Fig. 3. (a) Toxicity of GK-19 to mammalian cells. RPASMCs, HUVECs, HaCaT and 293 cells were cultured in medium containing different concentrations of GK-19 (0 -100 μM) for 48 hours. (n = 5). GK-19 causes a negligible toxicity to mammalian cells at effective antimicrobial concentrations. (b) Hemolytic activity of GK-19 on rat erythrocytes (c) Histology analysis of various organs of the mice treated with saline solution or GK-19 (25 μmol/kg), respectively. Heart, liver, spleen, lung and kidney were harvested at day 1, 3 and 7. No observable tissue damage, necrosis and inflammation were observed. Scale bar: 200 μm.