1
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Gambino S, Quaglia FM, Galasso M, Cavallini C, Chignola R, Lovato O, Giacobazzi L, Caligola S, Adamo A, Putta S, Aparo A, Ferrarini I, Ugel S, Giugno R, Donadelli M, Dando I, Krampera M, Visco C, Scupoli MT. B-cell receptor signaling activity identifies patients with mantle cell lymphoma at higher risk of progression. Sci Rep 2024; 14:6595. [PMID: 38503806 PMCID: PMC10951201 DOI: 10.1038/s41598-024-55728-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 02/27/2024] [Indexed: 03/21/2024] Open
Abstract
Mantle cell lymphoma (MCL) is an incurable B-cell malignancy characterized by a high clinical variability. Therefore, there is a critical need to define parameters that identify high-risk patients for aggressive disease and therapy resistance. B-cell receptor (BCR) signaling is crucial for MCL initiation and progression and is a target for therapeutic intervention. We interrogated BCR signaling proteins (SYK, LCK, BTK, PLCγ2, p38, AKT, NF-κB p65, and STAT5) in 30 primary MCL samples using phospho-specific flow cytometry. Anti-IgM modulation induced heterogeneous BCR signaling responses among samples allowing the identification of two clusters with differential responses. The cluster with higher response was associated with shorter progression free survival (PFS) and overall survival (OS). Moreover, higher constitutive AKT activity was predictive of inferior response to the Bruton's tyrosine kinase inhibitor (BTKi) ibrutinib. Time-to-event analyses showed that MCL international prognostic index (MIPI) high-risk category and higher STAT5 response were predictors of shorter PFS and OS whilst MIPI high-risk category and high SYK response predicted shorter OS. In conclusion, we identified BCR signaling properties associated with poor clinical outcome and resistance to ibrutinib, thus highlighting the prognostic and predictive significance of BCR activity and advancing our understanding of signaling heterogeneity underlying clinical behavior of MCL.
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Affiliation(s)
- Simona Gambino
- Department of Engineering for Innovation Medicine, Section of Biomedicine, University of Verona, Verona, Italy
| | | | - Marilisa Galasso
- Department of Engineering for Innovation Medicine, Section of Biomedicine, University of Verona, Verona, Italy
| | - Chiara Cavallini
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
| | - Roberto Chignola
- Department of Biotechnology, University of Verona, Verona, Italy
| | - Ornella Lovato
- Research Center LURM (Interdepartmental Laboratory of Medical Research), University of Verona, Verona, Italy
| | - Luca Giacobazzi
- Department of Medicine, Section of Immunology, University of Verona, Verona, Italy
| | | | - Annalisa Adamo
- Department of Medicine, Section of Immunology, University of Verona, Verona, Italy
| | | | - Antonino Aparo
- Research Center LURM (Interdepartmental Laboratory of Medical Research), University of Verona, Verona, Italy
| | - Isacco Ferrarini
- Department of Engineering for Innovation Medicine, Section of Biomedicine, University of Verona, Verona, Italy
- Hematology Unit, Azienda Ospedaliera Universitaria Integrata Verona, Verona, Italy
| | - Stefano Ugel
- Department of Medicine, Section of Immunology, University of Verona, Verona, Italy
| | - Rosalba Giugno
- Department of Computer Science, University of Verona, Verona, Italy
| | - Massimo Donadelli
- Department of Neurosciences, Biomedicine and Movement Sciences, Section of Biochemistry, University of Verona, Verona, Italy
| | - Ilaria Dando
- Department of Neurosciences, Biomedicine and Movement Sciences, Section of Biochemistry, University of Verona, Verona, Italy
| | - Mauro Krampera
- Department of Engineering for Innovation Medicine, Section of Biomedicine, University of Verona, Verona, Italy
- Hematology Unit, Azienda Ospedaliera Universitaria Integrata Verona, Verona, Italy
| | - Carlo Visco
- Department of Engineering for Innovation Medicine, Section of Biomedicine, University of Verona, Verona, Italy.
- Hematology Unit, Azienda Ospedaliera Universitaria Integrata Verona, Verona, Italy.
| | - Maria Teresa Scupoli
- Department of Engineering for Innovation Medicine, Section of Biomedicine, University of Verona, Verona, Italy.
- Research Center LURM (Interdepartmental Laboratory of Medical Research), University of Verona, Verona, Italy.
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2
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Witmond M, Keizer E, Kiffen B, Huck WTS, van Buggenum JAGL. Dynamic hydrogen peroxide levels reveal a rate-dependent sensitivity in B-cell lymphoma signaling. Sci Rep 2024; 14:4265. [PMID: 38383739 PMCID: PMC10882005 DOI: 10.1038/s41598-024-54871-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 02/17/2024] [Indexed: 02/23/2024] Open
Abstract
Although in vivo extracellular microenvironments are dynamic, most in vitro studies are conducted under static conditions. Here, we exposed diffuse large B-cell lymphoma (DLBCL) cells to gradient increases in the concentration of hydrogen peroxide (H2O2), thereby capturing some of the dynamics of the tumour microenvironment. Subsequently, we measured the phosphorylation response of B-cell receptor (BCR) signalling proteins CD79a, SYK and PLCγ2 at a high temporal resolution via single-cell phospho-specific flow cytometry. We demonstrated that the cells respond bimodally to static extracellular H2O2, where the percentage of cells that respond is mainly determined by the concentration. Computational analysis revealed that the bimodality results from a combination of a steep dose-response relationship and cell-to-cell variability in the response threshold. Dynamic gradient inputs of varying durations indicated that the H2O2 concentration is not the only determinant of the signalling response, as cells exposed to more shallow gradients respond at lower H2O2 levels. A minimal model of the proximal BCR network qualitatively reproduced the experimental findings and uncovered a rate-dependent sensitivity to H2O2, where a lower rate of increase correlates to a higher sensitivity. These findings will bring us closer to understanding how cells process information from their complex and dynamic in vivo environments.
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Affiliation(s)
- Melde Witmond
- Institute for Molecules and Materials (IMM), Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Emma Keizer
- Institute for Molecules and Materials (IMM), Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Bas Kiffen
- Institute for Molecules and Materials (IMM), Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Wilhelm T S Huck
- Institute for Molecules and Materials (IMM), Radboud University Nijmegen, Nijmegen, The Netherlands.
| | - Jessie A G L van Buggenum
- Institute for Molecules and Materials (IMM), Radboud University Nijmegen, Nijmegen, The Netherlands.
- Single Cell Discoveries (SCD), Utrecht, The Netherlands.
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3
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Neys SFH, Heutz JW, van Hulst JAC, Vink M, Bergen IM, de Jong PHP, Lubberts E, Hendriks RW, Corneth OBJ. Aberrant B cell receptor signaling in circulating naïve and IgA + memory B cells from newly-diagnosed autoantibody-positive rheumatoid arthritis patients. J Autoimmun 2024; 143:103168. [PMID: 38350168 DOI: 10.1016/j.jaut.2024.103168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 01/08/2024] [Accepted: 01/12/2024] [Indexed: 02/15/2024]
Abstract
OBJECTIVE Altered B cell receptor (BCR) signaling has been implicated in the pathogenesis of rheumatoid arthritis (RA). Here we aimed to identify signaling aberrations in autoantibody-positive and autoantibody-negative RA patients by performing a comprehensive analysis of the BCR signaling cascade in different B cell subsets. METHODS We first optimized phosphoflow cytometry for an in-depth analysis of BCR signaling across immunoglobulin isotypes in healthy donors. Subsequently, we compared BCR signaling in circulating B cell subsets from treatment-naïve, newly-diagnosed autoantibody-positive RA and autoantibody-negative RA patients and healthy controls (HCs). RESULTS We observed subset-specific phosphorylation patterns of the BCR signalosome in circulating B cells from healthy donors. Compared with HCs, autoantibody-positive RA patients displayed enhanced responses to BCR stimulation for multiple signaling proteins, specifically in naïve and IgA+ memory B cells. Whereas in unstimulated healthy donor B cells, the phosphorylation status of individual signaling proteins showed only limited correlation, BCR stimulation enhanced the interconnectivity in phosphorylation within the BCR signalosome. However, this strong interconnectivity within the BCR signalosome in stimulated B cells from HCs was lost in RA, especially in autoantibody-positive RA patients. Finally, we observed strong correlations between SYK and BTK protein expression, and IgA and IgG anti-citrullinated protein antibody concentrations in serum from autoantibody-positive RA patients. CONCLUSION Collectively, the isotype-specific analysis of multiple key components of the BCR signalosome identified aberrant BCR signaling responses in treatment-naïve autoantibody-positive RA patients, particularly in naïve B cells and IgA+ memory B cells. Our findings support differential involvement of dysregulated BCR signaling in the pathogenesis of autoantibody-positive and autoantibody-negative RA.
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Affiliation(s)
- Stefan F H Neys
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Judith W Heutz
- Department of Rheumatology, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | | | - Madelief Vink
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Ingrid M Bergen
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Pascal H P de Jong
- Department of Rheumatology, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Erik Lubberts
- Department of Rheumatology, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Rudi W Hendriks
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Rotterdam, the Netherlands
| | - Odilia B J Corneth
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Rotterdam, the Netherlands.
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4
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Simpson A, Jones SA, Fairfax KA. Intracellular Flow Cytometry ("Phosphoflow") to Assess Signal Transduction in Rare Populations Such As Memory B Cell Subsets and Plasma Cells. Methods Mol Biol 2024; 2826:151-163. [PMID: 39017892 DOI: 10.1007/978-1-0716-3950-4_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
Intracellular flow cytometry is a powerful technique that can be used to interrogate signalling in rare cellular populations. The strengths of the technique are that massively parallel readouts can be gained from thousands of single cells simultaneously, and the assay is fast and relatively straightforward. This plate-based protocol enables different doses and different timepoints of stimulation to be assessed and has been optimized for rare B cell populations. Combining this technique with high-dimensional flow cytometry enables multiple signalling proteins to be measured with high confidence.
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5
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Castleman MJ, Santos AL, Lesteberg KE, Maloney JP, Janssen WJ, Mould KJ, Beckham JD, Pelanda R, Torres RM. Activation and pro-inflammatory cytokine production by unswitched memory B cells during SARS-CoV-2 infection. Front Immunol 2023; 14:1213344. [PMID: 37638016 PMCID: PMC10449608 DOI: 10.3389/fimmu.2023.1213344] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 07/03/2023] [Indexed: 08/29/2023] Open
Abstract
Memory B cells are comprised of unswitched (CD27+IgD+) and switched (CD27+IgD-) subsets. The origin and function of unswitched human memory B cells are debated in the literature, whereas switched memory B cells are primed to respond to recurrent infection. Unswitched memory B cells have been described to be reduced in frequency with severe SARS-CoV2 infection and here we characterize their activation status, BCR functionality, and contribution to virally-induced cytokine production. Analyses of whole blood from healthy individuals, people immunized against SARS-CoV2, and those who have had mild and severe SARS-CoV2 infection, confirm a reduction in the frequency of unswitched memory B cells during severe SARS-CoV2 infection and demonstrate this reduction is associated with increased levels of systemic TNFα. We further document how severe viral infection is associated with an increased frequency of 'IgD+' only memory B cells that correlate with increased IgG autoantibody levels. Unswitched and switched memory B cells from severe SARS-CoV2 infection displayed evidence of heightened activation with a concomitant reduction in the expression of the inhibitory receptor CD72. Functionally, both populations of memory B cells from severe SARS-COV2 infection harbored a signaling-competent BCR that displayed enhanced BCR signaling activity in the unswitched population. Finally, we demonstrate that B cells from mild SARS-CoV2 infection are poised to secrete pro-inflammatory cytokines IL-6 and TNFα. Importantly, unswitched memory B cells were a major producer of IL-6 and switched memory B cells were a major producer of TNFα in response to viral TLR ligands. Together these data indicate that B cells contribute to the inflammatory milieu during viral infection.
