Free-floating aggregate and single cell-initiated biofilms of Staphylococcus aureus

Abstract

Periprosthetic joint infection (PJI) occurring after artificial joint replacement is a major clinical issue requiring multiple surgeries and antibiotic interventions. Staphylococcus aureus is the common bacteria responsible for PJI. Recent in vitro research has shown that staphylococcal strains rapidly form free-floating aggregates in the presence of synovial fluid (SF) with biofilm-like resistance to antimicrobial agents. However, the development of biofilms formed from these aggregates under shear have not been widely investigated. Thus, in this study, we examined the progression of attached biofilms from free-floating aggregates. Biofilms were grown for 24 hours in flow cells on titanium discs after inoculating with either pre-aggregated or single planktonic cells. Image analysis showed no significant difference between the biofilm formed from aggregates vs. the planktonic cells in terms of biomass, surface area, and thickness. Regarding antibiotic susceptibility there was 1 and 2 log reductions in biofilms formed from single cells and aggregates respectively when treated with vancomycin for 24 hours. Thus, this study demonstrates the formation of biofilm from free-floating aggregates follows a similar developmental time-period and shows similar antibiotic tolerance as more traditionally inoculated in vitro flow cell biofilms.

More information

Identifiers

ORCID for Paul Stoodley: orcid.org/0000-0001-6069-273X

Catalogue record

Export record