Neither the presence of ica locus, nor in vitro-biofilm formation ability is a crucial parameter for some Staphylococcus epidermidis strains to maintain an infection in a guinea pig tissue cage model

Chokr, Ali; Leterme, Damien; Watier, Denis; Jabbouri, Saı̈d

doi:10.1016/j.micpath.2006.09.001

Cited by 35 publications

(32 citation statements)

References 19 publications

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“…Moreover, an icaADBC mutant did not show reduced viru-lence compared to the wild type in a guinea pig tissue cage model (4,7). These data collectively suggest that PIA-independent mechanisms of biofilm accumulation must exist.…”

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confidence: 80%

“…Future studies will therefore, on one hand, have to address the question of how S. epidermidis biofilm architecture is modulated by the simultaneous presence of PIA, Aap, and Embp. On the other hand, it is important to highlight the finding of epidemiologic surveys and animal studies showing that in specific biofilm-related infections (e.g., prosthetic joint infections), PIA is not essential for S. epidermidis virulence (4,7,8,34). In this study, we showed that Aap and Embp apparently can functionally replace PIA, and it is tempting to speculate that depending on the particular infection site, exhibiting unique local conditions, different intercellular adhesins and biofilm architectures contribute differently to S. epidermidis pathogenesis.…”

Section: Vol 79 2011 S Epidermidis Biofilm-macrophage Interactionsmentioning

confidence: 99%

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Staphylococcus epidermidis Uses Distinct Mechanisms of Biofilm Formation To Interfere with Phagocytosis and Activation of Mouse Macrophage-Like Cells 774A.1

et al. 2011

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Assembly of adherent biofilms is the key mechanism involved in Staphylococcus epidermidis virulence during device-associated infections. Aside from polysaccharide intercellular adhesin (PIA), the accumulation-associated protein Aap and the extracellular matrix binding protein Embp act as intercellular adhesins, mediating S. epidermidis cell aggregation and biofilm accumulation. The aim of this study was to investigate structural features of PIA-, Aap-, and Embp-mediated S. epidermidis biofilms in more detail and to evaluate their specific contributions to biofilm-related S. epidermidis immune escape. PIA-, Embp-, and Aap-mediated biofilms exhibited substantial morphological differences. Basically, PIA synthesis induced formation of macroscopically visible, rough cell clusters, whereas Aap-and Embp-dependent biofilms preferentially displayed a smooth layer of aggregated bacteria. On the microscopic level, PIA was found to form a string-like organized extracellular matrix connecting the bacteria, while Embp produced small deposits of intercellular matrix and Aap was strictly localized to the bacterial surface. Despite marked differences, S. epidermidis strains using PIA, Aap, or Embp for biofilm formation were protected from uptake by J774A.1 macrophages, with similarly efficiencies. In addition, compared to biofilm-negative S. epidermidis strains, isogenic biofilm-forming S. epidermidis induced only a diminished inflammatory J774A.1 macrophage response, leading to significantly (88.2 to 88.7%) reduced NF-B activation and 68.8 to 83% reduced interleukin-1␤ (IL-1␤) production. Mechanical biofilm dispersal partially restored induction of NF-B activation, although bacterial cell surfaces remained decorated with the respective intercellular adhesins. Our results demonstrate that distinct S. epidermidis biofilm morphotypes are similarly effective at protecting S. epidermidis from phagocytic uptake and at counteracting macrophage activation, providing novel insights into mechanisms that could contribute to the chronic and persistent course of biofilm-related S. epidermidis foreign material infections.

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mentioning

confidence: 80%

Section: Vol 79 2011 S Epidermidis Biofilm-macrophage Interactionsmentioning

confidence: 99%

Staphylococcus epidermidis Uses Distinct Mechanisms of Biofilm Formation To Interfere with Phagocytosis and Activation of Mouse Macrophage-Like Cells 774A.1

et al. 2011

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“…Investigations using a mouse foreign body and rat catheter-related models found that PIA-negative strains were less virulent (74,87,90). However, three separate studies employing guinea pig tissue cage models of infection showed no difference in virulence with non-PIA producing strains (91)(92)(93). The type of infection generated in each model can explain in part these differences.…”