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Affiliation(s)
- Moriah J. Castleman
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, United States
| | - Adriana Luna Santos
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, United States
| | - Kelsey E. Lesteberg
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, United States
- Department of Medicine, Division of Infectious Disease, University of Colorado School of Medicine, Aurora, CO, United States
| | - James P. Maloney
- Department of Medicine, Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado School of Medicine, Aurora, CO, United States
| | - William J. Janssen
- Department of Medicine, National Jewish Health, Denver, CO, United States
- Department of Medicine, University of Colorado, Aurora, CO, United States
| | - Kara J. Mould
- Department of Medicine, National Jewish Health, Denver, CO, United States
- Department of Medicine, University of Colorado, Aurora, CO, United States
| | - J. David Beckham
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, United States
- Department of Medicine, Division of Infectious Disease, University of Colorado School of Medicine, Aurora, CO, United States
- Rocky Mountain Regional VA, Medical Center, Aurora, CO, United States
| | - Roberta Pelanda
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, United States
| | - Raul M. Torres
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, United States
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6
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Morris G, Gevezova M, Sarafian V, Maes M. Redox regulation of the immune response. Cell Mol Immunol 2022; 19:1079-1101. [PMID: 36056148 PMCID: PMC9508259 DOI: 10.1038/s41423-022-00902-0] [Citation(s) in RCA: 100] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 06/29/2022] [Indexed: 12/20/2022] Open
Abstract
AbstractThe immune-inflammatory response is associated with increased nitro-oxidative stress. The aim of this mechanistic review is to examine: (a) the role of redox-sensitive transcription factors and enzymes, ROS/RNS production, and the activity of cellular antioxidants in the activation and performance of macrophages, dendritic cells, neutrophils, T-cells, B-cells, and natural killer cells; (b) the involvement of high-density lipoprotein (HDL), apolipoprotein A1 (ApoA1), paraoxonase-1 (PON1), and oxidized phospholipids in regulating the immune response; and (c) the detrimental effects of hypernitrosylation and chronic nitro-oxidative stress on the immune response. The redox changes during immune-inflammatory responses are orchestrated by the actions of nuclear factor-κB, HIF1α, the mechanistic target of rapamycin, the phosphatidylinositol 3-kinase/protein kinase B signaling pathway, mitogen-activated protein kinases, 5' AMP-activated protein kinase, and peroxisome proliferator-activated receptor. The performance and survival of individual immune cells is under redox control and depends on intracellular and extracellular levels of ROS/RNS. They are heavily influenced by cellular antioxidants including the glutathione and thioredoxin systems, nuclear factor erythroid 2-related factor 2, and the HDL/ApoA1/PON1 complex. Chronic nitro-oxidative stress and hypernitrosylation inhibit the activity of those antioxidant systems, the tricarboxylic acid cycle, mitochondrial functions, and the metabolism of immune cells. In conclusion, redox-associated mechanisms modulate metabolic reprogramming of immune cells, macrophage and T helper cell polarization, phagocytosis, production of pro- versus anti-inflammatory cytokines, immune training and tolerance, chemotaxis, pathogen sensing, antiviral and antibacterial effects, Toll-like receptor activity, and endotoxin tolerance.
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7
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Perbellini O, Cavallini C, Chignola R, Galasso M, Scupoli MT. Phospho-Specific Flow Cytometry Reveals Signaling Heterogeneity in T-Cell Acute Lymphoblastic Leukemia Cell Lines. Cells 2022; 11:cells11132072. [PMID: 35805156 PMCID: PMC9266179 DOI: 10.3390/cells11132072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/15/2022] [Accepted: 06/27/2022] [Indexed: 12/10/2022] Open
Abstract
Several signaling pathways are aberrantly activated in T-ALL due to genetic alterations of their components and in response to external microenvironmental cues. To functionally characterize elements of the signaling network in T-ALL, here we analyzed ten signaling proteins that are frequently altered in T-ALL -namely Akt, Erk1/2, JNK, Lck, NF-κB p65, p38, STAT3, STAT5, ZAP70, Rb- in Jurkat, CEM and MOLT4 cell lines, using phospho-specific flow cytometry. Phosphorylation statuses of signaling proteins were measured in the basal condition or under modulation with H2O2, PMA, CXCL12 or IL7. Signaling profiles are characterized by a high variability across the analyzed T-ALL cell lines. Hierarchical clustering analysis documents that higher intrinsic phosphorylation of Erk1/2, Lck, ZAP70, and Akt, together with ZAP70 phosphorylation induced by H2O2, identifies Jurkat cells. In contrast, CEM are characterized by higher intrinsic phosphorylation of JNK and Rb and higher responsiveness of Akt to external stimuli. MOLT4 cells are characterized by higher basal STAT3 phosphorylation. These data document that phospho-specific flow cytometry reveals a high variability in intrinsic as well as modulated signaling networks across different T-ALL cell lines. Characterizing signaling network profiles across individual leukemia could provide the basis to identify molecular targets for personalized T-ALL therapy.
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Affiliation(s)
- Omar Perbellini
- Department of Cell Therapy and Hematology, San Bortolo Hospital, Viale Ferdinando Rodolfi, 37, 36100 Vicenza, Italy;
| | - Chiara Cavallini
- Research Center LURM, Interdepartmental Laboratory of Medical Research, University of Verona, Piazzale L.A. Scuro, 10, 37134 Verona, Italy;
| | - Roberto Chignola
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy;
| | - Marilisa Galasso
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Piazzale L.A. Scuro, 10, 37134 Verona, Italy;
| | - Maria T. Scupoli
- Research Center LURM, Interdepartmental Laboratory of Medical Research, University of Verona, Piazzale L.A. Scuro, 10, 37134 Verona, Italy;
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Piazzale L.A. Scuro, 10, 37134 Verona, Italy;
- Correspondence: ; Tel.: +39-045-8128-425
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8
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Pelanda R, Greaves SA, Alves da Costa T, Cedrone LM, Campbell ML, Torres RM. B-cell intrinsic and extrinsic signals that regulate central tolerance of mouse and human B cells. Immunol Rev 2022; 307:12-26. [PMID: 34997597 PMCID: PMC8986553 DOI: 10.1111/imr.13062] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 12/28/2021] [Indexed: 12/20/2022]
Abstract
The random recombination of immunoglobulin V(D)J gene segments produces unique IgM antibodies that serve as the antigen receptor for each developing B cell. Hence, the newly formed B cell repertoire is comprised of a variety of specificities that display a range of reactivity with self-antigens. Newly generated IgM+ immature B cells that are non-autoreactive or that bind self-antigen with low avidity are licensed to leave the bone marrow with their intact antigen receptor and to travel via the blood to the peripheral lymphoid tissue for further selection and maturation. In contrast, clones with medium to high avidity for self-antigen remain within the marrow and undergo central tolerance, a process that revises their antigen receptor or eliminates the autoreactive B cell altogether. Thus, central B cell tolerance is critical for reducing the autoreactive capacity and avidity for self-antigen of our circulating B cell repertoire. Bone marrow cultures and mouse models have been instrumental for understanding the mechanisms that regulate the selection of bone marrow B cells. Here, we review recent studies that have shed new light on the contribution of the ERK, PI3K, and CXCR4 signaling pathways in the selection of mouse and human immature B cells that either bind or do not bind self-antigen.
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Affiliation(s)
- Roberta Pelanda
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA.,Department of Immunology and Genomic Medicine, National Jewish Health, Denver, Colorado, USA
| | - Sarah A Greaves
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Thiago Alves da Costa
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Lena M Cedrone
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Margaret L Campbell
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Raul M Torres
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA.,Department of Immunology and Genomic Medicine, National Jewish Health, Denver, Colorado, USA
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9
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Heward J, Konali L, D'Avola A, Close K, Yeomans A, Philpott M, Dunford J, Rahim T, Al Seraihi AF, Wang J, Korfi K, Araf S, Iqbal S, Bewicke-Copley F, Kumar E, Barisic D, Calaminici M, Clear A, Gribben J, Johnson P, Neve R, Cutillas P, Okosun J, Oppermann U, Melnick A, Packham G, Fitzgibbon J. KDM5 inhibition offers a novel therapeutic strategy for the treatment of KMT2D mutant lymphomas. Blood 2021; 138:370-381. [PMID: 33786580 PMCID: PMC8351530 DOI: 10.1182/blood.2020008743] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 03/04/2021] [Indexed: 02/07/2023] Open
Abstract
Loss-of-function mutations in KMT2D are a striking feature of germinal center (GC) lymphomas, resulting in decreased histone 3 lysine 4 (H3K4) methylation and altered gene expression. We hypothesized that inhibition of the KDM5 family, which demethylates H3K4me3/me2, would reestablish H3K4 methylation and restore the expression of genes repressed on loss of KMT2D. KDM5 inhibition increased H3K4me3 levels and caused an antiproliferative response in vitro, which was markedly greater in both endogenous and gene-edited KMT2D mutant diffuse large B-cell lymphoma cell lines, whereas tumor growth was inhibited in KMT2D mutant xenografts in vivo. KDM5 inhibition reactivated both KMT2D-dependent and -independent genes, resulting in diminished B-cell signaling and altered expression of B-cell lymphoma 2 (BCL2) family members, including BCL2 itself. KDM5 inhibition may offer an effective therapeutic strategy for ameliorating KMT2D loss-of-function mutations in GC lymphomas.
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Affiliation(s)
- James Heward
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Lola Konali
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Annalisa D'Avola
- Cancer Research UK Centre, Cancer Sciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, United Kingdom
| | - Karina Close
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Alison Yeomans
- Cancer Research UK Centre, Cancer Sciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, United Kingdom
| | - Martin Philpott
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
| | - James Dunford
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
| | - Tahrima Rahim
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Ahad F Al Seraihi
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Jun Wang
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Koorosh Korfi
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Shamzah Araf
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Sameena Iqbal
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Findlay Bewicke-Copley
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Emil Kumar
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Darko Barisic
- Department of Medicine, Weill Cornell Medicine, New York, NY; and
| | - Maria Calaminici
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Andrew Clear
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - John Gribben
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Peter Johnson
- Cancer Research UK Centre, Cancer Sciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, United Kingdom
| | | | - Pedro Cutillas
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Jessica Okosun
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Udo Oppermann
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
| | - Ari Melnick
- Department of Medicine, Weill Cornell Medicine, New York, NY; and
| | - Graham Packham
- Cancer Research UK Centre, Cancer Sciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, United Kingdom
| | - Jude Fitzgibbon
- Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
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10
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Roe CE, Hayes MJ, Barone SM, Irish JM. Training Novices in Generation and Analysis of High-Dimensional Human Cell Phospho-Flow Cytometry Data. ACTA ACUST UNITED AC 2021; 93:e71. [PMID: 32250555 DOI: 10.1002/cpcy.71] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This article presents a single experiment designed to introduce a trainee to multiple advanced bench and analysis techniques, including high-dimensional cytometry, profiling cell signaling networks, functional assays with primary human tissue, and single-cell analysis with machine learning tools. The trainee is expected to have only minimal laboratory experience and is not required to have any prior training in flow cytometry, immunology, or data science. This article aims to introduce the advanced research areas with a design that is robust enough that novice trainees will succeed, flexible enough to allow some project customization, and fundamental enough that the skills and knowledge gained will provide a template for future experiments. For advanced users, the updated phospho-flow protocol and the established controls, best practices, and expected outcomes presented here also provide a framework for adapting these tools in new areas with unexplored biology. © 2020 by John Wiley & Sons, Inc. Basic Protocol: Phospho-protein stimulation and mass cytometry data collection Support Protocol: Analysis of signaling mass cytometry data.
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Affiliation(s)
- Caroline E Roe
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee.,Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Madeline J Hayes
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee.,Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Sierra M Barone
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee.,Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jonathan M Irish
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee.,Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
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11
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Abstract
BACKGROUND Lupus B cells not only produce autoantibodies against nuclear antigens but also provide co-stimulation to T cells. However, there is still a lack of comprehensive understanding of the mechanism underlying lupus B cell hyperactivation. METHODS This study focuses on the detection of B cell activation status, analysis of early BCR signaling response, DNA sequencing, and quantity determination of BCR signaling regulators in murine lupus models. RESULTS Our result showed that there is a B cell hyperactivation with a significant elevation of B cell activation markers, and a BCR signaling hyperactivity with an abnormal increase of phosphorylated BCR signaling molecules and cytoplasmic calcium in the early response to BCR crosslinking in B6.Sle1/2/3 lupus mouse. Whole exome sequencing identified a multiple point mutation in the exon of many BCR signaling regulators in common murine lupus models, MRL/lpr, NZM2410, BXSB, NZB, and NZW strains. cNDA sequencing confirmed FcγR2b, Ly9, Pirb, Siglecg, and CD22 BCR signaling regulator variants in B6.Sle1/2/3 lupus mouse, but surface protein expression of these regulators on B cells showed an abnormal increase. CONCLUSION Our findings support that these BCR signaling regulator variants are potential causative genes of B cell hyperactivation in murine lupus models through their possible functional reduction.
