In the coming weeks, a volunteer in Boston, Massachusetts, will be the first to trial a new treatment that could end up creating a second liver in their body. And that’s just the beginning—in the months that follow, other volunteers will test doses that could leave them with up to six livers in their bodies.
The company behind the treatment, LyGenesis, hopes to save people with devastating liver diseases who are not eligible for transplants. Their approach is to inject liver cells from a donor into the lymph nodes of sick recipients, which can give rise to entirely new miniature organs. These mini livers should help compensate for an existing diseased one. The approach appears to work in mice, pigs, and dogs. Now we’ll find out if it works in people. Read the full story.
—Jessica Hamzelou
The most popular content on Facebook belongs in the garbage
The most viewed post on Facebook last quarter was a 69 joke, featuring reposted footage from an episode of the TV show Family Feud. The post, originally an Instagram Reel, had more than 52 million views on Facebook, according to Meta’s quarterly report on the most widely viewed content on the platform in the US. It was just one of many spammy meme reposts to feature in Meta’s own list of its top content on the platform.
This quarterly report, first launched a year ago, was created in part so that Meta could tell the story it wanted to tell about Facebook: that its users are not bombarded constantly with extreme political content. But in trying to do so, it has demonstrated something else: the most popular content on Facebook is often awful, recycled generic memes. Read the full story.
—Abby Ohlheiser
Scientists have created synthetic mouse embryos with developed brains
The news: Mouse embryos recently generated from stem cells in a lab show more brain development than any synthetic mouse embryos created previously. While others had created mouse embryos from stem cells, none had reached the point where the entire brain, including the anterior portion at the front, began to develop, according to the researchers.
How they did it: The new model embryos, which bypass the need for sperm or egg cells, were developed in the lab alongside natural mouse embryos. They mirrored the same stages of development up to eight and a half days after fertilization, developing beating hearts and other foundations of organs.
Why it matters: The findings could help scientists learn more about how human embryos develop and provide insights into diseases, as well as providing an alternative to animals for testing. Studying how mouse stem cells interact at this point in development could also provide valuable insight into why human pregnancies fail during the earliest stages, and how to prevent that from happening. Read the full story.