REAGENTS/MATERIAL: Polyclonal antibody R1282 was used to IP Abeta from cells. Western blots were probed with monoclonal 2G3 (1 ug/ml) raised to amyloid-beta (33−40) which specifically recognizes amyloid-beta species ending at residue 40; (gift of P. Seubert and D. Schenk, Elan Pharmaceuticals) and monoclonal 6E10 1ug/ml.