Antibody That Blocks Pain and Itching Discovered, Study

A newly discovered antibody helps block sensations of pain and itching simultaneously.

A team of Duke University researchers has found a novel antibody that targets the voltage-sensitive sodium channels that regulate flow of sodium ions in the neuron's cell membrane and block the sensation of not just pain but also itching. The study was conducted on mice.

The voltage sensitive sodium channels open and close by reacting to the electric current or action potential of the cells.  The sodium channel responsible for sensing pain is the Nav1.7 subtype.

When the mutation of the human gene that encodes Nav1.7 sodium channel takes place, it either blocks the ability to sense pain or pain hypersensitivity.  But these mutations do not affect other sensations of  touch or temperature.  Due to this the Nav1.7 sodium channel might be a good target to treat pain related disorders without affecting the patient's ability to feel other sensations.

Initially, the team examined the antibody in cultured cells engineered to direct the Nav1.7 sodium channel. The antibody displayed an ability to bind to the channel and stabilize it.

"The channel is off when it is closed," Seok-Yong Lee, assistant professor of biochemistry in the Duke University Medical School and principal investigator of the study explained. "Since the antibody stabilizes the closed state, the channel becomes less sensitive to pain. If this held true in live animals, then the animals would also be less sensitive to pain."

Using a lab mouse model of inflammatory pain and neuropathic pain, the researchers tested the idea. During this the researchers showed that the antibody displayed the ability to act on the Nav1.7 channel and lower the sensation of pain in mice.  The mice receiving the treatment did not display any signs of physical dependence or enhanced tolerance toward the antibody.

"Now we have a compound that can potentially treat both pain and itch at the same time," said Lee. "We hope our discovery will garner interest from pharmaceutical companies that can help us expand our studies into clinical trials. Main goal is to develop a safer treatment for pain and itch as an alternative to opioids, which often cause addiction and other detrimental side effects."

The finding appears online in Cell.