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Hoeger S, Drake LA, Drake JR. Proximity-Based Labeling Identifies MHC Class II and CD37 as B Cell Receptor-Proximal Proteins with Immunological Functions. Immunohorizons 2024; 8:326-338. [PMID: 38625120 PMCID: PMC11066716 DOI: 10.4049/immunohorizons.2400014] [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: 02/09/2024] [Accepted: 04/03/2024] [Indexed: 04/17/2024] Open
Abstract
The BCR allows for Ag-driven B cell activation and subsequent Ag endocytosis, processing, and presentation to recruit T cell help. Core drivers of BCR signaling and endocytosis are motifs within the receptor's cytoplasmic tail (primarily CD79). However, BCR function can be tuned by other proximal cellular elements, such as CD20 and membrane lipid microdomains. To identify additional proteins that could modulate BCR function, we used a proximity-based biotinylation technique paired with mass spectrometry to identify molecular neighbors of the murine IgM BCR. Those neighbors include MHC class II molecules, integrins, various transporters, and membrane microdomain proteins. Class II molecules, some of which are invariant chain-associated nascent class II, are a readily detected BCR neighbor. This finding is consistent with reports of BCR-class II association within intracellular compartments. The BCR is also in close proximity to multiple proteins involved in the formation of membrane microdomains, including CD37, raftlin, and Ig superfamily member 8. Known defects in T cell-dependent humoral immunity in CD37 knockout mice suggest a role for CD37 in BCR function. In line with this notion, CRISPR-based knockout of CD37 expression in a B cell line heightens BCR signaling, slows BCR endocytosis, and tempers formation of peptide-class II complexes. These results indicate that BCR molecular neighbors can impact membrane-mediated BCR functions. Overall, a proximity-based labeling technique allowed for identification of multiple previously unknown BCR molecular neighbors, including the tetraspanin protein CD37, which can modulate BCR function.
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Affiliation(s)
- Sean Hoeger
- Department of Immunology and Microbial Disease, Albany Medical College, Albany, NY
| | - Lisa A. Drake
- Department of Immunology and Microbial Disease, Albany Medical College, Albany, NY
| | - James R. Drake
- Department of Immunology and Microbial Disease, Albany Medical College, Albany, NY
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2
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Shelby SA, Veatch SL. The Membrane Phase Transition Gives Rise to Responsive Plasma Membrane Structure and Function. Cold Spring Harb Perspect Biol 2023; 15:a041395. [PMID: 37553204 PMCID: PMC10626261 DOI: 10.1101/cshperspect.a041395] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023]
Abstract
Several groups have recently reported evidence for the emergence of domains in cell plasma membranes when membrane proteins are organized by ligand binding or assembly of membrane proximal scaffolds. These domains recruit and retain components that favor the liquid-ordered phase, adding to a decades-old literature interrogating the contribution of membrane phase separation in plasma membrane organization and function. Here we propose that both past and present observations are consistent with a model in which membranes have a high compositional susceptibility, arising from their thermodynamic state in a single phase that is close to a miscibility phase transition. This rigorous framework naturally allows for both transient structure in the form of composition fluctuations and long-lived structure in the form of induced domains. In this way, the biological tuning of plasma membrane composition enables a responsive compositional landscape that facilitates and augments cellular biochemistry vital to plasma membrane functions.
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Affiliation(s)
- Sarah A Shelby
- Biochemistry & Cellular and Molecular Biology, University of Tennessee Knoxville, Knoxville, Tennessee 37996, USA
| | - Sarah L Veatch
- Program in Biophysics, University of Michigan, Ann Arbor, Michigan 48109, USA
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3
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Kerketta R, Erasmus MF, Wilson BS, Halasz AM, Edwards JS. Spatial Stochastic Model of the Pre-B Cell Receptor. IEEE/ACM TRANSACTIONS ON COMPUTATIONAL BIOLOGY AND BIOINFORMATICS 2023; 20:683-693. [PMID: 35482702 PMCID: PMC10123485 DOI: 10.1109/tcbb.2022.3166149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Survival and proliferation of immature B lymphocytes requires expression and tonic signaling of the pre-B cell receptor (pre-BCR). This low level, ligand-independent signaling is likely achieved through frequent, but short-lived, homo interactions. Tonic signaling is also central in the pathology of precursor B acute lymphoblastic leukemia (B-ALL). In order to understand how repeated, transient events can lead to sustained signaling and to assess the impact of receptor accumulation induced by the membrane landscape, we developed a spatial stochastic model of receptor aggregation and downstream signaling events. Our rule- and agent-based model builds on previous mature BCR signaling models and incorporates novel parameters derived from single particle tracking of pre-BCR on surfaces of two different B-ALL cell lines, 697 and Nalm6. Live cell tracking of receptors on the two cell lines revealed characteristic differences in their dimer dissociation rates and diffusion coefficients. We report here that these differences affect pre-BCR aggregation and consequent signal initiation events. Receptors on Nalm6 cells, which have a lower off-rate and lower diffusion coefficient, more frequently form higher order oligomers than pre-BCR on 697 cells, resulting in higher levels of downstream phosphorylation in the Nalm6 cell line.
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4
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Wu X, Li Y, Zhang W, Zhang J, Chen B, Ge Z. RAC1, a Potential Diagnostic and Prognostic Marker for Diffuse Large B Cell Lymphoma. Cells 2022; 11:cells11244039. [PMID: 36552804 PMCID: PMC9776810 DOI: 10.3390/cells11244039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/27/2022] [Accepted: 11/28/2022] [Indexed: 12/15/2022] Open
Abstract
The gene changes for diagnosis and prognosis of diffuse large B cell lymphoma (DLBCL) still remain unclear. RAC1 was reported to be asso;ciated with the B cell receptor signal pathway, but its relations with DLBCL have not yet been systematically explored. In this study, we have conducted molecular, bioinformatics and clinical analyses by using publicly available data from The Cancer Genome Atlas (TCGA). Wilcoxon signed-rank test and logistic regression were performed to evaluate the association between RAC1 and clinical features in patients. Kaplan-Meier and Cox regression methods were used to examine the impacts of RAC1 expression level on overall survival, and a nomogram was performed to illustrate the correlation between RAC1 and the risk of DLBCL. Our results revealed that the expression level of RAC1 in DLBCL was higher than that in normal tissues or lymphadenitis. High-level expression of RAC1 was significantly associated with clinical stage, as well as being an independent factor affecting overall survival. RAC1 was negatively correlated with Bruton's tyrosine kinase (BTK). The association between RAC1 gene expression and the risk of DLBCL was presented in a nomogram. In conclusion, RAC1 expression patterns may be used to predict the development and prognosis of DLBCL.
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Affiliation(s)
- Xue Wu
- Department of Hematology, The Affiliated Zhongda Hospital, Institute of Hematology, Southeast University, Nanjing 210009, China
| | - Yuan Li
- Department of Oncology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Wandong Zhang
- Department of Cellular & Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
- Human Health Therapeutics Research Centre, National Research Council Canada, Ottawa, ON K1A 0R6, Canada
| | - Jing Zhang
- Department of Hematology, The Affiliated Zhongda Hospital, Institute of Hematology, Southeast University, Nanjing 210009, China
| | - Baoan Chen
- Department of Hematology, The Affiliated Zhongda Hospital, Institute of Hematology, Southeast University, Nanjing 210009, China
| | - Zheng Ge
- Department of Hematology, The Affiliated Zhongda Hospital, Institute of Hematology, Southeast University, Nanjing 210009, China
- Correspondence: ; Tel.: +86-025-83262468
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5
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Illig D, Kotlarz D. Dysregulated inflammasome activity in intestinal inflammation - Insights from patients with very early onset IBD. Front Immunol 2022; 13:1027289. [PMID: 36524121 PMCID: PMC9744759 DOI: 10.3389/fimmu.2022.1027289] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 11/11/2022] [Indexed: 11/30/2022] Open
Abstract
Inflammatory bowel disease (IBD) is a multifactorial disorder triggered by imbalances of the microbiome and immune dysregulations in genetically susceptible individuals. Several mouse and human studies have demonstrated that multimeric inflammasomes are critical regulators of host defense and gut homeostasis by modulating immune responses to pathogen- or damage-associated molecular patterns. In the context of IBD, excessive production of pro-inflammatory Interleukin-1β has been detected in patient-derived intestinal tissues and correlated with the disease severity or failure to respond to anti-tumor necrosis factor therapy. Correspondingly, genome-wide association studies have suggested that single nucleotide polymorphisms in inflammasome components might be associated with risk of IBD development. The relevance of inflammasomes in controlling human intestinal homeostasis has been further exemplified by the discovery of very early onset IBD (VEO-IBD) patients with monogenic defects affecting different molecules in the complex regulatory network of inflammasome activity. This review provides an overview of known causative monogenic entities of VEO-IBD associated with altered inflammasome activity. A better understanding of the molecular mechanisms controlling inflammasomes in monogenic VEO-IBD may open novel therapeutic avenues for rare and common inflammatory diseases.
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Affiliation(s)
- David Illig
- Department of Pediatrics, Dr. von Hauner Children’s Hospital, University Hospital, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Daniel Kotlarz
- Department of Pediatrics, Dr. von Hauner Children’s Hospital, University Hospital, Ludwig-Maximilians-University (LMU), Munich, Germany,Institute of Translational Genomics, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany,*Correspondence: Daniel Kotlarz,
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6
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Ott JA, Haakenson JK, Kelly AR, Christian C, Criscitiello MF, Smider VV. Evolution of surrogate light chain in tetrapods and the relationship between lengths of CDR H3 and VpreB tails. Front Immunol 2022; 13:1001134. [PMID: 36311706 PMCID: PMC9614664 DOI: 10.3389/fimmu.2022.1001134] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 09/20/2022] [Indexed: 12/05/2022] Open
Abstract
In the mammalian immune system, the surrogate light chain (SLC) shapes the antibody repertoire during B cell development by serving as a checkpoint for production of functional heavy chains (HC). Structural studies indicate that tail regions of VpreB contact and cover the third complementarity-determining region of the HC (CDR H3). However, some species, particularly bovines, have CDR H3 regions that may not be compatible with this HC-SLC interaction model. With immense structural and genetic diversity in antibody repertoires across species, we evaluated the genetic origins and sequence features of surrogate light chain components. We examined tetrapod genomes for evidence of conserved gene synteny to determine the evolutionary origin of VpreB1, VpreB2, and IGLL1, as well as VpreB3 and pre-T cell receptor alpha (PTCRA) genes. We found the genes for the SLC components (VpreB1, VpreB2, and IGLL1) only in eutherian mammals. However, genes for PTCRA occurred in all amniote groups and genes for VpreB3 occurred in all tetrapod groups, and these genes were highly conserved. Additionally, we found evidence of a new VpreB gene in non-mammalian tetrapods that is similar to the VpreB2 gene of eutherian mammals, suggesting VpreB2 may have appeared earlier in tetrapod evolution and may be a precursor to traditional VpreB2 genes in higher vertebrates. Among eutherian mammals, sequence conservation between VpreB1 and VpreB2 was low for all groups except rabbits and rodents, where VpreB2 was nearly identical to VpreB1 and did not share conserved synteny with VpreB2 of other species. VpreB2 of rabbits and rodents likely represents a duplicated variant of VpreB1 and is distinct from the VpreB2 of other mammals. Thus, rabbits and rodents have two variants of VpreB1 (VpreB1-1 and VpreB1-2) but no VpreB2. Sequence analysis of VpreB tail regions indicated differences in sequence content, charge, and length; where repertoire data was available, we observed a significant relationship between VpreB2 tail length and maximum DH length. We posit that SLC components co-evolved with immunoglobulin HC to accommodate the repertoire - particularly CDR H3 length and structure, and perhaps highly unusual HC (like ultralong HC of cattle) may bypass this developmental checkpoint altogether.
