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T Moriuchi

Publications and source records attributed to T Moriuchi.

99 records · Page 6Linked to original sources
PubMed1979

Serological characterization of rat leukemia lines, DBLA-1, -6, and -9.

Three lines of rat leukemia, DBLA-1, -6, and -9, were studied serologically by complement-dependent cytotoxicity test. DBLA-1, -6, and -9 were killed by anti-lymphocyte sera, anti-Thy-1.1 sera, and rabbit anti-rat brain sera absorbed with AKR/J brain. However, anti-T and anti-B lymphocyte sera had no cytotoxic effect on DBLA-1, -6, and -9. Furthermore, DBLA-6 and -9 did not absorb the cytotoxic activity of anti-T serum on thymocytes, while DBLA-1 slightly absorbed the cytotoxic activity. These results indicate that DBLA-1, -6, and -9 are of lymphoid origin and possess rat Thy-1 antigens, but lack mature T-lymphocyte antigens. On the other hand, peroxidase-positive myelogenous leukemia L1005 failed to react with any of the antisera used.

Animals↗
PubMed1979

Heterologous antiserum to a subpopulation of thymocytes and lymphomas in rats.

Immunization of rabbits with rat leukemia DBLA-6 resulted in the production of antisera which upon absorption with hepatoma cells were specific for rat immature T lymphocytes. The antisera showed cytotoxicity against thymocytes and killed 75 approximately 90% of them, whereas the antisera had no cytotoxic effect on peripheral lymphocytes from the spleen, lymph node, and bone marrow of rats. The antisera also showed cytotoxicity against rat lymphatic leukemia and lymphoma cells of all lines tested but not against rat myelogenous leukemia and erythroleukemia cells. The cytotoxic activity of anti-DBLA-6 serum was completely absorbed with rat brain or thymocytes.

Animals↗
PubMed1979

Topographical distribution and association of tumor--associated antigens and their role in antigenicity in rat tumor cells.

The antigenicity of tumor-associated antigen (TAA) was compared between 3-methylcholanthrene-induced rat fibrosarcoma KMT-17 and Friend murine leukemia virus-infected KMT-17 (FV-KMT-17) cells. The antigenicity was classified into immunosensitivity and immunogenicity, and studied from the viewpoint of humoral immunity. The immunosensitivity to anti TAA antibodies increased by artificial infection of KMT-17 cells with Friend virus. The results suggested that an increase of lateral mobility of TAA on the cell surface contributes to the increase of immunosensitivity. Concerning the immunogenicity of TAA, an augmentation of anti-TAA antibody formation was demonstrated when FV-KMT-17 cells were used as the immunogen. In this case, a physical association between TAA and virus-associated antigen (VAA) was suggested to be very important to increase the immunogenicity of TAA.

Animals↗
PubMed1976

Xenogenization of rat erythroid cells by lymphatic leukemia virus: its role in induction of autoimmune hemolytic anemia.

Newborn rats given injections of low doses of Friend lymphatic leukemia virus subsequently developed hemolytic anemia characterized by production of antierythrocyte autoantibody. Electron microscopy showed C-type virus particles budding from the cell membrane not only of lymphoid cells but also of erythrocyte percursor cells in bone marrow and spleen, suggesting that the erythroid cells were infected by the virus. In addition, erythrocyte precursor cells expressed virus-induced cell surface antigens detected by cytotoxicity tests. Normal syngeneic rats preimmunized with a Friend lymphatic leukemia virusinduced tumor and subsequently inoculated with bone marrow, spleen cells, or reticulocyte-rich fraction derived from other rats injected with high doses of the virus at birth produced cytotoxic antibody to the virus-induced tumor and antierythrocyte autoantibody. In contrast, rats subsequently inoculated with virus-infected thymus or lymph node cells produced cytotoxic antibody but not antierythrocyte autoantibody. These results indicate that "xenogenization," previously shown for tumor cells and normal lymphoid cells, is also observed for rat erythroid cells and, further, that xenogenization of erythroid cells by Friend lymphatic leukemia virus is one of the most important factors in induction of autoimmune hemolytic anemia.

