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Sample records for benchmarking b-cell epitope

  1. Reliable B cell epitope predictions: impacts of method development and improved benchmarking

    DEFF Research Database (Denmark)

    Kringelum, Jens Vindahl; Lundegaard, Claus; Lund, Ole;

    2012-01-01

    evaluation data set improved from 0.712 to 0.727. Our results thus demonstrate that given proper benchmark definitions, B-cell epitope prediction methods achieve highly significant predictive performances suggesting these tools to be a powerful asset in rational epitope discovery. The updated version......The interaction between antibodies and antigens is one of the most important immune system mechanisms for clearing infectious organisms from the host. Antibodies bind to antigens at sites referred to as B-cell epitopes. Identification of the exact location of B-cell epitopes is essential in several...... of B-cell epitopes has been moderate. Several issues regarding the evaluation data sets may however have led to the performance values being underestimated: Rarely, all potential epitopes have been mapped on an antigen, and antibodies are generally raised against the antigen in a given biological...

  2. The Relationship between B-cell Epitope and Mimotope Sequences.

    Science.gov (United States)

    Zhang, Chunhua; Li, Yunyun; Tang, Weina; Zhou, Zhiguo; Sun, Pingping; Ma, Zhiqiang

    2016-01-01

    B-cell epitope is a group of residues which is on the surface of an antigen. It invokes humoral responses. Locating B-cell epitope is important for effective vaccine design, and the development of diagnostic reagents. Mimotope-based B-cell epitope prediction method is a kind of conformational B-cell epitope prediction, and the core idea of the method is mapping the mimotope sequences which are obtained from a random phage display library. However, current mimotope-based B-cell epitope prediction methods cannot maintain a high degree of satisfaction in the circumstances of employing only mimotope sequences. In this study, we did a multi-perspective analysis on parameters for conformational B-cell epitopes and characteristics between epitope and mimotope on a benchmark datasets which contains 67 mimotope sets, corresponding to 40 unique complex structures. In these 67 cases, there are 25 antigen-antibody complexes and 42 protein-protein interactions. We analyzed the two parts separately. The results showed the mimotope sequences do have some epitope features, but there are also some epitope properties that mimotope sequences do not contain. In addition, the numbers of epitope segments with different lengths were obviously different between the antigen-antibody complexes and the protein-protein interactions. This study reflects how similar do mimotope sequence and genuine epitopes have; and evaluates existing mimotope-based B-cell epitope prediction methods from a novel viewpoint. PMID:26715528

  3. In silico quantitative prediction of B-cell epitope

    Directory of Open Access Journals (Sweden)

    Raúl Isea

    2015-11-01

    Full Text Available This paper shows a computational approach for quantitative prediction of B cell epitopes. The function was defined, which reflects the average value of B epitopes, according to eight predictors of different B epitopes, as well as structural and energetic considerations of the origin protein. The proposed methodology could be useful to develop both dengue and chikungunya vaccines

  4. In silico quantitative prediction of B-cell epitope

    OpenAIRE

    Raúl Isea

    2015-01-01

    This paper shows a computational approach for quantitative prediction of B cell epitopes. The function was defined, which reflects the average value of B epitopes, according to eight predictors of different B epitopes, as well as structural and energetic considerations of the origin protein. The proposed methodology could be useful to develop both dengue and chikungunya vaccines

  5. Identifying Novel B Cell Epitopes within Toxoplasma gondii GRA6.

    Science.gov (United States)

    Wang, Yanhua; Wang, Guangxiang; Cai, Jian Ping

    2016-08-01

    The study of antigenic epitopes from Toxoplasma gondii has not only enhanced our understanding of the structure and function of antigens, the reactions between antigens and antibodies, and many other aspects of immunology, but it also plays a significant role in the development of new diagnostic reagents and vaccines. In the present study, T. gondii GRA6 epitopes were identified using bioinformatics tools and a synthetic peptide technique. The potential B cell epitopes of GRA6 predicted by bioinformatics tools concentrated upon 3 regions of GRA6, 1-20 aa, 44-103 aa, and 172-221 aa. Ten shorter peptides from the 3 regions were synthesized and assessed by ELISA using pig sera from different time points after infection. Three of the 10 peptides (amino acids 44-63, 172-191, and 192-211) tested were recognized by all sera and determined to be immunodominant B-cell epitopes of GRA6. The results indicated that we precisely and accurately located the T. gondii GRA6 epitopes using pig sera collected at different time points after infection. The identified epitopes may be very useful for further studies of epitope-based vaccines and diagnostic reagents. PMID:27658594

  6. Conformational B-Cell Epitopes Prediction from Sequences Using Cost-Sensitive Ensemble Classifiers and Spatial Clustering

    Directory of Open Access Journals (Sweden)

    Jian Zhang

    2014-01-01

    Full Text Available B-cell epitopes are regions of the antigen surface which can be recognized by certain antibodies and elicit the immune response. Identification of epitopes for a given antigen chain finds vital applications in vaccine and drug research. Experimental prediction of B-cell epitopes is time-consuming and resource intensive, which may benefit from the computational approaches to identify B-cell epitopes. In this paper, a novel cost-sensitive ensemble algorithm is proposed for predicting the antigenic determinant residues and then a spatial clustering algorithm is adopted to identify the potential epitopes. Firstly, we explore various discriminative features from primary sequences. Secondly, cost-sensitive ensemble scheme is introduced to deal with imbalanced learning problem. Thirdly, we adopt spatial algorithm to tell which residues may potentially form the epitopes. Based on the strategies mentioned above, a new predictor, called CBEP (conformational B-cell epitopes prediction, is proposed in this study. CBEP achieves good prediction performance with the mean AUC scores (AUCs of 0.721 and 0.703 on two benchmark datasets (bound and unbound using the leave-one-out cross-validation (LOOCV. When compared with previous prediction tools, CBEP produces higher sensitivity and comparable specificity values. A web server named CBEP which implements the proposed method is available for academic use.

  7. Conformational B-cell epitopes prediction from sequences using cost-sensitive ensemble classifiers and spatial clustering.

    Science.gov (United States)

    Zhang, Jian; Zhao, Xiaowei; Sun, Pingping; Gao, Bo; Ma, Zhiqiang

    2014-01-01

    B-cell epitopes are regions of the antigen surface which can be recognized by certain antibodies and elicit the immune response. Identification of epitopes for a given antigen chain finds vital applications in vaccine and drug research. Experimental prediction of B-cell epitopes is time-consuming and resource intensive, which may benefit from the computational approaches to identify B-cell epitopes. In this paper, a novel cost-sensitive ensemble algorithm is proposed for predicting the antigenic determinant residues and then a spatial clustering algorithm is adopted to identify the potential epitopes. Firstly, we explore various discriminative features from primary sequences. Secondly, cost-sensitive ensemble scheme is introduced to deal with imbalanced learning problem. Thirdly, we adopt spatial algorithm to tell which residues may potentially form the epitopes. Based on the strategies mentioned above, a new predictor, called CBEP (conformational B-cell epitopes prediction), is proposed in this study. CBEP achieves good prediction performance with the mean AUC scores (AUCs) of 0.721 and 0.703 on two benchmark datasets (bound and unbound) using the leave-one-out cross-validation (LOOCV). When compared with previous prediction tools, CBEP produces higher sensitivity and comparable specificity values. A web server named CBEP which implements the proposed method is available for academic use. PMID:25045691

  8. Analysis of Conformational B-Cell Epitopes in the Antibody-Antigen Complex Using the Depth Function and the Convex Hull.

    Directory of Open Access Journals (Sweden)

    Wei Zheng

    Full Text Available The prediction of conformational b-cell epitopes plays an important role in immunoinformatics. Several computational methods are proposed on the basis of discrimination determined by the solvent-accessible surface between epitopes and non-epitopes, but the performance of existing methods is far from satisfying. In this paper, depth functions and the k-th surface convex hull are used to analyze epitopes and exposed non-epitopes. On each layer of the protein, we compute relative solvent accessibility and four different types of depth functions, i.e., Chakravarty depth, DPX, half-sphere exposure and half space depth, to analyze the location of epitopes on different layers of the proteins. We found that conformational b-cell epitopes are rich in charged residues Asp, Glu, Lys, Arg, His; aliphatic residues Gly, Pro; non-charged residues Asn, Gln; and aromatic residue Tyr. Conformational b-cell epitopes are rich in coils. Conservation of epitopes is not significantly lower than that of exposed non-epitopes. The average depths (obtained by four methods for epitopes are significantly lower than that of non-epitopes on the surface using the Wilcoxon rank sum test. Epitopes are more likely to be located in the outer layer of the convex hull of a protein. On the benchmark dataset, the cumulate 10th convex hull covers 84.6% of exposed residues on the protein surface area, and nearly 95% of epitope sites. These findings may be helpful in building a predictor for epitopes.

  9. B-Cell Receptor Epitope Recognition Correlates With the Clinical Course of Chronic Lymphocytic Leukemia

    NARCIS (Netherlands)

    Binder, Mascha; Mueller, Fabian; Jackst, Antje; Lechenne, Barbara; Pantic, Milena; Bacher, Ulrike; Eulenburg, Christine Zu; Veelken, Hendrik; Mertelsmann, Roland; Pasqualini, Renata; Arap, Wadih; Trepel, Martin

    2011-01-01

    BACKGROUND: B-cell receptors (BCRs) and their recognition of specific epitopes may play a pivotal role in the development and progression of chronic lymphocytic leukemia (CLL). In this study, the authors set up a model system to explore epitope reactivity and its clinical relevance in CLL. METHODS:

  10. Synthetic B-Cell Epitopes Eliciting Cross-Neutralizing Antibodies: Strategies for Future Dengue Vaccine.

    Directory of Open Access Journals (Sweden)

    Babu Ramanathan

    Full Text Available Dengue virus (DENV is a major public health threat worldwide. A key element in protection from dengue fever is the neutralising antibody response. Anti-dengue IgG purified from DENV-2 infected human sera showed reactivity against several peptides when evaluated by ELISA and epitope extraction techniques. A multi-step computational approach predicted six antigenic regions within the E protein of DENV-2 that concur with the 6 epitopes identified by the combined ELISA and epitope extraction approach. The selected peptides representing B-cell epitopes were attached to a known dengue T-helper epitope and evaluated for their vaccine potency. Immunization of mice revealed two novel synthetic vaccine constructs that elicited good humoral immune responses and produced cross-reactive neutralising antibodies against DENV-1, 2 and 3. The findings indicate new directions for epitope mapping and contribute towards the future development of multi-epitope based synthetic peptide vaccine.

  11. Synthetic B-Cell Epitopes Eliciting Cross-Neutralizing Antibodies: Strategies for Future Dengue Vaccine.

    Science.gov (United States)

    Ramanathan, Babu; Poh, Chit Laa; Kirk, Kristin; McBride, William John Hannan; Aaskov, John; Grollo, Lara

    2016-01-01

    Dengue virus (DENV) is a major public health threat worldwide. A key element in protection from dengue fever is the neutralising antibody response. Anti-dengue IgG purified from DENV-2 infected human sera showed reactivity against several peptides when evaluated by ELISA and epitope extraction techniques. A multi-step computational approach predicted six antigenic regions within the E protein of DENV-2 that concur with the 6 epitopes identified by the combined ELISA and epitope extraction approach. The selected peptides representing B-cell epitopes were attached to a known dengue T-helper epitope and evaluated for their vaccine potency. Immunization of mice revealed two novel synthetic vaccine constructs that elicited good humoral immune responses and produced cross-reactive neutralising antibodies against DENV-1, 2 and 3. The findings indicate new directions for epitope mapping and contribute towards the future development of multi-epitope based synthetic peptide vaccine. PMID:27223692

  12. Determination of B-Cell Epitopes in Patients with Celiac Disease: Peptide Microarrays.

    Directory of Open Access Journals (Sweden)

    Rok Seon Choung

    Full Text Available Most antibodies recognize conformational or discontinuous epitopes that have a specific 3-dimensional shape; however, determination of discontinuous B-cell epitopes is a major challenge in bioscience. Moreover, the current methods for identifying peptide epitopes often involve laborious, high-cost peptide screening programs. Here, we present a novel microarray method for identifying discontinuous B-cell epitopes in celiac disease (CD by using a silicon-based peptide array and computational methods.Using a novel silicon-based microarray platform with a multi-pillar chip, overlapping 12-mer peptide sequences of all native and deamidated gliadins, which are known to trigger CD, were synthesized in situ and used to identify peptide epitopes.Using a computational algorithm that considered disease specificity of peptide sequences, 2 distinct epitope sets were identified. Further, by combining the most discriminative 3-mer gliadin sequences with randomly interpolated3- or 6-mer peptide sequences, novel discontinuous epitopes were identified and further optimized to maximize disease discrimination. The final discontinuous epitope sets were tested in a confirmatory cohort of CD patients and controls, yielding 99% sensitivity and 100% specificity.These novel sets of epitopes derived from gliadin have a high degree of accuracy in differentiating CD from controls, compared with standard serologic tests. The method of ultra-high-density peptide microarray described here would be broadly useful to develop high-fidelity diagnostic tests and explore pathogenesis.

  13. Towards a consensus on datasets and evaluation metrics for developing B-cell epitope prediction tools

    DEFF Research Database (Denmark)

    Greenbaum, Jason A.; Andersen, Pernille; Blythe, Martin;

    2007-01-01

    and immunology communities. Improving the accuracy of B-cell epitope prediction methods depends on a community consensus on the data and metrics utilized to develop and evaluate such tools. A workshop, sponsored by the National Institute of Allergy and Infectious Disease (NIAID), was recently held in Washington......, DC to discuss the current state of the B-cell epitope prediction field. Many of the currently available tools were surveyed and a set of recommendations was devised to facilitate improvements in the currently existing tools and to expedite future tool development. An underlying theme...... of the recommendations put forth by the panel is increased collaboration among research groups. By developing common datasets, standardized data formats, and the means with which to consolidate information, we hope to greatly enhance the development of B-cell epitope prediction tools. (c) 2007 John Wiley & Sons, Ltd....

  14. B-cell epitope mapping for the design of vaccines and effective diagnostics

    Directory of Open Access Journals (Sweden)

    Tarek A. Ahmad

    2016-01-01

    Full Text Available The increasing resistance of many microbial strains to antibiotics, delayed laboratory results, and side effects of many chemotherapeutics has raised the need to search for sensitive diagnostics and new prophylactic strategies especially prevention by vaccination. Understanding the epitope/antibody interaction is the key to constructing potent vaccines and effective diagnostics. B-cell epitope mapping is a promising approach to identifying the main antigenic determinants of microorganisms, in special concern the discontinuous conformational ones. Epitope-based vaccines have remarkable privilege over the conventional ones since they are specific, able to avoid undesirable immune responses, generate long lasting immunity, and are reasonably cheaper. This up-to-date review discusses and compares the different physical, computational, and molecular methods that have been used in epitope mapping. The role of each method in the identification of potent epitopes in viruses, bacteria, fungi, parasites, as well as human diseases are tagged and documented. Simultaneously, frequent combinatorial methods are highlighted. The article aims to assist researchers to design the most suitable protocol for mapping their B-cell epitopes.

  15. Epitope-driven DNA vaccine design employing immunoinformatics against B-cell lymphoma: a biotech's challenge.

    Science.gov (United States)

    Iurescia, Sandra; Fioretti, Daniela; Fazio, Vito Michele; Rinaldi, Monica

    2012-01-01

    DNA vaccination has been widely explored to develop new, alternative and efficient vaccines for cancer immunotherapy. DNA vaccines offer several benefits such as specific targeting, use of multiple genes to enhance immunity and reduced risk compared to conventional vaccines. Rapid developments in molecular biology and immunoinformatics enable rational design approaches. These technologies allow construction of DNA vaccines encoding selected tumor antigens together with molecules to direct and amplify the desired effector pathways, as well as highly targeted vaccines aimed at specific epitopes. Reliable predictions of immunogenic T cell epitope peptides are crucial for rational vaccine design and represent a key problem in immunoinformatics. Computational approaches have been developed to facilitate the process of epitope detection and show potential applications to the immunotherapeutic treatment of cancer. In this review a number of different epitope prediction methods are briefly illustrated and effective use of these resources to support experimental studies is described. Epitope-driven vaccine design employs these bioinformatics algorithms to identify potential targets of vaccines against cancer. In this paper the selection of T cell epitopes to develop epitope-based vaccines, the need for CD4(+) T cell help for improved vaccines and the assessment of vaccine performance against tumor are reviewed. We focused on two applications, namely prediction of novel T cell epitopes and epitope enhancement by sequence modification, and combined rationale design with bioinformatics for creation of new synthetic mini-genes. This review describes the development of epitope-based DNA vaccines and their antitumor effects in preclinical research against B-cell lymphoma, corroborating the usefulness of this platform as a potential tool for cancer therapy. Achievements in the field of DNA vaccines allow to overcome hurdles to clinical translation. In a scenario where the vaccine

  16. Docking of B-cell epitope antigen to specific hepatitis B antibody

    Indian Academy of Sciences (India)

    R Rajkannan; E J Padma Malar

    2007-09-01

    The interaction of pres1 region of hepatitis B virus B-cell epitope antigen with specific hepatitis B neutralizing monoclonal antibody was examined by docking study. We modelled the 3D complex structure of B-cell epitope antigen residues CTTPAQGNSMFPSCCCTKPTDGNCY by homology modelling and docked it with the crystal structure of monoclonal antibody specific for the pres1 region of the hepatitis B virus. At the optimized docked conformation, the interactions between the amino acids of antigen and antibody were examined. It is found that the docked complex is stabilized by 59.3 kcal/mol. The stability of the docked antigen-antibody complex is due to hydrogen bonding and van der Waals interactions. The amino acids of the antigen and antibody responsible for the interaction were identified.

  17. Full protection of swine against foot-and-mouth disease by a bivalent B-cell epitope dendrimer peptide

    NARCIS (Netherlands)

    Blanco, Esther; Guerra, Beatriz; Torre, de la Beatriz; Defaus, Sira; Dekker, A.; Andreu, D.; Sobrino, Francisco

    2016-01-01

    Foot-and-mouth disease virus (FMDV) causes a highly contagious disease of cloven-hoofed animals. We have reported (Cubillos et al., 2008) that a synthetic dendrimeric peptide consisting of four copies of a B-cell epitope [VP1(136–154)] linked through thioether bonds to a T-cell epitope [3A(21–35)] o

  18. Identification of a Coccidioides immitis antigen 2 domain that expresses B-cell-reactive epitopes.

    OpenAIRE

    Zhu, Y; Tryon, V; Magee, D M; Cox, R. A.

    1997-01-01

    Antigen 2 (Ag2), a major immunoreactive component of Coccidioides immitis mycelium- and spherule-phase cell walls, was recently cloned in our laboratory and was shown to elicit T-cell responses in Coccidioides-immune mice. In this investigation, we evaluated recombinant Ag2 (rAg2) and PCR-generated Ag2 truncations for expression of B-cell-reactive epitopes in enzyme-linked immunosorbent and immunoblot assays with sera from patients with active coccidioidomycosis, a hyperimmune goat anti-Ag2 s...

  19. Rabbit hemorrhagic disease virus capsid, a versatile platform for foreign B-cell epitope display inducing protective humoral immune responses.

    Science.gov (United States)

    Moreno, Noelia; Mena, Ignacio; Angulo, Iván; Gómez, Yolanda; Crisci, Elisa; Montoya, María; Castón, José R; Blanco, Esther; Bárcena, Juan

    2016-01-01

    Virus-like particles (VLPs), comprised of viral structural proteins devoid of genetic material, are tunable nanoparticles that can be chemically or genetically engineered, to be used as platforms for multimeric display of foreign antigens. Here, we report the engineering of chimeric VLPs, derived from rabbit hemorrhagic disease virus (RHDV) for presentation of foreign B-cell antigens to the immune system. The RHDV capsid comprises 180 copies of a single capsid subunit (VP60). To evaluate the ability of chimeric RHDV VLPs to elicit protective humoral responses against foreign antigens, we tested two B-cell epitopes: a novel neutralizing B-cell epitope, derived from feline calicivirus capsid protein, and a well characterized B-cell epitope from the extracellular domain of influenza A virus M2 protein (M2e). We generated sets of chimeric RHDV VLPs by insertion of the foreign B-cell epitopes at three different locations within VP60 protein (which involved different levels of surface accessibility) and in different copy numbers per site. The immunogenic potential of the chimeric VLPs was analyzed in the mouse model. The results presented here indicated that chimeric RHDV VLPs elicit potent protective humoral responses against displayed foreign B-cell epitopes, demonstrated by both, in vitro neutralization and in vivo protection against a lethal challenge. PMID:27549017

  20. Fine mapping and conservation analysis of linear B-cell epitopes of peste des petits ruminants virus nucleoprotein.

    Science.gov (United States)

    Yu, Ruisong; Fan, Xiaoming; Xu, Wanxiang; Li, Wentao; Dong, Shijuan; Zhu, Yumin; He, Yaping; Tang, Haiping; Du, Rong; Li, Zhen

    2015-01-30

    Nucleoprotein (NP) is the most abundant and highly immunogenic protein of morbillivirus, and is presently the basis of most diagnostic assays for peste des petits ruminants virus (PPRV). In this study, fine epitope mapping and conservation analysis of linear B-cell epitopes on the PPRV NP has been undertaken using biosynthetic peptides. Nineteen linear B-cell epitopes were identified and their corresponding minimal motifs were located on the NP of PPRV China/Tibet/Geg/07-30. Conservation analysis indicated that ten of the 19 minimal motifs were conserved among 46 PPRV strains. Peptides containing the minimal motifs were recognized using anti-PPRV serum from a goat immunized with PPRV vaccine strain Nigeria 75/1. Identified epitopes and their motifs improve our understanding of the antigenic characteristics of PPRV NP and provide a basis for the development of epitope-based diagnostic assays. PMID:25465659

  1. B-Pred, a structure based B-cell epitopes prediction server

    Directory of Open Access Journals (Sweden)

    Giacò L

    2012-07-01

    Full Text Available Luciano Giacò,1 Massimo Amicosante,2 Maurizio Fraziano,1 Pier Federico Gherardini,1 Gabriele Ausiello,1 Manuela Helmer-Citterich,1 Vittorio Colizzi,1 Andrea Cabibbo11Department of Biology, 2Department of Internal Medicine, University of Rome "Tor Vergata", Rome, ItalyAbstract: The ability to predict immunogenic regions in selected proteins by in-silico methods has broad implications, such as allowing a quick selection of potential reagents to be used as diagnostics, vaccines, immunotherapeutics, or research tools in several branches of biological and biotechnological research. However, the prediction of antibody target sites in proteins using computational methodologies has proven to be a highly challenging task, which is likely due to the somewhat elusive nature of B-cell epitopes. This paper proposes a web-based platform for scoring potential immunological reagents based on the structures or 3D models of the proteins of interest. The method scores a protein's peptides set, which is derived from a sliding window, based on the average solvent exposure, with a filter on the average local model quality for each peptide. The platform was validated on a custom-assembled database of 1336 experimentally determined epitopes from 106 proteins for which a reliable 3D model could be obtained through standard modeling techniques. Despite showing poor sensitivity, this method can achieve a specificity of 0.70 and a positive predictive value of 0.29 by combining these two simple parameters. These values are slightly higher than those obtained with other established sequence-based or structure-based methods that have been evaluated using the same epitopes dataset. This method is implemented in a web server called B-Pred, which is accessible at http://immuno.bio.uniroma2.it/bpred. The server contains a number of original features that allow users to perform personalized reagent searches by manipulating the sliding window's width and sliding step, changing the

  2. Babesia bigemina: identification of B cell epitopes associated with parasitized erythrocytes.

    Science.gov (United States)

    Vidotto, O; McElwain, T F; Machado, R Z; Perryman, L E; Suarez, C E; Palmer, G H

    1995-12-01

    Rhoptries are involved in host cell invasion and rhoptry polypeptides, including the Babesia bigemina rhoptry-associated protein-1 (RAP-1), are targets for protective immune responses. Polyclonal antisera produced against isolated rhoptries is directed predominantly against RAP-1 and reacts with both the merozoite and the membrane of parasitized erythrocytes. To determine whether these B cell epitopes associated with the parasitized erythrocyte are derived from RAP-1 or, alternatively, from previously undetected merozoite polypeptides, monoclonal antibodies (mAbs) were generated from mice immunized with rhoptries isolated from the JG-29 clone of the Mexico strain. The anti-RAP-1 mAbs bound only merozoites in a punctate immunofluorescence pattern. A second group of four mAbs, none of which were reactive with RAP-1, bound the parasitized erythrocyte. Two of these latter mAbs, 64/44.17.3 and 64/05.7.2, reacted only with parasitized erythrocytes that had been permeabilized. MAb 64/44.17.3 bound a 54-kDa merozoite polypeptide while 64/05.7.2 bound a > or = 225-kDa merozoite polypeptide. MAbs 64/32.8.5 and 64/38.5.3 recognized epitopes on 17.5- and 76-kDa polypeptides exposed on the external surface of intact parasitized erythrocytes. The results indicate that the identified RAP-1 epitopes are not associated with the erythrocyte cytoskeleton or membrane and that anti-RAP-1 immunity is most likely generated against the free merozoite. All new mAbs reacted with every B. bigemina strain tested (Mexico, Puerto Rico, St. Croix, Texcoco, Jaboticabal). The conservation of RAP-1 epitopes among these strains supports the continued testing of RAP-1 as a vaccine component. In addition, the identification of epitopes expressed on the surface of erythrocytes infected with all five strains provides new candidate immunogens.

  3. The Analysis of B-Cell Epitopes of Influenza Virus Hemagglutinin.

    Science.gov (United States)

    Shcherbinin, D N; Alekseeva, S V; Shmarov, M M; Smirnov, Yu A; Naroditskiy, B S; Gintsburg, A L

    2016-01-01

    Vaccination has been successfully used to prevent influenza for a long time. Influenza virus hemagglutinin (HA), which induces a humoral immune response in humans and protection against the flu, is the main antigenic component of modern influenza vaccines. However, new seasonal and pandemic influenza virus variants with altered structures of HA occasionally occur. This allows the pathogen to avoid neutralization with antibodies produced in response to previous vaccination. Development of a vaccine with the new variants of HA acting as antigens takes a long time. Therefore, during an epidemic, it is important to have passive immunization agents to prevent and treat influenza, which can be monoclonal or single-domain antibodies with universal specificity (broad-spectrum agents). We considered antibodies to conserved epitopes of influenza virus antigens as universal ones. In this paper, we tried to characterize the main B-cell epitopes of hemagglutinin and analyze our own and literature data on broadly neutralizing antibodies. We conducted a computer analysis of the best known conformational epitopes of influenza virus HAs using materials of different databases. The analysis showed that the core of the HA molecule, whose antibodies demonstrate pronounced heterosubtypic activity, can be used as a target for the search for and development of broad-spectrum antibodies to the influenza virus. PMID:27099781

  4. B-Pred, a structure based B-cell epitopes prediction server.

    Science.gov (United States)

    Giacò, Luciano; Amicosante, Massimo; Fraziano, Maurizio; Gherardini, Pier Federico; Ausiello, Gabriele; Helmer-Citterich, Manuela; Colizzi, Vittorio; Cabibbo, Andrea

    2012-01-01

    The ability to predict immunogenic regions in selected proteins by in-silico methods has broad implications, such as allowing a quick selection of potential reagents to be used as diagnostics, vaccines, immunotherapeutics, or research tools in several branches of biological and biotechnological research. However, the prediction of antibody target sites in proteins using computational methodologies has proven to be a highly challenging task, which is likely due to the somewhat elusive nature of B-cell epitopes. This paper proposes a web-based platform for scoring potential immunological reagents based on the structures or 3D models of the proteins of interest. The method scores a protein's peptides set, which is derived from a sliding window, based on the average solvent exposure, with a filter on the average local model quality for each peptide. The platform was validated on a custom-assembled database of 1336 experimentally determined epitopes from 106 proteins for which a reliable 3D model could be obtained through standard modeling techniques. Despite showing poor sensitivity, this method can achieve a specificity of 0.70 and a positive predictive value of 0.29 by combining these two simple parameters. These values are slightly higher than those obtained with other established sequence-based or structure-based methods that have been evaluated using the same epitopes dataset. This method is implemented in a web server called B-Pred, which is accessible at http://immuno.bio.uniroma2.it/bpred. The server contains a number of original features that allow users to perform personalized reagent searches by manipulating the sliding window's width and sliding step, changing the exposure and model quality thresholds, and running sequential queries with different parameters. The B-Pred server should assist experimentalists in the rational selection of epitope antigens for a wide range of applications. PMID:22888263

  5. Conserved B-cell epitopes among human bocavirus species indicate potential diagnostic targets.

    Directory of Open Access Journals (Sweden)

    Zhuo Zhou

    Full Text Available BACKGROUND: Human bocavirus species 1-4 (HBoV1-4 have been associated with respiratory and enteric infections in children. However, the immunological mechanisms in response to HBoV infections are not fully understood. Though previous studies have shown cross-reactivities between HBoV species, the epitopes responsible for this phenomenon remain unknown. In this study, we used genomic and immunologic approaches to identify the reactive epitopes conserved across multiple HBoV species and explored their potential as the basis of a novel diagnostic test for HBoVs. METHODOLOGY/PRINCIPAL FINDINGS: We generated HBoV1-3 VP2 gene fragment phage display libraries (GFPDLs and used these libraries to analyze mouse antisera against VP2 protein of HBoV1, 2, and 3, and human sera positive for HBoVs. Using this approach, we mapped four epitope clusters of HBoVs and identified two immunodominant peptides--P1 (¹MSDTDIQDQQPDTVDAPQNT²⁰, and P2 (¹⁶²EHAYPNASHPWDEDVMPDL¹⁸⁰--that are conserved among HBoV1-4. To confirm epitope immunogenicity, we immunized mice with the immunodominant P1 and P2 peptides identified in our screen and found that they elicited high titer antibodies in mice. These two antibodies could only recognize the VP2 of HBoV 1-4 in Western blot assays, rather than those of the two other parvoviruses human parvovirus B19 and human parvovirus 4 (PARV4. Based on our findings, we evaluated epitope-based peptide-IgM ELISAs as potential diagnostic tools for HBoVs IgM antibodies. We found that the P1+P2-IgM ELISA showed a higher sensitivity and specificity in HBoVs IgM detection than the assays using a single peptide. CONCLUSIONS/SIGNIFICANCE: The identification of the conserved B-cell epitopes among human bocavirus species contributes to our understanding of immunological cross-reactivities of HBoVs, and provides important insights for the development of HBoV diagnostic tools.

  6. Construction and characterization of an HCV-derived multi-epitope peptide antigen containing B-cell HVR1 mimotopes and T-cell conserved epitopes

    Institute of Scientific and Technical Information of China (English)

    GAO; Jun; GONG; Yuping; ZHAO; Ping; ZHU; Qing; YANG; Xiaoping; QI; Zhongtian

    2006-01-01

    Hepatitis C (HCV) genome is highly variable, particularly in the hypervariable region 1(HVR1) of its E2 envelope gene. The variability of HCV genome has been a major obstacle for developing HCV vaccines. Due to B-cell HVR1 mimotopes mimicking the antigenicity of natural HVR1 epitopes and some T-cell epitopes from the consensus sequence of HCV genes conserving among the different HCV genotypes, we synthesized an minigene of HCV-derived multi-epitope peptide antigen (CMEP), which contains 9 B-cell HVR1 mimotopes in E2, 2 conserved CTL epitopes in C, 1conserved CTL epitope in NS3 and 1 conserved Th epitope in NS3. This minigene was cloned into a GST expression vector to generate a fusion protein GST-CMER The immunogenic properties of CEMP were characterized by HCV infected patients' sera, and found that the reactivity frequency reached 75%. The cross reactivity of anti-CEMP antibody with different natural HVR1 variants was up to 90%. Meanwhile, we constructed an HCV DNA vaccine candidate, plasmid pVAX1.0-st-CMEP carrying the recombinant gene (st) of a secretion signal peptide and PADRE universal Th cell epitope sequence in front of the CMEP minigene. Immunization of rabbits with pVAX1.0-st-CMEP resulted in the production of antibody, which was of the same cross reactivity as the fusion protein GST-CMEP.Our findings indicate that the HCV-derived multi-epitope peptide antigen in some degree possessed the characteristics of neutralizing HCV epitopes, and would be of the value as a candidate for the development of HCV vaccines.

  7. Multiple linear B-cell epitopes of classical swine fever virus glycoprotein E2 expressed in E.coli as multiple epitope vaccine induces a protective immune response

    Directory of Open Access Journals (Sweden)

    Wei Jian-Chao

    2011-07-01

    Full Text Available Abstract Classical swine fever is a highly contagious disease of swine caused by classical swine fever virus, an OIE list A pathogen. Epitope-based vaccines is one of the current focuses in the development of new vaccines against classical swine fever virus (CSFV. Two B-cell linear epitopes rE2-ba from the E2 glycoprotein of CSFV, rE2-a (CFRREKPFPHRMDCVTTTVENED, aa844-865 and rE2-b (CKEDYRYAISSTNEIGLLGAGGLT, aa693-716, were constructed and heterologously expressed in Escherichia coli as multiple epitope vaccine. Fifteen 6-week-old specified-pathogen-free (SPF piglets were intramuscularly immunized with epitopes twice at 2-week intervals. All epitope-vaccinated pigs could mount an anamnestic response after booster vaccination with neutralizing antibody titers ranging from 1:16 to 1:256. At this time, the pigs were subjected to challenge infection with a dose of 1 × 106 TCID50 virulent CSFV strain. After challenge infection, all of the rE2-ba-immunized pigs were alive and without symptoms or signs of CSF. In contrast, the control pigs continuously exhibited signs of CSF and had to be euthanized because of severe clinical symptoms at 5 days post challenge infection. The data from in vivo experiments shown that the multiple epitope rE2-ba shown a greater protection (similar to that of HCLV vaccine than that of mono-epitope peptide(rE2-a or rE2-b. Therefore, The results demonstrated that this multiple epitope peptide expressed in a prokaryotic system can be used as a potential DIVA (differentiating infected from vaccinated animals vaccine. The E.coli-expressed E2 multiple B-cell linear epitopes retains correct immunogenicity and is able to induce a protective immune response against CSFV infection.

  8. Mechanisms, safety and efficacy of a B cell epitope-based vaccine for immunotherapy of grass pollen allergy

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    Petra Zieglmayer

    2016-09-01

    Conclusion: The B cell epitope-based recombinant grass pollen allergy vaccine BM32 is well tolerated and few doses are sufficient to suppress immediate allergic reactions as well as allergen-specific T cell responses via a selective induction of allergen-specific IgG antibodies. (ClinicalTrials.gov number, NCT01445002.

  9. Identification of critical residues of linear B cell epitope on Goodpasture autoantigen.

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    Xiao-yu Jia

    Full Text Available The autoantigen of anti-glomerular basement membrane (GBM disease has been identified as the non-collagenous domain 1 of α3 chain of type IV collagen, α3(IVNC1. Our previous study revealed a peptide on α3(IVNC1 as a major linear epitope for B cells and potentially nephrogenic, designated as P14 (α3129-150. This peptide has also been proven to be the epitope of auto-reactive T cells in anti-GBM patients. This study was aimed to further characterize the critical motif of P14.16 patients with anti-GBM disease and positive anti-P14 antibodies were enrolled. A set of truncated and alanine substituted peptides derived from P14 were synthesized. Circulating antibodies against the peptides were detected by enzyme linked immunosorbent assay (ELISA.We found that all sera with anti-P14 antibodies reacted with the 13-mer sequence in the C-terminus of P14 (P14c exclusively. The level of antibodies against P14 was highly correlated with the level of antibodies against P14c (r=0.970, P<0.001. P14c was the core immunogenic region and the amino acid sequence (ISLWKGFSFIMFT was highly hydrophobic. Each amino acid residue in P14c was sequentially replaced by alanine. Three residues of glycine142, phenylalanine143, and phenylalanine145 were identified crucial for antibody binding based on the remarkable decline (P<0.001 of antibody reaction after each residue replacement.We defined GFxF (α3142, 143,145 as the critical motif of P14. It may provide some clues for understanding the etiology of anti-GBM disease.

  10. On the Meaning of Affinity Limits in B-Cell Epitope Prediction for Antipeptide Antibody-Mediated Immunity

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    Salvador Eugenio C. Caoili

    2012-01-01

    Full Text Available B-cell epitope prediction aims to aid the design of peptide-based immunogens (e.g., vaccines for eliciting antipeptide antibodies that protect against disease, but such antibodies fail to confer protection and even promote disease if they bind with low affinity. Hence, the Immune Epitope Database (IEDB was searched to obtain published thermodynamic and kinetic data on binding interactions of antipeptide antibodies. The data suggest that the affinity of the antibodies for their immunizing peptides appears to be limited in a manner consistent with previously proposed kinetic constraints on affinity maturation in vivo and that cross-reaction of the antibodies with proteins tends to occur with lower affinity than the corresponding reaction of the antibodies with their immunizing peptides. These observations better inform B-cell epitope prediction to avoid overestimating the affinity for both active and passive immunization; whereas active immunization is subject to limitations of affinity maturation in vivo and of the capacity to accumulate endogenous antibodies, passive immunization may transcend such limitations, possibly with the aid of artificial affinity-selection processes and of protein engineering. Additionally, protein disorder warrants further investigation as a possible supplementary criterion for B-cell epitope prediction, where such disorder obviates thermodynamically unfavorable protein structural adjustments in cross-reactions between antipeptide antibodies and proteins.

  11. Computational approach for predicting the conserved B-cell epitopes of hemagglutinin H7 subtype influenza virus

    Science.gov (United States)

    Wang, Xiangyu; Sun, Qi; Ye, Zhonghua; Hua, Ying; Shao, Na; Du, Yanli; Zhang, Qiwei; Wan, Chengsong

    2016-01-01

    An avian-origin influenza H7N9 virus epidemic occurred in China in 2013–2014, in which >422 infected people suffered from pneumonia, respiratory distress syndrome and septic shock. H7N9 viruses belong to the H7 subtype of avian-origin influenza viruses (AIV-H7). Hemagglutinin (HA) is a vital membrane protein of AIV that has an important role in host recognition and infection. The epitopes of HA are significant determinants of the regularity of epidemic and viral mutation and recombination mechanisms. The present study aimed to predict the conserved B-cell epitopes of AIV-H7 HA using a bioinformatics approach, including the three most effective epitope prediction softwares available online: Artificial Neural Network based B-cell Epitope Prediction (ABCpred), B-cell Epitope Prediction (BepiPred) and Linear B-cell Epitope Prediction (LBtope). A total of 24 strains of Euro-Asiatic AIV-H7 that had been associated with a serious poultry pandemic or had infected humans in the past 30 years were selected to identify the conserved regions of HA. Sequences were obtained from the National Center for Biotechnology Information and Global Initiative on Sharing Avian Influenza Data databases. Using a combination of software prediction and sequence comparisons, the conserved epitopes of AIV-H7 were predicted and clarified. A total of five conserved epitopes [amino acids (aa) 37–52, 131–142, 215–234, 465–484 and 487–505] with a suitable length, high antigenicity and minimal variation were predicted and confirmed. Each obtained a score of >0.80 in ABCpred, 60% in LBtope and a level of 0.35 in Bepipred. In addition, a representative amino acid change (glutamine235-to-leucine235) in the HA protein of the 2013 AIV-H7N9 was discovered. The strategy adopted in the present study may have profound implications on the rapid diagnosis and control of infectious disease caused by H7N9 viruses, as well as by other virulent viruses, such as the Ebola virus.

  12. Characterization of a Partially Protective B-cell Epitope within the 62 kDa Antigen of Schistosoma japonicun

    Institute of Scientific and Technical Information of China (English)

    Lei ZHANG; Xue YANG; Yanfen YANG; Jiaqing ZHAO; Jianghua YANG; Feng LIU; Zhaosong ZHANG; Guanling WU; Chuan SU

    2007-01-01

    Approximately 200 million people worldwide currently suffer from schistosomiasis, one of the most important human parasitic diseases. Although an established infection can be treated with anthelminthics and praziquantel, vaccination would be the ideal method for integral control of schistosomiasis. Schistosoma mansoni IrⅤ-5, recommended as a vaccine candidate by the World Health Organization/Special Programme for Research and Training in Tropical Diseases, produced high protection in animal models. We therefore focused on its homolog, the Schistosoma japonicum 62 kDa antigen, and analyzed it using B cell/antibodyrelated databases and analysis tools for the prediction of B-cell epitopes. Epitope B3 was selected for further investigation. Experiments using a murine model indicated that mice immunized with B3 resulted in lymphocytes proliferation and produced high levels of specific immunoglobulin G and G1, but did not produce impressive cytokines. The vaccination showed partial protective immunity, measured by worm burden and anti-fecundity immunity against S. japonicum. These results indicated that the epitope B3 from S. japonicum 62-kDa antigen might act as a candidate immunogen for future epitope vaccine investigation.

  13. CD20 mutations involving the rituximab epitope are rare in diffuse large B-cell lymphomas and are not a significant cause of R-CHOP failure

    OpenAIRE

    Johnson, Nathalie A.; Leach, Stephen; Woolcock, Bruce; deLeeuw, Ronald J; Bashashati, Ali; Sehn, Laurie H.; Connors, Joseph M; Chhanabhai, Mukesh; Brooks-Wilson, Angela; Gascoyne, Randy D.

    2009-01-01

    The findings of this study indicate that CD20 mutations nvolving the rituximab epitope are rare in both de novo and relapsed diffuse large B-cell lymphoma, and do not represent a significant cause of R-CHOP resistance.

  14. Full protection of swine against foot-and-mouth disease by a bivalent B-cell epitope dendrimer peptide.

    Science.gov (United States)

    Blanco, Esther; Guerra, Beatriz; de la Torre, Beatriz G; Defaus, Sira; Dekker, Aldo; Andreu, David; Sobrino, Francisco

    2016-05-01

    Foot-and-mouth disease virus (FMDV) causes a highly contagious disease of cloven-hoofed animals. We have reported (Cubillos et al., 2008) that a synthetic dendrimeric peptide consisting of four copies of a B-cell epitope [VP1(136-154)] linked through thioether bonds to a T-cell epitope [3A(21-35)] of FMDV [B4T(thi)] elicits potent B- and T-cell specific responses and confers solid protection in pigs to type C FMDV challenge. Herein we show that downsized versions of this peptide bearing two copies of a B-cell epitope from a type O isolate and using thioether [B2T(thi)] or maleimide [B2T(mal)] conjugation chemistries for their synthesis elicited in swine similar or higher B and T-cell specific responses than tetravalent B4T(thi). Moreover, while partial protection was observed in animals immunized with B4T(thi) (60%) and B2T(thi) (80%), B2T(mal) conferred full (100%) protection against FMDV challenge, associated to high levels of circulating IgG2 and mucosal IgGA, and entirely prevented virus shedding. Interestingly, B2T(mal) is also the most advantageous option in terms of synthetic practicality. Taken together, the results reported here point out to B2T(mal) as a highly valuable, cost-effective FMDV candidate vaccine. PMID:26956030

  15. Multiple B-cell epitope vaccine induces a Staphylococcus enterotoxin B-specific IgG1 protective response against MRSA infection.

    Science.gov (United States)

    Zhao, Zhuo; Sun, He-Qiang; Wei, Shan-Shan; Li, Bin; Feng, Qiang; Zhu, Jiang; Zeng, Hao; Zou, Quan-Ming; Wu, Chao

    2015-01-01

    No vaccine against methicillin-resistant Staphylococcus aureus (MRSA) has been currently approved for use in humans. Staphylococcus enterotoxin B (SEB) is one of the most potent MRSA exotoxins. In the present study, we evaluated the efficacy and immunologic mechanisms of an SEB multiple B-cell epitope vaccine against MRSA infection. Synthetic overlapping peptide ELISA identified three novel B-cell immunodominant SEB epitopes (in addition to those previously known): SEB31-48, SEB133-150, and SEB193-210. Six B-cell immunodominant epitopes (amino acid residues 31-48, 97-114, 133-150, 193-210, 205-222, and 247-261) were sufficient to induce robust IgG1/IgG2b-specific protective responses against MRSA infection. Therefore, we constructed a recombinant MRSA SEB-specific multiple B-cell epitope vaccine Polypeptides by combining the six SEB immunodominant epitopes and demonstrated its ability to induce a robust SEB-specific IgG1 response to MRSA, as well as a Th2-directing isotype response. Moreover, Polypeptides-induced antisera stimulated synergetic opsonophagocytosis killing of MRSA. Most importantly, Polypeptides was more effective at clearing the bacteria in MRSA-infected mice than the whole SEB antigen, and was able to successfully protect mice from infection by various clinical MRSA isolates. Altogether, these results support further evaluation of the SEB multiple B-cell epitope-vaccine to address MRSA infection in humans.

  16. Identification and fine mapping of a linear B cell epitope of human vimentin

    DEFF Research Database (Denmark)

    Dam, Catharina Essendrup; Houen, Gunnar; Hansen, Paul R.;

    2014-01-01

    Knowledge about antibody-antigen interactions is important for the understanding of the immune system mechanisms and for supporting development of drugs and biomarkers. A tool for identification of these antigenic epitopes of specific antibodies is epitope mapping. In this study, a modified enzym...... that charged amino acids are essential for antibody reactivity and that the vimentin antibody is dependent on side-chain interactions in combination with backbone interactions....

  17. Identification of strain-specific B-cell epitopes in Trypanosoma cruzi using genome-scale epitope prediction and high-throughput immunoscreening with peptide arrays.

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    Tiago Antônio de Oliveira Mendes

    Full Text Available BACKGROUND: The factors influencing variation in the clinical forms of Chagas disease have not been elucidated; however, it is likely that the genetics of both the host and the parasite are involved. Several studies have attempted to correlate the T. cruzi strains involved in infection with the clinical forms of the disease by using hemoculture and/or PCR-based genotyping of parasites from infected human tissues. However, both techniques have limitations that hamper the analysis of large numbers of samples. The goal of this work was to identify conserved and polymorphic linear B-cell epitopes of T. cruzi that could be used for serodiagnosis and serotyping of Chagas disease using ELISA. METHODOLOGY: By performing B-cell epitope prediction on proteins derived from pair of alleles of the hybrid CL Brener genome, we have identified conserved and polymorphic epitopes in the two CL Brener haplotypes. The rationale underlying this strategy is that, because CL Brener is a recent hybrid between the TcII and TcIII DTUs (discrete typing units, it is likely that polymorphic epitopes in pairs of alleles could also be polymorphic in the parental genotypes. We excluded sequences that are also present in the Leishmania major, L. infantum, L. braziliensis and T. brucei genomes to minimize the chance of cross-reactivity. A peptide array containing 150 peptides was covalently linked to a cellulose membrane, and the reactivity of the peptides was tested using sera from C57BL/6 mice chronically infected with the Colombiana (TcI and CL Brener (TcVI clones and Y (TcII strain. FINDINGS AND CONCLUSIONS: A total of 36 peptides were considered reactive, and the cross-reactivity among the strains is in agreement with the evolutionary origin of the different T. cruzi DTUs. Four peptides were tested against a panel of chagasic patients using ELISA. A conserved peptide showed 95.8% sensitivity, 88.5% specificity, and 92.7% accuracy for the identification of T. cruzi in

  18. Pep-3D-Search: a method for B-cell epitope prediction based on mimotope analysis

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    Wang Yan

    2008-12-01

    Full Text Available Abstract Background The prediction of conformational B-cell epitopes is one of the most important goals in immunoinformatics. The solution to this problem, even if approximate, would help in designing experiments to precisely map the residues of interaction between an antigen and an antibody. Consequently, this area of research has received considerable attention from immunologists, structural biologists and computational biologists. Phage-displayed random peptide libraries are powerful tools used to obtain mimotopes that are selected by binding to a given monoclonal antibody (mAb in a similar way to the native epitope. These mimotopes can be considered as functional epitope mimics. Mimotope analysis based methods can predict not only linear but also conformational epitopes and this has been the focus of much research in recent years. Though some algorithms based on mimotope analysis have been proposed, the precise localization of the interaction site mimicked by the mimotopes is still a challenging task. Results In this study, we propose a method for B-cell epitope prediction based on mimotope analysis called Pep-3D-Search. Given the 3D structure of an antigen and a set of mimotopes (or a motif sequence derived from the set of mimotopes, Pep-3D-Search can be used in two modes: mimotope or motif. To evaluate the performance of Pep-3D-Search to predict epitopes from a set of mimotopes, 10 epitopes defined by crystallography were compared with the predicted results from a Pep-3D-Search: the average Matthews correlation oefficient (MCC, sensitivity and precision were 0.1758, 0.3642 and 0.6948. Compared with other available prediction algorithms, Pep-3D-Search showed comparable MCC, specificity and precision, and could provide novel, rational results. To verify the capability of Pep-3D-Search to align a motif sequence to a 3D structure for predicting epitopes, 6 test cases were used. The predictive performance of Pep-3D-Search was demonstrated to be

  19. A Nanoparticle Based Sp17 Peptide Vaccine Exposes New Immuno-Dominant and Species Cross-reactive B Cell Epitopes

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    Sue D. Xiang

    2015-10-01

    Full Text Available Sperm protein antigen 17 (Sp17, expressed in primary as well as in metastatic lesions in >83% of patients with ovarian cancer, is a promising ovarian cancer vaccine candidate. Herein we describe the formulation of nanoparticle based vaccines based on human Sp17 (hSp17 sequence derived peptides, and map the immuno-dominant T cell and antibody epitopes induced using such formulations. The primary T and B cell immuno-dominant region within Sp17 was found to be the same when using biocompatible nanoparticle carriers or the conventional “mix-in” pro-inflammatory adjuvant CpG, both mapping to amino acids (aa 111–142. However, delivery of hSp17111–142 as a nanoparticle conjugate promoted a number of new properties, changing the dominant antibody isotype induced from IgG2a to IgG1 and the fine specificity of the B cell epitopes within hSp17111–142, from an immuno-dominant region 134–142 aa for CpG, to region 121–138 aa for nanoparticles. Associated with this change in specificity was a substantial increase in antibody cross-reactivity between mouse and human Sp17. These results indicate conjugation of antigen to nanoparticles can have major effects on fine antigen specificity, which surprisingly could be beneficially used to increase the cross-reactivity of antibody responses.

  20. A Nanoparticle Based Sp17 Peptide Vaccine Exposes New Immuno-Dominant and Species Cross-reactive B Cell Epitopes.

    Science.gov (United States)

    Xiang, Sue D; Gao, Qian; Wilson, Kirsty L; Heyerick, Arne; Plebanski, Magdalena

    2015-01-01

    Sperm protein antigen 17 (Sp17), expressed in primary as well as in metastatic lesions in >83% of patients with ovarian cancer, is a promising ovarian cancer vaccine candidate. Herein we describe the formulation of nanoparticle based vaccines based on human Sp17 (hSp17) sequence derived peptides, and map the immuno-dominant T cell and antibody epitopes induced using such formulations. The primary T and B cell immuno-dominant region within Sp17 was found to be the same when using biocompatible nanoparticle carriers or the conventional "mix-in" pro-inflammatory adjuvant CpG, both mapping to amino acids (aa) 111-142. However, delivery of hSp17111-142 as a nanoparticle conjugate promoted a number of new properties, changing the dominant antibody isotype induced from IgG2a to IgG1 and the fine specificity of the B cell epitopes within hSp17111-142, from an immuno-dominant region 134-142 aa for CpG, to region 121-138 aa for nanoparticles. Associated with this change in specificity was a substantial increase in antibody cross-reactivity between mouse and human Sp17. These results indicate conjugation of antigen to nanoparticles can have major effects on fine antigen specificity, which surprisingly could be beneficially used to increase the cross-reactivity of antibody responses. PMID:26529027

  1. Identification of protective B-cell epitopes of Atroxlysin-I: A metalloproteinase from Bothrops atrox snake venom.

    Science.gov (United States)

    Schneider, F S; de Almeida Lima, S; Reis de Ávila, G; Castro, K L; Guerra-Duarte, C; Sanchez, E F; Nguyen, C; Granier, C; Molina, F; Chávez-Olortegui, C

    2016-03-29

    Atroxlysin-I (Atr-I) is a hemorrhagic snake venom metalloproteinase (SVMP) from Bothrops atrox venom, the snake responsible for the majority of bites in the north region of South America. SVMPs like Atr-I produce toxic effects in victims including hemorrhage, inflammation, necrosis and blood coagulation deficiency. Mapping of B-cell epitopes in SVMPs might result in the identification of non-toxic molecules capable of inducing neutralizing antibodies and improving the anti-venom therapy. Here, using the SPOT-synthesis technique we identified two epitopes located in the N-ter region of Atr-I (AtrEp1-(22)YNGNSDKIRRRIHQM(36); and AtrEp2-(55)GVEIWSNKDLINVQ(68)). Based on the sequence of AtrEp1 and AtrEp2 a third peptide named Atr-I biepitope (AtrBiEp) was designed and synthesized ((23)NGNSDKIRRRIH(34)GG(55)GVEIWSNKDLINVQ(68)). AtrBiEp was used to immunize BALB/c mice. Anti-AtrBiEp serum cross-reacted against Atr-I in western blot and was able to fully neutralize the hemorrhagic activity of Atr-I. Our results provide a rational basis for the identification of neutralizing epitopes on Atr-I snake venom toxin and show that the use of synthetic peptides could improve the generation of immuno-therapeutics. PMID:26917009

  2. Identification of a highly antigenic linear B cell epitope within Plasmodium vivax apical membrane antigen 1 (AMA-1.

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    Lilian Lacerda Bueno

    Full Text Available Apical membrane antigen 1 (AMA-1 is considered to be a major candidate antigen for a malaria vaccine. Previous immunoepidemiological studies of naturally acquired immunity to Plasmodium vivax AMA-1 (PvAMA-1 have shown a higher prevalence of specific antibodies to domain II (DII of AMA-1. In the present study, we confirmed that specific antibody responses from naturally infected individuals were highly reactive to both full-length AMA-1 and DII. Also, we demonstrated a strong association between AMA-1 and DII IgG and IgG subclass responses. We analyzed the primary sequence of PvAMA-1 for B cell linear epitopes co-occurring with intrinsically unstructured/disordered regions (IURs. The B cell epitope comprising the amino acid sequence 290-307 of PvAMA-1 (SASDQPTQYEEEMTDYQK, with the highest prediction scores, was identified in domain II and further selected for chemical synthesis and immunological testing. The antigenicity of the synthetic peptide was identified by serological analysis using sera from P. vivax-infected individuals who were knowingly reactive to the PvAMA-1 ectodomain only, domain II only, or reactive to both antigens. Although the synthetic peptide was recognized by all serum samples specific to domain II, serum with reactivity only to the full-length protein presented 58.3% positivity. Moreover, IgG reactivity against PvAMA-1 and domain II after depletion of specific synthetic peptide antibodies was reduced by 18% and 33% (P = 0.0001 for both, respectively. These results suggest that the linear epitope SASDQPTQYEEEMTDYQK is highly antigenic during natural human infections and is an important antigenic region of the domain II of PvAMA-1, suggesting its possible future use in pre-clinical studies.

  3. Identification of continuous human B-cell epitopes in the VP35, VP40, nucleoprotein and glycoprotein of Ebola virus.

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    Pierre Becquart

    Full Text Available Ebola virus (EBOV is a highly virulent human pathogen. Recovery of infected patients is associated with efficient EBOV-specific immunoglobulin G (IgG responses, whereas fatal outcome is associated with defective humoral immunity. As B-cell epitopes on EBOV are poorly defined, we sought to identify specific epitopes in four EBOV proteins (Glycoprotein (GP, Nucleoprotein (NP, and matrix Viral Protein (VP40 and VP35. For the first time, we tested EBOV IgG+ sera from asymptomatic individuals and symptomatic Gabonese survivors, collected during the early humoral response (seven days after the end of symptoms and the late memory phase (7-12 years post-infection. We also tested sera from EBOV-seropositive patients who had never had clinical signs of hemorrhagic fever or who lived in non-epidemic areas (asymptomatic subjects. We found that serum from asymptomatic individuals was more strongly reactive to VP40 peptides than to GP, NP or VP35. Interestingly, anti-EBOV IgG from asymptomatic patients targeted three immunodominant regions of VP40 reported to play a crucial role in virus assembly and budding. In contrast, serum from most survivors of the three outbreaks, collected a few days after the end of symptoms, reacted mainly with GP peptides. However, in asymptomatic subjects the longest immunodominant domains were identified in GP, and analysis of the GP crystal structure revealed that these domains covered a larger surface area of the chalice bowl formed by three GP1 subunits. The B-cell epitopes we identified in the EBOV VP35, VP40, NP and GP proteins may represent important tools for understanding the humoral response to this virus and for developing new antibody-based therapeutics or detection methods.

  4. Characterisation of a protective linear B cell epitope against feline parvoviruses

    NARCIS (Netherlands)

    Langeveld, J.P.; Martinez Torrecuadrada, J.; Boshuizen, R.S.; Meloen, R.H.; Ignacio Casal, J.

    2001-01-01

    Monoclonal antibody 3C9 was the starting material in the definition of the epitope that led to the synthesis of the first efficient peptide vaccine against a viral disease (canine parvovirus) in the natural host (dog). In this report, we have analysed the specificity of the antibody at the single am

  5. Identification of a human immunodominant B-cell epitope within the immunoglobulin A1 protease of Streptococcus pneumoniae

    Directory of Open Access Journals (Sweden)

    Felici Franco

    2007-12-01

    Full Text Available Abstract Background The IgA1 protease of Streptococcus pneumoniae is a proteolytic enzyme that specifically cleaves the hinge regions of human IgA1, which dominates most mucosal surfaces and is the major IgA isotype in serum. This protease is expressed in all of the known pneumococcal strains and plays a major role in pathogen's resistance to the host immune response. The present work was focused at identifying the immunodominant regions of pneumococcal IgA1 protease recognized by the human antibody response. Results An antigenic sequence corresponding to amino acids 420–457 (epiA of the iga gene product was identified by screening a pneumococcal phage display library with patients' sera. The epiA peptide is conserved in all pneumococci and in two out of three S. mitis strains, while it is not present in other oral streptococci so far sequenced. This epitope was specifically recognized by antibodies present in sera from 90% of healthy adults, thus representing an important target of the humoral response to S. pneumoniae and S. mitis infection. Moreover, sera from 68% of children less than 4 years old reacted with the epiA peptide, indicating that the human immune response against streptococcal antigens occurs during childhood. Conclusion The broad and specific recognition of the epiA polypeptide by human sera demonstrate that the pneumococcal IgA1 protease contains an immunodominant B-cell epitope. The use of phage display libraries to identify microbe or disease-specific antigens recognized by human sera is a valuable approach to epitope discovery.

  6. In silico Identification and Validation of a Linear and Naturally Immunogenic B-Cell Epitope of the Plasmodium vivax Malaria Vaccine Candidate Merozoite Surface Protein-9

    Science.gov (United States)

    Rodrigues-da-Silva, Rodrigo Nunes; Martins da Silva, João Hermínio; Singh, Balwan; Jiang, Jianlin; Meyer, Esmeralda V. S.; Santos, Fátima; Banic, Dalma Maria; Moreno, Alberto; Galinski, Mary R.; Oliveira-Ferreira, Joseli; Lima-Junior, Josué da Costa

    2016-01-01

    Synthetic peptide vaccines provide the advantages of safety, stability and low cost. The success of this approach is highly dependent on efficient epitope identification and synthetic strategies for efficacious delivery. In malaria, the Merozoite Surface Protein-9 of Plasmodium vivax (PvMSP9) has been considered a vaccine candidate based on the evidence that specific antibodies were able to inhibit merozoite invasion and recombinant proteins were highly immunogenic in mice and humans. However the identities of linear B-cell epitopes within PvMSP9 as targets of functional antibodies remain undefined. We used several publicly-available algorithms for in silico analyses and prediction of relevant B cell epitopes within PMSP9. We show that the tandem repeat sequence EAAPENAEPVHENA (PvMSP9E795-A808) present at the C-terminal region is a promising target for antibodies, given its high combined score to be a linear epitope and located in a putative intrinsically unstructured region of the native protein. To confirm the predictive value of the computational approach, plasma samples from 545 naturally exposed individuals were screened for IgG reactivity against the recombinant PvMSP9-RIRII729-972 and a synthetic peptide representing the predicted B cell epitope PvMSP9E795-A808. 316 individuals (58%) were responders to the full repetitive region PvMSP9-RIRII, of which 177 (56%) also presented total IgG reactivity against the synthetic peptide, confirming it validity as a B cell epitope. The reactivity indexes of anti-PvMSP9-RIRII and anti-PvMSP9E795-A808 antibodies were correlated. Interestingly, a potential role in the acquisition of protective immunity was associated with the linear epitope, since the IgG1 subclass against PvMSP9E795-A808 was the prevalent subclass and this directly correlated with time elapsed since the last malaria episode; however this was not observed in the antibody responses against the full PvMSP9-RIRII. In conclusion, our findings identified and

  7. Identification of two linear B-cell epitopes from West Nile virus NS1 by screening a phage-displayed random peptide library

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    Qin Yong-Li

    2011-07-01

    Full Text Available Abstract Background The West Nile virus (WNV nonstructural protein 1 (NS1 is an important antigenic protein that elicits protective antibody responses in animals and can be used for the serological diagnosis of WNV infection. Although previous work has demonstrated the vital role of WNV NS1-specific antibody responses, the specific epitopes in the NS1 have not been identified. Results The present study describes the identification of two linear B-cell epitopes in WNV NS1 through screening a phage-displayed random 12-mer peptide library with two monoclonal antibodies (mAbs 3C7 and 4D1 that directed against the NS1. The mAbs 3C7 and 4D1 recognized phages displaying peptides with the consensus motifs LTATTEK and VVDGPETKEC, respectively. Exact sequences of both motifs were found in the NS1 (895LTATTEK901 and 925VVDGPETKEC934. Further identification of the displayed B cell epitopes were conducted using a set of truncated peptides expressed as MBP fusion proteins. The data indicated that 896TATTEK901 and925VVDGPETKEC934 are minimal determinants of the linear B cell epitopes recognized by the mAbs 3C7 and 4D1, respectively. Antibodies present in the serum of WNV-positive horses recognized the minimal linear epitopes in Western blot analysis, indicating that the two peptides are antigenic in horses during infection. Furthermore, we found that the epitope recognized by 3C7 is conserved only among WNV strains, whereas the epitope recognized by 4D1 is a common motif shared among WNV and other members of Japanese encephalitis virus (JEV serocomplex. Conclusions We identified TATTEK and VVDGPETKEC as NS1-specific linear B-cell epitopes recognized by the mAbs 3C7 and 4D1, respectively. The knowledge and reagents generated in this study may have potential applications in differential diagnosis and the development of epitope-based marker vaccines against WNV and other viruses of JEV serocomplex.

  8. Large-scale analysis of B-cell epitopes on influenza virus hemagglutinin - implications for cross-reactivity of neutralizing antibodies

    Directory of Open Access Journals (Sweden)

    Jing eSun

    2014-02-01

    Full Text Available Influenza viruses continue to cause substantial morbidity and mortality worldwide. Fast gene mutation on surface proteins of influenza virus result in increasing resistance to current vaccines and available antiviral drugs. Broadly neutralizing antibodies represent targets for prophylactic and therapeutic treatments of influenza. We performed a systematic bioinformatics study of cross-reactivity of neutralizing antibodies against influenza virus surface glycoprotein hemagglutinin (HA. This study utilized the available crystal structures of HA complexed with the antibodies for the analysis of tens of thousands of HA sequences. The detailed description of B-cell epitopes, measurement of epitope area similarity among different strains, and estimation of antibody neutralizing coverage provide insights into cross-reactivity status of existing neutralizing antibodies against influenza virus. We have developed a method to assess the likely cross-reactivity potential of broadly neutralizing antibodies for influenza strains, either newly emerged or existing. Our method catalogs influenza strains by a new concept named discontinuous peptide, and then provide assessment of cross-reactivity. Potentially cross-reactive strains are those that share 100% identity with experimentally verified neutralized strains. By cataloging influenza strains and their B-cell epitopes for known broadly neutralizing antibodies, our method provides guidance for selection of representative strains for further experimental design. The knowledge of sequences, their B-cell epitopes, and differences between historical influenza strains, we enhance our preparedness and the ability to respond to the emerging pandemic threats.

  9. Amyloid-β-Anti-Amyloid-β Complex Structure Reveals an Extended Conformation in the Immunodominant B-Cell Epitope

    Energy Technology Data Exchange (ETDEWEB)

    Miles, Luke A; Wun, Kwok S; Crespi, Gabriela A.N.; Fodero-Tavoletti, Michelle T; Galatis, Denise; Bagley, Christopher J; Beyreuther, Konrad; Masters, Colin L; Cappai, Roberto; McKinstry, William J; Barnham, Kevin J; Parker, Michael W [SVIMR-A; (Hanson); (Heidelberg); (Melbourne)

    2012-04-17

    Alzheimer's disease (AD) is the most common form of dementia. Amyloid-β (Aβ) peptide, generated by proteolytic cleavage of the amyloid precursor protein, is central to AD pathogenesis. Most pharmaceutical activity in AD research has focused on Aβ, its generation and clearance from the brain. In particular, there is much interest in immunotherapy approaches with a number of anti-Aβ antibodies in clinical trials. We have developed a monoclonal antibody, called WO2, which recognises the Aβ peptide. To this end, we have determined the three-dimensional structure, to near atomic resolution, of both the antibody and the complex with its antigen, the Aβ peptide. The structures reveal the molecular basis for WO2 recognition and binding of Aβ. The Aβ peptide adopts an extended, coil-like conformation across its major immunodominant B-cell epitope between residues 2 and 8. We have also studied the antibody-bound Aβ peptide in the presence of metals known to affect its aggregation state and show that WO2 inhibits these interactions. Thus, antibodies that target the N-terminal region of Aβ, such as WO2, hold promise for therapeutic development.

  10. Large-scale analysis of B-cell epitopes on influenza virus hemagglutinin - implications for cross-reactivity of neutralizing antibodies

    DEFF Research Database (Denmark)

    Sun, Jing; Kudahl, Ulrich J.; Simon, Christian;

    2014-01-01

    Influenza viruses continue to cause substantial morbidity and mortality worldwide. Fast gene mutation on surface proteins of influenza virus result in increasing resistance to current vaccines and available antiviral drugs. Broadly neutralizing antibodies (bnAbs) represent targets for prophylactic...... and therapeutic treatments of influenza. We performed a systematic bioinformatics study of cross-reactivity of neutralizing antibodies (nAbs) against influenza virus surface glycoprotein hemagglutinin (HA). This study utilized the available crystal structures of HA complexed with the antibodies for the analysis...... that share 100% identity with experimentally verified neutralized strains. By cataloging influenza strains and their B-cell epitopes for known bnAbs, our method provides guidance for selection of representative strains for further experimental design. The knowledge of sequences, their B-cell epitopes...

  11. Molecular evolution of a central region containing B cell epitopes in the gene encoding the p67 sporozoite antigen within a field population of Theileria parva

    OpenAIRE

    Obara, Isaiah; Ulrike, Seitzer; Musoke, Tony; Paul R Spooner; Jabbar, Ahmed; Odongo, David; Kemp, Stephen; Silva, Joana C.; Bishop, Richard P.

    2015-01-01

    Protective immunity induced by the infective sporozoite stage of Theileria parva indicates a potential role for antibodies directed against conserved serologically reactive regions of the major sporozoite surface antigen p67 in vaccination to control the parasite. We have examined the allelic variation and determined the extent of B cell epitope polymorphism of the gene encoding p67 among field isolates originating from cattle exposed to infected ticks in the Marula area of the rift valley in...

  12. Prediction of B Cell Epitope of DMRT Protein in Oreochromis niloticus%尼罗罗非鱼DMRT蛋白 B细胞表位的预测

    Institute of Scientific and Technical Information of China (English)

    杨东; 刘红艳; 张繁荣; 余来宁

    2008-01-01

    [Objective] The research aimed to predict the B cell epitope of DMRT protein in Oreochromis niloticus. [Method] The secondary structure of amino acid sequence of DMRT protein was revealed by Garnier-Robson, Chou-Fasman and Karplus-Schulz methods. The hydrophilicity plot, surface probability and antigenic index were obtained by Kyte-Doolittle, Emini and Jameson-Wolf methods, respectively. Based on the above results, the B cell epitopes for DMRT were predicted. [Result] Both the prediction results from Garnier-Robson, Chou-Fasman methods indicated that the α-helix centers of DMRT protein in O. niloticus were in the N terminal No. 31-56, 68-75, 110-116, 209-211 and 239-243; the β-sheet centers of DMRT protein in O. niloticus were in the N terminal No. 95-99, 177-183, 225-234 and 251-254. With the assistant of Kyte-Doolittle, Emini and Jameson-Wolf methods, the B cell epitopes for DMRT were located in or nearby the N terminal No. 13-16, 35-38, 47-54,84-93, 101-109, 127-156, 166-177 and 198-201. [Conclusion] These results are helpful for preparing the antibody of DMRT protein and revealing the sex determination mechanism of O. niloticus.

  13. Identification of Immunodominant B-cell Epitope Regions of Reticulocyte Binding Proteins in Plasmodium vivax by Protein Microarray Based Immunoscreening.

    Science.gov (United States)

    Han, Jin-Hee; Li, Jian; Wang, Bo; Lee, Seong-Kyun; Nyunt, Myat Htut; Na, Sunghun; Park, Jeong-Hyun; Han, Eun-Taek

    2015-08-01

    Plasmodium falciparum can invade all stages of red blood cells, while Plasmodium vivax can invade only reticulocytes. Although many P. vivax proteins have been discovered, their functions are largely unknown. Among them, P. vivax reticulocyte binding proteins (PvRBP1 and PvRBP2) recognize and bind to reticulocytes. Both proteins possess a C-terminal hydrophobic transmembrane domain, which drives adhesion to reticulocytes. PvRBP1 and PvRBP2 are large (> 326 kDa), which hinders identification of the functional domains. In this study, the complete genome information of the P. vivax RBP family was thoroughly analyzed using a prediction server with bioinformatics data to predict B-cell epitope domains. Eleven pvrbp family genes that included 2 pseudogenes and 9 full or partial length genes were selected and used to express recombinant proteins in a wheat germ cell-free system. The expressed proteins were used to evaluate the humoral immune response with vivax malaria patients and healthy individual serum samples by protein microarray. The recombinant fragments of 9 PvRBP proteins were successfully expressed; the soluble proteins ranged in molecular weight from 16 to 34 kDa. Evaluation of the humoral immune response to each recombinant PvRBP protein indicated a high antigenicity, with 38-88% sensitivity and 100% specificity. Of them, N-terminal parts of PvRBP2c (PVX_090325-1) and PvRBP2 like partial A (PVX_090330-1) elicited high antigenicity. In addition, the PvRBP2-like homologue B (PVX_116930) fragment was newly identified as high antigenicity and may be exploited as a potential antigenic candidate among the PvRBP family. The functional activity of the PvRBP family on merozoite invasion remains unknown.

  14. Linear B-cell epitope mapping of MAPK3 and MAPK4 from Leishmania braziliensis: implications for the serodiagnosis of human and canine leishmaniasis.

    Science.gov (United States)

    Menezes-Souza, Daniel; de Oliveira Mendes, Tiago Antônio; de Araújo Leão, Ana Carolina; de Souza Gomes, Matheus; Fujiwara, Ricardo Toshio; Bartholomeu, Daniella Castanheira

    2015-02-01

    The correct and early identification of humans and dogs infected with Leishmania are key steps in the control of leishmaniasis. Additionally, a method with high sensitivity and specificity at low cost that allows the screening of a large number of samples would be extremely valuable. In this study, we analyzed the potential of mitogen-activated protein kinase 3 (MAPK3) and mitogen-activated protein kinase 4 (MAPK4) proteins from Leishmania braziliensis to serve as antigen candidates for the serodiagnosis of human visceral and tegumentary leishmaniasis, as well as canine visceral disease. Moreover, we mapped linear B-cell epitopes in these proteins and selected those epitopes with sequences that were divergent in the corresponding orthologs in Homo sapiens, in Canis familiaris, and in Trypanosoma cruzi. We compared the performance of these peptides with the recombinant protein using ELISA. Both MAPK3 and MAPK4 recombinant proteins showed better specificity in the immunodiagnosis of human and canine leishmaniasis than soluble parasite antigens and the EIE-leishmaniose-visceral-canina-bio-manguinhos (EIE-LVC) kit. Furthermore, the performance of this serodiagnosis assay was improved using synthetic peptides corresponding to B-cell epitopes derived from both proteins.

  15. Antibodies to both terminal and internal B-cell epitopes of Francisella tularensis O-polysaccharide produced by patients with tularemia.

    Science.gov (United States)

    Lu, Zhaohua; Perkins, Hillary M; Sharon, Jacqueline

    2014-02-01

    Francisella tularensis, the Gram-negative bacterium that causes tularemia, is considered a potential bioterrorism threat due to its low infectivity dose and the high morbidity and mortality from respiratory disease. We previously characterized two mouse monoclonal antibodies (MAbs) specific for the O-polysaccharide (O antigen [OAg]) of F. tularensis lipopolysaccharide (LPS): Ab63, which targets a terminal epitope at the nonreducing end of OAg, and Ab52, which targets a repeating internal OAg epitope. These two MAbs were protective in a mouse model of respiratory tularemia. To determine whether these epitope types are also targeted by humans, we tested the ability of each of 18 blood serum samples from 11 tularemia patients to inhibit the binding of Ab63 or Ab52 to F. tularensis LPS in a competition enzyme-linked immunosorbent assay (ELISA). Although all serum samples had Ab63- and Ab52-inhibitory activities, the ratios of Ab63 to Ab52 inhibitory potencies varied 75-fold. However, the variation was only 2.3-fold for sequential serum samples from the same patient, indicating different distributions of terminal- versus internal-binding antibodies in different individuals. Western blot analysis using class-specific anti-human Ig secondary antibodies showed that both terminal- and internal-binding OAg antibodies were of the IgG, IgM, and IgA isotypes. These results support the use of a mouse model to discover protective B-cell epitopes for tularemia vaccines or prophylactic/therapeutic antibodies, and they present a general strategy for interrogating the antibody responses of patients and vaccinees to microbial carbohydrate epitopes that have been characterized in experimental animals.

