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C Murre

Publications and source records attributed to C Murre.

72 records · Page 4Linked to original sources
PubMed1986

Recognition of the alpha-1 and alpha-2 domains of H-2 molecules by allospecific cloned T cells.

Previously we had shown that allospecific bulk cultures of cytolytic T lymphocytes lysed the products of cloned class I major histocompatibility genes expressed after DNA-mediated gene transfer. In these experiments, performed by using cloned allospecific T cell effectors, a T cell hybridoma, and recombinant DNA technology, we have been able to map determinants recognized by these T cell clones to the alpha-1 domain of H-2Dd and the alpha-2 domain of H-2Ld (four of eight clones). Target cells used were L cells (H-2k), expressing wild type or hybrid H-2 antigens of H-2d origin. Thus, for the first time determinants recognized by cloned T cells are found in the recombined alpha-1 and alpha-2 domains.

Amino Acid Sequence↗
PubMed1986

Human T-cell gamma chain genes: organization, diversity, and rearrangement.

The human T-cell gamma chain genes have been characterized in an attempt to better understand their role in immune response. These immunoglobulin-like genes are encoded in the genome in variable, joining, and constant segments. The human gamma genes include at least six variable region genes, two joining segments, and two constant-region genes in germline DNA. Variable and joining segments recombine during the development of T cells to form rearranged genes. The diversity of human gamma genes produced by this recombinational mechanism is greater than that produced by the murine genome but is more limited than that of other immunoglobulin-like genes.

Animals↗
PubMed1986

AKR murine thymic leukemias are from a distinct thymic cell lineage and do not express the beta chain of the T-cell antigen receptor.

Characterization of tumors that arise spontaneously in the AKR mouse indicates that they are derived from cells of a distinct T-cell lineage. Cells in this subclass bear surface antigens, designated Tpre, Tthy, Tind, and Tsu, which are encoded by genes in the Tsu linkage group on murine chromosome 12. We have examined the rearrangement and expression of genes encoding the T-cell alpha, beta, and gamma chains in these tumors. Although these cells contain alpha-chain mRNA, they do not produce a normal-sized beta-chain mRNA. Most of them also lack gamma-chain mRNA. Each thymic leukemia was derived from a cell arrested at a different stage of development as defined by their expression of terminal deoxynucleotidyl transferase and Thy-1 mRNA. The data presented here are consistent with a model in which thymocytes expressing Tpre, Tthy, Tind, or Tsu undergo somatic development parallel to the development of other T cells. However, these thymocytes do not appear to differentiate into cells bearing alpha-beta heterodimers of the T-cell antigen receptor.

Animals↗
PubMed1986

Cloning and sequence analysis of complementary DNA encoding an aberrantly rearranged human T-cell gamma chain.

Complementary DNA (cDNA) encoding a human T-cell gamma chain has been cloned and sequenced. At the junction of the variable and joining regions, there is an apparent deletion of two nucleotides in the human cDNA sequence relative to the murine gamma-chain cDNA sequence, resulting simultaneously in the generation of an in-frame stop codon and in a translational frameshift. For this reason, the sequence presented here encodes an aberrantly rearranged human T-cell gamma chain. There are several surprising differences between the deduced human and murine gamma-chain amino acid sequences. These include poor homology in the variable region, poor homology in a discrete segment of the constant region precisely bounded by the expected junctions of exon CII, and the presence in the human sequence of five potential sites for N-linked glycosylation.

Amino Acid Sequence↗
PubMed1986

Biochemical and functional analyses of a secreted H-2Ld molecule.

A truncated H-2Ld gene was constructed by deleting the transmembrane and cytoplasmic exons. The truncated H-2Ld gene was introduced into mouse L cells using the thymidine kinase gene as a selectable marker. Transformants were isolated and screened for the presence of truncated H-2Ld antigen. The truncated H-2Ld gene product was present in both the cytoplasm and culture medium, but not on the cell surface. The truncated H-2Ld antigen was stable in culture medium for at least 9 h and was secreted into the medium at a rate similar to the kinetics with which complete H-2 antigens reach the cell surface. Transformants expressing the truncated H-2Ld molecule were not recognized by cytotoxic T lymphocytes specific for the H-2Ld antigen.