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Affiliation(s)
- Jeannine A. Ott
- Comparative Immunogenetics Lab, Department of Veterinary Pathobiology, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| | - Jeremy K. Haakenson
- Applied Biomedical Science Institute, San Diego, CA, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States
| | - Abigail R. Kelly
- Applied Biomedical Science Institute, San Diego, CA, United States
| | - Claire Christian
- Comparative Immunogenetics Lab, Department of Veterinary Pathobiology, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| | - Michael F. Criscitiello
- Comparative Immunogenetics Lab, Department of Veterinary Pathobiology, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| | - Vaughn V. Smider
- Applied Biomedical Science Institute, San Diego, CA, United States
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States
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7
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Ton Tran HT, Li C, Chakraberty R, Cairo CW. NEU1 and NEU3 enzymes alter CD22 organization on B cells. BIOPHYSICAL REPORTS 2022; 2:100064. [PMID: 36425332 PMCID: PMC9680808 DOI: 10.1016/j.bpr.2022.100064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 07/19/2022] [Indexed: 06/16/2023]
Abstract
The B cell membrane expresses sialic-acid-binding immunoglobulin-like lectins, also called Siglecs, that are important for modulating immune response. Siglecs have interactions with sialoglycoproteins found on the same membrane (cis-ligands) that result in homotypic and heterotypic receptor clusters. The regulation and organization of these clusters, and their effect on cell activation, is not clearly understood. We investigated the role of human neuraminidase enzymes NEU1 and NEU3 on the clustering of CD22 on B cells using confocal microscopy. We observed that native NEU1 and NEU3 activity influence the cluster size of CD22. Using single-particle tracking, we observed that NEU3 activity increased the lateral mobility of CD22, which was in contrast to the effect of exogenous bacterial NEU enzymes. Moreover, we show that native NEU1 and NEU3 activity influenced cellular Ca2+ levels, supporting a role for these enzymes in regulating B cell activation. Our results establish a role for native NEU activity in modulating CD22 organization and function on B cells.
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Affiliation(s)
- Hanh-Thuc Ton Tran
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Caishun Li
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
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8
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Bertrand J, Dostálová H, Kryštof V, Jorda R, Delgado T, Castro-Alvarez A, Mella J, Cabezas D, Faúndez M, Espinosa-Bustos C, Salas CO. Design, Synthesis, In Silico Studies and Inhibitory Activity towards Bcr-Abl, BTK and FLT3-ITD of New 2,6,9-Trisubstituted Purine Derivatives as Potential Agents for the Treatment of Leukaemia. Pharmaceutics 2022; 14:pharmaceutics14061294. [PMID: 35745866 PMCID: PMC9228270 DOI: 10.3390/pharmaceutics14061294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/13/2022] [Accepted: 06/15/2022] [Indexed: 12/04/2022] Open
Abstract
We report 31 new compounds designed, synthesized and evaluated on Bcr-Abl, BTK and FLT3-ITD as part of our program to develop 2,6,9-trisubstituted purine derivatives as inhibitors of oncogenic kinases. The design was inspired by the chemical structures of well-known kinase inhibitors and our previously developed purine derivatives. The synthesis of these purines was simple and used a microwave reactor for the final step. Kinase assays showed three inhibitors with high selectivity for each protein that were identified: 4f (IC50 = 70 nM for Bcr-Abl), 5j (IC50 = 0.41 μM for BTK) and 5b (IC50 = 0.38 μM for FLT-ITD). The 3D-QSAR analysis and molecular docking studies suggested that two fragments are potent and selective inhibitors of these three kinases: a substitution at the 6-phenylamino ring and the length and volume of the alkyl group at N-9. The N-7 and the N-methyl-piperazine moiety linked to the aminophenyl ring at C-2 are also requirements for obtaining the activity. Furthermore, most of these purine derivatives were shown to have a significant inhibitory effect in vitro on the proliferation of leukaemia and lymphoma cells (HL60, MV4-11, CEM, K562 and Ramos) at low concentrations. Finally, we show that the selected purines (4i, 5b and 5j) inhibit the downstream signalling of the respective kinases in cell models. Thus, this study provides new evidence regarding how certain chemical modifications of purine ring substituents provide novel inhibitors of target kinases as potential anti-leukaemia drugs.
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Affiliation(s)
- Jeanluc Bertrand
- Departamento de Química Orgánica, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, Santiago 7820436, Chile; (J.B.); (T.D.)
| | - Hana Dostálová
- Department of Experimental Biology, Palacký University Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic; (H.D.); (R.J.)
| | - Vladimír Kryštof
- Department of Experimental Biology, Palacký University Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic; (H.D.); (R.J.)
- Correspondence: (V.K.); (C.O.S.)
| | - Radek Jorda
- Department of Experimental Biology, Palacký University Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic; (H.D.); (R.J.)
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 5, 779 00 Olomouc, Czech Republic
| | - Thalía Delgado
- Departamento de Química Orgánica, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, Santiago 7820436, Chile; (J.B.); (T.D.)
| | - Alejandro Castro-Alvarez
- Departamento de Ciencias Preclínicas, Facultad de Medicina, Universidad de La Frontera, Manuel Montt 112, Temuco 4780000, Chile;
| | - Jaime Mella
- Instituto de Química y Bioquímica, Facultad de Ciencias, Universidad de Valparaíso, Avenida Gran Bretaña 1111, Valparaíso 2360102, Chile; (J.M.); (D.C.)
- Facultad de Farmacia, Centro de Investigación Farmacopea Chilena, Universidad de Valparaíso, Avenida Gran Bretaña 1093, Valparaíso 2360102, Chile
| | - David Cabezas
- Instituto de Química y Bioquímica, Facultad de Ciencias, Universidad de Valparaíso, Avenida Gran Bretaña 1111, Valparaíso 2360102, Chile; (J.M.); (D.C.)
| | - Mario Faúndez
- Departamento de Farmacia, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, Santiago 7820436, Chile; (M.F.); (C.E.-B.)
| | - Christian Espinosa-Bustos
- Departamento de Farmacia, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, Santiago 7820436, Chile; (M.F.); (C.E.-B.)
| | - Cristian O. Salas
- Departamento de Química Orgánica, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, Santiago 7820436, Chile; (J.B.); (T.D.)
- Correspondence: (V.K.); (C.O.S.)
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9
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Kara S, Amon L, Lühr JJ, Nimmerjahn F, Dudziak D, Lux A. Impact of Plasma Membrane Domains on IgG Fc Receptor Function. Front Immunol 2020; 11:1320. [PMID: 32714325 PMCID: PMC7344230 DOI: 10.3389/fimmu.2020.01320] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 05/26/2020] [Indexed: 12/13/2022] Open
Abstract
Lipid cell membranes not only represent the physical boundaries of cells. They also actively participate in many cellular processes. This contribution is facilitated by highly complex mixtures of different lipids and incorporation of various membrane proteins. One group of membrane-associated receptors are Fc receptors (FcRs). These cell-surface receptors are crucial for the activity of most immune cells as they bind immunoglobulins such as immunoglobulin G (IgG). Based on distinct mechanisms of IgG binding, two classes of Fc receptors are now recognized: the canonical type I FcγRs and select C-type lectin receptors newly referred to as type II FcRs. Upon IgG immune complex induced cross-linking, these receptors are known to induce a multitude of cellular effector responses in a cell-type dependent manner, including internalization, antigen processing, and presentation as well as production of cytokines. The response is also determined by specific intracellular signaling domains, allowing FcRs to either positively or negatively modulate immune cell activity. Expression of cell-type specific combinations and numbers of receptors therefore ultimately sets a threshold for induction of effector responses. Mechanistically, receptor cross-linking and localization to lipid rafts, i.e., organized membrane microdomains enriched in intracellular signaling proteins, were proposed as major determinants of initial FcR activation. Given that immune cell membranes might also vary in their lipid compositions, it is reasonable to speculate, that the cell membrane and especially lipid rafts serve as an additional regulator of FcR activity. In this article, we aim to summarize the current knowledge on the interplay of lipid rafts and IgG binding FcRs with a focus on the plasma membrane composition and receptor localization in immune cells, the proposed mechanisms underlying this localization and consequences for FcR function with respect to their immunoregulatory capacity.
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Affiliation(s)
- Sibel Kara
- Department of Biology, Institute of Genetics, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Lukas Amon
- Laboratory of Dendritic Cell Biology, Department of Dermatology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Jennifer J Lühr
- Laboratory of Dendritic Cell Biology, Department of Dermatology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany.,Division of Nano-Optics, Max-Planck Institute for the Science of Light, Erlangen, Germany
| | - Falk Nimmerjahn
- Department of Biology, Institute of Genetics, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany.,Medical Immunology Campus Erlangen (MICE), Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany.,Deutsches Zentrum Immuntherapie (DZI), Erlangen, Germany
| | - Diana Dudziak
- Laboratory of Dendritic Cell Biology, Department of Dermatology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany.,Medical Immunology Campus Erlangen (MICE), Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany.,Deutsches Zentrum Immuntherapie (DZI), Erlangen, Germany.,Comprehensive Cancer Center Erlangen-European Metropolitan Area of Nürnberg (CCC ER-EMN), Erlangen, Germany
| | - Anja Lux
- Department of Biology, Institute of Genetics, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany.,Medical Immunology Campus Erlangen (MICE), Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
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10
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Wist M, Meier L, Gutman O, Haas J, Endres S, Zhou Y, Rösler R, Wiese S, Stilgenbauer S, Hobeika E, Henis YI, Gierschik P, Walliser C. Noncatalytic Bruton's tyrosine kinase activates PLCγ 2 variants mediating ibrutinib resistance in human chronic lymphocytic leukemia cells. J Biol Chem 2020; 295:5717-5736. [PMID: 32184360 DOI: 10.1074/jbc.ra119.011946] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/26/2020] [Indexed: 12/25/2022] Open
Abstract
Treatment of patients with chronic lymphocytic leukemia (CLL) with inhibitors of Bruton's tyrosine kinase (BTK), such as ibrutinib, is limited by primary or secondary resistance to this drug. Examinations of CLL patients with late relapses while on ibrutinib, which inhibits BTK's catalytic activity, revealed several mutations in BTK, most frequently resulting in the C481S substitution, and disclosed many mutations in PLCG2, encoding phospholipase C-γ2 (PLCγ2). The PLCγ2 variants typically do not exhibit constitutive activity in cell-free systems, leading to the suggestion that in intact cells they are hypersensitive to Rac family small GTPases or to the upstream kinases spleen-associated tyrosine kinase (SYK) and Lck/Yes-related novel tyrosine kinase (LYN). The sensitivity of the PLCγ2 variants to BTK itself has remained unknown. Here, using genetically-modified DT40 B lymphocytes, along with various biochemical assays, including analysis of PLCγ2-mediated inositol phosphate formation, inositol phospholipid assessments, fluorescence recovery after photobleaching (FRAP) static laser microscopy, and determination of intracellular calcium ([Ca2+] i ), we show that various CLL-specific PLCγ2 variants such as PLCγ2S707Y are hyper-responsive to activated BTK, even in the absence of BTK's catalytic activity and independently of enhanced PLCγ2 phospholipid substrate supply. At high levels of B-cell receptor (BCR) activation, which may occur in individual CLL patients, catalytically-inactive BTK restored the ability of the BCR to mediate increases in [Ca2+] i Because catalytically-inactive BTK is insensitive to active-site BTK inhibitors, the mechanism involving the noncatalytic BTK uncovered here may contribute to preexisting reduced sensitivity or even primary resistance of CLL to these drugs.
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Affiliation(s)
- Martin Wist
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Laura Meier
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Orit Gutman
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Jennifer Haas
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Sascha Endres
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Yuan Zhou
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Reinhild Rösler
- Core Unit Mass Spectrometry and Proteomics, Medical Faculty, Ulm University Medical Center, 89081 Ulm, Germany
| | - Sebastian Wiese
- Core Unit Mass Spectrometry and Proteomics, Medical Faculty, Ulm University Medical Center, 89081 Ulm, Germany
| | - Stephan Stilgenbauer
- Department of Internal Medicine III, Ulm University Medical Center, 89081 Ulm, Germany
| | - Elias Hobeika
- Institute of Immunology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Yoav I Henis
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Peter Gierschik
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, 89081 Ulm, Germany.
| | - Claudia Walliser
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, 89081 Ulm, Germany.
