Notes: FEN1-IN-4 is an inhibitor of flap endonuclease 1 (FEN1; IC50 = 30 nM for FEN1-336Δ).{69542} It also inhibits exonuclease 1 in a concentration-dependent manner. FEN1-IN-4 (10 µM) inhibits ATP-induced mitochondrial DNA (mtDNA) fragmentation and levels of cytosolic mtDNA in LPS-primed primary mouse bone marrow-derived macrophages (BMDMs).{69543} It also inhibits ATP-induced phosphorylation of STING in LPS-primed wild-type and Nlrp3-/- primary mouse BMDMs. FEN1-IN-4 (40 mg/kg) decreases peritoneal levels of IL-1β and neutrophil and monocyte infiltration in a mouse model of alum-induced peritonitis.