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 polypeptide having the structure A-B-C, wherein A comprises SCR1 and SCR2 of FHR1, B comprises SCRs 1 to 4 of FH, and C is absent or a domain that is capable of binding to cellular surfaces.
2. The polypeptide of claim 1 , wherein A and B are fused directly or via a linker.
3. The polypeptide of claim 1 , wherein B and C are fused directly or via a linker.
4. A method of treating atypical hemolytic uremic syndrome (aHUS) or C3 glomerulopathy (C3G) which comprises administering to a patient in need thereof, a polypeptide comprising Short Consensus Repeats (SCRs) 1 to 4 of Factor H FH) and SCR1 and SCR2 of Factor H-related protein 1 (FHR1).
5. A nucleic acid encoding the polypeptide of claim 1 .
6. A plasmid or vector comprising the nucleic acid of claim 5 .
7. A cell comprising the nucleic acid of claim 5 .
8. A method of producing a polypeptide of comprising an inhibitory C3 convertase effector domain and an inhibitory C5 convertase effector domain, which comprises culturing the cells of claim 7 in a culture medium under conditions that allow expression of the polypeptide, and recovering the polypeptide from the cells or the culture medium.
9. The polypeptide of claim 1 , wherein the SCRs 1 to 4 of FH comprises amino acids 19-264 of SEQ ID NO: 1.
10. The polypeptide of claim 1 , wherein the SCR1 and SCR2 of FHR1 comprises amino acids 22-142 of SEQ ID NO: 2.