Recently, elephant (Asian elephant) induced pluripotent stem cells (iPSC) were successfully reprogrammed to reprogram the elephant’s mature skin cells into an embryonic state. This research is an important milestone in realizing its project to resurrect the mammoth. Colossal, founded by George Church and others, is the first company to apply CRISPR technology to species recovery, critically endangered species protection and critical ecosystem reconstruction.

Today, this technology has successfully induced iPSCs in many species, including humans. However, iPSCs in elephants have never been successful.

In this study, the research team first used chemical induction medium, then added the transcription factors Oct4, Sox2, Klf4, Myc +/- Nanog and Lin28, and inhibited the p53 pathway, successfully achieving the most successful elephant induction polypeptide to date. Reprogramming of competent stem cells.

The reprogramming method used in this study differs from commonly used methods, in part because of the complexity of the p53 pathway in elephants. As we all know, p53 is the most important tumor suppressor gene. We humans have two copies of the p53 gene, and more than half of cancer patients have p53 gene mutations. There are as many as 19 copies of the p53 gene in the elephant genome, which may be an important reason why elephants live so long and are so large but do not suffer from cancer.

Furthermore, reprogramming is quite time-consuming and inefficient for higher mammals, and takes even longer for elephants. However, the induced pluripotent stem cells that the study succeeded in expressing multiple core pluripotency factors can differentiate into three germ layers that subsequently give rise to every cell type in the body. These newly reprogrammed induced pluripotent stem cells have been verified by immunostaining, PCR for pluripotency and differentiation markers, transcriptomic analysis, embryoid body and teratoma formation. In addition, this research will also help to deeply understand why elephants do not suffer from cancer, thereby bringing new insights into the research and treatment of human cancer.

Colossal plans to build on this foundation to create the first batch of gene-edited elephants. Through multiple editing and redifferentiation of the above-mentioned elephant iPSCs, it will identify and study the genetic changes required to allow elephants to produce mammoth characteristics, thereby creating a new generation of gene-edited elephants in cells and species. Study cold-adaptive traits in mammoths, such as hair growth and fat storage, at the organ level.

Colossal ultimately hopes to redifferentiate gene-edited iPSCs into sperm and eggs to create embryos that would give birth to mammoths. To avoid using large numbers of elephants to gestate these embryos, Church envisioned using artificial wombs that would not interfere with the natural reproduction of already endangered elephants.

The research team said that after the initial success, there is now more work to be done, and they are currently working on unraveling why cell reprogramming in elephants is so challenging, which will be crucial for obtaining induced pluripotent stem cells more quickly in the future. To enable more advanced tri-lineage differentiation, especially in vitro gametogenesis, to test the full potential of induced pluripotent stem cells.

Once iPSCs can be used to create a model of synthetic elephant embryos, it will also be part of the effort to understand the long and complex cycle of elephant (and mammoth) development and gestation. This is critical to Colossal’s goal of resurrecting extinct species such as the woolly mammoth, as the company relies on using extrauterine development to protect and restore species. What’s more, all of these scientific developments have the potential to expand in the field of developmental biology, with implications well beyond what Colossal is doing now.

George Church said that if there was an award for “hardest to reprogram,” the elephant would win. Regardless, learning how to reprogram will help many other studies, especially on endangered species. This landmark achievement provides insights into developmental biology and the balance between aging and cancer. It opens the door to harvesting gametes and other cell types from rare animals without surgery. It opens the door to establishing links between genes and traits between modern animals and their extinct relatives, including resistance to extreme environments and pathogens.