Project description:Natural killer (NK) cells belong to the innate immune system where they can control virus infections and developing tumors by cytotoxicity and production of inflammatory cytokines. Most studies of mouse NK cells, however, have focused on conventional NK (cNK) cells found in the spleen. Recently, we described two populations of NK cells within the liver, tissue-resident NK (trNK) cells and those resembling splenic cNK cells. However, the lineage relationship of trNK to cNK cells was unclear because trNK cells display a phenotype associated with immature, developing cNK cells. Moreover, liver trNK cells could be related to thymic NK cells or alternatively, a lineage distinct from both cNK and thymic NK cells. Herein we used detailed transcriptomic, flow cytometric, and functional analysis of mice deficient in several transcription factors to determine that liver trNK cells form a distinct lineage from cNK and thymic NK cells, especially because they do not require NFIL3 (E4BP4), the previously described NK cellspecification factor. Analysis of other tissues indicate the presence of trNK cells in skin and uterus with different transcription factor requirements. Thus, there are at least four distinct lineages of NK cells: cNK, thymic, liver (and skin) trNK, and uterine trNK cells. Liver NK 1.1+CD49+, liver NK 1.1+CD49-, spleen NK 1.1+ CD49- populations of NK cells were sorted with FACS pooling cells from individual mice to end up with ~100k cells for each samples. mRNA was derived from lysates using Invitrogen oligo-dT beads
Project description:Natural killer (NK) cells belong to the innate immune system where they can control virus infections and developing tumors by cytotoxicity and production of inflammatory cytokines. Most studies of mouse NK cells, however, have focused on conventional NK (cNK) cells found in the spleen. Recently, we described two populations of NK cells within the liver, tissue-resident NK (trNK) cells and those resembling splenic cNK cells. However, the lineage relationship of trNK to cNK cells was unclear because trNK cells display a phenotype associated with immature, developing cNK cells. Moreover, liver trNK cells could be related to thymic NK cells or alternatively, a lineage distinct from both cNK and thymic NK cells. Herein we used detailed transcriptomic, flow cytometric, and functional analysis of mice deficient in several transcription factors to determine that liver trNK cells form a distinct lineage from cNK and thymic NK cells, especially because they do not require NFIL3 (E4BP4), the previously described NK cellspecification factor. Analysis of other tissues indicate the presence of trNK cells in skin and uterus with different transcription factor requirements. Thus, there are at least four distinct lineages of NK cells: cNK, thymic, liver (and skin) trNK, and uterine trNK cells. Liver DX5-CD49+, liver DX5+CD49-, spleen DX5+ CD49- populations of NK cells were sorted with FACS pooling cells from individual mice to end up with ~100k cells for each samples. mRNA was derived from lysates using Invitrogen oligo-dT beads
Project description:Natural killer (NK) cells belong to the innate immune system where they can control virus infections and developing tumors by cytotoxicity and production of inflammatory cytokines. Most studies of mouse NK cells, however, have focused on conventional NK (cNK) cells found in the spleen. Recently, we described two populations of NK cells within the liver, tissue-resident NK (trNK) cells and those resembling splenic cNK cells. However, the lineage relationship of trNK to cNK cells was unclear because trNK cells display a phenotype associated with immature, developing cNK cells. Moreover, liver trNK cells could be related to thymic NK cells or alternatively, a lineage distinct from both cNK and thymic NK cells. Herein we used detailed transcriptomic, flow cytometric, and functional analysis of mice deficient in several transcription factors to determine that liver trNK cells form a distinct lineage from cNK and thymic NK cells, especially because they do not require NFIL3 (E4BP4), the previously described NK cellspecification factor. Analysis of other tissues indicate the presence of trNK cells in skin and uterus with different transcription factor requirements. Thus, there are at least four distinct lineages of NK cells: cNK, thymic, liver (and skin) trNK, and uterine trNK cells.
Project description:Natural killer (NK) cells belong to the innate immune system where they can control virus infections and developing tumors by cytotoxicity and production of inflammatory cytokines. Most studies of mouse NK cells, however, have focused on conventional NK (cNK) cells found in the spleen. Recently, we described two populations of NK cells within the liver, tissue-resident NK (trNK) cells and those resembling splenic cNK cells. However, the lineage relationship of trNK to cNK cells was unclear because trNK cells display a phenotype associated with immature, developing cNK cells. Moreover, liver trNK cells could be related to thymic NK cells or alternatively, a lineage distinct from both cNK and thymic NK cells. Herein we used detailed transcriptomic, flow cytometric, and functional analysis of mice deficient in several transcription factors to determine that liver trNK cells form a distinct lineage from cNK and thymic NK cells, especially because they do not require NFIL3 (E4BP4), the previously described NK cellspecification factor. Analysis of other tissues indicate the presence of trNK cells in skin and uterus with different transcription factor requirements. Thus, there are at least four distinct lineages of NK cells: cNK, thymic, liver (and skin) trNK, and uterine trNK cells.
