Sample records for antibody test development

  1. Development and evaluation of an enzyme-labeled antibody test for the rapid detection of hog cholera antibodies

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    Saunders, G.C.


    A rapid enzyme-labeled antibody (ELA) microtechnique for the screening of swine for hog cholera antibodies was developed and evaluated with a blind study, using a 640-sample hog cholera serum bank. The total time to run a group of 22 samples was approximately 1 hour. The ELA test results correlated >99% with hog cholera serum-neutralization test results on the same serums. Test results also indicated that the ELA test shares with the hog cholera serum-neutralization test the problem of cross reactions between the antibodies of hog cholera and bovine viral diarrhea.

  2. Development and Testing of Recombinant Single Domain Antibodies (United States)


    single domain antibodies from a naïve shark library. Molecular Immunology. 44:1786-1794. Sherwood, L.J., Osborn, L., Carrion , R., Patterson, J., Hayhurst...for viral diagnostics in hot climates 9. Sherwood, L.J., Osborn, L, Carrion , R., Patterson, J.P and Hayhurst, A. April 22, 2007 Rapid assembly of...and Austin Life Sciences Association, New Bruanfels, TX. 11. Sherwood, L.J., Osborn, L., Carrion , R., Patterson, J.P. and Hayhurst, A. May 14, 2007

  3. Development of a blocking latex agglutination test for the detection of antibodies to chicken anemia virus. (United States)

    Trinh, Dai Quang; Ogawa, Haruko; Bui, Vuong Nghia; Nguyen, Tham Thi Hong; Gronsang, Dulyatad; Baatartsogt, Tugsbaatar; Kizito, Mugimba Kahoza; AboElkhair, Mohammed; Yamaguchi, Shigeo; Nguyen, Viet Khong; Imai, Kunitoshi


    A blocking latex agglutination test (b-LAT) developed in this study was evaluated for the detection of antibodies against chicken anemia virus (CAV) in chickens. Polystyrene latex beads were coupled with a neutralizing monoclonal antibody (mAb) to CAV (mAb-beads). When mAb-beads were mixed with antigens prepared from the lysate of MDCC-MSB1 cells infected with CAV, agglutination occurred. A short pre-incubation of CAV antigens with CAV-specific antiserum inhibited the agglutination of mAb-beads. The test results were obtained within 5min. The specificity of b-LAT was evaluated using sera from specific pathogen-free chickens and sera containing antibodies to avian influenza virus, Newcastle disease virus, infectious bursal disease virus, and Marek's disease virus; nonspecific agglutination and cross-reactivity with antibodies to unrelated viruses were not observed. The examination of 94 serum samples collected from commercial breeder chickens of various ages (17-63 weeks) revealed good agreement (93.6%, Kappa value=0.82) between b-LAT and a virus neutralization test, known to be most sensitive and specific in the detection of antibodies to CAV. These results indicate that b-LAT, a simple and rapid test, is a useful and reliable tool in CAV serology.

  4. Development of a Specific Latex Agglutination Test to Detect Antibodies of Enterovirus 71. (United States)

    Qin, Bo; Zhang, Jianhua; Xie, Wenhao; Liu, Xuehong; He, Tingting; Chen, Jinkun; Dong, Xuejun


    A latex agglutination test (LAT) was developed for the rapid detection of antibodies against the VP1 or VP1 proteins of Enterovirus 71 (EV71). The proteins of interest including prokaryotically expressed VP1 and two strains of anti-VP1 monoclonal antibody (McAb) against EV71 were covalently linked to carboxylated latex using ethyl-dimethyl-amino-propyl carbodiimide (EDC) to prepare sensitized latex beads. LAT was evaluated by an enzyme-linked immunosorbent assay (ELISA) as a reference test. The VP1-LAT showed a sensitivity of 87.0%, specificity of 88.9%, and an agreement ratio of 90.0% in detecting VP1 in 100 serum samples from experimentally infected mice, whereas these values were 86.8, 96.7, and 93.3%, respectively, for 608 clinical human serum samples. The VP1-LAT has advantages over other assays in terms of low cost, rapidity, chemical stability, high sensitivity, repeatability, and specificity. The LAT established in the present study is a rapid and simple test suitable for field monitoring of antibodies against VP1-EV71.

  5. Antibody Blood Tests (United States)

    ... What do I do if I have a negative blood test (or panel) but I’m still having symptoms? While it is rare, it is possible for patients to have a negative antibody test results and still have celiac disease. ...

  6. Anti-insulin antibody test (United States)

    Insulin antibodies - serum; Insulin Ab test; Insulin resistance - insulin antibodies; Diabetes - insulin antibodies ... You appear to have an allergic response to insulin Insulin no longer seems to control your diabetes

  7. Antiparietal cell antibody test (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; ...

  8. Sensitive neutralization test for rubella antibody. (United States)

    Sato, H; Albrecht, P; Krugman, S; Ennis, F A


    A modified rubella virus plaque neutralization test for measuring rubella antibody was developed based on the potentiation of the virus-antibody complex by heterologous anti-immunoglobulin. The test is highly sensitive, yielding titers on the average 50 to 100 times higher than the haemagglutination inhibition test or the conventional plaque neutralization test. The sensitivity of this enhanced neutralization test is somewhat limited by the existence of a prozone phenomenon which precludes testing of low-titered sera below a dilution of 1:16. No prozone effect was observed with cerebrospinal fluids. The specificity of the enhanced neutralization test was determined by seroconversion of individuals receiving rubella vaccine. Although the rubella hemagglutination inhibition test remains the test of choice in routine diagnostic and surveillance work, the enhanced rubella neutralization test is particularly useful in monitoring low-level antibody in the cerebrospinal fluid in patients with neurological disorders and in certain instances of vaccine failure. PMID:107192

  9. ANA (Antinuclear Antibody Test) (United States)

    Advertisement Proceeds from website advertising help sustain Lab Tests Online. AACC is a not-for-profit organization and does not endorse non-AACC products and services. Advertising & Sponsorship: Policy | Opportunities ...

  10. HIV Antibody Test (United States)

    ... 2 has a higher prevalence in parts of Africa.) The level of p24 antigen and the amount ... getting pregnant may opt to get tested (see Pregnancy: HIV .) The ... Teens , Young Adults , Adults , and Adults 50 and Up . ...

  11. Development of a Time and Cost Benefit Antibody Binding Test-Based Method for Determination of Rabies Vaccine Potency. (United States)

    Asgary, Vahid; Mojtabavi, Nazanin; Janani, Alireza; Mousavi, Tahereh; Hadjati, Jamshid; Khosravy, Mohammad Sadeq; Ahangari Cohan, Reza


    This study is an improvement on the antibody binding test, known as ABT method, to develop a simple and fast method in comparison with NIH for determination of rabies vaccine potency. In the current study, several commercial human and veterinary vaccines were tested using both modified ABT and NIH methods. The ED50 was calculated using the probit method and the relative potency of each vaccine was measured based on the reference vaccine. The test was repeated four times to calculate the reproducibility of the method. Statistical analysis indicated that there was no significant difference between the result obtained from NIH and modified ABT method for either human or veterinary vaccines (p > 0.05). In addition, the linearity of the method (R(2)) was calculated as 0.94 by serial dilution of a test vaccine. Coefficient variances were determined as less than and more than 10% for the human and veterinary rabies vaccines, respectively. In conclusion, the findings suggest that the modified method could be considered as an alternative approach for rabies vaccine potency determination in in-process quality control tests at industrial scale. It is a time and cost benefit method and accuracy may further be increased by employing monoclonal antibodies against trimeric form of G glycoprotein. However, the use of serum samples may be useful compared with an artificial mix of antibodies because other components from the serum samples could have a positive impact on cell sensitivity and mimic more the complexity of the immune response. Although the modified test has solved a fundamental problem, it is still not sensitive enough for veterinary vaccine assessment and needs further modifications to obtain the acceptability criteria.

  12. Development and characterization of a human antibody reference panel against erythropoietin suitable for the standardization of ESA immunogenicity testing. (United States)

    Mytych, Daniel T; Barger, Troy E; King, Chadwick; Grauer, Stephanie; Haldankar, Raj; Hsu, Eric; Wu, Michelle Min; Shiwalkar, Mukta; Sanchez, Sergio; Kuck, Andrew; Civoli, Francesca; Sun, Jilin; Swanson, Steven J


    Recombinant human erythropoietin (EPO) has been used therapeutically for more than two decades in the treatment of anemia. Although EPO is generally well tolerated, in rare cases, patients have developed anti-EPO antibodies that can negatively impact safety and efficacy. Therefore, the detection of antibodies against EPO is a regulatory requirement during clinical development and post-approval. Although it is a rare phenomenon, antibody-mediated pure red cell aplasia (PRCA) is a serious complication than can result from antibodies that develop and neutralize EPO as well as endogenous erythropoietin. Currently, there are no universally accepted analytical methods to detect the full repertoire of binding and neutralizing anti-EPO antibodies. A number of different methods that differ in terms of antibodies detected and assay sensitivities are used by different manufacturers. There is also a lack of antibody reference reagents, and therefore no consistent basis for detecting and measuring anti-EPO antibodies. Reference reagents, with established ranges, are essential to monitor the safety and efficacy of all erythropoiesis-stimulating agents (ESAs) structurally related to human erythropoietin. This is the first report of the development and characterization of a panel of fully human antibodies against EPO suitable as reference reagents. The characteristics of antibodies within the panel were selected based on the prevalence of non-neutralizing IgG and IgM antibodies in non-PRCA patients and neutralizing IgG antibodies, including IgG1 and IgG4, in antibody-mediated PRCA subjects. The reference panel includes antibodies of high- and low-affinity with binding specificity to neutralizing and non-neutralizing erythropoietin epitopes. The subclass of human antibodies in this reference panel includes an IgG1, IgG2, and IgG4, as well as an IgM isotype. This antibody panel could help select appropriate immunogenicity assays, guide validation, and monitor assay performance

  13. TSOL18 Vaccine Antigen of Taenia solium: Development of Monoclonal Antibodies and Field Testing of the Vaccine in Cameroon

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    Assana, E.


    lack of knowledge of the taeniasis-cysticercosis complex and the absence of a pig pen in the household were associated with pig cysticercosis. Chapter 3 reports the investigations that were undertaken to characterise whether the principal antibody specificities raised by TSOL18 in pigs were against linear or conformational determinants. TSOL18 was expressed in two truncated forms representing either the amino terminal portion or the carboxy terminal portion, with the two truncations overlapping in sequence by 25 amino acids. The original protein (designated TSOL18N— and the two truncations (TSOL18N—-1 and TSOL18N—-2 were used in inhibition ELISA to determine their ability to inhibit the binding of protective pig antibodies to TSOL18. TSOL18N— was shown to be capable of completely inhibiting the binding of pig anti-TSOL18N— antibodies to TSOL18N— in ELISA. However, neither TSOL18N—-1 nor TSOL18N—-2, either alone or combined, was capable of inhibiting any detectable amount of reactivity of pig anti-TSOL18N— antibodies with TSOL18N—. It is concluded that the dominant antibody specificities, and likely the host-protective specificities, of TSOL18 are conformational epitopes. Chapter 4 describes the development of an antibody detection test for the specific diagnosis of porcine cysticercosis. A fraction with a major band of 14 kDa was obtained from crude cyst fluid (CF of T. solium cysticerci by 2-step chromatography. A first fraction isolated by gel filtration was purified using an anion exchange column on High Performance Liquid Chromatography (HPLC. Evaluation of the analytic sensitivity of this fraction (F3 was carried out in an antibody detection enzyme-linked immunosorbent assay (Ab-ELISA-F3 using serum samples from pigs experimentally infected with different doses of T. solium eggs. The cross-reactivity of F3 was evaluated with serum samples from pigs that were naturally or experimentally infected with Taenia hydatigena, Taenia saginata asiatica

  14. Metrics for antibody therapeutics development. (United States)

    Reichert, Janice M


    A wide variety of full-size monoclonal antibodies (mAbs) and therapeutics derived from alternative antibody formats can be produced through genetic and biological engineering techniques. These molecules are now filling the preclinical and clinical pipelines of every major pharmaceutical company and many biotechnology firms. Metrics for the development of antibody therapeutics, including averages for the number of candidates entering clinical study and development phase lengths for mAbs approved in the United States, were derived from analysis of a dataset of over 600 therapeutic mAbs that entered clinical study sponsored, at least in part, by commercial firms. The results presented provide an overview of the field and context for the evaluation of on-going and prospective mAb development programs. The expansion of therapeutic antibody use through supplemental marketing approvals and the increase in the study of therapeutics derived from alternative antibody formats are discussed.

  15. Development of a rapid agglutination latex test for diagnosis of enteropathogenic and enterohemorrhagic Escherichia coli infection in developing world: defining the biomarker, antibody and method.

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    Letícia B Rocha


    Full Text Available Enteropathogenic and enterohemorrhagic Escherichia coli (EPEC/EHEC are human intestinal pathogens responsible for diarrhea in both developing and industrialized countries. In research laboratories, EPEC and EHEC are defined on the basis of their pathogenic features; nevertheless, their identification in routine laboratories is expensive and laborious. Therefore, the aim of the present work was to develop a rapid and simple assay for EPEC/EHEC detection. Accordingly, the EPEC/EHEC-secreted proteins EspA and EspB were chosen as target antigens.First, we investigated the ideal conditions for EspA/EspB production/secretion by ELISA in a collection of EPEC/EHEC strains after cultivating bacterial isolates in Dulbecco's modified Eagle's medium (DMEM or DMEM containing 1% tryptone or HEp-2 cells-preconditioned DMEM, employing either anti-EspA/anti-EspB polyclonal or monoclonal antibodies developed and characterized herein. Subsequently, a rapid agglutination latex test (RALT was developed and tested with the same collection of bacterial isolates.EspB was defined as a biomarker and its corresponding monoclonal antibody as the tool for EPEC/EHEC diagnosis; the production of EspB was better in DMEM medium. RALT assay has the sensitivity and specificity required for high-impact diagnosis of neglected diseases in the developing world.RALT assay described herein can be considered an alternative assay for diarrhea diagnosis in low-income countries since it achieved 97% sensitivity, 98% specificity and 97% efficiency.

  16. Development and validation of a point-of-care test for detecting hantavirus antibodies in human and rodent samples. (United States)

    Koishi, Andrea Cristine; Aoki, Mateus Nóbrega; Jorge, Taissa Ricciardi; Suzukawa, Andréia Akemi; Zanluca, Camila; Levis, Silvana; Duarte Dos Santos, Claudia Nunes


    Hantaviruses are etiologic agents of a zoonotic disease transmitted mainly from wild rodents to humans, causing Hemorrhagic Fever with Renal Syndrome in Eurasia and the Hantavirus Cardiopulmonary Syndrome in the Americas (HCPS), reaching a lethality rate of 40% in Brazil. Hantavirus diagnostic and seroprevalence are often based on the presence of IgM and IgG antibodies against the virus. Here we propose a rapid test assay able to identify hantavirus antibodies with sensibility and specificity similar to ELISA assays. We analyzed five groups of samples, including healthy human population and small mammals of endemic areas, suspected cases of HCPS, patients with non-related infections and a serum panel from a different geographical region. The test presented good rates of sensibility (87-100%) and specificity (97-100%) for all groups, being a promising tool suitable for both rodent and human hantavirus epidemiological surveys.

  17. [Development of new approaches to standartization of enzyme immunoassay test systems for detection of antibodies to respiratory syncytial virus using electron microscopy and monoclonal antibodies]. (United States)

    Krivitskaia, V Z; Sirotkin, A K; Samoĭlovich, M P; Sominina, A A


    Respiratory syncytial virus (RSV), strain Long, was purified through 20-60% sucrose gradient. The virions from different sucrose density zones were tested by ELISA for reactivity with monoclonal antibodies (MAB) to F- (MAB 9C5) and N- (MAB 8B10) proteins of RSV. Comparative study of the same patterns of RSV by electron microscopy after negative staining showed a close relationship between the virion morphology and MAB binding in ELISA. MAB 9C5 were highly reactive with the surface domains of both mature RSV virions and "empty" virion envelopes without formed inner nucleocapsid structures. MAB 8B10 reacted well only with mature virions with completely assembled nucleocapsids. These MAB failed to reorganize the N-protein epitope of immature and destroyed virions, which indicated a conformation dependence of the 8B10 binding site. For practical purposes, MAB tests can be used to determine the RSV patterns, which can be used in ELISA for serologic diagnosis of RSV infection. Testing with these MAB demonstrate the stability of RSV to extreme exposures (lyophilization, storage, heating), which is important for creation of sensitive ELISA test systems and their standardization.

  18. Development of a Rapid Agglutination Latex Test for Diagnosis of Enteropathogenic and Enterohemorrhagic Escherichia coli Infection in Developing World: Defining the Biomarker, Antibody and Method (United States)

    Munhoz, Danielle D.; Cardoso, Lucas T. A.; Luz, Daniela E.; Andrade, Fernanda B.; Horton, Denise S. P. Q.; Elias, Waldir P.; Piazza, Roxane M. F.


    Background Enteropathogenic and enterohemorrhagic Escherichia coli (EPEC/EHEC) are human intestinal pathogens responsible for diarrhea in both developing and industrialized countries. In research laboratories, EPEC and EHEC are defined on the basis of their pathogenic features; nevertheless, their identification in routine laboratories is expensive and laborious. Therefore, the aim of the present work was to develop a rapid and simple assay for EPEC/EHEC detection. Accordingly, the EPEC/EHEC-secreted proteins EspA and EspB were chosen as target antigens. Methodology First, we investigated the ideal conditions for EspA/EspB production/secretion by ELISA in a collection of EPEC/EHEC strains after cultivating bacterial isolates in Dulbecco’s modified Eagle’s medium (DMEM) or DMEM containing 1% tryptone or HEp-2 cells-preconditioned DMEM, employing either anti-EspA/anti-EspB polyclonal or monoclonal antibodies developed and characterized herein. Subsequently, a rapid agglutination latex test (RALT) was developed and tested with the same collection of bacterial isolates. Principal findings EspB was defined as a biomarker and its corresponding monoclonal antibody as the tool for EPEC/EHEC diagnosis; the production of EspB was better in DMEM medium. RALT assay has the sensitivity and specificity required for high-impact diagnosis of neglected diseases in the developing world. Conclusion RALT assay described herein can be considered an alternative assay for diarrhea diagnosis in low-income countries since it achieved 97% sensitivity, 98% specificity and 97% efficiency. PMID:25254981

  19. A protein-conjugate approach to develop a monoclonal antibody-based antigen detection test for the diagnosis of human brucellosis. (United States)

    Patra, Kailash P; Saito, Mayuko; Atluri, Vidya L; Rolán, Hortensia G; Young, Briana; Kerrinnes, Tobias; Smits, Henk; Ricaldi, Jessica N; Gotuzzo, Eduardo; Gilman, Robert H; Tsolis, Renee M; Vinetz, Joseph M


    Human brucellosis is most commonly diagnosed by serology based on agglutination of fixed Brucella abortus as antigen. Nucleic acid amplification techniques have not proven capable of reproducibly and sensitively demonstrating the presence of Brucella DNA in clinical specimens. We sought to optimize a monoclonal antibody-based assay to detect Brucella melitensis lipopolysaccharide in blood by conjugating B. melitensis LPS to keyhole limpet hemocyanin, an immunogenic protein carrier to maximize IgG affinity of monoclonal antibodies. A panel of specific of monoclonal antibodies was obtained that recognized both B. melitensis and B. abortus lipopolysaccharide epitopes. An antigen capture assay was developed that detected B. melitensis in the blood of experimentally infected mice and, in a pilot study, in naturally infected Peruvian subjects. As a proof of principle, a majority (7/10) of the patients with positive blood cultures had B. melitensis lipopolysaccharide detected in the initial blood specimen obtained. One of 10 patients with relapsed brucellosis and negative blood culture had a positive serum antigen test. No seronegative/blood culture negative patients had a positive serum antigen test. Analysis of the pair of monoclonal antibodies (2D1, 2E8) used in the capture ELISA for potential cross-reactivity in the detection of lipopolysaccharides of E. coli O157:H7 and Yersinia enterocolitica O9 showed specificity for Brucella lipopolysaccharide. This new approach to develop antigen-detection monoclonal antibodies against a T cell-independent polysaccharide antigen based on immunogenic protein conjugation may lead to the production of improved rapid point-of-care-deployable assays for the diagnosis of brucellosis and other infectious diseases.

  20. 21 CFR 866.3290 - Gonococcal antibody test (GAT). (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gonococcal antibody test (GAT). 866.3290 Section... antibody test (GAT). (a) Identification. A gonococcal antibody test (GAT) is an in vitro device that..., indirect fluorescent antibody, or radioimmunoassay, antibodies to Neisseria gonorrhoeae in sera...

  1. Novel indirect fluorescent antibody test for Lyme disease. (United States)

    Chambers, M A; Swango, L J; Wright, J C


    An indirect fluorescent antibody (IFA) test was developed using a novel format of Borrelia burgdorferi organisms adhered to a monolayer of cultured endothelial cells derived from an equine tumor. Sensitivity and specificity of the new IFA test for detecting anti-B, burgdorferi antibodies were evaluated using sera from dogs inoculated with live B. burgdorferi or vaccinated with B. burgdorferi bacterin or leptobacterins and from unvaccinated specific-pathogen-free (SPF) dogs. To compare the new IFA test with existing tests, serum samples were submitted to independent laboratories to be tested by enzyme-linked immunosorbent assay (ELISA) and a traditional IFA test. Samples were also tested with 2 commercially available membrane-bound ELISA kits. Both Borrelia-inoculated dogs and dogs vaccinated with B. burgdorferi bacterin developed levels of antibody detectable by the new IFA test. Dogs vaccinated with a combination canine vaccine or leptobacterin for food animal use developed detectable levels of antibody against Leptospira but remained seronegative for Borrelia by the new IFA test, as did the unvaccinated SPF dogs. The new IFA test was sensitive, detecting antibodies against B. burgdorferi as early as 7 days postinoculation. It was also specific, showing no cross-reactivity with anti-Leptospira antibodies induced by vaccination with leptobacterins. The new IFA test compared favorably with both the standardized traditional IFA test and ELISA. Results from both membrane-bound ELISA kits were not consistent when compared with each other or with the new IFA test. The new IFA test had low nonspecific fluorescence, which made it easier to evaluate and reduced the human error and variability of test results.

  2. Heparin-Induced Thrombocytopenia Antibody Test (United States)

    ... Global Sites Search Help? Heparin-induced Thrombocytopenia PF4 Antibody Share this page: Was this page helpful? Also known as: Heparin-PF4 Antibody; HIT Antibody; HIT PF4 Antibody; Heparin Induced Antibody; ...

  3. DARPA Antibody Technology Program Standardized Test Bed for Antibody Characterization: Characterization of an MS2 ScFv Antibody (United States)



  4. Development and application of an indirect ELISA test for the detection of antibodies to Mycoplasma crocodyli infection in crocodiles (Crocodylus niloticus). (United States)

    Dawo, Fufa; Mohan, Krishna


    Non-availability of a standardized rapid serodiagnostic test for quick and accurate diagnosis of Mycoplasma crocodyli (M. crocodyli) infection in crocodiles was the underlining reason for conducting the present study. An indirect enzyme-linked immunosorbent assay (iELISA) for the detection of antibodies (Ab) to M. crocodyli infection in crocodile sera was developed using sonicated antigen (Ag) and anti-crocodile conjugate. The iELISA test was optimised with different reagents and at different steps. A cut-off value of percent positive greater than or equal to 53.47% resulted in an estimated sensitivity and specificity of 85.67 and 100%, respectively. The developed iELISA could be used for detection of Abs to M. crocodyli infection in crocodiles and may enable to understand the transmission of the disease.

  5. Serum Treponema IgM Antibody Test for Syphilis Diagnosis

    Institute of Scientific and Technical Information of China (English)

    郑占才; 张荣富; 溪茜


    Objective: To evaluate the clinical utility of testing serum anti-treponema pallidum IgM antibody in the diagnosis of syphilis patients. Methods: Seventy-two cases of syphilis were tested for specific IgM antibody with ELISA, and the results were compared with RPR and TPPA.Results: The sensitivity of IgM antibody was 73.3 %(11/15) in primary syphilis, 88.9% (16/18) in sec-ondary syphilis, and there was no significant differ-ence between these values (x2=1.6363, P>0.10). The sensitivity of IgM antibody in diagnosing latent syphi-lis was only 26.1% (6/23), much lower than the detec-tion rate in symptomatic earlv svDhilis (x2=17.6189. P<0.005). RPR and TPPA were both 100% sensitive in latent and early symptomatic syphilis. Two were posi,five for IgM in the 16 cases who had received regular treatments 2 to 24 months before enrolled.Conclusions: Specific IgM antibody detection doees not appear superior to RPR and TPPA in diagnosing primary syphilis. The diagnosis of latent syphilis should mainly rely on RPR and TPPA, since there are low titers of IgM antibody at that stage. IgM antibody testing alone should not be recommended for monitor-ing syphilis development or treatment efficacy. Fur-ther studies should be concerned.

  6. An ELISA test for the detection of antibodies to Legionella pneumophila.


    Wreghitt, T. G.; Nagington, J.; Gray, J


    An enzyme-linked immunosorbent assay (ELISA) test has been developed to detect antibodies to Legionella pneumophila serogroup 1. There is good correlation between indirect fluorescent antibody (IFA) and ELISA titres but ELISA is more sensitive.

