Stem Cell Research Must Go Global

A co-ordinated, international effort in stem cell research is an idea whose time has come. Stem cells are unique components of our bodies that confer on certain organs and tissues the capacity for self-renewal. The "embryonic" stem cells that can be grown from microscopic, early-stage embryos left over from fertility treatments have proved particularly exciting for scientists because they appear to be capable of specialising into all body tissues.

Potential applications for stem cells range from treating degenerative brain disease to restoring the capacity of diabetic patients to produce insulin. But a great deal of research will be needed first. Like the hugely successful Human Genome Project, a human stem cell project that transcended national boundaries would accelerate progress in a vitally important field.

The Human Genome Project showed that four main principles underlie successful international collaboration. First, techniques and materials must as far as possible be standardised, so that results can be rigorously compared and repeated. Well characterised stem cell "lines" (each "line" being the cells grown from a different individual or embryo), as well as purified material for culturing them, need to be widely available as benchmarks.

Second, research efforts must complement each other. Co-operative planning allows different teams of researchers to tackle complex problems in parallel while avoiding wasteful duplication of effort. Among other things, this means evaluating which diseases are most amenable to attack and establishing working groups to focus on particular issues.

Third, we have also learnt the value of acceleration - of striving for a tenfold or greater increase in the rate of progress. This will require new technology, including novel instruments for handling and testing living cells, as well as expanded training for aspiring stem cell researchers.

Last - and perhaps most importantly - it is transparency of research findings that drives a co-operative effort. If such a programme is to serve the public good, there must be a sensible balance between disseminating raw data, validating and reviewing research findings, and identifying and protecting intellectual property.

No single country's scientists can unilaterally provide the promised benefits of stem cell research. The scale of the task is simply too great. An international human stem cell project is therefore more than just a timely idea; it is a necessity.

Fortunately there are signs that science funding agencies recognise this. In January, for example, the UK Medical Research Council convened a meeting of international funding agencies to discuss the possibility of an international collaborative approach. This and subsequent discussions have identified some of the main scientific problems, together with the constraints created by different countries' public policies.

A crucial task, for example, would be to establish new embryonic stem cell lines. In part this is because many existing lines have been exposed to contaminants in the form of animal cells or proteins. But it would also be necessary to generate genetically perturbed lines to model genetic diseases or cancers, as well as lines obtained using the genome of adult cells to match a patient's immune system. Some of this research can currently be conducted using public funding in Belgium, Canada, Israel, Japan, Singapore, Sweden or the UK but not in the US. Similarly, extensive animal studies would be needed before any human clinical trials could begin. These studies are more practicable in some countries than in others.

Divergences in public policy are inevitable and can be worked round. However, one of the tasks of any international collaboration should be to establish a shared ethical platform for the use of human tissues in research. The increasing pace of progress will also raise new ethical issues that should be approached internationally. These include the impact of targeting particular diseases in preference to others; and at what point a proposed treatment can progress to human trials.

International co-ordination could also offer more concrete benefits in the form of technical resources. Specifically, a stem cell repository, such as the recently established UK Stem Cell Bank, will serve to archive and distribute cell lines. Additional national repositories may be needed to complement the UK bank and, if so, these should be linked electronically to provide researchers with maximal access. Similarly, there is a need for an internet-based description of all existing stem cell lines, giving information about their history and characteristics. Again, the UK's MRC is taking steps to establish such an international registry.

The potential rewards of a human stem cell project are huge. The massive expansion in research will not only accelerate the clinical promise of stem cells - offering hope for otherwise untreatable diseases - but also give us a more profound understanding of the body's lifelong development as a complex, self-organising system.