Amyloid β-protein ending at Thr43 is a minor component of some diffuse plaques in the Alzheimer's disease brain, but is not found in cerebrovascular amyloid

The distribution of amyloid β-protein ending at 40 (Aβ40), 42 (Aβ42), and 43 (Aβ43) were immunocytochemically examined in Alzheimer's brains. A large number of diffuse plaques were stained with Aβ42 antibody (S42), but some were weakly labeled with Aβ43 antibody (S43). Immature and mature plaques were labeled with Aβ40 antibody (S40), S42, and S43. Thus, A,β42 is the major component of diffuse plaques, the initial phase of plaque formation, and Aβ43 is present as a minor component. Only Aβ40 is present in cerebrovascular amyloid.