Integrated platform for multi-scale molecular imaging and phenotyping of the human brain

Abstract

AbstractA detailed understanding of the anatomical and molecular architectures of cells and their system-wide connectivity is essential for interrogating system function and dysfunction. Extensive efforts have been made toward characterizing cells through various approaches, and have established invaluable databases yielding new insights. However, we still lack technologies for mapping the combined multi-scale anatomical and molecular details of individual cells in the human organ-scale system. To address this challenge, we developed a fully integrated technology platform for simultaneously extracting spatial, molecular, morphological, and connectivity information of individual cells from the same human brain at single-fiber resolution. We accomplished this by seamlessly integrating new chemical, mechanical, and computational tools to enable 3D multi-scale proteomic reconstruction of human organ tissues. We developed a novel microtome, termed MEGAtome, that enables ultra-precision slicing of whole-mount intact human brain hemispheres and large arrays of organs from other species with no loss of intra- and inter-slice cellular connectivity. To preserve structural and molecular information within intact human brain slabs and to enable multiplexed multiscale imaging, we developed a tissue-gel technology, termed mELAST, that transforms human brain tissues into an elastic and reversibly expandable tissue-hydrogel. To reconstruct the 3D connectivity of axonal networks across multiple brain slabs, we developed a computational pipeline termed UNSLICE. Using the technology platform, we analyzed Alzheimer’s disease (AD) pathology at multiple scales from overall cytoarchitecture to individual synapses. Finally, we demonstrated the feasibility of scalable neural connectivity mapping in human brain, establishing a path for probing brain connectivity and its alterations in diseases.One-Sentence SummaryWe developed an integrated scalable platform for highly multiplexed multi-scale phenotyping and connectivity mapping in the same human brain tissue, which includes novel tissue processing, labeling, imaging, and computational reconstruction technologies.