Kazuko Takada

Nihon University, Edo, Tōkyō, Japan

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Publications (74)111.15 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Two strains were isolated from the oral cavity samples of healthy elephants. The isolates were gram-positive, catalase-negative, coccus-shaped organisms that were tentatively identified as a streptococcal species based on the results of biochemical tests. Comparative 16S rRNA gene sequence analysis classified these organisms into the genus Streptococcus with Streptococcus criceti ATCC 19642(T) and Streptococcus orisuis NUM 1001(T) as their closest phylogenetic neighbor with 98.2 and 96.9% similarity, respectively. When multilocus sequence analysis using four housekeeping genes, groEL, rpoB, gyrB and sodA, was carried out, percent homology of concatenated sequence of four housekeeping genes from new isolates and S. mutans showed 89.7%. DNA-DNA hybridization experiments suggested that isolates were distinct from S. criceti and other streptococcus species. On the basis of genotypic and phenotypic differences, it is proposed that the novel isolates are classified in the genus Streptococcus as Streptococcus oriloxodontae sp. nov. The type strain of S. oriloxodontae is NUM 2101(T) (=JCM 19285(T) =DSM 27377(T)).
    International journal of systematic and evolutionary microbiology. 08/2014;
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    ABSTRACT: Four Gram-positive, catalase-negative, coccoid-shaped organisms were isolated from elephant oral cavities. The isolates were tentatively identified as a streptococcal species based on the results of biochemical tests. Comparative 16S rRNA gene-sequencing studies confirmed the organisms to be members of the genus Streptococcus. Two isolates were related most closely to Streptococcus salivarius with 96.8% and 93.1% similarity based on the 16S rRNA gene and the RNA polymerase β subunit encoding gene (rpoB) gene, respectively, and to Streptococcus vestibularis with 83.7% similarity based on the 60 kDa heat-shock protein gene (groEL). The other isolates were related most closely to S. vestibularis with 97.0% similarity based on the 16S rRNA gene and to S. salivarius with 93.5% and 82.9% similarity based on the rpoB and groEL genes, respectively. Based on phylogenetic and phenotypic evidence, these isolates are suggested to represent a novel species of the genus Streptococcus. The names proposed for these organisms are Streptococcus loxodontisalivarius sp. nov. (type strain NUM 6304(T)= JCM 19287(T)= DSM 27382(T)) and Streptococcus saliviloxodontae sp. nov. (type strain NUM 6306(T)= JCM 19288(T)= DSM 27513(T)).
    International journal of systematic and evolutionary microbiology 07/2014; · 2.11 Impact Factor
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    ABSTRACT: Corynebacterium matruchotii is a microbial inhabitant in the oral cavity of humans and is associated with the formation of dental calculi. C. matruchotii forms highly specific morphological units, which are referred to as corn-cobs. Although other Corynebacterium species have frequently been isolated from the oral cavity of humans, their distribution has not been reported as extensively. The aim of the present study was to develop a selective medium to isolate the genus Corynebacterium and examine the distribution Corynebacterium species in the oral cavity of humans. The growth recoveries of representative Corynebacterium species on the selective medium were sufficient. Moreover, the growth of other representative oral bacteria was markedly inhibited on the selective medium. The proportion of Corynebacterium species in saliva samples collected from 20 subjects was examined. PCR primers were designed for the oral Corynebacterium species. C. matruchotii and Corynebacterium durum accounted for 0.3 % and 1.5 % of the total cultivable bacteria number on the BHI medium from saliva samples, respectively. The selective medium could distinguish C. matruchotii from C. durum by each colony color using differences in acid production from galactose. The selective medium, designated OCM, was useful for isolating oral Corynebacterium species.
