Figure 1.

PGE₂ production and COX-2 expression are decreased in stimulated psoriatic fibroblasts. Cells were treated with 2.5 ng/ml IL-1β or 1 μg/ml TPA for 24 h. (A) 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for cell viability (n = 4 biopsies) and (B) Prostaglandin E₂ (PGE₂) determined by radioimmunoassay (n = 6 biopsies) were performed in duplicate. (C,D) COX-2 protein expression assessed by Western blotting (n = 3 biopsies). Data represent mean ± SD. *p < 0.05, ***p < 0.001 vs. unstimulated fibroblasts (B) and +p < 0.05, +++p < 0.001 vs. healthy fibroblasts (HF) using Sidak's multiple comparison test. PF, psoriatic fibroblasts. (E) COX-2 protein expression determined by immunocytochemistry (representative photomicrographs of three independent experiments).