scholarly journals Role of B Cells in Vaccine-Induced Immunity against Coccidioidomycosis

2005 ◽  
Vol 73 (10) ◽  
pp. 7011-7013 ◽  
Author(s):  
D. Mitchell Magee ◽  
Rhonda L. Friedberg ◽  
Melanie D. Woitaske ◽  
Stephen Albert Johnston ◽  
Rebecca A. Cox
Keyword(s):  
Gene Expression ◽  
B Cells ◽  
B Cell ◽  
Protective Immunity ◽  
Gene Expression Microarrays ◽  
Expression Microarrays ◽  
Induced Immunity

ABSTRACT We investigated secondary immunity against coccidioidomycosis by using gene expression microarrays. Surprisingly, a high percentage of B-cell-related genes were associated with protective immunity. A functional confirmation of the importance of B cells against coccidioidomycosis was achieved by demonstrating that vaccination was not fully protective in B-cell-deficient MuMT mice.

Defining The Role Of Microrna-146a In B Cell Lymphomagenesis

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3805-3805
Author(s):  
Jorge Contreras ◽  
Jayanth Kumar Palanichamy ◽  
Tiffany Tran ◽  
Dinesh S. Rao
Keyword(s):  
Gene Expression ◽  
B Cells ◽  
B Cell ◽  
Conflicts Of Interest ◽  
Cell Lymphoma ◽  
Expression Patterns ◽  
Significant Proportion ◽  
B Cell Lymphoma ◽  
Gene Expression Patterns

Abstract Diffuse large B cell lymphoma (DLBCL) is one of the most common Non-Hodgkin lymphomas among adults. It is a heterogeneous disease characterized by multiple mutations and translocations. Gene expression profiling studies have revealed several characteristic gene expression patterns, with two main patterns emerging, namely Germinal Center(GC) type, and Activated B Cell (ABC) type. ABC-type DLBCL shows gene expression patterns that resemble activated B-cells, with increased expression of anti-apoptotic, and pro-proliferative genes. Critically, upregulation of the NF-κB the pathway is a hallmark of ABC-type DLBCL and has been shown to be necessary for survival, and is caused by several different mutations at different levels within the pathway. Recent work has revealed the critical importance of a new class of small RNA molecules, namely microRNAs, in gene regulation. Of these, microRNA-146a (miR-146a) was discovered as an NF-κB induced microRNA that plays a role as a negative feedback regulator of this pathway by targeting adaptor proteins. To further characterize miR-146a, mice deficient for this miRNA were created, and were found to develop lymphadenopathy, splenomegaly, and myeloid proliferation. As expected, immune cells in these mice have an upregulated NF-κB pathway and many of the phenotypes can be ameliorated by inhibition of the NF-κB pathway. Importantly, a significant proportion of the animals develop B-cell lymphoma at older ages. In this study, we examined the role of miR-146a in the development of malignancy in B-cells. To accelerate the role of miR-146a in tumor formation we overlaid the miR-146a deficient allele onto the Eμ-Myc like mouse model. Eμ-Myc mice develop tumors on average by 14weeks of age. The transgenic status of animals was verified by genotyping, RNA and protein expression analyses. miR-146a sufficient and deficient animals on the Eμ-Myc background were followed for tumor latency by peripheral blood analysis and careful physical examination. Based on approved humane criteria for animal discomfort, animals were sacrificed and hematopoietic tissue was harvested for analysis. Mice deficient for miR-146a had a statistically reduced survival in comparison with miR-146a sufficient animals with a p-value of .0098 (Kaplan Meir survival analysis). Complete Blood Count of animals at time of death revealed an increase leukemia presentation in the miR-146a deficient background. FACS analysis of tumor tissue from both groups revealed an increase in the number of IgM positive tumors in the miR-146a-deficient background indicating skewing towards more mature B cell neoplasms when miR-146a is lacking. Lineage analysis of tumors verified them to be of B cell origin although a subset of miR-146a sufficient tumors had higher numbers of infiltrating myeloid cells compared to deficient animals. Furthermore, histologic analysis of hematopoietic organs showed that while infiltration remained similar in kidneys and liver, more spleens in the miR-146a deficient background tended to be less involved. Our extensive histopathologic and immunophenotypic analyses indicate that miR-146a deficiency drives a more aggressive malignant phenotype in the B-cell lineage. In keeping with this, our profiling studies of human DLBCL suggest that a subset of DLBCL show decreased expression of miR-146a. We are currently examining the status of NF-κB in the murine tumors and using high throughput sequencing approaches to delineate gene expression differences between miR-146a sufficient and deficient tumors. We anticipate the discovery of novel gene targets of miR-146a and expect that these studies will lead to improved diagnostic and therapeutic options for patients of B-cell malignancies. Disclosures: No relevant conflicts of interest to declare.

