Oral microbiology and immunology最新文献

{"title":"Progression of chronic periodontitis can be predicted by the levels of Porphyromonas gingivalis and Treponema denticola in subgingival plaque.","authors":"S J Byrne,&nbsp;S G Dashper,&nbsp;I B Darby,&nbsp;G G Adams,&nbsp;B Hoffmann,&nbsp;E C Reynolds","doi":"10.1111/j.1399-302X.2009.00544.x","DOIUrl":"https://doi.org/10.1111/j.1399-302X.2009.00544.x","url":null,"abstract":"<p><strong>Introduction: </strong>Chronic periodontitis is an inflammatory disease of the supporting tissues of the teeth associated with bacteria. Diagnosis is achieved retrospectively by clinical observation of attachment loss. Predicting disease progression would allow for targeted preventive therapy. The aim of this study was to monitor disease progression in patients on a maintenance program and determine the levels of specific bacteria in subgingival plaque samples and then examine the ability of the clinical parameters of disease and levels of specific bacteria in the plaque samples to predict disease progression.</p><p><strong>Methods: </strong>During a 12-month longitudinal study of 41 subjects, 25 sites in 21 subjects experienced disease progression indicated by at least 2 mm of clinical attachment loss. Real-time polymerase chain reaction was used to determine the levels of Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, Fusobacterium nucleatum, and Prevotella intermedia in subgingival plaque samples.</p><p><strong>Results: </strong>No clinical parameters were able to predict periodontal disease progression. In sites undergoing imminent periodontal disease progression within the next 3 months, significant partial correlations were found between P. gingivalis and T. forsythia (r = 0.55, P < 0.001) and T. denticola and T. forsythia (r = 0.43, P = 0.04). The odds of a site undergoing imminent periodontal disease progression increased with increasing levels of P. gingivalis and T. denticola.</p><p><strong>Conclusion: </strong>Monitoring the proportions of P. gingivalis and T. denticola in subgingival plaque has the potential to help identify sites at significant risk for progression of periodontitis, which would assist in the targeted treatment of disease.</p>","PeriodicalId":19630,"journal":{"name":"Oral microbiology and immunology","volume":"24 6","pages":"469-77"},"PeriodicalIF":0.0,"publicationDate":"2009-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/j.1399-302X.2009.00544.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28061461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scavenger receptor A is expressed by macrophages in response to Porphyromonas gingivalis, and participates in TNF-alpha expression.","authors":"M T Baer, N Huang, F C Gibson","doi":"10.1111/j.1399-302X.2009.00538.x","DOIUrl":"10.1111/j.1399-302X.2009.00538.x","url":null,"abstract":"<p><strong>Introduction: </strong>Porphyromonas gingivalis is a periodontopathic bacterium closely associated with generalized aggressive periodontal disease. Pattern recognition receptors (PRRs) participate in host response to this organism. It is likely that PRRs not previously recognized as part of the host response to P. gingivalis also participate in host response to this organism.</p><p><strong>Methods and results: </strong>Employing qRT-PCR, we observed increased msr1 gene expression at 2, 6, and 24 h of culture with P. gingivalis strain 381. Flow cytometry revealed increased surface expression of SR-A protein by the 24 h time point. Macrophages cultured with an attachment impaired P. gingivalis fimA- mutant (DPG3) expressed intermediate levels of SR-A expression. Heat-killed P. gingivalis stimulated SR-A expression similar to live bacteria, and purified P. gingivalis capsular polysaccharide stimulated macrophage SR-A expression, indicating that live whole organisms are not necessary for SR-A protein expression in macrophage response. As SR-A is known to play a role in lipid uptake by macrophages, we tested the ability of low-density lipoprotein (LDL) to influence the SR-A response of macrophages to P. gingivalis, and observed no effect of LDL on P. gingivalis-elicited SR-A expression. Lastly, we observed that SR-A knockout (SR-A(-/-)) mouse macrophages produced significantly more tumor necrosis factor (TNF)-alpha than wild type mouse macrophages cultured with P. gingivalis.</p><p><strong>Conclusion: </strong>These data identify that SR-A is expressed by macrophages in response to P. gingivalis, and support that this molecule plays a role in TNF-alpha production by macrophages to this organism.</p>","PeriodicalId":19630,"journal":{"name":"Oral microbiology and immunology","volume":"24 6","pages":"456-63"},"PeriodicalIF":0.0,"publicationDate":"2009-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2792726/pdf/nihms160341.