Cystinosis: Selective Induction of Vacuolation in Fibroblasts by L-Cysteine-D-Penicillamine Disulfide

Abstract
In cultured fibroblasts from individuals with cystinosis vacuolation is induced by exposure to L- cysteine -D- penicillamine disulfide. Normal fibroblasts do not show vacuolation on such exposure. These observations provide direct evidence that cystinotic cells have deficient activity of a lysosomal system for disulfide metabolism or transport. Induction of vacuolation by the mixed disulfide in cystinotic but not in normal cells furnishes a histological marker for cystinotic fibroblasts.