Over 1.5 million individuals sufer from cornea vascularization due to genetic and/or environmental factors, compromising visual acuity and often resulting in blindness. Current treatments of corneal vascularization are limited in efcacy and elicit undesirable efects including, ironically, vision loss. To develop a safe and efective therapy for corneal vascularization, adeno-associated virus (AAV) gene therapy, exploiting a natural immune tolerance mechanism induced by human leukocyte antigen G (HLA-G), was investigated. Self-complementary AAV cassettes containing codon optimized HLA-G1 (transmembrane) or HLA-G5 (soluble) isoforms were validated in vitro. Then, following a corneal intrastromal injection, AAV vec... More
Over 1.5 million individuals sufer from cornea vascularization due to genetic and/or environmental factors, compromising visual acuity and often resulting in blindness. Current treatments of corneal vascularization are limited in efcacy and elicit undesirable efects including, ironically, vision loss. To develop a safe and efective therapy for corneal vascularization, adeno-associated virus (AAV) gene therapy, exploiting a natural immune tolerance mechanism induced by human leukocyte antigen G (HLA-G), was investigated. Self-complementary AAV cassettes containing codon optimized HLA-G1 (transmembrane) or HLA-G5 (soluble) isoforms were validated in vitro. Then, following a corneal intrastromal injection, AAV vector transduction kinetics, using a chimeric AAV capsid, were determined in rabbits. One week following corneal trauma, a single intrastromal injection of scAAV8G9- optHLA-G1+G5 prevented corneal vascularization, inhibited trauma-induced T-lymphocyte infltration (some of which were CD8+), and dramatically reduced myofbroblast formation compared to control treated eyes. Biodistribution analyses suggested AAV vectors persisted only in the trauma-induced corneas; however, a neutralizing antibody response to the vector capsid was observed inconsistently. The collective data demonstrate the clinical potential of scAAV8G9-optHLA-G to safely and efectively treat corneal vascularization and inhibit fbrosis while alluding to broader roles in ocular surface immunity and allogenic organ transplantation.