Project description:The HMG-box factor Tcf1 is required during T-cell development in the thymus and mediates the nuclear response to Wnt signals. Tcf1-/- mice have previously been characterized and show developmental blocks at the CD4-CD8- double negative (DN) to CD4+CD8+ double positive transition. Due to the blocks in T-cell development, Tcf1-/- mice normally have a very small thymus. Unexpectedly, a large proportion of Tcf1-/- mice spontaneously develop thymic lymphomas with 50% of mice developing a thymic lymphoma/leukemia at the age of 16 wk. These lymphomas are clonal, highly metastatic, and paradoxically show high Wnt signaling when crossed with Wnt reporter mice and have high expression of Wnt target genes Lef1 and Axin2. In wild-type thymocytes, Tcf1 is higher expressed than Lef1, with a predominance of Wnt inhibitory isoforms. Loss of Tcf1 as repressor of Lef1 leads to high Wnt activity and is the initiating event in lymphoma development, which is exacerbated by activating Notch1 mutations. Thus, Notch1 and loss of Tcf1 functionally act as collaborating oncogenic events. Tcf1 deficiency predisposes to the development of thymic lymphomas by ectopic up-regulation of Lef1 due to lack of Tcf1 repressive isoforms and frequently by cooperating activating mutations in Notch1. Tcf1 therefore functions as a T-cell‚Äìspecific tumor suppressor gene, besides its established role as a Wnt responsive transcription factor. Thus, Tcf1 acts as a molecular switch between proliferative and repressive signals during T-lymphocyte development in the thymus. Using the Tcf1-/- DeltaVII/DeltaVII knockout mouse (Verbeek et al. Nature 1995), thymocytes of 17 mice (5 control Tcf+/-, 4 Tcf-/- and 8 Tcf-/- with thymic lymphoma) were homogenized for RNA isolation using Qiagen RNeasy minicolumns. The quantity and quality of total RNA was determined using spectrophotometry (Nanodrop) and an Agilent Bioanalyzer. One ¬µg of RNA was used to generate cRNA using Affymetrix One cycle cDNA synthesis kit (Affymetrix, Santa Clara, CA, USA), after which the samples were biotinylated using an Affymetrix IVT labeling kit (Affymetrix). The samples were hybridized overnight at 42¬?C to GeneChip mouse genome 430 2.0 Arrays (Affymetrix). Washing and staining steps were performed on a Fluidics station 450, and the Genechips were scanned using a GeneChip scanner 3000 (Affymetrix) at the Department of Immunology, Erasmus Medical Center. Raw data were normalized and summarized using Robust Multichip Average (RMA) method. The experiment consists of 5 control Tcf+/- thymi, 4 Tcf-/- thymi and 8 Tcf-/- thymus samples with thymic lymphoma.
Project description:TCF-1 is an HMG family transcription factor which is known to be critical for T cell development. We discovered that it has a unique role in suppressing malignant transformation of developing thymocytes at early stages. We identified ID2 and LEF-1 as key TCF-1 target genens in tumor suppression. We used microarrays to detect gene expression changes in WT and TCF-1 deficient DN3 thymocytes as well as T cell lymphoma cells developed in TCF-1 KO mice. DN3 thymocytes were directly sorted from WT or TCF-1 KO mice. T cell lymphoma blast cells were also sorted from TCF-1 KO mice that developed the disease. RNA was extracted and hybridized to GeneChip Mouse GENE 1.0 ST arrays (Affymetrix).
Project description:In development, pioneer transcription factors access silent chromatin to reveal lineage-specific gene programs. The structured DNA-binding domains of pioneer factors have been well characterized, but whether and how low-complexity intrinsically disordered regions (IDRs) affect chromatin and control cell fate is unclear. Here, we report deletion of an IDR of the pioneer factor TCF-1, termed “L1”, leads to an early developmental block in T cells. The few T cells that develop from progenitors expressing TCF-1 lacking L1 exhibit lineage infidelity distinct from the lineage diversion of TCF-1 deficient cells. Mechanistically, L1 is required for activation of T cell genes and de-repression of GATA2 driven genes, normally reserved to the mast cell and dendritic cell lineages. Underlying this lineage diversion, L1 mediates binding of TCF-1 to its earliest target genes which are subject to repression as T cells develop. These data suggest TCF-1’s intrinsically disordered N-terminus maintains T cell lineage fidelity.