germ free life

..The gnotobiotic mouse with bacteria of human origin could be a useful model in studies of bile acid metabolism by human intestinal bacteria in vivo...

..We propose that these proteins represent an evolutionarily primitive form of lectin-mediated innate immunity, and that they reveal intestinal strategies for maintaining symbiotic host-microbial relationships...

..INSeq provides a broadly applicable platform to explore microbial adaptation to the gut and other ecosystems...

..These results reveal that a specific genetic deficiency within a host can profoundly influence the gut commensal microbial community and host physiology...

..The short-term advantages and long-term disadvantages of mutator bacteria could account for their frequency in nature...

..Our aim was to investigate the influence of previous exposure of donor animals to bacterial antigens on colitis development using a transfer model...

..Thus, the lack of intestinal microbiota is accompanied by a state of active IL-10-mediated inflammatory hyporesponsiveness...

..typhimurium infection resembled that of the wild-type pups. Our findings thus reveal a novel role for IFN-gamma in the developmental regulation of antimicrobial responses in the intestine...

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..These data show: firstly, that under SPF conditions, the intestine is seeded with a diverse T-cell population that becomes oligoclonal around the time of weaning; secondly, that GF mice were oligoclonal at each time point...

..This flexible foraging behavior should contribute to ecosystem stability and functional diversity...

..Together, these findings demonstrate that changes in the proliferative status of the intestinal epithelium affects maturation of gammadelta TCR(+) IELs and produces an influx of alphabeta TCR(+) IELs even in the absence of a microflora...

..These findings provide the first evidence from animal studies that reductive acetogens can sustain a functional rumen and replace methanogens as a sink for H(2) in the rumen...

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..Blocking TLR-induced NF-kappaB activity may represent an attractive strategy to treat immune-mediated intestinal inflammation...

..A limited number of intestinal goblet cell-specific proteins have been identified. In this study, we investigate the expression and regulation of RELMbeta, a novel colon-specific gene...

..This study provides evidence that probiotics modulate the oral tolerance response to BLG in mice. The mono-colonization effect is strain-dependant, the best result having been obtained with L. paracasei...

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..However, the field has been hamstrung by the lack of techniques to recombine disrupted genes...

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..These innate immune responses may play a role in the pathogenesis of colitis in SCID adoptive transfer models in mice and possibly in patients with IBD...

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..Their activation status depends on the microbiological status of the dam, and without a commensal flora they remain naive. We propose that these cells regulate antigen responsiveness of the developing mucosal T cell pool...

..We show that unprecedented suicide efficiency can be achieved in soil and seawater after suicide induction by IPTG (isopropyl-beta-D-thiogalactopyranoside). More than 7 orders of magnitude reduction in suicide bacteria was achieved...

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..hepaticus. We conclude that H. hepaticus does not induce or potentiate disease in our IL-10(-/-) mice and therefore is not required to induce colitis in genetically susceptible hosts...

..In addition, splenic APC from GF mice are fully competent to stimulate naïve T-cell proliferation in vitro...

..Absence of PCV2-neutralizing antibodies may be an important factor in the development of an increased virus replication...

..The aim of the study was to identify the known genes directly or indirectly modulated by non-pathologic bacterial flora in the colonic epithelia of germ-free mice...

..We propose that the presence of a microbial flora favors the development of a fully functional Treg population...

..Thus, these bacterias seemed to be important in oral tolerance induction. In addition, the probiotics using these bacteria may be a useful material for the treatment of allergic disorders...

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..Our results indicate that the intestinal microbiota of HFA mice represents a limited sample of bacteria from the human source and are selected by unknown interactions between the host and bacteria...

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..Together, these studies establish gnotobiotic zebrafish as a useful model for dissecting the molecular foundations of host-microbial interactions in the vertebrate digestive tract...

..An expanded repertoire of HTCS proteins with diversified sensor domains may be one reason for B. thetaiotaomicron's success in our intestinal ecosystem...

..These signals acted as reference profiles with which to compare changes in response to gut microbiota manipulation at the tissue level as demonstrated by ingestion of a bacterial probiotic...

