B cell-targeted therapy with anti-CD20 monoclonal antibody in a mouse model of Graves' hyperthyroidism

Science.gov (United States)

Ueki, I; Abiru, N; Kobayashi, M; Nakahara, M; Ichikawa, T; Eguchi, K; Nagayama, Y

2011-01-01

Graves' disease is a B cell-mediated and T cell-dependent autoimmune disease of the thyroid which is characterized by overproduction of thyroid hormones and thyroid enlargement by agonistic anti-thyrotrophin receptor (TSHR) autoantibody. In addition to antibody secretion, B cells have recently been recognized to function as antigen-presenting/immune-modulatory cells. The present study was designed to evaluate the efficacy of B cell depletion by anti-mouse (m) CD20 monoclonal antibody (mAb) on Graves' hyperthyroidism in a mouse model involving repeated injection of adenovirus expressing TSHR A-subunit (Ad-TSHR289). We observe that a single injection of 250 µg/mouse anti-mCD20 mAb eliminated B cells efficiently from the periphery and spleen and to a lesser extent from the peritoneum for more than 3 weeks. B cell depletion before immunization suppressed an increase in serum immunoglobulin (Ig)G levels, TSHR-specific splenocyte secretion of interferon (IFN)-γ, anti-TSHR antibody production and development of hyperthyroidism. B cell depletion 2 weeks after the first immunization, a time-point at which T cells were primed but antibody production was not observed, was still effective at inhibiting antibody production and disease development without inhibiting splenocyte secretion of IFN-γ. By contrast, B cell depletion in hyperthyroid mice was therapeutically ineffective. Together, these data demonstrate that B cells are critical not only as antibody-producing cells but also as antigen-presenting/immune-modulatory cells in the early phase of the induction of experimental Graves' hyperthyroidism and, although therapeutically less effective, B cell depletion is highly efficient for preventing disease development. PMID:21235532

Radiolabeling of anti-CD20 with Re0-188: liquid kit

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Dias, Carla Roberta; Osso Junior, Joao Alberto [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: carlarobertab@yahoo.com.br; jaosso@ipen.br

2007-07-01

Radioimmunotherapy uses the targeting features of monoclonal antibody to deliver radiation from an attached radionuclide. The radionuclide {sup 188}Re is currently produced from the father nuclide {sup 188}W through a transportable generator system. Because of its easy availability and suitable nuclear properties (E{sub {beta}}{sub MAX} =2.1 MeV, t{sub 1/2}=16.9 h, E{sub {gamma}}=155 keV), this radionuclide is considered an attractive candidate for application as therapeutic agents and could be conveniently utilized for imaging and dosimetric purposes. The objective of this work is the optimization of radiolabeling of anti-CD20 with {sup 188}Re using a liquid formulation. Anti-CD20 was reduced by incubation with 2-ME and purified over a PD-10 column. The number of resulting free SH was assayed with Ellman's reagent. Optimization of radiolabeling was achieved by varying parameters: antibody mass, reducing agent, reaction time and {sup 188}Re volume in the liquid kit. Radiochemical purity of {sup 188}Re-anti-CD20 was evaluated. An average of 12 SH groups per mol in the reductions was found. The best labeling efficiency (> 93%) was achieved in the following conditions: 1 mg anti-CD20; 82.8 mg sodium tartrate; 1 mg SnCl{sub 2}; 0.25 mg gentisic acid, 1 mL {sup 188}Re and reaction time of 1 hour at room temperature. (author)

Experimental myositis inducible with transfer of dendritic cells presenting a skeletal muscle C protein-derived CD8 epitope peptide.

Science.gov (United States)

Okiyama, Naoko; Hasegawa, Hisanori; Oida, Takatoku; Hirata, Shinya; Yokozeki, Hiroo; Fujimoto, Manabu; Miyasaka, Nobuyuki; Kohsaka, Hitoshi

2015-07-01

It is suggested that polymyositis, an autoimmune inflammatory myopathy, is mediated by autoaggressive CD8 T cells. Skeletal muscle C protein is a self-antigen that induces C protein-induced myositis, a murine model of polymyositis. To establish a new murine model of myositis inducible with a single CD8 T-cell epitope peptide that derives from the C protein, three internet-based prediction systems were employed to identify 24 candidate peptides of the immunogenic fragment of the C protein and bind theoretically to major histocompatibility complex class I molecules of C57BL/6 (B6) mice. RMA-S cell assay revealed that a HILIYSDV peptide, amino acid position 399-406 of the C protein, had the highest affinity to the H2-K(b) molecules. Transfer of mature bone marrow-derived dendritic cells pulsed with HILIYSDV induced myositis in naive B6 mice. This myositis was suppressed by anti-CD8-depleting antibodies but not by anti-CD4-depleting antibodies. Because this myositis model is mediated by CD8 T cells independently of CD4 T cells, it should be a useful tool to investigate pathology of polymyositis and develop therapies targeting CD8 T cells. © The Japanese Society for Immunology. 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Safety and efficacy of ofatumumab, a fully human monoclonal anti-CD20 antibody, in patients with relapsed or refractory B-cell chronic lymphocytic leukemia

DEFF Research Database (Denmark)

Coiffier, Bertrand; Lepretre, Stéphane; Pedersen, Lars Møller

2008-01-01

Safety and efficacy of the fully human anti-CD20 monoclonal antibody, ofatumumab, was analyzed in a multicenter dose-escalating study including 33 patients with relapsed or refractory chronic lymphocytic leukemia. Three cohorts of 3 (A), 3 (B), and 27 (C) patients received 4, once weekly, infusio...

Compartmental and dosimetric studies of anti-CD20 labelled with {sup 188}Re; Estudo compartimental e dosimetrico do Anti-CD20 marcado com {sup 188}Re

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Kuramoto, Graciela Barrio

2016-10-01

The radioimmunotherapy (RIT) uses MAbs conjugated to radionuclides α or β{sup -} emitters, both for therapy. Your treatment is based on the irradiation and tumor destruction, preserving the normal organs as the excess radiation. Radionuclides β{sup -} emitters as {sup 131}I, {sup 90}Y, {sup 188}Re {sup 177}Lu and are useful for the development of therapeutic radiopharmaceuticals and, when coupled with MAb and Anti-CD20 it is important mainly for the treatment of non-Hodgkin's lymphomas (NHL). {sup 188}Re (E{sub β} = 2.12 MeV; E{sub γ} = 155 keV; t1/2 = 16.9 h) is an attractive radionuclide for RIT. However, {sup 188}Re can be obtained from a radionuclide generator of {sup 188}W/{sup 188}Re, commercially available, making it convenient for use in research and for clinical routine. The CR of IPEN has a project aimed at the production of radiopharmaceutical {sup 188}Re-Anti-CD20, where the radionuclide can be obtained from a generator system {sup 188}W/{sup 188}Re. With this proposed a study to assess the efficiency of this labeling technique for treatment in accordance compartmental and dosimetry. The objective of this study was to compare the marking of anti-CD20 MAb with {sup 188}Re with the marking of the antibody with {sup 90}Y, {sup 131}I, {sup 177}Lu and {sup 99m}Tc (for their similar chemical characteristics) and {sup 211}At, {sup 213}Bi, {sup 223}Ra and {sup 225}Ac); through the study of labeling techniques reported in literature, the proposal of a compartmental model to evaluate its pharmacokinetic and dosimetric studies, high interest for therapy. The result of the study shows a favorable kinetics for {sup 188}Re, by their physical and chemical characteristics compared to the other evaluated radionuclides. The compartment proposed study describes the metabolism of {sup 188}Reanti- CD20 through a compartment mammillary model, which by their pharmacokinetic analysis, performed compared to products emitters β{sup -131}I-labeled anti CD20, {sup 177

Interactions between ibrutinib and anti-CD20 antibodies; competing effects on the outcome of combination therapy

Science.gov (United States)

Skarzynski, Martin; Niemann, Carsten U; Lee, Yuh Shan; Martyr, Sabrina; Maric, Irina; Salem, Dalia; Stetler-Stevenson, Maryalice; Marti, Gerald E; Calvo, Katherine R; Yuan, Constance; Valdez, Janet; Soto, Susan; Farooqui, Mohammed Z.H.; Herman, Sarah E.M.; Wiestner, Adrian

2015-01-01

Purpose Clinical trials of ibrutinib combined with anti-CD20 monoclonal antibodies (mAbs) for chronic lymphocytic leukemia (CLL) report encouraging results. Paradoxically, in pre-clinical studies in vitro ibrutinib was reported to decrease CD20 expression and inhibits cellular effector mechanisms. We therefore set out to investigate effects of in vivo ibrutinib treatment that could explain this paradox. Experimental Design Patients received single agent ibrutinib (420mg daily) on an investigator-initiated phase 2 trial. Serial blood samples were collected pre-treatment and during treatment for ex vivo functional assays to examine the effects on CLL cell susceptibility to anti-CD20 mAbs. Results We demonstrate that CD20 expression on ibrutinib was rapidly and persistently down-regulated (median reduction 74%, day 28, Pibrutinib were less susceptible to anti-CD20 mAb-mediated complement-dependent cytotoxicity than pre-treatment cells (median reduction 75%, Pibrutinib, providing a likely mechanism for the preserved C3d opsonization. Additionally, ibrutinib significantly inhibited trogocytosis, a major contributor to antigen loss and tumor escape during mAb therapy. Conclusions Our data indicate that ibrutinib promotes both positive and negative interactions with anti-CD20 mAbs, suggesting that successfully harnessing maximal anti-tumor effects of such combinations requires further investigation. PMID:26283682

Compartmental and dosimetric studies of anti-CD20 labelled with 188Re

International Nuclear Information System (INIS)

Kuramoto, Graciela Barrio

2016-01-01

The radioimmunotherapy (RIT) uses MAbs conjugated to radionuclides α or β - emitters, both for therapy. Your treatment is based on the irradiation and tumor destruction, preserving the normal organs as the excess radiation. Radionuclides β - emitters as 131 I, 90 Y, 188 Re 177 Lu and are useful for the development of therapeutic radiopharmaceuticals and, when coupled with MAb and Anti-CD20 it is important mainly for the treatment of non-Hodgkin's lymphomas (NHL). 188 Re (E β = 2.12 MeV; E γ = 155 keV; t1/2 = 16.9 h) is an attractive radionuclide for RIT. However, 188 Re can be obtained from a radionuclide generator of 188 W/ 188 Re, commercially available, making it convenient for use in research and for clinical routine. The CR of IPEN has a project aimed at the production of radiopharmaceutical 188 Re-Anti-CD20, where the radionuclide can be obtained from a generator system 188 W/ 188 Re. With this proposed a study to assess the efficiency of this labeling technique for treatment in accordance compartmental and dosimetry. The objective of this study was to compare the marking of anti-CD20 MAb with 188 Re with the marking of the antibody with 90 Y, 131 I, 177 Lu and 99m Tc (for their similar chemical characteristics) and 211 At, 213 Bi, 223 Ra and 225 Ac); through the study of labeling techniques reported in literature, the proposal of a compartmental model to evaluate its pharmacokinetic and dosimetric studies, high interest for therapy. The result of the study shows a favorable kinetics for 188 Re, by their physical and chemical characteristics compared to the other evaluated radionuclides. The compartment proposed study describes the metabolism of 188 Reanti- CD20 through a compartment mammillary model, which by their pharmacokinetic analysis, performed compared to products emitters β -131 I-labeled anti CD20, 177 Luanti- CD20, the γ emitter 99m Tc-Anti-CD20 and α emitter 211 At-Anti-CD20 presented a elimination constant of approximately 0.05 hours

Double positive CD4+CD8+ T cells: key suppressive role in the production of autoantibodies in systemic lupus erythematosus

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Yongkang Wu

2014-01-01

Full Text Available Background & objectives: The presence of CD4+CD8+ (double positive T cells (DPT in the target organs of several autoimmune diseases has been reported. The aim of this study was to investigate the pathogenic role of DPT in systemic lupus erythematosus (SLE. Methods: A total of 175 SLE cases and 125 matched healthy controls were investigated for CD3+, CD4+, CD8+ lymphocytes and DPT by flow cytometry. Serum samples from SLE patients and controls were tested for antinuclear antibody (ANA, anti-double strain deoxyribonucleic acid (anti-dsDNA, anti-U1 ribonucleoprotein (anti-U1 RNP, anti-sjogren syndrome A (anti-SSA, anti-ribosomal P protein (anti-rib-P, anti-Smith (anti-Sm, anti-Sjogren syndrome B (anti-SSB, complement 3 (C3 and complement 4 (C4. Results: The DPT median and 5-95 per cent range of SLE cases and healthy controls were 0.50 [0.10-2.60] and 0.80 [0.20-2.74] respectively (P<0.001. SLE patients were divided into a ≥1:1000 subgroup and a <1:1000 subgroup according to the ANA titre. The DPT of the former subgroup was significantly lower than that of the latter (P=0.032. The DPT medians of positive subgroups with anti-dsDNA (P<0.001, anti-U1RNP (P=0.018, anti-SSA (P=0.021 or anti-rib-P (P=0.039 were also significantly lower than the negative subgroups. Likewise, DPT was significantly lower in SLE subgroups with low concentration of C3 or C4 than those with high concentration (P<0.006. Interpretation & conclusions: Our findings show that the DPT cells may play a key suppressive role in the production of autoantibodies in SLE. Direct evidence that DPT regulates the pathogenesis of SLE needs to be investigated in future work.

Anti-CD20 Cell Therapies in Multiple Sclerosis—A Fixed Dosing Schedule for Ocrelizumab is Overkill

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Jagannadha Avasarala

2017-10-01

Full Text Available Anti-CD 20 therapies have found significant uses in multiple sclerosis (MS. Based singularly on the accumulated evidence with the use of rituximab (RTX; Rituxan, Genentech, and Biogen in neuroimmunological diseases, ocrelizumab (OCR; Ocrevus, Genentech was developed as a treatment option for MS and selectively targets CD20 B cells, a cell surface antigen found on pre-B cells, mature, and memory B cells, but not on lymphoid stem cells and plasma cells. On the basis of indirect evidence, elimination of the antigen-presenting capabilities and antigen nonspecific immune functions of B cells appear to be central to the therapeutic efficacy of anti-CD20 B-cell therapies. An important question is this—Why does the drug need to be dosed at fixed intervals and not based on a measurable endpoint, such as tracking peripheral CD20 cell counts? There is minimal scientific validity in infusing the drug every 6 months particularly if CD20 cell counts are negligible in the peripheral blood. In this analysis, a case is made for following CD19 cell populations as a surrogate for CD20 cells on a monthly basis to guide OCR redosing parameters and does not follow a scheduled dosing parameter.

Cloning and molecular characterization of the cDNAs encoding the variable regions of an anti-CD20 monoclonal antibody.

Science.gov (United States)

Shanehbandi, Dariush; Majidi, Jafar; Kazemi, Tohid; Baradaran, Behzad; Aghebati-Maleki, Leili

2017-01-01

CD20-based targeting of B-cells in hematologic malignancies and autoimmune disorders is associated with outstanding clinical outcomes. Isolation and characterization of VH and VL cDNAs encoding the variable regions of the heavy and light chains of monoclonal antibodies (MAb) is necessary to produce next generation MAbs and their derivatives such as bispecific antibodies (bsAb) and single-chain variable fragments (scFv). This study was aimed at cloning and characterization of the VH and VL cDNAs from a hybridoma cell line producing an anti-CD20 MAb. VH and VL fragments were amplified, cloned and characterized. Furthermore, amino acid sequences of VH, VL and corresponding complementarity-determining regions (CDR) were determined and compared with those of four approved MAbs including Rituximab (RTX), Ibritumomab tiuxetan, Ofatumumab and GA101. The cloned VH and VL cDNAs were found to be functional and follow a consensus pattern. Amino acid sequences corresponding to the VH and VL fragments also indicated noticeable homologies to those of RTX and Ibritumomab. Furthermore, amino acid sequences of the relating CDRs had remarkable similarities to their counterparts in RTX and Ibritumomab. Successful recovery of VH and VL fragments encourages the development of novel CD20 targeting bsAbs, scFvs, antibody conjugates and T-cells armed with chimeric antigen receptors.

Effects of anti-CD40 mAb on inducing malignant B cells proliferation arrest and apoptosis and its mechanism

International Nuclear Information System (INIS)

Tang Lin; Zhuang Yumei; Zhou Zhaohua; Yu Gehua; Pan Jianzhong; Zhang Xueguang

2002-01-01

Objective: To study the expression of CD 40 molecule and the biological effects mediated by CD 40 molecules on malignant B cells. Methods: Agonistic anti-human CD 40 monoclonal antibody (clone 5C11) was added to cell culture system. Cell counting, PI staining, Annexin-V staining and flow cytometric analysis were used to study the behavior of malignant B cell lines after treatment with mAb clone 5C11. Results: 5C11 induced homotypic aggregation and proliferation arrest and mediated apoptosis in multiple myeloma cell line XG2 that expressed CD 40 strongly; 5C11 induced B lymphoma cell line Daudi homotypic aggregation and proliferation arrest and apoptosis, the apoptosis of XG2 and Daudi by CD40 activation was not mediated by TNF. Conclusion: Agonistic anti-CD 40 mAb 5C11 can inhibit the proliferation of malignant B cells by inducing them to die apoplectically

A Preclinical Population Pharmacokinetic Model for Anti-CD20/CD3 T-Cell-Dependent Bispecific Antibodies.

Science.gov (United States)

Ferl, Gregory Z; Reyes, Arthur; Sun, Liping L; Cheu, Melissa; Oldendorp, Amy; Ramanujan, Saroja; Stefanich, Eric G

2018-05-01

CD20 is a cell-surface receptor expressed by healthy and neoplastic B cells and is a well-established target for biologics used to treat B-cell malignancies. Pharmacokinetic (PK) and pharmacodynamic (PD) data for the anti-CD20/CD3 T-cell-dependent bispecific antibody BTCT4465A were collected in transgenic mouse and nonhuman primate (NHP) studies. Pronounced nonlinearity in drug elimination was observed in the murine studies, and time-varying, nonlinear PK was observed in NHPs, where three empirical drug elimination terms were identified using a mixed-effects modeling approach: i) a constant nonsaturable linear clearance term (7 mL/day/kg); ii) a rapidly decaying time-varying, linear clearance term (t ½  = 1.6 h); and iii) a slowly decaying time-varying, nonlinear clearance term (t ½  = 4.8 days). The two time-varying drug elimination terms approximately track with time scales of B-cell depletion and T-cell migration/expansion within the central blood compartment. The mixed-effects NHP model was scaled to human and prospective clinical simulations were generated. © 2018 The Authors. Clinical and Translational Science published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

Isolation and structure of a cDNA encoding the B1 (CD20) cell-surface antigen of human B lymphocytes

International Nuclear Information System (INIS)

Tender, T.F.; Streuli, M.; Schlossman, S.F.; Saito, H.

1988-01-01

The B1 (CD20) molecule is a M/sub r/ 33,000 phosphoprotein on the surface of human B lymphocytes that may serve a central role in the homoral immune response by regulating B-cell proliferation and differentiation. In this report, a cDNA clone that encodes the B1 molecule was isolated and the amino acid sequence of B1 was determined. B-cell-specific cDNA clones were selected from a human tonsillar cDNA library by differential hybridization with labeled cDNA derived from either size-fractionated B-cell mRNA or size-fractionated T-cell mRNA. Of the 261 cDNA clones isolated, 3 cross-hybridizing cDNA clones were chosen as potential candidates for encoding B1 based on their selective hybridization to RNA from B1-positive cell lines. The longest clone, pB1-21, contained a 2.8-kilobase insert with an 891-base-pair open reading frame that encodes a protein of 33 kDa. mRNA synthesized from the pB1-21 cDNA clone in vitro was translated into a protein of the same apparent molecular weight as B1. Limited proteinase digestion of the pB1-21 translation product and B1 generated peptides of the same sizes, indicating that the pB1-21 cDNA encodes the B1 molecule. Gel blot analysis indicated that pB1-21 hybridized with two mRNA species of 2.8 and 3.4 kilobases only in B1-positive cell lines. The amino acid sequence deduced from the pB1-21 nucleotide sequence apparently lacks a signal sequence and contains three extensive hydrophobic regions. The deduced B1 amino acid sequence shows no significant homology with other known patients

[{sup 177}Lu]DOTA-anti-CD20: Labeling and pre-clinical studies

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Audicio, Paola F., E-mail: paudicio@cin.edu.u [Departamento de Radiofarmacia, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la Republica, Mataojo 2055, 11400 Montevideo (Uruguay); Castellano, Gustavo, E-mail: gcas@famaf.unc.edu.a [FaMAF, Universidad Nacional de Cordoba, Ciudad Universitaria, 5016 Cordoba (Argentina); Tassano, Marcos R.; Rezzano, Maria E.; Fernandez, Marcelo [Departamento de Radiofarmacia, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la Republica, Mataojo 2055, 11400 Montevideo (Uruguay); Riva, Eloisa [Clinica Hematologica ' Prof. Dra. L. Diaz' , Hospital de Clinicas. Av. Italia. sn, Montevideo (Uruguay); Robles, Ana; Cabral, Pablo; Balter, Henia; Oliver, Patricia [Departamento de Radiofarmacia, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la Republica, Mataojo 2055, 11400 Montevideo (Uruguay)

2011-07-15

Anti-CD20 (Rituximab), a specific chimeric monoclonal antibody used in CD20-positive Non-Hodgkin's Lymphoma, was conjugated to a bifunctional quelate (DOTA) and radiolabeled with {sup 177}Lu through a simple method. [{sup 177}Lu]-DOTA-anti-CD20 was obtained with a radiochemical purity higher than 97%, and showed good chemical and biological stability, maintaining its biospecificity to CD20 antigens. Monte Carlo simulation showed high doses deposited on a spheroid tumor mass model. This method seems to be an appropriate alternative for the production of [{sup 177}Lu]-DOTA-anti-CD20 as therapeutic radiopharmaceutical.

Intraläsionale Therapie niedrig maligner primär kutaner B-Zell-Lymphome mit Anti-CD20-Antikörper: Nebenwirkungen korrelieren mit gutem klinischen Ansprechen.

Science.gov (United States)

Eberle, Franziska C; Holstein, Julia; Scheu, Alexander; Fend, Falko; Yazdi, Amir S

2017-03-01

Die intraläsionale Gabe von Anti-CD20-Antikörpern (Rituximab) wurde als effektive Therapieoption für Patienten mit niedrig malignen primär kutanen B-Zell-Lymphomen beschrieben. Bis heute wurden allerdings keine Parameter identifiziert, welche reproduzierbar ein gutes klinisches Ansprechen dieser Therapie vorhersagen. Ziel dieser Studie ist, sowohl das klinische Ansprechen und die unerwünschten Nebenwirkungen als auch die Patientenwahrnehmung hinsichtlich intraläsionaler Injektionen von anti-CD20-Antikörpern zur Behandlung indolenter primär kutaner B-Zell-Lymphome im Vergleich mit anderen Therapien zu evaluieren. Elf Patienten mit einem primär kutanen B-Zell-Lymphom, namentlich primär kutanes Keimzentrumslymphom (n = 9) und primär kutanes Marginalzonenlymphom (n = 2), welche mittels intraläsionalem Anti-CD20-Antikörper behandelt wurden, wurden retrospektiv evaluiert hinsichtlich der Ansprechrate und unerwünschter Nebenwirkungen sowie in Bezug auf deren Selbsteinschätzung dieser und anderer Therapien des primär kutanen B-Zell-Lymphoms. Patienten, deren primär kutanes B-Zell-Lymphom mittels intraläsionaler Gabe von Anti-CD20-Antikörper behandelt wurde, zeigten ein komplettes oder partielles Ansprechen in 45 % beziehungsweise 27 % aller Patienten. Speziell Patienten mit grippeähnlichen Symptomen nach erfolgter Injektion zeigten ein gutes Ansprechen. Die Mehrheit der Patienten empfand die Therapie mit Rituximab als die beste Therapie im Vergleich zu anderen Therapien wie beispielsweise chirurgische Exzision oder Radiotherapie. Intraläsionales Rituximab ist eine effektive Therapie mit hoher Patientenzufriedenheit. Starke therapiebedingte Nebenwirkungen wie Fieber, Schüttelfrost und Kopfschmerzen nach Gabe von Rituximab könnten als Indikator für gute Wirksamkeit dienen. © 2017 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Induction of CD4 suppressor T cells with anti-Leu-8 antibody

International Nuclear Information System (INIS)

Kanof, M.E.; Strober, W.; James, S.P.

1987-01-01

To characterize the conditions under which CD4 T cells suppress polyclonal immunoglobulin synthesis, we investigated the capacity of CD4 T cells that coexpress the surface antigen recognized by the monoclonal antibody anti-Leu-8 to mediate suppression. In an in vitro system devoid of CD8 T cells, CD4, Leu-8+ T cells suppressed pokeweed mitogen-induced immunoglobulin synthesis. Similarly, suppressor function was induced in unfractionated CD4 T cell populations after incubation with anti-Leu-8 antibody under cross-linking conditions. This induction of suppressor function by anti-Leu-8 antibody was not due to expansion of the CD4, Leu-8+ T cell population because CD4 T cells did not proliferate in response to anti-Leu-8 antibody. However, CD4, Leu-8+ T cell-mediated suppression was radiosensitive. Finally, CD4, Leu-8+ T cells do not inhibit immunoglobulin synthesis when T cell lymphokines were used in place of helper CD4 T cells (CD4, Leu-8- T cells), suggesting that CD4 T cell-mediated suppression occurs at the T cell level. We conclude that CD4 T cells can be induced to suppress immunoglobulin synthesis by modulation of the membrane antigen recognized by anti-Leu-8 antibody

TCRγδ+CD4−CD8− T Cells Suppress the CD8+ T-Cell Response to Hepatitis B Virus Peptides, and Are Associated with Viral Control in Chronic Hepatitis B

Science.gov (United States)

Lai, Qintao; Ma, Shiwu; Ge, Jun; Huang, Zuxiong; Huang, Xuan; Jiang, Xiaotao; Li, Yongyin; Zhang, Mingxia; Zhang, Xiaoyong; Sun, Jian; Abbott, William G. H.; Hou, Jinlin

2014-01-01

The immune mechanisms underlying failure to achieve hepatitis B e antigen (HBeAg) seroconversion associated with viral control in chronic hepatitis B (CHB) remain unclear. Here we investigated the role of CD4−CD8− T (double-negative T; DNT) cells including TCRαβ+ DNT (αβ DNT) and TCRγδ+ DNT (γδ DNT) cells. Frequencies of circulating DNT cell subsets were measured by flow cytometry in a retrospective cohort of 51 telbivudine-treated HBeAg-positive CHB patients, 25 immune tolerant carriers (IT), 33 inactive carriers (IC), and 37 healthy controls (HC). We found that γδ DNT cell frequencies did not significantly change during treatment, being lower at baseline (P = 0.019) in patients with HBeAg seroconversion after 52 weeks of antiviral therapy (n = 20) than in those without (n = 31), and higher in the total CHB and IT than IC and HC groups (P<0.001). αβ DNT cell frequencies were similar for all groups. In vitro, γδ DNT cells suppressed HBV core peptide-stimulated interferon-γ and tumor necrosis factor-α production in TCRαβ+CD8+ T cells, which may require cell–cell contact, and could be partially reversed by anti-NKG2A. These findings suggest that γδ DNT cells limit CD8+ T cell response to HBV, and may impede HBeAg seroconversion in CHB. PMID:24551107

Type I CD20 Antibodies Recruit the B Cell Receptor for Complement-Dependent Lysis of Malignant B Cells

NARCIS (Netherlands)

Engelberts, Patrick J.; Voorhorst, Marleen; Schuurman, Janine; van Meerten, Tom; Bakker, Joost M.; Vink, Tom; Mackus, Wendy J. M.; Breij, Esther C. W.; Derer, Stefanie; Valerius, Thomas; van de Winkel, Jan G. J.; Parren, Paul W. H. I.; Beurskens, Frank J.

2016-01-01

Human IgG1 type I CD20 Abs, such as rituximab and ofatumumab (OFA), efficiently induce complement-dependent cytotoxicity (CDC) of CD20(+) B cells by binding of C1 to hexamerized Fc domains. Unexpectedly, we found that type I CD20 Ab F(ab ')2 fragments, as well as C1q-binding-deficient IgG mutants,

Comparison of anti-CD3 and anti-CD28-coated beads with soluble anti-CD3 for expanding human T cells: Differing impact on CD8 T cell phenotype and responsiveness to restimulation

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Kurlander Roger J

2010-10-01

Full Text Available Abstract Background The ability to expand virus- or tumor-specific T cells without damaging their functional capabilities is critical for success adoptive transfer immunotherapy of patients with opportunistic infection or tumor. Careful comparisons can help identify expansion methods better suited for particular clinical settings and identify recurrent deficiencies requiring new innovation. Methods We compared the efficacy of magnetic beads coated with anti-CD3 and anti-CD28 (anti-CD3/CD28 beads, and soluble anti-CD3 plus mixed mononuclear cells (designated a rapid expansion protocol or REP in expanding normal human T cells. Results Both anti-CD3/CD28 beads and soluble anti-CD3 promoted extensive expansion. Beads stimulated greater CD4 cell growth (geometric mean of 56- versus 27-fold (p Conclusions Anti-CD3/CD28 beads are highly effective for expanding CD4 cells, but soluble anti-CD3 has significant potential advantages for expanding CD8 T cells, particularly where preservation of phenotypically "young" CD8 cells would be desirable, or where the T cells of interest have been antigen-stimulated in vitro or in vivo in the recent past.

HTLV-1 specific CD8+ T cell function augmented by blockade of 2B4/CD48 interaction in HTLV-1 infection.

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Chibueze Chioma Ezinne

Full Text Available CD8+ T cell response is important in the response to viral infections; this response though is regulated by inhibitory receptors. Expression of inhibitory receptors has been positively correlated with CD8+ T cell exhaustion; the consequent effect of simultaneous blockade of these inhibitory receptors on CD8+ T cell response in viral infections have been studied, however, the role of individual blockade of receptor-ligand pair is unclear. 2B4/CD48 interaction is involved in CD8+T cell regulation, its signal transducer SAP (signaling lymphocyte activation molecule (SLAM-associated protein is required for stimulatory function of 2B4/CD244 on lymphocytes hence, we analyzed 2B4/CD244 (natural killer cell receptor and SAP (signaling lymphocyte activation molecule(SLAM-associated protein on total CD8+ and HTLV-1 specific CD8+T cells in HTLV-1 infection and the effect of blockade of interaction with ligand CD48 on HTLV-1 specific CD8+ T cell function. We observed a high expression of 2B4/CD244 on CD8+ T cells relative to uninfected and further upregulation on HTLV-1 specific CD8+ T cells. 2B4+ CD8+ T cells exhibited more of an effector and terminally differentiated memory phenotype. Blockade of 2B4/CD48 interaction resulted in improvement in function via perforin expression and degranulation as measured by CD107a surface mobilization on HTLV-1 specific CD8+ T cells. In the light of these findings, we thus propose an inhibitory role for 2B4/CD48 interaction on CD8+T cell function.

A role for CD4+ but not CD8+ T cells in immunity to Schistosoma mansoni induced by 20 krad-irradiated and Ro 11-3128-terminated infections

International Nuclear Information System (INIS)

Vignali, D.A.A.; Bickle, Q.D.; Taylor, M.G.; Crocker, P.; Cobbold, S.; Waldmann, H

1989-01-01

The role of CD4 + (L3/T4 + ) and CD8 + (Lyt-2 + ) T cells in immunity to Schistosoma mansoni induced by 20 krad-irradiated and Ro 11-terminated infections in mice was investigated directly by in vivo depletion of these subsets with cytotoxic rat monoclonal antibodies (mAb). Effective physical depletion was demonstrated by flow cytometric analysis and immunohistochemical staining. Functional depletion of helper activity following anti-CD4 treatment was indicated by an abrogation of concanavalin A(Con A)-induced colony-stimulating factor (CSF) release, while anti-CD8 treatment had no effect in these assays. Pre-existing S. mansoni-specific antibody levels were unaffected by anti-CD4 and anti-CD8 treatment. In vivo depletion of CD4 + T cells resulted in a dramatic reduction in immunity induced by one (up to 100%) and two (up to 70%) vaccinations with 20 krad-irradiated cercariae and also of resistance induced by Ro 11-attenuated infections (up to 100%). Depletion of CD8 + T cells had no effect on resistance induced by any of the vaccination protocols investigated. A correlation was observed between resistance and T cell-induced, macrophage-mediated killing of schistosomula in vitro, both of which were abrogated following anti-CD4 treatment but were unaffected by CD8 + T-cell depletion. The possible role of CD4 + T cells in vivo and the implications for vaccine development are discussed. (author)

The diabetogenic VPS13C/C2CD4A/C2CD4B rs7172432 variant impairs glucose-stimulated insulin response in 5,722 non-diabetic Danish individuals

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Grarup, N; Overvad, M; Sparsø, T

2011-01-01

A genome-wide association study in the Japanese population reported two genome-wide significant loci associated with type 2 diabetes of which the VPS13C/C2CD4A/C2CD4B locus was replicated in Europeans. We looked for potential associations between the diabetogenic VPS13C/C2CD4A/C2CD4B rs7172432 va...

Subcutaneous injections of low-dose veltuzumab (humanized anti-CD20 antibody) are safe and active in patients with indolent non-Hodgkin's lymphoma.

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Negrea, George O; Elstrom, Rebecca; Allen, Steven L; Rai, Kanti R; Abbasi, Rashid M; Farber, Charles M; Teoh, Nick; Horne, Heather; Wegener, William A; Goldenberg, David M

2011-04-01

Subcutaneous injections of anti-CD20 antibodies may offer benefits to both patients and the healthcare system for treatment of B-cell malignancies. A pilot study was undertaken to evaluate the potential for subcutaneous dosing with 2(nd) generation anti-CD20 antibody veltuzumab in patients with CD20(+) indolent non-Hodgkin's lymphoma. Patients with previously untreated or relapsed disease received 4 doses of 80, 160, or 320 mg veltuzumab injected subcutaneously every two weeks. Responses were assessed by computed tomography scans, with other evaluations including adverse events, safety laboratories, B-cell blood levels, serum veltuzumab levels, and human anti-veltuzumab antibody (HAHA) titers. Seventeen patients (14 follicular lymphoma; 13 stage III or IV disease; 5 treatment-naive) completed treatment with only occasional, mild-moderate, transient injection reactions and no other safety issues. Subcutaneous veltuzumab demonstrated a slow release pattern over several days, achieving a mean Cmax of 19, 25 and 63 μg/mL at 80, 160, and 320 mg doses for a total of 4 administrations, respectively. Depletion of circulating B cells occurred after the first injection. The objective response rate (partial responses plus complete responses plus complete responses unconfirmed) was 47% (8/17) with a complete response/complete response unconfirmed rate of 24% (4/17); 4 of 8 objective responses continued for 60 weeks or more. All serum samples evaluated for human anti-veltuzumab antibody were negative. Subcutaneous injections of low-dose veltuzumab are convenient, well tolerated, and capable of achieving sustained serum levels, B-cell depletion, and durable objective responses in indolent non-Hodgkin's lymphoma. (Clinicaltrials.gov identifier: NCT00546793).

CD20-based Immunotherapy of B-cell Derived Hematologic Malignancies.

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Shanehbandi, Dariush; Majidi, Jafar; Kazemi, Tohid; Baradaran, Behzad; Aghebati-Maleki, Leili

2017-01-01

CD20 is a surface antigen, which is expressed at certain stages of B-cell differentiation. Targeting the CD20-positive B-cells with therapeutic monoclonal antibodies (MAbs) has been an effectual strategy in the treatment of hematologic malignancies such as non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukemia (CLL). Initial success with Rituximab (RTX) has encouraged the creation and development of more effective CD20 based therapeutics. However, treatment with conventional MAbs has not been adequate to overcome the problems such as refractory/ relapsed disease. In this regard, new generations of MAbs with enhanced affinity or improved anti-tumor properties have been developed. CD20 directed therapeutics have heterogeneous features and mechanisms of action. Hence, having sufficient knowledge on the immunological and molecular aspects of CD20 based cancer therapy is necessary for predicting the clinical outcomes and taking the necessary measures. An extensive search was performed in PubMed and similar databases for peer-reviewed articles concerning the biology, function and characteristics of CD20 molecule as well as the mechanisms of action and evolutionary process of CD20 targeting agents. This review provides information about the current situation of CD20 targeting immunotherapeutics including MAbs, bispecific antibodies (which exert multiple functions or involve Tcells in tumor elimination) and CAR T-cells (engineered T-cells armed with chimeric antigen receptors). Moreover, limitations, challenges and available solutions regarding the application of CD20 targeting treatments are addressed. Utilization of CD20-targeted therapeutics, due to their diverse properties, requires special considerations. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

miR-150 Regulates Memory CD8 T Cell Differentiation via c-Myb

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Zeyu Chen

2017-09-01

Full Text Available MicroRNAs play an important role in T cell responses. However, how microRNAs regulate CD8 T cell memory remains poorly defined. Here, we found that miR-150 negatively regulates CD8 T cell memory in vivo. Genetic deletion of miR-150 disrupted the balance between memory precursor and terminal effector CD8 T cells following acute viral infection. Moreover, miR-150-deficient memory CD8 T cells were more protective upon rechallenge. A key circuit whereby miR-150 repressed memory CD8 T cell development through the transcription factor c-Myb was identified. Without miR-150, c-Myb was upregulated and anti-apoptotic targets of c-Myb, such as Bcl-2 and Bcl-xL, were also increased, suggesting a miR-150-c-Myb survival circuit during memory CD8 T cell development. Indeed, overexpression of non-repressible c-Myb rescued the memory CD8 T cell defects caused by overexpression of miR-150. Overall, these results identify a key role for miR-150 in memory CD8 T cells through a c-Myb-controlled enhanced survival circuit.

Antibody response is required for protection from Theiler's virus-induced encephalitis in C57BL/6 mice in the absence of CD8+ T cells

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Kang, B.-S.; Palma, Joann P.; Lyman, Michael A.; Dal Canto, Mauro; Kim, Byung S.

2005-01-01

Intracerebral infection of susceptible mice with Theiler's murine encephalomyelitis virus (TMEV) induces immune-mediated demyelinating disease and this system serves as a relevant infectious model for human multiple sclerosis. It was previously shown that β 2 M-deficient C57BL/6 mice lacking functional CD8 + T cells display increased viral persistence and enhanced susceptibility to TMEV-induced demyelination, and yet the majority of mice are free of clinical signs. To understand the mechanisms involved in this general resistance of C57BL/6 mice in the absence of CTL responses, mice (μMT) deficient in the B-cell compartment lacking membrane IgM molecules were treated with anti-CD8 antibody and then infected with TMEV. Although little difference in the proliferative responses of peripheral T cells to UV-inactivated TMEV and the resistance to demyelinating disease was observed between virus-infected μMT and control B6 mice, the levels of CD4 + T cells were higher in the CNS of μMT mice. However, after treatment with anti-CD8 antibody, 100% of the mice displayed clinical gray matter disease and prolonged viral persistence in μMT mice, while only 10% of B6 mice showed clinical symptoms and very low viral persistence. Transfusion of sera from TMEV-infected B6 mice into anti-CD8 antibody-treated μMT mice partially restored resistance to virus-induced encephalitis. These results indicate that the early anti-viral antibody response is also important in the protection from TMEV-induced encephalitis particularly in the absence of CD8 + T cells

Subcutaneous injections of low-dose veltuzumab (humanized anti-CD20 antibody) are safe and active in patients with indolent non-Hodgkin’s lymphoma

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Negrea, George O.; Elstrom, Rebecca; Allen, Steven L.; Rai, Kanti R.; Abbasi, Rashid M.; Farber, Charles M.; Teoh, Nick; Horne, Heather; Wegener, William A.; Goldenberg, David M.

2011-01-01

Background Subcutaneous injections of anti-CD20 antibodies may offer benefits to both patients and the healthcare system for treatment of B-cell malignancies. Design and Methods A pilot study was undertaken to evaluate the potential for subcutaneous dosing with 2nd generation anti-CD20 antibody veltuzumab in patients with CD20+ indolent non-Hodgkin’s lymphoma. Patients with previously untreated or relapsed disease received 4 doses of 80, 160, or 320 mg veltuzumab injected subcutaneously every two weeks. Responses were assessed by computed tomography scans, with other evaluations including adverse events, safety laboratories, B-cell blood levels, serum veltuzumab levels, and human anti-veltuzumab antibody (HAHA) titers. Results Seventeen patients (14 follicular lymphoma; 13 stage III or IV disease; 5 treatment-naive) completed treatment with only occasional, mild-moderate, transient injection reactions and no other safety issues. Subcutaneous veltuzumab demonstrated a slow release pattern over several days, achieving a mean Cmax of 19, 25 and 63 μg/mL at 80, 160, and 320 mg doses for a total of 4 administrations, respectively. Depletion of circulating B cells occurred after the first injection. The objective response rate (partial responses plus complete responses plus complete responses unconfirmed) was 47% (8/17) with a complete response/complete response unconfirmed rate of 24% (4/17); 4 of 8 objective responses continued for 60 weeks or more. All serum samples evaluated for human anti-veltuzumab antibody were negative. Conclusions Subcutaneous injections of low-dose veltuzumab are convenient, well tolerated, and capable of achieving sustained serum levels, B-cell depletion, and durable objective responses in indolent non-Hodgkin’s lymphoma. (Clinicaltrials.gov identifier: NCT00546793) PMID:21173095

Ibrutinib interferes with the cell-mediated anti-tumor activities of therapeutic CD20 antibodies: implications for combination therapy

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Da Roit, F.; Engelberts, P. J.; Taylor, R. P.

2015-01-01

The novel Bruton tyrosine kinase inhibitor ibrutinib and phosphatidyl-4-5-biphosphate 3-kinase-delta inhibitor idelalisib are promising drugs for the treatment of chronic lymphocytic leukemia and B-cell non-Hodgkin lymphoma, either alone or in combination with anti-CD20 antibodies. We investigated...... the possible positive or negative impact of these drugs on all known mechanisms of action of both type I and type II anti-CD20 antibodies. Pretreatment with ibrutinib for 1 hour did not increase direct cell death of cell lines or chronic lymphocytic leukemia samples mediated by anti-CD20 antibodies. Pre......-treatment with ibrutinib did not inhibit complement activation or complement-mediated lysis. In contrast, ibrutinib strongly inhibited all cell-mediated mechanisms induced by anti-CD20 antibodies rituximab, ofatumumab or obinutuzumab, either in purified systems or whole blood assays. Activation of natural killer cells...

Interactions between Ibrutinib and Anti-CD20 Antibodies: Competing Effects on the Outcome of Combination Therapy.

