Fig. 8.

Effect of ferritin light chain (FTL) knockdown on methemoglobin-mediated IL-8 and MCP-1 expression and release. A: A549 cells were treated with 10 nM control (Ctl) or FTL siRNA for 40 h. Cells were harvested and levels of FTL were measured by ELISA relative to total protein. Comparison between conditions was made by Student's t-test, **P < 0.01. B–E: A549 cells were treated with siRNA as above, followed by 10 μM methemoglobin (shaded bars) or medium (open bars). After 24 h IL-8 and MCP-1 levels (B and C) were measured in the cell supernatant by ELISA. Total RNA was harvested after treatment with methemoglobin for 2 h. Levels of IL-8 and MCP-1 mRNA relative to the housekeeping gene were quantified by real-time PCR (D and E).