biofilm
Bacterial InfectionsStaphylococcus aureus Fibronectin Binding Protein A Mediates Biofilm Development and InfectionImplanted medical device-associated infections pose significant health risks, as they are often the result of bacterial biofilm formation. Staphylococcus aureus is a leading cause of biofilm-associated infections which persist due to mechanisms of device surface adhesion, biofilm accumulation, and reprogramming of host innate immune responses. We found that the...
Host-Associated Microbial CommunitiesCooperativity between Stenotrophomonas maltophilia and Pseudomonas aeruginosa during Polymicrobial Airway InfectionsStenotrophomonas maltophilia is a Gram-negative bacterium found ubiquitously in the environment that has historically been regarded as nonpathogenic. S. maltophilia is increasingly observed in patient sputa in cystic fibrosis (CF), and while existing epidemiology indicates that patients with...
Microbial Immunity and Vaccines | SpotlightClearance of Staphylococcus aureus from In Vivo Models of Chronic Infection by Immunization Requires Both Planktonic and Biofilm AntigensStaphylococcus aureus is a causative agent of chronic biofilm-associated infections that are recalcitrant to resolution by the immune system or antibiotics. To combat these infections, an antistaphylococcal, biofilm-specific quadrivalent vaccine against an osteomyelitis model in rabbits has previously been developed and shown to be effective at eliminating biofilm-...
Bacterial InfectionsDirect Microscopic Observation of Human Neutrophil-Staphylococcus aureus Interaction In Vitro Suggests a Potential Mechanism for Initiation of Biofilm Infection on an Implanted Medical DeviceThe ability of human neutrophils to clear newly attached Staphylococcus aureus bacteria from a serum-coated glass surface was examined in vitro using time-lapse confocal scanning laser microscopy. Quantitative image analysis was used to measure the temporal change in bacterial biomass, neutrophil motility, and fraction of the surface area policed by...
Cellular Microbiology: Pathogen-Host Cell Molecular InteractionsDuring the Early Stages of Staphylococcus aureus Biofilm Formation, Induced Neutrophil Extracellular Traps Are Degraded by Autologous ThermonucleaseStaphylococcus aureus extracellular DNA (eDNA) plays a crucial role in the structural stability of biofilms during bacterial colonization; on the contrary, host immune responses can be induced by bacterial eDNA. Previously, we observed production of S. aureus thermonuclease during the early stages...
Bacterial InfectionsIdentification of Novel Bacteriophages with Therapeutic Potential That Target Enterococcus faecalisThe Gram-positive opportunistic pathogen Enterococcus faecalis is frequently responsible for nosocomial infections in humans and represents one of the most common bacteria isolated from recalcitrant endodontic (root canal) infections. E. faecalis is intrinsically resistant to several antibiotics...
Cellular Microbiology: Pathogen-Host Cell Molecular InteractionsThe Autotransporter IcsA Promotes Shigella flexneri Biofilm Formation in the Presence of Bile SaltsShigella flexneri is an intracellular bacterial pathogen that invades epithelial cells in the colonic mucosa, leading to bloody diarrhea. A previous study showed that S. flexneri forms biofilms in the presence of bile salts, through an unknown mechanism.
Cellular Microbiology: Pathogen-Host Cell Molecular InteractionsNovel Assay To Characterize Neutrophil Responses to Oral BiofilmsNeutrophils, the most numerous leukocytes, play an important role in maintaining oral health through interactions with oral microbial biofilms. Both neutrophil hyperactivity and the bacterial subversion of neutrophil responses can cause inflammation-mediated tissue damage like that seen in periodontal disease.
Host Response and InflammationHeterogeneity of Ly6G+ Ly6C+ Myeloid-Derived Suppressor Cell Infiltrates during Staphylococcus aureus Biofilm InfectionMyeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature monocytes and granulocytes. While neutrophils (polymorphonuclear leukocytes [PMNs]) are classically identified as highly differentiated cells specialized for antimicrobial defense, our laboratory has reported minor contributions of PMNs to the immune response during Staphylococcus...
Host-Associated Microbial CommunitiesAutoinducer 2 (AI-2) Production by Nontypeable Haemophilus influenzae 86-028NP Promotes Expression of a Predicted Glycosyltransferase That Is a Determinant of Biofilm Maturation, Prevention of Dispersal, and Persistence In VivoNontypeable Haemophilus influenzae (NTHi) is an extremely common human pathobiont that persists on the airway mucosal surface within biofilm communities, and our previous work has shown that NTHi biofilm maturation is coordinated by the production and uptake of autoinducer 2 (AI-2) quorum signals. To directly test roles for AI-2 in maturation and...