  16. Identification of a novel canine distemper virus B-cell epitope using a monoclonal antibody against nucleocapsid protein.

    Science.gov (United States)

    Yi, Li; Cheng, Yuening; Zhang, Miao; Cao, Zhigang; Tong, Mingwei; Wang, Jianke; Zhao, Hang; Lin, Peng; Cheng, Shipeng

    2016-02-01

    Canine distemper virus (CDV) is a member of the genus Morbillivirus within the family Paramyxoviridae and has caused severe economic losses in China. Nucleocapsid protein (N) is the major structural viral protein and can be used to diagnose CDV and other morbilliviruses. In this study, a specific monoclonal antibody, 1N8, was produced against the CDV N protein (amino acids 277-471). A linear N protein epitope was identified by subjecting a series of partially overlapping synthesized peptides to enzyme-linked immunosorbent assay (ELISA) analysis. The results indicated that (350)LNFGRSYFDPA(360) was the minimal linear epitope that could be recognized by mAb 1N8. ELISA assays revealed that mouse anti-CDV sera could also recognize the minimal linear epitope. Alignment analysis of the amino acid sequences indicated that the epitope was highly conserved among CDV strains. Furthermore, the epitope was conserved among other morbilliviruses, which was confirmed with PRRV using western blotting. Taken together, the results of this study may have potential applications in the development of suitable diagnostic techniques for CDV or other morbilliviruses. PMID:26514066

  17. Mapping B-cell epitopes for the peroxidoxin of Leishmania (Viannia braziliensis and its potential for the clinical diagnosis of tegumentary and visceral leishmaniasis.

    Directory of Open Access Journals (Sweden)

    Daniel Menezes-Souza

    Full Text Available The search toward the establishment of novel serological tests for the diagnosis of leishmaniasis and proper differential diagnosis may represent one alternative to the invasive parasitological methods currently used to identify infected individuals. In the present work, we investigated the potential use of recombinant peroxidoxin (rPeroxidoxin of Leishmania (Viannia braziliensis as a potential antigen for the immunodiagnosis of human tegumentary (TL and visceral leishmaniasis (VL and canine visceral leishmaniasis (CVL. Linear B-cell epitope mapping was performed to identify polymorphic epitopes when comparing orthologous sequences present in Trypanosoma cruzi, the agent for Chagas disease (CD, and the Homo sapiens and Canis familiaris hosts. The serological assay (ELISA demonstrated that TL, VL and CVL individuals showed high levels of antibodies against rPeroxidoxin, allowing identification of infected ones with considerable sensitivity and great ability to discriminate (specificity between non-infected and CD individuals (98.46% and 100%; 98.18% and 95.71%; 95.79% and 100%, respectively. An rPeroxidoxin ELISA also showed a greater ability to discriminate between vaccinated and infected animals, which is an important requirement for the public campaign control of CVL. A depletion ELISA assay using soluble peptides of this B-cell epitope confirmed the recognition of these sites only by Leishmania-infected individuals. Moreover, this work identifies two antigenic polymorphic linear B-cell epitopes of L. braziliensis. Specific recognition of TL and VL patients was confirmed by significantly decreased IgG reactivity against rPeroxidoxin after depletion of peptide-1- and peptide-2-specific antibodies (peptide 1: reduced by 32%, 42% and 5% for CL, ML and VL, respectively; peptide-2: reduced by 24%, 22% and 13% for CL, ML and VL, respectively and only peptide-2 for CVL (reduced 9%. Overall, rPeroxidoxin may be a potential antigen for the

  18. T cell-independent type I antibody response against B cell epitopes expressed repetitively on recombinant virus particles

    OpenAIRE

    Fehr, Thomas; Skrastina, Dace; Pumpens, Paul; Zinkernagel, Rolf M.

    1998-01-01

    Recombinant viral or virus-like particles offer new tools for vaccine development. This study investigated hepatitis B core antigen (HBcAg) capsids and RNA phage Qβ coats as carriers of a foreign epitope to induce antibody responses in mice. HBcAg capsids were shown to induce T cell-independent (TI) antibodies. We found that these particles behave as antigen-specific TI type 1 (TI-1) Ag comparable to other rigidly structured viruses. When a 5-aa long epitope of the pre-S1 domain of hepatitis ...

  19. Antigen presentation by non-immune B-cell hybridoma clones: presentation of synthetic antigenic sites reveals clones that exhibit no specificity and clones that present only one epitope

    Science.gov (United States)

    Cohly, H. H.; Morrison, D. R.; Atassi, M. Z.

    1989-01-01

    Recently, we reported the preparation and antigen-presenting properties of hybridoma B-cell clones obtained after fusing non-secreting, non-antigen presenting Balb/c 653-myeloma cells with non-immune SJL spleen cells. It was found that antigen presentation at the clonal level can be specific or non-specific, depending on the particular B-cell clone. In the present work, one specific and one general presenter B-cell clones were tested for their epitope presentation ability to SJL T-cells that were specific to lysozyme or myoglobin. B-cell clone A1G12, a general presenter which presented both lysozyme and myoglobin to their respective T-cell lines, was found to present all five myoglobin epitopes while clone A1L16, a lysozyme specific presenter presented only one of the three epitopes of lysozyme. The latter reveals a hitherto unknown submolecular specificity (to a given epitope within a protein) for antigen presenting cells at the clonal level. Therefore, the specificity of T-cell recognition does not only derive from the T-cell but may also be dependent on the epitope specificity of the antigen-presenting B-cell.

  20. Induction of neutralizing antibodies by a tobacco chloroplast-derived vaccine based on a B cell epitope from canine parvovirus

    International Nuclear Information System (INIS)

    The 2L21 epitope of the VP2 protein from the canine parvovirus (CPV), fused to the cholera toxin B subunit (CTB-2L21), was expressed in transgenic tobacco chloroplasts. Mice and rabbits that received protein-enriched leaf extracts by parenteral route produced high titers of anti-2L21 antibodies able to recognize the VP2 protein. Rabbit sera were able to neutralize CPV in an in vitro infection assay with an efficacy similar to the anti-2L21 neutralizing monoclonal antibody 3C9. Anti-2L21 IgG and seric IgA antibodies were elicited when mice were gavaged with a suspension of pulverized tissues from CTB-2L21 transformed plants. Combined immunization (a single parenteral injection followed by oral boosters) shows that oral boosters help to maintain the anti-2L21 IgG response induced after a single injection, whereas parenteral administration of the antigen primes the subsequent oral boosters by promoting the induction of anti-2L21 seric IgA antibodies. Despite the induced humoral response, antibodies elicited by oral delivery did not show neutralizing capacity in the in vitro assay. The high yield of the fusion protein permits the preparation of a high number of vaccine doses from a single plant and makes feasible the oral vaccination using a small amount of crude plant material. However, a big effort has still to be done to enhance the protective efficacy of subunit vaccines by the oral route

  1. 应用生物信息学分析大米过敏原RAG1的B细胞表位(英文)%Bioinformatics Analysis on B cell Epitopes of Rice Allergen RAG1

    Institute of Scientific and Technical Information of China (English)

    李燕芳; 何颖; 邹泽红

    2012-01-01

    [Objective] To predict the secondary structure and B cell epitopes of the rice major allergen RAG1. [Method] The amino acid sequence of rice allergen RAG1 was acquired from Expasy protein database. The secondary structure of RAG1 was predicted by DNAStar Protean software with Gamier-Robson program, Chou-Fasman program and Karplus-Schulz program; the B cell epitopes of RAG1 was predicted with the Kyte Doolittle hydrophilic program, Emini surface accessibility program and Jameson-Wolf antigenic index program. [Result] The predictions on secondary structure and B cell epitopes showed that the regions of 33-44, 119-129, 155-163 were the dominant B cell epitopes. [Conclusion] This study predicted the potential dominant B cell epitopes in rice allergen RAG1 by comprehensive use of multi-methods and multi-parameters, and provided a theoretical basis for further researches on identification, antigen modification and epitope vaccine design of RAG1 B cell epitopes.%[目的]预测大米主要过敏原RAG1的二级结构及B细胞表位。[方法]从Expasy蛋白质数据库中获得编码大米过敏原RAG1的氨基酸序列并以此氨基酸序列为基础,通过DNAStarProtean软件,采用Gamier-Robson方案、Chou-Fasman方案和Karplus-Schulz方案预测RAG1的二级结构,用Kyte-Doolittle亲水性方案、Emini表面可及性方案、Jameson-Wolf抗原性指数方案综合预测RAG1的B细胞表位。[结果]对大米过敏原RAG1的二级结构和B细胞表位预测的结果表明,第33~44、119~129、155~163区段可能是B细胞的优势表位。[结论]本研究综合应用多方法多参数预测大米过敏原RAG1潜在的B细胞优势表位,为RAG1B细胞表位的进一步鉴定及其抗原性改造、表位疫苗设计等研究提供了理论依据。

  2. Serum Concentrations of Antibodies against Outer Membrane Protein P6, Protein D, and T- and B-Cell Combined Antigenic Epitopes of Nontypeable Haemophilus influenzae in Children and Adults of Different Ages.

    Science.gov (United States)

    Hua, Chun-Zhen; Hu, Wei-Lin; Shang, Shi-Qiang; Li, Jian-Ping; Hong, Li-Quan; Yan, Jie

    2016-02-01

    Nontypeable Haemophilus influenzae (NTHi) is one of the most common etiologies of acute otitis media, rhinosinusitis, and pneumonia. Outer membrane proteins (OMPs) are the main focus in new vaccine development against NTHi, as the H. influenzae type b (Hib) vaccine does not cover noncapsulated NTHi. The OMPs P6 and protein D are the most promising candidate antigens for an NTHi vaccine, and low antibody levels against them in serum may be correlated with infection caused by NTHi. In the current study, we measured the antibody titers against P6, protein D, and their T- and B-cell combined peptide epitopes in healthy individuals of different ages. We found that children B-cell combined antigenic epitopes. Antibody titers increased at ages 1 to 6 months, peaked at 7 months to 3 years, and remained high at 4 to 6 years. The antibody titers started to decrease after 6 years and were the lowest in the 21- to 30-year group. The geometric mean titers (GMTs) of T- and B-cell combined antigenic epitopes in P6 and protein D were positively correlated with those of the protein antigens. Among 12 peptides tested, P6-61, P6-123, and protein D-167 epitopes were better recognized than others in human serum. These findings might contribute to the development of an effective serotype-independent vaccine for H. influenzae. PMID:26677200

  3. Bioinformatics Analysis on B Cell Epitopes of Rice Allergen RAG1%应用生物信息学分析大米过敏原RAG1的B细胞表位

    Institute of Scientific and Technical Information of China (English)

    李燕芳; 何颖; 邹泽红

    2012-01-01

    [目的]预测大米主要过敏原RAG1的二级结构及B细胞表位.[方法]从Expasy蛋白质数据库中获得编码大米过敏原RAG1的氨基酸序列并以此氨基酸序列为基础,通过DNAStar Protean软件,采用Gamier-Robson方案、Chou-Fasman方案和Karplus-Schulz方案预测RAG1的二级结构,用Kyte-Doolittle亲水性方案、Emini表面可及性方案、Jameson-Wolf抗原性指数方案综合预测RAG1的B细胞表位.[结果]对大米过敏原RAG1的二级结构和B细胞表住预测的结果表明,第33 ~44、119 ~129、155~163区段可能是B细胞的优势表位.[结论]该研究综合应用多方法多参数预测大米过敏原RAG1潜在的B细胞优势表位,为RAG1 B细胞表位的进一步鉴定及其抗原性改造、表位疫苗设计等研究提供了理论依据.%[Objective] To predict secondary structure and B cell epilopes of the rice major allergen RAG1. [ Method ] The amino acid sequence of rice allergen RAG1 was acquired from Expasy protein database. The secondary structure of RAG1 was predicted by DNAStar Protean software with Gamier-Robson program, Chou-Fasman program and Karplus-Schulz program; the B cell epitopes of RAG1 was predicted with the Kyte-Doolittle hydrophilic program, Emini surface accessibility program and Jameson-Wolf antigenic index program. [ Result] The predictions on secondary structure and B cell epitopes showed that the regions of 33 -44, 119 - 129, 155 - 163 were the dominant B cell epitopes. [Conclusion] This study predicted the potential dominant B cell epitopes in rice allergen RAG1 by comprehensive use of multi-methods and multi-parameters, and provided a theoretical basis for further researches on identification, antigen modification and epitope vaccine design of RAG1 B cell epitopes.

  4. Prediction of Secondary Structure and B Cell Epitope of GH Protein from Acipenser sinensis%中华鲟GH蛋白二级结构和B细胞抗原表位的预测

    Institute of Scientific and Technical Information of China (English)

    刘红艳; 杨东; 张繁荣; 余来宁

    2009-01-01

    [Objective] The aim was to predict the secondary structure and B cell epitope of growth hormone (GH) protein from Acipenser sinensis. [Method] With the amino acid sequence of GH protein from A.sinensis as the base, the secondary structure of GH protein from A.sinensis was predicted by the method of Garnier-Robson, Chou-Fasman and Karplus-Schulz, and its cell epitope was predicted by the method of Kyte-Doolittle, Emini and Jameson-Wolf. [Result] The sections of 18-23, 55-56, 67-73, 83-86, 112-114, 151-157 and 209-211 in the N terminal of GH protein molecule had softer structure and these sections could sway or fold to produce more complex tertiary structure. The sections of 19-23, 51-71, 84-95, 128-139, 164-176 and 189-196 in the N terminal of GH protein could be the epitope of B cell and there were flexible regions in these sections or near these sections of GH protein molecule. So the dominant regions could be in these sections or near these sections. [Conclusion] The research provided the basis for the preparation of monoclonal antibody of GH protein from A.sinensis and provided the reference for the discussion for the molecular regulation mechanism of A.sinensis.

  5. Identification and characterization of a virus-specific continuous B-cell epitope on the PrM/M protein of Japanese Encephalitis Virus: potential application in the detection of antibodies to distinguish Japanese Encephalitis Virus infection from West Nile Virus and Dengue Virus infections

    Directory of Open Access Journals (Sweden)

    Liu Wen-Xin

    2010-09-01

    Full Text Available Abstract Background Differential diagnose of Japanese encephalitis virus (JEV infection from other flavivirus especially West Nile virus (WNV and Dengue virus (DV infection was greatly hindered for the serological cross-reactive. Virus specific epitopes could benefit for developing JEV specific antibodies detection methods. To identify the JEV specific epitopes, we fully mapped and characterized the continuous B-cell epitope of the PrM/M protein of JEV. Results To map the epitopes on the PrM/M protein, we designed a set of 20 partially overlapping fragments spanning the whole PrM, fused them with GST, and expressed them in an expression vector. Linear epitope M14 (105VNKKEAWLDSTKATRY120 was detected by enzyme-linked immunosorbent assay (ELISA. By removing amino acid residues individually from the carboxy and amino terminal of peptide M14, we confirmed that the minimal unit of the linear epitope of PrM/M was M14-13 (108KEAWLDSTKAT118. This epitope was highly conserved across different JEV strains. Moreover, this epitope did not cross-react with WNV-positive and DENV-positive sera. Conclusion Epitope M14-13 was a JEV specific lineal B-cell epitpe. The results may provide a useful basis for the development of epitope-based virus specific diagnostic clinical techniques.

  6. Antibody-protein interactions: benchmark datasets and prediction tools evaluation

    Directory of Open Access Journals (Sweden)

    Ponomarenko Julia V

    2007-10-01

    Full Text Available Abstract Background The ability to predict antibody binding sites (aka antigenic determinants or B-cell epitopes for a given protein is a precursor to new vaccine design and diagnostics. Among the various methods of B-cell epitope identification X-ray crystallography is one of the most reliable methods. Using these experimental data computational methods exist for B-cell epitope prediction. As the number of structures of antibody-protein complexes grows, further interest in prediction methods using 3D structure is anticipated. This work aims to establish a benchmark for 3D structure-based epitope prediction methods. Results Two B-cell epitope benchmark datasets inferred from the 3D structures of antibody-protein complexes were defined. The first is a dataset of 62 representative 3D structures of protein antigens with inferred structural epitopes. The second is a dataset of 82 structures of antibody-protein complexes containing different structural epitopes. Using these datasets, eight web-servers developed for antibody and protein binding sites prediction have been evaluated. In no method did performance exceed a 40% precision and 46% recall. The values of the area under the receiver operating characteristic curve for the evaluated methods were about 0.6 for ConSurf, DiscoTope, and PPI-PRED methods and above 0.65 but not exceeding 0.70 for protein-protein docking methods when the best of the top ten models for the bound docking were considered; the remaining methods performed close to random. The benchmark datasets are included as a supplement to this paper. Conclusion It may be possible to improve epitope prediction methods through training on datasets which include only immune epitopes and through utilizing more features characterizing epitopes, for example, the evolutionary conservation score. Notwithstanding, overall poor performance may reflect the generality of antigenicity and hence the inability to decipher B-cell epitopes as an

  7. Identification of immunodominant regions and linear B cell epitopes of the gE envelope protein of varicella-zoster virus.

    Science.gov (United States)

    Fowler, W J; Garcia-Valcarcel, M; Hill-Perkins, M S; Murphy, G; Harper, D R; Jeffries, D J; Burns, N R; Adams, S E; Kingsman, A J; Layton, G T

    1995-12-20

    The envelope proteins of varicella-zoster virus (VZV) are highly immunogenic and one of the most abundant is glycoprotein E (gE). However, its immunodominant regions and epitopes have not been identified. In this study, using human sera from individuals with recent varicella or zoster infections, we have localized antigenic sequences of gE using recombinant hybrid Ty-virus-like particles (VLPs) carrying overlapping fragments of the gE protein. gE(1-134)-VLPs (particles carrying amino acids 1-134 of gE) and, to a lesser extent, gE(101-161)-VLPs were found to be the most antigenic when tested by Western blotting and ELISA. Other fragments of gE (spanning residues 161-623) showed weak or no antigenicity. Pepscan analysis of human sera on overlapping synthetic peptides representing residues 1-135 of gE revealed that the most antigenic region was between residues 50 and 135. Three immunodominant sequences (residues 86-105, 116-135, and, to a lesser extent, 56-75) were detected using sera from both varicella and zoster patients. All sera from varicella, but not zoster, patients reacted strongly with an epitope in peptide 66-85. Other epitopes were recognized weakly by some varicella or zoster sera. More sera need to be tested to assess the potential disease specificity of these epitopes. The neutralizing monoclonal antibody (MAb) IF-B9 reacted with residues 71-90; however, another neutralizing MAb, SG1A, which bound to both gE(1-134)-VLPs and gE(101-161)-VLPs did not bind to any peptide. The identification of immunodominant sequences of gE will help toward the development of a subunit VZV vaccine. PMID:8553555

  8. Generation and characterization of a recombinant chimeric protein (rCpLi) consisting of B-cell epitopes of a dermonecrotic protein from Loxosceles intermedia spider venom.

    Science.gov (United States)

    Mendes, T M; Oliveira, D; Figueiredo, L F M; Machado-de-Avila, R A; Duarte, C G; Dias-Lopes, C; Guimarães, G; Felicori, L; Minozzo, J C; Chávez-Olortegui, C

    2013-06-01

    A chimeric protein was constructed expressing three epitopes of LiD1, a dermonecrotic toxin from the venom of Loxosceles intermedia spider. This species is responsible for a large number of accidents involving spiders in Brazil. We demonstrated that the chimeric protein (rCpLi) generated is atoxic and that antibodies previously developed in rabbits against synthetic epitopes reactive with rCpLi in ELISA and immunoblot assays. The antibody response in rabbits against the rCpLi was evaluated by ELISA and we have detected an antibody response in all immunized animals. Overlapping peptides covering the amino acid sequence of the rCpLi were synthesized on a cellulose membrane, and their recognition by rabbit anti-rCpLi serum assessed. Three different antigenic regions were identified. The percentage of inhibition of the dermonecrotic, hemorrhagic and edematogenic activities caused by the recombinant protein LiD1r in naïve rabbits was assessed by pre-incubation with anti-rCpLi antibodies. Anti-rCpLi induced good dermonecrotic and hemorrhagic protection. The levels of protection were similar to the antiboides anti-LiD1r. In summary, we have developed a polyepitope recombinant chimeric protein capable of inducing multiple responses of neutralizing antibodies in a rabbit model. This engineered protein may be a promising candidate for therapeutic serum development or vaccination.

  9. Conjugation of alginate to a synthetic peptide containing T- and B-cell epitopes as an induction for protective immunity against Pseudomonas aeruginosa.

    Science.gov (United States)

    Farjaha, Ali; Owlia, Parviz; Siadat, Seyed Davar; Mousavi, Seyed Fazlollah; Shafieeardestani, Mehdi

    2014-12-20

    Pseudomonas aeruginosa is a major cause of respiratory tract infections worldwide, particularly in hospitalized patients with immunosuppressed conditions and cystic fibrosis (CF). Excessive use of antibiotics means that there is currently resistance among bacterial infections to many drugs. Vaccination is a strategy that can reduce mortality and morbidity rates in infections such as those caused by P. aeruginosa. Alginate has a critical role in such infections and affects pathogenicity of the bacterium. In this work, the bioinformatics approach was used to design and synthesis a carrier peptide (ERRANAVRDVLVNEY), derived from OMP F P. aeruginosa. This peptide contained both B- and T-cell epitopes based on prediction models. Conjugation of alginate to carrier peptide was performed and then analyzed by Fourier transform infrared spectroscopy (FTIR). Results of this study on mice showed that the conjugate elicited anti-alginate-IgG that were not detected after immunization with naive alginate. The effect of the antibodies to alginate conjugate was evaluated as highly opsonic and showed moderate to high-level killing activity against two mucoid strains. IgG1 was also dominant among IgG subclasses. Mice vaccinated with the conjugate vaccine survived lethal challenges (2 ×LD 50). Furthermore, using an acute pneumonia model of infection in mice, determined that levels of P. aeruginosa in mice were significantly reduced in the vaccinated group. Thus, tests confirmed ability of this conjugate to elicit protective and opsonophagocytic antibodies that candidate our vaccine for further studies. PMID:25449544

  10. Immune Epitope Database and Analysis Resource (IEDB)

    Data.gov (United States)

    U.S. Department of Health & Human Services — This repository contains antibody/B cell and T cell epitope information and epitope prediction and analysis tools for use by the research community worldwide....

  11. 猪丹毒杆菌SpaA基因的克隆与生物信息学分析%Cloning, sequecing, secondary structure and B-cell epitopes prediction of swine Erysipelothrix rhusiopathiae SpaA

    Institute of Scientific and Technical Information of China (English)

    林琳; 江斌; 吴胜会; 张世忠

    2013-01-01

    The aims of this study was to clone and sequence the SpaA gene of Erysipelothrix rhusiopathiae and predict its secondary structure and B-cell epitopes,which provides a theoretical basis for the study of immune mechanism and subunit vaccine.The SpaA gene was amplified,cloned,sequenced and phylogenetic analyzed.By using bioinformatics methods,the secondary structure and B-cell preponderant epitope of SpaA were predicted.The results showed that the spaA gene is 1 881 bp,encoding 626 amino acids.The phylogenetic analysis of the SpaA gene indicated the distance between 2 separated strain of Erysipelothrix rhusiopathiae and those of GenBank was far,and 2 separated strain became a new branch.Using the SOPMA method,prediction of the secondary structure of the SpaA showed thatα-helix,random coils and extended strand were the main structural type of the flexible region in secondary structure,and contain a small amount of β-turn.It was supposed the SpaA protein contain 14 potential antigen epitopes and 8 potential Nmyristoylation sites.These results provided a theoretical basis for the further study of immune mechanisms and epitope vaccine design for the pathogen.%旨在克隆猪丹毒杆菌表面保护性抗原A(surface protein A,SpaA)的编码基因,并预测该蛋白的二级结构和B细胞抗原表位,从而探讨猪丹毒杆菌SpaA蛋白在免疫保护中所起的作用.首先对猪丹毒杆菌SpaA基因进行PCR扩增、克隆和测序,并进行同源性比较.应用生物信息学方法,对猪丹毒杆菌SpaA蛋白的二级结构和B细胞抗原表位进行预测.结果显示,猪丹毒杆菌SpaA基因全长1 881 bp,编码626个氨基酸,发育进化树结果表明分离的2株猪丹毒杆菌菌株与GenBank中其他菌株在进化树中关系较远,自成一个分支.二级结构的预测结果显示该蛋白主要以无规则卷曲、α螺旋和延伸链为主,只有少数的β转角;推测该蛋白有14个B细胞优势抗原表位区域、8个N-肉豆蔻酰化

  12. B-cell epitopes in NTS-DBL1α of PfEMP1 recognized by human antibodies in Rosetting Plasmodium falciparum.

    Science.gov (United States)

    Albrecht, Letusa; Angeletti, Davide; Moll, Kirsten; Blomqvist, Karin; Valentini, Davide; D'Alexandri, Fabio Luiz; Maurer, Markus; Wahlgren, Mats

    2014-01-01

    Plasmodium falciparum is the most lethal of the human malaria parasites. The virulence is associated with the capacity of the infected red blood cell (iRBC) to sequester inside the deep microvasculature where it may cause obstruction of the blood-flow when binding is excessive. Rosetting, the adherence of the iRBC to uninfected erythrocytes, has been found associated with severe malaria and found to be mediated by the NTS-DBL1α-domain of Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1). Here we show that the reactivity of plasma of Cameroonian children with the surface of the FCR3S1.2-iRBC correlated with the capacity to disrupt rosettes and with the antibody reactivity with a recombinant PfEMP1 (NTS-DBL1α of IT4var60) expressed by parasite FCR3S1.2. The plasma-reactivity in a microarray, consisting of 96 overlapping 15-mer long peptides covering the NTS-DBL1α domain from IT4var60 sequence, was compared with their capacity to disrupt rosettes and we identified five peptides where the reactivity were correlated. Three of the peptides were localized in subdomain-1 and 2. The other two peptide-sequences were localized in the NTS-domain and in subdomain-3. Further, principal component analysis and orthogonal partial least square analysis generated a model that supported these findings. In conclusion, human antibody reactivity with short linear-peptides of NTS-DBL1α of PfEMP1 suggests subdomains 1 and 2 to hold anti-rosetting epitopes recognized by anti-rosetting antibodies. The data suggest rosetting to be mediated by the variable areas of PfEMP1 but also to involve structurally relatively conserved areas of the molecule that may induce biologically active antibodies.

  13. Benchmarking Benchmarks

    NARCIS (Netherlands)

    D.C. Blitz (David)

    2011-01-01

    textabstractBenchmarking benchmarks is a bundle of six studies that are inspired by the prevalence of benchmarking in academic finance research as well as in investment practice. Three studies examine if current benchmark asset pricing models adequately describe the cross-section of stock returns. W

  14. Optimization screening for the B cell epitope of the extracellular domain of the follicle stimulating hormone receptor%卵泡刺激素受体(FSHR)胞外区B细胞表位的优化筛选

    Institute of Scientific and Technical Information of China (English)

    杨利华; 李鸥; 王树峰; 梁志清; 吴玉章; 何畏

    2012-01-01

    目的:采用生物信息学技术,对前期研究获得的卵泡刺激素受体(FSHR)的B细胞表位肽段进一步筛选、优化,以获得理想的FSHR靶标抗原.方法:①利用InsightⅡ分子模拟软件寻找FSHR与FSH相互作用的区域.②应用DNA STAR 软件中的Protein模块对优化后抗原进行综合分析.③肽结合实验对优化后抗原进行免疫原性检测.结果:≥5个氨基酸片段的柔性区域位于FSHR第30 - 44、52 - 65、112 - 121、174 - 182、190 - 210、223 - 245区段.当FSHR胞外区第37位缬氨酸被赖氨酸或谷氨酸替代时,具有较好的亲水性及抗原性.而肽结合实验证实肽32 - 44具有更好的免疫原性.结论:FSHR胞外区肽段32-44有可能成为避孕疫苗的理想抗原.%Objective; To obtain the desired antigen targeting - FSHR, we screened and optimized the B cell epitope for the extracellular domain of the follicle stimulating hormone receptor (FSHR) . Methods; ①Insight II molecular simulation software was used to i-dentity amino acid sites of interaction interface between FSH and FSHR. ②The secondary structure and surface properties of the extracellular domain of FSHR, such as physical and chemical properties, hydrophilicity, antigenicity and plasticity, were analyzed by a variety of methods. ③The peptide of the epitopes was synthesized and used for coating streptavidin plate. The immunogenicity of the peptides was determined. Results; Many distinct antigenic epitopes in the extracellular domain of FSHR were identified by computation, the possible location of which was in the regions of 30 ~ 44, 52 ~ 65 , 112 ~ 121, 174 ~ 182, 190 ~ 210 and 223 ~ 245. When the FSHR ectodomain 37th valine was replaced by lysine and glutamic acid, the antigen had better hydrophilicity and antigenic. However, the peptide 32-44 was confirmed the best immunogenicity in ELISA assay. Conclusion; FSHR ectodomain peptide 32 ~44 can be the ideal contraceptive vaccine antigens.

  15. 猪带绦虫六钩蚴TSO45-4B抗原FnⅢ结构域相应的线性B细胞表位肽免疫原性研究%Research on immunity response about Taenia solium oncosphere TSO45-4B antigens FnⅢ structure domain linear B cells epitope peptides

    Institute of Scientific and Technical Information of China (English)

    王媛媛; 陶志勇; 杨小迪; 王小莉; 常雪莲; 陈勇; 孙新; 夏惠; 方强

    2013-01-01

    Objective: To observe the humoral immune response induced by Taenia solium oncosphere TSO45-4B antigens Fn Ⅲ structure domain linear B cells epitope peptides in mice. Methods: The two predicted B cell epitope peptides of TSO45-4B Fn Ⅲ structure domain conjugated with carrier protein of keyhole limpet hemocyanin were synthesized and used to immunize mice. The mice specific serum antibody titer to the epitope peptides synthesized was tested by ELISA. Results: The specific antibody to one of the predicted epitope peptides synthesized was found in mice serum,and the titer was 1: 1 280. Conclusions: One of the two predicted linear B cell epitope peptides of TSO45-4B FnⅢ structure domain can induce the humoral immune response in mice.%目的:观察载体蛋白偶联的TSO45-4B抗原FnⅢ结构域相应的线性B细胞表位肽诱导的体液免疫反应.方法:人工合成TSO45-4B抗原FnⅢ结构域2条预测表位肽,偶联钥孔血蓝蛋白免疫小鼠,采用ELISA法检测小鼠血清中预测表位肽特异性抗体滴度.结果:免疫小鼠血清中检测到1条预测表位肽特异性抗体,其效价达到1:1 280.结论:设计的1条TSO45-4B抗原FnⅢ结构域线性B细胞表位肽可诱导小鼠产生体液免疫反应.

  16. Immune epitope database analysis resource

    DEFF Research Database (Denmark)

    Kim, Yohan; Ponomarenko, Julia; Zhu, Zhanyang;

    2012-01-01

    The immune epitope database analysis resource (IEDB-AR: http://tools.iedb.org) is a collection of tools for prediction and analysis of molecular targets of T- and B-cell immune responses (i.e. epitopes). Since its last publication in the NAR webserver issue in 2008, a new generation of peptide:MH...

  17. Prediction and identification of Taenia solium oncosphere TSO45-4B antigen FnⅢ structure domain linear B cell epitopes%猪带绦虫六钩蚴TSO45-4B抗原FnⅢ结构域线性B细胞表位预测及鉴定

    Institute of Scientific and Technical Information of China (English)

    王媛媛; 王小莉; 常雪莲; 陶志勇; 夏惠; 方强

    2012-01-01

    Objective To predict and identify Taenia solium oncosphere TSO45-4B antigen FnⅢ structure domain linear B cell epitopes. Methods The B cell epitopes of TSO45-4B FnⅢ structure domain were predicted through the sequence analysis by using bioinformatics online tools and the protein space conformation was predicted by SWISS-MODEL. The peptides were synthesized according to the predicted linear epitopes. The immunoreactivity of sera of cysticercosis patients to the peptides synthesized was tested by using ELISA. Results Two linear B cell epitopes of TSO45-4B FnⅢ structure domain were predicted, and one of the predicted epitope peptides synthesized could be recognized by the sera of cysticercosis patients. Conclusion Two linear B cell epitopes of TSO45-4B Fn Ⅲ structure domain are predicted and one of them has been confirmed successfully.%目的 预测并鉴定猪带绦虫六钩蚴TSO45-4B抗原FnⅢ结构域线性B细胞表位.方法 利用生物信息学在线工具分析TSO45-4B抗原FnⅢ结构域序列并预测其线性B细胞表位;采用SWISS-MODEL软件预测TSO45-4B的蛋白空间结构,并合成两条预测表位肽.采用酶联免疫吸附试验(ELISA)检测猪囊尾蚴病人血清与两条预测表位肽的免疫反应性.结果 获得2个TSO45-4B抗原FnⅢ结构域线性B细胞预测表位,其中1条预测表位合成肽可为猪囊尾蚴病患者血清识别.结论 成功预测并鉴定了猪带绦虫六钩蚴TSO45-4B抗原FnⅢ结构域线性B细胞表位.

  18. Prediction of the Spatial Structure and B-cell Epitopes of Mycoplasma suis ORF4 Protein%猪附红细胞体ORF4蛋白的空间结构与B细胞抗原表位预测

    Institute of Scientific and Technical Information of China (English)

    单思; 巴彩凤

    2012-01-01

    To predict the spatial structure and B-cell epitopes of Mycoplasma suis ORF4 protein. The secondary structure, tertiary structure, hydrophilicity, flexible region, antigenic index and surface probability were predicted through the nucleotide sequence of AJ504999-ORF4 were analyzed by bioinformatics software and internet routine. The results showed that the potential B cell antigenic epitopes of Mycoplasma suis ORF4 protein were located at 28-34, 54-61aa, whose the secondary structure were without α-helix but rich in β-pleated sheet. Prediction of the spatial structure and B-cell epitopes of Mycoplasma suis ORF4 protein might laid the basis for studies of the design of epitopes vaccine.%为了预测猪附红细胞体(Mycoplasma suis)ORF4蛋白的空间结构和B细胞抗原表位.选择Genebank序列号AJ504999中ORF4基因,应用生物信息软件和互联网在线程序分析ORF4的氨基酸序列预测二、三级结构、亲水性、柔韧性、抗原指数及表面可及性.结果表明:ORF4蛋白二级结构没有α-螺旋,其中柔性结构以β-转角为主,潜在的优势B细胞抗原表位区段主要分布在28~34、54~61氨基酸区段.本研究预测了ORF4蛋白空间结构和B细胞抗原表位,为猪附红细胞体表位疫苗的设计研发提供了指导意义.

  19. Cloning,expression and purification of B cell epitope antigen peptide of EGFR dimerization%EGFR二聚化B细胞表位抗原肤基因克隆、表达与纯化

    Institute of Scientific and Technical Information of China (English)

    朱磊; 吴梅芝; 赵林; 黄绮玲; 梁梅; 李黄金

    2011-01-01

    目的 利用基因工程手段建立表皮生长因子受体(EGFR)二聚化B细胞表位抗原肽MVF-ER的高效制备方法.方法 采用重叠延伸PCR扩增MVF-ER后克隆于表达载体pET32a,于大肠杆菌BL21(DE3)进行表达,产物采用肠激酶酶切和镍离子鳌合亲和层析法纯化.结果 通过10对引物5步重叠延伸得到273bp的扩增产物,目的基因与硫氧环蛋白(Trx)融合后可高效表达,经酶切和层析后得到纯度为95%的抗原肤.结论 成功建立抗原肽"MVF-ER"的高效制备方法,为进一步研究EGFR过表达恶性肿瘤的治疗性疫苗打下了坚实基础.%We aim to establish a high performance preparation system for B cell epitope antigen peptide of EGFR dimerization for further research on therapeutic vaccine of EGFR over-expression tumors. The MVF-ER gene of 273 bp was amplified by splicing overlap extension PCR (SOE-PCR), then cloned into the vector of pET32a, and expressed in E.coli BL21 (DE3) in the form of fusion with Trx. The expression product was purified by Ni+ affinity chromatography. The antigen peptide was recovered from the fusion protein by enterokinase and purified to a purity of 95% confirmed by SDS-PAGE. The results above showed that the preparation method of MVF-ER antigen peptide was successfully established, which will facilitate further study of the therapeutic cancer vaccine.

  20. Analysis of Genome Sequence of App ApxIIA and Its Prediction of Related B Cell Epitopes%猪胸膜肺炎放线杆菌ApxIIA基因的序列分析及其B细胞表位预测

    Institute of Scientific and Technical Information of China (English)

    李任峰; 田香勤; 何启盖; 王自良; 赵坤; 李学斌; 王三虎

    2009-01-01

    The research was to analyze the identity matrix of ApxIIA genes of App isolates and to predict the B cell epitopes of this ApxIIA protein. The ApxIIA genes of the six different App were selected from GenBank to analyze their identity matrix of nucleotide and amino acid by the bioinformatics analysis software. The B cell epitopes of the AY232288.1 ApxIIA protein were predicted based on the analysis parameters of B cell epitopes and the characteristicof the secondary structure. The results showed the ApxIIA genes of six strains share 65.56 % and 88.42% homology at nucleotide and amino acid level respectively. The B cell epitope of ApxIIA protein of AY232288.1 was probably locate or adjacent to its N-terminal region 745~751和801~807. These results provided references for further research of ApxIIA protein function and design of multiepitope-based vaccine of APP.%为了进一步研究猪胸膜肺炎放线杆菌(Actionobacillus pleuropneumoniae,App)ApxIIA基因的结构和功能,选取GenBank中6株不同App分离株,采用生物信息学方法对其ApxIIA基因及其编码氨基酸序列进行同源性比对,并选择其中AY232288.1菌株(湖北分离株)ApxIIA基因为研究对象,分析该基因所编码蛋白质的理化性质,并对其可能形成的二级结构及B细胞表位进行预测和分析.结果表明,6株不同App分离株ApxIIA基因核苷酸及氨基酸序列同源性分别为65.56﹪和88.42﹪,在AY232288.1菌株ApxIIA蛋白的肽链中,745~751和801~807区段可能是其B细胞表位优势区.本研究首次利用生物信息学方法对ApxIIA基因及其蛋白质结构进行了分析和预测,为ApxIIA基因功能的深入研究及APP多表位疫苗的设计奠定了基础.

  1. ElliPro: a new structure-based tool for the prediction of antibody epitopes

    Directory of Open Access Journals (Sweden)

    Fusseder Nicholas

    2008-12-01

    Full Text Available Abstract Background Reliable prediction of antibody, or B-cell, epitopes remains challenging yet highly desirable for the design of vaccines and immunodiagnostics. A correlation between antigenicity, solvent accessibility, and flexibility in proteins was demonstrated. Subsequently, Thornton and colleagues proposed a method for identifying continuous epitopes in the protein regions protruding from the protein's globular surface. The aim of this work was to implement that method as a web-tool and evaluate its performance on discontinuous epitopes known from the structures of antibody-protein complexes. Results Here we present ElliPro, a web-tool that implements Thornton's method and, together with a residue clustering algorithm, the MODELLER program and the Jmol viewer, allows the prediction and visualization of antibody epitopes in a given protein sequence or structure. ElliPro has been tested on a benchmark dataset of discontinuous epitopes inferred from 3D structures of antibody-protein complexes. In comparison with six other structure-based methods that can be used for epitope prediction, ElliPro performed the best and gave an AUC value of 0.732, when the most significant prediction was considered for each protein. Since the rank of the best prediction was at most in the top three for more than 70% of proteins and never exceeded five, ElliPro is considered a useful research tool for identifying antibody epitopes in protein antigens. ElliPro is available at http://tools.immuneepitope.org/tools/ElliPro. Conclusion The results from ElliPro suggest that further research on antibody epitopes considering more features that discriminate epitopes from non-epitopes may further improve predictions. As ElliPro is based on the geometrical properties of protein structure and does not require training, it might be more generally applied for predicting different types of protein-protein interactions.

  2. Linear B-cell epitopes in BthTX-1, BthTX-II and BthA-1, phospholipase A₂'s from Bothrops jararacussu snake venom, recognized by therapeutically neutralizing commercial horse antivenom.

    Science.gov (United States)

    De-Simone, Salvatore G; Napoleão-Pego, Paloma; Teixeira-Pinto, Luiz A L; Santos, Jonathas D L; De-Simone, Thatiane S; Melgarejo, Anibal R; Aguiar, Aniesse S; Marchi-Salvador, Daniela P

    2013-09-01

    The benefits from treatment with antivenom sera are indubitable. However, the mechanism for toxin neutralization has not been completely elucidated. A mixture of anti-bothropic and anti-crotalic horse antivenom has been reported to be more effective in neutralizing the effects of Bothrops jararacussu snake venom than anti-bothropic antivenom alone. This study determined which regions in the three PLA₂s from B. jararacussu snake venom are bound by antibodies in tetravalent anti-bothropic and monovalent anti-crotalic commercial horse antivenom. Mapping experiments of BthTX-I, BthTX-II and BthA-I using two small libraries of 69 peptides each revealed six major IgG-binding epitopes that were recognized by both anti-bothropic and anti-crotalic horse antivenom. Two epitopes in BthTX-I were only recognized by the anti-bothropic horse antivenom, while anti-crotalic horse antivenom recognized four unique epitopes across the three PLA₂s. Our studies suggest that the harmful activities of the PLA₂s present in the venom of B. jararacussu are neutralized by the combinatorial treatment with both antivenom sera through their complementary binding sites, which provides a wide coverage on the PLA₂s. This is the first peptide microarray of PLA₂s from B. jararacussu snake venom to survey the performance of commercial horse antiophidic antivenom. Regions recognized by the protective antivenom sera are prime candidates for improved venom cocktails or a chimeric protein encoding the multiple epitopes to immunize animals as well as for designing future synthetic vaccines. PMID:23792452

  3. Cloning,Sequencing,Secondary Structure and B-cell Epitopes Prediction of Bordetella avium Outer Membrane Protein OmpA%禽波氏杆菌外膜蛋白A的克隆测序与生物信息分析

    Institute of Scientific and Technical Information of China (English)

    谭燕玲; 朱瑞良; 王慧; 王新建; 魏凯; 孙振红; 盛鹏程

    2011-01-01

    The aims of this study was to clone and sequence the ompA gene of Bordetella avium,and predict its secondary structure and B-cell epitopes, which provides a theoretical basis for the study of immune mechanism and B. avium subunit vaccine. The B. avium ompA gene was amplified, cloned, and sequenced. By using bioinformatics softwares and methods, the secondary structure and B-cell preponderant epitope of B. avium OmpA were predicted. The results indicated that B. avium ompA gene is 597 bp, encoding 199 amino acids. Using three methods, prediction of the secondary structure of B. avium OmpA indicated that random coils were the main structural type of the flexible region in secondary structure, and contain a small amount of α-helix, β-sheet and a rare β-turn. The OmpA protein was supposed contain 5 potential antigen epitopes and 2 potential glycosylated sites. These results provide a theoretical basis for the further study of immune mechanisms, monoclonal antibodies preparation and epitope vaccine design.%本文旨在克隆禽波氏杆菌外膜蛋白OmpA的编码基因,并预测OmpA蛋白二级结构和B细胞抗原表位,从而探讨禽波氏杆菌外膜蛋白OmpA在免疫保护中所起的作用.作者对禽波氏杆菌的外膜蛋白ompA基因进行PCR扩增、克隆及序列测定.应用生物信息学相关软件和方法,对禽波氏杆菌OmpA蛋白的二级结构和B细胞抗原表位进行预测.禽波氏杆菌ompA基因全长597 bp,编码199个氨基酸.二级结构以无规卷曲为主,有少量的α-螺旋和β-片层,少见β-转角;推测OmpA蛋白有5个B细胞优势抗原表位区域、2个糖基化位点.本研究为进一步分析禽波氏杆菌免疫机理、制备单克隆抗体和设计表位疫苗等奠定理论基础.

  4. 空肠弯曲菌主要外膜蛋白 OMP18的B 细胞抗原表位分析及功能鉴定%Analysis and identification of B cell epitopes of the OMP18 from Campy lobacter jejuni

    Institute of Scientific and Technical Information of China (English)

    楼宏强; 胡野; 王岚; 单小云; 盛秀胜; 高素华

    2014-01-01

    目的:从生物信息学角度了解空肠弯曲菌主要外膜蛋白OM P18的跨膜结构、B细胞抗原表位及其抗原性、基因序列保守性等特征,并鉴定空肠弯曲菌主要外膜蛋白优势B细胞抗原表位,为后续抗体检测和疫苗研究提供实验依据。方法使用NCBI/Blast ,TMHMM Server V2.0,DNA Star等生物信息学分析软件对空肠弯曲菌主要外膜蛋白OMP18进行蛋白跨膜结构预测、线性B细胞抗原表位及其抗原性分析、并对不同空肠弯曲菌OM P18蛋白的氨基酸序列同源性进行比较。采用空肠弯曲菌全菌抗体IgG为一抗,基于ELISA技术对优势线性B细胞抗原表位进行筛选鉴定。结果生物信息学预测结果表明外膜蛋白OM P18定位于空肠弯曲菌外膜且不存在跨膜结构。蛋白序列保守存在于各空肠弯曲菌株中,序列同源性达95%以上。同时,我们发现该外膜蛋白中存在3个明显的B细胞线性表位,且具有很强的抗原性。ELISA检测鉴定结果表明3个B细胞抗原表位都能有效识别空肠弯曲菌全菌抗体。结论空肠弯曲菌主要外膜蛋白O M P18保守存在于细菌表面,存在3个重要的B细胞线性抗原表位,可用于后续的抗体检测和疫苗开发研究。%In this study ,we aimed to understand the sequence characteristics ,transmembrane structures ,line B cell epitopes present in the OMP18 from Campylobacter jejuni ,and provide candidate antigens for the antibody detection and vac-cine development .NCBI/Blast ,TMHMM Server V2 and DNA Star softwares were used for the OMP18 sequence analysis . Based on the ELISA ,the whole bacterial antibody IgG of Campylobacter jejuni was used for the identification of the predicted line B cell epitopes .The OMP18 gene was found conserved in different Campylobacter jejuni strains .The OMP18 was predic-ted to be located on the outer surface of the bacteria .And three line B cell epitopes were determined to be present in

  5. Design of targeted B cell killing agents.

    Directory of Open Access Journals (Sweden)

    Alexey V Stepanov

    Full Text Available B cells play an important role in the pathogenesis of both systemic and organ-specific autoimmune diseases. Autoreactive B cells not only produce autoantibodies, but also are capable to efficiently present specific autoantigens to T cells. Furthermore, B cells can secrete proinflammatory cytokines and amplify the vicious process of self-destruction. B cell-directed therapy is a potentially important approach for treatment of various autoimmune diseases. The depletion of B cells by anti-CD20/19 monoclonal antibody Retuximab® used in autoimmune diseases therapy leads to systemic side effects and should be significantly improved. In this study we designed a repertoire of genetically engineered B cell killers that specifically affected one kind of cells carrying a respective B cell receptor. We constructed immunotoxins (ITs, fused with c-myc epitope as a model targeting sequence, based on barnase, Pseudomonas toxin, Shiga-like toxin E.coli and Fc domain of human antibody IgGγ1. C-MYC hybridoma cell line producing anti-c-myc IgG was chosen as a model for targeted cell depletion. C-myc sequence fused with toxins provided addressed delivery of the toxic agent to the target cells. We demonstrated functional activity of designed ITs in vitro and showed recognition of the fusion molecules by antibodies produced by targeted hybridoma. To study specificity of the proposed B cells killing molecules, we tested a set of created ITs ex vivo, using C-MYC and irrelevant hybridoma cell lines. Pseudomonas-containing IT showed one of the highest cytotoxic effects on the model cells, however, possessed promiscuous specificity. Shiga-like toxin construct demonstrated mild both cytotoxicity and specificity. Barnase and Fc-containing ITs revealed excellent balance between their legibility and toxic properties. Moreover, barnase and Fc molecules fused with c-myc epitope were able to selectively deplete c-myc-specific B cells and decrease production of anti

  6. The Chikungunya Virus Capsid Protein Contains Linear B Cell Epitopes in the N- and C-Terminal Regions that are Dependent on an Intact C-Terminus for Antibody Recognition

    Directory of Open Access Journals (Sweden)

    Lucas Y. H. Goh

    2015-06-01

    Full Text Available Chikungunya virus (CHIKV is an arthropod-borne agent that causes severe arthritic disease in humans and is considered a serious health threat in areas where competent mosquito vectors are prevalent. CHIKV has recently been responsible for several millions of cases of disease, involving over 40 countries. The recent re-emergence of CHIKV and its potential threat to human health has stimulated interest in better understanding of the biology and pathogenesis of the virus, and requirement for improved treatment, prevention and control measures. In this study, we mapped the binding sites of a panel of eleven monoclonal antibodies (mAbs previously generated towards the capsid protein (CP of CHIKV. Using N- and C-terminally truncated recombinant forms of the CHIKV CP, two putative binding regions, between residues 1–35 and 140–210, were identified. Competitive binding also revealed that five of the CP-specific mAbs recognized a series of overlapping epitopes in the latter domain. We also identified a smaller, N-terminally truncated product of native CP that may represent an alternative translation product of the CHIKV 26S RNA and have potential functional significance during CHIKV replication. Our data also provides evidence that the C-terminus of CP is required for authentic antigenic structure of CP. This study shows that these anti-CP mAbs will be valuable research tools for further investigating the structure and function of the CHIKV CP.

  7. The Chikungunya Virus Capsid Protein Contains Linear B Cell Epitopes in the N- and C-Terminal Regions that are Dependent on an Intact C-Terminus for Antibody Recognition.

    Science.gov (United States)

    Goh, Lucas Y H; Hobson-Peters, Jody; Prow, Natalie A; Baker, Kelly; Piyasena, Thisun B H; Taylor, Carmel T; Rana, Ashok; Hastie, Marcus L; Gorman, Jeff J; Hall, Roy A

    2015-06-08

    Chikungunya virus (CHIKV) is an arthropod-borne agent that causes severe arthritic disease in humans and is considered a serious health threat in areas where competent mosquito vectors are prevalent. CHIKV has recently been responsible for several millions of cases of disease, involving over 40 countries. The recent re-emergence of CHIKV and its potential threat to human health has stimulated interest in better understanding of the biology and pathogenesis of the virus, and requirement for improved treatment, prevention and control measures. In this study, we mapped the binding sites of a panel of eleven monoclonal antibodies (mAbs) previously generated towards the capsid protein (CP) of CHIKV. Using N- and C-terminally truncated recombinant forms of the CHIKV CP, two putative binding regions, between residues 1-35 and 140-210, were identified. Competitive binding also revealed that five of the CP-specific mAbs recognized a series of overlapping epitopes in the latter domain. We also identified a smaller, N-terminally truncated product of native CP that may represent an alternative translation product of the CHIKV 26S RNA and have potential functional significance during CHIKV replication. Our data also provides evidence that the C-terminus of CP is required for authentic antigenic structure of CP. This study shows that these anti-CP mAbs will be valuable research tools for further investigating the structure and function of the CHIKV CP.

  8. Expression of T and B cells combined epitopes protein of Leptospira interrogans and the immunity analysis%问号钩端螺旋体T和B细胞表位联合基因的原核表达及其产物免疫性分析

    Institute of Scientific and Technical Information of China (English)

    丁士标; 李召东; 严杰; 林旭瑷

    2011-01-01

    目的 构建问号钩端螺旋体(简称钩体)LipL32、OmpL1和LipL21蛋白的优势T-和B-细胞联合表位融合基因及其原核表达系统,并对表达产物的免疫原性进行鉴定.方法 人工合成多表位联合基因并构建其原核表达系统.采用SDS-PAGE检测重组蛋白;采用MAT检测重组蛋白兔抗血清与我国钩体标准参考株的凝集效价;Western blot和ELISA检测重组蛋白的免疫原性.结果 获得了多表位融合基因并构建了原核表达系统.表达产物的相对分子质量约为23×103,且主要以可溶性形式存在;重组蛋白兔抗血清免疫双扩散效价为1∶8,该抗血清能与我国15群的钩体标准参考株发生凝集反应,ELISA证明该重组蛋白能检测不同群型钩体感染患者血清中的抗钩体抗体.结论 成功构建了包含钩体LipL32、OmpL1和LipL21蛋白的优势T和B细胞联合表位基因及其原核表达系统,表达产物具有良好的抗原性和交叉免疫反应性,可作为研制通用型问号钩体基因工程疫苗及血清学检测的抗原.%Objective To construct the T-cells and B-cells combined epitope peptide gene based on the LipL32,OmpL1 and LipL21 protein from Leptospira interrogans and E.coli expression system,and better understanding of the immunological activity of the recombinant protein. Methods The immunodomaint T- and B-cells combined epitopes of LipL32,OmpL1 and LipL21 were identified and used to synthetic a new gene and then construct its prokaryotic expression system.The expression of recombinant protein was determined by SDS-PAGE; MAT was used to determine the titer of the antiserum to L. interrogans standard strains of China ; Western blot and ELISA were used to identify the immunity activity of the recombinant protein.Results The synthetic gene was effectively expressed in E.coli BL21 ( DE3 ) strain and mainly presented in dissoluble protein.Western blot result showed that the expression protein react well with the

  9. Advances of Bioinformatics Tools Applied in Virus Epitopes Prediction

    Institute of Scientific and Technical Information of China (English)

    Ping Chen; Simon Rayner; Kang-hong Hu

    2011-01-01

    In recent years, the in silico epitopes prediction tools have facilitated the progress of vaccines development significantly and many have been applied to predict epitopes in viruses successfully. Herein, a general overview of different tools currently available, including T cell and B cell epitopes prediction tools, is presented. And the principles of different prediction algorithms are reviewed briefly. Finally, several examples are present to illustrate the application of the prediction tools.

  10. B Epitope Multiplicity and B/T Epitope Orientation Influence Immunogenicity of Foot-and-Mouth Disease Peptide Vaccines

    Directory of Open Access Journals (Sweden)

    Esther Blanco

    2013-01-01

    Full Text Available Synthetic peptides incorporating protective B- and T-cell epitopes are candidates for new safer foot-and-mouth disease (FMD vaccines. We have reported that dendrimeric peptides including four copies of a B-cell epitope (VP1 136 to 154 linked to a T-cell epitope (3A 21 to 35 of FMD virus (FMDV elicit potent B- and T-cell specific responses and confer protection to viral challenge, while juxtaposition of these epitopes in a linear peptide induces less efficient responses. To assess the relevance of B-cell epitope multivalency, dendrimers bearing two (B2T or four (B4T copies of the B-cell epitope from type O FMDV (a widespread circulating serotype were tested in CD1 mice and showed that multivalency is advantageous over simple B-T-epitope juxtaposition, resulting in efficient induction of neutralizing antibodies and optimal release of IFNγ. Interestingly, the bivalent B2T construction elicited similar or even better B- and T-cell specific responses than tetravalent B4T. In addition, the presence of the T-cell epitope and its orientation were shown to be critical for the immunogenicity of the linear juxtaposed monovalent peptides analyzed in parallel. Taken together, our results provide useful insights for a more accurate design of FMD subunit vaccines.

  11. 4种血清型登革病毒NS1蛋白序列及B细胞抗原表位特异性分析%Analysis on genome and amino acids sequence and B cell epitopes for 4 serotypes of dengue virus NS1 protein

    Institute of Scientific and Technical Information of China (English)

    陈艳佳; 熊建英; 朱利; 曹虹; 赵卫

    2013-01-01

    目的 比较4种血清型登革病毒NS1蛋白型特异性抗原表位基因序列及氨基酸序列之间的差异,为利用基因差异进行血清学分型及疫苗研究提供新的线索.方法 利用DNAstar数据包中的Editseq程序,从20株登革病毒分离株的全基因组序列中将NS1基因型特异性抗原表位序列截取出来,再用Clustal X软件进行多序列比对,进行同源性分析,找出型内最为保守的抗原表位序列.并将比对结果在120株登革病毒序列中进一步验证.结果 NS1蛋白36~45和71~85位氨基酸为型特异性抗原表位,高度保守,型内完全相同,型间不同.结论 NS1蛋白36~45位氨基酸可以作为登革病毒血清分型和研制亚单位疫苗的靶标.%OBJECTIVE To compare genome and amino acids sequences and possible B cell epitopes of 4 serotypes of dengue virus NS1 protein, to explore a new method of gene typing and provide new clues to vaccine research. METHODS Cut off the corresponding gene sequences of NS1 protein from the complete genome of 20 dengue virus isolates, then multisequencing was carried out to find the gene which was conservative within the same serotype and variant in the other serotypes. RESULTS Specific antigens of NS1 protein (36-45 and 71-85 amino acids) were conservative within the same serotype and variant in other serotypes. CONCLUSION Specific antigens of NS1 protein (36-45 amino acids) are the bases of dengue virus typing and targets of subunit vaccine development.

  12. Automatic Generation of Validated Specific Epitope Sets

    Directory of Open Access Journals (Sweden)

    Sebastian Carrasco Pro

    2015-01-01

    Full Text Available Accurate measurement of B and T cell responses is a valuable tool to study autoimmunity, allergies, immunity to pathogens, and host-pathogen interactions and assist in the design and evaluation of T cell vaccines and immunotherapies. In this context, it is desirable to elucidate a method to select validated reference sets of epitopes to allow detection of T and B cells. However, the ever-growing information contained in the Immune Epitope Database (IEDB and the differences in quality and subjects studied between epitope assays make this task complicated. In this study, we develop a novel method to automatically select reference epitope sets according to a categorization system employed by the IEDB. From the sets generated, three epitope sets (EBV, mycobacteria and dengue were experimentally validated by detection of T cell reactivity ex vivo from human donors. Furthermore, a web application that will potentially be implemented in the IEDB was created to allow users the capacity to generate customized epitope sets.

  13. Two highly similar LAEDDTNAQKT and LTDKIGTEI epitopes in G glycoprotein may be useful for effective epitope based vaccine design against pathogenic Henipavirus.

    Science.gov (United States)

    Parvege, Md Masud; Rahman, Monzilur; Nibir, Yead Morshed; Hossain, Mohammad Shahnoor

    2016-04-01

    Nipah virus and Hendra virus, two members of the genus Henipavirus, are newly emerging zoonotic pathogens which cause acute respiratory illness and severe encephalitis in human. Lack of the effective antiviral therapy endorses the urgency for the development of vaccine against these deadly viruses. In this study, we employed various computational approaches to identify epitopes which has the potential for vaccine development. By analyzing the immune parameters of the conserved sequences of G glycoprotein using various databases and bioinformatics tools, we identified two potential epitopes which may be used as peptide vaccines. Using different B cell epitope prediction servers, four highly similar B cell epitopes were identified. Immunoinformatics analyses revealed that LAEDDTNAQKT is a highly flexible and accessible B-cell epitope to antibody. Highly similar putative CTL epitopes were analyzed for their binding with the HLA-C 12*03 molecule. Docking simulation assay revealed that LTDKIGTEI has significantly lower binding energy, which bolstered its potential as epitope-based vaccine design. Finally, cytotoxicity analysis has also justified their potential as promising epitope-based vaccine candidate. In sum, our computational analysis indicates that either LAEDDTNAQKT or LTDKIGTEI epitope holds a promise for the development of universal vaccine against all kinds of pathogenic Henipavirus. Further in vivo and in vitro studies are necessary to validate the obtained findings.

  14. Expression and immunoreactivity of an epitope of HCV in a foreign epitope presenting system

    Institute of Scientific and Technical Information of China (English)

    Mei Peng; Chang-Bai Dai; Yuan-Ding Chen

    2005-01-01

    AIM: To construct and highly express an epitope of hepatitis C virus (HCV) in a foreign epitope presenting vectorbased on an insect virus, and to study the antigenicity of the epitope.METHODS: The HCV epitope sequence (amino acidresidues 315 to 328: EGHRMAWDMMMNWS) of the E1 region was constructed at different positions of a foreign epitope presenting vector based on an insect virus, flock house virus (FHV) capsid protein encoding gene as a vector, and expressed in E. coli cells. Western blottingand ELISA were used to detect the immunoreactivity of these recombinant proteins.RESULTS: The gene encoding of the concerned B-cell epitope of HCV E1 envelope protein was expressed on FHV capsid carrier protein at positions I1 (aa 106), I2 (aa153) and I3 (aa 305), respectively, on the surface of FHV capsid protein. The recombinant proteins in this system could be highly expressed in more than 40% of total cell protein of E. coli BL21. All the expressed recombinant proteins were in inclusion body form, and showed obvious immunoreactivity by Western blotting. Further purified recombinant proteins were detected by indirect ELISA as coating antigen respectively. All recombinant proteins could still show immunoreactivity.CONCLUSION: The epitope of HCV E1 envelope protein can be highly expressed in FHV carrier system as a chimeric protein with high immunoreactivity. This system has multiple entry sites conferring many possible conformations closer to the native one for a given sequence.

  15. Ibrutinib for B cell malignancies

    OpenAIRE

    Novero, Aileen; Ravella, Pavan M; Chen, Yamei; Dous, George; Liu, Delong

    2014-01-01

    Research over the role of Bruton’s agammaglobulinemia tyrosine kinase (BTK) in B-lymphocyte development, differentiation, signaling and survival has led to better understanding of the pathogenesis of B-cell malignancies. Down-regulation of BTK activity is an attractive novel strategy for treating patients with B-cell malignancies. Ibrutinib (PCI-32765), a potent inhibitor of BTK induces impressive responses in B-cell malignancies through irreversible bond with cysteine-481 in the active site ...

  16. Plasmodium vivax Promiscuous T-Helper Epitopes Defined and Evaluated as Linear Peptide Chimera Immunogens

    Science.gov (United States)

    Caro-Aguilar, Ivette; Rodríguez, Alexandra; Calvo-Calle, J. Mauricio; Guzmán, Fanny; De la Vega, Patricia; Elkin Patarroyo, Manuel; Galinski, Mary R.; Moreno, Alberto

    2002-01-01

    Clinical trials of malaria vaccines have confirmed that parasite-derived T-cell epitopes are required to elicit consistent and long-lasting immune responses. We report here the identification and functional characterization of six T-cell epitopes that are present in the merozoite surface protein-1 of Plasmodium vivax (PvMSP-1) and bind promiscuously to four different HLA-DRB1∗ alleles. Each of these peptides induced lymphoproliferative responses in cells from individuals with previous P. vivax infections. Furthermore, linear-peptide chimeras containing the promiscuous PvMSP-1 T-cell epitopes, synthesized in tandem with the Plasmodium falciparum immunodominant circumsporozoite protein (CSP) B-cell epitope, induced high specific antibody titers, cytokine production, long-lasting immune responses, and immunoglobulin G isotype class switching in BALB/c mice. A linear-peptide chimera containing an allele-restricted P. falciparum T-cell epitope with the CSP B-cell epitope was not effective. Two out of the six promiscuous T-cell epitopes exhibiting the highest anti-peptide response also contain B-cell epitopes. Antisera generated against these B-cell epitopes recognize P. vivax merozoites in immunofluorescence assays. Importantly, the anti-peptide antibodies generated to the CSP B-cell epitope inhibited the invasion of P. falciparum sporozoites into human hepatocytes. These data and the simplicity of design of the chimeric constructs highlight the potential of multimeric, multistage, and multispecies linear-peptide chimeras containing parasite promiscuous T-cell epitopes for malaria vaccine development. PMID:12065487

  17. Molecular modeling and conformational IgG epitope mapping on bovine β-casein

    NARCIS (Netherlands)

    Liu, Fahui; Gao, Jinyan; Li, Xin; Chen, Hongbing

    2016-01-01

    Characterizing conformational B-cell epitopes is a key step for understanding the immunological basis of allergy contributed by β-casein. There is no resolved conformational structure of β-casein in protein data bank, and most of the previous research on epitope identification of β-casein focused

  18. Virus-Like Particles of Chimeric Recombinant Porcine Circovirus Type 2 as Antigen Vehicle Carrying Foreign Epitopes

    OpenAIRE

    2014-01-01

    Virus-like particles (VLPs) of chimeric porcine circovirus type 2 (PCV2) were generated by replacing the nuclear localization signal (NLS; at 1–39 aa) of PCV2 capsid protein (Cap) with classical swine fever virus (CSFV) T-cell epitope (1446–1460 aa), CSFV B-cell epitope (693–716 aa) and CSFV T-cell epitope conjugated with B-cell epitope. The recombinant proteins were expressed using the baculovirus expression system and detected by immunoblotting and indirect immunofluorescence assay. The ab...

  19. Epitope-specific antibody levels in tuberculosis: biomarkers of protection, disease and response to treatment.

    Directory of Open Access Journals (Sweden)

    Graham H Bothamley

    2014-06-01

    Full Text Available Monoclonal antibodies restricted to Mycobacterium tuberculosis can measure epitope-specific antibody levels in a competition assay. Immunodominant epitopes were defined from clinical samples and related to the clinical spectrum of disease. Antibody to the immunodominant epitopes was associated with HLA-DR15. Occupational exposure showed a different response and was consistent with recognition of dormancy related proteins and protection despite exposure to tuberculosis. Studies in leprosy revealed the importance of immune deviation and the relationships between T and B cell epitopes. During treatment, antibody levels increased, epitope spreading occurred, but the affinity constants remained the same after further antigen exposure, suggesting constraints on the process of epitope selection. Epitope-specific antibody levels have a potential role as biomarkers for new vaccines which might prevent the progression of latent to active tuberculosis and as tools to measure treatment effects on subpopulations of tubercle bacilli.

  20. Some epitopes conservation in non structural 3 protein dengue virus serotype 4

    Directory of Open Access Journals (Sweden)

    Tegar A. P. Siregar

    2016-03-01

    Full Text Available AbstrakLatar belakang: Protein Non Struktural 3 (NS3 virus dengue menginduksi respon antibodi netralisasidan respon sel T CD4+ dan CD8+, serta berperan dalam replikasi virus. Protein NS3 memiliki epitopepitopsel T dan B yang terdapat perbedaan kelestarian pada berbagai strain virus dengue serotipe 4(DENV-4. Penelitian ini bertujuan untuk mengetahui kelestarian epitop sel T dan B pada protein NS3DENV-4 strain-strain dunia dan keempat serotipe virus dengue strain Indonesia.Metode: Penelitian ini dilakukan di Departemen Mikrobiologi Fakultas Kedokteran UI sejak Juni 2013 - April2014. Sekuens asam amino NS3 DENV-4 strain 081 didapatkan setelah produk PCR gen NS3 DENV-4 081disekuensing. Epitop-epitop sel T dan sel B protein NS3 DENV-4 081 dianalisis dan dibandingkan dengansekuens asam amino protein NS3 dari 124 strain DENV-4 di dunia dan keempat serotipe DENV strain Indonesia.Strain-strain dunia merupakan strain yang ada di benua Amerika (Venezuela, Colombia, dll dan Asia (Cina,Singapura, dll. Referensi posisi epitop sel T dan B protein NS3 diperoleh dari laporan penelitian terdahulu.Hasil: Delapan epitop sel T dan 2 epitop sel B dari protein NS3 DENV-4 081 ternyata identik dan lestaripada protein NS3 dari 124 strain DENV-4 dunia. Epitop sel B di posisi asam amino 537-544 pada proteinNS3 DENV-4 081 ternyata identik dan lestari dengan epitop sel B protein NS3 dari keempat serotipeDENV strain Indonesia.Kesimpulan: Kelestarian yang luas dari epitop sel T dan B pada hampir seluruh strain DENV-4 dunia danserotipe-serotipe DENV strain Indonesia. (Health Science Journal of Indonesia 2015;6:126-31Kata kunci: virus dengue, protein NS3, epitop sel T, epitop sel B AbstractBackground: Non Structural 3 (NS3 protein of dengue virus (DENV is known to induce antibody, CD4+and CD8+ T cell responses, and playing role in viral replication. NS3 protein has T and B cell epitopes,which has conservation difference between DENV-4 strains. This study aimed to identify

  1. Dominant epitopes and allergic cross-reactivity

    DEFF Research Database (Denmark)

    Mirza, Osman Asghar; Henriksen, A; Ipsen, H;

    2000-01-01

    as defined by the Bet v 1 Ab interaction surface. Molecular interactions predicted to occur in the interface are likewise in agreement with earlier observations on Ag-Ab complexes. The epitope is formed by amino acids that are conserved among major allergens from related species within the Fagales order......The symptoms characteristic of allergic hypersensitivity are caused by the release of mediators, i.e., histamine, from effector cells such as basophils and mast cells. Allergens with more than one B cell epitope cross-link IgE Abs bound to high affinity FcepsilonRI receptors on mast cell surfaces...... leading to aggregation and subsequent mediator release. Thus, allergen-Ab complexes play a crucial role in the cascade leading to the allergic response. We here report the structure of a 1:1 complex between the major birch pollen allergen Bet v 1 and the Fab fragment from a murine monoclonal IgG1 Ab, BV16...

  2. Immunogenicity of multiple antigen peptides containing Plasmodium vivax CS epitopes in BALB/c mice

    Directory of Open Access Journals (Sweden)

    Myriam A. Herrera

    1994-01-01

    Full Text Available Multiple antigen peptide systems (MAPs allow the incorporation of various epitopes in to a single synthetic peptide immunogen. We have characterized the immune response of BALB/c mice to a series of MAPs assembled with different B and T cell epitopes derived from the Plasmodium vivax circumsporozoite (CS protein. A B-cell epitope from the central repeat domain and two T-cell epitopes from the amino and carboxyl flanking regions were used to assembled eight different MAPs. An additional universal T cell epitope (ptt-30 from tetanus toxin protein was included. Immunogenicity in terms of antibody responses and in vitro T lymphocyte proliferation was evaluated. MAPs containing B and T cell epitopes induced high titers of anti-peptides antibodies, which recognized the native protein on sporozoites as determined by IFAT. The antibody specificity was also determined by a competitive inhibition assay with different MAPs. A MAP containing the B cell epitope (p11 and the universal epitope ptt-30 together with another composed of p11 and the promiscuous T cell epitope (p25 proved to be the most immunogenic. The strong antibody response and specificity for the cognate protein indicates that further studies designed to assess the potential of these proteins as human malaria vaccine candidates are warranted.

  3. Prevention and control of reciprocal T-B cell diversification: implications for lupus-like autoimmunity.

    Science.gov (United States)

    Singh, Ram Raj

    2004-02-01

    Autoimmunity is fundamentally a continuously evolving process. The autoimmune responses shift, drift and diversify with time not only to other epitopes in the original antigen but also to other related and sometimes to unrelated antigens. We have described a form of immune diversification--reciprocal T-B epitope spreading--where the activation of first T cells by epitopes from an autoantibody molecule could lead to help provided to a variety of B cells displaying a cross-reactive version of the original epitope. The response spreads in this way until large cohorts of T and B cells have expanded in lupus-prone mice. Such reciprocal T-B cell response can also be induced in normal animals, its extent is limited by the emergence of inhibitory T cells. The induction of such inhibitory T cells is generally impaired in lupus mice. The delivery of T cell epitopes via plasmid DNA vectors, however, can overcome this impairment in lupus mice. The inhibitory T cells thus induced can suppress autoantibody production and lupus disease by ablating or inhibiting autoreactive B cells. Thus, T-B diversification that develops spontaneously in lupus mice could be curtailed in normal animals by inhibitory T cells that emerge whenever there is an impending 'danger' of pathologic autoimmunity. We have successfully exploited this regulatory potential of the normal immune response to inhibit clinical autoimmunity. Understanding the mechanisms of autoimmune diversification in lupus mice and of its down-regulation in normal animals may pave the way for developing novel treatments for autoantibody-mediated diseases such as lupus.

  4. Benchmark selection

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Tvede, Mich

    2002-01-01

    Within a production theoretic framework, this paper considers an axiomatic approach to benchmark selection. It is shown that two simple and weak axioms; efficiency and comprehensive monotonicity characterize a natural family of benchmarks which typically becomes unique. Further axioms are added...

  5. Interactive benchmarking

    DEFF Research Database (Denmark)

    Lawson, Lartey; Nielsen, Kurt

    2005-01-01

    We discuss individual learning by interactive benchmarking using stochastic frontier models. The interactions allow the user to tailor the performance evaluation to preferences and explore alternative improvement strategies by selecting and searching the different frontiers using directional...... in the suggested benchmarking tool. The study investigates how different characteristics on dairy farms influences the technical efficiency....

  6. Computational Analysis of Cysteine Proteases(Clan CA, Family C1)of Leishmania major to Find Potential Epitopic Regions

    Institute of Scientific and Technical Information of China (English)

    Babak Saffari; Hassan Mohabatkar

    2009-01-01

    Leishmania is associated with a broad spectrum of diseases, ranging from simple cutaneous to invasive visceral leishmaniasis. Here, the sequences of ten cysteine proteases of types A, B and C of Leishmania major were obtained from GeneDB database. Prediction of MHC class I epitopes of these cysteine proteases was per-formed by NetCTL program version 1.2. In addition, by using BcePred server, different structural properties of the proteins were predicted to find out their po-tential B cell epitopes. According to this computational analysis, nine regions were predicted as B cell epitopes. The results provide useful information for designing peptide-based vaccines.

