Table 2.
Main protease inhibitors in human plasma. Normal concentration and targets
| Inhibitor | Mw | Plasma concentration | Targets (preferred target first) | |
|---|---|---|---|---|
| kDa | mg/L | μM | ||
| C1-inhibitor (C1-INH) | 100 | 240 | 2.4 | C1r, C1s, MASP-1/2, FXIIa, FXIa, kallikrein, plasmin |
| Antithrombin (AT) | 58 | 240 | 4.1 | Thrombin, FXa, C1s, MASP-1/2, FXIIa, FXIa, kallikrein, VIIa, FIXa, plasmin, trypsin |
| α1-Antichymotrypsin | 63 | 490 | 8 | Cathepsin G, chymase, chymotrypsin |
| α1-Antitrypsin (= α1 proteinase inhibitor) | 53 | 2900 | 55 | Elastase, trypsin, chymotrypsin, collagenases, cathepsin G, plasmin |
| α2-Antiplasmin | 68 | 70 | 1 | Plasmin, trypsin, (chymotrypsin, kallikrein, FXa, FXIa) |
| Inter-α-trypsin inhibitor | 180 | 500 | 2.8 | Trypsin, chymotrypsin, plasmin (slow) |
| α2-Macroglobulin | 725 | 2600 | 3.6 | Most proteases of all classes including cathepsins, granulocyte and pancreas proteases, collagenases, kallikrein, FXa, thrombin, and plasmin |