A cell-based method for the detection of nanomolar concentrations of bioactive amyloid.
A cell-based method for the detection of nanomolar concentrations of bioactive amyloid peptide is described. The method is based upon the observation that fibrillogenic amyloid peptides specifically and dramatically enhance the exocytosis of the intracellular vesicles that are involved in transporting the reduced tetrazolium dye 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT formazan), with the formation of unique formazan crystals on the cell surface. It is found that the ability of amyloid peptides to induce MTT formazan exocytosis is closely associated with both their neurotoxicity and their ability to activate glia cells, two biological activities of amyloid peptides that are believed to cause neurodegeneration. This simple assay for bioactive amyloid species can be of great value in the screening of anti-amyloid drugs and in the study of amyloid fibrillogenesis with a cell-based model.
Liu
Y
Y
Cellular Neurobiology Laboratory, The Salk Institute for Biological Studies, 10010 Torrey Pines Road, La Jolla, CA 92037-1099, USA. liu@salk.edu
Piasecki
D
D
D000682:Amyloid / Q000032:analysis*; D000818:Animals; D001253:Astrocytes / Q000378:metabolism; D002478:Cells, Cultured; D003224:Congo Red / Q000494:pharmacology; D004353:Drug Evaluation, Preclinical; D005089:Exocytosis; D005562:Formazans / Q000494:pharmacology; D006624:Hippocampus / Q000166:cytology; D008854:Microscopy, Electron; D008856:Microscopy, Fluorescence / Q000379:methods*; D009457:Neuroglia / Q000187:drug effects; D009474:Neurons / Q000378:metabolism; D010455:Peptides / Q000032:analysis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013778:Tetrazolium Salts / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D000682:Amyloid; D005562:Formazans; D010455:Peptides; D013778:Tetrazolium Salts; C079782:MTT formazan; D003224:Congo Red