Therapy for the Periphery

The power of optogenetics to improve our understanding of neural circuits is clear. Applying optogenetic techniques to humans, however, remains a goal that is yet to be realized. In my laboratory, we have used optogenetics to manipulate activity in selected neurons of the peripheral nervous system, motivated by the desire to use optogenetics to excite muscle in cases of paralysis, inhibit motor neurons to reduce spasticity, and control nociceptors to treat neuropathic pain. Others have demonstrated that optogenetics can be applied to control neuronal activity in nonhuman primates or have used optogenetics in rodent models to partially restore vision. Translating these exciting results into optogenetic therapies for humans will require successfully overcoming a set of challenges. These include the identification of important disease states that are not adequately addressed by electrical stimulation, pharmacology, or other therapies, demonstration of a potent therapeutic effect of optogenetics in an animal model of the disease state, development and demonstration of safe and effective gene therapy techniques that can transduce selected neurons in humans, development and evaluation of devices to deliver light to transduced neurons in humans, and, finally, management of a clinical trial to evaluate the safety and efficacy of the optogenetic treatment. Meeting these challenges will be difficult but will allow us to harness the power of optogenetics to improve human health.