Modelling biofilms on infected chronic wounds

Abstract

Chronic wounds, for instance venous, pressure, arterial and diabetic ulcers, are a major health problem throughout the world. Compared with normal wounds, those that take more than four weeks to heal are defined as chronic. Interestingly, the numbers of patients suffering from chronic wounds and the cost for treatment have been increasing during the past two decades. There is increasing evidence that suggests that bacteria infect those chronic wounds and there exist as a biofilm, which affects the wound healing and success of wound treatment. To study biofilms in infected wounds, both in vitro and in vivo biofilm models have been developed. In this project, the colony biofilm assay was used to determine antibiotics effect on removing biofilm. The results of this study so far indicated that mature Staphylococcus aureus biofilms were resistant to vancomycin treatment, which works effectively on killing planktonic cells. However, other antibiotics used topically for healing infected chronic wounds, for example, gentamicin, tetracycline, fusidic acid and mupirocin, were more effective at killing mature biofilms in the colony biofilm model. These sets of experiments were also done with pig skin based on colony biofilm assay. This project aims to build up a new ex vivo dynamic model using pig skin and a 3D print flow chamber to mimic chronic wounds. Hence, the results gathered from the colony biofilm assay will be compared with those obtained for the newly developed model. This model can then be used to study the drug delivery and topical treatment of chronic wounds.