Nerves of pain also counteract skin infections

According to the results achieved by a study by the University of Pittsburgh Medical Center, the nerves that make us feel pain are also helpful in contrasting skin infections for which they prevent the spread, a characteristic of the immune system that was previously unknown.

According to the study, published on Cell, pain-sensitive nerves detect certain pathogens and activate a real immune response that also spreads to sites adjacent to the infection, as Daniel Kaplan, a professor of dermatology and immunology and senior author of the study. The results of this study could in particular prove useful for certain skin disorders and autoimmune diseases such as psoriasis.

This research confirms the broader role of the nervous system relegated to pain, a characteristic that has already been underlined by some research but only in recent years.

The researchers performed special experiments on mice. They created a system to activate pain-sensitive neurons in the skin in rodents.

When these neurons were activated in mice infected with Candida albicans, a fungus that causes candidiasis, or with Staphylococcs aureus, a protein called CGRP was released which “recruited” various immune cells.

The nerves not only revealed the presence of fungi or bacteria when the infection started, triggering the immune response, but also sent signals through the spinal column to various other sites in the epidermis close to the point of infection to activate in advance the immune defenses even in places not yet affected, a characteristic the same researchers have defined as “anticipatory immunity.”

The advantage of such a system lies precisely in the use of the nervous system: the latter is the only one that can sort out information of this kind in such a fast and effective way (there is talk of milliseconds compared to the hours that the immune cells would use), as noted by Jonathan Cohen, a student in Kaplan’s laboratory and first author of the study.