Project description:Rna sequencing of purified human group 3 innate lymphoid cells from non-reactive lymph nodes and spleen, inflamed tonsils and peripheral blood.
Project description:Group 3 innate lymphoid cells (ILC3) are defined by the expression of RORM-NM-3t, which is selectively required for their development. The lineage-specified progenitor cells of human ILC3 and their developmental site after birth remain undefined. Here we identified a novel population of human CD34+ hematopoietic progenitor cells (HPC) expressing RORM-NM-3t and sharing with ILC3 a distinct transcriptional signature. RORM-NM-3t+ CD34+ HPC were located in tonsils and intestinal lamina propria (LP) and selectively differentiated towards ILC3. Conversely, RORM-NM-3t- CD34+ HPC displayed commitment potential for both ILC3 and NK cells and the differentiation fate towards these two cell lineages was determined by cytokine and aryl hydrocarbon receptor (AhR) signaling. Thus, we propose that RORM-NM-3t+ CD34+ cells represent human lineage-specified progenitors of IL-22+ ILC3 and that tonsils as well as intestinal LP might be preferential sites of their differentiation. ILC3, NK cells and the CD34+ HPC subsets were sorted from tonsils of 6 distinct donors to purity above 95%. cRNA of the sorted cell populations was hybridized to an Agilent Whole Human Genome Oligo Microarrays (8x60K v2, Design ID 039494)
Project description:Innate lymphoid cells (ILCs) serve as sentinels in mucosal tissues, sensing release of soluble inflammatory mediators, rapidly communicating danger via cytokine secretion, and functioning as guardians of tissue homeostasis. Although ILCs have been studied extensively in model organisms, little is known about these âfirst respondersâ in humans, especially their lineage and functional kinships to cytokine-secreting T helper cell (Th) counterparts. Here, we report gene regulatory circuitries for four human ILCâTh counterparts derived from mucosal environments, revealing that each ILC subset diverges as a distinct lineage from Th and circulating natural killer cells, but shares circuitry devoted to functional polarization with their Th counterparts. Super-enhancers demarcate cohorts of cell identity genes in each lineage, uncovering new modes of regulation for signature cytokines, novel molecules that likely impart important functions to ILCs, and potential mechanisms for autoimmune disease SNP associations within ILCâTh subsets. Molecular profiling of innate lymphoid and T helper cells subsets purified from tonsils and NK cells purified from peripheral blood using Assay for Transposase-Accessible Chromatin (ATAC) and chromatin immunoprecipitation (H3K4me3 and H3K27ac).
Project description:Group 3 innate lymphoid cells (ILC3) are defined by the expression of RORγt, which is selectively required for their development. The lineage-specified progenitor cells of human ILC3 and their developmental site after birth remain undefined. Here we identified a novel population of human CD34+ hematopoietic progenitor cells (HPC) expressing RORγt and sharing with ILC3 a distinct transcriptional signature. RORγt+ CD34+ HPC were located in tonsils and intestinal lamina propria (LP) and selectively differentiated towards ILC3. Conversely, RORγt- CD34+ HPC displayed commitment potential for both ILC3 and NK cells and the differentiation fate towards these two cell lineages was determined by cytokine and aryl hydrocarbon receptor (AhR) signaling. Thus, we propose that RORγt+ CD34+ cells represent human lineage-specified progenitors of IL-22+ ILC3 and that tonsils as well as intestinal LP might be preferential sites of their differentiation.
Project description:Palatine tonsils are secondary lymphoid organs that are strategically positioned in the oropharynx to secure a first line of defense against oral pathogens. Specialized immune-interacting fibroblasts, generally termed fibroblastic reticular cells (FRC), underpin distinct microenvironments within lymphoid organs to compartmentalize and direct the efficient interaction and activation of immune cells. As a particular anatomical property, palatine tonsils harbor a reticular-shaped lymphoepithelium that generates an antigen sampling zone in the crypts. While the histological ultrastructure and the immune cell composition of human palatine tonsils has been elaborated in detail, the molecular identity of the diverse stromal cell compartments including FRC and the specialized lymphoepithelium remains largely unknown. Here, we have employed single cell transcriptomics and extensive flow cytometric analyses to unveil the molecular identity of tonsillar cells and to disentangle the heterogeneity of fibroblast and epithelial cell subsets in palatine tonsils. Our results reveal a remarkable conservation of stromal cell organization and molecularly-defined subsets in infant and adult human palatine tonsils.
Project description:T follicular helper (Tfh) cells are a subset of CD4+ T helper (Th) cells that migrate into germinal centers and promote B cell maturation into memory B and plasma cells. Tfh cells are necessary for promotion of protective humoral immunity following pathogen challenge, but when aberrantly regulated, drive pathogenic antibody formation in autoimmunity and undergo neoplastic transformation in angioimmunoblastic T-cell lymphoma and other primary cutaneous T-cell lymphomas. Limited information is available on the expression and regulation of genes in human Tfh cells. Using a fluorescence activated cell sorting-based strategy, we obtained primary Tfh and non-Tfh T effector (Teff) cells from tonsils and prepared genome-wide maps of active, intermediate, and poised enhancers determined by ChIP-seq, with parallel transcriptome analyses determined by RNA-seq. Tfh cell enhancers were enriched near genes highly expressed in lymphoid cells or involved in lymphoid cell function, with many mapping to sites previously associated with autoimmune disease in genome-wide association studies. A group of active enhancers unique to Tfh cells associated with differentially expressed genes was identified. Fragments from these regions directed expression in reporter gene assays. These data provide a significant resource for studies of T lymphocyte development and differentiation and normal and perturbed Tfh cell function. Using a fluorescence activated cell sorting-based strategy, we obtained primary Tfh and non-Tfh T effector (Teff) cells from tonsils and prepared genome-wide maps of active, intermediate, and poised enhancers determined by ChIP-seq, with parallel transcriptome analyses determined by RNA-seq.
Project description:Non-hematopoietic lymph node stromal cells (LNSCs) regulate lymphocyte trafficking, survival, and function for key roles in host defense, autoimmunity, alloimmunity, and lymphoproliferative disorders. However, study of LNSCs in human diseases is complicated by a dependence on viable lymphoid tissues, which are most often excised prior to establishment of a specific diagnosis. Here, we demonstrate that cryopreservation can be used to bank lymphoid tissue for the study of LNSCs in human disease. Using human tonsils, lymphoid tissue fragments were cryopreserved for subsequent enzymatic digestion and recovery of viable non-hematopoietic cells. Flow cytometry and single-cell transcriptomics identified comparable proportions of LNSC cell types in fresh and cryopreserved tissue. Moreover, cryopreservation had little effect on transcriptional profiles, which showed significant overlap between tonsils and lymph nodes. The presence and spatial distribution of transcriptionally defined cell types was confirmed by in situ analyses. Our broadly applicable approach promises to greatly enable research into the roles of LNSC in human disease.