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28061459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic diversity and toxic activity of Aggregatibacter actinomycetemcomitans isolates.","authors":"D Kawamoto,&nbsp;E S Ando,&nbsp;P L Longo,&nbsp;A C R Nunes,&nbsp;M Wikström,&nbsp;M P A Mayer","doi":"10.1111/j.1399-302X.2009.00547.x","DOIUrl":"https://doi.org/10.1111/j.1399-302X.2009.00547.x","url":null,"abstract":"<p><strong>Introduction: </strong>Very little is known of the diversity and expression of virulence factors of serotypes of Aggregatibacter actinomycetemcomitans. Toxic activity on Chinese hamster ovary (CHO) cells and cdt and ltx genotyping were evaluated in A. actinomycetemcomitans serotypes.</p><p><strong>Methods: </strong>Forty-one A. actinomycetemcomitans isolates were analysed for CHO cell growth inhibition. Genotyping was performed by polymerase chain reactions specific to the ltx promoter region, serotype-specific and cdt region and by sequencing of cdtB.</p><p><strong>Results: </strong>cdtABC was detected in 40 strains. Analysis of the cdtA upstream region revealed 10 cdt genotypes. Toxicity to CHO cells was detected for 92.7% of the isolates; however, no correlation between the toxic activity and the cdt genotype was detected. Serotype c was more prevalent among Brazilian samples (68.0%). Four serotype b isolates from subjects with aggressive periodontitis were associated with high leukotoxin production and exhibited moderate to strong toxic activity in CHO cells, but were classified in different cdt genotypes. High levels of toxicity in CHO cells were not associated with a particular serotype; 57.1% of serotype a isolates presented low toxicity to CHO cells whereas the highly toxic strains belonged to serotypes b and c. Sequencing of cdtB revealed a single nucleotide polymorphism of amino acid 281 but this was not related to the toxic activity in CHO cells.</p><p><strong>Conclusion: </strong>Differences in prevalence of the low and highly cytotoxic strains among serotypes reinforce the hypothesis that serotype b and c isolates of A. actinomycetemcomitans are more virulent than serotype a strains.</p>","PeriodicalId":19630,"journal":{"name":"Oral microbiology and immunology","volume":"24 6","pages":"493-501"},"PeriodicalIF":0.0,"publicationDate":"2009-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/j.1399-302X.2009.00547.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28438456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Differential virulence and innate immune interactions of Type I and II fimbrial genotypes of Porphyromonas gingivalis.","authors":"M Wang, S Liang, K B Hosur, H Domon, F Yoshimura, A Amano, G Hajishengallis","doi":"10.1111/j.1399-302X.2009.00545.x","DOIUrl":"10.1111/j.1399-302X.2009.00545.x","url":null,"abstract":"<p><strong>Introduction: </strong>The fimA-encoded fimbriae of the periodontal pathogen Porphyromonas gingivalis display genetic diversity. Type I fimbriated P. gingivalis (Pg-I) has been most widely studied at the molecular level, whereas Pg-II is the most frequent isolate from severe periodontitis.</p><p><strong>Methods: </strong>To investigate virulence differences between Types I and II fimbriae, we examined strains 33277 (Pg-I) and OMZ314 (Pg-II), reciprocal swap mutants (i.e. expressing the heterologous fimbrial type), and their respective FimA-deficient derivatives. These organisms were tested in a mouse periodontitis model and in interactions with mouse macrophages, a cell type that plays important roles in chronic infections.</p><p><strong>Results: </strong>Strain 33277 induced significantly more periodontal bone loss than OMZ314 and substitution of Type II fimbriae with Type I in OMZ314 resulted in a more virulent strain than the parent organism. However, the presence of Type II fimbriae was associated with increased proinflammatory and invasive activities in macrophages.</p><p><strong>Conclusion: </strong>The inverse relationship between proinflammatory potential and ability to cause experimental periodontitis may suggest that an aggressive phenotype could provoke a host response that would compromise the persistence of the pathogen.</p>","PeriodicalId":19630,"journal":{"name":"Oral microbiology and immunology","volume":"24 6","pages":"478-84"},"PeriodicalIF":0.0,"publicationDate":"2009-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2883777/pdf/nihms205783.