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Skarzynski, Martin; Niemann, Carsten U; Lee, Yuh Shan; Martyr, Sabrina; Maric, Irina; Salem, Dalia; Stetler-Stevenson, Maryalice; Marti, Gerald E; Calvo, Katherine R; Yuan, Constance; Valdez, Janet; Soto, Susan; Farooqui, Mohammed Z H; Herman, Sarah E M; Wiestner, Adrian

2016-01-01

Clinical trials of ibrutinib combined with anti-CD20 monoclonal antibodies (mAb) for chronic lymphocytic leukemia (CLL) report encouraging results. Paradoxically, in preclinical studies, in vitro ibrutinib was reported to decrease CD20 expression and inhibit cellular effector mechanisms. We therefore set out to investigate effects of in vivo ibrutinib treatment that could explain this paradox. Patients received single-agent ibrutinib (420 mg daily) on an investigator-initiated phase II trial. Serial blood samples were collected pretreatment and during treatment for ex vivo functional assays to examine the effects on CLL cell susceptibility to anti-CD20 mAbs. We demonstrate that CD20 expression on ibrutinib was rapidly and persistently downregulated (median reduction 74%, day 28, P ibrutinib were less susceptible to anti-CD20 mAb-mediated complement-dependent cytotoxicity than pretreatment cells (median reduction 75%, P ibrutinib, providing a likely mechanism for the preserved C3d opsonization. In addition, ibrutinib significantly inhibited trogocytosis, a major contributor to antigen loss and tumor escape during mAb therapy. Our data indicate that ibrutinib promotes both positive and negative interactions with anti-CD20 mAbs, suggesting that successfully harnessing maximal antitumor effects of such combinations requires further investigation. ©2015 American Association for Cancer Research.

GP2 is selectively expressed by small intestinal CD103⁺CD11b⁺ cDC

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Müller-Luda, Katarzyna; Ahmadi, Fatemeh; Ohno, Hiroshi

DC in the small intestine. Moreover, GP2 expressing cDC in the small intestine were dramatically reduced in the setting of intestinal inflammation. We have previously shown that mice with an IRF4 deletion in CD11c+ cells (Cd11c-cre.Irf4 fl/fl mice) have reduced numbers of small intestinal CD103+CD11b+ c......DC. Interesting, we found that GP2+ CD103+CD11b+ cDC were dramatically reduced in these mice. Finally, to address the in vivo role of GP2 expression by cDC, we have generated mice with a selective deletion of GP2 in CD103+CD11b+ cDC (huLangerin-cre.gp2 fl/fl  mice). Results from these ongoing studies...

Anti-inflammatory and anti-chemotactic effects of dietary flaxseed oil on CD8(+) T cell/adipocyte-mediated cross-talk.

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Monk, Jennifer M; Liddle, Danyelle M; Brown, Morgan J; Zarepoor, Leila; De Boer, Anna A; Ma, David W L; Power, Krista A; Robinson, Lindsay E

2016-03-01

CD8(+) T cell/adipocyte paracrine interactions represent a critical step in the development of the obese inflammatory phenotype that is disrupted by long-chain n-3 PUFA. Our objective was to determine the effect of flaxseed-derived n-3 PUFA (α-linolenic acid) on these paracrine interactions. C57BL/6 mice were fed 3.5% flaxseed oil (FX) + 3.5% corn oil diet w/w or an isocaloric 7% corn oil w/w control diet (CON) for 3 wk. 3T3-L1 adipocytes and purified primary splenic CD8(+) T cells were cocultured at an obese cellular ratio (10% CD8(+) T cells) and LPS-stimulated (10 ng/mL mimicking obese circulating endotoxin levels) for 24 h. FX cocultures reduced (i) secreted IL-6, tumor necrosis factor α (TNF-α), macrophage chemoattractant protein 1 (MCP-1), macrophage inflammatory protein 1α (MIP-1α), and RANTES (regulated on activation, normal T cell expressed and secreted) levels; (ii) activation of inflammatory transcription factors NFκB (nuclear factor kappa-light-chain-enhancer of activated B cell) p65 and signal transducer and activator of transcription-3 (STAT3); and (iii) RAW264.7 macrophage chemotaxis versus CON (p ≤ 0.05). Coculture of pre-inflamed adipocytes (10 ng/mL LPS, 24 h prior to CD8(+) T-cell addition) resulted in reduced secretion of IL-6, IL-1β, MCP-1, MCP-3, MIP-1β, and RANTES in FX cocultures versus CON (p ≤ 0.05). FX exerts an anti-chemotactic and anti-inflammatory effect on CD8(+) T cell/adipocyte paracrine interactions (cross-talk), which has the potential to mitigate macrophage chemotaxis which drives components of the obese phenotype. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Contribution of herpesvirus specific CD8 T cells to anti-viral T cell response in humans.

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Elena Sandalova

Full Text Available Herpesviruses infect most humans. Their infections can be associated with pathological conditions and significant changes in T cell repertoire but evidences of symbiotic effects of herpesvirus latency have never been demonstrated. We tested the hypothesis that HCMV and EBV-specific CD8 T cells contribute to the heterologous anti-viral immune response. Volume of activated/proliferating virus-specific and total CD8 T cells was evaluated in 50 patients with acute viral infections: 20 with HBV, 12 with Dengue, 12 with Influenza, 3 with Adenovirus infection and 3 with fevers of unknown etiology. Virus-specific (EBV, HCMV, Influenza pentamer+ and total CD8 T cells were analyzed for activation (CD38/HLA-DR, proliferation (Ki-67/Bcl-2(low and cytokine production. We observed that all acute viral infections trigger an expansion of activated/proliferating CD8 T cells, which differs in size depending on the infection but is invariably inflated by CD8 T cells specific for persistent herpesviruses (HCMV/EBV. CD8 T cells specific for other non-related non persistent viral infection (i.e. Influenza were not activated. IL-15, which is produced during acute viral infections, is the likely contributing mechanism driving the selective activation of herpesvirus specific CD8 T cells. In addition we were able to show that herpesvirus specific CD8 T cells displayed an increased ability to produce the anti-viral cytokine interferon-gamma during the acute phase of heterologous viral infection. Taken together, these data demonstrated that activated herpesvirus specific CD8 T cells inflate the activated/proliferating CD8 T cells population present during acute viral infections in human and can contribute to the heterologous anti-viral T cell response.

Mass-Production and Characterization of Anti-CD20 Monoclonal Antibody in Peritoneum of Balb/c Mice

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Leili Aghebati

2013-02-01

Full Text Available Purpose: Monoclonal antibodies are important tools are used in basic research as well as, in diagnosis, imaging and treatment of immunodeficiency diseases, infections and cancers. The purpose of this study was to produce large scale of monoclonal antibody against CD20 in order to diagnostic application in leukemia and lymphomas disorders. Methods: Hybridoma cells that produce monoclonal antibody against human CD20 were administered into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. After twelve days, approximately 7 ml ascetic fluid was harvested from the peritoneum of each mouse. Evaluation of mAb titration was assessed by ELISA method. In the present study, we describe a protocol for large scale production of MAbs. Results: We prepared monoclonal antibodies (mAbs with high specificity and sensitivity against human CD20 by hybridoma method and characterized them by ELISA. The subclass of antibody was IgG2a and its light chain was kappa. Ascetic fluid was purified by Protein-A Sepharose affinity chromatography and the purified monoclonal antibody was conjugated with FITC and Immunofluorescence was done for confirming the specific binding. Conclusion: The conjugated monoclonal antibody could have application in diagnosis B-cell lymphomas, hairy cell leukemia, B-cell chronic lymphocytic leukemia, and melanoma cancer stem cells.

Mass-Production and Characterization of Anti-CD20 Monoclonal Antibody in Peritoneum of Balb/c Mice

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Sineh sepehr, Koushan; Baradaran, Behzad; Majidi, Jafar; Abdolalizadeh, Jalal; Aghebati, leili; Zare Shahneh, Fatemeh

2013-01-01

Purpose: Monoclonal antibodies are important tools are used in basic research as well as, in diagnosis, imaging and treatment of immunodeficiency diseases, infections and cancers. The purpose of this study was to produce large scale of monoclonal antibody against CD20 in order to diagnostic application in leukemia and lymphomas disorders. Methods: Hybridoma cells that produce monoclonal antibody against human CD20 were administered into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. After twelve days, approximately 7 ml ascetic fluid was harvested from the peritoneum of each mouse. Evaluation of mAb titration was assessed by ELISA method. In the present study, we describe a protocol for large scale production of MAbs. Results: We prepared monoclonal antibodies (mAbs) with high specificity and sensitivity against human CD20 by hybridoma method and characterized them by ELISA. The subclass of antibody was IgG2a and its light chain was kappa. Ascetic fluid was purified by Protein-A Sepharose affinity chromatography and the purified monoclonal antibody was conjugated with FITC and Immunofluorescence was done for confirming the specific binding. Conclusion: The conjugated monoclonal antibody could have application in diagnosis B-cell lymphomas, hairy cell leukemia, B-cell chronic lymphocytic leukemia, and melanoma cancer stem cells. PMID:24312821

Standardization of methodology to derivatization and radiolabeling of the anti-CD20 monoclonal antibody from bifunctional chelator DOTA-NHS-Ester

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Massicano, Adriana V.F.; Akanji, Akinkunmi G.; Santos, Josefina S.; Pujatti, Priscilla B.; Couto, Renata M.; Massicano, Felipe; Araujo, Elaine Bortoleti de

2009-01-01

Lymphomas are cancers of the lymphatic system, being the most common the non-Hodgkin lymphoma (NHL). The Radioimmunotherapy (RIT), that increase the cytotoxic effect of monoclonal antibodies (mAb), therefore labeling these Mab with different radioisotopes. RIT combines the specificity of the antibody and the toxicity of the radionuclides. The mAb anti-CD20 is used for treatment of relapse or refractory NHL. The labeling of anti- CD20 with 177 Lu, requires a bifunctional chelating agent that is designed to make a 'connect bridge' between the mAb and the radionuclide. The incorporation of the chelating group in mAb structure is called derivatization. The aim of this work is to study the derivatization of anti-CD20 antibody with DOTA-NHS-ester chelating group and labeling parameters to produce 177 Lu-DOTA-Anti CD20. Five milligrams of anti-CD20 were purified by dialysis against phosphate buffer pH 8.0 and derivatized with DOTA-NHS-ester in 1:250, 1:500 and 1:1000 molar ratios. The reaction was conducted for 1 hour in gently mixing at room temperature and remained under refrigeration for 48 hours. The reaction mixture was purified in gel column Sephadex G-50 ; the aliquots that presented greater protein concentration, were mixed and concentrated. The purified antibody conjugated was added to 111-185MBq (3-5mCi) of 177 LuCl3 diluted in 0.4 M acetate buffer pH 5.5. Radiochemical purity was less than 95% in all the molar ratios, indicating necessity of the purification after the labeling. The mAb derivatized showed stable when stored for to 1 month to 4 deg C and 4 days at -20 deg C. (author)

Cloning analysis of HBV-specific CD8 T cell receptor gene in patients with acute hepatitis B

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Ning DING

2011-05-01

Full Text Available Objective To investigate the molecular mechanism of T cell receptor(TCR in CD8 T cell-mediated immune response to HBV in patients with acute hepatitis B(AHB.Methods Peripheral blood mononuclear cells(PBMCs were collected from HLA-A2-positive AHB patients.To determine HBsAg183-191 and HBsAg335-343-specific CD8 T cell frequencies,the PBMCs were stained by fluorescence-labeled anti-CD3,anti-CD8 and pentamers,and analyzed by flow cytometry.PBMCs from 6 patients were stimulated with epitopic peptide HBsAg335-343 in vitro for 3 to 4 weeks.HBV-specific CD8 T cells were isolated by magnetic activated cell sorting followed by flow florescence activated cell sorting.The mRNA of sorted cells was extracted after expanding by IL-2,anti-CD3 and anti-CD8.The full-length gene fragments of variable region of TCR α and β chains were gained by 5’-RACE,and then cloned and sequenced(≥50 clones for single chain of each sample.The gene families of TCR α and β chains were identified and the sequence characters of CDR3 were compared.Results Analysis of more than 600 cloned gene sequences of TCR α and β chains showed that the proliferated HBV-specific CD8 T cells from 6 AHB patients presented a predominant expression in TCR α and chains,with 2-4 α chain families and 1-4 chain families in each case.The α2,α14,α15,β3,β13 and 23 families were detected in more than one case.The chain genes were all 13 for all tested clones in one case.For the same α chain or-chain family,CDR3 sequences tended to be identical in one case but different among cases.Conclusions HBV-specific CD8 T cells with antigenic peptide-induced proliferation present predominance in the usage of TCR α and β chains.This property might be one of the important molecular factors influencing anti-HBV immunity.

Enhanced efficacy of gemcitabine in combination with anti-CD20 monoclonal antibody against CD20+ non-Hodgkin's lymphoma cell lines in vitro and in scid mice

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Jin Fang

2005-08-01

Full Text Available Abstract Background Despite exciting new targeted therapeutics against non-Hodgkin's lymphoma (NHL, chemotherapy remains a cornerstone of therapy. While purine nucleoside analogs have significant activity in low grade NHL, the pyrimidine nucleoside analog gemcitabine has been less extensively studied, but has important activity. Use of the anti-CD20 monoclonal antibody rituximab in combination with chemotherapy for B-NHL is becoming prevalent in clinical practice, but has not been extensively studied in pre-clinical models. Methods We have tested the activity of gemcitabine ± rituximab in vitro and in scid/human NHL xenograft models. We used two t(14;18+, CD20+ follicular B cell NHL cell lines, DoHH2 a transformed NHL line and WSU-FSCCL isolated from pleural fluid of a patient with indolent NHL. Results Gemcitabine is cytotoxic to DoHH2 and WSU-FSCCL cells in vitro, and the IC50 is 2–3 fold lower in the presence of rituximab. Apoptosis is also enhanced in the presence of rituximab. Clearance of NHL cells from ascites in scid mice is prolonged by the combination, as compared with either agent alone. Most importantly, survival of scid mice bearing human NHL cells is significantly prolonged by the combination of gemcitabine + rituximab. Conclusion Based on our pre-clinical data showing prolonged survival of mice bearing human lymphoma cell line xenografts after treatment with gemcitabine + anti-CD20 antibody, this combination, expected to have non-overlapping toxicity profiles, should be explored in clinical trials.

[Regulatory B cells activated by CpG-ODN combined with anti-CD40 monoclonal antibody inhibit CD4(+)T cell proliferation].

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Wang, Keng; Tao, Lei; Su, Jianbing; Zhang, Yueyang; Zou, Binhua; Wang, Yiyuan; Li, Xiaojuan

2016-09-01

Objective To observe the immunosuppressive function of regulatory B cells (Bregs) in vitro after activated by CpG oligodeoxynucleotide (CpG-ODN) and anti-CD40 mAb. Methods Mice splenic CD5(+)CD1d(high)B cells and CD5(-)CD1d(low)B cells were sorted by flow cytometry. These B cells were first stimulated with CpG-ODN combined with anti-CD40 mAb for 24 hours, and then co-cultured with purified CD4(+)T cells. The interleukin 10 (IL-10) expression in the activated Bregs and other B cell subset, as well as the proliferation and interferon γ (IFN-γ) expression in the CD4(+) T cells activated by anti-CD3 mAb plus anti-CD28 mAb were determined by flow cytometry. Results CD5(+)CD1d(high) B cells activated by CpG-ODN plus anti-CD40 mAb blocked the up-regulated CD4(+)T proliferation and significantly reduced the IFN-γ level. At the same time, activated CD5(-)CD1d(low)B cells showed no inhibitory effect on CD4(+)T cells. Further study revealed that IL-10 expression in the CD5(+)CD1d(high) B cells were much higher than that in the CD5(-)CD1d(low)B cells after stimulated with CpG-ODN combined with anti-CD40 mAb for 24 hours. Conclusion CD5(+)CD1d(high) B cells activated by CpG-ODN combined with anti-CD40 mAb have immune inhibitory effects on CD4(+)T cell activation in vitro , which possibly due to IL-10 secretion.

Anti-leukemic activity and tolerability of anti-human CD47 monoclonal antibodies

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Pietsch, E C; Dong, J; Cardoso, R; Zhang, X; Chin, D; Hawkins, R; Dinh, T; Zhou, M; Strake, B; Feng, P-H; Rocca, M; Santos, C Dos; Shan, X; Danet-Desnoyers, G; Shi, F; Kaiser, E; Millar, H J; Fenton, S; Swanson, R; Nemeth, J A; Attar, R M

2017-01-01

CD47, a broadly expressed cell surface protein, inhibits cell phagocytosis via interaction with phagocyte-expressed SIRPα. A variety of hematological malignancies demonstrate elevated CD47 expression, suggesting that CD47 may mediate immune escape. We discovered three unique CD47-SIRPα blocking anti-CD47 monoclonal antibodies (mAbs) with low nano-molar affinity to human and cynomolgus monkey CD47, and no hemagglutination and platelet aggregation activity. To characterize the anti-cancer activity elicited by blocking CD47, the mAbs were cloned into effector function silent and competent Fc backbones. Effector function competent mAbs demonstrated potent activity in vitro and in vivo, while effector function silent mAbs demonstrated minimal activity, indicating that blocking CD47 only leads to a therapeutic effect in the presence of Fc effector function. A non-human primate study revealed that the effector function competent mAb IgG1 C47B222-(CHO) decreased red blood cells (RBC), hematocrit and hemoglobin by >40% at 1 mg/kg, whereas the effector function silent mAb IgG2σ C47B222-(CHO) had minimal impact on RBC indices at 1 and 10 mg/kg. Taken together, our findings suggest that targeting CD47 is an attractive therapeutic anti-cancer approach. However, the anti-cancer activity observed with anti-CD47 mAbs is Fc effector dependent as are the side effects observed on RBC indices. PMID:28234345

Ibrutinib interferes with the cell-mediated anti-tumor activities of therapeutic CD20 antibodies: implications for combination therapy

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Roit, Fabio Da; Engelberts, Patrick J.; Taylor, Ronald P.; Breij, Esther C.W.; Gritti, Giuseppe; Rambaldi, Alessandro; Introna, Martino; Parren, Paul W.H.I.; Beurskens, Frank J.; Golay, Josée

2015-01-01

The novel Bruton tyrosine kinase inhibitor ibrutinib and phosphatidyl-4-5-biphosphate 3-kinase-δ inhibitor idelalisib are promising drugs for the treatment of chronic lymphocytic leukemia and B-cell non-Hodgkin lymphoma, either alone or in combination with anti-CD20 antibodies. We investigated the possible positive or negative impact of these drugs on all known mechanisms of action of both type I and type II anti-CD20 antibodies. Pretreatment with ibrutinib for 1 hour did not increase direct cell death of cell lines or chronic lymphocytic leukemia samples mediated by anti-CD20 antibodies. Pre-treatment with ibrutinib did not inhibit complement activation or complement-mediated lysis. In contrast, ibrutinib strongly inhibited all cell-mediated mechanisms induced by anti-CD20 antibodies rituximab, ofatumumab or obinutuzumab, either in purified systems or whole blood assays. Activation of natural killer cells, and antibody-dependent cellular cytotoxicity by these cells, as well as phagocytosis by macrophages or neutrophils were inhibited by ibrutinib with a half maximal effective concentration of 0.3–3 μM. Analysis of anti-CD20 mediated activation of natural killer cells isolated from patients on continued oral ibrutinib treatment suggested that repeated drug dosing inhibits these cells in vivo. Finally we show that the phosphatidyl-4-5-biphosphate 3-kinase-δ inhibitor idelalisib similarly inhibited the immune cell-mediated mechanisms induced by anti-CD20 antibodies, although the effects of this drug at 10 μM were weaker than those observed with ibrutinib at the same concentration. We conclude that the design of combined treatment schedules of anti-CD20 antibodies with these kinase inhibitors should consider the multiple negative interactions between these two classes of drugs. PMID:25344523

Anti-inflammatory drugs interacting with Zn(II), Cd(II) and Pt(II) metal ions.

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Dendrinou-Samara, C; Tsotsou, G; Ekateriniadou, L V; Kortsaris, A H; Raptopoulou, C P; Terzis, A; Kyriakidis, D A; Kessissoglou, D P

1998-09-01

Complexes of Zn(II), Cd(II) and Pt(II) metal ions with the anti-inflammatory drugs, 1-methyl-5-(p-toluoyl)-1H-pyrrole-2-acetic acid (Tolmetin), alpha-methyl-4-(2-methylpropyl)benzeneacetic acid (Ibuprofen), 6-methoxy-alpha-methylnaphthalene-2-acetic acid (Naproxen) and 1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indole-3-acetic acid (indomethacin) have been synthesized and characterized. In the structurally characterized Cd(naproxen)2 complex the anti-inflammatory drugs acts as bidentate chelate ligand coordinatively bound to metal ions through the deprotonated carboxylate group. Crystal data for 1: [C32H26O8Cd], orthorhombic, space group P22(1)2(1), a = 5.693(2) (A), b = 8.760(3) (A), c = 30.74(1) (A), V = 1533(1) A3, Z = 2. Antibacterial and growth inhibitory activity is higher than that of the parent ligands or the platinum(II) diamine compounds.

Development of 177Lu-DOTA-anti-CD20 for radioimmunotherapy

International Nuclear Information System (INIS)

Hassan Yousefnia; Amir Reza Jalilian; Ali Bahrami-Samani; Simindokht Shirvani-Arani; Mohammad Ghannadi-Maragheh; Azim Arbabi; Edalat Radfar

2011-01-01

Rituximab was successively labeled with 177 Lu-lutetium chloride. 177 Lu chloride was obtained by thermal neutron flux (4 x 1013 n cm -2 s -1 ) of natural Lu 2 O 3 sample with a specific activity of 2.6-3 GBq/mg. The macrocyclic bifunctional chelating agent, N-succinimidyl-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA-NHS) was prepared at 25 deg C using DOTA, N-hydroxy succinimide (NHS) in CH 2 Cl 2 . DOTA-rituximab was obtained by the addition of 1 mL of a rituximab pharmaceutical solution (5 mg/mL, in phosphate buffer, pH 7.8) to a glass tube pre-coated with DOTA-NHS (0.01-0.1 mg) at 25 deg C with continuous mild stirring for 15 h. Radiolabeling was performed at 37 deg C in 24 h. Radio-thin layer chromatography showed an overall radiochemical purity of >98% at optimized conditions (specific activity = 444 MBq/mg, labeling efficacy; 82%). The final isotonic 177 Lu-DOTA-rituximab complex was checked by gel electrophoresis for structure integrity control. Radio-TLC was performed to ensure that only one species was present after filtration through a 0.22 μm filter. Preliminary biodistribution studies in normal rats were carried out to determine complex distribution of the radioimmunoconjugate up to 168 h. The biodistribution data were in accordance with other antiCD20 radioimmunoconjugates already reported. (author)

Labeling an anti-CD20 monoclonal antibody with 90Y

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Perera Pintado, Alejandro; Leyva Montaña, René; Prats Capote, Anaís; Góngora Bravo, Magdiel; Alberti Ramírez, Alejandro; León, Mariela; Hernández González, Ignacio; Dorvignit, Denise

2016-01-01

Lymphomas are among the 10 leading causes of death, both in Cuba and in the world, with an increasing incidence in recent years. Follicular lymphoma low-grade (indolent) is one of the most common in the Western world, representing 1/3 of all non-Hodgkin lymphomas (NHL). More than 90% of patients present with disseminated disease at diagnosis and generally have a slow evolution and good response to conventional treatment; but radically changed its forecast to relapse, resistance to therapeutic and histologic transformation can occur. The monoclonal antibody therapy has been a promising therapeutic. In this respect CD20 antigen it has been considered one of the most attractive targets in the therapy of follicular B cell lymphoma This is expressed in more than 90% of cases, while not present in stem cells and lines progenitors. Despite the success of immunotherapy, the relapse rate is still considerable. In order to increase the cytotoxic potential of immunotherapy, marked with beta emitting radionuclides alpha particles or monoclonal antibodies are used today. Despite encouraging results in patients with non-Hodgkin lymphomas refractory to other treatments, the extremely high costs of these commercial radiopharmaceuticals have greatly limited its application, even in the first world. A sustainable alternative is the marking of other anti-CD20 monoclonal antibodies, so researchers from several countries have concentrated their efforts on rituximaby other similar antibodies labeled with therapeutic radionuclides, as a possible cost-effectively to more problem. Today in Cuba it has an electrolytic generator 90 Sr- 90 Y Isotope Center, which ensures the availability of the radionuclide. In addition, the chimeric MAb rituximab is applied as part of the therapy of NHL in its health system and, recently, the Center for Molecular Immunology has obtained a chimeric monoclonal anti-CD20 antibody biosimilar rituximab, which is in phase clinical trial; which opens prospects for

Empty conformers of HLA-B preferentially bind CD8 and regulate CD8+ T cell function.

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Geng, Jie; Altman, John D; Krishnakumar, Sujatha; Raghavan, Malini

2018-05-09

When complexed with antigenic peptides, human leukocyte antigen (HLA) class I (HLA-I) molecules initiate CD8 + T cell responses via interaction with the T cell receptor (TCR) and co-receptor CD8. Peptides are generally critical for the stable cell surface expression of HLA-I molecules. However, for HLA-I alleles such as HLA-B*35:01, peptide-deficient (empty) heterodimers are thermostable and detectable on the cell surface. Additionally, peptide-deficient HLA-B*35:01 tetramers preferentially bind CD8 and to a majority of blood-derived CD8 + T cells via a CD8-dependent binding mode. Further functional studies reveal that peptide-deficient conformers of HLA-B*35:01 do not directly activate CD8 + T cells, but accumulate at the immunological synapse in antigen-induced responses, and enhance cognate peptide-induced cell adhesion and CD8 + T cell activation. Together, these findings indicate that HLA-I peptide occupancy influences CD8 binding affinity, and reveal a new set of regulators of CD8 + T cell activation, mediated by the binding of empty HLA-I to CD8. © 2018, Geng et al.

Memory B cells and CD8⁺ lymphocytes do not control seasonal influenza A virus replication after homologous re-challenge of rhesus macaques.

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Timothy D Carroll

Full Text Available This study sought to define the role of memory lymphocytes in the protection from homologous influenza A virus re-challenge in rhesus macaques. Depleting monoclonal antibodies (mAb were administered to the animals prior to their second experimental inoculation with a human seasonal influenza A virus strain. Treatment with either anti-CD8α or anti-CD20 mAbs prior to re-challenge had minimal effect on influenza A virus replication. Thus, in non-human primates with pre-existing anti-influenza A antibodies, memory B cells and CD8α⁺ T cells do not contribute to the control of virus replication after re-challenge with a homologous strain of influenza A virus.

2B4-SAP signaling is required for the priming of naive CD8+ T cells by antigen-expressing B cells and B lymphoma cells.

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Huang, Yu-Hsuan; Tsai, Kevin; Tan, Sara Y; Kang, Sohyeong; Ford, Mandy L; Harder, Kenneth W; Priatel, John J

2017-01-01

Mutations in SH2D1A gene that encodes SAP (SLAM-associated protein) result in X-linked lymphoproliferative disease (XLP), a rare primary immunodeficiency disease defined by exquisite sensitivity to the B-lymphotropic Epstein-Barr virus (EBV) and B cell lymphomas. However, the precise mechanism of how the loss of SAP function contributes to extreme vulnerability to EBV and the development of B cell lymphomas remains unclear. Here, we investigate the hypothesis that SAP is critical for CD8 + T cell immune surveillance of antigen (Ag)-expressing B cells or B lymphoma cells under conditions of defined T cell receptor (TCR) signaling. Sh2d1a - / - CD8 + T cells exhibited greatly diminished proliferation relative to wild type when Ag-presenting-B cells or -B lymphoma cells served as the primary Ag-presenting cell (APC). By contrast, Sh2d1a - / - CD8 + T cells responded equivalently to wild-type CD8 + T cells when B cell-depleted splenocytes, melanoma cells or breast carcinoma cells performed Ag presentation. Through application of signaling lymphocyte activation molecule (SLAM) family receptor blocking antibodies or SLAM family receptor-deficient CD8 + T cells and APCs, we found that CD48 engagement on the B cell surface by 2B4 is crucial for initiating SAP-dependent signaling required for the Ag-driven CD8 + T cell proliferation and differentiation. Altogether, a pivotal role for SAP in promoting the expansion and differentiation of B cell-primed viral-specific naive CD8 + T cells may explain the selective immune deficiency of XLP patients to EBV and B cell lymphomas.

2B4-SAP signaling is required for the priming of naive CD8+ T cells by antigen-expressing B cells and B lymphoma cells

Science.gov (United States)

2017-01-01

ABSTRACT Mutations in SH2D1A gene that encodes SAP (SLAM-associated protein) result in X-linked lymphoproliferative disease (XLP), a rare primary immunodeficiency disease defined by exquisite sensitivity to the B-lymphotropic Epstein–Barr virus (EBV) and B cell lymphomas. However, the precise mechanism of how the loss of SAP function contributes to extreme vulnerability to EBV and the development of B cell lymphomas remains unclear. Here, we investigate the hypothesis that SAP is critical for CD8+ T cell immune surveillance of antigen (Ag)-expressing B cells or B lymphoma cells under conditions of defined T cell receptor (TCR) signaling. Sh2d1a−/− CD8+ T cells exhibited greatly diminished proliferation relative to wild type when Ag-presenting-B cells or -B lymphoma cells served as the primary Ag-presenting cell (APC). By contrast, Sh2d1a−/− CD8+ T cells responded equivalently to wild-type CD8+ T cells when B cell-depleted splenocytes, melanoma cells or breast carcinoma cells performed Ag presentation. Through application of signaling lymphocyte activation molecule (SLAM) family receptor blocking antibodies or SLAM family receptor-deficient CD8+ T cells and APCs, we found that CD48 engagement on the B cell surface by 2B4 is crucial for initiating SAP-dependent signaling required for the Ag-driven CD8+ T cell proliferation and differentiation. Altogether, a pivotal role for SAP in promoting the expansion and differentiation of B cell-primed viral-specific naive CD8+ T cells may explain the selective immune deficiency of XLP patients to EBV and B cell lymphomas. PMID:28344876

Anti-CD25 mAb administration prevents spontaneous liver transplant tolerance.

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Li, W; Carper, K; Liang, Y; Zheng, X X; Kuhr, C S; Reyes, J D; Perkins, D L; Thomson, A W; Perkins, J D

2006-12-01

Liver allografts are accepted spontaneously in all mouse strain combinations without immunosuppressive therapy. The mechanisms underlying this phenomenon remain largely undefined. In this study, we examined the effect of CD4+ CD25+ T regulatory cells (Treg) on the induction of mouse liver transplant tolerance. Orthotopic liver transplantation was performed from B10 (H2b) to C3H (H2k) mice. Depleting rat anti-mouse CD25 mAb (PC61) was given to the donors or recipients (250 microg/d IP) pretransplant or to the recipients postoperatively. At day 5 posttransplantation, both effector T cells (mainly CD8) and CD4+ CD25+ Treg were increased in the liver allografts and host spleens compared to naïve mice. Anti-CD25 mAb administration, either pretransplantation or posttransplantation, reduced the ratio of CD4+ CD25+ Treg to the CD3 T cells of liver grafts and recipient spleens and induced liver allograft acute rejection compared to IgG treatment. Anti-CD25 mAb administration elevated anti-donor T-cell proliferative responses and CTL and NK activities of graft infiltrates and host splenocytes; reduced CTLA4, Foxp3, and IDO mRNA levels; increased IL-10 and IFN-gamma; and decreased IL-4 mRNA levels in the livers or host spleens. The number of apoptotic T cells was reduced significantly in the liver grafts and treated host spleens. Therefore, anti-CD25 mAb administration changed the balance of CD4+ CD25+ Treg to activated T cells of liver graft recipients, preventing liver transplant tolerance. This was associated with enhanced anti-donor immune reactivity, downregulated Treg gene expression, and reduced T cell apoptosis in the grafts and host spleens.

Anti-CD20 Immunoglobulin G Radiolabeling with a 99mTc-Tricarbonyl Core: In Vitro and In Vivo Evaluations.

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Hélène Carpenet

Full Text Available In recent years, the diagnostic and therapeutic uses of radioisotopes have shown significant progress. Immunoglobulin (Ig appears to be a promising tracer, particularly due to its ability to target selected antigens. The main objective of this study is to optimize and assess an Ig radiolabeling method with Technetium 99m (99mTc, an attractive radioelement used widely for diagnostic imaging. Monoclonal anti-CD20 IgG was retained to study in vitro and in vivo radiolabeling impact. After IgG derivatization with 2-iminothiolane, IgG-SH was radiolabeled by an indirect method, using a 99mTc-tricarbonyl core. Radiolabeling stability was evaluated over 24h by thin-layer chromatography. IgG integrity was checked by sodium dodecyl sulfate-polyacrylamide gel electrophoresis coupled with Western blot and autoradiography. The radiolabeled Ig's immunoaffinity was assessed in vitro by a radioimmunoassay method and binding experiments with cells (EL4-hCD20 and EL4-WT. Biodistribution studies were performed in normal BALB/c mice. Tumor uptake was assessed in mice bearing EL4-hCD20 and EL4-WT subcutaneous xenografts. With optimized method, high radiolabeling yields were obtained (95.9 ± 3.5%. 99mTc-IgG-SH was stable in phosphate-buffered saline (4°C and 25°C and in serum (37°C, even if important sensitivity to transchelation was observed. IgG was not degraded by derivatization and radiolabeling, as shown by Western blot and autoradiography results. 99mTc-anti-CD20 IgG-SH immunoaffinity was estimated with Kd = 35 nM by both methods. In vivo biodistribution studies for 48h showed significant accumulation of radioactivity in plasma, liver, spleen, lungs and kidneys. Planar scintigraphy of mice bearing tumors showed a significant uptake of 99mTc-anti-CD20 IgG-SH in CD20+ tumor versus CD20- tumor. Radiolabeling of derivatized IgG with 99mTc-tricarbonyl was effective, stable and required few antibody amounts. This attractive radiolabeling method is "antibody safe

Radiolabeling of anti-CD20 with Re-188 for treatment of Non-Hodgkin's lymphoma: radiochemical control

International Nuclear Information System (INIS)

Dias, C.R.; Osso Junior, J.A.

2008-01-01

Radioimmunotherapy (RIT) uses target-specific monoclonal antibodies or fragments labeled with a radioactive isotope to combine humoral and radiolytic functions and has the advantage of targeting not only the cell to which the antibody is bound but also the surrounding tumor cells and microenvironment. The most successful clinical studies of RIT in patients with Non-Hodgkin's Lymphoma (NHL) have targeted CD20+ Bcell tumors. Antibody therapy directed against the CD20 antigen on the surface of B-cells is considered one of the first successful target-specific therapies in oncology. The radionuclide rhenium-188 ( 188 Re) is currently produced from the father nuclide 188 W through a transportable generator system. Because of its easy availability and suitable nuclear properties (E βMAX = 2.1 MeV, t1/2 = 16.9 h, E γ = 155 keV), this radionuclide is considered an attractive candidate for application as therapeutic agent and could be conveniently utilized for imaging and dosimetric purposes. The objective of this work is the optimization of direct radiolabeling method of anti-CD20 with 188 Re using a liquid formulation. Anti-CD20 was reduced by incubation with 2-mercaptoethanol at room temperature. The number of resulting free sulphydryl groups was assayed with Ellman's reagent. Optimization of radiolabeling was achieved by varying parameters: antibody mass, reducing agent mass, tartrate mass, stability and reaction time, 188 Re volume and activity. Radiochemical purity of 188 Re-anti-CD20 was evaluated using instant thin layer chromatography-silica gel (ITLC-SG). Quality control methods for evaluation of radiochemical purity showed good labeling yield of the antibody but further studies will be carried out in order to improve the labeling yields and consequently the specific activity of the product. (author)

CD8αα expression marks terminally differentiated human CD8+ T cells expanded in chronic viral infection

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Lucy Jane Walker

2013-08-01

Full Text Available The T cell co-receptor CD8αβ enhances T cell sensitivity to antigen, however studies indicate CD8αα has the converse effect and acts as a co-repressor. Using a combination of Thymic Leukaemia antigen (TL tetramer, which directly binds CD8αα, anti-CD161 and anti-Vα7.2 antibodies we have been able for the first time to clearly define CD8αα expression on human CD8 T cells subsets. In healthy controls CD8αα is most highly expressed by CD161 bright (CD161++ mucosal associated invariant T (MAIT cells, with CD8αα expression highly restricted to the TCR Vα7.2+ cells of this subset. We also identified CD8αα-expressing populations within the CD161 mid (CD161+ and negative (CD161- non-MAIT CD8 T cell subsets and show TL-tetramer binding to correlate with expression of CD8β at low levels in the context of maintained CD8α expression (CD8α+CD8βlow. In addition, we found CD161-CD8α+CD8βlow populations to be significantly expanded in the peripheral blood of HIV-1 and hepatitis B (mean of 47% and 40% of CD161- T cells respectively infected individuals. Such CD8αα expressing T cells are an effector-memory population (CD45RA-, CCR7-, CD62L- that express markers of activation and maturation (HLA-DR+, CD28-, CD27-, CD57+ and are functionally distinct, expressing greater levels of TNF-α and IFN-γ on stimulation and perforin at rest than their CD8α+CD8βhigh counterparts. Antigen-specific T cells in HLA-B*4201+HIV-1 infected patients are found within both the CD161-CD8α+CD8βhigh and CD161-CD8α+CD8βlow populations. Overall we have clearly defined CD8αα expressing human T cell subsets using the TL-tetramer, and have demonstrated CD161-CD8α+CD8βlow populations, highly expanded in disease settings, to co-express CD8αβ and CD8αα. Co-expression of CD8αα on CD8αβ T cells may impact on their overall function in-vivo and contribute to the distinctive phenotype of highly differentiated populations in HBV and HIV-1 infection.

T helper-independent activation of human CD8+ cells: the role of CD28 costimulation.

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Van Gool, S W; Zhang, Y; Kasran, A; de Boer, M; Ceuppens, J L

1996-07-01

The concept that activation of MHC class I-restricted CD8+ cells entirely depends on help from MHC class II-restricted CD4+ T cells has recently been supplemented with an alternative model in which CD8+ cells can directly be activated by MHC class I-expressing professional antigen-presenting cells (APC), which are able to deliver an accessory signal. The authors analysed the role of CD28-mediated costimulation for T helper cell-independent activation of purified human CD8+ T cells in two different in vitro models. Freshly isolated CD8+ cells could be activated (proliferation, IL-2 production and cytotoxic activity) by anti-CD3-presenting Fc gamma R+ mouse cells transfected with the human CD28 ligand, CD80, as the only accessory signal. On the other hand, activation of CD8+ cells by allogeneic MHC class I on EBV-transformed B cells, which express two different CD28 ligands, CD80 and CD86, also proceeded very efficiently (proliferation, cytotoxic activity and CD25 expression), but was either not, or only partially, blocked by anti-CD80 and anti-CD86 MoAb or CTLA-4Ig. This indicates that other costimulatory signals are also effective, and that CD28 triggering is not absolutely required for initial T-cell activation. CsA and CD80/CD86-blocking agents were synergistic in completely inhibiting activation of CD8+ cells in the MLR with allogeneic B-cell lines. This combination also induced non-responsiveness of CD8+ cells upon restimulation in the absence of blocking agents. Therefore, although professional APC can apparently provide multiple costimulatory signals for direct activation of CD8+ T cells, the signal derived from CD80/CD86 is unique in providing CsA-resistance.

IL-4 and IL-13 mediated down-regulation of CD8 expression levels can dampen anti-viral CD8⁺ T cell avidity following HIV-1 recombinant pox viral vaccination.

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Wijesundara, Danushka K; Jackson, Ronald J; Tscharke, David C; Ranasinghe, Charani

2013-09-23

We have shown that mucosal HIV-1 recombinant pox viral vaccination can induce high, avidity HIV-specific CD8(+) T cells with reduced interleukin (IL)-4 and IL-13 expression compared to, systemic vaccine delivery. In the current study how these cytokines act to regulate anti-viral CD8(+) T, cell avidity following HIV-1 recombinant pox viral prime-boost vaccination was investigated. Out of a panel of T cell avidity markers tested, only CD8 expression levels were found to be enhanced on, KdGag197-205 (HIV)-specific CD8(+) T cells obtained from IL-13(-/-), IL-4(-/-) and signal transducer and, activator of transcription of 6 (STAT6)(-/-) mice compared to wild-type (WT) controls following, vaccination. Elevated CD8 expression levels in this instance also correlated with polyfunctionality, (interferon (IFN)-γ, tumour necorsis factor (TNF)-α and IL-2 production) and the avidity of HIVspecific CD8(+) T cells. Furthermore, mucosal vaccination and vaccination with the novel adjuvanted IL-13 inhibitor (i.e. IL-13Rα2) vaccines significantly enhanced CD8 expression levels on HIV-specific CD8(+), T cells, which correlated with avidity. Using anti-CD8 antibodies that blocked CD8 availability on CD8(+), T cells, it was established that CD8 played an important role in increasing HIV-specific CD8(+) T cell avidity and polyfunctionality in IL-4(-/-), IL-13(-/-) and STAT6(-/-) mice compared to WT controls, following vaccination. Collectively, our data demonstrate that IL-4 and IL-13 dampen CD8 expression levels on anti-viral CD8(+) T cells, which can down-regulate anti-viral CD8(+) T cell avidity and, polyfunctionality following HIV-1 recombinant pox viral vaccination. These findings can be exploited to, design more efficacious vaccines not only against HIV-1, but many chronic infections where high, avidity CD8(+) T cells help protection. Copyright © 2013 Elsevier Ltd. All rights reserved.

Increased T cell proliferative responses to islet antigens identify clinical responders to anti-CD20 monoclonal antibody (rituximab) therapy in type 1 diabetes.

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Herold, Kevan C; Pescovitz, Mark D; McGee, Paula; Krause-Steinrauf, Heidi; Spain, Lisa M; Bourcier, Kasia; Asare, Adam; Liu, Zhugong; Lachin, John M; Dosch, H Michael

2011-08-15

Type 1 diabetes mellitus is believed to be due to the autoimmune destruction of β-cells by T lymphocytes, but a single course of rituximab, a monoclonal anti-CD20 B lymphocyte Ab, can attenuate C-peptide loss over the first year of disease. The effects of B cell depletion on disease-associated T cell responses have not been studied. We compare changes in lymphocyte subsets, T cell proliferative responses to disease-associated target Ags, and C-peptide levels of participants who did (responders) or did not (nonresponders) show signs of β-cell preservation 1 y after rituximab therapy in a placebo-controlled TrialNet trial. Rituximab decreased B lymphocyte levels after four weekly doses of mAb. T cell proliferative responses to diabetes-associated Ags were present at baseline in 75% of anti-CD20- and 82% of placebo-treated subjects and were not different over time. However, in rituximab-treated subjects with significant C-peptide preservation at 6 mo (58%), the proliferative responses to diabetes-associated total (p = 0.032), islet-specific (p = 0.048), and neuronal autoantigens (p = 0.005) increased over the 12-mo observation period. This relationship was not seen in placebo-treated patients. We conclude that in patients with type 1 diabetes mellitus, anti-B cell mAb causes increased proliferative responses to diabetes Ags and attenuated β-cell loss. The way in which these responses affect the disease course remains unknown.

