Figure 2.

Caspase-1-independent release of IL-18 in UV-B-irradiated primary HCE cells. Primary HCE cells were treated with TNF-α (10 ng/mL) for 24 hours followed by irradiation under UV-B light (0.2 J/cm²). The secretion of IL-18 was measured for 24 hours after the UV-B exposure from the cell culture medium samples (A). Alternatively, cells were pretreated with the caspase-1 inhibitor (100 µM) at 1 hour before UV-B irradiation (B). ELISA results of extracellular IL-18 have been combined from (A) three or (B) two donors with two parallel samples per donor. Data are represented as mean ± SEM. **P < 0.01, ***P < 0.001, ns = not significant, Mann-Whitney U-test; casp.1 inh. = caspase-1 inhibitor.