Adenovirus-mediated delivery of CD46 attenuates the alternative complement pathway on RPE: implications for age-related macular degeneration

• Published in: Gene therapy Vol. 18; no. 6; pp. 613 - 621
• Main Authors: Sweigard, J H, Cashman, S M, Kumar-Singh, R
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-06-2011; Nature Publishing Group
• Subjects: 631/250/2501; 631/326/596/2561; 631/378/1689/1626; 631/61/2300; Adenoviridae - genetics; Adenovirus; Adenoviruses; Adult; Age; Alternative pathway; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Animals; Applied cell therapy and gene therapy; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; Biotechnology; Care and treatment; CD46 antigen; Cell Biology; Cell Line; Classical pathway; Complement activation; Complement Membrane Attack Complex - metabolism; Complement Pathway, Alternative - genetics; Complement Pathway, Alternative - immunology; Complement system; Epithelium; Fundamental and applied biological sciences. Psychology; Gene Expression; Gene Therapy; Genetic aspects; Genetic Therapy; Genetic transformation; Genetic Vectors; Health. Pharmaceutical industry; Hepatocytes; Hepatocytes - metabolism; Human Genetics; Humans; Industrial applications and implications. Economical aspects; Lysis; Macular degeneration; Macular Degeneration - genetics; Macular Degeneration - immunology; Medical sciences; Membrane attack complex; Membrane cofactor protein; Membrane Cofactor Protein - genetics; Membrane Cofactor Protein - pharmacology; Membrane proteins; Mice; Nanotechnology; original-article; Retina - embryology; Retina - metabolism; Retinal pigment epithelium; Retinal Pigment Epithelium - immunology; Retinal Pigment Epithelium - metabolism; Rodents; Transfusions. Complications. Transfusion reactions. Cell and gene therapy; United States; CD46; age-related macular degeneration; adenovirus; Virus; Eye disease; Retinopathy; Adenoviridae; Alternative pathway complement; Age related macular degeneration; Gene therapy; Vector
• ISSN: 0969-7128; 1476-5462
• DOI: 10.1038/gt.2011.6

Activation of the alternative pathway of the complement system has been implicated in the pathogenesis of age-related macular degeneration. Membrane attack complex (MAC) has been identified mainly on the Bruch's membrane and drusen underlying the retinal pigment epithelium (RPE). Membrane cofactor protein (CD46) preferentially regulates the alternative pathway of complement. The aim of this study was to evaluate the potential of increasing CD46 expression on RPE cells using an adenovirus as a gene therapy approach to reduce alternative pathway-mediated damage to RPE cells. We generated a recombinant adenovirus vector expressing human CD46 (hCD46) and delivered the vector to murine hepatocytes and RPE cells
in vitro
. After incubation in human serum in conditions in which the classical pathway of complement was blocked, we measured alternative pathway-mediated damage of these cells by quantifying lysis and MAC formation. Adenovirus expressing hCD46 was delivered to the subretinal space of adult mice, and 1 week later, ocular flat mounts were challenged with human serum and the levels of complement-mediated damage was quantified. Adenovirus-mediated delivery of hCD46 localizes to the basal and lateral surfaces of RPE cells where it offers protection from alternative pathway-mediated damage, but not classical, allowing the classical pathway to function unhindered.