How a smartphone-sized gadget could free over 100 million animals
Illustration by Tyler Hoehne
According to German biologist Uwe Marx, microscopic artificial organs may soon eliminate the need for animal testing. Marx led a keynote speech and presented his company’s newest “human-on-a-chip” prototypes at last week’s ninth World Congress on Alternatives and Animal Use in the Life Sciences. His company, TissUse, develops microchips made up of circulatory networks, living human cells, and tiny pumps that simulate the architecture and activity of human organs. The technology can be used to test medical treatments and substances without using animals.
This is a big deal. A 2008 study estimated that 115 million animals are used in laboratory experiments each year, a figure clouded by the fact that only 21 percent of countries actually record data on animal testing. Even the U.S. fails to collect data about birds and laboratory-bred mice and rats, which, despite making up over 90 percent of all laboratory animals, aren’t even defined and protected as “animals” under the country’s Animal Welfare Act. Ironically, the act was explicitly designed to regulate fair treatment of creatures used in research.
Though animal testing has existed for millennia—Aristotle dissected animals in ancient Athens, making him one of the world’s first zoologists—the first attempt to legislate and limit the practice was the United Kingdom’s Cruelty to Animals Act 1876, which fined any first offender up to fifty pounds for “performing or taking part in performing any experiment calculated to give pain [to animals].” Laws around the world now mandate widely varying levels of licensing and oversight, with a few notable exceptions: Japan, the world’s second largest user of animals in research, entirely self-regulates its testing, trusting scientists to follow the 3R's principle, a set of ethical guidelines for animal testing developed in the '50s.
The 3Rs principle calls upon scientists to use non-animal methods whenever possible while still achieving the same scientific goals, to use methods that are capable of obtaining the maximum level of information with the fewest number of animals, and to use methods that both minimize pain and enhance the welfare of the animals used. Though it is widely accepted by the international scientific community that scientific and medical pursuit requiring animal testing is desirable as long as animal suffering is minimized, the 3Rs are by no means a definitive ideological stance. Part of the reason animal testing has been so difficult to legislate is because there is so much ethical disagreement.
Abolitionists believe harmful research that doesn’t benefit the individual animal is never morally justifiable, but there are also those who consider denying possible medical benefit to humans as similarly reprehensible. Utilitarians believe an animal’s species carries no weight either way when determining the importance of its suffering. The animal rights philosopher Tom Regan, who first proposed the idea that animals have moral rights, believes that animals have the right to be treated with respect, and thus not to be harmed.
But here’s the thing: Whatever your moral stance, animal testing is ultimately less scientifically reliable than the products and methods hawked by TissUse and academic institutions like Harvard’s Wyss Institute. Though early understanding of anatomy and physiology may have greatly benefited from the study of animals, almost half of all modern drugs that succeed in animal tests cause unexpected side effects when brought into human clinical trials, according to the Sunday Times. Even contemporary alternatives, like individual artificial organs, can’t be trusted without first also testing the drug or treatment on a living animal, to see what happens when organs interact.
And here lies the genius of solutions like TissUse’s, which can currently replicate two-organ interactions. The company aims to complete development of a ten-organ chip by 2017. These solutions offer scientists the opportunity to perform tests on actual living, interconnected human organs and simulate how a living human would react. The organs just happen to be simulations at the smallest possible biological scale. Massive organ farms for all medical research could fit in a warehouse. Mice may finally be able to escape their laboratory maze.