NFAT2 Is a Critical Regulator Of Anergy Induction In CLL

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 869-869
Author(s):  
Melanie Märklin ◽  
Jonas S. Heitmann ◽  
B. Sc. ◽  
David Worbs ◽  
B. Sc. ◽  
...  
Keyword(s):  
Gene Expression ◽  
B Cells ◽  
Transgenic Mice ◽  
B Cell ◽  
Gene Expression Analysis ◽  
Target Genes ◽  
Flow Cytometric Analysis ◽  
Knock Out ◽  
Flow Cytometric

Abstract NFAT is a family of highly phosphorylated proteins residing in the cytoplasm of resting cells. Upon dephosphorylation by calcineurin, NFAT proteins translocate to the nucleus where they orchestrate developmental and activation programs in diverse cell types. CLL is a clonal disorder of mature B cells characterized by the expression of CD19, CD23 and CD5. With respect to prognosis, it constitutes a heterogeneous disease with some patients exhibiting an indolent course for many years and others progressing rapidly and requiring early treatment. Expression of CD38 and ZAP70 define a subgroup of patients with enhanced responsiveness to stimulation of the B cell receptor (BCR) complex and more aggessive disease. In contrast, another subset of CLL patients with more indolent course is characterized by an anergic B cell phenotype refering to B cell unresponsiveness to IgM ligation and essential lack of phosphotyrosine induction and calcium flux. Here, we analyzed the role of NFAT2 in the pathogenesis of B-CLL and in anergy induction in CLL cells. For this purpose, we generated mice with a conditional NFAT2 knock out allele (NFAT2fl/fl). In order to achieve NFAT2 deletion limited to the B cell lineage, we bred NFAT2fl/fl mice to CD19-Cre mice. To investigate the role of NFAT2 in the pathogenesis of CLL we made use of the Eµ-TCL1 transgenic mouse model in which the TCL1 oncogene is expressed under the control of the Eµ enhancer. TCL1 transgenic mice develop a human-like CLL at the age of approximately 14 wks to which the animals eventually succumb at an average age of 10 months. To analyze the role of NFAT2 in CLL, we generated mice (n=10) whose B cells exhibited a specific deletion of this transcription factor in addition to their transgenic expression of the TCL1 oncogene (TCL1 CD19-Cre NFAT2fl/fl). TCL1 transgenic mice without an NFAT2 deletion served as controls (n=10). To identify novel NFAT2 target genes in CLL cells, we performed a comparative gene expression analysis on CLL cells with intact NFAT2 expression and on CLL cells with NFAT2 deletion using affymetrix microarrays. Mice with NFAT2 knock out exhibited a significantly more aggressive disease course with accelerated accumulation of CD5+CD19+ CLL cells and a significantly reduced life expectancy (200 vs. 325 days) as compared to control animals. Flow cytometric analysis at distinct time points showed a pronounced infiltration by CD5+ B cells of the peritoneal cavity, spleen, lymph nodes, liver and bone marrow which was significantly stronger in the NFAT2 ko cohort. Most of the CD5+ B cells in TCL1+NFAT2 ko mice showed high expression of ZAP70 and CD38, whereas TCL1 transgenic mice only demonstrated very few CD5+ B cells with concomitant expression of ZAP70 and CD38. To investigate the effects of an NFAT2 ko on proliferation and apoptosis of CD5+CD19+ CLL cells, we performed in vivo BrdU incorporation assays with subsequent flow cytometric analysis. Interestingly, we could show that CLL cells isolated from spleens, bone marrow and peripheral blood from mice with an NFAT ko exhibited significantly higher rates of proliferation than control animals. To identify NFAT2 target genes resonsible for the observed alterations in the disease phenotype, we subsequently peformed a gene expression analysis with CD5+CD19+ CLL cells from TCL1+NFAT2 ko mice with CLL cells from TCL1+ mice serving as controls. Here, we detected a significantly altered expression of 22 genes associated with B cell anergy in the TCL1+NFAT2 ko cohort. The vast majority of these genes was expressed significantly less in the absence of NFAT2 with Lck, Pacsin1, Hspa14 and CD166 constituting the strongest hits with up to 10fold reduced gene expression. Downregulation of the identified target genes was subsequently confirmed using RT-PCR and Western Blotting. In summary, our data provide strong evidence that NFAT2 is a critical regulator of CD38 and ZAP70 expression and substantially controls cell cycle progression in CLL cells. In addition, we could show that NFAT2 controls the expression of several anergy-associated genes and that its absence prevents the acquisition of an anergic phenotype by the CLL cells correlating with a significantly more aggressive course of the disease. Taken together, our data demonstrate that NFAT2 plays an essential role in the pathogenesis of CLL and implicate this transcription factor as a potential target in its treatment. Disclosures: No relevant conflicts of interest to declare.

