IL1B and systemic sclerosis: As regards the apparently unexpected IL-1β findings, it should be noted that previous studies demonstrated that IL-1α, rather than IL-1β, peculiarly plays an important role in promoting the activation of SSc dermal fibroblasts (Kawaguchi, 1994; Higgins et al., 1999; Hutyrová et al., 2004; Kawaguchi et al., 2004).