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28438454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of mouse prolactin-inducible protein in saliva on the aggregation of oral bacteria.","authors":"A Nistor,&nbsp;G Bowden,&nbsp;A Blanchard,&nbsp;Y Myal","doi":"10.1111/j.1399-302X.2009.00543.x","DOIUrl":"https://doi.org/10.1111/j.1399-302X.2009.00543.x","url":null,"abstract":"<p><strong>Introduction: </strong>Mouse prolactin-inducible protein (mPIP) is secreted in mouse saliva and has been found to bind oral bacteria, showing the highest affinity for streptococci. Comparisons between the oral flora of mPIP knockout mice and their wild-type controls showed differences in the genera colonizing the two groups of mice. These findings suggested a role for mPIP in the colonization of the mouse oral cavity, possibly modulating the oral flora. In this in vitro study, we focused on the contribution of this protein to aggregation of oral bacteria, a process thought to promote the clearance of bacteria from the oral cavity, and one that could influence the composition of the oral bacterial community.</p><p><strong>Methods: </strong>The aggregation of selected human and mouse oral streptococci was measured spectrophotometrically. The aggregation of oral bacteria by saliva from mPIP knockout mice, which lack mPIP, was compared with that of saliva from wild-type mice.</p><p><strong>Results: </strong>Both wild-type saliva and mPIP knockout mouse saliva induced aggregation of human strain Streptococcus gordonii SK120 and mouse streptococci strains M105/6 and M106/2. Bacterial aggregation induced by the saliva of wild-type mice was significantly higher than the aggregation induced by saliva from mPIP knockout mice for all the bacterial strains.</p><p><strong>Conclusion: </strong>In this study it was confirmed that mPIP plays a role in the aggregation of oral bacteria. The salivary components promoting aggregation of oral bacteria are considered to be part of the oral defense mechanisms so these findings provide insight into a possible function of mPIP in host defense by promoting aggregation of oral bacteria.</p>","PeriodicalId":19630,"journal":{"name":"Oral microbiology and immunology","volume":"24 6","pages":"510-3"},"PeriodicalIF":0.0,"publicationDate":"2009-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/j.1399-302X.2009.00543.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28438459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Helicobacter pylori in the oral cavity is associated with gastroesophageal disease.","authors":"R Morales-Espinosa,&nbsp;A Fernandez-Presas,&nbsp;G Gonzalez-Valencia,&nbsp;S Flores-Hernandez,&nbsp;G Delgado-Sapien,&nbsp;J L Mendez-Sanchez,&nbsp;E Sanchez-Quezada,&nbsp;L Muñoz-Pérez,&nbsp;R Leon-Aguilar,&nbsp;J Hernandez-Guerrero,&nbsp;A Cravioto","doi":"10.1111/j.1399-302X.2009.00541.x","DOIUrl":"https://doi.org/10.1111/j.1399-302X.2009.00541.x","url":null,"abstract":"<p><strong>Background: </strong>In Mexico, more than 80% of the population is infected with Helicobacter pylori. The frequency of H. pylori detection in the oral cavity is unknown, as its relationship with gastroesophageal pathology.</p><p><strong>Aim: </strong>To detect the presence of H. pylori in the oral cavity in Mexican population by PCR and to determine its association with gastroesophageal disease.</p><p><strong>Methods: </strong>Patients were divided into two groups with different clinic conditions from whom gastric biopsy, dental plaque, and saliva samples were taken and analyzed. The first group comprised of hospitalized patients, the majority of whom were diagnosed with gastroesophageal disease, while the second group was selected from a dental clinic (ambulatory population) the majority of whom appeared to be healthy subjects.</p><p><strong>Results: </strong>H. pylori was detected in gastric biopsy, dental plaque and saliva samples by PCR using a set of specific primers for the signal sequence of the vacuolating cytotoxin gene; detection of H. pylori in general was higher in gastric biopsy and dental plaque samples than in saliva samples. Detection of H. pylori in the oral cavity is significantly (P = 0.0001) associated with patients presenting gastroesophageal disease, while healthy subjects and those with other non-gastric disease do not present with H. pylori in their oral cavity.</p><p><strong>Conclusions: </strong>H. pylori detection in the oral cavity is associated to gastroesophageal disease. In addition, it is suggested that all patients presenting gastric symptoms and H. pylori detection in the oral cavity would begin bacterial treatment immediately.</p>","PeriodicalId":19630,"journal":{"name":"Oral microbiology and immunology","volume":"24 6","pages":"464-8"},"PeriodicalIF":0.0,"publicationDate":"2009-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/j.1399-302X.2009.00541.