The hypothalamic-pituitary-gonadal axis: immune function and autoimmunity

• Published in: Journal of endocrinology Vol. 176; no. 3; pp. 293 - 304
• Main Authors: Tanriverdi, F, Silveira, LF, MacColl, GS, Bouloux, PM
• Format: Journal Article
• Language: English
• Published: Colchester BioScientifica 01-03-2003; Portland Press
• Subjects: Androgens - physiology; Animals; Autoimmune Diseases - immunology; B-Lymphocytes - immunology; Biological and medical sciences; Bone Marrow - immunology; Contraceptives, Oral, Hormonal - adverse effects; Estrogen Replacement Therapy; Estrogens - physiology; Female; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Gonadal Steroid Hormones - physiology; Gonadotropin-Releasing Hormone - physiology; Gonadotropin-Releasing Hormone - therapeutic use; Humans; Hypogonadism - immunology; Hypothalamo-Hypophyseal System - immunology; Immunobiology; Killer Cells, Natural - immunology; Male; Modulation of the immune response (stimulation, suppression); Pregnancy; Sex; Thymus Gland - immunology; Estrogen receptor; Immune response; Androgen; Estrogen; Gonadotropin RH; Autoimmune disease; Review; Hypothalamohypophysogonadal axis; Ovarian hormone; Hypothalamic hormone; Androgen receptor; Hormone releasing factor; Sex steroid hormone; Immune system
• ISSN: 0022-0795; 1479-6805
• DOI: 10.1677/joe.0.1760293

GnRH and sex steroids play an important role in immune system modulation and development. GnRH and the GnRH receptor are produced locally by immune cells, suggesting an autocrine role for GnRH. Experimental studies show a stimulatory action of exogenous GnRH on the immune response. The immune actions of GnRH in vivo are, however, less well established. Oestrogen and androgen receptors are expressed in primary lymphoid organs and peripheral immune cells. Experimental data have established that oestrogens enhance the humoral immune response and may have an activating role in autoimmune disorders. Testosterone enhances suppressor T cell activity. Although there are some clinical studies consistent with these findings, the impact of sex steroids in autoimmune disease pathogenesis and the risk or benefits of their usage in normal and autoimmune-disordered patients remain to be elucidated. There are neither experimental nor clinical data evaluating functional GnRH-sex steroid interactions within the human immune system, and there is a paucity of data relating to GnRH analogues, hormone replacement therapy and oral contraceptive and androgen action in autoimmune diseases. However, a growing body of experimental evidence suggests that an extra-pituitary GnRH immune mechanism plays a role in the programming of the immune system. The implications of these findings in understanding immune function are discussed.