PMID: 21613622
Authors:
Atwal JK, Chen Y, Chiu C, Mortensen DL, Meilandt WJ, Liu Y, Heise CE, Hoyte K, Luk W, Lu Y, Peng K, Wu P, Rouge L, Zhang Y, Lazarus RA, Scearce-Levie K, Wang W, Wu Y, Tessier-Lavigne M, Watts RJ
Title:
A Therapeutic Antibody Targeting BACE1 Inhibits Amyloid-{beta} Production in Vivo.
Journal:
Sci Transl Med. 2011 May 25;3(84):84ra43.
Abstract:
Reducing production of amyloid-beta (Abeta) peptide by direct inhibition of the enzymes that process amyloid precursor protein (APP) is a central therapeutic strategy for treating Alzheimer's disease. However, small-molecule inhibitors of the beta-secretase (BACE1) and gamma-secretase APP processing enzymes have shown a lack of target selectivity and poor penetrance of the blood-brain barrier (BBB). Here, we have developed a high-affinity, phage-derived human antibody that targets BACE1 (anti-BACE1) and is anti-amyloidogenic. Anti-BACE1 reduces endogenous BACE1 activity and Abeta production in human cell lines expressing APP and in cultured primary neurons. Anti-BACE1 is highly selective and does not inhibit the related enzymes BACE2 or cathepsin D. Competitive binding assays and x-ray crystallography indicate that anti-BACE1 binds noncompetitively to an exosite on BACE1 and not to the catalytic site. Systemic dosing of mice and nonhuman primates with anti-BACE1 resulted in sustained reductions in peripheral Abeta peptide concentrations. Anti-BACE1 also reduces central nervous system Abeta concentrations in mouse and monkey, consistent with a measurable uptake of antibody across the BBB. Thus, BACE1 can be targeted in a highly selective manner through passive immunization with anti-BACE1, providing a potential approach for treating Alzheimer's disease. Nevertheless, therapeutic success with anti-BACE1 will depend on improving antibody uptake into the brain.