T cell receptor idiotypes are controlled by genes in the heavy chain linkage group and the major histocompatibility complex.
Explore the source record for details and available documents.
Antigens↗
Biomedical subjects
K Eichmann
Publications and source records attributed to K Eichmann.
Aged murine killer T-cell clones acquire specific cytotoxicity for P815 mastocytoma cells.
T-cell clones that grow continuously in tissue culture have become a major tool for studying the properties of T lymphocytes. It is therefore important to know to what extent such clones resemble their normal counterparts. Several reports have appeared recently which demonstrate that long-term T-cell lines may lose the specificity for which they were initially selected and acquire cytotoxic activity to a variety of targets, typical of the activity displayed by natural killer cells. We now report a number of instances in which murine cytotoxic T-cell clones have lost their original specific cytotoxic activity but have acquired strong specific cytotoxic activity for P815 mastocytoma target cells. Loss of the original specificity was usually observed after continuous in vitro cultivation for more than 6 months. We propose that this novel type of cytotoxicity should be called aged killer activity.
Animals↗
Preferential expression of a defined T-cell receptor beta-chain gene in hapten-specific cytotoxic T-cell clones.
A multitude of different antigens can be recognized by T cells through specific receptors. Both the alpha- and beta-chains of the T-cell receptor contribute to the antigen recognition portion. The repertoire of beta-chain variable region (V beta) gene segments is limited to some 20 elements which seem to be used randomly in different T cells. Diversity at the beta-chain level can be created in several ways: a multiplicity of germline gene segments; combinatorial diversity by rearranging different V, diversity (D), joining (J) and constant (C) region elements; junctional diversity by joining gene segments at different sites; N-region diversity, that is, insertion of random nucleotides at junctional sites; and somatic mutation. However, the major sources and the extent of diversity of the T-cell receptor are unclear. To address this issue, 42 H-2Kb-restricted, 2,4,6-trinitrophenyl (TNP)-specific cytotoxic T-cell (Tc) clones from C57BL/6 mice were characterized with respect to expression of different beta-chain gene segments in messenger RNA using specific oligonucleotide probes. We report here that nearly half of the Tc clones use identical elements for productive beta-chain gene rearrangement. Thus, there is a restriction in the use of beta-chain gene segments in this panel of Tc clones which favours a particular V beta--D beta--J beta--C beta combination with a defined D beta element.
Animals↗
Developmentally regulated expression of the transmembrane adaptor protein trim in fetal and adult T cells.
TRIM is a recently identified transmembrane adaptor protein which is exclusively expressed in T cells and natural killer (NK) cells. In peripheral blood T cells TRIM has been reported to coprecipitate, comodulate, and cocap with the T-cell receptor (TCR), suggesting that it is an integral component of the TCR/CD3/zeta complex. Here we investigate the expression of TRIM mRNAs and proteins in developing thymocytes. Two splicing isoforms with open reading frames are observed, namely a full length (TRIM) and a truncated version (DeltaTM-TRIM). The latter lacks the extracellular and transmembrane domains as well as the first 10 cytoplasmic aminoacids and is significantly expressed only as mRNA in early fetal thymocytes. TRIM mRNA is detected in all mainstream thymocyte subsets in adult mice. TRIM protein, in contrast, first appears in the DN2 (CD44+ CD25+) subset of adult double negative (DN) cells. In fetal thymocyte development, TRIM mRNA is seen from dg 14.5 onwards whereas TRIM protein appears first on dg 16.5. In contrast to the adult, the TRIM protein was seen in a subset of fetal DN1 cells. In fetal and adult thymocytes, TRIM protein expression was highest in DN2, DN3 (CD44-25+) and in DP cells, compatible with a functional role at or around phases of thymic selection.
Adaptor Proteins, Signal Transducing↗