Scientists are trying to produce artificial organs by in vitro differentiation or 3-dimensional printing ( 1- 3).

Organs generated with autologous cells minimize immune rejection, accordingly obviating the costs of the long-term administration of immunosuppression agents and reducing the risks of infection and tumorigenesis. Using organs derived from the patients’ cells as personalized medicine, is one of the trends in healthcare development. Therefore, finding more resources for organ transplantation is urgently needed.Įmerging stem cell technology is promising for the development of tissue engineering and regenerative medicine as it can provide abundant biological materials. Meanwhile, the traditional culture makes recruitment of organ donors more challenging in China than other countries. In 2015, voluntary donations became the only legitimate source for organ transplants in China.

According to the speech delivered by Huang Jiefu, the Director of China National Organ Donation and Transplantation Committee, although China has become the world’s second largest country for organ transplantation, the 20,201 transplant surgeries are mostly inadequate to meet the demand of over 300,000 organs per year. Even in the US, where over 50% of adults are registered as organ donors, more than 20 patients on the waiting list die every day. However, organ shortage and substantial risk of rejection have limited the development of organ transplantation. Accepted for publication Sep 23, 2019.įor patients suffering from end-stage organ failure, organ transplantation is their only hope for gaining a new life and has saved millions of lives worldwide. 'While human/non-human chimeras involving living or fetal animals have been discussed for nearly 20 years, little to no ethical discussion has focused on putting human cells into non-human blastocysts (let alone non-human primate blastocysts).Keywords: Autologous stem cells embryo complementation gene editing human-animal chimeras organ transplantation Farahan explain in a commentary published alongside the study. 'New research often pushes up against the limits of existing thinking about ethics this research is no exception,' ethicists Henry T.

Philosophical questions are not new in science, but such is the pace of development in research like this, that each successive advancement throws up fresh uncertainties and scientific possibilities that often haven't been considered before. In this case, all the embryos were destroyed within 20 days of their creation, but questions swirl around what would happen if such embryonic organisms were let to live longer, potentially developing the rudiments of a nervous system, or even aspects of consciousness or emotions. 'We are doing the experiments with monkeys in China because, in principle, they cannot be done here because of lack of infrastructure,' one of the study authors, developmental biologist Estrella Núñez Delicado from Spain's Universidad Catolica San Antonio de Murcia told Spanish newspaper El Pais in 2019 when news of the study first broke. While Izpisua Belmonte and his team emphasize that the research was conducted with the 'utmost attention to ethical considerations and by coordinating closely with regulatory agencies', some have suggested these particular experiments may have been conducted in China to get around legal issues that might have prevented the work elsewhere. Using fluorescent tagging, the researchers were able to see that the human cells had successfully integrated in 132 of the macaque embryos, and after 10 days, 103 of the chimeric embryos were still alive and developing.īe that as it may, this kind of research makes many in the scientific community uneasy, meddling with both human life and concepts of animal welfare in ways that some consider either unethical or uncomfortably borderline. In each of the monkey blastocysts studied, 25 human extended pluripotent stem cells (hEPSCs) were injected – a form of stem cell with the ability to contribute to both the embryo and the surrounding tissues that will support its development. To try again with something a little closer to home, Izpisua Belmonte – together with a team led by primate reproduction biologist Weizhi Ji from the Kunming University of Science and Technology in China – conducted new experiments with macaque monkey ( Macaca fascicularis) embryos, injecting them with human stem cells, to gauge how these distant-but-related animal cells might coexist as one. As it happened, much like in similar experiments with sheep-human hybrids, the amount of successfully integrated human cells was very low, suggesting certain incompatibilities between the pig and human biology at a molecular level.

Chimera human