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Germinal center

Zhangguo Chen, Katherine Gowan, Sonia M Leach, Sawanee S Viboolsittiseri, Ameet K Mishra, Tanya Kadoishi, Katrina Diener, Bifeng Gao, Kenneth Jones, Jing H Wang
BACKGROUND: Whole genome next generation sequencing (NGS) is increasingly employed to detect genomic rearrangements in cancer genomes, especially in lymphoid malignancies. We recently established a unique mouse model by specifically deleting a key non-homologous end-joining DNA repair gene, Xrcc4, and a cell cycle checkpoint gene, Trp53, in germinal center B cells. This mouse model spontaneously develops mature B cell lymphomas (termed G1XP lymphomas). RESULTS: Here, we attempt to employ whole genome NGS to identify novel structural rearrangements, in particular inter-chromosomal translocations (CTXs), in these G1XP lymphomas...
October 21, 2016: BMC Genomics
Felix M Wensveen, Erik Slinger, Martijn Ha van Attekum, Robert Brink, Eric Eldering
Upon antigen encounter, the responsive B cell pool undergoes stringent selection which eliminates cells with low B cell receptor (BCR) affinity. Already before formation of the germinal center, activated B cells of low-affinity are negatively selected in a process that is molecularly not well understood. In this study, we investigated the mechanism behind pre-GC affinity-mediated B cell selection. We applied affinity mutants of HEL antigen and found that rapidly after activation B cells become highly dependent on the cytokine BAFF...
October 20, 2016: Scientific Reports
Zijun Y Xu-Monette, Ling Li, John C Byrd, Kausar J Jabbar, Ganiraju C Manyam, Charlotte Maria de Winde, Michiel van den Brand, Alexandar Tzankov, Carlo Visco, Jing Wang, Karen Dybkaer, April Chiu, Attilio Orazi, Youli Zu, Govind Bhagat, Kristy L Richards, Eric D Hsi, William W L Choi, Jooryung Huh, Maurilio Ponzoni, Andrés J M Ferreri, Michael B Møller, Ben M Parsons, Jane N Winter, Michael Wang, Fredrick B Hagemeister, Miguel A Piris, J Han van Krieken, L Jeffrey Medeiros, Yong Li, Annemiek B van Spriel, Ken H Young
CD37 (tetraspanin TSPAN26) is a B-cell surface antigen widely expressed on mature B-cells. CD37 is involved in immune regulation and tumor suppression but its function has not been fully elucidated. In this study, we assessed CD37 expression in de novo diffuse large B-cell lymphoma (DLBCL), and investigated its clinical and biologic significance in 773 patients treated with rituximab-CHOP and 231 patients treated with CHOP chemotherapy. We found CD37 loss (CD37(-)) in ~60% of DLBCL predicted significantly decreased survival rates in R-CHOP-treated patients, independent of the International Prognostic Index (IPI), germinal-center-B-cell-like (GCB)/activated-B-cell-like (ABC) cell-of-origin, nodal/extranodal primary origin, and the prognostic factors associated with CD37(-), including TP53 mutation, NF-κB(high), Myc(high), p-STAT3(high), survivin(high), p63(-), and BCL6 translocation...
October 19, 2016: Blood
Alexandre P Meli, Ghislaine Fontés, Danielle T Avery, Scott A Leddon, Mifong Tam, Michael Elliot, Andre Ballesteros-Tato, Jim Miller, Mary M Stevenson, Deborah J Fowell, Stuart G Tangye, Irah L King
T follicular helper (Tfh) cells are a CD4(+) T cell subset critical for long-lived humoral immunity. We hypothesized that integrins play a decisive role in Tfh cell biology. Here we show that Tfh cells expressed a highly active form of leukocyte function-associated antigen-1 (LFA-1) that was required for their survival within the germinal center niche. In addition, LFA-1 promoted expression of Bcl-6, a transcriptional repressor critical for Tfh cell differentiation, and inhibition of LFA-1 abolished Tfh cell generation and prevented protective humoral immunity to intestinal helminth infection...
October 18, 2016: Immunity
Ioana Visan
No abstract text is available yet for this article.