  7. Development of an ante-mortem diagnostic test for enzootic nasal tumor virus and detection of neutralizing antibodies in host serum. (United States)

    Walsh, Scott R; Stinson, Kevin J; Menzies, Paula I; Wootton, Sarah K


    Enzootic nasal adenocarcinoma (ENA) is a contagious neoplasm of the nasal mucosa of sheep and goats and is associated with enzootic nasal tumour virus (ENTV). As ENA is a common disease in North America and there are no vaccines against ENTV-1, diagnostic tests that can identify infected animals and assist with eradication and disease surveillance efforts are greatly needed. In this study, we endeavoured to develop a novel, non-invasive diagnostic tool that could be used not only to validate clinical signs of ENA but also to detect ENTV-1 infection prior to the onset of disease signs (i.e. pre-clinical diagnosis). Cytology, serology and reverse transcription (RT)-PCR-based diagnostic methods were investigated. Although the cytology-based assay was able to detect ENTV-1 infection in some animals, it had poor sensitivity and specificity and thus was not developed further as an ante-mortem diagnostic method. Three different assays, including ELISA, Western blotting and virus neutralization, were developed to detect the presence of ENTV-1-specific antibodies in sheep serum. Whilst a surprisingly large number of sheep mounted an antibody-mediated immune response against ENTV-1, and in some cases neutralizing, correlation with disease status was poor. In contrast, RT-PCR on RNA extracted from nasal swabs reliably detected exogenous ENTV-1 sequences, did not amplify endogenous ovine betaretroviral sequences, demonstrated high concordance with immunohistochemical staining for ENTV-1 envelope protein, and had perfect sensitivity and specificity. This report describes a practical and highly specific RT-PCR technique for the detection of clinical and pre-clinical ENA that may prove beneficial in future control or eradication programmes.

  8. DARPA Antibody Technology Program Standardized Test Bed for Antibody Characterization: Characterization of an MS2 Human IgG Antibody Produced by AnaptysBio, Inc. (United States)


    ECBC-TR-1339 DARPA ANTIBODY TECHNOLOGY PROGRAM STANDARDIZED TEST BED FOR ANTIBODY...CHARACTERIZATION: CHARACTERIZATION OF AN MS2 HUMAN IGG ANTIBODY PRODUCED BY ANAPTYSBIO, INC. DARPA ATP Standardized Test Bed for Antibody...Characterization: Characterization of an MS2 human IgG antibody produced by AnaptysBio DARPA ATP Standardized Test Bed for Antibody

  9. Development of Antibody Against Sulfamethazine

    Institute of Scientific and Technical Information of China (English)

    LIZi-ying; XUWen-ge; LIUYi-bing; ZHANGLi-ling; GUOWei-zheng; HANShi-quan


    Polyclonal antibodies(PcAbs) against sulfamethazine(SMT) are obtained by immunizing rabbits with SMT-conjugated bovine serum albumin(BSA). The affinity constants (Ka) of the PcAbs are higher than 1×108 and the cross-reactivities with sulfadiazine(SD), sulfaquinoxaline (SQX) are lower than 0.05% (R/A).

  10. Development of syngeneic monoclonal anti-idiotype antibodies to mouse monoclonal anti-asialoglycoprotein receptor antibody.

    Directory of Open Access Journals (Sweden)

    Hirai M


    Full Text Available Anti-idiotype antibodies (Ab2 play an important role in the homeostasis of immune responses and are related to the development and the disease activity of certain autoimmune diseases. The asialoglycoprotein receptor (ASGPR is considered one of the target antigens in the pathogenesis of autoimmune chronic active hepatitis (AIH. We previously developed a mouse monoclonal antibody (clone 8D7 which recognizes rat and human ASGPR. In this study, to help investigate the anti-ASGPR antibody-anti-idiotype antibody network in patients with AIH, we developed a syngeneic mouse monoclonal Ab2 to the 8D7 anti-ASGPR antibody (Ab1. One clone, designated as 3C8, tested positive for specific reactivity to 8D7-Ab1 and did not bind to other irrelevant immunoglobulins. By competitive inhibition assays, the binding of 8D7-Ab1 to liver membrane extracts, i.e., the crude antigen preparation, was inhibited by 3C8-Ab2 in a dose-dependent manner, and the binding of 8D7-Ab1 to 3C8-Ab2 was inhibited by the liver membrane extracts. In the immunohistochemical analysis, 3C8-Ab2 blocked the specific staining of sinusoidal margins of rat hepatocytes by 8D7-Ab1. These results suggest that 3C8 anti-idiotype antibody recognizes the specific idiotypic determinants within the antigen-binding site of 8D7-Ab1.

  11. Development of a competitive ELISA for NS3 antibodies as DIVA test accompanying the novel Disabled Infectious Single Animal (DISA) vaccine for Bluetongue. (United States)

    Tacken, Mirriam G J; Daus, Franz J; Feenstra, Femke; van Gennip, René G P; van Rijn, Piet A


    Recently, we have developed a novel vaccine for Bluetongue named BT Disabled Infectious Single Animal (DISA) vaccine. Due to the lack of non-essential NS3/NS3a protein, BT DISA vaccine is a replicating vaccine, but without the inherent risks of live-attenuated vaccines, such as residual virulence or reversion to virulence by mutations, reassortment with field virus, horizontal spread by vectors and vertical transmission. The immune response induced by BT DISA vaccines is rapidly induced, highly protective and serotype specific which is dependent on the immunodominant and serotype determining VP2 protein. The BT DISA vaccine platform provides the replacement of exclusively VP2 from different serotypes in order to safely formulate multivalent cocktail vaccines. The lack of NS3/NS3a directed antibodies by BT DISA vaccination enables differentiation of infected from vaccinated animals (DIVA principle). A highly conserved immunogenic site corresponding to the late domain was mapped in the N-terminal region of NS3. We here established an NS3-specific competitive ELISA (NS3 cELISA) as serological DIVA test accompanying BT DISA vaccines. To this end, NS3 protein missing putative transmembrane regions was produced in large amounts in bacteria and used as antigen in the NS3 cELISA which was investigated with a variety of sera. The NS3 cELISA displayed a high sensitivity and specificity similar to the commercially available VP7-specific cELISA. Results of previously performed vaccination-challenge trials with BT DISA vaccines clearly demonstrate the DIVA system based on the NS3 cELISA and BT vaccine free of NS3 protein.

  12. Competency development in antibody production in cancer cell biology

    Energy Technology Data Exchange (ETDEWEB)

    Park, M.S.


    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The main objective of this project was to develop a rapid recombinant antibody production technology. To achieve the objective, the authors employed (1) production of recombinant antigens that are important for cell cycle regulation and DNA repair, (2) immunization and specific selection of antibody-producing lymphocytes using the flow cytometry and magnetic bead capturing procedure, (3) construction of single chain antibody library, (4) development of recombinant vectors that target, express, and regulate the expression of intracellular antibodies, and (5) specific inhibition of tumor cell growth in tissue culture. The authors have accomplished (1) optimization of a selection procedure to isolate antigen-specific lymphocytes, (2) optimization of the construction of a single-chain antibody library, and (3) development of a new antibody expression vector for intracellular immunization. The future direction of this research is to continue to test the potential use of the intracellular immunization procedure as a tool to study functions of biological molecules and as an immuno-cancer therapy procedure to inhibit the growth of cancer cells.

  13. Antibody Fragments as Probe in Biosensor Development

    Directory of Open Access Journals (Sweden)

    Serge Muyldermans


    Full Text Available Today’s proteomic analyses are generating increasing numbers of biomarkers, making it essential to possess highly specific probes able to recognize those targets. Antibodies are considered to be the first choice as molecular recognition units due to their target specificity and affinity, which make them excellent probes in biosensor development. However several problems such as difficult directional immobilization, unstable behavior, loss of specificity and steric hindrance, may arise from using these large molecules. Luckily, protein engineering techniques offer designed antibody formats suitable for biomarker analysis. Minimization strategies of antibodies into Fab fragments, scFv or even single-domain antibody fragments like VH, VL or VHHs are reviewed. Not only the size of the probe but also other issues like choice of immobilization tag, type of solid support and probe stability are of critical importance in assay development for biosensing. In this respect, multiple approaches to specifically orient and couple antibody fragments in a generic one-step procedure directly on a biosensor substrate are discussed.

  14. 21 CFR 866.5100 - Antinuclear antibody immunological test system. (United States)


    ... autoimmune disease in which antibodies attack the victim's own tissues), hepatitis (a liver disease... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Antinuclear antibody immunological test system. 866.5100 Section 866.5100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  15. Recent developments in monoclonal antibody radiolabeling techniques

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S.C.; Mease, R.C.


    Monoclonal antibodies (MAbs) have shown the potential to serve as selective carriers of radionuclides to specific in vivo antigens. Accordingly, there has been an intense surge of research activity in an effort to develop and evaluate MAb-based radiopharmaceuticals for tumor imaging (radioimmunoscintigraphy) and therapy (radioimmunotherapy), as well as for diagnosing nonmalignant diseases. A number of problems have recently been identified, related to the MAbs themselves and to radiolabeling techniques, that comprise both the selectivity and the specificity of the in vivo distribution of radiolabeled MAbs. This paper will address some of these issues and primarily discuss recent developments in the techniques for radiolabeling monoclonal antibodies that may help resolve problems related to the poor in vivo stability of the radiolabel and may thus produce improved biodistribution. Even though many issues are identical with therapeutic radionuclides, the discussion will focus mainly on radioimmunoscintigraphic labels. 78 refs., 6 tabs.

  16. Drug Development of Therapeutic Monoclonal Antibodies. (United States)

    Mould, Diane R; Meibohm, Bernd


    Monoclonal antibodies (MAbs) have become a substantial part of many pharmaceutical company portfolios. However, the development process of MAbs for clinical use is quite different than for small-molecule drugs. MAb development programs require careful interdisciplinary evaluations to ensure the pharmacology of both the MAb and the target antigen are well-understood. Selection of appropriate preclinical species must be carefully considered and the potential development of anti-drug antibodies (ADA) during these early studies can limit the value and complicate the performance and possible duration of preclinical studies. In human studies, many of the typical pharmacology studies such as renal or hepatic impairment evaluations may not be needed but the pharmacokinetics and pharmacodynamics of these agents is complex, often necessitating more comprehensive evaluation of clinical data and more complex bioanalytical assays than might be used for small molecules. This paper outlines concerns and strategies for development of MAbs from the early in vitro assessments needed through preclinical and clinical development. This review focuses on how to develop, submit, and comply with regulatory requirements for MAb therapeutics.

  17. Immunoglobulins, antibody repertoire and B cell development. (United States)

    Butler, J E; Zhao, Y; Sinkora, M; Wertz, N; Kacskovics, I


    Swine share with most placental mammals the same five antibody isotypes and same two light chain types. Loci encoding lambda, kappa and Ig heavy chains appear to be organized as they are in other mammals. Swine differ from rodents and primates, but are similar to rabbits in using a single VH family (VH3) to encode their variable heavy chain domain, but not the family used by cattle, another artiodactyl. Distinct from other hoofed mammals and rodents, Ckappa:Clambda usage resembles the 1:1 ratio seen in primates. Since IgG subclasses diversified after speciation, same name subclass homologs do not exist among swine and other mammals unless very closely related. Swine possess six putative IgG subclasses that appear to have diversified by gene duplication and exon shuffle while retaining motifs that can bind to FcgammaRs, FcRn, C1q, protein A and protein G. The epithelial chorial placenta of swine and the precosial nature of their offspring have made piglets excellent models for studies on fetal antibody repertoire development and on the postnatal role of gut colonization, maternal colostrum and neonatal infection on the development of adaptive immunity during the "critical window" of immunological development. This chapter traces the study of the humoral immune system of this species through its various eras of discovery and compiles the results in tables and figures that should be a useful reference for educators and investigators.

  18. Development of Anti-Isoproturon Polyclonal Antibody

    Institute of Scientific and Technical Information of China (English)

    LI Fang-shi; SUN Feng; LIU Xian-jin; CUI Heng-hua


    A competitive enzyme-linked immunosorbent assay (ELISA) suitable for the determination of the urea herbicide isoproturon,3-(4-isopropylphenyl)-1,1-dimethylurea, in food and environmental samples was developed. Two haptens named 1-(3-carboxypropyl)-3-(4-isopropylphenyl)-1-methylurca (hapten 4C) and 1-(5-carboxypentyl)-3-(4-isopropylphenyl)-1-methylurea (hapten 6C) were synthesized. The haptens were coupled to bovine serum albumin (BSA) and ovalbumin(OVA), respectively, using the N-hydroxysuccinimide reaction. The hapten 6C-BSA conjugate was used as the immunogen,with which a high-titer anti-isoproturon polyclonal antibody (pAb) was successfully obtained by immunization of New Zealand white rabbits. The hapten 4C-OVA conjugate was used as coating antigen and a method of the indirect competitive ELISA for isoproturon was established. The haptens were confirmed with TLC, IR, and 1H NMR. The conjugation molar ratios of hapten 4C to OVA and hapten 6C to BSA were 36:1 and 46:1, respectively, as calculated by a UV spectrophotometry.The highest titer of the anti-isoproturon sera determined by a non-competitive indirect ELISA procedure was 1.6×105. The optimal concentrations of the coating antigen and the dilution of the anti-isoproturon sera used in the ELISA were 0.1 mg L-1 and 1.0 × 105, respectively. The concentration of isoproturon that inhibits 50% of antibody-antigen binding (IC50) was 0.07 mg mL-1.The cross-reactivities of six urea herbicides including chlorbromuron, fluometuron, monolinuron were lower than 0.1%. Isoproturon is a small molecule without immune activity and active functional group for attaching to carrier protein. To produce an antibody against isoproturon with high titer and high specificity is the most important step in the development of an immunochemical method for the determination of isoproturon in food and environmental samples. The two haptens synthesized in this study have carboxyl groups and accommodate different lengths of spacer arms, and

  19. Development of a Blocking ELISA Using a Monoclonal Antibody to a Dominant Epitope in Non-Structural Protein 3A of Foot-and-Mouth Disease Virus, as a Matching Test for a Negative-Marker Vaccine (United States)

    Fu, Yuanfang; Li, Pinghua; Cao, Yimei; Wang, Na; Sun, Pu; Shi, Qian; Ji, Xincheng; Bao, Huifang; Li, Dong; Chen, Yingli; Bai, Xingwen; Ma, Xueqing; Zhang, Jing; Lu, Zengjun; Liu, Zaixin


    Foot-and-mouth disease (FMD) is a devastating animal disease. Strategies for differentiation of infected from vaccinated animals (DIVA) remain very important for controlling disease. Development of an epitope-deleted marker vaccine and accompanying diagnostic method will improve the efficiency of DIVA. Here, a monoclonal antibody (Mab) was found to recognize a conserved “AEKNPLE” epitope spanning amino acids 109–115 of non-structural protein (NSP) 3A of foot-and-mouth disease virus (FMDV; O/Tibet/CHA/99 strain), which could be deleted by a reverse-genetic procedure. In addition, a blocking ELISA was developed based on this Mab against NSP 3A, which could serve as a matching test for a negative-marker vaccine. The criterion of this blocking ELISA was determined by detecting panels of sera from different origins. The serum samples with a percentage inhibition (PI) equal or greater than 50% were considered to be from infected animals, and those with <50% PI were considered to be from non-infected animals. This test showed similar performance when compared with other 2 blocking ELISAs based on an anti-NSP 3B Mab. This is the first report of the DIVA test for an NSP antibody based on an Mab against the conserved and predominant “AEKNPLE” epitope in NSP 3A of FMDV. PMID:28107470

  20. DARPA Antibody Technology Program. Standardized Test Bed for Antibody Characterization: Characterization of an MS2 ScFv Antibody Produced by Illumina (United States)


    ECBC-TR-1395 DARPA ANTIBODY TECHNOLOGY PROGRAM STANDARDIZED TEST BED FOR...Thompson James Carney RESEARCH AND TECHNOLOGY DIRECTORATE Candice Warner Melody Zacharko EXCET, INC. Springfield, VA 22151-2110...4. TITLE AND SUBTITLE DARPA Antibody Technology Program Standardized Test Bed for Antibody Characterization: Characterization of an MS2 ScFv

  1. Belgian recommendations on ANA, anti-dsDNA and anti-ENA antibody testing. (United States)

    Van Blerk, M; Bossuyt, X; Humbel, R; Mewis, A; Servais, G; Tomasi, J P; Van Campenhout, C; Van Hoovels, L; Vercammen, M; Damoiseaux, J; Coucke, W; Van de Walle, P


    Autoantibodies to nuclear antigens, i.e. antinuclear antibodies (ANA), antibodies to double-stranded DNA (dsDNA) and extractable nuclear antigens (ENA), are useful as diagnostic markers for a variety of autoimmune diseases. In March 2010, the Belgian national External Quality Assessment Scheme sent a questionnaire on ANA, anti-dsDNA and anti-ENA antibody testing designed by the Dutch EASI (European Autoimmunity Standardization Initiative) team, to all clinical laboratories performing ANA testing. Virtually all laboratories completed the questionnaire (97·7%, 127/130). This paper discusses the results of this questionnaire and provides valuable information on the state-of-the-art of ANA, anti-dsDNA and anti-ENA antibody testing as practiced in the Belgian laboratories. In addition, this work presents practical recommendations developed by the members of the advisory board of the scheme as a result of the outcome of this study.

  2. 21 CFR 866.5110 - Antiparietal antibody immunological test system. (United States)


    ...), atrophic gastritis (inflammation of the stomach), and autoimmune connective tissue diseases (diseases... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Antiparietal antibody immunological test system. 866.5110 Section 866.5110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  3. 一种基于量子点检测抗CCP抗体的免疫荧光层析法%Development of an Immunochromatographic Test Strip for the Detection of Anti-CCP Antibody Based on Quantum Dots

    Institute of Scientific and Technical Information of China (English)

    郭利宁; 何红秋


    抗环瓜氨酸多肽(cyclic citrullinated peptide,CCP)抗体是类风湿关节炎(rheumatoid arthritis,RA)早期诊断的重要生物标志物.为了实现对RA的早期诊断,本研究建立了一种基于CdTe量子点标记技术检测抗CCP抗体的免疫荧光层析法.将CCP多肽与小牛血清白蛋白(bovine serum albumin,BSA)连接,再将CCP-BSA和羊抗鼠IgG分别在硝酸纤维素膜(nitrocellulose membrane,NC膜)上划线,作为检测线(test line,T线)和质控线(control line,C线).制备量子点并在量子点上标记鼠抗人IgG,喷在玻璃纤维上并烘干,最后组装大卡、切割并封装制成检测试纸条.应用该试纸条检测了RA患者及健康人血清临床样本200份,以酶联免疫吸附测定法(enzyme-linked immunosorbent assay,ELISA)为对照,计算免疫荧光层析法的检测灵敏度和特异性.结果显示,建立的量子点免疫荧光层析试纸条检测抗CCP抗体的灵敏度为97.5%,特异性为95.8%.该方法操作简单、快速,可实现床旁检测(point-of-care testing,POCT),能应用于RA的早期诊断.%Anti-cyclic citrullinated peptide antibody ( anti-CCP antibody) is an important biomarker for early detection of rheumatoid arthritis ( RA). For clinical diagnosis of RA in the early stage, an immunochromatographic test strip for anti-CCP antibody detection was developed based on quantum dots. First, CCP was linked to bovine serum albumin (BSA) ; and then, the CCP-BSA and goat anti-mouse IgG were dotted on the nitrocellulose membrane as test line ( T line) and control line ( C line) , respectively. Subsequently, quantum dots solution was prepared and conjugated to the mouse anti-human IgG antibody; further more, the marked quantum dots were sprayed to the glass fibers and dried. Last, all components of immunochromatographic test strip were assembled, cut and packaged. The test strip has been applied to the detection of 200 clinic serum samples from RA patients and healthy people, and the sensitivity

  4. Rapid, whole blood diagnostic test for detecting anti-hantavirus antibody in rats. (United States)

    Amada, Takako; Yoshimatsu, Kumiko; Yasuda, Shumpei P; Shimizu, Kenta; Koma, Takaaki; Hayashimoto, Nobuhito; Gamage, Chandika D; Nishio, Sanae; Takakura, Akira; Arikawa, Jiro


    Hantavirus is a causative agent of rodent-borne viral zoonoses, hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome. Seoul virus (SEOV) is a causative agent of urban and laboratory rat-associated HFRS worldwide. Surveillance of rodents has been done mainly by serological detection of hantavirus-specific antibodies by enzyme linked immunosorbent assay (ELISA) and immunofluorescent antibody assay (IFA). An immunochromatographic (ICG) test was developed with the N-terminal 103 amino acids of nucleocapsid protein of Hantaan virus expressed by Escherichia coli as an antigen to detect IgG antibody specific to hantavirus in sera from Rattus sp. animals. Antibody-detecting sensitivity of the ICG test was the same as that of ELISA and about 100-times higher than that of IFA. Overall sensitivities and specificities of the ICG test in comparison to ELISA and IFA for sera from 192 urban rats and 123 laboratory rats were 99.3% and 100%, respectively. Diluted whole blood samples without separation could be used for the ICG test. The ICG test enabled detection of antibodies to SEOV, Hantaan, Dobrava/Belgrade, and Thailand viruses, which are causative agents of HFRS throughout Eurasia. The ICG test is a rapid, simple and safe method for diagnosis of SEOV infection in rats.

  5. Development of monoclonal antibodies that recognize Treponema pallidum.


    Saunders, J M; Folds, J D


    We developed a panel of monoclonal antibodies to Treponema pallidum (Nichols) antigens, some of which recognize treponemal antigens on T. pallidum (Nichols), T. pallidum strain 14, and Treponema phagedenis biotype Reiter. The antibodies were detected by either an enzyme-linked immunosorbent assay or a radioimmunoassay.

  6. Developing recombinant antibodies for biomarker detection

    Energy Technology Data Exchange (ETDEWEB)

    Baird, Cheryl L.; Fischer, Christopher J.; Pefaur, Noah B.; Miller, Keith D.; Kagen, Jacob; Srivastava, Sudhir; Rodland, Karin D.


    Monoclonal antibodies (mAbs) have an essential role in biomarker validation and diagnostic assays. A barrier to pursuing these applications is the reliance on immunization and hybridomas to produce mAbs, which is time-consuming and may not yield the desired mAb. We recommend a process flow for affinity reagent production that utilizes combinatorial protein display systems (eg, yeast surface display or phage display) rather than hybridomas. These systems link a selectable phenotype-binding conferred by an antibody fragment-with a means for recovering the encoding gene. Recombinant libraries obtained from immunizations can produce high-affinity antibodies (<10 nM) more quickly than other methods. Non-immune libraries provide an alternate route when immunizations are not possible, or when suitable mAbs are not recovered from an immune library. Directed molecular evolution (DME) is an integral part of optimizing mAbs obtained from combinatorial protein display, but can also be used on hybridoma-derived mAbs. Variants can easily be obtained and screened to increase the affinity of the parent mAb (affinity maturation). We discuss examples where DME has been used to tailor affinity reagents to specific applications. Combinatorial protein display also provides an accessible method for identifying antibody pairs, which are necessary for sandwich-type diagnostic assays.

  7. [Evaluation of latex agglutination test for anti-treponemal antibody in comparison with chemical luminescence tests]. (United States)

    Watanabe, Naomi; Nagatomo, Ritsuko; Okubo, Shigeo; Yokota, Hiromitsu; Ikeda, Hitoshi; Yatomi, Yutaka


    The performance of a latex agglutination test (Mediace TPLA) in the detection of anti-treponemal antibody was evaluated in comparison with chemical luminescence tests (LumipulsII-N and Architect TPAb) in 346 cases. Anti-treponemal antibody was further determined by immunochromatography and immunoblotting tests and additionally evaluated by a serological test for syphilis with lipoidal antigens. The total concordance rate between the latex agglutination test and chemical luminescence tests ranged from 96% to 97%: the positive concordance rate ranged from 96% to 97%, and the negative concordance rate, from 97% to 98%. The latex agglutination test showed two false positive cases, and each chemical luminescence test showed two false positive cases, respectively. In eight cases, only the latex agglutination test showed negative results; all specimens contained anti-treponemal antibodies. However, none of these was considered to be a false positive and each was treated as syphilis based on the results of confirmatory analysis with immunochromatography and immunoblotting tests and a serological test for syphilis. The discordant results in the latex agglutination test and chemical luminescence tests may be caused by the different antigenisity of each test. With detailed analysis of those sera treated as syphilis, each specimen was found to contain various antibodies against syphilitic antigens, suggesting that there was a different specificity of native and recombinant antigens. Based on the present results for the comparison between the latex agglutination test and chemical luminescence tests, it was considered that further investigation is necessary to clarify the anti-treponemal antibody profile of syphilis at the disease stage.

  8. 21 CFR 864.9175 - Automated blood grouping and antibody test system. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Automated blood grouping and antibody test system... Manufacture Blood and Blood Products § 864.9175 Automated blood grouping and antibody test system. (a) Identification. An automated blood grouping and antibody test system is a device used to group erythrocytes...

  9. [Comparison of eight screening tests for ant-HCV antibody]. (United States)

    Deguchi, Matsuo; Kagita, Masanori; Yamashita, Naoko; Nakano, Takasi; Tahara, Kazuko; Asari, Seishi; Iwatani, Yoshinori


    We compared eight HCV screening tests for detection of anti-HCV antibody; Ortho Quick Chaser HCV Ab (QC), Ortho HCV Ab ELISA III (ELISA), Ortho HVC Ab PA test III (PA), Lumipulse II Ortho HCV (LUMI), IMx HCV.DAINAPACKII (IMx), ARCHITECT HCV (ARCH), Immucheck.F-HCV C50 Ab (Immu), RANREAM HCV Ab Ex II (RAN). Sera from six hundred patients were examined by these eight screening tests. The positive rates of the eight screening tests were from 9.0% to 13.2%. Forty-five sera showed discrepant results between the eight screening tests, and about half of them showed weak positive reaction and/or false positive. Twenty-five of the forty-five sera were negative for ant-HCV antibody in the CHIRON RIBA III confirmatory test, and forty-four of them were negative for HCV-RNA in the PCR method. The agreement rates between the two reagents were from 95.5% to 99.2%, but were not always high between the two reagents that used similar antigen. The specificities and sensitivities evaluated by using the RIBA III confirmatory test were excellent in ELISA, LUMI, IMx, ARCH and Immu. Three BBI seroconversion panels were used to compare the positive readings in the initial stage of HCV infection by eight screening tests. ELISA and ARCH showed the earliest positive readings, and then IMx, LUMI = RAN, PA, QC and Immu in this order. These findings indicate that ELISA and ARCH were the most excellent in the sensitivity, specificity and early diagnosis of HCV infection. However, we must pay attention to the weak positive reaction in the screening tests, because there is a possibility of "false positive".

