Fig. 5.

a Treatment with LL-37 (4 µM) causes an acute and sustained rise in intracellular Ca²⁺ concentration assessed by laser-scanning confocal microscopy of Fluo-4-AM-loaded MG63 cells incubated in Ca²⁺ containing (2.5 mM) HEPES-buffered salt solution. No treatment (left panel) represents the Ca²⁺ signal in the presence of vehicle control (0.1% DMSO). Addition of 0.1% DMSO has no effect on Ca²⁺. The Ca²⁺ indicator Fluo-4-AM fluorescence is shown in red. b Line trace showing that both 0.4 and 4 µM LL-37 elevates Ca²⁺. c LL-37 (0.4 and 4 µM) has no effect on intracellular Ca²⁺ concentration in Ca²⁺-free solution. Ca²⁺-free conditions were achieved by removing CaCl₂ from the HEPES-buffered salt solution and by inclusion of 2 mM EGTA. Each experiment was repeated at least twice.