Cancer and virus-free: Bats' longevity genes could hold clues for human health

Scientists are studying the mechanisms behind bats' immune systems to uncover what they could teach about human longevity. Bats are the longest-lived mammals for their size and have the ability to adapt to viruses and boost their defences. Scientists are now trying to see whether humans can learn anything from bats’ ability to resist viruses and even prevent cancer. A new study published in the journal Nature looked at what these animals can teach about longevity and fighting disease. The findings reveal that the bats' ability to slow ageing and tolerate viruses is genetically linked, suggesting that the same biological 'tricks' protect them from both infections and the decay of old age “Bats have evolved this incredible fitness capacity, this incredible ability to deal with disease and this incredible ability to be able to prevent cancer,” said Juan Manuel Vazquez, author of the study at the University of California, Berkeley. “That means that, by understanding how bats have evolved to do all these things that other mammals haven’t, we can find completely new and unexpected ways of dealing with the normal things that cause human diseases.” For the study, Vazquez travelled to capture, biopsy and release different species of bats. He currently has cell cultures from 259 individuals representing 32 species. He focused on those in the Myotis genus of bats, known for having some of the most extreme adaptations for longevity and disease resistance among mammals. In this group, the Myotis brandtii (Brandt’s bat) can live up to 42 years. How bats resist ageing and cancer By creating high-quality genetic maps for eight different species, the researchers identified the specific biological "tricks" these animals use to survive. One of the most important findings is that long-lived bats have evolved ways to prevent cancer. For example, the little brown bat (Myotis lucifugus) has an enhanced ability to clear out damaged cells before they can cause harm. An example of this is a specific immune factor called PKR, as most Myotis species have evolved extra copies of this gene to fight a wider range of viruses. A different way of fighting viruses Bats act as zoonotic reservoirs — animals that can carry viruses dangerous to humans without becoming ill themselves. Their ability to do this is a result of a specialised evolutionary strategy known as viral tolerance. The research found that while most mammals use "resistance" to fight viruses by attempting to eliminate the pathogen, bats have evolved high levels of viral tolerance. They have developed mechanisms to suppress the damaging inflammation and cellular stress that would normally kill other mammals, which allows the virus to live in their bodies. For RNA viruses, responsible for human outbreaks such as the COVID-19 pandemic, bats tend to change the number of immune genes they have and evolve extra copies to broaden their defence. What this means for human disease Because bats have developed natural solutions to problems like cancer and cellular decay, they provide a roadmap for understanding how these same processes might be managed in humans, the researchers said. Vazquez noted that bats evolved to live for a long time without getting diseases, which suggests we don't necessarily need to look at diseases of ageing and diseases of infection as completely separate fields. “We can look at these bats and try to understand how, in the same way you can improve your immune system to fight off viruses, maybe you can improve your immune system so it doesn’t decline in old age,” he noted. “Or maybe bats can help us find ways to fight off tumors so our immune system doesn’t get tired, and that can also help us deal with other stresses of life and not exhaust our immunity.”