Dynamic analysis of CD127 expression on memory CD8 T cells from patients with chronic hepatitis B during telbivudine treatment

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Lv Guocai

2010-08-01

Full Text Available Abstract Background Accumulating evidence supports the theory that expression of CD127 on CD8 T cells during the process of antiviral immune response indicates a subset of effect CD8 T cells that successfully develop into fully protective memory. CD8 T cells expression of CD127 may be used as a predictor to evaluate disease status in chronic viral infection. The aim of this study was to investigate the CD127 expression level on different subsets of CD8 T cell and explore the relationship between CD127 expression on CD8 memory T cells and serum hepatitis B virus (HBV DNA and hepatitis B e antigen (HBeAg levels in patients with chronic hepatitis B (CHB. We also aimed to investigate the CD127 expression pattern on CD8 memory T cells of CHB patients who were treated with Telbivudine. Methods/Results Twenty HBeAg-positive CHB patients were selected and treated with telbivudine 600 mg/day for 48 weeks. The memory CD8 T cells were characterized by expression of CD45RA and CD27 markers. CD127 expression on the CD8 T-cell surface was measured by four-colour flow cytometry. Our results showed that CD127 expression on memory CD8 T cells was reduced in CHB patients. There was a strong negative correlation between CD127 expression on memory CD8 T cells and serum HBV DNA and HBeAg levels in CHB patients. Moreover, successful antiviral therapy increased CD127 expression on CD8 memory T cells as well as on HBV-specific CD8 T cells in CHB patients. Conclusion These results suggest that diminished CD127 expression on CD8 memory T cells of CHB patients is a potential mechanism explaining cellular immune function impairment in CHB infection, and that CD127 expression on CD8 memory T cells is a useful indicator for evaluating the effects of anti-HBV therapy.

Sensitive Detection of the Natural Killer Cell-Mediated Cytotoxicity of Anti-CD20 Antibodies and Its Impairment by B-Cell Receptor Pathway Inhibitors

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Floyd Hassenrück

2018-01-01

Full Text Available The antibody-dependent cell-mediated cytotoxicity (ADCC of the anti-CD20 monoclonal antibodies (mAbs rituximab and obinutuzumab against the cell line Raji and isolated CLL cells and its potential impairment by kinase inhibitors (KI was determined via lactate dehydrogenase release or calcein retention, respectively, using genetically modified NK92 cells expressing CD16-176V as effector cells. Compared to peripheral blood mononuclear cells, recombinant effector cell lines showed substantial alloreactivity-related cytotoxicity without addition of mAbs but afforded determination of ADCC with reduced interassay variability. The cytotoxicity owing to alloreactivity was less susceptible to interference by KI than the ADCC of anti-CD20 mAbs, which was markedly diminished by ibrutinib, but not by idelalisib. Compared to rituximab, the ADCC of obinutuzumab against primary CLL cells showed approximately 30% higher efficacy and less interference with KI. Irreversible BTK inhibitors at a clinically relevant concentration of 1 μM only weakly impaired the ADCC of anti-CD20 mAbs, with less influence in combinations with obinutuzumab than with rituximab and by acalabrutinib than by ibrutinib or tirabrutinib. In summary, NK cell line-based assays permitted the sensitive detection of ADCC of therapeutic anti-CD20 mAbs against CLL cells and of the interference of KI with this important killing mechanism.

Natural CD8+25+ regulatory T cell-secreted exosomes capable of suppressing cytotoxic T lymphocyte-mediated immunity against B16 melanoma

International Nuclear Information System (INIS)

Xie, Yufeng; Zhang, Xueshu; Zhao, Tuo; Li, Wei; Xiang, Jim

2013-01-01

Highlights: •CD8 + 25 + regulatory T cells secrete tolerogenic exosomes. •CD8 + 25 + regulatory T cell-derived exosomes exhibit immunosuppressive effect. •CD8 + 25 + regulatory T cell-derived exosomes inhibit antitumor immunity. -- Abstract: Natural CD4 + 25 + and CD8 + 25 + regulatory T (Tr) cells have been shown to inhibit autoimmune diseases. Immune cells secrete exosomes (EXOs), which are crucial for immune regulation. However, immunomodulatory effect of natural Tr cell-secreted EXOs is unknown. In this study, we purified natural CD8 + 25 + Tr cells from C57BL/6 mouse naive CD8 + T cells, and in vitro amplified them with CD3/CD28 beads. EXOs (EXO Tr ) were purified from Tr cell’s culture supernatants by differential ultracentrifugation and analyzed by electron microscopy, Western blot and flow cytometry. Our data showed that EXO Tr had a “saucer” or round shape with 50–100 nm in diameter, contained EXO-associated markers LAMP-1 and CD9, and expressed natural Tr cell markers CD25 and GITR. To assess immunomodulatory effect, we i.v. immunized C57BL/6 mice with ovalbumin (OVA)-pulsed DCs (DC OVA ) plus Tr cells or EXO Tr , and then assessed OVA-specific CD8 + T cell responses using PE-H-2K b /OVA tetramer and FITC-anti-CD8 antibody staining by flow cytometry and antitumor immunity in immunized mice with challenge of OVA-expressing BL6–10 OVA melanoma cells. We demonstrated that DC OVA -stimulated CD8 + T cell responses and protective antitumor immunity significantly dropped from 2.52% to 1.08% and 1.81% (p OVA (p Tr , respectively. Our results indicate that natural CD8 + 25 + Tr cell-released EXOs, alike CD8 + 25 + Tr cells, can inhibit CD8 + T cell responses and antitumor immunity. Therefore, EXOs derived from natural CD4 + 25 + and CD8 + 25 + Tr cells may become an alternative for immunotherapy of autoimmune diseases

The CARD8 p.C10X mutation associates with a low anti-glycans antibody response in patients with Crohn's disease.

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Vasseur, Francis; Sendid, Boualem; Broly, Franck; Gower-Rousseau, Corinne; Sarazin, Aurore; Standaert-Vitse, Annie; Colombel, Jean-Frederic; Poulain, Daniel; Jouault, Thierry

2013-03-18

Crohn's disease (CD) is associated with elevated anti-glycans antibody response in 60% of CD patients, and 25% of healthy first-degree relatives (HFDRs), suggesting a genetic influence for this humoral response. In mice, anti-glucan antibody response depends on the NLRP3 inflammasome. Here, we explored the effect of mutated CARD8, a component of the inflammasome, on anti-glycans antibody response in human. The association between p.C10X mutation (rs2043211) of the CARD8 gene and the levels of anti-glycans antibody response was examined in 39 CD families. The family-based QTDT association test was used to test for the genetic association between CARD8 p.C10X mutation and anti-glycan antibodies in the pedigrees. The difference in antibody responses determined by ELISA was tested in a subgroup of CD probands (one per family) and in a subgroup of HFDRs using the Wilcoxon Kruskal Wallis non-parametric test. The QTDT familial transmission tests showed that the p.C10X mutation of CARD8 was significantly associated with lower levels of antibody to mannans and glucans but not chitin (p=0.024, p=0.0028 and p=0.577, for ASCA, ALCA and ACCA, respectively). These associations were independent of NOD2 and NOD1 genetic backgrounds. The p.C10X mutation significantly associated or displayed a trend toward lower ASCA and ALCA levels (p=0.038 and p=0.08, respectively) only in the subgroup of CD probands. Such associations were not significant for ACCA levels in both subgroups of CD probands and of HFDRs. Our results show that ASCA and ALCA but not ACCA levels are under the influence of CARD8 genotype. Alteration of CARD8, a component of inflammasome, is associated with lower levels of antibodies directed to mannans and glucans at least in CD patients.

Hepatitis C virus protects human B lymphocytes from Fas-mediated apoptosis via E2-CD81 engagement.

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Zhihui Chen

2011-04-01

Full Text Available HCV infection is often associated with B-cell regulatory control disturbance and delayed appearance of neutralizing antibodies. CD81 is a cellular receptor for HCV and can bind to HCV envelope protein 2 (E2. CD81 also participates to form a B cell costimulatory complex. To investigate whether HCV influences B cell activation and immune function through E2 -CD81 engagement, here, human Burkitt's lymphoma cell line Raji cells and primary human B lymphocytes (PHB were treated with HCV E2 protein and cell culture produced HCV particles (HCVcc, and then the related cell phenotypes were assayed. The results showed that both E2 and HCVcc triggered phosphorylation of IκBα, enhanced the expression of anti-apoptosis Bcl-2 family proteins, and protected Raji cells and PHB cells from Fas-mediated death. In addition, both E2 protein and HCVcc increased the expression of costimulatory molecules CD80, CD86 and CD81 itself, and decreased the expression of complement receptor CD21. The effects were dependent on E2-CD81 interaction on the cell surface, since CD81-silenced Raji cells did not respond to both treatments; and an E2 mutant that lose the CD81 binding activity, could not trigger the responses of both Raji cells and PHB cells. The effects were not associated with HCV replication in cells, for HCV pseudoparticle (HCVpp and HCVcc failed to infect Raji cells. Hence, E2-CD81 engagement may contribute to HCV-associated B cell lymphoproliferative disorders and insufficient neutralizing antibody production.

Multivalent system for therapy of non-Hod king lymphomas based on Anti-CD20 conjugated to gold nanoparticles; Sistema multivalente para terapia de linfomas no-Hodking basado en Anti-CD20 conjugado a nanoparticulas de oro

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Miranda O, R. M.

2014-07-01

In recent publications has been reported that gold nanoparticles have an effect in reducing the expression of the oncogene Bcl -2 and have a high biocompatibility , this is the importance for using gold nanoparticles for this work. The antibody CD20 is an antibody that specifically binds to that over expressed CD20 antigen on the cell membrane of B lymphoma cell non- Hodgkin (cell line Raji) behold the importance of combining this bio molecule to gold nanoparticles since they have a high specificity with CD20 positive cells , also to carry out the antigen- antibody immunological reactions triggered mediating cell lysis, possibly by cytotoxicity and apoptosis. Therefore, this system must have characteristics of both components to eliminate B cell non- Hodgkin lymphoma.In this work it was studied a multivalent system composed of gold nanoparticles and anti-CD20 antibody, the term multi valency refers to the number of biomolecules attached to the surface of the gold nanoparticle. The synthesis and characterization of the gold nanoparticles and the multivalent system was performed and the effect of the multivalent system on the expression of oncogene Bcl-2 (group of proteins associated with the apoptotic pathway) was evaluated. Characterization of raw materials and the multivalent system was performed using spectroscopic and microscopic techniques, this to verify structural changes in raw materials and thus confirm the formation of CD20 binding to the surface of the nanoparticle gold by the bond between gold and sulfur in the cysteines of CD20. Taking advantage that the metal nanoparticles have the optical property of surface plasmon resonance, the absorption of gold nanoparticles was measured on the UV-Vis as it is affected by the surface molecules bind to it, showing a bathochromic displacement effected. The hydrodynamic diameter of the gold nanoparticles was measured to verify that the antibody is bound to the surface; this evidence was complemented by micrographs

Type i CD20 antibodies recruit the B cell receptor for complement-dependent lysis of malignant B cells

DEFF Research Database (Denmark)

Engelberts, P. J.; Voorhorst, M.; Schuurman, J.

2016-01-01

. We hypothesized that CD20 Ab-induced clustering of the IgM or IgG BCR was involved in accessory CDC. Indeed, accessory CDC was consistently observed in B cell lines expressing an IgM BCR and in some cell lines expressing an IgG BCR, but it was absent in BCR- B cell lines. A direct relationship...... between BCR expression and accessory CDC was established by transfecting the BCR into CD20+ cells: OFA-F(ab')2 fragments were able to induce CDC in the CD20+BCR+ cell population, but not in the CD20+BCR- population. Importantly, OFA-F(ab')2 fragments were able to induce CDC ex vivo in malignant B cells...... isolated from patients with mantle cell lymphoma and Waldenström macroglobulinemia. In summary, accessory CDC represents a novel effector mechanism that is dependent on type I CD20 Ab-induced BCR clustering. Accessory CDC may contribute to the excellent capacity of type I CD20 Abs to induce CDC...

iNKT cells suppress the CD8+ T cell response to a murine Burkitt's-like B cell lymphoma.

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Ryan L Bjordahl

Full Text Available The T cell response to B cell lymphomas differs from the majority of solid tumors in that the malignant cells themselves are derived from B lymphocytes, key players in immune response. B cell lymphomas are therefore well situated to manipulate their surrounding microenvironment to enhance tumor growth and minimize anti-tumor T cell responses. We analyzed the effect of T cells on the growth of a transplantable B cell lymphoma and found that iNKT cells suppressed the anti-tumor CD8(+ T cell response. Lymphoma cells transplanted into syngeneic wild type (WT mice or Jalpha18(-/- mice that specifically lack iNKT cells grew initially at the same rate, but only the mice lacking iNKT cells were able to reject the lymphoma. This effect was due to the enhanced activity of tumor-specific CD8(+ T cells in the absence of iNKT cells, and could be partially reversed by reconstitution of iNKT cells in Jalpha 18(-/- mice. Treatment of tumor-bearing WT mice with alpha -galactosyl ceramide, an activating ligand for iNKT cells, reduced the number of tumor-specific CD8(+ T cells. In contrast, lymphoma growth in CD1d1(-/- mice that lack both iNKT and type II NKT cells was similar to that in WT mice, suggesting that type II NKT cells are required for full activation of the anti-tumor immune response. This study reveals a tumor-promoting role for iNKT cells and suggests their capacity to inhibit the CD8(+ T cell response to B cell lymphoma by opposing the effects of type II NKT cells.

Monocyte-derived dendritic cells are essential for CD8+ T cell activation and anti-tumor responses after local immunotherapy

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Sabine eKuhn

2015-11-01

Full Text Available Tumors harbor several populations of dendritic cells with the ability to prime tumor-specific T cells. However, these T cells mostly fail to differentiate into armed effectors and are unable to control tumor growth. We have previously shown that treatment with immunostimulatory agents at the tumor site can activate anti-tumor immune responses, and is associated with the appearance of a population of monocyte-derived dendritic cells in the tumor and tumor-draining lymph node. Here we use dendritic cell or monocyte depletion and monocyte transfer to show that these monocyte-derived dendritic cells are critical to the activation of anti-tumor immune responses. Treatment with the immunostimulatory agents Monosodium Urate crystals and Mycobacterium smegmatis induced the accumulation of monocytes in the draining lymph node, their upregulation of CD11c and MHCII, and expression of iNOS, TNFα and IL12p40. Blocking monocyte entry into the lymph node and tumor through neutralization of the chemokine CCL2 or inhibition of Colony Stimulating Factor-1 receptor signaling prevented the generation of monocyte-derived dendritic cells, the infiltration of tumor-specific T cells into the tumor, and anti-tumor responses. In a reciprocal fashion, monocytes transferred into mice depleted of CD11c+ cells were sufficient to rescue CD8+ T cell priming in lymph node and delay tumor growth. Thus monocytes exposed to the appropriate conditions become powerful activators of tumor-specific CD8+ T cells and anti-tumor immunity.

Analysis of changes in the percentage of B (CD19) and T (CD3) lymphocytes, nk cells, subsets CD4, CD8 in differentiated thyroid cancer patients treated with iodine-131

International Nuclear Information System (INIS)

Luo Quanyong; Yu Yongli; Chen Libo; Lu Hankui; Zhu Ruisen

2004-01-01

Objective: To evaluate the changes in the percentage of B (CD19) and T (CD3) lymphocytes, NK cells, subsets CD4, CD8 in patients with differentiated thyroid carcinoma (DTC) who received iodine-131 for therapeutic purposes. Methods: In this study, 102 DTC patients were divided into three groups. Group A, 8 cases received 1850 MBq of iodine-131 for the remnant thyroid ablation. Group B, 43 cases received 3700 MBq of iodine-131 for the treatment of cervical lymph node metastasis. Group C, 51 cases received 7400 MBq of iodine-131 for remote metastasis. All patients were in a hypothyroid state at the time of administration of iodine-131 and resumed L-thyroxine (2μg/Kg/day) 5 days after iodine-131 administration. The percentage of B and T lymphocytes, NK cells, subsets CD4, CD8 in peripheral blood were serially analyzed at baseline and at days 7, 30 and 90 after iodine-131 administration using a Coulter EPICS XL cytometer. Ten healthy individuals were used as a control group for lymphocyte subset values. Results: Comparing the basal lymphocyte subset levels in groups A, B and C with the control group, only NK cells showed significantly higher levels in patients than in controls (P=0.043). In group A, only the percentage of NK cells (P=0.031) and B cells (P =0.024) were reduced at day 7. In group B, a decrease in the percentage of NK cells at days 7(P=0.005), 30 (P=0.021) was observed, while a significant decrease in the percentage of B cells was only observed at day 7(P=0.006). Among T cells, only CD4+ was obviously affected, resulting in a reduction in the CD4+/CD8+ ratio at day 30 (P=0.034). In group C, patients showed a decrease in the percentage of NK cells at days 7 (P=0.023), 30 (P=0.006). A decrease in the percentage of both B and T lymphocytes was observed at days 7(P=0.020, 0.018 respectively), 30(P=0.041, 0.025 respectively). Among T cells, a decrease in the percentage of CD4+ and an increase in the percentage of CD8+ were observed, resulting in a marked

CD19 CAR-T cells of defined CD4+:CD8+ composition in adult B cell ALL patients.

Science.gov (United States)

Turtle, Cameron J; Hanafi, Laïla-Aïcha; Berger, Carolina; Gooley, Theodore A; Cherian, Sindhu; Hudecek, Michael; Sommermeyer, Daniel; Melville, Katherine; Pender, Barbara; Budiarto, Tanya M; Robinson, Emily; Steevens, Natalia N; Chaney, Colette; Soma, Lorinda; Chen, Xueyan; Yeung, Cecilia; Wood, Brent; Li, Daniel; Cao, Jianhong; Heimfeld, Shelly; Jensen, Michael C; Riddell, Stanley R; Maloney, David G

2016-06-01

T cells that have been modified to express a CD19-specific chimeric antigen receptor (CAR) have antitumor activity in B cell malignancies; however, identification of the factors that determine toxicity and efficacy of these T cells has been challenging in prior studies in which phenotypically heterogeneous CAR-T cell products were prepared from unselected T cells. We conducted a clinical trial to evaluate CD19 CAR-T cells that were manufactured from defined CD4+ and CD8+ T cell subsets and administered in a defined CD4+:CD8+ composition to adults with B cell acute lymphoblastic leukemia after lymphodepletion chemotherapy. The defined composition product was remarkably potent, as 27 of 29 patients (93%) achieved BM remission, as determined by flow cytometry. We established that high CAR-T cell doses and tumor burden increase the risks of severe cytokine release syndrome and neurotoxicity. Moreover, we identified serum biomarkers that allow testing of early intervention strategies in patients at the highest risk of toxicity. Risk-stratified CAR-T cell dosing based on BM disease burden decreased toxicity. CD8+ T cell-mediated anti-CAR transgene product immune responses developed after CAR-T cell infusion in some patients, limited CAR-T cell persistence, and increased relapse risk. Addition of fludarabine to the lymphodepletion regimen improved CAR-T cell persistence and disease-free survival. Immunotherapy with a CAR-T cell product of defined composition enabled identification of factors that correlated with CAR-T cell expansion, persistence, and toxicity and facilitated design of lymphodepletion and CAR-T cell dosing strategies that mitigated toxicity and improved disease-free survival. ClinicalTrials.gov NCT01865617. R01-CA136551; Life Science Development Fund; Juno Therapeutics; Bezos Family Foundation.

CD19 CAR–T cells of defined CD4+:CD8+ composition in adult B cell ALL patients

Science.gov (United States)

Turtle, Cameron J.; Hanafi, Laïla-Aïcha; Berger, Carolina; Gooley, Theodore A.; Cherian, Sindhu; Hudecek, Michael; Sommermeyer, Daniel; Melville, Katherine; Pender, Barbara; Budiarto, Tanya M.; Robinson, Emily; Steevens, Natalia N.; Chaney, Colette; Soma, Lorinda; Chen, Xueyan; Li, Daniel; Cao, Jianhong; Heimfeld, Shelly; Jensen, Michael C.; Riddell, Stanley R.; Maloney, David G.

2016-01-01

BACKGROUND. T cells that have been modified to express a CD19-specific chimeric antigen receptor (CAR) have antitumor activity in B cell malignancies; however, identification of the factors that determine toxicity and efficacy of these T cells has been challenging in prior studies in which phenotypically heterogeneous CAR–T cell products were prepared from unselected T cells. METHODS. We conducted a clinical trial to evaluate CD19 CAR–T cells that were manufactured from defined CD4+ and CD8+ T cell subsets and administered in a defined CD4+:CD8+ composition to adults with B cell acute lymphoblastic leukemia after lymphodepletion chemotherapy. RESULTS. The defined composition product was remarkably potent, as 27 of 29 patients (93%) achieved BM remission, as determined by flow cytometry. We established that high CAR–T cell doses and tumor burden increase the risks of severe cytokine release syndrome and neurotoxicity. Moreover, we identified serum biomarkers that allow testing of early intervention strategies in patients at the highest risk of toxicity. Risk-stratified CAR–T cell dosing based on BM disease burden decreased toxicity. CD8+ T cell–mediated anti-CAR transgene product immune responses developed after CAR–T cell infusion in some patients, limited CAR–T cell persistence, and increased relapse risk. Addition of fludarabine to the lymphodepletion regimen improved CAR–T cell persistence and disease-free survival. CONCLUSION. Immunotherapy with a CAR–T cell product of defined composition enabled identification of factors that correlated with CAR–T cell expansion, persistence, and toxicity and facilitated design of lymphodepletion and CAR–T cell dosing strategies that mitigated toxicity and improved disease-free survival. TRIAL REGISTRATION. ClinicalTrials.gov NCT01865617. FUNDING. R01-CA136551; Life Science Development Fund; Juno Therapeutics; Bezos Family Foundation. PMID:27111235

Genome-wide expression profiling analysis to identify key genes in the anti-HIV mechanism of CD4+ and CD8+ T cells.

Science.gov (United States)

Gao, Lijie; Wang, Yunqi; Li, Yi; Dong, Ya; Yang, Aimin; Zhang, Jie; Li, Fengying; Zhang, Rongqiang

2018-07-01

Comprehensive bioinformatics analyses were performed to explore the key biomarkers in response to HIV infection of CD4 + and CD8 + T cells. The numbers of CD4 + and CD8 + T cells of HIV infected individuals were analyzed and the GEO database (GSE6740) was screened for differentially expressed genes (DEGs) in HIV infected CD4 + and CD8 + T cells. Gene Ontology enrichment, KEGG pathway analyses, and protein-protein interaction (PPI) network were performed to identify the key pathway and core proteins in anti-HIV virus process of CD4 + and CD8 + T cells. Finally, we analyzed the expressions of key proteins in HIV-infected T cells (GSE6740 dataset) and peripheral blood mononuclear cells(PBMCs) (GSE511 dataset). 1) CD4 + T cells counts and ratio of CD4 + /CD8 + T cells decreased while CD8 + T cells counts increased in HIV positive individuals; 2) 517 DEGs were found in HIV infected CD4 + and CD8 + T cells at acute and chronic stage with the criterial of P-value T cells. The main biological processes of the DEGs were response to virus and defense response to virus. At chronic stage, ISG15 protein, in conjunction with IFN-1 pathway might play key roles in anti-HIV responses of CD4 + T cells; and 4) The expression of ISG15 increased in both T cells and PBMCs after HIV infection. Gene expression profile of CD4 + and CD8 + T cells changed significantly in HIV infection, in which ISG15 gene may play a central role in activating the natural antiviral process of immune cells. © 2018 Wiley Periodicals, Inc.

CD8 Follicular T Cells Promote B Cell Antibody Class Switch in Autoimmune Disease.

Science.gov (United States)

Valentine, Kristen M; Davini, Dan; Lawrence, Travis J; Mullins, Genevieve N; Manansala, Miguel; Al-Kuhlani, Mufadhal; Pinney, James M; Davis, Jason K; Beaudin, Anna E; Sindi, Suzanne S; Gravano, David M; Hoyer, Katrina K

2018-05-09

CD8 T cells can play both a protective and pathogenic role in inflammation and autoimmune development. Recent studies have highlighted the ability of CD8 T cells to function as T follicular helper (Tfh) cells in the germinal center in the context of infection. However, whether this phenomenon occurs in autoimmunity and contributes to autoimmune pathogenesis is largely unexplored. In this study, we show that CD8 T cells acquire a CD4 Tfh profile in the absence of functional regulatory T cells in both the IL-2-deficient and scurfy mouse models. Depletion of CD8 T cells mitigates autoimmune pathogenesis in IL-2-deficient mice. CD8 T cells express the B cell follicle-localizing chemokine receptor CXCR5, a principal Tfh transcription factor Bcl6, and the Tfh effector cytokine IL-21. CD8 T cells localize to the B cell follicle, express B cell costimulatory proteins, and promote B cell differentiation and Ab isotype class switching. These data reveal a novel contribution of autoreactive CD8 T cells to autoimmune disease, in part, through CD4 follicular-like differentiation and functionality. Copyright © 2018 by The American Association of Immunologists, Inc.

Interleukin-9 receptor α chain mRNA formation in CD8+ T cells producing anti-human immunodeficiency virus type 1 substance(s)

International Nuclear Information System (INIS)

Hossain, M.M.; Tsuchie, H.; Detorio, M.A.; Shirono, H.; Hara, C.; Nishimoto, A.; Saji, A.; Koga, J.; Takata, N.; Maniar, J.K.; Saple, D.G.; Taniguchi, K.; Kageyama, S.; Ichimura, H.; Kurimura, T.

1998-01-01

A search for gene(s) associated with anti-human immunodeficiency virus type 1 (HIV-l) activity of CD8 + T cells was attempted using molecular cloning and the relation between the anti-HIV activity of CD8 + T cells and the interleukin-9 receptor a chain (IL-9R-α) mRNA expression from the cDNA clones obtained was examined. The anti-HIV-l activity of CD8 + T cell culture supernatants was assessed by measuring the level of HIV-l replication in a CD4 + T cell line transfected with an infectious HIV-l DNA clone. IL-9R-a mRNA was assayed by reverse transcriptase-polymerase chain reaction (RT-PCR). Of 5 cases showing high level of anti-HIV-l activity (more than 80% suppression of HIV-l replication), the mRNA was detected in 4 cases. Of 10 cases showing low level of anti-HIV-l activity (less than 80% suppression of HIV-l replication), the mRNA was detected in one case. Soluble recombinant human IL-9 receptor (rhIL-9sR) did not suppress HIV-l replication at a concentration of 1 μg/ml. These data suggest that the IL-9R-a mRNA formation in CD8 + T cells may correlate with and play some role in the anti-HIV-l activity of CD8+ T cells from HIV-l-infected individuals. Key words: CD8+ T cells; anti-HIV-l activity; cytokines; interleukin-9 receptor (authors)

Development of a lyophilized formulation for preparing the radiopharmaceutical {sup 177}Lu-DOTA-Anti-CD20; Desarrollo de una formulacion liofilizada para la preparacion del radiofarmaco {sup 177}-DOTA-Anti-CD20

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Serrano E, L. A.

2015-07-01

The radiolabeled proteins are molecules of interest in nuclear medicine for their diagnostic and therapeutic application in cancer. Antibodies, such as chimeric monoclonal antibody Anti-CD20 rituximab, have established themselves as suitable vectors of radionuclides (e.g. {sup 177}Lu) , introducing high affinity by the surface antigens over- expressed and widely distributed in cells involved in certain diseases. The aim of this work was to design, optimize and document the production process of radiopharmaceutical {sup 177}Lu-DOTA-Anti-CD20 for sanitary registration request to the Comision Federal para la Proteccion contra Riesgos Sanitarios (COFEPRIS). First, a raw material analysis using the Ft-Mir technique and gamma spectrometry was performed. Then, was carried out the development of the lyophilized formulation for the preparation of {sup 177}Lu-DOTA-Anti-CD20, in which an ANOVA was performed where the dependent variable was the radiochemical purity. The optimal pharmaceutical formulation was: 5 mg DOTA-CD20 and 80 mg Mannitol to be reconstituted with 1 m L of acetate buffer 0.25 M, ph 7, with an incubation time of 15 min at 37 degrees Celsius in a dry bath. Once completed the development of the lyophilized formulation, we proceeded to the optimization of the production process, development and validation of the analytical method. Three batches were prepared under protocols of Good Manufacturing Practice, which met pre-established specifications as sterile and endotoxin-free of bacterial formulations, with greater that 95% of radiochemical purity. Currently, is conducting the study of shelf stability. Upon completion of the stability studies, the legal record of {sup 177}Lu-DOTA-Anti-CD20 will be integrated with documented evidence of the quality and stability of the formulation of this radiopharmaceutical. (Author)

Recipient dendritic cells, but not B cells, are required antigen-presenting cells for peripheral alloreactive CD8+ T-cell tolerance.

Science.gov (United States)

Mollov, J L; Lucas, C L; Haspot, F; Gaspar, J Kurtz C; Guzman, A; Sykes, M

2010-03-01

Induction of mixed allogeneic chimerism is a promising approach for achieving donor-specific tolerance, thereby obviating the need for life-long immunosuppression for solid organ allograft acceptance. In mice receiving a low dose (3Gy) of total body irradiation, allogeneic bone marrow transplantation combined with anti-CD154 tolerizes peripheral CD4 and CD8 T cells, allowing achievement of mixed chimerism with specific tolerance to donor. With this approach, peripheral CD8 T-cell tolerance requires recipient MHC class II, CD4 T cells, B cells and DCs. Recipient-type B cells from chimeras that were tolerant to donor still promoted CD8 T-cell tolerance, but their role could not be replaced by donor-type B cells. Using recipients whose B cells or DCs specifically lack MHC class I and/or class II or lack CD80 and CD86, we demonstrate that dendritic cells (DCs) must express CD80/86 and either MHC class I or class II to promote CD8 tolerance. In contrast, B cells, though required, did not need to express MHC class I or class II or CD80/86 to promote CD8 tolerance. Moreover, recipient IDO and IL-10 were not required. Thus, antigen presentation by recipient DCs and not by B cells is critical for peripheral alloreactive CD8 T cell tolerance.

Regulatory effect of gamma-chain cytokines on expression of TIM-3 on CD8+ T cells in patients with chronic hepatitis B

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DONG Jie

2015-02-01

Full Text Available ObjectiveTo measure the expression of T-cell immunoglobulin- and mucin domain-3-containing molecule 3 (TIM-3 on CD8+ T cells in peripheral blood mononuclear cells (PBMCs among patients with chronic hepatitis B (CHB and to investigate the effect of common gamma-chain cytokines on the expression of TIM-3 on CD8+ T cells in these patients. MethodsFifteen previously untreated patients with CHB who visited the Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, from January to May, 2014, as well as 8 healthy controls, were included in the study. Blood was collected from these subjects, and PBMCs were isolated from blood by Ficoll density gradient centrifugation. PBMCs were separately stimulated with gamma-chain cytokines, interleukin (IL2, IL-7, IL-15, and IL-21, and anti-CD3/CD28, and the untreated cells were used as a negative control. After four days of culture, PBMCs were stained with monoclonal antibody. Flow cytometry was used to measure the expression of TIM-3 on CD8+ T cells. Comparison of continuous data was made by independent-samples t test. ResultsCompared with the untreated group, the anti-CD3/CD28, IL-2, IL-15, and IL-7 groups had significantly increased expression of TIM-3 on CD8+ T cells (9.629%±9.916%, P=0000 1; 3.817%±2.694%, P = 0.000 6; 5.772%±4.732%, P = 0.005 4; 3.560%±2.045%, P = 0.030 2, while the IL-21 group had nonsignificantly increased expression of TIM-3 on CD8+ T cells (2.503%±2.117%, P = 0.934 1. ConclusionAnti-CD3/CD28 and gamma-chain cytokines IL-2, IL-7, and IL-15 can effectively upregulate the expression of TIM-3 on CD8+ T cells in patients with CHB. It indicates that the inhibition of them can not only reduce the expression of TIM-3, but also may enhance the killing function of CD8+ T cells in patients with CHB.

In vitro characterization of 177Lu-radiolabelled chimeric anti-CD20 monoclonal antibody and a preliminary dosimetry study

International Nuclear Information System (INIS)

Forrer, Flavio; Mueller-Brand, Jan; Chen, Jianhua; Fani, Melpomeni; Powell, Pia; Maecke, Helmut R.; Lohri, Andreas; Moldenhauer, Gerhard

2009-01-01

131 I- and 90 Y-labelled anti-CD20 antibodies have been shown to be effective in the treatment of low-grade, B-cell non-Hodgkin's lymphoma (NHL). However, the most appropriate radionuclide in terms of high efficiency and low toxicity has not yet been established. In this study we evaluated an immunoconjugate formed by the anti-CD20 antibody rituximab and the chelator DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid). DOTA-rituximab was prepared as a kit formulation and can be labelled in a short time ( 177 Lu or 90 Y. Immunoconjugates with different numbers of DOTA molecules per rituximab were prepared using p-SCN-Bz-DOTA. In vitro immunoreactivity and stability were tested and preliminary dosimetric results were acquired in two patients. The immunological binding properties of DOTA-rituximab to the CD20 antigen were found to be retained after conjugation with up to four chelators. The labelled product was stable against a 10 5 times excess of diethylenetriaminepentaacetic acid (DTPA, 37 C, 7 days). Two patients with relapsed NHL were treated with 740 MBq/m 2 body surface 177 Lu-DOTA-rituximab. Scintigraphic images showed specific uptake at tumour sites and acceptable dosimetric results. The mean whole-body dose was found to be 314 mGy. The administration of 177 Lu-DOTA-rituximab was tolerated well. Our results show that DOTA-rituximab (4:1) can be labelled with 177 Lu with sufficient stability while the immunoconjugate retains its immunoreactivity. 177 Lu-DOTA-rituximab is an interesting, well-tolerated radiolabelled antibody with clinical activity in a low dose range, and provides an approach to the efficient treatment with few side effects for patients with relapsed NHL. (orig.)

In vitro characterization of {sup 177}Lu-radiolabelled chimeric anti-CD20 monoclonal antibody and a preliminary dosimetry study

Energy Technology Data Exchange (ETDEWEB)

Forrer, Flavio; Mueller-Brand, Jan [University Hospital Basel, Institute of Nuclear Medicine, Basel (Switzerland); Chen, Jianhua; Fani, Melpomeni; Powell, Pia; Maecke, Helmut R. [University Hospital Basel, Division of Radiological Chemistry, Basel (Switzerland); Lohri, Andreas [Basel University Medical Clinic, Liestal (Switzerland); Moldenhauer, Gerhard [German Cancer Research Center, Division of Molecular Immunology, Heidelberg (Germany)

2009-09-15

{sup 131}I- and {sup 90}Y-labelled anti-CD20 antibodies have been shown to be effective in the treatment of low-grade, B-cell non-Hodgkin's lymphoma (NHL). However, the most appropriate radionuclide in terms of high efficiency and low toxicity has not yet been established. In this study we evaluated an immunoconjugate formed by the anti-CD20 antibody rituximab and the chelator DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid). DOTA-rituximab was prepared as a kit formulation and can be labelled in a short time (<20 min) with either {sup 177}Lu or {sup 90}Y. Immunoconjugates with different numbers of DOTA molecules per rituximab were prepared using p-SCN-Bz-DOTA. In vitro immunoreactivity and stability were tested and preliminary dosimetric results were acquired in two patients. The immunological binding properties of DOTA-rituximab to the CD20 antigen were found to be retained after conjugation with up to four chelators. The labelled product was stable against a 10{sup 5} times excess of diethylenetriaminepentaacetic acid (DTPA, 37 C, 7 days). Two patients with relapsed NHL were treated with 740 MBq/m{sup 2} body surface {sup 177}Lu-DOTA-rituximab. Scintigraphic images showed specific uptake at tumour sites and acceptable dosimetric results. The mean whole-body dose was found to be 314 mGy. The administration of {sup 177}Lu-DOTA-rituximab was tolerated well. Our results show that DOTA-rituximab (4:1) can be labelled with {sup 177}Lu with sufficient stability while the immunoconjugate retains its immunoreactivity. {sup 177}Lu-DOTA-rituximab is an interesting, well-tolerated radiolabelled antibody with clinical activity in a low dose range, and provides an approach to the efficient treatment with few side effects for patients with relapsed NHL. (orig.)

Evaluation of dry blood spot technique for quantification of an Anti-CD20 monoclonal antibody drug in human blood samples.

Science.gov (United States)

Lin, Yong-Qing; Zhang, Yilu; Li, Connie; Li, Louis; Zhang, Kelley; Li, Shawn

2012-01-01

To evaluate the dried blood spot (DBS) technique in ELISA quantification of larger biomolecular drugs, an anti-CD20 monoclonal antibody drug was used as an example. A method for the quantification of the anti-CD20 drug in human DBS was developed and validated. The drug standard and quality control samples prepared in fresh human blood were spotted on DBS cards and then extracted. A luminescent ELISA was used for quantification of the drug from DBS samples. The assay range of the anti-CD20 drug standards in DBS was 100-2500ng/mL. The intra-assay precision (%CV) ranged from 0.4% to 10.1%, and the accuracy (%Recovery) ranged from 77.9% to 113.9%. The inter assay precision (%CV) ranged from 5.9% to 17.4%, and the accuracy ranged from 81.5% to 110.5%. The DBS samples diluted 500 and 50-fold yielded recovery of 88.7% and 90.7%, respectively. The preparation of DBS in higher and lower hematocrit (53% and 35%) conditions did not affect the recovery of the drug. Furthermore, the storage stability of the anti-CD20 drug on DBS cards was tested at various conditions. It was found that the anti-CD20 drug was stable for one week in DBS stored at room temperature. However, it was determined that the stability was compro]mised in DBS stored at high humidity, high temperature (55°C), and exposed to direct daylight for a week, as well as for samples stored at room temperature and high humidity conditions for a month. Stability did not change significantly in samples that underwent 3 freeze/thaw cycles. Our results demonstrated a successful use of DBS technique in ELISA quantification of an anti-CD20 monoclonal antibody drug in human blood. The stability data provides information regarding sample storage and shipping for future clinical studies. It is, therefore, concluded that the DBS technique is applicable in the quantification of other large biomolecule drugs or biomarkers. Copyright © 2011 Elsevier Inc. All rights reserved.

Children with acute lymphoblastic leukemia show high numbers of CD4+ and CD8+ T-cells which are reduced by conventional chemotherapy

OpenAIRE

Mohamed Labib Salem; Mohamed Ramadan El-Shanshory; Nabila Ibrahim El-Desouki; Said Hammad Abdou; Mohamed Attia Attia; Abdel-Aziz Awad Zidan; Shymaa Sobhy Mourad

2015-01-01

Background: Acute lymphoblastic leukemia (ALL) is considered as one of the most common cancer in pediatric malignancies. Among ALL, B-cell Acute Lymphoblastic Leukemia (B-ALL) represents 80% to 85% of the childhood ALL. Problem: Although anti B-ALL chemotherapy kill B-ALL, it associates with alteration in the numbers of CD4+ and CD8+ T-cells, and thus impacts the overall immunity. Aim: To evaluate the impact of anti B-ALL on the numbers of CD4+ and CD8+ T-cells in correlation to the n...

Imatinib treatment induces CD5+ B lymphocytes and IgM natural antibodies with anti-leukemic reactivity in patients with chronic myelogenous leukemia.

Directory of Open Access Journals (Sweden)

Silvia Catellani

Full Text Available Imatinib mesylate is a first line treatment of Chronic Myelogenous Leukemia and of a rare form of gastrointestinal stromal cancer, where the response to the drug is also linked to the immune system activation with production of antineoplastic cytokines. In this study, forty patients in the chronic phase of disease, treated with imatinib mesylate, were analyzed. Bone marrow aspirates were drawn at diagnosis, after 3, 6, 12, 18 months for haematological, cytofluorimetric, cytogenetic, biomolecular evaluation and cytokine measurement. Responder and non responder patients were defined according to the European LeukemiaNet recommendations. In responder patients (n = 32, the percentage of bone marrow CD20(+CD5(+sIgM(+ lymphocytes, and the plasma levels of IgM, were significantly higher, at 3 months and up to 9 months, than in non responders. These IgM reacted with O-linked sugars expressed by leukemic cells and could induce tumor cell apoptosis. In responder patients the stromal-derived factor-1 and the B-lymphocyte-activating factor of the tumor necrosis factor family significantly raised in the bone marrow after imatinib administration, together with the bone morphogenetic proteins-2 and -7. All patients with high number of CD20(+CD5(+sIgM(+ cells and high stromal-derived factor-1 and B lymphocyte activating factor levels, underwent complete cytogenetic and/or molecular remission by 12 months. We propose that CD20(+CD5(+sIgM(+ lymphocytes producing anti-carbohydrate antibodies with anti-tumor activity, might contribute to the response to imatinib treatment. As in multivariate analysis bone marrow CD20(+CD5(+sIgM(+ cells and stromal-derived factor-1 and B-lymphocyte-activating factor levels were significantly related to cytogenetical and molecular changes, they might contribute to the definition of the pharmacological response.

PU.1 is essential for CD11c expression in CD8(+/CD8(- lymphoid and monocyte-derived dendritic cells during GM-CSF or FLT3L-induced differentiation.

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Xue-Jun Zhu

Full Text Available Dendritic cells (DCs regulate innate and acquired immunity through their roles as antigen-presenting cells. Specific subsets of mature DCs, including monocyte-derived and lymphoid-derived DCs, can be distinguished based on distinct immunophenotypes and functional properties. The leukocyte integrin, CD11c, is considered a specific marker for DCs and it is expressed by all DC subsets. We created a strain of mice in which DCs and their progenitors could be lineage traced based on activity of the CD11c proximal promoter. Surprisingly, we observed levels of CD11c promoter activity that were similar in DCs and in other mature leukocytes, including monocytes, granulocytes, and lymphocytes. We sought to identify DNA elements and transcription factors that regulate DC-associated expression of CD11c. The ets transcription factor, PU.1, is a key regulator of DC development, and expression of PU.1 varies in different DC subsets. GM-CSF increased monocyte-derived DCs in mice and from mouse bone marrow cultured in vitro, but it did not increase CD8(+ lymphoid-derived DCs or B220(+ plasmacytoid DCs. FLT3L increased both monocyte-derived DCs and lymphoid-derived DCs from mouse bone marrow cultured in vitro. GM-CSF increased the 5.3 Kb CD11c proximal promoter activity in monocyte-derived DCs and CD8(+ lymphoid-derived DCs, but not in B220(+ plasmacytoid DCs. In contrast, FLT3L increased the CD11c proximal promoter activity in both monocyte-derived DCs and B220(+ plasmacytoid DCs. We used shRNA gene knockdown and chromatin immunoprecipitation to demonstrate that PU.1 is required for the effects of GM-CSF or FLT3L on monocyte-derived DCs. We conclude that both GM-CSF and FLT3L act through PU.1 to activate the 5.3 Kb CD11c proximal promoter in DCs and to induce differentiation of monocyte-derived DCs. We also confirm that the CD11c proximal promoter is not sufficient to direct lineage specificity of CD11c expression, and that additional DNA elements are required

CD4+ and CD8+ T cells can act separately in tumour rejection after immunization with murine pneumotropic virus chimeric Her2/neu virus-like particles.

