Recombinant adeno-associated virus-, polyethylenimine/plasmid- and lipofectamine/carboxyfluorescein-labeled small interfering RNA-based transfection in retinal pigment epithelial cells with ultrasound and/or SonoVue.

The present study was conducted to investigate the efficacy and safety of ultrasound (US)‑mediated transfection of the type 2 recombinant adeno‑associated virus (AAV) vectors encoding the enhanced green fluorescent protein (EGFP) gene (rAAV), polyethylenimine (PEI)/plasmid EGFP‑N1 (pDNA) or lipofectamine (L)/carboxyfluorescein (FAM)‑labeled small interfering RNA (siRNA) in the human ARPE‑19 retinal pigment epithelial (RPE) cell line, with or without the addition of SonoVue. Cultured RPE cells were exposed to US, with or without SonoVue under different conditions, including variation in the intensity and duration of treatment, and the dose of microbubbles. The effects of ultrasound‑targeted microbubble destruction (UTMD) on the structure of pDNA and the transfection ability of rAAV, PEI/pDNA and L/siRNA were also evaluated. Furthermore, the effect of UTMD on RPE cells was evaluated at 0 and 24 h following UTMD. US‑mediated transfection (USMT) significantly increased L/siRNA transfection efficiency, as measured by the transgene expression per cell and the percentage of transfected cells. UTMD significantly increased rAAV and PEI/pDNA transfer to RPE cells. UTMD‑mediated rAAV or PEI/pDNA delivery was more effective than USMT‑mediated delivery of siRNA. Evaluating cell viability at 24 h post‑UTMD provided more valuable information than immediate evaluation following UTMD. Furthermore, there was minimal cytotoxicity and minimal change to the structure of pDNA under the optimal parameters. UTMD/US may be of use in enhancing rAAV, PEI/pDNA and L/siRNA transgene expression of ARPE‑19 cells in vitro. Studies on the transfection of different nucleotides (such as pDNA and siRNA) and different types of vectors (chemical and biological) mediated by UTMD may provide useful information to guide future in vivo and transfection studies.