New Single-Cell Immune Atlas Offers a Framework for Studying the Developing Immune System

Collaboration between research teams at Nationwide Children’s Hospital, Washington University in St. Louis, and King’s College London has created a large-scale single-cell map of the human immune system that could provide an important framework for studying how immunity develops throughout life.

Their findings are published in Immunity. The researchers, including co-corresponding authors Maxim N. Artyomov, PhD, the Alumni Endowed Professor of Pathology and Immunology at WashU Medicine, Stephen Harridge, PhD, a professor of human and applied physiology at King’s College London, and Mykyta Artomov, PhD, an assistant professor at the Steve and Cindy Rasmussen Institute for Genomic Medicine at Nationwide Children’s Hospital, set out to understand how people’s immune systems age. They analyzed approximately 12.4 million individual immune cells from the blood of 2,609 mainly healthy adults ages 20 to 90-plus across eight cohorts in North America, the United Kingdom, Asia and Australia. Using a harmonized annotation approach, researchers identified 59 distinct immune cell populations, enabling consistent comparison of highly specific cell states across large and diverse datasets.

The study demonstrates the importance of a high-resolution approach by distinguishing closely related CD8+ T-cell populations representing different stages of differentiation — populations that conventional classification approaches cannot reliably separate.

Mykyta Artomov, PhD

“Our lab focuses on developing predictive models that help identify individuals at risk of developing disease. What excited us about this project was the opportunity to connect detailed information about individual immune cell populations to long-term health outcomes. By analyzing blood protein profiles from nearly 50,000 UK Biobank participants, we were able to identify molecular signatures of specific immune cell types and link them to the risk of developing multiple diseases. This approach demonstrates how fundamental discoveries in immunology can be translated into tools for predicting disease risk, with potential applications across the lifespan, including pediatric populations,” says Dr. Mykyta Artomov.

While the paper focused on adult data, connecting changes in the immune system to aging and the high-resolution approach for cell type annotations has particular relevance for pediatric research.

Throughout childhood and adolescence, the immune system undergoes substantial development, and many cells exist in transitional states that can be difficult to distinguish using conventional immune-cell classifications.

“Children are not simply smaller adults; their immune systems are actively developing,” Dr. Mykyta Artomov explains. “The ability to robustly identify intermediate immune-cell states gives a powerful framework for understanding normal immune development and how that process may be altered in pediatric disease.”

The researchers also made the harmonized dataset publicly available, providing a reference resource that can support future studies of immune development, disease and health across the lifespan.

Reference:

Terekhova M, Kleverov M, Francis T, Usoltsev D, Bohacova P, Arthur L, Tsurinov P, Kleverov D, Trinity L, Husarcikova K, Molotkov I, Grabauskas T, Fathi A, Milbourn E, Newton E, Siegel L, Ghanchi A, Tse U, Pollock RD, Duggal NA, Lord JM, Lazarus NR, Ellebedy AH, Ucar D, Harridge SDR, Artomov M, Artyomov MN. Single-cell analyses of global cohorts outline determinants of immune aging and link the ratio of GZMK⁺ to GZMB⁺ Tem cells to health trajectories. Immunity. October 9, 2026.

Image credit: Nationwide Children’s (portrait)