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Kalle Andreasson

Full Text Available BACKGROUND: Immunization with murine pneumotropic virus virus-like particles carrying Her2/neu (Her2MPtVLPs prevents tumour outgrowth in mice when given prophylactically, and therapeutically if combined with the adjuvant CpG. We investigated which components of the immune system are involved in tumour rejection, and whether long-term immunological memory can be obtained. METHODOLOGY AND RESULTS: During the effector phase in BALB/c mice, only depletion of CD4+ and CD8+ in combination, with or without NK cells, completely abrogated tumour protection. Depletion of single CD4+, CD8+ or NK cell populations only had minor effects. During the immunization/induction phase, combined depletion of CD4+ and CD8+ cells abolished protection, while depletion of each individual subset had no or negligible effect. When tumour rejection was studied in knock-out mice with a C57Bl/6 background, protection was lost in CD4-/-CD8-/- and CD4-/-, but not in CD8-/- mice. In contrast, when normal C57Bl/6 mice were depleted of different cell types, protection was lost irrespective of whether only CD4+, only CD8+, or CD4+ and CD8+ cells in combination were eradicated. No anti-Her2/neu antibodies were detected but a Her2/neu-specific IFNgamma response was seen. Studies of long-term memory showed that BALB/c mice could be protected against tumour development when immunized together with CpG as long as ten weeks before challenge. CONCLUSION: Her2MPtVLP immunization is efficient in stimulating several compartments of the immune system, and induces an efficient immune response including long-term memory. In addition, when depleting mice of isolated cellular compartments, tumour protection is not as efficiently abolished as when depleting several immune compartments together.

Clinical Trials Using Anti-CD19/CD28/CD3zeta CAR Gammaretroviral Vector-transduced Autologous T Lymphocytes KTE-C19

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NCI supports clinical trials that test new and more effective ways to treat cancer. Find clinical trials studying anti-cd19/cd28/cd3zeta car gammaretroviral vector-transduced autologous t lymphocytes kte-c19.

Comparative studies of antibody anti-CD20 labeled with 188Re

International Nuclear Information System (INIS)

Dias, Carla Roberta de Barros Rodrigues

2010-01-01

Nuclear Medicine is an unique and important modality in oncology and the development of new tumor-targeted radiopharmaceuticals for both diagnosis and therapy is an area of interest for researchers. Rituximab (RTX) is a quimeric monoclonal antibody (mAb) (IgG 1) that specifically binds to CD20 antigen with high affinity and has been successfully used for the treatment of Non-Hodgkin Lymphoma (NHL) of cell B. The CD20 antigen is expressed over more than 90% of cell B NHL. Technetium-99m ( 99m Tc) and rhenium-188 ( 188 Re) are an attractive radionuclide pair for clinical use due to their favorable decay properties for diagnosis ( 99m Tc: T 1/2 = 6 h, γ radiation = 140 keV) and therapy ( 188 Re: T 1/2 = 17 h, maximum β energy = 2.12 MeV) and to their availability in the form of 99 Mo/ 99 mTc and 188 W/ 188 Re generators. The radionuclides can be conjugated to mAb using similar chemical procedures. The aim of this work was to study the labeling of anti-CD20 mAb (RTX) with 188 Re using two techniques: the direct labeling method [ 188 Re(V)] and the labeling method via the carbonyl nucleus [ 188 Re(I)]. Besides the quality control, the radiolabeled mAb was submitted to in vivo, in vitro and ex vivo biological studies. For the direct labeling, RTX was reducing by incubation with 2-mercaptoethanol for generating sulphydryl groups (-SH) and further labeled with 188 Re(V), in a study of several parameters in order to reach an optimized formulation. The labeling via the carbonyl nucleus both 99 mTc and 188 Re were employed through 2 different procedures: (1) labeling of intact RTX with 99 mTc(I) and (2) reduced RTX (RTX red ) labeled with 99 mTc(I)/ 188 Re(I). Also a parameter study was performed to obtain an optimized formulation. The quality control method for evaluating the radiochemical purity showed a good labeling yield (93%) for the direct method. The labeling method via carbonyl group, the results showed that the - SH groups of RTX red are a possible way of labeling

Increase in complement iC3b is associated with anti-inflammatory cytokine expression during late pregnancy in mice.

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Keigo Nakamura

Full Text Available Immunological tolerance between fetal allograft and mother is crucial for pregnancy establishment and maintenance; however, these mechanisms particularly those during the latter part of pregnancy have not been definitively elucidated. The aim of this study was to examine the presence and potential function of innate immunity characteristic to the middle to late pregnancy. We first characterized up-regulated proteins in decidua from day 11 pregnant (P11 mice using 2D-PAGE, followed by MALDI-TOF/MS analysis. These analyses identified increased complement component 3 (C3 and its derivatives in P11 decidua. We then found that in the decidual tissues, C3 mRNA increased on P15 and remained high on P19. C3 is converted to C3b and then iC3b by complement component factor I (Cfi and complement receptor 1-like protein (Crry, both of which were present in P19 placentas. In addition, iC3b proteins and its receptor CR3 (Cd11b/Cd18 in decidual and placental tissues increased toward the latter phase of pregnancy. Moreover, CR3 subunit CD11b protein was predominantly localized to spongiotrophoblast layer in the P19 placenta. Because iC3b is known to induce anti-inflammatory cytokine production, the analysis was extended to examine changes in pro- and anti-inflammatory cytokines, Il12, Il10, and Tgfb1. Il12 expression decreased in P15 and P19 placenta, while high mRNA expression of Il10 and Tgfb1 was found in P19 placental tissues. Furthermore, placental Il10 and Tgfb1 mRNAs were down-regulated when pregnant mice were treated with an anti-C3 antibody, detecting C3, C3b and iC3b. These results indicated that C3 derivatives, in particular, iC3b and its receptor CR3 were up-regulated at the fetal-maternal interface, and suggest that iC3b may regulate the placental expression of anti-inflammatory cytokines, IL10 and TGFB1, during the latter phase of pregnancy.

Multivalent system for therapy of non-Hod king lymphomas based on Anti-CD20 conjugated to gold nanoparticles

International Nuclear Information System (INIS)

Miranda O, R. M.

2014-01-01

In recent publications has been reported that gold nanoparticles have an effect in reducing the expression of the oncogene Bcl -2 and have a high biocompatibility , this is the importance for using gold nanoparticles for this work. The antibody CD20 is an antibody that specifically binds to that over expressed CD20 antigen on the cell membrane of B lymphoma cell non- Hodgkin (cell line Raji) behold the importance of combining this bio molecule to gold nanoparticles since they have a high specificity with CD20 positive cells , also to carry out the antigen- antibody immunological reactions triggered mediating cell lysis, possibly by cytotoxicity and apoptosis. Therefore, this system must have characteristics of both components to eliminate B cell non- Hodgkin lymphoma.In this work it was studied a multivalent system composed of gold nanoparticles and anti-CD20 antibody, the term multi valency refers to the number of biomolecules attached to the surface of the gold nanoparticle. The synthesis and characterization of the gold nanoparticles and the multivalent system was performed and the effect of the multivalent system on the expression of oncogene Bcl-2 (group of proteins associated with the apoptotic pathway) was evaluated. Characterization of raw materials and the multivalent system was performed using spectroscopic and microscopic techniques, this to verify structural changes in raw materials and thus confirm the formation of CD20 binding to the surface of the nanoparticle gold by the bond between gold and sulfur in the cysteines of CD20. Taking advantage that the metal nanoparticles have the optical property of surface plasmon resonance, the absorption of gold nanoparticles was measured on the UV-Vis as it is affected by the surface molecules bind to it, showing a bathochromic displacement effected. The hydrodynamic diameter of the gold nanoparticles was measured to verify that the antibody is bound to the surface; this evidence was complemented by micrographs

Natural CD8{sup +}25{sup +} regulatory T cell-secreted exosomes capable of suppressing cytotoxic T lymphocyte-mediated immunity against B16 melanoma

Energy Technology Data Exchange (ETDEWEB)

Xie, Yufeng; Zhang, Xueshu; Zhao, Tuo; Li, Wei; Xiang, Jim, E-mail: jim.xiang@saskcancer.ca

2013-08-16

Highlights: •CD8{sup +}25{sup +} regulatory T cells secrete tolerogenic exosomes. •CD8{sup +}25{sup +} regulatory T cell-derived exosomes exhibit immunosuppressive effect. •CD8{sup +}25{sup +} regulatory T cell-derived exosomes inhibit antitumor immunity. -- Abstract: Natural CD4{sup +}25{sup +} and CD8{sup +}25{sup +} regulatory T (Tr) cells have been shown to inhibit autoimmune diseases. Immune cells secrete exosomes (EXOs), which are crucial for immune regulation. However, immunomodulatory effect of natural Tr cell-secreted EXOs is unknown. In this study, we purified natural CD8{sup +}25{sup +} Tr cells from C57BL/6 mouse naive CD8{sup +} T cells, and in vitro amplified them with CD3/CD28 beads. EXOs (EXO{sub Tr}) were purified from Tr cell’s culture supernatants by differential ultracentrifugation and analyzed by electron microscopy, Western blot and flow cytometry. Our data showed that EXO{sub Tr} had a “saucer” or round shape with 50–100 nm in diameter, contained EXO-associated markers LAMP-1 and CD9, and expressed natural Tr cell markers CD25 and GITR. To assess immunomodulatory effect, we i.v. immunized C57BL/6 mice with ovalbumin (OVA)-pulsed DCs (DC{sub OVA}) plus Tr cells or EXO{sub Tr}, and then assessed OVA-specific CD8{sup +} T cell responses using PE-H-2K{sup b}/OVA tetramer and FITC-anti-CD8 antibody staining by flow cytometry and antitumor immunity in immunized mice with challenge of OVA-expressing BL6–10{sub OVA} melanoma cells. We demonstrated that DC{sub OVA}-stimulated CD8{sup +} T cell responses and protective antitumor immunity significantly dropped from 2.52% to 1.08% and 1.81% (p < 0.05), and from 8/8 to 2/8 and 5/8 mice DC{sub OVA} (p < 0.05) in immunized mice with co-injection of Tr cells and EXO{sub Tr}, respectively. Our results indicate that natural CD8{sup +}25{sup +} Tr cell-released EXOs, alike CD8{sup +}25{sup +} Tr cells, can inhibit CD8{sup +} T cell responses and antitumor immunity. Therefore, EXOs derived from

Anti-CD20 Radioimmunotherapy Before Chemotherapy and Stem Cell Transplant in Treating Patients With High-Risk B-Cell Malignancies

Science.gov (United States)

2018-03-13

Burkitt Lymphoma; CD20-Positive Neoplastic Cells Present; Diffuse Large B-Cell Lymphoma; Indolent Non-Hodgkin Lymphoma; Mantle Cell Lymphoma; Recurrent B-Cell Non-Hodgkin Lymphoma; Refractory Mature B-Cell Non-Hodgkin Lymphoma

Structure and physical properties of RT{sub 2}Cd{sub 20} (R=rare earth, T=Ni, Pd) compounds with the CeCr{sub 2}Al{sub 20}-type structure

Energy Technology Data Exchange (ETDEWEB)

Burnett, V.W.; Yazici, D.; White, B.D. [Department of Physics and Center for Advanced Nanoscience, University of California, San Diego, La Jolla, CA 92093 (United States); Dilley, N.R. [Quantum Design, 6325 Lusk Boulevard, San Diego, CA 92121 (United States); Friedman, A.J.; Brandom, B. [Department of Physics and Center for Advanced Nanoscience, University of California, San Diego, La Jolla, CA 92093 (United States); Maple, M.B., E-mail: mbmaple@physics.ucsd.edu [Department of Physics and Center for Advanced Nanoscience, University of California, San Diego, La Jolla, CA 92093 (United States)

2014-07-01

Eleven new compounds, R Ni{sub 2}Cd{sub 20} (R=Y, La–Nd, Sm, Gd, Tb) and R Pd{sub 2}Cd{sub 20} (R=Ce, Pr, Sm), were grown as single crystals in high temperature cadmium-rich solutions. They crystallize in the cubic CeCr{sub 2}Al{sub 20}-type structure (Fd3{sup ¯}m, Z=8) as characterized by measurements of powder X-ray diffraction. Electrical resistivity, magnetization, and specific heat measurements were performed on R Ni{sub 2}Cd{sub 20} (R=Y, La–Nd, Sm, Gd, Tb) single crystals. Whereas YNi{sub 2}Cd{sub 20} and LaNi{sub 2}Cd{sub 20} exhibit unremarkable metallic behavior, when magnetic moments from localized 4f electron states (Gd{sup 3+}–Tb{sup 3+}) are embedded into this host, they exhibit ferromagnetic order with values of the Curie temperature T{sub C} for R Ni{sub 2}Cd{sub 20} (R=Gd, and Tb) which scale with the de Gennes factor. - Graphical abstract: Specific heat divided by temperature C/T vs. T for single crystals of R Ni{sub 2}Cd{sub 20} (R=Y, La–Nd, Gd, and Tb). Left inset: Low temperature C/T vs. T{sup 2} for LaNi{sub 2}Cd{sub 20}. The solid line represents a linear fit of the data. Right inset: Low-temperature C/T data vs. T for R=Ce–Nd, Gd, and Tb; magnetic ordering temperatures are indicated by arrows. - Highlights: • R Ni{sub 2}Cd{sub 20} (R=Y, La–Nd, Sm, Gd, Tb) single crystals synthesized for the first time. • R Pd{sub 2}Cd{sub 20} (R=Ce, Pr, Sm) single crystals synthesized for the first time. • Single crystals are of good metallurgical quality (large RRR values). • NdNi{sub 2}Cd{sub 20} orders antiferromagnetically at T{sub N}=1.5 K. • R Ni{sub 2}Cd{sub 20} (R=Sm, Gd, Tb) order ferromagnetically.

Broad, Intense Anti-Human Immunodeficiency Virus (HIV) Ex Vivo CD8+ Responses in HIV Type 1-Infected Patients: Comparison with Anti-Epstein-Barr Virus Responses and Changes during Antiretroviral Therapy

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Dalod, Marc; Dupuis, Marion; Deschemin, Jean-Christophe; Sicard, Didier; Salmon, Dominique; Delfraissy, Jean-Francois; Venet, Alain; Sinet, Martine; Guillet, Jean-Gerard

1999-01-01

The ex vivo antiviral CD8+ repertoires of 34 human immunodeficiency virus (HIV)-seropositive patients with various CD4+ T-cell counts and virus loads were analyzed by gamma interferon enzyme-linked immunospot assay, using peptides derived from HIV type 1 and Epstein-Barr virus (EBV). Most patients recognized many HIV peptides, with markedly high frequencies, in association with all the HLA class I molecules tested. We found no correlation between the intensity of anti-HIV CD8+ responses and the CD4+ counts or virus load. In contrast, the polyclonality of anti-HIV CD8+ responses was positively correlated with the CD4+ counts. The anti-EBV responses were significantly less intense than the anti-HIV responses and were positively correlated with the CD4+ counts. Longitudinal follow-up of several patients revealed the remarkable stability of the anti-HIV and anti-EBV CD8+ responses in two patients with stable CD4+ counts, while both antiviral responses decreased in two patients with obvious progression toward disease. Last, highly active antiretroviral therapy induced marked decreases in the number of anti-HIV CD8+ T cells, while the anti-EBV responses increased. These findings emphasize the magnitude of the ex vivo HIV-specific CD8+ responses at all stages of HIV infection and suggest that the CD8+ hyperlymphocytosis commonly observed in HIV infection is driven mainly by virus replication, through intense, continuous activation of HIV-specific CD8+ T cells until ultimate progression toward disease. Nevertheless, highly polyclonal anti-HIV CD8+ responses may be associated with a better clinical status. Our data also suggest that a decrease of anti-EBV CD8+ responses may occur with depletion of CD4+ T cells, but this could be restored by highly active antiretroviral treatment. PMID:10438796

Increased Numbers of CD4+CD25+ and CD8+CD25+ T-Cells in Peripheral Blood of Patients with Rheumatoid Arthritis with Parvovirus B19 Infection.

Science.gov (United States)

Naciute, Milda; Maciunaite, Gabriele; Mieliauskaite, Diana; Rugiene, Rita; Zinkeviciene, Aukse; Mauricas, Mykolas; Murovska, Modra; Girkontaite, Irute

2017-01-01

To investigate T-cell subpopulations in peripheral blood of human parvovirus B19 DNA-positive (B19 + ) and -negative (B19 - ) patients with rheumatoid arthritis (RA) and healthy persons. Blood samples were collected from 115 patients with RA and 47 healthy volunteers; 27 patients with RA and nine controls were B19 + Cluster of differentiation (CD) 4, 8, 25 and 45RA were analyzed on blood cells. CD25 expression on CD4 + CD45RA + , CD4 + CD45RA - , CD8 + CD45RA + , CD8 + CD45RA - subsets were analyzed by flow cytometry. The percentage of CD25 low and CD25 hi cells was increased on CD4 + CD45RA + , CD4 + CD45RA - T-cells and the percentage of CD25 + cells was increased on CD8 + CD45RA + , CD8 + CD45RA - T-cells of B19 + patients with RA in comparison with B19 - patients and controls. Raised levels of CD4 and CD8 regulatory T-cells in B19 + RA patients could cause down-regulation of antiviral clearance mechanisms and lead to activation of persistent human parvovirus B19 infection in patients with RA. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Development of a lyophilized formulation for preparing the radiopharmaceutical 177Lu-DOTA-Anti-CD20

International Nuclear Information System (INIS)

Serrano E, L. A.

2015-01-01

The radiolabeled proteins are molecules of interest in nuclear medicine for their diagnostic and therapeutic application in cancer. Antibodies, such as chimeric monoclonal antibody Anti-CD20 rituximab, have established themselves as suitable vectors of radionuclides (e.g. 177 Lu) , introducing high affinity by the surface antigens over- expressed and widely distributed in cells involved in certain diseases. The aim of this work was to design, optimize and document the production process of radiopharmaceutical 177 Lu-DOTA-Anti-CD20 for sanitary registration request to the Comision Federal para la Proteccion contra Riesgos Sanitarios (COFEPRIS). First, a raw material analysis using the Ft-Mir technique and gamma spectrometry was performed. Then, was carried out the development of the lyophilized formulation for the preparation of 177 Lu-DOTA-Anti-CD20, in which an ANOVA was performed where the dependent variable was the radiochemical purity. The optimal pharmaceutical formulation was: 5 mg DOTA-CD20 and 80 mg Mannitol to be reconstituted with 1 m L of acetate buffer 0.25 M, ph 7, with an incubation time of 15 min at 37 degrees Celsius in a dry bath. Once completed the development of the lyophilized formulation, we proceeded to the optimization of the production process, development and validation of the analytical method. Three batches were prepared under protocols of Good Manufacturing Practice, which met pre-established specifications as sterile and endotoxin-free of bacterial formulations, with greater that 95% of radiochemical purity. Currently, is conducting the study of shelf stability. Upon completion of the stability studies, the legal record of 177 Lu-DOTA-Anti-CD20 will be integrated with documented evidence of the quality and stability of the formulation of this radiopharmaceutical. (Author)

Interferon-β-induced activation of c-Jun NH2-terminal kinase mediates apoptosis through up-regulation of CD95 in CH31 B lymphoma cells

International Nuclear Information System (INIS)

Takada, Eiko; Shimo, Kuniaki; Hata, Kikumi; Abiake, Maira; Mukai, Yasuo; Moriyama, Masami; Heasley, Lynn; Mizuguchi, Junichiro

2005-01-01

Type I interferon (IFN)-induced antitumor action is due in part to apoptosis, but the molecular mechanisms underlying IFN-induced apoptosis remain largely unresolved. In the present study, we demonstrate that IFN-β induced apoptosis and the loss of mitochondrial membrane potential (ΔΨm) in the murine CH31 B lymphoma cell line, and this was accompanied by the up-regulation of CD95, but not CD95-ligand (CD95-L), tumor necrosis factor (TNF), or TNF-related apoptosis-inducing ligand (TRAIL). Pretreatment with anti-CD95-L mAb partially prevented the IFN-β-induced loss of ΔΨm, suggesting that the interaction of IFN-β-up-regulated CD95 with CD95-L plays a crucial role in the induction of fratricide. IFN-β induced a sustained activation of c-Jun NH 2 -terminal kinase 1 (JNK1), but not extracellular signal-regulated kinases (ERKs). The IFN-β-induced apoptosis and loss of ΔΨm were substantially compromised in cells overexpressing a dominant-negative form of JNK1 (dnJNK1), and it was slightly enhanced in cells carrying a constitutively active JNK construct, MKK7-JNK1 fusion protein. The IFN-β-induced up-regulation of CD95 together with caspase-8 activation was also abrogated in the dnJNK1 cells while it was further enhanced in the MKK7-JNK1 cells. The levels of cellular FLIP (c-FLIP), competitively interacting with caspase-8, were down-regulated by stimulation with IFN-β but were reversed by the proteasome inhibitor lactacystin. Collectively, the IFN-β-induced sustained activation of JNK mediates apoptosis, at least in part, through up-regulation of CD95 protein in combination with down-regulation of c-FLIP protein

Evolving role of 2B4/CD244 in T and NK cell responses during virus infection

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Stephen Noel Waggoner

2012-12-01

Full Text Available The signaling lymphocyte activation molecule (SLAM family receptor, 2B4/CD244, was first implicated in anti-viral immunity by the discovery that mutations of the SLAM-associated protein, SAP/SH2D1A, impaired 2B4-dependent stimulation of T and natural killer (NK cell anti-viral functions in X-linked lymphoproliferative (XLP syndrome patients with uncontrolled Epstein-Barr virus (EBV infections. Engagement of 2B4 has been variably shown to either activate or inhibit lymphocytes which express this receptor. While SAP expression is required for stimulatory functions of 2B4 on lymphocytes, it remains unclear whether inhibitory signals derived from 2B4 can predominate even in the presence of SAP. Regardless, mounting evidence suggests that 2B4 expression by NK and CD8 T cells is altered by virus infection in mice as well as in humans, and 2B4-mediated signaling may be an important determinant of effective immune control of chronic virus infections. In this review, recent findings regarding the expression and function of 2B4 as well as SAP on T and NK cells during virus infection is discussed, with a focus on the role of 2B4-CD48 interactions in crosstalk between innate and adaptive immunity.

Effects of in vivo injection of anti-chicken CD25 monoclonal antibody on regulatory T cell depletion and CD4+CD25- T cell properties in chickens.

Science.gov (United States)

Shanmugasundaram, Revathi; Selvaraj, Ramesh K

2012-03-01

Regulatory T cells (Tregs) are defined as CD4(+)CD25(+) cells in chickens. This study examined the effects of an anti-chicken CD25 monoclonal antibody injection (0.5 mg/bird) on in vivo depletion of Tregs and the properties of CD4(+)CD25(-) cells in Treg-depleted birds. The CD4(+)CD25(+) cell percentage in the blood was lower at 8 d post injection than at 0 d. Anti-CD25-mediated CD4(+)CD25(+) cell depletion in blood was maximum at 12 d post injection. The anti-CD25 antibody injection depleted CD4(+)CD25(+) cells in the spleen and cecal tonsils, but not in the thymus, at 12 d post antibody injection. CD4(+)CD25(-) cells from the spleen and cecal tonsils of birds injected with the anti-chicken CD25 antibody had higher proliferation and higher IL-2 and IFNγ mRNA amounts than the controls at 12 d post injection. At 20 d post injection, CD4(+)CD25(+) cell percentages in the blood, spleen and thymus were comparable to that of the 0 d post injection. It could be concluded that anti-chicken CD25 injection temporarily depleted Treg population and increased and IL-2 and IFNγ mRNA amounts in CD4(+)CD25(-) cells at 12d post injection. Copyright © 2011 Elsevier Ltd. All rights reserved.

Follow-up of relapsed B-cell lymphoma patients treated with iodine-131-labeled anti-CD20 antibody and autologous stem-cell rescue

International Nuclear Information System (INIS)

Liu, S Y.; Eary, Janet F.; Petersdorf, S H.; Martin, P J.; Maloney, D G.; Applebaum, F. R.; Matthews, D. C.; Bush, S A.; Durack, L. D.; Fisher, Darrell R.; Gooley, T A.; Bernstein, I. D.; Press, O. W.

1997-01-01

Radioimmunotherapy (RIT) is a promising treatment approach for B-cell lymphomas. This is our first opportunity to report long-term follow-up data and late toxicities in 29 patients treated with myeloablative doses of iodine-131-anti-CD20 antibody (anti-B1) and autologous stem-cell rescue. PATIENTS AND METHODS: Trace-labeled biodistribution studies first determined the ability to deliver higher absorbed radiation doses to tumor sites than to lung, liver, or kidney at varying amounts of anti-B1 protein (0.35, 1.7, or 7 mg/kg). Twenty- nine patients received therapeutic infusions of single-agent (131)I- anti-B1, given at the protein dose found optimal in the biodistribution study, labeled with amounts of (131)I (280 to 785 mCi[10.4 to 29.0 GBq]) calculated to deliver specific absorbed radiation doses to the normal organs, followed by autologous stem-cell support. RESULTS: Major responses occurred in 25 patients (86%), with 23 complete responses (CRs; 79%). The nonhematopoietic do se-limiting toxicity was reversible cardiopulmonary insufficiency, which occurred in two patients at RIT doses that delivered > or = 27 Gy to the lungs. With a median follow-up time of 42 months, the estimated overall and progression-free survival rates are 68% and 42%, respectively. Currently, 14 of 29 patients remain in unmaintained remissions that range from 27+ to 87+ months after RIT. Late toxicities have been uncommon except for elevated thyroid-stimulating hormone (TSH) levels found in approximately 60% of the subjects. Two patients developed second malignancies, but none have developed myelodysplasia (MDS). CONCLUSION: Myeloablative (131)I-anti- B1 RIT is relatively well tolerated when given with autologous stem- cell support and often results in prolonged remission durations with few late toxicities

Evaluation of the cell death mechanisms activated by the radiopharmaceutical 177Lu-DOTA-anti-CD20 in a dose range of 1 to 5 Gy

International Nuclear Information System (INIS)

Azorin V, E.P.; Rojas C, E. L.; Martinez V, B. E.; Ramos B, J. C.; Jimenez M, N. P.; Ferro F, G.

2016-10-01

The radio immunotherapy with anti-CD20 antibodies significantly increases the remission rate of patients with B-cell lymphomas over expressing the CD20. The radiolabeled antibodies directed to surface antigens allow delivering scaled doses of radiation to specific targets thus limiting the dose to healthy tissue. The anti-CD20 causes cell death by two major pathways; activating the immune system to destroy malignant cells and inducing the activation of cell death pathways. The 177 Lu is a beta particle emitter (max. 0.497 MeV) with a maximum reach on soft tissue of 0.7 mm and a half-life of 6.7 days. Several clinical studies have established a maximum tolerated dose (45 m Ci/m 2 ) for 177 Lu-DOTA-rituximab, which shows a favorable clinical response without hematological toxicity. However, the molecular mechanisms of action by synergistic effect of anti-CD20 and radionuclide have not been studied. In this work was evaluated; by flow cytometry, the activation kinetics of the cell death mechanisms induced by the treatment with 177 Lu-DOTA-Anti-CD20 in non-Hodgkin (Raji) lymphoma cells. The absorbed radiation dose delivered to the cell nucleus was calculated by Monte Carlo simulation, considering the contribution of the beta emissions of the radiopharmaceutical present in the cell membrane and surrounding environment, as well as crossfire. This work shows that the application of radiation doses of 1 to 5 Gy of the radiopharmaceutical 177 Lu-DOTA-anti-CD20, are sufficient to induce cell death by apoptosis and arrest of the cell cycle. The combination of these factors (continuous delivery of radiation, activation of repair mechanisms and increased radio sensitivity) causes the acute activation of the apoptotic program resulting in significant cell death after 96 h of treatment. The temporal analysis of cell death suggests the early activation of apoptosis that is counteracted by the activation of repair processes caused by sustained irradiation, which leads to cell

The role of complement receptors type 1 (CR1, CD35) and 2 (CR2, CD21) in promoting C3 fragment deposition and membrane attack complex formation on normal peripheral human B cells

DEFF Research Database (Denmark)

Nielsen, Claus Henrik; Pedersen, Morten Løbner; Marquart, Hanne Vibeke Hansen

2002-01-01

Normal human B lymphocytes are known to activate the alternative pathway (AP) of complement, leading to C3-fragment deposition and membrane attack complex (MAC) formation. The process is mediated via complement receptor type 2 (CR2, CD21), with complement receptor type 1 (CR1, CD35) playing...... a subsidiary role. In this study, we examine the relative contributions of CR1 and CR2 to the deposition of C3 fragments and MAC on B lymphocytes under circumstances where all complement pathways are operational. C3-fragment deposition and MAC formation were assessed on human peripheral B lymphocytes...... in the presence of 30% autologous serum. Blocking the CR2 ligand-binding site with monoclonal antibody (mAb) FE8 resulted in significant reduction (37.9+/-11.9%) in C3-fragment deposition, whereas MAC formation was only marginally affected (12.1+/-22.2% reduction). Blocking the CR1 binding-site resulted...

Observation of Ξc(2930)0 and updated measurement of B- → K-Λc+ anti Λc- at Belle

International Nuclear Information System (INIS)

Li, Y.B.; Ban, Y.; Shen, C.P.; Jia, S.; Adachi, I.; Haba, J.; Hara, T.; Itoh, R.; Nakao, M.; Nishida, S.; Sakai, Y.; Uno, S.; Ahn, J.K.; Kim, J.B.; Kim, K.T.; Moon, H.K.; Won, E.; Aihara, H.; Jin, Y.; Al Said, S.; Asner, D.M.; Bansal, V.; Cunliffe, S.; Fast, J.E.; Fulsom, B.G.; Strube, J.F.; Aushev, T.; Popov, V.; Ayad, R.; Babu, V.; Mohanty, G.B.; Badhrees, I.; Bakich, A.M.; Behera, P.; Libby, J.; Berger, M.; Widmann, E.; Bhardwaj, V.; Bhuyan, B.; Nath, K.J.; Biswal, J.; Lubej, M.; Mrvar, M.; Nanut, T.; Pestotnik, R.; Staric, M.; Bonvicini, G.; Cinabro, D.; Di Carlo, S.; Bozek, A.; Natkaniec, Z.; Bracko, M.; Korpar, S.; Browder, T.E.; Hedges, M.T.; Kotchetkov, D.; Varner, G.; Cervenkov, D.; Dolezal, Z.; Drasal, Z.; Kodys, P.; Chekelian, V.; Kiesling, C.; Li Gioi, L.; Chen, A.; Cheon, B.G.; Kim, S.H.; Lee, I.S.; Unno, Y.; Chilikin, K.; Pakhlov, P.; Zhukova, V.; Cho, K.; Choi, S.K.; Choi, Y.; Park, C.W.; Dash, N.; Eidelman, S.; Epifanov, D.; Gabyshev, N.; Garmash, A.; Krokovny, P.; Kuzmin, A.; Shebalin, V.; Shwartz, B.; Vorobyev, V.; Zhilich, V.; Zhulanov, V.; Ferber, T.; Inguglia, G.; Karyan, G.; Rostomyan, A.; Ye, H.; Garg, R.; Gaur, V.; Piilonen, L.E.; Gelb, M.; Goldenzweig, P.; Giri, A.; Guido, E.; Mussa, R.; Hayasaka, K.; Kawasaki, T.; Miyata, H.; Seino, Y.; Watanabe, M.; Yusa, Y.; Hayashii, H.; Miyabayashi, K.; Hou, W.S.; Shiu, J.G.; Wang, M.Z.; Iijima, T.; Inami, K.; Kato, Y.; Mori, T.; Ishikawa, A.; Sanuki, T.; Iwasaki, M.; Nakano, E.; Iwasaki, Y.; Kichimi, H.; MacNaughton, J.; Santelj, L.; Jacobs, W.W.; Vossen, A.; Joo, K.K.; Julius, T.; Tenchini, F.; Waheed, E.; Kim, D.Y.; Kinoshita, K.; Pal, B.; Sandilya, S.; Wang, B.; Krizan, P.; Kroeger, R.; Kulasiri, R.; Kumita, T.; Sumiyoshi, T.; Kwon, Y.J.; Lee, S.C.; Park, H.; Li, L.K.; Wang, P.; Yuan, C.Z.; Liventsev, D.; Luo, T.; Wang, X.L.; Masuda, M.; Matsuda, T.; Merola, M.; Pardi, S.; Russo, G.; Mizuk, R.; Nayak, M.; Niiyama, M.; Ogawa, S.; Pakhlova, G.; Solovieva, E.; Uglov, T.; Zakharov, S.; Paul, S.; Pedlar, T.K.; Salehi, M.; Schneider, O.; Schnell, G.; Schwanda, C.; Shibata, T.A.; Uchida, M.; Sokolov, A.; Sumihama, M.; Takizawa, M.; Tamponi, U.; Tanida, K.; Hulse, C. van; Wang, C.H.; Watanabe, Y.; Yelton, J.; Zhang, Z.P.

2018-01-01

We report the first observation of the Ξ c (2930) 0 charmed-strange baryon with a significance greater than 5σ. The Ξ c (2930) 0 is found in its decay to K - Λ c + in decays. The measured mass and width are [2928.9 ± 3.0(stat.) +0.9 -12.0 (syst.)] MeV/c 2 and [19.5 ± 8.4(stat.) +5.9 -7.9 (syst.)] MeV, respectively, and the product branching fraction is B(B - → Ξ c (2930) 0 anti Λ c - ) B(Ξ c (2930) 0 → K - Λ c + ) = [1.73 ± 0.45(stat.) ± 0.21(syst.)] x 10 -4 . We also measure B(B - → K - Λ c + anti Λ c - ) = [4.80 ± 0.43(stat.) ± 0.60(syst.)] x 10 -4 with improved precision, and search for the charmonium-like state Y(4660) and its spin partner, Y η , in the Λ c + anti Λ c - invariant mass spectrum. No clear signals of the Y(4660) nor its spin partner are observed and the 90% credibility level (C.L.) upper limits on their production rates are determined. These measurements are obtained from a sample of (772� ± 11) � x 10 6 B anti B pairs collected at the Υ(4S) resonance by the Belle detector at the KEKB asymmetric energy electron.positron collider. (orig.)

G-CSF/anti-G-CSF antibody complexes drive the potent recovery and expansion of CD11b+Gr-1+ myeloid cells without compromising CD8+ T cell immune responses

Science.gov (United States)

2013-01-01

Background Administration of recombinant G-CSF following cytoreductive therapy enhances the recovery of myeloid cells, minimizing the risk of opportunistic infection. Free G-CSF, however, is expensive, exhibits a short half-life, and has poor biological activity in vivo. Methods We evaluated whether the biological activity of G-CSF could be improved by pre-association with anti-G-CSF mAb prior to injection into mice. Results We find that the efficacy of G-CSF therapy can be enhanced more than 100-fold by pre-association of G-CSF with an anti-G-CSF monoclonal antibody (mAb). Compared with G-CSF alone, administration of G-CSF/anti-G-CSF mAb complexes induced the potent expansion of CD11b+Gr-1+ myeloid cells in mice with or without concomitant cytoreductive treatment including radiation or chemotherapy. Despite driving the dramatic expansion of myeloid cells, in vivo antigen-specific CD8+ T cell immune responses were not compromised. Furthermore, injection of G-CSF/anti-G-CSF mAb complexes heightened protective immunity to bacterial infection. As a measure of clinical value, we also found that antibody complexes improved G-CSF biological activity much more significantly than pegylation. Conclusions Our findings provide the first evidence that antibody cytokine complexes can effectively expand myeloid cells, and furthermore, that G-CSF/anti-G-CSF mAb complexes may provide an improved method for the administration of recombinant G-CSF. PMID:24279871

Co-stimulation by anti-immunoglobulin is required for B cell activation by CD40Llow T cells

DEFF Research Database (Denmark)

Poudrier, J; Owens, T

1994-01-01

cell Ag specificity by using anti-CD3/T cell receptor (TcR) monoclonal antibodies (mAb) to activate T cells. To study the role of sIg engagement in the responsiveness of B cells to T help, we pre-treated small resting B cells with soluble anti-kappa mAb prior to contact with an activated Th1 clone...... strongly. Low buoyant density B cells also responded to CD40Llow Th cells. There was no B cell response to resting Th cells. mAb against CD54/intercellular adhesion molecule-1 or major histocompatibility complex (MHC) class II completely inhibited B cell responses to CD40Llow Th1 cells, equivalent...

Search for ZX → ν anti ν b anti b Events in the D-Zero Detector

International Nuclear Information System (INIS)

Abbott, B.

1997-10-01

We report on a search for a new particle, X, decaying via X → b anti b, made through associated production with a Z boson. We use data collected with the D0 detector operating at the Fermilab Tevatron p anti p collider with √s = 1.8 TeV. We utilize muon-tagged jets to identify b-quarks and the ν anti ν channel to detect Z bosons. Preliminary results on cross section limits for X masses between 90 GeV/c 2 and 180 GeV/c 2 are presented

Evaluation of cell death mechanisms activated by the administration of the theranostics radiopharmaceutical {sup 177}Lu-DOTA-anti-CD20 in a dose range of 1-5 Gy; Evaluacion de los mecanismos de muerte celular activados por la administracion del radiofarmaco teranostico {sup 177}Lu-DOTA-anti-CD20 en un rango de dosis de 1-5 Gy

Energy Technology Data Exchange (ETDEWEB)

Martinez V, B. E.

2016-07-01

Radio-immunotherapy with anti-CD20 antibodies significantly increases the rate of remission in patients with CD20 over expressing B-cell lymphomas. Radio-labeled antibodies directed to surface antigens allow delivering scaled doses of radiation to specific targets thus limiting the dose to healthy tissue. Anti-CD20 causes cell death by two major pathways; activating the immune system to destroy malignant cells and inducing the activation of cell death pathways. The {sup 177}Lu is a beta particle emitter (max. 0.497 MeV) with a maximum soft tissue reach of 0.7 mm and a half-life of 6.7 days. Several clinical studies have established a maximum tolerated dose (45m Ci/m{sup 2}) for {sup 177}Lu-DOTA-rituximab, which shows a favorable clinical response without hematological toxicity. However, the molecular mechanisms of synergistic activation of anti-CD20 and radionuclide have not been studied. In this work we evaluated by flow cytometry, the activation kinetics of the cell death mechanisms induced by the treatment with {sup 177}Lu-DOTA-anti-CD20 from non-Hod king lymphoma cells (Raji). The absorbed radiation dose delivered to the cell nucleus was calculated by Monte Carlo simulation, considering the contribution of the beta emissions of the radiopharmaceutical present in the cell membrane and surrounding environment, as well as crossfire. This work shows that the application of radiation doses of 1 to 5 Gy of the radiopharmaceutical {sup 177}Lu-DOTA-anti-CD20 are sufficient to induce cell death by apoptosis and arrest of the cell cycle. The combination of these factors (continuous delivery of radiation activation of repair mechanisms and increased radio-sensitivity) causes acute activation of the apoptotic program resulting in significant cell death after 96 h of treatment. The temporal analysis of cell death suggests the early activation of apoptosis that is counteracted by the activation of repair processes caused by sustained irradiation, which leads to cell arrest

Retinoic acid induction of CD1d expression primes chronic lymphocytic leukemia B cells for killing by CD8+ invariant natural killer T cells.

Science.gov (United States)

Ghnewa, Yasmeen G; O'Reilly, Vincent P; Vandenberghe, Elisabeth; Browne, Paul V; McElligott, Anthony M; Doherty, Derek G

2017-10-01

Invariant natural killer T (iNKT) cells are cytotoxic T cells that respond to glycolipid antigens presented by CD1d. Therapeutic activation of iNKT cells with α-galactosylceramide (α-GalCer) can prevent and reverse tumor growth in mice and clinical trials involving α-GalCer-stimulated iNKT cells are ongoing in humans. B cells express CD1d, however, we show that CD1d expression is reduced on B cells from patients with chronic lymphocytic leukemia (CLL). B cells from CLL patients pulsed with α-GalCer failed to stimulate cytolytic degranulation by iNKT cell lines, but could present the more potent glycolipid analogue, 7DW8-5. Retinoic acid receptor-α (RAR-α) agonists induced CD1d expression by CLL B cells, restoring their ability to present α-GalCer to CD8α + iNKT cells, resulting in cytolytic degranulation. Thus, RAR-α agonists can augment the anti-tumor activities of iNKT cells against CLL cells in vitro. Their inclusion in iNKT cell-based therapies may benefit patients with CLL. Copyright © 2017 Elsevier Inc. All rights reserved.

Identification of relevant drugable targets in diffuse large B-cell lymphoma using a genome-wide unbiased CD20 guilt-by association approach

NARCIS (Netherlands)

de Jong, Mathilde R. W.; Visser, Lydia; Huls, Gerwin; Diepstra, Arjan; van Vugt, Marcel; Ammatuna, Emanuele; van Rijn, Rozemarijn S.; Vellenga, Edo; van den Berg, Anke; Fehrmann, Rudolf S. N.; van Meerten, Tom

2018-01-01

Forty percent of patients with diffuse large B-cell lymphoma (DLBCL) show resistant disease to standard chemotherapy (CHOP) in combination with the anti-CD20 monoclonal antibody rituximab (R). Although many new anti-cancer drugs were developed in the last years, it is unclear which of these drugs

Scale dependence of open c anti c and b anti b production in the low x region

Energy Technology Data Exchange (ETDEWEB)

Oliveira, E.G. de [Universidade Federal de Santa Catarina, Departamento de Fisica, CFM, C.P. 476, Florianopolis, SC (Brazil); University of Durham, Institute for Particle Physics Phenomenology, Durham (United Kingdom); Martin, A.D. [University of Durham, Institute for Particle Physics Phenomenology, Durham (United Kingdom); Ryskin, M.G. [University of Durham, Institute for Particle Physics Phenomenology, Durham (United Kingdom); NRC Kurchatov Institute, Petersburg Nuclear Physics Institute, St. Petersburg (Russian Federation)

2017-03-15

The 'optimal' factorization scale μ{sub 0} is calculated for open heavy quark production. We find that the optimal value is μ{sub F} = μ{sub 0} ≅ 0.85√(p{sup 2}{sub T}+m{sub Q}{sup 2}); a choice which allows us to resum the double-logarithmic, (α{sub s} ln μ{sup 2}{sub F} ln (1/x)){sup n} corrections (enhanced at LHC energies by large values of ln(1/x)) and to move them into the incoming parton distributions, PDF (x, μ{sub 0}{sup 2}). Besides this result for the single inclusive cross section (corresponding to an observed heavy quark of transverse momentum p{sub T}), we also determined the scale for processes where the acoplanarity can be measured; that is, events where the azimuthal angle between the quark and the antiquark may be determined experimentally. Moreover, we discuss the important role played by the 2 → 2 subprocesses, gg → Q anti Q at NLO and higher orders. In summary, we achieve a better stability of the QCD calculations, so that the data on c anti c and b anti b production can be used to further constrain the gluons in the small x, relatively low scale, domain, where the uncertainties of the global analyses are large at present. (orig.)

