HLA-G, pre-eclampsia, immunity and vascular events

J Reprod Immunol. 2003 Aug;59(2):219-34. doi: 10.1016/s0165-0378(03)00049-4.

Abstract

Pre-eclampsia, one of the main complications in pregnancy, is characterised by shallow cytotrophoblast invasion of decidua as well as by vascular endothelial cell dysfunction, leading to a poor perfusion of placenta. A striking feature of pre-eclamptic pregnancies is that expression of HLA-G protein is reduced in term placentas compared with normal pregnancy. How such HLA-G deficient expression may be related to the pre-eclamptic pathology is unknown. Here, we review the major structural characteristics of HLA-G and some of its functions that have been recently characterised. Soluble HLA-G1 isoform down-regulates both CD8(+) and CD4(+) T cell reactivity. HLA-G also modulates innate immunity by binding to several NK and/or decidual receptors, inducing particular cytokine secretion. HLA-G was shown to be less susceptible to human cytomegalovirus-derived US protein down-modulation. Finally, soluble HLA-G1 down-regulates endothelial cell proliferation and migration. In view of these different HLA-G properties, we will briefly discuss how defective HLA-G function may contribute to the low trophoblast invasion and vascular abnormalities observed in pre-eclamptic placentas.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis
  • CD4-Positive T-Lymphocytes / immunology
  • CD8-Positive T-Lymphocytes / immunology
  • Cell Movement
  • Cytomegalovirus / physiology
  • Down-Regulation
  • Endothelium, Vascular / physiology*
  • Female
  • HLA Antigens / physiology*
  • HLA-G Antigens
  • Histocompatibility Antigens Class I / physiology*
  • Humans
  • Immunity, Innate
  • Killer Cells, Natural / immunology
  • Mice
  • Placenta / immunology*
  • Placenta / metabolism
  • Pre-Eclampsia / immunology*
  • Pre-Eclampsia / metabolism
  • Pregnancy
  • Trophoblasts / immunology
  • Trophoblasts / physiology*

Substances

  • HLA Antigens
  • HLA-G Antigens
  • Histocompatibility Antigens Class I