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Affiliation(s)
- J Y Ju
- Department of Immunology, 372527Weifang Medical University, Weifang, China
| | - Z W Xu
- Department of Immunology, 372527Weifang Medical University, Weifang, China
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12
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Abstract
PURPOSE OF REVIEW B cell disorders result in decreased levels or function of immunoglobulins in an individual. Genetic mutations have been reported in a variety of B cell disorders. This review, in follow-up to a previous review, describes some rare B cell disorders as well as their known underlying genetic etiologies. RECENT FINDINGS Genetic studies identify and permit precise classification of an increasing number of B cell disorders, leading to a greater understanding of B cell development and function. The B cell disorders are rare diseases. While clinicians are most familiar with X-linked agammaglobulinemia and so-called common variable immunodeficiency (CVID), there are many causes of hypogammaglobulinemia. Genetic testing provides a specific diagnosis, offers useful information for genetic counseling, and can identify previously unrecognized B cell disorders.
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13
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Homeostasis and regulation of autoreactive B cells. Cell Mol Immunol 2020; 17:561-569. [PMID: 32382130 DOI: 10.1038/s41423-020-0445-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 04/10/2020] [Indexed: 12/15/2022] Open
Abstract
In contrast to the previous belief that autoreactive B cells are eliminated from the normal repertoire of B cells, many autoreactive B cells actually escape clonal deletion and develop into mature B cells. These autoreactive B cells in healthy individuals perform some beneficial functions in the host and are homeostatically regulated by regulatory T and B cells or other mechanisms to prevent autoimmune diseases. Autoreactive B-1 cells constitutively produce polyreactive natural antibodies for tissue homeostasis. Recently, autoreactive follicular B cells were reported to participate actively in the germinal center reaction. Furthermore, the selection and usefulness of autoreactive marginal zone (MZ) B cells found in autoimmune diseases are not well understood, although the repertoire of MZ B-cell receptors (BCRs) is presumed to be biased to detect bacterial antigens. In this review, we discuss the autoreactive B-cell populations among all three major B-cell subsets and their regulation in immune responses and diseases.
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14
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Wang JY, Fan H. Assessing the efficacy of mammalian target of rapamycin inhibitors by phosphorylation of p70S6K in CD4-positive cells of liver transplant patients. Medicine (Baltimore) 2019; 98:e17457. [PMID: 31651849 PMCID: PMC6824824 DOI: 10.1097/md.0000000000017457] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The activity of p70S6 kinase located downstream of the mammalian target of rapamycin (mTOR) pathway is sensitive to mTOR inhibitors. However, the methods of assessing p70S6 kinase activity are still unclear. This study aimed to investigate p70S6 kinase activity in CD4-positive cells of liver transplant patients.Liver transplant patients treated with mTOR inhibitors were recruited from Beijing Chaoyang Hospital between October 2014 and October 2016. The influence of mycophenolic acid (MPA) derivatives and prednisone on p70S6 kinase phosphorylation in CD4-positive cells was examined in liver transplant patients and healthy controls (HCs). The phosphorylation of p70S6K in CD4 + CD25 regulatory T cells (Treg cells) and CD4 + CD25- T effector cells was analyzed by phospho-flow cytometry.The phospho-flow technique detected a significant loss of p70S6 kinase phosphorylation in CD4-positive cells of patients treated with mTOR inhibitors compared with HCs. MPA derivatives and prednisone did not affect p70S6 kinase phosphorylation significantly. No significant difference in p70S6 kinase phosphorylation was observed when the whole blood was stored within 3 hours at room temperature. The phosphorylation of p70S6K was significantly lower in CD4 + CD25 Treg cells than in CD4 + CD25-T effector cells in HCs. After liver transplant patients were treated with mTOR inhibitors, p70S6K phosphorylation was more reduced in CD4 + CD25-T effector cells than in CD4 + CD25 Treg cells.The presence of phosphorylation of p70S6 kinase in CD4-positive cells was reduced in liver transplant patients who were treated by mTOR inhibitors.
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Affiliation(s)
- Jun-Yu Wang
- Doctor of Clinical Medicine, Emergency Department of Beijing Chaoyang Hospital of the Capital Medical University,
| | - Hua Fan
- Hepatobiliary Surgery Department of Beijing Chaoyang Hospital of the Capital Medical University, Beijing, China
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15
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Breda CNDS, Davanzo GG, Basso PJ, Saraiva Câmara NO, Moraes-Vieira PMM. Mitochondria as central hub of the immune system. Redox Biol 2019; 26:101255. [PMID: 31247505 PMCID: PMC6598836 DOI: 10.1016/j.redox.2019.101255] [Citation(s) in RCA: 174] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 06/01/2019] [Accepted: 06/10/2019] [Indexed: 02/08/2023] Open
Abstract
Nearly 130 years after the first insights into the existence of mitochondria, new rolesassociated with these organelles continue to emerge. As essential hubs that dictate cell fate, mitochondria integrate cell physiology, signaling pathways and metabolism. Thus, recent research has focused on understanding how these multifaceted functions can be used to improve inflammatory responses and prevent cellular dysfunction. Here, we describe the role of mitochondria on the development and function of immune cells, highlighting metabolic aspects and pointing out some metabolic- independent features of mitochondria that sustain cell function.
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Affiliation(s)
- Cristiane Naffah de Souza Breda
- Transplantation Immunobiology Lab, Department of Immunology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Gustavo Gastão Davanzo
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, University of Campinas, Campinas, Brazil
| | - Paulo José Basso
- Transplantation Immunobiology Lab, Department of Immunology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Niels Olsen Saraiva Câmara
- Transplantation Immunobiology Lab, Department of Immunology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil.
| | - Pedro Manoel Mendes Moraes-Vieira
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, University of Campinas, Campinas, Brazil.
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16
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Huse K, Wogsland CE, Polikowsky HG, Diggins KE, Smeland EB, Myklebust JH, Irish JM. Human Germinal Center B Cells Differ from Naïve and Memory B Cells in CD40 Expression and CD40L-Induced Signaling Response. Cytometry A 2019; 95:442-449. [PMID: 30838773 DOI: 10.1002/cyto.a.23737] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 11/20/2018] [Accepted: 02/08/2019] [Indexed: 12/21/2022]
Abstract
CD40 expression is required for germinal center (GC) formation and function, but the kinetics and magnitude of signaling following CD40 engagement remain poorly characterized in human B cells undergoing GC reactions. Here, differences in CD40 expression and signaling responses were compared across differentiation stages of mature human tonsillar B cells. A combination of mass cytometry and phospho-specific flow cytometry was used to quantify protein expression and CD40L-induced signaling in primary human naïve, GC, and memory B cells. Protein expression signatures of cell subsets were quantified using viSNE and Marker Enrichment Modeling (MEM). This approach revealed enriched expression of CD40 protein in GC B cells, compared to naïve and memory B cells. Despite this, GC B cells responded to CD40L engagement with lower phosphorylation of NFκB p65 during the first 30 min following CD40L activation. Before CD40L stimulation, GC B cells expressed higher levels of suppressor protein IκBα than naïve and memory B cells. Following CD40 activation, IκBα was rapidly degraded and reached equivalently low levels in naïve, GC, and memory B cells at 30 min following CD40L. Quantifying CD40 signaling responses as a function of bound ligand revealed a correlation between bound CD40L and degree of induced NFκB p65 phosphorylation, whereas comparable IκBα degradation occurred at all measured levels of CD40L binding. These results characterize cell-intrinsic signaling differences that exist in mature human B cells undergoing GC reactions. © 2019 International Society for Advancement of Cytometry.
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Affiliation(s)
- Kanutte Huse
- Department of Cancer Immunology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,K.G. Jebsen Centre for B cell malignancies, University of Oslo, Oslo, Norway
| | - Cara E Wogsland
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Hannah G Polikowsky
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Cell & Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Kirsten E Diggins
- Department of Cell & Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Erlend B Smeland
- Department of Cancer Immunology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,K.G. Jebsen Centre for B cell malignancies, University of Oslo, Oslo, Norway
| | - June H Myklebust
- Department of Cancer Immunology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,K.G. Jebsen Centre for B cell malignancies, University of Oslo, Oslo, Norway
| | - Jonathan M Irish
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Cell & Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee.,Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, Tennessee
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17
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Zwang NA, Ganesh BB, Cardenas KT, Chong AS, Finn PW, Perkins DL. An optimized protocol to quantify signaling in human transitional B cells by phospho flow cytometry. J Immunol Methods 2018; 463:112-121. [PMID: 30321549 DOI: 10.1016/j.jim.2018.10.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 07/10/2018] [Accepted: 10/03/2018] [Indexed: 12/18/2022]
Abstract
BACKGROUND AND PURPOSE Phospho flow cytometry is a powerful technique to analyze signaling in rare cell populations. This technique, however, requires harsh conditions for cell fixation and permeabilization, which can denature surface antigens or antibody-conjugated fluorochromes. These are among several technical limitations which have been a barrier to quantify signaling in unique B cell subsets. One such immature subset, transitional B cells (TrBs), may play a role in suppressing solid organ transplant rejection, graft-versus-host disease, autoimmunity, and even the immune response to malignancy. Here we sought to optimize a protocol for quantification of signaling in human TrBs compared with mature B cell subsets. RESULTS TrBs were defined by surface marker expression as CD19+CD24hiCD38hi. Key parameters optimized included antibody clone selection, sequence of surface epitope labeling in relation to paraformaldehyde-based fixation and methanol-based permeabilization, photomultiplier tube (PMT) voltages, and compensation. Special attention was paid to labeling of CD38 with regard to these parameters, and an optimized protocol enabled reliable identification of TrBs, naïve (CD24+CD38+), early memory (CD24hiCD38-), and late memory (CD24-CD38-) B cells. Phospho flow cytometry enabled simultaneous quantification of phosphorylation among at least three different signaling molecules within the same sample. Among normal donors, transitional B cells exhibited diminished mitogen activated protein kinase/extracellular signal-regulated kinase and Akt phospho signaling upon nonspecific stimulation with phorbol 12-myristate 13-acetateand ionomycin stimulation. CONCLUSIONS We optimized an effective protocol to quantify B cell subset signaling upon stimulation. Such a protocol may ultimately serve as the basis for assessing dysfunctional B cell signaling in disease, predict clinical outcomes, and monitor response to B cell-directed therapies.
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Affiliation(s)
- Nicholas A Zwang
- Division of Nephrology, Department of Medicine, The University of Illinois at Chicago, 820 South Wood Street (MC 793), Chicago, IL 60612, USA.
| | - Balaji B Ganesh
- Flow Cytometry Core, The University of Illinois at Chicago, Medical Science Building, 835 South Wolcott Avenue (E-25C), Chicago, IL 60612, USA
| | - Kim T Cardenas
- BioLegend, 9727 Pacific Heights Blvd, San Diego, CA 92121, USA
| | - Anita S Chong
- Department of Surgery, Section of Transplantation Surgery, The University of Chicago, 5841 South Maryland Avenue (SBRI J547/MC 5026), Chicago, IL 60637, USA
| | - Patricia W Finn
- Department of Medicine, The University of Illinois at Chicago, 840 South Wood Street Suite 1020N (MC 787), Chicago, IL 60612, USA
| | - David L Perkins
- Division of Nephrology, Department of Medicine, The University of Illinois at Chicago, 820 South Wood Street (MC 793), Chicago, IL 60612, USA
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18
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Argyropoulos KV, Palomba ML. First-Generation and Second-Generation Bruton Tyrosine Kinase Inhibitors in Waldenström Macroglobulinemia. Hematol Oncol Clin North Am 2018; 32:853-864. [PMID: 30190023 DOI: 10.1016/j.hoc.2018.05.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Waldenström macroglobulinemia (WM) is an indolent B-cell lymphoma that is heavily dependent on Bruton tyrosine kinase (BTK) hyperactivation. Ibrutinib is a first-generation BTK inhibitor that has shown high activity and durable responses in patients with relapsed/refractory WM. Newer and more selective BTK inhibitors are currently being tested in several clinical trials and are expected to address the toxicity and the acquired resistance observed in patients receiving ibrutinib. Updates on ibrutinib and second-generation BTK inhibitors are summarized in this review.
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Affiliation(s)
- Kimon V Argyropoulos
- Immunology Program, Memorial Sloan Kettering Cancer Center, 408 East 69th Street, New York, NY 10021, USA
| | - M Lia Palomba
- Department of Medicine, Lymphoma Service, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA.
