Autoimmune regulator (Aire) is essential in the perinatal period to prevent the multiorgan autoimmunity. Here we show that Aire-regulated single positive thymocyte trafficking in neonatal period is critical for thymic egress. Reduced thymic emigration was found in Aire-/- mice during neonatal period, leading to enhanced homeostatic expansion of peripheral T cells as early as 2 weeks of age. In ...

Cells originating from the thymus of newborn mice were fused with mouse oocytes using polyethylene glycol. The behaviour of thymocyte nuclei was studied in non-activated metaphase II oocytes, and in oocytes activated in vitro with ethanol. In non-activated oocytes all thymocyte nuclei undergo premature chromosome condensation with individualization of chromosomes; the chromosomes form separate ...

With the use of cultured human thymic epithelial (TE) cells, we have previously shown that thymocytes bind to TE cells in suspension in a rosette-forming assay. To identify cell surface molecules involved in human TE-thymocyte rosette formation, we assayed a large panel of monoclonal antibodies for their ability to inhibit rosette formation. We found anti-CD-2 (LFA-2, T11), and anti-LFA-3 antib...

The thymus in mice lacking both the receptor tyrosine kinase c-kit and the common cytokine receptor gamma chain (gamma(c)) is alymphoid because these receptors provide essential signals at the earliest stages of thymocyte development. The signals transduced by these receptors potentially regulate proliferation, survival, or differentiation, but the contribution of each receptor to distinct intr...

The maturation of T cells requires signaling from both cytokine and T-cell receptors to gene targets in chromatin, but how chromatin architecture influences this process is largely unknown. Here we show that thymocyte maturation post-positive selection is dependent on the nucleosome remodeling factor (NURF). Depletion of Bptf (bromodomain PHD finger transcription factor), the largest NURF subun...

Monosodium glutamate (MSG), the sodium salt of glutamate, is commonly used as a flavor enhancer in modern nutrition. Recent studies have shown the existence of glutamate receptors on lymphocytes, thymocytes and thymic stromal cells. In this study, we evaluated the in vitro effect of different MSG concentrations on rat thymocyte apoptosis and expression of two apoptosis-related proteins, Bcl-2 a...

Cyclin-dependent kinase-6 (CDK6) is required for early thymocyte development and tumorigenesis. To mechanistically dissect the role of CDK6 in thymocyte development, we generated and analyzed mutant knock-in mice and found that mice expressing a kinase-dead Cdk6 allele (Cdk6(K43M)) had a pronounced reduction in thymocytes and hematopoietic stem cells and progenitor cells (Lin⁻Sca-1⁺c-Kit⁺ [LSK]...

Expression of a novel thymocyte differentiation antigen, JL1, defined by a monoclonal antibody (mAb) developed against human thymocytes showed a specificity for stage II double positive (CD4+CD8+) human cortical thymocytes. This antigen was not expressed at detectable levels on medullary thymocytes, mature peripheral leukocytes, bone marrow cells or on other types of tissues elsewhere in the hu...

A role of beta 2 integrins and one of their ligands, ICAM-1, in thymic macrophage (TMF)/thymocyte interactions was studied. TMF were isolated as adherent cells from 4-day old culture of thymic-cell suspensions either from normal or hydrocortisone-treated rats. Adherent cells were 94-98% positive with ED1 (a pan-macrophage marker). The majority of them (75-95%) expressed the CD11b and CD18 molec...

Wnt signaling has been reported to regulate thymocyte proliferation and selection at several stages during T cell ontogeny, as well as the expression of FoxN1 in thymic epithelial cells (TECs). Kremen1 (Krm1) is a negative regulator of the canonical Wnt signaling pathway, and functions together with the secreted Wnt inhibitor Dickkopf (Dkk) by competing for the lipoprotein receptor-related prot...