Definitive treatment of burns often requires surgical excision and grafting. However, the facilities and personnel needed for this may not be acutely available in the combat casualty care arena. This creates the need for interim care strategies that would promote healing and prevent infection until more definitive treatment can be provided. Topical apyrase, an adenosine triphosphate ATP hydrolyzing enzyme, has local anti-inflammatory and anti-microbial characteristics that proved beneficial and eliminate infection without local toxicity. In the first aim of the study, we developed a porcine model of partial thickness burn injury to compare the effectiveness of two dosages of apyrase with a standard method of treatment and the in vivo work was finished in this annual reporting period. Serial biopsies, wound measurements and photographs were taken over time to assess inflammation and healing responses. Final results are pending. Work on Specific Aim II involving infected burn wounds began in this reporting period as well. Optimal bacterial growth conditions were defined and inoculum size determined for the infection experiments. Wounds were infected and treatments applied one day after burn and then daily for 4 days. Most notably, blinded, assessments of wound characteristics suggest that infected wounds treated with apyrase more closely resemble uninfected wounds at Day 3 post burn than do infected burns treated with either saline of sulfamylon. The results of culture and biofilm studies will provide more quantitative assessments and will be available at the conclusion of the in vivo studies.