25 January 2010
Karen Devine is an hourly paid lecturer and researcher at the University of Kent, specialising in the law of Obligations, with a particular interest in the social, legal and ethical implications of collecting and using UCB stem cellsAppeared in BioNews 542
Once regarded as nothing more than biological waste, stem cells from UCB have proven to be a suitable alternative to bone marrow in the treatment of blood disorders and cancers, where bone marrow donors fail to exist. Since 1988, UCB transplants have been used in the treatment of many blood disorders and cancers such as Fanconi's aneamia, thalassaemia, immunodeficiency, aplastic anaemia and acute leukaemia. But as Burrowes rightly points out, only a limited number of public banks and stocks of UCB exist, and more units are urgently needed - not only for treatment purposes, but also for research. Compared to other countries, the UK looks like the poor relation in terms of its low stocks and previous lack of commitment to address this issue. Whilst the bill - and the positive response of Health Minister, Gillian Merron, in her commitment to make £10 million of funding available for UCB banking - is very much needed and welcomed, it is important to factor-in an additional consideration that has so far been omitted from this burgeoning debate. However, whilst Burrowes' championing of UCB's worth and the need for a comprehensive national strategy with regard storage and use within the UK are laudable goals, it is necessary to start at the very beginning and consider that before one can store and use UCB, it must first be collected. The collection procedure itself, however, has received scant attention, despite the fact that procuring UCB can promulgate a number of risks.
Since the introduction of the European Union Tissue and Cells Directive (EUTCD) (2004/23/EC), which was transposed into UK law via the Human Tissue (Quality and Safety for Human Application) Regulations in 2007, only fully trained specialist staff are permitted to collect the cells on premises that meet the necessary standards. What this means in practice is that the process of UCB collection should, in theory, pose no problems with regard to the health and wellbeing of the mother and baby, or with regard to the quality or quantity of the cells, because only those deemed competent can facilitate collection. The problem is that UCB collection may not be the 'entirely risk-free' procedure that many private UCB banks purport it to be. The process is carried out during the third stage of labour - a particularly vulnerable phase of childbirth - and one in which requires the attending midwife's full attention. Furthermore, in order to obtain the optimum number of nucleated cells required for a successful UCB transplant, the sample must be procured whilst the placenta remains in-utero and when the cord is clamped early. However, there is evidence to suggest that collecting the cells whilst the placenta remains in situ increases the risk of post-partum haemorrhage in the mother, and that clamping the cord early increases a small risk of blood disorders, intraventricular haemorrhage, and possibly even cerebral palsy in the child. Whilst it is acknowledged that these risks have been contested, particularly with regard to cerebral palsy, the point is that where the evidence remains equivocal, the potential risks, as well as the benefits, should form part of the debate on UCB collection, banking and use. This is of particular relevance to parents who choose to privately bank their baby's UCB because the chance of being able to use one's own UCB sample for transplant purposes is extremely low, and although clinical trials with regard to additional uses for UCB have shown some success, they are still experimental. Essentially, prospective parents need to be aware of the potential risks involved in saving their UCB with a private bank and to weigh up those risks against the potential benefits, particularly where there is no medically indicated reason - such as families with a history of a medical condition - for doing so. However, this can only be achieved after an in-depth study is carried out to produce more precise and un-biased evidence into the real risks involved in the collection process.
Of course, it is less imperative to deploy potentially risky collection techniques in order to maximise UCB volume when the UCB is being donated to a public bank. As donated UCB samples form part of a collective resource, which is made publicly available, the need to procure the optimum number of cells from each donation is not as much of a priority, and therefore ex-utero and delayed cord clamping can be deployed. This certainly adds weight to the arguments advanced by advocates of public UCB storage, especially as the chance of utilising stored UCB is greatly increased when using cells that are biologically un-related to the recipient. That said, assurances need to be made that when making donations, best practice will be followed.
Arguably then, public UCB banking is the way forward, and Burrowes' campaign to educate all expectant families on their ability to donate UCB instead of discarding it at birth, and to raise this issue in Parliament, is to be applauded. However, whilst raising public awareness, the debate needs to be clear about the differences between public and private banking. The concern is that in highlighting the benefits of UCB, parents that do not live within the vicinity of a public bank to be able to donate may be panicked into banking privately, which has its own risks and, of course, may be of little long-term use. Furthermore, until such time as the collection process itself is afforded its rightful place within the UCB debate, and the potential risks involved are properly researched to ensure that the process is 'entirely risk-free', then there will be a void in our full knowledge and understanding, and the uncertainties that surround collection methods in favour of saving UCB will go unanswered. Whilst there is undoubtedly a debate to be had, it should consider all aspects of UCB procurement, banking and use, from the beginning to the end.