title: Antigen processing and presentation by human trophoblast-derived cell lines.
abstract: The trophoblast-derived choriocarcinoma cell lines JEG-3 and JAR express the nonclassical MHC class I molecules HLA-G (JEG-3) or, at a low level, HLA-E (JAR), but lack expression of the classical MHC class I molecules HLA-A and HLA-B. Expression of these nonclassical MHC class I genes was found to coincide with expression of the genes encoding the peptide transporter associated with Ag processing (TAP). In immunoprecipitation studies, a physical interaction between the TAP complex and HLA-G or HLA-E could be demonstrated. To investigate whether trophoblast-derived cell lines were capable of peptide processing, transport, and loading of MHC class I molecules, HLA-A*0201-expressing transfectants of JEG-3 and JAR were used for functional studies. These transfectants were recognized by both allospecific cytotoxic T cell clones and, after viral infection, by an influenza A matrix peptide-specific cytotoxic T cell clone, indicating that these trophoblast-derived cell lines were capable of presenting endogenously derived peptides in the context of HLA-A*0201. From these observations, it can be inferred that the TAP complex and other molecules involved in Ag processing and presentation by MHC class I molecules are functionally active in these trophoblast-derived cell lines. This implies that trophoblasts are able to provide antigenic peptides for presentation by nonclassical MHC class I molecules that are naturally expressed by this cell type.
authors.affiliation: Department of Immunohaematology and Blood Bank, Leiden University Hospital, The Netherlands.
authors.forename: S J
authors.initials: SJ
authors.lastname: Gobin
authors.forename: L
authors.initials: L
authors.lastname: Wilson
authors.forename: V
authors.initials: V
authors.lastname: Keijsers
authors.forename: P J
authors.initials: PJ
authors.lastname: Van den Elsen
mesh_terms: D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters / Q000276:immunology; D017951:Antigen Presentation; D005260:Female; D006680:HLA Antigens / Q000276:immunology*; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000276:immunology*; D006801:Humans; D011247:Pregnancy; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology / Q000473:pathology; D014327:Trophoblasts / Q000276:immunology* / Q000473:pathology; D014407:Tumor Cells, Cultured; D000097625:HLA-E Antigens
chemical_list: D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters; D006680:HLA Antigens; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I; D000097625:HLA-E Antigens; C073119:TAP1 protein, human; C071692:TAP2 protein, human