Impact of Pseudomonas aeruginosa quorum sensing on cellular wound healing responses in vitro.

The virulent capacity of Pseudomonas aeruginosa can largely be ascribed to quorum sensing, i.e. the ability to evade host defence by a coordinated production and secretion of virulence factors. When P. aeruginosa is harboured in chronic wounds, a non-healing condition is often observed. In this study, we examined the in vitro cellular responses of the major cell types of re-epithelialization to supernatants of P. aeruginosa wild-type or an isogenic mutant not expressing quorum sensing-regulated virulence genes. We observed impairment of cell migration in keratinocytes (p = 0.009) and fibroblasts (p = 0.043) when supplementing medium with 20% P. aeruginosa culture supernatants. Cell proliferation was not significantly reduced, except for keratinocytes (p = 0.040). Data show compliance with in vivo observations of proliferating, non-motile epithelial cell behaviour in bacterially contaminated chronic wounds. Our findings suggest that quorum sensing may serve as an interesting target for controlling P. aeruginosa virulence in modern wound care.