As the Trump administration phases out animal experimentation across the federal government, a biotech startup has a bold idea for an alternative to animal testing: unconscious “organ pouches.”
Bay Area-based R3 Bio has been quietly pitching the idea to investors and traders industry publications as a way to replace laboratory animals without the ethical problems that come with living organisms. This is because these structures contain all the typical organs – except the brain, which prevents them from thinking and feeling pain. Co-founder Alice Gilman says the company’s long-term goal is to create human versions that could be used as a source of tissues and organs for people who need them.
For Immortal Dragons, a Singapore-based longevity fund that invests in R3, the idea of replacement is a core strategy for ensuring human longevity. “We believe that replacement is probably better than repair when it comes to treating disease or regulating the aging process of the human body,” says CEO Boyang Wang. “If we can create a non-sentient, headless bodyoid for humans, it would be an excellent source of organs.”
For now, R3’s goal is to produce bags for monkey organs. “The benefit of using models that are more ethical and only look at organ systems would be that the tests would be much more scalable,” Gilman says. (The name R3 comes from the animal testing philosophy known as three Rs— replacement, reduction and refinement — developed by British scientists William Russell and Rex Burch in 1959 to promote humane experimentation.)
Up-to-date drugs are often tested on monkeys before they are given to humans in clinical trials. For example, monkeys have played a key role during the Covid-19 pandemic in testing vaccines and drugs. However, they are also a costly resource, and their numbers in the U.S. are sinking after China banned the export of non-human primates in 2020.
Animal rights activists have long called for an end to research on monkeys, and one of seven federally funded primate research centers across the country signaled would consider closing and turning into a sanctuary amid mounting pressure. So does the U.S. Centers for Disease Control and Prevention ending research on monkeyswhich is part of a wider trend across government to reduce reliance on animal testing.
As a result, Gilman says, there are not enough research monkeys left in the U.S. to conduct the necessary research should another pandemic threat arise. Enter the organ bags.
Organ bags would theoretically have an advantage over existing organ-on-a-chip or tissue models, which lack the full complexity of entire organs, including blood vessels.
Gilman says it’s already possible to create organ bags for brainless mice, although she and co-founder John Schloendorn deny that R3 manufactured them. (For the record, Gilman doesn’t like the term “brainless” for organ bags. “It doesn’t miss anything because we design it to only contain what we want,” he says.) Gilman and Schloendorn wouldn’t say exactly how they plan to create bags for monkey and human organs, but they said they are exploring a combination of stem cell technology and gene editing.
It’s likely that organ sacs could be grown from induced pluripotent stem cells, says Paul Knoepfler, a stem cell biologist at the University of California, Davis. These stem cells come from adult skin cells and are reprogrammed to an embryo-like state. They have the potential to transform into any cell or tissue in the body and have been used to create embryo-like structures that resemble the real thing. By editing these stem cells, scientists could turn off genes needed for brain development. The resulting embryo can then be incubated until it grows into organized organ structures.