A Digital Atlas of Human Ultrastructure.

Electron microscopy (EM) is the method to visualize the building blocks of life in organs and tissues at biomolecular resolution. The resulting ultrastructural information directly reveals information about function and health status. For decades, a challenge has been to create and share panoramic EM, providing ultrastructural overviews of tissues at high resolution. However, the breakthrough came with the digital revolution that enabled large fields-of-view to be acquired automatically resulting in datasets several orders of magnitude larger than a single micrograph. Browser-based viewing of the resulting zoomable datasets now allows anyone across the globe to explore cellular ultrastructure at scale. Though now routinely applied in specific studies of disease, reference images for the ultrastructure of cells and tissues typically remain to be of small fields-of-view and thereby lack the context of the surrounding tissue. Here, we present a digital reference atlas (https://www.nanotomy.org/OA/HumanAtlas/) of human ultrastructure of twelve different organs. Like other repositories the collection will grow over time with more organs as well as disease states enabling scientists to address different aspects in EM data that is now just a mouse-click away.