The present invention provides methods and compositions for screening, diagnosis and prognosis of Alzheimer's disease, for monitoring the effectiveness of Alzheimer's disease treatment and for drug development. Alzheimer's disease-Associated Features (ADFs) detectable by two-dimensional electrophoresis of brain tissue are described. The invention further provides Alzheimer's disease-Associated Protein Isoforms (ADPIs) detectable in brain tissue, preparations comprising isolated ADPIs, antibodies specific for ADPIs and kits comprising the aforesaid.