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19
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Correa I, Ilieva KM, Crescioli S, Lombardi S, Figini M, Cheung A, Spicer JF, Tutt ANJ, Nestle FO, Karagiannis P, Lacy KE, Karagiannis SN. Evaluation of Antigen-Conjugated Fluorescent Beads to Identify Antigen-Specific B Cells. Front Immunol 2018; 9:493. [PMID: 29628923 PMCID: PMC5876289 DOI: 10.3389/fimmu.2018.00493] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 02/26/2018] [Indexed: 11/30/2022] Open
Abstract
Selection of single antigen-specific B cells to identify their expressed antibodies is of considerable interest for evaluating human immune responses. Here, we present a method to identify single antibody-expressing cells using antigen-conjugated fluorescent beads. To establish this, we selected Folate Receptor alpha (FRα) as a model antigen and a mouse B cell line, expressing both the soluble and the membrane-bound forms of a human/mouse chimeric antibody (MOv18 IgG1) specific for FRα, as test antibody-expressing cells. Beads were conjugated to FRα using streptavidin/avidin-biotin bridges and used to select single cells expressing the membrane-bound form of anti-FRα. Bead-bound cells were single cell-sorted and processed for single cell RNA retrotranscription and PCR to isolate antibody heavy and light chain variable regions. Variable regions were then cloned and expressed as human IgG1/k antibodies. Like the original clone, engineered antibodies from single cells recognized native FRα. To evaluate whether antigen-coated beads could identify specific antibody-expressing cells in mixed immune cell populations, human peripheral blood mononuclear cells (PBMCs) were spiked with test antibody-expressing cells. Antigen-specific cells could comprise up to 75% of cells selected with antigen-conjugated beads when the frequency of the antigen-positive cells was 1:100 or higher. In PBMC pools, beads conjugated to recombinant antigens FRα and HER2 bound antigen-specific anti-FRα MOv18 and anti-HER2 Trastuzumab antibody-expressing cells, respectively. From melanoma patient-derived B cells selected with melanoma cell line-derived protein-coated fluorescent beads, we generated a monoclonal antibody that recognized melanoma antigen-coated beads. This approach may be further developed to facilitate analysis of B cells and their antibody profiles at the single cell level and to help unravel humoral immune repertoires.
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Affiliation(s)
- Isabel Correa
- St. John's Institute of Dermatology, School of Basic & Medical Biosciences, King's College London, Guy's Hospital, London, United Kingdom.,NIHR Biomedical Research Centre at Guy's and St. Thomas's Hospitals and King's College London, King's College London, London, United Kingdom
| | - Kristina M Ilieva
- St. John's Institute of Dermatology, School of Basic & Medical Biosciences, King's College London, Guy's Hospital, London, United Kingdom.,NIHR Biomedical Research Centre at Guy's and St. Thomas's Hospitals and King's College London, King's College London, London, United Kingdom.,Breast Cancer Now Research Unit, School of Cancer & Pharmaceutical Sciences, King's College London, Guy's Cancer Centre, London, United Kingdom
| | - Silvia Crescioli
- St. John's Institute of Dermatology, School of Basic & Medical Biosciences, King's College London, Guy's Hospital, London, United Kingdom.,NIHR Biomedical Research Centre at Guy's and St. Thomas's Hospitals and King's College London, King's College London, London, United Kingdom
| | - Sara Lombardi
- St. John's Institute of Dermatology, School of Basic & Medical Biosciences, King's College London, Guy's Hospital, London, United Kingdom
| | - Mariangela Figini
- Department of Applied Research and Technology Development, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Anthony Cheung
- St. John's Institute of Dermatology, School of Basic & Medical Biosciences, King's College London, Guy's Hospital, London, United Kingdom.,Breast Cancer Now Research Unit, School of Cancer & Pharmaceutical Sciences, King's College London, Guy's Cancer Centre, London, United Kingdom
| | - James F Spicer
- School of Cancer & Pharmaceutical Sciences, King's College London, Guy's Hospital, London, United Kingdom
| | - Andrew N J Tutt
- Breast Cancer Now Research Unit, School of Cancer & Pharmaceutical Sciences, King's College London, Guy's Cancer Centre, London, United Kingdom.,Breast Cancer Now Toby Robins Research Centre, Institute of Cancer Research, London, United Kingdom
| | - Frank O Nestle
- St. John's Institute of Dermatology, School of Basic & Medical Biosciences, King's College London, Guy's Hospital, London, United Kingdom.,NIHR Biomedical Research Centre at Guy's and St. Thomas's Hospitals and King's College London, King's College London, London, United Kingdom.,Immunology and Inflammation Therapeutic Research Area, Sanofi US, Cambridge, MA, United States
| | - Panagiotis Karagiannis
- St. John's Institute of Dermatology, School of Basic & Medical Biosciences, King's College London, Guy's Hospital, London, United Kingdom.,NIHR Biomedical Research Centre at Guy's and St. Thomas's Hospitals and King's College London, King's College London, London, United Kingdom.,Department of Oncology, Haematology and Stem Cell Transplantation, University Hospital of Hamburg Eppendorf, Hamburg, Germany
| | - Katie E Lacy
- St. John's Institute of Dermatology, School of Basic & Medical Biosciences, King's College London, Guy's Hospital, London, United Kingdom
| | - Sophia N Karagiannis
- St. John's Institute of Dermatology, School of Basic & Medical Biosciences, King's College London, Guy's Hospital, London, United Kingdom.,NIHR Biomedical Research Centre at Guy's and St. Thomas's Hospitals and King's College London, King's College London, London, United Kingdom.,Breast Cancer Now Research Unit, School of Cancer & Pharmaceutical Sciences, King's College London, Guy's Cancer Centre, London, United Kingdom
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20
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Low catalase expression confers redox hypersensitivity and identifies an indolent clinical behavior in CLL. Blood 2018; 131:1942-1954. [PMID: 29467184 DOI: 10.1182/blood-2017-08-800466] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 02/17/2018] [Indexed: 11/20/2022] Open
Abstract
B-cell receptor (BCR) signaling is a key determinant of variable clinical behavior and a target for therapeutic interventions in chronic lymphocytic leukemia (CLL). Endogenously produced H2O2 is thought to fine-tune the BCR signaling by reversibly inhibiting phosphatases. However, little is known about how CLL cells sense and respond to such redox cues and what effect they have on CLL. We characterized the response of BCR signaling proteins to exogenous H2O2 in cells from patients with CLL, using phosphospecific flow cytometry. Exogenous H2O2 in the absence of BCR engagement induced a signaling response of BCR proteins that was higher in CLL with favorable prognostic parameters and an indolent clinical course. We identified low catalase expression as a possible mechanism accounting for redox signaling hypersensitivity. Decreased catalase could cause an escalated accumulation of exogenous H2O2 in leukemic cells with a consequent greater inhibition of phosphatases and an increase of redox signaling sensitivity. Moreover, lower levels of catalase were significantly associated with a slower progression of the disease. In leukemic cells characterized by redox hypersensitivity, we also documented an elevated accumulation of ROS and an increased mitochondrial amount. Taken together, our data identified redox sensitivity and metabolic profiles that are linked to differential clinical behavior in CLL. This study advances our understanding of the redox and signaling heterogeneity of CLL and provides the rationale for the development of therapies targeting redox pathways in CLL.
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21
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Plešingerová H, Janovská P, Mishra A, Smyčková L, Poppová L, Libra A, Plevová K, Ovesná P, Radová L, Doubek M, Pavlová Š, Pospíšilová Š, Bryja V. Expression of COBLL1 encoding novel ROR1 binding partner is robust predictor of survival in chronic lymphocytic leukemia. Haematologica 2017; 103:313-324. [PMID: 29122990 PMCID: PMC5792276 DOI: 10.3324/haematol.2017.178699] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 11/03/2017] [Indexed: 01/12/2023] Open
Abstract
Chronic lymphocytic leukemia is a disease with up-regulated expression of the transmembrane tyrosine-protein kinase ROR1, a member of the Wnt/planar cell polarity pathway. In this study, we identified COBLL1 as a novel interaction partner of ROR1. COBLL1 shows clear bimodal expression with high levels in chronic lymphocytic leukemia patients with mutated IGHV and approximately 30% of chronic lymphocytic leukemia patients with unmutated IGHV. In the remaining 70% of chronic lymphocytic leukemia patients with unmutated IGHV, COBLL1 expression is low. Importantly, chronic lymphocytic leukemia patients with unmutated IGHV and high COBLL1 have an unfavorable disease course with short overall survival and time to second treatment. COBLL1 serves as an independent molecular marker for overall survival in chronic lymphocytic leukemia patients with unmutated IGHV. In addition, chronic lymphocytic leukemia patients with unmutated IGHV and high COBLL1 show impaired motility and chemotaxis towards CCL19 and CXCL12 as well as enhanced B-cell receptor signaling pathway activation demonstrated by increased PLCγ2 and SYK phosphorylation after IgM stimulation. COBLL1 expression also changes during B-cell maturation in non-malignant secondary lymphoid tissue with a higher expression in germinal center B cells than naïve and memory B cells. Our data thus suggest COBLL1 involvement not only in chronic lymphocytic leukemia but also in B-cell development. In summary, we show that expression of COBLL1, encoding novel ROR1-binding partner, defines chronic lymphocytic leukemia subgroups with a distinct response to microenvironmental stimuli, and independently predicts survival of chronic lymphocytic leukemia with unmutated IGHV.
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Affiliation(s)
- Hana Plešingerová
- Center of Molecular Biology and Gene Therapy, Department of Internal Medicine- Hematology and Oncology, University Hospital Brno and Medical Faculty, Masaryk University, Brno, Czech Republic.,Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Pavlína Janovská
- Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic.,Department of Cytokinetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic
| | - Archana Mishra
- Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Lucie Smyčková
- Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Lucie Poppová
- Center of Molecular Biology and Gene Therapy, Department of Internal Medicine- Hematology and Oncology, University Hospital Brno and Medical Faculty, Masaryk University, Brno, Czech Republic.,Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Antonín Libra
- Generi Biotech, s.r.o., Hradec Králové, Brno, Czech Republic
| | - Karla Plevová
- Center of Molecular Biology and Gene Therapy, Department of Internal Medicine- Hematology and Oncology, University Hospital Brno and Medical Faculty, Masaryk University, Brno, Czech Republic.,Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Petra Ovesná
- Institute of Biostatistics and Analyses, Masaryk University, Brno, Czech Republic
| | - Lenka Radová
- Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Michael Doubek
- Center of Molecular Biology and Gene Therapy, Department of Internal Medicine- Hematology and Oncology, University Hospital Brno and Medical Faculty, Masaryk University, Brno, Czech Republic.,Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Šárka Pavlová
- Center of Molecular Biology and Gene Therapy, Department of Internal Medicine- Hematology and Oncology, University Hospital Brno and Medical Faculty, Masaryk University, Brno, Czech Republic.,Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Šárka Pospíšilová
- Center of Molecular Biology and Gene Therapy, Department of Internal Medicine- Hematology and Oncology, University Hospital Brno and Medical Faculty, Masaryk University, Brno, Czech Republic.,Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Vítězslav Bryja
- Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic .,Department of Cytokinetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic
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22
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Mavropoulos A, Varna A, Zafiriou E, Liaskos C, Alexiou I, Roussaki-Schulze A, Vlychou M, Katsiari C, Bogdanos DP, Sakkas LI. IL-10 producing Bregs are impaired in psoriatic arthritis and psoriasis and inversely correlate with IL-17- and IFNγ-producing T cells. Clin Immunol 2017; 184:33-41. [DOI: 10.1016/j.clim.2017.04.010] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 04/27/2017] [Indexed: 12/24/2022]
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23
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Gill R, McCabe MJ, Rosenspire AJ. Low level exposure to inorganic mercury interferes with B cell receptor signaling in transitional type 1 B cells. Toxicol Appl Pharmacol 2017; 330:22-29. [PMID: 28668464 DOI: 10.1016/j.taap.2017.06.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 06/09/2017] [Accepted: 06/27/2017] [Indexed: 01/11/2023]
Abstract
Mercury (Hg) has been implicated as a factor contributing to autoimmune disease in animal models and humans. However the mechanism by which this occurs has remained elusive. Since the discovery of B cells it has been appreciated by immunologists that during the normal course of B cell development, some immature B cells must be generated that produce immunoglobulin reactive to self-antigens (auto-antibodies). However in the course of normal development, the vast majority of immature auto-reactive B cells are prevented from maturing by processes collectively known as tolerance. Autoimmune disease arises when these mechanisms of tolerance are disrupted. In the B cell compartment, it is firmly established that tolerance depends in part upon negative selection of self-reactive immature (transitional type 1) B cells. In these cells negative selection depends upon signals generated by the B Cell Receptor (BCR), in the sense that those T1 B cells who's BCRs most strongly bind to, and so generate the strongest signals to self-antigens are neutralized. In this report we have utilized multicolor phosphoflow cytometry to show that in immature T1 B cells Hg attenuates signal generation by the BCR through mechanisms that may involve Lyn, a key tyrosine kinase in the BCR signal transduction pathway. We suggest that exposure to low, environmentally relevant levels of Hg, disrupts tolerance by interfering with BCR signaling in immature B cells, potentially leading to the appearance of mature auto-reactive B cells which have the ability to contribute to auto-immune disease.
