低功率激光照射（LPLI）凭借其广泛的促细胞增殖效应而被应用于临床医学。最近有研究表明高通量低功率激光照射（HF-LPLI）能够通过触发活性氧（ROS）产生抑制细胞生长甚至诱导细胞凋亡。然而HF-LPLI诱发细胞内的光化学过程以及产生相关生物效应的机制仍不清楚。本项目旨在前期LPLI诱导细胞增殖及HF-LPLI诱导细胞凋亡相关研究工作基础上，针对光与细胞初始相互作用机制，采用传统细胞生物学与新型光学检测手段相结合的研究方法，开展系统的基础研究。拟明确LPLI引起不同生物效应的作用阈值，探明HF-LPLI诱导细胞ROS产生的位点及亚型，阐明HF-LPLI与细胞内源光受体的原初反应机制及与线粒体ROS产生的关系。本项目研究目标的实现将明确HF-LPLI的作用机制，拓展LPLI的应用领域，有望提供一种具有潜力的线粒体选择性损伤的激光治疗手段，并为LPLI的临床应用提供剂量参考。

Low-power laser irradiation (LPLI) has been applied clinically via its widely effect on promoting cell proliferation. Recent study showed that high fluence LPLI (HF-LPLI) inhibited cell growth or even induced cell apoptosis through triggering reactive oxygen species (ROS) generation. However, the mechanism involved in the intracellular photochemical reaction and its related biological effects has not been elucidated yet. Using the combination of traditional cell biology and novel optical detection means, the current systematic research will be performed focusing on the initial interaction mechanism between light and cells, based on our previous study on LPLI's promoting cell proliferation and HF-LPLI's inducing cell apoptosis. The goals of the project are to clarify the threshold of LPLI for triggering different biological effects, the generation site and kinds of ROS by HF-LPLI, and the initial interaction mechanism between HF-LPLI and its endogenous photoacceptor, and the correlation of the initial photochemical reaction with the mitochondrial ROS production. The achievement of the goals will clarify the tumor cell killing mechanisms of HF-LPLI, expand the application of LPLI, provide a potential laser tumor therapy modality characterized by mitochondrial selective damage, and also giving the reference doses for clinical application of LPLI.