Deciphering the Role of Locally Disordered DNA Methylation on CLL Development In Vivo

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1737-1737
Author(s):  
Anat Biran ◽  
Helene Kretzmer ◽  
Shanye Yin ◽  
Leah Billington ◽  
Fara Faye Regis ◽  
...  
Keyword(s):  
Gene Expression ◽  
B Cells ◽  
B Cell ◽  
Research Funding ◽  
Marginal Zone ◽  
Marginal Zone B Cells ◽  
Genome Wide ◽  
Follicular B Cells

Large-scale DNA methylation analysis of chronic lymphocytic leukemia (CLL) has identified a pervasive genome-wide level of discordance in local methylation state in leukemic cells compared to normal B cells. This is associated with variation in gene expression, increased clonal evolution and poorer clinical outcomes. We hypothesized that locally disordered methylation could lead to dysregulation of gene expression and hence contribute to cancer development and progression. To test this, we have engineered mouse lines with B-cell restricted homozygous or heterozygous knock-out of Dnmt3a by crossing Dnmt3a-floxed mice with CD19-Cre mice. Dnmt3a is a DNA methyltransferase, catalyzing the addition of a methyl group to CpG sequences in the DNA and thereby regulating gene expression. Although DNMT3A mutations are only rarely identified in CLL, RNA sequencing and protein expression analysis reveal dysregulation of DNMT3A. We confirmed partial or complete reduction in Dnmt3a protein levels in B cells from CD19-Cre;Dnmt3a heterozygous (Dnmt3a-het) and CD19-Cre;Dnmt3a homozygous mice (Dnmt3a-hom), respectively. These mice therefore provide a unique opportunity to study B cell restricted changes in locally discordant methylation over time. We first assessed the impact of Dnmt3a deletion on normal B cell development, prior to CLL development, by characterizing splenic B cell of CD19-Cre (control) or Dnmt3a-hom mice. Flow cytometry data using B220, CD21 and CD23 markers to identify B220+CD23+CD21- follicular B cells and B220+CD23+CD21high marginal zone B cells revealed elevated levels of follicular B cells (83.1% vs 87.6%, p=0.008) and reduced levels of marginal zone B cells (9.6% vs 4.1%, p=0.001) in Dnmt3a-hom mice in comparison to control mice (n=3 mice per group). These results indicate that mice with Dnmt3a deletion present with massive changes in their B cells, even prior to overt CLL development. We next monitored both Dnmt3a-het and Dnmt3a-hom cohorts over time for CLL development. We observed that 100% Dnmt3a-hom mice developed CLL-like disease by 7 months (n=23), characterized by CD5+B220+;Igk+ expression and evident within the blood, bone marrow (BM), spleen and peritoneum, suggesting a fundamental role of altered DNMT3A expression in generation of CLL. In comparison, 75% of Dnmt3a-het mice developed CLL-like disease by 18 months (n=12), with similar expansion of CD5+C220+ expansion in the BM and spleen. By RNA-sequencing analysis of normal splenic B cells from CD19-Cre and Dnmt3a-hom mice (n=3 mice, 10 weeks old), we detected substantial changes in gene expression, including 113 upregulated genes and 39 downregulated (p<0.05, FC>2). To explore the development of locally disordered methylation following transformation, CLL cells from Dnmt3a-hom mice (n=3) were subjected to reduced representation bisulfite sequencing (RRBS), a high-throughput technique to analyze genome wide methylation patterns. We found that murine CLL-like cells display locally disordered methylation, which was detected in all genomic features covered by this assay, indicating that disordered methylation is broadly affecting the murine CLL cells' epigenome. Additionally, we identified a set of differentially methylated regions (DMRs) between B cells from CD19-Cre vs CLL cells from Dnmt3a-hom (n = 2,839 DMRs), with a minimum difference of 0.2 and a minimum of 10 CpGs per DMR. Interestingly, gene ontology analysis demonstrated strong association with genes hypermethylated in TCL1 mouse model, linking this model with alternative murine models for CLL. In conclusion, we have studied B cell specific deletion of Dntm3a and showed the development of CLL in 100% of the case in Dnmt3a-hom mice. Our data suggest a fundamental role for Dnmt3a in CLL development through increased locally disordered methylation and changes in associated transcriptional signatures. This mouse model provides an exciting experimental model to undertake functional in vivo studies in order to elucidate the contribution of epigenetic changes on CLL development. Disclosures Neuberg: Pharmacyclics: Research Funding; Madrigal Pharmaceuticals: Equity Ownership; Celgene: Research Funding. Wu:Neon Therapeutics: Other: Member, Advisory Board; Pharmacyclics: Research Funding.

