Caspase-11 gene expression in response to lipopolysaccharide and interferon-γ requires nuclear factor-κB and signal transducer and activator of transcription (STAT) 1

Murine caspase-11, together with caspase-1, is essential for the production of IL-1beta in response to lipopolysaccharide (LPS). In most cells, caspase-11 is only expressed upon induction with pro-inflammatory stimuli. To understand how caspase-11 expression is transcriptionally regulated, we isolated the caspase-11 gene promoter by genome walking and investigated the mechanisms regulating caspase-11 gene expression in macrophages that are treated with LPS and interferon-gamma. Transient transfections with caspase-11 promoter-luciferase reporter constructs and deletion/mutation analysis revealed an essential role for NF-KB binding in the up-regulation of caspase-11 in response to LPS. In the case of interferon-gamma stimulation, signal transducer and activator of transcription 1 binding to the caspase-11 promoter could be shown to be required for caspase-11 expression.