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Biomedical subjects

Y Katayose

Publications and source records attributed to Y Katayose.

At least 37 records · Page 2Linked to original sources
PubMed1999

Specific targeting immunotherapy of cancer with bispecific antibodies.

In order to enhance cell mediated cytotoxicity, bispecific antibodies (BsAbs), molecules combining two or more antibodies with different antigenic specificities, have been developed as new agents for immunotherapy. Our recent studies revealed that simultaneous administration of two kinds of BsAbs (anti-tumor x anti-CD3 plus anti-tumor x anti-CD28) together with lymphokine activated killer cells with a T cell phenotype (T-LAK cells) inhibited growth of human xenotransplanted tumors in severe combined immunodeficient (SCID) mice, while single BsAb was without effect. Three kinds of BsAbs (anti-tumor x anti-CD3, anti-tumor x anti-CD28, anti-tumor x anti-CD2) showed the highest cytotoxicity against tumor cells when given simultaneously with T-LAK cells or peripheral blood mononuclear cells in vitro and in vivo. BsAbs can be preserved for immediate application, while cytotoxic T lymphocytes (CTLs) must be made-to-order, and are time-consuming to prepare. Tumor associated antigens, such as MAGE antigens, SART antigens, MUC1 antigen, c-erbB 2 antigen or cancer/testis antigens can be served to target antigens for BsAb production. By conjugation with antibodies to effector cells (anti-CD3, anti-CD28, anti-CD16, anti-CD64, anti-CD89 or anti-CD2), many kinds of BsAbs can be produced to cover most types of cancers from different organs. Therefore this strategy might be ubiquitously applicable to most malignancies.

Animals↗
PubMed1998

Recombinant adenovirus expressing Von Hippel-Lindau-mediated cell cycle arrest is associated with the induction of cyclin-dependent kinase inhibitor p27Kip1.

A recombinant adenovirus containing the Von Hippel-Lindau (VHL) cDNA was constructed (AdVHL) and used to investigate the function of this tumor suppressor gene. Exposure of renal and breast cancer cell lines to AdVHL resulted in high levels of VHL mRNA and protein. AdVHL infection resulted in G1 cell cycle arrest and growth inhibition of renal and breast cancer cell lines. AdVHL-mediated cell cycle arrest was associated with induction of the cyclin-dependent kinase inhibitor (CDKI) p27Kip1 and inhibition of CDK2 and cyclinB1-dependent cdc2 activities. Nuclear run-on analyses and actinomycin D inhibition studies indicate that the induction of p27Kip1 RNA by VHL is mediated at least in part through an increase in p27Kip1 mRNA synthesis. Furthermore, [35S]methionine pulse-chase studies indicate that the increase in p27Kip expression is also regulated through posttranscriptional control mechanisms. These studies support a novel concept that the tumor suppressor gene VHL controls cell cycle progression by regulation of p27Kip1 at both the mRNA and protein levels.

Adenoviridae↗
PubMed1998

Effective adoptive immunotherapy by T-LAK cells retargeted with bacterial superantigen-conjugated antibody to MUC1 in xenografted severe combined immunodeficient mice.

To reinforce cytotoxic activity and the targeting ability of lymphokine-activated killer cells with a T-cell phenotype (T-LAK) for adoptive immunotherapy against human bile duct carcinoma (BDC), staphylococcal enterotoxin A (SEA) was conjugated chemically with MUSE11 monoclonal antibody (MUSE11 mAb), directed to the MUC1 antigen, using N-succinimidyl 3-(2-pyridyldithio) propionate and 2-iminothiolane HCl. Both SEA-conjugated MUSE11 mAb (SEA-MUSE11) and the F(ab')2 of MUSE11 mAb (SEA-F(ab')2) showed significant enhancement of T-LAK cell tumor neutralization for MUC1 positive-target tumor cells, even with a concentration of 0.01 microg/ml at an E:T ratio of 5:1 in vitro. In this in vitro test, MUC1-positive BDC cells were observed to attach to surrounding T-LAK cells in the presence of SEA-MUSE11 or SEA-F(ab')2. Remarkable tumor growth inhibition was observed in BDC-grafted severe combined immunodeficient mice to which 2 x 10(7) T-LAK cells preincubated with 2 microg of SEA-MUSE11 or SEA-F(ab')2, together with recombinant interleukin 2 (500 IU), were administered i.v. for 4 consecutive days, when tumor size was 5 mm in diameter. These results point to a promising adoptive immunotherapy for patients with BDC.