Anemia, Hemolytic, Autoimmune↗
PubMedDate not supplied

The heavy chain of human B-cell alloantigen HLA-DS has a variable N-terminal region and a constant immunoglobulin-like region.

The HLA-D region of the major histocompatibility complex (MHC) of man encodes polymorphic glycoproteins found predominantly on the cell surfaces of B cells and macrophages. These proteins mediate interactions, required for the induction of immune responses, among cells of the immune system and consequently are referred to as Ia (immune-response associated). Two families of Ia molecules, DR and DS (also known as DC), have been defined, the former analogous to the I-E (ref. 1) and the latter to the I-A molecules of the murine MHC. Both DR and DS molecules consist of two noncovalently associated polypeptide chains with molecular weights of 33,000 and 28,000, designated alpha and beta, respectively. The polymorphism of DR molecules is due to structural variation in the small subunit, DR beta, with the large subunit, DR alpha, being constant in structure. In contrast, both subunits DS alpha and DS beta are structurally variable when DS allotypes are compared. We have now isolated a cDNA clone from a DR7 cell line that contains the entire coding sequence for the DS alpha subunit and have compared its predicted amino acid sequence with that previously deduced from a DS alpha cDNA clone isolated from a DR4,w6 cell line. This comparison reveals that 10 of 11 amino acid differences are located within the alpha 1 (N-terminal) domain and that the alpha 2 or immunoglobulin-like domains are identical.

Amino Acid Sequence↗
PubMedDate not supplied

Structural organization of the rat thy-1 gene.

Thy-1 is a differentiation marker expressed predominantly on thymocytes, T cells and brain tissue. Its presence on murine peripheral T cells but not B cells has long been used to distinguish between these two populations of lymphocytes. Although analogues of Thy-1 have been described in several mammalian species, its tissue distribution in different species varies widely, precluding its use as T-cell-specific marker. The Thy-1 molecule is a cell-surface glycoprotein of relative molecular mass 18,000, one-third of which represents carbohydrate; the protein moieties of the rat and murine Thy-1 molecules have been sequenced and found to consist of 111 and 112 amino acids, respectively. An unusual aspect of Thy-1 is the apparent absence of a hydrophobic segment comparable to that observed in other membrane glycoproteins which would allow integration of Thy-1 within the membrane lipid bilayer. This has prompted speculation that Thy-1 is anchored to the cell surface by some other hydrophobic component such as glycolipid. Here we report the structure of thy-1 complementary DNA and genomic clones and describe the exon-intron organization of the gene. More importantly, our data indicate that Thy-1 is initially synthesized as a molecule of 142 amino acids, 31 amino acids longer at the carboxyl end than the Thy-1 molecule isolated and characterized by Campbell et al. An extremely hydrophobic region of 20 amino acids lies within this 31-amino acid stretch and may represent the transmembrane segment responsible for anchoring Thy-1 to the cell membrane.

Amino Acid Sequence↗
PubMedDate not supplied

Unsaturated fatty acid feeding prevents the development of acute hepatitis in Long-Evans cinnamon (LEC) rats.

To investigate the effects of dietary alpha-linolenic acid (18:3, n-3; alpha-LNA) and linoleic acid (18:2, n-6; LA) on the development of hereditary hepatitis, we compared incidences and grades of acute hepatitis between the Long-Evans cinnamon (LEC) rats fed with safflower oil-supplemented diet and perilla oil-supplemented diet. Both safflower and perilla oil supplemented diets reduced the incidence of hepatitis and significantly prolonged its onset as compared to the non-supplemented conventional diet. No significant difference was observed between safflower and perilla oil diets in the rats of incidence of hepatitis. At the age of 16 weeks, just before the onset of hepatitis, serum levels of transaminase (AST, ALT) and concentration of copper in rats fed with both test diets were significantly reduced as compared with that of rats fed alpha-linolenate and linoleate have an inhibitory effect on the development of hepatitis in LEC rats due to the prevention of serum copper elevation.

Acute Disease↗