FIGURE 6.

LL-37 affects multiple signal pathways and has synergy with poly(I:C) in stimulating the NF-κB pathway. A, keratinocytes were pretreated with LL-37 followed by stimulation with poly(I:C) for 2 h before cells were harvested for immunoblotting analyses using antibodies against phosphorylated and total forms of the following proteins: p38, AKT, IKK, NF-κB, and ERK. B–E, keratinocytes were preincubated with either p38, IKK, EGFR, or an endosomal inhibitor for 30 min prior to stimulation with 4 μm LL-37 (LL) and 0.1 μg/ml poly(I:C) (P(I:C)) for 16 h before RNA was isolated and FGF2 mRNA was quantified via qPCR. F–I, siRNA knockdown was performed on keratinocytes 72 h before stimulation with 4 μm LL-37 and 0.1 μg/ml poly(I:C) for 16 h before cells were collected, RNA was isolated, and qPCR measurements were performed. p values were calculated by two-way analysis of variance. Data are mean ± S.D. of biological replicates, n = 3, and are representative data from at least two or more independent experiments. Error bars represent S.D.