Inhibitory effect of monoclonal antibodies on Alzheimer's beta-amyloid peptide aggregation

In vitro aggregation of beta-amyloid peptide induced by incubating the peptide for 3 h at 37 degrees C, was investigated via immunocomplexation with a panel of monclonal antibodies raised against various beta-amyloid fragments. Some of these monoclonal antibodies prevented the formation of beta-amyloid and this effect may be related to the localization of the antibody binding sites. Monoclonal antibodies 6C6 and 10D5, and AMY-33, which recognize epitopes spanning the amino acid residues 1-28 of beta-amyloid peptide, inhibited its aggregation by 40%-90% when compared with aggregation occurring in the absence of the respective antibodies. The antibodies, 2H3 and 1C2, directed to the regions comprising peptides 1-12 and 13-28, respectively, had a considerable low effect. Identifying the ''aggregating epitopes'' as sequences that are related to the sites where protein aggregation is initiated and preparing monoclonal antibodies against these regions may facilitate the understanding against these regions may facilitate the understanding and prevention of protein aggregation process. This study may provide a factual basis for using monoclonal antibodies to prevent the beta-amyloid formation that is associated with Alzheimer's disease.