Background/aims: Human pulmonary alveolar epithelial (A549) cells release interleukin-8 (IL-8) on stimulation by lipopolysaccharide (LPS) and alpha-toxin. We hypothesised that the perfluorocarbons (PFCs), perflubron and FC-84, would block stimulation of A549 cells by these toxins.
Methods: The levels of IL-8 production in A549 cells were measured following exposure to toxins for 24 h with or without PFC. The amount of IL-8 released from A549 cells was measured by enzyme-linked immunosorbent assay, and the level of IL-8 mRNA was measured by real-time RT-PCR.
Results: When stimulated with LPS or alpha-toxin, IL-8 release from A549 cells increased. There were no significant differences in level of IL-8 release between cells pre-incubated for 24 h with or without PFC after toxin stimulation for 24 h. When PFC was administered along with LPS stimulation, the level of IL-8 release was decreased (LPS control, 1,398 +/- 110 pg/well; FC-84, 686 +/- 50 pg/well; perflubron, 749 +/- 137 pg/well; p < 0.05). Levels of IL-8 mRNA expression were significantly higher with than without LPS, and those with LPS and perflubron were significantly lower than those with LPS alone.
Conclusions: The results show that PFCs block stimulation of A549 cells by LPS or alpha-toxin. PFC may be useful clinically in treatment of pulmonary inflammation in the alveolar space.