Cotransfection of ICAM-1 and HLA-DR reconstitutes human antigen-presenting cell function in mouse L cells.
The initiation of a specific immune response is believed to require not only activation through antigen-specific receptors on T cells and B cells but also antigen-independent interactions between accessory molecules. One such molecule is LFA-1, which enhances the avidity of interactions between T cells and antigen-presenting cells, and is possibly involved in signal transduction across the T-cell membrane. Intercellular adhesion molecule-1 (ICAM-1), a surface glycoprotein of relative molecular mass (Mr) 80,000-110,000, has been defined as a ligand for LFA-1, and has been shown to participate in the interaction between T cells and monocytes. The determination of the precise contribution of such accessory molecules to antigen presentation, however, is complicated by the need to analyse against a background of multiple molecular interactions. We have investigated the role of LFA-1/ICAM-1 interactions in antigen presentation directly by quantifying the contribution of ICAM-1 expression to T-cell stimulation using L-cell transfectants that co-express ICAM-1 and HLA-DR. In the case of transfectants expressing modest levels of HLA-DR, co-expression of ICAM-1 is critical for effective HLA class II-restricted and allospecific T-cell activation, pointing to an important role for ICAM-1 in the induction of T-cell responses.
Altmann
D M
DM
Human Immunogenetics Laboratory, Imperial Cancer Research Fund, London, UK.
Hogg
N
N
Trowsdale
J
J
Wilkinson
D
D
D000818:Animals; D000954:Antigens, Surface / Q000276:immunology*; D015815:Cell Adhesion Molecules; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D006801:Humans; D007739:L Cells; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins / Q000276:immunology*; D051379:Mice; D013601:T-Lymphocytes / Q000276:immunology*; D014162:Transfection
D000954:Antigens, Surface; D015815:Cell Adhesion Molecules; D000949:Histocompatibility Antigens Class II; D008562:Membrane Glycoproteins