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11
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Urbanczyk S, Stein M, Schuh W, Jäck HM, Mougiakakos D, Mielenz D. Regulation of Energy Metabolism during Early B Lymphocyte Development. Int J Mol Sci 2018; 19:E2192. [PMID: 30060475 PMCID: PMC6121686 DOI: 10.3390/ijms19082192] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 07/25/2018] [Indexed: 01/03/2023] Open
Abstract
The most important feature of humoral immunity is the adaptation of the diversity of newly generated B cell receptors, that is, the antigen receptor repertoire, to the body's own and foreign structures. This includes the transient propagation of B progenitor cells and B cells, which possess receptors that are positively selected via anabolic signalling pathways under highly competitive conditions. The metabolic regulation of early B-cell development thus has important consequences for the expansion of normal or malignant pre-B cell clones. In addition, cellular senescence programs based on the expression of B cell identity factors, such as Pax5, act to prevent excessive proliferation and cellular deviation. Here, we review the basic mechanisms underlying the regulation of glycolysis and oxidative phosphorylation during early B cell development in bone marrow. We focus on the regulation of glycolysis and mitochondrial oxidative phosphorylation at the transition from non-transformed pro- to pre-B cells and discuss some ongoing issues. We introduce Swiprosin-2/EFhd1 as a potential regulator of glycolysis in pro-B cells that has also been linked to Ca2+-mediated mitoflashes. Mitoflashes are bioenergetic mitochondrial events that control mitochondrial metabolism and signalling in both healthy and disease states. We discuss how Ca2+ fluctuations in pro- and pre-B cells may translate into mitoflashes in early B cells and speculate about the consequences of these changes.
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Affiliation(s)
- Sophia Urbanczyk
- Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
| | - Merle Stein
- Department of Internal Medicine V, University Hospital, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
| | - Wolfgang Schuh
- Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
| | - Hans-Martin Jäck
- Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
| | - Dimitrios Mougiakakos
- Institute of Comparative Molecular Endocrinology (CME), University of Ulm, 89081 Ulm, Germany.
| | - Dirk Mielenz
- Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
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12
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Pal Singh S, Dammeijer F, Hendriks RW. Role of Bruton's tyrosine kinase in B cells and malignancies. Mol Cancer 2018; 17:57. [PMID: 29455639 PMCID: PMC5817726 DOI: 10.1186/s12943-018-0779-z] [Citation(s) in RCA: 419] [Impact Index Per Article: 69.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 02/01/2018] [Indexed: 12/14/2022] Open
Abstract
Bruton’s tyrosine kinase (BTK) is a non-receptor kinase that plays a crucial role in oncogenic signaling that is critical for proliferation and survival of leukemic cells in many B cell malignancies. BTK was initially shown to be defective in the primary immunodeficiency X-linked agammaglobulinemia (XLA) and is essential both for B cell development and function of mature B cells. Shortly after its discovery, BTK was placed in the signal transduction pathway downstream of the B cell antigen receptor (BCR). More recently, small-molecule inhibitors of this kinase have shown excellent anti-tumor activity, first in animal models and subsequently in clinical studies. In particular, the orally administered irreversible BTK inhibitor ibrutinib is associated with high response rates in patients with relapsed/refractory chronic lymphocytic leukemia (CLL) and mantle-cell lymphoma (MCL), including patients with high-risk genetic lesions. Because ibrutinib is generally well tolerated and shows durable single-agent efficacy, it was rapidly approved for first-line treatment of patients with CLL in 2016. To date, evidence is accumulating for efficacy of ibrutinib in various other B cell malignancies. BTK inhibition has molecular effects beyond its classic role in BCR signaling. These involve B cell-intrinsic signaling pathways central to cellular survival, proliferation or retention in supportive lymphoid niches. Moreover, BTK functions in several myeloid cell populations representing important components of the tumor microenvironment. As a result, there is currently a considerable interest in BTK inhibition as an anti-cancer therapy, not only in B cell malignancies but also in solid tumors. Efficacy of BTK inhibition as a single agent therapy is strong, but resistance may develop, fueling the development of combination therapies that improve clinical responses. In this review, we discuss the role of BTK in B cell differentiation and B cell malignancies and highlight the importance of BTK inhibition in cancer therapy.
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Affiliation(s)
- Simar Pal Singh
- Department of Pulmonary Medicine, Room Ee2251a, Erasmus MC Rotterdam, PO Box 2040, NL 3000, CA, Rotterdam, The Netherlands.,Department of Immunology, Rotterdam, The Netherlands.,Post graduate school Molecular Medicine, Rotterdam, The Netherlands
| | - Floris Dammeijer
- Department of Pulmonary Medicine, Room Ee2251a, Erasmus MC Rotterdam, PO Box 2040, NL 3000, CA, Rotterdam, The Netherlands.,Post graduate school Molecular Medicine, Rotterdam, The Netherlands.,Erasmus MC Cancer Institute, Erasmus MC, Rotterdam, The Netherlands
| | - Rudi W Hendriks
- Department of Pulmonary Medicine, Room Ee2251a, Erasmus MC Rotterdam, PO Box 2040, NL 3000, CA, Rotterdam, The Netherlands.
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13
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Stein M, Dütting S, Mougiakakos D, Bösl M, Fritsch K, Reimer D, Urbanczyk S, Steinmetz T, Schuh W, Bozec A, Winkler TH, Jäck HM, Mielenz D. A defined metabolic state in pre B cells governs B-cell development and is counterbalanced by Swiprosin-2/EFhd1. Cell Death Differ 2017; 24:1239-1252. [PMID: 28524857 DOI: 10.1038/cdd.2017.52] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 02/10/2017] [Accepted: 03/08/2017] [Indexed: 12/14/2022] Open
Abstract
B-cell development in the bone marrow comprises proliferative and resting phases in different niches. We asked whether B-cell metabolism relates to these changes. Compared to pro B and small pre B cells, large pre B cells revealed the highest glucose uptake and ROS but not mitochondrial mass, whereas small pre B cells exhibited the lowest mitochondrial membrane potential. Small pre B cells from Rag1-/-;33.C9 μ heavy chain knock-in mice revealed decreased glycolysis (ECAR) and mitochondrial spare capacity compared to pro B cells from Rag1-/- mice. We were interested in the step regulating this metabolic switch from pro to pre B cells and uncovered that Swiprosin-2/EFhd1, a Ca2+-binding protein of the inner mitochondrial membrane involved in Ca2+-induced mitoflashes, is expressed in pro B cells, but downregulated by surface pre B-cell receptor expression. Knockdown and knockout of EFhd1 in 38B9 pro B cells decreased the oxidative phosphorylation/glycolysis (OCR/ECAR) ratio by increasing glycolysis, glycolytic capacity and reserve. Prolonged expression of EFhd1 in EFhd1 transgenic mice beyond the pro B cell stage increased expression of the mitochondrial co-activator PGC-1α in primary pre B cells, but reduced mitochondrial ATP production at the pro to pre B cell transition in IL-7 cultures. Transgenic EFhd1 expression caused a B-cell intrinsic developmental disadvantage for pro and pre B cells. Hence, coordinated expression of EFhd1 in pro B cells and by the pre BCR regulates metabolic changes and pro/pre B-cell development.
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Affiliation(s)
- Merle Stein
- Department of Internal Medicine 3, Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Sebastian Dütting
- Department of Internal Medicine 3, Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Dimitrios Mougiakakos
- Department of Internal Medicine V, University Clinic, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Michael Bösl
- Department of Experimental Biomedicine, University Hospital and Rudolf Virchow Center, University of Würzburg, Würzburg D-97080, Germany
| | - Kristin Fritsch
- Department of Internal Medicine 3, Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Dorothea Reimer
- Department of Internal Medicine 3, Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Sophia Urbanczyk
- Department of Internal Medicine 3, Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Tobit Steinmetz
- Department of Internal Medicine 3, Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Wolfgang Schuh
- Department of Internal Medicine 3, Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Aline Bozec
- Department of Internal Medicine III, University Clinic, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Thomas H Winkler
- Department of Biology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Hans-Martin Jäck
- Department of Internal Medicine 3, Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Dirk Mielenz
- Department of Internal Medicine 3, Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
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14
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Köhrer S, Havranek O, Seyfried F, Hurtz C, Coffey GP, Kim E, Hacken ET, Jäger U, Vanura K, O’Brien S, Thomas DA, Kantarjian H, Ghosh D, Wang Z, Zhang M, Ma W, Jumaa H, Debatin KM, Müschen M, Meyer LH, Davis RE, Burger JA. Pre-BCR signaling in precursor B-cell acute lymphoblastic leukemia regulates PI3K/AKT, FOXO1 and MYC, and can be targeted by SYK inhibition. Leukemia 2016; 30:1246-54. [PMID: 26847027 PMCID: PMC5459356 DOI: 10.1038/leu.2016.9] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 11/20/2015] [Accepted: 12/23/2015] [Indexed: 12/11/2022]
Abstract
Precursor-B-cell receptor (pre-BCR) signaling and spleen tyrosine kinase (SYK) recently were introduced as therapeutic targets for patients with B-cell acute lymphoblastic leukemia (B-ALL), but the importance of this pathway in B-ALL subsets and mechanism of downstream signaling have not fully been elucidated. Here, we provide new detailed insight into the mechanism of pre-BCR signaling in B-ALL. We compared the effects of pharmacological and genetic disruption of pre-BCR signaling in vitro and in mouse models for B-ALL, demonstrating exquisite dependency of pre-BCR(+) B-ALL, but not other B-ALL subsets, on this signaling pathway. We demonstrate that SYK, PI3K/AKT, FOXO1 and MYC are important downstream mediators of pre-BCR signaling in B-ALL. Furthermore, we define a characteristic immune phenotype and gene expression signature of pre-BCR(+) ALL to distinguish them from other B-ALL subsets. These data provide comprehensive new insight into pre-BCR signaling in B-ALL and corroborate pre-BCR signaling and SYK as promising new therapeutic targets in pre-BCR(+) B-ALL.
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Affiliation(s)
- Stefan Köhrer
- Department of Leukemia, Unit 428, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States, 77030
| | - Ondrej Havranek
- Department of Lymphoma/Myeloma, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States, 77030
| | - Felix Seyfried
- Ulm University Medical Center, Department of Pediatrics and Adolescent Medicine, Ulm, Germany
| | - Christian Hurtz
- Department of Laboratory Medicine, University of California, San Francisco, CA 94143
| | | | - Ekaterina Kim
- Department of Leukemia, Unit 428, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States, 77030
| | - Elisa ten Hacken
- Department of Leukemia, Unit 428, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States, 77030
| | - Ulrich Jäger
- Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna, Austria
| | - Katrina Vanura
- Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna, Austria
| | - Susan O’Brien
- Department of Leukemia, Unit 428, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States, 77030
| | - Deborah A. Thomas
- Department of Leukemia, Unit 428, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States, 77030
| | - Hagop Kantarjian
- Department of Leukemia, Unit 428, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States, 77030
| | - Dipanjan Ghosh
- Department of Lymphoma/Myeloma, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States, 77030
| | - Zhiqiang Wang
- Department of Lymphoma/Myeloma, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States, 77030
| | - Min Zhang
- Department of Lymphoma/Myeloma, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States, 77030
| | - Wencai Ma
- Department of Lymphoma/Myeloma, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States, 77030
| | - Hassan Jumaa
- Ulm University, Department of Immunology, Ulm, Germany
| | - Klaus-Michael Debatin
- Ulm University Medical Center, Department of Pediatrics and Adolescent Medicine, Ulm, Germany
| | - Markus Müschen
- Department of Laboratory Medicine, University of California, San Francisco, CA 94143
| | - Lüder H. Meyer
- Ulm University Medical Center, Department of Pediatrics and Adolescent Medicine, Ulm, Germany
| | - R. Eric Davis
- Department of Lymphoma/Myeloma, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States, 77030
| | - Jan A. Burger
- Department of Leukemia, Unit 428, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States, 77030
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15
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Shojaee S, Chan LN, Buchner M, Cazzaniga V, Cosgun KN, Geng H, Qiu YH, von Minden MD, Ernst T, Hochhaus A, Cazzaniga G, Melnick A, Kornblau SM, Graeber TG, Wu H, Jumaa H, Müschen M. PTEN opposes negative selection and enables oncogenic transformation of pre-B cells. Nat Med 2016; 22:379-87. [PMID: 26974310 PMCID: PMC5178869 DOI: 10.1038/nm.4062] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 02/10/2016] [Indexed: 11/08/2022]
Abstract
Phosphatase and tensin homolog (PTEN) is a negative regulator of the phosphatidylinositol 3-kinase (PI3K) and protein kinase B (AKT) signaling pathway and a potent tumor suppressor in many types of cancer. To test a tumor suppressive role for PTEN in pre-B acute lymphoblastic leukemia (ALL), we induced Cre-mediated deletion of Pten in mouse models of pre-B ALL. In contrast to its role as a tumor suppressor in other cancers, loss of one or both alleles of Pten caused rapid cell death of pre-B ALL cells and was sufficient to clear transplant recipient mice of leukemia. Small-molecule inhibition of PTEN in human pre-B ALL cells resulted in hyperactivation of AKT, activation of the p53 tumor suppressor cell cycle checkpoint and cell death. Loss of PTEN function in pre-B ALL cells was functionally equivalent to acute activation of autoreactive pre-B cell receptor signaling, which engaged a deletional checkpoint for the removal of autoreactive B cells. We propose that targeted inhibition of PTEN and hyperactivation of AKT triggers a checkpoint for the elimination of autoreactive B cells and represents a new strategy to overcome drug resistance in human ALL.
