Scalable Production of iPSC-Derived Human Neurons to Identify Tau-Lowering Compounds by High-Content Screening

Summary

Lowering total tau levels is an attractive therapeutic strategy for Alzheimer's disease and other tauopathies. High-throughput screening in neurons derived from human induced pluripotent stem cells (iPSCs) is a powerful tool to identify tau-targeted therapeutics. However, such screens have been hampered by heterogeneous neuronal production, high cost and low yield, and multi-step differentiation procedures. We engineered an isogenic iPSC line that harbors an inducible neurogenin 2 transgene, a transcription factor that rapidly converts iPSCs to neurons, integrated at the AAVS1 locus. Using a simplified two-step protocol, we differentiated these iPSCs into cortical glutamatergic neurons with minimal well-to-well variability. We developed a robust high-content screening assay to identify tau-lowering compounds in LOPAC and identified adrenergic receptors agonists as a class of compounds that reduce endogenous human tau. These techniques enable the use of human neurons for high-throughput screening of drugs to treat neurodegenerative disease.

Highlights

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  Inducible, isogenic, and integrated Ngn2 iPSCs were differentiated to pure neurons

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  A simple and scalable two-step protocol ensures minimal differentiation variability

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  An HCS assay was established to screen for tau-lowering compounds in LOPAC

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  AR agonists were identified as a class of compounds that reduce human tau

Abstract

Gan and colleagues developed a simple and scalable technology to generate a large quantity of homogeneous glutamatergic cortical neurons by engineering a neurogenin 2-expressing cassette to the AAVS1 locus of iPSCs. They developed a high-content screening assay and identified adrenergic receptor agonists as a class of compounds that lower endogenous human tau, a key pathogenic factor in Alzheimer's disease.