vendredi 23 octobre 2015

Killed In A Bike Crash, Scientist’s Thyroid Stem Cell Work Lives On

Killed In A Bike Crash, Scientist’s Thyroid Stem Cell Work Lives On

Anita Kurmann's ghost bike is fastened to a street sign at the Back Bay intersection where she died. (Hadley Green for WBUR)

Anita Kurmann’s ghost bike is fastened to a street sign at the Back Bay intersection where she died. (Hadley Green for WBUR)

On Aug. 7, a flatbed truck struck and killed Dr. Anita Kurmann, a Swiss surgeon and scientist, as she rode her bicycle in Boston’s Back Bay. She was 38, and just on the verge of launching her own lab.

Her death has brought an outpouring of grief in recent weeks — from family in Switzerland, from her admiring colleagues at Boston hospitals, from the city’s cycling community.

This week brings Kurmann’s scientific memorial: A paper by a team of 17 researchers in the journal Cell Stem Cell, reporting a major advance on using stem cells to grow thyroids.

Dr. Anita Kurmann, who was killed in a bike accident in August. (Courtesy BIDMC)

Dr. Anita Kurmann, who was killed in a bike accident in August. (Courtesy Boston University)

Kurmann had found out just days before she died that the paper was likely to be accepted for publication, and her colleagues dedicated it to her memory. The dedication reads in part: “She was intelligent, well read, kind, humble, and tirelessly committed to her patients, her thyroid research, her family, and her colleagues, who miss her dearly.”

The paper describes, in effect, nature’s recipe for growing a thyroid, the butterfly-shaped gland in your neck that can speed up or slow down your bodily functions.

“She was incredibly proud of this work,” says Dr. Anthony Hollenberg of Beth Israel Deaconess Medical Center. “She was able to figure out how to do the mouse surgical experiments that were required to see that the stem cells functioned.”

Dr. Darrell Kotton, of Boston Medical Center’s and Boston University’s Center for Regenerative Medicine, who oversaw the research with Hollenberg, says Kurmann’s loss remains difficult to accept on many levels.

“I’m not only speaking about the grief one feels when suddenly losing someone close to you,” he said, “but in Anita’s case, one can’t help but feel the loss of so much potential, and the loss of all the scientific progress she was about to contribute to the world.”

Kurmann had a faculty position waiting for her and planned to return home to Switzerland and launch her own lab at the end of the year, he said. “So the world really has lost a unique person who was about to lead a team that was to propel her discoveries forward using everything she had learned and developed.”

“It’s hard to believe she’s gone.” he added, “and I just still often imagine her returning home as a scientist-surgeon treating her patients but also teaching her own trainees how to grow and transplant these special thyroid progenitor cells she was able to engineer from pluripotent stem cells.”

To translate: Kurmann and her co-first author, Boston University’s Maria Serra, were experimenting on stem cells at the “pluripotent” stage, when they could grow into multiple types of cells. The paper identifies key factors that appear to tip the cells into “deciding” to become thyroid cells, and the team showed that they could coax human stem cells into becoming functional, hormone-emitting thyroid tissue.

The work is basic research that casts more light on how early stem cells decide whether to become, say, a lung or a thyroid. But Hollenberg says it could help patients someday, too: The idea would be to take a patient’s own cells and get them to grow into thyroid cells for people who lack a functioning thyroid.

“That’s obviously far in the future, but we’re on our way,” he said.

So might it help the millions of Americans with under-active thyroids?

There’s an additional barrier to helping most hypothyroid patients, said Hollenberg, who is chief of Endocrinology, Diabetes and Metabolism at Beth Israel Deaconess Medical Center. If you lose your thyroid to Hashimoto’s disease, the most common cause of hypothyroidism, the cause is your own immune system’s attack on the thyroid.

“So the problem is, if I took your stem cells, turned them into thyroid cells, and transplanted them back into you, your immune system would again attack them,” he said. Stem cell work on Type 1 Diabetes faces a similar challenge: Researchers need to both make insulin-producing cells and to somehow stop the immune system from attacking them, he noted.

That extra barrier is why the team sees more promise in using stem cells to to help patients who have lost their thyroids or have been born without thyroids for reasons unrelated to immune-system attacks, he said.

Kotton said he hopes the team can find ways to continue the work that Kurmann began, in her honor. “I really do believe it’s what she would have wanted,” he said.

The Boston Police Department says the crash that killed Kurmann is still under investigation. The city, which had already identified the intersection where Kurmann died as dangerous, has made several changes there, including to the traffic signals and road markings. But experts say there are many other similarly perilous intersections around the city.

At the intersection of Beacon Street and Massachusetts Avenue, where Kurmann died, her fellow cyclists have installed a white “ghost bike,” a cyclist ritual, to mark the spot and remind drivers of potential danger.

(Carey Goldberg/WBUR)

(Carey Goldberg/WBUR)

Special thanks to multimedia journalist Hadley Green for photos and audio.

Aucun commentaire:

Enregistrer un commentaire