The complexity of the mammalian brain is unparalleled by any other organs, and understanding its cellular
composition and their brain-wide organization is essential to understand the brain functions and dysfunctions.
Extensive efforts have been made toward mapping brain cells through various lenses, and have established
invaluable databases yielding new insights. However, only a few molecules, or cell-types, or regions per brain
have been mapped in non-human primate and human brains, and fail to capture brain-wide complex intercellular
relationships within individuals. We here aim to develop versatile and easy-to-adopt platform technologies for
highly multiplexed, rapid, scalable proteomic mapping of mammalian brains from mouse, marmoset, to human.
We propose to (Aim 1) develop molecular toolkits and platform technologies (ELAST-SABER) for highly
multiplexed scalable proteomic phenotyping of mouse, marmoset, human brains. We will develop a library of
orthogonal DNA-barcoded antibodies targeting over 100 canonical cell-type markers, compatible with SABER
amplification (developed by the group of PI Peng Yin) and ELAST transport (developed by the group of PI
Kwanghun Chung). We will also (Aim 2) validate the technology platform and demonstrate its broad utility and
scalability by mapping the cellular landscape in the primary motor cortex (M1) of mouse, marmoset, human
brains including tissues with amyotrophic lateral sclerosis (ALS) pathology. We will cross-validate our method
using the published MERFISH and single-cell sequencing data from BICCN. We will perform cross-species
comparative analysis to understand conserved or evolutionarily distinct cellular features of M1. Finally, we will
(Aim 3) establish web-based interactive platforms for data dissemination and community use. We will build
multimodal brain atlases allowing cross species comparison, and develop neuro-ontology of the mouse,
marmoset and human brain. Importantly, we will develop a database built with informatics and online
visualization tools that allow people to view, compare, and analyze multiplexed scalable proteomic imaging data
across three species. These informatics tools will have the capacity to standardize and accommodate histological,
connectivity, gene expression, and in vivo imaging. Users will be able to compare multi-modality data for the
“most comparable structures” either based on their neuroanatomic nomenclature, ontology relationship, similarity
of their protein markers, or neural connectivity. These tools will become openly available to the community. Our
technology platform will enable us to establish the most comprehensive 3D map of the primary motor cortex (M1)
of marmoset and human brains including tissues with amyotrophic lateral sclerosis (ALS) pathology to date—
providing a foundation for mapping cell types brain-wide in the future and for studying pathological changes in
brain disorders. We envision that these scalable tools will empower the research community to interrogate brain
structure and function, including complex intercellular relationships at multiple scales.