014

N2 - Pregnancy is an immunological paradox, where fetal antigens encoded by polymorphic genes inherited from the father do not provoke a maternal immune response. The fetus is not rejected as it would be theorized according to principles of tissue transplantation. A major contribution to fetal tolerance is the human leukocyte antigen (HLA)-G, a nonclassical HLA protein displaying limited polymorphism, restricted tissue distribution, and a unique alternative splice pattern. HLA-G is primarily expressed in placenta and plays multifaceted roles during pregnancy, both as a soluble and a membrane-bound molecule. Its immunomodulatory functions involve interactions with different immune cells and possibly regulation of cell migration during placental development. Recent findings include HLA-G contributions from the father and the fetus itself. Much effort has been put into clarifying the role of HLA-G during pregnancy and pregnancy complications, such as preeclampsia, recurrent spontaneous abortions, and subfertility or infertility. This review aims to clarify the multifunctional role of HLA-G in pregnancy-related disorders by focusing on genetic variation, differences in mRNA stability between HLA-G alleles, differences in HLA-G isoform expression, and possible differences in functional activity. Furthermore, we highlight important observations regarding HLA-G genetics and expression in preeclampsia that future research should address.

AB - Pregnancy is an immunological paradox, where fetal antigens encoded by polymorphic genes inherited from the father do not provoke a maternal immune response. The fetus is not rejected as it would be theorized according to principles of tissue transplantation. A major contribution to fetal tolerance is the human leukocyte antigen (HLA)-G, a nonclassical HLA protein displaying limited polymorphism, restricted tissue distribution, and a unique alternative splice pattern. HLA-G is primarily expressed in placenta and plays multifaceted roles during pregnancy, both as a soluble and a membrane-bound molecule. Its immunomodulatory functions involve interactions with different immune cells and possibly regulation of cell migration during placental development. Recent findings include HLA-G contributions from the father and the fetus itself. Much effort has been put into clarifying the role of HLA-G during pregnancy and pregnancy complications, such as preeclampsia, recurrent spontaneous abortions, and subfertility or infertility. This review aims to clarify the multifunctional role of HLA-G in pregnancy-related disorders by focusing on genetic variation, differences in mRNA stability between HLA-G alleles, differences in HLA-G isoform expression, and possible differences in functional activity. Furthermore, we highlight important observations regarding HLA-G genetics and expression in preeclampsia that future research should address.

KW - Alleles

KW - Alternative Splicing

KW - Cell Membrane

KW - Female

KW - Gene Expression Regulation

KW - HLA-G Antigens

KW - Humans

KW - Organ Specificity

KW - Polymorphism, Genetic

KW - Pre-Eclampsia

KW - Pregnancy

KW - Pregnancy Complications

KW - Pregnancy Outcome

KW - Protein Transport

U2 - 10.1155/2014/591489

DO - 10.1155/2014/591489

M3 - Review

C2 - 24741608

SN - 0257-277X

VL - 2014

SP - 1

EP - 11

JO - Immunologic Research

JF - Immunologic Research

M1 - 591489

ER -