  10. Antibody (United States)

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

  11. Development and characterization of a novel anti-ceramide antibody. (United States)

    Krishnamurthy, Kannan; Dasgupta, Somsankar; Bieberich, Erhard


    Ceramide is emerging as a key sphingolipid that regulates a variety of cellular processes. To facilitate the study of ceramide localization and its interaction with cellular proteins, we have developed a novel antibody against ceramide. Our results indicate that the antibody (rabbit IgG) specifically recognizes ceramide in lipid overlay assays and detects ceramide species with different fatty acid chain lengths that include C2, C8, C16, C18, C20, and C24. The new antibody was compared with the commercially available anti-ceramide antibody (mouse IgM) in immunocytochemistry experiments to study the localization of ceramide. Although both antibodies stain the same regions on the cell membrane, the rabbit IgG reveals the distribution of ceramide in compartments that are not well identified with the commercially available antibody. In addition to staining of ceramide in protrusions of the plasma membrane, the rabbit IgG also detects ceramide in the Golgi apparatus. Pharmacological depletion or increase of ceramide levels results in a corresponding change in staining intensity, confirming the specificity of the antibody. These results indicate that the rabbit IgG is a suitable antibody to determine the localization of ceramide and its interaction with proteins by immunocytochemistry.

  12. Comparative Studies on Detection of Antibodies against Infectious Bursal Disease Virus with Test Strips and Agar Gel Immunodiffusion Method

    Institute of Scientific and Technical Information of China (English)

    Jinliang ZHANG; Wentong ZHANG; Sishun HU; Dingren BI; Xiliang WANG; Yuncai XIAO


    [Objective] This study aimed to compare the detection results of antibodies against infectious bursal disease virus with test strips and agar gel immunodiffusion method. [Method] Antibodies against infectious bursal disease virus in chicken serum were detected using test strips developed in our laboratory, and the results were comparad~with that using traditional agar diffusion method. [Result] The comparative study of the two methods showed that the sensitivity of test strips was eight times over agar gel immunodiffusion; test strips showed higher detection rate in the deter- mination test of 216 clinical samples, with high specificity, easy preservation, and simple and rapid operation, thereby being more suitable for the monitoring of clinical antibodies. [Conclusion] Test strips could replace the existing serological methods, having great promotion and application value in antibody monitoring.

  13. Interim Guidance for Interpretation of Zika Virus Antibody Test Results. (United States)

    Rabe, Ingrid B; Staples, J Erin; Villanueva, Julie; Hummel, Kimberly B; Johnson, Jeffrey A; Rose, Laura; Hills, Susan; Wasley, Annemarie; Fischer, Marc; Powers, Ann M


    Zika virus is a single-stranded RNA virus in the genus Flavivirus and is closely related to dengue, West Nile, Japanese encephalitis, and yellow fever viruses (1,2). Among flaviviruses, Zika and dengue virus share similar symptoms of infection, transmission cycles, and geographic distribution. Diagnostic testing for Zika virus infection can be accomplished using both molecular and serologic methods. For persons with suspected Zika virus disease, a positive real-time reverse transcription-polymerase chain reaction (rRT-PCR) result confirms Zika virus infection, but a negative rRT-PCR result does not exclude infection (3-7). In these cases, immunoglobulin (Ig) M and neutralizing antibody testing can identify additional recent Zika virus infections (6,7). However, Zika virus antibody test results can be difficult to interpret because of cross-reactivity with other flaviviruses, which can preclude identification of the specific infecting virus, especially when the person previously was infected with or vaccinated against a related flavivirus (8). This is important because the results of Zika and dengue virus testing will guide clinical management. Pregnant women with laboratory evidence of Zika virus infection should be evaluated and managed for possible adverse pregnancy outcomes and be reported to the U.S. Zika Pregnancy Registry or the Puerto Rico Zika Active Pregnancy Surveillance System for clinical follow-up (9,10). All patients with clinically suspected dengue should have proper management to reduce the risk for hemorrhage and shock (11). If serologic testing indicates recent flavivirus infection that could be caused by either Zika or dengue virus, patients should be clinically managed for both infections because they might have been infected with either virus.

  14. EBF recommendation for stability testing of anti-drug antibodies; lessons learned from anti-vaccine antibody stability studies. (United States)

    Pihl, Susanne; Michaut, Lydia; Hendriks, Jenny; Loebbert, Ralf; Ryding, Janka; Nemansky, Martin; Vermet, Laurent; Companjen, Arjen


    Long- and short-term stability testing of the analyte is one of the key parameters in bioanalytical method validation in support of pharmacokinetics. However, for immunogenicity testing, the scientific rationale for long- and short-term stability testing on quality control samples most often spiked with polyclonal antibody raised in a different species should be questioned. Therefore, the European Bioanalysis Forum (EBF) formed a Topic Team to discuss the scientific rationale for stability testing of anti-drug antibodies (ADAs). A review of EBF member companies' experience on ADA stability and on anti-vaccine antibodies from vaccine projects was the basis of this discussion. EBF recommends to perform short-term stability testing of the positive control, but not to perform long-term stability testing of ADAs in nonclinical and clinical studies.

  15. Development and standardization of multiplexed antibody microarrays for use in quantitative proteomics. (United States)

    Perlee, Lt; Christiansen, J; Dondero, R; Grimwade, B; Lejnine, S; Mullenix, M; Shao, W; Sorette, M; Tchernev, Vt; Patel, Dd; Kingsmore, Sf


    BACKGROUND: Quantitative proteomics is an emerging field that encompasses multiplexed measurement of many known proteins in groups of experimental samples in order to identify differences between groups. Antibody arrays are a novel technology that is increasingly being used for quantitative proteomics studies due to highly multiplexed content, scalability, matrix flexibility and economy of sample consumption. Key applications of antibody arrays in quantitative proteomics studies are identification of novel diagnostic assays, biomarker discovery in trials of new drugs, and validation of qualitative proteomics discoveries. These applications require performance benchmarking, standardization and specification. RESULTS: Six dual-antibody, sandwich immunoassay arrays that measure 170 serum or plasma proteins were developed and experimental procedures refined in more than thirty quantitative proteomics studies. This report provides detailed information and specification for manufacture, qualification, assay automation, performance, assay validation and data processing for antibody arrays in large scale quantitative proteomics studies. CONCLUSION: The present report describes development of first generation standards for antibody arrays in quantitative proteomics. Specifically, it describes the requirements of a comprehensive validation program to identify and minimize antibody cross reaction under highly multiplexed conditions; provides the rationale for the application of standardized statistical approaches to manage the data output of highly replicated assays; defines design requirements for controls to normalize sample replicate measurements; emphasizes the importance of stringent quality control testing of reagents and antibody microarrays; recommends the use of real-time monitors to evaluate sensitivity, dynamic range and platform precision; and presents survey procedures to reveal the significance of biomarker findings.

  16. Development and standardization of multiplexed antibody microarrays for use in quantitative proteomics

    Directory of Open Access Journals (Sweden)

    Sorette M


    Full Text Available Abstract Background Quantitative proteomics is an emerging field that encompasses multiplexed measurement of many known proteins in groups of experimental samples in order to identify differences between groups. Antibody arrays are a novel technology that is increasingly being used for quantitative proteomics studies due to highly multiplexed content, scalability, matrix flexibility and economy of sample consumption. Key applications of antibody arrays in quantitative proteomics studies are identification of novel diagnostic assays, biomarker discovery in trials of new drugs, and validation of qualitative proteomics discoveries. These applications require performance benchmarking, standardization and specification. Results Six dual-antibody, sandwich immunoassay arrays that measure 170 serum or plasma proteins were developed and experimental procedures refined in more than thirty quantitative proteomics studies. This report provides detailed information and specification for manufacture, qualification, assay automation, performance, assay validation and data processing for antibody arrays in large scale quantitative proteomics studies. Conclusion The present report describes development of first generation standards for antibody arrays in quantitative proteomics. Specifically, it describes the requirements of a comprehensive validation program to identify and minimize antibody cross reaction under highly multiplexed conditions; provides the rationale for the application of standardized statistical approaches to manage the data output of highly replicated assays; defines design requirements for controls to normalize sample replicate measurements; emphasizes the importance of stringent quality control testing of reagents and antibody microarrays; recommends the use of real-time monitors to evaluate sensitivity, dynamic range and platform precision; and presents survey procedures to reveal the significance of biomarker findings.

  17. Artificial antigen synthesis and the development of polyclonal antibody-based immunoassay for citreoviridin determination. (United States)

    Zhuang, Zhen Hong; Que, Shan Jin; Gao, Yue Ming; Yuan, Jun; Ye, Zhou; Du, Min; Lin, Guang Mei; Liu, Li Cai; Wang, Shi Hua


    Citreoviridin, a mycotoxin produced by Penicillium citreonigrum is a common contaminant of wide range of agri-products and detrimental to human and animal health. Therefore it is important to develop a rapid, sensitive, and specific immunoassay for citreoviridin detection. In this study, polyclonal antibody against citreoviridin was developed. For the preparation of citreoviridin-bovine serum albumin conjugate (CIT-BSA), hydroxyl groups on adjacent carbon atoms were oxidized by sodium periodate, so the product with reactive aldehyde residues was suitable for coupling with amine. Anti-citreoviridin polyclonal antibody was prepared by immunizing mice with CIT-BSA conjugate. The specificity and sensitivity of the polyclonal antibody was determined by indirect competitive ELISA. Results showed that the IC50 value of the polyclonal antibody was 0.56 μg/mL and no cross-reactivity was found between antiserum and other mycotoxins used in the experiment. The citreoviridin recovery rates by this polyclonal antibody were calculated through rice powder spiked by artificial citreoviridin. The recovery rates ranged were found from 70.5 ± 0.08 % to 94.7 ± 0.09% for inter-assay, and from 77.5 ± 0.04% to 95.4 ± 0.18% for intra-assay, which indicated that this polyclonal antibody could detect trace amount of CIT from the tested samples. Consequently, this study provided a specific and sensitive anti-citreoviridin polyclonal antibody, which made the determination of citreoviridin easier, quicker, and more accurate.

  18. Clinical utility of antinuclear antibody tests in children

    Directory of Open Access Journals (Sweden)

    Kickingbird Lauren M


    Full Text Available Abstract Background Antinuclear antibody (ANA tests are frequently used to screen children for chronic inflammatory diseases such as systemic lupus erythematosus (SLE. However, the diagnostic utility of this test is limited because of the large number of healthy children who have low-titer positive tests. We sought to determine the clinical utility of ANA tests in screening children for rheumatic disease and to determine whether there are specific signs or symptoms that enhance the clinical utility of ANA tests in children. Methods We undertook a retrospective analysis of 509 new patient referrals. Charts of patients referred because of results of ANA testing were selected for further analysis. Children with JRA, SLE, and other conditions were compared using demographic data, chief complaints at the time of presentation, and ANA titers. Results One hundred ten patients were referred because of an ANA test interpreted as positive. Ten patients were subsequently diagnosed with SLE. In addition, we identified one patient with mixed connective tissue disease, and an additional child with idiopathic Raynaud's phenomenon. Eighteen children of the children referred for a positive ANA test had juvenile rheumatoid arthritis (JRA. Another 80 children with positive ANA tests were identified, the majority of whom (n = 39, 49% had musculoskeletal pain syndromes. Neither the presence nor the titer of ANA served to distinguish children with JRA from children with other musculoskeletal conditions. Children with JRA were readily identified on the basis of the history and physical examination. Children with SLE were therefore compared with children with positive ANA tests who did not have JRA, designated the "comparison group." Non-urticarial rash was more common in children with SLE than in children without chronic inflammatory disease (p = 0.007. Children with SLE were also older (mean ± sd = 14.2 ± 2.5 years than the comparison group (11.0 ± 3.6 years; p

  19. 21 CFR 866.5785 - Anti-Saccharomyces cerevisiae (S. cerevisiae) antibody (ASCA) test systems. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Anti-Saccharomyces cerevisiae (S. cerevisiae... Immunological Test Systems § 866.5785 Anti-Saccharomyces cerevisiae (S. cerevisiae) antibody (ASCA) test systems. (a) Identification. The Anti-Saccharomyces cerevisiae (S. cerevisiae) antibody (ASCA) test system...

  20. Antibodies against G-protein coupled receptors: novel uses in screening and drug development. (United States)

    Gupta, Achla; Heimann, Andrea S; Gomes, Ivone; Devi, Lakshmi A


    Antibodies are components of the body's humoral immune system that are generated in response to foreign pathogens. Modern biomedical research has employed these very specific and efficient molecules designed by nature in the diagnosis of diseases, localization of gene products as well as in the rapid screening of targets for drug discovery and testing. In addition, the introduction of antibodies with fluorescent or enzymatic tags has significantly contributed to advances in imaging and microarray technology, which are revolutionizing disease research and the search for effective therapeutics. More recently antibodies have been used in the isolation of dimeric G protein-coupled receptor (GPCR) complexes. In this review, we discuss antibodies as powerful research tools for studying GPCRs, and their potential to be developed as drugs themselves.

  1. Development of an EGFRvIII specific recombinant antibody

    Directory of Open Access Journals (Sweden)

    Li Gordon


    Full Text Available Abstract Background EGF receptor variant III (EGFRvIII is the most common variant of the EGF receptor observed in human tumors. It results from the in frame deletion of exons 2-7 and the generation of a novel glycine residue at the junction of exons 1 and 8. This novel juxtaposition of amino acids within the extra-cellular domain of the EGF receptor creates a tumor specific and immunogenic epitope. EGFRvIII expression has been seen in many tumor types including glioblastoma multiforme (GBM, breast adenocarcinoma, non-small cell lung carcinoma, ovarian adenocarcinoma and prostate cancer, but has been rarely observed in normal tissue. Because this variant is tumor specific and highly immunogenic, it can be used for both a diagnostic marker as well as a target for immunotherapy. Unfortunately many of the monoclonal and polyclonal antibodies directed against EGFRvIII have cross reactivity to wild type EGFR or other non-specific proteins. Furthermore, a monoclonal antibody to EGFRvIII is not readily available to the scientific community. Results In this study, we have developed a recombinant antibody that is specific for EGFRvIII, has little cross reactivity for the wild type receptor, and which can be easily produced. We initially designed a recombinant antibody with two anti-EGFRvIII single chain Fv's linked together and a human IgG1 Fc component. To enhance the specificity of this antibody for EGFRvIII, we mutated tyrosine H59 of the CDRH2 domain and tyrosine H105 of the CDRH3 domain to phenylalanine for both the anti-EGFRvIII sequence inserts. This mutated recombinant antibody, called RAbDMvIII, specifically detects EGFRvIII expression in EGFRvIII expressing cell lines as well as in EGFRvIII expressing GBM primary tissue by western blot, immunohistochemistry (IHC and immunofluorescence (IF and FACS analysis. It does not recognize wild type EGFR in any of these assays. The affinity of this antibody for EGFRvIII peptide is 1.7 × 107 M-1 as

  2. Evaluation of the Canadian Rheumatology Association Choosing Wisely recommendation concerning anti-nuclear antibody (ANA) testing. (United States)

    Ferrari, Robert


    The objective of this study was to evaluate the Canadian Rheumatology Association Choosing Wisely recommendation concerning anti-nuclear antibody (ANA) testing. Patients with joint pain/stiffness/swelling were assessed to determine if ANA testing was indicated. An a priori threshold was set before ANA testing would be considered. Those who did not have ANA testing ordered were followed for 1 year to determine if any of them went on to have a diagnosis of systemic lupus erythematosus (SLE) or other connective tissue disease. A parallel study was conducted with a similar a priori threshold for the use of rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibody testing in the diagnosis of rheumatoid arthritis (RA), and again, patients were followed for 1 year. A total of 866 subjects were examined, 509 females (58.8 %) and 357 males (41.2 %). The mean age of the group was 47.5 ± 16.8 years. The mean duration of symptoms was 12.0 ± 5.6 weeks. Of the 866 subjects, 68 met an a priori threshold for ordering ANA, RF, and anti-CCP testing. Of these 68, there was a newly diagnosed case of SLE, 4 newly diagnosed cases of RA, and 3 cases of polymyalgia rheumatica. The remaining 798 subjects were followed for approximately 1 year and none developed evidence of SLE, RA, or other connective tissue disease. In the evaluation of non-specific musculoskeletal symptoms, setting an a priori threshold for ordering serology in keeping with the spirit of the Canadian Rheumatology Association Choosing Wisely recommendation for antibody testing results in a very low risk of missing a case of systemic lupus erythematosus or rheumatoid arthritis.

  3. Heterophilic antibodies interfering with radioimmunoassay. A false-positive pregnancy test

    Energy Technology Data Exchange (ETDEWEB)

    Vladutiu, A.O.; Sulewski, J.M.; Pudlak, K.A.; Stull, C.G.


    A young woman with amenorrhea had a consistently positive pregnancy test result (serum radioimmunoassay measurement of ..beta..-human chorionic gonadotropin hormone). No fetal or placental tissue was found after uterine curettage and exploratory laparotomy. The false-positive pregnancy test result was due to heterophilic antibovine and antigoat antibodies in the patient's serum. These antibodies interfered with radioimmunoassays using goat antibodies. This case shows that serum heterophilic antibodies can interfere with immunoassays and result in unnecessary diagnostic procedures and/or unnecessary treatment.

  4. Recent Developments in Antibody-Based Assays for the Detection of Bacterial Toxins

    Directory of Open Access Journals (Sweden)

    Kui Zhu


    Full Text Available Considering the urgent demand for rapid and accurate determination of bacterial toxins and the recent promising developments in nanotechnology and microfluidics, this review summarizes new achievements of the past five years. Firstly, bacterial toxins will be categorized according to their antibody binding properties into low and high molecular weight compounds. Secondly, the types of antibodies and new techniques for producing antibodies are discussed, including poly- and mono-clonal antibodies, single-chain variable fragments (scFv, as well as heavy-chain and recombinant antibodies. Thirdly, the use of different nanomaterials, such as gold nanoparticles (AuNPs, magnetic nanoparticles (MNPs, quantum dots (QDs and carbon nanomaterials (graphene and carbon nanotube, for labeling antibodies and toxins or for readout techniques will be summarized. Fourthly, microscale analysis or minimized devices, for example microfluidics or lab-on-a-chip (LOC, which have attracted increasing attention in combination with immunoassays for the robust detection or point-of-care testing (POCT, will be reviewed. Finally, some new materials and analytical strategies, which might be promising for analyzing toxins in the near future, will be shortly introduced.

  5. Recent developments in antibody-based assays for the detection of bacterial toxins. (United States)

    Zhu, Kui; Dietrich, Richard; Didier, Andrea; Doyscher, Dominik; Märtlbauer, Erwin


    Considering the urgent demand for rapid and accurate determination of bacterial toxins and the recent promising developments in nanotechnology and microfluidics, this review summarizes new achievements of the past five years. Firstly, bacterial toxins will be categorized according to their antibody binding properties into low and high molecular weight compounds. Secondly, the types of antibodies and new techniques for producing antibodies are discussed, including poly- and mono-clonal antibodies, single-chain variable fragments (scFv), as well as heavy-chain and recombinant antibodies. Thirdly, the use of different nanomaterials, such as gold nanoparticles (AuNPs), magnetic nanoparticles (MNPs), quantum dots (QDs) and carbon nanomaterials (graphene and carbon nanotube), for labeling antibodies and toxins or for readout techniques will be summarized. Fourthly, microscale analysis or minimized devices, for example microfluidics or lab-on-a-chip (LOC), which have attracted increasing attention in combination with immunoassays for the robust detection or point-of-care testing (POCT), will be reviewed. Finally, some new materials and analytical strategies, which might be promising for analyzing toxins in the near future, will be shortly introduced.

  6. Development of Antibody-Coated Magnetite Nanoparticles for Biomarker Immobilization

    Directory of Open Access Journals (Sweden)

    Christian Chapa Gonzalez


    Full Text Available Magnetic nanoparticles (MNPs have great potential in biomedical applications because of their magnetic response offers the possibility to direct them to specific areas and target biological entities. Magnetic separation of biomolecules is one of the most important applications of MNPs because their versatility in detecting cancer biomarkers. However, the effectiveness of this method depends on many factors, including the type of functionalization onto MNPs. Therefore, in this study, magnetite nanoparticles have been developed in order to separate the 5′-nucleotidase enzyme (5eNT. The 5eNT is used as a bio-indicator for diagnosing diseases such as hepatic ischaemia, liver tumor, and hepatotoxic drugs damage. Magnetic nanoparticles were covered in a core/shell type with silica, aminosilane, and a double shell of silica-aminosilane. A ScFv (fragment antibody and anti-CD73 antibody were attached to the coated nanoparticles in order to separate the enzyme. The magnetic separation of this enzyme with fragment antibody was found to be 28% higher than anti-CD73 antibody and the enzyme adsorption was improved with the double shell due to the increased length of the polymeric chain. Magnetite nanoparticles with a double shell (silica-aminosilane were also found to be more sensitive than magnetite with a single shell in the detection of biomarkers.

  7. Evaluation of screening tests for the detection of antistreptolysin O antibodies.


    Lue, Y. A.; Nicolas, C.; Kemawikasit, P.; Pierre, A.; McLean, T I; Simms, D H


    The accuracy of two screening tests, one utilizing serum and the other utilizing whole blood, was compared with the accuracy of the conventional macrotitration method for the detection of antistreptolysin O antibodies. Of the 569 specimens tested with the serum screening procedure and the macrotitration method, 235 and 282, respectively, were positive for antistreptolysin O antibodies. Comparative testing of 200 specimens with the peripheral blood screening test and the macrotitration method ...

  8. Development of a Sensitive and Specific Polyclonal Antibody for Serological Detection of Clavibacter michiganensis subsp. sepedonicus (United States)

    Przewodowska, Agnieszka


    The quarantine bacterium Clavibacter michiganensis subsp. sepedonicus (Cms) causes bacterial ring rot (BRR) in potato but is difficult to detect, hampering the diagnosis of this disease. ELISA immunoassays have not been widely used to detect Cms because commercially available anti-Cms antibodies detect mainly EPS-producing bacteria and can fail to detect strains that do not produce EPS. In the current study, we developed a new type of polyclonal antibody that specifically detects Clavibacter michiganensis subsp. sepedonicus bacteria irrespective of their EPS level. We first found that the presence of bacterial EPS precluded quantitative measurement of bacteria by currently available immunoenzymatic methods, but that washing Cms cells with acidic and basic buffers to remove EPS before analysis successfully standardized ELISA results. We used a mix of three strains of Cms with diverse EPS levels to generate antigen for production of antibodies recognizing Cms cells with and without an EPS layer (IgG-EPS and IgG-N-EPS, respectively). The resulting IgG-N-EPS recognized almost all Cms strains tested in this work regardless of their mucoidal level. The availability of this new antibody renders immunological diagnostics of Cms more sensitive and reliable, as our newly developed antibodies can be used in many type of immunoassays. This work represents an important step forward in efforts to diagnose and prevent the spread of BRR, and the methods and solutions developed in this work are covered by six Polish, one European and one US patents. PMID:28068400

  9. VNAR single-domain antibodies specific for BAFF inhibit B cell development by molecular mimicry. (United States)

    Häsler, Julien; Flajnik, Martin F; Williams, Gareth; Walsh, Frank S; Rutkowski, J Lynn


    B cell-activating factor (BAFF) plays a dominant role in the B cell homeostasis. However, excessive BAFF promotes the development of autoreactive B-cells and several antibodies have been developed to block its activity. Bispecific antibodies with added functionality represent the next wave of biologics that may be more effective in the treatment of complex autoimmune disease. The single variable domain from the immunoglobulin new antigen receptor (VNAR) is one of the smallest antibody recognition units that could be combined with monospecific antibodies to develop bispecific agents. We isolated a panel of BAFF-binding VNARs with low nM potency from a semi-synthetic phage display library and examined their functional activity. The anti-BAFF VNARs blocked the binding of BAFF to all three of its receptors (BR3, TACI and BCMA) and the presence of the conserved DXL receptor motif found in the CDR3 regions suggests molecular mimicry as the mechanism of antagonism. One clone was formatted as an Fc fusion for functional testing and it was found to inhibit both mouse and human BAFF with equal potency ex vivo in a splenocyte proliferation assay. In mice, subchronic administration reduced the number of immature and transitional intermediates B cells and mature B cell subsets. These results indicate that VNAR single domain antibodies function as selective B-cell inhibitors and offer an alternative molecular format for targeting B-cell disorders.

  10. Development and characterization of antibody reagents for detecting nanoparticles (United States)

    Ravichandran, Supriya; Sullivan, Mark A.; Callahan, Linda M.; Bentley, Karen L.; Delouise, Lisa A.


