title: Self-nonself discrimination and repertoire selection of human T cells differentiated in an HLA-semiallogeneic environment following bone marrow transplantation for severe combined immunodeficiency.
abstract: We have analyzed allorecognition, HLA restriction and T cell receptor (TcR) diversity in an HLA-heterozygous (HLA-DRw6,7) severe combined immunodeficiency (SCID) patient whose T cell system had been repopulated by HLA-homozygous (HLA-DRw6) paternal T cells following T cell-depleted bone marrow transplantation (BMT). Donor origin of T cells and host origin of antigen-presenting cells (APC) in peripheral blood and BM is shown by HLA typing of separated cell populations and two-color immunofluorescence using an anti-HLA monoclonal antibody (mAb). Peripheral blood lymphocytes (PBL) from the chimeric patient proliferate normally against PHA, anti-TcR/CD3 mAb, pooled allogeneic PBL, and also against the recall antigen (Ag) tetanus toxoid and purified protein derivative of tuberculin (PPD) following immunization, suggesting recognition by donor (DRw6) T cells of Ag presented by host (DRw6,7) APC. PPD-specific cytotoxic T lymphocytes generated in vitro from patient PBL post-BMT display specific cytotoxicity against targets expressing DRw6 and DR7, but not against DR-mismatched targets, suggesting that HLA restriction of Ag recognition may occur through determinants expressed by the host and not by the donor. Donor T cells differentiated in the HLA-semiallogeneic host show specific proliferative and cytotoxic responses against HLA-mismatched stimulators, but not against stimulators taken from the host, expressing the host-specific HLA-haplotype, or expressing the host-specific HLA-DR7 antigens. Compared to T cells directly taken from the donor, differentiation of donor T cells in the host is associated with a significant decrease of T cells expressing TcR V beta 5 and V alpha 2 determinants, while no differences in the abundance of of TcR V beta 6, V beta 8 and V beta 12 subsets were noticed. We conclude that allorecognition, major histocompatibility complex (MHC) restriction and TcR diversity generation of human T cells can be modulated through differentiation in an MHC-different environment, as had been previously shown to be the case in murine model systems.
authors.affiliation: Department of Pediatrics II, University Ulm, FRG.
authors.forename: C
authors.initials: C
authors.lastname: Knobloch
authors.forename: S F
authors.initials: SF
authors.lastname: Goldmann
authors.forename: W
authors.initials: W
authors.lastname: Friedrich
mesh_terms: D000938:Antigen-Presenting Cells / Q000276:immunology; D001324:Autoantigens / Q000276:immunology; D016026:Bone Marrow Transplantation / Q000276:immunology*; D002454:Cell Differentiation; D003602:Cytotoxicity, Immunologic; D006680:HLA Antigens / Q000276:immunology*; D006239:Haplotypes; D006801:Humans; D007111:Immunity, Cellular; D008212:Lymphocyte Depletion; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000276:immunology; D016511:Severe Combined Immunodeficiency / Q000276:immunology* / Q000601:surgery; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology
chemical_list: D001324:Autoantigens; D006680:HLA Antigens; D016693:Receptors, Antigen, T-Cell, alpha-beta