Patent ID: 7427392

Claim:
A method for screening a compound to determine its ability to alter the amount of an Aβ(x−≧41) peptide in a cerebral spinal fluid sample comprising: measuring a first amount of one or more soluble Aβ(x−≧41) peptides in the cerebral spinal fluid sample of a non-human animal model that expresses amyloid-β precursor protein (APP) in the brain and processes it to the one or more soluble Aβ peptides; administering the compound to the non-human animal model; measuring a second amount of the one or more soluble Aβ peptides in the cerebral spinal fluid sample of the non-human animal model; and comparing the first amount with the second amount, the difference indicating whether the compound increases, decreases, or leaves unchanged the amount of soluble Aβ(x−≧41) in the cerebral spinal fluid sample, wherein the amount of Aβ(x−≧41) is measured by exposing the cerebral spinal fluid to an antibody or fragment thereof specific for an epitope of Aβ(x−≧41) but that does not cross react with an epitope of Aβ(x−≦40).