    The increasing use of nanoparticles (NPs) in technological applications and in commercial products has escalated environmental health and safety concerns. The detection of NPs in the environment and in biological systems is challenged by limitations associated with commonly used analytical techniques. In this paper we report on the development and characterization of NP binding antibodies, termed NProbes. Phage display methodology was used to discover antibodies that bind NPs dispersed in solution. We present a proof-of-concept for the generation of NProbes and their use for detecting quantum dots and titanium dioxide NPs in vitro and in an ex vivo human skin model. Continued development and refinement of NProbes to detect NPs that vary in composition, shape, size, and surface coating will comprise a powerful tool kit that can be used to advance nanotechnology research particularly in the nanotoxicology and nanotherapeutics fields.The increasing use of nanoparticles (NPs) in technological applications and in commercial products has escalated environmental health and safety concerns. The detection of NPs in the environment and in biological systems is challenged by limitations associated with commonly used analytical techniques. In this paper we report on the development and characterization of NP binding antibodies, termed NProbes. Phage display methodology was used to discover antibodies that bind NPs dispersed in solution. We present a proof-of-concept for the generation of NProbes and their use for detecting quantum dots and titanium dioxide NPs in vitro and in an ex vivo human skin model. Continued development and refinement of NProbes to detect NPs that vary in composition, shape, size, and surface coating will comprise a powerful tool kit that can be used to advance nanotechnology research particularly in the nanotoxicology and nanotherapeutics fields. Electronic supplementary information (ESI) available: Figures and detailed methods of various techniques

  11. Evaluation Of Algorithms Of Anti- HIV Antibody Tests

    Directory of Open Access Journals (Sweden)

    Paranjape R.S


    Full Text Available Research question: Can alternate algorithms be used in place of conventional algorithm for epidemiological studies of HIV infection with less expenses? Objective: To compare the results of HIV sero- prevalence as determined by test algorithms combining three kits with conventional test algorithm. Study design: Cross â€" sectional. Participants: 282 truck drivers. Statistical analysis: Sensitivity and specificity analysis and predictive values. Results: Three different algorithms that do not include Western Blot (WB were compared with the conventional algorithm, in a truck driver population with 5.6% prevalence of HIV â€"I infection. Algorithms with one EIA (Genetic Systems or Biotest and a rapid test (immunocomb or with two EIAs showed 100% positive predictive value in relation to the conventional algorithm. Using an algorithm with EIA as screening test and a rapid test as a confirmatory test was 50 to 70% less expensive than the conventional algorithm per positive scrum sample. These algorithms obviate the interpretation of indeterminate results and also give differential diagnosis of HIV-2 infection. Alternate algorithms are ideally suited for community based control programme in developing countries. Application of these algorithms in population with low prevalence should also be studied in order to evaluate universal applicability.

  12. Comparison of enzyme-linked immunosorbent assays and virus neutralization test for detection of antibodies to avian pneumovirus. (United States)

    Alkahalaf, A N; Halvorson, D A; Saif, Y M


    Two different whole-virus enzyme-linked immunosorbent assays (ELISAs), developed in Ohio (OH) with APV/Minnesota/turkey/2a/97 and in Minnesota (MN) with APV/Colorado/turkey/97, and the virus neutralization (VN) test were used to test 270 turkey serum samples from 27 Minnesota turkey flocks for avian pneumovirus (APV) antibodies. In addition, 77 turkey serum samples and 128 ostrich serum samples from Ohio were tested. None of the turkey samples from Ohio had antibodies to APV by the VN test and OH ELISA. The ostrich samples were only tested with the VN test and were all negative for antibodies to APV. For the Minnesota serum samples, 107, 115, and 120 were positive by the VN test, the OH ELISA, and the MN ELISA, respectively. The Kappa values of 0.938 and 0.825 showed excellent agreement between the VN test and the OH ELISA and the MN ELISA, respectively, for detection of antibodies to the APV. The OH ELISA and MN ELISA had sensitivities of 1.0 and 0.953, specificities of 0.950 and 0.889, and accuracies of 0.970 and 0.914, respectively. Our results indicate that the 3 methods are sensitive and specific for diagnosis of the APV infection.

  13. A Comparative Study of Detection of Bordetella avium Antibodies in Turkeys by ELISA, SPAT, and AGID Test


    TÜRKYILMAZ, Süheyla; TÜRKYILMAZ, Kenan; KAYA, Osman


    The aims of this study were to develop a serum plate agglutination test (SPAT) antigen and agar gel immunodiffusion (AGID) test antigen for the serological detection of turkeys that have been exposed to Bordetella avium; to compare the sensitivity of commercial enzyme-linked immunosorbent assay (ELISA) with SPAT, and AGID test, and to survey B. avium antibodies in turkey flocks in Aydın, Turkey. For these purposes, serum samples collected from 300 turkeys were examined by ELISA, SPAT, and AGI...

  14. 21 CFR 866.5120 - Antismooth muscle antibody immunological test system. (United States)


    ... autoimmune connective tissue diseases (diseases resulting from antibodies produced against the body's own... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Antismooth muscle antibody immunological test system. 866.5120 Section 866.5120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH...

  15. The generation of monoclonal antibodies and their use in rapid diagnostic tests (United States)

    Antibodies are the most important component of an immunoassay. In these proceedings we outline novel methods used to generate and select monoclonal antibodies that meet performance criteria for use in rapid lateral flow and microfluidic immunoassay tests for the detection of agricultural pathogens ...

  16. Effect of skin test on serum antibody responses to Mycobacterium bovis infection in cattle (United States)

    Recently, several serologic tests designed to detect immunodominant antibodies to M. bovis antigens (e.g., MPB83, MPB70, ESAT-6, and CFP10) have emerged for potential use with samples from cattle. Of these, a commercial ELISA to MPB83/MPB70 (M. bovis antibody ELISA) has gained approval for use in ca...

  17. Development of recombinant antigen array for simultaneous detection of viral antibodies.

    Directory of Open Access Journals (Sweden)

    Yi Liu

    Full Text Available Protein microarrays have been developed to study antibody reactivity against a large number of antigens, demonstrating extensive perspective for clinical application. We developed a viral antigen array by spotting four recombinant antigens and synthetic peptide, including glycoprotein G of herpes simplex virus (HSV type 1 and 2, phosphoprotein 150 of cytomegalovirus (CMV, Rubella virus (RV core plus glycoprotein E1 and E2 as well as a E1 peptide with the optimal concentrations on activated glass slides to simultaneously detect IgG and IgM against HSV1, HSV2, CMV and RV in clinical specimens of sera and cerebrospinal fluids (CSFs. The positive reference sera were initially used to measure the sensitivity and specificity of the array with the optimal conditions. Then clinical specimens of 144 sera and 93 CSFs were tested for IgG and IgM antibodies directed against HSV1, HSV2, CMV and RV by the antigen array. Specificity of the antigen array for viral antibodies detection was satisfying compared to commercial ELISA kits but sensitivity of the array varied relying on quality and antigenic epitopes of the spotting antigens. In short, the recombinant antigen array has potential to simultaneous detect multiple viral antibodies using minute amount (3 µl of samples, which holds the particularly advantage to detect viral antibodies in clinical CSFs being suspicious of neonatal meningitis and encephalitis.

  18. Discontinuation of Smoking Increases the Risk for Developing Thyroid Peroxidase Antibodies and/or Thyroglobulin Antibodies: A Prospective Study

    NARCIS (Netherlands)

    G. Effraimidis; J.G.P. Tijssen; W.M. Wiersinga


    Context: Autoimmune thyroid disease develops in genetic susceptible subjects, provoked by environmental factors. Little is known of the environment in the early stages of autoimmunity. Objective: We evaluated environmental factors contributing to de novo occurrence of thyroid antibodies. Design: We

  19. Correlates of participation in AIDS education and HIV antibody testing by methadone patients. (United States)

    Magura, S; Grossman, J I; Lipton, D S; Amann, K R; Koger, J; Gehan, K


    The authors examined the factors associated with methadone patients' decisions about participating in a clinic-based AIDS prevention protocol. Despite the offer of incentives, only 27 percent attended AIDS education and only 12 percent obtained voluntary HIV antibody (ab) testing. However, AIDS education was attended by proportionately more of those who were at highest risk for AIDS because of current intravenous drug use. The availability of HIV-ab testing neither encouraged nor discouraged participation in AIDS education. Patients who were relatively more likely to choose HIV-ab testing were older, had been or were married, had plans to have children, believed the test to be useful, and believed that their counselors support their decision to be tested. Those who declined to be tested were reluctant to confront the emotional aspects of their risk status, were concerned about possible breaches of confidentiality, and doubted the value of testing. The implications of the findings for implementing AIDS prevention measures in methadone programs are discussed. Programs need either to require attendance at AIDS education or give patients an incentive to attend. HIV-ab testing should be available but should remain voluntary. A stronger medical rationale for testing is developing and may increase future participation. Methadone programs must continue to engage patients actively in AIDS risk reduction efforts.

  20. Trends in Upstream and Downstream Process Development for Antibody Manufacturing

    Directory of Open Access Journals (Sweden)

    Petra Gronemeyer


    Full Text Available A steady increase of product titers and the corresponding change in impurity composition represent a challenge for development and optimization of antibody production processes. Additionally, increasing demands on product quality result in higher complexity of processes and analytics, thereby increasing the costs for product work-up. Concentration and composition of impurities are critical for efficient process development. These impurities can show significant variations, which primarily depend on culture conditions. They have a major impact on the work-up strategy and costs. The resulting “bottleneck” in downstream processing requires new optimization, technology and development approaches. These include the optimization and adaptation of existing unit operations respective to the new separation task, the assessment of alternative separation technologies and the search for new methods in process development. This review presents an overview of existing methods for process optimization and integration and indicates new approaches for future developments.

  1. Development of a blocking ELISA for detection of antibodies against avian hepatitis E virus. (United States)

    Liu, Baoyuan; Zhao, Qin; Sun, Yani; Wang, Xinjie; Zhao, Jinan; Du, Taofeng; Wang, Chengbao; Xiao, Shuqi; Mu, Yang; Zhang, Gaiping; Luo, Jianxun; Hsu, Walter H; Zhou, En-Min


    A blocking enzyme-linked immunosorbent assay (bELISA) was developed for the detection of immunoglobulin G antibodies against avian hepatitis E virus (HEV). In the bELISA, the coating antigen was a truncated protein containing C-terminal 268-amino acid region of ORF2 from an avian HEV strain isolated in China (CaHEV) and blocking antibody was a monoclonal antibody (mAb) 1H5 recognizing the epitope within amino acids 384-414 in the C-terminal 268-amino acid region. The concentration of blocking mAb 1H5 was determined as that yielded an OD450nm value of 1.0 for binding to the coating antigen and the antigen concentration and serum dilution were optimized using a checkerboard titration. A cut-off value of 20.7% at the mean percent inhibition plus 3 standard deviations was determined by testing 265 negative sera. The bELISA had a sensitivity of 98.3% by testing 116 positive sera from chickens infected experimentally with CaHEV and had no cross-reaction with other anti-avian virus antibodies. The compliance rates of the bELISA with indirect ELISA and Western blot were 83.7% and 93.3%, respectively, by testing 300 field chicken sera. These results suggested that the bELISA developed in this study can be used for detection of antibodies against avian HEV and showed high reproducibility compared with indirect ELISA and Western blot methods.

  2. DARPA Antibody Technology Program Standardized Test Bed for Antibody Characterization: Characterization of an MS2 sdAb Produced by U.S. Naval Research Laboratory (United States)


    Biosurveillance (JPMO BSV), Critical Reagents Program instituted a quality program for the standardization of test methods to support more...operational and performance metrics for future detection and diagnostic platforms. 15. SUBJECT TERMS Antibody Biosurveillance Antibody Technology... Biosurveillance (JPMO BSV), Critical Reagents Program (CRP) instituted a quality program for the standardization of test methods to more fully characterize

  3. Solderability test development. Final report. [Meniscograph tests

    Energy Technology Data Exchange (ETDEWEB)

    Jarboe, D.M.


    Operating procedures and data reduction techniques applicable to the Meniscograph (General Electric Company, Limited) were developed. Using force-time traces from tests involving various sample materials and configurations, flux types, and test temperatures, the wetting rate and contact angle were obtained through statistical treatment of the data. This information provides a means of directly correlating solderability with the physical phenomenon of wetting.

  4. Ready Access to Proquinazid Haptens via Cross-Coupling Chemistry for Antibody Generation and Immunoassay Development (United States)

    Esteve-Turrillas, Francesc A.; Mercader, Josep V.; Parra, Javier; Agulló, Consuelo; Abad-Somovilla, Antonio; Abad-Fuentes, Antonio


    Bioconjugate preparation is a fundamental step for antibody generation and immunoassay development to small chemical compounds. For analytical targets holding in their structure an aryl halogen atom, cross-coupling reactions may be a simple and efficient way to obtain functionalized derivatives; thus offering great potential to elicit robust and selective immune responses after being coupled to immunogenic carrier proteins. However, substitution of the halogen atom by an aliphatic chain might eventually compromise the affinity and specificity of the resulting antibodies. In order to address this issue, proquinazid, a new-generation fungicide with outstanding performance, was chosen as model analyte. Two functionalized derivatives differing in spacer arm rigidity were synthesized by Sonogashira cross-coupling chemistry. These haptens were covalently coupled to bovine serum albumin and the resulting immunoconjugates were employed for rabbit vaccination. Antibodies were tested for proquinazid recognition by direct and indirect competitive immunoassay, and IC50 values in the low nanomolar range were found, thus demonstrating the suitability of this straightforward synthetic strategy for the generation of immunoreagents to compounds bearing an aryl halide. Following antibody characterization, competitive immunoassays were developed and employed to determine proquinazid residues in grape musts, and their analytical performance was satisfactorily validated by comparison with GC–MS. Besides having described the development of the first immunochemical method for proquinazid analysis, an efficient functionalization approach for analytes comprising aryl halides is reported. PMID:26214507

  5. Ready Access to Proquinazid Haptens via Cross-Coupling Chemistry for Antibody Generation and Immunoassay Development.

    Directory of Open Access Journals (Sweden)

    Francesc A Esteve-Turrillas

    Full Text Available Bioconjugate preparation is a fundamental step for antibody generation and immunoassay development to small chemical compounds. For analytical targets holding in their structure an aryl halogen atom, cross-coupling reactions may be a simple and efficient way to obtain functionalized derivatives; thus offering great potential to elicit robust and selective immune responses after being coupled to immunogenic carrier proteins. However, substitution of the halogen atom by an aliphatic chain might eventually compromise the affinity and specificity of the resulting antibodies. In order to address this issue, proquinazid, a new-generation fungicide with outstanding performance, was chosen as model analyte. Two functionalized derivatives differing in spacer arm rigidity were synthesized by Sonogashira cross-coupling chemistry. These haptens were covalently coupled to bovine serum albumin and the resulting immunoconjugates were employed for rabbit vaccination. Antibodies were tested for proquinazid recognition by direct and indirect competitive immunoassay, and IC50 values in the low nanomolar range were found, thus demonstrating the suitability of this straightforward synthetic strategy for the generation of immunoreagents to compounds bearing an aryl halide. Following antibody characterization, competitive immunoassays were developed and employed to determine proquinazid residues in grape musts, and their analytical performance was satisfactorily validated by comparison with GC-MS. Besides having described the development of the first immunochemical method for proquinazid analysis, an efficient functionalization approach for analytes comprising aryl halides is reported.

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

    Directory of Open Access Journals (Sweden)

    Phelps Amanda L


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

  7. Standardization and demonstration of antibody-coated Candida in urine by direct immunofluorescence test. (United States)

    Talwar, P; Pal, S R; Kaur, P; Kaiwar, R; Jayashree, T; Rao, M S; Vaidyanathan, S; Taiwar, P


    Acetone, carbontetrachloride, ethyl alcohol, mixture of ethyl alcohol and acetone, and heat were assessed for fixative property for direct immunofluorescent (IF) staining of antibody-coated Candida cells. The results indicated that ethyl alcohol was the most suitable fixative for the test. Antisera containing 16 units of Candida albicans type A agglutinin were found essential to get optimal detectable fluorescence of antibody-coated yeast cells. IF test showed cross reactivity between the yeasts of C. albicans and C. tropicalis. However, there was no cross reactivity with the conidia of A. flavus. The direct IF test could demonstrate antibody-coated yeast cells and pseudomycelia in deposits of urine in the direct smear. It correlated well with microscopy and culture studies. At times, it could demonstrate the antibody-coated yeasts earlier than routine significant culture. It could also differentiate the significant from non-significant fungal isolates from urine.

  8. Phage display-derived human antibodies in clinical development and therapy. (United States)

    Frenzel, André; Schirrmann, Thomas; Hust, Michael


    Over the last 3 decades, monoclonal antibodies have become the most important class of therapeutic biologicals on the market. Development of therapeutic antibodies was accelerated by recombinant DNA technologies, which allowed the humanization of murine monoclonal antibodies to make them more similar to those of the human body and suitable for a broad range of chronic diseases like cancer and autoimmune diseases. In the early 1990s in vitro antibody selection technologies were developed that enabled the discovery of "fully" human antibodies with potentially superior clinical efficacy and lowest immunogenicity. Antibody phage display is the first and most widely used of the in vitro selection technologies. It has proven to be a robust, versatile platform technology for the discovery of human antibodies and a powerful engineering tool to improve antibody properties. As of the beginning of 2016, 6 human antibodies discovered or further developed by phage display were approved for therapy. In 2002, adalimumab (Humira®) became the first phage display-derived antibody granted a marketing approval. Humira® was also the first approved human antibody, and it is currently the best-selling antibody drug on the market. Numerous phage display-derived antibodies are currently under advanced clinical investigation, and, despite the availability of other technologies such as human antibody-producing transgenic mice, phage display has not lost its importance for the discovery and engineering of therapeutic antibodies. Here, we provide a comprehensive overview about phage display-derived antibodies that are approved for therapy or in clinical development. A selection of these antibodies is described in more detail to demonstrate different aspects of the phage display technology and its development over the last 25 years.

  9. Radiometric cytolysis inhibition assay, a new rapid test for neutralizing antibodies to intact and trypsin-cleaved poliovirus

    Energy Technology Data Exchange (ETDEWEB)

    Hovi, T.; Roivainen, M.


    We have developed a new rapid test, the radiometric cytolysis inhibition assay (RACINA), for the determination of neutralizing poliovirus antibodies. HeLa cells prelabeled with /sup 51/Cr, (/sup 3/H)leucine, or, preferentially, with (/sup 3/H)uridine are used as sensitive quantitative indicators of residual infectious virus. Both suspensions and monolayer cultures of the indicator cells can be used. Neutralization of a fraction of a high-titer virus preparation can be scored after the first replication cycle at 8 to 10 h. By lowering the incubation temperature to 30/degree/C, the completion of the cytolysis due to the first replication cycle of poliovirus was delayed beyond 21 h. This makes it possible to use the RACINA, unlike the standard microneutralization assay, for measuring antibodies to trypsin-cleaved polioviruses. The RACINA was found to be as sensitive as and more reproducible than the standard microneutralization assay in the measurement of neutralizing poliovirus antibodies. The RACINA is a rapid and reliable test for neutralizing antibodies and in principle it may be applicable for quantitation of neutralizing antibodies to other cytolytic agents as well.

  10. Evaluation of toxin neutralisation in test systems for diphtheria antibody assessment. (United States)

    Vandenberg, J; van der Gun, J W; Hendriksen, C F


    Over the past years, various authors have reported that the amount of toxin used in toxin neutralisation (TN) assays for diphtheria appears to influence the resulting relative antibody titre. Antibody affinity is thought to be an influencing factor. To confirm this observation and study the underlying mechanism of toxin neutralisation, a panel of sera was generated, differing in species of origin (mouse, guinea pig, and rabbit) and in affinity by using different immunisation schedules. The panel was then tested in relevant TN test systems for diphtheria antibody titration, namely the VERO cell test, the Toxin Binding Inhibition (ToBI) assay and the in vivo skin test in guinea pigs. A hyperimmune equine reference serum was used as the standard. Antibody affinity was measured in two different affinity ELISAs, the ammonium thiocyanate elution ELISA and the diethylamine inhibition ELISA. The VERO cell test clearly demonstrates the phenomenon; the higher the toxin dose used in the assay, the higher the resulting relative potency. The difference in relative antibody titre decreases as antibody affinity increases. This is especially evident when an equine hyperimmune reference serum is used as the standard. When a species homologous reference is used, the phenomenon is less distinct. The ToBI test, however, does not show the phenomenon. This discrepancy between these two test systems is being further investigated, and comparison will be made with the in vivo TN test. The findings confirm and support earlier observations. It is still unclear exactly which mechanisms are involved in the toxin neutralisation process. Antibody subclasses and class switching could play a role and will be further studied.

  11. Selecting an acceptable and safe antibody detection test can present a dilemma. (United States)

    Combs, M R; Bredehoeft, S J


    The Transfusion Service at Duke University Hospital has changed antibody detection methods from the use of albumin in indirect antiglobulin tests to low-ionic-strength solution (LISS), and from LISS to polyethylene glycol (PEG) in an effort to enhance the rapid detection of clinically significant antibodies. In 1996, staffing issues required the consideration of automation. Although previous studies indicated that the gel test was not as sensitive as PEG for detection of clinically significant antibodies, we chose to implement the gel test to be used with the Tecan MegaFlex-ID. We performed a retrospective analysis of identified antibodies and transfusion reactions to compare the outcomes of one year's experience with gel and PEG. We found comparable detection of potentially clinically significant antibodies by both methods and significantly fewer unwanted or clinically insignificant antibodies detected with the use of gel. Fewer delayed serologic transfusion reactions and no transfusion-associated hemolytic events occurred in the year that gel was used. Although we initially found the selection of the gel test to be a dilemma, our ultimate decision appears to have successfully protected patient safety and balanced sensitivity with specificity.

  12. Bulk tank milk ELISA for detection of antibodies to Mycobacterium avium subsp paratuberculosis: Correlation between repeated tests and within-herd antibody-prevalence

    DEFF Research Database (Denmark)

    Nielsen, Søren Saxmose; Toft, Nils


    Detection of bulk tank milk (BTM) antibodies using ELISA (BTM-ELISA) may constitute an inexpensive test for surveillance of Mycobacterium avium subsp. paratuberculosis (MAP) infection in dairy cattle herds provided that the test is accurate and consistent. The objectives of this study were...... to determine: (a) the correlation between repeated BTM reactions; and (b) the association between the BTM antibody ELISA-level and the within-herd prevalence of antibody-positive cows. Eight BTM samples per herd and approximately four milk samples per lactating cow per herd were collected from each of 108...... Danish Holstein herds over a period of one year. All samples were tested using a commercial indirect ELISA for detection of MAP specific antibodies. The individual cow's results were dichotomised and used to estimate the within-herd antibody prevalence at each test-date. These prevalences were...

  13. Hepatitis B core antibody testing in Indian blood donors: A double-edged sword!

    Directory of Open Access Journals (Sweden)

    R N Makroo


    Full Text Available Background: Until lately, anti-HBc antibodies were considered an effective marker for occult Hepatitis B virus (HBV infection and have served their role in improving blood safety. But, with the development of advanced tests for HBV DNA detection, the role of anti-HBc in this regard stands uncertain. Materials and Methods: Anti-HBc and HBsAg ELISA and ID-NAT tests were run in parallel on donor blood samples between April 1, 2006 and December 31, 2010 at the Department of Transfusion Medicine, Indraprastha Apollo Hospitals, New Delhi. A positive ID-NAT was followed by Discriminatory NAT assay. Results: A total of 94 247 samples were tested with a total core positivity rate of 10.22%. We identified nearly 9.17% of donors who were reactive for anti-HBc and negative for HBsAg and HBV DNA. These are the donors who are potentially non-infectious and may be returned to the donor pool. Conclusion: Although anti HBc testing has a definite role in improving blood safety, centers that have incorporated NAT testing may not derive any additional benefit by performing anti-HBc testing, especially in resource-limited countries like ours.

  14. Development and evaluation of a competitive ELISA using a monoclonal antibody for antibody detection after goose parvovirus virus-like particles (VLPs) and vaccine immunization in goose sera. (United States)

    Wang, Qian; Ju, Huanyu; Li, Yanwei; Jing, Zhiqiang; Guo, Lu; Zhao, Yu; Ma, Bo; Gao, Mingchun; Zhang, Wenlong; Wang, Junwei


    An assay protocol based on a monoclonal antibody-based competitive enzyme-linked immunosorbent assay (MAb-based C-ELISA) for detecting antibodies against goose parvovirus (GPV) and its virus-like particles (VLPs) is described. The assay was developed using baculovirus-expressed recombinant VP2 virus-like particles (rVP2-VLPs) as antigens and a monoclonal antibody against GPV as the competitive antibody. Of the four anti-GPV MAbs that were screened, MAb 1G3 was selected as it was blocked by the GPV positive serum. Based on the distribution of percent inhibition (PI) of the known negative sera (n=225), a cut-off value was set at 36% inhibition. Using this cut-off value, the sensitivity of the assay was 93.3% and the specificity was 95.8%, as compared with the gold standard (virus neutralization assay). The rVP2-VLPs did not react with anti-sera to other goose pathogens, indicating that it is specific for the recognization of goose parvovirus antibodies. The assay was then validated with serum samples from goslings vaccinated with several VLPs (rVP1-VLPs, rVP2-VLPs, rVP3-VLPs, and rCGV-VLPs) and other vaccines (inactivated and attenuated). The C-ELISA described in this study is a sensitive and specific diagnostic test and should have wide applications for the sero-diagnosis and immunologic surveillance of GPV.

  15. Bispecific Antibodies as a Development Platform for New Concepts and Treatment Strategies

    Directory of Open Access Journals (Sweden)

    Fa Yang


    Full Text Available With the development of molecular cloning technology and the deep understanding of antibody engineering, there are diverse bispecific antibody formats from which to choose to pursue the optimal biological activity and clinical purpose. The single-chain-based bispecific antibodies usually bridge tumor cells with immune cells and form an immunological synapse because of their relatively small size. Bispecific antibodies in the IgG format include asymmetric bispecific antibodies and homodimerized bispecific antibodies, all of which have an extended blood half-life and their own crystalline fragment (Fc-mediated functions. Besides retargeting effector cells to the site of cancer, new applications were established for bispecific antibodies. Bispecific antibodies that can simultaneously bind to cell surface antigens and payloads are a very ideal delivery system for therapeutic use. Bispecific antibodies that can inhibit two correlated signaling molecules at the same time can be developed to overcome inherent or acquired resistance and to be more efficient angiogenesis inhibitors. Bispecific antibodies can also be used to treat hemophilia A by mimicking the function of factor VIII. Bispecific antibodies also have broad application prospects in bone disorders and infections and diseases of the central nervous system. The latest developments of the formats and application of bispecific antibodies will be reviewed. Furthermore, the challenges and perspectives are summarized in this review.