  7. Thyrotropin Receptor Epitope and Human Leukocyte Antigen in Graves' Disease.

    Science.gov (United States)

    Inaba, Hidefumi; De Groot, Leslie J; Akamizu, Takashi

    2016-01-01

    Graves' disease (GD) is an organ-specific autoimmune disease, and thyrotropin (TSH) receptor (TSHR) is a major autoantigen in this condition. Since the extracellular domain of human TSHR (TSHR-ECD) is shed into the circulation, TSHR-ECD is a preferentially immunogenic portion of TSHR. Both genetic factors and environmental factors contribute to development of GD. Inheritance of human leukocyte antigen (HLA) genes, especially HLA-DR3, is associated with GD. TSHR-ECD protein is endocytosed into antigen-presenting cells (APCs), and processed to TSHR-ECD peptides. These peptide epitopes bind to HLA-class II molecules, and subsequently the complex of HLA-class II and TSHR-ECD epitope is presented to CD4+ T cells. The activated CD4+ T cells secrete cytokines/chemokines that stimulate B-cells to produce TSAb, and in turn hyperthyroidism occurs. Numerous studies have been done to identify T- and B-cell epitopes in TSHR-ECD, including (1) in silico, (2) in vitro, (3) in vivo, and (4) clinical experiments. Murine models of GD and HLA-transgenic mice have played a pivotal role in elucidating the immunological mechanisms. To date, linear or conformational epitopes of TSHR-ECD, as well as the molecular structure of the epitope-binding groove in HLA-DR, were reported to be related to the pathogenesis in GD. Dysfunction of central tolerance in the thymus, or in peripheral tolerance, such as regulatory T cells, could allow development of GD. Novel treatments using TSHR antagonists or mutated TSHR peptides have been reported to be effective. We review and update the role of immunogenic TSHR epitopes and HLA in GD, and offer perspectives on TSHR epitope specific treatments. PMID:27602020

  8. Repeated epitope in the recombinant epitope-peptide could enhance ELDKWA-epitope-specific antibody response

    Institute of Scientific and Technical Information of China (English)

    LIU Zuqiang; WANG Zuguang; CHEN Yinghua

    2005-01-01

    Based on the hypothesis suggested by us that epitope-vaccine may be a new strategy against HIV mutation, we have studied several neutralizing epitopes on HIV envelope proteins. However we do not know whether a repeated epitope in a recombinant epitope-peptide can enhance epitope-specific antibody response or not. ELDKWA-epitope (aa669-674) on the C-domain of HIV-1 gp41 is a neutralizing epitope defined by the monoclonal antibody (mAb) 2F5 with broad neutralizing activity. In this study, we designed and prepared a series of the recombinant epitope-peptides bearing 1, 4 and 8 copies of ELDKWA-epitope respectively. In the comparison of the antisera induced by the three recombinant antigens, an obviously increased titre of ELDKWA-epitope-specific antibody was observed in the case of four and eight repeated epitopes. In flow cytometry analysis, the epitope-specific antibodies in both antisera showed stronger activity to bind the transfected CHO-WT cells that stably express HIV-1 envelope glycoprotein on the cell surfaces. These experimental results indicated that repeated epitope in the recombinant epitope-peptide could enhance ELDKWA-epitope-specific antibody response, which could contribute to designing an effective recombinant epitope-vaccine.

  9. Human Antibodies that Recognize Novel Immunodominant Quaternary Epitopes on the HIV-1 Env Protein.

    Directory of Open Access Journals (Sweden)

    Mark D Hicar

    Full Text Available Numerous broadly neutralizing antibodies (Abs target epitopes that are formed or enhanced during mature HIV envelope formation (i.e. quaternary epitopes. Generally, it is thought that Env epitopes that induce broadly neutralizing Abs are difficult to access and poorly immunogenic because of the characteristic oligomerization, conformational flexibility, sequence diversity and extensive glycosylation of Env protein. To enhance for isolation of quaternary epitope-targeting Abs (QtAbs, we previously used HIV virus-like particles (VLPs to bind B cells from long-term non-progressor subjects to identify a panel of monoclonal Abs. When expressed as recombinant full-length Abs, a subset of these novel Abs exhibited the binding profiles of QtAbs, as they either failed to bind to monomeric Env protein or showed much higher affinity for Env trimers and VLPs. These QtAbs represented a significant proportion of the B-cell response identified with VLPs. The Ab genes of these clones were highly mutated, but they did not neutralize common HIV strains. We sought to further define the epitopes targeted by these QtAbs. Competition-binding and mapping studies revealed these Abs targeted four separate epitopes; they also failed to compete for binding by Abs to known major neutralizing epitopes. Detailed epitope mapping studies revealed that two of the four epitopes were located in the gp41 subunit of Env. These QtAbs bound pre-fusion forms of antigen and showed differential binding kinetics depending on whether oligomers were produced as recombinant gp140 trimers or as full-length Env incorporated into VLPs. Antigenic regions within gp41 present unexpectedly diverse structural epitopes, including these QtAb epitopes, which may be targeted by the naturally occurring Ab response to HIV infection.

  10. Human Antibodies that Recognize Novel Immunodominant Quaternary Epitopes on the HIV-1 Env Protein.

    Science.gov (United States)

    Hicar, Mark D; Chen, Xuemin; Sulli, Chidananda; Barnes, Trevor; Goodman, Jason; Sojar, Hakimuddin; Briney, Bryan; Willis, Jordan; Chukwuma, Valentine U; Kalams, Spyros A; Doranz, Benjamin J; Spearman, Paul; Crowe, James E

    2016-01-01

    Numerous broadly neutralizing antibodies (Abs) target epitopes that are formed or enhanced during mature HIV envelope formation (i.e. quaternary epitopes). Generally, it is thought that Env epitopes that induce broadly neutralizing Abs are difficult to access and poorly immunogenic because of the characteristic oligomerization, conformational flexibility, sequence diversity and extensive glycosylation of Env protein. To enhance for isolation of quaternary epitope-targeting Abs (QtAbs), we previously used HIV virus-like particles (VLPs) to bind B cells from long-term non-progressor subjects to identify a panel of monoclonal Abs. When expressed as recombinant full-length Abs, a subset of these novel Abs exhibited the binding profiles of QtAbs, as they either failed to bind to monomeric Env protein or showed much higher affinity for Env trimers and VLPs. These QtAbs represented a significant proportion of the B-cell response identified with VLPs. The Ab genes of these clones were highly mutated, but they did not neutralize common HIV strains. We sought to further define the epitopes targeted by these QtAbs. Competition-binding and mapping studies revealed these Abs targeted four separate epitopes; they also failed to compete for binding by Abs to known major neutralizing epitopes. Detailed epitope mapping studies revealed that two of the four epitopes were located in the gp41 subunit of Env. These QtAbs bound pre-fusion forms of antigen and showed differential binding kinetics depending on whether oligomers were produced as recombinant gp140 trimers or as full-length Env incorporated into VLPs. Antigenic regions within gp41 present unexpectedly diverse structural epitopes, including these QtAb epitopes, which may be targeted by the naturally occurring Ab response to HIV infection. PMID:27411063

  11. Multiple Curricula for B Cell Developmental Programming.

    Science.gov (United States)

    Rothenberg, Ellen V

    2016-09-20

    B-1 B cells differ from conventional B-2 B cells functionally, but how these differences relate to the ontogeny of these lineages has been unclear. Two recent Immunity articles, Kristiansen et al. (2016) and Montecino-Rodriguez et al. (2016), now provide insight into the origins of B-1 and B-2 B cells, revealing a multi-layered developmental program and successive waves of B cell precursors.

  12. New helping friends for B cells.

    OpenAIRE

    Cerutti, Andrea; Puga, Irene; Cols, Montserrat

    2012-01-01

    Over the past decade, a growing recognition of the importance of neutralizing antibodies in host defense combined with the success of B-cell depletion therapies in treating autoimmune disorders has led to an increased focus on better understanding the pathways underpinning B-cell antibody production. In general, B cells require cognate interaction with T helper cells in the germinal center of lymphoid follicles to generate protective antibodies. However, recent evidence shows that B cells rec...

  13. Multiple Curricula for B Cell Developmental Programming.

    Science.gov (United States)

    Rothenberg, Ellen V

    2016-09-20

    B-1 B cells differ from conventional B-2 B cells functionally, but how these differences relate to the ontogeny of these lineages has been unclear. Two recent Immunity articles, Kristiansen et al. (2016) and Montecino-Rodriguez et al. (2016), now provide insight into the origins of B-1 and B-2 B cells, revealing a multi-layered developmental program and successive waves of B cell precursors. PMID:27653594

  14. B Cell Autonomous TLR Signaling and Autoimmunity

    Science.gov (United States)

    Meyer-Bahlburg, Almut; Rawlings, David J

    2009-01-01

    B cells play a central role in the pathogenesis of multiple autoimmune diseases and the recognition of importance of B cells in these disorders has grown dramatically in association with the remarkable success of B-cell depletion as a treatment for autoimmunity. The precise mechanisms that promote alterations in B cell tolerance remain incompletely defined. There is increasing evidence, however, that TLRs play a major role in these events. Stimulation of B cells via the TLR pathway not only leads to an increase in antibody production but also promotes additional changes including cytokine production and upregulation of activation markers increasing the effectiveness of B cells as APCs. Understanding the role of TLRs in systemic autoimmunity will not only provide insight into the disease pathogenesis but may also lead to the development of novel therapies. This article gives an overview of TLR signaling in B cells and the possible involvement of such signals in autoimmune diseases. PMID:18295736

  15. HCV Infection and B-Cell Lymphomagenesis

    Directory of Open Access Journals (Sweden)

    Masahiko Ito

    2011-01-01

    Full Text Available Hepatitis C virus (HCV has been recognized as a major cause of chronic liver diseases worldwide. It has been suggested that HCV infects not only hepatocytes but also mononuclear lymphocytes including B cells that express the CD81 molecule, a putative HCV receptor. HCV infection of B cells is the likely cause of B-cell dysregulation disorders such as mixed cryoglobulinemia, rheumatoid factor production, and B-cell lymphoproliferative disorders that may evolve into non-Hodgkin's lymphoma (NHL. Epidemiological data indicate an association between HCV chronic infection and the occurrence of B-cell NHL, suggesting that chronic HCV infection is associated at least in part with B-cell lymphomagenesis. In this paper, we aim to provide an overview of recent literature, including our own, to elucidate a possible role of HCV chronic infection in B-cell lymphomagenesis.

  16. P. falciparum and P. vivax Epitope-Focused VLPs Elicit Sterile Immunity to Blood Stage Infections.

    Directory of Open Access Journals (Sweden)

    David C Whitacre

    Full Text Available In order to design P. falciparum preerythrocytic vaccine candidates, a library of circumsporozoite (CS T and B cell epitopes displayed on the woodchuck hepatitis virus core antigen (WHcAg VLP platform was produced. To test the protective efficacy of the WHcAg-CS VLPs, hybrid CS P. berghei/P. falciparum (Pb/Pf sporozoites were used to challenge immunized mice. VLPs carrying 1 or 2 different CS repeat B cell epitopes and 3 VLPs carrying different CS non-repeat B cell epitopes elicited high levels of anti-insert antibodies (Abs. Whereas, VLPs carrying CS repeat B cell epitopes conferred 98% protection of the liver against a 10,000 Pb/Pf sporozoite challenge, VLPs carrying the CS non-repeat B cell eptiopes were minimally-to-non-protective. One-to-three CS-specific CD4/CD8 T cell sites were also fused to VLPs, which primed CS-specific as well as WHcAg-specific T cells. However, a VLP carrying only the 3 T cell domains failed to protect against a sporozoite challenge, indicating a requirement for anti-CS repeat Abs. A VLP carrying 2 CS repeat B cell epitopes and 3 CS T cell sites in alum adjuvant elicited high titer anti-CS Abs (endpoint dilution titer >1x10(6 and provided 80-100% protection against blood stage malaria. Using a similar strategy, VLPs were constructed carrying P. vivax CS repeat B cell epitopes (WHc-Pv-78, which elicited high levels of anti-CS Abs and conferred 99% protection of the liver against a 10,000 Pb/Pv sporozoite challenge and elicited sterile immunity to blood stage infection. These results indicate that immunization with epitope-focused VLPs carrying selected B and T cell epitopes from the P. falciparum and P. vivax CS proteins can elicit sterile immunity against blood stage malaria. Hybrid WHcAg-CS VLPs could provide the basis for a bivalent P. falciparum/P. vivax malaria vaccine.

  17. Virus-Like Display of a Neo-Self Antigen Reverses B Cell Anergy in a B Cell Receptor Transgenic Mouse Model1

    Science.gov (United States)

    Chackerian, Bryce; Durfee, Marisa R.; Schiller, John T.

    2012-01-01

    The ability to distinguish between self and foreign Ags is a central feature of immune recognition. For B cells, however, immune tolerance is not absolute, and factors that include Ag valency, the availability of T help, and polyclonal B cell stimuli can influence the induction of autoantibody responses. Here, we evaluated whether multivalent virus-like particle (VLP)-based immunogens could induce autoantibody responses in well-characterized transgenic (Tg) mice that express a soluble form of hen egg lysozyme (HEL) and in which B cell tolerance to HEL is maintained by anergy. Immunization with multivalent VLP-arrayed HEL, but not a trivalent form of HEL, induced high-titer Ab responses against HEL in both soluble HEL Tg mice and double Tg mice that also express a monoclonal HEL-specific BCR. Induction of autoantibodies against HEL was not dependent on coadministration of strong adjuvants, such as CFA. In contrast to previous data showing the T-independent induction of Abs to foreign epitopes on VLPs, the ability of HEL-conjugated VLPs to induce anti-HEL Abs in tolerant mice was dependent on the presence of CD4+ Th cells, and could be enhanced by the presence of pre-existing cognate T cells. In in vitro studies, VLP-conjugated HEL was more potent than trivalent HEL in up-regulating surface activation markers on purified anergic B cells. Moreover, immunization with VLP-HEL reversed B cell anergy in vivo in an adoptive transfer model. Thus, Ag multivalency and T help cooperate to reverse B cell anergy, a major mechanism of B cell tolerance. PMID:18424700

  18. Innate B cells: oxymoron or validated concept?

    OpenAIRE

    Ware, Carl F.; Chris Benedict

    2012-01-01

    B lymphocytes promote the initial innate interferon response to viral pathogens without the need for antigen receptor activation. B cell dependent IFN production requires the cytokine, lymphotoxin-β. The LTβ pathway is well known to regulate lymphoid organogenesis and homeostasis by differentiating stromal cells and macrophages. However, in response to viral pathogens these same B cell-regulated populations rapidly produce type 1 interferons. Thus, B cells act as innate effector cells via LTβ...

  19. B-Cell Hematologic Malignancy Vaccination Registry

    Science.gov (United States)

    2015-09-15

    Monoclonal Gammopathy of Undetermined Significance; Multiple Myeloma; Waldenstrom Macroglobulinemia; Lymphocytosis; Lymphoma, Non-Hodgkin; B-Cell Chronic Lymphocytic Leukemia; Hematological Malignancies

  20. Tolerogenicity of resting and activated B cells

    OpenAIRE

    1994-01-01

    Antigen presentation by resting splenic B cells has been shown previously to induce T helper 1 cell (Th1) anergy. In contrast to expectations, it was found here that B cells treated with F(ab')2 goat anti-mouse immunoglobulin (IgM) for 24 or 48 h also presented antigen (Ag) to Th1 cells in a manner that induced dramatic Ag-specific proliferative inactivation. The tolerogenicity of the anti-Ig-treated B cells was consistent with the observation that these B cells were only slightly more effici...

  1. Comprehensive Mapping Antigenic Epitopes of NS1 Protein of Japanese Encephalitis Virus with Monoclonal Antibodies.

    Directory of Open Access Journals (Sweden)

    Rong-Hong Hua

    Full Text Available Japanese encephalitis virus (JEV non-structural protein 1 (NS1 contributes to virus replication and elicits protective immune responses during infection. JEV NS1-specific antibody responses could be a target in the differential diagnosis of different flavivirus infections. However, the epitopes on JEV NS1 are poorly characterized. The present study describes the full mapping of linear B-cell epitopes in JEV NS1. We generated eleven NS1-specific monoclonal antibodies from mice immunized with recombinant NS1. For epitope mapping of monoclonal antibodies, a set of 51 partially-overlapping peptides covering the entire NS1 protein were expressed with a GST-tag and then screened using monoclonal antibodies. Through enzyme-linked immunosorbent assay (ELISA, five linear epitope-containing peptides were identified. By sequentially removing amino acid residues from the carboxy and amino terminal of peptides, the minimal units of the five linear epitopes were identified and confirmed using monoclonal antibodies. Five linear epitopes are located in amino acids residues (5AIDITRK(11, (72RDELNVL(78, (251KSKHNRREGY(260, (269DENGIVLD(276, and (341DETTLVRS(348. Furthermore, it was found that the epitopes are highly conserved among JEV strains through sequence alignment. Notably, none of the homologous regions on NS1 proteins from other flaviviruses reacted with the MAbs when they were tested for cross-reactivity, and all five epitope peptides were not recognized by sera against West Nile virus or Dengue virus. These novel virus-specific linear B-cell epitopes of JEV NS1 would benefit the development of new vaccines and diagnostic assays.

  2. Identification of a variant antigenic neutralizing epitope in hypervariable region 1 of avian leukosis virus subgroup J.

    Science.gov (United States)

    Hou, Minbo; Zhou, Defang; Li, Gen; Guo, Huijun; Liu, Jianzhu; Wang, Guihua; Zheng, Qiankun; Cheng, Ziqiang

    2016-03-01

    Avian leukosis virus subgroup J (ALV-J) is a hypervariable oncogenic retrovirus that causes great economic loss in poultry. Antigenic variations in the variable regions make the development of an effective vaccine a challenging task. In the present study, we identified a variant antigenic neutralizing epitope using reverse vaccinology methods. First, we predicted the B-cell epitopes in gp85 gene of ALV-J strains by DNAman and bioinformatics. Fourteen candidate epitopes were selected and linked in tandem with glycines or serines as a multi-epitope gene. The expressed protein of multi-epitope gene can induce high-titer antibody that can recognize nature ALV-J and neutralize the infectivity of ALV-J strains. Next, we identified a high effective epitope using eight overlapping fragments of gp85 gene reacting with mAb 2D5 and anti-multi-epitope sera. The identified epitope contained one of the predicted epitopes and localized in hyervariable region 1 (hr1), indicating a variant epitope. To better understand if the variants of the epitope have a good antigenicity, we synthesized four variants to react with mAb 2D5 and anti-ALV-J sera. The result showed that all variants could react with the two kinds of antibodies though they showed different antigenicity, while could not react with ALV-J negative sera. Thus, the variant antigenic neutralizing epitope was determined as 137-LRDFIA/E/TKWKS/GDDL/HLIRPYVNQS-158. The result shows a potential use of this variant epitopes as a novel multi-epitope vaccine against ALV-J in poultry.

  3. Epitope prediction methods

    DEFF Research Database (Denmark)

    Karosiene, Edita

    leucocyte antigen (HLA) molecules, are encoded by extremely polymorphic genes on chromosome 6. Due to this polymorphism, thousands of different MHC molecules exist, making the experimental identification of peptide-MHC interactions a very costly procedure. This has primed the need for in silico peptide......-MHC prediction methods, and over the last decade several such methods have been successfully developed and used for epitope discovery purposes. My PhD project has been dedicated to improve methods for predicting peptide-MHC interactions by developing new strategies for training prediction algorithms based...... on machine learning techniques. Several MHC class I binding prediction algorithms have been developed and due to their high accuracy they are used by many immunologists to facilitate the conventional experimental process of epitope discovery. However, the accuracy of these methods depends on data defining...

  4. Human Peripheral Blood B-Cell Compartments : A Crossroad in B-Cell Traffic

    NARCIS (Netherlands)

    Perez-Andres, M.; Paiva, B.; Nieto, W. G.; Caraux, A.; Schmitz, A.; Almeida, J.; Vogt, R. F.; Marti, G. E.; Rawstron, A. C.; Van Zelm, M. C.; Van Dongen, J. J. M.; Johnsen, H. E.; Klein, B.; Orfao, A.

    2010-01-01

    A relatively high number of different subsets of B-cells are generated through the differentiation of early B-cell precursors into mature B-lymphocytes in the bone marrow (BM) and antigen-triggered maturation of germinal center B-cells into memory B-lymphocytes and plasmablasts in lymphoid tissues.

  5. B Cells and Autoantibodies in Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Anne-Katrin Pröbstel

    2015-07-01

    Full Text Available While over the past decades T cells have been considered key players in the pathogenesis of multiple sclerosis (MS, it has only recently become evident that B cells have a major contributing role. Our understanding of the role of B cells has evolved substantially following the clinical success of B cell-targeting therapies and increasing experimental evidence for significant B cell involvement. Rather than mere antibody-producing cells, it is becoming clear that they are team players with the capacity to prime and regulate T cells, and function both as pro- and anti-inflammatory mediators. However, despite tremendous efforts, the target antigen(s of B cells in MS have yet to be identified. The first part of this review summarizes the clinical evidence and results from animal studies pointing to the relevance of B cells in the pathogenesis of MS. The second part gives an overview of the currently known potential autoantigen targets. The third part recapitulates and critically appraises the currently available B cell-directed therapies.

  6. Differential radiosensitivity among B cell subpopulations

    Energy Technology Data Exchange (ETDEWEB)

    Riggs, J.E.; Lussier, A.M.; Lee, S.K.; Appel, M.C.; Woodland, R.T.

    1988-09-15

    We have previously shown that low doses of ionizing radiation selectively impair a functionally defined B cell subpopulation. Normal mice, after exposure to 200 rad of ionizing radiation, have normal or near normal splenic plaque-forming cell responses to thymus-independent type 1 Ag, but reduced responses to thymus-independent type 2 Ag. Here, we confirm and extend the original findings by using hapten-specific serum RIA to demonstrate this differential radiosensitivity is systemic. We also examined splenocytes stained with a panel of lymphocyte surface Ag by FACS analysis to determine if these functional changes are accompanied by a physical alteration of the B cell pool of irradiated mice. Single-parameter FACS analyses demonstrate a diminution in both B cell number and the heterogeneity of membrane Ag expression within the surviving B cell pool after irradiation. In contrast, T cells are relatively radioresistant as the relative percentage of T cells in the irradiated splenocyte pool increases, whereas the heterogeneity of membrane Ag expression remains constant. Multiparameter FACS analyses indicate that B cells with the sIgM much greater than sIgD phenotype are more radiosensitive than B cells of the sIgM much less than sIgD phenotype. In addition, immunohistochemical analysis of splenic sections stained with anti-IgM or anti-IgD reveal the enhanced radiosensitivity of marginal zone B cells.

  7. B Cell Tolerance in Health and Disease

    Directory of Open Access Journals (Sweden)

    Murali Gururajan

    2014-02-01

    Full Text Available B lymphocyte receptors are generated randomly during the bone marrow developmental phase of B cells. Hence, the B cell repertoire consists of both self and foreign antigen specificities necessitating specific tolerance mechanisms to eliminate self-reactive B cells. This review summarizes the major mechanisms of B cell tolerance, which include clonal deletion, anergy and receptor editing. In the bone marrow presentation of antigen in membrane bound form is more effective than soluble form and the role of dendritic cells in this process is discussed. Toll like receptor derived signals affect activation of B cells by certain ligands such as nucleic acids and have been shown to play crucial roles in the development of autoimmunity in several animal models. In the periphery availability of BAFF, a B cell survival factor plays a critical role in the survival of self-reactive B cells. Antibodies against BAFF have been found to be effective therapeutic agents in lupus like autoimmune diseases. Recent developments are targeting anergy to control the growth of chronic lymphocytic leukemia cells.

  8. Prediction of promiscuous epitopes in the e6 protein of three high risk human papilloma viruses: a computational approach.

    Science.gov (United States)

    Subramanian, Nirmala; Chinnappan, Sudandiradoss

    2013-01-01

    A najor current challenge and constraint in cervical cancer research is the development of vaccines against human papilloma virus (HPV) epitopes. Although many studies are done on epitope identification on HPVs, no computational work has been carried out for high risk forms which are considered to cause cervical cancer. Of all the high risk HPVs, HPV 16, HPV 18 and HPV 45 are responsible for 94% of cervical cancers in women worldwide. In this work, we computationally predicted the promiscuous epitopes among the E6 proteins of high risk HPVs. We identified the conserved residues, HLA class I, HLA class II and B-cell epitopes along with their corresponding secondary structure conformations. We used extremely precise bioinformatics tools like ClustalW2, MAPPP, NetMHC, EpiJen, EpiTop 1.0, ABCpred, BCpred and PSIPred for achieving this task. Our study identified specific regions 'FAFR(K)DL' followed by 'KLPD(Q)LCTEL' fragments which proved to be promiscuous epitopes present in both human leukocyte antigen (HLA) class I, class II molecules and B cells as well. These fragments also follow every suitable character to be considered as promiscuous epitopes with supporting evidences of previously reported experimental results. Thus, we conclude that these regions should be considered as the important for design of specific therapeutic vaccines for cervical cancer.

  9. Effects of type II collagen epitope carbamylation and citrullination in human leucocyte antigen (HLA)-DR4(+) monozygotic twins discordant for rheumatoid arthritis.

    Science.gov (United States)

    De Santis, M; Ceribelli, A; Cavaciocchi, F; Generali, E; Massarotti, M; Isailovic, N; Crotti, C; Scherer, H U; Montecucco, C; Selmi, C

    2016-09-01

    The aim of this study is to investigate the effect of the native, citrullinated or carbamylated type II human collagen T cell- and B cell-epitopes on the adaptive immune response in rheumatoid arthritis (RA). Peripheral blood T and B cells obtained from a human leucocyte D4-related (antigen DR4(-) HLA-DR4)(+) woman with early RA, her healthy monozygotic twin and an unrelated HLA-DR3(+) woman with early RA were analysed for activation (CD154/CD69), apoptosis (annexin/7-aminoactinomycin), cytokine production [interferon (IFN)γ/interleukin (IL)-17/IL-4/IL-10/IL-6] and functional phenotype (CD45Ra/CCR7) after stimulation with the collagen native T cell epitope (T261-273), the K264 carbamylated T cell epitope (carT261-273), the native B cell epitope (B359-369) or the R360 citrullinated B cell epitope (citB359-369), and the combinations of these. The T cell memory compartment was activated by T cell epitopes in both discordant DR4(+) twins, but not in the DR3(+) RA. The collagen-specific activation of CD4(+) T cells was induced with both the native and carbamylated T cell epitopes only in the RA twin. Both T cell epitopes also induced IL-17 production in the RA twin, but a greater IL-4 and IL-10 response in the healthy twin. The citrullinated B cell epitope, particularly when combined with the carbamylated T cell epitope, induced B cell activation and an increased IL-6/IL-10 ratio in the RA twin compared to a greater IL-10 production in the healthy twin. Our data suggest that circulating collagen-specific T and B cells are found in HLA-DR4(+) subjects, but only RA activated cells express co-stimulatory molecules and produce proinflammatory cytokines. Carbamylation and citrullination further modulate the activation and cytokine polarization of T and B cells. PMID:27314557

  10. Gluten-specific antibodies of celiac disease gut plasma cells recognize long proteolytic fragments that typically harbor T-cell epitopes

    Science.gov (United States)

    Dørum, Siri; Steinsbø, Øyvind; Bergseng, Elin; Arntzen, Magnus Ø.; de Souza, Gustavo A.; Sollid, Ludvig M.

    2016-01-01

    This study aimed to identify proteolytic fragments of gluten proteins recognized by recombinant IgG1 monoclonal antibodies generated from single IgA plasma cells of celiac disease lesions. Peptides bound by monoclonal antibodies in complex gut-enzyme digests of gluten treated with the deamidating enzyme transglutaminase 2, were identified by mass spectrometry after antibody pull-down with protein G beads. The antibody bound peptides were long deamidated peptide fragments that contained the substrate recognition sequence of transglutaminase 2. Characteristically, the fragments contained epitopes with the sequence QPEQPFP and variants thereof in multiple copies, and they typically also harbored many different gluten T-cell epitopes. In the pull-down setting where antibodies were immobilized on a solid phase, peptide fragments with multivalent display of epitopes were targeted. This scenario resembles the situation of the B-cell receptor on the surface of B cells. Conceivably, B cells of celiac disease patients select gluten epitopes that are repeated multiple times in long peptide fragments generated by gut digestive enzymes. As the fragments also contain many different T-cell epitopes, this will lead to generation of strong antibody responses by effective presentation of several distinct T-cell epitopes and establishment of T-cell help to B cells. PMID:27146306

  11. T and B cell cooperation: a dance of life and death.

    Science.gov (United States)

    Bernard, Alain; Coitot, Sylvie; Brémont, Aurore; Bernard, Ghislaine

    2005-02-15

    In order for the body to develop a good antibody response, B cells need to react intimately with antigen specific T cells. Experimental evidence using hapten-carriers revealed that T and B cells do not recognize the same epitope and this led to the view that the physical contact is mediated by the antigen. Although the modern concept of antigen presentation has changed our perception on how the antigen can bridge both cells, the basic virtues of earlier bridging models remain. Over the past few years, a number of surface ligand-receptor pathways have been described, most of them belonging either to the CD28/B7 Ig or to the TNF/TNFR-like families. These act in concert, whether they are agonist or antagonist, in a timely and spatially organized manner. They form cascades of successive induction and recruitment to ensure that T-B cooperation is closely controlled at all stages of antibody induction. PMID:15699753

  12. Kvantitativ benchmark - Produktionsvirksomheder

    DEFF Research Database (Denmark)

    Sørensen, Ole H.; Andersen, Vibeke

    Rapport med resultatet af kvantitativ benchmark over produktionsvirksomhederne i VIPS projektet.......Rapport med resultatet af kvantitativ benchmark over produktionsvirksomhederne i VIPS projektet....

  13. The PRISM Benchmark Suite

    OpenAIRE

    Kwiatkowsa, Marta; Norman, Gethin; Parker, David

    2012-01-01

    We present the PRISM benchmark suite: a collection of probabilistic models and property specifications, designed to facilitate testing, benchmarking and comparisons of probabilistic verification tools and implementations.

  14. The Analysis of B-Cell Epitopes of Influenza Virus Hemagglutinin

    OpenAIRE

    Shcherbinin, D.N.; S. V Alekseeva; Shmarov, M.M.; Smirnov, Yu.A.; Naroditskiy, B.S.; Gintsburg, A.L.

    2016-01-01

    Vaccination has been successfully used to prevent influenza for a long time. Influenza virus hemagglutinin (HA), which induces a humoral immune response in humans and protection against the flu, is the main antigenic component of modern influenza vaccines. However, new seasonal and pandemic influenza virus variants with altered structures of HA occasionally occur. This allows the pathogen to avoid neutralization with antibodies produced in response to previous vaccination. Development of a va...

  15. THE ANALYSIS OF B-CELL EPITOPES OF INFLUENZA VIRUS HEMAGGLUTININ

    OpenAIRE

    Shcherbinin, D.N.; S. V Alekseeva; Shmarov, M.M.; SMIRNOV YU.A.; Naroditskiy, B.S.; Gintsburg, A.L.

    2016-01-01

    Vaccination has been successfully used to prevent influenza for a long time. Influenza virus hemagglutinin (HA), which induces a humoral immune response in humans and protection against the flu, is the main antigenic component of modern influenza vaccines. However, new seasonal and pandemic influenza virus variants with altered structures of HA occasionally occur. This allows the pathogen to avoid neutralization with antibodies produced in response to previous vaccination. Development of a va...

  16. Analysis of structures and epitopes of a novel secreted protein MYR1 in Toxoplasma gondii.

    Science.gov (United States)

    Zhou, Jian; Lu, Gang; He, Shenyi

    2016-01-01

    Toxoplasma gondii (Nicolle et Manceaux, 1908) is an obligate intracellular apicomplexan parasite and can infect warmblooded animals and humans all over the world. Development of effective vaccines is considered the only ideal way to control infection with T. gondii. However, only one live vaccine is commercially available for use in sheep and goats. Thus more effective antigenic proteins are searched for. In the present study we report a novel protein by secreted T. gondii termed Myc regulation 1 (MYR1). The physical and chemical characteristics, epitopes, hydrophilicity and functional sites of MYR1 were analysed by multiple bioinformatic approaches. The 3D models of MYR1 proteins were constructed and analysed. Furthermore, liner B-cell epitopes and T-cell epitopes of MYR1 protein and SAG1 were predicted. Compared to SAG1, MYR1 with good B-cell epitopes and T-cell epitopes had a potentiality to become a more successful vaccine against T. gondii. The bioinformatics analysis of MYR1 proteins could laid the foundation for further studies of its biological function experimentally and provide valuable information necessary for a better prevention and treatment of toxoplasmosis. PMID:27580381

  17. Proinflammatory GM-CSF-producing B cells in multiple sclerosis and B cell depletion therapy.

    Science.gov (United States)

    Li, Rui; Rezk, Ayman; Miyazaki, Yusei; Hilgenberg, Ellen; Touil, Hanane; Shen, Ping; Moore, Craig S; Michel, Laure; Althekair, Faisal; Rajasekharan, Sathy; Gommerman, Jennifer L; Prat, Alexandre; Fillatreau, Simon; Bar-Or, Amit

    2015-10-21

    B cells are not limited to producing protective antibodies; they also perform additional functions relevant to both health and disease. However, the relative contribution of functionally distinct B cell subsets in human disease, the signals that regulate the balance between such subsets, and which of these subsets underlie the benefits of B cell depletion therapy (BCDT) are only partially elucidated. We describe a proinflammatory, granulocyte macrophage-colony stimulating factor (GM-CSF)-expressing human memory B cell subset that is increased in frequency and more readily induced in multiple sclerosis (MS) patients compared to healthy controls. In vitro, GM-CSF-expressing B cells efficiently activated myeloid cells in a GM-CSF-dependent manner, and in vivo, BCDT resulted in a GM-CSF-dependent decrease in proinflammatory myeloid responses of MS patients. A signal transducer and activator of transcription 5 (STAT5)- and STAT6-dependent mechanism was required for B cell GM-CSF production and reciprocally regulated the generation of regulatory IL-10-expressing B cells. STAT5/6 signaling was enhanced in B cells of untreated MS patients compared with healthy controls, and B cells reemerging in patients after BCDT normalized their STAT5/6 signaling as well as their GM-CSF/IL-10 cytokine secretion ratios. The diminished proinflammatory myeloid cell responses observed after BCDT persisted even as new B cells reconstituted. These data implicate a proinflammatory B cell/myeloid cell axis in disease and underscore the rationale for selective targeting of distinct B cell populations in MS and other human autoimmune diseases. PMID:26491076

  18. Characterising B cell numbers and memory B cells in HIV infected and uninfected Malawian adults

    Directory of Open Access Journals (Sweden)

    Gordon Stephen

    2010-09-01

    Full Text Available Abstract Background Untreated human immunodeficiency virus (HIV disease disrupts B cell populations causing reduced memory and reduced naïve resting B cells leading to increases in specific co-infections and impaired responses to vaccines. To what extent antiretroviral treatment reverses these changes in an African population is uncertain. Methods A cross-sectional study was performed. We recruited HIV-uninfected and HIV-infected Malawian adults both on and off antiretroviral therapy attending the Queen Elizabeth Central hospital in Malawi. Using flow cytometry, we enumerated B cells and characterized memory B cells and compared these measurements by the different recruitment groups. Results Overall 64 participants were recruited - 20 HIV uninfected (HIV-, 30 HIV infected ART naïve (HIV+N and 14 HIV-infected ART treated (HIV+T. ART treatment had been taken for a median of 33 months (Range 12-60 months. Compared to HIV- the HIV+N adults had low absolute number of naïve resting B cells (111 vs. 180 cells/μl p = 0.008; reduced memory B cells (27 vs. 51 cells/μl p = 0.0008. The HIV+T adults had B-cell numbers similar to HIV- except for memory B cells that remained significantly lower (30 vs. 51 cells/μl p = 0.02. In the HIV+N group we did not find an association between CD4 count and B cell numbers. Conclusions HIV infected Malawian adults have abnormal B-cell numbers. Individuals treated with ART show a return to normal in B-cell numbers but a persistent deficit in the memory subset is noted. This has important implications for long term susceptibility to co-infections and should be evaluated further in a larger cohort study.

  19. Persistent Polyclonal B Cell Lymphocytosis B Cells Can Be Activated through CD40-CD154 Interaction

    Directory of Open Access Journals (Sweden)

    Emmanuelle Dugas-Bourdages

    2014-01-01

    Full Text Available Persistent polyclonal B cell lymphocytosis (PPBL is a rare disorder, diagnosed primarily in adult female smokers and characterized by an expansion of CD19+CD27+IgM+ memory B cells, by the presence of binucleated lymphocytes, and by a moderate elevation of serum IgM. The clinical course is usually benign, but it is not known whether or not PPBL might be part of a process leading to the emergence of a malignant proliferative disorder. In this study we sought to investigate the functional response of B cells from patients with PPBL by use of an optimal memory B cell culture model based on the CD40-CD154 interaction. We found that the proliferation of PPBL B cells was almost as important as that of B cells from normal controls, resulting in high immunoglobulin secretion with in vitro isotypic switching. We conclude that the CD40-CD154 activation pathway is functional in the memory B cell population of PPBL patients, suggesting that the disorder may be due to either a dysfunction of other cells in the microenvironment or a possible defect in another B cell activation pathway.

  20. Virus-like particles of chimeric recombinant porcine circovirus type 2 as antigen vehicle carrying foreign epitopes.

    Science.gov (United States)

    Zhang, Huawei; Qian, Ping; Liu, Lifeng; Qian, Suhong; Chen, Huanchun; Li, Xiangmin

    2014-12-01

    Virus-like particles (VLPs) of chimeric porcine circovirus type 2 (PCV2) were generated by replacing the nuclear localization signal (NLS; at 1-39 aa) of PCV2 capsid protein (Cap) with classical swine fever virus (CSFV) T-cell epitope (1446-1460 aa), CSFV B-cell epitope (693-716 aa) and CSFV T-cell epitope conjugated with B-cell epitope. The recombinant proteins were expressed using the baculovirus expression system and detected by immunoblotting and indirect immunofluorescence assay. The abilities to form PCV2 VLPs were confirmed by transmission electron microscopy. Immunogenicities of the three recombinant proteins were evaluated in mice. Our Results indicated that Cap protein NLS deletion or substitution with CSFV epitopes did not affect the VLPs assembly. Three chimeric Cap proteins could form VLPs and induce efficient humoral and cellular immunity against PCV2 and CSFV in mice. Results show that PCV2 VLPs can be used as an efficient antigen carrier for delivery of foreign epitopes, and a potential novel vaccine. PMID:25490764

  1. Virus-Like Particles of Chimeric Recombinant Porcine Circovirus Type 2 as Antigen Vehicle Carrying Foreign Epitopes

    Directory of Open Access Journals (Sweden)

    Huawei Zhang

    2014-12-01

    Full Text Available Virus-like particles (VLPs of chimeric porcine circovirus type 2 (PCV2 were generated by replacing the nuclear localization signal (NLS; at 1–39 aa of PCV2 capsid protein (Cap with classical swine fever virus (CSFV T-cell epitope (1446–1460 aa, CSFV B-cell epitope (693–716 aa and CSFV T-cell epitope conjugated with B-cell epitope. The recombinant proteins were expressed using the baculovirus expression system and detected by immunoblotting and indirect immunofluorescence assay. The abilities to form PCV2 VLPs were confirmed by transmission electron microscopy. Immunogenicities of the three recombinant proteins were evaluated in mice. Our Results indicated that Cap protein NLS deletion or substitution with CSFV epitopes did not affect the VLPs assembly. Three chimeric Cap proteins could form VLPs and induce efficient humoral and cellular immunity against PCV2 and CSFV in mice. Results show that PCV2 VLPs can be used as an efficient antigen carrier for delivery of foreign epitopes, and a potential novel vaccine.

  2. Early T Cell Recognition of B Cells following Epstein-Barr Virus Infection: Identifying Potential Targets for Prophylactic Vaccination.

    Directory of Open Access Journals (Sweden)

    Jill M Brooks

    2016-04-01

    Full Text Available Epstein-Barr virus, a B-lymphotropic herpesvirus, is the cause of infectious mononucleosis, has strong aetiologic links with several malignancies and has been implicated in certain autoimmune diseases. Efforts to develop a prophylactic vaccine to prevent or reduce EBV-associated disease have, to date, focused on the induction of neutralising antibody responses. However, such vaccines might be further improved by inducing T cell responses capable of recognising and killing recently-infected B cells. In that context, EBNA2, EBNA-LP and BHRF1 are the first viral antigens expressed during the initial stage of B cell growth transformation, yet have been poorly characterised as CD8+ T cell targets. Here we describe CD8+ T cell responses against each of these three "first wave" proteins, identifying target epitopes and HLA restricting alleles. While EBNA-LP and BHRF1 each contained one strong CD8 epitope, epitopes within EBNA2 induced immunodominant responses through several less common HLA class I alleles (e.g. B*3801 and B*5501, as well as subdominant responses through common class I alleles (e.g. B7 and C*0304. Importantly, such EBNA2-specific CD8+ T cells recognised B cells within the first day post-infection, prior to CD8+ T cells against well-characterised latent target antigens such as EBNA3B or LMP2, and effectively inhibited outgrowth of EBV-transformed B cell lines. We infer that "first wave" antigens of the growth-transforming infection, especially EBNA2, constitute potential CD8+ T cell immunogens for inclusion in prophylactic EBV vaccine design.

  3. Novel CD8(+) cytotoxic T cell epitopes in bovine leukemia virus with cattle.

    Science.gov (United States)

    Bai, Lanlan; Takeshima, Shin-Nosuke; Isogai, Emiko; Kohara, Junko; Aida, Yoko

    2015-12-16

    Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis and is closely related to human T cell leukemia virus (HTLV). The cytotoxic T lymphocyte (CTL) plays a key role in suppressing the progression of disease caused by BLV. T and B cell epitopes in BLV have been studied, but CD8(+) CTL epitopes remain poorly understood. We used a library of 115 synthetic peptides covering the entirety of the Env proteins (gp51 and gp30), the Gag proteins (p15, p24, and p12), and the Tax protein of BLV to identify 11 novel CD8(+) T cell epitopes (gp51N5, gp51N11, gp51N12, gp30N5, gp30N6, gp30N8, gp30N16, tax16, tax18, tax19, and tax20) in four calves experimentally infected with BLV. The number of CD8(+) T cell epitopes that could be identified in each calf correlated with the BLV proviral load. Interestingly, among the 11 epitopes identified, only gp51N11 was capable of inducing CD8(+) T cell-mediated cytotoxicity in all four calves, but it is not a suitable vaccine target because it shows a high degree of polymorphism according to the Wu-Kabat variability index. By contrast, no CTL epitopes were identified from the Gag structural protein. In addition, several epitopes were obtained from gp30 and Tax, indicating that cellular immunity against BLV is strongly targeted to these proteins. CD8(+) CTL epitopes from gp30 and Tax were less polymorphic than epitopes from. Indeed, peptides tax16, tax18, tax19, and tax20 include a leucine-rich activation domain that encompasses a transcriptional activation domain, and the gp30N16 peptide contains a proline-rich region that interacts with a protein tyrosine phosphatase SHP1 to regulate B cell activation. Moreover, at least one CD8(+) CTL epitope derived from gp30 was identified in each of the four calves. These results indicate that BLV gp30 may be the best candidate for the development of a BLV vaccine. PMID:26552001

  4. Novel CD8(+) cytotoxic T cell epitopes in bovine leukemia virus with cattle.

    Science.gov (United States)

    Bai, Lanlan; Takeshima, Shin-Nosuke; Isogai, Emiko; Kohara, Junko; Aida, Yoko

    2015-12-16

    Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis and is closely related to human T cell leukemia virus (HTLV). The cytotoxic T lymphocyte (CTL) plays a key role in suppressing the progression of disease caused by BLV. T and B cell epitopes in BLV have been studied, but CD8(+) CTL epitopes remain poorly understood. We used a library of 115 synthetic peptides covering the entirety of the Env proteins (gp51 and gp30), the Gag proteins (p15, p24, and p12), and the Tax protein of BLV to identify 11 novel CD8(+) T cell epitopes (gp51N5, gp51N11, gp51N12, gp30N5, gp30N6, gp30N8, gp30N16, tax16, tax18, tax19, and tax20) in four calves experimentally infected with BLV. The number of CD8(+) T cell epitopes that could be identified in each calf correlated with the BLV proviral load. Interestingly, among the 11 epitopes identified, only gp51N11 was capable of inducing CD8(+) T cell-mediated cytotoxicity in all four calves, but it is not a suitable vaccine target because it shows a high degree of polymorphism according to the Wu-Kabat variability index. By contrast, no CTL epitopes were identified from the Gag structural protein. In addition, several epitopes were obtained from gp30 and Tax, indicating that cellular immunity against BLV is strongly targeted to these proteins. CD8(+) CTL epitopes from gp30 and Tax were less polymorphic than epitopes from. Indeed, peptides tax16, tax18, tax19, and tax20 include a leucine-rich activation domain that encompasses a transcriptional activation domain, and the gp30N16 peptide contains a proline-rich region that interacts with a protein tyrosine phosphatase SHP1 to regulate B cell activation. Moreover, at least one CD8(+) CTL epitope derived from gp30 was identified in each of the four calves. These results indicate that BLV gp30 may be the best candidate for the development of a BLV vaccine.

  5. The Pre-B Cell Receptor and Its Function during B Cell Development

    Institute of Scientific and Technical Information of China (English)

    Min Zhang; Gopesh Srivastava1; Liwei Lu

    2004-01-01

    The process of B cell development in the bone marrow occurs by the stepwise rearrangements of the V, D, and Jsegments of the Ig H and L chain gene loci. During early B cell genesis, productive IgH chain generearrangement leads to assembly of the pre-B cell receptor (pre-BCR), which acts as an important checkpointat the pro-B/preB transitional stage. The pre-BCR, transiently expressed by developing precursor B cells,comprises the Ig μH chain, surrogate light (SL) chains VpreB and λ5, as well as the signal-transducing heterodimer Igα/Igβ. Signaling through the pre-BCR regulates allelic exclusion at the Ig H locus, stimulates cell proliferation, and induces differentiation to small post-mitotic pre-B cells that further undergo the rearrangement of the IgL chain genes. Recent advances in elucidating the key roles of pre-BCR in B cell development have provided a better understanding of normal B lymphopoiesis and its dysregulated state leading to B cell neoplasia.

  6. The Pre-B Cell Receptor and Its Function during B Cell Development

    Institute of Scientific and Technical Information of China (English)

    MinZhang; GopeshSrivastava; LiweiLu

    2004-01-01

    The process of B cell development in the bone marrow occurs by the stepwise rearrangements of the V, D, and J segments of the Ig H and L chain gene loci. During early B cell genesis, productive IgH chain gene rearrangement leads to assembly of the pre-B cell receptor (pre-BCR), which acts as an important checkpoint at the pro-B/preB transitional stage. The pre-BCR, transiently expressed by developing precursor B cells, comprises the Ig μH chain, surrogate light (SL) chains VpreB and λ5, as well as the signal-transducing hetero-dimer Igα/Igβ. Signaling through the pre-BCR regulates allelic exclusion at the Ig H locus, stimulates cell proliferation, and induces differentiation to small post-mitotic pre-B cells that further undergo the rearrangement of the IgL chain genes. Recent advances in elucidating the key roles of pre-BCR in B cell development have provided a better understanding of normal B lymphopoiesis and its dysregulated state leading to B cell neoplasia. Cellular & Molecular Immunology. 2004;1(2):89-94.

  7. T cell epitope-based allergy vaccines.

    Science.gov (United States)

    Larché, Mark

    2011-01-01

    Specific immunotherapy (SIT) with extracts containing intact allergen molecules is clinically efficacious, but associated with frequent adverse events related to the allergic sensitization of the patient. As a result, treatment is initiated in an incremental dose fashion which ultimately achieves a plateau (maintenance dose) that may be continued for several years. Reduction of allergic adverse events may allow safer and more rapid treatment Thus, many groups have developed and evaluated strategies to reduce allergenicity whilst maintaining immunogenicity, the latter being required to achieve specific modulation of the immune response. Peptide immunotherapy can be used to target T and/or B cells in an antigen-specific manner. To date, only approaches that target T cells have been clinically evaluated. Short, synthetic peptides representing immunodominant T cell epitopes of major allergens are able to modulate allergen-specific T cell responses in the absence of IgE cross linking and activation of effector cells. Here we review clinical and mechanistic studies associated with peptide immunotherapy targeting allergy to cats or to bee venom. 

  8. In silico cloning and B/T cell epitope prediction of triosephosphate isomerase from Echinococcus granulosus.

    Science.gov (United States)

    Wang, Fen; Ye, Bin

    2016-10-01

    Cystic echinococcosis is a worldwide zoonosis caused by Echinococcus granulosus. Because the methods of diagnosis and treatment for cystic echinococcosis were limited, it is still necessary to screen target proteins for the development of new anti-hydatidosis vaccine. In this study, the triosephosphate isomerase gene of E. granulosus was in silico cloned. The B cell and T cell epitopes were predicted by bioinformatics methods. The cDNA sequence of EgTIM was composition of 1094 base pairs, with an open reading frame of 753 base pairs. The deduced amino acid sequences were composed of 250 amino acids. Five cross-reactive epitopes, locating on 21aa-35aa, 43aa-57aa, 94aa-107aa, 115-129aa, and 164aa-183aa, could be expected to serve as candidate epitopes in the development of vaccine against E. granulosus. These results could provide bases for gene cloning, recombinant expression, and the designation of anti-hydatidosis vaccine.

  9. Aquatic Life Benchmarks

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Aquatic Life Benchmarks is an EPA-developed set of criteria for freshwater species. These benchmarks are based on toxicity values reviewed by EPA and used in...

  10. Prediction on Antigenic Epitope Characteristics of Bt Cry2Ab Protein in Transgenic Crops

    Institute of Scientific and Technical Information of China (English)

    Jierong GAO; Ying HE; Zehong ZOU; Ailin TAO; Yuncan AI

    2012-01-01

    Abstract [Objective] This study aimed to predict the structural characteristics of Bt Cry2Ab protein in transgenic crops with bioinformatic analysis to provide the theoreti- cal clues for design of antibody Cry2Ab. [Method] The amino acid sequence of Cry2Ab protein was searched from NCBI database. The B cell epitopes were pre- dicted with DNAStar. The binding affinity between Cry2Ab protein and MHC-II molecules was analyzed with NetMHCII 2.2 Server to predict the T cell epitopes. [Result] Prediction result suggested the potential B cell epitope of Cry2Ab locating in the region of 208-215. Analysis of the binding affinity between Cry2Ab and MHC-II molecules suggested the regions of 177-185, 299-307 and 255-263 were the po- tential T cell epitopes. Human with HLA-DRB10101 alleles and HLA-DRB10701 al- leles were more sensitive to Cry2Ab protein. [Conclusion] This study facilitates to un- derstand the structural characteristics of Cry2Ab protein and provides a new clue to improve the assessment method for potential allergenicity of genetically modified food.

  11. Conservation analysis of dengue virust-cell epitope-based vaccine candidates using peptide block entropy

    DEFF Research Database (Denmark)

    Olsen, Lars Rønn; Zhang, Guang Lan; Keskin, Derin B.;

    2011-01-01

    Broad coverage of the pathogen population is particularly important when designing CD8+ T-cell epitope vaccines against viral pathogens. Traditional approaches are based on combinations of highly conserved T-cell epitopes. Peptide block entropy analysis is a novel approach for assembling sets....... In contrast, the benchmark study by Khan et al. (2008) resulted in 165 conserved 9-mer peptides. Many of the conserved blocks are located consecutively in the proteins. Connecting these blocks resulted in 78 conserved regions. Of the 1551 blocks of 9-mer peptides 110 comprised predicted HLA binder sets...

  12. Impaired regulatory B cells in myasthenia gravis.

    Science.gov (United States)

    Sheng, Jian Rong; Rezania, Kourosh; Soliven, Betty

    2016-08-15

    Regulatory B cells (Bregs) attenuate the severity of experimental autoimmune myasthenia gravis (EAMG) in an interleukin-10 (IL-10)-dependent manner. The goal of this study was to investigate the role of human Bregs in MG focusing on CD19(+)CD1d(hi) CD5(+) and CD19(+)CD24(hi)CD38(hi) subsets. We found that MG patients exhibited a decrease in the frequency of both Breg subsets and IL-10 producing B cells within each subset, which correlated with disease severity. In addition, there was impaired suppression of Th1 polarization in MG. These findings, taken together with EAMG data, indicate that Bregs play an important role in regulating the severity of MG. PMID:27397074

  13. Primary Hepatosplenic Large B-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    M.R. Morales-Polanco

    2008-03-01

    Full Text Available Diffuse large B-cell lymphoma is the most common form of lymphoma. It usually begins in the lymph nodes; up to 40% may have an extranodal presentation. According to a definition of primary extranodal lymphoma with presentation only in extranodal sites, there are reports of large B-cell lymphomas limited to liver or spleen as separate entities, and to date there have been only three documented cases of primary hepatosplenic presentation. This paper reports a fourth case. Due to a review of the literature and the clinical course of the case reported, we conclude that primary hepatosplenic large B-cell lymphoma has been found predominantly in females older than 60 years. The patients reported had <2 months of evolution prior to diagnosis, prominent B symptoms, splenomegaly in three and hepatomegaly in two, none with lymph node involvement. All had thrombocytopenia and abnormal liver function tests; three had anemia and elevated serum lactic dehydrogenase levels, two with hemophagocytosis in bone marrow. Because of the previously mentioned data, it can be stated that primary hepatosplenic lymphoma is an uncommon and aggressive form of disease that requires immediate recognition and treatment.

  14. Prediction of Epitope-Based Peptides for the Utility of Vaccine Development from Fusion and Glycoprotein of Nipah Virus Using In Silico Approach

    Directory of Open Access Journals (Sweden)

    M. Sadman Sakib

    2014-01-01

    Full Text Available This study aims to design epitope-based peptides for the utility of vaccine development by targeting glycoprotein G and envelope protein F of Nipah virus (NiV that, respectively, facilitate attachment and fusion of NiV with host cells. Using various databases and tools, immune parameters of conserved sequence(s from G and F proteins of different isolates of NiV were tested to predict probable epitope(s. Binding analyses of the peptides with MHC class-I and class-II molecules, epitope conservancy, population coverage, and linear B cell epitope prediction were analyzed. Predicted peptides interacted with seven or more MHC alleles and illustrated population coverage of more than 99% and 95%, for G and F proteins, respectively. The predicted class-I nonamers, SLIDTSSTI and EWISIVPNF, superimposed on the putative decameric B cell epitopes, were also identified as core sequences of the most probable class-II 15-mer peptides GPKVSLIDTSSTITI and EWISIVPNFILVRNT. These peptides were further validated for their binding to specific HLA alleles using in silico docking technique. Our in silico analysis suggested that the predicted epitopes, either GPKVSLIDTSSTITI or EWISIVPNFILVRNT, could be a better choice as universal vaccine component against NiV irrespective of different isolates which may elicit both humoral and cell-mediated immunity.

  15. Benchmarking semantic web technology

    CERN Document Server

    García-Castro, R

    2009-01-01

    This book addresses the problem of benchmarking Semantic Web Technologies; first, from a methodological point of view, proposing a general methodology to follow in benchmarking activities over Semantic Web Technologies and, second, from a practical point of view, presenting two international benchmarking activities that involved benchmarking the interoperability of Semantic Web technologies using RDF(S) as the interchange language in one activity and OWL in the other.The book presents in detail how the different resources needed for these interoperability benchmarking activities were defined:

  16. Designing an efficient multi-epitope peptide vaccine against Vibrio cholerae via combined immunoinformatics and protein interaction based approaches.

    Science.gov (United States)

    Nezafat, Navid; Karimi, Zeinab; Eslami, Mahboobeh; Mohkam, Milad; Zandian, Sanam; Ghasemi, Younes

    2016-06-01

    Cholera continues to be a major global health concern. Among different Vibrio cholerae strains, only O1 and O139 cause acute diarrheal diseases that are related to epidemic and pandemic outbreaks. The currently available cholera vaccines are mainly lived and attenuated vaccines consisting of V. cholerae virulence factors such as toxin-coregulated pili (TCP), outer membrane proteins (Omps), and nontoxic cholera toxin B subunit (CTB). Nowadays, there is a great interest in designing an efficient epitope vaccine against cholera. Epitope vaccines consisting of immunodominant epitopes and adjuvant molecules enhance the possibility of inciting potent protective immunity. In this study, V. cholerae protective antigens (OmpW, OmpU, TcpA and TcpF) and the CTB, which is broadly used as an immunostimulatory adjuvant, were analyzed using different bioinformatics and immunoinformatics tools. The common regions between promiscuous epitopes, binding to various HLA-II supertype alleles, and B-cell epitopes were defined based upon the aforementioned protective antigens. The ultimately selected epitopes and CTB adjuvant were fused together using proper GPGPG linkers to enhance vaccine immunogenicity. A three-dimensional model of the thus constructed vaccine was generated using I-TASSER. The model was structurally validated using the ProSA-web error-detection software and the Ramachandran plot. The validation results indicated that the initial 3D model needed refinement. Subsequently, a high-quality model obtained after various refinement cycles was used for defining conformational B-cell epitopes. Several linear and conformational B-cell epitopes were determined within the epitope vaccine, suggesting likely antibody triggering features of our designed vaccine. Next, molecular docking was performed between the 3D vaccine model and the tertiary structure of the toll like receptor 2 (TLR2). To gain further insight into the interaction between vaccine and TLR2, molecular dynamics

  17. A novel antibody discovery platform identifies anti-influenza A broadly neutralizing antibodies from human memory B cells.

    Science.gov (United States)

    Xiao, Xiaodong; Chen, Yan; Varkey, Reena; Kallewaard, Nicole; Koksal, Adem C; Zhu, Qing; Wu, Herren; Chowdhury, Partha S; Dall'Acqua, William F

    2016-07-01

    Monoclonal antibody isolation directly from circulating human B cells is a powerful tool to delineate humoral responses to pathological conditions and discover antibody therapeutics. We have developed a platform aimed at improving the efficiencies of B cell selection and V gene recovery. Here, memory B cells are activated and amplified using Epstein-Barr virus infection, co-cultured with CHO-muCD40L cells, and then assessed by functional screenings. An in vitro transcription and translation (IVTT) approach was used to analyze variable (V) genes recovered from each B cell sample and identify the relevant heavy/light chain pair(s). We achieved efficient amplification and activation of memory B cells, and eliminated the need to: 1) seed B cells at clonal level (≤1 cell/well) or perform limited dilution cloning; 2) immortalize B cells; or 3) assemble V genes into an IgG expression vector to confirm the relevant heavy/light chain pairing. Cross-reactive antibodies targeting a conserved epitope on influenza A hemagglutinin were successfully isolated from a healthy donor. In-depth analysis of the isolated antibodies suggested their potential uses as anti-influenza A antibody therapeutics and uncovered a distinct affinity maturation pathway. Importantly, our results showed that cognate heavy/light chain pairings contributed to both the expression level and binding abilities of our newly isolated VH1-69 family, influenza A neutralizing antibodies, contrasting with previous observations that light chains do not significantly contribute to the function of this group of antibodies. Our results further suggest the potential use of the IVTT as a powerful antibody developability assessment tool. PMID:27049174

  18. Benchmarking in University Toolbox

    Directory of Open Access Journals (Sweden)

    Katarzyna Kuźmicz

    2015-06-01

    Full Text Available In the face of global competition and rising challenges that higher education institutions (HEIs meet, it is imperative to increase innovativeness and efficiency of their management. Benchmarking can be the appropriate tool to search for a point of reference necessary to assess institution’s competitive position and learn from the best in order to improve. The primary purpose of the paper is to present in-depth analysis of benchmarking application in HEIs worldwide. The study involves indicating premises of using benchmarking in HEIs. It also contains detailed examination of types, approaches and scope of benchmarking initiatives. The thorough insight of benchmarking applications enabled developing classification of benchmarking undertakings in HEIs. The paper includes review of the most recent benchmarking projects and relating them to the classification according to the elaborated criteria (geographical range, scope, type of data, subject, support and continuity. The presented examples were chosen in order to exemplify different approaches to benchmarking in higher education setting. The study was performed on the basis of the published reports from benchmarking projects, scientific literature and the experience of the author from the active participation in benchmarking projects. The paper concludes with recommendations for university managers undertaking benchmarking, derived on the basis of the conducted analysis.

  19. Immune recognition of citrullinated epitopes.

    Science.gov (United States)

    Nguyen, Hai; James, Eddie A

    2016-10-01

    Conversion of arginine into citrulline is a post-translational modification that is observed in normal physiological processes. However, abnormal citrullination can provoke autoimmunity by generating altered self-epitopes that are specifically targeted by autoantibodies and T cells. In this review we discuss the recognition of citrullinated antigens in human autoimmune diseases and the role that this modification plays in increasing antigenic diversity and circumventing tolerance mechanisms. Early published work demonstrated that citrullinated proteins are specifically targeted by autoantibodies in rheumatoid arthritis and that citrullinated peptides are more readily presented to T cells by arthritis-susceptible HLA class II 'shared epitope' proteins. Emerging data support the relevance of citrullinated epitopes in other autoimmune diseases, including type 1 diabetes and multiple sclerosis, whose susceptible HLA haplotypes also preferentially present citrullinated peptides. In these settings, autoimmune patients have been shown to have elevated responses to citrullinated epitopes derived from tissue-specific antigens. Contrasting evidence implicates autophagy or perforin and complement-mediated membrane attack as inducers of ectopic citrullination. In either case, the peptidyl deiminases responsible for citrullination are activated in response to inflammation or insult, providing a mechanistic link between this post-translational modification and interactions with the environment and infection. As such, it is likely that immune recognition of citrullinated epitopes also plays a role in pathogen clearance. Indeed, our recent data suggest that responses to citrullinated peptides facilitate recognition of novel influenza strains. Therefore, increased understanding of responses to citrullinated epitopes may provide important insights about the initiation of autoimmunity and recognition of heterologous viruses. PMID:27531825

  20. A B-Cell Superantigen Induces the Apoptosis of Murine and Human Malignant B Cells

    Science.gov (United States)

    Lorenzo, Daniela; Duarte, Alejandra; Mundiñano, Juliana; Berguer, Paula; Nepomnaschy, Irene; Piazzon, Isabel

    2016-01-01

    B-cell superantigens (Sags) bind to conserved sites of the VH or VL regions of immunoglobulin molecules outside their complementarity-determining regions causing the apoptosis of normal cognate B cells. No attempts to investigate whether B-cell Sags are able to induce the apoptosis of cognate malignant B cells were reported. In the present study we show that protein L (PpL), secreted by Finegoldia magna, a B-cell Sag which interacts with κ+ bearing cells, induces the apoptosis of murine and human κ+ lymphoma B cells both in vitro and in vivo. Apoptosis was not altered by caspase-8 inhibitor. No alterations in the levels of Bid, Fas and Fas-L were found suggesting that PpL does not activate the extrinsic pathway of apoptosis. The involvement of the intrinsic pathway was clearly indicated by: i) alterations in mitochondrial membrane potential (ΔΨm) both in murine and human lymphoma cells exposed to PpL; ii) decreased levels of apoptosis in the presence of caspase-9 inhibitor; iii) significant increases of Bim and Bax protein levels and downregulation of Bcl-2; iv) the translocation from the cytoplasm to the mitochondria of Bax and Bim pro-apoptotic proteins and its inhibition by caspase-9 inhibitor but not by caspase-8 inhibitor and v) the translocation of Bcl-2 protein from the mitochondria to the cytosol and its inhibition by caspase-9 inhibitor but not by caspase-8 inhibitor. The possibility of a therapeutic use of Sags in lymphoma/leukemia B cell malignancies is discussed. PMID:27603942

  1. A B-Cell Superantigen Induces the Apoptosis of Murine and Human Malignant B Cells.

    Science.gov (United States)

    Lorenzo, Daniela; Duarte, Alejandra; Mundiñano, Juliana; Berguer, Paula; Nepomnaschy, Irene; Piazzon, Isabel

    2016-01-01

    B-cell superantigens (Sags) bind to conserved sites of the VH or VL regions of immunoglobulin molecules outside their complementarity-determining regions causing the apoptosis of normal cognate B cells. No attempts to investigate whether B-cell Sags are able to induce the apoptosis of cognate malignant B cells were reported. In the present study we show that protein L (PpL), secreted by Finegoldia magna, a B-cell Sag which interacts with κ+ bearing cells, induces the apoptosis of murine and human κ+ lymphoma B cells both in vitro and in vivo. Apoptosis was not altered by caspase-8 inhibitor. No alterations in the levels of Bid, Fas and Fas-L were found suggesting that PpL does not activate the extrinsic pathway of apoptosis. The involvement of the intrinsic pathway was clearly indicated by: i) alterations in mitochondrial membrane potential (ΔΨm) both in murine and human lymphoma cells exposed to PpL; ii) decreased levels of apoptosis in the presence of caspase-9 inhibitor; iii) significant increases of Bim and Bax protein levels and downregulation of Bcl-2; iv) the translocation from the cytoplasm to the mitochondria of Bax and Bim pro-apoptotic proteins and its inhibition by caspase-9 inhibitor but not by caspase-8 inhibitor and v) the translocation of Bcl-2 protein from the mitochondria to the cytosol and its inhibition by caspase-9 inhibitor but not by caspase-8 inhibitor. The possibility of a therapeutic use of Sags in lymphoma/leukemia B cell malignancies is discussed. PMID:27603942

  2. Multi-epitope Models Explain How Pre-existing Antibodies Affect the Generation of Broadly Protective Responses to Influenza

    Science.gov (United States)

    Zarnitsyna, Veronika I.; Lavine, Jennie; Ellebedy, Ali; Ahmed, Rafi; Antia, Rustom

    2016-01-01

    The development of next-generation influenza vaccines that elicit strain-transcendent immunity against both seasonal and pandemic viruses is a key public health goal. Targeting the evolutionarily conserved epitopes on the stem of influenza’s major surface molecule, hemagglutinin, is an appealing prospect, and novel vaccine formulations show promising results in animal model systems. However, studies in humans indicate that natural infection and vaccination result in limited boosting of antibodies to the stem of HA, and the level of stem-specific antibody elicited is insufficient to provide broad strain-transcendent immunity. Here, we use mathematical models of the humoral immune response to explore how pre-existing immunity affects the ability of vaccines to boost antibodies to the head and stem of HA in humans, and, in particular, how it leads to the apparent lack of boosting of broadly cross-reactive antibodies to the stem epitopes. We consider hypotheses where binding of antibody to an epitope: (i) results in more rapid clearance of the antigen; (ii) leads to the formation of antigen-antibody complexes which inhibit B cell activation through Fcγ receptor-mediated mechanism; and (iii) masks the epitope and prevents the stimulation and proliferation of specific B cells. We find that only epitope masking but not the former two mechanisms to be key in recapitulating patterns in data. We discuss the ramifications of our findings for the development of vaccines against both seasonal and pandemic influenza. PMID:27336297

  3. Gastrointestinal B-cell lymphomas: From understanding B-cell physiology to classification and molecular pathology.

    Science.gov (United States)

    Sagaert, Xavier; Tousseyn, Thomas; Yantiss, Rhonda K

    2012-12-15

    The gut is the most common extranodal site where lymphomas arise. Although all histological lymphoma types may develop in the gut, small and large B-cell lymphomas predominate. The sometimes unexpected finding of a lymphoid lesion in an endoscopic biopsy of the gut may challenge both the clinician (who is not always familiar with lymphoma pathogenesis) and the pathologist (who will often be hampered in his/her diagnostic skill by the limited amount of available tissue). Moreover, the past 2 decades have spawned an avalanche of new data that encompasses both the function of the reactive B-cell as well as the pathogenic pathways that lead to its neoplastic counterpart, the B-cell lymphoma. Therefore, this review aims to offer clinicians an overview of B-cell lymphomas in the gut, and their pertinent molecular features that have led to new insights regarding lymphomagenesis. It addresses the question as how to incorporate all presently available information on normal and neoplastic B-cell differentiation, and how this knowledge can be applied in daily clinical practice (e.g., diagnostic tools, prognostic biomarkers or therapeutic targets) to optimalise the managment of this heterogeneous group of neoplasms. PMID:23443141

  4. The nature and combination of subunits used in epitope-based Schistosoma japonicum vaccine formulations affect their efficacy

    Directory of Open Access Journals (Sweden)

    Liu Feng

    2010-11-01

    Full Text Available Abstract Background Schistosomiasis remains a major public health problem in endemic countries and is caused by infections with any one of three primary schistosome species. Although there are no vaccines available to date, this strategy appears feasible since natural immunity develops in individuals suffering from repeated infection during a lifetime. Since vaccinations resulting in both Th1- and Th2-type responses have been shown to contribute to protective immunity, a vaccine formulation with the capacity for stimulating multiple arms of the immune response will likely be the most effective. Previously we developed partially protective, single Th- and B cell-epitope-based peptide-DNA dual vaccines (PDDV (T3-PDDV and B3-PDDV, respectively capable of eliciting immune responses against the Schistosoma japonicum 22.6 kDa tegument antigen (Sj22.6 and a 62 kDa fragment of myosin (Sj62, respectively. Results In this study, we developed PDDV cocktails containing multiple epitopes of S. japonicum from Sj22.6, Sj62 and Sj97 antigens by predicting cytotoxic, helper, and B-cell epitopes, and evaluated vaccine potential in vivo. Results showed that mice immunized with a single-epitope PDDV elicited either Tc, Th, or B cell responses, respectively, and mice immunized with either the T3- or B3- single-epitope PDDV formulation were partially protected against infection. However, mice immunized with a multicomponent (3 PDDV components formulation elicited variable immune responses that were less immunoprotective than single-epitope PDDV formulations. Conclusions Our data show that combining these different antigens did not result in a more effective vaccine formulation when compared to each component administered individually, and further suggest that immune interference resulting from immunizations with antigenically distinct vaccine targets may be an important consideration in the development of multicomponent vaccine preparations.

  5. Analysis of memory B cell responses and isolation of novel monoclonal antibodies with neutralizing breadth from HIV-1-infected individuals.

    Directory of Open Access Journals (Sweden)

    Davide Corti

    Full Text Available BACKGROUND: The isolation of human monoclonal antibodies (mAbs that neutralize a broad spectrum of primary HIV-1 isolates and the characterization of the human neutralizing antibody B cell response to HIV-1 infection are important goals that are central to the design of an effective antibody-based vaccine. METHODS AND FINDINGS: We immortalized IgG(+ memory B cells from individuals infected with diverse clades of HIV-1 and selected on the basis of plasma neutralization profiles that were cross-clade and relatively potent. Culture supernatants were screened using various recombinant forms of the envelope glycoproteins (Env in multiple parallel assays. We isolated 58 mAbs that were mapped to different Env surfaces, most of which showed neutralizing activity. One mAb in particular (HJ16 specific for a novel epitope proximal to the CD4 binding site on gp120 selectively neutralized a multi-clade panel of Tier-2 HIV-1 pseudoviruses, and demonstrated reactivity that was comparable in breadth, but distinct in neutralization specificity, to that of the other CD4 binding site-specific neutralizing mAb b12. A second mAb (HGN194 bound a conserved epitope in the V3 crown and neutralized all Tier-1 and a proportion of Tier-2 pseudoviruses tested, irrespective of clade. A third mAb (HK20 with broad neutralizing activity, particularly as a Fab fragment, recognized a highly conserved epitope in the HR-1 region of gp41, but showed striking assay-dependent selectivity in its activity. CONCLUSIONS: This study reveals that by using appropriate screening methods, a large proportion of memory B cells can be isolated that produce mAbs with HIV-1 neutralizing activity. Three of these mAbs show unusual breadth of neutralization and therefore add to the current panel of HIV-1 neutralizing antibodies with potential for passive protection and template-based vaccine design.

  6. B-Cell Response during Protozoan Parasite Infections

    OpenAIRE

    Amezcua Vesely, María C; Bermejo, Daniela A.; Montes, Carolina L.; Acosta-Rodríguez, Eva V.; Adriana Gruppi

    2012-01-01

    In this review, we discuss how protozoan parasites alter immature and mature B cell compartment. B1 and marginal zone (MZ) B cells, considered innate like B cells, are activated during protozoan parasite infections, and they generate short lived plasma cells providing a prompt antibody source. In addition, protozoan infections induce massive B cell response with polyclonal activation that leads to hypergammaglobulnemia with serum antibodies specific for the parasites and self and/or non relat...

  7. Activation-Induced Cytidine Deaminase Expression in Human B Cell Precursors Is Essential for Central B Cell Tolerance.

    Science.gov (United States)

    Cantaert, Tineke; Schickel, Jean-Nicolas; Bannock, Jason M; Ng, Yen-Shing; Massad, Christopher; Oe, Tyler; Wu, Renee; Lavoie, Aubert; Walter, Jolan E; Notarangelo, Luigi D; Al-Herz, Waleed; Kilic, Sara Sebnem; Ochs, Hans D; Nonoyama, Shigeaki; Durandy, Anne; Meffre, Eric

    2015-11-17

    Activation-induced cytidine deaminase (AID), the enzyme-mediating class-switch recombination (CSR) and somatic hypermutation (SHM) of immunoglobulin genes, is essential for the removal of developing autoreactive B cells. How AID mediates central B cell tolerance remains unknown. We report that AID enzymes were produced in a discrete population of immature B cells that expressed recombination-activating gene 2 (RAG2), suggesting that they undergo secondary recombination to edit autoreactive antibodies. However, most AID+ immature B cells lacked anti-apoptotic MCL-1 and were deleted by apoptosis. AID inhibition using lentiviral-encoded short hairpin (sh)RNA in B cells developing in humanized mice resulted in a failure to remove autoreactive clones. Hence, B cell intrinsic AID expression mediates central B cell tolerance potentially through its RAG-coupled genotoxic activity in self-reactive immature B cells.

