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Sample records for flavivirus antibody naive

  1. Antibody-based assay discriminates Zika virus infection from other flaviviruses.

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    Balmaseda, Angel; Stettler, Karin; Medialdea-Carrera, Raquel; Collado, Damaris; Jin, Xia; Zambrana, José Victor; Jaconi, Stefano; Cameroni, Elisabetta; Saborio, Saira; Rovida, Francesca; Percivalle, Elena; Ijaz, Samreen; Dicks, Steve; Ushiro-Lumb, Ines; Barzon, Luisa; Siqueira, Patricia; Brown, David W G; Baldanti, Fausto; Tedder, Richard; Zambon, Maria; de Filippis, A M Bispo; Harris, Eva; Corti, Davide

    2017-08-01

    Zika virus (ZIKV) is a mosquito-borne flavivirus that emerged recently as a global health threat, causing a pandemic in the Americas. ZIKV infection mostly causes mild disease, but is linked to devastating congenital birth defects and Guillain-Barré syndrome in adults. The high level of cross-reactivity among flaviviruses and their cocirculation has complicated serological approaches to differentially detect ZIKV and dengue virus (DENV) infections, accentuating the urgent need for a specific and sensitive serological test. We previously generated a ZIKV nonstructural protein 1 (NS1)-specific human monoclonal antibody, which we used to develop an NS1-based competition ELISA. Well-characterized samples from RT-PCR-confirmed patients with Zika and individuals exposed to other flavivirus infections or vaccination were used in a comprehensive analysis to determine the sensitivity and specificity of the NS1 blockade-of-binding (BOB) assay, which was established in laboratories in five countries (Nicaragua, Brazil, Italy, United Kingdom, and Switzerland). Of 158 sera/plasma from RT-PCR-confirmed ZIKV infections, 145 (91.8%) yielded greater than 50% inhibition. Of 171 patients with primary or secondary DENV infections, 152 (88.9%) scored negative. When the control group was extended to patients infected by other flaviviruses, other viruses, or healthy donors ( n = 540), the specificity was 95.9%. We also analyzed longitudinal samples from DENV-immune and DENV-naive ZIKV infections and found inhibition was achieved within 10 d postonset of illness and maintained over time. Thus, the Zika NS1 BOB assay is sensitive, specific, robust, simple, low-cost, and accessible, and can detect recent and past ZIKV infections for surveillance, seroprevalence studies, and intervention trials.

  2. In a randomized trial, the live attenuated tetravalent dengue vaccine TV003 is well-tolerated and highly immunogenic in subjects with flavivirus exposure prior to vaccination.

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    Stephen S Whitehead

    2017-05-01

    Full Text Available Infection caused by the four serotypes of dengue virus (DENV-1-4 is a leading cause of mosquito-borne disease. Clinically-severe dengue disease is more common when secondary dengue infection occurs following prior infection with a heterologous dengue serotype. Other flaviviruses such as yellow fever virus, Japanese encephalitis virus, and Zika virus, can also elicit antibodies which are cross-reactive to DENV. As candidate dengue vaccines become available in endemic settings and for individuals who have received other flavivirus vaccines, it is important to examine vaccine safety and immunogenicity in these flavivirus-experienced populations. We performed a randomized, controlled trial of the National Institutes of Health live attenuated tetravalent dengue vaccine candidate (TV003 in fifty-eight individuals with prior exposure to flavivirus infection or vaccine. As in prior studies of this vaccine in flavivirus-naive volunteers, flavivirus-experienced subjects received two doses of vaccine six months apart and were followed closely for clinical events, laboratory changes, viremia, and neutralizing antibody titers. TV003 was well tolerated with few adverse events other than rash, which was predominately mild. Following one dose, 87% of vaccinees had an antibody response to all four serotypes (tetravalent response, suggesting a robust immune response. In addition, 76% of vaccinees were viremic; mean peak titers ranged from 0.68–1.1 log10 PFU/mL and did not differ by serotype. The second dose of TV003 was not associated with viremia, rash, or a sustained boost in antibody titers indicating that a single dose of the vaccine is likely sufficient to prevent viral replication and thus protect against disease. In comparison to the viremia and neutralizing antibody response elicited by TV003 in flavivirus-naïve subjects from prior studies, we found that subjects who were flavivirus-exposed prior to vaccination exhibited slightly higher DENV-3 viremia

  3. Natural exposure of horses to mosquito-borne flaviviruses in south-east Queensland, Australia.

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    Prow, Natalie A; Tan, Cindy S E; Wang, Wenqi; Hobson-Peters, Jody; Kidd, Lisa; Barton, Anita; Wright, John; Hall, Roy A; Bielefeldt-Ohmann, Helle

    2013-09-17

    In 2011 an unprecedented epidemic of equine encephalitis occurred in south-eastern (SE) Australia following heavy rainfall and severe flooding in the preceding 2-4 months. Less than 6% of the documented cases occurred in Queensland, prompting the question of pre-existing immunity in Queensland horses. A small-scale serological survey was conducted on horses residing in one of the severely flood-affected areas of SE-Queensland. Using a flavivirus-specific blocking-ELISA we found that 63% (39/62) of horses older than 3 years were positive for flavivirus antibodies, and of these 18% (7/38) had neutralizing antibodies to Murray Valley encephalitis virus (MVEV), Kunjin virus (WNV(KUN)) and/or Alfuy virus (ALFV). The remainder had serum-neutralizing antibodies to viruses in the Kokobera virus (KOKV) complex or antibodies to unknown/untested flaviviruses. Amongst eight yearlings one presented with clinical MVEV-encephalomyelitis, while another, clinically normal, had MVEV-neutralizing antibodies. The remaining six yearlings were flavivirus antibody negative. Of 19 foals born between August and November 2011 all were flavivirus antibody negative in January 2012. This suggests that horses in the area acquire over time active immunity to a range of flaviviruses. Nevertheless, the relatively infrequent seropositivity to MVEV, WNV(KUN) and ALFV (15%) suggests that factors other than pre-existing immunity may have contributed to the low incidence of arboviral disease in SE-Queensland horses during the 2011 epidemic.

  4. Thermodynamic Mechanism for the Evasion of Antibody Neutralization in Flaviviruses

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    2015-01-01

    Mutations in the epitopes of antigenic proteins can confer viral resistance to antibody-mediated neutralization. However, the fundamental properties that characterize epitope residues and how mutations affect antibody binding to alter virus susceptibility to neutralization remain largely unknown. To address these questions, we used an ensemble-based algorithm to characterize the effects of mutations on the thermodynamics of protein conformational fluctuations. We applied this method to the envelope protein domain III (ED3) of two medically important flaviviruses: West Nile and dengue 2. We determined an intimate relationship between the susceptibility of a residue to thermodynamic perturbations and epitope location. This relationship allows the successful identification of the primary epitopes in each ED3, despite their high sequence and structural similarity. Mutations that allow the ED3 to evade detection by the antibody either increase or decrease conformational fluctuations of the epitopes through local effects or long-range interactions. Spatially distant interactions originate in the redistribution of conformations of the ED3 ensembles, not through a mechanically connected array of contiguous amino acids. These results reconcile previous observations of evasion of neutralization by mutations at a distance from the epitopes. Finally, we established a quantitative correlation between subtle changes in the conformational fluctuations of the epitope and large defects in antibody binding affinity. This correlation suggests that mutations that allow viral growth, while reducing neutralization, do not generate significant structural changes and underscores the importance of protein fluctuations and long-range interactions in the mechanism of antibody-mediated neutralization resistance. PMID:24950171

  5. Flaviviruses in Europe: Complex Circulation Patterns and Their Consequences for the Diagnosis and Control of West Nile Disease

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    Elsa Jourdain

    2013-11-01

    Full Text Available In Europe, many flaviviruses are endemic (West Nile, Usutu, tick-borne encephalitis viruses or occasionally imported (dengue, yellow fever viruses. Due to the temporal and geographical co-circulation of flaviviruses in Europe, flavivirus differentiation by diagnostic tests is crucial in the adaptation of surveillance and control efforts. Serological diagnosis of flavivirus infections is complicated by the antigenic similarities among the Flavivirus genus. Indeed, most flavivirus antibodies are directed against the highly immunogenic envelope protein, which contains both flavivirus cross-reactive and virus-specific epitopes. Serological assay results should thus be interpreted with care and confirmed by comparative neutralization tests using a panel of viruses known to circulate in Europe. However, antibody cross-reactivity could be advantageous in efforts to control emerging flaviviruses because it ensures partial cross-protection. In contrast, it might also facilitate subsequent diseases, through a phenomenon called antibody-dependent enhancement mainly described for dengue virus infections. Here, we review the serological methods commonly used in WNV diagnosis and surveillance in Europe. By examining past and current epidemiological situations in different European countries, we present the challenges involved in interpreting flavivirus serological tests and setting up appropriate surveillance programs; we also address the consequences of flavivirus circulation and vaccination for host immunity.

  6. Neutralizing antibodies against flaviviruses, Babanki virus, and Rift Valley fever virus in Ugandan bats.

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    Kading, Rebekah C; Kityo, Robert M; Mossel, Eric C; Borland, Erin M; Nakayiki, Teddie; Nalikka, Betty; Nyakarahuka, Luke; Ledermann, Jeremy P; Panella, Nicholas A; Gilbert, Amy T; Crabtree, Mary B; Peterhans, Julian Kerbis; Towner, Jonathan S; Amman, Brian R; Sealy, Tara K; Nichol, Stuart T; Powers, Ann M; Lutwama, Julius J; Miller, Barry R

    2018-01-01

    Introduction: A number of arboviruses have previously been isolated from naturally-infected East African bats, however the role of bats in arbovirus maintenance is poorly understood. The aim of this study was to investigate the exposure history of Ugandan bats to a panel of arboviruses. Materials and methods: Insectivorous and fruit bats were captured from multiple locations throughout Uganda during 2009 and 2011-2013. All serum samples were tested for neutralizing antibodies against West Nile virus (WNV), yellow fever virus (YFV), dengue 2 virus (DENV-2), Zika virus (ZIKV), Babanki virus (BBKV), and Rift Valley fever virus (RVFV) by plaque reduction neutralization test (PRNT). Sera from up to 626 bats were screened for antibodies against each virus. Results and Discussion:  Key findings include the presence of neutralizing antibodies against RVFV in 5/52 (9.6%) of little epauletted fruit bats ( Epomophorus labiatus ) captured from Kawuku and 3/54 (5.6%) Egyptian rousette bats from Kasokero cave. Antibodies reactive to flaviviruses were widespread across bat taxa and sampling locations. Conclusion: The data presented demonstrate the widespread exposure of bats in Uganda to arboviruses, and highlight particular virus-bat associations that warrant further investigation.

  7. Screening test for neutralizing antibodies against yellow fever virus, based on a flavivirus pseudotype.

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    Séverine Mercier-Delarue

    Full Text Available Given the possibility of yellow fever virus reintroduction in epidemiologically receptive geographic areas, the risk of vaccine supply disruption is a serious issue. New strategies to reduce the doses of injected vaccines should be evaluated very carefully in terms of immunogenicity. The plaque reduction test for the determination of neutralizing antibodies (PRNT is particularly time-consuming and requires the use of a confinement laboratory. We have developed a new test based on the use of a non-infectious pseudovirus (WN/YF17D. The presence of a reporter gene allows sensitive determination of neutralizing antibodies by flow cytometry. This WN/YF17D test was as sensitive as PRNT for the follow-up of yellow fever vaccinees. Both tests lacked specificity with sera from patients hospitalized for acute Dengue virus infection. Conversely, both assays were strictly negative in adults never exposed to flavivirus infection or vaccination, and in patients sampled some time after acute Dengue infection. This WN/YF17D test will be particularly useful for large epidemiological studies and for screening for neutralizing antibodies against yellow fever virus.

  8. Stereophysicochemical variability plots highlight conserved antigenic areas in Flaviviruses

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    Zhou Bin

    2005-04-01

    Full Text Available Abstract Background Flaviviruses, which include Dengue (DV and West Nile (WN, mutate in response to immune system pressure. Identifying escape mutants, variant progeny that replicate in the presence of neutralizing antibodies, is a common way to identify functionally important residues of viral proteins. However, the mutations typically occur at variable positions on the viral surface that are not essential for viral replication. Methods are needed to determine the true targets of the neutralizing antibodies. Results Stereophysicochemical variability plots (SVPs, 3-D images of protein structures colored according to variability, as determined by our PCPMer program, were used to visualize residues conserved in their physical chemical properties (PCPs near escape mutant positions. The analysis showed 1 that escape mutations in the flavivirus envelope protein are variable residues by our criteria and 2 two escape mutants found at the same position in many flaviviruses sit above clusters of conserved residues from different regions of the linear sequence. Conservation patterns in T-cell epitopes in the NS3- protease suggest a similar mechanism of immune system evasion. Conclusion The SVPs add another dimension to structurally defining the binding sites of neutralizing antibodies. They provide a useful aid for determining antigenically important regions and designing vaccines.

  9. Detection of the mosquito-borne flaviviruses, West Nile, Dengue, Saint Louis Encephalitis, Ilheus, Bussuquara, and Yellow Fever in free-ranging black howlers (Alouatta caraya of Northeastern Argentina.

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    María A Morales

    2017-02-01

    Full Text Available Several medically important mosquito-borne flaviviruses have been detected in Argentina in recent years: Dengue (DENV, St. Louis encephalitis (SLEV, West Nile (WNV and Yellow Fever (YFV viruses. Evidence of Bussuquara virus (BSQV and Ilheus virus (ILHV activity were found, but they have not been associated with human disease. Non-human primates can act as important hosts in the natural cycle of flaviviruses and serological studies can lead to improved understanding of virus circulation dynamics and host susceptibility. From July-August 2010, we conducted serological and molecular surveys in free-ranging black howlers (Alouatta caraya captured in northeastern Argentina. We used 90% plaque-reduction neutralization tests (PRNT90 to analyze 108 serum samples for antibodies to WNV, SLEV, YFV, DENV (serotypes 1and 3, ILHV, and BSQV. Virus genome detection was performed using generic reverse transcription (RT-nested PCR to identify flaviviruses in 51 antibody-negative animals. Seventy animals had antibodies for one or more flaviviruses for a total antibody prevalence of 64.8% (70/108. Monotypic (13/70, 19% and heterotypic (27/70, 39% patterns were differentiated. Specific neutralizing antibodies against WNV, SLEV, DENV-1, DENV-3, ILHV, and BSQV were found. Unexpectedly, the highest flavivirus antibody prevalence detected was to WNV with 9 (8.33% monotypic responses. All samples tested by (RT-nested PCR were negative for viral genome. This is the first detection of WNV-specific antibodies in black howlers from Argentina and the first report in free-ranging non-human primates from Latin-American countries. Given that no animals had specific neutralizing antibodies to YFV, our results suggest that the study population remains susceptible to YFV. Monitoring of these agents should be strengthened to detect the establishment of sylvatic cycles of flaviviruses in America and evaluate risks to wildlife and human health.

  10. Production and characterization of vaccines based on flaviviruses defective in replication

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    Mason, Peter W.; Shustov, Alexandr V.; Frolov, Ilya

    2006-01-01

    To develop new vaccine candidates for flavivirus infections, we have engineered two flaviviruses, yellow fever virus (YFV) and West Nile virus (WNV), that are deficient in replication. These defective pseudoinfectious viruses (PIVs) lack a functional copy of the capsid (C) gene in their genomes and are incapable of causing spreading infection upon infection of cells both in vivo and in vitro. However, they produce extracellular E protein in form of secreted subviral particles (SVPs) that are known to be an effective immunogen. PIVs can be efficiently propagated in trans-complementing cell lines making high levels of C or all three viral structural proteins. PIVs derived from YFV and WNV, demonstrated very high safety and immunization produced high levels of neutralizing antibodies and protective immune response. Such defective flaviviruses can be produced in large scale under low biocontainment conditions and should be useful for diagnostic or vaccine applications

  11. West Nile Flavivirus Polioencephalomyelitis in a harbor seal (Phoca vitulina).

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    Del Piero, F; Stremme, D W; Habecker, P L; Cantile, C

    2006-01-01

    A 12-year-old male harbor seal presented with progressive signs of neurologic dysfunction including head tremors, muzzle twitching, clonic spasms, and weakness. Lesions included polioencephalomyelitis with glial nodules, spheroids, neuronophagia, ring hemorrhages, and a few neutrophils. Neurons, fibers, and glial nodules were multifocally colonized with intracytoplasmic West Nile flavivirus antigens that were demonstrated using indirect immunohistochemical analysis. Flavivirus on cultured cells also was isolated and was identified by use of monoclonal antibodies and reverse transcriptase-polymerase chain reaction analysis. Clinical signs of disease and lesion morphology and distribution were similar to those of equine West Nile virus infection. Similar to horses, alpacas, humans, dogs, and reptiles, seals can be dead-end hosts of West Nile virus.

  12. Flavivirus-Mosquito Interactions

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    Yan-Jang S. Huang

    2014-11-01

    Full Text Available The Flavivirus genus is in the family Flaviviridae and is comprised of more than 70 viruses. These viruses have a broad geographic range, circulating on every continent except Antarctica. Mosquito-borne flaviviruses, such as yellow fever virus, dengue virus serotypes 1–4, Japanese encephalitis virus, and West Nile virus are responsible for significant human morbidity and mortality in affected regions. This review focuses on what is known about flavivirus-mosquito interactions and presents key data collected from the field and laboratory-based molecular and ultrastructural evaluations.

  13. Construction and characterization of recombinant flaviviruses bearing insertions between E and NS1 genes

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    Kubelka Claire F

    2007-10-01

    Full Text Available Abstract Background The yellow fever virus, a member of the genus Flavivirus, is an arthropod-borne pathogen causing severe disease in humans. The attenuated yellow fever 17D virus strain has been used for human vaccination for 70 years and has several characteristics that are desirable for the development of new, live attenuated vaccines. We described here a methodology to construct a viable, and immunogenic recombinant yellow fever 17D virus expressing a green fluorescent protein variant (EGFP. This approach took into account the presence of functional motifs and amino acid sequence conservation flanking the E and NS1 intergenic region to duplicate and fuse them to the exogenous gene and thereby allow the correct processing of the viral polyprotein precursor. Results YF 17D EGFP recombinant virus was grew in Vero cells and reached a peak titer of approximately 6.45 ± 0.4 log10 PFU/mL at 96 hours post-infection. Immunoprecipitation and confocal laser scanning microscopy demonstrated the expression of the EGFP, which was retained in the endoplasmic reticulum and not secreted from infected cells. The association with the ER compartment did not interfere with YF assembly, since the recombinant virus was fully competent to replicate and exit the cell. This virus was genetically stable up to the tenth serial passage in Vero cells. The recombinant virus was capable to elicit a neutralizing antibody response to YF and antibodies to EGFP as evidenced by an ELISA test. The applicability of this cloning strategy to clone gene foreign sequences in other flavivirus genomes was demonstrated by the construction of a chimeric recombinant YF 17D/DEN4 virus. Conclusion This system is likely to be useful for a broader live attenuated YF 17D virus-based vaccine development for human diseases. Moreover, insertion of foreign genes into the flavivirus genome may also allow in vivo studies on flavivirus cell and tissue tropism as well as cellular processes related

  14. Flavivirus Entry Receptors: An Update

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    Manuel Perera-Lecoin

    2013-12-01

    Full Text Available Flaviviruses enter host cells by endocytosis initiated when the virus particles interact with cell surface receptors. The current model suggests that flaviviruses use at least two different sets of molecules for infectious entry: attachment factors that concentrate and/or recruit viruses on the cell surface and primary receptor(s that bind to virions and direct them to the endocytic pathway. Here, we present the currently available knowledge regarding the flavivirus receptors described so far with specific attention to C-type lectin receptors and the phosphatidylserine receptors, T-cell immunoglobulin and mucin domain (TIM and TYRO3, AXL and MER (TAM. Their role in flavivirus attachment and entry as well as their implication in the virus biology will be discussed in depth.

  15. Flavivirus RNAi suppression: decoding non-coding RNA.

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    Pijlman, Gorben P

    2014-08-01

    Flaviviruses are important human pathogens that are transmitted by invertebrate vectors, mostly mosquitoes and ticks. During replication in their vector, flaviviruses are subject to a potent innate immune response known as antiviral RNA interference (RNAi). This defense mechanism is associated with the production of small interfering (si)RNA that lead to degradation of viral RNA. To what extent flaviviruses would benefit from counteracting antiviral RNAi is subject of debate. Here, the experimental evidence to suggest the existence of flavivirus RNAi suppressors is discussed. I will highlight the putative role of non-coding, subgenomic flavivirus RNA in suppression of RNAi in insect and mammalian cells. Novel insights from ongoing research will reveal how arthropod-borne viruses modulate innate immunity including antiviral RNAi. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Biochemistry and Molecular Biology of Flaviviruses.

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    Barrows, Nicholas J; Campos, Rafael K; Liao, Kuo-Chieh; Prasanth, K Reddisiva; Soto-Acosta, Ruben; Yeh, Shih-Chia; Schott-Lerner, Geraldine; Pompon, Julien; Sessions, October M; Bradrick, Shelton S; Garcia-Blanco, Mariano A

    2018-04-25

    Flaviviruses, such as dengue, Japanese encephalitis, tick-borne encephalitis, West Nile, yellow fever, and Zika viruses, are critically important human pathogens that sicken a staggeringly high number of humans every year. Most of these pathogens are transmitted by mosquitos, and not surprisingly, as the earth warms and human populations grow and move, their geographic reach is increasing. Flaviviruses are simple RNA-protein machines that carry out protein synthesis, genome replication, and virion packaging in close association with cellular lipid membranes. In this review, we examine the molecular biology of flaviviruses touching on the structure and function of viral components and how these interact with host factors. The latter are functionally divided into pro-viral and antiviral factors, both of which, not surprisingly, include many RNA binding proteins. In the interface between the virus and the hosts we highlight the role of a noncoding RNA produced by flaviviruses to impair antiviral host immune responses. Throughout the review, we highlight areas of intense investigation, or a need for it, and potential targets and tools to consider in the important battle against pathogenic flaviviruses.

  17. Identification of a Flavivirus Sequence in a Marine Arthropod.

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    Michael J Conway

    Full Text Available Phylogenetic analysis has yet to uncover the early origins of flaviviruses. In this study, I mined a database of expressed sequence tags in order to discover novel flavivirus sequences. Flavivirus sequences were identified in a pool of mRNA extracted from the sea spider Endeis spinosa (Pycnogonida, Pantopoda. Reconstruction of the translated sequences and BLAST analysis matched the sequence to the flavivirus NS5 gene. Additional sequences corresponding to envelope and the NS5 MTase domain were also identified. Phylogenetic analysis of homologous NS5 sequences revealed that Endeis spinosa NS5 (ESNS5 is likely related to classical insect-specific flaviviruses. It is unclear if ESNS5 represents genetic material from an active viral infection or an integrated viral genome. These data raise the possibility that classical insect-specific flaviviruses and perhaps medically relevant flaviviruses, evolved from progenitors that infected marine arthropods.

  18. Identification of diagnostic peptide regions that distinguish Zika virus from related mosquito-borne Flaviviruses.

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    Alexandra J Lee

    Full Text Available Zika virus (ZIKV is a member of the Flavivirus genus of positive-sense single-stranded RNA viruses, which includes Dengue, West Nile, Yellow Fever, and other mosquito-borne arboviruses. Infection by ZIKV can be difficult to distinguish from infection by other mosquito-borne Flaviviruses due to high sequence similarity, serum antibody cross-reactivity, and virus co-circulation in endemic areas. Indeed, existing serological methods are not able to consistently differentiate ZIKV from other Flaviviruses, which makes it extremely difficult to accurately calculate the incidence rate of Zika-associated Guillain-Barre in adults, microcephaly in newborns, or asymptomatic infections within a geographical area. In order to identify Zika-specific peptide regions that could be used as serology reagents, we have applied comparative genomics and protein structure analyses to identify amino acid residues that distinguish each of 10 Flavivirus species and subtypes from each other by calculating the specificity, sensitivity, and surface exposure of each residue in relevant target proteins. For ZIKV we identified 104 and 116 15-mer peptides in the E glycoprotein and NS1 non-structural protein, respectively, that contain multiple diagnostic sites and are located in surface-exposed regions in the tertiary protein structure. These sensitive, specific, and surface-exposed peptide regions should serve as useful reagents for seroprevalence studies to better distinguish between prior infections with any of these mosquito-borne Flaviviruses. The development of better detection methods and diagnostic tools will enable clinicians and public health workers to more accurately estimate the true incidence rate of asymptomatic infections, neurological syndromes, and birth defects associated with ZIKV infection.

  19. Pathogenesis and Inhibition of Flaviviruses from a Carbohydrate Perspective

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    So Young Kim

    2017-05-01

    Full Text Available Flaviviruses are enveloped, positive single stranded ribonucleic acid (RNA viruses with various routes of transmission. While the type and severity of symptoms caused by pathogenic flaviviruses vary from hemorrhagic fever to fetal abnormalities, their general mechanism of host cell entry is similar. All pathogenic flaviviruses, such as dengue virus, yellow fever virus, West Nile virus, Japanese encephalitis virus, and Zika virus, bind to glycosaminglycans (GAGs through the putative GAG binding sites within their envelope proteins to gain access to the surface of host cells. GAGs are long, linear, anionic polysaccharides with a repeating disaccharide unit and are involved in many biological processes, such as cellular signaling, cell adhesion, and pathogenesis. Flavivirus envelope proteins are N-glycosylated surface proteins, which interact with C-type lectins, dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN through their glycans. In this review, we discuss both host and viral surface receptors that have the carbohydrate components, focusing on the surface interactions in the early stage of flavivirus entry. GAG-flavivirus envelope protein interactions as well as interactions between flavivirus envelope proteins and DC-SIGN are discussed in detail. This review also examines natural and synthetic inhibitors of flaviviruses that are carbohydrate-based or carbohydrate-targeting. Both advantages and drawbacks of these inhibitors are explored, as are potential strategies to improve their efficacy to ultimately help eradicate flavivirus infections.

  20. Flavivirus cell entry and membrane fusion

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    Smit, Jolanda M.; Moesker, Bastiaan; Rodenhuis-Zybert, Izabela; Wilschut, Jan

    2011-01-01

    Flaviviruses, such as dengue virus and West Nile virus, are enveloped viruses that infect cells through receptor-mediated endocytosis and fusion from within acidic endosomes. The cell entry process of flaviviruses is mediated by the viral E glycoprotein. This short review will address recent

  1. A single mutation in the envelope protein modulates flavivirus antigenicity, stability, and pathogenesis.

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    Leslie Goo

    2017-02-01

    Full Text Available The structural flexibility or 'breathing' of the envelope (E protein of flaviviruses allows virions to sample an ensemble of conformations at equilibrium. The molecular basis and functional consequences of virus conformational dynamics are poorly understood. Here, we identified a single mutation at residue 198 (T198F of the West Nile virus (WNV E protein domain I-II hinge that regulates virus breathing. The T198F mutation resulted in a ~70-fold increase in sensitivity to neutralization by a monoclonal antibody targeting a cryptic epitope in the fusion loop. Increased exposure of this otherwise poorly accessible fusion loop epitope was accompanied by reduced virus stability in solution at physiological temperatures. Introduction of a mutation at the analogous residue of dengue virus (DENV, but not Zika virus (ZIKV, E protein also increased accessibility of the cryptic fusion loop epitope and decreased virus stability in solution, suggesting that this residue modulates the structural ensembles sampled by distinct flaviviruses at equilibrium in a context dependent manner. Although the T198F mutation did not substantially impair WNV growth kinetics in vitro, studies in mice revealed attenuation of WNV T198F infection. Overall, our study provides insight into the molecular basis and the in vitro and in vivo consequences of flavivirus breathing.

  2. The Influence of Urbanization Modes on the Spatial Circulation of Flaviviruses within Ouagadougou (Burkina Faso

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    Florence Fournet

    2016-12-01

    Full Text Available Dengue is an emerging infectious disease of global significance. Although this virus has been reported for a long time, its significance within the burden of diseases in West Africa is not obvious, especially in Burkina Faso. Our objective was to evaluate flavivirus presence in Ouagadougou (Burkina Faso and the link between anti-flavivirus antibody seroprevalence and urbanization modes. A population-based cross-sectional survey was conducted and 3015 children were enrolled from Ouagadougou districts with different types and degrees of urbanization (with/without equipment and high/low building density. Flavivirus (FLAV IgM MAC-ELISA and FLAV indirect IgG ELISA were performed. Associations between FLAV IgG presence (sign of past infection and various independent variables were assessed using the chi-square test and a multivariate logistic regression analysis. The apparent prevalence of past flavivirus infections among the enrolled children was 22.7% (95% CI: 22.4–26.7 (n = 685. Eleven children (0.4%; 95% CI: 0.61–2.14 were positive for FLAV IgM, indicating active transmission. Factors associated with flavivirus infection were identified among the enrolled children (age, sex, householders (educational level, asset index and in the environment (building density, water access, waste management and house appearance; however, they showed great variability according to the city districts. The water access modality did not significantly influence FLAV IgG positivity. Conversely, apparently good practices of waste management had unexpected consequences (increased risk related to municipal dumpsters. Given the scale of ongoing urbanization and the spread of arboviral diseases, close collaboration between health and city stakeholders is needed.

  3. Flavivirus RNAi suppression: decoding non-coding RNA

    NARCIS (Netherlands)

    Pijlman, G.P.

    2014-01-01

    Flaviviruses are important human pathogens that are transmitted by invertebrate vectors, mostly mosquitoes and ticks. During replication in their vector, flaviviruses are subject to a potent innate immune response known as antiviral RNA interference (RNAi). This defense mechanism is associated with

  4. The Antigenic Structure of Zika Virus and Its Relation to Other Flaviviruses: Implications for Infection and Immunoprophylaxis

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    Stiasny, Karin

    2017-01-01

    SUMMARY Zika virus was discovered ∼70 years ago in Uganda and maintained a low profile as a human disease agent in Africa and Asia. Only recently has it caused explosive outbreaks in previously unaffected regions, first in Oceania and then in the Americas since 2015. Of special concern is the newly identified link between congenital malformations (especially microcephaly) and Zika virus infections during pregnancy. At present, it is unclear whether Zika virus changed its pathogenicity or whether the huge number of infections allowed the recognition of a previously cryptic pathogenic property. The purpose of this review is to discuss recent data on the molecular antigenic structure of Zika virus in the context of antibody-mediated neutralization and antibody-dependent enhancement (ADE) of infection, a phenomenon that has been implicated in the development of severe disease caused by the related dengue viruses. Emphasis is given to epitopes of antibodies that potently neutralize Zika virus and also to epitopes that provide antigenic links to other important human-pathogenic flaviviruses such as dengue, yellow fever, West Nile, Japanese encephalitis, and tick-borne encephalitis viruses. The antigenic cross talk between Zika and dengue viruses appears to be of special importance, since they cocirculate in many regions of endemicity and sequential infections are likely to occur frequently. New insights into the molecular antigenic structure of Zika virus and flaviviruses in general have provided the foundation for great progress made in developing Zika virus vaccines and antibodies for passive immunization. PMID:28179396

  5. [Detection of flavivirus in mosquitoes (Diptera: Culicidae) from Easter Island-Chile].

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    Collao, Ximena; Prado, Lorena; González, Christian; Vásquez, Ana; Araki, Romina; Henríquez, Tuki; Peña, Cindy M

    2015-02-01

    Flaviviruses are arthropod-borne viruses, mainly by mosquitoes of the genera Aedes and Culex (Culicidae) that are detected in tropical and subtropical areas. Main flaviviruses of public health importance are: dengue, West Nile virus, yellow fever, among others. In continental Chile, flaviviruses has not been detected. However, there are indigenous cases of dengue detected in Easter Island since 2002, as the presence of its vector Aedes aegypti. The aim of this study was: To determine diversity of flavivirus mosquitoes present in Easter Island. Thirty pools of mosquitoes collected in Hanga Roa were analyzed; a RT-PCR nested flavivirus was performed. Thirteen positive samples were detected and the amplification products were sequenced, identifying two specific flavivirus Insect, the Cell fusing agent virus and other related viruses Kamiti River. This is the first study in Chile showed the presence of flavivirus in vectors in Easter Island.

  6. How Flaviviruses Activate and Suppress the Interferon Response

    Directory of Open Access Journals (Sweden)

    Brenda L. Fredericksen

    2010-02-01

    Full Text Available The flavivirus genus includes viruses with a remarkable ability to produce disease on a large scale. The expansion and increased endemicity of dengue and West Nile viruses in the Americas exemplifies their medical and epidemiological importance. The rapid detection of viral infection and induction of the innate antiviral response are crucial to determining the outcome of infection. The intracellular pathogen receptors RIG-I and MDA5 play a central role in detecting flavivirus infections and initiating a robust antiviral response. Yet, these viruses are still capable of producing acute illness in humans. It is now clear that flaviviruses utilize a variety of mechanisms to modulate the interferon response. The non-structural proteins of the various flaviviruses reduce expression of interferon dependent genes by blocking phosphorylation, enhancing degradation or down-regulating expression of major components of the JAK/STAT pathway. Recent studies indicate that interferon modulation is an important factor in the development of severe flaviviral illness. This suggests that an increased understanding of viral-host interactions will facilitate the development of novel therapeutics to treat these viral infections and improved biological models to study flavivirus pathogenesis.

  7. Ecuador Paraiso Escondido Virus, a New Flavivirus Isolated from New World Sand Flies in Ecuador, Is the First Representative of a Novel Clade in the Genus Flavivirus.

    Science.gov (United States)

    Alkan, Cigdem; Zapata, Sonia; Bichaud, Laurence; Moureau, Grégory; Lemey, Philippe; Firth, Andrew E; Gritsun, Tamara S; Gould, Ernest A; de Lamballerie, Xavier; Depaquit, Jérôme; Charrel, Rémi N

    2015-12-01

    A new flavivirus, Ecuador Paraiso Escondido virus (EPEV), named after the village where it was discovered, was isolated from sand flies (Psathyromyia abonnenci, formerly Lutzomyia abonnenci) that are unique to the New World. This represents the first sand fly-borne flavivirus identified in the New World. EPEV exhibited a typical flavivirus genome organization. Nevertheless, the maximum pairwise amino acid sequence identity with currently recognized flaviviruses was 52.8%. Phylogenetic analysis of the complete coding sequence showed that EPEV represents a distinct clade which diverged from a lineage that was ancestral to the nonvectored flaviviruses Entebbe bat virus, Yokose virus, and Sokoluk virus and also the Aedes-associated mosquito-borne flaviviruses, which include yellow fever virus, Sepik virus, Saboya virus, and others. EPEV replicated in C6/36 mosquito cells, yielding high infectious titers, but failed to reproduce either in vertebrate cell lines (Vero, BHK, SW13, and XTC cells) or in suckling mouse brains. This surprising result, which appears to eliminate an association with vertebrate hosts in the life cycle of EPEV, is discussed in the context of the evolutionary origins of EPEV in the New World. The flaviviruses are rarely (if ever) vectored by sand fly species, at least in the Old World. We have identified the first representative of a sand fly-associated flavivirus, Ecuador Paraiso Escondido virus (EPEV), in the New World. EPEV constitutes a novel clade according to current knowledge of the flaviviruses. Phylogenetic analysis of the virus genome showed that EPEV roots the Aedes-associated mosquito-borne flaviviruses, including yellow fever virus. In light of this new discovery, the New World origin of EPEV is discussed together with that of the other flaviviruses. Copyright © 2015 Alkan et al.

  8. Current status of flavivirus vaccines.

    Science.gov (United States)

    Barrett, A D

    2001-12-01

    Although there are approximately 68 flaviviruses recognized, vaccines have been developed to control very few human flavivirus diseases. Licensed live attenuated vaccines have been developed for yellow fever (strain 17D) and Japanese encephalitis (strain SA14-14-2) viruses, and inactivated vaccines have been developed for Japanese encephalitis and tick-borne encephalitis viruses. The yellow fever live attenuated 17D vaccine is one of the most efficacious and safe vaccines developed to date and has been used to immunize more than 300 million people. A number of experimental vaccines are being developed, most notably for dengue. Candidate tetravalent live attenuated dengue vaccines are undergoing clinical trials. Other vaccines are being developed using reverse genetics, DNA vaccines, and recombinant immunogens. In addition, the yellow fever 17D vaccine has been used as a backbone to generate chimeric viruses containing the premembrane and envelope protein genes from other flaviviruses. The "Chimerivax" platform has been used to construct chimeric Japanese encephalitis and dengue viruses that are in different phases of development. Similar strategies are being used by other laboratories.

  9. Antibodies to West Nile virus in asymptomatic mammals, birds, and reptiles in the Yucatan Peninsula of Mexico.

    Science.gov (United States)

    Farfán-Ale, José A; Blitvich, Bradley J; Marlenee, Nicole L; Loroño-Pino, María A; Puerto-Manzano, Fernando; García-Rejón, Julián E; Rosado-Paredes, Elsy P; Flores-Flores, Luis F; Ortega-Salazar, Andres; Chávez-Medina, Jaidy; Cremieux-Grimaldi, Juan C; Correa-Morales, Favián; Hernández-Gaona, Gerson; Méndez-Galván, Jorge F; Beaty, Barry J

    2006-05-01

    Surveillance for evidence of West Nile virus (WNV) infection in taxonomically diverse vertebrates was conducted in the Yucatan Peninsula of Mexico in 2003 and 2004. Sera from 144 horses on Cozumel Island, Quintana Roo State, 415 vertebrates (257 birds, 52 mammals, and 106 reptiles) belonging to 61 species from the Merida Zoo, Yucatan State, and 7 farmed crocodiles in Ciudad del Carmen, Campeche State were assayed for antibodies to flaviviruses. Ninety (62%) horses on Cozumel Island had epitope-blocking enzyme-linked immunosorbent assay (ELISA) antibodies to flaviviruses, of which 75 (52%) were seropositive for WNV by plaque reduction neutralization test (PRNT). Blocking ELISA antibodies to flaviviruses also were detected in 13 (3%) animals in the Merida Zoo, including 7 birds and 2 mammals (a jaguar and coyote) seropositive for WNV by PRNT. Six (86%) crocodiles in Campeche State had PRNT-confirmed WNV infections. All animals were healthy at the time of serum collections and none had a history of WNV-like illness.

  10. Bioinformatics in New Generation Flavivirus Vaccines

    Directory of Open Access Journals (Sweden)

    Penelope Koraka

    2010-01-01

    Full Text Available Flavivirus infections are the most prevalent arthropod-borne infections world wide, often causing severe disease especially among children, the elderly, and the immunocompromised. In the absence of effective antiviral treatment, prevention through vaccination would greatly reduce morbidity and mortality associated with flavivirus infections. Despite the success of the empirically developed vaccines against yellow fever virus, Japanese encephalitis virus and tick-borne encephalitis virus, there is an increasing need for a more rational design and development of safe and effective vaccines. Several bioinformatic tools are available to support such rational vaccine design. In doing so, several parameters have to be taken into account, such as safety for the target population, overall immunogenicity of the candidate vaccine, and efficacy and longevity of the immune responses triggered. Examples of how bio-informatics is applied to assist in the rational design and improvements of vaccines, particularly flavivirus vaccines, are presented and discussed.

  11. Construction characterization and application of Flavivirus infectious clones

    NARCIS (Netherlands)

    Jiang, Xiaohong

    2013-01-01

    The topics in this thesis revolve around a group of plus-strand RNA viruses that belong to the Flavivirus genus, a general introduction of which is presented in Chapter 1. The experimental chapters in this thesis mainly focus on the construction and characterization of flavivirus infectious clones

  12. Viral Interference and Persistence in Mosquito-Borne Flaviviruses

    Directory of Open Access Journals (Sweden)

    Juan Santiago Salas-Benito

    2015-01-01

    Full Text Available Mosquito-borne flaviviruses are important pathogens for humans, and the detection of two or more flaviviruses cocirculating in the same geographic area has often been reported. However, the epidemiological impact remains to be determined. Mosquito-borne flaviviruses are primarily transmitted through Aedes and Culex mosquitoes; these viruses establish a life-long or persistent infection without apparent pathological effects. This establishment requires a balance between virus replication and the antiviral host response. Viral interference is a phenomenon whereby one virus inhibits the replication of other viruses, and this condition is frequently associated with persistent infections. Viral interference and persistent infection are determined by several factors, such as defective interfering particles, competition for cellular factors required for translation/replication, and the host antiviral response. The interaction between two flaviviruses typically results in viral interference, indicating that these viruses share common features during the replicative cycle in the vector. The potential mechanisms involved in these processes are reviewed here.

  13. Novel insect-specific flavivirus isolated from northern Europe

    Science.gov (United States)

    Huhtamo, Eili; Moureau, Gregory; Cook, Shelley; Julkunen, Ora; Putkuri, Niina; Kurkela, Satu; Uzcátegui, Nathalie Y.; Harbach, Ralph E.; Gould, Ernest A.; Vapalahti, Olli; de Lamballerie, Xavier

    2012-01-01

    Mosquitoes collected in Finland were screened for flaviviral RNA leading to the discovery and isolation of a novel flavivirus designated Hanko virus (HANKV). Virus characterization, including phylogenetic analysis of the complete coding sequence, confirmed HANKV as a member of the “insect-specific” flavivirus (ISF) group. HANKV is the first member of this group isolated from northern Europe, and therefore the first northern European ISF for which the complete coding sequence has been determined. HANKV was not transcribed as DNA in mosquito cell culture, which appears atypical for an ISF. HANKV shared highest sequence homology with the partial NS5 sequence available for the recently discovered Spanish Ochlerotatus flavivirus (SOcFV). Retrospective analysis of mitochondrial sequences from the virus-positive mosquito pool suggested an Ochlerotatus mosquito species as the most likely host for HANKV. HANKV and SOcFV may therefore represent a novel group of Ochlerotatus-hosted insect-specific flaviviruses in Europe and further afield. PMID:22999256

  14. Arthropod-borne flaviviruses and RNA interference : seeking new approaches for antiviral therapy

    NARCIS (Netherlands)

    Diosa-Toro, Mayra; Urcuqui-Inchima, Silvio; Smit, Jolanda M

    2013-01-01

    Flaviviruses are the most prevalent arthropod-borne viruses worldwide, and nearly half of the 70 Flavivirus members identified are human pathogens. Despite the huge clinical impact of flaviviruses, there is no specific human antiviral therapy available to treat infection with any of the

  15. Microscopy techniques in flavivirus research.

    Science.gov (United States)

    Chong, Mun Keat; Chua, Anthony Jin Shun; Tan, Terence Tze Tong; Tan, Suat Hoon; Ng, Mah Lee

    2014-04-01

    The Flavivirus genus is composed of many medically important viruses that cause high morbidity and mortality, which include Dengue and West Nile viruses. Various molecular and biochemical techniques have been developed in the endeavour to study flaviviruses. However, microscopy techniques still have irreplaceable roles in the identification of novel virus pathogens and characterization of morphological changes in virus-infected cells. Fluorescence microscopy contributes greatly in understanding the fundamental viral protein localizations and virus-host protein interactions during infection. Electron microscopy remains the gold standard for visualizing ultra-structural features of virus particles and infected cells. New imaging techniques and combinatory applications are continuously being developed to push the limit of resolution and extract more quantitative data. Currently, correlative live cell imaging and high resolution three-dimensional imaging have already been achieved through the tandem use of optical and electron microscopy in analyzing biological specimens. Microscopy techniques are also used to measure protein binding affinities and determine the mobility pattern of proteins in cells. This chapter will consolidate on the applications of various well-established microscopy techniques in flavivirus research, and discuss how recently developed microscopy techniques can potentially help advance our understanding in these membrane viruses. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. A Serological Protein Microarray for Detection of Multiple Cross-Reactive Flavivirus Infections in Horses for Veterinary and Public Health Surveillance.

    Science.gov (United States)

    Cleton, N B; van Maanen, K; Bergervoet, S A; Bon, N; Beck, C; Godeke, G-J; Lecollinet, S; Bowen, R; Lelli, D; Nowotny, N; Koopmans, M P G; Reusken, C B E M

    2017-12-01

    The genus Flavivirus in the family Flaviviridae includes some of the most important examples of emerging zoonotic arboviruses that are rapidly spreading across the globe. Japanese encephalitis virus (JEV), West Nile virus (WNV), St. Louis encephalitis virus (SLEV) and Usutu virus (USUV) are mosquito-borne members of the JEV serological group. Although most infections in humans are asymptomatic or present with mild flu-like symptoms, clinical manifestations of JEV, WNV, SLEV, USUV and tick-borne encephalitis virus (TBEV) can include severe neurological disease and death. In horses, infection with WNV and JEV can lead to severe neurological disease and death, while USUV, SLEV and TBEV infections are mainly asymptomatic, however, and induce antibody responses. Horses often serve as sentinels to monitor active virus circulation in serological surveillance programmes specifically for WNV, USUV and JEV. Here, we developed and validated a NS1-antigen protein microarray for the serological differential diagnosis of flavivirus infections in horses using sera of experimentally and naturally infected symptomatic as well as asymptomatic horses. Using samples from experimentally infected horses, an IgG and IgM specificity of 100% and a sensitivity of 95% for WNV and 100% for JEV was achieved with a cut-off titre of 1 : 20 based on ROC calculation. In field settings, the microarray identified 93-100% of IgG-positive horses with recent WNV infections and 87% of TBEV IgG-positive horses. WNV IgM sensitivity was 80%. Differentiation between closely related flaviviruses by the NS1-antigen protein microarray is possible, even though we identified some instances of cross-reactivity among antibodies. However, the assay is not able to differentiate between naturally infected horses and animals vaccinated with an inactivated WNV whole-virus vaccine. We showed that the NS1-microarray can potentially be used for diagnosing and distinguishing flavivirus infections in horses and for public

  17. Universal primers that amplify RNA from all three flavivirus subgroups

    Directory of Open Access Journals (Sweden)

    Barnard Ross T

    2008-01-01

    Full Text Available Abstract Background Species within the Flavivirus genus pose public health problems around the world. Increasing cases of Dengue and Japanese encephalitis virus in Asia, frequent outbreaks of Yellow fever virus in Africa and South America, and the ongoing spread of West Nile virus throughout the Americas, show the geographical burden of flavivirus diseases. Flavivirus infections are often indistinct from and confused with other febrile illnesses. Here we review the specificity of published primers, and describe a new universal primer pair that can detect a wide range of flaviviruses, including viruses from each of the recognised subgroups. Results Bioinformatic analysis of 257 published full-length Flavivirus genomes revealed conserved regions not previously targeted by primers. Two degenerate primers, Flav100F and Flav200R were designed from these regions and used to generate an 800 base pair cDNA product. The region amplified encoded part of the methyltransferase and most of the RNA-dependent-RNA-polymerase (NS5 coding sequence. One-step RT-PCR testing was successful using standard conditions with RNA from over 60 different flavivirus strains representing about 50 species. The cDNA from each virus isolate was sequenced then used in phylogenetic analyses and database searches to confirm the identity of the template RNA. Conclusion Comprehensive testing has revealed the broad specificity of these primers. We briefly discuss the advantages and uses of these universal primers.

  18. Dating the origin of the genus Flavivirus in the light of Beringian biogeography.

    Science.gov (United States)

    Pettersson, John H-O; Fiz-Palacios, Omar

    2014-09-01

    The genus Flavivirus includes some of the most important human viral pathogens, and its members are found in all parts of the populated world. The temporal origin of diversification of the genus has long been debated due to the inherent problems with dating deep RNA virus evolution. A generally accepted hypothesis suggests that Flavivirus emerged within the last 10 000 years. However, it has been argued that the tick-borne Powassan flavivirus was introduced into North America some time between the opening and closing of the Beringian land bridge that connected Asia and North America 15 000-11 000 years ago, indicating an even older origin for Flavivirus. To determine the temporal origin of Flavivirus, we performed Bayesian relaxed molecular clock dating on a dataset with high coverage of the presently available Flavivirus diversity by combining tip date calibrations and internal node calibration, based on the Powassan virus and Beringian land bridge biogeographical event. Our analysis suggested that Flavivirus originated ~85 000 (64 000-110 000) or 120 000 (87 000-159 000) years ago, depending on the circumscription of the genus. This is significantly older than estimated previously. In light of our results, we propose that it is likely that modern humans came in contact with several members of the genus Flavivirus much earlier than suggested previously, and that it is possible that the spread of several flaviviruses coincided with, and was facilitated by, the migration and population expansion of modern humans out of Africa. © 2014 The Authors.

  19. Dissection of antibody specificities induced by yellow fever vaccination.

    Directory of Open Access Journals (Sweden)

    Oksana Vratskikh

    Full Text Available The live attenuated yellow fever (YF vaccine has an excellent record of efficacy and one dose provides long-lasting immunity, which in many cases may last a lifetime. Vaccination stimulates strong innate and adaptive immune responses, and neutralizing antibodies are considered to be the major effectors that correlate with protection from disease. Similar to other flaviviruses, such antibodies are primarily induced by the viral envelope protein E, which consists of three distinct domains (DI, II, and III and is presented at the surface of mature flavivirions in an icosahedral arrangement. In general, the dominance and individual variation of antibodies to different domains of viral surface proteins and their impact on neutralizing activity are aspects of humoral immunity that are not well understood. To gain insight into these phenomena, we established a platform of immunoassays using recombinant proteins and protein domains that allowed us to dissect and quantify fine specificities of the polyclonal antibody response after YF vaccination in a panel of 51 vaccinees as well as determine their contribution to virus neutralization by serum depletion analyses. Our data revealed a high degree of individual variation in antibody specificities present in post-vaccination sera and differences in the contribution of different antibody subsets to virus neutralization. Irrespective of individual variation, a substantial proportion of neutralizing activity appeared to be due to antibodies directed to complex quaternary epitopes displayed on the virion surface only but not on monomeric E. On the other hand, DIII-specific antibodies (presumed to have the highest neutralizing activity as well as broadly flavivirus cross-reactive antibodies were absent or present at very low titers. These data provide new information on the fine specificity as well as variability of antibody responses after YF vaccination that are consistent with a strong influence of individual

  20. Flavivirus internalization is regulated by a size-dependent endocytic pathway.

    Science.gov (United States)

    Hackett, Brent A; Cherry, Sara

    2018-04-17

    Flaviviruses enter host cells through the process of clathrin-mediated endocytosis, and the spectrum of host factors required for this process are incompletely understood. Here we found that lymphocyte antigen 6 locus E (LY6E) promotes the internalization of multiple flaviviruses, including West Nile virus, Zika virus, and dengue virus. Perhaps surprisingly, LY6E is dispensable for the internalization of the endogenous cargo transferrin, which is also dependent on clathrin-mediated endocytosis for uptake. Since viruses are substantially larger than transferrin, we reasoned that LY6E may be required for uptake of larger cargoes and tested this using transferrin-coated beads of similar size as flaviviruses. LY6E was indeed required for the internalization of transferrin-coated beads, suggesting that LY6E is selectively required for large cargo. Cell biological studies found that LY6E forms tubules upon viral infection and bead internalization, and we found that tubule formation was dependent on RNASEK, which is also required for flavivirus internalization, but not transferrin uptake. Indeed, we found that RNASEK is also required for the internalization of transferrin-coated beads, suggesting it functions upstream of LY6E. These LY6E tubules resembled microtubules, and we found that microtubule assembly was required for their formation and flavivirus uptake. Since microtubule end-binding proteins link microtubules to downstream activities, we screened the three end-binding proteins and found that EB3 promotes virus uptake and LY6E tubularization. Taken together, these results highlight a specialized pathway required for the uptake of large clathrin-dependent endocytosis cargoes, including flaviviruses. Copyright © 2018 the Author(s). Published by PNAS.

  1. Detection of mosquito-only flaviviruses in Europe

    Czech Academy of Sciences Publication Activity Database

    Calzolari, M.; Zé-Zé, L.; Růžek, Daniel; Vazquez, A.; Jeffries, C.; Defilippo, F.; Osório, H.C.; Kilian, Patrik; Ruíz, S.; Fooks, A. R.; Maioli, G.; Amaro, F.; Tlustý, M.; Figuerola, J.; Medlock, J. M.; Bonilauri, P.; Alves, M. J.; Šebesta, Oldřich; Tenorio, A.; Vaux, A. G. C.; Bellini, R.; Gelbič, Ivan; Sánchez-Seco, M. P.; Johnson, N.; Dottori, M.

    2012-01-01

    Roč. 93, č. 6 (2012), s. 1215-1225 ISSN 0022-1317 R&D Projects: GA MŠk 2B08003; GA MŠk(CZ) LC06009; GA ČR GD206/09/H026 Institutional research plan: CEZ:AV0Z60220518; CEZ:AV0Z50070508; CEZ:AV0Z60930519 Keywords : WEST-NILE-VIRUS * INSECT-SPECIFIC FLAVIVIRUSES * POLYMERASE CHAIN-REACTION * FUSING AGENT VIRUS * AEDES-ALBOPICTUS * CULEX FLAVIVIRUS * DIPTERA-CULICIDAE * PHYLOGENETIC ANALYSIS * SURVEILLANCE * TRANSMISSION Subject RIV: EC - Immunology Impact factor: 3.127, year: 2012 http://link.springer.com/article/10.1007%2Fs00436-012-2928-4

  2. Compensating for cross-reactions using avidity and computation in a suspension multiplex immunoassay for serotyping of Zika versus other flavivirus infections.

    Science.gov (United States)

    Rönnberg, Bengt; Gustafsson, Åke; Vapalahti, Olli; Emmerich, Petra; Lundkvist, Åke; Schmidt-Chanasit, Jonas; Blomberg, Jonas

    2017-10-01

    The recent spread of Zika virus (ZIKV) in the Americas and Asia necessitates an increased preparedness for improved maternal and perinatal health and blood safety. However, serological cross-reactions, especially to Dengue virus (DENV), complicate ZIKV antibody serodiagnosis. A novel "pan-Flavi" suspension multiplex immunoassay (PFSMIA) using 25 antigens, whole virus (WV), non-structural protein 1 (NS1), and envelope (E) proteins, from 7 zoonotic flaviviruses for specific detection of ZIKV and DENV IgM and IgG was developed. Patterns of antibody cross-reactivity, avidity, and kinetics were established in 104 sera from returning travelers with known ZIKV and DENV infections. PFSMIA gave IgM- and IgG-sensitivities for both viruses of 96-100%, compared to an immunofluorescence assay. Main IgM cross-reactions were to NS1, for IgG to the E and WV antigens. Infecting virus yielded reactivity to several antigens of the homologous virus, while cross-reactions tended to occur only to a single antigen from heterologous virus(es). A specificity-enhancing computer procedure took into account antibody isotype, number of antibody-reactive antigens per virus, avidity, average degree of cross-reactivity to heterologous flavivirus antigens, and reactivity changes in serial sera. It classified all 50 cases correctly. Applied to sera from 200 pregnant women and 173 blood donors from Sweden, one blood donor was found ZIKV NS1 IgM positive, and another as ZIKV NS1 IgG positive. These samples did not react with other ZIKV antigens and were thereby judged as false-positives. PFSMIA provided sensitive and specific ZIKV and DENV serology, warranting high-throughput serological surveillance and a minimized need for laborious and expensive virus neutralization assays.

  3. Membrane and envelope virus proteins co-expressed as lysosome associated membrane protein (LAMP fused antigens: a potential tool to develop DNA vaccines against flaviviruses

    Directory of Open Access Journals (Sweden)

    Rafael Dhalia

    2009-12-01

    Full Text Available Vaccination is the most practical and cost-effective strategy to prevent the majority of the flavivirus infection to which there is an available vaccine. However, vaccines based on attenuated virus can potentially promote collateral side effects and even rare fatal reactions. Given this scenario, the developent of alternative vaccination strategies such as DNA-based vaccines encoding specific flavivirus sequences are being considered. Endogenous cytoplasmic antigens, characteristically plasmid DNA-vaccine encoded, are mainly presented to the immune system through Major Histocompatibility Complex class I - MHC I molecules. The MHC I presentation via is mostly associated with a cellular cytotoxic response and often do not elicit a satisfactory humoral response. One of the main strategies to target DNA-encoded antigens to the MHC II compartment is expressing the antigen within the Lysosome-Associated Membrane Protein (LAMP. The flavivirus envelope protein is recognized as the major virus surface protein and the main target for neutralizing antibodies. Different groups have demonstrated that co-expression of flavivirus membrane and envelope proteins in mammalian cells, fused with the carboxyl-terminal of LAMP, is able to induce satisfactory levels of neutralizing antibodies. Here we reviewed the use of the envelope flavivirus protein co-expression strategy as LAMP chimeras with the aim of developing DNA vaccines for dengue, West Nile and yellow fever viruses.A vacinação é a estratégia mais prática e o melhor custo-benefício para prevenir a maioria das infecções dos flavivirus, para os quais existe vacina disponível. Entretanto, as vacinas baseadas em vírus atenuados podem potencialmente promover efeitos colaterais e, mais raramente, reações fatais. Diante deste cenário, o desenvolvimento de estratégias alternativas de vacinação, como vacinas baseadas em DNA codificando seqüências específicas dos flavivirus, está sendo considerado

  4. Genetic recombination of tick-borne flaviviruses among wild-type strains.

    Science.gov (United States)

    Norberg, Peter; Roth, Anette; Bergström, Tomas

    2013-06-05

    Genetic recombination has been suggested to occur in mosquito-borne flaviviruses. In contrast, tick-borne flaviviruses have been thought to evolve in a clonal manner, although recent studies suggest that recombination occurs also for these viruses. We re-analyzed the data and found that previous conclusions on wild type recombination were probably falsely drawn due to misalignments of nucleotide sequences, ambiguities in GenBank sequences, or different laboratory culture histories suggestive of recombination events in laboratory. To evaluate if reliable predictions of wild type recombination of tick-borne flaviviruses can be made, we analyzed viral strains sequenced exclusively for this study, and other flavivirus sequences retrieved from GenBank. We detected genetic signals supporting recombination between viruses within the three clades of TBEV-Eu, TBEV-Sib and TBEV-Fe, respectively. Our results suggest that the tick-borne encephalitis viruses may undergo recombination under natural conditions, but that geographic barriers restrict most recombination events to involve only closely genetically related viruses. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Construction of human antibody gene libraries and selection of antibodies by phage display.

    Science.gov (United States)

    Frenzel, André; Kügler, Jonas; Wilke, Sonja; Schirrmann, Thomas; Hust, Michael

    2014-01-01

    Antibody phage display is the most commonly used in vitro selection technology and has yielded thousands of useful antibodies for research, diagnostics, and therapy.The prerequisite for successful generation and development of human recombinant antibodies using phage display is the construction of a high-quality antibody gene library. Here, we describe the methods for the construction of human immune and naive scFv gene libraries.The success also depends on the panning strategy for the selection of binders from these libraries. In this article, we describe a panning strategy that is high-throughput compatible and allows parallel selection in microtiter plates.

  6. Bioinformatics in new generation flavivirus vaccines

    NARCIS (Netherlands)

    A.D.M.E. Osterhaus (Albert); P. Koraka (Penelope); B.E.E. Martina (Byron)

    2010-01-01

    textabstractFlavivirus infections are the most prevalent arthropod-borne infections world wide, often causing severe disease especially among children, the elderly, and the immunocompromised. In the absence of effective antiviral treatment, prevention through vaccination would greatly reduce

  7. Expectoration of Flaviviruses during sugar feeding by mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    van den Hurk, Andrew F; Johnson, Petrina H; Hall-Mendelin, Sonja; Northill, Judy A; Simmons, Russell J; Jansen, Cassie C; Frances, Stephen P; Smith, Greg A; Ritchie, Scott A

    2007-09-01

    Biological transmission of arboviruses to a vertebrate host occurs when virions are expelled along with saliva during blood feeding by a hematophagous arthropod. We undertook experiments to determine whether mosquitoes expectorate flaviviruses in their saliva while sugar feeding. Batches of Culex annulirostris Skuse and Culex gelidus Theobald (Diptera: Culicidae) were orally infected with Japanese encephalitis (family Flaviviridae, genus Flavivirus, JEV), Kunjin (family Flaviviridae, genus Flavivirus, KUNV; a subtype of West Nile virus), and Murray Valley encephalitis (family Flaviviridae, genus Flavivirus, MVEV) viruses. After a 7-d extrinsic incubation, these mosquitoes were offered sucrose meals via cotton pledgets, which were removed daily and processed for viral RNA by using real-time TaqMan reverse transcriptase-polymerase chain reaction (RT-PCR) assays. JEV, MVEV, and KUNV RNA was detected in all pledgets removed from batches of Cx. gelidus on days 7-14 postexposure. In contrast, detection rates were variable for Cx. annulirostris, with KUNV detected in 0.3 M sucrose pledgets on all days postexposure, and JEV and MVEV detected on 57 and 50% of days postexposure, respectively. Higher concentrations of sucrose in the pledget did not increase virus detection rates. When individual JEV-infected Cx. gelidus were exposed to the sucrose pledget, 73% of mosquitoes expectorated virus with titers that were detectable by TaqMan RT-PCR. These results clearly show that flaviviruses are expectorated by infected mosquitoes during the process of sugar feeding on artificial pledgets. Potential applications of the method for arboviral bioassays and field surveillance are discussed.

  8. Evidence for ribosomal frameshifting and a novel overlapping gene in the genomes of insect-specific flaviviruses

    International Nuclear Information System (INIS)

    Firth, Andrew E.; Blitvich, Bradley J.; Wills, Norma M.; Miller, Cathy L.; Atkins, John F.

    2010-01-01

    Flaviviruses have a positive-sense, single-stranded RNA genome of ∼11 kb, encoding a large polyprotein that is cleaved to produce ∼10 mature proteins. Cell fusing agent virus, Kamiti River virus, Culex flavivirus and several recently discovered flaviviruses have no known vertebrate host and apparently infect only insects. We present compelling bioinformatic evidence for a 253-295 codon overlapping gene (designated fifo) conserved throughout these insect-specific flaviviruses and immunofluorescent detection of its product. Fifo overlaps the NS2A/NS2B coding sequence in the - 1/+ 2 reading frame and is most likely expressed as a trans-frame fusion protein via ribosomal frameshifting at a conserved GGAUUUY slippery heptanucleotide with 3'-adjacent RNA secondary structure (which stimulates efficient frameshifting in vitro). The discovery bears striking parallels to the recently discovered ribosomal frameshifting site in the NS2A coding sequence of the Japanese encephalitis serogroup of flaviviruses and suggests that programmed ribosomal frameshifting may be more widespread in flaviviruses than currently realized.

  9. New insights into flavivirus evolution, taxonomy and biogeographic history, extended by analysis of canonical and alternative coding sequences.

    Directory of Open Access Journals (Sweden)

    Gregory Moureau

    Full Text Available To generate the most diverse phylogenetic dataset for the flaviviruses to date, we determined the genomic sequences and phylogenetic relationships of 14 flaviviruses, of which 10 are primarily associated with Culex spp. mosquitoes. We analyze these data, in conjunction with a comprehensive collection of flavivirus genomes, to characterize flavivirus evolutionary and biogeographic history in unprecedented detail and breadth. Based on the presumed introduction of yellow fever virus into the Americas via the transatlantic slave trade, we extrapolated a timescale for a relevant subset of flaviviruses whose evolutionary history, shows that different Culex-spp. associated flaviviruses have been introduced from the Old World to the New World on at least five separate occasions, with 2 different sets of factors likely to have contributed to the dispersal of the different viruses. We also discuss the significance of programmed ribosomal frameshifting in a central region of the polyprotein open reading frame in some mosquito-associated flaviviruses.

  10. Exploring of primate models of tick-borne flaviviruses infection for evaluation of vaccines and drugs efficacy.

    Directory of Open Access Journals (Sweden)

    Natalia S Pripuzova

    Full Text Available Tick-borne encephalitis virus (TBEV is one of the most prevalent and medically important tick-borne arboviruses in Eurasia. There are overlapping foci of two flaviviruses: TBEV and Omsk hemorrhagic fever virus (OHFV in Russia. Inactivated vaccines exist only against TBE. There are no antiviral drugs for treatment of both diseases. Optimal animal models are necessary to study efficacy of novel vaccines and treatment preparations against TBE and relative flaviviruses. The models for TBE and OHF using subcutaneous inoculation were tested in Cercopithecus aethiops and Macaca fascicularis monkeys with or without prior immunization with inactivated TBE vaccine. No visible clinical signs or severe pathomorphological lesions were observed in any monkey infected with TBEV or OHFV. C. aethiops challenged with OHFV showed massive hemolytic syndrome and thrombocytopenia. Infectious virus or viral RNA was revealed in visceral organs and CNS of C. aethiops infected with both viruses; however, viremia was low. Inactivated TBE vaccines induced high antibody titers against both viruses and expressed booster after challenge. The protective efficacy against TBE was shown by the absence of virus in spleen, lymph nodes and CNS of immunized animals after challenge. Despite the absence of expressed hemolytic syndrome in immunized C. aethiops TBE vaccine did not prevent the reproduction of OHFV in CNS and visceral organs. Subcutaneous inoculation of M. fascicularis with two TBEV strains led to a febrile disease with well expressed viremia, fever, and virus reproduction in spleen, lymph nodes and CNS. The optimal terms for estimation of the viral titers in CNS were defined as 8-16 days post infection. We characterized two animal models similar to humans in their susceptibility to tick-borne flaviviruses and found the most optimal scheme for evaluation of efficacy of preventive and therapeutic preparations. We also identified M. fascicularis to be more susceptible to

  11. Stress responses in flavivirus-infected cells: activation of unfolded protein response and autophagy

    Directory of Open Access Journals (Sweden)

    Ana-Belén eBlázquez

    2014-06-01

    Full Text Available The Flavivirus is a genus of RNA viruses that includes multiple long known human, animal and zoonotic pathogens such as Dengue virus, yellow fever virus, West Nile virus or Japanese encephalitis virus, as well as other less known viruses that represent potential threats for human and animal health such as Usutu or Zika viruses. Flavivirus replication is based on endoplasmic reticulum-derived structures. Membrane remodeling and accumulation of viral factors induce endoplasmic reticulum stress that results in activation of a cellular signaling response termed unfolded protein response (UPR, which can be modulated by the viruses for their own benefit. Concomitant with the activation of the UPR, an upregulation of the autophagic pathway in cells infected with different flaviviruses has also been described. This review addresses the current knowledge of the relationship between endoplasmic reticulum stress, UPR and autophagy in flavivirus-infected cells and the growing evidences for an involvement of these cellular pathways in the replication and pathogenesis of these viruses.

  12. The Naive Central Banker

    Directory of Open Access Journals (Sweden)

    Marcelo de Carvalho Griebeler

    2015-09-01

    Full Text Available There has been in some countries a trend of assigning other functions to central banks besides price stability. The most suggested function to be added to monetary authority’s obligations is to pursue economic growth or full employment. In this paper we characterize the behavior and analyse the optimal monetary policy of, what we call, a naive central banker. We describe the naive behavior as one that does face the inflation-unemployment trade-off, but it tries to minimize both variables simultaneously. Our findings, both under discretion and commitment, indicate that the naive central banker delivers lower expected inflation and inflation variance than the benchmark behavior whenever the economy is rigid enough. However, the degree of conservativeness also affects this result, such that the less conservative the naive policymaker, the more rigidity is necessary.

  13. Flavivirus methyltransferase as target for virus treatment

    Czech Academy of Sciences Publication Activity Database

    Krafčíková, Petra; Chalupská, Dominika; Hercík, Kamil; Nencka, Radim; Bouřa, Evžen

    2017-01-01

    Roč. 284, Suppl 1 (2017), s. 216-217 ISSN 1742-464X. [FEBS Congress /42./ From Molecules to Cells and Back. 10.09.2017-14.09.2017, Jerusalem] Institutional support: RVO:61388963 Keywords : flavivirus methyltransferase * antivirals Subject RIV: CE - Biochemistry

  14. Cacipacore virus as an emergent mosquito-borne Flavivirus

    Directory of Open Access Journals (Sweden)

    Mario Luis Garcia de Figueiredo

    Full Text Available Abstract INTRODUCTION: Cacipacore virus (CPCV, a possible bird-associated flavivirus, has yet to be detected in mosquitoes. Our purpose is examining CPCV in mosquitoes from the Amazon region of Brazil. METHODS: Approximately 3,253 Culicidae (grouped into 264 pools were collected from the Amazon region during 2002-2006 and analyzed using a Flavivirus genus-specific reverse transcription- polymerase chain reaction followed by nested polymerase chain reaction assay and by nucleotide sequencing of amplicons. RESULTS: Nucleotide sequences from five mosquito samples showed high similarity to the those of CPCV originally isolated in the Amazon region. CONCLUSIONS: This is the first report of CPCV-infected mosquitoes which has implications on the arbovirus maintenance in nature and transmission to man.

  15. Zika Vaccine Development: Flavivirus Foils

    Science.gov (United States)

    2016-09-01

    Martins, Bavari, Zika Vaccine Development 1 Zika Vaccine Development: Flavivirus Foils Martins KAO, Bavari S. The current Zika virus...States government. The rapid response to Zika is perhaps the first of its kind, and it undoubtedly has been made possible by the lessons learned from...the response to the 2014 Ebola virus outbreak in West Africa. However, Zika virus is not Ebola virus. As of February 2016 there were only 296

  16. Naive Physics Perplex

    OpenAIRE

    Davis, Ernest

    1998-01-01

    The "Naive Physics Manifesto" of Pat Hayes (1978) proposes a large-scale project to develop a formal theory encompassing the entire knowledge of physics of naive reasoners, expressed in a declarative symbolic form. The theory is organized in clusters of closely interconnected concepts and axioms. More recent work on the representation of commonsense physical knowledge has followed a somewhat different methodology. The goal has been to develop a competence theory powerful enough to justify com...

  17. Duck egg-drop syndrome caused by BYD virus, a new Tembusu-related flavivirus.

    Directory of Open Access Journals (Sweden)

    Jingliang Su

    Full Text Available Since April 2010, a severe outbreak of duck viral infection, with egg drop, feed uptake decline and ovary-oviduct disease, has spread around the major duck-producing regions in China. A new virus, named BYD virus, was isolated in different areas, and a similar disease was reproduced in healthy egg-producing ducks, infecting with the isolated virus. The virus was re-isolated from the affected ducks and replicated well in primary duck embryo fibroblasts and Vero cells, causing the cytopathic effect. The virus was identified as an enveloped positive-stranded RNA virus with a size of approximately 55 nm in diameter. Genomic sequencing of the isolated virus revealed that it is closely related to Tembusu virus (a mosquito-borne Ntaya group flavivirus, with 87-91% nucleotide identity of the partial E (envelope proteins to that of Tembusu virus and 72% of the entire genome coding sequence with Bagaza virus, the most closely related flavivirus with an entirely sequenced genome. Collectively our systematic studies fulfill Koch's postulates, and therefore, the causative agent of the duck egg drop syndrome occurring in China is a new flavivirus. Flavivirus is an emerging and re-emerging zoonotic pathogen and BYD virus that causes severe egg-drop, could be disastrous for the duck industry. More importantly its public health concerns should also be evaluated, and its epidemiology should be closely watched due to the zoonotic nature of flaviviruses.

  18. A novel flavivirus detected in two Aedes spp. collected near the demilitarized zone of the Republic of Korea.

    Science.gov (United States)

    Korkusol, Achareeya; Takhampunya, Ratree; Hang, Jun; Jarman, Richard G; Tippayachai, Bousaraporn; Kim, Heung-Chul; Chong, Sung-Tae; Davidson, Silas A; Klein, Terry A

    2017-05-01

    Flaviviruses comprise a large and diverse group of positive-stranded RNA viruses, including tick-, mosquito- and unknown-vector-borne flaviviruses. A novel flavivirus was detected in pools of Aedes vexans nipponii (n=1) and Aedes esoensis (n=3) collected in 2012 and 2013 near the demilitarized zone (DMZ), Republic of Korea (ROK). Phylogenetic analyses of the NS5, E gene and complete polyprotein coding sequence (CDS) showed that the novel virus fell within the Aedes-borne flaviviruses (ABFVs), with nucleotide identity ranging from 57.8-75.1 %, 46.1-74.2 % and 51.1-76.2 %, respectively. While the novel ABFV was distant from other flaviviruses within the group, it formed a clade with Ilomantsi virus (ILOV). Sequence alignments of the partial NS5 gene, full-length E gene and polyprotein CDS between the novel virus and ILOV showed approximately 76.2 % nucleotide identity and 90 % amino acid identity, respectively. The ABFV identified in Aedes mosquitoes from the ROK is a novel ABFV based on the sequence analyses and is designated as Panmunjeom flavivirus (PANFV).

  19. Construction and biological characterization of artificial recombinants between a wild type flavivirus (Kunjin) and a live chimeric flavivirus vaccine (ChimeriVax-JE).

    Science.gov (United States)

    Pugachev, Konstantin V; Schwaiger, Julia; Brown, Nathan; Zhang, Zhen-xi; Catalan, John; Mitchell, Frederick S; Ocran, Simeon W; Rumyantsev, Alexander A; Khromykh, Alexander A; Monath, Thomas P; Guirakhoo, Farshad

    2007-09-17

    Although the theoretical concern of genetic recombination has been raised related to the use of live attenuated flavivirus vaccines [Seligman, Gould, Lancet 2004;363:2073-5], it has little foundation [e.g., Monath TP, Kanesa-Thasan N, Guirakhoo F, Pugachev K, Almond J, Lang J, et al. Vaccine 2005;23:2956-8]. To investigate biological effects of recombination between a chimeric yellow fever (YF) 17D/Japanese encephalitis (JE) vaccine virus (ChimeriVax-JE) and a wild-type flavivirus Kunjin (KUN-cDNA), the prM-E envelope protein genes were swapped between the two viruses, resulting in new YF 17D/KUN(prM-E) and KUN/JE(prM-E) chimeras. The prM-E genes are easily exchangeable between flavivirues, and thus the exchange was expected to yield the most replication-competent chimeras, while other rationally designed recombinants would be more likely to be crippled or non-viable. The new chimeras proved highly attenuated in comparison with the KUN-cDNA parent, as judged by plaque size and growth kinetics in cell culture, low viremia in hamsters, and reduced neurovirulence/neuroinvasiveness in mice. These data provide strong experimental evidence that the potential of recombinants, should they ever emerge, to cause disease or spread (compete in nature with wild-type flaviviruses) would be indeed extremely low.

  20. Flavivirus NS3 and NS5 proteins interaction network: a high-throughput yeast two-hybrid screen

    Directory of Open Access Journals (Sweden)

    Canard Bruno

    2011-10-01

    Full Text Available Abstract Background The genus Flavivirus encompasses more than 50 distinct species of arthropod-borne viruses, including several major human pathogens, such as West Nile virus, yellow fever virus, Japanese encephalitis virus and the four serotypes of dengue viruses (DENV type 1-4. Each year, flaviviruses cause more than 100 million infections worldwide, some of which lead to life-threatening conditions such as encephalitis or haemorrhagic fever. Among the viral proteins, NS3 and NS5 proteins constitute the major enzymatic components of the viral replication complex and are essential to the flavivirus life cycle. Results We report here the results of a high-throughput yeast two-hybrid screen to identify the interactions between human host proteins and the flavivirus NS3 and NS5 proteins. Using our screen results and literature curation, we performed a global analysis of the NS3 and NS5 cellular targets based on functional annotation with the Gene Ontology features. We finally created the first flavivirus NS3 and NS5 proteins interaction network and analysed the topological features of this network. Our proteome mapping screen identified 108 human proteins interacting with NS3 or NS5 proteins or both. The global analysis of the cellular targets revealed the enrichment of host proteins involved in RNA binding, transcription regulation, vesicular transport or innate immune response regulation. Conclusions We proposed that the selective disruption of these newly identified host/virus interactions could represent a novel and attractive therapeutic strategy in treating flavivirus infections. Our virus-host interaction map provides a basis to unravel fundamental processes about flavivirus subversion of the host replication machinery and/or immune defence strategy.

