Effect of a synthetic extracellular matrix on vocal fold lamina propria gene expression in early wound healing

An improved understanding of molecular response in the vocal folds to a synthetic extracellular matrix (sECM) during early wound repair is essential for understanding functional improvement of the tissue and implementation of future tissue-engineering strategies. The present study used real-time reverse transcriptase polymerase chain reaction to measure transcript expression of selected markers (procollagen alpha 2 type I, fibronectin, fibromodulin, hyaluronan synthase 2, and hyaluronidase 2) in 20 rabbits that underwent vocal fold biopsy bilaterally. After the biopsy, Carbylan-GSX 5% was injected immediately into the left vocal fold, and saline was injected into the right vocal fold. Two unwounded normal rabbit larynges were also harvested. Animals were sacrificed at days 1, 3, 5, and 10 post-surgery. At days 1, 3, and 10, no significant differences were found between the Carbylan-GSX-treated and saline-treated groups. At day 5, significant differences in procollagen (p = 0.02), fibronectin (p = 0.02), and transforming growth factor beta1 (p = 0.02) between the Carbylan-GSX-treated and saline-treated groups were measured. The presence of a sECM in the wound bed during the early stages of repair amplified the normal rabbit vocal fold wound-healing response over a short period of time. This amplification provided an optimal environment for tissue regeneration and may lead to the recovery of the functional biomechanical properties of the vocal folds necessary for voice production.