  8. The Conic Benchmark Format

    DEFF Research Database (Denmark)

    Friberg, Henrik A.

    This document constitutes the technical reference manual of the Conic Benchmark Format with le extension: .cbf or .CBF. It unies linear, second-order cone (also known as conic quadratic) and semidenite optimization with mixed-integer variables. The format has been designed with benchmark libraries...... in mind, and therefore focuses on compact and easily parsable representations. The problem structure is separated from the problem data, and the format moreover facilitate benchmarking of hotstart capability through sequences of changes....

  9. Aeroelastic Benchmark Experiments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — M4 Engineering proposes to conduct canonical aeroelastic benchmark experiments. These experiments will augment existing sources for aeroelastic data in the...

  10. Generation of stable monoclonal antibody-producing B cell receptor-positive human memory B cells by genetic programming

    NARCIS (Netherlands)

    Kwakkenbos, Mark J.; Diehl, Sean A.; Yasuda, Etsuko; Bakker, Arjen Q.; van Geelen, Caroline M. M.; Lukens, Michaël; van Bleek, Grada M.; Widjojoatmodjo, Myra N.; Bogers, Willy M. J. M.; Mei, Henrik; Radbruch, Andreas; Scheeren, Ferenc A.; Spits, Hergen; Beaumont, Tim

    2010-01-01

    The B cell lymphoma-6 (Bcl-6) and Bcl-xL proteins are expressed in germinal center B cells and enable them to endure the proliferative and mutagenic environment of the germinal center. By introducing these genes into peripheral blood memory B cells and culturing these cells with two factors produced

  11. Dengue Virus Directly Stimulates Polyclonal B Cell Activation

    Science.gov (United States)

    Papa, Michelle Premazzi; de Morais, Ana Theresa Silveira; Peçanha, Ligia Maria Torres; de Arruda, Luciana Barros

    2015-01-01

    Dengue infection is associated to vigorous inflammatory response, to a high frequency of activated B cells, and to increased levels of circulating cross-reactive antibodies. We investigated whether direct infection of B cells would promote activation by culturing primary human B lymphocytes from healthy donors with DENV in vitro. B cells were susceptible, but poorly permissive to infection. Even though, primary B cells cultured with DENV induced substantial IgM secretion, which is a hallmark of polyclonal B cell activation. Notably, DENV induced the activation of B cells obtained from either DENV immune or DENV naïve donors, suggesting that it was not dependent on DENV-specific secondary/memory response. B cell stimulation was dependent on activation of MAPK and CD81. B cells cultured with DENV also secreted IL-6 and presented increased expression of CD86 and HLA-DR, which might contribute to B lymphocyte co-stimulatory function. Indeed, PBMCs, but not isolated B cells, secreted high amounts of IgG upon DENV culture, suggesting that interaction with other cell types in vivo might promote Ig isotype switching and IgG secretion from different B cell clones. These findings suggest that activation signaling pathways triggered by DENV interaction with non-specific receptors on B cells might contribute to the exacerbated response observed in dengue patients. PMID:26656738

  12. A new EV71 VP3 epitope in norovirus P particle vector displays neutralizing activity and protection in vivo in mice.

    Science.gov (United States)

    Jiang, Liping; Fan, Rongjun; Sun, Shiyang; Fan, Peihu; Su, Weiheng; Zhou, Yan; Gao, Feng; Xu, Fei; Kong, Wei; Jiang, Chunlai

    2015-11-27

    Enterovirus 71 (EV71) and Coxsackievirus A16 (CVA16), as the main agents causing hand, foot and mouth disease (HFMD), have become a serious public health concern in the Asia-Pacific region. Recently, various neutralizing B cell epitopes of EV71 were identified as targets for promising vaccine candidates. Structural studies of Picornaviridae indicated that potent immunodominant epitopes typically lie in the hypervariable loop of capsid surfaces. However, cross-neutralizing antibodies and cross-protection between EV71 and CVA16 have not been observed. Therefore, we speculated that divergent sequences of the two viruses are key epitopes for inducing protective neutralizing responses. In this study, we selected 10 divergent epitope candidates based on alignment of the EV71 and CVA16 P1 amino acid sequences using the Multalin interface page, and these epitopes are conserved among all subgenotypes of EV71. Simultaneously, by utilizing the norovirus P particle as a novel vaccine delivery carrier, we identified the 71-6 epitope (amino acid 176-190 of VP3) as a conformational neutralizing epitope against EV71 in an in vitro micro-neutralization assay as well as an in vivo protection assay in mice. Altogether, these results indicated that the incorporation of the 71-6 epitope into the norovirus P domain can provide a promising candidate for an effective synthetic peptide-based vaccine against EV71.

  13. A new EV71 VP3 epitope in norovirus P particle vector displays neutralizing activity and protection in vivo in mice.

    Science.gov (United States)

    Jiang, Liping; Fan, Rongjun; Sun, Shiyang; Fan, Peihu; Su, Weiheng; Zhou, Yan; Gao, Feng; Xu, Fei; Kong, Wei; Jiang, Chunlai

    2015-11-27

    Enterovirus 71 (EV71) and Coxsackievirus A16 (CVA16), as the main agents causing hand, foot and mouth disease (HFMD), have become a serious public health concern in the Asia-Pacific region. Recently, various neutralizing B cell epitopes of EV71 were identified as targets for promising vaccine candidates. Structural studies of Picornaviridae indicated that potent immunodominant epitopes typically lie in the hypervariable loop of capsid surfaces. However, cross-neutralizing antibodies and cross-protection between EV71 and CVA16 have not been observed. Therefore, we speculated that divergent sequences of the two viruses are key epitopes for inducing protective neutralizing responses. In this study, we selected 10 divergent epitope candidates based on alignment of the EV71 and CVA16 P1 amino acid sequences using the Multalin interface page, and these epitopes are conserved among all subgenotypes of EV71. Simultaneously, by utilizing the norovirus P particle as a novel vaccine delivery carrier, we identified the 71-6 epitope (amino acid 176-190 of VP3) as a conformational neutralizing epitope against EV71 in an in vitro micro-neutralization assay as well as an in vivo protection assay in mice. Altogether, these results indicated that the incorporation of the 71-6 epitope into the norovirus P domain can provide a promising candidate for an effective synthetic peptide-based vaccine against EV71. PMID:26529072

  14. Regulation of normal B-cell differentiation and malignant B-cell survival by OCT2.

    Science.gov (United States)

    Hodson, Daniel J; Shaffer, Arthur L; Xiao, Wenming; Wright, George W; Schmitz, Roland; Phelan, James D; Yang, Yandan; Webster, Daniel E; Rui, Lixin; Kohlhammer, Holger; Nakagawa, Masao; Waldmann, Thomas A; Staudt, Louis M

    2016-04-01

    The requirement for the B-cell transcription factor OCT2 (octamer-binding protein 2, encoded by Pou2f2) in germinal center B cells has proved controversial. Here, we report that germinal center B cells are formed normally after depletion of OCT2 in a conditional knockout mouse, but their proliferation is reduced and in vivo differentiation to antibody-secreting plasma cells is blocked. This finding led us to examine the role of OCT2 in germinal center-derived lymphomas. shRNA knockdown showed that almost all diffuse large B-cell lymphoma (DLBCL) cell lines are addicted to the expression of OCT2 and its coactivator OCA-B. Genome-wide chromatin immunoprecipitation (ChIP) analysis and gene-expression profiling revealed the broad transcriptional program regulated by OCT2 that includes the expression of STAT3, IL-10, ELL2, XBP1, MYC, TERT, and ADA. Importantly, genetic alteration of OCT2 is not a requirement for cellular addiction in DLBCL. However, we detected amplifications of the POU2F2 locus in DLBCL tumor biopsies and a recurrent mutation of threonine 223 in the DNA-binding domain of OCT2. This neomorphic mutation subtly alters the DNA-binding preference of OCT2, leading to the transactivation of noncanonical target genes including HIF1a and FCRL3 Finally, by introducing mutations designed to disrupt the OCT2-OCA-B interface, we reveal a requirement for this protein-protein interface that ultimately might be exploited therapeutically. Our findings, combined with the predominantly B-cell-restricted expression of OCT2 and the absence of a systemic phenotype in our knockout mice, suggest that an OCT2-targeted therapeutic strategy would be efficacious in both major subtypes of DLBCL while avoiding systemic toxicity. PMID:26993806

  15. Immune history profoundly affects broadly protective B cell responses to influenza

    Science.gov (United States)

    Andrews, Sarah F.; Huang, Yunping; Kaur, Kaval; Popova, Lyubov I.; Ho, Irvin Y.; Pauli, Noel T.; Dunand, Carole J. Henry; Taylor, William M; Lim, Samuel; Huang, Min; Qu, Xinyan; Lee, Jane-Hwei; Salgado-Ferrer, Marlene; Krammer, Florian; Palese, Peter; Wrammert, Jens; Ahmed, Rafi; Wilson, Patrick C.

    2016-01-01

    Generating a broadly protective influenza vaccine is critical to global health. Understanding how immune memory influences influenza immunity is central to this goal. We undertook an in-depth study of the B cell response to the pandemic 2009 H1N1 vaccine over consecutive years. Analysis of monoclonal Abs generated from vaccine-induced plasmablasts demonstrated that individuals with low preexisting serological titers to the vaccinating strain generated a broadly reactive, HA stalk-biased, response. Higher preexisting serum antibody levels correlated with a strain-specific HA head-dominated response. We demonstrate that this HA head immunodominance encompasses poor accessibility of the HA stalk epitopes. Further, we show polyreactivity of HA stalk-reactive antibodies that could cause counterselection of these cells. Thus, preexisting memory against HA head epitopes predominate, inhibiting a broadly protective response against the HA stalk upon revaccination with similar strains. Consideration of influenza exposure history is critical for new vaccine strategies designed to elicit broadly neutralizing antibodies. PMID:26631631

  16. The human intestinal B-cell response.

    Science.gov (United States)

    Spencer, J; Sollid, L M

    2016-09-01

    The intestinal immune system is chronically challenged by a huge plethora of antigens derived from the lumen. B-cell responses in organized gut-associated lymphoid tissues and regional lymph nodes that are driven chronically by gut antigens generate the largest population of antibody-producing cells in the body: the gut lamina propria plasma cells. Although animal studies have provided insights into mechanisms that underpin this dynamic process, some very fundamental differences in this system appear to exist between species. Importantly, this prevents extrapolation from mice to humans to inform translational research questions. Therefore, in this review we will describe the structures and mechanisms involved in the propagation, dissemination, and regulation of this immense plasma cell population in man. Uniquely, we will seek our evidence exclusively from studies of human cells and tissues. PMID:27461177

  17. Rheumatoid factors, B cells and immunoglobulin genes.

    Science.gov (United States)

    Jefferis, R

    1995-04-01

    The paradigm of self, non-self discrimination in the immune system is under review as autoreactive B or T cells are increasingly delineated within normal individuals. The products of autoreactive B cells are, mostly, polyspecific IgM antibodies of low affinity. These 'natural' antibodies include rheumatoid factors (RF) encoded by unmutated germline immunoglobulin genes. In rheumatoid arthritis (RA) the RF may be of the IgM, IgG or IgA isotype, show evidence of somatic mutation and have increased affinity; consistent with maturation of an antigen driven immune response. This response could be initiated or driven by an auto-immunogenic form of IgG or an exogenous cross-reactive antigen. Changes in galactosylation of IgG have been reported to be a valuable diagnostic and prognostic indicator in RA. Speculation that these changes may precipitate some of the disease processes is critically reviewed.

  18. The Transcription Factor Bach2 Is Phosphorylated at Multiple Sites in Murine B Cells but a Single Site Prevents Its Nuclear Localization.

    Science.gov (United States)

    Ando, Ryo; Shima, Hiroki; Tamahara, Toru; Sato, Yoshihiro; Watanabe-Matsui, Miki; Kato, Hiroki; Sax, Nicolas; Motohashi, Hozumi; Taguchi, Keiko; Yamamoto, Masayuki; Nio, Masaki; Maeda, Tatsuya; Ochiai, Kyoko; Muto, Akihiko; Igarashi, Kazuhiko

    2016-01-22

    The transcription factor Bach2 regulates the immune system at multiple points, including class switch recombination (CSR) in activated B cells and the function of T cells in part by restricting their terminal differentiation. However, the regulation of Bach2 expression and its activity in the immune cells are still unclear. Here, we demonstrated that Bach2 mRNA expression decreased in Pten-deficient primary B cells. Bach2 was phosphorylated in primary B cells, which was increased upon the activation of the B cell receptor by an anti-immunoglobulin M (IgM) antibody or CD40 ligand. Using specific inhibitors of kinases, the phosphorylation of Bach2 in activated B cells was shown to depend on the phosphatidylinositol 3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) pathway. The complex of mTOR and Raptor phosphorylated Bach2 in vitro. We identified multiple new phosphorylation sites of Bach2 by mass spectrometry analysis of epitope-tagged Bach2 expressed in the mature B cell line BAL17. Among the sites identified, serine 535 (Ser-535) was critical for the regulation of Bach2 because a single mutation of Ser-535 abolished cytoplasmic accumulation of Bach2, promoting its nuclear accumulation in pre-B cells, whereas Ser-509 played an auxiliary role. Bach2 repressor activity was enhanced by the Ser-535 mutation in B cells. These results suggest that the PI3K-Akt-mTOR pathway inhibits Bach2 by both repressing its expression and inducing its phosphorylation in B cells. PMID:26620562

  19. Interleukin 2 receptors on human B cells. Implications for the role of interleukin 2 in human B cell function

    OpenAIRE

    1985-01-01

    In the present study, we examined the expression of interleukin 2 (IL- 2) receptors on normal human B cells as well as established B cell lines. Anti-Tac monoclonal antibody did not bind to freshly separated normal human B cells. Unexpectedly, with the appropriate activation of the normal B cells by anti-mu antibody, phorbol myristate acetate, or Staphylococcus aureus Cowan I (SAC), Tac antigen was induced on the activated B cells. Anti-Tac antibody showed consistent reactivity with two B cel...

  20. Internet based benchmarking

    DEFF Research Database (Denmark)

    Bogetoft, Peter; Nielsen, Kurt

    2005-01-01

    We discuss the design of interactive, internet based benchmarking using parametric (statistical) as well as nonparametric (DEA) models. The user receives benchmarks and improvement potentials. The user is also given the possibility to search different efficiency frontiers and hereby to explore...

  1. Handleiding benchmark VO

    NARCIS (Netherlands)

    Blank, j.l.t.

    2008-01-01

    OnderzoeksrapportenArchiefTechniek, Bestuur en Management> Over faculteit> Afdelingen> Innovation Systems> IPSE> Onderzoek> Publicaties> Onderzoeksrapporten> Handleiding benchmark VO Handleiding benchmark VO 25 november 2008 door IPSE Studies Door J.L.T. Blank. Handleiding voor het lezen van de i

  2. Benchmark af erhvervsuddannelserne

    DEFF Research Database (Denmark)

    Bogetoft, Peter; Wittrup, Jesper

    I dette arbejdspapir diskuterer vi, hvorledes de danske erhvervsskoler kan benchmarkes, og vi præsenterer resultaterne af en række beregningsmodeller. Det er begrebsmæssigt kompliceret at benchmarke erhvervsskolerne. Skolerne udbyder en lang række forskellige uddannelser. Det gør det vanskeligt...

  3. Immunoinformatics Approach in Designing Epitope-based Vaccine Against Meningitis-inducing Bacteria (Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae Type b)

    Science.gov (United States)

    Zahroh, Hilyatuz; Ma’rup, Ahmad; Tambunan, Usman Sumo Friend; Parikesit, Arli Aditya

    2016-01-01

    Meningitis infection is one of the major threats during Hajj season in Mecca. Meningitis vaccines are available, but their uses are limited in some countries due to religious reasons. Furthermore, they only give protection to certain serogroups, not to all types of meningitis-inducing bacteria. Recently, research on epitope-based vaccines has been developed intensively. Such vaccines have potential advantages over conventional vaccines in that they are safer to use and well responded to the antibody. In this study, we developed epitope-based vaccine candidates against various meningitis-inducing bacteria, including Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae type b. The epitopes were selected from their protein of polysaccharide capsule. B-cell epitopes were predicted by using BCPred, while T-cell epitope for major histocompatibility complex (MHC) class I was predicted using PAProC, TAPPred, and Immune Epitope Database. Immune Epitope Database was also used to predict T-cell epitope for MHC class II. Population coverage and molecular docking simulation were predicted against previously generated epitope vaccine candidates. The best candidates for MHC class I- and class II-restricted T-cell epitopes were MQYGDKTTF, MKEQNTLEI, ECTEGEPDY, DLSIVVPIY, YPMAMMWRNASNRAI, TLQMTLLGIVPNLNK, ETSLHHIPGISNYFI, and SLLYILEKNAEMEFD, which showed 80% population coverage. The complexes of class I T-cell epitopes–HLA-C*03:03 and class II T-cell epitopes–HLA-DRB1*11:01 showed better affinity than standards as evaluated from their ΔGbinding value and the binding interaction between epitopes and HLA molecules. These peptide constructs may further be undergone in vitro and in vivo testings for the development of targeted vaccine against meningitis infection. PMID:27812281

  4. Verification and validation benchmarks.

    Energy Technology Data Exchange (ETDEWEB)

    Oberkampf, William Louis; Trucano, Timothy Guy

    2007-02-01

    Verification and validation (V&V) are the primary means to assess the accuracy and reliability of computational simulations. V&V methods and procedures have fundamentally improved the credibility of simulations in several high-consequence fields, such as nuclear reactor safety, underground nuclear waste storage, and nuclear weapon safety. Although the terminology is not uniform across engineering disciplines, code verification deals with assessing the reliability of the software coding, and solution verification deals with assessing the numerical accuracy of the solution to a computational model. Validation addresses the physics modeling accuracy of a computational simulation by comparing the computational results with experimental data. Code verification benchmarks and validation benchmarks have been constructed for a number of years in every field of computational simulation. However, no comprehensive guidelines have been proposed for the construction and use of V&V benchmarks. For example, the field of nuclear reactor safety has not focused on code verification benchmarks, but it has placed great emphasis on developing validation benchmarks. Many of these validation benchmarks are closely related to the operations of actual reactors at near-safety-critical conditions, as opposed to being more fundamental-physics benchmarks. This paper presents recommendations for the effective design and use of code verification benchmarks based on manufactured solutions, classical analytical solutions, and highly accurate numerical solutions. In addition, this paper presents recommendations for the design and use of validation benchmarks, highlighting the careful design of building-block experiments, the estimation of experimental measurement uncertainty for both inputs and outputs to the code, validation metrics, and the role of model calibration in validation. It is argued that the understanding of predictive capability of a computational model is built on the level of

  5. Initiation of immune tolerance–controlled HIV gp41 neutralizing B cell lineages

    Science.gov (United States)

    Zhang, Ruijun; Verkoczy, Laurent; Wiehe, Kevin; Alam, S. Munir; Nicely, Nathan I.; Santra, Sampa; Bradley, Todd; Pemble, Charles W.; Zhang, Jinsong; Gao, Feng; Montefiori, David C.; Bouton-Verville, Hilary; Kelsoe, Garnett; Larimore, Kevin; Greenberg, Phillip D.; Parks, Robert; Foulger, Andrew; Peel, Jessica N.; Luo, Kan; Lu, Xiaozhi; Trama, Ashley M.; Vandergrift, Nathan; Tomaras, Georgia D.; Kepler, Thomas B.; Moody, M. Anthony; Liao, Hua-Xin; Haynes, Barton F.

    2016-01-01

    Development of an HIV vaccine is a global priority. A major roadblock to a vaccine is an inability to induce protective broadly neutralizing antibodies (bnAbs). HIV gp41 bnAbs have characteristics that predispose them to be controlled by tolerance. We used gp41 2F5 bnAb germline knock-in mice and macaques vaccinated with immunogens reactive with germline precursors to activate neutralizing antibodies. In germline knock-in mice, bnAb precursors were deleted, with remaining anergic B cells capable of being activated by germline-binding immunogens to make gp41-reactive immunoglobulin M (IgM). Immunized macaques made B cell clonal lineages targeted to the 2F5 bnAb epitope, but 2F5-like antibodies were either deleted or did not attain sufficient affinity for gp41-lipid complexes to achieve the neutralization potency of 2F5. Structural analysis of members of a vaccine-induced antibody lineage revealed that heavy chain complementarity-determining region 3 (HCDR3) hydrophobicity was important for neutralization. Thus, gp41 bnAbs are controlled by immune tolerance, requiring vaccination strategies to transiently circumvent tolerance controls. PMID:27122615

  6. Comparison of in vitro immunogenicity, tolerogenicity and mitogenicity of dinitrophenyl-levan conjugates with varying epitope density.

    Science.gov (United States)

    Desaymard, C; Ivanyi, L

    1976-01-01

    The mitogenicity, immunogenicity and tolerogenicity of various DNP-levan (DNP-LE) conjugates were compared using in vitro methods. Anti-DNP antibody synthesis induced by DNP-LE conjugates was related to the epitope density of DNP, BUT WAS NOT AFFECTED BY Macrophage dependent and was not influenced by the degree of hapten conjugation. These results imply that mitogenicity of an antigen is not necessarily related to the specific triggering of B cells. PMID:58831

  7. Regulation of VH replacement by B cell receptor-mediated signaling in human immature B cells.

    Science.gov (United States)

    Liu, Jing; Lange, Miles D; Hong, Sang Yong; Xie, Wanqin; Xu, Kerui; Huang, Lin; Yu, Yangsheng; Ehrhardt, Götz R A; Zemlin, Michael; Burrows, Peter D; Su, Kaihong; Carter, Robert H; Zhang, Zhixin

    2013-06-01

    VH replacement provides a unique RAG-mediated recombination mechanism to edit nonfunctional IgH genes or IgH genes encoding self-reactive BCRs and contributes to the diversification of Ab repertoire in the mouse and human. Currently, it is not clear how VH replacement is regulated during early B lineage cell development. In this article, we show that cross-linking BCRs induces VH replacement in human EU12 μHC(+) cells and in the newly emigrated immature B cells purified from peripheral blood of healthy donors or tonsillar samples. BCR signaling-induced VH replacement is dependent on the activation of Syk and Src kinases but is inhibited by CD19 costimulation, presumably through activation of the PI3K pathway. These results show that VH replacement is regulated by BCR-mediated signaling in human immature B cells, which can be modulated by physiological and pharmacological treatments.

  8. Primary cardiac diffuse large B-cell lymphoma with activated B-cell-like phenotype

    Directory of Open Access Journals (Sweden)

    Vijaya Gadage

    2011-01-01

    Full Text Available Primary cardiac lymphoma (PCL is a rare and fatal disorder. It may often mimic other common cardiac tumors like cardiac myxoma because of similarities in the clinical presentation. We report a case of PCL of diffuse large B-cell type, in a 38-year-old, immunocompetent male who presented with superior vena cava syndrome that was excised as a myxoma. Histology revealed a large cell population diffusely and strongly expressing CD45, CD20, MUM1/IRF4 and FOXP1 hinting at an activated B-cell (ABC-like phenotype. After four cycles of Rituximab with CHOP (cyclophosphamide, hydroxydaunorubicin, Oncovin, and prednisolone the tumor regressed completely but the patient had a relapse and subsequently succumbed to the disease confirming the aggressive nature. The aggressive behavior of PCL may be possibly linked to its ABC-like origin.

  9. Gastrointestinal B-cell lymphomas: From understanding B-cell physiology to classification and molecular pathology

    OpenAIRE

    2012-01-01

    The gut is the most common extranodal site where lymphomas arise. Although all histological lymphoma types may develop in the gut, small and large B-cell lymphomas predominate. The sometimes unexpected finding of a lymphoid lesion in an endoscopic biopsy of the gut may challenge both the clinician (who is not always familiar with lymphoma pathogenesis) and the pathologist (who will often be hampered in his/her diagnostic skill by the limited amount of available tissue). Moreover, the past 2 d...

  10. Differential programming of B cells in AID deficient mice.

    Directory of Open Access Journals (Sweden)

    Marc A Hogenbirk

    Full Text Available The Aicda locus encodes the activation induced cytidine deaminase (AID and is highly expressed in germinal center (GC B cells to initiate somatic hypermutation (SHM and class switch recombination (CSR of immunoglobulin (Ig genes. Besides these Ig specific activities in B cells, AID has been implicated in active DNA demethylation in non-B cell systems. We here determined a potential role of AID as an epigenetic eraser and transcriptional regulator in B cells. RNA-Seq on different B cell subsets revealed that Aicda(-/- B cells are developmentally affected. However as shown by RNA-Seq, MethylCap-Seq, and SNP analysis these transcriptome alterations may not relate to AID, but alternatively to a CBA mouse strain derived region around the targeted Aicda locus. These unexpected confounding parameters provide alternative, AID-independent interpretations on genotype-phenotype correlations previously reported in numerous studies on AID using the Aicda(-/- mouse strain.

  11. Brucella abortus-infected B cells induce osteoclastogenesis.

    Science.gov (United States)

    Pesce Viglietti, Ayelén Ivana; Arriola Benitez, Paula Constanza; Giambartolomei, Guillermo Hernán; Delpino, María Victoria

    2016-09-01

    Brucella abortus is an intracellular bacterium that establishes lifelong infections in livestock and humans although the mechanisms of its chronicity are poorly understood. Activated B cells have long lifespan and B. abortus infection activates B cells. Our results indicate that the direct infection of B cells with B. abortus induced matrix metalloproteinase-9 (MMP-9), receptor activator for NF κB ligand (RANKL), tumor necrosis factor (TNF)-α and interleukin (IL)-6 secretion. In addition, supernatants from B. abortus-infected B cells induced bone marrow-derived monocytes to undergo osteoclastogenesis. Using osteoprotegerin, RANKL's decoy receptor, we determined that RANKL is involved in osteoclastogenesis induced by supernatants from B. abortus-infected B cells. The results presented here shed light on how the interactions of B. abortus with B cells may have a role in the pathogenesis of brucellar osteoarticular disease.

  12. Entry of Francisella tularensis into Murine B Cells: The Role of B Cell Receptors and Complement Receptors.

    Directory of Open Access Journals (Sweden)

    Lenka Plzakova

    Full Text Available Francisella tularensis, the etiological agent of tularemia, is an intracellular pathogen that dominantly infects and proliferates inside phagocytic cells but can be seen also in non-phagocytic cells, including B cells. Although protective immunity is known to be almost exclusively associated with the type 1 pathway of cellular immunity, a significant role of B cells in immune responses already has been demonstrated. Whether their role is associated with antibody-dependent or antibody-independent B cell functions is not yet fully understood. The character of early events during B cell-pathogen interaction may determine the type of B cell response regulating the induction of adaptive immunity. We used fluorescence microscopy and flow cytometry to identify the basic requirements for the entry of F. tularensis into B cells within in vivo and in vitro infection models. Here, we present data showing that Francisella tularensis subsp. holarctica strain LVS significantly infects individual subsets of murine peritoneal B cells early after infection. Depending on a given B cell subset, uptake of Francisella into B cells is mediated by B cell receptors (BCRs with or without complement receptor CR1/2. However, F. tularensis strain FSC200 ΔiglC and ΔftdsbA deletion mutants are defective in the ability to enter B cells. Once internalized into B cells, F. tularensis LVS intracellular trafficking occurs along the endosomal pathway, albeit without significant multiplication. The results strongly suggest that BCRs alone within the B-1a subset can ensure the internalization process while the BCRs on B-1b and B-2 cells need co-signaling from the co receptor containing CR1/2 to initiate F. tularensis engulfment. In this case, fluidity of the surface cell membrane is a prerequisite for the bacteria's internalization. The results substantially underline the functional heterogeneity of B cell subsets in relation to F. tularensis.

  13. Vaccination of mice with plasmids expressing processed capsid protein of foot-and-mouth disease virus - Importance of dominant and subdominant epitopes for antigenicity and protection

    DEFF Research Database (Denmark)

    Frimann, Tine; Barfoed, Annette Malene; Aasted, Bent;

    2007-01-01

    The capsid of foot-and-mouth disease virus (FMDV) displays several independent B cell epitopes, which stimulate the production of neutralising antibodies. Some of these epitopes are highly variable between virus strains, but dominate the immune response. The site A on VP1 is the most prominent...... example of a dominant and variable site. This variability is a problem when designing vaccines against this disease, because it necessitates a close match between vaccine strain and virus in an outbreak. We have introduced a series of mutations into viral capsid proteins with the aim of selectively...... silencing two dominant and highly variable epitopes and thereby divert immune responses toward less dominant but more conserved, protective epitopes. When mice were immunized with modified antigens, the resulting immune responses showed a higher degree of cross-reactivity towards heterologous virus...

  14. Toxicological Benchmarks for Wildlife

    Energy Technology Data Exchange (ETDEWEB)

    Sample, B.E. Opresko, D.M. Suter, G.W.

    1993-01-01

    Ecological risks of environmental contaminants are evaluated by using a two-tiered process. In the first tier, a screening assessment is performed where concentrations of contaminants in the environment are compared to no observed adverse effects level (NOAEL)-based toxicological benchmarks. These benchmarks represent concentrations of chemicals (i.e., concentrations presumed to be nonhazardous to the biota) in environmental media (water, sediment, soil, food, etc.). While exceedance of these benchmarks does not indicate any particular level or type of risk, concentrations below the benchmarks should not result in significant effects. In practice, when contaminant concentrations in food or water resources are less than these toxicological benchmarks, the contaminants may be excluded from further consideration. However, if the concentration of a contaminant exceeds a benchmark, that contaminant should be retained as a contaminant of potential concern (COPC) and investigated further. The second tier in ecological risk assessment, the baseline ecological risk assessment, may use toxicological benchmarks as part of a weight-of-evidence approach (Suter 1993). Under this approach, based toxicological benchmarks are one of several lines of evidence used to support or refute the presence of ecological effects. Other sources of evidence include media toxicity tests, surveys of biota (abundance and diversity), measures of contaminant body burdens, and biomarkers. This report presents NOAEL- and lowest observed adverse effects level (LOAEL)-based toxicological benchmarks for assessment of effects of 85 chemicals on 9 representative mammalian wildlife species (short-tailed shrew, little brown bat, meadow vole, white-footed mouse, cottontail rabbit, mink, red fox, and whitetail deer) or 11 avian wildlife species (American robin, rough-winged swallow, American woodcock, wild turkey, belted kingfisher, great blue heron, barred owl, barn owl, Cooper's hawk, and red

  15. Regulatory T cells and B cells: implication on autoimmune diseases

    OpenAIRE

    Wang, Ping; Zheng, Song Guo

    2013-01-01

    The regulatory T (Treg) cells play an important role in the maintenance of homeostasis and the prevention of autoimmune diseases. Although most studies are focusing on the role of Treg cells in T cells and T cells-mediated diseases, these cells also directly affect B cells and other non-T cells. This manuscript updates the role of Treg cells on the B cells and B cell-mediated diseases. In addition, the mechanisms whereby Treg cells suppress B cell responses have been discussed.

  16. Invited article: inhibition of B cell functions: implications for neurology.

    Science.gov (United States)

    Dalakas, Marinos C

    2008-06-01

    B cells are involved in the pathophysiology of many neurologic diseases, either in a causative or contributory role, via production of autoantibodies, cytokine secretion, or by acting as antigen-presenting cells leading to T cell activation. B cells are clonally expanded in various CNS disorders, such as multiple sclerosis (MS), paraneoplastic CNS disorders, or stiff-person syndrome, and are activated to produce pathogenic autoantibodies in demyelinating neuropathies and myasthenia. B cell activating factor (BAFF) and a proliferating inducing ligand (APRIL), key cytokines for B cell survival, are strongly unregulated in MS brain and in muscles of inflammatory myopathies. Modulation of B cell functions using a series of monoclonal antibodies against CD20+ B cells or the molecules that increase B cell survival, such as BAFF/APRIL and their receptors BAFF-R, TACI, and BCMA, provide a rational approach to the treatment of the aforementioned neurologic disorders. In controlled studies, rituximab, a B cell-depleting monoclonal antibody, has been encouraging in MS and paraproteinemic anti-MAG demyelinating neuropathy, exerting long-lasting remissions. In uncontrolled series, benefit has been reported in several disorders. B cell depletion is a well-tolerated therapeutic option currently explored in the treatment of several autoimmune neurologic disorders.

  17. B cells as a target of immune modulation

    Directory of Open Access Journals (Sweden)

    Hawker Kathleen

    2009-01-01

    Full Text Available B cells have recently been identified as an integral component of the immune system; they play a part in autoimmunity through antigen presentation, antibody secretion, and complement activation. Animal models of multiple sclerosis (MS suggest that myelin destruction is partly mediated through B cell activation (and plasmablasts. MS patients with evidence of B cell involvement, as compared to those without, tend to have a worse prognosis. Finally, the significant decrease in new gadolinium-enhancing lesions, new T2 lesions, and relapses in MS patients treated with rituximab (a monoclonal antibody against CD20 on B cells leads us to the conclusion that B cells play an important role in MS and that immune modulation of these cells may ameliorate the disease. This article will explore the role of B cells in MS and the rationale for the development of B cell-targeted therapeutics. MS is an immune-mediated disease that affects over 2 million people worldwide and is the number one cause of disability in young patients. Most therapeutic targets have focused on T cells; however, recently, the focus has shifted to the role of B cells in the pathogenesis of MS and the potential of B cells as a therapeutic target.

  18. B-Cell Response during Protozoan Parasite Infections

    Directory of Open Access Journals (Sweden)

    María C. Amezcua Vesely

    2012-01-01

    Full Text Available In this review, we discuss how protozoan parasites alter immature and mature B cell compartment. B1 and marginal zone (MZ B cells, considered innate like B cells, are activated during protozoan parasite infections, and they generate short lived plasma cells providing a prompt antibody source. In addition, protozoan infections induce massive B cell response with polyclonal activation that leads to hypergammaglobulnemia with serum antibodies specific for the parasites and self and/or non related antigens. To protect themselves, the parasites have evolved unique ways to evade B cell immune responses inducing apoptosis of MZ and conventional mature B cells. As a consequence of the parasite induced-apoptosis, the early IgM response and an already establish humoral immunity are affected during the protozoan parasite infection. Moreover, some trypanosomatides trigger bone marrow immature B cell apoptosis, influencing the generation of new mature B cells. Simultaneously with their ability to release antibodies, B cells produce cytokines/quemokines that influence the characteristic of cellular immune response and consequently the progression of parasite infections.

  19. GeodeticBenchmark_GEOMON

    Data.gov (United States)

    Vermont Center for Geographic Information — The GeodeticBenchmark_GEOMON data layer consists of geodetic control monuments (points) that have a known position or spatial reference. The locations of these...

  20. Design and Antigenic Epitopes Prediction of a New Trial Recombinant Multiepitopic Rotaviral Vaccine: In Silico Analyses.

    Science.gov (United States)

    Jafarpour, Sima; Ayat, Hoda; Ahadi, Ali Mohammad

    2015-01-01

    Rotavirus is the major etiologic factor of severe diarrheal disease. Natural infection provides protection against subsequent rotavirus infection and diarrhea. This research presents a new vaccine designed based on computational models. In this study, three types of epitopes are considered-linear, conformational, and combinational-in a proposed model protein. Several studies on rotavirus vaccines have shown that VP6 and VP4 proteins are good candidates for vaccine production. In the present study, a fusion protein was designed as a new generation of rotavirus vaccines by bioinformatics analyses. This model-based study using ABCpred, BCPREDS, Bcepred, and Ellipro web servers showed that the peptide presented in this article has the necessary properties to act as a vaccine. Prediction of linear B-cell epitopes of peptides is helpful to investigate whether these peptides are able to activate humoral immunity.

  1. Design and Antigenic Epitopes Prediction of a New Trial Recombinant Multiepitopic Rotaviral Vaccine: In Silico Analyses.

    Science.gov (United States)

    Jafarpour, Sima; Ayat, Hoda; Ahadi, Ali Mohammad

    2015-01-01

    Rotavirus is the major etiologic factor of severe diarrheal disease. Natural infection provides protection against subsequent rotavirus infection and diarrhea. This research presents a new vaccine designed based on computational models. In this study, three types of epitopes are considered-linear, conformational, and combinational-in a proposed model protein. Several studies on rotavirus vaccines have shown that VP6 and VP4 proteins are good candidates for vaccine production. In the present study, a fusion protein was designed as a new generation of rotavirus vaccines by bioinformatics analyses. This model-based study using ABCpred, BCPREDS, Bcepred, and Ellipro web servers showed that the peptide presented in this article has the necessary properties to act as a vaccine. Prediction of linear B-cell epitopes of peptides is helpful to investigate whether these peptides are able to activate humoral immunity. PMID:25965449

  2. How Activists Use Benchmarks

    DEFF Research Database (Denmark)

    Seabrooke, Leonard; Wigan, Duncan

    2015-01-01

    Non-governmental organisations use benchmarks as a form of symbolic violence to place political pressure on firms, states, and international organisations. The development of benchmarks requires three elements: (1) salience, that the community of concern is aware of the issue and views it as impo...... interests and challenge established politico-economic norms. Differentiating these cycles provides insights into how activists work through organisations and with expert networks, as well as how campaigns on complex economic issues can be mounted and sustained....

  3. The B-cell receptor orchestrates environment-mediated lymphoma survival and drug resistance in B-cell malignancies

    OpenAIRE

    Shain, KH; Tao, J.

    2013-01-01

    Specific niches within the lymphoma tumor microenvironment (TME) provide sanctuary for subpopulations of tumor cells through stromal cell–tumor cell interactions. These interactions notably dictate growth, response to therapy and resistance of residual malignant B cells to therapeutic agents. This minimal residual disease (MRD) remains a major challenge in the treatment of B-cell malignancies and contributes to subsequent disease relapse. B-cell receptor (BCR) signaling has emerged as essenti...

  4. B-cell-mediated strategies to fight chronic allograft rejection

    Directory of Open Access Journals (Sweden)

    Ali H Dalloul

    2013-12-01

    Full Text Available Solid organs have been transplanted for decades. Since the improvement in graft selection and in medical and surgical procedures, the likelihood of graft function after one year is now close to 90%. Nonetheless even well-matched recipients continue to need medications for the rest of their lives hence adverse side effects and enhanced morbidity. Understanding Immune rejection mechanisms, is of increasing importance since the greater use of living-unrelated donors and genetically unmatched individuals. Chronic rejection is devoted to T-cells, however the role of B-cells in rejection has been appreciated recently by the observation that B-cell depletion improve graft survival. By contrast however, B-cells can be beneficial to the grafted tissue. This protective effect is secondary to either the secretion of protective antibodies or the induction of B-cells that restrain excessive inflammatory responses, chiefly by local provision of IL-10, or inhibit effector T-cells by direct cellular interactions. As a proof of concept B-cell-mediated infectious transplantation tolerance could be achieved in animal models, and evidence emerged that the presence of such B-cells in transplanted patients correlate with a favorable outcome. Among these populations, regulatory B-cells constitute a recently described population. These cells may develop as a feedback mechanism to prevent uncontrolled reactivity to antigens and inflammatory stimuli. The difficult task for the clinician, is to quantify the respective ratios and functions of tolerant vs effector B-cells within a transplanted organ, at a given time point in order to modulate B-cell-directed therapy. Several receptors at the B-cell membrane as well as signaling molecules, can now be targeted for this purpose. Understanding the temporal expansion of regulatory B-cells in grafted patients and the stimuli that activate them will help in the future to implement specific strategies aimed at fighting chronic

  5. BAFF enhances chemotaxis of primary human B cells: a particular synergy between BAFF and CXCL13 on memory B cells.

    Science.gov (United States)

    Badr, Gamal; Borhis, Gwenoline; Lefevre, Eric A; Chaoul, Nada; Deshayes, Frederique; Dessirier, Valérie; Lapree, Genevieve; Tsapis, Andreas; Richard, Yolande

    2008-03-01

    B-cell-activating factor of the TNF family, (BAFF), and a proliferation-inducing ligand (APRIL) regulate B-lymphocyte survival and activation. We report that BAFF, but not APRIL, increased the chemotactic response of primary human B cells to CCL21, CXCL12, and CXCL13. The BAFF-induced increase in B-cell chemotaxis was totally abolished by blockade of BAFF-R and was strongly dependent on the activation of PI3K/AKT, NF-kappaB, and p38MAPK pathways. BAFF had similar effects on the chemotaxis of naive and memory B cells in response to CCL21 but increased more strongly that of memory B cells to CXCL13 than that of naive B cells. Our findings indicate a previously unreported role for the BAFF/BAFF-R pair in mature B-cell chemotaxis. The synergy between CXCL13 and BAFF produced by stromal cells and follicular dendritic cells may have important implications for B-cell homeostasis, the development of normal B-cell areas, and for the formation of germinal center-like follicles that may be observed in various autoimmune diseases.

  6. Tissue-specific B-cell dysfunction and generalized memory B-cell loss during acute SIV infection.

    Directory of Open Access Journals (Sweden)

    Sandrine Peruchon

    Full Text Available BACKGROUND: Primary HIV-infected patients display severe and irreversible damage to different blood B-cell subsets which is not restored by highly efficient anti-retroviral therapy (HAART. Because longitudinal investigations of primary HIV-infection is limited by the availability of lymphoid organs, we studied the tissue-specific B-cell dysfunctions in acutely simian immunodeficiency virus (SIV mac251-infected Cynomolgus macaques. METHODS AND FINDINGS: Experiments were performed on three groups of macaques infected for 14, 21 or 28 days and on three groups of animals treated with HAART for two-weeks either initiated at 4 h, 7 or 14 days post-infection (p.i.. We have simultaneously compared changes in B-cell phenotypes and functions and tissue organization of B-cell areas in various lymphoid organs. We showed that SIV induced a steady decline in SIgG-expressing memory (SIgD(-CD27(+ B-cells in spleen and lymph nodes during the first 4 weeks of infection, concomitant to selective homing/sequestration of B-cells to the small intestine and spleen. SIV non-specific Ig production was transiently increased before D14p.i., whereas SIV-specific Ig production was only detectable after D14p.i., coinciding with the presence of CD8(+ T-cells and IgG-expressing plasma cells within germinal centres. Transient B-cell apoptosis on D14p.i. and commitment to terminal differentiation contributed to memory B-cell loss. HAART abrogated B-cell apoptosis, homing to the small intestine and SIV-specific Ig production but had minimal effect on early Ig production, increased B-cell proportions in spleen and loss of memory B-cells. Therefore, virus-B-cell interactions and SIV-induced inflammatory cytokines may differently contribute to early B-cell dysfunction and impaired SIV/HIV-specific antibody response. CONCLUSIONS: These data establish tissue-specific impairments in B-cell trafficking and functions and a generalized and steady memory B-cell loss in secondary lymphoid

  7. A transplant "immunome" screening platform defines a targetable epitope fingerprint of multiple myeloma.

    Science.gov (United States)

    Schieferdecker, Aneta; Oberle, Anna; Thiele, Benjamin; Hofmann, Fabian; Göthel, Markus; Miethe, Sebastian; Hust, Michael; Braig, Friederike; Voigt, Mareike; von Pein, Ute-Marie; Koch-Nolte, Friedrich; Haag, Friedrich; Alawi, Malik; Indenbirken, Daniela; Grundhoff, Adam; Bokemeyer, Carsten; Bacher, Ulrike; Kröger, Nicolaus; Binder, Mascha

    2016-06-23

    Multiple myeloma (MM) is a hematological cancer for which immune-based treatments are currently in development. Many of these rely on the identification of highly disease-specific, strongly and stably expressed antigens. Here, we profiled the myeloma B-cell immunome both to explore its predictive role in the context of autologous and allogeneic hematopoietic stem cell transplantation (HSCT) and to identify novel immunotherapeutic targets. We used random peptide phage display, reverse immunization, and next-generation sequencing-assisted antibody phage display to establish a highly myeloma-specific epitope fingerprint targeted by B-cell responses of 18 patients in clinical remission. We found that allogeneic HSCT more efficiently allowed production of myeloma-specific antibodies compared with autologous HSCT and that a highly reactive epitope recognition signature correlated with superior response to treatment. Next, we performed myeloma cell surface screenings of phage-displayed patient transplant immunomes. Although some of the screenings yielded clear-cut surface binders, the majority of screenings did not, suggesting that many of the targeted antigens may in fact not be accessible to the B-cell immune system in untreated myeloma cells. This fit well with the identification of heat-shock proteins as a class of antigens that showed overall the broadest reactivity with myeloma patient sera after allogeneic HSCT and that may be significantly translocated to the cell surface upon treatment as a result of immunogenic cell death. Our data reveal a disease-specific epitope signature of MM that is predictive for response to treatment. Mining of transplant immunomes for strong myeloma surface binders may open up avenues for myeloma immunotherapy. PMID:27034429

  8. Therapeutic polypeptides based on HBV core 18-27 epitope can induce CD8+ CTL-mediated cytotoxicity in HLA-A2+ human PBMCs

    Institute of Scientific and Technical Information of China (English)

    Tong-Dong Shi; Yu-Zhang Wu; Zheng-Cai Jia; Li-Yun Zou; Wei Zhou

    2004-01-01

    AIM: To explore how to improve the immunogenicity of HBcAg CTL epitope based polypeptides and to trigger an HBV-specific HLA I-restricted CD8+ T cell response in vitro.METHODS: A new panel of mimetic therapeutic peptides based on the immunodominant B cell epitope of HBV PreS218-24 region, the CTL epitope of HBcAg18-27 and the universal T helper epitope of tetanus toxoid (TT) 830-843was designed using computerized molecular design method and synthesized by Merrifield's solid-phase peptide synthesis.Their immunological properties of stimulating activation and proliferation of lymphocytes, of inducing TH1 polarization,CD8+ T cell magnification and HBV-specific CD8+ CTL mediated cytotoxicity were investigatedin vitro using HLAA2+ human peripheral blood mononuclear cells (PBMCs) from healthy donors and chronic hepatitis B patients.RESULTS: Results demonstrated that the therapeutic polypeptides based on immunodominant HBcAg18-27 CTL,PreS2 B- and universal TH epitopes could stimulate the activation and proliferation of lymphocytes, induce specifically and effectively CD8+ T cell expansion and vigorous HBVspecific CTL-mediated cytotoxicity in human PBMCs.CONCLUSION: It indicated that the introduction of immunodominant T helper plus B-epitopes with short and flexible linkers could dramatically improve the immunogenicity of short CTL epitopes in vitro.

  9. The KMAT: Benchmarking Knowledge Management.

    Science.gov (United States)

    de Jager, Martha

    Provides an overview of knowledge management and benchmarking, including the benefits and methods of benchmarking (e.g., competitive, cooperative, collaborative, and internal benchmarking). Arthur Andersen's KMAT (Knowledge Management Assessment Tool) is described. The KMAT is a collaborative benchmarking tool, designed to help organizations make…

  10. Induction of multi-epitope specific antibodies against HIV-1 by multi-epitope vaccines

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Some neutralizing antibodies against HIV-1 envelope proteins were highly effective to inhibit the infection of different strains in vitro, and existed in the infected individuals with very low levels. We suggested multi-epitope-vaccine as a new strategy to increase levels of neutralizing antibodies and the abilities against HIV mutation in vivo. Two candidate multi-epitope-vaccines induced antibodies with predefined multi-epitope-specificity in rhesus macaque. These antibodies recognized corresponding neutralizing epitopes on epitope-peptides, gp41 peptides, V3 loop peptide, rsgp41 and rgp120. Besides, three candidate epitope-vaccines in combination (another kind of multi-epitopevaccines) showed similar potency to induce predefined multiple immune responses in rabbits. These results suggest that multi-epitope-vaccines may be a new strategy to induce multi-antiviral activities against HIV-1 infection and mutafions.

  11. A Novel Algorithm for Macromolecular Epitope Matching

    Directory of Open Access Journals (Sweden)

    Stanislav Jakuschev

    2009-03-01

    Full Text Available Many macromolecules, namely proteins, show functional substructures or epitopes defined by characteristic spatial arrangements of groups of specific atoms or residues. The identification of such substructures in a set of macromolecular 3D-structures solves an important problem in molecular biology as it allows the assignment of functions to molecular moieties and thus opens the possibility of a mechanistic understanding of molecular function. We have devised an algorithm that models a functional epitope formed by a group of atoms or residues as set of points in cartesian space with associated functional properties. The algorithm searches for similar epitopes in a database of structures by an efficient multistage comparison of distance sets in the epitope and in the structures from the database. The search results in a list of optimal matches and corresponding optimal superpositions of query epitope and matching epitopes from the database. The algorithm is discussed against the background of related approaches, and it is successfully tested in three application scenarios: global match of two homologous proteins, search for an epitope on a homologous protein, and finding matching epitopes in a protein database.

  12. B cells as therapeutic targets in autoimmune neurological disorders.

    Science.gov (United States)

    Dalakas, Marinos C

    2008-10-01

    B cells have a fundamental role in the pathogenesis of various autoimmune neurological disorders, not only as precursors of antibody-producing cells, but also as important regulators of the T-cell activation process through their participation in antigen presentation, cytokine production, and formation of ectopic germinal centers in the intermeningeal spaces. Two B-cell trophic factors-BAFF (B-cell-activating factor) and APRIL (a proliferation-inducing ligand)-and their receptors are strongly upregulated in many immunological disorders of the CNS and PNS, and these molecules contribute to clonal expansion of B cells in situ. The availability of monoclonal antibodies or fusion proteins against B-cell surface molecules and trophic factors provides a rational approach to the treatment of autoimmune neurological diseases. This article reviews the role of B cells in autoimmune neurological disorders and summarizes the experience to date with rituximab, a B-cell-depleting monoclonal antibody against CD20, for the treatment of relapsing-remitting multiple sclerosis, autoimmune neuropathies, neuromyelitis optica, paraneoplastic neurological disorders, myasthenia gravis, and inflammatory myopathies. It is expected that ongoing controlled trials will establish the efficacy and long-term safety profile of anti-B-cell agents in several autoimmune neurological disorders, as well as exploring the possibility of a safe and synergistic effect with other immunosuppressants or immunomodulators.

  13. Therapeutic strategies targeting B-cells in multiple sclerosis.

    Science.gov (United States)

    Milo, Ron

    2016-07-01

    Multiple sclerosis (MS) is a chronic inflammatory and demyelinating disease of the central nervous system (CNS) that traditionally has been considered to be mediated primarily by T-cells. Increasing evidence, however, suggests the fundamental role of B-cells in the pathogenesis of the disease. Recent strategies targeting B-cells in MS have demonstrated impressive and sometimes surprising results: B-cell depletion by monoclonal antibodies targeting the B-cell surface antigen CD20 (e.g. rituximab, ocrelizumab, ofatumumab) was shown to exert profound anti-inflammatory effect in MS with favorable risk-benefit ratio, with ocrelizumab demonstrating efficacy in both relapsing-remitting (RR) and primary-progressive (PP) MS in phase III clinical trials. Depletion of CD52 expressing T- and B-cells and monocytes by alemtuzumab resulted in impressive and durable suppression of disease activity in RRMS patients. On the other hand, strategies targeting B-cell cytokines such as atacicept resulted in increased disease activity. As our understanding of the biology of B-cells in MS is increasing, new compounds that target B-cells continue to be developed which promise to further expand the armamentarium of MS therapies and allow for more individualized therapy for patients with this complex disease.

  14. DNA breaks early in replication in B cell cancers

    Science.gov (United States)

    Research by scientists at the NCI has identified a new class of DNA sites in cells that break early in the replication process. They found that these break sites correlate with damage often seen in B cell cancers, such as diffuse large B cell lymphoma.

  15. Shaping T Cell – B Cell Collaboration in the Response to Human Immunodeficiency Virus Type 1 Envelope Glycoprotein gp120 by Peptide Priming

    Science.gov (United States)

    Steede, N. Kalaya; Rust, Blake J.; Hossain, Mohammad M.; Freytag, Lucy C.; Robinson, James E.; Landry, Samuel J.

    2013-01-01

    Prime-boost vaccination regimes have shown promise for obtaining protective immunity to HIV. Poorly understood mechanisms of cellular immunity could be responsible for improved humoral responses. Although CD4+ T-cell help promotes B-cell development, the relationship of CD4+ T-cell specificity to antibody specificity has not been systematically investigated. Here, protein and peptide-specific immune responses to HIV-1 gp120 were characterized in groups of ten mucosally immunized BALB/c mice. Protein and peptide reactivity of serum antibody was tested for correlation with cytokine secretion by splenocytes restimulated with individual gp120 peptides. Antibody titer for gp120 correlated poorly with the peptide-stimulated T-cell response. In contrast, titers for conformational epitopes, measured as crossreactivity or CD4-blocking, correlated with average interleukin-2 and interleukin-5 production in response to gp120 peptides. Antibodies specific for conformational epitopes and individual gp120 peptides typically correlated with T-cell responses to several peptides. In order to modify the specificity of immune responses, animals were primed with a gp120 peptide prior to immunization with protein. Priming induced distinct peptide-specific correlations of antibodies and T-cells. The majority of correlated antibodies were specific for the primed peptides or other peptides nearby in the gp120 sequence. These studies suggest that the dominant B-cell subsets recruit the dominant T-cell subsets and that T-B collaborations can be shaped by epitope-specific priming. PMID:23776539

  16. Shaping T cell - B cell collaboration in the response to human immunodeficiency virus type 1 envelope glycoprotein gp120 by peptide priming.

    Directory of Open Access Journals (Sweden)

    N Kalaya Steede

    Full Text Available Prime-boost vaccination regimes have shown promise for obtaining protective immunity to HIV. Poorly understood mechanisms of cellular immunity could be responsible for improved humoral responses. Although CD4+ T-cell help promotes B-cell development, the relationship of CD4+ T-cell specificity to antibody specificity has not been systematically investigated. Here, protein and peptide-specific immune responses to HIV-1 gp120 were characterized in groups of ten mucosally immunized BALB/c mice. Protein and peptide reactivity of serum antibody was tested for correlation with cytokine secretion by splenocytes restimulated with individual gp120 peptides. Antibody titer for gp120 correlated poorly with the peptide-stimulated T-cell response. In contrast, titers for conformational epitopes, measured as crossreactivity or CD4-blocking, correlated with average interleukin-2 and interleukin-5 production in response to gp120 peptides. Antibodies specific for conformational epitopes and individual gp120 peptides typically correlated with T-cell responses to several peptides. In order to modify the specificity of immune responses, animals were primed with a gp120 peptide prior to immunization with protein. Priming induced distinct peptide-specific correlations of antibodies and T-cells. The majority of correlated antibodies were specific for the primed peptides or other peptides nearby in the gp120 sequence. These studies suggest that the dominant B-cell subsets recruit the dominant T-cell subsets and that T-B collaborations can be shaped by epitope-specific priming.

  17. B-Cell Pathology in Juvenile Idiopathic Arthritis

    Directory of Open Access Journals (Sweden)

    V. Wiegering

    2010-01-01

    Full Text Available Juvenile Idiopathic Arthritis (JIA is the most common cause of chronic arthritis in childhood and adolescents and encompasses a heterogeneous group of different diseases. Due to the promising results of B-cell depleting therapies in rheumatoid arthritis the role of B-cells in autoimmune diseases has to be discussed in a new context. Additionally, experiments in mouse models have shed new light on the antibody-independent role of B-cells in the development of autoimmune diseases. In this review we will discuss the importance of B-cells in the pathogenesis of JIA appraising the question for an immunological basis of B-cell targeted therapy in JIA.

  18. Anti-B cell antibody therapies for inflammatory rheumatic diseases

    DEFF Research Database (Denmark)

    Faurschou, Mikkel; Jayne, David R W

    2014-01-01

    Several monoclonal antibodies targeting B cells have been tested as therapeutics for inflammatory rheumatic diseases. We review important observations from randomized clinical trials regarding the efficacy and safety of anti-B cell antibody-based therapies for rheumatoid arthritis, systemic lupus...... erythematosus, antineutrophil cytoplasmic antibody-associated vasculitis, polymyositis/dermatomyositis, and primary Sjögren's syndrome. For some anti-B cell agents, clinical benefits have been convincingly demonstrated, while other B cell-targeted therapies failed to improve outcomes when added to standard...... and functions in rheumatic disorders. Future studies should also evaluate how to maintain disease control by means of conventional and/or biologic immunosuppressants after remission-induction with anti-B cell antibodies....

  19. Benchmarking the Netherlands. Benchmarking for growth

    International Nuclear Information System (INIS)

    This is the fourth edition of the Ministry of Economic Affairs' publication 'Benchmarking the Netherlands', which aims to assess the competitiveness of the Dutch economy. The methodology and objective of the benchmarking remain the same. The basic conditions for economic activity (institutions, regulation, etc.) in a number of benchmark countries are compared in order to learn from the solutions found by other countries for common economic problems. This publication is devoted entirely to the potential output of the Dutch economy. In other words, its ability to achieve sustainable growth and create work over a longer period without capacity becoming an obstacle. This is important because economic growth is needed to increase prosperity in the broad sense and meeting social needs. Prosperity in both a material (per capita GDP) and immaterial (living environment, environment, health, etc) sense, in other words. The economy's potential output is determined by two structural factors: the growth of potential employment and the structural increase in labour productivity. Analysis by the Netherlands Bureau for Economic Policy Analysis (CPB) shows that in recent years the increase in the capacity for economic growth has been realised mainly by increasing the supply of labour and reducing the equilibrium unemployment rate. In view of the ageing of the population in the coming years and decades the supply of labour is unlikely to continue growing at the pace we have become accustomed to in recent years. According to a number of recent studies, to achieve a respectable rate of sustainable economic growth the aim will therefore have to be to increase labour productivity. To realise this we have to focus on for six pillars of economic policy: (1) human capital, (2) functioning of markets, (3) entrepreneurship, (4) spatial planning, (5) innovation, and (6) sustainability. These six pillars determine the course for economic policy aiming at higher productivity growth. Throughout

  20. Benchmarking in Mobarakeh Steel Company

    Directory of Open Access Journals (Sweden)

    Sasan Ghasemi

    2008-05-01

    Full Text Available Benchmarking is considered as one of the most effective ways of improving performance incompanies. Although benchmarking in business organizations is a relatively new concept and practice, ithas rapidly gained acceptance worldwide. This paper introduces the benchmarking project conducted in Esfahan’s Mobarakeh Steel Company, as the first systematic benchmarking project conducted in Iran. It aimsto share the process deployed for the benchmarking project in this company and illustrate how the projectsystematic implementation led to succes.

  1. Memory B cell antibodies to HIV-1 gp140 cloned from individuals infected with clade A and B viruses.

    Directory of Open Access Journals (Sweden)

    Hugo Mouquet

    Full Text Available Understanding the antibody response to HIV-1 in humans that show broad neutralizing serologic activity is a crucial step in trying to reproduce such responses by vaccination. Investigating antibodies with cross clade reactivity is particularly important as these antibodies may target conserved epitopes on the HIV envelope gp160 protein. To this end we have used a clade B YU-2 gp140 trimeric antigen and single-cell antibody cloning methods to obtain 189 new anti-gp140 antibodies representing 51 independent B cell clones from the IgG memory B cells of 3 patients infected with HIV-1 clade A or B viruses and exhibiting broad neutralizing serologic activity. Our results support previous findings showing a diverse antibody response to HIV gp140 envelope protein, characterized by differentially expanded B-cell clones producing highly hypermutated antibodies with heterogenous gp140-specificity and neutralizing activity. In addition to their high-affinity binding to the HIV spike, the vast majority of the new anti-gp140 antibodies are also polyreactive. Although none of the new antibodies are as broad or potent as VRC01 or PG9, two clonally-related antibodies isolated from a clade A HIV-1 infected donor, directed against the gp120 variable loop 3, rank in the top 5% of the neutralizers identified in our large collection of 185 unique gp140-specific antibodies in terms of breadth and potency.

  2. CD83 Modulates B Cell Activation and Germinal Center Responses.

    Science.gov (United States)

    Krzyzak, Lena; Seitz, Christine; Urbat, Anne; Hutzler, Stefan; Ostalecki, Christian; Gläsner, Joachim; Hiergeist, Andreas; Gessner, André; Winkler, Thomas H; Steinkasserer, Alexander; Nitschke, Lars

    2016-05-01

    CD83 is a maturation marker for dendritic cells. In the B cell lineage, CD83 is expressed especially on activated B cells and on light zone B cells during the germinal center (GC) reaction. The function of CD83 during GC responses is unclear. CD83(-/-) mice have a strong reduction of CD4(+) T cells, which makes it difficult to analyze a functional role of CD83 on B cells during GC responses. Therefore, in the present study we generated a B cell-specific CD83 conditional knockout (CD83 B-cKO) model. CD83 B-cKO B cells show defective upregulation of MHC class II and CD86 expression and impaired proliferation after different stimuli. Analyses of GC responses after immunization with various Ags revealed a characteristic shift in dark zone and light zone B cell numbers, with an increase of B cells in the dark zone of CD83 B-cKO mice. This effect was not accompanied by alterations in the level of IgG immune responses or by major differences in affinity maturation. However, an enhanced IgE response was observed in CD83 B-cKO mice. Additionally, we observed a strong competitive disadvantage of CD83-cKO B cells in GC responses in mixed bone marrow chimeras. Furthermore, infection of mice with Borrelia burgdorferi revealed a defect in bacterial clearance of CD83 B-cKO mice with a shift toward a Th2 response, indicated by a strong increase in IgE titers. Taken together, our results show that CD83 is important for B cell activation and modulates GC composition and IgE Ab responses in vivo. PMID:26983787

  3. Prolactin Rescues Immature B-Cells from Apoptosis Induced by B-Cell Receptor Cross-Linking

    Directory of Open Access Journals (Sweden)

    Rocio Flores-Fernández

    2016-01-01

    Full Text Available Prolactin has an immunomodulatory effect and has been associated with B-cell-triggered autoimmune diseases, such as systemic lupus erythematosus (SLE. In mice that develop SLE, the PRL receptor is expressed in early bone marrow B-cells, and increased levels of PRL hasten disease manifestations, which are correlated with a reduction in the absolute number of immature B-cells. The aim of this work was to determine the effect of PRL in an in vitro system of B-cell tolerance using WEHI-231 cells and immature B-cells from lupus prone MRL/lpr mice. WEHI-231 cells express the long isoform of the PRL receptor, and PRL rescued the cells from cell death by decreasing the apoptosis induced by the cross-linking of the B-cell antigen receptor (BCR as measured by Annexin V and active caspase-3. This decrease in apoptosis may have been due to the PRL and receptor interaction, which increased the relative expression of antiapoptotic Bcl-xL and decreased the relative expression of proapoptotic Bad. In immature B-cells from MRL/lpr mice, PRL increased the viability and decreased the apoptosis induced by the cross-linking of BCR, which may favor the maturation of self-reactive B-cells and contribute to the onset of disease.

  4. Myeloma clonotypic B cells are hampered in their ability to undergo B-cell differentiation in vitro

    NARCIS (Netherlands)

    Guikema, JEJ; Vellenga, E; Bakkus, MHC; Bos, NA

    2002-01-01

    In the peripheral blood (PB) of multiple myeloma (MM) patients, clonotypic B cells are present that express the identical V( D) J rearrangements as the malignant plasma cells in the bone marrow. In the present study, the proliferative capacity of clonotypic B cells from MM patients (n = 10) and the

  5. Prolactin Rescues Immature B-Cells from Apoptosis Induced by B-Cell Receptor Cross-Linking

    Science.gov (United States)

    Flores-Fernández, Rocio; Blanco-Favela, Francisco; Fuentes-Pananá, Ezequiel M.; Chávez-Sánchez, Luis; Gorocica-Rosete, Patricia; Pizaña-Venegas, Alberto; Chávez-Rueda, Adriana Karina

    2016-01-01

    Prolactin has an immunomodulatory effect and has been associated with B-cell-triggered autoimmune diseases, such as systemic lupus erythematosus (SLE). In mice that develop SLE, the PRL receptor is expressed in early bone marrow B-cells, and increased levels of PRL hasten disease manifestations, which are correlated with a reduction in the absolute number of immature B-cells. The aim of this work was to determine the effect of PRL in an in vitro system of B-cell tolerance using WEHI-231 cells and immature B-cells from lupus prone MRL/lpr mice. WEHI-231 cells express the long isoform of the PRL receptor, and PRL rescued the cells from cell death by decreasing the apoptosis induced by the cross-linking of the B-cell antigen receptor (BCR) as measured by Annexin V and active caspase-3. This decrease in apoptosis may have been due to the PRL and receptor interaction, which increased the relative expression of antiapoptotic Bcl-xL and decreased the relative expression of proapoptotic Bad. In immature B-cells from MRL/lpr mice, PRL increased the viability and decreased the apoptosis induced by the cross-linking of BCR, which may favor the maturation of self-reactive B-cells and contribute to the onset of disease. PMID:27314053

  6. B-cell receptor signaling inhibitors for treatment of autoimmune inflammatory diseases and B-cell malignancies.

    Science.gov (United States)

    Puri, Kamal D; Di Paolo, Julie A; Gold, Michael R

    2013-08-01

    B-cell receptor (BCR) signaling is essential for normal B-cell development, selection, survival, proliferation, and differentiation into antibody-secreting cells. Similarly, this pathway plays a key role in the pathogenesis of multiple B-cell malignancies. Genetic and pharmacological approaches have established an important role for the Spleen tyrosine kinase (Syk), Bruton's tyrosine kinase (Btk), and phosphatidylinositol 3-kinase isoform p110delta (PI3Kδ) in coupling the BCR and other BCRs to B-cell survival, migration, and activation. In the past few years, several small-molecule inhibitory drugs that target PI3Kδ, Btk, and Syk have been developed and shown to have efficacy in clinical trials for the treatment of several types of B-cell malignancies. Emerging preclinical data have also shown a critical role of BCR signaling in the activation and function of self-reactive B cells that contribute to autoimmune diseases. Because BCR signaling plays a major role in both B-cell-mediated autoimmune inflammation and B-cell malignancies, inhibition of this pathway may represent a promising new strategy for treating these diseases. This review summarizes recent achievements in the mechanism of action, pharmacological properties, and clinical activity and toxicity of these BCR signaling inhibitors, with a focus on their emerging role in treating lymphoid malignancies and autoimmune disorders.

  7. Bioinformatics prediction on glutathione S-transferase antigen epitopes of Echinoccocus granulosus%细粒棘球蚴 GST 抗原表位的生物信息学预测∗

    Institute of Scientific and Technical Information of China (English)

    李宗吉; 楚元奎; 于欣; 丁淑琴; 刘学英; 赵巍

    2015-01-01

    Objective To analyse the secondary structure of glutathions S-transferase of Echinoccocus granulosus(EgGST)and predict the B cell and T cell epitopes with informatics tools,in order to provide basic data and references for the following design of epitope vaccine.Methods The B cell and T cell epitopes of EgGST were predicted by DNAstar,Biosun software and Propred MHC class-Ⅱ Binding Peptide Prediction Server software.Results Many distinct antigenic epitopes of EgGST were identified by comput-er,there existed 8 B cell epitopes and 7 T cell epitopes.Conclusion Analysis of predicted epitopes of EgGST antigenic might be sig-nificant for future research of epitope vaccine.%目的:应用生物信息软件分析细粒棘球蚴谷胱甘肽 S-转移酶(EgGST)的蛋白二级结构并预测 B 淋巴细胞表位和 T淋巴细胞表位,为后续表位疫苗的设计研究提供基本的数据和资料。方法采用 DNAstar 软件、ProPred MHC Class-Ⅱ Binding Peptide Prediction Server 和 Biosun 软件对 EgGST 的 B 淋巴细胞表位和 T 淋巴细胞表位进行预测。结果预测 EgGST 存在8个 B 淋巴细胞表位区域和7个 T 淋巴细胞表位。结论分析预测的 EgGST 抗原表位将对后续的表位疫苗研究具有重要意义。

  8. Benchmarking for plant maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Komonen, K.; Ahonen, T.; Kunttu, S. (VTT Technical Research Centre of Finland, Espoo (Finland))

    2010-05-15

    The product of the project, e-Famemain, is a new kind of tool for benchmarking, which is based on many years' research efforts within Finnish industry. It helps to evaluate plants' performance in operations and maintenance by making industrial plants comparable with the aid of statistical methods. The system is updated continually and automatically. It carries out automatically multivariate statistical analysis when data is entered into system, and many other statistical operations. Many studies within Finnish industry during the last ten years have revealed clear causalities between various performance indicators. In addition, these causalities should be taken into account when utilising benchmarking or forecasting indicator values e.g. for new investments. The benchmarking system consists of five sections: data input section, positioning section, locating differences section, best practices and planning section and finally statistical tables. (orig.)

  9. Deviating From the Benchmarks

    DEFF Research Database (Denmark)

    Rocha, Vera; Van Praag, Mirjam; Carneiro, Anabela

    This paper studies three related questions: To what extent otherwise similar startups employ different quantities and qualities of human capital at the moment of entry? How persistent are initial human capital choices over time? And how does deviating from human capital benchmarks influence firm......, founders human capital, and the ownership structure of startups (solo entrepreneurs versus entrepreneurial teams). We then study the survival implications of exogenous deviations from these benchmarks, based on spline models for survival data. Our results indicate that (especially negative) deviations from...... the benchmark can be substantial, are persistent over time, and hinder the survival of firms. The implications may, however, vary according to the sector and the ownership structure at entry. Given the stickiness of initial choices, wrong human capital decisions at entry turn out to be a close to irreversible...

  10. Evaluation and use of in-silico structure-based epitope prediction with foot-and-mouth disease virus.

    Directory of Open Access Journals (Sweden)

    Daryl W Borley

    Full Text Available Understanding virus antigenicity is of fundamental importance for the development of better, more cross-reactive vaccines. However, as far as we are aware, no systematic work has yet been conducted using the 3D structure of a virus to identify novel epitopes. Therefore we have extended several existing structural prediction algorithms to build a method for identifying epitopes on the appropriate outer surface of intact virus capsids (which are structurally different from globular proteins in both shape and arrangement of multiple repeated elements and applied it here as a proof of principle concept to the capsid of foot-and-mouth disease virus (FMDV. We have analysed how reliably several freely available structure-based B cell epitope prediction programs can identify already known viral epitopes of FMDV in the context of the viral capsid. To do this we constructed a simple objective metric to measure the sensitivity and discrimination of such algorithms. After optimising the parameters for five methods using an independent training set we used this measure to evaluate the methods. Individually any one algorithm performed rather poorly (three performing better than the other two suggesting that there may be value in developing virus-specific software. Taking a very conservative approach requiring a consensus between all three top methods predicts a number of previously described antigenic residues as potential epitopes on more than one serotype of FMDV, consistent with experimental results. The consensus results identified novel residues as potential epitopes on more than one serotype. These include residues 190-192 of VP2 (not previously determined to be antigenic, residues 69-71 and 193-197 of VP3 spanning the pentamer-pentamer interface, and another region incorporating residues 83, 84 and 169-174 of VP1 (all only previously experimentally defined on serotype A. The computer programs needed to create a semi-automated procedure for carrying out

  11. Phenotypic characterization of autoreactive B cells--checkpoints of B cell tolerance in patients with systemic lupus erythematosus.

    Directory of Open Access Journals (Sweden)

    Annett M Jacobi

    Full Text Available DNA-reactive B cells play a central role in systemic lupus erythematosus (SLE; DNA antibodies precede clinical disease and in established disease correlate with renal inflammation and contribute to dendritic cell activation and high levels of type 1 interferon. A number of central and peripheral B cell tolerance mechanisms designed to control the survival, differentiation and activation of autoreactive B cells are thought to be disturbed in patients with SLE. The characterization of DNA-reactive B cells has, however, been limited by their low frequency in peripheral blood. Using a tetrameric configuration of a peptide mimetope of DNA bound by pathogenic anti-DNA antibodies, we can identify B cells producing potentially pathogenic DNA-reactive antibodies. We, therefore, characterized the maturation and differentiation states of peptide, (ds double stranded DNA cross-reactive B cells in the peripheral blood of lupus patients and correlated these with clinical disease activity. Flow cytometric analysis demonstrated a significantly higher frequency of tetramer-binding B cells in SLE patients compared to healthy controls. We demonstrated the existence of a novel tolerance checkpoint at the transition of antigen-naïve to antigen-experienced. We further demonstrate that patients with moderately active disease have more autoreactive B cells in both the antigen-naïve and antigen-experienced compartments consistent with greater impairment in B cell tolerance in both early and late checkpoints in these patients than in patients with quiescent disease. This methodology enables us to gain insight into the development and fate of DNA-reactive B cells in individual patients with SLE and paves the way ultimately to permit better and more customized therapies.

  12. Exploiting human memory B cell heterogeneity for improved vaccine efficacy

    Directory of Open Access Journals (Sweden)

    Noel Thomas Pauli

    2011-12-01

    Full Text Available The major goal in vaccination is establishment of long-term, prophylactic humoral memory to a pathogen. Two major components to long-lived humoral memory are plasma cells for the production of specific immunoglobulin and memory B cells that survey for their specific antigen in the periphery for later affinity maturation, proliferation, and differentiation. The study of human B cell memory has been aided by the discovery of a general marker for B cell memory, expression of CD27; however, new data suggests the existence of CD27- memory B cells as well. These recently described non-canonical memory populations have increasingly pointed to the heterogeneity of the memory compartment. The novel B memory subsets in humans appear to have unique origins, localization, and functions compared to what was considered to be a classical memory B cell. In this article, we review the known B cell memory subsets, the establishment of B cell memory in vaccination and infection, and how understanding these newly described subsets can inform vaccine design and disease treatment.