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28061460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cytomegalovirus-infected inflammatory cells in dental periapical lesions.","authors":"M Sabeti,&nbsp;A Daneshmand,&nbsp;J H Simon,&nbsp;J Slots","doi":"10.1111/j.1399-302X.2009.00540.x","DOIUrl":"https://doi.org/10.1111/j.1399-302X.2009.00540.x","url":null,"abstract":"<p><strong>Introduction: </strong>As cytomegalovirus may be etiologically involved in periapical pathosis of endodontic origin, this study aimed to determine the cellular source of periapical cytomegalovirus.</p><p><strong>Methods: </strong>Periapical granulomatous tissue was collected from 15 extracted teeth with symptomatic periapical lesions. Multi-color flow cytometry was used to identify cytomegalovirus-infected cells.</p><p><strong>Results: </strong>Cytomegalovirus infection was identified in 10 of the 15 (67%) study lesions, and in periapical monocytes/macrophages (40% of lesions) and T lymphocytes (54% of lesions), but not in periapical B lymphocytes.</p><p><strong>Conclusion: </strong>This study and previous polymerase chain reaction-based investigations show that cytomegalovirus is a frequent inhabitant of symptomatic periapical lesions.</p>","PeriodicalId":19630,"journal":{"name":"Oral microbiology and immunology","volume":"24 5","pages":"434-6"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/j.1399-302X.2009.00540.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28360656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regulatory roles of beta-catenin and AP-1 on osteoprotegerin production in interleukin-1alpha-stimulated periodontal ligament cells.","authors":"T Suda,&nbsp;T Nagasawa,&nbsp;N Wara-Aswapati,&nbsp;H Kobayashi,&nbsp;K Iwasaki,&nbsp;R Yashiro,&nbsp;D Hormdee,&nbsp;H Nitta,&nbsp;I Ishikawa,&nbsp;Y Izumi","doi":"10.1111/j.1399-302X.2009.00529.x","DOIUrl":"https://doi.org/10.1111/j.1399-302X.2009.00529.x","url":null,"abstract":"<p><strong>Background: </strong>Periodontitis is a chronic inflammatory disease characterized by the enhanced expression of inflammatory mediators leading to alveolar bone resorption. Osteoprotegerin (OPG) plays a suppressive role in cytokine-induced osteoclastogenesis. In osteoblasts, OPG expression is upregulated by beta-catenin but downregulated by the transcription factor activator protein-1 (AP-1; c-fos/c-jun). The purpose of this study was to examine the roles of beta-catenin and AP-1 in interleukin-1alpha (IL-1alpha) -induced OPG production in human gingival fibroblasts (hGFs) and periodontal ligament (PDL) cells.</p><p><strong>Methods: </strong>Expression of c-fos and c-jun messenger RNA was measured by reverse transcription-polymerase chain reaction and OPG production was analysed by enzyme-linked immunosorbent assay. The nuclear AP-1 activity was quantified using an AP-1 microplate assay. The effect of the Wnt canonical pathway on OPG production was evaluated using small interfering (si) RNA for beta-catenin and the effect of AP-1 on OPG production was evaluated using the AP-1 inhibitor curcumin.</p><p><strong>Results: </strong>Levels of c-fos messenger RNA and nuclear AP-1 activity were higher in PDL cells than in hGFs. When stimulated with IL-1alpha, PDL cells had significantly higher c-fos expression and lower OPG production compared with hGFs. The siRNA for beta-catenin suppressed the IL-1alpha-induced OPG production in both PDL cells and hGFs, whereas the AP-1 inhibitor curcumin augmented the IL-1alpha-induced OPG production in PDL cells, but not in hGFs.</p><p><strong>Conclusion: </strong>The present study suggests that beta-catenin enhances IL-1alpha-induced OPG production in both PDL cells and hGFs, whereas AP-1 suppresses IL-1alpha-induced OPG production in PDL cells. Higher expression of c-fos in PDL cells than in hGFs may implicate a role of PDL cells in alveolar bone resorption in periodontitis.</p>","PeriodicalId":19630,"journal":{"name":"Oral microbiology and immunology","volume":"24 5","pages":"384-9"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/j.1399-302X.2009.00529.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28359743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"T-RFLP-based mcrA gene analysis of methanogenic archaea in association with oral infections and evidence of a novel Methanobrevibacter phylotype.","authors":"M E Vianna,&nbsp;G Conrads,&nbsp;B P F A Gomes,&nbsp;H P Horz","doi":"10.1111/j.1399-302X.2009.00539.x","DOIUrl":"https://doi.org/10.1111/j.1399-302X.2009.00539.x","url":null,"abstract":"<p><strong>Introduction: </strong>Increasing evidence suggests a role for methanogenic archaea (methanogens) in human health and disease via syntrophic interactions with bacteria. Here we assessed the prevalence and distribution of methanogens and possible associations with bacteria in oral biofilms.