Project description:The most clinically relevant risk factor for Clostridioides difficile-associated disease (CDAD) is recent antibiotic treatment. Though most broad-spectrum antibiotics significantly disrupt the structure of the gut microbiota, only particular ones increase CDAD risk, suggesting additional factors might increase the risk from certain antibiotics. Here we show that commensal-independent effects of antibiotics collectively prime an in vitro germ-free human gut for CDAD. We found a marked loss of mucosal barrier and immune function with CDAD-associated antibiotic pretreatment distinct from pretreatment with an antibiotic unassociated with CDAD, which did not reduce innate immune or mucosal barrier functions. Importantly, pretreatment with CDAD-associated antibiotics sensitized mucosal barriers to C. difficile toxin activity in primary cell-derived enteroid monolayers. These data implicate commensal-independent host changes in the increased risk of CDAD with specific antibiotics. Our findings are contrary to the previously held belief that antibiotics allow for CDAD solely through disruption of the microbiome. We anticipate this work to suggest potential avenues of research for host-directed treatment and preventive therapies for CDAD, and to impact human tissue culturing protocols.
Project description:Relative expression levels of mRNAs in chicken cecal epithelia experimentally infected with Eimeria tenella were measured at 4.5 days post-infection. Two weeks old chickens were uninfected (negative control) or were orally inoculated with sporulated oocysts of Eimeria tenella. Cecal epithelia samples were collected from >12 birds in infected or uninfected group at 4.5 d following infections, in which samples from 4 birds were pooled together to form a total 3 biological replicates in each group. Parasite merozoites were also collected from four infected chickens at 5 d after infections. Uninfected control samples, merozoites and infection group samples were selected for RNA extraction and hybridization on Affymetrix microarrays. We used Affymetrix GeneChip chicken genome arrays to detail the chicken cecal epithelia gene expression in the control and E. tenella-infected birds.
Project description:Relative expression levels of mRNAs in chicken cecal epithelia experimentally infected with Eimeria tenella were measured at 4.5 days post-infection. Two weeks old chickens were uninfected (negative control) or were orally inoculated with sporulated oocysts of Eimeria tenella. Cecal epithelia samples were collected from >12 birds in infected or uninfected group at 4.5 d following infections, in which samples from 4 birds were pooled together to form a total 3 biological replicates in each group. Parasite merozoites were also collected from four infected chickens at 5 d after infections. Uninfected control samples, merozoites and infection group samples were selected for RNA extraction and hybridization on Affymetrix microarrays. We used Affymetrix GeneChip chicken genome arrays to detail the chicken cecal epithelia gene expression in the control and E. tenella-infected birds. Infected, uninfected chicken cecal epithelia and merozoites were selected for RNA extraction and hybridization with Affymetrix microarrays. Our goal was to analyze global transcriptome changes in chicken cecal mucous membranes in response to E. tenella infection in vivo. We used infected (T1,T2,T3; three biological replicates) and uninfected (Neg1, Neg2, Neg3; three biological replicates) samples to identify genes that were differentially expressed. Meanwhile, RNA and probes were also prepared from parasite merozoites (Mzt) from infected samples (Mzt) and used as an additional control in microarray hybridization.
Project description:Analysis of Clostridium difficile (Cd) from the cecal contents of germ-free mice or Bacteroides thetaiotaomicron (Bt)-monocolonized mice on a standard, polysaccharide rich diet or polysaccharide deficient diet 5 days after infection. Results identify genes that are involved in the Cd response to diet, in vivo colonization and in interactions with Bt. In vitro transcriptional profiles of Clostridium difficile obtained from cecal contents of germ-free or Bt-monocolonized mice on a standard, polysaccharide rich or polysaccharide deficient diet. 4 samples/group. 2 control genomic DNA samples for Clostridium difficile and 2 reference genomic DNA samples for Bacteroides thetaiotaomicron Please note that 4 control samples (genomic DNA) were used to determine whether the genomic DNA correctly bound to the probes and thus, were not included in data processing (i.e no processed/normalized data).
Project description:Early-life antibiotic exposure perturbs the intestinal microbiota, alters innate intestinal immunity, and accelerates type 1 diabetes development in the NOD mouse model Here we found that maternal cecal microbiota transfer (CMT) to NOD mice with early-life antibiotic perturbation partially rescued the induced T1D acceleration The restoration effects on the intestinal microbiome were substantial and persistent, remediating the antibiotic-depleted diversity, relative abundance of particular taxa, and metabolic pathways CMT also protected against perturbed cecal and serum metabolites and normalized innate and adaptive immune effectors CMT restored patterns of ileal microRNA and histone regulation of gene expression and exon-splicing Based on the analyses of experimental data, we propose an innate intestinal immune network involving CD44, TLR2, and Reg3g, as well as their multiple microRNA and epigenetic regulators that sense intestinal signaling by the gut microbiota This regulation affects downstream immunological tone, leading to protection against the tissue-specific T1D injury