Effect of laser irradiation on functional activity of human neutrophils: activation of myeloperoxidase in the presence of hematoporphyrin.
Laser irradiation (lambda=540 nm) of the blood increased myeloperoxidase activity in polymorphonuclear leukocytes. We revealed photoinduced activation of myeloperoxidase in irradiated neutrophils in the presence of hematoporphyrin. The photodynamic effect was most pronounced, when the modifier was incorporated into the cell membrane or sorbed on it.