Objective: To test the effect of high-mobility group box protein 1 (HMGB1) alone or in synergy with interleukin-1β (IL-1β) on the expression of IL-8 in human airway epithelial cells in vitro.
Methods: Human airway epithelial 16HBE and A549 cell lines were incubated with HMGB1 (100 ng/ml) in the absence or presence of IL-1β (10 ng/ml) for 24 h, and the changes of IL-8 mRNA and protein expressions were assessed using quantitative PCR and enzyme-linked immunosorbent assay (ELISA).
Results: In the two human airway epithelial cell lines, HMGB1 alone did not produce obvious effect on the expression of IL-8, but in the presence of IL-1β, HMGB1 caused a significant increase of IL-8 expressions at both the mRNA and protein levels.
Conclusion: HMGB1 in synergy with IL-1β increases the expression of IL-8 in human airway epithelial cells, which provides new evidence that HMGB1 contributes to neutrophilic airway inflammation by regulating IL-8 expression.