α-1 antitrypsin is
1. an antacid
2. an enzyme
3. used to treat arthritis
4. used to treat emphysema
(4) -antitrypsin is a protease inhibitor that is produced by the introduction of specific sequence of DNA (or genes) which codes for a particular product in the transgenic animals. It is used to treat emphysema as it inhibits the enzymes of inflammatory cells that contributes to the respiratory complications.