    Directory of Open Access Journals (Sweden)

    Goknur TERZI


    Full Text Available In this study Brucella antibodies were investigated with agglutination test (Whey-AT and Milk Ring Test (MRT in a total of 100 milk samples as 50 of cow milk and 50 of goat milk collected from center and villages of Samsun. According to MRT Brucella antibodies was positive at 10 samples (20 % of cow milk and 6 samples (12 % of goat milk. In cow milk, 4 (8 % positive, 3 (6 % suspicious and 43 (86 % negative samples; in goat milk 3 (6 % positive, 2 (4 % suspicious and 45 (90 % negative samples were determined according to antibodies titre of serum agglutination test (Whey-AT. [TAF Prev Med Bull 2006; 5(3.000: 196-203

  17. Rabies direct fluorescent antibody test does not inactivate rabies or eastern equine encephalitis viruses. (United States)

    Jarvis, Jodie A; Franke, Mary A; Davis, April D


    An examination using the routine rabies direct fluorescent antibody test was performed on rabies or Eastern equine encephalitis positive mammalian brain tissue to assess inactivation of the virus. Neither virus was inactivated with acetone fixation nor the routine test, thus laboratory employees should treat all samples as rabies and when appropriate Eastern equine encephalitis positive throughout the whole procedure.

  18. Development and application of an indirect ELISA for detection of antibodies against avian hepatitis E virus. (United States)

    Zhao, Qin; Sun, Yani; Zhao, Jinan; Hu, Shoubin; Zhao, Feifei; Chen, Fuyong; Clavijo, Alfonso; Zhou, En-Min; Xiao, Yihong


    An indirect enzyme-linked immunosorbent assay (iELISA) that could detect immunoglobulin G antibodies against avian hepatitis E virus (HEV) was developed. This assay employs a truncated C-terminal 268-amino acid recombinant ORF2 protein from an avian HEV genotype 3 strain isolated in China (CaHEV) as the coating antigen. The antigen concentration and serum dilution were optimized using a checkerboard titration. A cut-off value of 0.368 at OD(450nm) was determined by testing 120 positive and 200 negative chicken sera for avian HEV antibodies using the two-graph receiver operating characteristic (TG-ROC) analysis. This iELISA has a sensitivity of 96.1% and a specificity of 95.8%. The overall agreement between the iELISA and a corresponding Western blot was 97%. The iELISA was used to evaluate the seroprevalence of avian HEV in poultry farms in the Shandong province. The avian HEV seropositive rate of 35.9% was determined by testing 1871 serum samples that were collected from 10 chicken flocks ranged from 10 to 60 weeks of age. The iELISA that was developed in this study can be used for detection of immunoglobulin G antibodies against avian HEV.

  19. The clinical significance comparison of a latex agglutination based syphilis screening test at low antibody titer. (United States)

    Wang, Hua-Cheng; Chen, Cha; Wang, Li-Na; Long, Yi-Fei; Zhang, Wei-Zheng; Li, You-Qiang; Xiao, Qian; Yuan, Hui


    The rapid increase of syphilis underscores a tremendous need to carefully evaluate many new serological tests for syphilis and choose efficient and economical strategies for syphilis screening, especially in the case of primary infection with low antibody titer. Between 2011 and 2012, 73 patients' sera samples were included in this retrospective study. They were either TRUST or TPPA reactive, either LA (latex agglutination) based auto3 TP or CLIA (chemiluminescence assay) based Architect Syphilis TP assay reactive. The contradictory weak response samples were further examined by FTA-Abs method. TPPA could not give reactive results in samples with antibody concentration less than 10 mIU. Auto3 TP reagent shows good linearity at low antibody titers and was more sensitive than TPPA, while the former does not show significant superiority compared to the Architect Syphilis TP assay at low antibody titer, except that it is suitable for adaptation on diverse automated chemistry analyzers.

  20. Accuracy of diagnostic antibody tests for coeliac disease in children

    DEFF Research Database (Denmark)

    Giersiepen, Klaus; Lelgemann, Monika; Stuhldreher, Nina;


    The aim of this study was to summarise the evidence from 2004 to September 2009 on the performance of laboratory-based serological and point of care (POC) tests for diagnosing coeliac disease (CD) in children using histology as reference standard.......The aim of this study was to summarise the evidence from 2004 to September 2009 on the performance of laboratory-based serological and point of care (POC) tests for diagnosing coeliac disease (CD) in children using histology as reference standard....



    Goknur TERZI


    In this study Brucella antibodies were investigated with agglutination test (Whey-AT) and Milk Ring Test (MRT) in a total of 100 milk samples as 50 of cow milk and 50 of goat milk collected from center and villages of Samsun. According to MRT Brucella antibodies was positive at 10 samples (20 %) of cow milk and 6 samples (12 %) of goat milk. In cow milk, 4 (8 %) positive, 3 (6 %) suspicious and 43 (86 %) negative samples; in goat milk 3 (6 %) positive, 2 (4 %) suspicious and 45 (90 %) negativ...


    Institute of Scientific and Technical Information of China (English)

    张永安; 聂品


    Serum immunoglobulin from the mandarin fish, or the so-called Chinese perch, S iniperca chuatsi (Basilewsky), was successfully purified using affinity chroma togr aphy. Heavy and light chains were detected on electrophoresis gel, with molecula r weights being estimated at 72 and 29 kDa, respectively. The tetrameric IgM of S. chuatsi was calculated to be 808 kDa. The rabbit polyclonal antisera against the purifed immunoglobulin were developed and tested by Western blot analysis. The antisera reacted strongly with the heavy chains of S. chuat si immunoglobulin. Humoral immune responses of the mandarin fish can then be examined using the developed polyclonal antibody.

  3. Serum immunoglobulin of the mandarin fish, Siniperca chuatsi with development of polyclonal antibody (United States)

    Zhang, Yong-An; Nie, Pin


    Serum immunoglobulin from the mandarin fish, or the so-called Chinese perch, Siniperca chuatsi (Basilewsky), was successfully purified using affinity chromatography. Heavy and light chains were detected on electrophoresis gel, with molecular weights being estimated at 72 and 29 kDa, respectively. The tetrameric IgM of S. chuatsi was calculated to be 808 kDa. The rabbit polyclonal antisera against the purifed immunoglobulin were developed and tested by Western blot analysis. The antisera reacted strongly with the heavy chains of S. chuatsi immunoglobulin. Humoral immune responses of the mandarin fish can then be examined using the developed polyclonal antibody.

  4. Challenges in Antibody Development against Tn and Sialyl-Tn Antigens (United States)

    Loureiro, Liliana R.; Carrascal, Mylène A.; Barbas, Ana; Ramalho, José S.; Novo, Carlos; Delannoy, Philippe; Videira, Paula A.


    The carbohydrate antigens Tn and sialyl-Tn (STn) are expressed in most carcinomas and usually absent in healthy tissues. These antigens have been correlated with cancer progression and poor prognosis, and associated with immunosuppressive microenvironment. Presently they are used in clinical trials as therapeutic vaccination, but with limited success due to their low immunogenicity. Alternatively, anti-Tn and/or STn antibodies may be used to harness the immune system against tumor cells. Whilst the development of antibodies against these antigens had a boost two decades ago for diagnostic use, so far no such antibody entered into clinical trials. Possible limitations are the low specificity and efficiency of existing antibodies and that novel antibodies are still necessary. The vast array of methodologies available today will allow rapid antibody development and novel formats. Following the advent of hybridoma technology, the immortalization of human B cells became a methodology to obtain human monoclonal antibodies with better specificity. Advances in molecular biology including phage display technology for high throughput screening, transgenic mice and more recently molecularly engineered antibodies enhanced the field of antibody production. The development of novel antibodies against Tn and STn taking advantage of innovative technologies and engineering techniques may result in innovative therapeutic antibodies for cancer treatment. PMID:26270678

  5. Development of Biodegradable Nanocarriers Loaded with a Monoclonal Antibody

    Directory of Open Access Journals (Sweden)

    Andrew Gdowski


    Full Text Available Treatments utilizing monoclonal antibody therapeutics against intracellular protein-protein interactions in cancer cells have been hampered by several factors, including poor intracellular uptake and rapid lysosomal degradation. Our current work examines the feasibility of encapsulating monoclonal antibodies within poly(lactic-co-glycolic acid (PLGA nanoparticles using a water/oil/water double emulsion solvent evaporation technique. This method can be used to prepare protective polymeric nanoparticles for transporting functional antibodies to the cytoplasmic compartment of cancer cells. Nanoparticles were formulated and then characterized using a number of physical and biological parameters. The average nanoparticle size ranged from 221 to 252 nm with a low polydispersity index. Encapsulation efficiency of 16%–22% and antibody loading of 0.3%–1.12% were observed. The antibody molecules were released from the nanoparticles in a sustained manner and upon release maintained functionality. Our studies achieved successful formulation of antibody loaded polymeric nanoparticles, thus indicating that a PLGA-based antibody nanoformulation is a promising intracellular delivery vehicle for a large number of new intracellular antibody targets in cancer cells.

  6. Terasaki-ELISA for murine IgE-antibodies.I.Quality of the detecting antibody: production and specificity testing of antisera specific for IgE

    NARCIS (Netherlands)

    Savelkoul, H.F.J.; Soeting, P.W.C.; Radl, J.; Linde-Preesman, van der A.A.


    In order to develop an ELISA for the quantitative determination of murine IgE, antisera specific for murine IgE were prepared in the goat and rabbit. As immunogen, monoclonal IgE antibody mixtures of several allotypically different hybridomas were used. Before use, these antibodies were purified emp

  7. The Statistical Precision of Medical Screening Procedures: Application to Polygraph and AIDS Antibodies Test Data


    Gastwirth, Joseph L.


    The increased use of screening tests for drug use or antibodies to the HTLV-III (AIDS) virus, as well as pre-employment polygraph testing, has raised concerns about the reliability of the results of these procedures. This paper reviews the mathematical model underlying the analysis of data from screening tests. In addition to the known formulas for the proportion of positive (negative) classifications that are correct, we provide a large sample approximation to their standard errors. The resu...

  8. Development and Evaluation of Monoclonal Antibodies for Paxilline

    Directory of Open Access Journals (Sweden)

    Chris M. Maragos


    Full Text Available Paxilline (PAX is a tremorgenic mycotoxin that has been found in perennial ryegrass infected with Acremonium lolii. To facilitate screening for this toxin, four murine monoclonal antibodies (mAbs were developed. In competitive indirect enzyme-linked immunosorbent assays (CI-ELISAs the concentrations of PAX required to inhibit signal development by 50% (IC50s ranged from 1.2 to 2.5 ng/mL. One mAb (2-9 was applied to the detection of PAX in maize silage. The assay was sensitive to the effects of solvents, with 5% acetonitrile or 20% methanol causing a two-fold or greater increase in IC50. For analysis of silage samples, extracts were cleaned up by adsorbing potential matrix interferences onto a solid phase extraction column. The non-retained extract was then diluted with buffer to reduce solvent content prior to assay. Using this method, the limit of detection for PAX in dried silage was 15 µg/kg and the limit of quantification was 90 µg/kg. Recovery from samples spiked over the range of 100 to 1000 µg/kg averaged 106% ± 18%. The assay was applied to 86 maize silage samples, with many having detectable, but none having quantifiable, levels of PAX. The results suggest the CI-ELISA can be applied as a sensitive technique for the screening of PAX in maize silage.

  9. Development of a sensitive and specific epitope-blocking ELISA for universal detection of antibodies to human enterovirus 71 strains.

    Directory of Open Access Journals (Sweden)

    Fang He

    Full Text Available BACKGROUND: Human Enterovirus 71 (EV71 is a common cause of hand, foot and mouth disease (HFMD in young children. It is often associated with severe neurological diseases and mortalities in recent outbreaks across the Asia Pacific region. Currently, there is no efficient universal antibody test available to detect EV71 infections. METHODOLOGY/PRINCIPAL FINDING: In the present study, an epitope-blocking ELISA was developed to detect specific antibodies to human EV71 viruses in human or animal sera. The assay relies on a novel monoclonal antibody (Mab 1C6 that specifically binds to capsid proteins in whole EV71 viruses without any cross reaction to any EV71 capsid protein expressed alone. The sensitivity and specificity of the epitope-blocking ELISA for EV71 was evaluated and compared to microneutralization using immunized animal sera to multiple virus genotypes of EV71 and coxsackieviruses. Further, 200 serum sample from human individuals who were potentially infected with EV71 viruses were tested in both the blocking ELISA and microneutralization. Results indicated that antibodies to EV71 were readily detected in immunized animals or human sera by the epitope blocking ELISA whereas specimens with antibodies to other enteroviruses yielded negative results. This assay is not only simpler to perform but also shows higher sensitivity and specificity as compared to microneutralization. CONCLUSION: The epitope-blocking ELISA based on a unique Mab 1C6 provided highly sensitive and 100% specific detection of antibodies to human EV71 viruses in human sera.

  10. Evaluation of the indirect fluorescent antibody test for diagnosis of Babesia gibsoni infections in dogs. (United States)

    Yamane, I; Thomford, J W; Gardner, I A; Dubey, J P; Levy, M; Conrad, P A


    We determined the extent of the serologic cross-reactivity in the indirect fluorescent antibody (IFA) test for Babesia gibsoni, and the optimal cut-off titer for seropositivity in the test. The lowest titer to B gibsoni detected in a dog with naturally acquired clinical babesiosis was 1,280, and 7 of 12 dogs had titer between 10,240 and 20,480. Two experimentally infected normosplenic dogs developed high titer (40,960 to 81,920) to B gibsoni, and the same sera reacted in IFA tests for B canis (titer Neospora caninum (titer canis and T gondii had titer < or = 160 to B gibsoni. Dogs that were experimentally infected with N caninum had titer (80 to 10,240) to N caninum, but failed to have serologic reactivity to B gibsoni. Serologic titer of healthy dogs from Australia, a country where B gibsoni is not known to exist, was < or = 160 to B gibsoni. On the basis of these findings, a cut-off titer of 320 was considered to be appropriate for serodiagnosis of B gibsoni in dogs with clinical signs of babesiosis. A more conservative titer of 1,280 was established as the cut-off titer for seroepidemiologic studies based on relative costs and benefits of false-positive results and failure to isolate B gibsoni parasites after splenectomy and immunosuppression from a clinically normal dog with B gibsoni titer of 640.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. [Detection of influenza B virus antibodies in different age groups using hemagglutination inhibition tests]. (United States)

    Sonuvar, S; Kocabeyoğlu, O; Emekdaş


    Antibody levels against influenza B virus were investigated by using hemagglutination-inhibition (HA-I) tests in 402 sera obtained from different age groups. Hemagglutination antigens were obtained by production of influenza B virus (B/Singapur/LLC 6201) in trypsinized Madin Darby Bovine Kidney (MDBK) cell cultured and they were used in tests. In 355 out of 402 sera (88.3%) antibodies against influenza B virus were detected at titers varying between 1/20 and 1/1280. However in 47 sera (11.7%) no antibodies were detected at 1/20 titer. High titers of antibody (1/640-1/1280) were not detected in none of the sera obtained from an age group between 1 and 14. However high titer antibodies were detected in 15.6% of the sera from an age group between 26 and 35, in the 17.3% of the sera from a group above 50 years of age. Our findings suggest that the increase in the rates of seropositivity against influenza B virus depends on getting older and, that the infections by this virus may be widely seen in our country.

  12. Evaluation of Calypte AWARE HIV-1/2 OMT antibody test as a screening test in an Indian setting

    Directory of Open Access Journals (Sweden)

    Ingole N


    Full Text Available Purpose: Integrated counselling and testing centres (ICTC provide counselling and blood testing facilities for HIV diagnosis. Oral fluid tests provide an alternative for people whodo not want blood to be drawn. Also, it avoids the risk of occupational exposure. The goal of this study was to evaluate the utility of Calypte AWARE HIV-1/2 OMT antibody test as a screening test in an Indian setting. Materials and Methods: A cross-sectional study was carried out after ethics committee approval in 250 adult ICTC clients. Blood was collected and tested from these clients for HIV diagnosis as per routine policy and the results were considered as the gold standard. Also, after another written informed consent, oral fluid was collected from the clients and tested for the presence of HIV antibodies. Twenty five clients who had and 25 clients who had not completed their secondary school education (Group A and Group B, respectively were also asked to perform and interpret the test on their own and their findings and experiences were noted. Result: The sensitivity, specificity, PPV and NPV of the oral fluid antibody test were 100%, 98.51%, 94.11% and 100%, respectively. Seventy six percent of clients preferred oral fluid testing. Group B found it difficult to perform the test as compared to Group A and this difference was statistically significant (P ≤ 0.05. Conclusion: Oral fluid testing can be used as a screening test for HIV diagnosis; however, confirmation of reactive results by blood-based tests is a must.

  13. Real world experience with antiphospholipid antibody tests : how stable are results over time?

    NARCIS (Netherlands)

    Erkan, D; Derksen, WJM; Kaplan, [No Value; Sammaritano, L; Pierangeli, SS; Roubey, R; Lockshin, MD


    Objective: To determine the stability and the degree of variation of antiphospholipid antibody (aPL) results over time in a large cohort of well evaluated aPL positive patients; and to analyse factors contributing to aPL variation and the validity of aPL in a real world setting in which aPL tests ar

  14. Laboratory Evaluation of Three Rapid Diagnostic Tests for Dual Detection of HIV and Treponema pallidum Antibodies


    Humphries, Romney M.; Woo, Jennifer S.; Chung, Jun Ho; Sokovic, Anita; Bristow, Claire C; Jeffrey D Klausner


    The performance of three research-use-only, dual HIV and syphilis rapid diagnostic tests (RDTs) was evaluated for 150 patient serum samples and compared to reference HIV and Treponema pallidum antibody detection methods. The RDTs performed comparably, with sensitivities of 93 to 99% and specificities of 97 to 100%. The kappa statistic between the RDTs was 0.95.

  15. Antibody-Mediated Immunity against Tuberculosis: Implications for Vaccine Development


    Achkar, Jacqueline M; Casadevall, Arturo


    There is an urgent need for new and better vaccines against tuberculosis (TB). Current vaccine design strategies are generally focused on the enhancement of cell-mediated immunity. Antibody-based approaches are not being considered, mostly due to the paradigm that humoral immunity plays little role in the protection against intracellular pathogens. Here, we reappraise and update the increasing evidence for antibody-mediated immunity against Mycobacterium tuberculosis, discuss the complexity o...

  16. Antibody immobilization on a nanoporous aluminum surface for immunosensor development (United States)

    Chai, Changhoon; Lee, Jooyoung; Park, Jiyong; Takhistov, Paul


    A method of antibody (Ab) immobilization on a nanoporous aluminum surface for an electrochemical immunosensor is presented. To achieve good attachment and stability of Ab on an aluminum surface, aluminum was silanized with 3-aminopropyltryethoxysilane (APTES), and then covalently cross-linked to self-assembled layers (SALs) of APTES. Both the APTES concentration and the silanization time affected the formation of APTES-SALs as Ab immobilization. The formation of APTES-SALs was confirmed using the water contact angle on the APTES-SALs surface. The reactivity of APTES-SALs with Ab was investigated by measuring the fluorescence intensity of fluorescein isothiocyanate-labeled Ab-immobilized on the aluminum surface. Silanization of aluminum in 2% APTES for 4 h resulted in higher water contact angles and greater amounts of immobilized Ab than other APTES concentrations or silanization times. More Ab was immobilized on the nanoporous surface than on a planar aluminum surface. Electrochemical immunosensors developed on the nanoporous aluminum via the Ab immobilization method established in this study responded functionally to the antigen concentration in the diagnostic solution.

  17. Perl Testing A Developer's Notebook

    CERN Document Server

    Langworth, Ian


    Is there any sexier topic in software development than software testing? That is, besides game programming, 3D graphics, audio, high-performance clustering, cool websites, et cetera? Okay, so software testing is low on the list. And that's unfortunate, because good software testing can increase your productivity, improve your designs, raise your quality, ease your maintenance burdens, and help to satisfy your customers, coworkers, and managers. Perl has a strong history of automated tests. A very early release of Perl 1.0 included a comprehensive test suite, and it's only improved from th

  18. Development of a recombinant antibody towards PAPP-A for immunohistochemical use in multiple animal species

    DEFF Research Database (Denmark)

    Mikkelsen, Jakob H; Steffensen, Lasse B; Oxvig, Claus


    normal physiology and under different pathological conditions. However, antibodies for the detection of PAPP-A in non-human tissues have been lacking, although needed for use with several animal models which are currently being developed. To develop a monoclonal antibody suitable...... for the immunohistochemical detection of PAPP-A, we therefore selected a phage-derived scFv antibody, PAC1, specifically recognizing an epitope of PAPP-A, which is highly conserved between multiple animal species. We first converted this antibody into bivalent IgG, and verified its ability to recognize PAPP-A in sections...

  19. Developing test materials for dyscalculia

    DEFF Research Database (Denmark)

    Lindenskov, Lena; Bent, Lindhardt,

    Aims, requirements and context for the development of test materials for dyscalculia are analyzed. The test materials are to be used for Grade 4 pupils in Danish primary schools. Preliminary results are presented from focus group interview with adolescents and adults, who see themselves as being...

  20. Autologous HIV-1 neutralizing antibodies: emergence of neutralization-resistant escape virus and subsequent development of escape virus neutralizing antibodies

    DEFF Research Database (Denmark)

    Arendrup, M; Nielsen, C; Hansen, J E;


    The capacity of consecutive human sera to neutralize sequentially obtained autologous virus isolates was studied. HIV-1 was isolated three times over a 48-164-week period from three individuals immediately after seroconversion and from two individuals in later stages of infection. Development of ...... escape virus may be part of the explanation of the apparent failure of the immune system to control HIV infection.......The capacity of consecutive human sera to neutralize sequentially obtained autologous virus isolates was studied. HIV-1 was isolated three times over a 48-164-week period from three individuals immediately after seroconversion and from two individuals in later stages of infection. Development...... of neutralizing antibodies to the primary virus isolates was detected 13-45 weeks after seroconversion. Emergence of escape virus with reduced sensitivity to neutralization by autologous sera was demonstrated. The patients subsequently developed neutralizing antibodies against the escape virus but after a delay...

  1. The diagnostic sensitivity of dengue rapid test assays is significantly enhanced by using a combined antigen and antibody testing approach.

    Directory of Open Access Journals (Sweden)

    Scott R Fry


    Full Text Available BACKGROUND: Serological tests for IgM and IgG are routinely used in clinical laboratories for the rapid diagnosis of dengue and can differentiate between primary and secondary infections. Dengue virus non-structural protein 1 (NS1 has been identified as an early marker for acute dengue, and is typically present between days 1-9 post-onset of illness but following seroconversion it can be difficult to detect in serum. AIMS: To evaluate the performance of a newly developed Panbio® Dengue Early Rapid test for NS1 and determine if it can improve diagnostic sensitivity when used in combination with a commercial IgM/IgG rapid test. METHODOLOGY: The clinical performance of the Dengue Early Rapid was evaluated in a retrospective study in Vietnam with 198 acute laboratory-confirmed positive and 100 negative samples. The performance of the Dengue Early Rapid in combination with the IgM/IgG Rapid test was also evaluated in Malaysia with 263 laboratory-confirmed positive and 30 negative samples. KEY RESULTS: In Vietnam the sensitivity and specificity of the test was 69.2% (95% CI: 62.8% to 75.6% and 96% (95% CI: 92.2% to 99.8 respectively. In Malaysia the performance was similar with 68.9% sensitivity (95% CI: 61.8% to 76.1% and 96.7% specificity (95% CI: 82.8% to 99.9% compared to RT-PCR. Importantly, when the Dengue Early Rapid test was used in combination with the IgM/IgG test the sensitivity increased to 93.0%. When the two tests were compared at each day post-onset of illness there was clear differentiation between the antigen and antibody markers. CONCLUSIONS: This study highlights that using dengue NS1 antigen detection in combination with anti-glycoprotein E IgM and IgG serology can significantly increase the sensitivity of acute dengue diagnosis and extends the possible window of detection to include very early acute samples and enhances the clinical utility of rapid immunochromatographic testing for dengue.

  2. Antibody persistence and T-cell balance: Two key factors confronting HIV vaccine development


    Lewis, George K.; DeVico, Anthony L.; Gallo, Robert C.


    The quest for a prophylactic AIDS vaccine is ongoing, but it is now clear that the successful vaccine must elicit protective antibody responses. Accordingly, intense efforts are underway to identify immunogens that elicit these responses. Regardless of the mechanism of antibody-mediated protection, be it neutralization, Fc-mediated effector function, or both, antibody persistence and appropriate T-cell help are significant problems confronting the development of a successful AI...

  3. Diagnosis of canine echinococcosis: comparison of coproantigen and serum antibody tests with arecoline purgation in Uruguay. (United States)

    Craig, P S; Gasser, R B; Parada, L; Cabrera, P; Parietti, S; Borgues, C; Acuttis, A; Agulla, J; Snowden, K; Paolillo, E


    Echinococcus granulosus is one of the most important and widespread of the helminth zoonoses. Diagnosis of E. granulosus infection in dogs currently relies on arecoline dosing and detailed examination of the purge for adult worms. Two immunodiagnostic tests (ELISA) based on genus specific coproantigen detection or serum antibody (IgG, IgA and IgE) detection were compared against arecoline purgation for the detection of Echinococcus in naturally infected dogs in Uruguay. The coproantigen ELISA had a sensitivity of 76.9% compared with 34.6% for the serum IgG ELISA when assessed against 26 purge positive dogs (purge worm count range 1-4331). Coproantigen reactivity was positively correlated (r = 0.65) to purge worm count, with a threshold at over 20 worms. There was no positive correlation of antibody levels with worm counts. In 26 matched Echinococcus positive dog samples, the overall sensitivity of serological detection increased to 69.2% when seroreactivity for IgA and IgE antibodies were included and to 96.2% for both coproantigen and antibody assays combined. The detection of current infection of individual dogs with E. granulosus by coproantigen ELISA has the potential to replace arecoline purgation, while specific serum antibody detection should be useful in assessing Echinococcus exposure in dog populations.

