Stem cell research might not be the scientific area with the best public reputation at the moment. I can’t even count the number of times I’ve had conversations in pubs or other random places descending from the casual inquiry about my interests into heated debates about everything that’s wrong with stem cell research. Some particularly insistent opponents actually suggested that stem cell scientists are especially notorious for misconduct and irregular approaches [as a disclaimer, I obviously do not share this view].
A case might be made like this: Only think about the acid bath stem cells scam (that one will always be first). Or the patient who grew a tumour in his spine after a stem cell treatment. Or the three patients who were blinded. And that Italian surgeon who killed people by transplanting artificial tracheae. Ah, wait, that mostly wasn’t about stem cells. Still. What about the South Korean scientist who fabricated his research about somatic cell reprogramming and violated all kinds of ethical regulations to get eggs from women for his research?
There’s a range of scandals to chose from as most have hit the news big time. I am indeed positively surprised that people do not seem to forget about them as easily as they might forget other stories they find in their daily web-feeds. What I usually say in defense of the field (between pints I don’t have enough time to go into details…) is that it is young, extremely challenging and advancing at unprecedented speed given the enormous potential of using an individual’s own, maybe slightly engineered cells for regeneration. So mistakes are being made, because change is simply happening too quickly and regulatory and jurisdictional safety nets take time to be set in place.
The longer and more accurate answer would be that, unfortunately, whenever excitement or commercial interests are taking over, risks might be taken that are too great. Which is why it is crucial to scrutinize every single result from the lab in terms of reproducibility and possible risks to future patients, thoroughly evaluate the safety profiles of potential new treatments and always strictly adhere to ethical regulations. Much of the harm done to patients was the result of so-called “experts” going ahead, ignoring regulations and testing experimental procedures on individuals who were uninformed or too desperate to see what they were getting into. Much has been written about obscure stem cell clinics in operation all over the world, who offer “stem cell treatments” that, at best, have no effect or can leave a patient seriously damaged with unforeseeable consequences. Many initiatives are being taken to educate the public about the risks of these experimental stem cell treatments and it is of course necessary that the media are doing their part by calling attention to issues, such as the above.
But that doesn’t mean that stem cell research is a malicious, deceitful money-making exercise aiming to delude the gullible public. Or that stem cell scientists have a higher tendency to fabricate data. And although the correct way of moving basic science into the clinic – by exercising scrutiny and following regulations from the beginning to the end – means that it will take much longer for clinical trials to become available (we’re not even talking about routine treatments in clinics yet, that’s far into the future), it is the only way to do it. Which means that currently there are no stem cell therapy options routinely available for patients. Except of course bone marrow transplantations which have been a standard of care for decades.
Strikingly, though, this year has brought several genuine advances in clinical trials – the precursor to real clinical application. And that is where we are currently noticing the powerful potential of stem cell treatments for human patients. Two big breakthroughs happened this year:
Masayo Takahashi and her team at RIKEN in Japan have managed to successfully transplant retinal cells into a patient with macular degeneration, a very severe eye disease. They derived these cells from the patient’s own skin via reprogramming skin fibroblasts into induced pluripotent stem cells and then further differentiating them into retinal cells. After one year follow up the transplanted tissue remained intact and visual acuity had not worsened. What is interesting about this study is that they originally also had a second patient who was supposed to undergo the procedure. However, during the extensive safety testing they did prior to transplantation, the authors found genetic mutations in the patient’s reprogrammed cells and decided against the surgery. This is an excellent example of correct scientific procedure. And very much in contrast to what happened during an unregulated experiment performed by a stem cell clinic, in which uncharacterised adipose-derived “stem cells” were injected into three patients with macular degeneration and led to complete loss of vision in all of them.
Michele De Luca and his team in Italy performed the second study that I want to highlight, which was published a week ago and completely transformed the life of a patient. In this case the scientists reconstructed the skin of a 7 year old boy who was suffering from a debilitating genetic skin disease called junctional epidermolysis bullosa, which caused him to lose 80% of his skin. The scientists cultured the patient’s own skin cells in the lab and genetically corrected the mutation that induced skin fragility and blistering and then gradually, over four months, transplanted several patches of skin grafts onto the boy to eventually regenerate the entire skin on his body. During a 21 months follow-up they confirmed that the regenerated skin remained robust and did not develop any more blisters. It also has to be added that this work was based on a strategy from an earlier phase I/II clinical trial that had already confirmed successful engraftment of transgenic skin but had failed to improve the patient’s quality of life.
Successful therapies like these underline the enormous promise stem cells hold for the future of regenerative medicine, especially in areas not yet accessible by conventional medicine. Besides eye and skin diseases, clinical trials are also underway in Parkinson’s Disease, Alzheimer disease, ALS, heart disease, spinal cord injury, diabetes and more. Many of these trials are in early stages, e.g. to evaluate safety and efficacy of the tested cell populations, but with time we will hopefully hear more success stories. I for one find it very exciting to be able to follow a scientific discipline on its move out of basic science into the clinic.
Interested in stem cell trials?
For all of you looking for reliable information about stem cell therapies I can recommend the website closerlookatstemcells.org, which is maintained by the International Society for Stem Cell Research (ISSCR), the leading society in this area. Over the years the ISSCR has spearheaded many initiatives to define and improve scientific and ethical regulations in stem cell research. A list of all registered trials worldwide can be found on clinicaltrials.gov (typing disease name + stem cells will list ongoing stem cell trials). The NIH also provides many helpful resources on how to find a clinical trial and what to consider before making a decision. The golden rule in all of this: beware of stem cell clinics and experimental procedures that are not approved by regulatory authorities, e.g. the FDA. Another helpful list of points to consider can be found on the Niche blog, which also does a great job at generally keeping track of stem cell clinic and commercial quackery.