..These data demonstrate functionality of the Tn1549-like element and attest that the transfer of the vanB operon between enterococci and human commensal anaerobes occurs in the intestinal environment...

..Interestingly, the VP6 DNA vaccine, although not effective when administered alone, boosted neutralizing and VP4 antibody titers in pigs previously primed with AttHRV, possibly mediated by cross-reactive T helper cells...

..An improved understanding of this hidden organ will reveal secrets that are relevant to human health and to several infectious, inflammatory and neoplastic disease processes...

..cerevisiae tested, strain 905 showed the best characteristics to be used as a probiotic as demonstrated by survival capacity in the gastrointestinal tract and protective effect of animals during experimental infections...

..It is of great concern to decrease these possible negative influences and to discover in the near future the possible means of helping to manipulate positively the gut microbiotia of infants...

..cruzi in gnotobiotic mice. However, the degree of increase in production of cytokines depends on each bacterial component...

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..This protection was not due to the reduction of the population of pathogens in the intestine but was probably related to stimulation of the immune response...

..Together, these findings provide insights about the cellular and molecular targets involved in microbial regulation of intestinal radiosensitivity...

..HFA animals also can be used as models to investigate the interactions between the human intestinal flora, host factors, dietary manipulations, and therapeutics, such as probiotics, prebiotics, and antibiotics...

..coli colonies were susceptible to the given phage cocktail. Apparently, the resident E. coli gut flora is physically or physiologically protected against phage infection...

..Together, these studies establish that hly, rather than bacterial invasion of the lamina propria mediated by InlA, is a dominant determinant of the intensity of the host response to L. monocytogenes infection via the oral route...

..trogontum in the latter. This result, together with the growing number of related reports in the literature, reinforces the possible role of Helicobacter infection in the pathogenesis of hepatobiliary diseases...

..Furthermore, these data support the hypothesis that in each mucosal site, different Ags are responsible for selecting and maintaining the gammadelta TCR over time...

..n. vaccines...

..thetaiotaomicron challenged the mucosal as well as the systemic immune system. Furthermore B. adolescentis obviously suppressed the systemic and mucosal immune reaction against the autochthonous B. thetaiotaomicron...

..These and other studies underscore the importance of understanding precisely how nutrient metabolism serves to establish and sustain symbiotic relationships between mammals and their bacterial partners...

..Disruption of this border alters paracellular permeability and is a key mechanism for the development of enteric infections and inflammatory bowel diseases (IBDs)...

..These results indicate that the infection of GF mice with HT-EHEC is a useful animal model to study the pathogenicity of SLT-producing E. coliand the toxins...

..When beta-galactosidase increased and beta-glucosidase decreased (case of yoghurt, HTY and milk), plasmid transfer occurred at a lower efficiency than in the control group, resulting in lower population levels of transconjugants...

..They also demonstrate that PMN induction is not necessarily associated with clinical symptoms and/or intestinal pathology...

..We propose that acquisition of, or alterations in, commensal bacteria influences intestinal immune homeostasis via direct regulation of the IL-25-IL-23-IL-17 axis...

..These findings provide perspectives about the essential nature of the interactions between resident microorganisms and their hosts...

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..Coordinating this commensal's immediate nutritional requirements with production of a host-derived energy source is consistent with its need to enter and persist within a competitive ecosystem...

..This study shows that EcN is capable of displaying a virulent phenotype in GF C3H/HeJZtm mice. Whether this phenotype is linked to the bacterium's probiotic nature should be the focus of further studies...

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..It also seeks to give an overview of potential regulatory mechanisms involved in the maintenance of intestinal homeostasis, and discusses the clinical implications for inflammatory bowel diseases...

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..Here, data will be presented to show the relationship between intestinal microflora and colon cancers, mainly from our studies, and the mechanism involved will be further discussed...

..Specific pathogen-free (SPF), but not germ-free, interleukin (IL)-2-deficient (IL-2-/-) mice develop colitis. The colitogenicity of commensal bacteria was determined...

