Abstract
Fine structure of neurofibromas developed on the skin of von Recklinghausen’s disease was studied with a special reference to the stroma, using tannic acid and ruthenium red staining. We have demonstrated that the tumor is formed by a complex of “structural constituents”. The element is composed by a central Schwann’s cell-like cell body, coaxially and alternatingly arranged processes of the Schwann-like cell and the fibroblasts, and the connective tissue material between these processes. We found elastica in the stroma, which has never been reported. With increase of the stromal amount, the fibroblast processes became thinner as to embrace the connective tissue but the other processes did not change. The basal lamina (BL) around the Schwann’s cell-like cell processes, which held an axon, frequently extended and mingled with the collagen fibers and the anionic sites on the BL were irregularly distributed. Treatment with chondroitinase ABC resulted no changes on the sites of the BL, but heparinase digested partially the BL itself and reduced the size of the anionic sites on the remaining BL. Coupled with the recent reports that proteoglycans on the BL influence the neighbouring cell proliferation and the stroma formation, our results indicate that the neurofibromas in von Recklinghausen’s disease are originally attributable to the neural component and the proliferated Schwann-like cells and fibroblasts with their product of the connective tissue stroma would be the target and/or morphological results through the neural abnormal induction.
