Stem cell scientists based at Monash University have made an exciting discovery that may bring them one step closer to the development of a treatment for a variety of blood disorders and diseases. Reporting their findings in the journal Nature, the researchers reveal some of the key steps involved in the generation of blood stem cells in the body, a process which was previously poorly understood.

Hematopoietic stem cells (HSCs) are self-renewing cells found in the bone marrow that can give rise to every type of blood cell in the body. Researchers have been aware of their usefulness in medicine for many years and consequently they’re used to treat a variety of ailments including some blood disorders and cancers such as leukemia.

Scientists believe that the uses of these cells could potentially extend far beyond the replacement of blood or immune cells, but so far they have been faced with significant hurdles. One particular challenge has been a lack of understanding of the triggers that lead to the generation of these cells, which has meant that scientists have been unable to produce them in the lab. According to lead researcher of the recent study Professor Peter Currie, understanding how these cells self-renew to replenish blood is a “Holy Grail” of stem cell research. Now, the researchers believe they may have unveiled some of the critical steps that lead to their formation.

For the present investigation, Monash researchers examined the zebrafish- a model animal that is useful for the study of vertebrate development because the embryos are transparent, develop rapidly and are simple in terms of organization.

The scientists were interested in divulging the signals that lead to the production of HSCs, so they adopted high-resolution microscopy to image how these cells form in the developing embryo.

They found that HSC formation was induced by a specific population of cells found in a sub-compartment of the developing zebrafish called an endotome. These endotomal cells eventually give rise to endothelial cells which form the linings of blood vessels.  

“Endotome cells act like a comfy sofa for pre-HSCs to snuggle into, helping them progress to become fully fledged stem cells,” Currie said in a news-release. “Not only did we identify some of the cells and signals required for HSC formation, we also pinpointed the genes required for endotome formation in the first place.”

Currie explains that if they can eventually discover the endotome signals that result in embryonic HSC generation, then they may be able to use them in the lab to produce different blood cells for the treatment of various blood disorders. Potentially, he says, they may even one day be able to correct genetic defects and then transplant the cells back into the patient, which is exciting.

While the researchers are not equipped with enough information to be able to produce the cells on demand for patients just yet, their findings certainly serve as a platform for future research which could yield further vital information.