Detailed maps of cells in human organs show how the placenta ensures the mother’s blood supply and how kidney cells transition from a healthy to a diseased state, how cells in the intestine organize into distinct neighborhoods. Increasingly popular approach to the study of body organs in health and disease.
Each contains hundreds of thousands of data points about gene activity and protein production in individual cells, which are then mapped to their specific location in the organ.
Michael Snyder, a geneticist at Stanford University in California says “The hope is that the atlases will eventually provide clues about how to diagnose and treat disorders that can occur when these cells become injured or malfunction”.
Technologies that allow researchers to track gene activity in individual cells have helped accelerate the production of many cellular atlases in recent years, including maps of blood vessels in the brain and various types of tumors. Over time, these technologies have become more sophisticated, allowing researchers to incorporate information about a cell’s location and more closely examine gene activity.
The latest work takes this further by assessing the abundance of dozens of proteins in each cell. The research is part of a consortium called the Human Biomolecular Atlas Program (HuBMAP), which is funded by the US National Institutes of Health and aims to develop tools for mapping the cells of the human body.
In one study, researchers instead of mapping tissues in a single organ, they studied the interface between two: the placenta and the uterus. The team used data from 500,000 cells and 588 uterine arteries to learn about how fetal cells invade and remodel blood vessels in the lining of the uterus so that they become larger and better able to deliver nutrients in the later stages of pregnancy.
Errors in this process have been linked to preeclampsia and other conditions that can endanger the health of both the fetus and the mother.
Angelo’s results match well with data published earlier this year that cataloged gene activity in the cells that make up the placenta8, says Roser Vento-Tormo, a geneticist at the Wellcome Sanger Institute in Cambridge, UK.
In particular, data on the expression of 37 proteins in each cell gives researchers a high-resolution view of communication between fetal and maternal cells, he says. “If we want to look at disease, we need to deeply understand what happens in healthy conditions.”
co-author Sanjay Jain, a pathologist at Washington University School of Medicine in St Louis, Missouri says “One of the latest studies compares healthy and damaged kidney cells. We’ve been able to build pathways for cells to move from healthy to injured”.
The beauty of the studies lies not only in their direct findings, but also in how they integrated vast amounts of data, Vento-Tormo says. Researchers are also working to increase the diversity of tissue donors for cell atlas projects, he says, and to develop ways to scale up from 2D to 3D analyses.
Future studies will no doubt focus on more tissues, disease states and developmental stages, says Sarah Teichmann, a geneticist at the Sanger Institute who participates in HuBMAP. “There are a lot of other tissues and organs in the body,” he says.