Using light to stimulate fibroblast wound healing : identifying wavelengths for effective light-based therapies

Melling, Michael and Wright, Karen and Mort, Richard and Hardy, John (2020) Using light to stimulate fibroblast wound healing : identifying wavelengths for effective light-based therapies. Masters thesis, Lancaster University.

Text (2020MellingMRes)
2020MellingMRes.pdf - Published Version
Restricted to Repository staff only until 30 September 2025.
Download (1MB)

Abstract

Light therapy has been extensively explored as a means to promote wound healing. However, the exact parameters including the most optimal dose and most beneficial wavelengths are still disputed. Our objective was to test the effect of four commonly used wavelengths of light (780 nm infrared, 680 nm red, 565 nm green, and 430 nm blue) on the rate of wound closure of mouse fibroblast cells and determine which dose of light produced the greatest effect on the rate of wound closure. We explored the importance of proliferation and migration during wound closure following light treatment. NIH 3T3 mouse fibroblasts were grown on multiwell plates and subjected to scratch assays to simulate wounding. Wounds would then be subjected to a variety of doses of light of a specific wavelength or left untreated, and would be observed over the next 48 hours to record the rate of wound closure. To determine which parameters of wound closure were affected by light treatment, scratch assays done after a cell cycle block had been implemented and viability assays were performed. Our results indicated infrared (780 nm) and red light (680 nm) significantly increased the rate of wound closure. There was no dicernable increase in rate of wound closure with green light (565 nm). Blue light (430 nm) treatment was inhibitory to wound closure. The optimal doses for red and infrared light were 2 J/cm2. Red light affected only the proliferative rate, and infrared light affected only the rate of migration, with infrared light having the greater overall effect on the rate of wound closure. Due to the fact they worked through different pathways, a combined treatment was tested to see if the increase in rate of wound closure could be even greater and the data suggested that combined treatment with both 780 nm and 680 nm light was more effective than single wavelength treatment. This indicated that the 680 nm and 780 nm wavelenghths in combination might have the potential for therapuetic use.