Equipment for incubating thousands of human embryos at the same time and the future of 'synthesizer' from just one stem cell?

In a new study published in the journal Nature, the scientists describe a newly invented breakthrough device. It is a microfluidic channel that allows the simultaneous creation of countless living organisms that resemble human embryos at an early stage.

This is thought to be an important step forward in the field of human embryonic development research. But it also raises a question: Does this device " draw a path for deer to run ", resulting in the incubation of " synthetic " mass embryos?

This device allows the simultaneous creation of countless living organisms that resemble human embryos at an early stage.

A " nursery " produces thousands of human embryos at once

In the past, many scientists have also successfully created synthetic embryos, also known as "embryoids". These entities are created by orienting human stem cells, developing into structures found in human embryos at an early stage.

These structures include epiblats, a group of original stem cells clumped together, initiating the formation of the fetus; It will then develop into amniotic sac and two post-epiblats cell arrays, one developing fetal component including head and torso, one developing fetal posterior component including two lower limbs.

The more they study, the more scientists want to create the most complete embryos. But sometimes they wonder if they should do it or not?

Now, new research in the journal Nature has taken a step that allows scientists to create human embryos at a very early stage, not just one by one but a series of embryos in a short time.

" This new system allows us to achieve outstanding efficiency to create human-like structures , " said Jianping Fu, associate professor of biomedical engineering at the University of Michigan in Ann Arbor.

Each of these devices can produce about a dozen workpieces in just a few days.

The device he and his colleagues created was a thin square shape and made of silicon. Each plate contains four wells developed around a narrow channel. Scientists just need to put the cells they want to grow into, it can be human embryonic stem cells, pluripotent stem cells or any type of stem cells that can be reprogrammed from cells. mature.

Next, the researchers added chemicals in adjacent wells to stimulate cells to grow into the main structures of human embryos. In another well, there is already a gel that mimics the wall of the uterus.

Fu said the current embryo culture equipment has a very low success rate, with only a 5% chance for epiblats stem cell clusters to form the embryo structure. But the cardboard system can control the culture medium to increase the ratio to 90%.

Each of these devices can produce about a dozen workpieces in just a few days. If scientists build a " nursery " with many devices at the same time, they can create hundreds or even thousands of embryos.

If scientists build a "nursery" with many of these microfluidic devices at the same time, they can create hundreds or even thousands of embryos.

Biologists will have a stronger "power"

Fu called this step " an exciting new milestone for the emerging field [early embryonic research ]." Micro-liquid equipment will equip scientists with a strong " power " , to look at human development from the first moments of life.

" Human embryo-like structures have huge potential, promising to open up what we call the black box of human development ," Fu said.

The black box he mentioned was the first time after sperm fertilized an egg. It was the time when the embryo was in the woman's body and it was almost impossible for scientists to intervene to study.

Unfortunately, it is this period between two and four weeks after conception that is the time when many miscarriages occur, and serious birth defects can form.

Now, with his new device, Fu hopes to provide scientists with a tool to learn about important health issues, including how to prevent birth defects and miscarriage.

In addition, researchers can use this large amount of embryos to screen drugs, helping to determine whether the drug is safe for pregnant women or not. " Such studies can lead to a lot of good things ," Fu said.

Agreeing with him, Ali Brivanlou, an embryologist at Rockefeller University in New York, said: " It is a great improvement, which will bring us the knowledge of early human development. We are opening the window to look at the embryonic development stage that we have never seen before. These insights are truly the Holy Grail of the human embryo . "

Ethical Concerns: Which Human Embryos Synthesis?

Other scientists and bioethics also agree with Brivanlou and Fu. But they further warn that his research poses very sensitive issues.

" The team needs to be very careful not to model all aspects of the developing human embryo, in order to avoid the concern that this embryo model could one day become a child. if you put it in your mother's womb , "said Insoo Hyun, a biologist at Harvard Medical School.

Due to such concerns, Fu said that he had to deliberately create incomplete embryos, trying to drive it to avoid developing into complete human embryos. These combinations are "only part of the human embryo ", Fu said. They are deficient in important structures, such as the early stage of the placenta and the yolk sac that provides nutrition to the embryo.

" I understand that there are people who are very sensitive when you see that you can massively produce organized embryonic structures. People will be concerned. I understand that. I guess we are approaching the boundaries." Fu said.

" But I want to make 100% clear that we have no intention of creating a synthetic structure like a complete human embryo. We have no intention of doing that."

Fu said that he had to deliberately create incomplete embryos, trying to drive it to avoid developing into complete human embryos.

Praised Fu's approach, but several other scientists also stressed concerns about the boundary breaking. " Is that an early version of the Frankenstein model? " Says biologist Daniel Sulmasy at Georgetown University. "Someday you can take different parts and put them together to try to create a creature."

" If someone tries to do that, even at the first stage of embryonic development, and then they (don't destroy the embryo) try to keep it growing longer, that would be a problem. " , Sulmasy said.

Rapid advances in human embryogenesis have prompted the International Society for Stem Cell Research to issue an assessment, prescribing guidelines and limiting research in this area.