New Study Identifies Immune Trigger Behind Radiation-Related Lung Damage
Findings from a preclinical investigation point to a possible strategy for reducing a serious side effect of cancer care
LOS ANGELES, October 20, 2026--Researchers at City of Hope®, one of the largest and most advanced cancer research and treatment organizations in the country, have uncovered an immune pathway that may contribute to radiation-related lung damage and have identified a potential strategy to block it. Published today in Nature Communications, the insights from the preclinical study could lead to new treatments that prevent radiation from harming healthy lung tissue and improve patients' quality of life.
Some 230,000 Americans are diagnosed with lung cancer each year, and up to 70% of people diagnosed with the disease will undergo radiation at some point in their treatment. While radiation is often lifesaving, the therapy can permanently damage healthy lung tissue and limit future cancer treatment options.
When healthy lung tissue is damaged, the effects can be severe and long-lasting. Up to 20% of patients struggle with debilitating breathing difficulties and reduced quality of life, leaving some patients tethered to heavy oxygen tanks.
Radiation Reprograms Rare but Important Immune Cells
"Many researchers in our field study how radiation activates well-known immune cells such as T cells to fight cancer," said corresponding author Heather McGee, M.D., Ph.D., an assistant professor in the departments of radiation oncology and immuno-oncology at City of Hope. "We are the first group to show that radiation also reprograms rare immune cells called innate lymphoid cells, and that these cells play a key role in driving damage to healthy lung tissue."
Dr. McGee leads a team of scientists investigating the role innate lymphoid cells play in the response to radiation. To better understand how radiation damages healthy lung tissue, her laboratory developed a mouse model of radiation-induced lung injury.
Using advanced techniques to track radiation's impact on the immune system, her team observed three key findings.
First, radiation provoked a dramatic transformation in innate lymphoid cells (ILCs), causing them to adopt different identities and alter their functions. One type of ILC, called ILC2s, helps protect the lungs from damage. Radiation transformed these cells into another type, called ILC1s, which promotes inflammation that damages healthy lung tissue.
Second, the researchers discovered what drives this transformation. Radiation increased levels of a signaling protein called interferon-beta (IFN-beta), which acted as the switch that pushed protective ILC2 cells to become inflammatory ILC1 cells. Tests on human ILCs showed similar biological changes.