Targeted decorin gene therapy delivered with adeno-associated virus effectively retards corneal neovascularization in vivo

PLoS One. 2011;6(10):e26432. doi: 10.1371/journal.pone.0026432. Epub 2011 Oct 19.

Abstract

Decorin, small leucine-rich proteoglycan, has been shown to modulate angiogenesis in nonocular tissues. This study tested a hypothesis that tissue-selective targeted decorin gene therapy delivered to the rabbit stroma with adeno-associated virus serotype 5 (AAV5) impedes corneal neovascularization (CNV) in vivo without significant side effects. An established rabbit CNV model was used. Targeted decorin gene therapy in the rabbit stroma was delivered with a single topical AAV5 titer (100 µl; 5×10(12) vg/ml) application onto the stroma for two minutes after removing corneal epithelium. The levels of CNV were examined with stereomicroscopy, H&E staining, lectin, collagen type IV, CD31 immunocytochemistry and CD31 immunoblotting. Real-time PCR quantified mRNA expression of pro- and anti-angiogenic genes. Corneal health in live animals was monitored with clinical, slit-lamp and optical coherence tomography biomicroscopic examinations. Selective decorin delivery into stroma showed significant 52% (p<0.05), 66% (p<0.001), and 63% (p<0.01) reduction at early (day 5), mid (day 10), and late (day 14) stages of CNV in decorin-delivered rabbit corneas compared to control (no decorin delivered) corneas in morphometric analysis. The H&E staining, lectin, collagen type IV, CD31 immunostaining (57-65, p<0.5), and CD31 immunoblotting (62-67%, p<0.05) supported morphometric findings. Quantitative PCR studies demonstrated decorin gene therapy down-regulated expression of VEGF, MCP1 and angiopoietin (pro-angiogenic) and up-regulated PEDF (anti-angiogenic) genes. The clinical, biomicroscopy and transmission electron microscopy studies revealed that AAV5-mediated decorin gene therapy is safe for the cornea. Tissue-targeted AAV5-mediated decorin gene therapy decreases CNV with no major side effects, and could potentially be used for treating patients.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Validation Study

MeSH terms

  • Animals
  • Base Sequence
  • Blotting, Western
  • Cornea / blood supply*
  • DNA Primers
  • Decorin / genetics
  • Decorin / therapeutic use*
  • Dependovirus / genetics*
  • Female
  • Gene Targeting*
  • Genetic Therapy*
  • Immunohistochemistry
  • Neovascularization, Pathologic / therapy*
  • RNA, Messenger / genetics
  • Rabbits
  • Real-Time Polymerase Chain Reaction
  • Tomography, Optical Coherence

Substances

  • DNA Primers
  • Decorin
  • RNA, Messenger