By Elaine Schattner, MD|January 11th, 2011
There’s hematology news today, x 2 (at least):
1. Progress in developing synthetic red blood cells –
A University of North Carolina, Chapel Hill-based research group has created hydrogel particles that mimic the size, shape and flexibility of red blood cells (RBCs). The researchers used PRINT® (Particle Replication in Non-wetting Templates) technology to generate the fake RBCs, which are said to have a relatively long half-life. The findings were reported on-line yesterday in PNAS (abstract available, subscription required for full text). According to a PR-ish but interesting post on Futurity, a website put forth by a consortium of major research universities, tests of the particles’ ability to perform functions such as transporting oxygen or carrying therapeutic drugs have not yet been conducted.
Developing competent, artificial RBCs is a hematologist’s holy grail of sorts, because with that you might alleviate anemia without the risks of transfusion.
2. Progress in using human stem cells to generate lots of platelets –
In an exciting paper published today in Cell Research, investigators stimulated human embryonic stem cells to become platelet-producing cells, called megakaryocytes. According to the article (open-text at Nature PG), the platelets were produced in abundance, appeared typical and clotted appropriately in response to stimuli in vitro. The researchers injected them into mice, used high-speed video microscopy for imaging, and demonstrated that the stem cell-derived human platelets contributed to clot formation in mice, in vivo (i.e., they seem to work).
The research team includes scientists at Harvard Medical School, the University of Illinois and Cha University in Seoul. Several authors are affiliated with either or both of two biotech companies: Stem Cell and Regenerative Medicine International (address in Marlborough, MA) and Advanced Cell Technology (headquarters in Santa Monica, CA; lab in Marlborough, MA).
Platelets are tiny blood cells essential in wound repair and clotting upon injury. For some patients with bone marrow disorders, such as leukemia, or chemotherapy-induced thrombocytopenia (low platelets) with bleeding, there’s a significant transfusion demand for this blood component. If safe, functional human platelets could be manufactured from self-replicating stem cells in a lab, that would significantly reduce the need for platelets in the blood supply.