June 1, 2011
The brain is directly tied in with the immune system, transmitting messages that controls the inflammatory response in regards to infection, to sepsis and to autoimmune diseases. In 2007, this revelation turned the scientific understanding of the time on its head.
Dr. Kevin Tracey is director and chief executive of The Feinstein Institute for Medical Research. His laboratory was the site of research concerning the vagus nerve and its role in the body’s inflammatory response and disease.
He spoke on their findings at the 2007 Stetten Lecture at the National Institutes of Health in Bethesda, MD.
The hope that sprang from this research was that it would be possible to corral natural healing defenses and reduce sepsis before it does too much damage. Sepsis is the end result when the body unleashes its immune response upon systemic infection. This sepsis can be too efficient for the individual’s good, all too often leading to death.
Tracey has learned that the vagus nerve uses a neurochemical called acetylcholine, to be in direct communication with the immune system. Stimulation of the vagus nerve tells the immune system not to issue forth toxic inflammatory markers.
In 2009, Tracey again presented new findings at the American College of Rheumatology/ Association of Rheumatology Health Professionals (ACR/ARHP) Annual Scientific Meeting in Philadelphia, PA.
It had been previously known that the nervous system is activated by inflammatory mediators via the bloodstream, and through the blood-brain barrier, or by the production of cytokines in the brain. According to an article published in the May 2010 issue of The Rheumatologist, it has now been learned that inflammatory mediators can use the vagus nerve to activate the nervous system.
Dr. Gary Firestein is a professor of medicine, and chief of rheumatology, allergy and immunology, as well as dean of translational medicine at the University of California, San Diego. Research performed by Firestein and his team had shown that the central nervous system senses peripheral inflammation, triggering a series of events that ultimately affects the body’s inflammatory responses.
Tracey and Firestein have been working together to puzzle out more about the connection between the central nervous system and the immune system.
Paul-Peter Tak, MD, PhD, of the Academic Medical Center at the University of Amsterdam, The Netherlands, added his voice and experience as he spoke at the ACR/ARHP meeting. The consensus is that the autonomic nervous system is involved in the regulation of immune responses to inflammatory stimuli.
According to the three researchers, the immune system should no longer be viewed as an island, but rather as an actively involved partner with the central nervous system, in dealing with inflammatory stimuli.
It is possible that therapies for rheumatoid arthritis and other autoimmune diseases may evolve from this new light on the vagus nerve and its greater circle of communication and influence within the body.