scholarly journals FcmR Shapes BCR Signaling in IgM-Positive Leukemia

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 2620-2620
Author(s):  
Alexandra da Palma Guerreiro ◽  
Cornelia Dorweiler ◽  
Ismini Halmer ◽  
Olaf Merkel ◽  
Elena Maria Hartmann ◽  
...  
Keyword(s):  
Gene Expression ◽  
B Cells ◽  
B Cell ◽  
Research Funding ◽  
Functional Role ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Malignant Cells ◽  
Support Research

Abstract Background: The Fc receptor for IgM (FcmR/ TOSO) is significantly overexpressed on chronic lymphocytic leukemia (CLL) cells from peripheral blood, but becomes down-regulated in the tumor microenvironment by e.g. CD40:CD40L interaction. Since the functional role of FcmR on lymphomagenesis is still not understood, we developed a conditional knockout mouse with B cell-specific FcmR-depletion. These mice were crossbred with the Eµ-TCL1 murine model, which develops a CLL-like phenotype. Results: The depletion of FcmR/TOSO in TCL1 mice (Eµ-Tcl1tg/wt FcmRfl/fl CD19cre/wt; further on called TCT) revealed a significantly shorter overall survival (296 days; n=40) compared to the TOSO expressing control mice (Eµ-Tcl1tg/wt FcmRwt/wt CD19cre/wt; TC; 344 days; n=106; Log-rank p<0.0001). In addition, these mice show a significantly higher blood leukocyte count and lower platelet and erythrocyte count. Leukocytes could be identified as CLL-characteristic leukemic CD19+/CD5+ B cells. Altogether TCT exhibited a faster progress of disease. Spleen immunohistochemistry revealed the transformation of most TCT (14/17 transformed) into an even more aggressive phenotype with increased splenomegaly and change in tissue and cell morphology compared to TC (9/9 not transformed). While characterizing these cells by flow cytometry, we identified a significantly higher expression of IgM on malignant B cells from TCT in comparison to TC mice. This finding indicates that the BCR itself might have a different contribution to lymphomagenesis in FcmR knock-out settings. Therefore, to validate the functional role of FcmR in the process of lymphomagenesis, we performed transcriptome profiling by RNA-Seq using splenic leukemic cells (CD19+ CD5+) from 36-week old TC (n=4) and TCT (n=4) mice. 2089 genes were found to be significantly modulated in the malignant cells of TCT mice, from which 1221 were downregulated and 868 showed an upregulation (significant change in mean expression; p<0.05). To investigate the role of IgM on TCT mice, purified malignant B cells were incubated for two hours with F(ab')2 goat anti-mouse IgM. Strikingly, TCT mice showed 3941 genes (2054 downregulated, 1887 upregulated) with significant difference in expression compared to TC (p<0.05). The gene expression profiles of the anti-IgM treated mice revealed a stronger regulation of BCR signalling in TCT mice, suggesting that FcmR represents an important factor in these processes. We examined the gene expression profiles, using Ingenuity Pathway Analysis Software. Analysis revealed that the most deregulated functions include interferon-signalling, recruitment of leukocytes, infection of cells and cellular movement. Conclusion: Here we present functional evidence that loss of FcmR results in increased IgM/BCR on the surface of non-switched leukemia. Moreover, malignant cells with loss of FcmR are more susceptible to BCR stimulation and show a signature of signalling pathways, which contribute to inflammation in B cell malignancies. Disclosures Fingerle-Rowson: MorphoSys: Employment. Pallasch:Gilead: Research Funding. Wendtner:Abbvie: Consultancy, Honoraria, Other: travel support, Research Funding; Mundipharma: Consultancy, Honoraria, Research Funding; Gilead: Consultancy, Honoraria, Research Funding; GlaxoSmithKline: Consultancy, Honoraria, Other: travel support, Research Funding; Gilead: Consultancy, Honoraria, Other: travel support, Research Funding; Genetech: Consultancy, Honoraria, Other: travel support, Research Funding; Janssen: Consultancy, Honoraria, Other: travel support, Research Funding; Pharmacyclics: Consultancy, Honoraria, Other: travel support, Research Funding; MorphoSys: Consultancy, Honoraria, Other: travel support, Research Funding; Roche: Consultancy, Honoraria, Other: travel support, Research Funding.

