title: Fibroblast immuno-diagnosis of cytochrome oxidase (COX) deficiency in mitochondrial disease.
abstract: We studied cytochrome c oxidase (COX) expression patterns in nuclear and mtDNA gene defects. Using quantitative immunocytochemical assay for COX, heteroplasmic staining was seen in MELAS patients with mtDNA mutations but similar staining variability was seen in control cell lines and nuclear gene defects. All fibroblast lines showed a wide variability in cell-to-cell COX I staining intensity. All 8 patient fibroblast lines had reduced COX staining on immunocytochemistry. In 6 lines reduced protein amount was seen on Western blotting and 7 had low COX activity. This study demonstrates that nuclear gene defects can produce a heteroplasmic appearance on immunocytochemistry.
authors.affiliation: Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China.
authors.forename: Ailian
authors.initials: A
authors.lastname: Du
authors.forename: Robert K
authors.initials: RK
authors.lastname: Naviaux
authors.forename: Thuy
authors.initials: T
authors.lastname: Le
authors.forename: Congfeng
authors.initials: C
authors.lastname: Xu
authors.forename: Steven S
authors.initials: SS
authors.lastname: Sommer
authors.forename: Richard H
authors.initials: RH
authors.lastname: Haas
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015153:Blotting, Western; D019411:Clinical Laboratory Techniques / Q000379:methods*; D030401:Cytochrome-c Oxidase Deficiency / Q000175:diagnosis*; D003576:Electron Transport Complex IV / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000201:enzymology* / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008875:Middle Aged; D028361:Mitochondrial Diseases / Q000175:diagnosis*; D013194:Staining and Labeling / Q000379:methods; D055815:Young Adult
chemical_list: D003576:Electron Transport Complex IV