Boston Scientists Created Human Platelets With a ‘Next-Generation Bioreactor’

According to Brigham and Women’s Hospital (BWH) researchers, every year in the U.S., more than 2.17 million platelet units (blood cells that form clots) are transfused to patients. But an increase in demand, a short five-day shelf-life, and the possibilities of contamination, rejection, and infection have made blood platelet shortages common.

But a new finding by BWH researchers may have just changed the way transfusions are performed forever. Scientists developed a “platelet bioreactor” that can generate fully functional human platelets in vitro. This biomedical advancement, researchers say, could help to address blood transfusion needs worldwide.

The study is published July 21, 2014 in Blood.

“The ability to generate an alternative source of functional human platelets with virtually no disease transmission represents a paradigm shift in how we collect platelets that may allow us meet the growing need for blood transfusions,” said Jonathan Thon, the study’s lead author, and a researcher in the Hematology Division at BWH.

In the study, the researchers say that the bioreactor “combines the major components of bone marrow and models its composition and blood flow characteristics.”

This is how the bioreactor works, according to BWH:

Blood cells, such as platelets, are made in bone marrow. The bioreactor—a device that mimics a biological environment to carry out a reaction on an industrial scale—uses biologically inspired engineering to fully integrate the major components of bone marrow, modeling both its composition and blood flow characteristics. The microfluidic platelet bioreactor recapitulates features such as bone marrow stiffness, extracellular matrix composition, micro-channel size, and blood flow stability under high-resolution live-cell microscopy to make human platelets.

Application of shear forces of blood flow in the bioreactor triggered a dramatic increase in platelet initiation from 10 percent to 90 percent, leading to functional human platelets.

“The regulatory bar is appropriately set high for blood products, and it is important to us that we show platelet quality, function, and safety over these next three years since we’ll likely be recipients of these platelets ourselves at some point,” Thon said.

When the three years is up, in 2017, researchers hope to begin human clinical trials. In the report, the researchers wrote that that their findings could help meet increasing global demand for donor blood.

“Bioreactor-derived platelets theoretically have several advantages over conventional, donor-derived platelets in terms of safety and resource utilization,” said William Savage, MD, medical director of the Kraft Family Blood Donor Center at Dana Farber Cancer Institute/Brigham and Women’s Hospital, who did not contribute to the study. “A major factor that has limited our ability to compare bioreactor platelets to donor platelets is the inefficiency of growing platelets, a problem that slows progress of clinical research. This study addresses that gap, while contributing to our understanding of platelet biology at the same time.”