[New data about neuroimmunomodulation and its functional implications]

After a brief presentation of the immune system as sensorial and effector organ, which recognizes and defends against cellular aggressions, the main psychoneuroendocrine components of immune reaction regulation and modulation are shown. Both central nervous structures that control the hormonal emissions, the vegetative innervation of the lymphoid organs as wells as the afferent neurohumoral pathways involved in the making of the self-regulating and neuromodulating circuits of the humoral and cellular immune responses are mentioned. An important position is held by the interrelations between the hypothalamus-pituitary-corticoadrenal gland, the sympathetic-parasympathetic efferent pathways and the chemical messengers (hormones, neurotransmitters, interleukins, neurotrophins) which make possible the bi-directional neuroimmune communication for maintaining the homeostatic balances on this third effector pathway, too. Also experimental proof concerning the ability of central neurons to secrete neuromodulator cytokines and the presence of specific receptors for the various neuroactive molecules within lymphoid organs and circulating lymphocytes are presented. To close, the psychoemotional components of the neuroimmunomodulator circuits are mentioned, using as examples the changes induced by stress generally and oxidative stress in particular.