Project description:IL-17-producing gd T (Tgd17) cells are early mediators of immunity and autoimmunity that undergo effector programming in the thymus. While Vg subset-restricted regulators of Tgd17 specialization are known, a universal type 17 commitment factor for all gd T cells remains undefined. In this study, we identify the transcription factor c-Maf as an essential and uniform regulator of Tgd17 differentiation and maintenance. The absolute lineage block caused by Maf deficiency reveals a critical effector acquisition checkpoint at the immature CD24+ CD45RBlo gd thymocyte stage. Here, c-Maf enforces Tgd17 identity by promoting chromatin accessibility and activating expression of lineage-defining RORgt and key type 17 program genes, while coordinately antagonizing the negative regulator TCF1, which promotes the alternative IFNg+ Tgd1 fate. During specialization, c-Maf expression is tuned by gdTCR signal strength, implicating c-Maf as a rheostat controlling effector gd T cell generation and connecting gdTCR signals to a core node in the Tgd17 network.
Project description:IL-17-producing gd T (Tgd17) cells are early mediators of immunity and autoimmunity that undergo effector programming in the thymus. While Vg subset-restricted regulators of Tgd17 specialization are known, a universal type 17 commitment factor for all gd T cells remains undefined. In this study, we identify the transcription factor c-Maf as an essential and uniform regulator of Tgd17 differentiation and maintenance. The absolute lineage block caused by Maf deficiency reveals a critical effector acquisition checkpoint at the immature CD24+ CD45RBlo gd thymocyte stage. Here, c-Maf enforces Tgd17 identity by promoting chromatin accessibility and activating expression of lineage-defining RORgt and key type 17 program genes, while coordinately antagonizing the negative regulator TCF1, which promotes the alternative IFNg+ Tgd1 fate. During specialization, c-Maf expression is tuned by gdTCR signal strength, implicating c-Maf as a rheostat controlling effector gd T cell generation and connecting gdTCR signals to a core node in the Tgd17 network.
Project description:Single cell RNA-seq study of T lymphocyte differentiation WT and LAT deficient mice in order to deciphy gd T-cell lineage commitment.
Project description:Single cell RNA-seq study of T lymphocyte differentiation WT and LAT deficient mice in order to deciphy gd T-cell lineage commitment.
Project description:gd T cells are major innate sources of interleukin-17 (IL-17) and interferon-g (IFN-g), which are differentially produced by two thymically-derived subsets segregated on CD27 expression. However, the molecular mechanisms that program the functional differentiation of gd cells remain incompletely understood. Here we show that CD27+ gd cells are epigenetically committed to express Ifng but not Il17, whereas CD27- gd cells spontaneously make IL-17 but can be induced to produce IFN-g under specific inflammatory conditions. This “plastic” behavior of CD27- gd cells associates with permissive histone H3 marks at loci encoding Ifng and upstream “type 1” transcription factors. By contrast, Il17 and related “type 17” factors are epigenetically and transcriptionally active in CD27- but silenced in CD27+ gd cells. Hence, stable versus plastic behaviors of gd cell subsets are controlled by integrated epigenetic and transcriptional mechanisms that regulate the expression of “master” transcription factors and effector cytokine genes.
Project description:gd T cells are major innate sources of interleukin-17 (IL-17) and interferon-g (IFN-g), which are differentially produced by two thymically-derived subsets segregated on CD27 expression. However, the molecular mechanisms that program the functional differentiation of gd cells remain incompletely understood. Here we show that CD27+ gd cells are epigenetically committed to express Ifng but not Il17, whereas CD27- gd cells spontaneously make IL-17 but can be induced to produce IFN-g under specific inflammatory conditions. This M-bM-^@M-^\plasticM-bM-^@M-^] behavior of CD27- gd cells associates with permissive histone H3 marks at loci encoding Ifng and upstream M-bM-^@M-^\type 1M-bM-^@M-^] transcription factors. By contrast, Il17 and related M-bM-^@M-^\type 17M-bM-^@M-^] factors are epigenetically and transcriptionally active in CD27- but silenced in CD27+ gd cells. Hence, stable versus plastic behaviors of gd cell subsets are controlled by integrated epigenetic and transcriptional mechanisms that regulate the expression of M-bM-^@M-^\masterM-bM-^@M-^] transcription factors and effector cytokine genes. ChIP was carried out on FACS-sorted cells from pooled spleen/ lymph nodes. The following antibodies were used: anti-histone H3K4me2 (07-030, Millipore) and anti-histone H3k27me3 (07-449, Millipore). Between 105 - 106 cells were crosslinked with formaldehyde and nuclei were isolated and sonicated with a Sanyo Soniprep 150 at an amplitude of 10 microns with 17 times 10s bursts, resulting in 200M-bM-^@M-^S400bp chromatin fragments. IP was carried out as previously described 49. The Immunoprecipitated DNA released from crosslinked proteins was extracted with the QiaQuick kit (Qiagen) in accordance with the manufacturerM-BM-4s instructions. Deep sequencing was performed at the GeneCore facility of EMBL (http://www.genecore.embl.de/). At least 1 ng of immunoprecipitated DNA was used for library preparation according to the Illumina protocol.