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Sample records for antiviral antibody reactivity

  1. Anti-Viral Antibody Profiling by High Density Protein Arrays

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    Bian, Xiaofang; Wiktor, Peter; Kahn, Peter; Brunner, Al; Khela, Amritpal; Karthikeyan, Kailash; Barker, Kristi; Yu, Xiaobo; Magee, Mitch; Wasserfall, Clive H.; Gibson, David; Rooney, Madeleine E; Qiu, Ji; LaBaer, Joshua

    2015-01-01

    Viral infections elicit anti-viral antibodies and have been associated with various chronic diseases. Detection of these antibodies can facilitate diagnosis, treatment of infection and understanding of the mechanisms of virus associated diseases. In this work, we assayed anti-viral antibodies using a novel high density-nucleic acid programmable protein array (HD-NAPPA) platform. Individual viral proteins were expressed in situ directly from plasmids encoding proteins in an array of microscopic reaction chambers. Quality of protein display and serum response was assured by comparing intra- and inter- array correlation within or between printing batches with average correlation coefficients of 0.91 and 0.96, respectively. HD-NAPPA showed higher signal to background (S/B) ratio compared with standard NAPPA on planar glass slides and ELISA. Antibody responses to 761 antigens from 25 different viruses were profiled among patients with juvenile idiopathic arthritis (JIA) and type 1 diabetes (T1D). Common as well as unique antibody reactivity patterns were detected between patients and healthy controls. We believe HD-viral-NAPPA will enable the study of host-pathogen interactions at unprecedented dimensions and elucidate the role of pathogen infections in disease development. PMID:25758251

  2. Effective inhibition of viral reproduction by hydrophobised antiviral antibodies.

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    Kabanov, A V; Ovcharenko, A V; Melik-Nubarov, N S; Bannikov, A I; Lisok, T P; Klyushnenkova, E V; Cherchenko, N G; Alakhov VYu; Levashov, A V; Kiselev, V I

    1990-01-01

    A method is proposed for the inhibition of viral reproduction in cells by means of fatty-acylated antiviral antibodies which, in contrast to the unmodified antibodies, have the ability to enter the cells. The potential of this technique is demonstrated in experiments involving inhibition of the reproduction of various strains of influenza virus and respiratory syncytial virus.

  3. Monoclonal antibodies reactive with hairy cell leukemia

    NARCIS (Netherlands)

    Visser, L; Shaw, A; Slupsky, J; Vos, H; Poppema, S

    Monoclonal antibodies reactive with hairy cell leukemia were developed to aid in the diagnosis of this subtype of B cell chronic lymphocytic leukemia and to gain better insight into the origin of hairy cells. Three antibodies were found to be of value in the diagnosis of hairy cell leukemia.

  4. Monoclonal antibodies reactive with hairy cell leukemia

    NARCIS (Netherlands)

    Visser, L; Shaw, A; Slupsky, J; Vos, H; Poppema, S

    1989-01-01

    Monoclonal antibodies reactive with hairy cell leukemia were developed to aid in the diagnosis of this subtype of B cell chronic lymphocytic leukemia and to gain better insight into the origin of hairy cells. Three antibodies were found to be of value in the diagnosis of hairy cell leukemia. Antibod

  5. Lipophilicity is a key factor to increase the antiviral activity of HIV neutralizing antibodies.

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    Augusto, Marcelo T; Hollmann, Axel; Troise, Fulvia; Veiga, Ana S; Pessi, Antonello; Santos, Nuno C

    2017-04-01

    The HIV broadly neutralizing antibody 2F5 targets the transiently exposed epitope in the membrane proximal external region (MPER) of HIV-1 gp41, by a two-step mechanism involving the viral membrane and this viral glycoprotein. It was recently shown that 2F5 conjugation with a cholesterol moiety outside of the antibody paratope substantially increases its antiviral activity. Additionally, the antiviral activity of D5, a human antibody that binds to the N-terminal heptad repeat (NHR) of gp41 and lacks membrane binding, was boosted by the same cholesterol conjugation. In this work, we evaluated the membrane affinity of both antibodies towards membranes of different compositions, using surface plasmon resonance. A correlation was found between membrane affinity and antiviral activity against HIV-1. We propose that the conjugation of cholesterol to 2F5 or D5 allows a higher degree of antibody pre-concentration at the viral membrane. This way, the antibodies become more available to bind efficiently to the gp41 epitope, blocking viral fusion faster than the unconjugated antibody. These results set up a relevant strategy to improve the rational design of therapeutic antibodies against HIV.

  6. Development of a novel monoclonal antibody with reactivity to a wide range of Venezuelan equine encephalitis virus strains

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    Phelps Amanda L

    2009-11-01

    Full Text Available Abstract Background There is currently a requirement for antiviral therapies capable of protecting against infection with Venezuelan equine encephalitis virus (VEEV, as a licensed vaccine is not available for general human use. Monoclonal antibodies are increasingly being developed as therapeutics and are potential treatments for VEEV as they have been shown to be protective in the mouse model of disease. However, to be truly effective, the antibody should recognise multiple strains of VEEV and broadly reactive monoclonal antibodies are rarely and only coincidentally isolated using classical hybridoma technology. Results In this work, methods were developed to reliably derive broadly reactive murine antibodies. A phage library was created that expressed single chain variable fragments (scFv isolated from mice immunised with multiple strains of VEEV. A broadly reactive scFv was identified and incorporated into a murine IgG2a framework. This novel antibody retained the broad reactivity exhibited by the scFv but did not possess virus neutralising activity. However, the antibody was still able to protect mice against VEEV disease induced by strain TrD when administered 24 h prior to challenge. Conclusion A monoclonal antibody possessing reactivity to a wide range of VEEV strains may be of benefit as a generic antiviral therapy. However, humanisation of the murine antibody will be required before it can be tested in humans. Crown Copyright © 2009

  7. Antiviral Therapy by HIV-1 Broadly Neutralizing and Inhibitory Antibodies

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    Zhiqing Zhang

    2016-11-01

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 infection causes acquired immune deficiency syndrome (AIDS, a global epidemic for more than three decades. HIV-1 replication is primarily controlled through antiretroviral therapy (ART but this treatment does not cure HIV-1 infection. Furthermore, there is increasing viral resistance to ART, and side effects associated with long-term therapy. Consequently, there is a need of alternative candidates for HIV-1 prevention and therapy. Recent advances have discovered multiple broadly neutralizing antibodies against HIV-1. In this review, we describe the key epitopes on the HIV-1 Env protein and the reciprocal broadly neutralizing antibodies, and discuss the ongoing clinical trials of broadly neutralizing and inhibitory antibody therapy as well as antibody combinations, bispecific antibodies, and methods that improve therapeutic efficacy by combining broadly neutralizing antibodies (bNAbs with latency reversing agents. Compared with ART, HIV-1 therapeutics that incorporate these broadly neutralizing and inhibitory antibodies offer the advantage of decreasing virus load and clearing infected cells, which is a promising prospect in HIV-1 prevention and treatment.

  8. Antiviral Therapy by HIV-1 Broadly Neutralizing and Inhibitory Antibodies.

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    Zhang, Zhiqing; Li, Shaowei; Gu, Ying; Xia, Ningshao

    2016-11-18

    Human immunodeficiency virus type 1 (HIV-1) infection causes acquired immune deficiency syndrome (AIDS), a global epidemic for more than three decades. HIV-1 replication is primarily controlled through antiretroviral therapy (ART) but this treatment does not cure HIV-1 infection. Furthermore, there is increasing viral resistance to ART, and side effects associated with long-term therapy. Consequently, there is a need of alternative candidates for HIV-1 prevention and therapy. Recent advances have discovered multiple broadly neutralizing antibodies against HIV-1. In this review, we describe the key epitopes on the HIV-1 Env protein and the reciprocal broadly neutralizing antibodies, and discuss the ongoing clinical trials of broadly neutralizing and inhibitory antibody therapy as well as antibody combinations, bispecific antibodies, and methods that improve therapeutic efficacy by combining broadly neutralizing antibodies (bNAbs) with latency reversing agents. Compared with ART, HIV-1 therapeutics that incorporate these broadly neutralizing and inhibitory antibodies offer the advantage of decreasing virus load and clearing infected cells, which is a promising prospect in HIV-1 prevention and treatment.

  9. The effect of infliximab on antiviral antibody profiles in patients with rheumatoid arthritis.

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    Kaufman, Ilana; Moscovici, Yolanda Braun; Abudi, Yair; Sofer, Denit; Mendelson, Ella; Balbir-Gurman, Alexandra; Caspi, Dan; Elkayam, Ori

    2010-01-01

    The duration of humoral immunity in patients treated with immunosuppressive drugs is poorly defined. The objective of the study was to investigate the effect of infliximab on the levels of antiviral antibodies against poliomyelitis, rubella and measles in rheumatoid arthritis (RA) patients. Fifty-two consecutive RA patients being treated with 3 mg/kg infliximab were prospectively studied. The antiviral antibody profiles for measles, rubella and three serotypes of poliomyelitis were tested on the day of the first infusion of infliximab and 6 months later. The study group comprised 36 women and 16 men (mean age 54 years, range 33-81) with a mean disease duration of 15 +/- 9 years. Forty-two (81%) patients were being treated with methotrexate and 22 (42%) were receiving prednisone. All patients had baseline protective levels of antibodies against measles and the three strains of polio, while 48 (92%) patients had protective antibodies against rubella. No significant change in the levels of antiviral antibodies was observed after 6 months of treatment with infliximab: from 3.67 at baseline to 3.87 IU/ml for measles, 169.50-197.0 IU/ml for rubella. No change was noticed for the geometric mean concentrations of antibodies against strains of poliomyelitis: 366-478 IU/ml for the Mahoney polio strain, 906-845 IU/ml for the MEF strain and 175-196 IU/ml for the Sauket strain. Patients with longstanding RA conserve long-term immunity to common viruses despite the use of immunosuppressive drugs. Levels of antiviral antibodies against measles, rubella and polio remain stable under treatment with infliximab.

  10. Dengue virus cell entry : Unraveling the role of antibodies, maturation status, and antiviral drugs

    NARCIS (Netherlands)

    Ayala Nunez, Vanesa

    2014-01-01

    Antibody-dependent enhancement (ADE) is thought to play a critical role in the exacerbation of dengue virus-induced disease during a heterologous re-infection. Pre-existing cross-reactive anti-dengue antibodies are generally believed to bind to the newly infecting DENV and target the antibody-virus

  11. Characterization of immobilization methods of antiviral antibodies in serum for electrochemical biosensors

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    Huy, Tran Quang, E-mail: huytq@nihe.org.vn [National Institute of Hygiene and Epidemiology (NIHE), No1 Yersin St., Hanoi (Viet Nam); International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST), No1 Dai Co Viet, Hanoi (Viet Nam); Hanh, Nguyen Thi Hong; Van Chung, Pham; Anh, Dang Duc; Nga, Phan Thi [National Institute of Hygiene and Epidemiology (NIHE), No1 Yersin St., Hanoi (Viet Nam); Tuan, Mai Anh, E-mail: tuanma-itims@mail.hut.edu.vn [International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST), No1 Dai Co Viet, Hanoi (Viet Nam)

    2011-06-01

    In this paper, we describes different methods to immobilize Japanese encephalitis virus (JEV) antibodies in human serum onto the interdigitated surface of a microelectrode sensor for optimizing electrochemical detection: (1) direct covalent binding to the silanized surface, (2) binding to the silanized surface via a cross-linker of glutaraldehyde (GA), (3) binding to glutaraldehyde/silanized surface via goat anti-human IgG polyclonal antibody and (4) binding to glutaraldehyde/silanized surface via protein A (PrA). Field emission scanning electron microscopy, Fourier transform infrared spectrometry, and fluorescence microscopy are used to verify the characteristics of antibodies on the interdigitated surface after the serum antibodies immobilization. The analyzed results indicate that the use of protein A is an effective choice for immobilization and orientation of antibodies in serum for electrochemical biosensors. This study provides an advantageous immobilization method of serum containing antiviral antibodies to develop electrochemical biosensors for preliminary screening of viruses in clinical samples from outbreaks.

  12. Cross-reactive anti-viral T cells increase prior to an episode of viral reactivation post human lung transplantation.

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    Thi H O Nguyen

    Full Text Available Human Cytomegalovirus (CMV reactivation continues to influence lung transplant outcomes. Cross-reactivity of anti-viral memory T cells against donor human leukocyte antigens (HLA may be a contributing factor. We identified cross-reactive HLA-A*02:01-restricted CMV-specific cytotoxic T lymphocytes (CTL co-recognizing the NLVPMVATV (NLV epitope and HLA-B27. NLV-specific CD8+ T cells were expanded for 13 days from 14 HLA-A*02:01/CMV seropositive healthy donors and 11 lung transplant recipients (LTR then assessed for the production of IFN-γ and CD107a expression in response to 19 cell lines expressing either single HLA-A or -B class I molecules. In one healthy individual, we observed functional and proliferative cross-reactivity in response to B*27:05 alloantigen, representing approximately 5% of the NLV-specific CTL population. Similar patterns were also observed in one LTR receiving a B27 allograft, revealing that the cross-reactive NLV-specific CTL gradually increased (days 13-193 post-transplant before a CMV reactivation event (day 270 and reduced to basal levels following viral clearance (day 909. Lung function remained stable with no acute rejection episodes being reported up to 3 years post-transplant. Individualized immunological monitoring of cross-reactive anti-viral T cells will provide further insights into their effects on the allograft and an opportunity to predict sub-clinical CMV reactivation events and immunopathological complications.

  13. Flavivirus-induced antibody cross-reactivity.

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    Mansfield, Karen L; Horton, Daniel L; Johnson, Nicholas; Li, Li; Barrett, Alan D T; Smith, Derek J; Galbraith, Sareen E; Solomon, Tom; Fooks, Anthony R

    2011-12-01

    Dengue viruses (DENV) cause countless human deaths each year, whilst West Nile virus (WNV) has re-emerged as an important human pathogen. There are currently no WNV or DENV vaccines licensed for human use, yet vaccines exist against other flaviviruses. To investigate flavivirus cross-reactivity, sera from a human cohort with a history of vaccination against tick-borne encephalitis virus (TBEV), Japanese encephalitis virus (JEV) and yellow fever virus (YFV) were tested for antibodies by plaque reduction neutralization test. Neutralization of louping ill virus (LIV) occurred, but no significant neutralization of Murray Valley encephalitis virus was observed. Sera from some individuals vaccinated against TBEV and JEV neutralized WNV, which was enhanced by YFV vaccination in some recipients. Similarly, some individuals neutralized DENV-2, but this was not significantly influenced by YFV vaccination. Antigenic cartography techniques were used to generate a geometric illustration of the neutralization titres of selected sera against WNV, TBEV, JEV, LIV, YFV and DENV-2. This demonstrated the individual variation in antibody responses. Most sera had detectable titres against LIV and some had titres against WNV and DENV-2. Generally, LIV titres were similar to titres against TBEV, confirming the close antigenic relationship between TBEV and LIV. JEV was also antigenically closer to TBEV than WNV, using these sera. The use of sera from individuals vaccinated against multiple pathogens is unique relative to previous applications of antigenic cartography techniques. It is evident from these data that notable differences exist between amino acid sequence identity and mapped antigenic relationships within the family Flaviviridae.

  14. Origin, diversity and maturation of human antiviral antibodies analyzed by high-throughput sequencing

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    Ponraj ePrabakaran

    2012-08-01

    Full Text Available Our understanding of how antibodies are generated and function could help develop effective vaccines and antibody-based therapeutics against viruses such as HIV-1, SARS Coronavirus (CoV, and Hendra and Nipah viruses (henipaviruses. Although broadly neutralizing antibodies (bnAbs against the HIV-1 were observed in patients, elicitation of such bnAbs remains a major challenge when compared to other viral targets. We previously hypothesized that HIV-1 could have evolved a strategy to evade the immune system due to absent or very weak binding of germline antibodies to the conserved epitopes that may not be sufficient to initiate and/or maintain an effective immune response. To further explore our hypothesis, we used the 454 sequence analysis of a large naïve library of human IgM antibodies which had been used for selecting antibodies against SARS Coronavirus (CoV receptor-binding domain (RBD, and soluble G proteins (sG of Hendra and Nipah viruses (henipaviruses. We found that the human IgM repertoires from the 454 sequencing have diverse germline usages, recombination patterns, junction diversity and a lower extent of somatic mutation. In this study, we identified germline intermediates of antibodies specific to HIV-1 and other viruses as observed in normal individuals, and compared their genetic diversity and somatic mutation level along with available structural and functional data. Further computational analysis will provide framework for understanding the underlying genetic and molecular determinants related to maturation pathways of antiviral bnAbs that could be useful for applying novel approaches to the design of effective vaccine immunogens and antibody-based therapeutics.

  15. Defining the recognition elements of Lewis Y-reactive antibodies.

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    Somdutta Saha

    Full Text Available Antibody response to carbohydrate antigens is often independent of T cells and the process of affinity/specificity improvement is considered strictly dependent on the germinal centers. Antibodies induced during a T cell-independent type 2 (TI-2 response are less variable and less functionally versatile than those induced with T cell help. The antigen specificity consequences of accumulation of somatic mutations in antibodies during TI-2 responses of Marginal Zone (MZ B cells is a fact that still needs explanation. Germline genes that define carbohydrate-reactive antibodies are known to sculpt antibody-combining sites containing innate, key side-chain contacts that define the antigen recognition step. However, substitutions associated with MZ B cell derived antibodies might affect the mobility and polyspecificity of the antibody. To examine this hypothesis, we analyzed antibodies reactive with the neolactoseries antigen Lewis Y (LeY to define the residue subset required for the reactive repertoire for the LeY antigen. Our molecular simulation studies of crystallographically determined and modeled antibody-LeY complexes suggests that the heavy-chain germline gene VH7183.a13.20 and the light-chain Vκ cr1 germline gene are sufficient to account for the recognition of the trisaccharide-H determinant Types 1-4, while the specificity for LeY is driven by the CDR3 backbone conformation of the heavy chain and not the side chain interactions. These results confirm that these monoclonals use germline-encoded amino acids to recognize simple carbohydrate determinants like trisaccharide-H but relies on somatic mutations in the periphery of the combining site to modify affinity for LeY through electrostatic interactions that leads to their optimized binding. These observations bring further attention to the role of mutations in T-cell independent antibodies to distinguish self from non-self carbohydrate antigens.

  16. Defining the Recognition Elements of Lewis Y-Reactive Antibodies

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    Saha, Somdutta; Pashov, Anastas; Siegel, Eric R.; Murali, Ramachandran; Kieber-Emmons, Thomas

    2014-01-01

    Antibody response to carbohydrate antigens is often independent of T cells and the process of affinity/specificity improvement is considered strictly dependent on the germinal centers. Antibodies induced during a T cell-independent type 2 (TI-2) response are less variable and less functionally versatile than those induced with T cell help. The antigen specificity consequences of accumulation of somatic mutations in antibodies during TI-2 responses of Marginal Zone (MZ) B cells is a fact that still needs explanation. Germline genes that define carbohydrate-reactive antibodies are known to sculpt antibody-combining sites containing innate, key side-chain contacts that define the antigen recognition step. However, substitutions associated with MZ B cell derived antibodies might affect the mobility and polyspecificity of the antibody. To examine this hypothesis, we analyzed antibodies reactive with the neolactoseries antigen Lewis Y (LeY) to define the residue subset required for the reactive repertoire for the LeY antigen. Our molecular simulation studies of crystallographically determined and modeled antibody-LeY complexes suggests that the heavy-chain germline gene VH7183.a13.20 and the light-chain Vκ cr1 germline gene are sufficient to account for the recognition of the trisaccharide-H determinant Types 1–4, while the specificity for LeY is driven by the CDR3 backbone conformation of the heavy chain and not the side chain interactions. These results confirm that these monoclonals use germline-encoded amino acids to recognize simple carbohydrate determinants like trisaccharide-H but relies on somatic mutations in the periphery of the combining site to modify affinity for LeY through electrostatic interactions that leads to their optimized binding. These observations bring further attention to the role of mutations in T-cell independent antibodies to distinguish self from non-self carbohydrate antigens. PMID:25117628

  17. Defining the recognition elements of Lewis Y-reactive antibodies.

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    Saha, Somdutta; Pashov, Anastas; Siegel, Eric R; Murali, Ramachandran; Kieber-Emmons, Thomas

    2014-01-01

    Antibody response to carbohydrate antigens is often independent of T cells and the process of affinity/specificity improvement is considered strictly dependent on the germinal centers. Antibodies induced during a T cell-independent type 2 (TI-2) response are less variable and less functionally versatile than those induced with T cell help. The antigen specificity consequences of accumulation of somatic mutations in antibodies during TI-2 responses of Marginal Zone (MZ) B cells is a fact that still needs explanation. Germline genes that define carbohydrate-reactive antibodies are known to sculpt antibody-combining sites containing innate, key side-chain contacts that define the antigen recognition step. However, substitutions associated with MZ B cell derived antibodies might affect the mobility and polyspecificity of the antibody. To examine this hypothesis, we analyzed antibodies reactive with the neolactoseries antigen Lewis Y (LeY) to define the residue subset required for the reactive repertoire for the LeY antigen. Our molecular simulation studies of crystallographically determined and modeled antibody-LeY complexes suggests that the heavy-chain germline gene VH7183.a13.20 and the light-chain Vκ cr1 germline gene are sufficient to account for the recognition of the trisaccharide-H determinant Types 1-4, while the specificity for LeY is driven by the CDR3 backbone conformation of the heavy chain and not the side chain interactions. These results confirm that these monoclonals use germline-encoded amino acids to recognize simple carbohydrate determinants like trisaccharide-H but relies on somatic mutations in the periphery of the combining site to modify affinity for LeY through electrostatic interactions that leads to their optimized binding. These observations bring further attention to the role of mutations in T-cell independent antibodies to distinguish self from non-self carbohydrate antigens.

  18. Crystal Structure of HIV-1 Primary Receptor CD4 i Complex with a Potent Antiviral Antibody

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    Freeman, M.M.; Hong, X.; Seaman, M.S.; Rits-Vollock, S.p Kao, C.Y.; Ho, D.D.; Chen, B.

    2010-06-18

    Ibalizumab is a humanized, anti-CD4 monoclonal antibody. It potently blocks HIV-1 infection and targets an epitope in the second domain of CD4 without interfering with immune functions mediated by interaction of CD4 with major histocompatibility complex (MHC) class II molecules. We report here the crystal structure of ibalizumab Fab fragment in complex with the first two domains (D1-D2) of CD4 at 2.2 {angstrom} resolution. Ibalizumab grips CD4 primarily by the BC-loop (residues 121125) of D2, sitting on the opposite side of gp120 and MHC-II binding sites. No major conformational change in CD4 accompanies binding to ibalizumab. Both monovalent and bivalent forms of ibalizumab effectively block viral infection, suggesting that it does not need to crosslink CD4 to exert antiviral activity. While gp120-induced structural rearrangements in CD4 are probably minimal, CD4 structural rigidity is dispensable for ibalizumab inhibition. These results could guide CD4-based immunogen design and lead to a better understanding of HIV-1 entry.

  19. Crystal structure of HIV-1 primary receptor CD4 in complex with a potent antiviral antibody.

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    Freeman, Michael M; Seaman, Michael S; Rits-Volloch, Sophia; Hong, Xinguo; Kao, Chia-Ying; Ho, David D; Chen, Bing

    2010-12-08

    Ibalizumab is a humanized, anti-CD4 monoclonal antibody. It potently blocks HIV-1 infection and targets an epitope in the second domain of CD4 without interfering with immune functions mediated by interaction of CD4 with major histocompatibility complex (MHC) class II molecules. We report here the crystal structure of ibalizumab Fab fragment in complex with the first two domains (D1-D2) of CD4 at 2.2 Å resolution. Ibalizumab grips CD4 primarily by the BC-loop (residues 121-125) of D2, sitting on the opposite side of gp120 and MHC-II binding sites. No major conformational change in CD4 accompanies binding to ibalizumab. Both monovalent and bivalent forms of ibalizumab effectively block viral infection, suggesting that it does not need to crosslink CD4 to exert antiviral activity. While gp120-induced structural rearrangements in CD4 are probably minimal, CD4 structural rigidity is dispensable for ibalizumab inhibition. These results could guide CD4-based immunogen design and lead to a better understanding of HIV-1 entry.

  20. Independent evolution of Fc- and Fab-mediated HIV-1-specific antiviral antibody activity following acute infection

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    Dugast, Anne-Sophie; Stamatatos, Leonidas; Tonelli, Andrew; Suscovich, Todd J.; Licht, Anna F.; Mikell, Iliyana; Ackerman, Margaret E.; Streeck, Hendrik; Klasse, P.J.; Moore, John P.; Alter, Galit

    2014-01-01

    Fc-related antibody activities, such as antibody-dependent cellular cytotoxicity (ADCC), or more broadly, antibody-mediated cellular viral inhibition (ADCVI), play a role in curbing early SIV viral replication, are enriched in human long-term infected non-progressors, and could potentially contribute to protection from infection. However, little is known about the mechanism by which such humoral immune responses are naturally induced following infection. Here we focused on the early evolution of the functional antibody response, largely driven by the Fc portion of the antibody, in the context of the evolving binding and neutralizing antibody response, which is driven mainly by the antibody binding fragment (Fab). We show that ADCVI/ADCC-inducing responses in humans are rapidly generated following acute HIV-1 infection, peak at approximately 6 months post-infection, but decay rapidly in the setting of persistent immune activation, as Fab-related activities persistently increase. Moreover, the loss of Fc activity occurred in synchrony with a loss of HIV-specific IgG3 responses. Our data strongly suggest that Fc- and Fab-related antibody functions are modulated in a distinct manner following acute HIV infection. Vaccination strategies intended to optimally induce both sets of antiviral antibody activities may, therefore, require a fine-tuning of the inflammatory response. PMID:25043633

  1. Antibody complementarity-determining regions (CDRs can display differential antimicrobial, antiviral and antitumor activities.

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    Luciano Polonelli

    Full Text Available BACKGROUND: Complementarity-determining regions (CDRs are immunoglobulin (Ig hypervariable domains that determine specific antibody (Ab binding. We have shown that synthetic CDR-related peptides and many decapeptides spanning the variable region of a recombinant yeast killer toxin-like antiidiotypic Ab are candidacidal in vitro. An alanine-substituted decapeptide from the variable region of this Ab displayed increased cytotoxicity in vitro and/or therapeutic effects in vivo against various bacteria, fungi, protozoa and viruses. The possibility that isolated CDRs, represented by short synthetic peptides, may display antimicrobial, antiviral and antitumor activities irrespective of Ab specificity for a given antigen is addressed here. METHODOLOGY/PRINCIPAL FINDINGS: CDR-based synthetic peptides of murine and human monoclonal Abs directed to: a a protein epitope of Candida albicans cell wall stress mannoprotein; b a synthetic peptide containing well-characterized B-cell and T-cell epitopes; c a carbohydrate blood group A substance, showed differential inhibitory activities in vitro, ex vivo and/or in vivo against C. albicans, HIV-1 and B16F10-Nex2 melanoma cells, conceivably involving different mechanisms of action. Antitumor activities involved peptide-induced caspase-dependent apoptosis. Engineered peptides, obtained by alanine substitution of Ig CDR sequences, and used as surrogates of natural point mutations, showed further differential increased/unaltered/decreased antimicrobial, antiviral and/or antitumor activities. The inhibitory effects observed were largely independent of the specificity of the native Ab and involved chiefly germline encoded CDR1 and CDR2 of light and heavy chains. CONCLUSIONS/SIGNIFICANCE: The high frequency of bioactive peptides based on CDRs suggests that Ig molecules are sources of an unlimited number of sequences potentially active against infectious agents and tumor cells. The easy production and low cost of small

  2. Antibody Complementarity-Determining Regions (CDRs) Can Display Differential Antimicrobial, Antiviral and Antitumor Activities

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    Polonelli, Luciano; Pontón, José; Elguezabal, Natalia; Moragues, María Dolores; Casoli, Claudio; Pilotti, Elisabetta; Ronzi, Paola; Dobroff, Andrey S.; Rodrigues, Elaine G.; Juliano, Maria A.; Maffei, Domenico Leonardo; Magliani, Walter; Conti, Stefania; Travassos, Luiz R.

    2008-01-01

    Background Complementarity-determining regions (CDRs) are immunoglobulin (Ig) hypervariable domains that determine specific antibody (Ab) binding. We have shown that synthetic CDR-related peptides and many decapeptides spanning the variable region of a recombinant yeast killer toxin-like antiidiotypic Ab are candidacidal in vitro. An alanine-substituted decapeptide from the variable region of this Ab displayed increased cytotoxicity in vitro and/or therapeutic effects in vivo against various bacteria, fungi, protozoa and viruses. The possibility that isolated CDRs, represented by short synthetic peptides, may display antimicrobial, antiviral and antitumor activities irrespective of Ab specificity for a given antigen is addressed here. Methodology/Principal Findings CDR-based synthetic peptides of murine and human monoclonal Abs directed to: a) a protein epitope of Candida albicans cell wall stress mannoprotein; b) a synthetic peptide containing well-characterized B-cell and T-cell epitopes; c) a carbohydrate blood group A substance, showed differential inhibitory activities in vitro, ex vivo and/or in vivo against C. albicans, HIV-1 and B16F10-Nex2 melanoma cells, conceivably involving different mechanisms of action. Antitumor activities involved peptide-induced caspase-dependent apoptosis. Engineered peptides, obtained by alanine substitution of Ig CDR sequences, and used as surrogates of natural point mutations, showed further differential increased/unaltered/decreased antimicrobial, antiviral and/or antitumor activities. The inhibitory effects observed were largely independent of the specificity of the native Ab and involved chiefly germline encoded CDR1 and CDR2 of light and heavy chains. Conclusions/Significance The high frequency of bioactive peptides based on CDRs suggests that Ig molecules are sources of an unlimited number of sequences potentially active against infectious agents and tumor cells. The easy production and low cost of small sized synthetic

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

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    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.

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

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    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...... 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 nAbs against influenza virus. We have developed...

  5. Antiviral antibodies target adenovirus to phagolysosomes and amplify the innate immune response.

    Science.gov (United States)

    Zaiss, Anne K; Vilaysane, Akosua; Cotter, Matthew J; Clark, Sharon A; Meijndert, H Christopher; Colarusso, Pina; Yates, Robin M; Petrilli, Virginie; Tschopp, Jurg; Muruve, Daniel A

    2009-06-01

    Adenovirus is a nonenveloped dsDNA virus that activates intracellular innate immune pathways. In vivo, adenovirus-immunized mice displayed an enhanced innate immune response and diminished virus-mediated gene delivery following challenge with the adenovirus vector AdLacZ suggesting that antiviral Abs modulate viral interactions with innate immune cells. Under naive serum conditions in vitro, adenovirus binding and internalization in macrophages and the subsequent activation of innate immune mechanisms were inefficient. In contrast to the neutralizing effect observed in nonhematopoietic cells, adenovirus infection in the presence of antiviral Abs significantly increased FcR-dependent viral internalization in macrophages. In direct correlation with the increased viral internalization, antiviral Abs amplified the innate immune response to adenovirus as determined by the expression of NF-kappaB-dependent genes, type I IFNs, and caspase-dependent IL-1beta maturation. Immune serum amplified TLR9-independent type I IFN expression and enhanced NLRP3-dependent IL-1beta maturation in response to adenovirus, confirming that antiviral Abs specifically amplify intracellular innate pathways. In the presence of Abs, confocal microscopy demonstrated increased targeting of adenovirus to LAMP1-positive phagolysosomes in macrophages but not epithelial cells. These data show that antiviral Abs subvert natural viral tropism and target the adenovirus to phagolysosomes and the intracellular innate immune system in macrophages. Furthermore, these results illustrate a cross-talk where the adaptive immune system positively regulates the innate immune system and the antiviral state.

  6. Inhibition of Hepatitis C Virus-Like Particle Binding to Target Cells by Antiviral Antibodies in Acute and Chronic Hepatitis C

    Science.gov (United States)

    Steinmann, Daniel; Barth, Heidi; Gissler, Bettina; Schürmann, Peter; Adah, Mohammed I.; Gerlach, J. Tilman; Pape, Gerd R.; Depla, Erik; Jacobs, Dirk; Maertens, Geert; Patel, Arvind H.; Inchauspé, Geneviève; Liang, T. Jake; Blum, Hubert E.; Baumert, Thomas F.

    2004-01-01

    Hepatitis C virus (HCV) is a leading cause of chronic viral hepatitis worldwide. The study of antibody-mediated virus neutralization has been hampered by the lack of an efficient and high-throughput cell culture system for the study of virus neutralization. The HCV structural proteins have been shown to assemble into noninfectious HCV-like particles (HCV-LPs). Similar to serum-derived virions, HCV-LPs bind and enter human hepatocytes and hepatoma cell lines. In this study, we developed an HCV-LP-based model system for a systematic functional analysis of antiviral antibodies from patients with acute or chronic hepatitis C. We demonstrate that cellular HCV-LP binding was specifically inhibited by antiviral antibodies from patients with acute or chronic hepatitis C in a dose-dependent manner. Using a library of homologous overlapping envelope peptides covering the entire HCV envelope, we identified an epitope in the N-terminal E2 region (SQKIQLVNTNGSWHI; amino acid positions 408 to 422) as one target of human antiviral antibodies inhibiting cellular particle binding. Using a large panel of serum samples from patients with acute and chronic hepatitis C, we demonstrated that the presence of antibodies with inhibition of binding activity was not associated with viral clearance. In conclusion, antibody-mediated inhibition of cellular HCV-LP binding represents a convenient system for the functional characterization of human anti-HCV antibodies, allowing the mapping of envelope neutralization epitopes targeted by naturally occurring antiviral antibodies. PMID:15308699

  7. Ethanol and reactive species increase basal sequence heterogeneity of hepatitis C virus and produce variants with reduced susceptibility to antivirals.

    Science.gov (United States)

    Seronello, Scott; Montanez, Jessica; Presleigh, Kristen; Barlow, Miriam; Park, Seung Bum; Choi, Jinah

    2011-01-01

    Hepatitis C virus (HCV) exhibits a high level of genetic variability, and variants with reduced susceptibility to antivirals can occur even before treatment begins. In addition, alcohol decreases efficacy of antiviral therapy and increases sequence heterogeneity of HCV RNA but how ethanol affects HCV sequence is unknown. Ethanol metabolism and HCV infection increase the level of reactive species that can alter cell metabolism, modify signaling, and potentially act as mutagen to the viral RNA. Therefore, we investigated whether ethanol and reactive species affected the basal sequence variability of HCV RNA in hepatocytes. Human hepatoma cells supporting a continuous replication of genotype 1b HCV RNA (Con1, AJ242652) were exposed to ethanol, acetaldehyde, hydrogen peroxide, or L-buthionine-S,R-sulfoximine (BSO) that decreases intracellular glutathione as seen in patients. Then, NS5A region was sequenced and compared with genotype 1b HCV sequences in the database. Ethanol and BSO elevated nucleotide and amino acid substitution rates of HCV RNA by 4-18 folds within 48 hrs which were accompanied by oxidative RNA damage. Iron chelator and glutathione ester decreased both RNA damage and mutation rates. Furthermore, infectious HCV and HCV core gene were sufficient to induce oxidative RNA damage even in the absence of ethanol or BSO. Interestingly, the dn/ds ratio and percentage of sites undergoing positive selection increased with ethanol and BSO, resulting in an increased detection of NS5A variants with reduced susceptibility to interferon alpha, cyclosporine, and ribavirin and others implicated in immune tolerance and modulation of viral replication. Therefore, alcohol is likely to synergize with virus-induced oxidative/nitrosative stress to modulate the basal mutation rate of HCV. Positive selection induced by alcohol and reactive species may contribute to antiviral resistance.

  8. Development of Methods for Carrier-Mediated Targeted Delivery of Antiviral Compounds Using Monoclonal Antibodies

    Science.gov (United States)

    1987-04-01

    Conclusions Ribavirin and the S’-hemlsucclnate derivative of ribavirin were found to have highly significant in vitro antiviral activity against Punto Toro...for later characterization. Cooling equipment with programmable, controlled cooling rates, generally around l°C/minute, is ideal for freezing

  9. Protective antiviral antibody responses in a mouse model of influenza virus infection require TACI

    Science.gov (United States)

    Wolf, Amaya I.; Mozdzanowska, Krystyna; J. Quinn, William; Metzgar, Michele; Williams, Katie L.; Caton, Andrew J.; Meffre, Eric; Bram, Richard J.; Erickson, Loren D.; Allman, David; Cancro, Michael P.; Erikson, Jan

    2011-01-01

    Antiviral Abs, for example those produced in response to influenza virus infection, are critical for virus neutralization and defense against secondary infection. While the half-life of Abs is short, Ab titers can last a lifetime due to a subset of the Ab-secreting cells (ASCs) that is long lived. However, the mechanisms governing ASC longevity are poorly understood. Here, we have identified a critical role for extrinsic cytokine signals in the survival of respiratory tract ASCs in a mouse model of influenza infection. Irradiation of mice at various time points after influenza virus infection markedly diminished numbers of lung ASCs, suggesting that they are short-lived and require extrinsic factors in order to persist. Neutralization of the TNF superfamily cytokines B lymphocyte stimulator (BLyS; also known as BAFF) and a proliferation-inducing ligand (APRIL) reduced numbers of antiviral ASCs in the lungs and bone marrow, whereas ASCs in the spleen and lung-draining lymph node were surprisingly unaffected. Mice deficient in transmembrane activator and calcium-modulator and cyclophilin ligand interactor (TACI), a receptor for BLyS and APRIL, mounted an initial antiviral B cell response similar to that generated in WT mice but failed to sustain protective Ab titers in the airways and serum, leading to increased susceptibility to secondary viral challenge. These studies highlight the importance of TACI signaling for the maintenance of ASCs and protection against influenza virus infection. PMID:21881204

  10. Reactivity of eleven anti-human leucocyte monoclonal antibodies with lymphocytes from several domestic animals

    DEFF Research Database (Denmark)

    Aasted, Bent; Blixenkrone-Møller, Merete; Larsen, Else Bang

    1988-01-01

    Nine commercially available monoclonal antibodies and two monoclonal antibodies from The American Type Culture Collection, raised against various human leucocyte surface antigens, were tested on lymphocytes from cow, sheep, goat, swine, horse, cat, dog, mink, and rabbit as well as man. Four...... antibodies bound to lymphocytes from some of the animals. These were the antibodies against CD8 and CD4 antigen, the antibody to C3b-receptor, and the antibody to the HLA-DR antigen. The CD8 antigen-reactive antibody reacted with lymphocytes from mink, cat, dog, and sheep, while the CD4 antigen...

  11. Cellular impedance measurement as a new tool for poxvirus titration, antibody neutralization testing and evaluation of antiviral substances

    Energy Technology Data Exchange (ETDEWEB)

    Witkowski, Peter T. [Robert Koch-Institut, Zentrum fuer Biologische Sicherheit 1, Nordufer 20, 13353 Berlin (Germany); Charite Universitaetsmedizin, CCM, Institut fuer Virologie, Helmut Ruska Haus, Chariteplatz 1, 10117 Berlin (Germany); Schuenadel, Livia, E-mail: SchuenadelL@rki.de [FU-Berlin, Fachbereich Biologie, Chemie, Pharmazie, Takustrasse 3, 14195 Berlin (Germany); Robert Koch-Institut, Zentrum fuer Biologische Sicherheit 1, Nordufer 20, 13353 Berlin (Germany); Wiethaus, Julia; Bourquain, Daniel R.; Kurth, Andreas; Nitsche, Andreas [Robert Koch-Institut, Zentrum fuer Biologische Sicherheit 1, Nordufer 20, 13353 Berlin (Germany)

    2010-10-08

    Research highlights: {yields} Real-time data acquisition by RT-CES requires low operative effort. {yields} Time to result is reduced by using RT-CES instead of conventional methods. {yields} RT-CES enables quantification of virus titers in unknown samples. {yields} RT-CES is a useful tool for high-throughput characterization of antiviral agents. {yields} An RT-CES-based virus neutralization test was established. -- Abstract: Impedance-based biosensing known as real-time cell electronic sensing (RT-CES) belongs to an emerging technology for analyzing the status of cells in vitro. In the present study protocols were developed for an RT-CES-based system (xCELLigence{sup TM}, Roche Applied Science, ACEA Biosciences Inc.) to supplement conventional techniques in pox virology. First, proliferation of cells susceptible to orthopoxviruses was monitored. For virus titration cells were infected with vaccinia virus and cell status, represented by the dimensionless impedance-based cell index (CI), was monitored. A virus-dose dependent decrease in electrical impedance could be shown. Calculation of calibration curves at a suitable CI covering a dynamic range of 4 log enabled the quantification of virus titers in unknown samples. Similarly, antiviral effects could be determined as shown for anti-poxviral agents ST-246 and Cidofovir. Published values for the in vitro concentration that inhibited virus replication by 50% (IC{sub 50}) could be confirmed while cytotoxicity in effective concentrations was excluded in long-term incubation experiments. Finally, an RT-CES-based virus neutralization test was established. Various poxvirus-specific antibodies were examined for their neutralizing activity and a calculation mode for the neutralizing antibody titer was introduced. In summary, the presented RT-CES-based methods outmatch end-point assays by observing the cell population throughout the entire experiment while workload and time to result are reduced.

  12. Cross-reactive broadly neutralizing antibodies: timing is everything

    OpenAIRE

    Euler, Zelda; Schuitemaker, Hanneke

    2012-01-01

    The recent surge of research into new broadly neutralizing antibodies in HIV-1 infection has recharged the field of HIV-1 vaccinology. In this review we discuss the currently known broadly neutralizing antibodies and focus on factors that may shape these antibodies in natural infection. We further discuss the role of these antibodies in the clinical course of the infection and consider immunological obstacles in inducing broadly neutralizing antibodies with a vaccine.

  13. Cross-reactive broadly neutralizing antibodies: timing is everything.

    Science.gov (United States)

    Euler, Zelda; Schuitemaker, Hanneke

    2012-01-01

    The recent surge of research into new broadly neutralizing antibodies in HIV-1 infection has recharged the field of HIV-1 vaccinology. In this review we discuss the currently known broadly neutralizing antibodies and focus on factors that may shape these antibodies in natural infection. We further discuss the role of these antibodies in the clinical course of the infection and consider immunological obstacles in inducing broadly neutralizing antibodies with a vaccine.

  14. Reactivity of microhemagglutination, fluorescent treponemal antibody absorption, and venereal disease research laboratory tests in primary syphilis.

    Science.gov (United States)

    Dyckman, J D; Storms, S; Huber, T W

    1980-10-01

    Seroreactivity in 130 cases of primary syphilis was 91.5% by fluorescent treponemal antibody absorption test, 82.3% by microhemagglutination (MHA-TP test), and 68.5% by the Venereal Disease Reseach Laboratory (VDRL) test. The MHA TP test generally became reactive earlier than the VDRL test and confirmed all reactive and most weakly reactive VDRL results.

  15. Complement inhibition enables tumor delivery of LCMV glycoprotein pseudotyped viruses in the presence of antiviral antibodies

    Directory of Open Access Journals (Sweden)

    Laura Evgin

    2016-01-01

    Full Text Available The systemic delivery of therapeutic viruses, such as oncolytic viruses or vaccines, is limited by the generation of neutralizing antibodies. While pseudotyping of rhabdoviruses with the lymphocytic choriomeningitis virus glycoprotein has previously allowed for multiple rounds of delivery in mice, this strategy has not translated to other animal models. For the first time, we provide experimental evidence that antibodies generated against the lymphocytic choriomeningitis virus glycoprotein mediate robust complement-dependent viral neutralization via activation of the classical pathway. We show that this phenotype can be capitalized upon to deliver maraba virus pseudotyped with the lymphocytic choriomeningitis virus glycoprotein in a Fischer rat model in the face of neutralizing antibody through the use of complement modulators. This finding changes the understanding of the humoral immune response to arenaviruses, and also describes methodology to deliver viral vectors to their therapeutic sites of action without the interference of neutralizing antibody.

  16. Complement inhibition enables tumor delivery of LCMV glycoprotein pseudotyped viruses in the presence of antiviral antibodies

    Science.gov (United States)

    Evgin, Laura; Ilkow, Carolina S; Bourgeois-Daigneault, Marie-Claude; de Souza, Christiano Tanese; Stubbert, Lawton; Huh, Michael S; Jennings, Victoria A; Marguerie, Monique; Acuna, Sergio A; Keller, Brian A; Lefebvre, Charles; Falls, Theresa; Le Boeuf, Fabrice; Auer, Rebecca A; Lambris, John D; McCart, J Andrea; Stojdl, David F; Bell, John C

    2016-01-01

    The systemic delivery of therapeutic viruses, such as oncolytic viruses or vaccines, is limited by the generation of neutralizing antibodies. While pseudotyping of rhabdoviruses with the lymphocytic choriomeningitis virus glycoprotein has previously allowed for multiple rounds of delivery in mice, this strategy has not translated to other animal models. For the first time, we provide experimental evidence that antibodies generated against the lymphocytic choriomeningitis virus glycoprotein mediate robust complement-dependent viral neutralization via activation of the classical pathway. We show that this phenotype can be capitalized upon to deliver maraba virus pseudotyped with the lymphocytic choriomeningitis virus glycoprotein in a Fischer rat model in the face of neutralizing antibody through the use of complement modulators. This finding changes the understanding of the humoral immune response to arenaviruses, and also describes methodology to deliver viral vectors to their therapeutic sites of action without the interference of neutralizing antibody. PMID:27909702

  17. Preserved antiviral adaptive immunity following polyclonal antibody immunotherapy for severe murine influenza infection.

    Science.gov (United States)

    Stevens, Natalie E; Hatjopolous, Antoinette; Fraser, Cara K; Alsharifi, Mohammed; Diener, Kerrilyn R; Hayball, John D

    2016-07-06

    Passive immunotherapy may have particular benefits for the treatment of severe influenza infection in at-risk populations, however little is known of the impact of passive immunotherapy on the formation of memory responses to the virus. Ideally, passive immunotherapy should attenuate the severity of infection while still allowing the formation of adaptive responses to confer protection from future exposure. In this study, we sought to determine if administration of influenza-specific ovine polyclonal antibodies could inhibit adaptive immune responses in a murine model of lethal influenza infection. Ovine polyclonal antibodies generated against recombinant PR8 (H1N1) hemagglutinin exhibited potent prophylactic capacity and reduced lethality in an established influenza infection, particularly when administered intranasally. Surviving mice were also protected against reinfection and generated normal antibody and cytotoxic T lymphocyte responses to the virus. The longevity of ovine polyclonal antibodies was explored with a half-life of over two weeks following a single antibody administration. These findings support the development of an ovine passive polyclonal antibody therapy for treatment of severe influenza infection which does not affect the formation of subsequent acquired immunity to the virus.

  18. Broadly Reactive Anti-Respiratory Syncytial Virus G Antibodies from Exposed Individuals Effectively Inhibit Infection of Primary Airway Epithelial Cells.

    Science.gov (United States)

    Cortjens, B; Yasuda, E; Yu, X; Wagner, K; Claassen, Y B; Bakker, A Q; van Woensel, J B M; Beaumont, T

    2017-05-15

    Respiratory syncytial virus (RSV) causes severe respiratory disease in young children. Antibodies specific for the RSV prefusion F protein have guided RSV vaccine research, and in human serum, these antibodies contribute to >90% of the neutralization response; however, detailed insight into the composition of the human B cell repertoire against RSV is still largely unknown. In order to study the B cell repertoire of three healthy donors for specificity against RSV, CD27(+) memory B cells were isolated and immortalized using BCL6 and Bcl-xL. Of the circulating memory B cells, 0.35% recognized RSV-A2-infected cells, of which 59% were IgA-expressing cells and 41% were IgG-expressing cells. When we generated monoclonal B cells selected for high binding to RSV-infected cells, 44.5% of IgG-expressing B cells and 56% of IgA-expressing B cells reacted to the F protein, while, unexpectedly, 41.5% of IgG-expressing B cells and 44% of IgA expressing B cells reacted to the G protein. Analysis of the G-specific antibodies revealed that 4 different domains on the G protein were recognized. These epitopes predicted cross-reactivity between RSV strain A (RSV-A) and RSV-B and matched the potency of antibodies to neutralize RSV in HEp-2 cells and in primary epithelial cell cultures. G-specific antibodies were also able to induce antibody-dependent cellular cytotoxicity and antibody-dependent cellular phagocytosis of RSV-A2-infected cells. However, these processes did not seem to depend on a specific epitope. In conclusion, healthy adults harbor a diverse repertoire of RSV glycoprotein-specific antibodies with a broad range of effector functions that likely play an important role in antiviral immunity.IMPORTANCE Human RSV remains the most common cause of severe lower respiratory tract disease in premature babies, young infants, the elderly, and immunocompromised patients and plays an important role in asthma exacerbations. In developing countries, RSV lower respiratory tract disease

  19. Specificity, cross-reactivity, and function of antibodies elicited by Zika virus infection.

    Science.gov (United States)

    Stettler, Karin; Beltramello, Martina; Espinosa, Diego A; Graham, Victoria; Cassotta, Antonino; Bianchi, Siro; Vanzetta, Fabrizia; Minola, Andrea; Jaconi, Stefano; Mele, Federico; Foglierini, Mathilde; Pedotti, Mattia; Simonelli, Luca; Dowall, Stuart; Atkinson, Barry; Percivalle, Elena; Simmons, Cameron P; Varani, Luca; Blum, Johannes; Baldanti, Fausto; Cameroni, Elisabetta; Hewson, Roger; Harris, Eva; Lanzavecchia, Antonio; Sallusto, Federica; Corti, Davide

    2016-08-19

    Zika virus (ZIKV), a mosquito-borne flavivirus with homology to Dengue virus (DENV), has become a public health emergency. By characterizing memory lymphocytes from ZIKV-infected patients, we dissected ZIKV-specific and DENV-cross-reactive immune responses. Antibodies to nonstructural protein 1 (NS1) were largely ZIKV-specific and were used to develop a serological diagnostic tool. In contrast, antibodies against E protein domain I/II (EDI/II) were cross-reactive and, although poorly neutralizing, potently enhanced ZIKV and DENV infection in vitro and lethally enhanced DENV disease in mice. Memory T cells against NS1 or E proteins were poorly cross-reactive, even in donors preexposed to DENV. The most potent neutralizing antibodies were ZIKV-specific and targeted EDIII or quaternary epitopes on infectious virus. An EDIII-specific antibody protected mice from lethal ZIKV infection, illustrating the potential for antibody-based therapy.

  20. Contribution of Peptide Backbone to Anti-Citrullinated Peptide Antibody Reactivity.

    Directory of Open Access Journals (Sweden)

    Nicole Hartwig Trier

    Full Text Available Rheumatoid arthritis (RA is one of the most common autoimmune diseases, affecting approximately 1-2% of the world population. One of the characteristic features of RA is the presence of autoantibodies. Especially the highly specific anti-citrullinated peptide antibodies (ACPAs, which have been found in up to 70% of RA patients' sera, have received much attention. Several citrullinated proteins are associated with RA, suggesting that ACPAs may react with different sequence patterns, separating them from traditional antibodies, whose reactivity usually is specific towards a single target. As ACPAs have been suggested to be involved in the development of RA, knowledge about these antibodies may be crucial. In this study, we examined the influence of peptide backbone for ACPA reactivity in immunoassays. The antibodies were found to be reactive with a central Cit-Gly motif being essential for ACPA reactivity and to be cross-reactive between the selected citrullinated peptides. The remaining amino acids within the citrullinated peptides were found to be of less importance for antibody reactivity. Moreover, these findings indicated that the Cit-Gly motif in combination with peptide backbone is essential for antibody reactivity. Based on these findings it was speculated that any amino acid sequence, which brings the peptide into a properly folded structure for antibody recognition is sufficient for antibody reactivity. These findings are in accordance with the current hypothesis that structural homology rather than sequence homology are favored between citrullinated epitopes. These findings are important in relation to clarifying the etiology of RA and to determine the nature of ACPAs, e.g., why some Cit-Gly-containing sequences are not targeted by ACPAs.

  1. Transfusion-induced, Fc gamma-receptor-blocking antibodies: spectrum of cellular reactivity.

    Science.gov (United States)

    Forwell, M A; Peel, M G; Froebel, K S; Belch, J J; MacSween, R N; Sandilands, G P

    1986-06-01

    In this study we have shown that transfusion-induced Fc gamma R-blocking antibodies have the capacity to react with various cell types which are known to possess this receptor i.e., lymphocytes (T and B cells), polymorphs and platelets. In contrast we were unable to demonstrate any reactivity with K (or NK) lymphocytes or with monocytes. The spectrum of cellular reactivity exhibited by these antibodies suggests that their effect on the immune system may be complex.

  2. Molecular Evolution of Antibody Cross-Reactivity for Two Subtypes of Type a Botulinum Neurotoxin

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Rodriguez, C.; Levy, R.; Arndt, J.W.; Forsyth, C.M.; Razai, A.; Lou, J.; Geren, I.; Stevens, R.C.; Marks, J.D.; /UC, San Francisco /Scripps Res. Inst.

    2007-07-09

    Broadening antibody specificity without compromising affinity should facilitate detection and neutralization of toxin and viral subtypes. We used yeast display and a co-selection strategy to increase cross-reactivity of a single chain (sc) Fv antibody to botulinum neurotoxin type A (BoNT/A). Starting with a scFv that binds the BoNT/A1 subtype with high affinity (136 pM) and the BoNT/A2 subtype with low affinity (109 nM), we increased its affinity for BoNT/A2 1,250-fold, to 87 pM, while maintaining high-affinity binding to BoNT/A1 (115 pM). To find the molecular basis for improved cross-reactivity, we determined the X-ray co-crystal structures of wild-type and cross-reactive antibodies complexed to BoNT/A1 at resolutions up to 2.6 A, and measured the thermodynamic contribution of BoNT/A1 and A2 amino acids to wild-type and cross-reactive antibody binding. The results show how an antibody can be engineered to bind two different antigens despite structural differences in the antigen-antibody interface and may provide a general strategy for tuning antibody specificity and cross-reactivity.

  3. Evaluation of cross-reactive antibody response to HVR1 in chronic hepatitis C

    Science.gov (United States)

    Xiu, Bing-Shui; Feng, Xiao-Yan; He, Jing; Wang, Guo-Hua; Zhang, Xiang-Ying; Zhang, He-Qiu; Song, Xiao-Guo; Chen, Kun; Ling, Shi-Gan; Zhu, Cui-Xia; Wei, Lai; Rao, Hui-Ying

    2010-01-01

    AIM: To evaluate the presence and cross-reactive antibodies against hypervariable region 1 (HVR1) in hepatitis C virus (HCV) infected patients and its relationship with the progression of the disease. METHODS: Sixteen representative HVR1 proteins selected from a unique set of 1600 natural sequences were used to semiquantitate the cross-reactivity of HVR1 antibodies in the sera of HCV patients. Fifty-five chronic HCV patients including 23 with asymptomatic mild hepatitis, 18 with chronic hepatitis and 16 with liver cirrhosis patients were studied. RESULTS: The degree of the cross-reactivity of anti-HVR1 antibodies in 23 patients with mild asymptomatic hepatitis was 3.09 ± 2.68, which was significantly lower than in those with chronic hepatitis (5.44 ± 3.93, P < 0.05) and liver cirrhosis (7.44 ± 3.90, P < 0.01). No correlation was observed between the broadness of the cross-reactivity anti-HVR1 antibodies and patient’s age, infection time, serum alanine aminotransferase activity, or serum HCV-RNA concentration. It was the breath of cross-reactivity rather than the presence of anti-HVR1 antibody in HCV sera that was associated with the progression of liver disease. CONCLUSION: The broadly cross-reactive HVR1 antibodies generated in natural HCV patients can not neutralize the virus, which results in persistent infection in patients with chronic hepatitis. PMID:20845515

  4. A Spectrum of Monoclonal Antibodies Reactive with Human Mammary Tumor Cells

    Science.gov (United States)

    Colcher, D.; Horan Hand, P.; Nuti, M.; Schlom, J.

    1981-05-01

    Splenic lymphocytes of mice, immunized with membrane-enriched fractions of metastatic human mammary carcinoma tissues, were fused with the NS-1 non-immunoglobulin-secreting murine myeloma cell line. This resulted in the generation of hybridoma cultures secreting immunoglobulins reactive in solid-phase radioimmunoassays with extracts of metastatic mammary carcinoma cells from involved livers, but not with extracts of apparently normal human liver. As a result of further screening of immunoglobulin reactivities and double cloning of cultures, 11 monoclonal antibodies were chosen that demonstrated reactivities with human mammary tumor cells and not with apparently normal human tissues. These monoclonal antibodies could be placed into at least five major groups on the basis of their differential binding to the surface of various live human mammary tumor cells in culture, to extracts of mammary tumor tissues, or to tissue sections of mammary tumor cells studied by the immunoperoxidase technique. Whereas a spectrum of reactivities to mammary tumors was observed with the 11 monoclonal antibodies, no reactivity was observed to apparently normal cells of the following human tissues: breast, lymph node, lung, skin, testis, kidney, thymus, bone marrow, spleen, uterus, thyroid, intestine, liver, bladder, tonsils, stomach, prostate, and salivary gland. Several of the antibodies also demonstrated a ``pancarcinoma'' reactivity, showing binding to selected non-breast carcinomas. None of the monoclonal antibodies showed binding to purified ferritin or carcinoembryonic antigen. Monoclonal antibodies of all five major groups, however, demonstrated binding to human metastatic mammary carcinoma cells both in axillary lymph nodes and at distal sites.

  5. Intracellular reprogramming of expression, glycosylation, and function of a plant-derived antiviral therapeutic monoclonal antibody.

    Directory of Open Access Journals (Sweden)

    Jeong-Hwan Lee

    Full Text Available Plant genetic engineering, which has led to the production of plant-derived monoclonal antibodies (mAb(Ps, provides a safe and economically effective alternative to conventional antibody expression methods. In this study, the expression levels and biological properties of the anti-rabies virus mAb(P SO57 with or without an endoplasmic reticulum (ER-retention peptide signal (Lys-Asp-Glu-Leu; KDEL in transgenic tobacco plants (Nicotiana tabacum were analyzed. The expression levels of mAb(P SO57 with KDEL (mAb(PK were significantly higher than those of mAb(P SO57 without KDEL (mAb(P regardless of the transcription level. The Fc domains of both purified mAb(P and mAb(PK and hybridoma-derived mAb (mAb(H had similar levels of binding activity to the FcγRI receptor (CD64. The mAb(PK had glycan profiles of both oligomannose (OM type (91.7% and Golgi type (8.3%, whereas the mAb(P had mainly Golgi type glycans (96.8% similar to those seen with mAb(H. Confocal analysis showed that the mAb(PK was co-localized to ER-tracker signal and cellular areas surrounding the nucleus indicating accumulation of the mAb(P with KDEL in the ER. Both mAb(P and mAb(PK disappeared with similar trends to mAb(H in BALB/c mice. In addition, mAb(PK was as effective as mAb(H at neutralizing the activity of the rabies virus CVS-11. These results suggest that the ER localization of the recombinant mAb(P by KDEL reprograms OM glycosylation and enhances the production of the functional antivirus therapeutic antibody in the plant.

  6. Lack of antiviral antibody response in koalas infected with koala retroviruses (KoRV).

    Science.gov (United States)

    Fiebig, Uwe; Keller, Martina; Möller, Annekatrin; Timms, Peter; Denner, Joachim

    2015-02-16

    Many wild koalas are infected with the koala retrovirus, KoRV, some of which suffer from lymphoma and chlamydial disease. Three subgroups, KoRV-A, KoRV-B and KoRV-J, have so far been described. It is well known that other closely related gammaretroviruses can induce tumours and severe immunodeficiencies in their respective hosts and a possible role for KoRV infection in lymphoma and chlamydial disease in koalas has been suggested. In many wild koalas, KoRV-A has become endogenised, i.e., it is integrated in the germ-line and is passed on with normal cellular genes. In this study, sera from koalas in European zoos and from wild animals in Australia were screened for antibodies against KoRV-A. These naturally infected animals all carry endogenous KoRV-A and two zoo animals are also infected with KoRV-B. The antibody response is generally an important diagnostic tool for detecting retrovirus infections. However, when Western blot analyses were performed using purified virus or recombinant proteins corresponding to KoRV-A, none of the koalas tested positive for specific antibodies, suggesting a state of tolerance. These results have implications for koala vaccination, as they suggest that therapeutic immunisation of animals carrying and expressing endogenous KoRV-A will not be successful. However, it remains unclear whether these animals can be immunised against KoRV-B and immunisation of uninfected koalas could still be worthwhile. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Crystal structure of HIV-1 primary receptor CD4 in complex with a potent antiviral antibody

    OpenAIRE

    Freeman, Michael M.; Seaman, Michael S; Rits-Volloch, Sophia; Hong, Xinguo; Kao, Chia-Ying; Ho, David D.; Chen, Bing

    2010-01-01

    Ibalizumab is a humanized, anti-CD4 monoclonal antibody. It potently blocks HIV-1 infection and targets an epitope in the second domain of CD4 without interfering with immune functions mediated by interaction of CD4 with major histocompatibility complex (MHC) class II molecules. We report here the crystal structure of ibalizumab Fab fragment in complex with the first two domains (D1-D2) of CD4 at 2.2 Å resolution. Ibalizumab grips CD4 primarily by the BC-loop (residues 121-125) of D2, sitting...

  8. Maturation Pathways of Cross-Reactive HIV-1 Neutralizing Antibodies

    Directory of Open Access Journals (Sweden)

    Dimiter S. Dimitrov

    2009-11-01

    Full Text Available Several human monoclonal antibodies (hmAbs and antibody fragments, including the best characterized in terms of structure-function b12 and Fab X5, exhibit relatively potent and broad HIV-1 neutralizing activity. However, the elicitation of b12 or b12-like antibodies in vivo by vaccine immunogens based on the HIV-1 envelope glycoprotein (Env has not been successful. B12 is highly divergent from the closest corresponding germline antibody while X5 is less divergent. We have hypothesized that the relatively high degree of specific somatic hypermutations may preclude binding of the HIV-1 envelope glycoprotein (Env to closest germline antibodies, and that identifying antibodies that are intermediates in the pathways to maturation could help design novel vaccine immunogens to guide the immune system for their enhanced elicitation. In support of this hypothesis we have previously found that a germline-like b12 (monovalent and bivalent scFv as an Fc fusion protein or IgG lacks measurable binding to an Env as measured by ELISA with a sensitivity in the μM range [1]; here we present evidence confirming and expanding these findings for a panel of Envs. In contrast, a germline-like scFv X5 bound Env with high (nM affinity. To begin to explore the maturation pathways of these antibodies we identified several possible b12 intermediate antibodies and tested their neutralizing activity. These intermediate antibodies neutralized only some HIV-1 isolates and with relatively weak potency. In contrast, germline-like scFv X5 neutralized a subset of the tested HIV-1 isolates with comparable efficiencies to that of the mature X5. These results could help explain the relatively high immunogenicity of the coreceptor binding site on gp120 and the abundance of CD4-induced (CD4i antibodies in HIV-1-infected patients (X5 is a CD4i antibody as well as the maturation pathway of X5. They also can help identify antigens that can bind specifically to b12 germline and

  9. VIRAL- REACTIVATED PNEUMONIA DURING MECHANICAL VENTILATION: Is there need for antiviral treatment?

    Directory of Open Access Journals (Sweden)

    Alejandra eLópez-Giraldo

    2011-11-01

    Full Text Available Respiratory viruses are not a common cause of VAP. Herpesviridae (HSV and CMV are detected frequently in the lower respiratory tract of ventilated patients. HSV is detected between days 7 and 14 of IMV; presence of the virus does not necessarily imply pathogenicity, but the association with adverse clinical outcomes supports the hypothesis of a pathogenic role in a variable percentage of patients. Bronchopneumonitis associated with HSV should be considered in patients with prolonged IMV, reactivation with herpetic mucocutaneous lesions and those belonging to a risk population with burn injuries or acute lung injury.Reactivation of CMV is common in critically ill patients and usually occurs between days 14 and 21 in patients with defined risk factors. The potential pathogenic role of CMV seems clear in patients with acute lung injury and persistent respiratory failure in whom there is no isolation of bacterial agent as a cause of VAP. The best diagnostic test is not defined although lung biopsies should be considered in addition to the usual methods before starting specific treatment.The role of mimivirus is uncertain and is yet to be defined, but the serologic evidence of this new virus in the context of VAP appears to be associated with adverse clinical outcomes.

  10. Crystal structure of the Hendra virus attachment G glycoprotein bound to a potent cross-reactive neutralizing human monoclonal antibody.

    Directory of Open Access Journals (Sweden)

    Kai Xu

    Full Text Available The henipaviruses, represented by Hendra (HeV and Nipah (NiV viruses are highly pathogenic zoonotic paramyxoviruses with uniquely broad host tropisms responsible for repeated outbreaks in Australia, Southeast Asia, India and Bangladesh. The high morbidity and mortality rates associated with infection and lack of licensed antiviral therapies make the henipaviruses a potential biological threat to humans and livestock. Henipavirus entry is initiated by the attachment of the G envelope glycoprotein to host cell membrane receptors. Previously, henipavirus-neutralizing human monoclonal antibodies (hmAb have been isolated using the HeV-G glycoprotein and a human naïve antibody library. One cross-reactive and receptor-blocking hmAb (m102.4 was recently demonstrated to be an effective post-exposure therapy in two animal models of NiV and HeV infection, has been used in several people on a compassionate use basis, and is currently in development for use in humans. Here, we report the crystal structure of the complex of HeV-G with m102.3, an m102.4 derivative, and describe NiV and HeV escape mutants. This structure provides detailed insight into the mechanism of HeV and NiV neutralization by m102.4, and serves as a blueprint for further optimization of m102.4 as a therapeutic agent and for the development of entry inhibitors and vaccines.

  11. Crystal structure of the Hendra virus attachment G glycoprotein bound to a potent cross-reactive neutralizing human monoclonal antibody.

    Science.gov (United States)

    Xu, Kai; Rockx, Barry; Xie, Yihu; DeBuysscher, Blair L; Fusco, Deborah L; Zhu, Zhongyu; Chan, Yee-Peng; Xu, Yan; Luu, Truong; Cer, Regina Z; Feldmann, Heinz; Mokashi, Vishwesh; Dimitrov, Dimiter S; Bishop-Lilly, Kimberly A; Broder, Christopher C; Nikolov, Dimitar B

    2013-01-01

    The henipaviruses, represented by Hendra (HeV) and Nipah (NiV) viruses are highly pathogenic zoonotic paramyxoviruses with uniquely broad host tropisms responsible for repeated outbreaks in Australia, Southeast Asia, India and Bangladesh. The high morbidity and mortality rates associated with infection and lack of licensed antiviral therapies make the henipaviruses a potential biological threat to humans and livestock. Henipavirus entry is initiated by the attachment of the G envelope glycoprotein to host cell membrane receptors. Previously, henipavirus-neutralizing human monoclonal antibodies (hmAb) have been isolated using the HeV-G glycoprotein and a human naïve antibody library. One cross-reactive and receptor-blocking hmAb (m102.4) was recently demonstrated to be an effective post-exposure therapy in two animal models of NiV and HeV infection, has been used in several people on a compassionate use basis, and is currently in development for use in humans. Here, we report the crystal structure of the complex of HeV-G with m102.3, an m102.4 derivative, and describe NiV and HeV escape mutants. This structure provides detailed insight into the mechanism of HeV and NiV neutralization by m102.4, and serves as a blueprint for further optimization of m102.4 as a therapeutic agent and for the development of entry inhibitors and vaccines.

  12. Functional and immunochemical cross-reactivity of V2-specific monoclonal antibodies from HIV-1-infected individuals

    Energy Technology Data Exchange (ETDEWEB)

    Gorny, Miroslaw K.; Pan, Ruimin; Williams, Constance; Wang, Xiao-Hong; Volsky, Barbara; O; Neal, Timothy; Spurrier, Brett; Sampson, Jared M.; Li, Liuzhe; Seaman, Michael S.; Kong, Xiang-Peng; Zolla-Pazner, Susan (Harvard-Med); (VA); (NYUSM)

    2012-05-18

    The recent analysis of the first successful RV144 vaccine trial revealed that a high titer of plasma anti-V2 antibodies (Abs) correlated with a decreased risk of HIV-1 infection in vaccine recipients. To understand the mechanism of immune correlates, we studied seven anti-V2 monoclonal Abs (mAbs) developed from HIV-1 infected individuals. The V2 mAbs target conserved epitopes, including the binding site for {alpha}4{beta}7 integrin, and are broadly cross-reactive with various gp120 proteins. Preferential usage of the VH1-69 gene by V2 mAbs may depend on selection by the same antigenic structure. Six of seven V2 mAbs weakly neutralized four to eight of the 41 pseudoviruses tested and resistance to neutralization was correlated with longer V2 domains. The data suggest the presence of shared, conserved structural elements in the V2 loop, and these can be used in the design of vaccine immunogens inducing broadly reactive Abs with anti-viral activities.

  13. Neuroticism, cortisol reactivity, and antibody response to vaccination

    OpenAIRE

    Anna C. Phillips; Carroll, Douglas; Burns, Victoria E.; Drayson, Mark

    2005-01-01

    This study examined whether neuroticism was related to the antibody response to influenza vaccination and whether the relationship was mediated by cortisol reactions to an acute laboratory mental stress. Antibody status was assessed at baseline and to a trivalent influenza vaccination in 57 students at five-weeks and five-month follow-up. Neuroticism was also measured at baseline. Cortisol was measured at rest and in response to a pressurised mental arithmetic task. At both follow-ups, hi...

  14. Limited cross-reactivity of mouse monoclonal antibodies against Dengue virus capsid protein among four serotypes

    Directory of Open Access Journals (Sweden)

    Noda M

    2012-11-01

    Full Text Available Megumi Noda,1 Promsin Masrinoul,1 Chaweewan Punkum,1 Chonlatip Pipattanaboon,2,3 Pongrama Ramasoota,2,4 Chayanee Setthapramote,2,3 Tadahiro Sasaki,6 Mikiko Sasayama,1 Akifumi Yamashita,1,5 Takeshi Kurosu,6 Kazuyoshi Ikuta,6 Tamaki Okabayashi11Mahidol-Osaka Center for Infectious Diseases, 2Center of Excellence for Antibody Research, 3Department of Microbiology and Immunology, 4Department of Social and Environmental Medicine, Faculty of Tropical Medicine, Mahidol University, Ratchathewi, Bangkok, Thailand; 5Graduate School of Life Science, Tohoku University, Sendai, Miyagi, 6Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, JapanBackground: Dengue illness is one of the important mosquito-borne viral diseases in tropical and subtropical regions. Four serotypes of dengue virus (DENV-1, DENV-2, DENV-3, and DENV-4 are classified in the Flavivirus genus of the family Flaviviridae. We prepared monoclonal antibodies against DENV capsid protein from mice immunized with DENV-2 and determined the cross-reactivity with each serotype of DENV and Japanese encephalitis virus.Methods and results: To clarify the relationship between the cross-reactivity of monoclonal antibodies and the diversity of these viruses, we examined the situations of flaviviruses by analyses of phylogenetic trees. Among a total of 60 prepared monoclonal antibodies specific for DENV, five monoclonal antibodies stained the nuclei of infected cells and were found to be specific to the capsid protein. Three were specific to DENV-2, while the other two were cross-reactive with DENV-2 and DENV-4. No monoclonal antibodies were cross-reactive with all four serotypes. Phylogenetic analysis of DENV amino acid sequences of the capsid protein revealed that DENV-2 and DENV-4 were clustered in the same branch, while DENV-1 and DENV-3 were clustered in the other branch. However, these classifications of the capsid protein were different from those of the

  15. Vaccine-induced cross-genotype reactive neutralizing antibodies against hepatitis C virus

    DEFF Research Database (Denmark)

    Meunier, Jean-Christophe; Gottwein, Judith M; Houghton, Michael

    2011-01-01

    We detected cross-reactive neutralizing antibodies (NtAb) against hepatitis C virus (HCV) in chimpanzees vaccinated with HCV-1 (genotype 1a) recombinant E1/E2 envelope glycoproteins. Five vaccinated chimpanzees, protected following HCV-1 challenge, were initially studied using the heterologous H77......a, with limited reactivity against 2a and 3a. Our study provides encouragement for the development of a recombinant envelope-based vaccine against hepatitis C....

  16. Cross-reactivity between immunoglobulin G antibodies of whales and dolphins correlates with evolutionary distance.

    Science.gov (United States)

    Nollens, Hendrik H; Ruiz, Carolina; Walsh, Michael T; Gulland, Frances M D; Bossart, Gregory; Jensen, Eric D; McBain, James F; Wellehan, James F X

    2008-10-01

    Growing morphological and molecular evidence indicates that the porpoises, dolphins, and whales evolved within the even-toed ungulates, formerly known as Artiodactyla. These animals are now grouped in the Cetartiodactyla. We evaluated the antigenic similarity of the immunoglobulin G (IgG) molecules of 15 cetacean species and the domestic cow. The similarity was scored using three distinct antibodies raised against bottlenose dolphin (Tursiops truncatus) IgG in a Western blot, an indirect enzyme-linked immunosorbent assay (ELISA), and a competitive ELISA format. A score was generated for the genetic distance between each species and T. truncatus using the cytochrome b sequence. Each antibody displayed a distinct pattern of reactivity with the IgG antibodies of the various species. The monoclonal antibody (MAb) specific for the gamma heavy chain of T. truncatus was reactive with all monodontids, delphinids, and phocoenids. The light-chain-specific MAb reacted with IgG of delphinoid and phocoenid species and one of the two mysticete species tested. The polyclonal antibody was broadly cross-reactive across all cetaceans and the domestic cow. Using the MAb specific for the gamma heavy chain, the degree of IgG cross-reactivity ranged from less than 17% for the mysticetes to 106% for killer whale Orcinus orca. The IgG in beaked whale and baleen whale sera was significantly less cross-reactive with bottlenose dolphin IgG than sera from other toothed whales. A strong negative correlation was demonstrated between antigenic cross-reactivity of IgG molecules and the genetic distance of their hosts. The data generated will be useful for the development of clinical serodiagnostics in diverse cetacean species.

  17. Cross-reactivity of secondary antibodies against African rodents and application for sero-surveillance.

    Science.gov (United States)

    Nakamura, Ichiro; Hang'ombe, Bernard Mudenda; Sawa, Hirofumi; Kobayashi, Shintaro; Orba, Yasuko; Ishii, Akihiro; Thomas, Yuka; Isozumi, Rie; Yoshimatsu, Kumiko; Mweene, Aaron S; Takada, Ayato; Sugimoto, Chihiro; Arikawa, Jiro

    2013-01-01

    A total of 466 rodents were captured in the Republic of Zambia from 2006 to 2010. Based on morphological observations and phylogenetic analyses of mitochondrial gene sequences, rodents were divided into 10 groups consisting of 39 Rattus rodents, 263 multimammate rats, 18 other Murinae rodents, 95 gerbils, 11 pouched mice, 1 giant-pouched rat, 38 fat mice and 1 dormouse. Rodent antibodies except that from Rattus were examined for their cross-reactivity to commercially available antibody detection reagents. Anti-mouse immunoglobulin G (IgG) was most cross-reactive to heterologous antibodies including multimammate rat, gerbil, pouched mouse and fat mouse. Thus, anti-mouse IgG would be a useful detection tool in serological examination of the Zambian rodent population. Preliminary sero-surveillance for plague, leptospirosis and hantavirus infection was performed by ELISA.

  18. Cross-reactivity of human and bovine antibodies in striped dolphin paraffin wax-embedded tissues.

    Science.gov (United States)

    Jaber, J R; Fernández, A; Herráez, P; Espinosa de los Monteros, A; Ramírez, G A; García, P M; Fernández, T; Arbelo, M; Pérez, J

    2003-11-15

    This study evaluates the cross-reactivity of seven anti-human and one anti-bovine antibodies in formalin-fixed, paraffin-embedded tissue samples of liver and mesenteric lymph nodes of 13 striped dolphins (Stenella coeruleoalba). Four antibodies (CD3, IgG, lysozyme and S100 protein) reacted with striped dolphin lymph nodes in a similar pattern to that observed in the species of origin. The anti-human MHC class II mAb reacted strongly with macrophages and dendritic-like cells of striped dolphins, whereas a small number of lymphocytes were labelled with this antibody. These antibodies were used to study the immunophenotype of the inflammatory infiltrated in non-specific chronic reactive hepatitis (eight cases) and chronic parasite cholangitis (two cases) and normal liver (three cases) of striped dolphins. Non-specific chronic reactive hepatitis was composed of inflammatory infiltration of CD3+ T lymphocytes and IgG+ plasma cells in portal spaces and hepatic sinusoids. Lymphonodular aggregates observed in chronic parasitic cholangitis showed a cellular distribution similar to that found in lymph node cortex, including the presence of S100+ and MHC class II+ dendritic-like cells in lymphoid follicles and interfollicular areas. This result suggests that those inflammatory infiltrates are highly organised to enhance antigen presentation to B and T cells.

  19. Antibodies with specificity for native and denatured forms of ovalbumin differ in reactivity between enzyme-linked immunosorbent assays

    DEFF Research Database (Denmark)

    Holm, B.E.; Bergmann, A.C.; Hansen, Paul Robert

    2015-01-01

    In this study, polyclonal and monoclonal antibodies to native and denatured chicken ovalbumin (OVA) were produced to compare their dependency on continuous and three-dimensional epitopes. These antibodies were characterized with respect to reactivity to native and denatured OVA by enzyme...... to native OVA reacted strongly with native and denatured OVA in both assays, but did not react with the overlapping peptides. Polyclonal antibodies to denatured OVA reacted strongly with both OVA forms and with several of the overlapping peptides. Monoclonal antibodies to native OVA reacted preferentially...... with three-dimensional epitopes on native OVA and not with denatured OVA. Monoclonal antibodies to denatured OVA showed reactivity to both OVA forms. Two of these monoclonal antibodies, HYB 94-06 and 94-07, showed reactivity to overlapping peptides and their epitopes were identified as flexible structures...

