Comparison of in vitro and in vivo systems to study ica-independent Staphylococcus aureus biofilms

• Published in: Journal of microbiological methods Vol. 88; no. 3; pp. 393 - 398
• Main Authors: Ferreira, Fabienne Antunes, Souza, Raquel Rodrigues, Bonelli, Raquel Regina, Américo, Marco Antônio, Fracalanzza, Sérgio Eduardo Longo, Figueiredo, Agnes Marie Sá
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.03.2012; Elsevier
• Subjects: animal models; Animals; antibiotic resistance; bacteremia; Bacteriological methods and techniques used in bacteriology; Bacteriology; Biofilm; Biofilms - growth & development; Biological and medical sciences; blood serum; Environmental Microbiology; fibronectins; Fibronectins - metabolism; Foreign Bodies - microbiology; Fundamental and applied biological sciences. Psychology; Human Experimentation; Humans; Male; methicillin; Methicillin-Resistant Staphylococcus aureus - growth & development; Methicillin-Resistant Staphylococcus aureus - metabolism; Methods; Mice; Mice, Inbred BALB C; Microbiology; MRSA; mutants; pathogenesis; polystyrenes; polyurethanes; prostheses; Spectrum Analysis - methods; Staphylococcus aureus; Statistics as Topic; washing; Biofilm; Methods; Staphylococcus aureus; MRSA; Bacteria; Micrococcales; Micrococcaceae; Method; In vitro
• ISSN: 0167-7012; 1872-8359
• DOI: 10.1016/j.mimet.2012.01.007

The ability of Staphylococcus aureus to form biofilms is considered an important factor in the pathogenesis of central venous catheter-related bacteremia and infections associated with the use of medical prostheses. Different methods have been described for assessing staphylococcal biofilms, but few comparative studies have been attempted to evaluate these techniques; especially related to ica-independent biofilm formation/accumulation. In this study we compared some in vitro and in vivo techniques to evaluate ica-independent biofilms produced by methicillin-resistant S. aureus. We observed that biofilms formed on human fibronectin-covered surfaces were about three times higher than those produced on inert polystyrene surfaces. However, despite the difference in absolute values, a linear correlation was detected between these two models. We also found that biofilms formed on polystyrene or polyurethane surfaces treated with human serum were easily detachable during washing and staining processes. The mouse model of subcutaneous foreign body showed good correlation with the in vitro techniques using either inert polystyrene or solid-phase fibronectin. Thus, our data showed that the microtiter-plate-based spectrophotometric assay is an appropriate method for preliminary biofilm investigations, mainly when a large number of isolates, mutants or systems need to be tested. ► We compared in vitro and in vivo models to study biofilm formation in S. aureus. ► We concluded that microtiter plate assay correlated well with the mouse model. ► We recommend the use of microtiter plate to assess S. aureus biofilms.