Southern CA Stem Cell Scientists Sound Off :  



Recent correspondences published in the October 2006 edition of Nature Medicine 12 (10) 1113-1115 call into question the efficacy of human embryonic stem cells derived or grown in the presence of non-human sialic acid Neu5Gc. A Canadian group from McMaster University claim that, "Serum induced killing of currently available HESC lines is limited and does not correlate with Neu5Gc content," adding, "incorporation of Neu5Gc is unlikely to be of any consideration for future basic or clinical practice." While most researchers would agree that incorporation of non-human proteins into HESC lines is tolerable in vitro, the group from Ontario's accusations that the same is true for clinical applications sparked a resounding backlash from the San Diego scientists that first published their findings on the incorporation of Neu5Gc into HESCs (Nat Med. 2005 Feb;11(2):228-32) and its subsequent immunogenicity (J Immunol. 2005 Jul 1;175(1):228-36.) In their response, Martin et al. site "numerous technical concerns," as well as calling into question their perception of the clinical reality of such therapies and the potential risk involved, stating, "We are mystified as to how the authors could come to the strong conclusion...[It] seems unjustified with regard to the realities of clinical medicine." Even despite numerous concerns by the US-FDA and the EMEA stemming from unpredicted negative side effects from other patient trials gone awry, perhaps the most compelling argument for producing new cell lines devoid of nonhuman byproducts lies in the fact that we can and should always be utilizing our research to develop SAFER treatments for our patients. While the development and mass production of penicillin was a groundbreaking feat, no one would argue now as they would not have then, that we should cease efforts to produce novel antibiotics fine tailored for individual bugs. In much the same way, the original stem cell lines provided by Thompson et al. are simply a basic blueprint for future to improve and fine tailor to fit patient needs. In this case, a simple solution has been suggested, ELIMINATE this POTENTIAL problem. I fully agree with the authors stance to refocus attention, "Rather than on second guessing whether it has any in vivo significance" and encourage other stem cell scientists to continually push FORWARD as they carefully design new ways to treat human disease.

Dustin R Wakeman 9-10-06