A viral long terminal repeat expressed in CD4+CD8+ precursors is downregulated in mature peripheral CD4-CD8+ or CD4+CD8- T cells.

OpenAIRE

Paquette, Y; Doyon, L; Laperrière, A; Hanna, Z; Ball, J; Sekaly, R P; Jolicoeur, P

1992-01-01

The long terminal repeat from a thymotropic mouse mammary tumor virus variant, DMBA-LV, was used to drive the expression of two reporter genes, murine c-myc and human CD4, in transgenic mice. Expression was observed specifically in thymic immature cells. Expression of c-myc in these cells induced oligoclonal CD4+ CD8+ T-cell thymomas. Expression of human CD4 was restricted to thymic progenitor CD4- CD8- and CD4+ CD8+ T cells and was shut off in mature CD4+ CD8- and CD4- CD8+ T cells, known to...

Aging Converts Innate B1a Cells into Potent CD8+ T Cell Inducers.

Science.gov (United States)

Lee-Chang, Catalina; Bodogai, Monica; Moritoh, Kanako; Chen, Xin; Wersto, Robert; Sen, Ranjan; Young, Howard A; Croft, Michael; Ferrucci, Luigi; Biragyn, Arya

2016-04-15

B cell dysregulation in aging is thought to mostly occur in conventional B2 cells without affecting innate B1 cells. Elderly humans and mice also accumulate 4-1BBL(+)MHC class-I(Hi)CD86(Hi)B cells of unknown origin. In this article, we report that these cells, termed 4BL cells, are activated murine and possibly human B1a cells. The activation is mediated by aging human monocytes and murine peritoneal macrophages. They induce expression and activation of 4-1BBL and IFN-γR1 on B1a cells to subsequently upregulate membrane TNF-α and CD86. As a result, activated B1a/4BL cells induce expression of granzyme B in CD8(+)T cells by targeting TNFR2 via membrane TNF-α and providing costimulation with CD86. Thus, for the first time, to our knowledge, these results indicate that aging affects the function of B1a cells. Upon aging, these cells lose their tumor-supporting activity and become inducers of potentially antitumor and autoimmune CD8(+)T cells. Copyright © 2016 by The American Association of Immunologists, Inc.

Evaluation of the cell death mechanisms activated by the radiopharmaceutical {sup 177}Lu-DOTA-anti-CD20 in a dose range of 1 to 5 Gy; Evaluacion de los mecanismos de muerte celular activados por el radiofarmaco {sup 177}Lu-DOTA-anti-CD20 en un intervalo de dosis de 1 a 5 Gy

Energy Technology Data Exchange (ETDEWEB)

Azorin V, E.P.; Rojas C, E. L.; Martinez V, B. E.; Ramos B, J. C.; Jimenez M, N. P.; Ferro F, G., E-mail: erica.azorin@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

2016-10-15

The radio immunotherapy with anti-CD20 antibodies significantly increases the remission rate of patients with B-cell lymphomas over expressing the CD20. The radiolabeled antibodies directed to surface antigens allow delivering scaled doses of radiation to specific targets thus limiting the dose to healthy tissue. The anti-CD20 causes cell death by two major pathways; activating the immune system to destroy malignant cells and inducing the activation of cell death pathways. The {sup 177}Lu is a beta particle emitter (max. 0.497 MeV) with a maximum reach on soft tissue of 0.7 mm and a half-life of 6.7 days. Several clinical studies have established a maximum tolerated dose (45 m Ci/m{sup 2}) for {sup 177}Lu-DOTA-rituximab, which shows a favorable clinical response without hematological toxicity. However, the molecular mechanisms of action by synergistic effect of anti-CD20 and radionuclide have not been studied. In this work was evaluated; by flow cytometry, the activation kinetics of the cell death mechanisms induced by the treatment with {sup 177}Lu-DOTA-Anti-CD20 in non-Hodgkin (Raji) lymphoma cells. The absorbed radiation dose delivered to the cell nucleus was calculated by Monte Carlo simulation, considering the contribution of the beta emissions of the radiopharmaceutical present in the cell membrane and surrounding environment, as well as crossfire. This work shows that the application of radiation doses of 1 to 5 Gy of the radiopharmaceutical {sup 177}Lu-DOTA-anti-CD20, are sufficient to induce cell death by apoptosis and arrest of the cell cycle. The combination of these factors (continuous delivery of radiation, activation of repair mechanisms and increased radio sensitivity) causes the acute activation of the apoptotic program resulting in significant cell death after 96 h of treatment. The temporal analysis of cell death suggests the early activation of apoptosis that is counteracted by the activation of repair processes caused by sustained irradiation

The equiatomic intermetallics REPtCd (RE = La, Ce, Pr, Nd, Eu) and magnetic properties of CeAuCd

Energy Technology Data Exchange (ETDEWEB)

Johnscher, Michael; Niehaus, Oliver; Poettgen, Rainer [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Tappe, Frank [Hochschule Hamm-Lippstadt, Hamm (Germany)

2015-06-01

The cadmium intermetallics REPtCd (RE = La, Ce, Pr, Nd, Eu) and CeAuCd were synthesized by induction-melting of the elements in sealed niobium ampoules followed by annealing in muffle furnaces. The samples were characterized by powder X-ray diffraction. The structures of CePtCd (ZrNiAl type, P anti 62m, a = 763.8(6), c = 409.1(4) pm, wR2 = 0.0195, 298 F{sup 2} values, 14 variables) and EuPtCd (TiNiSi type, Pnma, a = 741.3(2), b = 436.4(1), c = 858.0(4) pm, wR2 = 0.0385, 440 F{sup 2} values, 20 variables) were refined from single-crystal data. The REPtCd structures exhibit three-dimensional networks of corner- and edge-sharing Cd rate at Pt{sub 2/6}Pt{sub 2/3} and Cd rate at Pt{sub 4/4} tetrahedra, which leave cages for the rare earth atoms. Temperature-dependent magnetic susceptibility data of CeAuCd reveal a paramagnetic to antiferromagnetic phase transition at T{sub N} = 3.7(5) K.

The equiatomic intermetallics REPtCd (RE = La, Ce, Pr, Nd, Eu) and magnetic properties of CeAuCd

International Nuclear Information System (INIS)

Johnscher, Michael; Niehaus, Oliver; Poettgen, Rainer

2015-01-01

The cadmium intermetallics REPtCd (RE = La, Ce, Pr, Nd, Eu) and CeAuCd were synthesized by induction-melting of the elements in sealed niobium ampoules followed by annealing in muffle furnaces. The samples were characterized by powder X-ray diffraction. The structures of CePtCd (ZrNiAl type, P anti 62m, a = 763.8(6), c = 409.1(4) pm, wR2 = 0.0195, 298 F 2 values, 14 variables) and EuPtCd (TiNiSi type, Pnma, a = 741.3(2), b = 436.4(1), c = 858.0(4) pm, wR2 = 0.0385, 440 F 2 values, 20 variables) were refined from single-crystal data. The REPtCd structures exhibit three-dimensional networks of corner- and edge-sharing Cd rate at Pt 2/6 Pt 2/3 and Cd rate at Pt 4/4 tetrahedra, which leave cages for the rare earth atoms. Temperature-dependent magnetic susceptibility data of CeAuCd reveal a paramagnetic to antiferromagnetic phase transition at T N = 3.7(5) K.

The Role of Heterotypic DENV-specific CD8+T Lymphocytes in an Immunocompetent Mouse Model of Secondary Dengue Virus Infection.

Science.gov (United States)

Talarico, Laura B; Batalle, Juan P; Byrne, Alana B; Brahamian, Jorge M; Ferretti, Adrián; García, Ayelén G; Mauri, Aldana; Simonetto, Carla; Hijano, Diego R; Lawrence, Andrea; Acosta, Patricio L; Caballero, Mauricio T; Paredes Rojas, Yésica; Ibañez, Lorena I; Melendi, Guillermina A; Rey, Félix A; Damonte, Elsa B; Harris, Eva; Polack, Fernando P

2017-06-01

Dengue is the most prevalent arthropod-borne viral disease worldwide and is caused by the four dengue virus serotypes (DENV-1-4). Sequential heterologous DENV infections can be associated with severe disease manifestations. Here, we present an immunocompetent mouse model of secondary DENV infection using non mouse-adapted DENV strains to investigate the pathogenesis of severe dengue disease. C57BL/6 mice infected sequentially with DENV-1 (strain Puerto Rico/94) and DENV-2 (strain Tonga/74) developed low platelet counts, internal hemorrhages, and increase of liver enzymes. Cross-reactive CD8 + T lymphocytes were found to be necessary and sufficient for signs of severe disease by adoptively transferring of DENV-1-immune CD8 + T lymphocytes before DENV-2 challenge. Disease signs were associated with production of tumor necrosis factor (TNF)-α and elevated cytotoxicity displayed by heterotypic anti-DENV-1 CD8 + T lymphocytes. These findings highlight the critical role of heterotypic anti-DENV CD8 + T lymphocytes in manifestations of severe dengue disease. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

CD47 limits antibody dependent phagocytosis against non-malignant B cells.

Science.gov (United States)

Gallagher, Sandra; Turman, Sean; Lekstrom, Kristen; Wilson, Susan; Herbst, Ronald; Wang, Yue

2017-05-01

Recent studies have demonstrated the importance of CD47 in protecting malignant B cells from antibody dependent cellular phagocytosis (ADCP). Combined treatment of anti-CD47 and -CD20 antibodies synergistically augment elimination of tumor B cells in xenograft mouse models. This has led to the development of novel reagents that can potentially enhance killing of malignant B cells in patients. B cell depleting therapy is also a promising treatment for autoimmune patients. In the current study, we aimed to investigate whether or not CD47 protects non-malignant B cells from ADCP. We show that CD47 is expressed on all B cells in mice, with the highest level on plasma cells in bone marrow and spleen. Although its expression is dispensable for B cell development in mice, CD47 on B cells limits antibody mediated phagocytosis. B cell depletion following in vivo anti-CD19 treatment is more efficient in CD47-/- mice than in wild type mice. In vitro, both naïve and activated B cells from CD47-/- mice are more sensitive to ADCP than wild type B cells. Lastly, we show in an ADCP assay that blocking CD47 can enhance anti-CD19 antibody mediated phagocytosis of wild type B cells. These results suggest that in addition to its already demonstrated benefit in cancer, targeting CD47 may be used as an adjunct in combination with B cell depletion antibodies for treatment of autoimmune diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

Immuno-biosensor for Detection of CD20-Positive Cells Using Surface Plasmon Resonance

Science.gov (United States)

Shanehbandi, Dariush; Majidi, Jafar; Kazemi, Tohid; Baradaran, Behzad; Aghebati-Maleki, Leili; Fathi, Farzaneh; Ezzati Nazhad Dolatabadi, Jafar

2017-01-01

Purpose: Surface plasmon resonance (SPR) sensing confers a real-time assessment of molecular interactions between biomolecules and their ligands. This approach is highly sensitive and reproducible and could be employed to confirm the successful binding of drugs to cell surface targets. The specific affinity of monoclonal antibodies (MAb) for their target antigens is being utilized for development of immuno-sensors and therapeutic agents. CD20 is a surface protein of B lymphocytes which has been widely employed for immuno-targeting of B-cell related disorders. In the present study, binding ability of an anti-CD20 MAb to surface antigens of intact target cells was investigated by SPR technique. Methods: Two distinct strategies were used for immobilization of the anti-CD20 MAb onto gold (Au) chips. MUA (11-mercaptoundecanoic acid) and Staphylococcus aureus protein A (SpA) were the two systems used for this purpose. A suspension of CD20-positive Raji cells was injected in the analyte phase and the resulting interactions were analyzed and compared to those of MOLT-4 cell line as CD20-negative control. Results: Efficient binding of anti-CD20 MAb to the surface antigens of Raji cell line was confirmed by both immobilizing methods, whereas this MAb had not a noticeable affinity to the MOLT-4 cells. Conclusion: According to the outcomes, the investigated MAb had acceptable affinity and specificity to the target antigens on the cell surface and could be utilized for immuno-detection of CD20-positive intact cells by SPR method. PMID:28761820

Deficient CD4+ T cell priming and regression of CD8+ T cell functionality in virus-infected mice lacking a normal B cell compartment

DEFF Research Database (Denmark)

Christensen, Jan Pravsgaard; Kauffmann, Susanne Ørding; Thomsen, Allan Randrup

2003-01-01

of virus-specific CD4(+) T cells was markedly impaired in B(-/-) mice infected with either virus strain. Thus, our results indicate that B cells play an important role in antiviral immunity not only as Ab producers, but also in promoting an optimal and sustained T cell response. The T cell defects......In this study, we investigate the state of T cell-mediated immunity in B cell-deficient (B(-/-)) mice infected with two strains of lymphocytic choriomeningitis virus known to differ markedly in their capacity to persist. In B(-/-) C57BL mice infected with the more persisting virus, virus......-specific CD8(+) T cells are initially generated that are qualitatively similar to those in wild-type mice. However, although cell numbers are well sustained over time, the capacity to produce cytokines is rapidly impaired. In similarly infected B(-/-) BALB/c mice, virus-specific CD8(+) T cells are completely...

Clinical impact of B-cell depletion with the anti-CD20 antibody rituximab in chronic fatigue syndrome: a preliminary case series

Directory of Open Access Journals (Sweden)

Mella Olav

2009-07-01

Full Text Available Abstract Background Chronic fatigue syndrome (CFS is a disease of unknown aetiology. A patient with CFS had unexpected, marked recovery of CFS symptoms lasting for five months during and after cytotoxic chemotherapy for Hodgkin's disease. We reasoned that the transient CFS recovery was related to methotrexate treatment, which induces immunomodulation in part through B-cell depletion. Methods In a case series, this patient and two additional CFS patients were B-cell depleted by infusion of the monoclonal anti-CD20 antibody rituximab. Results All three had improvement of all CFS symptoms. Patients 1 and 2 had major amelioration from 6 weeks after intervention, patient 3 slight improvement from the same time, but then improved markedly from 26 weeks after intervention. The symptomatic effect lasted until weeks 16, 18 and 44, respectively. At relapse, all were retreated with a single (patient 1 or double rituximab infusion (patients 2 and 3. Again, all three had marked symptom improvement, mimicking their first response. After new symptom recurrence, patients 1 and 2 were given weekly oral methotrexate, patient 1 having effect also from this agent. Patients 1 and 2 were again treated for a third rituximab infusion after new relapse, again with a marked clinical benefit. No unexpected toxicity was seen. Conclusion These observations suggest that B-lymphocytes are involved in CFS pathogenesis for a subset of patients. Benefit for all CFS symptoms, the delayed symptom relief following B-cell depletion, the kinetics of relapses, and the effect also from methotrexate treatment, provide suggestive evidence that B-cells play a significant role in the ongoing clinical features, and that CFS may be amenable to therapeutic interventions aimed at modifying B-cell number and function. More systematic investigations of this therapeutic strategy, and of its biological basis, are now needed.

Preparation and Evaluation of 99mTc-labeled anti-CD11b Antibody Targeting Inflammatory Microenvironment for Colon Cancer Imaging.

Science.gov (United States)

Cheng, Dengfeng; Zou, Weihong; Li, Xiao; Xiu, Yan; Tan, Hui; Shi, Hongcheng; Yang, Xiangdong

2015-06-01

CD11b, an active constituent of innate immune response highly expressed in myeloid-derived suppressor cells (MDSCs), can be used as a marker of inflammatory microenvironment, particularly in tumor tissues. In this research, we aimed to fabricate a (99m)Tc-labeled anti-CD11b antibody as a probe for CD11b(+) myeloid cells in colon cancer imaging with single-photon emission computed tomography (SPECT). In situ murine colon tumor model was established in histidine decarboxylase knockout (Hdc(-/-)) mice by chemicals induction. (99m)Tc-labeled anti-CD11b was obtained with labeling yields of over 30% and radiochemical purity of over 95%. Micro-SPECT/CT scans were performed at 6 h post injection to investigate biodistributions and targeting of the probe. In situ colonic neoplasma as small as 3 mm diameters was clearly identified by imaging; after dissection of the animal, anti-CD11b immunofluorescence staining was performed to identify infiltration of CD11b+ MDSCs in microenvironment of colonic neoplasms. In addition, the images displayed intense signal from bone marrow and spleen, which indicated the origin and migration of CD11b(+) MDSCs in vivo, and these results were further proved by flow cytometry analysis. Therefore, (99m)Tc-labeled anti-CD11b SPECT displayed the potential to facilitate the diagnosis of colon tumor in very early stage via detection of inflammatory microenvironment. © 2014 John Wiley & Sons A/S.

Sandwich iridium complexes with the monoanionic carborane ligand [9-SMe2-7,8-C2B9H10]-

International Nuclear Information System (INIS)

Loginov, D.A.; Vinogradov, M.M.; Perekalin, D.S.; Starikova, Z.A.; Lysenko, K.A.; Petrovskij, P.V.; Kudinov, A.R.

2006-01-01

The reaction of the [(η-9-SMe 2 -7,8-C 2 B 9 H 10 )IrBr 2 ] 2 complex with Tl[Tl(η-7,8-C 2 B 9 H 11 )] afforded the iridacarborane compound (η-9-SMe 2 -7,8-C 2 B 9 H 10 )Ir(η-7,8-C 2 B 9 H 11 ). The cationic complex [Cp*Ir(η-9-SMe 2 -7,8-C 2 B 9 H 10 )] + PF 6 - (Cp* is pentamethylcyclopentadienyl) was synthesized by the reaction of [Cp*IrCl 2 ] 2 with Na[9-SMe 2 -7,8-C 2 B 9 H 10 ]. The structures of (η-9-SMe 2 -7,8-C 2 B 9 H 10 )Ir(η-cod) (cod is 1,5-cyclooctadiene) and [Cp*Ir(η-9-SMe 2 -7,8-C 2 B 9 H 10 ]PF 6 were established by X-ray diffraction [ru

Mass spectrum of spin-1/2 pentaquarks with a c anti c component and their anticipated discovery modes in b-baryon decays

Energy Technology Data Exchange (ETDEWEB)

Ali, Ahmed [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Ahmed, Ishtiaq; Rehman, Abdur [Quaid-i-Azam University Campus, Islamabad (Pakistan). National Centre for Physics; Aslam, M. Jamil [Quaid-i-Azam University, Islamabad (Pakistan). Physics Dept.

2017-04-15

The LHCb discovery of the two baryonic states P{sub c}{sup +}(4380) and P{sub c}{sup +}(4450), having J{sup P}=3/2{sup -} and J{sup P}=5/2{sup +}, respectively, in the process pp → b anti b → Λ{sub b}X, followed by the decay Λ{sub b}→J/ψpK{sup -}, has motivated a number of theoretical models. Interpreting them as compact { anti c[cu][ud]; L_P=0,1} objects, the mass spectroscopy of the J{sup P}=3/2{sup -} and J{sup P}=5/2{sup +} pentaquarks was worked out by us for the pentaquarks in the SU(3){sub F} multiplets, using an effective Hamiltonian based on constituent diquarks and quarks. Their possible discovery modes in b-baryon decays were also given using the heavy quark spin symmetry. In this paper, we calculate the mass spectrum of the hidden c anti c pentaquarks having J{sup P}=(1)/(2){sup ±} for the SU(3){sub F} multiplets and their anticipated discovery modes in b-baryon decays. Some of the P{sub c}{sup +}(J{sup P}=1/2{sup ±}) pentaquarks, produced in the Λ{sub b} decays may have their masses just below the J/ψ p threshold, in which case they should be searched for in the modes P{sub c}{sup +}(J{sup P}=1/2{sup ±})→η{sub c}p,μ{sup +}μ{sup -}p,e{sup +}e{sup -}p.

Complement receptors type 1 (CR1, CD35) and 2 (CR2, CD21) cooperate in the binding of hydrolyzed complement factor 3 (C3i) to human B lymphocytes

DEFF Research Database (Denmark)

Leslie, Robert Graham Quinton; Prodinger, Wolfgang Maria; Nielsen, Claus Henrik

2003-01-01

The C3b-binding receptor, CR1/CD35, supports CR2/CD21-mediated activation of complement by human B lymphocytes, possibly by associating with CR2 to promote or stabilize the binding of hydrolyzed C3 (C3i), the primary component of the AP convertase, C3i-Bb. To evaluate this hypothesis, we examined...... the uptake kinetics and binding equilibria for C3i dimer interaction with human blood cells in the absence and presence of CR1- and CR2-blocking mAb. C3i displayed dual uptake kinetics to B lymphocytes, comprising of rapid binding to CR1 and slower binding to CR2. The forward rate constants (k(1)) for CR1...... and CR2, operating independently, differed ca. 9-fold (k(1)=193+/-9.4 and 22.2+/-6.0 x 10(3) M(-1)s(-1), respectively). Equilibrium binding of C3i to B lymphocytes was also complex, varying in strength by ca. 13-fold over the C3i concentration range examined. The maximum association constant (K(a, max...

Prolonged activation of virus-specific CD8+T cells after acute B19 infection.

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Adiba Isa

2005-12-01

Full Text Available Human parvovirus B19 (B19 is a ubiquitous and clinically significant pathogen, causing erythema infectiosum, arthropathy, transient aplastic crisis, and intrauterine fetal death. The phenotype of CD8+ T cells in acute B19 infection has not been studied previously.The number and phenotype of B19-specific CD8+ T cell responses during and after acute adult infection was studied using HLA-peptide multimeric complexes. Surprisingly, these responses increased in magnitude over the first year post-infection despite resolution of clinical symptoms and control of viraemia, with T cell populations specific for individual epitopes comprising up to 4% of CD8+ T cells. B19-specific T cells developed and maintained an activated CD38+ phenotype, with strong expression of perforin and CD57 and downregulation of CD28 and CD27. These cells possessed strong effector function and intact proliferative capacity. Individuals tested many years after infection exhibited lower frequencies of B19-specific cytotoxic T lymphocytes, typically 0.05%-0.5% of CD8+ T cells, which were perforin, CD38, and CCR7 low.This is the first example to our knowledge of an "acute" human viral infection inducing a persistent activated CD8+ T cell response. The likely explanation--analogous to that for cytomegalovirus infection--is that this persistent response is due to low-level antigen exposure. CD8+ T cells may contribute to the long-term control of this significant pathogen and should be considered during vaccine development.

Prolonged activation of virus-specific CD8+T cells after acute B19 infection.

Directory of Open Access Journals (Sweden)

2005-12-01

Full Text Available BACKGROUND: Human parvovirus B19 (B19 is a ubiquitous and clinically significant pathogen, causing erythema infectiosum, arthropathy, transient aplastic crisis, and intrauterine fetal death. The phenotype of CD8+ T cells in acute B19 infection has not been studied previously. METHODS AND FINDINGS: The number and phenotype of B19-specific CD8+ T cell responses during and after acute adult infection was studied using HLA-peptide multimeric complexes. Surprisingly, these responses increased in magnitude over the first year post-infection despite resolution of clinical symptoms and control of viraemia, with T cell populations specific for individual epitopes comprising up to 4% of CD8+ T cells. B19-specific T cells developed and maintained an activated CD38+ phenotype, with strong expression of perforin and CD57 and downregulation of CD28 and CD27. These cells possessed strong effector function and intact proliferative capacity. Individuals tested many years after infection exhibited lower frequencies of B19-specific cytotoxic T lymphocytes, typically 0.05%-0.5% of CD8+ T cells, which were perforin, CD38, and CCR7 low. CONCLUSION: This is the first example to our knowledge of an "acute" human viral infection inducing a persistent activated CD8+ T cell response. The likely explanation--analogous to that for cytomegalovirus infection--is that this persistent response is due to low-level antigen exposure. CD8+ T cells may contribute to the long-term control of this significant pathogen and should be considered during vaccine development.

Evaluation of cell cycle changes activated by the administration of {sup 177}Lu-DOTA-antiCD20; Evaluacion de cambios en el ciclo celular activados por la administracion de {sup 177}Lu-DOTA-antiCD20

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Ramos B, J. C.

2016-07-01

In the present project, cytometric evaluation of cell cycle changes induced by the {sup 177}Lu-DOTA-antiCD20 thermostatic radiopharmaceutical was performed, in which a cell culture of Raji cells from Burkitts lymphoma were used, which are CD20+; for flow cytometry different parameters were measured in which the cells were synchronized in G0/G1 and G2/M, to calculate the dose to nucleus that were given to the cells the Monte Carlo method was used at a dose interval from 1 to 5 Gy. The purpose of this work is to be able to observe by flow cytometry the arrest in the cell cycle with a lower dose interval than the one applied in other papers. (Author)

Prolonged activation of virus-specific CD8+T cells after acute B19 infection

DEFF Research Database (Denmark)

Isa, Adiba; Kasprowicz, Victoria; Norbeck, Oscar

2005-01-01

BACKGROUND: Human parvovirus B19 (B19) is a ubiquitous and clinically significant pathogen, causing erythema infectiosum, arthropathy, transient aplastic crisis, and intrauterine fetal death. The phenotype of CD8+ T cells in acute B19 infection has not been studied previously. METHODS AND FINDINGS......: The number and phenotype of B19-specific CD8+ T cell responses during and after acute adult infection was studied using HLA-peptide multimeric complexes. Surprisingly, these responses increased in magnitude over the first year post-infection despite resolution of clinical symptoms and control of viraemia......, with T cell populations specific for individual epitopes comprising up to 4% of CD8+ T cells. B19-specific T cells developed and maintained an activated CD38+ phenotype, with strong expression of perforin and CD57 and downregulation of CD28 and CD27. These cells possessed strong effector function...

Construction and characterization of an anti-CD20 mAb nanocomb with exceptionally excellent lymphoma-suppressing activity

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Li H

2015-07-01

Full Text Available Hua-Fei Li,1–3,* Cong Wu,4,* Ting Chen,5,* Ge Zhang,1 He Zhao,1 Chang-Hong Ke,1 Zheng Xu21International Joint Cancer Institute, Translation Medicine Institute, 2Planning Division, Scientific Research Department, 3Tumor Immunology and Gene Therapy Center, Eastern Hepatobiliary Surgery Hospital, 4Department of Laboratory Diagnosis, Changhai Hospital, 5Department of Cardiology, Changhai Hospital, the Second Military Medical University, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: The CD20-directed monoclonal antibody rituximab (RTX established a new era in the treatment of non-Hodgkin lymphoma (NHL; however, suboptimal response and/or resistance to RTX still limit its clinical merits. Although four effector mechanisms are validated to participate in CD20-based immunotherapy, including complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity, caspase-dependent apoptosis, and lysosome-mediated programmed cell death (PCD, they could hardly be synchronously activated by any anti-CD20 mAb or mAb derivative until now. Herein, a novel mAb nanocomb (polyethylenimine polymer–RTX–tositumomab [PPRT nanocomb] was firstly constructed through mass arming two different anti-CD20 mAbs (RTX and tositumomab to one polymer by nanotechnology. Comparing with free mAbs, PPRT nanocomb possesses a comparable binding ability and reduced “off-rate” to surface CD20 of NHL cells. When treated by PPRT nanocomb, the caspase-dependent apoptosis was remarkably enhanced except for concurrently eliciting complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity, and lysosome-mediated PCD. Besides, “cross-cell link”-assisted homotypic adhesion by PPRT nanocomb further enhanced the susceptibility to PCD of lymphoma cells. Pharmacokinetic assays revealed that PPRT nanocomb experienced a relatively reduced clearance from peripheral blood compared with free antibodies. With

Reduced CD5(+) CD24(hi) CD38(hi) and interleukin-10(+) regulatory B cells in active anti-neutrophil cytoplasmic autoantibody-associated vasculitis permit increased circulating autoantibodies.

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Aybar, L T; McGregor, J G; Hogan, S L; Hu, Y; Mendoza, C E; Brant, E J; Poulton, C J; Henderson, C D; Falk, R J; Bunch, D O

2015-05-01

Pathogenesis of anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis is B cell-dependent, although how particular B cell subsets modulate immunopathogenesis remains unknown. Although their phenotype remains controversial, regulatory B cells (Bregs ), play a role in immunological tolerance via interleukin (IL)-10. Putative CD19(+) CD24(hi) CD38(hi) and CD19(+) CD24(hi) CD27(+) Bregs were evaluated in addition to their CD5(+) subsets in 69 patients with ANCA-associated vasculitis (AAV). B cell IL-10 was verified by flow cytometry following culture with CD40 ligand and cytosine-phosphate-guanosine (CpG) DNA. Patients with active disease had decreased levels of CD5(+) CD24(hi) CD38(hi) B cells and IL-10(+) B cells compared to patients in remission and healthy controls (HCs). As IL-10(+) and CD5(+) CD24(hi) CD38(hi) B cells normalized in remission within an individual, ANCA titres decreased. The CD5(+) subset of CD24(hi) CD38(hi) B cells decreases in active disease and rebounds during remission similarly to IL-10-producing B cells. Moreover, CD5(+) B cells are enriched in the ability to produce IL-10 compared to CD5(neg) B cells. Together these results suggest that CD5 may identify functional IL-10-producing Bregs . The malfunction of Bregs during active disease due to reduced IL-10 expression may thus permit ANCA production. © 2014 British Society for Immunology.

Elimination of self-reactive CD8+, but not CD4+, T cells by a peripheral immune mechanism

International Nuclear Information System (INIS)

Rammensee, H.G.; Huegin, D.

1990-01-01

Unirradiated (BALB/c X B6)F1 recipients of lymphocytes from either parent or (B6 X DBA/2)F2 recipients of DBA/2 parental lymphocytes specifically remove the function of donor-derived F1-reactive CTL from the spleen, since such cells could not be recovered 1 week after injection. However, donor-derived CTL specific for third-party antigens, as well as donor-derived F1-reactive CD4+ T cells could be recovered. In contrast, CTL in spleens from recipients sublethally irradiated prior to injections consisted predominantly of F1-reactive CTL in all strain combinations tested. Athymic BALB/c nude mice grafted with fetal thymus of B6 develop a T cell compartment tolerant of BALB/c and B6, like (BALB/c X B6)F1 animals. However, unlike the F1 mice, the thymus-grafted nude mice were not able to eliminate B6-reactive lymphocytes after injection of normal BALB/c spleen cells. Our data indicate the existence of a peripheral immune mechanism capable of selectively eliminating self-reactive CD8+ CTL, but not CD4+, T cells. This mechanism requires self antigen expressed on radiosensitive cells. The presence of T cells tolerant to self antigen by thymic negative selection is not sufficient and perhaps not required. Most likely, this mechanism is involved in the relative resistance to lethal GVHR mediated by parental CD8+ T cells in parent-into-F1 situations

Exposure of a distinct PDCA-1+ (CD317 B cell population to agonistic anti-4-1BB (CD137 inhibits T and B cell responses both in vitro and in vivo.

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Dass S Vinay

Full Text Available 4-1BB (CD137 is an important T cell activating molecule. Here we report that it also promotes development of a distinct B cell subpopulation co-expressing PDCA-1. 4-1BB is expressed constitutively, and its expression is increased when PDCA-1(+ B cells are activated. We found that despite a high level of surface expression of 4-1BB on PDCA-1(+ B cells, treatment of these cells with agonistic anti-4-1BB mAb stimulated the expression of only a few activation markers (B7-2, MHC II, PD-L2, cytokines (IL-12p40/p70, and chemokines (MCP-1, RANTES, as well as sTNFR1, and the immunosuppressive enzyme, IDO. Although the PDCA-1(+ B cells stimulated by anti-4-1BB expressed MHC II at high levels and took up antigens efficiently, Ig class switching was inhibited when they were pulsed with T-independent (TI or T-dependent (TD Ags and adoptively transferred into syngeneic recipients. Furthermore, when anti-4-1BB-treated PDCA-1(+ B cells were pulsed with OVA peptide and combined with Vα2(+CD4(+ T cells, Ag-specific cell division was inhibited both in vitro and in vivo. Our findings suggest that the 4-1BB signal transforms PDCA-1(+ B cells into propagators of negative immune regulation, and establish an important role for 4-1BB in PDCA-1(+ B cell development and function.

CD117 expression on blast cells in acute myeloid leukemia

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Goryainova N.V.

2015-09-01

Full Text Available The aim of the present work was to analyze the frequency of CD117 (c-KIT antigen expression on the blast cells in acute myeloid leukemia (AML, evaluation of the presence of the relationship between the expression of the c-KIT and leukemia according to the FAB classification and definition of co-expression of the antigen CD117, antigens CD33 and CD34. The data of 47 patients with AML were diagnosed. M0 AML variant was established in 3 (6% patients, M1 – in 2 (4%, M2 – in 9 (20%, M4 – in 22 (47% and M5 – in 11 (23%. For immunophenotypic stu¬dies monoclonal antibodies (mAb that detect antigens of anti-CD34, anti-CD33 and anti-CD117 (Becton Dickinson, USA were used. The presence of the antigen CD117 was detected in 39 people, accounting for 83% of all surveyed. Antigen c-KIT was present in 48.117.0% cells on average: in all 3 cases – AML M0, in2 cases of AML M1, in 6 cases – AML M2, 20 of 22 cases – AML M4 and in 8 of 11 AML M5 cases. Average levels of CD117 in investigated leukemia cases statistically differed significantly (p=0.0067. Among 39 CD117- positive patients in 25 (53% co-expression of CD117+/CD34+ was revealed. Expression of CD117+/CD34- was observed in 14 cases (30%, CD117-/CD34+ – in 4 cases (8,5%, CD117-/CD34- – in 4 cases (8.5%. CD34 had of 64% of cells of myeloid origin. A high positive cor¬relation between expression of CD117 and CD34 (r=+0,5169 was determined, being statistically significant (p0,0067.

Abalone visceral extract inhibit tumor growth and metastasis by modulating Cox-2 levels and CD8+ T cell activity

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II Kim Jae

2010-10-01

Full Text Available Abstract Background Abalone has long been used as a valuable food source in East Asian countries. Although the nutritional importance of abalone has been reported through in vitro and in vivo studies, there is little evidence about the potential anti-tumor effects of abalone visceral extract. The aim of the present study is to examine anti-tumor efficacy of abalone visceral extract and to elucidate its working mechanism. Methods In the present study, we used breast cancer model using BALB/c mouse-derived 4T1 mammary carcinoma and investigated the effect of abalone visceral extract on tumor development. Inhibitory effect against tumor metastasis was assessed by histopathology of lungs. Cox-2 productions by primary and secondary tumor were measured by real-time RT-PCR and immunoblotting (IB. Proliferation assay based on [3H]-thymidine incorporation and measurement of cytokines and effector molecules by RT-PCR were used to confirm tumor suppression efficacy of abalone visceral extract by modulating cytolytic CD8+ T cells. The cytotoxicity of CD8+ T cell was compared by JAM test. Results Oral administration of abalone visceral extract reduced tumor growth (tumor volume and weight and showed reduced metastasis as confirmed by decreased level of splenomegaly (spleen size and weight and histological analysis of the lung metastasis (gross analysis and histological staining. Reduced expression of Cox-2 (mRNA and protein from primary tumor and metastasized lung was also detected. In addition, treatment of abalone visceral extract increased anti-tumor activities of CD8+ T cells by increasing the proliferation capacity and their cytolytic activity. Conclusions Our results suggest that abalone visceral extract has anti-tumor effects by suppressing tumor growth and lung metastasis through decreasing Cox-2 expression level as well as promoting proliferation and cytolytic function of CD8+ T cells.

Abalone visceral extract inhibit tumor growth and metastasis by modulating Cox-2 levels and CD8+ T cell activity.

Science.gov (United States)

Lee, Choong-Gu; Kwon, Ho-Keun; Ryu, Jae Ha; Kang, Sung Jin; Im, Chang-Rok; Ii Kim, Jae; Im, Sin-Hyeog

2010-10-20

Abalone has long been used as a valuable food source in East Asian countries. Although the nutritional importance of abalone has been reported through in vitro and in vivo studies, there is little evidence about the potential anti-tumor effects of abalone visceral extract. The aim of the present study is to examine anti-tumor efficacy of abalone visceral extract and to elucidate its working mechanism. In the present study, we used breast cancer model using BALB/c mouse-derived 4T1 mammary carcinoma and investigated the effect of abalone visceral extract on tumor development. Inhibitory effect against tumor metastasis was assessed by histopathology of lungs. Cox-2 productions by primary and secondary tumor were measured by real-time RT-PCR and immunoblotting (IB). Proliferation assay based on [3H]-thymidine incorporation and measurement of cytokines and effector molecules by RT-PCR were used to confirm tumor suppression efficacy of abalone visceral extract by modulating cytolytic CD8+ T cells. The cytotoxicity of CD8+ T cell was compared by JAM test. Oral administration of abalone visceral extract reduced tumor growth (tumor volume and weight) and showed reduced metastasis as confirmed by decreased level of splenomegaly (spleen size and weight) and histological analysis of the lung metastasis (gross analysis and histological staining). Reduced expression of Cox-2 (mRNA and protein) from primary tumor and metastasized lung was also detected. In addition, treatment of abalone visceral extract increased anti-tumor activities of CD8+ T cells by increasing the proliferation capacity and their cytolytic activity. Our results suggest that abalone visceral extract has anti-tumor effects by suppressing tumor growth and lung metastasis through decreasing Cox-2 expression level as well as promoting proliferation and cytolytic function of CD8+ T cells.

Rituximab chimeric anti-CD20 monoclonal antibody treatment for adult refractory idiopathic thrombocytopenic purpura

DEFF Research Database (Denmark)

Braendstrup, Peter; Bjerrum, Ole W; Nielsen, Ove J

2005-01-01

. Recent studies have shown that rituximab, a chimeric anti-CD20 monoclonal antibody, is useful in the treatment of these patients, with overall response rates of about 50%. Most published reports have included a small number patients including case reports. The present study reports the results...

Expression of fusion IL2-B7.1(IgV+C) and effects on T lymphocytes.

Science.gov (United States)

Kong, Linghong; Li, Yaochen; Yang, Ye; Li, Kangsheng

2007-12-01

The search for an effective immunotherapeutic treatment for tumors is an important area of cancer research. To prepare a more effective form of the bifunctional fusion protein IL2-B7.1(IgV+C) and analyze its effect on the stimulation of T lymphocyte proliferation, we used DNAStar 5.03 software to predict the structural diversity and biochemical character of IL2-B7.1(IgV+C). We then prepared fusion protein IL2-B7.1(IgV+C) by establishing its prokaryotic expression system, and tested its effect on the stimulation of T lymphocytes in vitro. The results indicated that IL2-B7.1(IgV+C) correctly formed a secondary structure in which both IL2 and B7.1(IgV+C) maintained their original hydrophilicity and epitopes. Western blot analysis revealed that IL2-B7.1(IgV+C) was efficiently expressed. Our analysis of CTLL-2 and T-cell proliferation showed that recombinant human (rh) IL2-B7.1(IgV+C) exerted the combined stimulating effects of both rhIL2 and rh B7.1(IgV+C) on cell proliferation, and that these effects could be blocked by adding either anti-IL2 or anti-B7.1 monoclonal antibodies. A >2-fold increase in [3H]TdR incorporation compared with that of cells treated with recombinant protein IL2, or B7.1(IgV+C) alone, revealed that rhIL2-B7.1(IgV+C) had dose-dependent synergetic effects on T-cell activation in the presence of anti-CD3 monoclonal antibody. We concluded that the augmented potency of rhIL2-B7.1(IgV+C) resulted in a stronger stimulation of T-cell proliferation than either rhB7.1(IgV+C) or rhIL2 alone.

Transfer of allogeneic CD4+ T cells rescues CD8+ T cells in anti-PD-L1–resistant tumors leading to tumor eradication

Science.gov (United States)

Arina, Ainhoa; Karrison, Theodore; Galka, Eva; Schreiber, Karin; Weichselbaum, Ralph R.; Schreiber, Hans

2017-01-01

Adoptively transferred CD8+ T cells can stabilize the size of solid tumors over long periods of time by exclusively recognizing antigen cross-presented on tumor stroma. However, these tumors eventually escape T cell–mediated growth control. The aim of this study was to eradicate such persistent cancers. In our model, the SIYRYYGL antigen is expressed by cancer cells that lack the MHC-I molecule Kb needed for direct presentation, but the antigen is picked up and cross-presented by tumor stroma. A single injection of antigen-specific 2C CD8+ T cells caused long-term inhibition of tumor growth, but without further intervention, tumors started to progress after approximately 3 months. Escape was associated with reduced numbers of circulating 2C cells. Tumor-infiltrating 2C cells produced significantly less TNFα and expressed more of the “exhaustion” markers PD-1 and Tim-3 than T cells from lymphoid organs. High-dose local ionizing radiation, depletion of myeloid-derived suppressor cells, infusions of additional 2C cells, and antibodies blocking PD-L1 did not prevent tumor escape. In contrast, adoptive transfer of allogeneic CD4+ T cells restored the numbers of circulating Ag-specific CD8+ T cells and their intratumoral function, resulting in tumor eradication. These CD4+ T cells had no antitumor effects in the absence of CD8+ T cells and recognized the alloantigen cross-presented on tumor stroma. CD4+ T cells might also be effective in cancer patients when PD1/PD-L1 blockade does not rescue intratumoral CD8+ T-cell function and tumors persist. PMID:28077434

Participation of CD11b and F4/80 molecules in the conjunctival eosinophilia of experimental allergic conjunctivitis.

