Transthyretin and transferrin in hemangioblastoma stromal cells

Hemangioblastoma, a rare benign tumor of the CNS, consists of two main comp onents: capillaries and stromal cells. Despite many efforts, the histogenes is of stromal cells is still unknown. We took a new approach to clarify the origin of stromal cells using immunohistochemical methods. Paraffin-embedd ed tissue of 24 surgically removed hemangioblastomas of the CNS was examine d with antibodies against transthyretin, transferrin, vimentin, NSE, protei n S-100, CK 8, KL-1, EMA, CD34, factor VIII rAg, and collagen IV. Stromal c ells showed a positive reaction with anti-transthyretin in 12 of 24 hemangi oblastomas, a positive reaction with anti-transferrrin, to a different exte nt, in 13 of 24 cases, and many stromal cells expressed basal membrane coll agen IV on the cell surface in 19 of 24 cases. The expression of transthyre tin and transferrin in stromal cells of hemangioblastomas is reported for t he first time, thus providing an antigenic profile of hemangioblastoma stro mal cells that is very similar to that of immature choroid plexus epitheliu m. These findings support the notion that hemangioblastoma stromal cells ma y originate from the embryonal plexus epithelium. We discuss our results wi th special regard to stromal cell histogenesis, including a review of the l iterature.