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Publié dans: Mol Immunol 1991 Aug; 28(8): 827-37

Auteurs: Auphan N, Boyer C, Andre P, Bongrand P, Schmitt-Verhulst AM

Résumé

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.

Lien vers Pubmed [PMID] – 1678858