FIP22 is a potent and selective IRAK4 PROTAC degrader (HEK293T cells: DC50 = 3.2 nM, THP-1 cells: DC50 = 10.6 nM). FIP22 induces the ubiquitin-proteasome system by forming an IRAK4-FIP22-CRBN ternary complex (EC50 = 12.63 nM), thereby potently blocking IRAK4-mediated NF-kappaB and MAPK signaling pathways. FIP22 can be used for the study of atopic dermatitis (Pink: IRAK4 ligand (HY-175765), Blue: CRBN ligand (HY-W087383), Black: Linker (HY-46871))[1].
