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T Moriuchi

Publications and source records attributed to T Moriuchi.

At least 91 records · Page 5Linked to original sources
PubMed1985

A hydrophobic transmembrane segment at the carboxyl terminus of thy-1.

The mode of integration of the glycoprotein thy-1 within the cell membrane has been controversial due to an apparent lack of a transmembrane hydrophobic segment. Rat and mouse complementary DNA and genomic clones encoding the thy-1 molecule have been isolated and sequenced. These studies have enabled us to determine the intron-exon organization of the thy-1 gene. Furthermore, they have revealed the existence of a sequence which would encode an extra segment (31 amino acids) at the carboxyl terminus of the thy-1 molecule. These extra amino acids include a 20-amino acid hydrophobic segment which may be responsible for integration of thy-1 within the plasma membrane.

Amino Acid Sequence↗
PubMed1985

Nucleotide sequence of an HLA-DQ alpha chain derived from a DRw9 cell line: genetic and evolutionary implications.

Three families of human Ia molecules, DP, DQ, and DR, have previously been defined. A cDNA clone, pDSH-9.1, encoding the alpha chain of a DQ molecule derived from an HLA-DRw9 homozygous cell line has been isolated and sequenced. Comparison of the nucleotide and predicted protein sequence to those of other DQ alpha subunits reveals that DQ alpha subunits derived from DR4, -7, and -9 cells are very similar to each other but quite different from a DQ alpha subunit derived from a DRw6 cell line. These studies suggest that certain Ia haplotypes have a common evolutionary history. Furthermore, in the context of current serologic and biochemical knowledge, they suggest that the gene encoding the DQ alpha subunit is in strong linkage disequilibrium with the DR locus.

Amino Acid Sequence↗
PubMed1985

Isolation and characterization of mouse Thy-1 genomic clones.

The mouse Thy-1.2 gene was isolated from a C57Bl/6 cosmid library and its nucleotide sequence was determined from an 8-kilobase-long EcoRI fragment. The predicted amino acid sequence indicates that the mouse Thy-1 molecule contains a 19 amino acid leader peptide and the 112 amino acids reported previously from protein sequence analysis, plus 31 extra amino acids at the carboxyl terminus. These 31 amino acids contain a stretch of 20 amino acids, at positions 124-143, which is highly hydrophobic. RNA transfer blot analysis of RNA from mouse tissues indicates that the sequence coding for these 31 amino acids is present on poly(A)-containing RNA of brain and thymus tissues. This hydrophobic segment very likely provides the basis for integration of Thy-1 within the plasma membrane. The entire coding sequence of Thy-1 is distributed among three exons, encoding amino acid residues -19 to 8, -7 to 106, and 107 to 143, respectively. Comparison of the mouse and rat Thy-1 genes shows that both have a similar gene organization and encode a highly conserved transmembrane segment.

Amino Acid Sequence↗
PubMed1985

Thy-1: a hydrophobic transmembrane segment at the carboxyl terminus.

Thy-1 is a membrane glycoprotein distributed throughout mammalian species and expressed on brain tissue and various cells of the hematopoietic lineage. The nucleotide sequences of rat and mouse Thy-1 genes revealed a similar gene organization and the existence of an extra 31 amino acid segment at the carboxyl terminus not described previously. These extra amino acids, highly conserved in both species, include a 20 amino acid hydrophobic segment at the carboxyl terminus, which may be responsible for integration of Thy-1 within the plasma membrane.

Amino Acid Sequence↗
PubMed1985

A case of primary systemic amyloidosis.

An adult patient with primary systemic amyloidosis associated with nephrotic syndrome and complete atrial-ventricular (A-V) block is described. This case was considered to be a slowly progressive primary amyloidosis because of a long time episode of poor appetite and nephrotic syndrome. Temporal pace making of the heart was not effective presumably due to heart muscle damage, pér sé. Autopsy specimens revealed typical features of primary amyloidosis in light microscopy and immunofluorescence. It is suggested that early detection of amyloid fibers in the heart muscles may improve prognosis in patients with primary amyloidosis.

Amyloidosis↗
PubMed1984

Rat Thy-1 antigen has a hydrophobic segment at the carboxyl terminus.

