Figure 3.

Dose-dependent effects of ECC55 and leontopodic acid on the chemokine and growth factor released from cultured human keratinocytes treated with proinflammatory combination of TNFα and IFNγ (T/I). Concentrations (ng/10⁶ cells) of granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin 8 (IL-8), interferon gamma-produced protein of 10 kDa (IP-10), and monocyte chemotactic protein-1 (MCP-1) were determined in the cellular supernatant at 24 h after keratinocyte challenge with T/I known to stimulate maximal inflammatory response. Keratinocytes were pretreated for 30 min with increasing concentrations (μg/mL) of either ECC55 or pure commercial leontopodic acid. The corticosteroid triamcinolone was used as a positive control for effective inhibition of cytokine/chemokine release at the two concentrations indicated. Error bars in all figures correspond to S.D. Background release of IL-8 was 0.29 ± 0.04 ng/10⁶ cells, IP-10 was 0.001 ± 0.000 ng/10⁶ cells, GM-CSF was 0.07 ± 0.01 ng/10⁶ cells, and MCP-1 was 0.018 ± 0.02 ng/10⁶ cells. Spontaneous production of IP-10 and MCP-1 was not changed in the presence of either ECC55 or pure commercial LA, whereas basal GM-CSF and IL-8 levels were decreased by ECC55 and LA dose dependently.