  1. The development of flavivirus vaccines | Pulmanausahakul | African ...

    African Journals Online (AJOL)

    Vaccine development to eliminate flaviviral infections has been marked by uneven progress and a large number of setbacks. To date, no single approach has proved successful in leading to vaccine development against a wide range of flaviviruses, but the application of modern techniques to the problem is opening up new ...

  2. Functions and requirements of conserved RNA structures in the 3’ untranslated region of Flaviviruses

    NARCIS (Netherlands)

    Agostinho Gonçalves Costa da Silva, Patrícia

    2011-01-01

    The Flavivirus genus contains nearly 80 viruses, including many important human pathogens such as dengue virus, yellow fever virus, West Nile virus and tick-borne encephalitis virus. To reduce and prevent the impact of flavivirus infection on society, vaccines and effective therapies are required.

  3. Dual miRNA targeting restricts host range and attenuates neurovirulence of flaviviruses.

    Directory of Open Access Journals (Sweden)

    Konstantin A Tsetsarkin

    2015-04-01

    Full Text Available Mosquito-borne flaviviruses are among the most significant arboviral pathogens worldwide. Vaccinations and mosquito population control programs remain the most reliable means for flavivirus disease prevention, and live attenuated viruses remain one of the most attractive flavivirus vaccine platforms. Some live attenuated viruses are capable of infecting principle mosquito vectors, as demonstrated in the laboratory, which in combination with their intrinsic genetic instability could potentially lead to a vaccine virus reversion back to wild-type in nature, followed by introduction and dissemination of potentially dangerous viral strains into new geographic locations. To mitigate this risk we developed a microRNA-targeting approach that selectively restricts replication of flavivirus in the mosquito host. Introduction of sequences complementary to a mosquito-specific mir-184 and mir-275 miRNAs individually or in combination into the 3'NCR and/or ORF region resulted in selective restriction of dengue type 4 virus (DEN4 replication in mosquito cell lines and adult Aedes mosquitos. Moreover a combined targeting of DEN4 genome with mosquito-specific and vertebrate CNS-specific mir-124 miRNA can silence viral replication in two evolutionally distant biological systems: mosquitoes and mouse brains. Thus, this approach can reinforce the safety of newly developed or existing vaccines for use in humans and could provide an additional level of biosafety for laboratories using viruses with altered pathogenic or transmissibility characteristics.

  4. Hepatitis C virus epitope exposure and neutralization by antibodies is affected by time and temperature

    DEFF Research Database (Denmark)

    Sabo, Michelle C; Luca, Vincent C; Ray, Stuart C

    2012-01-01

    A recent study with flaviviruses suggested that structural dynamics of the virion impact antibody neutralization via exposure of ostensibly cryptic epitopes. To determine whether this holds true for the distantly related hepatitis C virus (HCV), whose neutralizing epitopes may be obscured...... by a glycan shield, apolipoprotein interactions, and the hypervariable region on the E2 envelope protein, we assessed how time and temperature of pre-incubation altered monoclonal antibody (MAb) neutralization of HCV. Notably, several MAbs showed increased inhibitory activity when pre-binding was performed...

  5. FORMATION OF INNATE AND ADAPTIVE IMMUNE RESPONSE UNDER THE INFLUENCE OF DIFFERENT FLAVIVIRUS VACCINES

    Directory of Open Access Journals (Sweden)

    N. V. Krylova

    2015-01-01

    Full Text Available The review examines in a comparative perspective the key moments of formation of innate and adaptive immune responses to different types of current flavivirus vaccines: live attenuated against yellow fever virus and inactivated whole virus against tick-borne encephalitis virus. Particular attention is paid to the ability of these different vaccines, containing exogenous pathogen-associated molecular structures, to stimulate innate immunity. Live attenuated vaccine by infecting several subtypes of dendritic cells activates them through various pattern-recognition receptors, such as Tolland RIG-I-like receptors, which leads to significant production of proinflammatory cytokines, including interferon-α primary mediator of innate antiviral immunity. By simulating natural viral infection, this vaccine quickly spreads over the vascular network, and the dendritic cells, activated by it, migrate to the draining lymph nodes and trigger multiple foci of Tand B-cell activation. Inactivated vaccine stimulates the innate immunity predominantly at the injection site, and for the sufficient activation requires the presence in its composition of an adjuvant (aluminum hydroxide, which effects the formation and activation of inflammasomes, ensuring the formation and secretion of IL-1β and IL-18 that, in turn, trigger a cascade of cellular and humoral innate immune responses. We demonstrated the possibility of involvement in the induction of innate immunity, mediated by the inactivated vaccine, endogenous pathogenassociated molecular patterns (uric acid and host cell DNA, forming at the vaccine injection site. We discuss the triggering of Band T-cell responses by flavivirus vaccines that determine various duration of protection against various pathogens. A single injection of the live vaccine against yellow fever virus induces polyvalent adaptive immune response, including the production of cytotoxic T-lymphocytes, Th1and Th2-cells and neutralizing antibodies

  6. Oral Antibiotic Treatment of Mice Exacerbates the Disease Severity of Multiple Flavivirus Infections

    Directory of Open Access Journals (Sweden)

    Larissa B. Thackray

    2018-03-01

    Full Text Available Summary: Although the outcome of flavivirus infection can vary from asymptomatic to lethal, environmental factors modulating disease severity are poorly defined. Here, we observed increased susceptibility of mice to severe West Nile (WNV, Dengue, and Zika virus infections after treatment with oral antibiotics (Abx that depleted the gut microbiota. Abx treatment impaired the development of optimal T cell responses, with decreased levels of WNV-specific CD8+ T cells associated with increased infection and immunopathology. Abx treatments that resulted in enhanced WNV susceptibility generated changes in the overall structure of the gut bacterial community and in the abundance of specific bacterial taxa. As little as 3 days of treatment with ampicillin was sufficient to alter host immunity and WNV outcome. Our results identify oral Abx therapy as a potential environmental determinant of systemic viral disease, and they raise the possibility that perturbation of the gut microbiota may have deleterious consequences for subsequent flavivirus infections. : Thackray et al. observed increased susceptibility to West Nile, Zika, and Dengue virus infections following oral antibiotic treatment in mice. Antibiotics altered the bacterial abundance and community structure and the development of optimal T cell immunity. These data suggest that antibiotics may have deleterious consequences for subsequent flavivirus infections. Keywords: West Nile virus, Dengue virus, Zika virus, flavivirus, oral antibiotics, gut microbiota, risk factors, pathogenesis determinants, immunity

  7. Noncoding Subgenomic Flavivirus RNA Is Processed by the Mosquito RNA Interference Machinery and Determines West Nile Virus Transmission by Culex pipiens Mosquitoes

    NARCIS (Netherlands)

    Goertz, G.P.; Fros, J.J.; Miesen, P.; Vogels, C.B.F.; Bent, M.L. van der; Geertsema, C.; Koenraadt, C.J.M.; Rij, R.P. van; Oers, M.M. van; Pijlman, G.P.

    2016-01-01

    Flaviviruses, such as Zika virus, yellow fever virus, dengue virus, and West Nile virus (WNV), are a serious concern for human health. Flaviviruses produce an abundant noncoding subgenomic flavivirus RNA (sfRNA) in infected cells. sfRNA results from stalling of the host 5'-3' exoribonuclease

  8. Hierarchical mixtures of naive Bayes classifiers

    NARCIS (Netherlands)

    Wiering, M.A.

    2002-01-01

    Naive Bayes classifiers tend to perform very well on a large number of problem domains, although their representation power is quite limited compared to more sophisticated machine learning algorithms. In this pa- per we study combining multiple naive Bayes classifiers by using the hierar- chical

  9. Adoptive transfer of natural antibodies to non-immunized chickens affects subsequent antigen-specific humoral and cellular immune responses

    NARCIS (Netherlands)

    Lammers, A.; Klomp, M.E.V.; Nieuwland, M.G.B.; Savelkoul, H.F.J.; Parmentier, H.K.

    2004-01-01

    To determine a regulatory function of natural antibodies in the immune response of chickens, pooled plasma obtained from non-immunized (naive) 15 months old hens was subjected to keyhole limpet hemocyanin (KLH) antigen-affinity chromatography. Purified KLH-binding antibodies were adoptively

  10. Tembusu-like flavivirus (Perak virus) as the cause of neurological disease outbreaks in young Pekin ducks.

    Science.gov (United States)

    Homonnay, Zalán Gábor; Kovács, Edit Walkóné; Bányai, Krisztián; Albert, Mihály; Fehér, Enikő; Mató, Tamás; Tatár-Kis, Tímea; Palya, Vilmos

    2014-01-01

    A neurological disease of young Pekin ducks characterized by ataxia, lameness, and paralysis was observed at several duck farms in Malaysia in 2012. Gross pathological lesions were absent or inconsistent in most of the cases, but severe and consistent microscopic lesions were found in the brain and spinal cord, characterized by non-purulent panencephalomyelitis. Several virus isolates were obtained in embryonated duck eggs and in cell cultures (Vero and DF-1) inoculated with the brain homogenates of affected ducks. After exclusion of other viruses, the isolates were identified as a flavivirus by flavivirus-specific reverse transcription-polymerase chain reaction (RT-PCR) assays. Inoculation of 2-week-old Pekin ducks with a flavivirus isolate by the subcutaneous or intramuscular route resulted in typical clinical signs and histological lesions in the brain and spinal cord. The inoculated virus was detected by RT-PCR from organ samples of ducks with clinical signs and histological lesions. With a few days delay, the disease was also observed among co-mingled contact control birds. Phylogenetic analysis of NS5 and E gene sequences proved that the isolates were representatives of a novel phylogenetic group within clade XI (Ntaya virus group) of the Flavivirus genus. This Malaysian Duck Tembusu Virus (DTMUV), named Perak virus, has moderate genomic RNA sequence similarity to a related DTMUV identified in China. In our experiment the Malaysian strain of DTMUV could be transmitted in the absence of mosquito vectors. These findings may have implications for the control and prevention of this emerging group of flaviviruses.

  11. Correlative scanning-transmission electron microscopy reveals that a chimeric flavivirus is released as individual particles in secretory vesicles.

    Directory of Open Access Journals (Sweden)

    Julien Burlaud-Gaillard

    Full Text Available The intracellular morphogenesis of flaviviruses has been well described, but flavivirus release from the host cell remains poorly documented. We took advantage of the optimized production of an attenuated chimeric yellow fever/dengue virus for vaccine purposes to study this phenomenon by microscopic approaches. Scanning electron microscopy (SEM showed the release of numerous viral particles at the cell surface through a short-lived process. For transmission electron microscopy (TEM studies of the intracellular ultrastructure of the small number of cells releasing viral particles at a given time, we developed a new correlative microscopy method: CSEMTEM (for correlative scanning electron microscopy - transmission electron microscopy. CSEMTEM analysis suggested that chimeric flavivirus particles were released as individual particles, in small exocytosis vesicles, via a regulated secretory pathway. Our morphological findings provide new insight into interactions between flaviviruses and cells and demonstrate that CSEMTEM is a useful new method, complementary to SEM observations of biological events by intracellular TEM investigations.

  12. A trans-Complementing Recombination Trap Demonstrates a Low Propensity of Flaviviruses for Intermolecular Recombination▿

    Science.gov (United States)

    Taucher, Christian; Berger, Angelika; Mandl, Christian W.

    2010-01-01

    Intermolecular recombination between the genomes of closely related RNA viruses can result in the emergence of novel strains with altered pathogenic potential and antigenicity. Although recombination between flavivirus genomes has never been demonstrated experimentally, the potential risk of generating undesirable recombinants has nevertheless been a matter of concern and controversy with respect to the development of live flavivirus vaccines. As an experimental system for investigating the ability of flavivirus genomes to recombine, we developed a “recombination trap,” which was designed to allow the products of rare recombination events to be selected and amplified. To do this, we established reciprocal packaging systems consisting of pairs of self-replicating subgenomic RNAs (replicons) derived from tick-borne encephalitis virus (TBEV), West Nile virus (WNV), and Japanese encephalitis virus (JEV) that could complement each other in trans and thus be propagated together in cell culture over multiple passages. Any infectious viruses with intact, full-length genomes that were generated by recombination of the two replicons would be selected and enriched by end point dilution passage, as was demonstrated in a spiking experiment in which a small amount of wild-type virus was mixed with the packaged replicons. Using the recombination trap and the JEV system, we detected two aberrant recombination events, both of which yielded unnatural genomes containing duplications. Infectious clones of both of these genomes yielded viruses with impaired growth properties. Despite the fact that the replicon pairs shared approximately 600 nucleotides of identical sequence where a precise homologous crossover event would have yielded a wild-type genome, this was not observed in any of these systems, and the TBEV and WNV systems did not yield any viable recombinant genomes at all. Our results show that intergenomic recombination can occur in the structural region of flaviviruses

  13. Safety, efficacy, and biomarkers of nivolumab with vaccine in ipilimumab-refractory or -naive melanoma.

    Science.gov (United States)

    Weber, Jeffrey S; Kudchadkar, Ragini Reiney; Yu, Bin; Gallenstein, Donna; Horak, Christine E; Inzunza, H David; Zhao, Xiuhua; Martinez, Alberto J; Wang, Wenshi; Gibney, Geoffrey; Kroeger, Jodi; Eysmans, Cabell; Sarnaik, Amod A; Chen, Y Ann

    2013-12-01

    Nivolumab, a human immunoglobulin G4-blocking antibody against the T-cell programmed death-1 checkpoint protein, has activity against metastatic melanoma. Its safety, clinical efficacy, and correlative biomarkers were assessed with or without a peptide vaccine in ipilimumab-refractory and -naive melanoma. In this phase I study, 90 patients with unresectable stage III or IV melanoma who were ipilimumab naive and had experienced progression after at least one prior therapy (cohorts 1 to 3, 34 patients) or experienced progression after prior ipilimumab (cohorts 4 to 6, 56 patients) received nivolumab at 1, 3, or 10 mg/kg every 2 weeks for 24 weeks, then every 12 weeks for up to 2 years, with or without a multipeptide vaccine. Nivolumab with vaccine was well tolerated and safe at all doses. The RECIST 1.1 response rate for both ipilimumab-refractory and -naive patients was 25%. Median duration of response was not reached at a median of 8.1 months of follow-up. High pretreatment NY-ESO-1 and MART-1-specific CD8(+) T cells were associated with progression of disease. At week 12, increased peripheral-blood T regulatory cells and decreased antigen-specific T cells were associated with progression. PD-L1 tumor staining was associated with responses to nivolumab, but negative staining did not rule out a response. Patients who experienced progression after nivolumab could respond to ipilimumab. In patients with ipilimumab-refractory or -naive melanoma, nivolumab at 3 mg/kg with or without peptide vaccine was well tolerated and induced responses lasting up to 140 weeks. Responses to nivolumab in ipilimumab-refractory patients or to ipilimumab in nivolumab-refractory patients support combination or sequencing of nivolumab and ipilimumab.

  14. Role of nonstructural protein NS2A in flavivirus assembly

    NARCIS (Netherlands)

    Leung, J.Y.; Pijlman, G.P.; Kondratieva, N.; Hyde, J.; Mackenzie, J.M.; Khromykh, A.A.

    2008-01-01

    Flavivirus nonstructural (NS) proteins are involved in RNA replication and modulation of the host antiviral response; however, evidence is mounting that some NS proteins also have essential roles in virus assembly. Kunjin virus (KUN) NS2A is a small, hydrophobic, transmembrane protein that is part

  15. Applications of recombinant antibodies in plant pathology.

    Science.gov (United States)

    Ziegler, Angelika; Torrance, Lesley

    2002-09-01

    Summary Advances in molecular biology have made it possible to produce antibody fragments comprising the binding domains of antibody molecules in diverse heterologous systems, such as Escherichia coli, insect cells, or plants. Antibody fragments specific for a wide range of antigens, including plant pathogens, have been obtained by cloning V-genes from lymphoid tissue, or by selection from large naive phage display libraries, thus avoiding the need for immunization. The antibody fragments have been expressed as fusion proteins to create different functional molecules, and fully recombinant assays have been devised to detect plant viruses. The defined binding properties and unlimited cheap supply of antibody fusion proteins make them useful components of standardized immunoassays. The expression of antibody fragments in plants was shown to confer resistance to several plant pathogens. However, the antibodies usually only slowed the progress of infection and durable 'plantibody' resistance has yet to be demonstrated. In future, it is anticipated that antibody fragments from large libraries will be essential tools in high-throughput approaches to post-genomics research, such as the assignment of gene function, characterization of spatio-temporal patterns of protein expression, and elucidation of protein-protein interactions.

  16. Systems Analysis Reveals High Genetic and Antigen-Driven Predetermination of Antibody Repertoires throughout B Cell Development

    Directory of Open Access Journals (Sweden)

    Victor Greiff

    2017-05-01

    Full Text Available Antibody repertoire diversity and plasticity is crucial for broad protective immunity. Repertoires change in size and diversity across multiple B cell developmental stages and in response to antigen exposure. However, we still lack fundamental quantitative understanding of the extent to which repertoire diversity is predetermined. Therefore, we implemented a systems immunology framework for quantifying repertoire predetermination on three distinct levels: (1 B cell development (pre-B cell, naive B cell, plasma cell, (2 antigen exposure (three structurally different proteins, and (3 four antibody repertoire components (V-gene usage, clonal expansion, clonal diversity, repertoire size extracted from antibody repertoire sequencing data (400 million reads. Across all three levels, we detected a dynamic balance of high genetic (e.g., >90% for V-gene usage and clonal expansion in naive B cells and antigen-driven (e.g., 40% for clonal diversity in plasma cells predetermination and stochastic variation. Our study has implications for the prediction and manipulation of humoral immunity.

  17. Stability of a Tick-Borne Flavivirus in Milk

    OpenAIRE

    Offerdahl, Danielle K.; Clancy, Niall G.; Bloom, Marshall E.

    2016-01-01

    The tick-borne flaviviruses (TBFV) occur worldwide and the tick-borne encephalitis virus (TBEV) members of the group often cause severe, debilitating neurological disease in humans. Although the primary route of infection is through the bite of an infected tick, alimentary infection through the consumption of TBEV-contaminated dairy products is also well-documented and is responsible for some disease in endemic areas. Experimental infection of goats, cattle, and sheep with TBEV shows that the...

  18. 2′-O Methylation of Internal Adenosine by Flavivirus NS5 Methyltransferase

    Science.gov (United States)

    Dong, Hongping; Chang, David C.; Hua, Maggie Ho Chia; Lim, Siew Pheng; Chionh, Yok Hian; Hia, Fabian; Lee, Yie Hou; Kukkaro, Petra; Lok, Shee-Mei; Dedon, Peter C.; Shi, Pei-Yong

    2012-01-01

    RNA modification plays an important role in modulating host-pathogen interaction. Flavivirus NS5 protein encodes N-7 and 2′-O methyltransferase activities that are required for the formation of 5′ type I cap (m7GpppAm) of viral RNA genome. Here we reported, for the first time, that flavivirus NS5 has a novel internal RNA methylation activity. Recombinant NS5 proteins of West Nile virus and Dengue virus (serotype 4; DENV-4) specifically methylates polyA, but not polyG, polyC, or polyU, indicating that the methylation occurs at adenosine residue. RNAs with internal adenosines substituted with 2′-O-methyladenosines are not active substrates for internal methylation, whereas RNAs with adenosines substituted with N6-methyladenosines can be efficiently methylated, suggesting that the internal methylation occurs at the 2′-OH position of adenosine. Mass spectroscopic analysis further demonstrated that the internal methylation product is 2′-O-methyladenosine. Importantly, genomic RNA purified from DENV virion contains 2′-O-methyladenosine. The 2′-O methylation of internal adenosine does not require specific RNA sequence since recombinant methyltransferase of DENV-4 can efficiently methylate RNAs spanning different regions of viral genome, host ribosomal RNAs, and polyA. Structure-based mutagenesis results indicate that K61-D146-K181-E217 tetrad of DENV-4 methyltransferase forms the active site of internal methylation activity; in addition, distinct residues within the methyl donor (S-adenosyl-L-methionine) pocket, GTP pocket, and RNA-binding site are critical for the internal methylation activity. Functional analysis using flavivirus replicon and genome-length RNAs showed that internal methylation attenuated viral RNA translation and replication. Polymerase assay revealed that internal 2′-O-methyladenosine reduces the efficiency of RNA elongation. Collectively, our results demonstrate that flavivirus NS5 performs 2′-O methylation of internal adenosine of

  19. PENERAPAN ALGORITMA NAIVE BAYES UNTUK MENGKLASIFIKASI DATA NASABAH ASURANSI

    Directory of Open Access Journals (Sweden)

    Bustami Bustami

    2014-01-01

    Full Text Available Data mining adalah teknik yang memanfaatkan data dalam jumlah yang besar untuk memperoleh informasi berharga yang sebelumnya tidak diketahui dan dapat dimanfaatkan untuk pengambilan keputusan penting. Pada penelitian ini, penulis berusaha menambang data (data mining nasabah sebuah perusahaan asuransi untuk mengetahui lancar, kurang lancar atau tidak lancarnya nasabah tersebut. Data yang ada dianalisis menggunakan algoritma Naive Bayes. Naive Bayes merupakan salah satu meode pada probabilistic reasoning. Algoritma Naive Bayes bertujuan untuk melakukan klasifikasi data pada kelas tertentu, kemudian pola tersebut dapat digunakan untuk memperkirakan nasabah yang bergabung, sehingga perusahaan bisa mengambil keputusan menerima atau menolak calon nasabah tersebut. Kata Kunci : data mining, asuransi, klasifikasi, algoritma Naive Bayes

  20. Risk of Erectile Dysfunction in Transfusion-naive Thalassemia Men

    Science.gov (United States)

    Chen, Yu-Guang; Lin, Te-Yu; Lin, Cheng-Li; Dai, Ming-Shen; Ho, Ching-Liang; Kao, Chia-Hung

    2015-01-01

    Abstract Based on the mechanism of pathophysiology, thalassemia major or transfusion-dependent thalassemia patients may have an increased risk of developing organic erectile dysfunction resulting from hypogonadism. However, there have been few studies investigating the association between erectile dysfunction and transfusion-naive thalassemia populations. We constructed a population-based cohort study to elucidate the association between transfusion-naive thalassemia populations and organic erectile dysfunction This nationwide population-based cohort study involved analyzing data from 1998 to 2010 obtained from the Taiwanese National Health Insurance Research Database, with a follow-up period extending to the end of 2011. We identified men with transfusion-naive thalassemia and selected a comparison cohort that was frequency-matched with these according to age, and year of diagnosis thalassemia at a ratio of 1 thalassemia man to 4 control men. We analyzed the risks for transfusion-naive thalassemia men and organic erectile dysfunction by using Cox proportional hazards regression models. In this study, 588 transfusion-naive thalassemia men and 2337 controls were included. Total 12 patients were identified within the thalassaemia group and 10 within the control group. The overall risks for developing organic erectile dysfunction were 4.56-fold in patients with transfusion-naive thalassemia men compared with the comparison cohort after we adjusted for age and comorbidities. Our long-term cohort study results showed that in transfusion-naive thalassemia men, there was a higher risk for the development of organic erectile dysfunction, particularly in those patients with comorbidities. PMID:25837766

  1. Single-domain antibodies that compete with the natural ligand fibroblast growth factor block the internalization of the fibroblast growth factor receptor 1

    Energy Technology Data Exchange (ETDEWEB)

    Veggiani, Gianluca; Ossolengo, Giuseppe; Aliprandi, Marisa; Cavallaro, Ugo [IFOM-IEO Campus, Via Adamello 16, 20139 Milano (Italy); Marco, Ario de, E-mail: ario.demarco@ung.si [IFOM-IEO Campus, Via Adamello 16, 20139 Milano (Italy); Dept. Environmental Sciences, University of Nova Gorica (UNG), Vipavska 13, P.O. Box 301-SI-5000, Rozna Dolina, Nova Gorica (Slovenia)

    2011-05-20

    Highlights: {yields} Recombinant antibodies for FGFR1 were isolated from a llama naive library in VHH format. {yields} These antibodies compete with the natural ligand FGF-2 for the same epitope on FGFR1. {yields} The antibody competition inhibits the FGF-2-dependent internalization of FGFR1. -- Abstract: Single-domain antibodies in VHH format specific for fibroblast growth factor receptor 1 (FGFR1) were isolated from a phage-display llama naive library. In particular, phage elution in the presence of the natural receptor ligand fibroblast growth factor (FGF) allowed for the identification of recombinant antibodies that compete with FGF for the same region on the receptor surface. These antibodies posses a relatively low affinity for FGFR1 and were never identified when unspecific elution conditions favoring highly affine binders were applied to panning procedures. Two populations of competitive antibodies were identified that labeled specifically the receptor-expressing cells in immunofluorescence and recognize distinct epitopes. Antibodies from both populations effectively prevented FGF-dependent internalization and nuclear accumulation of the receptor in cultured cells. This achievement indicates that these antibodies have a capacity to modulate the receptor physiology and, therefore, constitute powerful reagents for basic research and a potential lead for therapeutic applications.

  2. Single-domain antibodies that compete with the natural ligand fibroblast growth factor block the internalization of the fibroblast growth factor receptor 1

    International Nuclear Information System (INIS)

    Veggiani, Gianluca; Ossolengo, Giuseppe; Aliprandi, Marisa; Cavallaro, Ugo; Marco, Ario de

    2011-01-01

    Highlights: → Recombinant antibodies for FGFR1 were isolated from a llama naive library in VHH format. → These antibodies compete with the natural ligand FGF-2 for the same epitope on FGFR1. → The antibody competition inhibits the FGF-2-dependent internalization of FGFR1. -- Abstract: Single-domain antibodies in VHH format specific for fibroblast growth factor receptor 1 (FGFR1) were isolated from a phage-display llama naive library. In particular, phage elution in the presence of the natural receptor ligand fibroblast growth factor (FGF) allowed for the identification of recombinant antibodies that compete with FGF for the same region on the receptor surface. These antibodies posses a relatively low affinity for FGFR1 and were never identified when unspecific elution conditions favoring highly affine binders were applied to panning procedures. Two populations of competitive antibodies were identified that labeled specifically the receptor-expressing cells in immunofluorescence and recognize distinct epitopes. Antibodies from both populations effectively prevented FGF-dependent internalization and nuclear accumulation of the receptor in cultured cells. This achievement indicates that these antibodies have a capacity to modulate the receptor physiology and, therefore, constitute powerful reagents for basic research and a potential lead for therapeutic applications.

  3. Noncoding Subgenomic Flavivirus RNA Is Processed by the Mosquito RNA Interference Machinery and Determines West Nile Virus Transmission by Culex pipiens Mosquitoes.

    Science.gov (United States)

    Göertz, G P; Fros, J J; Miesen, P; Vogels, C B F; van der Bent, M L; Geertsema, C; Koenraadt, C J M; van Rij, R P; van Oers, M M; Pijlman, G P

    2016-11-15

    Flaviviruses, such as Zika virus, yellow fever virus, dengue virus, and West Nile virus (WNV), are a serious concern for human health. Flaviviruses produce an abundant noncoding subgenomic flavivirus RNA (sfRNA) in infected cells. sfRNA results from stalling of the host 5'-3' exoribonuclease XRN1/Pacman on conserved RNA structures in the 3' untranslated region (UTR) of the viral genomic RNA. sfRNA production is conserved in insect-specific, mosquito-borne, and tick-borne flaviviruses and flaviviruses with no known vector, suggesting a pivotal role for sfRNA in the flavivirus life cycle. Here, we investigated the function of sfRNA during WNV infection of Culex pipiens mosquitoes and evaluated its role in determining vector competence. An sfRNA1-deficient WNV was generated that displayed growth kinetics similar to those of wild-type WNV in both RNA interference (RNAi)-competent and -compromised mosquito cell lines. Small-RNA deep sequencing of WNV-infected mosquitoes indicated an active small interfering RNA (siRNA)-based antiviral response for both the wild-type and sfRNA1-deficient viruses. Additionally, we provide the first evidence that sfRNA is an RNAi substrate in vivo Two reproducible small-RNA hot spots within the 3' UTR/sfRNA of the wild-type virus mapped to RNA stem-loops SL-III and 3' SL, which stick out of the three-dimensional (3D) sfRNA structure model. Importantly, we demonstrate that sfRNA-deficient WNV displays significantly decreased infection and transmission rates in vivo when administered via the blood meal. Finally, we show that transmission and infection rates are not affected by sfRNA after intrathoracic injection, thereby identifying sfRNA as a key driver to overcome the mosquito midgut infection barrier. This is the first report to describe a key biological function of sfRNA for flavivirus infection of the arthropod vector, providing an explanation for the strict conservation of sfRNA production. Understanding the flavivirus transmission

  4. Sophisticating a naive Liapunov function

    International Nuclear Information System (INIS)

    Smith, D.; Lewins, J.D.

    1985-01-01

    The art of the direct method of Liapunov to determine system stability is to construct a suitable Liapunov or V function where V is to be positive definite (PD), to shrink to a center, which may be conveniently chosen as the origin, and where V is the negative definite (ND). One aid to the art is to solve an approximation to the system equations in order to provide a candidate V function. It can happen, however, that the V function is not strictly ND but vanishes at a finite number of isolated points. Naively, one anticipates that stability has been demonstrated since the trajectory of the system at such points is only momentarily tangential and immediately enters a region of inward directed trajectories. To demonstrate stability rigorously requires the construction of a sophisticated Liapunov function from what can be called the naive original choice. In this paper, the authors demonstrate the method of perturbing the naive function in the context of the well-known second-order oscillator and then apply the method to a more complicated problem based on a prompt jump model for a nuclear fission reactor

  5. Antibody phage display applications for nuclear medicine imaging and therapy

    International Nuclear Information System (INIS)

    Winthrop, M.D.; Denardo, G.L.; Denardo, S.J.

    2000-01-01

    Antibody-based constructs genetically engineered from genes of diverse origin provide a remarkable opportunity to develop functional molecular imaging techniques and specific molecular targeted radionuclide therapies. Phage display libraries of antibody fragment genes can be used to select antibody-based constructs that bind any chosen epitope. A large naive human antibody-based library was used to illustrate binding of antibody constructs to a variety of common and unique antigens. Antibody-based libraries from hybridoma cells, lymphocytes from immunized humans or from mice and human antibody repertoires produced in transgenic mice have also been described. Several orders of magnitude of affinity enhancement can be achieved by random or site specific mutations of the selected binding peptide domains of the scFv. Affinities (K d ) as high as 10 - 11 M (10 pM) for affinity-matured scFv have been documented. Such gene libraries thus offer an almost limitless variety of antibody-based molecular binding peptide modules that can be used in creative ways for the construction of new targeting agents for functional or molecular imaging and therapy

  6. Rapid Identification of Vector-Borne Flaviviruses by Mass Spectrometry

    Science.gov (United States)

    2010-02-01

    Eastern, and Siberian subtypes [9]. Several tick-borne flaviviruses can also cause hemorrhagic disease. Important examples of these viruses include...assay. Identical base compositions within a column are the same color. Unique base compositions are shown with white backgrounds. (For interpretation...States, 1999e2005. Vector Borne Zoonotic Dis 2008;8:733e40. [18] Hofstadler SA, Sampath R, Blyn LB, Eshoo MW, Hall TA, Jiang Y, et al. TIGER : the

  7. A Public Database of Memory and Naive B-Cell Receptor Sequences.

    Directory of Open Access Journals (Sweden)

    William S DeWitt

    Full Text Available The vast diversity of B-cell receptors (BCR and secreted antibodies enables the recognition of, and response to, a wide range of epitopes, but this diversity has also limited our understanding of humoral immunity. We present a public database of more than 37 million unique BCR sequences from three healthy adult donors that is many fold deeper than any existing resource, together with a set of online tools designed to facilitate the visualization and analysis of the annotated data. We estimate the clonal diversity of the naive and memory B-cell repertoires of healthy individuals, and provide a set of examples that illustrate the utility of the database, including several views of the basic properties of immunoglobulin heavy chain sequences, such as rearrangement length, subunit usage, and somatic hypermutation positions and dynamics.

  8. A Public Database of Memory and Naive B-Cell Receptor Sequences.

    Science.gov (United States)

    DeWitt, William S; Lindau, Paul; Snyder, Thomas M; Sherwood, Anna M; Vignali, Marissa; Carlson, Christopher S; Greenberg, Philip D; Duerkopp, Natalie; Emerson, Ryan O; Robins, Harlan S

    2016-01-01

    The vast diversity of B-cell receptors (BCR) and secreted antibodies enables the recognition of, and response to, a wide range of epitopes, but this diversity has also limited our understanding of humoral immunity. We present a public database of more than 37 million unique BCR sequences from three healthy adult donors that is many fold deeper than any existing resource, together with a set of online tools designed to facilitate the visualization and analysis of the annotated data. We estimate the clonal diversity of the naive and memory B-cell repertoires of healthy individuals, and provide a set of examples that illustrate the utility of the database, including several views of the basic properties of immunoglobulin heavy chain sequences, such as rearrangement length, subunit usage, and somatic hypermutation positions and dynamics.

  9. Selection of phage-displayed accessible recombinant targeted antibodies (SPARTA): methodology and applications.

    Science.gov (United States)

    D'Angelo, Sara; Staquicini, Fernanda I; Ferrara, Fortunato; Staquicini, Daniela I; Sharma, Geetanjali; Tarleton, Christy A; Nguyen, Huynh; Naranjo, Leslie A; Sidman, Richard L; Arap, Wadih; Bradbury, Andrew Rm; Pasqualini, Renata

    2018-05-03

    We developed a potentially novel and robust antibody discovery methodology, termed selection of phage-displayed accessible recombinant targeted antibodies (SPARTA). This combines an in vitro screening step of a naive human antibody library against known tumor targets, with in vivo selections based on tumor-homing capabilities of a preenriched antibody pool. This unique approach overcomes several rate-limiting challenges to generate human antibodies amenable to rapid translation into medical applications. As a proof of concept, we evaluated SPARTA on 2 well-established tumor cell surface targets, EphA5 and GRP78. We evaluated antibodies that showed tumor-targeting selectivity as a representative panel of antibody-drug conjugates (ADCs) and were highly efficacious. Our results validate a discovery platform to identify and validate monoclonal antibodies with favorable tumor-targeting attributes. This approach may also extend to other diseases with known cell surface targets and affected tissues easily isolated for in vivo selection.

  10. Selection of diethylstilbestrol-specific single-chain antibodies from a non-immunized mouse ribosome display library.

    Directory of Open Access Journals (Sweden)

    Yanan Sun

    Full Text Available Single chain variable fragments (scFvs against diethylstilbestrol (DES were selected from the splenocytes of non-immunized mice by ribosome display technology. A naive library was constructed and engineered to allow in vitro transcription and translation using an E. coli lysate system. Alternating selection in solution and immobilization in microtiter wells was used to pan mRNA-ribosome-antibody (ARM complexes. After seven rounds of ribosome display, the expression vector pTIG-TRX containing the selected specific scFv DNAs were transformed into Escherichia coli BL21 (DE3 for expression. Twenty-six positive clones were screened and five clones had high antibody affinity and specificity to DES as evidenced by indirect competitive ELISA. Sequence analysis showed that these five DES-specific scFvs had different amino acid sequences, but the CDRs were highly similar. Surface plasmon resonance (SPR analysis was used to determine binding kinetics of one clone (30-1. The measured K(D was 3.79 µM. These results indicate that ribosome display technology can be used to efficiently isolate hapten-specific antibody (Ab fragments from a naive library; this study provides a methodological framework for the development of novel immunoassays for multiple environmental pollutants with low molecular weight detection using recombinant antibodies.

  11. Zoonotic encephalitides caused by arboviruses: transmission and epidemiology of alphaviruses and flaviviruses.

    Science.gov (United States)

    Go, Yun Young; Balasuriya, Udeni B R; Lee, Chong-Kyo

    2014-01-01

    In this review, we mainly focus on zoonotic encephalitides caused by arthropod-borne viruses (arboviruses) of the families Flaviviridae (genus Flavivirus) and Togaviridae (genus Alphavirus) that are important in both humans and domestic animals. Specifically, we will focus on alphaviruses (Eastern equine encephalitis virus, Western equine encephalitis virus, Venezuelan equine encephalitis virus) and flaviviruses (Japanese encephalitis virus and West Nile virus). Most of these viruses were originally found in tropical regions such as Africa and South America or in some regions in Asia. However, they have dispersed widely and currently cause diseases around the world. Global warming, increasing urbanization and population size in tropical regions, faster transportation and rapid spread of arthropod vectors contribute in continuous spreading of arboviruses into new geographic areas causing reemerging or resurging diseases. Most of the reemerging arboviruses also have emerged as zoonotic disease agents and created major public health issues and disease epidemics.

  12. The pH sensor for flavivirus membrane fusion

    OpenAIRE

    Harrison, Stephen C.

    2008-01-01

    Viruses that infect cells by uptake through endosomes have generally evolved to ?sense? the local pH as part of the mechanism by which they penetrate into the cytosol. Even for the very well studied fusion proteins of enveloped viruses, identification of the specific pH sensor has been a challenge, one that has now been met successfully, for flaviviruses, by Fritz et al. (Fritz, R., K. Stiasny, and F.X. Heinz. 2008. J. Cell Biol. 183:353?361) in this issue. Thorough mutational analysis of con...

  13. Mice with different susceptibility to tick-borne encephalitis virus infection show selective neutralizing antibody response and inflammatory reaction in the central nervous system

    Czech Academy of Sciences Publication Activity Database

    Palus, Martin; Vojtíšková, Jarmila; Salát, Jiří; Kopecký, Jan; Grubhoffer, Libor; Lipoldová, Marie; Demant, P.; Růžek, Daniel

    2013-01-01

    Roč. 10, JUN 2013 (2013), s. 77 E-ISSN 1742-2094 R&D Projects: GA ČR GAP502/11/2116 Grant - others:GA MŠk(CZ) ED0006/01/01 Institutional support: RVO:60077344 ; RVO:68378050 Keywords : Tick-borne encephalitis * Flavivirus encephalitis * Neuroinflammation * Antibody production Subject RIV: EC - Immunology; EB - Genetics ; Molecular Biology (UMG-J) Impact factor: 4.902, year: 2013

  14. Molecular archaeology of Flaviviridae untranslated regions: duplicated RNA structures in the replication enhancer of flaviviruses and pestiviruses emerged via convergent evolution.

    Directory of Open Access Journals (Sweden)

    Dmitri J Gritsun

    Full Text Available RNA secondary structures in the 3'untranslated regions (3'UTR of the viruses of the family Flaviviridae, previously identified as essential (promoters or beneficial (enhancers for replication, have been analysed. Duplicated enhancer elements are revealed as a global feature in the evolution of the 3'UTR of distantly related viruses within the genera Flavivirus and Pestivirus. For the flaviviruses, duplicated structures occur in the 3'UTR of all four distantly related ecological virus subgroups (tick-borne, mosquito-borne, no known vector and insect-specific flaviviruses (ISFV. RNA structural differences distinguish tick-borne flaviviruses with discrete pathogenetic characteristics. For Aedes- and Culex-associated ISFV, secondary RNA structures with different conformations display numerous short ssRNA direct repeats, exposed as loops and bulges. Long quadruplicate regions comprise almost the entire 3'UTR of Culex-associated ISFV. Extended duplicated sequence and associated RNA structures were also discovered in the 3'UTR of pestiviruses. In both the Flavivirus and Pestivirus genera, duplicated RNA structures were localized to the enhancer regions of the 3'UTR suggesting an adaptive role predominantly in wild-type viruses. We propose sequence reiteration might act as a scaffold for dimerization of proteins involved in assembly of viral replicase complexes. Numerous nucleotide repeats exposed as loops/bulges might also interfere with host immune responses acting as a molecular sponge to sequester key host proteins or microRNAs.

  15. Yugoslav Naive Art and Popular Culture

    Directory of Open Access Journals (Sweden)

    Meta Kordiš

    2009-12-01

    After the Second World War, the Yugoslav socialist state also strove to equalize and democratize society through art by minimizing the differences between the producers and consumers of art. Such a policy led to the decentralization of culture by forming various cultural and artistic institutions and by holding cultural events and spectacles in the countryside and peripheral areas. Through these various informal ideological mechanisms, the state apparatus exercised its authority in socializing its people in the spirit of Yugoslav socialist self-management and the ideology of brotherhood and unity by joining together the producers and consumers of naive art from various ethnicities, cultures, and social classes. Unfortunately this transformed naive art at its peak of popularity into a decorative and souvenir artifact with a pastoral image and folklore motifs. The encouragement from the authorities on the one hand and the market on the other produced and reproduced simple art forms and narrative contents without a complex iconography, which were consumed uncritically and on a large scale. Consequently, this completely denied the core of naive art and resulted in its final devaluation.

  16. Antibody responses of ponies to initial and challenge infections of Strongylus vulgaris.

    Science.gov (United States)

    Klei, T R; Chapman, M R; Torbert, B J; McClure, J R

    1983-05-01

    An indirect fluorescent antibody assay (IFA) was developed using Strongylus vulgaris third stage larvae (L3) as antigens. Observations using the IFA indicate that a species-specific antibody response to S. vulgaris L3 develops in S. vulgaris-infected ponies and that some surface L3 antigens are shared by adult worms. Sequential antibody levels against S. vulgaris were measured in strongyle-naive and in immune ponies following initial and challenge infections using the IFA and an indirect hemagglutination assay (IHA). Antibody levels measured by IFA increased faster following initial infections than did levels measured by IHA. Antibody levels appear to increase following challenge infections of immune ponies when measured with the IFA, but not with the IHA. Significant differences in antibody titers were not seen between ponies which developed colic following challenge infections and those that did not develop colic. Antibodies were not detectable in ponies unexposed to larval migrations, but which received surgical implantation of S. vulgaris adults into the cecum.

  17. A three-dimensional comparison of tick-borne flavivirus infection in mammalian and tick cell lines.

    Directory of Open Access Journals (Sweden)

    Danielle K Offerdahl

    Full Text Available Tick-borne flaviviruses (TBFV are sustained in nature through cycling between mammalian and tick hosts. In this study, we used African green monkey kidney cells (Vero and Ixodes scapularis tick cells (ISE6 to compare virus-induced changes in mammalian and arthropod cells. Using confocal microscopy, transmission electron microscopy (TEM, and electron tomography (ET, we examined viral protein distribution and the ultrastructural changes that occur during TBFV infection. Within host cells, flaviviruses cause complex rearrangement of cellular membranes for the purpose of virus replication. Virus infection was accompanied by a marked expansion in endoplasmic reticulum (ER staining and markers for TBFV replication were localized mainly to the ER in both cell lines. TEM of Vero cells showed membrane-bound vesicles enclosed in a network of dilated, anastomosing ER cisternae. Virions were seen within the ER and were sometimes in paracrystalline arrays. Tubular structures or elongated vesicles were occasionally noted. In acutely and persistently infected ISE6 cells, membrane proliferation and vesicles were also noted; however, the extent of membrane expansion and the abundance of vesicles were lower and no viral particles were observed. Tubular profiles were far more prevalent in persistently infected ISE6 cells than in acutely infected cells. By ET, tubular profiles, in persistently infected tick cells, had a cross-sectional diameter of 60-100 nm, reached up to 800 nm in length, were closed at the ends, and were often arranged in fascicle-like bundles, shrouded with ER membrane. Our experiments provide analysis of viral protein localization within the context of both mammalian and arthropod cell lines as well as both acute and persistent arthropod cell infection. Additionally, we show for the first time 3D flavivirus infection in a vector cell line and the first ET of persistent flavivirus infection.

  18. Búsqueda de flavivirus en mosquitos de humedales españoles: análisis moleculares del virus west nile y otros flavivirus

    OpenAIRE

    Vázquez González, Ana

    2011-01-01

    Teniendo en cuenta la importancia de los flavivirus en salud humana, la gran actividad y expansión del virus West Nile en los últimos años y los antecedentes serológicos que evidencian la presencia de estos virus en nuestro país, esta tesis doctoral se ha basado en el estudio de la presencia de estos virus, en su caracterización molecular y filogenética y en el desarrollo de nueva metodología para su diagnóstico. Por ello nos planteamos tres objetivos principales. En primer lug...

  19. Molecular Archaeology of Flaviviridae Untranslated Regions: Duplicated RNA Structures in the Replication Enhancer of Flaviviruses and Pestiviruses Emerged via Convergent Evolution

    Science.gov (United States)

    Gritsun, Dmitri J.; Jones, Ian M.; Gould, Ernest A.; Gritsun, Tamara S.

    2014-01-01

    RNA secondary structures in the 3′untranslated regions (3′UTR) of the viruses of the family Flaviviridae, previously identified as essential (promoters) or beneficial (enhancers) for replication, have been analysed. Duplicated enhancer elements are revealed as a global feature in the evolution of the 3′UTR of distantly related viruses within the genera Flavivirus and Pestivirus. For the flaviviruses, duplicated structures occur in the 3′UTR of all four distantly related ecological virus subgroups (tick-borne, mosquito-borne, no known vector and insect-specific flaviviruses (ISFV). RNA structural differences distinguish tick-borne flaviviruses with discrete pathogenetic characteristics. For Aedes- and Culex-associated ISFV, secondary RNA structures with different conformations display numerous short ssRNA direct repeats, exposed as loops and bulges. Long quadruplicate regions comprise almost the entire 3′UTR of Culex-associated ISFV. Extended duplicated sequence and associated RNA structures were also discovered in the 3′UTR of pestiviruses. In both the Flavivirus and Pestivirus genera, duplicated RNA structures were localized to the enhancer regions of the 3′UTR suggesting an adaptive role predominantly in wild-type viruses. We propose sequence reiteration might act as a scaffold for dimerization of proteins involved in assembly of viral replicase complexes. Numerous nucleotide repeats exposed as loops/bulges might also interfere with host immune responses acting as a molecular sponge to sequester key host proteins or microRNAs. PMID:24647143

  20. Derivation of novel human ground state naive pluripotent stem cells.

    Science.gov (United States)

    Gafni, Ohad; Weinberger, Leehee; Mansour, Abed AlFatah; Manor, Yair S; Chomsky, Elad; Ben-Yosef, Dalit; Kalma, Yael; Viukov, Sergey; Maza, Itay; Zviran, Asaf; Rais, Yoach; Shipony, Zohar; Mukamel, Zohar; Krupalnik, Vladislav; Zerbib, Mirie; Geula, Shay; Caspi, Inbal; Schneir, Dan; Shwartz, Tamar; Gilad, Shlomit; Amann-Zalcenstein, Daniela; Benjamin, Sima; Amit, Ido; Tanay, Amos; Massarwa, Rada; Novershtern, Noa; Hanna, Jacob H

    2013-12-12

    Mouse embryonic stem (ES) cells are isolated from the inner cell mass of blastocysts, and can be preserved in vitro in a naive inner-cell-mass-like configuration by providing exogenous stimulation with leukaemia inhibitory factor (LIF) and small molecule inhibition of ERK1/ERK2 and GSK3β signalling (termed 2i/LIF conditions). Hallmarks of naive pluripotency include driving Oct4 (also known as Pou5f1) transcription by its distal enhancer, retaining a pre-inactivation X chromosome state, and global reduction in DNA methylation and in H3K27me3 repressive chromatin mark deposition on developmental regulatory gene promoters. Upon withdrawal of 2i/LIF, naive mouse ES cells can drift towards a primed pluripotent state resembling that of the post-implantation epiblast. Although human ES cells share several molecular features with naive mouse ES cells, they also share a variety of epigenetic properties with primed murine epiblast stem cells (EpiSCs). These include predominant use of the proximal enhancer element to maintain OCT4 expression, pronounced tendency for X chromosome inactivation in most female human ES cells, increase in DNA methylation and prominent deposition of H3K27me3 and bivalent domain acquisition on lineage regulatory genes. The feasibility of establishing human ground state naive pluripotency in vitro with equivalent molecular and functional features to those characterized in mouse ES cells remains to be defined. Here we establish defined conditions that facilitate the derivation of genetically unmodified human naive pluripotent stem cells from already established primed human ES cells, from somatic cells through induced pluripotent stem (iPS) cell reprogramming or directly from blastocysts. The novel naive pluripotent cells validated herein retain molecular characteristics and functional properties that are highly similar to mouse naive ES cells, and distinct from conventional primed human pluripotent cells. This includes competence in the generation

  1. Characterization of a structural intermediate of flavivirus membrane fusion.

    Directory of Open Access Journals (Sweden)

    Karin Stiasny

    2007-02-01

    Full Text Available Viral membrane fusion proceeds through a sequence of steps that are driven by triggered conformational changes of viral envelope glycoproteins, so-called fusion proteins. Although high-resolution structural snapshots of viral fusion proteins in their prefusion and postfusion conformations are available, it has been difficult to define intermediate structures of the fusion pathway because of their transient nature. Flaviviruses possess a class II viral fusion protein (E mediating fusion at acidic pH that is converted from a dimer to a trimer with a hairpin-like structure during the fusion process. Here we show for tick-borne encephalitis virus that exposure of virions to alkaline instead of acidic pH traps the particles in an intermediate conformation in which the E dimers dissociate and interact with target membranes via the fusion peptide without proceeding to the merger of the membranes. Further treatment to low pH, however, leads to fusion, suggesting that these monomers correspond to an as-yet-elusive intermediate required to convert the prefusion dimer into the postfusion trimer. Thus, the use of nonphysiological conditions allows a dissection of the flavivirus fusion process and the identification of two separate steps, in which membrane insertion of multiple copies of E monomers precedes the formation of hairpin-like trimers. This sequence of events provides important new insights for understanding the dynamic process of viral membrane fusion.

  2. Smoothness without smoothing: why Gaussian naive Bayes is not naive for multi-subject searchlight studies.

    Directory of Open Access Journals (Sweden)

    Rajeev D S Raizada

    Full Text Available Spatial smoothness is helpful when averaging fMRI signals across multiple subjects, as it allows different subjects' corresponding brain areas to be pooled together even if they are slightly misaligned. However, smoothing is usually not applied when performing multivoxel pattern-based analyses (MVPA, as it runs the risk of blurring away the information that fine-grained spatial patterns contain. It would therefore be desirable, if possible, to carry out pattern-based analyses which take unsmoothed data as their input but which produce smooth images as output. We show here that the Gaussian Naive Bayes (GNB classifier does precisely this, when it is used in "searchlight" pattern-based analyses. We explain why this occurs, and illustrate the effect in real fMRI data. Moreover, we show that analyses using GNBs produce results at the multi-subject level which are statistically robust, neurally plausible, and which replicate across two independent data sets. By contrast, SVM classifiers applied to the same data do not generate a replication, even if the SVM-derived searchlight maps have smoothing applied to them. An additional advantage of GNB classifiers for searchlight analyses is that they are orders of magnitude faster to compute than more complex alternatives such as SVMs. Collectively, these results suggest that Gaussian Naive Bayes classifiers may be a highly non-naive choice for multi-subject pattern-based fMRI studies.

  3. Flavivirus infection from mosquitoes in vitro reveals cell entry at the plasma membrane

    International Nuclear Information System (INIS)

    Vancini, Ricardo; Kramer, Laura D.; Ribeiro, Mariana; Hernandez, Raquel; Brown, Dennis

    2013-01-01

    Dengue and West Nile viruses are enveloped RNA viruses that belong to genus Flavivirus (family Flaviviridae) and are considered important mosquito-borne viral pathogenic agents worldwide. A potential target for intervention strategies is the virus cell entry mechanism. Previous studies of flavivirus entry have focused on the effects of biochemical and molecular inhibitors on viral entry leading to controversial conclusions suggesting that the process is dependent upon endocytosis and low pH mediated membrane fusion. In this study we analyzed the early events in the infection process by means of electron microscopy and immuno-gold labeling of viral particles during cell entry, and used as a new approach for infecting cells with viruses obtained directly from mosquitoes. The results show that Dengue and West Nile viruses may infect cells by a mechanism that involves direct penetration of the host cell plasma membrane as proposed for alphaviruses.

  4. Flavivirus infection from mosquitoes in vitro reveals cell entry at the plasma membrane

    Energy Technology Data Exchange (ETDEWEB)

    Vancini, Ricardo [Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC (United States); Kramer, Laura D. [Wadsworth Center, New York State Department of Health, and School of Public Health, State University of New York at Albany, Albany, NY (United States); Ribeiro, Mariana; Hernandez, Raquel [Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC (United States); Brown, Dennis, E-mail: dennis_brown@ncsu.edu [Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC (United States)

    2013-01-20

    Dengue and West Nile viruses are enveloped RNA viruses that belong to genus Flavivirus (family Flaviviridae) and are considered important mosquito-borne viral pathogenic agents worldwide. A potential target for intervention strategies is the virus cell entry mechanism. Previous studies of flavivirus entry have focused on the effects of biochemical and molecular inhibitors on viral entry leading to controversial conclusions suggesting that the process is dependent upon endocytosis and low pH mediated membrane fusion. In this study we analyzed the early events in the infection process by means of electron microscopy and immuno-gold labeling of viral particles during cell entry, and used as a new approach for infecting cells with viruses obtained directly from mosquitoes. The results show that Dengue and West Nile viruses may infect cells by a mechanism that involves direct penetration of the host cell plasma membrane as proposed for alphaviruses.

  5. Primate-specific endogenous retrovirus-driven transcription defines naive-like stem cells.

    Science.gov (United States)

    Wang, Jichang; Xie, Gangcai; Singh, Manvendra; Ghanbarian, Avazeh T; Raskó, Tamás; Szvetnik, Attila; Cai, Huiqiang; Besser, Daniel; Prigione, Alessandro; Fuchs, Nina V; Schumann, Gerald G; Chen, Wei; Lorincz, Matthew C; Ivics, Zoltán; Hurst, Laurence D; Izsvák, Zsuzsanna

    2014-12-18

    Naive embryonic stem cells hold great promise for research and therapeutics as they have broad and robust developmental potential. While such cells are readily derived from mouse blastocysts it has not been possible to isolate human equivalents easily, although human naive-like cells have been artificially generated (rather than extracted) by coercion of human primed embryonic stem cells by modifying culture conditions or through transgenic modification. Here we show that a sub-population within cultures of human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) manifests key properties of naive state cells. These naive-like cells can be genetically tagged, and are associated with elevated transcription of HERVH, a primate-specific endogenous retrovirus. HERVH elements provide functional binding sites for a combination of naive pluripotency transcription factors, including LBP9, recently recognized as relevant to naivety in mice. LBP9-HERVH drives hESC-specific alternative and chimaeric transcripts, including pluripotency-modulating long non-coding RNAs. Disruption of LBP9, HERVH and HERVH-derived transcripts compromises self-renewal. These observations define HERVH expression as a hallmark of naive-like hESCs, and establish novel primate-specific transcriptional circuitry regulating pluripotency.

  6. Visualizing non infectious and infectious Anopheles gambiae blood feedings in naive and saliva-immunized mice.

    Directory of Open Access Journals (Sweden)

    Valerie Choumet

    Full Text Available BACKGROUND: Anopheles gambiae is a major vector of malaria and lymphatic filariasis. The arthropod-host interactions occurring at the skin interface are complex and dynamic. We used a global approach to describe the interaction between the mosquito (infected or uninfected and the skin of mammals during blood feeding. METHODS: Intravital video microscopy was used to characterize several features during blood feeding. The deposition and movement of Plasmodium berghei sporozoites in the dermis were also observed. We also used histological techniques to analyze the impact of infected and uninfected feedings on the skin cell response in naive mice. RESULTS: The mouthparts were highly mobile within the skin during the probing phase. Probing time increased with mosquito age, with possible effects on pathogen transmission. Repletion was achieved by capillary feeding. The presence of sporozoites in the salivary glands modified the behavior of the mosquitoes, with infected females tending to probe more than uninfected females (86% versus 44%. A white area around the tip of the proboscis was observed when the mosquitoes fed on blood from the vessels of mice immunized with saliva. Mosquito feedings elicited an acute inflammatory response in naive mice that peaked three hours after the bite. Polynuclear and mast cells were associated with saliva deposits. We describe the first visualization of saliva in the skin by immunohistochemistry (IHC with antibodies directed against saliva. Both saliva deposits and sporozoites were detected in the skin for up to 18 h after the bite. CONCLUSION: This study, in which we visualized the probing and engorgement phases of Anopheles gambiae blood meals, provides precise information about the behavior of the insect as a function of its infection status and the presence or absence of anti-saliva antibodies. It also provides insight into the possible consequences of the inflammatory reaction for blood feeding and pathogen

  7. Visualizing non infectious and infectious Anopheles gambiae blood feedings in naive and saliva-immunized mice.

    Science.gov (United States)

    Choumet, Valerie; Attout, Tarik; Chartier, Loïc; Khun, Huot; Sautereau, Jean; Robbe-Vincent, Annie; Brey, Paul; Huerre, Michel; Bain, Odile

    2012-01-01

    Anopheles gambiae is a major vector of malaria and lymphatic filariasis. The arthropod-host interactions occurring at the skin interface are complex and dynamic. We used a global approach to describe the interaction between the mosquito (infected or uninfected) and the skin of mammals during blood feeding. Intravital video microscopy was used to characterize several features during blood feeding. The deposition and movement of Plasmodium berghei sporozoites in the dermis were also observed. We also used histological techniques to analyze the impact of infected and uninfected feedings on the skin cell response in naive mice. The mouthparts were highly mobile within the skin during the probing phase. Probing time increased with mosquito age, with possible effects on pathogen transmission. Repletion was achieved by capillary feeding. The presence of sporozoites in the salivary glands modified the behavior of the mosquitoes, with infected females tending to probe more than uninfected females (86% versus 44%). A white area around the tip of the proboscis was observed when the mosquitoes fed on blood from the vessels of mice immunized with saliva. Mosquito feedings elicited an acute inflammatory response in naive mice that peaked three hours after the bite. Polynuclear and mast cells were associated with saliva deposits. We describe the first visualization of saliva in the skin by immunohistochemistry (IHC) with antibodies directed against saliva. Both saliva deposits and sporozoites were detected in the skin for up to 18 h after the bite. This study, in which we visualized the probing and engorgement phases of Anopheles gambiae blood meals, provides precise information about the behavior of the insect as a function of its infection status and the presence or absence of anti-saliva antibodies. It also provides insight into the possible consequences of the inflammatory reaction for blood feeding and pathogen transmission.

  8. The Malaria Vaccine Candidate GMZ2 Elicits Functional Antibodies in Individuals From Malaria Endemic and Non-Endemic Areas

    DEFF Research Database (Denmark)

    Jepsen, Micha Phill Grønholm; Jogdand, Prajakta S; Singh, Susheel K

    2013-01-01

    against Plasmodium falciparum. Results. We showed that the maximum level of immunoglobulin G (IgG) antibodies obtained by GMZ2 vaccination is independent of ethnicity, time under malaria-exposure, and vaccine dose and that GMZ2 elicits high levels of functionally active IgG antibodies. Both, malaria......-naive adults and malaria-exposed preschool children elicit vaccine-specific antibodies with broad inhibitory activity against geographically diverse P. falciparum isolates. Peptide-mapping studies of IgG subclass responses identified IgG3 against a peptide derived from MSP3 as the strongest predictor...

  9. File list: Oth.Bld.10.AllAg.Naive_T_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

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  11. File list: ALL.Bld.10.AllAg.Naive_T_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  12. File list: ALL.Bld.50.AllAg.Naive_T_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  13. File list: ALL.Bld.05.AllAg.Naive_T_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  14. ANTIGENIC RELATEDNESS OF SELECTED FLAVIVIRUSES: STUDY WITH HOMOLOGOUS AND HETEROLOGOUS IMMUNE MOUSE ASCITIC FLUIDS

    Directory of Open Access Journals (Sweden)

    S.S. BABA

    1998-11-01

    Full Text Available The antigenic relationship of 9 flaviviruses, Yellow fever (YF , Wesselsbron (WSL , Uganda S (UGS , Potiskum (POT, West Nile (WN , Banzi (BAN , Zika (ZK , Dengue type 1 (DEN-1 and Dengue type 2 (DEN-2, was assessed by cross-haemagglutination-inhibition (Cross-HI and cross-complement fixation (Cross-CF reactions between each of the viruses and their homologous immune mouse ascitic fluids. Titre ratios were calculated using the heterologous and homologous titres. Cross-CF reactions revealed wider antigenic variations among viruses than Cross-HI reactions. There was no significant antigenic variation between WSL, POT and YF viruses using either of those methods. However, definite differences in antigenicity were observed between them and UGS, BAN and ZK viruses. There were no significant differences between UGS, BAN and ZK or between DEN-1 and DEN-2. The serological relationship among flaviviruses is important in establishing diagnosis and epidemiology of these infections in Africa.A relação antigênica de 9 Flavivirus, Febre amarela (YF, Wesselsbron (WSL, Uganda S (UGS, Potiskum (POT, West Nile (WN, Banzi (BAN, Zika (ZK, Dengue tipo 1 (DEN-1 e Dengue tipo2 (DEN-2, foi avaliada por reação de inibição da hemaglutinação cruzada (cross-HI e reação de fixação do complemento cruzada (Cross-CF entre cada um dos virus e seu fluido ascítico homólogo em camundongos. Médias de títulos foram calculadas usando os títulos heterólogos e homólogos. Reações cruzadas CF revelaram maiores variações antigênicas entre virus do que reações cruzadas HI. Não houve variação antigênica significativa entre virus WSL, POT e YF usando cada um dos métodos. Todavia, diferenças definidas da antigenicidade foram observadas entre eles e os vírus UGS, BAN e ZK. Não existiram diferenças significativas entre UGS, BAN e ZK ou entre DEN-1 e DEN-2. A relação sorológica entre Flavivirus é importante para se estabelecer o diagnóstico e a

  15. Antibodies to H5 subtype avian influenza virus and Japanese encephalitis virus in northern pintails (Anas acuta) sampled in Japan

    Science.gov (United States)

    Ramey, Andy M.; Spackman, Erica; Yeh, Jung-Yong; Fujita, Go; Konishi, Kan; Reed, John A.; Wilcox, Benjamin R.; Brown, Justin D.; Stallknecht, David E.

    2013-01-01

    Blood samples from 105 northern pintails (Anas acuta) captured on Hokkaido, Japan were tested for antibodies to avian influenza virus (AIV), Japanese encephalitis virus (JEV), and West Nile virus (WNV) to assess possible involvement of this species in the spread of economically important and potentially zoonotic pathogens. Antibodies to AIV were detected in 64 of 105 samples (61%). Of the 64 positives, 95% and 81% inhibited agglutination of two different H5 AIV antigens (H5N1 and H5N9), respectively. Antibodies to JEV and WNV were detected in five (5%) and none of the samples, respectively. Results provide evidence for prior exposure of migrating northern pintails to H5 AIV which couldhave implications for viral shedding and disease occurrence. Results also provide evidence for limited involvement of this species in the transmission and spread of flaviviruses during spring migration.

  16. Phase 2, multicenter, open-label study of tigatuzumab (CS-1008), a humanized monoclonal antibody targeting death receptor 5, in combination with gemcitabine in chemotherapy-naive patients with unresectable or metastatic pancreatic cancer

    International Nuclear Information System (INIS)

    Forero-Torres, Andres; Infante, Jeffrey R; Waterhouse, David; Wong, Lucas; Vickers, Selwyn; Arrowsmith, Edward; He, Aiwu Ruth; Hart, Lowell; Trent, David; Wade, James; Jin, Xiaoping; Wang, Qiang; Austin, TaShara; Rosen, Michael; Beckman, Robert; Roemeling, Reinhard von; Greenberg, Jonathan; Saleh, Mansoor

    2013-01-01

    Tigatuzumab is the humanized version of the agonistic murine monoclonal antibody TRA-8 that binds to the death receptor 5 and induces apoptosis of human cancer cell lines via the caspase cascade. The combination of tigatuzumab and gemcitabine inhibits tumor growth in murine pancreatic xenografts. This phase 2 trial evaluated the efficacy of tigatuzumab combined with gemcitabine in 62 chemotherapy-naive patients with histologically or cytologically confirmed unresectable or metastatic pancreatic cancer. Patients received intravenous tigatuzumab (8 mg/kg loading dose followed by 3 mg/kg weekly) and gemcitabine (1000 mg/m 2 once weekly for 3 weeks followed by 1 week of rest) until progressive disease (PD) or unacceptable toxicity occurred. The primary end point was progression-free survival (PFS) at 16 weeks. Secondary end points included objective response rate (ORR) (complete responses plus partial responses), duration of response, and overall survival (OS). Safety of the combination was also evaluated. Mean duration of treatment was 18.48 weeks for tigatuzumab and 17.73 weeks for gemcitabine. The PFS rate at 16 weeks was 52.5% (95% confidence interval [CI], 39.3–64.1%). The ORR was 13.1%; 28 (45.9%) patients had stable disease and 14 (23%) patients had PD. Median PFS was 3.9 months (95% CI, 2.2–5.4 months). Median OS was 8.2 months (95% CI, 5.1–9.6 months). The most common adverse events related to tigatuzumab were nausea (35.5%), fatigue (32.3%), and peripheral edema (19.4%). Tigatuzumab combined with gemcitabine was well tolerated and may be clinically active for the treatment of chemotherapy-naive patients with unresectable or metastatic pancreatic cancer

  17. Production of a Human Antibody Library in the Phage-Display Vector pSEX81.

    Science.gov (United States)

    Welschof, M; Little, M; Dörsam, H

    1998-01-01

    Human monoclonal antibodies (MAbs) are more suitable than MAbs of animal origin for clinical applications because of lower hypersensitivity reactions, less formation of circulating immune complexes and lower anti-immunoglobulin responses The classical production of human MAbs via the hybridoma technique or Epstein-Barr virus (EBV) transformation is limited by the instability of cell lines, low antibody production, and the problems of imununizing humans with certain antigens (1,2). A promising alternative 1s the production of human recombinant antibodies (3). Recombinant DNA technology has made it possible to clone human antibody genes in vectors and to generate antibody expression libraries (4-7). One approach has been to amplify and recombine the IgG repertoire of an "immunized" donor. This has been used to isolate several antibodies related to diseases (8,9). In order to obtain more universal antibody libraries the naive IgM repertoire of several "unimmunized" donors were pooled (10,12). The complexity of the combinatorial libraries has been further increased by creating the so-called "semisynthetic" antibody libraries (22-14).

  18. Sequence, structure and function relationships in flaviviruses as assessed by evolutive aspects of its conserved non-structural protein domains.

    Science.gov (United States)

    da Fonseca, Néli José; Lima Afonso, Marcelo Querino; Pedersolli, Natan Gonçalves; de Oliveira, Lucas Carrijo; Andrade, Dhiego Souto; Bleicher, Lucas

    2017-10-28

    Flaviviruses are responsible for serious diseases such as dengue, yellow fever, and zika fever. Their genomes encode a polyprotein which, after cleavage, results in three structural and seven non-structural proteins. Homologous proteins can be studied by conservation and coevolution analysis as detected in multiple sequence alignments, usually reporting positions which are strictly necessary for the structure and/or function of all members in a protein family or which are involved in a specific sub-class feature requiring the coevolution of residue sets. This study provides a complete conservation and coevolution analysis on all flaviviruses non-structural proteins, with results mapped on all well-annotated available sequences. A literature review on the residues found in the analysis enabled us to compile available information on their roles and distribution among different flaviviruses. Also, we provide the mapping of conserved and coevolved residues for all sequences currently in SwissProt as a supplementary material, so that particularities in different viruses can be easily analyzed. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. PERBANDINGAN JARINGAN SYARAF TIRUAN DAN NAIVE BAYES DALAM DETEKSI SESEORANG TERKENA PENYAKIT STROKE

    Directory of Open Access Journals (Sweden)

    I. Rohmana

    2015-07-01

    Full Text Available Tujuan penelitian ini adalah membuat aplikasi Jaringan Syaraf Tiruan dan Naive Bayes untuk memprediksi penyakit stroke dan membandingkan tingkat akuratan dari kedua metode yang digunakan. Sebuah aplikasi software MATLAB diciptakan untuk mendeteksi seseorang Suspect stroke.  Metode yang baik dalam mesin pembelajaran berdasarkan data training adalah Jaringan Syaraf Tiruan dan Naive Bayes, variabel data faktor gejala penyakit stroke digunakan sebagai data training dalam proses pembelajaran dari sistem yang dibuat menentukan prediksi penyakit stroke. Dari 120 data percobaan yang dilakukan, akan dihitung akurasi hasil kerja sistem yang dibagi menjadi data pelatihan dan data pengujian. Diperoleh persentase hasil kerja sistem yaitu Jaringan Syaraf Tiruan sebesar 71,11 persen, sedangkan Naive Bayes sebesar 80,55 persen. Naive Bayes lebih akurat daripada Jaringan Syaraf Tiruan dalam hal pengambilan keputusan data baru namun Jaringan Syaraf Tiruan memiliki teknik yang lebih bagus dibandingkan dengan Naive Bayes. Jaringan Syaraf Tiruan mempunyai karakteristik belajar dari data sebelumnya.The purpose of this research are make application system of Artificial Neural Network and Naive Bayes to predict stroke  and to compare the accuration between of  both methods. An application applying MATLAB software has been invented to detect a stroke suspect. A good method in learning machine based on the training data is Artificial Neural Network and Naive Bayes method, by using the data variable of some common stroke symptoms used as the training data in the learning process of the system which is going to be built to determine whether prediction of stroke disease. From 120 experiments data which had been done, will be counted the accuracy of the system which divided into some training data and the other experiment data. Retrieved the percentage of  accuracy system, The Artificial Neural Network is 71,11 percent whereas Naive Bayes is 80,555 percent. Naive Bayes

  20. Blocking the recruitment of naive CD4+ T cells reverses immunosuppression in breast cancer

    Institute of Scientific and Technical Information of China (English)

    Shicheng Su; Ling Lin; Yunjie Zeng; Nengtai Ouyang; Xiuying Cui; Herui Yao; Fengxi Su; Jian-dong Huang; Judy Lieberman; Qiang Liu; Erwei Song; Jianyou Liao; Jiang Liu; Di Huang; Chonghua He; Fei Chen; LinBing Yang; Wei Wu; Jianing Chen

    2017-01-01

    The origin of tumor-infiltrating Tregs,critical mediators of tumor immunosuppression,is unclear.Here,we show that tumor-infiltrating naive CD4+ T cells and Tregs in human breast cancer have overlapping TCR repertoires,while hardly overlap with circulating Tregs,suggesting that intratumoral Tregs mainly develop from naive T cells in situ rather than from recruited Tregs.Furthermore,the abundance of naive CD4+ T cells and Tregs is closely correlated,both indicating poor prognosis for breast cancer patients.Naive CD4+ T cells adhere to tumor slices in proportion to the abundance of CCLl8-producing macrophages.Moreover,adoptively transferred human naive CD4+ T cells infiltrate human breast cancer orthotopic xenografts in a CCL18-dependent manner.In human breast cancer xenografts in humanized mice,blocking the recruitment of naive CD4+ T cells into tumor by knocking down the expression of PITPNM3,a CCL18 receptor,significantly reduces intratumoral Tregs and inhibits tumor progression.These findings suggest that breast tumor-infiltrating Tregs arise from chemotaxis of circulating naive CD4+ T cells that differentiate into Tregs in situ.Inhibiting naive CD4+ T cell recruitment into tumors by interfering with PITPNM3 recognition of CCL18 may be an attractive strategy for anticancer immunotherapy.

  1. Blocking the recruitment of naive CD4+ T cells reverses immunosuppression in breast cancer

    Science.gov (United States)

    Su, Shicheng; Liao, Jianyou; Liu, Jiang; Huang, Di; He, Chonghua; Chen, Fei; Yang, LinBing; Wu, Wei; Chen, Jianing; Lin, Ling; Zeng, Yunjie; Ouyang, Nengtai; Cui, Xiuying; Yao, Herui; Su, Fengxi; Huang, Jian-dong; Lieberman, Judy; Liu, Qiang; Song, Erwei

    2017-01-01

    The origin of tumor-infiltrating Tregs, critical mediators of tumor immunosuppression, is unclear. Here, we show that tumor-infiltrating naive CD4+ T cells and Tregs in human breast cancer have overlapping TCR repertoires, while hardly overlap with circulating Tregs, suggesting that intratumoral Tregs mainly develop from naive T cells in situ rather than from recruited Tregs. Furthermore, the abundance of naive CD4+ T cells and Tregs is closely correlated, both indicating poor prognosis for breast cancer patients. Naive CD4+ T cells adhere to tumor slices in proportion to the abundance of CCL18-producing macrophages. Moreover, adoptively transferred human naive CD4+ T cells infiltrate human breast cancer orthotopic xenografts in a CCL18-dependent manner. In human breast cancer xenografts in humanized mice, blocking the recruitment of naive CD4+ T cells into tumor by knocking down the expression of PITPNM3, a CCL18 receptor, significantly reduces intratumoral Tregs and inhibits tumor progression. These findings suggest that breast tumor-infiltrating Tregs arise from chemotaxis of circulating naive CD4+ T cells that differentiate into Tregs in situ. Inhibiting naive CD4+ T cell recruitment into tumors by interfering with PITPNM3 recognition of CCL18 may be an attractive strategy for anticancer immunotherapy. PMID:28290464

  2. TEXT CLASSIFICATION USING NAIVE BAYES UPDATEABLE ALGORITHM IN SBMPTN TEST QUESTIONS

    Directory of Open Access Journals (Sweden)

    Ristu Saptono

    2017-01-01

    Full Text Available Document classification is a growing interest in the research of text mining. Classification can be done based on the topics, languages, and so on. This study was conducted to determine how Naive Bayes Updateable performs in classifying the SBMPTN exam questions based on its theme. Increment model of one classification algorithm often used in text classification Naive Bayes classifier has the ability to learn from new data introduces with the system even after the classifier has been produced with the existing data. Naive Bayes Classifier classifies the exam questions based on the theme of the field of study by analyzing keywords that appear on the exam questions. One of feature selection method DF-Thresholding is implemented for improving the classification performance. Evaluation of the classification with Naive Bayes classifier algorithm produces 84,61% accuracy.

  3. Naive Juveniles Are More Likely to Become Breeders after Witnessing Predator Mobbing.

    Science.gov (United States)

    Griesser, Michael; Suzuki, Toshitaka N

    2017-01-01

    Responding appropriately during the first predatory attack in life is often critical for survival. In many social species, naive juveniles acquire this skill from conspecifics, but its fitness consequences remain virtually unknown. Here we experimentally demonstrate how naive juvenile Siberian jays (Perisoreus infaustus) derive a long-term fitness benefit from witnessing knowledgeable adults mobbing their principal predator, the goshawk (Accipiter gentilis). Siberian jays live in family groups of two to six individuals that also can include unrelated nonbreeders. Field observations showed that Siberian jays encounter predators only rarely, and, indeed, naive juveniles do not respond to predator models when on their own but do when observing other individuals mobbing them. Predator exposure experiments demonstrated that naive juveniles had a substantially higher first-winter survival after observing knowledgeable group members mobbing a goshawk model, increasing their likelihood of acquiring a breeding position later in life. Previous research showed that naive individuals may learn from others how to respond to predators, care for offspring, or choose mates, generally assuming that social learning has long-term fitness consequences without empirical evidence. Our results demonstrate a long-term fitness benefit of vertical social learning for naive individuals in the wild, emphasizing its evolutionary importance in animals, including humans.

