effect of stress on the immune system

ABSTRACT

It has been known for many years that mental attributes influence resistance to some diseases. The recently bereaved students preparing for examinations and individuals who are mentally depressed, all show reduced lymphocyte reactivity. The brain, especially the hypothalamus, controls neurotransmitter function of the autonomic nervous system. This influences immune reactivity through ACTH secretion by the pituitary which is regulated by feedback mechanisms of adrenal hormones levels. Consequently, primary and secondary lymphoid organs are affected. Stress can depress T-cell mitogenesis, natural killer [NK] cell activity and interleukin-2 [IL2] production. Cells react to stressful stimuli by synthesising and accumulating a specific group of stress proteins'. They are involved in assembling, disassembling and translocation of certain protein complexes through intracellular membranes. They can also interact with steroid hormone receptors, viral and cellular kinases, actin and tubulin. They have been implicated as being essential for viral replication and assembly of a variety of bacterial viruses. Stress-related thymic atrophy may be responsible for decreased cellular immunity. Profound uncontained stress may indeed cause body systems, including the immune system, to suffer with an increased vulnerability to disease