Fig. 1.

COX-2 mRNA and protein upregulation by LL-37 treatment. HGFs were treated with the indicated concentrations (0–50 µg/ml) of LL-37 for 12 h (a–c) or with 20 µg/ml of LL-37 for various times (0–24 h; d–f), and then total RNA and protein were extracted. Expression of mRNA for COX-1, COX-2, and GAPDH was analyzed by RT-PCR (a, d) and by real-time PCR (b, e) using a specific primer pair, and protein expression was assayed by immunoblotting (c, f) using antibodies specific to COX-1, COX-2, and GAPDH. The sizes of PCR products and proteins were as predicted, and the –RT sample was a negative control where the reverse transcriptase was omitted from the reverse transcription. The relative COX-2 mRNA induction (b, e) in LL-37-treated samples was expressed as mean ± SD from 4 separate experiments (** p < 0.01). The COX-2 mRNA expression in each sample was first normalized by GAPDH expression, and then the ratio of each experimental sample was compared to that of the control untreated sample, i.e., LL-37 at 0 µg/ml (b) or at 0 h (e), which was set to 1. a, c, d, f Representative images are from 4 independent experiments.