Individual and synergistic regulation of β-defensin 2 (DEFB4) by NTHi lysate and IL-1α. Luciferase assay of β-defensin 2 (DEFB4) promoter activity shows dose-dependent effect of NTHi lysate (A) and IL-1α(B) in HMEEC cells. Real time quantitative PCR (C) shows that HMEEC cells respond to NTHi treatment and up-regulate β-defensin 2 while Hela and A549 cells respond poorly. Insect: standard deviations (SD). Co-treatment of the cells with suboptimal doses IL-1α and NTHi lysate demonstrates a synergistic effect on the activation of the β-defensin 2 mRNA in HMEEC cells. The synergistic effect was not noted in Hela or A549 cells (D). Luciferase assay of HMEEC cells (E) shows synergistic transcriptional regulation by NTHi lysate (1:100 dilution) and IL-1α (50 pg/ml) co-treatment. Values are given as the mean ± standard deviation. N = 3. *: p < 0.05, **: p < 0.01.
Moon et al. BMC Infectious Diseases 2006 6:12 doi:10.1186/1471-2334-6-12