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Affiliation(s)
- Seyedmehdi Shojaee
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Lai N. Chan
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Maike Buchner
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Valeria Cazzaniga
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA
- Centro Ricerca Tettamanti, Clinica Pediatrica, Università di Milano-Bicocca, Ospedale S. Gerardo, Monza, Italy
| | - Kadriye Nehir Cosgun
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Huimin Geng
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Yi Hua Qiu
- Department of Leukemia, The University of Texas M.D. Anderson Cancer Center, Houston, TX, USA
| | | | - Thomas Ernst
- Abteilung Hämatologie/Onkologie, Klinik für Innere Medizin II, Universitätsklinikum Jena, Jena, Germany
| | - Andreas Hochhaus
- Abteilung Hämatologie/Onkologie, Klinik für Innere Medizin II, Universitätsklinikum Jena, Jena, Germany
| | - Giovanni Cazzaniga
- Centro Ricerca Tettamanti, Clinica Pediatrica, Università di Milano-Bicocca, Ospedale S. Gerardo, Monza, Italy
| | - Ari Melnick
- Department of Pharmacology, Weill Cornell Medical College, New York, NY, USA
| | - Steven M. Kornblau
- Department of Leukemia, The University of Texas M.D. Anderson Cancer Center, Houston, TX, USA
| | - Thomas G. Graeber
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA, USA
| | - Hong Wu
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA, USA
| | - Hassan Jumaa
- Department of Immunology, University of Ulm, Germany
| | - Markus Müschen
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA
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16
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De Grandis M, Lhoumeau AC, Mancini SJC, Aurrand-Lions M. Adhesion receptors involved in HSC and early-B cell interactions with bone marrow microenvironment. Cell Mol Life Sci 2016; 73:687-703. [PMID: 26495446 PMCID: PMC11108274 DOI: 10.1007/s00018-015-2064-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 09/16/2015] [Accepted: 10/08/2015] [Indexed: 02/06/2023]
Abstract
Hematopoiesis takes place in the bone marrow of adult mammals and is the process by which blood cells are replenished every day throughout life. Differentiation of hematopoietic cells occurs in a stepwise manner through intermediates of differentiation that could be phenotypically identified. This has allowed establishing hematopoietic cell classification with hematopoietic stem cells (HSCs) at the top of the hierarchy. HSCs are mostly quiescent and serve as a reservoir for maintenance of lifelong hematopoiesis. Over recent years, it has become increasingly clear that HSC quiescence is not only due to intrinsic properties, but is also mediated by cognate interactions between HSCs and surrounding cells within micro-anatomical sites called “niches”. This hematopoietic/stromal crosstalk model also applies to more mature progenitors such as B cell progenitors, which are thought to reside in distinct “niches”. This prompted many research teams to search for specific molecular mechanisms supporting leuko-stromal crosstalk in the bone marrow and acting at specific stage of differentiation to regulate hematopoietic homeostasis. Here, we review recent data on adhesion mechanisms involved in HSCs and B cell progenitors interactions with surrounding bone marrow stromal cells.
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Affiliation(s)
- Maria De Grandis
- Centre de Recherche en Cancérologie de Marseille, Institut Paoli-Calmettes, Inserm U1068, CNRS UMR7258, Aix-Marseille Université UM105, Marseille, France
| | - Anne-Catherine Lhoumeau
- Centre de Recherche en Cancérologie de Marseille, Institut Paoli-Calmettes, Inserm U1068, CNRS UMR7258, Aix-Marseille Université UM105, Marseille, France
| | - Stéphane J. C. Mancini
- Centre de Recherche en Cancérologie de Marseille, Institut Paoli-Calmettes, Inserm U1068, CNRS UMR7258, Aix-Marseille Université UM105, Marseille, France
| | - Michel Aurrand-Lions
- Centre de Recherche en Cancérologie de Marseille, Institut Paoli-Calmettes, Inserm U1068, CNRS UMR7258, Aix-Marseille Université UM105, Marseille, France
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17
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Tafesse FG, Rashidfarrokhi A, Schmidt FI, Freinkman E, Dougan S, Dougan M, Esteban A, Maruyama T, Strijbis K, Ploegh HL. Disruption of Sphingolipid Biosynthesis Blocks Phagocytosis of Candida albicans. PLoS Pathog 2015; 11:e1005188. [PMID: 26431038 PMCID: PMC4592247 DOI: 10.1371/journal.ppat.1005188] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 09/03/2015] [Indexed: 01/08/2023] Open
Abstract
The ability of phagocytes to clear pathogens is an essential attribute of the innate immune response. The role of signaling lipid molecules such as phosphoinositides is well established, but the role of membrane sphingolipids in phagocytosis is largely unknown. Using a genetic approach and small molecule inhibitors, we show that phagocytosis of Candida albicans requires an intact sphingolipid biosynthetic pathway. Blockade of serine-palmitoyltransferase (SPT) and ceramide synthase-enzymes involved in sphingolipid biosynthesis- by myriocin and fumonisin B1, respectively, impaired phagocytosis by phagocytes. We used CRISPR/Cas9-mediated genome editing to generate Sptlc2-deficient DC2.4 dendritic cells, which lack serine palmitoyl transferase activity. Sptlc2-/- DC2.4 cells exhibited a stark defect in phagocytosis, were unable to bind fungal particles and failed to form a normal phagocytic cup to engulf C. albicans. Supplementing the growth media with GM1, the major ganglioside present at the cell surface, restored phagocytic activity of Sptlc2-/- DC2.4 cells. While overall membrane trafficking and endocytic pathways remained functional, Sptlc2-/- DC2.4 cells express reduced levels of the pattern recognition receptors Dectin-1 and TLR2 at the cell surface. Consistent with the in vitro data, compromised sphingolipid biosynthesis in mice sensitizes the animal to C. albicans infection. Sphingolipid biosynthesis is therefore critical for phagocytosis and in vivo clearance of C. albicans. The fungus Candida albicans is not only a commensal of the digestive system, but also a common cause of human opportunistic infections. Macrophages and dendritic cells can eliminate C. albicans by phagocytosis, a complex process that involves extensive membrane reorganization at the cell surface. The extent to which membrane lipids, including sphingolipids, contribute to the proper execution of phagocytosis remains largely unknown. Pharmacological blockade of sphingolipid biosynthesis by the small molecule inhibitors myriocin and fumonisin B1 impairs phagocytosis of C. albicans. DC2.4 dendritic cells genetically deficient in Sptlc2, the enzyme that catalyzes the first and rate-limiting step in the sphingolipid biosynthetic pathway, are likewise defective in phagocytosis of C. albicans. Sptlc2-/- DC2.4 cells showed reduced binding of C. albicans, but overall membrane transport and protein secretion remained functional. Sptlc2-deficient cells express reduced levels of the receptors Dectin-1 and TLR2 at the cell surface, and are unable to form a normal phagocytic cup. Exogenous addition of the major ganglioside GM1 restored phagocytic ability of Sptlc2-/- DC2.4 cells. Mice with compromised sphingolipid production upon in vivo treatment with fumonisin B1 fail to eradicate C. albicans, consistent with the in vitro results. Sphingolipids are thus essential for clearance of fungal infection through phagocytosis, and hence indispensable for the proper functioning of the innate immune system.
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Affiliation(s)
- Fikadu G. Tafesse
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, United States of America
- * E-mail: ,
| | - Ali Rashidfarrokhi
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Florian I. Schmidt
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Elizaveta Freinkman
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Stephanie Dougan
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Michael Dougan
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Alexandre Esteban
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Takeshi Maruyama
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Karin Strijbis
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Hidde L. Ploegh
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
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18
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Cuajungco MP, Silva J, Habibi A, Valadez JA. The mucolipin-2 (TRPML2) ion channel: a tissue-specific protein crucial to normal cell function. Pflugers Arch 2015; 468:177-92. [PMID: 26336837 DOI: 10.1007/s00424-015-1732-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 08/25/2015] [Accepted: 08/27/2015] [Indexed: 12/26/2022]
Abstract
The discovery of the TRPML subfamily of ion channels has created an exciting niche in the fields of membrane trafficking, signal transduction, autophagy, and metal homeostasis. The TRPML protein subfamily consists of three members, TRPML1, TRPML2, and TRPML3, which are encoded by MCOLN1, MCOLN2, and MCOLN3 genes, respectively. They are non-selective cation channels with six predicted transmembrane domains and intracellular amino- and carboxyl-terminus regions. They localize to the plasma membrane, endosomes, and lysosomes of cells. TRPML1 is associated with the human lysosomal storage disease known as mucolipidosis type IV (MLIV), but TRPML2 and TRPML3 have not been linked with a human disease. Although TRPML1 is expressed in many tissues, TRPML3 is expressed in a varied but limited set of tissues, while TRPML2 has a more limited expression pattern where it is mostly detected in lymphoid and myeloid tissues. This review focuses on TRPML2 because it appears to play an important, yet unrecognized role in the immune system. While the evidence has been mostly indirect, we present and discuss relevant data that strengthen the connection of TRPML2 with cellular immunity. We also discuss the functional redundancy between the TRPML proteins, and how such features could be exploited as a potential therapeutic strategy for MLIV disease. We present evidence that TRPML2 expression may complement certain phenotypic alterations in MLIV cells and briefly examine the challenges of functional complementation. In conclusion, the function of TRPML2 still remains obscure, but emerging data show that it may serve a critical role in immune cell development and inflammatory responses.
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Affiliation(s)
- Math P Cuajungco
- Department of Biological Science, California State University Fullerton, 800 N. State College Blvd., Fullerton, CA, 92831, USA. .,Center for Applied Biotechnology Studies, California State University Fullerton, Fullerton, CA, 92831, USA.
| | - Joshua Silva
- Department of Biological Science, California State University Fullerton, 800 N. State College Blvd., Fullerton, CA, 92831, USA
| | - Ania Habibi
- Department of Biological Science, California State University Fullerton, 800 N. State College Blvd., Fullerton, CA, 92831, USA
| | - Jessica A Valadez
- Department of Biological Science, California State University Fullerton, 800 N. State College Blvd., Fullerton, CA, 92831, USA
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19
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Müschen M. Rationale for targeting the pre-B-cell receptor signaling pathway in acute lymphoblastic leukemia. Blood 2015; 125:3688-93. [PMID: 25878119 PMCID: PMC4463734 DOI: 10.1182/blood-2015-01-567842] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Accepted: 04/10/2015] [Indexed: 12/16/2022] Open
Abstract
Inhibitors of B-cell receptor (BCR) and pre-BCR signaling were successfully introduced into patient care for various subtypes of mature B-cell lymphoma (e.g., ibrutinib, idelalisib). Acute lymphoblastic leukemia (ALL) typically originates from pre-B cells that critically depend on survival signals emanating from a functional pre-BCR. However, whether patients with ALL benefit from treatment with (pre-) BCR inhibitors has not been explored. Recent data suggest that the pre-BCR functions as tumor suppressor in the majority of cases of human ALL. However, a distinct subset of human ALL is selectively sensitive to pre-BCR antagonists.