October 19, 2016: Nature Immunology
Derek D Jones, Brian T Gaudette, Joel R Wilmore, Irene Chernova, Alexandra Bortnick, Brendan M Weiss, David Allman
Little is known about the role of mTOR signaling in plasma cell differentiation and function. Furthermore, for reasons not understood, mTOR inhibition reverses antibody-associated disease in a murine model of systemic lupus erythematosus. Here, we have demonstrated that induced B lineage-specific deletion of the gene encoding RAPTOR, an essential signaling adaptor for rapamycin-sensitive mTOR complex 1 (mTORC1), abrogated the generation of antibody-secreting plasma cells in mice. Acute treatment with rapamycin recapitulated the effects of RAPTOR deficiency, and both strategies led to the ablation of newly formed plasma cells in the spleen and bone marrow while also obliterating preexisting germinal centers...
October 17, 2016: Journal of Clinical Investigation
Michel J Massaad, Jia Zhou, Daisuke Tsuchimoto, Janet Chou, Haifa Jabara, Erin Janssen, Salomé Glauzy, Brennan G Olson, Henner Morbach, Toshiro K Ohsumi, Klaus Schmitz, Markianos Kyriacos, Jennifer Kane, Kumiko Torisu, Yusaku Nakabeppu, Luigi D Notarangelo, Eliane Chouery, Andre Megarbane, Peter B Kang, Eman Al-Idrissi, Hasan Aldhekri, Eric Meffre, Masayuki Mizui, George C Tsokos, John P Manis, Waleed Al-Herz, Susan S Wallace, Raif S Geha
Alterations in the apoptosis of immune cells have been associated with autoimmunity. Here, we have identified a homozygous missense mutation in the gene encoding the base excision repair enzyme Nei endonuclease VIII-like 3 (NEIL3) that abolished enzymatic activity in 3 siblings from a consanguineous family. The NEIL3 mutation was associated with fatal recurrent infections, severe autoimmunity, hypogammaglobulinemia, and impaired B cell function in these individuals. The same homozygous NEIL3 mutation was also identified in an asymptomatic individual who exhibited elevated levels of serum autoantibodies and defective peripheral B cell tolerance, but normal B cell function...
October 17, 2016: Journal of Clinical Investigation
Jennifer L Gardell, David C Parker
The delivery of T-cell help to B cells is antigen-specific, MHC-restricted, and CD40L (CD154) dependent. It has been thought that when a T cell recognizes an antigen-presenting B cell, CD40L expressed on the T-cell surface engages with CD40 on the surface of B cells as long as the cells remain conjugated. To study this, we added fluorescently labeled anti-CD40L antibody during overnight incubation of antigen-presenting B cells with antigen-specific T cells. We discovered that CD40L does not remain on the surface of the T cell, but it is transferred to and endocytosed by B cells receiving T-cell help...
October 18, 2016: European Journal of Immunology
Gareth W Jones, David G Hill, Simon A Jones
Tertiary lymphoid organs (TLOs) are frequently observed in tissues affected by non-resolving inflammation as a result of infection, autoimmunity, cancer, and allograft rejection. These highly ordered structures resemble the cellular composition of lymphoid follicles typically associated with the spleen and lymph node compartments. Although TLOs within tissues show varying degrees of organization, they frequently display evidence of segregated T and B cell zones, follicular dendritic cell networks, a supporting stromal reticulum, and high endothelial venules...
2016: Frontiers in Immunology
Linda M Slot, Robbert Hoogeboom, Laura A Smit, Thera A M Wormhoudt, Bart J Biemond, Monique E C M Oud, Esther J M Schilder-Tol, André B Mulder, Aldo Jongejan, Antoine H C van Kampen, Philip M Kluin, Jeroen E J Guikema, Richard J Bende, Carel J M van Noesel
Follicular lymphoma (FL) is an indolent B-cell non-Hodgkin lymphoma able to transform into germinal center-type diffuse large B-cell lymphoma. We describe four extraordinary cases of FL, which progressed to TdT(+)CD20(-) precursor B-lymphoblastic lymphoma (B-LBL). Fluorescence in situ hybridization analysis showed that all four B-LBLs had acquired a MYC translocation on transformation. Comparative genomic hybridization analysis of one case demonstrated that in addition to 26 numerical aberrations that were shared between the FL and B-LBL, deletion of CDKN2A/B and 17q11, 14q32 amplification, and copy-neutral loss of heterozygosity of 9p were gained in the B-LBL cells...