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Affiliation(s)
- R Gill
- Department of Immunology, Microbiology and Biochemistry, Wayne State University, Detroit, MI, United States
| | - M J McCabe
- Department of Environmental Medicine, University of Rochester, Rochester, NY, United States
| | - A J Rosenspire
- Department of Immunology, Microbiology and Biochemistry, Wayne State University, Detroit, MI, United States; Center for Urban Responses to Environmental Stressors (CURES), Wayne State University, Detroit, MI, United States.
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24
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Moyo TK, Wilson CS, Moore DJ, Eischen CM. Myc enhances B-cell receptor signaling in precancerous B cells and confers resistance to Btk inhibition. Oncogene 2017; 36:4653-4661. [PMID: 28368423 PMCID: PMC5552428 DOI: 10.1038/onc.2017.95] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 12/29/2016] [Accepted: 03/06/2017] [Indexed: 12/11/2022]
Abstract
Dysregulation of the oncogenic transcription factor MYC induces B cell transformation and is a driver for B cell non-Hodgkin lymphoma (B-NHL). MYC overexpression in B-NHL is associated with more aggressive phenotypes and poor prognosis. Although genomic studies suggest a link between MYC overexpression and B cell receptor (BCR) signaling molecules in B-NHL, signaling pathways essential to Myc-mediated B-cell transformation have not been fully elucidated. We utilized intracellular phospho-flow cytometry to investigate the relationship between Myc and BCR signaling in pre-malignant B cells. Utilizing the Eμ-myc mouse model, where Myc is overexpressed specifically in B cells, both basal and stimulated BCR signaling were increased in precancerous B lymphocytes from Eμ-myc mice compared to wild-type littermates. B cells overexpressing Myc displayed constitutively higher levels of activated CD79α, Btk, Plcγ2, and Erk1/2. Notably, Myc overexpressing B cells maintained elevated BCR signaling despite treatment with ibrutinib, a Bruton’s tyrosine kinase inhibitor. Furthermore, PI3K/Akt pathway signaling was also increased in Eμ-myc B cells, and this increase was partially suppressed with ibrutinib. Additionally, experiments with Btk-null B cells revealed off-target effects of ibrutinib on BCR signaling. Our data show that in pre-malignant B cells, Myc overexpression is sufficient to activate BCR and PI3K/Akt signaling pathways and further enhances signaling following BCR ligation. Therefore, our results indicate precancerous B cells have already acquired enhanced survival and growth capabilities prior to transformation, and that elevated MYC levels confer resistance to pharmacologic inhibitors of BCR signaling, which has significant implications for B-NHL treatment.
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Affiliation(s)
- T K Moyo
- Department of Medicine, Division of Hematology/Oncology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - C S Wilson
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - D J Moore
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - C M Eischen
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
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25
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Distinct patterns of B-cell receptor signaling in non-Hodgkin lymphomas identified by single-cell profiling. Blood 2016; 129:759-770. [PMID: 28011673 DOI: 10.1182/blood-2016-05-718494] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 12/09/2016] [Indexed: 12/22/2022] Open
Abstract
Kinases downstream of B-cell antigen receptor (BCR) represent attractive targets for therapy in non-Hodgkin lymphoma (NHL). As clinical responses vary, improved knowledge regarding activation and regulation of BCR signaling in individual patients is needed. Here, using phosphospecific flow cytometry to obtain malignant B-cell signaling profiles from 95 patients representing 4 types of NHL revealed a striking contrast between chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL) tumors. Lymphoma cells from diffuse large B-cell lymphoma patients had high basal phosphorylation levels of most measured signaling nodes, whereas follicular lymphoma cells represented the opposite pattern with no or very low basal levels. MCL showed large interpatient variability in basal levels, and elevated levels for the phosphorylated forms of AKT, extracellular signal-regulated kinase, p38, STAT1, and STAT5 were associated with poor outcome. CLL tumors had elevated basal levels for the phosphorylated forms of BCR-signaling nodes (Src family tyrosine kinase, spleen tyrosine kinase [SYK], phospholipase Cγ), but had low α-BCR-induced signaling. This contrasted MCL tumors, where α-BCR-induced signaling was variable, but significantly potentiated as compared with the other types. Overexpression of CD79B, combined with a gating strategy whereby signaling output was directly quantified per cell as a function of CD79B levels, confirmed a direct relationship between surface CD79B, immunoglobulin M (IgM), and IgM-induced signaling levels. Furthermore, α-BCR-induced signaling strength was variable across patient samples and correlated with BCR subunit CD79B expression, but was inversely correlated with susceptibility to Bruton tyrosine kinase (BTK) and SYK inhibitors in MCL. These individual differences in BCR levels and signaling might relate to differences in therapy responses to BCR-pathway inhibitors.
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26
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Gravelle P, Do C, Franchet C, Mueller S, Oberic L, Ysebaert L, Larocca LM, Hohaus S, Calmels MN, Frenois FX, Kridel R, Gascoyne RD, Laurent G, Brousset P, Valitutti S, Laurent C. Impaired functional responses in follicular lymphoma CD8 +TIM-3 + T lymphocytes following TCR engagement. Oncoimmunology 2016; 5:e1224044. [PMID: 27990323 DOI: 10.1080/2162402x.2016.1224044] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 08/03/2016] [Accepted: 08/09/2016] [Indexed: 12/31/2022] Open
Abstract
Upregulation of T cell immunoglobulin-3 (TIM-3) has been associated with negative regulation of the immune response in chronic infection and cancer, including lymphoma. Here, we investigated the possible correlation between TIM-3 expression by ex vivo cytotoxic T cells (CTL) from follicular lymphoma (FL) biopsies and their functional unresponsiveness that could limit the favorable impact of CTL on disease progression. We report a high percentage of CD8+TIM-3+T cells in lymph nodes of FL patients. When compared to their CD8+TIM-3- counterparts, CD8+TIM-3+ T cells exhibited defective cytokine production following TCR engagement. Furthermore, CD8+TIM-3+ T cells display ex vivo markers of lytic granule release and remain unresponsive to further TCR-induced activation of the lytic machinery. Although confocal microscopy showed that TIM-3 expression on CD8+ T cells correlated with minor alterations of immunological synapse, a selective reduction of ERK signaling in CD8+TIM-3+T cells was observed by phospho-flow analysis. Finally, short relapse-free survival despite rituximab(R)-chemotherapy was observed in patients with high content of TIM-3+ cells and a poor infiltrate of granzyme B+ T cells in FL lymph nodes. Together, our data indicate that, besides selective TCR early signaling defects, TIM-3 expression correlates with unresponsiveness of ex vivo CD8+ T cells in FL. They show that scores based on the combination of exhaustion and cytolytic markers in FL microenvironment might be instrumental to identify patients at early risk of relapses following R-chemotherapy.
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Affiliation(s)
- Pauline Gravelle
- Centre de Physiopathologie de Toulouse Purpan, INSERM U1043, Toulouse, France; Département de Pathologie, Institut Universitaire du Cancer-Oncopole de Toulouse, Toulouse, France; Laboratoire d'Excellence "TOUCAN," Toulouse, France; Program Hospitalo-Universitaire en Cancérologie "CAPTOR," Toulouse, France; CALYM Carnot Institute, Pierre-Bénite, France
| | - Catherine Do
- Institute for Cancer Genetics, Columbia University , New York, USA
| | - Camille Franchet
- Centre de Physiopathologie de Toulouse Purpan, INSERM U1043, Toulouse, France; Département de Pathologie, Institut Universitaire du Cancer-Oncopole de Toulouse, Toulouse, France; Université Toulouse III Paul-Sabatier, Toulouse, France
| | - Sabina Mueller
- Centre de Physiopathologie de Toulouse Purpan, INSERM U1043, Toulouse, France; Laboratoire d'Excellence "TOUCAN," Toulouse, France
| | - Lucie Oberic
- Program Hospitalo-Universitaire en Cancérologie "CAPTOR," Toulouse, France; Département d'Hématologie, Institut Universitaire du Cancer-Oncopole de Toulouse, Toulouse, France
| | - Loïc Ysebaert
- Laboratoire d'Excellence "TOUCAN," Toulouse, France; Program Hospitalo-Universitaire en Cancérologie "CAPTOR," Toulouse, France; CALYM Carnot Institute, Pierre-Bénite, France; Université Toulouse III Paul-Sabatier, Toulouse, France; Département d'Hématologie, Institut Universitaire du Cancer-Oncopole de Toulouse, Toulouse, France; Centre de Recherches en Cancérologie de Toulouse, INSERM UMR1037, Toulouse, France
| | - Luigi Maria Larocca
- Istituto di Anatomia Patologica, Università Cattolica del Sacro Cuore , Roma, Italy
| | - Stefan Hohaus
- Istituto di Ematologia, Università Cattolica del Sacro Cuore , Roma, Italy
| | | | - François-Xavier Frenois
- Département de Pathologie, Institut Universitaire du Cancer-Oncopole de Toulouse , Toulouse, France
| | - Robert Kridel
- Center for Lymphoid Cancer, BC Cancer Agency , Vancouver, BC, Canada
| | - Randy D Gascoyne
- Center for Lymphoid Cancer, BC Cancer Agency , Vancouver, BC, Canada
| | - Guy Laurent
- Laboratoire d'Excellence "TOUCAN," Toulouse, France; Program Hospitalo-Universitaire en Cancérologie "CAPTOR," Toulouse, France; CALYM Carnot Institute, Pierre-Bénite, France; Université Toulouse III Paul-Sabatier, Toulouse, France; Département d'Hématologie, Institut Universitaire du Cancer-Oncopole de Toulouse, Toulouse, France; Centre de Recherches en Cancérologie de Toulouse, INSERM UMR1037, Toulouse, France
| | - Pierre Brousset
- Département de Pathologie, Institut Universitaire du Cancer-Oncopole de Toulouse, Toulouse, France; Laboratoire d'Excellence "TOUCAN," Toulouse, France; Program Hospitalo-Universitaire en Cancérologie "CAPTOR," Toulouse, France; CALYM Carnot Institute, Pierre-Bénite, France; Université Toulouse III Paul-Sabatier, Toulouse, France; Centre de Recherches en Cancérologie de Toulouse, INSERM UMR1037, Toulouse, France
| | - Salvatore Valitutti
- Centre de Physiopathologie de Toulouse Purpan, INSERM U1043, Toulouse, France; Département de Pathologie, Institut Universitaire du Cancer-Oncopole de Toulouse, Toulouse, France; Laboratoire d'Excellence "TOUCAN," Toulouse, France; Université Toulouse III Paul-Sabatier, Toulouse, France
| | - Camille Laurent
- Centre de Physiopathologie de Toulouse Purpan, INSERM U1043, Toulouse, France; Département de Pathologie, Institut Universitaire du Cancer-Oncopole de Toulouse, Toulouse, France; Laboratoire d'Excellence "TOUCAN," Toulouse, France; Program Hospitalo-Universitaire en Cancérologie "CAPTOR," Toulouse, France; CALYM Carnot Institute, Pierre-Bénite, France; Université Toulouse III Paul-Sabatier, Toulouse, France; Centre de Recherches en Cancérologie de Toulouse, INSERM UMR1037, Toulouse, France
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27
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Moens L, Kane A, Tangye SG. Naïve and memory B cells exhibit distinct biochemical responses following BCR engagement. Immunol Cell Biol 2016; 94:774-86. [PMID: 27101923 DOI: 10.1038/icb.2016.41] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 04/17/2016] [Accepted: 04/18/2016] [Indexed: 01/08/2023]
Abstract
Immunological memory is characterized by the rapid reactivation of memory B cells that produce large quantities of high-affinity antigen-specific antibodies. This contrasts the response of naïve B cells, and the primary immune response, which is much slower and of lower affinity. Memory responses are critical for protection against infectious diseases and form the basis of most currently available vaccines. Although we have known about the phenomenon of long-lived memory for centuries, the biochemical differences underlying these diverse responses of naïve and memory B cells is incompletely resolved. Here we investigated the nature of B-cell receptor (BCR) signaling in human splenic naïve, IgM(+) memory and isotype-switched memory B cells following multivalent BCR crosslinking. We observed comparable rapid and transient phosphorylation kinetics for proximal (phosphotyrosine and spleen tyrosine kinase) and propagation (B-cell linker, phospholipase Cγ2) signaling components in these different B-cell subsets. However, the magnitude of activation of downstream components of the BCR signaling pathway were greater in memory compared with naïve cells. Although no differences were observed in the magnitude of Ca(2+) mobilization between subsets, IgM(+) memory B cells exhibited a more rapid Ca(2+) mobilization and a greater depletion of the Ca(2+) endoplasmic reticulum stores, while IgG(+) memory B cells had a prolonged Ca(2+) uptake. Collectively, our findings show that intrinsic signaling features of B-cell subsets contribute to the robust response of human memory B cells over naïve B cells. This has implications for our understanding of memory B-cell responses and provides a framework to modulate these responses in the setting of vaccination and immunopathologies, such as immunodeficiency and autoimmunity.
