Abstract: Objective To investigate the role of histone acetylation in regulating influenza virus replicative intermediate
double-stranded RNA (dsRNA)-induced interleukin-6 (IL-6) expression in A549 cells. Methods A549 cells were treated with
influenza virus replicative intermediate dsRNA, histone deacetylase (HDAC) inhibitor trichostatin A (TSA), or HADC small
interfering RNA (siRNA). The changes in the cellular IL-6 promoter activities were detected by dual-luciferase assay, and IL-6
mRNA and protein expressions in the cells were determined using real-time RT-PCR and ELISA, respectively. Results
Influenza virus replicative intermediate dsRNA obviously up-regulated IL-6 expression in the cells. HDAC inhibitor TSA
significantly enhanced the activity of IL-6 promoter and increased IL-6 mRNA expression in A549 cells, and HDAC3 may play
an important role in this process. HDAC inhibitor TSA and DNMT inhibitor DAC showed no synergic effect in regulating IL-6
expression. Conclusion Influenza virus replicative intermediate dsRNA-induced IL-6 expression in A549 cells is regulated by
histone acetylation.