| Sumario: | Aim: Wounds of elderly patients or those with poor nutritional status, comorbidities, etc., are more susceptible to bacterial infection delaying healing. S.aureus and P.aeruginosa are the most prevalent species occurring in patients with infected wounds. Consequently, prevention and treatment of wound infections play an important role in wound management. Here, a new 3D-skinwound- model with S.aureus or P.aeruginosa infection was used to investigate the antimicrobial efficacy of antimicrobial dressings. Method: 3D-full-skin-models were prepared and wounded by 3-mm-biopsy-punch. Subsequently, they were infected with S.aureus or P.aeruginosa. Afterwards, wounds were treated with antimicrobial dressings. Microbial burden was determined by cfu-count and fluorescence imaging. Cytokine secretion was quantified by specific ELISA. Moreover, histological specimen were prepared and examined after staining with haematoxylin and eosin. Results / Discussion: Without treatment, infected skin wound models showed extensive tissue damage and bacterial invasion. While S.aureus was mainly confined to the wound margins, P.aeruginosa spread throughout the model. Infection caused time dependent cytokine increase and inflammatory marker release. Antimicrobial treatment led to a significant reduction of S.aureus and to a lesser extent of P.aeruginosa improving the wound situation. Conclusion: A wound infection model for evaluation of antimicrobial dressings was developed. The model is easy to standardize, featuring a uniform wound size and wound depth. Bacterial infection led to secretion of inflammatory markers and was visible as tissue destruction in the histological specimen. Using this model, differences of antimicrobial dressings against S.aureus and P.aeruginosa infections in a wound situation were demonstrated. Hence, this model provides a valuable, application-oriented tool for testing of antimicrobial dressings.
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