Epidermal growth factor receptor (EGF-R) of fibroblasts from 3 patients with scleroderma (progressive systemic sclerosis, PSS) was studied by radioiodinated-EGF binding assay. The binding was 60.9 +/- 4.0% of normal fibroblasts, and the Scatchard plots showed a decrease in the affinity for EGF, not in the number of EGF-R. PSS fibroblasts expressed higher levels (1.15-2.45-fold) of RNA for the v-erbB (EGF-R gene). All-transretinoic acid (retinoid) had little effect on EGF-R, v-erbB gene expression and the proliferation of PSS fibroblasts. These data concerning the abnormality in the EGF-R may all constitute a feature of PSS fibroblasts.