New Method for Determining Cystine in Leukocytes and Fibroblasts

Cystinosis is a rare inborn error of cystine transport, leading to accumulation of cystine in the lysosomes. To diagnose cystinosis and monitor treatment with cysteamine, adequate measurements of cystine concentrations in leukocytes and cultured fibroblasts are required. Cells were sonicated in the...

Full description

Saved in:
Bibliographic Details
Published in:Clinical chemistry (Baltimore, Md.) Md.), 1999-12, Vol.45 (12), p.2224-2228
Main Authors: de Graaf-Hess, Adriana, Trijbels, Frans, Blom, Henk
Format: Article
Language:English
Subjects:
Adult
Aminoacid disorders
Biological and medical sciences
Borohydrides
Bridged Bicyclo Compounds
Cell Extracts - chemistry
Chromatography, High Pressure Liquid - methods
Cysteamine - therapeutic use
Cystine - analysis
Cystine - blood
Cystinosis - diagnosis
Cystinosis - drug therapy
Errors of metabolism
Ethylmaleimide
Fibroblasts - metabolism
Fluorometry
Humans
Investigative techniques, diagnostic techniques (general aspects)
Leukocytes - metabolism
Medical sciences
Metabolic diseases
Middle Aged
Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques
Reproducibility of Results
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Cystinosis is a rare inborn error of cystine transport, leading to accumulation of cystine in the lysosomes. To diagnose cystinosis and monitor treatment with cysteamine, adequate measurements of cystine concentrations in leukocytes and cultured fibroblasts are required. Cells were sonicated in the presence of excess N-ethylmaleimide to prevent oxidation of cysteine to cystine and disulfide exchange reactions of cystine with available sulfhydryl moieties. Cystine was measured as cysteine after reduction with sodium borohydride and derivatization with monobromobimane, followed by separation with automated HPLC and fluorescence detection. The assay was linear to 200 micromol/L cysteine. Within-run and day-to-day (total) imprecision (CV) was
ISSN:0009-9147
1530-8561
DOI:10.1093/clinchem/45.12.2224