We have isolated a cDNA clone coding for rat Thy-1 antigen from a rat thymocyte cDNA library. The 549 base pairs insert includes the complete coding region of a mature Thy-1 polypeptide of 142 amino acids, 31 amino acids longer than the previously reported glycoprotein sequence. These 31 amino acids contain an extremely hydrophobic region of 26 uncharged amino acids which apparently represent the transmembrane segment that allows for integration within the membrane. The presence of this additional protein segment will solve most of the enigmas regarding the properties of the C-terminal region of Thy-1 antigen.

Amino Acid Sequence↗
PubMed1984

Expression of the Thy-1 glycoprotein gene by DNA-mediated gene transfer.

We isolated a gene encoding the Thy-1.2 glycoprotein from a recombinant library constructed from BALB/c mouse DNA. To evaluate the expression of this cloned gene in different genomic environments, we introduced it into cell lines derived from fibroblast, lymphoid, and neuronal tissues by DNA-mediated gene transfer. When integrated into the genome of mouse L cells, cell-surface Thy-1 can be detected with anti-Thy-1 monoclonal antibodies. These L-cell lines contain between two and four copies of the cloned Thy-1 gene stably integrated in the host genome. After subcloning into a plasmid vector containing the bacterial Eco-gpt gene as a selectable marker, the Thy-1 gene was introduced into the Thy-1-deficient mouse lymphoma AKR1 (Thy-1-d), and the rat neuronal cell line, B50. The resulting transformants also contain two to four copies of the cloned Thy-1 gene but express up to 50-fold more cell-surface Thy-1.2 than the L cell transformants. The expression of vastly differing amounts of cell-surface Thy-1 from similar numbers of genes suggests that the gene encoding this differentiation antigen is under tissue-specific regulation.

Animals↗
PubMed1983

Thy-1 cDNA sequence suggests a novel regulatory mechanism.

Thy-1 was originally defined in mice as a cell-surface alloantigen of thymus and brain with two allelic forms, Thy-1.1 and Thy-1.2 (ref. 1). Subsequently, the Thy-1.1 alloantigenic determinant was identified in rats. In both species, Thy-1 is present in large amounts on thymus and brain cells and in smaller quantities on fibroblasts, epidermal cells, mammary glands and immature skeletal muscle. In many of these tissues the level of Thy-1 expression changes dramatically during cell differentiation. The molecules expressing the Thy-1 antigenic determinant have been isolated from rat and mouse brain cells and have been shown to have a molecular weight of 17,500 (ref. 8). One-third of the Thy-1 molecule is carbohydrate and the remainder is a polypeptide of 111 amino acids whose sequence has been fully determined. We report here the isolation and characterization of a cDNA clone encoding the rat thymus Thy-1 antigen but find that the DNA sequence ends prematurely at a position corresponding to amino acid 103. It appears to be a complete transcript, however, as the last codon is followed directly by a poly(A) tract.

Amino Acid Sequence↗
PubMed1983

Establishment and characterization of a differentiating myeloid cell line obtained from a rat myelomonocytic leukemia.

A long-term suspension culture line (c-WRT-7) was successfully established from a transplantable myelomonocytic leukemia induced by a neonatal injection of Rauscher leukemia virus in a WKA/Hok rat. A c-WRT-7 cell line was capable of being transplanted into syngeneic rats, and when transplanted, increased numbers of macrophage-like cells were observed in the peripheral blood of rats after i.v. injection. In in vitro culture, about 10% of the c-WRT-7 cells naturally differentiated into macrophage-like cells, which adhered to the bottom of a culture flask, and also possessed phagocytic activity. By means of cytological examination, about 30% of the c-WRT-7 cells were observed to be monoblastic with alpha-naphthyl butyrate esterase activity. The nature of these c-WRT-7 cells as a myelomonocytic leukemia line was constant during in vitro passages of more than 30 generations. In vitro treatment of c-WRT-7 cells with lipopolysaccharide, 12-O-tetradecanoylphorbol-13-acetate, or retinoic acid increased the numbers of differentiated cells with phagocytic activity to 80%. Treatment of the c-WRT-7 cells with the inducers also induced 15 to 20% of the cells to differentiate into metamyelocytes and segmented neutrophils. The Fc receptor and the complement receptor both became detectable on the surface of c-WRT-7 cells after treatment with lipopolysaccharide, 12-O-tetradecanoylphorbol-13-acetate, or retinoic acid. However, rosette-forming activity of sheep erythrocytes pretreated with neuraminidase which has been known as a marker of normal rat macrophages was not induced in c-WRT-7 cells. This shows that differentiated leukemic cells are not exactly identical with normal macrophages.

