Abstract
OBJECTIVES/HYPOTHESIS: Tumor necrosis factor-alpha (TNF-alpha) is an inflammatory cytokine and apoptotic molecule that appears to be a mediator in inflammation and fibrosis. The objective of this investigation was to examine the effects of TNF-alpha on 3D Carbylan-GSX in vitro cultured human vocal fold fibroblasts (hVFFs), to provide insight into the mechanism responsible for the improved vocal fold wound healing that has been previous reported with Carbylan-GSX treatment. STUDY DESIGN: In vitro cell culture. METHODS: hVFF were cultured in 3D Carbylan-GSX and on polystyrene with different dosages of TNF-alpha (0, 0.1, 1, 10, and 100 ng/mL) with and without 10% fetal bovine serum (FBS). hVFF response to TNF-alpha was characterized by morphology, proliferation rates, and gene transcript levels for matrix metalloproteinase 1 (MMP1), matrix metalloproteinase 2 (MMP2), tissue inhibitor of metalloproteinase 3 (TIMP3), collagen I, collagen III, fibronectin, and TNF-alpha receptor. RESULTS: In 3D Carbylan-GSX, TNF-alpha inhibited hVFF proliferation in a dose-dependent manner. TNF-alpha (0.1-100 ng/mL) was shown to significantly downregulate TIMP3 and extracellular matrix-related mRNA transcript levels for collagen III and fibronectin and to upregulate MMP1 and MMP2 expression, resulting in increased MMP/TIMP3 ratios. TNF-alpha receptor expression was significantly upregulated in Carbylan-GSX compared to control polystyrene. Responses were more marked in 10% FBS culture. CONCLUSIONS: After vocal fold injury, locally injected Carbylan-GSX can enhance the role of TNF-alpha in remodeling the lamina propria layer of the vocal fold, accelerating wound healing. Carbylan-GSX has potential as a new therapeutic approach that may lead to better treatment of vocal fold wound healing.