Psychoneuroimmunology: Psychological stress effects on the immune function in healthy human subjects

Psychoneuroimmunology constitues a new interdisciplinary field that studies interactions between behaviour, brain, and the immune system. After a brief description of the functioning of the immune system and the assays employed for its measurement, the main ways of intercommunication between the central nervous system and the immune system are reviewed. These connections make possible an influence of psychological stress on the immune function. The works made with healthy human subjects experiencing naturalistic stressors of varying intensity and duration show several alterations in inmune competence, such as a minor T-lymphocytes proliferative response, a minor natural killer celll activity, and an elevation of antibody titers against latent herpesvirus. These alterations could increase the vulnerability of the organism toinfectious deseases and cancer, but such clinical implications have no yet been firmly established.