Fig. 4.

Modulation of procaspase-3 cleavage in LL-37-treated neutrophils, which were exposed to a concentration range of 0.25–50 μg/ml LL-37, 30 ng/ml GM-CSF as a positive control, or endotoxin-free water as a vehicle control for 4 h in the presence of 10% FBS. Whole cell protein lysates were prepared and analyzed by SDS-PAGE and Western immunoblotting. (A) Immunoblots for expression of inactive procaspase-3 and active-cleaved caspase-3 are shown, representative of n = 5 different donors, and expression of the housekeeping protein GAPDH was assessed as a loading control. (B) Quantitative densitometry was performed, corrected for protein loading, expressed as a proportion of the vehicle alone-treated control sample, and displayed as mean values ± sem for n = 5 different donors. t-Test analyses were used to compare procaspase-3 and cleaved caspase-3 expression in LL-37- or GM-CSF-exposed samples with vehicle alone-treated controls. *, P ≤ 0.05; **, P ≤ 0.01.