Shortage of organs for transplantation – is more research on human–animal chimeras the right approach?
It is time to discuss, once again, the lifting of a moratorium on research. We are not talking about the CRISPR genome-editing moratorium, but about the 20 August announcement by the US National Institutes of Health (NIH) to lift the moratorium on research involving chimeric human/non-human embryos (see BioNews 863). The use of federal funds for this kind of research had been previously banned by the NIH in September 2015.
Although it does not state it explicitly, the NIH announcement seems to have been triggered by Harvard professor George Church's research on growing humanised organ models in non-human animals, namely pigs.
Insoo Hyun, a bioethicist at the Case Western Reserve School of Medicine in Cleveland, Ohio, followed with a perspective piece in PLOS Biology, stating that the benefits of this kind of research are so great that we should no longer hesitate to fund it. He addresses traditional concerns in animal ethics, such as safety, the moral status of the non-human animal (in this case, the human/non-human chimera) and the exploitation of non-human animals in research.
We agree with his precautionary stance, which is consistent with the existing ethical standards for chimera research developed by the International Society for Stem Cell Research in 2007 and which has more emphasis on animal welfare than on speculative concerns about moral humanisation of the human/non-human animal chimera.
Ultimately, we find that Hyun's conclusions that 'most, if not all, of these [traditional] concerns can be reasonably addressed' are plausible. However, Hyun fails to address the elephant in the room: why should we invest significant resources in the creation of humanised animal models in the first place?
Let's take a look at the two main assumptions in Hyun's piece.
'The shortage of human organs for donation is a pressing problem worldwide ... The humanitarian importance of this research is both apparent and urgent. There is currently a dire shortage of organs for transplantation in the United States, leading to approximately 22 deaths per day among patients waiting for organs.'
Hyun is right about the numbers, but we believe that the urgency of the research is not by any means self-evident. What he fails to examine is whether the creation of humanised animal models is the best way to address this pressing matter, and he fails to acknowledge the existence of viable alternatives, such as opt-out policies to increase organ donation from human to human. One notable example is Austria, which has a more than 90 percent organ donation rate; a similar law was approved in Wales in December 2015.
'Given the noble aims of this research, it is puzzling to some why the NIH is so nervous about providing federal funds to researchers with a track record of success in this area.'
When put in this way, it is difficult to object to research that aims to save lives and relieve suffering. The argument goes: we have the opportunity to save lives and we should do that. If we fail to do that, we are equally morally responsible (acts and omissions are morally equivalent). Such beneficence-based arguments are common when it comes to new and emerging science and technologies, but they risk the uncritical acceptance of scientists' assumptions. In this case, the assumption is that the research has the noble aim of solving the shortage of human organs and, as long as precautionary measures are taken to ensure safety and respect for the welfare the animals, then research should be allowed to go ahead.
In the UK, any research of this kind would need a specific licence granted on a case-by-case basis from the HFEA. In 2007, two research groups in the UK (the stem cell biology laboratory directed by Dr Stephen Minger at King’s College London, and the group headed by Dr Lyle Armstrong at Newcastle) applied independently for a licence to the HFEA to carry out interspecies somatic cellular nuclear transfer for the creation of 'cybrids', which were eventually granted after a period of deliberation and public consultation.
These applications, and the research itself, were motivated by the need to create to develop patient-specific embryonic stem-cell lines through interspecies somatic cellular transfer using oocytes derived from non-human animals (rabbits or cows), to avoid the scarcity of human oocytes. According to HFEA rules, research on 'human admixed embryos' can only be conducted in vitro, and these embryos cannot be placed in non-human animals or humans. In spite of the high hopes, and of the HFEA approval, the cybrid experiments did not yield the expected results, in part because of lack of funding (see BioNews 491), and in part because another more promising technology came about – namely, iPS (induced pluripotent stem) cells, discovered by the Nobel-prize winning Japanese scientist Shinya Yamanaka in 2007 (see BioNews 476).
It remains to be seen how much funding research groups working on humanised animal models for organ transplants will be able to attract. But at these early stages of deliberation, it is important to reflect that investing in this research is a deliberate choice that will shape our collective future. By choosing to invest in this kind of research, we are actively deciding to how allocate scarce resources to address the social problem of shortage of human organs for transplants.
While we do not necessarily believe that the existence of viable alternatives should be used to ban humanised animal models outright, it is certainly a matter that deserves ethical attention. We need reflect on the fact that, by ignoring other potential solutions – or at least prematurely supporting one solution over another – we are actively privileging a medical/scientific solution over a political solution of devising and implementing policies to facilitate human-to-human transplants.
Historical reasons to be skeptical of scientific/medical solutions to social problems abound – the sterilisation of those considered a burden to society instead of investing in disability accommodations; the widespread use of Ritalin and Adderall to manage unruly children in schools instead of investing more resources in education; the use of expensive pharmaceutical solutions to epidemics in low-income countries that could be solved with basic public health measures. What we need is further critical reflection. Technical feasibility alone should never drive a change in law and policy.