FIGURE 6.

Membrane activity. A, hemolytic effects. Data for the peptide FFF21 are presented, and corresponding data for LL-37 included for comparison. The cells were incubated with the peptide at the indicated concentrations. The absorbance of hemoglobin release was measured at 540 nm and is expressed as % of Triton X-100 induced hemolysis (note scale of y axis). 2% Triton X-100 served as a positive control. B, Effects of peptides on HaCaT cells. Cell permeabilizing effects of the indicated peptides (upper panel) were measured by the LDH-based TOX-7 kit. LDH release from the cells was measured at 490 nm and was plotted as % of total LDH release. The MTT assay (right panel) was used to measure viability of HaCaT keratinocytes. In the assay, MTT is modified into a dye, blue formazan, by enzymes associated with metabolic activity. The absorbance (abs.) of the dye was measured at 550 nm.