The expression of CCL-23 mRNA was found in monocytes stimulated with IL-1β (Forssmann et al., 1997) and IL-4 (Nardelli et al., 1999; Novak et al., 2007) and can also be detected in SFs from patients with rheumatoid arthritis (Berahovich et al., 2005). Here, IL4 is linked to rheumatoid arthritis.