Amy Wagers's research discoveries have landed her in the middle of some hotly contested questions about the capabilities of adult versus embryonic stem cells.
Wagers studies blood-forming and muscle-forming stem cells in her laboratory at the Joslin Diabetes Center at Harvard Medical School, with an eye toward treating diseases such as cancer, anemia, muscular dystrophy, and diabetes. Her research suggests that defects in aging stem cells may be reversible, and her studies in mice support the feasibility of stem cell therapy for treating degenerative muscle disease.
Although she was always interested in biology, a single phone call set Wagers on the path to studying stem cells. As an undergraduate, she signed up to donate bone marrow. A few years later, in graduate school, she learned she was a match for a person who needed a transplant. She devoured reading materials describing the procedure, eager to learn about how her cells could help. In the end, her marrow wasn't needed, but what she'd learned convinced her to become a stem cell biologist. "I saw the power of these cells for treating disease," Wagers says. She sought out a postdoctoral fellowship focused on stem cells.
"I remember seeing Irv Weissman in the news," Wagers recalls. It was the late 1990s, and Weissman, a prominent stem cell biologist at Stanford University, had discovered blood-forming (hematopoietic) stem cells in mice. She applied to four stem cell labs for postdoctoral work, including Weissman's, and joined his lab in 1999.
Researchers had found some evidence from animal studies suggesting that hematopoietic stem cells—which are adult stem cells—are pluripotent and therefore able to divide to create many different types of cells, including heart muscle cells and neurons. Did this mean that embryonic stem cells, which are derived from embryos to generate many types of cells, were no longer needed for research? Those who felt strongly that embryonic stem cells should not be used for research argued yes.
Wagers designed an experiment to clearly answer the question. She knocked out a mouse's blood stem cells altogether and then introduced a single blood-forming stem cell into the animal. She showed that this single blood stem cell could fully reconstitute the blood system, but did not generate other types of cells. She also specifically showed that blood-forming stem cells could not repair damaged heart muscle or form female egg cells. This young researcher's findings refuted claims that adult stem cells were pluripotent and settled a vigorous scientific debate.
More recently, Wagers discovered a way to identify and collect adult muscle stem cells. She transferred some of those cells from healthy mice into mice with a disease similar to Duchenne muscular dystrophy. The cells healed the diseased muscle, and they replicated to form a pool of healthy stem cells that could respond to future injury.
"There's a lot to discover and many open questions that touch on so many aspects of biology," Wagers says, explaining why she finds stem cell biology so exciting. "The field is moving rapidly. Every time I go to a meeting, there's always something that amazes me."
Wagers credits her research mentors for helping her gain personal and professional confidence. "They gave me the opportunity to do things I didn't think I could do," she says. And when things didn't work out, perseverance helped her through. "Failure can be good," she says. "And fear of failure can be extremely motivating. I never want to be in a position where I'm sure I'll succeed."
Outside the lab, Wagers likes to test her limits and seek out excitement, most recently with trapeze lessons. "The trapeze is all about timing and belief and trust," she says. "And the thrill of climbing up a couple of stories and then jumping."
Sometimes a couple of stories isn't enough. When an important paper is published, Wagers celebrates by going skydiving.