Cytokine and growth factor mRNA expression patterns associated with the hypercontracted, hyperpigmented healing phenotype of red duroc pigs: A model of abnormal human scar development?

Background: Skin wounds in red Duroc pigs heal with the formation of hypercontractile, hyperpigmented scars, similar in some respects to human hypertrophic scars. Objective The goal of this study was to characterize the mRNA expression patterns for a subset of relevant cytokines, growth factors, receptors, and transcriptiou factors involved in the red Duroc scarring phenotype. Methods: Full-thickness and deep dermal wounds were created on the backs of juvenile female red Duroc pigs. Samples were taken every two weeks postwounding and total RNA and DNA were extracted and quantified. RT-PCR was performed using porcine gene-specific primers for 15 relevant molecules. Results: The majority of molecules examined exhibited a biphasic pattern of expression, with peaks of expression at days 14 and 56 postinjury. Conclusions. The molecular expression pattern observed correlates well with the gross healing phenotype and matrix molecule expression patterns previously reported in red Duroc pigs. These findings enhance our understanding of the processes associated with fibroproliferative scar-formation.