in order to study of genetic variation and identification of yield components in chickpea, a trial consists of 96 accessions of chickpea received from iranian gen bank (seed and plant improvement institute) along with five checks (arman, bivanij, jam, hashem and ilc-482) was conducted based on an augmented design in 2005-06 cropping season at research farm of agricultural college, razi universi...

T-cell receptor (TCR) beta-chain usage and expression of the CD3, CD4, and CD8 differentiation antigens were analyzed in 14 spontaneous AKR lymphomas. Lymphoma cells massively infiltrated and/or proliferated in the organs analyzed (thymus, spleen, and mesenteric lymph nodes), giving rise to a loss of organ structure. One lymphoma occurred only in the thymus, and failed to express CD3, CD4, and ...

Pre-TCR signals regulate the transition of the double-negative (DN) 3 thymocytes to the DN4, and subsequently to the double-positive (DP) stage. In this study, we show that pre-TCR signals activate Akt and that pharmacological inhibition of the PI3K/Akt pathway, or combined ablation of Akt1 and Akt2, and to a lesser extent Akt1 and Akt3, interfere with the differentiation of DN3 and the accumul...

Genetic inactivation of Notch signaling in CD4(-)CD8(-) double-negative (DN) thymocytes was previously shown to impair T cell receptor (TCR) gene rearrangement and to cause a partial block in CD4(+)CD8(+) double-positive (DP) thymocyte development in mice. In contrast, in vitro cultures suggested that Notch was absolutely required for the generation of DP thymocytes independent of pre-TCR expre...

Thymocytes bearing autoreactive TCR are eliminated from the organism by a process termed negative selection. The molecular basis of this deletion has been recently shown to be a consequence of TCR-triggered activation of a caspase by certain peptide-MHC ligands in the immature CD4+CD8+ double-positive (DP) thymocyte subpopulation. Of note, the numerically minor TCRhigh DP thymocyte subpopulatio...

The chemokine CCL25 is constitutively expressed in the thymus, and its receptor CCR9 is expressed on subsets of developing thymocytes. Nevertheless, the function of CCL25/CCR9 in adult thymopoiesis remains unclear. Here, we demonstrate that purified CCR9(-/-) hematopoietic stem cells are deficient in their ability to generate all major thymocyte subsets including double-negative 1 (DN1) cells i...

T cells differentiate from bone marrow-derived stem cells by expressing developmental stage-specific genes. We here searched arrays of genes that are highly expressed in mature CD4-CD8+ (CD8 single-positive (SP)) T cells but little in CD4+CD8+ (double-positive (DP)) cells by cDNA subtraction. Lunatic fringe (Lfng), a modulator of Notch signaling, was identified to be little expressed in DP cell...

We found a population of nonlymphoid cells expressing both CD4 and CD8 in peripheral blood mononuclear cells (PBMCs) of human T-cell leukemia virus type-I pX transgenic rats with autoimmune diseases. These cells, which showed a monocytic phenotype, were also found in wild-type rats, and their number increased by adjuvant-assisted immunization. GM-CSF increased the number of these double-positiv...

As a result of interaction with epithelial cells in the thymic cortex, immature CD4(+)8(+) (double positive, DP) thymocytes express relatively few T cell receptors (TCRs) and contain diminished numbers of coreceptor-associated p56(lck) (lck) PTK molecules. As a result, TCR signal transduction in DP thymocytes is significantly impaired, despite its importance for repertoire selection. We report ...

The CD4(+)CD8(+) (double positive, DP) stage of thymic development is thought to be the earliest period that generates natural Foxp3(+) regulatory T (Treg) cells important for the prevention of autoimmunity. However, we found that most Foxp3(+) DP cells identified by routine flow cytometry represent doublets comprised of Foxp3(-) DP and Foxp3(+) CD4(+)CD8(-) (CD4SP) cells. This was determined u...