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M Kinebuchi

Publications and source records attributed to M Kinebuchi.

16 recordsLinked to original sources
PubMed1998

A novel monoclonal antibody against rodent common Thy-1.1 epitope.

Here we report a new anti-rat Thy-1 monoclonal antibody (MAb) 12C5 that recognized a novel epitope on a GPI-anchored Thy-1 antigen. In rat thymocytes, MAb 12C5 reacted with 25 kDa Thy-1 antigen purified with MAb OX7. In rats, MAb 12C5 was expressed on 94% of thymocytes, 46% of spleen cells, 31% of mesenteric lymphnode cells, 76% of bone marrow cells, and 24% of splenic T cells. Furthermore, MAb 12C5 reacted with the hematopoietic cells in Mongolian gerbils, hamsters, and AKR mice (Thy-1.1) as in rats. In AKR mice, almost all bone marrow cells reacted with MAb 12C5. Thus, MAb 12C5 recognized a novel epitope of Thy-1 that was widespread in hematopoietic cells of rats and mice, as well as other rodents.

Animals↗
PubMed1997

Deviated overexpression of TCR-beta, TCR-gamma, CD4, and CD8 on thymic lymphomas induced by 1-propyl-1-nitrosourea: destruction of the allelic exclusion of TCR-beta and expression of functional TCR-betagamma heterodimer on a lymphoma, cFTL53.

Thymic lymphomas (FTLs) induced by the chemical carcinogen 1-propyl-1-nitrosourea (PNU) in F344 rats showed deviated overexpression of TCR-beta, TCR-gamma, CD4, and CD8. Even though most FTLs were in the CD4+ CD8+ stage, all FTLs expressed TCR-beta mRNA with TCR-gamma mRNA, but without TCR-alpha mRNA or TCR-delta mRNA. One of the FTLs, cFTL53, expressed two kinds of TCR-beta mRNA and two kinds of TCR-gamma mRNA, but did not express any mRNA of TCR-alpha or TCR-delta. Both alleles of TCR-beta loci were rearranged on cFTL53. cDNA cloning and sequencing analysis showed that one TCR-gamma mRNA, Vgamma4-Jgamma1-Cgamma1, and both TCR-beta mRNA, Vbeta2-Dbeta2-Jbeta2.1 and Vbeta19-Dbeta2-Jbeta2.1-Cbeta2, on cFTL53 were in the productive form, while the other TCR-gamma mRNA, Vgamma1-Jgamma4-Cgamma4L, was not. Both TCR beta-chains and a TCR gamma-chain were expressed on cFTL53, making a novel set of TCR-betagamma heterodimer. Cross-linking of TCR-betagamma heterodimer on cFTL53 resulted in a calcium flux, indicating that TCR-betagamma works as a signal transduction receptor. Thus, there are four strange phenomena on FTLs; CD4 and CD8 are expressed without TCR-alphabeta or TCR-gammadelta, TCR-beta mRNA and TCR-gamma mRNA were expressed simultaneously without TCR-alpha and TCR-delta mRNA on FTLs, the allelic exclusion of TCR-beta was destroyed in cFTL53, and a novel set of functional TCR-betagamma heterodimer was expressed on cFTL53.

Alleles↗
PubMed1997

RT1.P, rat class Ib genes related to mouse TL: evidence that CD1 molecules but not authentic TL antigens are expressed by rat thymus.

CD1 and TL were once thought to be genetic homologues because of their thymus-specific expression. We investigated their equivalents in the rat to clarify whether their structure and pattern of expression are conserved in rodents. Two rat class Ib genes, containing 3' sequences very similar to mouse TL, were identified and designated RT1.P. Neither of them, however, can encode ordinary class I molecules due to the accumulation of harmful mutations in the 5' regions that are unique to RT1.P, while the 3' TL-like regions still retain protein-coding capacity. Comparison of the structural organization of three types of TL family genes, which include mouse T3/T18-encoding TL antigens, mouse T1/T16, and rat RT1. P1/P2 pseudogenes, revealed the presence of a clear demarcation between the type-specific and TL-specific sequences at intron 3. This finding suggests that recombination plays an important role in creating the TL family genes in rodents. Characteristic features of TL, such as a low level of polymorphism and linkage to the major histocompatibility complex, were also observed in the rat. On the other hand, rat CD1 molecules were expressed at a high level on the surface of thymocytes. Absence of authentic TL antigens and thymic expression of CD1d molecules in the rat suggest the plasticity and conservation of class Ib genes in rodent evolution. Functions of TL may be substituted with CD1 or other class Ib molecules expressed by rat thymus.

Amino Acid Sequence↗
PubMed1993

Structural analysis of the CD3 zeta/eta locus of the rat. Expression of zeta but not eta transcripts by rat T cells.