    Journal of microbiological methods. 06/2014;
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    ABSTRACT: Aggregatibacter actinomycetemcomitans is an important pathogen related to aggressively progressive periodontal breakdown in adolescents and adults. The species can be divided into six serotypes (a-f) according to their surface carbohydrate antigens. Recently, a new serotype g of A. actinomycetemcomitans was proposed. The aim of the present study was to sequence the gene cluster associated with the biosynthesis of the serotype g-specific polysaccharide antigen and develop serotype-specific primers for PCR assay to identify serotype g strains of A. actinomycetemcomitans. The serotype-specific polysaccharide (SSPS) gene cluster of the NUM-Aa 4039 strain contained 21 genes in 21,842-bp nucleotides. The similarity of the SSPS gene cluster sequence was 96.7 % compared with that of the serotype e strain. Seventeen serotype g genes showed more than 90 % homology both in nucleotide and amino acids to the serotype e strain. Three additional genes with 1,579 bp in NUM-Aa 4039 were inserted into the corresponding ORF13 of the serotype e strain. The serotype g-specific primers were designed from the insertion region of NUM-Aa 4039. Serotypes of the a-f strains were not amplified by serotype-specific g primers; only NUM-Aa 4039 showed an amplicon band. The NUM-Aa 4039 strain was three genes in the SSPS gene cluster different from those of serotype e strain. The specific primers derived from these different regions are useful for identification and distribution of serotype g strain among A. actinomycetemcomitans from clinical samples.
    Archives of Microbiology 02/2014; · 1.91 Impact Factor
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    ABSTRACT: Objective: Elephants are a close relationship with a Thai. Epidemiological studies can be employed to investigate the microbiota of the elephant oral cavity that can be cultured in vitro in order to provide basic information for the improvement of elephant oral health care. The purpose of this study was to study oral microflora, especially mutans streptococci from the oral cavity of elephants. Method: Oral samples from 6 elephant in zoo were investigated. Samples were collected cotton swab and suspended with buffer and inoculated and cultured on Brain Heart Infusion, Mitis-Salivarius (MS) and selective media for mutans streptococci plates. The bacteria were analyzed morphologically, biochemically, serologically and genetically. The distribution and characterization of the isolates were studied. Result: The average of the cultivable bacteria was 2.86 x 107 CFU/ml. The predominate bacteria were Gram-positive cocci with 64.3% to total cultivable bacteria. Gram-negative cocci and Gram-positive rods were detected approximately 10% each. Gram-negative rods were detected from 2 elephants. All elephants had several kinds of mutans streptococci. Ten morphological different colonies on MS plates were isolated and further characterized. According to biochemical and genetically analysis, 4 isolates classified into S. salivarius group and 6 isolates classified into S. mutans group as new species. Conclusion: These results suggest that the predominate bacteria were Gram-positive cocci and several kind of mutans streptococci were present in elephant oral cavity.
    IADR Asia/Pacific Region (APR) Regional Meeting and Co-Annual Scientific Meeting of IADR Divisions 2013; 08/2013
  • T. OKADA, K. TAKADA, H. SUZUKI, T. IKEMI
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    ABSTRACT: Objective: We are comparing the differences of banding patterns among serotypes of Streptococcus mutans with rep-PCR using Eric primers. The amplicon at 2000bp is common among S. mutans strains, however, some serotype f strains missed the amplicon. The amplicon at 2000bp contained a part of glucan-bainding protein gene which is mediated dextran-dependent aggregation and contribute to cohesive plaque formation. The aim of this study was to compare the differentiation of WIG(water insoluble glucan) synthesis and adherence ability among three serotypes. Method: Each 5 clinical isolates of S. mutans erotypes c and e strains and each 5 serotype f with or without amplicon at 2000bp. (1)WIG synthesis: According to Fukushimas’ method, we modified WIG enzymes from 20 isolates. Enzyme activity was determined with reaction mixture containing 100mM sodium acetate buffer 50mM sucrose. After incubation at 37C for 18 hours, the absorbance of reaction mixture was measured at 340nm. (2) Artificial plaque formation: The adherence ability to a glass surface was measured with modification. After incubation at 37C for 18 hours in a glass test tube(10x75mm) held at an angle of 30°, a percentage of adhered cells to total cells(% adherence) was determined turbidimetrically. Result: (1)WIG synthesis : There were significant differences among four groups. The WIG synthesis ability of serotype f without amplicon at 2000bp were significantly lower than those of others.The type that missed the band at 2000bp were lower than the type of same serotype f that had a band at 2000bp.(2)Artificial plaque formation:On the other hand, there was no significant difference the ability of adherence. Conclusion: These results show that the diversity banding patterns of serotype f might have different ability of glucan synthesis. "The absence of amplicon at 2000bp using ERIC primer in S. mutans may indicate low-cariogenicity."