Section: Figmentioning

confidence: 97%

Accumulation-Associated Protein Enhances Staphylococcus epidermidis Biofilm Formation under Dynamic Conditions and Is Required for Infection in a Rat Catheter Model

et al. 2015

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Biofilm formation is the primary virulence factor of Staphylococcus epidermidis. S. epidermidis biofilms preferentially form on abiotic surfaces and may contain multiple matrix components, including proteins such as accumulation-associated protein (Aap). Following proteolytic cleavage of the A domain, which has been shown to enhance binding to host cells, B domain homotypic interactions support cell accumulation and biofilm formation. To further define the contribution of Aap to biofilm formation and infection, we constructed an aap allelic replacement mutant and an icaADBC aap double mutant. When subjected to fluid shear, strains deficient in Aap production produced significantly less biofilm than Aap-positive strains. To examine the in vivo relevance of our findings, we modified our previously described rat jugular catheter model and validated the importance of immunosuppression and the presence of a foreign body to the establishment of infection. The use of our allelic replacement mutants in the model revealed a significant decrease in bacterial recovery from the catheter and the blood in the absence of Aap, regardless of the production of polysaccharide intercellular adhesin (PIA), a well-characterized, robust matrix molecule. Complementation of the aap mutant with full-length Aap (containing the A domain), but not the B domain alone, increased initial attachment to microtiter plates, as did in trans expression of the A domain in adhesion-deficient Staphylococcus carnosus. These results demonstrate Aap contributes to S. epidermidis infection, which may in part be due to A domain-mediated attachment to abiotic surfaces.

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“…Finally, the absorbance was measured with a spectrophotometer at 570 nm. This quantity is directly proportional to the number of cells with an intact membrane Ali Chokr has identified and characterized the properties of these strains and deposited it to be enclosed within the collection of microorganisms of Pasteur Institute in 2007 [19][20][21] . The other strains were ATCC that were stored in glycerol stocks at -80°C and used as required.…”

Section: Evaluation Of the Anti-proliferative Activitymentioning

confidence: 99%

Antibacterial, Antioxidant and Antiproliferative Activities of the Hydroalcoholic Extract of the Lebanese Annona Squamosa L. Seeds

Nasser¹,

Majid²,

Falah³

et al. 2017

Int. Res. J. Pharm.

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To determine the chemical composition of the seeds of the Lebanese Annona squamosa L., a phytochemical screening was performed on a water/methanol (v/v) extract. Following that, several quantitative tests were carried out to determine the content of the seeds in the secondary metabolites. Also, the nutritive and medical importance was evaluated in order to realize some biological activities such as antibacterial, antioxidant and anti-proliferative activities. The obtained results showed that the hydroalcoholic extract from the seeds of this fruit contains a variety of primary and secondary metabolites like alkaloids, resins, saponin, phenols, terpenoids, flavonoids, carbohydrates and quinones. In addition, it has a low antioxidant activity and a bacteriostatic activity that is greater than a bactericidal agent. Finally, the seeds' extract presented an anti-proliferative activity that is more effective on HCT-116 colon cells than on HT-29 epithelial cells. Further research studies need to be conducted to confirm the antibacterial, antioxidant and anti-proliferative effects of the seeds found in this fruit.

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Neither the presence of ica locus, nor in vitro-biofilm formation ability is a crucial parameter for some Staphylococcus epidermidis strains to maintain an infection in a guinea pig tissue cage model

Cited by 35 publications

References 19 publications

Staphylococcus epidermidis Uses Distinct Mechanisms of Biofilm Formation To Interfere with Phagocytosis and Activation of Mouse Macrophage-Like Cells 774A.1

Staphylococcus epidermidis Uses Distinct Mechanisms of Biofilm Formation To Interfere with Phagocytosis and Activation of Mouse Macrophage-Like Cells 774A.1

Accumulation-Associated Protein Enhances Staphylococcus epidermidis Biofilm Formation under Dynamic Conditions and Is Required for Infection in a Rat Catheter Model

Antibacterial, Antioxidant and Antiproliferative Activities of the Hydroalcoholic Extract of the Lebanese Annona Squamosa L. Seeds

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