TET2 mutations in Diffuse Large B-Cell Lymphoma: The Role of TET2 in the Regulation of Methylation Patterns at TET2 Target Genes

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1364-1364
Author(s):  
Fazila Asmar ◽  
Jesper Christensen ◽  
Jens V Johansen ◽  
Anders Blåbjerg ◽  
Anja Pedersen ◽  
...  
Keyword(s):  
Gene Expression ◽  
B Cells ◽  
B Cell ◽  
Target Genes ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Allelic Loss ◽  
Global Methylation ◽  
Cd34 Cells

Abstract Abstract 1364 Introduction: Cytosine methylation (mC) is a major DNA modification in higher eukaryotic genomes, which is involved in transcriptional silencing. A large amount of data has shown that patterns of DNA methylation are perturbed in hematological cancers including diffuse large B-cell lymphoma (DLBCL). The discovery that the TET hydroxylases convert mC to hydroxymethylcytosine (hmC) is a major break through for our understanding of how DNA methylation is deregulated. Multiple reports describe TET2 (Ten-Eleven Translocation 2) loss-of-function mutations in myeloid malignancies, and a recent study shows that TET2 inactivation perturbs both myeloid and lymphoid development in the mouse, and identifies TET2 mutations in ∼2% of human B-cell lymphoma (Quivoron et al, Cancer Cell 20, 1–14, 2011). Aims: In the present study our aims are to determine the frequency and clinical impact of TET2 mutations in DLBCL, to identify TET2 target genes in CD34+ cells, normal- and malignant B-cells, and evaluate the role of TET2 mutations on the methylation pattern at TET2 targets genes in normal and malignant hematopoiesis. Methods: DNA was isolated from fresh frozen DLBCL (n=110), normal CD34+ cells and B-cells, and a TET2 mutant DLBCL-cell line. Mutation scanning was performed by denaturing gradient gel electrophoresis (DGGE) and automated sequencing. Global methylation profiling was done by Illumina Infinium microarrays, methylation at individual genes by methylation specific melting curve analysis and pyrosequencing. Global mC and hmC patterns were determined by DNA immunoprecipitation and promoter array analysis in cell lines, B-cells and CD34+ cells. TET2 target genes were identified by ChIP followed by deep sequencing. Gene expression by Nimblegen custom made arrays and RT-qPCR. Results: We identified TET2 mutations in 15% of primary diffuse DLBCL, including missense mutation in the catalytic domain (n=8, 2 of which showed allelic loss), loss-of-function mutations (n=7, one of which showed allelic loss), and missense mutation outside the catalytic domain (n=1 with allelic loss). Somatic origin of these mutations was verified in 11 of the 16 cases where matched normal tissue was available. No difference in overall survival was observed between TET2mut and TET2wt cases (P=0.17). To a large extent, the TET2 targets genes identified by ChIP seq analysis were overlapping in CD34+ cells, normal- and malignant B-cells. Gene ontology analysis showed that TET2 target genes are mainly involved in DNA metabolism and repair, metabolic processes and cell cycle homeostasis. Global methylation in TET2mut and TET2wt cases and gene expression data are being analyzed in DLBCL samples. In addition, the distribution patterns of hmC and mC at TET2 target genes and the relation to gene expression is being analyzed in a TET2 mutant DLBCL cell line, normal B-cells and CD34+ cells. Conclusion and further analyses: Here, we show that TET2 mutations are frequent in DLBCL, and identify the TET2 target genes in CD34+ cells, and in normal and malignant B-cells. The role of TET2 mutations for global methylation and for the methylation patterns at TET2 target genes will be presented at the meeting. By investigating the clinical implications of TET2 mutations we aim to identify DLBCL subsets that may benefit from hypomethylating therapy. Furthermore, the identification of hypermethylated TET2 target genes will hopefully contribute to molecular understanding of how TET2 mutations induces malignant transformation. Disclosures: Christensen: EpiTherapeutics: cofounder of EpiTherapeutics and have shares and warrants in the company. Helin:EpiTherapeutics: cofounder of EpiTherapeutics and have shares and warrants in the company.

