Premature use of stem cell therapy could put patients at risk

Unless appropriate safety systems are in place, experts writing in a recent issue of the British Medical Journal (BMJ) warn that premature stem cell therapy use could put many patients at risk of viral or prion diseases.

The use of human embryonic stem cells has been hailed as the next major  step in the battle against serious degenerative disorders, including diabetes and Parkinson's disease. But is it just propaganda? How much hope should  patients invest in this technology?

The lessons of premature application of gene therapy, the devastation  caused by HIV transmission to people with hemophilia, and the crisis  caused by bovine spongiform encephalopathy (BSE) should all be learning  opportunities, the authors pointed out.

Expansion of stem cell cultures could allow a single stem cell line to be  used for many hundreds – if not thousands – of patients, exponentially  amplifying the potential risk of disease transmission from a single  infected donor.

Yet, by April 2006, European Union member laboratories for in vitro  fertilization and laboratories for producing cell lines with therapeutic intent will have to comply with the EU’s Directive on tissues and cells. This will cover selection of donors, testing, and procurement of the starting material  for cell lines, tracking cells from donor to recipient, and reporting of adverse events.

The authors suggested a novel alternative approach whereby the expanded stem cell lines themselves could be tested for a variety of pathogens before  being released. This would provide an additional safety step and offer an alternative in the armamentarium for testing these important donations  for transplantation.

The drive to be the first to produce cell lines for therapy without appropriate controls could compromise safety for recipients and could lead this technology into the realms of quackery, stated the authors. Such fears are already being  realized in India and Russia, where action may be required to limit or prevent the escalating numbers of clinics offering stem cell cures for all sorts of ills.

Stem cell therapy needs to be nurtured safely and methodically to provide  real benefit to patients in the future, they concluded.

SOURCE: Braude, P; Minger, SL; Warwick, RM. “Stem cell therapy: hope or hype?” BMJ 2005;330:1159-1160 (21 May), doi:10.1136/bmj.330.7501.1159.