CSIRO scientists have developed a new way to harvest stem cells, which is less invasive and reduces side effects for donors.

For bone marrow transplantation, stem cells are usually harvested from healthy donors to treat patients with cancers including leukaemia.

But harvesting this way takes a long time and requires injections of a growth factor to boost stem cell numbers, and can come with serious side effects.

The new technique reduces the time required to obtain adequate numbers of stem cells, without the need for a growth factor.

The method was developed by a team of CSIRO researchers working within the manufacturing arm of CSIRO and with the Australian Regenerative Medicine Institute (ARMI) at Monash University.

It combines a newly discovered molecule (known as BOP), with an existing type of molecule (AMD3100) to mobilise the stem cells found in bone marrow out into the blood stream.

CSIRO researcher Dr Susie Nilsson said her team was able to demonstrate that combining the two molecules directly impacts stem cells so they can be seen in the blood stream within an hour of a single dosage.

“Current treatment requires the patient to have growth factor injections for several days leading up to the procedure,” Dr Nilsson said.

“Using the new method eliminates the need for this, meaning a procedure that once took days can be reduced to around an hour.”

Until now AMD3100 has only been effective in increasing stem cell numbers when combined with the growth factor.

“But the growth factor can cause unpleasant side effects like bone pain and spleen enlargement for some patients,” Dr Nilsson said.

“Other patients simply don’t respond well, and their stem cell count never gets high enough for a successful transplant.”

The scientists found that combining the two small molecules not only eliminates the need for the growth factor, but when the harvested cells are transplanted they can replenish the entire bone marrow system, and there are no known side effects.

There has been some success already in pre-clinical studies, and a phase 1 clinical trial assessing the combination of BOP molecule with the growth factor is planned.