Abstract
Purpose :
Posterior capsular opacification (PCO) is a disease partly resulting from the collective migration of residual lens epithelial cells (LECs). We have previously found potential effects of narrowband monochromatic lights on risk of PCO that a wavelength within 400 – 480 nm and 570 – 800 nm respectively reduce and enhance LEC migration. This study examined how the combined effects arise in broadband light using in vitro wound healing assay.
Methods :
A human LEC line SRA01/04 cells were cultured as a monolayer and created a wound with a width of 500 µm. We irradiated broadband lights with different cut on properties, 422 – 800 nm, 450 – 800 nm, and 490 – 800 nm with 1000 – 2500 lx, which has been reported to have almost no effect on survival rate, and analyzed the effects on LEC migration in wound healing assay. The desired spectrum was attained with a xenon lamp filtered by a VIS mirror module and a long pass optical filter. The light was provided by the light guide from the upper side of the culture dish in an incubator. The images were acquired by an incubation monitoring device every 10 min for 30 h.
Results :
In the dark, LECs migrated at temporally constant speed to close the 500 µm wide wound in 30 h. Migration speed was also temporally constant at 2500 lx for each 422 – 800 nm, 450 – 800 nm, and 490 – 800 nm light irradiation. The speed in the 422 – 800 nm light was lower than in the dark, and comparable for 450 – 800 nm and 490 – 800 nm. At 1250 lx, migration speed was not temporally constant. Under the 422 – 800 nm light irradiation, migration speed was almost the same as in the dark in the first 20 h and lower in the following 10 h. In contrast, the speed was higher than in the dark in the first 15 h, and then slowed down for 450 – 800 nm and 490 – 800 nm lights.
Conclusions :
Our results newly demonstrated that the effect of 422 – 480 nm component to suppress LEC migration, i.e., decrease the risk of PCO, is more dominant than the enhancing effect of 570 – 800 nm component in the 422 – 800 nm broadband light. A balanced inclusion of the 420-450 nm band of blue light may be effective in controlling light spectrum to decrease a risk of PCO. Further careful studies considering previously mentioned disadvantages of blue light, such as induction of reactive oxygen species, are required to optimize a design of the optical filter for advanced PCO prevention.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.