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Affiliation(s)
- Leen Moens
- Immunology Division, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Alisa Kane
- Immunology Division, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,St Vincent's Clinical School, UNSW, Darlinghurst, New South Wales, Australia
| | - Stuart G Tangye
- Immunology Division, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,St Vincent's Clinical School, UNSW, Darlinghurst, New South Wales, Australia
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28
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Dysfunctional BLK in common variable immunodeficiency perturbs B-cell proliferation and ability to elicit antigen-specific CD4+ T-cell help. Oncotarget 2016; 6:10759-71. [PMID: 25926555 PMCID: PMC4484417 DOI: 10.18632/oncotarget.3577] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 02/21/2015] [Indexed: 11/25/2022] Open
Abstract
Common Variable Immunodeficiency (CVID) is the most prevalent primary antibody deficiency, and characterized by defective generation of high-affinity antibodies. Patients have therefore increased risk to recurrent infections of the respiratory and intestinal tract. Development of high-affinity antigen-specific antibodies involves two key actions of B-cell receptors (BCR): transmembrane signaling through BCR-complexes to induce B-cell differentiation and proliferation, and BCR-mediated antigen internalization for class-II MHC-mediated presentation to acquire antigen-specific CD4(+) T-cell help.We identified a variant (L3P) in the B-lymphoid tyrosine kinase (BLK) gene of 2 related CVID-patients, which was absent in healthy relatives. BLK belongs to the Src-kinases family and involved in BCR-signaling. Here, we sought to clarify BLK function in healthy human B-cells and its association to CVID.BLK expression was comparable in patient and healthy B-cells. Functional analysis of L3P-BLK showed reduced BCR crosslinking-induced Syk phosphorylation and proliferation, in both primary B-cells and B-LCLs. B-cells expressing L3P-BLK showed accelerated destruction of BCR-internalized antigen and reduced ability to elicit CD40L-expression on antigen-specific CD4(+) T-cells.In conclusion, we found a novel BLK gene variant in CVID-patients that causes suppressed B-cell proliferation and reduced ability of B-cells to elicit antigen-specific CD4(+) T-cell responses. Both these mechanisms may contribute to hypogammaglobulinemia in CVID-patients.
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29
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Argyropoulos KV, Vogel R, Ziegler C, Altan-Bonnet G, Velardi E, Calafiore M, Dogan A, Arcila M, Patel M, Knapp K, Mallek C, Hunter ZR, Treon SP, van den Brink MRM, Palomba ML. Clonal B cells in Waldenström's macroglobulinemia exhibit functional features of chronic active B-cell receptor signaling. Leukemia 2016; 30:1116-25. [PMID: 26867669 PMCID: PMC4858584 DOI: 10.1038/leu.2016.8] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 11/23/2015] [Accepted: 12/22/2015] [Indexed: 12/19/2022]
Abstract
Waldenström's macroglobulinemia (WM) is a B-cell non-Hodgkin's lymphoma (B-NHL) characterized by immunoglobulin M (IgM) monoclonal gammopathy and the medullary expansion of clonal lymphoplasmacytic cells. Neoplastic transformation has been partially attributed to hyperactive MYD88 signaling, secondary to the MYD88 L265P mutation, occurring in the majority of WM patients. Nevertheless, the presence of chronic active B-cell receptor (BCR) signaling, a feature of multiple IgM+ B-NHL, remains a subject of speculation in WM. Here, we interrogated the BCR signaling capacity of primary WM cells by utilizing multiparametric phosphoflow cytometry and found heightened basal phosphorylation of BCR-related signaling proteins, and augmented phosphoresponses on surface IgM (sIgM) crosslinking, compared with normal B cells. In support of those findings we observed high sIgM expression and loss of phosphatase activity in WM cells, which could both lead to signaling potentiation in clonal cells. Finally, led by the high-signaling heterogeneity among WM samples, we generated patient-specific phosphosignatures, which subclassified patients into a ‘high' and a ‘healthy-like' signaling group, with the second corresponding to patients with a more indolent clinical phenotype. These findings support the presence of chronic active BCR signaling in WM while providing a link between differential BCR signaling utilization and distinct clinical WM subgroups.
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Affiliation(s)
- K V Argyropoulos
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - R Vogel
- Computational Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - C Ziegler
- Computational Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - G Altan-Bonnet
- Computational Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - E Velardi
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - M Calafiore
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - A Dogan
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - M Arcila
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - M Patel
- Hematologic Oncology Tissue Bank, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - K Knapp
- Hematologic Oncology Tissue Bank, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - C Mallek
- Hematologic Oncology Tissue Bank, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Z R Hunter
- Bing Center for Waldenström's Macroglobulinemia, Dana Farber Cancer Institute, Boston, MA, USA
| | - S P Treon
- Bing Center for Waldenström's Macroglobulinemia, Dana Farber Cancer Institute, Boston, MA, USA
| | - M R M van den Brink
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA.,Lymphoma Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - M L Palomba
- Lymphoma Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA
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30
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Mavropoulos A, Simopoulou T, Varna A, Liaskos C, Katsiari CG, Bogdanos DP, Sakkas LI. Breg Cells Are Numerically Decreased and Functionally Impaired in Patients With Systemic Sclerosis. Arthritis Rheumatol 2016; 68:494-504. [DOI: 10.1002/art.39437] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 09/10/2015] [Indexed: 12/13/2022]
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31
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Nicholas KJ, Greenplate AR, Flaherty DK, Matlock BK, Juan JS, Smith RM, Irish JM, Kalams SA. Multiparameter analysis of stimulated human peripheral blood mononuclear cells: A comparison of mass and fluorescence cytometry. Cytometry A 2015; 89:271-80. [PMID: 26599989 DOI: 10.1002/cyto.a.22799] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 10/28/2015] [Accepted: 10/30/2015] [Indexed: 12/29/2022]
Abstract
Mass and fluorescence cytometry are quantitative single cell flow cytometry approaches that are powerful tools for characterizing diverse tissues and cellular systems. Here mass cytometry was directly compared with fluorescence cytometry by studying phenotypes of healthy human peripheral blood mononuclear cells (PBMC) in the context of superantigen stimulation. One mass cytometry panel and five fluorescence cytometry panels were used to measure 20 well-established lymphocyte markers of memory and activation. Comparable frequencies of both common and rare cell subpopulations were observed with fluorescence and mass cytometry using biaxial gating. The unsupervised high-dimensional analysis tool viSNE was then used to analyze data sets generated from both mass and fluorescence cytometry. viSNE analysis effectively characterized PBMC using eight features per cell and identified similar frequencies of activated CD4+ T cells with both technologies. These results suggest combinations of unsupervised analysis programs and extended multiparameter cytometry will be indispensable tools for detecting perturbations in protein expression in both health and disease.
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Affiliation(s)
- Katherine J Nicholas
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Allison R Greenplate
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee.,Department of Cancer Biology and Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - David K Flaherty
- Flow Cytometry Shared Resource, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Brittany K Matlock
- Flow Cytometry Shared Resource, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Juan San Juan
- Division of Infectious Diseases, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Rita M Smith
- Division of Infectious Diseases, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Jonathan M Irish
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee.,Department of Cancer Biology and Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Spyros A Kalams
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee.,Division of Infectious Diseases, Vanderbilt University School of Medicine, Nashville, Tennessee
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32
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Polikowsky HG, Wogsland CE, Diggins KE, Huse K, Irish JM. Cutting Edge: Redox Signaling Hypersensitivity Distinguishes Human Germinal Center B Cells. THE JOURNAL OF IMMUNOLOGY 2015; 195:1364-1367. [PMID: 26157177 DOI: 10.4049/jimmunol.1500904] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 06/11/2015] [Indexed: 12/22/2022]
Abstract
Differences in the quality of BCR signaling control key steps of B cell maturation and differentiation. Endogenously produced H2O2 is thought to fine tune the level of BCR signaling by reversibly inhibiting phosphatases. However, relatively little is known about how B cells at different stages sense and respond to such redox cues. In this study, we used phospho-specific flow cytometry and high-dimensional mass cytometry (CyTOF) to compare BCR signaling responses in mature human tonsillar B cells undergoing germinal center (GC) reactions. GC B cells, in contrast to mature naive B cells, memory B cells, and plasmablasts, were hypersensitive to a range of H2O2 concentrations and responded by phosphorylating SYK and other membrane-proximal BCR effectors in the absence of BCR engagement. These findings reveal that stage-specific redox responses distinguish human GC B cells.
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Affiliation(s)
- Hannah G Polikowsky
- Department of Pathology, Microbiology, and Immunology, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN, USA.,Cancer Biology, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Cara E Wogsland
- Department of Pathology, Microbiology, and Immunology, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Kirsten E Diggins
- Cancer Biology, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Kanutte Huse
- Centre for Cancer Biomedicine, University of Oslo, Oslo University Hospital, Oslo, Norway.,Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Jonathan M Irish
- Department of Pathology, Microbiology, and Immunology, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN, USA.,Cancer Biology, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN, USA
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33
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Hansmann L, Blum L, Ju CH, Liedtke M, Robinson WH, Davis MM. Mass cytometry analysis shows that a novel memory phenotype B cell is expanded in multiple myeloma. Cancer Immunol Res 2015; 3:650-60. [PMID: 25711758 DOI: 10.1158/2326-6066.cir-14-0236-t] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 02/12/2015] [Indexed: 12/13/2022]
Abstract
It would be very beneficial if the status of cancers could be determined from a blood specimen. However, peripheral blood leukocytes are very heterogeneous between individuals, and thus high-resolution technologies are likely required. We used cytometry by time-of-flight and next-generation sequencing to ask whether a plasma cell cancer (multiple myeloma) and related precancerous states had any consistent effect on the peripheral blood mononuclear cell phenotypes of patients. Analysis of peripheral blood samples from 13 cancer patients, 9 precancer patients, and 9 healthy individuals revealed significant differences in the frequencies of the T-cell, B-cell, and natural killer-cell compartments. Most strikingly, we identified a novel B-cell population that normally accounts for 4.0% ± 0.7% (mean ± SD) of total B cells and is up to 13-fold expanded in multiple myeloma patients with active disease. This population expressed markers previously associated with both memory (CD27(+)) and naïve (CD24(lo)CD38(+)) phenotypes. Single-cell immunoglobulin gene sequencing showed polyclonality, indicating that these cells are not precursors to the myeloma, and somatic mutations, a characteristic of memory cells. SYK, ERK, and p38 phosphorylation responses, and the fact that most of these cells expressed isotypes other than IgM or IgD, confirmed the memory character of this population, defining it as a novel type of memory B cells.
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Affiliation(s)
- Leo Hansmann
- Department of Microbiology and Immunology, Stanford University, Stanford, California
| | - Lisa Blum
- Division of Immunology and Rheumatology, Stanford University, Stanford, California
| | - Chia-Hsin Ju
- Division of Immunology and Rheumatology, Stanford University, Stanford, California
| | - Michaela Liedtke
- Division of Hematology, Department of Medicine, Stanford University, Stanford, California
| | - William H Robinson
- Division of Immunology and Rheumatology, Stanford University, Stanford, California
| | - Mark M Davis
- Department of Microbiology and Immunology, Stanford University, Stanford, California. Institute for Immunity, Transplantation, and Infection, Stanford University, Stanford, California. The Howard Hughes Medical Institute, Stanford University, Stanford, California.
