IMMUNOMODULATION OF PERIPHERAL LYMPHOCYTES BY HORMONES OF THE HYPOTHALAMUS-PITUITARY-THYROID AXIS

The aim of this review is to provide a comprehensive examination of th e current literature describing the immunoregulatory effects on the pe ripheral immune system by the hormones that comprise the hypothalamic- pituitary-thyroid (HPT) axis. This article discusses the effects of th e HPT axis hormones on the peripheral lymphoid tissues and the immune responses mediated by the cells that comprise these lymphoid tissues. Neuroendocrine dysfunction in the HPT axis, either naturally or experi mentally induced, and the resulting immune dysfunction are also discus sed. Emphasis in this article is placed on the most recent study findi ngs and those that provide a unique or novel way of evaluating HPT hor mone effects on the immune system. Our knowledge of the immunoregulato ry effects of the hormones that comprise the HPT axis has grown tremen dously in the last 10 years. As can be seen in this review, the immuno regulatory effects of the HPT axis hormones are quite diverse and infl uence most, if not all, aspects of immune system physiology. The conti nued exploration of the bidirectional circuitry between the immune and neuroendocrine systems may allow for development of appropriate proph ylactic procedures that prevent dysfunction in both systems. (C) 1997 Elsevier Science Ltd.