High-content imaging of live microglia-containing Alzheimer's disease brain organoids

Alzheimer's disease (AD) is the most common progressive neurodegenerative disease for which there is currently no safe and effective treatment. AD is characterized by the pathological aggregation of amyloid-β (Aβ) in the brain resulting in neuronal dysfunction/death and cognitive decline. Modeling these processes in vitro remains challenging due to the lack of an immune-competent 3D in vitro human model of AD amenable to high-throughput analyses. Conventional cerebral organoids (COs) lack microglia and are optically dense which precludes real-time longitudinal analyses. Here, we employ the fluorescent amyloid probe PyrPeg to selectively monitor Aβ aggregation, and calcein AM and propidium iodide to assess cellular viability within microglia-containing COs (MCOs). We identify age-dependent DS-AD-associated phenotypes within T21 MCOs including Aβ neuropathology, neurodegeneration, and glial cell dysregulation. Our platform supports real-time, multiplexed tracking of disease progression and provides a scalable platform for longitudinal analyses studying disease mechanisms and targeted approaches to treatment.