  20. Signature biochemical properties of broadly cross-reactive HIV-1 neutralizing antibodies in human plasma.

    Science.gov (United States)

    Sajadi, Mohammad M; Lewis, George K; Seaman, Michael S; Guan, Yongjun; Redfield, Robert R; DeVico, Anthony L

    2012-05-01

    The common properties of broadly cross-reactive HIV-1 neutralization antibodies found in certain HIV-1-infected individuals holds significant value for understanding natural and vaccine-mediated anti-HIV immunity. Recent efforts have addressed this question by deriving neutralizing monoclonal anti-envelope antibodies from memory B cell pools of selected subjects. However, it has been more difficult to identify whether broadly neutralizing antibodies circulating in plasma possess shared characteristics among individuals. To address this question, we used affinity chromatography and isoelectric focusing to fractionate plasma immunoglobulin from 10 HIV-1-infected subjects (5 subjects with broad HIV-1 neutralizing activity and 5 controls). We find that plasma neutralizing activity typically partitions into at least two subsets of antibodies. Antibodies with restricted neutralization breadth have relatively neutral isoelectric points and preferentially bind to envelope monomers and trimers versus core antigens from which variable loops and other domains have been deleted. In comparison, broadly neutralizing antibodies account for a minor fraction of the total anti-envelope response. They are consistently distinguished by more basic isoelectric points and specificity for epitopes shared by monomeric gp120, gp120 core, or CD4-induced structures. Such biochemical properties might be exploited to reliably predict or produce broad anti-HIV immunity.

  1. Trypanosoma cruzi: serum antibody reactivity to the parasite antigens in susceptible and resistant mice

    OpenAIRE

    1990-01-01

    The specific antibody responses were compared among susceptible (A/Sn), moderately susceptible (Balb/c) and resistant (C57 BL/lOJ) mice infected with Trypanosoma cruzi (Y strain). Sera obtained during the second week of infection recognized a surface trypomastigote antigen of apparent Mr 80 kDa while displaying complex reactivity to surface epimastigote antigens. Complex trypomastigote antigens recognition was detected around the middle of the third week of infection. No major differences wer...

  2. Antibodies reactive with Bartonella henselae and Ehrlichia canis in dogs from the communal lands of Zimbabwe

    Directory of Open Access Journals (Sweden)

    P.J. Kelly

    2004-06-01

    Full Text Available The prevalences of antibodies against Bartonella henselae and Ehrlichia canis were determined in sera from 228 dogs in 5 communal lands of Zimbabwe, areas where traditional subsistence agro-pastoralism is practised. The sera were collected from apparently healthy dogs during routine rabies vaccination programmes and tested with indirect fluorescent antibody assays using B. henselae (Houston-I and E. canis (Oklahoma as antigens. We found reactive antibodies (>1:80 against B. henselae in 14 % of the dogs tested. Seropositive animals were found in Bikita (41 %; 17/42, Omay (13 %; 6/48, Chinamora (5 %; 2/38 and Matusadona (15 %; 7/48. No seropositive dogs were found in Chiredzi (0 %; 0/52. Antibodies reactive with E. canis (>1:80 were found in 34%of the dogs tested, from Bikita (88 %; 37/42, Chiredzi (31 %; 16/52, Omay (17 %; 8/48, Chinamora (26 %; 10/38 and Matusadona (15 %; 7/48. Our survey shows dogs in the communal lands of Zimbabwe are frequently exposed to E. canis and B. henselae or closely related species. Further studies are indicated to determine the pathogenicity of the organisms infecting these dogs and their clinical significance.

  3. Caspr2-reactive antibody cloned from a mother of an ASD child mediates an ASD-like phenotype in mice.

    Science.gov (United States)

    Brimberg, L; Mader, S; Jeganathan, V; Berlin, R; Coleman, T R; Gregersen, P K; Huerta, P T; Volpe, B T; Diamond, B

    2016-12-01

    Autism spectrum disorder (ASD) occurs in 1 in 68 births, preferentially affecting males. It encompasses a group of neurodevelopmental abnormalities characterized by impaired social interaction and communication, stereotypic behaviors and motor dysfunction. Although recent advances implicate maternal brain-reactive antibodies in a causative role in ASD, a definitive assessment of their pathogenic potential requires cloning of such antibodies. Here, we describe the isolation and characterization of monoclonal brain-reactive antibodies from blood of women with brain-reactive serology and a child with ASD. We further demonstrate that male but not female mice exposed in utero to the C6 monoclonal antibody, binding to contactin-associated protein-like 2 (Caspr2), display abnormal cortical development, decreased dendritic complexity of excitatory neurons and reduced numbers of inhibitory neurons in the hippocampus, as well as impairments in sociability, flexible learning and repetitive behavior. Anti-Caspr2 antibodies are frequent in women with brain-reactive serology and a child with ASD. Together these studies provide a methodology for obtaining monclonal brain-reactive antibodies from blood B cells, demonstrate that ASD can result from in utero exposure to maternal brain-reactive antibodies of single specificity and point toward the exciting possibility of prognostic and protective strategies.

  4. Antigenic Cross-Reactivity Anti-Birtoxin Antibody against Androctonus crassicauda Venom

    Directory of Open Access Journals (Sweden)

    SuhandanAdigüzel Van-Zoelen

    2015-10-01

    Full Text Available Background: Antivenom is still widely used in the treatment of envenomation as there are no vaccines or other effective agents available against animal venoms. Recently, neurotoxins named birtoxin family have been described from Parabuthus transvaalicus and Androctonus crassicauda. The aim of the present study was to test the antibirtoxinantibodies for their ability to neutralize the lethal effects of A. crassicauda scorpion venom.Methods: SDS-PAGE and Western blotting used the presence of components from A. crassicauda and P.transvaalicus scorpion venoms and to determine the degree of cross-reactivity. The Minimum Lethal Dose (MLD of venom was assessed by subcutaneously (sc injections in mice.Results: The MLD of the A. crassicauda venom was 35 μg/ 20g mouse by sc injection route. Western blotting showed the presence of components from A. crassicauda and P. transvaalicus scorpion venoms strongly cross react with the A. crassicauda antivenom. However, Western blotting of the A. crassicauda scorpion venom using the Refik Saydam Public Health Agency (RSPHA generated antibody showed that not all the venom components cross reacted with the anti-birtoxin antibody. The antibodies only cross reacted with components falling under the 19 kDa protein size of A. crassicauda venom.Conclusion: The bioassays and Western blotting of A. crassicauda venom with the anti-birtoxin antibodies produced against a synthetic peptide showed that these antibodies cross reacted but did not neutralize the venom of A. crassicauda.

  5. Structural basis for Marburg virus neutralization by a cross-reactive human antibody.

    Science.gov (United States)

    Hashiguchi, Takao; Fusco, Marnie L; Bornholdt, Zachary A; Lee, Jeffrey E; Flyak, Andrew I; Matsuoka, Rei; Kohda, Daisuke; Yanagi, Yusuke; Hammel, Michal; Crowe, James E; Saphire, Erica Ollmann

    2015-02-26

    The filoviruses, including Marburg and Ebola, express a single glycoprotein on their surface, termed GP, which is responsible for attachment and entry of target cells. Filovirus GPs differ by up to 70% in protein sequence, and no antibodies are yet described that cross-react among them. Here, we present the 3.6 Å crystal structure of Marburg virus GP in complex with a cross-reactive antibody from a human survivor, and a lower resolution structure of the antibody bound to Ebola virus GP. The antibody, MR78, recognizes a GP1 epitope conserved across the filovirus family, which likely represents the binding site of their NPC1 receptor. Indeed, MR78 blocks binding of the essential NPC1 domain C. These structures and additional small-angle X-ray scattering of mucin-containing MARV and EBOV GPs suggest why such antibodies were not previously elicited in studies of Ebola virus, and provide critical templates for development of immunotherapeutics and inhibitors of entry.

  6. Antibody reactivity to the major fish allergen parvalbumin is determined by isoforms and impact of thermal processing.

    Science.gov (United States)

    Saptarshi, Shruti R; Sharp, Michael F; Kamath, Sandip D; Lopata, Andreas L

    2014-04-01

    The EF-hand calcium binding protein, parvalbumin, is a major fish allergen. Detection of this allergen is often difficult due to its structural diversity among various fish species. The aim of this study was to evaluate the cross-reactivity of parvalbumin in a comprehensive range of bony and cartilaginous fish, from the Asia-Pacific region, and conduct a molecular analysis of this highly allergenic protein. Using the monoclonal anti-parvalbumin antibody PARV-19, we demonstrated the presence of monomeric and oligomeric parvalbumin in all fish analysed, except for gummy shark a cartilaginous fish. Heat processing of this allergen greatly affected its antibody reactivity. While heating caused a reduction in antibody reactivity to multimeric forms of parvalbumins for most bony fish, a complete loss of reactivity was observed for cartilaginous fish. Molecular analysis demonstrated that parvalbumin cross-reactivity, among fish species, is due to the molecular phylogenetic association of this major fish allergen.

  7. Direct-acting antiviral treatment in adults infected with hepatitis C virus: Reactivation of hepatitis B virus coinfection as a further challenge.

    Science.gov (United States)

    De Monte, Anne; Courjon, Johan; Anty, Rodolphe; Cua, Eric; Naqvi, Alissa; Mondain, Véronique; Cottalorda, Jacqueline; Ollier, Laurence; Giordanengo, Valérie

    2016-05-01

    Use of direct-acting antiviral drugs (DAAs) greatly improves management of adults infected with hepatitis C virus (HCV) whether patients are treatment-naive or unsuccessfully pre-treated. Several inhibitors of viral nonstructural proteins (NS3/4A protease, NS5A and NS5B polymerase) allow a rapid HCV clearance and increase rates of sustained virological response. Both the EASL and AASLD guidelines have recently published up-to-date recommendations for their use, addressing each HCV genotype and particular situations. However, management of patients coinfected with hepatitis B virus (HBV) has been developed by these guidelines with reference to cases of HBV reactivation reported during previous anti-HCV regimens containing interferon known active against both HBV and HCV. In the setting of the interferon-free HCV therapies with DAAs only, the possibility of HBV reactivation during treatment of hepatitis C is raised due to viral interferences in HCV/HBV coinfected persons. Herein, we report a case of early HBV reactivation during DAAs-based anti-HCV treatment (ledipasvir/sofosbuvir) in a patient having a resolved HBV infection and chronically infected with HCV genotype 4 and HIV. Moreover, we review similar recent cases of HBV reactivation in patients infected with HBV and HCV genotype 1 during treatment of hepatitis C by regimen incorporating other combination of DAAs (sofosbuvir/simeprevir or daclatasvir/asunaprevir). Due to the potential risk of early HBV reactivation in HCV/HBV-coinfected patients during interferon-free DAAs-based HCV therapies, altogether these cases highlight the necessity to closely monitor HBV coinfection, regardless its stage (chronic, occult, resolved), whatever HCV genotype or class of DAAs used.

  8. Reactivity of Human Preformed Natural Antibodies with Various Porcine Pancreatic Cells

    Institute of Scientific and Technical Information of China (English)

    张伟杰; 熊沛; 刘绍春

    2001-01-01

    The reactivity of human preformed natural antibodies (PNAbs) with various porcine pancreatic cells and its isotypes was investigated. Eighteen serum samples from patients with insulin-dependent diabetes mellitus (IDDM) and 20 serum samples from healthy human subjects were collected. The frozen sections of the pig pancreas were incubated with these sera, and subsequently incubated with FITC-conjugated goat antihuman IgG and IgM monoclonal antibodies. The reactivity of human PNAbs with various porcine pancreatic cells was determined by indirect immunofluorescence staining technique. The results showed that 55.6 % of IDDM patients and 55.0 % of healthy human individuals contained PNAbs against porcine endocrine cells. However, the percentage of strongly reacting sera in the patient group was significantly increased as compared with that in the control group. All used sera from IDDM patients and 95 % of sera from healthy controls could react to one or more of the various pancreatic cell types, including: endocrine cells, exocrine cells, vascular endothelial cells, ductal epithelial cells and macrophages. The isotypes of PNAbs contained both IgG and IgM. In view of strongly positive reactivity of PNAbs with various porcine pancreatic cells, pretransplantly cross-matching test and graft pretreatment may be necessary for survival of islet transplants.

  9. Effective Binding of a Phosphatidylserine-Targeting Antibody to Ebola Virus Infected Cells and Purified Virions

    Science.gov (United States)

    Dowall, S. D.; Graham, V. A.; Corbin-Lickfett, K.; Empig, C.; Schlunegger, K.; Bruce, C. B.; Easterbrook, L.; Hewson, R.

    2015-01-01

    Ebola virus is responsible for causing severe hemorrhagic fevers, with case fatality rates of up to 90%. Currently, no antiviral or vaccine is licensed against Ebola virus. A phosphatidylserine-targeting antibody (PGN401, bavituximab) has previously been shown to have broad-spectrum antiviral activity. Here, we demonstrate that PGN401 specifically binds to Ebola virus and recognizes infected cells. Our study provides the first evidence of phosphatidylserine-targeting antibody reactivity against Ebola virus. PMID:25815346

  10. Effective Binding of a Phosphatidylserine-Targeting Antibody to Ebola Virus Infected Cells and Purified Virions

    Directory of Open Access Journals (Sweden)

    S. D. Dowall

    2015-01-01

    Full Text Available Ebola virus is responsible for causing severe hemorrhagic fevers, with case fatality rates of up to 90%. Currently, no antiviral or vaccine is licensed against Ebola virus. A phosphatidylserine-targeting antibody (PGN401, bavituximab has previously been shown to have broad-spectrum antiviral activity. Here, we demonstrate that PGN401 specifically binds to Ebola virus and recognizes infected cells. Our study provides the first evidence of phosphatidylserine-targeting antibody reactivity against Ebola virus.

  11. Reactive oxygen species induced by therapeutic CD20 antibodies inhibit natural killer cell-mediated antibody-dependent cellular cytotoxicity against primary CLL cells

    Science.gov (United States)

    Werlenius, Olle; Aurelius, Johan; Hallner, Alexander; Akhiani, Ali A.; Simpanen, Maria; Martner, Anna; Andersson, Per-Ola; Hellstrand, Kristoffer; Thorén, Fredrik B.

    2016-01-01

    The antibody-dependent cellular cytotoxicity (ADCC) of natural killer (NK) cells is assumed to contribute to the clinical efficacy of monoclonal antibodies (mAbs) in chronic lymphocytic leukemia (CLL) and other hematopoietic malignancies of B cell origin. We sought to determine whether reactive oxygen species (ROS)-producing monocytes regulate the ADCC of NK cells against primary CLL cells using anti-CD20 as the linking antibody. The monoclonal CD20 antibodies rituximab and ofatumumab were found to trigger substantial release of ROS from monocytes. Antibody-exposed monocytes induced NK cell apoptosis and restricted NK cell-mediated ADCC against autologous CLL cells. The presence of inhibitors of ROS formation and scavengers of ROS preserved NK cell viability and restored NK cell-mediated ADCC against primary CLL cells. We propose that limiting the antibody-induced induction of immunosuppressive ROS may improve the anti-leukemic efficacy of anti-CD20 therapy in CLL. PMID:27097113

  12. A cross-reactive monoclonal antibody to nematode haemoglobin enhances protective immune responses to Nippostrongylus brasiliensis.

    Directory of Open Access Journals (Sweden)

    Natalie E Nieuwenhuizen

    Full Text Available BACKGROUND: Nematode secreted haemoglobins have unusually high affinity for oxygen and possess nitric oxide deoxygenase, and catalase activity thought to be important in protection against host immune responses to infection. In this study, we generated a monoclonal antibody (48Eg against haemoglobin of the nematode Anisakis pegreffii, and aimed to characterize cross-reactivity of 4E8g against haemoglobins of different nematodes and its potential to mediate protective immunity against a murine hookworm infection. METHODOLOGY/PRINCIPAL FINDINGS: Immunoprecipitation was used to isolate the 4E8g-binding antigen in Anisakis and Ascaris extracts, which were identified as haemoglobins by peptide mass fingerprinting and MS/MS. Immunological cross-reactivity was also demonstrated with haemoglobin of the rodent hookworm N. brasiliensis. Immunogenicity of nematode haemoglobin in mice and humans was tested by immunoblotting. Anisakis haemoglobin was recognized by IgG and IgE antibodies of Anisakis-infected mice, while Ascaris haemoglobin was recognized by IgG but not IgE antibodies in mouse and human sera. Sequencing of Anisakis haemoglobin revealed high similarity to haemoglobin of a related marine nematode, Psuedoterranova decipiens, which lacks the four -HKEE repeats of Ascaris haemoglobin important in octamer assembly. The localization of haemoglobin in the different parasites was examined by immunohistochemistry and associated with the excretory-secretary ducts in Anisakis, Ascaris and N. brasiliensis. Anisakis haemoglobin was strongly expressed in the L3 stage, unlike Ascaris haemoglobin, which is reportedly mainly expressed in adult worms. Passive immunization of mice with 4E8g prior to infection with N. brasiliensis enhanced protective Th2 immunity and led to a significant decrease in worm burdens. CONCLUSION: The monoclonal antibody 4E8g targets haemoglobin in broadly equivalent anatomical locations in parasitic nematodes and enhances host immunity

  13. Dengue serotype cross-reactive, anti-E protein antibodies confound specific immune memory for one year after infection

    Directory of Open Access Journals (Sweden)

    Ying Xiu eToh

    2014-08-01

    Full Text Available Dengue virus has four serotypes and is endemic globally in tropical countries. Neither a specific treatment nor an approved vaccine is available, and correlates of protection are not established. The standard neutralization assay cannot differentiate between serotype-specific and serotype cross-reactive antibodies in patients early after infection, leading to an overestimation of the long-term serotype-specific protection of an antibody response. It is known that the cross-reactive response in patients is temporary but few studies have assessed kinetics and potential changes in serum antibody specificity over time. To better define the specificity of polyclonal antibodies during disease and after recovery, longitudinal samples from patients with primary or secondary DENV-2 infection were collected over a period of one year. We found that serotype cross-reactive antibodies peaked three weeks after infection and subsided within one year. Since secondary patients rapidly produced antibodies specific for the virus envelope (E protein, an E-specific ELISA was superior compared to a virus particle-specific ELISA to identify patients with secondary infections. Dengue infection triggered a massive activation and mobilization of both naïve and memory B cells possibly from lymphoid organs into the blood, providing an explanation for the surge of circulating plasmablasts and the increase in cross-reactive E protein-specific antibodies.

  14. Differential reactivity of mouse monoclonal anti-HBs antibodies with recombinant mutant HBs antigens

    Institute of Scientific and Technical Information of China (English)

    Azam Roohi; Yaghoub Yazdani; Jalal Khoshnoodi; Seyed Mohammad Jazayeri; William F Carman; Mahmood Chamankhah; Manley Rashedan; Fazel Shokri

    2006-01-01

    AIM: To investigate the reactivity of a panel of 8 mouse anti-hepatitis B surface antigen (HBsAg) monoclonal antibodies (mAbs) using a collection of 9 recombinant HBsAg mutants with a variety of amino acid substitutions mostly located within the "a" region.METHODS: The entire HBs genes previously cloned into a mammalian expression vector were transiently transfected into COS7 cells. Two standard unmutated sequences of the ayw and adw subtypes served as controls. Secreted mutant proteins were collected and measured by three commercial diagnostic immunoassays to assess transfection efficiency. Reactivity of anti-HBs mAbs with mutated HBsAgs was determined by sandwich enzyme-linked immunosorbent assay (ELISA).RESULTS: Reactivity of anti-HBs mAbs with mutated HBsAgs revealed different patterns. While three mutants reacted strongly with all mAbs, two mutants reacted weakly with only two mAbs and the remaining proteins displayed variable degrees of reactivity towards different mAbs. Accordingly, four groups of mAbs with different but overlapping reactivity patterns could be envisaged. One group consisting of two mAbs (37C5-S7 and 35C6-S11) was found to recognize stable linear epitopes conserved in all mutants. Mutations outside the "a"determinant at positions 120 (P→S), 123(T→N) and 161(M→T) were found to affect reactivity of these mAbs.CONCLUSION: Our findings could have important implications for biophysical studies, vaccination strategies and immunotherapy of hepatitis B virus (HBV) mutants.

  15. Packageable antiviral therapeutics against human immunodeficiency virus type 1: virion-targeted virus inactivation by incorporation of a single-chain antibody against viral integrase into progeny virions.

    Science.gov (United States)

    Okui, N; Sakuma, R; Kobayashi, N; Yoshikura, H; Kitamura, T; Chiba, J; Kitamura, Y

    2000-03-01

    To determine their activities as an antiviral agent packageable within virions and suitable for continued expression in cells, we tested a single-chain antibody (scAb) against human immunodeficiency virus type 1 (HIV-1) integrase and its three fusion proteins: fused to viral protein R (scab-Vpr), a double-cassette of the WXXF motif binding to Vpr (scAb-WXXF), and viral major capsid protein (scAb-CA), respectively. Cotransfection of human 293T cells with expression plasmid for scAb-Vpr or -WXXF along with HIV-1 clone pLAI resulted in the production of a normal amount of progeny virions with infectivity decreased by more than 10(3)-fold. Immunoblot analyses showed that scAb-Vpr or -WXXF was associated with virions, whereas scAb or scAb-CA was not, suggesting that scAb-Vpr or -WXXF was incorporated into virions. The incorporation of scAb-WXXF appeared to be Vpr dependent, because the fusion protein was associated with the wild-type but not with Vpr-truncated HIV-1 virions. Since G418-selected HeLa clones carrying expression plasmid for scAb-WXXF were obtained much more frequently than those for scAb-Vpr, scAb-WXXF was inferred to be less toxic to cells than scAb-Vpr. These results suggest that scAb-WXXF may serve as a novel class of antiviral therapeutic that inactivates progeny HIV virions from within.

  16. Natural and Immune Human Antibodies Reactive with Antigens of Virulent Neisseria gonorrhoeae: Immunoglobulins G, M, and A

    Science.gov (United States)

    Cohen, Irun R.

    1967-01-01

    Natural and immune human antibodies reactive with heat-labile and heat-stable antigens of virulent Neisseria gonorrhoeae were studied by use of an indirect fluorescent-antibody (IFA) procedure. The immunoglobulin class of the reactive antibodies was identified by using fluorescein-conjugated antisera specific for human IgG, IgA, or IgM in the IFA procedure. The effects of heat and mercaptoethanol on IFA reactivities were also studied. It appeared that antibodies of the IgG, IgM, and IgA classes present in the sera of both infected persons (immune antibodies) and normal persons with no history of gonococcal infection (natural antibodies) react with heat-stable somatic antigens. Immune IgG antibodies, however, were distinguishable from natural IgG antibodies by their ability to recognize heat-labile surface antigens. The distinction between natural and immune IgM antibodies was less obvious. IgM antibodies from both infected and normal persons appeared to react with heat-labile antigens. Some, but not all, infected persons had immune IgA antibodies to heat-labile as well as to heat-stable antigens. Treatment of sera with mercaptoethanol had no effect on IgG antibodies. The IFA activity of IgM antibodies was decreased, but not abolished. The effects of mercaptoethanol on IgA antibodies were variable. Some sera showed a decrease in IgA titer, and others showed an increase in IgA activity to certain antigens. Immune IgG antibodies were more resistant to heating than were natural IgG antibodies. Natural and immune IgM antibodies appeared equally sensitive to heating. IgA activity, on the other hand, was increased by heating sera at 60 C, but was decreased at higher temperatures. Thus, it appears that natural and immune human IgG antibodies to N. gonorrhoeae may be distinguished by their interactions with heat-labile antigens and by their resistance to heating. Images PMID:4961630

  17. New broadly reactive neutralizing antibodies against hepatitis B virus surface antigen.

    Science.gov (United States)

    Kucinskaite-Kodze, Indre; Pleckaityte, Milda; Bremer, Corinna M; Seiz, Pia L; Zilnyte, Milda; Bulavaite, Aiste; Mickiene, Gitana; Zvirblis, Gintautas; Sasnauskas, Kestutis; Glebe, Dieter; Zvirbliene, Aurelija

    2016-01-01

    Hepatitis B virus (HBV) surface antigen (HBsAg) is considered to be the most important target for the diagnosis and immune prophylaxis of HBV infection. HBsAg-specific monoclonal antibodies (MAbs) are extensively used for studying the complex structure of the HBsAg, mapping the neutralizing epitopes and development of HBV diagnostic tests. However, the efficiency of anti-HBV binding strongly depends on the epitope structure and MAb capability to recognize different HBV variants. In the current study, 9 MAbs against yeast-expressed HBsAg of ayw2 serotype were generated and 7 of them were shown to recognize a linear epitope comprising amino acid (aa) residues 119-GPCRTCT-125 within the main antigenic "a" determinant of HBsAg. One MAb of the highest affinity (clone HB1) was selected for detailed cross-reactivity studies, generation of recombinant single-chain antibody (scFv) and molecular modelling of antibody-epitope interaction. The importance of each aa residue within the identified MAb epitope was determined by alanine substitution study that revealed aa residues C(121), T(123), C(124) and T(125) as essential for binding. These aa residues are highly conserved among HBV variants. In contrast, alanine substitution of G119, P120 and R122 had no or minor influence on the reactivity with the MAb. Certain aa residues at position 122 (either R or K) define different HBV serotypes (either d or y), therefore, the affinity of the MAb HB1 for the epitope with R122K substitution was determined to evaluate its diagnostic potential. The MAb recognized both epitope variants with high affinity. Sequence alignment of the MAb epitope within different HBV strains demonstrated that the shortest peptide recognized by the MAb 121-CR(K)TCT-125 is identical among different human HBV genotypes (HBV A-F, H) and monkey HBV species (HBVCP, HBVGO, HBVGB, WMHBV). In line with these data, the MAb HB1 was cross-reactive in Western blot with a large panel of antigens derived from different HBV

  18. Novel monoclonal antibodies broadly reactive to human recombinant sapovirus-like particles.

    Science.gov (United States)

    Kitamoto, Noritoshi; Oka, Tomoichiro; Katayama, Kazuhiko; Li, Tian-Cheng; Takeda, Naokazu; Kato, Yoji; Miyoshi, Tatsuya; Tanaka, Tomoyuki

    2012-11-01

    Sapovirus (SaV), a member of the family Caliciviridae, is an important cause of acute epidemic gastroenteritis in humans. Human SaV is genetically and antigenically diverse and can be classified into four genogroups (GI, GII, GIV, and GV) and 16 genotypes (7 GI [GI.1-7], 7 GII, [GII.1-7], 1 GIV and 1 GV), based on capsid sequence similarities. Monoclonal antibodies (MAbs) are powerful tools for examining viruses and proteins. PAI myeloma cells were fused with spleen cells from mice immunized with a single type of recombinant human SaV virus-like particles (VLPs) (GI.1, GI.5, GI.6, GII.3, GIV, or GV). Sixty-five hybrid clones producing MAbs were obtained. Twenty-four MAbs were characterized by ELISA, according to their cross-reactivity to each VLP (GI.1, GI.5, GI.6, GII.2, GII.3, GII.4, GII.7, GIV, and GV). The MAbs were classified by this method into: (i) MAbs broadly cross-reactive to all GI, GII, GIV and GV strains; (ii) those reactive in a genogroup-specific; and (iii) those reactive in a genotype-specific manner. Further analysis of three broadly cross-reactive MAbs with a competitive ELISA demonstrated that at least two different common epitopes are located on the capsid protein of human SaVs in the four genogroups. The MAbs generated and characterized in this study will be useful tools for further study of the antigenic and structural topography of the human SaV virion and for developing new diagnostic assays for human SaV. © 2012 The Societies and Wiley Publishing Asia Pty Ltd.

  19. Cross-reactive saliva IgA antibodies to oxidized LDL and periodontal pathogens in humans.

    Science.gov (United States)

    Akhi, Ramin; Wang, Chunguang; Kyrklund, Mikael; Kummu, Outi; Turunen, Sini Pauliina; Hyvärinen, Kati; Kullaa, Arja; Salo, Tuula; Pussinen, Pirkko J; Hörkkö, Sohvi

    2017-07-01

    Oxidized low-density lipoproteins (oxLDL) are formed as a result of lipid peroxidation and are highly immunogenic and proatherogenic. In this study, saliva antibodies binding to oxLDL, Porphyromonas gingivalis (Pg) and Aggregatibacter actinomycetemcomitans (Aa) were characterized and their cross-reactivity was evaluated. Resting and stimulated saliva samples were collected from 36 healthy adults (mean age 26 years). Saliva IgA, IgG and IgM autoantibody levels to copper oxidized LDL (CuOx-LDL) and malondialdehyde acetaldehyde-modified LDL (MAA-LDL) were determined with chemiluminescence immunoassay. Saliva IgA and IgG antibodies binding to MAA-LDL and CuOx-LDL were detected in all samples and they were associated with the saliva levels of IgA and IgG to P. gingivalis and A. actinomycetemcomitans. Competitive immunoassay showed that saliva antibodies to MAA-LDL cross-reacted specifically with P. gingivalis. The autoantibody levels to oxLDL in saliva were not associated with the autoantibody levels to oxLDL in plasma or with saliva apolipoprotein B 100 levels. Saliva contains IgA and IgG binding to oxLDL, which showed cross-reactive properties with the periodontal pathogens Porphyromonas gingivalis (P.g). The data suggest that secretory IgA to P.g may participate in immune reactions involved in LDL oxidation through molecular mimicry. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Antibodies with specificity for native and denatured forms of ovalbumin differ in reactivity between enzyme-linked immunosorbent assays

    DEFF Research Database (Denmark)

    Holm, B. E.; Bergmann, Ann Christina; Hansen, Paul Robert

    2015-01-01

    In this study, polyclonal and monoclonal antibodies to native and denatured chicken ovalbumin (OVA) were produced to compare their dependency on continuous and three-dimensional epitopes. These antibodies were characterized with respect to reactivity to native and denatured OVA by enzyme......-linked immunosorbent assay (ELISA) employing surface-bound OVA and streptavidin-capture ELISA to determine whether effects of different coating influence antibody specificity and with respect to epitope specificity by peptide ELISA, using overlapping peptides, covering the complete OVA sequence. Polyclonal antibodies...... to native OVA reacted strongly with native and denatured OVA in both assays, but did not react with the overlapping peptides. Polyclonal antibodies to denatured OVA reacted strongly with both OVA forms and with several of the overlapping peptides. Monoclonal antibodies to native OVA reacted preferentially...

  1. A cell-penetrating antibody fragment against HIV-1 Rev has high antiviral activity: characterization of the paratope.

    Science.gov (United States)

    Zhuang, Xiaolei; Stahl, Stephen J; Watts, Norman R; DiMattia, Michael A; Steven, Alasdair C; Wingfield, Paul T

    2014-07-18

    The HIV-1 protein Rev oligomerizes on viral transcripts and directs their nuclear export. Previously, a Fab against Rev generated by phage display was used to crystallize and solve the structure of the Rev oligomerization domain. Here we have investigated the capability of this Fab to block Rev oligomerization and inhibit HIV-1 replication. The Fab itself did not have antiviral activity, but when a Tat-derived cell-penetrating peptide was appended, the resulting molecule (FabRev1-Tat) was strongly inhibitory of three different CCR5-tropic HIV-1 isolates (IC50 = 0.09-0.44 μg/ml), as assessed by suppression of reverse transcriptase activity in infected peripheral blood mononuclear cells, and had low cell toxicity (TC50 > 100 μg/ml). FabRev1-Tat was taken up by both peripheral blood mononuclear and HEK293T cells, appearing in both the cytoplasm and nucleus, as shown by immunofluorescence confocal laser scanning microscopy. Computational alanine scanning was used to identify key residues in the complementarity-determining regions to guide mutagenesis experiments. Residues in the light chain CDR3 (LCDR3) were assessed to be important. Residues in LCDR3 were mutated, and LCDR3-Tyr(92) was found to be critical for binding to Rev, as judged by surface plasmon resonance and electron microscopy. Peptides corresponding to all six CDR regions were synthesized and tested for Rev binding. None of the linear peptides had significant affinity for Rev, but four of the amide-cyclic forms did. Especially cyclic-LCDR3 (LGGYPAASYRTA) had high affinity for Rev and was able to effectively depolymerize Rev filaments, as shown by both surface plasmon resonance and electron microscopy.

  2. The epitope and neutralization mechanism of AVFluIgG01, a broad-reactive human monoclonal antibody against H5N1 influenza virus.

    Directory of Open Access Journals (Sweden)

    Zhiliang Cao

    Full Text Available The continued spread of highly pathogenic avian influenza (HPAI H5N1 virus underscores the importance of effective antiviral approaches. AVFluIgG01 is a potent and broad-reactive H5N1-neutralizing human monoclonal antibody (mAb showing great potential for use either for therapeutic purposes or as a basis of vaccine development, but its antigenic epitope and neutralization mechanism have not been finely characterized. In this study, we first demonstrated that AVFluIgG01 targets a novel conformation-dependent epitope in the globular head region of H5N1 hemagglutinin (HA. By selecting mimotopes from a random peptide library in combination with computational algorithms and site-directed mutagenesis, the epitope was mapped to three conserved discontinuous sites (I-III that are located closely at the three-dimensional structure of HA. Further, we found that this HA1-specific human mAb can efficiently block both virus-receptor binding and post-attachment steps, while its Fab fragment exerts the post-attachment inhibition only. Consistently, AVFluIgG01 could inhibit HA-mediated cell-cell membrane fusion at a dose-dependent manner and block the acquisition of pH-induced protease sensitivity. These results suggest a neutralization mechanism of AVFluIgG01 by simultaneously blocking viral attachment to the receptors on host cells and interfering with HA conformational rearrangements associated with membrane fusion. The presented data provide critical information for developing novel antiviral therapeutics and vaccines against HPAI H5N1 virus.

  3. Toward Effective HIV Vaccination INDUCTION OF BINARY EPITOPE REACTIVE ANTIBODIES WITH BROAD HIV NEUTRALIZING ACTIVITY

    Energy Technology Data Exchange (ETDEWEB)

    Nishiyama, Yasuhiro; Planque, Stephanie; Mitsuda, Yukie; Nitti, Giovanni; Taguchi, Hiroaki; Jin, Lei; Symersky, Jindrich; Boivin, Stephane; Sienczyk, Marcin; Salas, Maria; Hanson, Carl V.; Paul, Sudhir; (Texas-MED); (Viral Rickettsial)

    2009-11-23

    We describe murine monoclonal antibodies (mAbs) raised by immunization with an electrophilic gp120 analog (E-gp120) expressing the rare ability to neutralize genetically heterologous human immunodeficiency virus (HIV) strains. Unlike gp120, E-gp120 formed covalent oligomers. The reactivity of gp120 and E-gp120 with mAbs to reference neutralizing epitopes was markedly different, indicating their divergent structures. Epitope mapping with synthetic peptides and electrophilic peptide analogs indicated binary recognition of two distinct gp120 regions by anti-E-gp120 mAbs, the 421-433 and 288-306 peptide regions. Univalent Fab and single chain Fv fragments expressed the ability to recognize both peptides. X-ray crystallography of an anti-E-gp120 Fab fragment revealed two neighboring cavities, the typical antigen-binding cavity formed by the complementarity determining regions (CDRs) and another cavity dominated by antibody heavy chain variable (VH) domain framework (FR) residues. Substitution of the FR cavity VH Lys-19 residue by an Ala residue resulted in attenuated binding of the 421-433 region peptide probe. The CDRs and VH FR replacement/silent mutation ratios exceeded the ratio for a random mutation process, suggesting adaptive development of both putative binding sites. All mAbs studied were derived from VH1 family genes, suggesting biased recruitment of the V gene germ line repertoire by E-gp120. The conserved 421-433 region of gp120 is essential for HIV binding to host CD4 receptors. This region is recognized weakly by the FR of antibodies produced without exposure to HIV, but it usually fails to induce adaptive synthesis of neutralizing antibodies. We present models accounting for improved CD4-binding site recognition and broad HIV neutralizing activity of the mAbs, long sought goals in HIV vaccine development.

  4. Anti-M antibodies: Biphasic (reactive at room temperature and at 37°C): A case series.

    Science.gov (United States)

    Shah, Siddhi P; Kalgutkar, Sangeeta M; Sawant, Rajesh B; Deshpande, Anand S

    2016-01-01

    Anti-M antibody, which is not reactive at 37°C, is not clinically significant. Reports of clinically significant anti-M antibodies causing hemolytic disease of the fetus and the newborn (HDFN) and delayed hemolytic transfusion reaction (DHTR) are available. We report 13 cases of anti-M antibodies reactive at room temperature (RT) and at 37°C. These were found in patients of varied age groups (11 months to 85 years) with varied clinical diagnosis. All the female patients were multigravida. In all cases, antibody screening was positive at RT as well as at the indirect antiglobulin test (IAT) phase. Providing "M"-antigen negative transfusions is the best therapy in this situation. Provision of red blood cell (RBC) antigen phenotyped donor registry shall ensure quick provision of antigen-negative blood for transfusion in emergency situations.

  5. [Reactivity of antibodies to collagen types I to IV and antibodies to chondroitin sulfate in the spleen].

    Science.gov (United States)

    Galbavý, S; Ruzicková, M; Surmíková, E; Danihel, L; Porubský, J; Papincák, J; Holesa, S; Trnka, J

    1996-02-01

    Antibodies to collagen type I and III reacted negatively, antibodies to collagen type IV positively with reticulin, trabeculae and circumferent reticulum of lymphatic sheaths, poorly positively with capsula, strongly positively with subcapsular zone. Antibodies to collagen type II reacted positively with capsula, poorly with subcapsular zone, strongly with sinus wall and poorly with trabeculae. They did not react with circumferent reticulum of periarterial lymphoid sheaths. Antibodies to collagen type II and IV reacted positively with central arteries. Antibodies to chondroitinsulphate C reacted poorly and antibodies to chondroitinsulphate B strongly positively with sinus walls and oval cells spread in the white and red pulpa. Antibodies to chondroitin sulphate A reacted similarly as antibodies to chondroitinsulphate B.

  6. Induction and characterization of monoclonal anti-idiotypic antibodies reactive with idiotopes of canine parvovirus neutralizing monoclonal antibodies.

    NARCIS (Netherlands)

    G.F. Rimmelzwaan (Guus); J. van Es (Johan); G.A. Drost; F.G.C.M. Uytdehaag (Fons); A.D.M.E. Osterhaus (Albert)

    1991-01-01

    textabstractMonoclonal anti-idiotypic (anti-Id) antibodies (Ab2) were generated against idiotypes (Id) of canine parvovirus (CPV) specific monoclonal antibodies (MoAbs). The binding of most of these anti-Id antibodies to their corresponding Id could be inhibited by antigen, thus classifying these an

  7. Soluble tumour necrosis factor (TNF)-receptor levels in serum as markers of anti-viral host reactivity

    DEFF Research Database (Denmark)

    Bartholdy, C; Nansen, A; Marker, O

    1999-01-01

    The role of soluble receptors for TNF-alpha (sTNF-Rs) as markers of virus-induced host responses was studied by the use of murine model infections. A marked elevation in serum levels of sTNF-R75, but not sTNF-R55, was found 1 day after infection with vesicular stomatitis virus (VSV). In mice......-gamma. A simple correlation between release of sTNF-Rs in vivo and macrophage activation in vitro was not present. These findings indicate that sTNF-R75 is indeed a sensitive marker of both innate and specific cell-mediated host reactivity during viral infection, but it is not correlated to a single immunological...

  8. Reactivity of circulating antineuronal antibodies (CANA) on peripheral nervous system structures.

    Science.gov (United States)

    Grisold, W; Drlicek, M; Liszka, U; Jellinger, K; Popp, W

    1988-01-01

    The appearance of circulating antineuronal antibodies (CANA) in patients with malignant tumors has been correlated with the occurrence of paraneoplastic neurological syndromes. However, the effect of CANA on the peripheral nervous system is poorly understood. The reactivity of sera from CANA-positive and -negative patients were investigated on cryostat sections of peripheral nerves and skeletal muscle, and on nerve tease-fiber preparations. Only CANA-positive sera showed staining of Schwann cell nuclei on cryostat sections, whereas nerve tease-fiber preparations and sections of skeletal muscle remained negative. Positive direct immunofluorescence of small cell lung cancer (SCLS) cells was confined to CANA-positive patients only. These findings suggest the existence of a common antigen between SCLC and Schwann cells.

  9. A monoclonal antibody reactive with normal and leukemic human myeloid progenitor cells.

    Science.gov (United States)

    Griffin, J D; Linch, D; Sabbath, K; Larcom, P; Schlossman, S F

    1984-01-01

    Anti-MY9 is an IgG2b murine monoclonal antibody selected for reactivity with immature normal human myeloid cells. The MY9 antigen is expressed by blasts, promyelocytes and myelocytes in the bone marrow, and by monocytes in the peripheral blood. Erythrocytes, lymphocytes and platelets are MY9 negative. All myeloid colony-forming cells (CFU-GM), a fraction of erythroid burst-forming cells (BFU-E) and multipotent progenitors (CFU-GEMM) are MY9 positive. This antigen is further expressed by the leukemic cells of a majority of patients with AML and myeloid CML-BC. Leukemic stem cells (leukemic colony-forming cells, L-CFC) from most patients tested were also MY9 positive. In contrast, MY9 was not detected on lymphocytic leukemias. Anti-MY9 may be a valuable reagent for the purification of hematopoietic colony-forming cells and for the diagnosis of myeloid-lineage leukemias.

  10. Cross-reactive antibodies in convalescent SARS patients' sera against the emerging novel human coronavirus EMC (2012) by both immunofluorescent and neutralizing antibody tests.

    Science.gov (United States)

    Chan, Kwok-Hung; Chan, Jasper Fuk-Woo; Tse, Herman; Chen, Honglin; Lau, Candy Choi-Yi; Cai, Jian-Piao; Tsang, Alan Ka-Lun; Xiao, Xincai; To, Kelvin Kai-Wang; Lau, Susanna Kar-Pui; Woo, Patrick Chiu-Yat; Zheng, Bo-Jiang; Wang, Ming; Yuen, Kwok-Yung

    2013-08-01

    A severe acute respiratory syndrome (SARS)-like disease due to a novel betacoronavirus, human coronavirus EMC (HCoV-EMC), has emerged recently. HCoV-EMC is phylogenetically closely related to Tylonycteris-bat-coronavirus-HKU4 and Pipistrellus-bat-coronavirus-HKU5 in Hong Kong. We conducted a seroprevalence study on archived sera from 94 game-food animal handlers at a wild life market, 28 SARS patients, and 152 healthy blood donors in Southern China to assess the zoonotic potential and evidence for intrusion of HCoV-EMC and related viruses into humans. Anti-HCoV-EMC and anti-SARS-CoV antibodies were detected using screening indirect immunofluorescence (IF) and confirmatory neutralizing antibody tests. Two (2.1%) animal handlers had IF antibody titer of ≥ 1:20 against both HCoV-EMC and SARS-CoV with neutralizing antibody titer of SARS patients had significant IF antibody titers with 7/28 (25%) having anti-HCoV-EMC neutralizing antibodies at low titers which significantly correlated with that of HCoV-OC43. Bioinformatics analysis demonstrated a significant B-cell epitope overlapping the heptad repeat-2 region of Spike protein. Virulence of SARS-CoV over other betacoronaviruses may boost cross-reactive neutralizing antibodies against other betacoronaviruses. Convalescent SARS sera may contain cross-reactive antibodies against other betacoronaviruses and confound seroprevalence study for HCoV-EMC. Copyright © 2013 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  11. Exploiting cross-reactivity to neutralize two different scorpion venoms with one single chain antibody fragment.

    Science.gov (United States)

    Riaño-Umbarila, Lidia; Contreras-Ferrat, Gabriel; Olamendi-Portugal, Timoteo; Morelos-Juárez, Citlalli; Corzo, Gerardo; Possani, Lourival D; Becerril, Baltazar

    2011-02-25

    We report the optimization of a family of human single chain antibody fragments (scFv) for neutralizing two scorpion venoms. The parental scFv 3F recognizes the main toxins of Centruroides noxius Hoffmann (Cn2) and Centruroides suffusus suffusus (Css2), albeit with low affinity. This scFv was subjected to independent processes of directed evolution to improve its recognition toward Cn2 (Riaño-Umbarila, L., Juárez-González, V. R., Olamendi-Portugal, T., Ortíz-León, M., Possani, L. D., and Becerril, B. (2005) FEBS J. 272, 2591-2601) and Css2 (this work). Each evolved variant showed strong cross-reactivity against several toxins, and was capable of neutralizing Cn2 and Css2. Furthermore, each variant neutralized the whole venoms of the above species. As far as we know, this is the first report of antibodies with such characteristics. Maturation processes revealed key residue changes to attain expression, stability, and affinity improvements as compared with the parental scFv. Combination of these changes resulted in the scFv LR, which is capable of rescuing mice from severe envenomation by 3 LD(50) of freshly prepared whole venom of C. noxius (7.5 μg/20 g of mouse) and C. suffusus (26.25 μg/20 g of mouse), with surviving rates between 90 and 100%. Our research is leading to the formulation of an antivenom consisting of a discrete number of human scFvs endowed with strong cross-reactivity and low immunogenicity.

  12. Exploiting Cross-reactivity to Neutralize Two Different Scorpion Venoms with One Single Chain Antibody Fragment*

    Science.gov (United States)

    Riaño-Umbarila, Lidia; Contreras-Ferrat, Gabriel; Olamendi-Portugal, Timoteo; Morelos-Juárez, Citlalli; Corzo, Gerardo; Possani, Lourival D.; Becerril, Baltazar

    2011-01-01

    We report the optimization of a family of human single chain antibody fragments (scFv) for neutralizing two scorpion venoms. The parental scFv 3F recognizes the main toxins of Centruroides noxius Hoffmann (Cn2) and Centruroides suffusus suffusus (Css2), albeit with low affinity. This scFv was subjected to independent processes of directed evolution to improve its recognition toward Cn2 (Riaño-Umbarila, L., Juárez-González, V. R., Olamendi-Portugal, T., Ortíz-León, M., Possani, L. D., and Becerril, B. (2005) FEBS J. 272, 2591–2601) and Css2 (this work). Each evolved variant showed strong cross-reactivity against several toxins, and was capable of neutralizing Cn2 and Css2. Furthermore, each variant neutralized the whole venoms of the above species. As far as we know, this is the first report of antibodies with such characteristics. Maturation processes revealed key residue changes to attain expression, stability, and affinity improvements as compared with the parental scFv. Combination of these changes resulted in the scFv LR, which is capable of rescuing mice from severe envenomation by 3 LD50 of freshly prepared whole venom of C. noxius (7.5 μg/20 g of mouse) and C. suffusus (26.25 μg/20 g of mouse), with surviving rates between 90 and 100%. Our research is leading to the formulation of an antivenom consisting of a discrete number of human scFvs endowed with strong cross-reactivity and low immunogenicity. PMID:21156801

  13. An optimized assay of specific IgE antibodies to reactive dyes and studies of immunologic responses in exposed workers.

    Science.gov (United States)

    Wass, U; Nilsson, R; Nordlinder, R; Belin, L

    1990-03-01

    Methods of assaying reactive dye-specific IgE antibodies were investigated with a RAST. Sera from three patients, occupationally exposed to a reactive dye, Remazol black B (Chemical Abstract registry number 17095-24-8), were used. Directly dyed disks, that is, disks without any carrier protein, resulted in poor and unreliable measures of specific IgE. In contrast, optimized preparation of conjugates between the dye and human serum albumin resulted in efficient binding of specific IgE. The patients' RAST results were strongly positive, whereas sera from 36 exposed workers but without symptoms and sera from unexposed subjects with high levels of total IgE were negative. The hapten and carrier specificity of the IgE antibodies was studied by direct RAST and RAST inhibition. In one patient, the antibodies were principally hapten specific, whereas another patient was found to have antibodies with a high degree of specificity to the carrier. The third patient's antibodies were intermediate between the other two patients' antibodies in this respect, suggesting that antibody specificity is dependent not only on the nature of the hapten but also on individual immune response factors. The study demonstrates that it is important to use an optimized preparation of dye-protein conjugates to elicit reliable results and a high degree of specific IgE binding in the RAST.

  14. Elucidation of the potential disease-promoting influence of IgM apoptotic cell-reactive antibodies in lupus.

    Science.gov (United States)

    Malik, M; Arora, P; Sachdeva, R; Sharma, L; Ramachandran, V G; Pal, R

    2016-06-01

    The undigested remnants of apoptosis are believed to stimulate the generation of autoantibodies in lupus. The biological properties of initiator, disease-specific IgM antibodies that specifically recognize apoptotic cells, readily detected in the sera of lupus patients, remain unclear. Apoptotic cell-reactive IgM monoclonal antibodies (generated from lupus-prone mice), as opposed to control IgM, preferentially stimulated maturation of bone marrow-derived dendritic cells (BMDCs) derived from such mice, relative to BMDCs derived from healthy mice. An influence of both antibody specificity and cell genotype was also apparent in the secretion of signature inflammatory cytokines. Immunization of such antibodies in lupus-prone animals induced increases in total serum IgG levels, with the elicited antibodies also preferentially recognizing moieties on dying cells. An expanded specificity was apparent both upon Western blot on cellular lysate and from the enhanced recognition of dsDNA, Ro60, RNP68 and Sm; the antibody most efficient in mediating autoreactive diversity, while being germline encoded, also induced the highest degree of phenotypic changes on BMDCs. Apoptotic cell-reactive IgM antibodies may therefore be potentially capable of influencing the course of systemic autoimmune disease by affecting both innate and adaptive immunity.

  15. Potential cross-reactivity of monoclonal antibodies against clinically relevant mycobacteria.

    Science.gov (United States)

    Flores-Moreno, K; Celis-Meneses, J S; Meneses-Ruiz, D M; Castillo-Rodal, A I; Orduña, P; Montiel, B A; López-Vidal, Y

    2014-08-01

    Tuberculosis is a disease caused by the Mycobacterium tuberculosis complex (MTb). In 2011, global mortality due to tuberculosis was 1·4 million individuals. The only available vaccine is the attenuated M. bovis [bacillus Calmette-Guérin (BCG)] strain, which confers variable protection against pulmonary tuberculosis. Some widely distributed non-tuberculous mycobacteria (NTM), such as M. avium and M. arupense, are also potential pathogens for humans. This work aimed to produce and characterize monoclonal antibodies against the M. bovis BCG Mexico strain of the MTb, M. avium subs. hominissuis and the M. arupense strain from NTM. Hybridomas were produced from splenocytes of BALB/c female mice immunized with radiation-inactivated mycobacteria, and the immunoglobulin (Ig)G2a antibody-producing clones with the highest antigenic recognition were selected. The selected clones, Mbv 2A10 for M. bovis BCG Mexico, Mav 3H1 for M. avium and Mar 2D10 for M. arupense, were used in further studies. Enzyme-linked immunosorbent assay (ELISA) and immune proteomics analyses characterized the clones as having the highest cross-reactivity with mycobacteria. Using mass spectrometry, a number of proteins recognized by the monoclonal antibody (mAb) clones were identified. These proteins had roles in metabolic processes, hypoxia, cell cycle and dormancy. In addition, a Clustal W and Immune Epitope Database (IEDB) in-silico analysis was performed in protein sequences that result in the conserved regions within probability epitopes that could be recognized for Mbv2A10 and Mav3H1 clones.

  16. Reactivity of alveolar epithelial cells in primary culture with type I cell monoclonal antibodies.

    Science.gov (United States)

    Danto, S I; Zabski, S M; Crandall, E D

    1992-03-01

    An understanding of the process of alveolar epithelial cell growth and differentiation requires the ability to trace and analyze the phenotypic transitions that the cells undergo. This analysis demands specific phenotypic probes to type II and, especially, type I pneumocytes. To this end, monoclonal antibodies have been generated to type I alveolar epithelial cells using an approach designed to enhance production of lung-specific clones from a crude lung membrane preparation. The monoclonal antibodies were screened by a combination of enzyme-linked immunosorbent assay and immunohistochemical techniques, with the determination of type I cell specificity resting primarily on immunoelectron microscopic localization. Two of these new markers of the type I pneumocyte phenotype (II F1 and VIII B2) were used to analyze primary cultures of type II cells growing on standard tissue culture plastic and on a variety of substrata reported to affect the morphology of these cells in culture. On tissue culture plastic, the antibodies fail to react with early (days 1 to 3) type II cell cultures. The cells become progressively more reactive with time in culture to a plateau of approximately 6 times background by day 8, with a maximum rate of increase between days 3 and 5. This finding is consistent with the hypothesis that type II cells in primary culture undergo at least partial differentiation into type I cells. Type II cells grown on laminin, which reportedly delays the loss of type II cell appearance, and on fibronectin, which has been reported to facilitate cell spreading and loss of type II cell features, develop the type I cell markers during cultivation in vitro with kinetics similar to those on uncoated tissue culture plastic. Cells on type I collagen and on tissue culture-treated Nuclepore filters, which have been reported to support monolayers with type I cell-like morphology, also increase their expression of the II F1 and VIII B2 epitopes around days 3 to 5. Taken

  17. Cross-reactivities of mammalian MAPKs antibodies in rotifer and copepod: Application in mechanistic studies in aquatic ecotoxicology.

    Science.gov (United States)

    Kang, Hye-Min; Jeong, Chang-Bum; Lee, Young Hwan; Cui, Yan-Hong; Kim, Duck-Hyun; Lee, Min-Chul; Kim, Hui-Su; Han, Jeonghoon; Hwang, Dae-Sik; Lee, Su-Jae; Lee, Jae-Seong

    2016-12-21

    The mitogen-activated protein kinases (MAPKs) family is known to mediate various biological processes in response to diverse environmental pollutants. Although MAPKs are well characterized and studied in vertebrates, in invertebrates the cross-reactivities of MAPKs antibodies were not clearly known in response to environmental pollutants due to limited information of antibody epitopes with material resources for invertebrates. In this paper, we performed phylogenetic analysis of MAPKs genes in the marine rotifer Brachionus koreanus and the copepods Paracyclopina nana and Tigriopus japonicus. Also in rotifer and copepods, several studies of Western blot of MAPK signaling pathways were shown in response to environmental pollutants, including multi-walled carbon nanotubes (MWCNTs), water-accommodated fractions (WAFs) of crude oil, and microplastics. This paper will provide a better understanding of the underlying mechanistic scenario in terms of cross-reactivities of mammalian antibodies in rotifer and copepod. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Dengue viruses are enhanced by distinct populations of serotype cross-reactive antibodies in human immune sera.

    Directory of Open Access Journals (Sweden)

    Ruklanthi de Alwis

    2014-10-01

    Full Text Available Dengue viruses (DENV are mosquito-borne flaviviruses of global importance. DENV exist as four serotypes, DENV1-DENV4. Following a primary infection, individuals produce DENV-specific antibodies that bind only to the serotype of infection and other antibodies that cross-react with two or more serotypes. People exposed to a secondary DENV infection with another serotype are at greater risk of developing more severe forms of dengue disease. The increased risk of severe dengue in people experiencing repeat DENV infections appear to be due, at least in part, to the ability of pre-existing serotype cross-reactive antibodies to form virus-antibody complexes that can productively infect Fcγ receptor-bearing target cells. While the theory of antibody-dependent enhancement (ADE is supported by several human and small animal model studies, the specific viral antigens and epitopes recognized by enhancing human antibodies after natural infections have not been fully defined. We used antibody-depletion techniques to remove DENV-specific antibody sub-populations from primary DENV-immune human sera. The effects of removing specific antibody populations on ADE were tested both in vitro using K562 cells and in vivo using the AG129 mouse model. Removal of serotype cross-reactive antibodies ablated enhancement of heterotypic virus infection in vitro and antibody-enhanced mortality in vivo. Further depletion studies using recombinant viral antigens showed that although the removal of DENV E-specific antibodies using recombinant E (rE protein resulted in a partial reduction in DENV enhancement, there was a significant residual enhancement remaining. Competition ADE studies using prM-specific Fab fragments in human immune sera showed that both rE-specific and prM-specific antibodies in primary DENV-immune sera significantly contribute to enhancement of heterotypic DENV infection in vitro. Identification of the targets of DENV-enhancing antibodies should contribute to

  19. Assessing drivers of the IgG4 antibody reactivity to recombinant antigen Bm14 in Wuchereria bancrofti endemic populations in East Africa

    DEFF Research Database (Denmark)

    Hansen, Johanne Damgaard; Meyrowitsch, Dan W.; Rwegoshora, Rwehumbiza T.;

    2016-01-01

    ). The antibodies are commonly regarded as markers of infection and/or exposure to filarial larvae, but a direct association between the antibodies and these indices has not been well documented. The present study assessed the role and relative effect of potential drivers of the human IgG4 antibody reactivity...... antibodies had been induced but where CFA was not (yet?) measurable. Although the study indicated that IgG4 reactivity to Bm14 is a marker of filarial infection, assessment of this reactivity, especially in children, will still be useful for indirect monitoring of changes in transmission intensity, including...

  20. Minimizing antibody cross-reactivity in multiplex detection of biomarkers in paper-based point-of-care assays

    Science.gov (United States)

    Dias, J. T.; Lama, L.; Gantelius, J.; Andersson-Svahn, H.

    2016-04-01

    Highly multiplexed immunoassays could allow convenient screening of hundreds or thousands of protein biomarkers simultaneously in a clinical sample such as serum or plasma, potentially allowing improved diagnostic accuracy and clinical management of many conditions such as autoimmune disorders, infections, and several cancers. Currently, antibody microarray-based tests are limited in part due to cross reactivity from detection antibody reagents. Here we present a strategy that reduces the cross-reactivity between nanoparticle-bound reporter antibodies through the application of ultrasound energy. By this concept, it was possible to achieve a sensitivity 103-fold (5 pg mL-1) lower than when no ultrasound was applied (50 ng mL-1) for the simultaneous detection of three different antigens. The detection limits and variability achieved with this technique rival those obtained with other types of multiplex sandwich assays.Highly multiplexed immunoassays could allow convenient screening of hundreds or thousands of protein biomarkers simultaneously in a clinical sample such as serum or plasma, potentially allowing improved diagnostic accuracy and clinical management of many conditions such as autoimmune disorders, infections, and several cancers. Currently, antibody microarray-based tests are limited in part due to cross reactivity from detection antibody reagents. Here we present a strategy that reduces the cross-reactivity between nanoparticle-bound reporter antibodies through the application of ultrasound energy. By this concept, it was possible to achieve a sensitivity 103-fold (5 pg mL-1) lower than when no ultrasound was applied (50 ng mL-1) for the simultaneous detection of three different antigens. The detection limits and variability achieved with this technique rival those obtained with other types of multiplex sandwich assays. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr09207h

  1. Immunization of rabbits with nematode Ascaris lumbricoides antigens induces antibodies cross-reactive to house dust mite Dermatophagoides farinae antigens.

    Science.gov (United States)

    Nakazawa, Takuya; Khan, Al Fazal; Yasueda, Hiroshi; Saito, Akemi; Fukutomi, Yuma; Takai, Toshiro; Zaman, Khalequz; Yunus, Md; Takeuchi, Haruko; Iwata, Tsutomu; Akiyama, Kazuo

    2013-01-01

    There are controversial reports on the relationship between helminthic infection and allergic diseases. Although IgE cross-reactivity between nematode Ascaris antigens and house dust-mite allergens in allergic patients have been reported, whether Ascaris or the mite is the primary sensitizer remains unknown. Here we found that immunization of naïve animals with Ascaris lumbricoides (Al) antigens induced production of antibodies cross-reactive to mite antigens from Dermatophagoides farinae (Df). Sera from Bangladeshi children showed IgE reactivity to Ascaris and mite extracts. IgG from rabbits immunized with Al extract exhibited reactivity to Df antigens. Treatment of the anti-Al antibody with Df antigen-coupled beads eliminated the reactivity to Df antigens. In immunoblot analysis, an approximately 100-kDa Df band was the most reactive to anti-Al IgG. The present study is the first step towards the establishment of animal models to study the relationship between Ascaris infection and mite-induced allergic diseases.

  2. HIV-1 VACCINES. Diversion of HIV-1 vaccine-induced immunity by gp41-microbiota cross-reactive antibodies.

    Science.gov (United States)

    Williams, Wilton B; Liao, Hua-Xin; Moody, M Anthony; Kepler, Thomas B; Alam, S Munir; Gao, Feng; Wiehe, Kevin; Trama, Ashley M; Jones, Kathryn; Zhang, Ruijun; Song, Hongshuo; Marshall, Dawn J; Whitesides, John F; Sawatzki, Kaitlin; Hua, Axin; Liu, Pinghuang; Tay, Matthew Z; Seaton, Kelly E; Shen, Xiaoying; Foulger, Andrew; Lloyd, Krissey E; Parks, Robert; Pollara, Justin; Ferrari, Guido; Yu, Jae-Sung; Vandergrift, Nathan; Montefiori, David C; Sobieszczyk, Magdalena E; Hammer, Scott; Karuna, Shelly; Gilbert, Peter; Grove, Doug; Grunenberg, Nicole; McElrath, M Juliana; Mascola, John R; Koup, Richard A; Corey, Lawrence; Nabel, Gary J; Morgan, Cecilia; Churchyard, Gavin; Maenza, Janine; Keefer, Michael; Graham, Barney S; Baden, Lindsey R; Tomaras, Georgia D; Haynes, Barton F

    2015-08-14

    An HIV-1 DNA prime vaccine, with a recombinant adenovirus type 5 (rAd5) boost, failed to protect from HIV-1 acquisition. We studied the nature of the vaccine-induced antibody (Ab) response to HIV-1 envelope (Env). HIV-1-reactive plasma Ab titers were higher to Env gp41 than to gp120, and repertoire analysis demonstrated that 93% of HIV-1-reactive Abs from memory B cells responded to Env gp41. Vaccine-induced gp41-reactive monoclonal antibodies were non-neutralizing and frequently polyreactive with host and environmental antigens, including intestinal microbiota (IM). Next-generation sequencing of an immunoglobulin heavy chain variable region repertoire before vaccination revealed an Env-IM cross-reactive Ab that was clonally related to a subsequent vaccine-induced gp41-reactive Ab. Thus, HIV-1 Env DNA-rAd5 vaccine induced a dominant IM-polyreactive, non-neutralizing gp41-reactive Ab repertoire response that was associated with no vaccine efficacy. Copyright © 2015, American Association for the Advancement of Science.

  3. Antibody reactivities to glutamate-rich peptides of Plasmodium falciparum parasites in humans from areas of different malaria endemicity

    DEFF Research Database (Denmark)

    Jakobsen, P H; Theander, T G; Hviid, L;

    1996-01-01

    in individuals from malaria-endemic areas of Sudan, Indonesia and The Gambia to study antibody responses to these peptides in donors living in areas of different malaria endemicity. IgG and IgM reactivities to the peptides increased with malaria endemicity, although there were no differences in reactivities...... to the GLURP peptide between non-exposed donors and donors living in areas of low malaria endemicity. IgG reactivities to the GLURP peptide in Sudanese adults were high one month after treatment in all adults tested, while IgG reactivities to the ABRA peptide were infrequent. IgM responses to the peptides...... in areas of low malaria endemicity....

  4. Is hepatitis C virus infection a risk factor for panel-reactive antibody positivity?

    Science.gov (United States)

    Ozdemir, F N; Sezer, S; Güz, G; Arat, Z; Turan, M; Haberal, M

    2000-01-01

    Patients with high levels of panel-reactive antibody (PRA) represent an increasingly large group in the waiting lists for cadaveric renal transplantation. Hepatitis C virus (HCV) infection has been found to be associated with a high prevalence of positivity of autoimmune serological tests. We planned this study to evaluate the effect of HCV positivity on the PRA levels in our hemodialysis (HD) patients. We included 38 HCV-infected (group I: 20 male, 18 female patients, mean duration of HD 73.6 +/- 50.6 months) and 43 hepatitis marker-negative (group II: 23 male, 20 female patients, mean duration of HD 22.2 +/- 22.4 months) HD patients. The PRA positivity ratio and number of transfusions were not significantly higher in group I than in group II (PRA ABC; 28.9%, 19.4, P > 0.05, PRA DR; 21.8%, 20.9, P > 0.05, respectively, and blood transfusions 7.0 +/- 5.7, 6.6 +/- 5.2, respectively, P = 0.06). HD duration correlated significantly with PRA positivity in our patients (PRA-positive patients: 56.1 +/- 57.9 months, PRA-negative patients: 43.3 +/- 41.9 months, P = 0.021). In conclusion, HD duration was found to be the main factor affecting PRA sensitivity independently of HCV positivity and blood transfusion.

  5. Guillain-Barre syndrome-related Campylobacter jejuni in Bangladesh: ganglioside mimicry and cross-reactive antibodies.

    Directory of Open Access Journals (Sweden)

    Zhahirul Islam

    Full Text Available BACKGROUND: Campylobacter jejuni is the predominant antecedent infection in Guillain-Barré syndrome (GBS. Molecular mimicry and cross-reactive immune responses to C. jejuni lipo-oligosaccharides (LOS precipitate the development of GBS, although this mechanism has not been established in patients from developing countries. We determined the carbohydrate mimicry between C. jejuni LOS and gangliosides, and the cross-reactive antibody response in patients with GBS in Bangladesh. METHODOLOGY: Sera from 97 GBS patients, and 120 neurological and family controls were tested for antibody reactivity against LOS from C. jejuni isolates from GBS patients in Bangladesh (BD-07, BD-39, BD-10, BD-67 and BD-94 by enzyme-linked immunosorbent assay (ELISA. Cross-reactivity to LOS was determined by ELISA. The LOS outer core structures of C. jejuni strains associated with GBS/MFS were determined by mass spectrometry. PRINCIPLE FINDINGS: IgG antibodies to LOS from C. jejuni BD-07, BD-39, BD-10, and BD-67 IgG antibodies were found in serum from 56%, 58%, 14% and 15% of GBS patients respectively, as compared to very low frequency (<3% in controls (p<0.001. Monoclonal antibodies specific for GM1 and GD1a reacted strongly with LOS from the C. jejuni strains (BD-07 and BD-39. Mass spectrometry analysis confirmed the presence of GM1 and GD1a carbohydrate mimics in the LOS from C. jejuni BD-07 and BD-39. Both BD-10 and BD-67 express the same LOS outer core, which appears to be a novel structure displaying GA2 and GD3 mimicry. Up to 90-100% of serum reactivity to gangliosides in two patients (DK-07 and DK-39 was inhibited by 50 µg/ml of LOS from the autologous C. jejuni isolates. However, patient DK-07 developed an anti-GD1a immune response while patient DK-39 developed an anti-GM1 immune response. CONCLUSION: Carbohydrate mimicry between C. jejuni LOS and gangliosides, and cross-reactive serum antibody precipitate the majority of GBS cases in Bangladesh.

  6. Guillain-Barré syndrome-related Campylobacter jejuni in Bangladesh: ganglioside mimicry and cross-reactive antibodies.

    Science.gov (United States)

    Islam, Zhahirul; Gilbert, Michel; Mohammad, Quazi D; Klaij, Kevin; Li, Jianjun; van Rijs, Wouter; Tio-Gillen, Anne P; Talukder, Kaisar A; Willison, Hugh J; van Belkum, Alex; Endtz, Hubert P; Jacobs, Bart C

    2012-01-01

    Campylobacter jejuni is the predominant antecedent infection in Guillain-Barré syndrome (GBS). Molecular mimicry and cross-reactive immune responses to C. jejuni lipo-oligosaccharides (LOS) precipitate the development of GBS, although this mechanism has not been established in patients from developing countries. We determined the carbohydrate mimicry between C. jejuni LOS and gangliosides, and the cross-reactive antibody response in patients with GBS in Bangladesh. Sera from 97 GBS patients, and 120 neurological and family controls were tested for antibody reactivity against LOS from C. jejuni isolates from GBS patients in Bangladesh (BD-07, BD-39, BD-10, BD-67 and BD-94) by enzyme-linked immunosorbent assay (ELISA). Cross-reactivity to LOS was determined by ELISA. The LOS outer core structures of C. jejuni strains associated with GBS/MFS were determined by mass spectrometry. IgG antibodies to LOS from C. jejuni BD-07, BD-39, BD-10, and BD-67 IgG antibodies were found in serum from 56%, 58%, 14% and 15% of GBS patients respectively, as compared to very low frequency (<3%) in controls (p<0.001). Monoclonal antibodies specific for GM1 and GD1a reacted strongly with LOS from the C. jejuni strains (BD-07 and BD-39). Mass spectrometry analysis confirmed the presence of GM1 and GD1a carbohydrate mimics in the LOS from C. jejuni BD-07 and BD-39. Both BD-10 and BD-67 express the same LOS outer core, which appears to be a novel structure displaying GA2 and GD3 mimicry. Up to 90-100% of serum reactivity to gangliosides in two patients (DK-07 and DK-39) was inhibited by 50 µg/ml of LOS from the autologous C. jejuni isolates. However, patient DK-07 developed an anti-GD1a immune response while patient DK-39 developed an anti-GM1 immune response. Carbohydrate mimicry between C. jejuni LOS and gangliosides, and cross-reactive serum antibody precipitate the majority of GBS cases in Bangladesh.

  7. Flow Cytometric Panel-Reactive Antibody Results and the Ability to Find Transfusion-Compatible Platelets after Antibody-Desensitization for Allogeneic Bone Marrow Transplant.

    Science.gov (United States)

    Rosenbaum, Eric R; Pandey, Soumya; Harville, Terry O; Drobena, Gina A; Cottler-Fox, Michele

    2016-12-01

    Panel reactive antibody (PRA) reduction protocols are used to decrease anti-HLA antibodies with concomitant PRA monitoring as a measure of successful treatment prior to organ and haploidentical blood and marrow transplant (BMT). We hypothesized that the more sensitive flow cytometry (FC) based assays for PRA [FlowPRA(®) and Luminex(®) based Single Antigen Bead (SAB)] would also correlate with the ability to find compatible platelets for allosensitized recipients. A female patient with myelodysplastic syndrome and a high HLA class I PRA [>90% PRA and cPRA by complement-dependent cytotoxicity (CDC) assay and Flow PRA] required allogeneic BMT. Baseline HLA Class I and class II antigen typing was performed and a matched sibling donor was identified. Although baseline anti-HLA class I and class II antibodies measured by FC and CDC revealed no donor specific antibodies (DSA), the decision was made to attempt antibody desensitization to facilitate platelet transfusion during BMT. FC and CDC assays were performed to determine anti-HLA class I antibodies and cPRA/%PRA prior to starting desensitization and at the end of desensitization. Over the course of desensitization and BMT, a total of 194 apheresis platelet units underwent cross-match (XM) using Capture-P(®). We compared temporally-related PRA results with platelet XM results. High PRA by FC or CDC assays correlates with a high % of XM-positive (incompatible) platelet units. When the CDC PRA fell to 2% after desensitization, platelet XM incompatibility fell from 100% to 63% positive (incompatible). When the FC PRA fell to 5% the positive platelet XM fell to 5%. Antibody desensitization facilitated platelet transfusion. PRA determination by FC appeared better correlated than determination by CDC with the ability to find XM-compatible platelets. © 2016 by the Association of Clinical Scientists, Inc.

  8. Simulation of B Cell Affinity Maturation Explains Enhanced Antibody Cross-Reactivity Induced by the Polyvalent Malaria Vaccine AMA1

    Science.gov (United States)

    2014-07-01

    other Ags this may not be the case. For example, in dengue virus, subneutralizing cross-reactive Abs and cross- reactive memory B cells are thought to...HLA-driven CD8 + T- cell escape mutations and covarying HLA-independent polymorphisms. J. Virol. 85: 1384–1390. 33. Fischer, W., V. V. Ganusov, E. E...Y. Lee, K. L. Artiles, S. Zompi, M. J. Vargas, B. B. Simen, et al. 2013. Convergent antibody signatures in human dengue . Cell Host Microbe 13: 691–700

  9. Complement-Dependent Lysis of Influenza A Virus-Infected Cells by Broadly Cross-Reactive Human Monoclonal Antibodies

    Science.gov (United States)

    Terajima, Masanori; Cruz, John; Co, Mary Dawn T.; Lee, Jane-Hwei; Kaur, Kaval; Wilson, Patrick C.; Ennis, Francis A.

    2011-01-01

    We characterized human monoclonal antibodies (MAbs) cloned from influenza virus-infected patients and from influenza vaccine recipients by complement-dependent lysis (CDL) assay. Most MAbs active in CDL were neutralizing, but not all neutralizing MAbs can mediate CDL. Two of the three stalk-specific neutralizing MAbs tested were able to mediate CDL and were more cross-reactive to temporally distant H1N1 strains than the conventional hemagglutination-inhibiting and neutralizing MAbs. One of the stalk-specific MAbs was subtype cross-reactive to H1 and H2 hemagglutinins, suggesting a role for stalk-specific antibodies in protection against influenza illness, especially by a novel viral subtype which can cause pandemics. PMID:21994454

  10. Analysis of two monoclonal antibodies reactive with envelope proteins of murine retroviruses: one pan specific antibody and one specific for Moloney leukemia virus.

    Science.gov (United States)

    Evans, Leonard H; Boi, Stefano; Malik, Frank; Wehrly, Kathy; Peterson, Karin E; Chesebro, Bruce

    2014-05-01

    Many monoclonal antibodies (MAbs) reactive with various proteins of murine leukemia viruses (MuLVs) have been developed. In this report two additional MAbs with differing and unusual specificities are described. MAb 573 is reactive with the envelope protein of all MuLVs tested including viruses in the ecotropic, xenotropic, polytropic and amphotropic classes. Notably, MAb 573 is one of only two reported MAbs that react with the envelope protein of amphotropic MuLVs. This MAb appears to recognize a conformational epitope within the envelope protein, as it reacts strongly with live virus and live infected cells, but does not react with formalin-fixed or alcohol-fixed infected cells or denatured viral envelope protein in immunoblots. In contrast, Mab 538 reacts only with an epitope unique to the envelope protein of the Moloney (Mo-) strain of MuLV, a prototypic ecotropic MuLV that is the basis for many retroviral tools used in molecular biology. MAb 538 can react with live cells and viruses, or detergent denatured or fixed envelope protein. The derivation of these antibodies as well as their characterization with regard to their isotype, range of reactivity with different MuLVs and utility in different immunological procedures are described in this study.

  11. Production of Mouse Monoclonal Antibody against Morphine without Cross Reactivity with Heroin

    Directory of Open Access Journals (Sweden)

    S Kashaninan

    2014-12-01

    Conclusion: The study findings revealed that the produced antibody against morphine was comparable with other antibodies for specificity and affinity; therefore it is usable in design of diagnostic immunoassay in biologic fluids.

  12. Specific Antibodies for the Detection of Alternaria Allergens and the Identification of Cross-Reactive Antigens in Other Fungi

    Science.gov (United States)

    Twaroch, Teresa E.; Curin, Mirela; Sterflinger, Katja; Focke-Tejkl, Margit; Swoboda, Ines; Valenta, Rudolf

    2017-01-01

    Background The mould Alternaria alternata is an important source of respiratory allergens. A. alternata extracts show great variations regarding allergenic potency. The aim of this study was to generate antibody probes specific for important Alternaria allergens and to use them to study allergen expression, depending on different culture conditions, as well as to search for cross-reactive allergens in other mould species. Methods Synthetic peptides from antigenic regions of A. alternata allergens (Alt a 1, Alt a 2, Alt a 3, Alt a 6 and Alt a 8) were used to raise highly specific rabbit antibodies. These antibodies and IgE from allergic patients were used to detect allergens by immunoblotting in extracts of 4 A. alternata strains grown under varying culturing conditions, in commercial skin-prick extracts and in closely (Cladosporium herbarum and Aureobasidium pullulans) or distantly related (Aspergillus niger and Penicillium chrysogenum) mould species. Results There was a wide variation of expression of the individual A. Alternata allergens, depending on the strain and culture conditions, but the antibody probes allowed us to distinguish strains and culture conditions with low and high allergen expression. In the commercial skin-prick solutions, varying levels of Alt a 1 were found, but no other allergens were detectable. Alt a 1 was identified as species-specific A. Alternata allergen, whereas Alt a 3, 6- and Alt a 8-cross-reactive antigens were found in C. herbarum and/or A. pullulans. Conclusions and Clinical Relevance Peptide-specific antibodies are useful to analyze diagnostic and therapeutic mould extracts, to study the presence of A. Alternata allergens in biological samples and to search for cross-reactive allergens in other mould species. PMID:27780168

  13. Study of a Cohort of 1,886 Persons To Determine Changes in Antibody Reactivity to Borrelia burgdorferi 3 Months after a Tick Bite

    DEFF Research Database (Denmark)

    Dessau, Ram B; Fryland, Linda; Wilhelmsson, Peter

    2015-01-01

    Lyme borreliosis is a tick-borne disease caused by the bacterium Borrelia burgdorferi. The most frequent clinical manifestation is a rash called erythema migrans. Changes in antibody reactivity to B. burgdorferi 3 months after a tick bite are measured using enzyme-linked immunosorbent assays...... antigen and the C6 antigen, respectively. Graphical methods to display the antibody response and to choose thresholds for a rise in relative antibody reactivity are shown and discussed. In conclusion, 5.4% of people with tick bites showed a rise in Borrelia-specific antibodies above the 2.5% threshold...

  14. Antibody

    Science.gov (United States)

    An antibody is a protein produced by the body's immune system when it detects harmful substances, called antigens. Examples ... microorganisms (bacteria, fungi, parasites, and viruses) and chemicals. Antibodies may be produced when the immune system mistakenly ...

