Table 1.
Transgenic Proteins and Their Potential Uses in Transplantation.
| Function and Transgenic Protein* | Suspected Mechanism |
|---|---|
| Immune cloaking | |
| CD47 (integrin-associated protein)39,40 | Reduces macrophage-mediated toxicity through signal regulatory protein α (SIRPα); “don’t eat me” signal |
| CD95L (Fas ligand)41 | Prevents apoptosis |
| Anti-pCD152 (anti-pCTLA4 antibody)41 | Minimizes effect of porcine cytotoxic T-cell antigen 4 |
| MGAT3 (GnT-III)41 | Humanizes glycosylation |
| HLA-E–β2 M (fusion protein)42 | Prevents natural killer cell attack in a swine leukocyte antigen knockout |
| SIRPα (signal regulatory protein)40 | Reduces macrophage-mediated toxicity (see CD47) |
| TNF-α (tumor necrosis factor α)43 | Prevents apoptosis |
| TRAIL (TNF-α apoptosis-inducing ligand)41 | Prevents apoptosis |
| Complement humanization | |
| CD46 (membrane cofactor protein)44 | Inhibits complement damage |
| CD55 (decay-accelerating factor)41 | Inhibits complement membrane attack complex |
| CD59 (MAC-inhibitory protein)41 | Inhibits complement membrane attack complex |
| Coagulation humanization | |
| CD39 (ecto-NTP diphosphohydrolase 1)41 | Inhibits platelet aggregation |
| PROCR (endothelial protein C receptor)44 | Enhances anticoagulant serine protease protein C |
| TFPI (tissue factor pathway inhibitor)41 | Inhibits factor Xa and tissue factor, minimizing thrombin formation |
| THBD (thrombomodulin)44 | Activates antithrombotic protein C, minimizing clot formation |