Endocrine-immunological homeostasis: the interrelationship between the immune system and sex steroids involves the hypothalamo-pituitary-gonadal axis.

The growing body of evidence, both experimental and clinical supports the concept of multiplicity of endocrine-immunological interactions. Such interrelationship should be viewed as bidirectional: the immune system like other homeostatic mechanisms is subject to regulation by endocrine factors, while vice versa the immune system by itself affects the function of the neuroendocrine system. The gonadal steroids influence immunity acting at two levels: at the level of primary lymphoid tissues or mature immunocompetent cells, and at the level of the hypothalamo-pituitary axis, influencing the release of hormones which by itself also have immunoregulatory properties. Studies indicate that antiestrogens also affect immune response in both agonistic and antagonistic mode of action, especially analyzed in patients with endocrine-responsive tumors related by hormone therapy.