Major Histocompatibility Complex Class I G (MHCG)

HLA-G differs from the other MHC class I genes by its low polymorphism and alternative splicing that generates seven HLA-G proteins, whose tissue-distribution is restricted to normal fetal and adult tissues that display a tolerogeneic function toward both innate and acquired immune cells. Soluble HLA-G is an immunosuppressive molecule inducing apoptosis of activated CD8 T cells and down-modulating CD4 T cell proliferation. Monitoring of sHLA-G in amniotic fluid and plasma of pregnant women may have an important prognostic value to recognize pathological situations.

In addition, soluble HLA-G plasma levels are increased in lyphoproliferative disorders or in patients suffering from malignant melanoma, glioma, breast and ovarian cancer.HLA-G belongs to the HLA nonclassical class I heavy chain paralogues.