Nerve Cell Transplants to Treat Chronic Pain

Some people suffer from chronic pain because of damage to their nerve cells. In these cases, the problem seems to be a shortage a signaling molecule called gamma aminobutyric acid (GABA). Now researchers at San Francisco University have reversed chronic pain in mice by transplanting into their spinal chords cells that produce GABA. The researchers

extracted immature precursors of GABA-releasing neurons from the brains of fetal mice, and injected them into adults with injured spinal nerves, whose paws were extremely sensitive to touch. He delivered the neurons to the dorsal horn—a structure in the spine that receives sensory information from around the body. Loss of GABA signalling in the horn is thought to underlie many hard-to-treat pain conditions.

The transplanted neurons survived and gave rise to mature GABA-releasing cells, which formed connections with the local spinal circuits. Within a month, the sensitivity brought on by the rodents’ injured nerves had been completely reversed.

Of course, it remains to be seen whether this will work in people, and it raises the question of where we might get a supply of fetal human nerve cells. Attempts to use engineered stem cells have not worked nearly this well.