β-Amyloid 22-35 (Amyloid β-Protein 22-35) TFA, the residues 22-35 fragment ofβ-amyloid protein, has a cytotoxic effect on cultured neurons from the rat hippocampus in serum-free medium. β-Amyloid 22-35 TFA forms aggregates and typical amyloid fibrils resembling those of the β-amyloid protein in neutral buffer solution).In Vitro: β-Amyloid 22-35 (Amyloid β-Protein 22-35) TFA shows significant cytotoxicity on the rat hippocampal neurons at 40 μg/mL, but exhibits no cytotoxic effect on the glial cells.