Just look at this bleb, this floof, this mouse that’ll grow an extra ear to listen to all your problems. Back in the 1990s the phrase ‘face transplant’ was, at best, technology from a Nicholas Cage movie. Organ and tissue transplants had been around for a spell, but the field had a long way to go.
Rather than trying to match recipients to donor ears- which brings up quite the mental image- scientists conjured what could be described as the most dystopian version of those Disney souvenirs.
Today’s Moment of Science… Mouse ears.
Dr. Charles Vacanti was an anesthesiologist before he joined his brother Jay, likewise a doctor, in researching tissue regeneration. He researched growing cartilage on a biodegradable scaffold in the late 1980s. One of the biggest challenges in growing tissue- after getting it to grow at all- is getting it to grow into something useful. The scaffold material was made of a woven mesh of polyglycolic acid and polylactic acid that would break down harmlessly into water and carbon dioxide in the body. The mesh gives the cartilage cells room to grow.
When Vacanti submitted his work for publication to a top tier journal, he was pretty shocked when it was turned down with the rationale that there were no practical applications for it.
In the absence of the technology to grow a literal middle finger, he’d find the most practical body part to grow.
Vacanti consulted with surgical colleagues and they largely agreed that the ear was the most complicated cartilage structure in the body to fix and recreate. He successfully seeded the biodegradable scaffold with cartilage tissue from a cow, and shaped it into the mold of an ear. Now he just needed to give this jumble of cow knee cartilage somewhere to fulfill its destiny of turning into a real ear.
For this, no ordinary mouse would do.
The nude mouse gets its name from its lack of hair, and because it abides no pants Wednesday. A random mutation back in the 1960s produced this critter. Along with no hair, it has no functional thymus, a vital part of the immune system. This means the nude mouse won’t mount a rejection response to organ and tissue transplants, making it incredibly useful in research.
For purposes of this experiment, it would show proof of concept, that the bioscaffolds could support growth of a cartilage structure in a non-human animal. Did they have to do it this way? Probably not. Did it get the desired effect? Absolutely. The mouse had a goddamn ear growing on its back made of cow. People lost their fucking minds.
‘It’s a violation of animal rights!’
‘Humans are playing god!’
‘Karen wants to speak to science’s manager!’
Charles tried explaining that he only wanted to show that it could be done, not that he wanted a whole ear-backed-mouse army.
According to an interview with Dr. Jay Vacanti, the mouse was perfectly fine after the ear was removed (which I really want to believe). It went on to live a normal lifespan for one of these mice, which is about a year. It wasn’t genetically modified, but the pictures of that mouse have been and will be used in anti-GMO propaganda until the heat death of the universe.
In 2018, a team in China successfully transplanted ears for several children with microtia, a disorder that causes underdeveloped or absent outer ears. The ears were grown using cells of the children’s own cartilage, building on the techniques that Vacanti was told had no practical applications nearly three decades prior.
Four of the Vacanti brothers are doctors and pioneers in the field of tissue regeneration and transplantation. In the decades since then, their research has moved on from the backs of mice and continued to push the field forward. They’ve developed their techniques in growing lung, pancreas, and even nerve tissue. They’ve made bespoke chest plates, tracheas, and even a thumb using a scaffold of coral.
But the only thing named after them is the Vacanti Mouse.
This has been your daily Moment of Science, pretty sure that if this tech becomes open source someone’s gonna grow a pair of Vulcan ears.
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I’m still holding out for a full body transplant.