Use of Dithiothreitol to Correct Cystine Storage in Cultured Cystinotic Fibroblasts

Cystinosis. Intracellular cystine depletion by aminothiols in vitro and in vivo.

“…2. The values for DTT agree with previous studies (4,5). At a concentration of 1 mM, cystamine, the disulfide of cysteamine, is equally as effective as cysteamine in producing intracellular nonprotein cystine depletion from cystinotic fibroblasts.…”

“…Effective methods include growth in a lowcystine medium (3), treatment with dithiothreitol (DTT)' (4,5), and treatment with ascorbic acid (6). None of these methods has been proved effective clinically, although DTT treatment has been shown to lower the leukocyte nonprotein cystine content in vivo (7).…”

Biochemical, Morphologic, and Gytogenetic Studies of Leukocytes Growing in Continuous Culture from Normal Individuals and from Patients with Cystinosis

“…Clinical variants of lesser severity have been recognized [9,19,22,31]. Cystinotic tissues contain large excesses of cystine, which are often visible in appropriately prepared tissues as intracellular crystalline deposits.…”

Depletion of Cystine in Cystinotic Fibroblasts by Drugs Enclosed in Liposomes

“…Reasons for these increases are not apparent; the result with D m was particularly surprising since others have shown (7) and we have confirmed that this drug will deplete the cystine content of cystinotic cells under different conditions. Vitamin C and DTT are known to decrease the storage of cystine in cystinotic cells when used in repeated doses over longer periods of time (7,15).…”

“…Vitamin C does not reduce cystine directly and its mechanism of cystine depletion is obscure. Goldman et al (7) and Aaron et al (1) were able to deplete intracellular cystine in cystinotic fibroblasts by the use of the reducing agent, DTT. These results were subsequently confirmed in our laboratory under the conditions they described.…”