Non-infectious form of prion protein could cause brain degeneration. Prion proteins may react with amyloid-(beta) peptides inside the brain cells of Alzheimer's patients.Thomas Deerinck NCMIR/Science Photo Library Non-infectious prion proteins found in the brain may contribute to Alzheimer's disease, researchers have found. The surprising new results, reported this week in Nature1, show that normal prion proteins produced naturally in the brain interact with the amyloid-(beta) peptides that are hallmarks of Alzheimer's disease. Blocking this interaction in preparations made from mouse brains halted some neurological defects caused by the accumulation of amyloid-(beta) peptide. It was previously thought that only infectious prion...