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: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 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:We find that the expression of GATA3 in skin ILCs is significantly lower than in conventional ILC2s of other tissues, indicating that the regulatory role of GATA3 may be different. Indeed, skin ILCs are still maintained after inducing Gata3 depletion in Gata3fl/flCreERT2 mice, when all ILC2s were gone. In addition, about 70% skin ILCs are found to experience RORγt expression as reflected by RORγt fate-mapping. And, conditional Gata3 depletion in the RORγt fate-mapped skin ILCs does not affect their number as well. Therefore, in contrast to conventional ILC2s, GATA3 is not required for skin ILCs for their maintenance. The RORγt fate-mapped skin ILCs have exhibited ILC3-like features. Single-cell transcriptome analysis further reveals that skin ILCs converge on a Ccr6+ ILC3-like state and an Il1rl1+ ILC2-like state. The regulatory role of GATA3 is crucial in the ILC3-like skin ILCs. It promotes the expression of their featured genes, while suppresses the expression of ILC2-like skin ILC featured genes. These ILC3-like skin ILCs locate in close proximity to hair follicles. During hair follicle recycling they migrate from isthmus to suprabulbar to promote the hair follicle growth. Whereas in absence of Gata3, the ILC3-like skin ILCs exhibit defective migration to the suprabulbar and reduced expression of the featured genes in this process. Together, our study evidence that skin ILCs are alternative to conventional ILC2s. In particular, we shed light on the function of GATA3 in promoting the specific gene expression in ILC3-like skin ILCs and regulating their crucial roles in hair follicle recycling, which will improve our knowledge about the involvement of ILCs in maintaining homeostasis of skin.
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: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:Each senescent FB model exhibited different characteristics. Besides the upregulated expression of natural senescence features, FB-UVB and FB-ATV expressed high levels of senescence-related genes including SASP, and FB-P30 had the greatest similarity with FB-E. However, D-galactose-stimulated FB did not clearly present aging characteristics. It provides references for choosing senescent FB model in studying aging and related skin disease.
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.