Emphysematous lung damage is irreversible. Its progression can be slowed by giving up smoking. Treatment is aimed at increasing the functional capacity of the lungs and may include bronchodilators, administration of supplemental oxygen, or lung transplantation. Surgical removal of affected lung tissue (lung volume reduction surgery), aimed at allowing healthy areas of the lung room to function, is being studied for its effectiveness and safety. The genetic form is treated with supplemental antitrypsin administered by infusion or by a gene therapy technique that uses T cells (special immune cells that identify diseased or deformed cells) to deliver it to the desired cell sites.