CXCL1 and rheumatoid arthritis: Ahmed et al. have shown that epigallocatechin-3-gallate (EGCG) (10–50 μM), an active constituent in green tea, significantly inhibits the IL-1β-induced production of CXCL5, CCL5 and CXCL1 incubated with rheumatoid arthritis synovial fibroblasts in serum-free medium for 12 h [43].