A team of researchers in China has achieved a significant scientific milestone by reporting the live birth of a monkey containing a high proportion of cells derived from a monkey stem cell line. This "chimeric" monkey is composed of cells originating from two genetically different embryos of the same monkey species. While this recurrence had previously been demonstrated in rodents like rats and mice, it had not been achieved in other species. The study has extensive implications such as understanding pluripotency in primates, potential applications in genetic engineering, and species conservation. This research raises the prospect of developing more precise monkey models for the investigation of neurological disorders and other areas of biomedical research.
The research involved cynomolgus monkeys which are commonly used in biomedical studies. The team established nine stem cell lines from cells obtained from 7-day-old blastocyst embryos and enhanced their ability to transform into different types of cells. They injected a specific subset of these stem cells into early monkey morula embryos, resulting in 12 pregnancies and six live births. One live-born monkey and one miscarried fetus were significantly chimeric, with cells derived from the stem cells present throughout various tissues. Those tissues were the brain, heart, kidney, liver, and gastrointestinal tract. The contribution of the stem cells to different tissue types ranged from 21% to 92%, with an average of 67% across 26 different types of tissue. The researchers plan to further investigate the techniques underlying the survival of the embryos in host animals. The aim is to enhance the efficiency of chimera generation in the future.