Sustained relief of neuropathic pain by AAV-targeted expression of CBD3 peptide in rat dorsal root ganglion

Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.
Gene therapy (Impact Factor: 3.1). 10/2013; 21(1). DOI: 10.1038/gt.2013.56
Source: PubMed


The Ca(2+) channel-binding domain 3 (CBD3) peptide, derived from the collapsin response mediator protein 2 (CRMP-2), is a recently discovered voltage-gated Ca(2+) channel (VGCC) blocker with a preference for CaV2.2. Rodent administration of CBD3 conjugated to cell penetrating motif TAT (TAT-CBD3) has been shown to reduce pain behavior in inflammatory and neuropathic pain models. However, TAT-CBD3 analgesia has limitations, including short half-life, lack of cellular specificity and undesired potential off-site effects. We hypothesized that these issues could be addressed by expressing CBD3 encoded by high-expression vectors in primary sensory neurons. We constructed an adeno-associated viral (AAV) vector expressing recombinant fluorescent CBD3 peptide and injected it into lumbar dorsal root ganglia (DRGs) of rats before spared nerve injury (SNI). We show that selective expression of enhanced green fluorescent protein (EGFP)-CBD3 in lumbar 4 (L4) and L5 DRG neurons and their axonal projections results in effective attenuation of nerve injury-induced neuropathic pain in the SNI model. We conclude that AAV-encoded CBD3 delivered to peripheral sensory neurons through DRG injection may be a valuable approach for exploring the role of presynaptic VGCCs and long-term modulation of neurotransmission, and may also be considered for development as a gene therapy strategy to treat chronic neuropathic pain.Gene Therapy advance online publication, 24 October 2013; doi:10.1038/gt.2013.56.

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Available from: Hongwei Yu, Jan 30, 2014
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    • "mOsm. To selectively record low voltage–activated T-type currents, a pipette solution that contained fluoride to facilitate high voltage–activated (HVA) I Ca rundown was used (Fischer et al., 2014), which contained (in mM) 135 tetramethylammonium hydroxide, 10 EGTA, 40 HEPES, and 2 MgCl 2 , pH of 7.2, adjusted with hydrofluoric acid with an osmolarity of 300 mOsm. The free concentration for Ca 21 was calculated to be 211 nM using Maxchelator (http://maxchelator. "
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