Uncertainty over animal organ transplants

The use of animal organs for human transplant operations (xenotransplantation) is unlikely to solve the organ shortage problem in the near future, according to the third annual report of the UK Xenotransplantation Interim Regulatory Authority (UKXIRA). The report highlights problems with long-term rejection of animal organs by the human immune system, and concerns over the transfer of animal viruses to human patients.

'At least five more pig viruses have been identified and we are not sure how important these are', UKXIRA member Professor Herb Sewell told the British Medical Journal last week. Professor Tony Minson of Cambridge University agreed that the climate for xenotransplantation was not optimal, given public concerns over BSE (bovine spongiform encephalopathy)-Creutzfeldt—Jakob disease, foot and mouth disease and genetically modified food. But he said the research should not stop, saying there was a 'massive market and a huge need for what it might offer'. An estimated 6000 people in the UK are currently waiting for an organ transplant.

The report calls for further research into the risk of animal virus infection, but does not support calls for a moratorium on xenotransplantation clinical trials. It concludes that although alternative therapies (such as stem cell therapies) are being developed, 'xenotransplantation may still offer the prospect of a viable treatment within a worthwhile timeframe'.