Project description:Neutrophils are critical in the host defense against Staphylococcus aureus, a major human pathogen. However, even in the setting of a robust neutrophil response, S. aureus can cause persistent infection. Here we demonstrate that S. aureus impairs neutrophil function by triggering the production of the anti-inflammatory metabolite, itaconate. The enzyme that synthesizes itaconate, Irg1, is selectively expressed in neutrophils during S. aureus pneumonia. Itaconate inhibits neutrophil glycolysis and oxidative burst, which impairs survival and bacterial killing. In a murine pneumonia model, neutrophil Irg1 expression protects critical lung cell populations from oxidative stress but compromises bacterial clearance. S. aureus is thus able to evade innate immune clearance by targeting neutrophil metabolism and inducing the production of the antiinflammatory metabolite itaconate.
Project description:Neutrophil abscess formation is critical in innate immunity against many pathogens. Here, the mechanism of neutrophil abscess formation was investigated using a mouse model of Staphylococcus aureus cutaneous infection. Gene expression analysis of S. aureus-infected skin revealed that induction of neutrophil recruitment genes was largely dependent upon IL-1beta/IL-1R activation. Unexpectedly, using IL 1beta reporter mice, neutrophils were identified as the primary source of IL-1beta at the site of infection. Furthermore, IL-1beta-producing neutrophils were necessary and sufficient for abscess formation and bacterial clearance. S. aureus-induced IL 1beta production by neutrophils required TLR2, NOD2, FPRs and the ASC/NLRP3 inflammasome. Taken together, IL-1beta and neutrophil abscess formation during an infection are functionally, spatially and temporally linked as a consequence of direct IL-1beta production by neutrophils. Lesional skin biopsies obtained from C57BL/6J WT mice or IL-1R-deficient mice at 4 hours post-infection with Staphylococcus aureus. Uninfected skin biopsies were also collected from WT and IL-1R-deficient mice.
Project description:Staphylococcus aureus is one of the most important pathogens in humans and animals, multiply resistant strains are increasingly widespread, new agents are needed for the treatment of S. aureus. Rhein, a natural plant product, has potential antimicrobial activity against Staphylococcus aureus. We employed Affymetrix Staphylococcus aureus GeneChipsTM arrays to investigate the global transcriptional profiling of Staphylococcus aureus ATCC25923 treated with rhein. Results provided insight into mechanisms involved in rhein - Staphylococcus aureus interactions. Keywords: rhein response
Project description:To study the effect of Radix Paeoniae Rubra decoction on tolerance of Staphylococcus aureus.The effect of Radix Paeoniae Rubra on the resistance of Staphylococcus aureus to oxacillin sodium was studied by millipore dilution method in this experiment.At the same time ,conducted on transcriptome analysis of Staphylococcus aureus related genes in Radix Paeoniae Rubra.And to detect the expression level of related genes of Staphylococcus aureus under the action of Radix Paeoniae Rubra by PCR technology.The tolerance of Staphylococcus aureus was decreased obviously when the concentration of Radix Paeoniae Rubra decoction was above 1mg/ml.The effect of Radix Paeoniae Rubra decoction on the expression of tolerance genes femB,pvL and gluM when the concentration of Radix Paeoniae Rubra decoction was above 4mg/ml.When rhe concentration of Radix Paeoniae Rubra is more than 1mg/ml,it can effectively reduce the resistance of Staphylococcus aureus to oxacillin sodium.The reason may be due to the effect of Radix Paeoniae Rubra on the resistance gene of Staphylococcus aureus.
Project description:Staphylococcus aureus (S. aureus) is an important human and animal pathogen, multiply resistant strains are increasingly widespread, new agents are needed for the treatment of S. aureus. magnolol has potent antimicrobial activity against S. aureus. We employed Affymetrix Staphylococcus aureus GeneChipsTM arrays to investigate the global transcriptional profiling of Staphylococcus aureus ATCC25923 treated with magnolol. Keywords: gene expression array-based, count
Project description:To determine if significant genomic changes are associated with the development of vancomycin intermediate Staphylococcus aureus, genomic DNA microarrays were performed to compare the initial vancomycin susceptible Staphylococcus aureus (VSSA) and a related vancomycin intermediate Staphylococcus aureus (VISA) isolate from five unique patients (five isolate pairs). Keywords: comparative genomic hybridization
Project description:Staphylococcus aureus (S. aureus) is an important human and animal pathogen, multiply resistant strains are increasingly widespread, new agents are needed for the treatment of S. aureus. eugenol, a natural plant product, has potent antimicrobial activity against S. aureus. We employed Affymetrix Staphylococcus aureus GeneChipsTM arrays to investigate the global transcriptional profiling of Staphylococcus aureus ATCC25923 treated with eugenol. Keywords: gene expression array-based, count
Project description:Staphylococcus aureus (S. aureus) is an important human and animal pathogen, multiply resistant strains are increasingly widespread, new agents are needed for the treatment of S. aureus. Cryptotanshinone, a natural plant product, has potent antimicrobial activity against S. aureus. We employed Affymetrix Staphylococcus aureus GeneChipsTM arrays to investigate the global transcriptional profiling of Staphylococcus aureus ATCC25923 treated with cryptotanshinone. Keywords: gene expression array-based, count
Project description:Young adult fer-15;fem-1 Caenorhabditis elegans were infected with Staphylococcus aureus for 8 h to determine the transcriptional host response to Staphylococcus aureus. Analysis of differential gene expression in C. elegans young adults exposed to two different bacteria: E. coli strain OP50 (control), wild-type Staphylococcus aureus RN6390. Samples were analyzed at 8 hours after exposure to the different bacteria. These studies identified C. elegans genes induced by pathogen infection. Keywords: response to pathogen infection, innate immunity, host-pathogen interactions
Project description:Staphylococcus aureus (S. aureus) is an important human and animal pathogen, multiply resistant strains are increasingly widespread, new agents are needed for the treatment of S. aureus. sodium houttuyfonate has potent antimicrobial activity against S. aureus. We employed Affymetrix Staphylococcus aureus GeneChipsTM arrays to investigate the global transcriptional profiling of Staphylococcus aureus ATCC25923 treated with sodium houttuyfonate. Keywords: gene expression array-based, count