ABSTRACT
Objective To investigate the photodynamic effect induced by laser and use it as a method for purging of minimal residual tumor cells from autologous peripheral blood stem cell grafts. Methods We studied the effect of various concentrations of hematoporphyrin derivative (HPD) combined with of different time of laser irradiation on human leukemia cell line K562, breast tumor cell line MCF-7 and human umbilical cord blood-derived hematopoietic stem/progenitor cells by using MTT assay to compare the photodynamic effect between cell lines of each group. Results HPD or laser irradiation alone had no apparent cytotoxicity while the application of HPD plus laser exposure caused photosensitization. HPD plus laser irradiation was more efficient for killing K562 cells and MCF-7 cells than doing the normal human umbilical cord blood-derived hematopoietic stem/progenitor cells. The photodynamic effect on K562 cells and MCF-7 cells was positively correlated with the increase of treatment duration and HPD concentration. Conclusion These results indicated that the laser photodynamic effect mediated by HPD might be used for purging autologous peripheral blood stem cell grafts in vitro.
ABSTRACT
Department of Pathological Anatomy of Second Military Medical College Photosensitive reaction of HPD and its cytotoxic action were studied, focussing on the spectral effect of the irradiating light. A human hepatocarcinoma cell line(SMMC-7721)with HPD was used. Killing effects on tumor cells after irradiation of light in three different wave-bands were observed, both qualitatively and quantitatively.Results were compared with those of Kinsey and Matsushima.