Project description:A subgroup of CVID patients presents with gastrointestinal complications (enteropathy), which manifests in the duodenum as celiac like-diese ase. CVID enteropathy patients can present with severe histopathology in form of villous atrophy (CVID VA) or without VA (CVID noVA). RNAseq data from CVID VA and CVID noVA derived duodenal tissues were compared to each other and to healthy controls.
Project description:Based on the findings of increased IEL in duodenal biopsies in CVID, an overlap with celiac disease has been suggested. In the present study, increased IEL, in particular in the pars descendens of the duodenum, was one of the most frequent histopathological finding. We therefore examined the gene expression profile in pars descendens of duodenum in CVID patients with increased IEL (n=13, IEL mean 34 [range 22-56] IEL/100 EC), CVID with normal levels of IEL (n=7), celiac disease (n=10, Marsh grade 3a or above) and healthy controls (n=17) by gene expression microarray GI histopathological findings in 53 CVID patients that underwent upper and lower endoscopic examination were addressed. For the microarray analysis 20 CVID (7 CVID_normal and 13 CVID with incresed IEL), 10 patients with celiac diseases and 17 healthy controls were included.
Project description:Immunotherapy, including immune checkpoint blockade (ICB), has become an effective option for treating patients with cancer, especially those with solid tumors. Recently, T cell-based cellular therapies have extended the scope of immunotherapy to B-cell malignancies. Immunotherapy options for patients with acute myeloid leukemia (AML), however, are limited. To identify new immunotherapy approaches for AML, we performed CRISPR/Cas9 AML T cell co-culture screens. We determined that depletion of the transcription factor IRF2BP2 leads to enhanced T cell killing both in vitro and in vivo. Gene expression profiling and flow cytometry studies confirmed enhanced MHC-I expression upon IRF2BP2 loss. Chromatin binding analysis further revealed a regulatory axis whereby MHC-I expression is repressed by IRF2BP2 through its repression of the interferon alpha pathway. Our studies have identified the inhibition of IRF2BP2 as a potential strategy for enhancing T-cell-based therapies in patients with AML
Project description:How transcription factors (TFs) cooperate within large protein complexes to allow rapid modulation of gene expression during development is still largely unknown. Here we show that the key haematopoietic LIM-domain-binding protein-1 (LDB1) TF complex contains several activator and repressor components that together maintain an erythroid-specific gene expression programme primed for rapid activation until differentiation is induced. A combination of proteomics, functional genomics and in vivo studies presented here identifies known and novel co-repressors, most notably the ETO2 and IRF2BP2 proteins, involved in maintaining this primed state. The ETO2â??IRF2BP2 axis, interacting with the NCOR1/SMRT co-repressor complex, suppresses the expression of the vast majority of archetypical erythroid genes and pathways until its decommissioning at the onset of terminal erythroid differentiation. Our experiments demonstrate that multimeric regulatory complexes feature a dynamic interplay between activating and repressing components that determines lineage-specific gene expression and cellular differentiation. ChIP-Sequencing profiles of the IRF2BP2, GFI1B and LSD1 proteins were generated using mouse erythroleukemia (MEL) cells. RNA-seq experiments of Irf2bp2-WT, Irf2bp2-KD, Eto2-WT, Eto2-KD, Gfi1b-WT, Gfi1b-KD, Lsd1-WT, Lsd1-KD, MEL-non-induced, and MEL-induced stages were performed using standard RNA-seq protocol. Illumina HiSeq 2000 (standard TruSeq RNA sequencing protocol) was used for the sequencing.
Project description:The homeostasis of circulating B cell subsets in the peripheral blood of healthy adults is well regulated, but in disease it can be severely disturbed. Thus, a subgroup of patients with common variable immunodeficiency (CVID) presents with an extraordinary expansion of an unusual B cell population characterized by the low expression of CD21. Since these circulating atypical B cells in the blood of CVID patients could not be assigned to any certain B cell differentiation stage in the periphery, they were designated as CD21low B cells. Although, CD21low B cells are polyclonal and unmutated IgM+IgD+ B cells like naive B cells in the peripheral blood, they reveal several distinct phenotypic and functional features. In order to uncover the the global programme of gene expression underlying these differences and changes in CD21low B cells we have performed microarray hybridization experiments and identified differentially expressed genes which define a distinct gene expression profile in CD21low B cells compared to naive B cells. Leucocytes were separated by Ficoll gradient from peripheral blood of healthy donors (HD) and CVID patients. CD19+CD27-CD38+CD21+ naive B cells of HD as well as naive and CD19hiCD27-CD38lowCD21low (CD21low) B cells of CVID patients were sorted using a MoFlow cell sorter. RNA was extracted from sorted ex vivo B cell subpopulations and hybridized on Affymetrix microarrays. Gene expression profiles were compared between CD21low B cells and naive B cells of CVID patients as well as HD naive B cells.