Animals↗
PubMed1986

Rearrangement and expression of T-cell antigen receptor genes in human T-lymphocyte tumor lines and normal human T-cell clones: evidence for allelic exclusion of Ti beta gene expression and preferential use of a J beta 2 gene segment.

The gene encoding the beta chain of the human T-cell receptor for antigen is composed of variable (V), diversity (D), joining (J), and constant (C) gene segments which undergo specific rearrangements during T-lymphocyte ontogeny. Southern blot analyses of seven human T-cell tumor lines and normal human T-lymphocyte clones revealed that most of these T-cell lines rearrange their Ti beta genes differently. The T-cell tumor line HPB-MLT rearranges and transcribes both of its Ti beta genes. Cloning and sequencing of the Ti beta cDNAs corresponding to these rearrangements revealed that one of the rearranged Ti beta genes is defective, while the other is functional and corresponds to the Ti beta protein expressed on the surface of these cells. Thus, this cell line displays a pattern of allelic exclusion of Ti beta gene expression. A comparison of four C beta 2-containing Ti beta cDNAs from three different cell lines revealed that three of the four utilize the same J beta 2.5 gene segment joined to different D beta and V beta genes, suggesting that there may be preferential use of this J gene during J beta 2 rearrangements. Hybridization analyses with probes for the alpha and beta genes of the T-cell receptor and the T-cell-specific T gamma gene revealed that HPB-MLT cells appear to express approximately equivalent amounts of RNA corresponding to each of the rearranged Ti alpha and Ti beta genes. However, they express a much lower level of T gamma RNA.

Alleles↗
PubMed1986

T cell receptor gene rearrangements define a monoclonal T cell proliferation in patients with T cell lymphocytosis and cytopenia.

We have used probes from the T cell receptor beta and gamma chain loci to investigate the clonality of T lymphocytes in eight patients with T cell lymphocytosis and cytopenia (TCLC). This syndrome, which is strongly associated with rheumatoid arthritis, is characterized by peripheral blood and bone marrow lymphocytosis and neutropenia, red cell aplasia, or both. By means of T cell monoclonal antibodies and flow cytometry, T lymphocytes from patients with this syndrome have been shown to have characteristic immunologic features. Investigators have disagreed as to whether the syndrome represents a T cell malignancy or a more benign immunologic disorder. DNA from five of five patients with symptomatic "classic" T cell lymphocytosis with cytopenia demonstrated unique rearrangements of the T cell receptor beta chain locus, whereas neither of two patients with atypical features showed rearrangement. In addition, we found evidence for gamma chain rearrangement in those DNAs with clonal beta chain rearrangement. We thus postulate that the classic form of this syndrome is associated with a monoclonal proliferation of T cells. Its potential relationship to T cell chronic lymphocytic leukemia is discussed.

Aged↗
PubMed1985

A novel mechanism of somatic rearrangement predicted by a human T-cell antigen receptor beta-chain complementary DNA.

The T-cell antigen receptor is a cell surface molecule vital in mediating the cellular immune response. The arrangement and rearrangement of the gene segments encoding the beta-chain polypeptide of the receptor are similar to those of immunoglobulin gene segments. The two constant region genes of the human T-cell antigen receptor are 8 kilobases apart with a cluster of joining segments located 5' of each constant region gene. Although most beta-chain gene rearrangements involve the variable, diversity, and joining segments, analysis of a beta-chain complementary DNA clone suggests the occasional occurrence of another type of rearrangement.

Base Sequence↗
PubMed1985

Differential expression of H-2Dd and H-2Ld histocompatibility antigens.

