نقش پذیری تستوسترون جنین توسعه تیموس را تحت تاثیر قرار داده و منجر به جوان سازی فنوتیپی و مردانه خون محیطی محفظه سلول T در موش ماده بالغ می شود
|کد مقاله||سال انتشار||مقاله انگلیسی||ترجمه فارسی||تعداد کلمات|
|75690||2009||11 صفحه PDF||سفارش دهید||8340 کلمه|
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : Brain, Behavior, and Immunity, Volume 23, Issue 2, February 2009, Pages 294–304
Exposure of female rodents to testosterone in the critical neonatal period produces defeminization/masculinization of the hypothalamo–pituitary–gonadal (HPG) axis, i.e. neonatal androgenization and postpones axis maturation. To address the hypothesis that HPG axis signaling is involved in the programming of thymic maturation/involution and sexual differentiation we studied the impact of neonatal androgenization on thymic cellularity, development of effector and regulatory T cells, and phenotypic characteristics of peripheral blood T lymphocytes in adult rats. A single injection of testosterone on postnatal day 2 postponed thymic maturation/involution as revealed by organ hypercellularity, increased cellularity of the most mature (CD4+CD8− and CD4−CD8+) TCRαβhigh thymocyte and both recent thymic emigrant (RTE) subsets and caused phenotypic defeminization/masculinization of thymic (decreased CD4+CD8−TCRαβhigh/CD4−CD8+TCRαβhigh cell ratio) and peripheral blood T-cell compartments (decreased CD4+RTE/CD8+RTE and CD4+/CD8+ cell ratio). In addition, neonatal androgenization increased the relative and absolute numbers of both CD4+CD25+Foxp3+ and natural killer (NK) regulatory T cells in peripheral blood. These findings, in conjunction with thymocyte overexpression of Thy-1 that is assumed to reduce negative selection affecting self-reactive cell generation, suggest a new relationship between self-reactive and regulatory T cells. In conclusion, our study provides additional evidence for a role of HPG signals (i.e. sex steroids and gonadotropins) in programming the kinetics of thymic maturation/involution and in establishing immunological sexual dimorphism.