title: Proteomic analysis of plasma from Portuguese patients with familial amyotrophic lateral sclerosis.
abstract: In ALS, the identification of abnormal proteins in biological fluids might be useful for the understanding of the ethiopathogenesis of the disease. Furthermore, it can provide biomarkers useful for diagnosis, to monitor disease progression and to study the effect of drugs. Plasma is a suitable fluid for screening such targets since blood collection is a relatively simple procedure. In this study, proteomic techniques consisting of two-dimensional gel electrophoresis and matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF MS) have been used for the analysis of plasma from a group of Portuguese familial ALS (FALS) patients not carrying SOD1 mutations, age-matched healthy controls, sporadic ALS patients and controls with other muscular disorders. Most relevant was the finding in the FALS patients of an isoform of vitamin D-binding protein (DBP) at pI 5.2, identified as GC2 by liquid chromatography electrospray ionization-TOF MS. GC2 was absent from the healthy controls. Concomitantly, decrease of more acidic isoforms of DBP was observed for the FALS patients. The results suggested that the GC2 polymorphism of DBP could constitute a risk factor for ALS.
authors.affiliation: Laboratory of Glycobiology, Instituto de Tecnologia Química e Biológica, Oeiras, Portugal.
authors.forename: Angelina S
authors.initials: AS
authors.lastname: Palma
authors.forename: Mamede
authors.initials: M
authors.lastname: De Carvalho
authors.forename: Nicolas
authors.initials: N
authors.lastname: Grammel
authors.forename: Susana
authors.initials: S
authors.lastname: Pinto
authors.forename: Nuno
authors.initials: N
authors.lastname: Barata
authors.forename: Harald S
authors.initials: HS
authors.lastname: Conradt
authors.forename: Jlia
authors.initials: J
authors.lastname: Costa
mesh_terms: D000328:Adult; D000368:Aged; D000595:Amino Acid Sequence; D000690:Amyotrophic Lateral Sclerosis / Q000097:blood* / Q000235:genetics*; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D011174:Portugal; D040901:Proteomics / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D014809:Vitamin D-Binding Protein / Q000097:blood / Q000235:genetics
chemical_list: D014809:Vitamin D-Binding Protein