To determine why the H-2Dd antigen is expressed on the surface of transfected cells at a rate several-fold higher than an analogously transfected H-2Ld molecule, we analyzed both previously described and new H-2 hybrid genes. These genes were constructed by exchanging domains between H-2 genes. Quantitative radioimmunoassay indicates that the region of the H-2Dd molecule responsible for its enhanced expression resides in the polymorphic N domain, the first domain of the mature class I molecule.

Animals↗
PubMed1985

An Ia-positive mouse T-cell clone is functional in presenting antigen to other T cells.

In this report we present data demonstrating the endogenous expression of I-region associated (Ia) antigens on a cloned line of mouse T cells, CTLL, as well as transcription of the invariant chain gene in these cells. We demonstrate further that this Ia-bearing T-cell clone, CTLL, can utilize the expressed Ia molecules to present antigen to Ia-restricted antigen-specific T cells.

Animals↗
PubMed1985

beta 2-Microglobulin from serum associates with several class I antigens expressed on the surface of mouse L-cells.

Bovine beta 2-microglobulin (beta 2-m) present in fetal calf serum (FCS) is able to replace endogenous beta 2-m associated with several class I antigens from human and mouse cells maintained in culture [Bernabeu et al. (1984) Nature, Lond. 308, 642-645]. Here we show that human HLA-A2 and HLA-B7, as well as mouse H-2Ld and H-2Dd heavy chains expressed after gene transfer in mouse L-cells, associate to a large extent with bovine beta 2-m. We also demonstrate that bovine beta 2-m associated with the endogenous H-2Kk/Dk heavy chains generates an antibody response when L-cells are injected into syngeneic C3H mice.

Animals↗
PubMed1985

Polymorphism of murine major histocompatibility Class I antigen: assignment of putative allodeterminants to distinct positions of the amino acid sequence within the first external domain of the antigen.

Forty-five new monoclonal antibodies reacting with the mouse H-2Dd antigen have been established. The specificities of 34 of these antibodies were mapped into the first external domain (N) of the Dd antigen by testing reactivities with the products of mosaic H-2 genes in which the coding sequences of the first and/or the second external domains of the H-2Dd genes were recombined in vitro with the remaining portion of the H-2Ld gene. These antibodies reacted with at least 13 distinct allodeterminants located in the N domain, composed of 91 amino acids, as judged from panel tests carried out on various H-2 haplotypes. To assign possible positions of antigenic determinants of these and other anti-H-2Dd antibodies, we compared primary sequences of seven H-2 antigens and searched for correspondence between the pattern of amino acid substitutions in the N domain, allowing 15 positions to be assigned for the antigenic sites. These putative antigenic determinants were assessed for possible relationships with several parameters of protein secondary structure postulated according to predictive methods. Many of these sites appear to be associated with greatest local hydrophilicity, known to correlate with sites of antibody binding in various proteins. We therefore propose that some of the correspondences found in this work represent structural correlates of allodeterminants.

Amino Acid Sequence↗
PubMed1984

Dissection of serological and cytolytic T lymphocyte epitopes on murine major histocompatibility antigens by a recombinant H-2 gene separating the first two external domains.

A novel H-2 gene in which the first external (N) domain of the H-2Ld antigen was replaced with that of the H-2Dd antigen was constructed and introduced into L cells. A transformant expressing the products of the hybrid gene was studied for binding to monoclonal antibodies specific for H-2Ld and H-2Dd antigens. It was found that serological determinants are distributed both in the N (Dd) and Cl (Ld) domains. Determinants recognized by allospecific cytotoxic T lymphocytes (CTLs) and virus-specific CTLs also mapped to the N and Cl domains. Determinants recognized by vesicular stomatitis virus (VSV)-specific effect cells, however, were not present on the recombinant molecule. These results show that a recombinant gene of two H-2 antigens in which the first external domain has been reshuffled can express a functional H-2 antigen that can then be used to map serological and CTL determinants to specific domains.

Animals↗
PubMed1984

Cytotoxic T lymphocyte recognition of class I H-2 antigens after DNA-mediated gene transfer.

