A novel approach to attenuate proliferative vitreoretinopathy using ultrasound-targeted microbubble destruction and recombinant adeno-associated virus-mediated RNA interference targeting transforming growth factor-β2 and platelet-derived growth factor-B

Background To date, with the exception of surgery, there are no satisfactory treatments available for proliferative vitreoretinopathy (PVR). Ultrasound‐targeted microbubble destruction (UTMD) represents a new approach for the gene therapy of eye diseases. The present study aimed to investigate the feasibility of the attenuation of PVR by a combinatorial use of UTMD and recombinant adeno‐associated virus (rAAV)‐mediated RNA interference (RNAi) targeting transforming growth factor (TGF)‐β2 and platelet‐derived growth factor (PDGF)‐B. Methods One hundred and eighty rats of the PVR model were averagely divided into six groups (G). The left eyes, respectively, received an intravitreal injection as follows: normal saline (G1), rAAV2‐control small interfering RNA (siRNA) (G2), rAAV2‐TGF‐β2‐siRNA (G3), rAAV2‐PDGF‐B‐siRNA (G4), rAAV2‐TGF‐β2‐siRNA and rAAV2‐PDGF‐B‐siRNA (G5, G6) on day 3 after PVR induction. In G6, a condition of UTMD was used additionally. On days 14 and 28, pathological changes of eye fundus were assessed by ophthalmoscopic and histopathologic examination, and the protein and mRNA levels of TGF‐β2 and PDGF‐B expression were tested using enzyme‐linked immunosorbent assay and a reverse transcriptase‐polymerase chain reaction, respectively. Results The average grade scales of proliferation and the protein and mRNA expression levels of TGF‐β2 and PDGF‐B in G6 were all lower than that in G5 on day 28 (p