Cystinuria and cystinosis are usually related to L-cystine: is this really the case for cystinosis? A physicochemical investigation at micrometre and nanometre scale

Intralysosomal cystine crystals in cystinosis.

Electron microscopic study of conjunctival biopsies from members of one sibship each of nephropathic and benign cystinosis showed polymorphic cystine profiles abundantly distributed in fibroblasts and histiocytes. These crystalline spaces measured from 0.2(i to 2/i and were delineated marginally by intact cellular membranes. Small crystalline aggregates were found in acid-phosphatase-positive o...

ATP-dependent lysosomal cystine efflux is defective in cystinosis.

Lysosomes containing large amounts of the amino acid, cystine, were obtained from transformed, cultured, human lymphoblasts which had been exposed to cystine dimethyl ester. Lysosomal cystine efflux was greatly enhanced by exogenous ATP in cell lines from normal individuals. Cystine efflux was unresponsive to ATP in lysosomes from individuals with the disorder, cystinosis. Efflux of cystine fro...

Cystinosis.

The pathogenesis of cystinosis: mechanisms beyond cystine accumulation.

Renal proximal tubules are highly sensitive to ischemic and toxic insults and are affected in diverse genetic disorders, of which nephropathic cystinosis is the most common. The disease is caused by mutations in the CTNS gene, encoding the lysosomal cystine transporter cystinosin, and is characterized by accumulation of cystine in the lysosomes throughout the body. In the majority of the patien...

Cystine storage in cultured myotubes from patients with nephropathic cystinosis.

Sorted muscle cells, cultured from a patient with nephropathic cystinosis, stored 100 times normal amounts of cystine. Subcellular fractionation and density-gradient centrifugation confirmed that the cystine was located in a lysosomal compartment. 2. Myoblasts from cystinotic patients in culture underwent fusion to myotubes in a normal fashion. 3. The free thiol cysteamine effectively depleted ...