Project description:Innate lymphoid cells (ILCs) represent innate versions of T helper and cytotoxic T cells that differentiate from committed ILC precursors (ILCP). Still, how ILCP relate to mature tissue-resident ILCs remains unclear. We identify ILCP that are present in the blood and all tested lymphoid and non-lymphoid human tissues. Human ILCP fail to express the signature transcription factors (TF) and cytokine outputs of mature NK cells and ILCs but are epigenetically poised to do so. Human ILCP robustly generate all ILC subsets in vitro and in vivo. While human ILCP express RAR related orphan receptor C (RORC), circulating ILCP can be found in RORC-deficient patients that retain potential for EOMES+ NK cells, T-BET+ ILC1, GATA-3+ ILC2 and for IL-22+ but not for IL-17A+ ILC3. We propose a model of tissue ILC differentiation (‘ILC-poiesis’) whereby diverse ILC subsets are generated in situ from ILCP in response to environmental stressors, inflammation and infection.
Project description:Innate lymphoid cells (ILC) represent innate versions of T helper and cytotoxic T cells that differentiate from committed ILC precursors (ILCP). Still, how ILCP relate to mature tissue-resident ILCs remains unclear. We observed that a population of CD117+ ILC from peripheral blood (PB) of healthy donors does not represent any conical ILC subset, but expressed marker (CD117) commonly expressed by hemato-lymphoid progenitors. We therefore hypothesized PB CD117+ ILC might include uncommitted lymphoid precursors. In order to further understand the identity of PB CD117+ ILC, we profiled the transcriptome of highly purified circulating CD117+ ILC compared to CD34+ HSC, the latter representing immature hematopoietic progenitors with multi-lineage potential. Clear differences in gene expression profiles emerged, with a large cluster of 1540 genes expressed at substantially higher levels in CD117+ ILC. In contrast, CD34+ HSC cells highly expressed genes involved in the broad development of diverse hematopoietic lineages. Compared to HSC, CD117+ ILC express high levels of TF that have been shown to be essential for murine ILC development and we did not detect transcripts characteristic of T and B cells development. Transcriptomic analysis suggested that CD117+ ILC represent lymphoid-biased progenitors carrying a TF expression profile resembling a multi-potent ILC precursor (ILCP).
Project description:Subtypes of innate lymphoid cells (ILC), defined by effector function and transcription factor expression, have recently been identified. In the adult, ILC derive from common lymphoid progenitors in bone marrow, although transcriptional regulation of the developmental pathways involved remains poorly defined. TOX is required for development of lymphoid tissue inducer cells, a type of ILC3 required for lymph node organogenesis, and NK cells, a type of ILC1. We show here that production of multiple ILC lineages requires TOX, as a result of TOX-dependent development of common ILC progenitors. Comparative transcriptome analysis demonstrated failure to induce various aspects of the ILC gene program in the absence of TOX, implicating this nuclear factor as a key early determinant of ILC lineage specification. TOX KO vs. wild tyype
Project description:Here we identify the c-kit+ CILP population which generates all ILC subsets including NK cells, and the CD25- ILC2-restricted Sca-1+ CILP. We mapped the transcriptional changes that occur in ILC progenitor commitment identifying new regulatory factors and provide a map for early ILC differentiation. Finally, we mapped the subsequent transcriptional changes that occur in c-kit+ CILP in absence of Id2 and Tcf7, key regulators downstream of Nfil3.
Project description:The NLRP3 inflammasome, estrogen and antimicrobial peptides have all been emphasised to have a vital role in the protection of the bladder urothelium. However, the interdependence between these protective factors during a bladder infection is currently unknown. Our aim was to investigate the role of NLRP3 in regulation of antimicrobial peptides and estrogen signaling in bladder epithelial cells during a UPEC infection. Human bladder epithelial cells and CRISPR/Cas9 generated NLRP3-deficient cells were stimulated with the UPEC strain CFT073 and estradiol. The gene and protein expression were evaluated with microarray, qRT-PCR, western blot and ELISA. Microarray results showed that the expression of most antimicrobial peptides was reduced in CFT073-infected NLRP3-deficient cells compared to Cas9 control cells. Conditioned medium from NLRP3-deficient cells also lost the ability to suppress CFT073 growth. Moreover, NLRP3-deficient cells had lower basal release of Beta-defensin-1, Beta-defensin-2 and RNase7. The ability of estradiol to induce an increased expression of antimicrobial peptides was also abrogated in NLRP3-deficient cells. The decreased antimicrobial peptide expression might be linked to the observed reduced expression and activity of estradiol receptor beta in NLRP3-deficient cells. This study suggests that NLRP3 may regulate the release and expression of antimicrobial peptides and affect estrogen signaling in bladder epithelial cells.
Project description:Resident macrophages are highly abundant in the bladder, playing key roles in directing immunity to uropathogens. Yet, whether they are heterogeneous, where they come from, and precisely how they respond to infection remain largely unknown. We identified two macrophage subsets in mouse bladders with distinct localization, protein expression, and transcriptomes. Using a model of urinary tract infection, we validated our transcriptomics analyses finding that one macrophage subset phagocytosed more bacteria and polarized to a more anti-inflammatory profile, whereas the other subset died rapidly after infection. After resolution of infection, tissue-resident macrophage subsets were partially replaced by monocyte-derived cells with distinct transcriptional profiles. Elimination of these macrophages led to a type 1 biased immune response to challenge infection. Our study brings considerably more knowledge about the biology of bladder resident macrophages and their response to primary and recurrent infection, which may have broader implications for macrophage subsets in other mucosal tissues.
Project description:Innate lymphoid cells (ILC) are tissue-resident effector cells with important roles in tissue homeostasis, protective immunity and inflammatory disease. Here we investigated the role of the transcription factor Bcl6 in small intestinal innate lymphoid cells. Specifically, we performed single-cell RNA-seq on total small intestine lamina propria ILCs from tamoxifen-treated Id2-CreERT2 ROSA26-tdRFP Bcl6-fl/fl mice and Id2-CreERT2 ROSA26-tdRFP controls.
Project description:The family of innate lymphoid cells (ILC) comprises the well-described conventional cytotoxic natural killer cells (NK cells) that patrol lymphoid and non-lymphoid organs to discriminate and eliminate stressed cells (i.e. infected and tumor cells) as well as other ILC subsets that are mainly located in epithelial tissue. How a tumor influences the phenotype and function of those ILC populations at different stages of carcinogenesis is of growing interest. We performed functional and transcriptomic analyses of purified NKp46+ innate lymphoid cells (ILC) from skins, cutaneous lesions and lymph nodes of mice subjected to chemically-induced skin carcinogenesis. We showed that isolated papilloma-derived NKp46+ ILC showed the most divergent gene expression profile compared to their surrounding skin and tumor counterpart. our study indicates that NKp46+ ILC isolated at pre-cancerous stage were enriched in ILC1 subset with less cytotoxic potential than NKp46+ ILC from tumors. These findings revealed a so far unappreciated behavior of NKp46+ ILC at different stages of skin carcinogenesis.
Project description:Study of host response in mice to uropathogenic E. coli (UPEC) infection and the contribution of deletion of the Cnf and HlyA1 toxins to the host response. Mice were infected with UPEC in the bladder for 24 hrs and RNA was isolated from whole bladder to analyze on Agilent whole mouse 2-channel arrays against normal untreated mouse bladder RNA. Biological replicates were analyzed for each condition. Infection: genotype of E. coli CP9 strain strain_or_line_design