Biomedical subjects

T Watari

Publications and source records attributed to T Watari.

At least 37 records · Page 2Linked to original sources

PubMed1998

Cloning and mapping of cat (Felis catus) immunoglobulin and T-cell receptor genes.

Molecular cloning and chromosomal mapping of the cat immunoglobulin (Ig) and T-cell receptor (TcR) genes were carried out to provide basic information for genetic analysis of immunologic diseases including leukemias and lymphomas in cats. We cloned two Ig constant genes, IGHM and IGHG and three TcR constant genes, TRAC, TRGC, and TRDC, by polymerase chain reaction (PCR) amplification of cDNA from cat peripheral blood mononuclear cells. For chromosomal mapping of the Ig and TcR loci including the IGK, IGL, and TRB on the cat genome, we performed PCR screening of DNAs from 37 cat x rodent somatic cell hybrids by using specific primers for the given genes. Consequently, three loci for IGH, TRA, and TRD, and two loci for TRB and TRG were found to be syntenic and assigned to cat chromosomes (FCA) B3 and A2, respectively. Further, IGK and IGL loci were mapped on FCA A3 and D3, respectively. These findings support the notion that the genetic linkages between the Ig and TcR genes are extensively conserved between humans and cats.

Amino Acid Sequence↗

PubMed1998

Molecular analysis of chitin synthase 1 (CHS1) gene sequences of Trichophyton mentagrophytes complex and T. rubrum.

Nucleotide sequences of chitin synthase 1 (CHS1) gene of dermatophytes, Arthroderma benhamiae, A. simii, A. vanbreuseghemii, Trichophyton mentagrophytes var. interdigitale (T. interdigitale), and T. rubrum were analyzed for their phylogenetic relationship. About 620-bp genomic DNA fragments of the CHS1 gene were amplified from these dermatophytes by polymerase chain reaction (PCR) and sequenced. The CHS1 nucleotide sequences of these five dermatophytes showed more than 90% similarity between the species. The phylogenetic analysis of their sequences revealed that A. benhamiae, A. simii, A. vanbreuseghemii, and T. rubrum were genetically distinct from one another, but T. interdigitale was genetically very close to A. vanbreuseghemii. On the other hand, a specific restriction endonuclease site of HinfI was present in the CHS1 gene fragment of T. rubrum but not in those of A. benhamiae, A. simii, A. vanbreuseghemii and T. interdigitale. The molecular analysis of CHS1 genes will provide useful information for the identification of these Trichophyton species and the understanding of their evolution.

Animals↗

PubMed1998

Clinicopathological and immunological characteristics of six cats with granular lymphocyte tumors.

Clinical and immunological characteristics were investigated in six cases of feline granular lymphocyte (GL) tumor. The ages of the affected cats were relatively old, ranging from 4 to 13 years of age. Gastrointestinal signs were commonly observed in these cases. Only one of the six GL tumor cases was positive for feline leukemia virus (FeLV) antigen. Phenotypic analysis revealed that the GL tumor cells from all of the six cases lacked the T- or B-cell markers. These GL tumor cells were examined by Southern blot analysis using feline immunoglobulin (Ig) and T-cell receptor (TCR) gene probes. GL tumor cells obtained from two cases were identified as cells of T-cell lineage by the presence of a rearranged TCR beta gene, whereas those from the other four cases were considered to be derived from non-T- non-B-cell lineage because of the absence of rearrangement of these genes. These findings indicated that feline GL tumors can be considered as a specific disease entity in feline lymphomas because the cases examined in this study showed onset at an older age, a low incidence of FeLV infection and frequent involvement of gastrointestinal lesions, which are not found in typical FeLV-associated lymphomas. Although no specific phenotypes was observed by phenotypic analysis, the feline GL tumor cells were divided into two consistent genotypes of T-cell or non-T- non-B-cell lineages.