Project description:Common variable immunodeficiency (CVID) is the most prevalent form of symptomatic primary immunodeficiency in humans. The genetic cause of CVID is still unknown in about 70% of cases. 10% of CVID patients carry heterozygous mutations in the tumor necrosis factor receptor superfamily member 13B gene (TNFRSF13B), encoding TACI. Mutations in TNFRSF13B alone may not be sufficient for the development of CVID, as 1% of the healthy population carry these mutations. The common hypothesis is that TACI mutations are not fully penetrant and additional factors contribute to the development of CVID. To determine these additional factors, we investigated the perturbations of transcription factor (TF) binding and the transcriptome profiles in unstimulated and CD40L/IL21-stimulated naïve B cells from CVID patients harboring the C104R mutation in TNFRSF13B and compared them to their healthy relatives with the same mutation. In addition, the proteome of stimulated naïve B cells was investigated. For functional validation, intracellular protein concentrations were measured by flow cytometry. Our analysis revealed 8% less accessible chromatin in unstimulated naïve B cells and 25 % less accessible chromatin in class-switched memory B cells from affected and unaffected TACI mutation carriers compared to healthy donors. The most enriched TF binding motifs in TACI mutation carriers involved members from the ETS, IRF and NF-B TF families. Validation experiments supported dysregulation of the NF-B and MAPK pathways. In steady state, naïve B cells had increased cell death pathways and reduced cell metabolism pathways; while after stimulation, enhanced immune responses and decreased cell survival was detected. Using a multi-omics approach, our findings provide valuable insights into the impaired biology of naïve B cells from TACI mutation carriers.
Project description:Autoantibody-mediated cytopenias (AICs) regularly occur in profoundly IgG-deficient common variable immunodeficiency (CVID) patients. The isotypes, antigenic targets, and origin(s) of disease-causing autoantibodies in this patient population are unclear. Herein, we report that erythrocytes and platelets from CVID patients with AICs (CVID+AIC) are coated with autoreactive IgM. Glycan array-based analyses of CVID+AIC plasma IgM revealed narrow reactivities to erythrocytic I/i antigens and platelet expressed I/i antigen-related glycans but starkly lower binding to hundreds of other pathogen and tumor-associated carbohydrates. Polyclonal B-cell receptors with corresponding I/i antigen reactivities were highly enriched among CVID+AIC circulating marginal zone (MZ) B cells. Within secondary lymphoid tissues, MZ B cells secreted copious IgM when activated by IL-10 secreting FOXP3-CD25hiTfh cells. In lymph nodes from immunocompetent controls, MZ B cells localized outside of GCs near rare FOXP3-CD25+ cells and plentiful FOXP3+ regulatory T cells. In CVID+AIC lymph nodes, counterpart cells localized to similar anatomic positions but CD25hiTfh cells greatly outnumbered regulatory T cells. In total, our findings indicate glycan-reactive IgM autoantibodies produced outside of GC borders may contribute to the autoimmune pathogenesis of CVID.
Project description:Immunotherapy, including immune checkpoint blockade (ICB), has become an effective option for treating patients with cancer, especially those with solid tumors. Recently, T cell-based cellular therapies have extended the scope of immunotherapy to B-cell malignancies. Immunotherapy options for patients with acute myeloid leukemia (AML), however, are limited. To identify new immunotherapy approaches for AML, we performed CRISPR/Cas9 AML T cell co-culture screens. We determined that depletion of the transcription factor IRF2BP2 leads to enhanced T cell killing both in vitro and in vivo. Gene expression profiling and flow cytometry studies confirmed enhanced MHC-I expression upon IRF2BP2 loss. Chromatin binding analysis further revealed a regulatory axis whereby MHC-I expression is repressed by IRF2BP2 through its repression of the interferon alpha pathway. Our studies have identified the inhibition of IRF2BP2 as a potential strategy for enhancing T-cell-based therapies in patients with AML
Project description:To investigate the transcriptional dfferences during B-cell activation in healthy donors and patients with CVID we sorted naïve B cells from the two groups and activated with full BCR-engagement. We then performed differential expression analysis on the seuqneces and we also investigated what pathway changes that we could detect between healthy donors and CVID patients.
Project description:Knocking down IRF2BP2 led to decreased T-cell acute lymphoblastic leukemia (T-ALL) cell survival and growth both in vitro and in vivo. To explore IRF2BP2-dependent gene regulation, RNA-seq analysis was conducted and the differently expressed genes were revealed in the IRF2BP2-knockdown J.gamma1 cells in comparison to control group. Cleavage Under Targets and Tagmentation (CUT&Tag) showed the co-localization of IRF2BP2 with several master transcription factors on chromatin in J.gamma1 cells.