比较研究了可见波段405, 514, 633和785 nm低强度激光辐照HeLa细胞的促增殖效应。 实验采用100和1 000 J·m-2两种有效能量密度的可见光波辐照细胞， 照射后24, 48, 72 h采用MTT法检测细胞活性。 结果表明， 405, 633, 785 nm激光均能促进HeLa细胞增殖， 且呈波长和时间依赖性； 633 nm激光辐照对细胞促增殖效应最显著； 514 nm激光辐照对HeLa细胞促增殖效应较不明显。 不同光剂量对细胞增殖效应不同， 405, 633, 785 nm激光辐照时能量密度为1 000 J·m-2的辐照组细胞增殖均较100 J·m-2辐照组明显， 而514 nm激光辐照时1 000 J·m-2辐照组与100 J·m-2辐照组细胞增殖的差异不明显。

The aim of this in vitro study was to evaluate the effects of low level laser irradiation on the proliferation of HeLa cells using 405 nm diode laser, 514 nm argon laser, 633 nm He-Ne laser, or 785 nm diode laser. The cells were seeded on 96-well microplates for 24 h in 5% fetal bovine serum containing medium, then irradiated with the laser at dose of 100 and 1 000 J·m-2, respectively. At the time point of 24, 48, 72 h after irradiation, cell viability was assessed by MTT assay. The results show that 405, 633 and 785 nm laser irradiation induces wavelength-dependent and time-dependent proliferation. 633 nm laser irradiation results in a stimulatory proliferation effect that is most significant, whereas 514 nm laser irradiation produces little increase in cell proliferation. Low level laser irradiation increases cell proliferation in a dose-dependent manner. 1 000 J·m-2 laser irradiation is more effective in increasing cell proliferation than 100 J·m-2 laser irradiation using 405 nm diode laser, 633 nm He-Ne laser, or 785 nm diode laser, but not as effective as using 514 nm argon laser.