  4. Two separate defects affecting true naive or virtual memory T cell precursors combine to reduce naive T cell responses with aging.

    Science.gov (United States)

    Renkema, Kristin R; Li, Gang; Wu, Angela; Smithey, Megan J; Nikolich-Žugich, Janko

    2014-01-01

    Naive T cell responses are eroded with aging. We and others have recently shown that unimmunized old mice lose ≥ 70% of Ag-specific CD8 T cell precursors and that many of the remaining precursors acquire a virtual (central) memory (VM; CD44(hi)CD62L(hi)) phenotype. In this study, we demonstrate that unimmunized TCR transgenic (TCRTg) mice also undergo massive VM conversion with age, exhibiting rapid effector function upon both TCR and cytokine triggering. Age-related VM conversion in TCRTg mice directly depended on replacement of the original TCRTg specificity by endogenous TCRα rearrangements, indicating that TCR signals must be critical in VM conversion. Importantly, we found that VM conversion had adverse functional effects in both old wild-type and old TCRTg mice; that is, old VM, but not old true naive, T cells exhibited blunted TCR-mediated, but not IL-15-mediated, proliferation. This selective proliferative senescence correlated with increased apoptosis in old VM cells in response to peptide, but decreased apoptosis in response to homeostatic cytokines IL-7 and IL-15. Our results identify TCR as the key factor in differential maintenance and function of Ag-specific precursors in unimmunized mice with aging, and they demonstrate that two separate age-related defects--drastic reduction in true naive T cell precursors and impaired proliferative capacity of their VM cousins--combine to reduce naive T cell responses with aging.

  5. File list: InP.Bld.50.AllAg.Naive_T_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.Bld.50.AllAg.Naive_T_cells hg19 Input control Blood Naive T cells SRX1425815,SR...X1425816,SRX1425814 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/InP.Bld.50.AllAg.Naive_T_cells.bed ...

  6. Naive Theories of Social Groups

    Science.gov (United States)

    Rhodes, Marjorie

    2012-01-01

    Four studies examined children's (ages 3-10, Total N = 235) naive theories of social groups, in particular, their expectations about how group memberships constrain social interactions. After introduction to novel groups of people, preschoolers (ages 3-5) reliably expected agents from one group to harm members of the other group (rather than…

  7. Left ventricular deformation at 2-year follow-up in treatment-naive rheumatoid arthritis patients is associated with high inflammation parameters

    DEFF Research Database (Denmark)

    Logstrup, B. B.; Masic, D.; Laurbjerg, T. B.

    2015-01-01

    : To assess LV function by speckle-tracking echocardiography and the amount of coronary calcium by coronary computer tomography (CCT) in relation to anti-cyclic citrullinated peptide antibody (anti-CCP) status during a 2-year follow-up period in a open cohort of treatment-naive RA patients. Methods: Thirty...... we measured global longitudinal systolic strain (GLS) and coronary calcium score (Agatston's score) by coronary computer tomography (CCT) at time of diagnosis and at 2-year follow-up. Results: We found GLS similar at baseline and after 2-year follow-up (GLSBASELINE: -16.56+/-3.1% vs. GLS2-YEAR: -16...

  8. Subtrochanteric fractures in bisphosphonate-naive patients

    DEFF Research Database (Denmark)

    Adachi, Jonathan D; Lyles, Kenneth; Boonen, Steven

    2011-01-01

    Our purpose was to characterize the risks of osteoporosis-related subtrochanteric fractures in bisphosphonate-naive individuals. Baseline characteristics of patients enrolled in the HORIZON-Recurrent Fracture Trial with a study-qualifying hip fracture were examined, comparing those who sustained ...

  9. Research and Operational Support for the Study of Militarily Relevant Infectious Diseases of Interest to the United States and Royal Thai Government

    Science.gov (United States)

    2005-01-01

    vaccine ( Varicella vaccine for dose 1 and Hemophilius B vaccine for dose 2). Fifty-one healthy male and female, flavivirus naive infants were enrolled...Bangkok, Thailand. 11th International Conference of Infectious Disease. Cancun, Mexico . 4-8 March 2004. 80. Zhang C, Klungthong C, Monkongdee P, Mammen MP

  10. Evaluation and optimization of SYBR Green real-time reverse transcription polymerase chain reaction as a tool for diagnosis of the Flavivirus genus in Brazil

    Directory of Open Access Journals (Sweden)

    Marilia Farignoli Romeiro

    2016-06-01

    Full Text Available Abstract: INTRODUCTION: The genus Flavivirus includes several pathogenic species that cause severe illness in humans. Therefore, a rapid and accurate molecular method for diagnosis and surveillance of these viruses would be of great importance. Here, we evaluate and optimize a quantitative real-time reverse transcription polymerase chain reaction (RT-PCR method for the diagnosis of the Flavivirus genus. METHODS: We evaluated different commercial kits that use the SYBR Green system for real-time RT-PCR with a primer set that amplifies a fragment of the NS5 flavivirus gene. The specificity and sensitivity of the assay were tested using twelve flaviviruses and ribonucleic acid (RNA transcribed from the yellow fever virus. Additionally, this assay was evaluated using the sera of 410 patients from different regions of Brazil with acute febrile illness and a negative diagnosis for the dengue virus. RESULTS: The real-time RT-PCR amplified all flaviviruses tested at a melting temperature of 79.92 to 83.49°C. A detection limit of 100 copies per ml was determined for this assay. Surprisingly, we detected dengue virus in 4.1% (17/410 of samples from patients with febrile illness and a supposedly negative dengue infection diagnosis. The viral load in patients ranged from 2.1×107to 3.4×103copies per ml. CONCLUSIONS: The real-time RT-PCR method may be very useful for preliminary diagnoses in screenings, outbreaks, and other surveillance studies. Moreover, this assay can be easily applied to monitor viral activity and to measure viral load in pathogenesis studies.

  11. 636 ART-naive patients were enrolled; 361 completed 6 months of ...

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. 636 ART-naive patients were enrolled; 361 completed 6 months of follow-up (282 received supplements and 79 received standard care). 636 ART-naive patients were enrolled; 361 completed 6 months of follow-up (282 received supplements and 79 received standard care).

  12. PENERAPAN NAIVE BAYES PADA INTRUSION DETECTION SYSTEM DENGAN DISKRITISASI VARIABEL

    Directory of Open Access Journals (Sweden)

    I Nyoman Trisna Wirawan

    2015-07-01

    Pada penelitian ini akan dibahas mengenai penerapan naive bayes classifier dengan menggunakan pemilihan atribut berdasarkan pada korelasi serta preprocessing data dengan diskritisasi dengan menggunakan metode mean/standar deviasi untuk atribut kontinu dengan menggunakan 3-interval dan 5-interval. Hasil percobaan menunjukan bahwa penerapan naive bayes pada klasifikasi data yang telah melewati proses diskritisasi mampu memberikan akurasi hingga 89% dengan running time rata-rata adalah 31 detik.

  13. Recombinant Envelope-Proteins with Mutations in the Conserved Fusion Loop Allow Specific Serological Diagnosis of Dengue-Infections.

    Directory of Open Access Journals (Sweden)

    Alexandra Rockstroh

    2015-11-01

    Full Text Available Dengue virus (DENV is a mosquito-borne flavivirus and a major international public health concern in many tropical and sub-tropical areas worldwide. DENV is divided into four major serotypes, and infection with one serotype leads to immunity against the same, but not the other serotypes. The specific diagnosis of DENV-infections via antibody-detection is problematic due to the high degree of cross-reactivity displayed by antibodies against related flaviviruses, such as West Nile virus (WNV, Yellow Fever virus (YFV or Tick-borne encephalitis virus (TBEV. Especially in areas where several flaviviruses co-circulate or in the context of vaccination e.g. against YFV or TBEV, this severely complicates diagnosis and surveillance. Most flavivirus cross-reactive antibodies are produced against the highly conserved fusion loop (FL domain in the viral envelope (E protein. We generated insect-cell derived recombinant E-proteins of the four DENV-serotypes which contain point mutations in the FL domain. By using specific mixtures of these mutant antigens, cross-reactivity against heterologous flaviviruses was strongly reduced, enabling sensitive and specific diagnosis of the DENV-infected serum samples in IgG and IgM-measurements. These results have indications for the development of serological DENV-tests with improved specificity.

  14. CEACAM1 induces B-cell survival and is essential for protective antiviral antibody production

    Science.gov (United States)

    Khairnar, Vishal; Duhan, Vikas; Maney, Sathish Kumar; Honke, Nadine; Shaabani, Namir; Pandyra, Aleksandra A.; Seifert, Marc; Pozdeev, Vitaly; Xu, Haifeng C.; Sharma, Piyush; Baldin, Fabian; Marquardsen, Florian; Merches, Katja; Lang, Elisabeth; Kirschning, Carsten; Westendorf, Astrid M.; Häussinger, Dieter; Lang, Florian; Dittmer, Ulf; Küppers, Ralf; Recher, Mike; Hardt, Cornelia; Scheffrahn, Inka; Beauchemin, Nicole; Göthert, Joachim R.; Singer, Bernhard B.; Lang, Philipp A.; Lang, Karl S.

    2015-01-01

    B cells are essential for antiviral immune defence because they produce neutralizing antibodies, present antigen and maintain the lymphoid architecture. Here we show that intrinsic signalling of CEACAM1 is essential for generating efficient B-cell responses. Although CEACAM1 exerts limited influence on the proliferation of B cells, expression of CEACAM1 induces survival of proliferating B cells via the BTK/Syk/NF-κB-axis. The absence of this signalling cascade in naive Ceacam1−/− mice limits the survival of B cells. During systemic infection with cytopathic vesicular stomatitis virus, Ceacam1−/− mice can barely induce neutralizing antibody responses and die early after infection. We find, therefore, that CEACAM1 is a crucial regulator of B-cell survival, influencing B-cell numbers and protective antiviral antibody responses. PMID:25692415

  15. Genes de susceptibilidad/ resistencia a Flavivirus, implicaciones en la severidad de la infección

    Directory of Open Access Journals (Sweden)

    Jeanette Prada-Arismendy

    2006-07-01

    Full Text Available Las infecciones transmitidas por Flavivirus se encuentran entre las enfermedades transmisibles con mayor incidencia en el mundo. La mayoría de ellas se manifiestan clínicamente como un síndrome febril que puede estar o no acompañado de diversos síntomas. La severidad de estas infecciones es variable con casos asintomáticos y otros que pueden llegar a ser letales, La razón de esta variabilidad en la presentación clínica, se desconoce en humanos. En ratones se han identificado cepas susceptibles y cepas resistentes a la infección por algunos Flavivirus. Por clonación posicional se mapeó el gen responsable de la resistencia a virus West Nile en el cromosoma 5 de ratón y se identificó como oligoadenilato sintetasa 1b (Oas1 b. Este gen codifica una proteína que sintetiza oligómeros de adenina que activan la RNasaL, que a su vez degrada los RNAs virales. Células provenientes de ratones resistentes a la infección por Flavivirus producen menor cantidad de virus que su contraparte susceptible, Recientemente en humanos, se identificó un polimorfismo asociado con susceptibilidad a infección por virus West Nile en el gen de OasL. Sin embargo, el mecanismo bioquímico y molecular exacto por el cual se produce la susceptibilidad no ha sido completamente dilucidado, Este conocimiento permitiría aclarar aspectos de la fisiopatología de estas enfermedades y enfocar la terapéutica desde un punto de vista más específico.

  16. Serologic survey of humans for Flavivirus West Nile in southern Moravia (Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Hubálek, Zdeněk; Kříž, B.; Halouzka, Jiří

    2011-01-01

    Roč. 19, č. 3 (2011), s. 131-133 ISSN 1210-7778 R&D Projects: GA AV ČR IAA600930611 EU Projects: European Commission(XE) 10284 - EDEN Institutional research plan: CEZ:AV0Z60930519 Keywords : West Nile virus * Flavivirus * Moravia * serosurvey Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology http://www.szu.cz/svi/cejph/show_en.php?kat=archiv/2011-3-03

  17. Complement-dependent pathogenicity of brain-specific antibodies in cerebrospinal fluid

    DEFF Research Database (Denmark)

    Asgari, Nasrin; Khorooshi, Reza; Lillevang, Søren T

    2013-01-01

    The specificity and potential pathogenicity of autoantibodies vary between neurological diseases. It is often unclear whether their detection in cerebrospinal fluid (CSF) is a consequence or a cause of pathology. The goal was to test whether administration of brain-specific antibodies into CSF...... would be sufficient for pathology. Purified immunoglobulin G from a neuromyelitis optica patient was injected intrathecally with complement to naive mice. Histopathological analysis at 7 days revealed damage to the ependyma, disruption of the CSF parenchymal barrier and pathologic lesions, distant from...

  18. Arbidol (Umifenovir): A broad-spectrum antiviral drug that inhibits medically important arthropod-borne flaviviruses

    Czech Academy of Sciences Publication Activity Database

    Haviernik, J.; Štefánik, M.; Fojtíková, M.; Kali, S.; Tordo, N.; Rudolf, Ivo; Hubálek, Zdeněk; Eyer, Luděk; Růžek, Daniel

    2018-01-01

    Roč. 10, č. 4 (2018), č. článku 184. ISSN 1999-4915 R&D Projects: GA ČR(CZ) GA16-20054S Institutional support: RVO:68081766 ; RVO:60077344 Keywords : Antiviral activity * Arbidol * Cell-type dependent antiviral effect * Cytotoxicity * Flavivirus * Umifenovir Subject RIV: EE - Microbiology, Virology OBOR OECD: Virology Impact factor: 3.465, year: 2016

  19. Flavivirus and Filovirus EvoPrinters: New alignment tools for the comparative analysis of viral evolution.

    Directory of Open Access Journals (Sweden)

    Thomas Brody

    2017-06-01

    Full Text Available Flavivirus and Filovirus infections are serious epidemic threats to human populations. Multi-genome comparative analysis of these evolving pathogens affords a view of their essential, conserved sequence elements as well as progressive evolutionary changes. While phylogenetic analysis has yielded important insights, the growing number of available genomic sequences makes comparisons between hundreds of viral strains challenging. We report here a new approach for the comparative analysis of these hemorrhagic fever viruses that can superimpose an unlimited number of one-on-one alignments to identify important features within genomes of interest.We have adapted EvoPrinter alignment algorithms for the rapid comparative analysis of Flavivirus or Filovirus sequences including Zika and Ebola strains. The user can input a full genome or partial viral sequence and then view either individual comparisons or generate color-coded readouts that superimpose hundreds of one-on-one alignments to identify unique or shared identity SNPs that reveal ancestral relationships between strains. The user can also opt to select a database genome in order to access a library of pre-aligned genomes of either 1,094 Flaviviruses or 460 Filoviruses for rapid comparative analysis with all database entries or a select subset. Using EvoPrinter search and alignment programs, we show the following: 1 superimposing alignment data from many related strains identifies lineage identity SNPs, which enable the assessment of sublineage complexity within viral outbreaks; 2 whole-genome SNP profile screens uncover novel Dengue2 and Zika recombinant strains and their parental lineages; 3 differential SNP profiling identifies host cell A-to-I hyper-editing within Ebola and Marburg viruses, and 4 hundreds of superimposed one-on-one Ebola genome alignments highlight ultra-conserved regulatory sequences, invariant amino acid codons and evolutionarily variable protein-encoding domains within a

  20. FLAVIdB: A data mining system for knowledge discovery in flaviviruses with direct applications in immunology and vaccinology

    DEFF Research Database (Denmark)

    Olsen, Lars Rønn; Zhang, Guang Lan; Reinherz, Ellis L.

    2011-01-01

    was incorporated into a web-accessible data mining system, combining specialized data analysis tools for integrated analysis of relevant data categories (protein sequences, macromolecular structures, and immune epitopes). The data mining system includes tools for variability and conservation analysis, T......-cell epitope prediction, and characterization of neutralizing components of B-cell epitopes. FLAVIdB is accessible at cvc.dfci.harvard.edu/flavi/  Conclusion: FLAVIdB represents a new generation of databases in which data and tools are integrated into a data mining infrastructures specifically designed to aid...... have been studied extensively, safe and efficient vaccines lack for the majority of the flaviviruses.  Results: We have assembled a database that combines antigenic data of flaviviruses, specialized analysis tools, and workflows for automated complex analyses focusing on applications in immunology...

  1. Characterization of Rabensburg virus, a flavivirus closely related to West Nile virus of the Japanese encephalitis antigenic group

    Czech Academy of Sciences Publication Activity Database

    Aliota, M. T.; Jones, S. A.; Dupuis, A. P.; Ciota, A. T.; Hubálek, Zdeněk; Kramer, L. D.

    2012-01-01

    Roč. 7, č. 6 (2012), e39387 E-ISSN 1932-6203 Institutional support: RVO:68081766 Keywords : Insect-specific flaviviruses * Northeastern United-States * Culex pipiens Subject RIV: EE - Microbiology, Virology Impact factor: 3.730, year: 2012

  2. Complete sequence of two tick-borne flaviviruses isolated from Siberia and the UK: analysis and significance of the 5' and 3'-UTRs.

    Science.gov (United States)

    Gritsun, T S; Venugopal, K; Zanotto, P M; Mikhailov, M V; Sall, A A; Holmes, E C; Polkinghorne, I; Frolova, T V; Pogodina, V V; Lashkevich, V A; Gould, E A

    1997-05-01

    The complete nucleotide sequence of two tick-transmitted flaviviruses, Vasilchenko (Vs) from Siberia and louping ill (LI) from the UK, have been determined. The genomes were respectively, 10928 and 10871 nucleotides (nt) in length. The coding strategy and functional protein sequence motifs of tick-borne flaviviruses are presented in both Vs and LI viruses. The phylogenies based on maximum likelihood, maximum parsimony and distance analysis of the polyproteins, identified Vs virus as a member of the tick-borne encephalitis virus subgroup within the tick-borne serocomplex, genus Flavivirus, family Flaviviridae. Comparative alignment of the 3'-untranslated regions revealed deletions of different lengths essentially at the same position downstream of the stop codon for all tick-borne viruses. Two direct 27 nucleotide repeats at the 3'-end were found only for Vs and LI virus. Immediately following the deletions a region of 332-334 nt with relatively conserved primary structure (67-94% identity) was observed at the 3'-non-coding end of the virus genome. Pairwise comparisons of the nucleotide sequence data revealed similar levels of variation between the coding region, and the 5' and 3'-termini of the genome, implying an equivalent strong selective control for translated and untranslated regions. Indeed the predicted folding of the 5' and 3'-untranslated regions revealed patterns of stem and loop structures conserved for all tick-borne flaviviruses suggesting a purifying selection for preservation of essential RNA secondary structures which could be involved in translational control and replication. The possible implications of these findings are discussed.

  3. Preliminary characterization of (nucleoside-2′-O-)-methyltransferase crystals from Meaban and Yokose flaviviruses

    International Nuclear Information System (INIS)

    Mastrangelo, Eloise; Bollati, Michela; Milani, Mario; Lamballeire, Xavier de; Brisbare, Nadege; Dalle, Karen; Lantez, Violaine; Egloff, Marie-Pierre; Coutard, Bruno; Canard, Bruno; Gould, Ernest; Forrester, Naomi; Bolognesi, Martino

    2006-01-01

    Two methyltransferases from flaviviruses (Meaban and Yokose viruses) have been overexpressed and crystallized. Diffraction data and characterization of the two crystal forms are presented, together with a preliminary molecular-replacement solution for both enzymes. Viral methyltranferases (MTase) are involved in the third step of the mRNA-capping process, transferring a methyl group from S-adenosyl-l-methionine (SAM) to the capped mRNA. MTases are classified into two groups: (guanine-N7)-methyltransferases (N7MTases), which add a methyl group onto the N7 atom of guanine, and (nucleoside-2′-O-)-methyltransferases (2′OMTases), which add a methyl group to a ribose hydroxyl. The MTases of two flaviviruses, Meaban and Yokose viruses, have been overexpressed, purified and crystallized in complex with SAM. Characterization of the crystals together with details of preliminary X-ray diffraction data collection (at 2.8 and 2.7 Å resolution, respectively) are reported here. The sequence homology relative to Dengue virus 2′OMTase and the structural conservation of specific residues in the putative active sites suggest that both enzymes belong to the 2′OMTase subgroup

  4. Preliminary characterization of (nucleoside-2′-O-)-methyltransferase crystals from Meaban and Yokose flaviviruses

    Energy Technology Data Exchange (ETDEWEB)

    Mastrangelo, Eloise; Bollati, Michela; Milani, Mario [Department of Biomolecular Sciences and Biotechnology, CNR-INFM, University of Milano, Via Celoria 26, 20133 Milano (Italy); Lamballeire, Xavier de; Brisbare, Nadege [Unité des Virus Emergents, Faculté de Médecine, 27 Boulevard Jean Moulin, 13005 Marseille (France); Dalle, Karen; Lantez, Violaine; Egloff, Marie-Pierre; Coutard, Bruno; Canard, Bruno [Laboratoire Architecture et Fonction des Macromolécules Biologiques, UMR 6098 CNRS ESIL, Case 932, 163 Avenue de Luminy, 13288 Marseille CEDEX 9 (France); Gould, Ernest; Forrester, Naomi [CEH Oxford, Mansfield Road, Oxford OX1 3SR (United Kingdom); Bolognesi, Martino, E-mail: martino.bolognesi@unimi.it [Department of Biomolecular Sciences and Biotechnology, CNR-INFM, University of Milano, Via Celoria 26, 20133 Milano (Italy)

    2006-08-01

    Two methyltransferases from flaviviruses (Meaban and Yokose viruses) have been overexpressed and crystallized. Diffraction data and characterization of the two crystal forms are presented, together with a preliminary molecular-replacement solution for both enzymes. Viral methyltranferases (MTase) are involved in the third step of the mRNA-capping process, transferring a methyl group from S-adenosyl-l-methionine (SAM) to the capped mRNA. MTases are classified into two groups: (guanine-N7)-methyltransferases (N7MTases), which add a methyl group onto the N7 atom of guanine, and (nucleoside-2′-O-)-methyltransferases (2′OMTases), which add a methyl group to a ribose hydroxyl. The MTases of two flaviviruses, Meaban and Yokose viruses, have been overexpressed, purified and crystallized in complex with SAM. Characterization of the crystals together with details of preliminary X-ray diffraction data collection (at 2.8 and 2.7 Å resolution, respectively) are reported here. The sequence homology relative to Dengue virus 2′OMTase and the structural conservation of specific residues in the putative active sites suggest that both enzymes belong to the 2′OMTase subgroup.

  5. A Naive-Bayes classifier for damage detection in engineering materials

    Energy Technology Data Exchange (ETDEWEB)

    Addin, O. [Laboratory of Intelligent Systems, Institute of Advanced Technology, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia); Sapuan, S.M. [Department of Mechanical and Manufacturing Engineering, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia)]. E-mail: sapuan@eng.upm.edu.my; Mahdi, E. [Department of Aerospace Engineering, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia); Othman, M. [Department of Communication Technology and Networks, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia)

    2007-07-01

    This paper is intended to introduce the Bayesian network in general and the Naive-Bayes classifier in particular as one of the most successful classification systems to simulate damage detection in engineering materials. A method for feature subset selection has also been introduced too. The method is based on mean and maximum values of the amplitudes of waves after dividing them into folds then grouping them by a clustering algorithm (e.g. k-means algorithm). The Naive-Bayes classifier and the feature sub-set selection method were analyzed and tested on two sets of data. The data sets were conducted based on artificial damages created in quasi isotopic laminated composites of the AS4/3501-6 graphite/epoxy system and ball bearing of the type 6204 with a steel cage. The Naive-Bayes classifier and the proposed feature subset selection algorithm have been shown as efficient techniques for damage detection in engineering materials.

  6. Development of naive personality perception

    OpenAIRE

    Hayashi, Tomoyuki

    2004-01-01

    Lay persons usually understand that the personality has consistency and causality. They also have the knowledge of what contents the personality consists of. Research of "theories of mind," which focuses on the developmental processes of the naive understanding of mind, suggests three stages : (a) alignment of actions (imitation) fosters the foundation of social cognition in young children (i.e., understanding that the mind causes behaviors, grasping the identity of a person, and discovering ...

  7. Simplifying complex sequence information: a PCP-consensus protein binds antibodies against all four Dengue serotypes.

    Science.gov (United States)

    Bowen, David M; Lewis, Jessica A; Lu, Wenzhe; Schein, Catherine H

    2012-09-14

    Designing proteins that reflect the natural variability of a pathogen is essential for developing novel vaccines and drugs. Flaviviruses, including Dengue (DENV) and West Nile (WNV), evolve rapidly and can "escape" neutralizing monoclonal antibodies by mutation. Designing antigens that represent many distinct strains is important for DENV, where infection with a strain from one of the four serotypes may lead to severe hemorrhagic disease on subsequent infection with a strain from another serotype. Here, a DENV physicochemical property (PCP)-consensus sequence was derived from 671 unique sequences from the Flavitrack database. PCP-consensus proteins for domain 3 of the envelope protein (EdomIII) were expressed from synthetic genes in Escherichia coli. The ability of the purified consensus proteins to bind polyclonal antibodies generated in response to infection with strains from each of the four DENV serotypes was determined. The initial consensus protein bound antibodies from DENV-1-3 in ELISA and Western blot assays. This sequence was altered in 3 steps to incorporate regions of maximum variability, identified as significant changes in the PCPs, characteristic of DENV-4 strains. The final protein was recognized by antibodies against all four serotypes. Two amino acids essential for efficient binding to all DENV antibodies are part of a discontinuous epitope previously defined for a neutralizing monoclonal antibody. The PCP-consensus method can significantly reduce the number of experiments required to define a multivalent antigen, which is particularly important when dealing with pathogens that must be tested at higher biosafety levels. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Children and Adolescents' Understandings of Family Resemblance: A Study of Naive Inheritance Concepts

    Science.gov (United States)

    Williams, Joanne M.

    2012-01-01

    This paper aims to provide developmental data on two connected naive inheritance concepts and to explore the coherence of children's naive biology knowledge. Two tasks examined children and adolescents' (4, 7, 10, and 14 years) conceptions of phenotypic resemblance across kin (in physical characteristics, disabilities, and personality traits). The…

  9. The yellow fever 17D vaccine virus as a vector for the expression of foreign proteins: development of new live flavivirus vaccines

    Directory of Open Access Journals (Sweden)

    Myrna C Bonaldo

    2000-01-01

    Full Text Available The Flaviviridae is a family of about 70 mostly arthropod-borne viruses many of which are major public health problems with members being present in most continents. Among the most important are yellow fever (YF, dengue with its four serotypes and Japanese encephalitis virus. A live attenuated virus is used as a cost effective, safe and efficacious vaccine against YF but no other live flavivirus vaccines have been licensed. The rise of recombinant DNA technology and its application to study flavivirus genome structure and expression has opened new possibilities for flavivirus vaccine development. One new approach is the use of cDNAs encopassing the whole viral genome to generate infectious RNA after in vitro transcription. This methodology allows the genetic mapping of specific viral functions and the design of viral mutants with considerable potential as new live attenuated viruses. The use of infectious cDNA as a carrier for heterologous antigens is gaining importance as chimeric viruses are shown to be viable, immunogenic and less virulent as compared to the parental viruses. The use of DNA to overcome mutation rates intrinsic of RNA virus populations in conjunction with vaccine production in cell culture should improve the reliability and lower the cost for production of live attenuated vaccines. The YF virus despite a long period ignored by researchers probably due to the effectiveness of the vaccine has made a come back, both in nature as human populations grow and reach endemic areas as well as in the laboratory being a suitable model to understand the biology of flaviviruses in general and providing new alternatives for vaccine development through the use of the 17D vaccine strain.

  10. First isolation of Aedes flavivirus in the Western Hemisphere and evidence of vertical transmission in the mosquito Aedes (Stegomyia) albopictus (Diptera: Culicidae)

    Energy Technology Data Exchange (ETDEWEB)

    Haddow, Andrew D., E-mail: adhaddow@gmail.com [Institute for Human Infections and Immunity, Center for Emerging Infectious Diseases and Biodefense, Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609 (United States); Guzman, Hilda; Popov, Vsevolod L. [Institute for Human Infections and Immunity, Center for Emerging Infectious Diseases and Biodefense, Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609 (United States); Wood, Thomas G.; Widen, Steven G. [Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555-0609 (United States); Haddow, Alastair D. [Mercy Clinic, 2115 S. Fremont, Springfield, MO 65804 (United States); Tesh, Robert B.; Weaver, Scott C. [Institute for Human Infections and Immunity, Center for Emerging Infectious Diseases and Biodefense, Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609 (United States)

    2013-06-05

    We report here the first evidence of vertical transmission of Aedes flavivirus (AEFV) and its first isolation in the Western Hemisphere. AEFV strain SPFLD-MO-2011-MP6 was isolated in C6/36 cells from a pool of male Aedes albopictus mosquitoes that were reared to adults from larvae collected in southwest Missouri, USA, in 2011. Electron micrographs of the virus showed virions of approximately 45 nm in diameter with morphological characteristics associated with flaviviruses. The genomic sequence demonstrated that AEFV-SPFLD-MO-2011-MP6 shares a high degree of nucleotide and amino acid sequence identity with the AEFV Narita-21 strain, isolated in Japan in 2003. Intracerebral inoculation of newborn mice with the virus failed to produce observable illness or death and the virus did not replicate in vertebrate cells, consistent with a lack of vertebrate host range. - Highlights: ► The first report of Aedes flavivirus (AEFV) in the Western Hemisphere. ► The first evidence of vertical transmission of AEFV in mosquitoes. ► The first electron micrograph of AEFV. ► The first attempt to infect animals with AEFV.

  11. First isolation of Aedes flavivirus in the Western Hemisphere and evidence of vertical transmission in the mosquito Aedes (Stegomyia) albopictus (Diptera: Culicidae)

    International Nuclear Information System (INIS)

    Haddow, Andrew D.; Guzman, Hilda; Popov, Vsevolod L.; Wood, Thomas G.; Widen, Steven G.; Haddow, Alastair D.; Tesh, Robert B.; Weaver, Scott C.

    2013-01-01

    We report here the first evidence of vertical transmission of Aedes flavivirus (AEFV) and its first isolation in the Western Hemisphere. AEFV strain SPFLD-MO-2011-MP6 was isolated in C6/36 cells from a pool of male Aedes albopictus mosquitoes that were reared to adults from larvae collected in southwest Missouri, USA, in 2011. Electron micrographs of the virus showed virions of approximately 45 nm in diameter with morphological characteristics associated with flaviviruses. The genomic sequence demonstrated that AEFV-SPFLD-MO-2011-MP6 shares a high degree of nucleotide and amino acid sequence identity with the AEFV Narita-21 strain, isolated in Japan in 2003. Intracerebral inoculation of newborn mice with the virus failed to produce observable illness or death and the virus did not replicate in vertebrate cells, consistent with a lack of vertebrate host range. - Highlights: ► The first report of Aedes flavivirus (AEFV) in the Western Hemisphere. ► The first evidence of vertical transmission of AEFV in mosquitoes. ► The first electron micrograph of AEFV. ► The first attempt to infect animals with AEFV

  12. PCA criterion for SVM (MLP) classifier for flavivirus biomarker from salivary SERS spectra at febrile stage.

    Science.gov (United States)

    Radzol, A R M; Lee, Khuan Y; Mansor, W; Omar, I S

    2016-08-01

    Non-structural protein (NS1) has been conceded as one of the biomarkers for flavivirus that causes diseases with life threatening consequences. NS1 is an antigen that allows detection of the illness at febrile stage, mostly from blood samples currently. Our work here intends to define an optimum model for PCA-SVM with MLP kernel for classification of flavivirus biomarker, NS1 molecule, from SERS spectra of saliva, which to the best of our knowledge has never been explored. Since performance of the model depends on the PCA criterion and MLP parameters, both are examined in tandem. Input vector to classifier determined by each PCA criterion is subjected to brute force tuning of MLP parameters for entirety. Its performance is also compared to our previous works where a Linear and RBF kernel are used. It is found that the best PCA-SVM (MLP) model can be defined by 5 PCs from Cattel's Scree test for PCA, together with P1 and P2 values of 0.1 and -0.2 respectively, with a classification performance of [96.9%, 93.8%, 100.0%].

  13. Hepatic insulin resistance in antipsychotic naive schizophrenic patients: stable isotope studies of glucose metabolism

    NARCIS (Netherlands)

    van Nimwegen, Lonneke J. M.; Storosum, Jitschak G.; Blumer, Regje M. E.; Allick, Gideon; Venema, Henk W.; de Haan, Lieuwe; Becker, Hiske; van Amelsvoort, Therese; Ackermans, Mariette T.; Fliers, Eric; Serlie, Mireille J. M.; Sauerwein, Hans P.

    2008-01-01

    OBJECTIVE: Our objective was to measure insulin sensitivity and body composition in antipsychotic-naive patients with DSM IV schizophrenia and/or schizoaffective disorder compared with matched controls. DESIGN: Seven antipsychotic medication-naive patients fulfilling the DSM IV A criteria for

  14. Risk of erectile dysfunction in transfusion-naive thalassemia men: a nationwide population-based retrospective cohort study.

    Science.gov (United States)

    Chen, Yu-Guang; Lin, Te-Yu; Lin, Cheng-Li; Dai, Ming-Shen; Ho, Ching-Liang; Kao, Chia-Hung

    2015-04-01

    Based on the mechanism of pathophysiology, thalassemia major or transfusion-dependent thalassemia patients may have an increased risk of developing organic erectile dysfunction resulting from hypogonadism. However, there have been few studies investigating the association between erectile dysfunction and transfusion-naive thalassemia populations. We constructed a population-based cohort study to elucidate the association between transfusion-naive thalassemia populations and organic erectile dysfunction. This nationwide population-based cohort study involved analyzing data from 1998 to 2010 obtained from the Taiwanese National Health Insurance Research Database, with a follow-up period extending to the end of 2011. We identified men with transfusion-naive thalassemia and selected a comparison cohort that was frequency-matched with these according to age, and year of diagnosis thalassemia at a ratio of 1 thalassemia man to 4 control men. We analyzed the risks for transfusion-naive thalassemia men and organic erectile dysfunction by using Cox proportional hazards regression models. In this study, 588 transfusion-naive thalassemia men and 2337 controls were included. Total 12 patients were identified within the thalassaemia group and 10 within the control group. The overall risks for developing organic erectile dysfunction were 4.56-fold in patients with transfusion-naive thalassemia men compared with the comparison cohort after we adjusted for age and comorbidities. Our long-term cohort study results showed that in transfusion-naive thalassemia men, there was a higher risk for the development of organic erectile dysfunction, particularly in those patients with comorbidities.

  15. Evaluation of the impact of chitosan/DNA nanoparticles on the differentiation of human naive CD4+ T cells

    Science.gov (United States)

    Liu, Lanxia; Bai, Yuanyuan; Zhu, Dunwan; Song, Liping; Wang, Hai; Dong, Xia; Zhang, Hailing; Leng, Xigang

    2011-06-01

    Chitosan (CS) is one of the most widely studied polymers in non-viral gene delivery since it is a cationic polysaccharide that forms nanoparticles with DNA and hence protects the DNA against digestion by DNase. However, the impact of CS/DNA nanoparticle on the immune system still remains poorly understood. Previous investigations did not found CS/DNA nanoparticles had any significant impact on the function of human and murine macrophages. To date, little is known about the interaction between CS/DNA nanoparticles and naive CD4+ T cells. This study was designed to investigate whether CS/DNA nanoparticles affect the initial differentiation direction of human naive CD4+ T cells. The indirect impact of CS/DNA nanoparticles on naive CD4+ T cell differentiation was investigated by incubating the nanoparticles with human macrophage THP-1 cells in one chamber of a transwell co-incubation system, with the enriched human naive CD4+ T cells being placed in the other chamber of the transwell. The nanoparticles were also co-incubated with the naive CD4+ T cells to explore their direct impact on naive CD4+ T cell differentiation by measuring the release of IL-4 and IFN-γ from the cells. It was demonstrated that CS/DNA nanoparticles induced slightly elevated production of IL-12 by THP-1 cells, possibly owing to the presence of CpG motifs in the plasmid. However, this macrophage stimulating activity was much less significant as compared with lipopolysaccharide and did not impact on the differentiation of the naive CD4+ T cells. It was also demonstrated that, when directly exposed to the naive CD4+ T cells, the nanoparticles induced neither the activation of the naive CD4+ T cells in the absence of recombinant cytokines (recombinant human IL-4 or IFN-γ) that induce naive CD4+ T cell polarization, nor any changes in the differentiation direction of naive CD4+ T cells in the presence of the corresponding cytokines.

  16. Evaluation of the impact of chitosan/DNA nanoparticles on the differentiation of human naive CD4+ T cells

    International Nuclear Information System (INIS)

    Liu Lanxia; Bai Yuanyuan; Zhu Dunwan; Song Liping; Wang Hai; Dong Xia; Zhang Hailing; Leng Xigang

    2011-01-01

    Chitosan (CS) is one of the most widely studied polymers in non-viral gene delivery since it is a cationic polysaccharide that forms nanoparticles with DNA and hence protects the DNA against digestion by DNase. However, the impact of CS/DNA nanoparticle on the immune system still remains poorly understood. Previous investigations did not found CS/DNA nanoparticles had any significant impact on the function of human and murine macrophages. To date, little is known about the interaction between CS/DNA nanoparticles and naive CD4 + T cells. This study was designed to investigate whether CS/DNA nanoparticles affect the initial differentiation direction of human naive CD4 + T cells. The indirect impact of CS/DNA nanoparticles on naive CD4 + T cell differentiation was investigated by incubating the nanoparticles with human macrophage THP-1 cells in one chamber of a transwell co-incubation system, with the enriched human naive CD4 + T cells being placed in the other chamber of the transwell. The nanoparticles were also co-incubated with the naive CD4 + T cells to explore their direct impact on naive CD4 + T cell differentiation by measuring the release of IL-4 and IFN-γ from the cells. It was demonstrated that CS/DNA nanoparticles induced slightly elevated production of IL-12 by THP-1 cells, possibly owing to the presence of CpG motifs in the plasmid. However, this macrophage stimulating activity was much less significant as compared with lipopolysaccharide and did not impact on the differentiation of the naive CD4 + T cells. It was also demonstrated that, when directly exposed to the naive CD4 + T cells, the nanoparticles induced neither the activation of the naive CD4 + T cells in the absence of recombinant cytokines (recombinant human IL-4 or IFN-γ) that induce naive CD4 + T cell polarization, nor any changes in the differentiation direction of naive CD4 + T cells in the presence of the corresponding cytokines.

  17. Detection and quantification of microcystins (cyanobacterial hepatotoxins) with recombinant antibody fragments isolated from a naïve human phage display library.

    Science.gov (United States)

    McElhiney, J; Lawton, L A; Porter, A J

    2000-12-01

    Single-chain antibody fragments against the cyanobacterial hepatotoxin microcystin-LR were isolated from a naive human phage display library and expressed in Escherichia coli. In competition enzyme-linked immunosorbent assay (ELISA), the most sensitive antibody clone selected from the library detected free microcystin-LR with an IC(50) value of 4 microM. It was found to cross react with three other microcystin variants - microcystin-RR, microcystin-LW and microcystin-LF - and detected microcystins in extracts of the cyanobacterium Microcystis aeruginosa, found to contain the toxins by high-performance liquid chromatography (HPLC). The quantification of microcystins in these extracts by ELISA and HPLC showed good correlation. Although the antibody isolated in this study was considerably less sensitive than the polyclonal and monoclonal antibodies already available for microcystin detection, phage display technology represents a cheaper, more rapid alternative for the production of anti-microcystin antibodies than the methods currently in use.

  18. Insulin degludec versus insulin glargine in insulin-naive patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Zinman, Bernard; Philis-Tsimikas, Athena; Cariou, Bertrand

    2012-01-01

    To compare ultra-long-acting insulin degludec with glargine for efficacy and safety in insulin-naive patients with type 2 diabetes inadequately controlled with oral antidiabetic drugs (OADs).......To compare ultra-long-acting insulin degludec with glargine for efficacy and safety in insulin-naive patients with type 2 diabetes inadequately controlled with oral antidiabetic drugs (OADs)....

  19. Trastuzumab mediates antibody-dependent cell-mediated cytotoxicity and phagocytosis to the same extent in both adjuvant and metastatic HER2/neu breast cancer patients.

    Science.gov (United States)

    Petricevic, Branka; Laengle, Johannes; Singer, Josef; Sachet, Monika; Fazekas, Judit; Steger, Guenther; Bartsch, Rupert; Jensen-Jarolim, Erika; Bergmann, Michael

    2013-12-12

    Monoclonal antibodies (mAb), such as trastuzumab are a valuable addition to breast cancer therapy. Data obtained from neoadjuvant settings revealed that antibody-dependent cell-mediated cytotoxicity (ADCC) is a major mechanism of action for the mAb trastuzumab. Conflicting results still call into question whether disease progression, prolonged treatment or concomitant chemotherapy influences ADCC and related immunological phenomena. We analyzed the activity of ADCC and antibody-dependent cell-mediated phagocytosis (ADCP) of peripheral blood mononuclear cells (PBMCs) from human epidermal growth factor receptor 2 (HER2/neu) positive breast cancer patients receiving trastuzumab therapy either in an adjuvant (n = 13) or metastatic (n = 15) setting as well as from trastuzumab treatment-naive (t-naive) HER2/neu negative patients (n = 15). PBMCs from healthy volunteers (n = 24) were used as controls. ADCC and ADCP activity was correlated with the expression of antibody binding Fc-gamma receptor (FcγR)I (CD64), FcγRII (CD32) and FcγRIII (CD16) on CD14+ (monocytes) and CD56+ (NK) cells, as well as the expression of CD107a+ (LAMP-1) on CD56+ cells and the total amount of CD4+CD25+FOXP3+ (Treg) cells. In metastatic patients, markers were correlated with progression-free survival (PFS). ADCC activity was significantly down regulated in metastatic, adjuvant and t-naive patient cohorts as compared to healthy controls. Reduced ADCC activity was inversely correlated with the expression of CD107a on CD56+ cells in adjuvant patients. ADCC and ADCP activity of the patient cohorts were similar, regardless of treatment duration or additional chemotherapy. PFS in metastatic patients inversely correlated with the number of peripheral Treg cells. The reduction of ADCC in patients as compared to healthy controls calls for adjuvant strategies, such as immune-enhancing agents, to improve the activity of trastuzumab. However, efficacy of trastuzumab-specific ADCC and ADCP appears not to

  20. Naive Fault Tree : formulation of the approach

    NARCIS (Netherlands)

    Rajabalinejad, M

    2017-01-01

    Naive Fault Tree (NFT) accepts a single value or a range of values for each basic event and returns values for the top event. This accommodates the need of commonly used Fault Trees (FT) for precise data making them prone to data concerns and limiting their area of application. This paper extends

  1. Anti-Glycoprotein G Antibodies of Herpes Simplex Virus 2 Contribute to Complete Protection after Vaccination in Mice and Induce Antibody-Dependent Cellular Cytotoxicity and Complement-Mediated Cytolysis

    Directory of Open Access Journals (Sweden)

    Staffan Görander

    2014-11-01

    Full Text Available We investigated the role of antibodies against the mature portion of glycoprotein G (mgG-2 of herpes simplex virus 2 (HSV-2 in protective immunity after vaccination. Mice were immunized intramuscularly with mgG-2 and oligodeoxynucleotides containing two CpG motifs plus alum as adjuvant. All C57BL/6 mice survived and presented no genital or systemic disease. High levels of immunoglobulin G subclass 1 (IgG1 and IgG2 antibodies were detected and re-stimulated splenic CD4+ T cells proliferated and produced IFN-γ. None of the sera from immunized mice exhibited neutralization, while all sera exerted antibody-dependent cellular cytotoxicity (ADCC and complement-mediated cytolysis (ACMC activity. Passive transfer of anti-mgG-2 monoclonal antibodies, or immune serum, to naive C57BL/6 mice did not limit disease progression. Immunized B‑cell KO mice presented lower survival rate and higher vaginal viral titers, as compared with vaccinated B-cell KO mice after passive transfer of immune serum and vaccinated C57BL/6 mice. Sera from mice that were vaccinated subcutaneously and intranasally with mgG-2 presented significantly lower titers of IgG antibodies and lower ADCC and ACMC activity. We conclude that anti-mgG-2 antibodies were of importance to limit genital HSV‑2 infection. ADCC and ACMC activity are potentially important mechanisms in protective immunity, and could tentatively be evaluated in future animal vaccine studies and in clinical trials.

  2. Modulation of Dengue/Zika Virus Pathogenicity by Antibody-Dependent Enhancement and Strategies to Protect Against Enhancement in Zika Virus Infection

    Directory of Open Access Journals (Sweden)

    Rekha Khandia

    2018-04-01

    Full Text Available Antibody-dependent enhancement (ADE is a phenomenon in which preexisting poorly neutralizing antibodies leads to enhanced infection. It is a serious concern with mosquito-borne flaviviruses such as Dengue virus (DENV and Zika virus (ZIKV. In vitro experimental evidences have indicated the preventive, as well as a pathogenicity-enhancing role, of preexisting DENV antibodies in ZIKV infections. ADE has been confirmed in DENV but not ZIKV infections. Principally, the Fc region of the anti-DENV antibody binds with the fragment crystallizable gamma receptor (FcγR, and subsequent C1q interactions and immune effector functions are responsible for the ADE. In contrast to normal DENV infections, with ADE in DENV infections, inhibition of STAT1 phosphorylation and a reduction in IRF-1 gene expression, NOS2 levels, and RIG-1 and MDA-5 expression levels occurs. FcγRIIA is the most permissive FcγR for DENV-ADE, and under hypoxic conditions, hypoxia-inducible factor-1 alpha transcriptionally enhances expression levels of FcγRIIA, which further enhances ADE. To produce therapeutic antibodies with broad reactivity to different DENV serotypes, as well as to ZIKV, bispecific antibodies, Fc region mutants, modified Fc regions, and anti-idiotypic antibodies may be engineered. An in-depth understanding of the immunological and molecular mechanisms of DENV-ADE of ZIKV pathogenicity will be useful for the design of common and safe therapeutics and prophylactics against both viral pathogens. The present review discusses the role of DENV antibodies in modulating DENV/ZIKV pathogenicity/infection and strategies to counter ADE to protect against Zika infection.

  3. Improving Naive Bayes with Online Feature Selection for Quick Adaptation to Evolving Feature Usefulness

    Energy Technology Data Exchange (ETDEWEB)

    Pon, R K; Cardenas, A F; Buttler, D J

    2007-09-19

    The definition of what makes an article interesting varies from user to user and continually evolves even for a single user. As a result, for news recommendation systems, useless document features can not be determined a priori and all features are usually considered for interestingness classification. Consequently, the presence of currently useless features degrades classification performance [1], particularly over the initial set of news articles being classified. The initial set of document is critical for a user when considering which particular news recommendation system to adopt. To address these problems, we introduce an improved version of the naive Bayes classifier with online feature selection. We use correlation to determine the utility of each feature and take advantage of the conditional independence assumption used by naive Bayes for online feature selection and classification. The augmented naive Bayes classifier performs 28% better than the traditional naive Bayes classifier in recommending news articles from the Yahoo! RSS feeds.

  4. Antiviral activity of the adenosine analogue BCX4430 against West Nile virus and tick-borne flaviviruses

    Czech Academy of Sciences Publication Activity Database

    Eyer, Luděk; Zouharová, D.; Širmarová, J.; Fojtiková, M.; Štefánik, M.; Haviernik, J.; Nencka, Radim; De Clercq, E.; Růžek, Daniel

    2017-01-01

    Roč. 142, JUN (2017), s. 63-67 ISSN 0166-3542 R&D Projects: GA MZd(CZ) NV16-34238A; GA ČR(CZ) GA16-20054S Institutional support: RVO:60077344 ; RVO:61388963 Keywords : BCX4430 * Flavivirus * adenosine analogue * nucleoside inhibitor * antiviral activity * cytotoxicity Subject RIV: EE - Microbiology, Virology OBOR OECD: Virology Impact factor: 4.271, year: 2016

  5. A rapid and quantitative assay for measuring antibody-mediated neutralization of West Nile virus infection

    International Nuclear Information System (INIS)

    Pierson, Theodore C.; Sanchez, Melissa D.; Puffer, Bridget A.; Ahmed, Asim A.; Geiss, Brian J.; Valentine, Laura E.; Altamura, Louis A.; Diamond, Michael S.; Doms, Robert W.

    2006-01-01

    West Nile virus (WNV) is a neurotropic flavivirus within the Japanese encephalitis antigenic complex that is responsible for causing West Nile encephalitis in humans. The surface of WNV virions is covered by a highly ordered icosahedral array of envelope proteins that is responsible for mediating attachment and fusion with target cells. These envelope proteins are also primary targets for the generation of neutralizing antibodies in vivo. In this study, we describe a novel approach for measuring antibody-mediated neutralization of WNV infection using virus-like particles that measure infection as a function of reporter gene expression. These reporter virus particles (RVPs) are produced by complementation of a sub-genomic replicon with WNV structural proteins provided in trans using conventional DNA expression vectors. The precision and accuracy of this approach stem from an ability to measure the outcome of the interaction between antibody and viral antigens under conditions that satisfy the assumptions of the law of mass action as applied to virus neutralization. In addition to its quantitative strengths, this approach allows the production of WNV RVPs bearing the prM-E proteins of different WNV strains and mutants, offering considerable flexibility for the study of the humoral immune response to WNV in vitro. WNV RVPs are capable of only a single round of infection, can be used under BSL-2 conditions, and offer a rapid and quantitative approach for detecting virus entry and its inhibition by neutralizing antibody

  6. The Hayflick Limit May Determine the Effective Clonal Diversity of Naive T Cells.

    Science.gov (United States)

    Ndifon, Wilfred; Dushoff, Jonathan

    2016-06-15

    Having a large number of sufficiently abundant T cell clones is important for adequate protection against diseases. However, as shown in this paper and elsewhere, between young adulthood and >70 y of age the effective clonal diversity of naive CD4/CD8 T cells found in human blood declines by a factor of >10. (Effective clonal diversity accounts for both the number and the abundance of T cell clones.) The causes of this observation are incompletely understood. A previous study proposed that it might result from the emergence of certain rare, replication-enhancing mutations in T cells. In this paper, we propose an even simpler explanation: that it results from the loss of T cells that have attained replicative senescence (i.e., the Hayflick limit). Stochastic numerical simulations of naive T cell population dynamics, based on experimental parameters, show that the rate of homeostatic T cell proliferation increases after the age of ∼60 y because naive T cells collectively approach replicative senescence. This leads to a sharp decline of effective clonal diversity after ∼70 y, in agreement with empirical data. A mathematical analysis predicts that, without an increase in the naive T cell proliferation rate, this decline will occur >50 yr later than empirically observed. These results are consistent with a model in which exhaustion of the proliferative capacity of naive T cells causes a sharp decline of their effective clonal diversity and imply that therapeutic potentiation of thymopoiesis might either prevent or reverse this outcome. Copyright © 2016 by The American Association of Immunologists, Inc.

  7. Evaluation of the impact of chitosan/DNA nanoparticles on the differentiation of human naive CD4{sup +} T cells

    Energy Technology Data Exchange (ETDEWEB)

    Liu Lanxia; Bai Yuanyuan; Zhu Dunwan; Song Liping; Wang Hai; Dong Xia; Zhang Hailing; Leng Xigang, E-mail: lengxg@bme.org.cn [Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin Key Laboratory of Biomedical Materials, Lab of Bioengineering, Institute of Biomedical Engineering (China)

    2011-06-15

    Chitosan (CS) is one of the most widely studied polymers in non-viral gene delivery since it is a cationic polysaccharide that forms nanoparticles with DNA and hence protects the DNA against digestion by DNase. However, the impact of CS/DNA nanoparticle on the immune system still remains poorly understood. Previous investigations did not found CS/DNA nanoparticles had any significant impact on the function of human and murine macrophages. To date, little is known about the interaction between CS/DNA nanoparticles and naive CD4{sup +} T cells. This study was designed to investigate whether CS/DNA nanoparticles affect the initial differentiation direction of human naive CD4{sup +} T cells. The indirect impact of CS/DNA nanoparticles on naive CD4{sup +} T cell differentiation was investigated by incubating the nanoparticles with human macrophage THP-1 cells in one chamber of a transwell co-incubation system, with the enriched human naive CD4{sup +} T cells being placed in the other chamber of the transwell. The nanoparticles were also co-incubated with the naive CD4{sup +} T cells to explore their direct impact on naive CD4{sup +} T cell differentiation by measuring the release of IL-4 and IFN-{gamma} from the cells. It was demonstrated that CS/DNA nanoparticles induced slightly elevated production of IL-12 by THP-1 cells, possibly owing to the presence of CpG motifs in the plasmid. However, this macrophage stimulating activity was much less significant as compared with lipopolysaccharide and did not impact on the differentiation of the naive CD4{sup +} T cells. It was also demonstrated that, when directly exposed to the naive CD4{sup +} T cells, the nanoparticles induced neither the activation of the naive CD4{sup +} T cells in the absence of recombinant cytokines (recombinant human IL-4 or IFN-{gamma}) that induce naive CD4{sup +} T cell polarization, nor any changes in the differentiation direction of naive CD4{sup +} T cells in the presence of the corresponding

  8. Three naive Bayes approaches for discrimination-free classification

    NARCIS (Netherlands)

    Calders, T.G.K.; Verwer, S.E.

    2010-01-01

    In this paper, we investigate how to modify the naive Bayes classifier in order to perform classification that is restricted to be independent with respect to a given sensitive attribute. Such independency restrictions occur naturally when the decision process leading to the labels in the data-set

  9. PERBANDINGAN K-NEAREST NEIGHBOR DAN NAIVE BAYES UNTUK KLASIFIKASI TANAH LAYAK TANAM POHON JATI

    Directory of Open Access Journals (Sweden)

    Didik Srianto

    2016-10-01

    Full Text Available Data mining adalah proses menganalisa data dari perspektif yang berbeda dan menyimpulkannya menjadi informasi-informasi penting yang dapat dipakai untuk meningkatkan keuntungan, memperkecil biaya pengeluaran, atau bahkan keduanya. Secara teknis, data mining dapat disebut sebagai proses untuk menemukan korelasi atau pola dari ratusan atau ribuan field dari sebuah relasional database yang besar. Pada perum perhutani KPH SEMARANG saat ini masih menggunakan cara manual untuk menentukan jenis tanaman (jati / non jati. K-Nearest Neighbour atau k-NN merupakan algoritma data mining yang dapat digunakan untuk proses klasifikasi dan regresi. Naive bayes Classifier merupakan suatu teknik yang dapat digunakan untuk teknik klasifikasi. Pada penelitian ini k-NN dan Naive Bayes akan digunakan untuk mengklasifikasi data pohon jati dari perum perhutani KPH SEMARANG. Yang mana hasil klasifikasi dari k-NN dan Naive Bayes akan dibandingkan hasilnya. Pengujian dilakukan menggunakan software RapidMiner. Setelah dilakukan pengujian k-NN dianggap lebih baik dari Naife Bayes dengan akurasi 96.66% dan 82.63. Kata kunci -k-NN,Klasifikasi,Naive Bayes,Penanaman Pohon Jati

  10. Incorporating pion effects into the naive quark model

    International Nuclear Information System (INIS)

    Nogami, Y.; Ohtuska, N.

    1982-01-01

    A hybrid of the naive nonrelativistic quark model and the Chew-Low model is proposed. The pion is treated as an elementary particle which interacts with the ''bare baryon'' or ''baryon core'' via the Chew-Low interaction. The baryon core, which is the source of the pion interaction, is described by the naive nonrelativistic quark model. It turns out that the baryon-core radius has to be as large as 0.8 fm, and consequently the cutoff momentum Λ for the pion interaction is < or approx. =3m/sub π/, m/sub π/ being the pion mass. Because of this small Λ (as compared with Λapprox. nucleon mass in the old Chew-Low model) the effects of the pion cloud are strongly suppressed. The baryon masses, baryon magnetic moments, and the nucleon charge radii can be reproduced quite well. However, we found it singularly difficult to fit the axial-vector weak decay constant g/sub A/

  11. Identification and characterization of the host protein DNAJC14 as a broadly active flavivirus replication modulator.

    Directory of Open Access Journals (Sweden)

    Zhigang Yi

    2011-01-01

    Full Text Available Viruses in the Flavivirus genus of the Flaviviridae family are arthropod-transmitted and contribute to staggering numbers of human infections and significant deaths annually across the globe. To identify cellular factors with antiviral activity against flaviviruses, we screened a cDNA library using an iterative approach. We identified a mammalian Hsp40 chaperone protein (DNAJC14 that when overexpressed was able to mediate protection from yellow fever virus (YFV-induced cell death. Further studies revealed that DNAJC14 inhibits YFV at the step of viral RNA replication. Since replication of bovine viral diarrhea virus (BVDV, a member of the related Pestivirus genus, is also known to be modulated by DNAJC14, we tested the effect of this host factor on diverse Flaviviridae family members. Flaviviruses, including the pathogenic Asibi strain of YFV, Kunjin, and tick-borne Langat virus, as well as a Hepacivirus, hepatitis C virus (HCV, all were inhibited by overexpression of DNAJC14. Mutagenesis showed that both the J-domain and the C-terminal domain, which mediates self-interaction, are required for anti-YFV activity. We found that DNAJC14 does not block YFV nor HCV NS2-3 cleavage, and using non-inhibitory mutants demonstrate that DNAJC14 is recruited to YFV replication complexes. Immunofluorescence analysis demonstrated that endogenous DNAJC14 rearranges during infection and is found in replication complexes identified by dsRNA staining. Interestingly, silencing of endogenous DNAJC14 results in impaired YFV replication suggesting a requirement for DNAJC14 in YFV replication complex assembly. Finally, the antiviral activity of overexpressed DNAJC14 occurs in a time- and dose-dependent manner. DNAJC14 overexpression may disrupt the proper stoichiometry resulting in inhibition, which can be overcome upon restoration of the optimal ratios due to the accumulation of viral nonstructural proteins. Our findings, together with previously published work

  12. The Role of Anti-Drug Antibodies in the Pharmacokinetics, Disposition, Target Engagement, and Efficacy of a GITR Agonist Monoclonal Antibody in Mice.

    Science.gov (United States)

    Brunn, Nicholas D; Mauze, Smita; Gu, Danling; Wiswell, Derek; Ueda, Roanna; Hodges, Douglas; Beebe, Amy M; Zhang, Shuli; Escandón, Enrique

    2016-03-01

    Administration of biologics to enhance T-cell function is part of a rapidly growing field of cancer immunotherapy demonstrated by the unprecedented clinical success of several immunoregulatory receptor targeting antibodies. While these biologic agents confer significant anti-tumor activity through targeted immune response modulation, they can also elicit broad immune responses potentially including the production of anti-drug antibodies (ADAs). DTA-1, an agonist monoclonal antibody against GITR, is a highly effective anti-tumor treatment in preclinical models. We demonstrate that repeated dosing with murinized DTA-1 (mDTA-1) generates ADAs with corresponding reductions in drug exposure and engagement of GITR on circulating CD3(+) CD4(+) T cells, due to rapid hepatic drug uptake and catabolism. Mice implanted with tumors after induction of preexisting mDTA-1 ADA show no anti-tumor efficacy when given 3 mg/kg mDTA-1, an efficacious dose in naive mice. Nonetheless, increasing mDTA-1 treatment to 30 mg/kg in ADA-positive mice restores mDTA-1 exposure and GITR engagement on circulating CD3(+) CD4(+) T cells, thereby partially restoring anti-tumor efficacy. Formation of anti-mDTA-1 antibodies and changes in drug exposure and disposition does not occur in GITR(-/-) mice, consistent with a role for GITR agonism in humoral immunity. Finally, the administration of muDX400, a murinized monoclonal antibody against the checkpoint inhibitor PD-1, dosed alone or combined with mDTA-1 did not result in reduced muDX400 exposure, nor did it change the nature of the anti-mDTA-1 response. This indicates that anti-GITR immunogenicity may not necessarily impact the pharmacology of coadministered monoclonal antibodies, supporting combination immunomodulatory strategies. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  13. Naive Bayesian classifiers for multinomial features: a theoretical analysis

    CSIR Research Space (South Africa)

    Van Dyk, E

    2007-11-01

    Full Text Available The authors investigate the use of naive Bayesian classifiers for multinomial feature spaces and derive error estimates for these classifiers. The error analysis is done by developing a mathematical model to estimate the probability density...

  14. New insights into flavivirus biology: the influence of pH over interactions between prM and E proteins

    Science.gov (United States)

    Oliveira, Edson R. A.; de Alencastro, Ricardo B.; Horta, Bruno A. C.

    2017-11-01

    Diseases caused by flaviviruses, such as dengue and zika, are globally recognized as major threats. During infection, a critical point in their replicative cycle is the maturation step, which occurs throughout the cellular exocytic pathway. This step is a pH-dependent process that involves the modification of the viral envelope by converting prM (pre-membrane) into M (membrane) proteins with the release of a "pr peptide". After this reaction, the pr peptides remain bound to the viral envelope while the virions cross the acidic trans-Golgi network, and are released only at neutral pH after secretion of the virus particles. Despite this current knowledge, the molecular basis of the flavivirus maturation step is largely unknown. Here, based on the crystal structure of the dengue pr-E complex ("pr peptide" bound to virus envelope protein) and using molecular dynamics simulations, we found that the pH shift from acidic to neutral yields considerable structural changes in the system. Dynamic cross correlation maps and root mean square deviation analyses revealed that the pr-E junction is clearly unstable under neutral pH. Secondary structure analysis also revealed that the fusion loop region, present in the E protein, is sensitive to pH and tends to unstructure at a neutral environment. Moreover, we found that five residues present in the E protein, Gly102, His244, Thr70, Thr68 and Asn67 are critical to confer stability to the pr-E complex while inside the Golgi apparatus. This work brings details about the dynamical behavior of the pr-E system, helps to better understand the flavivirus biology and may also be of use in the development of novel antiviral strategies.

  15. Generation and selection of naïve Fab library for parasitic antigen: Anti-BmSXP antibodies for lymphatic filariasis.

    Science.gov (United States)

    Omar, Noorsharmimi; Hamidon, Nurul Hamizah; Yunus, Muhammad Hafiznur; Noordin, Rahmah; Choong, Yee Siew; Lim, Theam Soon

    2018-05-01

    Phage display has been applied successfully as a tool for the generation of monoclonal antibodies (mAbs). Naive antibody libraries are unique as they are able to overcome several limitations associated with conventional mAb generation methods like the hybridoma technology. Here, we performed an in vitro selection and generation of Fab antibodies against Brugia malayi SXP protein (BmSXP), a recombinant antigen for the detection of lymphatic filariasis. We developed a naïve multi ethnic Fab antibody library with an estimated diversity of 2.99 × 10 9 . The antibody library was used to screen for mAbs against BmSXP recombinant antigen. Soluble monoclonal Fab antibodies against BmSXP were successfully isolated from the naïve library. The Fab antibodies obtained were expressed and analyzed to show its binding capability. The diversity obtained from a pool of donors from various ethnic groups allowed for a diverse antibody library to be generated. The mAbs obtained were also functional in soluble form, which makes it useful for further downstream applications. We believe that the Fab mAbs are valuable for further studies and could also contribute to improvements in the diagnosis of filariasis. © 2017 International Union of Biochemistry and Molecular Biology, Inc.

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

    OpenAIRE

    Hua, Rong-Hong; Chen, Na-Sha; Qin, Cheng-Feng; Deng, Yong-Qiang; Ge, Jin-Ying; Wang, Xi-Jun; Qiao, Zu-Jian; Chen, Wei-Ye; Wen, Zhi-Yuan; Liu, Wen-Xin; Hu, Sen; Bu, Zhi-Gao

    2010-01-01

    Abstract Background Differential diagnose of Japanese encephalitis virus (JEV) infection from other flavivirus especially West Nile virus (WNV) and Dengue virus (DV) infection was greatly hindered for the serological cross-reactive. Virus specific epitopes could benefit for developing JEV specific antibodies detection methods. To identify the JEV specific epitopes, we fully mapped and characterized the continuous B-cell epitope of the PrM/M protein of JEV. Results To map the epitopes on the P...

  17. Noncoding Subgenomic Flavivirus RNA: Multiple Functions in West Nile Virus Pathogenesis and Modulation of Host Responses

    Directory of Open Access Journals (Sweden)

    Justin A. Roby

    2014-01-01

    Full Text Available Flaviviruses are a large group of positive strand RNA viruses transmitted by arthropods that include many human pathogens such as West Nile virus (WNV, Japanese encephalitis virus (JEV, yellow fever virus, dengue virus, and tick-borne encephalitis virus. All members in this genus tested so far are shown to produce a unique subgenomic flavivirus RNA (sfRNA derived from the 3' untranslated region (UTR. sfRNA is a product of incomplete degradation of genomic RNA by the cell 5'–3' exoribonuclease XRN1 which stalls at highly ordered secondary RNA structures at the beginning of the 3'UTR. Generation of sfRNA results in inhibition of XRN1 activity leading to an increase in stability of many cellular mRNAs. Mutant WNV deficient in sfRNA generation was highly attenuated displaying a marked decrease in cytopathicity in cells and pathogenicity in mice. sfRNA has also been shown to inhibit the antiviral activity of IFN-α/β by yet unknown mechanism and of the RNAi pathway by likely serving as a decoy substrate for Dicer. Thus, sfRNA is involved in modulating multiple cellular pathways to facilitate viral pathogenicity; however the overlying mechanism linking all these multiple functions of sfRNA remains to be elucidated.

  18. Serological evidence of widespread exposure of Grenada fruit bats to chikungunya virus.

    Science.gov (United States)

    Stone, D; Lyons, A C; Huang, Y-J S; Vanlandingham, D L; Higgs, S; Blitvich, B J; Adesiyun, A A; Santana, S E; Leiser-Miller, L; Cheetham, S

    2018-03-25

    Antibody detection against selected potentially zoonotic vector-borne alphaviruses and flaviviruses was conducted on sera from bats from all six parishes in Grenada, West Indies. Sera were tested for (i) antibodies to flaviviruses West Nile virus, St. Louis encephalitis virus, Ilhéus virus, Bussuquara virus (BSQV), Rio Bravo virus and all four serotypes of dengue virus (DENV) by plaque reduction neutralization test (PRNT); (ii) antibodies to alphaviruses western equine encephalitis virus, Venezuelan equine encephalitis virus and eastern equine encephalitis virus by epitope-blocking enzyme-linked immunosorbent assay (ELISA); and (iii) antibodies to the alphavirus chikungunya (CHIKV) by PRNT. Two species of fruit bats were sampled, Artibeus jamaicensis and Artibeus lituratus, all roosting in or within 1,000 m of human settlements. Fifteen (36%) of the 42 bats tested for neutralizing antibodies to CHIKV were positive. The CHIKV-seropositive bats lived in localities spanning five of the six parishes. All 43 bats tested for epitope-blocking ELISA antibody to the other alphaviruses were negative, except one positive for Venezuelan equine encephalitis virus. All 50 bats tested for neutralizing antibody to flaviviruses were negative, except one that had a BSQV PRNT 80 titre of 20. The CHIKV serology results indicate that bats living close to and within human settlements were exposed to CHIKV in multiple locations. Importantly, bats for this study were trapped a year after the introduction and peak of the human CHIKV epidemic in Grenada. Thus, our data indicate that bats were exposed to CHIKV possibly during a time of marked decline in human cases. © 2018 Blackwell Verlag GmbH.

  19. Children's Conceptions of Mental Illness: A Naive Theory Approach

    Science.gov (United States)

    Fox, Claudine; Buchanan-Barrow, Eithne; Barrett, Martyn

    2010-01-01

    This paper reports two studies that investigated children's conceptions of mental illness using a naive theory approach, drawing upon a conceptual framework for analysing illness representations which distinguishes between the identity, causes, consequences, curability, and timeline of an illness. The studies utilized semi-structured interviewing…

  20. Neutralization Assay for Zika and Dengue Viruses by Use of Real-Time-PCR-Based Endpoint Assessment.

    Science.gov (United States)

    Wilson, Heather L; Tran, Thomas; Druce, Julian; Dupont-Rouzeyrol, Myrielle; Catton, Michael

    2017-10-01

    The global spread and infective complications of Zika virus (ZKV) and dengue virus (DENV) have made them flaviviruses of public health concern. Serological diagnosis can be challenging due to antibody cross-reactivity, particularly in secondary flavivirus infections or when there is a history of flavivirus vaccination. The virus neutralization assay is considered to be the most specific assay for measurement of anti-flavivirus antibodies. This study describes an assay where the neutralization endpoint is measured by real-time PCR, providing results within 72 h. It demonstrated 100% sensitivity (24/24 ZKV and 15/15 DENV) and 100% specificity (11/11 specimens) when testing well-characterized sera. In addition, the assay was able to determine the correct DENV serotype in 91.7% of cases. The high sensitivity and specificity of the real-time PCR neutralization assay makes it suitable to use as a confirmatory test for sera that are reactive in commercial IgM/IgG enzyme immunoassays. Results are objective and the PCR-based measurement of the neutralization endpoint lends itself to automation so that throughput may be increased in times of high demand. Copyright © 2017 American Society for Microbiology.

  1. Lymphatic endothelial S1P promotes mitochondrial function and survival in naive T cells.

    Science.gov (United States)

    Mendoza, Alejandra; Fang, Victoria; Chen, Cynthia; Serasinghe, Madhavika; Verma, Akanksha; Muller, James; Chaluvadi, V Sai; Dustin, Michael L; Hla, Timothy; Elemento, Olivier; Chipuk, Jerry E; Schwab, Susan R

    2017-06-01

    Effective adaptive immune responses require a large repertoire of naive T cells that migrate throughout the body, rapidly identifying almost any foreign peptide. Because the production of T cells declines with age, naive T cells must be long-lived. However, it remains unclear how naive T cells survive for years while constantly travelling. The chemoattractant sphingosine 1-phosphate (S1P) guides T cell circulation among secondary lymphoid organs, including spleen, lymph nodes and Peyer's patches, where T cells search for antigens. The concentration of S1P is higher in circulatory fluids than in lymphoid organs, and the S1P 1 receptor (S1P 1 R) directs the exit of T cells from the spleen into blood, and from lymph nodes and Peyer's patches into lymph. Here we show that S1P is essential not only for the circulation of naive T cells, but also for their survival. Using transgenic mouse models, we demonstrate that lymphatic endothelial cells support the survival of T cells by secreting S1P via the transporter SPNS2, that this S1P signals through S1P 1 R on T cells, and that the requirement for S1P 1 R is independent of the established role of the receptor in guiding exit from lymph nodes. S1P signalling maintains the mitochondrial content of naive T cells, providing cells with the energy to continue their constant migration. The S1P signalling pathway is being targeted therapeutically to inhibit autoreactive T cell trafficking, and these findings suggest that it may be possible simultaneously to target autoreactive or malignant cell survival.

  2. Detection of West Nile virus-specific antibodies and nucleic acid in horses and mosquitoes, respectively, in Nuevo Leon State, northern Mexico, 2006-2007.

    Science.gov (United States)

    Ibarra-Juarez, L; Eisen, L; Bolling, B G; Beaty, B J; Blitvich, B J; Sanchez-Casas, R M; Ayala-Sulca, Y O; Fernandez-Salas, I

    2012-09-01

    In the last 5 years, there has been only one reported human case of West Nile virus (WNV) disease in northern Mexico. To determine if the virus was still circulating in this region, equine and entomological surveillance for WNV was conducted in the state of Nuevo Leon in northern Mexico in 2006 and 2007. A total of 203 horses were serologically assayed for antibodies to WNV using an epitope-blocking enzyme-linked immunosorbent assay (bELISA). Seroprevalences for WNV in horses sampled in 2006 and 2007 were 26% and 45%, respectively. Mosquito collections in 2007 produced 7365 specimens representing 15 species. Culex mosquitoes were screened for WNV RNA and other genera (Mansonia, Anopheles, Aedes, Psorophora and Uranotaenia) were screened for flaviviruses using reverse-transcription (RT)-PCR. Two pools consisting of Culex spp. mosquitoes contained WNV RNA. Molecular species identification revealed that neither pool included Culex quinquefasciatus (Say) (Diptera:Culicidae) complex mosquitoes. No evidence of flaviviruses was found in the other mosquito genera examined. These data provide evidence that WNV is currently circulating in northern Mexico and that non-Cx. quinquefasciatus spp. mosquitoes may be participating in the WNV transmission cycle in this region. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

  3. Development and characterization of serotype-specific monoclonal antibodies against the dengue virus-4 (DENV-4) non-structural protein (NS1).

    Science.gov (United States)

    Gelanew, Tesfaye; Hunsperger, Elizabeth

    2018-02-06

    Dengue, caused by one of the four serologically distinct dengue viruses (DENV-1 to - 4), is a mosquito-borne disease of serious global health significance. Reliable and cost-effective diagnostic tests, along with effective vaccines and vector-control strategies, are highly required to reduce dengue morbidity and mortality. Evaluation studies revealed that many commercially available NS1 antigen (Ag) tests have limited sensitivity to DENV-4 serotype compared to the other three serotypes. These studies indicated the need for development of new NS1 Ag detection test with improved sensitivity to DENV-4. An NS1 capture enzyme linked immunoassay (ELISA) specific to DENV-4 may improve the detection of DENV-4 cases worldwide. In addition, a serotype-specific NS1 Ag test identifies both DENV and the infecting serotype. In this study, we used a small-ubiquitin-like modifier (SUMO*) cloning vector to express a SUMO*-DENV-4 rNS1 fusion protein to develop NS1 DENV-4 specific monoclonal antibodies (MAbs). These newly developed MAbs were then optimized for use in an anti-NS1 DENV-4 capture ELISA. The serotype specificity and sensitivity of this ELISA was evaluated using (i) supernatants from DENV (1-4)-infected Vero cell cultures, (ii) rNS1s from all the four DENV (1-4) and, (iii) rNS1s of related flaviviruses (yellow fever virus; YFV and West Nile virus; WNV). From the evaluation studies of the newly developed MAbs, we identified three DENV-4 specific anti-NS1 MAbs: 3H7A9, 8A6F2 and 6D4B10. Two of these MAbs were optimal for use in a DENV-4 serotype-specific NS1 capture ELISA: MAb 8A6F2 as the capture antibody and 6D4B10 as a detection antibody. This ELISA was sensitive and specific to DENV-4 with no cross-reactivity to other three DENV (1-3) serotypes and other heterologous flaviviruses. Taken together these data indicated that our MAbs are useful reagents for the development of DENV-4 immunodiagnostic tests.

