SUMMARY
Brain imaging approaches are a promising method for unveiling network abnormalities in living brains of
patients with psychiatric disorders; however, understanding these pathologies will only be possible when human
specific abnormalities in cell connectivity, network circuit activity and transcriptomes can be directly interrogated
and correlated in an experimental system amenable to high-throughput manipulation and phenotyping. Despite
the excitement surrounding human brain organoids derived from pluripotent stem cells, scientists are frustrated
with the limited physiologically relevant anatomy and maturation of brain organoids.
We propose to pioneer a multi-organoid-on-chip (MoC) platform, combining tissue engineering
technologies and newer organoid analysis readouts, to address this challenge. As a first proof of concept study,
we propose to recapitulate the human visual system, a commonly affected network in multiple neuropsychiatric
disorders, by co-developing three (retinal, thalamic, cortical) organoids on a microfluidic device designed to foster
functional connectivity, thereby allowing: i) co-development of distinct central nervous system (CNS) structures
with distinct anatomical organizations; ii) establishment and mapping of reproducible and functional long-range
connectivity between defined CNS structures; iii) activity-dependent maturation of synaptic connections by
spontaneous, optogenetically-regulated, and sensory-evoked stimulation of neuronal activity. The synthetic
platform will also facilitate high-throughput multimodal analysis with direct correlation between specific circuit
connectivity and molecular dynamics at single cell resolution, in healthy and diseased organoids.
In addition to improving the understanding and screening of drugs for complex brain disorders, our
platform provides a valuable resource for the broader research community interested in modeling circuit-level
dysfunctions in other types of neurological disorders, including retinal diseases and optic neuropathy. Finally,
we expect that the method and modular technologies developed within this proposal will be foundational and
easily adapted to recapitulate connectivity between other brain regions, thereby broadening its future impact and
applications.