Team turns stem cells into a fish embryo

The brain of the vertebrate embryo built in vitro. (Credit: U. Virginia)

By turning embryonic stem cells into a fish embryo, researchers have taken a major step toward growing whole organs and tissues from stem cells.

“We have generated an animal by just instructing embryonic cells the right way,” says Chris Thisse of the department of biology at the University of Virginia.

“If we know how to instruct embryonic cells, we can pretty much do what we want,” she says. For example, scientists will be able one day to instruct stem cells to grow into organs needed for transplant.

Researchers were able to identify the signals sufficient for starting the cascade of molecular and cellular processes that lead to a fully developed fish embryo. With this study came an answer to the longstanding question of how few signals can initiate the processes of development: amazingly, only two.

‘He has everything’


Published in the journal Science, the study sheds light on the important roles these two signals play for the formation of organs and full development of a zebrafish embryo. Moreover, it is now possible to direct embryonic development and formation of tissues and organs by controlling signal locations and concentrations.

The generated embryo was smaller than a normal embryo, because the researchers instructed a small pool of embryonic stem cells, but “otherwise he has everything” in terms of appropriate development, says Bernard Thisse of the cell biology department.

The next step will be to try and reproduce the findings using mice. Researchers expect molecular and cellular mechanisms will be extremely similar in mice and other mammals, including humans.

Source: University of Virginia