Patent ID: 8753639

Claim:
A modified polypeptide capable of reducing the activity, amount, or density of a complement regulatory protein (CRP) on a target cell surface, wherein the polypeptide comprises at least two loop domains with CRP binding affinity and has at least 90% sequence identity to the Ad35 fiber knob sequence of SEQ ID NO:3, wherein the first loop comprises amino acids 81-89 of SEQ ID NO:3 and the second loop comprises amino acids 120-126 of SEQ ID NO:3, wherein the polypeptide comprises at least one of a substitution of a glycine (Gly) for the aspartic acid (Asp) at position 85 of SEQ ID NO:3, a substitution of any amino acid for the threonine (Thr) at position 123 of SEQ ID NO:3, or both.