Heartbeat aids blood stem cell formation in embryos

The two study groups and their findings
The research was carried out by two groups. The first group was led by Leonard Zon and his colleagues from the Oncology division at Children's Hospital Boston.

The second group comprised of George Daley, director of the Stem Cell Transplantation Program at Children's Hospital Boston, and the director of Brigham and Women's Hospital and scientists from the Indiana University School of Medicine.

Zebrafish was used to carry out the research as it has a transparent embryo, allowing undeviating surveillance of the developing embryo.

The first team revealed that blood flow altering compounds had a strong impact on Runx1, which is the controller of blood formation and is also a standard indicator for the blood cells that help in the growth of cell types in the blood system.

They also observed that increased production of nitric oxide aided production of blood cells in the transformed fish embryos, while decreased production of nitric oxide reduced the number of blood cells.

“Nitric oxide appears to be a critical signal to start the process of blood stem cell production. This finding connects the change in blood flow with the production of new blood cells,” says Leonard Zon.

The second group examined mechanical stimulation’s effect on blood formation in the embryo of mice. They observed that the fluid flow on the surface of cells augments the Runx1 and genetic markers found in blood stem cells.

What the findings mean
The results make it clear that bio-mechanical forces play an important part in blood formation. They may also provide an answer for embryos’ heart beat that begins before blood is infused in the tissues.

Researchers anticipate that these new findings on blood formation could help in the treatment of blood-related diseases like leukemia, immune insufficiency and sickle cell anemia.

The studies have been published in the online edition of journals ‘Cell’ and ‘Nature’ respectively.