Abdominal Neoplasms↗

PubMed1998

Genetic heterogeneity of env gene of feline immunodeficiency virus obtained from multiple districts in Japan.

Feline immunodeficiency virus (FIV) infection is widespread in many countries. FIV isolates have been classified into five distinct subtypes, A, B, C, D and E based on their env gene sequences. Several reports indicate that most of the FIVs isolated in Japan belong to subtype B which includes the first Japanese isolate, TM2 strain. To examine the distribution of FIV subtypes in Japan, proviral DNA sequences of the env gene were directly amplified by nested PCR from FIV-infected cats that had been kept in multiple districts throughout Japan. Phylogenetic analysis of the 11 strains showed that four FIV subtypes, A, B, C and D, were present in Japan. Among these subtypes, subtypes B and D were the two most common subtypes in Japan, and they were mainly distributed in the eastern and western parts of Japan, respectively. The present study provides information that is fundamental for development of a vaccine to protect against FIV infection in cats.

Amino Acid Sequence↗

PubMed1998

The use of two immunosuppressive drugs, cyclosporin A and tacrolimus, to inhibit virus replication and apoptosis in cells infected with feline immunodeficiency virus.

An in vitro model of acute and chronic infections with feline immunodeficiency virus (FIV) was used to examine the effect of two immunosuppressive agents, cyclosporin A (CsA) and tacrolimus (also known as FK506), on the inhibition of the replication of the virus and of apoptosis. Both drugs significantly suppressed virus production in a dose-dependent manner in acutely and chronically infected cells. The ability of FK506 to inhibit virus replication was much lower than that of CsA, and was accompanied by marked antiproliferative activity. Treatment of infected cells with either CsA or FK506 did not affect the rise of free intracellular Ca2+ but did protect the cells against apoptosis. Thus, the antiviral activity of CsA and FK506 makes these compounds promising candidates for the development of drugs suitable for the treatment of AIDS.

Animals↗

PubMed1998

The first isolation of Arthroderma benhamiae in Japan.

A clinical isolate of Trichophyton mentagrophytes from rabbit was examined by polymerase chain reaction (PCR) analysis and a mating experiment. The species-specific primers designed from the nucleotide sequences of the chitin synthase 1 (CHS1) gene in the teleomorph of Arthroderma benhamiae amplified a fragment from genomic DNA samples of A. benhamiae and the clinical isolate but not from those of A. simii and A. vanbreuseghemii. On the other hand, the species-specific primers of A. simii and A. vanbreuseghemii did not amplify any fragment from the genomic DNA of the clinical isolates. When the isolate was respectively crossed with (+) or (-) tester strains of A. benhamiae, A. simii and A. vanbreuseghemii, ascospores were produced in the crossing with the A. benhamiae (+) strain. Therefore, the isolate was identified to be A. benhamiae (-), confirming the result of molecular analysis. This is the first report on the isolation of A. benhamiae in Japan.

Animals↗

PubMed1998

Effect of interleukin-12 and interleukin-10 on the virus replication and apoptosis in T-cells infected with feline immunodeficiency virus.

Interleukin-12 (IL-12) is an important cytokine for Th1 response which stimulates the T-cell population to produce cytokines for cellular immunity. Interleukin-10 (IL-10) is a pleiotropic cytokine capable of suppressing cytokine production from macrophages and T-cells and participants in Th2 immune response. The present study was carried out to examine the effect of these cytokines on virus replication and apoptosis in T-cells infected with feline immunodeficiency virus (FIV). Infection of a feline T-lymphoid cell line (Fel-039) resulted in an increase of the reverse transcriptase (RT) activity in the culture supernatant accompanied by cell death from apoptosis. Addition of human recombinant IL-12 significantly inhibited the virus replication and apoptosis in Fel-039 cells in a dose dependent manner. Furthermore, the antiviral activity of IL-12 was associated with the expression of IFN-gamma in the FIV-infected Fel-039 cells. In contrast, human recombinant IL-10 did not show any inhibitory effect on the virus replication and apoptosis in the Fel-039 cells infected with FIV. These results suggest that the inhibitory effect of IL-12 on both virus replication and apoptosis has potential implications for the design of immunotherapy strategies using IL-12 in FIV infection.

