By: Richard Huang
Scientists in Israel have artificially created and grew a synthetic mouse embryo that has three functioning vital organs, bringing a potential of human organ replacement.
The synthetic embryo derived from an agglomeration of embryonic stem cells that is extremely similar to the real mouse embryo, with rudimentary beating hearts, blood circulation, folded brain tissue and intestinal tracts. The man-made embryo ceased to grow after developing for eight days, about a third of a real mouse pregnancy.
By taking a peek at the earliest stage of embryo development, scientists can observe closely the formation of organs, which may indirectly provide some solutions to the current incurable diseases. According to the scientists involved with the research, their objective of this experiment is not just successfully growing an artificial mouse without real embryos, but also using the observations to find new ways that can possibly cure human organs.
“Our goal is not making pregnancy outside the uterus, whether it’s mice or any species,” said Jacob Hanna, the stem cell scientist at the Weizmann Institute of Science. “We are really facing difficulties making organs — and in order to make stem cells become organs, we need to learn how the embryo does that. We started with this because the uterus is a black box — it is not transparent.”
Although the research successfully proves that a complete mouse embryo can be created from embryonic stem cells, only a small number of embryos developed a beating heart and other organs in early stages. Additionally, the close resemblance between the artificial embryo and the actual embryo does not mean they are exactly the same thing, and it did not produce real, artificial mice from the womb, said Hanna.
“It’s an interesting next step, not shocking, but one that makes more plausible in the long run a proposition with broad implications: the possibility of turning any mouse cell into a living mouse,” said Henry T. Greely, a bioethicist at Stanford Law School.
After this research and other recent studies, several researchers have agreed that synthesizing a complete human embryo can be possible in the future. However, human embryos are strictly prohibited from being implanted into a uterus.
“The mouse is a starting point for thinking about how one wants to approach this in humans,” said Alex Meissner, a stem cell biologist at Max Planck Institute for Molecular Genetics. “It’s not necessary to be alarmed or raise any panic, but … as we learn, it’s important to have in parallel the discussion: How far do we want to take it?”