Cytotoxic T lymphocyte (CTL) recognition sites on class I major histocompatibility complex molecules have been investigated by several laboratories by using cloned genes expressed on mouse L cells by DNA-mediated gene transfer. Recombinant genes, constructed by restriction endonuclease treatment of cloned H-2Dd and Ld genes and exchange of the N and C1 exons (exon shuffling) have provided an additional tool. These hybrid H-2 molecules expressed on L cells have been used as targets to achieve more precise localization of site(s) recognized by allospecific and virus-specific CTLs. CTL systems were chosen that limit recognition to either the Dd or Ld alloantigen or to virus and Dd or Ld complexes. Using this approach, we were able to map essential restricting site(s) to the N and/or C1 domains. Additional evidence is presented that the cytoplasmic tail of H-2 may be involved in interactions with some viral antigens and effect the formation of an immunogenic complex.

Animals↗
PubMedDate not supplied

Construction, expression and recognition of an H-2 molecule lacking its carboxyl terminus.

A mouse major histocompatibility antigen (H-2) gene, encoding a novel H-2Ld molecule lacking its intracytoplasmic domain, has been constructed and introduced into mouse L-cells. The novel H-2 molecule is found on the surface of the transfected cells at the same level as L-cells transfected with the native H-2Ld gene. Allo- and influenza-specific cytotoxic T lymphocytes can recognize the truncated H-2 gene product nearly as efficiently as the normal H-2Ld gene product. However, vesicular stomatitis virus-specific cytotoxic T lymphocytes recognize the truncated H-2Ld molecule less efficiently than the complete H-2Ld product. The rate of capping of the truncated H-2Ld molecule was investigated and found to be the same as that of the complete H-2Ld gene product.

Amino Acid Sequence↗
PubMedDate not supplied

Human gamma-chain genes are rearranged in leukaemic T cells and map to the short arm of chromosome 7.

Three gene families that rearrange during the somatic development of T cells have been identified in the murine genome. Two of these gene families (alpha and beta) encode subunits of the antigen-specific T-cell receptor and are also present in the human genome. The third gene family, designated here as the gamma-chain gene family, is rearranged in murine cytolytic T cells but not in most helper T cells. Here we present evidence that the human genome also contains gamma-chain genes that undergo somatic rearrangement in leukaemia-derived T cells. Murine gamma-chain genes appear to be encoded in gene segments that are analogous to the immunoglobulin gene variable, constant and joining segments. There are two closely related constant-region gene segments in the human genome. One of the constant-region genes is deleted in all three T-cell leukaemias that we have studied. The two constant-region gamma-chain genes reside on the short arm of chromosome 7 (7p15); this region is involved in chromosomal rearrangements identified in T cells from individuals with the immunodeficiency syndrome ataxia telangiectasia and observed only rarely in routine cytogenetic analyses of normal individuals. This region is also a secondary site of beta-chain gene hybridization.

Amino Acid Sequence↗
PubMedDate not supplied

Human T-cell gamma genes contain N segments and have marked junctional variability.

The gamma-chain genes are encoded by immunoglobulin-like gene segments in germline DNA which rearrange during the somatic development of T cells to form an active gene. The protein produced by these genes has not been identified and the diversity of the proteins that the genes can express has not been determined. We expect that the diversity of expressed gamma-chains is produced by the same three mechanisms that produce diversity of other immunoglobulin-like genes: (1) germline variable (V) and joining (J) region repertoires; (2) somatic mutation; and (3) junctional diversity. To define the contribution of each of these mechanisms to the generation of gamma-chain diversity, several gamma-chain complementary clones and rearranged gamma-chain genes have been characterized. Most of these clones seem to encode a defective gamma-chain, the variable- and constant-region portions being joined such that they would not be translated in the same reading frame. Here we report that the germline J-region diversity of the human T-cell gamma-chain is very limited and that somatic mutation does not contribute to the diversity of the gamma-chains encoded by the cloned segments. However, the junctional diversity of these gamma-chain genes is extensive. We suggest that N sequences (template-independent sequences) have been inserted enzymatically into all of the gamma-chain genes characterized.

Base Sequence↗