Stress and the Immune System: Immunological Aspects of Depressive Illness

Abstract

Anecdotal evidence suggesting a causal relationship between psychiatric illness, environmental stress and a malfunctioning immune system goes back to antiquity. Recently, clinical and experimental studies have established the inter-relationship between neuroendocrine regulation, the immune system and abnormalities in central neurotransmission which may be deranged as a consequence of stressful events. This short review is an attempt to assess the evidence implicating altered immune responsiveness in depression and to consider the impact of different types of environmental stress in triggering the immune malfunction. While these findings are of considerable biological importance, it is presently unclear whether the immunological changes are primary or secondary to the disease states.