Mount Sinai Researchers Unveil First Human Skin Spatial Atlas Mapping 1.2 Million Cells Across the Body

Researchers map 1.2 million cells across the body to create a "Google Maps" of human skin, identifying 45 cell types to help treat eczema and psoriasis.

By: AXL Media

Published: Mar 25, 2026, 9:35 AM EDT

Source: Information for this report was sourced from Mount Sinai Health System

A Cellular Blueprint of the Body’s Largest Organ

The skin serves as the primary barrier between the human body and the external environment, regulating temperature and providing critical immune protection. Despite its importance, the molecular organization of skin across different body regions has remained largely undefined until now. Mount Sinai researchers have addressed this gap by publishing the first organ-wide human skin spatial atlas. This comprehensive map reveals that healthy skin is not a uniform tissue but a complex mosaic of 45 unique cell types that vary in composition and arrangement depending on their location, from the scalp to the soles of the feet.

Discovery of Multicellular Neighborhoods

A central finding of the study is the identification of ten recurrent "multicellular neighborhoods"—biological hubs where diverse cell types prefer to be located next to one another to communicate and maintain health. One prominent example is the "perivascular neighborhood," located around the skin's blood vessels. This hub contains immune cells, such as T cells and dendritic cells, alongside specialized connective tissue cells called fibroblasts. Researchers noted that this neighborhood acts similarly to lymphoid tissues like tonsils, essentially serving as the "skin-associated lymphoid tissue" responsible for monitoring pathogens and early tumors.

Technological Breakthrough via Spatial Transcriptomics

The creation of this atlas was made possible through a cutting-edge method known as spatial transcriptomics. This technology allows scientists to profile thousands of genes while pinpointing their exact locations within individual cells. Dr. Andrew L. Ji, the study's corresponding author, compared the resolution to a smartphone map app that allows a user to zoom from a country-wide view down to a specific city block. This "bird’s-eye to genetic detail" perspective enabled the team to identify how these cellular building blocks are constructed and how their abundance shifts across 15 different anatomic sites.