title: Generation of T cell help through a MHC class I-restricted TCR.
abstract: CD4+ T cells that are activated by a MHC class II/peptide encounter can induce maturation of APCs and promote cytotoxic CD8+ T cell responses. Unfortunately, the number of well-defined tumor-specific CD4+ T cell epitopes that can be exploited for adoptive immunotherapy is limited. To determine whether Th cell responses can be generated by redirecting CD4+ T cells to MHC class I ligands, we have introduced MHC class I-restricted TCRs into postthymic murine CD4+ T cells and examined CD4+ T cell activation and helper function in vitro and in vivo. These experiments indicate that Ag-specific CD4+ T cell help can be induced by the engagement of MHC class I-restricted TCRs in peripheral CD4+ T cells but that it is highly dependent on the coreceptor function of the CD8beta-chain. The ability to generate Th cell immunity by infusion of MHC class I-restricted Th cells may prove useful for the induction of tumor-specific T cell immunity in cases where MHC class II-associated epitopes are lacking.
authors.affiliation: Division of Immunology, The Netherlands Cancer Institute, Plesmanlaan 121, CX 1066 Amsterdam, The Netherlands.
authors.forename: Helmut W H G
authors.initials: HW
authors.lastname: Kessels
authors.forename: Koen
authors.initials: K
authors.lastname: Schepers
authors.forename: Marly D
authors.initials: MD
authors.lastname: van den Boom
authors.forename: David J
authors.initials: DJ
authors.lastname: Topham
authors.forename: Ton N M
authors.initials: TN
authors.lastname: Schumacher
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology / Q000378:metabolism; D016827:CD8 Antigens / Q000502:physiology; D002454:Cell Differentiation / Q000276:immunology; D002460:Cell Line; D049109:Cell Proliferation; D019281:Dimerization; D015395:Histocompatibility Antigens Class I / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D007424:Intracellular Fluid / Q000276:immunology / Q000378:metabolism; D008024:Ligands; D008213:Lymphocyte Activation / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D011948:Receptors, Antigen, T-Cell / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D015398:Signal Transduction / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology* / Q000378:metabolism*
chemical_list: D016827:CD8 Antigens; C431698:CD8alpha antigen; C433839:CD8alphabeta antigen; C477867:CD8beta antigen; D015395:Histocompatibility Antigens Class I; D008024:Ligands; D011948:Receptors, Antigen, T-Cell