  13. Salmonella induces PD-L1 expression in B cells.

    Science.gov (United States)

    Lopez-Medina, Marcela; Perez-Lopez, Araceli; Alpuche-Aranda, Celia; Ortiz-Navarrete, Vianney

    2015-10-01

    Salmonella persists for a long time in B cells; however, the mechanism(s) through which infected B cells avoid effector CD8 T cell responses has not been characterized. In this study, we show that Salmonella infects and survives within all B1 and B2 cell subpopulations. B cells are infected with a Salmonella typhimurium strain expressing an ovalbumin (OVA) peptide (SIINFEKL) to evaluate whether B cells process and present Salmonella antigens in the context of MHC-I molecules. Our data showed that OVA peptides are presented by MHC class I K(b)-restricted molecules and the presented antigen is generated through proteasomal degradation and vacuolar processing. In addition, Salmonella-infected B cells express co-stimulatory molecules such as CD40, CD80, and CD86 as well as inhibitory molecules such as PD-L1. Thus, the cross-presentation of Salmonella antigens and the expression of activation molecules suggest that infected B cells are able to prime and activate specific CD8(+) T cells. However, the Salmonella infection-stimulated expression of PD-L1 suggests that the PD-1/PD-L1 pathway may be involved in turning off the cytotoxic effector response during Salmonella persistent infection, thereby allowing B cells to become a reservoir for the bacteria.

  14. BTK Signaling in B Cell Differentiation and Autoimmunity.

    Science.gov (United States)

    Corneth, Odilia B J; Klein Wolterink, Roel G J; Hendriks, Rudi W

    2016-01-01

    Since the original identification of Bruton's tyrosine kinase (BTK) as the gene defective in the primary immunodeficiency X-linked agammaglobulinemia (XLA) in 1993, our knowledge on the physiological function of BTK has expanded impressively. In this review, we focus on the role of BTK during B cell differentiation in vivo, both in the regulation of expansion and in the developmental progression of pre-B cells in the bone marrow and as a crucial signal transducer of signals downstream of the IgM or IgG B cell antigen receptor (BCR) in mature B cells governing proliferation, survival, and differentiation. In particular, we highlight BTK function in B cells in the context of host defense and autoimmunity. Small-molecule inhibitors of BTK have very recently shown impressive anti-tumor activity in clinical studies in patients with various B cell malignancies. Since promising effects of BTK inhibition were also seen in experimental animal models for lupus and rheumatoid arthritis, BTK may be a good target for controlling autoreactive B cells in patients with systemic autoimmune disease.

  15. Benchmarking for Best Practice

    CERN Document Server

    Zairi, Mohamed

    1998-01-01

    Benchmarking for Best Practice uses up-to-the-minute case-studies of individual companies and industry-wide quality schemes to show how and why implementation has succeeded. For any practitioner wanting to establish best practice in a wide variety of business areas, this book makes essential reading. .It is also an ideal textbook on the applications of TQM since it describes concepts, covers definitions and illustrates the applications with first-hand examples. Professor Mohamed Zairi is an international expert and leading figure in the field of benchmarking. His pioneering work in this area l

  16. HCV 抗原表位预测%Prediction of HCV antigenic epitopes

    Institute of Scientific and Technical Information of China (English)

    贾帅争; 孙红琰; 王全立

    2001-01-01

    应用网络生物信息资源查找丙型肝炎病毒基因组全序列,用软件Lasergene中的EditSeq将来自中国河北株mRNA序列翻译为氨基酸序列,尔后用程序Protean进行氨基酸序列分析,对HCV各区段的B细胞抗原指数进行预测。同时又在两个网站对中国汉族人中频率较高的HLA基因型进行CD8和CD4 T细胞表位预测。B细胞和T细胞抗原表位预测结果对于HCV诊断试剂和疫苗研制有重要的指导意义。%The complete genome of Hepatitis C China virus was gotten from world wide web site NCBI (National Center for Biotechnology Information). HCV mRNA was translated into amino acids(AA) sequence by program EditSeq of a computer software Lasergene and this amino acids sequence was analysed by program Protean. B cell epitopes index of these HCV AA fragments was caculated by this computational program and those epitopes with high index can be used as candidate epitopes for HCV antibody diagnositic reagent. CD8 T cell and CD4 T cell epitopes were predicted at Internet sites (SYFPEITHI and BIMAS). Because those HLA which appear with higher frequence in Chinese Nationalities were chosen to predict T cell epitopes, these predicted sequences can be used to design anti HCV vaccine suitable for Chinese.

  17. Human Memory B Cells in Healthy Gingiva, Gingivitis, and Periodontitis.

    Science.gov (United States)

    Mahanonda, Rangsini; Champaiboon, Chantrakorn; Subbalekha, Keskanya; Sa-Ard-Iam, Noppadol; Rattanathammatada, Warattaya; Thawanaphong, Saranya; Rerkyen, Pimprapa; Yoshimura, Fuminobu; Nagano, Keiji; Lang, Niklaus P; Pichyangkul, Sathit

    2016-08-01

    The presence of inflammatory infiltrates with B cells, specifically plasma cells, is the hallmark of periodontitis lesions. The composition of these infiltrates in various stages of homeostasis and disease development is not well documented. Human tissue biopsies from sites with gingival health (n = 29), gingivitis (n = 8), and periodontitis (n = 21) as well as gingival tissue after treated periodontitis (n = 6) were obtained and analyzed for their composition of B cell subsets. Ag specificity, Ig secretion, and expression of receptor activator of NF-κB ligand and granzyme B were performed. Although most of the B cell subsets in healthy gingiva and gingivitis tissues were CD19(+)CD27(+)CD38(-) memory B cells, the major B cell component in periodontitis was CD19(+)CD27(+)CD38(+)CD138(+)HLA-DR(low) plasma cells, not plasmablasts. Plasma cell aggregates were observed at the base of the periodontal pocket and scattered throughout the gingiva, especially apically toward the advancing front of the lesion. High expression of CXCL12, a proliferation-inducing ligand, B cell-activating factor, IL-10, IL-6, and IL-21 molecules involved in local B cell responses was detected in both gingivitis and periodontitis tissues. Periodontitis tissue plasma cells mainly secreted IgG specific to periodontal pathogens and also expressed receptor activator of NF-κB ligand, a bone resorption cytokine. Memory B cells resided in the connective tissue subjacent to the junctional epithelium in healthy gingiva. This suggested a role of memory B cells in maintaining periodontal homeostasis. PMID:27335500

  18. Epitope discovery with phylogenetic hidden Markov models.

    LENUS (Irish Health Repository)

    Lacerda, Miguel

    2010-05-01

    Existing methods for the prediction of immunologically active T-cell epitopes are based on the amino acid sequence or structure of pathogen proteins. Additional information regarding the locations of epitopes may be acquired by considering the evolution of viruses in hosts with different immune backgrounds. In particular, immune-dependent evolutionary patterns at sites within or near T-cell epitopes can be used to enhance epitope identification. We have developed a mutation-selection model of T-cell epitope evolution that allows the human leukocyte antigen (HLA) genotype of the host to influence the evolutionary process. This is one of the first examples of the incorporation of environmental parameters into a phylogenetic model and has many other potential applications where the selection pressures exerted on an organism can be related directly to environmental factors. We combine this novel evolutionary model with a hidden Markov model to identify contiguous amino acid positions that appear to evolve under immune pressure in the presence of specific host immune alleles and that therefore represent potential epitopes. This phylogenetic hidden Markov model provides a rigorous probabilistic framework that can be combined with sequence or structural information to improve epitope prediction. As a demonstration, we apply the model to a data set of HIV-1 protein-coding sequences and host HLA genotypes.

  19. Theoretical analysis of the neuraminidase epitope of the Mexican A H1N1 influenza strain, and experimental studies on its interaction with rabbit and human hosts.

    Science.gov (United States)

    Loyola, Paola Kinara Reyes; Campos-Rodríguez, R; Bello, Martiniano; Rojas-Hernández, S; Zimic, Mirko; Quiliano, Miguel; Briz, Verónica; Muñoz-Fernández, M Angeles; Tolentino-López, Luis; Correa-Basurto, Jose

    2013-05-01

    The neuraminidase (NA) epitope from the Mexican AH1N1 influenza virus was identified by using sequences registered at the GenBank during the peak of a pandemic (from April 2009 to October 2010). First, NA protein sequences were submitted for multiple alignment analysis, and their three-dimensional models (3-D) were then built by using homology modeling. The most common sequence (denominated wild-type) and its mutants were submitted to linear and nonlinear epitope predictors, which included the major histocompatibility complex type II (MHC II) and B-cell peptides. The epitope prediction was in accordance with evolutionary behavior and some protein structural properties. The latter included a low NA mutation rate, NA 3-D surface exposure, and the presence of high hindrance side chain residues. After selecting the epitope, docking studies and molecular dynamics (MD) simulations were used to explore interactions between the epitope and MHC II. Afterward, several experimental assays were performed to validate the theoretical study by using antibodies from humans (infected by pandemic H1N1) and rabbits (epitope vaccination). The results show 119 complete sequences that were grouped into 28 protein sequences according to their identity (one wild-type and 27 representative mutants (1-5 mutations)). The predictors yielded several epitopes, with the best fit being the one located in the C-terminal region. Theoretical methods demonstrated that the selected epitope reached the P4, P6, P7, and P9 pockets of MHC II, whereas the experimental evidence indicates that the epitope is recognized by human antibodies and also by rabbit antibodies immunized with the peptide.

  20. Hepatitis B synthetic immunogen comprised of nucleocapsid T-cell sites and an envelope B-cell epitope.

    OpenAIRE

    Milich, D R; Hughes, J L; A. McLachlan; Thornton, G B; Moriarty, A.

    1988-01-01

    Previous studies located T-cell recognition of the nucleocapsid of the hepatitis B virus (HBcAg) to residues 120-140 in mice bearing the H-2s or H-2b haplotypes. Herein, we demonstrate that B10.S (H-2s) and B10 (H-2b) H-2 congenic strains recognize distinct T-cell sites within the p120-140 (a synthetic peptide corresponding to residues 120-140 of HBcAg) sequence defined by p120-131 and p129-140, respectively. Peptide p120-131 stimulates B10.S HBcAg-primed T cells, and reciprocally p120-131-pr...

  1. Human pregnancy-associated malaria-specific B cells target polymorphic, conformational epitopes in VAR2CSA

    DEFF Research Database (Denmark)

    Barfod, L.; Bernasconi, N. L.; Dahlback, M.;

    2007-01-01

    Pregnancy-associated malaria (PAM) is caused by Plasmodium falciparum-infected erythrocytes (IEs) that bind to chondroitin sulphate A (CSA) in the placenta by PAM-associated clonally variant surface antigens (VSA). Pregnancy-specific VSA (VSA(PAM)), which include the PfEMP1 variant VAR2CSA, are t...

  2. Dominant B-cell epitopes from cancer/stem cell antigen SOX2 recognized by serum samples from cancer patients

    OpenAIRE

    Shih, Julia; Rahman, Munira; Luong, Quang T; Lomeli, Shirley H.; Riss, Joseph; Prins, Robert M.; Gure, Ali O.; Zeng, Gang

    2014-01-01

    Human sex determining region Y-box 2 (SOX2) is an important transcriptional factor involved in the pluripotency and stemness of human embryonic stem cells. SOX2 plays important roles in maintaining cancer stem cell activities of melanoma and cancers of the brain, prostate, breast, and lung. SOX2 is also a lineage survival oncogene for squamous cell carcinoma of the lung and esophagus. Spontaneous cellular and humoral immune responses against SOX2 present in cancer patients classify it as a tu...

  3. The Immune Epitope Database 2.0

    DEFF Research Database (Denmark)

    Hoof, Ilka; Vita, R; Zarebski, L;

    2010-01-01

    of 4 years, the data from 180,978 experiments were curated manually from the literature, which covers approximately 99% of all publicly available information on peptide epitopes mapped in infectious agents (excluding HIV) and 93% of those mapped in allergens. In addition, data that would otherwise...... be unavailable to the public from 129,186 experiments were submitted directly by investigators. The curation of epitopes related to autoimmunity is expected to be completed by the end of 2010. The database can be queried by epitope structure, source organism, MHC restriction, assay type or host organism, among...

  4. B cell development in the bone marrow is regulated by homeostatic feedback exerted by mature B cells

    Directory of Open Access Journals (Sweden)

    Gitit eShahaf

    2016-03-01

    Full Text Available Cellular homeostasis in the B cell compartment is strictly imposed to balance cell production and cell loss. However, it is not clear whether B cell development in the bone marrow (BM is an autonomous process or subjected to regulation by the peripheral B cell compartment. To specifically address this question, we used mice transgenic for human CD20, where effective depletion of B lineage cells is obtained upon administration of mouse-anti-human CD20 antibodies, in the absence of any effect on other cell lineages and/or tissues. We followed the kinetics of B cell return to equilibrium by BrdU labeling and flow cytometry and analyzed the resulting data by mathematical modeling. Labeling was much faster in depleted mice. Compared to control mice, B cell-depleted mice exhibited a higher proliferation rate in the pro-/pre-B compartment, and higher cell death and lower differentiation in the immature B cell compartment. We validated the first result by analysis of the expression of Ki67, the nuclear protein expressed in proliferating cells, and the second using Annexin-V staining. Collectively, our results suggest that B lymphopoiesis is subjected to homeostatic feedback mechanisms imposed by mature B cells in the peripheral compartment.

  5. HIV-dependent depletion of influenza-specific memory B cells impacts B cell responsiveness to seasonal influenza immunisation

    Science.gov (United States)

    Wheatley, Adam K.; Kristensen, Anne B.; Lay, William N.; Kent, Stephen J.

    2016-01-01

    Infection with HIV drives significant alterations in B cell phenotype and function that can markedly influence antibody responses to immunisation. Anti-retroviral therapy (ART) can partially reverse many aspects of B cell dysregulation, however complete normalisation of vaccine responsiveness is not always observed. Here we examine the effects of underlying HIV infection upon humoral immunity to seasonal influenza vaccines. Serological and memory B cell responses were assessed in 26 HIV+ subjects receiving ART and 30 healthy controls immunised with the 2015 Southern Hemisphere trivalent inactivated influenza vaccine (IIV3). Frequencies and phenotypes of influenza hemagglutinin (HA)-specific B cells were assessed by flow cytometry using recombinant HA probes. Serum antibody was measured using hemagglutination inhibition assays. Serological responses to IIV3 were comparable between HIV+ and HIV− subjects. Likewise, the activation and expansion of memory B cell populations specific for vaccine-component influenza strains was observed in both cohorts, however peak frequencies were diminished in HIV+ subjects compared to uninfected controls. Lower circulating frequencies of memory B cells recognising vaccine-component and historical influenza strains were observed in HIV+ subjects at baseline, that were generally restored to levels comparable with HIV− controls post-vaccination. HIV infection is therefore associated with depletion of selected HA-specific memory B cell pools. PMID:27220898

  6. Transgelin-2 in B-Cells Controls T-Cell Activation by Stabilizing T Cell - B Cell Conjugates

    Science.gov (United States)

    Chae, Myoung-Won; Kim, Hye-Ran; Kim, Chang-Hyun; Jun, Chang-Duk; Park, Zee-Yong

    2016-01-01

    The immunological synapse (IS), a dynamic and organized junction between T-cells and antigen presenting cells (APCs), is critical for initiating adaptive immunity. The actin cytoskeleton plays a major role in T-cell reorganization during IS formation, and we previously reported that transgelin-2, an actin-binding protein expressed in T-cells, stabilizes cortical F-actin, promoting T-cell activation in response to antigen stimulation. Transgelin-2 is also highly expressed in B-cells, although no specific function has been reported. In this study, we found that deficiency in transgelin-2 (TAGLN2-/-) in B-cells had little effect on B-cell development and activation, as measured by the expression of CD69, MHC class II molecules, and CD80/86. Nevertheless, in B-cells, transgelin-2 accumulated in the IS during the interaction with T-cells. These results led us to hypothesize that transgelin-2 may also be involved in IS stability in B-cells, thereby influencing T-cell function. Notably, we found that transgelin-2 deficiency in B-cells reduced T-cell activation, as determined by the release of IL-2 and interferon-γ and the expression of CD69. Furthermore, the reduced T-cell activation was correlated with reduced B-cell–T-cell conjugate formation. Collectively, these results suggest that actin stability in B-cells during IS formation is critical for the initiation of adaptive T-cell immunity. PMID:27232882

  7. Benchmarking Danish Industries

    DEFF Research Database (Denmark)

    Gammelgaard, Britta; Bentzen, Eric; Aagaard Andreassen, Mette

    2003-01-01

    compatible survey. The International Manufacturing Strategy Survey (IMSS) doesbring up the question of supply chain management, but unfortunately, we did not have access to thedatabase. Data from the members of the SCOR-model, in the form of benchmarked performance data,may exist, but are nonetheless...

  8. Benchmark problem proposal

    International Nuclear Information System (INIS)

    The meeting of the Radiation Energy Spectra Unfolding Workshop organized by the Radiation Shielding Information Center is discussed. The plans of the unfolding code benchmarking effort to establish methods of standardization for both the few channel neutron and many channel gamma-ray and neutron spectroscopy problems are presented

  9. Benchmarks: WICHE Region 2012

    Science.gov (United States)

    Western Interstate Commission for Higher Education, 2013

    2013-01-01

    Benchmarks: WICHE Region 2012 presents information on the West's progress in improving access to, success in, and financing of higher education. The information is updated annually to monitor change over time and encourage its use as a tool for informed discussion in policy and education communities. To establish a general context for the…

  10. Surveys and Benchmarks

    Science.gov (United States)

    Bers, Trudy

    2012-01-01

    Surveys and benchmarks continue to grow in importance for community colleges in response to several factors. One is the press for accountability, that is, for colleges to report the outcomes of their programs and services to demonstrate their quality and prudent use of resources, primarily to external constituents and governing boards at the state…

  11. Benchmarking and Performance Management

    Directory of Open Access Journals (Sweden)

    Adrian TANTAU

    2010-12-01

    Full Text Available The relevance of the chosen topic is explained by the meaning of the firm efficiency concept - the firm efficiency means the revealed performance (how well the firm performs in the actual market environment given the basic characteristics of the firms and their markets that are expected to drive their profitability (firm size, market power etc.. This complex and relative performance could be due to such things as product innovation, management quality, work organization, some other factors can be a cause even if they are not directly observed by the researcher. The critical need for the management individuals/group to continuously improve their firm/company’s efficiency and effectiveness, the need for the managers to know which are the success factors and the competitiveness determinants determine consequently, what performance measures are most critical in determining their firm’s overall success. Benchmarking, when done properly, can accurately identify both successful companies and the underlying reasons for their success. Innovation and benchmarking firm level performance are critical interdependent activities. Firm level variables, used to infer performance, are often interdependent due to operational reasons. Hence, the managers need to take the dependencies among these variables into account when forecasting and benchmarking performance. This paper studies firm level performance using financial ratio and other type of profitability measures. It uses econometric models to describe and then propose a method to forecast and benchmark performance.

  12. Benchmarking Public Procurement 2016

    OpenAIRE

    World Bank Group

    2015-01-01

    Benchmarking Public Procurement 2016 Report aims to develop actionable indicators which will help countries identify and monitor policies and regulations that impact how private sector companies do business with the government. The project builds on the Doing Business methodology and was initiated at the request of the G20 Anti-Corruption Working Group.

  13. B-cell survival factors in autoimmune rheumatic disorders

    Science.gov (United States)

    Morais, Sandra A.; Vilas-Boas, Andreia

    2015-01-01

    Autoimmune rheumatic disorders have complex etiopathogenetic mechanisms in which B cells play a central role. The importance of factors stimulating B cells, notably the B-cell activating factor (BAFF) and A proliferation inducing ligand (APRIL) axis is now recognized. BAFF and APRIL are cytokines essential for B-cell proliferation and survival from the immature stages to the development of plasma cells. Their levels are increased in some subsets of patients with autoimmune disorders. Several recent biologic drugs have been developed to block this axis, namely belimumab [already licensed for systemic lupus erythematosus (SLE) treatment], tabalumab, atacicept and blisibimod. Many clinical trials to evaluate the safety and efficacy of these drugs in several autoimmune disorders are ongoing, or have been completed recently. This review updates the information on the use of biologic agents blocking BAFF/APRIL for patients with SLE, rheumatoid arthritis, Sjögren’s syndrome and myositis. PMID:26288664

  14. B-Cell waste classification sampling and analysis plan

    Energy Technology Data Exchange (ETDEWEB)

    HOBART, R.L.

    1999-09-22

    This report documents the methods used to collect and analyze samples to obtain data necessary to verify and/or determine the radionuclide content of the 324 Facility B-Cell decontamination and decommissioning waste stream.

  15. The Use of the Immune Epitope Database to Study Autoimmune Epitope Data Related to Alopecia Areata.

    Science.gov (United States)

    Sette, Alessandro; Paul, Sinu; Vaughan, Kerrie; Peters, Bjoern

    2015-11-01

    The Immune Epitope Database (IEDB) is a repository of published epitope data for infectious diseases, allergy, transplantation and autoimmunity. Herein we provide an introduction to the IEDB search interface, focusing on data related to autoimmune diseases, including alopecia areata (AA). We demonstrate how common questions related can be answered, such as how to search for specific autoantigens, epitope sequences, response types (B- and/or T-cell assays), or host, as well as how to search for epitopes of known major histocompatibility complex restriction and for data related to a specific disease. Our survey of the data found that while as a whole Autoimmunity-specific records represent a significant portion (∼30%); epitopes reported for AA are remarkably few, just 23 epitopes from six antigens. This reveals a significant knowledge gap for AA, and suggests that additional mapping of epitopes and identification of novel AA-associated autoantigens is warranted. Citing recently published examples, we show how bioinformatic, proteomic, and technological advances make it now increasingly feasible to identify epitopes and novel antigens in human disease. The goal herein was to increase awareness of the IEDB as a free resource for the scientific community and to demonstrate its use in finding (existing) and analyzing (prediction) epitope data. PMID:26551944

  16. Interleukin 2-induced proliferation of leukemic human B cells

    OpenAIRE

    1985-01-01

    The proliferative responses of purified leukemic human B cells from nine B cell chronic lymphocytic leukemias to recombinant interleukin 2 (IL-2), spontaneously, and after preactivation by Staphylococcus aureus Cowan I (SAC) or anti-mu antibodies were studied. Three patterns of response were observed: (a) no response (three cases); (b) a moderate spontaneous response enhanced by anti-mu (one case); (c) a high proliferative response after preactivation by anti-mu and/or SAC (five cases). IL-2 ...

  17. Origin of B-Cell Neoplasms in Autoimmune Disease.

    Directory of Open Access Journals (Sweden)

    Kari Hemminki

    Full Text Available Autoimmune diseases (ADs are associated with a number of B-cell neoplasms but the associations are selective in regard to the type of neoplasm and the conferred risks are variable. So far no mechanistic bases for these differential associations have been demonstrated. We speculate that developmental origin of B-cells might propose a mechanistic rationale for their carcinogenic response to autoimmune stimuli and tested the hypothesis on our previous studies on the risks of B-cell neoplasms after any of 33 ADs. We found that predominantly germinal center (GC-derived B-cells showed multiple associations with ADs: diffuse large B cell lymphoma associated with 15 ADs, follicular lymphoma with 7 ADs and Hodgkin lymphoma with 11 ADs. Notably, these neoplasms shared significant associations with 5 ADs (immune thrombocytopenic purpura, polymyositis/dermatomyositis, rheumatoid arthritis, Sjogren syndrome and systemic lupus erythematosis. By contrast, primarily non-GC neoplasms, acute lymphocytic leukemia, chronic lymphocytic leukemia and myeloma associated with 2 ADs only and mantle cell lymphoma with 1 AD. None of the neoplasms shared associated ADs. These data may suggest that autoimmune stimulation critically interferes with the rapid cell division, somatic hypermutation, class switch recombination and immunological selection of maturing B-cell in the GC and delivers damage contributing to transformation.

  18. B cells mediate chronic allograft rejection independently of antibody production.

    Science.gov (United States)

    Zeng, Qiang; Ng, Yue-Harn; Singh, Tripti; Jiang, Ke; Sheriff, Khaleefathullah A; Ippolito, Renee; Zahalka, Salwa; Li, Qi; Randhawa, Parmjeet; Hoffman, Rosemary A; Ramaswami, Balathiripurasundari; Lund, Frances E; Chalasani, Geetha

    2014-03-01

    Chronic rejection is the primary cause of long-term failure of transplanted organs and is often viewed as an antibody-dependent process. Chronic rejection, however, is also observed in mice and humans with no detectable circulating alloantibodies, suggesting that antibody-independent pathways may also contribute to pathogenesis of transplant rejection. Here, we have provided direct evidence that chronic rejection of vascularized heart allografts occurs in the complete absence of antibodies, but requires the presence of B cells. Mice that were deficient for antibodies but not B cells experienced the same chronic allograft vasculopathy (CAV), which is a pathognomonic feature of chronic rejection, as WT mice; however, mice that were deficient for both B cells and antibodies were protected from CAV. B cells contributed to CAV by supporting splenic lymphoid architecture, T cell cytokine production, and infiltration of T cells into graft vessels. In chimeric mice, in which B cells were present but could not present antigen, both T cell responses and CAV were markedly reduced. These findings establish that chronic rejection can occur in the complete absence of antibodies and that B cells contribute to this process by supporting T cell responses through antigen presentation and maintenance of lymphoid architecture.

  19. Altered B cell receptor signaling in human systemic lupus erythematosus

    Science.gov (United States)

    Jenks, Scott A.; Sanz, Iñaki

    2009-01-01

    Regulation of B cell receptor signaling is essential for the development of specific immunity while retaining tolerance to self. Systemic lupus erythematosus (SLE) is characterized by a loss of B cell tolerance and the production of anti-self antibodies. Accompanying this break down in tolerance are alterations in B cell receptor signal transduction including elevated induced calcium responses and increased protein phosphorylation. Specific pathways that negatively regulate B cell signaling have been shown to be impaired in some SLE patients. These patients have reduced levels of the kinase Lyn in lipid raft microdomains and this reduction is inversely correlated with increased CD45 in lipid rafts. Function and expression of the inhibitory immunoglobulin receptor FcγRIIB is also reduced in Lupus IgM- CD27+ memory cells. Because the relative contribution of different memory and transitional B cell subsets can be abnormal in SLE patients, we believe studies targeted to well defined B cell subsets will be necessary to further our understanding of signaling abnormalities in SLE. Intracellular flow cytometric analysis of signaling is a useful approach to accomplish this goal. PMID:18723129

  20. B cells mediate chronic allograft rejection independently of antibody production.

    Science.gov (United States)

    Zeng, Qiang; Ng, Yue-Harn; Singh, Tripti; Jiang, Ke; Sheriff, Khaleefathullah A; Ippolito, Renee; Zahalka, Salwa; Li, Qi; Randhawa, Parmjeet; Hoffman, Rosemary A; Ramaswami, Balathiripurasundari; Lund, Frances E; Chalasani, Geetha

    2014-03-01

    Chronic rejection is the primary cause of long-term failure of transplanted organs and is often viewed as an antibody-dependent process. Chronic rejection, however, is also observed in mice and humans with no detectable circulating alloantibodies, suggesting that antibody-independent pathways may also contribute to pathogenesis of transplant rejection. Here, we have provided direct evidence that chronic rejection of vascularized heart allografts occurs in the complete absence of antibodies, but requires the presence of B cells. Mice that were deficient for antibodies but not B cells experienced the same chronic allograft vasculopathy (CAV), which is a pathognomonic feature of chronic rejection, as WT mice; however, mice that were deficient for both B cells and antibodies were protected from CAV. B cells contributed to CAV by supporting splenic lymphoid architecture, T cell cytokine production, and infiltration of T cells into graft vessels. In chimeric mice, in which B cells were present but could not present antigen, both T cell responses and CAV were markedly reduced. These findings establish that chronic rejection can occur in the complete absence of antibodies and that B cells contribute to this process by supporting T cell responses through antigen presentation and maintenance of lymphoid architecture. PMID:24509079

  1. Computational prediction and analysis of envelop glycoprotein epitopes of DENV-2 and DENV-3 Pakistani isolates: a first step towards Dengue vaccine development.

    Directory of Open Access Journals (Sweden)

    Hafsa Amat-ur-Rasool

    Full Text Available Dengue fever of tropics is a mosquito transmitted devastating disease caused by dengue virus (DENV. There is no effective vaccine available, so far, against any of its four serotypes (DENV-1, DENV-2, DENV-3, and DENV-4. There is a need for the development of preventive and therapeutic vaccines against DENV to decrease the prevalence of dengue fever, especially in Pakistan. In this research, linear and conformational B-cell epitopes of envelope glycoprotein of DENV-2 and DENV-3 (the most prevalent serotypes in Pakistan were predicted. We used Kolaskar and Tongaonkar method for linear epitope prediction, Emini's method for surface accessibility prediction and Karplus and Schulz's algorithm for flexibility determination. To propose three dimensional epitopes, the E proteins for both serotypes were homology modeled by using Phyre2 V 2.0 server, and ElliPro was used for the prediction of surface epitopes on their globular structure. Total 21 and 19 linear epitopes were predicted for DENV-2 and DENV-3 Pakistani isolates respectively. Whereas, 5 and 4 discontinuous epitopes were proposed for DENV-2 and DENV-3 Pakistani isolates respectively. Moreover, the values of surface accessibility, flexibility and solvent-accessibility can be helpful in analyzing vaccines against DENV-2 and DENV-3. In conclusion, the proposed continuous and discontinuous antigenic peptides can be valuable candidates for diagnostic and therapeutics of DENV.

  2. Benchmarking i den offentlige sektor

    DEFF Research Database (Denmark)

    Bukh, Per Nikolaj; Dietrichson, Lars; Sandalgaard, Niels

    2008-01-01

    I artiklen vil vi kort diskutere behovet for benchmarking i fraværet af traditionelle markedsmekanismer. Herefter vil vi nærmere redegøre for, hvad benchmarking er med udgangspunkt i fire forskellige anvendelser af benchmarking. Regulering af forsyningsvirksomheder vil blive behandlet, hvorefter...

  3. Antigen epitope of Helicobacter pylorivacuolating cytotoxin A

    Institute of Scientific and Technical Information of China (English)

    Xiu-Li Liu; Shu-Qin Li; Chun-Jie Liu; Hao-Xia Tao; Zhao-Shan Zhang

    2004-01-01

    AIM: To construct and select antigen epitopes of vacuolating cytotoxin A (VacA) for nontoxic VacA vaccine against Helicobacter pylori (H pylori) infection.METHODS: Eleven VacA epitopes were predicted according to VacA antigenic bioinformatics. Three candidates of VacA epitope were constructed through different combined epitopes. The candidate was linked with E. coli heat-labile enterotoxin B (LTB) by a linker of 7 amino acids, and cloned into plasmid pQE-60 in which fusion LTB-VacA epitope was efficiently expressed. To test the antigencity of the candidate, 6 BALB/c mice were treated with the fusion LTB-VacA epitope through intraperitoneal injection. To explore the ability of inhibiting the toxicity of VacA, cantiserum against the candidate was used to counteract VacA that induced HeLa cells to produce cell vacuoles in vitro.RESULTS: Serum IgG against the candidate was induced in the BALB/c mice. In vitro, the three antisera against the candidate efficiently counteracted the toxicity of VacA, and decreased the number of cell vacuoles by 14.17%, 20.20%and 30.41% respectively.CONCLUSION: Two of the three candidates, LZ-VacA1and LZ-VacA2, can be used to further study the mechanism of vacuolating toxicity of VacA, and to construct nontoxic VacA vaccine against H pylori infection.

  4. Different sensitivity of germinal center B cell-like diffuse large B cell lymphoma cells towards ibrutinib treatment

    OpenAIRE

    Zheng, Xiaohui; Ding, Ning; Song, Yuqin; Feng, Lixia; Zhu, Jun

    2014-01-01

    Background Although rituximab in the combination of CHOP chemotherapy has been widely used as the standard treatment for several kinds of B-cell non-Hodgkin lymphoma (B-NHL), a great number of B-NHL patients treated with this immunotherapy still develop primary and secondary resistance. Recently Bruton’s tyrosine kinase (Btk) inhibitor ibrutinib showed promising therapeutic effect in relapsed/refractory CLL and B-cell NHL, which provided essential alternatives for these patients. Methods The ...

  5. Scope for using plant viruses to present epitopes from animal pathogens.

    Science.gov (United States)

    Porta; Lomonossoff

    1998-01-01

    Epitope presentation to the immune system for vaccination purposes can be achieved either via an inactivated or attenuated form of a pathogen or via its isolated antigenic sequences. When free, these peptides can adopt a variety of conformations, most of which will not exist in their native environment. Conjugation to carrier proteins restricts mobility of the peptides and increases their immunogenicity. A high local concentration of epitopes boosts the immune response further and can be generated by the use of self-aggregating carriers, such as the capsid proteins of viruses. In this regard plant viruses have in recent years started to make an impact as safer alternatives to the use of bacterial and attenuated animal viruses: the latter both require propagation in costly cell-culture systems where they can undergo reversion towards a virulent form and/or become contaminated by other pathogens. Plant virus-based vectors can be multiplied cheaply and to high yields (exceeding 1 mg/g plant tissue) in host plants. Both helical (tobacco mosaic virus, potato virus X, alfalfa mosaic virus) and icosahedral (cowpea mosaic virus, tomato bushy stunt virus) particles have been used to express a number of animal B-cell epitopes, whose immunogenic properties have been explored to varying degrees. Copyright 1998 John Wiley & Sons, Ltd. PMID:10398492

  6. De Novo Transcriptome Analysis of Allium cepa L. (Onion Bulb to Identify Allergens and Epitopes.

    Directory of Open Access Journals (Sweden)

    Hemalatha Rajkumar

    Full Text Available Allium cepa (onion is a diploid plant with one of the largest nuclear genomes among all diploids. Onion is an example of an under-researched crop which has a complex heterozygous genome. There are no allergenic proteins and genomic data available for onions. This study was conducted to establish a transcriptome catalogue of onion bulb that will enable us to study onion related genes involved in medicinal use and allergies. Transcriptome dataset generated from onion bulb using the Illumina HiSeq 2000 technology showed a total of 99,074,309 high quality raw reads (~20 Gb. Based on sequence homology onion genes were categorized into 49 different functional groups. Most of the genes however, were classified under 'unknown' in all three gene ontology categories. Of the categorized genes, 61.2% showed metabolic functions followed by cellular components such as binding, cellular processes; catalytic activity and cell part. With BLASTx top hit analysis, a total of 2,511 homologous allergenic sequences were found, which had 37-100% similarity with 46 different types of allergens existing in the database. From the 46 contigs or allergens, 521 B-cell linear epitopes were identified using BepiPred linear epitope prediction tool. This is the first comprehensive insight into the transcriptome of onion bulb tissue using the NGS technology, which can be used to map IgE epitopes and prediction of structures and functions of various proteins.

  7. Epitope peptides of influenza H3N2 virus neuraminidase gene designed by immunoinformatics

    Institute of Scientific and Technical Information of China (English)

    Lijun Liang; Ping Huang; Miaoheng Wen; Hanzhong Ni; Songnuan Tan; Yonghui Zhang; Qiuxia Chen

    2012-01-01

    The virus surface protein neuraminidase (NA) is a main subtype-specific antigen in influenza type A viruses.Neuraminidase functions as an enzyme to break the bonds between hemagglutinin (HA) and sialic acid to release newly formed viruses from infected cells.In this study,NA genes from the H3N2 subtype virus were sequenced and NA proteins were screened for B-cell epitopes and assessed based on immunoinformatics.Based on this information,three peptides ES8,RR9,and WK7 (covering amino acid residues 221-228,292-300,and 383-389,respectively) of the NA protein were selected and synthesized artificially.These peptides were used to immunize New Zealand rabbits subcutaneously to raise antisera.Results showed that these three peptides were capable of eliciting antibodies against H3N2 viruses in a specific and sensitive manner,detected in vitro by enzyme-linked immunosorbent assay. Furthermore,hemadsorption anti-releasing effects occurred in three antisera mixtures at a dilution of 1∶40.Alignment using database software showed that amino acid residues in these three epitope peptides were substituted at specific sites in all the NAs sequenced in this study.We suggest that these NA epitope peptides might be used in conjunction with HA proteins as vaccine antigens.

  8. The B-cell receptor orchestrates environment-mediated lymphoma survival and drug resistance in B-cell malignancies.

    Science.gov (United States)

    Shain, K H; Tao, J

    2014-08-01

    Specific niches within the lymphoma tumor microenvironment (TME) provide sanctuary for subpopulations of tumor cells through stromal cell-tumor cell interactions. These interactions notably dictate growth, response to therapy and resistance of residual malignant B cells to therapeutic agents. This minimal residual disease (MRD) remains a major challenge in the treatment of B-cell malignancies and contributes to subsequent disease relapse. B-cell receptor (BCR) signaling has emerged as essential mediator of B-cell homing, survival and environment-mediated drug resistance (EMDR). Central to EMDR are chemokine- and integrin-mediated interactions between lymphoma and the TME. Further, stromal cell-B cell adhesion confers a sustained BCR signaling leading to chemokine and integrin activation. Recently, the inhibitors of BCR signaling have garnered a substantial clinical interest because of their effectiveness in B-cell disorders. The efficacy of these agents is, at least in part, attributed to attenuation of BCR-dependent lymphoma-TME interactions. In this review, we discuss the pivotal role of BCR signaling in the integration of intrinsic and extrinsic determinants of TME-mediated lymphoma survival and drug resistance. PMID:24037527

  9. Radiography benchmark 2014

    Science.gov (United States)

    Jaenisch, G.-R.; Deresch, A.; Bellon, C.; Schumm, A.; Lucet-Sanchez, F.; Guerin, P.

    2015-03-01

    The purpose of the 2014 WFNDEC RT benchmark study was to compare predictions of various models of radiographic techniques, in particular those that predict the contribution of scattered radiation. All calculations were carried out for homogenous materials and a mono-energetic X-ray point source in the energy range between 100 keV and 10 MeV. The calculations were to include the best physics approach available considering electron binding effects. Secondary effects like X-ray fluorescence and bremsstrahlung production were to be taken into account if possible. The problem to be considered had two parts. Part I examined the spectrum and the spatial distribution of radiation behind a single iron plate. Part II considered two equally sized plates, made of iron and aluminum respectively, only evaluating the spatial distribution. Here we present the results of above benchmark study, comparing them to MCNP as the assumed reference model. The possible origins of the observed deviations are discussed.

  10. The COST Benchmark

    DEFF Research Database (Denmark)

    Jensen, Christian Søndergaard; Tiesyte, Dalia; Tradisauskas, Nerius

    2006-01-01

    An infrastructure is emerging that enables the positioning of populations of on-line, mobile service users. In step with this, research in the management of moving objects has attracted substantial attention. In particular, quite a few proposals now exist for the indexing of moving objects, and m...... of the benchmark to three spatio-temporal indexes - the TPR-, TPR*-, and Bx-trees. Representative experimental results and consequent guidelines for the usage of these indexes are reported....

  11. Safety and Tolerability Study of PCI-32765 in B Cell Lymphoma and Chronic Lymphocytic Leukemia

    Science.gov (United States)

    2016-04-26

    B-cell Chronic Lymphocytic Leukemia; Small Lymphocytic Lymphoma; Diffuse Well-differentiated Lymphocytic Lymphoma; B Cell Lymphoma; Follicular Lymphoma,; Mantle Cell Lymphoma; Non-Hodgkin's Lymphoma; Waldenstrom Macroglobulinemia; Burkitt Lymphoma; B-Cell Diffuse Lymphoma

  12. Stereotyped patterns of B-cell receptor in splenic marginal zone lymphoma

    KAUST Repository

    Zibellini, S.

    2010-05-29

    Antigen stimulation may be important for splenic marginal zone lymphoma pathogenesis. To address this hypothesis, the occurrence of stereotyped B-cell receptors was investigated in 133 SMZL (26 HCV+) compared with 4,414 HCDR3 sequences from public databases. Sixteen SMZL (12%) showed stereotyped BCR; 7 of 86 (8%) SMZL sequences retrieved from public databases also belonged to stereotyped HCDR3 subsets. Three categories of subsets were identified: i) SMZL-specific subsets (n=5), composed only of 12 SMZL (9 HCV- from our series); ii) Non-Hodgkin\\'s lymphoma-like subsets (n=5), comprising 5 SMZL (4 from our series) clustering with other indolent lymphomas; iii) "CLL-like subsets" (n=6), comprising 6 SMZL (3 from our series) that belonged to known CLL subsets (n=4) or clustered with public CLL sequences. Immunoglobulin 3D modeling of 3 subsets revealed similarities in antigen binding regions not limited to HCDR3. Overall, data suggest that the pathogenesis of splenic marginal zone lymphoma may involve also HCV unrelated epitopes or an antigenic trigger common to other indolent lymphomas. ©2010 Ferrata Storti Foundation.

  13. Antigen presenting B cells facilitate CD4 T cell cooperation resulting in enhanced generation of effector and memory CD4 T cells.

    Directory of Open Access Journals (Sweden)

    David R Kroeger

    Full Text Available We show that the in vivo generation of cytokine-producing CD4 T cells specific for a given major histocompatibility class-II (MHCII-binding peptide of hen egg lysozyme (HEL is facilitated when mice are immunized with splenic antigen presenting cells (APC pulsed with this HEL peptide and another peptide that binds a different MHCII molecule. This enhanced generation of peptide-specific effector CD4 T cells requires that the same splenic APC be pulsed with both peptides. Pulsed B cells, but not pulsed dendritic cells (DCs, can mediate CD4 T cell cooperation, which can be blocked by disrupting OX40-OX40L (CD134-CD252 interactions. In addition, the generation of HEL peptide-specific CD4 T cell memory is greater when mice are primed with B cells pulsed with the two peptides than with B cells pulsed with the HEL- peptide alone. Based on our findings, we suggest CD4 T cell cooperation is important for vaccine design, underlies the phenomenon of "epitope-spreading" seen in autoimmunity, and that the efficacy of B cell-depletion in the treatment of human cell-mediated autoimmune disease is due to the abrogation of the interactions between autoimmune CD4 T cells that facilitates their activation.

  14. T-cell epitope vaccine design by immunoinformatics.

    Science.gov (United States)

    Patronov, Atanas; Doytchinova, Irini

    2013-01-08

    Vaccination is generally considered to be the most effective method of preventing infectious diseases. All vaccinations work by presenting a foreign antigen to the immune system in order to evoke an immune response. The active agent of a vaccine may be intact but inactivated ('attenuated') forms of the causative pathogens (bacteria or viruses), or purified components of the pathogen that have been found to be highly immunogenic. The increased understanding of antigen recognition at molecular level has resulted in the development of rationally designed peptide vaccines. The concept of peptide vaccines is based on identification and chemical synthesis of B-cell and T-cell epitopes which are immunodominant and can induce specific immune responses. The accelerating growth of bioinformatics techniques and applications along with the substantial amount of experimental data has given rise to a new field, called immunoinformatics. Immunoinformatics is a branch of bioinformatics dealing with in silico analysis and modelling of immunological data and problems. Different sequence- and structure-based immunoinformatics methods are reviewed in the paper.

  15. Comprehensive mapping of common immunodominant epitopes in the West Nile virus nonstructural protein 1 recognized by avian antibody responses.

    Directory of Open Access Journals (Sweden)

    Encheng Sun

    Full Text Available West Nile virus (WNV is a mosquito-borne flavivirus that primarily infects birds but occasionally infects humans and horses. Certain species of birds, including crows, house sparrows, geese, blue jays and ravens, are considered highly susceptible hosts to WNV. The nonstructural protein 1 (NS1 of WNV can elicit protective immune responses, including NS1-reactive antibodies, during infection of animals. The antigenicity of NS1 suggests that NS1-reactive antibodies could provide a basis for serological diagnostic reagents. To further define serological reagents for diagnostic use, the antigenic sites in NS1 that are targeted by host immune responses need to be identified and the potential diagnostic value of individual antigenic sites also needs to be defined. The present study describes comprehensive mapping of common immunodominant linear B-cell epitopes in the WNV NS1 using avian WNV NS1 antisera. We screened antisera from chickens, ducks and geese immunized with purified NS1 for reactivity against 35 partially overlapping peptides covering the entire WNV NS1. This study identified twelve, nine and six peptide epitopes recognized by chicken, duck and goose antibody responses, respectively. Three epitopes (NS1-3, 14 and 24 were recognized by antibodies elicited by immunization in all three avian species tested. We also found that NS1-3 and 24 were WNV-specific epitopes, whereas the NS1-14 epitope was conserved among the Japanese encephalitis virus (JEV serocomplex viruses based on the reactivity of avian WNV NS1 antisera against polypeptides derived from the NS1 sequences of viruses of the JEV serocomplex. Further analysis showed that the three common polypeptide epitopes were not recognized by antibodies in Avian Influenza Virus (AIV, Newcastle Disease Virus (NDV, Duck Plague Virus (DPV and Goose Parvovirus (GPV antisera. The knowledge and reagents generated in this study have potential applications in differential diagnostic approaches and

  16. The NAS Parallel Benchmarks

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, David H.

    2009-11-15

    The NAS Parallel Benchmarks (NPB) are a suite of parallel computer performance benchmarks. They were originally developed at the NASA Ames Research Center in 1991 to assess high-end parallel supercomputers. Although they are no longer used as widely as they once were for comparing high-end system performance, they continue to be studied and analyzed a great deal in the high-performance computing community. The acronym 'NAS' originally stood for the Numerical Aeronautical Simulation Program at NASA Ames. The name of this organization was subsequently changed to the Numerical Aerospace Simulation Program, and more recently to the NASA Advanced Supercomputing Center, although the acronym remains 'NAS.' The developers of the original NPB suite were David H. Bailey, Eric Barszcz, John Barton, David Browning, Russell Carter, LeoDagum, Rod Fatoohi, Samuel Fineberg, Paul Frederickson, Thomas Lasinski, Rob Schreiber, Horst Simon, V. Venkatakrishnan and Sisira Weeratunga. The original NAS Parallel Benchmarks consisted of eight individual benchmark problems, each of which focused on some aspect of scientific computing. The principal focus was in computational aerophysics, although most of these benchmarks have much broader relevance, since in a much larger sense they are typical of many real-world scientific computing applications. The NPB suite grew out of the need for a more rational procedure to select new supercomputers for acquisition by NASA. The emergence of commercially available highly parallel computer systems in the late 1980s offered an attractive alternative to parallel vector supercomputers that had been the mainstay of high-end scientific computing. However, the introduction of highly parallel systems was accompanied by a regrettable level of hype, not only on the part of the commercial vendors but even, in some cases, by scientists using the systems. As a result, it was difficult to discern whether the new systems offered any fundamental

  17. PD-L1 expression in B-cell lymphomas and virus-associated malignancies--letter

    DEFF Research Database (Denmark)

    Andersen, Mads Hald

    2013-01-01

    actually trigger their own inhibition by secreting cytokines that drive tumor PD-L1 expression (3). However, the immune system itself seems also to have established a respective counteractive mechanism, that is, PD-L1–specific, CD8+, cytotoxic T cells. Thus, PD-L1–reactive T cells can readily be isolated...... processed and thus derived PD-L1 epitopes. PD-L1 antibodies target surface protein, whereas PD-L1–specific T cells recognize and kill cells, which are expressing PD-L1 epitopes on the surface derived from intracellular PD-L1. It is important to note that PD-L1 additionally is expressed on normal immune......In a very important recent study, Chen and colleagues describe that PD-L1 (B7-H1, CD274) is expressed on both malignant cells and infiltrating macrophages in a subset of aggressive B-cell lymphomas (1). The article highlights the possibilities of targeting the PD-1/PD-L1 pathway in these...

  18. Th1 and Th2 help for B cells

    DEFF Research Database (Denmark)

    Poudrier, J; Owens, T

    1995-01-01

    Sustained interaction with Th1 cells has been shown to induce IL-2 responsiveness by murine B cells. This is equivalently dependent on CD40, CD54/ICAM-1 and MHC II ligation, and co-cross-linking of CD54 and MHC II in the presence of IL-5 up-regulates a functional IL-2R on B cells. We now show...... that IL-5 (125 U/ml) synergizes with Th1 cells to induce B cell responses to IL-2, that are maintained following T-cell removal, e.g. autonomous. Th1 help in the absence of IL-5 resulted in weak or undetectable responses following T cell removal. The mechanism of IL-5 synergy involved persistence of IL-2R...... beta expression following T cell removal, as opposed to enhancement of IL-2R induction or function. The level of contact-induced IL-2R expression on B cells was not itself modified by IL-5. The effects of IL-5 did not overcome the requirement for T contact signals and treatment of B cells with soluble...

  19. Chimeric peptide containing both B and T cells epitope of tumor-associated antigen L6 enhances anti-tumor effects in HLA-A2 transgenic mice.

    Science.gov (United States)

    Lin, Su-I; Huang, Ming-Hsi; Chang, Yu-Wen; Chen, I-Hua; Roffler, Steve; Chen, Bing-Mae; Sher, Yuh-Pyng; Liu, Shih-Jen

    2016-07-28

    Synthetic peptides are attractive for cancer immunotherapy because of their safety and flexibility. In this report, we identified a new B cell epitope of tumor-associated antigen L6 (TAL6) that could induce antibody-dependent cellular cytotoxicity (ADCC) in vivo. We incorporated the B cell epitope with a cytotoxic T lymphocyte (CTL) and a helper T (Th) epitope to form a chimeric long peptide. We formulated the chimeric peptide with different adjuvants to immunize HLA-A2 transgenic mice and evaluate their immunogenicity. The chimeric peptide formulated with an emulsion type nanoparticle (PELC) adjuvant and a toll-like receptor 9 agonist (CpG ODN) (PELC/CpG) induced the greatest ADCC and CTL responses. The induced anti-tumor immunity inhibited the growth of TAL6-positive cancer cells. Moreover, we observed that immunization with the chimeric peptide inhibited cancer cell migration in vitro and metastasis in vivo. These data suggest that a chimeric peptide containing both B and T cell epitopes of TAL6 formulated with PELC/CpG adjuvant is feasible for cancer immunotherapy. PMID:27130449

  20. CD4 T cell epitope specificity determines follicular versus non-follicular helper differentiation in the polyclonal response to influenza infection or vaccination

    Science.gov (United States)

    Knowlden, Zackery A. G.; Sant, Andrea J.

    2016-01-01

    Follicular helper T cells (Tfh) are essential for B cell production of high-affinity, class-switched antibodies. Much interest in Tfh development focuses on the priming environment of CD4 T cells. Here we explored the role that peptide specificity plays in the partitioning of the polyclonal CD4 T cell repertoire between Tfh and NonTfh lineages during the response to influenza. Surprisingly, we found that CD4 T cells specific for different epitopes exhibited distinct tendencies to segregate into Tfh or NonTfh. To alter the microenvironment and abundance, viral antigens were introduced as purified recombinant proteins in adjuvant as native proteins. Also, the most prototypical epitopes were expressed in a completely foreign protein. In many cases, the epitope-specific response patterns of Tfh vs. NonTfh persisted. The functional TcR avidity of only a subset of epitope-specific cells correlated with the tendency to drive a Tfh response. Thus, we conclude that in a polyclonal CD4 T cell repertoire, features of TcR-peptide:MHC class II complex have a strong deterministic influence on the ability of CD4 T cells to become a Tfh or a NonTfh. Our data is most consistent with at least 2 checkpoints of Tfh selection that include both TcR affinity and B cell presentation. PMID:27329272

  1. CD4 T cell epitope specificity determines follicular versus non-follicular helper differentiation in the polyclonal response to influenza infection or vaccination.

    Science.gov (United States)

    Knowlden, Zackery A G; Sant, Andrea J

    2016-01-01

    Follicular helper T cells (Tfh) are essential for B cell production of high-affinity, class-switched antibodies. Much interest in Tfh development focuses on the priming environment of CD4 T cells. Here we explored the role that peptide specificity plays in the partitioning of the polyclonal CD4 T cell repertoire between Tfh and NonTfh lineages during the response to influenza. Surprisingly, we found that CD4 T cells specific for different epitopes exhibited distinct tendencies to segregate into Tfh or NonTfh. To alter the microenvironment and abundance, viral antigens were introduced as purified recombinant proteins in adjuvant as native proteins. Also, the most prototypical epitopes were expressed in a completely foreign protein. In many cases, the epitope-specific response patterns of Tfh vs. NonTfh persisted. The functional TcR avidity of only a subset of epitope-specific cells correlated with the tendency to drive a Tfh response. Thus, we conclude that in a polyclonal CD4 T cell repertoire, features of TcR-peptide:MHC class II complex have a strong deterministic influence on the ability of CD4 T cells to become a Tfh or a NonTfh. Our data is most consistent with at least 2 checkpoints of Tfh selection that include both TcR affinity and B cell presentation. PMID:27329272

  2. Microenvironment-Centred Dynamics in Aggressive B-Cell Lymphomas

    Directory of Open Access Journals (Sweden)

    Matilde Cacciatore

    2012-01-01

    Full Text Available Aggressive B-cell lymphomas share high proliferative and invasive attitudes and dismal prognosis despite heterogeneous biological features. In the interchained sequence of events leading to cancer progression, neoplastic clone-intrinsic molecular events play a major role. Nevertheless, microenvironment-related cues have progressively come into focus as true determinants for this process. The cancer-associated microenvironment is a complex network of nonneoplastic immune and stromal cells embedded in extracellular components, giving rise to a multifarious crosstalk with neoplastic cells towards the induction of a supportive milieu. The immunological and stromal microenvironments have been classically regarded as essential partners of indolent lymphomas, while considered mainly negligible in the setting of aggressive B-cell lymphomas that, by their nature, are less reliant on external stimuli. By this paper we try to delineate the cardinal microenvironment-centred dynamics exerting an influence over lymphoid clone progression in aggressive B-cell lymphomas.

  3. The role of B cells and autoantibodies in neuropsychiatric lupus.

    Science.gov (United States)

    Wen, Jing; Stock, Ariel D; Chalmers, Samantha A; Putterman, Chaim

    2016-09-01

    The central nervous system manifestations of SLE (neuropsychiatric lupus, NPSLE) occur frequently, though are often difficult to diagnose and treat. Symptoms of NPSLE can be quite diverse, including chronic cognitive and emotional manifestations, as well as acute presentations, such as stroke and seizures. Although the pathogenesis of NPSLE has yet to be well characterized, B-cell mediated damage is believed to be an important contributor. B-cells and autoantibodies may traverse the blood brain barrier promoting an inflammatory environment consisting of glia activation, neurodegeneration, and consequent averse behavioral outcomes. This review will evaluate the various suggested roles of B-cells and autoantibodies in NPSLE, as well as therapeutic modalities targeting these pathogenic mediators.

  4. Novel Therapies for Aggressive B-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Kenneth A. Foon

    2012-01-01

    Full Text Available Aggressive B-cell lymphoma (BCL comprises a heterogeneous group of malignancies, including diffuse large B-cell lymphoma (DLBCL, Burkitt lymphoma, and mantle cell lymphoma (MCL. DLBCL, with its 3 subtypes, is the most common type of lymphoma. Advances in chemoimmunotherapy have substantially improved disease control. However, depending on the subtype, patients with DLBCL still exhibit substantially different survival rates. In MCL, a mature B-cell lymphoma, the addition of rituximab to conventional chemotherapy regimens has increased response rates, but not survival. Burkitt lymphoma, the most aggressive BCL, is characterized by a high proliferative index and requires more intensive chemotherapy regimens than DLBCL. Hence, there is a need for more effective therapies for all three diseases. Increased understanding of the molecular features of aggressive BCL has led to the development of a range of novel therapies, many of which target the tumor in a tailored manner and are summarized in this paper.

  5. Dataset of transcriptional landscape of B cell early activation

    Directory of Open Access Journals (Sweden)

    Alexander S. Garruss

    2015-09-01

    Full Text Available Signaling via B cell receptors (BCR and Toll-like receptors (TLRs result in activation of B cells with distinct physiological outcomes, but transcriptional regulatory mechanisms that drive activation and distinguish these pathways remain unknown. At early time points after BCR and TLR ligand exposure, 0.5 and 2 h, RNA-seq was performed allowing observations on rapid transcriptional changes. At 2 h, ChIP-seq was performed to allow observations on important regulatory mechanisms potentially driving transcriptional change. The dataset includes RNA-seq, ChIP-seq of control (Input, RNA Pol II, H3K4me3, H3K27me3, and a separate RNA-seq for miRNA expression, which can be found at Gene Expression Omnibus Dataset GSE61608. Here, we provide details on the experimental and analysis methods used to obtain and analyze this dataset and to examine the transcriptional landscape of B cell early activation.

  6. Identification of three new type-specific antigen epitopes in the capsid protein of porcine circovirus type 1.

    Science.gov (United States)

    Huang, Liping; Lu, Yuehua; Wei, Yanwu; Guo, Longjun; Liu, Changming

    2012-07-01

    Porcine circovirus type 1 (PCV1) has been identified as a contaminant of porcine kidney cell line (PK-15). Serological evidence and genetic studies have suggested that PCV1 is widespread in domestic pigs. In this study, monoclonal antibodies (mAbs) and polyclonal antibodies (pAbs) were generated against a recombinant PCV1 Cap protein (PCV1-Cap), which was expressed using the baculovirus system. PEPSCAN analysis was used to identify epitopes on the PCV1-Cap with mAbs and pAbs. Three linear B-cell epitopes, including residues (85)GGTNPLP(91), (162)FTPKPELDKTIDWFHPNNK(180) and (219)YVQFREFILKDPLNK(233), specific for PCV1-Cap, were finely defined. These results will facilitate future investigations into antigenic differences and differential diagnosis between PCV1 and PCV2. PMID:22437253

  7. T-24.B-cell differentiation factor induces immunoglobulin secretion in human B cells without prior cell replication.

    Science.gov (United States)

    Gallagher, G; Christie, J F; Stimson, W H; Guy, K; Dewar, A E

    1987-04-01

    Stimulation of B lymphocytes from B-cell chronic lymphocytic leukaemia (B-CLL) with 12-0-tetradecanoylphorbol-13-acetate (TPA) has shown that these cells are capable of differentiation (Totterman, Nilsson & Sundstrom, 1980). Increases in the expression of different class II MHC antigens (Guy et al., 1983, 1986) and responsiveness to growth factors (Kabelitz et al., 1985; Suzuki, Butler & Cooper, 1985) have been studied. Supernatant from the human bladder carcinoma line T-24 contains a B-cell differentiation factor (BCDF) able to induce immunoglobulin secretion from CESS cells. We investigated the induction of proliferation and immunoglobulin secretion in human B cells by studying the effects of this factor on B-CLL cells, in both the presence and absence of TPA. We report here that this material (termed T-24.BCDF) causes immunoglobulin secretion to be initiated in these cells, and that this is not accompanied by detectable DNA synthesis. These observations were extended to normal human B cells and demonstrate that human B cells can secrete immunoglobulin in the absence of clonal expansion. PMID:3495482

  8. Experimental validation of multi-epitope peptides including promising MHC class I- and class II-restricted epitopes of four known Leishmania infantum proteins

    Directory of Open Access Journals (Sweden)

    Maria eAgallou

    2014-06-01

    Full Text Available Leishmaniasis is a significant worldwide health problem for which no vaccine exists. Activation of CD4+ and CD8+ T cells is crucial for the generation of protective immunity against parasite. Recent trend in vaccine design has been shifted to epitope-based vaccines that are more specific, safe, and easy to produce. In the present study, four known antigenic Leishmania (L. infantum proteins, CPA, histone H1, KMP-11 and LeIF were analysed for the prediction of binding epitopes to H2d MHC class I and class II molecules, using online available algorithms. Based on in silico analysis, eight peptides including highly scored MHC class I- and class II-restricted epitopes were synthesized. Peptide immunogenicity was validated in MHC compatible BALB/c mice immunized with each synthetic peptide emulsified in CFA/IFA. CPA_p2, CPA_p3, H1_p1 and LeIF_p6 induced strong spleen cell proliferation upon in vitro peptide re-stimulation. In addition, the majority of the peptides, except of LeIF_p1 and KMP-11_p1, induced IFN-γ secretion, while KMP-11_p1 indicated a suppressive effect on IL-10 production. CPA_p2, CPA_p3, LeIF_p3 and LeIF_p6 induced IFN-γ-producing CD4+ T cells indicating a TH1 type response. In addition, CPA_p2, CPA_p3 and H1_p1 induced also the induction of CD8+ T cells. The induction of peptide-specific IgG in immunized mice designated also the existence of B cell epitopes in peptide sequences. Combining immunoinformatic tools and experimental validation, we demonstrated that CPA_p2, CPA_p3, H1_p1, H1_p3, CPA_p2, LeIF_p3 and LeIF_p6 are likely to include potential epitopes for the induction of protective cytotoxic and/or TH1-type immune responses supporting the feasibility of peptide-based vaccine development for leishmaniasis.

  9. Regulation of AID, the B-cell genome mutator.

    Science.gov (United States)

    Keim, Celia; Kazadi, David; Rothschild, Gerson; Basu, Uttiya

    2013-01-01

    The mechanisms by which B cells somatically engineer their genomes to generate the vast diversity of antibodies required to challenge the nearly infinite number of antigens that immune systems encounter are of tremendous clinical and academic interest. The DNA cytidine deaminase activation-induced deaminase (AID) catalyzes two of these mechanisms: class switch recombination (CSR) and somatic hypermutation (SHM). Recent discoveries indicate a significant promiscuous targeting of this B-cell mutator enzyme genome-wide. Here we discuss the various regulatory elements that control AID activity and prevent AID from inducing genomic instability and thereby initiating oncogenesis.

  10. 2001 benchmarking guide.

    Science.gov (United States)

    Hoppszallern, S

    2001-01-01

    Our fifth annual guide to benchmarking under managed care presents data that is a study in market dynamics and adaptation. New this year are financial indicators on HMOs exiting the market and those remaining. Hospital financial ratios and details on department performance are included. The physician group practice numbers show why physicians are scrutinizing capitated payments. Overall, hospitals in markets with high managed care penetration are more successful in managing labor costs and show productivity gains in imaging services, physical therapy and materials management.

  11. Design and prediction of multi-epitope gene of influenza A virus%流感病毒多表位基因盒的设计与预测

    Institute of Scientific and Technical Information of China (English)

    邵京京; 丰锋; 张强; 李虹; 李明远; 王保宁; 李婉宜

    2012-01-01

    目的 预测流感病毒抗原表位并设计合成多表位基因盒.方法 收集不同类型流感病毒基因序列,联合运用Syf-peithi、ProPred、Muhipred2、Bcepred、Clastal X1.83、SWISS - MODEL等多种生物信息学软件进行分析,预测流感病毒Matrix1(M1)、Matrix2( M2)、Nucleoprotein (NP)和HA蛋白上的抗原表位,设计并合成流感病毒多表位基因盒.结果 在不同亚型流感病毒的HA蛋白抗原上成功筛选出2个B细胞表位,在M1、M2及NP蛋白上分别筛选出3个T细胞表位,以一定的间隔序列串联各表位,设计并合成流感多表位基因盒.预测结果显示该多表位基因盒具有良好的同源性及抗原性.结论 成功设计出包含T细胞表位及B细胞表位的流感病毒多表位基因盒Eg,为流感多表位基因疫苗的研发奠定了基础.%OBJECTIVE To design and predict multi - epitope gene of influenza A virus. METHODS Different gene sequences of current popular influenza A virus were searched. The epitopes on Matrixlprotein ( Ml ) , Matrix2 protein ( M2) , Nucleoprotein ( NP) and Hemagglutinin (HA) were analyzed and screened using bioinformatics programs such as Syfpeithi, ProPred, Multipred2, Bcepred, Clastal XI. 83 and SWISS - MODEL. The multi - epitope gene of influenza A virus was designed and synthesized by series connection. RESULTS Two B cell epitopes on HA and three T cell epitopes on Ml ,M2 or NP were screened and multi - epitope gene of influenza A virus was designed successfully. Prediction of epitope showed that the multi - epitope gene had better homology and antigenicity, and could keep better biologicalactivity after incised by protease. CONCLUSION The Multi - epitope gene combined with T cell epitopes and B cell epitopes, has been successfully prepared and lays the foundation for further study on the multi -epitope gene vaccine against influenza A virus.

  12. Surrogate light chain is required for central and peripheral B-cell tolerance and inhibits anti-DNA antibody production by marginal zone B cells.

    Science.gov (United States)

    Ren, Weicheng; Grimsholm, Ola; Bernardi, Angelina I; Höök, Nina; Stern, Anna; Cavallini, Nicola; Mårtensson, Inga-Lill

    2015-04-01

    Selection of the primary antibody repertoire takes place in pro-/pre-B cells, and subsequently in immature and transitional B cells. At the first checkpoint, μ heavy (μH) chains assemble with surrogate light (SL) chain into a precursor B-cell receptor. In mice lacking SL chain, μH chain selection is impaired, and serum autoantibody levels are elevated. However, whether the development of autoantibody-producing cells is due to an inability of the resultant B-cell receptors to induce central and/or peripheral B-cell tolerance or other factors is unknown. Here, we show that receptor editing is defective, and that a higher proportion of BM immature B cells are prone to undergoing apoptosis. Furthermore, transitional B cells are also more prone to undergoing apoptosis, with a stronger selection pressure to enter the follicular B-cell pool. Those that enter the marginal zone (MZ) B-cell pool escape selection and survive, possibly due to the B-lymphopenia and elevated levels of B-cell activating factor. Moreover, the MZ B cells are responsible for the elevated IgM anti-dsDNA antibody levels detected in these mice. Thus, the SL chain is required for central and peripheral B-cell tolerance and inhibits anti-DNA antibody production by MZ B cells.

  13. Primary B-cell deficiencies reveal a link between human IL-17-producing CD4 T-cell homeostasis and B-cell differentiation.

    Directory of Open Access Journals (Sweden)

    Rita R Barbosa

    Full Text Available IL-17 is a pro-inflammatory cytokine implicated in autoimmune and inflammatory conditions. The development/survival of IL-17-producing CD4 T cells (Th17 share critical cues with B-cell differentiation and the circulating follicular T helper subset was recently shown to be enriched in Th17 cells able to help B-cell differentiation. We investigated a putative link between Th17-cell homeostasis and B cells by studying the Th17-cell compartment in primary B-cell immunodeficiencies. Common Variable Immunodeficiency Disorders (CVID, defined by defects in B-cell differentiation into plasma and memory B cells, are frequently associated with autoimmune and inflammatory manifestations but we found no relationship between these and Th17-cell frequency. In fact, CVID patients showed a decrease in Th17-cell frequency in parallel with the expansion of activated non-differentiated B cells (CD21(lowCD38(low. Moreover, Congenital Agammaglobulinemia patients, lacking B cells due to impaired early B-cell development, had a severe reduction of circulating Th17 cells. Finally, we found a direct correlation in healthy individuals between circulating Th17-cell frequency and both switched-memory B cells and serum BAFF levels, a crucial cytokine for B-cell survival. Overall, our data support a relationship between Th17-cell homeostasis and B-cell maturation, with implications for the understanding of the pathogenesis of inflammatory/autoimmune diseases and the physiology of B-cell depleting therapies.

  14. Benchmarking concentrating photovoltaic systems

    Science.gov (United States)

    Duerr, Fabian; Muthirayan, Buvaneshwari; Meuret, Youri; Thienpont, Hugo

    2010-08-01

    Integral to photovoltaics is the need to provide improved economic viability. To achieve this goal, photovoltaic technology has to be able to harness more light at less cost. A large variety of concentrating photovoltaic concepts has provided cause for pursuit. To obtain a detailed profitability analysis, a flexible evaluation is crucial for benchmarking the cost-performance of this variety of concentrating photovoltaic concepts. To save time and capital, a way to estimate the cost-performance of a complete solar energy system is to use computer aided modeling. In this work a benchmark tool is introduced based on a modular programming concept. The overall implementation is done in MATLAB whereas Advanced Systems Analysis Program (ASAP) is used for ray tracing calculations. This allows for a flexible and extendable structuring of all important modules, namely an advanced source modeling including time and local dependence, and an advanced optical system analysis of various optical designs to obtain an evaluation of the figure of merit. An important figure of merit: the energy yield for a given photovoltaic system at a geographical position over a specific period, can be calculated.

  15. HPC Benchmark Suite NMx Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Intelligent Automation Inc., (IAI) and University of Central Florida (UCF) propose to develop a comprehensive numerical test suite for benchmarking current and...

  16. Immunomodulatory effect of Mesenchymal Stem Cells on B cells

    Directory of Open Access Journals (Sweden)

    Marcella eFranquesa

    2012-07-01

    Full Text Available The research on T cell immunosuppression therapies has attracted most of the attention in clinical transplantation. However, B cells and humoral immune responses are increasingly acknowledged as crucial mediators of chronic allograft rejection. Indeed, humoral immune responses can lead to renal allograft rejection even in patients whose cell-mediated immune responses are well controlled. On the other hand, newly studied B cell subsets with regulatory effects have been linked to tolerance achievement in transplantation. Better understanding of the regulatory and effector B cell responses may therefore lead to new therapeutic approaches.Mesenchymal Stem Cells (MSC are arising as a potent therapeutic tool in transplantation due to their regenerative and immunomodulatory properties. The research on MSCs has mainly focused on their effects on T cells and although data regarding the modulatory effects of MSCs on alloantigen-specific humoral response in humans is scarce, it has been demonstrated that MSCs significantly affect B cell functioning. In the present review we will analyze and discuss the results in this field.

  17. Isolation of human monoclonal antibodies from peripheral blood B cells.

    Science.gov (United States)

    Huang, Jinghe; Doria-Rose, Nicole A; Longo, Nancy S; Laub, Leo; Lin, Chien-Li; Turk, Ellen; Kang, Byong H; Migueles, Stephen A; Bailer, Robert T; Mascola, John R; Connors, Mark

    2013-10-01

    Isolation of monoclonal antibodies is an important technique for understanding the specificities and characteristics of antibodies that underlie the humoral immune response to a given antigen. Here we describe a technique for isolating monoclonal antibodies from human peripheral blood mononuclear cells. The protocol includes strategies for the isolation of switch-memory B cells from peripheral blood, the culture of B cells, the removal of the supernatant for screening and the lysis of B cells in preparation for immunoglobulin heavy-chain and light-chain amplification and cloning. We have observed that the addition of cytokines IL-2, IL-21 and irradiated 3T3-msCD40L feeder cells can successfully stimulate switch-memory B cells to produce high concentrations of IgG in the supernatant. The supernatant may then be screened by appropriate assays for binding or for other functions. This protocol can be completed in 2 weeks. It is adaptable to use in other species and enables the efficient isolation of antibodies with a desired functional characteristic without prior knowledge of specificity. PMID:24030440

  18. Impact of Gastrointestinal Bacillus anthracis Infection on Hepatic B Cells

    Directory of Open Access Journals (Sweden)

    Natacha Colliou

    2015-09-01

    Full Text Available Ingestion of Bacillus anthracis results in rapid gastrointestinal (GI infection, known as GI anthrax. We previously showed that during GI anthrax, there is swift deterioration of intestinal barrier function leading to translocation of gut-associated bacteria into systemic circulation. Additionally, we described dysfunction in colonic B cells. In concordance with our previous studies, here, we report early migration of the Sterne strain of B. anthracis along with other gut-resident bacteria into the infected murine liver. Additionally, despite a global decrease in the B cell population, we observed an increase in both B-1a and marginal zone (MZ-like B cells. Both of these cell types are capable of producing immunoglobulins against common pathogens and commensals, which act as a general antibody barrier before an antigen-specific antibody response. Accumulation of these cells in the liver was associated with an increase in chemokine expression. These data suggest that the presence of Sterne and other commensals in the liver trigger migration of MZ-like B cells from the spleen to the liver to neutralize systemic spread. Further research is required to evaluate the possible cause of their failure to clear the infection within the liver, including the potential role of dysfunctional mitogen-activated protein kinase (MAPK signaling.

  19. Characterization of B cell responses in relation to organ transplantation

    NARCIS (Netherlands)

    Heidt, Sebastiaan

    2010-01-01

    Antibody-mediated rejection is increasingly recognised within the transplantation community as a cause or contributing factor in the rejection of transplanted organs. The humoral immune response towards allografts involves B cells that, after T cell dependent activation, can differentiate into antib

  20. Innate B Cells Tell ILC How It's Done.

    Science.gov (United States)

    Nguyen, Trang T T; Baumgarth, Nicole

    2016-07-19

    Innate lymphoid cells (ILCs) are known as first responders to infections and as instructors of subsequent CD4(+) T cell cytokine profiles. In this issue of Immunity, Fan and colleagues now demonstrate that even earlier responding innate-like B cells (NKB) induce these protective ILC responses. PMID:27438761

  1. Characterization of T cell epitopes in bovine α-lactalbumin

    NARCIS (Netherlands)

    Meulenbroek, Laura A P M; den Hartog Jager, Constance F; Lebens, Ans F M; Knulst, André C; Bruijnzeel-Koomen, Carla A F M; Garssen, Johan; Knippels, Léon M J; van Hoffen, Els

    2014-01-01

    BACKGROUND: Recent studies have indicated that peptides containing T cell epitopes may be used for immunotherapy. While for several cow's milk allergens the T cell epitopes have been described, the T cell epitopes in the major allergen α-lactalbumin (α-LAC) are unknown. Therefore, the aim of this st

  2. Three novel NY-ESO-1 epitopes bound to DRB1*0803, DQB1*0401 and DRB1*0901 recognized by CD4 T cells from CHP-NY-ESO-1-vaccinated patients.

