Polypeptides for inhibiting complement activation
The invention relates to a polypeptide comprising a C3 convertase effector domain, a C5 convertase effector domain and optionally a terminal complex inhibitory effector domain which is resistant to deregulation by physiologic FHR-Proteins and has a dimerization motif, and to its therapeutic use.
1. A method of treating or preventing a disorder related to or associated with the complement system, which comprises administering to patient in need thereof, a polypeptide comprising an inhibitory C3 convertase effector domain and an inhibitory C5 convertase effector domain.
2. The method according to claim 1 , wherein said disorder related to or associated with the complement system is selected from the group consisting of atypical hemolytic uremic syndrome (aHUS), thrombotic microangiopathy (TMA), C3 glomerulopathy (C3G), IgA nephropathy, systemic lupus erythematosus nephritis, transplant rejection, paroxysmal nocturnal hemoglobinuria (PNH), age-related macular degeneration (AMD), infectious diseases, sepsis, SIRS, trauma injury, ischemia/reperfusion damage and myocardial infarction.
3. The method of claim 1 , wherein said inhibitory C3 convertase effector domain confers C3 convertase inhibition by decay-accelerating and cofactor activity.
4. The method of claim 1 , wherein said polypeptide has decay-accelerating and cofactor activity.
5. The method of claim 1 , wherein said inhibitory C3 convertase effector domain is a fragment of Factor H (FH).
6. The method of claim 1 , wherein said inhibitory C3 convertase effector domain comprises Short Consensus Repeats (SCRs) 1 to 4 of FH.
7. The method of claim 1 , wherein said inhibitory C3 convertase effector domain comprises SCRs 1-4 of FHR2.
8. The method of claim 1 , wherein said inhibitory C5 convertase effector domain is a fragment of Factor H-related protein 1 (FHR1).
9. The method of claim 1 , wherein said inhibitory C5 convertase effector domain comprises SCR1 and SCR2 of FHR1.
10. The method of claim 1 , wherein C5 activation and cleavage into C5a and C5b is inhibited by binding of the polypeptide to C5.
11. The method of claim 1 , wherein said polypeptide further comprises a domain that is capable of binding to cellular surfaces.
12. The method of claim 11 , wherein said domain that is capable of binding to cellular surfaces comprises SCR19 and SCR20 of FH.
13. The method of claim 1 , wherein said polypeptide is a multimer.
14. The method of claim 12 , wherein said polypeptide comprises at least one dimerization motif from SCR1 of FHR1.
15. The method of claim 1 , wherein said polypeptide is capable of inhibiting TCC (C5b-9) formation.
16. The method of claim 15 , wherein said TCC formation is inhibited by binding of the polypeptide to C5b-6.
17. The method of claim 1 , wherein said polypeptide comprises the structure A-B-C, wherein A is an inhibitory C5 convertase effector domain, B is an inhibitory C3 convertase effector domain, and C is absent or a domain that is capable of binding to cellular surfaces.
18. The method of claim 1 , wherein A and B are fused directly or via a linker.
19. The method of claim 1 , wherein B and C are fused directly or via a linker.