Animals↗
PubMed1983

Establishment and characterization of a transplantable rat myelomonocytic leukemia.

A transplantable myelomonocytic leukemia was established from a leukemia of a WKA/Hok rat which had been inoculated with Rauscher virus at birth. The tumor grew in ascites form in normal syngeneic rats and, after the middle stage of i.p. transplantation, leukemia cells consisting of a mixed population of monocytic and granulocytic cells were observed in the peripheral blood. A complement-dependent cytotoxicity test failed to demonstrate Rauscher virus-related antigen on the tumor cell surface. Membrane marker analysis revealed that most of the tumor cells possessed receptors for both complement and neuraminidase-treated sheep RBC. More than 90% of ascitic tumor cells displayed phagocytic activity and a positive nonspecific esterase reaction. Serum from rats bearing this tumor contained high levels of muramidase. Ultrastructurally, the tumor cells resembled both immature and mature cells of the monocyte-macrophage series. On serial transplantation into the peritoneal cavity, the tumor displayed consistent differentiation from undifferentiated blast cells to monocytes and cells indistinguishable from granulocytes. The karyotype analysis revealed that the modal number of chromosomes of the tumor cells was 81, and no structural abnormalities of chromosomes were observed after quinacrine mustard staining. This transplantable leukemia will provide a useful experimental model for the study of granulocyte-monocyte differentiation and for human myelomonocytic leukemia.

Animals↗
PubMed1982

Altered properties of tumors induced by adenovirus type 12 DNA fragment transformed cells after growth in immunocompetent rats.

The GY1-3-1 cell line, which was derived from a rat cell line transformed by the Ad 12 HindIII-G fragment, can induce tumors in newborn rats but not in mature rats. However, when 10 mature rats were transplanted with a large number of GY1-3-1 tumor fragments, two developed tumors with a long latency period. These two tumors (GY1-3M and GY1-3Y) were quite different in properties from the originally inoculated GY1-3-1 tumor. Tumor transplantation studies revealed that both GY1-3M and GY1-3Y tumors could grow in mature rats and the number of takes with transplanted tumor was 100% with GY1-3M tumor and 40% with GY1-3Y tumor. Histopathologically original GY1-3-1 tumor showed a morphology of undifferentiated sarcoma, while the histologic picture of GY1-3M and GY1-3Y tumors was similar to that encountered in human fibrosarcoma and malignant fibrous histiocytoma, respectively. Both GY1-3M and GY1-3Y tumors, when recultured in vitro, gave rise to cell lines with a fibroblastic appearance although the original GY1-3-1 cell line exhibited an epithelioid morphology. In chromosome analysis, the GY1-3-1 cell line was pseudodiploid, while the cell lines from GY1-3M and GY1-3Y tumors were hyperdiploid or near-triploid. The metacentric marker chromosome, MI, was present in mitotic cells of the GY1-3-1 line and of the GY1-3M tumor lines, but absent from the GY1-3Y tumor lines. By Southern blot hybridization, multiple bands of cellular DNAs from parental GY1-3-1 cells hybridized with labelled Ad 12 HindIII-G, while only a single band hybridized DNAs from both GY1-3M and GY1-3Y tumors.

Adenoviruses, Human↗
PubMed1981

Characterization and classification of rat leukemias and lymphomas by membrane markers.

