ANTIBODIES TO HUMAN BRAIN SPECTRIN IN ALZHEIMERS-DISEASE

We investigated the existence of antibodies in sera of Alzheimer's dis ease patients which immunoreact with specific antigens from crude huma n brain extracts. We found that 49% of patients, per only 5% of contro l subjects, had increased levels of antibodies to a 240 kDa protein. O n the basis of immunological criteria and internal aminoacid sequencin g, this antigen was identified as brain spectrin, a cytoskeletal prote in which appears to be implicated in synaptic plasticity. Our data rai ses the possibility that anti-spectrin antibodies could be implicated in Alzheimer's disease pathogenesis.