  15. Cross-reactive anti-PfCLAG9 antibodies in the sera of asymptomatic parasite carriers of Plasmodium vivax

    Science.gov (United States)

    Costa, Joana D'Arc Neves; Zanchi, Fernando Berton; Rodrigues, Francisco Lurdevanhe da Silva; Honda, Eduardo Rezende; Katsuragawa, Tony Hiroschi; Pereira, Dhélio Batista; Taborda, Roger Lafontaine Mesquita; Tada, Mauro Shugiro; Ferreira, Ricardo de Godoi Mattos; Pereira-da-Silva, Luiz Hildebrando

    2013-01-01

    The PfCLAG9 has been extensively studied because their immunogenicity. Thereby, the gene product is important for therapeutics interventions and a potential vaccine candidate. Antibodies against synthetic peptides corresponding to selected sequences of the Plasmodium falciparum antigen PfCLAG9 were found in sera of falciparum malaria patients from Rondônia, in the Brazilian Amazon. Much higher antibody titres were found in semi-immune and immune asymptomatic parasite carriers than in subjects suffering clinical infections, corroborating original findings in Papua Guinea. However, sera of Plasmodium vivax patients from the same Amazon area, in particular from asymptomatic vivax parasite carriers, reacted strongly with the same peptides. Bioinformatic analyses revealed regions of similarity between P. falciparum Pfclag9 and the P. vivax ortholog Pvclag7. Indirect fluorescent microscopy analysis showed that antibodies against PfCLAG9 peptides elicited in BALB/c mice react with human red blood cells (RBCs) infected with both P. falciparum and P. vivax parasites. The patterns of reactivity on the surface of the parasitised RBCs are very similar. The present observations support previous findings that PfCLAG9 may be a target of protective immune responses and raises the possibility that the cross reactive antibodies to PvCLAG7 in mixed infections play a role in regulate the fate of Plasmodium mixed infections. PMID:23440122

  16. Cross-reactive anti-PfCLAG9 antibodies in the sera of asymptomatic parasite carriers of Plasmodium vivax

    Directory of Open Access Journals (Sweden)

    Joana D'Arc Neves Costa

    2013-02-01

    Full Text Available The PfCLAG9 has been extensively studied because their immunogenicity. Thereby, the gene product is important for therapeutics interventions and a potential vaccine candidate. Antibodies against synthetic peptides corresponding to selected sequences of the Plasmodium falciparum antigen PfCLAG9 were found in sera of falciparum malaria patients from Rondônia, in the Brazilian Amazon. Much higher antibody titres were found in semi-immune and immune asymptomatic parasite carriers than in subjects suffering clinical infections, corroborating original findings in Papua Guinea. However, sera of Plasmodium vivax patients from the same Amazon area, in particular from asymptomatic vivax parasite carriers, reacted strongly with the same peptides. Bioinformatic analyses revealed regions of similarity between P. falciparum Pfclag9 and the P. vivax ortholog Pvclag7. Indirect fluorescent microscopy analysis showed that antibodies against PfCLAG9 peptides elicited in BALB/c mice react with human red blood cells (RBCs infected with both P. falciparum and P. vivax parasites. The patterns of reactivity on the surface of the parasitised RBCs are very similar. The present observations support previous findings that PfCLAG9 may be a target of protective immune responses and raises the possibility that the cross reactive antibodies to PvCLAG7 in mixed infections play a role in regulate the fate of Plasmodium mixed infections.

  17. Spatiotemporal Expression Patterns and Antibody Reactivity of Taeniidae Endophilin B1.

    Science.gov (United States)

    Ahn, Chun-Seob; Bae, Young-An; Kim, Seon-Hee; Kim, Jeong-Geun; Yu, Jae-Ran; Yang, Hyun-Jong; Eom, Keeseon S; Wang, Hu; Kang, Insug; Yang, Yichao; Kong, Yoon

    2016-10-01

    Larval Taeniidae, such as metacestodes of Taenia solium, Echinococcus granulosus, and Echinococcus multilocularis, produce chronic and fatal helminthic diseases. Proper identification of these zoonotic cestodiases is often challenging and is hampered in some clinical settings. Endophilin B1 plays critical roles in the maintenance of membrane contours and endocytosis. We isolated proteins homologous to endophilin B1 from T. solium, Taenia saginata, and Taenia asiatica The three Taeniidae endophilin B1 proteins shared 92.9 to 96.6% sequence identity. They harbored a Bin1/amphiphysin/Rvs (BAR) domain and residues for a dimeric interface but lacked a SRC homology 3 (SH3) domain. Endophilin B1 showed a unique immunological profile and was abundantly expressed in the tegumental syncytium of Taeniidae metacestodes and adults. Bacterially expressed recombinant T. solium endophilin B1 (rTsMEndoB1) demonstrated a sensitivity of 79.7% (345/433 cases) for serodiagnosis of larval Taeniidae infections. The protein showed strong immune recognition patterns against sera from patients with chronic neurocysticercosis, cystic echinococcosis, or advanced-stage alveolar echinococcosis. Adult Taeniidae infections exhibited moderate degrees of positive antibody responses (65.7% [23/35 samples]). rTsMEndoB1 showed some cross-reactivity with sera from patients infected with Diphyllobothriidae (23.6% [25/106 samples]) but not with sera from patients with other parasitic diseases or normal controls. The specificity was 91.7% (256/301 samples). The positive and negative predictive values were 93.6% and 73.4%, respectively. Our results demonstrate that Taeniidae endophilin B1 may be involved in the control of membrane dynamics, thus contributing to shaping and maintaining the tegumental curvature. rTsMEndoB1 may be useful for large-scale screening, as well as for individual diagnosis and follow-up surveillance of Taeniidae infections.

  18. Electrophile-modified lipoic derivatives of PDC-E2 elicits anti-mitochondrial antibody reactivity.

    Science.gov (United States)

    Naiyanetr, Phornnop; Butler, Jeffrey D; Meng, Liping; Pfeiff, Janice; Kenny, Thomas P; Guggenheim, Kathryn G; Reiger, Roman; Lam, Kit; Kurth, Mark J; Ansari, Aftab A; Coppel, Ross L; López-Hoyos, Marcos; Gershwin, M Eric; Leung, Patrick S C

    2011-11-01

    Our laboratory has hypothesized that xenobiotic modification of the native lipoyl moiety of the major mitochondrial autoantigen, the E2 subunit of the pyruvate dehydrogenase complex (PDC-E2), may lead to loss of self-tolerance in primary biliary cirrhosis (PBC). This thesis is based on the finding of readily detectable levels of immunoreactivity of PBC sera against extensive panels of protein microarrays containing mimics of the inner lipoyl domain of PDC-E2 and subsequent quantitative structure-activity relationships (QSARs). Importantly, we have demonstrated that murine immunization with one such mimic, 2-octynoic acid coupled to bovine serum albumin (BSA), induces anti-mitochondrial antibodies (AMAs) and cholangitis. Based upon these data, we have focused on covalent modifications of the lipoic acid disulfide ring and subsequent analysis of such xenobiotics coupled to a 15mer of PDC-E2 for immunoreactivity against a broad panel of sera from patients with PBC and controls. Our results demonstrate that AMA-positive PBC sera demonstrate marked reactivity against 6,8-bis(acetylthio)octanoic acid, implying that chemical modification of the lipoyl ring, i.e. disruption of the S-S disulfide, renders lipoic acid to its reduced form that will promote xenobiotic modification. This observation is particularly significant in light of the function of the lipoyl moiety in electron transport of which the catalytic disulfide constantly opens and closes and, thus, raises the intriguing thesis that common electrophilic agents, i.e. acetaminophen or non-steroidal anti-inflammatory drugs (NSAIDs), may lead to xenobiotic modification in genetically susceptible individuals that results in the generation of AMAs and ultimately clinical PBC.

  19. A conserved multi-gene family induces cross-reactive antibodies effective in defense against Plasmodium falciparum.

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    Subhash Singh

    Full Text Available BACKGROUND: Two related merozoite surface proteins, MSP3 and MSP6, have previously been identified as targets of antibody-dependent cellular inhibition (ADCI, a protective mechanism against Plasmodium falciparum malaria. Both MSP3 and MSP6 share a common characteristic small N-terminal signature amino-acid stretch (NLRNA/G, a feature similar to MSP3-like orthologs identified in other human and primate malaria parasites. METHODS/RESULTS: This signature amino-acid sequence led to the identification of eight ORFs contiguously located on P. falciparum chromosome 10. Our subsequent investigations on their expression, localization, sequence conservation, epitope sharing, immunogenicity and the functional role of antibodies in defense are reported here. Six members of P. falciparum MSP3-multigene family share similar sequence organization within their C-terminal regions, are simultaneously expressed as merozoite surface proteins and are highly conserved among parasite isolates. Each of these proteins is a target of naturally occurring antibodies effective at parasite killing in ADCI assays. Moreover, both naturally occurring antibodies and those generated by immunization display cross-reactivity with other members of the family and exhibit varied binding avidities. CONCLUSIONS/SIGNIFICANCE: The unusual characteristics of the MSP3 multi-gene family lead us to hypothesize that the simultaneous expression of targets eliciting cross-reactive antibody responses capable of controlling parasite densities could represent an immune process selected through evolution to maintain homeostasis between P. falciparum and human hosts; a process that allows the continuous transmission of the parasite without killing the host. Our observations also have practical consequences for vaccine development by suggesting MSP3 vaccine efficacy might be improved when combined with the various C-terminus regions of the MSP3 family members to generate a wider range of antibodies

  20. Study of Humoral Immunity to Commensal Oral Bacteria in Human Infants Demonstrates the Presence of Secretory Immunoglobulin A Antibodies Reactive with Actinomyces naeslundii Genospecies 1 and 2 Ribotypes

    Science.gov (United States)

    Cole, Michael F.; Evans, Mishell K.; Kirchherr, Jennifer L.; Sheridan, Michael J.; Bowden, G. H. W.

    2004-01-01

    The mouths of three human infants were examined from birth to age 2 years to detect colonization of Actinomyces naeslundii genospecies 1 and 2. These bacteria did not colonize until after tooth eruption. The diversity of posteruption isolates was determined by ribotyping. Using immunoblotting and enzyme-linked immunosorbent assay, we determined the reactivity of secretory immunoglobulin A (SIgA) antibodies in saliva samples collected from each infant before and after colonization against cell wall proteins from their own A. naeslundii strains and carbohydrates from standard A. naeslundii genospecies 1 and 2 strains. A. naeslundii genospecies 1 and 2 carbohydrate-reactive SIgA antibodies were not detected in any saliva sample. However, SIgA antibodies reactive with cell wall proteins were present in saliva before these bacteria colonized the mouth. These antibodies could be almost completely removed by absorption with A. odontolyticus, a species known to colonize the human mouth shortly after birth. However, after colonization by A. naeslundii genospecies 1 and 2, specific antibodies were induced that could not be removed by absorption with A. odontolyticus. Cluster analysis of the patterns of reactivity of postcolonization salivary antibodies from each infant with antigens from their own strains showed that not only could these antibodies discriminate among strains but antibodies in saliva samples collected at different times showed different reactivity patterns. Overall, these data suggest that, although much of the salivary SIgA antibodies reactive with A. naeslundii genospecies 1 and 2 are directed against genus-specific or more broadly cross-reactive antigens, species, genospecies, and possibly strain-specific antibodies are induced in response to colonization. PMID:15138172

  1. Reactivity of microhemagglutination, fluorescent treponemal antibody absorption, Venereal Disease Research Laboratory, and rapid plasma reagin tests in primary syphilis.

    Science.gov (United States)

    Huber, T W; Storms, S; Young, P; Phillips, L E; Rogers, T E; Moore, D G; Williams, R P

    1983-03-01

    Seroreactivity of sera from 109 patients with first-infection primary syphilis was 98.2% in the fluorescent treponemal antibody absorption test, 92.7% in the rapid plasma reagin 18-mm circle card test, 72.5% in the microhemagglutination test (MHA-TP), and 72.5% in the Venereal Disease Research Laboratory test. Seroreactivity of sera from 18 patients with primary syphilis with documented previous infection(s) was 100% in the fluorescent treponemal antibody absorption test, the rapid plasma reagin 18-mm circle card test, and the MHA-TP test and 88.9% in the Venereal Disease Research Laboratory test. The MHA-TP test failed to confirm reactivity in 13 of 79 sera which were reactive in the Venereal Disease Research Laboratory test and in 24 of 101 sera which were reactive in the rapid plasma reagin 18-mm circle card test. Testing another production lot of MHA-TP reagents resulted in even poorer correlation. The reactivity of the MHA-TP test in primary syphilis appeared to vary with the sensitivity of the production lot of reagents.

  2. Detection of Antibodies Reactive with Ehrlichia canis in a Kennel in Bulgaria

    OpenAIRE

    Tsachev, Ilia

    2006-01-01

    A seroepidemiological study on Ehrlichia canis infection was performed in 16 dogs in a kennel in the region of Plovdiv in Bulgaria. For this purpose, anti-E. canis antibodies were detected by the indirect immunofluorescence antibody test. The results showed that 75% of the dogs examined were positive to E. canis. The antibody titres 1:100, 1:200 and 1:400 were detected.

  3. H3N2 influenza infection elicits more cross-reactive and less clonally expanded anti-hemagglutinin antibodies than influenza vaccination.

    Directory of Open Access Journals (Sweden)

    M Anthony Moody

    Full Text Available BACKGROUND: During the recent H1N1 influenza pandemic, excess morbidity and mortality was seen in young but not older adults suggesting that prior infection with influenza strains may have protected older subjects. In contrast, a history of recent seasonal trivalent vaccine in younger adults was not associated with protection. METHODS AND FINDINGS: To study hemagglutinin (HA antibody responses in influenza immunization and infection, we have studied the day 7 plasma cell repertoires of subjects immunized with seasonal trivalent inactivated influenza vaccine (TIV and compared them to the plasma cell repertoires of subjects experimentally infected (EI with influenza H3N2 A/Wisconsin/67/2005. The majority of circulating plasma cells after TIV produced influenza-specific antibodies, while most plasma cells after EI produced antibodies that did not react with influenza HA. While anti-HA antibodies from TIV subjects were primarily reactive with single or few HA strains, anti-HA antibodies from EI subjects were isolated that reacted with multiple HA strains. Plasma cell-derived anti-HA antibodies from TIV subjects showed more evidence of clonal expansion compared with antibodies from EI subjects. From an H3N2-infected subject, we isolated a 4-member clonal lineage of broadly cross-reactive antibodies that bound to multiple HA subtypes and neutralized both H1N1 and H3N2 viruses. This broad reactivity was not detected in post-infection plasma suggesting this broadly reactive clonal lineage was not immunodominant in this subject. CONCLUSION: The presence of broadly reactive subdominant antibody responses in some EI subjects suggests that improved vaccine designs that make broadly reactive antibody responses immunodominant could protect against novel influenza strains.

  4. Disassembly and reassembly of human papillomavirus virus-like particles produces more virion-like antibody reactivity

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    Zhao Qinjian

    2012-02-01

    Full Text Available Abstract Background Human papillomavirus (HPV vaccines based on major capsid protein L1 are licensed in over 100 countries to prevent HPV infections. The yeast-derived recombinant quadrivalent HPV L1 vaccine, GARDASIL(R, has played an important role in reducing cancer and genital warts since its introduction in 2006. The L1 proteins self-assemble into virus-like particles (VLPs. Results VLPs were subjected to post-purification disassembly and reassembly (D/R treatment during bioprocessing to improve VLP immunoreactivity and stability. The post-D/R HPV16 VLPs and their complex with H16.V5 neutralizing antibody Fab fragments were visualized by cryo electron microscopy, showing VLPs densely decorated with antibody. Along with structural improvements, post-D/R VLPs showed markedly higher antigenicity to conformational and neutralizing monoclonal antibodies (mAbs H16.V5, H16.E70 and H263.A2, whereas binding to mAbs recognizing linear epitopes (H16.J4, H16.O7, and H16.H5 was greatly reduced. Strikingly, post-D/R VLPs showed no detectable binding to H16.H5, indicating that the H16.H5 epitope is not accessible in fully assembled VLPs. An atomic homology model of the entire HPV16 VLP was generated based on previously determined high-resolution structures of bovine papillomavirus and HPV16 L1 pentameric capsomeres. Conclusions D/R treatment of HPV16 L1 VLPs produces more homogeneous VLPs with more virion-like antibody reactivity. These effects can be attributed to a combination of more complete and regular assembly of the VLPs, better folding of L1, reduced non-specific disulfide-mediated aggregation and increased stability of the VLPs. Markedly different antigenicity of HPV16 VLPs was observed upon D/R treatment with a panel of monoclonal antibodies targeting neutralization sensitive epitopes. Multiple epitope-specific assays with a panel of mAbs with different properties and epitopes are required to gain a better understanding of the immunochemical

  5. Identification and Characterization of a Broadly Cross-Reactive HIV-1 Human Monoclonal Antibody That Binds to Both gp120 and gp41

    NARCIS (Netherlands)

    Zhang, Mei-Yun; Yuan, Tingting; Li, Jingjing; Borges, Andrew Rosa; Watkins, Jennifer D.; Guenaga, Javier; Yang, Zheng; Wang, Yanping; Wilson, Richard; Li, Yuxing; Polonis, Victoria R.; Pincus, Seth H.; Ruprecht, Ruth M.; Dimitrov, Dimiter S.

    2012-01-01

    Identification of broadly cross-reactive HIV-1-neutralizing antibodies (bnAbs) may assist vaccine immunogen design. Here we report a novel human monoclonal antibody (mAb), designated m43, which co-targets the gp120 and gp41 subunits of the HIV-1 envelope glycoprotein (Env). M43 bound to recombinant

  6. Induction of antibodies reactive to cardiac myosin and development of heart alterations in cruzipain-immunized mice and their offspring.

    Science.gov (United States)

    Giordanengo, L; Maldonado, C; Rivarola, H W; Iosa, D; Girones, N; Fresno, M; Gea, S

    2000-11-01

    Human and murine infection with Trypanosoma cruzi parasite is usually accompanied by strong humoral and cellular immune response to cruzipain, a parasite immunodominant antigen. In the present study we report that the immunization of mice with cruzipain devoid of enzymatic activity, was able to induce antibodies which bind to a 223-kDa antigen from a mouse heart extract. We identified this protein as the mouse cardiac myosin heavy chain by sequencing analysis. The study of IgG isotype profile revealed the occurrence of all IgG isotypes against cruzipain and myosin. IgG1 showed the strongest reactivity against cruzipain, whereas IgG2a was the main isotype against myosin. Anti-cruzipain antibodies purified by immunoabsorption recognized the cardiac myosin heavy chain, suggesting cross-reactive epitopes between cruzipain and myosin. Autoimmune response in mice immunized with cruzipain was associated to heart conduction disturbances. In addition, ultrastructural findings revealed severe alterations of cardiomyocytes and IgG deposit on heart tissue of immunized mice. We investigated whether antibodies induced by cruzipain transferred from immunized mothers to their offsprings could alter the heart function in the pups. All IgG isotypes against cruzipain derived from transplacental crossing were detected in pups' sera. Electrocardiographic studies performed in the offsprings born to immunized mothers revealed conduction abnormalities. These results provide strong evidence for a pathogenic role of autoimmune response induced by a purified T. cruzi antigen in the development of experimental Chagas' disease.

  7. Cross-reactive neutralizing antibody responses to enterovirus 71 infections in young children: implications for vaccine development.

    Directory of Open Access Journals (Sweden)

    Mei-Liang Huang

    Full Text Available BACKGROUND: Recently, enterovirus 71 (EV71 has caused life-threatening outbreaks involving neurological and cardiopulmonary complications in Asian children with unknown mechanism. EV71 has one single serotype but can be phylogenetically classified into 3 main genogroups (A, B and C and 11 genotypes (A, B1∼B5 and C1∼C5. In Taiwan, nationwide EV71 epidemics with different predominant genotypes occurred in 1998 (C2, 2000-2001 (B4, 2004-2005 (C4, and 2008 (B5. In this study, sera were collected to measure cross-reactive neutralizing antibody titers against different genotypes. METHODS: We collected historical sera from children who developed an EV71 infection in 1998, 2000, 2005, 2008, or 2010 and measured cross-reactive neutralizing antibody titers against all 11 EV71 genotypes. In addition, we aligned and compared the amino acid sequences of P1 proteins of the tested viruses. RESULTS: Serology data showed that children infected with genogroups B and C consistently have lower neutralizing antibody titers against genogroup A (>4-fold difference. The sequence comparisons revealed that five amino acid signatures (N143D in VP2; K18R, H116Y, D167E, and S275A in VP1 are specific for genogroup A and may be related to the observed antigenic variations. CONCLUSIONS: This study documented antigenic variations among different EV71 genogroups and identified potential immunodominant amino acid positions. Enterovirus surveillance and vaccine development should monitor these positions.

  8. Detection of drug-dependent, platelet-reactive antibodies by solid-phase red cell adherence assays.

    Science.gov (United States)

    Leach, M F; Cooper, L K; AuBuchon, J P

    1997-06-01

    We developed a simple modification of the solid-phase red cell adherence (SPRCA) assay system that can be used to identify drug-dependent platelet antibodies (DDPAs) reactive by either the hapten or immune complex reaction mechanisms. Between January 1994 and August 1996 we tested sera from 173 patients [123 (71%) with unexplained thrombocytopenia and 50 (29%) because of poor responses to platelet transfusions not explicable by alloimmunization or the clinical situation] for DDPAs possibly associated with the receipt of 61 different drugs. We correlated positive results with patients' clinical courses. DDPAs were identified in samples from 138 (80%) of the patients tested. Antibodies reactive only by the hapten mechanism were identified in 51 (37%) of those sera exhibiting positive reactions. The clinical courses of 108 (78%) patients were evaluable. Discontinuation of the implicated drug(s) resulted in prompt (<5 d) resolution of the thrombocytopenia or improvement in response to transfusion in all of these patients. In four cases thrombocytopenia returned upon re-exposure to the implicated drug. This adaptation of SPRCA provides a simple means of investigating the possibility of DDPAs and documents a higher frequency of these antibodies than has previously been suspected.

  9. Broadly cross-reactive antibodies dominate the human B cell response against 2009 pandemic H1N1 influenza virus infection

    OpenAIRE

    2011-01-01

    The 2009 pandemic H1N1 influenza pandemic demonstrated the global health threat of reassortant influenza strains. Herein, we report a detailed analysis of plasmablast and monoclonal antibody responses induced by pandemic H1N1 infection in humans. Unlike antibodies elicited by annual influenza vaccinations, most neutralizing antibodies induced by pandemic H1N1 infection were broadly cross-reactive against epitopes in the hemagglutinin (HA) stalk and head domain of multiple influenza strains. T...

  10. Arizona cypress (Cupressus arizonica) pollen allergens. Identification of cross-reactive periodate-resistant and -sensitive epitopes with monoclonal antibodies.

    Science.gov (United States)

    Barletta, B; Tinghino, R; Corinti, S; Afferni, C; Iacovacci, P; Mari, A; Pini, C; Di Felice, G

    1998-06-01

    Species of the Cupressaceae family are a worldwide cause of respiratory allergies. We used monoclonal antibodies (mAbs) to investigate the presence and the nature of cross-reacting epitopes shared by various components within Cupressus arizonica pollen extract (CaE) or by CaE and pollen extract from C. sempervirens (CsE). mAbs were produced in mice immunized with whole CaE (4A6 and 5E6) or with the major allergen components (2D5). Their reactivity was investigated by ELISA and immunoblotting before and after CaE periodate treatment. Cross-reactivity was evaluated by ELISA inhibition and immunoblotting. mAbs 2D5 and 4A6 recognized periodate-resistant epitopes, whereas the mAb 5E6 reacted with a periodate-sensitive determinant. The former mAbs recognized epitopes present on CaE major allergen and also shared by other components. mAb 5E6 showed a spread reactivity on CaE, with exclusion of the major allergen. When the three mAbs were tested with CsE, a restricted pattern of reactivity to mAbs 2D5 and 4A6 was obtained, whereas mAb 5E6 maintained a spread reactivity. The CaE major allergen is represented by two components recognized by human IgE and sharing common epitopes, as proven by mAbs reactivity. The use of these mAbs demonstrates that cross-reactivity within CaE components and between CaE and CsE is due to the presence of periodate-sensitive as well as -resistant epitopes.

  11. Serological survey for antibodies reactive with Ehrlichia canis and E. chaffeensis in dogs from the Bloemfontein area, South Africa

    Directory of Open Access Journals (Sweden)

    A-M Pretorius

    1998-07-01

    Full Text Available Sera from 161 dogs in the Bloemfontein area in South Africa were tested for the presence of antibodies reactive with Ehrlichia canis and E. chaffeensis by indirect fluorescent antibody testing. Overall, 68 (42 % of the dogs had significant antibody titres (>1/64 against E. canis and 61 (38 % had significant titres (>1/64 against E. chaffeensis. Seven (11 % dogs had higher titres to E. chaffeensis than E. canis (1/2048 and 1/1024 (2 dogs; 1/1024 and 1/512 (2 dogs; 1/2048 and 1/512; 1/512 and 1/256 and 1/512 and <1/64, respectively. The remaining seropositive dogs had equal (n=26; 42 % or 2- (n=17; 25 %, 3- (n=13; 2% or 4-fold (n= 5; 7 % higher titres against E. canis. Dogs from economically depressed, high-density suburbs (60/112; 48 % had significantly higher prevalences of antibodies against E. canis than those from more affluent, low-density suburbs (8/49; 14 % (c2 19.38, p < 0.001. Higher titres to E. chaffeensis than E. canis were found in dogs from affluent, low-density suburbs (3/49 and in dogs from economically depressed, high-density suburbs (4/112.

  12. Serum or breast milk immunoglobulins mask the self-reactivity of human natural IgG antibodies.

    Science.gov (United States)

    Djoumerska-Alexieva, Iglika; Manoylov, Iliyan; Dimitrov, Jordan D; Tchorbanov, Andrey

    2014-04-01

    B cells producing IgG antibodies specific to a variety of self- or foreign antigens are a normal constituent of the immune system of all healthy individuals. These naturally occurring IgG antibodies are found in the serum, external secretions, and pooled human immunoglobulin preparations. They bind with low affinity to antigens, which can also be targets for pathologic autoantibodies. An enhancement of naturally occurring IgG autoantibody activity was observed after treatment of human IgG molecules with protein-destabilizing agents. We have investigated the interactions of human immunoglobulins that were obtained from serum or from breast milk of healthy individuals or IVIg with human liver antigens. Proteins from an individual serum or milk were isolated by two methods, one of which included exposure to low pH and the other did not. Purified serum, mucosal IgM, IgA, and the fraction containing immunoglobulin G F(ab')2 fragments each inhibited the binding of a single donor or pooled IgG to human liver antigens. Our study presents findings regarding the role of the breast milk or serum antibodies in blocking the self-reactivity of IgG antibodies. It supports the suggestion that not IVIg only, but also the pooled human IgM and IgA might possess a potent beneficial immunomodulatory activity in autoimmune patients.

  13. Studies on Preparation and Characteristics of Monoclonal Antibodies Against Enrofloxacin and Cross-Reactivity of Related Fluoroquinolones

    Institute of Scientific and Technical Information of China (English)

    CAI Qin-ren; ZENG Zhen-ling; YANG Gui-xiang; CHEN Zhang-liu

    2004-01-01

    An ester activation method was employed to couple enrofloxacin(ENFX) to the carrier proteins BSA and OVA. The conjugates ENFX-BSA and ENFX-OVA were identified with an UV spectrophotometer and amino acid automation analysis instrument, and resulted in conjugates with 48 ENFX molecules per carrier molecule(BSA). Splenocytes from mice immunized with ENFX-BSA were fused with SP2/0 myeloma cells and hybridomas secreting antibodies against enrofloxacin were selected and cloned. Two stable monoclonal antibodies, 2C5, 5D5 of the subclass IgG2a, were isolated. Using antibody 5D5, an indirect competitive inhibition enzyme-linked immunosorbent assay (Ci-ELISA) was developed for the quantitative detection of enrofloxacin and its metabolites. The IC50 of the standard curve was 21.67 ng mL-1 and the limit of detection for enrofloxacin was 0.13 ng mL-1. This method was sensitive and had a linear range from 0.13 to 10 000 ngmL-1 (r=-0.9782). Monoclonal antibody 5D5 exhibited high relative affinity to enrofloxacin, and the cross-reactivities with ciprofloxacin,marbofloxacin, sarafloxacin and danorfloxacin were 110.8, 27.40, 71.05 and 37.41%,respectively. Three non-fluoroquinolones of cefadroxil, chloramphenicol, sulfadimethoxine were tested and there was no cross-reaction between them.

  14. Reactivity of anti-thyroid antibodies to thyroglobulin tryptic fragments: comparison of autoimmune and non-autoimmune thyroid diseases

    Directory of Open Access Journals (Sweden)

    L.H.B. Boechat

    1999-04-01

    Full Text Available Studies concerning the antigenicity of thyroglobulin fragments allow the characterization of the epitopes but do not consider the role of heavier antigenic fragments that could result in vivo from the action of endoproteases. Here we assess the relative importance of the fragments obtained from thyroglobulin by limited proteolysis with trypsin and compare by immunoblotting their reactivity to serum from patients with autoimmune (Graves' disease and Hashimoto's thyroiditis and non-autoimmune (subacute thyroiditis disease. The results showed no difference in frequency of recognition of any peptide by sera from patients with autoimmune thyroiditis. In contrast, sera from patients with subacute thyroiditis reacted more frequently with a peptide of 80 kDa. These results suggest the presence of antibody subpopulations directed at fragments produced in vivo by enzymatic cleavage of thyroglobulin. This fragment and antibodies to it may represent markers for subacute thyroiditis.

  15. Development and characterization of a panel of cross-reactive monoclonal antibodies generated using H1N1 influenza virus.

    Science.gov (United States)

    Guo, Chun-yan; Tang, Yi-gui; Qi, Zong-li; Liu, Yang; Zhao, Xiang-rong; Huo, Xue-ping; Li, Yan; Feng, Qing; Zhao, Peng-hua; Wang, Xin; Li, Yuan; Wang, Hai-fang; Hu, Jun; Zhang, Xin-jian

    2015-08-01

    To characterize the antigenic epitopes of the hemagglutinin (HA) protein of H1N1 influenza virus, a panel consisting of 84 clones of murine monoclonal antibodies (mAbs) were generated using the HA proteins from the 2009 pandemic H1N1 vaccine lysate and the seasonal influenza H1N1(A1) vaccines. Thirty-three (39%) of the 84 mAbs were found to be strain-specific, and 6 (7%) of the 84 mAbs were subtype-specific. Twenty (24%) of the 84 mAbs recognized the common HA epitopes shared by 2009 pandemic H1N1, seasonal A1 (H1N1), and A3 (H3N2) influenza viruses. Twenty-five of the 84 clones recognized the common HA epitopes shared by the 2009 pandemic H1N1, seasonal A1 (H1N1) and A3 (H3N2) human influenza viruses, and H5N1 and H9N2 avian influenza viruses. We found that of the 16 (19%) clones of the 84 mAbs panel that were cross-reactive with human respiratory pathogens, 15 were made using the HA of the seasonal A1 (H1N1) virus and 1 was made using the HA of the 2009 pandemic H1N1 influenza virus. Immunohistochemical analysis of the tissue microarray (TMA) showed that 4 of the 84 mAb clones cross-reacted with human tissue (brain and pancreas). Our results indicated that the influenza virus HA antigenic epitopes not only induce type-, subtype-, and strain-specific monoclonal antibodies against influenza A virus but also cross-reactive monoclonal antibodies against human tissues. Further investigations of these cross-reactive (heterophilic) epitopes may significantly improve our understanding of viral antigenic variation, epidemics, pathophysiologic mechanisms, and adverse effects of influenza vaccines.

  16. Antibody reactivity against Helicobacter pylori proteins in a sample of the Spanish adult population in 2008-2013.

    Science.gov (United States)

    Fernández-de-Larrea, Nerea; Michel, Angelika; Romero, Beatriz; Butt, Julia; Pawlita, Michael; Pérez-Gómez, Beatriz; Castaño-Vinyals, Gemma; Moreno, Victor; Martín, Vicente; Amiano, Pilar; Castilla, Jesús; Fernández-Tardón, Guillermo; Dierssen-Sotos, Trinidad; Clofent, Juan; Alguacil, Juan; Huerta, José María; Jiménez-Moleón, José Juan; Barricarte, Aurelio; Molinuevo, Amaia; Fernández-Villa, Tania; Casabonne, Delphine; Sierra, Ángeles; Kogevinas, Manolis; de Sanjosé, Silvia; Pollán, Marina; Del Campo, Rosa; Waterboer, Tim; Aragonés, Nuria

    2017-10-01

    Differences in Helicobacter pylori protein expression have been related to the risk of severe gastric diseases. In Spain, a marked geographic pattern in gastric cancer mortality has long been reported. To characterize antibody reactivity patterns against 16 H. pylori proteins, by age, sex, and region of birth, in a large sample of the Spanish adult population. Antibody reactivity was quantified by H. pylori multiplex serology in a sample from the control group of the multicase-control study MCC-Spain. For this analysis, 2555 population-based controls were included. Each participant was classified as seropositive or seronegative for each protein according to specific cutoffs. Overall H. pylori seroprevalence was defined as positivity against ≥4 proteins. Descriptive analyses by age, sex, and region of birth were performed for both seroprevalence and seroreactivity (continuous measure). Differences among groups were tested by logistic and linear regression models. Overall H. pylori seroprevalence increased with age in both sexes. For ages 55-74, seroprevalence was lower in women than in men (84% vs 92%, Ppylori seropositive subjects, proteins with the highest seroprevalence were GroEL, NapA, HP231, and Omp. Seropositivity for most of the proteins increased or remained stable with age, rising mainly for CagA, GroEL, and HyuA in women. A clear cohort effect was not observed. This is the first study to describe the antibody patterns against 16 H. pylori proteins in the Spanish population. We found variability in the H. pylori antibody profiles according to both individual factors such as age and sex, and environmental factors such as the region of birth. The slightness of the reduction in seropositivity with decreasing age highlights the ongoing importance of this infection. © 2017 John Wiley & Sons Ltd.

  17. Cross-reactive Carbohydrate Determinant Contributes to the False Positive IgE Antibody to Peanut

    Directory of Open Access Journals (Sweden)

    Komei Ito

    2005-01-01

    Conclusions: Social education about the features of peanut allergy is needed in Japan. Anti-CCD IgE antibody was suggested to be one of the mechanisms contributing to the false positive detection of peanut IgE. Detection of anti-HRP or anti-bromelain IgE can be a useful tool to recognize the presence of anti-CCD antibodies.

  18. Development of an elisa for the diagnosis of reactive IgE antibodies anti-therapeutic horse sera.

    Science.gov (United States)

    De-Simone, Salvatore Giovanni; Souza, Andre Luis Almeida; Aguiar, Aniesse Silva; Melgarejo, Anibal Raphel; Provance-Jr, David William

    2017-08-12

    Hypersensitive diseases that involve IgE reactivity are important concern of public, especially those encompassing the potential pathogenesis from the administration of horse serum-based therapeutics such as antivenoms. A method for the definitive diagnosis of reactive IgE is important for identifying allergic patients to control severe collateral effects during planned and emergency application of immunotherapies when the allergy source cannot be avoided for treatment. To date, no tests have been developed to accompany the wide range of antivenoms produced from horse sera. The aim of this was to develop a cost-effective ELISA of high sensitivity and specificity to detect circulating patient IgE that binds horse IgG3, the most prevalent antibody class in passive antibody therapies. Horse IgG3 was purified in a single step on jacalin-Sepharose and absorbed to standard ELISA plates as the capture molecule for reactive human IgE. The direct performance evaluation with allergenic and non-allergenic patient, together with competitive peptides assays, showed high sensitivity and specificity to detect human IgE that recognized horse IgG3. The analytical sensitivity and ED50 were calculated to be 0.01 μg mL(-1) and 0.052 μg mL(-1), respectively. The intra- and inter-assay coefficient of variation ranged from 3.3 to 11.1% and 4.0-8.0%, respectively. The horse IgG3-based ELISA assay can detect reactive allergenic IgE at picomolar concentrations. The coefficient of variation suggests that it can be easily standardized between laboratories, provide rapid and can be applied to population surveillance. Patient management during treatment for envenomation would be greatly improved by a robust and reliable diagnostic test for preexisting allergies to mitigate life-threating consequences of hypersensitivity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Antibody repertoire profiling using bacterial display identifies reactivity signatures of celiac disease.

    Science.gov (United States)

    Spatola, Bradley N; Murray, Joseph A; Kagnoff, Martin; Kaukinen, Katri; Daugherty, Patrick S

    2013-01-15

    A general strategy to identify serum antibody specificities associated with a given disease state and peptide reagents for their detection was developed using bacterial display peptide libraries and multiparameter flow cytometry (MPFC). Using sera from patients with celiac disease (CD) (n = 45) or healthy subjects (n = 40), bacterial display libraries were screened for peptides that react specifically with antibodies from CD patients and not with those from healthy patients. The libraries were screened for peptides that simultaneously cross-react with CD patient antibodies present in two separate patient groups labeled with spectrally distinct fluorophores but do not react with unlabeled non-CD antibodies, thus affording a quantitative separation. A panel of six unique peptide sequences yielded 85% sensitivity and 91% specificity (AUC = 0.91) on a set of 60 samples not used for discovery, using leave-one-out cross-validation. Individual peptides were dissimilar with known CD-specific antigens tissue transglutaminase (tTG) and deamidated gliadin, and the classifier accuracy was independent of anti-tTG antibody titer. These results demonstrate that bacterial display/MPFC provides a highly effective tool for the unbiased discovery of disease-associated antibody specificities and peptide reagents for their detection that may have broad utility for diagnostic development.

  20. Differences in Glycoprotein Complex Receptor Binding Site Accessibility Prompt Poor Cross-Reactivity of Neutralizing Antibodies between Closely Related Arenaviruses.

    Science.gov (United States)

    Brouillette, Rachel B; Phillips, Elisabeth K; Ayithan, Natarajan; Maury, Wendy

    2017-04-01

    The glycoprotein complex (GPC) of arenaviruses, composed of stable signal peptide, GP1, and GP2, is the only antigen correlated with antibody-mediated neutralization. However, despite strong cross-reactivity of convalescent antisera between related arenavirus species, weak or no cross-neutralization occurs. Two closely related clade B viruses, Machupo virus (MACV) and Junín virus (JUNV), have nearly identical overall GPC architecture and share a host receptor, transferrin receptor 1 (TfR1). Given structural and functional similarities of the GP1 receptor binding site (RBS) of these viruses and the recent demonstration that the RBS is an important target for neutralizing antibodies, it is not clear how these viruses avoid cross-neutralization. To address this, MACV/JUNV chimeric GPCs were assessed for interaction with a group of α-JUNV GPC monoclonal antibodies (MAbs) and mouse antisera against JUNV or MACV GPC. All six MAbs targeted GP1, with those that neutralized JUNV GPC-pseudovirions competing with each other for RBS binding. However, these MAbs were unable to bind to a chimeric GPC composed of JUNV GP1 containing a small disulfide bonded loop (loop 10) unique to MACV GPC, suggesting that this loop may block MAbs interaction with the GP1 RBS. Consistent with this loop causing interference, mouse anti-JUNV GPC antisera that solely neutralized pseudovirions bearing autologous GP1 provided enhanced neutralization of MACV GPC when this loop was removed. Our studies provide evidence that loop 10, which is unique to MACV GP1, is an important impediment to binding of neutralizing antibodies and contributes to the poor cross-neutralization of α-JUNV antisera against MACV.IMPORTANCE Multiple New World arenaviruses can cause severe disease in humans, and some geographic overlap exists among these viruses. A vaccine that protects against a broad range of New World arenaviruses is desirable for purposes of simplicity, cost, and broad protection against multiple National

  1. Antibody Reactivity to Omp31 from Brucella melitensis in Human and Animal Infections by Smooth and Rough Brucellae

    Science.gov (United States)

    Cassataro, Juliana; Pasquevich, Karina; Bruno, Laura; Wallach, Jorge C.; Fossati, Carlos A.; Baldi, Pablo C.

    2004-01-01

    Group 3 of outer membrane proteins (OMPs) of Brucella includes Omp25 and Omp31, which share 34% identity. Omp25 is highly conserved in Brucella species, and Omp31 is present in all Brucella species, except Brucella abortus. Antibodies to Brucella melitensis Omp31 have been sought only in infected sheep, and Western blotting of sera from infected sheep did not reveal anti-Omp31 reactivity. We obtained recombinant purified Omp31 (B. melitensis) and tested its recognition by sera from humans and animals suffering from brucellosis by an indirect enzyme-linked immunosorbent assay (ELISA). Serum samples from 74 patients, 57 sheep, and 47 dogs were analyzed; brucellosis was confirmed by bacteriological isolation in all ovine and canine cases and 31 human cases of brucellosis. Thirty-five patients (47%) were positive for antibodies to Omp31, including seven cases of Brucella suis infection, two cases of B. abortus infection, and three cases of B. melitensis infection. Of 39 sheep naturally infected with B. melitensis (biovars 1 and 3), 23 (59%) were positive for antibodies to Omp31. Anti-Omp31 antibodies were also detected in 12 of 18 rams (67%) in which Brucella ovis was isolated from semen. Antibodies to Omp31 were also found in 41 (87%) of the 47 dogs, including 13 with recent infection. These results suggest that an indirect ELISA using recombinant purified Omp31 from B. melitensis would be of limited value for the diagnosis of human and animal brucellosis. Nevertheless, the potential usefulness of this antigen in combination with other recombinant proteins from Brucella should not be dismissed.   PMID:14715555

  2. A synthetic peptide derived from the animo acid sequence of canine parvovirus structural proteins which defines a B cell epitope and elicits antiviral antibody in BALB c mice.

    NARCIS (Netherlands)

    G.F. Rimmelzwaan (Guus); J. Carlson; F.G.C.M. Uytdehaag (Fons); A.D.M.E. Osterhaus (Albert)

    1990-01-01

    textabstractSynthetic peptides, recombinant fusion proteins and mouse monoclonal antibodies were used to delineate a B cell epitope of the VP'2 structural protein of canine parvovirus (CPV). Although this epitope is not preferentially recognized in the normal antibody response to CPV, virus-specific

  3. Expression characteristics and specific antibody reactivity of diverse cathepsin F members of Paragonimus westermani.

    Science.gov (United States)

    Ahn, Chun-Seob; Na, Byoung-Kuk; Chung, Dong-Ll; Kim, Jeong-Geun; Kim, Jin-Taek; Kong, Yoon

    2015-02-01

    Paragonimiasis, caused by the lung fluke Paragonimus, is a major food-borne helminthic disease. Differential diagnosis of paragonimiasis from tuberculosis and other infectious granulomas in the lung is a prerequisite to proper management of patients. Cysteine proteases of Paragonimus westermani (PwCPs) invoke specific antibody responses against patient sera, while antibody capturing activity of different PwCPs has not been comparatively analyzed. In this study, we observed the expressional regulation of 11 species of different PwCPs (PwCP1-11). We expressed recombinant PwCPs and assessed diagnostic reliability employing sera from patients with P. westermani (n=138), other trematodiases (n=80), cestodiases (n=60) and pulmonary tuberculosis (n=20), and those of normal controls (n=20). PwCPs formed a monophyletic clade into cathepsin F and showed differential expression patterns along with developmental stages of worm. Bacterially expressed recombinant PwCPs (rPwCPs) exhibited variable sensitivity of 38.4-84.5% and specificity of 87.2-100% in diagnosing homologous infection. rPwCPs recognized specific antibodies of experimental cat sera as early as 3 or 6weeks after infection. Patient sera of fascioliasis, Schistosomiasis japonicum and clonorchiasis demonstrated weak cross-reactions. Our results demonstrate that diverse PwCPs of the cathepsin F family participate in inducing specific antibody responses. Most P. westermani cathepsin F, except for PwCP2 (AAF21461), which showed negligible antibody responses, might be applicable for paragonimiasis serodiagnosis.

  4. Generation and molecular characterization of a monoclonal antibody reactive with conserved epitope in sphingomyelinases D from Loxosceles spider venoms.

    Science.gov (United States)

    Dias-Lopes, C; Felicori, L; Rubrecht, L; Cobo, S; Molina, L; Nguyen, C; Galéa, P; Granier, C; Molina, F; Chávez-Olortegui, C

    2014-04-11

    We report the production of a neutralizing monoclonal antibody able to recognize the venoms of three major medically important species of Loxosceles spiders in Brazil. The mAb was produced by immunization of mice with a toxic recombinant L. intermedia sphingomyelinase D {SMases D isoform (rLiD1)} [1] and screened by enzyme-linked immunosorbent assay (ELISA) using L. intermedia, L. laeta and L. gaucho venoms as antigens. One clone (LiD1mAb16) out of seventeen anti-rLiD1 hybridomas was cross-reactive with the three whole Loxosceles venoms. 2D Western blot analysis indicated that LiD1mAb16 was capable of interacting with 34 proteins of 29-36kDa in L. intermedia, 33 in L. gaucho and 27 in L. laeta venoms. The results of immunoassays with cellulose-bound peptides revealed that the LiD1mAb16 recognizes a highly conserved linear epitope localized in the catalytic region of SMases D toxins. The selected mAb displayed in vivo protective activity in rabbits after challenge with rLiD1. These results show the potential usefulness of monoclonal antibodies for future therapeutic approaches and also opens up the perspective of utilization of these antibodies for immunodiagnostic assays in loxoscelism.

  5. Anti Zn antibodies: cross reactivity and competitive binding with heavy metals.

    Science.gov (United States)

    Sarada, N C; Thamaraiselvi, K; Vijayalakshmi, M A

    2008-01-15

    Monoclonal antibodies of IgM class, specific to IDA-Zn were used for evaluating their Zn(2+) binding efficiency in the presence of trace metal ions such as Cr(3+) Cr(6+), Cu(2+) and Cd(2+). In the present work, antibody raised against the hapten IDA-Zn(II) was pre-incubated with different metal ions and the binding capacity to the specific hapten was tested using ELISA and immobilized metal ion affinity chromatography (IMAC) techniques. IMAC was carried out with the free antibody and antibody pre-incubated with selected heavy metal ions using Sepharose IDA-Zn(2+) column and the same samples were tested using a hapten specific ELISA with non-protein hapten carrier. Different effects were observed after pre-incubation with metal ions. Cr(3+) exhibited synergistic binding where as antagonism was detected with Cd(2+). The synergistic effect observed with Cr(3+) suggests involvement of binding sites other than that of zinc and conformational changes that result from Cr(3+) binding. It is probable that, this binding event also increases the accessibility of the zinc binding sites on IgM. On the same lines, the antagonism observed with Cd(2+) could be attributed to structural changes resulting in reduced accessibility to zinc binding sites. In case of Cr(6+), no appreciable change in binding to IDA-Zn was observed while Cu(2+) showed competitive binding.

  6. Inferring epitopes of a polymorphic antigen amidst broadly cross-reactive antibodies using protein microarrays: a study of OspC proteins of Borrelia burgdorferi.

    Directory of Open Access Journals (Sweden)

    Elisabeth Baum

    Full Text Available Epitope mapping studies aim to identify the binding sites of antibody-antigen interactions to enhance the development of vaccines, diagnostics and immunotherapeutic compounds. However, mapping is a laborious process employing time- and resource-consuming 'wet bench' techniques or epitope prediction software that are still in their infancy. For polymorphic antigens, another challenge is characterizing cross-reactivity between epitopes, teasing out distinctions between broadly cross-reactive responses, limited cross-reactions among variants and the truly type-specific responses. A refined understanding of cross-reactive antibody binding could guide the selection of the most informative subsets of variants for diagnostics and multivalent subunit vaccines. We explored the antibody binding reactivity of sera from human patients and Peromyscus leucopus rodents infected with Borrelia burgdorferi to the polymorphic outer surface protein C (OspC, an attractive candidate antigen for vaccine and improved diagnostics for Lyme disease. We constructed a protein microarray displaying 23 natural variants of OspC and quantified the degree of cross-reactive antibody binding between all pairs of variants, using Pearson correlation calculated on the reactivity values using three independent transforms of the raw data: (1 logarithmic, (2 rank, and (3 binary indicators. We observed that the global amino acid sequence identity between OspC pairs was a poor predictor of cross-reactive antibody binding. Then we asked if specific regions of the protein would better explain the observed cross-reactive binding and performed in silico screening of the linear sequence and 3-dimensional structure of OspC. This analysis pointed to residues 179 through 188 the fifth C-terminal helix of the structure as a major determinant of type-specific cross-reactive antibody binding. We developed bioinformatics methods to systematically analyze the relationship between local sequence

  7. Inferring epitopes of a polymorphic antigen amidst broadly cross-reactive antibodies using protein microarrays: a study of OspC proteins of Borrelia burgdorferi.

    Science.gov (United States)

    Baum, Elisabeth; Randall, Arlo Z; Zeller, Michael; Barbour, Alan G

    2013-01-01

    Epitope mapping studies aim to identify the binding sites of antibody-antigen interactions to enhance the development of vaccines, diagnostics and immunotherapeutic compounds. However, mapping is a laborious process employing time- and resource-consuming 'wet bench' techniques or epitope prediction software that are still in their infancy. For polymorphic antigens, another challenge is characterizing cross-reactivity between epitopes, teasing out distinctions between broadly cross-reactive responses, limited cross-reactions among variants and the truly type-specific responses. A refined understanding of cross-reactive antibody binding could guide the selection of the most informative subsets of variants for diagnostics and multivalent subunit vaccines. We explored the antibody binding reactivity of sera from human patients and Peromyscus leucopus rodents infected with Borrelia burgdorferi to the polymorphic outer surface protein C (OspC), an attractive candidate antigen for vaccine and improved diagnostics for Lyme disease. We constructed a protein microarray displaying 23 natural variants of OspC and quantified the degree of cross-reactive antibody binding between all pairs of variants, using Pearson correlation calculated on the reactivity values using three independent transforms of the raw data: (1) logarithmic, (2) rank, and (3) binary indicators. We observed that the global amino acid sequence identity between OspC pairs was a poor predictor of cross-reactive antibody binding. Then we asked if specific regions of the protein would better explain the observed cross-reactive binding and performed in silico screening of the linear sequence and 3-dimensional structure of OspC. This analysis pointed to residues 179 through 188 the fifth C-terminal helix of the structure as a major determinant of type-specific cross-reactive antibody binding. We developed bioinformatics methods to systematically analyze the relationship between local sequence/structure variation

  8. Cross-reactive Legionella antigens and the antibody response during infection

    DEFF Research Database (Denmark)

    Bangsborg, Jette Marie; Shand, G; Pearlman, E

    1991-01-01

    In order to define cross-reactive Legionella antigens suitable for diagnostic purposes, we investigated sonicate antigens from two Legionella species, including two serogroups of L. pneumophila. The antigens were reacted with heterologous and homologous rabbit antisera in Western blot. Sera from...

  9. Production of Nurr-1 Specific Polyclonal Antibodies Free of Cross-reactivity Against Its Close Homologs, Nor1 and Nur77.

    Science.gov (United States)

    Leblanc, Pierre; Moon, Minho; Kim, Woori; Jeong, Inhye; Kim, Chun-Hyung; Kim, Kwang-Soo

    2015-08-17

    The nuclear receptor subfamily 4 (NR4A) is composed of 3 related proteins sharing a DNA binding domain (DBD) and a ligand-binding domain (LBD). The nuclear receptor related 1 protein (Nurr1 or NR4A2) plays a key role in the maintenance of the dopaminergic system. Dopamine dysfunctions associated with the Nurr1 gene include Parkinson's disease, schizophrenia and manic depression among others. Furthermore, recent evidence indicates that Nurr1 is also expressed in other brain areas such as the hippocampus and plays critical roles for learning and memory. The other members of the family are nerve growth factor IB (Nur77 or NR4A1) and neuron-derived orphan receptor 1 (NOR1 or NR4A3). To help investigate the precise functional roles of Nurr1 in dopaminergic and other brain region-related neuronal dysfunctions antibodies devoid of cross-reactivities against Nur77 and NOR1 were needed. Since the proteins are more divergent in their LBDs than in their DNA binding domains immunization with purified LBDs should yield antibodies specific for Nurr1 with minimal reactivities against Nur77 and/or NOR1. Although anti-Nurr1 antibodies were successfully generated these showed significant immunoreactivity against the other members of the family. Affinity chromatography over immobilized Protein A followed by pre-adsorption against immobilized Nur77 and NOR1 LBDs yielded Nurr1 specific antibodies free of cross-reactivity. Here, we selectively target antibodies against a specific member of a highly conserved family of proteins by immunizing animals with their most divergent regions followed by removing cross reactive antibodies by pre-adsorption. The goal of the protocol is to increase polyclonal antibodies specificity through pre-adsorption against cross-reactive antigens.

  10. α-synuclein reactive antibodies as diagnostic biomarkers in blood sera of Parkinson's disease patients.

    Directory of Open Access Journals (Sweden)

    Kiran Yanamandra

    Full Text Available BACKGROUND: Auto-antibodies with specificity to self-antigens have been implicated in a wide variety of neurological diseases, including Parkinson's (PD and Alzheimer's diseases, being sensitive indicators of neurodegeneration and focus for disease prevention. Of particular interest are the studies focused on the auto-immune responses to amyloidogenic proteins associated with diseases and their applications in therapeutic treatments such as vaccination with amyloid antigens and antibodies in PD, Alzheimer's disease and potentially other neurodegeneration ailments. METHODOLOGY/PRINCIPAL FINDINGS: Generated auto-antibodies towards the major amyloidogenic protein involved in PD Lewy bodies--α-synuclein and its amyloid oligomers and fibrils were measured in the blood sera of early and late PD patients and controls by using ELISA, Western blot and Biacore surface plasmon resonance. We found significantly higher antibody levels towards monomeric α-synuclein in the blood sera of PD patients compared to controls, though the responses decreased with PD progression (P<0.0001. This indicates potential protective role of autoimmunity in maintaining the body homeostasis and clearing protein species whose disbalance may lead to amyloid assembly. There were no noticeable immune responses towards amyloid oligomers, but substantially increased levels of IgGs towards α-synuclein amyloid fibrils both in PD patients and controls, which subsided with the disease progression (P<0.0001. Pooled IgGs from PD patients and controls interacted also with the amyloid fibrils of Aβ (1-40 and hen lysozyme, however the latter were recognized with lower affinity. This suggests that IgGs bind to the generic amyloid conformational epitope, displaying higher specificity towards human amyloid species associated with neurodegeneration. CONCLUSIONS/SIGNIFICANCE: Our findings may suggest the protective role of autoimmunity in PD and therefore immune reactions towards PD major

  11. Perioperative use of iloprost in cardiac surgery patients diagnosed with heparin-induced thrombocytopenia-reactive antibodies or with true HIT (HIT-reactive antibodies plus thrombocytopenia): An 11-year experience.

    Science.gov (United States)

    Palatianos, George; Michalis, Alkiviadis; Alivizatos, Petros; Lacoumenda, Stavroula; Geroulanos, Stefanos; Karabinis, Andreas; Iliopoulou, Eugenia; Soufla, Giannoula; Kanthou, Chryso; Khoury, Mazen; Sfyrakis, Petros; Stavridis, George; Astras, George; Vassili, Maria; Antzaka, Christina; Marathias, Katerina; Kriaras, Ioannis; Tasouli, Androniki; Papadopoulos, Kyrillos; Katafygioti, Marina; Matoula, Nikoletta; Angelidis, Antonios; Melissari, Euthemia

    2015-07-01

    Thrombocytopenia and thromboembolism(s) may develop in heparin immune-mediated thrombocytopenia (HIT) patients after reexposure to heparin. At the Onassis Cardiac Surgery Center, 530 out of 17,000 patients requiring heart surgery over an 11-year period underwent preoperative HIT assessment by ELISA and a three-point heparin-induced platelet aggregation assay (HIPAG). The screening identified 110 patients with HIT-reactive antibodies, out of which 46 were also thrombocytopenic (true HIT). Cardiac surgery was performed in HIT-positive patients under heparin anticoagulation and iloprost infusion. A control group of 118 HIT-negative patients received heparin but no iloprost during surgery. For the first 20 patients, the dose of iloprost diminishing the HIPAG test to ≤5% was determined prior to surgery by in vitro titration using the patients' own plasma and donor platelets. In parallel, the iloprost "target dose" was also established for each patient intraoperatively, but before heparin administration. Iloprost was infused initially at 3 ng/kg/mL and further adjusted intraoperatively, until ex vivo aggregation reached ≤5%. As a close correlation was observed between the "target dose" identified before surgery and that established intraoperatively, the remaining 90 patients were administered iloprost starting at the presurgery identified "target dose." This process significantly reduced the number of intraoperative HIPAG reassessments needed to determine the iloprost target dose, and reduced surgical time, while maintaining similar primary clinical outcomes to controls. Therefore, infusion of iloprost throughout surgery, under continuous titration, allows cardiac surgery to be undertaken safely using heparin, while avoiding life-threatening iloprost-induced hypotension in patients diagnosed with HIT-reactive antibodies or true HIT. © 2015 Wiley Periodicals, Inc.

  12. Cross-reactivity of anti-H pylori antibodies with membrane antigens of human erythrocytes

    Institute of Scientific and Technical Information of China (English)

    Feng-Hua Guo; Fan-Ling Meng; Jian-Zhong Zhang; Xiao-Mei Yan; Chun-Xiang Fan; Fei Zhao; Yuan Hu; Di Xiao; Xun Zeng; Mao-Jun Zhang; Li-Hua He

    2007-01-01

    AIM: To investigate whether anti-H pylori antibodies have cross-reaction with antigens of erythrocyte membrane.METHODS: Blood samples were collected from 14 volunteers (8 positive and 6 negative for H pylori detected by 13C-urea breath test) of the general population. Erythrocyte membrane proteins of the subjects were examined by Western blot using antiH pylori serum. The proteins related to the positive bands were identified by mass spectrum analysis.RESULTS: Anti-H pylori antibodies had cross-reaction with the proteins of about 50 kDa of erythrocyte membranes in all samples independent of H pylori infection. One protein in the positive band was identified as Chain S, the crystal structure of the cytoplasmic domain of human erythrocyte Band-3 protein.CONCLUSION: Anti-H pylori antibodies cross-react with some antigens of human erythrocyte membrane, which may provide a clue for the relationship between H pylori infection and vascular disorders.

  13. Amino acid sequence diversity within the family of antibodies bearing the major antiarsonate cross-reactive idiotype of the A strain mouse

    OpenAIRE

    1983-01-01

    VH region amino acid sequences are described for five A/J anti-p- azophenylarsonate (anti-Ars) hybridoma antibodies for which the VL region sequences have previously been determined, thus completing the V domain sequences of these molecules. These antibodies all belong to the family designated Ars-A which bears the major anti-arsonate cross- reactive idiotype (CRI) of the A strain mouse. However, they differ in the degree to which they express the CRI in standard competition radioimmunoassays...

  14. Approaches to systems biology. Four methods to study single-cell gene expression, cell motility, antibody reactivity, and respiratory metabolism

    DEFF Research Database (Denmark)

    Hagedorn, Peter

    : Transcript profiling of one cell type extracted from a complex tissue containing several cell types; observation and recording of cell motility; measurement of antibody reactivities using microarrays; and invivo measurement of free and bound NADH in mitochondria. Detailed statistical analysis of the data......To understand how complex systems, such as cells, function, comprehensive Measurements of their constituent parts must be made. This can be achieved by combining methods that are each optimized to measure specific parts of the system. Four such methods,each covering a different area, are presented...... from such measurements allows models of the system to be developed and tested. For each of the methods, such analysis and modelling approaches have beenapplied and are presented: Differentially regulated genes are identified and classified according to function; cell-specfic motility models...

  15. Contribution of peptide backbone to Anti-citrulline-dependent antibody reactivity

    DEFF Research Database (Denmark)

    Trier, Nicole Hartwig; Dam, Catharina; Olsen, Dorthe

    2015-01-01

    Rheumatoid arthritis (RA) is one of the most common autoimmune diseases, affecting approximately 1–2% of the world population. One of the characteristic features of RA is the presence of autoantibodies. Especially the highly specific anti-citrullinated peptide antibodies (ACPAs), which have been...... homology rather than sequence homology are favored between citrullinated epitopes. These findings are important in relation to clarifying the etiology of RA and to determine the nature of ACPAs, e.g. why some Cit-Gly-containing sequences are not targeted by ACPAs....

  16. Exploiting Cross-reactivity to Neutralize Two Different Scorpion Venoms with One Single Chain Antibody Fragment*

    OpenAIRE

    Riaño-Umbarila, Lidia; Contreras-Ferrat, Gabriel; Olamendi-Portugal, Timoteo; Morelos-Juárez, Citlalli; Corzo, Gerardo; Possani, Lourival D.; Becerril, Baltazar

    2010-01-01

    We report the optimization of a family of human single chain antibody fragments (scFv) for neutralizing two scorpion venoms. The parental scFv 3F recognizes the main toxins of Centruroides noxius Hoffmann (Cn2) and Centruroides suffusus suffusus (Css2), albeit with low affinity. This scFv was subjected to independent processes of directed evolution to improve its recognition toward Cn2 (Riaño-Umbarila, L., Juárez-González, V. R., Olamendi-Portugal, T., Ortíz-León, M., Possani, L. D., and Bece...

  17. Humoral Immunity to Commensal Oral Bacteria in Human Infants: Salivary Antibodies Reactive with Actinomyces naeslundii Genospecies 1 and 2 during Colonization

    Science.gov (United States)

    Cole, Michael F.; Bryan, Stacey; Evans, Mishell K.; Pearce, Cheryl L.; Sheridan, Michael J.; Sura, Patricia A.; Wientzen, Raoul; Bowden, George H. W.

    1998-01-01

    The secretory immune response in saliva to colonization by Actinomyces naeslundii genospecies 1 and 2 was studied in 10 human infants from birth to 2 years of age. Actinomyces species were not recovered from the mouths of the infants until approximately 4 months after the eruption of teeth. However, low levels of secretory immunoglobulin A1 (SIgA1) and SIgA2 antibodies reactive with whole cells of A. naeslundii genospecies 1 and 2 were detected within the first month after birth. Although there was a fivefold increase in the concentration of SIgA between birth and age 2 years, there were no differences between the concentrations of SIgA1 and SIgA2 antibodies reactive with A. naeslundii genospecies 1 and 2 over this period. When the concentrations of SIgA1 and SIgA2 antibodies reactive with whole cells of A. naeslundii genospecies 1 and 2 were normalized to the concentrations of SIgA1 and SIgA2 in saliva, the A. naeslundii genospecies 1- and 2-reactive SIgA1 and SIgA2 antibodies showed a significant decrease from birth to 2 years of age. The fine specificities of A. naeslundii genospecies 1- and 2-reactive SIgA1 and SIgA2 antibodies were examined by Western blotting of envelope proteins. Similarities in the molecular masses of proteins recognized by SIgA1 and SIgA2 antibodies, both within and between subjects over time, were examined by cluster analysis and showed considerable variability. Taken overall, our data suggest that among the mechanisms Actinomyces species employ to persist in the oral cavity are the induction of a limited immune response and clonal replacement with strains differing in their antigen profiles. PMID:9712779

  18. Targeting natural killer cell reactivity by employing antibody to NKp46: implications for type 1 diabetes.

    Directory of Open Access Journals (Sweden)

    Rami Yossef

    Full Text Available Natural killer (NK cells belong to the innate lymphoid cells. Their cytotoxic activity is regulated by the delicate balance between activating and inhibitory signals. NKp46 is a member of the primary activating receptors of NK cells. We previously reported that the NKp46 receptor is involved in the development of type 1 diabetes (T1D. Subsequently, we hypothesized that blocking this receptor could prevent or hinder disease development. To address this goal, we developed monoclonal antibodies for murine NKp46. One mAb, named NCR1.15, recognizes the mouse homologue protein of NKp46, named Ncr1, and was able to down-regulate the surface expression of NKp46 on primary murine NK cells following antibody injection in vivo. Additionally, NCR1.15 treatments were able to down-regulate cytotoxic activity mediated by NKp46, but not by other NK receptors. To test our primary assumption, we examined T1D development in two models, non-obese diabetic mice and low-dose streptozotocin. Our results show a significantly lower incidence of diabetic mice in the NCR1.15-treated group compared to control groups. This study directly demonstrates the involvement of NKp46 in T1D development and suggests a novel treatment strategy for early insulitis.

  19. Current trends in management of hepatitis B virus reactivation in the biologic therapy era

    Institute of Scientific and Technical Information of China (English)

    Claudio M Mastroianni; Miriam Lichtner; Rita Citton; Cosmo Del Borgo; Angela Rago; Helene Martini; Giuseppe Cimino; Vincenzo Vullo

    2011-01-01

    Hepatitis B virus (HBV) reactivation represents an emerging cause of liver disease in patients undergoing treatment with biologic agents. In particular, the risk of HBV reactivation is heightened by the use monoclonal antibodies, such as rituximab (anti-CD20) and alemtuzumab (anti-CD52) that cause profound and long-lasting immunosuppression. Emerging data indicate that HBV reactivation could also develop following the use of other biologic agents, such as tumor necrosis factor (TNF)-α inhibitors. When HBV reactivation is diagnosed, it is mandatory to suspend biologic treatment and start antiviral agents immediately. However, pre-emptive antiviral therapy prior to monoclonal antibody administration is crucial in preventing HBV reactivation and its clinical consequences. Several lines of evidence have shown that risk of HBV reactivation is greatly reduced by the identification of high-risk patients and the use of prophylactic antiviral therapy. In this article, we discuss current trends in the management of HBV reactivation in immunosuppressed patients receiving biologic therapy, such as rituximab, alemtuzumab and TNF-α antagonists.

  20. Nerve growth factor antibody stimulates reactivation of ocular herpes simplex virus type 1 in latently infected rabbits.

    Science.gov (United States)

    Hill, J M; Garza, H H; Helmy, M F; Cook, S D; Osborne, P A; Johnson, E M; Thompson, H W; Green, L C; O'Callaghan, R J; Gebhardt, B M

    1997-06-01

    Anti-nerve growth factor (anti-NGF) antibody has been shown to induce reactivation of latent herpes simplex virus type 1 (HSV-1) in vitro. We found that systemically administered anti-NGF induces ocular shedding of HSV-1 in vivo in rabbits harboring latent virus. Rabbits in which HSV-1 latency had been established were given intravenous injections of goat anti-NGF serum daily for 10 days beginning 42 days after primary viral infection. Tears were assayed for virus for 12 days beginning on the day of the first injection. All eight rabbits given high titer anti-NGF had infectious virus in their tears at least once during the 12-day period. Fifteen of 16 eyes were positive and the average duration of viral shedding for these eyes was 4.0 days. Latently infected rabbits receiving daily injections of nonimmune goat serum or saline for 10 consecutive days were controls. Only six of the 16 (38%) eyes from rabbits receiving nonimmune goat serum shed virus. Only one of 12 eyes from untreated rabbits shed virus. Sera from control rabbits had no detectable anti-NGF activity; titers in anti-NGF-treated rabbits ranged between 1:1000 and 1:10,000. NGF deprivation may act as a neuronal stressor and may share a common second messenger pathway with heat- or cold-stress induced reactivation of latent HSV-1.

  1. Association of treatment-resistant chronic Lyme arthritis with HLA-DR4 and antibody reactivity to OspA and OspB of Borrelia burgdorferi.

    Science.gov (United States)

    Kalish, R A; Leong, J M; Steere, A C

    1993-01-01

    Chronic Lyme arthritis that is unresponsive to antibiotic therapy is associated with an increased frequency of the HLA-DR4 specificity. To determine whether the immune response to a particular polypeptide of Borrelia burgdorferi may be associated with treatment-resistant chronic Lyme arthritis, we correlated the clinical courses and HLA-DR specificities of 128 patients with Lyme disease with their antibody responses to spirochetal polypeptides. Antibody reactivity was determined by Western blotting (immunoblotting) with sonicated whole B. burgdorferi and recombinant forms of its outer surface proteins, OspA and OspB, as the antigen preparations. Of 15 patients monitored for 4 to 12 years, 11 (73%) developed strong immunoglobulin G responses to both OspA and OspB near the beginning of prolonged episodes of arthritis, from 5 months to 7 years after disease onset. When single serum samples from 80 patients with Lyme arthritis, were tested, 57 (71%) showed antibody reactivity to recombinant Osp proteins; in contrast, none of 43 patients who had erythema migrans or Lyme meningitis (P < 0.00001) and 1 of 5 patients who had chronic neuroborreliosis but who never had arthritis (P = 0.03) showed antibody reactivity to these proteins. Among the 60 antibiotic-treated patients with Lyme arthritis, those with the HLA-DR4 specificity and Osp reactivity had arthritis for a significantly longer time after treatment than those who lacked Osp reactivity (median duration, 9.5 versus 4 months; P = 0.009); a similar trend was found for the HLA-DR2 specificity. For other HLA-DR specificities, arthritis resolved within a median duration of 2 months in both Osp-reactive and nonreactive patients. We conclude that the combination of the HLA-DR4 specificity and OspA or OspB reactivity is associated with chronic arthritis and the lack of a response to antibiotic therapy. Images PMID:7685738

  2. Surface plasmon resonance-based competition assay to assess the sera reactivity of variants of humanized antibodies.

    Science.gov (United States)

    Gonzales, Noreen R; Schuck, Peter; Schlom, Jeffrey; Kashmiri, Syed V S

    2002-10-15

    While clinical trials are the only way to evaluate the immunogenicity, in patients, of murine or genetically engineered humanized variants of a potentially therapeutic or diagnostic monoclonal antibody (MAb), ethical and logistical considerations of clinical trials do not permit the evaluation of variants of a given MAb that are generated to minimize its immunogenicity. The most promising variant could be identified by comparing the reactivities of the parental antibody (Ab) and its variants to the sera of patients containing anti-variable region (anti-VR) Abs to the administered parental Ab. We have developed a surface plasmon resonance (SPR) biosensor-based assay to monitor the binding of the sera anti-VR Abs to the parental Ab and the inhibition of this binding by the variants. SPR biosensors allow the real-time detection and monitoring of the binding between an immobilized protein and its soluble ligand without the need for prior purification and labeling of the mobile analyte. This new assay requires no radiolabeling, is relatively less time-consuming, and uses only small amounts of serum (5-20 microl of diluted serum) through a new microfluidic sample handling technique. To validate the assay, we have tested the relative reactivities of the CDR-grafted anti-carcinoma Ab, HuCC49, and its two variants, designated V5 and V10, to the sera of patients who were earlier administered radiolabeled murine CC49 in a clinical trial. A comparison of IC(50)s (the concentrations of the competitor Abs required for 50% inhibition of the binding of sera to immobilized HuCC49) showed that V5 and V10 were less reactive than HuCC49 to the three patients' sera tested. We have also demonstrated, for the first time, the specific detection and comparison of relative amounts of anti-VR Abs present in the sera of different patients without prior removal of anti-murine Fc Abs and/or circulating antigen. This may facilitate the rapid screening, for the presence of anti-VR Abs, of the

  3. Induction of Murine Mucosal CCR5-Reactive Antibodies as an Anti-Human Immunodeficiency Virus Strategy

    Science.gov (United States)

    Barassi, C.; Soprana, E.; Pastori, C.; Longhi, R.; Buratti, E.; Lillo, F.; Marenzi, C.; Lazzarin, A.; Siccardi, A. G.; Lopalco, L.

    2005-01-01

    The genital mucosa is the main site of initial human immunodeficiency virus type 1 (HIV-1) contact with its host. In spite of repeated sexual exposure, some individuals remain seronegative, and a small fraction of them produce immunoglobulin G (IgG) and IgA autoantibodies directed against CCR5, which is probably the cause of the CCR5-minus phenotype observed in the peripheral blood mononuclear cells of these subjects. These antibodies recognize the 89-to-102 extracellular loop of CCR5 in its native conformation. The aim of this study was to induce infection-preventing mucosal anti-CCR5 autoantibodies in individuals at high risk of HIV infection. Thus, we generated chimeric immunogens containing the relevant CCR5 peptide in the context of the capsid protein of Flock House virus, a presentation system in which it is possible to engineer conformationally constrained peptide in a highly immunogenic form. Administered in mice via the systemic or mucosal route, the immunogens elicited anti-CCR5 IgG and IgA (in sera and vaginal fluids). Analogous to exposed seronegative individuals, mice producing anti-CCR5 autoantibodies express significantly reduced levels of CCR5 on the surfaces of CD4+ cells from peripheral blood and vaginal washes. In vitro studies have shown that murine IgG and IgA (i) specifically bind human and mouse CD4+ lymphocytes and the CCR5-transfected U87 cell line, (ii) down-regulate CCR5 expression of CD4+ cells from both humans and untreated mice, (iii) inhibit Mip-1β chemotaxis of CD4+ CCR5+ lymphocytes, and (iv) neutralize HIV R5 strains. These data suggest that immune strategies aimed at generating anti-CCR5 antibodies at the level of the genital mucosa might be feasible and represent a strategy to induce mucosal HIV-protective immunity. PMID:15890924

  4. An inhibition enzyme immunoassay, using a human monoclonal antibody (K14) reactive with gp41 of HIV-1, for the serology of HIV-1 infections.

    NARCIS (Netherlands)

    V.J.P. Teeuwsen; J.J. Schalken; G. van der Groen (Guido); R. van den Akker (Ruud); J. Goudsmit (Jaap); A.D.M.E. Osterhaus (Albert)

    1991-01-01

    textabstractAn inhibition enzyme immunoassay (IEIA), using a human monoclonal antibody (K14) reactive with gp41 of HIV-1, was evaluated for its applicability to the serology of HIV-1 infections. Using panels of serum samples from seronegative and confirmed HIV-1-seropositive individuals, it was show

  5. Broadly-Reactive Neutralizing and Non-neutralizing Antibodies Directed against the H7 Influenza Virus Hemagglutinin Reveal Divergent Mechanisms of Protection.

    Science.gov (United States)

    Tan, Gene S; Leon, Paul E; Albrecht, Randy A; Margine, Irina; Hirsh, Ariana; Bahl, Justin; Krammer, Florian

    2016-04-01

    In the early spring of 2013, Chinese health authorities reported several cases of H7N9 influenza virus infections in humans. Since then the virus has established itself at the human-animal interface in Eastern China and continues to cause several hundred infections annually. In order to characterize the antibody response to the H7N9 virus we generated several mouse monoclonal antibodies against the hemagglutinin of the A/Shanghai/1/13 (H7N9) virus. Of particular note are two monoclonal antibodies, 1B2 and 1H5, that show broad reactivity to divergent H7 hemagglutinins. Monoclonal antibody 1B2 binds to viruses of the Eurasian and North American H7 lineages and monoclonal antibody 1H5 reacts broadly to virus isolates of the Eurasian lineage. Interestingly, 1B2 shows broad hemagglutination inhibiting and neutralizing activity, while 1H5 fails to inhibit hemagglutination and demonstrates no neutralizing activity in vitro. However, both monoclonal antibodies were highly protective in an in vivo passive transfer challenge model in mice, even at low doses. Experiments using mutant antibodies that lack the ability for Fc/Fc-receptor and Fc/complement interactions suggest that the protection provided by mAb 1H5 is, at least in part, mediated by the Fc-fragment of the mAb. These findings highlight that a protective response to a pathogen may not only be due to neutralizing antibodies, but can also be the result of highly efficacious non-neutralizing antibodies not readily detected by classical in vitro neutralization or hemagglutination inhibition assays. This is of interest because H7 influenza virus vaccines induce only low hemagglutination inhibiting antibody titers while eliciting robust antibody titers as measured by ELISA. Our data suggest that these binding but non-neutralizing antibodies contribute to protection in vivo.

  6. Broadly-Reactive Neutralizing and Non-neutralizing Antibodies Directed against the H7 Influenza Virus Hemagglutinin Reveal Divergent Mechanisms of Protection.

    Directory of Open Access Journals (Sweden)

    Gene S Tan

    2016-04-01

    Full Text Available In the early spring of 2013, Chinese health authorities reported several cases of H7N9 influenza virus infections in humans. Since then the virus has established itself at the human-animal interface in Eastern China and continues to cause several hundred infections annually. In order to characterize the antibody response to the H7N9 virus we generated several mouse monoclonal antibodies against the hemagglutinin of the A/Shanghai/1/13 (H7N9 virus. Of particular note are two monoclonal antibodies, 1B2 and 1H5, that show broad reactivity to divergent H7 hemagglutinins. Monoclonal antibody 1B2 binds to viruses of the Eurasian and North American H7 lineages and monoclonal antibody 1H5 reacts broadly to virus isolates of the Eurasian lineage. Interestingly, 1B2 shows broad hemagglutination inhibiting and neutralizing activity, while 1H5 fails to inhibit hemagglutination and demonstrates no neutralizing activity in vitro. However, both monoclonal antibodies were highly protective in an in vivo passive transfer challenge model in mice, even at low doses. Experiments using mutant antibodies that lack the ability for Fc/Fc-receptor and Fc/complement interactions suggest that the protection provided by mAb 1H5 is, at least in part, mediated by the Fc-fragment of the mAb. These findings highlight that a protective response to a pathogen may not only be due to neutralizing antibodies, but can also be the result of highly efficacious non-neutralizing antibodies not readily detected by classical in vitro neutralization or hemagglutination inhibition assays. This is of interest because H7 influenza virus vaccines induce only low hemagglutination inhibiting antibody titers while eliciting robust antibody titers as measured by ELISA. Our data suggest that these binding but non-neutralizing antibodies contribute to protection in vivo.

  7. Development and precise characterization of phospho-site-specific antibody of Ser(357) of IRS-1: elimination of cross reactivity with adjacent Ser(358).

    Science.gov (United States)

    Waraich, Rizwana Sanaullah; Zaidi, Nousheen; Moeschel, Klaus; Beck, Alexander; Weigert, Cora; Voelter, Wolfgang; Kalbacher, Hubert; Lehmann, Rainer

    2008-11-07

    Antibodies that recognize specifically phosphorylated sites on proteins are widely utilized for studying the regulation and biological function of phosphoproteins. The proposed strategy is a powerful, analytical tool allowing the generation of phospho-site specific antibodies albeit adjacent phosphorylation sites are present. Here, we demonstrate the assessment and elimination of cross reactivity of phospho-site-specific-Ser(357) IRS-1 antibody. While determining the specificity of p-Ser(357) antiserum we came across the cross reactivity of the antiserum with adjacent Ser(358) which was successfully abolished by an improved immuno-purification method. The specificity of the purified antiserum was then verified by indirect ELISA, results of ELISA were also mirrored in the experiments carried out in BHK-IR cells using different mutants of IRS-1 carrying mutations at either Ser(357)/Ser(358)/Ser(357/358). Immuno-purified-p-Ser(357) did not react with IRS-1 Ala(357) and IRS-1 Ala(357/358). In conclusion, the present study describes generation and characterization of p-Ser(357) IRS-1 antibody, which reacts with IRS-1 in site specific and phosphorylation state-dependent manner without showing cross reactivity to adjacent Ser(358). This antibody can be effectively used to further clarify the inhibitory role of Ser(357) in insulin signal transduction.

