Signals from nervous system influence immune system, study shows
Posted Apr 07 2010 12:00am
In a discovery that demonstrates a clear link between the mind and body at a molecular level, scientists have shown that a chemical signal which normally allows nerve cells to communicate with each other -to alter sleep cycles, for examplecan also re-direct actions of the immune system.
The research in mice confirms mounting evidence from studies of cultured cells that the nervous system directly influences the immune system.
In the PNAS paper and in the companion paper in the FASEB Journal, the researchers showed that the strength of the VIP signal received by the T cells regulates the balance between two types of immune T cells, Th1 and Th2. Th1 is normally involved with protection from bacterial invasion and other defenses, but Th1 in excess can lead to
Th2 protects from parasitic infections and autoimmunity, but in
excess can lead to allergies. The researchers discovered the effect of VIP on the Th1/Th2 balance by examining the relative production of the Th cells’ protein products, known as cytokines. When the balance is tipped toward Th1 in knockout mice lacking a critical form of a VIP receptor, allergy is suppressed and resistance to some types of infections is boosted, along with other reactions, they found.
The research did not determine if the impact of the neuropeptide VIP is sufficient to change the course of infections, inflammation or autoimmune disease in which T cells are