Twenty years ago, Dr. Alan Tyndall, a rheumatologist at University Hospital in Basel, Switzerland, was faced with giving a 37-year-old mother a grim diagnosis.

Scleroderma, the autoimmune disease that pumps excess collagen into the body, was turning her pulmonary arteries into stone.

The disease would be fatal. Even a lung transplant couldn’t save her.

So Tyndall and his colleagues, including hematologist Dr. Alois Gratwohl, came up with a bold plan.