This work was partially supported with grants from the Oswaldo Cruz Foundation (FIOCRUZ, Rio de Janeiro, Brazil), Brazilian Research Council (CNPq, Brasilia, Brazil), and Centre National de la Récherche Scientifique (CNRS, Paris, France).
Neuroendocrine Control of the Thymusa
Version of Record online: 7 FEB 2006
Annals of the New York Academy of Sciences
Volume 840, NEUROIMMUNOMODULATION: MOLECULAR ASPECTS, INTEGRATIVE SYSTEMS, AND CLINICAL ADVANCES pages 470–479, May 1998
How to Cite
SAVINO, W., VILLA-VERDE, D. M. S., ALVES, L. A. and DARDENNE, M. (1998), Neuroendocrine Control of the Thymus. Annals of the New York Academy of Sciences, 840: 470–479. doi: 10.1111/j.1749-6632.1998.tb09585.x
- Issue online: 7 FEB 2006
- Version of Record online: 7 FEB 2006
Abstract: Thymocytes undergo a complex process of differentiation, largely dependent on interactions with the thymic microenvironment, a tridimensional cellular network formed by epithelial cells, macrophages, dendritic cells, and fibroblasts. One key cellular interaction involves the TCR-CD3 complex expressed by thymocytes with MHC-peptide complexes present on microenvironmental cells. Additionally, thymic epithelial cells (TEC) interact with thymocytes via soluble polypeptides such as thymic hormones and interleukins, as well as through extracellular matrix (ECM) ligands and receptors. Such types of heterotypic interactions are under neuroendocrine control. For example, thymic endocrine function, represented by thymulin production, is up-regulated, both in vivo and in vitro, by thyroid and pituitary hormones, including prolactin and growth hormone. We also showed that these peptides enhance the expression of ECM ligands and receptors, as well as the degree of TEC-thymocyte adhesion. In addition, we studied the thymic nurse cell complex, used herein as an in vitro model for ECM-mediated intrathymic T-cell migration. We observed that T-cell migration is also hormonally regulated as ascertained by the thymocyte entrance into and exit from these lymphoepithelial complexes. Taken together these data clearly illustrate the concept that neuroendocrine circuits exert a pleiotropic control on thymus physiology. Lastly, the intrathymic production of classic hormones such as prolactin and growth hormone suggests that, in addition to endocrine circuits, paracrine and autocrine interactions mediated by these peptides and their respective receptors may exist in the thymus, thus influencing both lymphoid and microenvironmental compartments of the organ.