Improvement of hypertrophic scarring by using topical anti-fibrogenic/anti-inflammatory factors in a rabbit ear model

ABSTRACT This study investigates the scar‐reducing efficacy of topical application of stratifin and acetylsalicylic acid (ASA) in a rabbit ear model. A total of five New Zealand white rabbits with four wounds per ear were examined. Either recombinant stratifin (0.002%) or ASA (0.5%) incorporated in carboxymethyl cellulose gel was topically applied on each wound at postwounding Day 5. Scars were harvested at postwounding Day 28 for histological analysis. The wounds treated with stratifin and ASA showed 82 and 73% reduction in scar volume, respectively, compared with that of untreated controls. A reduction of 57 and 41% in total tissue cellularity along with 79 and 91% reduction in infiltrated CD3+ T cells were observed in response to treatment with stratifin and ASA, respectively, compared with those of untreated controls. Wounds treated with stratifin showed a 2.8‐fold increase in matrix metalloproteinase‐1 expression, which resulted in a 48% decrease in collagen density compared with those of untreated controls. Qualitative wound assessment showed a reduced hypertrophic scarring in stratifin and ASA‐treated wounds when compared with the controls. This study showed that topical application of either stratifin or ASA‐impregnated carboxymethyl cellulose gel reduced hypertrophic scar formation following dermal injuries in a rabbit ear fibrotic model.