Characteristics of a monoclonal antibody (WT-31) that recognizes a common epitope on the human T cell receptor for antigen

J Immunol. 1985 Sep;135(3):1922-8.

Abstract

We describe a monoclonal antibody, WT-31, that reacted with all human T lymphocytes. Electrophoretic analysis of the material reacting with WT-31 revealed that it precipitated predominantly an 80-kD disulfide-linked heterodimer from the cell surface-labeled T leukemic cell line HPB-ALL. This heterodimer was identical to the one precipitated with a recently described monoclonal reagent, T40/25, which recognizes a clonotypic structure on HPB-ALL. The target antigen of WT-31 comodulated with T3 after incubation of T cells with excess anti-T3 antibody, indicating that the WT-31 target antigen is associated with T3. We also found that anti-T3 reagents, but not the clonotypic reagent T40/25, blocked binding of FITC-labeled WT-31 to HPB-ALL cells. This indicates that the T cell receptor epitope recognized by WT-31 is located close to the epitopes recognized by the anti-T3 reagents anti-Leu-4 and SPV-T3b but distal from the clonotypic T40/25 epitope. Functional studies showed that WT-31 reacts similar to anti-T3 antibodies. It is mitogenic for resting T cells, blocks cytolysis mediated by alloantigen-specific CTL clones, and induces antigen-nonspecific cytolysis by CTL clones against Daudi target cells. WT-31 did not inhibit the formation of conjugates, but it blocked cytolysis just before or during the Ca2++-dependent programming for lysis. We conclude that WT-31 is an antibody that recognizes a common determinant on the T cell receptor for antigen. The present results support the notion that the two chains of the T cell receptor (alpha and beta) form a functional protein ensemble with the three invariable T3 polypeptide chains (T3-gamma-, delta-, epsilon).

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Antibodies, Monoclonal / immunology*
  • Antibodies, Neoplasm / immunology
  • Antigens, Neoplasm / immunology
  • Antigens, Surface / immunology*
  • Cell Line
  • Cytotoxicity, Immunologic
  • Epitopes
  • Humans
  • Leukemia, Lymphoid / immunology*
  • Macromolecular Substances
  • Molecular Weight
  • Receptors, Antigen, T-Cell / immunology*
  • T-Lymphocytes / immunology*
  • T-Lymphocytes, Cytotoxic / immunology

Substances

  • Antibodies, Monoclonal
  • Antibodies, Neoplasm
  • Antigens, Neoplasm
  • Antigens, Surface
  • Epitopes
  • Macromolecular Substances
  • Receptors, Antigen, T-Cell