In vivo dynamics of AAV-mediated gene delivery to sensory neurons of the trigeminal ganglia

Chung H Dang,Daniel Stone,Kurt Diem,Pavitra Roychoudhury,Michelle A Loprieno,Martine Aubert,Harshana S De Silva Feelixge,Keith R Jerome

doi:10.1038/s41598-017-01004-y

Abstract

The ability to genetically manipulate trigeminal ganglion (TG) neurons would be useful in the study of the craniofacial nervous system and latent alphaherpesvirus infections. We investigated adeno-associated virus (AAV) vectors for gene delivery to the TG after intradermal whiskerpad delivery in mice. We demonstrated that AAV vectors of serotypes 1, 7, 8, and 9 trafficked from the whiskerpad into TG neurons and expressed transgenes within cell bodies and axons of sensory neurons in all three branches of the TG. Gene expression was highest with AAV1, and steadily increased over time up to day 28. Both constitutive and neuronal-specific promoters were able to drive transgene expression in TG neurons. Levels of vector genomes in the TG increased with input dose, and multiple transgenes could be co-delivered to TG neurons by separate AAV vectors. In conclusion, AAV1 vectors are suitable for gene delivery to TG sensory neurons following intradermal whiskerpad injection.

Highlights

In vertebrates, the tactile, proprioceptive, and nociceptive afferent neurons of the peripheral nervous system that innervate the face all emerge from a tissue called the trigeminal ganglion (TG)
Based on this knowledge we hypothesized that associated virus (AAV) delivery to the scarified eye or by direct injection into the dermis of the whiskerpad might lead to efficient gene delivery to the TG
We found that AAV vector genomes could be readily detected in the TG following whiskerpad injection, but were undetectable or only present at low levels in mice that underwent inoculation through the eye (Fig. 1)

Summary

Introduction

The tactile, proprioceptive, and nociceptive afferent neurons of the peripheral nervous system that innervate the face all emerge from a tissue called the trigeminal ganglion (TG). Several AAV serotypes are able to efficiently transduce neurons in vitro, and AAV has been extensively used in vivo for gene transfer to both the central and peripheral nervous systems (For reviews see refs 10 and 11). Since the DRG and TG are highly analogous tissues, each containing clusters of cell bodies belonging to sensory afferent neurons, we hypothesized that AAV could be used to genetically manipulate sensory neurons within the TG with high efficiency. Injection of AAV serotype 1 (AAV1) led to 25% of neuronal cell bodies expressing the reporter transgene within all branches of the TG This non-invasive AAV delivery route for TG delivery should prove highly useful in future studies of neuropathic pain, peripheral nerve injury, or latent herpesvirus infections

Methods

Results

Conclusion