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34
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Lipchik AM, Perez M, Bolton S, Dumrongprechachan V, Ouellette SB, Cui W, Parker LL. KINATEST-ID: a pipeline to develop phosphorylation-dependent terbium sensitizing kinase assays. J Am Chem Soc 2015; 137:2484-94. [PMID: 25689372 DOI: 10.1021/ja507164a] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Nonreceptor protein tyrosine kinases (NRTKs) are essential for cellular homeostasis and thus are a major focus of current drug discovery efforts. Peptide substrates that can enhance lanthanide ion luminescence upon tyrosine phosphorylation enable rapid, sensitive screening of kinase activity, however design of suitable substrates that can distinguish between tyrosine kinase families is a huge challenge. Despite their different substrate preferences, many NRTKs are structurally similar even between families. Furthermore, the development of lanthanide-based kinase assays is hampered by incomplete understanding of how to integrate sequence selectivity with metal ion binding, necessitating laborious iterative substrate optimization. We used curated proteomic data from endogenous kinase substrates and known Tb(3+)-binding sequences to build a generalizable in silico pipeline with tools to generate, screen, align, and select potential phosphorylation-dependent Tb(3+)-sensitizing substrates that are most likely to be kinase specific. We demonstrated the approach by developing several substrates that are selective within kinase families and amenable to high-throughput screening (HTS) applications. Overall, this strategy represents a pipeline for developing efficient and specific assays for virtually any tyrosine kinase that use HTS-compatible lanthanide-based detection. The tools provided in the pipeline also have the potential to be adapted to identify peptides for other purposes, including other enzyme assays or protein-binding ligands.
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Affiliation(s)
- Andrew M Lipchik
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Center for Cancer Research, Purdue University , West Lafayette, Indiana 47907
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Spurgeon BEJ, Aburima A, Oberprieler NG, Taskén K, Naseem KM. Multiplexed phosphospecific flow cytometry enables large-scale signaling profiling and drug screening in blood platelets. J Thromb Haemost 2014; 12:1733-43. [PMID: 25056834 DOI: 10.1111/jth.12670] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 06/14/2014] [Indexed: 02/03/2023]
Abstract
BACKGROUND Dissecting the signaling events that contribute to platelet activation will increase our understanding of platelet function and aid in the development of new antiplatelet agents. However, high-throughput methodology for the quantitative analysis of platelet signaling events is still lacking. OBJECTIVE To develop a high-throughput assay for the analysis of platelet signaling events in whole blood. METHODS AND RESULTS We developed a fluorescent barcoding protocol to facilitate multiplexing and enable large-scale signaling profiling in platelets in whole blood. The methodology allowed simultaneous staining and acquisition of 24-96 samples in a single analysis tube with a standard flow cytometer. This approach significantly reduced experimental numbers, data acquisition time, and antibody consumption, while providing automated statistically rich quantitative data on signaling events. Using vasodilator-stimulated phosphoprotein (VASP), an established marker of platelet inhibition and antiplatelet drug therapy, we demonstrated that the assay could detect subtle changes in phosphoVASP-Ser157/239 in response to cAMP-elevating agents of varying potency and known modulators of the cAMP signaling cascade. The assay could be used with washed platelets or whole blood, analyzed immediately or frozen, without any significant change in assay performance. To demonstrate the usefulness of the assay as a drug discovery platform, we examined a prostaglandin screening library. Our screen of 70 prostaglandin derivatives revealed three previously uncharacterized lipids that stimulated phosphorylation of VASP-Ser157. Follow-up analyses demonstrated that these agents elevated intraplatelet cAMP and inhibited collagen-induced platelet aggregation. CONCLUSIONS This novel method enables rapid, large-scale quantitative signaling profiling and compound screening in human platelets present in whole blood.
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Affiliation(s)
- B E J Spurgeon
- Centre for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, UK
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Purssell E. Cyclooxygenase inhibitors inhibit antibody response through interference with MAPK/ERK pathways and BLIMP-1 inhibition. Med Hypotheses 2014; 83:372-7. [PMID: 25012778 DOI: 10.1016/j.mehy.2014.06.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 06/09/2014] [Accepted: 06/17/2014] [Indexed: 11/16/2022]
Abstract
Fever is a common symptom of illness in children, and although not harmful in itself, fever and its associated symptoms are often treated with antipyretic drugs. A number of national and other guidelines now recommend against their routine use; a conclusion that was initially supported by a study showing that the prophylactic use of paracetamol might reduce antibody response to some vaccine antigens, although data from booster vaccinations are more equivocal. Although in vivo data on the cause of this inhibition are scarce, in vitro data suggests that the cause may be due to inhibition of the mitogen activated protein kinase/extracellular regulated protein kinase pathways, and a subsequent reduction in the process of plasma cell differentiation at the beginning of the antibody response. This suggests that in high-risk patients these drugs could be avoided in the early part of an infection when plasma-cell differentiation is occurring. More data are needed to define this period; until then existing data support the recommendation against the routine use of these drugs.
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Affiliation(s)
- E Purssell
- King's College London, James Clerk Maxwell Building, 57 Waterloo Road, London SE1 8WA, United Kingdom.
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Elements of the B cell signalosome are differentially affected by mercury intoxication. Autoimmune Dis 2014; 2014:239358. [PMID: 24876949 PMCID: PMC4024408 DOI: 10.1155/2014/239358] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 01/07/2014] [Accepted: 01/20/2014] [Indexed: 01/30/2023] Open
Abstract
It has been suggested that environmental exposures to mercury contribute to autoimmune disease. Disruption of BCR signaling is associated with failure of central tolerance and autoimmunity, and we have previously shown that low levels of Hg2+ interfere with BCR signaling. In this report we have employed multiparametric phosphoflow cytometry, as well as a novel generalization of the Overton algorithm from one- to two-dimensional unimodal distributions to simultaneously monitor the effect of low level Hg2+ intoxication on activation of ERK and several upstream elements of the BCR signaling pathway in WEHI-231 B cells. We have found that, after exposure to low levels of Hg2+, only about a third of the cells are sensitive to the metal. For those cells which are sensitive, we confirm our earlier work that activation of ERK is attenuated but now report that Hg2+ has little upstream effect on the Btk tyrosine kinase. On the other hand, we find that signaling upstream through the Syk tyrosine kinase is actually augmented, as is upstream activation of the B cell signalosome scaffolding protein BLNK.
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Stimulation of the B-cell receptor activates the JAK2/STAT3 signaling pathway in chronic lymphocytic leukemia cells. Blood 2014; 123:3797-802. [PMID: 24778152 DOI: 10.1182/blood-2013-10-534073] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In chronic lymphocytic leukemia (CLL), stimulation of the B-cell receptor (BCR) triggers survival signals. Because in various cells activation of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway provides cells with survival advantage, we wondered whether BCR stimulation activates the JAK/STAT pathway in CLL cells. To stimulate the BCR we incubated CLL cells with anti-IgM antibodies. Anti-IgM antibodies induced transient tyrosine phosphorylation and nuclear localization of phosphorylated (p) STAT3. Immunoprecipitation studies revealed that anti-JAK2 antibodies coimmunoprecipitated pSTAT3 and pJAK2 in IgM-stimulated but not unstimulated CLL cells, suggesting that activation of the BCR induces activation of JAK2, which phosphorylates STAT3. Incubation of CLL cells with the JAK1/2 inhibitor ruxolitinib inhibited IgM-induced STAT3 phosphorylation and induced apoptosis of IgM-stimulated but not unstimulated CLL cells in a dose- and time-dependent manner. Whether ruxolitinib treatment would benefit patients with CLL remains to be determined.
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Cesano A, Spellmeyer D. Immune system functional pathway analysis using single cell network profiling (SCNP): a novel tool in cancer immunotherapy. Methods Mol Biol 2014; 1102:583-99. [PMID: 24259000 DOI: 10.1007/978-1-62703-727-3_31] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The development of cancer immunotherapies has been ongoing for many years and has shown limited success. Novel biomarkers are needed to identify patients most likely to respond to anticancer immune-therapeutic approaches. Moreover, a systems-level approach is required for comprehensive understanding of the interconnected components, pathways, and cell types associated with an immune response. In this chapter, we describe single cell network profiling (SCNP), a novel method for assessing and measuring immune function/dysfunction at a systems level. SCNP is a multiparametric flow-cytometry-based analysis that can simultaneously measure, at the single cell level, both extracellular surface markers and changes in intracellular signaling proteins in response to extracellular modulators. Measuring changes in signaling proteins following the application of an external modulation informs on the functional capacity of the signaling network which cannot be assessed by the measurement of basal signaling alone. In addition, the simultaneous analysis of multiple pathways in multiple cell subsets can provide insight into the connectivity of both cell signaling networks and immune cell subtypes. The experimental steps associated with an SCNP assay are (1) pre-analytical sample preparation; (2) modulation for functional analysis; (3) staining with antibody cocktail; (4) data acquisition on flow cytometer; and (5) data analysis and metrics. Important considerations for each step of the assay will be discussed, and data demonstrating the utility of SCNP for immune monitoring applications will be summarized.
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Woo J, Baumann A, Arguello V. Recent advancements of flow cytometry: new applications in hematology and oncology. Expert Rev Mol Diagn 2013; 14:67-81. [DOI: 10.1586/14737159.2014.862153] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Johnsen HE, Bergkvist KS, Schmitz A, Kjeldsen MK, Hansen SM, Gaihede M, Nørgaard MA, Bæch J, Grønholdt ML, Jensen FS, Johansen P, Bødker JS, Bøgsted M, Dybkær K. Cell of origin associated classification of B-cell malignancies by gene signatures of the normal B-cell hierarchy. Leuk Lymphoma 2013; 55:1251-60. [DOI: 10.3109/10428194.2013.839785] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Bjornson ZB, Nolan GP, Fantl WJ. Single-cell mass cytometry for analysis of immune system functional states. Curr Opin Immunol 2013; 25:484-94. [PMID: 23999316 DOI: 10.1016/j.coi.2013.07.004] [Citation(s) in RCA: 159] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Revised: 07/05/2013] [Accepted: 07/08/2013] [Indexed: 01/11/2023]
Abstract
Mass cytometry facilitates high-dimensional, quantitative analysis of the effects of bioactive molecules on cell populations at single-cell resolution. Datasets are generated with panels of up to 45 antibodies. Each antibody is conjugated to a polymer chelated with a stable metal isotope, usually in the lanthanide series of the periodic table. Antibody panels recognize surface markers to delineate cell types simultaneously with intracellular signaling molecules to measure biological functions, such as metabolism, survival, DNA damage, cell cycle and apoptosis, to provide an overall determination of the network state of an individual cell. This review will cover the basics of mass cytometry as well as outline assays developed for the platform that enhance the immunologist's analytical arsenal.
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Affiliation(s)
- Zach B Bjornson
- Stanford University School of Medicine, Department of Microbiology & Immunology, Baxter Laboratory for Stem Cell Biology, 269 Campus Drive, Stanford, CA 94305-5175, USA
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Anti-tumor activity of obinutuzumab and rituximab in a follicular lymphoma 3D model. Blood Cancer J 2013; 3:e131. [PMID: 23933705 PMCID: PMC3763386 DOI: 10.1038/bcj.2013.32] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 07/03/2013] [Accepted: 07/15/2013] [Indexed: 11/23/2022] Open
Abstract
Follicular lymphomas (FLs) account for 35–40% of all adult lymphomas. Treatment typically involves chemotherapy combined with the anti-CD20 monoclonal antibody (MAb) rituximab (RTX). The development of the type II anti-CD20 MAb obinutuzumab (GA101) aims to further improve treatment. Here, using FL cells we show that RTX and GA101 display a similar activity on RL cells cultured in 2D. However, 2D culture cannot mimic tumor spatial organization and conventional 2D models may not reflect the effects of antibodies as they occur in vivo. Thus, we created a non-Hodgkin's lymphoma (NHL) 3D culture system, termed multicellular aggregates of lymphoma cells (MALC), and used it to compare RTX and GA101 activity. Our results show that both antibodies display greater activity towards FL cells in 3D culture compared with 2D culture. Moreover, we observed that in the 3D model GA101 was more effective than RTX both in inhibiting MALC growth through induction of (lysosomal) cell death and senescence and in inhibiting intracellular signaling pathways, such as mammalian target of rapamycin, Akt, PLCgamma (Phospholipase C gamma) and Syk. Altogether, our study demonstrates that spatial organization strongly influences the response to antibody treatment, supporting the use of 3D models for the testing of therapeutic agents in NHL.
