By creating a new technique to prepare specimens for examination and combining it with computational tools—including a machine learning model—Chevrier and his lab mapped gene expression across whole mouse body sections.

The system accurately mapped all organs, tissue regions, and about 75% of all known cell types in the mouse body, providing a toolkit that researchers can use to study molecular and cellular processes across the entire body of the laboratory mouse. The results, published today in Cell, could be used in both basic science research and in areas such as drug discovery.

"We now have a tool to generate datasets at a scale that was previously unimaginable," Chevrier said. "It lays a foundation to generate the kind of data which you'd need to build a 'virtual mouse' that could be used to test therapies and understand body-wide biological processes. That's the ultimate goal."

Measuring systemic inflammation across a whole body

The new technique harnesses spatial transcriptomics, which uses high-resolution microscopy and genetic sequencing to measure gene expression across tissue. This technique, optimized within the last decade, gives researchers important insight into structure and disease within an organ or tissue sample rather than in just single cells.