A rapidly dividing human medulloblastoma cell line (D283 MED) expresses all three neurofilament subunits

The majority of cells in a rapidly dividing human medulloblastoma cell line (D283 MED) are shown to express the two high-molecular-weight human neurofilament (NF) subunits, whereas a minority express the low-molecular-weight NF subunit. These three polypeptides are integral subunits of the intermediate filaments (IFs) found in normal neurons. Other cell type-specific IF proteins (keratin, desmin, and glial filament polypeptides) are not present in D283 MED cells. Further, the immunocytochemical, immunochemical and ultrastructural data suggest that the neurofilaments in these cells are abnormal, possibly because of a paucity of the low-molecular-weight NF subunit. This is the first human cell line derived from a central nervous system tumor that is capable of expressing all three NF triplet proteins. It is a unique model system for studies of normal and abnormal human NF metabolism as well as for probing the cell biology of medulloblastomas.