Effects of altered glucocorticoid sensitivity in the T cell lineage on thymocyte and T cell homeostasis.
FASEB J
; 16(7): 727-9, 2002 May.
Article
en En
| MEDLINE
| ID: mdl-11923224
ABSTRACT
The homeostatic regulation that controls total thymocyte and peripheral T-cell numbers is not clearly understood. We describe here a direct hormonal influence of endogenous levels of glucocorticoids (GCs) on thymocyte and peripheral T-cell homeostasis independent of indirect systemic effects of GCs. The results were obtained by generating transgenic mice with an altered GC sensitivity targeted to thymocytes and peripheral T cells by increasing or decreasing glucocorticoid receptor (GR) expression specifically in thymocytes and peripheral T cells. A twofold increase in GC sensitivity resulted in a major decrease in thymocyte number, affecting all subpopulations, although single-positive CD8+ cells were less influenced. In the thymus, this was due to increased apoptosis in the organ, whereas proliferation of thymocyte populations was unaffected. In the periphery, a pronounced reduction in T-cell number was seen, demonstrating an effect of endogenous GCs also on T-cell homeostasis. The effects were confirmed in transgenic mice with reduced GR expression, which showed increased thymocyte and T-cell numbers. Thus, our data demonstrate that physiological GC levels are directly involved in controlling the size of both thymocyte and T-cell pools.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Timo
/
Linfocitos T
/
Glucocorticoides
Tipo de estudio:
Diagnostic_studies
Límite:
Animals
Idioma:
En
Revista:
FASEB J
Asunto de la revista:
BIOLOGIA
/
FISIOLOGIA
Año:
2002
Tipo del documento:
Article
País de afiliación:
Suecia