EXPRESSION OF TYPE-VII COLLAGEN, THE MAJOR ANCHORING FIBRIL COMPONENT, IN NORMAL AND NEOPLASTIC HUMAN NERVOUS-SYSTEM

The distribution of type VII collagen was examined in the normal human nervous system, in brain tumour biopsies and in glioma cell lines by immunohistochemistry and western blotting. In normal tissue, positivit y was observed beneath choroid plexus epithelial cells and around pine al gland and pituitary gland cell nests, while other brain regions and peripheral nerves were negative. Expression was preserved in most rel ated tumours (choroid plexus papilloma, pineoblastoma, pituitary adeno ma). Scattered abnormal vessels showed neo-expression of type VII coll agen in about half of the astrocytic and ependymal tumours, Glioma cel ls in situ were consistently negative for type VII collagen, whereas t he glioblastoma cell lines were positive. Our results suggest that anc horing fibrils or at least epitopes of their major structural componen t are present in normal and pathological cerebral structures, indicati ng a unique distribution of type VII collagen in the nervous system.