    Science.gov (United States)

    Mizote, Yu; Taniguchi, Taku; Tanaka, Kei; Isobe, Midori; Wada, Hisashi; Saika, Takashi; Kita, Shoichi; Koide, Yukari; Uenaka, Akiko; Nakayama, Eiichi

    2010-07-19

    Three novel NY-ESO-1 CD4 T cell epitopes were identified using PBMC obtained from patients who were vaccinated with a complex of cholesterol-bearing hydrophobized pullulan (CHP) and NY-ESO-1 protein (CHP-NY-ESO-1). The restriction molecules were determined by antibody blocking and using various EBV-B cells with different HLA alleles as APC to present peptides to CD4 T cells. The minimal epitope peptides were determined using various N- and C-termini truncated peptides deduced from 18-mer overlapping peptides originally identified for recognition. Those epitopes were DRB1*0901-restricted NY-ESO-1 87-100, DQB1*0401-restricted NY-ESO-1 95-107 and DRB1*0803-restricted NY-ESO-1 124-134. CD4 T cells used to determine those epitope peptides recognized EBV-B cells or DC that were treated with recombinant NY-ESO-1 protein or NY-ESO-1-expressing tumor cell lysate, suggesting that the epitope peptides are naturally processed. These CD4 T cells showed a cytokine profile with Th1 characteristics. Furthermore, NY-ESO-1 87-100 peptide/HLA-DRB1*0901 tetramer staining was observed. Multiple Th1-type CD4 T cell responses are beneficial for inducing effective anti-tumor responses after NY-ESO-1 protein vaccination.

  3. B cell autophagy mediates TLR7-dependent autoimmunity and inflammation.

    Science.gov (United States)

    Weindel, Chi G; Richey, Lauren J; Bolland, Silvia; Mehta, Abhiruchi J; Kearney, John F; Huber, Brigitte T

    2015-01-01

    Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease, defined by loss of B cell self-tolerance that results in production of antinuclear antibodies (ANA) and chronic inflammation. While the initiating events in lupus development are not well defined, overexpression of the RNA-recognizing toll-like receptor (TLR)7 has been linked to SLE in humans and mice. We postulated that autophagy plays an essential role in TLR7 activation of B cells for the induction of SLE by delivering RNA ligands to the endosomes, where this innate immune receptor resides. To test this hypothesis, we compared SLE development in Tlr7 transgenic (Tg) mice with or without B cell-specific ablation of autophagy (Cd19-Cre Atg5(f/f)). We observed that in the absence of B cell autophagy the 2 hallmarks of SLE, ANA and inflammation, were eliminated, thus curing these mice of lupus. This was also evident in the significantly extended survival of the autophagy-deficient mice compared to Tlr7.1 Tg mice. Furthermore, glomerulonephritis was ameliorated, and the serum levels of inflammatory cytokines in the knockout (KO) mice were indistinguishable from those of control mice. These data provide direct evidence that B cells require TLR7-dependent priming through an autophagy-dependent mechanism before autoimmunity is induced, thereafter involving many cell types. Surprisingly, hyper-IgM production persisted in Tlr7.1 Tg mice in the absence of autophagy, likely involving a different activation pathway than the production of autoantibodies. Furthermore, these mice still presented with anemia, but responded with a striking increase in extramedullary hematopoiesis (EMH), possibly due to the absence of pro-inflammatory cytokines.

  4. Germinal center B cells recognize antigen through a specialized immune synapse architecture.

    Science.gov (United States)

    Nowosad, Carla R; Spillane, Katelyn M; Tolar, Pavel

    2016-07-01

    B cell activation is regulated by B cell antigen receptor (BCR) signaling and antigen internalization in immune synapses. Using large-scale imaging across B cell subsets, we found that, in contrast with naive and memory B cells, which gathered antigen toward the synapse center before internalization, germinal center (GC) B cells extracted antigen by a distinct pathway using small peripheral clusters. Both naive and GC B cell synapses required proximal BCR signaling, but GC cells signaled less through the protein kinase C-β-NF-κB pathway and produced stronger tugging forces on the BCR, thereby more stringently regulating antigen binding. Consequently, GC B cells extracted antigen with better affinity discrimination than naive B cells, suggesting that specialized biomechanical patterns in B cell synapses regulate T cell-dependent selection of high-affinity B cells in GCs. PMID:27183103

  5. Assessment of CD37 B-cell antigen and cell-of-origin significantly improves risk prediction in diffuse large B-cell lymphoma

    DEFF Research Database (Denmark)

    Xu-Monette, Zijun Y; Li, Ling; Byrd, John C;

    2016-01-01

    CD37 (tetraspanin TSPAN26) is a B-cell surface antigen widely expressed on mature B-cells. CD37 is involved in immune regulation and tumor suppression but its function has not been fully elucidated. In this study, we assessed CD37 expression in de novo diffuse large B-cell lymphoma (DLBCL), and i...

  6. Benchmarking and Regulation

    DEFF Research Database (Denmark)

    Agrell, Per J.; Bogetoft, Peter

    nchmarking methods, and in particular Data Envelopment Analysis (DEA), have become well-established and informative tools for economic regulation. DEA is now routinely used by European regulators to set reasonable revenue caps for energy transmission and distribution system operators. The applica......nchmarking methods, and in particular Data Envelopment Analysis (DEA), have become well-established and informative tools for economic regulation. DEA is now routinely used by European regulators to set reasonable revenue caps for energy transmission and distribution system operators....... The application of benchmarking in regulation, however, requires specific steps in terms of data validation, model specification and outlier detection that are not systematically documented in open publications, leading to discussions about regulatory stability and economic feasibility of these techniques...

  7. Benchmarking foreign electronics technologies

    Energy Technology Data Exchange (ETDEWEB)

    Bostian, C.W.; Hodges, D.A.; Leachman, R.C.; Sheridan, T.B.; Tsang, W.T.; White, R.M.

    1994-12-01

    This report has been drafted in response to a request from the Japanese Technology Evaluation Center`s (JTEC) Panel on Benchmarking Select Technologies. Since April 1991, the Competitive Semiconductor Manufacturing (CSM) Program at the University of California at Berkeley has been engaged in a detailed study of quality, productivity, and competitiveness in semiconductor manufacturing worldwide. The program is a joint activity of the College of Engineering, the Haas School of Business, and the Berkeley Roundtable on the International Economy, under sponsorship of the Alfred P. Sloan Foundation, and with the cooperation of semiconductor producers from Asia, Europe and the United States. Professors David A. Hodges and Robert C. Leachman are the project`s Co-Directors. The present report for JTEC is primarily based on data and analysis drawn from that continuing program. The CSM program is being conducted by faculty, graduate students and research staff from UC Berkeley`s Schools of Engineering and Business, and Department of Economics. Many of the participating firms are represented on the program`s Industry Advisory Board. The Board played an important role in defining the research agenda. A pilot study was conducted in 1991 with the cooperation of three semiconductor plants. The research plan and survey documents were thereby refined. The main phase of the CSM benchmarking study began in mid-1992 and will continue at least through 1997. reports are presented on the manufacture of integrated circuits; data storage; wireless technology; human-machine interfaces; and optoelectronics. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  8. Benchmarking monthly homogenization algorithms

    Directory of Open Access Journals (Sweden)

    V. K. C. Venema

    2011-08-01

    Full Text Available The COST (European Cooperation in Science and Technology Action ES0601: Advances in homogenization methods of climate series: an integrated approach (HOME has executed a blind intercomparison and validation study for monthly homogenization algorithms. Time series of monthly temperature and precipitation were evaluated because of their importance for climate studies and because they represent two important types of statistics (additive and multiplicative. The algorithms were validated against a realistic benchmark dataset. The benchmark contains real inhomogeneous data as well as simulated data with inserted inhomogeneities. Random break-type inhomogeneities were added to the simulated datasets modeled as a Poisson process with normally distributed breakpoint sizes. To approximate real world conditions, breaks were introduced that occur simultaneously in multiple station series within a simulated network of station data. The simulated time series also contained outliers, missing data periods and local station trends. Further, a stochastic nonlinear global (network-wide trend was added.

    Participants provided 25 separate homogenized contributions as part of the blind study as well as 22 additional solutions submitted after the details of the imposed inhomogeneities were revealed. These homogenized datasets were assessed by a number of performance metrics including (i the centered root mean square error relative to the true homogeneous value at various averaging scales, (ii the error in linear trend estimates and (iii traditional contingency skill scores. The metrics were computed both using the individual station series as well as the network average regional series. The performance of the contributions depends significantly on the error metric considered. Contingency scores by themselves are not very informative. Although relative homogenization algorithms typically improve the homogeneity of temperature data, only the best ones improve

  9. SSI and structural benchmarks

    International Nuclear Information System (INIS)

    This paper presents the latest results of the ongoing program entitled, Standard Problems for Structural Computer Codes, currently being worked on at BNL for the USNRC, Office of Nuclear Regulatory Research. During FY 1986, efforts were focussed on three tasks, namely, (1) an investigation of ground water effects on the response of Category I structures, (2) the Soil-Structure Interaction Workshop and (3) studies on structural benchmarks associated with Category I structures. The objective of the studies on ground water effects is to verify the applicability and the limitations of the SSI methods currently used by the industry in performing seismic evaluations of nuclear plants which are located at sites with high water tables. In a previous study by BNL (NUREG/CR-4588), it has been concluded that the pore water can influence significantly the soil-structure interaction process. This result, however, is based on the assumption of fully saturated soil profiles. Consequently, the work was further extended to include cases associated with variable water table depths. In this paper, results related to cut-off depths beyond which the pore water effects can be ignored in seismic calculations, are addressed. Comprehensive numerical data are given for soil configurations typical to those encountered in nuclear plant sites. These data were generated by using a modified version of the SLAM code which is capable of handling problems related to the dynamic response of saturated soils. Further, the paper presents some key aspects of the Soil-Structure Interaction Workshop (NUREG/CP-0054) which was held in Bethesda, MD on June 1, 1986. Finally, recent efforts related to the task on the structural benchmarks are described

  10. Development of an epitope conservancy analysis tool to facilitate the design of epitope-based diagnostics and vaccines

    Directory of Open Access Journals (Sweden)

    Fusseder Nicolas

    2007-09-01

    Full Text Available Abstract Background In an epitope-based vaccine setting, the use of conserved epitopes would be expected to provide broader protection across multiple strains, or even species, than epitopes derived from highly variable genome regions. Conversely, in a diagnostic and disease monitoring setting, epitopes that are specific to a given pathogen strain, for example, can be used to monitor responses to that particular infectious strain. In both cases, concrete information pertaining to the degree of conservancy of the epitope(s considered is crucial. Results To assist in the selection of epitopes with the desired degree of conservation, we have developed a new tool to determine the variability of epitopes within a given set of protein sequences. The tool was implemented as a component of the Immune Epitope Database and Analysis Resources (IEDB, and is directly accessible at http://tools.immuneepitope.org/tools/conservancy. Conclusion An epitope conservancy analysis tool was developed to analyze the variability or conservation of epitopes. The tool is user friendly, and is expected to aid in the design of epitope-based vaccines and diagnostics.

  11. Ibrutinib Before and After Stem Cell Transplant in Treating Patients With Relapsed or Refractory Diffuse Large B-cell Lymphoma

    Science.gov (United States)

    2016-10-20

    Activated B-Cell-Like Diffuse Large B-Cell Lymphoma; B-Cell Lymphoma, Unclassifiable, With Features Intermediate Between Diffuse Large B-Cell Lymphoma and Burkitt Lymphoma; Recurrent Diffuse Large B-Cell Lymphoma; Refractory Diffuse Large B-Cell Lymphoma

  12. Viral O-GalNAc peptide epitopes

    DEFF Research Database (Denmark)

    Olofsson, Sigvard; Blixt, Klas Ola; Bergström, Tomas;

    2016-01-01

    Viral envelope glycoproteins are major targets for antibodies that bind to and inactivate viral particles. The capacity of a viral vaccine to induce virus-neutralizing antibodies is often used as a marker for vaccine efficacy. Yet the number of known neutralization target epitopes is restricted o...

  13. IgE-binding epitopes: a reappraisal

    NARCIS (Netherlands)

    R.C. Aalberse; R. Crameri

    2011-01-01

    Here, we discuss various questions related to IgE epitopes: What are the technical possibilities and pitfalls, what is currently known, how can we put this information into hypothetical frameworks and the unavoidable question: how useful is this information for patient care or allergenicity predicti

  14. Benchmark for Strategic Performance Improvement.

    Science.gov (United States)

    Gohlke, Annette

    1997-01-01

    Explains benchmarking, a total quality management tool used to measure and compare the work processes in a library with those in other libraries to increase library performance. Topics include the main groups of upper management, clients, and staff; critical success factors for each group; and benefits of benchmarking. (Author/LRW)

  15. Benchmark simulation models, quo vadis?

    DEFF Research Database (Denmark)

    Jeppsson, U.; Alex, J; Batstone, D. J.;

    2013-01-01

    As the work of the IWA Task Group on Benchmarking of Control Strategies for wastewater treatment plants (WWTPs) is coming to an end, it is essential to disseminate the knowledge gained. For this reason, all authors of the IWA Scientific and Technical Report on benchmarking have come together to p...

  16. The B cell antigen receptor and overexpression of MYC can cooperate in the genesis of B cell lymphomas.

    Directory of Open Access Journals (Sweden)

    Yosef Refaeli

    2008-06-01

    Full Text Available A variety of circumstantial evidence from humans has implicated the B cell antigen receptor (BCR in the genesis of B cell lymphomas. We generated mouse models designed to test this possibility directly, and we found that both the constitutive and antigen-stimulated state of a clonal BCR affected the rate and outcome of lymphomagenesis initiated by the proto-oncogene MYC. The tumors that arose in the presence of constitutive BCR differed from those initiated by MYC alone and resembled chronic B cell lymphocytic leukemia/lymphoma (B-CLL, whereas those that arose in response to antigen stimulation resembled large B-cell lymphomas, particularly Burkitt lymphoma (BL. We linked the genesis of the BL-like tumors to antigen stimulus in three ways. First, in reconstruction experiments, stimulation of B cells by an autoantigen in the presence of overexpressed MYC gave rise to BL-like tumors that were, in turn, dependent on both MYC and the antigen for survival and proliferation. Second, genetic disruption of the pathway that mediates signaling from the BCR promptly killed cells of the BL-like tumors as well as the tumors resembling B-CLL. And third, growth of the murine BL could be inhibited by any of three distinctive immunosuppressants, in accord with the dependence of the tumors on antigen-induced signaling. Together, our results provide direct evidence that antigenic stimulation can participate in lymphomagenesis, point to a potential role for the constitutive BCR as well, and sustain the view that the constitutive BCR gives rise to signals different from those elicited by antigen. The mouse models described here should be useful in exploring further the pathogenesis of lymphomas, and in preclinical testing of new therapeutics.

  17. Quantum benchmarks for Gaussian states

    CERN Document Server

    Chiribella, Giulio

    2014-01-01

    Teleportation and storage of continuous variable states of light and atoms are essential building blocks for the realization of large scale quantum networks. Rigorous validation of these implementations require identifying, and surpassing, benchmarks set by the most effective strategies attainable without the use of quantum resources. Such benchmarks have been established for special families of input states, like coherent states and particular subclasses of squeezed states. Here we solve the longstanding problem of defining quantum benchmarks for general pure Gaussian states with arbitrary phase, displacement, and squeezing, randomly sampled according to a realistic prior distribution. As a special case, we show that the fidelity benchmark for teleporting squeezed states with totally random phase and squeezing degree is 1/2, equal to the corresponding one for coherent states. We discuss the use of entangled resources to beat the benchmarks in experiments.

  18. Benchmarking & European Sustainable Transport Policies

    DEFF Research Database (Denmark)

    Gudmundsson, H.

    2003-01-01

    , Benchmarking is one of the management tools that have recently been introduced in the transport sector. It is rapidly being applied to a wide range of transport operations, services and policies. This paper is a contribution to the discussion of the role of benchmarking in the future efforts...... to support Sustainable European Transport Policies. The key message is that transport benchmarking has not yet been developed to cope with the challenges of this task. Rather than backing down completely, the paper suggests some critical conditions for applying and adopting benchmarking for this purpose. One...... way forward is to ensure a higher level of environmental integration in transport policy benchmarking. To this effect the paper will discuss the possible role of the socalled Transport and Environment Reporting Mechanism developed by the European Environment Agency. The paper provides an independent...

  19. Expression and immunoreactivity of HCV/HBV epitopes

    Institute of Scientific and Technical Information of China (English)

    Xin-Yu Xiong; Xiao Liu; Yuan-Ding Chen

    2005-01-01

    AIM: To develop the epitope-based vaccines to prevent Hepatitis C virus (HCV)/Hepatitis B virus (HBV) infections.METHODS: The HCV core epitopes C1 STNPKPQRKTKRNTNRRPQD (residuals aa2-21) and C2 VKFPGGGQIVGGVYLLPRR (residuals aa22-40), envelope epitope E GHRMAWDMMMNWSP (residuals aa315-328) and HBsAg epitope S CTTPAQGNSMFPSCCCTKPTDGNC (residuals aa124-147) were displayed in five different sites of the flock house virus capsid protein as a vector, and expressed in E. coli cells (pET-3 system).Immunoreactivity of the epitopes with anti-HCV and anti-HBV antibodies in the serum from hepatitis C and hepatitis B patients were determined.RESULTS: The expressed chimeric protein carrying the HCV epitopes C1, C2, E (two times), L3C1-I2E-L1C2-L2E could react with anti-HCV antibodies. The expressed chimeric protein carrying the HBV epitopes S, I3S could react with anti-HBs antibodies. The expressed chimeric proteins carrying the HCV epitopes C1, C2, E plus HBV epitope S, L3C1-I2E-L1C2-L2E-I3S could react with antiHCV and anti-HBs antibodies.CONCLUSION: These epitopes have highly specific and sensitive immunoreaction and are useful in the development of epitope-based vaccines.

  20. Measles Virus Hemagglutinin Protein Epitopes: The Basis of Antigenic Stability

    Science.gov (United States)

    Tahara, Maino; Bürckert, Jean-Philippe; Kanou, Kazuhiko; Maenaka, Katsumi; Muller, Claude P.; Takeda, Makoto

    2016-01-01

    Globally eliminating measles using available vaccines is biologically feasible because the measles virus (MV) hemagglutinin (H) protein is antigenically stable. The H protein is responsible for receptor binding, and is the main target of neutralizing antibodies. The immunodominant epitope, known as the hemagglutinating and noose epitope, is located near the receptor-binding site (RBS). The RBS also contains an immunodominant epitope. Loss of receptor binding correlates with an escape from the neutralization by antibodies that target the epitope at RBS. Another neutralizing epitope is located near RBS and is shielded by an N-linked sugar in certain genotype strains. However, human sera from vaccinees and measles patients neutralized all MV strains with similar efficiencies, regardless of the N-linked sugar modification or mutations at these epitopes. Two other major epitopes exist at a distance from RBS. One has an unstructured flexible domain with a linear neutralizing epitope. When MV-H forms a tetramer (dimer of dimers), these epitopes may form the dimer-dimer interface, and one of the two epitopes may also interact with the F protein. The neutralization mechanisms of antibodies that recognize these epitopes may involve inhibiting the H-F interaction or blocking the fusion cascade after MV-H binds to its receptors. PMID:27490564

  1. Deletion of genes encoding PU.1 and Spi-B in B cells impairs differentiation and induces pre-B cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Sokalski, Kristen M; Li, Stephen K H; Welch, Ian; Cadieux-Pitre, Heather-Anne T; Gruca, Marek R; DeKoter, Rodney P

    2011-09-01

    The E26 transformation-specific (Ets) transcription factor PU.1 is required to generate lymphoid progenitor cells from hematopoietic stem cells, but it is not required to generate B cells from committed B-cell lineage progenitors. We hypothesized that PU.1 function in B-cell differentiation is complemented by the related Ets transcription factor Spi-B. To test this hypothesis, mice were generated lacking both PU.1 and Spi-B in the B-cell lineage. Unlike mice lacking PU.1 or Spi-B, mice deficient in both PU.1 and Spi-B in the B-cell lineage had reduced frequencies of B cells as well as impaired B-cell differentiation. Strikingly, all PU.1 and Spi-B-deficient mice developed pre-B cell acute lymphoblastic leukemia before 30 weeks of age. Pre-B cells accumulated in the thymus resulting in massive thymic enlargement and dyspnea. These findings demonstrate that PU.1 and Spi-B are essential transcriptional regulators of B-cell differentiation as well as novel tumor suppressors in the B-cell lineage.

  2. Low GILT expression is associated with poor patient survival in diffuse large B-cell lymphoma

    Directory of Open Access Journals (Sweden)

    Hannah ePhipps-Yonas

    2013-12-01

    Full Text Available The MHC class II-restricted antigen processing pathway presents antigenic peptides acquired in the endocytic route for the activation of CD4+ T cells. Multiple cancers express MHC class II, which may influence the anti-tumor immune response and patient outcome. Low MHC class II expression is associated with poor survival in diffuse large B-cell lymphoma (DLBCL, the most common form of aggressive non-Hodgkin lymphoma. Therefore, we investigated whether gamma-interferon-inducible lysosomal thiol reductase (GILT, an upstream component of the MHC class II-restricted antigen processing pathway that is not regulated by the transcription factor class II transactivator, may be important in DLBCL biology. GILT reduces protein disulfide bonds in the endocytic compartment, exposing additional epitopes for MHC class II binding and facilitating antigen presentation. In each of four independent gene expression profiling cohorts with a total of 585 DLBCL patients, low GILT expression was significantly associated with poor overall survival. In contrast, low expression of a classical MHC class II gene, HLA-DRA, was associated with poor survival in one of four cohorts. The association of low GILT expression with poor survival was independent of established clinical and molecular prognostic factors, the International Prognostic Index and the cell of origin classification, respectively. Immunohistochemical analysis of GILT expression in 96 DLBCL cases demonstrated variation in GILT protein expression within tumor cells which correlated strongly with GILT mRNA expression. These studies identify a novel association between GILT expression and clinical outcome in lymphoma. Our findings underscore the role of antigen processing in DLBCL and suggest that molecules targeting this pathway warrant investigation as potential therapeutics.

  3. Cutaneous B cell lymphomas: Report of two interesting cases

    Directory of Open Access Journals (Sweden)

    Ravichandran Gurumurthy

    2015-01-01

    Full Text Available Cutaneous B cell lymphomas can arise primarily from the skin or may occur due to secondary spread from nodal lymphomas. Primary lymphomas are confined to the skin without systemic spread and they differ from secondary lymphomas in their clinical behavior, treatment and prognosis. Cutaneous lymphomas being relatively rare, lack of precise definition and understanding of their clinical behavior diseases leads to pitfalls in the diagnosis. We report two cases of cutaneous B cell lymphomas who presented with fever of unknown origin initially and later found to have skin lesions. Hence, skin can be a potential diagnostic clue in the evaluation of patients with fever of unknown origin. The distinctions between the primary and the secondary lymphomas become important in choosing the treatment and assessing the prognosis.

  4. 324 Facility B-cell quality process plan

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, J.L.

    1998-07-29

    B-Cell is currently being cleaned out (i.e., removal of equipment, fixtures and residual radioactive materials) and deactivated. TPA Milestone M-89-02 dictates that all mixed waste and equipment be removed from B-Cell by 5/31/99. The following sections describe the major activities that remain for completion of the TPA milestone. These include: Size Reduce Tank 119 and Miscellaneous Equipment; Load and Ship Low-Level Waste; Remove and Size Reduce the 1B Rack; Collect Dispersible Material from Cell Floor; Remove and Size Reduce the 2A Rack; Size Reduce the 1A Rack; Load and Ship Mixed Waste to PUREX Tunnels; and Move Spent Fuel to A-Cell;

  5. ANTI-B CELL THERAPY OF AUTOIMMUNE DISEASES

    Directory of Open Access Journals (Sweden)

    A. L. Masliansky

    2007-01-01

    Full Text Available Abstract. Our understanding of the multiple physiological and pathological functions of B-cells continues to expand at a fascinating rate. As pathogenic elements in the development of autoimmune diseases, B-cells have become the focus of new therapeutics. Based on the published data, rituximab, a chimeric monoclonal antibody to CD20, when used in combination with other agents (i.e., cyclophosphamide or methotrexate, appears to be a reasonable treatment option for refractory RA. There are now numerous case reports and small openlabel series using rituximab in many autoimmune diseases, others then RA. While these data must be interpreted with caution, they suggest that rituximab may be a promising addition to the therapeutic armamentarium in these diseases. However, additional controlled trials need to be conducted to confirm clinical efficacy, further define optimal dosage, response rates, comparative long-term efficacy, and treatment algorithm for rituximab in these patients.

  6. Design and evaluation of a multi-epitope assembly Peptide (MEAP against herpes simplex virus type 2 infection in BALB/c mice

    Directory of Open Access Journals (Sweden)

    Pan Mingjie

    2011-05-01

    Full Text Available Abstract Background Human herpes simplex virus (HSV 1 and 2 causes oral, ocular, or genital infections, which remains a significant health problem worldwide. HSV-1 and -2 infections in humans range from localized skin infections of the oral, ocular, and genital regions to severe and often disseminated infections in immunocompromised hosts. Epitope based vaccination is a promising mean to achieve protective immunity and to avoid infections with Human herpes simplex virus type 2 (HSV-2. Methods The twelve selected epitopes, six B cell epitopes from different glycoprotein of HSV-2 (amino acid residues 466-473 (EQDRKPRN from envelope glycoprotein B, 216-223 (GRTDRPSA from C, 6-18 (DPSLKMADPNRFR from D, 483-491 (DPPERPDSP from E, 572-579 (EPPDDDDS from G and 286-295 (CRRRYRRPRG from I glycoprotein of HSV-2, four CD4+ T cell epitopes (amino acid residues 21-28 (NLPVLDQL from D, 162-177 (KDVTVSQVWFGHRYSQ from B, 205-224 (KAYQQGVTVDSIGMLPRFIP from D and 245-259 (KPPYTSTLLPPELSD from D and two CD8+ T cell epitopes (amino acid residues 10-20 (KMADPNRFRGK from D and 268-276 (ALLEDPAGT from D, are responsible for the elicitation of the neutralizing antibodies and cytotoxic T lymphocytes (CTLs that impart protective immunity to the host. In this study, all above epitopes were inserted into the extracellular fragment (amino acid residues 1-290 of HSV-2 glycoprotein D to construct multi-epitope assembly peptides (MEAPs by replacing some non-epitope amino acid sequences. The epitope independency of the MEAPs was predicted by three-dimensional software algorithms. The gene of the selected MEAP was expressed in E.coli BL21(DE3, and its protective efficacy against HSV-2 infection was assessed in BALB/c mice. Results The MEAP, with each inserted epitopes independently displayed on the molecule surface, was selected as candidate proteins. The results showed that the MEAP was highly immunogenic and could elicit high titer neutralizing antibodies and cell

  7. Diffuse Large B Cell Lymphoma of the Breast

    OpenAIRE

    Feryal Karaca; Vehbi Ercolak; Cigdem Usul Afsar; Meral Gunaldi

    2015-01-01

    Primary breast lymphoma is rarely encountered in Non-Hodgkin Lymphomas. However, if early diagnosis is made, and treatment is started immediately in patients with low grade and stage, patient survival is increased. 39-year old female patient applied us due to a palpable mass. She was diagnosed with the Non-Hodgkin Lymphoma Diffuse Large B Cell Lymphoma after the investigations. Curative external radiotherapy was applied after 6 courses of CHOP-R chemotherapy to the patient with Stage-IIE favo...

  8. Sources of DNA for detecting B cell monoclonality using PCR.

    OpenAIRE

    Diss, T. C.; Pan, L.; Peng, H; Wotherspoon, A C; Isaacson, P G

    1994-01-01

    AIMS--To evaluate the polymerase chain reaction (PCR) demonstration of clonal immunoglobulin heavy chain gene rearrangements using routinely prepared, unstained, and stained formalin fixed, paraffin wax embedded tissue samples. METHODS--Extracts from (a) fresh frozen tissue samples, (b) unstained, and (c) haematoxylin and eosin stained formalin fixed, paraffin wax embedded 5 microns tissue sections from 42 cases of low grade B cell lymphoma, all shown to be monoclonal by Southern blot analysi...

  9. [Significance of regulatory B cells in nosogenesis of immune thrombocytopenia].

    Science.gov (United States)

    Li, Xin; Wang, Fang; Ding, Kai Yang; Dai, Lan

    2014-04-01

    This study was aimed to investigate the role of regulatory B cells (Breg) in pathogenesis of immune thrombocytopenia (ITP) and its clinical significance. A total of 35 ITP patients and 20 normal controls were enrolled in this study. The expression of CD19(+)CD24(hi)CD38(hi) B cells was detected by flow cytometry and the expression of IL-10 mRNA and TGF-β1 mRNA was assayed by RT-PCR. The results indicated that the expression level of CD19(+)CD24(hi)CD38(hi) B cells in peripheral blood of newly diagnosed ITP patients was obviously lower than that in normal controls (P < 0.05); the expression level of CD19(+)CD24(hi)CD38(hi) B cells in ITP patients with increased platelet count after treatment was higher than that before treatment (P < 0.05); the expression level of IL-10 mRNA in newly diagnosed ITP patients was significantly lower than that the in normal controls (P < 0.05), the expression level of TGF-β1 mRNA in newly diagnosed ITP patients increases as compared with normal controls (P < 0.05), after treatment with DXM the expression of IL-10 mRNA was enhanced, the expression of TGF-β1 mRNA was reduced as compared with expression level before treatment (P < 0.05). It is concluded that the Breg cells may play an important role in the pathogenesis of ITP via humoral immunity and its regulation of T lymphocytes.

  10. Characterization of Memory B-Cells from Thymus and its Impact for DLBCL Classification

    DEFF Research Database (Denmark)

    Bergkvist, Kim Steve; Nørgaard, Martin Agge; Bøgsted, Martin;

    2016-01-01

    The rare memory B-cells in thymus are considered the cell of origin for primary mediastinal large B-cell lymphoma (PMBL). The goals for the present study were to characterize the normal memory B-cell compartment in thymus and support its association to primary mediastinal B-cell lymphoma. Seven...... paired human tissue samples from thymus and sternum bone marrow were harvested during cardiac surgery. B-cell subsets were phenotyped by Euroflow standard and FACS-sorted for microarray analysis on the Human Exon 1.0 ST Arrays platform. Differentially expressed genes between thymus and bone marrow memory...... B-cells were identified and correlated to the molecular subclasses of diffuse large B-cell lymphoma. Within thymus, 4% (median, range 2-14%) of the CD45(+) haematopoietic cells were CD19(+) B-cells with a major fraction being CD27(+)/CD38(-) memory B-cells (median 80%, range 76-93%). The bone marrow...

  11. Targeting B cell responses in universal influenza vaccine design

    Science.gov (United States)

    Kaur, Kaval; Sullivan, Meghan; Wilson, Patrick C

    2011-01-01

    Since its first administration in the 1940s, the influenza vaccine has provided tremendous relief against influenza infections. However, time has revealed the vaccine’s ultimate limit and the call for its reinvention has now come, just as we are beginning to appreciate the antibody immune responses vital in preventing infections. New strategies to design the influenza vaccine rely on selectively inducing broadly neutralizing antibodies that are specific for highly conserved viral epitopes. Such approaches take us away from the limited range of protection provided by current seasonal influenza vaccines and towards a future with a pan-influenza vaccine capable of providing universal strain coverage. PMID:21940217

  12. Antigen Processing by Autoreactive B Cells Promotes Determinant Spreading

    Institute of Scientific and Technical Information of China (English)

    Yang D.Dai; George Carayanniotis; Eli Sercarz

    2005-01-01

    Acute primary immune responses tend to focus on few immunodominant determinants using a very limited number of T cell clones for expansion, whereas chronic inflammatory responses generally recruit a large number of different T cell clones to attack a broader range of determinants of the invading pathogens or the inflamed tissues.In T cell-mediated organ-specific autoimmune disease, a transition from the acute to the chronic phase contributes to pathogenesis, and the broadening process is called determinant spreading. The cellular components catalyzing the spreading reaction are not identified. It has been suggested that autoreactive B cells may play a central role in diversifying autoreactive T cell responses, possibly through affecting antigen processing and presentation. The clonal identity and diversity of the B cells and antibodies seem critical in regulating T cell activity and subsequent tissue damage or repair. Here, we use two autoimmune animal models, experimental autoimmune thyroiditis (EAT)and type 1 diabetes (T1D), to discuss how autoreactive B cells or antibodies alter the processing and presentation of autoantigens to regulate specific T cell response.

  13. The acquisition of cytokine responsiveness by murine B cells

    DEFF Research Database (Denmark)

    Poudrier, J; Owens, T

    1994-01-01

    The mechanism whereby small resting (high buoyant density) murine B cells are induced to express interleukin-2 receptors (IL-2R) and to respond to IL-2 was addressed by staining with anti-IL-2R alpha and -IL-2R beta monoclonal antibodies (mAb), and using receptor-specific cDNA probes. Resting B...... staining and mRNA were induced by the combination of LPS plus IL-5. LPS+IL-5-treated B cells responded to IL-2 by Ig secretion. This indicates that B cells regulate their responsiveness to IL-2 similarly to T cells, via the combined level of expression of IL-2R beta and IL-2R alpha. The synergy between IL...... cells expressed undetectable levels of both IL-2R alpha and beta chains on their surface and did not respond to IL-2, even at supra-physiological concentrations. Sepharose-coupled, but not streptavidin-cross-linked, plastic-adsorbed or soluble, anti-mu up-regulated the expression of IL-2R alpha and beta...

  14. Lenalidomide in Diffuse Large B-Cell Lymphomas

    Directory of Open Access Journals (Sweden)

    Annalisa Chiappella

    2012-01-01

    Full Text Available Diffuse Large B-cell Lymphomas (DLBCL are the most frequent Non-Hodgkin Lymphomas (NHL. The addition of Rituximab to the standard chemotherapy CHOP improved the outcome in this patients, but so far 40% of patients experienced relapse or progressive disease. Lenalidomide, an immunomodulatory agent, had direct tumoricidal and antiangiogenetic actions on tumor cells and was able to modulate tumor-cell microenvironment, with the restoration of impaired T-cell activity and the formation of immuno-synapsis. Based on these actions, lenalidomide represented an active drug on aggressive relapsed NHL. In this review, the most relevant clinical trials for the use of lenalidomide in DLBCL were reported. Monotherapy with lenalidomide showed an activity in term of overall response rate, with acceptable hematological and extrahematological toxicities in relapsed/refractory aggressive NHL. The role of lenalidomide as salvage therapy in both cell of origin patterns in DLBCL (germinal center B-cell/activated B-cell was reported in preliminary data. Preliminary data regarding the role of lenalidomide in addition to chemoimmunotherapy (R-CHOP in first line clinical trials were discussed; data of safety, feasibility and efficacy were promising.

  15. Small B cell lymphocytic lymphoma presenting as obstructive sleep apnea

    Directory of Open Access Journals (Sweden)

    Chang Weng-Cheng

    2004-07-01

    Full Text Available Abstract Background Most lymphomas that involve the tonsil are large B cell lymphomas. Large B-cell lymphoma is a high grade malignancy which progresses rapidly. Tonsillar lymphoma usually presents as either a unilaterally enlarged palatine tonsil or as an ulcerative and fungating lesion over the tonsillar area. Small lymphocytic lymphomas (SLL of the Waldeyer's ring are uncommon. Case presentation We report a 41-year-old male who presented with a ten-year history of snoring. Physical examination revealed smooth bilateral symmetrically enlarged tonsils without abnormal surface change or cervical lymphadenopathy. Palatal redundancy and a narrowed oropharyngeal airway were also noted. The respiratory disturbance index (RDI was 66 per hour, and severe obstruction sleep apnea (OSA was suspected. No B symptoms, sore throat, odynophagia or dysphagia was found. We performed uvulopalatopharyngoplasty (UPPP and pathological examination revealed incidental small B-cell lymphocytic lymphoma (SLL. Conclusion It is uncommon for lymphoma to initially present as OSA. SLL is an indolent malignancy and is not easy to detect in the early stage. We conclude that SLL may be a contributing factor of OSA in the present case.

  16. Benchmarking biofuels; Biobrandstoffen benchmarken

    Energy Technology Data Exchange (ETDEWEB)

    Croezen, H.; Kampman, B.; Bergsma, G.

    2012-03-15

    A sustainability benchmark for transport biofuels has been developed and used to evaluate the various biofuels currently on the market. For comparison, electric vehicles, hydrogen vehicles and petrol/diesel vehicles were also included. A range of studies as well as growing insight are making it ever clearer that biomass-based transport fuels may have just as big a carbon footprint as fossil fuels like petrol or diesel, or even bigger. At the request of Greenpeace Netherlands, CE Delft has brought together current understanding on the sustainability of fossil fuels, biofuels and electric vehicles, with particular focus on the performance of the respective energy carriers on three sustainability criteria, with the first weighing the heaviest: (1) Greenhouse gas emissions; (2) Land use; and (3) Nutrient consumption [Dutch] Greenpeace Nederland heeft CE Delft gevraagd een duurzaamheidsmeetlat voor biobrandstoffen voor transport te ontwerpen en hierop de verschillende biobrandstoffen te scoren. Voor een vergelijk zijn ook elektrisch rijden, rijden op waterstof en rijden op benzine of diesel opgenomen. Door onderzoek en voortschrijdend inzicht blijkt steeds vaker dat transportbrandstoffen op basis van biomassa soms net zoveel of zelfs meer broeikasgassen veroorzaken dan fossiele brandstoffen als benzine en diesel. CE Delft heeft voor Greenpeace Nederland op een rijtje gezet wat de huidige inzichten zijn over de duurzaamheid van fossiele brandstoffen, biobrandstoffen en elektrisch rijden. Daarbij is gekeken naar de effecten van de brandstoffen op drie duurzaamheidscriteria, waarbij broeikasgasemissies het zwaarst wegen: (1) Broeikasgasemissies; (2) Landgebruik; en (3) Nutriëntengebruik.

  17. California commercial building energy benchmarking

    Energy Technology Data Exchange (ETDEWEB)

    Kinney, Satkartar; Piette, Mary Ann

    2003-07-01

    Building energy benchmarking is the comparison of whole-building energy use relative to a set of similar buildings. It provides a useful starting point for individual energy audits and for targeting buildings for energy-saving measures in multiple-site audits. Benchmarking is of interest and practical use to a number of groups. Energy service companies and performance contractors communicate energy savings potential with ''typical'' and ''best-practice'' benchmarks while control companies and utilities can provide direct tracking of energy use and combine data from multiple buildings. Benchmarking is also useful in the design stage of a new building or retrofit to determine if a design is relatively efficient. Energy managers and building owners have an ongoing interest in comparing energy performance to others. Large corporations, schools, and government agencies with numerous facilities also use benchmarking methods to compare their buildings to each other. The primary goal of Task 2.1.1 Web-based Benchmarking was the development of a web-based benchmarking tool, dubbed Cal-Arch, for benchmarking energy use in California commercial buildings. While there were several other benchmarking tools available to California consumers prior to the development of Cal-Arch, there were none that were based solely on California data. Most available benchmarking information, including the Energy Star performance rating, were developed using DOE's Commercial Building Energy Consumption Survey (CBECS), which does not provide state-level data. Each database and tool has advantages as well as limitations, such as the number of buildings and the coverage by type, climate regions and end uses. There is considerable commercial interest in benchmarking because it provides an inexpensive method of screening buildings for tune-ups and retrofits. However, private companies who collect and manage consumption data are concerned that the

  18. Benchmarking in water project analysis

    Science.gov (United States)

    Griffin, Ronald C.

    2008-11-01

    The with/without principle of cost-benefit analysis is examined for the possible bias that it brings to water resource planning. Theory and examples for this question are established. Because benchmarking against the demonstrably low without-project hurdle can detract from economic welfare and can fail to promote efficient policy, improvement opportunities are investigated. In lieu of the traditional, without-project benchmark, a second-best-based "difference-making benchmark" is proposed. The project authorizations and modified review processes instituted by the U.S. Water Resources Development Act of 2007 may provide for renewed interest in these findings.

  19. Manipulation of immunodominant dengue virus E protein epitopes reduces potential antibody-dependent enhancement

    Directory of Open Access Journals (Sweden)

    Hughes Holly R

    2012-06-01

    Full Text Available Abstract Background Dengue viruses (DENV are the most important arboviruses of humans and cause significant disease. Infection with DENV elicits antibody responses to the envelope glycoprotein, predominantly against immunodominant, cross-reactive, weakly-neutralizing epitopes. These weakly-neutralizing antibodies are implicated in enhancing infection via Fcγ receptor bearing cells and can lead to increased viral loads that are associated with severe disease. Here we describe results from the development and testing of cross-reactivity reduced DENV-2 DNA vaccine candidates that contain substitutions in immunodominant B cell epitopes of the fusion peptide and domain III of the envelope protein. Results Cross-reactivity reduced and wild-type vaccine candidates were similarly immunogenic in outbred mice and elicited high levels of neutralizing antibody, however mice immunized with cross-reactivity reduced vaccines produced significantly reduced levels of immunodominant cross-reactive antibodies. Sera from mice immunized with wild-type, fusion peptide-, or domain III- substitution containing vaccines enhanced heterologous DENV infection in vitro, unlike sera from mice immunized with a vaccine containing a combination of both fusion peptide and domain III substitutions. Passive transfer of immune sera from mice immunized with fusion peptide and domain III substitutions also reduced the development of severe DENV disease in AG129 mice when compared to mice receiving wild type immune sera. Conclusions Reducing cross-reactivity in the envelope glycoprotein of DENV may be an approach to improve the quality of the anti-DENV immune response.

  20. Extensive Citrullination Promotes Immunogenicity of HSP90 through Protein Unfolding and Exposure of Cryptic Epitopes.

    Science.gov (United States)

    Travers, Timothy S; Harlow, Lisa; Rosas, Ivan O; Gochuico, Bernadette R; Mikuls, Ted R; Bhattacharya, Sanjoy K; Camacho, Carlos J; Ascherman, Dana P

    2016-09-01

    Post-translational protein modifications such as citrullination have been linked to the breach of immune tolerance and clinical autoimmunity. Previous studies from our laboratory support this concept, demonstrating that autoantibodies targeting citrullinated isoforms of heat shock protein 90 (HSP90) are associated with rheumatoid arthritis complicated by interstitial lung disease. To further explore the relationship between citrullination and structural determinants of HSP90 immunogenicity, we employed a combination of ELISA-based epitope profiling, computational modeling, and mass-spectrometric sequencing of peptidylarginine deiminase (PAD)-modified protein. Remarkably, ELISAs involving selected citrullinated HSP90β/α peptides identified a key epitope corresponding to an internal Arg residue (R502 [HSP90β]/R510 [HSP90α]) that is normally buried within the crystal structure of native/unmodified HSP90. In vitro time/dose-response experiments reveal an ordered pattern of PAD-mediated deimination events culminating in citrullination of R502/R510. Conventional as well as scaled molecular dynamics simulations further demonstrate that citrullination of selected Arg residues leads to progressive disruption of HSP90 tertiary structure, promoting exposure of R502/R510 to PAD modification and subsequent autoantibody binding. Consistent with this process, ELISAs incorporating variably deiminated HSP90 as substrate Ag indicate a direct relationship between the degree of citrullination and the level of ex vivo Ab recognition. Overall, these data support a novel structural paradigm whereby citrullination-induced shifts in protein structure generate cryptic epitopes capable of bypassing B cell tolerance in the appropriate genetic context.

  1. In Vitro Evolution of Allergy Vaccine Candidates, with Maintained Structure, but Reduced B Cell and T Cell Activation Capacity

    Science.gov (United States)

    Nilsson, Ola B.; Adedoyin, Justus; Rhyner, Claudio; Neimert-Andersson, Theresa; Grundström, Jeanette; Berndt, Kurt D.; Crameri, Reto; Grönlund, Hans

    2011-01-01

    Allergy and asthma to cat (Felis domesticus) affects about 10% of the population in affluent countries. Immediate allergic symptoms are primarily mediated via IgE antibodies binding to B cell epitopes, whereas late phase inflammatory reactions are mediated via activated T cell recognition of allergen-specific T cell epitopes. Allergen-specific immunotherapy relieves symptoms and is the only treatment inducing a long-lasting protection by induction of protective immune responses. The aim of this study was to produce an allergy vaccine designed with the combined features of attenuated T cell activation, reduced anaphylactic properties, retained molecular integrity and induction of efficient IgE blocking IgG antibodies for safer and efficacious treatment of patients with allergy and asthma to cat. The template gene coding for rFel d 1 was used to introduce random mutations, which was subsequently expressed in large phage libraries. Despite accumulated mutations by up to 7 rounds of iterative error-prone PCR and biopanning, surface topology and structure was essentially maintained using IgE-antibodies from cat allergic patients for phage enrichment. Four candidates were isolated, displaying similar or lower IgE binding, reduced anaphylactic activity as measured by their capacity to induce basophil degranulation and, importantly, a significantly lower T cell reactivity in lymphoproliferative assays compared to the original rFel d 1. In addition, all mutants showed ability to induce blocking antibodies in immunized mice.The approach presented here provides a straightforward procedure to generate a novel type of allergy vaccines for safer and efficacious treatment of allergic patients. PMID:21931754

  2. In vitro evolution of allergy vaccine candidates, with maintained structure, but reduced B cell and T cell activation capacity.

    Science.gov (United States)

    Nilsson, Ola B; Adedoyin, Justus; Rhyner, Claudio; Neimert-Andersson, Theresa; Grundström, Jeanette; Berndt, Kurt D; Crameri, Reto; Grönlund, Hans

    2011-01-01

    Allergy and asthma to cat (Felis domesticus) affects about 10% of the population in affluent countries. Immediate allergic symptoms are primarily mediated via IgE antibodies binding to B cell epitopes, whereas late phase inflammatory reactions are mediated via activated T cell recognition of allergen-specific T cell epitopes. Allergen-specific immunotherapy relieves symptoms and is the only treatment inducing a long-lasting protection by induction of protective immune responses. The aim of this study was to produce an allergy vaccine designed with the combined features of attenuated T cell activation, reduced anaphylactic properties, retained molecular integrity and induction of efficient IgE blocking IgG antibodies for safer and efficacious treatment of patients with allergy and asthma to cat. The template gene coding for rFel d 1 was used to introduce random mutations, which was subsequently expressed in large phage libraries. Despite accumulated mutations by up to 7 rounds of iterative error-prone PCR and biopanning, surface topology and structure was essentially maintained using IgE-antibodies from cat allergic patients for phage enrichment. Four candidates were isolated, displaying similar or lower IgE binding, reduced anaphylactic activity as measured by their capacity to induce basophil degranulation and, importantly, a significantly lower T cell reactivity in lymphoproliferative assays compared to the original rFel d 1. In addition, all mutants showed ability to induce blocking antibodies in immunized mice.The approach presented here provides a straightforward procedure to generate a novel type of allergy vaccines for safer and efficacious treatment of allergic patients.

  3. In vitro evolution of allergy vaccine candidates, with maintained structure, but reduced B cell and T cell activation capacity.

    Directory of Open Access Journals (Sweden)

    Ola B Nilsson

    Full Text Available Allergy and asthma to cat (Felis domesticus affects about 10% of the population in affluent countries. Immediate allergic symptoms are primarily mediated via IgE antibodies binding to B cell epitopes, whereas late phase inflammatory reactions are mediated via activated T cell recognition of allergen-specific T cell epitopes. Allergen-specific immunotherapy relieves symptoms and is the only treatment inducing a long-lasting protection by induction of protective immune responses. The aim of this study was to produce an allergy vaccine designed with the combined features of attenuated T cell activation, reduced anaphylactic properties, retained molecular integrity and induction of efficient IgE blocking IgG antibodies for safer and efficacious treatment of patients with allergy and asthma to cat. The template gene coding for rFel d 1 was used to introduce random mutations, which was subsequently expressed in large phage libraries. Despite accumulated mutations by up to 7 rounds of iterative error-prone PCR and biopanning, surface topology and structure was essentially maintained using IgE-antibodies from cat allergic patients for phage enrichment. Four candidates were isolated, displaying similar or lower IgE binding, reduced anaphylactic activity as measured by their capacity to induce basophil degranulation and, importantly, a significantly lower T cell reactivity in lymphoproliferative assays compared to the original rFel d 1. In addition, all mutants showed ability to induce blocking antibodies in immunized mice.The approach presented here provides a straightforward procedure to generate a novel type of allergy vaccines for safer and efficacious treatment of allergic patients.

  4. Water Level Superseded Benchmark Sheets

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Images of National Coast & Geodetic Survey (now NOAA's National Geodetic Survey/NGS) tidal benchmarks which have been superseded by new markers or locations....

  5. Benchmarking and Sustainable Transport Policy

    DEFF Research Database (Denmark)

    Gudmundsson, Henrik; Wyatt, Andrew; Gordon, Lucy

    2004-01-01

    Order to learn from the best. In 2000 the European Commission initiated research to explore benchmarking as a tool to promote policies for ‘sustainable transport’. This paper reports findings and recommendations on how to address this challenge. The findings suggest that benchmarking is a valuable...... tool that may indeed help to move forward the transport policy agenda. However, there are major conditions and limitations. First of all it is not always so straightforward to delimit, measure and compare transport services in order to establish a clear benchmark. Secondly ‘sustainable transport......’ evokes a broad range of concerns that are hard to address fully at the level of specific practices. Thirdly policies are not directly comparable across space and context. For these reasons attempting to benchmark ‘sustainable transport policies’ against one another would be a highly complex task, which...

  6. Generation of cytotoxic T lymphocytes specific for B-cell acute lymphoblastic leukemia family-shared peptides derived from immunoglobulin heavy chain framework region

    Institute of Scientific and Technical Information of China (English)

    LIU Ying; ZHU Ping; HU Ya-mei

    2007-01-01

    Background Immunoglobulin heavy chain variable region (IgHV) is a well-characterized tumor antigen for B-cell malignancies. It can function as a target for T cell-mediated immune response. Clinical trials of IgHV protein vaccines against lymphoma have demonstrated induction of tumor-specific cytotoxic T lymphocyte (CTL) responses. However,complementary determining regions-based individual vaccines have disadvantages for wide clinical application. Although a recent study demonstrated that immunogenic peptides are derived from framework regions (FR) shared among patients with B-cell lymphoma, how to choose the appropriate peptides for each patient is still unsolved. The aim of this study was to investigate whether immunoglobulin heavy chain FR-derived peptides shared in each IgHV family are potential CTL epitopes presented by B-cell acute lymphoblastic leukemia (B-ALL). Such CTL epitopes might be beneficial to shifting vaccination strategies against B-ALL from individual specificity to family specificity.Methods Seven IgHV gene families were amplified respectively by PCR and sequenced directly from 71 childhood B-ALL cases. Bioinformatics was applied in analyzing characteristics of sequences available and predicting HLA-A*0201-restricted CTL epitopes for each IgHV family. An antigen-specific T cell expansion system was used to generate peptide-specific CTLs. The cytotoxicity of CTLs against B-ALL cells was assessed in the lactate dehydrogenase release assay.Results Complete IgHV rearrangements were identified in all of the 71 B-ALL cases. All of 40 sequences available showed ≥98% homology with the nearest germline IgHV genes, indicating IgHV genes in B-ALL of germline nature.Twelve nonapeptides of high HLA-A*0201-binding scores were obtained from 26 productive IgHV protein sequences. Ten (83%) of the peptides were located in FR1 and FR3 shared among the corresponding IgHV family. CTLs specific for the peptide QLVQSGAEV located in FR1 (3-11) shared among the IgHV1

  7. Deletion modification enhances anthrax specific immunity and protective efficacy of a hepatitis B core particle-based anthrax epitope vaccine.

    Science.gov (United States)

    Yin, Ying; Zhang, Sheng; Cai, Chenguang; Zhang, Jun; Dong, Dayong; Guo, Qiang; Fu, Ling; Xu, Junjie; Chen, Wei

    2014-02-01

    Protective antigen (PA) is one of the major virulence factors of anthrax and is also the major constituent of the current anthrax vaccine. Previously, we found that the 2β2-2β3 loop of PA contains a dominant neutralizing epitope, the SFFD. We successfully inserted the 2β2-2β3 loop of PA into the major immunodominant region (MIR) of hepatitis B virus core (HBc) protein. The resulting fusion protein, termed HBc-N144-PA-loop2 (HBcL2), can effectively produce anthrax specific protective antibodies in an animal model. However, the protective immunity caused by HBcL2 could still be improved. In this research, we removed amino acids 79-81 from the HBc MIR of the HBcL2. This region was previously reported to be the major B cell epitope of HBc, and in keeping with this finding, we observed that the short deletion in the MIR not only diminished the intrinsic immunogenicity of HBc but also stimulated a higher titer of anthrax specific immunity. Most importantly, this deletion led to the full protection of the immunized mice against a lethal dose anthrax toxin challenge. We supposed that the conformational changes which occurred after the short deletion and foreign insertion in the MIR of HBc were the most likely reasons for the improvement in the immunogenicity of the HBc-based anthrax epitope vaccine.

  8. Deletion modification enhances anthrax specific immunity and protective efficacy of a hepatitis B core particle-based anthrax epitope vaccine.

    Science.gov (United States)

    Yin, Ying; Zhang, Sheng; Cai, Chenguang; Zhang, Jun; Dong, Dayong; Guo, Qiang; Fu, Ling; Xu, Junjie; Chen, Wei

    2014-02-01

    Protective antigen (PA) is one of the major virulence factors of anthrax and is also the major constituent of the current anthrax vaccine. Previously, we found that the 2β2-2β3 loop of PA contains a dominant neutralizing epitope, the SFFD. We successfully inserted the 2β2-2β3 loop of PA into the major immunodominant region (MIR) of hepatitis B virus core (HBc) protein. The resulting fusion protein, termed HBc-N144-PA-loop2 (HBcL2), can effectively produce anthrax specific protective antibodies in an animal model. However, the protective immunity caused by HBcL2 could still be improved. In this research, we removed amino acids 79-81 from the HBc MIR of the HBcL2. This region was previously reported to be the major B cell epitope of HBc, and in keeping with this finding, we observed that the short deletion in the MIR not only diminished the intrinsic immunogenicity of HBc but also stimulated a higher titer of anthrax specific immunity. Most importantly, this deletion led to the full protection of the immunized mice against a lethal dose anthrax toxin challenge. We supposed that the conformational changes which occurred after the short deletion and foreign insertion in the MIR of HBc were the most likely reasons for the improvement in the immunogenicity of the HBc-based anthrax epitope vaccine. PMID:24054942

  9. Research on computer systems benchmarking

    Science.gov (United States)

    Smith, Alan Jay (Principal Investigator)

    1996-01-01

    This grant addresses the topic of research on computer systems benchmarking and is more generally concerned with performance issues in computer systems. This report reviews work in those areas during the period of NASA support under this grant. The bulk of the work performed concerned benchmarking and analysis of CPUs, compilers, caches, and benchmark programs. The first part of this work concerned the issue of benchmark performance prediction. A new approach to benchmarking and machine characterization was reported, using a machine characterizer that measures the performance of a given system in terms of a Fortran abstract machine. Another report focused on analyzing compiler performance. The performance impact of optimization in the context of our methodology for CPU performance characterization was based on the abstract machine model. Benchmark programs are analyzed in another paper. A machine-independent model of program execution was developed to characterize both machine performance and program execution. By merging these machine and program characterizations, execution time can be estimated for arbitrary machine/program combinations. The work was continued into the domain of parallel and vector machines, including the issue of caches in vector processors and multiprocessors. All of the afore-mentioned accomplishments are more specifically summarized in this report, as well as those smaller in magnitude supported by this grant.

  10. Implementation of Benchmarking Transportation Logistics Practices and Future Benchmarking Organizations

    International Nuclear Information System (INIS)

    The purpose of the Office of Civilian Radioactive Waste Management's (OCRWM) Logistics Benchmarking Project is to identify established government and industry practices for the safe transportation of hazardous materials which can serve as a yardstick for design and operation of OCRWM's national transportation system for shipping spent nuclear fuel and high-level radioactive waste to the proposed repository at Yucca Mountain, Nevada. The project will present logistics and transportation practices and develop implementation recommendations for adaptation by the national transportation system. This paper will describe the process used to perform the initial benchmarking study, highlight interim findings, and explain how these findings are being implemented. It will also provide an overview of the next phase of benchmarking studies. The benchmarking effort will remain a high-priority activity throughout the planning and operational phases of the transportation system. The initial phase of the project focused on government transportation programs to identify those practices which are most clearly applicable to OCRWM. These Federal programs have decades of safe transportation experience, strive for excellence in operations, and implement effective stakeholder involvement, all of which parallel OCRWM's transportation mission and vision. The initial benchmarking project focused on four business processes that are critical to OCRWM's mission success, and can be incorporated into OCRWM planning and preparation in the near term. The processes examined were: transportation business model, contract management/out-sourcing, stakeholder relations, and contingency planning. More recently, OCRWM examined logistics operations of AREVA NC's Business Unit Logistics in France. The next phase of benchmarking will focus on integrated domestic and international commercial radioactive logistic operations. The prospective companies represent large scale shippers and have vast experience in

  11. Characterization of xenoantiserum produced against B cell acute lymphoblastic leukemia cell line

    Directory of Open Access Journals (Sweden)

    Akagi,Tadaatsu

    1982-10-01

    Full Text Available Antiserum was produced in white rabbit by intravenously injecting living cells of a B cell acute lymphoblastic leukemia (ALL line (BALL-1. The reactivity of the antiserum against various lymphoid cell lines was examined by membrane immunofluorescence after appropriate absorption. Serum absorbed with non-T, non-B (NALL-1 and T-ALL (TALL-1 cells recognized B cell antigens distinct from Ia-like antigens on both normal and neoplastic B cells. After further absorption with tonsillar cells or normal B cell line (KO-HL-3, it reacted only with BALL-1 cells and did not react with other leukemia/lymphoma and normal B cell lines. The serum absorbed with tonsillar cells reacted only with BALL-1 and some B cell lines. Thus we were able to obtain antisera with specificity to B cell antigen, B-ALL antigen, and B cell line antigen.

  12. B cells exposed to enterobacterial components suppress development of experimental colitis

    DEFF Research Database (Denmark)

    Schmidt, Esben Gjerløff Wedebye; Larsen, Hjalte List; Kristensen, Nanna Ny;

    2012-01-01

    BACKGROUND: B cells positively contribute to immunity by antigen presentation to CD4(+) T cells, cytokine production, and differentiation into antibody secreting plasma cells. Accumulating evidence implies that B cells also possess immunoregulatory functions closely linked to their capability of ...

  13. Cyclin Dl expression in B-cell non Hodgkin lymphoma.

    Science.gov (United States)

    Aref, Salah; Mossad, Y; El-Khodary, T; Awad, M; El-Shahat, E

    2006-10-01

    Disorders of the cell cycle regulatory machinery play a key role in the pathogenesis of cancer. Over-expression of cyclin D1 protein has been reported in several solid tumors and certain lymphoid malignancies, but little is known about the effect of its expression on clinical behavior and outcome in B-cell Non-Hodgkin lymphoma (NHL). In this study, we investigated the expression of cyclin Dl in group of patients with NHL and correlated the results with the clinical and laboratory data. The degree of expression of cyclin Dl protein was evaluated by flow cytometry in a group of NHL patients (n = 46) and in normal control group (n = 10). Cyclin Dl over expression was detected in 10 out of 46 (21.7%) patients; they were 5/5-mantle cell lymphoma (MCL) (100%) and 5/28 large B-cell lymphoma (17.8%). All other NHL subtypes showed normal cyclin D1 expression. The clinical signs (hepatomegaly, splenomegaly and B-symptoms, clinical staging) and laboratory data (hemoglobin, white cell count (WBCs), platelet count, and bone marrow infiltration) were not significantly different between NHL subgroup with cyclin Dl over expression and that with normal cyclin Dl expression. Serum lactic dehydrogenase (LDH) levels and lymphadenopathy were significantly higher in NHL group with cyclin D1 over expression as compared to those without. Also, cyclin D1 over expression is associated with poor outcome of NHL patients. Cyclin Dl over expression was evident among all cases of MCL and few cases of large B-cell lymphoma. Cyclin Dl over expression might be used as adjuvant tool for diagnosis of MCL; has role in NHL biology and is bad prognostic index in NHL. PMID:17607588

  14. B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma: Report of a case in the oral cavity

    Directory of Open Access Journals (Sweden)

    Jumana M Jaradat

    2013-01-01

    Full Text Available B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma (DLBCL/BL is a new category of B-cell lymphoma according to the 4 th edition of the World Health Organization Classification of Tumours of Haematopoietic and Lymphoid Tissues (2008. The following report presents a case of this rare, newly described entity on the palate of a 59 year-old male.

  15. Proof of principle for epitope-focused vaccine design

    Science.gov (United States)

    Correia, Bruno E.; Bates, John T.; Loomis, Rebecca J.; Baneyx, Gretchen; Carrico, Chris; Jardine, Joseph G.; Rupert, Peter; Correnti, Colin; Kalyuzhniy, Oleksandr; Vittal, Vinayak; Connell, Mary J.; Stevens, Eric; Schroeter, Alexandria; Chen, Man; MacPherson, Skye; Serra, Andreia M.; Adachi, Yumiko; Holmes, Margaret A.; Li, Yuxing; Klevit, Rachel E.; Graham, Barney S.; Wyatt, Richard T.; Baker, David; Strong, Roland K.; Crowe, James E.; Johnson, Philip R.; Schief, William R.

    2014-03-01

    Vaccines prevent infectious disease largely by inducing protective neutralizing antibodies against vulnerable epitopes. Several major pathogens have resisted traditional vaccine development, although vulnerable epitopes targeted by neutralizing antibodies have been identified for several such cases. Hence, new vaccine design methods to induce epitope-specific neutralizing antibodies are needed. Here we show, with a neutralization epitope from respiratory syncytial virus, that computational protein design can generate small, thermally and conformationally stable protein scaffolds that accurately mimic the viral epitope structure and induce potent neutralizing antibodies. These scaffolds represent promising leads for the research and development of a human respiratory syncytial virus vaccine needed to protect infants, young children and the elderly. More generally, the results provide proof of principle for epitope-focused and scaffold-based vaccine design, and encourage the evaluation and further development of these strategies for a variety of other vaccine targets, including antigenically highly variable pathogens such as human immunodeficiency virus and influenza.

  16. Hepatitis C virus - associated B cell non-Hodgkin's lymphoma

    Science.gov (United States)

    Mihăilă, Romeo-Gabriel

    2016-01-01

    The hepatitis C virus (HCV) infected patients are prone to develop bone marrow or various tissue infiltrates with monoclonal B cells, monoclonal B lymphocytosis or different types of B cell non-Hodgkin’s lymphoma (BCNHL), of which the most common are splenic marginal zone BCNHL, diffuse large BCNHL and follicular lymphoma. The association between chronic HCV infection and non Hodgkin’s lymphoma has been observed especially in areas with high prevalence of this viral infection. Outside the limitations of some studies that have been conducted, there are also geographic, environmental, and genetic factors that contribute to the epidemiological differences. Various microenvironmental signals, such as cytokines, viral antigenic external stimulation of lymphocyte receptors by HCV antigens, and intercellular interactions contribute to B cell proliferation. HCV lymphotropism and chronic antigenic stimulation are involved in B-lymphocyte expansion, as mixted cryoglobulinemia or monoclonal gammopathy of undetermined significance, which can progress to BCNHL. HCV replication in B lymphocytes has oncogenic effect mediated by intracellular HCV proteins. It is also involved in an important induction of reactive oxygen species that can lead to permanent B lymphocyte damage, as DNA mutations, after binding to surface B-cell receptors. Post-transplant lymphoproliferative disorder could appear and it has a multiclonal potentiality that may develop into different types of lymphomas. The hematopoietic stem cell transplant made for lymphoma in HCV-infected patients can increase the risk of earlier progression to liver fibrosis and cirrhosis. HCV infected patients with indolent BCNHL who receive antiviral therapy can be potentially cured. Viral clearance was related to lymphoma response, fact that highlights the probable involvement of HCV in lymphomagenesis. Direct acting antiviral drugs could be a solution for the patients who did not tolerate or respond to interferon, as they

  17. Differential Effects of Tacrolimus versus Sirolimus on the Proliferation, Activation and Differentiation of Human B Cells

    OpenAIRE

    Traitanon, Opas; Mathew, James M.; La Monica, Giovanna; Xu, Luting; Mas, Valeria; Gallon, Lorenzo

    2015-01-01

    The direct effect of immunosuppressive drugs calcineurin inhibitor (Tacrolimus, TAC) and mTOR inhibitor (Sirolimus, SRL) on B cell activation, differentiation and proliferation is not well documented. Purified human B cells from healthy volunteers were stimulated through the B Cell Receptor with Anti-IgM + anti-CD40 + IL21 in the absence / presence of TAC or SRL. A variety of parameters of B cell activity including activation, differentiation, cytokine productions and proliferation were monit...

  18. Identification of Functional Human Splenic Memory B Cells by Expression of CD148 and CD27

    OpenAIRE

    Tangye, Stuart G.; Liu, Yong-Jun; Aversa, Gregorio; Phillips, Joseph H.; Vries, Jan E. de

    1998-01-01

    Memory B cells isolated from human tonsils are characterized by an activated cell surface phenotype, localization to mucosal epithelium, expression of somatically mutated immunoglobulin (Ig) variable (V) region genes, and a preferential differentiation into plasma cells in vitro. In spleens of both humans and rodents, a subset of memory B cells is believed to reside in the marginal zone of the white pulp. Similar to tonsil-derived memory B cells, splenic marginal zone B cells can be distingui...

  19. Targeting Bruton's tyrosine kinase signaling as an emerging therapeutic agent of B-cell malignancies

    OpenAIRE

    Xia, Bing; QU, FULIAN; Yuan, Tian; Zhang, Yizhuo

    2015-01-01

    It is becoming increasingly evident that B-cell receptor (BCR) signaling is central to the development and function of B cells. BCR signaling has emerged as a pivotal pathway and a key driver of numerous B-cell lymphomas. Disruption of BCR signaling can be lethal to malignant B cells. Recently, kinase inhibitors that target BCR signaling have induced notable clinical responses. These inhibitors include spleen tyrosine kinase, mammalian target of rapamycin, phosphoinositide 3′-kinase and Bruto...

  20. Aggressive B-cell lymphomas: how many categories do we need?

    OpenAIRE

    Said, Jonathan W.

    2012-01-01

    Aggressive B-cell lymphomas are diverse group of neoplasms that arise at different stages of B-cell development and by various mechanisms of neoplastic transformation. The aggressive B-cell lymphomas include many types, subtypes and variants of diffuse large B-cell lymphoma (DLBCL), Burkitt lymphoma (BL), mantle cell lymphoma and its blastoid variant, and B lymphoblastic lymphoma. Differences in histology, cytogenetic and molecular abnormalities, as well as the relationship with the tumor mic...

  1. Complement receptor 2, natural antibodies and innate immunity: Inter-relationships in B cell selection and activation.

    Science.gov (United States)

    Holers, V Michael; Kulik, Liudmila

    2007-01-01

    Complement receptor type 2 (CR2) is a receptor that serves as an important interface between the complement system and adaptive immunity. Recent studies have shown that CR2 is also centrally involved in innate immunity, and one key area is the development of potentially pathogenic natural antibodies that target neo-epitopes revealed in ischemic tissue undergoing reperfusion. Mice lacking either total immunoglobulins or CR2 alone are protected from the development of ischemia-reperfusion injury, and this effect can be reversed by introducing CR2-sufficient B-1 cells or by transferring polyclonal natural IgM antibody from wild type mice as well as monoclonal antibodies that recognize phospholipids, DNA or non-muscle myosin. We will report at the XXI ICW an additional membrane-associated protein to which pathogenic IgM antibodies are directed. Whether B cells producing these natural antibodies are differentially selected in CR2-deficient mice is as yet not well understood, and the complement-related mechanism(s) whereby this differential repertoire selection process could occur have yet to be explored in any detail. In addition to this important role in innate immunity, CR2 can also act as a receptor for other components or activators of innate immunity. One such component is interferon-alpha, an anti-viral cytokine that binds CR2 and induces a component of its mRNA signature in B cells through this receptor. Other potential CR2 ligands are DNA and DNA-containing complexes such as chromatin. The biologic role of these CR2 interactions with interferon-alpha and DNA-containing complexes is not well understood, but may be important in the development of the autoimmune disease systemic lupus erythematosus that is characterized by enhanced interferon-alpha levels and loss of self tolerance to DNA-containing self antigens. PMID:16876864

  2. B cell stimulatory factor 1 (BSF-1) prepares resting B cells to enter S phase in response to anti-IgM and lipopolysaccharide

    OpenAIRE

    1986-01-01

    BSF-1 prepares resting BALB/c, DBA/2, and BDF1 B cells to enter S phase more promptly in response to subsequent culture with anti-IgM-based stimulants. It prepares DBA/2 and BDF1 B cells to respond to LPS, but its preparative effect for LPS responses of BALB/c B cells is both inconstant and meager. Preparation mediated by BSF-1 requires extended contact of B cells with the stimulant for full effect. Half-maximal preparation requires approximately 12 h of contact, as judged by delayed addition...

  3. PAX5 promotes pre-B cell proliferation by regulating the expression of pre-B cell receptor and its downstream signaling.

    Science.gov (United States)

    Xue, Kai; Song, Jiazhe; Yang, Yan; Li, Zhi; Wu, Chunhua; Jin, Jinhua; Li, Wenzhe

    2016-05-01

    PAX5 is indispensable for the commitment of early lymphoid progenitors to the B cell lineage as well as for the development of B cells. Although previous studies have indicated that the Pax5-conditional-knockout mouse exhibited dedifferentiation of mature B cell and the development of aggressive lymphomas, the changes of Pax5 gene expressions in pre-B cells have not been analyzed. To understand the functional importance of Pax5 gene in the proliferation and survival of pre-B cells, we established a Pax5-knockdown model using 70Z/3 pre-B cell line. Pax5 knockdown 70Z/3 cells (70Z/3-KD cells) showed down-regulations of pre-BCR compounds such as CD19, BLNK, Id2 and λ5. The signaling via pre-BCRs was significantly diminished in the 70Z/3-KD cells, and this alteration was normalized by restored Pax5 gene expression. Loss of PAX5 reduced the growth rates in the 70Z/3-KD cells, compared to the mock cells. Meanwhile, the proliferation of pre-B cells was reduced by the knockdown of Pax5 gene. Moreover, further examinations showed that PAX5 was also activated in B cell acute lymphoblastic leukemia (B-ALL) as a cell proliferation enhancer. These findings suggested that pax5 is critically important for the proliferation and survival of pre-B cells. PMID:27016671

  4. In silico design of discontinuous peptides representative of B and T-cell epitopes from HER2-ECD as potential novel cancer peptide vaccines.

    Science.gov (United States)

    Manijeh, Mahdavi; Mehrnaz, Keyhanfar; Violaine, Moreau; Hassan, Mohabatkar; Abbas, Jafarian; Mohammad, Rabbani

    2013-01-01

    At present, the most common cause of cancer-related death in women is breast cancer. In a large proportion of breast cancers, there is the overexpression of human epidermal growth factor receptor 2 (HER2). This receptor is a 185 KDa growth factor glycoprotein, also known as the first tumor-associated antigen for different types of breast cancers. Moreover, HER2 is an appropriate cell-surface specific antigen for passive immunotherapy, which relies on the repeated application of monoclonal antibodies that are transferred to the patient. However, vaccination is preferable because it would stimulate a patient's own immune system to actively respond to a disease. In the current study, several bioinformatics tools were used for designing synthetic peptide vaccines. PEPOP was used to predict peptides from HER2 ECD subdomain III in the form of discontinuous-continuous B-cell epitopes. Then, T-cell epitope prediction web servers MHCPred, SYFPEITHI, HLA peptide motif search, Propred, and SVMHC were used to identify class-I and II MHC peptides. In this way, PEPOP selected 12 discontinuous peptides from the 3D structure of the HER2 ECD subdomain III. Furthermore, T-cell epitope prediction analyses identified four peptides containing the segments 77 (384-391) and 99 (495-503) for both B and T-cell epitopes. This work is the only study to our knowledge focusing on design of in silico potential novel cancer peptide vaccines of the HER2 ECD subdomain III that contain epitopes for both B and T-cells. These findings based on bioinformatics analyses may be used in vaccine design and cancer therapy; saving time and minimizing the number of tests needed to select the best possible epitopes.

  5. Multiple HLA Epitopes Contribute to Type 1 Diabetes Susceptibility

    OpenAIRE

    Roark, Christina L.; Anderson, Kirsten M.; Simon, Lucas J.; Schuyler, Ronald P.; Aubrey, Michael T; Freed, Brian M.

    2013-01-01

    Disease susceptibility for type 1 diabetes is strongly associated with the inheritance of specific HLA alleles. However, conventional allele frequency analysis can miss HLA associations because many alleles are rare. In addition, disparate alleles that have similar peptide-binding sites, or shared epitopes, can be missed. To identify the HLA shared epitopes associated with diabetes, we analyzed high-resolution genotyping for class I and class II loci. The HLA epitopes most strongly associated...

