BACKGROUND: Liver failure occurs when the liver is no longer able to perform its normal synthetic and metabolic functions. The liver is the organ responsible for filtering the blood to eliminate bacteria or other poisonous materials. It also regulates fat storage and blood clotting while producing vitamins and storing essential minerals. The bile produced by the liver helps humans digest food, and the organ itself helps regulate blood sugar levels. A few common causes of liver failure include hepatitis B, hepatitis C, long-term excessive alcohol consumption, hemochromatosis, malnutrition. Acute liver failure is often caused by overdoses of Tylenol, adverse reactions to certain prescription medications, ingestion of poisonous wild mushrooms, or viruses. Symptoms of liver failure include nausea, loss of appetite, fatigue, diarrhea, jaundice, bleeding, abdomen swelling, mental disorientation, sleepiness and coma.

TRADITIONAL TREATMENTS: According to Nelson Fausto, Ph.D., chair of the Department of Pathology at the University of Washington in Seattle, the liver is one of the only organs in the human body that has the unique capacity to regenerate itself. When viruses cause liver failure, supportive care is given at hospitals until the virus runs its course and the liver has a chance to recover. When the liver is unable to recover from failure, physicians try to keep patients alive until a donor liver turns up and a transplant can be performed. This procedure is very successful, but it can take days before a donor liver becomes available.

FUTURE ALTERNATIVES: Due to the shortage of donor livers in the United States, Dr. Fausto and his team of research scientists are trying to identify stem cells in human livers that could be used to help patients suffering from liver failure. "If we find the cell that is a stem cell for the liver, the idea is we can perhaps inject those cells and repopulate livers that have been injured, particularly after acute injury when there is a major destruction of liver cells," Dr. Fausto says. "The idea is if you could have cells that could be introduced into the patient, it could either be a permanent solution [to help the liver regenerate itself] or at least serve as a bridge until transplantation can be done." Dr. Fausto says there are several issues when it comes to implanting liver stem cells in humans, and that scientists are still many years away from conducting the procedure in people. "The main difficulties are immunological reactions against the cells," he says, "because you are adding cells from another individual into that person with the injured liver. The second difficulty is how to introduce those cells into the liver. All of those things [still need] to be worked out."

GROWING NEW BLOOD VESSELS! Dr. Fausto isn't the only one conducting stem cell research that could one day help humans. Thomas Wight, Ph.D., lead study author in the Hope Heart Program at the Benaroya Research Institute in Seattle is attempting to grow artificial blood vessels. "There is a need for artificial blood vessels in many different situation," Dr. Wight says. "One of the principal needs is during kidney dialysis, because blood vessels have to be accessed for dialysis to take place." According to Dr. Wight, blood vessels can become damaged or destroyed when pricked with a needle multiple times, Although blood vessels can be transplanted from other parts of the body, new blood vessels created by scientists would be stronger and easier to control.

REACTIONS: Mari Jo Fraser knows first-hand what it's like to experience acute liver failure, which is why she is excited about the scientific advancements being made. She believes stem cells could hold the key to saving thousands of lives. "It's just unbelievable," Fraser says. "It's exciting to know that so many people are going to be saved. You are not going to have 18,000 or 19,000 people waiting for a liver."