Scientists create mice chimeras with an unprecedented amount of human cells: study

For story suggestions or custom animation requests, contact [email protected] Visit http://archive.nextanimationstudio.com to view News Direct's complete archive of 3D news animations.

RESTRICTIONS: Broadcast: NO USE JAPAN, NO USE TAIWAN Digital: NO USE JAPAN, NO USE TAIWAN
Scientists have engineered mice that have up to 4 percent of their body made of human cells, or the highest amount achieved in human-mice chimeras, according to a study in Science Advances.

To create the chimeras, scientists took human stem cells and chemically suppressed a protein called mTOR for three hours. This forces the cells to revert back to the "naive" state, which enables them to grow inside mice embryos.

As the embryos matured, researchers found the tissues that would become the heart, liver and bone marrow to contain human cells, which were also found in the blood. Science News reports the technology may help scientists to use chimeras as a source for human organs.

Scientists did not detect any trace of human material in the cells that would develop into mice sperm or egg. This eliminates ethical concerns of chimeras capable of reproduction.

RUNDOWN SHOWS:
1. Chimeric mice made out of 4 percent human cells
2. Inhibiting mTOR proteins allows human stem cells to grow in mice embryos
3. Embryonic heart, liver and bone marrow tissue found to contain human cells
4. Human-mice chimera embryonic gametes contain no human cells

VOICEOVER (in English):
"Scientists have engineered mice that have up to 4 percent of their body made of human cells, or the highest amount achieved in human-mice chimeras, according to a study in Science Advances."

"To create the chimeras, scientists took human stem cells and chemically suppressed a protein called mTOR for three hours. This forces the cells to revert back to the 'naive' state, which enables them to grow inside mice embryos."

"As the embryos matured, researchers found the tissues that would become the heart, liver and bone marrow to contain human cells, which were also found in the blood. Science News reports the technology may help scientists to use chimeras as a source for human organs."

"Scientists did not detect any trace of human material in the cells that would develop into mice sperm or egg. This eliminates ethical concerns of chimeras capable of reproduction."

SOURCES: Science Advances, Science News
https://advances.sciencemag.org/content/6/20/eaaz0298
https://www.sciencenews.org/article/mouse-human-chimera-hybrid-embryos