Plasma-generated nitric oxide radical (NO•) promotes the proliferation of fibroblast cells in liquid

The promotion of cell proliferation by non-equilibrium atmospheric-pressure plasma is a promising technology for regenerative medicine. The fibroblast suspension was irradiated with electrically neutral radicals. Radial irradiation was performed using an atmospheric-pressure radical generator with a working gas mixture of Ar, O-2,O- and N-2. Carboxy-PTIO (c-PTIO), a scavenger of nitric oxide radical (NO & BULL;), was dissolved in the fibroblast suspension. Selective irradiation with electrically neutral radicals promoted fibroblast proliferation by 36% without c-PTIO in liquid. In contrast, proliferation-promoting effects were significantly reduced to 13% with c-PTIO. Fluorescence probes for reactive oxygen and nitrogen species (RONS) and NO & BULL; showed that intracellular RONS and NO & BULL; levels were increased by radical irradiation and reduced with c-PTIO in the fibroblast suspension. NO & BULL; was detected in the radical-irradiated solutions using ERS. These results suggested that plasma-generated NO & BULL; promotes fibroblast proliferation in liquids.