DEFICIENT FERRITIN IMMUNOREACTIVITY IN VISCERAL ORGANS FROM 4 PATIENTS WITH NIEMANN-PICK DISEASE TYPE-C

Ferritin, the major iron storage protein, was found to be undetectable on immunoblot analysis of spleen and liver extracts from four patient s with Niemann-Pick disease type C (NPC). The patients had died from d ifferent clinical forms of this storage disease of still unknown etiol ogy. The absence of ferritin immunoreactivity was shown using two diff erent antisera, raised in rabbits, against ferritin from human spleen containing predominantly light-chain subunits (L-ferritin). Further ev idence of absent L-ferritin in visceral tissues was provided by immuno histochemical studies performed in one of the four NPC patients, Howev er, heavy-chain and light-chain ferritin mRNAs could be identified in cultured fibroblasts from this patient, The finding of deficient ferri tin immunoreactivity is suggestive of an additional biochemical abnorm ality that is as marked as the known impairment of the transport of ex ogenously derived cholesterol in this complex lysosomal storage disord er. (C) 1995 Academic Press, Inc.