ABSTRACT: “Memory-like T cells” are a subset of thymic cells that acquire effector function through the maturation process rather than interaction with specific antigen. Disruption of genes encoding T cell signaling proteins or transcription factors have provided insights into the differentiation of such cells. We show here that in BALB/c but not C57BL/6 mice, a large portion of thymic CD4-CD8+ T cells exhibit a memory-like phenotype. In BALB/c mice, IL-4 secreted by invariant natural killer T (iNKT) cells is both essential and sufficient for the generation of memory-like T cells. In C57BL/6 mice, iNKT cells are less abundant, producing IL-4 that is insufficient to induce thymic memory-like CD8+ T cells. BALB/c mice deficient in the transcription factor Kruppel-like factor (KLF) 13 have comparable numbers of iNKT cells to C57BL/6 mice and extremely low levels of thymic memory-like CD8+ T cells. This work documents the dramatic impact of a small number of KLF13-dependent iNKT cells. FACS-sorted naive splenic CD8 T cells from wild type and KLF13 ko mice were compared.
Project description:“Memory-like T cells” are a subset of thymic cells that acquire effector function through the maturation process rather than interaction with specific antigen. Disruption of genes encoding T cell signaling proteins or transcription factors have provided insights into the differentiation of such cells. We show here that in BALB/c but not C57BL/6 mice, a large portion of thymic CD4-CD8+ T cells exhibit a memory-like phenotype. In BALB/c mice, IL-4 secreted by invariant natural killer T (iNKT) cells is both essential and sufficient for the generation of memory-like T cells. In C57BL/6 mice, iNKT cells are less abundant, producing IL-4 that is insufficient to induce thymic memory-like CD8+ T cells. BALB/c mice deficient in the transcription factor Kruppel-like factor (KLF) 13 have comparable numbers of iNKT cells to C57BL/6 mice and extremely low levels of thymic memory-like CD8+ T cells. This work documents the dramatic impact of a small number of KLF13-dependent iNKT cells.
Project description:Single-cell RNA-seq analysis of murine thymic iNKT cells from three independent BALB/c mice and three independent Cd80/Cd86 (B7)-deficient mice
Project description:Single-cell TCR-seq analysis of murine thymic iNKT cells from three independent BALB/c mice and three independent Cd80/Cd86 (B7)-deficient mice
Project description:Invariant natural killer T cells (iNKT) expressing the retinoic acid receptor-related orphan receptor γt (RORγt) and producing IL-17 represent a minor subset of CD1d-restricted iNKT cells (iNKT17) in C57BL/6J (B6) mice. We aimed in this study to define the reasons for their low distribution and the sequence of events accompanying their normal thymic development. We found that RORγt+ iNKT cells have higher proliferation potential and a greater propensity to apoptosis than RORγt- iNKT cells. These cells do not likely reside in the thymus indicating that thymus emigration, and higher apoptosis potential, could contribute to RORγt+ iNKT cell reduced thymic distribution. Ontogeny studies suggest that mature HSAlow RORγt+ iNKT cells might develop through developmental stages defined by a differential expression of CCR6 and CD138 during which RORγt expression and IL-17 production capabilities are progressively acquired. Finally, we found that RORγt+ iNKT cells perceive a strong TCR signal that could contribute to their entry into a specific Th17 like developmental program influencing their survival and migration. Overall, our study proposes a hypothetical thymic developmental sequence for iNKT17 cells, which could be of great use to study molecular mechanisms regulating this developmental program.
Project description:Single-cell RNA-seq analysis of murine thymic iNKT cells from two independent C57BL/6 mice and two independent Hivep3-deficient mice
Project description:We identified a novel subset of iNKT cells, C2 iNKT cells, that circulate in the periphery. Correspondingly, we characterized the tissue-resident iNKT cell subset, C1 iNKT cells. We also found the precursor of these two subsets of iNKT cells, C0 iNKT cells in thymus. The development and terminal maturation of C2 iNKT cells completely depended on the thymic epithelial IL-15 niche, whereas C1 iNKT cells were regulated also by local IL-15 niches in peripheral tissues. C2 iNKT cells expressed high levels of genes related to cytotoxicity and exhibited more NK cell-like features. Here we characterized the C2 iNKT cells, C1 iNKT cells, and C0 iNKT cells using RNA-seq. We also performed RNA-seq for CD4+ T cells, CD8+ T cells and NK cells as a comparison. To investigate the effect of CD4, we performed the RNA-seq for the CD4+ and CD4- C2 iNKT cells.
Project description:Protein arginine methylation is a post-translational modification catalyzed by protein arginine methyltransferase (PRMT). To elucidate the role of PRMT5 in T cells, we generated T-cell specific PRMT5-deficient mice (Prmt5 flox/d Cd4-Cre mice) and found a severe loss of thymic iNKT cells as well as a reduced number in peripheral CD4+ and CD8+ T cells. As iNKT cells were significantly decreased in the stage 1, 2 and 3 of developmental stages, RNA-seq was performed using stage 1 iNKT cells of control and PRMT5-deficient mice. This transcriptome analysis will provide mechanistic insight into how PRMT5 contributes to thymic iNKT cell development.
Project description:iNKT cells can be classified based on functional criteria into iNKT1, iNKT2 and iNKT17 cells, respectively. Here, a protocol was applied allowing sorting of living cells from thumus of BALB/c and C57BL/6 mice. The obtained gene expression profiles confirmed already existing information regarding the iNKT subtypes and will therefore provide useful hints for further investigations.
Project description:Invariant Natural Killer T (iNKT) cells are a unique subset of T lymphocytes with a memory like phenotype which express invariant T cell receptor (TCR) chain comprised of a Vα14-Jα18 rearrangement in mice. In the present study, we characterize the transcriptomes of thymic iNKT cells at the single cell level to reveal the underlying metabolic adaptation that exists over the course of iNKT cell development.