Peptide redesign for inhibition of the complement system: Targeting age-related macular degeneration.
To redesign a complement-inhibiting peptide with the potential to become a therapeutic for dry and wet age-related macular degeneration (AMD).



We present a new potent peptide (Peptide 2) of the compstatin family. The peptide is developed by rational design, based on a mechanistic binding hypothesis, and structural and physicochemical properties derived from molecular dynamics (MD) simulation. The inhibitory activity, efficacy, and solubility of Peptide 2 are evaluated using a hemolytic assay, a human RPE cell-based assay, and ultraviolet (UV) absorption properties, respectively, and compared to the respective properties of its parent peptide (Peptide 1).



The sequence of Peptide 2 contains an arginine-serine N-terminal extension (a characteristic of parent Peptide 1) and a novel 8-polyethylene glycol (PEG) block C-terminal extension. Peptide 2 has significantly improved aqueous solubility compared to Peptide 1 and comparable complement inhibitory activity. In addition, Peptide 2 is more efficacious in inhibiting complement activation in a cell-based model that mimics the pathobiology of dry AMD.



We have designed a new peptide analog of compstatin that combines N-terminal polar amino acid extensions and C-terminal PEGylation extensions. This peptide demonstrates significantly improved aqueous solubility and complement inhibitory efficacy, compared to the parent peptide. The new peptide overcomes the aggregation limitation for clinical translation of previous compstatin analogs and is a candidate to become a therapeutic for the treatment of AMD.
Department of Bioengineering, University of California, Riverside, CA.
Rohith R
RR
Mohan
Department of Bioengineering, University of California, Riverside, CA.
Andrea P
AP
Cabrera
Department of Bioengineering, University of California, Riverside, CA.
Reed E S
RE
Harrison
Department of Bioengineering, University of California, Riverside, CA.
Ronald D
RD
Gorham
Center for the Study of Macular Degeneration, Neuroscience Research Institute, University of California, Santa Barbara, CA.
Lincoln V
LV
Johnson
Department of Bioengineering, University of California, Riverside, CA.
Kaustabh
K
Ghosh
Department of Bioengineering, University of California, Riverside, CA.
Dimitrios
D
Morikis
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D003165:Complement System Proteins / Q000378:metabolism*; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D020128:Inhibitory Concentration 50; D008268:Macular Degeneration / Q000188:drug therapy*; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*; D010456:Peptides, Cyclic / Q000494:pharmacology / Q000627:therapeutic use; D011817:Rabbits; D012995:Solubility
D010455:Peptides; D010456:Peptides, Cyclic; C111828:compstatin; D003165:Complement System Proteins