  8. Reactivity of a monoclonal antibody with tissues and tumors from the human breast. Immunohistochemical localization of a new antigen and clinicopathologic correlations.

    Science.gov (United States)

    Mariani-Costantini, R; Barbanti, P; Colnaghi, M I; Ménard, S; Clemente, C; Rilke, F

    1984-04-01

    The reactions of a monoclonal antibody to the MCF7 breast cancer cell line were immunohistochemically studied on a variety of breast tumors, primary and metastatic, on mammary epithelium and on nonneoplastic breast lesions. A high proportion of positive reactions was observed in ductal, lobular, and tubular carcinomas as well as in mammary Paget's disease. Mucinous, medullary, and papillary carcinomas showed a low incidence of reactivity. Carcinomas with metaplasia, carcinoids, and nonepithelial breast tumors were unreactive with the antibody. Positive immunostaining was documented also in nodal and extranodal metastatic lesions. The staining of nodal metastases was correlated with the positive reaction of the primary tumor. Reactivity was widely distributed in normal breast epithelial cells and in benign breast lesions. Staining of nonneoplastic mammary epithelial was associated with reactivity of adjacent neoplastic tissues. Staining differences between nonneoplastic and neoplastic mammary tissues were related to the intensity and cytologic distribution of the labeling. Heterogeneous reactivity of morphologically similar cells was documented in nonneoplastic and neoplastic breast epithelial cells as well as in nodal and extranodal breast carcinoma metastases. Immunohistologically detectable antigen was not correlated with prognostic factors such as histologic grade or nodal status. A retrospective study of T1NO cases failed to substantiate any prognostic value for the reactivity of primary breast tumors with this monoclonal antibody.

  9. RNA sensors enable human mast cell anti-viral chemokine production and IFN-mediated protection in response to antibody-enhanced dengue virus infection.

    Directory of Open Access Journals (Sweden)

    Michael G Brown

    Full Text Available Dengue hemorrhagic fever and/or dengue shock syndrome represent the most serious pathophysiological manifestations of human dengue virus infection. Despite intensive research, the mechanisms and important cellular players that contribute to dengue disease are unclear. Mast cells are tissue-resident innate immune cells that play a sentinel cell role in host protection against infectious agents via pathogen-recognition receptors by producing potent mediators that modulate inflammation, cell recruitment and normal vascular homeostasis. Most importantly, mast cells are susceptible to antibody-enhanced dengue virus infection and respond with selective cytokine and chemokine responses. In order to obtain a global view of dengue virus-induced gene regulation in mast cells, primary human cord blood-derived mast cells (CBMCs and the KU812 and HMC-1 mast cell lines were infected with dengue virus in the presence of dengue-immune sera and their responses were evaluated at the mRNA and protein levels. Mast cells responded to antibody-enhanced dengue virus infection or polyinosiniċpolycytidylic acid treatment with the production of type I interferons and the rapid and potent production of chemokines including CCL4, CCL5 and CXCL10. Multiple interferon-stimulated genes were also upregulated as well as mRNA and protein for the RNA sensors PKR, RIG-I and MDA5. Dengue virus-induced chemokine production by KU812 cells was significantly modulated by siRNA knockdown of RIG-I and PKR, in a negative and positive manner, respectively. Pretreatment of fresh KU812 cells with supernatants from dengue virus-infected mast cells provided protection from subsequent infection with dengue virus in a type I interferon-dependent manner. These findings support a role for tissue-resident mast cells in the early detection of antibody-enhanced dengue virus infection via RNA sensors, the protection of neighbouring cells through interferon production and the potential recruitment of

  10. Antigen-binding properties of monoclonal antibodies reactive with EBNA1 and use in immunoaffinity chromatography.

    Directory of Open Access Journals (Sweden)

    Sarah J Duellman

    Full Text Available Epstein-Barr virus (EBV nuclear antigen 1 (EBNA1 was overexpressed and purified from Escherichia coli. Mouse monoclonal antibodies (mAbs were prepared that react with EBNA1. Eleven high affinity mAbs were recovered. Nine mAbs are isotype IgG (all subisotype IgG(1 and two mAbs are isotype IgM. All mAbs react strongly with EBNA1 in an ELISA assay while only one mAb (designated 1EB6 fails to react in a Western blot assay. The epitopes for these mAbs were mapped to seven different regions, providing good coverage of the entire EBNA1 protein. The mAbs had differing affinity for an EBNA1/DNA complex with four mAbs able to supershift the complex completely. All mAbs can immunoprecipitate EBNA1 from E. coli overexpressing EBNA1. A modified ELISA assay, termed ELISA-elution assay, was used to screen for mAbs that release EBNA1 in the presence of a low molecular weight polyhydroxylated compound (polyol and a nonchaotropic salt. MAbs with this property, termed polyol-responsive (PR-mAbs, allow gentle elution of labile proteins and protein complexes. Four mAbs are polyol-responsive with two showing usefulness in gentle immunoaffinity chromatography. Purification with these PR-mAbs may be useful in purifying EBNA1 complexes and elucidating EBNA1-associated proteins. This panel of anti-EBNA1 mAbs will advance the study of EBV by providing new tools to detect and purify EBNA1.

  11. Rapid Screening for Potential Epitopes Reactive with a Polycolonal Antibody by Solution-Phase H/D Exchange Monitored by FT-ICR Mass Spectrometry

    Science.gov (United States)

    Zhang, Qian; Noble, Kyle A.; Mao, Yuan; Young, Nicolas L.; Sathe, Shridhar K.; Roux, Kenneth H.; Marshall, Alan G.

    2013-07-01

    The potential epitopes of a recombinant food allergen protein, cashew Ana o 2, reactive to polyclonal antibodies, were mapped by solution-phase amide backbone H/D exchange (HDX) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Ana o 2 polyclonal antibodies were purified in the serum from a goat immunized with cashew nut extract. Antibodies were incubated with recombinant Ana o 2 (rAna o 2) to form antigen:polyclonal antibody (Ag:pAb) complexes. Complexed and uncomplexed (free) rAna o 2 were then subjected to HDX-MS analysis. Four regions protected from H/D exchange upon pAb binding are identified as potential epitopes and mapped onto a homologous model.

  12. Sero-prevalence and cross-reactivity of chikungunya virus specific anti-E2EP3 antibodies in arbovirus-infected patients.

    Directory of Open Access Journals (Sweden)

    Yiu-Wing Kam

    2015-01-01

    Full Text Available Chikungunya virus (CHIKV and clinically-related arboviruses cause large epidemics with serious economic and social impact. As clinical symptoms of CHIKV infections are similar to several flavivirus infections, good detection methods to identify CHIKV infection are desired for improved treatment and clinical management. The strength of anti-E2EP3 antibody responses was explored in a longitudinal study on 38 CHIKV-infected patients. We compared their anti-E2EP3 responses with those of patients infected with non-CHIKV alphaviruses, or flaviviruses. E2EP3 cross-reactive samples from patients infected with non-CHIKV viruses were further analyzed with an in vitro CHIKV neutralization assay. CHIKV-specific anti-E2EP3 antibody responses were detected in 72% to 100% of patients. Serum samples from patients infected with other non-CHIKV alphaviruses were cross-reactive to E2EP3. Interestingly, some of these antibodies demonstrated clearly in vitro CHIKV neutralizing activity. Contrastingly, serum samples from flaviviruses-infected patients showed a low level of cross-reactivity against E2EP3. Using CHIKV E2EP3 as a serology marker not only allows early detection of CHIKV specific antibodies, but would also allow the differentiation between CHIKV infections and flavivirus infections with 93% accuracy, thereby allowing precise acute febrile diagnosis and improving clinical management in regions newly suffering from CHIKV outbreaks including the Americas.

  13. Myelin-reactive antibodies initiate T cell-mediated CNS autoimmune disease by opsonization of endogenous antigen.

    Science.gov (United States)

    Kinzel, Silke; Lehmann-Horn, Klaus; Torke, Sebastian; Häusler, Darius; Winkler, Anne; Stadelmann, Christine; Payne, Natalie; Feldmann, Linda; Saiz, Albert; Reindl, Markus; Lalive, Patrice H; Bernard, Claude C; Brück, Wolfgang; Weber, Martin S

    2016-07-01

    In the pathogenesis of central nervous system (CNS) demyelinating disorders, antigen-specific B cells are implicated to act as potent antigen-presenting cells (APC), eliciting waves of inflammatory CNS infiltration. Here, we provide the first evidence that CNS-reactive antibodies (Ab) are similarly capable of initiating an encephalitogenic immune response by targeting endogenous CNS antigen to otherwise inert myeloid APC. In a transgenic mouse model, constitutive production of Ab against myelin oligodendrocyte glycoprotein (MOG) was sufficient to promote spontaneous experimental autoimmune encephalomyelitis (EAE) in the absence of B cells, when mice endogenously contained MOG-recognizing T cells. Adoptive transfer studies corroborated that anti-MOG Ab triggered activation and expansion of peripheral MOG-specific T cells in an Fc-dependent manner, subsequently causing EAE. To evaluate the underlying mechanism, anti-MOG Ab were added to a co-culture of myeloid APC and MOG-specific T cells. At otherwise undetected concentrations, anti-MOG Ab enabled Fc-mediated APC recognition of intact MOG; internalized, processed and presented MOG activated naïve T cells to differentiate in an encephalitogenic manner. In a series of translational experiments, anti-MOG Ab from two patients with an acute flare of CNS inflammation likewise facilitated detection of human MOG. Jointly, these observations highlight Ab-mediated opsonization of endogenous CNS auto-antigen as a novel disease- and/or relapse-triggering mechanism in CNS demyelinating disorders.

  14. Outcomes in the highest panel reactive antibody recipients of deceased donor kidneys under the new kidney allocation system.

    Science.gov (United States)

    Parajuli, Sandesh; Redfield, Robert R; Astor, Brad C; Djamali, Arjang; Kaufman, Dixon B; Mandelbrot, Didier A

    2017-03-01

    Since the institution of the new kidney allocation system in December 2014, kidney transplant candidates with the highest calculated panel reactive antibodies (cPRA) of 99-100 have been transplanted at much higher rates. However, concerns have been raised that outcomes in these patients might be impaired due to higher immunological risk and longer cold ischemia times resulting from long-distance sharing of kidneys. Here, we compare outcomes at the University of Wisconsin between study patients with cPRA 99-100 and all other recipients of deceased donor kidneys transplanted between 12/04/2014 and 12/31/2015. All patients had at least 6 months post-transplant follow-up. The mean follow-up was 13.9±3 months in cPRA ≥99% and 12.3±3.5 months in cPRA ≤98%. There was a total of 152 transplants, 25 study patients, and 127 controls. No statistically significant differences were found between the two groups in delayed graft function, rejection, kidney function, graft and patient survival, or infections. We conclude that transplanting the most highly sensitized patients with kidneys shared outside their local donation service areas is associated with excellent short-term outcomes that are comparable to controls. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Monoclonal antibodies to Escherichia coli F1-ATPase. Correlation of binding site location with interspecies cross-reactivity and effects on enzyme activity.

    Science.gov (United States)

    Dunn, S D; Tozer, R G; Antczak, D F; Heppel, L A

    1985-09-05

    Twenty-one hybridoma cell lines which secret antibodies to the subunits of the Escherichia coli F1-ATPase were produced. Included within the set are four antibodies which are specific for alpha, six for beta, three for gamma, four for delta and four for epsilon. The antibodies were divided into binding competition subgroups. Two such competition subgroups are represented for the alpha, beta, and epsilon subunits, one for delta and three for gamma. The ability to bind intact F1-ATPase was demonstrated for some of the antibodies to alpha and beta, and for all of those to delta, while the antibodies to gamma and epsilon gave unclear results. All of the antibodies to alpha and beta which bound ATPase were found to have effects on the ATPase activity of purified E. coli F1-ATPase. One of those to alpha inhibited activity by about 30%. Another anti-alpha was mildly stimulatory. The four antibodies to beta which bound ATPase inhibited activity by 90%. In contrast, membrane-bound ATPase was hardly affected by the antibodies to alpha, but was inhibited by 40-60% by the antibodies to beta. The other antibodies to alpha and beta bound only free subunits, or partially dissociated ATPase, suggesting that their epitopes are buried between subunits in ATPase. These antibodies had no effects on activity. The ability of the antibodies to recognize ATPase subunits present in crude extracts from mitochondria, chloroplasts, and a variety of bacteria was tested using nitrocellulose blots of sodium dodecyl sulfate-polyacrylamide gels. One anti-beta specifically recognized proteins in the range of 50,000-60,000 daltons in each of the extracts, although the reaction with mitochondrial beta was weak. Some of the other antibodies had limited cross-reaction, but most were specific for the E. coli protein. In some species, those proteins which were recognized by the anti-beta ran with a higher apparent molecular weight than proteins which were recognized by an anti-alpha. All antibodies which

  16. Antiviral, anti-parasitic, and cytotoxic effects of 5,6-dihydroxyindole (DHI), a reactive compound generated by phenoloxidase during insect immune response.

    Science.gov (United States)

    Zhao, Picheng; Lu, Zhiqiang; Strand, Michael R; Jiang, Haobo

    2011-09-01

    Phenoloxidase (PO) and its activation system are implicated in several defense responses of insects. Upon wounding or infection, inactive prophenoloxidase (proPO) is converted to active PO through a cascade of serine proteases and their homologs. PO generates reactive compounds such as 5,6-dihydroxyindole (DHI), which have a broad-spectrum antibacterial and antifungal activity. Here we report that DHI and its spontaneous oxidation products are also active against viruses and parasitic wasps. Preincubation of a baculovirus stock with 1.25 mM DHI for 3 h near fully disabled recombinant protein production. The LC₅₀ for lambda bacteriophage and eggs of the wasp Microplitis demolitor were 5.6 ± 2.2 and 111.0 ± 1.6 μM, respectively. The toxicity of DHI and related compounds also extended to cells derived from insects that serve as hosts for several of the aforementioned pathogens. Pretreatment of Sf9 cells with 1.0 mM DHI for 4 h resulted in 97% mortality, and LC₅₀ values of 20.3 ± 1.2 μM in buffer and 131.8 ± 1.1 μM in a culture medium. Symptoms of DHI toxicity in Sf9 cells included DNA polymerization, protein crosslinking, and lysis. Taken together, these data showed that proPO activation and DHI production is strongly toxic against various pathogens but can also damage host tissues and cells if not properly controlled.

  17. Presence of antibodies against a cell-surface protein, cross-reactive with DNA, in systemic lupus erythrematosus: a marker of the disease

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    Jacob, L.; Lety, M.A.; Choquette, D.; Viard, J.P.; Jacob, F.; Louvard, D.; Bach, J.F.

    1987-05-01

    Antibodies against a cell-surface protein, cross-reactive with double-stranded DNA, were detected in the serum of 25 patients with active human systemic lupus erythematosus (SLE), defined on the basis of the revised American Rheumatism Association classification. Among these sera, two did not display anti-DNA antibodies, as shown by Farr assay, solid-phase radioimmunoassay, and Crithidia luciliae test. Five other SLE patients were consecutively studied in active and remission states. Antibodies against the protein were detected in the serum of the 5 SLE patients when they were in active phase but not in the serum of the same patients in inactive phase of the disease. The anti-protein antibodies were not found in the serum of 10 inactive SLE patients or in the sera of 10 normal human controls, 10 patients with rheumatoid arthritis, 5 patients with scleroderma, and 4 patients with primary sicca syndrome. Taken together, these results strongly suggest that antibodies against this cell-surface protein could provide a better diagnosis marker and activity index than anti-DNA antibodies in SLE.

  18. Human Papillomavirus neutralizing and cross-reactive antibodies induced in HIV-positive subjects after vaccination with quadrivalent and bivalent HPV vaccines.

    Science.gov (United States)

    Faust, Helena; Toft, Lars; Sehr, Peter; Müller, Martin; Bonde, Jesper; Forslund, Ola; Østergaard, Lars; Tolstrup, Martin; Dillner, Joakim

    2016-03-18

    Ninety-one HIV-infected individuals (61 men and 30 women) were randomized to vaccination either with quadrivalent (Gardasil™) or bivalent (Cervarix™) HPV vaccine. Neutralizing and specific HPV-binding serum antibodies were measured at baseline and 12 months after the first vaccine dose. Presence of neutralizing and binding antibodies had good agreement (average Kappa for HPV types 6, 11, 16, 18, 31, 33 and 45 was 0.65). At baseline, 88% of subjects had antibodies against at least one genital HPV. Following vaccination with Cervarix™, all subjects became seropositive for HPV16 and 18. After Gardasil™ vaccination, 96% of subjects seroconverted for HPV16 and 73% for HPV18. Levels of HPV16-specific antibodies were vaccination but >10IU in 85% of study subjects after vaccination. Antibodies against non-vaccine HPV types appeared after Gardasil™ vaccination for >50% of vaccinated females for HPV 31, 35 and 73 and for >50% of Cervarix™-vaccinated females for HPV 31, 33, 35, 45, 56 and 58. Cross-reactivity with non-genital HPV types was also detected. In conclusion, HIV-infected subjects responded to HPV vaccination with induction of neutralizing antibodies against both vaccine and non-vaccine types.

  19. Reactivation of persistent Epstein-Barr virus (EBV) causes secretion of thyrotropin receptor antibodies (TRAbs) in EBV-infected B lymphocytes with TRAbs on their surface.

    Science.gov (United States)

    Nagata, Keiko; Nakayama, Yuji; Higaki, Katsumi; Ochi, Marika; Kanai, Kyosuke; Matsushita, Michiko; Kuwamoto, Satoshi; Kato, Masako; Murakami, Ichiro; Iwasaki, Takeshi; Nanba, Eiji; Kimura, Hiroshi; Hayashi, Kazuhiko

    2015-01-01

    Epstein-Barr virus (EBV) is a ubiquitous virus that infects most adults latently. It persists in B lymphocytes and reactivates occasionally. Graves' disease is an autoimmune hyperthyroidism caused by thyrotropin receptor antibodies (TRAbs). We have reported that Graves' disease patients and healthy controls have EBV-infected lymphocytes that have TRAbs on their surface (TRAb(+)EBV(+) cells) in peripheral blood mononuclear cells (PBMCs). EBV reactivation is known to be associated with plasma cell differentiation and antibody production of B cells. In this study, we investigated whether TRAb(+)EBV(+) cells really produce TRAbs or not when persistent EBV is reactivated. We cultured PBMCs from 12 Graves' disease patients and 12 healthy controls for several days with cyclosporine A to expand the EBV-infected cell population, and then compared TRAb levels between EBV reactivation by 33 °C culture and EBV nonreactivation by 37 °C culture of PBMCs. Flow cytometry confirmed that all samples at day 0 (reactivation starting point) contained TRAb(+)EBV(+) cells. During 33 °C culture, EBV-reactivated cells with EBV-gp350/220 expression increased from about 1 to 4%. We quantified TRAb levels in culture fluids by radio-receptor assay, and detected an increased concentration for at least one sampling point at 33 °C (from days 0 to 12) for all patients and healthy controls. TRAb levels were significantly higher in supernatants of 33 °C culture than of 37 °C culture, and also significantly higher in supernatants from patients than those from controls. This study revealed TRAb production from TRAb(+)EBV(+) cells in response to reactivation induction of persistent EBV in different efficiencies between patients and controls.

  20. Facial recognition of heroin vaccine opiates: type 1 cross-reactivities of antibodies induced by hydrolytically stable haptenic surrogates of heroin, 6-acetylmorphine, and morphine.

    Science.gov (United States)

    Matyas, Gary R; Rice, Kenner C; Cheng, Kejun; Li, Fuying; Antoline, Joshua F G; Iyer, Malliga R; Jacobson, Arthur E; Mayorov, Alexander V; Beck, Zoltan; Torres, Oscar B; Alving, Carl R

    2014-03-14

    Novel synthetic compounds similar to heroin and its major active metabolites, 6-acetylmorphine and morphine, were examined as potential surrogate haptens for the ability to interface with the immune system for a heroin vaccine. Recent studies have suggested that heroin-like haptens must degrade hydrolytically to induce independent immune responses both to heroin and to the metabolites, resulting in antisera containing mixtures of antibodies (type 2 cross-reactivity). To test this concept, two unique hydrolytically stable haptens were created based on presumed structural facial similarities to heroin or to its active metabolites. After conjugation of a heroin-like hapten (DiAmHap) to tetanus toxoid and mixing with liposomes containing monophosphoryl lipid A, high titers of antibodies after two injections in mice had complementary binding sites that exhibited strong type 1 ("true") specific cross-reactivity with heroin and with both of its physiologically active metabolites. Mice immunized with each surrogate hapten exhibited reduced antinociceptive effects caused by injection of heroin. This approach obviates the need to create hydrolytically unstable synthetic heroin-like compounds to induce independent immune responses to heroin and its active metabolites for vaccine development. Facial recognition of hydrolytically stable surrogate haptens by antibodies together with type 1 cross-reactivities with heroin and its metabolites can help to guide synthetic chemical strategies for efficient development of a heroin vaccine.

  1. The cross-reactivity of binding antibodies with different interferon beta formulations used as disease-modifying drugs in multiple sclerosis patients.

    Science.gov (United States)

    Wencel-Warot, Agnieszka; Michalak, Slawomir; Warot, Marcin; Kalinowska-Lyszczarz, Alicja; Kazmierski, Radoslaw

    2016-11-01

    Interferon beta (IFNb) preparations are commonly used as first-line therapy in relapsing-remitting multiple sclerosis (RRMS). They are, however, characterized by limited efficacy, partly due to the formation of anti-IFNb antibodies in patients.In this pilot study, we assessed with the ELISA method the presence of the binding antibodies (BAbs) against interferon beta after 2 years of therapy with subcutaneous interferon beta 1a (Rebif) in 49 RRMS patients. Antibody levels were established again within 1 year after treatment withdrawal. We used 3 interferons that are commercially available for MS therapy, namely Avonex (Biogen Idec Limited), Rebif (Merck Serono), and Betaferon (Bayer Pharma AG), as antigens.BAbs reacting with Rebif were found in 24.4% to 55% of patients, depending on the units of their expression. The levels of anti-Rebif antibodies remained high in 8 patients and in 4 patients they dropped significantly. Strong correlations were obtained in all assays (anti-Rebif-anti-Avonex, anti-Rebif-anti-Betaferon, and anti-Betaferon-anti-Avonex) and the existence of cross-reactivity in the formation of antibodies against all the tested formulations of interferon beta was confirmed. The levels of BAbs remain significant in the clinical context, and their assessment is the first choice screening; however, methods of BAbs evaluation can be crucial for further decisions. More studies are needed to confirm our results; specifically it would be of interest to evaluate methods of neutralizing antibodies identification, as we only assessed the binding antibodies. Nevertheless, our results support the concept that in interferon nonresponders, that are positive for binding antibodies, switching the therapy to alternative disease-modifying agent (for example glatiramer acetate, fingolimod, or natalizumab) is justified, whereas the switch to another interferon formulation will probably be of no benefit.

  2. Monoclonal antibodies directed against protoplasts of soybean cells : Generation of hybridomas and characterization of a monoclonal antibody reactive with the cell surface.

    Science.gov (United States)

    Villanueva, M A; Metcalf, T N; Wang, J L

    1986-09-01

    Splenocytes, derived from mice that had been immunized with protoplasts prepared from suspension cultures of root cells of Glycine max (L.) Merr. (SB-1 cell line), were fused with a murine myeloma cell line. The resulting hybridoma cultures were screened for the production of antibodies directed against the soybean protoplasts and were then cloned. One monoclonal antibody, designated MVS-1, was found to bind to the outer surface of the plasma membrane on the basis of several criteria: (a) agglutination of the protoplasts; (b) binding of fluorescence-labeled immunoglobulin on protoplasts yielding a ring staining pattern with prominent intensity at the edges; and (c) saturable binding by protoplasts of (125)I-labeled Antibody MVS-1. The antigenic target of Antibody MVS-1, identified by immunoblotting techniques, contained a polypeptide of relative molecular mass (Mr) approx. 400000 under both reducing and non-reducing conditions. When the antigenic target of Antibody MVS-1 was chromatographed in potassium phosphate buffer, the position of elution corresponded to that of a high-molecular-weight species (Mr 400000). These results provide the protein characterization required for the analysis of the mobility of Antibody MVS-1 bound to the plasma membrane of SB-1 cells.

  3. Antiviral Defense Mechanisms in Honey Bees

    Science.gov (United States)

    Brutscher, Laura M.; Daughenbaugh, Katie F.; Flenniken, Michelle L.

    2015-01-01

    Honey bees are significant pollinators of agricultural crops and other important plant species. High annual losses of honey bee colonies in North America and in some parts of Europe have profound ecological and economic implications. Colony losses have been attributed to multiple factors including RNA viruses, thus understanding bee antiviral defense mechanisms may result in the development of strategies that mitigate colony losses. Honey bee antiviral defense mechanisms include RNA-interference, pathogen-associated molecular pattern (PAMP) triggered signal transduction cascades, and reactive oxygen species generation. However, the relative importance of these and other pathways is largely uncharacterized. Herein we review the current understanding of honey bee antiviral defense mechanisms and suggest important avenues for future investigation. PMID:26273564

  4. JC virus antibody index in natalizumab-treated patients: correlations with John Cunningham virus DNA and C-reactive protein level

    Directory of Open Access Journals (Sweden)

    Lanzillo R

    2014-10-01

    Full Text Available Roberta Lanzillo,1 Raffaele Liuzzi,2 Luca Vallefuoco,3 Marcello Moccia,1 Luca Amato,1 Giovanni Vacca,1 Veria Vacchiano,1 Giuseppe Portella,3 Vincenzo Brescia Morra1 1Neurological Sciences Department, Federico II University, 2Institute of Biostructure and Bioimaging, National Research Council, 3Clinical Pathology Department, Federico II University, Naples, ItalyAbstract: Natalizumab-treated patients have a higher risk of developing progressive multifocal leukoencephalopathy. Exposure to John Cunningham virus (JCV is a prerequisite for PML (progressive multifocal leukoencephalopathy. To assess JCV exposure in multiple sclerosis patients, we performed a serological examination, obtained the antibody index, performed real-time polymerase chain reaction (PCR to detect JCV DNA in plasma and urine, and investigated the role of ultrasensitive C-reactive protein (usCRP as a possible biological marker of JCV reactivation. We retrospectively analyzed consecutive natalizumab-treated multiple sclerosis patients who underwent a JCV antibody test through a two-step enzyme-linked immunosorbent assay (STRATIFY test to the measure of serum usCRP levels, and to perform blood and urine JCV PCR. The studied cohort included 97 relapsing–remitting patients (60 women. Fifty-two patients (53.6% tested positive for anti-JCV antibodies. PCR showed JCV DNA in the urine of 30 out of 83 (36.1% patients and 28 out of 44 seropositive patients (63.6%, with a 6.7% false-negative rate for the STRATIFY test. Normalized optical density values were higher in urinary JCV DNA-positive patients (P<0.0001. Interestingly, the level of usCRP was higher in urinary JCV DNA-positive patients and correlated to the number of DNA copies in urine (P=0.028. As expected, patients' age correlated with JCV seropositivity and with JC viruria (P=0.02 and P=0.001, respectively. JC viruria was significantly correlated with a high JCV antibody index and high serum usCRP levels. We suggest that PCR and

  5. Rationally Designed Vaccines Targeting the V2 Region of HIV-1 gp120 Induce a Focused, Cross-Clade-Reactive, Biologically Functional Antibody Response.

    Science.gov (United States)

    Zolla-Pazner, Susan; Powell, Rebecca; Yahyaei, Sara; Williams, Constance; Jiang, Xunqing; Li, Wei; Lu, Shan; Wang, Shixia; Upadhyay, Chitra; Hioe, Catarina E; Totrov, Max; Kong, Xiangpeng

    2016-12-15

    Strong antibody (Ab) responses against V1V2 epitopes of the human immunodeficiency virus type 1 (HIV-1) gp120 envelope (Env) correlated with reduced infection rates in studies of HIV, simian-human immunodeficiency virus (SHIV), and simian immunodeficiency virus (SIV). In order to focus the Ab response on V1V2, we used six V1V2 sequences and nine scaffold proteins to construct immunogens which were tested using various immunization regimens for their ability to induce cross-reactive and biologically active V2 Abs in rabbits. A prime/boost immunization strategy was employed using gp120 DNA and various V1V2-scaffold proteins. The rabbit polyclonal Ab responses (i) were successfully focused on the V1V2 region, with weak or only transient responses to other Env epitopes, (ii) displayed broad cross-reactive binding activity with gp120s and the V1V2 regions of diverse strains from clades B, C, and E, (iii) included V2 Abs with specificities similar to those found in HIV-infected individuals, and (iv) remained detectable ≥1 year after the last boosting dose. Importantly, sera from rabbits receiving V1V2-scaffold immunogens displayed Ab-dependent cellular phagocytosis whereas sera from rabbits receiving only gp120 did not. The results represent the first fully successful example of reverse vaccinology in the HIV vaccine field with rationally designed epitope scaffold immunogens inducing Abs that recapitulate the epitope specificity and biologic activity of the human monoclonal Abs from which the immunogens were designed. Moreover, this is the first immunogenicity study using epitope-targeting, rationally designed vaccine constructs that induced an Fc-mediated activity associated with protection from infection with HIV, SIV, and SHIV. Novel immunogens were designed to focus the antibody response of rabbits on the V1V2 epitopes of HIV-1 gp120 since such antibodies were associated with reduced infection rates of HIV, SIV, and SHIV. The vaccine-induced antibodies were broadly

  6. Anti-influenza M2e antibody

    Science.gov (United States)

    Bradbury, Andrew M.

    2011-12-20

    Humanized recombinant and monoclonal antibodies specific for the ectodomain of the influenza virus M2 ion channel protein are disclosed. The antibodies of the invention have anti-viral activity and may be useful as anti-viral therapeutics and/or prophylactic/vaccine agents for inhibiting influenza virus replication and for treating individuals infected with influenza.

  7. Anti-influenza M2e antibody

    Energy Technology Data Exchange (ETDEWEB)

    Bradbury, Andrew M.

    2013-04-16

    Humanized recombinant and monoclonal antibodies specific for the ectodomain of the influenza virus M2 ion channel protein are disclosed. The antibodies of the invention have anti-viral activity and may be useful as anti-viral therapeutics and/or prophylactic/vaccine agents for inhibiting influenza virus replication and for treating individuals infected with influenza.

  8. Anti-influenza M2e antibody

    Science.gov (United States)

    Bradbury, Andrew M.

    2013-04-16

    Humanized recombinant and monoclonal antibodies specific for the ectodomain of the influenza virus M2 ion channel protein are disclosed. The antibodies of the invention have anti-viral activity and may be useful as anti-viral therapeutics and/or prophylactic/vaccine agents for inhibiting influenza virus replication and for treating individuals infected with influenza.

  9. Tyrosine-phosphorylated Ehrlichia chaffeensis and Ehrlichia canis tandem repeat orthologs contain a major continuous cross-reactive antibody epitope in lysine-rich repeats.

    Science.gov (United States)

    McBride, Jere W; Zhang, Xiaofeng; Wakeel, Abdul; Kuriakose, Jeeba A

    2011-08-01

    A small subset of major immunoreactive proteins have been identified in Ehrlichia chaffeensis and Ehrlichia canis, including three molecularly and immunologically characterized pairs of immunoreactive tandem repeat protein (TRP) orthologs with major continuous species-specific epitopes within acidic tandem repeats (TR) that stimulate strong antibody responses during infection. In this study, we identified a fourth major immunoreactive TR-containing ortholog pair and defined a major cross-reactive epitope in homologous nonidentical 24-amino-acid lysine-rich TRs. Antibodies from patients and dogs with ehrlichiosis reacted strongly with recombinant TR regions, and epitopes were mapped to the N-terminal TR region (18 amino acids) in E. chaffeensis and the complete TR (24 amino acids) in E. canis. Two less-dominant epitopes were mapped to adjacent glutamate/aspartate-rich and aspartate/tyrosine-rich regions in the acidic C terminus of E. canis TRP95 but not in E. chaffeensis TRP75. Major immunoreactive proteins in E. chaffeensis (75-kDa) and E. canis (95-kD) whole-cell lysates and supernatants were identified with TR-specific antibodies. Consistent with other ehrlichial TRPs, the TRPs identified in ehrlichial whole-cell lysates and the recombinant proteins migrated abnormally slow electrophoretically a characteristic that was demonstrated with the positively charged TR and negatively charged C-terminal domains. E. chaffeensis TRP75 and E. canis TRP95 were immunoprecipitated with anti-pTyr antibody, demonstrating that they are tyrosine phosphorylated during infection of the host cell.

  10. Epitope predictions indicate the presence of two distinct types of epitope-antibody-reactivities determined by epitope profiling of intravenous immunoglobulins.

    Directory of Open Access Journals (Sweden)

    Mitja Luštrek

    Full Text Available Epitope-antibody-reactivities (EAR of intravenous immunoglobulins (IVIGs determined for 75,534 peptides by microarray analysis demonstrate that roughly 9% of peptides derived from 870 different human protein sequences react with antibodies present in IVIG. Computational prediction of linear B cell epitopes was conducted using machine learning with an ensemble of classifiers in combination with position weight matrix (PWM analysis. Machine learning slightly outperformed PWM with area under the curve (AUC of 0.884 vs. 0.849. Two different types of epitope-antibody recognition-modes (Type I EAR and Type II EAR were found. Peptides of Type I EAR are high in tyrosine, tryptophan and phenylalanine, and low in asparagine, glutamine and glutamic acid residues, whereas for peptides of Type II EAR it is the other way around. Representative crystal structures present in the Protein Data Bank (PDB of Type I EAR are PDB 1TZI and PDB 2DD8, while PDB 2FD6 and 2J4W are typical for Type II EAR. Type I EAR peptides share predicted propensities for being presented by MHC class I and class II complexes. The latter interaction possibly favors T cell-dependent antibody responses including IgG class switching. Peptides of Type II EAR are predicted not to be preferentially presented by MHC complexes, thus implying the involvement of T cell-independent IgG class switch mechanisms. The high extent of IgG immunoglobulin reactivity with human peptides implies that circulating IgG molecules are prone to bind to human protein/peptide structures under non-pathological, non-inflammatory conditions. A webserver for predicting EAR of peptide sequences is available at www.sysmed-immun.eu/EAR.

  11. Serum Reactivity Against Bacterial Pyruvate Dehydrogenase: Increasing the Specificity of Anti-Mitochondrial Antibodies for the Diagnosis of Primary Biliary Cirrhosis

    Directory of Open Access Journals (Sweden)

    Hiroshi Miyakawa

    2006-01-01

    Full Text Available Antimitochondrial antibodies (AMA are the serum hallmark of primary biliary cirrhosis (PBC. However, AMA-positivity can be found in non-PBC sera when lower dilutions are used, thus raising issues about the specificity and sensitivity of the test. AMA reacts primarily with the lipoylated domains of pyruvate dehydrogenase-E2 (PDC-E2 which is highly conserved across species, including bacteria. We studied 77 serum samples, including 24 from patients with anti-PDC-E2-positive PBC and 53 controls (16 with autoimmune hepatitis (AIH, 10 with primary sclerosing cholangitis (PSC, and 27 healthy individuals for their reactivities at serial dilutions (1:10, 1:20 and 1:40 against Escherichia coli DH5 alpha lysate overexpressing human PDC-E2 using immunoblotting (IB. A murine anti-human PDC-E2 monoclonal antibody (mAB was used as control. We further studied positive sera using adsorption with a synthetic E. coli peptide sharing similarity with human PDC-E2. Finally, we verified whether a unique buffer for E. coli preparation could reduce non-specific serum reactivity. Results demonstrated that 100% of anti-PDC-E2-positive PBC and up to 38% of control sera at 1:10 dilution recognized E. coli PDC-E2 at IB while dilution tests indicated that the overall potency of PBC reactivity was 100-fold higher compared to controls. In fact, a subgroup (20-38% of non-PBC sera were positive at low titers but lost the reactivity when absorbed with the synthetic E. coli peptide. Finally, our unique buffer reduced the reactivity of non-PBC sera as measured by ELISA. In conclusion, we demonstrated that weak cross-reactivity with E. coli PDC-E2 occurs in non-PBC sera at lower dilutions and that such reactivity is not due to AMA-positivity. The use of a specific buffer might avoid the risk of false positive AMA determinations when E. coli-expressed recombinant antigens are used.

  12. Three monoclonal antibodies to the VHS virus glycoprotein: comparison of reactivity in relation to differences in immunoglobulin variable domain gene sequences

    DEFF Research Database (Denmark)

    Lorenzen, Niels; Cupit, P.M.; Secombes, C.J.;

    2000-01-01

    Three monoclonal antibodies (MAbs) to the VHSV G protein were compared in different immunoassays and the variable domain cDNA sequences from the respective immunoglobulin (Ig) genes were determined. One MAb (IP1H3) was non-neutralising and recognised different virus isolates equally well in ELISA...... originated from the same virgin B lymphocyte. The few differences observed in the VH and V kappa amino acid sequences were probably due to somatic mutations arising during affinity maturation and might explain the observed reactivity differences between the two MAbs....

  13. Association of cross-reactive antibodies targeting peptidyl-arginine deiminase 3 and 4 with rheumatoid arthritis-associated interstitial lung disease.

    Directory of Open Access Journals (Sweden)

    Jon T Giles

    Full Text Available BACKGROUND: A subset of rheumatoid arthritis (RA patients have detectable antibodies directed against the peptidyl-arginine deiminase (PAD enzyme isoforms 3 and 4. Anti-PAD3/4 cross-reactive antibodies (anti-PAD3/4XR have been shown to lower the calcium threshold required for PAD4 activation, an effect potentially relevant to the pathogenesis of RA-associated interstitial lung disease (ILD. METHODS: RA patients underwent multi-detector computed tomography (MDCT of the chest with interpretation by a pulmonary radiologist for ILD features. A semi-quantitative ILD Score (range 0-32 was calculated. Concurrent serum samples were assessed for antibodies against PAD by immunoprecipitation with radiolabeled PAD3 and PAD4. RESULTS: Among the 176 RA patients studied, any ILD was observed in 58 (33% and anti-PAD3/4XR was detected in 19 (11%. The frequency of any ILD among those with anti-PAD3/4XR was 68% vs. 29% among those with no anti-PAD (crude OR = 5.39; p = 0.002 and vs. 27% among those with anti-PAD4 that was not cross-reactive with PAD3 (crude OR = 5.74; p = 0.001. Both associations were stronger after adjustment for relevant confounders (adjusted ORs = 7.22 and 6.61, respectively; both p-values<0.01. Among ever smokers with anti-PAD3/4XR, the adjusted frequency of any ILD was 93% vs. 17% for never smokers without the antibody (adjusted OR = 61.4; p = 0.001, p-value for the interaction of smoking with anti-PAD3/4XR<0.05. CONCLUSIONS: The prevalence and extent of ILD was markedly higher among RA patients with anti-PAD3/4 cross-reactive antibodies, even after accounting for relevant confounders, particularly among ever smokers. These findings may suggest etiopathologic mechanisms of RA-ILD, and their clinical utility for predicting ILD warrants additional study.

  14. Detection of antibodies to hepatitis B core antigen using the Abbott ARCHITECT anti-HBc assay: analysis of borderline reactive sera.

    Science.gov (United States)

    Ollier, Laurence; Laffont, Catherine; Kechkekian, Aurore; Doglio, Alain; Giordanengo, Valérie

    2008-12-01

    Routine use of the automated chemiluminescent microparticle immunoassay Abbott ARCHITECT anti-HBc for diagnosis of hepatitis B is limited in case of borderline reactive sera with low signal close to the cut-off index. In order to determine the significance of anti-HBc detection when borderline reactivity occurs using the ARCHITECT anti-HBc assay, a comparative study was designed. 3540 serum samples collected over a 2-month period in the hospital of Nice were examined for markers of HBV infection (HBsAg, anti-HBs and anti-HBc). One hundred seven samples with sufficient volume and with borderline reactivity by the ARCHITECT assay were tested by two other anti-HBc assays, a microparticle enzyme immunoassay (MEIA, AxSYM Core, Abbott Laboratories, IL, USA) and an enzyme linked fluorescent assay (ELFA, VIDAS Anti-HBc Total II, bioMérieux, Lyon, France). Only 46 samples were confirmed by the AxSYM and the VIDAS assays. Additional serological information linked to patient history showed that the remaining samples (61) were false positives (11), had low titer of anti-HBc antibodies (13), or were inconclusive (37). This comparative study highlighted the existence of a grey zone around the cut-off index. Confirmative results through a different immunoassay are needed to confirm the diagnosis of HBV on borderline reactive sera using the ARCHITECT anti-HBc assay.

  15. Elevated stress hormone levels relate to Epstein-Barr virus reactivation in astronauts

    Science.gov (United States)

    Stowe, R. P.; Pierson, D. L.; Barrett, A. D.

    2001-01-01

    OBJECTIVE: The objective of this study was to determine the effects of stress and spaceflight on levels of neuroendocrine hormones and Epstein-Barr virus (EBV)-specific antibodies in astronauts. METHODS: Antiviral antibody titers and stress hormones were measured in plasma samples collected from 28 astronauts at their annual medical exam (baseline), 10 days before launch (L-10), landing day (R+0), and 3 days after landing (R+3). Urinary stress hormones were also measured at L-10 and R+0. RESULTS: Significant increases (p stresses associated with spaceflight resulted in decreased virus-specific T-cell immunity and reactivation of EBV.

  16. Humoral Immunity to Commensal Oral Bacteria in Human Infants: Salivary Secretory Immunoglobulin A Antibodies Reactive with Streptococcus mitis biovar 1, Streptococcus oralis, Streptococcus mutans, and Enterococcus faecalis during the First Two Years of Life

    Science.gov (United States)

    Cole, Michael F.; Bryan, Stacey; Evans, Mishell K.; Pearce, Cheryl L.; Sheridan, Michael J.; Sura, Patricia A.; Wientzen, Raoul L.; Bowden, George H. W.

    1999-01-01

    Secretory immunoglobulin A (SIgA) antibodies reactive with the pioneer oral streptococci Streptococcus mitis biovar 1 and Streptococcus oralis, the late oral colonizer Streptococcus mutans, and the pioneer enteric bacterium Enterococcus faecalis in saliva samples from 10 human infants from birth to age 2 years were analyzed. Low levels of salivary SIgA1 and SIgA2 antibodies reactive with whole cells of all four species were detected within the first month after birth, even though S. mutans and E. faecalis were not recovered from the mouths of the infants during the study period. Although there was a fivefold increase in the concentration of SIgA between birth and age 2 years, there were no differences between the concentrations of SIgA1 and SIgA2 antibodies reactive with the four species over this time period. When the concentrations of SIgA1 and SIgA2 antibodies reactive with all four species were normalized to the concentrations of SIgA1 and SIgA2 in saliva, SIgA1 and SIgA2 antibodies reactive with these bacteria showed a significant decrease from birth to 2 years of age. Adsorption of each infant’s saliva with cells of one species produced a dramatic reduction of antibodies recognizing the other three species. Sequential adsorption of saliva samples removed all SIgA antibody to the bacteria, indicating that the SIgA antibodies were directed to antigens shared by all four species. The induction by the host of a limited immune response to common antigens that are likely not involved in adherence may be among the mechanisms that commensal streptococci employ to persist in the oral cavity. PMID:10085031

  17. The Use of Chimeric Virus-like Particles Harbouring a Segment of Hantavirus Gc Glycoprotein to Generate a Broadly-Reactive Hantavirus-Specific Monoclonal Antibody

    Directory of Open Access Journals (Sweden)

    Aurelija Zvirbliene

    2014-02-01

    Full Text Available Monoclonal antibodies (MAbs against viral glycoproteins have important diagnostic and therapeutic applications. In most cases, the MAbs specific to viral glycoproteins are raised against intact virus particles. The biosynthesis of viral glycoproteins in heterologous expression systems such as bacteria, yeast, insect or mammalian cells is often problematic due to their low expression level, improper folding and limited stability. To generate MAbs against hantavirus glycoprotein Gc, we have used initially a recombinant yeast-expressed full-length Puumala virus (PUUV Gc protein. However, this approach was unsuccessful. As an alternative recombinant antigen, chimeric virus-like particles (VLPs harboring a segment of PUUV Gc glycoprotein were generated in yeast Saccharomyces cerevisiae. A 99 amino acid (aa-long segment of Gc protein was inserted into the major capsid protein VP1 of hamster polyomavirus at previously defined positions: either site #1 (aa 80–89 or site #4 (aa 280–289. The chimeric proteins were found to self-assemble to VLPs as evidenced by electron microscopy. Chimeric VLPs induced an efficient insert-specific antibody response in immunized mice. Monoclonal antibody (clone #10B8 of IgG isotype specific to hantavirus Gc glycoprotein was generated. It recognized recombinant full-length PUUV Gc glycoprotein both in ELISA and Western blot assay and reacted specifically with hantavirus-infected cells in immunofluorescence assay. Epitope mapping studies revealed the N-terminally located epitope highly conserved among different hantavirus strains. In conclusion, our approach to use chimeric VLPs was proven useful for the generation of virus-reactive MAb against hantavirus Gc glycoprotein. The generated broadly-reactive MAb #10B8 might be useful for various diagnostic applications.

  18. Antithyroglobulin antibody

    Science.gov (United States)

    Thyroglobulin antibody; Thyroiditis - thyroglobulin antibody; Hypothyroidism - thyroglobulin antibody; Thyroiditis - thyroglobulin antibody; Graves disease - thyroglobulin antibody; Underactive thyroid - thyroglobulin antibody

  19. High Concentrations of Angiopoietin-Like Protein 4 Detected in Serum from Patients with Rheumatoid Arthritis Can Be Explained by Non-Specific Antibody Reactivity

    Science.gov (United States)

    Makoveichuk, Elena; Ruge, Toralph; Nilsson, Solveig; Södergren, Anna

    2017-01-01

    Angiopoietin-like protein 4 (ANGPTL4) is suggested to be a master regulator of plasma triglyceride metabolism. Our aim was to study whether the previously reported high levels of ANGPTL4 detected in serum from patients with rheumatoid arthritis (RA) by ELISA was due to any specific molecular form of this protein (oligomers, monomers or fragments). ANGPTL4 levels were first determined in serum from 68 RA patients and 43 age and sex matched control subjects and the mean values differed by a factor of 5.0. Then, ANGPTL4 was analyzed after size exclusion chromatography (SEC) of serum samples. With serum from one of the RA patients with high levels of ANGPTL4, the dominant reactivity was found in fractions corresponding to high-molecular weight proteins. In addition, a minor peak of reactivity eluting late from the column was found both in the patient and in controls. By the use of HeteroBlock®, and by careful selection of antibodies, we documented non-specific reactions for ANGPTL4 in 39% of samples from the RA patients, most likely due to cross-reactivity of the antibodies with rheumatoid factor (RF). The corresponding figure for control subjects was 6.3%. After corrections for non-specific reactions, the mean level of ANGPTL4 in serum from RA patients was still significantly higher than in control individuals (mean levels were 101±62 and 67±39 ng/ml respectively, P = 0.02). We re-analyzed samples from our previously published studies on ANGPL4 levels in patients on hemodialysis and patients with diabetes type 2. These samples did not show false positive reactions. The levels of ANGPTL4 were comparable to those detected previously. PMID:28107351

  20. Periodontitis prevalence and serum antibody reactivity to periodontal bacteria in primary Sjögren's syndrome: a pilot study.

    Science.gov (United States)

    Lugonja, Bozo; Yeo, Lorraine; Milward, Michael R; Smith, Diana; Dietrich, Thomas; Chapple, Iain L C; Rauz, Saaeha; Williams, Geraint P; Barone, Francesca; de Pablo, Paola; Buckley, Chris; Hamburger, John; Richards, Andrea; Poveda-Gallego, Ana; Scheel-Toellner, Dagmar; Bowman, Simon J

    2016-01-01

    The aims of this study were as follows: (i) To assess the prevalence of periodontitis among patients with primary Sjögren's syndrome (pSS) and comparator groups of patients with rheumatoid arthritis (RA) and osteoarthritis (OA). (ii) To perform a pilot study to compare serum antibody responses to 10 oral/periodontal bacteria in these patient groups and a historical comparator group of patients with periodontitis. Standard clinical periodontal assessments were performed on 39 pSS, 36 RA and 23 OA patients and "In-house" antibody ELISAs for serum antibodies against 10 oral/periodontal bacteria were performed in these groups. Forty-six percent of the pSS group, 64% of the RA group and 48% of the OA group had moderate/severe periodontitis. These frequencies did not reach statistical significance between groups. Raised antibody levels to Prevotella denticola were found in the pSS, RA and periodontitis groups compared to the OA group. Significant between group differences were seen for Aggregatibacter actinomycetemcomitans, Prevotella intermedia and Campylobacter showae. None of these differences were specifically associated with pSS. This study showed no increase in periodontitis in pSS patients. Although the P. denticola data are of interest, identifying bacterial triggering factors for pSS will likely require alternative strategies including modern techniques such as microbiome analysis. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Cross-Reactive Human IgM-Derived Monoclonal Antibodies that Bind to HIV-1 Envelope Glycoproteins

    Directory of Open Access Journals (Sweden)

    Barton F. Haynes

    2010-02-01

    Full Text Available Elicitation of antibodies with potent and broad neutralizing activity against HIV by immunization remains a challenge. Several monoclonal antibodies (mAbs isolated from humans with HIV-1 infection exhibit such activity but vaccine immunogens based on structures containing their epitopes have not been successful for their elicitation. All known broadly neutralizing mAbs (bnmAbs are immunoglobulin (Ig Gs (IgGs and highly somatically hypermutated which could impede their elicitation. Ig Ms (IgMs are on average significantly less divergent from germline antibodies and are relevant for the development of vaccine immunogens but are underexplored compared to IgGs. Here we describe the identification and characterization of several human IgM-derived mAbs against HIV-1 which were selected from a large phage-displayed naive human antibody library constructed from blood, lymph nodes and spleens of 59 healthy donors. These antibodies bound with high affinity to recombinant envelope glycoproteins (gp140s, Envs of HIV-1 isolates from different clades. They enhanced or did not neutralize infection by some of the HIV-1 primary isolates using CCR5 as a coreceptor but neutralized all CXCR4 isolates tested although weakly. One of these antibodies with relatively low degree of somatic hypermutation was more extensively characterized. It bound to a highly conserved region partially overlapping with the coreceptor binding site and close to but not overlapping with the CD4 binding site. These results suggest the existence of conserved structures that could direct the immune response to non-neutralizing or even enhancing antibodies which may represent a strategy used by the virus to escape neutralizing immune responses. Further studies will show whether such a strategy plays a role in HIV infection of humans, how important that role could be, and what the mechanisms of infection enhancement are. The newly identified mAbs could be used as reagents to further

  2. Duodenal enteroglucagonoma revealed by differential comparison of serum and tissue glucagon reactivity with Siemens' Double Glucagon Antibody and DakoCytomation's Polyclonal Rabbit Anti-Human Glucagon: a case report

    Directory of Open Access Journals (Sweden)

    Abouljoud Marwan S

    2010-06-01

    Full Text Available Abstract Introduction This case report demonstrates that the differential immunohistochemical reactivities of Siemens' Double Antibody Glucagon compared to DakoCytomation's Polyclonal Rabbit Anti-Human Glucagon allow for pathologic distinction of enteral versus pancreatic glucagonoma. Case presentation A 64-year-old Caucasian man was diagnosed with a duodenal enteroglucagonoma following presentation with obstructive jaundice. He had a low serum glucagon level using Siemens' Double Antibody Glucagon, a clinical syndrome consistent with glucagon hypersecretion. A periampullary mass biopsy proved to be a neuroendocrine tumor, with positive immunohistochemical reactivity to DakoCytomation's Polyclonal Rabbit Anti-Human Glucagon. Conclusions Differential comparison of the immunohistochemical reactivities of Siemens' Double Antibody Glucagon and DakoCytomation's Polyclonal Rabbit Anti-Human Glucagon discerns enteroglucagon from pancreatic glucagon.

  3. Effect of linker length between variable domains of single chain variable fragment antibody against daidzin on its reactivity.

    Science.gov (United States)

    Yusakul, Gorawit; Sakamoto, Seiichi; Pongkitwitoon, Benyakan; Tanaka, Hiroyuki; Morimoto, Satoshi

    2016-07-01

    The peptide linker between variable domains of heavy (VH) and light (VL) chains is one of important factors that influence the characteristics of scFv, including binding activity and specificity against target antigen. The scFvs against daidzin (DZ-scFvs) with different linker lengths were constructed in the format of VH-(GGGGS)n-VL (n = 1, 3, 5, and 7). They were expressed in the hemolymph of silkworm larvae using the Bombyx mori nucleopolyhedrovirus (BmNPV) bacmid DNA system, and their reactivity against daidzin and related compounds were evaluated using an indirect competitive enzyme-linked immunosorbent assay (icELISA), which is applicable for quantitative analysis of daidzin. The results showed that the reactivity of scFvs against daidzin was increased, whereas specificity slightly decreased when their peptide linker was lengthened. These results suggested that the linker length of DZ-scFvs contributes to its reactivity. In addition, the results emphasize that the linker length could control the reactivity of DZ-scFvs.

  4. Guillain-Barré syndrome-related Campylobacter jejuni in Bangladesh: Ganglioside mimicry and cross-reactive antibodies

    NARCIS (Netherlands)

    Z. Islam (Zhahirul); M. Gilbert (Michel); Q.D. Mohammad (Quazi); K. Klaij (Kevin); J. Li (Jianjun); W. van Rijs (Wouter); A.P. Tio-Gillen (Anne); K.A. Talukder (Kaisar); H.J. Willison (Hugh); A.F. van Belkum (Alex); H.P. Endtz (Hubert); B.C. Jacobs (Bart)

    2012-01-01

    textabstractBackground: Campylobacter jejuni is the predominant antecedent infection in Guillain-Barré syndrome (GBS). Molecular mimicry and cross-reactive immune responses to C. jejuni lipo-oligosaccharides (LOS) precipitate the development of GBS, although this mechanism has not been established

  5. Guillain-Barre Syndrome-Related Campylobacter jejuni in Bangladesh : Ganglioside Mimicry and Cross-Reactive Antibodies

    NARCIS (Netherlands)

    Islam, Zhahirul; Gilbert, Michel; Mohammad, Quazi D.; Klaij, Kevin; Li, Jianjun; van Rijs, Wouter; Tio-Gillen, Anne P.; Talukder, Kaisar A.; Willison, Hugh J.; van Belkum, Alex; Endtz, Hubert P.; Jacobs, Bart C.

    2012-01-01

    Background: Campylobacter jejuni is the predominant antecedent infection in Guillain-Barre syndrome (GBS). Molecular mimicry and cross-reactive immune responses to C. jejuni lipo-oligosaccharides (LOS) precipitate the development of GBS, although this mechanism has not been established in patients f

  6. Guillain-Barré syndrome-related Campylobacter jejuni in Bangladesh: Ganglioside mimicry and cross-reactive antibodies

    NARCIS (Netherlands)

    Z. Islam (Zhahirul); M. Gilbert (Michel); Q.D. Mohammad (Quazi); K. Klaij (Kevin); J. Li (Jianjun); W. van Rijs (Wouter); A.P. Tio-Gillen (Anne); K.A. Talukder (Kaisar); H.J. Willison (Hugh); A.F. van Belkum (Alex); H.P. Endtz (Hubert); B.C. Jacobs (Bart)

    2012-01-01

    textabstractBackground: Campylobacter jejuni is the predominant antecedent infection in Guillain-Barré syndrome (GBS). Molecular mimicry and cross-reactive immune responses to C. jejuni lipo-oligosaccharides (LOS) precipitate the development of GBS, although this mechanism has not been established i

  7. Ophthalmic antiviral chemotherapy : An overview

    Directory of Open Access Journals (Sweden)

    Athmanathan Sreedharan

    1997-01-01

    Full Text Available Antiviral drug development has been slow due to many factors. One such factor is the difficulty to block the viral replication in the cell without adversely affecting the host cell metabolic activity. Most of the antiviral compounds are analogs of purines and pyramidines. Currently available antiviral drugs mainly inhibit viral nucleic acid synthesis, hence act only on actively replicating viruses. This article presents an overview of some of the commonly used antiviral agents in clinical ophthalmology.

  8. Intravenous immunoglobulin prevents murine antibody-mediated acute lung injury at the level of neutrophil reactive oxygen species (ROS production.

    Directory of Open Access Journals (Sweden)

    John W Semple

    Full Text Available Transfusion-related acute lung injury (TRALI is a leading cause of transfusion-associated mortality that can occur with any type of transfusion and is thought to be primarily due to donor antibodies activating pulmonary neutrophils in recipients. Recently, a large prospective case controlled clinical study of cardiac surgery patients demonstrated that despite implementation of male donors, a high incidence of TRALI still occurred and suggested a need for additional interventions in susceptible patient populations. To examine if intravenous immunoglobulin (IVIg may be effective, a murine model of antibody-mediated acute lung injury that approximates human TRALI was examined. When BALB/c mice were injected with the anti-major histocompatibility complex class I antibody 34-1-2s, mild shock (reduced rectal temperature and respiratory distress (dyspnea were observed and pre-treatment of the mice with 2 g/kg IVIg completely prevented these symptoms. To determine IVIg's usefulness to affect severe lung damage, SCID mice, previously shown to be hypersensitive to 34-1-2s were used. SCID mice treated with 34-1-2s underwent severe shock, lung damage (increased wet/dry ratios and 40% mortality within 2 hours. Treatment with 2 g/kg IVIg 18 hours before 34-1-2s administration completely protected the mice from all adverse events. Treatment with IVIg after symptoms began also reduced lung damage and mortality. While the prophylactic IVIg administration did not affect 34-1-2s-induced pulmonary neutrophil accumulation, bone marrow-derived neutrophils from the IVIg-treated mice displayed no spontaneous ROS production nor could they be stimulated in vitro with fMLP or 34-1-2s. These results suggest that IVIg prevents murine antibody-mediated acute lung injury at the level of neutrophil ROS production and thus, alleviating tissue damage.

  9. Antiviral Drugs: Seasonal Flu

    Centers for Disease Control (CDC) Podcasts

    2010-09-29

    In this podcast, Dr. Joe Bresee explains the nature of antiviral drugs and how they are used for seasonal flu.  Created: 9/29/2010 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 9/29/2010.

  10. Structural analysis of a dengue cross-reactive antibody complexed with envelope domain III reveals the molecular basis of cross-reactivity.

    Science.gov (United States)

    Midgley, Claire M; Flanagan, Aleksandra; Tran, Hai Bac; Dejnirattisai, Wanwisa; Chawansuntati, Kriangkrai; Jumnainsong, Amonrat; Wongwiwat, Wiyada; Duangchinda, Thaneeya; Mongkolsapaya, Juthathip; Grimes, Jonathan M; Screaton, Gavin R

    2012-05-15

    Dengue virus infections are still increasing at an alarming rate in tropical and subtropical countries, underlying the need for a dengue vaccine. Although it is relatively easy to generate Ab responses to dengue virus, low avidity or low concentrations of Ab may enhance infection of FcR-bearing cells with clinical impact, posing a challenge to vaccine production. In this article, we report the characterization of a mAb, 2H12, which is cross-reactive to all four serotypes in the dengue virus group. Crystal structures of 2H12-Fab in complex with domain III of the envelope protein from three dengue serotypes have been determined. 2H12 binds to the highly conserved AB loop of domain III of the envelope protein that is poorly accessible in the mature virion. 2H12 neutralization varied between dengue serotypes and strains; in particular, dengue serotype 2 was not neutralized. Because the 2H12-binding epitope was conserved, this variation in neutralization highlights differences between dengue serotypes and suggests that significant conformational changes in the virus must take place for Ab binding. Surprisingly, 2H12 facilitated little or no enhancement of infection. These data provide a structural basis for understanding Ab neutralization and enhancement of infection, which is crucial for the development of future dengue vaccines.

  11. A Cross-Reactive Human Single-Chain Antibody for Detection of Major Fish Allergens, Parvalbumins, and Identification of a Major IgE-Binding Epitope.

    Directory of Open Access Journals (Sweden)

    Merima Bublin

    Full Text Available Fish allergy is associated with moderate to severe IgE-mediated reactions to the calcium binding parvalbumins present in fish muscle. Allergy to multiple fish species is caused by parvalbumin-specific cross-reactive IgE recognizing conserved epitopes. In this study, we aimed to produce cross-reactive single chain variable fragment (scFv antibodies for the detection of parvalbumins in fish extracts and the identification of IgE epitopes. Parvalbumin-specific phage clones were isolated from the human ETH-2 phage display library by three rounds of biopanning either against cod parvalbumin or by sequential biopanning against cod (Gad m 1, carp (Cyp c 1 and rainbow trout (Onc m 1 parvalbumins. While biopanning against Gad m 1 resulted in the selection of clones specific exclusively for Gad m 1, the second approach resulted in the selection of clones cross-reacting with all three parvalbumins. Two clones, scFv-gco9 recognizing all three parvalbumins, and scFv-goo8 recognizing only Gad m 1 were expressed in the E. coli non-suppressor strain HB2151 and purified from the periplasm. scFv-gco9 showed highly selective binding to parvalbumins in processed fish products such as breaded cod sticks, fried carp and smoked trout in Western blots. In addition, the scFv-gco9-AP produced as alkaline phosphatase fusion protein, allowed a single-step detection of the parvalbumins. In competitive ELISA, scFv-gco9 was able to inhibit binding of IgE from fish allergic patients' sera to all three β-parvalbumins by up to 80%, whereas inhibition by scFv-goo8 was up to 20%. 1H/15N HSQC NMR analysis of the rGad m 1:scFv-gco9 complex showed participation of amino acid residues conserved among these three parvalbumins explaining their cross-reactivity on a molecular level. In this study, we have demonstrated an approach for the selection of cross-reactive parvalbumin-specific antibodies that can be used for allergen detection and for mapping of conserved epitopes.

  12. Sensitization prevalence, antibody cross-reactivity and immunogenic peptide profile of Api g 2, the non-specific lipid transfer protein 1 of celery.

    Directory of Open Access Journals (Sweden)

    Gabriele Gadermaier

    Full Text Available BACKGROUND: Celery (Apium graveolens represents a relevant allergen source that can elicit severe reactions in the adult population. To investigate the sensitization prevalence and cross-reactivity of Api g 2 from celery stalks in a Mediterranean population and in a mouse model. METHODOLOGY: 786 non-randomized subjects from Italy were screened for IgE reactivity to rApi g 2, rArt v 3 (mugwort pollen LTP and nPru p 3 (peach LTP using an allergen microarray. Clinical data of 32 selected patients with reactivity to LTP under investigation were evaluated. Specific IgE titers and cross-inhibitions were performed in ELISA and allergen microarray. Balb/c mice were immunized with purified LTPs; IgG titers were determined in ELISA and mediator release was examined using RBL-2H3 cells. Simulated endolysosomal digestion was performed using microsomes obtained from human DCs. RESULTS: IgE testing showed a sensitization prevalence of 25.6% to Api g 2, 18.6% to Art v 3, and 28.6% to Pru p 3 and frequent co-sensitization and correlating IgE-reactivity was observed. 10/32 patients suffering from LTP-related allergy reported symptoms upon consumption of celery stalks which mainly presented as OAS. Considerable IgE cross-reactivity was observed between Api g 2, Art v 3, and Pru p 3 with varying inhibition degrees of individual patients' sera. Simulating LTP mono-sensitization in a mouse model showed development of more congruent antibody specificities between Api g 2 and Art v 3. Notably, biologically relevant murine IgE cross-reactivity was restricted to the latter and diverse from Pru p 3 epitopes. Endolysosomal processing of LTP showed generation of similar clusters, which presumably represent T-cell peptides. CONCLUSIONS: Api g 2 represents a relevant celery stalk allergen in the LTP-sensitized population. The molecule displays common B cell epitopes and endolysosomal peptides that encompass T cell epitopes with pollen and plant-food derived LTP.

  13. Checkpoint inhibitors in cancer immunotherapy: Cross reactivity of a CTLA-4 antibody and IDO-inhibitor L-1MT in pigs

    DEFF Research Database (Denmark)

    Al-Shatrawi, Zina Adil; Frøsig, Thomas Mørch; Jungersen, Gregers

    a non-specific activation of porcine T cells. This will be further investigated to provide the basis for in vivo studies investigating checkpoint inhibitor blockade in combination with other cancer immunotherapies. Eventually our goal is to establish pigs as an alternative large animal model......Blockade of checkpoint inhibitors has recently shown very convincing results in the treatment of cancer. One key target is CTLA-4, which has been demonstrated to be a potent negative regulator of lymphocyte activation. The treatment with the FDA-approved fully human CTLA-4 monoclonal antibody...... Ipilimumab increases anticancer T-cell reactivity and overall survival of metastatic cancer patients. Indole-amine 2,3-dioxygenase (IDO) is another checkpoint inhibitor which suppresses T-cell immunity by the depletion of tryptophan in the T-cell microenvironment, and also inhibition of IDO by L-1...

  14. Cross-reactivity of antibodies against leptospiral recurrent uveitis-associated proteins A and B (LruA and LruB with eye proteins.

    Directory of Open Access Journals (Sweden)

    Ashutosh Verma

    2010-08-01

    Full Text Available Infection by Leptospira interrogans has been causally associated with human and equine uveitis. Studies in our laboratories have demonstrated that leptospiral lipoprotein LruA and LruB are expressed in the eyes of uveitic horses, and that antibodies directed against LruA and LruB react with equine lenticular and retinal extracts, respectively. These reactivities were investigated further by performing immunofluorescent assays on lenticular and retinal tissue sections. Incubation of lens tissue sections with LruA-antiserum and retinal sections with LruB-antiserum resulted in positive fluorescence. By employing two-dimensional gel analyses followed by immunoblotting and mass spectrometry, lens proteins cross-reacting with LruA antiserum were identified to be alpha-crystallin B and vimentin. Similarly, mass spectrometric analyses identified beta-crystallin B2 as the retinal protein cross-reacting with LruB-antiserum. Purified recombinant human alpha-crystallin B and vimentin were recognized by LruA-directed antiserum, but not by control pre-immune serum. Recombinant beta-crystallin B2 was likewise recognized by LruB-directed antiserum, but not by pre-immune serum. Moreover, uveitic eye fluids contained significantly higher levels of antiibodies that recognized alpha-crystallin B, beta-crystallin B2 and vimentin than did normal eye fluids. Our results indicate that LruA and LruB share immuno-relevant epitopes with eye proteins, suggesting that cross-reactive antibody interactions with eye antigens may contribute to immunopathogenesis of Leptospira-associated recurrent uveitis.

  15. Hantaan/Andes virus DNA Vaccine Elicits a Broadly Cross-Reactive Neutralizing Antibody Response in Nonhuman Primates

    Science.gov (United States)

    2006-01-01

    cells, and antibodies HTNV, strain 76–118 (Lee et al., 1978), SEOV, strain SR-ll (Kitamura et al., 1983), DOBV (Avsic- Zupanc et al., 1992), PUUV...National Research Council Research Associateship Award at USAM- RIID. References Avsic- Zupanc , T., Xiao, S.Y., Stojanovic, R., Gligic, A., van der...glycoproteins G1 and G2. Virology 331, 307–315. Elgh, F., Lundkvist, A., Alexeyev, O.A., Stenlund, H., Avsic- Zupanc , T., Hjelle, B., Lee, H.W., Smith

  16. Immunization of mice by a multimeric L2-based linear epitope (17-36) from HPV type 16/18 induced cross reactive neutralizing antibodies.

    Science.gov (United States)

    Khiavi, Farhad Motavalli; Arashkia, Arash; Nasimi, Maryam; Mahdavi, Mehdi; Golkar, Majid; Roohvand, Farzin; Azadmanesh, Kayhan

    2017-08-01

    Current licensed and commercially available prophylactic human papillomavirus (HPV) vaccines (Cervarix and quadrivalent/nine valents Gardasil) are based on major capsid protein L1 virus-like particles (VLPs) production which are expensive and type specific. Minor capsid L2-RG1 linear epitope (17-36) is a known candidate for induction of cross-neutralizing antibodies to develop low-cost pan-HPV vaccines. Herein, we report construction and expression of a three tandem repeats of L2-RG1 derived from HPV16 and 18 fused with the same head to tail pattern (HPV16:17-36×3+ HPV18:17-36×3; hereafter termed dual-type fusion L2 peptide) in E. coli and provide the results of its immunogenicity in mice. SDS-PAGE and western blot analyses indicated proper expression of the peptide that could be further purified by Ni-NTA affinity chromatography via the located C-terminal 6xHis-tag. Mice immunized by formulation of the purified peptide and Freund adjuvant raised neutralizing antibodies which showed proper cross reactivity to HPV L2 (11-200) of types: 18, 16, 31 and 45 (which totally are responsible for 90% of cervical cancers) and efficiently neutralized HPV18/16 pseudoviruses in vitro. Our results imply the possibility of development of a simple, low-cost preventive HPV vaccine based on this dual-type fusion L2 peptide in bacterial expression system with broad spectrum.

  17. Antibody ligation of CM1 on cisplatin-exposed HeLa cells induces apoptosis through reactive oxygen species-dependent Fas ligand expression.

    Science.gov (United States)

    Park, Ga Bin; Kim, Daejin; Yoon, Hoi Soo; Kim, Yeong-Seok; Lee, Hyun-Kyung; Kim, Ki Tae; Jeong, Dae Hoon; Hur, Dae Young

    2014-06-01

    Centrocyte/centroblast marker 1 (CM1) has been identified as a pro-apoptosis molecule on B-cell lymphoma cells as well as several types of cancer cells. In this study, we investigated its signaling mechanism in HeLa cells after treatment with cisplatin in order to potentially identify a new therapeutic target. The CM1 molecule was induced on the surface of cisplatin-exposed HeLa cells. In these cells, ligation of CM1 with anti-CM1 monoclonal antibodies inhibited cell proliferation and produced reactive oxygen species. Fas ligand (FasL) expression was upregulated without upregulating Fas in cisplatin-exposed HeLa cells after CM1 stimulation. Pretreatment with N-acetylcysteine, a pan-capase inhibitor, and ZB4, an antagonistic anti-Fas antibody, effectively inhibited the apoptotic effect triggered by CM1. CM1 ligation induced apoptosis through disruption of the mitochondrial membrane potential, decreased Bcl-2 and phosphorylated ERK expression. These findings identify CM1 as a potential new therapeutic target related to cisplatin-exposed cervical cancer.

  18. Identification and characterization of a broadly cross-reactive HIV-1 human monoclonal antibody that binds to both gp120 and gp41.

    Directory of Open Access Journals (Sweden)

    Mei-Yun Zhang

    Full Text Available Identification of broadly cross-reactive HIV-1-neutralizing antibodies (bnAbs may assist vaccine immunogen design. Here we report a novel human monoclonal antibody (mAb, designated m43, which co-targets the gp120 and gp41 subunits of the HIV-1 envelope glycoprotein (Env. M43 bound to recombinant gp140 s from various primary isolates, to membrane-associated Envs on transfected cells and HIV-1 infected cells, as well as to recombinant gp120 s and gp41 fusion intermediate structures containing N-trimer structure, but did not bind to denatured recombinant gp140 s and the CD4 binding site (CD4bs mutant, gp120 D368R, suggesting that the m43 epitope is conformational and overlaps the CD4bs on gp120 and the N-trimer structure on gp41. M43 neutralized 34% of the HIV-1 primary isolates from different clades and all the SHIVs tested in assays based on infection of peripheral blood mononuclear cells (PBMCs by replication-competent virus, but was less potent in cell line-based pseudovirus assays. In contrast to CD4, m43 did not induce Env conformational changes upon binding leading to exposure of the coreceptor binding site, enhanced binding of mAbs 2F5 and 4E10 specific for the membrane proximal external region (MPER of gp41 Envs, or increased gp120 shedding. The overall modest neutralization activity of m43 is likely due to the limited binding of m43 to functional Envs which could be increased by antibody engineering if needed. M43 may represent a new class of bnAbs targeting conformational epitopes overlapping structures on both gp120 and gp41. Its novel epitope and possibly new mechanism(s of neutralization could helpdesign improved vaccine immunogens and candidate therapeutics.

  19. Cross-reactivity of antibodies with phenolic compounds in pistachios during quantification of ochratoxin A by commercial enzyme-linked immunosorbent assay kits.

    Science.gov (United States)

    Lee, Hyun Jung; Meldrum, Alexander D; Rivera, Nicholas; Ryu, Dojin

    2014-10-01

    Ochratoxin A (OTA), a nephrotoxic mycotoxin, naturally occurs in wide range of agricultural commodities. Typical screening of OTA involves various enzyme-linked immunosorbent assay (ELISA) methods. Pistachio (Pistacia vera L.) is a rich source of phenolic compounds that may result in a false positive due to structural similarities to OTA. The present study investigated the cross-reactivity profiles of phenolic compounds using two commercial ELISA test kits. High-performance liquid chromatography was used to confirm the concentration of OTA in the pistachio samples and compared with the results obtained from ELISA. When the degree of interaction and 50 % inhibitory concentration of phenolic compounds were determined, the cross-reactivity showed a pattern similar to that observed with the commercial ELSIA kits, although quantitatively different. In addition, the degree of interaction increased with the increasing concentration of phenolic compounds. The ELISA value had stronger correlations with the content of total phenolic compound, gallic acid, and catechin (R(2) = 0.757, 0.732, and 0.729, respectively) compared with epicatechin (R(2) = 0.590). These results suggest that phenolic compounds in pistachio skins may cross-react with the OTA antibody and lead to a false positive or to an overestimation of OTA concentration in ELISA-based tests.

  20. Antiviral Polymer Therapeutics

    DEFF Research Database (Denmark)

    Smith, Anton Allen Abbotsford

    2014-01-01

    The field of drug delivery is in essence an exercise in engineered pharmacokinetics. Methods of doing so have been developed through the introduction of a vehicle carrying the drug, either by encapsulation or covalent attachment. The emergence of polymer therapeutics in anticancer therapy has...... the examples of polymer therapeutics being applied as an antiviral treatment are few and far in-between. This work aims to explore antiviral therapeutics, specifically in context of hepatitis virus C (HCV) and HIV. The current treatment of hepatitis C consists of a combination of drugs, of which ribavirin....... Curiously, the therapeutic window of ribavirin was vastly improved in several of these polymers suggesting altered pharmacodynamics. The applicability of liver-targeting sugar moieties is likewise tested in a similarly methodical approach. The same technique of synthesis was applied with zidovudine to make...

  1. The different modes of binding of the dust mite allergens, Der f 7 and Der p 7, on a monoclonal antibody WH9 contribute to the differential reactivity.

    Science.gov (United States)

    Tai, Hsiao-Yun; Zhou, Jia-Kai; Yeh, Chang-Ching; Tam, Ming F; Sheu, Sheh-Yi; Shen, Horng-Der

    2017-06-28

    Der f 7 and Der p 7 are important house dust mite allergens. An IgE-binding inhibition monoclonal antibody WH9 reacts ten folds stronger against Der p 7 than to Der f 7. The purpose of this study is to identify the antigenic determinant(s) and the structural basis of Der f 7 recognize by WH9. WH9-reactive determinant(s) on Der f 7 was identified by immunoblot and immunoblot inhibition. The 3-D binary complex structures of WH9 and the group 7 allergens were simulated with homology modeling and docking methods. WH9 reacted with the Der f 7 f9 fragment. Among the five site-directed Der f 7 mutants, WH9 showed reduced immunoblot reactivity against Der f 7 S156A, D159A and P160A mutants. Only the wild-type protein and the Der f 7 I157A and L158A mutants can inhibit significantly the WH9-binding against Der f 7. The structural model of the Der f 7-WH9 complex suggests residues S156 and D159 of Der f 7 can bind to WH9 via potential hydrogen bonds. The structure models of Der f 7-WH9 and Der p 7-WH9 complexes revealed that the differential modes of binding of Der p 7 and Der f 7 allergens on WH9 contribute to the differential reactivity of WH9 against the Der f 7 and the Der p 7 mite allergens. Copyright © 2017. Published by Elsevier B.V.

  2. Cross-reactivity of human monoclonal antibodies generated with peripheral blood lymphocytes from dengue patients with Japanese encephalitis virus

    Directory of Open Access Journals (Sweden)

    Pipattanaboon C

    2013-08-01

    Full Text Available Chonlatip Pipattanaboon,1,3,8,* Tadahiro Sasaki,2,8,* Mitsuhiro Nishimura,2,8 Chayanee Setthapramote,1,8 Pannamthip Pitaksajjakul,1,4,8 Pornsawan Leaungwutiwong,1,3,8 Kriengsak Limkittikul,5,8 Orapim Puiprom,6 Mikiko Sasayama,6 Panjaporn Chaichana,6 Tamaki Okabayashi,6 Takeshi Kurosu,2,8 Ken-ichiro Ono,7,8 Pongrama Ramasoota,1,4,8 Kazuyoshi Ikuta2,8 1Center of Excellence for Antibody Research, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; 2Department of Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan; 3Department of Microbiology and Immunology, 4Department of Social and Environmental Medicine, 5Department of Tropical Pediatrics, Faculty of Tropical Medicine, Mahidol University, 6Mahidol-Osaka Center for Infectious Diseases, Bangkok, Thailand; 7Medical and Biological Laboratories Corporation Ltd, Nagano, Japan; 8JST/JICA, Science and Technology Research Partnership for Sustainable Development, Tokyo, Japan *These authors made an equal contribution to this study Background: Hybridomas that produce human monoclonal antibodies (HuMAbs against Dengue virus (DV had been prepared previously using peripheral blood lymphocytes from patients with DV during the acute and convalescent phases of a secondary infection. Anti-DV envelope glycoprotein (E 99 clones, anti-DV premembrane protein (prM 8 clones, and anti-DV nonstructural protein 1 (NS1 4 clones were derived from four acute-phase patients, and anti-DV E 2 clones, anti-DV prM 2 clones, and anti-DV NS1 8 clones were derived from five convalescent-phase patients. Methods and results: In the present study, we examined whether these clones cross-reacted with Japanese encephalitis virus (JEV, which belongs to the same virus family. Forty-six of the above-described 99 (46/99 anti-E, 0/8 anti-prM, and 2/4 anti-NS1 HuMAbs from acute-phase, and 0/2 anti-E, 0/2 anti-prM, and 5/8 anti-NS1 HuMAbs from convalescent-phase showed neutralizing activity against

  3. The Diagnostic Utility of Anti-cyclic Citrullinated Peptide Antibodies, Matrix Metalloproteinase-3, Rheumatoid Factor, Erythrocyte Sedimentation Rate, and C-reactive Protein in Patients with Erosive and Non-erosive Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    O. Shovman

    2005-01-01

    Full Text Available Objective: To compare the diagnostic utility of laboratory variables, including matrix metalloproteinase-3 (MMP-3, anti-cyclic citrullinated peptide (CCP antibodies, rheumatoid factor (RF, erythrocyte sedimentation rate (ESR, and C-reactive protein (CRP in patients with erosive and non-erosive rheumatoid arthritis (RA.

