ausblenden:
Schlagwörter:
Tap1; Human trophoblast; Hla-g; Major; Histocompatibility complex class i.; Early-pregnancy decidua; Large granular lymphocytes; Choriocarcinoma cell-line; Class-i molecules; Complex class-i; Monoclonal-antibodies; Insitu hybridization; Chorionic villi; Messenger-rna.; Immunology.
Zusammenfassung:
Successful placentation in the human is dependent on the trophoblast evading recognition and destruction by the maternal immune system. However, invasive cytotrophoblast express HLA-G which may be able to present peptide to T cells. Transporter proteins are essential for peptide presentation and major histocompatibility complex (MHC) class I assembly. We have determined their expression by trophoblast in relation to HLA-G, using immunohistochemistry. Antitransporter protein antibody (TAP1) labeling closely paralleled that of MHC class I, but the intensity of its expression was much greater on the HLA-G(+) extravillous cytotrophoblast than any other fetal or maternal tissue in the first trimester and at term. This suggests that the extravillous cytotrophoblast are very actively assembling MHC class I antigens with peptides. However, expression of MHC class I by the cytotrophoblast was not correspondingly elevated. This pattern could result from HLA-G being shed from the surface of the trophoblast, a process which may play a central role in protecting the fetus from maternal immune attack. [References: 36]