Several teams of scientists say they have isolated the substance the body uses to make blood platelets, which are needed to make the blood clot.
Their findings, published in the science journal Nature, could help cancer patients whose blood does not clot properly.The scientists, working at the University of Washington School of Medicine, the Mayo Clinic, Genentech and ZymoGenetics Corporation in the United States, as well as at Inserm in Villejuif, France, found the hormone thrombopoietin could be isolated and purified.
Donald Metcalf of the Royal Melbourne Hospital said their findings were a breakthrough.
"The impressive feature of thrombopoietin is its apparent ability to increase platelet numbers to previously unattainable levels, and the prospects look good that it will quickly find wide clinical applications," Metcalf wrote in an accompanying commentary to the four articles.
Patients with too few platelets risk hemorrhage. Those undergoing chemotherapy or who have had bone marrow transplants have low levels and they only slowly get back to normal.
Doctors have been looking for a substance that could be used to stimulate platelet production. Metcalf said the findings gave researchers plenty of material to work with.
"A busy time lies ahead for biologists and clinicians," he wrote.
"But expectations do need to be realistic. A regulator needs target cells to elicit a response, and the badly damaged marrow of a patient after intensive chemotherapy may well no longer contain enough targets to allow maximum possible platelet responses."