Total α-synuclein levels in human blood cells, CSF, and saliva determined by a lipid-ELISA.
The validity of α-synuclein (α-Syn) as a biomarker for Parkinson's disease (PD) is still under investigation. Conventional methods for capture and quantitation of α-Syn protein in human samples are primarily based on anti-α-Syn antibodies. Specific and competent antibodies were raised against α-Syn. However, capture by anti-α-Syn antibodies may be limited to specific epitope recognition, attributed to protein structure or post-translational modifications. Hence, antibody-based methods for α-Syn capture raise a concern regarding their efficacy to detect the intracellular, unfolded α-Syn pool. An alternative is α-Syn capture by membrane lipids, i.e., to utilize the biochemical property of α-Syn to specifically bind membrane lipids and acquire a characteristic structure following binding. We determined α-Syn levels in human samples using immobilized lipids for α-Syn capture. The lipids used for α-Syn capture consist of phosphatidyl inositol (PI), phosphatidyl serine (PS), and phosphatidyl ethanolamine (PE). Addition of mono-sialoganglioside, GM1 ganglioside, to the immobilized lipids significantly improved α-Syn detection. Following capture, the lipid-bound α-Syn was detected using an anti-α-Syn antibody. Total α-Syn levels in whole blood cells (WBC), cerebrospinal fluid (CSF), and saliva were determined by the lipid-ELISA method.
Biochemistry and Molecular Biology, IMRIC, The Hebrew University-Hadassah Medical School, Ein Kerem, 91120, Jerusalem, Israel.
Suaad
S
Abd-Elhadi
Department of Anesthesia, Hospital Clinic of Barcelona, Carrer de Villaroel 170, 08036, Barcelona, Catalonia, Spain.
Misericordia
M
Basora
Parkinson's Disease and Movement Disorders Unit, Neurology Service, Institute de Neurociències Hospital Clínic, University of Barcelona, Carrer de Villaroel 170, 08036, Barcelona, Catalonia, Spain.
Dolores
D
Vilas
Parkinson's Disease and Movement Disorders Unit, Neurology Service, Institute de Neurociències Hospital Clínic, University of Barcelona, Carrer de Villaroel 170, 08036, Barcelona, Catalonia, Spain.
Eduardo
E
Tolosa
Biochemistry and Molecular Biology, IMRIC, The Hebrew University-Hadassah Medical School, Ein Kerem, 91120, Jerusalem, Israel. ronitsh@ekmd.huji.ac.il.
Ronit
R
Sharon
D000328:Adult; D000906:Antibodies / Q000737:chemistry; D001773:Blood Cells / Q000737:chemistry; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D005677:G(M1) Ganglioside / Q000378:metabolism; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000097:blood* / Q000134:cerebrospinal fluid* / Q000175:diagnosis; D010714:Phosphatidylethanolamines / Q000378:metabolism; D010716:Phosphatidylinositols / Q000378:metabolism; D010718:Phosphatidylserines / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D017510:Protein Folding; D012463:Saliva / Q000737:chemistry; D051844:alpha-Synuclein / Q000097:blood / Q000134:cerebrospinal fluid
D000906:Antibodies; D010714:Phosphatidylethanolamines; D010716:Phosphatidylinositols; D010718:Phosphatidylserines; D010743:Phospholipids; D051844:alpha-Synuclein; D005677:G(M1) Ganglioside; C483858:phosphatidylethanolamine
Biomarkers; ELISA; Parkinson’s disease; Phospholipids; α-Synuclein