Micro topographical instruction of bacterial attachment, biofilm formation andin vivohost response

Abstract

The prevention of biofilm development on the surfaces of implanted medical devices is a global challenge for the healthcare sector. Bioinstructive materials that intrinsically prevent bacterial biofilm formation and drive an appropriate host immune response are required to reduce the burden of healthcare associated infections. Although bacterial surface attachment is sensitive to micro- and nano- surface topographies, its exploitation has been limited by the lack of unbiased high throughput biomaterial screens combined with model-based methods capable of generating correlations and predicting generic responses. Consequently, we sought to fill this knowledge gap by using polymer chips (TopoChips) incorporating 2,176 combinatorially generated micro-topographies. Specific surface topographies exerted a profound impact on bacterial pathogen attachment independent of surface chemistry. A strong correlation between local surface landscape, bacterial attachment and biofilm formation was established using machine learning methods to facilitate analysis of specific surface parameters for predicting attachment. In vitro, lead topographies prevented colonization by motile (P. aeruginosa and P. mirabilis) and non-motile ( Staphylococcus aureus and Acinetobacter baumanii bacterial pathogens. In a murine foreign body infection model, specific anti-attachment topographies were shown to be refractory to P. aeruginosa colonization.

Fluid dynamics and cell‐bound Psl polysaccharide allows microplastic capture, aggregation and subsequent sedimentation by Pseudomonas aeruginosa in water

“…Given that PA cells are flagellated and therefore motile, it is an interesting question whether aggregate growth is governed by passive processes such as MP diffusion, and convective flows within the sample or relies on the motility of PA. To assess the importance of bacterium motility, samples were prepared containing MPs and cells from a fliC mutant of PA lacking flagella appendages (Romero et al ., 2022). Aggregate formation was then monitored using LD.…”

“…The size of the agglomerates formed in PA and MPs mixtures was analyzed with a LD particle size analyzer (Beckman‐Coulter LS230). To study the influence of bacterial motility and EPS production on MPs capture, a fliC mutant lacking flagella appendages (Romero et al ., 2022) and a psl operon promoter mutant of PA (Ma et al ., 2007) were used respectively. Wild‐type and mutant PA strains (4.8 × 10 7 cfu ml −1 ) were exposed to 1.4 × 10 8 MPs ml −1 in a 12 ml cell module, and agglomerate formation was analyzed in real‐time over 10 h of incubation at RT and without sample stirring.…”