Project description:Type-2 innate lymphoid cells (ILC2s) promote anti-helminth responses and contribute to allergies. Though Bcl11b has been previously considered a T-lineage identity transcription factor (TF) that restrains the innate-cell genetic programs, we report here that Bcl11b is highly expressed in mature ILC2s and acts upstream of the key ILC2 TFs Gfi1, Gata-3, and of IL-33 receptor IL1rl1 (T1ST2). Additionally, Bcl11b-/- ILC2s de-repressed Rorγt, Ahr and IL-23 receptor, normally expressed in type-3 ILCs (ILC3s). Consequently, Bcl11b-/- ILC2s lost ILC2 functions and gained ILC3 functions, expanding in response to the protease allergen papain, however producing IL-17 and IL-22, and not IL-5 and IL-13, causing lung neutrophilia rather than eosinophilia, and diminished mucus production. Our results broaden Bcl11b's role from a T-cell only TF, and establishes that Bcl11b sustains mature ILC2 genetic and functional programs and lineage fidelity through positive regulation of essential ILC2 TFs and negative regulation of pivotal ILC3 TFs. RNA-seq analysis on sorted ILC2s from the mLNs of Bcl11bF/F Cre-ERT2 and wildtype mice at steady state following tamoxifen mediated deletion of Bcl11b
Project description:Type-2 innate lymphoid cells (ILC2s) promote anti-helminth responses and contribute to allergies. Though Bcl11b has been previously considered a T-lineage identity transcription factor (TF) that restrains the innate-cell genetic programs, we report here that Bcl11b is highly expressed in mature ILC2s and acts upstream of the key ILC2 TFs Gfi1, Gata-3, and of IL-33 receptor IL1rl1 (T1ST2). Additionally, Bcl11b-/- ILC2s de-repressed Rorγt, Ahr and IL-23 receptor, normally expressed in type-3 ILCs (ILC3s). Consequently, Bcl11b-/- ILC2s lost ILC2 functions and gained ILC3 functions, expanding in response to the protease allergen papain, however producing IL-17 and IL-22, and not IL-5 and IL-13, causing lung neutrophilia rather than eosinophilia, and diminished mucus production. Our results broaden Bcl11b's role from a T-cell only TF, and establishes that Bcl11b sustains mature ILC2 genetic and functional programs and lineage fidelity through positive regulation of essential ILC2 TFs and negative regulation of pivotal ILC3 TFs.
Project description:Innate lymphoid cells (ILCs) have emerged as essential players in the skin-associated immune system in health and inflammatory skin diseases. Their low numbers and lack of specific markers hampered extensive characterization and consequently resulted in limited knowledge of their protein expression. Here, we combined flow cytometry and state-of-the-art proteomics to comprehensively describe the proteins constitutively expressed by ILC2 and ILC3 subsets derived from healthy human skin and peripheral blood. We quantified 6666 proteins from skin ILC and identified 608 differentially expressed proteins in the investigated subsets. In addition to the current analyses, highlighting new functions of ILC, the ILC proteomic libraries and the proteomes of the ILC2 and ILC3 subsets will serve as valuable resources for future analyses of ILC function and are available at http://skin.science.
Project description:Innate lymphoid cell (ILC) subsets that mirror helper T cells in their effector cytokine profiles have recently emerged as central players in both homeostatic and inflammatory conditions. Like their Th1, Th2 and Th17/Th22 helper T cell counterparts, ILC subsets are categorized based on their expression of specific transcription factors and effector cytokines: group 1 ILC (ILC1) express T-bet and IFN-γ; group 2 ILC (ILC2) express GATA-3 and type 2 effector cytokines such as IL-13 and IL-5; and group 3 ILC (ILC3) express RORgt and the cytokines IL-22 and/or IL-17. Under this nomenclature, natural killer (NK) cells and lymphoid tissue inducers (LTi) are considered ILC1 and ILC3, respectively. ILC1 contain both CD4+ and CD4- populations, but whether this phenotypic characteristic reflects functional differences between these two populations is unknown. These studies examine the gene expression profiles of CD4+ vs CD4- ILC1 in a cohort of healthy control subjects. ILC subsets were isolated from the peripheral blood of healthy control subjects. cDNA was isolated and amplified from sorted populations, and gene expression was analyzed by RNAseq
Project description:Innate lymphoid cells (ILCs) are important for mucosal immunity. The intestine harbors all ILC subsets; however, how these cells orchestrate each other to achieve immune homeostasis and mount appropriate immunity during infection remains elusive. Here, we show that the adaptation of the aryl hydrocarbon receptor (Ahr) expression in the gut is a key regulatory mode for the host to keep the ILC balance. Among ILCs, Ahr is most highly expressed by gut ILC2, and controls in a positive feedback manner, chromatin accessibility at the Ahr gene locus. Ahr suppresses Gfi1-mediated ST2 expression in ILC2 and expression of ILC2 effector molecules IL-5, IL-13 and amphiregulin in a cell-intrinsic manner. Ablation of Ahr enhances anti-helminth immunity in the gut, while genetic or pharmacological activation of Ahr suppresses ILC2 but enhances ILC3 to protect the host from Citrobacter rodentium infection. Thus, the host regulates the gut ILC2-ILC3 balance by engaging the Ahr pathway to mount appropriate immunity against various pathogens.
