What are the potential dangers of stem cell treatments?

Stem cell treatments may present various dangers in their use. The more immediate risks include experiencing different symptoms such as fatigue, dizziness, nausea, chills, and headache following the injection of stem cells. These symptoms are typically temporary and not severe in nature. There are also more serious dangers that exist following severe immune responses to stem cell treatments. One example is graft versus host disease (GvHD), in which the graft reacts against the host. GvHd occurs when T cells in the donated stem cells attack the body’s own cells. In specific, this disease occurs because the donor cells recognize the host cells as foreign and begin to attack them. GvHd can occur within months of stem cell transplants, or over years. Symptoms include dry eyes, shortness of breath, jaundice, and dry skin. This disease is considered to be mild and can be treated with medication, but can also be life-threatening; chronic GvHD is the leading cause of mortality among individuals undergoing allogeneic stem cell transplants. Another danger of stem cell treatments is the possibility of tumor formation, due to the potency of stem cells (pluri- or multipotent) and their ability to divide infinitely. Lastly, stem cells pose a risk of transporting harmful agents into the body. The donor-to-recipient transmission of viral, fungal, bacterial, or prion agent may cause life-threatening and fatal reactions in humans. As an example, cytomegalovirus (CMV) is a significant complication in allogeneic stem cell transplants.