Researchers in Australia use zebrafish to make stem cell breakthrough
Discovery could lead to better treatment for blood-related diseases such as leukaemia
Australian researchers studying zebrafish have made one of the most significant ever discoveries in stem cell research.
They have uncovered the mystery of how a critical type of stem cell found in blood and bone marrow, and essential to replenishing the body's supply of blood and immune cells, is formed.
The cells, called hematopoietic stem cells (HSC), are already used in transplants for patients with blood cancers such as leukaemia and myeloma.
But HSCs have significant potential to treat a broader range of conditions because they appear to be able to form all kinds of vital cells including muscle, blood vessel and bone.
The problem was scientists had no idea how HSCs formed, making growing them in a lab and using them to treat spinal cord injuries, diabetes and degenerative disorders impossible.
However, a research team led by Professor Peter Currie, from the Australian Regenerative Medicine Institute at Victoria's Monash University, uncovered a major part of HSC's development. Understanding how HSCs self-renew to replenish blood cells is considered the holy grail of advancing stem cell research.
Using high-resolution microscopy, Currie's team filmed HSCs as they formed inside zebrafish embryos. In playing the film back, they noted that a "buddy" cell appeared to help HSCs form.
"It's a sad fact of life that humans are basically just modified fish, and our genomes are virtually identical to theirs," Currie said.
The researchers were initially studying muscle mutations in the zebrafish. But in playing the film back they noticed that the muscle-deficient zebrafish had several times the normal population of HSCs.
They saw the pre-HSCs required a "buddy" cell, known as endotome cells, to turn into HSCs.
Currie said researchers could now focus on finding the signals present in the endotome cells responsible for HSC formation in the embryo.
"Then we can use them in the lab to make different blood cells on demand for all sorts of blood-related disorders," he said.
If they could do this, there would also be the potential for genetic defects in cells to be corrected, he said.