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Affiliation(s)
- Markus Müschen
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA
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20
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Geng H, Hurtz C, Lenz KB, Chen Z, Baumjohann D, Thompson S, Goloviznina NA, Chen WY, Huan J, LaTocha D, Ballabio E, Xiao G, Lee JW, Deucher A, Qi Z, Park E, Huang C, Nahar R, Kweon SM, Shojaee S, Chan LN, Yu J, Kornblau SM, Bijl JJ, Ye BH, Ansel KM, Paietta E, Melnick A, Hunger SP, Kurre P, Tyner JW, Loh ML, Roeder RG, Druker BJ, Burger JA, Milne TA, Chang BH, Müschen M. Self-enforcing feedback activation between BCL6 and pre-B cell receptor signaling defines a distinct subtype of acute lymphoblastic leukemia. Cancer Cell 2015; 27:409-25. [PMID: 25759025 PMCID: PMC4618684 DOI: 10.1016/j.ccell.2015.02.003] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 12/22/2014] [Accepted: 02/10/2015] [Indexed: 10/23/2022]
Abstract
Studying 830 pre-B ALL cases from four clinical trials, we found that human ALL can be divided into two fundamentally distinct subtypes based on pre-BCR function. While absent in the majority of ALL cases, tonic pre-BCR signaling was found in 112 cases (13.5%). In these cases, tonic pre-BCR signaling induced activation of BCL6, which in turn increased pre-BCR signaling output at the transcriptional level. Interestingly, inhibition of pre-BCR-related tyrosine kinases reduced constitutive BCL6 expression and selectively killed patient-derived pre-BCR(+) ALL cells. These findings identify a genetically and phenotypically distinct subset of human ALL that critically depends on tonic pre-BCR signaling. In vivo treatment studies suggested that pre-BCR tyrosine kinase inhibitors are useful for the treatment of patients with pre-BCR(+) ALL.
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Affiliation(s)
- Huimin Geng
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Christian Hurtz
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Kyle B Lenz
- Division of Pediatric Hematology and Oncology, Department of Pediatrics, Oregon Health & Science University, Portland, OR 97239, USA; Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Zhengshan Chen
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Dirk Baumjohann
- Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Sarah Thompson
- Division of Pediatric Hematology and Oncology, Department of Pediatrics, Oregon Health & Science University, Portland, OR 97239, USA; Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Natalya A Goloviznina
- Division of Pediatric Hematology and Oncology, Department of Pediatrics, Oregon Health & Science University, Portland, OR 97239, USA; Papé Family Pediatric Research Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Wei-Yi Chen
- Laboratory of Biochemistry and Molecular Biology, Rockefeller University, New York, NY 10065, USA; Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei 11221, Taiwan
| | - Jianya Huan
- Division of Pediatric Hematology and Oncology, Department of Pediatrics, Oregon Health & Science University, Portland, OR 97239, USA; Papé Family Pediatric Research Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Dorian LaTocha
- Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Erica Ballabio
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Gang Xiao
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Jae-Woong Lee
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Anne Deucher
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Zhongxia Qi
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Eugene Park
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Chuanxin Huang
- Departments of Medicine and Pharmacology, Weill Cornell Medical College, New York, NY 10065, USA
| | - Rahul Nahar
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Soo-Mi Kweon
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Seyedmehdi Shojaee
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Lai N Chan
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Jingwei Yu
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Steven M Kornblau
- Department of Leukemia, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Janetta J Bijl
- Hôpital Maisonneuve-Rosemont, Montreal, QC H1T 2M4, Canada
| | - B Hilda Ye
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - K Mark Ansel
- Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Elisabeth Paietta
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Ari Melnick
- Departments of Medicine and Pharmacology, Weill Cornell Medical College, New York, NY 10065, USA
| | - Stephen P Hunger
- Division of Pediatric Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Peter Kurre
- Division of Pediatric Hematology and Oncology, Department of Pediatrics, Oregon Health & Science University, Portland, OR 97239, USA; Papé Family Pediatric Research Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Jeffrey W Tyner
- Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA; Department of Cell & Developmental Biology, Oregon Health & Science University, Portland, OR 97239, USA
| | - Mignon L Loh
- Pediatric Hematology-Oncology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Robert G Roeder
- Laboratory of Biochemistry and Molecular Biology, Rockefeller University, New York, NY 10065, USA
| | - Brian J Druker
- Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA; Howard Hughes Medical Institute, Portland, OR 97239, USA
| | - Jan A Burger
- Department of Leukemia, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Thomas A Milne
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Bill H Chang
- Division of Pediatric Hematology and Oncology, Department of Pediatrics, Oregon Health & Science University, Portland, OR 97239, USA; Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Markus Müschen
- Departments of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA.
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21
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Guendel I, Iordanskiy S, Sampey GC, Van Duyne R, Calvert V, Petricoin E, Saifuddin M, Kehn-Hall K, Kashanchi F. Role of Bruton's tyrosine kinase inhibitors in HIV-1-infected cells. J Neurovirol 2015; 21:257-75. [PMID: 25672887 DOI: 10.1007/s13365-015-0323-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 01/23/2015] [Indexed: 11/26/2022]
Abstract
Many cellular cofactors have been documented to be critical for various stages of viral replication. Using high-throughput proteomic assays, we have previously identified Bruton's tyrosine kinase (BTK) as a host protein that was uniquely upregulated in the plasma membrane of human immunodeficiency virus (HIV-1)-infected T cells. Here, we have further characterized the BTK expression in HIV-1 infection and show that this cellular factor is specifically expressed in infected myeloid cells. Significant upregulation of the phosphorylated form of BTK was observed in infected cells. Using size exclusion chromatography, we found BTK to be virtually absent in the uninfected U937 cells; however, new BTK protein complexes were identified and distributed in both high molecular weight (∼600 kDa) and a small molecular weight complex (∼60-120 kDa) in the infected U1 cells. BTK levels were highest in cells either chronically expressing virus or induced/infected myeloid cells and that BTK translocated to the membrane following induction of the infected cells. BTK knockdown in HIV-1-infected cells using small interfering RNA (siRNA) resulted in selective death of infected, but not uninfected, cells. Using BTK-specific antibody and small-molecule inhibitors including LFM-A13 and a FDA-approved compound, ibrutinib (PCI-32765), we have found that HIV-1-infected cells are sensitive to apoptotic cell death and result in a decrease in virus production. Overall, our data suggests that HIV-1-infected cells are sensitive to treatments targeting BTK expressed in infected cells.
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Affiliation(s)
- Irene Guendel
- Department of Systems Biology, National Center for Biodefense and Infectious Diseases, George Mason University, Manassas, VA, 20110, USA
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Abstract
During early stages of development, precursor B lymphocytes express a characteristic type of antigen receptor known as the pre-B-cell receptor (pre-BCR). This receptor differs from conventional BCRs in that it possesses a germ line-encoded surrogate light chain (SLC), which is associated with the signal transduction machinery via heavy chain (HC) proteins that have been generated by productive rearrangement of the immunoglobulin HC genes. The pre-BCR marks a key step of B-cell commitment, as it activates the B-cell-specific signaling cascade and mediates the selection, expansion, and differentiation of cells expressing a productively rearranged HC protein. Another difference between the pre-BCR and conventional BCR might be the initial event that triggers receptor activation, as the pre-BCR is activated in the absence of external ligands, while conventional BCRs require antigen for activation. Nonetheless, the pre-BCR downstream signaling cascade is largely similar to that of the BCR suggesting that the characteristic LC of the pre-BCR mediates important receptor interactions thereby providing distinctive, germ line-encoded features to the pre-BCR. In fact, the SLC enables the pre-BCR to act as a surrogate autoreactive receptor. Here, we outline the structure and function of the pre-BCR and how the autonomous signaling capacity might be a direct consequence of pre-BCR assembly. In addition to its role in early B-cell development, we discuss how the ordered activation of downstream signaling cascades enables the pre-BCR to activate seemingly opposing cellular programs such as proliferation and differentiation.
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23
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Corneth OBJ, Klein Wolterink RGJ, Hendriks RW. BTK Signaling in B Cell Differentiation and Autoimmunity. Curr Top Microbiol Immunol 2015; 393:67-105. [PMID: 26341110 DOI: 10.1007/82_2015_478] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Since the original identification of Bruton's tyrosine kinase (BTK) as the gene defective in the primary immunodeficiency X-linked agammaglobulinemia (XLA) in 1993, our knowledge on the physiological function of BTK has expanded impressively. In this review, we focus on the role of BTK during B cell differentiation in vivo, both in the regulation of expansion and in the developmental progression of pre-B cells in the bone marrow and as a crucial signal transducer of signals downstream of the IgM or IgG B cell antigen receptor (BCR) in mature B cells governing proliferation, survival, and differentiation. In particular, we highlight BTK function in B cells in the context of host defense and autoimmunity. Small-molecule inhibitors of BTK have very recently shown impressive anti-tumor activity in clinical studies in patients with various B cell malignancies. Since promising effects of BTK inhibition were also seen in experimental animal models for lupus and rheumatoid arthritis, BTK may be a good target for controlling autoreactive B cells in patients with systemic autoimmune disease.
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Affiliation(s)
- Odilia B J Corneth
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Room Ee2251a, PO Box 2040, NL 3000, CA, Rotterdam, The Netherlands
| | - Roel G J Klein Wolterink
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Room Ee2251a, PO Box 2040, NL 3000, CA, Rotterdam, The Netherlands
| | - Rudi W Hendriks
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Room Ee2251a, PO Box 2040, NL 3000, CA, Rotterdam, The Netherlands.
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24
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Santos-Argumedo L, Maravillas-Montero JL, López-Ortega O. Class I myosins in B-cell physiology: functions in spreading, immune synapses, motility, and vesicular traffic. Immunol Rev 2014; 256:190-202. [PMID: 24117822 DOI: 10.1111/imr.12105] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Myosins comprise a family of motor proteins whose role in muscle contraction and motility in a large range of eukaryotic cells has been widely studied. Although these proteins have been characterized extensively and much is known about their function in different cellular compartments, little is known about these molecules in hematopoietic cells. Myosins expressed by cells from the immune response are involved in maintaining plasma membrane tension, moving and secreting vesicles, endo- and exocytotic processes, and promoting the adhesion and motility of cells. Herein, we summarize our current understanding of class I myosins in B cells, with an emphasis on the emerging roles of these molecular motors in immune functions.
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25
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Abstract
Bruton's tyrosine kinase (BTK) is a key component of B cell receptor (BCR) signalling and functions as an important regulator of cell proliferation and cell survival in various B cell malignancies. Small-molecule inhibitors of BTK have shown antitumour activity in animal models and, recently, in clinical studies. High response rates were reported in patients with chronic lymphocytic leukaemia and mantle cell lymphoma. Remarkably, BTK inhibitors have molecular effects that cannot be explained by the classic role of BTK in BCR signalling. In this Review, we highlight the importance of BTK in various signalling pathways in the context of its therapeutic inhibition.
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Affiliation(s)
- Rudi W Hendriks
- Department of Pulmonary Medicine, Room Ee2251a, Erasmus MC Rotterdam, PO Box 2040, NL 3000 CA Rotterdam, the Netherlands
| | - Saravanan Yuvaraj
- Department of Pulmonary Medicine, Room Ee2251a, Erasmus MC Rotterdam, PO Box 2040, NL 3000 CA Rotterdam, the Netherlands
| | - Laurens P Kil
- Department of Pulmonary Medicine, Room Ee2251a, Erasmus MC Rotterdam, PO Box 2040, NL 3000 CA Rotterdam, the Netherlands
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26
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Anbazhagan K, Rabbind Singh A, Isabelle P, Stella I, Céline ADM, Bissac E, Bertrand B, Rémy N, Naomi T, Vincent F, Rochette J, Lassoued K. Human pre-B cell receptor signal transduction: evidence for distinct roles of PI3kinase and MAP-kinase signalling pathways. IMMUNITY INFLAMMATION AND DISEASE 2013; 1:26-36. [PMID: 25400915 PMCID: PMC4217539 DOI: 10.1002/iid3.4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 07/08/2013] [Accepted: 07/11/2013] [Indexed: 12/16/2022]
Abstract
Pre-BCR acts as a critical checkpoint in B cell development. However, its signalling cascade still remains indistinctly characterised in human. We investigated pre-BCR signalling pathway to examine its regulation in normal primary pre-B lymphocytes and pre-B cell lines. In cell lines, early signalling events occurring after pre-BCR stimulation include phosphorylation of Lyn, Blk and Syk together with ZAP70, Btk, Vav, PLC-γ2 and various adaptor proteins, such as BLNK, LAB, LAT and SLP-76. Further downstream, these molecules induced activation of the PI3K/AKT and MAP-kinase resulting in an augmentation of canonical NF-κB pathways and cFos/AP1 activation. PI3K and MAPK exerted opposing effects on the pre-BCR-induced activation of the canonical NF-κB and c-Fos/AP1 pathways. Immediate nuclear export of FoxO3A and delayed import of IRF4 were additional events observed after pre-BCR crosslinking in primary cells. Pre-BCR-induced down-regulation of Rag1, Rag2, E2A and Pax5 transcripts occurred in a PI3K-dependent manner. Finally we bring evidence that pre-BCR stimulation or co stimulation with CD19 enhances cell cycle signal.