  4. Impact of human leukocyte antigen matching and recipients' panel reactive antibodies on two-year outcome in presensitized renal allograft recipients

    Institute of Scientific and Technical Information of China (English)

    MENG Hui-lin; JIN Xun-bo; LI Xiang-tie; WANG Hong-wei; L(U) Jia-ju

    2009-01-01

    Background Renal transplantation in sensitized candidates remains a highly significant challenge worldwide. The production of panel reactive antibody (PRA) against human leukocyte antigen (HLA) is a major risk factor in presensitized recipients. The aim of this study was to evaluate the impact of HLA matching and recipients' PRA on two-year outcome in presensitized renal allograft recipients.Methods We determined the percentage of panel reactivity and specificity of anti-HLA immunoglobulin (Ig) G antibodies in 73 presensitized renal allograft recipients compared with 81 unsensitized recipients (control group). HLA genotyping of both recipients and corresponding donors was performed by PCR with sequence-specific primers (PCR-SSP). We analyzed the factors influencing the early graft outcome (two-year rejection rates and survival rates of the grafts), including HLA mismatching, class and degree of panel reactivity, and target antigen of donors.Results Presensitized recipients had a worse two-year outcome than unsensitized recipients (P=0.019 for rejection rate, P=0.01 for survival rate). The difference in number of HLA-mismatched alleles with either 6-antigen matching (Ag M) standard or amino acid residue matching (Res M) standard was not significant between the rejection and non-rejection groups of presensitized recipients or between the graft survival group and graft loss group. Compared with the control group, recipients with both PRA-Ⅰ and PRA-Ⅱ antibodies had a significantly worse two-year outcome (P=0.001 for rejection rate, P=0.002 for survival rate). The two-year outcomes of the peak PRA ≥50% group and its subgroup, at-transplant PRA ≥50% group, were significantly worse compared with the control group (P=0.025 and P=0.001 for rejection rate, P=0.043 and P=0.024 for survival rate). The rejection rates of the at-transplant target antigen positive group and its subgroup, HLA-Ⅰ target antigen positive group, were significantly higher than the control

  5. Broad-spectrum antiviral agents

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    Jun-Da eZhu

    2015-05-01

    Full Text Available Development of highly effective, broad-spectrum antiviral agents is the major objective shared by the fields of virology and pharmaceutics. Antiviral drug development has focused on targeting viral entry and replication, as well as modulating cellular defense system. High throughput screening of molecules, genetic engineering of peptides, and functional screening of agents have identified promising candidates for development of optimal broad-spectrum antiviral agents to intervene in viral infection and control viral epidemics. This review discusses current knowledge, prospective applications, opportunities, and challenges in the development of broad-spectrum antiviral agents.

  6. Cross-reactive binding of cyclic peptides to an anti-TGFalpha antibody Fab fragment: an X-ray structural and thermodynamic analysis.

    Science.gov (United States)

    Hahn, M; Winkler, D; Welfle, K; Misselwitz, R; Welfle, H; Wessner, H; Zahn, G; Scholz, C; Seifert, M; Harkins, R; Schneider-Mergener, J; Höhne, W

    2001-11-23

    The monoclonal antibody tAb2 binds the N-terminal sequence of transforming growth factor alpha, VVSHFND. With the help of combinatorial peptide libraries it is possible to find homologous peptides that bind tAb2 with an affinity similar to that of the epitope. The conformational flexibility of short peptides can be constrained by cyclization in order to improve their affinity to the antibody and their stability towards proteolysis. Two cyclic peptides which are cross-reactive binders for tAb2 were selected earlier using combinatorial peptide libraries. One is cyclized by an amide bond between the N-alpha group and the side-chain of the last residue (cyclo-SHFNEYE), and the other by a disulfide bridge (cyclo-CSHFNDYC). The complex structures of tAb2 with the linear epitope peptide VVSHFND and with cyclo-SHFNEYE were determined by X-ray diffraction. Both peptides show a similar conformation and binding pattern in the complex. The linear peptide SHFNEYE does not bind tAb2, but cyclo-SHFNEYE is stabilized in a loop conformation suitable for binding. Hence the cyclization counteracts the exchange of aspartate in the epitope sequence to glutamate. Isothermal titration calorimetry was used to characterize the binding energetics of tAb2 with the two cyclic peptides and the epitope peptide. The binding reactions are enthalpically driven with an unfavorable entropic contribution under all measured conditions. The association reactions are characterized by negative DeltaC(p) changes and by the uptake of one proton per binding site. A putative candidate for proton uptake during binding is the histidine residue in each of the peptides. Hydrogen bonds and the putative formation of an electrostatic pair between the protonated histidine and a carboxy group may contribute markedly to the favorable enthalpy of complex formation. Implications to cyclization of peptides for stabilization are discussed.

  7. Anti-citrullinated peptide antibodies in Sudanese patients with Leishmania donovani infection exhibit reactivity not dependent on citrullination.

    Science.gov (United States)

    Åhlin, E; Elshafie, A I; Nur, M A M; Rönnelid, J

    2015-03-01

    African patients with Leishmania donovani infections have signs of strong systemic inflammation and high levels of circulating immune complexes (IC) and rheumatoid factor (RF), all serologic markers of rheumatic disease. As inflammation in general is associated with citrullination, we sought to investigate ACPA responses in Sudanese Leishmania patients. Serum samples were collected from Sudanese patients with visceral leishmaniasis (VL) and post-kala-azar dermal leishmaniasis (PKDL) as well as from ACPA-positive Sudanese rheumatoid arthritis patients and compared to healthy Sudanese controls. Levels of circulating C1q-binding IC and anticyclic citrullinated peptide 2(CCP2) were investigated using ELISA, and RF was measured with nephelometry. C1q adsorption was carried out to investigate anti-CCP2 content in IC. Citrulline specificity was evaluated with control plates with cyclic arginine-containing control peptides. Leishmania-infected patients had elevated levels of RF and circulating IC but also a significant increase in anti-CCP2 (12%) as compared to healthy controls. Anti-CCP2-positive Leishmania patients displayed lower anti-CCP2 levels than Sudanese patients with rheumatoid arthritis (RA), and anti-CCP2 levels in Leishmania patients showed a continuum not resembling the dichotomous pattern seen in patients with RA. Whereas the anti-CCP reactivity of Sudanese RA sera was strictly citrulline dependent, anti-CCP2-positive Leishmania sera reacted equally well with ELISA plates containing arginine control peptides. There was a strong correlation between anti-CCP2 and circulating IC among the Leishmania patients, but IC depletion only marginally diminished anti-CCP2 levels. Our findings stress the importance to interpret a positive CCP test carefully when evaluated in non-rheumatic conditions associated with macrophage activation. © 2015 The Authors. Scandinavian Journal of Immunology published by John Wiley & Sons Ltd on behalf of Scandanavian Society of

  8. La respuesta inmune antiviral

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    Rainel Sánchez de la Rosa

    1998-02-01

    Full Text Available Se expone que los virus son parásitos intracelulares obligados, puesto que no tienen metabolismo propio; esto obliga al sistema inmune a poner en marcha sus mecanismos más especializados para reconocer y eliminar, tanto a los virus libres, como a las células infectadas. Se señala que las células presentadoras de antígenos, los linfocitos B y los T unidos al complejo mayor de histocompatibilidad, forman parte de la organización de la respuesta inmune antiviral; la inducción de esta respuesta con proteínas, péptidos y ADN desnudo, son alternativas actuales tanto en la prevención como en el tratamiento de las infecciones viralesIt is explained that viruses are compulsory intracellular parasites, since they don't have their own metabolism, which makes the immune system to start its mest specialized mechanisms to recognize and eliminate the free viruses and the infected cells. It is stated that the cells presenting antigens, and the B and T lymphocytes together with the major histocompatibility complex, are part of the organization of the immune antiviral response. The induction of this response with proteins, peptides and naked DNA are the present alternatives for the prevention and treatment of viral infections

  9. The IgG antibody reactivity of sera from patients with active chronic hepatitis to a crude liver antigen and liver specific protein (LSP): analysis by ELISA and immunoblotting.

    Science.gov (United States)

    Sundin, U; Heigl, Z; Sundqvist, K G

    1988-11-01

    The antibody reactivity to liver specific protein (LSP) and a crude liver antigen of sera from patients with chronic active hepatitis (CAH) were studied along with other related diseases and healthy individuals. CAH sera containing liver reacting antibodies were selected using an ELISA with a crude liver preparation as antigen and subsequently the specificity was analysed by immunoblotting of SDS-PAGE-separated LSP. The incidence of IgG antibodies to the crude liver antigen and LSP in sera from 15 patients with CAH was 94% and 55% respectively. In the healthy control group (n = 30) the corresponding figures were 3% and 17%. Sera from patients with other autoimmune conditions with considerable reactivity in the crude liver ELISA test were those with antibodies against extractable nuclear antigens (ENA) and thyroid gland antigens, while the anti-nuclear antibody (ANA) group as a whole did not differ from the control group. In immunoblotting of SDS-PAGE-separated crude liver and LSP antigens, the IgG binding pattern of ELISA IgG positive CAH sera and sera from patients with thyroid disease was distinct, with bands corresponding to antigens of molecular weights of 38, 45 and 50 kD which were not observed in ELISA negative CAH sera or in sera from patients with other diseases and among healthy controls.

  10. Comparison of monoclonal antibodies reactive with lymphocyte subsets in routinely fixed paraffin-embedded material: flow cytometric analyses, immunoperoxidase staining and influence of fixatives.

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    Yoshino,Tadashi

    1990-10-01

    Full Text Available We have attempted to clarify the characteristics of monoclonal antibodies (MAbs detecting lymphocyte subsets in fixed materials. We examined by means of flow cytometric technique influences of fixatives and reactivity with malignant lymphomas (MLs. Specific markers for T-cells were UCHL1 and OPD4, which reacted especially with helper/inducer T-cells. MT1 recognized almost all of T-cells from peripheral blood and tonsils, but reacted with a part of B-MLs. As for B-cell markers, L26 was the most reliable marker for B-MLs. L26 and MB1 antigens could not be detected on living cells flow cytometrically. LN1 reacted with a part of T-cells as well as B-cells, but fluorescent intensity of the former was apparently stronger than that of the latter. Although LN2 antigen was located mainly in the cytoplasm close to the nuclear membrane immunohistochemically, it could be detected on living cells flow cytometrically. LN2 positive cells belonged to B-cells in peripheral blood and tonsils. When fixed for relatively short time, B5 and buffered formalin were better for examining MAbs than non-buffered formalin and ethanol.

  11. Panel-reactive antibody levels and renal transplantation rates in sensitized patients after desensitization and human leucocyte antigen amino acid residue matching.

    Science.gov (United States)

    Shang, Wenjun; Dong, Laidong; Feng, Guiwen; Wang, Yue; Pang, Xinlu; Li, Jinfeng; Liu, Lei; Zhang, Weihong

    2013-08-01

    To determine whether a new desensitization protocol (mycophenolate mofetil [MMF], plasmapheresis and antithymocyte globulin [ATG], complemented with human leucocyte antigen [HLA] amino acid residue matching) could reduce panel-reactive antibody (PRA) levels in sensitized patients, to facilitate successful renal transplantation. Patients awaiting transplantation with PRA levels >10% received treatment with MMF; those with PRA levels >30% were also treated with plasmapheresis. Patients whose PRA level was desensitization were eligible for transplantation. When a donor became available, traditional HLA matching and HLA amino acid residue matching were performed. All patients received ATG induction therapy postoperatively. Thirty-two sensitized patients were enrolled. Desensitization produced a significant decrease in PRA levels; 27 patients (84.4%) became eligible for transplantation and 26 (81.2%) subsequently underwent successful transplantation. Residue matching improved the proportion with a mismatch number of 0-1 from 7.7% to 65.4%, compared with traditional HLA matching. Postoperatively, all patients showed immediate graft function. Acute rejection occurred in three patients (11.5%) and infections in seven patients (25.9%); all were treated successfully. The combination of a desensitization protocol (MMF, plasmapheresis and ATG) and residue matching appears to be an effective strategy for sensitized patients awaiting renal transplantation.

  12. Antiviral immunity in amphibians.

    Science.gov (United States)

    Chen, Guangchun; Robert, Jacques

    2011-11-01

    Although a variety of virus species can infect amphibians, diseases caused by ranaviruses ([RVs]; Iridoviridae) have become prominent, and are a major concern for biodiversity, agriculture and international trade. The relatively recent and rapid increase in prevalence of RV infections, the wide range of host species infected by RVs, the variability in host resistance among population of the same species and among different developmental stages, all suggest an important involvement of the amphibian immune system. Nevertheless, the roles of the immune system in the etiology of viral diseases in amphibians are still poorly investigated. We review here the current knowledge of antiviral immunity in amphibians, focusing on model species such as the frog Xenopus and the salamander (Ambystoma tigrinum), and on recent progress in generating tools to better understand how host immune defenses control RV infections, pathogenicity, and transmission.

  13. Induction of cross clade reactive specific antibodies in mice by conjugates of HGP-30 (peptide analog of HIV-1(SF2) p17) and peptide segments of human beta-2-microglobulin or MHC II beta chain.

    Science.gov (United States)

    Zimmerman, D H; Lloyd, J P; Heisey, D; Winship, M D; Siwek, M; Talor, E; Sarin, P S

    2001-09-14

    HGP-30, a 30 amino acid synthetic peptide homologous to a conserved region of HIV-1(SF2) p17 (aa86-115), has previously been shown to elicit both cellular and humoral immune responses when conjugated to KLH and adsorbed to alum. However, the free HGP-30 peptide is not immunogenic in animals. In order to improve the immunogenicity of HGP-30, peptide conjugates consisting of a modified HGP-30 sequence (m-HGP-30/aa82-111) and a peptide segment, residues 38-50, of the MHC I accessory molecule, human beta-2-microglobulin (beta-2-M), referred to as Peptide J, or a peptide from the MHC II beta chain (peptide G) were evaluated in mice. The effects of carriers and adjuvants on serum antibody titers, specificities to various HIV-1 clade peptides similar to HGP-30 and isotype patterns were examined. Peptides J or especially G conjugated to modified-HGP-30 (LEAPS 102 and LEAPS 101, respectively) generated comparable or better immune responses to modified HGP-30 than KLH conjugates as judged by the induction of: (1) similar antibody titers; (2) broader HIV clade antigen binding; and (3) antibody isotype response patterns indicative of a TH1 pathway (i.e. increased amounts of IgG2a and IgG2b antibodies). The ISA 51 and MPL(R)-SE adjuvants induced higher antibody responses than alum, with the ISA 51 being more potent. Immune responses to LEAPS 102, as compared to LEAPS 101, were weaker and slower to develop as determined by antibody titers and cross clade reactivity of the antibodies induced. Compared to KLH conjugates which induced significant anti-KLH antibody titers, minimal antibody responses were observed to peptide G, the more immunogenic conjugate, and peptide J. These results suggest that modified HGP-30 L.E.A.P.S. constructs may be useful as HIV vaccine candidates for preferential induction of TH1 directed cell mediated immune responses.

  14. Species-specific and cross-reactive IgG1 antibody binding to viral capsid protein 1 (VP1 antigens of human rhinovirus species A, B and C.

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    Jua Iwasaki

    Full Text Available BACKGROUND: Human rhinoviruses (HRV are associated with upper and lower respiratory illnesses, including severe infections causing hospitalization in both children and adults. Although the clinical significance of HRV infections is now well established, no detailed investigation of the immune response against HRV has been performed. The purpose of this study was to assess the IgG1 antibody response to the three known HRV species, HRV-A, -B and -C in healthy subjects. METHODS: Recombinant polypeptides of viral capsid protein 1 (VP1 from two genotypes of HRV-A, -B and -C were expressed as glutathione S-transferase (GST fusion proteins and purified by affinity and then size exclusion chromatography. The presence of secondary structures similar to the natural antigens was verified by circular dichroism analysis. Total and species-specific IgG1 measurements were quantitated by immunoassays and immunoabsorption using sera from 63 healthy adults. RESULTS: Most adult sera reacted with the HRV VP1 antigens, at high titres. As expected, strong cross-reactivity between HRV genotypes of the same species was found. A high degree of cross-reactivity between different HRV species was also evident, particularly between HRV-A and HRV-C. Immunoabsorption studies revealed HRV-C specific titres were markedly and significantly lower than the HRV-A and HRV-B specific titres (P<0.0001. A truncated construct of HRV-C VP1 showed greater specificity in detecting anti-HRV-C antibodies. CONCLUSIONS: High titres of IgG1 antibody were bound by the VP1 capsid proteins of HRV-A, -B and -C, but for the majority of people, a large proportion of the antibody to HRV-C was cross-reactive, especially to HRV-A. The improved specificity found for the truncated HRV-C VP1 indicates species-specific and cross-reactive regions could be defined.

  15. Optimizing antiviral agents for hepatitis B management in malignant lymphomas

    Science.gov (United States)

    Ozoya, Oluwatobi O.; Chavez, Julio; Sokol, Lubomir

    2017-01-01

    The global scale of hepatitis B infection is well known but its impact is still being understood. Missed hepatitis B infection impacts lymphoma therapy especially increased risk of hepatitis B virus (HBV) reactivation and poor treatment outcomes. The presence of undiagnosed chronic hepatitis also undermines chronic HBV screening methods that are based on a positive HBsAg alone. The goal of this review is to evaluate the literature for optimizing antiviral therapy for lymphoma patients with HBV infection or at risk of HBV reactivation. Relevant articles for this review were identified by searching PubMed, Embase, Ovid Medline, and Scopus using the following terms, alone and in combination: “chronic hepatitis B”, “occult hepatitis B”, ”special groups”, “malignant lymphoma”, “non-Hodgkin’s lymphoma”, “Hodgkin’s lymphoma”, “immunocompromised host”, “immunosuppressive agents”, “antiviral”, “HBV reactivation”. The period of the search was restricted to a 15-year period to limit the search to optimizing antiviral agents for HBV infection in malignant lymphomas [2001–2016]. Several clinical practice guidelines recommend nucleos(t)ide analogues-entecavir, tenofovir and lamivudine among others. These agents are best initiated along with or prior to immunosuppressive therapy. Additional methods recommended for optimizing antiviral therapy include laboratory modalities such as HBV genotyping, timed measurements of HBsAg and HBV DNA levels to measure and predict antiviral treatment response. In conclusion, optimizing antiviral agents for these patients require consideration of geographic prevalence of HBV, cost of antiviral therapy or testing, screening modality, hepatitis experts, type of immunosuppressive therapy and planned duration of therapy.

  16. Failed detection of Bovine viral diarrhea virus 2 subgenotype a (BVDV-2a) by direct fluorescent antibody test on tissue samples due to reduced reactivity of field isolates to raw anti-BVDV antibody.

    Science.gov (United States)

    Yan, Lifang; Pace, Lanny W; Baughman, Brittany; Wilson, Floyd D; Zhang, Shuping; Zhang, Michael Z

    2016-03-01

    Bovine viral diarrhea virus 1 (BVDV-1) is associated with mild or subclinical infections, whereas BVDV-2 is frequently implicated in outbreaks of severe thrombocytopenia and acute fatal disease. In the present study, the carcass of a beef breed cow and tissue samples of a beef calf were received for laboratory diagnosis. Both animals exhibited severe clinical signs compatible with thrombocytopenia or hemorrhagic syndrome. Direct fluorescent antibody test (DFAT) failed to detect BVDV antigen in the tissue specimens of both cases. However, immunohistochemistry (IHC) revealed the presence of BVDV antigen in oral and esophageal mucosa and Peyer patches of the beef breed cow. Real-time reverse transcription polymerase chain reaction (real-time RT-PCR) detected BVDV-2 in selected tissues of both animals. Subsequently, BVDV was isolated from both cases and subjected to genetic and serologic characterizations. Mutations in the 5'-untranslated genomic region (5'-UTR) primer and probe binding sites and the E2 gene were associated with reduced efficiency of an established real-time RT-PCR assay and amino acid alterations in the E2 glycoprotein, respectively. Both viral isolates were classified by real-time RT-PCR and phylogenetic analysis as BVDV-2 subgenotype a. Unlike BVDV reference strains Singer and 125c, the isolates cross-reacted with anti-BVDV-1 and anti-BVDV-2 reference sera, indicating antigenic variations in field isolates. The isolates also showed reduced reactivity to porcine anti-BVDV antiserum (the raw serum used to produce BVDV DFA conjugate). In summary, data from the present investigation indicated that genetic and antigenic variations affected the performance of detection assays, especially DFAT, highlighting the need for regular evaluation and modification of BVDV tests.

  17. Reactivity of natural and induced human antibodies to MUC1 mucin with MUC1 peptides and n-acetylgalactosamine (GalNAc) peptides.

    Science.gov (United States)

    von Mensdorff-Pouilly, S; Petrakou, E; Kenemans, P; van Uffelen, K; Verstraeten, A A; Snijdewint, F G; van Kamp, G J; Schol, D J; Reis, C A; Price, M R; Livingston, P O; Hilgers, J

    2000-06-01

    Antibodies (Abs) to MUC1 occur naturally in both healthy subjects and cancer patients and can be induced by MUC1 peptide vaccination. We compared the specificity of natural and induced MUC1 Abs with the objective of defining an effective MUC1 vaccine for active immunotherapy of adenocarcinoma patients. Serum samples, selected out of a screened population of 492 subjects for their high levels of IgG and/or IgM MUC1 Abs, were obtained from 55 control subjects and from 26 breast cancer patients before primary treatment, as well as from 19 breast cancer patients immunized with MUC1 peptides coupled to keyhole limpet hemocyanin (KLH) and mixed with QS-21. The samples were tested with enzyme-linked immunoassays for reactivity with (1) overlapping hepta- and 20-mer peptides spanning the MUC1 tandem repeat sequence; (2) two modified 60-mer peptides with substitutions in the PDTR (PDTA) or in the STAPPA (STAAAA) sequence of each tandem repeat; and (3) four 60-mer glycopeptides with each 1, 2, 3 and 5 mol N-acetylgalactosamine (GalNAc) per repeat. More than one minimal epitopic sequence could be defined, indicating that Abs directed to more than one region of the MUC1 peptide core can coexist in one and the same subject. The most frequent minimal epitopic sequence of natural MUC1 IgG and IgM Abs was RPAPGS, followed by PPAHGVT and PDTRP. MUC1 peptide vaccination induced high titers of IgM and IgG Abs predominantly directed, respectively, to the PDTRPAP and the STAPPAHGV sequences of the tandem repeat. Natural MUC1 Abs from breast cancer patients reacted more strongly with the N-acetylgalactosamine (GalNAc) peptides than with the naked 60-mer peptide, while reactivity with the GalNAc-peptides was significantly reduced (2-tailed p < 0.0001) in the MUC1 IgG and IgM Abs induced by MUC1 peptide vaccination. Whereas in cancer patients glycans appear to participate in epitope conformation, the epitope(s) recognized by MUC1 Abs induced by peptide vaccination are already masked by

  18. Antiviral Biologic Produced in DNA Vaccine/Goose Platform Protects Hamsters Against Hantavirus Pulmonary Syndrome When Administered Post-exposure

    Science.gov (United States)

    Henderson, Thomas; Nilles, Matthew L.; Kwilas, Steve A.; Josleyn, Matthew D.; Hammerbeck, Christopher D.; Schiltz, James; Royals, Michael; Ballantyne, John; Hooper, Jay W.; Bradley, David S.

    2015-01-01

    Andes virus (ANDV) and ANDV-like viruses are responsible for most hantavirus pulmonary syndrome (HPS) cases in South America. Recent studies in Chile indicate that passive transfer of convalescent human plasma shows promise as a possible treatment for HPS. Unfortunately, availability of convalescent plasma from survivors of this lethal disease is very limited. We are interested in exploring the concept of using DNA vaccine technology to produce antiviral biologics, including polyclonal neutralizing antibodies for use in humans. Geese produce IgY and an alternatively spliced form, IgYΔFc, that can be purified at high concentrations from egg yolks. IgY lacks the properties of mammalian Fc that make antibodies produced in horses, sheep, and rabbits reactogenic in humans. Geese were vaccinated with an ANDV DNA vaccine encoding the virus envelope glycoproteins. All geese developed high-titer neutralizing antibodies after the second vaccination, and maintained high-levels of neutralizing antibodies as measured by a pseudovirion neutralization assay (PsVNA) for over 1 year. A booster vaccination resulted in extraordinarily high levels of neutralizing antibodies (i.e., PsVNA80 titers >100,000). Analysis of IgY and IgYΔFc by epitope mapping show these antibodies to be highly reactive to specific amino acid sequences of ANDV envelope glycoproteins. We examined the protective efficacy of the goose-derived antibody in the hamster model of lethal HPS. α-ANDV immune sera, or IgY/IgYΔFc purified from eggs, were passively transferred to hamsters subcutaneously starting 5 days after an IM challenge with ANDV (25 LD50). Both immune sera, and egg-derived purified IgY/IgYΔFc, protected 8 of 8 and 7 of 8 hamsters, respectively. In contrast, all hamsters receiving IgY/IgYΔFc purified from normal geese (n=8), or no-treatment (n=8), developed lethal HPS. These findings demonstrate that the DNA vaccine/goose platform can be used to produce a candidate antiviral biological product

  19. Antiviral Biologic Produced in DNA Vaccine/Goose Platform Protects Hamsters Against Hantavirus Pulmonary Syndrome When Administered Post-exposure.

    Directory of Open Access Journals (Sweden)

    Nicole Haese

    Full Text Available Andes virus (ANDV and ANDV-like viruses are responsible for most hantavirus pulmonary syndrome (HPS cases in South America. Recent studies in Chile indicate that passive transfer of convalescent human plasma shows promise as a possible treatment for HPS. Unfortunately, availability of convalescent plasma from survivors of this lethal disease is very limited. We are interested in exploring the concept of using DNA vaccine technology to produce antiviral biologics, including polyclonal neutralizing antibodies for use in humans. Geese produce IgY and an alternatively spliced form, IgYΔFc, that can be purified at high concentrations from egg yolks. IgY lacks the properties of mammalian Fc that make antibodies produced in horses, sheep, and rabbits reactogenic in humans. Geese were vaccinated with an ANDV DNA vaccine encoding the virus envelope glycoproteins. All geese developed high-titer neutralizing antibodies after the second vaccination, and maintained high-levels of neutralizing antibodies as measured by a pseudovirion neutralization assay (PsVNA for over 1 year. A booster vaccination resulted in extraordinarily high levels of neutralizing antibodies (i.e., PsVNA80 titers >100,000. Analysis of IgY and IgYΔFc by epitope mapping show these antibodies to be highly reactive to specific amino acid sequences of ANDV envelope glycoproteins. We examined the protective efficacy of the goose-derived antibody in the hamster model of lethal HPS. α-ANDV immune sera, or IgY/IgYΔFc purified from eggs, were passively transferred to hamsters subcutaneously starting 5 days after an IM challenge with ANDV (25 LD50. Both immune sera, and egg-derived purified IgY/IgYΔFc, protected 8 of 8 and 7 of 8 hamsters, respectively. In contrast, all hamsters receiving IgY/IgYΔFc purified from normal geese (n=8, or no-treatment (n=8, developed lethal HPS. These findings demonstrate that the DNA vaccine/goose platform can be used to produce a candidate antiviral

  20. C-reactive protein and anti-Chlamydia pneumoniae antibodies as risk factors of cardiovascular death in incident patients on peritoneal dialysis.

    Science.gov (United States)

    Paniagua, Ramón; Frías, Yolanda; de Ventura, Maria Jesús; Rodríguez, Ernesto; Hurtado, María Elena; Alcántara, Guadalupe; Vázquez, Roberto; Ortiz, Ruth; Salcedo, Mario; Rios, Maria Elena; Kaji, Julio; Amato, Dante

    2003-01-01

    Recently it has been pointed out that inflammation and infections caused by germs such as Chlamydia pneumoniae are independent cardiovascular risk factors for the general population, but information about these relationships in dialysis patients is scarce. This work was done to analyze the association of C-reactive protein (CRP) and IgG anti-Chlamydia pneumoniae antibodies (anti-Chlp-IgG) as independent cardiovascular risk factors in incident patients on continuous ambulatory peritoneal dialysis (CAPD). Single-cohort, prospective observational study. Three CAPD centers from the Instituto Mexicano del Seguro Social, and one from the Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado, Mexico. A cohort of 75 adult incident patients on CAPD, without clinical signs of congestive heart failure, coronary heart disease, or peripheral arterial insufficiency. No restrictions for age, gender, or cause of renal failure were applied. Mortality. Demographic variables, body composition by electrical bioimpedance, serum glucose, urea, creatinine, lipids, homocysteine, nutritional markers (albumin, prealbumin, and transferrin), CRP, and anti-Chlp-IgG were measured and registered at the time of the first admission. When a patient died, the cause of death was determined by review of the clinical chart. Mean follow-up time was 10.25 patient-months. There were 14 cardiovascular deaths. CRP was positive (> 10 mg/L) in 64% of the patients, and anti-Chlp-IgG in 64%; 29% of the patients were positive for both markers. The relative risk for cardiovascular mortality was 6.23 for patients positive for either CRP or anti-Chlp-IgG, and increased to 9.52 when both markers were positive. Multivariate analysis revealed that CRP and anti-Chlp-IgG were stronger cardiovascular death predictors than age, diabetes, and nutritional status. These data suggest that inflammation and the presence of Chlamydia pneumoniae infections are important predictors of cardiovascular death in

  1. The diagnostic utility of anti-cyclic citrullinated peptide antibodies, matrix metalloproteinase-3, rheumatoid factor, erythrocyte sedimentation rate, and C-reactive protein in patients with erosive and non-erosive rheumatoid arthritis.

    Science.gov (United States)

    Shovman, O; Gilburd, B; Zandman-Goddard, G; Sherer, Y; Orbach, H; Gerli, R; Shoenfeld, Y

    2005-09-01

    To compare the diagnostic utility of laboratory variables, including matrix metalloproteinase-3 (MMP-3), anticyclic citrullinated peptide (CCP) antibodies, rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) in patients with erosive and non-erosive rheumatoid arthritis (RA). We assembled a training set, consisting of 60 patients with RA, all fulfilling the revised criteria of the American College of Rheumatology. A commercial enzyme linked immunosorbent assay (ELISA) was used both to test for anti-CCP antibodies (second generation ELISA kit) and MMP; RF were detected by latex-enhanced immunonephelometric assay. CRP was measured by latex turbidimetric immunoassay. The levels of anti-CCP antibody titers and ESR were significantly higher in patients with erosive disease than those in non-erosive RA patients (p elevated titers of anti-CCP antibodies was found in RA patients with erosions compared to patients with non-erosive RA (78.3% vs. 43.2% respectively). The ROC curves of anti-CCP passed closer to the upper left corner than those other markers and area under the curve (AUC) of anti-CCP was significantly larger than AUC of other markers (0.755 for anti-CCP, 0.660 for ESR, 0.611 for CRP, 0.577 for RF, and 0.484 for MMP-3 female). A positive predictive value was higher for anti-CCP antibodies in comparison to other markers. We did not find significant statistical correlation between anti-CCP antibody titers and inflammatory markers such as ESR or CRP. However, we confirmed the correlation of elevated titers of anti-CCP antibodies and RF in both groups of patients whereas the degree of correlation was more significant in non-erosive patients. The results of our study suggest that the presence of elevated anti-CCP antibody titers have better diagnostic performance than MMP-3, RF, CRP and ESR in patients with erosive RA.

  2. Current trend of induction and maintenance treatment in positive panel-reactive antibody patients: a report on OPTN/UNOS kidney transplant registry data

    Institute of Scientific and Technical Information of China (English)

    Junchao Cai; Paul I. Terasaki

    2011-01-01

    Background The status of sensitization in kidney transplant recipients in the last 10 years and the trend of induction and maintenance therapy in patients of different panel-reactive antibody (PRA) levels have not been analyzed. The aim of this study was to investigate the current status of pre-transplant sensitization and its association with graft outcome.Methods A total of 155 570 kidney transplants reported to United Network for Organ Sharing (UNOS) during 2000-2009 were included in this study. We investigated the current status of pre-transplant sensitization and its association with graft outcome, and also compared the usage trend of 16 induction agents and 7 maintenance immunosuppressants in patients at different PRA levels. The difference of distributions of categorical variables between groups was investigated using the chi-square test. Unpaired t test or one-way analysis of variance (ANOVA) were used for numerical variables. The survival rates of transplant recipients were estimated using Kaplan-Meier methods and significance was determined by Log-rank test. Two-side P value <0.05 was considered statistically significant. All statistical analyses were performed using STATA 10 with all available updates as of March 2010 (StataCorp LP, College Station, Texas 77845, USA).Results Despite the fact of the decreased percentages of kidney transplant recipients with presensitization history, the mean PRA levels of all kidney recipients has been increasing in the last 7 years, which was possibly due to the introduction of more sensitive antibody testing techniques. The percentage of patients with treated rejection episodes within one year post-transplant were significantly higher in sensitized patients (PRA=50%-100%:14.3% and PRA=1%-49%:13.9%) than in non-sensitized patients (12.4%). Both 1- and 5-year graft survival rates improved in the last 10 years; this was more significant in high PRA patients. Thymoglobulin was the most commonly used induction agent in

  3. High titers of anti-HBs prevent rituximab-related viral reactivation in resolved hepatitis B patient with non-Hodgkin's lymphoma.

    Science.gov (United States)

    Cho, Yuri; Yu, Su Jong; Cho, Eun Ju; Lee, Jeong-Hoon; Kim, Tae Min; Heo, Dae Seog; Kim, Yoon Jun; Yoon, Jung-Hwan

    2016-06-01

    Rituximab, an anti-CD20 monoclonal antibody, is associated with an increased risk of hepatitis B virus (HBV) reactivation. This study aimed to determine the predictive factors for rituximab-related HBV reactivation in resolved hepatitis B patients, defined as HBsAg-negative, anti-HBc-positive, and undetectable HBV DNA. Among 840 consecutive patients with CD20-positive B-cell lymphoma who received rituximab-based chemotherapy from 2003 through 2014 at Seoul National University Hospital, 732 patients were excluded because either anti-HBc was not assessed or they were HBsAg-seropositive. This retrospective study included 108 resolved hepatitis B patients. During a median 33.5-month follow-up period, eight cases of HBV reactivation occurred only among the patients with low anti-HBs titers (anti-HBs titers were the protective factors for HBV reactivation (hazard ratio [HR], 0.90 and 0.95, respectively). Among those who did not receive antiviral prophylaxis, patients with high baseline anti-HBs (≥100 mIU/ml) experienced significantly lower risk of HBV reactivation (HR, 0.49; P = 0.006) than the patients with low baseline anti-HBs (anti-HBs titer at baseline and antiviral prophylaxis prevented HBV reactivation, suggesting antiviral prophylaxis should be considered according to baseline anti-HBs titer. Meticulous follow-up for ALT and HBV DNA without antiviral prophylaxis might be possible for the patients with high baseline anti-HBs (≥100 mIU/ml).

  4. Antiviral Drug Research Proposal Activity

    Directory of Open Access Journals (Sweden)

    Lisa Injaian

    2011-03-01

    Full Text Available The development of antiviral drugs provides an excellent example of how basic and clinical research must be used together in order to achieve the final goal of treating disease. A Research Oriented Learning Activity was designed to help students to better understand how basic and clinical research can be combined toward a common goal. Through this project students gained a better understanding of the process of scientific research and increased their information literacy in the field of virology. The students worked as teams to research the many aspects involved in the antiviral drug design process, with each student becoming an "expert" in one aspect of the project. The Antiviral Drug Research Proposal (ADRP culminated with students presenting their proposals to their peers and local virologists in a poster session. Assessment data showed increased student awareness and knowledge of the research process and the steps involved in the development of antiviral drugs as a result of this activity.

  5. Emerging antiviral drugs.

    Science.gov (United States)

    De Clercq, Erik

    2008-09-01

    Foremost among the newly described antiviral agents that may be developed into drugs are, for the treatment of human papilloma virus (HPV) infections, cPrPMEDAP; for the treatment of herpes simplex virus (HSV) infections, BAY 57-1293; for the treatment of varicella-zoster virus (VZV) infections, FV-100 (prodrug of Cf 1743); for the treatment of cytomegalovirus (CMV) infections, maribavir; for the treatment of poxvirus infections, ST-246; for the treatment of hepatitis B virus (HBV) infections, tenofovir disoproxil fumarate (TDF) (which in the meantime has already been approved in the EU); for the treatment of various DNA virus infections, the hexadecyloxypropyl (HDP) and octadecyloxyethyl (ODE) prodrugs of cidofovir; for the treatment of orthomyxovirus infections (i.e., influenza), peramivir; for the treatment of hepacivirus infections (i.e., hepatitis C), the protease inhibitors telaprevir and boceprevir, the nucleoside RNA replicase inhibitors (NRRIs) PSI-6130 and R1479, and various non-nucleoside RNA replicase inhibitors (NNRRIs); for the treatment of human immunodeficiency virus (HIV) infections, integrase inhibitors (INIs) such as elvitegravir, nucleoside reverse transcriptase inhibitors (NRTIs) such as apricitabine, non-nucleoside reverse transcriptase inhibitors (NNRTIs) such as rilpivirine and dapivirine; and for the treatment of both HCV and HIV infections, cyclosporin A derivatives such as the non-immunosuppressive Debio-025.

  6. Relative reactivity of HIV-1 polyclonal plasma antibodies directed to V3 and MPER regions suggests immunodominance of V3 over MPER and dependence of high anti-V3 antibody titers on virus persistence.

    Science.gov (United States)

    Andrabi, Raiees; Choudhary, Alok K; Bala, Manju; Kalra, Rajesh; Prakash, S S; Pandey, R M; Luthra, Kalpana

    2011-10-01

    Antibodies to two crucial regions, the third variable loop (V3) of gp120 and the membrane-proximal external region (MPER) of gp41 are important for HIV-1 neutralization. We here evaluated the relative binding of polyclonal plasma antibodies from 99 HIV-1-infected individuals from India to the consensus-C V3 and MPER peptides and observed immunodominance of V3 over MPER (p antibody correlates with clinical parameters. Our results revealed that anti-V3 antibody titers are significantly lower in patients on ART compared to drug-naive individuals (p antibodies are dependent on persistence of virus in circulation, while antibodies to MPER are probably not.

  7. the Study of Hepatitis B Virus Reactivation

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    Hepatitis B virus (HBV) reactivation after chemotherapy or immunosuppressive therapy is a cause of liver-related morbidity and mortality. Not all chronic hepatitis B patients will lead to HBV reactivation. The incidence is 0.3%-30.2%according to the reports. The mechanism of HBV reactivation is still unclear, but it is believed that the viral load is increasing due to the suppression of immune response. No uniform diagnostic criteria are available. HBV reactivation can be confirmed by an increase of serum HBV DNA level. Recently, awareness of reactivation of occult HBV has been improved, especially in HBV endemic area. Preemptive antiviral therapy was the best approach to prevent the HBV reactivation. HBV reactivation can lead to acute hepatitis, severe hepatitis and acute liver failure. Therefore, it is worthy of great attention and further study. Antiviral therapy is safe and effective to prevent HBV reactivation.

  8. Analysis of Platelet-Reactive Antibodies in Patients Who Were Refractory to Platelet Transfusions in Foshan Area%佛山地区血小板输注无效患者的血小板抗体分析

    Institute of Scientific and Technical Information of China (English)

    伍伟健; 王文敬; 卢瑾; 周健欣; 朱业华

    2014-01-01

    目的 探讨佛山地区血小板输注无效(PTR)患者血小板(PLT)抗体特异性、抗体阳性率及其相关因素,为制定PLT输注策略提供参考依据.方法 选择2012年1月至2013年8月,佛山地区5所医院收治的55例PTR患者作为研究对象(本研究遵循的程序符合各病例收集医院人体试验委员会制定的伦理学标准,得到该委员会批准,并征得受试对象的知情同意,并与之签订临床研究知情同意书).采用固相凝集法检测PTR患者血清中的PLT抗体.计算PLT同种抗体检出率和人类白细胞抗原(HLA)、人类血小板抗原(HPA)抗体阳性率,并分析年龄和输血次数对PLT抗体阳性率的影响.结果 PTR患者PLT同种抗体检出率为58.2% (32/55),其中同种HPA抗体阳性率为21.8% (12/55),同种HLA抗体阳性率为50.9%(28/55),抗-HLA占所有免疫性抗体的87.5% (28/32);在检出HPA抗体的患者中有66.7%(8/12)的患者同时检出HLA抗体.PLT自身抗体阳性率为7.3%(4/55).女性患者中PLT抗体阳性率为60.61%(20/33),略高于男性的54.5%(12/22),但两者比较差异无统计学意义(x2=0.01,P>0.05).PLT抗体阳性率随输血次数增加而呈增高趋势(x2趋势=13.14,P<0.05),以输血次数为4~6次时增幅最大.结论 佛山地区PTR患者中PLT同种抗体以HLA抗体多见,其次为HPA抗体,少数患者还存在PLT自身抗体;PLT同种抗体阳性率随输血次数增加呈增高趋势,而与患者性别无关.%Objective To detect and determine the correlation factors,specificity and positive rate of platelet (PLT)-reactive antibodies in patients who were refractory to platelet transfusions (RPT) in Foshan area,and to provide a reference basis for formulating marketing strategy of PLT transfusions.Methods From January 2012 to August 2013,55 RPT patients who were inspected by five different hospitals in Foshan area were included in this study.The study protocol was approved by the Ethical Review Board of

  9. Cross-reactive neuraminidase antibodies afford partial protection against H5N1 in mice and are present in unexposed humans.

    Directory of Open Access Journals (Sweden)

    Matthew R Sandbulte

    2007-02-01

    Full Text Available BACKGROUND: A pandemic H5N1 influenza outbreak would be facilitated by an absence of immunity to the avian-derived virus in the human population. Although this condition is likely in regard to hemagglutinin-mediated immunity, the neuraminidase (NA of H5N1 viruses (avN1 and of endemic human H1N1 viruses (huN1 are classified in the same serotype. We hypothesized that an immune response to huN1 could mediate cross-protection against H5N1 influenza virus infection. METHODS AND FINDINGS: Mice were immunized against the NA of a contemporary human H1N1 strain by DNA vaccination. They were challenged with recombinant A/Puerto Rico/8/34 (PR8 viruses bearing huN1 (PR8-huN1 or avN1 (PR8-avN1 or with H5N1 virus A/Vietnam/1203/04. Additional naïve mice were injected with sera from vaccinated mice prior to H5N1 challenge. Also, serum specimens from humans were analyzed for reactivity with avN1. Immunization elicited a serum IgG response to huN1 and robust protection against the homologous challenge virus. Immunized mice were partially protected from lethal challenge with H5N1 virus or recombinant PR8-avN1. Sera transferred from immunized mice to naïve animals conferred similar protection against H5N1 mortality. Analysis of human sera showed that antibodies able to inhibit the sialidase activity of avN1 exist in some individuals. CONCLUSIONS: These data reveal that humoral immunity elicited by huN1 can partially protect against H5N1 infection in a mammalian host. Our results suggest that a portion of the human population could have some degree of resistance to H5N1 influenza, with the possibility that this could be induced or enhanced through immunization with seasonal influenza vaccines.

  10. Fatty acid acylated antibodies against virus suppress its reproduction in cells.

    Science.gov (United States)

    Kabanov, A V; Ovcharenko, A V; Melik-Hubarov, N S; Bannikov, A I; Alakhov VYu; Kiselev, V I; Sveshnikov, P G; Kiselev, O I; Levashov, A V; Severin, E S

    1989-07-03

    A method for suppression of virus reproduction in cells using fatty acylated antiviral antibodies, which in contrast to non-modified antibodies are capable of intracellular penetration, has been suggested. The addition of stearoylated antiviral antibodies to influenza A/Chili virus-infected cells causes a 100-fold suppression of virus reproduction. Non-modified antibodies do not produce any effect on virus reproduction.

  11. Aleutian disease of mink: the antibody response of sapphire and pastel mink to Aleutian disease virus.

    Science.gov (United States)

    Bloom, M E; Race, R E; Hadlow, W J; Chesebro, B

    1975-10-01

    The specific antiviral antibody response of sapphire and pastel mink to Pullman strain of ADV has been examined. Sapphire mink inoculated with from 300,000-3 LD50 developed high levels of specific antibody and AD. Pastel mink inoculated with parallel doses of ADV also produced antibody but did not develop AD. The low incidence of AD in pastel mink inoculated with Pullman strain of ADV is probably related to factors other than antiviral antibody.

  12. Human Papillomavirus neutralizing and cross-reactive antibodies induced in HIV-positive subjects after vaccination with quadrivalent and bivalent HPV vaccines

    DEFF Research Database (Denmark)

    Faust, Helena; Nielsen, Lars Toft; Sehr, Peter;

    2016-01-01

    Ninety-one HIV-infected individuals (61 men and 30 women) were randomized to vaccination either with quadrivalent (Gardasil™) or bivalent (Cervarix™) HPV vaccine. Neutralizing and specific HPV-binding serum antibodies were measured at baseline and 12 months after the first vaccine dose. Presence...... of neutralizing and binding antibodies had good agreement (average Kappa for HPV types 6, 11, 16, 18, 31, 33 and 45 was 0.65). At baseline, 88% of subjects had antibodies against at least one genital HPV. Following vaccination with Cervarix™, all subjects became seropositive for HPV16 and 18. After Gardasil......™ vaccination, 96% of subjects seroconverted for HPV16 and 73% for HPV18. Levels of HPV16-specific antibodies were 10IU in 85% of study subjects after vaccination. Antibodies against non-vaccine HPV types appeared after Gardasil...

  13. Serum Dried Samples to Detect Dengue Antibodies: A Field Study

    Directory of Open Access Journals (Sweden)

    Angelica Maldonado-Rodríguez

    2017-01-01

    Full Text Available Background. Dried blood and serum samples are useful resources for detecting antiviral antibodies. The conditions for elution of the sample need to be optimized for each disease. Dengue is a widespread disease in Mexico which requires continuous surveillance. In this study, we standardized and validated a protocol for the specific detection of dengue antibodies from dried serum spots (DSSs. Methods. Paired serum and DSS samples from 66 suspected cases of dengue were collected in a clinic in Veracruz, Mexico. Samples were sent to our laboratory, where the conditions for optimal elution of DSSs were established. The presence of anti-dengue antibodies was determined in the paired samples. Results. DSS elution conditions were standardized as follows: 1 h at 4°C in 200 µl of DNase-, RNase-, and protease-free PBS (1x. The optimal volume of DSS eluate to be used in the IgG assay was 40 µl. Sensitivity of 94%, specificity of 93.3%, and kappa concordance of 0.87 were obtained when comparing the antidengue reactivity between DSSs and serum samples. Conclusion. DSS samples are useful for detecting anti-dengue IgG antibodies in the field.

  14. Viral Ancestors of Antiviral Systems

    Directory of Open Access Journals (Sweden)

    Luis P. Villarreal

    2011-10-01

    Full Text Available All life must survive their corresponding viruses. Thus antiviral systems are essential in all living organisms. Remnants of virus derived information are also found in all life forms but have historically been considered mostly as junk DNA. However, such virus derived information can strongly affect host susceptibility to viruses. In this review, I evaluate the role viruses have had in the origin and evolution of host antiviral systems. From Archaea through bacteria and from simple to complex eukaryotes I trace the viral components that became essential elements of antiviral immunity. I conclude with a reexamination of the ‘Big Bang’ theory for the emergence of the adaptive immune system in vertebrates by horizontal transfer and note how viruses could have and did provide crucial and coordinated features.

  15. Viral ancestors of antiviral systems.

    Science.gov (United States)

    Villarreal, Luis P

    2011-10-01

    All life must survive their corresponding viruses. Thus antiviral systems are essential in all living organisms. Remnants of virus derived information are also found in all life forms but have historically been considered mostly as junk DNA. However, such virus derived information can strongly affect host susceptibility to viruses. In this review, I evaluate the role viruses have had in the origin and evolution of host antiviral systems. From Archaea through bacteria and from simple to complex eukaryotes I trace the viral components that became essential elements of antiviral immunity. I conclude with a reexamination of the 'Big Bang' theory for the emergence of the adaptive immune system in vertebrates by horizontal transfer and note how viruses could have and did provide crucial and coordinated features.

  16. Viral Ancestors of Antiviral Systems

    Science.gov (United States)

    Villarreal, Luis P.

    2011-01-01

    All life must survive their corresponding viruses. Thus antiviral systems are essential in all living organisms. Remnants of virus derived information are also found in all life forms but have historically been considered mostly as junk DNA. However, such virus derived information can strongly affect host susceptibility to viruses. In this review, I evaluate the role viruses have had in the origin and evolution of host antiviral systems. From Archaea through bacteria and from simple to complex eukaryotes I trace the viral components that became essential elements of antiviral immunity. I conclude with a reexamination of the ‘Big Bang’ theory for the emergence of the adaptive immune system in vertebrates by horizontal transfer and note how viruses could have and did provide crucial and coordinated features. PMID:22069523

  17. Development of a monoclonal antibody-based broad-specificity ELISA for fluroquinolone antibiotics in foods and molecular modeling studies of cross-reactive compounds

    Science.gov (United States)

    Development of a competitive indirect enzyme-linked immunosorbent assay (ciELISA) with monoclonal antibodies (Mabs) having broad specificity for fluoroquinolone (FQ) antibiotics is described. Four FQs, ciprofloxacin (CIP), norfloxacin (NOR), enrofloxacin (ENR) and ofloxacin (OFL) were conjugated to...

  18. The NTS-DBL2X region of VAR2CSA Induces cross-reactive antibodies that inhibit adhesion of several Plasmodium falciparum isolates to chondroitin sulfate A

    DEFF Research Database (Denmark)

    Bigey, Pascal; Gnidehou, Sédami; Doritchamou, Justin

    2011-01-01

    is difficult. Methods. Using genetic immunization, we raised polyclonal antisera against overlapping segments of VAR2CSA in mice and rabbits. The adhesion-inhibition capacities of induced antisera and of specific antibodies purified from plasma of malaria-exposed pregnant women were assessed on laboratory....... The latter has been clearly associated to increased morbidity and mortality of the infants. Acquired anti-VAR2CSA antibodies have been associated with improved pregnancy outcomes, suggesting a vaccine could prevent the syndrome. However, identifying functionally important regions in the large VAR2CSA protein......-adapted parasite lines and field isolates expressing VAR2CSA. Competition enzyme-linked immunosorbent assay (ELISA) was employed to analyze functional resemblance between antibodies induced in animals and those naturally acquired by immune multigravidae. Results. Antibodies targeting the N-terminal sequence (NTS...

  19. Serodiagnosis of Zika virus (ZIKV) infections by a novel NS1-based ELISA devoid of cross-reactivity with dengue virus antibodies: a multicohort study of assay performance, 2015 to 2016

    Science.gov (United States)

    Steinhagen, Katja; Probst, Christian; Radzimski, Christiane; Schmidt-Chanasit, Jonas; Emmerich, Petra; van Esbroeck, Marjan; Schinkel, Janke; Grobusch, Martin P; Goorhuis, Abraham; Warnecke, Jens M; Lattwein, Erik; Komorowski, Lars; Deerberg, Andrea; Saschenbrecker, Sandra; Stöcker, Winfried; Schlumberger, Wolfgang

    2016-01-01

    Serological diagnosis of Zika virus (ZIKV) infections is challenging due to high cross-reactivity between flaviviruses. We evaluated the diagnostic performance of a novel anti-ZIKV ELISA based on recombinant ZIKV non-structural protein 1 (NS1). Assay sensitivity was examined using sera from 27 patients with reverse transcription (RT)-PCR-confirmed and 85 with suspected ZIKV infection. Specificity was analysed using sera from 1,015 healthy individuals. Samples from 252 patients with dengue virus (n = 93), West Nile virus (n = 34), Japanese encephalitis virus (n = 25), chikungunya virus (n = 19) or Plasmodium spp. (n = 69) infections and from 12 yellow fever-vaccinated individuals were also examined. In confirmed ZIKV specimens collected ≥ 6 days after symptom onset, ELISA sensitivity was 58.8% (95% confidence interval (CI): 36.0–78.4) for IgM, 88.2% (95% CI: 64.4–98.0) for IgG, and 100% (95% CI: 78.4–100) for IgM/IgG, at 99.8% (95% CI: 99.2–100) specificity. Cross-reactivity with high-level dengue virus antibodies was not detected. Among patients with potentially cross-reactive antibodies anti-ZIKV positive rates were 0.8% (95% CI: 0–3.0) and 0.4% (95% CI: 0–2.4) for IgM and IgG, respectively. Providing high specificity and low cross-reactivity, the NS1-based ELISA has the potential to aid in counselling patients, pregnant women and travellers after returning from ZIKV-endemic areas. PMID:28006649

  20. The role of β2-glycoprotein I (β2GPI) carbohydrate chains in the reactivity of anti-β2GPI antibodies from patients with primary antiphospholipid syndrome and in the activation and differentiation of U937 cells.

    Science.gov (United States)

    Hernández-Ramírez, Diego F; Olivares-Martínez, Elizabeth; Núñez-Álvarez, Carlos A; Chavelas, Eneas A; García-Hernández, Enrique; Gómez-Hernández, Gregoria; Llorente, Luis; Cabral, Antonio R

    2014-10-10

    Several studies have shown that conformational changes of β(2)-glycoprotein I (β(2)GPI) when bound to negatively charged components expose cryptic epitopes and subsequent binding of anti-β(2)GPI from patients with antiphospholipid syndrome (APS). However, the role of the carbohydrate chains of β(2)GPI in this anti-β(2)GPI reactivity is poorly understood. We therefore studied the reactivity and inhibition of anti-β(2)GPI antibodies from APS patients with native, partially glycosylated β(2)GPI (pdβ(2)GPI; without sialic acid) and completely deglycosylated β(2)GPI (cdβ(2)GPI). To determine the potential biologic importance of these glycoforms and their interaction with anti-β(2)GPI in vitro, stimulation assays were performed with the U937 cell line. Circular dichroism (CD) and fluorescence analysis of the three β(2)GPI forms were also studied. We found an increased reactivity of anti-β(2)GPI against pdβ(2)GPI and cdβ(2)GPI compared to native β(2)GPI. Both deglycosylated β(2)GPI isoforms showed higher inhibition of the anti-β(2)GPI reactivity than the native protein in soluble-phase. Likewise, the antibody/β(2)GPI/glycoform complexes increased the synthesis of IL-6, IFNγ and TNFα and the expression of HLA-DR, CD14 and CD11c in U937 cells. CD and fluorescence studies of the glycoforms yielded considerable changes in the fluorescence signals. Our work suggests that the partial or complete removal of the carbohydrate chains uncover cryptic epitopes present in β(2)GPI. The differentiation and increased synthesis of pro-inflammatory cytokines by U937 cells in vitro may have pathogenetic implications.

  1. Hepatitis C virus: Virology, diagnosis and management of antiviral therapy

    Institute of Scientific and Technical Information of China (English)

    Stéphane Chevaliez; Jean-Michel Pawlotsky

    2007-01-01

    Hepatitis C virus (HCV) infects approximately 170 million individuals worldwide. Prevention of HCV infection complications is based on antiviral therapy with the combination of pegylatecl interferon alfa and ribavirin.The use of serological and virological tests has become essential in the management of HCV infection in order to diagnose infection, guide treatment decisions and assess the virological response to antiviral therapy. Anti-HCV antibody testing and HCV RNA testing are used to diagnose acute and chronic hepatitis C. The HCV genotype should be systematically determined before treatment, as it determines the indication, the duration of treatment,the dose of ribavirin and the virological monitoring procedure. HCV RNA monitoring during therapy is used to tailor treatment duration in HCV genotype 1 infection, and molecular assays are used to assess the end-of-treatment and, most importantly the sustained virological response,i.e. the enlpoint of therapy.

  2. Influenza Round Table: Antiviral Drugs

    Centers for Disease Control (CDC) Podcasts

    2009-11-04

    In this podcast, Dr. Joe Bresee explains the nature of antiviral drugs and how they are used.  Created: 11/4/2009 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 11/4/2009.

  3. Interchromosomal huddle kickstarts antiviral defense.

    Science.gov (United States)

    Schoenfelder, Stefan; Fraser, Peter

    2008-07-11

    Long-distance chromosomal interactions are emerging as a potential mechanism of gene expression control. In this issue, Apostolou and Thanos (2008) describe how viral infection elicits interchromosomal associations between the interferon-beta (IFN-beta) gene enhancer and DNA binding sites of the transcription factor NF-kappaB, resulting in the initiation of transcription and an antiviral response.

  4. The future of antiviral immunotoxins

    DEFF Research Database (Denmark)

    Spiess, K.; Høy Jakobsen, Mette; Kledal, Thomas N;

    2016-01-01

    There is a constant need for new therapeutic interventions in a wide range of infectious diseases. Over the past few years, the immunotoxins have entered the stage as promising antiviral treatments. Immunotoxins have been extensively explored in cancer treatment and have achieved FDA approval...

  5. Orientation and density control of bispecific anti-HER2 antibody on functionalized carbon nanotubes for amplifying effective binding reactivity to cancer cells

    Science.gov (United States)

    Kim, Hye-In; Hwang, Dobeen; Jeon, Su-Ji; Lee, Sangyeop; Park, Jung Hyun; Yim, Dabin; Yang, Jin-Kyoung; Kang, Homan; Choo, Jaebum; Lee, Yoon-Sik; Chung, Junho; Kim, Jong-Ho

    2015-03-01

    Nanomaterial bioconjugates have gained unabated interest in the field of sensing, imaging and therapy. As a conjugation process significantly affects the biological functions of proteins, it is crucial to attach them to nanomaterials with control over their orientation and the nanomaterial-to-protein ratio in order to amplify the binding efficiency of nanomaterial bioconjugates to targets. Here, we describe a targeting nanomaterial platform utilizing carbon nanotubes functionalized with a cotinine-modified dextran polymer and a bispecific anti-HER2 × cotinine tandem antibody. This new approach provides an effective control over antibody orientation and density on the surface of carbon nanotubes through site-specific binding between the anti-cotinine domain of the bispecific tandem antibody and the cotinine group of the functionalized carbon nanotubes. The developed synthetic carbon nanotube/bispecific tandem antibody conjugates (denoted as SNAs) show an effective binding affinity against HER2 that is three orders of magnitude higher than that of the carbon nanotubes bearing a randomly conjugated tandem antibody prepared by carbodiimide chemistry. As the density of a tandem antibody on SNAs increases, their effective binding affinity to HER2 increases as well. SNAs exhibit strong resonance Raman signals for signal transduction, and are successfully applied to the selective detection of HER2-overexpressing cancer cells.Nanomaterial bioconjugates have gained unabated interest in the field of sensing, imaging and therapy. As a conjugation process significantly affects the biological functions of proteins, it is crucial to attach them to nanomaterials with control over their orientation and the nanomaterial-to-protein ratio in order to amplify the binding efficiency of nanomaterial bioconjugates to targets. Here, we describe a targeting nanomaterial platform utilizing carbon nanotubes functionalized with a cotinine-modified dextran polymer and a bispecific anti-HER2

  6. Antibody reactivity to conserved linear epitopes of Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1)

    DEFF Research Database (Denmark)

    Staalsø, T; Khalil, E A; Elhassan, I M;

    1998-01-01

    The Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family of protein antigens are involved in adhesion of P. falciparum infected erythrocytes to the capillary endothelium of the host. Antibodies to variable regions of these proteins, measured by agglutination, correlates with clini......The Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family of protein antigens are involved in adhesion of P. falciparum infected erythrocytes to the capillary endothelium of the host. Antibodies to variable regions of these proteins, measured by agglutination, correlates...

  7. Social stress in male mice impairs long-term antiviral immunity selectively in wounded subjects

    NARCIS (Netherlands)

    de Groot, Johanna; Boersma, Wim J.A.; Scholten, Jan Willem; Koolhaas, Jaap M.

    2002-01-01

    An important property of the antiviral immune response is its time-dependent character. Beginning with a few antigen-specific cells upon infection, it evolves to a stage where there is an abundance of antigen-specific cells and antibodies that are needed to clear the pathogen, and ends with circulat

  8. Structure and function of broadly reactive antibody PG16 reveal an H3 subdomain that mediates potent neutralization of HIV-1

    Energy Technology Data Exchange (ETDEWEB)

    Pejchal, Robert; Walker, Laura M.; Stanfield, Robyn L.; Phogat, Sanjay K.; Koff, Wayne C.; Poignard, Pascal; Burton, Dennis R.; Wilson, Ian A. (Scripps); (IAVI)

    2010-11-15

    Development of an effective vaccine against HIV-1 will likely require elicitation of broad and potent neutralizing antibodies against the trimeric surface envelope glycoprotein (Env). Monoclonal antibodies (mAbs) PG9 and PG16 neutralize {approx}80% of HIV-1 isolates across all clades with extraordinary potency and target novel epitopes preferentially expressed on Env trimers. As these neutralization properties are ideal for a vaccine-elicited antibody response to HIV-1, their structural basis was investigated. The crystal structure of the antigen-binding fragment (Fab) of PG16 at 2.5 {angstrom} resolution revealed its unusually long, 28-residue, complementarity determining region (CDR) H3 forms a unique, stable subdomain that towers above the antibody surface. A 7-residue 'specificity loop' on the 'hammerhead' subdomain was identified that, when transplanted from PG16 to PG9 and vice versa, accounted for differences in the fine specificity and neutralization of these two mAbs. The PG16 electron density maps also revealed that a CDR H3 tyrosine was sulfated, which was confirmed for both PG9 (doubly) and PG16 (singly) by mass spectral analysis. We further showed that tyrosine sulfation plays a role in binding and neutralization. An N-linked glycan modification is observed in the variable light chain, but not required for antigen recognition. Further, the crystal structure of the PG9 light chain at 3.0 {angstrom} facilitated homology modeling to support the presence of these unusual features in PG9. Thus, PG9 and PG16 use unique structural features to mediate potent neutralization of HIV-1 that may be of utility in antibody engineering and for high-affinity recognition of a variety of therapeutic targets.

  9. Detection of Campylobacter species using monoclonal antibodies

    Science.gov (United States)

    Young, Colin R.; Lee, Alice; Stanker, Larry H.

    1999-01-01

    A panel of species specific monoclonal antibodies were raised to Campylobacter coli, Campylobacter jejuni and Campylobacter lari. The isotypes, and cross-reactivity profiles of each monoclonal antibody against an extensive panel of micro- organisms, were determined.

  10. Recent advances in antiviral therapy.

    OpenAIRE

    Kinchington, D

    1999-01-01

    In the early 1980s many institutions in Britain were seriously considering whether there was a need for specialist departments of virology. The arrival of HIV changed that perception and since then virology and antiviral chemotherapy have become two very active areas of bio-medical research. Cloning and sequencing have provided tools to identify viral enzymes and have brought the day of the "designer drug" nearer to reality. At the other end of the spectrum of drug discovery, huge numbers of ...

  11. [Renal toxicity of antiviral drugs].

    Science.gov (United States)

    Frasca', Giovanni M; Balestra, Emilio; Tavio, Marcello; Morroni, Manrico; Manarini, Gloria; Brigante, Fabiana

    2012-01-01

    Highly effective and powerful antiviral drugs have been introduced into clinical practice in recent years which are associated with an increased incidence of nephrotoxicity. The need of combining several drugs, the fragility of the patients treated, and the high susceptibility of the kidney are all factors contributing to renal injury. Many pathogenetic mechanisms are involved in the nephrotoxicity of antiviral drugs, including drug interaction with transport proteins in the tubular cell; direct cytotoxicity due to a high intracellular drug concentration; mitochondrial injury; and intrarenal obstruction or stone formation due to the low solubility of drugs at a normal urinary pH. As a result, various clinical pictures may be observed in patients treated with antiviral drugs, ranging from tubular dysfunction (Fanconi syndrome, renal tubular acidosis, nephrogenic diabetes insipidus) to acute renal failure (induced by tubular necrosis or crystal nephropathy) and kidney stones. Careful attention should be paid to prevent renal toxicity by evaluating the glomerular filtration rate before therapy and adjusting the drug dosage accordingly, avoiding the combination with other nephrotoxic drugs, and monitoring renal parameters on a regular basis while treating patients.

  12. SERUM HIGH SENSITIVE C-REACTIVE PROTEIN AND ANTICARDIOLIPIN ANTIBODY LEVEL IN CAD PATIENTS WITH AND WITHOUT TYPE 2 DIABETES MELLITUS.

    Directory of Open Access Journals (Sweden)

    Sachu Philip

    2012-08-01

    Full Text Available The increased incidence of coronary artery disease (CAD in Type 2 Diabetes mellitus is not fully explained by the conventional risk factors. Our aim was to determine the association of biomarkers, high sensitive CRP and anticardiolipin antibody (acL with severity of coronary artery disease in patients with and without type 2 DM. In our study, hsCRP level was significantly high in CAD with DM and found to be positively correlated with severity (p<0.01 while anticardiolipin antibody does not show any significant change among the two groups. Our study concluded that increased risk of CAD in type 2 DM patients is not only because of dyslipidemia but inflammatory events also play a major role. hsCRP was found to be a valuable predictor for CAD in type 2 DM.

  13. ANTIVIRAL POTENTIAL OF MEDICINAL PLANTS: AN OVERVIEW

    Directory of Open Access Journals (Sweden)

    Ruwali Pushpa

    2013-06-01

    Full Text Available The term ‘Antiviral agents’ has been defined in very broad terms as substances other than a virus or virus containing vaccine or specific antibody which can produce either a protective or therapeutic effect to the clear detectable advantage of the virus infected host. The herbal medicine has a long traditional use and the major advantage over other medicines is their wide therapeutic window with rare side effects. There are some disadvantages of synthetic drugs like narrow therapeutic window and more importantly the various adverse side effects which occur quite frequently. Due to these disadvantages and other limitations, there is an increasing trend in the field of research for discovering new and noble drugs based on various herbal formulations. This review attempts to address the importance of developing therapeutic herbal formulations from various medicinal plants using the knowledge based on traditional system of medicines, the Ayurveda. Although natural products have been used by civilization since ancient times, only in recent decades has there been growing research into alternative therapies and the therapeutics use of natural products, especially those derived from plants. Plants synthesize and preserve a variety of biochemical products, many of which are extractable and used for various scientific investigations. Therefore, medicinal plants proved to be a major resort for the treatment of diseases and sicknesses by traditional healers in many societies.

  14. Thyroid Antibodies

    Science.gov (United States)

    ... AACC products and services. Advertising & Sponsorship: Policy | Opportunities Thyroid Antibodies Share this page: Was this page helpful? Also known as: Thyroid Autoantibodies; Antithyroid Antibodies; Antimicrosomal Antibody; Thyroid Microsomal Antibody; ...

  15. The potential of antiviral agents to control classical swine fever: a modelling study.

    Science.gov (United States)

    Backer, Jantien A; Vrancken, Robert; Neyts, Johan; Goris, Nesya

    2013-09-01

    Classical swine fever (CSF) represents a continuous threat to pig populations that are free of disease without vaccination. When CSF virus is introduced, the minimal control strategy imposed by the EU is often insufficient to mitigate the epidemic. Additional measures such as preemptive culling encounter ethical objections, whereas emergency vaccination leads to prolonged export restrictions. Antiviral agents, however, provide instantaneous protection without inducing an antibody response. The use of antiviral agents to contain CSF epidemics is studied with a model describing within- and between-herd virus transmission. Epidemics are simulated in a densely populated livestock area in The Netherlands, with farms of varying sizes and pig types (finishers, piglets and sows). Our results show that vaccination and/or antiviral treatment in a 2 km radius around an infected herd is more effective than preemptive culling in a 1 km radius. However, the instantaneous but temporary protection provided by antiviral treatment is slightly less effective than the delayed but long-lasting protection offered by vaccination. Therefore, the most effective control strategy is to vaccinate animals when allowed (finishers and piglets) and to treat with antiviral agents when vaccination is prohibited (sows). As independent control measure, antiviral treatment in a 1 km radius presents an elevated risk of epidemics running out of control. A 2 km control radius largely eliminates this risk.

  16. Antiviral immunity following smallpox virus infection: a case-control study.

    Science.gov (United States)

    Hammarlund, Erika; Lewis, Matthew W; Hanifin, Jon M; Mori, Motomi; Koudelka, Caroline W; Slifka, Mark K

    2010-12-01

    Outbreaks of smallpox (i.e., caused by variola virus) resulted in up to 30% mortality, but those who survived smallpox infection were regarded as immune for life. Early studies described the levels of neutralizing antibodies induced after infection, but smallpox was eradicated before contemporary methods for quantifying T-cell memory were developed. To better understand the levels and duration of immunity after smallpox infection, we performed a case-control study comparing antiviral CD4(+) and CD8(+) T-cell responses and neutralizing antibody levels of 24 smallpox survivors with the antiviral immunity observed in 60 smallpox-vaccinated (i.e., vaccinia virus-immune) control subjects. We found that the duration of immunity following smallpox infection was remarkably similar to that observed after smallpox vaccination, with antiviral T-cell responses that declined slowly over time and antiviral antibody responses that remained stable for decades after recovery from infection. These results indicate that severe, potentially life-threatening disease is not required for the development of sustainable long-term immunity. This study shows that the levels of immunity induced following smallpox vaccination are comparable in magnitude to that achieved through natural variola virus infection, and this may explain the notable success of vaccination in eradicating smallpox, one of the world's most lethal diseases.

  17. Antiviral Immunity following Smallpox Virus Infection: a Case-Control Study▿

    Science.gov (United States)

    Hammarlund, Erika; Lewis, Matthew W.; Hanifin, Jon M.; Mori, Motomi; Koudelka, Caroline W.; Slifka, Mark K.

    2010-01-01

    Outbreaks of smallpox (i.e., caused by variola virus) resulted in up to 30% mortality, but those who survived smallpox infection were regarded as immune for life. Early studies described the levels of neutralizing antibodies induced after infection, but smallpox was eradicated before contemporary methods for quantifying T-cell memory were developed. To better understand the levels and duration of immunity after smallpox infection, we performed a case-control study comparing antiviral CD4+ and CD8+ T-cell responses and neutralizing antibody levels of 24 smallpox survivors with the antiviral immunity observed in 60 smallpox-vaccinated (i.e., vaccinia virus-immune) control subjects. We found that the duration of immunity following smallpox infection was remarkably similar to that observed after smallpox vaccination, with antiviral T-cell responses that declined slowly over time and antiviral antibody responses that remained stable for decades after recovery from infection. These results indicate that severe, potentially life-threatening disease is not required for the development of sustainable long-term immunity. This study shows that the levels of immunity induced following smallpox vaccination are comparable in magnitude to that achieved through natural variola virus infection, and this may explain the notable success of vaccination in eradicating smallpox, one of the world's most lethal diseases. PMID:20926574

  18. Characterization of the tumor marker muc16 (ca125 expressed by murine ovarian tumor cell lines and identification of a panel of cross-reactive monoclonal antibodies

    Directory of Open Access Journals (Sweden)

    Goodell Cara AR

    2009-06-01

    Full Text Available Abstract Objectives The ovarian tumor marker CA125 is expressed on human MUC16, a cell surface bound mucin that is also shed by proteolytic cleavage. Human MUC16 is overexpressed by ovarian cancer cells. MUC16 facilitates the binding of ovarian tumor cells to mesothelial cells lining the peritoneal cavity. Additionally, MUC16 also is a potent inhibitor of natural killer cell mediated anti-tumor cytotoxic responses. Extensive studies using human as well as murine ovarian tumor cell models are required to clearly define the function of MUC16 in the progression of ovarian tumors. The major objective of this study was to determine if the murine ovarian tumor cells, MOVCAR, express Muc16 and to characterize antibodies that recognize this mucin. Methods RT-PCR analysis was used for detecting the Muc16 message and size exclusion column chromatography for isolating Muc16 produced by MOVCAR cells. Soluble and cell-associated murine Muc16 were analyzed, respectively, by Western blotting and flow cytometry assays using a new panel of antibodies. The presence of N-linked oligosaccharides on murine Muc16 was determined by ConA chromatography. Results We demonstrate that murine Muc16 is expressed by mouse ovarian cancer cells as an ~250 kDa glycoprotein that carries both O-linked and N-linked oligosaccharides. In contrast to human MUC16, the murine ortholog is primarily released from the cells and cannot be detected on the cell surface. Since the released murine Muc16 is not detected by conventional anti-CA125 assays, we have for the first time identified a panel of anti-human MUC16 antibodies that also recognizes the murine counterpart. Conclusion The antibodies identified in this study can be used in future purification of murine Muc16 and exhaustive study of its properties. Furthermore, the initial identification and characterization of murine Muc16 is a vital preliminary step in the development of effective murine models of human ovarian cancer. These

  19. Immunoglobulin G antibody reactivity to a group A Plasmodium falciparum erythrocyte membrane protein 1 and protection from em>P. falciparum malaria

    DEFF Research Database (Denmark)

    Magistrado, Pamela A; Lusingu, John; Vestergaard, Lasse S;

    2007-01-01

    Variant surface antigens (VSA) on the surface of Plasmodium falciparum-infected red blood cells play a major role in the pathogenesis of malaria and are key targets for acquired immunity. The best-characterized VSA belong to the P. falciparum erythrocyte membrane protein 1 (PfEMP1) family. In areas...... where P. falciparum is endemic, parasites causing severe malaria and malaria in young children with limited immunity tend to express semiconserved PfEMP1 molecules encoded by group A var genes. Here we investigated antibody responses of Tanzanians who were 0 to 19 years old to PF11_0008, a group A PfEMP...

  20. Distribution of Ehrlichia chaffeensis (Rickettsiales: Rickettsiaeceae) in Amblyomma americanum in southern Indiana and prevalence of E. chaffeensis--reactive antibodies in white-tailed deer in Indiana and Ohio in 1998.

    Science.gov (United States)

    Irving, R P; Pinger, R R; Vann, C N; Olesen, J B; Steiner, F E

    2000-07-01

    To continue monitoring the prevalence and distribution of Ehrlichia chaffeensis (Rickettsiales: Rickettsiaeceae) in southern Indiana, a total of 498 Amblyomma americanum (L.) ticks (262 adults and 292 nymphs) was collected from five southern Indiana counties during May and June 1998. Ticks were pooled and examined for the presence of E. chaffeensis using nested polymerase chain reaction and primers specific for the 16S rRNA gene of E. chaffeensis. The average minimum infection rate for adult ticks collected in 1998 was 3.8% (ranging from 0 to 7.7% in various counties) as compared with previous average minimum infection rates of 1.6% in 1995 and 4.9% in 1997. None of the pools of A. americanum nymphs tested positive. In addition, blood samples were collected from 325 white-tailed deer taken in Indiana and 327 taken in Ohio in November 1998. Serum samples were tested for the presence of E. chaffeensis-like organisms reactive to antibodies using an indirect immunofluorescence assay (IFA). Antibodies were found in deer from six Indiana counties where infection rates ranged from 42.6 to 66.7% and in four Ohio countries where infection rates ranged from 4.4 to 25%. The results of this study reconfirm that E. chaffeensis is well established in southern Indiana and also provide the first evidence of E. chaffeensis-like organisms infecting white-tailed deer in Ohio, suggesting the need to survey Ohio ticks for the presence of Ehrlichia.

  1. A natural bacterial-derived product, the metalloprotease arazyme, inhibits metastatic murine melanoma by inducing MMP-8 cross-reactive antibodies.

    Directory of Open Access Journals (Sweden)

    Felipe V Pereira

    Full Text Available The increased incidence, high rates of mortality and few effective means of treatment of malignant melanoma, stimulate the search for new anti-tumor agents and therapeutic targets to control this deadly metastatic disease. In the present work the antitumor effect of arazyme, a natural bacterial-derived metalloprotease secreted by Serratia proteomaculans, was investigated. Arazyme significantly reduced the number of pulmonary metastatic nodules after intravenous inoculation of B16F10 melanoma cells in syngeneic mice. In vitro, the enzyme showed a dose-dependent cytostatic effect in human and murine tumor cells, and this effect was associated to the proteolytic activity of arazyme, reducing the CD44 expression at the cell surface, and also reducing in vitro adhesion and in vitro/in vivo invasion of these cells. Arazyme treatment or immunization induced the production of protease-specific IgG that cross-reacted with melanoma MMP-8. In vitro, this antibody was cytotoxic to tumor cells, an effect increased by complement. In vivo, arazyme-specific IgG inhibited melanoma lung metastasis. We suggest that the antitumor activity of arazyme in a preclinical model may be due to a direct cytostatic activity of the protease in combination with the elicited anti-protease antibody, which cross-reacts with MMP-8 produced by tumor cells. Our results show that the bacterial metalloprotease arazyme is a promising novel antitumor chemotherapeutic agent.

  2. Use of synthetic peptides to represent surface-exposed epitopes defined by neutralizing dengue complex- and flavivirus group-reactive monoclonal antibodies on the native dengue type-2 virus envelope glycoprotein.

    Science.gov (United States)

    Falconar, Andrew K I

    2008-07-01

    The reactions of neutralizing monoclonal antibodies (mAbs) that defined dengue virus (DENV) complex, flavivirus subgroup or group neutralizing epitopes were tested against synthetic peptide sequences from domains I, II and III of the envelope (E) glycoproteins of different DENV-2 genotypes/strains. The DENV complex-reactive mAb identified the surface-exposed 304-GKFKV/IVKEIA-313 peptides and the DENV complex-conserved 393-KKGSSIGQ/KM-401 peptides in domain III, which were located adjacently in the native glycoprotein. Both flavivirus group-reactive mAbs reacted most strongly with fusion sequence peptides from domain II when they contained a cysteine (C) by glycine (G) substitution (underlined) (101-WGNGGGLFG-109) to represent the native rotated C side chain. The 393-401 sequence represents a newly identified epitope, present as a highly flexible coil located between the 385 and 393 cell-binding sequence and the 401 and 413 sequence involved in the E glycoprotein homo-trimer formation. The 101-109 sequence containing 105-C by G substitution and the 393-401 sequence are good candidates for diagnostic assays and cross-protection experiments.

