Project description:We use single-cell RNA-seq to determine distinct selection phenotypes of 2 rare thymic Treg cell progenitors as well as mature thymic Treg cells
Project description:We analyzed open chromatin regions in thymic Treg cells, their immediate precursors (CD25+ Foxp3-), and mature and semi-mature CD4 single positive cells. We wished to understand which chromatin regions become accessible in response to TCR-stimulation and then Foxp3 expression as Treg cells develop.
Project description:We report the identification of immature thymic CD4(-),CD8(-) double-negative (DN)1e cells with the NKT cell lineage potential. We also analyzed the gene expression profiles of DN1e thymocytes compared with those of mature thymic NKT cell developmental stages termed NKT stage-1, 2, and -3, which are characterized by differential expression levels of NK1.1 and CD44 antigens in C57BL/6 mouse strain. Next generation sequencing of total transcriptomes using total RNA isolated from FACS sorted ex vivo thymic DN1eP (Lin-/CD44+/CD25-/CD24low/CD5+/CD27+/Ly108-/CXCR3+) fraction, and mature thymic alphaGalCer-loaded CD1d dimer+TCRbeta+ NKT cell developmental stage-1 (CD44-/NK1.1-), stage-2 (CD44+/NK1.1-), and stage-3 (CD44+/NK1.1+) cells.
Project description:Gene expression analysis of early thymic progenitors and thymus seeding progenitors Eight distinct populations were analysed, each with between 2 and 6 biological replicates.
Project description:This study set out to assay the (polyA+) transcriptomes of single mature (MHCII high) mouse medullary thymic epithelial cells (mTEC). Following isolation by FACs, the transcriptomes of single mature mTEC was assayed using the Fluidigm C1 microfluidics platform and Illumina RNA-seq.
Project description:We report the identification of immature thymic CD4(-),CD8(-) double-negative (DN)1e cells with the NKT cell lineage potential. We also analyzed the gene expression profiles of DN1e thymocytes compared with those of mature thymic NKT cell developmental stages termed NKT stage-1, 2, and -3, which are characterized by differential expression levels of NK1.1 and CD44 antigens in C57BL/6J mouse strain.
Project description:This study set out to assay the (polyA+) transcriptomes of single mature (MHCII high) mouse medullary thymic epithelial cells (mTEC).
Project description:The mechanism of egress of mature regulatory T cells (Tregs) from the thymus to the periphery remains enigmatic, as does the nature of those factors expressed in the thymic environment. Here, we examined the fate of thymic Tregs in TNFα/RelA double-knockout (TA-KO) mice, because TA-KO mice retain a Treg population in the thymus but have only a small Treg population at the periphery. Transplantation of whole TA-KO thymus to under the kidney capsule of Rag1 null mice failed to induce the production of donor-derived splenic Tregs expressing neuropilin-1 (Nrp1), which was reported to be a marker of naturally occurring Tregs, indicating that TA-KO thymic Tregs either do not leave the thymus or are lost at the periphery. We next transplanted enriched TA-KO thymic Tregs to the peripheries of TA-KO mice and traced mouse survival. Transplantation of TA-KO thymic Tregs rescued the lethality in TA-KO mice, demonstrating that TA-KO thymic Tregs remain functional at the periphery. The TA-KO thymic Treg population had highly demethylated CpG motifs in the foxp3 locus, indicating that the cells were arrested at a late-mature stage. Also, the population included a large subpopulation of Tregs expressing IL-7Rα, which is a possible marker of late-mature Tregs. Finally, TA-KO fetal liver chimeric mice developed an Nrp1+ splenic Treg population from TA-KO cells, suggesting that Treg arrest is caused by a lack of RelA in the thymic environment. Together, these results suggest that egress of mature Tregs from the thymus depends on RelA in the thymic environment. For the isolation of thymic Tregs, CD4+CD8α-CD25hi thymocytes were isolated from five 1.5- to 2-week-old TNFα-KO or TA-KO mice by using a FACSAria cell sorter. For the isolation of thymic stromal cells, 10 thymi from 1.5- to 2-week-old TNFα-KO or TA-KO mice were minced with scissors and treated with RPMI 1640 supplemented with 2% FCS, 0.2 mg/ml collagenase (Roche, Basel, Switzerland), 0.2 mg/ml dispase I (Roche), and 100 U/ml DNase I (Life Technologies) for 30 min with stirring. Digested thymi were centrifuged in a Percoll (GE Healthcare Bio-Sciences, Piscataway, NJ, USA) gradient (density, 1.115, 1.065, and PBS) at 1400g for 30 min. Cells in the upper layer were collected, and the CD45-EpCAM+ (thymic epithelial cells) and CD45+EpCAM- populations (enriched thymic stromal cells containing macrophages or dendritic cells) were sorted.