Adjuvants, Immunologic↗

PubMed1998

Inhibition of apoptosis and virus replication in feline immunodeficiency virus-infected cells by N-acetylcysteine and ascorbic acid.

Infection of feline immunodeficiency virus (FIV) has been shown to induce apoptosis that might be associated with the lymphocyte depletion in the infected cats. To investigate the inhibitory effect of antioxidants on FIV-induced apoptosis, we examined the effect of N-acetylcysteine (NAC) and ascorbic acid (AA) on apoptosis and virus replication in feline lymphoblastoid (Fel-039) and fibroblastoid (CRFK) cell lines infected with FIV. The treatment with NAC or AA induced a significant inhibition of viral replication and apoptosis in Fel-039 cells and tumor necrosis factor alpha (TNF-alpha)-treated CRFK cells infected with FIV. Both cell lines in the presence of noncytotoxic concentrations of NAC or AA showed in increase of intracellular glutathione (GSH) level, which might protect the cells against oxidative stresses exerted by FIV infection and TNF-alpha treatment. On the basis of these in vitro results, we suggest that antioxidant therapies aimed at restoring depleted GSH level might be effective for inhibition of viral replication and cell death associated with the development of immunodeficiency.

Acetylcysteine↗

PubMed1998

Effect of thromboxane synthetase inhibitor on feline infectious peritonitis in cats.

Two cats with abdominal effusion and anorexia were diagnosed as feline infectious peritonitis (FIP). We tried to evaluate the effect of thromboxane (Tx) synthetase inhibitor, ozagrel hydrochloride, on the progression of symptoms and clinicopathologic data characteristic to FIP. After administration of Tx synthetase inhibitor, improvement of appetite and activity, decreases of peritoneal effusion, reduction of leukocyte number to normal level, and improvement of hyper gamma-globulinemia were found in 2 cats with FIP. These findings suggest that the vasculitis in FIP can be successfully treated with Tx synthetase inhibitor which inhibits platelet aggregation.

Animals↗

PubMed1997

Establishment and characterization of a canine T-lymphoblastoid cell line derived from malignant lymphoma.

A canine lymphoma cell line (CL-1) was established in culture from tumor cells found in the pleural fluid of a 7-year old female Japanese terrier with thymic form lymphoma. The CL-1 cells were positive for CD45 and MHC class II and negative for CD4, CD5, CD8, Thy-1 and B-cell specific antigen and surface immunoglobulin. The CL-1 cells had a rearranged T-cell receptor beta-chain gene and a germ-line form immunoglobulin gene, indicating that the CL-1 cells represented a monoclonally expanded population of canine alpha beta T-cell lineage.

Animals↗

PubMed1997

Cloning and chromosome mapping of the feline genes p21WAF1 and p27Kip1.

For investigation of the relation of cell cycle regulation with tumorigenesis in cats, we carried out molecular cloning of feline p21WAF1 and p27Kip1 cDNAs and chromosomal mapping of these genes on the cat genome. The feline p21WAF1 cDNA clone obtained in this study encoded 164 amino acids (aa) showing 83.5% and 76.8% sequence similarity with those of the human and mouse counterparts, respectively. The cat p27Kip1 cDNA clone isolated here encoded 198 aa, showing sequence similarities of 93.4% and 90.4% with its human and mouse counterparts, respectively. Using a panel of feline x rodent somatic cell hybrids, the feline CDKN1A (p21WAF1) and CDKN1B (p27Kip1) loci were assigned to feline chromosomes B2 and B4, respectively. Southern-blot analyses of 17 feline spontaneous leukemia and lymphoma cases using these cDNAs as probes did not reveal any rearrangements in either the p21WAF1 or the p27Kip1 gene. RT-PCR/SSCP (single strand conformation polymorphism) analysis of p27Kip1 cDNA did not uncover any amino acid substitutions in the 10 feline leukemia and lymphoma cases that were examined.