  6. R-ICE and Lenalidomide in Treating Patients With First-Relapse/Primary Refractory Diffuse Large B-Cell Lymphoma

    Science.gov (United States)

    2015-12-30

    Diffuse Large B-Cell Lymphoma; Recurrent Diffuse Large B-Cell Lymphoma; Recurrent Mediastinal (Thymic) Large B-Cell Cell Lymphoma; Refractory Diffuse Large B-Cell Lymphoma; Refractory Mediastinal (Thymic) Large B-Cell Cell Lymphoma; Transformed Recurrent Non-Hodgkin Lymphoma

  7. File list: ALL.Bld.10.AllAg.Pro-B_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Bld.10.AllAg.Pro-B_cells mm9 All antigens Blood Pro-B cells SRX1553109,SRX15531...9,SRX1143902 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Bld.10.AllAg.Pro-B_cells.bed ...

  8. Cigarette smoke-induced emphysema : A role for the B cell?

    NARCIS (Netherlands)

    van der Strate, BWA; Postma, DS; Brandsma, CA; Melgert, BN; Luinge, MA; Geerlings, M; Hylkema, MN; van den Berg, Anke; Timens, W; Kerstjens, HAM

    2006-01-01

    Rationale: Little is known about what drives the inflammatory reaction in the development of chronic obstructive lung disease. B cells have been found. Objective: To study the involvement of B cells in the development of emphysema. Methods: The presence of B-cell follicles and their interaction with

  9. File list: His.Bld.50.AllAg.Pro-B_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Bld.50.AllAg.Pro-B_cells mm9 Histone Blood Pro-B cells SRX668836,SRX1184113,SRX...09,SRX759800,SRX1143916,SRX1143902 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Bld.50.AllAg.Pro-B_cells.bed ...

  10. File list: ALL.Bld.20.AllAg.Pro-B_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Bld.20.AllAg.Pro-B_cells mm9 All antigens Blood Pro-B cells SRX1553109,SRX15531...3,SRX1143907 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Bld.20.AllAg.Pro-B_cells.bed ...

  11. In vitro effects of rituximab on the proliferation, activation and differentiation of human B cells.

    NARCIS (Netherlands)

    Kamburova, E.G.; Koenen, H.J.P.M.; Boon, L.; Hilbrands, L.B.; Joosten, I.

    2012-01-01

    Rituximab is a chimeric anti-CD20 monoclonal antibody (mAb) used in B-cell malignancies, various autoimmune disorders and organ transplantation. Although administration of a single dose of rituximab results in full B-cell depletion in peripheral blood, there remains a residual B-cell population in s

  12. Characterization of Regulatory B Cells in Graves' Disease and Hashimoto's Thyroiditis

    DEFF Research Database (Denmark)

    Kristensen, Birte; Hegedüs, Laszlo; Lundy, Steven K;

    2015-01-01

    cells from patients with HT. In GD, B cells primed with TG induced IL-10-producing CD4+ T cells. To assess the maximal frequency of inducible IL-10+ B cells in the three donor groups PBMCs were stimulated with PMA/ionomycin. The resulting IL-10+ B-cell frequency was similar in the three groups and...

  13. Modulation of B-cell receptor and microenvironment signaling by a guanine exchange factor in B-cell malignancies

    Institute of Scientific and Technical Information of China (English)

    Wei Liao; Sanjai Sharma

    2016-01-01

    Objective: Chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL) cells over-express a guanine exchange factor (GEF), Rasgrf-1. This GEF increases active Ras as it catalyzes the removal of GDP from Ras so that GTP can bind and activate Ras. This study aims to study the mechanism of action of Rasgrf-1 in B-cell malignancies. Methods: N-terminus truncated Rasgrf-1 variants have a higher GEF activity as compared to the full-length transcript therefore a MCL cell line with stable over-expression of truncated Rasgrf-1 was established. The B-cell receptor (BCR) and chemokine signaling pathways were compared in the Rasgrf-1 over-expressing and a control transfected cell line. Results: Cells over-expressing truncated form of Rasgrf-1 have a higher proliferative rate as compared to control transfected cells. BCR was activated by lower concentrations of anti-IgM antibody in Rasgrf-1 over-expressing cells as compared to control cells indicating that these cells are more sensitive to BCR signaling. BCR signaling also phosphorylates Rasgrf-1 that further increases its GEF function and amplifies BCR signaling. This activation of Rasgrf-1 in over-expressing cells resulted in a higher expression of phospho-ERK, AKT, BTK and PKC-alpha as compared to control cells. Besides BCR, Rasgrf-1 over-expressing cells were also more sensitive to microenvironment stimuli as determined by resistance to apoptosis, chemotaxis and ERK pathway activation. Conclusions: This GEF protein sensitizes B-cells to BCR and chemokine mediated signaling and also upregulates a number of other signaling pathways which promotes growth and survival of these cells.

  14. MicroRNA signatures in B-cell lymphomas

    International Nuclear Information System (INIS)

    Accurate lymphoma diagnosis, prognosis and therapy still require additional markers. We explore the potential relevance of microRNA (miRNA) expression in a large series that included all major B-cell non-Hodgkin lymphoma (NHL) types. The data generated were also used to identify miRNAs differentially expressed in Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) samples. A series of 147 NHL samples and 15 controls were hybridized on a human miRNA one-color platform containing probes for 470 human miRNAs. Each lymphoma type was compared against the entire set of NHLs. BL was also directly compared with DLBCL, and 43 preselected miRNAs were analyzed in a new series of routinely processed samples of 28 BLs and 43 DLBCLs using quantitative reverse transcription-polymerase chain reaction. A signature of 128 miRNAs enabled the characterization of lymphoma neoplasms, reflecting the lymphoma type, cell of origin and/or discrete oncogene alterations. Comparative analysis of BL and DLBCL yielded 19 differentially expressed miRNAs, which were confirmed in a second confirmation series of 71 paraffin-embedded samples. The set of differentially expressed miRNAs found here expands the range of potential diagnostic markers for lymphoma diagnosis, especially when differential diagnosis of BL and DLBCL is required

  15. Dominant neurologic symptomatology in intravascular large B-cell lymphoma.

    Science.gov (United States)

    Kubisova, K; Martanovic, P; Sisovsky, V; Tomleinova, Z; Steno, A; Janega, P; Rychly, B; Babal, P

    2016-01-01

    Intravascular large B-cell lymphoma (IVLBCL) is a rare variant of extranodal large B-cell lymphoma and it is characterized by selective intravascular proliferation of malignant cells. Typical features of the disease include aggressive behavior, rapid and frequently fatal course. Clinical picture is non-specific and heterogeneous, depending on the affected organ. It is not uncommon that this unique type of lymphoma is diagnosed post mortem. Herein, we report two cases of IVLBCL with neurologic symptomatology. In our clinical study patient 1 was an 80-year-old male with mixed paraparesis of lower extremities and difficulties with sphincter control. Patient 2 (56-year-old male) had vision malfunction, mental status changes and defect in phatic and motor functions. In both cases definite diagnosis was established by histological examination of necroptic material. We propose to include IVLBCL in differential diagnostic considerations in patients presenting with gradually impairing neurological status and spinal cord damage of unknown etiology (Fig. 2, Ref. 9). PMID:27546361

  16. Diffuse Large B Cell Lymphoma with Extensive Cutaneous Relapse

    Science.gov (United States)

    Malkan, Umit Yavuz; Gunes, Gursel; Yayar, Okan; Demiroglu, Haluk

    2015-01-01

    Herein, we aimed to report a diffuse large B cell lymphoma (DLBCL) case that had extensive cutaneous relapse with no skin involvement previously. A 59-year-old man presented to hospital in April 2014 with fatigue, anorexia, fever, and anemia. Cervical lymph node biopsy revealed CD20+, BCL2+, MUM1+, BCL6+ high grade B lymphoproliferative neoplasm. After FISH investigation, he was diagnosed as DLBCL. He was given 7 cycles of R-CHOP and achieved remission. However, in November 2014, he had emerging skin lesions that cover nearly all of his body. A control PET-CT revealed diffuse cutaneous involvement. CD20+, BCL2+, MUM1+, BCL6+ high grade B cell lymphoma infiltration was detected with skin biopsy. He was diagnosed as relapse lymphoma, so 2 cycles of R-DHAP were given. There was no treatment response; therefore, R-ICE regimen was started. The patient had achieved second complete remission and his skin lesions were completely regressed. The involvement of skin with CD20+ cells after 7 cycles of rituximab therapy favors that there is a rituximab resistant disease which tends to involve the skin. To conclude, DLBCL may relapse extensively with cutaneous involvement and the best treatment option in these patients is salvage chemotherapy followed by autologous peripheral blood stem cell transplantation. PMID:26457084

  17. [Chronic B-cell lymphoproliferative disorders with hairy cells].

    Science.gov (United States)

    Troussard, Xavier; Cornet, Édouard

    2015-01-01

    The standardized blood smear examination is the first step in the diagnosis of a B-cell chronic lymphoproliferative disorder and can guide further investigations. In the laboratory, the identification of hairy cells on blood smear is a matter of daily practice. Hairy cell proliferations represent heterogeneous entities and their respective diagnoses can be difficult. If hairy cell leukemia (HCL) and splenic marginal zone lymphoma (SMZL) represent separate entities, the variant form of HCL (HCLv) and splenic diffuse red pulp small B-cell lymphoma (SDRPL) remain provisional entities in the 2008 WHO classification. We discuss the main clinical and biological characteristics of these four entities and appropriate means to characterize, identify and distinguish from each other; standardized blood smear examination, multiparameter flow cytometry analysis, analysis of the repertoire of immunoglobulins heavy chains genes and their mutational status (mutated or unmutated profile), molecular analyses: BRAF gene V600E mutation in HCL and MAP2K1 gene mutations in HCLv. We also discuss the main therapeutic aspects with emphasis on the new targeted drugs that enter into force in the therapeutic arsenal. PMID:25858127

  18. Anticancer Effect of Curcumin on B Cell non- Hodgkin's Lymphoma

    Institute of Scientific and Technical Information of China (English)

    SUN Chunyan; LIU Xinyue; CHEN Yan; LIU Fang

    2005-01-01

    To explore the anticancer effect of curcumin on human B cell non-Hodgkin's lymphoma and compare its effects on human B cell non-Hodgkin's lymphoma cells and normal peripheral blood mononuclear cells (NPBMNCs). MTT assay was used to study the effect of curcumin on the growth of Raji cells and NPBMNCs. The effect of curcumin on the apoptosis of Raji cells and NPBMNC were studied by flow cytometry and TDT-mediated dUTP nick and labeling (TUNEL). The effect of curcumin on the cell cycle of Raji cells were examined by propidium iodide staining flow cytometry. The results showed that curcumin strongly inhibited ±1.82 μmol/L and curcumin induced Raji cell apoptosis in a time- and dose-dependent manner. Raji cells treated with curcumin showed curcumin did not demonstrate apparent proliferation inhibition and apoptosis induction in NPBMNCs. It was concluded that curcumin is able to inhibit the proliferation of Raji cells by regulating the cell cycle and inducing the cell apoptosis. Morever, curcumin has low toxicity on NPBMNCs but can selectively induce apoptosis in Raji cells.

  19. Polyclonal B-cell lymphocytosis with binucleated lymphocytes (PPBL

    Directory of Open Access Journals (Sweden)

    Xavier Troussard

    2008-10-01

    Full Text Available Xavier Troussard1, Edouard Cornet1, Jean-François Lesesve2, Carine Kourel3, Hossein Mossafa31Laboratoire d’Hématologie Côte de Nacre, Université Caen Basse Normandie Caen, Registre Régional des Hémopathies Malignes de Basse Normandie, France; 2Laboratoire d’Hématologie, Vandoeuvre-Les-Nancy Cedex, France; 3Département de Génétique Humaine, Laboratoire pasteur-Cerba, Cergy-Pontoise, FranceFor the Groupe Français d’Hématologie cellulaire (GFHCAbstract: Persistent polyclonal B-cell lymphocytosis (PPBL is a rare and recently described entity. The review of the literature show PPBL is diagnosed predominantly but not exclusively in women, usually smokers. PPBL is recognized by a moderate, chronic and absolute lymphocytosis (>4 × 109/l in the peripheral blood. In 10% of cases without lymphocytosis, the PPBL diagnosis has to be suggested by peripheral blood examination showing in all cases atypical binucleated lymphocytes. A polyclonal serum IgM is also associated and HLA-DR7 expression is present in most cases. Contrary to B-cell chronic lymphoproliferative disorders (B-CLPD, peripheral B cells are polyclonal with kappa and lambda light-chain expression and no clonal rearrangement of immunoglobulin heavy chain genes is usually demonstrated. The detection of an extra isochromosome for the long arm of chromosome 3 +i(3(q10 has to be considered as a specific marker of PPBL. We performed conventional cytogenetic analysis (CCA in 111 patients with typical PPBL we followed-up more than 4 years. +i(3q was detected in 34% (33/98, PCC in 8% (8/98 and both abnormalities in 31% (30/98. CCA showed neither +i(3q nor PCC in 28% (27/98. Fluorescence in situ hybridization (FISH was also performed in 84 cases and +i(3q was detected in 71% (60/84. When combining both procedures in 84 patients, +i(3q was detected in 17 patients with negative CCA and was confirmed in 43 patients with positive CCA. CCA and FISH were both negative in 24 cases. Whether

  20. A human antibody recognizing a conserved epitope of H5 hemagglutinin broadly neutralizes highly pathogenic avian influenza H5N1 viruses.

    Science.gov (United States)

    Hu, Hongxing; Voss, Jarrod; Zhang, Guoliang; Buchy, Philippi; Zuo, Teng; Wang, Lulan; Wang, Feng; Zhou, Fan; Wang, Guiqing; Tsai, Cheguo; Calder, Lesley; Gamblin, Steve J; Zhang, Linqi; Deubel, Vincent; Zhou, Boping; Skehel, John J; Zhou, Paul

    2012-03-01

    Influenza A virus infection is a persistent threat to public health worldwide due to its ability to evade immune surveillance through rapid genetic drift and shift. Current vaccines against influenza A virus provide immunity to viral isolates that are similar to vaccine strains. High-affinity neutralizing antibodies against conserved epitopes could provide immunity to diverse influenza virus strains and protection against future pandemic viruses. In this study, by using a highly sensitive H5N1 pseudotype-based neutralization assay to screen human monoclonal antibodies produced by memory B cells from an H5N1-infected individual and molecular cloning techniques, we developed three fully human monoclonal antibodies. Among them, antibody 65C6 exhibited potent neutralization activity against all H5 clades and subclades except for subclade 7.2 and prophylactic and therapeutic efficacy against highly pathogenic avian influenza H5N1 viruses in mice. Studies on hemagglutinin (HA)-antibody complexes by electron microscopy and epitope mapping indicate that antibody 65C6 binds to a conformational epitope comprising amino acid residues at positions 118, 121, 161, 164, and 167 (according to mature H5 numbering) on the tip of the membrane-distal globular domain of HA. Thus, we conclude that antibody 65C6 recognizes a neutralization epitope in the globular head of HA that is conserved among almost all divergent H5N1 influenza stains. PMID:22238297

  1. Separation of plasmacytoid dendritic cells from B-cell-biased lymphoid progenitor (BLP and Pre-pro B cells using PDCA-1.

    Directory of Open Access Journals (Sweden)

    Kay L Medina

    Full Text Available B-cell-biased lymphoid progenitors (BLPs and Pre-pro B cells lie at a critical juncture between B cell specification and commitment. However, both of these populations are heterogenous, which hampers investigation into the molecular changes that occur as lymphoid progenitors commit to the B cell lineage. Here, we demonstrate that there are PDCA-1(+Siglec H(+ plasmacytoid dendritic cells (pDCs that co-purify with BLPs and Pre-pro B cells, which express little or no CD11c or Ly6C. Removal of PDCA-1(+ pDCs separates B cell progenitors that express high levels of a Rag1-GFP reporter from Rag1-GFP(low/neg pDCs within the BLP and Pre-pro B populations. Analysis of Flt3-ligand knockout and IL-7Rα knockout mice revealed that there is a block in B cell development at the all-lymphoid progenitor (ALP stage, as the majority of cells within the BLP or Pre-pro B gates were PDCA-1(+ pDCs. Thus, removal of PDCA-1(+ pDCs is critical for analysis of BLP and Pre-pro B cell populations. Analysis of B cell potential within the B220(+CD19(- fraction demonstrated that AA4.1(+Ly6D(+PDCA-1(- Pre-pro B cells gave rise to CD19(+ B cells at high frequency, while PDCA-1(+ pDCs in this fraction did not. Interestingly, the presence of PDCA-1(+ pDCs within CLPs may help to explain the conflicting results regarding the origin of these cells.

  2. CD83 modulates B cell function in vitro: increased IL-10 and reduced Ig secretion by CD83Tg B cells.

    Directory of Open Access Journals (Sweden)

    Birte Kretschmer

    Full Text Available The murine transmembrane glycoprotein CD83 is an important regulator for both thymic T cell maturation and peripheral T cell responses. Recently, we reported that CD83 also has a function on B cells: Ubiquitous transgenic (Tg expression of CD83 interfered with the immunoglobulin (Ig response to infectious agents and to T cell dependent as well as T cell independent model antigen immunization. Here we compare the function of CD83Tg B cells that overexpress CD83 and CD83 mutant (CD83mu B cells that display a drastically reduced CD83 expression. Correlating with CD83 expression, the basic as well as the lipopolysaccharide (LPS induced expression of the activation markers CD86 and MHC-II are significantly increased in CD83Tg B cells and reciprocally decreased in CD83mu B cells. Wild-type B cells rapidly upregulate CD83 within three hours post BCR or TLR engagement by de novo protein synthesis. The forced premature overexpression of CD83 on the CD83Tg B cells results in reduced calcium signaling, reduced Ig secretion and a reciprocally increased IL-10 production upon in vitro activation. This altered phenotype is mediated by CD83 expressed on the B cells themselves, since it is observed in the absence of accessory cells. In line with this finding, purified CD83mu B cells displayed a reduced IL-10 production and slightly increased Ig secretion upon LPS stimulation in vitro. Taken together, our data strongly suggest that CD83 is expressed by B cells upon activation and contributes to the regulation of B cell function.

  3. Benchmarking of human resources management

    Directory of Open Access Journals (Sweden)

    David M. Akinnusi

    2008-12-01

    Full Text Available This paper reviews the role of human resource management (HRM which, today, plays a strategic partnership role in management. The focus of the paper is on HRM in the public sector, where much hope rests on HRM as a means of transforming the public service and achieving much needed service delivery. However, a critical evaluation of HRM practices in the public sector reveals that these services leave much to be desired. The paper suggests the adoption of benchmarking as a process to revamp HRM in the public sector so that it is able to deliver on its promises. It describes the nature and process of benchmarking and highlights the inherent difficulties in applying benchmarking in HRM. It concludes with some suggestions for a plan of action. The process of identifying “best” practices in HRM requires the best collaborative efforts of HRM practitioners and academicians. If used creatively, benchmarking has the potential to bring about radical and positive changes in HRM in the public sector. The adoption of the benchmarking process is, in itself, a litmus test of the extent to which HRM in the public sector has grown professionally.

  4. Benchmark simulation models, quo vadis?

    Science.gov (United States)

    Jeppsson, U; Alex, J; Batstone, D J; Benedetti, L; Comas, J; Copp, J B; Corominas, L; Flores-Alsina, X; Gernaey, K V; Nopens, I; Pons, M-N; Rodríguez-Roda, I; Rosen, C; Steyer, J-P; Vanrolleghem, P A; Volcke, E I P; Vrecko, D

    2013-01-01

    As the work of the IWA Task Group on Benchmarking of Control Strategies for wastewater treatment plants (WWTPs) is coming to an end, it is essential to disseminate the knowledge gained. For this reason, all authors of the IWA Scientific and Technical Report on benchmarking have come together to provide their insights, highlighting areas where knowledge may still be deficient and where new opportunities are emerging, and to propose potential avenues for future development and application of the general benchmarking framework and its associated tools. The paper focuses on the topics of temporal and spatial extension, process modifications within the WWTP, the realism of models, control strategy extensions and the potential for new evaluation tools within the existing benchmark system. We find that there are major opportunities for application within all of these areas, either from existing work already being done within the context of the benchmarking simulation models (BSMs) or applicable work in the wider literature. Of key importance is increasing capability, usability and transparency of the BSM package while avoiding unnecessary complexity.

  5. Epitope DNA vaccines against tuberculosis: spacers and ubiquitin modulates cellular immune responses elicited by epitope DNA vaccine

    Institute of Scientific and Technical Information of China (English)

    Wang QM; Sun SH; Hu ZL; Zhou FJ; Yin M; Xiao CJ; Zhang JC

    2005-01-01

    Cell-mediated immune responses are crucial in the protection against tuberculosis. In this study, we constructed epitope DNA vaccines (p3-M-38) encoding cytotoxic T lymphocyte (CTL) epitopes of MPT64 and 38 kDa proteins of Mycobacterium tuberculosis. In order to observe the influence of spacer sequence (Ala-Ala-Tyr) or ubiquitin (UbGR) on the efficacy of the two CTL epitopes, we also constructed DNA vaccines, p3-M-S(spacer)-38, p3-Ub (UbGR)-M-S-38 and p3-Ub-M-38. The immune responses elicited by the four DNA vaccines were tested in C57BL/6 (H-2b) mice. The cytotoxicity of T cells was detected by LDH-release method and by enzyme-linked immunospot assay for epitope-specific cells secreting interferon-gamma. The results showed that DNA immunization with p3-M-38 vaccine could induce epitope-specific CD8+ CTL response and that the spacer sequence (AAY) only enhanced M epitope presentation. The protein-targeting sequence (UbGR) enhanced the immunogenicity of the two epitopes. The finding that defined spacer sequences at C-terminus and protein-targeting degradation modulated the immune response of epitope string DNA vaccines will be of importance for the further development of multi-epitope DNA vaccines against tuberculosis.

  6. Performance Targets and External Benchmarking

    DEFF Research Database (Denmark)

    Friis, Ivar; Hansen, Allan; Vámosi, Tamás S.

    Research on relative performance measures, transfer pricing, beyond budgeting initiatives, target costing, piece rates systems and value based management has for decades underlined the importance of external benchmarking in performance management. Research conceptualises external benchmarking...... of the ‘inside’ costs of the sub-component, technical specifications of the product, opportunistic behavior from the suppliers and cognitive limitation. These are all aspects that easily can dismantle the market mechanism and make it counter-productive in the organization. Thus, by directing more attention...... as a market mechanism that can be brought inside the firm to provide incentives for continuous improvement and the development of competitive advances. However, whereas extant research primarily has focused on the importance and effects of using external benchmarks, less attention has been directed towards...

  7. Feasibility of Telomerase-Specific Adoptive T-cell Therapy for B-cell Chronic Lymphocytic Leukemia and Solid Malignancies.

    Science.gov (United States)

    Sandri, Sara; Bobisse, Sara; Moxley, Kelly; Lamolinara, Alessia; De Sanctis, Francesco; Boschi, Federico; Sbarbati, Andrea; Fracasso, Giulio; Ferrarini, Giovanna; Hendriks, Rudi W; Cavallini, Chiara; Scupoli, Maria Teresa; Sartoris, Silvia; Iezzi, Manuela; Nishimura, Michael I; Bronte, Vincenzo; Ugel, Stefano

    2016-05-01

    Telomerase (TERT) is overexpressed in 80% to 90% of primary tumors and contributes to sustaining the transformed phenotype. The identification of several TERT epitopes in tumor cells has elevated the status of TERT as a potential universal target for selective and broad adoptive immunotherapy. TERT-specific cytotoxic T lymphocytes (CTL) have been detected in the peripheral blood of B-cell chronic lymphocytic leukemia (B-CLL) patients, but display low functional avidity, which limits their clinical utility in adoptive cell transfer approaches. To overcome this key obstacle hindering effective immunotherapy, we isolated an HLA-A2-restricted T-cell receptor (TCR) with high avidity for human TERT from vaccinated HLA-A*0201 transgenic mice. Using several relevant humanized mouse models, we demonstrate that TCR-transduced T cells were able to control human B-CLL progression in vivo and limited tumor growth in several human, solid transplantable cancers. TERT-based adoptive immunotherapy selectively eliminated tumor cells, failed to trigger a self-MHC-restricted fratricide of T cells, and was associated with toxicity against mature granulocytes, but not toward human hematopoietic progenitors in humanized immune reconstituted mice. These data support the feasibility of TERT-based adoptive immunotherapy in clinical oncology, highlighting, for the first time, the possibility of utilizing a high-avidity TCR specific for human TERT. Cancer Res; 76(9); 2540-51. ©2016 AACR.

  8. B-cell exposure to self-antigen induces IL-10 producing B cells as well as IL-6- and TNF-α-producing B-cell subsets in healthy humans

    DEFF Research Database (Denmark)

    Langkjær, Anina; Kristensen, Birte; Hansen, Bjarke E;

    2012-01-01

    Human B cells are able to secrete IL-10 after stimulation with mitogens, but their ability to produce IL-10 and regulate T-cell responses after stimulation with self-antigens is unclear. We co-cultured thyroglobulin-pulsed B cells from healthy donors with autologous T cells and observed production...... of IL-10 and TGF-β, in addition to TNF-α and IL-6. Pulsing with foreign antigen, tetanus toxoid (TT), induced a Th1-response with minimal IL-10 production. After thyroglobulin-pulsing, 1.10±0.50% of B cells and 1.00±0.20% of CD4(+) T cells produced IL-10, compared to 0.29±0.19% of B cells (P=0.......01) and 0.13±0.15% of CD4(+) T cells (P=0.006) following TT-pulsing. Thyroglobulin-stimulated, IL-10-secreting B cells were enriched within CD5(+) and CD24(high) cells. While thyroglobulin-pulsed B cells induced only modest proliferation of CD4(+) T cells, B cells pulsed with TT induced vigorous...

  9. Intravascular Large B-Cell Lymphoma: A Difficult Diagnostic Challenge.

    Science.gov (United States)

    Khan, Maria S; McCubbin, Mark; Nand, Sucha

    2014-01-01

    Case Presentation. A 69-year-old Hispanic male, with a past history of diabetes and coronary disease, was admitted for fever, diarrhea, and confusion of 4 weeks duration. Physical examination showed a disoriented patient with multiple ecchymoses, possible ascites, and bilateral scrotal swelling. Hemoglobin was 6.7, prothrombin time (PT) 21.4 seconds with international normalized ratio 2.1, partial thromboplastin time (PTT) 55.6 seconds, fibrin split 10 µg/L, and lactate dehydrogenase (LDH) 1231 IU/L. Except for a positive DNA test for Epstein-Barr virus (EBV) infection, extensive diagnostic workup for infections, malignancy, or a neurological cause was negative. Mixing studies revealed a nonspecific inhibitor of PT and PTT but Factor VIII levels were normal. The patient was empirically treated with antibiotics but developed hypotension and died on day 27 of admission. At autopsy, patient was found to have intravascular diffuse large B-cell lymphoma involving skin, testes, lung, and muscles. The malignant cells were positive for CD20, CD791, Mum-1, and Pax-5 and negative for CD3, CD5, CD10, CD30, and Bcl-6. The malignant cells were 100% positive for Ki-67. Discussion. Intravascular large cell B-cell lymphoma (IVLBCL) is rare form of diffuse large B-cell lymphoma and tends to proliferate within small blood vessels, particularly capillaries and postcapillary venules. The cause of its affinity for vascular bed remains unknown. In many reports, IVLBCL was associated with HIV, HHV8, and EBV infections. The fact that our case showed evidence of EBV infection lends support to the association of this diagnosis to viral illness. The available literature on this subject is scant, and in many cases, the diagnosis was made only at autopsy. The typical presentation of this disorder is with B symptoms, progressive neurologic deficits, and skin findings. Bone marrow, spleen, and liver are involved in a minority of patients. Nearly all patients have elevated LDH, and about 65% are

  10. CEACAM1 induces B-cell survival and is essential for protective antiviral antibody production.

    Science.gov (United States)

    Khairnar, Vishal; Duhan, Vikas; Maney, Sathish Kumar; Honke, Nadine; Shaabani, Namir; Pandyra, Aleksandra A; Seifert, Marc; Pozdeev, Vitaly; Xu, Haifeng C; Sharma, Piyush; Baldin, Fabian; Marquardsen, Florian; Merches, Katja; Lang, Elisabeth; Kirschning, Carsten; Westendorf, Astrid M; Häussinger, Dieter; Lang, Florian; Dittmer, Ulf; Küppers, Ralf; Recher, Mike; Hardt, Cornelia; Scheffrahn, Inka; Beauchemin, Nicole; Göthert, Joachim R; Singer, Bernhard B; Lang, Philipp A; Lang, Karl S

    2015-01-01

    B cells are essential for antiviral immune defence because they produce neutralizing antibodies, present antigen and maintain the lymphoid architecture. Here we show that intrinsic signalling of CEACAM1 is essential for generating efficient B-cell responses. Although CEACAM1 exerts limited influence on the proliferation of B cells, expression of CEACAM1 induces survival of proliferating B cells via the BTK/Syk/NF-κB-axis. The absence of this signalling cascade in naive Ceacam1(-/-) mice limits the survival of B cells. During systemic infection with cytopathic vesicular stomatitis virus, Ceacam1(-/-) mice can barely induce neutralizing antibody responses and die early after infection. We find, therefore, that CEACAM1 is a crucial regulator of B-cell survival, influencing B-cell numbers and protective antiviral antibody responses. PMID:25692415

  11. Anti-B-Cell Therapies in Autoimmune Neurological Diseases: Rationale and Efficacy Trials.

    Science.gov (United States)

    Alexopoulos, Harry; Biba, Angie; Dalakas, Marinos C

    2016-01-01

    B cells have an ever-increasing role in the etiopathology of a number of autoimmune neurological disorders, acting as antibody-producing cells and, most importantly, as sensors, coordinators, and regulators of the immune response. B cells, among other functions, regulate the T-cell activation process through their participation in antigen presentation and production of cytokines. The availability of monoclonal antibodies or fusion proteins against B-cell surface molecules or B-cell trophic factors bestows a rational approach for treating autoimmune neurological disorders, even when T cells are the main effector cells. This review summarizes basic aspects of B-cell biology, discusses the role(s) of B cells in neurological autoimmunity, and presents anti-B-cell drugs that are either currently on the market or are expected to be available in the near future for treating neurological autoimmune disorders.

  12. Cutting Edge: Redox Signaling Hypersensitivity Distinguishes Human Germinal Center B Cells.

    Science.gov (United States)

    Polikowsky, Hannah G; Wogsland, Cara E; Diggins, Kirsten E; Huse, Kanutte; Irish, Jonathan M

    2015-08-15

    Differences in the quality of BCR signaling control key steps of B cell maturation and differentiation. Endogenously produced H2O2 is thought to fine tune the level of BCR signaling by reversibly inhibiting phosphatases. However, relatively little is known about how B cells at different stages sense and respond to such redox cues. In this study, we used phospho-specific flow cytometry and high-dimensional mass cytometry (CyTOF) to compare BCR signaling responses in mature human tonsillar B cells undergoing germinal center (GC) reactions. GC B cells, in contrast to mature naive B cells, memory B cells, and plasmablasts, were hypersensitive to a range of H2O2 concentrations and responded by phosphorylating SYK and other membrane-proximal BCR effectors in the absence of BCR engagement. These findings reveal that stage-specific redox responses distinguish human GC B cells. PMID:26157177

  13. Radiation Detection Computational Benchmark Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Shaver, Mark W.; Casella, Andrew M.; Wittman, Richard S.; McDonald, Ben S.

    2013-09-24

    Modeling forms an important component of radiation detection development, allowing for testing of new detector designs, evaluation of existing equipment against a wide variety of potential threat sources, and assessing operation performance of radiation detection systems. This can, however, result in large and complex scenarios which are time consuming to model. A variety of approaches to radiation transport modeling exist with complementary strengths and weaknesses for different problems. This variety of approaches, and the development of promising new tools (such as ORNL’s ADVANTG) which combine benefits of multiple approaches, illustrates the need for a means of evaluating or comparing different techniques for radiation detection problems. This report presents a set of 9 benchmark problems for comparing different types of radiation transport calculations, identifying appropriate tools for classes of problems, and testing and guiding the development of new methods. The benchmarks were drawn primarily from existing or previous calculations with a preference for scenarios which include experimental data, or otherwise have results with a high level of confidence, are non-sensitive, and represent problem sets of interest to NA-22. From a technical perspective, the benchmarks were chosen to span a range of difficulty and to include gamma transport, neutron transport, or both and represent different important physical processes and a range of sensitivity to angular or energy fidelity. Following benchmark identification, existing information about geometry, measurements, and previous calculations were assembled. Monte Carlo results (MCNP decks) were reviewed or created and re-run in order to attain accurate computational times and to verify agreement with experimental data, when present. Benchmark information was then conveyed to ORNL in order to guide testing and development of hybrid calculations. The results of those ADVANTG calculations were then sent to PNNL for

  14. Perceptual hashing algorithms benchmark suite

    Institute of Scientific and Technical Information of China (English)

    Zhang Hui; Schmucker Martin; Niu Xiamu

    2007-01-01

    Numerous perceptual hashing algorithms have been developed for identification and verification of multimedia objects in recent years. Many application schemes have been adopted for various commercial objects. Developers and users are looking for a benchmark tool to compare and evaluate their current algorithms or technologies. In this paper, a novel benchmark platform is presented. PHABS provides an open framework and lets its users define their own test strategy, perform tests, collect and analyze test data. With PHABS, various performance parameters of algorithms can be tested, and different algorithms or algorithms with different parameters can be evaluated and compared easily.

  15. Fully human broadly neutralizing monoclonal antibodies against influenza A viruses generated from the memory B cells of a 2009 pandemic H1N1 influenza vaccine recipient

    International Nuclear Information System (INIS)

    Whether the 2009 pandemic H1N1 influenza vaccine can induce heterosubtypic cross-protective anti-hemagglutinin (HA) neutralizing antibodies is an important issue. We obtained a panel of fully human monoclonal antibodies from the memory B cells of a 2009 pandemic H1N1 influenza vaccine recipient. Most of the monoclonal antibodies targeted the HA protein but not the HA1 fragment. Among the analyzed antibodies, seven mAbs exhibited neutralizing activity against several influenza A viruses of different subtypes. The conserved linear epitope targeted by the neutralizing mAbs (FIEGGWTGMVDGWYGYHH) is part of the fusion peptide on HA2. Our work suggests that a heterosubtypic neutralizing antibody response primarily targeting the HA stem region exists in recipients of the 2009 pandemic H1N1 influenza vaccine. The HA stem region contains various conserved neutralizing epitopes with the fusion peptide as an important one. This work may aid in the design of a universal influenza A virus vaccine.

  16. Fully human broadly neutralizing monoclonal antibodies against influenza A viruses generated from the memory B cells of a 2009 pandemic H1N1 influenza vaccine recipient

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Weibin [Molecular Virus Unit, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200025 (China); Chen, Aizhong [Key Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China); Miao, Yi [Shanghai Xuhui Central Hospital, Shanghai 200031 (China); Xia, Shengli [Center for Disease Control and Prevention of Henan Province, Zhengzhou 450016 (China); Ling, Zhiyang; Xu, Ke; Wang, Tongyan [Molecular Virus Unit, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200025 (China); Xu, Ying; Cui, Jun; Wu, Hongqiang; Hu, Guiyu; Tian, Lin; Wang, Lingling [Key Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China); Shu, Yuelong [Chinese Center for Disease Control and Prevention, Beijing 102206 (China); Ma, Xiaowei [Hualan Biological Bacterin Company, Xinxiang 453003 (China); Xu, Bianli; Zhang, Jin [Center for Disease Control and Prevention of Henan Province, Zhengzhou 450016 (China); Lin, Xiaojun, E-mail: linxiaojun@hualan.com [Hualan Biological Bacterin Company, Xinxiang 453003 (China); Bian, Chao, E-mail: cbian@sibs.ac.cn [Key Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China); Sun, Bing, E-mail: bsun@sibs.ac.cn [Molecular Virus Unit, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200025 (China); Key Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031 (China)

    2013-01-20

    Whether the 2009 pandemic H1N1 influenza vaccine can induce heterosubtypic cross-protective anti-hemagglutinin (HA) neutralizing antibodies is an important issue. We obtained a panel of fully human monoclonal antibodies from the memory B cells of a 2009 pandemic H1N1 influenza vaccine recipient. Most of the monoclonal antibodies targeted the HA protein but not the HA1 fragment. Among the analyzed antibodies, seven mAbs exhibited neutralizing activity against several influenza A viruses of different subtypes. The conserved linear epitope targeted by the neutralizing mAbs (FIEGGWTGMVDGWYGYHH) is part of the fusion peptide on HA2. Our work suggests that a heterosubtypic neutralizing antibody response primarily targeting the HA stem region exists in recipients of the 2009 pandemic H1N1 influenza vaccine. The HA stem region contains various conserved neutralizing epitopes with the fusion peptide as an important one. This work may aid in the design of a universal influenza A virus vaccine.

  17. B Cell Depletion: Rituximab in Glomerular Disease and Transplantation

    Directory of Open Access Journals (Sweden)

    S. Marinaki

    2013-12-01

    Full Text Available B cells play a central role in the pathogenesis of many autoimmune diseases. Selective targeting can be achieved with the use of the monoclonal antibody rituximab. In addition to being a drug for non-Hodgkin's lymphoma, rituximab is also an FDA-approved treatment for refractory rheumatoid arthritis and, since recently, ANCA vasculitis. It has shown efficacy in many autoimmune diseases. This review will discuss current evidence and the rationale of the use of rituximab in glomerular diseases, including randomized controlled trials. The focus will be on the use of rituximab in idiopathic membranous nephropathy, systemic lupus erythematosus and ANCA-associated vasculitis. The emerging role of rituximab in renal transplantation, where it seems to be important for the desensitization protocols for highly sensitized patients as well as for the preconditioning of ABO-incompatible recipients and the treatment of antibody-mediated rejection, will also be addressed.

  18. Diffuse Large B Cell Lymphoma of the Breast

    Directory of Open Access Journals (Sweden)

    Feryal Karaca

    2015-03-01

    Full Text Available Primary breast lymphoma is rarely encountered in Non-Hodgkin Lymphomas. However, if early diagnosis is made, and treatment is started immediately in patients with low grade and stage, patient survival is increased. 39-year old female patient applied us due to a palpable mass. She was diagnosed with the Non-Hodgkin Lymphoma Diffuse Large B Cell Lymphoma after the investigations. Curative external radiotherapy was applied after 6 courses of CHOP-R chemotherapy to the patient with Stage-IIE favorable, and B symptoms. After 48-month follow up, patient follow up is being continued without any progression, or recurrence or metastasis. [Cukurova Med J 2015; 40(1.000: 151-157

  19. T-cell leukemia 1 expression in nodal Epstein-Barr virus-negative diffuse large B-cell lymphoma and primary mediastinal B-cell lymphoma.

    Science.gov (United States)

    Gualco, Gabriela; Weiss, Lawrence M; Barber, Glen N; Bacchi, Carlos E

    2010-09-01

    The physiologic expression of the product of the proto-oncogene TCL1 (T-cell leukemia 1) is primarily restricted to early embryonic cells. In nonneoplastic B cells, the expression of TCL1 is determined by the differentiation step with silencing at the germinal center stage. TCL1 protein is overexpressed in a wide variety of human diseases. It has been shown that TCL1 is a powerful B-cell oncogene, which has been implicated in the pathogenesis of various types of mature B-cell lymphomas. There is no comparative information in the literature addressing the expression of TCL1 in pediatric and adult nodal diffuse large B-cell lymphoma or primary mediastinal large B-cell lymphoma. We studied 55 cases of adult and pediatric diffuse large B-cell lymphoma and primary mediastinal large B-cell lymphoma to analyze the phenotypic profile of these lymphomas, including TCL1 expression, and its relationship with clinical outcome in different age groups. The cases were analyzed by immunohistochemistry for the expression of TCL1, CD10, BCL-2, BCL-6, and MUM1. We also evaluated c-MYC translocation by fluorescence in situ hybridization. TCL1 was observed in 11 cases, 5 pediatric and 6 adult cases, all but one diffuse large B-cell lymphoma. Pediatric cases showed a significant association between TCL1 expression, high proliferative index, and presence of c-MYC translocation. TCL1 positivity was predominantly found in germinal center phenotype diffuse large B-cell lymphoma. Overall survival was worse in adult TCL1-positive cases than pediatric ones. Primary mediastinal large B-cell lymphomas infrequently expressed TCL1 in both age groups.

  20. A xylogalacturonan epitope is specifically associated with plant cell detachment

    DEFF Research Database (Denmark)

    Willats, William George Tycho; McCartney, L.; Steele-King, C.G.;

    2004-01-01

    A monoclonal antibody (LM8) was generated with specificity for xyloglacturonan (XGA) isolated from pea (Pisum sativum L.) testae. Characterization of the LM8 epitope indicates that it is a region of XGA that is highly substituted with xylose. Immunocytochemical analysis indicates that this epitop...

  1. Immune epitope database analysis resource (IEDB-AR)

    DEFF Research Database (Denmark)

    Zhang, Qing; Wang, Peng; Kim, Yohan;

    2008-01-01

    We present a new release of the immune epitope database analysis resource (IEDB-AR, http://tools.immuneepitope.org), a repository of web-based tools for the prediction and analysis of immune epitopes. New functionalities have been added to most of the previously implemented tools, and a total...

  2. High epitope expression levels increase competition between T cells.

    Directory of Open Access Journals (Sweden)

    Almut Scherer

    2006-08-01

    Full Text Available Both theoretical predictions and experimental findings suggest that T cell populations can compete with each other. There is some debate on whether T cells compete for aspecific stimuli, such as access to the surface on antigen-presenting cells (APCs or for specific stimuli, such as their cognate epitope ligand. We have developed an individual-based computer simulation model to study T cell competition. Our model shows that the expression level of foreign epitopes per APC determines whether T cell competition is mainly for specific or aspecific stimuli. Under low epitope expression, competition is mainly for the specific epitope stimuli, and, hence, different epitope-specific T cell populations coexist readily. However, if epitope expression levels are high, aspecific competition becomes more important. Such between-specificity competition can lead to competitive exclusion between different epitope-specific T cell populations. Our model allows us to delineate the circumstances that facilitate coexistence of T cells of different epitope specificity. Understanding mechanisms of T cell coexistence has important practical implications for immune therapies that require a broad immune response.

  3. Autoantibody recognition mechanisms of p53 epitopes

    Science.gov (United States)

    Phillips, J. C.

    2016-06-01

    There is an urgent need for economical blood based, noninvasive molecular biomarkers to assist in the detection and diagnosis of cancers in a cost-effective manner at an early stage, when curative interventions are still possible. Serum autoantibodies are attractive biomarkers for early cancer detection, but their development has been hindered by the punctuated genetic nature of the ten million known cancer mutations. A landmark study of 50,000 patients (Pedersen et al., 2013) showed that a few p53 15-mer epitopes are much more sensitive colon cancer biomarkers than p53, which in turn is a more sensitive cancer biomarker than any other protein. The function of p53 as a nearly universal "tumor suppressor" is well established, because of its strong immunogenicity in terms of not only antibody recruitment, but also stimulation of autoantibodies. Here we examine dimensionally compressed bioinformatic fractal scaling analysis for identifying the few sensitive epitopes from the p53 amino acid sequence, and show how it could be used for early cancer detection (ECD). We trim 15-mers to 7-mers, and identify specific 7-mers from other species that could be more sensitive to aggressive human cancers, such as liver cancer. Our results could provide a roadmap for ECD.

  4. Nominal GDP: Target or Benchmark?

    OpenAIRE

    Hetzel, Robert L.

    2015-01-01

    Some observers have argued that the Federal Reserve would best fulfill its mandate by adopting a target for nominal gross domestic product (GDP). Insights from the monetarist tradition suggest that nominal GDP targeting could be destabilizing. However, adopting benchmarks for both nominal and real GDP could offer useful information about when monetary policy is too tight or too loose.

  5. Benchmark calculations for EGS5

    International Nuclear Information System (INIS)

    In the past few years, EGS4 has undergone an extensive upgrade to EGS5, in particularly in the areas of low-energy electron physics, low-energy photon physics, PEGS cross section generation, and the coding from Mortran to Fortran programming. Benchmark calculations have been made to assure the accuracy, reliability and high quality of the EGS5 code system. This study reports three benchmark examples that show the successful upgrade from EGS4 to EGS5 based on the excellent agreements among EGS4, EGS5 and measurements. The first benchmark example is the 1969 Crannell Experiment to measure the three-dimensional distribution of energy deposition for 1-GeV electrons shower in water and aluminum tanks. The second example is the 1995 Compton-scattered spectra measurements for 20-40 keV, linearly polarized photon by Namito et. al., in KEK, which was a main part of the low-energy photon expansion work for both EGS4 and EGS5. The third example is the 1986 heterogeneity benchmark experiment by Shortt et. al., who used a monoenergetic 20-MeV electron beam to hit the front face of a water tank containing both air and aluminum cylinders and measured spatial depth dose distribution using a small solid-state detector. (author)

  6. PRISMATIC CORE COUPLED TRANSIENT BENCHMARK

    Energy Technology Data Exchange (ETDEWEB)

    J. Ortensi; M.A. Pope; G. Strydom; R.S. Sen; M.D. DeHart; H.D. Gougar; C. Ellis; A. Baxter; V. Seker; T.J. Downar; K. Vierow; K. Ivanov

    2011-06-01

    The Prismatic Modular Reactor (PMR) is one of the High Temperature Reactor (HTR) design concepts that have existed for some time. Several prismatic units have operated in the world (DRAGON, Fort St. Vrain, Peach Bottom) and one unit is still in operation (HTTR). The deterministic neutronics and thermal-fluids transient analysis tools and methods currently available for the design and analysis of PMRs have lagged behind the state of the art compared to LWR reactor technologies. This has motivated the development of more accurate and efficient tools for the design and safety evaluations of the PMR. In addition to the work invested in new methods, it is essential to develop appropriate benchmarks to verify and validate the new methods in computer codes. The purpose of this benchmark is to establish a well-defined problem, based on a common given set of data, to compare methods and tools in core simulation and thermal hydraulics analysis with a specific focus on transient events. The benchmark-working group is currently seeking OECD/NEA sponsorship. This benchmark is being pursued and is heavily based on the success of the PBMR-400 exercise.

  7. Benchmarking biodiversity performances of farmers

    NARCIS (Netherlands)

    Snoo, de G.R.; Lokhorst, A.M.; Dijk, van J.; Staats, H.; Musters, C.J.M.

    2010-01-01

    Farmers are the key players when it comes to the enhancement of farmland biodiversity. In this study, a benchmark system that focuses on improving farmers’ nature conservation was developed and tested among Dutch arable farmers in different social settings. The results show that especially tailored

  8. Benchmarked Library Websites Comparative Study

    KAUST Repository

    Ramli, Rindra M.

    2015-01-01

    This presentation provides an analysis of services provided by the benchmarked library websites. The exploratory study includes comparison of these websites against a list of criterion and presents a list of services that are most commonly deployed by the selected websites. In addition to that, the investigators proposed a list of services that could be provided via the KAUST library website.

  9. Benchmarking Universiteitsvastgoed: Managementinformatie bij vastgoedbeslissingen

    NARCIS (Netherlands)

    Den Heijer, A.C.; De Vries, J.C.

    2004-01-01

    Voor u ligt het eindrapport van het onderzoek "Benchmarking universiteitsvastgoed". Dit rapport is de samenvoeging van twee deel producten: het theorierapport (verschenen in december 2003) en het praktijkrapport (verschenen in januari 2004). Onderwerpen in het theoriedeel zijn de analyse van andere

  10. SAP modulates B cell functions in a genetic background-dependent manner.

    Science.gov (United States)

    Detre, Cynthia; Yigit, Burcu; Keszei, Marton; Castro, Wilson; Magelky, Erica M; Terhorst, Cox

    2013-06-01

    Mutations affecting the SLAM-associated protein (SAP) are responsible for the X-linked lympho-proliferative syndrome (XLP), a severe primary immunodeficiency syndrome with disease manifestations that include fatal mononucleosis, B cell lymphoma and dysgammaglobulinemia. It is well accepted that insufficient help by SAP-/- CD4+ T cells, in particular during the germinal center reaction, is a component of dysgammaglobulinemia in XLP patients and SAP-/- animals. It is however not well understood whether in XLP patients and SAP-/- mice B cell functions are affected, even though B cells themselves do not express SAP. Here we report that B cell intrinsic responses to haptenated protein antigens are impaired in SAP-/- mice and in Rag-/- mice into which B cells derived from SAP-/- mice together with wt CD4+ T cells had been transferred. This impaired B cells functions are in part depending on the genetic background of the SAP-/- mouse, which affects B cell homeostasis. Surprisingly, stimulation with an agonistic anti-CD40 causes strong in vivo and in vitro B cell responses in SAP-/- mice. Taken together, the data demonstrate that genetic factors play an important role in the SAP-related B cell functions. The finding that anti-CD40 can in part restore impaired B cell responses in SAP-/- mice, suggests potentially novel therapeutic interventions in subsets of XLP patients.

  11. Natalizumab treatment leads to an increase in circulating CXCR3-expressing B cells

    Science.gov (United States)

    Penttilä, Tarja-Leena; Airas, Laura

    2016-01-01

    Objective: To study the effects of natalizumab treatment on subgroups of circulating peripheral blood B cell populations. Methods: We studied the proportions and absolute numbers of CD19+CD20+, CD10+, and CD5+ B cell populations, and determined very late activation antigen-4 and chemokine receptor CXCR3, CCR5, and CCR6 expression on B cells in the peripheral blood of 14 natalizumab-treated patients with relapsing-remitting multiple sclerosis. Five blood samples per patient were obtained longitudinally before and during the first year of treatment. Blood samples were analyzed by 6-color flow cytometry. Results: Proportions of B cells and CD10+ pre–B cells were significantly increased, and very late activation antigen-4 expression on the B cell surface was significantly decreased already after 1 week of natalizumab treatment. Natalizumab-induced sustained increase in the proportion and absolute number of CXCR3-expressing B cells was statistically significant after 1 month of treatment. There were no changes in the proportions of CCR5- or CCR6-expressing B cells. Conclusions: The rapid and persistent increase in circulating CXCR3-expressing B cells in response to natalizumab treatment possibly reflects the relevance of this chemokine receptor in controlling migration of B cells into the CNS in humans in vivo. PMID:27800533

  12. Splenectomy associated changes in IgM memory B cells in an adult spleen registry cohort.

    Directory of Open Access Journals (Sweden)

    Paul U Cameron

    Full Text Available Asplenic patients have a lifelong risk of overwhelming post-splenectomy infection and have been reported to have low numbers of peripheral blood IgM memory B cells. The clinical value of quantitation of memory B cells as an indicator of splenic abnormality or risk of infection has been unclear. To assess changes in B cell sub-populations after splenectomy we studied patients recruited to a spleen registry (n = 591. A subset of 209 adult asplenic or hyposplenic subjects, and normal controls (n = 140 were tested for IgM memory B cells. We also determined a changes in IgM memory B cells with time after splenectomy using the cross-sectional data from patients on the registry and b the kinetics of changes in haematological markers associated with splenectomy(n = 45. Total B cells in splenectomy patients did not differ from controls, but memory B cells, IgM memory B cells and switched B cells were significantly (p<0.001 reduced. The reduction was similar for different indications for splenectomy. Changes of asplenia in routine blood films including presence of Howell-Jolly bodies (HJB, occurred early (median 25 days and splenectomy associated thrombocytosis and lymphocytosis peaked by 50 days. There was a more gradual decrease in IgM memory B cells reaching a stable level within 6 months after splenectomy. IgM memory B cells as proportion of B cells was the best discriminator between splenectomized patients and normal controls and at the optimal cut-off of 4.53, showed a true positive rate of 95% and false positive rate of 20%. In a survey of 152 registry patients stratified by IgM memory B cells around this cut-off there was no association with minor infections and no registry patients experienced OPSI during the study. Despite significant changes after splenectomy, conventional measures of IgM memory cells have limited clinical utility in this population.

  13. Naïve and memory B cells exhibit distinct biochemical responses following BCR engagement.

    Science.gov (United States)

    Moens, Leen; Kane, Alisa; Tangye, Stuart G

    2016-09-01

    Immunological memory is characterized by the rapid reactivation of memory B cells that produce large quantities of high-affinity antigen-specific antibodies. This contrasts the response of naïve B cells, and the primary immune response, which is much slower and of lower affinity. Memory responses are critical for protection against infectious diseases and form the basis of most currently available vaccines. Although we have known about the phenomenon of long-lived memory for centuries, the biochemical differences underlying these diverse responses of naïve and memory B cells is incompletely resolved. Here we investigated the nature of B-cell receptor (BCR) signaling in human splenic naïve, IgM(+) memory and isotype-switched memory B cells following multivalent BCR crosslinking. We observed comparable rapid and transient phosphorylation kinetics for proximal (phosphotyrosine and spleen tyrosine kinase) and propagation (B-cell linker, phospholipase Cγ2) signaling components in these different B-cell subsets. However, the magnitude of activation of downstream components of the BCR signaling pathway were greater in memory compared with naïve cells. Although no differences were observed in the magnitude of Ca(2+) mobilization between subsets, IgM(+) memory B cells exhibited a more rapid Ca(2+) mobilization and a greater depletion of the Ca(2+) endoplasmic reticulum stores, while IgG(+) memory B cells had a prolonged Ca(2+) uptake. Collectively, our findings show that intrinsic signaling features of B-cell subsets contribute to the robust response of human memory B cells over naïve B cells. This has implications for our understanding of memory B-cell responses and provides a framework to modulate these responses in the setting of vaccination and immunopathologies, such as immunodeficiency and autoimmunity. PMID:27101923

  14. 42 CFR 440.385 - Delivery of benchmark and benchmark-equivalent coverage through managed care entities.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Delivery of benchmark and benchmark-equivalent...: GENERAL PROVISIONS Benchmark Benefit and Benchmark-Equivalent Coverage § 440.385 Delivery of benchmark and benchmark-equivalent coverage through managed care entities. In implementing benchmark or...

  15. CD19 CAR-targeted T cells induce long-term remission and B Cell Aplasia in an immunocompetent mouse model of B cell acute lymphoblastic leukemia.

    Directory of Open Access Journals (Sweden)

    Marco L Davila

    Full Text Available Although many adults with B cell acute lymphoblastic leukemia (B-ALL are induced into remission, most will relapse, underscoring the dire need for novel therapies for this disease. We developed murine CD19-specific chimeric antigen receptors (CARs and an immunocompetent mouse model of B-ALL that recapitulates the disease at genetic, cellular, and pathologic levels. Mouse T cells transduced with an all-murine CD3ζ/CD28-based CAR that is equivalent to the one being used in our clinical trials, eradicate B-ALL in mice and mediate long-term B cell aplasias. In this model, we find that increasing conditioning chemotherapy increases tumor eradication, B cell aplasia, and CAR-modified T cell persistence. Quantification of recipient B lineage cells allowed us to estimate an in vivo effector to endogenous target ratio for B cell aplasia maintenance. In mice exhibiting a dramatic B cell reduction we identified a small population of progenitor B cells in the bone marrow that may serve as a reservoir for long-term CAR-modified T cell stimulation. Lastly, we determine that infusion of CD8+ CAR-modified T cells alone is sufficient to maintain long-term B cell eradication. The mouse model we report here should prove valuable for investigating CAR-based and other therapies for adult B-ALL.

  16. TGFβ activated kinase 1 (TAK1 at the crossroad of B cell receptor and Toll-like receptor 9 signaling pathways in human B cells.

    Directory of Open Access Journals (Sweden)

    Dániel Szili

    Full Text Available B cell development and activation are regulated by combined signals mediated by the B cell receptor (BCR, receptors for the B-cell activating factor of the tumor necrosis factor family (BAFF-R and the innate receptor, Toll-like receptor 9 (TLR9. However, the underlying mechanisms by which these signals cooperate in human B cells remain unclear. Our aim was to elucidate the key signaling molecules at the crossroads of BCR, BAFF-R and TLR9 mediated pathways and to follow the functional consequences of costimulation.Therefore we stimulated purified human B cells by combinations of anti-Ig, B-cell activating factor of the tumor necrosis factor family (BAFF and the TLR9 agonist, CpG oligodeoxynucleotide. Phosphorylation status of various signaling molecules, B cell proliferation, cytokine secretion, plasma blast generation and the frequency of IgG producing cells were investigated. We have found that BCR induced signals cooperate with BAFF-R- and TLR9-mediated signals at different levels of cell activation. BCR and BAFF- as well as TLR9 and BAFF-mediated signals cooperate at NFκB activation, while BCR and TLR9 synergistically costimulate mitogen activated protein kinases (MAPKs, ERK, JNK and p38. We show here for the first time that the MAP3K7 (TGF beta activated kinase, TAK1 is responsible for the synergistic costimulation of B cells by BCR and TLR9, resulting in an enhanced cell proliferation, plasma blast generation, cytokine and antibody production. Specific inhibitor of TAK1 as well as knocking down TAK1 by siRNA abrogates the synergistic signals. We conclude that TAK1 is a key regulator of receptor crosstalk between BCR and TLR9, thus plays a critical role in B cell development and activation.

  17. Accumulation of self-reactive naive and memory B cell reveals sequential defects in B cell tolerance checkpoints in Sjogren's syndrome.

    Directory of Open Access Journals (Sweden)

    Elisa Corsiero

    Full Text Available Sjögren's syndrome (SS is an autoimmune disease characterised by breach of self-tolerance towards nuclear antigens resulting in high affinity circulating autoantibodies. Although peripheral B cell disturbances have been described in SS, with predominance of naïve and reduction of memory B cells, the stage at which errors in B cell tolerance checkpoints accumulate in SS is unknown. Here we determined the frequency of self- and poly-reactive B cells in the circulating naïve and memory compartment of SS patients. Single CD27-IgD+ naïve, CD27+IgD+ memory unswitched and CD27+IgD- memory switched B cells were sorted by FACS from the peripheral blood of 7 SS patients. To detect the frequency of polyreactive and autoreactive clones, paired Ig VH and VL genes were amplified, cloned and expressed as recombinant monoclonal antibodies (rmAbs displaying identical specificity of the original B cells. IgVH and VL gene usage and immunoreactivity of SS rmAbs were compared with those obtained from healthy donors (HD. From a total of 353 VH and 293 VL individual sequences, we obtained 114 rmAbs from circulating naïve (n = 66 and memory (n = 48 B cells of SS patients. Analysis of the Ig V gene repertoire did not show significant differences in SS vs. HD B cells. In SS patients, circulating naïve B cells (with germline VH and VL genes displayed a significant accumulation of clones autoreactive against Hep-2 cells compared to HD (43.1% vs. 25%. Moreover, we demonstrated a progressive increase in the frequency of circulating anti-nuclear naïve (9.3%, memory unswitched (22.2% and memory switched (27.3% B cells in SS patients. Overall, these data provide novel evidence supporting the existence of both early and late defects in B cell tolerance checkpoints in patients with SS resulting in the accumulation of autoreactive naïve and memory B cells.

  18. Cbl Suppresses B Cell Receptor–Mediated Phospholipase C (Plc)-γ2 Activation by Regulating B Cell Linker Protein–Plc-γ2 Binding

    OpenAIRE

    Yasuda, Tomoharu; Maeda, Akito; Kurosaki, Mari; Tezuka, Tohru; Hironaka, Katsunori; Yamamoto, Tadashi; Kurosaki, Tomohiro

    2000-01-01

    Accumulating evidence indicates that the Cbl protein plays a negative role in immune receptor signaling; however, the mode of Cbl action in B cell receptor (BCR) signaling still remains unclear. DT40 B cells deficient in Cbl showed enhanced BCR-mediated phospholipase C (PLC)-γ2 activation, thereby leading to increased apoptosis. A possible explanation for the involvement of Cbl in PLC-γ2 activation was provided by findings that Cbl interacts via its Src homology 2 (SH2) domain with B cell lin...

  19. MYC Negative Rectal B-Cell Lymphoma, Unclassifiable, with Features Intermediate between Diffuse Large B-Cell Lymphoma and Burkitt’s Lymphoma in an Immunocompetent Patient

    OpenAIRE

    Parikh, Jignesh G.; Ted Strom; Ilya Stone

    2013-01-01

    B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt’s lymphoma (BLUI) is a recently added entity to the World Health Organization (WHO) classification to address a grey zone between large B-cell lymphoma (DLBCL) and Burkitt’s lymphoma (BL). These are rare aggressive lymphomas, which were previously also known as Burkitt’s-like lymphoma (BLL). BL and BLUI/BLL of the colon mostly involve the ileocecal region. In the rectum, BL and BLUI/B...

  20. Signaling Proteins and Transcription Factors in Normal and Malignant Early B Cell Development

    Directory of Open Access Journals (Sweden)

    Patricia Pérez-Vera

    2011-01-01

    Full Text Available B cell development starts in bone marrow with the commitment of hematopoietic progenitors to the B cell lineage. In murine models, the IL-7 and preBCR receptors, and the signaling pathways and transcription factors that they regulate, control commitment and maintenance along the B cell pathway. E2A, EBF1, PAX5, and Ikaros are among the most important transcription factors controlling early development and thereby conditioning mice homeostatic B cell lymphopoiesis. Importantly, their gain or loss of function often results in malignant development in humans, supporting conserved roles for these transcription factors. B cell acute lymphoblastic leukemia is the most common cause of pediatric cancer, and it is characterized by unpaired early B cell development resulting from genetic lesions in these critical signaling pathways and transcription factors. Fine mapping of these genetic abnormalities is allowing more specific treatments, more accurately predicting risk profiles for this disease, and improving survival rates.

  1. Human B cells produce chemokine CXCL10 in the presence of Mycobacterium tuberculosis specific T cells

    DEFF Research Database (Denmark)

    Hoff, Soren T; Salman, Ahmed M; Ruhwald, Morten;

    2015-01-01

    BACKGROUND: The role of B cells in human host response to Mycobacterium tuberculosis (Mtb) infection is still controversial, but recent evidence suggest that B cell follicle like structures within the lung may influence host responses through regulation of the local cytokine environment. A candid......BACKGROUND: The role of B cells in human host response to Mycobacterium tuberculosis (Mtb) infection is still controversial, but recent evidence suggest that B cell follicle like structures within the lung may influence host responses through regulation of the local cytokine environment...... appeared to be mediated via IFN-γ and dependent on contact with antigen-specific T cells recognizing the antigen. CONCLUSION: Human B cells are able to produce CXCL10 in an IFN-γ and T cell contact-dependent manner. The present findings suggest a possible mechanism through which B cells in part may...

  2. Microbial Translocation and B Cell Dysfunction in Human Immunodeficiency Virus Disease

    Directory of Open Access Journals (Sweden)

    Wei Jiang

    2012-01-01

    Full Text Available The gut mucosal barrier disrupted in HIV disease, resulting in increased systemic exposure to microbial products such as Lipo Polys Accharide (LPS. The association of enhanced microbial translocation and B cell dysfunction in HIV disease is not fully understood. High dose and short term exposure of microbial Toll-Like Receptor (TLR agonists were used as vaccine adjuvants, however, low dose and long term exposure of TLR agonists could be harmful. The characteristics of B cell dysfunction in HIV disease included B cell, especially memory B cell depletion, enhanced levels of autoimmune antibodies and impaired vaccine or antigen responsiveness. This review discusses and explores the possibility of the effect of microbial translocation on memory B cell depletion and impaired vaccine responses in HIV infection. By determining the mechanisms of B cell depletion and perturbations in HIV disease, it may be possible to design interventions that can improve immune responses to vaccines, reduce selected opportunistic infections and perhaps slow disease progression.

  3. Tourism Destination Benchmarking: Evaluation and Selection of the Benchmarking Partners

    Directory of Open Access Journals (Sweden)

    Luštický Martin

    2012-03-01

    Full Text Available Tourism development has an irreplaceable role in regional policy of almost all countries. This is due to its undeniable benefits for the local population with regards to the economic, social and environmental sphere. Tourist destinations compete for visitors at tourism market and subsequently get into a relatively sharp competitive struggle. The main goal of regional governments and destination management institutions is to succeed in this struggle by increasing the competitiveness of their destination. The quality of strategic planning and final strategies is a key factor of competitiveness. Even though the tourism sector is not the typical field where the benchmarking methods are widely used, such approaches could be successfully applied. The paper focuses on key phases of the benchmarking process which lies in the search for suitable referencing partners. The partners are consequently selected to meet general requirements to ensure the quality if strategies. Following from this, some specific characteristics are developed according to the SMART approach. The paper tests this procedure with an expert evaluation of eight selected regional tourism strategies of regions in the Czech Republic, Slovakia and Great Britain. In this way it validates the selected criteria in the frame of the international environment. Hence, it makes it possible to find strengths and weaknesses of selected strategies and at the same time facilitates the discovery of suitable benchmarking partners.

  4. Conserved regions ofPlasmodium vivax potential vaccine candidate antigens in Sri Lanka:Consciousin silico analysis of prospective conformational epitope regions

    Institute of Scientific and Technical Information of China (English)

    Shanika Amarasinghe; Hashendra Kathriarachchi; Preethi Udagama

    2014-01-01

    Objective:To do mapping and modeling of conformationalB cell epitope regions of highly conserved and protective regions of three merozoitecandidate vaccine proteins ofPlasmodium vivax(P. vivax) ,ie. merozoite purface protein-1(PvMSP-1), apical membrane antigen -1 domainⅡ(PvAMA1-DⅡ) and regionⅡ of theDuffy binding protein(PvDBPⅡ), and to analyze the immunogenic properties of these predicted epitopes.Methods:3-D structures of amino acid haplotypes fromSriLanka(available inGeneBank) ofPvMSP-119(n=27),PvAMA1-DⅡ(n=21) andPvDBPⅡ(n=33) were modeled.SEPPA, selected as the best online server was used for conformational epitope predictions, while prediction and modeling of protein structure and properties related to immunogenicity was carried out withGeno3D server,SCRATCHProtein Server,NetSurfPServer and standalonesoftware,Genious5.4.4.Results:SEPPA revealed that regions of predicted conformational epitopes formed4 clusters inPvMSP-I19, and3 clusters each inPvAMA1-DⅡ andPvDBPⅡ, all of which displayed a high degree of hydrophilicity, contained solvent exposed residues, displayed high probability of antigenicity and showed positive antigenic propensity values, that indicated high degree of immunogenicity.Conclusions:Findings of this study revealed and confirmed that different parts of the sequences of each of the conserved regions of the three selected potential vaccine candidate antigens ofP. vivax are important with regard to conformational epitope prediction that warrants further laboratory experimental investigations in in vivo animal models.

  5. The LDBC Social Network Benchmark: Interactive Workload

    NARCIS (Netherlands)

    Erling, O.; Averbuch, A.; Larriba-Pey, J.; Chafi, H.; Gubichev, A.; Prat, A.; Pham, M.D.; Boncz, P.A.

    2015-01-01

    The Linked Data Benchmark Council (LDBC) is now two years underway and has gathered strong industrial participation for its mission to establish benchmarks, and benchmarking practices for evaluating graph data management systems. The LDBC introduced a new choke-point driven methodology for developin

  6. CD21(-/low) B cells in human blood are memory cells.

    Science.gov (United States)

    Thorarinsdottir, K; Camponeschi, A; Cavallini, N; Grimsholm, O; Jacobsson, L; Gjertsson, I; Mårtensson, I-L

    2016-08-01

    The complement receptor 2 (CR2, CD21) is part of a complex (CD21/CD19/CD81) acting as a co-receptor to the B cell receptor (BCR). Simultaneous triggering of the BCR and CD21 lowers the threshold for B cell activation. Although CD21 is important, B cells that express low amounts or lack surface CD21 (CD21(-/low) ) are increased in conditions with chronic inflammation, e.g. autoimmune diseases. However, little is known about the CD21(-/low) B cell subset in peripheral blood from healthy donors. Here, we show that CD21(-/low) cells represent approximately 5% of B cells in peripheral blood from adults but are barely detectable in cord blood, after excluding transitional B cells. The CD21(-/low) subset can be divided into CD38(-) 24(+) and CD38(-) 24(low) cells, where most of the CD38(-) 24(+) are CD27(+) immunoglobulin (Ig)M(+) IgD(+) and the CD38(-) 24(low) are switched CD27(-) . Expression levels of additional markers, e.g. CD95 and CD62L, are similar to those on classical memory B cells. In contrast to naive cells, the majority of CD21(-/low) cells lack expression of the ABCB1 transporter. Stimulation with a combination of BCR, Toll-like receptor (TLR)-7/8 and interleukin (IL)-2 induces proliferation and differentiation of the CD21(-/low) B cells comparable to CD21(+) CD27(+) memory B cells. The response excluding BCR agonist is not on par with that of classical memory B cells, although clearly above that of naive B cells. This is ascribed to a weaker response by the CD38(-) 24(low) subset, implying that some memory B cells require not only TLR but also BCR triggering. We conclude that the CD21(-/low) cells in healthy donors are memory B cells. PMID:27010233

  7. B-cell subsets, signaling and their roles in secretion of autoantibodies.

    Science.gov (United States)

    Iwata, S; Tanaka, Y

    2016-07-01

    B cells play a pivotal role in the pathogenesis of autoimmune diseases. In patients with systemic lupus erythematosus (SLE), the percentages of plasmablasts and IgD(-)CD27(-) double-negative memory B cells in peripheral blood are significantly increased, while IgD(+)CD27(+) IgM memory B cells are significantly decreased compared to healthy donors. The phenotypic change is significantly associated with disease activity and concentration of autoantibodies. Treatment of B-cell depletion using rituximab results in the reconstitution of peripheral B cells in SLE patients with subsequent improvement in disease activity. Numerous studies have described abnormalities in B-cell receptor (BCR)-mediated signaling in B cells of SLE patients. Since differences in BCR signaling are considered to dictate the survival or death of naïve and memory B cells, aberrant BCR signal can lead to abnormality of B-cell subsets in SLE patients. Although Syk and Btk function as key molecules in BCR signaling, their pathological role in SLE remains unclear. We found that Syk and Btk do not only transduce activation signal through BCR, but also mediate crosstalk between BCR and Toll-like receptor (TLR) as well as BCR and JAK-STAT pathways in human B cells in vitro. In addition, pronounced Syk and Btk phosphorylation was observed in B cells of patients with active SLE compared to those of healthy individuals. The results suggest the involvement of Syk and Btk activation in abnormalities of BCR-mediated signaling and B-cell phenotypes during the pathological process of SLE and that Syk, Btk and JAK are potential therapeutic targets in SLE. PMID:27252261

  8. Whole-genome fingerprint of the DNA methylome during human B cell differentiation

    OpenAIRE

    Kulis, Marta; Merkel, Angelika; Heath, Simon; Queirós, Ana C; Schuyler, Ronald P.; Castellano, Giancarlo; Beekman, Renée; Raineri, Emanuele; Esteve, Anna; Clot, Guillem; Verdaguer-Dot, Néria; Duran-Ferrer, Martí; Russiñol, Nuria; Vilarrasa-Blasi, Roser; Ecker, Simone

    2015-01-01

    International audience We analyzed the DNA methylome of ten subpopulations spanning the entire B cell differentiation program by whole-genome bisulfite sequencing and high-density microarrays. We observed that non-CpG methylation disappeared upon B cell commitment, whereas CpG methylation changed extensively during B cell maturation, showing an accumulative pattern and affecting around 30% of all measured CpG sites. Early differentiation stages mainly displayed enhancer demethylation, whic...

  9. Systemic Sclerosis Patients Present Alterations in the Expression of Molecules Involved in B-Cell Regulation

    Science.gov (United States)

    Soto, Lilian; Ferrier, Ashley; Aravena, Octavio; Fonseca, Elianet; Berendsen, Jorge; Biere, Andrea; Bueno, Daniel; Ramos, Verónica; Aguillón, Juan Carlos; Catalán, Diego

    2015-01-01

    The activation threshold of B cells is tightly regulated by an array of inhibitory and activator receptors in such a way that disturbances in their expression can lead to the appearance of autoimmunity. The aim of this study was to evaluate the expression of activating and inhibitory molecules involved in the modulation of B cell functions in transitional, naive, and memory B-cell subpopulations from systemic sclerosis patients. To achieve this, blood samples were drawn from 31 systemic sclerosis patients and 53 healthy individuals. Surface expression of CD86, MHC II, CD19, CD21, CD40, CD22, Siglec 10, CD35, and FcγRIIB was determined by flow cytometry. IL-10 production was evaluated by intracellular flow cytometry from isolated B cells. Soluble IL-6 and IL-10 levels were measured by ELISA from supernatants of stimulated B cells. Systemic sclerosis patients exhibit an increased frequency of transitional and naive B cells related to memory B cells compared with healthy controls. Transitional and naive B cells from patients express higher levels of CD86 and FcγRIIB than healthy donors. Also, B cells from patients show high expression of CD19 and CD40, whereas memory cells from systemic sclerosis patients show reduced expression of CD35. CD19 and CD35 expression levels associate with different autoantibody profiles. IL-10+ B cells and secreted levels of IL-10 were markedly reduced in patients. In conclusion, systemic sclerosis patients show alterations in the expression of molecules involved in B-cell regulation. These abnormalities may be determinant in the B-cell hyperactivation observed in systemic sclerosis. PMID:26483788

  10. T Cells That Promote B-Cell Maturation in Systemic Autoimmunity

    OpenAIRE

    Weinstein, Jason S.; Hernandez, Sairy G.; Craft, Joe

    2012-01-01

    Follicular helper T (Tfh) cells play an essential role in helping B cells generate antibodies upon pathogen encounters. Such T-cell help classically occurs in germinal centers (GCs) located in B-cell follicles of secondary lymphoid organs, a site of immunoglobulin affinity maturation and isotype switching. B-cell maturation also occurs extrafollicularly, in the red pulp of the spleen and medullary cords in lymph nodes, with plasma cell formation and antibody production. Development of extrafo...

