title: Acquisition of HLA-DR and costimulatory molecules by T cells from allogeneic antigen presenting cells.
abstract: There is accumulating evidence that cell surface molecules may be transferred between cells during an encounter. The aim of these experiments was to determine whether transfer of allogeneic material to T cells could influence human alloresponses. CD4(+) cells were cocultured with M1 cell (human fibroblast) transfectants expressing HLA-DR1, CD80 and CD86 alone or in combination. Up to 95% of the allogeneic T cells became positive for HLA-DR and the appropriate costimulatory molecules after only 4 h of coculture. The phenomenon required cell contact and cell membrane fluidity because transfer was abolished by transwell separation of the M1 cells and the T cells or by pre-treatment of the APC with paraformaldehyde. Flow cytometric sorting of T cells after coculture and subsequent mixed lymphocyte assays demonstrated that the T cells that had acquired both HLA-DR and costimulatory molecules could act as potent antigen presenting cells. Finally, matured human dendritic cells were also shown to transfer these molecules to CD4(+) cells, which could then act as antigen presenting cells for unprimed T cells and for a cell line specific for an HLA-peptide complex acquired from the DCs. Taken together, these data suggest a novel pathway for the amplification of human alloresponses.
authors.affiliation: Department of Immunology, Faculty of Medicine, Imperial College, Hammersmith Hospital, Du Cane Road, London W12 0NN, UK.
authors.forename: David S
authors.initials: DS
authors.lastname: Game
authors.forename: Nicola J
authors.initials: NJ
authors.lastname: Rogers
authors.forename: Robert I
authors.initials: RI
authors.lastname: Lechler
mesh_terms: D000906:Antibodies / Q000494:pharmacology; D000938:Antigen-Presenting Cells / Q000276:immunology*; D015703:Antigens, CD / Q000235:genetics / Q000276:immunology*; D018122:B7-1 Antigen / Q000235:genetics / Q000276:immunology*; D051940:B7-2 Antigen; D018968:CD58 Antigens / Q000276:immunology; D002478:Cells, Cultured; D018920:Coculture Techniques; D003713:Dendritic Cells / Q000276:immunology; D005347:Fibroblasts / Q000187:drug effects / Q000276:immunology; D005557:Formaldehyde / Q000494:pharmacology; D006684:HLA-DR Antigens / Q000235:genetics / Q000276:immunology*; D006801:Humans; D008562:Membrane Glycoproteins / Q000235:genetics / Q000276:immunology*; D011108:Polymers / Q000494:pharmacology; D013601:T-Lymphocytes / Q000276:immunology*; D014162:Transfection
chemical_list: D000906:Antibodies; D015703:Antigens, CD; D018122:B7-1 Antigen; D051940:B7-2 Antigen; D018968:CD58 Antigens; C497964:CD86 protein, human; D006684:HLA-DR Antigens; D008562:Membrane Glycoproteins; D011108:Polymers; D005557:Formaldehyde; C003043:paraform