  4. Seroprevalence of Mycoplasma gallisepticum antibody by ELISA and serum plate agglutination test of laying chicken

    Directory of Open Access Journals (Sweden)

    Md. Zulfekar Ali


    Full Text Available Aim: Mycoplasma gallisepticum (MG is important avian pathogen responsible for chronic respiratory disease of chicken and turkeys, which result in large economic loss for the poultry industry. The objectives of this study were determination of seroprevalence of MG antibody of commercial layer chicken at laying period in selected areas of Bangladesh. Materials and Methods: A total of 563 blood samples were collected randomly from selected commercial layer chickens at laying period during the period from July to December, 2013. Indirect enzyme linked immunosorbent assay (iELISA and serum plate agglutination (SPA test were performed to detect the presence of antibodies against MG. Results: Of 563 samples, 64.47% and 56.13% showed an overall prevalence of MG antibodies in iELISA and SPA test respectively. Prevalence of MG was recorded the highest (69.63% at 50-55 weeks of age compared with lowest (53.26% at 56-61 weeks of age (p<0.05. Significant (p<0.05 effect of breed were observed in the seroprevalence of MG infection in layer birds in the present study. The overall, 68.77%, 63.74% and 59.37% prevalence were found respectively in sonali, ISA Brown and White leg horn. The prevalence of MG antibodies was the highest (70.13% in December followed by November (68%, October (65.67%, August (63.46%, September (58.54% and July (51.78% month. The seroprevalence of MG antibodies was higher (69.63% in most of the large flocks and lower (56.82% in small flocks. Conclusion: Therefore, might be suggested that the commercial layer farms should be routinely checked to monitor MG infection and the reactor birds should be culled since MG organism has the potential to transmit vertically. The correlation between MG antibody in month and flock size was not significant (p=0.359 and p=0.868, respectively.

  5. Comparison of indirect fluorescent antibody test and the modified agglutination test for the detection of Toxoplasma gondii antibodies in stray dogs from Southern Brazil. (United States)

    de Almeida, Jonatas Campos; Frehse, Michelle Salmon; Navarro, Italmar Teodorico; Garcia, João Luis; Biondo, Alexander Welker; Freire, Roberta Lemos


    The aim of the present study was to determine the prevalence of antibodies to Toxoplasma gondii by two serological techniques in sera of 364 stray dogs from Brazil by immunofluorescence antibody test (IFAT, cut off point 1:16) and to the modified agglutination test (MAT, cut-off points 1:25 and 1:50). A total of 175/364 (48.07%) sera were positive by IFAT, and 108/364 (29.67%) and 85/364 (23.35%) were positive by MAT with cutoff points 1:25 and 1:50, respectively were positive by MAT. Cohen's Kappa Coefficient between IFAT and MAT was 0.81 (excellent) and 0.66 (substantial) with cutoff points 1:25 and 1:50, respectively. Using IFAT as gold standard, MAT sensitivity and specificity were 78% and 99% for 1:25 and 61% and 99% for 1:50, respectively. The results document of the usefulness of MAT for serological diagnosis because it does not require species-specific conjugate.

  6. Early developability screen of therapeutic antibody candidates using Taylor dispersion analysis and UV area imaging detection. (United States)

    Lavoisier, Alexandra; Schlaeppi, Jean-Marc


    Therapeutic antibodies represent one of the fastest growing segments in the pharmaceutical market. They are used in a broad range of disease fields, such as autoimmune diseases, cancer, inflammation and infectious diseases. The growth of the segment has necessitated development of new analytical platforms for faster and better antibody selection and characterization. Early quality control and risk assessment of biophysical parameters help prevent failure in later stages of antibody development, and thus can reduce costs and save time. Critical parameters such as aggregation, conformational stability, colloidal stability and hydrophilicity, are measured during the early phase of antibody generation and guide the selection process of the best lead candidates in terms of technical developability. We report on the use of a novel instrument (ActiPix/Viscosizer) for measuring both the hydrodynamic radius and the absolute viscosity of antibodies based on Taylor dispersion analysis and UV area imaging. The looped microcapillary-based method combines low sample consumption, fast throughput and high precision compared to other conventional methods. From a random panel of 130 antibodies in the early selection process, we identified some with large hydrodynamic radius outside the normal distribution and others with non-Gaussian Taylor dispersion profiles. The antibodies with such abnormal properties were confirmed later in the selection process to show poor developability profiles. Moreover, combining these results with those of the viscosity measurements at high antibody concentrations allows screening, with limited amounts of materials, candidates with potential issues in pre-formulation development.

  7. Maternal antibody transfer can lead to suppression of humoral immunity in developing zebra finches (Taeniopygia guttata). (United States)

    Merrill, Loren; Grindstaff, Jennifer L


    Maternally transferred antibodies have been documented in a wide range of taxa and are thought to adaptively provide protection against parasites and pathogens while the offspring immune system is developing. In most birds, transfer occurs when females deposit immunoglobulin Y into the egg yolk, and it is proportional to the amount in the female's plasma. Maternal antibodies can provide short-term passive protection as well as specific and nonspecific immunological priming, but high levels of maternal antibody can result in suppression of the offspring's humoral immune response. We injected adult female zebra finches (Taeniopygia guttata) with one of two antigens (lipopolysaccharide [LPS] or keyhole limpet hemocyanin [KLH]) or a control and then injected offspring with LPS, KLH, or a control on days 5 and 28 posthatch to examine the impact of maternally transferred antibodies on the ontogeny of the offspring's humoral immune system. We found that offspring of females exposed to KLH had elevated levels of KLH-reactive antibody over the first 17-28 days posthatch but reduced KLH-specific antibody production between days 28 and 36. We also found that offspring exposed to either LPS or KLH exhibited reduced total antibody levels, compared to offspring that received a control injection. These results indicate that high levels of maternal antibodies or antigen exposure during development can have negative repercussions on short-term antibody production and may have long-term fitness repercussions for the offspring.

  8. Antibodies against glucan, chitin, and Saccharomyces cerevisiae mannan as new biomarkers of Candida albicans infection that complement tests based on C. albicans mannan. (United States)

    Sendid, B; Dotan, N; Nseir, S; Savaux, C; Vandewalle, P; Standaert, A; Zerimech, F; Guery, B P; Dukler, A; Colombel, J F; Poulain, D


    Antibodies against Saccharomyces cerevisiae mannan (ASCA) and antibodies against synthetic disaccharide fragments of glucans (ALCA) and chitin (ACCA) are biomarkers of Crohn's disease (CD). We previously showed that Candida albicans infection generates ASCA. Here, we explored ALCA and ACCA as possible biomarkers of invasive C. albicans infection (ICI). ASCA, ALCA, ACCA, and Candida mannan antigen and antibody detection tests were performed on 69 sera obtained sequentially from 18 patients with ICIs proven by blood culture, 59 sera from CD patients, 47 sera from hospitalized subjects colonized by Candida species (CZ), and 131 sera from healthy controls (HC). ASCA, ALCA, and ACCA levels in CD and ICI patients were significantly different from those in CZ and HC subjects (PICI patients, these levels increased as infection developed. Using ASCA, ALCA, ACCA, and Platelia Candida tests, 100% of ICIs were detected, with the kinetics of the antibody response depending on the patient during the time course of infection. A large number of sera presented with more than three positive tests. This is the first evidence that the detection of antibodies against chitin and glucans has diagnostic value in fungal infections and that these tests can complement more specific tests. Future trials are necessary to assess the value of these tests in multiparametric analysis, as well as their pathophysiological relevance.

  9. A new rapid diagnostic test for detection of anti-Schistosoma mansoni and anti-Schistosoma haematobium antibodies

    Directory of Open Access Journals (Sweden)

    Coulibaly Jean T


    Full Text Available Abstract Background Parasitological methods are widely used for the diagnosis of schistosomiasis. However, they are insensitive, particularly in areas of low endemicity, and labour-intensive. Immunoassays based on detection of anti-schistosome antibodies have the merit of high sensitivity and recently a rapid diagnostic test (RDT, incorporating Schistosoma mansoni cercarial transformation fluid (SmCTF for detection of anti-schistosome antibodies in blood has been developed. Here, we assessed the diagnostic performance of the SmCTF-RDT for S. mansoni and S. haematobium infections by comparing it with microscopy for egg detection. Methods A cross-sectional survey was carried out in Azaguié, south Côte d’Ivoire. 118 pre-school-aged children submitted two stool and two urine samples, which were subjected to the Kato-Katz and urine filtration methods for the detection of S. mansoni and S. haematobium eggs, respectively. Urine was also subjected to a commercially available cassette test for S. mansoni, which detects circulating cathodic antigen. A finger-prick blood sample was used for the SmCTF-RDT for detection of anti-S. mansoni and anti-S. haematobium antibodies. Results The prevalence of both anti-S. mansoni and anti-S. haematobium antibodies was more than three times higher than the prevalence of infection estimated by egg detection under a microscope. Using quadruplicate Kato-Katz as the reference standard for the diagnosis of S. mansoni infection, the sensitivity, negative predictive value (NPV, and positive predictive value (PPV of the SmCTF-RDT was 75.0%, 84.2% and 22.5%, respectively. When two urine filtrations were considered as the reference standard for the diagnosis of S. haematobium infection, the sensitivity, NPV and PPV of SmCTF-RDT was 66.7%, 94.9% and 5.1%, respectively. The specificity of SmCTF-RDT, when using egg-detection as the reference standard, was estimated to be 34.4%. This low specificity may be a reflection of the

  10. Comparison of the latex agglutination test with the hemagglutination inhibition test, enzyme-linked immunosorbent assay, and neutralization test for detection of antibodies to rubella virus.


    Meegan, J M; Evans, B. K.; Horstmann, D. M.


    The ability of a rapid, latex agglutination test to diagnose rubella infection and to measure immune status was evaluated by comparison with the hemagglutination-inhibition (HAI) test, enzyme-linked immunosorbent assay (ELISA), and the neutralization (NT) test. The latex agglutination test accurately detected serological conversions in 74 pairs of sera representing 21 natural infections and 53 immunizations. The antibody levels of 276 sera from the general population were determined by latex ...

  11. Development and evaluation of a VP3-ELISA for the detection of goose and Muscovy duck parvovirus antibodies. (United States)

    Zhang, Yun; Li, Yongfeng; Liu, Ming; Zhang, Dabing; Guo, Dongchun; Liu, Chunguo; Zhi, Haidong; Wang, Xiaomei; Li, Gang; Li, Na; Liu, Shiguo; Xiang, Wenhua; Tong, Guangzhi


    The VP3-encoding gene of goose parvovirus (GPV) Ep22 strain was cloned and expressed in Escherichia coli. The GPV VP3-encoding gene was 1605 bp in length, and it encoded a 534 amino acid protein with a predicted molecular mass of 59.9 kDa. The VP3 fusion protein expressed in E. coli was detected by goose and Muscovy duck anti-parvovirus polyclonal sera. In addition, an ELISA (VP3-ELISA) using the VP3 protein as the coating antigen for the detection of antibodies to GPV in geese and antibodies to Muscovy duck parvovirus (MDPV) in Muscovy ducks was developed. Compared to the virus neutralization test, the specificity and sensitivity of the VP3-ELISA was 90.2% and 95.2% for goose sera and 91.8% and 96.7% for Muscovy duck sera, respectively. The VP3-ELISA did not react with the anti-sera to other goose or duck pathogens, indicating that this protein is specific for the reorganization of goose or duck anti-parvovirus antibodies. Cross-reactivity between immunoglobulin G antibodies from geese and Muscovy ducks was also tested, and the results reflected the phylogenetic distance between these two birds when using the ELISA. In conclusion, the VP3-ELISA is a sensitive and specific method for detecting antibodies against GPV or MDPV.

  12. Detection of Babesia divergens in southern Norway by using an immunofluorescence antibody test in cow sera

    Directory of Open Access Journals (Sweden)

    Røed Knut H


    Full Text Available Abstract Background The incidence of bovine babesiosis, caused by Babesia divergens (Apicomplexa: Piroplasmida has decreased markedly since the 1930 s, but may re-emerge as a consequence of climate change and changes in legislation and pasturing practices. This is a potentially serious disease, with both economical and animal welfare consequences. Therefore, there is a need to survey the distribution of B. divergens. Methods We tested sera from 306 healthy pastured cows from 24 farms along the southern Norwegian coast by using an indirect immunofluorescence IgG antibody test (IFAT. Fractions of seropositive cows were compared by calculating 95% CI. Results The results of this test showed that 27% of the sera were positive for B. divergens antibodies. The fraction of antibody-positive sera that we detected showed a two-humped distribution, with a high fraction of positives being found in municipalities in the western and eastern parts of the study area, while the municipalities between these areas had few or no positive serum samples. Conclusions Neither the farmers' observations nor the Norwegian Dairy Herd Recording System give an adequate picture of the distribution of bovine babesiosis. Serological testing of cows by using IFAT is a convenient way of screening for the presence of B. divergens in an area.

  13. Evaluation of a bovine antibody test for diagnosing Mycobacterium avium complex in patients with cystic fibrosis

    DEFF Research Database (Denmark)

    Qvist, Tavs; Pressler, Tacjana; Katzenstein, Terese L;


    INTRODUCTION: The aim of this study was to test a commercial bovine enzyme-linked immunosorbent assay for investigating antibody activity against Mycobacterium avium complex. METHODS: All patients at the Copenhagen Cystic Fibrosis (CF) Center who had culture for nontuberculous mycobacteria...... before and after culture conversion was performed in case patients. RESULTS: Out of 286 included subjects, six had clinical M. avium complex pulmonary disease at the time of sera sampling. These patients presented with higher antibody test values (P-value ... at ruling out pulmonary disease. Screening sera from patients with CF could guide clinicians to focus attention on patients at higher risk of M. avium complex pulmonary disease. Pediatr Pulmonol. 2016; 9999:XX-XX. © 2016 Wiley Periodicals, Inc....

  14. Interlaboratory testing of porcine sera for antibodies to porcine circovirus type 2

    DEFF Research Database (Denmark)

    McNair, I.; Marshall, M.; McNeilly, F.


    A panel of 20 porcine sera was distributed to 5 laboratories across Europe and Canada. Each center was requested to test the sera for the presence of porcine circovirus type 2 antibodies using the routine assays, indirect immunofluorescence assay (IFA) and indirect immunoperoxidase monolayer assa...... than did IFA, and paraformaldehyde gave higher titers than did acetone or ethyl alcohol. This report highlights the need for standardized procedures and biologicals for this virus....

  15. Red cell antibodies and low ionic strength: a study with enzyme-linked antiglobulin test. (United States)

    Leikola, J; Perkins, H A


    Alloantibody uptake on red blood cells was quantified with an accurate and reproducible enzyme-linked antiglobulin test. The uptake of anti-D, anti-Fy2 and anti-JK3 was markedly accelerated by low ionic strength salt solution (LISS) with a final ionic strength of 0.05 M. Near maximum uptake occurred within ten minutes at room temperature which corresponded to 60 minutes in saline at 37 C. Papain treatment of red blood cells increased the amount of anti-D bound, and there was no difference whether or not the papain-treated cells were suspended in LISS. In contrast, the uptake of IgG anti-A and anti-Leb was not accelerated by LISS, nor did LISS increase the rate of binding of antiblogulin to IgG antibody-coated red blood cells. We suggest this may be explained by the fact that the ABH and Lewis antigens (as well as bound IgG antibodies) extend beyond the "ionic cloud" surrounding the red blood cell. Antibody binding in the presence of albumin was approximately the same as in saline; but if the albumin was first dialyzed against LISS, the reaction was markedly accelerated and the final antibody uptake somewhat higher than in LISS alone.

  16. Serological survey on canine coronavirus antibodies in giant pandas by virus neutralization test

    Institute of Scientific and Technical Information of China (English)

    QIAOJun; XIAXian-zhu; YANGSong-tao; LIDe-sheng; HUGui-xue; GAOYu-wei; SUNHe-ting; ZHAOZhong-pen; XlEZhi-jing; YANFang; HEWen-qi; HUANGGen


    In order to survey the infectious situation of canine coronavirus (CCV) in giant panda population, a virus neutralization test detecting specific antibodies against CCV in giant panda's sera was established by using two-fold dilutions of serum and 100 TCID50 of the virus. The 62 sera samples of giant pandas, which were gathered from zoos and reserve region of Sichuan Province, China were detected. The neutralization antibody titer of 1:4 was recognized as the positive criterion, 8 sera samples were detected to be positive, and the positive rate was 12.9%. The titers of neutralizing antibody ranged from 1:8 to 1:32. It was the first comprehensive investigation on neutralization antibodies against CCV in giant panda population in China. The results of study showed that the infection of CCV in giant panda population was universal, which has posed a threat to the health of giant panda. Therefore, it is incumbent on us to study safe and effective vaccines to protect giant panda against CCV infection.

  17. Development and characterization of monoclonal antibodies to subgroup A avian leukosis virus. (United States)

    Qiu, Y; Li, X; Fu, L; Cui, Z; Li, W; Wu, Z; Sun, S


    Avian leukosis virus subgroup A (ALV-A) is a retrovirus which infects egg-type chickens and is the main pathogen of lymphoid leukosis (LL) and myeloid leukosis (ML). In order to greatly enhance the diagnosis and treatment of clinical avian leukemia, two monoclonal antibodies (MAbs) to ALV-A were developed by fusion between SP2/0 and spleen cells from mice immunized with expressed ALV-A env-gp85 protein. Using immunofluorescence assay (IFA), two MAbs reacted with ALV-A, but not with subgroups B and J of ALV. Western blot tests showed that molecular weight of ALV-A envelope glycoprotein recognized by MAbs was about 53 kD. Isotyping test revealed that two MAbs (A5C1 and A4C8) were IgG1 isotypes. These MAbs can be used for diagnosis and epidemiology of ALV-A.

  18. High-throughput antibody development and retrospective epitope mapping

    DEFF Research Database (Denmark)

    Rydahl, Maja Gro

    Plant cell walls are composed of an interlinked network of polysaccharides, glycoproteins and phenolic polymers. When addressing the diverse polysaccharides in green plants, including land plants and the ancestral green algae, there are significant overlaps in the cell wall structures. Yet...... the binding profile - in more or less high resolution - of two small molecular probes, 11 carbohydrate binding modules and 24 monoclonal antibodies. This was made possible by combining the HTP multiplexing capacity of carbohydrate microarrays with diverse glycomic tools, to downstream characterize...

  19. Temporal relation of antigenaemia and loss of antibodies to core antigens to development of clinical disease in HIV infection

    DEFF Research Database (Denmark)

    Pedersen, C; Nielsen, C M; Vestergaard, B F;


    A total of 276 sequential serum samples from 34 men with antibodies to the human immunodeficiency virus (HIV) followed up for two to seven years were analysed for HIV antigen and antibodies to the viral core and envelope proteins. Results were correlated with clinical outcome and CD4 T lymphocyte...... with antigenaemia compared with one out of 18 patients without antigenaemia. Low counts of CD4 cells (less than 0.5 X 10(9)/l) were found in 14 of the 16 patients with antigenaemia and five of the 18 without antigenaemia. Nine patients seroconverted to HIV during the study; two of these developed antigenaemia 14...... and 16 months after the estimated time of seroconversion. These results show that the late stages of HIV infection are characterised by increased production of antigen and a decrease in antibodies directed against the core protein. Antigenaemia indicates a poor prognosis; and as the antigen test...

  20. Development of a stable phosphoarginine analog for producing phosphoarginine antibodies. (United States)

    Ouyang, Han; Fu, Chuan; Fu, Songsen; Ji, Zhe; Sun, Ying; Deng, Peiran; Zhao, Yufen


    Protein phosphorylation is one of the most common and extensively studied post-translational modifications (PTMs). Compared to the O-phosphorylation on Ser, Thr and Tyr residues, our understanding of arginine phosphorylation is relatively limited, both in prokaryotes and eukaryotes, due to the intrinsic instability of phosphoarginine (pArg) and the lack of a feasible method to produce anti-pArg antibodies. We report the design and synthesis of a stable pArg analog, in which the labile N-P bond is replaced with a non-hydrolyzable C-P bond. Significantly, this analog was successfully used as a hapten to raise an immune response and the first mouse polyclonal antibody that specifically recognizes pArg-containing peptides and proteins was produced using analog-KLH conjugated as the immunogen. The generated antibody shows excellent specificity towards pArg-containing peptides and proteins, and could be used for a variety of biological detection methods. This provides us an invaluable tool to unravel the mystery of the biological function of pArg.

  1. Validation of serological tests for the detection of antibodies against Treponema pallidum in nonhuman primates.

    Directory of Open Access Journals (Sweden)

    Sascha Knauf


    Full Text Available There is evidence to suggest that the yaws bacterium (Treponema pallidum ssp. pertenue may exist in non-human primate populations residing in regions where yaws is endemic in humans. Especially in light of the fact that the World Health Organizaiton (WHO recently launched its second yaws eradication campaign, there is a considerable need for reliable tools to identify treponemal infection in our closest relatives, African monkeys and great apes. It was hypothesized that commercially available serological tests detect simian anti-T. pallidum antibody in serum samples of baboons, with comparable sensitivity and specificity to their results on human sera. Test performances of five different treponemal tests (TTs and two non-treponemal tests (NTTs were evaluated using serum samples of 57 naturally T. pallidum-infected olive baboons (Papio anubis from Lake Manyara National Park in Tanzania. The T. pallidum particle agglutination assay (TP-PA was used as a gold standard for comparison. In addition, the overall infection status of the animals was used to further validate test performances. For most accurate results, only samples that originated from baboons of known infection status, as verified in a previous study by clinical inspection, PCR and immunohistochemistry, were included. All tests, TTs and NTTs, used in this study were able to reliably detect antibodies against T. pallidum in serum samples of infected baboons. The sensitivity of TTs ranged from 97.7-100%, while specificity was between 88.0-100.0%. The two NTTs detected anti-lipoidal antibodies in serum samples of infected baboons with a sensitivity of 83.3% whereas specificity was 100%. For screening purposes, the TT Espline TP provided the highest sensitivity and specificity and at the same time provided the most suitable format for use in the field. The enzyme immune assay Mastblot TP (IgG, however, could be considered as a confirmatory test.

  2. Validation of serological tests for the detection of antibodies against Treponema pallidum in nonhuman primates. (United States)

    Knauf, Sascha; Dahlmann, Franziska; Batamuzi, Emmanuel K; Frischmann, Sieghard; Liu, Hsi


    There is evidence to suggest that the yaws bacterium (Treponema pallidum ssp. pertenue) may exist in non-human primate populations residing in regions where yaws is endemic in humans. Especially in light of the fact that the World Health Organizaiton (WHO) recently launched its second yaws eradication campaign, there is a considerable need for reliable tools to identify treponemal infection in our closest relatives, African monkeys and great apes. It was hypothesized that commercially available serological tests detect simian anti-T. pallidum antibody in serum samples of baboons, with comparable sensitivity and specificity to their results on human sera. Test performances of five different treponemal tests (TTs) and two non-treponemal tests (NTTs) were evaluated using serum samples of 57 naturally T. pallidum-infected olive baboons (Papio anubis) from Lake Manyara National Park in Tanzania. The T. pallidum particle agglutination assay (TP-PA) was used as a gold standard for comparison. In addition, the overall infection status of the animals was used to further validate test performances. For most accurate results, only samples that originated from baboons of known infection status, as verified in a previous study by clinical inspection, PCR and immunohistochemistry, were included. All tests, TTs and NTTs, used in this study were able to reliably detect antibodies against T. pallidum in serum samples of infected baboons. The sensitivity of TTs ranged from 97.7-100%, while specificity was between 88.0-100.0%. The two NTTs detected anti-lipoidal antibodies in serum samples of infected baboons with a sensitivity of 83.3% whereas specificity was 100%. For screening purposes, the TT Espline TP provided the highest sensitivity and specificity and at the same time provided the most suitable format for use in the field. The enzyme immune assay Mastblot TP (IgG), however, could be considered as a confirmatory test.

  3. Detailed examination of HLA antibody development on renal allograft failure and function. (United States)

    Zhu, Lan; Lee, Po-Chang; Everly, Matthew J; Terasaki, Paul I


    This is a long-term retrospective case-control study. Serial sera were collected over 17 years (1991-2008) from two groups comprised of 29 patients with allograft failure (250 sera) and 25 controls with functioning grafts (305 sera), each control matched by transplant date to one failure-group patient, and all patients tested with single antigen beads. The median follow-up for failure-group patients was 7.3 +/- 4.7 years and 11.8 +/- 4.4 years for controls. HLA alloantibodies appeared in 28 of the 29 failure-group patients (97%) and in 12 of the 25 controls (48%) (p failure (p = 0.001, p = 0.01). DSA against HLA-DQ antigen was found in 13 of 17 graft-failed patients who had received DQ-incompatible transplants (76%) compared with only one of 11 similarly DQ-mismatched control patients (9%) (p 5000) was higher in graft-failed patients than in graft-functioning patients. The time it took for antibodies to develop also differed between groups. HLA antibodies were formed sooner in the failure group compared with the controls (1.7 versus 3.7 years, P failure group patients developed antibodies within one year while none in the control group did. In conclusion, our study reinforces the observation that circulating de novo HLA alloantibodies predict adverse long-term kidney allograft outcomes. The significant negative impact of all alloantibodies calls for clinicians to monitor patients and implement removal therapy when alloantibody is first detected. This may prove a key step in the ongoing attempt to prevent chronic rejection and prolonging renal allograft survival.

