Modulation of CD4 by antigenic activation.

C M Weyand; J Goronzy; C G Fathman

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PubMed · 3100638

Modulation of CD4 by antigenic activation.

C M Weyand·J Goronzy·C G Fathman

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Abstract

Cell surface expression of CD4, an invariant membrane glycoprotein, is characteristic of the MHC class II-restricted T cell helper/inducer subset. Although the specificity and restriction patterns of T lymphocytes are determined by the T cell receptor for antigen, CD4 might represent an additional "interaction" molecule that is required to strengthen the interaction between T cells, antigen, and antigen-presenting cells. In this manuscript, we have shown that the cell surface expression of CD4 is correlated with activation of T cells. Data presented in this paper have demonstrated, for the first time, that antigenic stimulation of human T cell clones caused a decrease in the expression of the CD4 marker (as well as to the CD3 marker) to about 50% of the constitutive level. As previously demonstrated, PMA caused modulation of CD4 and CD3, which suggested that phosphorylation by protein kinase C played a crucial role in the regulation of the expression of both markers. The parallel down-regulation of CD3 and CD4 after antigen stimulation suggested that both markers might be members of a multimolecular complex mediating T cell activation.

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Antigens, Differentiation, T-Lymphocyte Antigens, Surface Cell Differentiation Endocytosis Humans Lymphocyte Activation T-Lymphocytes Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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C M Weyand, J Goronzy, C G Fathman. 1987-03-01. Modulation of CD4 by antigenic activation.. https://pubmed.ncbi.nlm.nih.gov/3100638/

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