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Affiliation(s)
- Kolandaswamy Anbazhagan
- Inserm/UMR925, Université Picardie Jules Verne, Laboratoire d'Immunologie, UFR de Médecine 3, rue des Louvels, 80036, Amiens, France
| | - Amrathlal Rabbind Singh
- Inserm/UMR925, Université Picardie Jules Verne, Laboratoire d'Immunologie, UFR de Médecine 3, rue des Louvels, 80036, Amiens, France
| | - Piec Isabelle
- Inserm/UMR925, Université Picardie Jules Verne, Laboratoire d'Immunologie, UFR de Médecine 3, rue des Louvels, 80036, Amiens, France
| | - Ibata Stella
- Inserm/UMR925, Université Picardie Jules Verne, Laboratoire d'Immunologie, UFR de Médecine 3, rue des Louvels, 80036, Amiens, France
| | - Alleaume-De Martel Céline
- Inserm/UMR925, Université Picardie Jules Verne, Laboratoire d'Immunologie, UFR de Médecine 3, rue des Louvels, 80036, Amiens, France
| | - Eliane Bissac
- Inserm/UMR925, Université Picardie Jules Verne, Laboratoire d'Immunologie, UFR de Médecine 3, rue des Louvels, 80036, Amiens, France
| | - Brassart Bertrand
- Inserm/UMR925, Université Picardie Jules Verne, Laboratoire d'Immunologie, UFR de Médecine 3, rue des Louvels, 80036, Amiens, France
| | - Nyga Rémy
- Inserm/UMR925, Université Picardie Jules Verne, Laboratoire d'Immunologie, UFR de Médecine 3, rue des Louvels, 80036, Amiens, France
| | - Taylor Naomi
- CNRS/UMR 5535, Institut de Génétique Moléculaire de Montpellier 1919 Route de Mende, 34293, Montpellier, Cedex 5, France
| | - Fuentes Vincent
- Inserm/UMR925, Université Picardie Jules Verne, Laboratoire d'Immunologie, UFR de Médecine 3, rue des Louvels, 80036, Amiens, France
| | - Jacques Rochette
- Inserm/UMR925, Université Picardie Jules Verne, Laboratoire d'Immunologie, UFR de Médecine 3, rue des Louvels, 80036, Amiens, France
| | - Kaïss Lassoued
- Inserm/UMR925, Université Picardie Jules Verne, Laboratoire d'Immunologie, UFR de Médecine 3, rue des Louvels, 80036, Amiens, France
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Hauser J, Verma-Gaur J, Grundström T. Broad feedback inhibition of pre-B-cell receptor signaling components. Mol Immunol 2013; 54:247-53. [DOI: 10.1016/j.molimm.2012.12.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Revised: 11/28/2012] [Accepted: 12/04/2012] [Indexed: 11/13/2022]
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Casanova JL, Abel L. The genetic theory of infectious diseases: a brief history and selected illustrations. Annu Rev Genomics Hum Genet 2013; 14:215-43. [PMID: 23724903 PMCID: PMC4980761 DOI: 10.1146/annurev-genom-091212-153448] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Until the mid-nineteenth century, life expectancy at birth averaged 20 years worldwide, owing mostly to childhood fevers. The germ theory of diseases then gradually overcame the belief that diseases were intrinsic. However, around the turn of the twentieth century, asymptomatic infection was discovered to be much more common than clinical disease. Paradoxically, this observation barely challenged the newly developed notion that infectious diseases were fundamentally extrinsic. Moreover, interindividual variability in the course of infection was typically explained by the emerging immunological (or somatic) theory of infectious diseases, best illustrated by the impact of vaccination. This powerful explanation is, however, best applicable to reactivation and secondary infections, particularly in adults; it can less easily account for interindividual variability in the course of primary infection during childhood. Population and clinical geneticists soon proposed a complementary hypothesis, a germline genetic theory of infectious diseases. Over the past century, this idea has gained some support, particularly among clinicians and geneticists, but has also encountered resistance, particularly among microbiologists and immunologists. We present here the genetic theory of infectious diseases and briefly discuss its history and the challenges encountered during its emergence in the context of the apparently competing but actually complementary microbiological and immunological theories. We also illustrate its recent achievements by highlighting inborn errors of immunity underlying eight life-threatening infectious diseases of children and young adults. Finally, we consider the far-reaching biological and clinical implications of the ongoing human genetic dissection of severe infectious diseases.
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Affiliation(s)
- Jean-Laurent Casanova
- St. Giles Laboratory of Human Genetics of Infectious Diseases, Rockefeller Branch, The Rockefeller University, New York, NY 10065;
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29
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Benichou J, Glanville J, Prak ETL, Azran R, Kuo TC, Pons J, Desmarais C, Tsaban L, Louzoun Y. The restricted DH gene reading frame usage in the expressed human antibody repertoire is selected based upon its amino acid content. THE JOURNAL OF IMMUNOLOGY 2013; 190:5567-77. [PMID: 23630353 DOI: 10.4049/jimmunol.1201929] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The Ab repertoire is not uniform. Some variable, diversity, and joining genes are used more frequently than others. Nonuniform usage can result from the rearrangement process, or from selection. To study how the Ab repertoire is selected, we analyzed one part of diversity generation that cannot be driven by the rearrangement mechanism: the reading frame usage of DH genes. We have used two high-throughput sequencing methodologies, multiple subjects and advanced algorithms to measure the DH reading frame usage in the human Ab repertoire. In most DH genes, a single reading frame is used predominantly, and inverted reading frames are practically never observed. The choice of a single DH reading frame is not limited to a single position of the DH gene. Rather, each DH gene participates in rearrangements of differing CDR3 lengths, restricted to multiples of three. In nonproductive rearrangements, there is practically no reading frame bias, but there is still a striking absence of inversions. Biases in DH reading frame usage are more pronounced, but also exhibit greater interindividual variation, in IgG(+) and IgA(+) than in IgM(+) B cells. These results suggest that there are two developmental checkpoints of DH reading frame selection. The first occurs during VDJ recombination, when inverted DH genes are usually avoided. The second checkpoint occurs after rearrangement, once the BCR is expressed. The second checkpoint implies that DH reading frames are subjected to differential selection. Following these checkpoints, clonal selection induces a host-specific DH reading frame usage bias.
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Affiliation(s)
- Jennifer Benichou
- Mina and Everard Goodman Faculty of Life Sciences, Bar Ilan University, Ramat Gan 52900, Israel
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30
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Pieper K, Grimbacher B, Eibel H. B-cell biology and development. J Allergy Clin Immunol 2013; 131:959-71. [PMID: 23465663 DOI: 10.1016/j.jaci.2013.01.046] [Citation(s) in RCA: 315] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 01/21/2013] [Accepted: 01/22/2013] [Indexed: 02/06/2023]
Abstract
B cells develop from hematopoietic precursor cells in an ordered maturation and selection process. Extensive studies with many different mouse mutants provided fundamental insights into this process. However, the characterization of genetic defects causing primary immunodeficiencies was essential in understanding human B-cell biology. Defects in pre-B-cell receptor components or in downstream signaling proteins, such as Bruton tyrosine kinase and B-cell linker protein, arrest development at the pre-B-cell stage. Defects in survival-regulating proteins, such as B-cell activator of the TNF-α family receptor (BAFF-R) or caspase recruitment domain-containing protein 11 (CARD11), interrupt maturation and prevent differentiation of transitional B cells into marginal zone and follicular B cells. Mature B-cell subsets, immune responses, and memory B-cell and plasma cell development are disturbed by mutations affecting Toll-like receptor signaling, B-cell antigen receptor coreceptors (eg, CD19), or enzymes responsible for immunoglobulin class-switch recombination. Transgenic mouse models helped to identify key regulatory mechanisms, such as receptor editing and clonal anergy, preventing the activation of B cells expressing antibodies recognizing autoantigens. Nevertheless, the combination of susceptible genetic backgrounds with the rescue of self-reactive B cells by T cells allows the generation of autoreactive clones found in patients with many autoimmune diseases and even in those with primary immunodeficiencies. The rapid progress of functional genomic research is expected to foster the development of new tools that specifically target dysfunctional B lymphocytes to treat autoimmunity, B-cell malignancies, and immunodeficiency.
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Affiliation(s)
- Kathrin Pieper
- Centre of Chronic Immunodeficiency, University Medical Centre Freiburg, Faculty of Biology, Albert-Ludwigs-Universität, Freiburg, Germany
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31
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Conley ME, Dobbs AK, Quintana AM, Bosompem A, Wang YD, Coustan-Smith E, Smith AM, Perez EE, Murray PJ. Agammaglobulinemia and absent B lineage cells in a patient lacking the p85α subunit of PI3K. J Exp Med 2012; 209:463-70. [PMID: 22351933 PMCID: PMC3302225 DOI: 10.1084/jem.20112533] [Citation(s) in RCA: 145] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Accepted: 01/27/2012] [Indexed: 12/17/2022] Open
Abstract
Whole exome sequencing was used to determine the causative gene in patients with B cell defects of unknown etiology. A homozygous premature stop codon in exon 6 of PIK3R1 was identified in a young woman with colitis and absent B cells. The mutation results in the absence of p85α but normal expression of the p50α and p55α regulatory subunits of PI3K. Bone marrow aspirates from the patient showed <0.1% CD19(+) B cells with normal percentages of TdT(+)VpreB(+)CD19(-) B cell precursors. This developmental block is earlier than that seen in patients with defects in the B cell receptor signaling pathway or in a strain of engineered mice with a similar defect in p85α. The number and function of the patient's T cells were normal. However, Western blot showed markedly decreased p110δ, as well as absent p85α, in patient T cells, neutrophils, and dendritic cells. The patient had normal growth and development and normal fasting glucose and insulin. Mice with p85α deficiency have insulin hypersensitivity, defective platelet function, and abnormal mast cell development. In contrast, the absence of p85α in the patient results in an early and severe defect in B cell development but minimal findings in other organ systems.
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Affiliation(s)
- Mary Ellen Conley
- Department of Pediatrics, University of Tennessee College of Medicine, Memphis, TN 38163, USA.
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Ficarro SB, Zhang Y, Carrasco-Alfonso MJ, Garg B, Adelmant G, Webber JT, Luckey CJ, Marto JA. Online nanoflow multidimensional fractionation for high efficiency phosphopeptide analysis. Mol Cell Proteomics 2011; 10:O111.011064. [PMID: 21788404 PMCID: PMC3226414 DOI: 10.1074/mcp.o111.011064] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 07/22/2011] [Indexed: 02/01/2023] Open
Abstract
Despite intense, continued interest in global analyses of signaling cascades through mass spectrometry-based studies, the large-scale, systematic production of phosphoproteomics data has been hampered in-part by inefficient fractionation strategies subsequent to phosphopeptide enrichment. Here we explore two novel multidimensional fractionation strategies for analysis of phosphopeptides. In the first technique we utilize aliphatic ion pairing agents to improve retention of phosphopeptides at high pH in the first dimension of a two-dimensional RP-RP. The second approach is based on the addition of strong anion exchange as the second dimension in a three-dimensional reversed phase (RP)-strong anion exchange (SAX)-RP configuration. Both techniques provide for automated, online data acquisition, with the 3-D platform providing the highest performance both in terms of separation peak capacity and the number of unique phosphopeptide sequences identified per μg of cell lysate consumed. Our integrated RP-SAX-RP platform provides several analytical figures of merit, including: (1) orthogonal separation mechanisms in each dimension; (2) high separation peak capacity (3) efficient retention of singly- and multiply-phosphorylated peptides; (4) compatibility with automated, online LC-MS analysis. We demonstrate the reproducibility of RP-SAX-RP and apply it to the analysis of phosphopeptides derived from multiple biological contexts, including an in vitro model of acute myeloid leukemia in addition to primary polyclonal CD8(+) T-cells activated in vivo through bacterial infection and then purified from a single mouse.