scholarly journals NSD2-E1099K Mutation Leads to Glucocorticoid-Resistant B Cell Lymphocytic Leukemia in Mice

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 3-4
Author(s):  
Jianping Li ◽  
Crissandra Piper ◽  
Daphne Dupere-Richer ◽  
Heidi Casellas Roman ◽  
Alok Swaroop ◽  
...  
Keyword(s):  
Gene Expression ◽  
B Cells ◽  
Mouse Model ◽  
B Cell ◽  
Germinal Center ◽  
Cell Development ◽  
B Cell Development ◽  
Lymphocytic Leukemia ◽  
Rna Seq

Background: NSD2 (nuclear receptor binding SET domain protein 2) is a histone methyltransferase specific for dimethylation of histone H3 lysine 36 (H3K36me2), a modification associated with gene activation. In pediatric acute lymphoblastic leukemia (ALL), particularly at relapse, a gain of function mutation (E1099K) of NSD2 is found in 10-15% of cases. The NSD2 mutation is found in addition to fusion proteins such as E2A-PBX and ETV6-RUNX1. The mutation can be subclonal at diagnosis and dominant at relapse, suggesting a link to therapeutic resistance. The NSD2-E1099K mutation affects gene expression through an increase in H3K36me2 and a decrease in H3K27me3. Using CRISPR/Cas9-edited isogenic ALL cell lines, we found that NSD2-E1099K mutation drove oncogenic programming by altering chromatin architecture, gene expression and enhancing cell growth, migration and infiltration to the central neural system (CNS). NSD2 mutation caused resistance of ALL cells to glucocorticoids (GC) by blocking genome wide binding of the glucocorticoid receptor (GR, encoded by NR3C1 gene) preventing GC-mediated induction of pro-apoptotic genes. NR3C1 levels were depressed in NSD2-E1099K cells and GC failed to induce autoactivation of NR3C1. While H3K27me3 was globally decreased by NSD2-E1099K, increased H3K27me3 was noted at the promoter of NR3C1, suggesting a novel role of polycomb repressive complex 2 as a therapeutic target for relapsed ALL with NSD2 mutation. While NSD2 is highly expressed in B cells and NSD2 knockout causes defects in B cell development, how the NSD2 mutation affects B cell development and leukemia occurrence in vivo is uncertain. Aims: To determine the role of NSD2 mutation in the pathogenesis of lymphocytic malignancies and GC resistance in a mouse model. Methods: We generated a conditional NSD2-E1099K knock-in mouse model in which the NSD2-E1099K allele was placed in the Rosa26 locus and expressed in B cells under the control of Cd19-Cre (Cd19+/-NSD2E1099K/WT). The resulting phenotype was characterized through peripheral blood counts, cellular morphology and histology of blood smears, bone marrow (BM), spleen and liver, flow cytometric analysis, germinal center B cells (GCB) immunization, BM transplantation, and hematopoiesis analysis in a CD3-/- background. We further established mouse leukemia cell lines with NSD2 mutation for functional analysis. RNA-Seq, real time PCR, immunoblotting, and apoptosis analysis (Annexin V/PI staining) following GC treatment were performed to demonstrate the effects of NSD2 mutation on histone modifications, transcriptome and GC resistance. Results: The NSD2-E1099K mutation increased H3K36me2 and decreased H3K27me3 in isolated B cells from mouse BM and spleen. Mice were aged and did not develop signs of malignancy and RNA-sequencing showed few differences between B cells with or without the NSD2 mutation. However, after immunizing the mice with sheep red blood cells (SRBC), more GCBs were seen in the spleen of NSD2 mutant mice, suggesting mutant NSD2 stimulated germinal center hyperplasia. Transplantation of BM cells from mice expressing NSD2-E1099K into lethally irradiated recipients lead to an expansion of B cells while myeloid and T cells and life span of the recipients impaired. The NSD2 knock-in mouse model was crossed with Cd3-/- mice to create Cd19+/-Cd3-/-NSD2E1099K/WT mice, which within 2 months of birth developed a disease resembling an immature B lymphocytic leukemia (B220+CD19+IgM+IgD-CD5-) with infiltration of the spleen, liver and CNS and a median survival of 4.8 months. These tumors could be transplanted into immunodeficient mice but not immunocompetent mice. RNA seq analysis of these cells revealed 6,815 genes (3,295 upregulated and 3,520 downregulated) differentially expressed in NSD2 mutant B cells compared to normal B cells. The upregulated genes were related to abnormal immunoglobulin level , B cell activation, T-helper 1 physiology, and decreased B cell apoptosis. Importantly, the NSD2 mutant leukemic cells displayed depressed level of NR3C1 gene expression and GC resistance. Conclusions: The NSD2 mutation alters B cell development, particularly in an immunodeficient background and causes B cells to become resistant to glucocorticoids. The inability of the mutation to generate disease on its own except in an immunodeficient background suggests genes that collaborate with NSD2 in ALL may play a role in immune escape. Disclosures No relevant conflicts of interest to declare.

