PLASMA TGF-BETA IN SYSTEMIC-SCLEROSIS - A CROSS-SECTIONAL STUDY

Objectives-To determine whether the active 25 kDa form of the fibrogen ic cytokine transforming growth factor beta (TGF beta) can be detected in plasma from patients with systemic sclerosis and to examine the re lationship between plasma TGF beta and clinical markers of disease sev erity and serum concentrations of the aminoterminal peptide of type II I procollagen (PIIINP) (a laboratory marker of the fibrotic process). Methods-A cross sectional study was made of 39 patients with systemic sclerosis (11 diffuse and 28 limited), nine patients with primary Rayn aud's disease and 60 healthy controls. TGF beta 1 and TGF beta 2 were measured by enzyme linked immunosorbent assay (ELISA) (sensitivity 100 pg/ml) and PIIINP by radioimmunoassay. Results-TGF beta 1 was detecte d in plasma from six of 39 patients with systemic sclerosis but not in any patient with primary Raynaud's disease or healthy controls. TGF b eta 2 was not detected in plasma from patients or controls. No clear r elationship was demonstrated between TGF beta 1, clinical features or PIIINP concentrations. Conclusions-The 25 kDa form of TGF beta 1 can b e detected in the plasma of some patients with systemic sclerosis. Thi s provides limited support for hypothesis that this cytokine plays a r ole in the pathogenesis of this disease. However, longitudinal studies , particularly in early diffuse disease, are required to clarify the r elationship between circulating TGF beta 1 and disease activity.