October 14, 2016: American Journal of Pathology
Carlos Wong-Baeza, Albany Reséndiz-Mora, Luis Donis-Maturano, Isabel Wong-Baeza, Luz Zárate-Neira, Juan Carlos Yam-Puc, Juana Calderón-Amador, Yolanda Medina, Carlos Wong, Isabel Baeza, Leopoldo Flores-Romo
Anti-lipid IgG antibodies are produced in some mycobacterial infections and in certain autoimmune diseases [such as anti-phospholipid syndrome, systemic lupus erythematosus (SLE)]. However, few studies have addressed the B cell responses underlying the production of these immunoglobulins. Anti-lipid IgG antibodies are consistently found in a murine model resembling human lupus induced by chlorpromazine-stabilized non-bilayer phospholipid arrangements (NPA). NPA are transitory lipid associations found in the membranes of most cells; when NPA are stabilized they can become immunogenic and induce specific IgG antibodies, which appear to be involved in the development of the mouse model of lupus...
2016: Frontiers in Immunology
H Vroman, I M Bergen, B W S Li, J A C van Hulst, M Lukkes, D van Uden, R W Hendriks, M Kool
BACKGROUND: Chronic exposure to environmental triggers, such as house dust mite (HDM), drives T helper 2 (Th2) cell-mediated asthma. Recent evidence has shown that B-T cell interaction, and in particular germinal center reactions and follicular T helper (Tfh) cells are required for the development of eosinophilic airway inflammation in HDM-driven models containing a sensitization and challenge phase. Whether B-T cell interactions are essential for pulmonary eosinophilic inflammation following chronic allergen provocation remains unknown...
October 15, 2016: Clinical and Experimental Allergy: Journal of the British Society for Allergy and Clinical Immunology
Rohit Mathur, Lalit Sehgal, Ondrej Havranek, Stefan Köhrer, Tamer Khashab, Neeraj Jain, Jan A Burger, Sattva S Neelapu, R Eric Davis, Felipe Samaniego
Histone methylation and demethylation regulates B-cell development, and their deregulation correlates with tumor chemoresistance in diffuse large B-cell lymphoma, limiting curative rates. Since histone methylation status correlates with disease aggressiveness and relapse, we investigated the therapeutic potential of inhibiting histone 3 Lys27 demethylase KDM6B, in-vitro, using the small molecule inhibitor GSK-J4. KDM6B is overexpressed in the DLBCL germinal center B-cell subtype, and higher KDM6B levels are associated with worse survival in DLBCL patients treated with R-CHOP...
October 14, 2016: Haematologica
Satoru Yamasaki, Kanako Shimizu, Kohei Kometani, Maki Sakurai, Masami Kawamura, Shin-Ichiro Fujii
An induction of long-term cellular and humoral immunity is for the goal of vaccines, but the combination of antigens and adjuvant remain unclear. Here, we show, using a cellular vaccine carrying foreign protein antigen plus iNKT cell glycolipid antigen, designated as artificial adjuvant vector cells (aAVCs), that mature XCR1(-) DCs in situ elicit not only ordinal antigen-specific CD4(+)T cells, but also CD4(+) Tfh and germinal center, resulted in inducing long-term antibody production. As a mechanism for leading the long-term antibody production by aAVC, memory CD4(+) Tfh cells but not iNKTfh cells played an important role in a Bcl6 dependent manner...
October 14, 2016: Scientific Reports
Yun Mai, J Jessica Yu, Boris Bartholdy, Zijun Y Xu-Monette, Esther E Knapp, Fei Yuan, Hongshan Chen, B Belinda Ding, Zhihua Yao, Bhaskar Das, Yiyu Zou, Ken He Young, Samir Parekh, B Hilda Ye
Diffuse large B cell lymphomas (DLBCL) contain two major molecular subtypes, namely, the germinal center B cell-like (GCB) and the activated B cell-like (ABC) DLBCLs. It is well documented that ABC-DLBCL cases have a significantly poorer survival response than GCB-DLBCLs in both the CHOP and the R-CHOP eras. However, the underlying cause of this subtype disparity is poorly understood. Nevertheless, these clinical observations raise the possibility for an ABC-DLBCL-specific resistance mechanism that is directed towards one of the CHOP components and inadequately addressed by rituximab...