    IADR Asia/Pacific Region (APR) Regional Meeting and Co-Annual Scientific Meeting of IADR Divisions 2013; 08/2013
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    ABSTRACT: Objective The banding pattern of Streptococcus mutans strains generated using repetitive extragenic palindromic PCR (rep-PCR) with enterobacterial repetitive intergenic consensus (ERIC) primers has been shown previously. In the present study, the sequencing and analysis of gene sequences of the 6 most intense and commonly occurring amplicons from S. mutans serotype c was investigated. Methods The sequences of the amplicons from S. mutans serotype c strain by using rep-PCR with ERIC1R and ERIC2 primers were compared to the whole genome sequence of S. mutans UA159 and NN2025 strains. Results The amplicons were found to contain partial gene sequences coding for proteins such as the hypothetical protein, glucan binding protein A, putative methylated-DNA-protein-cysteine S-methyltransferase, putative d-3-phosphoglycerate dehydrogenase, putative excinuclease ABC (subunit A) and putative GTP-binding protein. The locations of 5 of the 6 amplicons were found to be assembled downstream in the UA159 genome. The coding direction of the amplicons in the NN2025 genome was in reverse orientation relative to that in the UA159 strain, except in the 2170-bp amplicon. Conclusions The repeating sequence elements of ERIC in S. mutans serotype c are located on one side of the genome and have less frequency and similarity compared to those in enterobacteria.
    Journal of Oral Biosciences 08/2013; 55(3):155–158.
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    ABSTRACT: Two tandemly aligned glucosyltransferase (GTF) genes whose gene products are responsible for water-soluble glucan synthesis were isolated from Streptococcus dentirousetti NUM1303 and sequenced. One of the GTF genes of S. dentirousetti consisted of a 4110 bp open reading frame (ORF) that encoded for a 1369 amino acid protein and was revealed to be a S. sobrinus gtfS homolog. The percent similarity of amino acid sequences of the GTF-S from S. dentirousetti compared to those from S. sobrinus was 99%. In addition, a putative gtfT was found in tandem in the downstream region of the S. dentirousetti gtfS. The gtfT of S. dentirousetti consisted of a 4527 bp ORF encoding for 1508 amino acids. The similarity of amino acid sequences of the GTF-T from S. dentirousetti and S. sobrinus was 94%. Phylogenetic analysis based on amino acid sequences from other related streptococcal GTFs suggested that both GTF-S and GTF-T of S. dentirousetti are closely related to S. sobrinus.
    Microbiology and Immunology 05/2013; 57(5):386-90. · 1.55 Impact Factor
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    ABSTRACT: Objectives: Aggregatibacter actinomycetemcomitans organisms are usually isolated from oral cavity in periodontitis. New isolate of A. actinomycetemcomitans from periodontal patient was reported as new serotype g strain previously. The purpose of this study is to perform the sequencing of the gene cluster for the synthesis of serotype g-specific polysaccharide antigen and to design serotype-specific primers for detection of A. actinomycetemcomitans from clinical samples by PCR. Methods: DNA was extracted from bacterial cultures of NUM 4039 serotype g strain using the Genomic DNA purification Kit. The sequences of the gene cluster were determined by direct sequencing of the PCR products amplified from the genomic DNA. Homology searches of the gene cluster from serotype a-f strains were retrieved from the DDBJ databases. Results: The cluster of NUM 4039 serotype g strain consisted of 21 open reading frames in 21,842-bp nucleotides. The similarity of this cluster sequences was 96, 85, 83 and 72% compared with that of A. actinomycetemcomitans serotype e, c, b, and f strains, respectively, but less than 50% with serotype a and d strains. Insertional sequence (about 1500bp) in ORF12 of serotype e cluster was found in serotype g strain. The serotype g-specific primer set was designed in this insertion region. The serotype g-specific band using the primer set by PCR was obtained only from serotype g strains. Conclusions: The synthesis and structure of serotype g-specific polysaccharide of A. actinomycetemcomitans is different from those of serotype e strain. This insertional region is essential to the antigenic specificity of serotype g A. actinomycetemcomitans. This study was supported in part by a Grant-in-Aid for MEXT-SPSRFPU 2008-2012
    IADR/AADR/CADR General Session and Exhibition 2013; 03/2013
