ABSTRACT: Bacterial species cultivated from multiple sites across the human microbiota (oral, nasal, skin, gastrointestinal tract, reproductive tract).
Project description:Background Alterations of the gut microbiome have been linked to multiple chronic diseases. However, the drivers of such changes remain largely unknown. The oral cavity acts as a major route of exposure to exogenous factors including pathogens, and processes therein may affect the communities in the subsequent compartments of the gastrointestinal tract. Here, we perform strain-resolved, integrated multi-omic analyses of saliva and stool samples collected from eight families with multiple cases of type 1 diabetes mellitus (T1DM). Results We identified distinct oral microbiota mostly reflecting competition between streptococcal species. More specifically, we found a decreased abundance of the commensal Streptococcus salivarius in the oral cavity of T1DM individuals, which is linked to its apparent competition with the pathobiont Streptococcus mutans. The decrease in S. salivarius in the oral cavity was also associated with its decrease in the gut as well as higher abundances in facultative anaerobes including Enterobacteria. In addition, we found evidence of gut inflammation in T1DM as reflected in the expression profiles of the Enterobacteria as well as in the human gut proteome. Finally, we were able to follow transmitted strain-variants from the oral cavity to the gut at the metagenomic, metatranscriptomic and metaproteomic levels, highlighting not only the transfer, but also the activity of the transmitted taxa along the gastrointestinal tract. Conclusions Alterations of the oral microbiome in the context of T1DM impact the microbial communities in the lower gut, in particular through the reduction of “oral-to-gut” transfer of Streptococcus salivarius. Our results indicate that the observed oral-cavity-driven gut microbiome changes may contribute towards the inflammatory processes involved in T1DM. Through the integration of multi-omic analyses, we resolve strain-variant “mouth-to-gut” transfer in a disease context.
Project description:<p>This first clinical study of the Human Microbiome Project (HMP) addresses whether individuals share a core human microbiome. It involves broad determination of the microbiota found in five anatomical sites: the oral cavity, skin, nasal cavity, gastrointestinal tract and vagina. This study will enroll approximately 300 healthy male and female adults, 18-40 years old, from two geographic regions of the US: Houston, TX and St. Louis, MO. The participation of healthy individuals will create a baseline for discovery of the core microbiota typically found in various areas of the human body. The information from this initial study can then be used to help assess the changes in the complement of microbiota found on or within diseased individuals.</p>
Project description:Asymptomatic colonization of the upper respiratory tract is a common trait of the two exclusive human pathogens, Neisseria gonorrhoeae and Neisseria meningitidis. In vivo models of pathogenic neisserial infections are heterologous systems that permit short-term persistence but do not fully recapitulate infections in humans. Studying Neisseria musculi (Nmus), an oral commensal, in laboratory mice allows investigation of Neisseria-host interactions that avoids host restriction barriers. Nmus produces smooth and rough morphotypes on solid media. We compared the in vitro phenotypes, biofilm transcriptomes, and in vivo colonization patterns and burdens of the Nmus morphotypes. We observed that the two morphotypes differ in biofilm formation, aggregation, pilin production, and transformation frequency in vitro. These phenotypes strongly correlated with differential expression of a set of genes in the Nmus biofilms including those that encoded factors for bacterial attachment. In vivo, the smooth morphotype stably colonized the oral cavities of all inoculated A/J and C57BL/6J mice at higher burdens compared to the rough. Following nasal inoculations, we detected transient Nmus nasal colonization. The smooth morphotype was able to reach higher burdens more quickly in the nasal cavity and on oral swabs following dissemination to the oral cavity. Gut colonization burdens fluctuated over time. Interestingly, both morphotypes colonized the oral cavities of A/Js at higher magnitudes than in C57BL/6Js. Collectively, our results demonstrate that colonization by Nmus can be affected by various factors including Nmus morphotypes, inoculation routes, anatomical niches, and host backgrounds. The Nmus-mouse model can use variable morphotype-host combinations to study the dynamics of neisserial asymptomatic colonization and persistence in multiple extragenital niches.
Project description:Keratinocytes are the major constituent of epithelial cells at mucosal surfaces and skin, which cover organs, internal cavities and the body. Traditionally, keratinocytes have been considered as an inert component of the multilayered epithelium to protect the subepithelial compartments from the pathogenic microorganisms, toxic stimuli and physical trauma. However, accumulated researches of the airway, gastrointestinal tract and skin have demonstrated that keratinocytes function in the development of the immune system, promotion of pathologic inflammation and even impose diverse decisions on immune cells. We used microarrays to detail the global gene expression of oral keratinocyte during oral adaptive immune response. Oral keratinocyte were collected at three time points (control, 48h and 96h) in oral adaptive immune response for RNA extraction and hybridization on Affymetrix microarrays
Project description:<p>This first clinical study of the Human Microbiome Project (HMP) addresses whether individuals share a core human microbiome. It involves broad determination of the microbiota found in five anatomical sites: the oral cavity, skin, nasal cavity, gastrointestinal tract and vagina. This study will enroll approximately 300 healthy male and female adults, 18-40 years old, from two geographic regions of the US: Houston, TX and St. Louis, MO. The participation of healthy individuals will create a baseline for discovery of the core microbiota typically found in various areas of the human body. The information from this initial study can then be used to help assess the changes in the complement of microbiota found on or within diseased individuals.</p>
Project description:Background: Alternative polyadenylation (APA) is emerging as a widespread mechanism of gene regulation. The usage of APA sites allows a single gene to encode multiple mRNA transcripts with different 3'-untranslated region (3'UTR) lengths. Many disease processes reflect the importance of the regulation of APA site switching. The objective of this study was to explore the profiling of tandem APA sites in nasal polyps compared with nasal uncinate process mucosa. Methods: Sequencing of APA sites (SAPAS) based on second-generation sequencing technology was undertaken to investigate the use of tandem APA sites and identify gene expression patterns in samples from the nasal polyps and nasal uncinate process mucosa of two patients with chronic rhinosinusitis with nasal polyps. The findings of the SAPAS analysis were validated via quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Results: First, the results showed a switching of 3'UTR lengths in nasal polyps compared with nasal uncinate process mucosa. From the two patients, 105 overlapping genes in the nasal polyps were switched to distal poly(A) sites, and 90 such genes were switched to proximal poly(A) sites. Several Gene Ontology terms were enriched in the list of genes with switched APA sites, including transcription regulation, cell cycle, apoptosis, and metabolism. Second, we detected genes that showed differential expression with at least a 3-fold difference between nasal polyp tissue and nasal uncinate process mucosa. Between the two sample types, 627 genes exhibited differential expression. The qRT-PCR results confirmed our SAPAS results. Conclusion: APA site-switching events of 3'UTRs are prevalent in nasal polyp tissue, and the regulation of gene expression mediated by APA may play an important role in the formation and persistence of nasal polyps. Our results may provide new insights into the possible pathophysiologic processes involved in nasal polyps. Investigate the use of tandem APA sites of 3'ends of mRNAs using second-generation sequencing technology.