  4. Studies on the antibody response of mice and humans after immunization with potential influenza virus A (H1N1) vaccines

    International Nuclear Information System (INIS)

    Poumbourios, P.; Jackson, D.C.; Oxford, J.S.

    1993-01-01

    The antibody response of mice and adult humans to immunization with subunit vaccines derived from a pair of antigenically distinct influenza A H1N1 viruses isolate in eggs was investigated. Although the haemagglutinin molecule of each virus differed by only three amino acid residues, highly specific antibody responses were elicited in mice as determined by haemagglutination inhibition and radioimmunoprecipitation assays. Results from competitive radioimmunoassays using monoclonal antibodies of known specificity and a study of the reactivity of mouse antisera with H1N1 field strains indicated that the marked differences in the antibody responses to the two vaccines was due to an amino acid substitution in the distal tip of the haemagglutinin molecule. In contrast, cross reactive antibody responses were elicited in humans presumably due to exposure to viruses related to the candidate vaccine prior to vaccination. Although immunogenic differences are apparent in this pair of antigenically distinct viruses in naive laboratory animals, these differences are not apparent following vaccination of humans that had prior exposure to related viruses. 21 refs., 5 tabs., 4 figs

  5. The Ras GTPase-activating protein Rasal3 supports survival of naive T cells.

    Directory of Open Access Journals (Sweden)

    Ryunosuke Muro

    Full Text Available The Ras-mitogen-activated protein kinase (MAPK pathway is crucial for T cell receptor (TCR signaling in the development and function of T cells. The significance of various modulators of the Ras-MAPK pathway in T cells, however, remains to be fully understood. Ras-activating protein-like 3 (Rasal3 is an uncharacterized member of the SynGAP family that contains a conserved Ras GTPase-activating protein (GAP domain, and is predominantly expressed in the T cell lineage. In the current study, we investigated the function and physiological roles of Rasal3. Our results showed that Rasal3 possesses RasGAP activity, but not Rap1GAP activity, and represses TCR-stimulated ERK phosphorylation in a T cell line. In systemic Rasal3-deficient mice, T cell development in the thymus including positive selection, negative selection, and β-selection was unaffected. However, the number of naive, but not effector memory CD4 and CD8 T cell in the periphery was significantly reduced in Rasal3-deficient mice, and associated with a marked increase in apoptosis of these cells. Indeed, survival of Rasal3 deficient naive CD4 T cells in vivo by adoptive transfer was significantly impaired, whereas IL-7-dependent survival of naive CD4 T cells in vitro was unaltered. Collectively, Rasal3 is required for in vivo survival of peripheral naive T cells, contributing to the maintenance of optimal T cell numbers.

  6. Epidemic dengue 2 in the city of Djibouti 1991-1992.

    Science.gov (United States)

    Rodier, G R; Gubler, D J; Cope, S E; Cropp, C B; Soliman, A K; Polycarpe, D; Abdourhaman, M A; Parra, J P; Maslin, J; Arthur, R R

    1996-01-01

    From October 1991 to February 1992, an outbreak of acute fever (in which thick blood films were negative for malaria) spread rapidly in the city of Djibouti, Djibouti Republic, affecting all age groups and both nationals and foreigners. The estimated number of cases was 12,000. The clinical features were consistent with a non-haemorrhagic dengue-like illness. Serum samples from 91 patients were analysed serologically for flavivirus infection (dengue 1-4, West Nile, yellow fever, Zika, Banzi, and Uganda-S), and virus isolation was attempted. Twelve strains of dengue 2 virus were isolated. Dengue infection was confirmed by a 4-fold or greater rise in immunoglobulin (Ig) G antibody in paired serum specimens, the presence of IgM antibody, or isolation of the virus. Overall, 46 of the suspected cases (51%) were confirmed virologically or had serological evidence of a recent flavivirus infection. Statistical analysis showed that the presence of a rash was the best predictor of flavivirus seropositivity. In November 1992, Aedes aegypti was widespread and abundant in several districts of Djibouti city. A serological study of serum samples collected from Djiboutian military personnel 5 months before the epidemic showed that only 15/177 (8.5%) had flavivirus antibodies. These findings, together with a negative serosurvey for dengue serotypes 1-4 and yellow fever virus performed in 1987, support the conclusion that dengue 2 virus has only recently been introduced to Djibouti.

  7. Detection of canine distemper virus serum neutralizing antibodies in captive U.S. phocids.

    Science.gov (United States)

    Clancy, Meredith M; Gamble, Kathryn C; Travis, Dominic A

    2013-03-01

    Antibodies to morbilliviruses have been documented in free-ranging pinnipeds throughout populations in the Atlantic and Arctic Oceans, but not from the Pacific Ocean. As a symbolic geographic barrier between the exposed Atlantic and naive Pacific populations, the captive phocid population in North America had undocumented serologic status. In this study, canine distemper virus (CDV) serum neutralization assays were used to assess the prevalence of antibodies in this population with participation of 25 U.S. institutions from grey seals (Halichoerus grypus, n = 6) and harbor seals (Phoca vitulina, n = 108). Historic and environmental risk factors associated with the epidemiology of distemper virus were collected by survey. Based on antibodies to canine distemper virus, the prevalence of exposure in this population was 25.5%, with 28 seals (grey, n = 2; harbor, n = 26) demonstrating antibody titers > or = 1:16, and positive titers ranged from 1:4 to 1:1,536. By survey analysis, strong associations with seropositive status were identified for captive origin (P = 0.013) and movement among institutions (P = 0.024). Size of population has positive correlation with likelihood of seropositive seals at an institution (P = 0.020). However, no major husbandry or enclosure-based risk factors were identified in institutions with seropositive seals, and no interaction between individual or institutional risk factors was identified. Previously undocumented prior to this study, CDV antibodies were measured in harbor seals (n = 2) recently stranded from the Pacific coast.

  8. Dealing with low pH: entry and exit of alphaviruses and flaviviruses.

    Science.gov (United States)

    Sánchez-San Martín, Claudia; Liu, Catherine Y; Kielian, Margaret

    2009-11-01

    The alphaviruses and flaviviruses include many important human pathogens, such as the dengue, West Nile, and Chikungunya viruses. These enveloped viruses infect cells by a membrane fusion reaction triggered by the low pH in endosomes. Fusion is mediated by viral membrane proteins through their acid-dependent conversion from a dimer on the virus surface to a homotrimer inserted into the host cell membrane. Here we review recent studies on the regulatory mechanisms that silence these fusion proteins during virus exit and that sense low pH and mediate protein refolding during virus entry. We discuss results using truncated proteins to dissect the fusion reaction, and future research directions including the development of antiviral therapies against these medically important viruses.

  9. Monitoring the initiation and kinetics of human dendritic cell-induced polarization of autologous naive CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Tammy Oth

    Full Text Available A crucial step in generating de novo immune responses is the polarization of naive cognate CD4+ T cells by pathogen-triggered dendritic cells (DC. In the human setting, standardized DC-dependent systems are lacking to study molecular events during the initiation of a naive CD4+ T cell response. We developed a TCR-restricted assay to compare different pathogen-triggered human DC for their capacities to instruct functional differentiation of autologous, naive CD4+ T cells. We demonstrated that this methodology can be applied to compare differently matured DC in terms of kinetics, direction, and magnitude of the naive CD4+ T cell response. Furthermore, we showed the applicability of this assay to study the T cell polarizing capacity of low-frequency blood-derived DC populations directly isolated ex vivo. This methodology for addressing APC-dependent instruction of naive CD4+ T cells in a human autologous setting will provide researchers with a valuable tool to gain more insight into molecular mechanisms occurring in the early phase of T cell polarization. In addition, it may also allow the study of pharmacological agents on DC-dependent T cell polarization in the human system.

  10. High affinity human antibody fragments to dengue virus non-structural protein 3.

    Directory of Open Access Journals (Sweden)

    Nicole J Moreland

    Full Text Available BACKGROUND: The enzyme activities catalysed by flavivirus non-structural protein 3 (NS3 are essential for virus replication. They are distributed between the N-terminal protease domain in the first one-third and the C-terminal ATPase/helicase and nucleoside 5' triphosphatase domain which forms the remainder of the 618-aa long protein. METHODOLOGY/PRINCIPAL FINDINGS: In this study, dengue full-length NS3 protein with residues 49 to 66 of NS2B covalently attached via a flexible linker, was used as bait in biopanning with a naïve human Fab phage-display library. Using a range of truncated constructs spanning the NS2B cofactor region and the full-length NS3, 10 unique Fab were identified and characterized. Of these, monoclonal Fab 3F8 was shown to bind α3″ (residues 526 through 531 within subdomain III of the helicase domain. The antibody inhibits the ATPase and helicase activites of NS3 in biochemical assays and reduces DENV replication in HEK293 cells that were previously transfected with Fab 3F8 compared with mock transfected cells. CONCLUSIONS/SIGNIFICANCE: Antibodies such as 3F8 are valuable tools for studying the molecular mechanisms of flaviviral replication and for the monospecific detection of replicating dengue virus in vivo.

  11. Efficacy and durability of nevirapine in antiretroviral drug naive patients

    NARCIS (Netherlands)

    Lange, Joep M. A.

    2003-01-01

    Nevirapine is a non-nucleoside reverse transcriptase inhibitor (NNRTI) that was first reported in the scientific literature in 1990. Varying doses of nevirapine (NVP) and a number of regimens containing this NNRTI have been studied in antiretroviral (ARV) naive patients. Four key studies have

  12. Naive (commonsense) geography and geobrowser usability after ten years of Google Earth

    Science.gov (United States)

    Hamerlinck, J. D.

    2016-04-01

    In 1995, the concept of ‘naive geography’ was formally introduced as an area of cognitive geographic information science representing ‘the body of knowledge that people have about the surrounding geographic world’ and reflecting ‘the way people think and reason about geographic space and time, both consciously and subconsciously’. The need to incorporate such commonsense knowledge and reasoning into design of geospatial technologies was identified but faced challenges in formalizing these relationships and processes in software implementation. Ten years later, the Google Earth geobrowser was released, marking the beginning of a new era of open access to, and application of, geographic data and information in society. Fast-forward to today, and the opportunity presents itself to take stock of twenty years of naive geography and a decade of the ubiquitous virtual globe. This paper introduces an ongoing research effort to explore the integration of naive (or commonsense) geography concepts in the Google Earth geobrowser virtual globe and their possible impact on Google Earth's usability, utility, and usefulness. A multi-phase methodology is described, combining usability reviews and usability testing with use-case scenarios involving the U.S.-Canadian Yellowstone to Yukon Initiative. Initial progress on a usability review combining cognitive walkthroughs and heuristics evaluation is presented.

  13. Ensemble of Chaotic and Naive Approaches for Performance Enhancement in Video Encryption

    Directory of Open Access Journals (Sweden)

    Jeyamala Chandrasekaran

    2015-01-01

    Full Text Available Owing to the growth of high performance network technologies, multimedia applications over the Internet are increasing exponentially. Applications like video conferencing, video-on-demand, and pay-per-view depend upon encryption algorithms for providing confidentiality. Video communication is characterized by distinct features such as large volume, high redundancy between adjacent frames, video codec compliance, syntax compliance, and application specific requirements. Naive approaches for video encryption encrypt the entire video stream with conventional text based cryptographic algorithms. Although naive approaches are the most secure for video encryption, the computational cost associated with them is very high. This research work aims at enhancing the speed of naive approaches through chaos based S-box design. Chaotic equations are popularly known for randomness, extreme sensitivity to initial conditions, and ergodicity. The proposed methodology employs two-dimensional discrete Henon map for (i generation of dynamic and key-dependent S-box that could be integrated with symmetric algorithms like Blowfish and Data Encryption Standard (DES and (ii generation of one-time keys for simple substitution ciphers. The proposed design is tested for randomness, nonlinearity, avalanche effect, bit independence criterion, and key sensitivity. Experimental results confirm that chaos based S-box design and key generation significantly reduce the computational cost of video encryption with no compromise in security.

  14. Three Naive Questions: Addressed to the Modern Educational Optimism

    Science.gov (United States)

    Krstic, Predrag

    2016-01-01

    This paper aims to question anew the popular and supposedly self-evident affirmation of education, in its modern incarnation as in its historical notion. The "naive" questions suggest that we have recently taken for granted that education ought to be for the masses, that it ought to be upbringing, and that it is better than ignorance.…

  15. Naive forecasting: the fiasco of coal gasification

    Energy Technology Data Exchange (ETDEWEB)

    Peirce, W S

    1985-01-01

    The decision by the U.S. government to subsidize the development of coal gasification was based on a naive forecast that neglected the influence of price on both conventional sources of supply and consumer demand. Even before substantial construction costs were incurred on the Great Plains plant, a surplus of natural gas has developed. The political process, however, did not include the sort of critical review that often accompanies the financing decision in the private sector and that would surely have prevented this error. 17 references.

  16. Comparative Analysis Between Flaviviruses Reveals Specific Neural Stem Cell Tropism for Zika Virus in the Mouse Developing Neocortex

    Directory of Open Access Journals (Sweden)

    Jean-Baptiste Brault

    2016-08-01

    Full Text Available The recent Zika outbreak in South America and French Polynesia was associated with an epidemic of microcephaly, a disease characterized by a reduced size of the cerebral cortex. Other members of the Flavivirus genus, including West Nile virus (WNV, can cause encephalitis but were not demonstrated to cause microcephaly. It remains unclear whether Zika virus (ZIKV and other flaviviruses may infect different cell populations in the developing neocortex and lead to distinct developmental defects. Here, we describe an assay to infect mouse E15 embryonic brain slices with ZIKV, WNV and dengue virus serotype 4 (DENV-4. We show that this tissue is able to support viral replication of ZIKV and WNV, but not DENV-4. Cell fate analysis reveals a remarkable tropism of ZIKV infection for neural stem cells. Closely related WNV displays a very different tropism of infection, with a bias towards neurons. We further show that ZIKV infection, but not WNV infection, impairs cell cycle progression of neural stem cells. Both viruses inhibited apoptosis at early stages of infection. This work establishes a powerful comparative approach to identify ZIKV-specific alterations in the developing neocortex and reveals specific preferential infection of neural stem cells by ZIKV.

  17. 1,25-dihydroxyvitamin D3 impairs NF-κB activation in human naive B cells

    International Nuclear Information System (INIS)

    Geldmeyer-Hilt, Kerstin; Heine, Guido; Hartmann, Bjoern; Baumgrass, Ria; Radbruch, Andreas; Worm, Margitta

    2011-01-01

    Highlights: → In naive B cells, VDR activation by calcitriol results in reduced NF-κB p105 and p50 protein expression. → Ligating the VDR with calcitriol causes reduced nuclear translocation of NF-κB p65. → Reduced nuclear amount of p65 after calcitriol incubation results in reduced binding of p65 on the p105 promoter. → Thus, vitamin D receptor signaling may reduce or prevent activation of B cells and unwanted immune responses, e.g. in IgE dependent diseases such as allergic asthma. -- Abstract: 1α,25-dihydroxyvitamin D 3 (calcitriol), the bioactive metabolite of vitamin D, modulates the activation and inhibits IgE production of anti-CD40 and IL-4 stimulated human peripheral B cells. Engagement of CD40 results in NF-κB p50 activation, which is essential for the class switch to IgE. Herein, we investigated by which mechanism calcitriol modulates NF-κB mediated activation of human naive B cells. Naive B cells were predominantly targeted by calcitriol in comparison with memory B cells as shown by pronounced induction of the VDR target gene cyp24a1. Vitamin D receptor activation resulted in a strongly reduced p105/p50 protein and mRNA expression in human naive B cells. This effect is mediated by impaired nuclear translocation of p65 and consequently reduced binding of p65 to its binding site in the p105 promoter. Our data indicate that the vitamin D receptor reduces NF-κB activation by interference with NF-κB p65 and p105. Thus, the vitamin D receptor inhibits costimulatory signal transduction in naive B cells, namely by reducing CD40 signaling.

  18. Stability of a tick-borne flavivirus in milk

    Directory of Open Access Journals (Sweden)

    Danielle K Offerdahl

    2016-05-01

    Full Text Available The tick-borne flaviviruses (TBFV occur worldwide and the tick-borne encephalitis virus members of the group (TBEV often cause severe, debilitating neurological disease in humans. Although the primary route of infection is through the bite of an infected tick, alimentary infection through the consumption of TBEV-contaminated dairy products is also well-documented and is responsible for some disease in endemic areas. Experimental infection of goats, cattle, and sheep with TBEV shows that virus can be excreted in the milk of infected animals. Additionally, the virus remains infectious after exposure to low pH levels, similar to those found in the stomach. To evaluate survival of virus in milk, we studied the stability of the BSL-2 TBFV, Langat virus, in unpasteurized goat milk over time and after different thermal treatments. Virus was stable in milk maintained under refrigeration conditions; however, there was a marked reduction in virus titer after incubation at room temperature. High temperature, short time pasteurization protocols completely inactivated the virus. Interestingly, simulation of a typical thermal regime utilized for cheese did not completely inactivate the virus in milk. These findings stress the importance of proper milk handling and pasteurization processes in areas endemic for TBEV.

  19. Stability of a Tick-Borne Flavivirus in Milk.

    Science.gov (United States)

    Offerdahl, Danielle K; Clancy, Niall G; Bloom, Marshall E

    2016-01-01

    The tick-borne flaviviruses (TBFV) occur worldwide and the tick-borne encephalitis virus (TBEV) members of the group often cause severe, debilitating neurological disease in humans. Although the primary route of infection is through the bite of an infected tick, alimentary infection through the consumption of TBEV-contaminated dairy products is also well-documented and is responsible for some disease in endemic areas. Experimental infection of goats, cattle, and sheep with TBEV shows that the virus can be excreted in the milk of infected animals. Additionally, the virus remains infectious after exposure to low pH levels, similar to those found in the stomach. To evaluate the survival of virus in milk, we studied the stability of the BSL-2 TBFV, Langat virus, in unpasteurized goat milk over time and after different thermal treatments. Virus was stable in milk maintained under refrigeration conditions; however, there was a marked reduction in virus titer after incubation at room temperature. High temperature, short time pasteurization protocols completely inactivated the virus. Interestingly, simulation of a typical thermal regime utilized for cheese did not completely inactivate the virus in milk. These findings stress the importance of proper milk handling and pasteurization processes in areas endemic for TBEV.

  20. Results of the naive quark model

    International Nuclear Information System (INIS)

    Gignoux, C.

    1987-10-01

    The hypotheses and limits of the naive quark model are recalled and results on nucleon-nucleon scattering and possible multiquark states are presented. Results show that with this model, ropers do not come. For hadron-hadron interactions, the model predicts Van der Waals forces that the resonance group method does not allow. Known many-body forces are not found in the model. The lack of mesons shows up in the absence of a far reaching force. However, the model does have strengths. It is free from spuriousness of center of mass, and allows a democratic handling of flavor. It has few parameters, and its predictions are very good [fr

  1. The naive CD4+ count in HIV-1-infected patients at time of initiation of highly active antiretroviral therapy is strongly associated with the level of immunological recovery

    DEFF Research Database (Denmark)

    Michael, OG; Kirk, O; Mathiesen, Lars Reinhardt

    2002-01-01

    CD4 + count followed a triphasic pattern, reflecting an initial phase of rapid redistribution from lymphoid tissues, followed by a slow increase, partially due to an increase in naive CD4+ cell count. From Month 18 onwards, both naive and total CD4 + cell counts stabilized, although viral suppression......-infected patients. The focus was on the naive CD4 + cell time course and associations between naive CD4 + cell counts and established prognostic markers. Total and naive CD4 + cell counts were measured using flow cytometry. The HIV-RNA detection limit was 20 copies/ml. During 36 months of HAART, the total...... was sustained. There was no association between plasma viral load and the increase in naive CD4 + cell count. Importantly, baseline naive CD4 + cell count was significantly associated with the change in naive CD4 + cell count, suggesting that the naive cell count at baseline does influence the immunological...

  2. {sup 68}Ga-labelled recombinant antibody variants for immuno-PET imaging of solid tumours

    Energy Technology Data Exchange (ETDEWEB)

    Eder, Matthias; Eisenhut, Michael [German Cancer Research Center, Radiopharmaceutical Chemistry, Heidelberg (Germany); Knackmuss, Stefan; Gall, Fabrice Le; Reusch, Uwe; Little, Melvyn [Affimed Therapeutics AG, Heidelberg (Germany); Rybin, Vladimir [European Molecular Biology Laboratory, Heidelberg (Germany); Haberkorn, Uwe; Mier, Walter [University of Heidelberg, Department of Nuclear Medicine, Heidelberg (Germany)

    2010-07-15

    Recombinant antibodies isolated from human antibody libraries have excellent affinities and high target specificity. As full-length IgGs are cleared inadequately slowly from the circulation, the aim of this work was to figure out which kind of recombinant antibody fragment proves to be appropriate for imaging epithelial cell adhesion molecule (EpCAM)-expressing tumours with the short-living radioisotope {sup 68}Ga. In order to combine the promising tumour targeting properties of antibodies with {sup 68}Ga, four antibody variants with the same specificity and origin only differing in molecular weight were constructed for comparison. Therefore, the binding domains of a single-chain fragment variable (scFv) isolated from a human naive antibody library were modified genetically to construct the respective full-length IgG, the tria- and diabody variants. These molecules were conjugated with the bifunctional chelating agent N,N{sup '}-bis[2-hydroxy-5-(carboxyethyl)benzyl]ethylenediamine-N,N{sup '}-diacetic acid (HBED-CC) to enable {sup 68}Ga labelling at ambient temperature and compared in biodistribution and immuno-PET imaging experiments. The antibody variants with identical specificity proved to have the correct molecular weight, high binding affinity and specificity to their antigen, EpCAM. Radiometal complexation was efficiently performed at room temperature leading to {sup 68}Ga-labelled antibodies with unchanged binding properties compared to the original antibody variants. The best targeting properties were obtained with the scFv and especially with the diabody. The triabody showed higher absolute tumour uptake but only moderate clearance from circulation. The antibody variants differed considerably in normal organ uptake, clearance from circulation and tumour accumulation. The data demonstrate the feasibility of imaging solid tumours with the {sup 68}Ga-labelled diabody format. This type of recombinant protein might be a promising carrier even for the

  3. Decreased naive and increased memory CD4(+ T cells are associated with subclinical atherosclerosis: the multi-ethnic study of atherosclerosis.

    Directory of Open Access Journals (Sweden)

    Nels C Olson

    Full Text Available Adaptive immunity has been implicated in atherosclerosis in animal models and small clinical studies. Whether chronic immune activation is associated with atherosclerosis in otherwise healthy individuals remains underexplored. We hypothesized that activation of adaptive immune responses, as reflected by higher proportions of circulating CD4(+ memory cells and lower proportions of naive cells, would be associated with subclinical atherosclerosis.We examined cross-sectional relationships of circulating CD4(+ naive and memory T cells with biomarkers of inflammation, serologies, and subclinical atherosclerosis in 912 participants of the Multi-Ethnic Study of Atherosclerosis (MESA. Circulating CD4(+ naive cells were higher in women than men and decreased with age (all p-values <0.0001. European-Americans had higher levels of naive cells and lower levels of memory cells compared with African-Americans and Hispanic-Americans (all p-values ≤0.0005. Lower naive/higher memory cells were associated with interleukin-6 levels. In multivariate models, cytomegalovirus (CMV and H. Pylori titers were strongly associated with higher memory and lower naive cells (all p-values <0.05. Higher memory cells were associated with coronary artery calcification (CAC level in the overall population [β-Coefficient (95% confidence interval (CI  = 0.20 (0.03, 0.37]. Memory and naive (inversely cells were associated with common carotid artery intimal media thickness (CC IMT in European-Americans [memory: β =  0.02 (0.006, 0.04; naive: β = -0.02 (-0.004, -0.03].These results demonstrate that the degree of chronic adaptive immune activation is associated with both CAC and CC IMT in otherwise healthy individuals, consistent with the known role of CD4(+ T cells, and with innate immunity (inflammation, in atherosclerosis. These data are also consistent with the hypothesis that immunosenescence accelerates chronic diseases by putting a greater burden on the innate

  4. Binary naive Bayesian classifiers for correlated Gaussian features: a theoretical analysis

    CSIR Research Space (South Africa)

    Van Dyk, E

    2008-11-01

    Full Text Available classifier with Gaussian features while using any quadratic decision boundary. Therefore, the analysis is not restricted to Naive Bayesian classifiers alone and can, for instance, be used to calculate the Bayes error performance. We compare the analytical...

  5. Expert and Naive Raters Using the PAG: Does it Matter?

    Science.gov (United States)

    Cornelius, Edwin T.; And Others

    1984-01-01

    Questions the observed correlation between job experts and naive raters using the Position Analysis Questionnaire (PAQ); and conducts a replication of the Smith and Hakel study (1979) with college students (N=39). Concluded that PAQ ratings from job experts and college students are not equivalent and therefore are not interchangeable. (LLL)

  6. Right lateralized white matter abnormalities in first-episode, drug-naive paranoid schizophrenia.

    Science.gov (United States)

    Guo, Wenbin; Liu, Feng; Liu, Zhening; Gao, Keming; Xiao, Changqing; Chen, Huafu; Zhao, Jingping

    2012-11-30

    Numerous studies in first-episode schizophrenia suggest the involvement of white matter (WM) abnormalities in multiple regions underlying the pathogenesis of this condition. However, there has never been a neuroimaging study in patients with first-episode, drug-naive paranoid schizophrenia by using tract-based spatial statistics (TBSS) method. Here, we used diffusion tensor imaging (DTI) with TBSS method to investigate the brain WM integrity in patients with first-episode, drug-naive paranoid schizophrenia. Twenty patients with first-episode, drug-naive paranoid schizophrenia and 26 healthy subjects matched with age, gender, and education level were scanned with DTI. An automated TBSS approach was employed to analyze the data. Voxel-wise statistics revealed that patients with paranoid schizophrenia had decreased fractional anisotropy (FA) values in the right superior longitudinal fasciculus (SLF) II, the right fornix, the right internal capsule, and the right external capsule compared to healthy subjects. Patients did not have increased FA values in any brain regions compared to healthy subjects. There was no correlation between the FA values in any brain regions and patient demographics and the severity of illness. Our findings suggest right-sided alterations of WM integrity in the WM tracts of cortical and subcortical regions may play an important role in the pathogenesis of paranoid schizophrenia. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  7. Transmission of West Nile virus by Culex quinquefasciatus say infected with Culex Flavivirus Izabal.

    Directory of Open Access Journals (Sweden)

    Rebekah J Kent

    Full Text Available BACKGROUND: The natural history and potential impact of mosquito-specific flaviviruses on the transmission efficiency of West Nile virus (WNV is unknown. The objective of this study was to determine whether or not prior infection with Culex flavivirus (CxFV Izabal altered the vector competence of Cx. quinquefasciatus Say for transmission of a co-circulating strain of West Nile virus (WNV from Guatemala. METHODS AND FINDINGS: CxFV-negative Culex quinquefasciatus and those infected with CxFV Izabal by intrathoracic inoculation were administered WNV-infectious blood meals. Infection, dissemination, and transmission of WNV were measured by plaque titration on Vero cells of individual mosquito bodies, legs, or saliva, respectively, two weeks following WNV exposure. Additional groups of Cx. quinquefasciatus were intrathoracically inoculated with WNV alone or WNV+CxFV Izabal simultaneously, and saliva collected nine days post inoculation. Growth of WNV in Aedes albopictus C6/36 cells or Cx. quinquefasciatus was not inhibited by prior infection with CxFV Izabal. There was no significant difference in the vector competence of Cx. quinquefasciatus for WNV between mosquitoes uninfected or infected with CxFV Izabal across multiple WNV blood meal titers and two colonies of Cx. quinquefasciatus (p>0.05. However, significantly more Cx. quinquefasciatus from Honduras that were co-inoculated simultaneously with both viruses transmitted WNV than those inoculated with WNV alone (p = 0.0014. Co-inoculated mosquitoes that transmitted WNV also contained CxFV in their saliva, whereas mosquitoes inoculated with CxFV alone did not contain virus in their saliva. CONCLUSIONS: In the sequential infection experiments, prior infection with CxFV Izabal had no significant impact on WNV replication, infection, dissemination, or transmission by Cx. quinquefasciatus, however WNV transmission was enhanced in the Honduras colony when mosquitoes were inoculated simultaneously with

  8. Naive and effector B-cell subtypes are increased in chronic rhinosinusitis with polyps.

    Science.gov (United States)

    Miljkovic, Dijana; Psaltis, Alkis; Wormald, Peter-John; Vreugde, Sarah

    2018-01-01

    Recent studies demonstrated that B cells and their chemoattractants are elevated in the nasal mucosa of patients with chronic rhinosinusitis (CRS) with nasal polyposis (CRSwNP). However, the presence of naive B cells and of plasmablasts and memory B-cell subsets in the mucosa and periphery of the same patient with CRS is yet to be characterized. Here we sought to quantify naive, plasmablasts, and memory B cells in mucosal tissue and peripheral blood of patients with CRSwNP, patients with CRS without nasal polyps (CRSsNP), and control patients. Polyps, mucosa, and peripheral blood samples were prospectively collected from the patients with CRS and from the non-CRS controls. We used flow cytometry to distinguish among naive, plasmablast, and memory B cells in sinus tissue and peripheral blood. A total of 45 patients were recruited for the study. The patients with CRSwNP had significantly increased mucosal B-cell numbers versus the controls (3.39 ± 4.05% versus 0.39 ± 1.05% of live cells; p Kruskal-Wallis test), which included naive B cells (0.61 ± 0.94 versus 0.11 ± 0.24% of live cells; p Kruskal-Wallis test), plasmablasts (0.06 ± 0.26 versus 0.00 ± 0.00% of live cells; p Kruskal-Wallis test), and memory B cells (0.62 ± 1.26 versus 0.05 ± 0.15% of live cells; p Kruskal-Wallis test). Our study identified increased frequencies of different B-cell subtypes in the mucosa of patients with CRSwNP but not in the peripheral blood. We also found that patients with CRSwNP had significantly increased B-cell subtypes compared with the patients with CRSsNP and the controls. These results implied a potential role for mucosal B cells in the ongoing inflammation in patients with CRSwNP.

  9. Tick-borne encephalitis virus neutralization by high dose intravenous immunoglobulin

    Czech Academy of Sciences Publication Activity Database

    Elsterová, Jana; Palus, Martin; Širmarová, J.; Kopecký, J.; Niller, H.H.; Růžek, Daniel

    2017-01-01

    Roč. 8, č. 2 (2017), s. 253-258 ISSN 1877-959X R&D Projects: GA MZd(CZ) NV16-34238A Institutional support: RVO:60077344 Keywords : flavivirus * ticks * neutralizing antibodies * ivig * antibody-dependent enhancement * ammunotherapy Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.230, year: 2016

  10. Associations between vascular co-morbidities and depression in insulin-naive diabetes patients

    DEFF Research Database (Denmark)

    Koopmans, B; Pouwer, F; de Bie, Rob A

    2009-01-01

    AIMS/HYPOTHESIS: The aim of the study was to determine the prevalence of depression in insulin-naive diabetes patients and to investigate the associations between different forms of vascular co-morbidity and depression. METHODS: Cross-sectional data were used from a primary-care sample of 1......,269 insulin-naive (i.e. not using insulin therapy) diabetes patients participating in the DIAZOB Primary Care Diabetes study. Demographics, vascular co-morbidities, clinical and lifestyle characteristics, and psychosocial factors were assessed. Depression symptoms were measured with the Edinburgh Depression.......2% vs 10.0%). Single vascular co-morbidities were not associated with increased rates of depression. The final model predicting depression included: having multiple vascular co-morbidities compared with none; having less social support; having experienced a recent stressful life event; female sex...

  11. 1,25-dihydroxyvitamin D{sub 3} impairs NF-{kappa}B activation in human naive B cells

    Energy Technology Data Exchange (ETDEWEB)

    Geldmeyer-Hilt, Kerstin, E-mail: kerstin.hilt@charite.de [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany); Heine, Guido, E-mail: guido.heine@charite.de [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany); Deutsches Rheuma-Forschungszentrum Berlin, Chariteplatz 1, 10117 Berlin (Germany); Hartmann, Bjoern, E-mail: bjoern.hartmann@charite.de [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany); Baumgrass, Ria, E-mail: baumgrass@drfz.de [Deutsches Rheuma-Forschungszentrum Berlin, Chariteplatz 1, 10117 Berlin (Germany); Radbruch, Andreas, E-mail: radbruch@drfz.de [Deutsches Rheuma-Forschungszentrum Berlin, Chariteplatz 1, 10117 Berlin (Germany); Worm, Margitta, E-mail: margitta.worm@charite.de [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany)

    2011-04-22

    Highlights: {yields} In naive B cells, VDR activation by calcitriol results in reduced NF-{kappa}B p105 and p50 protein expression. {yields} Ligating the VDR with calcitriol causes reduced nuclear translocation of NF-{kappa}B p65. {yields} Reduced nuclear amount of p65 after calcitriol incubation results in reduced binding of p65 on the p105 promoter. {yields} Thus, vitamin D receptor signaling may reduce or prevent activation of B cells and unwanted immune responses, e.g. in IgE dependent diseases such as allergic asthma. -- Abstract: 1{alpha},25-dihydroxyvitamin D{sub 3} (calcitriol), the bioactive metabolite of vitamin D, modulates the activation and inhibits IgE production of anti-CD40 and IL-4 stimulated human peripheral B cells. Engagement of CD40 results in NF-{kappa}B p50 activation, which is essential for the class switch to IgE. Herein, we investigated by which mechanism calcitriol modulates NF-{kappa}B mediated activation of human naive B cells. Naive B cells were predominantly targeted by calcitriol in comparison with memory B cells as shown by pronounced induction of the VDR target gene cyp24a1. Vitamin D receptor activation resulted in a strongly reduced p105/p50 protein and mRNA expression in human naive B cells. This effect is mediated by impaired nuclear translocation of p65 and consequently reduced binding of p65 to its binding site in the p105 promoter. Our data indicate that the vitamin D receptor reduces NF-{kappa}B activation by interference with NF-{kappa}B p65 and p105. Thus, the vitamin D receptor inhibits costimulatory signal transduction in naive B cells, namely by reducing CD40 signaling.

  12. Multi criteria wrapper improvements to naive bayes learning

    OpenAIRE

    Cortizo Pérez, José Carlos; Giráldez Betrón, Juan Ignacio

    2006-01-01

    Feature subset selection using a wrapper means to perform a search for an optimal set of attributes using the Machine Learning Algorithm as a black box. The Naive Bayes Classifier is based on the assumption of independence among the values of the attributes given the class value. Consequently, its effectiveness may decrease when the attributes are interdependent. We present FBL, a wrapper that uses information about dependencies to guide the search for the optimal subset of features and we us...

  13. Lipid Profile of Anti Retroviral Treatment Naive HIV Infected Patients ...

    African Journals Online (AJOL)

    hypercholesterolemia [22.4% (22/98) vs. 10.4% (11/106), P = 0.02]. Lower HDL.C was associated with CD4+ cell count < 200 cells/ƒÊL (P = 0.02). Conclusion: Lipid abnormalities are common in treatment.naive HIV.infected patients even in the absence of major host.related risk factors for dyslipidemia. HIV.infected patients ...

  14. A Workshop for High School Students on Naive Set Theory

    Science.gov (United States)

    Wegner, Sven-Ake

    2014-01-01

    In this article we present the prototype of a workshop on naive set theory designed for high school students in or around the seventh year of primary education. Our concept is based on two events which the author organized in 2006 and 2010 for students of elementary school and high school, respectively. The article also includes a practice report…

  15. Safety and efficacy of tiotropium Respimat versus HandiHaler in patients naive to treatment with inhaled anticholinergics

    DEFF Research Database (Denmark)

    Wise, Robert; Calverley, Peter Ma; Dahl, Ronald

    2015-01-01

    BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) who were naive to anticholinergics before the TIOtropium Safety and Performance In Respimat (TIOSPIR) trial may reflect patients seen in practice, in particular in primary care. In addition, investigating safety...... in these patients avoids the potential bias in patients who previously received anticholinergics and may be tolerant of their effects. AIMS: The aim of this study was to evaluate whether patients naive to anticholinergic therapy who were treated with tiotropium Respimat 2.5 or 5 μg had different safety and efficacy...... the Respimat and HandiHaler groups. Rates of exacerbations in the subgroup of patients with moderate disease were similar across the Respimat and HandiHaler groups. CONCLUSIONS: Tiotropium Respimat and HandiHaler have similar safety and efficacy profiles in patients who are naive to anticholinergic therapy....

  16. Short-lived brain state after cued motor imagery in naive subjects

    NARCIS (Netherlands)

    Pfurtscheller, G.; Scherer, R.; Müller-Putz, G.R.; Lopes da Silva, F.H.

    2008-01-01

    Multi-channel electroencephalography recordings have shown that a visual cue, indicating right hand, left hand or foot motor imagery, can induce a short-lived brain state in the order of about 500 ms. In the present study, 10 able-bodied subjects without any motor imagery experience (naive subjects)

  17. Role of antibodies in controlling dengue virus infection

    NARCIS (Netherlands)

    van der Schaar, Hilde M.; Wilschut, Jan C.; Smit, Jolanda M.

    The incidence and disease burden of arthropod-borne flavivirus infections have dramatically increased during the last decades due to major societal and economic changes, including massive urbanization, lack of vector control, travel, and international trade. Specifically, in the case of dengue virus

  18. Hepatitis C virus NS3 protein polynucleotide-stimulated nucleoside triphosphatase and comparison with the related pestivirus and flavivirus enzymes.

    Science.gov (United States)

    Suzich, J A; Tamura, J K; Palmer-Hill, F; Warrener, P; Grakoui, A; Rice, C M; Feinstone, S M; Collett, M S

    1993-01-01

    Sequence motifs within the nonstructural protein NS3 of members of the Flaviviridae family suggest that this protein possesses nucleoside triphosphatase (NTPase) and RNA helicase activity. The RNA-stimulated NTPase activity of this protein from prototypic members of the Pestivirus and Flavivirus genera has recently been established and enzymologically characterized. Here, we experimentally demonstrate that the NS3 protein from a member of the third genus of Flaviviridae, human hepatitis C virus (HCV), also possesses a polynucleotide-stimulated NTPase activity. Characterization of the purified HCV NTPase activity showed that it exhibited reaction condition optima with respect to pH, MgCl2, and salt identical to those of the representative pestivirus and flavivirus enzymes. However, each NTPase also possessed several unique properties when compared with one another. Notably, the profile of polynucleotide stimulation of the NTPase activity was distinct for the three enzymes. The HCV NTPase was the only one whose activity was significantly enhanced by a deoxyribopolynucleotide. Additional distinguishing features among the three enzymes relating to the kinetic properties of their NTPase activities are discussed. These studies provide a foundation for investigation of the putative RNA helicase activity of these proteins and for further study of the role of the NS3 proteins of members of the Flaviviridae in the replication cycle of these viruses. Images PMID:8396675

  19. Accuracy Evaluation of C4.5 and Naive Bayes Classifiers Using Attribute Ranking Method

    Directory of Open Access Journals (Sweden)

    S. Sivakumari

    2009-03-01

    Full Text Available This paper intends to classify the Ljubljana Breast Cancer dataset using C4.5 Decision Tree and Nai?ve Bayes classifiers. In this work, classification is carriedout using two methods. In the first method, dataset is analysed using all the attributes in the dataset. In the second method, attributes are ranked using information gain ranking technique and only the high ranked attributes are used to build the classification model. We are evaluating the results of C4.5 Decision Tree and Nai?ve Bayes classifiers in terms of classifier accuracy for various folds of cross validation. Our results show that both the classifiers achieve good accuracy on the dataset.

  20. Robust Biometric Score Fusion by Naive Likelihood Ratio via Receiver Operating Characteristics

    NARCIS (Netherlands)

    Tao, Q.; Veldhuis, Raymond N.J.

    This paper presents a novel method of fusing multiple biometrics on the matching score level. We estimate the likelihood ratios of the fused biometric scores, via individual receiver operating characteristics (ROC) which construct the Naive Bayes classifier. Using a limited number of operation

  1. Duration of antibody response following vaccination against feline immunodeficiency virus.

    Science.gov (United States)

    Westman, Mark E; Malik, Richard; Hall, Evelyn; Harris, Matthew; Hosie, Margaret J; Norris, Jacqueline M

    2017-10-01

    Objectives Recently, two point-of-care (PoC) feline immunodeficiency virus (FIV) antibody test kits (Witness and Anigen Rapid) were reported as being able to differentiate FIV-vaccinated from FIV-infected cats at a single time point, irrespective of the gap between testing and last vaccination (0-7 years). The aim of the current study was to investigate systematically anti-FIV antibody production over time in response to the recommended primary FIV vaccination series. Methods First, residual plasma from the original study was tested using a laboratory-based ELISA to determine whether negative results with PoC testing were due to reduced as opposed to absent antibodies to gp40. Second, a prospective study was performed using immunologically naive client-owned kittens and cats given a primary FIV vaccination series using a commercially available inactivated whole cell/inactivated whole virus vaccine (Fel-O-Vax FIV, three subcutaneous injections at 4 week intervals) and tested systematically (up to 11 times) over 6 months, using four commercially available PoC FIV antibody kits (SNAP FIV/FeLV Combo [detects antibodies to p15/p24], Witness FeLV/FIV [gp40], Anigen Rapid FIV/FeLV [p24/gp40] and VetScan FeLV/FIV Rapid [p24]). Results The laboratory-based ELISA showed cats from the original study vaccinated within the previous 0-15 months had detectable levels of antibodies to gp40, despite testing negative with two kits that use gp40 as a capture antigen (Witness and Anigen Rapid kits). The prospective study showed that antibody testing with SNAP Combo and VetScan Rapid was positive in all cats 2 weeks after the second primary FIV vaccination, and remained positive for the duration of the study (12/12 and 10/12 cats positive, respectively). Antibody testing with Witness and Anigen Rapid was also positive in a high proportion of cats 2 weeks after the second primary FIV vaccination (8/12 and 7/12, respectively), but antibody levels declined below the level of detection in

  2. Development of Metabolic Syndrome in Drug-Naive Adolescents After 12 Months of Second-Generation Antipsychotic Treatment

    DEFF Research Database (Denmark)

    Sjo, Christina Power; Stenstrøm, Anne Dorte; Bojesen, Anders Bo

    2017-01-01

    if obesity or metabolic aberration starts in childhood or adolescence. METHODS: Drug-naive adolescents were recruited after contact with an outpatient Psychosis Team. Changes relative to baseline in body mass index (BMI), waist circumference (WC), blood pressure (BP), fasting blood glucose (FBG......), triglycerides (TG), and high-density lipoprotein (HDL) cholesterol were determined through regular follow-ups. RESULTS: The sample included 35 SGA-naive patients aged 7-19 (mean: 15.5) with a diagnosis of psychosis. Over 12 months, the overall rate of MetS changed significantly (from 0% to 20% [p 

  3. Imported Arbovirus Infections in Canada 1974-89

    Directory of Open Access Journals (Sweden)

    Harvey Artsob

    1991-01-01

    Full Text Available From 1974 to 1989, sera from symptomatic patients with histories of recent travel outside Canada were tested for antibodies to several arboviruses, principally of the alphavirus and flavivirus families. Diagnostic seroconversions were documented in 84 individuals from six provinces, including one alphavirus (Chikungunya and 83 flavivirus seroconvertors. Dengue 1 virus was isolated from the blood of one patient. Most flavivirus seroconvertors were likely infected with dengue virus, but infections with tick-borne encephalitis, St Louis encephalitis and Powassan viruses were also recognized. Patients had histories of recent travel to the Caribbean, South America, Asia, Africa, North America (outside Canada, Tahiti, Fiji and Europe. Possible imported infections due to Japanese encephalitis, Ross River, western equine encephalitis and Colorado tick fever viruses were also encountered.

  4. The Effect of Naive Ideas on Students' Reasoning about Electricity and Magnetism

    Science.gov (United States)

    Leppavirta, Johanna

    2012-01-01

    Traditional multiple-choice concept inventories measure students' critical conceptual understanding and are designed to reveal students' naive or alternate ideas. The overall scores, however, give little information about the state of students' knowledge and the consistency of reasoning. This study investigates whether students have consistent…

  5. Viral excretion and antibody titers in children infected with hepatitis A virus from an orphanage in western India.

    Science.gov (United States)

    Hundekar, Supriya; Thorat, Neeta; Gurav, Yogesh; Lole, Kavita

    2015-12-01

    Hepatitis A is endemic in India and mainly causes sporadic infections. However, children in childcare centers, schools and orphanages are vulnerable to common-source outbreaks as they have naive hosts. To investigate hepatitis A outbreak in an orphanage from Pune, India. Monitoring of virus excretion and anti-HAV antibody levels in hepatitis A virus (HAV) infected children. The orphanage housed 93 children of the age 1 month-6.5 years. Analysis of the collected serum (n=78) and stool samples (n=63) revealed 20 children to be either positive for anti-HAV IgM antibodies or excreting HAV, 14 being symptomatic and 6 asymptomatic, while 32 were already anti-HAV IgG positive either due to past HAV exposure (n=7, mean log antibody titers: 2.96) or maternal antibodies (n=25, mean log antibody titers: 1.13). Serum samples, taken 4 weeks apart, did not show any significant difference in the IgM and IgG antibody levels either. However, virus excretion decreased significantly after 15 days in symptomatic children (mean log HAV RNA copies/ml 1.03+0.30), while asymptomatic children continued to excrete higher viral loads, at constant levels (mean log HAV RNA copies/ml 2.33+0.33), for up to 90 days. Though virus excretion continued up to 90 days in all HAV infected children, asymptomatic children excreted higher viral loads for longer period and hence can contribute significantly in person-to-person virus transmission. All children should be vaccinated in such set ups. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Penerapan Data Mining Algoritma Naives Bayes dan PART Untuk Mengetahui Minat Baca Mahasiswa di Perpustakaan STMIK AMIKOM Purwokerto

    Directory of Open Access Journals (Sweden)

    Mohammad Imron

    2017-08-01

    Full Text Available Perpustakaan STMIK AMIKOM Purwokerto didirikan dengan tujuan untuk membantu serta memenuhi kebutuhan sivitas akademik yang ada di Perguruan Tinggi, koleksi buku yang ada sekitar 12,518, dengan judul 6,375 eksemplar. Penelitian ini bertujuan untuk mengetahui minat baca mahasiswa dengan membandingkan tingkat akurasi pada data mining dengan menggunakan algoritma naive bayes dan PART berdasarkan data peminjaman. Pengambilan data dari bulan Januari 2016 sampai bulan Maret 2017 dengan total data 4022. Hasil pengujian yang telah dilakukan terhadap kedua algoritma yaitu algoritma Naive Bayes dan Algoritma PART, maka dapat disimpulkan dari evaluasi dengan confusion matrix didapat hasil nilai akurasi masing-masing algoritma, nilai akurasi dari algoritma naive bayes sebesar 97,01% dan nilai akurasi dari algoritma PART sebesar 97,19%, sehingga algoritma yang terbaik dari pengujian tersebut untuk mengetahui minat baca mahasiswa di Perpustakaan STMIK AMIKOM Purwokerto adalah algoritma PART.

  7. Development of a blocking ELISA for detection of serum neutralizing antibodies against newly emerged duck Tembusu virus.

    Directory of Open Access Journals (Sweden)

    Xuesong Li

    Full Text Available BACKGROUND: Since April 2010, domesticated ducks in China have been suffering from an emerging infectious disease characterized by retarded growth, high fever, loss of appetite, decline in egg production, and death. The causative agent was identified as a duck Tembusu virus (DTMUV, a member of the Ntaya virus (NTAV group within the genus Flavivirus, family Flaviviridae. DTMUV is highly contagious and spreads rapidly in many species of ducks. More than 10 million shelducks have been infected and approximately 1 million died in 2010. The disease remains a constant threat to the duck industry; however, it is not known whether DTMUV can infect humans or other mammalians, despite the fact that the virus has spread widely in southeast China, one of the most densely populated areas in the world. The lack of reliable methods to detect the serum antibodies against DTMUV has limited our ability to conduct epidemiological investigations in various natural hosts and to evaluate the efficiency of vaccines to DTMUV. METHODOLOGY/PRINCIPAL FINDINGS: A neutralizing monoclonal antibody (mAb 1F5 binding specifically to the E protein was developed. Based on the mAb, a blocking enzyme-linked immunosorbent assay (ELISA was developed for the detection of neutralizing antibodies against DTMUV. The average value of percent inhibition (PI of 350 duck serum samples obtained from DTMUV-free farms was 1.0% ± 5.8% (mean ± SD. The selected cut-off PI values for negative and positive sera were 12.6% (mean +2SD and 18.4% (mean +3SD, respectively. When compared with a serum neutralizing antibody test (SNT using chicken embryonated eggs, the rate of coincidence was 70.6% between the blocking ELISA and SNT, based on the titration of 20 duck DTMUV-positive serum samples. CONCLUSIONS/SIGNIFICANCE: The blocking ELISA based on a neutralizing mAb allowed rapid, sensitive, and specific detection of neutralization-related antibodies against DTMUV.

  8. SEROLOGIC EVIDENCE OF WEST NILE VIRUS INFECTION IN BIRDS, TAMAULIPAS STATE, MEXICO

    OpenAIRE

    beaty, barry; FERNANDEZ, ILDEFONSO; contreras, juan francisco; blitvich, bradley; gonzalez, jose ignacio; cavazos, amanda a; loroño, maria alba; gluber, duante j.; Cropp, bruce; Calisher , Charles

    2003-01-01

    Following the introduction of West Nile virus (WNV) into North America in 1999, surveillance for WNV in migratory and resident birds was established in Tamaulipas State, northern Mexico in December 2001. Overall, 796 birds representing 70 species and 10 orders were captured and assayed for antibodies to WNV. Nine birds had flavivirus-specific antibodies by epitope-blocking enzyme-linked immunosorbent assay; four were confirmed to have antibody to WNV by plaque reduction neutralization test. T...

  9. Crystal structure of the Japanese encephalitis virus envelope protein.

    Science.gov (United States)

    Luca, Vincent C; AbiMansour, Jad; Nelson, Christopher A; Fremont, Daved H

    2012-02-01

    Japanese encephalitis virus (JEV) is the leading global cause of viral encephalitis. The JEV envelope protein (E) facilitates cellular attachment and membrane fusion and is the primary target of neutralizing antibodies. We have determined the 2.1-Å resolution crystal structure of the JEV E ectodomain refolded from bacterial inclusion bodies. The E protein possesses the three domains characteristic of flavivirus envelopes and epitope mapping of neutralizing antibodies onto the structure reveals determinants that correspond to the domain I lateral ridge, fusion loop, domain III lateral ridge, and domain I-II hinge. While monomeric in solution, JEV E assembles as an antiparallel dimer in the crystal lattice organized in a highly similar fashion as seen in cryo-electron microscopy models of mature flavivirus virions. The dimer interface, however, is remarkably small and lacks many of the domain II contacts observed in other flavivirus E homodimers. In addition, uniquely conserved histidines within the JEV serocomplex suggest that pH-mediated structural transitions may be aided by lateral interactions outside the dimer interface in the icosahedral virion. Our results suggest that variation in dimer structure and stability may significantly influence the assembly, receptor interaction, and uncoating of virions.

  10. Sleep quality and OPRM1 polymorphisms: a cross-sectional study among opioid-naive individuals

    Directory of Open Access Journals (Sweden)

    Zalina Zahari

    2018-06-01

    Full Text Available ABSTRACT Opioidergic system involves in regulation of sleep and wakefulness. It is possible, therefore, that genetic polymorphisms in OPRM1 influence sleep quality. This study investigated the association of OPRM1 polymorphisms with subjective sleep quality among opioid-naive individuals. This cross-sectional observational study involved 161 opioid-naive males (mean age = 27.74 years; range: 18−63 years. Subjective sleep quality was assessed with the translated and validated Malay version of the Pittsburgh Sleep Quality Index (PSQI. DNA was extracted from whole blood and subjected to polymerase chain reaction (PCR-genotyping for two OPRM1 polymorphisms (118A>G and IVS2+691G>C. Subjects with combined 118A and IVS2+691G alleles (AC haplotype had significantly lower PSQI scores [mean (SD = 4.29 (1.76] compared to those without the haplotype [4.99 (2.50] (p = 0.004. On the other hand, subjects with combined heterozygous genotype (GC/AG diplotype had significantly higher PSQI scores compared to those without the diplotype [6.04 (2.48 vs 4.54 (2.22, p = 0.004]. In opioid-naive individuals, AC haplotype and GC/AG diplotype for the 118A>G and IVS2+691G>C polymorphisms of OPRM1 are associated with better and poorer sleep quality, respectively.

  11. Nicotinic Acid Adenine Dinucleotide Phosphate Plays a Critical Role in Naive and Effector Murine T Cells but Not Natural Regulatory T Cells*

    Science.gov (United States)

    Ali, Ramadan A.; Camick, Christina; Wiles, Katherine; Walseth, Timothy F.; Slama, James T.; Bhattacharya, Sumit; Giovannucci, David R.; Wall, Katherine A.

    2016-01-01

    Nicotinic acid adenine dinucleotide phosphate (NAADP), the most potent Ca2+ mobilizing second messenger discovered to date, has been implicated in Ca2+ signaling in some lymphomas and T cell clones. In contrast, the role of NAADP in Ca2+ signaling or the identity of the Ca2+ stores targeted by NAADP in conventional naive T cells is less clear. In the current study, we demonstrate the importance of NAADP in the generation of Ca2+ signals in murine naive T cells. Combining live-cell imaging methods and a pharmacological approach using the NAADP antagonist Ned-19, we addressed the involvement of NAADP in the generation of Ca2+ signals evoked by TCR stimulation and the role of this signal in downstream physiological end points such as proliferation, cytokine production, and other responses to stimulation. We demonstrated that acidic compartments in addition to the endoplasmic reticulum were the Ca2+ stores that were sensitive to NAADP in naive T cells. NAADP was shown to evoke functionally relevant Ca2+ signals in both naive CD4 and naive CD8 T cells. Furthermore, we examined the role of this signal in the activation, proliferation, and secretion of effector cytokines by Th1, Th2, Th17, and CD8 effector T cells. Overall, NAADP exhibited a similar profile in mediating Ca2+ release in effector T cells as in their counterpart naive T cells and seemed to be equally important for the function of these different subsets of effector T cells. This profile was not observed for natural T regulatory cells. PMID:26728458

  12. Interleukin-7 induces HIV replication in primary naive T cells through a nuclear factor of activated T cell (NFAT)-dependent pathway

    International Nuclear Information System (INIS)

    Managlia, Elizabeth Z.; Landay, Alan; Al-Harthi, Lena

    2006-01-01

    Interleukin (IL)-7 plays several roles critical to T cell maturation, survival, and homeostasis. Because of these functions, IL-7 is under investigation as an immune-modulator for therapeutic use in lymphopenic clinical conditions, including HIV. We reported that naive T cells, typically not permissive to HIV, can be productively infected when pre-treated with IL-7. We evaluated the mechanism by which IL-7-mediates this effect. IL-7 potently up-regulated the transcriptional factor NFAT, but had no effect on NFκB. Blocking NFAT activity using a number of reagents, such as Cyclosporin A, FK-506, or the NFAT-specific inhibitor known as VIVIT peptide, all markedly reduced IL-7-mediated induction of HIV replication in naive T cells. Additional neutralization of cytokines present in IL-7-treated cultures and/or those that have NFAT-binding sequences within their promotors indicated that IL-10, IL-4, and most significantly IFNγ, all contribute to IL-7-induction of HIV productive replication in naive T cells. These data clarify the mechanism by which IL-7 can overcome the block to HIV productive infection in naive T cells, despite their quiescent cell status. These findings are relevant to the treatment of HIV disease and understanding HIV pathogenesis in the naive CD4+ T cell compartment, especially in light of the vigorous pursuit of IL-7 as an in vivo immune modulator

  13. Magnetic resonance imaging-guided biopsies may improve diagnosis in biopsy-naive men with suspicion of prostate cancer

    DEFF Research Database (Denmark)

    Winther, Mads Dochedahl; Balslev, Ingegerd; Boesen, Lars

    2017-01-01

    INTRODUCTION: The purpose of this pilot study was to investigate whether a short prostate biparametric magnetic resonance imaging (bp-MRI) protocol provides a valuable diagnostic addition for biopsy guidance in biopsy-naive men with a suspicion of prostate cancer (PCa). METHODS: A total of 62...... biopsy-naive patients referred to a systematic transrectal ultrasound biopsy (TRUS-bx) due to suspicion of PCa were prospectively enrolled. Bp-MRI was performed before biopsy. All lesions were scored according to the modified Prostate Imaging Reporting and Data System (PI-RADS) version 2. All patients...

  14. Potential for Co-Infection of a Mosquito-Specific Flavivirus, Nhumirim Virus, to Block West Nile Virus Transmission in Mosquitoes

    Directory of Open Access Journals (Sweden)

    Silvina Goenaga

    2015-11-01

    Full Text Available Nhumirim virus (NHUV is an insect-specific virus that phylogenetically affiliates with dual-host mosquito-borne flaviviruses. Previous in vitro co-infection experiments demonstrated prior or concurrent infection of Aedes albopictus C6/36 mosquito cells with NHUV resulted in a 10,000-fold reduction in viral production of West Nile virus (WNV. This interference between WNV and NHUV was observed herein in an additional Ae. albopictus mosquito cell line, C7-10. A WNV 2K peptide (V9M mutant capable of superinfection with a pre-established WNV infection demonstrated a comparable level of interference from NHUV as the parental WNV strain in C6/36 and C7-10 cells. Culex quinquefasciatus and Culex pipiens mosquitoes intrathoracically inoculated with NHUVandWNV, or solely withWNVas a control, were allowed to extrinsically incubate the viruses up to nine and 14 days, respectively, and transmissibility and replication of WNV was determined. The proportion of Cx. quinquefasciatus mosquitoes capable of transmitting WNV was significantly lower for the WNV/NHUV group than the WNV control at seven and nine days post inoculation (dpi, while no differences were observed in the Cx. pipiens inoculation group. By dpi nine, a 40% reduction in transmissibility in mosquitoes from the dual inoculation group was observed compared to the WNV-only control. These data indicate the potential that infection of some Culex spp. vectors with NHUV could serve as a barrier for efficient transmissibility of flaviviruses associated with human disease.

  15. Personality matters: individual variation in reactions of naive bird predators to aposematic prey

    NARCIS (Netherlands)

    Exnerová, A.; Hotova Svadova, K.; Fucikova, E.; Drent, P.; Stys, P.

    2010-01-01

    Variation in reactions to aposematic prey is common among conspecific individuals of bird predators. It may result from different individual experience but it also exists among naive birds. This variation may possibly be explained by the effect of personality—a complex of correlated, heritable

  16. Using Unsupervised Learning to Improve the Naive Bayes Classifier for Wireless Sensor Networks

    NARCIS (Netherlands)

    Zwartjes, G.J.; Havinga, Paul J.M.; Smit, Gerardus Johannes Maria; Hurink, Johann L.

    2012-01-01

    Online processing is essential for many sensor network applications. Sensor nodes can sample far more data than what can practically be transmitted using state of the art sensor network radios. Online processing, however, is complicated due to limited resources of individual nodes. The naive Bayes

  17. Nicotinic Acid Adenine Dinucleotide Phosphate Plays a Critical Role in Naive and Effector Murine T Cells but Not Natural Regulatory T Cells.

    Science.gov (United States)

    Ali, Ramadan A; Camick, Christina; Wiles, Katherine; Walseth, Timothy F; Slama, James T; Bhattacharya, Sumit; Giovannucci, David R; Wall, Katherine A

    2016-02-26

    Nicotinic acid adenine dinucleotide phosphate (NAADP), the most potent Ca(2+) mobilizing second messenger discovered to date, has been implicated in Ca(2+) signaling in some lymphomas and T cell clones. In contrast, the role of NAADP in Ca(2+) signaling or the identity of the Ca(2+) stores targeted by NAADP in conventional naive T cells is less clear. In the current study, we demonstrate the importance of NAADP in the generation of Ca(2+) signals in murine naive T cells. Combining live-cell imaging methods and a pharmacological approach using the NAADP antagonist Ned-19, we addressed the involvement of NAADP in the generation of Ca(2+) signals evoked by TCR stimulation and the role of this signal in downstream physiological end points such as proliferation, cytokine production, and other responses to stimulation. We demonstrated that acidic compartments in addition to the endoplasmic reticulum were the Ca(2+) stores that were sensitive to NAADP in naive T cells. NAADP was shown to evoke functionally relevant Ca(2+) signals in both naive CD4 and naive CD8 T cells. Furthermore, we examined the role of this signal in the activation, proliferation, and secretion of effector cytokines by Th1, Th2, Th17, and CD8 effector T cells. Overall, NAADP exhibited a similar profile in mediating Ca(2+) release in effector T cells as in their counterpart naive T cells and seemed to be equally important for the function of these different subsets of effector T cells. This profile was not observed for natural T regulatory cells. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  18. West Nile virus equine serosurvey in the Czech and Slovak Republics

    Czech Academy of Sciences Publication Activity Database

    Hubálek, Zdeněk; Ludvíková, E.; Jahn, P.; Treml, F.; Rudolf, Ivo; Svobodová, Petra; Šikutová, Silvie; Betášová, Lenka; Bíreš, J.; Mojžíš, M.; Tinák, M.; Boldižár, M.; Citsoňová, G.; Staššíková, Z.

    2013-01-01

    Roč. 13, č. 10 (2013), s. 733-738 ISSN 1530-3667 Institutional support: RVO:68081766 Keywords : Flavivirus * Mosquito-borne virus * West Nile virus * Neutralizing antibodies * Horses Subject RIV: EE - Microbiology, Virology Impact factor: 2.531, year: 2013

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

    Directory of Open Access Journals (Sweden)

    Encheng Sun

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

  20. Nucleotide and deduced amino acid sequence of the envelope gene of the Vasilchenko strain of TBE virus; comparison with other flaviviruses.

    Science.gov (United States)

    Gritsun, T S; Frolova, T V; Pogodina, V V; Lashkevich, V A; Venugopal, K; Gould, E A

    1993-02-01

    A strain of tick-borne encephalitis virus known as Vasilchenko (Vs) exhibits relatively low virulence characteristics in monkeys, Syrian hamsters and humans. The gene encoding the envelope glycoprotein of this virus was cloned and sequenced. Alignment of the sequence with those of other known tick-borne flaviviruses and identification of the recognised amino acid genetic marker EHLPTA confirmed its identity as a member of the TBE complex. However, Vs virus was distinguishable from eastern and western tick-borne serotypes by the presence of the sequence AQQ at amino acid positions 232-234 and also by the presence of other specific amino acid substitutions which may be genetic markers for these viruses and could determine their pathogenetic characteristics. When compared with other tick-borne flaviviruses, Vs virus had 12 unique amino acid substitutions including an additional potential glycosylation site at position (315-317). The Vs virus strain shared closest nucleotide and amino acid homology (84.5% and 95.5% respectively) with western and far eastern strains of tick-borne encephalitis virus. Comparison with the far eastern serotype of tick-borne encephalitis virus, by cross-immunoelectrophoresis of Vs virions and PAGE analysis of the extracted virion proteins, revealed differences in surface charge and virus stability that may account for the different virulence characteristics of Vs virus. These results support and enlarge upon previous data obtained from molecular and serological analysis.

  1. A Combined Omics Approach to Generate the Surface Atlas of Human Naive CD4+ T Cells during Early T-Cell Receptor Activation.

    Science.gov (United States)

    Graessel, Anke; Hauck, Stefanie M; von Toerne, Christine; Kloppmann, Edda; Goldberg, Tatyana; Koppensteiner, Herwig; Schindler, Michael; Knapp, Bettina; Krause, Linda; Dietz, Katharina; Schmidt-Weber, Carsten B; Suttner, Kathrin

    2015-08-01

    Naive CD4(+) T cells are the common precursors of multiple effector and memory T-cell subsets and possess a high plasticity in terms of differentiation potential. This stem-cell-like character is important for cell therapies aiming at regeneration of specific immunity. Cell surface proteins are crucial for recognition and response to signals mediated by other cells or environmental changes. Knowledge of cell surface proteins of human naive CD4(+) T cells and their changes during the early phase of T-cell activation is urgently needed for a guided differentiation of naive T cells and may support the selection of pluripotent cells for cell therapy. Periodate oxidation and aniline-catalyzed oxime ligation technology was applied with subsequent quantitative liquid chromatography-tandem MS to generate a data set describing the surface proteome of primary human naive CD4(+) T cells and to monitor dynamic changes during the early phase of activation. This led to the identification of 173 N-glycosylated surface proteins. To independently confirm the proteomic data set and to analyze the cell surface by an alternative technique a systematic phenotypic expression analysis of surface antigens via flow cytometry was performed. This screening expanded the previous data set, resulting in 229 surface proteins, which were expressed on naive unstimulated and activated CD4(+) T cells. Furthermore, we generated a surface expression atlas based on transcriptome data, experimental annotation, and predicted subcellular localization, and correlated the proteomics result with this transcriptional data set. This extensive surface atlas provides an overall naive CD4(+) T cell surface resource and will enable future studies aiming at a deeper understanding of mechanisms of T-cell biology allowing the identification of novel immune targets usable for the development of therapeutic treatments. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. A Chinese text classification system based on Naive Bayes algorithm

    Directory of Open Access Journals (Sweden)

    Cui Wei

    2016-01-01

    Full Text Available In this paper, aiming at the characteristics of Chinese text classification, using the ICTCLAS(Chinese lexical analysis system of Chinese academy of sciences for document segmentation, and for data cleaning and filtering the Stop words, using the information gain and document frequency feature selection algorithm to document feature selection. Based on this, based on the Naive Bayesian algorithm implemented text classifier , and use Chinese corpus of Fudan University has carried on the experiment and analysis on the system.

  3. DeNASA: Destination-Naive AS-Awareness in Anonymous Communications

    Directory of Open Access Journals (Sweden)

    Barton Armon

    2016-10-01

    Full Text Available Prior approaches to AS-aware path selection in Tor do not consider node bandwidth or the other characteristics that Tor uses to ensure load balancing and quality of service. Further, since the AS path from the client’s exit to her destination can only be inferred once the destination is known, the prior approaches may have problems constructing circuits in advance, which is important for Tor performance. In this paper, we propose and evaluate DeNASA, a new approach to AS-aware path selection that is destination-naive, in that it does not need to know the client’s destination to pick paths, and that takes advantage of Tor’s circuit selection algorithm. To this end, we first identify the most probable ASes to be traversed by Tor streams. We call this set of ASes the Suspect AS list and find that it consists of eight highest ranking Tier 1 ASes. Then, we test the accuracy of Qiu and Gao AS-level path inference on identifying the presence of these ASes in the path, and we show that inference accuracy is 90%. We develop an AS-aware algorithm called DeNASA that uses Qiu and Gao inference to avoid Suspect ASes. DeNASA reduces Tor stream vulnerability by 74%. We also show that DeNASA has performance similar to Tor. Due to the destination-naive property, time to first byte (TTFB is close to Tor’s, and due to leveraging Tor’s bandwidth-weighted relay selection, time to last byte (TTLB is also similar to Tor’s.

  4. Efficacy of tofacitinib monotherapy in methotrexate-naive patients with early or established rheumatoid arthritis

    NARCIS (Netherlands)

    Fleischmann, Roy M.; Huizinga, Tom W. J.; Kavanaugh, Arthur F.; Wilkinson, Bethanie; Kwok, Kenneth; DeMasi, Ryan; van Vollenhoven, Ronald F.

    2016-01-01

    Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA). Tofacitinib monotherapy was previously shown to inhibit structural damage, reduce clinical signs and symptoms of RA, and improve physical functioning over 24 months in methotrexate (MTX)-naive adult

  5. Prevalence of Dyslipidemia Among Antiretroviral-Naive HIV-Infected Individuals in China

    Science.gov (United States)

    Shen, Yinzhong; Wang, Jiangrong; Wang, Zhenyan; Qi, Tangkai; Song, Wei; Tang, Yang; Liu, Li; Zhang, Renfang; Lu, Hongzhou

    2015-01-01

    Abstract Little is known about the epidemiological features of dyslipidemia among antiretroviral-naive HIV-infected individuals in China. We used a cross-sectional study design to estimate the prevalence of dyslipidemia in this population, and to identify risk factors associated with the presence of dyslipidemia. One thousand five hundred and eighteen antiretroviral-naive HIV-infected individuals and 347 HIV-negative subjects in China were enrolled during 2009 to 2010. Demographics and medical histories were recorded. After an overnight fast, serum samples were collected to measure lipid levels. Factors associated with the presence of dyslipidemia were analyzed by logistic regression. Mean total cholesterol (TC), low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL) levels were lower in HIV-positive than HIV-negative subjects, but mean triglyceride (TG) was higher in HIV-positive subjects. The overall prevalence of dyslipidemia in HIV-positive and HIV-negative groups did not differ (75.6% vs. 73.7%, P = 0.580). However, the prevalence of high TC (8.4% vs. 28.2%, P dyslipidemia characterized by high TG and low HDL, which was associated with lower CD4 counts. These data support the assessment of lipid profiles before and after initiation of antiretroviral therapy regardless of age. PMID:26632908

  6. Anterior Cingulate Volumetric Alterations in Treatment-Naive Adults with ADHD: A Pilot Study

    Science.gov (United States)

    Makris, Nikos; Seidman, Larry J.; Valera, Eve M.; Biederman, Joseph; Monuteaux, Michael C.; Kennedy, David N.; Caviness, Verne S., Jr.; Bush, George; Crum, Katherine; Brown, Ariel B.; Faraone, Stephen V.

    2010-01-01

    Objective: We sought to examine preliminary results of brain alterations in anterior cingulate cortex (ACC) in treatment-naive adults with ADHD. The ACC is a central brain node for the integration of cognitive control and allocation of attention, affect and drive. Thus its anatomical alteration may give rise to impulsivity, hyperactivity and…

  7. The mysterious Zika virus: Adding to the tropical flavivirus mayhem

    Directory of Open Access Journals (Sweden)

    B Mishra

    2016-01-01

    Full Text Available Until now, known as the demure cousin of dengue virus (DENV inhabiting Africa, Zika virus (ZIKV has reinvented itself to cause explosive epidemics captivating the Western hemisphere. The outbreak causing potential for ZIKV was realized when it made its way from Africa to Yap Island Micronesia in 2007, and in French Polynesia in 2013. From there, it moved on to Brazil in 2015. Now ZIKV has infected people in more than 33 countries in Central and South America and the Caribbean. Moreover the epidemiological and subsequent virological association with microcephaly cases in Brazil has prompted the World Health Organization to declare a public health emergency of International Concern. ZIKV shares not only its vector Aedes aegypti with dengue and chikungunya but also the geographic distribution and clinical features, which makes the laboratory confirmation mandatory for definitive diagnosis. The serological cross-reactivity with other Flavivirus, particularly with DENV makes laboratory confirmation challenging and will place additional burden on health systems to establish molecular diagnostic facilities. The evidence of additional nonvector modes of transmission, such as perinatal, sexual as well as transfusion has made preventative strategies more difficult. As ZIKV disease continues to mystify us with several unanswered questions, it calls for coordinated effort of global scientific community to address the ever growing arboviral threat to mankind.

  8. Dengue-yellow fever sera cross-reactivity; challenges for diagnosis

    OpenAIRE

    Houghton-Triviño, Natalia; Montaña, Diana; Castellanos, Jaime

    2008-01-01

    Objective The Flavivirus genera share epitopes inducing cross-reactive antibodies leading to great difficulty in differentially diagnosing flaviviral infections. This work was aimed at evaluating the complexity of dengue and yellow fever serological differential diagnosis. Material and methods Dengue antibody capture ELISA and a yellow fever neutralisation test were carried out on 13 serum samples obtained from yellow fever patients, 20 acute serum samples from dengue patients and 19 voluntan...

  9. The F4/AS01B HIV-1 Vaccine Candidate Is Safe and Immunogenic, But Does Not Show Viral Efficacy in Antiretroviral Therapy-Naive, HIV-1-Infected Adults

    Science.gov (United States)

    Dinges, Warren; Girard, Pierre-Marie; Podzamczer, Daniel; Brockmeyer, Norbert H.; García, Felipe.; Harrer, Thomas; Lelievre, Jean-Daniel; Frank, Ian; Colin De Verdière, Nathalie; Yeni, Guy-Patrick; Ortega Gonzalez, Enrique; Rubio, Rafael; Clotet Sala, Bonaventura; DeJesus, Edwin; Pérez-Elias, Maria Jesus; Launay, Odile; Pialoux, Gilles; Slim, Jihad; Weiss, Laurence; Bouchaud, Olivier; Felizarta, Franco; Meurer, Anja; Raffi, François; Esser, Stefan; Katlama, Christine; Koletar, Susan L.; Mounzer, Karam; Swindells, Susan; Baxter, John D.; Schneider, Stefan; Chas, Julie; Molina, Jean-Michel; Koutsoukos, Marguerite; Collard, Alix; Bourguignon, Patricia; Roman, François

    2016-01-01

    Abstract The impact of the investigational human immunodeficiency virus type 1 (HIV-1) F4/AS01B vaccine on HIV-1 viral load (VL) was evaluated in antiretroviral therapy (ART)-naive HIV-1 infected adults. This phase IIb, observer-blind study (NCT01218113), included ART-naive HIV-1 infected adults aged 18 to 55 years. Participants were randomized to receive 2 (F4/AS01B_2 group, N = 64) or 3 (F4/AS01B_3 group, N = 62) doses of F4/AS01B or placebo (control group, N = 64) at weeks 0, 4, and 28. Efficacy (HIV-1 VL, CD4+ T-cell count, ART initiation, and HIV-related clinical events), safety, and immunogenicity (antibody and T-cell responses) were evaluated during 48 weeks. At week 48, based on a mixed model, no statistically significant difference in HIV-1 VL change from baseline was demonstrated between F4/AS01B_2 and control group (0.073 log10 copies/mL [97.5% confidence interval (CI): −0.088; 0.235]), or F4/AS01B_3 and control group (−0.096 log10 copies/mL [97.5% CI: −0.257; 0.065]). No differences between groups were observed in HIV-1 VL change, CD4+ T-cell count, ART initiation, or HIV-related clinical events at intermediate timepoints. Among F4/AS01B recipients, the most frequent solicited symptoms were pain at injection site (252/300 doses), fatigue (137/300 doses), myalgia (105/300 doses), and headache (90/300 doses). Twelve serious adverse events were reported in 6 participants; 1 was considered vaccine-related (F4/AS01B_2 group: angioedema). F4/AS01B induced polyfunctional F4-specific CD4+ T-cells, but had no significant impact on F4-specific CD8+ T-cell and anti-F4 antibody levels. F4/AS01B had a clinically acceptable safety profile, induced F4-specific CD4+ T-cell responses, but did not reduce HIV-1 VL, impact CD4+ T-cells count, delay ART initiation, or prevent HIV-1 related clinical events. PMID:26871794

  10. 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

  11. KLF4 Nuclear Export Requires ERK Activation and Initiates Exit from Naive Pluripotency.

    Science.gov (United States)

    Dhaliwal, Navroop K; Miri, Kamelia; Davidson, Scott; Tamim El Jarkass, Hala; Mitchell, Jennifer A

    2018-04-10

    Cooperative action of a transcription factor complex containing OCT4, SOX2, NANOG, and KLF4 maintains the naive pluripotent state; however, less is known about the mechanisms that disrupt this complex, initiating exit from pluripotency. We show that, as embryonic stem cells (ESCs) exit pluripotency, KLF4 protein is exported from the nucleus causing rapid decline in Nanog and Klf4 transcription; as a result, KLF4 is the first pluripotency transcription factor removed from transcription-associated complexes during differentiation. KLF4 nuclear export requires ERK activation, and phosphorylation of KLF4 by ERK initiates interaction of KLF4 with nuclear export factor XPO1, leading to KLF4 export. Mutation of the ERK phosphorylation site in KLF4 (S132) blocks KLF4 nuclear export, the decline in Nanog, Klf4, and Sox2 mRNA, and differentiation. These findings demonstrate that relocalization of KLF4 to the cytoplasm is a critical first step in exit from the naive pluripotent state and initiation of ESC differentiation. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  12. First international collaborative study to evaluate rabies antibody detection method for use in monitoring the effectiveness of oral vaccination programmes in fox and raccoon dog in Europe

    DEFF Research Database (Denmark)

    Wasniewski, M; Almeida, I; Baur, A

    2016-01-01

    The most effective and sustainable method to control and eliminate rabies in wildlife is the oral rabies vaccination (ORV) of target species, namely foxes and raccoon dogs in Europe. According to WHO and OIE, the effectiveness of oral vaccination campaigns should be regularly assessed via disease...... surveillance and ORV antibody monitoring. Rabies antibodies are generally screened for in field animal cadavers, whose body fluids are often of poor quality. Therefore, the use of alternative methods such as the enzyme-linked immunosorbent assay (ELISA) has been proposed to improve reliability of serological...... results obtained on wildlife samples. We undertook an international collaborative study to determine if the commercial BioPro ELISA Rabies Ab kit is a reliable and reproducible tool for rabies serological testing. Our results reveal that the overall specificity evaluated on naive samples reached 96...

