Showing papers by "Tak W. Mak published in 1984"

A human T cell-specific cDNA clone encodes a protein having extensive homology to immunoglobulin chains

Abstract: We have cloned and sequenced a human mRNA specific for mammalian T-lymphoid cells The message was found to be expressed in human and murine T lymphoblasts, thymocytes and phytohaemagglutinin-stimulated T lymphocytes The protein deduced from the cDNA sequence has a molecular weight of 34,938 and shows extensive similarity to the entire length of the variable, joining and constant regions of mammalian immunoglobulin light chains In addition, the relative positions of the cysteine residues are similar to those of the light chains of murine and human immunoglobulin molecules These properties suggest that the cDNA clone may correspond to a message that specifies part of the human T-cell receptor

Genes Encoding the Human T Cell Antigen Receptor

Abstract: An essential property of the immune response is its ability to distinguish between self and non-self and to generate enormous diversity in antibody and T cell immune responses. While the genetic and molecular mechanisms responsible for antibody diversity have been largely elucidated over the last decade (Honjo 1983, Tonegawa 1983) the characterization of the T cell antigen recognition structure, the T cell receptor, and the diversification of the receptor repertoire have been an elusive goal of molecular immunologists for many years (Kronenberg et al. 1983, Janeway 1983). One of the most interesting characteristics of T lymphocyte behavior is its antigen recognition in the context of the major histocompatibility complex (MHC) (Golub 1980), a phenomenon known as MHC restriction. Several excellent reviews have been written on this subject recently (Goodman & Sercarz 1983, Hood et al. 1983, Singer & Hodes 1983). This characteristic nature of antigen recognition by T cells and the repeated failures to isolate the T cell receptor genes, despite extensive efforts, have led to much speculation as to the nature of these genes. Based on the rationale that nature would not have evolved a separate complex mechanism for antigen recognition by B cells and T cells, it has been proposed that the structure of the T cell antigen receptor must be very similar to that of immunoglobulins (Ig). This prediction, called the \"minimal hypothesis\" theorizes that the T cell receptor may have a structure possessing binding sites composed of immunoglobulin variable segments, but its constant segments are not necessarily identical to those of antibodies (Eichmann 1978, Janeway & Jason 1980). However, the use of antiserum specific for inmiunoglobulin chains to search for crossreacting determinants on T cells has produced controversial results, while the use of molecular probes has resulted in uniformly negative data. The persistent frustration in resolving this controversy has led to postulation by other workers