Joanna Smeeton, a USC scientist and Canadian, has seen the effects of brutally cold winters on people with arthritis. She explores stem cell–based approaches to studying – and eventually treating – the common cause of cold aversion, disability and pain.

“We only have treatments for the larger joints where you can provide total replacements, but a lot of people with arthritis actually get it in the joints of their hands,” said Smeeton, a postdoctoral fellow in the laboratory of Gage Crump and this year’s Broad Fellow, the third since 2014. “Currently, there really isn’t that much we can do for the cartilage in these smaller joints, other than treat the symptoms with steroids or painkillers.”

As part of the quest for new and better treatments, her Broad Fellowship project leverages a key discovery that she and her colleagues recently published in the journal eLife. They found that certain joints in zebrafish jaws and fins have features similar to the type of mammalian joint susceptible to arthritis.

By damaging a ligament that stabilizes the adult zebrafish jaw, she can reliably induce cartilage damage and arthritis. Just as reliably, the zebrafish can repair the damage. Smeeton aims to understand which progenitor cells are regenerating the ligament and cartilage in the zebrafish jaws, and why similar repair fails to occur in humans.

In the future, these findings may help in devising strategies to stimulate analogous progenitor cells in patients’ joints toward boosting cartilage and ligament regeneration, she said.