title: Combined ultrasound-targeted microbubble destruction and polyethylenimine-mediated plasmid DNA delivery to the rat retina: enhanced efficiency and accelerated expression.
abstract: BACKGROUND
  Gene therapy has potential in the treatment of refractory retinal diseases. It is important to develop an effective delivery system in the retina. The present study aimed to investigate the efficacy and safety of ultrasound (US)-targeted microbubble destruction (UTMD)-mediated polyethylenimine (PEI) to the rat retina.
  
  
  METHODS
  Gene transfer was examined by injecting PEI/plasmid DNA (pDNA) with or without microbubbles (MBs) into the subretinal space of rats that were then exposed to US. We investigated enhanced green fluorescent protein (eGFP) expression on flat fundus oculi and performed quantitative analysis. Hematoxylin and eosin staining was used to observe tissue damage.
  
  
  RESULTS
  UTMD significantly enhanced PEI/pDNA transfection efficiency safely by increasing both the transgene expression per cell and the percentage of transfected cells of the retina. PEI/pDNA combined with UTMD significantly increased the number of DNA gene copies and the mRNA level in the retinal pigment epithelium (RPE) and neural retina, respectively, compared to PEI/pDNA alone.
  
  
  CONCLUSIONS
  The present study demonstrates that enhanced and accelerated pDNA expression can be achieved in the retina/RPE cells in vivo by UTMD physical techniques combined with a PEI chemical vector. Our study provides useful information for further in vivo retinal gene therapy work. Copyright © 2016 John Wiley & Sons, Ltd.
authors: Department of Ultrasound, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
authors: Hongli
authors: H
authors: Li
authors: Department of Ophthalmology, The Baoshan Branch Institute of Shanghai, Shuguang Hospital, Shanghai, China.
authors: Jin
authors: J
authors: Qian
authors: Laboratory Animal Centre of Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
authors: Chunfang
authors: C
authors: Yao
authors: Department of Ultrasound, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
authors: Caifeng
authors: C
authors: Wan
authors: Department of Ultrasound, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
authors: Fenghua
authors: F
authors: Li
mesh_terms: D000818:Animals; D004247:DNA / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D018014:Gene Transfer Techniques; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D045423:Microbubbles; D008856:Microscopy, Fluorescence; D010957:Plasmids / Q000235:genetics / Q000378:metabolism; D011094:Polyethyleneimine / Q000378:metabolism*; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000378:metabolism*; D055213:Retinal Pigment Epithelium / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013010:Sonication
chemical_list: C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D011094:Polyethyleneimine; D004247:DNA
keywords: kinetic of expression; microbubble; retina gene therapy; target delivery; transfection efficiency; ultrasound