Stem Cells: The Building Blocks of Life
Medical Risks & Complications
There is no doubt that stem cells can potentially treat many medical conditions. Unfortunately, stem cell therapies may come with risks that can often be life-threatening. When developing new treatments, scientists must account for any unwanted risks and side effects.
Graft v. Host Disease (GVHD)
After an allogeneic stem cell transplant, in which a patient receives stem cells from another individual, the transplanted stem cells view the patient's body as a foreigner and begin attacking it. GVHD comes in two forms: acute, which develops immediately after the transplant, and chronic, which develops about three months after the transplant. The severity of this condition varies from mild to life-threatening. Symptoms possibly include rashes, blisters, nausea, vomiting, dryness of throat and lungs, and yellowing of skin.
Techniques that decrease the risk of contracting this disease involve precise tissue matching, taking immunosuppressive drugs, depleting T lymphocytes from the donor cells, or using cord blood stem cells. Despite these preventive measures, many patients still acquire the disease. Current drugs made to treat GVHD are not always effective and the patient may end up dying.
Tumor Formation
Stem cells, like cancerous cells, have long life spans, resist apoptosis, and can proliferate for long periods. Thus, tumor formation becomes a great concern in stem cell therapies.
As stem cells have great potency, if some stem cells remain undifferentiated in transplant tissue, they can give rise to cells of other tissues. Benign tumors called teratomas form when tissue grows in a region it does not normally belong. Scientists must find a way to prevent stem cells from forming tumors before they can use these therapies on patients.
