Methodology for automated stereotactic delivery of viral vectors to brain specific regions in mice

Traditional stereotaxis has many limitations regarding the efficacy of brain region‐specific targeting of various agents. Our group has successfully established an automated delivery protocol to achieve brain region‐specific targeting. In the present study we used automated stereotaxis to deliver lenti‐ (Lv) and adeno‐associated viral (AAV) vectors containing a neuron‐specific synapsin promoter upstream of red fluorescent protein (SynRFP) or the membrane/lipid raft protein caveolin‐1 (Cav‐1). Two small craniotomies were made lateral to the bregma suture using a V35 electric drill. The injection needle was positioned on top of bregma to define reference point for all subsequent injections under control of the automated Injectomate software. Using immunofluorescence confocal microscopy of 25 μm brain sections, we detected RFP positive neurons in the dentate gyrus and CA3 hippocampal regions 14 d post AAV5SynRFP . Neuron targeted re‐expression of Cav‐1 with LvSynCav1 was detected in the entorhinal cortex of Cav‐1 knockout mice 7 d post. This novel use of an automated stereotactic delivery system allows for brain region‐specific targeting of gene delivery with minimal human error associated with traditional manual guidance. These results have far reaching implications that can extend into several areas of research to combat brain injury and other forms of neurodegeneration. (Supported by NIH)