  13. Naive Bayes as opinion classifier to evaluate students satisfaction based on student sentiment in Twitter Social Media

    Science.gov (United States)

    Candra Permana, Fahmi; Rosmansyah, Yusep; Setiawan Abdullah, Atje

    2017-10-01

    Students activity on social media can provide implicit knowledge and new perspectives for an educational system. Sentiment analysis is a part of text mining that can help to analyze and classify the opinion data. This research uses text mining and naive Bayes method as opinion classifier, to be used as an alternative methods in the process of evaluating studentss satisfaction for educational institution. Based on test results, this system can determine the opinion classification in Bahasa Indonesia using naive Bayes as opinion classifier with accuracy level of 84% correct, and the comparison between the existing system and the proposed system to evaluate students satisfaction in learning process, there is only a difference of 16.49%.

  14. Neutralization of tier-2 viruses and epitope profiling of plasma antibodies from human immunodeficiency virus type 1 infected donors from India.

    Directory of Open Access Journals (Sweden)

    Raiees Andrabi

    Full Text Available Broadly cross neutralizing antibodies (NAbs are generated in a group of HIV-1 infected individuals during the natural infection, but little is known about their prevalence in patients infected with viral subtypes from different geographical regions. We tested here the neutralizing efficiency of plasma antibodies from 80 HIV-1 infected antiretroviral drug naive patients against a panel of subtype-B and C tier 2 viruses. We detected cross-neutralizing antibodies in approximately 19-27% of the plasma, however the subtype-C specific neutralization efficiency predominated (p = 0.004. The neutralizing activity was shown to be exclusively mediated by the immunoglobulin G (IgG fraction in the representative plasma samples. Epitope mapping of three, the most cross-neutralizing plasma (CNP AIIMS206, AIIMS239 and AIIMS249 with consensus-C overlapping envelope peptides revealed ten different binding specificities with only V3 and IDR being common. The V3 and IDR were highly antigenic regions but no correlation between their reciprocal Max50 binding titers and neutralization was observed. In addition, the neutralizing activity of CNP was not substantially reduced by V3 and gp41 peptides except a modest contribution of MPER peptide. The MPER was rarely recognized by plasma antibodies though antibody depletion and competition experiments demonstrated MPER dependent neutralization in two out of three CNP. Interestingly, the binding specificity of one of the CNP (AIIMS206 overlapped with broadly neutralizing mAb 2F5 epitope. Overall, the data suggest that, despite the low immunogenicity of HIV-1 MPER, the antibodies directed to this region may serve as crucial reagents for HIV-1 vaccine design.

  15. Decreased frontal serotonin2A receptor binding in antipsychotic-naive patients with first-episode schizophrenia

    DEFF Research Database (Denmark)

    Rasmussen, Hans; Erritzoe, David; Andersen, Rune

    2010-01-01

    , in vivo studies of serotonin(2A) binding report conflicting results, presumably because sample sizes have been small or because schizophrenic patients who were not antipsychotic-naive were included. Furthermore, the relationships between serotonin(2A) binding, psychopathology, and central neurocognitive...

  16. Providing probability distributions for the causal pathogen of clinical mastitis using naive Bayesian networks

    NARCIS (Netherlands)

    Steeneveld, W.; Gaag, van der L.C.; Barkema, H.W.; Hogeveen, H.

    2009-01-01

    Clinical mastitis (CM) can be caused by a wide variety of pathogens and farmers must start treatment before the actual causal pathogen is known. By providing a probability distribution for the causal pathogen, naive Bayesian networks (NBN) can serve as a management tool for farmers to decide which

  17. In Vitro Measles Virus Infection of Human Lymphocyte Subsets Demonstrates High Susceptibility and Permissiveness of both Naive and Memory B Cells.

    Science.gov (United States)

    Laksono, Brigitta M; Grosserichter-Wagener, Christina; de Vries, Rory D; Langeveld, Simone A G; Brem, Maarten D; van Dongen, Jacques J M; Katsikis, Peter D; Koopmans, Marion P G; van Zelm, Menno C; de Swart, Rik L

    2018-04-15

    Measles is characterized by a transient immune suppression, leading to an increased risk of opportunistic infections. Measles virus (MV) infection of immune cells is mediated by the cellular receptor CD150, expressed by subsets of lymphocytes, dendritic cells, macrophages, and thymocytes. Previous studies showed that human and nonhuman primate memory T cells express higher levels of CD150 than naive cells and are more susceptible to MV infection. However, limited information is available about the CD150 expression and relative susceptibility to MV infection of B-cell subsets. In this study, we assessed the susceptibility and permissiveness of naive and memory T- and B-cell subsets from human peripheral blood or tonsils to in vitro MV infection. Our study demonstrates that naive and memory B cells express CD150, but at lower frequencies than memory T cells. Nevertheless, both naive and memory B cells proved to be highly permissive to MV infection. Furthermore, we assessed the susceptibility and permissiveness of various functionally distinct T and B cells, such as helper T (T H ) cell subsets and IgG- and IgA-positive memory B cells, in peripheral blood and tonsils. We demonstrated that T H 1T H 17 cells and plasma and germinal center B cells were the subsets most susceptible and permissive to MV infection. Our study suggests that both naive and memory B cells, along with several other antigen-experienced lymphocytes, are important target cells of MV infection. Depletion of these cells potentially contributes to the pathogenesis of measles immune suppression. IMPORTANCE Measles is associated with immune suppression and is often complicated by bacterial pneumonia, otitis media, or gastroenteritis. Measles virus infects antigen-presenting cells and T and B cells, and depletion of these cells may contribute to lymphopenia and immune suppression. Measles has been associated with follicular exhaustion in lymphoid tissues in humans and nonhuman primates, emphasizing the

  18. Maraviroc: perspectives for use in antiretroviral-naive HIV-1-infected patients.

    Science.gov (United States)

    Vandekerckhove, Linos; Verhofstede, Chris; Vogelaers, Dirk

    2009-06-01

    Maraviroc (Pfizer's UK-427857, Selzentry or Celsentri outside the USA) is the first agent in the new class of oral HIV-1 entry inhibitors to acquire approval by the US Food and Drug Administration and the European Medicine Agency. Considering the mechanism of action, it is expected that this drug will be effective only in a subpopulation of HIV-1-infected people, namely those harbouring the R5 virus. The favourable toxicity profile of the drug has been demonstrated in Phase III clinical trials in treatment-naive (MERIT) and treatment-experienced (MOTIVATE) patients. In the latter population, maraviroc showed a superior antiviral efficacy and immunological activity compared with optimized backbone therapy + placebo. However, in MERIT, a prospective double-blind, randomized trial in treatment-naive patients, maraviroc + zidovudine/lamivudine failed to prove non-inferiority to efavirenz + zidovudine/lamivudine as standard of care regimen in the 48 week intention-to-treat analysis. Using an assay with higher sensitivity for minority CXCR4-using (X4) HIV variants (the enhanced Trofile assay-Monogram), non-inferiority was reached for the maraviroc- versus efavirenz-based combination. These data indicate the important impact of the sensitivity of tropism testing on treatment outcome of maraviroc-containing regimens. This paper discusses both the prospective and retrospective analyses of the MERIT data and highlights the impact of these results on daily practice in HIV care.

  19. Major clinical outcomes in antiretroviral therapy (ART)-naive participants and in those not receiving ART at baseline in the SMART study

    DEFF Research Database (Denmark)

    Lundgren, Jens; Emery, Sean; Neuhaus, Jacqueline A

    2008-01-01

    BACKGROUND: The SMART study randomized 5,472 human immunodeficiency virus (HIV)-infected patients with CD4+ cell counts >350 cells/microL to intermittent antiretroviral therapy (ART; the drug conservation [DC] group) versus continuous ART (the viral suppression [VS] group). In the DC group......, participants started ART when the CD4+ cell count was ART at entry inform the early use of ART. METHODS: Patients who were either ART naive (n=249) or who had not been receiving ART for >or= 6 months (n=228) were analyzed. The following......). RESULTS: A total of 477 participants (228 in the DC group and 249 in the VS group) were followed (mean, 18 months). For outcome (iv), 21 and 6 events occurred in the DC (7 in ART-naive participants and 14 in those who had not received ART for >or= 6 months) and VS (2 in ART-naive participants and 4...

  20. Next Generation Antibody Therapeutics Using Bispecific Antibody Technology.

    Science.gov (United States)

    Igawa, Tomoyuki

    2017-01-01

    Nearly fifty monoclonal antibodies have been approved to date, and the market for monoclonal antibodies is expected to continue to grow. Since global competition in the field of antibody therapeutics is intense, we need to establish novel antibody engineering technologies to provide true benefit for patients, with differentiated product values. Bispecific antibodies are among the next generation of antibody therapeutics that can bind to two different target antigens by the two arms of immunoglobulin G (IgG) molecule, and are thus believed to be applicable to various therapeutic needs. Until recently, large scale manufacturing of human IgG bispecific antibody was impossible. We have established a technology, named asymmetric re-engineering technology (ART)-Ig, to enable large scale manufacturing of bispecific antibodies. Three examples of next generation antibody therapeutics using ART-Ig technology are described. Recent updates on bispecific antibodies against factor IXa and factor X for the treatment of hemophilia A, bispecific antibodies against a tumor specific antigen and T cell surface marker CD3 for cancer immunotherapy, and bispecific antibodies against two different epitopes of soluble antigen with pH-dependent binding property for the elimination of soluble antigen from plasma are also described.

  1. Radioimmunoassay with heterologous antibody (hetero-antibody RIA)

    International Nuclear Information System (INIS)

    Iwasawa, Atsushi; Hayashi, Hiroaki; Itoh, Zen; Wakabayashi, Katsumi

    1991-01-01

    To develop a homologous radioimmunoassay (RIA) for a hormone of a small or rare animal often meets difficulty in collecting a large amount of purified antigen required for antibody production. On the other hand, to employ a heterologous RIA to estimate the hormone often gives poor sensitivity. To overcome this difficulty, a 'hetero-antibody' RIA was studied. In a hetero-antibody RIA system, a purified preparation of a hormone is used for radioiodination and standardization and a heterologous antibody to the hormone is used for the first antibody. Canine motilin and rat LH were selected as examples, and anti-porcine motilin and anti-hCG, anti-hCGβ or anti-ovine LHβ was used as the heterologous antibody. The sensitivities of the hetero-antibody RIAs were much higher than those of heterologous RIAs in any case, showing that these hetero-antibody RIA systems were suitable for practical use. To clarify the principle of hetero-antibody RIA, antiserum to porcine motilin was fractionated on an affinity column where canine motilin was immobilized. The fraction bound had greater constants of affinity with both porcine and canine motilins than the rest of the antibody fractions. This fraction also reacted with a synthetic peptide corresponding to the C-terminal sequence common to porcine and canine motilins in a competitive binding test with labeled canine motilin. These results suggest that an antibody population having high affinity and cross-reactivity is present in polyclonal antiserum and indicate that the population can be used in hetero-antibody RIA at an appropriate concentration. (author)

  2. Antibodies and Selection of Monoclonal Antibodies.

    Science.gov (United States)

    Hanack, Katja; Messerschmidt, Katrin; Listek, Martin

    Monoclonal antibodies are universal binding molecules with a high specificity for their target and are indispensable tools in research, diagnostics and therapy. The biotechnological generation of monoclonal antibodies was enabled by the hybridoma technology published in 1975 by Köhler and Milstein. Today monoclonal antibodies are used in a variety of applications as flow cytometry, magnetic cell sorting, immunoassays or therapeutic approaches. First step of the generation process is the immunization of the organism with appropriate antigen. After a positive immune response the spleen cells are isolated and fused with myeloma cells in order to generate stable, long-living antibody-producing cell lines - hybridoma cells. In the subsequent identification step the culture supernatants of all hybridoma cells are screened weekly for the production of the antibody of interest. Hybridoma cells producing the antibody of interest are cloned by limited dilution till a monoclonal hybridoma is found. This is a very time-consuming and laborious process and therefore different selection strategies were developed since 1975 in order to facilitate the generation of monoclonal antibodies. Apart from common automation of pipetting processes and ELISA testing there are some promising approaches to select the right monoclonal antibody very early in the process to reduce time and effort of the generation. In this chapter different selection strategies for antibody-producing hybridoma cells are presented and analysed regarding to their benefits compared to conventional limited dilution technology.

  3. Intravitreal bevacizumab (Avastin) for neovascular age-related macular degeneration in treatment-naive patients

    DEFF Research Database (Denmark)

    Pedersen, Karen Bjerg; Sjølie, Anne Katrin; Møller, Flemming

    2008-01-01

    Abstract. Purpose: To report the effects of intravitreal bevacizumab (Avastin((R))) in treatment-naive patients with exudative age-related macular degeneration (ARMD) assessed by visual acuity (VA), optical coherence tomography (OCT) and contrast sensitivity. Methods: A prospective, uncontrolled...... was not statistically significant. Mean macular thickness decreased significantly from baseline to all follow-up examinations (P Macular thickness improved significantly at all time...

  4. Virological failure and HIV-1 drug resistance mutations among naive and antiretroviral pre-treated patients entering the ESTHER program of Calmette Hospital in Cambodia.

    Directory of Open Access Journals (Sweden)

    Hubert Barennes

    Full Text Available INTRODUCTION: In resource limited settings, patients entering an antiretroviral therapy (ART program comprise ART naive and ART pre-treated patients who may show differential virological outcomes. METHODS: This retrospective study, conducted in 2010-2012 in the HIV clinic of Calmette Hospital located in Phnom Penh (Cambodia assessed virological failure (VF rates and patterns of drug resistance of naive and pre-treated patients. Naive and ART pre-treated patients were included when a Viral Load (VL was performed during the first year of ART for naive subjects or at the first consultation for pre-treated individuals. Patients showing Virological failure (VF (>1,000 copies/ml underwent HIV DR genotyping testing. Interpretation of drug resistance mutations was done according to 2013 version 23 ANRS algorithms. RESULTS: On a total of 209 patients, 164 (78.4% were naive and 45 (21.5% were ART pre-treated. Their median initial CD4 counts were 74 cells/mm3 (IQR: 30-194 and 279 cells/mm3 (IQR: 103-455 (p<0.001, respectively. Twenty seven patients (12.9% exhibited VF (95% CI: 8.6-18.2%, including 10 naive (10/164, 6.0% and 17 pre-treated (17/45, 37.8% patients (p<0.001. Among these viremic patients, twenty-two (81.4% were sequenced in reverse transcriptase and protease coding regions. Overall, 19 (86.3% harbored ≥1 drug resistance mutations (DRMs whereas 3 (all belonging to pre-treated patients harbored wild-types viruses. The most frequent DRMs were M184V (86.3%, K103N (45.5% and thymidine analog mutations (TAMs (40.9%. Two (13.3% pre-treated patients harbored viruses that showed a multi-nucleos(tide resistance including Q151M, K65R, E33A/D, E44A/D mutations. CONCLUSION: In Cambodia, VF rates were low for naive patients but the emergence of DRMs to NNRTI and 3TC occurred relatively quickly in this subgroup. In pre-treated patients, VF rates were much higher and TAMs were relatively common. HIV genotypic assays before ART initiation and for ART pre

  5. [Arboviroses in the region of Nosy-Bé, Madagascar. Serologic and entomologic data].

    Science.gov (United States)

    Fontenille, D; Mathiot, C; Rodhain, F; Coulanges, P

    1988-01-01

    Since 1977, the Pasteur Institute of Madagascar has been studying, during six surveys, the arboviruses of Nosy-Be area, in the north-west of Madagascar. 47.2% out of 271 human sera and 11.3% out of 151 sera of Lemurs, tested for antibodies to 16 arboviruses by the haemagglutination inhibition test, are positive. The results show an important prevalence of Flaviviruses. West Nile and Dengue 1 viruses were probably circulating some years before the surveys. Antibodies against Sindbis and Rift Valley Fever viruses, were found only in few subjects. Bunyamwera and California groups of virus are absent. The rate of positive Lemurs is weak, particularly in Lemur macaco macaco. Flaviviruses are the most frequent. 12,262 haematophagous diptera (11,965 Culicidae belonging to 40 species) were caught. Aedes aegypti and Aedes albopictus are both present. Arbovirus isolation attempts from 394 mosquito pools failed; only Mengo virus was isolated from four pools of Eretmapodites quinquevittatus and one pool of Aedes (Skusea) sp.

  6. [Arbovirus infections on the island of Nosy-Be; serologic and entomologic findings].

    Science.gov (United States)

    Fontenille, D; Mathiot, C; Rodhain, F; Coulanges, P

    1988-01-01

    Since 1977, the Pasteur Institute of madagascar has been studying, during six surveys, the arboviruses of Nosy-Be area, in the north-west of Madagascar. 47.2 p. 100 out of 271 human sera and 11.3 p. 100 out of 150 animal sera (mostly from Lemurs), tested for antibodies to 16 arboviruses by the haemagglutination inhibition test, are positive. The results show an important prevalence of Flaviviruses. West-Nile and Dengue 1 viruses were probably circulating some years before the surveys. Antibodies against Sindbis and Rift Valley Fever viruses, were found only in few subjects. Bunyamwera and Tahyna viruses are absent. The rate of positive Lemurs is weak, particularly in Lemur macaco species. Flaviviruses are the most frequent. 12262 haematophagous diptera (11965 Culicidae belonging to 40 species) were caught . Aedes aegypti and Aedes albopictus are both present. Arbovirus isolation attempts from 394 mosquito pools failed; only Mengo virus was isolated from four pools of Erethmapodites quinquevittatus and one pool of Aedes (Skusea) sp.

  7. Antiviral Properties of the Natural Polyphenols Delphinidin and Epigallocatechin Gallate against the Flaviviruses West Nile Virus, Zika Virus, and Dengue Virus

    Directory of Open Access Journals (Sweden)

    Ángela Vázquez-Calvo

    2017-07-01

    Full Text Available The Flavivirus genus contains important pathogens, such as West Nile virus (WNV, Zika virus (ZIKV, and Dengue virus (DENV, which are enveloped plus-strand RNA viruses transmitted by mosquitoes and constitute a worrisome threat to global human and animal health. Currently no licensed drugs against them are available, being, thus, still necessary the search for effective antiviral molecules. In this line, a novel antiviral approach (economical, simple to use, and environmental friendly is the use of natural compounds. Consequently, we have tested the antiviral potential of different polyphenols present in plants and natural products, such as wine and tea, against WNV, ZIKV, and DENV. So that, we assayed the effect of a panel of structurally related polyphenols [delphinidin (D, cyanidin (Cy, catechin (C, epicatechin (EC, epigallocatechin (EGC, and epigallocatechin gallate (EGCG] on WNV infection, and found that D and EGCG inhibited more effectively the virus production. Further analysis with both compounds indicated that they mainly affected the attachment and entry steps of the virus life cycle. Moreover, D and EGCG showed a direct effect on WNV particles exerting a virucidal effect. We showed a similar inhibition of viral production of these compounds on WNV variants that differed on acidic pH requirements for viral fusion, indicating that their antiviral activity against WNV is produced by a virucidal effect rather than by an inhibition of pH-dependent viral fusion. Both polyphenols also reduced the infectivity of ZIKV and DENV. Therefore, D and EGCG impair the infectivity in cell culture of these three medically relevant flaviviruses.

  8. Monitoring of West Nile virus, Usutu virus and Meaban virus in waterfowl used as decoys and wild raptors in southern Spain.

    Science.gov (United States)

    Jurado-Tarifa, E; Napp, S; Lecollinet, S; Arenas, A; Beck, C; Cerdà-Cuéllar, M; Fernández-Morente, M; García-Bocanegra, I

    2016-12-01

    In the last decade, the number of emerging flaviviruses described worldwide has increased considerably, with wild birds acting as the main reservoir hosts of these viruses. We carried out an epidemiological survey to determine the seroprevalence of antigenically related flaviviruses, particularly West Nile virus (WNV), Usutu virus (USUV) and Meaban virus (MBV), in waterfowl used as decoys and wild raptors in Andalusia (southern Spain), the region considered to have the highest risk of flaviviruses circulation in Spain. The overall flaviviruses seroprevalence according to bELISA was 13.0% in both in decoys (n=1052) and wild raptors (n=123). Specific antibodies against WNV, USUV and MBV were confirmed by micro virus neutralization tests in 12, 38 and 4 of the seropositive decoys, respectively. This is the first study on WNV and USUV infections in decoys and the first report of MBV infections in waterfowl and raptors. Moreover we report the first description of WNV infections in short-toed snake eagle (Circaetus gallicus) and Montagu's harrier (Circus pygargus). The seropositivity obtained indicates widespread but not homogeneous distribution of WNV and USUV in Andalusia. The results also confirm endemic circulation of WNV, USUV and MBV in both decoys and wild raptors in southern Spain. Our results highlight the need to implement surveillance and control programs not only for WNV but also for other related flaviviruses. Further research is needed to determine the eco-epidemiological role that waterfowl and wild raptors play in the transmission of emerging flaviviruses, especially in decoys, given their close interactions with humans. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Serosurveillance for Japanese encephalitis and West Nile viruses in resident birds in Hawai'i.

    Science.gov (United States)

    Nemeth, Nicole M; Bosco-Lauth, Angela M; Sciulli, Rebecca H; Gose, Remedios B; Nagata, Mark T; Bowen, Richard A

    2010-04-01

    Japanese encephalitis virus (JEV) and West Nile virus (WNV) are emerging zoonotic arboviruses that have recently undergone intercontinental expansion. Both JEV and WNV are naturally transmitted between mosquito vectors and vertebrate reservoir hosts, including birds. A potential route of JEV introduction from Asia to western North America is via the Hawaiian archipelago, while the spread of WNV from mainland North America to Hawai'i is also considered an impending threat. We surveyed resident, non-native bird sera for antibodies to JEV and WNV on two Hawaiian Islands from 2004-2005. Three of 1,835 birds (0.16%) had evidence of antiflavivirus antibodies, demonstrating neutralizing activity to JEV and St. Louis encephalitis virus (SLEV). These detections could represent a limited transmission focus of either, or both, JEV and SLEV, or cross-reactive antibodies due to primary infection with an alternate flavivirus. Frequent air traffic from both Asia and North America to Hawai'i, along with the presence of probable competent vectors and amplifying vertebrate hosts in Hawai'i, increases the likelihood of introduction and maintenance of novel flaviviruses. Therefore, it is important to monitor for the presence of these viruses.

  10. Antithyroglobulin Antibodies and Antimicrosomal Antibodies in Various Thyroid Diseases

    International Nuclear Information System (INIS)

    Lee, Gwon Jun; Hong, Key Sak; Choi, Kang Won; Lee, Kyu; Koh, Chang Soon; Lee, Mun Ho; Park, Sung Hoe; Chi, Je Geun; Lee, Sang Kook

    1979-01-01

    The authors investigated the incidence of antithyroglobulin antibodies and antibodies and antimicrosomal antibodies measured by tanned red cell hemagglutination method in subjects suffering from various thyroid disorders. 1) In 15 normal patients, neither suffering from any thyroid diseases nor from any other autoimmune disorders, the antithyroglobulin antibodies were all negative, but the antimicrosomal antibody was positive only in one patient (6.7%). 2) The antithyroglobulin antibodies were positive in 31.5% (34 patients) of 108 patients with various thyroid diseases, and the antimicrosomal antibodies were positive in 37.0% (40 patients). 3) of the 25 patients with Graves' diseases, 7 patients (28.0%) showed positive for the antithyroglobulin antibodies, and 9 (36.0%) for the antimicrosomal antibodies. There was no definite differences in clinical and thyroid functions between the groups with positive and negative results. 4) Both antibodies were positive in 16 (88.9%) and 17 (94.4%) patients respectively among 18 patients with Hashimoto's thyroiditis, all of them were diagnosed histologically. 5) Three out of 33 patients with thyroid adenoma showed positive antibodies, and 3 of 16 patients with thyroid carcinoma revealed positive antibodies. 6) TRCH antibodies demonstrated negative results in 2 patients with subacute thyroiditis, but positive in one patient with idiopathic primary myxedema. 7) The number of patients with high titers(>l:802) was 16 for antithyroglobulin antibody, and 62.5% (10 patients) of which was Hashimoto's thyroiditis. Thirteen (65.0) of 20 patients with high titers (>l:802) for antimicrosomal antibody was Hashimoto's thyroiditis. TRCH test is a simple, sensitive method, and has high reliability and reproducibility. The incidences and titers of antithyroglobulin antibody and antimicrosomal antibody are especially high in Hashimoto's thyroiditis.

  11. Plasma homovanillic acid levels and therapeutic outcome in schizophrenics: comparisons of neuroleptic-naive first-episode patients and patients with disease exacerbation due to neuroleptic discontinuance.

    Science.gov (United States)

    Akiyama, K; Tsuchida, K; Kanzaki, A; Ujike, H; Hamamura, T; Kondo, K; Mutoh, S; Miyanagi, K; Kuroda, S; Otsuki, S

    1995-11-15

    Plasma homovanillic acid (pHVA) levels were measured and the Brief Psychiatric Rating Scale (BPRS) scores were evaluated in 26 schizophrenic patients who had either never been medicated (neuroleptic-naive, first-episode subjects) or whose condition had become exacerbated following neuroleptic discontinuance (exacerbated subjects). All the subjects received medication with a fixed dose of a neuroleptic (haloperidol or fluphenazine, both 9 mg/day) for the first week and variable doses for the subsequent 4 weeks. In the neuroleptic-naive subjects, pHVA levels increased significantly 1 week after starting the protocol; this increase correlated significantly with clinical improvement of the BPRS positive symptom scores at week 5. In the neuroleptic-naive subjects, pHVA levels had declined to the baseline level by week 5. In the exacerbated subjects, there were no significant correlations between pHVA level changes at week 1 and later improvements of the BPRS positive symptom scores. These results suggest that the rise in pHVA levels occurring within 1 week after starting a fixed neuroleptic dose may predict a favorable clinical response in neuroleptic-naive schizophrenic patients.

  12. Quantitative relationship between antibody affinity and antibody avidity

    International Nuclear Information System (INIS)

    Griswold, W.R.

    1987-01-01

    The relationship between antibody avidity, measured by the dissociation of the antigen-antibody bond in antigen excess, and antibody affinity was studied. Complexes of radiolabelled antigen and antibody of known affinity were prepared in vitro and allowed to stand for seven days to reach equilibrium. Then nonlabelled antigen in one hundred fold excess was added to dissociate the complexes. After an appropriate incubation the fraction of antigen bound to antibody was measured by the ammonium sulfate precipitation method. The dissociation index was the fraction bound in the experimental sample divided by the fraction bound in the control. The correlation coefficient between the dissociation index and the antibody binding constant was 0.92 for early dissociation and 0.98 for late dissociation. The regression equation relating the binding constant to the dissociation index was K = 6.4(DI) + 6.25, where DI is the late dissociation index and K is the logarithm to the base 10 of the binding constant. There is a high correlation between avidity and affinity of antibody. Antibody affinity can be estimated from avidity data. The stability of antigen-antibody complexes can be predicted from antibody affinity

  13. Comparative analysis of drug resistance mutations in the human immunodeficiency virus reverse transcriptase gene in patients who are non-responsive, responsive and naive to antiretroviral therapy.

    Science.gov (United States)

    Misbah, Mohammad; Roy, Gaurav; Shahid, Mudassar; Nag, Nalin; Kumar, Suresh; Husain, Mohammad

    2016-05-01

    Drug resistance mutations in the Pol gene of human immunodeficiency virus 1 (HIV-1) are one of the critical factors associated with antiretroviral therapy (ART) failure in HIV-1 patients. The issue of resistance to reverse transcriptase inhibitors (RTIs) in HIV infection has not been adequately addressed in the Indian subcontinent. We compared HIV-1 reverse transcriptase (RT) gene sequences to identify mutations present in HIV-1 patients who were ART non-responders, ART responders and drug naive. Genotypic drug resistance testing was performed by sequencing a 655-bp region of the RT gene from 102 HIV-1 patients, consisting of 30 ART-non-responding, 35 ART-responding and 37 drug-naive patients. The Stanford HIV Resistance Database (HIVDBv 6.2), IAS-USA mutation list, ANRS_09/2012 algorithm, and Rega v8.02 algorithm were used to interpret the pattern of drug resistance. The majority of the sequences (96 %) belonged to subtype C, and a few of them (3.9 %) to subtype A1. The frequency of drug resistance mutations observed in ART-non-responding, ART-responding and drug-naive patients was 40.1 %, 10.7 % and 20.58 %, respectively. It was observed that in non-responders, multiple mutations were present in the same patient, while in responders, a single mutation was found. Some of the drug-naive patients had more than one mutation. Thymidine analogue mutations (TAMs), however, were found in non-responders and naive patients but not in responders. Although drug resistance mutations were widely distributed among ART non-responders, the presence of resistance mutations in the viruses of drug-naive patients poses a big concern in the absence of a genotyping resistance test.

  14. Acute cognitive impact of antiseizure drugs in naive rodents and corneal-kindled mice.

    Science.gov (United States)

    Barker-Haliski, Melissa L; Vanegas, Fabiola; Mau, Matthew J; Underwood, Tristan K; White, H Steve

    2016-09-01

    Some antiseizure drugs (ASDs) are associated with cognitive liability in patients with epilepsy, thus ASDs without this risk would be preferred. Little comparative pharmacology exists with ASDs in preclinical models of cognition. Few pharmacologic studies exist on the acute effects in rodents with chronic seizures. Predicting risk for cognitive impact with preclinical models may supply valuable ASD differentiation data. ASDs (phenytoin [PHT]; carbamazepine [CBZ]; valproic acid [VPA]; lamotrigine [LTG]; phenobarbital [PB]; tiagabine [TGB]; retigabine [RTG]; topiramate [TPM]; and levetiracetam [LEV]) were administered equivalent to maximal electroshock median effective dose ([ED50]; mice, rats), or median dose necessary to elicit minimal motor impairment (median toxic dose [TD50]; rats). Cognition models with naive adult rodents were novel object/place recognition (NOPR) task with CF-1 mice, and Morris water maze (MWM) with Sprague-Dawley rats. Selected ASDs were also administered to rats prior to testing in an open field. The effect of chronic seizures and ASD administration on cognitive performance in NOPR was also determined with corneal-kindled mice. Mice that did not achieve kindling criterion (partially kindled) were included to examine the effect of electrical stimulation on cognitive performance. Sham-kindled and age-matched mice were also tested. No ASD (ED50) affected latency to locate the MWM platform; TD50 of PB, RTG, TPM, and VPA reduced this latency. In naive mice, CBZ and VPA (ED50) reduced time with the novel object. Of interest, no ASD (ED50) affected performance of fully kindled mice in NOPR, whereas CBZ and LEV improved cognitive performance of partially kindled mice. Standardized approaches to the preclinical evaluation of an ASD's potential cognitive impact are needed to inform drug development. This study demonstrated acute, dose- and model-dependent effects of therapeutically relevant doses of ASDs on cognitive performance of naive mice and

  15. Potent neutralization of VEGF biological activities with a fully human antibody Fab fragment directed against VEGF receptor 2

    International Nuclear Information System (INIS)

    Miao, H.-Q.; Hu, Kun; Jimenez, Xenia; Navarro, Elizabeth; Zhang, Haifan; Lu Dan; Ludwig, Dale L.; Balderes, Paul; Zhu Zhenping

    2006-01-01

    Compelling evidence suggest that vascular endothelial growth factor (VEGF) and its receptors, especially receptor 2 (VEGFR2, or kinase insert domain-containing receptor, KDR), play a critical role in angiogenesis under both physiological and pathological conditions, including cancer and angiogenic retinopathies such as age-related macular degeneration (AMD). To this end, inhibition of angiogenesis with antagonists to either VEGF or KDR has yielded significant therapeutic efficacy both in preclinical studies in animal models and in clinical trials in patients with cancer and AMD. We previously reported the identification of a high affinity, fully human anti-KDR antibody fragment, 1121B Fab, through a highly stringent affinity maturation process with a Fab originally isolated from a naive human antibody phage display library. In this study, we demonstrate that 1121B Fab is able to strongly block KDR/VEGF interaction, resulting in potent inhibition of an array of biological activities of VEGF, including activation of the receptor and its signaling pathway, intracellular calcium mobilization, and migration and proliferation of endothelial cells. Taken together, our data lend strong support to the further development of 1121B Fab fragment as an anti-angiogenesis agent in both cancer and angiogenic retinopathies

  16. Antithyroglobulin Antibodies and Antimicrosomal Antibodies in Various Thyroid Diseases

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Gwon Jun; Hong, Key Sak; Choi, Kang Won; Lee, Kyu; Koh, Chang Soon; Lee, Mun Ho; Park, Sung Hoe; Chi, Je Geun; Lee, Sang Kook [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1979-03-15

    The authors investigated the incidence of antithyroglobulin antibodies and antibodies and antimicrosomal antibodies measured by tanned red cell hemagglutination method in subjects suffering from various thyroid disorders. 1) In 15 normal patients, neither suffering from any thyroid diseases nor from any other autoimmune disorders, the antithyroglobulin antibodies were all negative, but the antimicrosomal antibody was positive only in one patient (6.7%). 2) The antithyroglobulin antibodies were positive in 31.5% (34 patients) of 108 patients with various thyroid diseases, and the antimicrosomal antibodies were positive in 37.0% (40 patients). 3) of the 25 patients with Graves' diseases, 7 patients (28.0%) showed positive for the antithyroglobulin antibodies, and 9 (36.0%) for the antimicrosomal antibodies. There was no definite differences in clinical and thyroid functions between the groups with positive and negative results. 4) Both antibodies were positive in 16 (88.9%) and 17 (94.4%) patients respectively among 18 patients with Hashimoto's thyroiditis, all of them were diagnosed histologically. 5) Three out of 33 patients with thyroid adenoma showed positive antibodies, and 3 of 16 patients with thyroid carcinoma revealed positive antibodies. 6) TRCH antibodies demonstrated negative results in 2 patients with subacute thyroiditis, but positive in one patient with idiopathic primary myxedema. 7) The number of patients with high titers(>l:802) was 16 for antithyroglobulin antibody, and 62.5% (10 patients) of which was Hashimoto's thyroiditis. Thirteen (65.0) of 20 patients with high titers (>l:802) for antimicrosomal antibody was Hashimoto's thyroiditis. TRCH test is a simple, sensitive method, and has high reliability and reproducibility. The incidences and titers of antithyroglobulin antibody and antimicrosomal antibody are especially high in Hashimoto's thyroiditis.

  17. ROLE OF CD95 AND DR3 RECEPTORS IN NA VE T-LYMPHOCYTES APOPTOSIS IN CHILDREN WITH INFECTIOUS MONONUCLEOSIS DURING CONVALESCENCE

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    E. N. Filatova

    2017-01-01

    Full Text Available Infectious mononucleosis is a widespread disease caused by certain members of Herpesviridae family. Acute infectious mononucleosis develops predominantly in children and is accompanied by an increase of the number of circulating naive CD4+ and naive CD8+ T-lymphocytes in the peripheral blood. The normalization of immunological parameters is achieved within 4–6 months after recovery and that is an indicator of a proper functioning of the immune system. CD95 and DR3 death receptors are involved in the initiation of apoptosis of naive T-lymphocytes in healthy people and in patients with infectious mononucleosis. The aim of the study was to evaluate the ability of CD95 and DR3 receptors to initiate apoptosis of naive CD4+ and naive CD8+ T-lymphocytes in children with infectious mononucleosis during convalescence. The material for the study was the samples of the peripheral blood of children who previously had infectious mononucleosis. The blood sampling was carried out again after 4–6 months after the disease. At the time of the study, children did not display clinical and laboratory signs of infectious mononucleosis. Same children who were examined earlier in the period of the development of acute infectious mononucleosis, as well as relatively healthy children were used as the comparison groups. Isolation of naive CD4+ and naive CD8+ T-lymphocytes was performed by negative magnetic immunoseparation. For specific stimulation of CD95 and DR3 receptors monoclonal antibodies were used. The level of apoptosis and expression of death receptors were evaluated by flow cytometry. Freshly isolated cells were analyzed, as well as cells cultured with the addition of appropriate monoclonal antibodies. It was shown that the recovery period was accompanied by increased apoptosis of freshly isolated naive CD4+ and naive CD8+ T-lymphocytes compared with the acute phase of infectious mononucleosis. Thus in both populations of naive T-cells showed an increase of

  18. Comparative study of clozapine versus risperidone in treatment-naive, first-episode schizophrenia: A pilot study

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    Sukhtej Sahni

    2016-01-01

    Interpretation & conclusions: The findings of this preliminary study showed clozapine as a better choice than risperidone in terms of efficacy, tolerability and better quality of life in treatment-naive, first-episode schizophrenia. However, further studies need to be done on a larger group of patients to confirm the findings.

  19. Naive T lymphocytes traffic to inflamed central nervous system, but require antigen recognition for activation

    DEFF Research Database (Denmark)

    Krakowski, M L; Owens, T

    2000-01-01

    Organ-specific autoimmune diseases may be induced by infiltration of the target tissue by CD4(+) T cells with specificity for self antigen(s). As disease progresses, T cells of other specificities appear in the tissue. Traffic of naive, antigen-inexperienced T cells to target tissues has not been...

  20. Performance evaluation of a motor-imagery-based EEG-Brain computer interface using a combined cue with heterogeneous training data in BCI-Naive subjects

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    Lee Youngbum

    2011-10-01

    Full Text Available Abstract Background The subjects in EEG-Brain computer interface (BCI system experience difficulties when attempting to obtain the consistent performance of the actual movement by motor imagery alone. It is necessary to find the optimal conditions and stimuli combinations that affect the performance factors of the EEG-BCI system to guarantee equipment safety and trust through the performance evaluation of using motor imagery characteristics that can be utilized in the EEG-BCI testing environment. Methods The experiment was carried out with 10 experienced subjects and 32 naive subjects on an EEG-BCI system. There were 3 experiments: The experienced homogeneous experiment, the naive homogeneous experiment and the naive heterogeneous experiment. Each experiment was compared in terms of the six audio-visual cue combinations and consisted of 50 trials. The EEG data was classified using the least square linear classifier in case of the naive subjects through the common spatial pattern filter. The accuracy was calculated using the training and test data set. The p-value of the accuracy was obtained through the statistical significance test. Results In the case in which a naive subject was trained by a heterogeneous combined cue and tested by a visual cue, the result was not only the highest accuracy (p Conclusions We propose the use of this measuring methodology of a heterogeneous combined cue for training data and a visual cue for test data by the typical EEG-BCI algorithm on the EEG-BCI system to achieve effectiveness in terms of consistence, stability, cost, time, and resources management without the need for a trial and error process.

  1. Strain differences in the neural, behavioral, and molecular correlates of sweet and salty taste in naive, ethanol- and sucrose-exposed P and NP rats.

    Science.gov (United States)

    Coleman, Jamison; Williams, Ashley; Phan, Tam-Hao T; Mummalaneni, Shobha; Melone, Pamela; Ren, Zuojun; Zhou, Huiping; Mahavadi, Sunila; Murthy, Karnam S; Katsumata, Tadayoshi; DeSimone, John A; Lyall, Vijay

    2011-11-01

    Strain differences between naive, sucrose- and ethanol-exposed alcohol-preferring (P) and alcohol-nonpreferring (NP) rats were investigated in their consumption of ethanol, sucrose, and NaCl; chorda tympani (CT) nerve responses to sweet and salty stimuli; and gene expression in the anterior tongue of T1R3 and TRPV1/TRPV1t. Preference for 5% ethanol and 10% sucrose, CT responses to sweet stimuli, and T1R3 expression were greater in naive P rats than NP rats. The enhancement of the CT response to 0.5 M sucrose in the presence of varying ethanol concentrations (0.5-40%) in naive P rats was higher and shifted to lower ethanol concentrations than NP rats. Chronic ingestion of 5% sucrose or 5% ethanol decreased T1R3 mRNA in NP and P rats. Naive P rats also demonstrated bigger CT responses to NaCl+benzamil and greater TRPV1/TRPV1t expression. TRPV1t agonists produced biphasic effects on NaCl+benzamil CT responses, enhancing the response at low concentrations and inhibiting it at high concentrations. The concentration of a TRPV1/TRPV1t agonist (Maillard reacted peptides conjugated with galacturonic acid) that produced a maximum enhancement in the NaCl+benzamil CT response induced a decrease in NaCl intake and preference in P rats. In naive P rats and NP rats exposed to 5% ethanol in a no-choice paradigm, the biphasic TRPV1t agonist vs. NaCl+benzamil CT response profiles were higher and shifted to lower agonist concentrations than in naive NP rats. TRPV1/TRPV1t mRNA expression increased in NP rats but not in P rats exposed to 5% ethanol in a no-choice paradigm. We conclude that P and NP rats differ in T1R3 and TRPV1/TRPV1t expression and neural and behavioral responses to sweet and salty stimuli and to chronic sucrose and ethanol exposure.

  2. HIV-1 integrase resistance among antiretroviral treatment naive and experienced patients from Northwestern Poland

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    Parczewski Miłosz

    2012-12-01

    Full Text Available Abstract Background HIV integrase inhibitor use is limited by low genetic barrier to resistance and possible cross-resistance among representatives of this class of antiretrovirals. The aim of this study was to analyse integrase sequence variability among antiretroviral treatment naive and experienced patients with no prior integrase inhibitor (InI exposure and investigate development of the InI drug resistance mutations following the virologic failure of the raltegravir containing regimen. Methods Sequencing of HIV-1 integrase region from plasma samples of 80 integrase treatment naive patients and serial samples from 12 patients with observed virologic failure on raltegravir containing treatment whenever plasma vireamia exceeded >50 copies/ml was performed. Drug resistance mutations were called with Stanford DB database and grouped into major and minor variants. For subtyping bootstrapped phylogenetic analysis was used; Bayesian Monte Carlo Marcov Chain (MCMC model was implemented to infer on the phylogenetic relationships between the serial sequences from patients failing on raltegravir. Results Majority of the integrase region sequences were classified as subtype B; the remaining ones being subtype D, C, G, as well as CRF01_AE , CRF02_AG and CRF13_cpx recombinants. No major integrase drug resistance mutations have been observed in InI-treatment naive patients. In 30 (38.5% cases polymorphic variation with predominance of the E157Q mutation was observed. This mutation was more common among subtype B (26 cases, 54.2% than non-B sequences (5 cases, 16.7%, p=0.00099, OR: 5.91 (95% CI:1.77-22.63]. Other variants included L68V, L74IL, T97A, E138D, V151I, R263K. Among 12 (26.1% raltegravir treated patients treatment failure was observed; major InI drug resistance mutations (G140S, Q148H and N155H, V151I, E92EQ, V151I, G163R were noted in four of these cases (8.3% of the total InI-treated patients. Time to the development of drug resistance ranged

  3. IMPLEMENTASI AUGMENTED REALITY UNTUK IDENTIFIKASI LOGO DAN VIDEO SEBAGAI MEDIA INFORMASI MENGGUNAKAN METODE KLASIFIKASI NAIVE BAYESIAN

    Directory of Open Access Journals (Sweden)

    Astrid Novita Putri

    2018-04-01

    Full Text Available Pada  Universitas Semarang Fakultas Teknologi Informasi dan  Komunikasi setiap  tahun  selalu mempunyai banyak kegiatan seperti kegiatan Seminar, Workshop, Pelatihan, Festifal, dsb. Kegiatan- kegiatan  tersebut  biasanya   didokumentasikan  dalam  bentuk  foto   dan   video.   Sedangkan  untuk dokumentasi publikasi kegiatan dalam bentuk media promosi maupun media informasi belum dilakukan, sehingga masyarakat umum yang kurang familiar tidak dapat mengetahui informasi dengan kegiatan yang ada. Memanfaatkan aplikasi smartphone yang berbasis android, blackberry, dan iphone dapat menggunakan  salah  satu  teknologi  augmented  reality  3D  yang  berfungsi  untuk  mengidentifikasi informasi melalui logo Fakultas TIK dan menerapkannya pada berbagai media cetak atau elektronik. Sehingga dengan adanya perubahan cara promosi tersebut diharapkan dapat menarik minat perhatian masyarakat umum dan masyarakat umum untuk mengetahui informasi mengenai kegiatan di Universitas Semarang khususnya Fakultas Teknologi Informasi dan Komunikasi. Pada penelitian ini, akan membahas bagaimana mengklasifikasikan kegiatan-kegiatan tersebut menggunakan metode naive bayes   menjadi dua  kategori yaitu favorit atau tidak favorit. Berdasarkan data foto dan video kegiatan FTIK tahun 2017 yang telah diimplementasikan menggunakan tools Unity 3D menunjukkan bahwa penerapan Augmented Reality untuk identifikasi logo sebagai media informasi menggunakan metode klasifikasi naive bayes dapat diimplementasikan dengan baik. Diharapkan dengan adanya klasifikasi kegiatan dengan memanfaatkan teknologi  augmented  reality  yang  diimplementasikan menggunakan  tools  Unity  3D, informasi yang dihasilkan akan lebih informatif dan menarik perhatian masyarakat umum.   Kata kunci: augmented, reality, naive, bayesian, kegiatan.

  4. A preliminary randomized double blind placebo-controlled trial of intravenous immunoglobulin for Japanese encephalitis in Nepal.

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    Ajit Rayamajhi

    Full Text Available Japanese encephalitis (JE virus (JEV is a mosquito-borne flavivirus found across Asia that is closely related to West Nile virus. There is no known antiviral treatment for any flavivirus. Results from in vitro studies and animal models suggest intravenous immunoglobulin (IVIG containing virus-specific neutralizing antibody may be effective in improving outcome in viral encephalitis. IVIG's anti-inflammatory properties may also be beneficial.We performed a pilot feasibility randomized double-blind placebo-controlled trial of IVIG containing anti-JEV neutralizing antibody (ImmunoRel, 400mg/kg/day for 5 days in children with suspected JE at two sites in Nepal; we also examined the effect on serum neutralizing antibody titre and cytokine profiles. 22 children were recruited, 13 of whom had confirmed JE; 11 received IVIG and 11 placebo, with no protocol violations. One child (IVIG group died during treatment and two (placebo subsequently following hospital discharge. Overall, there was no difference in outcome between treatment groups at discharge or follow up. Passive transfer of anti-JEV antibody was seen in JEV negative children. JEV positive children treated with IVIG had JEV-specific neutralizing antibody titres approximately 16 times higher than those treated with placebo (p=0.2, which was more than could be explained by passive transfer alone. IL-4 and IL-6 were higher in the IVIG group.A trial of IVIG for JE in Nepal is feasible. IVIG may augment the development of neutralizing antibodies in JEV positive patients. IVIG appears an appealing option for JE treatment that warrants further study.ClinicalTrials.gov NCT01856205.

  5. Application of a naive Bayesians classifiers in assessing the supplier

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    Mijailović Snežana

    2017-01-01

    Full Text Available The paper considers the class of interactive knowledge based systems whose main purpose of making proposals and assisting customers in making decisions. The mathematical model provides a set of examples of learning about the delivered series of outflows from three suppliers, as well as an analysis of an illustrative example for assessing the supplier using a naive Bayesian classifier. The model was developed on the basis of the analysis of subjective probabilities, which are later revised with the help of new empirical information and Bayesian theorem on a posterior probability, i.e. combining of subjective and objective conditional probabilities in the choice of a reliable supplier.

  6. No change of dopamine transporter density in basal ganglia after risperidone treatment in drug-naive children with Tourette's disorder

    International Nuclear Information System (INIS)

    Ryu, W. K.; Ryu, Y. H.; Yoon, M. J.; Chun, K. A.; Lee, J. D.; Zee, D. Y.; Choi, T. H.

    2003-01-01

    Tourette's disorder (TD), which is characterized by multiple waxing and waning motor tics and one or more vocal tics, is known to be associated with abnormalities in the dopaminergic system. To testify our hypothesis that risperidone would improve tic symptoms of TD patients through the change of the dopaminergic system, we measured the DAT densities between drug-naive children with TD and normal children investigated the DAT density before and after treatment with risperidone in drug-naive children with TD, using lodine-123 labelled N-(3-iodopropen-2-yl)-2beta-carbomethoxy-3beta-(4-chlorophenyl) tropane(I-123 IPT) single photon emission computed tomography (SPECT). I-123 IPT SPECT imaging and Yale Global Tic Severity Scale-Korean version (YGTSS-K) for assessing the tic symptom severity were carried out before and after treatment with risperidone for 8 weeks in eight drug-naive children with TD. Eight normal children also underwent SPECT imaging 2 hours after an intravenous administration of I-123 IPT and carried out both quantitative and qualitative analyses using the obtained SPECT data, which were reconstructed for the assessment of the specific/non-specific DAT binding ratio in the basal ganglia. The drug-naive children with TD had a significantly greater increase in the specific/nonspecific DAT binding ratio of both basal ganglia compared with the normal children. However, no significant difference in the specific/nonspecific DAT binding ratio of the basal ganglia before and after treatment with riperidone in children with TD was not found, although tic symptoms were significantly improved with risperidone. These findings suggest that DAT densities are directly associated with the pathophysiology of TD, however, that the effect of risperidone on tic symptoms in children with TD is not attributed to the change of dopaminergic system

  7. Reduced error signalling in medication-naive children with ADHD

    DEFF Research Database (Denmark)

    Plessen, Kerstin J; Allen, Elena A; Eichele, Heike

    2016-01-01

    BACKGROUND: We examined the blood-oxygen level-dependent (BOLD) activation in brain regions that signal errors and their association with intraindividual behavioural variability and adaptation to errors in children with attention-deficit/hyperactivity disorder (ADHD). METHODS: We acquired...... functional MRI data during a Flanker task in medication-naive children with ADHD and healthy controls aged 8-12 years and analyzed the data using independent component analysis. For components corresponding to performance monitoring networks, we compared activations across groups and conditions...... and correlated them with reaction times (RT). Additionally, we analyzed post-error adaptations in behaviour and motor component activations. RESULTS: We included 25 children with ADHD and 29 controls in our analysis. Children with ADHD displayed reduced activation to errors in cingulo-opercular regions...

  8. Novel genetic susceptibility loci for diabetic end-stage renal disease identified through robust naive Bayes classification

    DEFF Research Database (Denmark)

    Sambo, Francesco; Malovini, Alberto; Sandholm, Niina

    2014-01-01

    in diabetic patients. Our aim was to detect novel genetic variants associated with diabetic nephropathy and ESRD. METHODS: We exploited a novel algorithm, 'Bag of Naive Bayes', whose marker selection strategy is complementary to that of conventional genome-wide association models based on univariate...

  9. The F4/AS01B HIV-1 Vaccine Candidate Is Safe and Immunogenic, But Does Not Show Viral Efficacy in Antiretroviral Therapy-Naive, HIV-1-Infected Adults: A Randomized Controlled Trial.

    Science.gov (United States)

    Dinges, Warren; Girard, Pierre-Marie; Podzamczer, Daniel; Brockmeyer, Norbert H; García, Felipe; Harrer, Thomas; Lelievre, Jean-Daniel; Frank, Ian; Colin De Verdière, Nathalie; Yeni, Guy-Patrick; Ortega Gonzalez, Enrique; Rubio, Rafael; Clotet Sala, Bonaventura; DeJesus, Edwin; Pérez-Elias, Maria Jesus; Launay, Odile; Pialoux, Gilles; Slim, Jihad; Weiss, Laurence; Bouchaud, Olivier; Felizarta, Franco; Meurer, Anja; Raffi, François; Esser, Stefan; Katlama, Christine; Koletar, Susan L; Mounzer, Karam; Swindells, Susan; Baxter, John D; Schneider, Stefan; Chas, Julie; Molina, Jean-Michel; Koutsoukos, Marguerite; Collard, Alix; Bourguignon, Patricia; Roman, François

    2016-02-01

    The impact of the investigational human immunodeficiency virus type 1 (HIV-1) F4/AS01B vaccine on HIV-1 viral load (VL) was evaluated in antiretroviral therapy (ART)-naive HIV-1 infected adults.This phase IIb, observer-blind study (NCT01218113), included ART-naive HIV-1 infected adults aged 18 to 55 years. Participants were randomized to receive 2 (F4/AS01B_2 group, N = 64) or 3 (F4/AS01B_3 group, N = 62) doses of F4/AS01B or placebo (control group, N = 64) at weeks 0, 4, and 28. Efficacy (HIV-1 VL, CD4 T-cell count, ART initiation, and HIV-related clinical events), safety, and immunogenicity (antibody and T-cell responses) were evaluated during 48 weeks.At week 48, based on a mixed model, no statistically significant difference in HIV-1 VL change from baseline was demonstrated between F4/AS01B_2 and control group (0.073 log10 copies/mL [97.5% confidence interval (CI): -0.088; 0.235]), or F4/AS01B_3 and control group (-0.096 log10 copies/mL [97.5% CI: -0.257; 0.065]). No differences between groups were observed in HIV-1 VL change, CD4 T-cell count, ART initiation, or HIV-related clinical events at intermediate timepoints. Among F4/AS01B recipients, the most frequent solicited symptoms were pain at injection site (252/300 doses), fatigue (137/300 doses), myalgia (105/300 doses), and headache (90/300 doses). Twelve serious adverse events were reported in 6 participants; 1 was considered vaccine-related (F4/AS01B_2 group: angioedema). F4/AS01B induced polyfunctional F4-specific CD4 T-cells, but had no significant impact on F4-specific CD8 T-cell and anti-F4 antibody levels.F4/AS01B had a clinically acceptable safety profile, induced F4-specific CD4 T-cell responses, but did not reduce HIV-1 VL, impact CD4 T-cells count, delay ART initiation, or prevent HIV-1 related clinical events.

  10. Classical Swine Fever Outbreak after Modified Live LOM Strain Vaccination in Naive Pigs, South Korea

    Science.gov (United States)

    Je, Sang H.; Kwon, Taeyong; Yoo, Sung J.; Lee, Dong-Uk; Lee, SeungYoon; Richt, Juergen A.

    2018-01-01

    We report classical swine fever outbreaks occurring in naive pig herds on Jeju Island, South Korea, after the introduction of the LOM vaccine strain. Two isolates from sick pigs had >99% identity with the vaccine stain. LOM strain does not appear safe; its use in the vaccine should be reconsidered. PMID:29553332

  11. Telomere Elongation and Naive Pluripotent Stem Cells Achieved from Telomerase Haplo-Insufficient Cells by Somatic Cell Nuclear Transfer

    Directory of Open Access Journals (Sweden)

    Li-Ying Sung

    2014-12-01

    Full Text Available Summary: Haplo-insufficiency of telomerase genes in humans leads to telomere syndromes such as dyskeratosis congenital and idiopathic pulmonary fibrosis. Generation of pluripotent stem cells from telomerase haplo-insufficient donor cells would provide unique opportunities toward the realization of patient-specific stem cell therapies. Recently, pluripotent human embryonic stem cells (ntESCs have been efficiently achieved by somatic cell nuclear transfer (SCNT. We tested the hypothesis that SCNT could effectively elongate shortening telomeres of telomerase haplo-insufficient cells in the ntESCs with relevant mouse models. Indeed, telomeres of telomerase haplo-insufficient (Terc+/− mouse cells are elongated in ntESCs. Moreover, ntESCs derived from Terc+/− cells exhibit naive pluripotency as evidenced by generation of Terc+/− ntESC clone pups by tetraploid embryo complementation, the most stringent test of naive pluripotency. These data suggest that SCNT could offer a powerful tool to reprogram telomeres and to discover the factors for robust restoration of telomeres and pluripotency of telomerase haplo-insufficient somatic cells. : Sung et al. demonstrate in a mouse model that telomeres of telomerase haplo-insufficient cells can be elongated by somatic cell nuclear transfer. Moreover, ntESCs derived from Terc+/− cells exhibit pluripotency evidenced by generation of Terc+/−ntESC clone pups by tetraploid embryo complementation, the most stringent test of naive pluripotency.

  12. Naive helper T cells from BCG-vaccinated volunteers produce IFN-gamma and IL-5 to mycobacterial antigen-pulsed dendritic cells.

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    JoĂŤl Pestel

    2008-06-01

    Full Text Available Mycobacterium bovis bacillus Calmette-GuĂŠrin (BCG is a live vaccine that has been used in routine vaccination against tuberculosis for nearly 80 years. However, its efficacy is controversial. The failure of BCG vaccination may be at least partially explained by the induction of poor or inappropriate host responses. Dendritic cells (DCs are likely to play a key role in the induction of immune response to mycobacteria by polarizing the reactivity of T lymphocytes toward a Th1 profile, contributing to the generation of protective cellular immunity against mycobacteria. In this study we aimed to investigate the production of Th1 and Th2 cytokines by naive CD4+ T cells to mycobacterial antigen-pulsed DCs in the group of young, healthy BCG vaccinated volunteers. The response of naive helper T cells was compared with the response of total blood lymphocytes. Our present results clearly showed that circulating naive CD45RA+CD4+ lymphocytes from BCG-vaccinated subjects can become effector helper cells producing IFN-gamma and IL-5 under the stimulation by autologous dendritic cells presenting mycobacterial protein antigen-PPD or infected with live M. bovis BCG bacilli.

  13. Naive helper T cells from BCG-vaccinated volunteers produce IFN-gamma and IL-5 to mycobacterial antigen-pulsed dendritic cells.

    Science.gov (United States)

    Kowalewicz-Kulbat, Magdalena; Kaźmierczak, Dominik; Donevski, Stefan; Biet, Franck; Pestel, Joël; Rudnicka, Wiesława

    2008-01-01

    Mycobacterium bovis bacillus Calmette-Guérin (BCG) is a live vaccine that has been used in routine vaccination against tuberculosis for nearly 80 years. However, its efficacy is controversial. The failure of BCG vaccination may be at least partially explained by the induction of poor or inappropriate host responses. Dendritic cells (DCs) are likely to play a key role in the induction of immune response to mycobacteria by polarizing the reactivity of T lymphocytes toward a Th1 profile, contributing to the generation of protective cellular immunity against mycobacteria. In this study we aimed to investigate the production of Th1 and Th2 cytokines by naive CD4+ T cells to mycobacterial antigen-pulsed DCs in the group of young, healthy BCG vaccinated volunteers. The response of naive helper T cells was compared with the response of total blood lymphocytes. Our present results clearly showed that circulating naive CD45RA+CD4+ lymphocytes from BCG-vaccinated subjects can become effector helper cells producing IFN-gamma and IL-5 under the stimulation by autologous dendritic cells presenting mycobacterial protein antigen-PPD or infected with live M. bovis BCG bacilli.

  14. [Study of anti-idiotype antibodies to human monoclonal antibody].

    Science.gov (United States)

    Harada, R; Takahashi, N; Owaki, I; Kannagi, R; Endo, N; Morita, N; Inoue, M

    1992-02-01

    A human monoclonal antibody, ll-50 (IgM, lambda), was generated, which reacted specifically with a major of glycolipid present in LS174T colon cancer cells. The glycolipid antigen which reacted with the ll-50 antibody was expected to four sugar residues from its TLC mobility, and it was ascertained that the glycolipid antigen which reacted with ll-50 antibody might be Lc4 antigen [Gal beta 1----3 GLcNAc beta 1----3 Gal beta 1----4 Glc beta 1----1 Cer] judging from TLC immunostaining and ELISA when the reactivity of ll-50 antibody was tested using various pure glycolipids in 3-5 sugar residues as an antigen. Sera in patients with malignant disorders and healthy individuals were analyzed by Sandwich assay of immobilized and biotinylated ll-50 antibody. The serum of the Lc4 antigen recognized by ll-50 antibody was significantly higher in patients with malignant disorders than that in healthy individuals (p less than 0.05). Three mouse monoclonal anti-idiotype antibodies, G3, B3 and C5 (all IgG1), were generated by the immunization of BALB/c mice with ll-50 antibody. These anti-idiotype antibodies specifically bound to to human monoclonal antibody, ll-50 and had a significant inhibitory activity towards the binding of ll-50 antibody to the Lc4 antigen. This indicated that these anti-idiotype antibodies, G3, B3, and C5, were paratope-related anti-idiotype antibodies. G3, B3, and C5 were expected to define the nearest idiotope because they could mutually inhibit ll-50 antibody. Sera in patients with malignant disorders and healthy individuals were analyzed by Sandwich assay of immobilized and biotinylated anti-idiotype antibodies, G3, B3, and C5. As to the ll-50 like antibodies defined by C5 (Id-C5+), the mean serum level in patients with malignant disorders was significantly higher than that in healthy individuals (p less than 0.05). As to the ll-50 like antibodies defined by B3 (Id-B3+), the mean serum level in patients with malignant disorders was significantly higher

  15. Recently activated naive CD4 T cells can help resting B cells, and can produce sufficient autocrine IL-4 to drive differentiation to secretion of T helper 2-type cytokines.

    Science.gov (United States)

    Croft, M; Swain, S L

    1995-05-01

    Development of T cells during primary responses was investigated using pigeon cytochrome C-specific naive Th from TCR transgenic mice. Naive CD4 cells did not activate and help resting B cells. This failure was found to be primarily because the resting B cells were incapable of stimulating the naive Th. Provision of a costimulatory signal such as anti-CD28, or addition of APCs that express costimulatory molecules, such as dendritic cells, activated B cells, and B7+ and B7+ICAM(+)-expressing fibroblasts, induced naive Th activation and promoted T cell-dependent help for IgM secretion. T cell activation for as little as 24 h promoted helper activity, and Ig secretion required production of small amounts of IL-4 by the activated naive Th. On initial stimulation, naive Th secrete only IL-2. By mRNA analysis, activated naive Th were also shown to produce IL-4, however induction of IL-4 message only occurred 24 h after initial activation and required additional stimulation with Ag. A single exposure of naive CD4 to Ag/APC followed by 4 to 12 days in culture led to generation of effector Th which secreted IL-2 and some IFN-gamma, and no detectable IL-4 or IL-5, and which could only help B cells to IgM secretion. In contrast, similar cultures that received Ag/APC one or more times during this period generated effector cells capable of secreting easily detectable titers of IL-4 and IL-5, as well as IL-2 and IFN-gamma, and able to now promote IgG1 and IgE responses. Generation of these Th0-like effectors was accompanied by increasing amounts of IL-4 secreted during the culture period after each restimulation, and addition of anti-IL-4 in culture inhibited development of the capacity to produce Th2 cytokines. These studies reinforce the notion that naive CD4 must interact with a costimulatory professional APC, rather than a resting B cell, for initiation of the primary response, but show that such an interaction can result in rapid development of the ability to interact with

  16. Characteristic appearances of fundus autofluorescence in treatment-naive and active polypoidal choroidal vasculopathy: a retrospective study of 170 patients.

    Science.gov (United States)

    Zhao, Xinyu; Xia, Song; Chen, Youxin

    2018-06-01

    To investigate the characteristic appearances of fundus autofluorescence (FAF) in patients with treatment-naive and active polypoidal choroidal vasculopathy (PCV). Cases with the diagnosis of treatment-naive and active PCV from November 2012 to May 2017 at Peking Union Medical College Hospital were retrospectively reviewed. All patients underwent comprehensive ophthalmologic examination. Autofluorescence (AF) findings were described at the retinal sites of the corresponding lesions identified and diagnosed using indocyanine green angiography and spectral-domain optical coherence tomography. One hundred seventy patients with 192 affected eyes were included. The logMAR BCVA of the patients were 0.53 ± 0.28. The six AF patterns of 243 polypoidal lesions were confluent hypo-AF with hyper-AF ring (49.8%), confluent hypo-AF (22.6%), hyper-AF with hypo-AF ring (3.7%), granular hypo-AF (7.0%), blocked hypo-AF due to hemorrhage (8.6%), and polyps without apparent AF changes (8.2%). For 146 branching vascular networks (BVNs), 97.3% were granular hypo-AF, and others were blocked hypo-AF due to hemorrhage. In eyes with treatment-naive and active PCV, the polypoidal lesions and BVNs induce characteristic FAF changes. FAF images provide reliable adjunct reference for the diagnosis of PCV.

  17. Prevalence of Intestinal Parasitic Infection among HIV Positive Persons Who Are Naive and on Antiretroviral Treatment in Hiwot Fana Specialized University Hospital, Eastern Ethiopia

    OpenAIRE

    Teklemariam, Zelalem; Abate, Degu; Mitiku, Habtamu; Dessie, Yadeta

    2013-01-01

    Background. Intestinal parasitic infection affects the health and quality of life of people living with HIV. This study was aimed to determine the prevalence of intestinal parasites among HIV positive individuals who are naive and who are on antiretroviral treatment (ART) in Hiwot Fana Specialized University Hospital, Eastern Ethiopia. Methods. A comparative cross-sectional study was conducted on 371 (112 ART-naive group and 259 on ART) HIV positive individuals. Stool specimens were collected...

  18. Antithyroid microsomal antibody

    Science.gov (United States)

    Thyroid antimicrosomal antibody; Antimicrosomal antibody; Microsomal antibody; Thyroid peroxidase antibody; TPOAb ... Granulomatous thyroiditis Hashimoto thyroiditis High levels of these antibodies have also been linked with an increased risk ...

  19. Efficacy of tofacitinib monotherapy in methotrexate-naive patients with early or established rheumatoid arthritis

    OpenAIRE

    Fleischmann, Roy M; Huizinga, Tom W J; Kavanaugh, Arthur F; Wilkinson, Bethanie; Kwok, Kenneth; DeMasi, Ryan; van Vollenhoven, Ronald F

    2016-01-01

    Introduction Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA). Tofacitinib monotherapy was previously shown to inhibit structural damage, reduce clinical signs and symptoms of RA, and improve physical functioning over 24?months in methotrexate (MTX)-naive adult patients with RA. In this post hoc analysis, we compared efficacy and safety of tofacitinib in patients with early (disease duration

  20. Detection of Dengue Virus in Bat Flies (Diptera: Streblidae) of Common Vampire Bats, Desmodus rotundus, in Progreso, Hidalgo, Mexico.

    Science.gov (United States)

    Abundes-Gallegos, Judith; Salas-Rojas, Monica; Galvez-Romero, Guillermo; Perea-Martínez, Leonardo; Obregón-Morales, Cirani Y; Morales-Malacara, Juan B; Chomel, Bruno B; Stuckey, Matthew J; Moreno-Sandoval, Hayde; García-Baltazar, Anahi; Nogueda-Torres, Benjamin; Zuñiga, Gerardo; Aguilar-Setién, Alvaro

    2018-01-01

    Blood-feeding arthropods play a major role in the transmission of several flaviviruses, which represent an important problem for human health. Currently, dengue is one of the most important arboviral emerging diseases worldwide. Furthermore, some previous studies have reported the presence of viral nucleic acids and antibodies against dengue virus (DENV) in wild animals. Our knowledge of the role played by wildlife reservoirs in the sylvatic transmission and maintenance of DENV remains limited. Our objective was to screen blood-feeding ectoparasites (bat flies) and their common vampire bat (Desmodus rotundus) hosts, for flaviviruses in Hidalgo, Mexico. We detected Flavivirus sequences in 38 pools of ectoparasites (Diptera: Streblidae, Strebla wiedemanni and Trichobius parasiticus) and 8 tissue samples of D. rotundus by RT-PCR and semi-nested PCR using FlaviPF1S, FlaviPR2bis, and FlaviPF3S primers specific for NS5, a gene highly conserved among flaviviruses. Phylogenetic inference analysis performed using the maximum likelihood algorithm implemented in PhyML showed that six sequences clustered with DENV (bootstrap value = 53.5%). Although this study supports other reports of DENV detection in bats and arthropods other than Aedes mosquitoes, the role of these ectoparasitic flies and of hematophagous bats in the epidemiology of DENV still warrants further investigation.

  1. Antiprothrombin Antibodies

    Directory of Open Access Journals (Sweden)

    Polona Žigon

    2015-05-01

    Full Text Available In patients with the antiphospholipid syndrome (APS, the presence of a group of pathogenic autoantibodies called antiphospholipid antibodies causes thrombosis and pregnancy complications. The most frequent antigenic target of antiphospholipid antibodies are phospholipid bound β2-glycoprotein 1 (β2GPI and prothrombin. The international classification criteria for APS connect the occurrence of thrombosis and/or obstetric complications together with the persistence of lupus anticoagulant, anti-cardiolipin antibodies (aCL and antibodies against β2GPI (anti-β2GPI into APS. Current trends for the diagnostic evaluation of APS patients propose determination of multiple antiphospholipid antibodies, among them also anti-prothrombin antibodies, to gain a common score which estimates the risk for thrombosis in APS patients. Antiprothrombin antibodies are common in APS patients and are sometimes the only antiphospholipid antibodies being elevated. Methods for their determination differ and have not yet been standardized. Many novel studies confirmed method using phosphatidylserine/prothrombin (aPS/PT ELISA as an antigen on solid phase encompass higher diagnostic accuracy compared to method using prothrombin alone (aPT ELISA. Our research group developed an in-house aPS/PT ELISA with increased analytical sensitivity which enables the determination of all clinically relevant antiprothrombin antibodies. aPS/PT exhibited the highest percentage of lupus anticoagulant activity compared to aCL and anti-β2GPI. aPS/PT antibodies measured with the in-house method associated with venous thrombosis and presented the strongest independent risk factor for the presence of obstetric complications among all tested antiphospholipid antibodies

  2. Magnetic resonance imaging-guided biopsies may improve diagnosis in biopsy-naive men with suspicion of prostate cancer

    DEFF Research Database (Denmark)

    Winther, Mads Dochedahl; Balslev, Ingegerd; Boesen, Lars

    2017-01-01

    INTRODUCTION: The purpose of this pilot study was to investigate whether a short prostate biparametric magnetic resonance imaging (bp-MRI) protocol provides a valuable diagnostic addition for biopsy guidance in biopsy-naive men with a suspicion of prostate cancer (PCa). METHODS: A total of 62...... biopsy-naive patients referred to a systematic transrectal ultrasound biopsy (TRUS-bx) due to suspicion of PCa were prospectively enrolled. Bp-MRI was performed before biopsy. All lesions were scored according to the modified Prostate Imaging Reporting and Data System (PI-RADS) version 2. All patients...... underwent TRUS-bx followed by bp-MRI-guided biopsies (bp-MRI-bx) under MRI/TRUS image fusion from any bp-MRI suspicious lesions not obviously targeted by TRUS-bx. RESULTS: PCa was found in 42 (68%) and 32 (52%) patients by TRUS-bx and bp-MRI-bx, respectively. Bp-MRI-bx de-tected PCa in one patient who had...

  3. Baseline and cognition activated regional cerebral brain flow of naive paranoid schizophrenics

    International Nuclear Information System (INIS)

    Li Huafang; Gu Niufan; Xiu Yan; Chen Shaoliang

    2002-01-01

    Objective: To investigate the baseline and cognition activated regional cerebral blood flow (rCBF) in naive paranoid schizophrenics and the relationships between the symptoms and rCBF. Methods: The scale of positive and negative syndrome scale (PANSS) was adopted to evaluate the symptoms of schizophrenia. The baseline and cognition activated 99 Tc m -ethylcysteinate dimmer (ECD) SPECT were performed one after the other within two days. Wisconsin card sorting test (WCST) was used as cognitive task. Semi-quantitative analyses were applied. Results: There were no significant differences of WCST results between two groups. Compared with normal controls, the baseline rCBF ratios of left to right interior posterior temporal cortex in patients were significantly higher, while that of left mid-medial frontal cortex was significantly lower in patients. There was no significant difference of rCBF ratios of baseline to cognition activated states in patients. WCST couldn't activate the frontal function in patients. The total score of PANSS, score of positive subscale and general syndrome subscale were correlated with the rCBF ratio of several regions of interest (ROIs) . Some symptoms were correlated with the rCBF ratio of some ROIs. Conclusions: The hyperperfusion of left and right temporal inferior posterior cortex and hypoperfusion of left mid-medial frontal cortex could be seen in naive paranoid schizophrenics. Hypofrontality existed in patients before treatment. Some positive symptoms were correlated with the rCBF of some ROI

  4. Predicting ecstasy use among young people at risk: a prospective study of initially ecstasy-naive subjects

    NARCIS (Netherlands)

    Vervaeke, Hylke K. E.; Benschop, Annemieke; van den Brink, Wim; Korf, Dirk J.

    2008-01-01

    Our aim is to identify predictors of first-time ecstasy use in a prospective study among young people at risk. As part of the multidisciplinary Netherlands XTC Toxicity Study (NeXT), we monitored 188 subjects aged > or = 18 who were ecstasy-naive at baseline but seemed likely to start taking ecstasy

  5. Content Abstract Classification Using Naive Bayes

    Science.gov (United States)

    Latif, Syukriyanto; Suwardoyo, Untung; Aldrin Wihelmus Sanadi, Edwin

    2018-03-01

    This study aims to classify abstract content based on the use of the highest number of words in an abstract content of the English language journals. This research uses a system of text mining technology that extracts text data to search information from a set of documents. Abstract content of 120 data downloaded at www.computer.org. Data grouping consists of three categories: DM (Data Mining), ITS (Intelligent Transport System) and MM (Multimedia). Systems built using naive bayes algorithms to classify abstract journals and feature selection processes using term weighting to give weight to each word. Dimensional reduction techniques to reduce the dimensions of word counts rarely appear in each document based on dimensional reduction test parameters of 10% -90% of 5.344 words. The performance of the classification system is tested by using the Confusion Matrix based on comparative test data and test data. The results showed that the best classification results were obtained during the 75% training data test and 25% test data from the total data. Accuracy rates for categories of DM, ITS and MM were 100%, 100%, 86%. respectively with dimension reduction parameters of 30% and the value of learning rate between 0.1-0.5.

