SuperBat
The Australian Black Flying Fox (Pteropus alecto) is a black fruit bat with a wingspan larger than 1 meter, making it one of the largest bats in the world. These bats are extremely unique because they are carriers for over 100 diseases, but never get sick from any of them. Many of these diseases like MERS and Ebola are very dangerous, even fatal to humans. Somehow, bats seem to be immune to all of them.
The Commonwealth Scientific and Industrial Research Organization (CSIRO) of Australia has been studying these Australian bats and their unique genes, which allow their immune system to be active 24/7. They recently completed sequencing the first gene map of the Type 1 interferon region in P. alecto, which is key to understanding how bats can coexist with viruses in their body. Sequencing this region has shown that the bats’ immune system is very different than the human immune system, which is only activated after a foreign organism, like a bacteria or virus, enters our body and creates physical symptoms of the disease. Because of this, sometimes it can become very difficult for humans to fight off serious diseases like Ebola.
In P. alecto, however, the immune system works to constantly prevent infection from bacteria, viruses, or parasites. An important part of all mammalian immune systems are interferons. Type 1 interferons are especially important for the initial entry of a pathogen to the body. These signaling proteins are then activated and released by host cells to help fight the pathogen and prevent damage to the body. Type 1 alpha interferons are produced by white blood cells, and their purpose is to inhibit viral duplications and regulate immune response. Humans and other mammals have about 7–18 alpha interferons whereas bats only have three. Even with only about a quarter the amount of interferons as humans, bats are able to control viruses that often kill people. The bat alpha type 1 interferons are constantly heightened, acting constantly even when the bats are free of infection, which helps control infection and prevent DNA damage. In humans, while type 1 interferons are also present, they are unstimulated and seen at low levels until infection enters the body. This acts as a downstream response system instead of immediately providing immunity.
Many scientists are working on developing a better understanding of bat immunity, which may allow for better treatment of human diseases. By manipulating human immune response to deadly diseases, we might be able to respond better to infection in the way bats already do. While human applications would be far in the future, it is clear that the super-immune system of P. alecto holds plenty of promise for future scientific study.
