Long-term in vivo and in vitro AAV-2-mediated RNA interference in rat retinal ganglion cells and cultured primary neurons.

Viral vector-based expression of small interfering RNAs is a promising tool for gene regulation, both in cultured cells and in animal models. In this study, we analysed the ability of adeno-associated virus-2 to function as an RNAi vector in cultured primary hippocampal neurons in vitro and in retinal ganglion cells in vivo. We demonstrate a long-lasting, highly efficient, and specific down-regulation of gene expression in vivo and in vitro by the use of bicistronic vectors. This is the first evidence of a cell type-specific long-term (more than three-month-long) RNAi in the eye. Furthermore, our results constitute the prerequisite for the use of this technique in models of neurodegeneration and neuroregeneration in vivo and in vitro.