  6. Serum from CBA/Ca mice vaccinated with irradiated cercariae of Schistosoma mansoni protects naive recipients through the recruitment of cutaneous effector cells

    International Nuclear Information System (INIS)

    McLaren, D.J.; Smithers, S.R.

    1988-01-01

    Passive transfer experiments showed that 76% of the resistance induced in CBA/Ca mice by exposure to radiation-attenuated cercariae of Schistosoma mansoni could be transferred to naive recipients by administration of donor serum. The serum was twice as effective when given to the recipients at the time of cercarial challenge as compared to administration 5 days after challenge, a result which indicates that serum-dependent challenge elimination is probably accomplished in the cutaneous tissues. This view was confirmed by the observation that passive protection could be ablated by administration of a monoclonal antibody which depletes the cutaneous inflammatory reaction to cercarial penetration. Histopathological studies revealed that vaccine serum induced subdermal inflammatory reactions in challenged recipient mice which were identical both in duration and kinetics to those seen in conventionally vaccinated individuals. Challenge larvae, which had transformed from skin-stage to lung-stage parasites, became trapped within such reactions and eventually showed generalized vacuolation consistent with the onset of damage. Some foci were seen to contain degenerated leucocytes, free eosinophil granules and debris which is thought to represent the remnants of dead parasites. These data show that serum-transferred resistance in the vaccinated CBA/Ca mouse model involves the induction of a cutaneous inflammatory response in the recipients. (author)

  7. Klasifikasi Teks Bahasa Bali dengan Metode Information Gain dan Naive Bayes Classifier

    Directory of Open Access Journals (Sweden)

    Ida Bagus Gede Widnyana Putra

    2016-11-01

    Full Text Available Ketersediaan dokumen teks bahasa Bali yang meningkat jumlahnya membuat proses pencarian informasi pada dokumen teks berbahasa Bali menjadi semakin sulit. Mengklasifikasikanya secara manual menjadi tidak efisien mengingat peningkatan jumlah dokumen yang semakin banyak. Pada penelitian ini dikembangkan sebuah aplikasi yang dapat mengklasifikasikan teks bahasa Bali ke dalam kategori yang ditentukan. Aplikasi ini menggunakan metode klasifikasi Naive Bayes Classifier (NBC dan metode Information Gain(IG untuk seleksi fitur. Aplikasi ini diuji dengan teknik cross validation. Hasilnya adalah nilai rata-rata akurasi dari 10 fold cross validation sebesar  95,22%.

  8. The role of antibody affinity and titre in immunity to Schistosoma mansoni following vaccination with highly irradiated cercariae

    International Nuclear Information System (INIS)

    Vignali, D.A.A.; Devey, M.E.; Bickle, Q.D.; Taylor, M.G.

    1990-01-01

    Sera from rabbits and rats vaccinated with highly irradiated cercariae of Schistosoma mansoni (VRabS, VRatS) were found to be of substantially higher affinity than sera from CBA mice vaccinated four times (4 x CVMS), single sex sera (SSS) or chronic infection sera (CIS). In contrast, immunoprecipitation studies demonstrated that sera from vaccinated LA mice (LVMS) recognized 125 I-labelled schistosomular surface antigens more intensely than sera from vaccinated HA mice (HVMS). However, peritoneal macrophages from HA and LA mice in the presence of HVMS, LVMS or 4 x CVMS, and naive macrophages activated in vitro with interferon-gamma (IFN-γ)/lipopolysaccharide (LPS) mediated comparable levels of schistosomula killing in vitro. The experiments described here provide evidence that the titre of antibody rather than its affinity may be a more critical factor in the development of optimal immunity to S. mansoni. (author)

  9. Human antibody technology and the development of antibodies against cytomegalovirus.

    Science.gov (United States)

    Ohlin, Mats; Söderberg-Nauclér, Cecilia

    2015-10-01

    Cytomegalovirus (CMV) is a virus that causes chronic infections in a large set of the population. It may cause severe disease in immunocompromised individuals, is linked to immunosenescence and implied to play an important role in the pathogenesis of cardiovascular diseases and cancer. Modulation of the immune system's abilities to manage the virus represent a highly viable therapeutic option and passive immunotherapy with polyclonal antibody preparations is already in clinical use. Defined monoclonal antibodies offer many advantages over polyclonal antibodies purified from serum. Human CMV-specific monoclonal antibodies have consequently been thoroughly investigated with respect to their potential in the treatment of diseases caused by CMV. Recent advances in human antibody technology have substantially expanded the breadth of antibodies for such applications. This review summarizes the fundamental basis for treating CMV disease by use of antibodies, the basic technologies to be used to develop such antibodies, and relevant human antibody specificities available to target this virus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. 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. ...

  11. Naive Bayes-Guided Bat Algorithm for Feature Selection

    Directory of Open Access Journals (Sweden)

    Ahmed Majid Taha

    2013-01-01

    Full Text Available When the amount of data and information is said to double in every 20 months or so, feature selection has become highly important and beneficial. Further improvements in feature selection will positively affect a wide array of applications in fields such as pattern recognition, machine learning, or signal processing. Bio-inspired method called Bat Algorithm hybridized with a Naive Bayes classifier has been presented in this work. The performance of the proposed feature selection algorithm was investigated using twelve benchmark datasets from different domains and was compared to three other well-known feature selection algorithms. Discussion focused on four perspectives: number of features, classification accuracy, stability, and feature generalization. The results showed that BANB significantly outperformed other algorithms in selecting lower number of features, hence removing irrelevant, redundant, or noisy features while maintaining the classification accuracy. BANB is also proven to be more stable than other methods and is capable of producing more general feature subsets.

  12. Naive Bayes-Guided Bat Algorithm for Feature Selection

    Science.gov (United States)

    Taha, Ahmed Majid; Mustapha, Aida; Chen, Soong-Der

    2013-01-01

    When the amount of data and information is said to double in every 20 months or so, feature selection has become highly important and beneficial. Further improvements in feature selection will positively affect a wide array of applications in fields such as pattern recognition, machine learning, or signal processing. Bio-inspired method called Bat Algorithm hybridized with a Naive Bayes classifier has been presented in this work. The performance of the proposed feature selection algorithm was investigated using twelve benchmark datasets from different domains and was compared to three other well-known feature selection algorithms. Discussion focused on four perspectives: number of features, classification accuracy, stability, and feature generalization. The results showed that BANB significantly outperformed other algorithms in selecting lower number of features, hence removing irrelevant, redundant, or noisy features while maintaining the classification accuracy. BANB is also proven to be more stable than other methods and is capable of producing more general feature subsets. PMID:24396295

  13. A conformational switch high-throughput screening assay and allosteric inhibition of the flavivirus NS2B-NS3 protease.

    Directory of Open Access Journals (Sweden)

    Matthew Brecher

    2017-05-01

    Full Text Available The flavivirus genome encodes a single polyprotein precursor requiring multiple cleavages by host and viral proteases in order to produce the individual proteins that constitute an infectious virion. Previous studies have revealed that the NS2B cofactor of the viral NS2B-NS3 heterocomplex protease displays a conformational dynamic between active and inactive states. Here, we developed a conformational switch assay based on split luciferase complementation (SLC to monitor the conformational change of NS2B and to characterize candidate allosteric inhibitors. Binding of an active-site inhibitor to the protease resulted in a conformational change of NS2B and led to significant SLC enhancement. Mutagenesis of key residues at an allosteric site abolished this induced conformational change and SLC enhancement. We also performed a virtual screen of NCI library compounds to identify allosteric inhibitors, followed by in vitro biochemical screening of the resultant candidates. Only three of these compounds, NSC135618, 260594, and 146771, significantly inhibited the protease of Dengue virus 2 (DENV2 in vitro, with IC50 values of 1.8 μM, 11.4 μM, and 4.8 μM, respectively. Among the three compounds, only NSC135618 significantly suppressed the SLC enhancement triggered by binding of active-site inhibitor in a dose-dependent manner, indicating that it inhibits the conformational change of NS2B. Results from virus titer reduction assays revealed that NSC135618 is a broad spectrum flavivirus protease inhibitor, and can significantly reduce titers of DENV2, Zika virus (ZIKV, West Nile virus (WNV, and Yellow fever virus (YFV on A549 cells in vivo, with EC50 values in low micromolar range. In contrast, the cytotoxicity of NSC135618 is only moderate with CC50 of 48.8 μM on A549 cells. Moreover, NSC135618 inhibited ZIKV in human placental and neural progenitor cells relevant to ZIKV pathogenesis. Results from binding, kinetics, Western blot, mass spectrometry and

  14. Purification of immunoreactive radiolabeled moniclonal antibodies with anti-iodiotypic moniclonal antibodies

    International Nuclear Information System (INIS)

    Temponi, M.; Pupa, S.; Ferrone, S.

    1990-01-01

    A method is described to purify immunoreactive moniclonal antibodies from radiolabeled monoclonal antibody preparations. The method is based on incubation of radiolabeled monoclonal antibodies with insolubilized anti-idiotypic monoclonal antibodies to idiotopes within the antigen-combining site of monoclonal antibodies to be purified an elution of bound monoclonal antibodies with a low pH buffer. The immunoreactive fraction of the purified monoclonal antibodies was at least 82%; the yeald was at least 73%. The purification procedure did not cause any detectable change in the affinity constant of the eluted monoclonal antibodies. The method is simple and rapid; the requirement for anti-idiotypic monoclonal antibodies to idiotopes within the antigen-combining site of the antibodies to be purified is not likely to represent a major limitation in the broad application of the present method, since the hybridoma technology has greatly facilitated the development of anti-idiotypic monoclonal antibodies. (author). 12 refs.; 4 figs.; 1 tab

  15. Predicting ecstasy use among young people at risk: a prospective study of initially ecstasy-naive subjects

    NARCIS (Netherlands)

    Vervaeke, H.K.E.; Benschop, A.; van den Brink, W.; Korf, D.J.

    2008-01-01

    Our aim is to identify predictors of first-time ecstasy use in a prospective study among young people at risk. As part of the multidisciplinary Netherlands XTC Toxicity Study (NeXT), we monitored 188 subjects aged ≥ 18 who were ecstasy-naive at baseline but seemed likely to start taking ecstasy in

  16. Antibody mimetics: promising complementary agents to animal-sourced antibodies.

    Science.gov (United States)

    Baloch, Abdul Rasheed; Baloch, Abdul Wahid; Sutton, Brian J; Zhang, Xiaoying

    2016-01-01

    Despite their wide use as therapeutic, diagnostic and detection agents, the limitations of polyclonal and monoclonal antibodies have inspired scientists to design the next generation biomedical agents, so-called antibody mimetics that offer many advantages over conventional antibodies. Antibody mimetics can be constructed by protein-directed evolution or fusion of complementarity-determining regions through intervening framework regions. Substantial progress in exploiting human, butterfly (Pieris brassicae) and bacterial systems to design and select mimetics using display technologies has been made in the past 10 years, and one of these mimetics [Kalbitor® (Dyax)] has made its way to market. Many challenges lie ahead to develop mimetics for various biomedical applications, especially those for which conventional antibodies are ineffective, and this review describes the current characteristics, construction and applications of antibody mimetics compared to animal-sourced antibodies. The possible limitations of mimetics and future perspectives are also discussed.

  17. Immobilization of antibodies and enzyme-labeled antibodies by radiation polymerization

    International Nuclear Information System (INIS)

    Kumakura, M.; Kaetsu, I.; Suzuki, M.; Adachi, S.

    1983-01-01

    Immobilization of antibodies and enzyme-labeled antibodies by radiation polymerization at low temperatures was studied. The antibody activity of antibody was not affected by irradiation at an irradiation dose of below 8 MR and low temperatures. Immobilization of peroxidase-labeled anti-rabbit IgG goat IgG, anti-peroxidase, peroxidase, and anti-alpha-fetoprotein was carried out with hydrophilic and hydrophobic monomers. The activity of the immobilized enzyme-labeled antibody membranes varied with the thickness of the membranes and increased with decreasing membrane thickness. The activity of the immobilized antibody particles was varied by particle size. Immobilized anti-alpha-fetoprotein particles and membranes can be used for the assay of alpha-fetoprotein by the antigen-antibody reaction, such as a solid-phase sandwich method with high sensitivity

  18. [VGKC-complex antibodies].

    Science.gov (United States)

    Watanabe, Osamu

    2013-04-01

    Various antibodies are associated with voltage-gated potassium channels (VGKCs). Representative antibodies to VGKCs were first identified by radioimmunoassays using radioisotope-labeled alpha-dendrotoxin-VGKCs solubilized from rabbit brain. These antibodies were detected only in a proportion of patients with acquired neuromyotonia (Isaacs' syndrome). VGKC antibodies were also detected in patients with Morvan's syndrome and in those with a form of autoimmune limbic encephalitis. Recent studies indicated that the "VGKC" antibodies are mainly directed toward associated proteins (for example LGI-1 and CASPR-2) that complex with the VGKCs themselves. The "VGKC" antibodies are now commonly known as VGKC-complex antibodies. In general, LGI-1 antibodies are most commonly detected in patients with limbic encephalitis with syndrome of inappropriate secretion of antidiuretic hormone. CASPR-2 antibodies are present in the majority of patients with Morvan's syndrome. These patients develop combinations of CNS symptoms, autonomic dysfunction, and peripheral nerve hyperexcitability. Furthermore, VGKC-complex antibodies are tightly associated with chronic idiopathic pain. Hyperexcitability of nociceptive pathways has also been implicated. These antibodies may be detected in sera of some patients with neurodegenerative diseases (for example, amyotrophic lateral sclerosis and Creutzfeldt-Jakob disease).

  19. Increased functional connectivity strength of right inferior temporal gyrus in first-episode, drug-naive somatization disorder.

    Science.gov (United States)

    Su, Qinji; Yao, Dapeng; Jiang, Muliang; Liu, Feng; Jiang, Jiajing; Xu, Chunxing; Dai, Yi; Yu, Miaoyu; Long, Liling; Li, Hongzheng; Liu, Jianrong; Zhang, Zhikun; Zhang, Jian; Xiao, Changqing; Guo, Wenbin

    2015-01-01

    Evidence of brain structural and functional alterations have been implicated in patients with somatization disorder (SD). However, little is known about brain functional connectivity in SD. In the present study, resting-state functional magnetic resonance imaging (fMRI) and graph theory were used to obtain a comprehensive view of whole-brain functional connectivity and to investigate the changes of voxel-wise functional networks in patients with SD. Twenty-five first-episode, medication-naive patients with SD and 28 age-, sex- and education-matched healthy controls (HCs) underwent resting-state fMRI. The graph theory approach was employed to analyze the data. Compared to the HCs, patients with SD showed significantly increased functional connectivity strength in the right inferior temporal gyrus (ITG). There is a significant positive correlation between the z-values of the cluster in the right ITG and Hamilton Anxiety Scale scores. Our findings indicate that there is a disruption of the functional connectivity pattern in the right ITG in first-episode, treatment-naive patients with SD, which bears clinical significance. © The Royal Australian and New Zealand College of Psychiatrists 2014.

  20. Elevated glutamine/glutamate ratio in cerebrospinal fluid of first episode and drug naive schizophrenic patients

    Directory of Open Access Journals (Sweden)

    Lindström Leif H

    2005-01-01

    Full Text Available Abstract Background Recent magnetic resonance spectroscopy (MRS studies report that glutamine is altered in the brains of schizophrenic patients. There were also conflicting findings on glutamate in cerebrospinal fluid (CSF of schizophrenic patients, and absent for glutamine. This study aims to clarify the question of glutamine and glutamate in CSF of first episode and drug naive schizophrenic patients. Method Levels of glutamine and glutamate in CSF of 25 first episode and drug-naive male schizophrenic patients and 17 age-matched male healthy controls were measured by a high performance liquid chromatography. Results The ratio (126.1 (median, 117.7 ± 27.4 (mean ± S.D. of glutamine to glutamate in the CSF of patients was significantly (z = -3.29, p = 0.001 higher than that (81.01 (median, 89.1 ± 22.5 (mean ± S.D. of normal controls although each level of glutamine and glutamate in patients was not different from that of normal controls. Conclusion Our data suggests that a disfunction in glutamate-glutamine cycle in the brain may play a role in the pathophysiology of schizophrenia.

  1. Daclatasvir plus peginterferon alfa and ribavirin for treatment-naive chronic hepatitis C genotype 1 or 4 infection

    DEFF Research Database (Denmark)

    Hézode, Christophe; Hirschfield, Gideon M; Ghesquiere, Wayne

    2015-01-01

    OBJECTIVE: To evaluate the safety and efficacy of daclatasvir, an HCV NS5A inhibitor with pangenotypic activity, administered with peginterferon-alfa-2a/ribavirin. DESIGN: In this Phase 2b double-blind, placebo-controlled study, treatment-naive adults with HCV genotype 1 (N=365) or 4 (N=30...

  2. Compositions, antibodies, asthma diagnosis methods, and methods for preparing antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hongjun; Zangar, Richard C.

    2017-01-17

    Methods for preparing an antibody are provided with the method including incorporating 3-bromo-4-hydroxy-benzoic acid into a protein to form an antigen, immunizing a mammalian host with the antigen, and recovering an antibody having an affinity for the antigen from the host. Antibodies having a binding affinity for a monohalotyrosine are provided as well as composition comprising an antibody bound with monohalotyrosine. Compositions comprising a protein having a 3-bromo-4-hydroxy-benzoic acid moiety are also provided. Methods for evaluating the severity of asthma are provide with the methods including analyzing sputum of a patient using an antibody having a binding affinity for monohalotyrosine, and measuring the amount of antibody bound to protein. Methods for determining eosinophil activity in bodily fluid are also provided with the methods including exposing bodily fluid to an antibody having a binding affinity for monohalotyrosine, and measuring the amount of bound antibody to determine the eosinophil activity.

  3. Antibody Engineering and Therapeutics

    Science.gov (United States)

    Almagro, Juan Carlos; Gilliland, Gary L; Breden, Felix; Scott, Jamie K; Sok, Devin; Pauthner, Matthias; Reichert, Janice M; Helguera, Gustavo; Andrabi, Raiees; Mabry, Robert; Bléry, Mathieu; Voss, James E; Laurén, Juha; Abuqayyas, Lubna; Barghorn, Stefan; Ben-Jacob, Eshel; Crowe, James E; Huston, James S; Johnston, Stephen Albert; Krauland, Eric; Lund-Johansen, Fridtjof; Marasco, Wayne A; Parren, Paul WHI; Xu, Kai Y

    2014-01-01

    The 24th Antibody Engineering & Therapeutics meeting brought together a broad range of participants who were updated on the latest advances in antibody research and development. Organized by IBC Life Sciences, the gathering is the annual meeting of The Antibody Society, which serves as the scientific sponsor. Preconference workshops on 3D modeling and delineation of clonal lineages were featured, and the conference included sessions on a wide variety of topics relevant to researchers, including systems biology; antibody deep sequencing and repertoires; the effects of antibody gene variation and usage on antibody response; directed evolution; knowledge-based design; antibodies in a complex environment; polyreactive antibodies and polyspecificity; the interface between antibody therapy and cellular immunity in cancer; antibodies in cardiometabolic medicine; antibody pharmacokinetics, distribution and off-target toxicity; optimizing antibody formats for immunotherapy; polyclonals, oligoclonals and bispecifics; antibody discovery platforms; and antibody-drug conjugates. PMID:24589717

  4. Prediction of antibody persistency from antibody titres to natalizumab

    DEFF Research Database (Denmark)

    Jensen, Poul Erik H; Koch-Henriksen, Nils; Sellebjerg, Finn

    2012-01-01

    In a subgroup of patients with multiple sclerosis natalizumab therapy causes generation of anti-natalizumab antibodies that may be transient or persistent. It is recommended to discontinue natalizumab therapy in persistently antibody-positive patients.......In a subgroup of patients with multiple sclerosis natalizumab therapy causes generation of anti-natalizumab antibodies that may be transient or persistent. It is recommended to discontinue natalizumab therapy in persistently antibody-positive patients....

  5. High level of APOBEC3F/3G editing in HIV-2 DNA vif and pol sequences from antiretroviral-naive patients.

    Science.gov (United States)

    Bertine, Mélanie; Charpentier, Charlotte; Visseaux, Benoit; Storto, Alexandre; Collin, Gilles; Larrouy, Lucile; Damond, Florence; Matheron, Sophie; Brun-Vézinet, Françoise; Descamps, Diane

    2015-04-24

    In HIV-1, hypermutation introduced by APOBEC3F/3G cytidine deaminase activity leads to defective viruses. In-vivo impact of APOBEC3F/3G editing on HIV-2 sequences remains unknown. The objective of this study was to assess the level of APOBEC3F/3G editing in HIV-2-infected antiretroviral-naive patients. Direct sequencing of vif and pol regions was performed on HIV-2 proviral DNA from antiretroviral-naive patients included in the French Agence Nationale de Recherches sur le SIDA et les hépatites virales CO5 HIV-2 cohort. Hypermutated sequences were identified using Hypermut2.0 program. HIV-1 proviral sequences from Genbank were also assessed. Among 82 antiretroviral-naive HIV-2-infected patients assessed, 15 (28.8%) and five (16.7%) displayed Vif proviral defective sequences in HIV-2 groups A and B, respectively. A lower proportion of defective sequences was observed in protease-reverse transcriptase region. A higher median number of G-to-A mutations was observed in HIV-2 group B than in group A, both in Vif and protease-reverse transcriptase regions (P = 0.02 and P = 0.006, respectively). Compared with HIV-1 Vif sequences, a higher number of Vif defective sequences was observed in HIV-2 group A (P = 0.00001) and group B sequences (P = 0.013). We showed for the first time a high level of APOBEC3F/3G editing in HIV-2 sequences from antiretroviral-naive patients. Our study reported a group effect with a significantly higher level of APOBEC3F/3G editing in HIV-2 group B than in group A sequences.

  6. No change of dopamine transporter density in basal ganglia after risperidone treatment in drug-naive children with Tourette's disorder

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, W. K.; Ryu, Y. H.; Yoon, M. J.; Chun, K. A.; Lee, J. D. [College of Medicine, Univ. of Yonsei, Seoul (Korea, Republic of); Zee, D. Y. [Univ. of Inhwa, Incheon (Korea, Republic of); Choi, T. H. [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    2003-07-01

    Tourette's disorder (TD), which is characterized by multiple waxing and waning motor tics and one or more vocal tics, is known to be associated with abnormalities in the dopaminergic system. To testify our hypothesis that risperidone would improve tic symptoms of TD patients through the change of the dopaminergic system, we measured the DAT densities between drug-naive children with TD and normal children investigated the DAT density before and after treatment with risperidone in drug-naive children with TD, using lodine-123 labelled N-(3-iodopropen-2-yl)-2beta-carbomethoxy-3beta-(4-chlorophenyl) tropane(I-123 IPT) single photon emission computed tomography (SPECT). I-123 IPT SPECT imaging and Yale Global Tic Severity Scale-Korean version (YGTSS-K) for assessing the tic symptom severity were carried out before and after treatment with risperidone for 8 weeks in eight drug-naive children with TD. Eight normal children also underwent SPECT imaging 2 hours after an intravenous administration of I-123 IPT and carried out both quantitative and qualitative analyses using the obtained SPECT data, which were reconstructed for the assessment of the specific/non-specific DAT binding ratio in the basal ganglia. The drug-naive children with TD had a significantly greater increase in the specific/nonspecific DAT binding ratio of both basal ganglia compared with the normal children. However, no significant difference in the specific/nonspecific DAT binding ratio of the basal ganglia before and after treatment with riperidone in children with TD was not found, although tic symptoms were significantly improved with risperidone. These findings suggest that DAT densities are directly associated with the pathophysiology of TD, however, that the effect of risperidone on tic symptoms in children with TD is not attributed to the change of dopaminergic system.

  7. Differences in Expansion Potential of Naive Chimeric Antigen Receptor T Cells from Healthy Donors and Untreated Chronic Lymphocytic Leukemia Patients

    Directory of Open Access Journals (Sweden)

    Jean-Marc Hoffmann

    2018-01-01

    Full Text Available IntroductionTherapy with chimeric antigen receptor T (CART cells for hematological malignancies has shown promising results. Effectiveness of CART cells may depend on the ratio of naive (TN vs. effector (TE T cells, TN cells being responsible for an enduring antitumor activity through maturation. Therefore, we investigated factors influencing the TN/TE ratio of CART cells.Materials and methodsCART cells were generated upon transduction of peripheral blood mononuclear cells with a CD19.CAR-CD28-CD137zeta third generation retroviral vector under two different stimulating culture conditions: anti-CD3/anti-CD28 antibodies adding either interleukin (IL-7/IL-15 or IL-2. CART cells were maintained in culture for 20 days. We evaluated 24 healthy donors (HDs and 11 patients with chronic lymphocytic leukemia (CLL for the composition of cell subsets and produced CART cells. Phenotype and functionality were tested using flow cytometry and chromium release assays.ResultsIL-7/IL-15 preferentially induced differentiation into TN, stem cell memory (TSCM: naive CD27+ CD95+, CD4+ and CXCR3+ CART cells, while IL-2 increased effector memory (TEM, CD56+ and CD4+ T regulatory (TReg CART cells. The net amplification of different CART subpopulations derived from HDs and untreated CLL patients was compared. Particularly the expansion of CD4+ CARTN cells differed significantly between the two groups. For HDs, this subtype expanded >60-fold, whereas CD4+ CARTN cells of untreated CLL patients expanded less than 10-fold. Expression of exhaustion marker programmed cell death 1 on CARTN cells on day 10 of culture was significantly higher in patient samples compared to HD samples. As the percentage of malignant B cells was expectedly higher within patient samples, an excessive amount of B cells during culture could account for the reduced expansion potential of CARTN cells in untreated CLL patients. Final TN/TE ratio stayed <0.3 despite stimulation condition for patients

  8. Infliximab plus methotrexate is superior to methotrexate alone in the treatment of psoriatic arthritis in methotrexate-naive patients: the RESPOND study.

    Science.gov (United States)

    Baranauskaite, Asta; Raffayová, Helena; Kungurov, N V; Kubanova, Anna; Venalis, Algirdas; Helmle, Laszlo; Srinivasan, Shankar; Nasonov, Evgeny; Vastesaeger, Nathan

    2012-04-01

    To compare the efficacy and safety of treatment with infliximab plus methotrexate with methotrexate alone in methotrexate-naive patients with active psoriatic arthritis (PsA). In this open-label study, patients 18 years and older with active PsA who were naive to methotrexate and not receiving disease-modifying therapy (N=115) were randomly assigned (1:1) to receive either infliximab (5 mg/kg) at weeks 0, 2, 6 and 14 plus methotrexate (15 mg/week); or methotrexate (15 mg/week) alone. The primary assessment was American College of Rheumatology (ACR) 20 response at week 16. Secondary outcome measures included psoriasis area and severity index (PASI), disease activity score in 28 joints (DAS28) and dactylitis and enthesitis assessments. At week 16, 86.3% of patients receiving infliximab plus methotrexate and 66.7% of those receiving methotrexate alone achieved an ACR20 response (palone experienced a 75% or greater improvement in PASI (palone group. Treatment with infliximab plus methotrexate in methotrexate-naive patients with active PsA demonstrated significantly greater ACR20 response rates and PASI75 improvement compared with methotrexate alone and was generally well tolerated. This trial is registered in the US National Institutes of Health clinicaltrials.gov database, identifier NCT00367237.

  9. Thyroid Antibodies

    Science.gov (United States)

    ... PF4 Antibody Hepatitis A Testing Hepatitis B Testing Hepatitis C Testing HER2/neu Herpes Testing High-sensitivity C-reactive Protein (hs-CRP) Histamine Histone Antibody HIV Antibody and HIV Antigen (p24) HIV Antiretroviral Drug Resistance Testing, Genotypic HIV Viral Load HLA Testing HLA- ...

  10. Evaluation of nevirapine and/or hydroxyurea with nucleoside reverse transcriptase inhibitors in treatment-naive HIV-1-infected subjects

    NARCIS (Netherlands)

    Blanckenberg, Daniel H.; Wood, Robin; Horban, Andrzej; Beniowski, Marek; Boron-Kaczmarska, Anna; Trocha, Hanna; Halota, Waldemar; Schmidt, Reinhold E.; Fatkenheuer, G.; Jessen, Heiko; Lange, Joep M. A.

    2004-01-01

    Objective: To examine the effect of adding nevirapine (NVP) and/or hydroxyurea (HU) to a triple nucleoside analogue reverse transcriptase inhibitor (NRTI) regimen in terms of efficacy and tolerability. Methods: HIV-1-infected, treatment-naive adults were randomized, using a factorial design, to add

  11. Impaired visual, working, and verbal memory in first-episode, drug-naive patients with major depressive disorder in a Chinese population.

    Science.gov (United States)

    Chen, Ce; Jiang, Wen-Hui; Wang, Wei; Ma, Xian-Cang; Li, Ye; Wu, Jin; Hashimoto, Kenji; Gao, Cheng-Ge

    2018-01-01

    Cognitive impairment has been observed in patients with major depressive disorder (MDD). However, it remains unclear whether the deficits in specific cognitive domains are present in first-episode, drug-naïve patients or medicated patients. In the present study, using the CogState battery (CSB) Chinese language version, we evaluated the visual, working, and verbal memory in first-episode drug-naive patients and medicated patients with MDD in a Chinese population. We measured the cognitive function in first-episode drug-naïve patients (n = 36), medicated MDD patients (n = 71), and age- and sex-matched healthy control subjects (n = 59) in a Chinese population. The CSB composite scores in both first-episode drug-naive patients and medicated patients were significantly poorer than those in the healthy control subjects. The CSB sub-scores, including visual, working, and verbal memory were also significantly poorer in both patient groups than those in the healthy control subjects. In contrast, processing speed, attention/vigilance, executive function, spatial working memory, and social cognition were no different from healthy controls, whereas the executive function was significantly better in the medicated patients than in the healthy control subjects and first-episode drug-naïve patients. These findings suggest an impairment in the visual, working, and verbal memory in first-episode, drug-naive MDD patients in a Chinese population.

  12. Radiolabeled antibody imaging

    International Nuclear Information System (INIS)

    Wahl, R.L.

    1987-01-01

    Radiolabeled antibodies, in particular monoclonal antibodies, offer the potential for the specific nuclear imaging of malignant and benign diseases in man. If this imaging potential is realized, they may also have a large role in cancer treatment. This paper reviews: (1) what monoclonal antibodies are and how they differ from polyclonal antibodies, (2) how they are produced and radiolabeled, (3) the results of preclinical and clinical trials in cancer imaging, including the utility of SPECT and antibody fragments, (4) the role of antibodies in the diagnosis of benign diseases, (5) alternate routes of antibody delivery, (6) the role of these agents in therapy, and (7) whether this technology ''revolutionizes'' the practice of nuclear radiology, or has a more limited complementary role in the imaging department

  13. Human monoclonal antibodies: the residual challenge of antibody immunogenicity.

    Science.gov (United States)

    Waldmann, Herman

    2014-01-01

    One of the major reasons for seeking human monoclonal antibodies has been to eliminate immunogenicity seen with rodent antibodies. Thus far, there has yet been no approach which absolutely abolishes that risk for cell-binding antibodies. In this short article, I draw attention to classical work which shows that monomeric immunoglobulins are intrinsically tolerogenic if they can be prevented from creating aggregates or immune complexes. Based on these classical studies two approaches for active tolerization to therapeutic antibodies are described.

  14. The role of antibody affinity and titre in immunity to Schistosoma mansoni following vaccination with highly irradiated cercariae

    Energy Technology Data Exchange (ETDEWEB)

    Vignali, D.A.A.; Devey, M.E.; Bickle, Q.D.; Taylor, M.G. (London School of Hygiene and Tropical Medicine (UK))

    1990-02-01

    Sera from rabbits and rats vaccinated with highly irradiated cercariae of Schistosoma mansoni (VRabS, VRatS) were found to be of substantially higher affinity than sera from CBA mice vaccinated four times (4 x CVMS), single sex sera (SSS) or chronic infection sera (CIS). In contrast, immunoprecipitation studies demonstrated that sera from vaccinated LA mice (LVMS) recognized {sup 125}I-labelled schistosomular surface antigens more intensely than sera from vaccinated HA mice (HVMS). However, peritoneal macrophages from HA and LA mice in the presence of HVMS, LVMS or 4 x CVMS, and naive macrophages activated in vitro with interferon-gamma (IFN-{gamma})/lipopolysaccharide (LPS) mediated comparable levels of schistosomula killing in vitro. The experiments described here provide evidence that the titre of antibody rather than its affinity may be a more critical factor in the development of optimal immunity to S. mansoni. (author).

  15. Microbials for the production of monoclonal antibodies and antibody fragments.

    Science.gov (United States)

    Spadiut, Oliver; Capone, Simona; Krainer, Florian; Glieder, Anton; Herwig, Christoph

    2014-01-01

    Monoclonal antibodies (mAbs) and antibody fragments represent the most important biopharmaceutical products today. Because full length antibodies are glycosylated, mammalian cells, which allow human-like N-glycosylation, are currently used for their production. However, mammalian cells have several drawbacks when it comes to bioprocessing and scale-up, resulting in long processing times and elevated costs. By contrast, antibody fragments, that are not glycosylated but still exhibit antigen binding properties, can be produced in microbial organisms, which are easy to manipulate and cultivate. In this review, we summarize recent advances in the expression systems, strain engineering, and production processes for the three main microbials used in antibody and antibody fragment production, namely Saccharomyces cerevisiae, Pichia pastoris, and Escherichia coli. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Predicting Ecstasy Use among Young People at Risk: A Prospective Study of Initially Ecstasy-Naive Subjects

    Science.gov (United States)

    Vervaeke, Hylke K.E.; Benschop, Annemieke; Van Den Brink, Wim; Korf, Dirk J.

    2008-01-01

    Our aim is to identify predictors of first-time ecstasy use in a prospective study among young people at risk. As part of the multidisciplinary Netherlands XTC Toxicity Study (NeXT), we monitored 188 subjects aged up to 18 years who were ecstasy-naive at baseline but seemed likely to start taking ecstasy in the near future. After an 11- to…

  17. Time to viral load suppression in antiretroviral-naive and -experienced HIV-infected pregnant women on highly active antiretroviral therapy: implications for pregnant women presenting late in gestation.

    Science.gov (United States)

    Aziz, N; Sokoloff, A; Kornak, J; Leva, N V; Mendiola, M L; Levison, J; Feakins, C; Shannon, M; Cohan, D

    2013-11-01

    To compare time to achieve viral load HIV-infected antiretroviral (ARV) -naive versus ARV-experienced pregnant women on highly active antiretroviral therapy (HAART). Retrospective cohort study. Three university medical centers, USA. HIV-infected pregnant women initiated or restarted on HAART during pregnancy. We calculated time to viral load HIV-infected pregnant women on HAART who reported at least 50% adherence, stratifying based on previous ARV exposure history. Time to HIV viral load HIV-infected pregnant women, comprising 76 ARV-naive and 62 ARV-experienced. Ninety-three percent of ARV-naive women achieved a viral load HIV log10 viral load was associated with a later time of achieving viral load HIV log10 viral load was associated with a longer time of achieving viral load Pregnant women with ≥50% adherence, whether ARV-naive or ARV-experienced, on average achieve a viral load HIV log10 viral load were all statistically significant predictors of earlier time to achieve viral load <400 copies/ml and <1000 copies/ml. Increased CD4 count was statistically significant as a predictor of earlier time to achieve viral load <1000 copies/ml. © 2013 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2013 RCOG.

  18. Enzalutamide in Men with Chemotherapy-naive Metastatic Castration-resistant Prostate Cancer: Extended Analysis of the Phase 3 PREVAIL Study

    NARCIS (Netherlands)

    Beer, T.M.; Armstrong, A.J.; Rathkopf, D.; Loriot, Y.; Sternberg, C.N.; Higano, C.S.; Iversen, P.; Evans, C.P.; Kim, C.S.; Kimura, G.; Miller, K.; Saad, F.; Bjartell, A.S.; Borre, M.; Mulders, P.; Tammela, T.L.; Parli, T.; Sari, S.; Os, S. van; Theeuwes, A.; Tombal, B.

    2017-01-01

    Enzalutamide significantly improved radiographic progression-free survival (rPFS) and overall survival (OS) among men with chemotherapy-naive metastatic castration-resistant prostate cancer at the prespecified interim analysis of PREVAIL, a phase 3, double-blind, randomized study. We evaluated the

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

    Science.gov (United States)

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

    2011-04-01

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

  20. Human Monoclonal Antibodies against West Nile Virus Induced by Natural Infection Neutralize at a Postattachment Step

    NARCIS (Netherlands)

    Vogt, Matthew R.; Moesker, Bastiaan; Goudsmit, Jaap; Jongeneelen, Mandy; Austin, S. Kyle; Oliphant, Theodore; Nelson, Steevenson; Pierson, Theodore C.; Wilschut, Jan; Throsby, Mark; Diamond, Michael S.

    West Nile virus (WNV) is a neurotropic flavivirus that is now a primary cause of epidemic encephalitis in North America. Studies of mice have demonstrated that the humoral immune response against WNV limits primary infection and protects against a secondary challenge. The most-potent neutralizing

  1. Production and characterization of human anti-V3 monoclonal antibodies from the cells of HIV-1 infected Indian donors

    Directory of Open Access Journals (Sweden)

    Andrabi Raiees

    2012-09-01

    Full Text Available Abstract Background Analysis of human monoclonal antibodies (mAbs developed from HIV-1 infected donors have enormously contributed to the identification of neutralization sensitive epitopes on the HIV-1 envelope glycoprotein. The third variable region (V3 is a crucial target on gp120, primarily due to its involvement in co-receptor (CXCR4 or CCR5 binding and presence of epitopes recognized by broadly neutralizing antibodies. Methods Thirty-three HIV-1 seropositive drug naive patients (18 males and 15 females within the age range of 20–57 years (median = 33 years were recruited in this study for mAb production. The mAbs were selected from EBV transformed cultures with conformationally constrained Cholera-toxin-B containing V3C (V3C-CTB fusion protein. We tested the mAbs for their binding with HIV-1 derived proteins and peptides by ELISA and for neutralization against HIV-1 viruses by TZM-bl assays. Results We isolated three anti-V3 mAbs, 277, 903 and 904 from the cells of different individuals. The ELISA binding revealed a subtype-C and subtype-A specific binding of antibody 277 and 903 while mAb 904 exhibited cross reactivity also with subtype-B V3. Epitope mapping of mAbs with overlapping V3 peptides showed exclusive binding to V3 crown. The antibodies displayed high and low neutralizing activity against 2/5 tier 1 and 1/6 tier 2 viruses respectively. Overall, we observed a resistance of the tier 2 viruses to neutralization by the anti-V3 mAbs, despite the exposure of the epitopes recognized by these antibodies on two representative native viruses (Du156.12 and JRFL, suggesting that the affinity of mAb might equally be crucial for neutralization, as the epitope recognition. Conclusions Our study suggests that the anti-V3 antibodies derived from subtype-C infected Indian patients display neutralization potential against tier 1 viruses while such activity may be limited against more resistant tier 2 viruses. Defining the fine epitope

  2. Monoclonal antibody

    International Nuclear Information System (INIS)

    Oyamada, Hiyoshimaru

    1987-01-01

    Some aspects of monoclonal antibodies are described, centering on studies made by the author and those presented at the Second International Conference on Monoclonal Antibody Immunoconjugates for Cancer held in March this year (1987). The history of immuno-nuclear medicine and procedures for producing monoclonal antibodies are briefly outlined. Monoclonal antibodies are immunoglobulins. Here, the structure of IgG, which is used most frequently, is described. An IgG is composed of two antigen binding fragments (Fab) and one crystallizable fragment (Fc). The end portion of a Fab reacts with an antigen. One of the major applications of immuno-nuclear medicine is the diagnosis of cancer. As label nucleides, 131 I and 111 I were selected in most cases in the past while 123 I and 99m Tc are currently used more often. Advantages and disadvantages of this diagnosis method is discussed citing studies presented at the First (1986) and Second (1987) International Conference on Monoclonal Antibody Immunoconjugates for Cancer. The present status of the application of monoclonal antibodies to treatment of cancer is also described. (Nogami, K.)

  3. Immune Antibody Libraries: Manipulating The Diverse Immune Repertoire for Antibody Discovery.

    Science.gov (United States)

    Lim, Theam Soon; Chan, Soo Khim

    2016-01-01

    Antibody phage display is highly dependent on the availability of antibody libraries. There are several forms of libraries depending mainly on the origin of the source materials. There are three major classes of libraries, mainly the naïve, immune and synthetic libraries. Immune antibody libraries are designed to isolate specific and high affinity antibodies against disease antigens. The pre-exposure of the host to an infection results in the production of a skewed population of antibodies against the particular infection. This characteristic takes advantage of the in vivo editing machinery to generate bias and specific immune repertoire. The skewed but diverse repertoire of immune libraries has been adapted successfully in the generation of antibodies against a wide range of diseases. We envisage immune antibody libraries to play a greater role in the discovery of antibodies for diseases in the near future. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  4. IL-2 Enhances Gut Homing Potential of Human Naive Regulatory T Cells Early in Life.

    Science.gov (United States)

    Hsu, Peter S; Lai, Catherine L; Hu, Mingjing; Santner-Nanan, Brigitte; Dahlstrom, Jane E; Lee, Cheng Hiang; Ajmal, Ayesha; Bullman, Amanda; Arbuckle, Susan; Al Saedi, Ahmed; Gacis, Lou; Nambiar, Reta; Williams, Andrew; Wong, Melanie; Campbell, Dianne E; Nanan, Ralph

    2018-06-15

    Recent evidence suggests early environmental factors are important for gut immune tolerance. Although the role of regulatory T (Treg) cells for gut immune homeostasis is well established, the development and tissue homing characteristics of Treg cells in children have not been studied in detail. In this article, we studied the development and homing characteristics of human peripheral blood Treg cell subsets and potential mechanisms inducing homing molecule expression in healthy children. We found contrasting patterns of circulating Treg cell gut and skin tropism, with abundant β7 integrin + Treg cells at birth and increasing cutaneous lymphocyte Ag (CLA + ) Treg cells later in life. β7 integrin + Treg cells were predominantly naive, suggesting acquisition of Treg cell gut tropism early in development. In vitro, IL-7 enhanced gut homing but reduced skin homing molecule expression in conventional T cells, whereas IL-2 induced a similar effect only in Treg cells. This effect was more pronounced in cord compared with adult blood. Our results suggest that early in life, naive Treg cells may be driven for gut tropism by their increased sensitivity to IL-2-induced β7 integrin upregulation, implicating a potential role of IL-2 in gut immune tolerance during this critical period of development. Copyright © 2018 by The American Association of Immunologists, Inc.

  5. DR3 regulation of apoptosis of naive T-lymphocytes in children with acute infectious mononucleosis.

    Science.gov (United States)

    Filatova, Elena Nikolaevna; Anisenkova, Elena Viktorovna; Presnyakova, Nataliya Borisovna; Utkin, Oleg Vladimirovich

    2016-09-01

    Acute infectious mononucleosis (AIM) is a widespread viral disease that mostly affects children. Development of AIM is accompanied by a change in the ratio of immune cells. This is provided by means of different biological processes including the regulation of apoptosis of naive T-cells. One of the potential regulators of apoptosis of T-lymphocytes is a death receptor 3 (DR3). We have studied the role of DR3 in the regulation of apoptosis of naive CD4 + (nTh) and CD8 + (nCTL) T-cells in healthy children and children with AIM. In healthy children as well as in children with AIM, the activation of DR3 is accompanied by inhibition of apoptosis of nTh. In healthy children, the stimulation of DR3 resulted in the increase in apoptosis of nCTL. On the contrary, in children with AIM, the level of apoptosis of nCTL decreased after DR3 activation, which is a positive contribution to the antiviral immune response. In children with AIM, nCTL are characterized by reduced level of apoptosis as compared with healthy children. These results indicate that DR3 can be involved in the reduction of sensitivity of nCTL to apoptosis in children with AIM.

  6. Prevalence of metabolic syndrome in HIV-infected patients naive to antiretroviral therapy or receiving a first-line treatment.

    Science.gov (United States)

    Calza, Leonardo; Colangeli, Vincenzo; Magistrelli, Eleonora; Rossi, Nicolo'; Rosselli Del Turco, Elena; Bussini, Linda; Borderi, Marco; Viale, Pierluigi

    2017-05-01

    The combination antiretroviral therapy (cART) has dramatically improved the life expectancy of patients with HIV infection, but may lead to several long-term metabolic abnormalities. However, data about the frequency of metabolic syndrome (MS) in HIV-infected people vary considerably across different observational studies. The prevalence of MS among HIV-infected patients was evaluated by a cross-sectional study conducted among subjects naive to cART or receiving the first antiretroviral regimen and referring to our Clinics from January 2015 to December 2015. The diagnosis of MS was made based on the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III), and International Diabetes Federation (IDF) criteria. The study recruited 586 patients: 98 naive to cART and 488 under the first antiretroviral treatment. The prevalence of MS, according to NCEP-ATP III criteria, was significantly higher among treated patients than among naive ones (20.9% vs. 7.1%; p = 0.014). The most frequently reported components of MS among treated patients were high triglycerides (44.3%), low high-density lipoprotein cholesterol (41.1%), and hypertension (19.7%). On multivariate analysis, long duration of HIV infection, low nadir of CD4 lymphocytes, high body mass index, current use of one protease inhibitor, and long duration of cART were significantly associated with a higher risk of MS, while current use of one integrase inhibitor was significantly associated with a lower risk of MS. The non-negligible prevalence of MS among HIV-infected patients under cART requires a careful and periodic monitoring of its components, with particular attention to dyslipidemia and hypertension.

  7. Temporal variation in viral hemorrhagic septicemia virus antibodies in freshwater drum (Aplodinotus grunniens) indicates cyclic transmission in Lake Winnebago, Wisconsin

    Science.gov (United States)

    Wilson-Rothering, Anna; Marcquenski, Susan; Koenigs, Ryan P.; Bruch, Ronald; Kamke, Kendall; Isermann, Daniel A.; Thurman, Andrew; Toohey-Kurth, Kathy; Goldberg, Tony

    2015-01-01

    Viral hemorrhagic septicemia virus (VHSV) is an emerging pathogen that causes mass mortality in multiple fish species. In 2007, the Great Lakes freshwater strain, type IVb, caused a large die-off of freshwater drum (Aplodinotus grunniens) in Lake Winnebago, Wisconsin, USA. To evaluate the persistence and transmission of VHSV, freshwater drum from Lake Winnebago were tested for antibodies to the virus using recently developed virus neutralization (VN) and enzyme-linked immunosorbent (ELISA) assays. Samples were also tested by real-time reverse transcription-PCR (rRT-PCR) to detect viral RNA. Of 548 serum samples tested, 44 (8.03%) were positive by VN (titers ranging from 1:16 to 1:1,024) and 45 (8.21%) were positive by ELISA, including 7 fish positive by both assays. Antibody prevalence increased with age and was higher in one northwestern area of Lake Winnebago than in other areas. Of 3,864 tissues sampled from 551 fish, 1 spleen and 1 kidney sample from a single adult female fish collected in the spring of 2012 tested positive for VHSV by rRT-PCR, and serum from the same fish tested positive by VN and ELISA. These results suggest that VHSV persists and viral transmission may be active in Lake Winnebago even in years following outbreaks and that wild fish may survive VHSV infection and maintain detectable antibody titers while harboring viral RNA. Influxes of immunologically naive juvenile fish through recruitment may reduce herd immunity, allow VHSV to persist, and drive superannual cycles of transmission that may sporadically manifest as fish kills.

  8. Monoclonal antibodies and cancer

    International Nuclear Information System (INIS)

    Haisma, H.J.

    1987-01-01

    The usefulness of radiolabeled monoclonal antibodies for imaging and treatment of human (ovarian) cancer was investigated. A review of tumor imaging with monoclonal antibodies is presented. Special attention is given to factors that influence the localization of the antibodies in tumors, isotope choice and methods of radiolabeling of the monoclonal antibodies. Two monoclonal antibodies, OC125 and OV-TL3, with high specificity for human epithelial ovarian cancer are characterized. A simple radio-iodination technique was developed for clinical application of the monoclonal antibodies. The behavior of monoclonal antibodies in human tumor xenograft systems and in man are described. Imaging of tumors is complicated because of high background levels of radioactivity in other sites than the tumor, especially in the bloodpool. A technique was developed to improve imaging of human tumor xenographs in nude mice, using subtraction of a specific and a non-specific antibody, radiolabeled with 111 In, 67 Ga and 131 I. To investigate the capability of the two monoclonal antibodies, to specifically localize in human ovarian carcinomas, distribution studies in mice bearing human ovarian carcinoma xenografts were performed. One of the antibodies, OC125, was used for distribution studies in ovarian cancer patients. OC125 was used because of availability and approval to use this antibody in patients. The same antibody was used to investigate the usefulness of radioimmunoimaging in ovarian cancer patients. The interaction of injected radiolabeled antibody OC125 with circulating antigen and an assay to measure the antibody response in ovarian cancer patients after injection of the antibody is described. 265 refs.; 30 figs.; 19 tabs

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

    Science.gov (United States)

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

    2011-01-01

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

  10. DARPA Antibody Technology Program. Standardized Test Bed for Antibody Characterization: Characterization of an MS2 ScFv Antibody Produced by Illumina

    Science.gov (United States)

    2016-08-01

    ECBC-TR-1395 DARPA ANTIBODY TECHNOLOGY PROGRAM STANDARDIZED TEST BED FOR... ANTIBODY CHARACTERIZATION: CHARACTERIZATION OF AN MS2 SCFV ANTIBODY PRODUCED BY ILLUMINA Patricia E. Buckley Alena M. Calm Heather Welsh Roy...4. TITLE AND SUBTITLE DARPA Antibody Technology Program Standardized Test Bed for Antibody Characterization: Characterization of an MS2 ScFv

  11. Left ventricular function at two-year follow-up in treatment-naive rheumatoid arthritis patients is associated with anti-cyclic citrullinated peptide antibody status

    DEFF Research Database (Denmark)

    Løgstrup, Brian B; Masic, D.; Laurbjerg, T. B.

    2017-01-01

    Objectives: In rheumatoid arthritis (RA), the role of autoimmunity, especially anti-cyclic citrullinated peptide antibody (anti-CCP) level, and the time-course of left ventricular (LV) function is unknown. The objective was to assess LV function and the amount of coronary calcium in relation...... assessed LV function by conventional echocardiography and speckle-tracking echocardiography. We estimated the amount and progression of coronary calcium by coronary computed tomography. Patients were examined at the time of diagnosis and after 2 years. Results: Patients with elevated anti-CCP at baseline...

  12. Hippocampal and caudate volume reductions in antipsychotic-naive first-episode schizophrenia

    DEFF Research Database (Denmark)

    Ebdrup, Bjørn Hylsebeck; Glenthøj, Birte; Rasmussen, Hans

    2010-01-01

    of a false discovery rate correction (p brain structure volumes. We grouped patients as those with (n = 9) or without (n = 29) any lifetime substance abuse to examine the possible effects of substance abuse. RESULTS: We found......BACKGROUND: Enlarged ventricles and reduced hippocampal volume are consistently found in patients with first-episode schizophrenia. Studies investigating brain structure in antipsychotic-naive patients have generally focused on the striatum. In this study, we examined whether ventricular...... healthy controls by use of a 3-T scanner. We warped the brain images to each other by use of a high-dimensional intersubject registration algorithm. We performed voxel-wise group comparisons with permutation tests. We performed small volume correction for the hippocampus, caudate and ventricles by use...

  13. Higher cytotoxicity of divalent antibody-toxins than monovalent antibody-toxins

    International Nuclear Information System (INIS)

    Won, JaeSeon; Nam, PilWon; Lee, YongChan; Choe, MuHyeon

    2009-01-01

    Recombinant antibody-toxins are constructed via the fusion of a 'carcinoma-specific' antibody fragment to a toxin. Due to the high affinity and high selectivity of the antibody fragments, antibody-toxins can bind to surface antigens on cancer cells and kill them without harming normal cells [L.H. Pai, J.K. Batra, D.J. FitzGerald, M.C. Willingham, I. Pastan, Anti-tumor activities of immunotoxins made of monoclonal antibody B3 and various forms of Pseudomonas exotoxin, Proc. Natl. Acad. Sci. USA 88 (1991) 3358-3362]. In this study, we constructed the antibody-toxin, Fab-SWn-PE38, with SWn (n = 3, 6, 9) sequences containing n-time repeated (G 4 S) between the Fab fragment and PE38 (38 kDa truncated form of Pseudomonas exotoxin A). The SWn sequence also harbored one cysteine residue that could form a disulfide bridge between two Fab-SWn-PE38 monomers. We assessed the cytotoxicity of the monovalent (Fab-SWn-PE38), and divalent ([Fab-SWn-PE38] 2 ) antibody-toxins. The cytotoxicity of the dimer against the CRL1739 cell line was approximately 18.8-fold higher than that of the monomer on the ng/ml scale, which was approximately 37.6-fold higher on the pM scale. These results strongly indicate that divalency provides higher cytotoxicity for an antibody-toxin.

  14. 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; ...

  15. Seroprevalence of West Nile Virus in feral horses on Sheldon National Wildlife Refuge, Nevada, United States

    Science.gov (United States)

    Franson, J. Christian; Hofmeister, Erik K.; Collins, Gail H.; Dusek, Robert J.

    2011-01-01

    We screened 1,397 feral horses (Equus caballus) on Sheldon National Wildlife Refuge, Nevada, United States, for IgM and IgG against flavivirus during 2004–2006, 2008, and 2009. Positive serum samples were tested for neutralizing antibodies to West Nile virus (WNV) and St. Louis encephalitis virus (SLEV). One animal was positive for antibody against WNV in 2004, but all others tested in 2004–2006 were negative. In 2008 and 2009, we found evidence of increasing seropositive horses with age, whereas seroprevalence of WNV decreased from 19% in 2008 to 7.2% in 2009. No horses were positive for antibody against SLEV. Being unvaccinated, feral horses can be useful for WNV surveillance.

  16. Anti-insulin antibody test

    Science.gov (United States)

    Insulin antibodies - serum; Insulin Ab test; Insulin resistance - insulin antibodies; Diabetes - insulin antibodies ... Normally, there are no antibodies against insulin in your blood. ... different laboratories. Some labs use different measurements or ...

  17. Fitur Seleksi Forward Selection Untuk Menetukan Atribut Yang Berpengaruh Pada Klasifikasi Kelulusan Mahasiswa Fakultas Ilmu Komputer UNAKI Semarang Menggunakan Algoritma Naive Bayes

    Directory of Open Access Journals (Sweden)

    Mohamad Fajarianditya Nugroho

    2017-09-01

    Full Text Available Data mining dalam dunia pendidikan dikenal dengan Educational Data Mining. EDM mengembangkan metode untuk menggali data pendidikan dan menggunakan metode tersebut untuk lebih memahami siswa. EDM dapat membantu pendidik untuk menganalisis cara belajar, mendeteksi mahasiswa yang memerlukan dukungan dan memprediksi kinerja mahasiswa. Perguruan tinggi perlu melakukan prediksi perilaku mahasiswa dan peringatan dini untuk mencegah secara dini kegagalan akademik mahasiswa. Naive Bayes memanfaatkan fungsi seleksi fitur dari Forward Selection untuk pemilihan atribut data dengan karakteristik data itu sendiri, dan meningkatkan ketepatan klasifikasi Naïve Bayes. Forward Selection berbasis Naive Bayes lebih akurat dan efektif dalam mengklasifikasikan status kelulusan mahasiswa dengan hasil akurasi 97,14% dan termasuk dalam kategori “excellent classification” dan memperoleh atribut yang berpengaruh yaitu: status pekerjaan dan IPK semester 4

  18. Hepatitis A virus antibody

    International Nuclear Information System (INIS)

    Novak, J.; Kselikova, M.; Urbankova, J.

    1980-01-01

    A description is presented of a radioimmunoassay designed to prove the presence of the antibody against the hepatitis A virus (HA Ab, anti-Ha) using an Abbott HAVAB set. This proof as well as the proof of the antibody against the nucleus of the hepatitis B virus is based on competition between a normal antibody against hepatitis A virus and a 125 I-labelled antibody for the binding sites of a specific antigen spread all over the surface of a tiny ball; this is then indirect proof of the antibody under investigation. The method is described of reading the results from the number of impulses per 60 seconds: the higher the titre of the antibody against the hepatitis A virus in the serum examined, the lower the activity of the specimen concerned. The rate is reported of incidence of the antibody against the hepatitis A virus in a total of 68 convalescents after hepatitis A; the antibody was found in 94.1%. The immunoglobulin made from the convalescents' plasma showed the presence of antibodies in dilutions as high as 1:250 000 while the comparable ratio for normal immunoglobulin Norga was only 1:2500. Differences are discussed in the time incidence of the antibodies against the hepatitis A virus, the antibodies against the surface antigen of hepatitis B, and the antibody against the nucleus of the hepatitis V virus. (author)

  19. A naive Bayes model for robust remaining useful life prediction of lithium-ion battery

    International Nuclear Information System (INIS)

    Ng, Selina S.Y.; Xing, Yinjiao; Tsui, Kwok L.

    2014-01-01

    Highlights: • Robustness of RUL predictions for lithium-ion batteries is analyzed quantitatively. • RUL predictions of the same battery over cycle life are evaluated. • RUL predictions of batteries over different operating conditions are evaluated. • Naive Bayes (NB) is proposed for predictions under constant discharge environments. • Its robustness and accuracy are compared with that of support vector machine (SVM). - Abstract: Online state-of-health (SoH) estimation and remaining useful life (RUL) prediction is a critical problem in battery health management. This paper studies the modeling of battery degradation under different usage conditions and ambient temperatures, which is seldom considered in the literature. Li-ion battery RUL prediction under constant operating conditions at different values of ambient temperature and discharge current are considered. A naive Bayes (NB) model is proposed for RUL prediction of batteries under different operating conditions. It is shown in this analysis that under constant discharge environments, the RUL of Li-ion batteries can be predicted with the NB method, irrespective of the exact values of the operating conditions. The case study shows that the NB generates stable and competitive prediction performance over that of the support vector machine (SVM). This also suggests that, while it is well known that the environmental conditions have big impact on the degradation trend, it is the changes in operating conditions of a Li-ion battery over cycle life that makes the Li-ion battery degradation and RUL prediction even more difficult

  20. Nuclear medicine: Monoclonal antibodies

    International Nuclear Information System (INIS)

    Endo, K.; Sakahara, H.; Koizumi, M.; Kawamura, Y.; Torizuka, K.; Yokoyama, A.

    1986-01-01

    Antitumor monoclonal antibody was successfully labeled with Tc-99m by using dithiosemicarbazone (DTS) as a bifunctional chelating agent. In the first step, DTS was coupled to antibody without loss of immunoreactivity; the compound then efficiently formed a neutral 1:1 chelate with pentavalent or tetravalent Tc-99m. Imaging with Tc-99m-labeled monoclonal antibody to human osteosarcoma (OST-7) clearly displayed a small tumor in nude mice at 6 and 24 hours after intravenous administration. The tumor-to-blood ratio of the Tc-99m-labeled monoclonal antibody was higher than that of a radioiodinated antibody and similar to that of an In-111-labeled antibody. Thus, conjugation of DTS to monoclonal antibody followed by radiometalation is a simple and efficient method of preparing Tc-99m-labeled monoclonal antibody

  1. Donor-derived HLA antibody production in patients undergoing SCT from HLA antibody-positive donors.

    Science.gov (United States)

    Taniguchi, K; Yoshihara, S; Maruya, E; Ikegame, K; Kaida, K; Hayashi, K; Kato, R; Inoue, T; Fujioka, T; Tamaki, H; Okada, M; Onuma, T; Fujii, N; Kusunoki, Y; Soma, T; Saji, H; Ogawa, H

    2012-10-01

    Pre-existing donor-specific HLA antibodies in patients undergoing HLA-mismatched SCT have increasingly been recognized as a risk factor for primary graft failure. However, the clinical implications of the presence of HLA antibodies in donors remain unknown. We prospectively examined 123 related donors for the presence of HLA antibodies by using a Luminex-based single antigen assay. Of these, 1/57 (1.8%) male, 6/27 (22%) parous female and 0/39 (0%) nonparous female donors were HLA antibody-positive. Then, we determined the presence of HLA antibodies in seven patients who received SCT from antibody-positive donors. Of these, four became HLA antibody-positive after SCT. The specificities of the antibodies that emerged in the patients closely resembled those of the antibodies found in the donors, indicating their production by donor-derived plasma cells. Moreover, the kinetics of the HLA antibody levels were similar in all four patients: levels started increasing within 1 week after SCT and peaked at days 10-21, followed by a gradual decrease. These results suggest that donor-derived HLA antibody production frequently occurs in patients undergoing SCT from antibody-positive donors. Further studies are warranted for clarifying the clinical significance of donor-derived HLA antibodies, including the role of these antibodies in post transplant platelet transfusion refractoriness.

  2. Zika virus: Vaccine initiatives and obstacles

    Directory of Open Access Journals (Sweden)

    Reema Mukherjee

    2017-01-01

    Full Text Available Over 130,000 humans in Brazil are infected with Zika virus (ZIKV since March 2015, and presently 29 countries in Americas have reported local autochthonous ZIKV transmission. Besides the associated clinical features, Brazil has also reported a temporal and spatial association of ZIKV with Guillain-Barre syndrome (GBS and Zika fetal syndrome. ZIKV vaccine approaches include purified inactivated virus, nucleic acid-based vaccines (DNA, RNA, live vector vaccines, subunit vaccines, virus-like particle technologies, and live recombinant vaccines similar to the technologies used against other human flaviviruses. At present, 15 commercial entities are involved in the development of ZIKV vaccine. Vaccines developed through different approaches would have their own inherent advantages and disadvantages. The presentation of disease in different populations and lack of clarity on the pathogenesis and complications is the most important obstacle. Second, Zika belongs to a genus that is notorious for the antibody-mediated enhancement of infection, which proved to be a stumbling block during the development of the dengue vaccine. Identifying large naive and yet uninfected at-risk populations may be an obstacle to demonstrating efficacy. Next, the association of Zika with GBS is being researched since the vaccine may have the potential to provoke similar neuropathophysiologic mechanisms. Zika's association with adverse fetal outcomes necessitates that pregnant women and women of childbearing age are considered for evaluating vaccines, which form a vulnerable group for vaccine trials.

  3. Molecular Characterization of HBV Strains Circulating among the Treatment-Naive HIV/HBV Co-Infected Patients of Eastern India

    Science.gov (United States)

    Saha, Debraj; Pal, Ananya; Biswas, Avik; Panigrahi, Rajesh; Sarkar, Neelakshi; Das, Dipanwita; Sarkar, Jayeeta; Guha, Subhasish Kamal; Saha, Bibhuti; Chakrabarti, Sekhar; Chakravarty, Runu

    2014-01-01

    Previously we reported that the exposure to hepatitis B virus (HBV) infection serves as a major threat among the treatment naive HIV infected population of eastern India. Hence, molecular characterization of these strains is of utmost importance in order to identify clinically significant HBV mutations. A total of 85 treatment naive HIV/HBV co-infected participants were included of whom the complete basal core promoter/precore region, the core and the whole envelope gene could be successfully sequenced for 59, 57 and 39 isolates respectively. Following phylogenetic analysis, it was found that HBV/D was the predominant genotype with HBV/D2 (38.5%) being the most prevalent subgenotype followed by HBV/A1. The major mutations affecting HBeAg expression includes the A1762T/G1764A (13.6%), G1896A (22%) and G1862T mutation (33.9%) which was predominantly associated with HBV/A1. Moreover, the prevalence of G1896A was considerably high among the HBeAg negative HIV/HBV co-infected subjects compared to HBV mono-infection. The main amino acid substitutions within the MHC class II restricted T-cell epitope of HBcAg includes the T12S (15.8%) and T67N (12.3%) mutation and the V27I (10.5%) mutation in the MHC class I restricted T-cell epitope. PreS1/S2 deletion was detected in 3 isolates with all harboring the BCP double mutation. Furthermore, the frequently occurring mutations in the major hydrophilic loop of the S gene include the T125M, A128V and M133I/L. Therefore, this study is the first from India to report useful information on the molecular heterogeneity of the HBV strains circulating among the treatment naive HIV/HBV co-infected population and is thus clinically relevant. PMID:24587360

  4. The Galileo Bias: A Naive Conceptual Belief That Influences People's Perceptions and Performance in a Ball-Dropping Task

    Science.gov (United States)

    Oberle, Crystal D.; McBeath, Michael K.; Madigan, Sean C.; Sugar, Thomas G.

    2005-01-01

    This research introduces a new naive physics belief, the Galileo bias, whereby people ignore air resistance and falsely believe that all objects fall at the same rate. Survey results revealed that this bias is held by many and is surprisingly strongest for those with formal physics instruction. In 2 experiments, 98 participants dropped ball pairs…

  5. ANALISIS SENTIMENT PADA SOSIAL MEDIA TWITTER MENGGUNAKAN NAIVE BAYES CLASSIFIER TERHADAP KATA KUNCI “KURIKULUM 2013”

    Directory of Open Access Journals (Sweden)

    Dyarsa Singgih Pamungkas

    2015-11-01

    Full Text Available Twitter salah satu situs sosial media yang memungkinkan penggunanya untuk menulis tentang berbagai hal yang terjadi dalam sehari-hari. Banyak pengguna mentweet sebuah produk atau layanan yang mereka gunakan. Tweet tersebut dapat digunakan sebagai sumber data untuk menilai sentimen pada Twitter. Pengguna sering menggunakan singkatan kata dan ejaan kata yang salah, dimana dapat menyulitkan fitur yang diambil serta mengurangi ketepatan klasifikasi. Dalam penelitian ini menggunakan Twitter Search API untuk mengambil data dari twitter, penulis menerapkan proses n-gram karakter untuk seleksi fitur serta menggunakan algoritma Naive Bayes Classifier untuk mengklasifikasi sentimen secara otomatis. Penulis menggunakan 3300 data tweet tentang sentimen kepada kata kunci “kurikulum 2013”. Data tersebut diklasifikasi secara manual dan dibagi kedalam masing-masing 1000 data untuk sentimen positif, negatif dan netral. Untuk proses latih di gunakan 3000 data tweet dan 1000 tweet tiap kategori sentimentnya. Hasil penelitian ini menghasilkan sebuah sistem yang dapat mengklasifikasi sentimen secara otomatis dengan hasil pengujian 3000 data latih dan 100 tweet data ujicoba mencapai 91 %. Kata kunci : Twitter, Twitter Search API, sosial media, tweet, analisis sentimen, sentimen, N-gram, Naive Bayes Classifier.

  6. Addition of docetaxel and/or zoledronic acid to standard of care for hormone-naive prostate cancer: a cost-effectiveness analysis.

    Science.gov (United States)

    Zhang, Pengfei; Wen, Feng; Fu, Ping; Yang, Yu; Li, Qiu

    2017-07-31

    The effectiveness of the addition of docetaxel and/or zoledronic acid to the standard of care (SOC) for hormone-naive prostate cancer has been evaluated in the STAMPEDE trial. The object of the present analysis was to evaluate the cost-effectiveness of these treatment options in the treatment of advanced hormone-naive prostate cancer in China. A cost-effectiveness analysis using a Markov model was carried out from the Chinese societal perspective. The efficacy data were obtained from the STAMPEDE trial and health utilities were derived from previous studies. Transition probabilities were calculated based on the survival in each group. The primary endpoint in the analysis was the incremental cost-effectiveness ratio (ICER), and model uncertainties were explored by 1-way sensitivity analysis and probabilistic sensitivity analysis. SOC alone generated an effectiveness of 2.65 quality-adjusted life years (QALYs) at a lifetime cost of $20,969.23. At a cost of $25,001.34, SOC plus zoledronic acid was associated with 2.69 QALYs, resulting in an ICER of $100,802.75/QALY compared with SOC alone. SOC plus docetaxel gained an effectiveness of 2.85 QALYs at a cost of $28,764.66, while the effectiveness and cost data in the SOC plus zoledronic acid/docetaxel group were 2.78 QALYs and $32,640.95. Based on the results of the analysis, SOC plus zoledronic acid, SOC plus docetaxel, and SOC plus zoledronic acid/docetaxel are unlikely to be cost-effective options in patients with advanced hormone-naive prostate cancer compared with SOC alone.

  7. Professional Stereotypes of Interprofessional Education Naive Pharmacy and Nursing Students.

    Science.gov (United States)

    Thurston, Maria Miller; Chesson, Melissa M; Harris, Elaine C; Ryan, Gina J

    2017-06-01

    Objective. To assess and compare interprofessional education (IPE) naive pharmacy and nursing student stereotypes prior to completion of an IPE activity. Methods. Three hundred and twenty-three pharmacy students and 275 nursing students at Mercer University completed the Student Stereotypes Rating Questionnaire. Responses from pharmacy and nursing students were compared, and responses from different level learners within the same profession also were compared. Results. Three hundred and fifty-six (59.5%) students completed the survey. Pharmacy students viewed pharmacists more favorably than nursing students viewed pharmacists for all attributes except the ability to work independently. Additionally, nursing students viewed nurses less favorably than pharmacy students viewed nurses for academic ability and practical skills. There was some variability in stereotypes between professional years. Conclusion. This study confirms the existence of professional stereotypes, although overall student perceptions of their own profession and the other were generally positive.

  8. Professional Stereotypes of Interprofessional Education Naive Pharmacy and Nursing Students

    Science.gov (United States)

    Thurston, Maria Miller; Harris, Elaine C.; Ryan, Gina J.

    2017-01-01

    Objective. To assess and compare interprofessional education (IPE) naive pharmacy and nursing student stereotypes prior to completion of an IPE activity. Methods. Three hundred and twenty-three pharmacy students and 275 nursing students at Mercer University completed the Student Stereotypes Rating Questionnaire. Responses from pharmacy and nursing students were compared, and responses from different level learners within the same profession also were compared. Results. Three hundred and fifty-six (59.5%) students completed the survey. Pharmacy students viewed pharmacists more favorably than nursing students viewed pharmacists for all attributes except the ability to work independently. Additionally, nursing students viewed nurses less favorably than pharmacy students viewed nurses for academic ability and practical skills. There was some variability in stereotypes between professional years. Conclusion. This study confirms the existence of professional stereotypes, although overall student perceptions of their own profession and the other were generally positive. PMID:28720912

  9. Kotai Antibody Builder: automated high-resolution structural modeling of antibodies.

    Science.gov (United States)

    Yamashita, Kazuo; Ikeda, Kazuyoshi; Amada, Karlou; Liang, Shide; Tsuchiya, Yuko; Nakamura, Haruki; Shirai, Hiroki; Standley, Daron M

    2014-11-15

    Kotai Antibody Builder is a Web service for tertiary structural modeling of antibody variable regions. It consists of three main steps: hybrid template selection by sequence alignment and canonical rules, 3D rendering of alignments and CDR-H3 loop modeling. For the last step, in addition to rule-based heuristics used to build the initial model, a refinement option is available that uses fragment assembly followed by knowledge-based scoring. Using targets from the Second Antibody Modeling Assessment, we demonstrate that Kotai Antibody Builder generates models with an overall accuracy equal to that of the best-performing semi-automated predictors using expert knowledge. Kotai Antibody Builder is available at http://kotaiab.org standley@ifrec.osaka-u.ac.jp. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  10. Finger Tapping-Related Activation Differences in Treatment-Naive Pediatric Tourette Syndrome: A Comparison of the Preferred and Nonpreferred Hand

    Science.gov (United States)

    Roessner, Veit; Wittfoth, Matthias; August, Julia M.; Rothenberger, Aribert; Baudewig, Jurgen; Dechent, Peter

    2013-01-01

    Background: Disturbances of motor circuitry are commonly encountered in Tourette syndrome (TS). The aim of this study was to investigate simple motor performance differences between boys with TS and healthy controls. Methods: We attempted to provide insight into motor network alterations by studying a group of treatment-naive patients suffering…

  11. Identification of one B-cell epitope from NS1 protein of duck Tembusu virus with monoclonal antibodies.

    Directory of Open Access Journals (Sweden)

    Jinfeng Ti

    Full Text Available This study describes the identification of one linear B-cell epitope on TMUV NS1 protein with monoclonal antibody (mAb 3G2 by indirect enzyme-linked immunosorbent assay (ELISA. In this study, NS1 protein was expressed in prokaryotic expression system and purified. One mAb against NS1 protein was generated from Balb/c mice immunized with recombinant protein NS1. A set of 35 partially-overlapping polypeptides covering the entire NS1 protein was expressed with PGEX-6P-1 vector and screened with mAb 3G2. One polypeptide against the mAb was acquired and identified by indirect ELISA and western-blot. To map the epitope accurately, one or two amino acid residues were removed from the carboxy and amino terminal of polypeptide sequentially. A series of truncated oligopeptides were expressed and purified. The minimal determinant of the linear B cell epitope was recognized and identified with mAb 3G2. The accurate linear B-cell epitope was 269DEKEIV274 located in NS1 protein. Furthermore, sequence alignment showed that the epitope was highly conserved and specific among TMUV strains and other flavivirus respectively. The linear B-cell epitope of TMUV NS1 protein could benefit the development of new vaccines and diagnostic assays.

  12. Altered neural responses to heat pain in drug-naive patients with Parkinson disease.

    Science.gov (United States)

    Forkmann, Katarina; Grashorn, Wiebke; Schmidt, Katharina; Fründt, Odette; Buhmann, Carsten; Bingel, Ulrike

    2017-08-01

    Pain is a frequent but still neglected nonmotor symptom of Parkinson disease (PD). However, neural mechanisms underlying pain in PD are poorly understood. Here, we explored whether the high prevalence of pain in PD might be related to dysfunctional descending pain control. Using functional magnetic resonance imaging we explored neural responses during the anticipation and processing of heat pain in 21 PD patients (Hoehn and Yahr I-III) and 23 healthy controls (HC). Parkinson disease patients were naive to dopaminergic medication to avoid confounding drug effects. Fifteen heat pain stimuli were applied to the participants' forearm. Intensity and unpleasantness ratings were provided for each stimulus. Subjective pain perception was comparable for PD patients and HC. Neural processing, however, differed between groups: PD patients showed lower activity in several descending pain modulation regions (dorsal anterior cingulate cortex [dACC], subgenual anterior cingulate cortex, and dorsolateral prefrontal cortex [DLPFC]) and lower functional connectivity between dACC and DLPFC during pain anticipation. Parkinson disease symptom severity was negatively correlated with dACC-DLPFC connectivity indicating impaired functional coupling of pain modulatory regions with disease progression. During pain perception PD patients showed higher midcingulate cortex activity compared with HC, which also scaled with PD severity. Interestingly, dACC-DLPFC connectivity during pain anticipation was negatively associated with midcingulate cortex activity during the receipt of pain in PD patients. This study indicates altered neural processing during the anticipation and receipt of experimental pain in drug-naive PD patients. It provides first evidence for a progressive decline in descending pain modulation in PD, which might be related to the high prevalence of pain in later stages of PD.