Animals↗
PubMed1998

Expression of Xa1, a bacterial blight-resistance gene in rice, is induced by bacterial inoculation.

The Xa1 gene in rice confers resistance to Japanese race 1 of Xanthomonas oryzae pv. oryzae, the causal pathogen of bacterial blight (BB). We isolated the Xa1 gene by a map-based cloning strategy. The deduced amino acid sequence of the Xa1 gene product contains nucleotide binding sites (NBS) and a new type of leucine-rich repeats (LRR); thus, Xa1 is a member of the NBS-LRR class of plant disease-resistance genes, but quite different from Xa21, another BB-resistance gene isolated from rice. Interestingly, Xa1 gene expression was induced on inoculation with a bacterial pathogen and wound, unlike other isolated resistance genes in plants, which show constitutive expression. The induced expression may be involved in enhancement of resistance against the pathogen.

Amino Acid Sequence↗
PubMed1998

Efficacy of multiple administrations of a recombinant adenovirus expressing wild-type p53 in an immune-competent mouse tumor model.

Infection of Renca cells in vitro with a recombinant adenovirus expressing a marker gene beta-galactosidase resulted in high level of the transgene expression. Renca tumors grown in Balb/C mice were also infectable with this recombinant adenovirus. The transgene expression in the tumors lasted for about 7 days, however, administration of another dose of Ad-beta gal, on day 7 produced beta-galactosidase expression. To investigate the effect of antibodies to adenovirus, animals were injected with multiple doses of adenovirus to produce neutralizing antibodies. To these animals Renca cells were injected and tumors formed. Interestingly, when Ad beta-gal was administered into these tumors, a high level of transgene expression was still observed. We next explored the utility of a recombinant adenovirus expressing p53 (AdWTp53) in the Renca tumor model. Renca cells when exposed to an adenovirus expressing p53 (AdWTp53) produced a high level of p53 protein, a p53-inducible gene p21/WAF1/Cip1 and underwent apoptosis. A single injection of AdWTp53 (10(9) plaque forming units) resulted in significant inhibition of tumor growth. However, multiple administrations (four doses of 2.5 x 10(8) plaque forming units) of AdWTp53 were needed for tumor cures. Mixing uninfected and AdWTp53-infected cells showed a bystander effect of AdWTp53-infected Renca cells. Based on these results we believe that an appropriate dose scheduling of AdWTp53 can be efficacious for cancer gene therapy in immune-competent tumor-bearing animals.

Adenoviridae↗
PubMed1997

Promoting apoptosis: a novel activity associated with the cyclin-dependent kinase inhibitor p27.

p27Kip1, a cyclin-dependent kinase inhibitor, is recognized as a negative regulator of the cell cycle. In this paper, we report that overexpression of p27Kip1 triggers apoptosis in several different human cancer cell lines. Using a recombinant adenoviral vector that expresses p27Kip1 (Adp27), we found that overexpression of p27Kip1 in MDA-MB-231 breast cancer cells induces apoptosis that was seen by a number of different techniques, including flow cytometry and in situ terminal deoxynucleotidyl transferase-mediated nick end labeling, flow cytometric assay for sub-G1 population, and 4',6-diamindino-2-phenylindole staining. Cleavage of poly(ADP-ribose) polymerase and degradation of cyclin B1, events that are known to be associated with apoptosis, were also observed following overexpression of p27Kip1. This is the first report indicating a role for p27Kip1 in induction of apoptosis.

Adenoviridae↗
PubMed1996

MUC1-specific targeting immunotherapy with bispecific antibodies: inhibition of xenografted human bile duct carcinoma growth.

For the purpose of establishing a new adoptive immunotherapy for bile duct carcinoma (BDC), we synthesized two bispecific antibodies (BsAbs), MUC1 x CD3 BsAb constructed with MUSE11 (anti-MUC1 tumor antigen) and OKT-3 (anti-CD3), and MUC1 x CD28 BsAb constructed with MUSE11 and 15E8 (anti-CD28) antibodies. These two BsAbs reacted well with both MUC1-positive target tumor cells and effector lymphokine-activated killer (LAK) cells. Investigation of in vitro cytotoxicity [3-(4,5-dimethylthiazo-2-yl)-2,5-diphenyltetrazolium bromide assay] revealed that the MUC1 x CD3 BsAb could antigen-specifically enhance the cytotoxicity of LAK cells. Addition of the two BsAbs (MUC1 x CD3 BsAb plus MUC1 x CD28 BsAb) in vitro resulted in a 60% cytotoxicity, similar to that obtained with BsAb (MUC1 x CD3) alone. Interleukin 12-induced LAK cells demonstrated far greater cytotoxicity (50%) than their interleukin 2-induced counterparts (LAK cells), and this was also enhanced by the BsAbs. When 2 x 10(7) LAK cells sensitized with both kinds of BsAbs were administered four times i.v. to BDC-grafted severe combined immunodeficient mice (tumor size 5 mm in diameter), inhibition of tumor growth was observed. Thus, BsAb-LAK therapy for control of BDC warrants clinical trials.