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Affiliation(s)
- Scott B. Ficarro
- From the ‡Department of Cancer Biology and Blais Proteomics Center, Dana-Farber Cancer Institute
- §Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School
| | - Yi Zhang
- From the ‡Department of Cancer Biology and Blais Proteomics Center, Dana-Farber Cancer Institute
- §Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School
| | | | - Brijesh Garg
- From the ‡Department of Cancer Biology and Blais Proteomics Center, Dana-Farber Cancer Institute
| | - Guillaume Adelmant
- From the ‡Department of Cancer Biology and Blais Proteomics Center, Dana-Farber Cancer Institute
- §Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School
| | - James T. Webber
- From the ‡Department of Cancer Biology and Blais Proteomics Center, Dana-Farber Cancer Institute
| | - C. John Luckey
- ¶Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115-6084
| | - Jarrod A. Marto
- From the ‡Department of Cancer Biology and Blais Proteomics Center, Dana-Farber Cancer Institute
- §Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School
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Hendriks RW, Bredius RG, Pike-Overzet K, Staal FJ. Biology and novel treatment options for XLA, the most common monogenetic immunodeficiency in man. Expert Opin Ther Targets 2011; 15:1003-21. [PMID: 21635151 DOI: 10.1517/14728222.2011.585971] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION X-linked agammaglobulinemia (XLA) is the most common primary immunodeficiency in man, and is caused by a single genetic defect. Inactivating mutations in the Bruton's tyrosine kinase (BTK) gene are invariably the cause of XLA,. XLA is characterized by a differentiation arrest at the pre-B cell stage, the absence of immunoglobulins and recurrent bacterial infections, making it an insidious disease that gradually disables the patient, and can result in death due to chronic lung disease. Current treatment involves prophylactic antibiotics and immunoglobulin infusions, which are non-curative. This disease is a good candidate for curative hematopoietic stem cell (HSC)-based gene therapy, which could correct the B cell and myeloid deficiencies. AREAS COVERED This paper reviews the basic biology of BTK in B cell development, the clinical features of XLA, and the possibilities of gene therapy for XLA, covering the literature from 1995 to 2010. EXPERT OPINION Work from various laboratories demonstrates the feasibility of using gene-corrected HSCs to complement the immune defects of Btk-deficiency in mice. We propose that it is timely to start clinical programs to develop stem cell based therapy for XLA, using gene-corrected autologous HSC.
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Affiliation(s)
- Rudi W Hendriks
- Department of Pulmonary Medicine, Erasmus MC, Rotterdam, The Netherlands
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The P4-type ATPase ATP11C is essential for B lymphopoiesis in adult bone marrow. Nat Immunol 2011; 12:434-40. [PMID: 21423172 PMCID: PMC3079768 DOI: 10.1038/ni.2012] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Accepted: 02/23/2011] [Indexed: 02/06/2023]
Abstract
B lymphopoiesis begins in fetal liver, switching to bone marrow after birth where it persists for life. The unique developmental outcomes of each phase are well documented, yet their molecular requirements are not. Here we describe two allelic X-linked mutations in mice that caused a cell-intrinsic arrest of adult B lymphopoiesis. Mutant fetal liver progenitors generated B cells in situ, but not in irradiated adult bone marrow, highlighting a necessity for the affected pathway only in the context of adult bone marrow. The causative mutation was ascribed to Atp11c, which encodes a P4-type ATPase with no previously described function. Our data establish an essential, cell-autonomous and context-sensitive function for ATP11C, a putative aminophospholipid flippase, in B cell development.
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Gupta P, Vijayan VK, Bansal SK. Sphingomyelin metabolism in erythrocyte membrane in asthma. J Asthma 2010; 47:966-71. [PMID: 21054235 DOI: 10.1080/02770903.2010.517590] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Sphingomyelin (SM), a major lipid constituent of outer leaflet of plasma membranes, with cholesterol, constitutes microdomains, which are termed as lipid rafts. These rafts provide support to proteins, receptors, enzymes, and so on and organize and orient them to conduct cellular functions including transmembrane signaling to substances in external milieu. The SM contents are regulated by its metabolism, changes in which may affect the composition of lipid rafts and cell response to the triggers of asthma which may lead to the pathophysiology. For studying changes in membranes, erythrocytes, which contain lipid rafts, are considered to be the best cell type. Hence, this study was conducted on plasma membrane of erythrocytes of asthmatic patients. OBJECTIVE The objective is to understand the changes in SM metabolism in asthma. METHODS The study included 50 subjects (25 asthmatics and 25 healthy subjects). Erythrocytes were isolated from the peripheral blood and membrane prepared. This was followed by determination of total cholesterol, phospholipids, SM, and sphingomyelinase activity. P < .05 was considered significant. RESULTS AND CONCLUSIONS In asthmatics, there was a significant decrease in cholesterol contents (p < .05), decrease in total phospholipid contents (p < .005), increase in SM (p < .01), decrease in cholesterol: SM ratio (p < .001) and increase in sphingomyelinase activity (p < .001) in erythrocyte membranes. We conclude that in asthma, the increase in SM contents is associated with increased sphingomyelinase activity which shows an imbalance in SM metabolism, directed toward its accumulation. The ratio of cholesterol to SM, critical for maintenance of lipid rafts, was significantly lower in asthmatics. This indicates changes in structure of lipid rafts which may lead to the pathophysiology and development of asthma. Regulation of SM metabolism may help in disease regulation and its control.
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Affiliation(s)
- Prachi Gupta
- Department of Biochemistry, V. P. Chest Institute, University of Delhi, Delhi, India
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Treanor B, Batista FD. Organisation and dynamics of antigen receptors: implications for lymphocyte signalling. Curr Opin Immunol 2010; 22:299-307. [DOI: 10.1016/j.coi.2010.03.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 03/23/2010] [Accepted: 03/26/2010] [Indexed: 10/19/2022]
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E-selectin engages PSGL-1 and CD44 through a common signaling pathway to induce integrin alphaLbeta2-mediated slow leukocyte rolling. Blood 2010; 116:485-94. [PMID: 20299514 DOI: 10.1182/blood-2009-12-259556] [Citation(s) in RCA: 156] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
In inflamed venules, neutrophils rolling on E-selectin induce integrin alpha(L)beta(2)-dependent slow rolling on intercellular adhesion molecule-1 by activating Src family kinases (SFKs), DAP12 and Fc receptor-gamma (FcRgamma), spleen tyrosine kinase (Syk), and p38. E-selectin signaling cooperates with chemokine signaling to recruit neutrophils into tissues. Previous studies identified P-selectin glycoprotein ligand-1 (PSGL-1) as the essential E-selectin ligand and Fgr as the only SFK that initiate signaling to slow rolling. In contrast, we found that E-selectin engagement of PSGL-1 or CD44 triggered slow rolling through a common, lipid raft-dependent pathway that used the SFKs Hck and Lyn as well as Fgr. We identified the Tec kinase Bruton tyrosine kinase as a key signaling intermediate between Syk and p38. E-selectin engagement of PSGL-1 was dependent on its cytoplasmic domain to activate SFKs and slow rolling. Although recruiting phosphoinositide-3-kinase to the PSGL-1 cytoplasmic domain was reported to activate integrins, E-selectin-mediated slow rolling did not require phosphoinositide-3-kinase. Studies in mice confirmed the physiologic significance of these events for neutrophil slow rolling and recruitment during inflammation. Thus, E-selectin triggers common signals through distinct neutrophil glycoproteins to induce alpha(L)beta(2)-dependent slow rolling.
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Calmodulin inhibition of E2A stops expression of surrogate light chains of the pre-B-cell receptor and CD19. Mol Immunol 2010; 47:1031-8. [DOI: 10.1016/j.molimm.2009.11.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Revised: 11/10/2009] [Accepted: 11/13/2009] [Indexed: 01/03/2023]
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Nahar R, Müschen M. Pre-B cell receptor signaling in acute lymphoblastic leukemia. Cell Cycle 2009; 8:3874-7. [PMID: 19901533 DOI: 10.4161/cc.8.23.10035] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
B cell lineage ALL represents by far the most frequent malignancy in children and is also common in adults. Despite significant advances over the past four decades, cytotoxic treatment strategies have recently reached a plateau with cure rates at 80 percent for children and 55 percent for adults. Relapse after cytotoxic drug treatment, initial drug-resistance and dose-limiting toxicity are among the most frequent complications of current therapy approaches. For this reason, pathway-specific treatment strategies in addition to cytotoxic drug treatment seem promising to further improve therapy options for ALL patients. In a recent study on 111 cases of pre-B cell-derived human ALL, we found that ALL cells carrying a BCR-ABL1-gene rearrangement lack expression of a functional pre-B cell receptor in virtually all cases. In a proof-of-principle experiment, we studied pre-B cell receptor function during progressive leukemic transformation of pre-B cells in BCR-ABL1-transgenic mice: Interestingly, signaling from the pre-B cell receptor and the oncogenic BCR-ABL1 kinase are mutually exclusive and only "crippled" pre-B cells that fail to express a functional pre-B cell receptor are permissive to transformation by BCR-ABL1.
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Affiliation(s)
- Rahul Nahar
- Leukemia and Lymphoma Program, USC Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, USA
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40
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Trageser D, Iacobucci I, Nahar R, Duy C, von Levetzow G, Klemm L, Park E, Schuh W, Gruber T, Herzog S, Kim YM, Hofmann WK, Li A, Storlazzi CT, Jäck HM, Groffen J, Martinelli G, Heisterkamp N, Jumaa H, Müschen M. Pre-B cell receptor-mediated cell cycle arrest in Philadelphia chromosome-positive acute lymphoblastic leukemia requires IKAROS function. ACTA ACUST UNITED AC 2009; 206:1739-53. [PMID: 19620627 PMCID: PMC2722172 DOI: 10.1084/jem.20090004] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
B cell lineage acute lymphoblastic leukemia (ALL) arises in virtually all cases from B cell precursors that are arrested at pre–B cell receptor–dependent stages. The Philadelphia chromosome–positive (Ph+) subtype of ALL accounts for 25–30% of cases of adult ALL, has the most unfavorable clinical outcome among all ALL subtypes and is defined by the oncogenic BCR-ABL1 kinase and deletions of the IKAROS gene in >80% of cases. Here, we demonstrate that the pre–B cell receptor functions as a tumor suppressor upstream of IKAROS through induction of cell cycle arrest in Ph+ ALL cells. Pre–B cell receptor–mediated cell cycle arrest in Ph+ ALL cells critically depends on IKAROS function, and is reversed by coexpression of the dominant-negative IKAROS splice variant IK6. IKAROS also promotes tumor suppression through cooperation with downstream molecules of the pre–B cell receptor signaling pathway, even if expression of the pre–B cell receptor itself is compromised. In this case, IKAROS redirects oncogenic BCR-ABL1 tyrosine kinase signaling from SRC kinase-activation to SLP65, which functions as a critical tumor suppressor downstream of the pre–B cell receptor. These findings provide a rationale for the surprisingly high frequency of IKAROS deletions in Ph+ ALL and identify IKAROS-mediated cell cycle exit as the endpoint of an emerging pathway of pre–B cell receptor–mediated tumor suppression.
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Affiliation(s)
- Daniel Trageser
- Leukemia and Lymphoma Program, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90027, USA
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Xu S, Huo J, Gunawan M, Su IH, Lam KP. Activated dectin-1 localizes to lipid raft microdomains for signaling and activation of phagocytosis and cytokine production in dendritic cells. J Biol Chem 2009; 284:22005-22011. [PMID: 19525229 DOI: 10.1074/jbc.m109.009076] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Lipid rafts are plasma membrane microdomains that are enriched in cholesterol, glycosphingolipids, and glycosylphosphatidylinositol-anchored proteins and play an important role in the signaling of ITAM-bearing lymphocyte antigen receptors. Dectin-1 is a C-type lectin receptor (CLR) that recognizes beta-glucan in the cell walls of fungi and triggers signal transduction via its cytoplasmic hemi-ITAM. However, it is not known if similar to antigen receptors, Dectin-1 would also signal via lipid rafts and if the integrity of lipid raft microdomains is important for the physiological functions mediated by Dectin-1. We demonstrate here using sucrose gradient ultracentrifugation and confocal microscopy that Dectin-1 translocates to lipid rafts upon stimulation of dendritic cells (DCs) with the yeast derivative zymosan or beta-glucan. In addition, two key signaling molecules, Syk and PLCgamma2 are also recruited to lipid rafts upon the activation of Dectin-1, suggesting that lipid raft microdomains facilitate Dectin-1 signaling. Disruption of lipid raft integrity with the synthetic drug, methyl-beta-cyclodextrin (betamD) leads to reduced intracellular Ca2+ flux and defective Syk and ERK phosphorylation in Dectin-1-activated DCs. Furthermore, betamD-treated DCs have significantly attenuated production of IL-2, IL-10, and TNFalpha upon Dectin-1 engagement, and they also exhibit impaired phagocytosis of zymosan particles. Taken together, the data indicate that Dectin-1 and perhaps also other CLRs are recruited to lipid rafts upon activation and that the integrity of lipid rafts is important for the signaling and cellular functions initiated by this class of innate receptors.