</p><p><strong>Methods: </strong>Forty-four periodontal and 32 endodontic samples from necrotic teeth with radiographic evidence of apical periodontitis were analysed. Terminal restriction fragment length polymorphism analysis based on the mcrA gene, specific to methanogens, was applied. The prevalence and amounts of methanogens in endodontic samples were compared with those of Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, Treponema spp. and Synergistes spp. based on real-time quantitative polymerase chain reactions.</p><p><strong>Results: </strong>Besides dominance of the mcrA gene corresponding to Methanobrevibacter oralis, one mcrA gene type, for which no cultivated member has been reported previously, was identified in five periodontal samples and one endodontic sample. Rates of non-synonymous vs. synonymous nucleotide substitutions suggest that this mcrA gene type codes for a functionally active methyl-coenzyme M reductase. Methanobrevibacter smithii, the prominent methanogen in the human gut system, was not detected. Mean proportions of methanogens were comparable to Synergistes spp. ranging from 0.5 to 1.0% of the total microbial community. Treponema spp. dominated with a mean proportion of 10%, while the mean proportions of the other endodontic pathogens were below 0.1%. A positive association between methanogens and Synergistes spp. was found.</p><p><strong>Conclusion: </strong>Our data provide evidence of a novel, as yet uncultured methanogenic phylotype in association with oral infections, and indicate possible interactions between methanogens and Synergistes spp., the nature of which deserves further investigation.</p>","PeriodicalId":19630,"journal":{"name":"Oral microbiology and immunology","volume":"24 5","pages":"417-22"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/j.1399-302X.2009.00539.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28359749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection of serotype k Streptococcus mutans in Thai subjects.","authors":"J Lapirattanakul,&nbsp;K Nakano,&nbsp;R Nomura,&nbsp;H Nemoto,&nbsp;A Kojima,&nbsp;P Senawongse,&nbsp;R Srisatjaluk,&nbsp;T Ooshima","doi":"10.1111/j.1399-302X.2009.00530.x","DOIUrl":"https://doi.org/10.1111/j.1399-302X.2009.00530.x","url":null,"abstract":"<p><strong>Introduction: </strong>Streptococcus mutans, known to be a pathogen of dental caries as well as bacteremia and infective endocarditis, is classified into four serotypes, c, e, f and k, based on the structures of serotype-specific polysaccharides. Serotype k was recently designated using blood isolates from Japanese subjects and such strains are considered to be virulent in the bloodstream. The purpose of the present study was to analyse the serotype distribution of strains isolated from Thai subjects and determine whether serotype k strains were present.</p><p><strong>Methods: </strong>A total of 250 S. mutans strains were isolated from 50 Thai subjects, and serotypes of all strains were determined. Then, molecular and biological analyses were carried out for serotype k strains.</p><p><strong>Results: </strong>Immunodiffusion and polymerase chain reaction analyses showed that serotype c was the most prevalent (70%), followed by serotypes e (22.8%), f (4.4%) and k (2.8%), which indicated that serotype k S. mutans strains occurred in Thai individuals at a similar rate to that previously reported for Japanese and Finnish populations. Molecular analyses of the seven serotype k strains showed extremely low expression of rgpE, which is related to glucose side-chain formation in serotype-specific rhamnose-glucose polymers, similar to previous reports for those other populations. In addition, analysis of the biological properties of the seven serotype k strains demonstrated low levels of sucrose-dependent adhesion, cellular hydrophobicity, dextran-binding activity and phagocytosis susceptibility by human polymorphonuclear leukocytes, which are characteristics similar to those of serotype k strains previously isolated in Japan.</p><p><strong>Conclusion: </strong>Our results indicate the possibility of a worldwide prevalence of serotype k strains with properties in common with those of previously reported strains.</p>","PeriodicalId":19630,"journal":{"name":"Oral microbiology and immunology","volume":"24 5","pages":"431-3"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/j.1399-302X.2009.00530.x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28360655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}