Animals↗
PubMed1996

Efficient promoter cassettes for enhanced expression of foreign genes in dicotyledonous and monocotyledonous plants.

A series of chimeric promoters for higher-level expression of foreign genes in plants was constructed as fusions of a gene for beta-glucuronidase (GUS) with the terminator of a gene for nopaline synthase (nos) or of the cauliflower mosaic virus (CaMV) 35S transcript, and the strength of these promoters was assayed in transient and stable expression systems in tobacco and rice. As parts of these promoters, the CaMV 35S core promoter, three different 5'-upstream sequences of the 35S promoter, the first intron of a gene for phaseolin, and a 5'-untranslated sequence (omega sequence) of tobacco mosaic virus were used in various combinations. In tobacco and rice protoplasts, all three fragments of the 35S promoter (-419 to -90, -390 to -90 and -290 to -90, relative to the site of initiation of transcription), the intron, and the omega sequence effectively enhanced GUS activity. Some chimeric promoters allowed levels of GUS activity that were 20- to 70-fold higher than those obtained with the 35S promoter in pBI221. In tobacco protoplasts, the two longer fragments of the 35S promoter were more effective than the shortest fragment. In rice cells, by contrast, the shortest fragment was as effective as the two longer ones. The terminator of the 35S transcript was more effective than that of the nos gene for gene expression. In transgenic tobacco plants, a representative powerful promoter, as compared to the 35S promoter, allowed 10- and 50-fold higher levels of expression on average and at most, respectively, with no clear qualitative differences in tissue- and organ-specific patterns of expression. When the representative promoter was introduced into tobacco with a gene for luciferase, the autofluorescence of detached leaves after a supply of luciferin to petioles was great and was easily detectable by the naked eye in a dark room.

Amino Acid Oxidoreductases↗
PubMed1996

Isolation and genetic characterization of pGKL killer-insensitive mutants (iki) from Saccharomyces cerevisiae.

The linear double stranded DNA plasmid pGKL1 encodes the yeast killer toxin complex (Gunge et al., 1981) of which the killing mechanism is not understood. We isolated and characterized eight mutants in Saccharomyces cerevisiae that were insensitive to both the intracellularly expressed 28-kDa killer subunit and the native killer toxin complex. These mutations (iki1 through iki5) were all recessive, and classified into five complementation groups. The iki2 mutation was mapped to a position near the centromere on chromosome XIII. We developed a novel screening system to isolate the DNA fragments complementing the iki mutations from a Saccharomyces gene library, and isolated three DNA fragments that complement the iki1, iki3, and iki4 mutations, respectively.

Cloning, Molecular↗
PubMed1996

A new in vitro model of specific targeting therapy of cancer: retargeting of PWM-LAK cells with bispecific antibodies greatly enhances cytotoxicity to hepatocellular carcinoma.

For the purpose of establishing a new in vitro model of adoptive immunotherapy, we synthesized two kinds of bispecific antibodies (BsAbs), i.e., (OK x L) BsAbs constructed with both OKT-3 (anti-CD3) and L-7-6 (anti-HCC), and (3G x L) BsAbs constructed with 3-G-8 (anti-CD16) and L-7-6 antibodies. These two BsAbs, having pairs of binding arms on their single molecule, showed similar binding to target cells as the parental monoclonal antibodies (OKT-3, 3-G-8 and L-7-6), when examined with FACS. Newly devised in vitro cytotoxicity tests revealed that LAK or PWM-stimulated LAK (PWM-LAK) cells did not show any significant cytotoxic activity to HCC cells, while both effector cells equally showed greatly enhanced cytotoxicity to HCC even at a low effector/target (0.3) in the presence of BsAbs (OK x L) for the efficient retargeting of the effector cells. Inasmuch as PWM-LAK cells proliferate in vitro 3-5 times faster than LAK cells, adoptive immunotherapy using PWM-LAK cells in combination with (OK x L) BsAbs should be very promising.

Antibodies, Bispecific↗
PubMed1995

Establishment of a new extrahepatic bile duct carcinoma cell line, TFK-1.

