体内深部癌の光免疫療法のためのニードル型治療システムの開発とその応用

Lumin in a potent cell activating agent and a photsensitizer characterized by typical absorption peaks at 670nm and 770nm. In our preliminary results, a transplanted human cancer was dramatically cicatrized by collagen and removed by a photoimmunotherapy of small lumin administration with laser light irradiation. To treat a malignant tumor of the deep organs of the body using lumin with laser light, we developed new needle type photoimmunotherapeutic system. The system is composed of a needle to inject lumin solution and an optical fiber to guide the laser light to a cancer cell nest. To study the efficacy of the system, human lung cancer was grafted onto nude mice. After the tumor was hypertrophied, the mice were divided into four groups of three mice each; i. e. a control group, a group receiving laser irradiation only, a group receiving lumin administration only and a group receiving lumin administration with laser irradiation. Lumin of 5ng was injected and the tumor was irradiated with the laser (1.5mW, 60sec.). The treatment was performed every other day for three weeks. In the group receiving lumin administration with laser irradiation, the whole tumor was strongly cicatrized by collagen fiber from the stroma. The immunological function was investigated using the flow cytometric assay, which was analyzed by the two-color method based on immunofluorescence labeling with specific monoclonal antibodies for the sampling of 10⁴ cells harvested from mouse peripheral blood. The ratios of T and B cells in the control and laser groups were 0.25 and 0.23, respectively, and the ratio in the lumin administration group was 0.34. That in the lumin administration with laser irradiation group, on the other hand, was 0.57. Thus, it was suggested that the immune function was enhanced for the treatment of cancer by th needle type photoimmunotherapeutic system.