..However, most of the total as well as bacteria-specific intestinal IgA was produced by B2 cells. These data suggest that intestinal IgA production induced by commensal bacteria is mainly performed by B2, not B1, cells...

..These findings provide a framework for designing strategies to change the representation and/or properties of M. smithii in the human gut microbiota...

..The stimulation of immunoglobulin production after BF treatment was accompanied by changes in the levels of enterocyte brush-border enzymes; this responsiveness to BF treatment was genetically regulated...

..Therefore, despite similar in vitro probiotic properties, distinct Lactobacillus strains may colonize the gut differently and generate divergent immune responses...

..Both the role of inducible nitric oxide synthase (iNOS) in the development of inflammatory bowel disease (IBD) as well as the molecular details governing its mucosal induction remain unclear...

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..Tylosin in the drinking water favored colonization by transconjugants...

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..longum subsp. longum/infantis can protect against the lethal infections of E. coli O157:H7 by preventing Shiga toxin production in the cecum and/or Shiga toxin transfer from the intestinal lumen to the bloodstream...

..Spontaneous hyper-activation of adaptive immunity against the intestinal microbiota, secondary to innate immune deficiency, may clarify the underlying mechanisms of inflammatory diseases where immune dysfunction is implicated...

..Thus, estimates of in vitro transfer underestimated potential transfer in the digestive tract, and therapeutic doses of cefixime did not increase the selection for transconjugants...

..These findings provide novel insights into the functions of NAbs in mediating host homeostasis and into their roles in health and diseases, such as chronic inflammatory diseases and atherosclerosis...

..Intraperitoneal administration of the synthetic aglycone acetate and the free aglycone appears to be the most effective route for tumor induction and, of these resulting tumors, the most frequent are in the intestinal tract...

..In conclusion, intestinal microbiota determined 8-PN production and exposure after IX intake. Moreover, E. limosum administration increased 8-PN production in low producers, resulting in similar 8-PN production in all rats...

..Immunoselection of bacterial epitope expression may contribute to the remarkable strain-level diversity in this ecosystem...

..This model should encourage investigation of the gut microbiome as a contributor to human metabolic disease and permit discovery of targets for the prevention and treatment of these disorders...

..This system provides a powerful and versatile tool for studying the entire process of human B-lymphocyte development and producing specific human monoclonal antibodies...

..Enteritidis. The parental strains were virulent, inducing severe diarrhoea, dehydration and systemic disease. The cya crp mutant was also highly virulent whereas the aroA strains were attenuated...

..The results suggest that S fimbriae, despite binding to intestinal epithelial cells and mucus, do not contribute to either colonization or translocation in the gnotobiotic rat...

..minor, A. indolicus and A. porcinus strains had low capacity to colonize the upper respiratory tract of gnotobiotic piglets and demonstrated low or no pathogenicity in such animals...

..The model provides convincing evidence that, unlike laboratory variants, clinical isolates colonize, persist and integrate into an already established, albeit reduced, econiche...

..Our findings lead to the testable hypothesis that the relative hypochlorhydria of young children, and conditions that promote reduced acid production in infected adults (e.g. CAG), represent risk factors for spread of H. pylori...

..89; P < 0.001) with the corresponding isotype antibody (IgA) titers in the intestines among all the vaccinated groups, indicating that the IgA antibody titer is probably the most reliable indicator of protection...

..Intensive health monitoring programs, based upon regularly updated recommendations from the microbiological research community, will enable significant reductions in the potential hazards associated with pig-to-human xenotransplantation...

..Because of these mutator alleles' high mutation rates, the initial treatment failure increases the probability of failures in subsequent treatments with other drugs...

..c. Determining if recombinant nonpathogenic bacteria engineered to expressing the dominant E.faecalis epitope can induce T cell - mediated colitis and duodenitis. ..

..Collectively, these data will provide critical insight into pathogenic mechanisms of disease mediated by mammalian circoviruses and will provide key guidance for the future study of human circovirus pathogens. ..

..Restoration and enhancement of immune function may be critical for the effectiveness of anti-Candida vaccines that are now under development. ..