  13. Limonoids from Melia azedarach Fruits as Inhibitors of Flaviviruses and Mycobacterium tubercolosis.

    Directory of Open Access Journals (Sweden)

    Giuseppina Sanna

    Full Text Available The biological diversity of nature is the source of a wide range of bioactive molecules. The natural products, either as pure compounds or as standardized plant extracts, have been a successful source of inspiration for the development of new drugs. The present work was carried out to investigate the cytotoxicity, antiviral and antimycobacterial activity of the methanol extract and of four identified limonoids from the fruits of Melia azedarach (Meliaceae. The extract and purified limonoids were tested in cell-based assays for antiviral activity against representatives of ssRNA, dsRNA and dsDNA viruses and against Mycobacterium tuberculosis. Very interestingly, 3-α-tigloyl-melianol and melianone showed a potent antiviral activity (EC50 in the range of 3-11μM against three important human pathogens, belonging to Flaviviridae family, West Nile virus, Dengue virus and Yellow Fever virus. Mode of action studies demonstrated that title compounds were inhibitors of West Nile virus only when added during the infection, acting as inhibitors of the entry or of a very early event of life cycle. Furthermore, 3-α-tigloyl-melianol and methyl kulonate showed interesting antimycobacterial activity (with MIC values of 29 and 70 μM respectively. The limonoids are typically lipophilic compounds present in the fruits of Melia azeradach. They are known as cytotoxic compounds against different cancer cell lines, while their potential as antiviral and antibacterial was poorly investigated. Our studies show that they may serve as a good starting point for the development of novel drugs for the treatment of infections by Flaviviruses and Mycobacterium tuberculosis, for which there is a continued need.

  14. A Roadmap for Tick-Borne Flavivirus Research in the “Omics” Era

    Directory of Open Access Journals (Sweden)

    Jeffrey M. Grabowski

    2017-12-01

    Full Text Available Tick-borne flaviviruses (TBFs affect human health globally. Human vaccines provide protection against some TBFs, and antivirals are available, yet TBF-specific control strategies are limited. Advances in genomics offer hope to understand the viral complement transmitted by ticks, and to develop disruptive, data-driven technologies for virus detection, treatment, and control. The genome assemblies of Ixodes scapularis, the North American tick vector of the TBF, Powassan virus, and other tick vectors, are providing insights into tick biology and pathogen transmission and serve as nucleation points for expanded genomic research. Systems biology has yielded insights to the response of tick cells to viral infection at the transcript and protein level, and new protein targets for vaccines to limit virus transmission. Reverse vaccinology approaches have moved candidate tick antigenic epitopes into vaccine development pipelines. Traditional drug and in silico screening have identified candidate antivirals, and target-based approaches have been developed to identify novel acaricides. Yet, additional genomic resources are required to expand TBF research. Priorities include genome assemblies for tick vectors, “omic” studies involving high consequence pathogens and vectors, and emphasizing viral metagenomics, tick-virus metabolomics, and structural genomics of TBF and tick proteins. Also required are resources for forward genetics, including the development of tick strains with quantifiable traits, genetic markers and linkage maps. Here we review the current state of genomic research on ticks and tick-borne viruses with an emphasis on TBFs. We outline an ambitious 10-year roadmap for research in the “omics era,” and explore key milestones needed to accomplish the goal of delivering three new vaccines, antivirals and acaricides for TBF control by 2030.

  15. Identification of antibody glycosylation structures that predict monoclonal antibody Fc-effector function.

    Science.gov (United States)

    Chung, Amy W; Crispin, Max; Pritchard, Laura; Robinson, Hannah; Gorny, Miroslaw K; Yu, Xiaojie; Bailey-Kellogg, Chris; Ackerman, Margaret E; Scanlan, Chris; Zolla-Pazner, Susan; Alter, Galit

    2014-11-13

    To determine monoclonal antibody (mAb) features that predict fragment crystalizable (Fc)-mediated effector functions against HIV. Monoclonal antibodies, derived from Chinese hamster ovary cells or Epstein-Barr virus-immortalized mouse heteromyelomas, with specificity to key regions of the HIV envelope including gp120-V2, gp120-V3 loop, gp120-CD4(+) binding site, and gp41-specific antibodies, were functionally profiled to determine the relative contribution of the variable and constant domain features of the antibodies in driving robust Fc-effector functions. Each mAb was assayed for antibody-binding affinity to gp140(SR162), antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP) and for the ability to bind to FcγRIIa, FcγRIIb and FcγRIIIa receptors. Antibody glycan profiles were determined by HPLC. Neither the specificity nor the affinity of the mAbs determined the potency of Fc-effector function. FcγRIIIa binding strongly predicted ADCC and decreased galactose content inversely correlated with ADCP, whereas N-glycolylneuraminic acid-containing structures exhibited enhanced ADCP. Additionally, the bi-antenary glycan arm onto which galactose was added predicted enhanced binding to FcγRIIIa and ADCC activity, independent of the specificity of the mAb. Our studies point to the specific Fc-glycan structures that can selectively promote Fc-effector functions independently of the antibody specificity. Furthermore, we demonstrated antibody glycan structures associated with enhanced ADCP activity, an emerging Fc-effector function that may aid in the control and clearance of HIV infection.

  16. C4d-negative antibody-mediated rejection with high anti-angiotensin II type I receptor antibodies in absence of donor-specific antibodies.

    Science.gov (United States)

    Fuss, Alexander; Hope, Christopher M; Deayton, Susan; Bennett, Greg Donald; Holdsworth, Rhonda; Carroll, Robert P; Coates, P Toby H

    2015-07-01

    Acute antibody-mediated rejection can occur in absence of circulating donor-specific antibodies. Agonistic antibodies targeting the anti-angiotensin II type 1 receptor (anti-AT1 R) are emerging as important non-human leucocyte antigen (HLA) antibodies. Elevated levels of anti-angiotensin II receptor antibodies were first observed in kidney transplant recipients with malignant hypertension and allograft rejection. They have now been studied in three separate kidney transplant populations and associate to frequency of rejection, severity of rejection and graft failure. We report 11 cases of biopsy-proven, Complement 4 fragment d (C4d)-negative, acute rejection occurring without circulating donor-specific anti-HLA antibodies. In eight cases, anti-angiotensin receptor antibodies were retrospectively examined. The remaining three subjects were identified from our centre's newly instituted routine anti-angiotensin receptor antibody screening. All subjects fulfilled Banff 2013 criteria for antibody-mediated rejection and all responded to anti-rejection therapy, which included plasma exchange and angiotensin receptor blocker therapy. These cases support the routine assessment of anti-AT1 R antibodies in kidney transplant recipients to identify subjects at risk. Further studies will need to determine optimal assessment protocol and the effectiveness of pre-emptive treatment with angiotensin receptor blockers. © 2015 Asian Pacific Society of Nephrology.

  17. Antibody biotechnology

    African Journals Online (AJOL)

    STORAGESEVER

    2009-07-06

    Jul 6, 2009 ... Another milestone in the history of antibodies was the work of Porter and Edelman ... transgenic animals (Lonberg et al., 1994; Green et al.,. 1994) or .... create and to screen human recombinant antibodies libraries, that is ...

  18. Expression of recombinant Antibodies

    Directory of Open Access Journals (Sweden)

    André eFrenzel

    2013-07-01

    Full Text Available Recombinant antibodies are highly specific detection probes in research, diagnostics and have emerged over the last two decades as the fastest growing class of therapeutic proteins. Antibody generation has been dramatically accelerated by in vitro selection systems, particularly phage display. An increasing variety of recombinant production systems have been developed, ranging from Gram-negative and positive bacteria, yeasts and filamentous fungi, insect cell lines, mammalian cells to transgenic plants and animals. Currently, almost all therapeutic antibodies are still produced in mammalian cell lines in order to reduce the risk of immunogenicity due to altered, non-human glycosylation patterns. However, recent developments of glycosylation-engineered yeast, insect cell lines and transgenic plants are promising to obtain antibodies with human-like post-translational modifications. Furthermore, smaller antibody fragments including bispecific antibodies without any glycosylation are successfully produced in bacteria and have advanced to clinical testing. The first therapeutic antibody products from a non-mammalian source can be expected in coming next years. In this review, we focus on current antibody production systems including their usability for different applications.

  19. T-lymphocyte subsets in HIV-infected and high-risk HIV-uninfected adolescents - Retention of naive T lymphocytes in HIV-infected adolescents

    NARCIS (Netherlands)

    Douglas, SD; Rudy, B; Muenz, L; Starr, SE; Campbell, DE; Wilson, C; Holland, C; Crowley-Nowick, P; Vermund, SH

    Background: The capacity of the immune system of adolescents to generate and repopulate naive and memory cell populations under conditions of normal homeostasis and human immunodeficiency virus (HIV) infection is largely unknown. Objective: To assess lymphocyte subsets in HIV-infected and high-risk

  20. Frontal dopamine D(2/3) receptor binding in drug-naive first-episode schizophrenic patients correlates with positive psychotic symptoms and gender

    DEFF Research Database (Denmark)

    Glenthoj, Birte Y; Mackeprang, Torben; Svarer, Claus

    2006-01-01

    BACKGROUND: The aim of the study was to examine extrastriatal dopamine D(2/3) receptor binding and psychopathology in schizophrenic patients, and to relate binding potential (BP) values to psychopathology. METHODS: Twenty-five drug-naive schizophrenic patients and 20 healthy controls were examined...

  1. Pre-existing mutations in reverse transcriptase of hepatitis B virus in treatment-naive Chinese patients with chronic hepatitis B.

    Directory of Open Access Journals (Sweden)

    Jie Xu

    Full Text Available High rate of viral replication and lacking of proofreading activity in hepatitis B virus (HBV polymerase lead to the generation of mutations in HBV virus. Mutations in the reverse transcriptase (RT region of HBV polymerase are demonstrated to be strongly associated with drug resistance during antiviral treatment. However, the presence of mutations as well as its clinical significance in treatment-naïve hepatitis patients (defined as pre-existing mutations need to be further investigated. In the present study, a total of 168 serum samples from treatment-naive chronic hepatitis B (CHB patients were collected, and the RT region of HBV polymerase was sequenced. The results showed that pre-existing mutations in the RT region of HBV polymerase were detected in 43 of 168 (25.6% treatment-naive CHB patients within which there were no well-characterized primary nucleotide analogs (NAs resistance sites. Three dominant sites at rt191, rt207 and rt226 were found mutant in 7(16.28%, 8(18.60%, and 14(32.56% samples respectively among these 43 patients. No significant correlation was found between pre-existing mutations and gender, age, HBV genotype, ALT, HBeAg or HBV DNA loads. However, patients with pre-existing RT mutations under HBeAg sero-negative status exhibited decreased HBV DNA loads, which contributed to the decreased HBV DNA loads in the total HBeAg sero-negative patients. The above investigation indicated that there was a prevalence of pre-existing mutations in RT region of HBV polymerase which might affect the serum HBV DNA level in treatment-naive CHB patients. Its effects on the occurrence of NAs resistance and the prognosis after treatment need to be further investigated.

  2. Changes of grey matter volume in first-episode drug-naive adult major depressive disorder patients with different age-onset

    Directory of Open Access Journals (Sweden)

    Zonglin Shen

    2016-01-01

    Conclusions: The GMV of the brain areas that were related to mood regulation was decreased in the first-episode, drug-naive adult patients with MDD. Adult patients with EOD and LOD exhibited different GMV changes relative to each age-matched comparison group, suggesting depressed adult patients with different age-onset might have different pathological mechanism.

  3. Effect of antibody charge and concentration on deposition of antibody to glomerular basement membrane

    International Nuclear Information System (INIS)

    Madaio, M.P.; Salant, D.J.; Adler, S.; Darby, C.; Couser, W.G.

    1984-01-01

    Fixed anionic sites within the glomerular capillary wall influence the permeation of serum proteins, the localization of various antigens, and the deposition of antibody in the subepithelial space. In anti-GBM nephritis antibody deposition occurs very rapidly to antigenic sites located relatively proximal in the glomerular capillary wall. The authors examined the influence of the glomerular charge barrier on anti-GBM antibody deposition by comparing the rate of deposition of antibodies with cationic and anionic isoelectric points. Purified sheep anti-rat GBM IgG was isolated from acid eluates of kidneys obtained 24 hr after rats were injected with sheep antiserum to rat GBM. Anti-GBM IgG was separated into cationic (pI 6.4-8.5) and anionic (pI 4.2-6.8) fractions, which were radiolabelled with 131 I and 125 I, respectively, shown to have equal antibody contents measured by in vitro binding to normal glomeruli, mixed in equal amounts, and injected in incremental doses to ten rats. At 1 hr the glomerular antibody binding of each fraction was directly related to the blood level (r . 0.95, r . 0.97) and delivery of antibody (r . 0.98, r . 0.98). Glomerular binding of cationic antibody was four times greater than anionic antibody over the entire range of deliveries studied (P less than 0.001). The authors conclude that glomerular deposition of anti-GBM antibody is directly related to blood concentration and delivery of antibody. Furthermore, the deposition of cationic antibodies to GBM antigens was significantly greater than the deposition of anionic antibodies

  4. Beyond Antibodies as Binding Partners: The Role of Antibody Mimetics in Bioanalysis.

    Science.gov (United States)

    Yu, Xiaowen; Yang, Yu-Ping; Dikici, Emre; Deo, Sapna K; Daunert, Sylvia

    2017-06-12

    The emergence of novel binding proteins or antibody mimetics capable of binding to ligand analytes in a manner analogous to that of the antigen-antibody interaction has spurred increased interest in the biotechnology and bioanalytical communities. The goal is to produce antibody mimetics designed to outperform antibodies with regard to binding affinities, cellular and tumor penetration, large-scale production, and temperature and pH stability. The generation of antibody mimetics with tailored characteristics involves the identification of a naturally occurring protein scaffold as a template that binds to a desired ligand. This scaffold is then engineered to create a superior binder by first creating a library that is then subjected to a series of selection steps. Antibody mimetics have been successfully used in the development of binding assays for the detection of analytes in biological samples, as well as in separation methods, cancer therapy, targeted drug delivery, and in vivo imaging. This review describes recent advances in the field of antibody mimetics and their applications in bioanalytical chemistry, specifically in diagnostics and other analytical methods.

  5. Antibody informatics for drug discovery

    DEFF Research Database (Denmark)

    Shirai, Hiroki; Prades, Catherine; Vita, Randi

    2014-01-01

    to the antibody science in every project in antibody drug discovery. Recent experimental technologies allow for the rapid generation of large-scale data on antibody sequences, affinity, potency, structures, and biological functions; this should accelerate drug discovery research. Therefore, a robust bioinformatic...... infrastructure for these large data sets has become necessary. In this article, we first identify and discuss the typical obstacles faced during the antibody drug discovery process. We then summarize the current status of three sub-fields of antibody informatics as follows: (i) recent progress in technologies...... for antibody rational design using computational approaches to affinity and stability improvement, as well as ab-initio and homology-based antibody modeling; (ii) resources for antibody sequences, structures, and immune epitopes and open drug discovery resources for development of antibody drugs; and (iii...

  6. CD4~+Foxp3~+ regulatory T cells converted by rapamycin from peripheral CD4~+ CD25~-naive T cells display more potent regulatory ability in vitro

    Institute of Scientific and Technical Information of China (English)

    CHEN Jian-fei; GAO Jie; ZHANG Dong; WANG Zi-han; ZHU Ji-ye

    2010-01-01

    Background Rapamycin (RAPA) is a relatively new immunosuppressant drug that functions as a serine/threonine kinase inhibitor to prevent rejection in organ transplantation. RAPA blocks activation of T-effector (Teff) cells by inhibiting the response to interleukin-2. Recently, RAPA was also shown to selectively expand the T-regulator (Treg) cell population. To date, no studies have examined the mechanism by which RAPA converts Teff cells to Treg cells. Methods Peripheral CD4~+CD25~- naive T cells were cultivated with RAPA and B cells as antigen-presenting cells (APCs) in vitro. CD4~+CD25~- T cells were harvested after 6 days and analyzed for expression of forkhead box protein 3 (Foxp3) using flow cytometry. CD4~+CD25~+CD127~- subsets as the converted Tregs were isolated from the mixed lymphocyte reactions (MLR) with CD127 negative selection, followed by CD4 and CD25 positive selection using microbeads and magnetic separation column (MSC). Moreover, mRNA was extracted from converted Tregs and C57BL/6 naive CD4~+CD25~+ T cells and Foxp3 levels were examined by quantitative real-time polymerase chain reaction (rt-PCR). A total of 1×10~5 carboxyfluorescein succinimidyl ester (CFSE)-labeled naive CD4~+CD25~- T cells/well from C57BL/6 mice were cocultured with DBA/2 or C3H maturation of dendritic cells (mDCs) (0.25×10~5/well) in 96-well round-bottom plates for 6 days. Then 1×10~5 or 0.25×10~5 converted Treg cells were added to every well as regulatory cells. Cells were harvested after 6 days of culture and analyzed for proliferation of CFSE-labeled naive CD4~+CD25~- T cells using flow cytometry. Data were analyzed using CellQuest software.Results We found that RAPA can convert peripheral CD4~+CD25~- naive T Cells to CD4~+Foxp3~+ Treg cells using B cells as APCs, and this subtype of Treg can potently suppress Teff proliferation and maintain antigenic specificity. Conclusion Our findings provide evidence that RAPA induces Treg cell conversion from Teff cells and

  7. Antibody profiling sensitivity through increased reporter antibody layering

    Science.gov (United States)

    Apel, William A; Thompson, Vicki S

    2013-02-26

    A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immune complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source. Further, an assay, such as a test for illegal drug use, can be coupled to a test for identity such that the results of the assay can be positively correlated to the subject's identity.

  8. Antibody profiling sensitivity through increased reporter antibody layering

    Energy Technology Data Exchange (ETDEWEB)

    Apel, William A.; Thompson, Vicki S.

    2017-03-28

    A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immune complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source. Further, an assay, such as a test for illegal drug use, can be coupled to a test for identity such that the results of the assay can be positively correlated to the subject's identity.

  9. Antibody profiling sensitivity through increased reporter antibody layering

    Energy Technology Data Exchange (ETDEWEB)

    Apel, William A.; Thompson, Vicki S.

    2013-02-26

    A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immune complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source. Further, an assay, such as a test for illegal drug use, can be coupled to a test for identity such that the results of the assay can be positively correlated to the subject's identity.

  10. Antibody profiling sensitivity through increased reporter antibody layering

    Energy Technology Data Exchange (ETDEWEB)

    Apel, William A.; Thompson, Vicki S

    2010-04-13

    A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immune complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source. Further, an assay, such as a test for illegal drug use, can be coupled to a test for identity such that the results of the assay can be positively correlated to the subject's identity.

  11. Children's Naive Concepts of OCD and How They Are Affected by Biomedical Versus Cognitive Behavioural Psychoeducation.

    Science.gov (United States)

    Butlin, B; Wilson, C

    2018-04-04

    How we conceptualize mental health conditions is important as it impacts on a wide range of mediators of treatment outcome. We do not know how children intuitively conceptualize obsessive-compulsive disorder (OCD), nor do we know the relative impact of biomedical or cognitive behavioural conceptual explanations, yet both are being widely used in psychoeducation for children with OCD. This study identified children's naive concepts of OCD, and the comparative impact of biomedical versus cognitive behavioural psychoeducation on perceived prognosis. A within- and between-subjects experimental design was used. After watching a video of a young person describing their OCD, 202 children completed a questionnaire examining their concepts of the condition. They repeated the questionnaire following a second equivalent video, this time preceded by either biomedical or cognitive behavioural psychoeducation. Participants' naive concepts of OCD reflected predominant models of OCD in healthcare. Even at the minimal dose of psychoeducation, participants' conceptualizations of OCD changed. Prior exposure to OCD resulted in a stronger alignment with the biomedical model. Exposure to biomedical psychoeducation resulted in participants predicting a slower recovery with less chance of complete remission. Psychoeducation for childhood OCD is impactful. Despite its wide use by clinicians and mental health services, biomedical psychoeducation appears to have deleterious effects. Children's concepts of OCD merit attention but caution should be applied in how they are targeted.

  12. 1H magnetic resonance spectroscopy evidence for occipital involvement in treatment-naive paediatric obsessive-compulsive disorder.

    Science.gov (United States)

    Ljungberg, Maria; Nilsson, Marie K L; Melin, Karin; Jönsson, Lars; Carlsson, Arvid; Carlsson, Åsa; Forssell-Aronsson, Eva; Ivarsson, Tord; Carlsson, Maria; Starck, Göran

    2017-06-01

    Obsessive-compulsive disorder (OCD) is a chronic psychiatric disorder leading to considerable distress and disability. Therapies are effective in a majority of paediatric patients, however, many only get partial response. It is therefore important to study the underlying pathophysiology of the disorder. 1H magnetic resonance spectroscopy (MRS) was used to study the concentration of brain metabolites in four different locations (cingulate gyrus and sulcus, occipital cortex, thalamus and right caudate nucleus). Treatment-naive children and adolescents with OCD (13 subjects) were compared with a group of healthy age- and gender-matched subjects (11 subjects). Multivariate analyses were performed on the concentration values. No separation between controls and patients was found. However, a correlation between metabolite concentrations and symptom severity as measured with the Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) was found. Strongest was the correlation with the CY-BOCS obsession subscore and aspartate and choline in the caudate nucleus (positively correlated with obsessions), lipids at 2 and 0.9 ppm in thalamus, and occipital glutamate+glutamine, N-acetylaspartate and myo-inosytol (negatively correlated with obsessions). The observed correlations between 1H MRS and CY-BOCS in treatment-naive patients further supports an occipital involvement in OCD. The results are consistent with our previous study on adult OCD patients. The 1H MRS data were not supportive of a separation between the patient and control groups.

  13. Identifying the white matter impairments among ART-naive HIV patients: a multivariate pattern analysis of DTI data

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Zhenchao [Shandong University, School of Mechanical, Electrical and Information Engineering, Weihai, Shandong Province (China); Institute of Automation, CAS Key Laboratory of Molecular Imaging, Beijing (China); Liu, Zhenyu; Yang, Xin; Wang, Shuo; Yu, Dongdong [Institute of Automation, CAS Key Laboratory of Molecular Imaging, Beijing (China); Li, Ruili; Li, Hongjun [Beijing YouAn Hospital, Capital Medical University, Department of Radiology, Beijing (China); Cui, Xingwei [Zhengzhou University, Cooperative Innovation Center of Internet Healthcare, Zhengzhou (China); Dong, Enqing [Shandong University, School of Mechanical, Electrical and Information Engineering, Weihai, Shandong Province (China); Tian, Jie [Institute of Automation, CAS Key Laboratory of Molecular Imaging, Beijing (China); University of Chinese Academy of Sciences, Beijing (China)

    2017-10-15

    To identify the white matter (WM) impairments of the antiretroviral therapy (ART)-naive HIV patients by conducting a multivariate pattern analysis (MVPA) of Diffusion Tensor Imaging (DTI) data We enrolled 33 ART-naive HIV patients and 32 Normal controls in the current study. Firstly, the DTI metrics in whole brain WM tracts were extracted for each subject and feed into the Least Absolute Shrinkage and Selection Operators procedure (LASSO)-Logistic regression model to identify the impaired WM tracts. Then, Support Vector Machines (SVM) model was constructed based on the DTI metrics in the impaired WM tracts to make HIV-control group classification. Pearson correlations between the WM impairments and HIV clinical statics were also investigated. Extensive HIV-related impairments were observed in the WM tracts associated with motor function, the corpus callosum (CC) and the frontal WM. With leave-one-out cross validation, accuracy of 83.08% (P=0.002) and the area under the Receiver Operating Characteristic curve of 0.9110 were obtained in the SVM classification model. The impairments of the CC were significantly correlated with the HIV clinic statics. The MVPA was sensitive to detect the HIV-related WM changes. Our findings indicated that the MVPA had considerable potential in exploring the HIV-related WM impairments. (orig.)

  14. Identifying the white matter impairments among ART-naive HIV patients: a multivariate pattern analysis of DTI data

    International Nuclear Information System (INIS)

    Tang, Zhenchao; Liu, Zhenyu; Yang, Xin; Wang, Shuo; Yu, Dongdong; Li, Ruili; Li, Hongjun; Cui, Xingwei; Dong, Enqing; Tian, Jie

    2017-01-01

    To identify the white matter (WM) impairments of the antiretroviral therapy (ART)-naive HIV patients by conducting a multivariate pattern analysis (MVPA) of Diffusion Tensor Imaging (DTI) data We enrolled 33 ART-naive HIV patients and 32 Normal controls in the current study. Firstly, the DTI metrics in whole brain WM tracts were extracted for each subject and feed into the Least Absolute Shrinkage and Selection Operators procedure (LASSO)-Logistic regression model to identify the impaired WM tracts. Then, Support Vector Machines (SVM) model was constructed based on the DTI metrics in the impaired WM tracts to make HIV-control group classification. Pearson correlations between the WM impairments and HIV clinical statics were also investigated. Extensive HIV-related impairments were observed in the WM tracts associated with motor function, the corpus callosum (CC) and the frontal WM. With leave-one-out cross validation, accuracy of 83.08% (P=0.002) and the area under the Receiver Operating Characteristic curve of 0.9110 were obtained in the SVM classification model. The impairments of the CC were significantly correlated with the HIV clinic statics. The MVPA was sensitive to detect the HIV-related WM changes. Our findings indicated that the MVPA had considerable potential in exploring the HIV-related WM impairments. (orig.)

  15. Serologic survey of potential vertebrate hosts for West Nile Virus in Poland

    Czech Academy of Sciences Publication Activity Database

    Hubálek, Zdeněk; Wegner, E.; Halouzka, Jiří; Tryjanowski, P.; Jerzak, L.; Šikutová, Silvie; Rudolf, Ivo; Kruszewicz, A. G.; Jaworski, Z.; Włodarczyk, R.

    2008-01-01

    Roč. 21, č. 2 (2008), s. 247-254 ISSN 0882-8245 R&D Projects: GA AV ČR IAA600930611 EU Projects: European Commission(XE) 10284 - EDEN Institutional research plan: CEZ:AV0Z60930519 Source of funding: R - rámcový projekt EK Keywords : antibodies – West Nile virus – Usutu virus – Flavivirus * Poland * birds * horses Subject RIV: EE - Microbiology, Virology Impact factor: 1.949, year: 2008

  16. Efficient generation of monoclonal antibodies from single rhesus macaque antibody secreting cells.

    Science.gov (United States)

    Meng, Weixu; Li, Leike; Xiong, Wei; Fan, Xuejun; Deng, Hui; Bett, Andrew J; Chen, Zhifeng; Tang, Aimin; Cox, Kara S; Joyce, Joseph G; Freed, Daniel C; Thoryk, Elizabeth; Fu, Tong-Ming; Casimiro, Danilo R; Zhang, Ningyan; A Vora, Kalpit; An, Zhiqiang

    2015-01-01

    Nonhuman primates (NHPs) are used as a preclinical model for vaccine development, and the antibody profiles to experimental vaccines in NHPs can provide critical information for both vaccine design and translation to clinical efficacy. However, an efficient protocol for generating monoclonal antibodies from single antibody secreting cells of NHPs is currently lacking. In this study we established a robust protocol for cloning immunoglobulin (IG) variable domain genes from single rhesus macaque (Macaca mulatta) antibody secreting cells. A sorting strategy was developed using a panel of molecular markers (CD3, CD19, CD20, surface IgG, intracellular IgG, CD27, Ki67 and CD38) to identify the kinetics of B cell response after vaccination. Specific primers for the rhesus macaque IG genes were designed and validated using cDNA isolated from macaque peripheral blood mononuclear cells. Cloning efficiency was averaged at 90% for variable heavy (VH) and light (VL) domains, and 78.5% of the clones (n = 335) were matched VH and VL pairs. Sequence analysis revealed that diverse IGHV subgroups (for VH) and IGKV and IGLV subgroups (for VL) were represented in the cloned antibodies. The protocol was tested in a study using an experimental dengue vaccine candidate. About 26.6% of the monoclonal antibodies cloned from the vaccinated rhesus macaques react with the dengue vaccine antigens. These results validate the protocol for cloning monoclonal antibodies in response to vaccination from single macaque antibody secreting cells, which have general applicability for determining monoclonal antibody profiles in response to other immunogens or vaccine studies of interest in NHPs.

  17. [Voxel-Based Morphometry in Medicated-naive Boys with Attention-deficit/hyperactivity Disorder(ADHD)].

    Science.gov (United States)

    Liu, Qi; Chen, Lizhou; Li, Fei; Chen, Ying; Guo, Lanting; Gong, Qiyong; Huang, Xiaoqi

    2016-06-01

    Attention-deficit/hyperactivity disorder(ADHD)is one of the most common neuro-developmental disorders occurring in childhood,characterized by symptoms of age-inappropriate inattention,hyperactivity/impulsivity,and the prevalence is higher in boys.Although gray matter volume deficits have been frequently reported for ADHD children via structural magnetic resonance imaging,few of them had specifically focused on male patients.The present study aimed to explore the alterations of gray matter volumes in medicated-naive boys with ADHD via a relatively new voxel-based morphometry technique.According to the criteria of DSM-IV-TR,43medicated-naive ADHD boys and 44age-matched healthy boys were recruited.The magnetic resonance image(MRI)scan was performed via a 3T MRI system with three-dimensional(3D)spoiled gradient recalled echo(SPGR)sequence.Voxel-based morphometry with diffeomorphic anatomical registration through exponentiated lie algebra in SPM8 was used to preprocess the3DT1-weighted images.To identify gray matter volume differences between the ADHD and the controls,voxelbased analysis of whole brain gray matter volumes between two groups were done via two sample t-test in SPM8 with age as covariate,threshold at P<0.001.Finally,compared to the controls,significantly reduced gray matter volumes were identified in the right orbitofrontal cortex(peak coordinates[-2,52,-25],t=4.01),and bilateral hippocampus(Left:peak coordinates[14,0,-18],t=3.61;Right:peak coordinates[-14,15,-28],t=3.64)of ADHD boys.Our results demonstrated obvious reduction of whole brain gray matter volumes in right orbitofrontal cortex and bilateral hippocampus in boys with ADHD.This suggests that the abnormalities of prefrontal-hippocampus circuit may be the underlying cause of the cognitive dysfunction and abnormal behavioral inhibition in medicatednaive boys with ADHD.

  18. Identification of a novel dendritic cell surface antigen defined by carbohydrate specific CD24 antibody cross-reactivity.

    Science.gov (United States)

    Williams, L A; McLellan, A D; Summers, K L; Sorg, R V; Fearnley, D B; Hart, D N

    1996-01-01

    Dendritic cells (DC) are characterized as leucocytes that lack mature lineage specific markers and stimulate naive T-lymphocyte proliferation in vitro and in vivo. The mouse heat stable antigen (HSA) participates in T lymphocyte co-stimulation and is expressed by DC isolated from thymus, skin and spleen. The human HSA homologue, CD24, is predominantly expressed by B lymphocytes and granulocytes, but its expression on DC has not been studied in detail. CD24 clearly participates in B-lymphocyte signalling but co-stimulatory activity for T lymphocytes has not yet been described. We have examined the expression of CD24 on human peripheral blood DC populations isolated directly or following in vitro culture. The CD24 antigen was absent from blood DC however, cross-reactive sialylated carbohydrate epitopes were detected on DC with some CD24 monoclonal antibodies (mAb). These CD24 mAb define a protein surface antigen, which is expressed by an immature or resting subpopulation of peripheral blood DC and is down-regulated following activation differentiation in vitro. PMID:8911149

  19. Monoclonal antibody form and function: manufacturing the right antibodies for treating drug abuse.

    Science.gov (United States)

    Peterson, Eric; Owens, S Michael; Henry, Ralph L

    2006-05-26

    Drug abuse continues to be a major national and worldwide problem, and effective treatment strategies are badly needed. Antibodies are promising therapies for the treatment of medical problems caused by drug abuse, with several candidates in preclinical and early clinical trials. Monoclonal antibodies can be designed that have customized affinity and specificity against drugs of abuse, and because antibodies can be designed in various forms, in vivo pharmacokinetic characteristics can be tailored to suit specific clinical applications (eg, long-acting for relapse prevention, or short-acting for overdose). Passive immunization with antibodies against drugs of abuse has several advantages over active immunization, but because large doses of monoclonal antibodies may be needed for each patient, efficient antibody production technology is essential. In this minireview we discuss some of the antibody forms that may be effective clinical treatments for drug abuse, as well as several current and emerging production systems that could bridge the gap from discovery to patient use.

  20. Specificity of anti-phospholipid antibodies in infectious mononucleosis: a role for anti-cofactor protein antibodies

    Science.gov (United States)

    Sorice, M; Pittoni, V; Griggi, T; Losardo, A; Leri, O; Magno, M S; Misasi, R; Valesini, G

    2000-01-01

    The antigen specificity of anti-phospholipid antibodies in infectious mononucleosis (IM) was studied using ELISA for the detection of anti-β2-glycoprotein I (β2-GPI), anti-annexin V, anti-protein S and anti-prothrombin antibodies and TLC immunostaining for the detection of anti-phospholipid antibodies. This technique enabled us to look at antibodies reacting to ‘pure’ phospholipid antigens in the absence of protein contamination. Sera from 46 patients with IM, 18 with systemic lupus erythematosus (SLE), 21 with primary anti-phospholipid antibody syndrome (PAPS), 50 with Helicobacter pylori infection and 30 healthy blood donors were tested. This study highlights anti-phospholipid antibodies in patients with IM as specific ‘pure’ anti-cardiolipin antibodies, while in PAPS and SLE patients anti-phosphatidylserine and anti-phosphatidylethanolamine antibodies were also found. This investigation also shows that the anti-cardiolipin antibodies found in IM can be present with anti-cofactor protein antibodies. The higher prevalence of anti-cofactor antibodies found in IM sera than in Helicobacter pylori sera may be due to the immunostimulatory effect and/or the polyclonal activation often observed in course of Epstein–Barr virus infection. However, anti-β2-GPI and, to a lesser extent, anti-prothrombin antibodies occur with a significantly lower prevalence in IM than in PAPS patients. This finding suggests that these antibodies should be regarded as the expression of the broad autoimmune syndrome involving the phospholipid-binding plasma proteins. PMID:10792380

  1. Radiolabeled antibodies in cancer. Oncology Overview

    International Nuclear Information System (INIS)

    1984-11-01

    Oncology Overviews are a service of the International Cancer Research Data Bank (ICRDB) Program of the National Cancer Institute, intended to facilitate and promote the exchange of information between cancer scientists by keeping them aware of literature related to their research being published by other laboratories through the world. Each Oncology Overview represents a survey of the literature associated with a selected area of cancer research. It contains abstracts of articles which have been selected and organized by researchers associated with the field. Contents: Radiolabeled antibodies--labeling and imaging techniques; Radiolabeled antibodies--carcinoembryonic antigen; Radiolabeled antibodies--alpha-fetoprotein; Radiolabeled antibodies--human chorionic gonadotropin; Radiolabeled antibodies--ferritin; Radiolabeled antibodies--imaging of colorectal tumors; Radiolabeled antibodies--imaging of malignant melanoma; Radiolabeled antibodies--imaging of urogenital tumors; Radiolabeled antibodies--imaging of thyroid tumors; Radiolabeled antibodies--other clinical studies; Radiolabeled antibodies--selected preclinical studies; Radiolabeled antibodies--reviews

  2. Antibody Engineering & Therapeutics 2016: The Antibody Society's annual meeting, December 11-15, 2016, San Diego, CA.

    Science.gov (United States)

    Larrick, James W; Alfenito, Mark R; Scott, Jamie K; Parren, Paul W H I; Burton, Dennis R; Bradbury, Andrew R M; Lemere, Cynthia A; Messer, Anne; Huston, James S; Carter, Paul J; Veldman, Trudi; Chester, Kerry A; Schuurman, Janine; Adams, Gregory P; Reichert, Janice M

    Antibody Engineering & Therapeutics, the largest meeting devoted to antibody science and technology and the annual meeting of The Antibody Society, will be held in San Diego, CA on December 11-15, 2016. Each of 14 sessions will include six presentations by leading industry and academic experts. In this meeting preview, the session chairs discuss the relevance of their topics to current and future antibody therapeutics development. Session topics include bispecifics and designer polyclonal antibodies; antibodies for neurodegenerative diseases; the interface between passive and active immunotherapy; antibodies for non-cancer indications; novel antibody display, selection and screening technologies; novel checkpoint modulators / immuno-oncology; engineering antibodies for T-cell therapy; novel engineering strategies to enhance antibody functions; and the biological Impact of Fc receptor engagement. The meeting will open with keynote speakers Dennis R. Burton (The Scripps Research Institute), who will review progress toward a neutralizing antibody-based HIV vaccine; Olivera J. Finn, (University of Pittsburgh School of Medicine), who will discuss prophylactic cancer vaccines as a source of therapeutic antibodies; and Paul Richardson (Dana-Farber Cancer Institute), who will provide a clinical update on daratumumab for multiple myeloma. In a featured presentation, a representative of the World Health Organization's INN expert group will provide a perspective on antibody naming. "Antibodies to watch in 2017" and progress on The Antibody Society's 2016 initiatives will be presented during the Society's special session. In addition, two pre-conference workshops covering ways to accelerate antibody drugs to the clinic and the applications of next-generation sequencing in antibody discovery and engineering will be held on Sunday December 11, 2016.

  3. Complement-fixing antibodies against denatured HLA and MICA antigens are associated with antibody mediated rejection.

    Science.gov (United States)

    Cai, Junchao; Terasaki, Paul I; Zhu, Dong; Lachmann, Nils; Schönemann, Constanze; Everly, Matthew J; Qing, Xin

    2016-02-01

    We have found antibodies against denatured HLA class I antigens in the serum of allograft recipients which were not significantly associated with graft failure. It is unknown whether transplant recipients also have denatured HLA class II and MICA antibodies. The effects of denatured HLA class I, class II, and MICA antibodies on long-term graft outcome were further investigated based on their ability to fix complement c1q. In this 4-year retrospective cohort study, post-transplant sera from 975 kidney transplant recipients were tested for antibodies against denatured HLA/MICA antigens and these antibodies were further classified based on their ability to fix c1q. Thirty percent of patients had antibodies against denatured HLA class I, II, or MICA antigens. Among them, 8.5% and 21.5% of all patients had c1q-fixing and non c1q-fixing antibodies respectively. There was no significant difference on graft survival between patients with or without antibodies against denatured HLA/MICA. However, when these antibodies were further classified according to their ability to fix c1q, patients with c1q-fixing antibodies had a significantly lower graft survival rate than patients without antibodies or patients with non c1q-fixing antibodies (p=0.008). In 169 patients who lost renal grafts, 44% of them had c1q-fixing antibodies against denatured HLA/MICA antigens, which was significantly higher than that in patients with functioning renal transplants (25%, pantibodies were more significantly associated with graft failure caused by AMR (72.73%) or mixed AMR/CMR (61.9%) as compared to failure due to CMR (35.3%) or other causes (39.2%) (p=0.026). Transplant recipients had antibodies against denatured HLA class I, II, and MICA antigens. However, only c1q-fixing antibodies were associated with graft failure which was related to antibody mediated rejection. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Identification of antigen-specific human monoclonal antibodies using high-throughput sequencing of the antibody repertoire.

    Science.gov (United States)

    Liu, Ju; Li, Ruihua; Liu, Kun; Li, Liangliang; Zai, Xiaodong; Chi, Xiangyang; Fu, Ling; Xu, Junjie; Chen, Wei

    2016-04-22

    High-throughput sequencing of the antibody repertoire provides a large number of antibody variable region sequences that can be used to generate human monoclonal antibodies. However, current screening methods for identifying antigen-specific antibodies are inefficient. In the present study, we developed an antibody clone screening strategy based on clone dynamics and relative frequency, and used it to identify antigen-specific human monoclonal antibodies. Enzyme-linked immunosorbent assay showed that at least 52% of putative positive immunoglobulin heavy chains composed antigen-specific antibodies. Combining information on dynamics and relative frequency improved identification of positive clones and elimination of negative clones. and increase the credibility of putative positive clones. Therefore the screening strategy could simplify the subsequent experimental screening and may facilitate the generation of antigen-specific antibodies. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Precisely Molded Nanoparticle Displaying DENV-E Proteins Induces Robust Serotype-Specific Neutralizing Antibody Responses.

    Directory of Open Access Journals (Sweden)

    Stefan W Metz

    2016-10-01

    Full Text Available Dengue virus (DENV is the causative agent of dengue fever and dengue hemorrhagic fever. The virus is endemic in over 120 countries, causing over 350 million infections per year. Dengue vaccine development is challenging because of the need to induce simultaneous protection against four antigenically distinct DENV serotypes and evidence that, under some conditions, vaccination can enhance disease due to specific immunity to the virus. While several live-attenuated tetravalent dengue virus vaccines display partial efficacy, it has been challenging to induce balanced protective immunity to all 4 serotypes. Instead of using whole-virus formulations, we are exploring the potentials for a particulate subunit vaccine, based on DENV E-protein displayed on nanoparticles that have been precisely molded using Particle Replication in Non-wetting Template (PRINT technology. Here we describe immunization studies with a DENV2-nanoparticle vaccine candidate. The ectodomain of DENV2-E protein was expressed as a secreted recombinant protein (sRecE, purified and adsorbed to poly (lactic-co-glycolic acid (PLGA nanoparticles of different sizes and shape. We show that PRINT nanoparticle adsorbed sRecE without any adjuvant induces higher IgG titers and a more potent DENV2-specific neutralizing antibody response compared to the soluble sRecE protein alone. Antigen trafficking indicate that PRINT nanoparticle display of sRecE prolongs the bio-availability of the antigen in the draining lymph nodes by creating an antigen depot. Our results demonstrate that PRINT nanoparticles are a promising platform for delivering subunit vaccines against flaviviruses such as dengue and Zika.

  6. Metabolomics reveals distinct, antibody-independent, molecular signatures of MS, AQP4-antibody and MOG-antibody disease.

    Science.gov (United States)

    Jurynczyk, Maciej; Probert, Fay; Yeo, Tianrong; Tackley, George; Claridge, Tim D W; Cavey, Ana; Woodhall, Mark R; Arora, Siddharth; Winkler, Torsten; Schiffer, Eric; Vincent, Angela; DeLuca, Gabriele; Sibson, Nicola R; Isabel Leite, M; Waters, Patrick; Anthony, Daniel C; Palace, Jacqueline

    2017-12-06

    The overlapping clinical features of relapsing remitting multiple sclerosis (RRMS), aquaporin-4 (AQP4)-antibody (Ab) neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein (MOG)-Ab disease mean that detection of disease specific serum antibodies is the gold standard in diagnostics. However, antibody levels are not prognostic and may become undetectable after treatment or during remission. Therefore, there is still a need to discover antibody-independent biomarkers. We sought to discover whether plasma metabolic profiling could provide biomarkers of these three diseases and explore if the metabolic differences are independent of antibody titre. Plasma samples from 108 patients (34 RRMS, 54 AQP4-Ab NMOSD, and 20 MOG-Ab disease) were analysed by nuclear magnetic resonance spectroscopy followed by lipoprotein profiling. Orthogonal partial-least squares discriminatory analysis (OPLS-DA) was used to identify significant differences in the plasma metabolite concentrations and produce models (mathematical algorithms) capable of identifying these diseases. In all instances, the models were highly discriminatory, with a distinct metabolite pattern identified for each disease. In addition, OPLS-DA identified AQP4-Ab NMOSD patient samples with low/undetectable antibody levels with an accuracy of 92%. The AQP4-Ab NMOSD metabolic profile was characterised by decreased levels of scyllo-inositol and small high density lipoprotein particles along with an increase in large low density lipoprotein particles relative to both RRMS and MOG-Ab disease. RRMS plasma exhibited increased histidine and glucose, along with decreased lactate, alanine, and large high density lipoproteins while MOG-Ab disease plasma was defined by increases in formate and leucine coupled with decreased myo-inositol. Despite overlap in clinical measures in these three diseases, the distinct plasma metabolic patterns support their distinct serological profiles and confirm that these

  7. IBC's 23rd Annual Antibody Engineering, 10th Annual Antibody Therapeutics international conferences and the 2012 Annual Meeting of The Antibody Society: December 3-6, 2012, San Diego, CA.

    Science.gov (United States)

    Klöhn, Peter-Christian; Wuellner, Ulrich; Zizlsperger, Nora; Zhou, Yu; Tavares, Daniel; Berger, Sven; Zettlitz, Kirstin A; Proetzel, Gabriele; Yong, May; Begent, Richard H J; Reichert, Janice M

    2013-01-01

    The 23rd Annual Antibody Engineering, 10th Annual Antibody Therapeutics international conferences, and the 2012 Annual Meeting of The Antibody Society, organized by IBC Life Sciences with contributions from The Antibody Society and two Scientific Advisory Boards, were held December 3-6, 2012 in San Diego, CA. The meeting drew over 800 participants who attended sessions on a wide variety of topics relevant to antibody research and development. As a prelude to the main events, a pre-conference workshop held on December 2, 2012 focused on intellectual property issues that impact antibody engineering. The Antibody Engineering Conference was composed of six sessions held December 3-5, 2012: (1) From Receptor Biology to Therapy; (2) Antibodies in a Complex Environment; (3) Antibody Targeted CNS Therapy: Beyond the Blood Brain Barrier; (4) Deep Sequencing in B Cell Biology and Antibody Libraries; (5) Systems Medicine in the Development of Antibody Therapies/Systematic Validation of Novel Antibody Targets; and (6) Antibody Activity and Animal Models. The Antibody Therapeutics conference comprised four sessions held December 4-5, 2012: (1) Clinical and Preclinical Updates of Antibody-Drug Conjugates; (2) Multifunctional Antibodies and Antibody Combinations: Clinical Focus; (3) Development Status of Immunomodulatory Therapeutic Antibodies; and (4) Modulating the Half-Life of Antibody Therapeutics. The Antibody Society's special session on applications for recording and sharing data based on GIATE was held on December 5, 2012, and the conferences concluded with two combined sessions on December 5-6, 2012: (1) Development Status of Early Stage Therapeutic Antibodies; and (2) Immunomodulatory Antibodies for Cancer Therapy.

  8. Generation of HER2 monoclonal antibodies using epitopes of a rabbit polyclonal antibody.

    Science.gov (United States)

    Hu, Francis Jingxin; Uhlen, Mathias; Rockberg, Johan

    2014-01-25

    One of the issues in using polyclonal antibodies is the limited amount of reagent available from an immunisation, leading to batch-to-batch variation and difficulties in obtaining the same antibody performance when the same antigen is re-immunised into several separate animals. This led to the development of hybridoma technology allowing, at least theoretically, for an unlimited production of a specific binder. Nevertheless, polyclonal antibodies are widely used in research and diagnostics and there exists a need for robust methods to convert a polyclonal antibody with good binding performance into a renewable monoclonal with identical or similar binding specificity. Here we have used precise information regarding the functional recognition sequence (epitope) of a rabbit polyclonal antibody with attractive binding characteristics as the basis for generation of a renewable mouse monoclonal antibody. First, the original protein fragment antigen was used for immunisation and generation of mouse hybridoma, without obtaining binders to the same epitope region. Instead a peptide designed using the functional epitope and structural information was synthesised and used for hybridoma production. Several of the monoclonal antibodies generated were found to have similar binding characteristics to those of the original polyclonal antibody. These monoclonal antibodies detected native HER2 on cell lines and were also able to stain HER2 in immunohistochemistry using xenografted mice, as well as human normal and cancer tissues. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Thermodynamics of antibody-antigen interaction revealed by mutation analysis of antibody variable regions.

    Science.gov (United States)

    Akiba, Hiroki; Tsumoto, Kouhei

    2015-07-01

    Antibodies (immunoglobulins) bind specific molecules (i.e. antigens) with high affinity and specificity. In order to understand their mechanisms of recognition, interaction analysis based on thermodynamic and kinetic parameters, as well as structure determination is crucial. In this review, we focus on mutational analysis which gives information about the role of each amino acid residue in antibody-antigen interaction. Taking anti-hen egg lysozyme antibodies and several anti-small molecule antibodies, the energetic contribution of hot-spot and non-hot-spot residues is discussed in terms of thermodynamics. Here, thermodynamics of the contribution from aromatic, charged and hydrogen bond-forming amino acids are discussed, and their different characteristics have been elucidated. The information gives fundamental understanding of the antibody-antigen interaction. Furthermore, the consequences of antibody engineering are analysed from thermodynamic viewpoints: humanization to reduce immunogenicity and rational design to improve affinity. Amino acid residues outside hot-spots in the interface play important roles in these cases, and thus thermodynamic and kinetic parameters give much information about the antigen recognition. Thermodynamic analysis of mutant antibodies thus should lead to advanced strategies to design and select antibodies with high affinity. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  10. The interfacial character of antibody paratopes: analysis of antibody-antigen structures.

    Science.gov (United States)

    Nguyen, Minh N; Pradhan, Mohan R; Verma, Chandra; Zhong, Pingyu

    2017-10-01

    In this study, computational methods are applied to investigate the general properties of antigen engaging residues of a paratope from a non-redundant dataset of 403 antibody-antigen complexes to dissect the contribution of hydrogen bonds, hydrophobic, van der Waals contacts and ionic interactions, as well as role of water molecules in the antigen-antibody interface. Consistent with previous reports using smaller datasets, we found that Tyr, Trp, Ser, Asn, Asp, Thr, Arg, Gly, His contribute substantially to the interactions between antibody and antigen. Furthermore, antibody-antigen interactions can be mediated by interfacial waters. However, there is no reported comprehensive analysis for a large number of structured waters that engage in higher ordered structures at the antibody-antigen interface. From our dataset, we have found the presence of interfacial waters in 242 complexes. We present evidence that suggests a compelling role of these interfacial waters in interactions of antibodies with a range of antigens differing in shape complementarity. Finally, we carry out 296 835 pairwise 3D structure comparisons of 771 structures of contact residues of antibodies with their interfacial water molecules from our dataset using CLICK method. A heuristic clustering algorithm is used to obtain unique structural similarities, and found to separate into 368 different clusters. These clusters are used to identify structural motifs of contact residues of antibodies for epitope binding. This clustering database of contact residues is freely accessible at http://mspc.bii.a-star.edu.sg/minhn/pclick.html. minhn@bii.a-star.edu.sg, chandra@bii.a-star.edu.sg or zhong_pingyu@immunol.a-star.edu.sg. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  11. Mouse-specific antibody responses to a monoclonal antibody during repeated immunoscintigraphy investigations: Comparison of antibody titres and imaging studies in a rat model

    International Nuclear Information System (INIS)

    Pimm, M.V.; Gribben, S.J.; Markham, A.J.; Perkins, A.C.

    1990-01-01

    As a model for human mouse-specific antibody responses in patients undergoing immunoscintigraphy, we have investigated in rats the production of mouse-specific antibodies (MA) to the mouse monoclonal antibody 791T/36. At intervals of between 5 and 16 weeks the rats were given repeated cycles of intravenous (IV) injections of antibody with or without a simultaneous intradermal (ID) injection. The IV dose was 60 μg/kg, a dose similar to that used in many clinical immunoscintigraphy studies. The ID injection was 2 μg, which mimicks the skin test dose often given in clinical imaging protocols. The study was carried out with both 131 I-labelled antibody and with antibody labelled with 111 In by DTPA chelation. MA was measured with a passive haemagglutination assay using sheep red blood cells coated with the monoclonal antibody. Of rats given ID injections of unlabelled antibody at the same time as the IV imaging doses, 9/20 produced MA during 4 cycles of injections. In contrast, only 2/16 rats given only the IV dose produced MA. Both 131 I- and 111 In-labelled antibody appeared equally immunogenic with 5/18 and 6/18 overall responders, respectively. The production of MA was associated with a significant perturbation in the biodistribution of the IV dose of labelled antibody as seen by gamma-camera imaging of the rats given 111 In-labelled antibody. There was clearance of immune complexes to the liver, this organ accumulating up to 90% of the whole body count rate of radiolabel. MA titres of between 1/100 and 1/78000 caused equal perturbation of biodistribution, although below 1/100 the effect was more variable. (orig.)

  12. Antibodies to poliovirus detected by immunoradiometric assay with a monoclonal antibody

    International Nuclear Information System (INIS)

    Spitz, M.; Fossati, C.A.; Schild, G.C.; Spitz, L.; Brasher, M.

    1982-01-01

    An immunoradiometric assay (IRMA) for the assay of antibodies to poliovirus antigens is described. Dilutions of the test sera or whole (finger prick) blood samples were incubated with the poliovirus antigen bound to a solid phase and the specific antibody was detected by the addition of a mouse anti-human IgG monoclonal antibody (McAb), which was itself revealed by iodinated sheep IgG antimouse F(ab). The authors have shown that this technique is suitable for the estimation of IgG anti-poliovirus antibodies induced in children following polio vaccine. The present study shows that SPRIA provides a simple and inexpensive method for serological studies with poliovirus particularly for use in large-scale surveys. (Auth.)

  13. Antibodies to poliovirus detected by immunoradiometric assay with a monoclonal antibody

    Energy Technology Data Exchange (ETDEWEB)

    Spitz, M.; Fossati, C.A.; Schild, G.C.; Spitz, L.; Brasher, M. (National Inst. for Biological Standards and Control, London (UK))

    1982-10-01

    An immunoradiometric assay (IRMA) for the assay of antibodies to poliovirus antigens is described. Dilutions of the test sera or whole (finger prick) blood samples were incubated with the poliovirus antigen bound to a solid phase and the specific antibody was detected by the addition of a mouse anti-human IgG monoclonal antibody (McAb), which was itself revealed by iodinated sheep IgG antimouse F(ab). The authors have shown that this technique is suitable for the estimation of IgG anti-poliovirus antibodies induced in children following polio vaccine. The present study shows that SPRIA provides a simple and inexpensive method for serological studies with poliovirus particularly for use in large-scale surveys.

  14. Monoclonal antibodies for treating cancer

    International Nuclear Information System (INIS)

    Dillman, R.O.

    1989-01-01

    The purpose of this study is to assess the current status of in-vivo use of monoclonal antibodies for treating cancer. Publications appearing between 1980 and 1988 were identified by computer searches using MEDLINE and CANCERLIT, by reviewing the table of contents of recently published journals, and by searching bibliographies of identified books and articles. More than 700 articles, including peer-reviewed articles and book chapters, were identified and selected for analysis. The literature was reviewed and 235 articles were selected as relevant and representative of the current issues and future applications for in-vivo monoclonal antibodies for cancer therapy and of the toxicity and efficacy which has been associated with clinical trials. Approaches include using antibody alone (interacting with complement or effector cells or binding directly with certain cell receptors) and immunoconjugates (antibody coupled to radioisotopes, drugs, toxins, or other biologicals). Most experience has been with murine antibodies. Trials of antibody alone and radiolabeled antibodies have confirmed the feasibility of this approach and the in-vivo trafficking of antibodies to tumor cells. However, tumor cell heterogeneity, lack of cytotoxicity, and the development of human antimouse antibodies have limited clinical efficacy. Although the immunoconjugates are very promising, heterogeneity and the antimouse immune response have hampered this approach as has the additional challenge of chemically or genetically coupling antibody to cytotoxic agents. As a therapeutic modality, monoclonal antibodies are still promising but their general use will be delayed for several years. New approaches using human antibodies and reducing the human antiglobulin response should facilitate treatment. 235 references

  15. Heavy chain only antibodies

    DEFF Research Database (Denmark)

    Moghimi, Seyed Moein; Rahbarizadeh, Fatemeh; Ahmadvand, Davoud

    2013-01-01

    Unlike conventional antibodies, heavy chain only antibodies derived from camel contain a single variable domain (VHH) and two constant domains (CH2 and CH3). Cloned and isolated VHHs possess unique properties that enable them to excel conventional therapeutic antibodies and their smaller antigen...

  16. 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

  17. Polyclonal and monoclonal antibodies in clinic.

    Science.gov (United States)

    Wootla, Bharath; Denic, Aleksandar; Rodriguez, Moses

    2014-01-01

    Immunoglobulins (Ig) or antibodies are heavy plasma proteins, with sugar chains added to amino-acid residues by N-linked glycosylation and occasionally by O-linked glycosylation. The versatility of antibodies is demonstrated by the various functions that they mediate such as neutralization, agglutination, fixation with activation of complement and activation of effector cells. Naturally occurring antibodies protect the organism against harmful pathogens, viruses and infections. In addition, almost any organic chemical induces antibody production of antibodies that would bind specifically to the chemical. These antibodies are often produced from multiple B cell clones and referred to as polyclonal antibodies. In recent years, scientists have exploited the highly evolved machinery of the immune system to produce structurally and functionally complex molecules such as antibodies from a single B clone, heralding the era of monoclonal antibodies. Most of the antibodies currently in the clinic, target components of the immune system, are not curative and seek to alleviate symptoms rather than cure disease. Our group used a novel strategy to identify reparative human monoclonal antibodies distinct from conventional antibodies. In this chapter, we discuss the therapeutic relevance of both polyclonal and monoclonal antibodies in clinic.

  18. Zika virus infection confers protection against West Nile virus challenge in mice.

    Science.gov (United States)

    Vázquez-Calvo, Ángela; Blázquez, Ana-Belén; Escribano-Romero, Estela; Merino-Ramos, Teresa; Saiz, Juan-Carlos; Martín-Acebes, Miguel A; Jiménez de Oya, Nereida

    2017-09-20

    Flaviviruses are RNA viruses that constitute a worrisome threat to global human and animal health. Zika virus (ZIKV), which was initially reported to cause a mild disease, recently spread in the Americas, infecting millions of people. During this recent epidemic, ZIKV infection has been linked to serious neurological diseases and birth defects, specifically Guillain-Barrè syndrome (GBS) and microcephaly. Because information about ZIKV immunity remains scarce, we assessed the humoral response of immunocompetent mice to infection with three viral strains of diverse geographical origin (Africa, Asia and America). No infected animals showed any sign of disease or died after infection. However, specific neutralizing antibodies were elicited in all infected mice. Considering the rapid expansion of ZIKV throughout the American continent and its co-circulation with other medically relevant flaviviruses, such as West Nile virus (WNV), the induction of protective immunity between ZIKV and WNV was analyzed. Remarkably, protection after challenge with WNV was observed in mice previously infected with ZIKV, as survival rates were significantly higher than in control mice. Moreover, previous ZIKV infection enhanced the humoral immune response against WNV. These findings may be relevant in geographical areas where both ZIKV and WNV co-circulate, as well as for the future development of broad-spectrum flavivirus vaccines.

  19. Acetylcholine receptor antibody

    Science.gov (United States)

    ... medlineplus.gov/ency/article/003576.htm Acetylcholine receptor antibody To use the sharing features on this page, please enable JavaScript. Acetylcholine receptor antibody is a protein found in the blood of ...

  20. Stratification of antibody-positive subjects by antibody level reveals an impact of immunogenicity on pharmacokinetics.

    Science.gov (United States)

    Zhou, Lei; Hoofring, Sarah A; Wu, Yu; Vu, Thuy; Ma, Peiming; Swanson, Steven J; Chirmule, Narendra; Starcevic, Marta

    2013-01-01

    The availability of highly sensitive immunoassays enables the detection of antidrug antibody (ADA) responses of various concentrations and affinities. The analysis of the impact of antibody status on drug pharmacokinetics (PK) is confounded by the presence of low-affinity or low-concentration antibody responses within the dataset. In a phase 2 clinical trial, a large proportion of subjects (45%) developed ADA following weekly dosing with AMG 317, a fully human monoclonal antibody therapeutic. The antibody responses displayed a wide range of relative concentrations (30 ng/mL to >13 μg/mL) and peaked at various times during the study. To evaluate the impact of immunogenicity on PK, AMG 317 concentration data were analyzed following stratification by dose group, time point, antibody status (positive or negative), and antibody level (relative concentration). With dose group as a stratifying variable, a moderate reduction in AMG 317 levels (AMG 317 levels was revealed when antibody data was stratified by both time point and antibody level. In general, high ADA concentrations (>500 ng/mL) and later time points (week 12) were associated with significantly (up to 97%) lower trough AMG 317 concentrations. The use of quasi-quantitative antibody data and appropriate statistical methods was critical for the most comprehensive evaluation of the impact of immunogenicity on PK.

  1. Re-engineering therapeutic antibodies for Alzheimer's disease as blood-brain barrier penetrating bi-specific antibodies.

    Science.gov (United States)

    Pardridge, William M

    2016-12-01

    Therapeutic antibodies are large molecule drugs that do not cross the blood-brain barrier (BBB). Therefore, drug development of therapeutic antibodies for Alzheimer's disease (AD) requires that these molecules be re-engineered to enable BBB delivery. This is possible by joining the therapeutic antibody with a transporter antibody, resulting in the engineering of a BBB-penetrating bispecific antibody (BSA). Areas covered: The manuscript covers transporter antibodies that cross the BBB via receptor-mediated transport systems on the BBB, such as the insulin receptor or transferrin receptor. Furthermore, it highlights therapeutic antibodies for AD that target the Abeta amyloid peptide, beta secretase-1, or the metabotropic glutamate receptor-1. BSAs are comprised of both the transporter antibody and the therapeutic antibody, as well as IgG constant region, which can induce immune tolerance or trigger transport via Fc receptors. Expert opinion: Multiple types of BSA molecular designs have been used to engineer BBB-penetrating BSAs, which differ in valency and spatial orientation of the transporter and therapeutic domains of the BSA. The plasma pharmacokinetics and dosing regimens of BSAs differ from that of conventional therapeutic antibodies. BBB-penetrating BSAs may be engineered in the future as new treatments of AD, as well as other neural disorders.

  2. Antinuclear antibody panel

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003535.htm Antinuclear antibody panel To use the sharing features on this page, please enable JavaScript. The antinuclear antibody panel is a blood test that looks at ...

  3. Tumor imaging with monoclonal antibodies

    International Nuclear Information System (INIS)

    Haisma, H.; Hilgers, J.

    1987-01-01

    Many monoclonal antibodies directed against tumor-associated antigens have been identified, but so far none of these are tumor specific. Polyclonal and monoclonal antibodies have been used for imaging of a wide variety of tumors with success. Radiolabeling of antibody is usually done with iodine isotopes of which 123 I is the best candidate for radioimmunodetection purposes. The labeling of antibodies through chelates makes it possible to use metal radioisotopes like 111 In, which is the best radioisotope for imaging with monoclonal antibodies due to its favorable half-life of 2.5 days. Usually imaging cannot be performed within 24 h after injection, but clearance of antibody can be increased by using F(ab) 2 of Fab. Another approach is to clear non-bound antibody by a second antibody, directed against the first. The detection limit of immunoimaging is about 2 cm, but will be improved by tomography or SPECT. There is still a high false positive and false negative rate, which makes it impossible to use radioimmunodetection as the only technique for diagnosis of tumors. In combination with other detection techniques, tumor imaging with monoclonal antibodies can improve diagnosis. 44 refs.; 3 tabs

  4. Investigate-and-redesign tasks as a context for learning and doing science and technology: A study of naive, novice and expert high school and adult designers doing product comparisons and redesign tasks

    Science.gov (United States)

    Crismond, David Paul

    This thesis studied high school students and adults with varying degrees of design experience doing two technology investigate-and-redesign (I&R) tasks. Each involved subjects investigating products, designing experiments to compare them fairly, and then redesigning the devices. A total of 25 pairs of subjects participated in this investigation and included naive and novice high school designers, as well as naive, novice, and expert adult designers. Subjects of similar age and design experience worked in same-gender teams and met for two 2-hour sessions. The essential research question of this thesis was: "What process skills and concepts do naive, novice and expert designers use and learn when investigating devices, designing experiments, and redesigning the devices?" Three methodologies were used to gather and analyze the data: clinical interviewing (Piaget, 1929/1960), protocol analysis (Ericsson & Simon, 1984) and interaction analysis (Jordan and Henderson, 1995). The thesis provides composite case-studies of 10 of the 50 test sessions, buttressed by descriptions of performance trends for all subjects. Given the small sample sizes involved, the findings are by necessity tentative and not supported by statistical analysis: (1) I&R activities are engaging, less time-intensive complements to design-and-build tasks, which involve simple mechanical devices and carry with them a host of potential "alternative understandings" in science and technology. Much gets learned during these tasks, more involving "device knowledge" and "device inquiry skills" than "big ideas" in science and technology. (2) Redesign tasks scaffold naive and novice designers to improved performance in the multidimensional and context-specific activity of design. The performances of naive and novice designers were more like that of expert designers when redesigning existing devices than when doing start-from-scratch designing. (3) Conceptual redesign involved more analysis- than synthesis

  5. Improved reliability of serological tools for the diagnosis of West Nile fever in horses within Europe.

    Directory of Open Access Journals (Sweden)

    Cécile Beck

    2017-09-01

    Full Text Available West Nile Fever is a zoonotic disease caused by a mosquito-borne flavivirus, WNV. By its clinical sensitivity to the disease, the horse is a useful sentinel of infection. Because of the virus' low-level, short-term viraemia in horses, the primary tools used to diagnose WNV are serological tests. Inter-laboratory proficiency tests (ILPTs were held in 2010 and 2013 to evaluate WNV serological diagnostic tools suited for the European network of National Reference Laboratories (NRLs for equine diseases. These ILPTs were designed to evaluate the laboratories' and methods' performances in detecting WNV infection in horses through serology. The detection of WNV immunoglobulin G (IgG antibodies by ELISA is widely used in Europe, with 17 NRLs in 2010 and 20 NRLs in 2013 using IgG WNV assays. Thanks to the development of new commercial IgM capture kits, WNV IgM capture ELISAs were rapidly implemented in NRLs between 2010 (4 NRLs and 2013 (13 NRLs. The use of kits allowed the quick standardisation of WNV IgG and IgM detection assays in NRLs with more than 95% (20/21 and 100% (13/13 of satisfactory results respectively in 2013. Conversely, virus neutralisation tests (VNTs were implemented in 33% (7/21 of NRLs in 2013 and their low sensitivity was evidenced in 29% (2/7 of NRLs during this ILPT. A comparison of serological diagnostic methods highlighted the higher sensitivity of IgG ELISAs compared to WNV VNTs. They also revealed that the low specificity of IgG ELISA kits meant that it could detect animals infected with other flaviviruses. In contrast VNT and IgM ELISA assays were highly specific and did not detect antibodies against related flaviviruses. These results argue in favour of the need for and development of new, specific serological diagnostic assays that could be easily transferred to partner laboratories.

  6. Executed Movement Using EEG Signals through a Naive Bayes Classifier

    Directory of Open Access Journals (Sweden)

    Juliano Machado

    2014-11-01

    Full Text Available Recent years have witnessed a rapid development of brain-computer interface (BCI technology. An independent BCI is a communication system for controlling a device by human intension, e.g., a computer, a wheelchair or a neuroprosthes is, not depending on the brain’s normal output pathways of peripheral nerves and muscles, but on detectable signals that represent responsive or intentional brain activities. This paper presents a comparative study of the usage of the linear discriminant analysis (LDA and the naive Bayes (NB classifiers on describing both right- and left-hand movement through electroencephalographic signal (EEG acquisition. For the analysis, we considered the following input features: the energy of the segments of a band pass-filtered signal with the frequency band in sensorimotor rhythms and the components of the spectral energy obtained through the Welch method. We also used the common spatial pattern (CSP filter, so as to increase the discriminatory activity among movement classes. By using the database generated by this experiment, we obtained hit rates up to 70%. The results are compatible with previous studies.

  7. Radioimmunoassay of class-specific antibodies (RIACA): chicken antibodies to DNP

    International Nuclear Information System (INIS)

    Viljanen, M.K.; Granfors, K.; Toivanen, P.

    1977-01-01

    A radioimmunological method for the quantitation of class-specific antibodies has been developed. The method allows the quantitation of nanogram per ml concentrations of IgG and IgM-anti-DNP antibodies without any physical or chemical pretreatment of the sample. DNP was coupled covalently to a cyanogen bromide activated paper disk with the augmentation of lysine molecule. Anti-DNP antibodies were allowed to react with the coupled DNP and then quantitated by their capacity to bind 125 I-labelled anti-chicken-μ or anti-chicken-γ. The inter-assay variation coefficients ranged from 8.1 to 14.7% and the mean standard deviations of duplicate determinations were about 11%. The combination of this method with the exact immunoradiometric quantitation of the total serum IgM and IgG, and with an immunoabsorption technique, makes it possible to quantitate class-specific antibodies on weight units

  8. Multisensory interaction in vibrotactile detection and discrimination of amplitude modulation: insights from expert MFS surgeons and naive participants

    Directory of Open Access Journals (Sweden)

    Korman Maria

    2011-12-01

    Full Text Available Perception of vibration during drilling demands integration of haptic and auditory information with force information. In this study we explored the ability to detect and discriminate changes in vibrotactile stimuli amplitude based either on purely haptic feedback or together with congruent synthesized auditory cues in groups of naive subjects and expert surgeons. Our results point toward the complex influence of multimodal experience during vibration perception. First, in naive subjects, we showed that detection and discrimination of amplitude change in complex vibro-tactile stimulus is selectively sensitive to combination of modality and previous experience. In the domain of discrimination, our results suggest that bi-modal performance is always better than uni-modal performance regardless of order of experience. Second, experiments with expert surgeons revealed that expertise in complex skill of maxilla-facial surgery strongly relies on enhanced touch perception, as measured in reaction times and discrimination ability in bi-modal vibro-auditory conditions. These observations suggest that acquisition of mandibular surgery skill has brought to an enhanced representation of vibro-tactile modulations in relevant stimuli ranges. Altogether, our results provide basis to assume that during acquisition of mandibular drilling skill, trainees may benefit from training of relevant basic aspects of touch perception - sensitivity to vibration and accompanying modulations of sound.

  9. [Construction of human phage antibody library and screening for human monoclonal antibodies of amylin].

    Science.gov (United States)

    Gong, Qian; Li, Chang-ying; Chang, Ji-wu; Zhu, Tie-hong

    2012-06-01

    To screen monoclonal antibodies to amylin from a constructed human phage antibody library and identify their antigenic specificity and combining activities. The heavy chain Fd fragment and light chain of human immunoglobulin genes were amplified from peripheral blood lymphocytes of healthy donors using RT-PCR, and then inserted into phagemid pComb3XSS to generate a human phage antibody library. The insertion of light chain or heavy chain Fd genes were identified by PCR after the digestion of Sac I, Xba I, Xho Iand Spe I. One of positive clones was analyzed by DNA sequencing. The specific anti-amylin clones were screened from antibody library against human amylin antigens and then the positive clones were determined by Phage-ELISA analysis. A Fab phage antibody library with 0.8×10(8); members was constructed with the efficacy of about 70%. DNA sequence analysis indicated V(H); gene belonged to V(H);3 gene family and V(λ); gene belonged to the V(λ); gene family. Using human amylin as panning antigen, specific anti-amylin Fab antibodies were enriched by screening the library for three times. Phage-ELISA assay showed the positive clones had very good specificity to amylin antigen. The successful construction of a phage antibody library and the identification of anti-amylin Fab antibodies provide a basis for further study and preparation of human anti-amylin antibodies.

  10. Cell-free synthesis of functional antibody fragments to provide a structural basis for antibody-antigen interaction.

    Directory of Open Access Journals (Sweden)

    Takayoshi Matsuda

    Full Text Available Growing numbers of therapeutic antibodies offer excellent treatment strategies for many diseases. Elucidation of the interaction between a potential therapeutic antibody and its target protein by structural analysis reveals the mechanism of action and offers useful information for developing rational antibody designs for improved affinity. Here, we developed a rapid, high-yield cell-free system using dialysis mode to synthesize antibody fragments for the structural analysis of antibody-antigen complexes. Optimal synthesis conditions of fragments (Fv and Fab of the anti-EGFR antibody 059-152 were rapidly determined in a day by using a 30-μl-scale unit. The concentration of supplemented disulfide isomerase, DsbC, was critical to obtaining soluble antibody fragments. The optimal conditions were directly applicable to a 9-ml-scale reaction, with linear scalable yields of more than 1 mg/ml. Analyses of purified 059-152-Fv and Fab showed that the cell-free synthesized antibody fragments were disulfide-bridged, with antigen binding activity comparable to that of clinical antibodies. Examination of the crystal structure of cell-free synthesized 059-152-Fv in complex with the extracellular domain of human EGFR revealed that the epitope of 059-152-Fv broadly covers the EGF binding surface on domain III, including residues that formed critical hydrogen bonds with EGF (Asp355EGFR, Gln384EGFR, H409EGFR, and Lys465EGFR, so that the antibody inhibited EGFR activation. We further demonstrated the application of the cell-free system to site-specific integration of non-natural amino acids for antibody engineering, which would expand the availability of therapeutic antibodies based on structural information and rational design. This cell-free system could be an ideal antibody-fragment production platform for functional and structural analysis of potential therapeutic antibodies and for engineered antibody development.

  11. Lyme disease antibody

    Science.gov (United States)

    ... JavaScript. The Lyme disease blood test looks for antibodies in the blood to the bacteria that causes ... needed. A laboratory specialist looks for Lyme disease antibodies in the blood sample using the ELISA test . ...

  12. Pesquisa de anticorpos para arbovírus no soro de residentes no povoado de Corte de Pedra, Valença, Bahia Research of antibodies to arbovirus in the serum of residentes of the village of Corte de Pedra, Valença, Bahia

    Directory of Open Access Journals (Sweden)

    José Tavares-Neto

    1986-12-01

    Full Text Available Foi realizado um estudo sorológico para verificação da presença de anticorpos para arbovírus em 288 indivíduos, residentes no povoado de Corte de Pedra, Valença, Bahia. Foram observados anticorpos inibidores de hemaglutinação e neutralizantes em 3.8% da amostra com a seguinte distribuição para flavivírus: Ilhéus (6, St. Louis (2, febre amarela (3, Rocio (1. Em um indivíduo, com residência anterior na Região Norte foram detectados anticorpos para Mayaro. Em 75 indivíduos testados aleatoriamente não foram observados anticorpos neutralizantes para o vesiculovírus Piry. Em outros 28 indivíduos, também selecionados ao acaso, anticorpos fixadores de complemento não foram detectados para os vírus dos grupos Changuinola, Phlebotomus e não grupados BE AR 408005 e BE AR 421710. Chama-se a atenção para a necessidade de estudos complementares para esclarecer a transmissão do vírus na área.A serological survey for research on antibodies to arbovirus was carried out on 288 residents to the rural zone of the village of Corte de Pedra, Valença, Bahia. It was observed that 3.8% of the sample population presented HI and N antibodies against Flaviviruses (Ilhéus 6. St, Louis 2, Yellow fever 3 and Rocio 1. One person, who had previously lived in the Amazon region, had antibodies to Mayaro. The authors were unable to detect either N antibodies for Piry virus in a random sample of 75 persons or CF antibodies against viruses of the Changuinola and Phlebotomus groups and ungrouped BE AR 408005 and BE AR 421710 in another random sample of 28 individuals. Complementary studies should be conducted in order to define the transmission of the different viruses in the area.

  13. Hybridization-based antibody cDNA recovery for the production of recombinant antibodies identified by repertoire sequencing.

