HLA EXPRESSION ON IMMATURE AND MATURE HUMAN GERM-CELLS

Human leukocyte antigens (HLA) are membrane-bound glycoproteins encode d by the human major histocompatibility complex located on chromosome 6. They are known to function in immunologic recognition and, with reg ard to reproduction, a number of non-immune functions have been propos ed. Although the expression patterns of the major histocompatibility a ntigens have been extensively studied at the maternal-fetal inter face , there are still controversial reports on the expression of these mol ecules by human gametes and preimplantation stages. This brief review focuses on recent studies where the expression and distribution of HLA on human spermatogenic cells (spermatogonia, primary and secondary sp ermatocytes, spermatids, spermatozoa), primary and secondary oocytes, and preimplantation embryos have been investigated. These results, and their possible implications for the fertilization process and further embryonic development. will be presented. (C) 1998 Elsevier Science I reland Ltd. All rights reserved.