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    ABSTRACT: Objective: :We have reported that the banding patterns of serotype f of S.mutans standard strain were different from other serotypes. They missed the band at 2000bp with rep-PCR using Eric primers. The ratio of missing the band at 2000bp was higher than other serotypes including clinical isolates. But we have not examined serotype e clinical isolates from S. mutans. Strain relatedness as determined using genetic fingerprinting might be an important epidemiological tool. The aim of this study was to confirm the differentiation of banding patterns of S. mutans serotype e isolates by rep-PCR using Eric primers. Method: Six S. mutans standerd strains (serotype c, e & f ) and more than 10 clinical isolates(serotype c, e & f ) were used in this study. DNA was extracted by an isolation kit (Qiagen). Rep-PCR was then performed using Eric primers. Post amplification products were separated with electrophoresis through a 2% agarose gel. Followed by staining using ethidium bromide and with photodocumentation. The resulting banding patterns were compared within and between serotype c, e and f isolates. Result: All the bands of standard strains and clinical isolates of serotype c & e and two clinical isolates of serotype f had strongly stained 5 bands. But standard strains and other clinical isolates of serotype f missed the band at 2000bp.There were some exceptions among the clinical isolates of serotype e, but the banding patterns of serotype e were similar with serotype c. Conclusion: These results indicate that our rep-PCR using Eric primers is useful for serotype e clinical isolates. We confirmed that the diversity banding patterns of serotype f were different from other serotypes including clinical isolates. This study was supported in part by a Grant-in-Aid for MEXT-SPSRFPU 2008-2012.
    IADR/AADR/CADR General Session and Exhibition 2013; 03/2013
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    ABSTRACT: Objective: To investigate the phylogenetic affinities of mutans streptococci, a gram-positive streptococci from elephant oral flora was focused and characterized. Method: Oral samples were collected by cotton swab and cultured onto Mitis Salivarius (MS) agar plats. The isolated strains were subjected to biochemical analysis using RapidID32 Strep. The 16S rRNA gene sequence of isolates were determined and analyzed. Water-insoluble glucan (WIG)-synthesizing GTF genes were analyzed by PCR. Result: Three strains, ele-i, ele-U, and ele-3big, isolated from elephant oral cavity capable of glucan-synthesis on MS agar. Among these, ele-i and ele-U were identified with S. salivarius and S. constellatus using RapidID32 strep, respectively, however, ele3big was unable to identify. In 16S rRNA gene sequence analysis, the most closely related strain of ele-i was S. vestibularis, while the most closely related strain of ele-U and ele3big was S. salivarius. The homology of these strains and reference strains showed 97%, respectively. Further, DNA-DNA hybridization analysis was indicated that these three strains were different from each other and reference strains. All ele strains were not possessed mutans streptococcal type WIG-synthesizing GTF genes such as S. mutans gtfB and S. sobrinus gtfI. Conclusion: These results indicated that isolates from elephant were new species based on phenotypic and phylonegetic evidence. This study was supported in part by a Grant-in-Aid for MEXT-SPSRFPU, 2008-12.
    IADR/AADR/CADR General Session and Exhibition 2013; 03/2013
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    ABSTRACT: Objective: Recently, Streptococcus ursoris was isolated and characterized from bear oral cavity. It was supposed that this strain possessed water-insolubel glucan (WIG)-synthesizing GTF gene by PCR. The aim of present investigation was sequence and phylogenetic analyses of GTF gene from S. ursoris. Method: PCR experiment coupled with direct sequencing was carried out to determine of the nucleotide sequence of GTF gene from S. ursoris. Phylogenetic tree was constructed based on deduced amino acid sequences from various streptococcal GTFs. Results: The WIG-synthesizing GTF gene of S. ursoris consisted of a 4,365 bp open reading frame encoding for a 1,455 amino acids, and was revealed to belong to the S. mutans gtfC group. The homology of amino acid sequence of the GTF-C from S. ursoris and S. mutans was 98%. The N-terminal amino acid sequence was responsible for the secretion of GTF-C protein in S. ursoris with high similarity to known other streptococcal GTFs. In addition, two other conserved regions, i.e., N-terminal putative catalytic domain and C-terminal glucan binding domain, were also found in GTF-C of S. ursoris. Phylogenetic analysis of deduced amino acid sequences suggested that S. ursoris and S. mutans GTF-C closely related. Conclusion: It is interested that mutans streptococci isolated from animal oral cavity, for example, pig, fruit bat, and wild bore possessed Streptococcus sobrinus gtfI group of WIG-synthesizing GTF gene, although, different group of WIG-synthesizing GTF gene, S. mutan gtfC, was maintained in S. ursoris. This study was supported in part by a Grant-in-Aid for MEXT-SPSRFPU, 2008-12 and Grant-in-Aid for Young Researchers of Ninon University School of Dentistry at Matsudo 2012.
