A reporter assay for target validation in primary neuronal cultures

The deposition of beta-amyloid peptides (Abeta42 and Abeta40) in neuritic plaques is one of the hallmarks of Alzheimer's disease (AD), and genes modulating their brain levels and neuronal effects could result in future disease modifying therapies. The causal association of candidate targets with AD is of paramount importance in current drug discovery, as a lack of efficacy of many candidate drugs is often due to inadequate validation of their pharmacological target. In Alzheimer's as well as in other neurodegenerative diseases, in vitro target validation is hampered by the difficulty of transfecting primary neuronal cultures and assaying the effects of genes on neuronal viability. Here we describe a rapid, sensitive and simple reporter-based assay for the validation of genes putatively associated with Abeta-mediated neurotoxicity, which can in principle be extended to the validation of targets in the context of other neuronal insults. The assay is suitable for the generation of robust and reproducible data in primary neuronal cultures allowing the dissection at a molecular level of complex pathways activated by the toxic insult in a cellular context that more closely represents the real disease situation.