β-Amyloid (1-9), an N-terminal fragment of beta amyloid, consists of amino acid residues 1 to 9. β-Amyloid (1-9) contains a B cell epitope, but it does not include T cell epitopes. Omission of residues 1 to 9 from the full-length Alzheimer’sβ-Amyloid peptide 1 to 40 does not prevent the peptide from forming amyloid fibrils or eliminate fibril polymorphism .