Proposed hemolysis-independent mechanisms of thrombosis in PNH
| 1. Platelet activation through: |
| a. Direct complement activity |
| b. Reactive oxygen species |
| c. Endothelial dysfunction |
| d. Thrombin activation |
| 2. Deficiency of u-PAR (although may only be significant in the presence of red cell microparticles) |
| 3. Deficiency of heparan sulfate |
| 4. Deficiency of TFPI |
| 5. Deficiency of PR3 |
| 6. Endothelial cell activation |
| 7. C5a mediated mechanisms |
| a. Increase in inflammatory cytokines |
| b. Downregulation of ADAMTS-13 |
| 8. Generation of tissue factor and PAI1 from PNH monocytes and neutrophils |
| 9. Decreased levels of protein S |
| 10. Protein C resistance because of increased factor VIII activity |
| 11. Thrombin activation of the complement system perpetuating mechanisms above |
| 1. Platelet activation through: |
| a. Direct complement activity |
| b. Reactive oxygen species |
| c. Endothelial dysfunction |
| d. Thrombin activation |
| 2. Deficiency of u-PAR (although may only be significant in the presence of red cell microparticles) |
| 3. Deficiency of heparan sulfate |
| 4. Deficiency of TFPI |
| 5. Deficiency of PR3 |
| 6. Endothelial cell activation |
| 7. C5a mediated mechanisms |
| a. Increase in inflammatory cytokines |
| b. Downregulation of ADAMTS-13 |
| 8. Generation of tissue factor and PAI1 from PNH monocytes and neutrophils |
| 9. Decreased levels of protein S |
| 10. Protein C resistance because of increased factor VIII activity |
| 11. Thrombin activation of the complement system perpetuating mechanisms above |
PAI1, plasminogen activator inhibitor 1.