..g., graduate students and postdoctoral fellow). There are ample opportunities to attend seminars, journal clubs and work-in-progress research meetings during which the applicant can become engaged in scientific discussions. ..

..Although only eight positions per year are supported by this grant, 175 postdoctoral trainees are currently being funded by our training program in the laboratories of the 39 participating research mentors. ..

..The study will elucidate the roles of LT, STa and STb in ETEC diarrhea, and determine the key enterotoxins that may pave the way for development of human ETEC vaccines based on enterotoxins as antigens. ..

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..Signatures that can discriminate between tumors that vary in neoplastic potential are particularly important to discern. ..

..This will allow us to hire additional staff to ensure rapid completion of the remaining experiments. With these changes we fully expect to complete these experiments in 2 years. ..

..Such an understanding is critical to our ability to devise more effective therapies against inflammatory disease. ..

..c. Establishment of a website to provide access to the sequence data and clones by the scientific community. ..

..A more complete understanding of the etiopathogenesis of hepatobiliary disease and hepatocellular carcinoma is likely to result in new strategies for treatment and prevention of these important human diseases. ..

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..The work is significant because it discovers the underlying basis for RSV susceptibility preterm and mechanistic approaches to enhance innate immunity. ..

..The studies proposed in this application are aimed at understanding the mechanisms of BspA-induced pathogenesis in periodontal disease and will be vital in developing therapeutic strategies against periodontal diseases in future. ..

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..The work is significant because it discovers the underlying basis for RSV susceptibility preterm and mechanistic approaches to enhance innate immunity. ..

..Thus, the NERCE will greatly improve the preparedness of the United States to resist and respond to attacks by infectious agents, whether their source is bioterrorism or nature. ..

..jejuni invasion is facilitated due to a direct effect of some secreted/excreted product of the worms, and 4) Determine what host cell genes are differentially expressed during C. jejuni invasion. ..

..By identifying the true targets of YopJ, new therapeutic means to treat the plague can be devised, thus reducing the potential impact of a bioterrorist attack. ..

..Perpetuation of the OIMRG and its annual meetings greatly enhances the spirit of collegial interaction/collaboration among investigators with expertise in immunology and microbial pathogenesis as related to oral health and disease. ..

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..In the long term, understanding the basic mechanisms of the BspA-mediated pathogenesis of B. forsythus will be vital in developing intervention strategies against periodontal disease. ..

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..Furthermore, this work will aid in designing novel strategies for strengthening the role of the microflora in enhancing the mucosal barrier. ..

..One of the ultimate goals of this investigation is to understand how polysaccharides activate T cells, which might in turn lead to the design of the interventional strategies for potential new vaccines. ..

..pylori pathogenesis and specifically evaluate the role of regulatory T cells in limiting H. pylori-induced gastric pathology. ..

..Thirdly, the choice of virulence factors ot be tested in vivo will in part be determined by in vitro assays as well as screening H. pylori isogenic mutants in a mouse model, recently developed in our laboratory. ..

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..Most importantly, this information may potentially provide the basis for development of novel therapeutic treatments for IBD in humans. ..

..prior and subsequent to oral vaccination with Helicobacter spp. antigens and mucosal adjuvants, elucidate how these vaccine strategies influence microflora dynamics and impact gut cytokine responses. ..

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..Successful completion of these aims will lead to improved understanding of the pathogenesis of H. pylori associated disease and provide a foundation for development of novel therapies. ..

..Dr. Mansfield has documented success mentoring graduate students and seeks to expand her mentoring of D.V.M.s in mouse pathobiology. ..

..pylori, but will also establish a model in which the roles of other cytokines and mediators can be determined, and host and bacterial interactions can be directly evaluated in vivo. ..

..Inhibitors of smallpox would be essential if vaccine-escape mutants of smallpox were disseminated. Finally compounds that inhibit vaccinia virus would theoretically prevent vaccine (vaccinia) side effects. ..

..The findings from this study will also facilitate an understanding of the potential adjuvant effects of probiotics for development of more effective vaccines against rotavirus and other enteric virus-induced diseases. ..

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