    IADR/AADR/CADR General Session and Exhibition 2013; 03/2013
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    ABSTRACT: Four Gram-positive, catalase-negative, coccoid-shaped isolates which were obtained from donkey oral cavities formed two distinct clonal groups when characterized by phenotypic and phylogenetic studies. From the results of biochemical tests, the organisms were tentatively identified as a streptococcal species. Comparative 16S rRNA gene sequencing studies confirmed the organisms to be members of the genus Streptococcus. Two of the isolates were related most closely to Streptococcus ursoris with 95.6% similarity based on the 16S rRNA gene and to Streptococcus ratti with 92.0% similarity based on the 60 kDa heat-shock protein gene (groEL). The other two isolates, however, were related to Streptococcus criceti with 95.0% and 89.0% similarities based on the 16S rRNA and groEL genes, respectively. From both phylogenetic and phenotypic evidence, the four isolates formed two distinct clonal groups and are suggested to represent a novel species of the genus Streptococcus. The names proposed for these organisms are Streptococcus orisasini sp. nov. ( type strain NUM 1801(T) = JCM 17942(T) = DMS 25193(T)) and Streptococcus dentasini sp. nov. (type strain NUM 1808(T) = JCM 17943(T) = DMS 25137(T)).
    INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY 01/2013; · 2.11 Impact Factor
  • M. SAITO, N. SHINOZAKI, K. TAKADA
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    ABSTRACT: Objective: A.a is implicated in the etiology of aggressive periodontitis and chronic periodontitis. Lipopolysaccharide (LPS) from A.a is well known as potent inducer pro-inflammatory mediators (such as IL-1beta, IL-6, IL-8 and tumor necrosis factor alpha). The purpose of this study was to examine the cytotoxicity of A. a LPS on leukemia cells (HL60 cells and THP-1 cells) and to determine the inhibition effect of green tea catechins against cytotoxic activity of A.a LPS. Method: A. a LPS and Escherichia coli (E. c) LPS were prepared by hot phenol-water extraction method. The amount of LPS was determined with LPS limulus assay. A. a LPS was mixed with leukemia cells and incubated at 37 °C for 1 hour. The number of leukemia cells was counted to assess viability. Furthermore, anticytotoxic effect of individual catechin components (C, GC, Cg, and EGCg) was investigated. Result: A. a LPS had strong cytotoxic activity on leukemia cells compared with E. c LPS. The cytotoxic activity of A. a LPS was time and dose dependent effect. When each catechin was added to the reaction mixture containing A. a LPS and leukemia cells, LPS-mediated cell lysis was inhibited in the presence of Cg and EGCg. However, presence of C and GC were not able to inhibit the LPS-mediated cell lysis. Conclusion: These results suggested that gallate moiety of green tea catechin was effective for the cytotoxic activity of A. a LPS.
    IADR General Session 2012; 06/2012
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    ABSTRACT: Objective: To investigate the phylogenetic affinities of Streptococcus mutans, Streptococcus macacae from monkey was focused. It was supposed that this strain secreted water-insoluble glucan (WIG) synthease and a part of glucosyltransferase (GTF) gene was possessed by PCR. The aim of present study was sequence and phylogenetic analyses of GTF genes from S. macacae. Method: WIG-synthesizing activity of culture supernatant and sucrose-dependent firm colonization test were carried out. To confirm and determine the WIG-synthesizing GTF gene in S macacae, PCR experiment coupled with direct sequencing was carried out. Phylogenetic tree was constructed based on deduced amino acid sequences from various streptococcal GTFs. Result: S. macacae slightly indicated WIG-synthesizing activity and sucrose-dependent firm colonization ability. The 517-bp fragment of S. mutans gtfB-like gene was amplified from S. macacae by PCR. The homology of corresponded region sequences of the gene from S. macacae and S. mutans was 99%. To attempt the analysis of entire gtfB-like coding region of S. macamae, genome blast search program of NCBI was applied using 3’-terminal conserved region (2 kb) of S. mutas gtfB gene sequence. As a result, three kinds of open reading frames were listed. The corresponded sequences from S. macacae were showed 75, 74, and 76% similarities to the S. mutans gtfB, gtfC, and gtfD, respectively. Phylogenetic analysis of deduced amino acid sequences suggested that S. macacae and S. mutans GTFs closely related, respectively. Conclusion: S. macacae maintained homologue of S. mutans GTF genes, although, the WIG-synthesizing activity was low compared to that of S. mutans suggesting regulation of GTF genes expression were different. This study was supported in part by a Grant-in-Aid for SBFSR 2008-2012 from MEXT.
