Some cases of the flu are so severe they cause lasting injury to the lungs. New research from the University of Pennsylvania now points to a strategy that may one day offer protection against this damage.

The scientists found that transplanting a certain type of lung cell from healthy mice to those that had been injured by an infection with influenza could improve healing. The transplant—achieved by taking specialized lung cells called alveolar type-two (AT2) cells from the healthy animals and then allowing the sick animals to simply breathe in the cells—led to improved blood-oxygen levels.

“We took this really simple approach,” says Andrew Vaughan, senior author on the paper and an assistant professor in Penn’s School of Veterinary Medicine, “and asked if we could supplement back these AT2 cells into injured mice, can we make them better, can we improve lung regeneration?”

“Imagine if this were in humans,” adds Aaron Weiner, lead author on the study and a graduate student in Vaughan’s lab. “If there were a bad flu season coming up, it could be routine to say, can you take some of my AT2 cells, grow them up for me, and if I get sick you can just put them back in to help me recover. That biobank idea is what we’re imagining.”

The study appears in the journal Regenerative Medicine.