scholarly journals Integrated analysis using methylation and gene expression microarrays reveals PDE4C as a prognostic biomarker in human glioma

2014 ◽  
Vol 32 (1) ◽  
pp. 250-260 ◽  
Author(s):  
ZHAOSHI BAO ◽  
YING FENG ◽  
HONGJUN WANG ◽  
CHUANBAO ZHANG ◽  
LIHUA SUN ◽  
...  
Keyword(s):  
Gene Expression ◽  
Prognostic Biomarker ◽  
Integrated Analysis ◽  
Human Glioma ◽  
Gene Expression Microarrays ◽  
Expression Microarrays

Bruton's tyrosine kinase inhibition in the treatment of preclinical models and multiple sclerosis

2021 ◽  
Vol 27 ◽  
Author(s):  
Anja Steinmaurer ◽  
Isabella Wimmer ◽  
Thomas Berger ◽  
Paulus Stefan Rommer ◽  
Johann Sellner
Keyword(s):  
Multiple Sclerosis ◽  
B Cells ◽  
Tyrosine Kinase ◽  
B Cell ◽  
Bruton’S Tyrosine Kinase ◽  
Cumulative Number ◽  
Phase 2 ◽  
Bruton's Tyrosine Kinase ◽  
Relapsing Remitting

: Significant progress has been made in understanding the immunopathogenesis of multiple sclerosis (MS) over recent years. Successful clinical trials with CD20-depleting monoclonal antibodies have corroborated the fundamental role of B cells in the pathogenesis of MS and reinforced the notion that cells of the B cell lineage are an attractive treatment target. Therapeutic inhibition of Bruton's tyrosine kinase (BTK), an enzyme involved in B cell and myeloid cell activation and function, is regarded as a next-generation approach that aims to attenuate both errant innate and adaptive immune functions. Moreover, brain-penetrant BTK inhibitors may impact compartmentalized inflammation and neurodegeneration within the central nervous system by targeting brain-resident B cells and microglia, respectively. Preclinical studies in animal models of MS corroborated an impact of BTK inhibition on meningeal inflammation and cortical demyelination. Notably, BTK inhibition attenuated the antigen-presenting capacity of B cells and the generation of encephalitogenic T cells. Evobrutinib, a selective oral BTK inhibitor, has been tested recently in a phase 2 study of patients with relapsing-remitting MS. The study met the primary endpoint of a significantly reduced cumulative number of Gadolinium-enhancing lesions under treatment with evobrutinib compared to placebo treatment. Thus, the results of ongoing phase 2 and 3 studies with evobrutinib, fenobrutinib, and tolebrutinib in relapsing-remitting and progressive MS are eagerly awaited. This review article introduces the physiological role of BTK, summarizes the pre-clinical and trial evidence, and addresses the potential beneficial effects of BTK inhibition in MS.

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