Serum Amyloid A Peptide Interactions with Glycosaminoglycans: Evaluation by Affinity Chromatography

Amyloid is a pathological deposit of protein and glycosaminoglycans (GAGs) that can lead to the destruction of tissue architecture and function (1,2). To date, 18 unrelated proteins are known precursors of amyloid deposits (3). Each one is associated with a specific disease, such as Alzheimer’s disease, adult-onset diabetes, inflammatory disorders, and some cancers, but regardless of the type of precursor protein involved, all amyloids have common tinctorial and structural characteristics. Fibrils are composed of two or more filaments 3 nm in diameter twisted around each other forming nonbranching fibrils 7–10 nm in diameter with a crossed β-pleated sheet conformation. Congo red stains these deposits, and when viewed under polarizing light they exhibit a red/green birefringence characteristic™ for amyloid.