Professor Donald Metcalf, who has died aged 85, was a leading cell biologist who spent more than 40 years trying to find a hormone many thought did not exist; his eventual discovery of colony stimulating factors (CSFs), substances which control how white blood cells form and resist infections, radically changed cancer treatments, helping to save the lives of millions of people.
When Metcalf began his research at the Walter and Eliza Hall Institute of Medical Research in Melbourne, Australia, in 1964, he told the director he wanted to find a cure for leukaemia. “He said to me: 'Death from cancer is inevitable. There is no cure for it, and anyone that does research on it is a crook’,” Metcalf recalled.
CSFs had first been postulated in 1906 by French scientists who described what they believed to be a hormonal role in the formation of blood cells. But it was not until the 1960s, when Metcalf developed techniques to culture blood cells, that it was possible to prove their existence.
Metcalf knew that white blood cells become severely depleted in patients undergoing chemotherapy, leaving them vulnerable to infections, but he speculated that there must be a hormone, or hormones, that control white blood cell production that could be harnessed to give cancer patients a better chance of survival.
In 1977, he isolated such a hormone in a mouse and over the next few years he and colleagues identified and purified four hormones that regulate blood cell production. These were dubbed “colony stimulating factors”, or CSFs, because they stimulated the production of white blood cells. With CSFs boosting their immune system, he reasoned, cancer patients could receive higher doses of chemotherapy.
By the late 1980s advances in genetic techniques enabled the mass production of CSFs, and they were rolled out to clinics around the world. As well as benefiting cancer patients CSFs have also revolutionised transplant medicine, leading to new techniques for performing bone marrow transplants on patients with blood diseases such as leukaemia .
An early beneficiary was the Spanish tenor José Carreras, who developed acute myeloid leukaemia in 1987 and had been given a bone-marrow transplant that failed to arrest the disease. With death a strong possibility, he accepted the offer of CSF treatment in association with high-dose chemotherapy. Within 24 hours he showed a positive response and eventually recovered.
An estimated 20 million people have now been treated with CSFs.
Donald Metcalf was born on February 26 1929 and studied Medicine at the University of Sydney. After graduation he joined Professor Sir Frank Macfarlane Burnet’s laboratory at the Walter and Eliza Hall Institute, where he cut his teeth studying vaccinia virus before embarking on his research into leukaemia. In 1966 he became deputy director of the institute under its newly-appointed director Sir Gustav Nossal.
Metcalf continued to work even after being diagnosed with metastatic pancreatic cancer, for which he himself underwent chemotherapy. He received more than 40 awards including the Lasker Award, the Royal Medal of the Royal Society , and the Prime Minister’s Prize for Science in Australia. He was appointed a Companion of the Order of Australia in 1993. His autobiography, Summon up the Blood, was published in 2000.
Metcalf is survived by his wife, Jo, and by their four daughters.
Professor Donald Metcalf, born February 26 1929, died December 15 2014 
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