Biochemical and functional association between CD8 and H-2 at the surface of a T cell clone.
In an attempt to define structures interacting with CD8 molecules during activation of CD8+ cells, immunoprecipitates of CD8 and Tcr-CD3 molecules from lysates of a surface-labeled CTL clone were analyzed. No proteins other than the known Tcr alpha/beta and associated CD3 components were detected in either anti-Tcr or anti-CD3 immunoprecipitates, whether or not the CTL clone had been activated. However, anti-CD8 antibodies co-precipitated class I MHC heavy chain and associated beta 2-microglobulin in all conditions. The latter co-precipitation was shown to result from "cis-type" interactions between CD8 and class I MHC proteins on the same cell and to involve a degree of selectivity, as class I MHC molecules were absent from immunoprecipitates of highly expressed cell surface molecules such as LFA-1. A further analysis of cell surface molecular distribution during antigen-dependent CTL-target cell interaction by double fluorescence-microscopy in non-activating conditions indicated that an increased density of CTL class I molecules was found in the CTL-target cell contact zone of most conjugates with redistributed CD8 molecules. A possible role for "cis-type" class I MHC-CD8 interactions in the dynamics of CTL-target cell contacts is proposed.
Centre d'Immunologie INSERM-CNRS de Marseille-Luminy, France.
N
N
Auphan
C
C
Boyer
P
P
Andre
P
P
Bongrand
A M
AM
Schmitt-Verhulst
D000818:Animals; D015703:Antigens, CD / Q000032:analysis; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology*; D000954:Antigens, Surface / Q000032:analysis; D017252:CD3 Complex; D016827:CD8 Antigens; D002999:Clone Cells; D004591:Electrophoresis, Polyacrylamide Gel; D006183:H-2 Antigens / Q000276:immunology*; D006649:Histocompatibility Antigens / Q000032:analysis; D066298:In Vitro Techniques; D015759:Ionomycin / Q000494:pharmacology; D017493:Leukocyte Common Antigens; D008213:Lymphocyte Activation; D016169:Lymphocyte Function-Associated Antigen-1 / Q000032:analysis; D051379:Mice; D008856:Microscopy, Fluorescence; D011948:Receptors, Antigen, T-Cell / Q000032:analysis / Q000276:immunology; D016693:Receptors, Antigen, T-Cell, alpha-beta; D015375:Receptors, Interleukin-2 / Q000032:analysis; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D018800:Thy-1 Antigens
D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D017252:CD3 Complex; D016827:CD8 Antigens; D006183:H-2 Antigens; C024755:H-2K(K) antigen; D006649:Histocompatibility Antigens; D016169:Lymphocyte Function-Associated Antigen-1; D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta; D015375:Receptors, Interleukin-2; D018800:Thy-1 Antigens; D015759:Ionomycin; D017493:Leukocyte Common Antigens; D013755:Tetradecanoylphorbol Acetate