Correspondence between functionally significant sequences in immunoglobulin and the T cell receptor for antigen.

Abstract

Much has been written about the “dual recognition” properties of the T cell receptor, and in a simplistic sense, the immune recognition of T cells is fundamentally different from the recognition properties of immunoglobulin molecules or peptide receptors in general. The unusual feature of the T cell antigen receptor is that it recognizes and presumably binds to two separate molecules located on the surface of B cells or macrophage/dendritic cells. One of these molecules is always a major histocompatibility complex (MHC)-encoded molecule, and the other is usually a polypeptide antigen. The structure of a receptor that recognizes two separate molecules has been the topic of many speculative theories; most of these theories have concentrated on the number of receptor subunits, the number of binding sites, and the affinity of the receptor for the various ligend components. The topic of this report concerns the overall structure of the T cell antigen receptor as determined by gene cloning and DNA sequencing, and the structure of the T cell receptor variable region domains expressed by T cells specific for defined antigens. These data indicate that the structure of the T cell antigen receptor is analogous to that of immunoglobulin molecules, and the same principles of antigen recognition apply to each.KeywordsMajor Histocompatibility ComplexCell CloneMajor Histocompatibility Complex MoleculeBeta ChainCell Antigen ReceptorThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.