An immunological characterization of leukemias and lymphomas was made in the rat by using a panel of membrane markers in combination with morphological analysis. In the present study, five antigen markers and three surface markers were used for the characterization of 20 rat leukemias and lymphomas, and it was indicated that they could be divided into at least six groups. Of the lymphomas studied, six thymic lymphomas (Group 1) had the Thy-1.1 antigen, T-cell antigen, and receptors for guinea pig red blood cells; five extrathymic lymphomas (Group 2) lacked T- and B-cell antigens, receptors for guinea pig red blood cells, and surface immunoglobulin, but three of them had complement receptors. An absorption test revealed that Group 2 lymphomas possess a very low amount of the Thy-1.1 antigen compared to Group 1 lymphomas. None of the leukemias studied had detectable T- and B-cell antigen. Four leukemias had undifferentiated blast cell morphology and bore the Thy-1.1 antigen; three leukemias (Group 3) reacted with anti-lymphocyte serum, but one leukemia (Group 4) did not. Two leukemias (Group 5) had only the complement receptor and morphologically showed granulocytic appearance. Three leukemias (Group 6) had none of the membrane markers used and morphologically resembled erythroblasts. Based on these results, an attempt was made to classify these leukemias and lymphomas into T-cell lineage, B-cell lineage, stem cell, myeloid, and erythroid groups, respectively. Furthermore, the stage of differentiation in the lymphocyte maturational pathway of the leukemias and lymphomas belonging to Groups 1 to 4 is discussed.

Animals↗
PubMed1981

Heterologous antiserum to chemically induced rat non-T, non-B leukemia and its application to characterization of rat leukemias.

Antisera to the 1-butyl-1-nitrosourea-induced "non-T, non-B" rat leukemia line DBLA-6 were raised in rabbits. Following absorption with syngeneic hepatoma cells, the antisera were very similar in specificity to antisera raised to rat Thy-1 antigen. Anti-DBLA-6 serum was cytotoxic in the presence of complement against 70 to 90% of thymocytes and 40 to 50% of neonatal spleen cells. In contrast, no significant cytotoxicity was observed against cells from bone marrow, lymph node, spleen, and peritoneum. An absorption test revealed that an antigen recognized by anti-DBLA-6 serum was present in brain tissue but absent in liver and kidney tissues. Nineteen rat leukemias and lymphomas were divided into six groups based on antigenic and morphological characteristics and the presence of receptor for guinea pig red blood cells. These tumors were investigated for the presence of the antigen recognized by anti-DBLA-6 serum. Of the leukemias and lymphomas studied, anti-DBLA-6 serum reacted with all thymic (Group 1) and extrathymic (Group 2) lymphomas and unclassified leukemias (Groups 3 and 4), while all myelogenous leukemias (Group 5) and erythroleukemias (Group 6) were negative. The position of leukemias and lymphomas reactive with anti-DBLA-6 serum in the lymphocyte maturational pathway is discussed.

Animals↗
PubMed1979

Correlation between concanavalin A agglutinability and cytotoxic sensitivity to antiserum against tumor-associated antigen in rat fibrosarcoma cells.

An ip transplantation of 3-methylcholanthrene-induced, transplanted fibrosarcoma KMT-17 cells (1 X 10(8)) grew rapidly and killed syngeneic WKA rats in 3-4 days. Agglutinability induced by concanavalin A (Con A) and antigenic expression of KMT-17 cells were investigated in relation to days after ip transplantation. Agglutinability was highest in 1-day-old cells and lowest in 3-day-old cells. The agglutinability of 3-day-old cells increased again when these cells were transplanted into normal rats. The cytotoxic sensitivity of tumor cells to antiserum against tumor-associated surface antigen (TASA) changed simultaneously with the degree of Con A agglutinability. This phenomenon disappeared after artificial infection of tumor cells with Friend murine leukemia virus. The result of the quantitative absorption test at 4 degrees C overnight was that 1- and 3-day-old cells did not differ in their absorbing capacities to anti-TASA sera. However, when the absorption test was done at 37 degrees C for 60 minutes, 1-day-old cells had approximately 16 times more absorbing capacity than 3-day-old cells. However, the cytotoxic sensitivity to antiserum against histocompatibility antigen did not change, regardless of the number of days after ip transplantation. Analysis based on the quantitative absorption test revealed no difference in antibody-absorbing capacities between 1- and 3-day-old cells at both 4 degrees C and 37 degrees C. The relationship between Con A agglutinability and cytotoxic sensitivity to anti-TASA serum is discussed from the viewpoint of "lateral receptor mobility" on the cell surface.

Animals↗