Vocal fold fibroblast response to growth factor treatment is age dependent: results from an in vitro study.

Introduction: Vocal fold (VF) fibroblasts (VFFs) are the central target in developing new strategies for treatment of VF injury and scarring. Nevertheless, only little is known about the basic biological characteristics of these cells. The aim of this study was to explore the impact of age of VFFs on the response to external growth factor stimulation.

Study Design: In vitro cell study using a rat model.

Methods: VFFs were extracted from young and aged rat VF 3 months after establishing unilateral injury. Resulting scar fibroblasts (SFs) and normal fibroblasts (NFs) were subsequently cultured separately with or without the addition of hepatocyte growth factor (HGF). After 24 and 72 hours, the production of hyaluronic acid (HA) was examined in the supernatant culture media using enzyme-linked immunosorbent assay.

Results: Only cultured SF and NF from young animals could be stimulated significantly in the production of HA by HGF. Within these, average percentage increase was higher in NF compared with SF.

Conclusion: The response of VFFs in cell culture to growth factors stimulation is highly depending on the age of the animals. This is another step in a nearer characterization of scar VFF and could furthermore be an important point when estimating the success of an intervention. Age-depending effects must be considered as an important factor in developing possible therapeutic agents for VF scarring.