Transplanting embryonic neurons into the mouse spinal cord seems to alleviate neuropathic pain — chronic pain that arises spontaneously or in response to the slightest touch due to peripheral nerve injury.

In this type of injury, signalling by spinal cord neurons that produce a neurotransmitter called GABA is reduced. João Bráz and his colleagues at the University of California, San Francisco, transplanted GABA-producing interneurons from the mouse embryonic forebrain into the spinal cords of adult mice with peripheral nerve injury. The transplanted cells integrated into the hosts' spinal cord circuitry and eliminated touch-induced hypersensitivity in mice with neuropathic pain, but had no effect in animals with inflammatory pain.

Neuron 74, 663–675 (2012)