Growth Hormone (GH) Deficient Mice With GHRH Gene Ablation Are Severely Deficient in Vaccine and Immune Responses Against .

The precise impact of the somatotrope axis upon the immune system is still highly debated. We have previously shown that mice with generalized ablation of growth hormone (GH) releasing hormone (GHRH) gene () have normal thymus and T-cell development, but present a marked spleen atrophy and B-cell lymphopenia. Therefore, in this paper we have investigated vaccinal and anti-infectious responses of mice against , a pathogen carrying T-independent antigens.

The Severe Deficiency of the Somatotrope GH-Releasing Hormone/Growth Hormone/Insulin-Like Growth Factor 1 Axis of Mice Is Associated With an Important Splenic Atrophy and Relative B Lymphopenia.

A debate is still open about the precise control exerted by the somatotrope GH-releasing hormone (GHRH)/growth hormone (GH)/insulin-like growth factor 1 axis on the immune system. The objective of this study was to directly address this question through the use of mice that exhibit a severe deficiency of their somatotrope axis. After control backcross studies and normalization for the reduced global weight of transgenic mice, no difference in weight and cellularity of the thymus was observed in mice when compared with C57BL/6 wild-type (WT) control mice.

The Somatotrope Growth Hormone-Releasing Hormone/Growth Hormone/Insulin-Like Growth Factor-1 Axis in Immunoregulation and Immunosenescence.

Most scientific reports debate the thymotropic and immuno-stimulating properties of the somatotrope growth hormone-releasing hormone (GHRH)/growth hormone (GH)/insulin-like growth factor (IGF)-1 axis, but there is still some disagreement about the physiological role of this axis in basal conditions. Moreover, some authors have hypothesized that the physiological role of the somatotrope axis only appears in stressful conditions (such as sepsis or infective and inflammatory diseases). This chapter will provide an extended overview of the expression of the components (signals and receptors) of the somatotrope axis and their properties on cells of the innate and adaptive immune system.

Somatotrope GHRH/GH/IGF-1 axis at the crossroads between immunosenescence and frailty.

Immunosenescence, characterized by complex modifications of immunity with age, could be related to frailty syndrome in elderly individuals, leading to an inadequate response to minimal aggression. Functional decline (i.e.