Moral controversy when Japan allowed the creation of human embryos and mice

This experiment opens up a new future of abundant organ transplants, but moral issues are still controversial despite the Japanese government's permission.

Hiromitsu Nakauchi, a Japanese stem cell scientist, has received official support from the government to create animal embryos containing human cells and transplant them into animal bodies. Earlier this year, the same thing happened but was absolutely banned by the government.

Mr. Nakauchi is currently leading two research groups at Tokyo University and Stanford University, planning to implement the transfer of human cells into rat embryos and use them to implant the mouse's body. The ultimate goal of this study is to remove human organs containing human cells from the animal body and then transplant them back into the human body.

A Japanese scientist is planning to introduce human cells and animal embryos.(Photo: Science Pictures ltd / SPL).

As of March, Japan still strictly prohibits these studies. The rules specify, it is not allowed to feed human cells in the animal embryo for more than 14 days or transplant into an animal uterus. The Japanese Ministry of Education at that time also issued a specific guideline to limit scientists within the framework of the permit.

But now the land of the Sun rises through new laws to help make this study easier. The limits are extended and are expected to be announced by the Japanese Ministry of Education next month.

Animal embryos containing human cells are not too new in developed countries like the US, but they only stop in the laboratory and for a safe period of time. Although not banned in the US, studies of this type are prohibited from receiving funding since 2015.

If successful, this will be a new step of the biomedical technology industry.

Nakauchi said his research with his colleagues was quite slow because of legal problems. Initially, he proposed a 14.5-day embryonic development time for public authorities but he ended his experiment at 15.5 days. Next, he wanted to ask the government for permission to extend this time to 70 days and to work on the pig embryo.

'Although it was slow, I felt it was okay, because I needed time to observe and let the authorities and public opinion secure before the ethical scientific experiments' , researcher Tetsuya Ishii is a colleague at Hokkaido University, in Sapporo, Japan.

Concerned about ethics

Some biomedical ethics are concerned about the possibility of human cells moving away from their original desired trajectory, moving to animal neurons like the brain and having can affect their cognitive ability.

In other words, scientists are concerned about the possibility that a mouse or an animal may inherit the intellect and perception from humans due to the hybridization of human embryonic cells.

Nakauchi said his team considered this and looked carefully at the drawing of the experiment."We try to draw the right path for the cells, I want them to point directly to the pancreas, not the brain or nerve cells ," he said.

Although it is a new and promising idea, it makes moral concerns.

In 2017, Nakauchi and colleagues grafted a mouse's iPS cells with normal pancreas, into the embryo of a mouse that could not produce the pancreas. The result of a ruptured mouse has restored its function and production process normally.

Nakauchi and his team also continued to transplant the pancreas into a diabetic mouse. As a result, organs that excrete and produce cells control blood sugar levels and help mice with diabetes to be cured and cured.

But to do the same thing with the human body is not a simple thing. Nakauchi and colleagues published their study at a science topic talk meeting in Austin, Texas in 2018, where they said they had inserted human iPS cells into an embryo. Self-created pancreas.

Hybrid embryos were raised for 28 days but the results were not satisfactory, too few human cells were developed in them and they were no different from a sheep embryo infected with a virus. Nakauchi shared before the conference that perhaps the genetic distance between sheep and humans is too great.

Currently only the world in Japan is allowed to conduct experiments like this, Nakauchi has returned to his homeland to pay attention to the work. In the short term, he and his team will try to genetically engineer iPS and iPS at different stages of the embryo to determine what actually hinders the growth of human cells in animal embryos.

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