  4. Antithyroglobulin antibody (United States)

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

  5. A neutralization test for specific detection of Nipah virus antibodies using pseudotyped vesicular stomatitis virus expressing green fluorescent protein. (United States)

    Kaku, Yoshihiro; Noguchi, Akira; Marsh, Glenn A; McEachern, Jennifer A; Okutani, Akiko; Hotta, Kozue; Bazartseren, Boldbaatar; Fukushi, Shuetsu; Broder, Christopher C; Yamada, Akio; Inoue, Satoshi; Wang, Lin-Fa


    Nipah virus (NiV) is a new zoonotic paramyxovirus that emerged in 1998 and is now classified in the genus Henipavirus along with the closely related Hendra virus (HeV). NiV is highly pathogenic in several vertebrate species including humans, and the lack of available vaccines or specific treatment restricts it to biosafety level 4 (BSL4) containment. A serum neutralization test was developed for measuring NiV neutralizing antibodies under BSL2 conditions using a recombinant vesicular stomatitis virus (VSV) expressing green fluorescent protein (GFP) and bearing the F and G proteins of NiV (VSV-NiV-GFP). The neutralization titers were obtained by counting GFP-expressing cells or by measuring fluorescence. The performance of this new assay was compared against the conventional test using live NiV with panels of sera from several mammalian species, including sera from NiV outbreaks, experimental infections, as well as HeV-specific sera. The results obtained with the VSV-NiV-GFP based test correlated with those obtained using live NiV. Using a 50% reduction in VSV-NiV-GFP infected cells as the cut-off for neutralization, this new assay demonstrated its potential as an effective tool for detecting NiV neutralizing antibodies under BSL2 containment with greater speed, sensitivity and safety as compared to the conventional NiV serum neutralization test.

  6. Comparison of latex and haemolysin tests for determination of anti-streptolysin O (ASO) antibodies.


    Curtis, G D; Kraak, W A; Mitchell, R G


    A latex agglutination test was compared with the micro-titration haemolysin inhibition method for the detection of anti-streptolysin O (ASO) antibodies in 428 serum samples. After slight modification of the latex method to produce maximal agglutination good agreement was shown between the results obtained by the two methods. The latex test had a sensitivity of 83.6%, a specificity of 93.3%, a predictive positive value of 86.5% and a predictive negative value of 91.6%. It was convenient, requi...

  7. Schmallenberg virus antibody development and decline in a naturally infected dairy cattle herd in Germany, 2011-2014. (United States)

    Wernike, Kerstin; Holsteg, Mark; Sasserath, Michael; Beer, Martin


    In late 2011, the novel insect-transmitted orthobunyavirus Schmallenberg virus (SBV) emerged in Central Europe. Since that year, a dairy cattle herd kept in the German region in which the virus was initially detected was continuously monitored. In order to evaluate the development of the within-herd seroprevalence, but also to assess the long-term persistence of antibodies against SBV in individual animals, blood samples of all cows older than 24 months were taken yearly after the respective vector season and serologically analyzed. In December 2011, in 74% of the tested animals SBV-specific antibodies were detectable. Additional scattered seroconversions were observed between the 2011 and 2012 vector seasons, thereafter all seronegative animals remained negative. Until December 2014, the intra-herd seroprevalence decreased to 58%. A total of 122 cows infected presumable in autumn 2011 were sampled every year, 9 of them became seronegative until December 2014. Consequently, though SBV-specific antibodies were detected in about 90% of the monitored animals for more than three years, a lifelong antibody-based immunity is not expected in every animal. The loss of anti-SBV antibodies in individual animals combined with the missing infection of young stock results in a declining herd seroprevalence and increases the risk of a renewed virus circulation to a greater extent within the next years.

  8. Development of a Coxsackievirus A16 neutralization assay based on pseudoviruses for measurement of neutralizing antibody titer in human serum. (United States)

    Jin, Jun; Ma, Hongxia; Xu, Lin; An, Dong; Sun, Shiyang; Huang, Xueyong; Kong, Wei; Jiang, Chunlai


    Serum neutralizing antibody titers are indicative of protective immunity against Coxsackievirus A16 (CV-A16) and Enterovirus 71 (EV71), the two main etiological agents of hand, foot and mouth disease (HFMD), and provide the basis for evaluating vaccine efficacy. The current CV-A16 neutralization assay based on inhibition of cytopathic effects requires manual microscopic examination, which is time-consuming and labor-intensive. In this study, a high-throughput neutralization assay was developed by employing CV-A16 pseudoviruses expressing luciferase for detecting infectivity in rhabdomyosarcoma (RD) cells and measuring serum viral neutralizing antibodies. Without the need to use infectious CV-A16 strains, the neutralizing antibody titer against CV-A16 could be determined within 15h by measuring luciferase signals by this assay. The pseudovirus CV-A16 neutralization assay (pCNA) was validated by comparison with a conventional CV-A16 neutralization assay (cCNA) in testing 174 human serum samples collected from children (age <5 years). The neutralizing antibody titers determined by these two assays were well correlated (R(2)=0.7689). These results suggest that the pCNA can serve as a rapid and objective procedure for the measurement of neutralizing antibodies against CV-A16.

  9. Preparation of Monoclonal Antibody and Development of Enzyme-linked Immunosorbent Assay Specific for Escherichia coli O157 in Foods

    Institute of Scientific and Technical Information of China (English)


    Objective To prepare monoclonal antibodies (Mab) and antisera specific for Escherichia coli (E.coli) O157, and to develop a sandwich enzyme-linked immunosorbent assay (ELISA) to detect E.coli O157 in foods. Methods Spleen cells from BALB/c mice immunized with the somatic antigen of E.coli O157:H7 were fused with murine Sp2/0 myeloma cells. The hybridoma cell line specific for E.coli O157 was established after having been subcloned. Antisera specific for E.coli O157 was prepared by intravenous injection into New Zealand rabbits with a stain of E.coli O157:H7. The sandwich ELISA was developed with the polyclonal antibody as the capture antibody and the Mab 3A5 as the detection antibody. The inoculated ground poultry meat and pasteurized milk were tested to confirm efficiency of the method. Results Mab 3A5 specific for E.coli O157 and O113:H21 belonged to subtype IgM. The ascetic titers of the antibody was 1:1×106. No cross-reactivity of the Mab was observed with strains of Salmonella spp, Yersinia enterocolitica, Shigella dysenteriae, etc. The purified polyclonal antibody had a titer of 1:1×105 with E.coli O157. The detection limit of this sandwich ELISA was 103-104 cfu E.coli O157/mL in pure culture with a high specificity, which was characterized by every non-O157 strain with negative response. With 10h enrichment procedure, E.coli O157:H7 recovered well from inoculated ground poultry meat and pasteurized milk at levels of 0.1 cfu/g and 0.1 cfu/mL. Conclusion Mab 3A5 specific for E.coli O157 and O113:H21 can be produced by immunizing BALB/c mice with a strain of E.coli O157:H7. Then a sandwich ELISA can be developed with the polyclonal antibody as the capture antibody and the Mab 3A5 as the detection antibody. The method is proved to be a sensitive and specific technique to detect low number of E.coli O157 in food.

  10. An ultra-sensitive monoclonal antibody-based fluorescent microsphere immunochromatographic test strip assay for detecting aflatoxin M1 in milk (United States)

    A rapid lateral flow fluorescent microspheres immunochromatography test strip (FMs-ICTS) has been developed for the detection of aflatoxin M1 (AFM1) residues in milk. For this purpose, an ultra-sensitive anti-AFM1 monoclonal antibody (MAb) 1D3 was prepared and identified. The IC50 value of the MA...

  11. An imaging diagnosis of cerebral paragonimiasis: CT and MR findings and correlation with ELISA antibody test

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    Chang, Kee Hyun; Cha, Sang Hoon; Han, Moon Hee; Kim, Hong Dae; Cho, Seung Yull; Kong, Yoon; Kang, Hyung Keun; Kim, Myung Soon [Seoul National University College of Medicine, Seoul (Korea, Republic of)


    To evaluate the CT and MR findings of cerebral paragonimiasis(PW) and to assess the diagnostic value of the specific antibody test by enzyme-linked immunosorbent assay(ELISA) for PW, 55 CT scans and 13 MR images of 57 patients with cerebral PW were reviewed retrospectively, and correlated with the serum/ CSF antibody levels. We divided the patients into three groups, early active (n=21), chronic(n=32), and combined stage(n=4), on the basis of CT/MR findings. In the groups of early active stage the most common and characteristic finding was multiple, conglomerated, ring-like enhancing lesion in the unilateral cerebral hemisphere, which was seen in 52% on CT and 44% on MR. Other non-specific findings included a solitary ring-like or irregular enhancing lesions, ill-defined low density lesions without enhancement, localized hemorrhage with or without enhancing lesions. In the group of chronic stage, there were multiple calcifications of various shapes, most commonly 1-2 cm sized round shape, and associated encephalomalacia. MR was superior to CT in detecting hemorrhage and in characterizing the central contents of ring-shaped calcifications, while it was inferior to CT in identifying small calcifications. Antibody levels of serum and CSF were positive in 86% and 82% in early active group, and in 48% and 31% in chronic stage,retrospectively.The positive rate was significantly different between the two groups (P=0.001). CT/MR findings were characteristic in only approximately half the cases in early active cerebral PW which can be cured by Praziquantel therapy. Therefore, antibody test by ELISA is recommended as a complementary tool, particularly in patients with non-specific imaging findings.

  12. Development and Characterization of Anti-Nitr9 Antibodies

    Directory of Open Access Journals (Sweden)

    Radhika N. Shah


    Full Text Available The novel immune-type receptors (NITRs, which have been described in numerous bony fish species, are encoded by multigene families of inhibitory and activating receptors and are predicted to be functional orthologs to the mammalian natural killer cell receptors (NKRs. Within the zebrafish NITR family, nitr9 is the only gene predicted to encode an activating receptor. However, alternative RNA splicing generates three distinct nitr9 transcripts, each of which encodes a different isoform. Although nitr9 transcripts have been detected in zebrafish lymphocytes, the specific hematopoietic lineage(s that expresses Nitr9 remains to be determined. In an effort to better understand the role of NITRs in zebrafish immunity, anti-Nitr9 monoclonal antibodies were generated and evaluated for the ability to recognize the three Nitr9 isoforms. The application of these antibodies to flow cytometry should prove to be useful for identifying the specific lymphocyte lineages that express Nitr9 and may permit the isolation of Nitr9-expressing cells that can be directly assessed for cytotoxic (e.g., NK function.

  13. Comparison of five commercial serological tests for the detection of anti-Chlamydia trachomatis antibodies. (United States)

    Baud, D; Regan, L; Greub, G


    Screening for Chlamydia trachomatis-specific antibodies is valuable in investigating recurrent miscarriage, tubal infertility and extrauterine pregnancy. We compared here the performance of immunofluorescence (IF) to four other commercial tests in detecting IgG antibodies directed against C. trachomatis: two enzyme-linked immunosorbent assays (ELISAs) using the major outer membrane protein (MOMP) as the antigen, commercialised respectively by Medac and R-Biopharm (RB), one ELISA using the chlamydial heat shock protein 60 (cHSP60) as the antigen (Medac), as well as a new automated epifluorescence immunoassay (InoDiag). A total of 405 patients with (n = 251) and without (n = 154) miscarriages were tested by all five tests. The prevalence of C. trachomatis-specific IgG antibodies as determined by the IF, cHSP60-Medac, MOMP-Medac, MOMP-RB and InoDiag was 14.3, 23.2, 14.3, 11.9 and 26.2%, respectively. InoDiag exhibited the highest sensitivity, whereas MOMP-RB showed the best specificity. Cross-reactivity was observed with C. pneumoniae using IF, MOMP-RB and InoDiag, and Parachlamydia acanthamoebae using the cHSP60 ELISA test. No cross-reactivity was observed between C. trachomatis and the other Chlamydiales (Neochlamydia hartmannellae, Waddlia chondrophila and Simkania negevensis). Given its high sensitivity, the new automated epifluorescence immunoassay from InoDiag represents an interesting alternative. The MOMP-based ELISA of R-Biopharm should be preferred for large serological studies, given the high throughput of ELISA and its excellent specificity.

  14. Paradoxical role of antibodies in dengue virus infections: considerations for prophylactic vaccine development. (United States)

    Acosta, Eliana G; Bartenschlager, Ralf


    Highly effective prophylactic vaccines for flaviviruses including yellow fever virus, tick-borne encephalitis virus and Japanese encephalitis virus are currently in use. However, the development of a dengue virus (DENV) vaccine has been hampered by the requirement of simultaneous protection against four distinct serotypes and the threat that DENV-specific antibodies might either mediate neutralization or, on the contrary, exacerbate disease through the phenomenon of antibody-dependent enhancement (ADE) of infection. Therefore, understanding the cellular, biochemical and molecular basis of antibody-mediated neutralization and ADE are fundamental for the development of a safe DENV vaccine. Here we summarize current structural and mechanistic knowledge underlying these phenomena. We also review recent results demonstrating that the humoral immune response triggered during natural DENV infection is able to generate neutralizing antibodies binding complex quaternary epitopes only present on the surface of intact virions.

  15. Development of 316v antibody enzyme-linked immunosorbent assay for detection of paratuberculosis in sheep. (United States)

    Gurung, R B; Begg, D J; Purdie, A C; Eamens, G J; Whittington, R J


    An enzyme-linked immunosorbent assay (ELISA) was developed and optimised using a Mycobacterium avium subspecies paratuberculosis (MAP) antigen prepared from a C strain (316v) passed through a French press. The optimised assay was evaluated with a panel of sera from MAP infected (n = 66) and uninfected (n = 1,092) sheep. Animals in the MAP infected category were positive on either tissue culture or histopathology but were of unknown serum antibody status. The diagnostic performance and cost of the assay were compared with those of a commercial ELISA (IDEXX). At 99.8% diagnostic specificity the assay showed a diagnostic sensitivity of 23% (95% CI: 15.1-35.8) compared with 36.4% (95% CI: 25.8-48.4) for the commercial ELISA (McNemar's test: chi-square 5.82, p ELISA for an equivalent number of tests, the multiple depending on the number of plates processed per run. For flock-level surveillance, to account for the lower sensitivity of the 316v ELISA compared with the commercial ELISA, sample sizes would be increased but the test cost would still be lower. The 316v assay will be useful for diagnosis of Johne's disease in sheep flocks, particularly in developing countries where labour costs are low relative to the cost of consumables.

  16. Biosimilar monoclonal antibodies: preclinical and clinical development aspects. (United States)

    Gonçalves, João; Araújo, Filipe; Cutolo, Maurizio; Fonseca, João Eurico


    Biological drugs and their originated biosimilars are large, highly complex molecules derived from living cells or organisms. Traditional medicines, by contrast, are usually simple molecules of low molecular weight, synthesised by chemical means. The distinct complexities and methods of manufacture create an important difference between biosimilars and conventional generic drugs: while chemical generics can be fully characterised as identical to the originator product, biosimilars cannot. In addition, biological therapies are inherently variable, creating unavoidable differences between even subsequent batches of the same product. An expiring patent does not necessarily mean that the manufacturing process of the originator product becomes available to the biosimilar developers (for instance, the relevant cell line clone and growth medium). Therefore, it cannot be guaranteed that biosimilar products are identical to their reference product on a molecular level. This difference has important implications for the regulation and licensing of biosimilars. While conventional generic drugs require only a limited comparison and demonstration of identical chemical structure to the reference product, biosimilars require far more rigorous testing. In general, there must be a thorough comparison of structural and functional characteristics between biosimilar and originator drug. Stepwise nonclinical in vitro and in vivo approaches are recommended to evaluate the similarity of both drugs and any identified micro-heterogeneities must then be assessed for their impact on safety and clinical performance. Subsequently, clinical pharmacokinetic (PK) studies need to be performed in order to demonstrate a similar PK profile, prior to conducting clinical efficacy trials.

  17. Alternative Water Processor Test Development (United States)

    Pickering, Karen D.; Mitchell, Julie L.; Adam, Niklas M.; Barta, Daniel; Meyer, Caitlin E.; Pensinger, Stuart; Vega, Leticia M.; Callahan, Michael R.; Flynn, Michael; Wheeler, Ray; Birmele, Michele; Lunn, Griffin; Jackson, Andrew


    The Next Generation Life Support Project is developing an Alternative Water Processor (AWP) as a candidate water recovery system for long duration exploration missions. The AWP consists of biological water processor (BWP) integrated with a forward osmosis secondary treatment system (FOST). The basis of the BWP is a membrane aerated biological reactor (MABR), developed in concert with Texas Tech University. Bacteria located within the MABR metabolize organic material in wastewater, converting approximately 90% of the total organic carbon to carbon dioxide. In addition, bacteria convert a portion of the ammonia-nitrogen present in the wastewater to nitrogen gas, through a combination of nitrification and denitrification. The effluent from the BWP system is low in organic contaminants, but high in total dissolved solids. The FOST system, integrated downstream of the BWP, removes dissolved solids through a combination of concentration-driven forward osmosis and pressure driven reverse osmosis. The integrated system is expected to produce water with a total organic carbon less than 50 mg/l and dissolved solids that meet potable water requirements for spaceflight. This paper describes the test definition, the design of the BWP and FOST subsystems, and plans for integrated testing.

  18. Alternative Water Processor Test Development (United States)

    Pickering, Karen D.; Mitchell, Julie; Vega, Leticia; Adam, Niklas; Flynn, Michael; Wjee (er. Rau); Lunn, Griffin; Jackson, Andrew


    The Next Generation Life Support Project is developing an Alternative Water Processor (AWP) as a candidate water recovery system for long duration exploration missions. The AWP consists of biological water processor (BWP) integrated with a forward osmosis secondary treatment system (FOST). The basis of the BWP is a membrane aerated biological reactor (MABR), developed in concert with Texas Tech University. Bacteria located within the MABR metabolize organic material in wastewater, converting approximately 90% of the total organic carbon to carbon dioxide. In addition, bacteria convert a portion of the ammonia-nitrogen present in the wastewater to nitrogen gas, through a combination of nitrogen and denitrification. The effluent from the BWP system is low in organic contaminants, but high in total dissolved solids. The FOST system, integrated downstream of the BWP, removes dissolved solids through a combination of concentration-driven forward osmosis and pressure driven reverse osmosis. The integrated system is expected to produce water with a total organic carbon less than 50 mg/l and dissolved solids that meet potable water requirements for spaceflight. This paper describes the test definition, the design of the BWP and FOST subsystems, and plans for integrated testing.

  19. Developing Tests of Visual Dependency (United States)

    Kindrat, Alexandra N.


    Astronauts develop neural adaptive responses to microgravity during space flight. Consequently these adaptive responses cause maladaptive disturbances in balance and gait function when astronauts return to Earth and are re-exposed to gravity. Current research in the Neuroscience Laboratories at NASA-JSC is focused on understanding how exposure to space flight produces post-flight disturbances in balance and gait control and developing training programs designed to facilitate the rapid recovery of functional mobility after space flight. In concert with these disturbances, astronauts also often report an increase in their visual dependency during space flight. To better understand this phenomenon, studies were conducted with specially designed training programs focusing on visual dependency with the aim to understand and enhance subjects ability to rapidly adapt to novel sensory situations. The Rod and Frame test (RFT) was used first to assess an individual s visual dependency, using a variety of testing techniques. Once assessed, subjects were asked to perform two novel tasks under transformation (both the Pegboard and Cube Construction tasks). Results indicate that head position cues and initial visual test conditions had no effect on an individual s visual dependency scores. Subjects were also able to adapt to the manual tasks after several trials. Individual visual dependency correlated with ability to adapt manual to a novel visual distortion only for the cube task. Subjects with higher visual dependency showed decreased ability to adapt to this task. Ultimately, it was revealed that the RFT may serve as an effective prediction tool to produce individualized adaptability training prescriptions that target the specific sensory profile of each crewmember.

  20. Evaluation of a direct immunofluorescent antibody (difma test using Leishmania genus - specific monoclonal antibody in the routine diagnosis of cutaneous leishmaniasis

    Directory of Open Access Journals (Sweden)

    Martha E. Chico


    Full Text Available A direct immunofluorescent antibody (DIFMA test using a Leishmania genus- specific monoclonal antibody was evaluated in the routine diagnosis of cutaneous leishmaniasis (CL in Ecuador. This test was compared with the standard diagnostic techniques of scrapings, culture and histology. Diagnostic samples were taken from a total of 90 active dermal ulcers from patients from areas of Ecuador known to be endemic for cutaneous leishmaniasis. DIFMA was positive in all lesions. It was shown to be significantly superior to standard diagnostic methods either alone or in combination. The sensitivity of DIFMA did not diminish with chronicity of lesions. This test proved to be extremely useful in the routine diagnosis of CL because it is highly sensitive, is easy to use and produces rapid results.

  1. Development and application of antibody microarray for white spot syndrome virus detection in shrimp

    Institute of Scientific and Technical Information of China (English)

    XU Xiaoli; SHENG Xiuzhen; ZHAN Wenbin


    Detecting white spot syndrome virus (WSSV) in shrimp in high efficiency and veracity is important for disease prevention in aquaculture.Antibody-based microarray is a novel proteomic technology that can meet the requirements.In this study,we developed an antibody microarray for WSSV-detection in a specific and parallel way at multiple samples.First,seven slides each with different modifications were characterized by atomic force microscope,and were compared in the efficiency of immobilizing proteins.Of the seven,3-dimensional structured agarose gel-modified slides were chosen appropriate for the microarray for having higher signal value and superior spot size.A purified rabbit anti-WSSV antibody was arrayed as the capture antibody of the microarray on the agarose gel-modified slides,and then the microarray slides were incubated in the tissue homogenate of sampled shrimp and the antibody-antigen complex was detected by Cy3-conjugated anti-WSSV monoclonal antibody.The results were measured by a laser chipscanner and analyzed with software.To obtain satisfied fluorescence signal intensity,optimal conditions were searched.The detection limit of the antibody microarray for WSSV is 0.62 μg/mL,with a proven long shelf life for 6 months at 4℃ or 8 months at -20℃.Furthermore,concordance between antibody microarray and traditional indirect ELISA reached 100% for WSSV detection.These results suggest that the antibody microarray could be served as an effective tool for diagnostic and epidemiological studies of WSSV.

  2. Choosing wisely: Review and commentary on anti-nuclear antibody (ANA) testing. (United States)

    Fritzler, Marvin J


    Choosing Wisely®: Next Steps in Improving Healthcare Value is an initiative of the American Board of Internal Medicine (ABIM) Foundation. The driving forces for the Choosing Wisely (CW) campaign include rising and unstainable health care expenditures and evidence that there is lack of fiscal stewardship of health care resources. The American College of Rheumatology and the Canadian Rheumatology Association published their top five Choosing Wisely recommendations, the first of which pertained to antinuclear antibodies (ANA) and ANA subserology testing. Concerns about the wasteful use of these tests prompted an analysis of the expenditures attributable to ANA testing as a proportion of total health care expenditures and based on a financial model was in the range of 0.00125%. It is suggested that if the sole use of ANA testing is to add evidence to support a diagnosis when the pre-test probability is high, then the ANA test has limited clinical value. Accordingly, the goal of ANA testing needs to be reconsidered and expanded beyond an approach to simply confirming a diagnosis with 'intention to treat' to a goal of case finding of 'pre- or early disease' with an 'intent to prevent' disease. This an area where more significant inroads can be made in preventing end organ disease and thereby reducing health care expenditures HCE. One CW recommendation that bears emphasizing is that, with a few possible exceptions, repeat ANA or ANA subserology testing has little clinical value in monitoring disease activity or predicting a flare.

  3. Development of mass spectrometry based techniques for the identification and determination of compositional variability in recombinant polyclonal antibody products. (United States)

    Persson, Pia; Engström, Anders; Rasmussen, Lone K; Holmberg, Erland; Frandsen, Torben P


    Recombinant polyclonal antibodies are a new class of protein biologics, combining a defined number of target-specific antibodies, developed for therapeutic use across various indications. Development, manufacture, and release of recombinant polyclonal antibodies as well characterized biological products have required development of new chemistry, manufacturing, and control (CMC) technologies. Sym001 is a recombinant polyclonal antibody product containing 25 unique antibodies specific for the Rhesus D antigen. Sym001 drug substance is manufactured using a single batch technology, Sympress. Here, we describe the development of two novel mass spectrometry based methods that allows identification of individual antibodies in the Sym001 drug substance, through the determination of unique marker peptides or antibody light chains. The two methods provide an unambiguous identification of the 25 unique antibodies comprised in the Sym001 drug substance. Furthermore, the light chain liquid chromatography-mass spectrometry (LC-MS) method has been developed to allow the determination of the relative distribution of the 25 antibodies. The light chain LC-MS method has demonstrated linearity, specificity, precision, and accuracy, thus qualifying it for use in the quality control of recombinant polyclonal antibodies for human use. The development of such quantitative methods is central for the development and quality control of additional therapeutic recombinant polyclonal antibody products.

  4. Antibody-membrane switch (AMS) technology for facile cell line development. (United States)

    Yu, Bo; Wages, John M; Larrick, James W


    Generation of high-productivity cell lines remains a major bottleneck in therapeutic antibody development. Conventional cell line development often depends on gene amplification methodologies using dihydrofolate reductase or glutamine synthetase. Higher productivity is associated with an increased gene copy number. However, lack of selection pressure under the conditions of large-scale manufacturing leads to clonal instability. We have developed a novel method for cell line development, antibody-membrane switch (AMS) technology, that does not rely on gene amplification. This fluorescence-activated cell sorting (FACS)-based, high-throughput method is facilitated by cell-surface antibody expression to rapidly and efficiently isolate high-producing cells. The switch between membrane expression and secretion is achieved by alternative splicing and specific DNA recombination. The antibody of interest is initially displayed on the cell surface to facilitate FACS. Isolated high-producing cells are then seamlessly transformed into production cells after removing the membrane-anchoring domain sequence with a DNA recombinase. AMS technology has been applied in a number of antibody cell line development projects, which typically last 2-3 months. The top production cell lines exhibit very high specific productivity of 40-60 pg/cell/day resulting in production titers of 2-4 g/l in 10-day batch culture.