    Science.gov (United States)

    Valdés-Alemán, Javier; Téllez-Sosa, Juan; Ovilla-Muñoz, Marbella; Godoy-Lozano, Elizabeth; Velázquez-Ramírez, Daniel; Valdovinos-Torres, Humberto; Gómez-Barreto, Rosa E; Martinez-Barnetche, Jesús

    2014-01-01

    High-throughput sequencing of the antibody repertoire is enabling a thorough analysis of B cell diversity and clonal selection, which may improve the novel antibody discovery process. Theoretically, an adequate bioinformatic analysis could allow identification of candidate antigen-specific antibodies, requiring their recombinant production for experimental validation of their specificity. Gene synthesis is commonly used for the generation of recombinant antibodies identified in silico. Novel strategies that bypass gene synthesis could offer more accessible antibody identification and validation alternatives. We developed a hybridization-based recovery strategy that targets the complementarity-determining region 3 (CDRH3) for the enrichment of cDNA of candidate antigen-specific antibody sequences. Ten clonal groups of interest were identified through bioinformatic analysis of the heavy chain antibody repertoire of mice immunized with hen egg white lysozyme (HEL). cDNA from eight of the targeted clonal groups was recovered efficiently, leading to the generation of recombinant antibodies. One representative heavy chain sequence from each clonal group recovered was paired with previously reported anti-HEL light chains to generate full antibodies, later tested for HEL-binding capacity. The recovery process proposed represents a simple and scalable molecular strategy that could enhance antibody identification and specificity assessment, enabling a more cost-efficient generation of recombinant antibodies.

  14. Short-term efficacy of intravitreal conbercept in treatment-naive patients with polypoidal choroidal vasculopathy

    Directory of Open Access Journals (Sweden)

    Peng Y

    2018-02-01

    Full Text Available Yuting Peng, Xiongze Zhang, Miaoling Li, Bing Liu, Lan Mi, Chengguo Zuo, Feng Wen State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China Introduction: To evaluate the functional and morphological outcomes of intravitreal conbercept monotherapy in patients with polypoidal choroidal vasculopathy (PCV. Materials and methods: In this retrospective, observational case series study, we reviewed medical records of 48 eyes (48 patients with naive PCV that were treated with a series of 3 monthly intravitreal injections of 0.5 mg of conbercept followed by as-needed injections (3+pro re nata. All patients completed at least 6 months of monthly follow-up. Changes in the best-corrected visual acuity, optical coherence tomography, and indocyanine green angiography were retrospectively evaluated. Results: At 6 months, the mean best-corrected visual acuity significantly improved from 0.89±0.35 (20/160 in Snellen equivalent at baseline to 0.58±0.26 (Snellen equivalent of 20/80; P<0.001, and 60.42% (29/48 of eyes had an improvement of three lines of vision; the mean central retinal thickness significantly decreased from 333.56±171.04 µm at baseline to 187.65±54.46 µm (P<0.001, and 93.75% (45/48 achieved a dry macula. At 3 months, 6 of 32 eyes (18.75% showed partial regression of branching vascular network, 14 of 32 (43.75% patients showed complete resolution of polyps. The mean number of injections was 3.4±0.9 through 6 months. No conbercept-related systemic or ocular adverse effects were observed. Conclusion: Intravitreal injection of conbercept using “3+pro re nata” regimen significantly improved visual acuity and anatomical outcomes in treatment-naive patients with PCV. Keywords: conbercept, intravitreal injection, PCV, short-term efficacy, “3+PRN”

  15. Antibody or Antibody Fragments: Implications for Molecular Imaging and Targeted Therapy of Solid Tumors

    Directory of Open Access Journals (Sweden)

    Katerina T. Xenaki

    2017-10-01

    Full Text Available The use of antibody-based therapeutics has proven very promising for clinical applications in cancer patients, with multiple examples of antibodies and antibody–drug conjugates successfully applied for the treatment of solid tumors and lymphomas. Given reported recurrence rates, improvements are clearly still necessary. A major factor limiting the efficacy of antibody-targeted cancer therapies may be the incomplete penetration of the antibody or antibody–drug conjugate into the tumor. Incomplete tumor penetration also affects the outcome of molecular imaging, when using such targeting agents. From the injection site until they arrive inside the tumor, targeting molecules are faced with several barriers that impact intratumoral distribution. The primary means of antibody transport inside tumors is based on diffusion. The diffusive penetration inside the tumor is influenced by both antibody properties, such as size and binding affinity, as well as tumor properties, such as microenvironment, vascularization, and targeted antigen availability. Engineering smaller antibody fragments has shown to improve the rate of tumor uptake and intratumoral distribution. However, it is often accompanied by more rapid clearance from the body and in several cases also by inherent destabilization and reduction of the binding affinity of the antibody. In this perspective, we discuss different cancer targeting approaches based on antibodies or their fragments. We carefully consider how their size and binding properties influence their intratumoral uptake and distribution, and how this may affect cancer imaging and therapy of solid tumors.

  16. Anti-transferrin receptor antibody and antibody-drug conjugates cross the blood-brain barrier

    International Nuclear Information System (INIS)

    Friden, P.M.; Walus, L.R.; Musso, G.F.; Taylor, M.A.; Malfroy, B.; Starzyk, R.M.

    1991-01-01

    Delivery of nonlipophilic drugs to the brain is hindered by the tightly apposed capillary endothelial cells that make up the blood-brain barrier. The authors have examined the ability of a monoclonal antibody (OX-26), which recognizes the rat transferrin receptor, to function as a carrier for the delivery of drugs across the blood-brain barrier. This antibody, which was previously shown to bind preferentially to capillary endothelial cells in the brain after intravenous administration, labels the entire cerebrovascular bed in a dose-dependent manner. The initially uniform labeling of brain capillaries becomes extremely punctate ∼ 4 hr after injection, suggesting a time-dependent sequestering of the antibody. Capillary-depletion experiments, in which the brain is separated into capillary and parenchymal fractions, show a time-dependent migration of radiolabeled antibody from the capillaries into the brain parenchyma, which is consistent with the transcytosis of compounds across the blood-brain barrier. Antibody-methotrexate conjugates were tested in vivo to assess the carrier ability of this antibody. Immunohistochemical staining for either component of an OX-26-methotrexate conjugate revealed patterns of cerebrovascular labeling identical to those observed with the unaltered antibody. Accumulation of radiolabeled methotrexate in the brain parenchyma is greatly enhanced when the drug is conjugated to OX-26

  17. Persistence of bactericidal antibodies following early infant vaccination with a serogroup B meningococcal vaccine and immunogenicity of a preschool booster dose.

    Science.gov (United States)

    Snape, Matthew D; Saroey, Praveen; John, Tessa M; Robinson, Hannah; Kelly, Sarah; Gossger, Nicoletta; Yu, Ly-Mee; Wang, Huajun; Toneatto, Daniela; Dull, Peter M; Pollard, Andrew J

    2013-10-15

    The multicomponent serogroup B meningococcal (4CMenB) vaccine was recently licensed for use in Europe. There are currently no data on the persistence of bactericidal antibodies induced by use of this vaccine in infants. Our objective was to evaluate serogroup B-specific bactericidal antibodies in children aged 40-44 months previously vaccinated at 2, 4, 6 and 12 months of age. Participants given 4 doses of 4CMenB as infants received a fifth dose of the vaccine at 40-44 months of age. Age-matched participants who were MenB vaccine-naive received 4CMenB and formed the control group. We evaluated human complement serum bactericidal activity (hSBA) titres at baseline and 1 month after each dose of 4CMenB. Before a booster dose at enrolment, 41%-76% of 17 participants previously vaccinated with 4CMenB in infancy had hSBA titres of 4 or greater against 4 reference strains. Before vaccination in the control group (n = 40) these proportions were similar for strains 44/76-SL (63%) and M10713 (68%) but low for strains NZ98/254 (0%) and 5/99 (3%). A booster dose in the 4CMenB-primed participants generated greater increases in hSBA titres than in controls. As has been observed with other meningococcal vaccines, bactericidal antibodies waned after vaccination with 4CMenB administered according to an approved infant vaccination schedule of 2, 4, 6 and 12 months of age, but there was an anamnestic response to a booster dose at 40-44 months of age. If 4CMenB were introduced into routine vaccination schedules, assessment of the need for a booster dose would require data on the impact of these declining titres on vaccine effectiveness. ClinicalTrials.gov, no. NCT01027351.

  18. Randomized, Double-Blind, Phase III Trial of Ipilimumab Versus Placebo in Asymptomatic or Minimally Symptomatic Patients With Metastatic Chemotherapy-Naive Castration-Resistant Prostate Cancer

    DEFF Research Database (Denmark)

    Beer, Tomasz M; Kwon, Eugene D; Drake, Charles G

    2017-01-01

    Purpose Ipilimumab increases antitumor T-cell responses by binding to cytotoxic T-lymphocyte antigen 4. We evaluated treatment with ipilimumab in asymptomatic or minimally symptomatic patients with chemotherapy-naive metastatic castration-resistant prostate cancer without visceral metastases. Pat...

  19. KADAR ANTIBODI-TIROPEROKSIDASE DAN ANTIBODI-TIROGLOBULIN PADA WANITA USIA SUBUR DI DAERAH ENDEMlS GAKI

    Directory of Open Access Journals (Sweden)

    Agus Wibowo

    2012-10-01

    Full Text Available Background: Thyroid hormones play a critical role in human. Disorders of the thyroid gland result primary from autoimmune processes that either stimulate the over production of thyroid hormones (hyperthyroid or causes glandular destruction and hormones deficiency (hypothyroid. Autoimmune Thyroid Disease (AITD a common organ specific autoimmune disorder is seen mostly in women. AITD are complex disease that are caused by an interaction between susceptibility genes and environmental trigger such dietary iodine. The development of antibodies to Thyroid peroxidase (TPO and Thyroglobulin (TG is the main hall mark of AITD. Method: 'Thirty respondents from were analyzed. The blood were collected for TSH, FreeT4, Tyroglobulin Antibody and Tyroperoxidase Antibody analyzed and DNA isolation. Circulating TSH, FreeT4, autoantibodies to TPO and TG are measured by ELISA. Result: 50% respondent in normal thyroid hormones and 50% in hypothyroid and hyperthyroid status. TPO antibodies  and thyroglobulin antibodies found in all of respondent with thyroid disorder. Conclusion: Antibodies to TPO and TG is seen in respondent with thyroid disorder   Keywords: AITD, TSH, FreeT4, TPO antibodies, TG antibodies.

  20. Antibody engineering using phage display with a coiled-coil heterodimeric Fv antibody fragment.

    Directory of Open Access Journals (Sweden)

    Xinwei Wang

    Full Text Available A Fab-like antibody binding unit, ccFv, in which a pair of heterodimeric coiled-coil domains was fused to V(H and V(L for Fv stabilization, was constructed for an anti-VEGF antibody. The anti-VEGF ccFv showed the same binding affinity as scFv but significantly improved stability and phage display level. Furthermore, phage display libraries in the ccFv format were constructed for humanization and affinity maturation of the anti-VEGF antibody. A panel of V(H frameworks and V(H-CDR3 variants, with a significant improvement in affinity and expressibility in both E. coli and yeast systems, was isolated from the ccFv phage libraries. These results demonstrate the potential application of the ccFv antibody format in antibody engineering.

  1. Chemokine (C-C motif) receptor 5-using envelopes predominate in dual/mixed-tropic HIV from the plasma of drug-naive individuals.

    Science.gov (United States)

    Irlbeck, David M; Amrine-Madsen, Heather; Kitrinos, Kathryn M; Labranche, Celia C; Demarest, James F

    2008-07-31

    HIV-1 utilizes CD4 and either chemokine (C-C motif) receptor 5 (CCR5) or chemokine (C-X-C motif) receptor 4 (CXCR4) to gain entry into host cells. Small molecule CCR5 antagonists are currently being developed for the treatment of HIV-1 infection. Because HIV-1 may also use CXCR4 for entry, the use of CCR5 entry inhibitors is controversial for patients harboring CCR5-using and CXCR4-using (dual/mixed-tropic) viruses. The goal of the present study was to determine the proportion of CCR5-tropic and CXCR4-tropic viruses in dual/mixed-tropic virus isolates from drug-naïve patients and the phenotypic and genotypic relationships of viruses that use CCR5 or CXCR4 or both. Fourteen antiretroviral-naive HIV-1-infected patients were identified as having population coreceptor tropism readout of dual/mixed-tropic viruses. Intrapatient comparisons of coreceptor tropism and genotype of env clones were conducted on plasma virus from each patient. Population HIV-1 envelope tropism and susceptibility to the CCR5 entry inhibitor, aplaviroc, were performed using the Monogram Biosciences Trofile Assay. Twelve env clones from each patient were analyzed for coreceptor tropism, aplaviroc sensitivity, genotype, and intrapatient phylogenetic relationships. Viral populations from antiretroviral-naive patients with dual/mixed-tropic virus are composed primarily of CCR5-tropic env clones mixed with those that use both coreceptors (R5X4-tropic) and, occasionally, CXCR4-tropic env clones. Interestingly, the efficiency of CXCR4 use by R5X4-tropic env clones varied with their genetic relationships to CCR5-tropic env clones from the same patient. These data show that the majority of viruses in these dual/mixed-tropic populations use CCR5 and suggest that antiretroviral-naive patients may benefit from combination therapy that includes CCR5 entry inhibitors.

  2. Tabhu: tools for antibody humanization

    DEFF Research Database (Denmark)

    Olimpieri, Pier Paolo; Marcatili, Paolo; Tramontano, Anna

    2015-01-01

    Antibodies are rapidly becoming essential tools in the clinical practice, given their ability to recognize their cognate antigens with high specificity and affinity, and a high yield at reasonable costs in model animals. Unfortunately, when administered to human patients, xenogeneic antibodies can...... elicit unwanted and dangerous immunogenic responses. Antibody humanization methods are designed to produce molecules with a better safety profile still maintaining their ability to bind the antigen. This can be accomplished by grafting the non-human regions determining the antigen specificity...... and time-consuming experiments. Here we present tools for antibody humanization (Tabhu) a web server for antibody humanization. Tabhu includes tools for human template selection, grafting, back-mutation evaluation, antibody modelling and structural analysis, helping the user in all the critical steps...

  3. Antibody or Antibody Fragments : Implications for Molecular Imaging and Targeted Therapy of Solid Tumors

    NARCIS (Netherlands)

    Xenaki, Katerina T; Oliveira, Sabrina; van Bergen En Henegouwen, Paul M P

    2017-01-01

    The use of antibody-based therapeutics has proven very promising for clinical applications in cancer patients, with multiple examples of antibodies and antibody-drug conjugates successfully applied for the treatment of solid tumors and lymphomas. Given reported recurrence rates, improvements are

  4. Evidence that radio-sensitive cells are central to skin-phase protective immunity in CBA/Ca mice vaccinated with radiation-attenuated cercariae of Schistosoma mansoni as well as in naive mice protected with vaccine serum

    International Nuclear Information System (INIS)

    Delgado, V.S.; McLaren, D.J.

    1990-01-01

    Naive CBA/Ca mice and CBA/ca mice vaccinated 4 weeks previously with radiation-attenuated cercariae of Schistosoma mansoni were subjected to 550 rad of whole body (gamma) irradiation and then challenged 3 days later with normal cercariae. The perfusion recovery data showed that this procedure reduced the primary worm burden in naive mice by 22% and the challence worm burden in vaccinated mice by 82%. Irradiation also ablated the peripheral blood leucocytes of both mouse groups by 90-100% at the time of challenge. Histological data revealed that such treatment caused a dramatic change in number, size and leucocyte composition of cutaneous inflammatory skin reactions that characterize challenged vacccinated mice and are known to entrap invading larvae; cutaneous eosinophils were preferentially abolished by this treatment. Polyvaccine mouse serum that conferred protection passively upon naive recipient mice, failed to protect naive/irradiated mice when administered by the same protocol. Distraction of macrophages by treatment of mice with silica did not affect the establishment of a primary worm burden and reduced the protection exhibited by vaccinated mice by only 16%. These data indicade that radio-sensitive cells are important to both innate and specific acquired resistance in this mouse model and that macrophages contribute only marginally to the expression of vaccine immunity. (author)

  5. What Is Antiphospholipid Antibody Syndrome?

    Science.gov (United States)

    ... Back To Health Topics / Antiphospholipid Antibody Syndrome Antiphospholipid Antibody Syndrome Also known as What Is Antiphospholipid (AN-te-fos-fo-LIP-id) antibody syndrome (APS) is an autoimmune disorder. Autoimmune disorders ...

  6. Antibody engineering: methods and protocols

    National Research Council Canada - National Science Library

    Chames, Patrick

    2012-01-01

    "Antibody Engineering: Methods and Protocols, Second Edition was compiled to give complete and easy access to a variety of antibody engineering techniques, starting from the creation of antibody repertoires and efficient...

  7. Dual role of miR-21 in CD4+ T-cells: activation-induced miR-21 supports survival of memory T-cells and regulates CCR7 expression in naive T-cells.

    Directory of Open Access Journals (Sweden)

    Katarzyna Smigielska-Czepiel

    Full Text Available Immune cell-type specific miRNA expression patterns have been described but the detailed role of single miRNAs in the function of T-cells remains largely unknown. We investigated the role of miR-21 in the function of primary human CD4+ T-cells. MiR-21 is substantially expressed in T-cells with a memory phenotype, and is robustly upregulated upon αCD3/CD28 activation of both naive and memory T-cells. By inhibiting the endogenous miR-21 function in activated naive and memory T-cells, we showed that miR-21 regulates fundamentally different aspects of T-cell biology, depending on the differentiation status of the T-cell. Stable inhibition of miR-21 function in activated memory T-cells led to growth disadvantage and apoptosis, indicating that the survival of memory T-cells depends on miR-21 function. In contrast, stable inhibition of miR-21 function in activated naive T-cells did not result in growth disadvantage, but led to a significant induction of CCR7 protein expression. Direct interaction between CCR7 and miR-21 was confirmed in a dual luciferase reporter assay. Our data provide evidence for a dual role of miR-21 in CD4+ T cells; Regulation of T-cell survival is confined to activated memory T-cells, while modulation of potential homing properties, through downregulation of CCR7 protein expression, is observed in activated naive T-cells.

  8. Designing two-in-one antibodies.

    Science.gov (United States)

    Valladares, Ignacio Garcia; Espinoza, Luis R

    2009-09-01

    Evaluation of: Bostrom J, Shang-Fan Y, Kan D et al.: Variants of the antibody Herceptin that interact with HER2 and VEGF at the antigen binding site. Science 323, 1610-1614 (2009). The longstanding held notion that one antibody equals one antigen and, hence, one function has been challenged in recent years. Improved technology in antibody production, especially the accumulation of sequence data of immunoglobulin genes and the advent of PCR have made it possible to clone antibody gene repertoires. The current paper provides further challenge to the notion of one antibody = one antigen by developing 'two-in-one' antibodies with an antigen-binding site that binds two distinct proteins with high affinity. A therapeutic variant antibody of Herceptin (Genentech, CA, USA) was isolated that binds the human EGF receptor (HER)2 and also to VEGF. This development may represent a breakthrough discovery and may have significant implications in the therapy of malignant, infectious, allergic and autoimmune disorders.

  9. Clearance of 131I-labeled murine monoclonal antibody from patients' blood by intravenous human anti-murine immunoglobulin antibody

    International Nuclear Information System (INIS)

    Stewart, J.S.; Sivolapenko, G.B.; Hird, V.; Davies, K.A.; Walport, M.; Ritter, M.A.; Epenetos, A.A.

    1990-01-01

    Five patients treated with intraperitoneal 131I-labeled mouse monoclonal antibody for ovarian cancer also received i.v. exogenous polyclonal human anti-murine immunoglobulin antibody. The pharmacokinetics of 131I-labeled monoclonal antibody in these patients were compared with those of 28 other patients receiving i.p.-radiolabeled monoclonal antibody for the first time without exogenous human anti-murine immunoglobulin, and who had no preexisting endogenous human anti-murine immunoglobulin antibody. Patients receiving i.v. human anti-murine immunoglobulin antibody demonstrated a rapid clearance of 131I-labeled monoclonal antibody from their circulation. The (mean) maximum 131I blood content was 11.4% of the injected activity in patients receiving human anti-murine immunoglobulin antibody compared to 23.3% in patients not given human anti-murine immunoglobulin antibody. Intravenous human anti-murine immunoglobulin antibody decreased the radiation dose to bone marrow (from 131I-labeled monoclonal antibody in the vascular compartment) 4-fold. Following the injection of human anti-murine immunoglobulin antibody, 131I-monoclonal/human anti-murine immunoglobulin antibody immune complexes were rapidly transported to the liver. Antibody dehalogenation in the liver was rapid, with 87% of the injected 131I excreted in 5 days. Despite the efficient hepatic uptake of immune complexes, dehalogenation of monoclonal antibody was so rapid that the radiation dose to liver parenchyma from circulating 131I was decreased 4-fold rather than increased. All patients developed endogenous human anti-murine immunoglobulin antibody 2 to 3 weeks after treatment

  10. Lack of antibodies to NMDAR or VGKC-complex in GAD and cardiolipin antibody-positive refractory epilepsy.

    Science.gov (United States)

    Liimatainen, Suvi; Peltola, Jukka; Hietaharju, Aki; Sabater, Lidia; Lang, Bethan

    2014-03-01

    Over the last few years autoantibodies against neuronal proteins have been identified in several forms of autoimmune encephalitis and epilepsy. NMDA receptor (NMDAR) and voltage gated potassium channel (VGKC) complex antibodies are mainly associated with limbic encephalitis (LE) whereas glutamic acid decarboxylase antibodies (GADA) and anticardiolipin (ACL) antibodies are more commonly detected in patients with chronic epilepsy. Clinical features vary between these antibodies suggesting the specificity of different neuronal antibodies in seizures. Serum samples of 14 GADA positive and 24 ACL positive patients with refractory epilepsy were analyzed for the presence of VGKC or NMDAR antibodies. No positive VGKC or NMDAR antibodies were found in these patients. The results confirm the different significance of these neuronal antibodies in seizure disorders. Different autoantibodies have different significance in seizures and probably have different pathophysiological mechanisms of actions. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. An efficient method for isolating antibody fragments against small peptides by antibody phage display

    DEFF Research Database (Denmark)

    Duan, Zhi; Siegumfeldt, Henrik

    2010-01-01

    We generated monoclonal scFv (single chain variable fragment) antibodies from an antibody phage display library towards three small synthetic peptides derived from the sequence of s1-casein. Key difficulties for selection of scFv-phages against small peptides were addressed. Small peptides do....... The scFvs were sequenced and characterized, and specificity was characterized by ELISA. The methods developed in this study are universally applicable for antibody phage display to efficiently produce antibody fragments against small peptides....

  12. Immunogenicity of anti-tumor necrosis factor antibodies-toward improved methods of anti-antibody measurement.

    Science.gov (United States)

    Aarden, Lucien; Ruuls, Sigrid R; Wolbink, Gertjan

    2008-08-01

    To date, millions of people have been treated with therapeutic monoclonal antibodies (TmAbs) for various indications. It is becoming increasingly clear that TmAbs can be immunogenic, which may reduce efficacy or induce adverse effects. Over the years, the importance of antibody formation has been questioned and sometimes minimized, as few antibody responses to TmAbs (HACA or HAHA) were reported. However, the methods to detect and quantify such antibodies used in the past have been problematic. Only recently, methods have been developed that have adequate sensitivity and are not seriously disturbed by false-positive reactions caused by rheumatoid factors, natural antibodies to Fab or F(ab')2 fragments, or Fc interactions of IgG4. The large number of treated patients, in combination with these new assays, presents a unique opportunity to study the anti-antibody immune response in man, possibly allowing us to manipulate immunogenicity in the future.

  13. High Prevalence of HIV Low Abundance Drug-Resistant Variants in a Treatment-Naive Population in North Rift Kenya.

    Science.gov (United States)

    Cheriro, Winfrida; Kiptoo, Michael; Kikuvi, Gideon; Mining, Simeon; Emonyi, Wilfred; Songok, Elijah

    2015-12-01

    The advent of antiretroviral treatment (ART) has resulted in a dramatic reduction in AIDS-related morbidity and mortality. However, the emergence and spread of antiretroviral drug resistance (DR) threaten to negatively impact treatment regimens and compromise efforts to control the epidemic. It is recommended that surveillance of drug resistance occur in conjunction with scale-up efforts to ensure that appropriate first-line therapy is offered relative to the resistance that exists. However, standard resistance testing methods used in Sub-Saharan Africa rely on techniques that do not include low abundance DR variants (LADRVs) that have been documented to contribute to treatment failure. The use of next generation sequencing (NGS) has been shown to be more sensitive to LADRVS. We have carried out a preliminary investigation using NGS to determine the prevalence of LDRVS among a drug-naive population in North Rift Kenya. Antiretroviral-naive patients attending a care clinic in North Rift Kenya were requested to provide and with consent provided blood samples for DR analysis. DNA was extracted and amplified and nested PCR was conducted on the pol RT region using primers tagged with multiplex identifiers (MID). Resulting PCR amplicons were purified, quantified, and pyrosequenced using a GS FLX Titanium PicoTiterPlate (Roche). Valid pyrosequencing reads were aligned with HXB-2 and the frequency and distribution of nucleotide and amino acid changes were determined using an in-house Perl script. DR mutations were identified using the IAS-USA HIV DR mutation database. Sixty samples were successfully sequenced of which 26 were subtype A, 9 were subtype D, 2 were subtype C, and the remaining were recombinants. Forty-six (76.6%) had at least one drug resistance mutation, with 25 (41.6%) indicated as major and the remaining 21 (35%) indicated as minor. The most prevalent mutation was NRTI position K219Q/R (11/46, 24%) followed by NRTI M184V (5/46, 11%) and NNRTI K103N (4/46, 9

  14. Generalized Platform for Antibody Detection using the Antibody Catalyzed Water Oxidation Pathway

    OpenAIRE

    Welch, M. Elizabeth; Ritzert, Nicole L.; Chen, Hongjun; Smith, Norah L.; Tague, Michele E.; Xu, Youyong; Baird, Barbara A.; Abru?a, H?ctor D.; Ober, Christopher K.

    2014-01-01

    Infectious diseases, such as influenza, present a prominent global problem including the constant threat of pandemics that initiate in avian or other species and then pass to humans. We report a new sensor that can be specifically functionalized to detect antibodies associated with a wide range of infectious diseases in multiple species. This biosensor is based on electrochemical detection of hydrogen peroxide generated through the intrinsic catalytic activity of all antibodies: the antibody ...

  15. Microangiopathic antiphospholipid antibody syndrome due to anti-phosphatidylserine/prothrombin complex IgM antibody.

    Science.gov (United States)

    Senda, Yumi; Ohta, Kazuhide; Yokoyama, Tadafumi; Shimizu, Masaki; Furuichi, Kengo; Wada, Takashi; Yachie, Akihiro

    2017-03-01

    Herein we describe a case of microangiopathic antiphospholipid syndrome (MAPS) due to anti-phosphatidylserine/prothrombin complex (aPS/PT) IgM antibody successfully treated with rituximab. A significant correlation was observed between the clinical course and the aPS/PT IgM antibody titer, which can rise earlier before the appearance of clinical symptoms. Rituximab can be safely and effectively used for MAPS. Although detection of only aPS/PT IgM antibody is rare, aPS/PT IgM antibody might be associated with the pathogenesis of MAPS and might be a useful marker of disease activity. © 2017 Japan Pediatric Society.

  16. Lichen planus, liver kidney microsomal (LKM1) antibodies and hepatitis C virus antibodies.

    Science.gov (United States)

    Divano, M C; Parodi, A; Rebora, A

    1992-01-01

    No anti-liver kidney microsomal (LKM1) antibodies were detected in 46 patients with LP, 16 of whom had also a chronic liver disease (CLD). In contrast, anti-hepatitis C virus (HCV) antibodies were found in 10% of patients with LP and in 50% of those with LP and CLD. Anti-HCV antibodies may be considered as a false-positive reaction in 56% of cases, especially when anti-LKM1 antibodies are present. Our findings do not support such a hypothesis, but suggest that CLD in LP patients is, at least in Italy, mostly a postviral chronic active hepatitis.

  17. [Antibody therapy for Alzheimer's disease].

    Science.gov (United States)

    Tabira, Takeshi; Matsumoto, Shin-Ei; Jin, Haifeng

    2011-11-01

    In order to avoid Abeta-induced autoimmune encephalitis, several monoclonal and polyclonal antibodies are in clinical trials. These are bapineuzumab, solanezumab, ponezumab, gantenerumab, BAN2401, gammaguard and octagam. Since each antibody has a different antigen epitope of Abeta, anti-amyloid activities are different. It is unknown which antibody is effective for Alzheimer disease, and we must wait for the result of clinical trials. Some patients who developed tissue amyloid plaque immuno-reactive (TAPIR) antibody showed slower decline after AN-1792 vaccination. We developed TAPIR-like monoclonal antibody, which was found to react with Abeta oligomers preferentially.

  18. Anti-idiotypic antibodies to poliovirus antibodies in commercial immunoglubulin preparations, human serum and milk.

    NARCIS (Netherlands)

    M. Hahn-Zoric; B. Carlsson; S. Jeansson; H.P. Ekre; A.D.M.E. Osterhaus (Albert); D. Roberton; L.A. Hanson

    1993-01-01

    textabstractOur previous studies have suggested that fetal antibody production can be induced by maternal antiidiotypic antibodies transferred to the fetus via the placenta. We tested commercial Ig, sera, and milk for the presence of anti-idiotypic antibodies to poliovirus type 1, using affinity

  19. The eukaryotic translation initiation factor 3 subunit L protein interacts with Flavivirus NS5 and may modulate yellow fever virus replication.

    Science.gov (United States)

    Morais, Ana Ts; Terzian, Ana Cb; Duarte, Danilo Vb; Bronzoni, Roberta Vm; Madrid, Maria Cfs; Gavioli, Arieli F; Gil, Laura Hvg; Oliveira, Amanda G; Zanelli, Cleslei F; Valentini, Sandro R; Rahal, Paula; Nogueira, Mauricio L

    2013-06-22

    Yellow fever virus (YFV) belongs to the Flavivirus genus and causes an important disease. An alarming resurgence of viral circulation and the expansion of YFV-endemic zones have been detected in Africa and South America in recent years. NS5 is a viral protein that contains methyltransferase and RNA-dependent RNA polymerase (RdRp) domains, which are essential for viral replication, and the interactions between NS5 and cellular proteins have been studied to better understand viral replication. The aim of this study was to characterize the interaction of the NS5 protein with eukaryotic translation initiation factor 3 subunit L (eIF3L) and to evaluate the role of eIF3L in yellow fever replication. To identify interactions of YFV NS5 with cellular proteins, we performed a two-hybrid screen using the YFV NS5 RdRp domain as bait with a human cDNA library, and RNApol deletion mutants were generated and analyzed using the two-hybrid system for mapping the interactions. The RNApol region involved was segmented into three fragments and analyzed using an eIF3L-expressing yeast strain. To map the NS5 residues that are critical for the interactions, we performed site-direct mutagenesis in segment 3 of the interaction domain (ID) and confirmed the interaction using in vitro assays and in vivo coimmunoprecipitation. The significance of eIF3L for YFV replication was investigated using eIF3L overexpression and RNA interference. In this work, we describe and characterize the interaction of NS5 with the translation factor eIF3L. The interaction between NS5 and eIF3L was confirmed using in vitro binding and in vivo coimmunoprecipitation assays. This interaction occurs at a region (the interaction domain of the RNApol domain) that is conserved in several flaviviruses and that is, therefore, likely to be relevant to the genus. eIF3L overexpression and plaque reduction assays showed a slight effect on YFV replication, indicating that the interaction of eIF3L with YFV NS5 may play a role

  20. 9 CFR 113.452 - Erysipelothrix Rhusiopathiae Antibody.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Erysipelothrix Rhusiopathiae Antibody... REQUIREMENTS Antibody Products § 113.452 Erysipelothrix Rhusiopathiae Antibody. Erysipelothrix Rhusiopathiae Antibody is a specific antibody product containing antibodies directed against one or more somatic antigens...

  1. Future of antibody purification.

    Science.gov (United States)

    Low, Duncan; O'Leary, Rhona; Pujar, Narahari S

    2007-03-15

    Antibody purification seems to be safely ensconced in a platform, now well-established by way of multiple commercialized antibody processes. However, natural evolution compels us to peer into the future. This is driven not only by a large, projected increase in the number of antibody therapies, but also by dramatic improvements in upstream productivity, and process economics. Although disruptive technologies have yet escaped downstream processes, evolution of the so-called platform is already evident in antibody processes in late-stage development. Here we perform a wide survey of technologies that are competing to be part of that platform, and provide our [inherently dangerous] assessment of those that have the most promise.

  2. [Screening serum response special antibodies of U251 cell line from surface display phage antibody library].

    Science.gov (United States)

    Yu, Min; Tan, De-Yong; Qian, Wei; Lai, Jian-Hua; Sun, Gui-Lin

    2004-05-01

    U251 cell is a sensitive cell line to serum, which stops at G0 phase of cell cycle in no-serum medium, and recovers growth when the serum is added into no-serum medium. The cell can express corresponding proteins in different phase of cell cycle. Therefore it is very signification for the study of cell cycle regulation mechanism that explores these proteins. In this paper, the mouse antibody phage display library was added into the bottle in which the serum starvation U251 cells had been cultured, and the special antibody phages were absorbed. Then the absorbed antibody phages were amplified by adding E. coli TG1 and helper phage M13K07. Amplified antibody phages were added into bottle in which the serum cultured cell after serum starvation (follow named as serum recovered cells) were incubated, so that the cell absorbed the no-special antibody phages for the serum starvation cell and the special antibody phages were in supernatant. The remaining no-special antibody phages in the supernatant were discarded by repeating above program 3-4 times. The pure special antibody phages were gotten, and amplified by adding the host cell E. coli TG1 and helper phage M13K07. Then the host bacterium infected special antibody phage was spread on the plate medium with ampicillin, and the monoclonal antibody phages were gotten. Using same as above program, the monoclonal antibody phages absorbed specially for serum recovered U251 cells were obtained when the serum recovered cells instead of serum starvation cells and serum starvation cells instead of serum recovered cells. In this study, ninety-six positive monoclonal antibody phages that absorbed specially the serum starvation cells and eighty-two positive monoclonal antibody phages that absorbed specially the serum recovered cells were obtained. By using cell immunochemistry assay, two special signification antibodies were obtained. one (No.11) was the strong response in serum starvation cells, the other (No.2) was the strong

  3. Bispecific antibodies targeting human CD73

    DEFF Research Database (Denmark)

    2017-01-01

    The present invention relates to a bispecific antibody targeting CD73. In particular, the present invention relates to a bispecific antibody targeting different epitopes on CD73 or a bispecific antibody targeting an epitope on CD73 and an epitope on a different antigen.......The present invention relates to a bispecific antibody targeting CD73. In particular, the present invention relates to a bispecific antibody targeting different epitopes on CD73 or a bispecific antibody targeting an epitope on CD73 and an epitope on a different antigen....

  4. The production of antibody fragments and antibody fusion proteins by yeasts and filamentous fungi

    NARCIS (Netherlands)

    Joosten, V.; Lokman, C.; Hondel, C.A.M.J.J. van den; Punt, P.J.

    2003-01-01

    In this review we will focus on the current status and views concerning the production of antibody fragments and antibody fusion proteins by yeasts and filamentous fungi. We will focus on single-chain antibody fragment production (scFv and VHH) by these lower eukaryotes and the possible applications

  5. Zika virus infection in a traveller returning from the Maldives, June 2015.

    Science.gov (United States)

    Korhonen, Essi Marjana; Huhtamo, Eili; Smura, Teemu; Kallio-Kokko, Hannimari; Raassina, Markku; Vapalahti, Olli

    2016-01-01

    We report a Zika virus (ZIKV) infection in a patient with fever and rash after returning to Finland from Maldives, June 2015. The patient had dengue virus (DENV) IgG and IgM antibodies but pan-flavivirus RT-PCR and subsequent sequencing showed presence of ZIKV RNA in urine. Recent association of ZIKV with microcephaly highlights the need for laboratory differentiation of ZIKV from DENV infection and the circulation of ZIKV in areas outside its currently known distribution range.

  6. Antibodies from plants for bionanomaterials

    OpenAIRE

    Edgue, G.; Twyman, R.M.; Beiss, V.; Fischer, R.; Sack, M.

    2017-01-01

    Antibodies are produced as part of the vertebrate adaptive immune response and are not naturally made by plants. However, antibody DNA sequences can be introduced into plants, and together with laboratory technologies that allow the design of antibodies recognizing any conceivable molecular structure, plants can be used as green factories' to produce any antibody at all. The advent of plant-based transient expression systems in particular allows the rapid, convenient, and safe production of a...

  7. Cytopenias among ART-naive patients with advanced HIV disease on enrolment to care and treatment services at a tertiary hospital in Tanzania: A cross-sectional study.

    Science.gov (United States)

    Gunda, Daniel W; Godfrey, Kahamba G; Kilonzo, Semvua B; Mpondo, Bonaventura C

    2017-03-01

    HIV/AIDS causes high morbidity and mortality through both immunosuppression and complications not directly related to immunosuppression. Haematological abnormalities, including various cytopenias, occur commonly in HIV through immune and non-immune pathways. Though these complications could potentially cause serious clinical implications, published literature on the magnitude of this problem and its associated factors in Tanzania is scarce. This study aimed at determining the prevalence and risk factors of HIV-associated cytopenias among ART-naive patients enrolling for care and treatment services at Bugando Care and Treatment Centre (CTC) in Mwanza, Tanzania. This was a cross-sectional clinic-based study done between March 2015 and February 2016, involving all antiretroviral therapy (ART)-naive adult HIV-positive patients enrolling for care and treatment services at Bugando CTC. Patients younger than 18 years and those with missing data were excluded. Data were analysed using Stata version 11 to determine the prevalence and risk factors of cytopenias. A total of 1205 ART-naive patients were included. Median age was 41 years (interquartile range [IQR] 32 to 48). Most participants were female (n = 789; 65.6%), with a female-to-male ratio of 2:1. The median baseline CD4 count was 200 cells/µL (IQR 113 to 439). About half (49%) of the study participants had baseline CD4 counts less than 200 cells/µL. Anaemia, leucopenia, and thrombocytopenia were found in 704 (58.4%), 285 (23.6%), and 174 (14.4%) participants, respectively, and these were strongly associated with advanced HIV infection. The magnitude of cytopenias is high among ART-naive HIV-positive adults, and cytopenias are more marked with advanced HIV infection. Early diagnosis of HIV and timely initiation of ART could potentially reduce the number of people living with advanced HIV disease and its associated complications, including the cytopenias investigated in this study. Patients with cytopenias should

  8. Radioiodination of antibodies for tumor imaging

    International Nuclear Information System (INIS)

    Saha, G.B.

    1983-01-01

    In view of the great potential of radioiodinated antibody for the detection and treatment of cancer, the present article deals with the various techniques of radioiodination of antibody and their uses. Topics include methods of iodination of antibody, advantages and disadvantages of different methods, and effects of radioiodination on the antibody molecules with respect to their physiochemical and immunologic reactivity. In addition, the clinical usefulness of radioiodinated antibodies is discussed. (Auth.)

  9. Radioimmunological proof of thyroglobulin antibodies in humans by the use of a double antibody method

    International Nuclear Information System (INIS)

    Waller, V.

    1982-01-01

    Thyroid antibodies, especially thyroglobulin antibodies, allow themselves to be proven with the double antibody method, in competitive radio binding assays and with the solid phase technique. These methods offer advantages relative to sensitivity and quantifiability. In this work a sensitive radioimmunoassay as a double antibody method was worked out whereby a 125 I-thyroglobulin/thyroglobulin antibody immune complex was precipitated out using anti-human immunoglobulin. The measured results from the radioimmunoassay show a good correlation with the results of the immune histological findings. A high to very high Tg antibody level occurs with autoimmune thyroiditis (80%), primary hypothyroidism (74%) and hyperthyroidism (70%). The control values with healthy people came to less than 5% specific binding. In correlation with the results of other authors this method is advantageous relative to test start and evaluation procedures. (orig.) [de

  10. Synthetic peptides for antibody production

    NARCIS (Netherlands)

    N.D. Zegers (Netty)

    1995-01-01

    textabstractSynthetic peptides are useful tools for the generation of antibodies. The use of antibodies as specific reagents in inununochemical assays is widely applied. In this chapter, the application of synthetic peptides for the generation of antibodies is described. The different steps

  11. Monoclonal antibodies to Pneumocystis carinii

    DEFF Research Database (Denmark)

    Kovacs, J A; Halpern, J L; Lundgren, B

    1989-01-01

    To increase understanding of the antigenic structure of Pneumocystis carinii, we developed monoclonal antibodies to rat and human P. carinii. The specificity of the antibodies was demonstrated by immunofluorescence and immunoblot studies. Only one of five monoclonal antibodies to rat P. carinii r...

  12. Evaluation of the skin sensitization potential of chemicals using expression of co-stimulatory molecules, CD54 and CD86, on the naive THP-1 cell line.

    Science.gov (United States)

    Yoshida, Y; Sakaguchi, H; Ito, Y; Okuda, M; Suzuki, H

    2003-04-01

    It has been known that dendritic cells (DCs) including Langerhans cells (LCs) play a critical role in the skin sensitization process. Many attempts have been made to develop in vitro sensitization tests that employ DCs derived from peripheral blood mononuclear cells (PBMC-DC) or CD34+ hematopoietic progenitor cells (CD34+ HPC) purified from cord blood or bone marrow. However, the use of the DCs in in vitro methods has been difficult due to the nature of these cells such as low levels in the source and/or donor-to-donor variability. In our studies, we employed the human monocytic leukemia cell line, THP-1, in order to avoid some of these difficulties. At the start, we examined whether treatment of the cells with various cytokines could produce DCs from THP-1. Treatment of THP-1 cells with cytokines such as GM-CSF, IL-4, TNF-alpha, and/or PMA did induce some phenotypic changes in THP-1 cells that were characteristic of DCs. Subsequently, responses to a known sensitizer, dinitrochlorobenzene (DNCB), and a non-sensitizer, dimethyl sulfoxide (DMSO) or sodium lauryl sulfate (SLS), on the expression of co-stimulatory molecules, CD54 and CD86, were examined between the naive cells and the cytokine-treated cells. Interestingly, the naive THP-1 cells responded only to DNCB and the response to the sensitizer was more distinct than cytokine-treated THP-1 cells. Similar phenomena were also observed in the human myeloid leukemia cell line, KG-1. Furthermore, with treatment of DNCB, naive THP-1 cells showed augmented expression of HLA, CD80 and secretion of IL-1 beta. The response of THP-1 cells to a sensitizer was similar to that of LCs/DCs. Upon demonstrating the differentiation of monocyte cells in our system, we then evaluated a series of chemicals, including known sensitizers and non-sensitizers, for their potential to augment CD54 and CD86 expression on naive THP-1 cells. Indeed, known sensitizers such as PPD and 2-MBT significantly augmented CD54 and CD86 expression in a

  13. Cancer imaging with radiolabeled antibodies

    International Nuclear Information System (INIS)

    Goldenberg, D.M.

    1990-01-01

    This book presents a perspective of the use of antibodies to target diagnostic isotopes to tumors. Antibodies with reasonable specificity can be developed against almost any substance. If selective targeting to cancer cells can be achieved, the prospects for a selective therapy are equally intriguing. But the development of cancer detection, or imaging, with radiolabeled antibodies has depended upon advances in a number of different areas, including cancer immunology and immunochemistry for identifying suitable antigen targets and antibodies to these targets, tumor biology for model systems, radiochemistry for he attachment of radionuclides to antibodies, molecular biology for reengineering the antibodies for safer and more effective use in humans, and nuclear medicine for providing the best imaging protocols and instrumentation to detect minute amounts of elevated radioactivity against a background of considerable noise. Accordingly, this book has been organized to address the advances that are being made in many of these areas

  14. Application of the Naive Bayesian Classifier to optimize treatment decisions

    International Nuclear Information System (INIS)

    Kazmierska, Joanna; Malicki, Julian

    2008-01-01

    Background and purpose: To study the accuracy, specificity and sensitivity of the Naive Bayesian Classifier (NBC) in the assessment of individual risk of cancer relapse or progression after radiotherapy (RT). Materials and methods: Data of 142 brain tumour patients irradiated from 2000 to 2005 were analyzed. Ninety-six attributes related to disease, patient and treatment were chosen. Attributes in binary form consisted of the training set for NBC learning. NBC calculated an individual conditional probability of being assigned to: relapse or progression (1), or no relapse or progression (0) group. Accuracy, attribute selection and quality of classifier were determined by comparison with actual treatment results, leave-one-out and cross validation methods, respectively. Clinical setting test utilized data of 35 patients. Treatment results at classification were unknown and were compared with classification results after 3 months. Results: High classification accuracy (84%), specificity (0.87) and sensitivity (0.80) were achieved, both for classifier training and in progressive clinical evaluation. Conclusions: NBC is a useful tool to support the assessment of individual risk of relapse or progression in patients diagnosed with brain tumour undergoing RT postoperatively

  15. Stratification of Antibody-Positive Subjects by Antibody Level Reveals an Impact of Immunogenicity on Pharmacokinetics

    OpenAIRE

    Zhou, Lei; Hoofring, Sarah A.; Wu, Yu; Vu, Thuy; Ma, Peiming; Swanson, Steven J.; Chirmule, Narendra; Starcevic, Marta

    2012-01-01

    The availability of highly sensitive immunoassays enables the detection of antidrug antibody (ADA) responses of various concentrations and affinities. The analysis of the impact of antibody status on drug pharmacokinetics (PK) is confounded by the presence of low-affinity or low-concentration antibody responses within the dataset. In a phase 2 clinical trial, a large proportion of subjects (45%) developed ADA following weekly dosing with AMG 317, a fully human monoclonal antibody therapeutic....

  16. Impact of Uniform Methods on Interlaboratory Antibody Titration Variability: Antibody Titration and Uniform Methods.

    Science.gov (United States)

    Bachegowda, Lohith S; Cheng, Yan H; Long, Thomas; Shaz, Beth H

    2017-01-01

    -Substantial variability between different antibody titration methods prompted development and introduction of uniform methods in 2008. -To determine whether uniform methods consistently decrease interlaboratory variation in proficiency testing. -Proficiency testing data for antibody titration between 2009 and 2013 were obtained from the College of American Pathologists. Each laboratory was supplied plasma and red cells to determine anti-A and anti-D antibody titers by their standard method: gel or tube by uniform or other methods at different testing phases (immediate spin and/or room temperature [anti-A], and/or anti-human globulin [AHG: anti-A and anti-D]) with different additives. Interlaboratory variations were compared by analyzing the distribution of titer results by method and phase. -A median of 574 and 1100 responses were reported for anti-A and anti-D antibody titers, respectively, during a 5-year period. The 3 most frequent (median) methods performed for anti-A antibody were uniform tube room temperature (147.5; range, 119-159), uniform tube AHG (143.5; range, 134-150), and other tube AHG (97; range, 82-116); for anti-D antibody, the methods were other tube (451; range, 431-465), uniform tube (404; range, 382-462), and uniform gel (137; range, 121-153). Of the larger reported methods, uniform gel AHG phase for anti-A and anti-D antibodies had the most participants with the same result (mode). For anti-A antibody, 0 of 8 (uniform versus other tube room temperature) and 1 of 8 (uniform versus other tube AHG), and for anti-D antibody, 0 of 8 (uniform versus other tube) and 0 of 8 (uniform versus other gel) proficiency tests showed significant titer variability reduction. -Uniform methods harmonize laboratory techniques but rarely reduce interlaboratory titer variance in comparison with other methods.

  17. Synthetic peptides for antibody production

    NARCIS (Netherlands)

    Zegers, N.D.

    1995-01-01

    Synthetic peptides are useful tools for the generation of antibodies. The use of antibodies as specific reagents in inununochemical assays is widely applied. In this chapter, the application of synthetic peptides for the generation of antibodies is described. The different steps that lead to the

  18. Structural brain correlates of sensorimotor gating in antipsychotic-naive men with first-episode schizophrenia

    DEFF Research Database (Denmark)

    Hammer, Trine B; Oranje, Bob; Skimminge, Arnold

    2013-01-01

    in the left rostral dorsal premotor cortex, the right presupplementary motor area and the anterior medial superior frontal gyrus bilaterally. Follow-up analyses suggested that the rostral dorsal premotor cortex and presupplementary motor area correlations were driven predominantly by the controls. Limitations......Background: Prepulse inhibition (PPI) of the startle reflex is modulated by a complex neural network. Prepulse inhibition impairments are found at all stages of schizophrenia. Previous magnetic resonance imaging (MRI) studies suggest that brain correlates of PPI differ between patients...... with schizophrenia and healthy controls; however, these studies included only patients with chronic illness and medicated patients. Our aim was to examine the structural brain correlates of PPI in antipsychotic-naive patients with first-episode schizophrenia. Methods: We performed acoustic PPI assessment...

  19. A novel antibody engineering strategy for making monovalent bispecific heterodimeric IgG antibodies by electrostatic steering mechanism.

    Science.gov (United States)

    Liu, Zhi; Leng, Esther C; Gunasekaran, Kannan; Pentony, Martin; Shen, Min; Howard, Monique; Stoops, Janelle; Manchulenko, Kathy; Razinkov, Vladimir; Liu, Hua; Fanslow, William; Hu, Zhonghua; Sun, Nancy; Hasegawa, Haruki; Clark, Rutilio; Foltz, Ian N; Yan, Wei

    2015-03-20

    Producing pure and well behaved bispecific antibodies (bsAbs) on a large scale for preclinical and clinical testing is a challenging task. Here, we describe a new strategy for making monovalent bispecific heterodimeric IgG antibodies in mammalian cells. We applied an electrostatic steering mechanism to engineer antibody light chain-heavy chain (LC-HC) interface residues in such a way that each LC strongly favors its cognate HC when two different HCs and two different LCs are co-expressed in the same cell to assemble a functional bispecific antibody. We produced heterodimeric IgGs from transiently and stably transfected mammalian cells. The engineered heterodimeric IgG molecules maintain the overall IgG structure with correct LC-HC pairings, bind to two different antigens with comparable affinity when compared with their parental antibodies, and retain the functionality of parental antibodies in biological assays. In addition, the bispecific heterodimeric IgG derived from anti-HER2 and anti-EGF receptor (EGFR) antibody was shown to induce a higher level of receptor internalization than the combination of two parental antibodies. Mouse xenograft BxPC-3, Panc-1, and Calu-3 human tumor models showed that the heterodimeric IgGs strongly inhibited tumor growth. The described approach can be used to generate tools from two pre-existent antibodies and explore the potential of bispecific antibodies. The asymmetrically engineered Fc variants for antibody-dependent cellular cytotoxicity enhancement could be embedded in monovalent bispecific heterodimeric IgG to make best-in-class therapeutic antibodies. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. Application of cyclodextrins in antibody microparticles: potentials for antibody protection in spray drying.

    Science.gov (United States)

    Ramezani, Vahid; Vatanara, Alireza; Seyedabadi, Mohammad; Nabi Meibodi, Mohsen; Fanaei, Hamed

    2017-07-01

    Dry powder formulations are extensively used to improve the stability of antibodies. Spray drying is one of important methods for protein drying. This study investigated the effects of trehalose, hydroxypropyl beta cyclodextrin (HPBCD) and beta cyclodextrin (BCD) on the stability and particle properties of spray-dried IgG. D-optimal design was employed for both experimental design and analysis and optimization of the variables. The size and aerodynamic behavior of particles were determined using laser light scattering and glass twin impinger, respectively. In addition, stability, ratio of beta sheets and morphology of antibody were analyzed using size exclusion chromatography, IR spectroscopy and electron microscopy, respectively. Particle properties and antibody stability were significantly improved in the presence of HPBCD. In addition, particle aerodynamic behavior, in terms of fine-particle fraction (FPF), enhanced up to 52.23%. Furthermore, antibody was better preserved not only during spray drying, but also during long-term storage. In contrast, application of BCD resulted in the formation of larger particles. Although trehalose caused inappropriate aerodynamic property, it efficiently decreased antibody aggregation. HPBCD is an efficient excipient for the development of inhalable protein formulations. In this regard, optimal particle property and antibody stability was obtained with proper combination of cyclodextrins and simple sugars, such as trehalose.

  1. Tumor detection using radiolabeled monoclonal antibodies

    International Nuclear Information System (INIS)

    Moldofsky, P.J.; Powe, J.; Hammond, N.D.

    1987-01-01

    Radioisotope conjugated to monoclonal antibody products has been used for imaging tumors targeted by the antibody. As imaging progresses, new sets of procedural and technical questions arise. In this chapter, we discuss several current problems in imaging tumor with radiolabeled monoclonal antibody. These include (1) methods for selection of specific antibody and, once the particular antibody is selected, which fragment form is to be used; (2) imaging procedures: what are the optimum imaging parameters, such as optimum time for imaging after administration of tracer and considerations regarding background subtraction; and (3) noninvasive quantitative techniques: quantitation of localization of antibody indirectly from quantitative information in the images.100 references

  2. Frequently relapsing anti-glomerular basement membrane antibody disease with changing clinical phenotype and antibody characteristics over time

    OpenAIRE

    Gu, Bobby; Magil, Alex B.; Barbour, Sean J.

    2016-01-01

    Anti-glomerular basement membrane (GBM) antibody disease is a typically monophasic autoimmune disease with severe pulmonary and renal involvement. We report an atypical case of frequently relapsing anti-GBM antibody disease with both anti-GBM antibody?positive flares with pulmonary and renal involvement, and anti-GBM antibody?negative flares that were pulmonary limited with no histologic renal disease. This is the first report of alternating disease phenotype and anti-GBM antibody status over...

  3. Detection of anti-lactoferrin antibodies and anti-myeloperoxidase antibodies in autoimmune hepatitis: a retrospective study.

    Science.gov (United States)

    Tan, Liming; Zhang, Yuhong; Peng, Weihua; Chen, Juanjuan; Li, Hua; Ming, Feng

    2014-01-01

    Anti-lactoferrin antibodies (ALA) and anti-myeloperoxidase antibodies (AMPA) are specific serological markers for autoimmune hepatitis (AIH). The project aimed to detect ALA and AMPA and explore their clinical significances in AIH patients. 59 AIH patients, 217 non AIH patients, and 50 healthy controls were enrolled in this study. ALA and AMPA were detected by ELISA. Antineutropil cytoplasmic antibodies (ANCA) and anti-smooth muscle antibodies (ASMA) were examined by indirect immunofluorescence. Antimitochondrial antibody M2 subtype (AMA-M2), anti-liver kidney microsomal antibody Type 1 (LKM1), anti-liver cytosol antibody Type 1 (LC1), and anti-soluble liver antigen/liver-pancreas antibodies (SLA/LP) were tested by immunoblot. The positivity for ALA was 18.6% in AIH group, only one patient in non-AIH group was positive for ALA; the positivity for AMPA was 59.3% in AIH group, with significant differences (P < 0.01) compared with other groups. The specificities for ALA and AMPA were 99.63% and 97.75%; the sensitivities were 18.64% and 59.32%; and the accuracy rates were 84.97% and 90.80%, respectively. A certain correlation was observed between ALA and SLA/LP, AMPA and ANCA, ASMA in AIH group. ALA and AMPA were associated with AIH, and had high clinical diagnostic value. Co-detection with other relative autoantibodies could play an important role in differential diagnosis of AIH.

  4. Which thoughts can kill a boxer? naive theories about cognitive and emotional antecedents of suicide.

    Science.gov (United States)

    Spörrle, Matthias; Försterling, Friedrich

    2007-12-01

    We investigated naive theories regarding the association among beliefs, emotions and behaviours to test Rational Emotive Behaviour Therapy's (REBT) assumption that rational cognitions and adaptive emotions lead to functional behaviours whereas irrational cognitions and maladaptive emotions trigger dysfunctional reactions. We applied an experimental between-subjects design. Participants read newspaper articles about the defeat of a boxer. In one condition, the authentic article informed participants that he committed suicide and in the other, a fictitious article about the same defeat described the athlete as successfully continuing his career. Different question formats were employed to assess participants' assumptions about the stimulus person's defeat-related cognitions and emotions: rating scales, sentence completion and free responses. Participants assumed significantly more irrational beliefs (e.g. I absolutely have to win) on the side of the boxer in the suicide scenario than in the non-suicide version. This finding was obtained by directive and non-directive assessment methods. Additionally, participants expected the suicidal stimulus person to be experiencing maladaptive emotions (e.g. depression, guilt) whereas a successful resumption of his career lead to expectations of adaptive affects (e.g. sadness, concern). Ratings of the functionality revealed that sadness, fear, annoyance and concern were expected to be more functional than depression, anxiety, rage and guilt. The results show that naive psychological theories about the antecedents of dysfunctional behaviour are in accordance with theoretical assumptions of REBT: Irrational beliefs are viewed to be connected with maladaptive emotions and to result in dysfunctional behaviour, and adaptive emotions are thought to be of higher functional value than their maladaptive counterparts. The use of different question formats and a between-subject design excluded that results are due to methodological

  5. Structural Characterization of Peptide Antibodies

    DEFF Research Database (Denmark)

    Chailyan, Anna; Marcatili, Paolo

    2015-01-01

    The role of proteins as very effective immunogens for the generation of antibodies is indisputable. Nevertheless, cases in which protein usage for antibody production is not feasible or convenient compelled the creation of a powerful alternative consisting of synthetic peptides. Synthetic peptides...... can be modified to obtain desired properties or conformation, tagged for purification, isotopically labeled for protein quantitation or conjugated to immunogens for antibody production. The antibodies that bind to these peptides represent an invaluable tool for biological research and discovery....... To better understand the underlying mechanisms of antibody-antigen interaction here we present a pipeline developed by us to structurally classify immunoglobulin antigen binding sites and to infer key sequence residues and other variables that have a prominent role in each structural class....

  6. Drug resistance mutations in HIV type 1 isolates from naive patients eligible for first line antiretroviral therapy in JJ Hospital, Mumbai, India.

    Science.gov (United States)

    Deshpande, Alake; Karki, Surendra; Recordon-Pinson, Patricia; Fleury, Herve J

    2011-12-01

    More than 50 HIV-1-infected patients, naive of antiretroviral therapy (ART) but eligible for first line ART in JJ Hospital, Mumbai, India were investigated for surveillance drug resistance mutations (SDRMs); all but one virus belonged to subtype C; we could observe SDRMs to nonnucleoside reverse transcriptase inhibitors and protease inhibitors in 9.6% of the patients.

  7. [11C]Choline PET/CT predicts survival in hormone-naive prostate cancer patients with biochemical failure after radical prostatectomy

    International Nuclear Information System (INIS)

    Giovacchini, Giampiero; Incerti, Elena; Mapelli, Paola; Gianolli, Luigi; Picchio, Maria; Kirienko, Margarita; Briganti, Alberto; Gandaglia, Giorgio; Montorsi, Francesco

    2015-01-01

    Over the last decade, PET/CT with radiolabelled choline has been shown to be useful for restaging patients with prostate cancer (PCa) who develop biochemical failure. The limitations of most clinical studies have been poor validation of [ 11 C]choline PET/CT-positive findings and lack of survival analysis. The aim of this study was to assess whether [ 11 C]choline PET/CT can predict survival in hormone-naive PCa patients with biochemical failure. This retrospective study included 302 hormone-naive PCa patients treated with radical prostatectomy who underwent [ 11 C]choline PET/CT from 1 December 2004 to 31 July 2007 because of biochemical failure (prostate-specific antigen, PSA, >0.2 ng/mL). Median PSA was 1.02 ng/mL. PCa-specific survival was estimated using Kaplan-Meier curves. Cox regression analysis was used to evaluate the association between clinicopathological variables and PCa-specific survival. The coefficients of the covariates included in the Cox regression analysis were used to develop a novel nomogram. Median follow-up was 7.2 years (1.4 - 18.9 years). [ 11 C]Choline PET/CT was positive in 101 of 302 patients (33 %). Median PCa-specific survival after prostatectomy was 14.9 years (95 % CI 9.7 - 20.1 years) in patients with positive [ 11 C]choline PET/CT. Median survival was not achieved in patients with negative [ 11 C]choline PET/CT. The 15-year PCa-specific survival probability was 42.4 % (95 % CI 31.7 - 53.1 %) in patients with positive [ 11 C]choline PET/CT and 95.5 % (95 % CI 93.5 - 97.5 %) in patients with negative [ 11 C]choline PET/CT. In multivariate analysis, [ 11 C]choline PET/CT (hazard ratio 6.36, 95 % CI 2.14 - 18.94, P < 0.001) and Gleason score >7 (hazard ratio 3.11, 95 % CI 1.11 - 8.66, P = 0.030) predicted PCa-specific survival. An internally validated nomogram predicted 15-year PCa-specific survival probability with an accuracy of 80 %. Positive [ 11 C]choline PET/CT after biochemical failure predicts PCa-specific survival in hormone-naive

  8. Antibodies against linear epitopes on Goodpasture autoantigen in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis.

    Science.gov (United States)

    Jia, Xiao-Yu; Yu, Jun-Tao; Hu, Shui-Yi; Li, Jian-Nan; Wang, Miao; Wang, Chen; Chen, Min; Cui, Zhao; Zhao, Ming-Hui

    2017-09-01

    In a substantial number of patients with crescentic glomerulonephritis, both anti-glomerular basement membrane (GBM) antibodies and anti-neutrophil cytoplasmic antibodies (ANCA) are detected simultaneously. ANCA is presumed to be the initial event but the mechanism is unknown. In the present study, we investigated the antibodies against linear epitopes on Goodpasture autoantigen in sera from patients with ANCA-associated vasculitis, aiming to reveal the mechanisms of the coexistence of the two kinds of autoantibodies. Thirty-one patients with ANCA-associated vasculitis were enrolled in this study. Twenty-four overlapping linear peptides were synthesized across the whole sequence of Goodpasture autoantigen. Serum antibodies against linear peptides were detected by ELISA and their associations with clinical features were further analyzed. Twenty-five out of the thirty-one (80.6%) sera from patients with ANCA-associated vasculitis possessed antibodies against linear peptides on Goodpasture autoantigen. These antibodies could be detected in 50% of patients with normal renal function (Scr ≤ 133 μmol/L), 70% of patients with moderate renal dysfunction (133 μmol/L  600 μmol/L) (P = 0.032). The highest recognition frequencies were found for peptides P4 (51.6%), P14 (54.8%), and P24 (54.8%), which contained the sequences that constitute the conformational epitopes of E A (P4) and E B (P14) recognized by anti-GBM antibodies. The level of anti-P4 antibodies was positively correlated with the percentage of crescents in glomeruli (r = 0.764, P = 0.027). Patients with anti-P24 antibodies had a significantly higher prevalence of renal dysfunction on diagnosis (88.2 vs. 42.9%, P = 0.018). Antibodies against linear epitopes on Goodpasture autoantigen could be detected in sera of patients with ANCA-associated vasculitis, which might mediate the production of antibodies towards the conformational epitopes on Goodpasture autoantigen, namely, the anti-GBM antibodies.

  9. Optimization of Candidate Selection Using Naive Bayes: Case Study in Company X

    Science.gov (United States)

    Kadar, JA; Agustono, D.; Napitupulu, D.

    2018-01-01

    This research was conducted as a decision-making system, and an alternative solution to complete the candidate assessment for a particular position. The human resources (HR) section on company X is responsible and initiative in selecting candidates in accordance with the assessment of their superiors. Selection by using the method of filling out the manager’s assessment questionnaire on the candidate’s subordinate. Three (3) managers have been determined to assess the 11 candidates for subordinates. By using questionnaire of quality classification of human resources and formula naive bayes it will get result which finally grouped using criteria scale as final grouping. The HR department has also determined that what is received is that which meets criteria 5. The result is three (3) candidates who can be proposed as candidates for certain positions in company X, and have met all required calculations. Furthermore the candidate will be given to management as an alternative input data in the selection of candidates.

  10. RosettaAntibodyDesign (RAbD): A general framework for computational antibody design.

    Science.gov (United States)

    Adolf-Bryfogle, Jared; Kalyuzhniy, Oleks; Kubitz, Michael; Weitzner, Brian D; Hu, Xiaozhen; Adachi, Yumiko; Schief, William R; Dunbrack, Roland L

    2018-04-01

    A structural-bioinformatics-based computational methodology and framework have been developed for the design of antibodies to targets of interest. RosettaAntibodyDesign (RAbD) samples the diverse sequence, structure, and binding space of an antibody to an antigen in highly customizable protocols for the design of antibodies in a broad range of applications. The program samples antibody sequences and structures by grafting structures from a widely accepted set of the canonical clusters of CDRs (North et al., J. Mol. Biol., 406:228-256, 2011). It then performs sequence design according to amino acid sequence profiles of each cluster, and samples CDR backbones using a flexible-backbone design protocol incorporating cluster-based CDR constraints. Starting from an existing experimental or computationally modeled antigen-antibody structure, RAbD can be used to redesign a single CDR or multiple CDRs with loops of different length, conformation, and sequence. We rigorously benchmarked RAbD on a set of 60 diverse antibody-antigen complexes, using two design strategies-optimizing total Rosetta energy and optimizing interface energy alone. We utilized two novel metrics for measuring success in computational protein design. The design risk ratio (DRR) is equal to the frequency of recovery of native CDR lengths and clusters divided by the frequency of sampling of those features during the Monte Carlo design procedure. Ratios greater than 1.0 indicate that the design process is picking out the native more frequently than expected from their sampled rate. We achieved DRRs for the non-H3 CDRs of between 2.4 and 4.0. The antigen risk ratio (ARR) is the ratio of frequencies of the native amino acid types, CDR lengths, and clusters in the output decoys for simulations performed in the presence and absence of the antigen. For CDRs, we achieved cluster ARRs as high as 2.5 for L1 and 1.5 for H2. For sequence design simulations without CDR grafting, the overall recovery for the native

  11. Anti-smooth muscle antibody

    Science.gov (United States)

    ... gov/ency/article/003531.htm Anti-smooth muscle antibody To use the sharing features on this page, please enable JavaScript. Anti-smooth muscle antibody is a blood test that detects the presence ...

  12. Antibodies against chromosomal beta-lactamase

    DEFF Research Database (Denmark)

    Giwercman, B; Rasmussen, J W; Ciofu, Oana

    1994-01-01

    A murine monoclonal anti-chromosomal beta-lactamase antibody was developed and an immunoblotting technique was used to study the presence of serum and sputum antibodies against Pseudomonas aeruginosa chromosomal group 1 beta-lactamase in patients with cystic fibrosis (CF). The serum antibody...... 1 cephalosporinase. We found a wide range of chromosomal beta-lactamase activity in the sputum samples, with no correlation with basal or induced activity of beta-lactamase expression. The presence of anti-beta-lactamase antibodies in endobronchial sputum could be an important factor in the defense...

  13. Radiolabelled antibodies in imaging

    International Nuclear Information System (INIS)

    Khaw, B.A.; Haber, E.

    1982-01-01

    Recent technological advances make it possible to produce pure (monoclonal) antibodies in unlimited quantities without the need for continuous immunization of animals and to label these antibodies with a variety of radionuclides which can be traced by single-photon computed tomography. An outline review of the state of the art is presented, with particular reference to the imaging of myocardial infarcts and to tumour imaging studies using labelled monoclonal antibodies (sup(99m)Tc and 125 I). Lengthy bibliography. (U.K.)

  14. Replication capacity in relation to immunologic and virologic outcomes in HIV-1-infected treatment-naive subjects.

    Science.gov (United States)

    Skowron, Gail; Spritzler, John G; Weidler, Jodi; Robbins, Gregory K; Johnson, Victoria A; Chan, Ellen S; Asmuth, David M; Gandhi, Rajesh T; Lie, Yolanda; Bates, Michael; Pollard, Richard B

    2009-03-01

    To evaluate the association between baseline (BL) replication capacity (RC) (RCBL) and immunologic/virologic parameters (at BL and after 48 weeks on therapy) in HIV-1-infected subjects initiating antiretroviral therapy. RCBL was determined using a modified Monogram PhenoSense HIV drug susceptibility assay on plasma HIV-1 from 321 treatment-naive subjects from AIDS Clinical Trials Group 384. Univariate and multivariable analyses were performed to determine the association of RCBL with BL and on-therapy virologic and immunologic outcomes. Higher RCBL was associated with lower baseline CD4 (CD4BL) (r = -0.23, P < 0.0001), higher baseline HIV-1 RNA (r = 0.25, P < 0.0001), higher CD4BL activation percent (r = 0.23, P < 0.0001), and lower CD4BL memory count (r = -0.21, P = 0.0002). In a multivariable model, week 48 CD4 increase (DeltaCD448) was associated with lower CD4BL memory count and higher CD4BL-naive percent (P = 0.004, P = 0.015, respectively). The interaction between CD4BL and RCBL was significant (P = 0.018), with a positive association between RCBL and DeltaCD448 in subjects with higher CD4BL and a negative association at lower absCD4BL. At baseline, higher RC was significantly associated with higher HIV-1 RNA, higher CD4 cell activation, lower CD4 cell count, and lower CD4 memory cell count. These factors may interact, directly or indirectly, to modify the extent to which CD4 recovery occurs in patients starting antiretroviral therapy at different CD4BL counts.

  15. Modification of Antibody Function by Mutagenesis.

    Science.gov (United States)

    Dasch, James R; Dasch, Amy L

    2017-09-01

    The ability to "fine-tune" recombinant antibodies by mutagenesis separates recombinant antibodies from hybridoma-derived antibodies because the latter are locked with respect to their properties. Recombinant antibodies can be modified to suit the application: Changes in isotype, format (e.g., scFv, Fab, bispecific antibodies), and specificity can be made once the heavy- and light-chain sequences are available. After immunoglobulin heavy and light chains for a particular antibody have been cloned, the binding site-namely, the complementarity determining regions (CDR)-can be manipulated by mutagenesis to obtain antibody variants with improved properties. The method described here is relatively simple, uses commercially available reagents, and is effective. Using the pComb3H vector, a commercial mutagenesis kit, PfuTurbo polymerase (Agilent), and two mutagenic primers, a library of phage with mutagenized heavy and light CDR3 can be obtained. © 2017 Cold Spring Harbor Laboratory Press.

  16. Depletion of naive CD4 T cells by CXCR4-using HIV-1 variants occurs mainly through increased T-cell death and activation

    NARCIS (Netherlands)

    Hazenberg, Mette D.; Otto, Sigrid A.; Hamann, Dörte; Roos, Marijke Th L.; Schuitemaker, Hanneke; de Boer, Rob J.; Miedema, Frank

    2003-01-01

    Objective: Using SCID-Hu mice models and in vitro culture systems, it has been shown that syncytium inducing/CXCR4 using (X4) HIV-1 variants affect thymic function through infection and killing of CXCR4 thymocytes. The effect of X4-emergence on naive, memory and effector T-cell subset kinetics in

  17. Stability of prepulse inhibition and habituation of the startle reflex in schizophrenia: a 6-year follow-up study of initially antipsychotic-naive, first-episode schizophrenia patients

    DEFF Research Database (Denmark)

    Hammer, Trine Bjørg; Oranje, Bob; Fagerlund, Birgitte

    2011-01-01

    and is regarded as an endophenotype for schizophrenia. However, reports on the stability of PPI over a longer period of time are lacking, both for patients with schizophrenia and for healthy subjects. The current study examined 25 initially drug-naive, first-episode schizophrenia patients and 23 healthy matched...... not change in patients or controls. The present results show that PPI in drug-naive, first-episode schizophrenia patients can improve significantly over time. As PPI increased in patients over the same period that it decreased in controls, it is likely that the increase was caused by disease-related factors......Deficits in information processing appear to be core features in the pathogenesis of schizophrenia. Prepulse inhibition (PPI) and habituation of the startle reflex are operational measures of early information processing. Impaired PPI in schizophrenia has been replicated in many studies...

  18. Dengue-Immune Humans Have Higher Levels of Complement-Independent Enhancing Antibody than Complement-Dependent Neutralizing Antibody.

    Science.gov (United States)

    Yamanaka, Atsushi; Konishi, Eiji

    2017-09-25

    Dengue is the most important arboviral disease worldwide. We previously reported that most inhabitants of dengue-endemic countries who are naturally immune to the disease have infection-enhancing antibodies whose in vitro activity does not decrease in the presence of complement (complement-independent enhancing antibodies, or CiEAb). Here, we compared levels of CiEAb and complement-dependent neutralizing antibodies (CdNAb) in dengue-immune humans. A typical antibody dose-response pattern obtained in our assay system to measure the balance between neutralizing and enhancing antibodies showed both neutralizing and enhancing activities depending on serum dilution factor. The addition of complement to the assay system increased the activity of neutralizing antibodies at lower dilutions, indicating the presence of CdNAb. In contrast, similar dose-response curves were obtained with and without complement at higher dilutions, indicating higher levels of CiEAb than CdNAb. For experimental support for the higher CiEAb levels, a cocktail of mouse monoclonal antibodies against dengue virus type 1 was prepared. The antibody dose-response curves obtained in this assay, with or without complement, were similar to those obtained with human serum samples when a high proportion of D1-V-3H12 (an antibody exhibiting only enhancing activity and thus a model for CiEAb) was used in the cocktail. This study revealed higher-level induction of CiEAb than CdNAb in humans naturally infected with dengue viruses.

  19. Antibodies to watch in 2014.

    Science.gov (United States)

    Reichert, Janice M

    2014-01-01

    Since 2010, mAbs has documented the biopharmaceutical industry's progress in transitioning antibody therapeutics to first Phase 3 clinical studies and regulatory review, and its success at gaining first marketing approvals for antibody-based products. This installment of the "Antibodies to watch" series outlines events anticipated to occur between December 2013 and the end of 2014, including first regulatory actions on marketing applications for vedolizumab, siltuximab, and ramucirumab, as well as the Fc fusion proteins Factor IX-Fc and Factor VIII-Fc; and the submission of first marketing applications for up to five therapeutics (secukinumab, ch14.18, onartuzumab, necitumumab, gevokizumab). Antibody therapeutics in Phase 3 studies are described, with an emphasis on those with study completion dates in 2014, including antibodies targeting interleukin-17a or the interleukin-17a receptor (secukinumab, ixekizumab, brodalumab), proprotein convertase subtilisin/kexin type 9 (alirocumab, evolocumab, bococizumab), and programmed death 1 receptor (lambrolizumab, nivolumab). Five antibodies with US Food and Drug Administration's Breakthrough Therapy designation (obinutuzumab, ofatumumab, lambrolizumab, bimagrumab, daratumumab) are also discussed.

  20. Avian Diagnostic and Therapeutic Antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, David Sherman [UND SMHS

    2012-12-31

    A number of infectious agents have the potential of causing significant clinical symptomology and even death, but dispite this, the number of incidence remain below the level that supports producing a vaccine. Therapeutic antibodies provide a viable treatment option for many of these diseases. We proposed that antibodies derived from West Nile Virus (WNV) immunized geese would be able to treat WNV infection in mammals and potential humans. We demonstrated that WNV specific goose antibodies are indeed successful in treating WNV infection both prophylactically and therapeutically in a golden hamster model. We demonstrated that the goose derived antibodies are non-reactogenic, i.e. do not cause an inflammatory response with multiple exposures in mammals. We also developed both a specific pathogen free facility to house the geese during the antibody production phase and a patent-pending purification process to purify the antibodies to greater than 99% purity. Therefore, the success of these study will allow a cost effective rapidly producible therapeutic toward clinical testing with the necessary infrastructure and processes developed and in place.