title: Investigation of peptide involvement in T cell allorecognition using recombinant HLA class I multimers.
abstract: Alloreactive T cells are involved in injurious graft rejection and graft-vs-host disease. However, they can also evoke beneficial responses to tumor Ags restricted by foreign MHC molecules. Manipulation of these alloreactivities requires information on the basis of T cell allorecognition. The vigorous T cell response to foreign MHC molecules may arise from peptide-independent recognition of polymorphic residues of foreign MHC molecules or peptide-specific recognition of novel peptides presented by foreign MHC molecules. We investigated CD8+ T cell allorecognition using recombinant HLA class I/peptide complexes. Peptide-specific allorecognition was examined using tetramers of HLA-A*0201 representing five peptides derived from ubiquitously expressed self-proteins that are known to bind endogenously to HLA-A*0201. Distinct subsets of CD8+ T cells specific for each HLA-A*0201/peptide combination were detected within four in vitro-stimulated T cell populations specific for foreign HLA-A*0201. Peptide-independent allorecognition was investigated using artificial Ag-presenting constructs (aAPCs) coated with CD54, CD80, and functional densities of a single HLA-A*0201/peptide combination for four different peptides. None of the four T cell populations specific for foreign HLA-A*0201 were stimulated by the aAPCs, whereas they did produce IFN-gamma upon stimulation with cells naturally expressing HLA-A*0201. Thus, aAPCs did not stimulate putative peptide-independent allorestricted T cells. The results show that these alloreactive populations comprise subsets of T cells, each specific for a self-peptide presented by foreign class I molecules, with no evidence of peptide-independent components.
authors: The Anthony Nolan Research Institute, Royal Free Hospital, Hampstead, London, United Kingdom.
authors: Alison M E
authors: AM
authors: Whitelegg
authors: Liesbeth E M
authors: LE
authors: Oosten
authors: Susan
authors: S
authors: Jordan
authors: Michel
authors: M
authors: Kester
authors: Astrid G S
authors: AG
authors: van Halteren
authors: J Alejandro
authors: JA
authors: Madrigal
authors: Els
authors: E
authors: Goulmy
authors: Linda D
authors: LD
authors: Barber
mesh_terms: D017951:Antigen Presentation / Q000235:genetics; D000938:Antigen-Presenting Cells / Q000276:immunology / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D002460:Cell Line; D002461:Cell Line, Transformed; D018984:Epitopes, T-Lymphocyte / Q000276:immunology* / Q000378:metabolism; D015234:HLA-A Antigens / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D015789:HLA-A2 Antigen; D015235:HLA-B Antigens / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D015793:HLA-B7 Antigen; D007371:Interferon-gamma / Q000096:biosynthesis; D007519:Isoantigens / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D008213:Lymphocyte Activation / Q000235:genetics; D010446:Peptide Fragments / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D011485:Protein Binding / Q000235:genetics / Q000276:immunology; D011994:Recombinant Proteins / Q000276:immunology* / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism
chemical_list: D018984:Epitopes, T-Lymphocyte; D015234:HLA-A Antigens; C435939:HLA-A*02:01 antigen; D015789:HLA-A2 Antigen; D015235:HLA-B Antigens; C477444:HLA-B*07:02 antigen; D015793:HLA-B7 Antigen; D007519:Isoantigens; D010446:Peptide Fragments; D011994:Recombinant Proteins; D007371:Interferon-gamma