IL1B and rheumatoid arthritis: For example, epigallocatechin gallate (EGCG at 50 mg/kg/day/10 days) diminished synovial fibroblasts, the activity of the transforming growth factor β-activated kinase 1 (TAK1), a key protein in the signaling of IL-1β and TNF-α, in animals with experimental RA induced with CFA [35].