    IADR General Session 2012; 06/2012
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    ABSTRACT: Streptococcus mutans has been considered the principal etiological agent of dental caries in humans. S. mutans can secrete three kinds of glucosyltransferases (GTFs). One of these, GTF-B, which synthesizes water-insoluble glucans from sucrose, has been considered to be one of the most important factors of cariogenic dental plaque formation. Therefore, determination of whether GTF-B is present in plaque and saliva samples may contribute to the evaluation of individual virulence potential (caries risk). The aim of this study was to develop a feasible enzyme-linked immunosorbent assay (ELISA) for the routine quantification of GTF-B in plaque-derived cultures and clinical samples, and to apply this assay to an epidemiological study. To determine the presence of GTF-B in plaque samples, a sandwich-ELISA was devised, consisting of mouse monoclonal and rabbit polyclonal antibodies against GTF-B and a horseradish peroxidase-conjugated anti-rabbit antibody. The developed ELISA allowed for quantification of the amounts of purified GTF-B with satisfactory sensitivity and specificity; this method was not affected by other components such as plaque and saliva. Plaque samples from healthy volunteers were examined using this ELISA method and microbial analysis to apply the assay to an epidemiological study. A correlation was observed between the amount of extracted GTF-B and S. mutans levels as determined by ELISA and cultivated with Mitis Salivarius Bacitracin agar plates derived from plaque samples, although there were some exceptions. In this regard, this ELISA system has the advantage of estimating both the individual numbers of S. mutans and the productivity of GTF-B, namely, the cariogenic potential of S. mutans simultaneously. These results indicate that this ELISA method is a useful tool for the diagnosis of caries risk.
    Hybridoma (2005) 06/2012; 31(3):176-9. · 0.33 Impact Factor
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    ABSTRACT: A Gram-negative, rod-shaped, non-spore forming and non-motile bacterium, designated strain NUM 1720(T) , was isolated from the oral cavity of bears. Based on 16S rRNA gene sequence similarity, strain NUM 1720(T) was shown to be related to Gibbsiella quercinecans (99.4%). The gyrB and rpoB gene sequences of strain NUM 1720T showed 98.0% and 98.2% similarity with those of G. quercinecans. The DNA-DNA hybridization value of strain NUM 1720(T) with G. quercinecans was 63.8%. The G + C content of the genomic DNA of the isolates was 55.0 mol%. Fatty acid analysis data supported the affiliation of strain NUM 1720(T) to the genus Gibbsiella. The major menaquinone and ubiquinone were MK-8 and Q-8, respectively. Strain NUM 1720(T) can be differed from G. quercinecans by the reactions to acetoin, inositol and D-arabinose. Strain NUM 1720(T) therefore represents a novel species, for which the name Gibbsiella dentisursi sp. nov. is proposed, with type strain NUM 1720(T) (= JCM 17201(T) = DSM 23818(T)).
