The National Heart, Lung, and Blood Institute (NHLBI), part of the National Institutes of Health, awarded two research grants to The Children’s Hospital of Philadelphia (CHOP). The funding will support two research programs to engineer human stem cells into a new generation of cells and tissues for patients with blood diseases, cancer and other disorders. Stem cells are nonspecific cells that can renew themselves for prolonged periods. They can also develop into different cell types, making them a potentially renewable source of replacement cells that could be used in the future to treat many conditions.

The first program, “Embryonic Stem Cell-Derived Platelets as Cellular Therapeutics,” is funded by a seven-year, $16.8 million grant. NHLBI issued the grant under a new initiative called the NHLBI Progenitor Cell Biology Consortium. Mortimer Poncz, MD, chief of hematology at CHOP is co-principal investigator of the program. The grant was awarded jointly to CHOP and Fred Hutchinson Cancer Research Center/University of Washington Cancer Consortium. Poncz and his team will develop human embryonic stem cells (hESCs) to improve platelet supplies for hematology and oncology patients, as well as use platelets to deliver customized proteins to injured blood vessels. hESCs are derived from human embryos fertilized in vitro fertilization clinics and donated for research. They have drawn great interest from the research community for their capacity to develop into every type of tissue in the body.

Researchers will also be working to modify platelets and use them as therapy-delivery vehicles to treat conditions such as bleeding disorders. In previous studies using mice with hemophilia, Poncz and his team treated the disorder by augmenting platelets with the deficient clotting factor. “In addition to investigating platelets for treating hemophilia in people, we will investigate their potential role in delivering other bioactive proteins to sites of vascular injury,” said Poncz. “For instance, platelets might deliver an enzyme called urokinase to selectively disintegrate blood clots.” Such a therapy could be particularly helpful for individuals susceptible to excessive and potentially harmful clots.

The second program, funded through a separate two-year NHLBI grant totaling $997,000, is headed by Mitchell Weiss, MD, PhD, hematologist at CHOP and Associate Professor of Pediatrics at the University of Pennsylvania. The grant, funded by the American Recovery and Reinvestment Act, is part of an NHLBI program to support novel research designed to quickly advance an area of biomedicine in significant ways. It will focus on generating induced pluripotent stem cells (iPSCs) to enhance understanding of several types of diseases, to create healthy replacement tissues for sick patients.

“These two grants illustrate the promising future that stem cell biology holds, not only for research purposes and for hematologic and oncologic disorders, but for a wide range of diseases that presently have suboptimal therapies. The future of stem cell therapy may be limited only by our imagination,” added Poncz.

Source: Medical News Today, February 16, 2010