  3. Broad-spectrum antiviral therapeutics.

    Directory of Open Access Journals (Sweden)

    Todd H Rider

    Full Text Available Currently there are relatively few antiviral therapeutics, and most which do exist are highly pathogen-specific or have other disadvantages. We have developed a new broad-spectrum antiviral approach, dubbed Double-stranded RNA (dsRNA Activated Caspase Oligomerizer (DRACO that selectively induces apoptosis in cells containing viral dsRNA, rapidly killing infected cells without harming uninfected cells. We have created DRACOs and shown that they are nontoxic in 11 mammalian cell types and effective against 15 different viruses, including dengue flavivirus, Amapari and Tacaribe arenaviruses, Guama bunyavirus, and H1N1 influenza. We have also demonstrated that DRACOs can rescue mice challenged with H1N1 influenza. DRACOs have the potential to be effective therapeutics or prophylactics for numerous clinical and priority viruses, due to the broad-spectrum sensitivity of the dsRNA detection domain, the potent activity of the apoptosis induction domain, and the novel direct linkage between the two which viruses have never encountered.

  4. Meeting report: 4th ISIRV antiviral group conference: Novel antiviral therapies for influenza and other respiratory viruses.

    Science.gov (United States)

    McKimm-Breschkin, Jennifer L; Fry, Alicia M

    2016-05-01

    The International Society for Influenza and other Respiratory Virus Diseases (isirv) held its 4th Antiviral Group Conference at the University of Texas on 2-4 June, 2015. With emerging resistance to the drugs currently licensed for treatment and prophylaxis of influenza viruses, primarily the neuraminidase inhibitor oseltamivir phosphate (Tamiflu) and the M2 inhibitors amantadine and rimantadine, and the lack of effective interventions against other respiratory viruses, the 3-day programme focused on the discovery and development of inhibitors of several virus targets and key host cell factors involved in virus replication or mediating the inflammatory response. Virus targets included the influenza haemagglutinin, neuraminidase and M2 proteins, and both the respiratory syncytial virus and influenza polymerases and nucleoproteins. Therapies for rhinoviruses and MERS and SARS coronaviruses were also discussed. With the emerging development of monoclonal antibodies as therapeutics, the potential implications of antibody-dependent enhancement of disease were also addressed. Topics covered all aspects from structural and molecular biology to preclinical and clinical studies. The importance of suitable clinical trial endpoints and regulatory issues were also discussed from the perspectives of both industry and government. This meeting summary provides an overview, not only for the conference participants, but also for those interested in the current status of antivirals for respiratory viruses.

  5. Var2CSA DBL6-epsilon domain expressed in HEK293 induces limited cross-reactive and blocking antibodies to CSA binding parasites

    Directory of Open Access Journals (Sweden)

    Scherf Artur

    2008-09-01

    Full Text Available Abstract Background Pregnancy-associated malaria (PAM is a serious consequence of Plasmodium falciparum-infected erythrocytes sequestration in the placenta through the adhesion to the placental receptor chondroitin sulfate A (CSA. Although women become resistant to PAM as they acquire transcending inhibitory immunity against CSA-binding parasites, hundreds of thousands of lives could be saved if a prophylactic vaccine targeting the surface proteins of placental parasites could be designed. Recent works point to the variant protein var2CSA as the key target for the development of a pregnancy-associated malaria vaccine. However, designing such a prophylactic vaccine has been hindered by the difficulty in identifying regions of var2CSA that could elicit broadly neutralizing and adhesion-blocking antibodies. Methods Var2CSA is a very large protein with an estimated molecular weight of 350 kDa, and can be divided into six cysteine rich Duffy binding-like domains (DBL. The human embryonic kidney 293 cell line (HEK293 was used to produce secreted soluble recombinant forms of var2CSA DBL domains. The Escherichia coli expression system was also assessed for the domains not expressed or expressed in low amount in the HEK293 system. To investigate whether var2CSA binding DBL domains can induce biologically active antibodies recognizing the native var2CSA and blocking the interaction, mice were immunized with the refolded DBL3-X or the HEK293 secreted DBL6-ε domains. Results Using the HEK293 expression system, DBL1-X, DBL4-ε and DBL6-ε were produced at relatively high levels in the culture supernatant, while DBL3-X and DBL5-ε were produced at much lower levels. DBL2-X and DBL3-X domains were obtained after refolding of the inclusion bodies produced in E. coli. Importantly, mice antisera raised against the recombinant DBL6-ε domain, specifically reacted against the surface of CSA-binding parasites and revealed adhesion blocking activity. Conclusion This

  6. What You Should Know about Flu Antiviral Drugs

    Science.gov (United States)

    ... this? Submit What's this? Submit Button Past Newsletters What You Should Know About Flu Antiviral Drugs Language: ... that can be used to treat flu illness. What are antiviral drugs? Antiviral drugs are prescription medicines ( ...

  7. Utility of a triple antibody cocktail intraurothelial neoplasm-3 (IUN-3-CK20/CD44s/p53) and α-methylacyl-CoA racemase (AMACR) in the distinction of urothelial carcinoma in situ (CIS) and reactive urothelial atypia.

    Science.gov (United States)

    Aron, Manju; Luthringer, Daniel J; McKenney, Jesse K; Hansel, Donna E; Westfall, Danielle E; Parakh, Rugvedita; Mohanty, Sambit K; Balzer, Bonnie; Amin, Mahul B

    2013-12-01

    Urothelial carcinoma in situ (CIS) is a prognostically and therapeutically significant lesion with considerable morphologic overlap with reactive conditions especially in the setting of prior therapy. Various markers including CK20, CD44s, and p53 have been used as an adjunct in making this distinction; however, the utility of these markers in the posttreatment scenario is not fully established. α-Methylacyl-CoA racemase (AMACR) is a tumor-associated marker that is expressed in a subset of high-grade urothelial carcinomas but has not been studied in CIS. This study was undertaken to evaluate the immunoreactivity of CK20, CD44s, and p53 as a triple antibody cocktail intraurothelial neoplasm-3 (IUN-3) in distinguishing CIS from its mimics and to compare its utility with AMACR in the diagnosis of CIS. A total of 135 specimens (7 benign ureters and 128 bladder biopsies-28 reactive, 33 posttherapy reactive, 43 CIS, 24 CIS posttherapy) were included in this study. Immunostaining for p53 (brown, nuclear), CD44s (brown, membranous), and CK20 (red, cytoplasmic and membranous) was performed as a cocktail, and the staining pattern was further classified as: malignant (full-thickness CK20 and/or full-thickness p53 with CD44s negativity), reactive/benign (CK20 limited to the umbrella cell layer, p53 negative, and CD44s positivity ranging from basal to full thickness), and indeterminate (CK20 and p53 positive but not full thickness and/or CD44s positive). AMACR staining was performed in 50 cases. Cytoplasmic staining for AMACR was graded as negative (absent to weak focal staining [<5% cells]) and positive (≥5%). The "IUN-3 malignant" pattern was observed in 84% of cases of CIS without a history of prior therapy and in 71% of the cases of CIS with a history of prior therapy. Cases with posttherapy reactive atypia showed an "IUN-3 reactive" pattern in 84% cases and "IUN-3 indeterminate" pattern in 16% of the cases; the IUN-3 malignant pattern was not identified in any of the

  8. [3H]Azidodantrolene photoaffinity labeling, synthetic domain peptides and monoclonal antibody reactivity identify the dantrolene binding sequence on RyR1

    Energy Technology Data Exchange (ETDEWEB)

    Paul-Pletzer, Kalanethee; Yamamoto, Takeshi; Bhat, Manju B.; Ma, Jianjie; Ikemoto, Noriaki; Jimenez, Leslie S.; Morimoto, Hiromi; Williams, Philip G.; Parness, Jerome

    2002-06-14

    Dantrolene is a drug that suppresses intracellular Ca2+ release from sarcoplasmic reticulum in normal skeletal muscle and is used as a therapeutic agent in individuals susceptible to malignant hyperthermia. Though its precise mechanism of action has not been elucidated, we have identified the N-terminal region (amino acids 1-1400) of the skeletal muscle isoform of the ryanodine receptor (RyR1), the primary Ca2+ release channel in sarcoplasmic reticulum, as a molecular target for dantrolene using the photoaffinity analog [3H]azidodantrolene(1). Here, we demonstrate that heterologously expressed RyR1 retains its capacity to be specifically labeled with [3H]azidodantrolene,indicating that muscle specific factors are not required for this ligand-receptor interaction. Synthetic domain peptides of RyR1, previously shown to affect RyR1 function in vitro and in vivo, were exploited as potential drug binding site mimics and used in photoaffinity labeling experiments. Only DP1 and DP1-2, peptide s containing the amino acid sequence corresponding to RyR1 residues 590-609, were specifically labeled by [3H]azidodantrolene. A monoclonal anti-RyR1 antibody which recognizes RyR1 and its 1400 amino acid N-terminal fragment, recognizes DP1 and DP1-2 in both Western blots and immunoprecipitation assays, and specifically inhibits [3H]azidodantrolene photolabeling of RyR1 and its N-terminal fragment in sarcoplasmic reticulum. Our results indicate that synthetic domain peptides can mimic a native, ligand binding conformation in vitro, and that the dantrolene binding site and the epitope for the monoclonal antibody on RyR1 are equivalent and composed of amino-acids 590-609.

  9. Naphthyridines with Antiviral Activity - A Review.

    Science.gov (United States)

    Singh, Inder P; Kumar, Sanjay; Gupta, Shiv

    2017-01-01

    Naphthyridine scaffold is an important pharmacophore in compounds which have shown various biological activities like antiviral, antimicrobial, anticancer, antiinflammatory and analgesic. This scaffold is also reported to exhibit activity against HIV, HCMV, HSV, HPV and HCV. Antiviral activity displayed by many naphthyridine analogs is in nM range. Only few review articles are available in literature which describe about various biological activities of naphthyridines, but there is no comprehensive compilation particularly for antiviral activities. The objective of this review is to compile the literature on anti-viral activities of naphthyridine analogs. SciFinder, Google Scholar and PubMed database were searched with keyword "naphthyridine" and the references obtained were further sorted using keywords "antihiv", "antiviral" and "virus", separately. References obtained were considered to review the antiviral literature of naphthyridines. Literature search using SciFinder database with different keywords gave several references. Only references of antiviral activities of naphthyridine compounds were reviewed. References to in-silico studies alone or on formulation development or on patents were excluded. This review will be helpful for future researches to design and synthesize naphthyridine analogs with improved antiviral activities. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  10. Melittin-loaded immunoliposomes against viral surface proteins, a new approach to antiviral therapy.

    Science.gov (United States)

    Falco, Alberto; Barrajón-Catalán, Enrique; Menéndez-Gutiérrez, María P; Coll, Julio; Micol, Vicente; Estepa, Amparo

    2013-02-01

    In this study, melittin, a well-characterized pore-forming lytic amphiphilic peptide susceptible to be vehiculized in lipid membranes, has been utilized to study their antiviral properties. For this purpose, an assay based on melittin loaded-immunoliposomes previously described by our group was adapted to antiviral purposes by means of monoclonal antibodies targeting the surface G glycoprotein of the fish viral haemorrhagic septicemia rhabdovirus (VHSV). We also studied the antiviral action of these immunoliposomes in vitro and the results showed that they are capable of inhibiting the VHSV infectivity by 95.2% via direct inactivation of the virus. Furthermore, the inhibition of the infectivity when treatments were added at different times post-infection and the analysis of the infection foci sizes suggested altogether that they also act by reducing the VHSV spread in cell culture and by killing the infected cells which express the G glycoprotein in their plasmatic membranes.

  11. Antiviral activity of ovotransferrin derived peptides.

    Science.gov (United States)

    Giansanti, Francesco; Massucci, M Teresa; Giardi, M Federica; Nozza, Fabrizio; Pulsinelli, Emy; Nicolini, Claudio; Botti, Dario; Antonini, Giovanni

    2005-05-27

    Ovotransferrin and lactoferrin are iron-binding proteins with antiviral and antibacterial activities related to natural immunity, showing marked sequence and structural homologies. The antiviral activity of two hen ovotransferrin fragments DQKDEYELL (hOtrf(219-227)) and KDLLFK (hOtrf(269-301) and hOtrf(633-638)) towards Marek's disease virus infection of chicken embryo fibroblasts is reported here. These fragments have sequence homology with two bovine lactoferrin fragments with antiviral activity towards herpes simplex virus, suggesting that these fragments could have a role for the exploitation of the antiviral activity of the intact proteins towards herpes viruses. NMR analysis showed that these peptides, chemically synthetized, did not possess any favourite conformation in solution, indicating that both the aminoacid sequence and the conformation they display in the intact protein are essential for the antiviral activity.

  12. Hepatitis C Virus and Antiviral Drug Resistance

    Science.gov (United States)

    Kim, Seungtaek; Han, Kwang-Hyub; Ahn, Sang Hoon

    2016-01-01

    Since its discovery in 1989, hepatitis C virus (HCV) has been intensively investigated to understand its biology and develop effective antiviral therapies. The efforts of the previous 25 years have resulted in a better understanding of the virus, and this was facilitated by the development of in vitro cell culture systems for HCV replication. Antiviral treatments and sustained virological responses have also improved from the early interferon monotherapy to the current all-oral regimens using direct-acting antivirals. However, antiviral resistance has become a critical issue in the treatment of chronic hepatitis C, similar to other chronic viral infections, and retreatment options following treatment failure have become important questions. Despite the clinical challenges in the management of chronic hepatitis C, substantial progress has been made in understanding HCV, which may facilitate the investigation of other closely related flaviviruses and lead to the development of antiviral agents against these human pathogens. PMID:27784846

  13. Mapping the binding site of a cross-reactive Plasmodium falciparum PfEMP1 monoclonal antibody inhibitory of ICAM-1 binding

    DEFF Research Database (Denmark)

    Lennartz, Frank; Bengtsson, Anja; Olsen, Rebecca W

    2015-01-01

    The virulence of Plasmodium falciparum is linked to the ability of infected erythrocytes (IE) to adhere to the vascular endothelium, mediated by P. falciparum erythrocyte membrane protein 1 (PfEMP1). In this article, we report the functional characterization of an mAb that recognizes a panel of Pf......EMP1s and inhibits ICAM-1 binding. The 24E9 mouse mAb was raised against PFD1235w DBLβ3_D4, a domain from the group A PfEMP1s associated with severe malaria. 24E9 recognizes native PfEMP1 expressed on the IE surface and shows cross-reactivity with and cross-inhibition of the ICAM-1 binding capacity...

  14. Ad35 and ad26 vaccine vectors induce potent and cross-reactive antibody and T-cell responses to multiple filovirus species.

    Directory of Open Access Journals (Sweden)

    Roland Zahn

    Full Text Available Filoviruses cause sporadic but highly lethal outbreaks of hemorrhagic fever in Africa in the human population. Currently, no drug or vaccine is available for treatment or prevention. A previous study with a vaccine candidate based on the low seroprevalent adenoviruses 26 and 35 (Ad26 and Ad35 was shown to provide protection against homologous Ebola Zaire challenge in non human primates (NHP if applied in a prime-boost regimen. Here we have aimed to expand this principle to construct and evaluate Ad26 and Ad35 vectors for development of a vaccine to provide universal filovirus protection against all highly lethal strains that have caused major outbreaks in the past. We have therefore performed a phylogenetic analysis of filovirus glycoproteins to select the glycoproteins from two Ebola species (Ebola Zaire and Ebola Sudan/Gulu,, two Marburg strains (Marburg Angola and Marburg Ravn and added the more distant non-lethal Ebola Ivory Coast species for broadest coverage. Ad26 and Ad35 vectors expressing these five filovirus glycoproteins were evaluated to induce a potent cellular and humoral immune response in mice. All adenoviral vectors induced a humoral immune response after single vaccination in a dose dependent manner that was cross-reactive within the Ebola and Marburg lineages. In addition, both strain-specific as well as cross-reactive T cell responses could be detected. A heterologous Ad26-Ad35 prime-boost regime enhanced mainly the humoral and to a lower extend the cellular immune response against the transgene. Combination of the five selected filovirus glycoproteins in one multivalent vaccine potentially elicits protective immunity in man against all major filovirus strains that have caused lethal outbreaks in the last 20 years.

  15. Antimitochondrial antibody

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003529.htm Antimitochondrial antibody To use the sharing features on this page, please enable JavaScript. Antimitochondrial antibodies (AMA) are substances ( antibodies ) that form against mitochondria. ...

  16. Antiviral active peptide from oyster

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    An active peptide against herpes virus was isolated from the enzymic hydrolysate of oyster (Crassostrea gigas) and purified with the definite direction hydrolysis technique in the order of alcalase and bromelin. The hydrolysate was fractioned into four ranges of molecular weight (>10 kDa, 10-5 kDa, 5-1 kDa and <1 kDa) using ultrafiltration membranes and dialysis. The fraction of 10?5 kDa was purified using consecutive chromatographic methods including DEAE Sephadex A-25 column, Sephadex G-25 column, and high performance liquid chromatogram (HPLC) by activity-guided isolation. The antiviral effect of the obtained peptide on herpetic virus was investigated in Vero cells by observing cytopathic effect (CPE). The result shows that the peptide has high inhibitory activity on herpetic virus.

  17. Antiviral Perspectives for Chikungunya Virus

    Directory of Open Access Journals (Sweden)

    Deepti Parashar

    2014-01-01

    Full Text Available Chikungunya virus (CHIKV is a mosquito-borne pathogen that has a major health impact in humans and causes acute febrile illness in humans accompanied by joint pains and, in many cases, persistent arthralgia lasting for weeks to years. CHIKV reemerged in 2005-2006 in several parts of the Indian Ocean islands and India after a gap of 32 years, causing millions of cases. The re-emergence of CHIKV has also resulted in numerous outbreaks in several countries in the eastern hemisphere, with a threat to further expand in the near future. However, there is no vaccine against CHIKV infection licensed for human use, and therapy for CHIKV infection is still mainly limited to supportive care as antiviral agents are yet in different stages of testing or development. In this review we explore the different perspectives for chikungunya treatment and the effectiveness of these treatment regimens and discuss the scope for future directions.

  18. Rapid Purification of a New Humanized Single-chain Fv Antibody/Human Interleukin-2 Fusion Protein Reactive against HER2 Receptor

    Institute of Scientific and Technical Information of China (English)

    Wei-Yun ZHANG; Tak-Chun YIP; Cheuk-Sang KWOK

    2004-01-01

    Human embryonic kidney 293 cells were transfected with plasmid pcDNA-H520C9scFv-rhIL2 containing a chimeric cDNA encoding the humanized 520C9 scFv/recombinant human IL-2 fusion protein (H520C9scFv-rhIL-2). The transfected cells in plateau growing phase were cultured in serum-free medium for three days. The supernatant was collected, concentrated and purified using an affinity column packed with CNBr-activated Sepharose 4B coupled with anti-rhIL-2 mouse monoclonal antibody. The purified fusion protein was analyzed by ELISA, SDS-PAGE and Western blot. The fusion protein showed only one band in both silver stained electrophoresis gel and Western blot developed by ECL chemiluminescence system.Its molecular weight was confirmed to be about 45 kD. This fusion protein possessed binding specificity against p 185 positive SKOV3 and B 16/neu cells, and it might stimulate IL-2-dependent CTLL-2 cell proliferation as well.

  19. Antioxidant, antifungal and antiviral activities of chitosan from the larvae of housefly, Musca domestica L.

    Science.gov (United States)

    Ai, Hui; Wang, Furong; Xia, Yuqian; Chen, Xiaomin; Lei, Chaoliang

    2012-05-01

    Antioxidant activity of the chitosan from the larvae of Musca domestica L. was evaluated in two different reactive oxygen species assays, and inhibitory effects against seven fungi were also tested. The results showed that the chitosan had scavenging activity for hydroxyl and superoxide radicals which were similar to that of ascorbic acid. Also the chitosan exhibited excellent antifungal activity, especially in the low concentration, it could significantly inhibit the growth of Rhizopus stolonifer. Besides, antiviral results demonstrated that the chitosan could effectively inhibit the infection of AcMNPV and BmNPV. These results suggested that the chitosan from the larvae of housefly could be effectively used as a natural antioxidant to protect the human body from free radicals and retard the progress of many chronic diseases. Furthermore, the chitosan with antiviral and antifungal activity might provide useful information for antiviral breeding technology of economic insect and development of plant pathological control.

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

    Directory of Open Access Journals (Sweden)

    Silvia Catellani

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

  1. 化学发光检测梅毒特异性抗体反应性结果分析%Reactive results of Treponema pallidum antibody in chemiluminescent assay

    Institute of Scientific and Technical Information of China (English)

    顾春瑜; 刘刚; 赵乔妹; 李少增; 于勇

    2011-01-01

    Objective To find the cause of false positive results during the detection of Treponema pallidum antibody(TP) in chemiluminescent assay. Methods We put 129 TP reactive samples to chemiluminscent assay, reexamined them by treponema pallidum hemaglutination assay (TPHA) before comparing them. Results When cut - off S/CO was 1, the difference was significant, but there was no significant difference when cut - off S/CO was 5. Conclusions When anti - TP is reactive, especially in the samples of low S/CO value(1.0 -5.0), multiple factors should be taken into consideration, such as age, history of disease, and clinical symptoms , followed by re - examination of the sample by other means. In this way, the chance of false positivity will be reduced.%目的 分析梅毒特异性抗体(treponema pallidum antibody,TP)的有反应性结果,尤其是COI值较低的标本,为减少假阳性的发生提供依据.方法 选取129例用化学发光法检测梅毒特异性抗体有反应性的术前筛查标本,用梅毒螺旋体血凝试剂盒(treponema pallidum hemaglutination assay,TPHA)进行复检,分析比对两者的结果.结果 当切点S/CO值为5时,Syphilis TP阳性为96例,阴性为33例,两种方法差异无统计学意义(P>0.05).结论 当TP有反应性时(尤其是S/CO值为1.0 ~5.0的标本),要综合考虑患者的年龄、病史,以及临床表现,可再用TPHA做复检,如两者均为阳性再报阳性,这样大大减少了假阳性的发生,降低了医疗纠纷的可能.

  2. Application of monoclonal antibody against granulocytes of scallop Chlamys farreri on granulocytes occurrence at different developmental stages and antigenic cross-reactivity of granulocytes in five other bivalve species.

    Science.gov (United States)

    Xing, Jing; Tang, Xiaoqian; Ni, Yongqing; Zhan, Wenbin

    2014-01-01

    A monoclonal antibody (MAb) 6H7 raised specifically against granulocytes of scallop (Chlamys farreri) was employed to observe granulocyte occurrence successively in blastulae, gastrulae, trochophore larvae, D-shape larvae, umbo-veliger larvae and creeping larvae of C. farreri by immunohistochemistry assay contrasted with H&E stain using semi-thin sections. Moreover, the reactivity of the MAb with granulocytes of C. farreri, Bay scallop Argopecten irradians, Japanese scallop Patinopecten yessoensis, Blue mussel Mytilus edulis, Pacific oyster Crassostrea gigas and Manila clam Ruditapes philippinarum, was detected by immunofluorescence assay (IFA) with differential interference contrast and fluorescent microscopy and flow cytometric immunofluorescence assay (FCIFA). The results showed that positive signals were first observed at D-shape larval stage, about 28 h post fertilization, after that, umbo-veliger larvae exhibited the positive cells with a diameter of 3-5 μm distributed in velum, digestive gland and esophagus. Then in creeping larvae, the number of positive cells increased with average diameter of 5-7 μm, and widely distributed in foot, digestive gland, gills and adductor muscles. No positive signal was found in blastulae, gastrulae and trochophore larvae. The results of IFA and FCIFA showed MAb 6H7 reacted to granulocytes of C. farreri, A. irradians, P. yessoensis and C. gigas, and the positive percentage reactivity were 53 ± 2.5%, 15 ± 2.5%, 12 ± 2.1% and 19 ± 2.1%, respectively, however, no cross-reaction was detected in hemocytes of R. philippinarum and M. edulis.

  3. Enhanced reactivity of Alz-50 antibody in brains of sudden infant death syndrome victims versus brains with lethal hypoxic/ischemic injury. Diagnostic significance after application of the ImmunoMax technique on routine paraffin material.

    Science.gov (United States)

    Oehmichen, M; Theuerkauf, I; Bajanowski, T; Merz, H; Meissner, C

    1998-03-01

    Alz-50 antibody is immunoreactive with brain tissue of subjects with Alzheimer's disease and can also be demonstrated by immunocytochemistry in neurons of vibratome-prepared brain tissue of victims of sudden infant death syndrome (SIDS). The application of a slightly modified ImmunoMax method enabled us to demonstrate Alz-50 immunoreactivity in paraffin-embedded material. The Alz-50 epitope was detected in the hippocampus region and in nuclei of the medulla oblongata at the level of the inferior olivary protuberance in three diagnostic groups: victims of SIDS (n = 10), infants dying of subacute hypoxia/ischemia with subsequent (re-)perfusion (n = 9), and infants dying of acute ischemia without (re-) perfusion (n = 7). Quantitative evaluation of the hippocampal cortex and the nucleus olivaris inferior disclosed a significantly (P < 0.05) higher percentage of Alz-50-reactive neurons in SIDS cases than in the control groups (hippocampal cortex and the nucleus olivaris; SIDS victims: median = 100%; subacute hypoxia/ischemia: median = 33.6-81%; acute ischemia: median = 89.2-99%). Semiquantitative analysis revealed an equally pronounced preponderance of Alz-50-reactive neurons in SIDS victims versus the control groups. This greater expression in SIDS victims may be due to an ongoing hypoxia/ischemia during agony, but the present paucity of knowledge prohibits definitive elucidation. Nevertheless, the method described here appears to offer the realistic possibility of distinguishing SIDS cases from cases of sudden death in infants due to other causes, i.e., it offers for the first time a positive criterion for the diagnosis of SIDS.

  4. Production and characterization of monoclonal antibodies against mink leukocytes

    DEFF Research Database (Denmark)

    Chen, W.S.; Pedersen, Mikael; Gram-Nielsen, S.

    1997-01-01

    Three monoclonal antibodies (mAbs) were generated against mink leukocytes. One antibody reacted with all T lymphocytes, one with all monocytes and one had platelet reactivity. Under reducing conditions, the T lymphocyte reactive antibody immunoprecipitated 18 kDa, 23 kDa, 25 kDa and 32-40 kDa pol...

  5. Oxidative stress correlates with Wolbachia-mediated antiviral protection in Wolbachia-Drosophila associations.

    Science.gov (United States)

    Wong, Zhee Sheen; Brownlie, Jeremy C; Johnson, Karyn N

    2015-05-01

    Wolbachia mediates antiviral protection in insect hosts and is being developed as a potential biocontrol agent to reduce the spread of insect-vectored viruses. Definition of the molecular mechanism that generates protection is important for understanding the tripartite interaction between host insect, Wolbachia, and virus. Elevated oxidative stress was previously reported for a mosquito line experimentally infected with Wolbachia, suggesting that oxidative stress is important for Wolbachia-mediated antiviral protection. However, Wolbachia experimentally introduced into mosquitoes impacts a range of host fitness traits, some of which are unrelated to antiviral protection. To explore whether elevated oxidative stress is associated with antiviral protection in Wolbachia-infected insects, we analyzed oxidative stress of five Wolbachia-infected Drosophila lines. In flies infected with protective Wolbachia strains, hydrogen peroxide concentrations were 1.25- to 2-fold higher than those in paired fly lines cured of Wolbachia infection. In contrast, there was no difference in the hydrogen peroxide concentrations in flies infected with nonprotective Wolbachia strains compared to flies cured of Wolbachia infection. Using a Drosophila mutant that produces increased levels of hydrogen peroxide, we investigated whether flies with high levels of endogenous reactive oxygen species had altered responses to virus infection and found that flies with high levels of endogenous hydrogen peroxide were less susceptible to virus-induced mortality. Taken together, these results suggest that elevated oxidative stress correlates with Wolbachia-mediated antiviral protection in natural Drosophila hosts.

  6. Clinical Implications of Antiviral Resistance in Influenza

    OpenAIRE

    Li, Timothy C. M.; Chan, Martin C. W.; Nelson Lee

    2015-01-01

    Influenza is a major cause of severe respiratory infections leading to excessive hospitalizations and deaths globally; annual epidemics, pandemics, and sporadic/endemic avian virus infections occur as a result of rapid, continuous evolution of influenza viruses. Emergence of antiviral resistance is of great clinical and public health concern. Currently available antiviral treatments include four neuraminidase inhibitors (oseltamivir, zanamivir, peramivir, laninamivir), M2-inibitors (amantadin...

  7. 白念珠菌与LDH抗体的交叉免疫研究%Cross-reactive immune response of Candida albicans with anti-LDH antibody

    Institute of Scientific and Technical Information of China (English)

    钟毅; 黄怀球; 赵静; 袁立燕; 张静; 张晓辉; 李美荣

    2012-01-01

    To identify the conserved epitopes of Candida albicans malate dehydrogenase (CaMDH), the structure, function and phylogenetic analysis of the CaMDH sequence were predicted by using tools of bioinformatics. The phylogenetic a-nalysis showed the amino acid sequence of Schistosoma japonic um lactic dehydrogenase (SjLDH) had lowest identity (18. 2%) with CaMDH than that of other species (43%). The structure prediction result showed that CaMDH contained LDH conserved domain and 7 main B cell epitopes, in which 3 epitopes displayed high levels of similarity with that of SjI.DH. The MDH active site located at the NAD (P) binding domain. Furthermore, the Sj'LDH recombinant protein immune serum which had lowest i-dentity with CaMDH in study was chosen to make cross-reactive immune response with Candida albicans protein. The positive result with the anti-LDH body identify that the interaction point was highly conserved epitopes of CaMDH homologous sequence and supply new methods for the vaccine, diagnosis and drug target study of the CaMDH.%目的 识别白念珠菌苹果酸脱氢酶(Candida albicans malate dehydrogenase,CaMDH)保守表位结构.方法 本研究利用生物信息学方法,预测CaMDH的结构、功能和进化关系,并选取同源序列中与CaMDH序列一致性较低的日本血吸虫乳酸脱氢酶(Schistosoma japonicum lactate dehydrogenase,SjLDH)免疫血清与白念珠菌总蛋白进行交叉免疫反应.结果 发现CaMDH与常见病原生物的同源序列一致性可达43%,其中与SjLDH一致性最低(18.2%).CaMDH具有乳酸脱氢酶保守区域,7个主要的B细胞表位,其中3处与SjLDH表位相似.苹果酸脱氢酶活化点包含于NAD(P)结合部分中.白念珠菌总蛋白与SjLDH免疫血清交叉免疫反应阳性.结论 交叉免疫反应阳性提示识别结合位点为LDH/MDH同源序列高度保守的表位结构,为进一步从高度保守的抗原决定簇中筛选真菌疫苗表位、诊断特异抗体、抗真菌药物治疗靶点提供了实验基础.

  8. Silver Nanoparticles as Potential Antiviral Agents

    Directory of Open Access Journals (Sweden)

    Massimiliano Galdiero

    2011-10-01

    Full Text Available Virus infections pose significant global health challenges, especially in view of the fact that the emergence of resistant viral strains and the adverse side effects associated with prolonged use continue to slow down the application of effective antiviral therapies. This makes imperative the need for the development of safe and potent alternatives to conventional antiviral drugs. In the present scenario, nanoscale materials have emerged as novel antiviral agents for the possibilities offered by their unique chemical and physical properties. Silver nanoparticles have mainly been studied for their antimicrobial potential against bacteria, but have also proven to be active against several types of viruses including human imunodeficiency virus, hepatitis B virus, herpes simplex virus, respiratory syncytial virus, and monkey pox virus. The use of metal nanoparticles provides an interesting opportunity for novel antiviral therapies. Since metals may attack a broad range of targets in the virus there is a lower possibility to develop resistance as compared to conventional antivirals. The present review focuses on the development of methods for the production of silver nanoparticles and on their use as antiviral therapeutics against pathogenic viruses.

  9. [Antinuclear antibodies].

    Science.gov (United States)

    Cabiedes, Javier; Núñez-Álvarez, Carlos A

    2010-01-01

    Anti-nuclear antibodies (ANA) are immunoglobulin directed against autologous cell nuclear and cytoplasmic components. Besides the autoimmune ANA there are other ANA that can be detected in circulation, like natural and infectious ANA. Because of its high sensibility, detection of the ANA must be done by indirect immunofluorescence (IIF) as screening test and all of those positive samples are convenient to confirm its specificity by ELISA, western blot or other techniques. Positive ANA detected by IIF must be evaluated taking in to account the pattern and titer. The following recommended step is the specificity characterization (reactivity against extractable nuclear antigens [ENA], dsDNA, etc.) which is useful for the diagnosis and follow up of patients with autoimmune diseases, and by such reasoning, its detection must be performed in an orderly and reasonable way using guides or strategies focused to the good use and interpretation of the autoantibodies. The objective of this review is to present a compilation of the literature and our experience in the detection and study of the ANA.

  10. Clinical features and antinuclear antibodies profile among adults ...

    African Journals Online (AJOL)

    Clinical features and antinuclear antibodies profile among adults with ... the clinical manifestations and pattern of Systemic Lupus Erythematosus (SLE) in Sudan. ... SLE reactive antibodies and the histological diagnosis of lupus were studied.

  11. Containing pandemic influenza with antiviral agents.

    Science.gov (United States)

    Longini, Ira M; Halloran, M Elizabeth; Nizam, Azhar; Yang, Yang

    2004-04-01

    For the first wave of pandemic influenza or a bioterrorist influenza attack, antiviral agents would be one of the few options to contain the epidemic in the United States until adequate supplies of vaccine were available. The authors use stochastic epidemic simulations to investigate the effectiveness of targeted antiviral prophylaxis to contain influenza. In this strategy, close contacts of suspected index influenza cases take antiviral agents prophylactically. The authors compare targeted antiviral prophylaxis with vaccination strategies. They model an influenza pandemic or bioterrorist attack for an agent similar to influenza A virus (H2N2) that caused the Asian influenza pandemic of 1957-1958. In the absence of intervention, the model predicts an influenza illness attack rate of 33% of the population (95% confidence interval (CI): 30, 37) and an influenza death rate of 0.58 deaths/1,000 persons (95% Cl: 0.4, 0.8). With the use of targeted antiviral prophylaxis, if 80% of the exposed persons maintained prophylaxis for up to 8 weeks, the epidemic would be contained, and the model predicts a reduction to an illness attack rate of 2% (95% Cl: 0.2, 16) and a death rate of 0.04 deaths/1,000 persons (95% CI: 0.0003, 0.25). Such antiviral prophylaxis is nearly as effective as vaccinating 80% of the population. Vaccinating 80% of the children aged less than 19 years is almost as effective as vaccinating 80% of the population. Targeted antiviral prophylaxis has potential as an effective measure for containing influenza until adequate quantities of vaccine are available.

  12. Antiviral activities of heated dolomite powder.

    Science.gov (United States)

    Motoike, Koichi; Hirano, Shozo; Yamana, Hideaki; Onda, Tetsuhiko; Maeda, Takayoshi; Ito, Toshihiro; Hayakawa, Motozo

    2008-12-01

    The effect of the heating conditions of dolomite powder on its antiviral activity was studied against the H5N3 avian influenza virus. Calcium oxide (CaO) and magnesium oxide (MgO), obtained by the thermal decomposition of dolomite above 800 degrees C, were shown to have strong antiviral activity, but the effect was lessened when the heating temperature exceeded 1400 degrees C. Simultaneous measurement of the crystallite size suggested that the weakening of the activity was due to the considerable grain growth of the oxides. It was found that the presence of Mg in dolomite contributed to the deterrence of grain growth of the oxides during the heating process. Although both CaO and MgO exhibited strong antiviral activity, CaO had the stronger activity but quickly hydrated in the presence of water. On the other hand, the hydration of MgO took place gradually under the same conditions. Separate measurements using MgO and Mg(OH)2 revealed that MgO had a higher antiviral effect than Mg(OH)2. From the overall experiments, it was suggested that the strong antiviral activity of dolomite was related to the hydration reaction of CaO.

  13. 氨苄青霉素单克隆抗体及其与青霉素类抗生素交叉反应性%Anti-ampicillin Monoclonal Antibodies and Their Cross-reactivity to Penicillin Antibiotics

    Institute of Scientific and Technical Information of China (English)

    李青梅; 刘庆堂; 王寅彪; 柴书军; 王自良; 郭军庆; 职爱民; 孟红丽; 张改平

    2011-01-01

    Ampicillin ( Amp) was coupled to carrier proteins of bovine serum albumin ( BSA ) and ovalbumin (OVA) to synthetize immunogen BSA-Amp and detection antigen OVA-Amp. Four hybridoma cell lines secreting monoclonal antibodies (mAbs) specific for Amp were established by immunizing BALB/c mice with BSA-Amp u-sing hybridoma technology. The antibody titers of mAb ascites (1G7, 2A11, 2D10 and 3F6) were determined as 1:2.56×107, 1:1.28×107, 1 :5.12 × 106 and 1:5.12 × 106 in ELISA, and their half maximal inhibitory concentration (IC50) of Amp were 10.22, 3.58, 4.03,4.95 ng/mL in the inhibitive ELISA, respectively. The Amp mAbs showed significant cross-reactivity to the penicillin antibiotics of carbenicillin (1G7, 2A11, 2D10 and 3F6 ) , penicillin G (1G7 and 3F6) , and amoxicillin (1G7) , whereas no obvious cross-reactivity to dicloxacillin or clox-acillin was found.%以戊二醛法将氨苄青霉素(Ampicillin,Amp)偶联于牛血清白蛋白(BSA)和卵清白蛋白(OVA),合成免疫抗原BSA-Amp和检测抗原0VA-Amp,并进行了鉴定;用BSA-Amp免疫BALB/c小鼠,应用杂交瘤技术建立了4株分泌抗Amp单克隆抗体的杂交瘤细胞株.ELISA和竞争ELISA结果显示,单克隆抗体1G7、2A11、2D10和3F6的腹水抗体效价分别为1:2.56×107、1:1.28×107、1:5.12 ×106和1:5.12×106,Amp的半数抑制浓度(IC50)分别为10.22,3.58,4.03,4.95 ng/mL.Amp单克隆抗体与羧苄青霉素(1G7、2A11、2D10和3F6)、青霉素G(1G7和3F6)、阿莫西林(1G7)等青霉素类抗生素存在显著的交叉反应,而与双氯霉素和邻氯霉素未见明显交叉反应.

  14. Immunologically driven chemical engineering of antibodies for catalytic activity.

    Science.gov (United States)

    Dias, Sonia; Jovic, Florence; Renard, Pierre-Yves; Taran, Fréderic; Créminon, Christophe; Mioskowski, Charles; Grassi, Jacques

    2002-11-01

    We describe a new strategy for the preparation of catalytic antibodies based on a two-step procedure. Firstly, monoclonal antibodies are selected only if displaying the following binding features: binding both the substrate and a reactive group in such a way that the two groups are in a reactive position towards each other. Secondly, the selected monoclonal antibodies (mAbs) are chemically engineered by covalently binding the reactive group into the binding pocket of the antibody. Using previously isolated monoclonal antibodies, we have focused our studies on the control of this second step.

  15. A fresh look at an antiviral helicase

    Institute of Scientific and Technical Information of China (English)

    Leonid Gitlin; Marco Colonna

    2007-01-01

    @@ In order to survive,all organlsms must guard against viral infections.Recognition of viruses is accomplished via multiple sensors.Many mammalian proteins can recognize viral products,such as double-stranded RNA(dsRNA),yet feW of them are known to induce interferon,the central antiviral messenger.Since interferon is indispensable for Successful antiviral defense [1],the interferon-inducing sensors have been of particular interest.However,a clear understanding of such sensors has been elusive,and the first well-established sensor family,the toll-like receptors (TLRs),was described relatively recently[2].Antiviral TLRS are positioned in the endosomes,where they report the appearance of viral genetic material(DNA,single-and double-stranded RNA).

  16. Drosophila as a model for antiviral immunity

    Institute of Scientific and Technical Information of China (English)

    Susanna; Valanne; Mika; Rmet

    2010-01-01

    The fruit fly Drosophila melanogaster has been successfully used to study numerous biological processes including immune response.Flies are naturally infected with more than twenty RNA viruses making it a valid model organism to study host-pathogen interactions during viral infections.The Drosophila antiviral immunity includes RNA interference,activation of the JAK/STAT and other signaling cascades and other mechanisms such as autophagy and interactions with other microorganisms.Here we review Drosophila as an immunological research model as well as recent advances in the field ofDrosophila antiviral immunity.

  17. Antibody-Mediated Internalization of Infectious HIV-1 Virions Differs among Antibody Isotypes and Subclasses.

    Science.gov (United States)

    Tay, Matthew Zirui; Liu, Pinghuang; Williams, LaTonya D; McRaven, Michael D; Sawant, Sheetal; Gurley, Thaddeus C; Xu, Thomas T; Dennison, S Moses; Liao, Hua-Xin; Chenine, Agnès-Laurence; Alam, S Munir; Moody, M Anthony; Hope, Thomas J; Haynes, Barton F; Tomaras, Georgia D

    2016-08-01

    Emerging data support a role for antibody Fc-mediated antiviral activity in vaccine efficacy and in the control of HIV-1 replication by broadly neutralizing antibodies. Antibody-mediated virus internalization is an Fc-mediated function that may act at the portal of entry whereby effector cells may be triggered by pre-existing antibodies to prevent HIV-1 acquisition. Understanding the capacity of HIV-1 antibodies in mediating internalization of HIV-1 virions by primary monocytes is critical to understanding their full antiviral potency. Antibody isotypes/subclasses differ in functional profile, with consequences for their antiviral activity. For instance, in the RV144 vaccine trial that achieved partial efficacy, Env IgA correlated with increased risk of HIV-1 infection (i.e. decreased vaccine efficacy), whereas V1-V2 IgG3 correlated with decreased risk of HIV-1 infection (i.e. increased vaccine efficacy). Thus, understanding the different functional attributes of HIV-1 specific IgG1, IgG3 and IgA antibodies will help define the mechanisms of immune protection. Here, we utilized an in vitro flow cytometric method utilizing primary monocytes as phagocytes and infectious HIV-1 virions as targets to determine the capacity of Env IgA (IgA1, IgA2), IgG1 and IgG3 antibodies to mediate HIV-1 infectious virion internalization. Importantly, both broadly neutralizing antibodies (i.e. PG9, 2G12, CH31, VRC01 IgG) and non-broadly neutralizing antibodies (i.e. 7B2 mAb, mucosal HIV-1+ IgG) mediated internalization of HIV-1 virions. Furthermore, we found that Env IgG3 of multiple specificities (i.e. CD4bs, V1-V2 and gp41) mediated increased infectious virion internalization over Env IgG1 of the same specificity, while Env IgA mediated decreased infectious virion internalization compared to IgG1. These data demonstrate that antibody-mediated internalization of HIV-1 virions depends on antibody specificity and isotype. Evaluation of the phagocytic potency of vaccine

  18. Bell's Palsy: Treatment with Steroids and Antiviral Drugs

    Science.gov (United States)

    ... PATIENTS and their FAMILIES BELL’S PALSY: TREATMENT WITH STEROIDS AND ANTIVIRAL DRUGS This information sheet is provided to help you understand the role of steroids and antiviral drugs for treating Bell’s palsy. Neurologists ...

  19. How antibodies use complement to regulate antibody responses.

    Science.gov (United States)

    Sörman, Anna; Zhang, Lu; Ding, Zhoujie; Heyman, Birgitta

    2014-10-01

    Antibodies, forming immune complexes with their specific antigen, can cause complete suppression or several 100-fold enhancement of the antibody response. Immune complexes containing IgG and IgM may activate complement and in such situations also complement components will be part of the immune complex. Here, we review experimental data on how antibodies via the complement system upregulate specific antibody responses. Current data suggest that murine IgG1, IgG2a, and IgG2b upregulate antibody responses primarily via Fc-receptors and not via complement. In contrast, IgM and IgG3 act via complement and require the presence of complement receptors 1 and 2 (CR1/2) expressed on both B cells and follicular dendritic cells. Complement plays a crucial role for antibody responses not only to antigen complexed to antibodies, but also to antigen administered alone. Lack of C1q, but not of Factor B or MBL, severely impairs antibody responses suggesting involvement of the classical pathway. In spite of this, normal antibody responses are found in mice lacking several activators of the classical pathway (complement activating natural IgM, serum amyloid P component (SAP), specific intracellular adhesion molecule-grabbing non-integrin R1 (SIGN-R1) or C-reactive protein. Possible explanations to these observations will be discussed.

  20. Recombinant mouse interferon-gamma regulation of antibody production.

    OpenAIRE

    1983-01-01

    Interferon-gamma produced in monkey cells by transfection with mouse interferon-gamma cDNA suppressed the mouse in vitro antibody response in a manner similar to that of natural mouse interferon-gamma. Significant suppression was obtained with as little as 1 U of interferon. Recombinant human interferon-gamma produced by cloning in a similar fashion was not suppressive. Both the suppressive and the antiviral activities of recombinant interferon-gamma were neutralized by antibodies to mouse na...

  1. Antiviral drug resistance of herpes simplex virus

    NARCIS (Netherlands)

    Stranska, Ruzena

    2004-01-01

    Infections with herpes simplex virus (HSV) usually have an asymptomatic or benign course. However, severe infections do occur, particularly in HIV/AIDS patients or transplant recipients, and may be life-threatening unless adequate antiviral therapy is given. Since its introduction in the early 1980

  2. Antiviral drug resistance of herpes simplex virus

    NARCIS (Netherlands)

    Stranska, Ruzena

    2004-01-01

    Infections with herpes simplex virus (HSV) usually have an asymptomatic or benign course. However, severe infections do occur, particularly in HIV/AIDS patients or transplant recipients, and may be life-threatening unless adequate antiviral therapy is given. Since its introduction in the early

  3. IFN-gamma: Novel antiviral cytokines

    DEFF Research Database (Denmark)

    Ank, Nina; West, Hans; Paludan, Søren Riis

    2006-01-01

    and adaptive immune responses. Recently, a novel class of cytokines was discovered and named IFN-lambda (alternatively type III IFN or interleukin-28/29 [IL- 28/29]), based on IFN-like antiviral activity and induction of typical IFN-inducible genes. Here, we review the literature on IFN-lambda and discuss...

  4. Antiviral Prophylaxis and H1N1

    Centers for Disease Control (CDC) Podcasts

    2011-07-14

    Dr. Richard Pebody, a consultant epidemiologist at the Health Protection Agency in London, UK, discusses the use of antiviral post-exposure prophylaxis and pandemic H1N1.  Created: 7/14/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 7/18/2011.

  5. DMPD: Antiviral innate immunity pathways. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 16474426 Antiviral innate immunity pathways. Seth RB, Sun L, Chen ZJ. Cell Res. 200...6 Feb;16(2):141-7. (.png) (.svg) (.html) (.csml) Show Antiviral innate immunity pathways. PubmedID 16474426 ...Title Antiviral innate immunity pathways. Authors Seth RB, Sun L, Chen ZJ. Publication Cell Res. 2006 Feb;16

  6. Interferon induced IFIT family genes in host antiviral defense

    Science.gov (United States)

    Secretion of interferons (IFNs) from virus-infected cells is a hallmark of host antiviral immunity and in fact, IFNs exert their antiviral activities through the induction of antiviral proteins. The IFN-induced protein with tetratricopeptide repeats (IFITs) family is among hundreds of IF stimulated ...

  7. Antiviral effect of cationic compounds on bacteriophages

    Directory of Open Access Journals (Sweden)

    Mai Huong eChatain-Ly

    2013-03-01

    Full Text Available The antiviral activity of several cationic compounds - cetytrimethylammonium (CTAB, chitosan, nisin and lysozyme - was investigated on the bacteriophage c2 (DNA head and non-contractile tail infecting Lactococcus strains and the bacteriophage MS2 (F-specific RNA infecting E.coli. Firstly, these activities were evaluated in a phosphate buffer pH 7- 10 mM. The CTAB had a virucidal effect on the Lactococcus bacteriophages, but not on the MS2. After 1 min of contact with 0.125 mM CTAB, the c2 population was reduced from 6 log(pfu/mL to 1,5 log(pfu/mL and completely deactivated at 1 mM. On the contrary, chitosan inhibited the MS2 more than it did the bacteriophages c2. No antiviral effect was observed for the nisin or the lysozyme on bacteriophages after 1 min of treatment. A 1 and 2.5 log reduction was respectively observed for nisin and lysozyme when the treatment time increased (5 or 10 min. These results showed that the antiviral effect depended both on the virus and structure of the antimicrobial compounds. The antiviral activity of these compounds was also evaluated in different physico-chemical conditions and in complex matrices. The antiviral activity of CTAB was impaired in acid pH and with an increase of the ionic strength. These results might be explained by the electrostatic interactions between cationic compounds and negatively charged particles such as bacteriophages or other compounds in a matrix. Milk proved to be protective suggesting the components of food could interfere with antimicrobial compounds.

  8. Antibody-Based Strategies to Prevent and Treat Influenza

    Directory of Open Access Journals (Sweden)

    Ram eSasisekharan

    2015-07-01

    Full Text Available Passive immunization using antibodies has been suggested to offer several benefits in comparison to other antiviral treatment options. The potential for seasonal protection arising from a single injection of antibodies is appealing and has been pursued for a number of infectious agents. However, until recently, antibody-based strategies to combat infectious agents has been hampered due to the fact that typical antibodies have been found to be strain-specific, with the virus evolving resistance in many cases. The discovery of broadly neutralizing antibodies (bNAbs in, for example, influenza, dengue virus, and HIV, which bind to multiple, structurally-diverse strains has provided renewed interest in this area. This review will focus on new technologies that enable the discovery of bNAbs, the challenges and opportunities of immunotherapies as an important addition to existing antiviral therapy, and the role of antibody discovery in informing rational vaccine discovery – with agents targeting influenza specifically addressed. Multiple agents have entered the clinic and raise the possibility that a single antibody or small combination of antibodies can effectively neutralize a wide variety of strains. However, challenges remain - including combating escape variants, pharmacodynamics of antibody distribution, and development of efficacy biomarkers beyond virologic endpoints.

  9. TRIM25 Enhances the Antiviral Action of Zinc-Finger Antiviral Protein (ZAP)

    Science.gov (United States)

    Lau, Zerlina; Cheung, Pamela; Schneider, William M.; Bozzacco, Leonia; Buehler, Eugen; Takaoka, Akinori; Rice, Charles M.; Felsenfeld, Dan P.; MacDonald, Margaret R.

    2017-01-01

    The host factor and interferon (IFN)-stimulated gene (ISG) product, zinc-finger antiviral protein (ZAP), inhibits a number of diverse viruses by usurping and intersecting with multiple cellular pathways. To elucidate its antiviral mechanism, we perform a loss-of-function genome-wide RNAi screen to identify cellular cofactors required for ZAP antiviral activity against the prototype alphavirus, Sindbis virus (SINV). In order to exclude off-target effects, we carry out stringent confirmatory assays to verify the top hits. Important ZAP-liaising partners identified include proteins involved in membrane ion permeability, type I IFN signaling, and post-translational protein modification. The factor contributing most to the antiviral function of ZAP is TRIM25, an E3 ubiquitin and ISG15 ligase. We demonstrate here that TRIM25 interacts with ZAP through the SPRY domain, and TRIM25 mutants lacking the RING or coiled coil domain fail to stimulate ZAP’s antiviral activity, suggesting that both TRIM25 ligase activity and its ability to form oligomers are critical for its cofactor function. TRIM25 increases the modification of both the short and long ZAP isoforms by K48- and K63-linked polyubiquitin, although ubiquitination of ZAP does not directly affect its antiviral activity. However, TRIM25 is critical for ZAP’s ability to inhibit translation of the incoming SINV genome. Taken together, these data uncover TRIM25 as a bona fide ZAP cofactor that leads to increased ZAP modification enhancing its translational inhibition activity. PMID:28060952

  10. Establishment of a quantitative ELISA for the measurement of allergen-specific IgE in dogs using anti-IgE antibody cross-reactive to mouse and dog IgE.

    Science.gov (United States)

    Okayama, Taro; Matsuno, Yukiko; Yasuda, Nobutaka; Tsukui, Toshihiro; Suzuta, Yasuyuki; Koyanagi, Masanori; Sakaguchi, Masahiro; Ishii, Yasuyuki; Olivry, Thierry; Masuda, Kenichi

    2011-02-15

    As IgE plays a pivotal role in type I hypersensitivity-mediated allergic diseases, it is valuable to measure absolute quantity of serum antigen-specific IgE for clinical and research purposes. Here we describe a novel ELISA system that enables quantification of antigen-specific IgE in ng/ml in dogs. A newly developed monoclonal antibody (CRE-DM) was shown to recognize canine and mouse IgE equally in a dose dependent manner, but it did not recognize canine IgG. The reactivity of CRE-DM to canine IgE was also confirmed by an inhibition ELISA using canine IgE as an inhibitor and the maximum inhibition rate was 91.3%. In order to know whether canine IgE specific to an allergen could be quantitatively measured with an ELISA using CRE-DM, we established a quantitative ELISA that could measure canine IgE recognizing Cry j 1, one of the major allergens of Japanese cedar pollen. In this ELISA, a standard curve was created by using concentration-predetermined Cry j 1-specific monoclonal mouse IgE. According to the standard curve, the concentration of Cry j 1-specific IgE in dogs that were experimentally sensitized to Japanese cedar pollen could be calculated and determined in ng/ml. The specificity of the Cry j 1-specific IgE ELISA using CRE-DM was also confirmed by inhibition ELISA using canine IgE as an inhibitor and the inhibition rate was 97.0%. Reproducibility of the ELISA in three independent assays was determined using groups of pooled canine sera whose Cry j 1-IgE titers ranged from 155.9 to 888.2 ng/ml. Intra- and inter-assay reproducibility was determined with coefficient of variation ranging between 3.1-5.2% and 2.2-8.0%, respectively. These results demonstrated that the ELISA utilizing CRE-DM was a specific, reliable and robust new laboratory test that could quantify absolute amount of antigen-specific IgE in canine serum. The ELISA will serve as a useful tool in the clinics to evaluate the change of serum IgE titers during anti-allergic treatments as well as

  11. Monoclonal antibodies to intermediate filament proteins of human cells: unique and cross-reacting antibodies.

    Science.gov (United States)

    Gown, A M; Vogel, A M

    1982-11-01

    Monoclonal antibodies were generated against the intermediate filament proteins of different human cells. The reactivity of these antibodies with the different classes of intermediate filament proteins was determined by indirect immunofluorescence on cultured cells, immunologic indentification on SDS polyacrylamide gels ("wester blot" experiments), and immunoperoxidase assays on intact tissues. The following four antibodies are described: (a) an antivimentin antibody generated against human fibroblast cytoskeleton; (b), (c) two antibodies that recognize a 54-kdalton protein in human hepatocellular carcinoma cells; and (d) an antikeratin antibody made to stratum corneum that recognizes proteins of molecular weight 66 kdaltons and 57 kdaltons. The antivimentin antibody reacts with vimentin (58 kdaltons), glial fibrillary acidic protein (GFAP), and keratins from stratum corneum, but does not recognize hepatoma intermediate filaments. In immunofluorescence assays, the antibody reacts with mesenchymal cells and cultured epithelial cells that express vimentin. This antibody decorates the media of blood vessels in tissue sections. One antihepatoma filament antibody reacts only with the 54 kdalton protein of these cells and, in immunofluorescence and immunoperoxidase assays, only recognizes epithelial cells. It reacts with almost all nonsquamous epithelium. The other antihepatoma filament antibody is much less selective, reacting with vimentin, GFAP, and keratin from stratum corneum. This antibody decorates intermediate filaments of both mesenchymal and epithelial cells. The antikeratin antibody recognizes 66-kdalton and 57-kdalton proteins in extracts of stratum corneum and also identifies proteins of similar molecular weights in all cells tested. However, by immunofluorescence, this antibody decorates only the intermediate filaments of epidermoid carcinoma cells. When assayed on tissue sections, the antibody reacts with squamous epithelium and some, but not all

  12. Development of Antibody Against Sulfamethazine

    Institute of Scientific and Technical Information of China (English)

    LIZi-ying; XUWen-ge; LIUYi-bing; ZHANGLi-ling; GUOWei-zheng; HANShi-quan

    2003-01-01

    Polyclonal antibodies(PcAbs) against sulfamethazine(SMT) are obtained by immunizing rabbits with SMT-conjugated bovine serum albumin(BSA). The affinity constants (Ka) of the PcAbs are higher than 1×108 and the cross-reactivities with sulfadiazine(SD), sulfaquinoxaline (SQX) are lower than 0.05% (R/A).

  13. Evaluation of Influenza Virus A/H3N2 and B Vaccines on the Basis of Cross-Reactivity of Postvaccination Human Serum Antibodies against Influenza Viruses A/H3N2 and B Isolated in MDCK Cells and Embryonated Hen Eggs

    Science.gov (United States)

    Kishida, Noriko; Fujisaki, Seiichiro; Yokoyama, Masaru; Sato, Hironori; Saito, Reiko; Ikematsu, Hideyuki; Xu, Hong; Takashita, Emi; Tashiro, Masato; Takao, Shinichi; Yano, Takuya; Suga, Tomoko; Kawakami, Chiharu; Yamamoto, Miwako; Kajiyama, Keiko; Saito, Hiroyuki; Shimada, Shin'ichi; Watanabe, Sumi; Aoki, Satomi; Taira, Katsuya; Kon, Miyako; Lin, Jih-Hui

    2012-01-01

    The vaccine strains against influenza virus A/H3N2 for the 2010-2011 season and influenza virus B for the 2009-2010 and 2010-2011 seasons in Japan are a high-growth reassortant A/Victoria/210/2009 (X-187) strain and an egg-adapted B/Brisbane/60/2008 (Victoria lineage) strain, respectively. Hemagglutination inhibition (HI) tests with postinfection ferret antisera indicated that the antisera raised against the X-187 and egg-adapted B/Brisbane/60/2008 vaccine production strains poorly inhibited recent epidemic isolates of MDCK-grown A/H3N2 and B/Victoria lineage viruses, respectively. The low reactivity of the ferret antisera may be attributable to changes in the hemagglutinin (HA) protein of production strains during egg adaptation. To evaluate the efficacy of A/H3N2 and B vaccines, the cross-reactivities of postvaccination human serum antibodies against A/H3N2 and B/Victoria lineage epidemic isolates were assessed by a comparison of the geometric mean titers (GMTs) of HI and neutralization (NT) tests. Serum antibodies elicited by the X-187 vaccine had low cross-reactivity to both MDCK- and egg-grown A/H3N2 isolates by HI test and narrow cross-reactivity by NT test in all age groups. On the other hand, the GMTs to B viruses detected by HI test were below the marginal level, so the cross-reactivity was assessed by NT test. The serum neutralizing antibodies elicited by the B/Brisbane/60/2008 vaccine reacted well with egg-grown B viruses but exhibited remarkably low reactivity to MDCK-grown B viruses. The results of these human serological studies suggest that the influenza A/H3N2 vaccine for the 2010-2011 season and B vaccine for the 2009-2010 and 2010-2011 seasons may possess insufficient efficacy and low efficacy, respectively. PMID:22492743

  14. Antiviral potential of lactic acid bacteria and their bacteriocins.

    Science.gov (United States)

    Al Kassaa, I; Hober, D; Hamze, M; Chihib, N E; Drider, D

    2014-12-01

    Emerging resistance to antiviral agents is a growing public health concern worldwide as it was reported for respiratory, sexually transmitted and enteric viruses. Therefore, there is a growing demand for new, unconventional antiviral agents which may serve as an alternative to the currently used drugs. Meanwhile, published literature continues shedding the light on the potency of lactic acid bacteria (LAB) and their bacteriocins as antiviral agents. Health-promoting LAB probiotics may exert their antiviral activity by (1) direct probiotic-virus interaction; (2) production of antiviral inhibitory metabolites; and/or (3) via stimulation of the immune system. The aim of this review was to highlight the antiviral activity of LAB and substances they produce with antiviral activity.

  15. Preemptive antiviral therapy with entecavir can reduce acute deterioration of hepatic function following transarterial chemoembolization.

    Science.gov (United States)

    Yoo, Sun Hong; Jang, Jeong Won; Kwon, Jung Hyun; Jung, Seung Min; Jang, Bohyun; Choi, Jong Young

    2016-12-01

    Hepatic damage during transarterial chemoembolization (TACE) is a critical complication in patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). Apart from its role in preventing HBV reactivation, there is some evidence for the benefits of preemptive antiviral therapy in TACE. This study evaluated the effect of preemptive antiviral therapy on acute hepatic deterioration following TACE. This retrospective observational study included a prospectively collected cohort of 108 patients with HBV-related HCC who underwent TACE between January 2007 and January 2013. Acute hepatic deterioration following TACE was evaluated. Treatment-related hepatic decompensation was defined as newly developed encephalopathy, ascites, variceal bleeding, elevation of the bilirubin level, prolongation of prothrombin time, or elevation of the Child-Pugh score by ≥2 within 2 weeks following TACE. Univariate and multivariate analyses were conducted to identify factors influencing treatment-related decompensation. Preemptive antiviral therapy involves directing prophylaxis only toward high-risk chronic hepatitis B patients in an attempt to prevent the progression of liver disease. We regarded at least 6 months as a significant duration of preemptive antiviral treatment before diagnosis of HCC. Of the 108 patients, 30 (27.8%) patients received preemptive antiviral therapy. Treatment-related decompensation was observed in 25 (23.1%) patients during the follow-up period. Treatment-related decompensation following TACE was observed more frequently in the nonpreemptive group than in the preemptive group (29.5% vs. 6.7%, P=0.008). In the multivariate analysis, higher serum total bilirubin (Hazard ratio [HR] =3.425, P=0.013), hypoalbuminemia (HR=3.990, P=0.015), and absence of antiviral therapy (HR=7.597, P=0.006) were significantly associated with treatment-related hepatic decompensation. Our findings suggest that preemptive antiviral therapy significantly reduces the risk of

  16. Multiple latent viruses reactivate in astronauts during Space Shuttle missions.

    Science.gov (United States)

    Mehta, S K; Laudenslager, M L; Stowe, R P; Crucian, B E; Sams, C F; Pierson, D L

    2014-10-01

    Latent virus reactivation and diurnal salivary cortisol and dehydroepiandrosterone were measured prospectively in 17 astronauts (16 male and 1 female) before, during, and after short-duration (12-16 days) Space Shuttle missions. Blood, urine, and saliva samples were collected during each of these phases. Antiviral antibodies and viral load (DNA) were measured for Epstein-Barr virus (EBV), varicella-zoster virus (VZV), and cytomegalovirus (CMV). Three astronauts did not shed any virus in any of their samples collected before, during, or after flight. EBV was shed in the saliva in all of the remaining 14 astronauts during all 3 phases of flight. Seven of the 14 EBV-shedding subjects also shed VZV during and after the flight in their saliva samples, and 8 of 14 EBV-shedders also shed CMV in their urine samples before, during, and after flight. In 6 of 14 crewmembers, all 3 target viruses were shed during one or more flight phases. Both EBV and VZV DNA copies were elevated during the flight phase relative to preflight or post-flight levels. EBV DNA in peripheral blood was increased preflight relative to post-flight. Eighteen healthy controls were also included in the study. Approximately 2-5% of controls shed EBV while none shed VZV or CMV. Salivary cortisol measured preflight and during flight were elevated relative to post-flight. In contrast DHEA decreased during the flight phase relative to both preflight and post-flight. As a consequence, the molar ratio of the area under the diurnal curve of cortisol to DHEA with respect to ground (AUCg) increased significantly during flight. This ratio was unrelated to viral shedding. In summary, three herpes viruses can reactivate individually or in combination during spaceflight.

  17. Clinical Implications of Antiviral Resistance in Influenza

    Directory of Open Access Journals (Sweden)

    Timothy C. M. Li

    2015-09-01

    Full Text Available Influenza is a major cause of severe respiratory infections leading to excessive hospitalizations and deaths globally; annual epidemics, pandemics, and sporadic/endemic avian virus infections occur as a result of rapid, continuous evolution of influenza viruses. Emergence of antiviral resistance is of great clinical and public health concern. Currently available antiviral treatments include four neuraminidase inhibitors (oseltamivir, zanamivir, peramivir, laninamivir, M2-inibitors (amantadine, rimantadine, and a polymerase inhibitor (favipiravir. In this review, we focus on resistance issues related to the use of neuraminidase inhibitors (NAIs. Data on primary resistance, as well as secondary resistance related to NAI exposure will be presented. Their clinical implications, detection, and novel therapeutic options undergoing clinical trials are discussed.

  18. Clinical Implications of Antiviral Resistance in Influenza.

    Science.gov (United States)

    Li, Timothy C M; Chan, Martin C W; Lee, Nelson

    2015-09-14

    Influenza is a major cause of severe respiratory infections leading to excessive hospitalizations and deaths globally; annual epidemics, pandemics, and sporadic/endemic avian virus infections occur as a result of rapid, continuous evolution of influenza viruses. Emergence of antiviral resistance is of great clinical and public health concern. Currently available antiviral treatments include four neuraminidase inhibitors (oseltamivir, zanamivir, peramivir, laninamivir), M2-inibitors (amantadine, rimantadine), and a polymerase inhibitor (favipiravir). In this review, we focus on resistance issues related to the use of neuraminidase inhibitors (NAIs). Data on primary resistance, as well as secondary resistance related to NAI exposure will be presented. Their clinical implications, detection, and novel therapeutic options undergoing clinical trials are discussed.

  19. Exploiting Genetic Interference for Antiviral Therapy.

    Science.gov (United States)

    Tanner, Elizabeth J; Kirkegaard, Karla A; Weinberger, Leor S

    2016-05-01

    Rapidly evolving viruses are a major threat to human health. Such viruses are often highly pathogenic (e.g., influenza virus, HIV, Ebola virus) and routinely circumvent therapeutic intervention through mutational escape. Error-prone genome replication generates heterogeneous viral populations that rapidly adapt to new selection pressures, leading to resistance that emerges with treatment. However, population heterogeneity bears a cost: when multiple viral variants replicate within a cell, they can potentially interfere with each other, lowering viral fitness. This genetic interference can be exploited for antiviral strategies, either by taking advantage of a virus's inherent genetic diversity or through generating de novo interference by engineering a competing genome. Here, we discuss two such antiviral strategies, dominant drug targeting and therapeutic interfering particles. Both strategies harness the power of genetic interference to surmount two particularly vexing obstacles-the evolution of drug resistance and targeting therapy to high-risk populations-both of which impede treatment in resource-poor settings.

  20. An antiviral furanoquinone from Paulownia tomentosa Steud.

    Science.gov (United States)

    Kang, K H; Huh, H; Kim, B K; Lee, C K

    1999-11-01

    A methanol extract of the stem bark of Paulownia tomentosa showed antiviral activity against poliovirus types 1 and 3. Sequential liquid-liquid extraction with n-hexane, chloroform and water, and a silicagel column chromatography resulted in the purification of a compound. The compound was identified as methyl-5-hydroxy-dinaphthol[1,2-2',3']furan-7,12-dione-6-carbox yla te on the basis of spectroscopic data. The component caused a significant reduction of viral cytopathic effect when it was subjected to a standard antiviral assay by using HeLa cells. The EC(50) of the compound against poliovirus type 1 strain Brunhilde, and type 3 strain Leon were 0.3 microg/mL and 0.6 microg/mL, respectively.

  1. Antiviral Strategies for Pandemic and Seasonal Influenza

    Directory of Open Access Journals (Sweden)

    Fang Fang

    2010-08-01

    Full Text Available While vaccines are the primary public health response to seasonal and pandemic flu, short of a universal vaccine there are inherent limitations to this approach. Antiviral drugs provide valuable alternative options for treatment and prophylaxis of influenza. Here, we will review drugs and drug candidates against influenza with an emphasis on the recent progress of a host-targeting entry-blocker drug candidate, DAS181, a sialidase fusion protein.

  2. Antiviral Lead Compounds from Marine Sponges

    Directory of Open Access Journals (Sweden)

    Kenneth P. Minneman

    2010-10-01

    Full Text Available Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Several of them have successfully been approved as antiviral agents for clinical use or have been advanced to the late stages of clinical trials. Most of these drugs are used for the treatment of human immunodeficiency virus (HIV and herpes simplex virus (HSV. The most important antiviral lead of marine origin reported thus far is nucleoside Ara-A (vidarabine isolated from sponge Tethya crypta. It inhibits viral DNA polymerase and DNA synthesis of herpes, vaccinica and varicella zoster viruses. However due to the discovery of new types of viruses and emergence of drug resistant strains, it is necessary to develop new antiviral lead compounds continuously. Several sponge derived antiviral lead compounds which are hopedto be developed as future drugs are discussed in this review. Supply problems are usually the major bottleneck to the development of these compounds as drugs during clinical trials. However advances in the field of metagenomics and high throughput microbial cultivation has raised the possibility that these techniques could lead to the cost-effective large scale production of such compounds. Perspectives on biotechnological methods with respect to marine drug development are also discussed.

  3. Avian Interferons and Their Antiviral Effectors

    OpenAIRE

    Santhakumar, Diwakar; Rubbenstroth, Dennis; Martinez-Sobrido, Luis; Munir, Muhammad

    2017-01-01

    Interferon (IFN) responses, mediated by a myriad of IFN-stimulated genes (ISGs), are the most profound innate immune responses against viruses. Cumulatively, these IFN effectors establish a multilayered antiviral state to safeguard the host against invading viral pathogens. Considerable genetic and functional characterizations of mammalian IFNs and their effectors have been made, and our understanding on the avian IFNs has started to expand. Similar to mammalian counterparts, three types of I...

  4. Antiviral lead compounds from marine sponges

    KAUST Repository

    Sagar, Sunil

    2010-10-11

    Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Several of them have successfully been approved as antiviral agents for clinical use or have been advanced to the late stages of clinical trials. Most of these drugs are used for the treatment of human immunodeficiency virus (HIV) and herpes simplex virus (HSV). The most important antiviral lead of marine origin reported thus far is nucleoside Ara-A (vidarabine) isolated from sponge Tethya crypta. It inhibits viral DNA polymerase and DNA synthesis of herpes, vaccinica and varicella zoster viruses. However due to the discovery of new types of viruses and emergence of drug resistant strains, it is necessary to develop new antiviral lead compounds continuously. Several sponge derived antiviral lead compounds which are hopedto be developed as future drugs are discussed in this review. Supply problems are usually the major bottleneck to the development of these compounds as drugs during clinical trials. However advances in the field of metagenomics and high throughput microbial cultivation has raised the possibility that these techniques could lead to the cost-effective large scale production of such compounds. Perspectives on biotechnological methods with respect to marine drug development are also discussed. 2010 by the authors; licensee MDPI.

  5. Cross-reactivity of tree shrew sera with various secondary antibodies:extensive application to tree shrew models of diseases%树鼩血清与多种二抗的交叉反应:可在树鼩疾病动物模型中广泛应用

    Institute of Scientific and Technical Information of China (English)

    阮光萍; 姚翔; 刘菊芬; 王金祥; 何洁; 杨建勇; 潘兴华

    2015-01-01

      结果与结论:Western 结果表明树鼩的血清与抗兔、抗羊、抗人、抗小鼠、抗大鼠的二抗均不发生反应,与抗猴的二抗有交叉反应。ELISA 的结果也表明树鼩的血清与抗猴的二抗有交叉反应,而与其他二抗没有交叉反应。结果说明通常卖的二抗不能用于树鼩IgG的免疫检测,只有抗猴的二抗与树鼩的血清发生交叉反应,必需制备抗树鼩IgG的单克隆和多克隆抗体,在没有现成抗体可用时,可采用抗猴的二抗替代检测,能在树鼩疾病动物模型的研究中得到广泛应用。%BACKGROUND:Tree shrew is a representative between insectivore and primates, has a high degree of evolution, is more inexpensive primates, has high use of medical biology, and has been attached by scholars. OBJECTIVE:To detect whether the commonly used secondary antibodies have immune response with tree shrew serum. METHODS:Western blot assay and enzyme linked immunosorbent assay were utilized to detect whether the tree shrew serum had cross-reacts with anti-rabbit, anti-goat, anti-human, anti-mouse, anti-rat, and anti-monkey secondary antibodies. RESULTS AND CONCLUSION:Western blot assay results indicated that tree shrew serums did not react with anti-rabbit, anti-goat, anti-human, anti-mouse, and anti-rat secondary antibodies and had cross reaction with anti-monkey secondary antibody. Enzyme linked immunosorbent assay results also indicated that tree shrew serums were cross-reactive with anti-monkey secondary antibody, but did not have cross-reactivity with the other secondary antibodies. Above data confirmed that the usual y soled secondary antibody cannot be used to immunoassay with tree shrews IgG. Only anti-monkey secondary antibody has cross-react with tree shrew serum. It is necessary to prepare anti-tree shrew IgG monoclonal and polyclonal antibodies. When no antibody is readily available at present, anti-monkey secondary antibody can be used to substitute

  6. Cycluridine: A novel antiviral effective against flaviviruses.

    Science.gov (United States)

    Galabov, Angel S; Mukova, Lucia; Abashev, Yuriy P; Wassilewa, Lilia; Tzvetkov, Petko; Minkov, Vassil; Barinskiy, Igor F; Rice, Charles M; Ouzounov, Sergey; Sidzhakova, Dorotea

    2017-08-01

    This review describes the contemporary state of research for antivirals effective against flaviviruses, especially focusing on inhibitors of the pestivirus causative agent of bovine viral diarrhoea virus. We highlight cycluridine, an originally synthesized Mannich's base [a tetrahydro-2(1H)-pyrimidinones derivative], as a highly effective antiviral possessing a strong inhibitory effect on bovine viral diarrhoea virus replication. Cycluridine was active against replication of a wide variety of bovine viral diarrhoea virus strains in cell cultures. The drug-sensitive period in the bovine viral diarrhoea virus replication cycle included the latent period and the exponential phase; a 90-min delay in the peak of viral RNA synthesis was observed. Cycluridine administered orally manifested a pronounced protective effect in calves with natural mucosal disease/viral diarrhoea and calves experimentally infected with bovine viral diarrhoea virus. Its magnitude of activity and selectivity places cycluridine in the lead among all known substances with anti- bovine viral diarrhoea virus activity. Additionally, cycluridine applied subcutaneously showed anti-tick-born encephalitis virus activity, manifesting a marked protective effect in mice infected with tick-born encephalitis virus. Cycluridine could be a prospective antiviral in veterinary and medical practice for the treatment of bovine viral diarrhoea virus and other flavivirus infections.

  7. Antiviral biflavonoids from Radix Wikstroemiae (Liaogewanggen

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    Ye Wencai

    2010-06-01

    Full Text Available Abstract Background Radix Wikstroemiae is a common Chinese herbal medicine. The ethyl acetate fraction of the ethanolic extract of W. indica possesses potent in vitro antiviral activity against respiratory syncytial virus (RSV. This study aims to identify the antiviral components of the active fraction. Methods The active fraction of the Radix Wikstroemiae extract was isolated with chromatographic methods such as silica gel, Sephadex LH-20 and semi-preparative high performance liquid chromatography (HPLC columns. The structures of the isolated compounds were determined based on spectroscopic analyses. The in vitro antiviral activity of the compounds against RSV was tested with the cytopathic effect (CPE reduction assay and the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT method. Results Four biflavonoids, namely neochamaejasmin B, genkwanol B, genkwanol C and stelleranol, were isolated and characterized. Genkwanol B, genkwanol C and stelleranol, which are stereo isomers of spirobiflavonoids, showed potent anti-RSV activity whereas neochamaejasmin B did not. Conclusion Neochamaejasmin B, genkwanol B, genkwanol C and stelleranol were isolated from Radix Wikstroemiae and the complete absolute configurations of five chiral carbons in stelleranol were substantiated for the first time. Furthermore, the anti-RSV activity of genkwanol B, genkwanol C and stelleranol was reported for the first time.

  8. CRM1 Inhibitors for Antiviral Therapy

    Directory of Open Access Journals (Sweden)

    Cynthia Mathew

    2017-06-01

    Full Text Available Infectious diseases are a major global concern and despite major advancements in medical research, still cause significant morbidity and mortality. Progress in antiviral therapy is particularly hindered by appearance of mutants capable of overcoming the effects of drugs targeting viral components. Alternatively, development of drugs targeting host proteins essential for completion of viral lifecycle holds potential as a viable strategy for antiviral therapy. Nucleocytoplasmic trafficking pathways in particular are involved in several pathological conditions including cancer and viral infections, where hijacking or alteration of function of key transporter proteins, such as Chromosome Region Maintenance1 (CRM1 is observed. Overexpression of CRM1-mediated nuclear export is evident in several solid and hematological malignancies. Interestingly, CRM1-mediated nuclear export of viral components is crucial in various stages of the viral lifecycle and assembly. This review summarizes the role of CRM1 in cancer and selected viruses. Leptomycin B (LMB is the prototypical inhibitor of CRM1 potent against various cancer cell lines overexpressing CRM1 and in limiting viral infections at nanomolar concentrations in vitro. However, the irreversible shutdown of nuclear export results in high cytotoxicity and limited efficacy in vivo. This has prompted search for synthetic and natural CRM1 inhibitors that can potentially be developed as broadly active antivirals, some of which are summarized in this review.

  9. Recombinant Protein Truncation Strategy for Inducing Bactericidal Antibodies to the Macrophage Infectivity Potentiator Protein of Neisseria meningitidis and Circumventing Potential Cross-Reactivity with Human FK506-Binding Proteins

    OpenAIRE

    Bielecka, Magdalena K.; Devos, Nathalie; Gilbert, Mélanie; Hung, Miao-Chiu; Weynants, Vincent; Heckels, John E.; Christodoulides, Myron

    2014-01-01

    A recombinant macrophage infectivity potentiator (rMIP) protein of Neisseria meningitidis induces significant serum bactericidal antibody production in mice and is a candidate meningococcal vaccine antigen. However, bioinformatics analysis of MIP showed some amino acid sequence similarity to human FK506-binding proteins (FKBPs) in residues 166 to 252 located in the globular domain of the protein. To circumvent the potential concern over generating antibodies that could recognize human protein...