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Affiliation(s)
- Shengli Xu
- Laboratory of Immunology, Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore 138668
| | - Jianxin Huo
- Laboratory of Immunology, Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore 138668
| | - Merry Gunawan
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - I-Hsin Su
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Kong-Peng Lam
- Laboratory of Immunology, Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore 138668; Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119074
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Herzog S, Reth M, Jumaa H. Regulation of B-cell proliferation and differentiation by pre-B-cell receptor signalling. Nat Rev Immunol 2009; 9:195-205. [PMID: 19240758 DOI: 10.1038/nri2491] [Citation(s) in RCA: 230] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The pre-B-cell receptor (pre-BCR) is expressed following the productive recombination of the immunoglobulin heavy chain gene. Signals through the pre-BCR are required for initiating diverse processes in pre-B cells, including proliferation and recombination of the light chain gene, which eventually lead to the differentiation of pre-B cells to immature B cells. However, the molecular mechanisms by which the pre-BCR promotes these processes remain largely unresolved. Recent findings suggest that forkhead box O (FOXO) transcription factors connect pre-BCR signalling to the activation of the recombination machinery. In this Review, we discuss how FOXO transcription factors are regulated by the pre-BCR to allow the progression of the cell cycle and the recombination of the light chain gene.
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Affiliation(s)
- Sebastian Herzog
- Centre for Biological Signalling Studies, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
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43
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Pani B, Singh BB. Lipid rafts/caveolae as microdomains of calcium signaling. Cell Calcium 2009; 45:625-33. [PMID: 19324409 DOI: 10.1016/j.ceca.2009.02.009] [Citation(s) in RCA: 203] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2009] [Revised: 02/24/2009] [Accepted: 02/26/2009] [Indexed: 10/21/2022]
Abstract
Ca(2+) is a major signaling molecule in both excitable and non-excitable cells, where it serves critical functions ranging from cell growth to differentiation to cell death. The physiological functions of these cells are tightly regulated in response to changes in cytosolic Ca(2+) that is achieved by the activation of several plasma membrane (PM) Ca(2+) channels as well as release of Ca(2+) from the internal stores. One such channel is referred to as store-operated Ca(2+) channel that is activated by the release of endoplasmic reticulum (ER) Ca(2+) which initiates store-operated Ca(2+) entry (SOCE). Recent advances in the field suggest that some members of TRPCs and Orai channels function as SOCE channels. However, the molecular mechanisms that regulate channel activity and the exact nature of where these channels are assembled and regulated remain elusive. Research from several laboratories has demonstrated that key proteins involved in Ca(2+) signaling are localized in discrete PM lipid rafts/caveolar microdomains. Lipid rafts are cholesterol and sphingolipid-enriched microdomains that function as unique signal transduction platforms. In addition lipid rafts are dynamic in nature which tends to scaffold certain signaling molecules while excluding others. By such spatial segregation, lipid rafts not only provide a favorable environment for intra-molecular cross-talk but also aid to expedite the signal relay. Importantly, Ca(2+) signaling is shown to initiate from these lipid raft microdomains. Clustering of Ca(2+) channels and their regulators in such microdomains can provide an exquisite spatiotemporal regulation of Ca(2+)-mediated cellular function. Thus in this review we discuss PM lipid rafts and caveolae as Ca(2+)-signaling microdomains and highlight their importance in organizing and regulating SOCE channels.
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Affiliation(s)
- Biswaranjan Pani
- Department of Biochemistry and Molecular Biology, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND 58201, USA
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Conley ME, Dobbs AK, Farmer DM, Kilic S, Paris K, Grigoriadou S, Coustan-Smith E, Howard V, Campana D. Primary B cell immunodeficiencies: comparisons and contrasts. Annu Rev Immunol 2009; 27:199-227. [PMID: 19302039 DOI: 10.1146/annurev.immunol.021908.132649] [Citation(s) in RCA: 281] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Sophisticated genetic tools have made possible the identification of the genes responsible for most well-described immunodeficiencies in the past 15 years. Mutations in Btk, components of the pre-B cell and B cell receptor (lambda5, Igalpha, Igbeta), or the scaffold protein BLNK account for approximately 90% of patients with defects in early B cell development. Hyper-IgM syndromes result from mutations in CD40 ligand, CD40, AID, or UNG in 70-80% of affected patients. Rare defects in ICOS or CD19 can result in a clinical picture that is consistent with common variable immunodeficiency, and as many as 10% of patients with this disorder have heterozygous amino acid substitutions in TACI. For all these disorders, there is considerable clinical heterogeneity in patients with the same mutation. Identifying the genetic and environmental factors that influence the clinical phenotype may enhance patient care and our understanding of normal B cell development.
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Affiliation(s)
- Mary Ellen Conley
- Department of Pediatrics, University of Tennessee College of Medicine, Memphis, Tennessee 38163, USA.
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45
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Moreau T, Bardin F, Barlogis V, Le Deist F, Chabannon C, Tonnelle C. Hematopoietic engraftment of XLA bone marrow CD34(+) cells in NOG/SCID mice. Cytotherapy 2009; 11:198-205. [PMID: 19235603 DOI: 10.1080/14653240802716616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
BACKGROUND AIMS X-linked agammaglobulinemia (XLA) is a rare primary immunodeficiency associated with mutations of the BTK (Bruton agammaglobulinemia tyrosine kinase) gene. Non-functional BTK leads to a severe decline in peripheral B cells and profound pan-hypogammaglobulinemia. Substitutive immunoglobulin replacement therapy improves long-term survival but remains a symptomatic rather than curative treatment that does not provide an optimal quality of life. Hematopoietic stem cell gene therapy represents a potentially curative treatment. Thorough pre-clinical testing of innovative therapies requires that adequate disease models are available. Invalidation of the murine btk gene produces a phenotype that is less severe than the human disease; alternatively, xenotransplantation of human hematopoietic progenitors obtained from XLA patients may provide a model for testing new treatment procedures. METHODS The standard of care for XLA patients rarely offers an opportunity to collect peripheral blood or bone marrow (BM) hematopoietic progenitors; however, we had access to two BM samples obtained from such individuals. We analyzed hematopoietic engraftment of immunoselected CD34(+) cells from these samples in NOD/SCID/ gammac(null) (NOG) mice. RESULTS In both cases, human hematopoietic cells were readily detected in BM and thymus, and at low levels in spleen and peripheral blood. Unexpectedly, the early defect in B-lymphoid differentiation associated with XLA was not accurately reproduced in NOG mice, as large amounts of pre-B cells were found in BM. CONCLUSIONS These results support the existence of differences in environmental regulation of B-cell ontogeny between mice and humans. This questions the relevance of the NOG xenograft model for pre-clinical study of XLA gene therapy.
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Affiliation(s)
- Thomas Moreau
- Institut Paoli-Calmettes, Centre de Thérapie Cellulaire et Génique, Marseille, France
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Abstract
Ligand binding to the multichain immune recognition receptors (MIRRs) leads to receptor triggering and subsequent lymphocyte activation. MIRR signal transduction pathways have been extensively studied, but it is still not clear how binding of the ligand to the receptor is initially communicated across the plasma membrane to the cells interior. Models proposed for MIRR triggering can be grouped into three categories. Firstly, ligand binding invokes receptor clustering, resulting in the approximation of kinases to the MIRR and receptor phosphorylation. Secondly, ligand binding induces a conformational change of the receptor. Thirdly, upon ligand-binding, receptors and kinases are segregated from phosphatases, leading to a net phosphorylation of the receptor. In this review, we focus on the homodclustering induced by multivalent ligands, the heterodustering induced by simultaneous binding of the ligand to the MIRR and a coreceptor and the pseudodimer model.
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47
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Oda A, Ono T, Yamamoto M, Goitsuka R, Kitamura D. PKC eta directs induction of IRF-4 expression and Ig kappa gene rearrangement in pre-BCR signaling pathway. Int Immunol 2008; 20:1417-26. [PMID: 18780722 DOI: 10.1093/intimm/dxn101] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Pre-B cell receptor (pre-BCR) signals promote pre-B cell differentiation, in which the adaptor protein B-cell linker (BLNK) plays a crucial role. However, the molecular pathways downstream of BLNK are currently unclear. Utilizing pre-B leukemia cell lines (BKO84 and others) derived from BLNK-deficient mice as in vitro models of the pre-B cell differentiation, we have demonstrated that reconstitution of BLNK as well as an active form of protein kinase C (PKC)eta induces the differentiation events, such as pre-BCR down-regulation and kappa gene rearrangement. Here we show that the same events are induced by cross-linking of pre-BCR with anti-mu antibody in these pre-B cell lines, as well as in ex vivo pre-B cells from BLNK-deficient mice, suggesting a function of BLNK as an internal cross-linker of pre-BCR. Anti-mu treatment of BKO84 cells up-regulated membrane recruitment of PKC eta and the expression of IRF-4, a transcription factor known to promote light chain gene rearrangements. Anti-mu induction of surface kappa chain on BKO84 cells was blocked by reagents that inhibit phospholipase C or PKC. Enforced expression of the active PKC eta in BKO84 cells resulted in up-regulation of IRF-4 expression. Conversely, siRNA-mediated silencing of PKC eta expression strikingly attenuated the anti-mu-induced IRF-4 expression and kappa gene rearrangement, which were restored by PKC eta reconstitution. Finally, enforced expression of IRF-4, but not of BLNK, in the PKC eta-silenced BKO84 cells resulted in kappa gene rearrangement. These results indicate that PKC eta directs the induction of IRF-4 expression downstream of BLNK in the pre-BCR signaling pathway promoting kappa gene rearrangement.
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Affiliation(s)
- Akihisa Oda
- Division of Molecular Biology, Tokyo University of Science, Noda, Chiba 278-0022, Japan
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Chakrabandhu K, Huault S, Garmy N, Fantini J, Stebe E, Mailfert S, Marguet D, Hueber AO. The extracellular glycosphingolipid-binding motif of Fas defines its internalization route, mode and outcome of signals upon activation by ligand. Cell Death Differ 2008; 15:1824-37. [DOI: 10.1038/cdd.2008.115] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Abstract
A unique type of combinatorial protein libraries has been constructed. These libraries are based on the pre-B cell receptor (pre-BCR). The pre-BCR is a protein that is produced during normal development of the antibody repertoire. Unlike that of canonical antibodies, the pre-BCR subunit is a trimer that is composed of an antibody heavy chain paired with two surrogate light chain (SLC) components. Combinatorial libraries based on these pre-BCR proteins in which diverse heavy chains are paired with a fixed SLC were expressed in mammalian, Escherichia coli, and phagemid systems. These libraries contain members that have nanomolar affinity for antigen. We term this type of antigen-binding protein a "surrobody" to distinguish it from the canonical antibody molecule.
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50
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Sohn HW, Tolar P, Pierce SK. Membrane heterogeneities in the formation of B cell receptor-Lyn kinase microclusters and the immune synapse. ACTA ACUST UNITED AC 2008; 182:367-79. [PMID: 18644892 PMCID: PMC2483512 DOI: 10.1083/jcb.200802007] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Antigen binding to the B cell receptors (BCRs) induces BCR clustering, phosphorylation of BCRs by the Src family kinase Lyn, initiation of signaling, and formation of an immune synapse. We investigated B cells as they first encountered antigen on a membrane using live cell high resolution total internal reflection fluorescence microscopy in conjunction with fluorescence resonance energy transfer. Newly formed BCR microclusters perturb the local membrane microenvironment, leading to association with a lipid raft probe. This early event is BCR intrinsic and independent of BCR signaling. Association of BCR microclusters with membrane-tethered Lyn depends on Lyn activity and persists as microclusters accumulate and form an immune synapse. Membrane perturbation and BCR–Lyn association correlate both temporally and spatially with the transition of microclustered BCRs from a “closed” to an “open” active signaling conformation. Visualization and analysis of the earliest events in BCR signaling highlight the importance of the membrane microenvironment for formation of BCR–Lyn complexes and the B cell immune synapse.
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Affiliation(s)
- Hae Won Sohn
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
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