We examined IL-1α and IL-1β gene expression and protein production in human dermal fibroblasts from patients with systemic sclerosis (SSc) to investigate the abnormal function of SSc fibroblasts. Human dermal fibroblasts were biopsied from 13 patients with SSc. three patients with rheumatoid arthritis (RA) and five healthy normal controls (NC). Cells were cultured in serum-free media and total RNA was collected from second or third passage fibroblasts. In cultured SSc fibroblasts. IL-1α and IL-1β mRNAs were constitutively expressed and intracellular pro-IL-1α was present. These observations suggest that an autocrine effect of IL-1α contributes to the fibrosis in SSc.