These findings could have huge implications for modeling diseases in embryos and placentas, and pave the way for creating whole embryos from skin cells in humans.
What have they managed to do?
The research team successfully created the three major stem cell types in embryo form from skin cells using mouse cells. The research could conceivably be replicated using human skin cells in the near future.
The study was published in the journal Cell Stem Cell, and the team, led by Yossi Buganim of HU's Department of Developmental Biology and Cancer Research, managed to find a set of genes that can trigger the change in skin cells.
Using these gene sets, the team were able to transform murine (rats and mice) skin cells into the three major cell types of an early embryo. These are, for reference:
- The cells of the embryo itself;
- The cells of the placenta, and;
- Cells that constitute extra-embryonic tissue (like the umbilical cord).
The team believes it may be possible to adapt the technique to create human embryos in the future without the need for human gametes.
"This discovery also has vast implications for modeling embryonic defects and shedding light on placental dysfunctions, as well as solving certain infertility problems by creating human embryos in a petri dish," notes Science Daily.
How did they do it?
As interesting as their findings are, this is not the first time a similar study has been conducted.
Back in 2006, Japanese researchers managed to discover that skin cells can be "reprogrammed" into early embryonic cells that led to a viable fetus by using embryonic genes.
Termed "Induced Pluripotent Stem Cells" (iPSCs), these are similar to cells that develop in the early days of natural fertilization.
However, there was a clear difference in the new study. Extra-embryonic tissues and placental cells were not replicated using this earlier technique.
The HU team managed to find a new combination of five genes that, when inserted into skin cells, reprogram the cells in a similar fashion. But, the key difference being, that each of three early embryonic cell types was expressed, not just those that make up the embryo.
The process, according to their study, took around a month to complete.
They selectively introduced different genes (like "EOMES" or "ESRRB") into skin cells and watched how the skin cell changed over time. The team found that during the first stage, skin cells lose their cellular identity and slowly change into a new form under the introduced genes influence.
Eventually, each one acquired a new identity of one of the three early embryonic cell types depending on which gene was introduced.
The potential impact of the study
To date, other studies have been conducted to attempt to develop an entire mouse embryo without using sperm or egg cells. All of these used isolated early cell types from live developing embryos.
"However, HU's study is the first attempt to create all three main cell lineages at once from skin cells. Further, these findings mean there may be no need to 'sacrifice' a live embryo to create a test tube embryo," declares Science Daily.
The original study was published in the journal Cell Stem Cell.