High density lipoproteins bind Aβ and apolipoprotein C-II amyloid fibrils
2006
Leanne M. Wilson | Chi L.L. Pham | Alicia J. Jenkins | John D. Wade | Andrew F. Hill | Matthew A. Perugini | Geoffrey J. Howlett
Disease-associated amyloid deposits contain both fibrillar and nonfibrillar components. The majority of these amyloid components originate or coexist in the bloodstream. To understand the nature of the interaction between the nonfibrillar and fibrillar components, we have developed a centrifugation method to isolate fibril binding proteins from human serum. Amyloid fibrils composed of either Aβ peptide or apolipoprotein C-II (apoC-II) cosedimented with specific serum proteins. Gel electrophoresis, mass spectrometry peptide fingerprinting, and Western analysis identified the major binding species as proteins found in HDL particles, including apoA-I, apoA-II, apoE, clusterin, and serum amyloid A. Sedimentation analysis showed that purified human HDL and recombinant apoA-I lipid particles bound directly to Aβ and apoC-II amyloid fibrils. These studies reveal a novel function of HDL that may contribute to the well-established protective effect of this lipoprotein class in heart disease.
显示更多 [+] 显示较少 [-]