Have you ever wanted to see an extinct animal? Well, you might just be able to in the near future. Colossal Biosciences and their profound team of scientists have broken through a technical barrier most others could not. In 2011, Jeanne Loring and her colleagues created induced pluripotent stem (iPS) cells from the northern white rhinoceros and a monkey called Drill, the first ones made from endangered species. However, they could not succeed in creating elephant cells. Numerous other teams failed while trying to keep the cells alive and called elephant cells to be especially tedious to work with because the previous methods of maintaining iPS cells did not work. Colossal, though, managed to use iPS cells to create Asian elephant cells, the closest relative known today to woolly mammoths, and kept growing them for the cell structure to form an embryonic state.
Eighteen years ago, Colossal Biosciences showed that mouse skin cells could be reprogrammed to act like iPS cells. iPS cells possess the capability to turn into any other animal’s cell type. They are critical to the plans of Colossal to create herds of Asian elephants that are genetically modified to be replicas of woolly mammoths: higher body fat percentages, shaggy hair, longer tusks, and other traits that differentiate mammoths from elephants. Even though establishing elephant cells seems like the most elementary step towards Colossal’s goals, it is the highlight of the team’s struggles. Colossal first ran into the same issues the previous groups had experienced. The method used to create other iPS cells—instructing cells to overproduce—failed to keep the affected cells alive. Another way known to reprogram cells was a chemical cocktail, which again killed them. The team then realized that an anti-cancer gene, TP35, was inhibiting the rapid growth needed. The experiments were repeated, but this time with TP35 dialed down a notch. This turned out to be the turning point of events; it finally worked. The cells were able to create the three germ layers and looked and behaved like iPS cells from other subjects.
The discovery has been long-awaited by the community and will certainly help in creating other animals’ cells; though, Colossal’s plans for constructing a gene-edited Asian elephant rely on cloning technology and not iPS cells. Since cloning is still under heavy research, it’s safe to say that we will have to wait a lot longer until we can see a real-life extinct animal.
