These new organisms can be used to study embryonic development in its early stages, a great biomedical line of research that could be without ethical problems
A multidisciplinary team from Monash University, Melbourne (Australia), led by Argentine researcher Jose Maria Polo, has published a study in Nature describing how a human pseudo-embryonic structure can be produced from adult skin cells (fibroblasts).
Embryonic development study now could be studied
According to the authors, something similar had already been achieved on four previous occasions, but due to the nature of the cells from which the pluripotent cell structures were obtained, they did not have the appropriate cellular organization to be used as pseudo embryonic biological structures like the ones now produced. The technique used for cell reprogramming is the one proposed by Shinya Yamanaka to produce iPS cells, which is why the authors of this paper call the pseudo embryos produced iBlastocysts. According to them, these organisms can be used to study embryonic development in its early stages, the possible genetic mutations that can occur, how various toxins can act on this biological structure, and help develop new therapeutics that can be used in vitro fertilization.
From a bioethical point of view, it is believed that the iBlastocysts produced can be used for biomedical experiments, since they are not viable human biological organisms. Nevertheless, the concept of non-viability does not seem sufficient to establish that the experimental use of non-viable human embryos is ethical. We are of the opinion that human embryos to which the concept of non-viability is attributed have been assumed to be viable at some point because in order for a thing to cease to be viable, it must previously have been viable. Therefore, from an ethical point of view, we think that these so-called non-viable early human embryos should not be used for biomedical experiments, especially if these experiments entail their death.
This is not the case here, however, given that the organisms produced in the aforementioned article have never been human embryos, but pseudo embryos, with no capacity to develop into living human beings. This is because they lack the necessary cellular organization, spatial-temporal structure and molecular dynamics similar to that of human blastocysts that are required to reach the gastrulation phase and the later stages of embryonic development. Furthermore, their gene regulation program is completely altered, in addition to the epigenetic modifications that are taking place; moreover, since they come from adult somatic cells, their evolution toward a human zygote has no biological foundation.
When could these organisms be used in biomedical experiments?
In this case, however, it seems right to exercise the principle of prudence until the status of pseudo embryos attributed to the organisms produced in the aforementioned study is confirmed by further research. This will be the point when these organisms could be used for biomedical experiments with no ethical restrictions.
Justo Aznar MD PhD and Julio Tudela Pharm PhD
Institute of Life Sciences – Bioethics Observatory
Catholic University of Valencia.