Project description:ILC2 cells are a newly described cell type whose biology and contribution to disease are poorly understood. ILC2 cells are activated by allergens, viral infection, and/or epithelial damage via IL-33 and IL-25. ILC2 cells require IL-2, IL-7, IL-25 and IL-33 for their survival and expansion. In mice, ILC2s produce multiple mediators primarily associated with type 2 inflammation (IL-13, IL-5, IL-4, IL-6, IL-9, IL-10, GM-CSF, amphiregulin). ILC2 cells may contribute to the pathology of asthma through multiple mediators that include IL-13-independent pathways. Our goal is to compare transcriptional profiles of IL-33- or IL-25-activated ILC2 cells from blood to characterize these cells and to identify marker(s) that can be utilized to detect them in human tissue. ILC2 cells (Lineage negative, CRTH2+, CD161+, CD127+) were purified from human blood of 5 different donors by flow cytometry. The ILC2 yield ranged from 20,000 to 165,000 cells per donor (0.001-0.008% WBC). Purified ILC2s were expanded in vitro in the presence of IL-2, IL-7, IL-33 and IL-25 (each at 50 ng/ml) for 7-10 days. Expanded cells maintained the ILC2 phenotype (Lineage negative, CRTH2+, CD161+, CD127+). The cells were rested for 2 days in the presence of 1 ng/ml IL-2 and IL-7 and then treated in the presence of 1 ng/ml IL-2 and IL-7 with either media control, IL-25 (50 ng/ml), IL-33 (50 ng/ml), and/or TSLP (50 ng/ml) in combination, for 6 or 24 hours. Whole RNA was isolated via the RNeasy kit (Qiagen). Stratagene Universal Human Reference RNA was used as the reference.
Project description:GATA3 is indispensable for the development of all IL-7Rα-expressing innate lymphoid cells (ILCs) and maintenance of type 1 ILCs (ILC1s) and type 2 ILCs (ILC2s). However, the importance of low GATA3 expression in type 3 ILCs (ILC3s) is still elusive. Here, we report that GATA3 regulates homeostasis of ILC3s by controlling IL-7Rα expression. In addition, GATA3 is critical for the development of NKp46+ ILC3 subset partially through regulating the balance between T-bet and RORγt. Genome-wide analyses indicate that while GATA3 positively regulates CCR6+ and NKp46+ ILC3 subset-specific genes in respective lineages, it negatively regulates CCR6+ ILC3-specific genes in NKp46+ ILC3s. Furthermore, GATA3 regulates IL-22 production in both CCR6+ and NKp46+ ILC3s. Thus, low GATA3 expression is critical for the development and function of ILC3 subsets. To identify GATA3 regulated genes in total ILC3s with RNA-Seq; To identify unique genes expressed by CCR6+ ILC3 or NKp46+ ILC3 and GATA3 regulated genes within these two ILC3 subsets with RNA-Seq; To identify GATA3 direct binding sites in ILC3s, ILC2s and Th2 cells with ChIP-Seq.
Project description:Group 2 innate lymphoid cells (ILC2s) are linked to type 2 immune diseases but can also molecularly change phenotype and provide type 1 immunity towards pathogens. Here we identify an ILC2 subset which can convert into IL-17 producing NKp44‒ ILC3-like cells. c-Kit and CCR6 define this ILC2 subpopulation which exhibit ILC3 features, including RORγt, which enables the conversion into IL-17 producing cells in response to IL-1β and IL-23. We also report a novel but critical role for TGF-β in promoting the conversion of c-kit‒ ILC2s into RORγt expressing c-Kit+ ILC2s by inducing the upregulation of IL23R, CCR6 and KIT mRNA in these cells. This switch was dependent on RORγt and down-regulation of GATA-3. IL-4 was able to reverse this event supporting a role for this cytokine in maintaining ILC2 identity. Notably, this plasticity has physiological relevance as a subset of RORγt+ ILC2s express the skin homing receptor CCR10 and the frequencies of IL-17‒producing ILC3s are increased at the expense of ILC2s within the lesional skin of psoriatic patients compared to healthy individuals.
Project description:The ETS1 transcription factor is required for the development and cytokine-induced expansion of ILC2 ILC2 cells isolated from ETS1-deleted or litter mate control mice were cultured on OP9-DL1 with IL-7 and IL-33. Subsequently, RNA from ICOS+ cells was extracted, labelled and hybridized to Affymetrix microarrays. The goal of this study is to investigate ETS1-dependent genes in developing ILC2 cells.