FIG. 4.

Hemolytic and growth inhibition activities of K₄K₂₀-S4 (A) and K₄-S4(1–13)a (B). Infected cells at the trophozoite stage were isolated by Percoll gradient and resuspended in culture medium containing increasing amounts of dermaseptins for 2 h of incubation. To assess lytic activity, cells were pelleted, and the absorbance of hemoglobin in the supernatant was determined by absorption spectroscopy (405 nm). Full lysis was obtained by lysing the same number of cells in an equal volume of distilled water. To assess parasite growth, [³H]hypoxanthine was added after 2 h of exposure to peptides. Parasite-associated radioactivity was measured after 4 h of incubation. Stars, inhibition of trophozoites growth; rectangles, lysis of trophozoite-infected RBC; circles, lysis of normal RBC.