Effects of Altering Heparan Sulfate Proteoglycan Binding and Capsid Hydrophilicity on Retinal Transduction by Adeno-associated Virus
Sean M. Crosson, Antonette Bennett, Diego Fajardo, James J. Peterson, Hangning Zhang, Wei Li, Matthew T. Leahy, Colin K. Jennings, Ryan F. Boyd, Sanford L. Boye, Sanford L. Boye, Mavis Agbandje‐McKenna, Shannon E. Boye, Shannon E. Boye
Abstract
Rationally guided engineering of AAV capsids aims to create new generations of vectors with enhanced potential for human gene therapy. By applying rational design principles to AAV2-based capsids, we evaluated the influence of hydrophilic and hydrophobic amino acid (aa) mutations on retinal transduction as it relates to vector administration route. Through this approach we identified a largely deleterious relationship between hydrophilic aa mutations and canonical HSPG binding by AAV2-based capsids. Conversely, the inclusion of hydrophobic aa substitutions on a HSPG binding deficient capsid (AAV2ΔHS), generated a vector capable of robust rod and cone photoreceptor (PR) transduction. This vector AAV2(4pMut)ΔHS also demonstrates a remarkable ability to spread laterally beyond the initial subretinal injection (SRI) bleb, making it an ideal candidate for the treatment of retinal diseases which require a large area of transduction.