We analyzed the structure and pattern of expression of rat TCR zeta- and eta-chains to investigate if these components function in activation and development of rat T cells. The rat zeta cDNA contained the complete open reading frame coding for a polypeptide of 164 amino acids and the 5' and 3' noncoding sequences. Comparison of the amino acid sequence to those of mouse and human counterparts revealed a high degree of similarity, more than 85% homology among all three species except for the signal peptide, which was especially high in the cytoplasmic domain including the nucleotide binding site and the possible tyrosine phosphorylation sites. Furthermore, we determined the nucleotide sequences of a rat genomic eta-like sequence located in the 3' region of the rat zeta-gene. Although it showed a high level of nucleotide similarity to mouse and human counterparts, 90.4 and 78.9%, respectively, the deduced polypeptide was very short (only 28 residues) and markedly divergent from the mouse and human eta-specific polypeptides due to frameshift mutations. Transcription of rat zeta was shown to be highly restricted to T cells; abundantly in thymocytes and scarcely in peripheral T cells. Surprisingly, the rat eta transcript could not be detected in any rat tissues so far tested by Northern blot analysis and even by the sensitive reverse transcription-polymerase chain reaction method, whereas it was readily detected in mouse thymus. These findings suggest that the zeta-chain has conserved roles in the TCR assembly and TCR-mediated signaling. However, the eta-chain seems not to be indispensable because of its structural diversity among these three species characterized to date and the apparent lack of eta expression in the rat.

Amino Acid Sequence↗
PubMed1991

A novel cell surface antigen involved in thymocyte and thymic epithelial cell adhesion.

A murine mAb, 7D3, was produced by fusion of spleen cells obtained from mice immunized with a rat thymic epithelial cell line, Tu-D3 and NS/1 myeloma cells. 7D3 antibody reacted with approximately 95% thymocytes, 17% spleen cells, less than 9% of mesenteric lymph node cells and 32% of bone marrow cells of rat origin. 7D3 also reacted with two rat thymic epithelial cell lines but not with a rat fibroblastic cell line. Immunochemical analysis demonstrated that 7D3 antibody recognized a single polypeptide with molecular weight of 80,000 in FTE cells and 80,000 to 96,000 in thymocytes. 7D3 antibody strongly inhibited the thymocyte binding to thymic epithelial cells. In addition, 7D3 antibody inhibited TPA-induced thymocyte aggregation. 7D3 negative rat thymic lymphoma cells bound to 7D3 positive thymic epithelial cells and this binding was inhibited by 7D3 antibody, indicating that a part of thymocyte-thymic epithelial cell binding was mediated by the interaction of 7D3 Ag and undefined ligand to 7D3.

Animals↗
PubMed1990

A monoclonal antibody (8H3) that binds to rat T lineage cells and augments in vitro proliferative responses.

A murine monoclonal antibody, designated 8H3, recognizes a cell surface antigen expressed exclusively on rat T lineage cells. 8H3 antibody immunoprecipitated 180-, 120-, and 90-kD components from rat thymocytes as well as splenic T cells under nonreducing conditions. 8H3 antibody specifically inhibited the binding of thymocytes to fibronectin. Furthermore, binding of rat thymocytes to immobilized synthetic peptide Gly-Arg-Gly-Asp-Ser-Pro-Cys-BSA was inhibited by 8H3 antibody as was Gly-Arg-Gly-Asp-Ser-Pro-Cys, but not by Gly-Arg-Ala-Asp-Ser-Pro-Lys or Gly-Arg-Gly-Glu-Ser-Pro. Crosslinking of 8H3 antigen on double-negative thymocytes and adult thymocytes, as well as splenic T lymphocytes by 8H3 antibody and F(ab')2 fragments of goat antibodies to mouse immunoglobulin, led to an increase in the concentration of cytoplasmic free Ca2+ due to the release of Ca2+ from intracellular stores as well as the influx of Ca2+ from extracellular sources. Expression of interleukin 2 receptor and subsequently cell proliferation was observed upon incubation of thymocytes and splenic T cells with 8H3 antibody. Furthermore, 8H3 antibody induced the proliferation of double-negative thymocytes. These data collectively indicated that a cell surface antigen, 8H3, is involved in not only cell adhesion but also involved in the expression of immature as well as mature thymocytes.

Amino Acid Sequence↗
PubMed1979

Quantitative measurement of intestinal marker enzymes in intestinal metaplasia from human stomach with cancer.

Intestinal metaplasia in human stomach was distinguished macroscopically into sucrase-positive and trehalase-positive areas, and sucrase-positive and trehalase-negative areas, by location of these disaccharidase activities with TES-Tape. After location of these two areas with TES-Tape, tissues were taken from them for colorimetric measurement of sucrase, trehalase, leucine aminopeptidase (LAP), and alkaline phosphatase (ALP). Results showed that in the mucosa from sucrase-positive and trehalase-negative areas, trehalase activity was not detectable and the activities of sucrase, LAP, and ALP were lower than in sucrase-positive and trehalase-positive areas.

Alkaline Phosphatase↗