October 13, 2016: Blood
Young Uk Kim, Byung-Seok Kim, Hoyong Lim, Rick A Wetsel, Yeonseok Chung
CXCR5⁺ T follicular helper (Tfh) cells are associated with aberrant autoantibody production in patients with antibody-mediated autoimmune diseases including lupus. Follicular regulatory T (Tfr) cells expressing CXCR5 and Bcl6 have been recently identified as a specialized subset of Foxp3⁺ regulatory T (Treg) cells that control germinal center reactions. In this study, we show that retroviral transduction of CXCR5 gene in Foxp3⁺ Treg cells induced a stable expression of functional CXCR5 on their surface...
October 17, 2016: Biomolecules & Therapeutics
Yanwen Jiang, Ana Ortega-Molina, Huimin Geng, Hsia-Yuan Ying, Katerina Hatzi, Sara Parsa, Dylan McNally, Ling Wang, Ashley S Doane, Xabier Agirre Ena, Matt Teater, Cem Meydan, Zhuoning Li, David Poloway, Shenqiu Wang, Daisuke Ennishi, David W Scott, Kristy R Stengel, Janice E Kranz, Edward Holson, Sneh Sharma, James W Young, Chi-Shuen Chu, Robert G Roeder, Rita Shaknovich, Scott W Hiebert, Randy D Gascoyne, Wayne Tam, Olivier Elemento, Hans-Guido Wendel, Ari M Melnick
Somatic mutations in CREBBP occur frequently in B-cell lymphoma. Here, we show that loss of CREBBP facilitates development of germinal center derived lymphomas in mice. In both human and murine lymphomas CREBBP loss of function resulted in focal depletion of enhancer H3K27 acetylation and aberrant transcriptional silencing of genes that regulate B-cell signaling and immune responses including class II MHC. Mechanistically, CREBBP regulated enhancers are counter-regulated by the BCL6 transcriptional repressor in a complex with SMRT and HDAC3, which we find bind extensively to MHC class II loci...
October 12, 2016: Cancer Discovery
Douglas Marcotte, Mia Rushe, Robert M Arduini, Christine Lukacs, Kateri Atkins, Xin Sun, Kevin Little, Michael Cullivan, Murugan Paramasivam, Thomas A Patterson, Thomas Hesson, Timothy D McKee, Tricia L May-Dracka, Zhili Xin, Andrea Bertolotti-Ciarlet, Govinda R Bhisetti, Joseph P Lyssikatos, Laura F Silvian
Germinal-center kinase-like kinase (GLK, Map4k3), a GCK-I family kinase, plays multiple roles in regulating apoptosis, amino acid sensing, and immune signaling. We describe here the crystal structure of an activation loop mutant of GLK kinase domain bound to an inhibitor. The structure reveals a weakly associated, activation-loop swapped dimer with more than 20 amino acids of ordered density at the carboxy-terminus. This C-terminal PEST region binds intermolecularly to the hydrophobic groove of the N-terminal domain of a neighboring molecule...
October 11, 2016: Protein Science: a Publication of the Protein Society
Leigh Jones, Wen Qi Ho, Sze Ying, Lakshmi Ramakrishna, Kandhadayar G Srinivasan, Marina Yurieva, Wan Pei Ng, Sharrada Subramaniam, Nur H Hamadee, Sabrina Joseph, Jayashree Dolpady, Koji Atarashi, Kenya Honda, Francesca Zolezzi, Michael Poidinger, Juan J Lafaille, Maria A Curotto de Lafaille
No abstract text is available yet for this article.
October 10, 2016: Scientific Reports
Ravendra Garg, Michael Theaker, Elisa C Martinez, Sylvia van Drunen Littel-van den Hurk
Respiratory syncytial virus (RSV) causes serious respiratory illness in infants and elderly. RSV infection induces short-lived immunity, which leaves people prone to re-infection. In contrast, the RSV fusion (F) protein formulated with a novel adjuvant (∆F/TriAdj) elicits long term protective immunity. A comparison of RSV-immunized mice to mice vaccinated with a single dose of ∆F/TriAdj showed no difference in IgG1 and IgG2a production; however, local IgA secreting memory B cell development and B cell IgA production were significantly lower in RSV vaccinated mice than in ∆F/TriAdj-immunized mice...
October 6, 2016: Virology
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