Ignacio J. Molina Pineda
Professor of Immunology
The connection between the immune system and the central nervous system has been known, though poorly understood, for some time. In this sense, psychoneuroimmunology, a recent field of research, aims to advance this knowledge.
The work of Lubianiker and others provides data aimed at explaining the well-known placebo effect, that is, the beneficial effect based on expectations that we obtain when receiving an inactive substance. They have been able to demonstrate in humans that reward circuits positively modulate the strength of the response to the hepatitis B vaccine. Thus, the increased activity of a specific brain region leads to a greater production of antibodies against hepatitis B, establishing a direct connection between the brain and the immune system.
In this sense, and alongside the aforementioned placebo effect, the nocebo effect, which is precisely the opposite, is recently gaining relevance. This was illustrated in COVID-19 vaccination trials, in which many volunteers who received an inert substance reported side effects similar to those derived from the vaccine.
It is an important work that begins to clarify the molecular basis that connects the brain and the immune system.