Amino Acid Sequence↗

PubMed1997

Genomic structure of the bovine mb-1 gene encoding the Ig-alpha subunit of the B cell antigen receptor complex.

The B cell antigen receptor, (BCR) comprises surface immunoglobulin and disulfide-bonded heterodimer of Ig-alpha and Ig-beta chains, which are the products of the mb-1 and B29 genes, respectively. In this study, we describe the isolation and analysis of a 6.2-kb genomic DNA clone containing bovine mb-1 gene encoding Ig-alpha. Sequence data revealed that the bovine mb-1 gene is composed of five exons and four introns, and that its overall structure is very similar to those of murine and human genes. The 5' upstream region of the bovine mb-1 gene contained potential protein binding motifs of transcription factors including EBF, Sp1, NF-kappa B, MUF/Ets-1 and AP 2. As with the murine and human mb-1 genes, the 5' region of the bovine mb-1 gene lacked a TATA box. The present study will be useful for understanding the regulated expression of the bovine mb-1 gene at different stages of development and activation as well as in bovine leukemia virus infection.

Amino Acid Sequence↗

PubMed1997

Molecular cloning and functional expression of equine interleukin-1 receptor antagonist.

Equine interleukin-1 receptor antagonist (IL-1ra) was molecularly cloned to establish a basis for cytokine therapy of acute and chronic inflammatory diseases in the horse. cDNA clones encoding the whole coding sequence of equine IL-1ra were isolated from equine peripheral blood mononuclear cells (PBMC) that had been stimulated with lipopolysaccharide (LPS). The equine IL-1ra cDNA obtained in this study contained an open reading frame encoding 177 amino acid residues. The predicted amino acid sequence of equine IL-1ra shared 75.7, 75.3 and 76.3% similarity with sequences of human, murine and rabbit IL-1ras, respectively. An N-glycosylation site and five cysteine residues conserved in human, murine and rabbit IL-1ras were also found at the corresponding positions in equine IL-1ra. Recombinant glutathione S-transferase (GST)-equine IL-1ra fusion protein produced by Escherichia coli was purified. This protein was shown to inhibit the cytostatic or cytotoxic activity of IL-1 on A375S2 cells, indicating that the equine IL-1ra cDNA obtained in this study encodes biologically active equine IL-1ra.

Amino Acid Sequence↗

PubMed1997

Molecular characteristics of malignant lymphomas in cats naturally infected with feline immunodeficiency virus.

Neoplastic disease, especially malignant lymphomas, are often observed in cats infected with feline immunodeficiency virus (FIV). In order to clarify the characteristics of lymphoma cells and to investigate the pathogenesis in FIV-infected cats, we examined the lymphoma tissues developed in five cats naturally infected with FIV by Southern blot analyses using feline immunoglobulin (Ig), T-cell receptors (TCR) and FIV probes. All of the five cases were serologically positive for anti-FIV antibody and negative for feline leukemia virus antigen. Of these five lymphoma samples, two displayed rearrangement of the Ig heavy chain gene and deletion of the Ig light (kappa) chain gene, indicating that the tumor cells were committed to B-cell development. One tumor sample was identified as a T-cell lymphoma because of the presence of a rearranged TCR beta-chain gene. The other two cases were considered to be non-T non-B cell lymphoma because they did not show any rearrangement of the Ig and TCR genes. Therefore, no consistent tumor type was found in lymphoma cases infected with FIV. Clonal integration of FIV provirus was not detected in any of the five lymphoma samples obtained from FIV-infected cats using Southern blot analysis, although FIV proviral genome was detected in the genomic DNA of all the lymphoma samples by using a polymerase chain reaction (PCR). These results indicated that FIV might not play a direct role in tumorigenesis of lymphoma in cats.