    Microbiology and Immunology 04/2012; 56(8):506-12. · 1.55 Impact Factor
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    ABSTRACT: Oral immunotherapy is potentially useful for the treatment of allergic diseases. We previously demonstrated that allergen-induced airway inflammation and immunoglobulin E (IgE) production in mice were suppressed by oral administration of high-dose transgenic (Tg) rice seeds (approximately 50 g/kg/day) expressing a T cell epitope of Dermatophagoides pteronyssinus group 1 allergen (Der p 1). However, this amount of Tg rice seeds was not realistic in our daily life. In this study, allergen-induced airway inflammation and IgE production following oral immunotherapy with a realistic (lowest) dose of Tg rice seeds were investigated. Mice orally administered with Tg or non-Tg rice seeds at approximately 5 g/kg/day for 1 week were immunized with recombinant Der p 1, and then challenged with the corresponding allergen. The infiltration of inflammatory cells into the airways and the levels of allergen-specific serum IgE were examined. Low-dose oral administration of Tg rice seeds significantly inhibited the allergen-induced infiltration of eosinophils and lymphocytes into the airways, but allergen-specific IgE synthesis was not changed. Low-dose oral immunotherapy with Tg rice seeds could suppress allergen-induced airway inflammation through mechanisms other than the downregulation of IgE synthesis.
    International Archives of Allergy and Immunology 01/2012; 158 Suppl 1:66-9. · 2.25 Impact Factor
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    ABSTRACT: Celiac disease (CD) is a chronic immune-mediated intestinal inflammatory disorder afflicting genetically susceptible individuals triggered by the consumption of dietary cereals with high gluten content. As with many other organ-specific autoimmune diseases, the dominant tissue-destructive inflammation in CD is T cell-mediated. The proinflammatory cytokine IL-15 that is overexpressed in the intestinal epithelium of CD patients has emerged as a pivotal element that orchestrates intestinal inflammation and T cell-mediated autoimmune tissue destruction. Although no animal model exists that recapitulates the full spectrum of CD pathophysiology, we have previously reported that transgenic mice that overexpress human IL-15 in enterocytes (T3(b)-hlL-15 Tg) display many of the T cell-mediated pathologic features seen in CD. Extending these observations, we now report that T3(b)-hlL-15 Tg mice in addition to recapitulating T cell-mediated effects also display autoantibodies including those against tissue transglutaminase 2 and extensive lamina propria plasmacytosis, all of which are characteristic of CD, thereby reflecting the possibility that locally expressed IL-15 drives both T and B cell pathologic effects seen in CD. More importantly, these findings support the validity and utility of T3(b)-hlL-15 Tg mice as a reasonable model to investigate not only tissue-destructive pathologic processes in CD, but also to explore novel therapeutic modalities for the treatment of this disease.
    Journal of Clinical Immunology 09/2011; 31(6):1038-44. · 3.38 Impact Factor
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    ABSTRACT: This study tested the feasibility of oral immunotherapy for bronchial asthma using a newly developed subunit vaccine in which a fragment (p45-145) of mite allergen (Der p 1) containing immunodominant human and mouse T cell epitopes was encapsulated in endoplasmic reticulum-derived protein bodies of transgenic (Tg) rice seed. Allergen-specific serum immunoglobulin responses, T cell proliferation, Th1/Th2 cytokine production, airway inflammatory cell infiltration, bronchial hyper-responsiveness (BHR) and lung histology were investigated in allergen-immunized and -challenged mice. Prophylactic oral vaccination with the Tg rice seeds clearly reduced the serum levels of allergen-specific IgE and IgG. Allergen-induced CD4(+) T cell proliferation and production of Th2 cytokines in vitro, infiltration of eosinophils, neutrophils and mononuclear cells into the airways and BHR were also inhibited by oral vaccination. The effects of the vaccine were antigen-specific immune response because the levels of specific IgE and IgG in mice immunized with Der f 2 or ovalbumin were not significantly suppressed by oral vaccination with the Der p 1 expressing Tg rice. Thus, the vaccine does not induce nonspecific bystander suppression, which has been a problem with many oral tolerance regimens. These results suggest that our novel vaccine strategy is a promising approach for allergen-specific oral immunotherapy against allergic diseases including bronchial asthma.
    Plant Biotechnology Journal 03/2011; 9(9):982-90. · 6.28 Impact Factor

Publication Stats

525 Citations
111.15 Total Impact Points

Institutions

  • 1997–2014
    • Nihon University
      • • Department of Oral Microbiology
      • • Department of Microbiology
      Edo, Tōkyō, Japan
  • 2009
    • Tokyo Dental College
      Edo, Tōkyō, Japan
  • 1986
    • University of Alabama at Birmingham
      • Department of Microbiology
      Birmingham, Alabama, United States