Science.gov (United States)

Fukushima, Atsuki; Ishida, Waka; Ojima, Ayako; Kajisako, Mina; Sumi, Tamaki; Yamada, Jun; Tsuru, Emi; Miyazaki, Jun-ichi; Tominaga, Akira; Yagita, Hideo

2010-01-01

CD11b and F4/80 are macrophage surface markers. How these molecules participate in allergic eosinophil infiltration remains unclear. We examined the roles CD11b and F4/80 play in the conjunctival eosinophil infiltration associated with experimental allergic conjunctivitis. Ragweed-immunized BALB/c mice were challenged with ragweed in eye drops to induce conjunctival eosinophil infiltration. The effect of challenge on conjunctival CD11b+ and F4/80+ cell numbers was determined by immunohistochemistry. In the same model, blocking anti-CD11b and anti-F4/80 Abs were injected intraperitoneally during the induction or the effector phase, or subconjunctivally 2 h before challenge, to determine their effect on challenge-induced conjunctival eosinophilia. To examine whether eosinophils express CD11b and F4/80 molecules, splenocytes from IL-5 gene-electroporated mice were subjected to flow cytometric analysis. To clarify the involvement of CD11b and F4/80 in conjunctival eosinophil infiltration, mice were intraperitoneally injected with anti-CD11b and anti-F4/80 Abs and then subconjunctivally injected with eotaxin to induce conjunctival eosinophilia. Ragweed challenge elevated conjunctival CD11b+ and F4/80+ cell numbers. Systemic anti-CD11b and anti-F4/80 Ab treatments during the effector phase, but not in either the induction phase or the local injection of Ab, suppressed conjunctival eosinophil infiltration in ragweed-induced conjunctivitis. Most splenic eosinophils from IL-5 gene-introduced mice expressed CD11b and F4/80. Systemic anti-CD11b and anti-F4/80 Ab treatment suppressed conjunctival eosinophilia induced by subconjunctival eotaxin injection. CD11b and F4/80 appear to participate in conjunctival eosinophil infiltration in allergic conjunctivitis. Their involvement in conjunctival eosinophilia appears to be due to their expression on eosinophils rather than on macrophages. 2009 S. Karger AG, Basel.

27-Oxygenated cholesterol induces expression of CXCL8 in macrophages via NF-κB and CD88

Energy Technology Data Exchange (ETDEWEB)

Kim, Sun-Mi, E-mail: lala1647@hanmail.net [Department of Pharmacology, Pusan National University, School of Medicine, Yangsan, Gyeongnam 626-870 (Korea, Republic of); Lee, Chung Won, E-mail: vasculardoctorlee@gmail.com [Department of Thoracic and Cardiovascular Surgery, Pusan National University Hospital, Pusan 602-739 (Korea, Republic of); Kim, Bo-Young, E-mail: kimboyoung@pusan.ac.kr [Department of Pharmacology, Pusan National University, School of Medicine, Yangsan, Gyeongnam 626-870 (Korea, Republic of); Jung, Young-Suk, E-mail: youngjung@pusan.ac.kr [College of Pharmacy, Pusan National University, Busan 609-735 (Korea, Republic of); Eo, Seong-Kug, E-mail: vetvirus@chonbuk.ac.kr [College of Veterinary Medicine and Bio-Safety Research Institute, Chonbuk National University, Iksan, Jeonbuk 570-752 (Korea, Republic of); Park, Young Chul, E-mail: ycpark@pusan.ac.kr [Department of Microbiology & Immunology, Pusan National University, School of Medicine, Yangsan, Gyeongnam 626-870 (Korea, Republic of); Kim, Koanhoi, E-mail: koanhoi@pusan.ac.kr [Department of Pharmacology, Pusan National University, School of Medicine, Yangsan, Gyeongnam 626-870 (Korea, Republic of)

2015-08-07

We attempted to determine the effects of a milieu rich in cholesterol molecules on expression of chemokine CXCL8. A high-cholesterol diet led to an increased transcription of the IL-8 gene in the arteries and elevated levels of CXCL8 in sera of ApoE{sup −/−} mice, compared with those of wild-type C57BL/6 mice. Treatment of THP-1 monocyte/macrophage cells with 27-hydroxycholesterol (27OHChol) resulted in transcription of the IL-8 gene and increased secretion of its corresponding gene product whereas cholesterol did not induce expression of CXCL8 in THP-1 cells. 27OHChol-induced transcription of the IL-8 gene was blocked by cycloheximide, but not by polymyxin B. Treatment of THP-1 cells with 27OHChol caused translocation of p65 NF-κB subunit into the nucleus and up-regulation of CD88. Inhibition of NF-κB and CD88 using SN50 and W-54011, respectively, resulted in reduced transcription of the IL-8 gene and attenuated secretion of CXCL8 induced by 27OHChol. We propose that oxidatively modified cholesterol like 27OHChol, rather than cholesterol, is responsible for sustained expression of CXCL8 in monocytes/macrophages in atherosclerotic arteries. - Highlights: • Consumption of a high-cholesterol diet leads to increased CXCL8 expression in ApoE{sup −/−} mice. • 27OHChol, but not cholesterol, up-regulates expression of CXCL8 in macrophages. • 27OHChol enhances nuclear translocation of NF-κB and expression of CD88 in macrophages. • Inhibition of NF-κB or CD88 results in decreased CXCL8 expression induced by 27OHChol. • 27OHChol up-regulates CXCL8 expression via NF-κB and CD88 in macrophages.

Antigenic modulation limits the effector cell mechanisms employed by type I anti-CD20 monoclonal antibodies.

Science.gov (United States)

Tipton, Thomas R W; Roghanian, Ali; Oldham, Robert J; Carter, Matthew J; Cox, Kerry L; Mockridge, C Ian; French, Ruth R; Dahal, Lekh N; Duriez, Patrick J; Hargreaves, Philip G; Cragg, Mark S; Beers, Stephen A

2015-03-19

Following the success of rituximab, 2 other anti-CD20 monoclonal antibodies (mAbs), ofatumumab and obinutuzumab, have entered clinical use. Ofatumumab has enhanced capacity for complement-dependent cytotoxicity, whereas obinutuzumab, a type II mAb, lacks the ability to redistribute into lipid rafts and is glycoengineered for augmented antibody-dependent cellular cytotoxicity (ADCC). We previously showed that type I mAbs such as rituximab have a propensity to undergo enhanced antigenic modulation compared with type II. Here we assessed the key effector mechanisms affected, comparing type I and II antibodies of various isotypes in ADCC and antibody-dependent cellular-phagocytosis (ADCP) assays. Rituximab and ofatumumab depleted both normal and leukemic human CD20-expressing B cells in the mouse less effectively than glycoengineered and wild-type forms of obinutuzumab, particularly when human immunoglobulin G1 (hIgG1) mAbs were compared. In contrast to mouse IgG2a, hIgG1 mAbs were ineffective in ADCC assays with murine natural killer cells as effectors, whereas ADCP was equivalent for mouse IgG2a and hIgG1. However, rituximab's ability to elicit both ADCC and ADCP was reduced by antigenic modulation, whereas type II antibodies remained unaffected. These data demonstrate that ADCP and ADCC are impaired by antigenic modulation and that ADCP is the main effector function employed in vivo. © 2015 by The American Society of Hematology.

Exposure of Human CD8+ T Cells to Type-2 Cytokines Impairs Division and Differentiation and Induces Limited Polarization

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Annette Fox

2018-05-01

Full Text Available Effector CD8+ T cells generally produce type-1 cytokines and mediators of the perforin/granzyme cytolytic pathway, yet type-2-polarized CD8+ cells (Tc2 are detected in type-2 (T2 cytokine-driven diseases such as asthma. It is unclear whether T2 cytokine exposure during activation is sufficient to polarize human CD8+ T cells. To address this question, a protocol was developed for high-efficiency activation of human CD8+ T cells in which purified single cells or populations were stimulated with plate-bound anti-CD3 and anti-CD11a mAb for up to 8 days in T2 polarizing or neutral conditions, before functional analysis. Activation of CD8+ naïve T cells (TN in T2 compared with neutral conditions decreased the size of single-cell clones, although early division kinetics were equivalent, indicating an effect on overall division number. Activation of TN in T2 conditions followed by brief anti-CD3 mAb restimulation favored expression of T2 cytokines, GATA3 and Eomes, and lowered expression of type-1 cytokines, Prf1, Gzmb, T-BET, and Prdm1. However, IL-4 was only weakly expressed, and PMA and ionomycin restimulation favored IFN-γ over IL-4 expression. Activation of TN in T2 compared with neutral conditions prevented downregulation of costimulatory (CD27, CD28 and lymph-node homing receptors (CCR7 and CD95 acquisition, which typically occur during differentiation into effector phenotypes. CD3 was rapidly and substantially induced after activation in neutral, but not T2 conditions, potentially contributing to greater division and differentiation in neutral conditions. CD8+ central memory T cells (TCM were less able to enter division upon reactivation in T2 compared with neutral conditions, and were more refractory to modulating IFN-γ and IL-4 production than CD8+ TN. In summary, while activation of TN in T2 conditions can generate T2 cytokine-biased cells, IL-4 expression is weak, T2 bias is lost upon strong restimulation, differentiation, and division

A reversion of an IL2RG mutation in combined immunodeficiency providing competitive advantage to the majority of CD8+ T cells.

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Kuijpers, Taco W; van Leeuwen, Ester M M; Barendregt, Barbara H; Klarenbeek, Paul; aan de Kerk, Daan J; Baars, Paul A; Jansen, Machiel H; de Vries, Niek; van Lier, René A W; van der Burg, Mirjam

2013-07-01

Mutations in the common gamma chain (γc, CD132, encoded by the IL2RG gene) can lead to B(+)T(-)NK(-) X-linked severe combined immunodeficiency, as a consequence of unresponsiveness to γc-cytokines such as interleukins-2, -7 and -15. Hypomorphic mutations in CD132 may cause combined immunodeficiencies with a variety of clinical presentations. We analyzed peripheral blood mononuclear cells of a 6-year-old boy with normal lymphocyte counts, who suffered from recurrent pneumonia and disseminated mollusca contagiosa. Since proliferative responses of T cells and NK cells to γc -cytokines were severely impaired, we performed IL2RG gene analysis, showing a heterozygous mutation in the presence of a single X-chromosome. Interestingly, an IL2RG reversion to normal predominated in both naïve and antigen-primed CD8(+) T cells and increased over time. Only the revertant CD8(+) T cells showed normal expression of CD132 and the various CD8(+) T cell populations had a different T-cell receptor repertoire. Finally, a fraction of γδ(+) T cells and differentiated CD4(+)CD27(-) effector-memory T cells carried the reversion, whereas NK or B cells were repeatedly negative. In conclusion, in a patient with a novel IL2RG mutation, gene-reverted CD8(+) T cells accumulated over time. Our data indicate that selective outgrowth of particular T-cell subsets may occur following reversion at the level of committed T progenitor cells.

Interaction between exo-nido-ruthenacarborane [Cl(Ph3P)2Ru]-5,6,10-(μ-H)3-10-H-7,8-C2B9H8 and bromine

International Nuclear Information System (INIS)

Timofeev, S.V.; Lobanova, I.A.; Petrovskij, P.V.; Starikova, Z.A.; Bregadze, V.I.

2001-01-01

Interaction between exo-nido-ruthenacarborane [Cl(Ph 3 P) 2 Ru]-5,6,10-(μ-H) 3 -10-H-7,8-C 2 B 9 H 8 with bromine in CH 2 Cl 2 solutions at 0 deg C studied using the methods of elementary analysis, NMR, IR spectroscopy and X-ray diffraction analysis. It was ascertained that the reaction gives rise to bromine atom substitution for chlorine atom in octahedral surrounding of ruthenium atom with formation of complex [Br(Ph 3 P) 2 Ru]-5,6,10-(μ-H) 3 -10-H-7,8-C 2 B 9 H 8 . The complex is crystallized in monoclinic crystal system with the following unit cell parameters a = 12.592 (1), b = 20.687 (2), c = 16.628 (2) A, β = 94.372 (3) deg, sp. gr. P2 1 /n, Z = 4. Coordination octahedron of ruthenium atom is formed by three hydrogen atoms bound with boron atoms in one triangular face of carborane, two phosphorus atoms and one bromine atom [ru

Syntheses, and crystal and electronic structures of the new Zintl phases Na2ACdSb2 and K2ACdSb2 (A=Ca, Sr, Ba, Eu, Yb): Structural relationship with Yb2CdSb2 and the solid solutions Sr2-xAxCdSb2, Ba2-xAxCdSb2 and Eu2-xYbxCdSb2

International Nuclear Information System (INIS)

Saparov, Bayrammurad; Saito, Maia; Bobev, Svilen

2011-01-01

Presented are the details of the syntheses, crystal and electronic structures of a new family of Zintl phases Na 2 ACdSb 2 and K 2 ACdSb 2 (A=Ca, Sr, Ba, Eu, Yb), as well as the solid solutions Sr 2-x A x CdSb 2 , Ba 2-x A x CdSb 2 and Eu 2-x Yb x CdSb 2 . The structures of Na 2 ACdSb 2 and K 2 ACdSb 2 (A=Ca, Sr, Ba, Eu, Yb) were determined to be of a new type with the non-centrosymmetric space group Pmc2 1 (no. 26), Pearson symbol oP12, with lattice parameters a=4.684(1)-4.788(1) A; b=9.099(3)-9.117(2) A; c=7.837(1)-8.057(2) A for the Na 2 ACdSb 2 series, and a=4.6637(9)-5.0368(8) A; b=9.100(2)-9.8183(15) A; and c=7.7954(15)-8.4924(13) A for K 2 ACdSb 2 , respectively. The solid solutions Sr 2-x A x CdSb 2 , Ba 2-x A x CdSb 2 and Eu 2-x Yb x CdSb 2 (x∼1) are isostructural and isoelectronic to the recently reported Yb 2 CdSb 2 (space group Cmc2 1 (no. 36), Pearson symbol cP20). All discussed structures are based upon CdSb 2 4- polyanionic layers, similar to the ones observed in Yb 2 CdSb 2 , with various alkali- and/or alkaline-earth cations coordinated to them. Magnetic susceptibility and Seebeck coefficient measurements on selected Eu 2-x Yb x CdSb 2 samples, taken at low temperatures up to 300 K, are also reported. -- Graphical abstract: The quaternary Zintl phases Na 2 ACdSb 2 and K 2 ACdSb 2 (A=Ca, Sr, Ba, Eu, Yb) with novel layered structures have been synthesized for the first time and structurally characterized by single-crystal X-ray diffraction. Reported as well are the results from crystallographic and property studies of the closely related solid solutions Sr 2-x A x CdSb 2 , Ba 2-x A x CdSb 2 (x∼1), and Eu 2-x Yb x CdSb 2 (1 2 ACdSb 2 and K 2 ACdSb 2 (A=Ca, Sr, Ba, Eu, Yb) are new quaternary Zintl phases. → Sr 2-x A x CdSb 2 , Ba 2-x A x CdSb 2 (x∼1), and Eu 2-x Yb x CdSb 2 (1 4 tetrahedra. → Eu 2-x Yb x CdSb 2 (1< x<2) exhibit high Seebeck coefficient (217 μV/K at RT).

Relationship of PCNA, C-erbB2 and CD44s expression with tumor grade and stage in urothelial carcinomas of the bladder

Science.gov (United States)

Yıldırım, Ayhan; Kösem, Mustafa; Sayar, İlyas; Gelincik, İbrahim; Yavuz, Alparslan; Bozkurt, Aliseydi; Erkorkmaz, Ünal; Bayram, İrfan

2014-01-01

In the present study, the intention was to reveal the relationship of histological grade and stage with c-erbB2, CD44s, and PCNA immunoreactivity in bladder urothelial carcinomas (UC). In our study, we evaluated 46 items of transurethral resection material of patients submitted by YYU Faculty of Medicine, Main Department of Pathology, with a mass revealed in their bladder after clinical and radiological studies at our laboratories and who were diagnosed with urothelial carcinomas. PCNA, c-erbB2, and CD44s were applied in an immunohistochemical manner comprised from nine low-malignant potential papillary urothelial neoplasia, 23 low-grade papillary urothelial carcinoma, and 14 high-grade papillary urothelial carcinoma. Immunostaining was scored according to the percentage of positive cells. The immunohistochemical study demonstrated that the c-erbB2 and PCNA staining ratio increased when an increase occurred in stage and grade. The CD44s staining ratio decreased. C-erbB2, PCNA, and CD44s appear to be a useful marker in the assessment of the prognosis and treatment options in urothelial carcinomas. PMID:25035774

Evaluation of cell death mechanisms activated by the administration of the theranostics radiopharmaceutical "1"7"7Lu-DOTA-anti-CD20 in a dose range of 1-5 Gy

International Nuclear Information System (INIS)

Martinez V, B. E.

2016-01-01

Radio-immunotherapy with anti-CD20 antibodies significantly increases the rate of remission in patients with CD20 over expressing B-cell lymphomas. Radio-labeled antibodies directed to surface antigens allow delivering scaled doses of radiation to specific targets thus limiting the dose to healthy tissue. Anti-CD20 causes cell death by two major pathways; activating the immune system to destroy malignant cells and inducing the activation of cell death pathways. The "1"7"7Lu is a beta particle emitter (max. 0.497 MeV) with a maximum soft tissue reach of 0.7 mm and a half-life of 6.7 days. Several clinical studies have established a maximum tolerated dose (45m Ci/m"2) for "1"7"7Lu-DOTA-rituximab, which shows a favorable clinical response without hematological toxicity. However, the molecular mechanisms of synergistic activation of anti-CD20 and radionuclide have not been studied. In this work we evaluated by flow cytometry, the activation kinetics of the cell death mechanisms induced by the treatment with "1"7"7Lu-DOTA-anti-CD20 from non-Hod king lymphoma cells (Raji). The absorbed radiation dose delivered to the cell nucleus was calculated by Monte Carlo simulation, considering the contribution of the beta emissions of the radiopharmaceutical present in the cell membrane and surrounding environment, as well as crossfire. This work shows that the application of radiation doses of 1 to 5 Gy of the radiopharmaceutical "1"7"7Lu-DOTA-anti-CD20 are sufficient to induce cell death by apoptosis and arrest of the cell cycle. The combination of these factors (continuous delivery of radiation activation of repair mechanisms and increased radio-sensitivity) causes acute activation of the apoptotic program resulting in significant cell death after 96 h of treatment. The temporal analysis of cell death suggests the early activation of apoptosis that is counteracted by the activation of repair processes caused by sustained irradiation, which leads to cell arrest and increases

Anti-HER2 CD4(+) T-helper type 1 response is a novel immune correlate to pathologic response following neoadjuvant therapy in HER2-positive breast cancer.

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Datta, Jashodeep; Berk, Erik; Xu, Shuwen; Fitzpatrick, Elizabeth; Rosemblit, Cinthia; Lowenfeld, Lea; Goodman, Noah; Lewis, David A; Zhang, Paul J; Fisher, Carla; Roses, Robert E; DeMichele, Angela; Czerniecki, Brian J

2015-05-23

A progressive loss of circulating anti-human epidermal growth factor receptor-2/neu (HER2) CD4(+) T-helper type 1 (Th1) immune responses is observed in HER2(pos)-invasive breast cancer (IBC) patients relative to healthy controls. Pathologic complete response (pCR) following neoadjuvant trastuzumab and chemotherapy (T + C) is associated with decreased recurrence and improved prognosis. We examined differences in anti-HER2 Th1 responses between pCR and non-pCR patients to identify modifiable immune correlates to pathologic response following neoadjuvant T + C. Anti-HER2 Th1 responses in 87 HER2(pos)-IBC patients were examined using peripheral blood mononuclear cells pulsed with 6 HER2-derived class II peptides via IFN-γ ELISPOT. Th1 response metrics were anti-HER2 responsivity, repertoire (number of reactive peptides), and cumulative response across 6 peptides (spot-forming cells [SFC]/10(6) cells). Anti-HER2 Th1 responses of non-pCR patients (n = 4) receiving adjuvant HER2-pulsed type 1-polarized dendritic cell (DC1) vaccination were analyzed pre- and post-immunization. Depressed anti-HER2 Th1 responses observed in treatment-naïve HER2(pos)-IBC patients (n = 22) did not improve globally in T + C-treated HER2(pos)-IBC patients (n = 65). Compared with adjuvant T + C receipt, neoadjuvant T + C - utilized in 61.5 % - was associated with higher anti-HER2 Th1 repertoire (p = 0.048). While pCR (n = 16) and non-pCR (n = 24) patients did not differ substantially in demographic/clinical characteristics, pCR patients demonstrated dramatically higher anti-HER2 Th1 responsivity (94 % vs. 33 %, p = 0.0002), repertoire (3.3 vs. 0.3 peptides, p vs. 22.4 SFC/10(6), p non-pCR patients. After controlling for potential confounders, anti-HER2 Th1 responsivity remained independently associated with pathologic response (odds ratio 8.82, p = 0.016). This IFN-γ(+) immune disparity was mediated by anti-HER2 CD4(+)T-bet(+)IFN-γ(+) (i.e., Th1) - not CD4(+)GATA-3(+)IFN-γ(+) (i.e., Th2

B-cell inhibition by cross-linking CD79b is superior to B-cell depletion with anti-CD20 antibodies in treating murine collagen-induced arthritis

Czech Academy of Sciences Publication Activity Database

Bruhl, H.; Cihak, J.; Talke, Y.; Rodriguez-Gomez, M.; Hermann, F.; Goebel, N.; Renner, K.; Plachý, Jiří; Stangassinger, M.; Archemann, S.; Nimmerjahn, F.; Mack, M.

2015-01-01

Roč. 45, č. 3 (2015), s. 705-715 ISSN 0014-2980 Institutional support: RVO:68378050 Keywords : Arthritis * B cells * B-cell depletion * B-cell inhibition * CD79b * Humoral immune response Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.179, year: 2015

Peripheral T-Cell Lymphoma with Aberrant Expression of CD19, CD20, and CD79a: Case Report and Literature Review

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Matnani, Rahul G.; Stewart, Rachel L.; Pulliam, Joseph; Jennings, Chester D.; Kesler, Melissa

2013-01-01

A case of lymphoma of T-cell derivation with aberrant expression of three B-cell lineage markers (CD19, CD20, and CD79a), which was diagnosed on a left axillary excision, is described. Immunohistochemical studies and flow cytometry analysis demonstrated neoplastic cells expressing CD3, CD19, CD20, and CD79a with absence of CD4, CD8, CD10, CD30, CD34, CD56, CD68, TDT, MPO, PAX-5, and surface immunoglobulin. Gene rearrangement studies performed on paraffin blocks demonstrated monoclonal T-cell receptor gamma chain rearrangement with no evidence of clonal heavy chain rearrangement. The neoplastic cells were negative for Epstein-Barr virus (EBV) or Human Herpes Virus 8 (HHV-8). At the time of diagnosis, the PET scan demonstrated hypermetabolic neoplastic cells involving the left axilla, bilateral internal jugular areas, mediastinum, right hilum, bilateral lungs, and spleen. However, bone marrow biopsy performed for hemolytic anemia revealed normocellular bone marrow with trilineage maturation. The patient had no evidence of immunodeficiency or infection with EBV or HHV-8. This is the first reported case of a mature T-cell lymphoma with aberrant expression of three B-cell lineage markers. The current report also highlights the need for molecular gene rearrangement studies to determine the precise lineage of ambiguous neoplastic clones. PMID:24066244

Peripheral T-Cell Lymphoma with Aberrant Expression of CD19, CD20, and CD79a: Case Report and Literature Review

Directory of Open Access Journals (Sweden)

Rahul G. Matnani

2013-01-01

Full Text Available A case of lymphoma of T-cell derivation with aberrant expression of three B-cell lineage markers (CD19, CD20, and CD79a, which was diagnosed on a left axillary excision, is described. Immunohistochemical studies and flow cytometry analysis demonstrated neoplastic cells expressing CD3, CD19, CD20, and CD79a with absence of CD4, CD8, CD10, CD30, CD34, CD56, CD68, TDT, MPO, PAX-5, and surface immunoglobulin. Gene rearrangement studies performed on paraffin blocks demonstrated monoclonal T-cell receptor gamma chain rearrangement with no evidence of clonal heavy chain rearrangement. The neoplastic cells were negative for Epstein-Barr virus (EBV or Human Herpes Virus 8 (HHV-8. At the time of diagnosis, the PET scan demonstrated hypermetabolic neoplastic cells involving the left axilla, bilateral internal jugular areas, mediastinum, right hilum, bilateral lungs, and spleen. However, bone marrow biopsy performed for hemolytic anemia revealed normocellular bone marrow with trilineage maturation. The patient had no evidence of immunodeficiency or infection with EBV or HHV-8. This is the first reported case of a mature T-cell lymphoma with aberrant expression of three B-cell lineage markers. The current report also highlights the need for molecular gene rearrangement studies to determine the precise lineage of ambiguous neoplastic clones.

Study of the CdX-B2X3-X (X=S, Se), CdTe-B-Te systems

International Nuclear Information System (INIS)

Odin, I.N.; Grin'ko, V.V.; Safronov, E.V.; Kozlovskij, V.F.

2001-01-01

Liquidus surfaces of the CdX-B 2 X 3 -X (X=S, Se), CdTe-B-Te systems are plotted for the first time. It is shown that in equilibrium solid solutions on the basis of ternary Cd 2 B 2 X 5 compounds and binary B 2 X 3 , CdX, BS 2 compounds take part with liquid phases. p gen -T and T-x projects of p-T-x phase diagram of B-S (59-100 at. % S), B-Se (59-100 at. % Se), B-Te systems are plotted . B 2 X 3 , BS 2 compounds are formed in that regions of compositions of B-X systems . In the B-Te system compounds are not formed. Ternary compounds are not formed in the CdTe-B-Te system [ru

Decreased memory B cells and increased CD8 memory T cells in blood of breastfed children: the generation R study.

Science.gov (United States)

Jansen, Michelle A E; van den Heuvel, Diana; van Zelm, Menno C; Jaddoe, Vincent W V; Hofman, Albert; de Jongste, Johan C; Hooijkaas, Herbert; Moll, Henriette A

2015-01-01

Breastfeeding provides a protective effect against infectious diseases in infancy. Still, immunological evidence for enhanced adaptive immunity in breastfed children remains inconclusive. To determine whether breastfeeding affects B- and T-cell memory in the first years of life. We performed immunophenotypic analysis on blood samples within a population-based prospective cohort study. Participants included children at 6 months (n=258), 14 months (n=166), 25 months (n=112) and 6 years of age (n=332) with both data on breastfeeding and blood lymphocytes. Total B- and T-cell numbers and their memory subsets were determined with 6-color flow cytometry. Mothers completed questionnaires on breastfeeding when their children were aged 2, 6, and 12 months. Multiple linear regression models with adjustments for potential confounders were performed. Per month continuation of breastfeeding, a 3% (95% CI -6, -1) decrease in CD27+IgM+, a 2% (95 CI % -5, -1) decrease in CD27+IgA+ and a 2% (95% CI -4, -1) decrease in CD27-IgG+ memory B cell numbers were observed at 6 months of age. CD8 T-cell numbers at 6 months of age were 20% (95% CI 3, 37) higher in breastfed than in non-breastfed infants. This was mainly found for central memory CD8 T cells and associated with exposure to breast milk, rather than duration. The same trend was observed at 14 months, but associations disappeared at older ages. Longer breastfeeding is associated with increased CD8 T-cell memory, but not B-cell memory numbers in the first 6 months of life. This transient skewing towards T cell memory might contribute to the protective effect against infectious diseases in infancy.

Decreased memory B cells and increased CD8 memory T cells in blood of breastfed children: the generation R study.

Directory of Open Access Journals (Sweden)

Michelle A E Jansen

Full Text Available Breastfeeding provides a protective effect against infectious diseases in infancy. Still, immunological evidence for enhanced adaptive immunity in breastfed children remains inconclusive.To determine whether breastfeeding affects B- and T-cell memory in the first years of life.We performed immunophenotypic analysis on blood samples within a population-based prospective cohort study. Participants included children at 6 months (n=258, 14 months (n=166, 25 months (n=112 and 6 years of age (n=332 with both data on breastfeeding and blood lymphocytes. Total B- and T-cell numbers and their memory subsets were determined with 6-color flow cytometry. Mothers completed questionnaires on breastfeeding when their children were aged 2, 6, and 12 months. Multiple linear regression models with adjustments for potential confounders were performed.Per month continuation of breastfeeding, a 3% (95% CI -6, -1 decrease in CD27+IgM+, a 2% (95 CI % -5, -1 decrease in CD27+IgA+ and a 2% (95% CI -4, -1 decrease in CD27-IgG+ memory B cell numbers were observed at 6 months of age. CD8 T-cell numbers at 6 months of age were 20% (95% CI 3, 37 higher in breastfed than in non-breastfed infants. This was mainly found for central memory CD8 T cells and associated with exposure to breast milk, rather than duration. The same trend was observed at 14 months, but associations disappeared at older ages.Longer breastfeeding is associated with increased CD8 T-cell memory, but not B-cell memory numbers in the first 6 months of life. This transient skewing towards T cell memory might contribute to the protective effect against infectious diseases in infancy.

Radiolabeling of anti-CD20 with Re-188 for treatment of non-Hodgkin's lymphoma: radiochemical control

International Nuclear Information System (INIS)

Dias, Carla R.; Osso Junior, Joao A.

2009-01-01

The development of tumor-selective radiopharmaceuticals is clinically desirable as a means of detecting or confirming the presence and location of primary and metastatic lesions and monitoring tumor response to (chemo)therapy. In addition, the application of targeted radiotherapeutics provides a unique and effective modality for direct tumor treatment. In this manner the radioimmunotherapy (RIT) uses the targeting features of monoclonal antibody to deliver radiation from an attached radionuclide. Antibody therapy directed against the CD20 antigen on the surface of B-cells is considered one of the first successful target-specific therapies in oncology. The radionuclide rhenium-188 ( 188 Re) is currently produced from the father nuclide tungsten-188 ( 188 W) through a transportable generator system. Because of its easy availability and suitable nuclear properties (EβMAX = 2.1 MeV, t 1/2 = 16.9 h, Eγ = 155 keV), this radionuclide is considered an attractive candidate for application as therapeutic agent and could be conveniently utilized for imaging and dosimetric purposes. The purpose of this work is to show the radiochemical control of the optimized formulation (solution) and lyophilized formulation (kit) of labeled rituximab (anti-CD20) with 188 Re. Rituximab was reduced by incubation with 2-mercaptoethanol at room temperature. The number of resulting free sulfhydryl groups was assayed with Ellman's reagent. Radiochemical purity of 188 Re-rituximab was evaluated using instant thin layer chromatography-silica gel (ITLC-SG). Quality control methods for evaluation of radiochemical purity showed good labeling yield of the antibody. (author)

Biodistribution of Yttrium-90-Labeled Anti-CD45 Antibody in a Nonhuman Primate Model

International Nuclear Information System (INIS)

Nemecek, Eneida; Hamlin, Donald K.; Fisher, Darrell R.; Krohn, Kenneth A.; Pagel, John M.; Applebaum, F. R.; Press, Oliver W.; Matthews, Dana C.

2005-01-01

Radioimmunotherapy may improve the outcome of hematopoietic cell transplantation for hematologic malignancies by delivering targeted radiation to hematopoietic organs while relatively sparing nontarget organs. We evaluated the organ localization of yttrium-90-labeled anti-CD45 (90Y-anti-CD45) antibody in macaques, a model that had previously predicted iodine-131-labeled anti-CD-45 (131I-anti-CD45) antibody biodistribution in humans. Experimental Design: Twelve Macaca nemestrina primates received anti-CD45 antibody labeled with 1 to 2 mCi of 90Y followed by serial blood sampling and marrow and lymph node biopsies, and necropsy. The content of 90Y per gram of tissue was determined by liquid scintillation spectrometry. Time-activity curves were constructed using average isotope concentrations in each tissue at measured time points to yield the fractional residence time and estimate radiation absorbed doses for each organ per unit of administered activity. The biodistribution of 90Y-anti-CD45 antibody was then compared with that previously obtained with 131I-anti-CD45 antibody in macaques. Results: The spleen received 2,120, marrow 1,060, and lymph nodes 315 cGy/mCi of 90Y injected. The liver and lungs were the nontarget organs receiving the highest radiation absorbed doses (440 and 285 cGy/mCi, respectively). Ytrrium-90-labeled anti-CD45 antibody delivered 2.5- and 3.7-fold more radiation to marrow than to liver and lungs, respectively. The ratios previously observed with 131I-antiCD45 antibody were 2.5-and 2.2-fold more radiation to marrow than to liver and lungs, respectively. Conclusions: This study shows that 90Y-anti-CD45 antibody can deliver relatively selective radiation to hematopoietic tissues, with similar ratios of radiation delivered to target versus nontarget organs, as compared with the 131I immunoconjugate in the same animal model

Reactive glia promote development of CD103+ CD69+ CD8+ T-cells through programmed cell death-ligand 1 (PD-L1).

Science.gov (United States)

Prasad, Sujata; Hu, Shuxian; Sheng, Wen S; Chauhan, Priyanka; Lokensgard, James R

2018-06-01

Previous work from our laboratory has demonstrated in vivo persistence of CD103 + CD69 + brain resident memory CD8 + T-cells (bT RM ) following viral infection, and that the PD-1: PD-L1 pathway promotes development of these T RM cells within the brain. Although glial cells express low basal levels of PD-L1, its expression is upregulated upon IFN-γ-treatment, and they have been shown to modulate antiviral T-cell effector responses through the PD-1: PD-L1 pathway. We performed flow cytometric analysis of cells from co-cultures of mixed glia and CD8 + T-cells obtained from wild type mice to investigate the role of glial cells in the development of bT RM . In this study, we show that interactions between reactive glia and anti-CD3 Ab-stimulated CD8 + T-cells promote development of CD103 + CD69 + CD8 + T-cells through engagement of the PD-1: PD-L1 pathway. These studies used co-cultures of primary murine glial cells obtained from WT animals along with CD8 + T-cells obtained from either WT or PD-1 KO mice. We found that αCD3 Ab-stimulated CD8 + T-cells from WT animals increased expression of CD103 and CD69 when co-cultured with primary murine glial cells. In contrast, significantly reduced expression of CD103 and CD69 was observed using CD8 + T-cells from PD-1 KO mice. We also observed that reactive glia promoted high levels of CD127, a marker of memory precursor effector cells (MPEC), on CD69 + CD8 + T-cells, which promotes development of T RM cells. Interestingly, results obtained using T-cells from PD-1 KO animals showed significantly reduced expression of CD127 on CD69 + CD8 + cells. Additionally, blocking of glial PD-L1 resulted in decreased expression of CD103, along with reduced CD127 on CD69 + CD8 + T-cells. Taken together, these results demonstrate a role for activated glia in promoting development of bT RM through the PD-1: PD-L1 pathway. © 2018 The Authors. Immunity, Inflammation and Disease Published by John Wiley & Sons Ltd.

Ectopic expression of anti-HIV-1 shRNAs protects CD8+ T cells modified with CD4ζ CAR from HIV-1 infection and alleviates impairment of cell proliferation

International Nuclear Information System (INIS)

Kamata, Masakazu; Kim, Patrick Y.; Ng, Hwee L.; Ringpis, Gene-Errol E.; Kranz, Emiko; Chan, Joshua; O'Connor, Sean; Yang, Otto O.; Chen, Irvin S.Y.

2015-01-01

Chimeric antigen receptors (CARs) are artificially engineered receptors that confer a desired specificity to immune effector T cells. As an HIV-1-specific CAR, CD4ζ CAR has been extensively tested in vitro as well as in clinical trials. T cells modified with this CAR mediated highly potent anti-HIV-1 activities in vitro and were well-tolerated in vivo, but exerted limited effects on viral load and reservoir size due to poor survival and/or functionality of the transduced cells in patients. We hypothesize that ectopic expression of CD4ζ on CD8 + T cells renders them susceptible to HIV-1 infection, resulting in poor survival of those cells. To test this possibility, highly purified CD8 + T cells were genetically modified with a CD4ζ-encoding lentiviral vector and infected with HIV-1. CD8 + T cells were vulnerable to HIV-1 infection upon expression of CD4ζ as evidenced by elevated levels of p24 Gag in cells and culture supernatants. Concurrently, the number of CD4ζ-modified CD8 + T cells was reduced relative to control cells upon HIV-1 infection. To protect these cells from HIV-1 infection, we co-expressed two anti-HIV-1 shRNAs previously developed by our group together with CD4ζ. This combination vector was able to suppress HIV-1 infection without impairing HIV-1-dependent effector activities of CD4ζ. In addition, the number of CD4ζ-modified CD8 + T cells maintained similar levels to that of the control even under HIV-1 infection. These results suggest that protecting CD4ζ-modified CD8 + T cells from HIV-1 infection is required for prolonged HIV-1-specific immune surveillance. - Highlights: • Ectopic expression of CD4ζ CAR in CD8 + T cells renders them susceptible to HIV-1 infection. • Co-expression of two anti-HIV-1 shRNAs protects CD4ζ CAR-modified CD8 + T cells from HIV-1 infection. • Protecting CD4ζ CAR-modified CD8 + T cells from HIV-1 infection suppresses its cytopathic effect

CD83 Antibody Inhibits Human B Cell Responses to Antigen as well as Dendritic Cell-Mediated CD4 T Cell Responses.

Science.gov (United States)

Wong, Kuan Y; Baron, Rebecca; Seldon, Therese A; Jones, Martina L; Rice, Alison M; Munster, David J

2018-05-15

Anti-CD83 Ab capable of Ab-dependent cellular cytotoxicity can deplete activated CD83 + human dendritic cells, thereby inhibiting CD4 T cell-mediated acute graft-versus-host disease. As CD83 is also expressed on the surface of activated B lymphocytes, we hypothesized that anti-CD83 would also inhibit B cell responses to stimulation. We found that anti-CD83 inhibited total IgM and IgG production in vitro by allostimulated human PBMC. Also, Ag-specific Ab responses to immunization of SCID mice xenografted with human PBMC were inhibited by anti-CD83 treatment. This inhibition occurred without depletion of all human B cells because anti-CD83 lysed activated CD83 + B cells by Ab-dependent cellular cytotoxicity and spared resting (CD83 - ) B cells. In cultured human PBMC, anti-CD83 inhibited tetanus toxoid-stimulated B cell proliferation and concomitant dendritic cell-mediated CD4 T cell proliferation and expression of IFN-γ and IL-17A, with minimal losses of B cells (80% of B cells but had no effect on CD4 T cell proliferation and cytokine expression. By virtue of the ability of anti-CD83 to selectively deplete activated, but not resting, B cells and dendritic cells, with the latter reducing CD4 T cell responses, anti-CD83 may be clinically useful in autoimmunity and transplantation. Advantages might include inhibited expansion of autoantigen- or alloantigen-specific B cells and CD4 T cells, thus preventing further production of pathogenic Abs and inflammatory cytokines while preserving protective memory and regulatory cells. Copyright © 2018 by The American Association of Immunologists, Inc.

Glutamine or whey-protein supplementation on alloxan-induced diabetic rats. Effects on CD4+ and CD8+ lymphocytes Efeitos da oferta de glutamina ou de proteína do soro de leite sobre os linfócitos CD4+ e CD8+ em ratos diabéticos aloxano induzidos

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Renato Motta Neto

2007-06-01

(0,75g/Kg;(G4: PSL, (0,7g/Kg, 2,0ml. Todas as soluções foram administradas por gavagem, diariamente, cada 7:00 h, durante 30 dias. Após esse período, foram coletadas amostradas de sangue arterial para contagem de linfócitos CD4+ e CD8+ por citometria de fluxo. RESULTADOS: A população de linfócitos CD4+ e CD8+ diminuiu significantemente em todos os grupos em comparação aos valores encontrados no grupo G1. A razão CD4+/CD8+ foi significantemente maior (>260% nos ratos tratados com L-Gln que nos ratos tratados com salina (G2. Não se observaram diferenças significantes na população de linfócitos CD4+ e CD8+ entre os grupos G3 e G2. Houve redução significante do número de células CD8+ quando comparado ao número de células CD4+ nos ratos tratados com L-Gln (G3. CONCLUSÃO: A oferta de L-Gln em ratos diabéticos aloxano-induzidos melhora a resposta imunológica à infecção.

A novel antibody-drug conjugate anti-CD19(Fab)-LDM in the treatment of B-cell non-Hodgkin lymphoma xenografts with enhanced anticancer activity.

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Jiang, Linlin; Yang, Ming; Zhang, Xiaoyun; Bao, Shiqi; Ma, Li; Fan, Dongmei; Zhou, Yuan; Xiong, Dongsheng; Zhen, Yongsu

2016-01-01

Rituximab is widely used in clinical setting for the treatment of B malignant lymphoma and has achieved remarkable success. However, in most patients, the disease ultimately relapses and become resistant to rituximab. To overcome the limitation, there is still a need to find novel strategy for improving therapeutic efficacy. To construct genetically engineered antibody anti-CD19(Fab)-LDM, and verify the anticancer activity targeted toward B-lymphoma. The anticancer activity of anti-CD19(Fab)-LDM in vitro and in vivo was examined. In vitro, the binding activity and internalization of anti-CD19(Fab)-LDP were measured. Using comet assay and apoptosis, the cytotoxicity of energized fusion proteins was observed. From in vivo experiments, targeting of therapeutic effect and anticancer efficacy bythe fusion protein was verified. Data showed that anti-CD19(Fab)-LDM does not only binding the cell surface but is also internalized into the cell. The energized fusion proteins anti-CD19(Fab)-LDM can induce DNA damage. Furthermore, significant in vivo therapeutic efficacy was observed. The present study demonstrated that the genetically engineered antibody anti-CD19(Fab)-LDM exhibited enhanced cytotoxicity compared to LDM alone. One of the most powerful advantages of anti-CD19(Fab)-LDM, however, is that it can be internalized within the cells and carry out cytotoxic effects. Therefore, anti-CD19(Fab)-LDM may be as a useful targeted therapy for B-cell lymphoma.

mTOR Complex Signaling through the SEMA4A-Plexin B2 Axis Is Required for Optimal Activation and Differentiation of CD8+ T Cells.

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Ito, Daisuke; Nojima, Satoshi; Nishide, Masayuki; Okuno, Tatsusada; Takamatsu, Hyota; Kang, Sujin; Kimura, Tetsuya; Yoshida, Yuji; Morimoto, Keiko; Maeda, Yohei; Hosokawa, Takashi; Toyofuku, Toshihiko; Ohshima, Jun; Kamimura, Daisuke; Yamamoto, Masahiro; Murakami, Masaaki; Morii, Eiichi; Rakugi, Hiromi; Isaka, Yoshitaka; Kumanogoh, Atsushi

2015-08-01

Mammalian target of rapamycin (mTOR) plays crucial roles in activation and differentiation of diverse types of immune cells. Although several lines of evidence have demonstrated the importance of mTOR-mediated signals in CD4(+) T cell responses, the involvement of mTOR in CD8(+) T cell responses is not fully understood. In this study, we show that a class IV semaphorin, SEMA4A, regulates CD8(+) T cell activation and differentiation through activation of mTOR complex (mTORC) 1. SEMA4A(-/-) CD8(+) T cells exhibited impairments in production of IFN-γ and TNF-α and induction of the effector molecules granzyme B, perforin, and FAS-L. Upon infection with OVA-expressing Listeria monocytogenes, pathogen-specific effector CD8(+) T cell responses were significantly impaired in SEMA4A(-/-) mice. Furthermore, SEMA4A(-/-) CD8(+) T cells exhibited reduced mTORC1 activity and elevated mTORC2 activity, suggesting that SEMA4A is required for optimal activation of mTORC1 in CD8(+) T cells. IFN-γ production and mTORC1 activity in SEMA4A(-/-) CD8(+) T cells were restored by administration of recombinant Sema4A protein. In addition, we show that plexin B2 is a functional receptor of SEMA4A in CD8(+) T cells. Collectively, these results not only demonstrate the role of SEMA4A in CD8(+) T cells, but also reveal a novel link between a semaphorin and mTOR signaling. Copyright © 2015 by The American Association of Immunologists, Inc.

