Krüppel-like factor 4 inhibits the expression of interleukin-1 beta in lipopolysaccharide-induced RAW264.7 macrophages.

RAW264.7 macrophages and human peripheral blood mononuclear cells were treated with LPS to determine the expression of KLF4 and release of IL-1β. A full-length cDNA or short interference RNA of KLF4 was transfected into RAW264.7 macrophages; the expression and release of IL-1β were analyzed. The transcription and DNA binding activities of KLF4 to the IL-1β promoter were detected further. The results showed LPS treatment resulted in the increase of KLF4 level and IL-1β release; KLF4 overexpression decreased the expression of IL-1β, while KLF4 inhibition increased the expression of IL-1β; overexpression of KLF4 promoted the DNA binding activity of KLF4 to the IL-1β promoter and attenuated the transcription of IL-1β promoter, indicating an important role of KLF4 in regulating expression of IL-1β.