Xenotransplantation between medicine and society

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XENOME is a five-year research project started in 2006 under FP6 and funded by the European Commission. It brings together experts from several medical fields, immunologists, transplant surgeons, from biology, from the veterinary sciences, and also ethicists, lawyers, sociologists coming from European countries to improve and boost the sciences and technologies involved in xenotransplantation (XT).

According to the definition adopted in the 2001 United States’ guideline – which has provided the basis for all existing regulations – XT has been defined as “any procedure that involves the transplantation, implantation or infusion to a human recipient of organs, tissues or viable cells of animal origin (type A xenotransplant) or the ex vivo contact of human body fluids, cells, tissues or organs with live cells, tissues or organs of animal origin (type B xenotransplant)”.

The main goal of the project is to generate the necessary data to allow XT to progress towards its initial clinical phase. The new data from the research aim at strengthening both efficacy and safety aspects of XT. In particular, at the core of the project, is the establishment of a strong safety framework that may allow progression of XT into the clinic.

The construction of this framework requires that both the scientific and social dimensions are taken into account. On the one hand, it involves the development of technologies enabling the timely diagnosis of infection, the design of a safety plan for an efficacious containment of an untoward infectious event, the breeding of a herd of “clean” source pigs, the inactivation of PERV (porcine retroviruses) sequences, and the provision of the safety-related data derived from long-term in vivo studies in primate xenograft recipients. On the other hand, it offers dedicated attention to safety regulation, risk communication, and public discussion of new technology. In this respect, the project is working toward creation of a strong ethical, social and regulatory framework for xenotransplantation research (and possibly clinical application). This latter framework is the intellectual and practical challenge that the group of XENOME researchers in charge of social, ethical, legal and political aspects is facing.

The reasons for this special focus on safety are related to the history of XT itself. XT has gone through a long history of experimentation, both in scientific and social terms, due to the quite unique challenges that this biomedical technology triggers. Started as a pioneering surgical technique in the 1960s (when newborn Baby Fae was transplanted with a baboon heart and died after 14 days), XT has rapidly grown as a very complex and interdisciplinary field involving a variety of knowledge, approaches, and perspectives encompassing surgery and biotechnology, immunology, and infectious diseases.

The potential threats associated with the transmission of pathogens from one species to another through organ and tissue transplantation were recognized early on and have made XT implementation very controversial. The harmonization between individual and collective rights in matters of health has proved difficult to achieve, and the relation between (uncertain) benefits for patients and (undefined) risks for society is imbalanced. The spreading of HIV in the late 1980s and early 1990s, and later the emergence of other infectious diseases such as SARS and Avian flu, together with the strong opposition to GMOs in Europe, have deeply influenced institutional and public attitudes towards XT. At the end of the 1990s some members of the scientific community and some regulatory systems have called for a moratorium on XT clinical experimentation. That call has also been enforced for a period by some European countries (e.g., The Netherlands and Denmark) and non-European countries (e.g., Australia).

However, major changes have taken place in the last few years on both the scientific and the social side. As far as the scientific approach to XT is concerned, XT has switched its focus from organs to cells and tissues, and is now primarily conceived of and regulated as a pharmaceutical product. Cell therapies and tissue engineered products are not only showing promising results and have been recently tested in some clinical trials around the world (e.g., swine pancreatic islets as a treatment for diabetes), but also may involve less risks than organs. From the social point of view, XT represents one of the first major fields where novel public consultation and public involvement procedures have been explored – especially in Canada and Australia, and more recently in New Zealand – as ways to make democracies more open, transparent, and participatory.

These experiences have certainly helped the subsequent implementation of nano–sciences and nano–technologies whose emergence (and evoked risks) has not given rise – for better or worse – to the same social conflicts that biotechnology had earlier provoked. Also, the democratic exercises previously mentioned have positively contributed, together with the declining fears about new technologies as unique sources of threats, to the quiet and almost unspoken re-emergence of xenobiotic cell– and tissue–therapies.

The social, ethical and legal aspects involved in the regulation and implementation of XT have changed along with these scientific and socio-political developments. XT raises a number of issues ranging from animal ethics to human rights and informed consent to public health and democratic acceptance of technoscientific policies, all of which have been taken into account by different regulatory models in the United States, in Europe, in Canada, and Australia. These models display heterogeneous visions of the relationships among science, citizens and democracy, and deal with rights and risks in peculiar, context-dependent, and culturally-influenced ways. Also, numerous visions of the roles of the public and constructions of different publics are associated with the attempts to make sense of what the citizens think, wish, or are ready to accept, and to fantasize about alternative or complementary conceptions of collective decision-making in science and technology.

Mariachiara Tallacchini teaches Philosophy of Law at the Law Faculty of the Catholic University of Piacenza and Bioethics, Biotechnology and Law at the Faculty of Biotechnology of the State University of Milan. She is a member of the scientific committee of Observa Science in Society.

Observa is conducting a survey on the public perception of xenotransplantation in five European countries as part of the XENOME project.

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