CD137 is induced by the CD40 signal on chronic lymphocytic leukemia B cells and transduces the survival signal via NF-κB activation.

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Yukana Nakaima

Full Text Available CD137 is a member of the tumor necrosis factor receptor family that is expressed on activated T cells. This molecule provides a co-stimulatory signal that enhances the survival, and differentiation of cells, and has a crucial role in the development of CD8 cytotoxic T cells and anti-tumor immunity. Here we report that CD137 expression is also induced on normal or malignant human B cells by CD40 ligation by its ligand CD154. This CD137 induction was more prominent in chronic lymphocytic leukemia (CLL cells than in other types of B cells. CD137 stimulation on B cells by its ligand induced the nuclear translocation of p52 (a non-canonical NF-κB factor. In agreement with this finding, expression of the survival factor BCL-XL was upregulated. Consequently, the CD137 signal augmented the survival of CD154-stimulated CLL B cells in vitro. This unexpected induction of CD137 on B cells by CD40 signal may influence the clinical course of CLL.

Whole-gene analysis of two groups of hepatitis B virus C/D inter-genotype recombinant strains isolated in Tibet, China.

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Tiezhu Liu

Full Text Available Tibet is a highly hepatitis B virus (HBV endemic area. Two types of C/D recombinant HBV are commonly isolated in Tibet and have been previously described. In an effort to better understand the molecular characteristic of these C/D recombinant strains from Tibet, we undertook a multistage random sampling project to collect HBsAg positive samples. Molecular epidemiological and bio-informational technologies were used to analyze the characteristics of the sequences found in this study. There were 60 samples enrolled in the survey, and we obtained 19 whole-genome sequences. 19 samples were all C/D recombinant, and could be divided into two sub-types named C/D1 and C/D2 according to the differences in the location of the recombinant breakpoint. The recombination breakpoint of the 10 strains belonging to the C/D1 sub-type was located at nt750, while the 9 stains belonging to C/D2 had their recombination break point at nt1530. According to whole-genome sequence analysis, the 19 identified strains belong to genotype C, but the nucleotide distance was more than 5% between the 19 strains and sub-genotypes C1 to C15. The distance between C/D1with C2 was 5.8±2.1%, while the distance between C/D2 with C2 was 6.4±2.1%. The parental strain was most likely sub-genotype C2. C/D1 strains were all collected in the middle and northern areas of Tibet including Lhasa, Linzhi and Ali, while C/D2 was predominant in Shannan in southern Tibet. This indicates that the two recombinant genotypes are regionally distributed in Tibet. These results provide important information for the study of special HBV recombination events, gene features, virus evolution, and the control and prevention policy of HBV in Tibet.

TRAF2 regulates peripheral CD8(+) T-cell and NKT-cell homeostasis by modulating sensitivity to IL-15.

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Villanueva, Jeanette E; Malle, Elisabeth K; Gardam, Sandra; Silveira, Pablo A; Zammit, Nathan W; Walters, Stacey N; Brink, Robert; Grey, Shane T

2015-06-01

In this study, a critical and novel role for TNF receptor (TNFR) associated factor 2 (TRAF2) is elucidated for peripheral CD8(+) T-cell and NKT-cell homeostasis. Mice deficient in TRAF2 only in their T cells (TRAF2TKO) show ∼40% reduction in effector memory and ∼50% reduction in naïve CD8(+) T-cell subsets. IL-15-dependent populations were reduced further, as TRAF2TKO mice displayed a marked ∼70% reduction in central memory CD8(+) CD44(hi) CD122(+) T cells and ∼80% decrease in NKT cells. TRAF2TKO CD8(+) CD44(hi) T cells exhibited impaired dose-dependent proliferation to exogenous IL-15. In contrast, TRAF2TKO CD8(+) T cells proliferated normally to anti-CD3 and TRAF2TKO CD8(+) CD44(hi) T cells exhibited normal proliferation to exogenous IL-2. TRAF2TKO CD8(+) T cells expressed normal levels of IL-15-associated receptors and possessed functional IL-15-mediated STAT5 phosphorylation, however TRAF2 deletion caused increased AKT activation. Loss of CD8(+) CD44(hi) CD122(+) and NKT cells was mechanistically linked to an inability to respond to IL-15. The reduced CD8(+) CD44(hi) CD122(+) T-cell and NKT-cell populations in TRAF2TKO mice were rescued in the presence of high dose IL-15 by IL-15/IL-15Rα complex administration. These studies demonstrate a critical role for TRAF2 in the maintenance of peripheral CD8(+) CD44(hi) CD122(+) T-cell and NKT-cell homeostasis by modulating sensitivity to T-cell intrinsic growth factors such as IL-15. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A case for hidden b anti b tetraquarks based on e+e- → b anti b cross sections between √(s) = 10.54 and 11.20 GeV

International Nuclear Information System (INIS)

Ali, Ahmed; Hambrock, Christian; Ahmed, Ishtiaq; Aslam, M. Jamil

2009-11-01

We study the spectroscopy and dominant decays of the bottomonium-like tetraquarks (bound diquarks-antidiquarks), focusing on the lowest lying P-wave [bq][anti b anti q] states Y [bq] (with q=u,d), having J PC =1 -- . To search for them, we analyse the BABAR data obtained during an energy scan of the e + e - →b anti b cross section in the range of √(s)=10.54 to 11.20 GeV. We find that these data are consistent with the presence of an additional b anti b state Y [bq] with a mass of 10.90 GeV and a width of about 30 MeV apart from the Υ(5S) and Υ(6S) resonances. A closeup of the energy region around the Y [bq] -mass may resolve this state in terms of the two mass eigenstates, Y [b,l] and Y [b,h] , with a mass difference, estimated as about 6 MeV. We tentatively identify the state Y [bq] (10900) from the R b -scan with the state Y b (10890) observed by BELLE in the process e + e - →Y b (10890)→Υ(1S,2S)π + π - due to their proximity in masses and decay widths. (orig.)

The experimental study on biodistribution and radioimmunoimaging of 131I labeled anti-lymphoma Fab antibody in nude mice bearing human B cell lymphoma

International Nuclear Information System (INIS)

Yang Xiaochun; Zhang Meihua; Shen Junkang; Shen Yongmei; Shi Yizhen; Liu Zengli

2008-01-01

Objective: Radioimmunoimaging is still an interesting study in the domain of nuclear medicine. The aim of this study was to evaluate the biodistribution and radioimmunoimaging of 131 I-Fab anti- body in nude mice beating human B cell lymphoma. Methods: The immunoreactivity of Fab antibody to Raji cells was analyzed by immunohistochemistry and flow cytometry. Fab antibody and CD20 monoclonal antibody (as control) were labeled with 131 I using Iodogen method. 131 I-Fab antibody or 131 I-CD20 was injected into nude mice bearing B cell lymphoma via tail veins. The biodistribution and radioimmunoimaging results were obtained at 2, 4, 8 and 24 h postinjection, respectively. Results: The results of immunohistochemistry and flow cytometry indicated that both Fab antibody and 131 I-Fab antibody could bind strongly with membrane antigens on Raji cells, and the binding rate reached above 87%. Clear tumor image was obtained at 8 h after injection with 131 I-Fab and elimination was observed at 24 h postinjection. The clear tumor image for 131 I-CD20 antibody was obtained at 24 h post injection. The biodistribution in vivo showed that the percentage activities of injection dose per gram of tumor (% ID/g) of 131 I-Fab group at 2, 4, 8 h postinjection were higher than that of 131 I-CD20 antibody [(1.37±0.28), (1.84±0.13), (2.21±0.15)% ID/g vs (0.33±0.06), (0.62±0.08), (1.46±0.24)% ID/g, respectively; F=52.22, 278.42 and 29.00, all P 131 I-Fad and 131 I-CD20 groups at 2, 4, 8 and 24 h were [(0.22±0.03)-(5.44± 0.31)] vs[(0.04±0.01)-(3.10±0.29)], [(0.43±0.11) - (21.01±3.97)] vs [(0.11±0.05) - (7.99±1.81)], [(1.09±0.07) -(20.28±2.77)] vs [(0.48±0.06) - (23.55±1.69)], [(1.12± 0.02) - (10.29±1.78)] vs [(2.32 ± 0.34) - (33.23±6.83)], respectively. Conclusion: 131 I-Fab anti- body has advantages of small molecular weight, excellent targeting characteristics, early imaging and fast elimination, which indicates the potential application value in diagnosing B cell

Inferring the Impact of Regulatory Mechanisms that Underpin CD8+ T Cell Control of B16 Tumor Growth In vivo Using Mechanistic Models and Simulation.

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Klinke, David J; Wang, Qing

2016-01-01

A major barrier for broadening the efficacy of immunotherapies for cancer is identifying key mechanisms that limit the efficacy of tumor infiltrating lymphocytes. Yet, identifying these mechanisms using human samples and mouse models for cancer remains a challenge. While interactions between cancer and the immune system are dynamic and non-linear, identifying the relative roles that biological components play in regulating anti-tumor immunity commonly relies on human intuition alone, which can be limited by cognitive biases. To assist natural intuition, modeling and simulation play an emerging role in identifying therapeutic mechanisms. To illustrate the approach, we developed a multi-scale mechanistic model to describe the control of tumor growth by a primary response of CD8+ T cells against defined tumor antigens using the B16 C57Bl/6 mouse model for malignant melanoma. The mechanistic model was calibrated to data obtained following adenovirus-based immunization and validated to data obtained following adoptive transfer of transgenic CD8+ T cells. More importantly, we use simulation to test whether the postulated network topology, that is the modeled biological components and their associated interactions, is sufficient to capture the observed anti-tumor immune response. Given the available data, the simulation results also provided a statistical basis for quantifying the relative importance of different mechanisms that underpin CD8+ T cell control of B16F10 growth. By identifying conditions where the postulated network topology is incomplete, we illustrate how this approach can be used as part of an iterative design-build-test cycle to expand the predictive power of the model.

Sustained CD8+ T-cell responses induced after acute parvovirus B19 infection in humans

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Norbeck, Oscar; Isa, Adiba; Pöhlmann, Christoph

2005-01-01

Murine models have suggested that CD8+ T-cell responses peak early in acute viral infections and are not sustained, but no evidence for humans has been available. To address this, we longitudinally analyzed the CD8+ T-cell response to human parvovirus B19 in acutely infected individuals. We...... observed striking CD8+ T-cell responses, which were sustained or even increased over many months after the resolution of acute disease, indicating that CD8+ T cells may play a prominent role in the control of parvovirus B19 and other acute viral infections of humans, including potentially those generated...

Ectopic expression of anti-HIV-1 shRNAs protects CD8{sup +} T cells modified with CD4ζ CAR from HIV-1 infection and alleviates impairment of cell proliferation

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Kamata, Masakazu, E-mail: masa3k@ucla.edu [Division of Hematology-Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Kim, Patrick Y. [Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Ng, Hwee L. [Division of Infectious Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Ringpis, Gene-Errol E.; Kranz, Emiko; Chan, Joshua; O' Connor, Sean [Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Yang, Otto O. [Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Division of Infectious Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); UCLA AIDS Institute, Los Angeles, CA (United States); AIDS Healthcare Foundation, Los Angeles, CA (United States); Chen, Irvin S.Y. [Division of Hematology-Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); UCLA AIDS Institute, Los Angeles, CA (United States)

2015-07-31

Chimeric antigen receptors (CARs) are artificially engineered receptors that confer a desired specificity to immune effector T cells. As an HIV-1-specific CAR, CD4ζ CAR has been extensively tested in vitro as well as in clinical trials. T cells modified with this CAR mediated highly potent anti-HIV-1 activities in vitro and were well-tolerated in vivo, but exerted limited effects on viral load and reservoir size due to poor survival and/or functionality of the transduced cells in patients. We hypothesize that ectopic expression of CD4ζ on CD8{sup +} T cells renders them susceptible to HIV-1 infection, resulting in poor survival of those cells. To test this possibility, highly purified CD8{sup +} T cells were genetically modified with a CD4ζ-encoding lentiviral vector and infected with HIV-1. CD8{sup +} T cells were vulnerable to HIV-1 infection upon expression of CD4ζ as evidenced by elevated levels of p24{sup Gag} in cells and culture supernatants. Concurrently, the number of CD4ζ-modified CD8{sup +} T cells was reduced relative to control cells upon HIV-1 infection. To protect these cells from HIV-1 infection, we co-expressed two anti-HIV-1 shRNAs previously developed by our group together with CD4ζ. This combination vector was able to suppress HIV-1 infection without impairing HIV-1-dependent effector activities of CD4ζ. In addition, the number of CD4ζ-modified CD8{sup +} T cells maintained similar levels to that of the control even under HIV-1 infection. These results suggest that protecting CD4ζ-modified CD8{sup +} T cells from HIV-1 infection is required for prolonged HIV-1-specific immune surveillance. - Highlights: • Ectopic expression of CD4ζ CAR in CD8{sup +} T cells renders them susceptible to HIV-1 infection. • Co-expression of two anti-HIV-1 shRNAs protects CD4ζ CAR-modified CD8{sup +} T cells from HIV-1 infection. • Protecting CD4ζ CAR-modified CD8{sup +} T cells from HIV-1 infection suppresses its cytopathic effect.

Crystal structure and chemical bonding analysis of BaPtCd{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Gulo, Fakhili [Department of Chemical Education, Sriwijaya University, Inderalaya 30662, South Sumatra (Indonesia); Koehler, Juergen [Max Planck Institut fuer Festkoerperforschung, Heisenbergstrasse 1, 70569 Stuttgart (Germany)

2015-03-15

The new ternary intermetallic phase, BaPtCd{sub 2}, was synthesized by solid-state reaction from direct combination of the elements in a stoichiometric mixture. The reaction was done at 850 C for 15 h, followed by an equilibration at 600 C for 4 d. The crystal structure was determined by X-ray diffraction method on a single crystal. BaPtCd{sub 2} is isotypic to MgCuAl{sub 2} and crystallizes in the orthorhombic space group Cmcm [a = 4.467(2), b = 11.143(4), c = 8.240(3) Aa, V = 410.2(3) Aa{sup 3}, and Z = 4]. Barium atoms are linked together forming zigzag chains. Cadmium atoms are bonded to each other forming six-membered rings of platinum centered boat and anti-boat conformations. BaPtCd{sub 2} contains 16 electrons per formula unit and belongs to the electron poorest compounds with MgCuAl{sub 2} type structure. Calculations based on the linear muffin-tin orbitals method in the atomic spheres approximation show that significant bonding states in BaPtCd{sub 2} are unoccupied. (Copyright copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Evaluation of cell cycle changes activated by the administration of "1"7"7Lu-DOTA-antiCD20

International Nuclear Information System (INIS)

Ramos B, J. C.

2016-01-01

In the present project, cytometric evaluation of cell cycle changes induced by the "1"7"7Lu-DOTA-antiCD20 thermostatic radiopharmaceutical was performed, in which a cell culture of Raji cells from Burkitts lymphoma were used, which are CD20+; for flow cytometry different parameters were measured in which the cells were synchronized in G0/G1 and G2/M, to calculate the dose to nucleus that were given to the cells the Monte Carlo method was used at a dose interval from 1 to 5 Gy. The purpose of this work is to be able to observe by flow cytometry the arrest in the cell cycle with a lower dose interval than the one applied in other papers. (Author)

CXCR5+ CD8+ T Cells Indirectly Offer B Cell Help and Are Inversely Correlated with Viral Load in Chronic Hepatitis B Infection.

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Jiang, Hang; Li, Linhai; Han, Jiang; Sun, Zhiwei; Rong, Yihui; Jin, Yun

2017-04-01

Treatment options for chronic hepatitis B (CHB) infection are extremely limited. CXCR5 + CD8 + T cell is a novel cell subtype and could possess strong cytotoxic properties in HIV infection. In this study, we investigated the role of CXCR5 + CD8 + T cells in CHB patients. Compared to healthy individuals, both CHB patients and hepatitis B virus (HBV)-infected hepatocellular carcinoma patients presented significant upregulation of CXCR5 + CD8 + T cells in peripheral blood, in which CXCR5 + CD8 + T cells were negatively correlated with the frequency of CXCR5 + CD4 + T cells in CHB patients. After PMA+ionomycin stimulation, CXCR5 + CD8 + T cells from CHB patients presented significantly higher transcription level of interferon gamma (IFN-γ), interleukin 10 (IL-10), and IL-21, as well as higher IL-10 and IL-21 protein secretion, than CXCR5 - CD8 + T cells. Unlike CXCR5 + CD4 + T cells, when incubated with naive CD19 + CD27 - B cells, CXCR5 + CD8 + T cells alone did not upregulate IgM, IgG, and IgA secretion. However, addition of CXCR5 + CD8 + T cells in B cell-CXCR5 + CD4 + T cell coculture significantly increased the levels of secreted IgG and IgA, demonstrating that CXCR5 + CD8 + T cell could indirectly offer B cell help. Furthermore, high frequencies of CXCR5 + CD8 + T cells tended to associate with low HBV DNA load, and the frequency of CXCR5 + CD8 + T cells was negatively correlated with alanine aminotransferase (ALT) level. Together, these results suggested that CXCR5 + CD8 + T cells were involved in the antiviral immune responses in CHB and could potentially serve as a therapeutic candidate.

The gene expression profile of CD11c+ CD8α- dendritic cells in the pre-diabetic pancreas of the NOD mouse.

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Wouter Beumer

Full Text Available Two major dendritic cell (DC subsets have been described in the pancreas of mice: The CD11c+ CD8α- DCs (strong CD4+ T cell proliferation inducers and the CD8α+ CD103+ DCs (T cell apoptosis inducers. Here we analyzed the larger subset of CD11c+ CD8α- DCs isolated from the pancreas of pre-diabetic NOD mice for genome-wide gene expression (validated by Q-PCR to elucidate abnormalities in underlying gene expression networks. CD11c+ CD8α- DCs were isolated from 5 week old NOD and control C57BL/6 pancreas. The steady state pancreatic NOD CD11c+ CD8α- DCs showed a reduced expression of several gene networks important for the prime functions of these cells, i.e. for cell renewal, immune tolerance induction, migration and for the provision of growth factors including those for beta cell regeneration. A functional in vivo BrdU incorporation test showed the reduced proliferation of steady state pancreatic DC. The reduced expression of tolerance induction genes (CD200R, CCR5 and CD24 was supported on the protein level by flow cytometry. Also previously published functional tests on maturation, immune stimulation and migration confirm the molecular deficits of NOD steady state DC. Despite these deficiencies NOD pancreas CD11c+ CD8α- DCs showed a hyperreactivity to LPS, which resulted in an enhanced pro-inflammatory state characterized by a gene profile of an enhanced expression of a number of classical inflammatory cytokines. The enhanced up-regulation of inflammatory genes was supported by the in vitro cytokine production profile of the DCs. In conclusion, our data show that NOD pancreatic CD11c+ CD8α- DCs show various deficiencies in steady state, while hyperreactive when encountering a danger signal such as LPS.

Anti-CD40-mediated cancer immunotherapy

DEFF Research Database (Denmark)

Hassan, Sufia Butt; Sørensen, Jesper Freddie; Olsen, Barbara Nicola

2014-01-01

activation and thus enhancement of immune responses. Treatment with anti-CD40 monoclonal antibodies has been exploited in several cancer immunotherapy studies in mice and led to the development of anti-CD40 antibodies for clinical use. Here, Dacetuzumab and Lucatumumab are in the most advanced stage...... with other cancer immunotherapies, in particular interleukin (IL)-2. An in-depth analysis of this immunotherapy is provided elsewhere. In the present review, we provide an update of the most recent clinical trials with anti-CD40 antibodies. We present and discuss recent and ongoing clinical trials...... in this field, including clinical studies which combine anti-CD40 treatment with other cancer-treatments, such as Rituximab and Tremelimumab....

Benefit from B-lymphocyte depletion using the anti-CD20 antibody rituximab in chronic fatigue syndrome. A double-blind and placebo-controlled study.

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Øystein Fluge

Full Text Available Chronic fatigue syndrome (CFS is a disease of unknown aetiology. Major CFS symptom relief during cancer chemotherapy in a patient with synchronous CFS and lymphoma spurred a pilot study of B-lymphocyte depletion using the anti-CD20 antibody Rituximab, which demonstrated significant clinical response in three CFS patients.In this double-blind, placebo-controlled phase II study (NCT00848692, 30 CFS patients were randomised to either Rituximab 500 mg/m(2 or saline, given twice two weeks apart, with follow-up for 12 months. Xenotropic murine leukemia virus-related virus (XMRV was not detected in any of the patients. The responses generally affected all CFS symptoms. Major or moderate overall response, defined as lasting improvements in self-reported Fatigue score during follow-up, was seen in 10 out of 15 patients (67% in the Rituximab group and in two out of 15 patients (13% in the Placebo group (p = 0.003. Mean response duration within the follow-up period for the 10 responders to Rituximab was 25 weeks (range 8-44. Four Rituximab patients had clinical response durations past the study period. General linear models for repeated measures of Fatigue scores during follow-up showed a significant interaction between time and intervention group (p = 0.018 for self-reported, and p = 0.024 for physician-assessed, with differences between the Rituximab and Placebo groups between 6-10 months after intervention. The primary end-point, defined as effect on self-reported Fatigue score 3 months after intervention, was negative. There were no serious adverse events. Two patients in the Rituximab group with pre-existing psoriasis experienced moderate psoriasis worsening.The delayed responses starting from 2-7 months after Rituximab treatment, in spite of rapid B-cell depletion, suggests that CFS is an autoimmune disease and may be consistent with the gradual elimination of autoantibodies preceding clinical responses. The present findings will impact

Effect of UGT2B7*2 and CYP2C8*4 polymorphisms on diclofenac metabolism.

Science.gov (United States)

Lazarska, Katarzyna E; Dekker, Stefan J; Vermeulen, Nico P E; Commandeur, Jan N M

2018-03-01

The use of diclofenac is associated with rare but severe drug-induced liver injury (DILI) in a very small number of patients. The factors which predispose susceptible patients to hepatotoxicity of diclofenac are still incompletely understood. Formation of protein-reactive metabolites by UDP-glucuronosyl transferases and cytochromes P450 is commonly considered to play an important role, as indicated by the detection of covalent protein adducts and antibodies in the serum of patients suffering from diclofenac-induced liver injury. Since no associations have been found with HLA-alleles, polymorphisms of genes encoding for proteins involved in the disposition of diclofenac may be important. Previous association studies showed that possession of the UGT2B7*2 and CYP2C8*4 alleles is more common in cases of diclofenac-induced DILI. In the present study, the metabolism of diclofenac by UGT2B7*2 and CYP2C8*4 was compared with their corresponding wild-type enzymes. Enzyme kinetic analysis revealed that recombinant UGT2B7*2 showed an almost 6-fold lower intrinsic clearance of diclofenac glucuronidation compared to UGT2B7*1. The mutant CYP2C8*4 showed approximately 35% reduced activity in the 4'-hydroxylation of diclofenac acyl glucuronide. Therefore, a decreased hepatic exposure to diclofenac acyl glucuronide is expected in patients with the UGT2B7*2 genotype. The increased risk for hepatotoxicity, therefore, might be the result from a shift to oxidative bioactivation to cytotoxic quinoneimines. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

CD59 Underlines the Antiatherosclerotic Effects of C-Phycocyanin on Mice

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Bing Li

2013-01-01

Full Text Available The effects of C-phycocyanin (C-PC on atherosclerosis and the regulatory effects of CD59 gene on anti-atherosclerotic roles of C-PC were investigated. Apolipoprotein E knockout (ApoE(−/− mice were randomly divided into four groups: control group, C-PC treatment group, CD59 transfection group and C-PC+CD59 synergy group. The mice were fed with high-fat-diet and treated with drug intervention at the same time. Results showed the atherosclerotic mouse model was successfully established. CD59 was over-expressed in blood and tissue cells. Single CD59 or C-PC could reduce blood lipid levels and promote the expression of anti-apoptotic Bcl-2 but inhibit pro-apoptotic Fas proteins in endothelial cells. The expression levels of cell cycle protein D1 (Cyclin D1 and mRNA levels of cyclin dependent protein kinase 4 (CDK4 in smooth muscle cells were restrained by CD59 and C-PC. CD59 or C-PC alone could inhibit the formation of atherosclerotic plaque by suppressing MMP-2 protein expression. In addition, C-PC could promote CD59 expression. So both CD59 and C-PC could inhibit the progress of atherosclerosis, and the anti-atherosclerotic effects of C-PC might be fulfilled by promoting CD59 expression, preventing smooth muscle cell proliferation and the apoptosis of endothelial cells, reducing blood fat levels, and at last inhibiting the development of atherosclerosis.

In ovo injection of anti-chicken CD25 monoclonal antibodies depletes CD4+CD25+ T cells in chickens.

Science.gov (United States)

Shanmugasundaram, Revathi; Selvaraj, Ramesh K

2013-01-01

The CD4(+)CD25(+) cells have T regulatory cell properties in chickens. This study investigated the effect of in ovo injection of anti-chicken CD25 monoclonal antibodies (0.5 mg/egg) on CD4(+)CD25(+) cell depletion and on amounts of interleukin-2 mRNA and interferon-γ mRNA in CD4(+)CD25(-) cells posthatch. Anti-chicken CD25 or PBS (control) was injected into 16-d-old embryos. Chicks hatched from eggs injected with anti-chicken CD25 antibodies had a lower CD4(+)CD25(+) cell percentage in the blood until 25 d posthatch. The anti-chicken CD25 antibody injection nearly depleted CD4(+)CD25(+) cells in the blood until 16 d posthatch. At 30 d posthatch, the CD4(+)CD25(+) cell percentage in the anti-CD25-antibody-injected group was comparable with the percentage in the control group. At 16 d posthatch, the anti-chicken CD25 antibody injection decreased CD4(+)CD25(+) cell percentages in the thymus, spleen, and cecal tonsils. Chickens hatched from anti-CD25-antibody-injected eggs had approximately 25% of CD4(+)CD25(+) cells in the cecal tonsils and thymus compared with those in the cecal tonsils and thymus of the control group. The CD4(+)CD25(-) cells from the spleen and cecal tonsils of chicks hatched from anti-chicken-CD25-injected eggs had higher amounts of interferon-γ and interleukin-2 mRNA than CD4(+)CD25(-) cells from the control group. It could be concluded that injecting anti-chicken CD25 antibodies in ovo at 16 d of incubation nearly depleted the CD4(+)CD25(+) cells until 25 d posthatch.

2,3,7,8-Tetrachlorodibenzo-p-dioxin-mediated disruption of the CD40 ligand-induced activation of primary human B cells

International Nuclear Information System (INIS)

Lu Haitian; Crawford, Robert B.; Kaplan, Barbara L.F.; Kaminski, Norbert E.

2011-01-01

Suppression of the primary antibody response is particularly sensitive to suppression by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in mice; however, surprisingly little is known concerning the effects of TCDD on humoral immunity or B cell function in humans. Results from a limited number of previous studies, primarily employing in vitro activation models, suggested that human B cell effector function is suppressed by TCDD. The present study sought to extend these findings by investigating, in primary human B cells, the effects of TCDD on several critical stages leading to antibody secretion including activation and plasmacytic differentiation using an in vitro CD40 ligand activation model. These studies revealed important differences in the response of human and mouse B cells to TCDD, the most striking being altered expression of plasmacytic differentiation regulators, B lymphocyte-induced maturation protein 1 and paired box protein 5, in mouse but not human B cells. The activation of human B cells was profoundly impaired by TCDD, as evidenced by decreased expression of activation markers CD80, CD86, and CD69. The impaired activation correlated with decreased cell viability, which prevented the progression of human B cells toward plasmacytic differentiation. TCDD treatment also attenuated the early activation of mitogen-activated protein kinases (MAPK) and Akt signaling in human B cells. Collectively, the present study provided experimental evidence for novel mechanisms by which TCDD impairs the effector function of primary human B cells. - Highlights: → In this study primary human and mouse B cell toxicity to TCDD was compared. → TCDD altered the expression of Blimp-1 and Pax5 in mouse but not human B cells. → TCDD markedly suppressed human B cell activation as characterized by CD80, CD86 and CD69 expression. → TCDD inhibited ERK, p38, and Akt phosphorylation in human B cells.

Ascites as the initial characteristic manifestation in a patient with primary gastric CD8-positive diffuse large B-cell lymphoma.

Science.gov (United States)

Zhao, K-X; Dai, G-Z; Zhu, J-F

2016-05-01

Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoid malignancy and the most common type of non-Hodgkin's lymphomas, the stomach is the most common extranodal site. Gastric DLBCL is often characterized by epigastric pain and vomiting. We report a case of a 78-year-old female patient with gastric diffuse large B-cell lymphoma (DLBCL) with high CD8 level which was initially manifested with ascites of unknown origin. The patient was admitted with a chief complaint of abdominal distension and scanty urine over the last twenty days, while without anorexia and fatigue until 15 March. She had no history of viral hepatitis, tuberculosis, schistosomiasis. Laboratory data revealed normal aminotransferases and bilirubin levels, but serum lactate dehydrogenase, CA125, ascitic fluid lactate dehydrogenase, ascitic fluid lymphocytes increased. The ascitic fluid was yellow-colored with 98.5% lymphocytes. Stool occult blood test was positive. Upper gastrointestinal endoscopy performed a few days later revealed multiple gastric crateriform ulcers, and Helicobacter pylori was detected in the biopsy specimen. Peripheral blood CD8+ was increased by 51%. Pathology test showed lymphocytes with atypical hyperplasia, and immunohistochemistry test resulted CD20+, CD10-, CD79α+, κ+, bcl-6+, Ki-67+ (approximately 95%), λ-, bcl-2-, CD3-, CD43-. Immunoglobulin gene (Ig) clonal rearrangement showed IgH: FR1 (+), FR2 (+), FR3(-), Igk: VJ(+), Vkde (+) in lymphoma tissue. The features of histopathology and immunohistochemistry of the tissue confirmed diffuse large B-cell lymphoma (DLBL). The patient received an uncompleted CHOP program combined with H. pylori eradication. However, the patient deceased due to disease development sixteen days later after the diagnosis.

Foothills Parkway Section 8B Final Environmental Report, Volume 2, Appendices A-C

Energy Technology Data Exchange (ETDEWEB)

Blasing, T.J.; Cada, G.F.; Carer, M.; Chin, S.M.; Dickerman, J.A.; Etnier, D.A.; Gibson, R.; Harvey, M.; Hatcher, B.; Lietzske, D.; Mann, L.K.; Mulholland, P.J.; Petrich, C.H.; Pounds, L.; Ranney, J.; Reed, R.M.; Ryan, P.F.; Schweitzer, M.; Smith, D.; Thomason, P.; Wade, M.C.

1999-07-01

In 1994, Oak Ridge National Laboratory (ORNL) was tasked by the National Park Service (NPS) to prepare an Environmental Report (ER) for Section 8B of the Foothills Parkway in the Great Smoky Mountains National Park (GSMNP). Section 8B represents 27.7 km (14.2 miles) of a total of 115 km (72 miles) of the planned Foothills Parkway and would connect the Cosby community on the east to the incorporated town of Pittman Center to the west. The major deliverables for the project are listed. From August 1995 through October 1996, NW, GSMNP, and ORNL staff interacted with Federal Highway Administration staff to develop a conceptual design plan for Section 8B with the intent of protecting critical resources identified during the ER process to the extent possible. In addition, ORNL arranged for bioengineering experts to discuss techniques that might be employed on Section 8B with NPS, GSMNP, and ORNL staff during September 1996. For the purposes of this EN there are two basic alternatives under consideration: (1) a build alternative and (2) a no-build alternative. Within the build alternative are a number of options including constructing Section 8B with no interchanges, constricting Section 8B with an interchange at SR 416 or U.S. 321, constructing Section 8B with a spur road on Webb Mountain, and considering operation of Section 8B both before and after the operation of Section 8C. The no-build alternative is considered the no-action alternative and is not to construct Section 8B. This volume of the ER, which consists of Appendices A, B, and C, assesses the potential geologic impacts of the proposed Section 8B construction, presents the results of the Section 8B soil survey, and describes the water quality studies and analyses performed for the ER. The following summary sections provide information for geology, soils, and water quality.

C5a receptor (CD88) blockade protects against MPO-ANCA GN.

Science.gov (United States)

Xiao, Hong; Dairaghi, Daniel J; Powers, Jay P; Ertl, Linda S; Baumgart, Trageen; Wang, Yu; Seitz, Lisa C; Penfold, Mark E T; Gan, Lin; Hu, Peiqi; Lu, Bao; Gerard, Norma P; Gerard, Craig; Schall, Thomas J; Jaen, Juan C; Falk, Ronald J; Jennette, J Charles

2014-02-01

Necrotizing and crescentic GN (NCGN) with a paucity of glomerular immunoglobulin deposits is associated with ANCA. The most common ANCA target antigens are myeloperoxidase (MPO) and proteinase 3. In a manner that requires activation of the alternative complement pathway, passive transfer of antibodies to mouse MPO (anti-MPO) induces a mouse model of ANCA NCGN that closely mimics human disease. Here, we confirm the importance of C5aR/CD88 in the mediation of anti-MPO-induced NCGN and report that C6 is not required. We further demonstrate that deficiency of C5a-like receptor (C5L2) has the reverse effect of C5aR/CD88 deficiency and results in more severe disease, indicating that C5aR/CD88 engagement enhances inflammation and C5L2 engagement suppresses inflammation. Oral administration of CCX168, a small molecule antagonist of human C5aR/CD88, ameliorated anti-MPO-induced NCGN in mice expressing human C5aR/CD88. These observations suggest that blockade of C5aR/CD88 might have therapeutic benefit in patients with ANCA-associated vasculitis and GN.

CD4+CD25+ regulatory T cells control CD8+ T-cell effector differentiation by modulating IL-2 homeostasis

Science.gov (United States)

McNally, Alice; Hill, Geoffrey R.; Sparwasser, Tim; Thomas, Ranjeny; Steptoe, Raymond J.

2011-01-01

CD4+CD25+ regulatory T cells (Treg) play a crucial role in the regulation of immune responses. Although many mechanisms of Treg suppression in vitro have been described, the mechanisms by which Treg modulate CD8+ T cell differentiation and effector function in vivo are more poorly defined. It has been proposed, in many instances, that modulation of cytokine homeostasis could be an important mechanism by which Treg regulate adaptive immunity; however, direct experimental evidence is sparse. Here we demonstrate that CD4+CD25+ Treg, by critically regulating IL-2 homeostasis, modulate CD8+ T-cell effector differentiation. Expansion and effector differentiation of CD8+ T cells is promoted by autocrine IL-2 but, by competing for IL-2, Treg limit CD8+ effector differentiation. Furthermore, a regulatory loop exists between Treg and CD8+ effector T cells, where IL-2 produced during CD8+ T-cell effector differentiation promotes Treg expansion. PMID:21502514

Mouse CD23 regulates monocyte activation through an interaction with the adhesion molecule CD11b/CD18.

Science.gov (United States)

Lecoanet-Henchoz, S; Plater-Zyberk, C; Graber, P; Gretener, D; Aubry, J P; Conrad, D H; Bonnefoy, J Y

1997-09-01

CD23 is expressed on a variety of hemopoietic cells. Recently, we have reported that blocking CD23 interactions in a murine model of arthritis resulted in a marked improvement of disease severity. Here, we demonstrate that CD11b, the alpha chain of the beta 2 integrin adhesion molecule complex CD11b/CD18 expressed on monocytes interacts with CD23. Using a recombinant fusion protein (ZZ-CD23), murine CD23 was shown to bind to peritoneal macrophages and peripheral blood cells isolated from mice as well as the murine macrophage cell line, RAW. The interactions between mouse ZZ-CD23 and CD11b/CD18-expressing cells were significantly inhibited by anti-CD11b monoclonal antibodies. A functional consequence was then demonstrated by inducing an up-regulation of interleukin-6 (IL-6) production following ZZ-CD23 incubation with monocytes. The addition of Fab fragments generated from the monoclonal antibody CD11b impaired this cytokine production by 50%. Interestingly, a positive autocrine loop was identified as IL-6 was shown to increase CD23 binding to macrophages. These results demonstrate that similar to findings using human cells, murine CD23 binds to the surface adhesion molecule, CD11b, and these interactions regulate biological activities of murine myeloid cells.

Activation of human CD141+ and CD1c+ dendritic cells in vivo with combined TLR3 and TLR7/8 ligation.

Science.gov (United States)

Pearson, Frances E; Chang, Karshing; Minoda, Yoshihito; Rojas, Ingrid M Leal; Haigh, Oscar L; Daraj, Ghazal; Tullett, Kirsteen M; Radford, Kristen J

2018-04-01

Mice reconstituted with human hematopoietic stem cells are valuable models to study aspects of the human immune system in vivo. We describe a humanized mouse model (hu mice) in which fully functional human CD141 + and CD1c + myeloid and CD123 + plasmacytoid dendritic cells (DC) develop from human cord blood CD34 + cells in immunodeficient mice. CD141 + DC are the human equivalents of murine CD8 + /CD103 + DC which are essential for the induction of tumor-inhibitory cytotoxic T lymphocyte responses, making them attractive targets to exploit for the development of new cancer immunotherapies. We used CD34 + -engrafted NSG-A2 mice to investigate activation of DC subsets by synthetic dsRNA or ssRNA analogs polyinosinic-polycytidylic acid/poly I:C and Resiquimod/R848, agonists for TLR3 and TLR8, respectively, both of which are expressed by CD141 + DC. Injection of hu mice with these agonists resulted in upregulation of costimulatory molecules CD80, CD83 and CD86 by CD141 + and CD1c + DC alike, and their combination further enhanced expression of these molecules by both subsets. When combined, poly I:C and R848 enhanced serum levels of key cytokines associated with cross-presentation and the induction of cytotoxic T lymphocyte responses including IFN-α, IFN-β, IL-12 and CXCL10. These data advocate a combination of poly I:C and R848 TLR agonists as means of activating human DC for immunotherapy. © 2018 Australasian Society for Immunology Inc.

Investigation of the decays anti B0 → D*+l-anti ν and anti B → D**l-anti ν

International Nuclear Information System (INIS)

Albrecht, H.; Ehrlichmann, H.; Hamacher, T.; Hofmann, R.P.; Kirchhoff, T.; Nau, A.; Nowak, S.; Schroeder, H.; Schulz, H.D.; Walter, M.; Wurth, R.; Appuhn, R.D.; Hast, C.; Kolanoski, H.; Lange, A.; Lindner, A.; Mankel, R.; Schieber, M.; Siegmund, T.; Spaan, B.; Thurn, H.; Toepfer, D.; Walther, A.; Wegener, D.; Britton, D.I.; Charlesworth, C.E.K.; Edwards, K.W.; Hyatt, E.R.F.; Kapitza, H.; Krieger, P.; MacFarlane, D.B.; Patel, P.M.; Prentice, J.D.; Saull, P.R.B.; Tzamariudaki, K.; Van de Water, R.G.; Yoon, T.S.; Ressing, D.; Schmidtler, M.; Schneider, M.; Schubert, K.R.; Strahl, K.; Waldi, R.; Weseler, S.

1993-01-01

Exclusive semileptonic B decays with a D *+ meson in the final state have been studied using the ARGUS detector at the DORIS II storage ring. The branching ratio for the decay anti B 0 →D *+ l - anti ν, where l - is either e - or μ - , has been measured to be (5.2±0.5±0.6)%. A significant rate for the decay anti B→D ** l - anti ν has been observed. From an angular analysis of the cascade anti B 0 →D *+ (→D 0 π + )l - anti ν the forward-backward asymmetry A FB and the D *+ polarization parameter α have been determined to be A FB =0.20±0.08±0.06 and α=1.1±0.4±0.2. (orig.)

Viscoelastic wormlike micelles formed by ionic liquid-type surfactant [C16imC8]Br towards template-assisted synthesis of CdS quantum dots.

Science.gov (United States)

Hu, Yimin; Han, Jie; Ge, Lingling; Guo, Rong

2018-01-31

In this paper, viscoelastic wormlike micelles consisting of cationic liquid-type surfactant, 1-hexadecyl-3-octyl imidazolium bromide ([C 16 imC 8 ]Br), water and different additives were utilized for the synthesis of CdS quantum dots. First, the influence of different additives, such as [Cd(NH 3 ) 6 ]Cl 2 and ethanethioamid (precursors for the synthesis of CdS quantum dots), and temperature on the viscoelasticity of the [C 16 imC 8 ]Br aqueous solution was studied by dynamic and steady rheology. Furthermore, the synthesized CdS quantum dots and their photoluminescence properties were characterized by transmission electron microscopy (TEM), UV-Vis absorption spectroscopy, X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDX). In the end, the mechanism for the synthesis of CdS quantum dots in [C 16 imC 8 ]Br wormlike micelles is proposed.

Cross-protective immunity to Leishmania amazonensis is mediated by CD4+ and CD8+-epitopes of Leishmania donovani Nucleoside Hydrolase terminal domains

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Dirlei eNico

2014-05-01

Full Text Available The Nucleoside hydrolase of Leishmania donovani (NH36 is a phylogenetic marker of high homology among Leishmania parasites. In mice and dog vaccination NH36 induces a CD4+ T cell-driven protective response against Leishmania chagasi infection directed against its C-terminal domain (F3. The C-terminal and N-terminal domain vaccines also decreased the footpad lesion caused by Leishmania amazonensis. We studied the basis of the crossed immune response using recombinant generated peptides covering the whole NH36 sequence and saponin for mice prophylaxis against L. amazonensis. The F1 (amino acids 1-103 and F3 peptide (amino acids 199-314 vaccines enhanced the IgG and IgG2a anti-NH36 antibodies to similar levels. The F3 vaccine induced the strongest DTH response, the highest proportions of NH36-specific CD4+ and CD8+ T cells after challenge and the highest expression of IFN-γ and TNF-α. The F1 vaccine, on the other hand, induced a weaker but significant DTH response and a mild enhancement of IFN-γ and TNF-α levels. The in vivo depletion with anti-CD4 or CD8 monoclonal antibodies disclosed that cross-protection against L. amazonensis infection was mediated by a CD4+ T cell response directed against the C-terminal domain (75% of reduction of the size of footpad lesion followed by a CD8+ T cell response against the N-terminal domain of NH36 (57% of reduction of footpad lesions. Both vaccines were capable of inducing long-term cross-immunity. The amino acid sequence of NH36 showed 93% identity to the sequence of the NH A34480 of L. amazonensis which also showed the presence of completely conserved predicted epitopes for CD4+ and CD8+ T cells in F1 domain, and of CD4+ epitopes differing in a single amino acid, in F1 and F3 domains. The identification of the C-terminal and N-terminal domains as the targets of the immune response to NH36 in the model of L. amazonesis infection represents a basis for the rationale development of a bivalent vaccine

Measurement of basophil-activating capacity of grass pollen allergens, allergoids and hypoallergenic recombinant derivatives by flow cytometry using anti-CD203c.

