For all they do protecting the body, immune cells can sometimes do more harm than good by setting off problems such as arthritis and allergies. Now, a study published in Science on May 26 uncovers a new mechanism through which immune cells known as microglia heighten sensitivity to pain: by breaking down the outer covering of neurons in the spinal cord that are involved in processing pain information. This action results in the brain interpreting the signals from those nerves as chronic pain.
In the study, researchers based at McGill University in Canada mimicked nerve injury in 8 to 12-week-old mice and then collected what are known as projection neurons, which transmit signals to distant places in the central nervous system, from a region in the spine that processes pain signals. Using a stain that indicates the presence of a type of outer covering known as perineuronal nets (PNNs) on ...
