Although the baboons' immune systems evenrualiv killed most of the transplanted cells, some pig DNA survived in one of the baboons for almost a year. Such research may yield ways to prevent inunune rel'ection of organs transplanted from animals, but truly effective measures are probably still some years away. This tactic is feasible only for protecting isolated cells or small packages of tissues, not for whole organs. So it does not address the needs of someone who requires, for example, a new heart or kidney. It should nonetheless be valuable for treating many disorders.
Some investigators are especially eager to treat diabetes with isolated pig islet cells.
Most important, the patient requires major surgery, and the device is apt to become cloned. Less than a gram of encapsulated islets from pigs should supply a diabetic patient with normal amounts of insulin. Although a vast number of cells are involved, the total volume required for these implants would be oray a few dozen cubic centimeters. Eventually the tiny packages would degrade, so no surgery would be needed to remove the old capsules when the supply of islet cells needed to be replenished. The growing sense that xenotransplantation may be near at hand raises some critical concerns.