Cochlear implant pulses deliver DNA for gene therapy

UNSW Professor Gary Housley used electrical pulses from a cochlear implant to deliver gene therapy, successfully regrowing auditory nerves.  Until now, the “bionic ear” has been largely constrained by the neural interface.

In the study, Professor Housley and colleagues used the cochlear implant electrode array for novel “close-field” electroporation to transduce mesenchymal cells lining the cochlear perilymphatic canals with a naked complementary DNA gene construct driving expression of brain-derived neurotrophic factor and a green fluorescent protein reporter. The focusing of electric fields by particular cochlear implant electrode configurations led to surprisingly efficient gene delivery to adjacent mesenchymal cells. The resulting BDNF expression stimulated regeneration of spiral ganglion neurites, which had atrophied 2 weeks after ototoxic treatment, in a bilateral sensorineural deafness model..

Integration of this technology into other “bionic” devices, such as electrode arrays used in deep brain stimulation, could create opportunities for safe, directed gene therapy of complex neurological disorders.