ABSTRACT: Bacterial species cultivated from multiple sites across the human microbiota (oral, nasal, skin, gastrointestinal tract, reproductive tract).
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: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: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.
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:Background: The skin harbors complex communities of resident microorganisms, yet little is known of their physiological roles and the molecular mechanisms that mediate cutaneous host-microbe interactions. Here, we profiled skin transcriptomes of mice reared in the presence and absence of microbiota to elucidate the range of pathways and functions modulated in the skin by the microbiota. Results: A total of 2820 genes were differentially regulated in response to microbial colonization and were enriched in gene ontology (GO) terms related to the host-immune response and epidermal differentiation. Innate immune response genes and genes involved in cytokine activity were generally upregulated in response to microbiota and included genes encoding toll-like receptors, antimicrobial peptides, the complement cascade, and genes involved in IL-1 family cytokine signaling and homing of T cells. Our results also reveal a role for the microbiota in modulating epidermal differentiation and development, with differential expression of genes in the epidermal differentiation complex (EDC). Genes with correlated co-expression patterns were enriched in binding sites for the transcription factors Klf4, AP-1, and SP-1, all implicated as regulators of epidermal differentiation. Finally, we identified transcriptional signatures of microbial regulation common to both the skin and the gastrointestinal tract. Conclusions: With this foundational approach, we establish a critical resource for understanding the genome-wide implications of microbially mediated gene expression in the skin and emphasize prospective ways in which the microbiome contributes to skin health and disease.
Project description:Immune checkpoint inhibitors (ICIs) targeting PD-1 and CTLA-4 are essential components of the cancer therapeutic armamentarium. The remarkable responses seen with ICIs however, are also accompanied by immune-related adverse events (irAEs). These inflammatory side-effects impact virtually all organ systems, with the most common being the skin and gastrointestinal tract. Here, we establish a mouse model of commensal bacteria-driven skin irAEs and demonstrate that immune checkpoint blockade aberrantly unleashes commensal-specific T cell responses. Such responses caused widespread immune cell infiltration and inflammation throughout the skin, recapitulating the skin irAEs seen in patients treated with ICIs. This skin inflammation was dependent on production of the cytokine IL-17 by commensal-specific T cells, which in turn induced hyperactive responses from macrophages and myeloid cells. Importantly, these responses had long-term consequences, with commensal-specific T cells elicited in the context of ICIs being highly sensitive to re-activation by commensals months later. Together, our results establish a mouse model of skin irAEs and show that immune checkpoint blockade can potentiate aberrant immunity to skin commensals with long-lasting consequences.
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>