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Abstract
The B-cell receptor (BCR) signaling pathway plays an essential role in the survival, proliferation, differentiation and trafficking of lymphocytic. Recent findings associate aberrant BCR signaling with specific disease pathologies, including B-cell malignancies and autoimmune disorders. Inhibition of the BCR signaling pathway may therefore provide promising new strategies for the treatment of B-cell diseases. This special issue of International Reviews of Immunology focuses on atypical B-cell receptor signaling, its role in immune diseases and cancer, and its implications for potential therapeutic intervention.
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Hatton O, Lambert SL, Phillips LK, Vaysberg M, Natkunam Y, Esquivel CO, Krams SM, Martinez OM. Syk-induced phosphatidylinositol-3-kinase activation in Epstein-Barr virus posttransplant lymphoproliferative disorder. Am J Transplant 2013; 13:883-890. [PMID: 23398911 PMCID: PMC4008139 DOI: 10.1111/ajt.12137] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Revised: 11/19/2012] [Accepted: 12/06/2012] [Indexed: 01/25/2023]
Abstract
Posttransplant lymphoproliferative disorder (PTLD)-associated Epstein-Barr virus (EBV)+ B cell lymphomas are serious complications of solid organ and bone marrow transplantation. The EBV protein LMP2a, a B cell receptor (BCR) mimic, provides survival signals to virally infected cells through Syk tyrosine kinase. Therefore, we explored whether Syk inhibition is a viable therapeutic strategy for EBV-associated PTLD. We have shown that R406, the active metabolite of the Syk inhibitor fostamatinib, induces apoptosis and cell cycle arrest while decreasing downstream phosphatidylinositol-3'-kinase (PI3K)/Akt signaling in EBV+ B cell lymphoma PTLD lines in vitro. However, Syk inhibition did not inhibit or delay the in vivo growth of solid tumors established from EBV-infected B cell lines. Instead, we observed tumor growth in adjacent inguinal lymph nodes exclusively in fostamatinib-treated animals. In contrast, direct inhibition of PI3K/Akt significantly reduced tumor burden in a xenogeneic mouse model of PTLD without evidence of tumor growth in adjacent inguinal lymph nodes. Taken together, our data indicate that Syk activates PI3K/Akt signaling which is required for survival of EBV+ B cell lymphomas. PI3K/Akt signaling may be a promising therapeutic target for PTLD, and other EBV-associated malignancies.
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Affiliation(s)
- O. Hatton
- Program in Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA,Department of Surgery / Division of Abdominal Transplantation, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - S. L. Lambert
- Program in Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA,Department of Surgery / Division of Abdominal Transplantation, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - L. K. Phillips
- Program in Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA,Department of Surgery / Division of Abdominal Transplantation, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - M. Vaysberg
- Program in Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA,Department of Surgery / Division of Abdominal Transplantation, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Y. Natkunam
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - C. O. Esquivel
- Department of Surgery / Division of Abdominal Transplantation, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - S. M. Krams
- Program in Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA,Department of Surgery / Division of Abdominal Transplantation, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - O. M. Martinez
- Program in Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA,Department of Surgery / Division of Abdominal Transplantation, Stanford University School of Medicine, Stanford, CA 94305, USA
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Parker LL, Kron SJ. Kinase activation in circulating cells: opportunities for biomarkers for diagnosis and therapeutic monitoring. ACTA ACUST UNITED AC 2013; 2:33-46. [PMID: 23485115 DOI: 10.1517/17530059.2.1.33] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A clinically useful tool to assay phosphorylation-dependent signaling in circulating cells has the potential to provide a wealth of information about a patient's health, including information unavailable by any other method. Patterns of kinase activation, such as the abnormal signaling characteristic of myeloproliferative disorders, may offer highly specific biomarkers for diagnosis or monitoring the efficacy of therapeutics. For assays of kinase activity in circulating leukocytes to be standardized, let alone made practical for the clinic, numerous technical hurdles must be overcome. In this review the current status of analysis of kinase signaling in circulating cells and recent progress in biomarker discovery and validation is discussed. Looking forward, the potential value of signaling patterns as complex biomarkers and the resulting need for future development of robust, multiplexed assays of kinase activation is addressed.
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Affiliation(s)
- Laurie L Parker
- University of Chicago, Ludwig Center for Metastasis Research, Knapp R322, 924 E. 57th Street, Chicago, IL 6063, USA
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High PD-1 expression and suppressed cytokine signaling distinguish T cells infiltrating follicular lymphoma tumors from peripheral T cells. Blood 2013; 121:1367-76. [PMID: 23297127 DOI: 10.1182/blood-2012-04-421826] [Citation(s) in RCA: 131] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Defects in T-cell function in patients with cancer might influence their capacity to mount efficient antitumor immune responses. Here, we identified highly reduced IL-4-, IL-10-, and IL-21-induced phosphorylation of STAT6 and STAT3 in tumor-infiltrating T cells (TILs) in follicular lymphoma (FL) tumors, contrasting other non-Hodgkin lymphoma TILs. By combining phospho-protein-specific flow cytometry with several T-cell markers, we identified that CD4(+)CD45RO(+)CD62L(-) FL TILs were largely nonresponsive to cytokines, in contrast to the corresponding autologous peripheral blood subset. We observed differential expression of the inhibitory receptor PD-1 in FL TILs and peripheral blood T cells. Furthermore, CD4(+)PD-1(hi) FL TILs, containing T(FH) and non-T(FH) cells, had lost their cytokine responsiveness, whereas PD-1 TILs had normal cytokine signaling. However, this phenomenon was not tumor specific, because tonsil T cells were similar to FL TILs. FL tumor cells were negative for PD-1 ligands, but PD-L1(+) histiocytes were found within the T cell-rich zone of the neoplastic follicles. Disruption of the microenvironment and in vitro culture of FL TILs could restore cytokine signaling in the PD-1(hi) subset. Because FL TILs in vivo probably receive suppressive signals through PD-1, this provides a rationale for testing PD-1 Ab in combination with immunotherapy in patients with FL.
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Toapanta FR, Bernal PJ, Sztein MB. Diverse phosphorylation patterns of B cell receptor-associated signaling in naïve and memory human B cells revealed by phosphoflow, a powerful technique to study signaling at the single cell level. Front Cell Infect Microbiol 2012; 2:128. [PMID: 23087912 PMCID: PMC3473368 DOI: 10.3389/fcimb.2012.00128] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2012] [Accepted: 10/01/2012] [Indexed: 11/13/2022] Open
Abstract
Following interaction with cognate antigens, B cells undergo cell activation, proliferation, and differentiation. Ligation of the B cell receptor (BCR) leads to the phosphorylation of BCR-associated signaling proteins within minutes of antigen binding, a process with profound consequences for the fate of the cells and development of effector immunity. Phosphoflow allows a rapid evaluation of various signaling pathways in complex heterogenous cell subsets. This novel technique was used in combination with multi-chromatic flow cytometry (FC) and fluorescent-cell barcoding (FCB) to study phosphorylation of BCR-associated signaling pathways in naïve and memory human B cell subsets. Proteins of the initiation (Syk), propagation (Btk, Akt), and integration (p38MAPK and Erk1/2) signaling units were studied. Switched memory (Sm) CD27+ and Sm CD27- phosphorylation patterns were similar when stimulated with anti-IgA or -IgG. In contrast, naïve and unswitched memory (Um) cells showed significant differences following IgM stimulation. Enhanced phosphorylation of Syk was observed in Um cells, suggesting a lower activation threshold. This is likely the result of higher amounts of IgM on the cell surface, higher pan-Syk levels, and enhanced susceptibility to phosphatase inhibition. All other signaling proteins evaluated also showed some degree of enhanced phosphorylation in Um cells. Furthermore, both the phospholipase C-γ2 (PLC-γ2) and phosphatidylinositol 3-kinase (PI3K) pathways were activated in Um cells, while only the PI3K pathway was activated on naïve cells. Um cells were the only ones that activated signaling pathways when stimulated with fluorescently labeled S. Typhi and S. pneumoniae. Finally, simultaneous evaluation of signaling proteins at the single cell level (multiphosphorylated cells) revealed that interaction with gram positive and negative bacteria resulted in complex and diverse signaling patterns. Phosphoflow holds great potential to accelerate vaccine development by identifying signaling profiles in good/poor responders.
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Affiliation(s)
- Franklin R Toapanta
- Department of Medicine, Center for Vaccine Development, University of Maryland Baltimore, MD, USA
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Blix ES, Irish JM, Husebekk A, Delabie J, Forfang L, Tierens AM, Myklebust JH, Kolstad A. Phospho-specific flow cytometry identifies aberrant signaling in indolent B-cell lymphoma. BMC Cancer 2012; 12:478. [PMID: 23072591 PMCID: PMC3519597 DOI: 10.1186/1471-2407-12-478] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 10/12/2012] [Indexed: 11/10/2022] Open
Abstract
Background Knowledge about signaling pathways in malignant cells may provide prognostic and diagnostic information in addition to identify potential molecular targets for therapy. B-cell receptor (BCR) and co-receptor CD40 signaling is essential for normal B cells, and there is increasing evidence that signaling via BCR and CD40 plays an important role in the pathogenesis of B-cell lymphoma. The aim of this study was to investigate basal and induced signaling in lymphoma B cells and infiltrating T cells in single-cell suspensions of biopsies from small cell lymphocytic lymphoma/chronic lymphocytic leukemia (SLL/CLL) and marginal zone lymphoma (MZL) patients. Methods Samples from untreated SLL/CLL and MZL patients were examined for basal and activation induced signaling by phospho-specific flow cytometry. A panel of 9 stimulation conditions targeting B and T cells, including crosslinking of the B cell receptor (BCR), CD40 ligand and interleukins in combination with 12 matching phospho-protein readouts was used to study signaling. Results Malignant B cells from SLL/CLL patients had higher basal levels of phosphorylated (p)-SFKs, p-PLCγ, p-ERK, p-p38, p-p65 (NF-κB), p-STAT5 and p-STAT6, compared to healthy donor B cells. In contrast, anti-BCR induced signaling was highly impaired in SLL/CLL and MZL B cells as determined by low p-SFK, p-SYK and p-PLCγ levels. Impaired anti-BCR-induced p-PLCγ was associated with reduced surface expression of IgM and CD79b. Similarly, CD40L-induced p-ERK and p-p38 were also significantly reduced in lymphoma B cells, whereas p-p65 (NF-κB) was equal to that of normal B cells. In contrast, IL-2, IL-7 and IL-15 induced p-STAT5 in tumor-infiltrating T cells were not different from normal T cells. Conclusions BCR signaling and CD40L-induced p-p38 was suppressed in malignant B cells from SLL/CLL and MZL patients. Single-cell phospho-specific flow cytometry for detection of basal as well as activation-induced phosphorylation of signaling proteins in distinct cell populations can be used to identify aberrant signaling pathways.
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Affiliation(s)
- Egil S Blix
- Department of Oncology, University Hospital of North Norway, Tromsø, Norway.
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Lipchik AM, Killins RL, Geahlen RL, Parker LL. A peptide-based biosensor assay to detect intracellular Syk kinase activation and inhibition. Biochemistry 2012; 51:7515-24. [PMID: 22920457 DOI: 10.1021/bi300970h] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Spleen tyrosine kinase (Syk) has been implicated in a number of pathologies including cancer and rheumatoid arthritis and thus has been pursued as a novel therapeutic target. Because of the complex relationship between Syk's auto- and other internal phosphorylation sites, scaffolding proteins, enzymatic activation state and sites of phosphorylation on its known substrates, the role of Syk's activity in these diseases has not been completely clear. To approach such analyses, we developed a Syk-specific artificial peptide biosensor (SAStide) to use in a cell-based assay for direct detection of intracellular Syk activity and inhibition in response to physiologically relevant stimuli in both laboratory cell lines and primary splenic B cells. This peptide contains a sequence derived from known Syk substrate preference motifs linked to a cell permeable peptide, resulting in a biosensor that is phosphorylated in live cells in a Syk-dependent manner, thus serving as a reporter of Syk catalytic activity in intact cells. Because the assay is compatible with live, primary cells and can report pharmacodynamics for drug action on an intended target, this methodology could be used to facilitate a better understanding of Syk's function and the effect of its inhibition in disease.
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Affiliation(s)
- Andrew M Lipchik
- Department of Medicinal Chemistry and Molecular Pharmacology and Purdue Center for Cancer Research, Purdue University, West Lafayette, IN 47907, USA
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