title: Abnormal and deficient processing of beta-amyloid precursor protein in familial Alzheimer's disease lymphoblastoid cells.
abstract: Western blot analysis showed abnormal processing of beta-amyloid precursor protein (APP) in lymphoblastoid cell lines (LCLs) of familial Alzheimer's disease (FAD). Antibody raised against central APP751 revealed that media of early and late-onset FAD LCLs had highly increased amounts of a 120 kD long-lived. SDS-stable, heat-labile complex of the Kunitz protease inhibitor domain of secreted APP and a approximately 70 kD FAD-specific, yet unidentified serine protease. Antibody against the beta A4-cytoplasmic domain showed a slower APP processing and increased amounts of 16 kD C-terminal preamyloid in lysates of early and late-onset FAD LCLs, first indicating a deficient intra-beta A4 proteolysis in FAD as a possible cause of abundant amyloid deposits in AD brain.
authors.affiliation: Department of Radiation Biophysics, Kobe University School of Medicine, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Matsumoto
authors.forename: Y
authors.initials: Y
authors.lastname: Fujiwara
mesh_terms: D000544:Alzheimer Disease / Q000378:metabolism*; D016229:Amyloid beta-Peptides / Q000737:chemistry / Q000378:metabolism*; D016564:Amyloid beta-Protein Precursor; D002478:Cells, Cultured; D006801:Humans; D066298:In Vitro Techniques; D008214:Lymphocytes / Q000378:metabolism; D008970:Molecular Weight; D011498:Protein Precursors / Q000737:chemistry / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D016229:Amyloid beta-Peptides; D016564:Amyloid beta-Protein Precursor; D011498:Protein Precursors; D011994:Recombinant Proteins