  10. Engineering broadly neutralizing antibodies for HIV prevention and therapy.

    Science.gov (United States)

    Hua, Casey K; Ackerman, Margaret E

    2016-08-01

    A combination of advances spanning from isolation to delivery of potent HIV-specific antibodies has begun to revolutionize understandings of antibody-mediated antiviral activity. As a result, the set of broadly neutralizing and highly protective antibodies has grown in number, diversity, potency, and breadth of viral recognition and neutralization. These antibodies are now being further enhanced by rational engineering of their anti-HIV activities and coupled to cutting edge gene delivery and strategies to optimize their pharmacokinetics and biodistribution. As a result, the prospects for clinical use of HIV-specific antibodies to treat, clear, and prevent HIV infection are gaining momentum. Here we discuss the diverse methods whereby antibodies are being optimized for neutralization potency and breadth, biodistribution, pharmacokinetics, and effector function with the aim of revolutionizing HIV treatment and prevention options.

  11. Self-interest versus group-interest in antiviral control.

    Directory of Open Access Journals (Sweden)

    Michiel van Boven

    Full Text Available Antiviral agents have been hailed to hold considerable promise for the treatment and prevention of emerging viral diseases like H5N1 avian influenza and SARS. However, antiviral drugs are not completely harmless, and the conditions under which individuals are willing to participate in a large-scale antiviral drug treatment program are as yet unknown. We provide population dynamical and game theoretical analyses of large-scale prophylactic antiviral treatment programs. Throughout we compare the antiviral control strategy that is optimal from the public health perspective with the control strategy that would evolve if individuals make their own, rational decisions. To this end we investigate the conditions under which a large-scale antiviral control program can prevent an epidemic, and we analyze at what point in an unfolding epidemic the risk of infection starts to outweigh the cost of antiviral treatment. This enables investigation of how the optimal control strategy is moulded by the efficacy of antiviral drugs, the risk of mortality by antiviral prophylaxis, and the transmissibility of the pathogen. Our analyses show that there can be a strong incentive for an individual to take less antiviral drugs than is optimal from the public health perspective. In particular, when public health asks for early and aggressive control to prevent or curb an emerging pathogen, for the individual antiviral drug treatment is attractive only when the risk of infection has become non-negligible. It is even possible that from a public health perspective a situation in which everybody takes antiviral drugs is optimal, while the process of individual choice leads to a situation where nobody is willing to take antiviral drugs.

  12. Reactivation of intestinal CMV in a renal transplant patient after 10 years from the transplant

    Directory of Open Access Journals (Sweden)

    Maria Landi

    2013-04-01

    Full Text Available Introduction.We analyzed the clinical case of a 51 years old man, kidney transplanted on December 2002. On April 2011, he had acute rectal bleeding, renal chronic rejection (creatinine 2.9 mg/dl, Hgb 8.7 g/dl, positive anti-CMV antibodies (IgG. A colonoscopy showed diverticulosis of the rectum associated with deepithelialisation. The patient was treated with maintenance immunosuppressive post-transplant therapy. On June 2011, the colonoscopy showed a stenosing lesion of the sigmoid colon, and blood sampling and intestinal biopsy were performed to search Cytomegalovirus (CMV DNA by PCR. Methods. The presence of CMV-DNA was sought by automatic extractor QIACUBE, using QIAamp DNA BLOOD Mini Kit (Qiagen for whole blood and QIAamp DNA Mini Kit (Qiagen for biopsy.The extracted DNA was then amplified by Real Time PCR using Q-CMV RealTime Complete Kit (Nanogen, on instrument Applied Biosystems 7300. Results. At disease onset the viral load in whole blood was 208000 Geq/ml, and biopsy was positive. Antiviral therapy with Ganciclovir led to the negativity of the viral load and remission of symptoms. Conclusions. The clinical case described presented a reactivation of CMV infection in the intestine after more than 10 years from kidney transplantation, while the highest incidence of CMV reactivation usually occurs during the first year. In our opinion, the reactivation can be traced to long-term immunosuppressive therapy (maintenance posttransplant therapy in combination with a state of inflammation of the intestinal mucosa. In fact, patients with IBD treated with steroid drugs, in particular the group of refractory to therapy and thus have a recovery of the inflammatory process, are exposed to reactivation of CMV with intestinal localization.

  13. [Latest Treatment of Viral Hepatitis--Overcoming Hepatitis C and Reactivation of Hepatitis B].

    Science.gov (United States)

    Tanaka, Yasuhito

    2016-02-01

    Hepatitis B virus (HBV) and hepatitis C virus (HCV), discovered as causative viruses of post-transfusion hepatitis, become persistent infections, leading to chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). For HCV, recent IFN-free direct-acting antiviral (DAA) therapies have increased sustained virological response (SVR) rates and reduced adverse events. IFN-based therapies, still the standard of care in Asian countries, are influenced by IL28B genetic variants and the liver fibrosis stage, but the DAA combinations obscure the influence of these factors. These new therapies can eradicate HCV and prevent HCC development. On the other hand, it is difficult to eradicate HBV completely. Although HBV infection can be prevented by vaccination, reactivation of HBV following anti-cancer chemotherapy and immunosuppressive therapy is a well-known complication. HBV reactivation has been reported to be associated with anti-CD20 monoclonal antibody rituximab-containing chemotherapy and TNF-α inhibitor-containing immunosuppressive therapy in HBV-resolved patients. Our prospective observational study revealed that monthly monitoring of HBV DNA was useful for preventing HBV reactivation-related hepatitis among B-cell non-Hodgkin lymphoma patients with resolved HBV infection following rituximab-steroid-chemo, suggesting that preemptive therapy guided by serial HBV DNA monitoring should be recommended. Recently, highly sensitive HBsAg detection by Lumipulse HBsAg-HQ may be useful for several clinical applications. The sensitivity of this assay (5 mIU/mL) was approximately 10-fold higher than Abbott ARCHITECT, but still lower than HBV-DNA assays. The convenient HBsAg-HQ may be useful for detecting occult HBV infection and HBV reactivation in relatively low-risk groups except for those receiving rituximab-steroid-chemo. [

  14. Do HIV-specific CTL continue to have an antiviral function during antiretroviral therapy? If not, why not, and what can be done about it?

    OpenAIRE

    Dorian eMcIlroy

    2013-01-01

    Pharmacological re-activation of HIV expression from latent proviruses coupled with fully suppressive anti-retroviral therapy (ART) has been suggested as a strategy to eradicate HIV infection. In order for this strategy to be effective, latently infected cells must be killed either by the cytopathic effect of reactivated HIV gene expression, or by HIV-specific CTL. However, a review of current data reveals little evidence that CTL retain an anti-viral effector capacity in patients on fully su...

  15. Ribonuclease, deoxyribonuclease, and antiviral activity of Escherichia coli-expressed Bougainvillea xbuttiana antiviral protein 1.

    Science.gov (United States)

    Choudhary, N L; Yadav, O P; Lodha, M L

    2008-03-01

    A full-length cDNA encoding ribosome-inactivating/antiviral protein from the leaves of Bougainvillea xbuttiana was recently isolated. The coding region of cDNA was cloned and expressed in Escherichia coli, and the protein product was designated as BBAP1 (Bougainvillea xbuttiana antiviral protein 1). BBAP1 showed ribonuclease activity against Torula yeast RNA. It also exhibited depurination activity against supercoiled pBlueScript SK+ plasmid DNA in a concentration dependent manner, and was found to convert nicked circular DNA into linear form only at higher concentration. On bioassay, BBAP1 exhibited antiviral activity against sunnhemp rosette virus infecting Cyamopsis tetragonoloba leaves in which 95% inhibition of local lesion formation was observed.

  16. Chemokine receptors as new molecular targets for antiviral therapy.

    Science.gov (United States)

    Santoro, F; Vassena, L; Lusso, P

    2004-04-01

    Extraordinary advancements have been made over the past decade in our understanding of the molecular mechanism of human immunodeficiency virus (HIV) entry into cells. The external HIV envelope glycoprotein, gp120, sequentially interacts with two cellular receptor molecules, the CD4 glycoprotein and a chemokine receptor, such as CCR5 or CXCR4, leading to the activation of the fusogenic domain of the transmembrane viral glycoprotein, gp41, which changes its conformation to create a hairpin structure that eventually triggers fusion between the viral and cellular membranes. Each of these discrete steps in the viral entry process represents a potential target for new antiviral agents. Current efforts to develop safe and effective HlV entry inhibitors are focused on naturally occurring proteins (e.g., chemokines, antibodies), engineered or modified derivatives of natural proteins (e.g., multimerized soluble CD4, gp41--or chemokine--derived synthetic peptides), as well as small synthetic compounds obtained either by high-throughput screening of large compound libraries or by structure-guided rational design. The recent introduction in therapy of the first fusion inhibitor, the gp41-derived synthetic peptide T20, heralds a new era in the treatment of AIDS, which will hopefully lead to more effective multi-drug regimens with reduced adverse effects for the patients.

  17. Hepatitis C virus cell-cell transmission and resistance to direct-acting antiviral agents.

    Directory of Open Access Journals (Sweden)

    Fei Xiao

    2014-05-01

    Full Text Available Hepatitis C virus (HCV is transmitted between hepatocytes via classical cell entry but also uses direct cell-cell transfer to infect neighboring hepatocytes. Viral cell-cell transmission has been shown to play an important role in viral persistence allowing evasion from neutralizing antibodies. In contrast, the role of HCV cell-cell transmission for antiviral resistance is unknown. Aiming to address this question we investigated the phenotype of HCV strains exhibiting resistance to direct-acting antivirals (DAAs in state-of-the-art model systems for cell-cell transmission and spread. Using HCV genotype 2 as a model virus, we show that cell-cell transmission is the main route of viral spread of DAA-resistant HCV. Cell-cell transmission of DAA-resistant viruses results in viral persistence and thus hampers viral eradication. We also show that blocking cell-cell transmission using host-targeting entry inhibitors (HTEIs was highly effective in inhibiting viral dissemination of resistant genotype 2 viruses. Combining HTEIs with DAAs prevented antiviral resistance and led to rapid elimination of the virus in cell culture model. In conclusion, our work provides evidence that cell-cell transmission plays an important role in dissemination and maintenance of resistant variants in cell culture models. Blocking virus cell-cell transmission prevents emergence of drug resistance in persistent viral infection including resistance to HCV DAAs.

  18. Antiviral activity of Thiosemicarbazones derived from α-amino acids against Dengue virus.

    Science.gov (United States)

    Padmanabhan, Padmapriya; Khaleefathullah, Sheriff; Kaveri, Krishansamy; Palani, Gunasekaran; Ramanathan, Giriprasath; Thennarasu, Sathiah; Tirichurapalli Sivagnanam, Uma

    2017-03-01

    The endemicity and seasonal outbreaks of Dengue disease in most tropical and subtropical countries underscores an urgent need to develop effective prevention and control measures. Development of a Dengue vaccine, which is complicated by the Antibody Dependent Enhancement effect (ADE), a viral inhibitor, seems prudent as it would inhibit the spread of the virus. In vitro methods such as MTT assay and plaque formation unit reduction assays were employed for screening the viral inhibitory property of α-amino acid based Thiosemicarbazides. The results elicits that at concentrations not exceeding the maximum non cytotoxic concentration (MNCC), these compounds completely prevented Dengue virus infection in vero cells as indicated by the absence of cytopathic effects in a dose-dependent manner. The high potency of Bz-Trp-TSC against all four types of Dengue virus infection elevates Thiosemicarbazide as a lead antiviral agent for Dengue disease. Screening small molecules for antiviral activity against the most rapidly spreading mosquito-borne viral disease is being explored by several research groups. Our findings would help to augment the efforts to identify the lead compounds for antiviral therapy to combat the Dengue disease. J. Med. Virol. 89:546-552, 2017. © 2016 Wiley Periodicals, Inc.

  19. Reactive Hypoglycemia

    Science.gov (United States)

    ... from low blood sugar (hypoglycemia) that occurs while fasting. Signs and symptoms of reactive hypoglycemia may include ... and very important. It's also important to include physical activity in your daily routine. Your doctor can help ...

  20. Reactive Arthritis

    Directory of Open Access Journals (Sweden)

    Eren Erken

    2013-06-01

    Full Text Available Reactive arthritis is an acute, sterile, non-suppurative and inflammatory arthropaty which has occured as a result of an infectious processes, mostly after gastrointestinal and genitourinary tract infections. Reiter syndrome is a frequent type of reactive arthritis. Both reactive arthritis and Reiter syndrome belong to the group of seronegative spondyloarthropathies, associated with HLA-B27 positivity and characterized by ongoing inflammation after an infectious episode. The classical triad of Reiter syndrome is defined as arthritis, conjuctivitis and urethritis and is seen only in one third of patients with Reiter syndrome. Recently, seronegative asymmetric arthritis and typical extraarticular involvement are thought to be adequate for the diagnosis. However, there is no established criteria for the diagnosis of reactive arthritis and the number of randomized and controlled studies about the therapy is not enough. [Archives Medical Review Journal 2013; 22(3.000: 283-299

  1. New ribosome-inactivating proteins with polynucleotide:adenosine glycosidase and antiviral activities from Basella rubra L. and bougainvillea spectabilis Willd.

    Science.gov (United States)

    Bolognesi, A; Polito, L; Olivieri, F; Valbonesi, P; Barbieri, L; Battelli, M G; Carusi, M V; Benvenuto, E; Del Vecchio Blanco, F; Di Maro, A; Parente, A; Di Loreto, M; Stirpe, F

    1997-12-01

    New single-chain (type 1) ribosome-inactivating proteins (RIPs) were isolated from the seeds of Basella rubra L. (two proteins) and from the leaves of Bougainvillea spectabilis Willd. (one protein). These RIPs inhibit protein synthesis both in a cell-free system, with an IC50 (concentration causing 50% inhibition) in the 10(-10) M range, and by various cell lines, with IC50S in the 10(-8)-10(-6) M range. All three RIPs released adenine not only from rat liver ribosomes but also from Escherichia coli rRNA, polyadenylic acid, herring sperm DNA, and artichoke mottled crinkle virus (AMCV) genomic RNA, thus being polynucleotide:adenosine glycosidases. The proteins from Basella rubra had toxicity to mice similar to that of most type 1 RIPs (Barbieri et al., 1993, Biochim Biophys Acta 1154: 237-282) with an LD50 (concentration that is 50% lethal) Bougainvillea spectabilis had an LD50 > 32 mg.kg-1. The N-terminal sequence of the two RIPs from Basella rubra had 80-93% identity, whereas it differed from the sequence of the RIP from Bougainvillea spectabilis. When tested with antibodies against various RIPs, the RIPs from Basella gave some cross-reactivity with sera against dianthin 32, and weak cross-reactivity with momordin I and momorcochin-S, whilst the RIP from Bougainvillea did not cross-react with any antiserum tested. An RIP from Basella rubra and one from Bougainvillea spectabilis were tested for antiviral activity, and both inhibited infection of Nicotiana benthamiana by AMCV.

  2. A study of the human immune response to Lolium perenne (rye) pollen and its components, Lol p I and Lol p II (rye I and rye II). I. Prevalence of reactivity to the allergens and correlations among skin test, IgE antibody, and IgG antibody data.

    Science.gov (United States)

    Freidhoff, L R; Ehrlich-Kautzky, E; Grant, J H; Meyers, D A; Marsh, D G

    1986-12-01

    In a stratified random sample of 320 white adults, the prevalence of puncture skin test positivity (ST +) to Lolium perenne (rye grass)-pollen extract (LPE) was 16%. Fifteen percent of all subjects (or 84% of subjects classified LPE IgE antibody positive [Ab +]) was classified IgE Ab + to highly purified Lol p I (Rye I), and 4% of all subjects (or 26% of subjects classified LPE IgE Ab +) was classified IgE Ab + to highly purified Lol p II (Rye II). These data and similar results obtained in an allergy-enriched group of 361 subjects are consistent with previous studies that Lol I is a major allergen and Lol II is a minor allergen of LPE. Whether we studied LPE, Lol I, or Lol II, responder subjects were younger than nonresponder subjects and more male than female subjects were responders. We then investigated the quantitative interrelationships among ST, IgE, and IgG Ab responsiveness to LPE, Lol I, and Lol II in the allergy-enriched group. For each allergen, log-log correlations were strong and significant for ST versus IgE Ab and for IgE Ab versus IgG Ab. All subjects IgE Ab + to Lol I or Lol II were IgG Ab + to that allergen, supporting other evidence for a commonality in the genetic control influencing the production of IgE and IgG Abs to a given allergen. Log-log correlations among ST end points, IgE Ab levels, or IgG Ab levels were strong for LPE versus either Lol I or Lol II but weak between Lol I and Lol II, consistent with the reported lack of cross-reactivity between Lol I and Lol II. Despite these findings, almost all Lol II + subjects were Lol I + by ST (98%), IgE Ab (91%), and IgG Ab (83%), suggesting that the Ia-restricted immune recognition of both these molecules is at least in part under a common genetic control.

  3. HIV/HCV Antiviral Drug Interactions in the Era of Direct-acting Antivirals

    Science.gov (United States)

    Rice, Donald P.; Faragon, John J.; Banks, Sarah; Chirch, Lisa M.

    2016-01-01

    Abstract Therapy for human immunodeficiency virus (HIV) and chronic hepatitis C has evolved over the past decade, resulting in better control of infection and clinical outcomes; however, drug-drug interactions remain a significant hazard. Joint recommendations from the American Association for the Study of Liver Diseases and the Infectious Diseases Society of America regarding drug-drug interactions between HIV antiretroviral agents and direct-acting antiviral agents for treatment of hepatitis C virus (HCV) infection are reviewed here. This review is oriented to facilitate appropriate selection of an antiviral therapy regimen for HCV infection based on the choice of antiretroviral therapy being administered and, if necessary, switching antiretroviral regimens. PMID:27777891

  4. A study on associations between antiprothrombin antibodies, antiplasminogen antibodies and thrombosis

    NARCIS (Netherlands)

    Simmelink, MJA; De Groot, PG; Derksen, RHWM

    2003-01-01

    Anti-prothrombin antibodies area frequent cause of lupus anticoagulant (LAC), a thrombotic risk factor. Prothrombin shares structural homology with plasminogen, a kringle protein with an important role in fibrinolysis. Cross-reactivity between antiprothrombin antibodies and plasminogen has been desc

  5. Structural, topological and vibrational properties of an isothiazole derivatives series with antiviral activities

    Science.gov (United States)

    Romani, Davide; Márquez, María J.; Márquez, María B.; Brandán, Silvia A.

    2015-11-01

    In this work, the structural, topological and vibrational properties of an isothiazole derivatives series with antiviral activities in gas and aqueous solution phases were studied by using DFT calculations. The self consistent reaction field (SCRF) method was combined with the polarized continuum (PCM) model in order to study the solvent effects and to predict their reactivities and behaviours in both media. Thus, the 3-mercapto-5-phenyl-4-isothiazolecarbonitrile (I), 3-methylthio-5-phenyl-4-isothiazolecarbonitrile (II), 3-Ethylthio-5-phenyl-4-isothiazolecarbonitrile (III), S-[3-(4-cyano-5-phenyl)isothiazolyl] ethyl thiocarbonate (IV), 5-Phenyl-3-(4-cyano-5-phenylisothiazol-3-yl) disulphanyl-4-isothiazolecarbonitrile (V) and 1,2-Bis(4-cyano-5-phenylisothiazol-3-yl) sulphanyl Ethane (VI) derivatives were studied by using the hybrid B3LYP/6-31G* method. All the properties were compared and analyzed in function of the different R groups linked to the thiazole ring. This study clearly shows that the high polarity of (I) probably explains its elevated antiviral activity due to their facility to traverse biological membranes more rapidly than the other ones while in the (IV) and (V) derivatives the previous hydrolysis of both bonds increasing their antiviral properties inside the cell probably are related to their low S-R bond order values. In addition, the complete vibrational assignments and force constants are presented.

  6. Secretion of respiratory syncytial virus inhibitors and antibody in human milk throughout lactation.

    Science.gov (United States)

    Toms, G L; Gardner, P S; Pullan, C R; Scott, M; Taylor, C

    1980-01-01

    Neutralising inhibitors to respiratory syncytial (RS) virus have been demonstrated in the whey of most samples of human milk tested. Although high titres were secreted in colostra of some mothers (1/10-1/2,560; median 1/40) inhibitor levels in milk collected after the first week of lactation were uniformly low (median 1/10). High neutralising titres correlated with high colostral levels of specific antiviral IgA but, unlike neutralising activity, IgA antiviral antibody persisted in the milk of only four of 18 mothers. Similarly, antiviral IgG and IgM antibodies were not generally detected after the first post-partum week. Differences in antibody secretion among mothers did not correlate with differences in total protein or total immunoglobulin secretion, and appeared to reflect maternal immune status. In one mother a marked rise in specific antiviral IgA and IgG secretions during the second and third months of lactation suggested a response to virus infection. The relevance of maternal immunity and colostral and milk antiviral antibody to protection of breast-fed babies from RS-virus bronchiolitis is discussed.

  7. Successful Management of Graft Reinfection of HCV Genotype 2 in Living Donor Liver Transplantation from a Hepatitis B Core Antibody-Positive Donor with Sofosbuvir and Ribavirin

    Science.gov (United States)

    Sasaki, Reina; Kanda, Tatsuo; Ohtsuka, Masayuki; Yasui, Shin; Haga, Yuki; Nakamura, Masato; Yokoyama, Masayuki; Wu, Shuang; Nakamoto, Shingo; Arai, Makoto; Maruyama, Hitoshi; Miyazaki, Masaru; Yokosuka, Osamu

    2016-01-01

    Direct-acting antivirals (DAAs) are relatively safe and highly effective for the eradication of hepatitis C virus (HCV) in liver transplant recipients. In this case study, we present a female with a graft reinfected with HCV genotype 2 who was treated with a combination of sofosbuvir and ribavirin after living donor liver transplantation (LDLT). Because the graft was from a hepatitis B core antibody-positive donor, passive immunization with hyperimmune hepatitis B immunoglobulin (HBIG) and entecavir were also provided to prevent hepatitis B virus (HBV) reactivation. It became clear that the combination of sofosbuvir and ribavirin promptly led to a sustained virologic response and that this combination was safe to treat graft reinfection with HCV genotype 2 after LDLT. Adverse events caused by DAAs were not observed, except for slight anemia. HBIG and entecavir were useful in the prevention of HBV reactivation. In conclusion, the present case indicated that DAA treatment for graft reinfection with HCV is safe and effective in LDLT from hepatitis B core antibody-positive donors. PMID:27721720

  8. Successful Management of Graft Reinfection of HCV Genotype 2 in Living Donor Liver Transplantation from a Hepatitis B Core Antibody-Positive Donor with Sofosbuvir and Ribavirin

    Directory of Open Access Journals (Sweden)

    Reina Sasaki

    2016-07-01

    Full Text Available Direct-acting antivirals (DAAs are relatively safe and highly effective for the eradication of hepatitis C virus (HCV in liver transplant recipients. In this case study, we present a female with a graft reinfected with HCV genotype 2 who was treated with a combination of sofosbuvir and ribavirin after living donor liver transplantation (LDLT. Because the graft was from a hepatitis B core antibody-positive donor, passive immunization with hyperimmune hepatitis B immunoglobulin (HBIG and entecavir were also provided to prevent hepatitis B virus (HBV reactivation. It became clear that the combination of sofosbuvir and ribavirin promptly led to a sustained virologic response and that this combination was safe to treat graft reinfection with HCV genotype 2 after LDLT. Adverse events caused by DAAs were not observed, except for slight anemia. HBIG and entecavir were useful in the prevention of HBV reactivation. In conclusion, the present case indicated that DAA treatment for graft reinfection with HCV is safe and effective in LDLT from hepatitis B core antibody-positive donors.

  9. Pharmacokinetic Characteristics, Pharmacodynamic Effect and In Vivo Antiviral Efficacy of Liver-Targeted Interferon Alpha

    Science.gov (United States)

    Rycroft, Daniel; Sosabowski, Jane; Coulstock, Edward; Davies, Marie; Morrey, John; Friel, Sarah; Kelly, Fiona; Hamatake, Robert; Ovečka, Milan; Prince, Rob; Goodall, Laura; Sepp, Armin; Walker, Adam

    2015-01-01

    Interferon alpha (IFNα) is used for the treatment of hepatitis B virus infection, and whilst efficacious, it is associated with multiple adverse events caused by systemic exposure to interferon. We therefore hypothesise that targeting IFN directly to the intended site of action in the liver would reduce exposure in blood and peripheral tissue and hence improve the safety and tolerability of IFNα therapy. Furthermore we investigated whether directing IFN to the reservoir of infection in the liver may improve antiviral efficacy by increasing local concentration in target organs and tissues. Our previous results show that the mIFNα2 fused to an ASGPR specific liver targeting antibody, DOM26h-196-61, results in a fusion protein which retains the activity of both fusion partners when measured in vitro. In vivo targeting of the liver by mIFNα2-DOM26h-196-61, hereafter referred to as targeted mIFNα2, was observed in microSPECT imaging studies in mice. In this study we show by pharmacokinetic analysis that antibody mediated liver-targeting results in increased uptake and exposure of targeted mIFNα2 in target tissues, and correspondingly reduced uptake and exposure in systemic circulation, clearance organs and non-target tissues. We also show that cytokine activity and antiviral activity of liver-targeted IFN is observed in vivo, but that, contrary to expectations, liver-targeting of mIFNα2 using ASGPR specific dAbs actually leads to a reduced pharmacodynamic effect in target organs and lower antiviral activity in vivo when compared to non-targeted mIFNα2-dAb fusions. PMID:25689509

  10. Pharmacokinetic characteristics, pharmacodynamic effect and in vivo antiviral efficacy of liver-targeted interferon alpha.

    Directory of Open Access Journals (Sweden)

    Daniel Rycroft

    Full Text Available Interferon alpha (IFNα is used for the treatment of hepatitis B virus infection, and whilst efficacious, it is associated with multiple adverse events caused by systemic exposure to interferon. We therefore hypothesise that targeting IFN directly to the intended site of action in the liver would reduce exposure in blood and peripheral tissue and hence improve the safety and tolerability of IFNα therapy. Furthermore we investigated whether directing IFN to the reservoir of infection in the liver may improve antiviral efficacy by increasing local concentration in target organs and tissues. Our previous results show that the mIFNα2 fused to an ASGPR specific liver targeting antibody, DOM26h-196-61, results in a fusion protein which retains the activity of both fusion partners when measured in vitro. In vivo targeting of the liver by mIFNα2-DOM26h-196-61, hereafter referred to as targeted mIFNα2, was observed in microSPECT imaging studies in mice. In this study we show by pharmacokinetic analysis that antibody mediated liver-targeting results in increased uptake and exposure of targeted mIFNα2 in target tissues, and correspondingly reduced uptake and exposure in systemic circulation, clearance organs and non-target tissues. We also show that cytokine activity and antiviral activity of liver-targeted IFN is observed in vivo, but that, contrary to expectations, liver-targeting of mIFNα2 using ASGPR specific dAbs actually leads to a reduced pharmacodynamic effect in target organs and lower antiviral activity in vivo when compared to non-targeted mIFNα2-dAb fusions.

  11. Genetic polymorphisms in host antiviral genes: associations with humoral and cellular immunity to measles vaccine.

    Science.gov (United States)

    Haralambieva, Iana H; Ovsyannikova, Inna G; Umlauf, Benjamin J; Vierkant, Robert A; Shane Pankratz, V; Jacobson, Robert M; Poland, Gregory A

    2011-11-08

    Host antiviral genes are important regulators of antiviral immunity and plausible genetic determinants of immune response heterogeneity after vaccination. We genotyped and analyzed 307 common candidate tagSNPs from 12 antiviral genes in a cohort of 745 schoolchildren immunized with two doses of measles-mumps-rubella (MMR) vaccine. Associations between SNPs/haplotypes and measles virus-specific immune outcomes were assessed using linear regression methodologies in Caucasians and African-Americans. Genetic variants within the DDX58/RIG-I gene, including a coding polymorphism (rs3205166/Val800Val), were associated as single-SNPs (p≤0.017; although these SNPs did not remain significant after correction for false discovery rate/FDR) and in haplotype-level analysis, with measles-specific antibody variations in Caucasians (haplotype allele p-value=0.021; haplotype global p-value=0.076). Four DDX58 polymorphisms, in high LD, demonstrated also associations (after correction for FDR) with variations in both measles-specific IFN-γ and IL-2 secretion in Caucasians (p≤0.001, q=0.193). Two intronic OAS1 polymorphisms, including the functional OAS1 SNP rs10774671 (p=0.003), demonstrated evidence of association with a significant allele-dose-related increase in neutralizing antibody levels in African-Americans. Genotype and haplotype-level associations demonstrated the role of ADAR genetic variants, including a non-synonymous SNP (rs2229857/Arg384Lys; p=0.01), in regulating measles virus-specific IFN-γ Elispot responses in Caucasians (haplotype global p-value=0.017). After correction for FDR, 15 single-SNP associations (11 SNPs in Caucasians and 4 SNPs in African-Americans) still remained significant at the q-valuemeasles vaccine in Caucasians and African-Americans.

  12. Research progress in the development of direct acting antiviral agents for hepatitis C and the anti-viral resistance

    Directory of Open Access Journals (Sweden)

    Song YANG

    2011-05-01

    Full Text Available Recently,directly acting antiviral agents against hepatitic C virus with different mechanisms have been developed and put into clinical trials.Especially,results of phase Ⅲ clinical trials of Boceprevir and Telaprevir have been published,and these two agents are to be approved for marketing in recent years.Also much attention has been paid on anti-viral resistance against direct acting antiviral agents.Great progresses have been made in field of direct acting antiviral agents against hepatitic C virus.Domestic studies in this area should take characteristics of virus and host of Chinese chronic hepatitis C into consideration.

  13. Critical role of an antiviral stress granule containing RIG-I and PKR in viral detection and innate immunity.

    Directory of Open Access Journals (Sweden)

    Koji Onomoto

    Full Text Available Retinoic acid inducible gene I (RIG-I-like receptors (RLRs function as cytoplasmic sensors for viral RNA to initiate antiviral responses including type I interferon (IFN production. It has been unclear how RIG-I encounters and senses viral RNA. To address this issue, we examined intracellular localization of RIG-I in response to viral infection using newly generated anti-RIG-I antibody. Immunohistochemical analysis revealed that RLRs localized in virus-induced granules containing stress granule (SG markers together with viral RNA and antiviral proteins. Because of similarity in morphology and components, we termed these aggregates antiviral stress granules (avSGs. Influenza A virus (IAV deficient in non-structural protein 1 (NS1 efficiently generated avSGs as well as IFN, however IAV encoding NS1 produced little. Inhibition of avSGs formation by removal of either the SG component or double-stranded RNA (dsRNA-dependent protein kinase (PKR resulted in diminished IFN production and concomitant enhancement of viral replication. Furthermore, we observed that transfection of dsRNA resulted in IFN production in an avSGs-dependent manner. These results strongly suggest that the avSG is the locus for non-self RNA sensing and the orchestration of multiple proteins is critical in the triggering of antiviral responses.

  14. The humoral immune response to Chlamydia trachomatis in patients with acute reactive arthritis

    DEFF Research Database (Denmark)

    Larsen, B; Birkelund, Svend; Mordhorst, CH

    1994-01-01

    Sera from 25 patients with clinical signs of reactive arthritis were analysed for antibodies against Chlamydia trachomatis by immunoblotting. Purified elementary bodies, purified Chlamydia outer membrane complexes, and purified recombinant subcomponents were used as antigens. Antibodies against C...

  15. Generation and characterization of novel stromal specific antibodies

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Rheumatoid synovial fibroblasts were used as an immunogen to produce monoclonal antibodies selected for their reactivity with stromal cell antigens. Mice were immunised with low passage whole cell preparations and the subsequent hybridomas were screened by immunohistochemistry on rheumatoid synovium and tonsil sections. The aim was to identify those antibodies that recognised antigens that were restricted to stromal cells and were not expressed on CD45 positive leucocytes. A significant number of antibodies detected antigen that identified endothelial cells. These antibodies were further characterised to determine whether the vessels identified by these antibodies were vascular or lymphatic.From five fusions clones were identified with predominant reactivity with: 1) fibroblasts and endothelial cells; or 2)broad stromal elements (fibroblast, endothelium, epithelium, follicular dendritic cells). A fibroblast-specific antibody that did not also identify vessels was not generated. Examples of each reactivity pattern are discussed.

  16. Avian Interferons and Their Antiviral Effectors.

    Science.gov (United States)

    Santhakumar, Diwakar; Rubbenstroth, Dennis; Martinez-Sobrido, Luis; Munir, Muhammad

    2017-01-01

    Interferon (IFN) responses, mediated by a myriad of IFN-stimulated genes (ISGs), are the most profound innate immune responses against viruses. Cumulatively, these IFN effectors establish a multilayered antiviral state to safeguard the host against invading viral pathogens. Considerable genetic and functional characterizations of mammalian IFNs and their effectors have been made, and our understanding on the avian IFNs has started to expand. Similar to mammalian counterparts, three types of IFNs have been genetically characterized in most avian species with available annotated genomes. Intriguingly, chickens are capable of mounting potent innate immune responses upon various stimuli in the absence of essential components of IFN pathways including retinoic acid-inducible gene I, IFN regulatory factor 3 (IRF3), and possibility IRF9. Understanding these unique properties of the chicken IFN system would propose valuable targets for the development of potential therapeutics for a broader range of viruses of both veterinary and zoonotic importance. This review outlines recent developments in the roles of avian IFNs and ISGs against viruses and highlights important areas of research toward our understanding of the antiviral functions of IFN effectors against viral infections in birds.

  17. Avian Interferons and Their Antiviral Effectors

    Science.gov (United States)

    Santhakumar, Diwakar; Rubbenstroth, Dennis; Martinez-Sobrido, Luis; Munir, Muhammad

    2017-01-01

    Interferon (IFN) responses, mediated by a myriad of IFN-stimulated genes (ISGs), are the most profound innate immune responses against viruses. Cumulatively, these IFN effectors establish a multilayered antiviral state to safeguard the host against invading viral pathogens. Considerable genetic and functional characterizations of mammalian IFNs and their effectors have been made, and our understanding on the avian IFNs has started to expand. Similar to mammalian counterparts, three types of IFNs have been genetically characterized in most avian species with available annotated genomes. Intriguingly, chickens are capable of mounting potent innate immune responses upon various stimuli in the absence of essential components of IFN pathways including retinoic acid-inducible gene I, IFN regulatory factor 3 (IRF3), and possibility IRF9. Understanding these unique properties of the chicken IFN system would propose valuable targets for the development of potential therapeutics for a broader range of viruses of both veterinary and zoonotic importance. This review outlines recent developments in the roles of avian IFNs and ISGs against viruses and highlights important areas of research toward our understanding of the antiviral functions of IFN effectors against viral infections in birds. PMID:28197148

  18. Antiviral Defenses in Plants through Genome Editing

    Science.gov (United States)

    Romay, Gustavo; Bragard, Claude

    2017-01-01

    Plant–virus interactions based-studies have contributed to increase our understanding on plant resistance mechanisms, providing new tools for crop improvement. In the last two decades, RNA interference, a post-transcriptional gene silencing approach, has been used to induce antiviral defenses in plants with the help of genetic engineering technologies. More recently, the new genome editing systems (GES) are revolutionizing the scope of tools available to confer virus resistance in plants. The most explored GES are zinc finger nucleases, transcription activator-like effector nucleases, and clustered regularly interspaced short palindromic repeats/Cas9 endonuclease. GES are engineered to target and introduce mutations, which can be deleterious, via double-strand breaks at specific DNA sequences by the error-prone non-homologous recombination end-joining pathway. Although GES have been engineered to target DNA, recent discoveries of GES targeting ssRNA molecules, including virus genomes, pave the way for further studies programming plant defense against RNA viruses. Most of plant virus species have an RNA genome and at least 784 species have positive ssRNA. Here, we provide a summary of the latest progress in plant antiviral defenses mediated by GES. In addition, we also discuss briefly the GES perspectives in light of the rebooted debate on genetic modified organisms (GMOs) and the current regulatory frame for agricultural products involving the use of such engineering technologies. PMID:28167937

  19. A humanised murine monoclonal antibody protects mice from Venezuelan equine encephalitis virus, Everglades virus and Mucambo virus when administered up to 48 h after airborne challenge

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, Lyn M., E-mail: lmobrien@dstl.gov.uk; Goodchild, Sarah A.; Phillpotts, Robert J.; Perkins, Stuart D.

    2012-05-10

    Currently there are no licensed antiviral treatments for the Alphaviruses Venezuelan equine encephalitis virus (VEEV), Everglades virus and Mucambo virus. We previously developed a humanised version of the mouse monoclonal antibody 1A3B-7 (Hu1A3B-7) which exhibited a wide range of reactivity in vitro and was able to protect mice from infection with VEEV. Continued work with the humanised antibody has now demonstrated that it has the potential to be a new human therapeutic. Hu1A3B-7 successfully protected mice from infection with multiple Alphaviruses. The effectiveness of the humanisation process was determined by assessing proliferation responses in human T-cells to peptides derived from the murine and humanised versions of the V{sub H} and V{sub L} domains. This analysis showed that the number of human T-cell epitopes within the humanised antibody had been substantially reduced, indicating that Hu1A3B-7 may have reduced immunogenicity in vivo.

  20. Latent Syphilis: Immunoglobulins Reactive in Immunofluorescence and Other Serological Tests

    Science.gov (United States)

    Julian, A. J.; Logan, L. C.; Norins, L. C.; Scotti, A. T.

    1971-01-01

    Study of sera from 69 patients with untreated or inadequately treated latent syphilis revealed that immunoglobulin (Ig)G antibodies made up the bulk of the fluorescent treponemal antibody-absorption (FTA-ABS)-test reactivity found in the sera. IgM and IgA antibodies also contributed in some cases. Venereal Disease Research Laboratory slide-test reactivity was found in both 19 and 7S serum fractions, whereas Treponema pallidum immobilization-test reactivity was found mainly in the 7S fraction. PMID:16558017

  1. Induction and suppression of the innate antiviral responses by picornaviruses

    NARCIS (Netherlands)

    Feng, Q.

    2014-01-01

    On the front line of innate antiviral immune reactions is the type I interferon (IFN-α/β) system. IFN-α/β are small signaling molecules that can be produced by virtually all nucleated cells in our body upon virus infections, and induce a so-called “antiviral state” in neighboring cells by activating

  2. Self-interest versus group-interest in antiviral control

    NARCIS (Netherlands)

    Boven, M. van; Klinkenberg, D.; Pen, I.; Weissing, F.J.; Heesterbeek, J.A.P.

    2008-01-01

    Antiviral agents have been hailed to hold considerable promise for the treatment and prevention of emerging viral diseases like H5N1 avian influenza and SARS. However, antiviral drugs are not completely harmless, and the conditions under which individuals are willing to participate in a large-scale

  3. Beyond RNAi: antiviral defense strategies in Drosophila and mosquito

    NARCIS (Netherlands)

    Merkling, S.H.; Rij, R.P. van

    2013-01-01

    Virus transmission and spread by arthropods is a major economic and public health concern. The ongoing dissemination of arthropod-borne viruses by blood-feeding insects is an important incentive to study antiviral immunity in these animals. RNA interference is a major mechanism for antiviral defense

  4. Prevalence and chemotherapy-induced reactivation of occult hepatitis B virus among hepatitis B surface antigen negative patients with diffuse large B-cell lymphoma: Significance of hepatitis B core antibodies screening

    Directory of Open Access Journals (Sweden)

    Tamer A. Elbedewy

    2015-03-01

    Conclusion: The study concluded that anti-HBc screening is mandatory before chemotherapy. HBsAg-negative/anti-HBc-positive patients should be closely observed for signs of HBV reactivation through the regular monitoring of ALT. Prophylaxis lamivudine is recommended for anti-HBc positive patients before chemotherapy.

  5. The Antiviral Activities and Mechanisms of Marine Polysaccharides: An Overview

    Science.gov (United States)

    Wang, Wei; Wang, Shi-Xin; Guan, Hua-Shi

    2012-01-01

    Recently, the studies on the antiviral activities of marine natural products, especially marine polysaccharides, are attracting more and more attention all over the world. Marine-derived polysaccharides and their lower molecular weight oligosaccharide derivatives have been shown to possess a variety of antiviral activities. This paper will review the recent progress in research on the antiviral activities and the mechanisms of these polysaccharides obtained from marine organisms. In particular, it will provide an update on the antiviral actions of the sulfated polysaccharides derived from marine algae including carrageenans, alginates, and fucans, relating to their structure features and the structure–activity relationships. In addition, the recent findings on the different mechanisms of antiviral actions of marine polysaccharides and their potential for therapeutic application will also be summarized in detail. PMID:23235364

  6. The Antiviral Activities and Mechanisms of Marine Polysaccharides: An Overview

    Directory of Open Access Journals (Sweden)

    Hua-Shi Guan

    2012-12-01

    Full Text Available Recently, the studies on the antiviral activities of marine natural products, especially marine polysaccharides, are attracting more and more attention all over the world. Marine-derived polysaccharides and their lower molecular weight oligosaccharide derivatives have been shown to possess a variety of antiviral activities. This paper will review the recent progress in research on the antiviral activities and the mechanisms of these polysaccharides obtained from marine organisms. In particular, it will provide an update on the antiviral actions of the sulfated polysaccharides derived from marine algae including carrageenans, alginates, and fucans, relating to their structure features and the structure–activity relationships. In addition, the recent findings on the different mechanisms of antiviral actions of marine polysaccharides and their potential for therapeutic application will also be summarized in detail.

  7. Fatal hepatitis B reactivation treated with entecavir in an isolated anti-HBs positive lymphoma patient: a case report and literature review.

    Science.gov (United States)

    Ferreira, Rosa; Carvalheiro, Joana; Torres, Joana; Fernandes, Alexandra; Giestas, Sílvia; Mendes, Sofia; Agostinho, Cláudia; Campos, Mário J

    2012-01-01

    Hepatitis B virus (HBV) reactivation is a well-recognized complication that occurs in lymphoma patients who undergo chemotherapy. Only very few cases of HBV reactivation in patients with isolated antibody against hepatitis B surface antigen (anti-HBs) have been reported. We present a case of a 78-year-old woman diagnosed with diffuse large B cell non-Hodgkin's lymphoma who only displayed a positive anti-HBs, as the single possible marker of occult HBV infection, before starting therapy. She was treated with several chemotherapeutic regimens (including rituximab) for disease relapses during 3 years. Forty days after the last cycle of chemotherapy, she presented with jaundice, markedly elevated serum aminotransferase levels, and coagulopathy. HBV serology showed positivity for HBsAg, anti-HBc and anti-HBs. HBV DNA was positive. Antiviral treatment with entecavir was promptly initiated, but the patient died from liver failure. A review of the literature of HBV reactivation in patients with detectable anti-HBs levels is discussed.

  8. Monitoring Immune System Function and Reactivation of Latent Viruses in the Artificial Gravity Pilot Study

    Science.gov (United States)

    Mehta, Satish; Crusian, Brian; Pierson, Duane; Sams, Clarence; Stowe, Raymond

    2007-01-01

    Numerous studies have indicated that dysregulation of the immune system occurs during or after spaceflight. Using 21 day -6 deg. head-down tilt bed rest as a spaceflight analog, this study describes the effects of artificial gravity as a daily countermeasure on immunity, stress and reactivation of clinically important latent herpes viruses. The specific aims were to evaluate psychological and physiological stress, to determine the status of the immune system and to quantify reactivation of latent herpes viruses. Blood, saliva, and urine samples were collected from each participating subject at different times throughout the study. An immune assessment was performed on all treatment and control subjects that consisted of a comprehensive peripheral immunophenotype analysis, intracellular cytokine profiles and a measurement of T cell function. The treatment group displayed no differences throughout the course of the study with regards to peripheral leukocyte distribution, cytokine production or T cell function. Shedding of EBV and CMV was quantified by real time PCR in saliva and urine samples, respectively. There was no significant difference in CMV DNA in the treatment group as compared to the control group. EBV and VZV on the other hand showed a mild reactivation during the study. There were no significant differences in plasma cortisol between the control and treatment groups. In addition, no significant differences between antiviral antibody titers (EBV-VCA, -EA, -EBNA, CMV) or tetramer-positive (EBV, CMV) were found between the two groups. EBV DNA copies in blood were typically undetectable but never exceeded 1,500 copies per 10(exp 6) PBMCs. These data indicate that the artificial gravity countermeasure and the 21 day head-down tilt bed rest regimen had no observable adverse effect on immune function.

  9. A profile of cross-reactive neutralizing antibodies against various subtypes of HIV-1 strains in people with HIV-1 infection in Chongqing city%重庆市 HIV-1慢性感染者亚型交叉反应中和抗体的分析

    Institute of Scientific and Technical Information of China (English)

    林怡; 周全华; 张敏; 王韬; 沈方伟; 薛以乐; 王盈; 钟平

    2015-01-01

    Objective To measure the levels of cross-reactive neutralizing antibodies responding to various subtypes of HIV-1 strains in people with HIV-1 infection in Chongqing and to analyze their character-istics.Methods Two hundred and thirty-six plasma samples were collected from patients with chronic HIV-1 infection in Chongqing city.The single-round-infection assay in TZM-bl cells were performed to screen the plasma samples with cross-reactive neutralizing antibodies against various subtypes of HIV-1 strains by using HIV-1 pseudovirus strains and to measure the 50%inhibitory dose ( ID50 ) .Results Eight-een out of 236 (7.63%) plasma samples were able to neutralize various B subtypes and/or C subtypes of HIV-1 pseudovirus strains, among which 15 plasma samples showed the great ability to neutralize pseudovir-us strains of different subtypes.Conclusion The cross-reactive neutralizing antibodies against various sub-types of HIV-1 strains existed in plasma samples collected from people with chronic HIV-1 infection in Chongqing city.%目的:了解重庆市HIV-1感染者体内亚型交叉中和抗体的水平,并分析其特点,为后续表位研究和HIV-1疫苗研制提供科学数据。方法选取重庆市236份HIV-1慢性感染者为研究对象,采用国际通用的假病毒单复制TZM-bl细胞荧光检测系统,使用多个不同亚型的HIV-1假病毒株交叉筛选,对这些血浆样本进行了中和谱筛查和抗体中和能力(ID50)的检测。结果236份血浆样本中,有18份能交叉中和B和C亚型假病毒,占总样本量的7.63%;其中15份样本对多亚型假病毒表现出不同程度的型交叉中和作用。结论重庆市HIV-1慢性感染者血浆样本中存在HIV-1亚型交叉的广谱中和抗体。

  10. Recombinant protein truncation strategy for inducing bactericidal antibodies to the macrophage infectivity potentiator protein of Neisseria meningitidis and circumventing potential cross-reactivity with human FK506-binding proteins.

    Science.gov (United States)

    Bielecka, Magdalena K; Devos, Nathalie; Gilbert, Mélanie; Hung, Miao-Chiu; Weynants, Vincent; Heckels, John E; Christodoulides, Myron

    2015-02-01

    A recombinant macrophage infectivity potentiator (rMIP) protein of Neisseria meningitidis induces significant serum bactericidal antibody production in mice and is a candidate meningococcal vaccine antigen. However, bioinformatics analysis of MIP showed some amino acid sequence similarity to human FK506-binding proteins (FKBPs) in residues 166 to 252 located in the globular domain of the protein. To circumvent the potential concern over generating antibodies that could recognize human proteins, we immunized mice with recombinant truncated type I rMIP proteins that lacked the globular domain and the signal leader peptide (LP) signal sequence (amino acids 1 to 22) and contained the His purification tag at either the N or C terminus (C-term). The immunogenicity of truncated rMIP proteins was compared to that of full (i.e., full-length) rMIP proteins (containing the globular domain) with either an N- or C-terminal His tag and with or without the LP sequence. By comparing the functional murine antibody responses to these various constructs, we determined that C-term His truncated rMIP (-LP) delivered in liposomes induced high levels of antibodies that bound to the surface of wild-type but not Δmip mutant meningococci and showed bactericidal activity against homologous type I MIP (median titers of 128 to 256) and heterologous type II and III (median titers of 256 to 512) strains, thereby providing at least 82% serogroup B strain coverage. In contrast, in constructs lacking the LP, placement of the His tag at the N terminus appeared to abrogate bactericidal activity. The strategy used in this study would obviate any potential concerns regarding the use of MIP antigens for inclusion in bacterial vaccines.

  11. Antiparietal cell antibody test

    Science.gov (United States)

    APCA; Anti-gastric parietal cell antibody; Atrophic gastritis - anti-gastric parietal cell antibody; Gastric ulcer - anti-gastric parietal cell antibody; Pernicious anemia - anti-gastric parietal cell antibody; ...

  12. Reactive Systems

    DEFF Research Database (Denmark)

    Aceto, Luca; Ingolfsdottir, Anna; Larsen, Kim Guldstrand

    A reactive system comprises networks of computing components, achieving their goals through interaction among themselves and their environment. Thus even relatively small systems may exhibit unexpectedly complex behaviours. As moreover reactive systems are often used in safety critical systems......, the need for mathematically based formal methodology is increasingly important. There are many books that look at particular methodologies for such systems. This book offers a more balanced introduction for graduate students and describes the various approaches, their strengths and weaknesses, and when...... they are best used. Milner's CCS and its operational semantics are introduced, together with the notions of behavioural equivalences based on bisimulation techniques and with recursive extensions of Hennessy-Milner logic. In the second part of the book, the presented theories are extended to take timing issues...

  13. The chemical bases of the various AIDS epidemics: recreational drugs, anti-viral chemotherapy and malnutrition

    Indian Academy of Sciences (India)

    Peter Duesberg; Claus Koehnlein; David Rasnick

    2003-06-01

    In 1981 a new epidemic of about two-dozen heterogeneous diseases began to strike non-randomly growing numbers of male homosexuals and mostly male intravenous drug users in the US and Europe. Assuming immunodeficiency as the common denominator the US Centers for Disease Control (CDC) termed the epidemic, AIDS, for acquired immunodeficiency syndrome. From 1981–1984 leading researchers including those from the CDC proposed that recreational drug use was the cause of AIDS, because of exact correlations and of drug-specific diseases. However, in 1984 US government researchers proposed that a virus, now termed human immunodeficiency virus (HIV), is the cause of the non-random epidemics of the US and Europe but also of a new, sexually random epidemic in Africa. The virus-AIDS hypothesis was instantly accepted, but it is burdened with numerous paradoxes, none of which could be resolved by 2003: Why is there no HIV in most AIDS patients, only antibodies against it? Why would HIV take 10 years from infection to AIDS? Why is AIDS not self-limiting via antiviral immunity? Why is there no vaccine against AIDS? Why is AIDS in the US and Europe not random like other viral epidemics? Why did AIDS not rise and then decline exponentially owing to antiviral immunity like all other viral epidemics? Why is AIDS not contagious? Why would only HIV carriers get AIDS who use either recreational or anti-HIV drugs or are subject to malnutrition? Why is the mortality of HIV-antibody-positives treated with anti-HIV drugs 7–9%, but that of all (mostly untreated) HIV-positives globally is only 1.4%? Here we propose that AIDS is a collection of chemical epidemics, caused by recreational drugs, anti-HIV drugs, and malnutrition. According to this hypothesis AIDS is not contagious, not immunogenic, not treatable by vaccines or antiviral drugs, and HIV is just a passenger virus. The hypothesis explains why AIDS epidemics strike non-randomly if caused by drugs and randomly if caused by

  14. The chemical bases of the various AIDS epidemics: recreational drugs, anti-viral chemotherapy and malnutrition.

    Science.gov (United States)

    Duesberg, Peter; Koehnlein, Claus; Rasnick, David

    2003-06-01

    In 1981 a new epidemic of about two-dozen heterogeneous diseases began to strike non-randomly growing numbers of male homosexuals and mostly male intravenous drug users in the US and Europe. Assuming immunodeficiency as the common denominator the US Centers for Disease Control (CDC) termed the epidemic, AIDS, for acquired immunodeficiency syndrome. From 1981-1984 leading researchers including those from the CDC proposed that recreational drug use was the cause of AIDS, because of exact correlations and of drug-specific diseases. However, in 1984 US government researchers proposed that a virus, now termed human immunodeficiency virus (HIV), is the cause of the non-random epidemics of the US and Europe but also of a new, sexually random epidemic in Africa. The virus-AIDS hypothesis was instantly accepted, but it is burdened with numerous paradoxes, none of which could be resolved by 2003: Why is there no HIV in most AIDS patients, only antibodies against it? Why would HIV take 10 years from infection to AIDS? Why is AIDS not self-limiting via antiviral immunity? Why is there no vaccine against AIDS? Why is AIDS in the US and Europe not random like other viral epidemics? Why did AIDS not rise and then decline exponentially owing to antiviral immunity like all other viral epidemics? Why is AIDS not contagious? Why would only HIV carriers get AIDS who use either recreational or anti-HIV drugs or are subject to malnutrition? Why is the mortality of HIV-antibody-positives treated with anti-HIV drugs 7-9%, but that of all (mostly untreated) HIV-positives globally is only 1.4%? Here we propose that AIDS is a collection of chemical epidemics, caused by recreational drugs, anti-HIV drugs, and malnutrition. According to this hypothesis AIDS is not contagious, not immunogenic, not treatable by vaccines or antiviral drugs, and HIV is just a passenger virus. The hypothesis explains why AIDS epidemics strike non-randomly if caused by drugs and randomly if caused by malnutrition

  15. RNAi:antiviral therapy against dengue virus

    Institute of Scientific and Technical Information of China (English)

    Sobia Idrees; Usman A Ashfaq

    2013-01-01

    Dengue virus infection has become a global threat affecting around 100 countries in the world. Currently, there is no licensed antiviral agent available against dengue. Thus, there is a strong need to develop therapeutic strategies that can tackle this life threatening disease. RNA interference is an important and effective gene silencing process which degrades targeted RNA by a sequence specific process. Several studies have been conducted during the last decade to evaluate the efficiency of siRNA in inhibiting dengue virus replication. This review summarizes siRNAs as a therapeutic approach against dengue virus serotypes and concludes that siRNAs against virus and host genes can be next generation treatment of dengue virus infection.

  16. Antifungal and antiviral products of marine organisms.

    Science.gov (United States)

    Cheung, Randy Chi Fai; Wong, Jack Ho; Pan, Wen Liang; Chan, Yau Sang; Yin, Cui Ming; Dan, Xiu Li; Wang, He Xiang; Fang, Evandro Fei; Lam, Sze Kwan; Ngai, Patrick Hung Kui; Xia, Li Xin; Liu, Fang; Ye, Xiu Yun; Zhang, Guo Qing; Liu, Qing Hong; Sha, Ou; Lin, Peng; Ki, Chan; Bekhit, Adnan A; Bekhit, Alaa El-Din; Wan, David Chi Cheong; Ye, Xiu Juan; Xia, Jiang; Ng, Tzi Bun

    2014-04-01

    Marine organisms including bacteria, fungi, algae, sponges, echinoderms, mollusks, and cephalochordates produce a variety of products with antifungal activity including bacterial chitinases, lipopeptides, and lactones; fungal (-)-sclerotiorin and peptaibols, purpurides B and C, berkedrimane B and purpuride; algal gambieric acids A and B, phlorotannins; 3,5-dibromo-2-(3,5-dibromo-2-methoxyphenoxy)phenol, spongistatin 1, eurysterols A and B, nortetillapyrone, bromotyrosine alkaloids, bis-indole alkaloid, ageloxime B and (-)-ageloxime D, haliscosamine, hamigeran G, hippolachnin A from sponges; echinoderm triterpene glycosides and alkene sulfates; molluscan kahalalide F and a 1485-Da peptide with a sequence SRSELIVHQR; and cepalochordate chitotriosidase and a 5026.9-Da antifungal peptide. The antiviral compounds from marine organisms include bacterial polysaccharide and furan-2-yl acetate; fungal macrolide, purpurester A, purpurquinone B, isoindolone derivatives, alterporriol Q, tetrahydroaltersolanol C and asperterrestide A, algal diterpenes, xylogalactofucan, alginic acid, glycolipid sulfoquinovosyldiacylglycerol, sulfated polysaccharide p-KG03, meroditerpenoids, methyl ester derivative of vatomaric acid, lectins, polysaccharides, tannins, cnidarian zoanthoxanthin alkaloids, norditerpenoid and capilloquinol; crustacean antilipopolysaccharide factors, molluscan hemocyanin; echinoderm triterpenoid glycosides; tunicate didemnin B, tamandarins A and B and; tilapia hepcidin 1-5 (TH 1-5), seabream SauMx1, SauMx2, and SauMx3, and orange-spotted grouper β-defensin. Although the mechanisms of antifungal and antiviral activities of only some of the aforementioned compounds have been elucidated, the possibility to use those known to have distinctly different mechanisms, good bioavailability, and minimal toxicity in combination therapy remains to be investigated. It is also worthwhile to test the marine antimicrobials for possible synergism with existing drugs. The prospects of

  17. Atividade antiviral de Musa acuminata Colla, Musaceae Antiviral activity of Musa acuminata Colla, Musaceae

    Directory of Open Access Journals (Sweden)

    Fernanda Otaviano Martins

    2009-09-01

    Full Text Available O presente trabalho avalia a atividade antiviral de extratos e frações de Musa acuminata Colla, Musaceae, coletada em duas regiões do Estado do Rio de Janeiro (Petrópolis e Santo Antônio de Pádua. As inflorescências de M. acuminata apresentaram excelente atividade para os dois vírus avaliados: herpesvírus simples humano tipo 1 e herpesvírus simples humano tipo 2, ambos resistentes ao Aciclovir. Os resultados indicam que os extratos de M. acuminata testados podem constituir alvo potencial para uso em terapias antivirais.This study evaluates the antiviral activity of extracts and fractions of Musa acuminata Colla collected in two regions of Rio de Janeiro State (Petrópolis and Santo Antônio de Pádua. The inflorescences of M. acuminata showed excellent activity for the two virus evaluated: simple human herpesvirus type 1 and simple human herpesvirus type 2, both resistant to Acyclovir. The results indicate that the tested extracts of M. acuminata can be potential target for use in antiviral therapy.

  18. Cherry Valley ducks mitochondrial antiviral-signaling protein (MAVS mediated signaling pathway and antiviral activity research

    Directory of Open Access Journals (Sweden)

    Ning Li

    2016-09-01

    Full Text Available Mitochondrial antiviral-signaling protein (MAVS, an adaptor protein of retinoic acid-inducible gene I (RIG-I like receptors (RLRs-mediated signal pathway, is involved in innate immunity. In this study, Cherry Valley duck MAVS (duMAVS was cloned from the spleen and analyzed. duMAVS was determined to have a caspase activation and recruitment domain at N-terminal, followed by a proline rich domain and a transmembrane domain at C-terminal. Quantitative real time PCR indicated that duMAVS was expressed in all tissues tested across a broad expression spectrum. The expression of duMAVS was significantly up-regulated after infection with duck Tembusu virus. Overexpression of duMAVS could drive the activation of interferon-β, nuclear factor-κB, interferon regulatory factor 7, and many downstream factors (such as Mx, PKR, OAS, and IL-8 in duck embryo fibroblast cells. What’s more, RNA interference further confirmed that duMAVS was an important adaptor for IFN-β activation. The antiviral assay showed that duMAVS could suppress the various viral replications (duck Tembusu virus, novel reovirus, and duck plague virus at early stages of infection. Overall, these results showed that the main signal pathway mediated by duMAVS and it had a broad-spectrum antiviral ability. This research will be helpful to better understanding the innate immune system of ducks.

  19. Isolation and characterisation of a human-like antibody fragment (scFv that inactivates VEEV in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Torsten Rülker

    Full Text Available Venezuelan equine encephalitis virus (VEEV belongs to the Alphavirus genus and several species of this family are pathogenic to humans. The viruses are classified as potential agents of biological warfare and terrorism and sensitive detection as well as effective prophylaxis and antiviral therapies are required.In this work, we describe the isolation of the anti-VEEV single chain Fragment variable (scFv, ToR67-3B4, from a non-human primate (NHP antibody gene library. We report its recloning into the bivalent scFv-Fc format and further immunological and biochemical characterisation.The scFv-Fc ToR67-3B4 recognised viable as well as formalin and ß-propionolactone (ß-Pl inactivated virus particles and could be applied for immunoblot analysis of VEEV proteins and immuno-histochemistry of VEEV infected cells. It detected specifically the viral E1 envelope protein of VEEV but did not react with reduced viral glycoprotein preparations suggesting that recognition depends upon conformational epitopes. The recombinant antibody was able to detect multiple VEEV subtypes and displayed only marginal cross-reactivity to other Alphavirus species except for EEEV. In addition, the scFv-Fc fusion described here might be of therapeutic use since it successfully inactivated VEEV in a murine disease model. When the recombinant antibody was administered 6 hours post challenge, 80% to 100% of mice survived lethal VEEV IA/B or IE infection. Forty to sixty percent of mice survived when scFv-Fc ToR67-3B4 was applied 6 hours post challenge with VEEV subtypes II and former IIIA. In combination with E2-neutralising antibodies the NHP antibody isolated here could significantly improve passive protection as well as generic therapy of VEE.

  20. Fibrotic remodeling of the extracellular matrix through a novel (engineered, dual-function antibody reactive to a cryptic epitope on the N-terminal 30 kDa fragment of fibronectin.

    Directory of Open Access Journals (Sweden)

    Maryada Sharma

    Full Text Available Fibrosis is characterized by excessive accumulation of scar tissue as a result of exaggerated deposition of extracellular matrix (ECM, leading to tissue contraction and impaired function of the organ. Fibronectin (Fn is an essential component of the ECM, and plays an important role in fibrosis. One such fibrotic pathology is that of proliferative vitreoretinopathy (PVR, a sight-threatening complication which develops as a consequence of failure of surgical repair of retinal detachment. Such patients often require repeated surgeries for retinal re-attachment; therefore, a preventive measure for PVR is of utmost importance. The contractile membranes formed in PVR, are composed of various cell types including the retinal pigment epithelial cells (RPE; fibronectin is an important constituent of the ECM surrounding these cells. Together with the vitreous, fibronectin creates microenvironments in which RPE cells proliferate. We have successfully developed a dual-action, fully human, fibronectin-specific single chain variable fragment antibody (scFv termed Fn52RGDS, which acts in two ways: i binds to cryptic sites in fibronectin, and thereby prevents its self polymerization/fibrillogenesis, and ii interacts with the cell surface receptors, ie., integrins (through an attached "RGD" sequence tag, and thereby blocks the downstream cell signaling events. We demonstrate the ability of this antibody to effectively reduce some of the hallmark features of fibrosis--migration, adhesion, fibronectin polymerization, matrix metalloprotease (MMP expression, as well as reduction of collagen gel contraction (a model of fibrotic tissue remodeling. The data suggests that the antibody can be used as a rational, novel anti-fibrotic candidate.

  1. Immunocytochemical and Immunohistochemical Staining with Peptide Antibodies.

    Science.gov (United States)

    Friis, Tina; Pedersen, Klaus Boberg; Hougaard, David; Houen, Gunnar

    2015-01-01

    Peptide antibodies are particularly useful for immunocytochemistry (ICC) and immunohistochemistry (IHC), where antigens may denature due to fixation of tissues and cells. Peptide antibodies can be made to any defined sequence, including unknown putative proteins and posttranslationally modified sequences. Moreover, the availability of large amounts of the antigen (peptide) allows inhibition/adsorption controls, which are important in ICC/IHC, due to the many possibilities for false-positive reactions caused by immunoglobulin Fc receptors, nonspecific reactions, and cross-reactivity of primary and secondary antibodies with other antigens and endogenous immunoglobulins, respectively. Here, simple protocols for ICC and IHC are described together with recommendations for appropriate controls.

  2. An antiviral protein from Bougainvillea spectabilis roots; purification and characterisation.

    Science.gov (United States)

    Balasaraswathi, R; Sadasivam, S; Ward, M; Walker, J M

    1998-04-01

    An antiviral protein active against mechanical transmission of tomato spotted wilt virus was identified in the root tissues of Bougainvillea spectabilis Willd. Bougainvillea Antiviral Protein I (BAP I) was purified to apparent homogeneity from the roots of Bougainvillea by ammonium sulphate precipitation, CM- and DEAE-Sepharose chromatography and reverse phase HPLC. BAP I is a highly basic protein (pI value > 8.6) with an Mr of 28,000. The N-terminal sequence of BAP I showed homology with other plant antiviral proteins. Preliminary tests suggest that purified BAP I is capable of interfering with in vitro protein synthesis.

  3. What Is Reactive Arthritis?

    Science.gov (United States)

    ... Arthritis PDF Version Size: 69 KB November 2014 What is Reactive Arthritis? Fast Facts: An Easy-to- ... Information About Reactive Arthritis and Other Related Conditions What Causes Reactive Arthritis? Sometimes, reactive arthritis is set ...

  4. Antibody-dependent enhancement of dengue virus infection is inhibited by SA-17, a doxorubicin derivative

    NARCIS (Netherlands)

    Ayala Nunez, Vanesa; Jarupathirun, Patsaporn; Kaptein, Suzanne; Neyts, Johan; Smit, Jolanda

    2013-01-01

    Antibody-dependent enhancement (ADE) is thought to play a critical role in the exacerbation of dengue virus (DENV)-induced disease during a heterologous re-infection. Despite ADE's clinical impact, only a few antiviral compounds have been assessed for their anti-ADE activity. We reported earlier tha

  5. Randomized phase I: safety, immunogenicity and mucosal antiviral activity in young healthy women vaccinated with HIV-1 Gp41 P1 peptide on virosomes

    OpenAIRE

    Geert Leroux-Roels; Cathy Maes; Frédéric Clement; Frank van Engelenburg; Marieke van den Dobbelsteen; Michael Adler; Mario Amacker; Lucia Lopalco; Morgane Bomsel; Anick Chalifour; Sylvain Fleury

    2013-01-01

    UNLABELLED: Mucosal antibodies harboring various antiviral activities may best protect mucosal surfaces against early HIV-1 entry at mucosal sites and they should be ideally induced by prophylactic HIV-1 vaccines for optimal prevention of sexually transmitted HIV-1. A phase I, double-blind, randomized, placebo-controlled trial was conducted in twenty-four healthy HIV-uninfected young women. The study objectives were to assess the safety, tolerability and immunogenicity of virosomes harboring ...

  6. The antiviral response to gamma interferon.

    Science.gov (United States)

    Costa-Pereira, Ana P; Williams, Timothy M; Strobl, Birgit; Watling, Diane; Briscoe, James; Kerr, Ian M

    2002-09-01

    A role for alpha/beta interferon (IFN-alpha/beta) in the IFN-gamma antiviral response has long been suggested. Accordingly, possible roles for autocrine or double-stranded-RNA (dsRNA)-induced IFN-alpha/beta in the IFN-gamma response were investigated. Use was made of wild-type and a variety of mutant human fibrosarcoma cell lines, including mutant U5A cells, which lack a functional IFN-alpha/beta receptor and hence an IFN-alpha/beta response. IFN-gamma did not induce detectable levels of IFN-alpha/beta in any of the cell lines, nor was the IFN-gamma response per se dependent on autocrine IFN-alpha/beta. On the other hand, a number of responses to dsRNA [poly(I). poly(C)] and encephalomyocarditis virus were greatly enhanced by IFN-gamma pretreatment (priming) of wild-type cells or of mutant cells lacking an IFN-alpha/beta response; these include the primary induction of dsRNA-inducible mRNAs, including IFN-beta mRNA, and, to a lesser extent, the dsRNA-mediated activation of the p38 mitogen-activated protein (MAP) kinase(s). IFN-gamma priming of mRNA induction by dsRNA is dependent on JAK1 and shows biphasic kinetics, with an initial rapid (<30-min) response being followed by a more substantial effect on overnight incubation. The IFN-gamma-primed dsRNA responses appear to be subject to modulation through the p38, phosphatidylinositol 3-kinase, and ERK1/ERK2 MAP kinase pathways. It can be concluded that despite efficient priming of IFN-beta production, the IFN-alpha/beta pathways play no significant role in the primary IFN-gamma antiviral response in these cell-virus systems. The observed IFN-gamma priming of dsRNA responses, on the other hand, will likely play a significant role in combating virus infection in vivo.

  7. Antigen-Specific Antibody Glycosylation Is Regulated via Vaccination.

    Science.gov (United States)

    Mahan, Alison E; Jennewein, Madeleine F; Suscovich, Todd; Dionne, Kendall; Tedesco, Jacquelynne; Chung, Amy W; Streeck, Hendrik; Pau, Maria; Schuitemaker, Hanneke; Francis, Don; Fast, Patricia; Laufer, Dagna; Walker, Bruce D; Baden, Lindsey; Barouch, Dan H; Alter, Galit

    2016-03-01

    Antibody effector functions, such as antibody-dependent cellular cytotoxicity, complement deposition, and antibody-dependent phagocytosis, play a critical role in immunity against multiple pathogens, particularly in the absence of neutralizing activity. Two modifications to the IgG constant domain (Fc domain) regulate antibody functionality: changes in antibody subclass and changes in a single N-linked glycan located in the CH2 domain of the IgG Fc. Together, these modifications provide a specific set of instructions to the innate immune system to direct the elimination of antibody-bound antigens. While it is clear that subclass selection is actively regulated during the course of natural infection, it is unclear whether antibody glycosylation can be tuned, in a signal-specific or pathogen-specific manner. Here, we show that antibody glycosylation is determined in an antigen- and pathogen-specific manner during HIV infection. Moreover, while dramatic differences exist in bulk IgG glycosylation among individuals in distinct geographical locations, immunization is able to overcome these differences and elicit antigen-specific antibodies with similar antibody glycosylation patterns. Additionally, distinct vaccine regimens induced different antigen-specific IgG glycosylation profiles, suggesting that antibody glycosylation is not only programmable but can be manipulated via the delivery of distinct inflammatory signals during B cell priming. These data strongly suggest that the immune system naturally drives antibody glycosylation in an antigen-specific manner and highlights a promising means by which next-generation therapeutics and vaccines can harness the antiviral activity of the innate immune system via directed alterations in antibody glycosylation in vivo.  .

  8. Antigen-Specific Antibody Glycosylation Is Regulated via Vaccination.

    Directory of Open Access Journals (Sweden)

    Alison E Mahan

    2016-03-01

    Full Text Available Antibody effector functions, such as antibody-dependent cellular cytotoxicity, complement deposition, and antibody-dependent phagocytosis, play a critical role in immunity against multiple pathogens, particularly in the absence of neutralizing activity. Two modifications to the IgG constant domain (Fc domain regulate antibody functionality: changes in antibody subclass and changes in a single N-linked glycan located in the CH2 domain of the IgG Fc. Together, these modifications provide a specific set of instructions to the innate immune system to direct the elimination of antibody-bound antigens. While it is clear that subclass selection is actively regulated during the course of natural infection, it is unclear whether antibody glycosylation can be tuned, in a signal-specific or pathogen-specific manner. Here, we show that antibody glycosylation is determined in an antigen- and pathogen-specific manner during HIV infection. Moreover, while dramatic differences exist in bulk IgG glycosylation among individuals in distinct geographical locations, immunization is able to overcome these differences and elicit antigen-specific antibodies with similar antibody glycosylation patterns. Additionally, distinct vaccine regimens induced different antigen-specific IgG glycosylation profiles, suggesting that antibody glycosylation is not only programmable but can be manipulated via the delivery of distinct inflammatory signals during B cell priming. These data strongly suggest that the immune system naturally drives antibody glycosylation in an antigen-specific manner and highlights a promising means by which next-generation therapeutics and vaccines can harness the antiviral activity of the innate immune system via directed alterations in antibody glycosylation in vivo.  .

  9. Antiviral activity and mechanism of action of arbidol against Hantaan ...

    African Journals Online (AJOL)

    Methods: HUVEC cells infected with HTNV 76-118 were treated with serially diluted arbidol solutions at. -2h (2 h before viral infection, .... murine leukemia virus (M-MLV) Reverse .... DISCUSSION. Arbidol is a small antiviral compound with a.

  10. Regulation of antiviral innate immunity by deubiquitinase CYLD

    Institute of Scientific and Technical Information of China (English)

    Minying Zhang; Andrew J Lee; Xuefeng Wu; Shao-Cong Sun

    2011-01-01

    An antiviral innate immune response involves induction of type Ⅰ interferons (IFNs) and their subsequent autocrine and paracrine actions,but the underlying regulatory mechanisms are incompletely understood.Here we report that CYLD,a deubiquitinase that specifically digests lysine 63-1inked ubiquitin chains,is required for antiviral host defense.Loss of CYLD renders mice considerably more susceptible to infection by vesicular stomatitis virus (VSV).Consistently,CYLD-deficient dendritic cells are more sensitive to VSV infection.This functional defect was not due to lack of type I IFN production but rather because of attenuated IFN receptor signaling.In the absence of CYLD,IFN-β is ineffective in the induction of antiviral genes and protection of cells from viral infection.These findings establish CYLD as a novel regulator of antiviral innate immunity and suggest a role for CYLD in regulating IFN receptor signaling.

  11. Anti-viral Effect of Caulis Tripterygii Wilfordii

    Institute of Scientific and Technical Information of China (English)

    WU Guo-qin

    2005-01-01

    @@ There have appeared more and more antibiotics to antagonize against causative organism, but in comparison few antivirals have. Hence, many viral diseases remain refractory and fatal due to lack of effective medicine.

  12. Antiviral chemotherapy in veterinary medicine: current applications and perspectives.

    Science.gov (United States)

    Dal Pozzo, F; Thiry, E

    2014-12-01

    The current situation in the use of antiviral drugs in veterinary medicine is characterised by a novel and optimistic approach.Viruses of veterinary importance are still used as animal models in the developmentof human therapeutics, but there is growing interest in many of these viruses in the identification of antiviral molecules for use in both livestock and companion animals. The use of antiviral drugs in livestock animals is envisaged for the treatment or control of disease on a large scale (mass treatment), whereas in companion animals an individual approach is favoured. An overview of the most recent examples of research in the use of antivirals in veterinary medicine is presented, with particular emphasis on their in vivo applications.

  13. STUDY OF ANTIVIRAL ACTIVITY OF SOME HYDRAZONE PINOSTROBIN DERIVATIVES

    Directory of Open Access Journals (Sweden)

    G. K. Mukusheva

    2014-01-01

    Full Text Available New derivatives on the basis of hydrazone pinostrobin molecule were synthesized. Significant antiviral activity of received samples of new hydrazone pinstrobin derivatives was identified.

  14. Anti-tumor and anti-viral activities of Galanthus nivalis agglutinin (GNA)-related lectins.

    Science.gov (United States)

    Wu, Lei; Bao, Jin-Ku

    2013-04-01

    Galanthus nivalis agglutinin (GNA)-related lectin family, a superfamily of strictly mannose-binding specific lectins widespread among monocotyledonous plants, is well-known to possess a broad range of biological functions such as anti-tumor, anti-viral and anti-fungal activities. Herein, we mainly focused on exploring the precise molecular mechanisms by which GNA-related lectins induce cancer cell apoptotic and autophagic death targeting mitochondria-mediated ROS-p38-p53 apoptotic or autophagic pathway, Ras-Raf and PI3K-Akt anti-apoptotic or anti-autophagic pathways. In addition, we further discussed the molecular mechanisms of GNA-related lectins exerting anti-viral activities by blocking the entry of the virus into its target cells, preventing transmission of the virus as well as forcing virus to delete glycan in its envelope protein and triggering neutralizing antibody. In conclusion, these findings may provide a new perspective of GNA-related lectins as potential drugs for cancer and virus therapeutics in the future.

  15. Impact of Desensitization on Antiviral Immunity in HLA-Sensitized Kidney Transplant Recipients

    Science.gov (United States)

    Shin, Bong-Ha; Ge, Shili; Mirocha, James; Thomas, David; Chu, Maggie; Rodriguez, Edgar; Chao, Christine; Petrosyan, Anna; Galera, Odette A.; Vo, Ashley; Choi, Jua; Peng, Alice; Kahwaji, Joseph; Jordan, Stanley C.

    2017-01-01

    Viral infections represent significant morbidity and mortality factors in kidney transplant recipients, with CMV, EBV, and BKV infections being most common. Desensitization (DES) with IVIg and rituximab with/without plasma exchange followed by kidney transplantation with alemtuzumab induction increased successful transplant rates in HLA-sensitized patients but may represent an increased risk for viral infections due to severe lymphocyte depletion. Here, we report on the posttransplant viral infection status in 372 DES versus 538 non-DES patients. CMV and EBV viremia were significantly lower in DES patients, while BKV viremia was similar. This trend was observed primarily in CMV sero(−), EBV sero(+), and sero(−) patients. No patient developed PTLD. The incidence of BKAN, allograft, and patient survival was similar in both groups. These viral infections were not associated with subsequent allograft rejection which occurred within 6 months after the infection. Conclusions. The IVIg + rituximab desensitization combined with alemtuzumab induction with triple immunosuppression maintenance does not increase the risk for CMV, EBV, and BKV infections. Possible factors include, in addition to posttransplant antiviral prophylaxis and PCR monitoring, presence of memory T cells and antibodies specific to CMV and likely EBV, NK cell-mediated ADCC despite lymphocyte depletion, elimination of EBV and CMV reservoirs by rituximab and alemtuzumab, and use of IVIg with antiviral properties.

  16. Human cytomegaloviruses expressing yellow fluorescent fusion proteins--characterization and use in antiviral screening.

