HORMONES, NEUROTRANSMITTERS, AND T-CELL DEVELOPMENT IN HEALTH AND DISEASE

WILSON SAVINO; DANIELLA AREAS MENDES-DA-CRUZ; PEREZ ANA ROSA; VINCENT GEENEN

Frontiers Media SA

Lugar: Laussanne; Año: 2021 p. 110

978-2-88963-026-4

Thymus physiology, T-cell development, and peripheral T-cell homeostasis are controlled bya large variety of soluble molecules and their cognate receptors, targeting both the lymphoidand non-lymphoid compartments. Hormones, neurotransmitters, and cytokines influence thefunctions of distinct microenvironmental cells, including their maturation, survival, and antigenpresentation. Additionally, they affect thymocyte survival, migration and selection, thus shapingthe pool of mature T-cells in the periphery. Importantly, some of these circuits can be affected inpathological states.Beneficial effects of the somatotrope axis on thymopoiesis have been extensively reported. Mostof the data derive from studies carried out in mouse models with multiple pituitary deficiencies(i.e., lacking GH, PRL, and thyrotropic hormones), making it difficult to identify the real effect ofGH on T cell homeostasis. Here, Bodart et al. show a series of studies carried out in GhrhKO mice,revealing the absence of thymic involution (in terms of relative weight or cellularity), accompaniedonly by minor changes in the proportions of thymocyte subsets. Authors also obtained datacompatible with a faster commitment of double negative thymocytes in the thymopoietic processaccompanied by an increased thymic output of naïve T cells, this later observation being consistentwith a reduction of central memory T cells in secondary lymph organs. Taken together, thesefindings point out that the integrity of the GHRH/GH/IGF-1 axis is not required for thymocyteand peripheral T cell homeostasis in basal conditions, although it can influence the splenic B cellcompartment. Overall, these data suggest that GH beneficial effects upon thymus homeostasis (continue...)