Functions of laser light, laser-absorbing dye and immunoadjuvants in Photo Dynamic Immuno Therapy

摘要

Photo Dynamic Immuno Therapy (PDIT) is a novel approach for treatment of metastic tumors. It involves an intratumor administration of a laser-absorbing dye and an immunoadjuvant, followed by a non-invasive laser irradiation. Previous studies using a novel immunoadjuvant, glycated chitosan, showed the effect of the treatment on a metastatic breast tumor in rats, including the eradication of treated primary tumors, regression of untreated metastases, and the evidence of immune responses induced by the treatment. To further understand the mechanism of PDIT, tumor-bearing rats were treated by different combinations of the three PDIT components. The rat survival rates and profiles of primary and metastatic tumors, after treatment by individual component and differnet combinations of the components, were analyzed. All the experimental groups without using immunoadjuvant showed none or little positive effect. The use of glycated chitosan, either by itself of in combination of other components, has showed noticeable impact on the survival rate of tumor-bearing rats. Furthermore, glycated chitosan with differnet concentrations was used. The experimental results showed that among the concentrations of 0.5