    Science.gov (United States)

    Straschewski, Sarah; Warmer, Martin; Frascaroli, Giada; Hohenberg, Heinrich; Mertens, Thomas; Winkler, Michael

    2010-02-11

    Recombinant viruses labelled with fluorescent proteins are useful tools in molecular virology with multiple applications (e.g., studies on intracellular trafficking, protein localization, or gene activity). We generated by homologous recombination three recombinant cytomegaloviruses carrying the enhanced yellow fluorescent protein (EYFP) fused with the viral proteins IE-2, ppUL32 (pp150), and ppUL83 (pp65). In growth kinetics, the three viruses behaved all like wild type, even at low multiplicity of infection (MOI). The expression of all three fusion proteins was detected, and their respective localizations were the same as for the unmodified proteins in wild-type virus-infected cells. We established the in vivo measurement of fluorescence intensity and used the recombinant viruses to measure inhibition of viral replication by neutralizing antibodies or antiviral substances. The use of these viruses in a pilot screen based on fluorescence intensity and high-content analysis identified cellular kinase inhibitors that block viral replication. In summary, these viruses with individually EYFP-tagged proteins will be useful to study antiviral substances and the dynamics of viral infection in cell culture.

  17. Human cytomegaloviruses expressing yellow fluorescent fusion proteins--characterization and use in antiviral screening.

    Directory of Open Access Journals (Sweden)

    Sarah Straschewski

    Full Text Available Recombinant viruses labelled with fluorescent proteins are useful tools in molecular virology with multiple applications (e.g., studies on intracellular trafficking, protein localization, or gene activity. We generated by homologous recombination three recombinant cytomegaloviruses carrying the enhanced yellow fluorescent protein (EYFP fused with the viral proteins IE-2, ppUL32 (pp150, and ppUL83 (pp65. In growth kinetics, the three viruses behaved all like wild type, even at low multiplicity of infection (MOI. The expression of all three fusion proteins was detected, and their respective localizations were the same as for the unmodified proteins in wild-type virus-infected cells. We established the in vivo measurement of fluorescence intensity and used the recombinant viruses to measure inhibition of viral replication by neutralizing antibodies or antiviral substances. The use of these viruses in a pilot screen based on fluorescence intensity and high-content analysis identified cellular kinase inhibitors that block viral replication. In summary, these viruses with individually EYFP-tagged proteins will be useful to study antiviral substances and the dynamics of viral infection in cell culture.

  18. ATM facilitates mouse gammaherpesvirus reactivation from myeloid cells during chronic infection.

    Science.gov (United States)

    Kulinski, Joseph M; Darrah, Eric J; Broniowska, Katarzyna A; Mboko, Wadzanai P; Mounce, Bryan C; Malherbe, Laurent P; Corbett, John A; Gauld, Stephen B; Tarakanova, Vera L

    2015-09-01

    Gammaherpesviruses are cancer-associated pathogens that establish life-long infection in most adults. Insufficiency of Ataxia-Telangiectasia mutated (ATM) kinase leads to a poor control of chronic gammaherpesvirus infection via an unknown mechanism that likely involves a suboptimal antiviral response. In contrast to the phenotype in the intact host, ATM facilitates gammaherpesvirus reactivation and replication in vitro. We hypothesized that ATM mediates both pro- and antiviral activities to regulate chronic gammaherpesvirus infection in an immunocompetent host. To test the proposed proviral activity of ATM in vivo, we generated mice with ATM deficiency limited to myeloid cells. Myeloid-specific ATM deficiency attenuated gammaherpesvirus infection during the establishment of viral latency. The results of our study uncover a proviral role of ATM in the context of gammaherpesvirus infection in vivo and support a model where ATM combines pro- and antiviral functions to facilitate both gammaherpesvirus-specific T cell immune response and viral reactivation in vivo.

  19. The mutation Glu151Asp in the B-component of the Bacillus cereus non-hemolytic enterotoxin (Nhe) leads to a diverging reactivity in antibody-based detection systems.

    Science.gov (United States)

    Didier, Andrea; Jeßberger, Nadja; Krey, Victoria; Dietrich, Richard; Scherer, Siegfried; Märtlbauer, Erwin

    2015-11-09

    The ability of Bacillus cereus to cause foodborne toxicoinfections leads to increasing concerns regarding consumer protection. For the diarrhea-associated enterotoxins, the assessment of the non-hemolytic enterotoxin B (NheB) titer determined by a sandwich enzyme immunoassay (EIA) correlates best with in vitro cytotoxicity. In general, the regulation of enterotoxin expression of B. cereus is a coordinately-regulated process influenced by environmental, and probably also by host factors. As long as these factors are not completely understood, the currently-applied diagnostic procedures are based on indirect approaches to assess the potential virulence of an isolate. To date, sandwich EIA results serve as a surrogate marker to categorize isolates as either potentially low or highly toxic. Here, we report on a single amino acid exchange in the NheB sequence leading to an underestimation of the cytotoxic potential in a limited number of strains. During the screening of a large panel of B. cereus isolates, six showed uncommon features with low sandwich EIA titers despite high cytotoxicity. Sequence analysis revealed the point-mutation (Glu)151(Asp) in the potential binding region of the capture antibody. Application of this antibody also results in low titers in an indirect EIA format and shows variable detection intensities in Western-immunoblots. A commercially-available assay based on a lateral flow device detects all strains correctly as NheB producers in a qualitative manner. In conclusion, isolates showing low NheB titers should additionally be assayed in an indirect EIA or for their in vitro cytotoxicity to ensure a correct classification as either low or highly toxic.

  20. The Mutation Glu151Asp in the B-Component of the Bacillus cereus Non-Hemolytic Enterotoxin (Nhe Leads to a Diverging Reactivity in Antibody-Based Detection Systems

    Directory of Open Access Journals (Sweden)

    Andrea Didier

    2015-11-01

    Full Text Available The ability of Bacillus cereus to cause foodborne toxicoinfections leads to increasing concerns regarding consumer protection. For the diarrhea-associated enterotoxins, the assessment of the non-hemolytic enterotoxin B (NheB titer determined by a sandwich enzyme immunoassay (EIA correlates best with in vitro cytotoxicity. In general, the regulation of enterotoxin expression of B. cereus is a coordinately-regulated process influenced by environmental, and probably also by host factors. As long as these factors are not completely understood, the currently-applied diagnostic procedures are based on indirect approaches to assess the potential virulence of an isolate. To date, sandwich EIA results serve as a surrogate marker to categorize isolates as either potentially low or highly toxic. Here, we report on a single amino acid exchange in the NheB sequence leading to an underestimation of the cytotoxic potential in a limited number of strains. During the screening of a large panel of B. cereus isolates, six showed uncommon features with low sandwich EIA titers despite high cytotoxicity. Sequence analysis revealed the point-mutation Glu151Asp in the potential binding region of the capture antibody. Application of this antibody also results in low titers in an indirect EIA format and shows variable detection intensities in Western-immunoblots. A commercially-available assay based on a lateral flow device detects all strains correctly as NheB producers in a qualitative manner. In conclusion, isolates showing low NheB titers should additionally be assayed in an indirect EIA or for their in vitro cytotoxicity to ensure a correct classification as either low or highly toxic.

  1. Antiviral resistance and the control of pandemic influenza.

    Directory of Open Access Journals (Sweden)

    Marc Lipsitch

    2007-01-01

    Full Text Available The response to the next influenza pandemic will likely include extensive use of antiviral drugs (mainly oseltamivir, combined with other transmission-reducing measures. Animal and in vitro studies suggest that some strains of influenza may become resistant to oseltamivir while maintaining infectiousness (fitness. Use of antiviral agents on the scale anticipated for the control of pandemic influenza will create an unprecedented selective pressure for the emergence and spread of these strains. Nonetheless, antiviral resistance has received little attention when evaluating these plans.We designed and analyzed a deterministic compartmental model of the transmission of oseltamivir-sensitive and -resistant influenza infections during a pandemic. The model predicts that even if antiviral treatment or prophylaxis leads to the emergence of a transmissible resistant strain in as few as 1 in 50,000 treated persons and 1 in 500,000 prophylaxed persons, widespread use of antivirals may strongly promote the spread of resistant strains at the population level, leading to a prevalence of tens of percent by the end of a pandemic. On the other hand, even in circumstances in which a resistant strain spreads widely, the use of antivirals may significantly delay and/or reduce the total size of the pandemic. If resistant strains carry some fitness cost, then, despite widespread emergence of resistance, antivirals could slow pandemic spread by months or more, and buy time for vaccine development; this delay would be prolonged by nondrug control measures (e.g., social distancing that reduce transmission, or use of a stockpiled suboptimal vaccine. Surprisingly, the model suggests that such nondrug control measures would increase the proportion of the epidemic caused by resistant strains.The benefits of antiviral drug use to control an influenza pandemic may be reduced, although not completely offset, by drug resistance in the virus. Therefore, the risk of resistance

  2. Phytochemical, antioxidant, antiviral and cytotoxic evaluation of Opuntia dillenii flowers

    OpenAIRE

    Arthanari Saravana Kumar; Mani Ganesh; Mei Mei Peng; Jang Hyun Tae

    2014-01-01

    Opuntia dillenii used in Asian traditional medicine especially in China. We here report on the investigation of the phytochemical content, antioxidant, cytotoxicity and antiviral activity of methanolic extract of O. dillenii flowers. The antioxidant activity was measured with the DPPH, hydrogen peroxide and hydroxyl radicals scavenging method. In the antiviral and cytotoxic assay we used different viruses in different cell lines. In antioxidant assay, the DPPH assay exhibited potent antioxid...

  3. Diagnosis and antiviral intervention strategies for mitigating an influenza epidemic.

    Directory of Open Access Journals (Sweden)

    Robert Moss

    Full Text Available BACKGROUND: Many countries have amassed antiviral stockpiles for pandemic preparedness. Despite extensive trial data and modelling studies, it remains unclear how to make optimal use of antiviral stockpiles within the constraints of healthcare infrastructure. Modelling studies informed recommendations for liberal antiviral distribution in the pandemic phase, primarily to prevent infection, but failed to account for logistical constraints clearly evident during the 2009 H1N1 outbreaks. Here we identify optimal delivery strategies for antiviral interventions accounting for logistical constraints, and so determine how to improve a strategy's impact. METHODS AND FINDINGS: We extend an existing SEIR model to incorporate finite diagnostic and antiviral distribution capacities. We evaluate the impact of using different diagnostic strategies to decide to whom antivirals are delivered. We then determine what additional capacity is required to achieve optimal impact. We identify the importance of sensitive and specific case ascertainment in the early phase of a pandemic response, when the proportion of false-positive presentations may be high. Once a substantial percentage of ILI presentations are caused by the pandemic strain, identification of cases for treatment on syndromic grounds alone results in a greater potential impact than a laboratory-dependent strategy. Our findings reinforce the need for a decentralised system capable of providing timely prophylaxis. CONCLUSIONS: We address specific real-world issues that must be considered in order to improve pandemic preparedness policy in a practical and methodologically sound way. Provision of antivirals on the scale proposed for an effective response is infeasible using traditional public health outbreak management and contact tracing approaches. The results indicate to change the transmission dynamics of an influenza epidemic with an antiviral intervention, a decentralised system is required for

  4. Latent Virus Reactivation: From Space to Earth

    Science.gov (United States)

    Mehta, Satish K.; Cohrs, Randall J.; Gilden, Donald H.; Tyring, Stephen K.; Castro, Victoria A.; Ott, C. Mark; Pierson, Duane L.

    2010-01-01

    Reactivation of latent viruses is a recognized consequence of decreased immunity. More recently viral reactivation has been identified as an important in vivo indicator of clinically relevant immune changes. Viral reactivation can be determined quickly and easily by the presence of virus in saliva and other body fluids. Real-time polymerase chain reaction (PCR) is a highly sensitive and specific molecular method to detect the presence of specific viral DNA. Studies in astronauts demonstrated that herpes simplex virus type 1(HSV-1), Epstein-Barr Virus (EBV), cytomegalovirus (CMV), and varicella zoster virus (VZV) reactivate at rates above normal during and after spaceflight in response to moderately decreased T-cell immunity. This technology was expanded to patients on Earth beginning with human immune deficiency virus (HIV) immuno-compromised patients. The HIV patients shed EBV in saliva at rates 9-fold higher than observed in astronauts demonstrating that the level of EBV shedding reflects the severity of impaired immunity. Whereas EBV reactivation is not expected to produce serious effects in astronauts on missions of 6 months or less, VZV reactivation in astronauts could produce shingles. Reactivation of live, infectious VZV in astronauts with no symptoms was demonstrated in astronauts during and after spaceflight. We applied our technology to study VZV-induced shingles in patients. In a study of 54 shingles patients, we showed salivary VZV was present in every patient on the day antiviral (acyclovir) treatment was initiated. Pain and skin lesions decreased with antiviral treatment. Corresponding decreases in levels of VZV were also observed and accompanied recovery. Although the level of VZV in shingles patients before the treatment was generally higher than those found in astronauts, lower range of VZV numbers in shingles patients overlapped with astronaut s levels. This suggests a potential risk of shingles to astronauts resulting from reactivation of VZV. In

  5. Latent Virus Reactivation: From Space to Earth

    Science.gov (United States)

    Mehta, Satish K.; Cohrs, Randall J.; Gilden, Donald H.; Tyring, Stephen K.; Castro, Victoria A.; Ott, C. Mark; Pierson, Duane L.

    2010-01-01

    Reactivation of latent viruses is a recognized consequence of decreased immunity. More recently viral reactivation has been identified as an important in vivo indicator of clinically relevant immune changes. Viral reactivation can be determined quickly and easily by the presence of virus in saliva and other body fluids. Real-time polymerase chain reaction (PCR) is a highly sensitive and specific molecular method to detect the presence of specific viral DNA. Studies in astronauts demonstrated that herpes simplex virus type 1(HSV-1), Epstein-Barr Virus (EBV), cytomegalovirus (CMV), and varicella zoster virus (VZV) reactivate at rates above normal during and after spaceflight in response to moderately decreased T-cell immunity. This technology was expanded to patients on Earth beginning with human immune deficiency virus (HIV) immuno-compromised patients. The HIV patients shed EBV in saliva at rates 9-fold higher than observed in astronauts demonstrating that the level of EBV shedding reflects the severity of impaired immunity. Whereas EBV reactivation is not expected to produce serious effects in astronauts on missions of 6 months or less, VZV reactivation in astronauts could produce shingles. Reactivation of live, infectious VZV in astronauts with no symptoms was demonstrated in astronauts during and after spaceflight. We applied our technology to study VZV-induced shingles in patients. In a study of 54 shingles patients, we showed salivary VZV was present in every patient on the day antiviral (acyclovir) treatment was initiated. Pain and skin lesions decreased with antiviral treatment. Corresponding decreases in levels of VZV were also observed and accompanied recovery. Although the level of VZV in shingles patients before the treatment was generally higher than those found in astronauts, lower range of VZV numbers in shingles patients overlapped with astronaut s levels. This suggests a potential risk of shingles to astronauts resulting from reactivation of VZV. In

  6. Antiviral activities of coffee extracts in vitro.

    Science.gov (United States)

    Utsunomiya, Hirotoshi; Ichinose, Masao; Uozaki, Misao; Tsujimoto, Kazuko; Yamasaki, Hisashi; Koyama, A Hajime

    2008-06-01

    Both hot water extracts of coffee grinds and instant coffee solutions inhibited the multiplication of herpes simplex virus type 1, a representative enveloped DNA virus, when they were added to the culture medium of the virus-infected cells at a dose of one fifth the concentration suitable for drinking. The antiherpetic activity was independent of the suppliers (companies) of the coffee grinds and of the locations where the coffee beans were produced. Further characterization revealed that there are two different mechanisms, by which the coffee extracts exert inhibitory activities on the virus infection; (1) a direct inactivation of the infectivity of virus particle (i.e., a virucidal activity) and (2) the inhibition of progeny infectious virus formation at the late stage of viral multiplication in the infected cells. Caffeine, but not quinic acid and chlorogenic acid, inhibited the virus multiplication to some extent, but none of them showed the virucidal activity, suggesting that other component(s) in the coffee extracts must play a role in the observed antiviral activity. In addition, the coffee extracts inhibited the multiplication of poliovirus, a non-enveloped RNA virus, but showed no virucidal effect on this virus.

  7. RNA interference: Antiviral weapon and beyond

    Institute of Scientific and Technical Information of China (English)

    Quan-Chu Wang; Qing-He Nie; Zhi-Hua Feng

    2003-01-01

    RNA interference (RNAi) is a remarkable type of gene regulation based on sequence-specific targeting and degradation of RNA. The term encompasses related pathways found in a broad range of eukaryotic organisms, including fungi, plants, and animals. RNA interference is part of a sophisticated network of interconnected pathways for cellular defense, RNA surveillance, and development and it may become a powerful tool to manipulate gene expression experimentally. RNAi technology is currently being evaluated not only as an extremely powerful instrument for functional genomic analyses, but also as a potentially useful method to develop specific dsRNA based gene-silencing therapeutics.Several laboratories have been interested in using RNAi to control viral infection and many reports in Nature and in Cell show that short interfering (si) RNAs can inhibit infection by HIV-1, polio and hepatitis C viruses in a sequence-specific manner. RNA-based strategies for gene inhibition in mammalian cells have recently been described, which offer the promise of antiviral therapy.

  8. Probiotics as Antiviral Agents in Shrimp Aquaculture

    Directory of Open Access Journals (Sweden)

    Bestha Lakshmi

    2013-01-01

    Full Text Available Shrimp farming is an aquaculture business for the cultivation of marine shrimps or prawns for human consumption and is now considered as a major economic and food production sector as it is an increasingly important source of protein available for human consumption. Intensification of shrimp farming had led to the development of a number of diseases, which resulted in the excessive use of antimicrobial agents, which is finally responsible for many adverse effects. Currently, probiotics are chosen as the best alternatives to these antimicrobial agents and they act as natural immune enhancers, which provoke the disease resistance in shrimp farm. Viral diseases stand as the major constraint causing an enormous loss in the production in shrimp farms. Probiotics besides being beneficial bacteria also possess antiviral activity. Exploitation of these probiotics in treatment and prevention of viral diseases in shrimp aquaculture is a novel and efficient method. This review discusses the benefits of probiotics and their criteria for selection in shrimp aquaculture and their role in immune power enhancement towards viral diseases.

  9. Probiotics as antiviral agents in shrimp aquaculture.

    Science.gov (United States)

    Lakshmi, Bestha; Viswanath, Buddolla; Sai Gopal, D V R

    2013-01-01

    Shrimp farming is an aquaculture business for the cultivation of marine shrimps or prawns for human consumption and is now considered as a major economic and food production sector as it is an increasingly important source of protein available for human consumption. Intensification of shrimp farming had led to the development of a number of diseases, which resulted in the excessive use of antimicrobial agents, which is finally responsible for many adverse effects. Currently, probiotics are chosen as the best alternatives to these antimicrobial agents and they act as natural immune enhancers, which provoke the disease resistance in shrimp farm. Viral diseases stand as the major constraint causing an enormous loss in the production in shrimp farms. Probiotics besides being beneficial bacteria also possess antiviral activity. Exploitation of these probiotics in treatment and prevention of viral diseases in shrimp aquaculture is a novel and efficient method. This review discusses the benefits of probiotics and their criteria for selection in shrimp aquaculture and their role in immune power enhancement towards viral diseases.

  10. Antiviral Warrior-APOBEC3G

    Institute of Scientific and Technical Information of China (English)

    WU Xiao-xia; MA Yi-cai

    2005-01-01

    This paper is to further understand how APOBEC3G can defend the retroviruses and to find new approaches to AIDs (acquired immure deficiency syndrome).The viral infectivity factor (Vif) induces rapid degradation of APOBEC3G by ubiquitination, which is a proteosome-dependent pathway. Precisely speaking, only in the virus-producing cell Vif expression is necessary; in its absence, infection of a subsequent target cell terminates at a postentry step through the action of the human APOBEC3G antiviral mechanism. Vif protein has two domains: one binds to APOBEC3G and the other regulates the degradation of APOBEC3G by a conserved sequence, SLQ (Y/F) LA motif. Recently, the research on Vif has also revealed APOBEC3G is a novel component of innate immune system. In fact, APOBEC3G not only acts in DNA editing to block the replication of retroviruses such as HIV-1, but also is able to defend a wide spectrum of distantly related retroviruses and interferes with HBV through a different mechanism from HIV.

  11. Ribozymes:an anti-viral agent

    Institute of Scientific and Technical Information of China (English)

    Asad U.Khan; Shahper N.Khan

    2008-01-01

    The discovery that RNA can act as an enzyme led Thomas Cech to win the Nobel Prize in Chemistry and led immediately to the next wave of attempts to find an effective RNA-based therapy.The tantalizing idea that RNA enzymes called trans-cleaving ribozymes enables them to act as potential antiviral and powerful tool for functional genomic studies.The efficacy of ribozyme function in a complex intracellular environment is depend-ent on the intracellular fate of the RNA that is being targeted.Recently,ribozymes have been used successfully to inhibit gene expression in a variety of biological systems in vitro and in vivo.Ribozyme has also been used successfully to combat many cases of viral infection,as clinical trial.Despite it needs to be investigated and explored as far as its structural and functional aspects are concern.In view of the significance of ribozyme in modern medicine,we reviewed the recent literature on general approach to control viral infection.

  12. Antiviral activity of lactoferrin towards naked viruses.

    Science.gov (United States)

    Seganti, Lucilla; Di Biase, Assunta Maria; Marchetti, Magda; Pietrantoni, Agostina; Tinari, Antonella; Superti, Fabiana

    2004-06-01

    It is well known that lactoferrin (Lf) is a potent inhibitor towards several enveloped and naked viruses, such as rotavirus, enterovirus and adenovirus. Lf is resistant to tryptic digestion and breast-fed infants excrete high levels of faecal Lf, so that its effect on viruses replicating in the gastrointestinal tract is of great interest. In this report, we analysed the mechanism of the antiviral action of this protein in three viral models which, despite representing different genoma and replication strategies, share the ability to infect the gut. Concerning the mechanism of action against rotavirus, Lf from bovine milk (BLf) possesses a dual role, preventing virus attachment to intestinal cells by binding to viral particles, and inhibiting a post adsorption step. The BLf effect towards poliovirus is due to the interference with an early infection step but, when the BLf molecule is saturated with Zn+2 ions, it is also capable of inhibiting viral replication after the viral adsorption phase. The anti-adenovirus action of BLf takes place on virus attachment to cell membranes through competition for common glycosaminoglycan receptors and a specific interaction with viral structural polypeptides. Taken together, these findings provide further evidence that Lf is an excellent candidate in the search of natural agents against viral enteric diseases, as it mainly acts by hindering adsorption and internalisation into cells through specific binding to cell receptors and/or viral particles.

  13. Perspective of Use of Antiviral Peptides against Influenza Virus

    Directory of Open Access Journals (Sweden)

    Sylvie Skalickova

    2015-10-01

    Full Text Available The threat of a worldwide influenza pandemic has greatly increased over the past decade with the emergence of highly virulent avian influenza strains. The increased frequency of drug-resistant influenza strains against currently available antiviral drugs requires urgent development of new strategies for antiviral therapy, too. The research in the field of therapeutic peptides began to develop extensively in the second half of the 20th century. Since then, the mechanisms of action for several peptides and their antiviral prospect received large attention due to the global threat posed by viruses. Here, we discussed the therapeutic properties of peptides used in influenza treatment. Peptides with antiviral activity against influenza can be divided into three main groups. First, entry blocker peptides such as a Flupep that interact with influenza hemagglutinin, block its binding to host cells and prevent viral fusion. Second, several peptides display virucidal activity, disrupting viral envelopes, e.g., Melittin. Finally, a third set of peptides interacts with the viral polymerase complex and act as viral replication inhibitors such as PB1 derived peptides. Here, we present a review of the current literature describing the antiviral activity, mechanism and future therapeutic potential of these influenza antiviral peptides.

  14. Natural Products as Source of Potential Dengue Antivirals

    Directory of Open Access Journals (Sweden)

    Róbson Ricardo Teixeira

    2014-06-01

    Full Text Available Dengue is a neglected disease responsible for 22,000 deaths each year in areas where it is endemic. To date, there is no clinically approved dengue vaccine or antiviral for human beings, even though there have been great efforts to accomplish these goals. Several approaches have been used in the search for dengue antivirals such as screening of compounds against dengue virus enzymes and structure-based computational discovery. During the last decades, researchers have turned their attention to nature, trying to identify compounds that can be used as dengue antivirals. Nature represents a vast reservoir of substances that can be explored with the aim of discovering new leads that can be either used directly as pharmaceuticals or can serve as lead structures that can be optimized towards the development of new antiviral agents against dengue. In this review we describe an assortment of natural products that have been reported as possessing dengue antiviral activity. The natural products are organized into classes of substances. When appropriate, structure-activity relationships are outlined. The biological assays used to assess antiviral activity are briefly described.

  15. Coronavirus antibodies in African bat species.

    Science.gov (United States)

    Müller, Marcel A; Paweska, Janusz T; Leman, Patricia A; Drosten, Christian; Grywna, Klaus; Kemp, Alan; Braack, Leo; Sonnenberg, Karen; Niedrig, Matthias; Swanepoel, Robert

    2007-09-01

    Asian bats have been identified as potential reservoir hosts of coronaviruses associated with severe acute respiratory syndrome (SARS-CoV). We detected antibody reactive with SARS-CoV antigen in 47 (6.7%) of 705 bat serum specimens comprising 26 species collected in Africa; thus, African bats may harbor agents related to putative group 4 CoV.

  16. Reduction-mediated technetium-99m labeling of monoclonal antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Mather, S.J.; Ellison, D. (St. Bartholomews Hospital, London (England))

    1990-05-01

    A simple and generally applicable method for labeling antibodies with technetium-99m ({sup 99m}Tc) is described. Following reduction of intrinsic disulphide bonds, the antibody is labeled with {sup 99m}Tc in the presence of a weak competing ligand methylene diphosphonate. High labeling efficiencies (greater than 97%), in a final labeling step taking only a few minutes, can be routinely obtained with high in-vitro stability over 24 hr. No effect upon antibody reactivity is seen.

  17. Hepatitis C virus cell-cell transmission and resistance to direct-acting antiviral agents

    DEFF Research Database (Denmark)

    Xiao, Fei; Fofana, Isabel; Heydmann, Laura

    2014-01-01

    Hepatitis C virus (HCV) is transmitted between hepatocytes via classical cell entry but also uses direct cell-cell transfer to infect neighboring hepatocytes. Viral cell-cell transmission has been shown to play an important role in viral persistence allowing evasion from neutralizing antibodies......-targeting entry inhibitors (HTEIs) was highly effective in inhibiting viral dissemination of resistant genotype 2 viruses. Combining HTEIs with DAAs prevented antiviral resistance and led to rapid elimination of the virus in cell culture model. In conclusion, our work provides evidence that cell-cell transmission...... plays an important role in dissemination and maintenance of resistant variants in cell culture models. Blocking virus cell-cell transmission prevents emergence of drug resistance in persistent viral infection including resistance to HCV DAAs....

  18. The Role of Cytokine PF4 in the Antiviral Immune Response of Shrimp

    Science.gov (United States)

    Chen, Yulei; Cao, Jiao; Zhang, Xiaobo

    2016-01-01

    During viral infection in vertebrates, cytokines play important roles in the host defense against the virus. However, the function of cytokines in invertebrates has not been well characterized. In this study, shrimp cytokines involved in viral infection were screened using a cytokine antibody microarray. The results showed that three cytokines, the Fas receptor (Fas), platelet factor 4 (PF4) and interleukin-22 (IL-22), were significantly upregulated in the white spot syndrome virus (WSSV)-challenged shrimp, suggesting that these cytokines played positive regulatory roles in the immune response of shrimp against the virus. Further experiments revealed that PF4 had positive effects on the antiviral immunity of shrimp by enhancing the shrimp phagocytic activity and inhibiting the apoptotic activity of virus-infected hemocytes. Therefore, our study presented a novel mechanism of cytokines in the innate immunity of invertebrates. PMID:27631372

  19. Seroepidemiology of Human Papillomavirus 16 (HPV16) L2 and Generation of L2-Specific Human Chimeric Monoclonal Antibodies

    National Research Council Canada - National Science Library

    Wang, Joshua W; Jagu, Subhashini; Wu, Wai-Hong; Viscidi, Raphael P; Macgregor-Das, Anne; Fogel, Jessica M; Kwak, Kihyuck; Daayana, Sai; Kitchener, Henry; Stern, Peter L; Gravitt, Patti E; Trimble, Cornelia L; Roden, Richard B S

    2015-01-01

    Presently, the seroprevalence of human papillomavirus (HPV) minor capsid antigen L2-reactive antibody is not well understood, and no serologic standard exists for L2-specific neutralizing antibodies...

  20. ANTIBODIES DEFINING RAT ENDOTHELIAL-CELLS - RECA-1, A PAN-ENDOTHELIAL CELL-SPECIFIC MONOCLONAL-ANTIBODY

    NARCIS (Netherlands)

    DUIJVESTIJN, AM; VANGOOR, H; KLATTER, F; MAJOOR, GD; VANBUSSEL, E; VRIESMAN, PJCV

    1992-01-01

    We have been searching for antibodies reactive with rat endothelial cells. Two monoclonal antibodies (mAb), named RECA-1 and RECA-2 were produced and tested in immunoperoxidase staining on frozen sections of various rat tissues. Staining patterns were compared to those obtained with the mAbs OX-2, O

  1. ANTIBODIES DEFINING RAT ENDOTHELIAL-CELLS - RECA-1, A PAN-ENDOTHELIAL CELL-SPECIFIC MONOCLONAL-ANTIBODY

    NARCIS (Netherlands)

    DUIJVESTIJN, AM; VANGOOR, H; KLATTER, F; MAJOOR, GD; VANBUSSEL, E; VRIESMAN, PJCV

    1992-01-01

    We have been searching for antibodies reactive with rat endothelial cells. Two monoclonal antibodies (mAb), named RECA-1 and RECA-2 were produced and tested in immunoperoxidase staining on frozen sections of various rat tissues. Staining patterns were compared to those obtained with the mAbs OX-2, O

  2. An antiviral disulfide compound blocks interaction between arenavirus Z protein and cellular promyelocytic leukemia protein

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, C.C. [Laboratory of Virology, Department of Biological Chemistry, School of Sciences, University of Buenos Aires, 1428 Buenos Aires (Argentina); Topisirovic, I. [Institute de Recherche en Immunologie et en Cancerologie, Universite de Montreal, Montreal, QC, Canada H3T 1J4 (Canada); Djavani, M. [Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, MD 21201 (United States); Borden, K.L.B. [Institute de Recherche en Immunologie et en Cancerologie, Universite de Montreal, Montreal, QC, Canada H3T 1J4 (Canada); Damonte, E.B. [Laboratory of Virology, Department of Biological Chemistry, School of Sciences, University of Buenos Aires, 1428 Buenos Aires (Argentina); Salvato, M.S., E-mail: msalvato@ihv.umaryland.edu [Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, MD 21201 (United States)

    2010-03-19

    The promyelocytic leukemia protein (PML) forms nuclear bodies (NB) that can be redistributed by virus infection. In particular, lymphocytic choriomeningitis virus (LCMV) influences disruption of PML NB through the interaction of PML with the arenaviral Z protein. In a previous report, we have shown that the disulfide compound NSC20625 has antiviral and virucidal properties against arenaviruses, inducing unfolding and oligomerization of Z without affecting cellular RING-containing proteins such as the PML. Here, we further studied the effect of the zinc-finger-reactive disulfide NSC20625 on PML-Z interaction. In HepG2 cells infected with LCMV or transiently transfected with Z protein constructs, treatment with NSC20625 restored PML distribution from a diffuse-cytoplasmic pattern to punctate, discrete NB which appeared identical to NB found in control, uninfected cells. Similar results were obtained in cells transfected with a construct expressing a Z mutant in zinc-binding site 2 of the RING domain, confirming that this Z-PML interaction requires the integrity of only one zinc-binding site. Altogether, these results show that the compound NSC20625 suppressed Z-mediated PML NB disruption and may be used as a tool for designing novel antiviral strategies against arenavirus infection.

  3. [Guideline for interpretation and report of the antibody to hepatitis C virus. Grupo de Desarrollo de la Guía ].

    Science.gov (United States)

    Contreras, Ana M; Ochoa-Jiménez, Rodolfo J; Kershenobich, David; Granados-García, Víctor; Conde-González, Carlos J; Celis, Alfredo; Pérez-Gómez, Héctor R; Ruelas-Hernández, Sara; Romero-Flores, Patricia; Alcántar-Luna, Ernesto; Sierra-García de Quevedo, Julio; Ancona-Pisté, Oscar

    2012-01-01

    Patients with hepatitis C virus (HCV) infection are detected by testing for the presence of antibodies to HCV (Anti-HCV). A positive Anti-HCV test represents a true positive result only in a variable proportion of subjects (35 to 95%). The qualitative interpretation as positive or negative Anti-HCV report is associated with a general lack of understanding regarding the interpretation of results, when more specific testing should be performed, and which tests should be considered for this purpose. Therefore, a substantial variation in supplemental testing practices exists among laboratories and physicians. This guideline was developed on the basis of the best available evidence to classify positive antibody in two (low and high) or three levels (very low, low and high) according to the signal to cutoff (S/CO) ratio: the very low level of the Anti-HCV identifies false-positive results and further diagnostic testing is not necessary. The low antibody level is frequently related with false-positive results and testing with Immunoblot is recommended; only Immunoblot-positive subjects require HCV RNA testing because of a low possibility of being viremic. The high Anti-HCV level is an accurate serological marker for predicting viremia and denotes the need of routine HCV RNA testing in order to efficiently confirm hepatitis C. Cost-effectiveness analysis, based on the Anti-HCV level, recommends the use of the two or three-levels to choose the confirmatory test of positive antibody. This approach can be implemented without increasing test costs because the S/CO ratio is automatically generated in most laboratory analyzers and would provide health care professionals with useful information for counseling and evaluating patients, to eliminate unwarranted notifications in cases of false antibody reactivity, and correctly identifying those Anti-HCV-positive patients who are infected and need antiviral treatment. The written report should include the antibody level (S/CO ratio

  4. The SARS-coronavirus papain-like protease: structure, function and inhibition by designed antiviral compounds.

    Science.gov (United States)

    Báez-Santos, Yahira M; St John, Sarah E; Mesecar, Andrew D

    2015-03-01

    Over 10 years have passed since the deadly human coronavirus that causes severe acute respiratory syndrome (SARS-CoV) emerged from the Guangdong Province of China. Despite the fact that the SARS-CoV pandemic infected over 8500 individuals, claimed over 800 lives and cost billions of dollars in economic loss worldwide, there still are no clinically approved antiviral drugs, vaccines or monoclonal antibody therapies to treat SARS-CoV infections. The recent emergence of the deadly human coronavirus that causes Middle East respiratory syndrome (MERS-CoV) is a sobering reminder that new and deadly coronaviruses can emerge at any time with the potential to become pandemics. Therefore, the continued development of therapeutic and prophylactic countermeasures to potentially deadly coronaviruses is warranted. The coronaviral proteases, papain-like protease (PLpro) and 3C-like protease (3CLpro), are attractive antiviral drug targets because they are essential for coronaviral replication. Although the primary function of PLpro and 3CLpro are to process the viral polyprotein in a coordinated manner, PLpro has the additional function of stripping ubiquitin and ISG15 from host-cell proteins to aid coronaviruses in their evasion of the host innate immune responses. Therefore, targeting PLpro with antiviral drugs may have an advantage in not only inhibiting viral replication but also inhibiting the dysregulation of signaling cascades in infected cells that may lead to cell death in surrounding, uninfected cells. This review provides an up-to-date discussion on the SARS-CoV papain-like protease including a brief overview of the SARS-CoV genome and replication followed by a more in-depth discussion on the structure and catalytic mechanism of SARS-CoV PLpro, the multiple cellular functions of SARS-CoV PLpro, the inhibition of SARS-CoV PLpro by small molecule inhibitors, and the prospect of inhibiting papain-like protease from other coronaviruses. This paper forms part of a series of

  5. ANTI-VIRAL ACTIVITY OF GLYCIRRHETINIC AND GLYCIRRHIZIC ACIDS

    Directory of Open Access Journals (Sweden)

    V. V. Zarubaev

    2016-01-01

    Full Text Available Influenza is a highly contagious human disease. In the course of use of antiviral drugs drug-resistant strains of the virus are formed, resulting in reduced efficiency of the chemotherapy. The review describes the biological activity of glycirrhetinic (GLA and glycirrhizic (GA acids in terms of their use as a therapeutic agent for viral infections. So, these compounds are against a broad spectrum of viruses, including herpes, corona-, alphaand flaviviruses, human immunodeficiency virus, vaccinia virus, poliovirus type I, vesicular stomatitis virus and influenza A virus. These data indicate that anti-viral effect of these compounds is due to several types of activity — direct antiviral effects, effects on cellular proand anti-viral and immunomodulating pathways, in particular by activation of innate immunity system. GA interferes with early steps of the viral reproductive cycle such as virus binding to its receptor, the absorption of the virus by endocytosis or virus decapsidation in the cytoplasm. This is due to the effect of GA-induced reduction of membrane fluidity. Thus, one mechanism for the antiviral activity of GA is that GA molecule increases the rigidity of cellular and viral membranes after incorporation in there. This results in increasing of energy threshold required for the formation of negative curvature at the fusion zones, as well as difficult lateral migration of the virus-receptor complexes. In addition, glycyrrhizin prevents interaction of viral nucleoprotein with cellular protein HMGB1, which is necessary for the viral life cycle. Glycyrrhizin also inhibits the induction of oxidative stress during influenza infection, exhibiting antioxidant properties, which leads to a reduction of virus-induced production of cytokines/chemokines, without affecting the replication of the virus. A wide spectrum of biological activity and effect on various aspects of the viral pathogenesis substantiate the effect of GA and GLA as a component

  6. Antiviral treatment for Bell's palsy (idiopathic facial paralysis

    Directory of Open Access Journals (Sweden)

    Ildiko Gagyor

    Full Text Available ABSTRACTBACKGROUND: Corticosteroids are widely used in the treatment of idiopathic facial paralysis (Bell's palsy, but the effectiveness of additional treatment with an antiviral agent is uncertain. Significant morbidity can be associated with severe cases of Bell's palsy.OBJECTIVES: To assess the effects of antiviral treatments alone or in combination with any other therapy for Bell's palsy.METHODS:Search methods:On 7 October 2014 we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS, DARE, NHS EED, and HTA. We also reviewed the bibliographies of the identified trials and contacted trial authors and known experts in the field and relevant drug companies to identify additional published or unpublished data. We searched clinical trials registries for ongoing studies.Selection criteria:We considered randomised controlled trials or quasi-randomised controlled trials of antivirals with and without corticosteroids versus control therapies for the treatment of Bell's palsy.We excluded trials that had a high risk of bias in several domains.Data collection and analysis:Pairs of authors independently assessed trials for relevance, eligibility, and risk of bias, using standard Cochrane procedures.MAIN RESULTS: Eleven trials, including 2883 participants, met the inclusion criteria and are included in the final analysis. We added four studies to the previous review for this update. Some of the trials were small, and a number were at high or unclear risk of bias. Other trials did not meet current best standards in allocation concealment and blinding. Incomplete recovery:We found no significant benefit from adding antivirals to corticosteroids in comparison with corticosteroids alone for people with Bell's palsy (risk ratio (RR 0.69, 95% confidence interval (CI 0.47 to 1.02, n = 1715. For people with severe Bell's palsy (House Brackmann scores of 5 and 6 or the equivalent in other scales, we found a

  7. [Citomegalovirus reactivation in critical ill intensive care patients].

    Science.gov (United States)

    Carrillo Esper, Raúl

    2011-01-01

    Cytomegalovirus (CMV) is a β herpesvirus and a significant human pathogen. After primary infection establishes life long latency. In immunocompetent individuals cell-mediated host immune responses prevent the development of overt CMV disease. It has increasingly come to be recognized that critically ill patients are at risk for CMV reactivation from the latency. The risk factors associated to CMV reactivation in the critically ill are infection, sepsis, trauma, transfusions, major surgery, prolonged mechanical ventilation, steroids and vasopressors. In the pathogenesis are involved immunodysfunction and imbalance in immunomodulatory mediators principally tumor necrosis factor (TNF) and nuclear factor κB (NF-κB). Several studies have shown an association between CMV reactivation in immunocompetent critically ill patients and poor clinical outcomes. Further studies are warranted to identify subsets of patients who are at risk of developing CMV reactivation and to determine the role of antiviral agents on clinically outcomes in critically ill patients.

  8. Hepatitis C and double-hit B cell lymphoma successfully treated by antiviral therapy.

    Science.gov (United States)

    Galati, Giovanni; Rampa, Lorenzo; Vespasiani-Gentilucci, Umberto; Marino, Mirella; Pisani, Francesco; Cota, Carlo; Guidi, Alessandro; Picardi, Antonio

    2016-10-18

    B cells lymphoma is one of the most challenging extra-hepatic manifestations of hepatitis C virus (HCV). Recently, a new kind of B-cell lymphoma, named double-hit B (DHL), was characterized with an aggressive clinical course whereas a potential association with HCV was not investigated. The new antiviral direct agents (DAAs) against HCV are effective and curative in the majority of HCV infections. We report the first case, to our knowledge, of DHL and HCV-infection successfully treated by new DAAs. According to our experience, a DHL must be suspected in case of HCV-related lymphoma, and an early diagnosis could direct towards a different hematological management because a worse prognosis might be expected. A possible effect of DAAs on DHL regression should be investigated, but eradicating HCV would avoid life-threatening reactivation of viral hepatitis during pharmacological immunosuppression in onco-haematological diseases.

  9. EFFECT OF POLYCLONAL AND MONOCLONAL-ANTIBODIES ON SURFACE-PROPERTIES OF STREPTOCOCCUS-SOBRINUS

    NARCIS (Netherlands)

    VANRAAMSDONK, M; VANDERMEI, HC; DESOET, JJ; BUSSCHER, HJ; DEGRAAFF, J

    1995-01-01

    In this study, the effect of antibody adsorption on physicochemical properties of Streptococcus sobrinus was studied. Bacteria were preincubated with polyclonal antibodies or with OMVU10, a monoclonal antibody (MAb) reactive with S. sobrinus. The zeta potentials and the hydrophobicity as determined

  10. Probiotics stimulate production of natural antibodies in chickens.

    Science.gov (United States)

    Haghighi, Hamid R; Gong, Jianhua; Gyles, Carlton L; Hayes, M Anthony; Zhou, Huaijun; Sanei, Babak; Chambers, James R; Sharif, Shayan

    2006-09-01

    Commensal bacteria in the intestine play an important role in the development of immune response. These bacteria interact with cells of the gut-associated lymphoid tissues (GALT). Among cells of the GALT, B-1 cells are of note. These cells are involved in the production of natural antibodies. In the present study, we determined whether manipulation of the intestinal microbiota by administration of probiotics, which we had previously shown to enhance specific systemic antibody response, could affect the development of natural antibodies in the intestines and sera of chickens. Our findings demonstrate that when 1-day-old chicks were treated with probiotics, serum and intestinal antibodies reactive to tetanus toxoid (TT) and Clostridium perfringens alpha-toxin in addition to intestinal immunoglobulin A (IgA) reactive to bovine serum albumin (BSA) were increased in unimmunized chickens. Moreover, IgG antibodies reactive to TT were increased in the intestines of probiotic-treated chickens compared to those of untreated controls. In serum, IgG and IgM reactive to TT and alpha-toxin were increased in probiotic-treated, unimmunized chickens compared to levels in untreated controls. However, no significant difference in serum levels of IgM or IgG response to BSA was observed. These results are suggestive of the induction of natural antibodies in probiotic-treated, unimmunized chickens. Elucidating the role of these antibodies in maintenance of the chicken immune system homeostasis and immune response to pathogens requires further investigation.

  11. Selection of antibodies from synthetic antibody libraries.

    Science.gov (United States)

    Harel Inbar, Noa; Benhar, Itai

    2012-10-15

    More than 2 dozen years had passed since the field of antibody engineering was established, with the first reports of bacterial [1-3] and mammalian cells [4] expression of recombinant antibody fragments, and in that time a lot of effort was dedicated to the development of efficient technological means, intended to assist in the creation of therapeutic monoclonal antibodies (mAbs). Research focus was given to two intertwined technological aspects: the selection platform and the recombinant antibody repertoires. In accordance with these areas of interest, it is the goal of this chapter to describe the various selection tools and antibody libraries existing, with emphasis on the later, and their applications. This chapter gives a far from exhaustive, subjective "historic account" of the field, describing the selection platforms, the different formats of antibody repertoires and the applications of both for selecting recombinant antibodies. Several excellent books provide detailed protocols for constructing antibody libraries and selecting antibodies from those libraries [5-13]. Such books may guide a newcomer to the field in the fine details of antibody engineering. We would like to offer advice to the novice: although seemingly simple, effective library construction and antibody isolation provide best benefits in the hands of professionals. It is an art as much as it is science.

  12. Mechanisms of virus resistance and antiviral activity of snake venoms

    Directory of Open Access Journals (Sweden)

    JVR Rivero

    2011-01-01

    Full Text Available Viruses depend on cell metabolism for their own propagation. The need to foster an intimate relationship with the host has resulted in the development of various strategies designed to help virus escape from the defense mechanisms present in the host. Over millions of years, the unremitting battle between pathogens and their hosts has led to changes in evolution of the immune system. Snake venoms are biological resources that have antiviral activity, hence substances of significant pharmacological value. The biodiversity in Brazil with respect to snakes is one of the richest on the planet; nevertheless, studies on the antiviral activity of venom from Brazilian snakes are scarce. The antiviral properties of snake venom appear as new promising therapeutic alternative against the defense mechanisms developed by viruses. In the current study, scientific papers published in recent years on the antiviral activity of venom from various species of snakes were reviewed. The objective of this review is to discuss the mechanisms of resistance developed by viruses and the components of snake venoms that present antiviral activity, particularly, enzymes, amino acids, peptides and proteins.

  13. Bioprospecting of Red Sea Sponges for Novel Antiviral Pharmacophores

    KAUST Repository

    O'Rourke, Aubrie

    2015-05-01

    Natural products offer many possibilities for the treatment of disease. More than 70% of the Earth’s surface is ocean, and recent exploration and access has allowed for new additions to this catalog of natural treasures. The Central Red Sea off the coast of Saudi Arabia serves as a newly accessible location, which provides the opportunity to bioprospect marine sponges with the purpose of identifying novel antiviral scaffolds. Antivirals are underrepresented in present day clinical trials, as well as in the academic screens of marine natural product libraries. Here a high-throughput pipeline was initiated by prefacing the antiviral screen with an Image-based High-Content Screening (HCS) technique in order to identify candidates with antiviral potential. Prospective candidates were tested in a biochemical or cell-based assay for the ability to inhibit the NS3 protease of the West Nile Virus (WNV NS protease) as well as replication and reverse transcription of the Human Immunodeficiency Virus 1 (HIV-1). The analytical chemistry techniques of High-Performance Liquid Chromatograpy (HPLC), Liquid Chromatography-Mass Spectrometry (LC-MS), and Nuclear Magnetic Resonance (NMR) where used in order to identify the compounds responsible for the characteristic antiviral activity of the selected sponge fractions. We have identified a 3-alkyl pyridinium from Amphimedon chloros as the causative agent of the observed WNV NS3 protease inhibition in vitro. Additionally, we identified debromohymenialdisine, hymenialdisine, and oroidin from Stylissa carteri as prospective scaffolds capable of HIV-1 inhibition.

  14. Screening for Antiviral Activities of Isolated Compounds from Essential Oils

    Directory of Open Access Journals (Sweden)

    Akram Astani

    2011-01-01

    Full Text Available Essential oil of star anise as well as phenylpropanoids and sesquiterpenes, for example, trans-anethole, eugenol, β-eudesmol, farnesol, β-caryophyllene and β-caryophyllene oxide, which are present in many essential oils, were examined for their antiviral activity against herpes simplex virus type 1 (HSV-1 in vitro. Antiviral activity was analyzed by plaque reduction assays and mode of antiviral action was determined by addition of the drugs to uninfected cells, to the virus prior to infection or to herpesvirus-infected cells. Star anise oil reduced viral infectivity by >99%, phenylpropanoids inhibited HSV infectivity by about 60–80% and sesquiterpenes suppressed herpes virus infection by 40–98%. Both, star anise essential oil and all isolated compounds exhibited anti-HSV-1 activity by direct inactivation of free virus particles in viral suspension assays. All tested drugs interacted in a dose-dependent manner with herpesvirus particles, thereby inactivating viral infectivity. Star anise oil, rich in trans-anethole, revealed a high selectivity index of 160 against HSV, whereas among the isolated compounds only β-caryophyllene displayed a high selectivity index of 140. The presence of β-caryophyllene in many essential oils might contribute strongly to their antiviral ability. These results indicate that phenylpropanoids and sesquiterpenes present in essential oils contribute to their antiviral activity against HSV.

  15. Antiviral Screening of Multiple Compounds against Ebola Virus

    Directory of Open Access Journals (Sweden)

    Stuart D. Dowall

    2016-10-01

    Full Text Available In light of the recent outbreak of Ebola virus (EBOV disease in West Africa, there have been renewed efforts to search for effective antiviral countermeasures. A range of compounds currently available with broad antimicrobial activity have been tested for activity against EBOV. Using live EBOV, eighteen candidate compounds were screened for antiviral activity in vitro. The compounds were selected on a rational basis because their mechanisms of action suggested that they had the potential to disrupt EBOV entry, replication or exit from cells or because they had displayed some antiviral activity against EBOV in previous tests. Nine compounds caused no reduction in viral replication despite cells remaining healthy, so they were excluded from further analysis (zidovudine; didanosine; stavudine; abacavir sulphate; entecavir; JB1a; Aimspro; celgosivir; and castanospermine. A second screen of the remaining compounds and the feasibility of appropriateness for in vivo testing removed six further compounds (ouabain; omeprazole; esomeprazole; Gleevec; D-LANA-14; and Tasigna. The three most promising compounds (17-DMAG; BGB324; and NCK-8 were further screened for in vivo activity in the guinea pig model of EBOV disease. Two of the compounds, BGB324 and NCK-8, showed some effect against lethal infection in vivo at the concentrations tested, which warrants further investigation. Further, these data add to the body of knowledge on the antiviral activities of multiple compounds against EBOV and indicate that the scientific community should invest more effort into the development of novel and specific antiviral compounds to treat Ebola virus disease.

  16. Characterization of methylsulfinylalkyl glucosinolate specific polyclonal antibodies

    DEFF Research Database (Denmark)

    Mirza, Nadia Muhammad Akram; Schulz, Alexander; Halkier, Barbara Ann

    2016-01-01

    Antibodies towards small molecules, like plant specialized metabolites, are valuable tools for developing quantitative and qualitative analytical techniques. Glucosinolates are the specialized metabolites characteristic of the Brassicales order. Here we describe the characterization of polyclonal...... rabbit antibodies raised against the 4-methylsulfinylbutyl glucosinolate, glucoraphanin that is one of the major glucosinolates in the model plant Arabidopsis thaliana (hereafter Arabidopsis). Analysis of the cross-reactivity of the antibodies against a number of glucosinolates demonstrated...... that it was highly selective for methionine-derived aliphatic glucosinolates with a methyl-sulfinyl group in the side chain. Use of crude plant extracts from Arabidopsis mutants with different glucosinolate profiles showed that the antibodies recognized aliphatic glucosinolates in a plant extract and did not cross...

  17. HIGHER ANTI-HEPARAN SULFATE REACTIVITY DURING SYSTEMIC LUPUS-ERYTHEMATOSUS (SLE) DISEASE EXACERBATIONS WITH RENAL MANIFESTATIONS - A LONG-TERM PROSPECTIVE ANALYSIS

    NARCIS (Netherlands)

    KRAMERS, C; TERMAAT, RM; TERBORG, EJ; VANBRUGGEN, MCJ; KALLENBERG, CGM; BERDEN, JHM

    1993-01-01

    Cross-reactive antibodies against heparan sulphate (HS) have been suggested to play a role in initiating renal disease in SLE. Recently, we found that HS-reactivity is mediated by anti-DNA antibodies complexed with DNA and histones. To evaluate the clinical significance of anti-HS reactivity, we stu

  18. Candidate antibody-based therapeutics against HIV-1.

    Science.gov (United States)

    Gong, Rui; Chen, Weizao; Dimitrov, Dimiter S

    2012-06-01

    Antibody-based therapeutics have been successfully used for the treatment of various diseases and as research tools. Several well characterized, broadly neutralizing monoclonal antibodies (bnmAbs) targeting HIV-1 envelope glycoproteins or related host cell surface proteins show sterilizing protection of animals, but they are not effective when used for therapy of an established infection in humans. Recently, a number of novel bnmAbs, engineered antibody domains (eAds), and multifunctional fusion proteins have been reported which exhibit exceptionally potent and broad neutralizing activity against a wide range of HIV-1 isolates from diverse genetic subtypes. eAds could be more effective in vivo than conventional full-size antibodies generated by the human immune system. Because of their small size (12∼15 kD), they can better access sterically restricted epitopes and penetrate densely packed tissue where HIV-1 replicates than the larger full-size antibodies. HIV-1 possesses a number of mechanisms to escape neutralization by full-size antibodies but could be less likely to develop resistance to eAds. Here, we review the in vitro and in vivo antiviral efficacies of existing HIV-1 bnmAbs, summarize the development of eAds and multispecific fusion proteins as novel types of HIV-1 inhibitors, and discuss possible strategies to generate more potent antibody-based candidate therapeutics against HIV-1, including some that could be used to eradicate the virus.

  19. Passive transfer of antiviral antibodies restricts replication of Aleutian mink disease parvovirus in vivo

    DEFF Research Database (Denmark)

    Alexandersen, Søren; Larsen, S; Cohn, A.

    1989-01-01

    When mink kits were infected neonatally with a highly virulent strain of Aleutian disease virus (ADV), 100% of both Aleutian and non-Aleutian genotype mink died of interstitial pneumonia characterized by permissive ADV infection of alveolar type II cells. Treatment of infected kits with either mi...

  20. Passive transfer of antiviral antibodies restricts replication of Aleutian mink disease parvovirus in vivo

    DEFF Research Database (Denmark)

    Alexandersen, Søren; Larsen, S; Cohn, A.;

    1989-01-01

    When mink kits were infected neonatally with a highly virulent strain of Aleutian disease virus (ADV), 100% of both Aleutian and non-Aleutian genotype mink died of interstitial pneumonia characterized by permissive ADV infection of alveolar type II cells. Treatment of infected kits with either mi...

  1. Recovery of an antiviral antibody response following attrition caused by unrelated infection.

    Directory of Open Access Journals (Sweden)

    Dorothy H L Ng

    2014-01-01

    Full Text Available The homeostatic mechanisms that regulate the maintenance of immunological memory to the multiple pathogen encounters over time are unknown. We found that a single malaria episode caused significant dysregulation of pre-established Influenza A virus-specific long-lived plasma cells (LLPCs resulting in the loss of Influenza A virus-specific Abs and increased susceptibility to Influenza A virus re-infection. This loss of LLPCs involved an FcγRIIB-dependent mechanism, leading to their apoptosis. However, given enough time following malaria, the LLPC pool and humoral immunity to Influenza A virus were eventually restored. Supporting a role for continuous conversion of Influenza A virus-specific B into LLPCs in the restoration of Influenza A virus immunity, B cell depletion experiments also demonstrated a similar requirement for the long-term maintenance of serum Influenza A virus-specific Abs in an intact LLPC compartment. These findings show that, in addition to their established role in the anamnestic response to reinfection, the B cell pool continues to be a major contributor to the maintenance of long-term humoral immunity following primary Influenza A virus infection, and to the recovery from attrition following heterologous infection. These data have implications for understanding the longevity of protective efficacy of vaccinations in countries where continuous infections are endemic.

  2. Sudden sensorineural hearing loss: Is antiviral treatment really necessary?

    Science.gov (United States)

    Övet, Gültekin; Alataş, Necat; Kocacan, Fatma Nur; Gürcüoğlu, Sermin Selver; Görgülü, Hakan; Güzelkara, Fatih; Övet, Habibe

    2015-01-01

    It was aimed to investigate the necessity of antiviral agents in the ISSHL treatment. In this study, the patients, diagnosed with sudden hearing loss and admitted in the first 7 days of hearing loss were divided into two groups; a combination therapy was administered to one of the groups, and famciclovir was administered to the other group as an antiviral treatment in addition to the combined therapy. Both groups were compared in terms of levels of recovery. No statistically significant difference was found in the recovery rates between the two groups (p=0.7). In this study, the additional antiviral treatment was found to have no effect on the remission rates in patients with ISSHL treated with combined therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Phytochemistry, cytotoxicity and antiviral activity of Eleusine indica (sambau)

    Science.gov (United States)

    Iberahim, Rashidah; Yaacob, Wan Ahmad; Ibrahim, Nazlina

    2015-09-01

    Goose grass also known as Eleusine indica (EI) is a local medicinal plant that displays antioxidant, antimicrobial and anticancer activities. The present study is to determine the phytochemical constituents, cytotoxicity and antiviral activities for both crude extract and fraction obtained from the plant. The crude extract contained more secondary metabolites compared to the hexane fraction as gauged using standard phytochemical tests. Cytotoxicity screening against Vero cells using MTT assay showed that the CC50 values for crude extract and hexane fraction were 2.07 and 5.62 mg/ml respectively. The antiviral activity towards Herpes Simplex Virus type 1 (HSV-1) was determined using plaque reduction assay. The selective indices (SI = CC50 / EC50) for both methanol extract and hexane fraction were 12.2 and 6.2 respectively. These results demonstrate that the extract prepared from E. indica possesses phytochemical compound that was non cytotoxic to the cell with potential antiviral activity.

  4. Host Cell Factors as Antiviral Targets in Arenavirus Infection

    Directory of Open Access Journals (Sweden)

    Elsa B. Damonte

    2012-09-01

    Full Text Available Among the members of the Arenaviridae family, Lassa virus and Junin virus generate periodic annual outbreaks of severe human hemorrhagic fever (HF in endemic areas of West Africa and Argentina, respectively. Given the human health threat that arenaviruses represent and the lack of a specific and safe chemotherapy, the search for effective antiviral compounds is a continuous demanding effort. Since diverse host cell pathways and enzymes are used by RNA viruses to fulfill their replicative cycle, the targeting of a host process has turned an attractive antiviral approach in the last years for many unrelated virus types. This strategy has the additional benefit to reduce the serious challenge for therapy of RNA viruses to escape from drug effects through selection of resistant variants triggered by their high mutation rate. This article focuses on novel strategies to identify inhibitors for arenavirus therapy, analyzing the potential for antiviral developments of diverse host factors essential for virus infection.

  5. Host cell factors as antiviral targets in arenavirus infection.

    Science.gov (United States)

    Linero, Florencia N; Sepúlveda, Claudia S; Giovannoni, Federico; Castilla, Viviana; García, Cybele C; Scolaro, Luis A; Damonte, Elsa B

    2012-09-01

    Among the members of the Arenaviridae family, Lassa virus and Junin virus generate periodic annual outbreaks of severe human hemorrhagic fever (HF) in endemic areas of West Africa and Argentina, respectively. Given the human health threat that arenaviruses represent and the lack of a specific and safe chemotherapy, the search for effective antiviral compounds is a continuous demanding effort. Since diverse host cell pathways and enzymes are used by RNA viruses to fulfill their replicative cycle, the targeting of a host process has turned an attractive antiviral approach in the last years for many unrelated virus types. This strategy has the additional benefit to reduce the serious challenge for therapy of RNA viruses to escape from drug effects through selection of resistant variants triggered by their high mutation rate. This article focuses on novel strategies to identify inhibitors for arenavirus therapy, analyzing the potential for antiviral developments of diverse host factors essential for virus infection.

  6. The Antiviral Effect of Baicalin on Enterovirus 71 In Vitro

    Directory of Open Access Journals (Sweden)

    Xiang Li

    2015-08-01

    Full Text Available Baicalin is a flavonoid compound extracted from Scutellaria roots that has been reported to possess antibacterial, anti-inflammatory, and antiviral activities. However, the antiviral effect of baicalin on enterovirus 71 (EV71 is still unknown. In this study, we found that baicalin showed inhibitory activity on EV71 infection and was independent of direct virucidal or prophylactic effect and inhibitory viral absorption. The expressions of EV71/3D mRNA and polymerase were significantly blocked by baicalin treatment at early stages of EV71 infection. In addition, baicalin could decrease the expressions of FasL and caspase-3, as well as inhibit the apoptosis of EV71-infected human embryonal rhabdomyosarcoma (RD cells. Altogether, these results indicate that baicalin exhibits potent antiviral effect on EV71 infection, probably through inhibiting EV71/3D polymerase expression and Fas/FasL signaling pathways.

  7. Antiviral properties from plants of the Mediterranean flora.

    Science.gov (United States)

    Sanna, G; Farci, P; Busonera, B; Murgia, G; La Colla, P; Giliberti, G

    2015-01-01

    Natural products are a successful source in drug discovery, playing a significant role in maintaining human health. We investigated the in vitro cytotoxicity and antiviral activity of extracts from 18 traditionally used Mediterranean plants. Noteworthy antiviral activity was found in the extract obtained from the branches of Daphne gnidium L. against human immunodeficiency virus type-1 (EC50 = 0.08 μg/mL) and coxsackievirus B5 (EC50 = 0.10 μg/mL). Other relevant activities were found against BVDV, YFV, Sb-1, RSV and HSV-1. Interestingly, extracts from Artemisia arborescens L. and Rubus ulmifolius Schott, as well as those from D. gnidium L., showed activities against two different viruses. This extensive antiviral screening allowed us to identify attractive activities, offering opportunities to develop lead compounds with a great pharmaceutical potential.

  8. Antiviral defense in shrimp: from innate immunity to viral infection.

    Science.gov (United States)

    Wang, Pei-Hui; Huang, Tianzhi; Zhang, Xiaobo; He, Jian-Guo

    2014-08-01

    The culture of penaeid shrimp is rapidly developing as a major business endeavor worldwide. However, viral diseases have caused huge economic loss in penaeid shrimp culture industries. Knowledge of shrimp innate immunity and antiviral responses has made important progress in recent years, allowing the design of better strategies for the prevention and control of shrimp diseases. In this study, we have updated information on shrimp antiviral immunity and interactions between shrimp hosts and viral pathogens. Current knowledge and recent progress in immune signaling pathways (e.g., Toll/IMD-NF-κB and JAK-STAT signaling pathways), RNAi, phagocytosis, and apoptosis in shrimp antiviral immunity are discussed. The mechanism of viral infection in shrimp hosts and the interactions between viruses and shrimp innate immune systems are also analyzed.

  9. Commensal bacteria calibrate the activation threshold of innate antiviral immunity.

    Science.gov (United States)

    Abt, Michael C; Osborne, Lisa C; Monticelli, Laurel A; Doering, Travis A; Alenghat, Theresa; Sonnenberg, Gregory F; Paley, Michael A; Antenus, Marcelo; Williams, Katie L; Erikson, Jan; Wherry, E John; Artis, David

    2012-07-27

    Signals from commensal bacteria can influence immune cell development and susceptibility to infectious or inflammatory diseases. However, the mechanisms by which commensal bacteria regulate protective immunity after exposure to systemic pathogens remain poorly understood. Here, we demonstrate that antibiotic-treated (ABX) mice exhibit impaired innate and adaptive antiviral immune responses and substantially delayed viral clearance after exposure to systemic LCMV or mucosal influenza virus. Furthermore, ABX mice exhibited severe bronchiole epithelial degeneration and increased host mortality after influenza virus infection. Genome-wide transcriptional profiling of macrophages isolated from ABX mice revealed decreased expression of genes associated with antiviral immunity. Moreover, macrophages from ABX mice exhibited defective responses to type I and type II IFNs and impaired capacity to limit viral replication. Collectively, these data indicate that commensal-derived signals provide tonic immune stimulation that establishes the activation threshold of the innate immune system required for optimal antiviral immunity. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Identification of anti-CD98 antibody mimotopes for inducing antibodies with antitumor activity by mimotope immunization.

    Science.gov (United States)

    Saito, Misa; Kondo, Masahiro; Ohshima, Motohiro; Deguchi, Kazuki; Hayashi, Hideki; Inoue, Kazuyuki; Tsuji, Daiki; Masuko, Takashi; Itoh, Kunihiko

    2014-04-01

    A mimotope is an antibody-epitope-mimicking peptide retrieved from a phage display random peptide library. Immunization with antitumor antibody-derived mimotopes is promising for inducing antitumor immunity in hosts. In this study, we isolated linear and constrained mimotopes from HBJ127, a tumor-suppressing anti-CD98 heavy chain mAb, and determined their abilities for induction of antitumor activity equal to that of the parent antibody. We detected elevated levels of antipeptide responses, but failed to detect reactivity against native CD98-expressing HeLa cells in sera of immunized mice. Phage display panning and selection of mimotope-immunized mouse spleen-derived antibody Fab library showed that HeLa cell-reactive Fabs were successfully retrieved from the library. This finding indicates that native antigen-reactive Fab clones represented an undetectable minor population in mimotope-induced antibody repertoire. Functional and structural analysis of retrieved Fab clones revealed that they were almost identical to the parent antibody. From these results, we confirmed that mimotope immunization was promising for retrieving antitumor antibodies equivalent to the parent antibody, although the co-administration of adjuvant compounds such as T-cell epitope peptides and Toll-like receptor 4 agonist peptides is likely to be necessary for inducing stronger antitumor immunity than mimotope injection alone.

  11. Antiviral drugs for viruses other than human immunodeficiency virus.

    Science.gov (United States)

    Razonable, Raymund R

    2011-10-01

    Most viral diseases, with the exception of those caused by human immunodeficiency virus, are self-limited illnesses that do not require specific antiviral therapy. The currently available antiviral drugs target 3 main groups of viruses: herpes, hepatitis, and influenza viruses. With the exception of the antisense molecule fomivirsen, all antiherpes drugs inhibit viral replication by serving as competitive substrates for viral DNA polymerase. Drugs for the treatment of influenza inhibit the ion channel M(2) protein or the enzyme neuraminidase. Combination therapy with Interferon-α and ribavirin remains the backbone treatment for chronic hepatitis C; the addition of serine protease inhibitors improves the treatment outcome of patients infected with hepatitis C virus genotype 1. Chronic hepatitis B can be treated with interferon or a combination of nucleos(t)ide analogues. Notably, almost all the nucleos(t) ide analogues for the treatment of chronic hepatitis B possess anti-human immunodeficiency virus properties, and they inhibit replication of hepatitis B virus by serving as competitive substrates for its DNA polymerase. Some antiviral drugs possess multiple potential clinical applications, such as ribavirin for the treatment of chronic hepatitis C and respiratory syncytial virus and cidofovir for the treatment of cytomegalovirus and other DNA viruses. Drug resistance is an emerging threat to the clinical utility of antiviral drugs. The major mechanisms for drug resistance are mutations in the viral DNA polymerase gene or in genes that encode for the viral kinases required for the activation of certain drugs such as acyclovir and ganciclovir. Widespread antiviral resistance has limited the clinical utility of M(2) inhibitors for the prevention and treatment of influenza infections. This article provides an overview of clinically available antiviral drugs for the primary care physician, with a special focus on pharmacology, clinical uses, and adverse effects.

  12. Modelling Virus and Antibody Dynamics during Dengue Virus Infection Suggests a Role for Antibody in Virus Clearance.

    Directory of Open Access Journals (Sweden)

    Hannah E Clapham

    2016-05-01

    Full Text Available Dengue is an infection of increasing global importance, yet uncertainty remains regarding critical aspects of its virology, immunology and epidemiology. One unanswered question is how infection is controlled and cleared during a dengue infection. Antibody is thought to play a role, but little past work has examined the kinetics of both virus and antibody during natural infections. We present data on multiple virus and antibody titres measurements recorded sequentially during infection from 53 Vietnamese dengue patients. We fit mechanistic mathematical models of the dynamics of viral replication and the host immune response to these data. These models fit the data well. The model with antibody removing virus fits the data best, but with a role suggested for ADCC or other infected cell clearance mechanisms. Our analysis therefore shows that the observed viral and antibody kinetics are consistent with antibody playing a key role in controlling viral replication. This work gives quantitative insight into the relationship between antibody levels and the efficiency of viral clearance. It will inform the future development of mechanistic models of how vaccines and antivirals might modify the course of natural dengue infection.

  13. Antibodies as predictors of complex autoimmune diseases.

    Science.gov (United States)

    Vojdani, A

    2008-01-01

    Emerging evidence has suggested environmental factors such as infections and xenobiotics and some dietary proteins and peptides in the pathogenesis of many autoimmune diseases. Considering the fact that autoantibodies can often be detected prior to the onset of a disease, in this study an enzyme immunoassay was used for measurement of antibodies against different highly purified antigens or synthetic peptides originating not only from human tissue, but also from cross-reactive epitopes of infectious agents, dietary proteins and xenobiotics. The measurement of antibodies against a panel of antigens allows for identification of patterns or antibody signatures, rather than just one or two markers of autoimmunity, thus establishing the premise for increased sensitivity and specificity of prediction, as well as positive predictive values. This panel of different autoantibodies was applied to 420 patients with different autoimmune diseases, including pernicious anemia, celiac disease, thyroiditis, lupus, rheumatoid arthritis, osteoarthritis, Addison's disease, type 1 diabetes, cardiovascular disease and autoimmunity, which are presented in this article. In all cases, the levels of these antibodies were significantly elevated in patients versus controls. Antibody patterns related to neuroautoimmune disorders, cancer, and patients with somatic hypermutation will be shown in a subsequent article. We believe that this novel 96 antigen-specific autoantibody or predictive antibody screen should be studied for its incorporation into routine medical examinations. Clinicians should be aware that the detection of antibodies should not automatically mean that a patient will definitely become ill, but would rather give a percentage of risk for autoimmune disease over subsequent months or years.

  14. An innate antiviral pathway acting before interferons at epithelial surfaces

    DEFF Research Database (Denmark)

    Iversen, Marie B; Reinert, Line S; Thomsen, Martin K;

    2016-01-01

    Mucosal surfaces are exposed to environmental substances and represent a major portal of entry for microorganisms. The innate immune system is responsible for early defense against infections and it is believed that the interferons (IFNs) constitute the first line of defense against viruses. Here...... we identify an innate antiviral pathway that works at epithelial surfaces before the IFNs. The pathway is activated independently of known innate sensors of viral infections through a mechanism dependent on viral O-linked glycans, which induce CXCR3 chemokines and stimulate antiviral activity...

  15. Antiviral, antifungal and antiprotozoal agents in the cinema.

    Science.gov (United States)

    García-Sánchez, Jose Elias; García-Sánchez, E; Merino Marcos, M L

    2007-03-01

    Among the antimicrobial agents, antibacterials are the most frequently mentioned in cinematographic plots. Nevertheless, it is not uncommon to come across other antiviral agents, especially antiretrovirals and antiprotozoals. We analyzed the presence of antiviral and antifungal agents in different commercial films, both when they were merely mentioned in passing and when they played a major role in the film. This review essentially aims to address the historical portrayal of these agents in film and to list their appearances. The fictional treatments that appear in some films are not addressed.

  16. Antiviral and cytotoxic activities of some Indonesian plants.

    Science.gov (United States)

    Lohézic-Le Dévéhat, F; Bakhtiar, A; Bézivin, C; Amoros, M; Boustie, J

    2002-08-01

    Ten methanolic extracts from eight Indonesian medicinal plants were phytochemically screened and evaluated for antiviral (HSV-1 and Poliovirus) and cytotoxic activities on murine and human cancer lines (3LL, L1210, K562, U251, DU145, MCF-7). Besides Melastoma malabathricum (Melastomataceae), the Indonesian Loranthaceae species among which Elytranthe tubaeflora, E. maingayi, E. globosa and Scurrula ferruginea exhibited attractive antiviral and cytotoxic activities. Piper aduncum (Piperaceae) was found active on Poliovirus. S. ferruginea was selected for further studies because of its activity on the U251 glioblastoma cells.

  17. Kinetics of the avian influenza-specific humoral responses in lung are indicative of local antibody production

    NARCIS (Netherlands)

    Geus, de E.D.; Rebel, J.M.J.; Vervelde, L.

    2012-01-01

    The role and kinetics of respiratory immunoglobulins in AIV infection has not been investigated. In this study we determined the numbers of both total antibody secreting cells (ASC) and virus-specific ASC in lung, spleen, blood and bone marrow (BM) following low-pathogenic AIV infection. Antiviral h

  18. In vitro neutralisation of rotavirus infection by two broadly specific recombinant monovalent llama-derived antibody fragments

    NARCIS (Netherlands)

    F. Aladin (Farah); A.W.C. Einerhand (Sandra); J. Bouma (Janneke); S. Bezemer (Sandra); P. Hermans (Pim); D. Wolvers (Danielle); K. Bellamy (Kate); L.G.J. Frenken (Leon); J. Gray (Jim); M. Iturriza-Gómara (Miren)

    2012-01-01

    textabstractRotavirus is the main cause of viral gastroenteritis in young children. Therefore, the development of inexpensive antiviral products for the prevention and/or treatment of rotavirus disease remains a priority. Previously we have shown that a recombinant monovalent antibody fragment (refe

  19. Antiviral therapy for prevention of hepatocellular carcinoma in chronic hepatitis C

    DEFF Research Database (Denmark)

    Kimer, Nina; Dahl, Emilie Kristine; Gluud, Lise Lotte;

    2012-01-01

    To determine whether antiviral therapy reduces the risk of developing hepatocellular carcinoma (HCC) in chronic hepatitis C.......To determine whether antiviral therapy reduces the risk of developing hepatocellular carcinoma (HCC) in chronic hepatitis C....

  20. DMPD: The interferon in TLR signaling: more than just antiviral. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 14552837 The interferon in TLR signaling: more than just antiviral. Hertzog PJ, O'N...on in TLR signaling: more than just antiviral. PubmedID 14552837 Title The interferon in TLR signaling: more than just anti

  1. Characterization and evaluation of monoclonal antibodies developed for typing influenza A and influenza B viruses.

    OpenAIRE

    Walls, H H; Harmon, M W; Slagle, J J; Stocksdale, C; Kendal, A P

    1986-01-01

    Monoclonal antibodies that are broadly reactive with influenza A or influenza B viruses were produced as stable reagents for typing influenza viruses. Monoclonal antibodies to influenza A were specific for either matrix protein or nucleoprotein. The antibodies to influenza B were specific for nucleoprotein or hemagglutinin protein. In an enzyme immunoassay procedure, influenza A antibodies detected H1N1, H2N2, and H3N2 influenza A virus strains collected between 1934 and 1984. Each of the inf...

  2. Anti-carbamylated Protein Antibody Levels Correlate with Anti-Sa (Citrullinated Vimentin) Antibody Levels in Rheumatoid Arthritis.

    Science.gov (United States)

    Challener, Gregory J; Jones, Jonathan D; Pelzek, Adam J; Hamilton, B JoNell; Boire, Gilles; de Brum-Fernandes, Artur José; Masetto, Ariel; Carrier, Nathalie; Ménard, Henri A; Silverman, Gregg J; Rigby, William F C

    2016-02-01

    The presence of anticitrullinated protein antibodies (ACPA) in rheumatoid arthritis (RA) indicates a breach in immune tolerance. Recent studies indicate that this breach extends to homocitrullination of lysines with the formation of anti-carbamylated protein (anti-CarP) antibodies. We analyzed the clinical and serologic relationships of anti-CarP in 2 RA cohorts. Circulating levels of immunoglobulin G anti-CarP antibodies were determined by ELISA in established (Dartmouth-Hitchcock Medical Center) and early (Sherbrooke University Hospital Center) cohorts and evaluated for anticyclic citrullinated peptide antibodies (anti-CCP), specific ACPA, and rheumatoid factor (RF) levels using the Student t test and correlation analysis. We identified elevated anti-CarP antibodies titers in 47.0% of seropositive patients (Dartmouth, n = 164), with relationships to anti-CCP (p elevated anti-CarP antibodies; titers correlated to anti-CCP (p = 0.01) but not IgM-RF (p = 0.09). A strong correlation with anti-Sa was observed: 47.9% anti-Sa+ patients were anti-CarP antibodies+ versus only 25.4% anti-Sa- in the Sherbrooke cohort (p = 0.0002), and 62.6% anti-Sa+ patients versus 26.9% anti-Sa- were anti-CarP antibodies+ in Dartmouth (p anti-CarP antibody positivity. We also describe a surprising and unexpected association of anti-CarP with anti-Sa antibodies that could not be explained by cross-reactivity. Further, considerable heterogeneity exists between anti-CarP reactivity and other citrullinated peptide reactivity, raising the question of how the pathogenesis of antibody responses for carbamylated proteins and citrullinated proteins may be linked in vivo.

  3. Flu Resistance to Antiviral Drug in North Carolina

    Centers for Disease Control (CDC) Podcasts

    2011-12-19

    Dr. Katrina Sleeman, Associate Service Fellow at CDC, discusses resistance to an antiviral flu drug in North Carolina.  Created: 12/19/2011 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 12/19/2011.

  4. Antiviral effects of green tea ( Camellia sinensis ) against pathogenic ...

    African Journals Online (AJOL)

    Log in or Register to get access to full text downloads. ... Materials and Methods: We performed a search using the key words “green tea” AND “antiviral” covering the last 10 years. ... Conclusion: A detailed information on the antiviral activity of green tea in a number of different viruses show a promising future as a popular ...

  5. Phytochemical, antioxidant, antiviral and cytotoxic evaluation of Opuntia dillenii flowers

    Directory of Open Access Journals (Sweden)

    Arthanari Saravana Kumar

    2014-08-01

    Full Text Available Opuntia dillenii used in Asian traditional medicine especially in China. We here report on the investigation of the phytochemical content, antioxidant, cytotoxicity and antiviral activity of methanolic extract of O. dillenii flowers. The antioxidant activity was measured with the DPPH, hydrogen peroxide and hydroxyl radicals scavenging method. In the antiviral and cytotoxic assay we used different viruses in different cell lines. In antioxidant assay, the DPPH assay exhibited potent antioxidant abilities with IC50 of 58.7 µg/mL. In antiviral assay, the extract possess strongest antiviral activity against herpes simplex 1(EC50= 25 µg/mL and 2 (EC50= 20 µg/mL, vaccinia (EC50= 100 µg/mL and moderate activity for remaining viruses (EC50= >100 µg/mL. The cytotoxicity effect was evaluated using MTT assay and the results revealed that the extracts exhibited cytotoxicity above the range of 100 µg/mL. Our present reports confirmed that the O. dillenii could be a potential antioxidant and antimicrobial agent in near future.

  6. Evaluation of antiseptic