EVIDENCE OF ABNORMAL DIFFERENTIATION IN GIANT-CELLS OF TUBEROUS SCLEROSIS

To characterize the giant cells in tuberous sclerosis, we examined imm unoreactivity for nestin, vimentin, microtubule-associated protein 1B (MAP1B), MAP2, neurofilament, and glial fibrillary acidic protein (GFA P) in cortical tubers detected in brain specimens from 6 patients with tuberous sclerosis who had undergone surgical resection for treatment of intractable epilepsy, Giant cells with a neuronal appearance, ''ne uron-like giant cells,'' had a round centrally-placed nucleus with a s ingle, prominent nucleolus, and Nissl substance was commonly present i n cortex, These neuron-like giant cells demonstrated consistently stro ng immunoreactivity for neurofilament and MAP1B and occasional immunop ositivity for nestin and vimentin and were rarely positive for GFAP, ' 'Indeterminate giant cells,'' characterized by abundant cytoplasm, an absence of Nissl substance, and one or more eccentric nuclei, demonstr ated consistent immunoreactivity for nestin, vimentin, and MAP1B and w ere rarely positive for neurofilament, but more than half displayed im munoreactivity for GFAP, These observations suggest that the indetermi nate giant cells exhibit limited neuronal and inconsistent astroglial characteristics, implying aberrant cellular differentiation in tuberou s sclerosis, (C) 1997 by Elsevier Science Inc, All rights reserved.