Synthetic mouse embryos were created without using a sperm or egg; then, for the next eight days, the embryos were grown in an artificial womb by stem-cell researchers in Israel. This experiment opened doors of possibilities for science, giving hope that one day it may be possible to create replacement organs for humans.
Scientists clarified that their objective wasn’t to learn how to reproduce outside the womb, but to use the knowledge of how organs develop in embryos to help heal people more efficiently.
According to The Washington Post, “From a clump of embryonic stem cells, scientists at the Weizmann Institute of Science created synthetic embryos that closely resembled real mouse embryos, with rudimentary beating hearts, blood circulation, folded brain tissue and intestinal tracts. The mouse embryos grew in an artificial womb and stopped developing after eight days, about a third of a mouse pregnancy.”
Scientists have been making a huge effort to create embryo models from both human and mouse cells. These models can help researchers understand “the earliest stages of embryonic development and how organs form.”
“This is an important landmark in our understanding of how embryos build themselves,” said Alfonso Martinez Arias, a development biologist at Pompeu Fabra University in Barcelona, in an email, calling the findings a “game changer.”
Published on Monday, August 1st, in the journal Cell, the research shows that even growing a mouse, much less a human, outside the womb would be highly difficult and scientists are still far from figuring that out. “It was proof of concept that a complete synthetic embryo could be assembled from embryonic stem cells, and while the researchers were successful, it was a highly error-prone process, with only a small fraction of embryos going on to develop the beginnings of a beating heart and other organs,” wrote Carolyn Y. Johnson in an article for The Washington Post.
Jacob Hanna, a stem-cell scientist at the Weizmann Institute of Science who led the experiment said that despite the close similarities between the synthetic mouse embryos and natural mouse embryos, they weren’t exactly the same and didn’t cause any real pregnancies in real mice.
Henry T. Greedy, a bioethicist at Stanford Law School, described the research as interesting, but not shocking. The possibility of creating a live mouse with any mouse cell was perhaps the easiest step forward in the journey to find new ways to heal humans.
Similar to other recent studies, the findings put a complete human synthetic embryo into the picture, making it necessary to have a societal discussion about how this new information should be handled. Last year, the International Society for Stem Cell Research made the “14-day rule,” a rule that allowed researchers to grow natural embryos for only 14 days in the laboratory, more flexible, allowing researchers to extend their studies.
“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?”
Hanna explained his desire to develop the technology into something that could be studied and used therapeutically for humans, not as an alternative for reproduction.
“Our goal is not making pregnancy outside the uterus, whether it’s mice or any species,” Hanna said. “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.”
Sources: https://www.washingtonpost.com/science/2022/08/01/synthetic-mouse-embryo/
Scientists clarified that their objective wasn’t to learn how to reproduce outside the womb, but to use the knowledge of how organs develop in embryos to help heal people more efficiently.
According to The Washington Post, “From a clump of embryonic stem cells, scientists at the Weizmann Institute of Science created synthetic embryos that closely resembled real mouse embryos, with rudimentary beating hearts, blood circulation, folded brain tissue and intestinal tracts. The mouse embryos grew in an artificial womb and stopped developing after eight days, about a third of a mouse pregnancy.”
Scientists have been making a huge effort to create embryo models from both human and mouse cells. These models can help researchers understand “the earliest stages of embryonic development and how organs form.”
“This is an important landmark in our understanding of how embryos build themselves,” said Alfonso Martinez Arias, a development biologist at Pompeu Fabra University in Barcelona, in an email, calling the findings a “game changer.”
Published on Monday, August 1st, in the journal Cell, the research shows that even growing a mouse, much less a human, outside the womb would be highly difficult and scientists are still far from figuring that out. “It was proof of concept that a complete synthetic embryo could be assembled from embryonic stem cells, and while the researchers were successful, it was a highly error-prone process, with only a small fraction of embryos going on to develop the beginnings of a beating heart and other organs,” wrote Carolyn Y. Johnson in an article for The Washington Post.
Jacob Hanna, a stem-cell scientist at the Weizmann Institute of Science who led the experiment said that despite the close similarities between the synthetic mouse embryos and natural mouse embryos, they weren’t exactly the same and didn’t cause any real pregnancies in real mice.
Henry T. Greedy, a bioethicist at Stanford Law School, described the research as interesting, but not shocking. The possibility of creating a live mouse with any mouse cell was perhaps the easiest step forward in the journey to find new ways to heal humans.
Similar to other recent studies, the findings put a complete human synthetic embryo into the picture, making it necessary to have a societal discussion about how this new information should be handled. Last year, the International Society for Stem Cell Research made the “14-day rule,” a rule that allowed researchers to grow natural embryos for only 14 days in the laboratory, more flexible, allowing researchers to extend their studies.
“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?”
Hanna explained his desire to develop the technology into something that could be studied and used therapeutically for humans, not as an alternative for reproduction.
“Our goal is not making pregnancy outside the uterus, whether it’s mice or any species,” Hanna said. “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.”
Sources: https://www.washingtonpost.com/science/2022/08/01/synthetic-mouse-embryo/
