This research study will be evaluating whether liquid nitrogen sprayed on the cells lining the airways (cryotherapy) can reduce the mucus produced in the lungs of patients with chronic obstructive pulmonary disease (COPD). The study involves bronchoscopies, (placement of a lighted, flexible scope into the lungs) under general anesthesia to deliver the treatment to the lungs. The study is randomized such that 2/3 of individuals get the cryotherapy and the other 1/3 get a sham (control) treatment with no cryotherapy. Participants in the sham control group will be evaluated for eligible for cryotherapy at end of year one. The Study duration is 36 months. Those initially randomized to the treatment group, they will have 7 clinic visits and 2 treatment visits. Participants randomized to sham group will have 11 clinic visits and 4 treatment visits.

Individuals with alpha-1 antitrypsin (AAT) deficiency (AAT blood level lower than 11 micro-moles) and emphysema will be invited to participate in this study. This study will determine the impact of IV Alpha-1 proteinase inhibitor (Alpha-1 MP) on the progression of emphysema in patients with AAT deficiency. A participant in this study would receive any one of the following three therapies: 1) Alpha-1 MP dosed at 60mg/Kg, 2) Alpha-1 MP dosed at 120mg/Kg, or 3) Placebo. Once a subject is enrolled into this study, he/she will be randomly selected to receive only one of the above three therapies. Neither the study investigators nor the participants will know the actual therapy being given to the participants. All the study participants will receive serial chest CT scans to determine if their emphysema progresses over the following 3 years. Participants will have the IV therapies given to them weekly, with some infusions given at MUSC and some at home. Safety and side effects of all therapies will be monitored.