A new human extrahepatic bile duct carcinoma cell line (TFK-1) was established from a surgically resected tumor specimen, which was histologically diagnosed as partly papillary adenocarcinoma and partly differentiated tubular adenocarcinoma. The tumor cells cultured in RPMI-1640 medium supplemented with 10% FBS grew as monolayers showing epithelial-like morphology with a population doubling time of 37 hr during exponential growth at passage 40. Chromosome number was distributed in the range of 72 to 76, with a modal number of 73. Tumor markers (CEA, CA19-9, ST-439, DUPAN-2) were negative in culture supernatant and plasma of SCID mice grafted with TFK-1 cells. Though no point mutation at 12 codon of K-ras was detected, expression of c-erb B-2 product and MUC1 antigen was positive. TFK-1 is the third cell line established from extrahepatic bile duct carcinomas in the world literature, and should provide useful information on various aspects of this type of neoplasm.

Adenocarcinoma↗
PubMed1994

Construction of a human B cell line, TKHMY, suitable for production of stable human hybridomas.

In order to produce stable hybridomas for generation of human monoclonal antibodies (HMAbs), an attempt was made to construct a suitable human parental B cell line with double selection markers, the strategy being to produce HMAbs by fusing a parental B cell line with EBV-transformed B cells producing specific antibodies. The resultant TKHMY cell line, constructed by transfecting the Blasticidin S resistant (bsr) gene into the HAT sensitive human B cell line LTR 228 could be used as a fusion partner for very efficient production of human hybridomas. Secretion of IgG monoclonal antibodies to antigens on lung cancer cells by one such hybridoma was very stable, indicating that this TKHMY cell line has practical advantage in the area of antibody production.

Aminohydrolases↗
PubMed1994

The radiologic presentation of Osler-Weber-Rendu disease of the liver.

A case of Osler-Weber-Rendu disease with extensive hepatic arteriovenous fistulation is described in detail. Hemodynamic and imaging data indicated hepatic artery to hepatic vein shunting. Enhanced magnetic resonance imaging demonstrated the existence of arteriovenous fistulas by virtue of simultaneous enhancement of hepatic arteries and veins. Embolization treatment was not indicated because the patient was asymptomatic despite cardiac high output.

Arteriovenous Fistula↗
PubMed1991

Cloning, sequence analysis and transcriptional expression of a ras gene of the edible basidiomycete Lentinus edodes.

In the edible basidiomycete, Lentinus edodes, the presence of a high level of intracellular cyclic AMP (cAMP) is closely related to the onset of fruiting and/or primordium formation. Since a close relationship between intracellular cAMP levels and expression of ras genes was reported for organisms such as Saccharomyces cerevisiae and Dictyostelium discoideum, we have cloned and sequences a ras gene homologue from L. edodes (Le.), and analyzed its expression during development of the fungus. This gene, named Le.ras, has a coding capacity of 217 amino acids (aa) interrupted by six small introns. The deduced Le.Ras protein exhibited the highest homology to the Schizosaccharomyces pombe RAS protein (219 aa): 86% homology in the N-terminal 80-aa sequence and 74% homology in the next 80 aa. The Le.ras gene was transcribed at similar levels during mycelial development in fruiting-body formation, suggesting no direct correlation of Le.ras expression with intracellular cAMP levels in this organism.

Acetylation↗
PubMed1990

The basidiomycete Lentinus edodes linear mitochondrial DNA plasmid contains a segment exhibiting a high autonomously replicating sequence activity in Saccharomyces cerevisiae.

A linear DNA plasmid, designated pLLE1, has been isolated from a mitochondrial fraction of a strain of Lentinus edodes. pLLE1(11.0 kbp) was sensitive to the 3'----5'-acting exonuclease III and resistant to the 5'----3'-acting lambda exonuclease. It showed no homology with mitochondrial and nuclear genomic DNAs of plasmidless strain as well as the pLLE1-harboring host strain of L. edodes. The 1434-bp fragment (sequences) capable of autonomous replication in the yeast Saccharomyces cerevisiae (ARSs) was cloned from pLLE1 DNA with YIp32 (pBR322 containing yeast LEU2 DNA), which displayed a high ARS activity. The cloned 1434-bp fragment was shown to lie near to the end of pLLE1 DNA (nucleotides about 800-2200) and contained three consecutive ARS consensus sequences (A/T)TTTAT(A/G)TTT(A/T) of S. cerevisiae and dispersive eight ARS consensus-like sequences. The subcloned 366-bp fragment containing the three ARSs retained original ARS activity of the 1434-bp fragment.

Base Sequence↗