[Cytotoxic effect of hematoporphyrin derivative (HPD) plus light irradiation in vitro]

Cytotoxic effect of HPD plus light irradiation on PTK2 and HeLa cells in vitro were studied by laser microbeam irradiation. The dynamic changes, in three different steps as observed in the cells ranged from visible damage to cell lysis, were recorded at the monocellular level. It was found that the speed of the cytotoxic process varied chiefly with the dose of light used. The cytotoxic progress of PTK2 and HeLa cells was compared and analyzed. In addition, the cytotoxic effects of three different laser wavelengths (6328A, 5145A and 4880A) plus HPD were compared. The most significant killing effect occurred at 6328A wavelength of red light.