Spinal Cord Injury and Stem Cell Safety
There are a number of clinics overseas who offer stem cell treatments for spinal cord injuries but these are, as yet, unproven in terms of safety or efficacy. Patients are wise to be sceptical of the sales and marketing tactics employed by such clinics who are often looking to take advantage of vulnerable individuals with no hope of a cure for spinal cord injury. Results of the Geron trial in humans may take a number of years to become available but offer better chances of success for patients than those experimental procedures promoted by stem cell clinics in places like Panama, Germany, and China. Often, these clinics are staffed by inexperienced personnel with little medical knowledge, the stem cells used may be of unknown origin and poorly screened for disease or infection, and patients are offered little in the way of support following treatment if anything should go amiss.
Clinical Trials May be Harmful in Long-Term
The clinical trial for spinal cord injury treated by stem cells is also being called premature however by some researchers who are concerned that the trial risks setting back stem cell investigations if anything goes wrong. The evidence that arises from these treatments may also be called into question as spinal cord injuries are known to be extremely unpredictable, with patients often improving on their own. Attributing that improvement to the treatment is then difficult which can call the research as a whole into question. There have also been concerns raised over the rapidity with which newly injured patients must make a decision to undergo the experimental treatment which they are unlikely to be familiar with prior to their unexpected injury. Geron have addressed these concerns by highlighting their use of an independent advocate assigned to each prospective patient to ensure that the patient fully understands the procedure and possible consequences.
Animal Research Concerns
A further concern is that the research in animal models may not translate to human patients, particularly as many of the animal models used by researchers have deliberately disabled immune systems to prevent rejection of the material. Patients undergoing these experimental procedures may be put on immunosuppressant drugs to prevent rejection of the transplant material, but some scientists, and many staff at overseas stem cell clinics maintain that embryonic stem cells are immunologically inert and that such immune system suppression is not required. Recent research has indicated that embryonic and mesenchymal stem cells can cause immunologic and inflammatory reactions when injected (Buja and Vela, 2010). The finding that stem cells can develop an immune response when placed in inflamed tissue is also of concerns to researchers investigating conditions such as acute trauma to the heart, spinal cord, or other organ or tissue.
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