Animals↗

PubMed1997

Phylogenetic analysis of 8 dermatophyte species using chitin synthase 1 gene sequences.

Nucleotide sequences of chitin synthase 1 (CHS1) gene of eight species of dermatophytes, Arthroderma benhamiae, A. fulvum, A. grubyi, A. gypseum, A. incurvatum, A. otae, A. simii and A. vanbreuseghemii were obtained and analysed for their phylogenetic relationship. A 600-bp genomic DNA fragment of the CHS1 gene was amplified from these dermatophytes by polymerase chain reaction (PCR) and sequenced. The CHS1 nucleotide sequences of these eight dermatophyte species showed more than 85% similarity between the species. The phylogenetic analysis of their sequences revealed three clusters, the first cluster consisting of A. benhamiae, A. simii and A. vanbreuseghemii, the second cluster consisting of A. fulvum, A. gypseum and A. incurvatum, and the third cluster consisting of A. grubyi and A. otae. The phylogenetic analysis of CHS1 gene in this study will provide useful information for classification and understanding the evolution of these dermatophyte species.

Arthrodermataceae↗

PubMed1997

Differentiation of Arthroderma spp. by random amplification of polymorphic DNA (RAPD) and Southern hybridization.

To develop the molecular differentiation analysis of dermatophytes, we carried out RAPD and Southern hybridization analyses using genomic DNAs of six Arthroderma species, including A. fulvum, A. grubyi, A. gypseum, A. incurvatum, A. otae and A. racemosum. The RAPD analysis gave different band patterns specific to each of the six Arthroderma fungi. However, minor differences in the banding patterns were observed between the strains of plus (+) and minus (-) mating types of A. gypseum, A. fulvum and A. incurvatum. Southern blot analysis using a probe (1S) obtained from A. grubyi DNA gave specific bands only in the DNA samples of A. grubyi and A. incurvatum. On the other hand, Southern blot analysis using a probe (C3) obtained from A. otae DNA gave specific bands in all six Arthroderma species examined, and the size of the bands were specific to each species. These findings indicate that RAPD and Southern hybridization analyses are useful in the differentiation of these Arthroderma species.

Amino Acid Sequence↗

PubMed1997

A case of feline cryptococcosis treated with itraconazole.

We successfully treated a feline case of cryptococcosis with itraconazole (ITZ) at a lower dosage. The patient was a 2-year-old castrated male Abyssinian cat weighing 4.1 kg and with two masses on the head. Clinical signs were sneezing and nasal discharge. The plasma cryptococcal antigen titer measured by the latex agglutination test was proved to be high (512). The biopsy specimen from the masses disclosed yeast cells which were cultured and identified to be Cryptococcus neoformans. The cat was treated with ITZ 5 mg kg-1 given orally once a day with food. After 4 weeks, treatment of ITZ discontinued, because the cat was clinically normal and the antigen titer was low (128). However, about 7 months later, a subcutaneous nodule was detected on the same area. The nasal discharge appeared again, and the cryptococcal antigen titer was 256. ITZ treatment was continued again at the same dosage for 3 months until the antigen titer was negative (< 8). Four months after discontinuation of ITZ, the cat did not relapse and the antigen titer was in the negative range. No side-effects of ITZ were detected by physical and laboratory examination.

Animals↗

PubMed1997

Structure and function of the long terminal repeats of feline leukemia viruses derived from naturally occurring acute myeloid leukemias in cats.

Long terminal repeats of feline leukemia viruses cloned from feline acute myeloid leukemias frequently contained direct repeats of 40 to 74 bp in the upstream region of the enhancer (URE). The repetitive URE conferred an enhancer function upon gene expression in myeloid cells, suggesting its association with tumorigenic potential in myeloid cells.

Acute Disease↗