Science.gov (United States)

Kahlert, H; Cromwell, O; Fiebig, H

2003-09-01

The assessment of the basophil-activating potential is an important aspect in the development of improved preparations for specific immunotherapy. The aim of the study was to evaluate the suitability of CD203c expression as a measure of basophil activation to compare allergoids with original allergen extracts, and recombinant hypoallergenic allergen derivatives with recombinant wild-type and natural allergens. Heparinized whole blood samples from grass pollen allergic subjects were stimulated with grass pollen allergens and allergen derivatives followed by labelling of the basophils with PE-conjugated anti-CD203c. After lysis of the erythrocytes and fixation, the basophils were detected by flow cytometry. In some experiments, histamine release was determined simultaneously. Grass pollen allergoids revealed a 10-10 000-fold reduction of basophil-activating capacity measured by CD203c expression. The deletion mutant DM4 of rPhl p 5b showed stronger hypoallergenic characteristics in a range of 50-10 000-fold reduction, whereas a combination mutant of rPhl p 5b and Phl p 6 revealed less hypoallergenic features. Histamine release experiments led to a similar outcome as CD203c measurement. The measurement of CD203c expression on basophils by flow cytometry provides a rapid and sensitive method for the estimation of the allergic or hypoallergenic features of allergen preparations. The results demonstrated the hypoallergenicity of grass pollen allergoids and of the rPhl p 5b variant DM4, which may be a candidate in future preparations for specific immunotherapy.

Anti pp elastic scattering at 30 GeV/c incident momentum in the momentum transfer range 0. 5<-t<5. 8(GeV/c)/sup 2/

Energy Technology Data Exchange (ETDEWEB)

Asa' d, Z.; Coupland, M.; Davis, D.G.; Duff, B.G.; Fearnley, T.; Heymann, F.F.; Imrie, D.C.; Lush, G.J.; Phillips, M. (University Coll., London (UK)); Baglin, A.

1983-10-27

The anti pp elastic differential cross section at 30 GeV/c incident momentum has been measured in a two-arm spectrometer experiment (WA7) at the CERN SPS. The vertical stroketvertical stroke-range covered extends from 0.5 to 5.8 (GeV/c)/sup 2/. A pronounced dip-bump structure is observed, with a sharp minimum around vertical stroketvertical strokeapprox.=1.7 (GeV/c)/sup 2/. The results are compared with existing anti pp data at lower energies and with our earlier anti pp data at 50 GeV/c. A number of model predictions are discussed. We also compare the anti pp 30 GeV/c differential cross section with that of pp at the same momentum. Finally, the energy dependence of the anti pp fixed-vertical stroketvertical stroke differential cross section in the incident momentum range 3.6 to 50 GeV/c is presented.

Identification and HLA-tetramer-validation of human CD4+ and CD8+ T cell responses against HCMV proteins IE1 and IE2.

Science.gov (United States)

Braendstrup, Peter; Mortensen, Bo Kok; Justesen, Sune; Osterby, Thomas; Rasmussen, Michael; Hansen, Andreas Martin; Christiansen, Claus Bohn; Hansen, Morten Bagge; Nielsen, Morten; Vindeløv, Lars; Buus, Søren; Stryhn, Anette

2014-01-01

Human cytomegalovirus (HCMV) is an important human pathogen. It is a leading cause of congenital infection and a leading infectious threat to recipients of solid organ transplants as well as of allogeneic hematopoietic cell transplants. Moreover, it has recently been suggested that HCMV may promote tumor development. Both CD4+ and CD8+ T cell responses are important for long-term control of the virus, and adoptive transfer of HCMV-specific T cells has led to protection from reactivation and HCMV disease. Identification of HCMV-specific T cell epitopes has primarily focused on CD8+ T cell responses against the pp65 phosphoprotein. In this study, we have focused on CD4+ and CD8+ T cell responses against the immediate early 1 and 2 proteins (IE1 and IE2). Using overlapping peptides spanning the entire IE1 and IE2 sequences, peripheral blood mononuclear cells from 16 healthy, HLA-typed, donors were screened by ex vivo IFN-γ ELISpot and in vitro intracellular cytokine secretion assays. The specificities of CD4+ and CD8+ T cell responses were identified and validated by HLA class II and I tetramers, respectively. Eighty-one CD4+ and 44 CD8+ T cell responses were identified representing at least seven different CD4 epitopes and 14 CD8 epitopes restricted by seven and 11 different HLA class II and I molecules, respectively, in total covering 91 and 98% of the Caucasian population, respectively. Presented in the context of several different HLA class II molecules, two epitope areas in IE1 and IE2 were recognized in about half of the analyzed donors. These data may be used to design a versatile anti-HCMV vaccine and/or immunotherapy strategy.

Identification and HLA-tetramer-validation of human CD4+ and CD8+ T cell responses against HCMV proteins IE1 and IE2.

Directory of Open Access Journals (Sweden)

Peter Braendstrup

Full Text Available Human cytomegalovirus (HCMV is an important human pathogen. It is a leading cause of congenital infection and a leading infectious threat to recipients of solid organ transplants as well as of allogeneic hematopoietic cell transplants. Moreover, it has recently been suggested that HCMV may promote tumor development. Both CD4+ and CD8+ T cell responses are important for long-term control of the virus, and adoptive transfer of HCMV-specific T cells has led to protection from reactivation and HCMV disease. Identification of HCMV-specific T cell epitopes has primarily focused on CD8+ T cell responses against the pp65 phosphoprotein. In this study, we have focused on CD4+ and CD8+ T cell responses against the immediate early 1 and 2 proteins (IE1 and IE2. Using overlapping peptides spanning the entire IE1 and IE2 sequences, peripheral blood mononuclear cells from 16 healthy, HLA-typed, donors were screened by ex vivo IFN-γ ELISpot and in vitro intracellular cytokine secretion assays. The specificities of CD4+ and CD8+ T cell responses were identified and validated by HLA class II and I tetramers, respectively. Eighty-one CD4+ and 44 CD8+ T cell responses were identified representing at least seven different CD4 epitopes and 14 CD8 epitopes restricted by seven and 11 different HLA class II and I molecules, respectively, in total covering 91 and 98% of the Caucasian population, respectively. Presented in the context of several different HLA class II molecules, two epitope areas in IE1 and IE2 were recognized in about half of the analyzed donors. These data may be used to design a versatile anti-HCMV vaccine and/or immunotherapy strategy.

NOD1 cooperates with TLR2 to enhance T cell receptor-mediated activation in CD8 T cells.

Directory of Open Access Journals (Sweden)

Blandine C Mercier

Full Text Available Pattern recognition receptors (PRR, like Toll-like receptors (TLR and NOD-like receptors (NLR, are involved in the detection of microbial infections and tissue damage by cells of the innate immune system. Recently, we and others have demonstrated that TLR2 can additionally function as a costimulatory receptor on CD8 T cells. Here, we establish that the intracytosolic receptor NOD1 is expressed and functional in CD8 T cells. We show that C12-iEDAP, a synthetic ligand for NOD1, has a direct impact on both murine and human CD8 T cells, increasing proliferation and effector functions of cells activated via their T cell receptor (TCR. This effect is dependent on the adaptor molecule RIP2 and is associated with an increased activation of the NF-κB, JNK and p38 signaling pathways. Furthermore, we demonstrate that NOD1 stimulation can cooperate with TLR2 engagement on CD8 T cells to enhance TCR-mediated activation. Altogether our results indicate that NOD1 might function as an alternative costimulatory receptor in CD8 T cells. Our study provides new insights into the function of NLR in T cells and extends to NOD1 the recent concept that PRR stimulation can directly control T cell functions.

A case for hidden b anti b tetraquarks based on e{sup +}e{sup -} {yields} b anti b cross sections between {radical}(s) = 10.54 and 11.20 GeV

Energy Technology Data Exchange (ETDEWEB)

Ali, Ahmed; Hambrock, Christian [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Ahmed, Ishtiaq [Quaid-i-Azam Univ., Islamabad (Pakistan). National Centre for Physics; Aslam, M. Jamil [Quaid-i-Azam Univ., Islamabad (Pakistan). Physics Dept.

2009-11-15

We study the spectroscopy and dominant decays of the bottomonium-like tetraquarks (bound diquarks-antidiquarks), focusing on the lowest lying P-wave [bq][anti b anti q] states Y{sub [bq]} (with q=u,d), having J{sup PC}=1{sup --}. To search for them, we analyse the BABAR data obtained during an energy scan of the e{sup +}e{sup -}{yields}b anti b cross section in the range of {radical}(s)=10.54 to 11.20 GeV. We find that these data are consistent with the presence of an additional b anti b state Y{sub [bq]} with a mass of 10.90 GeV and a width of about 30 MeV apart from the {upsilon}(5S) and {upsilon}(6S) resonances. A closeup of the energy region around the Y{sub [bq]}-mass may resolve this state in terms of the two mass eigenstates, Y{sub [b,l]} and Y{sub [b,h]}, with a mass difference, estimated as about 6 MeV. We tentatively identify the state Y{sub [bq]}(10900) from the R{sub b}-scan with the state Y{sub b}(10890) observed by BELLE in the process e{sup +}e{sup -}{yields}Y{sub b}(10890){yields}{upsilon}(1S,2S){pi}{sup +}{pi}{sup -} due to their proximity in masses and decay widths. (orig.)

Measurement of $B_c^+$ production in proton-proton collisions at $\\sqrt{s}=8$ TeV

CERN Document Server

Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassen, Rolf; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Belogurov, Sergey; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Bjørnstad, Pål Marius; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Brambach, Tobias; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Brown, Henry; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew Christopher; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pascal; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Di Canto, Angelo; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gauld, Rhorry; Gavardi, Laura; Gazzoni, Giulio; Geraci, Angelo; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Gianì, Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, Vladimir; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Hunt, Philip; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jaton, Pierre; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kozlinskiy, Alexandr; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leo, Sabato; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lopez-March, Neus; Lowdon, Peter; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Machikhiliyan, Irina V; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martín Sánchez, Alexandra; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathe, Zoltan; Matteuzzi, Clara; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; McSkelly, Ben; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Moggi, Niccolò; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Katharina; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Nicol, Michelle; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Oggero, Serena; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Orlandea, Marius; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Arantza; Pal, Bilas Kanti; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parkes, Christopher; Parkinson, Christopher John; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Perrin-Terrin, Mathieu; Pescatore, Luca; Pesen, Erhan; Petridis, Konstantin; Petrolini, Alessandro; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skillicorn, Ian; Skwarnicki, Tomasz; Smith, Anthony; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Subbiah, Vijay Kartik; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szumlak, Tomasz; T'Jampens, Stephane; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Todd, Jacob; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ubeda Garcia, Mario; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Whitehead, Mark; Wicht, Jean; Wiedner, Dirk; Wilkinson, Guy; Williams, Matthew; Williams, Mike; Wilschut, Hans; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Wen Chao; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang

2015-01-01

Production of $B_c^+$ mesons in proton-proton collisions at a center-of-mass energy of 8 TeV is studied with data corresponding to an integrated luminosity of $2.0~{\\rm fb^{-1}}$ recorded by the LHCb experiment. The ratio of production cross-sections times branching fractions between the $B_c^+\\to J/\\psi \\pi^+$ and $B^+\\to J/\\psi K^+$ decays is measured as a function of transverse momentum and rapidity in the regions $0 < p_{\\rm T} < 20{\\rm GeV}/c$ and $2.0 < y < 4.5$. The ratio integrated within this kinematic range is measured to be $(0.683\\,\\pm\\,0.018\\,\\pm\\,0.009)\\%$, where the first uncertainty is statistical and the second systematic.

The role of CD154-CD40 versus CD28-B7 costimulatory pathways in regulating allogeneic Th1 and Th2 responses in vivo

DEFF Research Database (Denmark)

Kishimoto, K; Dong, V M; Issazadeh-Navikas, Shohreh

2000-01-01

We used signal transducer and activator of transcription 4 (STAT4) and STAT6 gene knockout (-/-) mice as recipients of fully mismatched cardiac allografts to study the role of T-cell costimulatory pathways in regulating allogeneic T-helper 1 (Th1) versus Th2 responses in vivo. STAT4(-/-) mice have...... impaired Th1 responses, whereas STAT6(-/-) mice do not generate normal Th2 responses. Cardiac allografts from C57BL/6 mice were transplanted into normal wild-type (WT), STAT4(-/-), and STAT6(-/-) BALB/c recipients. STAT4(-/-) and STAT6(-/-) mice rejected their grafts with the same tempo as untreated WT....... Furthermore, there was a similar differential effect of CD28-B7 versus CD154-CD40 blockade in inhibiting immune responses in animals immunized with ovalbumin and complete Freund's adjuvant. These novel data indicate that Th1 and Th2 cells are differentially regulated by CD28-B7 versus CD154-CD40 costimulation...

Vitamin E γ-Tocotrienol Inhibits Cytokine-Stimulated NF-κB Activation by Induction of Anti-Inflammatory A20 via Stress Adaptive Response Due to Modulation of Sphingolipids.

Science.gov (United States)

Wang, Yun; Park, Na-Young; Jang, Yumi; Ma, Averil; Jiang, Qing

2015-07-01

NF-κB plays a central role in pathogenesis of inflammation and cancer. Many phytochemicals, including γ-tocotrienol (γTE), a natural form of vitamin E, have been shown to inhibit NF-κB activation, but the underlying mechanism has not been identified. In this study, we show that γTE inhibited cytokine-triggered activation of NF-κB and its upstream regulator TGF-β-activated kinase-1 in murine RAW 264.7 macrophages and primary bone marrow-derived macrophages. In these cells, γTE induced upregulation of A20, an inhibitor of NF-κB. Knockout of A20 partially diminished γTE's anti-NF-κB effect, but γTE increased another NF-κB inhibitor, Cezanne, in A20(-/-) cells. In search of the reason for A20 upregulation, we found that γTE treatment increased phosphorylation of translation initiation factor 2, IκBα, and JNK, indicating induction of endoplasmic reticulum stress. Liquid chromatography-tandem mass spectrometry analyses revealed that γTE modulated sphingolipids, including enhancement of intracellular dihydroceramides, sphingoid bases in de novo synthesis of the sphingolipid pathway. Chemical inhibition of de novo sphingolipid synthesis partially reversed γTE's induction of A20 and the anti-NF-κB effect. The importance of dihydroceramide increase is further supported by the observation that C8-dihydroceramide mimicked γTE in upregulating A20, enhancing endoplasmic reticulum stress, and attenuating TNF-triggered NF-κB activation. Our study identifies a novel anti-NF-κB mechanism where A20 is induced by stress-induced adaptive response as a result of modulation of sphingolipids, and it demonstrates an immunomodulatory role of dihydrocermides. Copyright © 2015 by The American Association of Immunologists, Inc.

Heavy quark symmetry and weak decays of the b-baryons in pentaquarks with a c anti c component

Energy Technology Data Exchange (ETDEWEB)

Ali, Ahmed [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Ahmed, Ishtiaq; Rehman, Abdur [Quaid-i-Azam Univ., Islamabad (Pakistan). National Centre for Physics; Aslam, M. Jamil [Quaid-i-Azam Univ., Islamabad (Pakistan). Physics Dept.

2016-06-15

The discovery of the baryonic states P{sup +}{sub c}(4380) and P{sup +}{sub c}(4450) by the LHCb collaboration in the process pp→b anti b→Λ{sup 0}{sub b}X, followed by the decay Λ{sup 0}{sub b}→J/ψpK{sup -} has evoked a lot of theoretical interest. These states have the minimal quark content c anti cuud, as suggested by their discovery mode J/ψ p, and the preferred J{sup P} assignments are (5)/(2){sup +} for the P{sup +}{sub c}(4450) and (3)/(2){sup -} for the P{sup +}{sub c}(4380). In the compact pentaquark hypothesis, in which they are interpreted as hidden charm diquark-diquark-antiquark baryons, the assigned spin and angular momentum quantum numbers are P{sup +}{sub c}(4380)={ anti c[cu]_s_=_1[ud]_s_=_1; L_P=0, J"P=(3)/(2)"-} and P{sup +}{sub c}(4450)={ anti c[cu]_s_=_1[ud]_s_=_0; L_P=1, J"P=(5)/(2)"+}. The subscripts denote the spin of the diquarks and L{sub P}=0,1 are the orbital angular momentum quantum numbers of the pentaquarks. We point out that heavy quark limit, the spin of the light diquark in heavy baryons becomes a good quantum number, which has consequences for the decay Λ{sup 0}{sub b}→J/ψpK{sup -}. With the quantum numbers assigned above for the two pentaquarks, this would allow only the higher mass pentaquark state P{sup +}{sub c}(4450) having [ud]{sub s=0} to be produced in Λ{sup 0}{sub b} decays, whereas the lower mass state P{sup +}{sub c}(4380) having [ud]{sub s=1} is disfavored, requiring a different interpretation. Pentaquark spectrum is rich enough to accommodate a J{sup P}=(3)/(2){sup -} state, which has the correct light diquark spin { anti c[cu]_s_=_1[ud]_s_=_0; L_P=0, J"P=(3)/(2)"-} to be produced in Λ{sup 0}{sub b} decays. Assuming that the mass difference between the charmed pentaquarks which differ in the orbital angular momentum L by one unit is similar to the corresponding mass difference in the charmed baryons, m[Λ{sup +}{sub c}(2625); J{sup P}=(3)/(2){sup -}]-m[Λ{sup +}{sub c}(2286); J{sup P}=(1)/(2){sup +}]�

Synthesis of iridacarborane halide complexes [(η-9-SMe2-7,8-C2B9H10)IrX2]2 (X=Cl, Br, I)

International Nuclear Information System (INIS)

Kudinov, A.R.; Perekalin, D.S.; Petrovskij, P.V.

2001-01-01

By interaction between Na[9-SMe 2 -7,8-C 2 B 9 H 10 ] and [(Cod)IrCl] 2 (Cod - cycloocta-1,5-diene) iridium complex (η-9-SMe 2 -7,8-C 2 B 9 H 10 )Ir(Cod), which under the action of anhydrous hydrohalogenic acids HX (X=Cl, Br, I) yields iridacarborane halide complexes [(η-9-SMe 2 -7,8-C 2 B 9 H 10 )IrX 2 ] 2 , being analogs of cyclopentadienyl complexes [(C 5 Me 5 )IrX 2 ] 2 . The complexes prepared were characterized on the basis of data of elementary analysis and 1 H, 11 B NMR spectra [ru

HLA-A*01:03, HLA-A*24:02, HLA-B*08:01, HLA-B*27:05, HLA-B*35:01, HLA-B*44:02, and HLA-C*07:01 Monochain Transgenic/H-2 Class I Null Mice

DEFF Research Database (Denmark)

Boucherma, Rachid; Kridane-Miledi, Hédia; Bouziat, Romain

2013-01-01

We have generated a panel of transgenic mice expressing HLA-A*01:03, -A*24:02, -B*08:01, -B*27:05, -B*35:01, -B*44:02, or -C*07:01 as chimeric monochain molecules (i.e., appropriate HLA α1α2 H chain domains fused with a mouse α3 domain and covalently linked to human β2-microglobulin). Whereas...... a quantitative and qualitative restoration of the peripheral CD8(+) T cell repertoire, which exhibited a TCR diversity comparable with C57BL/6 WT mice. Potent epitope-specific, HLA-restricted, IFN-γ-producing CD8(+) T cell responses were generated against known reference T cell epitopes after either peptide...

Ikaros imposes a barrier to CD8+ T cell differentiation by restricting autocrine IL-2 production.

Science.gov (United States)

O'Brien, Shaun; Thomas, Rajan M; Wertheim, Gerald B; Zhang, Fuqin; Shen, Hao; Wells, Andrew D

2014-06-01

Naive CD4(+) T cells require signals from the TCR and CD28 to produce IL-2, expand, and differentiate. However, these same signals are not sufficient to induce autocrine IL-2 production by naive CD8(+) T cells, which require cytokines provided by other cell types to drive their differentiation. The basis for failed autocrine IL-2 production by activated CD8(+) cells is unclear. We find that Ikaros, a transcriptional repressor that silences IL-2 in anergic CD4(+) T cells, also restricts autocrine IL-2 production by CD8(+) T cells. We find that CD8(+) T cell activation in vitro in the absence of exogenous cytokines and CD4 help leads to marked induction of Ikaros, a known repressor of the Il2 gene. Naive murine CD8 T cells haplo-insufficient for Ikzf1 failed to upregulate Ikaros, produced autocrine IL-2, and differentiated in an IL-2-dependent manner into IFN-γ-producing CTLs in response to TCR/CD28 stimulation alone. Furthermore, Ikzf1 haplo-insufficient CD8(+) T cells were more effective at controlling Listeria infection and B16 melanoma growth in vivo, and they could provide help to neighboring, non-IL-2-producing cells to differentiate into IFN-γ-producing effectors. Therefore, by repressing autocrine IL-2 production, Ikaros ensures that naive CD8(+) T cells remain dependent on licensing by APCs and CD4(+) T cells, and it may therefore act as a cell-intrinsic safeguard against inappropriate CTL differentiation and immunopathology. Copyright © 2014 by The American Association of Immunologists, Inc.

The challenge of treating hepatitis C virus-associated cryoglobulinemic vasculitis in the era of anti-CD20 monoclonal antibodies and direct antiviral agents.

Science.gov (United States)

Roccatello, Dario; Sciascia, Savino; Rossi, Daniela; Solfietti, Laura; Fenoglio, Roberta; Menegatti, Elisa; Baldovino, Simone

2017-06-20

Mixed cryoglobulinemia syndrome (MC) is a systemic vasculitis involving kidneys, joints, skin, and peripheral nerves. While many autoimmune, lymphoproliferative, and neoplastic disorders have been associated with this disorder, hepatitis C virus (HCV) is known to be the etiologic agent in the majority of patients. Therefore, clinical research has focused on anti-viral drugs and, more recently, on the new, highly potent Direct-acting Antiviral Agents (DAAs). These drugs assure sustained virologic response (SVR) rates >90%. Nevertheless, data on their efficacy in patients with HCV-associated cryoglobulinemic vasculitis are disappointing, possibly due to the inability of the drugs to suppress the immune-mediated process once it has been triggered.Despite the potential risk of exacerbation of the infection, immunosuppression has traditionally been regarded as the first-line intervention in cryoglobulinemic vasculitis, especially if renal involvement is severe. Biologic agents have raised hopes for more manageable therapeutic approaches, and Rituximab (RTX), an anti CD20 monoclonal antibody, is the most widely used biologic drug. It has proved to be safer than conventional immunosuppressants, thus substantially changing the natural history of HCV-associated cryoglobulinemic vasculitis by providing long-term remission, especially with intensive regimens.The present review focuses on the new therapeutic opportunities offered by the combination of biological drugs, mainly Rituximab, with DAAs.

CXCR5-Dependent Entry of CD8 T Cells into Rhesus Macaque B-Cell Follicles Achieved through T-Cell Engineering.

Science.gov (United States)

Ayala, Victor I; Deleage, Claire; Trivett, Matthew T; Jain, Sumiti; Coren, Lori V; Breed, Matthew W; Kramer, Joshua A; Thomas, James A; Estes, Jacob D; Lifson, Jeffrey D; Ott, David E

2017-06-01

Follicular helper CD4 T cells, T FH , residing in B-cell follicles within secondary lymphoid tissues, are readily infected by AIDS viruses and are a major source of persistent virus despite relative control of viral replication. This persistence is due at least in part to a relative exclusion of effective antiviral CD8 T cells from B-cell follicles. To determine whether CD8 T cells could be engineered to enter B-cell follicles, we genetically modified unselected CD8 T cells to express CXC chemokine receptor 5 (CXCR5), the chemokine receptor implicated in cellular entry into B-cell follicles. Engineered CD8 T cells expressing human CXCR5 (CD8 hCXCR5 ) exhibited ligand-specific signaling and chemotaxis in vitro Six infected rhesus macaques were infused with differentially fluorescent dye-labeled autologous CD8 hCXCR5 and untransduced CD8 T cells and necropsied 48 h later. Flow cytometry of both spleen and lymph node samples revealed higher frequencies of CD8 hCXCR5 than untransduced cells, consistent with preferential trafficking to B-cell follicle-containing tissues. Confocal fluorescence microscopy of thin-sectioned lymphoid tissues demonstrated strong preferential localization of CD8 hCXCR5 T cells within B-cell follicles with only rare cells in extrafollicular locations. CD8 hCXCR5 T cells were present throughout the follicles with some observed near infected T FH In contrast, untransduced CD8 T cells were found in the extrafollicular T-cell zone. Our ability to direct localization of unselected CD8 T cells into B-cell follicles using CXCR5 expression provides a strategy to place highly effective virus-specific CD8 T cells into these AIDS virus sanctuaries and potentially suppress residual viral replication. IMPORTANCE AIDS virus persistence in individuals under effective drug therapy or those who spontaneously control viremia remains an obstacle to definitive treatment. Infected follicular helper CD4 T cells, T FH , present inside B-cell follicles represent a

Anti-CD3 Antibody Ameliorates Transfusion-Associated Graft-Versus-Host Disease in a Chemotherapy-Based Mouse Model With Busulfan and Fludarabine

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Xiaofan Li

2017-05-01

Full Text Available ABSTRACT To establish a transfusion-associated graft-versus-host disease (TA-GVHD mouse model with busulfan and fludarabine for effective treatment evaluation. BALB/c (H-2d mice were injected with busulfan (15 mg/kg and fludarabine (30 mg/kg twice a day for 4 days. The mice were transfused with 106 T cell-depleted bone marrow (TCD-BM and cells in different groups 3 days after chemotherapy: syngeneic BALB/c, MHC minor mismatch DBA/2 (H-2d, or MHC major mismatch C57BL/6(H2-b. Recipient BALB/c mice were injected with either blood only or blood+splenocyte. TA-GVHD was monitored in terms of body weight loss, clinical scores, and survival. Dexamethasone (50 mg/kg, cyclophosphamide (50 mg/kg, cyclosporine A (30 mg/kg, and anti-CD3 (1 mg/kg were injected to each group to examine the treatments. Blood transfusion alone is insufficient to induce TA-GVHD in a chemotherapy-based mouse model. A MHC-mismatched TA-GVHD model can be induced by splenocyte and blood transfusion. This MHC-mismatched TA-GVHD model was resistant to dexamethasone treatment. Treatment based on anti-CD3 monoclonal antibody slightly ameliorated TA-GVHD. Treatment effectiveness was associated with T-cell depletion following activation by anti-CD3. Busulfan and fludarabine chemotherapy regimen can be used to establish a TA-GVHD mouse model. Anti-CD3 monoclonal antibody is a potential alternative to treat TA-GVHD.

Effects of hydrostatic pressure and biaxial strains on the elastic and electronic properties of t-C8B2N2

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Zhu, Haiyan; Shi, Liwei; Li, Shuaiqi; Duan, Yifeng; Zhang, Shaobo; Xia, Wangsuo

2018-04-01

The effects of hydrostatic pressure and biaxial strains on the elastic and electronic properties of a superhard material t-C8B2N2 have been studied using first-principles calculations. The structure is proven to be mechanically and dynamically stable under the applied external forces. All the elastic constants (except C66) and elastic modulus increase (decrease) with increasing pressure and compressive (tensile) biaxial strain ɛxx. A microscopic model is used to calculate the Vicker's hardness of every single bond as well as the crystal. The hardness of t-C8B2N2 (64.7 GPa) exceeds that of c-BN (62 GPa) and increases obviously by employing pressure and compressive ɛxx. Furthermore, the Debye temperature and anisotropy of sound velocities for t-C8B2N2 have been discussed. t-C8B2N2 undergoes an indirect to direct bandgap transition when ɛxx > 2%; however, the indirect bandgap character of the material remains under pressure.

Consumption of high-dose vitamin C (1250 mg per day) enhances functional and structural properties of serum lipoprotein to improve anti-oxidant, anti-atherosclerotic, and anti-aging effects via regulation of anti-inflammatory microRNA.

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Kim, Seong-Min; Lim, So-Mang; Yoo, Jeong-Ah; Woo, Moon-Jea; Cho, Kyung-Hyun

2015-11-01

Background Although the health effects of vitamin C are well known, its physiological effect on serum lipoproteins and microRNA still remain to be investigated, especially daily consumption of a high dosage. Objectives To investigate the physiological effect of vitamin C on serum lipoprotein metabolism in terms of its anti-oxidant and anti-glycation activities, and gene expression via microRNA regulation. Methods We analyzed blood parameters and lipoprotein parameters in young subjects (n = 46, 22 ± 2 years old) including smokers who consumed a high dose of vitamin C (1250 mg) daily for 8 weeks. Results Antioxidant activity of serum was enhanced with the elevation of Vit C content in plasma during 8 weeks consumption. In the LDL fraction, the apo-B48 band disappeared at 8 weeks post-consumption in all subjects. In the HDL fraction, apoA-I expression was enhanced by 20% at 8 weeks, especially in male smokers. In the lipoprotein fraction, all subjects showed significantly reduced contents of advanced glycated end products and reactive oxygen species (ROS). Triglyceride (TG) contents in each LDL and HDL fraction were significantly reduced in all groups following the Vit C consumption, suggesting that the lipoprotein was changed to be more anti-inflammatory and atherogenic properties. Phagocytosis of LDL, which was purified from each individual, into macrophages was significantly reduced at 8-weeks post-consumption of vitamin C. Anti-inflammatory and anti-senescence effects of HDL from all subjects were enhanced after the 8-weeks consumption. The expression level of microRNA 155 in HDL3 was reduced by 49% and 75% in non-smokers and smokers, respectively. Conclusion The daily consumption of a high dose of vitamin C for 8 weeks resulted in enhanced anti-senescence and anti-atherosclerotic effects via an improvement of lipoprotein parameters and microRNA expression through anti-oxidation and anti-glycation, especially in smokers.

Modulation of Cytokine Production by Drugs with Antiepileptic or Mood Stabilizer Properties in Anti-CD3- and Anti-CD40-Stimulated Blood In Vitro

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Hubertus Himmerich

2014-01-01

Full Text Available Increased cytokine production possibly due to oxidative stress has repeatedly been shown to play a pivotal role in the pathophysiology of epilepsy and bipolar disorder. Recent in vitro and animal studies of valproic acid (VPA report antioxidative and anti-inflammatory properties, and suppression of interleukin (IL-6 and tumor necrosis factor (TNF-α. We tested the effect of drugs with antiepileptic or mood stabilizer properties, namely, primidone (PRM, carbamazepine (CBZ, levetiracetam (LEV, lamotrigine (LTG, VPA, oxcarbazepine (OXC, topiramate (TPM, phenobarbital (PB, and lithium on the production of the following cytokines in vitro: interleukin (IL-1β, IL-2, IL-4, IL-6, IL-17, IL-22, and TNF-α. We performed a whole blood assay with stimulated blood of 14 healthy female subjects. Anti-human CD3 monoclonal antibody OKT3, combined with 5C3 antibody against CD40, was used as stimulant. We found a significant reduction of IL-1 and IL-2 levels with all tested drugs other than lithium in the CD3/5C3-stimulated blood; VPA led to a decrease in IL-1β, IL-2, IL-4, IL-6, IL-17, and TNF-α production, which substantiates and adds knowledge to current hypotheses on VPA’s anti-inflammatory properties.

Functional dichotomy between NKG2D and CD28-mediated co-stimulation in human CD8+ T cells.

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Kamalakannan Rajasekaran

2010-09-01

Full Text Available Both CD28 and NKG2D can function as co-stimulatory receptors in human CD8+ T cells. However, their independent functional contributions in distinct CD8+ T cell subsets are not well understood. In this study, CD8+ T cells in human peripheral blood- and lung-derived lymphocytes were analyzed for CD28 and NKG2D expression and function. We found a higher level of CD28 expression in PBMC-derived naïve (CD45RA+CD27+ and memory (CD45RA-CD27+ CD8+ T cells (CD28Hi, while its expression was significantly lower in effector (CD45RA+CD27- CD8+ T cells (CD28Lo. Irrespective of the differences in the CD28 levels, NKG2D expression was comparable in all three CD8+ T cell subsets. CD28 and NKG2D expressions followed similar patterns in human lung-resident GILGFVFTL/HLA-A2-pentamer positive CD8+ T cells. Co-stimulation of CD28Lo effector T cells via NKG2D significantly increased IFN-γ and TNF-α levels. On the contrary, irrespective of its comparable levels, NKG2D-mediated co-stimulation failed to augment IFN-γ and TNF-α production in CD28Hi naïve/memory T cells. Additionally, CD28-mediated co-stimulation was obligatory for IL-2 generation and thereby its production was limited only to the CD28Hi naïve/memory subsets. MICA, a ligand for NKG2D was abundantly expressed in the tracheal epithelial cells, validating the use of NKG2D as the major co-stimulatory receptor by tissue-resident CD8+ effector T cells. Based on these findings, we conclude that NKG2D may provide an expanded level of co-stimulation to tissue-residing effector CD8+ T cells. Thus, incorporation of co-stimulation via NKG2D in addition to CD28 is essential to activate tumor or tissue-infiltrating effector CD8+ T cells. However, boosting a recall immune response via memory CD8+ T cells or vaccination to stimulate naïve CD8+ T cells would require CD28-mediated co-stimulation.

CD86 and beta2-adrenergic receptor signaling pathways, respectively, increase Oct-2 and OCA-B Expression and binding to the 3'-IgH enhancer in B cells.

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Podojil, Joseph R; Kin, Nicholas W; Sanders, Virginia M

2004-05-28

Stimulation of CD86 (formerly known as B7-2) and/or the beta2-adrenergic receptor on a CD40 ligand/interleukin-4-activated B cell increased the rate of mature IgG1 transcription. To identify the mechanism responsible for this effect, we determined whether CD86 and/or beta2-adrenergic receptor stimulation regulated transcription factor expression and binding to the 3'-IgH enhancer in vitro and in vivo. We showed that CD86 stimulation increased the nuclear localization of NF-kappaB1 (p50) and phosphorylated RelA (p65) and increased Oct-2 expression and binding to the 3'-IgH enhancer, in a protein kinase C-dependent manner. These effects were lost when CD86-deficient or NF-kappaB1-deficient B cells were used. CD86 stimulation also increased the level of IkappaB-alpha phosphorylation but in a protein kinase C-independent manner. Beta2-adrenergic receptor stimulation increased CREB phosphorylation, OCA-B expression, and OCA-B binding to the 3'-IgH enhancer in a protein kinase A-dependent manner, an effect lost when beta2-adrenergic receptor-deficient B cells were used. Also, the beta2-adrenergic receptor-induced increase in the level of mature IgG1 transcript was lost when OCA-B-deficient B cells were used. These data are the first to show that CD86 stimulation up-regulates the expression of the transcription factor Oct-2 in a protein kinase C- and NF-kappaB1-dependent manner, and that beta2-adrenergic receptor stimulation up-regulates the expression of the coactivator OCA-B in a protein kinase A-dependent manner to cooperate with Oct-2 binding to the 3'-IgH enhancer.

The role of CD80/CD86 in generation and maintenance of functional virus-specific CD8+ T cells in mice infected with lymphocytic choriomeningitis virus

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Grujic, Mirjana; Bartholdy, Christina; Remy, Melissa

2010-01-01

Lymphocytic choriomeningitis virus (LCMV)-specific CD8(+) T cell responses are considered to be independent of CD28-B7 costimulation. However, the LCMV-specific response has never been evaluated in B7.1/B7.2(-/-) mice. For this reason, we decided to study the T cell response in B7.1/B7.2(-/-) mice......, but no chronic infection. Taken together, these results indicate that B7 costimulation is required for induction and maintenance of LCMV-specific CD8(+) T cell memory, irrespective of the LCMV strain used for priming. However, the erosion of CD8(+) T cell memory in B7.1/B7.2(-/-) mice was more pronounced...

Impact of CD68/(CD3+CD20 ratio at the invasive front of primary tumors on distant metastasis development in breast cancer.

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Noemí Eiró

Full Text Available Tumors are infiltrated by macrophages, T and B-lymphocytes, which may favor tumor development by promoting angiogenesis, growth and invasion. The aim of this study was to investigate the clinical relevance of the relative amount of macrophages (CD68⁺, T-cells (CD3⁺ and B-cells (CD20⁺ at the invasive front of breast carcinomas, and the expression of matrix metalloproteases (MMPs and their inhibitors (TIMPs either at the invasive front or at the tumor center. We performed an immunohistochemical study counting CD3, CD20 and CD68 positive cells at the invasive front, in 102 breast carcinomas. Also, tissue sections were stained with MMP-2, -9, -11, -14 and TIMP-2 antibodies, and immunoreactivity location, percentage of reactive area and intensity were determined at the invasive front and at the tumor center. The results showed that an increased CD68 count and CD68/(CD3+CD20 ratio were directly associated with both MMP-11 and TIMP-2 expression by mononuclear inflammatory cells at the tumor center (p = 0.041 and p = 0.025 for CD68 count and p = 0.001 and p = 0.045 for ratio, respectively for MMP-11 and TIMP-2. In addition, a high CD68/(CD3+CD20 ratio (>0.05 was directly associated with a higher probability of shortened relapse-free survival. Multivariate analysis revealed that CD68/(CD3+CD20 ratio was an independent factor associated with distant relapse-free survival (RR: 2.54, CI: (1.23-5.24, p<0.01. Therefore, CD68/(CD3+CD20 ratio at the invasive front could be used as an important prognostic marker.

T CD3+CD8+ Lymphocytes Are More Susceptible for Apoptosis in the First Trimester of Normal Human Pregnancy

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Dorota Darmochwal-Kolarz

2014-01-01

Full Text Available Aims. Normal human pregnancy is a complex process of many immunoregulatory mechanisms which protect fetus from the activation of the maternal immune system. The aim of the study was to investigate the apoptosis of lymphocytes in peripheral blood of normal pregnant patients and healthy nonpregnant women. Methods. Sixty pregnant women and 17 nonpregnant women were included in the study. Lymphocytes were isolated and labeled with anti-CD3, anti-CD4, and anti-CD8 monoclonal antibodies. Apoptosis was detected by CMXRos staining and analyzed using the flow cytometric method. Results. We found significantly higher apoptosis of total lymphocytes in peripheral blood of pregnant patients when compared to healthy nonpregnant women. The percentage of apoptotic T CD3+CD8+ cells in the first trimester was significantly higher when compared to the third trimester of normal pregnancy. The ratio of T CD3+CD4+ : T CD3+CD8+ apoptotic lymphocytes was significantly lower in the first trimester when compared to other trimesters of pregnancy and to both of the phases of the menstrual cycle. Conclusions. The higher apoptosis of T CD3+CD8+ lymphocytes and the lower ratio of T CD3+CD4+ : T CD3+CD8+ apoptotic cells in the first trimester of normal pregnancy may suggest a higher susceptibility of T CD3+CD8+ cells for apoptosis as a protective mechanism at the early stage of pregnancy.

Measurement of CD8+ and CD4+ T Cell Frequencies Specific for EBV LMP1 and LMP2a Using mRNA-Transfected DCs.

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Dae-Hee Sohn

Full Text Available An EBV-specific cellular immune response is associated with the control of EBV-associated malignancies and lymphoproliferative diseases, some of which have been successfully treated by adoptive T cell therapy. Therefore, many methods have been used to measure EBV-specific cellular immune responses. Previous studies have mainly used autologous EBV-transformed B-lymphoblastoid cell lines (B-LCLs, recombinant viral vectors transfected or peptide pulsed dendritic cells (DCs as stimulators of CD8(+ and CD4(+ T lymphocytes. In the present study, we used an interferon-γ (IFN-γ enzyme-linked immunospot (ELISPOT assay by using isolated CD8(+ and CD4(+ T cells stimulated with mRNA-transfected DCs. The frequency of latent membrane protein 1 (LMP1-specific IFN-γ producing CD4(+ T cells was significantly higher than that of LMP2a. The frequency of IFN-γ producing CD4(+ T cells was significantly correlated with that of CD8(+ T cells in LMP1-specific immune responses (r = 0.7187, Pc < 0.0001. To determine whether there were changes in LMP1- or LMP2a-specific immune responses, subsequent peripheral blood mononuclear cells (PBMCs samples were analyzed. Significant changes were observed in 5 of the 10 donors examined, and CD4(+ T cell responses showed more significant changes than CD8(+ T cell responses. CD8(+ and CD4(+ T cells from EBV-seropositive donors secreted only the Th1 cytokines IFN-γ, TNF-α, and IL-2, while Th2 (IL-4 and Th17 (IL-17a cytokines were not detected. CD4(+ T cells secreted significantly higher cytokine levels than did CD8(+ T cells. Analysis of EBV-specific T cell responses using autologous DCs transfected with mRNA might provide a comprehensive tool for monitoring EBV infection and new insights into the pathogenesis of EBV-associated diseases.

Human Interferon Alpha2a as Anti Hepatitis B and C

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Ratih A. Ningrum

2017-12-01

Full Text Available Hepatitis is an inflammation of the liver mainly caused by hepatitis viruses. There are 5 different types of hepatitis based on the infecting virus; A, B, C, D and E. Hepatitis B and C are chronic diseases that potentially develop into hepatocarcinoma and cirrhosis on unappropriate treatments. World Health Organization (WHO stated that currently 350 million people worldwide are living with chronic hepatitis B and 150 million people are living with Hepatitis C. The mortality rate in the world due to hepatitis is about 1.5 million people per year. The human interferon alpha2a (hIFNα2a is a therapeutic protein used as therapeutic protein for hepatitis B and C. This review discusses the hepatitis B (HBV and C (HCV viruses, mechanisms of hIFNα2a as antivirus through signal transduction pathway and improvement of hIFNα2a properties by protein modification. The application of recombinant hIFNα2a (rhIFNα2a in the treatment of hepatitis B and C that recommended by European Association for The Study of Liver (EASL and the viral resistance mechanism are also included. The status of hepatitis B and C and the development of rhIFNα2a is also described as well.