The serum IL-1 beta, IL-2, IL-4, IL-6, IL-8, TNF-alpha and soluble IL-2 receptor levels were measured, and the presence of anti-Fc gamma receptor (Fc gamma R) antibodies was investigated in the sera of 18 patients with systemic sclerosis (SSc). An increase of TNF-alpha was detected in 8 of the 18 cases. II-1 beta was elevated in all the 18 patients. Both IL-2 and IL-4 were elevated in 7 cases. The IL-6 level was elevated in 17 patients, while IL-8 was increased in all cases. The soluble IL-2 receptor level was elevated in 11 patients. Fc gamma R-specific antibodies were detected in the sera of 6 patients, and there was a significant association between anti-Fc gamma R antibody positivity and IL-4 elevation. The presence of anti-Fc gamma R antibodies may influence several cell functions and may contribute to the remarkable variability of cytokine levels in SSc.