  11. Bruton tyrosine kinase inhibitors: a promising novel targeted treatment for B cell lymphomas

    OpenAIRE

    Aalipour, Amin; Advani, Ranjana H.

    2013-01-01

    Constitutive or aberrant signalling of the B cell receptor signalling cascade has been implicated in the propagation and maintenance of a variety of B cell malignancies. Small molecule inhibitors of Bruton tyrosine kinase (BTK), a protein early in this cascade and specifically expressed in B cells, have emerged as a new class of targeted agents. There are several BTK inhibitors, including ONO-WG-307, LFM-A13, dasatinib, CC-292, and PCI-32765 (ibrutinib), in preclinical and/or clinical develop...

  12. Uptake and presentation of myelin basic protein by normal human B cells.

    Directory of Open Access Journals (Sweden)

    Marie Klinge Brimnes

    Full Text Available B cells may play both pathogenic and protective roles in T-cell mediated autoimmune diseases such as multiple sclerosis (MS. These functions relate to the ability of B cells to bind and present antigens. Under serum-free conditions we observed that 3-4% of circulating B cells from healthy donors were capable of binding the MS-associated self-antigen myelin basic protein (MBP and of presenting the immunodominant peptide MBP85-99, as determined by staining with the mAb MK16 recognising the peptide presented by HLA-DR15-positive cells. In the presence of serum, however, the majority of B cells bound MBP in a complement-dependent manner, and almost half of the B cells became engaged in presentation of MBP85-99. Even though complement receptor 1 (CR1, CD35 and CR2 (CD21 both contributed to binding of MBP to B cells, only CR2 was important for the subsequent presentation of MBP85-99. A high proportion of MBP85-99 presenting B cells expressed CD27, and showed increased expression of CD86 compared to non-presenting B cells. MBP-pulsed B cells induced a low frequency of IL-10-producing CD4+ T cells in 3 out of 6 donors, indicating an immunoregulatory role of B cells presenting MBP-derived peptides. The mechanisms described here refute the general assumption that B-cell presentation of self-antigens requires uptake via specific B-cell receptors, and may be important for maintenance of tolerance as well as for driving T-cell responses in autoimmune diseases.

  13. Diffuse large B-cell lymphoma with combined TP53 mutation and MIR34A> methylation

    DEFF Research Database (Denmark)

    Asmar, Fazila; Hother, Christoffer; Kulosman, Gorjan;

    2014-01-01

    MiR34A, B and C have been implicated in lymphomagenesis, but information on their role in normal CD19+ B-cells (PBL-B) and de novo diffuse large B-cell lymphoma (DLBCL) is limited. We show that in normal and activated B-cells miR34A-5p plays a dominant role compared to other miR34 family members....

  14. Recombinant human interleukin 2 acts as a B cell growth and differentiation promoting factor

    OpenAIRE

    Emmrich, F.; Moll, Heidrun; Markus M Simon

    2009-01-01

    Human B cells appropriately activated by a B cell mitogen are rendered susceptible to human Interleukin 2 (IL-2) as demonstrated with recombinant human IL-2 (rec. h IL-2). They show increased proliferation and drastically enhanced immunoglobulin secretion. Susceptibility to IL-2 is accompanied with the expression of the IL-2 receptor (Tac antigen) on B cells. The data suggest that IL-2 is one of the lymphokines directly involved in the activation of B lymphocytes.

  15. Identification of Autoantigen Epitopes in Alopecia Areata.

    Science.gov (United States)

    Wang, Eddy H C; Yu, Mei; Breitkopf, Trisia; Akhoundsadegh, Noushin; Wang, Xiaojie; Shi, Feng-Tao; Leung, Gigi; Dutz, Jan P; Shapiro, Jerry; McElwee, Kevin J

    2016-08-01

    Alopecia areata (AA) is believed to be a cell-mediated autoimmune hair loss disease. Both CD4 and cytotoxic CD8 T cells (CTLs) are important for the onset and progression of AA. Hair follicle (HF) keratinocyte and/or melanocyte antigen epitopes are suspected potential targets of autoreactive CTLs, but the specific epitopes have not yet been identified. We investigated the potential for a panel of known epitopes, expressed by HF keratinocytes and melanocytes, to induce activation of CTL populations in peripheral blood mononuclear cells. Specific synthetic epitopes derived from HF antigens trichohyalin and tyrosinase-related protein-2 induced significantly higher frequencies of response in AA CTLs compared with healthy controls (IFN-gamma secretion). Apoptosis assays revealed conditioned media from AA peripheral blood mononuclear cells stimulated with trichohyalin peptides elevated the expression of apoptosis markers in primary HF keratinocytes. A cytokine array revealed higher expression of IL-13 and chemokine ligand 5 (CCL5, RANTES) from AA peripheral blood mononuclear cells stimulated with trichohyalin peptides compared with controls. The data indicate that AA affected subjects present with an increased frequency of CTLs responsive to epitopes originating from keratinocytes and melanocytes; the activated CTLs secreted soluble factors that induced apoptosis in HF keratinocytes. Potentially, CTL response to self-antigen epitopes, particularly trichohyalin epitopes, could be a prognostic marker for human AA. PMID:27094591

  16. Chimeric Epitope Vaccine from Multistage Antigens for Lymphatic Filariasis.

    Science.gov (United States)

    Anugraha, G; Madhumathi, J; Prince, P R; Prita, P J Jeya; Khatri, V K; Amdare, N P; Reddy, M V R; Kaliraj, P

    2015-10-01

    Lymphatic filariasis, a mosquito-borne parasitic disease, affects more than 120 million people worldwide. Vaccination for filariasis by targeting different stages of the parasite will be a boon to the existing MDA efforts of WHO which required repeated administration of the drug to reduce the infection level and sustained transmission. Onset of a filaria-specific immune response achieved through antigen vaccines can act synergistically with these drugs to enhance the parasite killing. Multi-epitope vaccine approach has been proved to be successful against several parasitic diseases as it overcomes the limitations associated with the whole antigen vaccines. Earlier results from our group suggested the protective efficacy of multi-epitope vaccine comprising two immunodominant epitopes from Brugia malayi antioxidant thioredoxin (TRX), several epitopes from transglutaminase (TGA) and abundant larval transcript-2 (ALT-2). In this study, the prophylactic efficacy of the filarial epitope protein (FEP), a chimera of selective epitopes identified from our earlier study, was tested in a murine model (jird) of filariasis with L3 larvae. FEP conferred a significantly (P < 0.0001) high protection (69.5%) over the control in jirds. We also observed that the multi-epitope recombinant construct (FEP) induces multiple types of protective immune responses, thus ensuring the successful elimination of the parasite; this poses FEP as a potential vaccine candidate.

  17. Chimeric Epitope Vaccine from Multistage Antigens for Lymphatic Filariasis.

    Science.gov (United States)

    Anugraha, G; Madhumathi, J; Prince, P R; Prita, P J Jeya; Khatri, V K; Amdare, N P; Reddy, M V R; Kaliraj, P

    2015-10-01

    Lymphatic filariasis, a mosquito-borne parasitic disease, affects more than 120 million people worldwide. Vaccination for filariasis by targeting different stages of the parasite will be a boon to the existing MDA efforts of WHO which required repeated administration of the drug to reduce the infection level and sustained transmission. Onset of a filaria-specific immune response achieved through antigen vaccines can act synergistically with these drugs to enhance the parasite killing. Multi-epitope vaccine approach has been proved to be successful against several parasitic diseases as it overcomes the limitations associated with the whole antigen vaccines. Earlier results from our group suggested the protective efficacy of multi-epitope vaccine comprising two immunodominant epitopes from Brugia malayi antioxidant thioredoxin (TRX), several epitopes from transglutaminase (TGA) and abundant larval transcript-2 (ALT-2). In this study, the prophylactic efficacy of the filarial epitope protein (FEP), a chimera of selective epitopes identified from our earlier study, was tested in a murine model (jird) of filariasis with L3 larvae. FEP conferred a significantly (P < 0.0001) high protection (69.5%) over the control in jirds. We also observed that the multi-epitope recombinant construct (FEP) induces multiple types of protective immune responses, thus ensuring the successful elimination of the parasite; this poses FEP as a potential vaccine candidate. PMID:26179420

  18. Dissecting antibodies with regards to linear and conformational epitopes.

    Science.gov (United States)

    Forsström, Björn; Axnäs, Barbara Bisławska; Rockberg, Johan; Danielsson, Hanna; Bohlin, Anna; Uhlen, Mathias

    2015-01-01

    An important issue for the performance and specificity of an antibody is the nature of the binding to its protein target, including if the recognition involves linear or conformational epitopes. Here, we dissect polyclonal sera by creating epitope-specific antibody fractions using a combination of epitope mapping and an affinity capture approach involving both synthesized peptides and recombinant protein fragments. This allowed us to study the relative amounts of antibodies to linear and conformational epitopes in the polyclonal sera as well as the ability of each antibody-fraction to detect its target protein in Western blot assays. The majority of the analyzed polyclonal sera were found to have most of the target-specific antibodies directed towards linear epitopes and these were in many cases giving Western blot bands of correct molecular weight. In contrast, many of the antibodies towards conformational epitopes did not bind their target proteins in the Western blot assays. The results from this work have given us insights regarding the nature of the antibody response generated by immunization with recombinant protein fragments and has demonstrated the advantage of using antibodies recognizing linear epitopes for immunoassay involving wholly or partially denatured protein targets. PMID:25816293

  19. Dissecting antibodies with regards to linear and conformational epitopes.

    Directory of Open Access Journals (Sweden)

    Björn Forsström

    Full Text Available An important issue for the performance and specificity of an antibody is the nature of the binding to its protein target, including if the recognition involves linear or conformational epitopes. Here, we dissect polyclonal sera by creating epitope-specific antibody fractions using a combination of epitope mapping and an affinity capture approach involving both synthesized peptides and recombinant protein fragments. This allowed us to study the relative amounts of antibodies to linear and conformational epitopes in the polyclonal sera as well as the ability of each antibody-fraction to detect its target protein in Western blot assays. The majority of the analyzed polyclonal sera were found to have most of the target-specific antibodies directed towards linear epitopes and these were in many cases giving Western blot bands of correct molecular weight. In contrast, many of the antibodies towards conformational epitopes did not bind their target proteins in the Western blot assays. The results from this work have given us insights regarding the nature of the antibody response generated by immunization with recombinant protein fragments and has demonstrated the advantage of using antibodies recognizing linear epitopes for immunoassay involving wholly or partially denatured protein targets.

  20. Chemotherapy alone for localized diffuse large B-cell lymphoma.

    Science.gov (United States)

    Sehn, Laurie H

    2012-01-01

    Approximately 25% to 30% of patients with diffuse large B-cell lymphoma (DLBCL) present with limited-stage disease, typically defined as those with nonbulky (approaches have been used, which have largely relied on the administration of systemic therapy followed by involved-field radiation therapy (IFRT) to all sites of disease. The use of IFRT has been associated with improved local control, but a significant impact on long-term outcome has not been demonstrated. Although the inclusion of IFRT may allow for an abbreviated course of chemotherapy to be administered, this benefit must be weighed against the potential for radiation-induced acute and delayed toxicity. With the advent of improved systemic therapy, the routine use of IFRT in all patients with limited-stage DLBCL seems no longer justifiable. A tailored-therapy approach, with choice of treatment guided by patient performance status and chemotherapy tolerance, sites of disease involvement, clinical risk factors, and early treatment response would seem rational. Ultimately, greater biologic insight into the heterogeneity of DLBCL will likely result in a personalized treatment approach that relies more on biologic characteristics than stage of disease. PMID:23006946

  1. Cerebral infratentorial large B-cell lymphoma presenting as Parkinsonism.

    Science.gov (United States)

    Lin, Chih-Ming; Hong, Kelvin

    2010-03-01

    Though rare, primary intracranial tumors can present with Parkinsonian symptoms, and diagnosis can be delayed unless there is a high index of suspicion. We herein present an 81-year-old man who was seen in our neurology clinic due to acute onset of unsteady gait and altered consciousness. Parkinsonism was initially diagnosed because of the typical manifestations. Levodopa was prescribed; however, there was a limited effect on his symptoms. Upon detail history and neurological examination, left sided hemiparesis was disclosed. Cerebral imaging studies revealed a solid mass over the right infratentorial para-midbrain area leading to reactive obstructive hydrocephalus. Work-up including chest and abdominal CT scanning, upper and lower GI endoscopy, and tumor marker studies failed to uncover any abnormalities. A neurosurgeon was consulted and a shunt procedure and biopsy of the infratentorial mass were performed. Histopathological examination of the biopsy tissue revealed tumor diffusely intermixed with large cells consistent with large B-cell lymphoma. The patient and his family declined further treatment. Though rare, cerebral tumors can present with Parkinsonian features and represent a diagnostic challenge. Clinicians should be aware of the possibility of cerebral neoplasms causing Parkinsonism, and include them in the differential diagnosis, especially for patients presenting with atypical Parkinsonian features, or those not responsive to initial therapy.

  2. Prognostic Assessment in Patients with Indolent B-Cell Lymphomas

    Directory of Open Access Journals (Sweden)

    Luca Arcaini

    2012-01-01

    Full Text Available Follicular lymphoma (FL is an indolent lymphoma with long median survival. Many studies have been performed to build up prognostic scores potentially useful to identify patients with poorer outcome. In 2004, an international consortium coordinated by the International Follicular Lymphoma Prognostic Factor project was established and a new prognostic study was launched (FLIPI2 using progression-free survival (PFS as main endpoint and integrating all the modern parameters prospectively collected. Low-grade non-Hodgkin lymphomas were once considered as a heterogenous group of lymphomas characterized by an indolent clinical course. Each entity is characterized by unique clinicobiologic features. Some studies have been focused on prognostic factors in single lymphoma subtypes, with the development of specific-entity scores based on retrospective series, for instance splenic marginal zone lymphoma (SMZL. A widely accepted prognostic tool for clinical usage for indolent non-follicular B-cell lymphomas is largely awaited. In this paper we summarized the current evidence regarding prognostic assessment of indolent follicular and non-follicular lymphomas.

  3. Antibody and B cell responses to Plasmodium sporozoites

    Directory of Open Access Journals (Sweden)

    Johanna N Dups

    2014-11-01

    Full Text Available Antibodies are capable of blocking infection of the liver by Plasmodium sporozoites. Accordingly the induction of anti-sporozoite antibodies is a major aim of various vaccine approaches to malaria. In recent years our knowledge of the specificity and quantities of antibodies required for protection has been greatly expanded by clinical trials of various whole sporozoite and subunit vaccines. Moreover, the development of humanized mouse models and transgenic parasites have also aided our ability to assess the specificity of antibodies and their ability to block infection. Nonetheless, considerable gaps remain in our knowledge - in particular in understanding what antigens are recognized by infection blocking antibodies and in knowing how we can induce robust, long-lived antibody responses. Maintaining high levels of circulating antibodies is likely to be of primary importance, as antibodies must block infection in the short time it takes for sporozoites to reach the liver from the skin. It is clear that a better understanding of the development of protective B cell-mediated immunity will aid the development and refinement of malaria vaccines.

  4. Multifocal Extranodal Involvement of Diffuse Large B-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Devrim Cabuk

    2013-01-01

    Full Text Available Endobronchial involvement of extrapulmonary malignant tumors is uncommon and mostly associated with breast, kidney, colon, and rectum carcinomas. A 68-year-old male with a prior diagnosis of colon non-Hodgkin lymphoma (NHL was admitted to the hospital with a complaint of cough, sputum, and dyspnea. The chest radiograph showed right hilar enlargement and opacity at the right middle zone suggestive of a mass lesion. Computed tomography of thorax revealed a right-sided mass lesion extending to thoracic wall with the destruction of the third and the fourth ribs and a right hilar mass lesion. Fiberoptic bronchoscopy was performed in order to evaluate endobronchial involvement and showed stenosis with mucosal tumor infiltration in right upper lobe bronchus. The pathological examination of bronchoscopic biopsy specimen reported diffuse large B-cell lymphoma and the patient was accepted as the endobronchial recurrence of sigmoid colon NHL. The patient is still under treatment of R-ICE (rituximab-ifosfamide-carboplatin-etoposide chemotherapy and partial regression of pulmonary lesions was noted after 3 courses of treatment.

  5. Primary Mediastinal Large B-Cell Lymphoma during Pregnancy

    Directory of Open Access Journals (Sweden)

    Cesar A. Perez

    2012-01-01

    Full Text Available Non-Hodgkin’s Lymphoma (NHL rarely presents during pregnancy and primary mediastinal large B-cell lymphoma (PMLBCL accounts for approximately 2.5% of patients with NHL. The case of a 22-year-old woman who was diagnosed with Stage IIA PMLBCL during week 13 of her intrauterine pregnancy is described. The staging consisted in computed tomography (CT of the chest and magnetic resonance imaging (MRI of the abdomen and pelvis. She was managed with R-CHOP regimen (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone for a total of six cycles and, because of the early presentation during the second trimester, she received the entire chemotherapy course during the pregnancy. She delivered a healthy baby at 34 weeks of pregnancy and a 18FDG-PET/CT scan demonstrated complete remission after delivery. After 20 months of follow up she remains with no evidence of disease and her 1-year-old son has shown no developmental delays or physical abnormalities. PMLBCL, although an uncommon subgroup of DLBCL, may present during pregnancy and R-CHOP should be considered as one suitable option in this complex scenario.

  6. EVALUATION OF CYTOKINE GENE POLYMORPHISM IN B CELL LYMPHOID MALIGNANCIES

    Directory of Open Access Journals (Sweden)

    E. L. Nazarova

    2014-01-01

    Full Text Available Previous studies with some solid tumors has shown that polymorphisms of certain cytokine genes may be used as predictors of clinical outcome in the patients. It seemed important to evaluate potential correlations between production of certain pro- and anti-inflammatory cytokines and co-receptor molecules, and promoter polymorphism of the cytokine genes involved into regulation of cell proliferation, differentiation, apoptosis, lipid metabolism and blood clotting in the patients with hematological malignancies. The article contains our results concerning associations between of IL-1β, -2, -4, -10, -17, TNFα, and allelic polymorphisms of their genes in 62 patients with B cell lymphoid malignancies in an ethnically homogenous group (self-identified as Russians. We have shown that the GА and AA genotypes of the G-308A polymorphism in TNFα gene are significantly associated with increased production of this cytokine, being more common in aggressive non-Hodgkin lymphomas, more rare in multiple myeloma and in indolent non-Hodgkin lymphomas.

  7. Gastric Marginal Zone B Cell Lymphoma of the Duodenum

    Directory of Open Access Journals (Sweden)

    A. Ndzengue

    2011-10-01

    Full Text Available Small bowel lymphomas of the extranodal type occur in the young and are characteristically associated with malabsorption syndrome. We present the case of an elderly in whom there was no malabsorption and the duodenal tumor was a gastric type marginal zone B cell lymphoma also known as gastric mucosa-associated lymphoid tissue (MALT lymphoma. A 73-year-old woman presented to the emergency room with 2 weeks of general weakness, recurrent vomiting containing food particles and abdominal distension. She had been diagnosed with diabetic gastroparesis 4 years prior. CT of the abdomen and pelvis was suggestive of gastric outlet obstruction but no evidence of pancreatic or duodenal mass. Endoscopy and biopsy of the tumor obstructing the distal first part of the duodenum confirmed a gastric marginal MALT lymphoma. The patient’s symptoms improved with radiotherapy. Gastric MALT lymphoma, an extranodal lymphoma primarily described in the stomach, can also present in the small bowel and is not associated with malabsorption.

  8. B Cells Promote Th1- Skewed NKT Cell Response by CD1d-TCR Interaction

    OpenAIRE

    Shin, Jung Hoon; Park, Se-Ho

    2013-01-01

    CD1d expressing dendritic cells (DCs) are good glyco-lipid antigen presenting cells for NKT cells. However, resting B cells are very weak stimulators for NKT cells. Although α-galactosylceramide (α-GalCer) loaded B cells can activate NKT cells, it is not well defined whether B cells interfere NKT cell stimulating activity of DCs. Unexpectedly, we found in this study that B cells can promote Th1-skewed NKT cell response, which means a increased level of IFN-γ by NKT cells, concomitant with a d...

  9. B cells help alloreactive T cells differentiate into memory T cells1

    OpenAIRE

    Ng, Yue-Harn; Oberbarnscheidt, Martin H.; Chandramoorthy, Harish Chinna Konda; Hoffman, Rosemary; Chalasani, Geetha

    2010-01-01

    B cells are recognized as effector cells in allograft rejection that are dependent upon T cell help to produce alloantibodies causing graft injury. It is not known if B cells can also help T cells differentiate into memory cells in the alloimmune response. We found that in B cell-deficient hosts, differentiation of alloreactive T cells into effectors was intact whereas their development into memory T cells was impaired. To test if B cell help for T cells was required for their continued diffe...

  10. Affinity-purified interleukin 2 induces proliferation of large but not small B cells.

    OpenAIRE

    Mond, J J; C. Thompson; Finkelman, F.D.; Farrar, J.; Schaefer, M.; Robb, R J

    1985-01-01

    Immunoaffinity-purified interleukin 2 (IL2) stimulated proliferation of large but not small B cells. Stimulation was observed even when B cells were cultured at very low cell densities (3 X 10(4) per microwell containing 0.2 ml of medium). Addition of small numbers of purified splenic T cells did not enhance the IL2-induced B-cell proliferative response. These results suggest that IL2 was not operating through contaminating T cells. B cells cultured with anti-Ig antibody in vitro showed enhan...

  11. Clonal expansion of immunoglobulin M+CD27+ B cells in HCV-associated mixed cryoglobulinemia

    OpenAIRE

    Charles, Edgar D.; Green, Rashidah M.; Marukian, Svetlana; Talal, Andrew H.; Lake-Bakaar, Gerond V.; Jacobson, Ira M.; Rice, Charles M.; Dustin, Lynn B.

    2008-01-01

    Hepatitis C virus (HCV) is associated with B-cell lymphoproliferative disorders such as mixed cryoglobulinemia (MC) and B-cell non-Hodgkin lymphoma (B-NHL). The pathogenesis of these disorders remains unclear, and it has been proposed that HCV drives the pro-liferation of B cells. Here we demonstrate that certain HCV+MC+ subjects have clonal expansions of immunoglobulin M (IgM)+κ+IgDlow/−CD21lowCD27+ B cells. Using RT-PCR to amplify Ig from these singly sorted cells, we show that these predom...

  12. Pathogenic functions of B cells in autoimmune diseases: IFN-γ production joins the criminal gang.

    Science.gov (United States)

    Fillatreau, Simon

    2015-04-01

    B-cell depletion therapy has emerged as a powerful strategy to intercept the progression of T-cell-mediated autoimmune diseases such as rheumatoid arthritis, type 1 diabetes, or relapsing remitting multiple sclerosis. However, its mode of action remains incompletely defined, reflecting our incomplete understanding of the pathogenic functions of B cells in such pathologies. B cells can contribute to immune responses through the production of antibodies, presentation of antigen to T cells, and production of cytokines. In this issue of the European Journal of Immunology [Eur. J. Immunol. 2015. 45: 988-998], Olalekan et al. demonstrate that IFN-γ production by B cells is essential for the development of arthritis in mice. Lack of IFN-γ expression in B cells results in reduced autoimmune T-cell responses and autoantibody levels, impacting the arthritogenic reaction akin to that in B-cell depletion therapy. Together with other reports, the article by Olalekan et al. emphasizes the importance of cytokine-producing B cells in the pathogenesis of autoimmune diseases. In this commentary, I discuss how these findings shed new light on the roles of B cells as drivers of autoimmune pathogenesis, and how they more generally contribute to our understanding of the role of B cells in immunity.

  13. CEACAM1 induces B-cell survival and is essential for protective antiviral antibody production

    OpenAIRE

    Khairnar, Vishal; Duhan, Vikas; Maney, Sathish Kumar; Honke, Nadine; Shaabani, Namir; Pandyra, Aleksandra A; Seifert, Marc; Pozdeev, Vitaly; Xu, Haifeng C.; Sharma, Piyush; Baldin, Fabian; Marquardsen, Florian; Merches, Katja; Lang, Elisabeth; Kirschning, Carsten

    2015-01-01

    B cells are essential for antiviral immune defence because they produce neutralizing antibodies, present antigen and maintain the lymphoid architecture. Here we show that intrinsic signalling of CEACAM1 is essential for generating efficient B-cell responses. Although CEACAM1 exerts limited influence on the proliferation of B cells, expression of CEACAM1 induces survival of proliferating B cells via the BTK/Syk/NF-κB-axis. The absence of this signalling cascade in naive Ceacam1 −/− mice limits...

  14. Signaling and Dynamic Actin Responses of B Cells on Topographical Substrates

    Science.gov (United States)

    Ketchum, Christina; Sun, Xiaoyu; Fourkas, John; Song, Wenxia; Upadhyaya, Arpita

    B cells become activated upon physical contact with antigen on the surface of antigen presenting cells, such as dendritic cells. Binding of the B cell receptor with antigen initiates actin-mediated spreading of B cells, signaling cascades and eventually infection fighting antibodies. Lymphocytes, including B cells and T cells, have been shown to be responsive to the physical parameters of the contact surface, such as antigen mobility and substrate stiffness. However the roll of surface topography on lymphocyte function is unknown. Here we investigate the degree to which substrate topography controls actin-mediated spreading and B cell activation using nano-fabricated surfaces and live cell imaging. The model topographical system consists of 600 nanometer tall ridges with spacing varying between 800 nanometers and 5 micrometers. Using TIRF imaging we observe actin dynamics, B cell receptor motion and calcium signaling of B cells as they spread on the ridged substrates. We show that the spacing between ridges had a strong effect on the dynamics of actin and calcium influx on B cells. Our results indicate that B cells are highly sensitive to surface topography during cell spreading and signaling activation.

  15. High levels of SOX5 decrease proliferative capacity of human B cells, but permit plasmablast differentiation.

    Science.gov (United States)

    Rakhmanov, Mirzokhid; Sic, Heiko; Kienzler, Anne-Kathrin; Fischer, Beate; Rizzi, Marta; Seidl, Maximilian; Melkaoui, Kerstina; Unger, Susanne; Moehle, Luisa; Schmit, Nadine E; Deshmukh, Sachin D; Ayata, Cemil Korcan; Schuh, Wolfgang; Zhang, Zhibing; Cosset, François-Loic; Verhoeyen, Els; Peter, Hans-Hartmut; Voll, Reinhard E; Salzer, Ulrich; Eibel, Hermann; Warnatz, Klaus

    2014-01-01

    Currently very little is known about the differential expression and function of the transcription factor SOX5 during B cell maturation. We identified two new splice variants of SOX5 in human B cells, encoding the known L-SOX5B isoform and a new shorter isoform L-SOX5F. The SOX5 transcripts are highly expressed during late stages of B-cell differentiation, including atypical memory B cells, activated CD21low B cells and germinal center B cells of tonsils. In tonsillar sections SOX5 expression was predominantly polarized to centrocytes within the light zone. After in vitro stimulation, SOX5 expression was down-regulated during proliferation while high expression levels were permissible for plasmablast differentiation. Overexpression of L-SOX5F in human primary B lymphocytes resulted in reduced proliferation, less survival of CD138neg B cells, but comparable numbers of CD138+CD38hi plasmablasts compared to control cells. Thus, our findings describe for the first time a functional role of SOX5 during late B cell development reducing the proliferative capacity and thus potentially affecting the differentiation of B cells during the germinal center response. PMID:24945754

  16. High levels of SOX5 decrease proliferative capacity of human B cells, but permit plasmablast differentiation.

    Directory of Open Access Journals (Sweden)

    Mirzokhid Rakhmanov

    Full Text Available Currently very little is known about the differential expression and function of the transcription factor SOX5 during B cell maturation. We identified two new splice variants of SOX5 in human B cells, encoding the known L-SOX5B isoform and a new shorter isoform L-SOX5F. The SOX5 transcripts are highly expressed during late stages of B-cell differentiation, including atypical memory B cells, activated CD21low B cells and germinal center B cells of tonsils. In tonsillar sections SOX5 expression was predominantly polarized to centrocytes within the light zone. After in vitro stimulation, SOX5 expression was down-regulated during proliferation while high expression levels were permissible for plasmablast differentiation. Overexpression of L-SOX5F in human primary B lymphocytes resulted in reduced proliferation, less survival of CD138neg B cells, but comparable numbers of CD138+CD38hi plasmablasts compared to control cells. Thus, our findings describe for the first time a functional role of SOX5 during late B cell development reducing the proliferative capacity and thus potentially affecting the differentiation of B cells during the germinal center response.

  17. CEACAM1 mediates B cell aggregation in central nervous system autoimmunity.

    Science.gov (United States)

    Rovituso, Damiano M; Scheffler, Laura; Wunsch, Marie; Kleinschnitz, Christoph; Dörck, Sebastian; Ulzheimer, Jochen; Bayas, Antonios; Steinman, Lawrence; Ergün, Süleyman; Kuerten, Stefanie

    2016-01-01

    B cell aggregates in the central nervous system (CNS) have been associated with rapid disease progression in patients with multiple sclerosis (MS). Here we demonstrate a key role of carcinoembryogenic antigen-related cell adhesion molecule1 (CEACAM1) in B cell aggregate formation in MS patients and a B cell-dependent mouse model of MS. CEACAM1 expression was increased on peripheral blood B cells and CEACAM1(+) B cells were present in brain infiltrates of MS patients. Administration of the anti-CEACAM1 antibody T84.1 was efficient in blocking aggregation of B cells derived from MS patients. Along these lines, application of the monoclonal anti-CEACAM1 antibody mCC1 was able to inhibit CNS B cell aggregate formation and significantly attenuated established MS-like disease in mice in the absence of any adverse effects. CEACAM1 was co-expressed with the regulator molecule T cell immunoglobulin and mucin domain -3 (TIM-3) on B cells, a novel molecule that has recently been described to induce anergy in T cells. Interestingly, elevated coexpression on B cells coincided with an autoreactive T helper cell phenotype in MS patients. Overall, these data identify CEACAM1 as a clinically highly interesting target in MS pathogenesis and open new therapeutic avenues for the treatment of the disease. PMID:27435215

  18. Variant B Cell Receptor Isotype Functions Differ in Hairy Cell Leukemia with Mutated BRAF and IGHV Genes

    NARCIS (Netherlands)

    Weston-Bell, Nicola J.; Forconi, Francesco; Kluin-Nelemans, Hanneke C.; Sahota, Surinder S.

    2014-01-01

    A functional B-cell receptor (BCR) is critical for survival of normal B-cells, but whether it plays a comparable role in B-cell malignancy is as yet not fully delineated. Typical Hairy Cell Leukemia (HCL) is a rare B-cell tumor, and unique in expressing multiple surface immunoglobulin (sIg) isotypes

  19. Geothermal Heat Pump Benchmarking Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1997-01-17

    A benchmarking study was conducted on behalf of the Department of Energy to determine the critical factors in successful utility geothermal heat pump programs. A Successful program is one that has achieved significant market penetration. Successfully marketing geothermal heat pumps has presented some major challenges to the utility industry. However, select utilities have developed programs that generate significant GHP sales. This benchmarking study concludes that there are three factors critical to the success of utility GHP marking programs: (1) Top management marketing commitment; (2) An understanding of the fundamentals of marketing and business development; and (3) An aggressive competitive posture. To generate significant GHP sales, competitive market forces must by used. However, because utilities have functioned only in a regulated arena, these companies and their leaders are unschooled in competitive business practices. Therefore, a lack of experience coupled with an intrinsically non-competitive culture yields an industry environment that impedes the generation of significant GHP sales in many, but not all, utilities.

  20. Methodology for Benchmarking IPsec Gateways

    Directory of Open Access Journals (Sweden)

    Adam Tisovský

    2012-08-01

    Full Text Available The paper analyses forwarding performance of IPsec gateway over the rage of offered loads. It focuses on the forwarding rate and packet loss particularly at the gateway’s performance peak and at the state of gateway’s overload. It explains possible performance degradation when the gateway is overloaded by excessive offered load. The paper further evaluates different approaches for obtaining forwarding performance parameters – a widely used throughput described in RFC 1242, maximum forwarding rate with zero packet loss and us proposed equilibrium throughput. According to our observations equilibrium throughput might be the most universal parameter for benchmarking security gateways as the others may be dependent on the duration of test trials. Employing equilibrium throughput would also greatly shorten the time required for benchmarking. Lastly, the paper presents methodology and a hybrid step/binary search algorithm for obtaining value of equilibrium throughput.

  1. Restaurant Energy Use Benchmarking Guideline

    Energy Technology Data Exchange (ETDEWEB)

    Hedrick, R.; Smith, V.; Field, K.

    2011-07-01

    A significant operational challenge for food service operators is defining energy use benchmark metrics to compare against the performance of individual stores. Without metrics, multiunit operators and managers have difficulty identifying which stores in their portfolios require extra attention to bring their energy performance in line with expectations. This report presents a method whereby multiunit operators may use their own utility data to create suitable metrics for evaluating their operations.

  2. TRIGA Mark II benchmark experiment

    International Nuclear Information System (INIS)

    Experimental results of pulse parameters and control rod worth measurements at TRIGA Mark 2 reactor in Ljubljana are presented. The measurements were performed with a completely fresh, uniform, and compact core. Only standard fuel elements with 12 wt% uranium were used. Special efforts were made to get reliable and accurate results at well-defined experimental conditions, and it is proposed to use the results as a benchmark test case for TRIGA reactors

  3. OCA-B integrates B cell antigen receptor-, CD40L- and IL 4-mediated signals for the germinal center pathway of B cell development.

    OpenAIRE

    Qin, X F; Reichlin, A; Luo, Y.; Roeder, R. G.; Nussenzweig, M.C.

    1998-01-01

    Many of the key decisions in lymphocyte differentiation and activation are dependent on integration of antigen receptor and co-receptor signals. Although there is significant understanding of these receptors and their signaling pathways, little is known about the molecular requirements for signal integration at the level of activation of gene expression. Here we show that in primary B cells, expression of the B-cell specific transcription coactivator OCA-B (also known as OBF-1 or Bob-1) is re...

  4. RISKIND verification and benchmark comparisons

    International Nuclear Information System (INIS)

    This report presents verification calculations and benchmark comparisons for RISKIND, a computer code designed to estimate potential radiological consequences and health risks to individuals and the population from exposures associated with the transportation of spent nuclear fuel and other radioactive materials. Spreadsheet calculations were performed to verify the proper operation of the major options and calculational steps in RISKIND. The program is unique in that it combines a variety of well-established models into a comprehensive treatment for assessing risks from the transportation of radioactive materials. Benchmark comparisons with other validated codes that incorporate similar models were also performed. For instance, the external gamma and neutron dose rate curves for a shipping package estimated by RISKIND were compared with those estimated by using the RADTRAN 4 code and NUREG-0170 methodology. Atmospheric dispersion of released material and dose estimates from the GENII and CAP88-PC codes. Verification results have shown the program to be performing its intended function correctly. The benchmark results indicate that the predictions made by RISKIND are within acceptable limits when compared with predictions from similar existing models

  5. Thermal Performance Benchmarking: Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, Gilbert

    2016-04-08

    The goal for this project is to thoroughly characterize the performance of state-of-the-art (SOA) automotive power electronics and electric motor thermal management systems. Information obtained from these studies will be used to: Evaluate advantages and disadvantages of different thermal management strategies; establish baseline metrics for the thermal management systems; identify methods of improvement to advance the SOA; increase the publicly available information related to automotive traction-drive thermal management systems; help guide future electric drive technologies (EDT) research and development (R&D) efforts. The performance results combined with component efficiency and heat generation information obtained by Oak Ridge National Laboratory (ORNL) may then be used to determine the operating temperatures for the EDT components under drive-cycle conditions. In FY15, the 2012 Nissan LEAF power electronics and electric motor thermal management systems were benchmarked. Testing of the 2014 Honda Accord Hybrid power electronics thermal management system started in FY15; however, due to time constraints it was not possible to include results for this system in this report. The focus of this project is to benchmark the thermal aspects of the systems. ORNL's benchmarking of electric and hybrid electric vehicle technology reports provide detailed descriptions of the electrical and packaging aspects of these automotive systems.

  6. Adapting benchmarking to project management : an analysis of project management processes, metrics, and benchmarking process models

    OpenAIRE

    Emhjellen, Kjetil

    1997-01-01

    Since the first publication on benchmarking in 1989 by Robert C. Camp of “Benchmarking: The search for Industry Best Practices that Lead to Superior Performance”, the improvement technique benchmarking has been established as an important tool in the process focused manufacturing or production environment. The use of benchmarking has expanded to other types of industry. Benchmarking has past the doorstep and is now in early trials in the project and construction environment....

  7. HS06 Benchmark for an ARM Server

    Science.gov (United States)

    Kluth, Stefan

    2014-06-01

    We benchmarked an ARM cortex-A9 based server system with a four-core CPU running at 1.1 GHz. The system used Ubuntu 12.04 as operating system and the HEPSPEC 2006 (HS06) benchmarking suite was compiled natively with gcc-4.4 on the system. The benchmark was run for various settings of the relevant gcc compiler options. We did not find significant influence from the compiler options on the benchmark result. The final HS06 benchmark result is 10.4.

  8. HS06 Benchmark for an ARM Server

    CERN Document Server

    Kluth, Stefan

    2013-01-01

    We benchmarked an ARM cortex-A9 based server system with a four-core CPU running at 1.1 GHz. The system used Ubuntu 12.04 as operating system and the HEPSPEC 2006 (HS06) benchmarking suite was compiled natively with gcc-4.4 on the system. The benchmark was run for various settings of the relevant gcc compiler options. We did not find significant influence from the compiler options on the benchmark result. The final HS06 benchmark result is 10.4.

  9. Identification of cytotoxic T lymphocyte epitopes on swine viruses: multi-epitope design for universal T cell vaccine.

    Directory of Open Access Journals (Sweden)

    Yu-Chieh Liao

    Full Text Available Classical swine fever (CSF, foot-and-mouth disease (FMD and porcine reproductive and respiratory syndrome (PRRS are the primary diseases affecting the pig industry globally. Vaccine induced CD8(+ T cell-mediated immune response might be long-lived and cross-serotype and thus deserve further attention. Although large panels of synthetic overlapping peptides spanning the entire length of the polyproteins of a virus facilitate the detection of cytotoxic T lymphocyte (CTL epitopes, it is an exceedingly costly and cumbersome approach. Alternatively, computational predictions have been proven to be of satisfactory accuracy and are easily performed. Such a method enables the systematic identification of genome-wide CTL epitopes by incorporating epitope prediction tools in analyzing large numbers of viral sequences. In this study, we have implemented an integrated bioinformatics pipeline for the identification of CTL epitopes of swine viruses including the CSF virus (CSFV, FMD virus (FMDV and PRRS virus (PRRSV and assembled these epitopes on a web resource to facilitate vaccine design. Identification of epitopes for cross protections to different subtypes of virus are also reported in this study and may be useful for the development of a universal vaccine against such viral infections among the swine population. The CTL epitopes identified in this study have been evaluated in silico and possibly provide more and wider protection in compared to traditional single-reference vaccine design. The web resource is free and open to all users through http://sb.nhri.org.tw/ICES.

  10. Early B-cell factor 1 (EBF1) is critical for transcriptional control of SLAMF1 gene in human B cells.

    Science.gov (United States)

    Schwartz, Anton M; Putlyaeva, Lidia V; Covich, Milica; Klepikova, Anna V; Akulich, Kseniya A; Vorontsov, Ilya E; Korneev, Kirill V; Dmitriev, Sergey E; Polanovsky, Oleg L; Sidorenko, Svetlana P; Kulakovskiy, Ivan V; Kuprash, Dmitry V

    2016-10-01

    Signaling lymphocytic activation molecule family member 1 (SLAMF1)/CD150 is a co-stimulatory receptor expressed on a variety of hematopoietic cells, in particular on mature lymphocytes activated by specific antigen, costimulation and cytokines. Changes in CD150 expression level have been reported in association with autoimmunity and with B-cell chronic lymphocytic leukemia. We characterized the core promoter for SLAMF1 gene in human B-cell lines and explored binding sites for a number of transcription factors involved in B cell differentiation and activation. Mutations of SP1, STAT6, IRF4, NF-kB, ELF1, TCF3, and SPI1/PU.1 sites resulted in significantly decreased promoter activity of varying magnitude, depending on the cell line tested. The most profound effect on the promoter strength was observed upon mutation of the binding site for Early B-cell factor 1 (EBF1). This mutation produced a 10-20 fold drop in promoter activity and pinpointed EBF1 as the master regulator of human SLAMF1 gene in B cells. We also identified three potent transcriptional enhancers in human SLAMF1 locus, each containing functional EBF1 binding sites. Thus, EBF1 interacts with specific binding sites located both in the promoter and in the enhancer regions of the SLAMF1 gene and is critical for its expression in human B cells. PMID:27424222

  11. The spectrum of B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma: a description of 10 cases.

    Science.gov (United States)

    Gualco, Gabriela; Natkunam, Yasodha; Bacchi, Carlos E

    2012-05-01

    B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma, is a diagnostic provisional category in the World Health Organization (WHO) 2008 classification of lymphomas. This category was designed as a measure to accommodate borderline cases that cannot be reliably classified into a single distinct disease entity after all available morphological, immunophenotypical and molecular studies have been performed. Typically, these cases share features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma, or include characteristics of both lymphomas. The rarity of such cases poses a tremendous challenge to both pathologists and oncologists because its differential diagnosis has direct implications for management strategies. In this study, we present 10 cases of B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma and have organized the criteria described by the WHO into four patterns along with detailed clinical, morphological and immunophenotypic characterization and outcome data. Our findings show a male preponderance, median age of 37 years and a mediastinal presentation in 80% of cases. All cases expressed at least two markers associated with B-cell lineage and good response to combination chemotherapy currently employed for non-Hodgkin lymphomas.

  12. Early B-cell factor 1 (EBF1) is critical for transcriptional control of SLAMF1 gene in human B cells.

    Science.gov (United States)

    Schwartz, Anton M; Putlyaeva, Lidia V; Covich, Milica; Klepikova, Anna V; Akulich, Kseniya A; Vorontsov, Ilya E; Korneev, Kirill V; Dmitriev, Sergey E; Polanovsky, Oleg L; Sidorenko, Svetlana P; Kulakovskiy, Ivan V; Kuprash, Dmitry V

    2016-10-01

    Signaling lymphocytic activation molecule family member 1 (SLAMF1)/CD150 is a co-stimulatory receptor expressed on a variety of hematopoietic cells, in particular on mature lymphocytes activated by specific antigen, costimulation and cytokines. Changes in CD150 expression level have been reported in association with autoimmunity and with B-cell chronic lymphocytic leukemia. We characterized the core promoter for SLAMF1 gene in human B-cell lines and explored binding sites for a number of transcription factors involved in B cell differentiation and activation. Mutations of SP1, STAT6, IRF4, NF-kB, ELF1, TCF3, and SPI1/PU.1 sites resulted in significantly decreased promoter activity of varying magnitude, depending on the cell line tested. The most profound effect on the promoter strength was observed upon mutation of the binding site for Early B-cell factor 1 (EBF1). This mutation produced a 10-20 fold drop in promoter activity and pinpointed EBF1 as the master regulator of human SLAMF1 gene in B cells. We also identified three potent transcriptional enhancers in human SLAMF1 locus, each containing functional EBF1 binding sites. Thus, EBF1 interacts with specific binding sites located both in the promoter and in the enhancer regions of the SLAMF1 gene and is critical for its expression in human B cells.

  13. Design and Characterization of Epitope-Scaffold Immunogens That Present the Motavizumab Epitope from Respiratory Syncytial Virus

    Energy Technology Data Exchange (ETDEWEB)

    McLellan, Jason S.; Correia, Bruno E.; Chen, Man; Yang, Yongping; Graham, Barney S.; Schief, William R.; Kwong, Peter D. (UWASH); (NIH)

    2012-06-28

    Respiratory syncytial virus (RSV) is a major cause of respiratory tract infections in infants, but an effective vaccine has not yet been developed. An ideal vaccine would elicit protective antibodies while avoiding virus-specific T-cell responses, which have been implicated in vaccine-enhanced disease with previous RSV vaccines. We propose that heterologous proteins designed to present RSV-neutralizing antibody epitopes and to elicit cognate antibodies have the potential to fulfill these vaccine requirements, as they can be fashioned to be free of viral T-cell epitopes. Here we present the design and characterization of three epitope-scaffolds that present the epitope of motavizumab, a potent neutralizing antibody that binds to a helix-loop-helix motif in the RSV fusion glycoprotein. Two of the epitope-scaffolds could be purified, and one epitope-scaffold based on a Staphylococcus aureus protein A domain bound motavizumab with kinetic and thermodynamic properties consistent with the free epitope-scaffold being stabilized in a conformation that closely resembled the motavizumab-bound state. This epitope-scaffold was well folded as assessed by circular dichroism and isothermal titration calorimetry, and its crystal structure (determined in complex with motavizumab to 1.9 {angstrom} resolution) was similar to the computationally designed model, with all hydrogen-bond interactions critical for binding to motavizumab preserved. Immunization of mice with this epitope-scaffold failed to elicit neutralizing antibodies but did elicit sera with F binding activity. The elicitation of F binding antibodies suggests that some of the design criteria for eliciting protective antibodies without virus-specific T-cell responses are being met, but additional optimization of these novel immunogens is required.

  14. Argonne Code Center: Benchmark problem book.

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1977-06-01

    This book is an outgrowth of activities of the Computational Benchmark Problems Committee of the Mathematics and Computation Division of the American Nuclear Society. This is the second supplement of the original benchmark book which was first published in February, 1968 and contained computational benchmark problems in four different areas. Supplement No. 1, which was published in December, 1972, contained corrections to the original benchmark book plus additional problems in three new areas. The current supplement. Supplement No. 2, contains problems in eight additional new areas. The objectives of computational benchmark work and the procedures used by the committee in pursuing the objectives are outlined in the original edition of the benchmark book (ANL-7416, February, 1968). The members of the committee who have made contributions to Supplement No. 2 are listed below followed by the contributors to the earlier editions of the benchmark book.

  15. IL-15 expression on RA synovial fibroblasts promotes B cell survival.

    Directory of Open Access Journals (Sweden)

    Marta Benito-Miguel

    Full Text Available INTRODUCTION: The purpose of this study was to examine the role of RA Synovial Fibroblast (RASFib IL-15 expression on B cell survival. METHODS: Magnetically sorted peripheral blood memory B cells from 15 healthy subjects were cocultured with RASFib. RESULTS: RASFib constitutively expressed membrane IL-15. Survival of isolated B cells cultured for 6 days, below 5%, was extended in coculture with RASFib to 52+/-8% (p<0.001. IL-15 neutralizing agents but not isotype controls, reduced this rate to 31+/-6% (p<0.05. Interestingly, rhIL-15 had no effect on isolated B cells but significantly increased their survival in coculture with RASFib. In parallel, B cell IL-15R chains were upregulated in cocultures. BAFF and VCAM-1, that are expressed on RASFib, were tested as potential candidates involved in upregulating B cell IL-15R. Culture of B cells in the presence of rhBAFF or rhVCAM-1 resulted in significantly increased survival, together with upregulation of all three IL-15R chains; in parallel, rhIL-15 potentiated the anti-apoptotic effect of BAFF and VCAM-1. Both BAFF and VCAM-1 neutralizing agents downmodulated the effect of RASFib on B cell survival and IL-15R expression. In parallel, rhIL-15 had a lower effect on the survival of B cells cocultured with RASFib in the presence of BAFF or VCAM-1 neutralizing agents. Peripheral blood B cells from 15 early RA patients demonstrated an upregulated IL-15R and increased survival in cocultures. CONCLUSION: IL-15 expression on RASFib significantly contributes to the anti-apoptotic effect of RASFib on B cells. IL-15 action is facilitated by BAFF and VCAM-1 expressed on RASFib, through an upregulation of IL-15R chains.

  16. Clinicopathological features of aggressive B-cell lymphomas including B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell and Burkitt lymphomas: a study of 44 patients from Argentina.

    Science.gov (United States)

    Bürgesser, María Virginia; Gualco, Gabriela; Diller, Ana; Natkunam, Yasodha; Bacchi, Carlos E

    2013-06-01

    Aggressive B-cell lymphomas incorporate a wide spectrum of lymphomas that pose challenges in diagnosis as well as treatment. We evaluated the clinicopathological features of 44 patients with aggressive B-cell lymphomas which were classified into 3 groups based on the World Health Organization 2008 classification as follows: including 30 cases of diffuse large B-cell lymphoma (DLBCL), 8 cases of Burkitt lymphoma (BL) and 6 cases of B-cell lymphoma, unclassifiable, with features intermediate between Burkitt lymphoma and diffuse large B-cell lymphoma (BCLU). Male predominance was observed in BL and BCLU groups and the mean age varied from 29 years in BL, 61 years in DLBCL and 70 years in BCLU. Patients with BCLU presented at more advanced stages and had a higher international prognostic index. By immunohistochemistry, they shared characteristics of both BL (including more frequent expression of SOX11) and DLBCL. FISH analyses showed three cases with more than one rearrangement: one MYC/BCL2 and two BCL2/BCL6, in addition to which one case with BCL2/IGH translocation and another with MYC rearrangement were also detected. The mean follow-up survival time of BCLU was 6.6 months, which was significantly shorter in comparison to DLBCL (31 months) and BL (30 months), respectively. The importance of recognizing this BCLU group relies on its different clinical course, poor prognosis and shorter survival than DLBCL and BL. An accurate diagnosis is critical for risk stratification and to improve therapeutic approaches and outcomes.

  17. Benchmarks

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  18. High-throughput epitope identification for snakebite antivenom

    DEFF Research Database (Denmark)

    Engmark, Mikael; De Masi, Federico; Laustsen, Andreas Hougaard;

    Insight into the epitopic recognition pattern for polyclonal antivenoms is a strong tool for accurate prediction of antivenom cross-reactivity and provides a basis for design of novel antivenoms. In this work, a high-throughput approach was applied to characterize linear epitopes in 966 individua...... toxins from pit vipers (Crotalidae) using the ICP Crotalidae antivenom. Due to an abundance of snake venom metalloproteinases and phospholipase A2s in the venoms used for production of the investigated antivenom, this study focuses on these toxin families.......Insight into the epitopic recognition pattern for polyclonal antivenoms is a strong tool for accurate prediction of antivenom cross-reactivity and provides a basis for design of novel antivenoms. In this work, a high-throughput approach was applied to characterize linear epitopes in 966 individual...

  19. T-dependent B-cell activation is signalled by an early increase in potassium influx

    DEFF Research Database (Denmark)

    Owens, T; Kaplan, J G

    1982-01-01

    (previously demonstrated when B and T lymphocytes were separately stimulated) also occurs when B cells are stimulated through cooperation with mitogen-activated T cells, and is also detectable early in culture. T-dependent activation of B cells is therefore detectable considerably earlier than by conventional...

  20. DEFECTS IN INSULIN-SECRETION IN NIDDM - B-CELL GLUCOSE INSENSITIVITY OR GLUCOSE TOXICITY

    NARCIS (Netherlands)

    VANHAEFTEN, TW

    1993-01-01

    In NIDDM, first-phase insulin release to glucose is (almost) absent. However, in contrast to older studies which suggested that in NIDDM the B-cell is ''blind'' for glucose, recent evidence indicates that the B-cell is not insensitive for glucose as far as second phase release is concerned. This sug

  1. Superenhancer reprogramming drives a B-cell-epithelial transition and high-risk leukemia.

    Science.gov (United States)

    Hu, Yeguang; Zhang, Zhihong; Kashiwagi, Mariko; Yoshida, Toshimi; Joshi, Ila; Jena, Nilamani; Somasundaram, Rajesh; Emmanuel, Akinola Olumide; Sigvardsson, Mikael; Fitamant, Julien; El-Bardeesy, Nabeel; Gounari, Fotini; Van Etten, Richard A; Georgopoulos, Katia

    2016-09-01

    IKAROS is required for the differentiation of highly proliferative pre-B-cell precursors, and loss of IKAROS function indicates poor prognosis in precursor B-cell acute lymphoblastic leukemia (B-ALL). Here we show that IKAROS regulates this developmental stage by positive and negative regulation of superenhancers with distinct lineage affiliations. IKAROS defines superenhancers at pre-B-cell differentiation genes together with B-cell master regulators such as PAX5, EBF1, and IRF4 but is required for a highly permissive chromatin environment, a function that cannot be compensated for by the other transcription factors. IKAROS is also highly enriched at inactive enhancers of genes normally expressed in stem-epithelial cells. Upon IKAROS loss, expression of pre-B-cell differentiation genes is attenuated, while a group of extralineage transcription factors that are directly repressed by IKAROS and depend on EBF1 relocalization at their enhancers for expression is induced. LHX2, LMO2, and TEAD-YAP1, normally kept separate from native B-cell transcription regulators by IKAROS, now cooperate directly with them in a de novo superenhancer network with its own feed-forward transcriptional reinforcement. Induction of de novo superenhancers antagonizes Polycomb repression and superimposes aberrant stem-epithelial cell properties in a B-cell precursor. This dual mechanism of IKAROS regulation promotes differentiation while safeguarding against a hybrid stem-epithelial-B-cell phenotype that underlies high-risk B-ALL.

  2. B cells assist allograft rejection in the deficiency of protein kinase c-theta.

    Science.gov (United States)

    Yan, Wenwei; Xu, Rui; Ma, Lian Li; Han, Wei; Geevarghese, Sunil K; Williams, Phillip E; Sciammas, Roger; Chong, Anita S; Yin, Deng Ping

    2013-09-01

    We have previously shown that mice deficient in protein kinase C theta (PKCθ) have the ability to reject cardiac allografts, but are susceptible to tolerance induction. Here we tested role of B cells in assisting alloimmune responses in the absence of PKCθ. Mouse cardiac allograft transplantations were performed from Balb/c (H-2d) to PKCθ knockout (PKCθ(-/-)), PKCθ and B cell double-knockout (PBDK, H-2b) mice and wild-type (WT) C57BL/6 (H-2b) mice. PBDK mice spontaneously accepted the allografts with the inhibition of NF-κB activation in the donor cardiac allograft. Anti-B cell antibody (rituximab) significantly delayed allograft rejection in PKCθ(-/-), but not in WT mice. Co-transfer of PKCθ(-/-) T plus PKCθ(-/-) B cells or primed sera triggered allograft rejection in Rag1(-/-) mice, and only major histocompatibility complex class II-enriched B cells, but not class I-enriched B cells, were able to promote rejection. This, together with the inability of PKCθ(-/-) and CD28(-/-) double-deficient (PCDK) mice to acutely reject allografts, suggested that an effective cognate interaction between PKCθ(-/-) T and B cells for acute rejection is CD28 molecule dependent. We conclude that T-B cell interactions synergize with PKCθ(-/-) T cells to mediate acute allograft rejection.

  3. Atypical and classical memory B cells produce Plasmodium falciparum neutralizing antibodies

    DEFF Research Database (Denmark)

    Muellenbeck, Matthias F; Ueberheide, Beatrix; Amulic, Borko;

    2013-01-01

    . We show at the single cell level that natural Pf infection induces the development of classical memory B cells (CM) and atypical memory B cells (AtM) that produce broadly neutralizing antibodies against blood stage Pf parasites. CM and AtM contribute to anti-Pf serum IgG production, but only AtM show...

  4. Identification of a negative regulatory role for spi-C in the murine B cell lineage.

    Science.gov (United States)

    Li, Stephen K H; Solomon, Lauren A; Fulkerson, Patricia C; DeKoter, Rodney P

    2015-04-15

    Spi-C is an E26 transformation-specific family transcription factor that is highly related to PU.1 and Spi-B. Spi-C is expressed in developing B cells, but its function in B cell development and function is not well characterized. To determine whether Spi-C functions as a negative regulator of Spi-B (encoded by Spib), mice were generated that were germline knockout for Spib and heterozygous for Spic (Spib(-/-)Spic(+/-)). Interestingly, loss of one Spic allele substantially rescued B cell frequencies and absolute numbers in Spib(-/-) mouse spleens. Spib(-/-)Spic(+/-) B cells had restored proliferation compared with Spib(-/-) B cells in response to anti-IgM or LPS stimulation. Investigation of a potential mechanism for the Spib(-/-)Spic(+/-) phenotype revealed that steady-state levels of Nfkb1, encoding p50, were elevated in Spib(-/-)Spic(+/-) B cells compared with Spib(-/-) B cells. Spi-B was shown to directly activate the Nfkb1 gene, whereas Spi-C was shown to repress this gene. These results indicate a novel role for Spi-C as a negative regulator of B cell development and function.

  5. Study of BKM120 & Rituximab in Patients With Relapsed or Refractory Indolent B-Cell Lymphoma

    Science.gov (United States)

    2016-06-14

    Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Splenic Marginal Zone Lymphoma; Waldenström Macroglobulinemia

  6. Identification of a negative regulatory role for spi-C in the murine B cell lineage.

    Science.gov (United States)

    Li, Stephen K H; Solomon, Lauren A; Fulkerson, Patricia C; DeKoter, Rodney P

    2015-04-15

    Spi-C is an E26 transformation-specific family transcription factor that is highly related to PU.1 and Spi-B. Spi-C is expressed in developing B cells, but its function in B cell development and function is not well characterized. To determine whether Spi-C functions as a negative regulator of Spi-B (encoded by Spib), mice were generated that were germline knockout for Spib and heterozygous for Spic (Spib(-/-)Spic(+/-)). Interestingly, loss of one Spic allele substantially rescued B cell frequencies and absolute numbers in Spib(-/-) mouse spleens. Spib(-/-)Spic(+/-) B cells had restored proliferation compared with Spib(-/-) B cells in response to anti-IgM or LPS stimulation. Investigation of a potential mechanism for the Spib(-/-)Spic(+/-) phenotype revealed that steady-state levels of Nfkb1, encoding p50, were elevated in Spib(-/-)Spic(+/-) B cells compared with Spib(-/-) B cells. Spi-B was shown to directly activate the Nfkb1 gene, whereas Spi-C was shown to repress this gene. These results indicate a novel role for Spi-C as a negative regulator of B cell development and function. PMID:25769919

  7. EBV-positive diffuse large B-cell lymphoma of the elderly

    NARCIS (Netherlands)

    C.Y. Ok (Chi Young); T.G. Papathomas (Thomas ); L.J. Medeiros (L. Jeffrey); K.H. Young (Ken)

    2013-01-01

    textabstractEpstein-Barr virus (EBV) positive diffuse large B-cell lymphoma (DLBCL) of the elderly, initially described in 2003, is a provisional entity in the 2008World Health Organization classification system and is defined as an EBV-positive monoclonal large B-cell proliferation that occurs in p

  8. A NOVel ELISPOT assay to quantify HLA-specific B cells in HLA-immunized individuals

    NARCIS (Netherlands)

    Heidt, S.; Roelen, D.L.; Vaal, Y.J. de; Kester, M.G.; Eijsink, C.; Thomas, S.; Besouw, N.M. van; Volk, H.D.; Weimar, W.; Claas, F.H.; Mulder, A.

    2012-01-01

    Quantification of the humoral alloimmune response is generally achieved by measuring serum HLA antibodies, which provides no information about the cells involved in the humoral immune response. Therefore, we have developed an HLA-specific B-cell ELISPOT assay allowing for quantification of B cells p

  9. Novel Function of TNF Cytokines in Regulating Bone Marrow B Cell Survival

    Institute of Scientific and Technical Information of China (English)

    Min Zhang; King-Hung Ko; Queenie Lai Kwan Lam; Cherry Kam Chun Lo; Daniel Jia Lin Xu; Lijun Shen; Bojian Zheng; Gopesh Srivastava; Liwei Lu

    2004-01-01

    Two newly identified tumor necrosis factor (TNF) family cytokines, B cell activation factor from the TNF family (BAFF) and a proliferation-inducing ligand (APRIL), have recently been shown to enhance the maturation and survival of peripheral B cells. However, whether BAFF and APRIL are expressed in the bone marrow (BM) microenvironment and if these two cytokines modulate early B cell development remain unclear.In the present study, we have detected the abundant expression of BAFF and APRIL transcripts in BM non-lymphoid cells. Low levels of BAFF and APRIL mRNA are also found in developing B cells. Furthermore,we have determined the expression patterns of BAFF receptors during B lymphopoiesis. In cultures, both recombinant BAFF and APRIL significantly promote the survival of precursor B cells whereas only BAFF can suppress apoptosis of immature B cells. These findings suggest that BAFF and APRIL, in addition to their well established role in regulating peripheral B cell growth, can modulate the survival of developing B cells in the BM. Cellular & Molecular Immunology. 2004;1(6):447-453.

  10. Recruitment and selection of marginal zone B cells is independent of exogenous antigens

    NARCIS (Netherlands)

    Dammers, PM; Kroese, FGM

    2005-01-01

    Marginal zone B (MZ-B) cells of the spleen contribute significantly to the immunity against invasive infections with polysaccharide-encapsulated bacteria. Recent evidence indicates that recruitment and selection of MZ-B cells occurs on the basis of positive selection constraints that likely operate

  11. Selective loss of B-cell phenotype in lymphocyte predominant Hodgkin lymphoma.

    NARCIS (Netherlands)

    Tedoldi, S.; Mottok, A.; Ying, J.; Paterson, J.C.; Cui, Y.; Facchetti, F.; Krieken, J.H.J.M. van; Ponzoni, M.; Ozkal, S.; Masir, N.; Natkunam, Y.; Pileri, S.; Hansmann, M.L.; Mason, D.; Tao, Q.; Marafioti, T.

    2007-01-01

    The neoplastic Reed-Sternberg cells characteristic of classical Hodgkin's lymphoma (cHL) are of B-cell origin but they almost always show striking loss of a range of B-cell-associated molecules. In contrast, the neoplastic cells found in lymphocyte predominant Hodgkin's lymphoma (LPHL) (L&H cells) a

  12. Expression pattern of FCRL (FREB, FcRX) in normal and neoplastic human B cells.

    Science.gov (United States)

    Masir, Noraidah; Jones, Margaret; Pozzobon, Michela; Marafioti, Teresa; Volkova, Olga Y; Mechetina, Ludmila V; Hansmann, Martin-Leo; Natkunam, Yasodha; Taranin, Alexander V; Mason, David Y

    2004-11-01

    FCRL (also known as FREB and FcRX) is a recently described member of the family of Fc receptors for immunoglobulin G (IgG). In the present study we analysed its expression in normal and neoplastic lymphoid tissue using immunohistochemical techniques. FCRL was preferentially expressed in a proportion of germinal centre cells and, more weakly, in mantle zone B cells. In addition, strong labelling was observed in marginal zone B cells in the spleen, representing one of the few markers for this cell type. The majority of cases of small B-cell lymphoma, diffuse large B-cell lymphoma and lymphocyte predominance Hodgkin's disease were positive for FCRL. However, the number of positive cells varied widely, and in consequence we could not define a cut-off that distinguished subsets of diffuse large B-cell lymphoma. Our results also showed that FCRL tended to be negative in T-cell-rich B-cell lymphoma and in classical Hodgkin's disease. FCRL may therefore represent a novel marker for normal B cells (e.g. splenic marginal zone cells) and may also be useful as a potential marker of B-cell neoplasms. PMID:15491296

  13. Regulatory B cells present in lymph nodes draining a murine tumor

    Directory of Open Access Journals (Sweden)

    Andrea Maglioco

    2014-06-01

    Full Text Available In cancer, B cells have been classically associated with antibody secretion, antigen presentation and T cell activation. However, a possible role for B lymphocytes in impairing antitumor response and collaborating with tumor growth has been brought into focus. Recent reports have described the capacity of B cells to negatively affect immune responses in autoimmune diseases. The highly immunogenic mouse tumor MCC loses its immunogenicity and induces systemic immune suppression and tolerance as it grows. We have previously demonstrated that MCC growth induces a distinct and progressive increase in B cell number and proportion in the tumor draining lymph nodes (TDLN, as well as a less prominent increase in T regulatory cells. The aim of this research was to study B cell characteristics and function in the lymph node draining MCC tumor and to analyze whether these cells may be playing a role in suppressing antitumor response and favoring tumor progression. Results indicate that B cells from TDLN expressed increased CD86 and MHCII co-stimulatory molecules indicating activated phenotype, as well as intracellular IL-10, FASL and Granzyme B, molecules with regulatory immunosuppressive properties. Additionally, B cells showed high inhibitory upon T cell proliferation ex vivo, and a mild capacity to secrete antibodies. Our conclusion is that even when evidence of B cell-mediated activity of the immune response is present, B cells from TDLN exhibit regulatory phenotype and inhibitory activity, probably contributing to the state of immunological tolerance characteristic of the advanced tumor condition.

  14. PageRank Pipeline Benchmark: Proposal for a Holistic System Benchmark for Big-Data Platforms

    CERN Document Server

    Dreher, Patrick; Hill, Chris; Gadepally, Vijay; Kuszmaul, Bradley; Kepner, Jeremy

    2016-01-01

    The rise of big data systems has created a need for benchmarks to measure and compare the capabilities of these systems. Big data benchmarks present unique scalability challenges. The supercomputing community has wrestled with these challenges for decades and developed methodologies for creating rigorous scalable benchmarks (e.g., HPC Challenge). The proposed PageRank pipeline benchmark employs supercomputing benchmarking methodologies to create a scalable benchmark that is reflective of many real-world big data processing systems. The PageRank pipeline benchmark builds on existing prior scalable benchmarks (Graph500, Sort, and PageRank) to create a holistic benchmark with multiple integrated kernels that can be run together or independently. Each kernel is well defined mathematically and can be implemented in any programming environment. The linear algebraic nature of PageRank makes it well suited to being implemented using the GraphBLAS standard. The computations are simple enough that performance predictio...

  15. B-cell clonality in the liver of hepatitis C virus-infected patients

    Institute of Scientific and Technical Information of China (English)

    He-Bin Fan; You-Fu Zhu; An-Shen Chen; Mu-Xiu Zhou; Fu-Ming Yan; Xiao-Ju Ma; Hao Zhou

    2009-01-01

    AIM: The association of hepatitis C virus (HCV) infection with type Ⅱ mixed cryoglobulinemia is well established, but the role of HCV in B-cell lymphoma remains controversial. In patients with HCV infection, B-cell clonal expansions have been detected in peripheral blood and bone marrow, and a high been documented. Liver biopsies in chronic HCV infection frequently show portal lymphoid infiltrates with features of B follicles, whose clonality has not yet been investigated. The object of this study was to determine the frequency of liver-infiltrating monoclonal B-cells in 40 patients with HCV infection. METHODS: Eight hundred and forty-eight patients were studied prospectively, including 40 HCV-positive patients and 808 patients with chronic hepatitis B virus (HBV) infection. Immunohistochemical study for B- and T-cell markers was performed on the paraffin-embedded liver tissue sections. The clonality of lymphoid B-cells was tested using a polymerase chain reaction (PCR) approach designed to identify immunoglobulin heavy chain gene ( IgH) rearrangements. RESULTS: Liver-infiltrating monoclonal B-cells were detected in the liver for 4 (10%) of 40 HCV-positive patients but were present in only 3 (0.37%) of 808 liver biopsy specimens with chronic HBV infection. Chi-square testing showed that the monoclonal B-cells infiltration in the liver was more frequent in the HCV-infected patients ( P = 0.000). A clonal IgH rearrangement was detected in 5 (71.4%) of 7 liver biopsy specimens with monoclonal B-cells infiltration. In 2 of 5 patients with both a clonal B-cell expansion and monoclonal B-cells infiltration in the liver, a definite B-cell malignancy was finally diagnosed. CONCLUSION: Liver-infiltrating monoclonal B-cells are detected in the liver of patients with chronic HCV and HBV infection. A high percentage of patients with monoclonal B-cells infiltration and B-cell clonality in the liver were finally diagnosed as having a definite B-cell malignancy.

  16. Computational elucidation of potential antigenic CTL epitopes in Ebola virus.

    Science.gov (United States)

    Dikhit, Manas R; Kumar, Santosh; Vijaymahantesh; Sahoo, Bikash R; Mansuri, Rani; Amit, Ajay; Yousuf Ansari, Md; Sahoo, Ganesh C; Bimal, Sanjiva; Das, Pradeep

    2015-12-01

    Cell-mediated immunity is important for the control of Ebola virus infection. We hypothesized that those HLA A0201 and HLA B40 restricted epitopes derived from Ebola virus proteins, would mount a good antigenic response. Here we employed an immunoinformatics approach to identify specific 9mer amino acid which may be capable of inducing a robust cell-mediated immune response in humans. We identified a set of 28 epitopes that had no homologs in humans. Specifically, the epitopes derived from NP, RdRp, GP and VP40 share population coverage of 93.40%, 84.15%, 74.94% and 77.12%, respectively. Based on the other HLA binding specificity and population coverage, seven novel promiscuous epitopes were identified. These 7 promiscuous epitopes from NP, RdRp and GP were found to have world-wide population coverage of more than 95% indicating their potential significance as useful candidates for vaccine design. Epitope conservancy analysis also suggested that most of the peptides are highly conserved (100%) in other virulent Ebola strain (Mayinga-76, Kikwit-95 and Makona-G3816- 2014) and can therefore be further investigated for their immunological relevance and usefulness as vaccine candidates.

  17. Strategic Use of Epitope Matching to Improve Outcomes.

    Science.gov (United States)

    Wiebe, Chris; Nickerson, Peter

    2016-10-01

    Understanding the events leading to allorecognition and the subsequent effector pathways engaged is key for the development of strategies to prolong graft survival. Optimizing patient outcomes will require 2 major advancements: (1) minimizing premature death with a functioning graft in the patients with stable graft function, and (2) maximizing graft survival by avoiding the aforementioned allorecognition. This necessitates personalized immunosuppression to avoid known metabolic side effects, risk for infection, and malignancy, while holding the alloimmune system in check. Since the beginning of transplant a key strategy to achieve this goal is to minimize HLA mismatching between donor and recipient. What has not evolved is any refinement in our evaluation of HLA relatedness between donor and recipient when HLA mismatch exists. Donor-recipient HLA mismatch at the amino acid level can now be determined. These mismatches serve as potential epitopes for de novo donor specific antibody development and correlate with late rejection and graft loss. It is in this context that HLA epitope analysis is considered as a strategy to permit safe immunosuppression minimization to improve patient outcomes through: (1) improved allocation schemes that favor donor-recipient pairs with a low HLA epitope mismatch load (especially at the class II loci) or avoiding specific epitope mismatches known to be highly immunogenic and (2) immunosuppressive minimization in patients with low epitope mismatch loads or without highly immunogenic epitope mismatches.

  18. Antigen-specific monoclonal antibodies isolated from B cells expressing constitutively active STAT5.

    Directory of Open Access Journals (Sweden)

    Ferenc A Scheeren

    Full Text Available BACKGROUND: Fully human monoclonal antibodies directed against specific pathogens have a high therapeutic potential, but are difficult to generate. METHODOLOGY/PRINCIPAL FINDINGS: Memory B cells were immortalized by expressing an inducible active mutant of the transcription factor Signal Transducer and Activator of Transcription 5 (STAT5. Active STAT5 inhibits the differentiation of B cells while increasing their replicative life span. We obtained cloned B cell lines, which produced antibodies in the presence of interleukin 21 after turning off STAT5. We used this method to obtain monoclonal antibodies against the model antigen tetanus toxin. CONCLUSIONS/SIGNIFICANCE: Here we describe a novel and relatively simple method of immortalizing antigen-specific human B cells for isolation of human monoclonal antibodies. These results show that STAT5 overexpression can be employed to isolate antigen specific antibodies from human memory B cells.

  19. B cells in the pathophysiology of autoimmune neurological disorders: a credible therapeutic target.

    Science.gov (United States)

    Dalakas, Marinos C

    2006-10-01

    There is evidence that B cells are involved in the pathophysiology of many neurological diseases, either in a causative or contributory role, via production of autoantibodies, cytokine secretion, or by acting as antigen-presenting cells leading to T cell activation. Clonal expansion of B cells either in situ or intrathecally and circulating autoantibodies are critical elements in multiple sclerosis (MS), Devic's disease, paraneoplastic central nervous system disorders, stiff-person syndrome, myasthenia gravis, autoimmune demyelinating neuropathies and dermatomyositis. The pathogenic role of B cells and autoantibodies in central and peripheral nervous system disorders, as reviewed here, provides a rationale for investigating whether depletion of B cells with new agents can improve clinical symptomatology and, potentially, restore immune function. Preliminary results from several clinical studies and case reports suggest that B cell depletion may become a viable alternative approach to the treatment of autoimmune neurological disorders.

  20. Regulated selection of germinal-center cells into the memory B cell compartment.

    Science.gov (United States)

    Shinnakasu, Ryo; Inoue, Takeshi; Kometani, Kohei; Moriyama, Saya; Adachi, Yu; Nakayama, Manabu; Takahashi, Yoshimasa; Fukuyama, Hidehiro; Okada, Takaharu; Kurosaki, Tomohiro

    2016-07-01

    Despite the importance of memory B cells in protection from reinfection, how such memory cells are selected and generated during germinal-center (GC) reactions remains unclear. We found here that light-zone (LZ) GC B cells with B cell antigen receptors (BCRs) of lower affinity were prone to enter the memory B cell pool. Mechanistically, cells in this memory-prone fraction had higher expression of the transcriptional repressor Bach2 than that of their counterparts with BCRs of higher affinity. Haploinsufficiency of Bach2 resulted in reduced generation of memory B cells, independently of suppression of the gene encoding the transcription factor Blimp-1. Bach2 expression in GC cells was inversely correlated with the strength of help provided by T cells. Thus, we propose an instructive model in which weak help from T cells maintains relatively high expression of Bach2, which predisposes GC cells to enter the memory pool.