THE ROLE OF INFLAMMATORY CYTOKINES IN WOUND HEALING

Abstract

TNF (by murine ELISA) and collagenolytic activity (CA by in vivo labelled collagen fibril degradation assay) were measured in wound fluid from silicone reservoirs on post-wounding days 1, 3, and 5 (n = 5 per group). Hydroxyproline (HOP, nmol/mg sponge) incorporation (by HPLC) in polyvinylacohol sponges and breaking strength (BS, as determined by tensiometry) in linear wounds were assessed on days 5, 7, 10, and 14 (n = 5 per group). The data demonstrate significantly increased BS at 5 and 7 days in endotoxin-resistant J mice compared with that in endotoxin-sensitive N mice. An early, significant reduction in TNF production in J mice corresponded with a significant increase in CA on day 1, increased collagen production at day 7, and increased procollagen gene transcription at early time points. Conclusion. The reduced production of inflammatory cytokines including TNF in the wound fluid of J mice corresponded with an early improvement in wound tensile strength. An accelerated accumulation of collagen in the wounds of J mice, perhaps resulting from a significant decrease in collagenolytic activity or increased collagen production, are potential mechanisms. The data suggest that cytokines produced in normal healing of clean wounds may contribute to a delay in increased tensile strength.