Antigen-specific T cell unresponsiveness in cloned helper T cells mediated via the CD2 or CD3/Ti receptor pathways.
Lamb JR., Zanders ED., Sewell W., Crumpton MJ., Feldmann M., Owen MJ.
We have investigated the role of the CD2 protein in the negative regulation of immune function and report that similar to antigen and anti-CD3, the monoclonal anti-CD2 antibodies (T112 and T113) can induce specific unresponsiveness. Antigen and anti-CD2 tolerogenic signals both down-regulated the phenotypic expression of CD3-Ti. In contrast CD2 surface expression was up-regulated after exposure to peptide and down-regulated after anti-T112 and T113 preincubation. However, in both instances interleukin 2 receptor surface levels were increased. These phenotypic changes could only be partly explained by variations in the levels of the transcripts encoding the CD3-Ti and CD2 molecules.