Effects of monochromatic low-intensity light and laser irradiation on adhesion of HeLa cells in vitro

Background and Objective: The adhesion of HeLa cells was evaluated after irradiation with monochromatic low-intensity light or laser irradiation. It is well known that the cell-cell and cell-matrix adhesion changes during wound repair. For better understanding of low-power laser light action on the wound healing process, it would be of interest to study the light action on cellular adhesion in vitro. Study Design/Materials and Methods: The monochomatic light was in the range 580-860 nm (bandwidth 10 nm, 5-150 J/m², 1.3 W/m²) and the He-Ne laser irradiation was 632.8 nm (100 J/m², 10 W/m²). Cell-cell and cell-glass adhesion were evaluated after irradiation of HeLa cells. Results: It was found that cell-cell and cell-glass adhesion increased following irradiation depending on the irradiation conditions (wavelength, dose) and the time elapsed after the irradiation. The cell attachment to glass surface increased after irradiation of samples of HeLa cells in suspension. Conclusion: The adhesion was stimulated in the wavelength ranges 600-625, 645-700, and 720-850 nm with maxima at 620, 680, 750, and 820-830 nm, respectively.