Sunday roast straight from the lab?

Stellan Welin

The New Zealand Bioethics Council may have given a cautious go ahead to xenotransplantation - using animal organs and tissue for human transplantation - but the experience of visiting bioethicist Professor Stellan Welin, of the Linkoping University, in Sweden, suggests it may have a limited future.

The threat of zoonotic diseases - those which cross the species barrier - and organ rejection due to severe immuno-suppression have already proved problematic, he says.

As a member of the ethics committee on human organ donation and the Swedish Gene Technology Board, Welin was heavily involved in proposals for a special agency to be established to oversee xenotransplantation research and govern protocols for tissue storage and use.

"But then it was discovered that pig cells, in the form of porcine endogenous retroviruses (PERVs), can infect human cells in vitro and that basically stopped discussion and research into xenotransplantation, in Sweden at least."

Although it is still not known whether PERVs can infect human transplant recipients or even if they are pathogenic in humans, the threat, together with the failure of pigs and baboons to survive organ transplant experiments beyond a few months, has brought such research to a halt in other parts of Europe too.

Animal transplant experiments may not have moved beyond the earliest phases of rejection, but new research opportunities beckoned.

"Human embryonic stem cells came along in 1998 and caught the fancy of the scientific community, the funders and the public. When xeno got in trouble, human embryonic stem cells were there to be the new promising thing."

Speaking at the recent international Talking Biotechnology conference in Wellington, hosted by Victoria and Waikato Universities, Welin pointed out the difficulties of either predicting or controlling the direction of technologies.

"There's little discussion about new technologies until after they've been introduced and by then there are few opportunities to significantly change the future course. The possibilities for regulation are still there, but not the option to say yes or no to a particular technology."

Human stem cell research is a case in point. The technology which gave rise to it, in vitro fertilisation, had been established and accepted for some time. Research indicates that there is little ethical discussion about IVF today and the stem cell debate centres not so much on the technology but on how it should be regulated to exploit the potential of growing human cells in culture for therapeutic use.

And not just therapeutic use. In his paper "Talking about the Future" Welin made the audacious prediction that if tissue engineering progressed to the stage where specific parts of the body could be "grown" for transplantation, and that is certainly the hope, it was not unrealistic to imagine that animal organs could similarly be grown - for human consumption.

"Why kill a pig in order to eat some pig muscles which can be grown in a lab? Tissue engineering is in its infancy and is rather crude now, but my guess is that when this technology develops, it will prove cheaper to supply nutrients and energy to grow some desirable parts (which do not move around!) than to feed a complete pig with many inedible parts."

For a pastoral country like New Zealand, with an economy still largely dependent on animal agriculture, the implications of such a scenario are staggering, but not altogether unimaginable. New Zealand farmers have always been early to adopt new technologies, which is one reason, in spite of the high cost of transport, they're able to export meat and dairy products to the world so competitively.

The other is the high ratio of arable land to the population. If the need for land was taken out of the meat production equation, in favour of advanced bioengineering resources, the balance would scarcely remain tipped in New Zealand's favour.

The result? Fifty million homeless sheep for a start.

Embryonic stem cells multiply indefinitely and, as the same cells can develop a variety of mature cells for different organs, only small, superior flocks would need to be retained.

Ditto for cows, deer, goats, pigs and poultry. Not only would traditional farms disappear, but secondary industries such as meat processing plants, fencing and fertiliser supplies would be redundant, as would the people needed to run them.

"This would be a loss," admits Welin, "but it is the same kind of loss that occurs whenever new technologies develop. No one makes fire in the old way now that we have matches."

And there could be many benefits. Meat is the most energy- and resource-intensive form of food production and contributes disproportionately to environmental degradation. Engineering meat in laboratories would free up land for crops and forests and possibly allow for reclamation of some habitats to sustain biodiversity.

There would be no need for the proposed "Fart Tax" on animal "emissions" which are largely responsible for the production of the greenhouse gases methane and nitrous oxide.

Laboratories could be set up anywhere, enabling a more equitable distribution of meat, a high-protein food, which is at present an unattainable luxury for many in the developing world.

And if other forms of battery production are anything to go by, production of "lab meat" is likely to be more economical, and therefore more affordable, than traditional farm production.
There's also a strong ethical argument. With meat now neatly dispatched in sanitised cling-wrapped polystyrene dishes, it's easy to forget the realities of the slaughterhouse; yet Welin insists that "killing sentient beings ... is a morally serious thing. The most radical solution to relieve animal suffering in meat production would be to produce meat without animals. It would allow people to enjoy the taste of meat, without killing. That would constitute moral progress".

Alice Shopland of Vegan Vittles accepts that that would answer a lot of questions from an animal rights point of view, but says that eating meat "still seems disgusting to me, although I can't explain why".

And it doesn't do away with the "yuck" factor - people seem more revolted by the concept of meat without animals than disturbed by animals' suffering.

The overwhelming response to Welin's prediction has so far been one of amusement and disbelief, but he maintains that there is a lot to be learned from consideration of such "science fiction" scenarios.