  5. Development of a Recombinant Antibody with Specificity for Chelated Uranyl Ions

    Energy Technology Data Exchange (ETDEWEB)

    X. Li; A.M. Kriegel; T.C. Bishop; R.C. Blake; E. Figueiredo; H. Yu; D.A. Blake


    The goal of our project is to continue the development of new techniques for rapid, automated identification of radionuclides, metals, and chelators that may contaminant sur face and groundwater at DOE sites. One of the four specific aims of the present project is to develop new technologies in antibody engineering that will enhance our immunosensor program. Recombinant antibodies have potential advantages over monoclonal antibodies produced by standard hybridoma technology. The cloned genes represent a stable, recoverable source for antibody production. In addition, the recombinant format offers opportunities for protein engineering that enhances antibody performance and for studies that relate antibody sequence to binding activity. In this study, a hybridoma that synthesized an antibody (12F6) that recognized a 1:1 complex between 2,9-dicarboxyl-1,10- phenanthroline (DCP) and UO{sub 2}{sup 2+} was used as a source of RNA for the development of a recombinant (Fab){sub 2} fragment. RNA was isolated from the 12F6 hybridoma and the cDNA encoding the entire {kappa} light chain and the linked VH and C1 portions of the heavy chain were amplified from total RNA. cDNA sequences were verified by comparison with the N-terminal amino acid sequences of the light and heavy chains of the native 12F6 monoclonal antibody. A leader sequence and appropriate restriction sites were added to each chain, and the fragments were ligated into a commercial dicistronic vector (pBudCE4.1, Invitrogen, Inc.). COS-1 cells were transfected with this vector and the culture supernatant was assayed for activity and the (Fab){sub 2} protein. Cells transfected with vector containing 12F6 cDNA synthesized and secreted recombinant (Fab){sub 2} fragments that bound to the UO{sub 2}{sup 2+}-DCP complex with an affinity indistinguishable from that of a (Fab){sub 2} fragment prepared from the native antibody. Molecular models of the heavy and light chain variable domains were constructed according to the

  6. Enhanced performance of an innovative dengue IgG/IgM rapid diagnostic test using an anti-dengue EDI monoclonal antibody and dengue virus antigen. (United States)

    Lee, Jihoo; Kim, Young-Eun; Kim, Hak-Yong; Sinniah, Mangalam; Chong, Chom-Kyu; Song, Hyun-Ok


    High levels of anti-dengue IgM or IgG can be detected using numerous rapid diagnostic tests (RDTs). However, the sensitivity and specificity of these tests are reduced by changes in envelope glycoprotein antigenicity that inevitably occur in limited expression systems. A novel RDT was designed to enhance diagnostic sensitivity. Dengue viruses cultured in animal cells were used as antigens to retain the native viral coat protein. Monoclonal antibodies (mAbs) were then developed, for the first time, against domain I of envelope glycoprotein (EDI). The anti-dengue EDI mAb was employed as a capturer, and EDII and EDIII, which are mainly involved in the induction of neutralizing antibodies in patients, were fully available to bind to anti-dengue IgM or IgG in patients. A one-way automatic blood separation device prevented reverse migration of plasma and maximize the capture of anti-dengue antibodies at the test lines. A clinical evaluation in the field proved that the novel RDT (sensitivities of 96.5% and 96.7% for anti-dengue IgM and IgG) is more effective in detecting anti-dengue antibodies than two major commercial tests (sensitivities of 54.8% and 82% for SD BIOLINE; 50.4% and 75.3% for PanBio). The innovative format of RDT can be applied to other infectious viral diseases.

  7. Comparative evaluation of novel African swine fever virus (ASF) antibody detection techniques derived from specific ASF viral genotypes with the OIE internationally prescribed serological tests. (United States)

    Gallardo, C; Soler, A; Nieto, R; Carrascosa, A L; De Mia, G M; Bishop, R P; Martins, C; Fasina, F O; Couacy-Hymman, E; Heath, L; Pelayo, V; Martín, E; Simón, A; Martín, R; Okurut, A R; Lekolol, I; Okoth, E; Arias, M


    The presence of antibodies against African swine fever (ASF), a complex fatal notifiable OIE disease of swine, is always indicative of previous infection, since there is no vaccine that is currently used in the field. The early appearance and subsequent long-term persistence of antibodies combined with cost-effectiveness make antibody detection techniques essential in control programmes. Recent reports appear to indicate that the serological tests recommended by the OIE for ASF monitoring are much less effective in East and Southern Africa where viral genetic and antigenic diversity is the greatest. We report herein an extensive analysis including more than 1000 field and experimental infection sera, in which the OIE recommended tests are compared with antigen-specific ELISAs and immuno-peroxidase staining of cells (IPT). The antibody detection results generated using new antigen-specific tests, developed in this study, which are based on production of antigen fractions generated by infection and virus purification from COS-1 cells, showed strong concordance with the OIE tests. We therefore conclude that the lack of success is not attributable to antigenic polymorphism and may be related to the specific characteristics of the local breeds African pigs.

  8. Development of QCM Biosensor with Specific Cow Milk Protein Antibody for Candidate Milk Adulteration Detection

    Directory of Open Access Journals (Sweden)

    Setyawan P. Sakti


    Full Text Available Adulteration of goat milk is usually done using cow’s milk product. Cow milk is used as it is widely available and its price is cheaper compared to goat milk. This paper shows a development of candidate tools for milk adulteration using cow milk. A quartz crystal microbalance immunosensor was developed using commercial crystal resonator and polyclonal antibody specific to cow milk protein. A specific protein at 208 KDa is found only in cow milk and does not exist in goat milk. The existence of this protein can be used as an indicator of cow milk content in a target solution. To detect the PSS 208 kDa protein, antibody specific to the PSS 208 was developed. The purified antibody was immobilized on top of the sensor surface on a polystyrene layer. The fraction of the immobilized antibody on the sensor was found at 1.5% of the given antibody. Using a static reaction cell, the developed immunosensor could detect the specific cow milk protein in buffer solution. The detection limit is 1 ppm. A linear relationship between frequency change and specific protein of cow milk concentration is found from a concentration of 1 ppm to 120 ppm.

  9. Antidotes, antibody-mediated immunity and the future of pharmaceutical product development. (United States)

    Caoili, Salvador Eugenio C


    If new scientific knowledge is to be more efficiently generated and applied toward the advancement of health, human safety must be more effectively addressed in the conduct of research. Given the present difficulties of accurately predicting biological outcomes of novel interventions in vivo, the imperative of human safety suggests the development of novel pharmaceutical products in tandem with their prospective antidotes in anticipation of possible adverse events, to render the risks of initial clinical trials more acceptable from a regulatory standpoint. Antibody-mediated immunity provides a generally applicable mechanistic basis for developing antidotes to both biologicals and small-molecule drugs (such that antibodies may serve as antidotes to pharmaceutical agents as a class including other antibodies) and also for the control and prevention of both infectious and noninfectious diseases via passive or active immunization. Accordingly, the development of prophylactic or therapeutic passive-immunization strategies using antipeptide antibodies is a plausible prelude to the development of corresponding active-immunization strategies using peptide-based vaccines. In line with this scheme, global proliferation of antibody- and vaccine-production technologies, especially those that obviate dependence on the cold chain for storage and transport of finished products, could provide geographically distributed breakout capability against emerging and future health challenges.

  10. Evaluation of five screening tests licensed in Argentina for detection of hepatitis C virus antibodies

    Directory of Open Access Journals (Sweden)

    Viviana Ré


    Full Text Available This study was conducted to compare among the most recent generation of five screening tests licensed in Argentina, in order to evaluate which of the tests has the best sensitivity for detection of antibodies against hepatitis C virus (HCV. The tests analyzed were: Detect-HCV™ (3.0 Biochem ImmunoSystems, Canada; Hepatitis C EIA Wiener Lab., Argentina; Equipar HCV Ab, Italy; Murex HCV 4.0, UK and Serodia-HCV particles agglutination test, Japan. The results obtained showed high discrepancy between the different kits used and show that some of the tests assessed have a low sensitivity for anti-HCV detection in both chronic infections and early seroconversion, and indicate that among the commercially available kits in Argentina, Murex HCV 4.0 (UK and Serodia-HCV particles agglutination test (Japan have the best sensitivity for HCV screening. Although the sensitivity of the assays is the first parameter to be considered for blood screening, more studies should be carried out to assess the specificity of such assays.

  11. In silico design and performance of peptide microarrays for breast cancer tumour-auto-antibody testing

    Directory of Open Access Journals (Sweden)

    Andreas Weinhäusel


    Full Text Available The simplicity and potential of minimally invasive testing using sera from patients makes auto-antibody based biomarkers a very promising tool for use in cancer diagnostics. Protein microarrays have been used for the identification of such auto-antibody signatures. Because high throughput protein expression and purification is laborious, synthetic peptides might be a good alternative for microarray generation and multiplexed analyses. In this study, we designed 1185 antigenic peptides, deduced from proteins expressed by 642 cDNA expression clones found to be sero-reactive in both breast tumour patients and controls. The sero-reactive proteins and the corresponding peptides were used for the production of protein and peptide microarrays. Serum samples from females with benign and malignant breast tumours and healthy control sera (n=16 per group were then analysed. Correct classification of the serum samples on peptide microarrays were 78% for discrimination of ‘malignant versus healthy controls’, 72% for ‘benign versus malignant’ and 94% for ‘benign versus controls’. On protein arrays, correct classification for these contrasts was 69%, 59% and 59%, respectively. The over-representation analysis of the classifiers derived from class prediction showed enrichment of genes associated with ribosomes, spliceosomes, endocytosis and the pentose phosphate pathway. Sequence analyses of the peptides with the highest sero-reactivity demonstrated enrichment of the zinc-finger domain. Peptides’ sero-reactivities were found negatively correlated with hydrophobicity and positively correlated with positive charge, high inter-residue protein contact energies and a secondary structure propensity bias. This study hints at the possibility of using in silico designed antigenic peptide microarrays as an alternative to protein microarrays for the improvement of tumour auto-antibody based diagnostics.

  12. Development of antibody directed nanoparticles for cancer therapy (United States)

    Ivkov, R.; DeNardo, S. J.; Meirs, L. A.; Natarajan, A.; DeNardo, G. L.; Gruettner, C.; Foreman, A. R.


    The pharmacokinetics, tumor uptake, and biologic effects of inductively heating 111In-chimeric L6 (ChL6) monoclonal antibody (mAb)-linked iron oxide nanoparticle (bioprobes) by externally applied alternating magnetic fields (AMF) were studied in athymic mice bearing human breast cancer HBT 3477 xenografts. In addition, response was correlated with calculated total deposited heat dose. Methods: Using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide HCl, 111In-7,10-tetraazacyclododecane-N, N',N'',N'''-tetraacetic acid-ChL6 was conjugated to the carboxylated polyethylene glycol on dextran-coated iron oxide 20-nm particles, one to two mAbs per nanoparticle. After magnetic purification and sterile filtration, pharmacokinetics, histopathology, and AMF/bioprobe therapy were done using 111In-ChL6 bioprobe doses (20 mcg/2.2 mg ChL6/ bioprobe), i.v. with 50 mcg ChL6 in athymic mice bearing HBT 3477; a 153 kHz AMF was given 72 hours postinjection for therapy with amplitudes of 1,300, 1,000, or 700 Oe. Weights, blood counts, and tumor size were monitored and compared with control mice receiving nothing, or AMF, or bioprobes alone. Results: 111In-ChL6 bioprobe binding in vitro to HBT 3477 cells was 50% to 70% of that of 111In-ChL6. At 48 hours, tumor, lung, kidney, and marrow uptakes of the 111In-ChL6 bioprobes were not different from that observed in prior studies of 111In-ChL6. Significant therapeutic responses from AMF/bioprobe therapy were shown compared with no treatment. In addition, greatest therapeutic benefit was observed for the 700 Oe treatment cohort. Toxicity was only seen in the 1,300 Oe AMF cohort, with 4 of 12 immediate deaths associated with skin erythema and petechiae. Conclusion: This study shows that mAb-conjugated nanoparticles (bioprobes), when given i.v., escape into the extravascular space and bind to cancer cell membrane antigen.Thus, bioprobes can be used in concert with externally applied AMF to deliver thermoablative cancer therapy. Therapeutic benefit

  13. Cost-Effectiveness Analysis of Different Testing Strategies that Use Antibody Levels to Detect Chronic Hepatitis C in Blood Donors (United States)

    Granados-García, Víctor; Contreras, Ana M.; García-Peña, Carmen; Salinas-Escudero, Guillermo; Thein, Hla-Hla; Flores, Yvonne N.


    Aim. We conducted a cost-effectiveness analysis of seven hepatitis C virus (HCV) testing strategies in blood donors. Methods. Three of the seven strategies were based on HCV diagnosis and reporting guidelines in Mexico and four were from previous and current recommendations outlined by the CDC. The strategies that were evaluated determine antibody levels according to the signal-to-cut-off (S/CO) ratio and use reflex Immunoblot (IMB) or HCV RNA tests to confirm true positive (TP) cases of chronic HCV infection. Costs were calculated from the perspective of the Mexican Institute of Social Security (IMSS). A decision tree model was developed to estimate the expected number of true positive cases and costs for the base-case scenarios and for the sensitivity analyses. Results. Base-case findings indicate an extended dominance of the CDC-USA2 and CDC-USA4 options by the IMSS Mexico3 and IMSS-Mexico1 alternatives. The probabilistic sensitivity analyses results suggest that for a willingness-to-pay (WTP) range of $0–9,000 USD the IMSS-Mexico1 strategy is the most cost-effective of all strategies ($5,000 USD per TP). The IMSS-Mexico3, IMSS-Mexico2, and CDC-USA3 strategies are also cost-effective strategies that cost between $7,800 and $8,800 USD per TP case detected. The CDC-USA1 strategy was very expensive and not cost-effective. Conclusions. HCV antibody testing strategies based on the classification of two or three levels of the S/CO are cost-effective procedures to identify patients who require reflex IMB or HCV RNA testing to confirm chronic HCV infection. PMID:27159320

  14. Antibodies to Lactobacilli and Bifidobacteria in Young Children with Different Propensity to Develop Islet Autoimmunity

    Directory of Open Access Journals (Sweden)

    Ija Talja


    Full Text Available The intestinal microbiota is essential to the maturation and homeostasis of the immune system. Immunoblot assays were used to establish the prevalence of serum IgG, IgM, and IgA antibodies specific for Bifidobacterium adolescentis, Bifidobacterium longum, and Lactobacillus rhamnosus GG proteins in young children presenting with or without type 1 diabetes (T1D. We demonstrated that children between the ages of 6 and 12 months had a substantial increase in the frequency of IgG antibodies specific for L. rhamnosus GG proteins. We measured IgG, IgM, and IgA class antibody reactivity against B. adolescentis DSM 20083, B. adolescentis DSM 20086, and B. longum DSM 20088 proteins demonstrating significantly higher IgA responses against B. adolescentis DSM 20083 strain proteins in children who developed islet autoimmunity and T1D later in life. B. adolescentis strains showed more IgM type antibodies in children who developed T1D later in life, but the difference was not statistically significant. B. longum proteins were recognized by IgG and IgA antibodies to a higher extent compared to other bacteria studied. These results confirm that differences in immune reactivity against some commensal strains in young children may represent a different risk factor for developing T1D.

  15. Development of an antibody capture ELISA using inactivated Ebola Zaire Makona virus. (United States)

    Krähling, Verena; Becker, Dirk; Rohde, Cornelius; Eickmann, Markus; Eroğlu, Yonca; Herwig, Astrid; Kerber, Romy; Kowalski, Katharina; Vergara-Alert, Júlia; Becker, Stephan


    The 2014 Zaire Ebola virus (ZEBOV) outbreak in West Africa represents an international public health concern. Highly sensitive and precise diagnostic tools are needed. In the present study, we developed a ZEBOV-specific enzyme-linked immunosorbent assay (ELISA) using inactivated ZEBOV isolate Makona from March 2014. Mock antigen was used to address nonspecific binding. Specificity, reproducibility and precision were determined to measure assay performance. The ZEBOV ELISA proved to be specific (96 %), reproducible and precise (Intra-assay CV 8 %, Inter-assay CV 18 %). Using the human monoclonal antibody KZ52, we showed that the ELISA was able to detect conformation-specific antibodies. Monitoring antibody development in 29 PCR-positive EBOV disease (EVD) patients revealed seroconversion in all cases. In addition, the ELISA was used to detect ZEBOV glycoprotein (GP)-specific antibodies in a vaccinated volunteer from day 14 until 5 years post-vaccination with a VSV-ZEBOV candidate vaccine. The results demonstrate the high reproducibility, specificity and sensitivity of this newly developed ELISA, which is suitable for the detection of specific antibody responses directed against different ZEBOV proteins in EVD patients and against the ZEBOV surface glycoprotein GP in vaccinated individuals.

  16. Detection of leptospiral antibodies by microscopic agglutination test in north-east of Iran

    Institute of Scientific and Technical Information of China (English)

    Ehsanollah Sakhaee; Gholam Reza Abdollah pour


    Objective: To detect leptospiral antibodies by microscopic agglutination test (MAT) in north-east of Iran. Methods: This study was conducted to evaluate prevalence of human leptospiral infections by MAT, using six current reference strains of Leptospira interrogans in north-east of Iran. A total of 285 serum samples were collected from three north-east provinces of Iran, from December, 2009 to June, 2010. Results: Antibodies were detected at least against one serovar of Leptospira interrogans in 45 sera (15.79 %) among 285 samples at a dilution 1:100 or greater. Positive titers against more than one serovar were detected in 24 sera of the positive samples. Therefore, there were 75 positive reactions against different serovar of Leptospira interrogans. Positive titers were recorded against serovar icterohaemorrhagiae (31 samples), hardjo (26 samples), grippotyphosa (7 samples), pomona (5 samples), canicola (4 samples) and ballum (2 sample).Conclusions:In present study the most prevalent (Leptospira icterohaemorrhagiae) and the least prevalent (Leptospira ballum) serovar are different from previous studies. Maybe, species and prevalence of serovars change during the time in one area and between regions.

  17. The Anti-Acetylcholine Receptor Antibody Test in Suspected Ocular Myasthenia Gravis

    Directory of Open Access Journals (Sweden)

    Jung Jin Lee


    Full Text Available Aim. To estimate the clinical significance of anti-acetylcholine receptor antibody (anti-AChR-Ab levels in suspected ocular myasthenia gravis. Methods. In total, 144 patients complaining of fluctuating diplopia and ptosis were evaluated for serum levels of anti-acetylcholine receptor antibody and their medical charts were retrospectively reviewed. Subjects were classified into three groups: variable diplopia only, ptosis only, and both variable diplopia and ptosis. We investigated serum anti-AChR-Ab titer levels and performed thyroid autoantibody tests. Results. Patients’ chief complaints were diplopia (N=103, ptosis (N=12, and their concurrence (N=29. Abnormal anti-AChR-Ab was observed in 21 of 144 patients (14.1%. Between the three groups, mean age, number of seropositive patients, and mean anti-AChR-Ab level were not significantly different (P=0.224, 0.073, and 0.062, resp.. Overall, 27.5% of patients had abnormal thyroid autoantibodies. Conclusion. The sensitivity of anti-AChR-Ab was 14.1% in suspected ocular myasthenia gravis and seropositivity in myasthenia gravis patients showed a high correlation with the presence of thyroid autoantibodies.

  18. Evaluation of the LIAISON ANA screen assay for antinuclear antibody testing in autoimmune diseases. (United States)

    Ghillani, P; Rouquette, A M; Desgruelles, C; Hauguel, N; Le Pendeven, C; Piette, J C; Musset, L


    Antinuclear antibodies (ANA) are widely detected by immunofluorescence on HEp-2 cells in patients with connective tissue diseases and other pathological conditions. We evaluated the first-automated chemiluminescence immunoassay for the detection of ANA (LIAISON ANA screen, DiaSorin). This study was carried out simultaneously in two laboratories by testing 327 patient samples with clinically defined connective diseases, 273 routine samples for ANA screening, and 300 blood donors. A total of 268 out of 337 IIF-positive sera were positive with LIAISON ANA screen (79.5% of agreement) and 240 out of 263 IIF-negative sera were negative with LIAISON ANA screen (91.2% of agreement). After resolution of discrepant results, the concordance reached, respectively, 94.9% and 98.8%. The specificity was 99.3% and the sensitivity was 94%. Unlike results obtained by other ANA screening assays, we observed acceptable sensitivity and specificity. Despite the presence of HEp-2 cell extract, we failed to detect some antibodies as antinucleolar, antinuclear envelope, and antiproliferating cell nuclear antigen. This automated assay allows quick process to results and exhibits satisfactory sensitivity for the detection of the main ANA specificities of connective tissue diseases.

  19. Integrated Language Definition Testing: Enabling Test-Driven Language Development


    Kats, L.C.L.; Vermaas, R.; Visser, E.


    The reliability of compilers, interpreters, and development environments for programming languages is essential for effective software development and maintenance. They are often tested only as an afterthought. Languages with a smaller scope, such as domain-specific languages, often remain untested. General-purpose testing techniques and test case generation methods fall short in providing a low-threshold solution for test-driven language development. In this paper we introduce the notion of ...

  20. Are maternal antibodies really that important? Patterns in the immunologic development of altricial passerine house sparrows (Passer domesticus.

    Directory of Open Access Journals (Sweden)

    Marisa O King

    Full Text Available BACKGROUND: Maternal antibodies are believed to play an integral role in protecting immunologically immature wild-passerines from environmental antigens. This study comprehensively examines the early development of the adaptive immune system in an altricial-developing wild passerine species, the house sparrow (Passer domestics, by characterizing the half-life of maternal antibodies in nestling plasma, the onset of de novo synthesis of endogenous antibodies by nestlings, and the timing of immunological independence, where nestlings rely entirely on their own antibodies for immunologic protection. METHODOLOGY/PRINCIPAL FINDINGS: In an aviary study we vaccinated females against a novel antigen that these birds would not otherwise encounter in their natural environment, and measured both antigen-specific and total antibody concentration in the plasma of females, yolks, and nestlings. We traced the transfer of maternal antibodies from females to nestlings through the yolk and measured catabolisation of maternal antigen-specific antibodies in nestlings during early development. By utilizing measurements of non-specific and specific antibody levels in nestling plasma we were able to calculate the half-life of maternal antibodies in nestling plasma and the time point at which nestling were capable of synthesizing antibodies themselves. Based on the short half-life of maternal antibodies, the rapid production of endogenous antibodies by nestlings and the relatively low transfer of maternal antibodies to nestlings, our findings suggest that altricial-developing sparrows achieve immunologic independence much earlier than precocial birds. CONCLUSIONS/SIGNIFICANCE: To our knowledge, this is the first in depth analyses performed on the adaptive immune system of a wild-passerine species. Our results suggest that maternal antibodies may not confer the immunologic protection or immune priming previously proposed in other passerine studies. Further research needs

  1. Development of Multiple ELISAs for the Detection of Antibodies against Classical Swine Fever Virus in Pig Sera

    Institute of Scientific and Technical Information of China (English)

    Zhen-hua Yang; Ling Li; Zi-shu Pan


    The major immunogenic proteins (Ems,E2 and NS3) of classical swine fever virus (CSFV) (Shimen strain) were expressed in E.coli and purified by affinity chromatography.The recombinant antigens were applied to develop multiple enzyme-linked immunosorbent assays (ELISAs) for the detection of specific antibodies in pig sera.Optimum cut-off values were determined by receiver operating characteristic (ROC) analysis after testing 201 sera of vaccinated pigs and 64 negative sera of unvaccinated piglets.The multiple ELISAs were validated with 265 pig sera yielding high sensitivity and specificity in comparison with the virus neutralization results.The results demonstrated that multiple ELISAs can be a valuable tool for the detection of CSFV infection and serological surveys in CSFV-free countries or for the evaluation of the antibody responses in pigs induced by a live attenuated C-strain vaccination.

  2. Standardization of serological tests for detecting anti-Trypanosoma cruzi antibodies in dogs

    Directory of Open Access Journals (Sweden)

    M. A. Lauricella


    Full Text Available This paper reports on the standardization of four serological reactions currently used in human serodiagnosis for the detection of anti-Trypanosoma cruzi antibodies in naturally and experimentally infected dogs. Indirect immunofluorescence test (IFAT and hemagglutination test (IHAT were standardized, and complement fixation test (CFT and direct agglutination test (DAT were used for diagnostic confirmation. Four hundred and eighty one mongrel dogs that were studied by xenodiagnosis were used: (1 parasitemic dogs of two localities of endemic area (EA of Santiago del Estero province in Argentina (n = 134; (2 non-parasitemic dogs of the same area (n = 285; (3 dogs experimentally infected with T. cruzi in the patent period (n = 6; (4 non-infected dogs (n = 56 which were born in the city of Buenos Aires (BA, one non-EA for Chagas' disease. For IFAT, parasitemic dogs EA showed 95% of reactive sera. Non parasitemic dogs EA showed 77% of non reactive sera. None sera from BA were reactive for dilutions higher than four. For IHAT, 84% of sera of parasitemic dogs EA showed serological reactivity and among non parasitemic dogs BA, 61% were non reactive, while the remainder showed at most titres of 1/16. The cut-off titres for IFAT and IHAT were 1/16 and 1/32 respectively, and for CFT and DAT 1/1 and 1/128 respectively. Sensitivity for IFAT, IHAT, CF and DAT were 95%, 84%, 97% and 95% respectively.

  3. Seroprevalence of bovine leptospiral antibodies by microscopic agglutination test in Southeast of Iran

    Institute of Scientific and Technical Information of China (English)

    Mohammad Khalili; Ehsanollah Sakhaee; Mohammad Reza Aflatoonian; Gholamreza Abdollahpour; Saeed Sattari Tabrizi; Elham Mohammadi Damaneh; Sajad Hossini-nasab


    Objective:To evaluate serological findings of bovine leptospirosis which is a zoonotic disease with worldwide distribution caused by Leptospira interrogans. Methods: One hundred and sixty seven sera were collected from 9 commercial dairy herds in jiroft suburbs, from July to October 2011. Microscopic agglutination test (MAT) was used to evaluates serological findings of bovine leptospirosis in Jiroft suburb dairy farms, Kerman province, Iran. Results:Antibodies were found by MAT at least against one serovar of Leptospira interrogans in 29 samples (17.36%) among 167 sera at a dilution 1:100 or higher, and Leptospira pomona was the most prevalent serovar. Positive titers against more than one serovar were detected in 6 sera of the positive samples. Conclusion:This study is the first report of leptospirosis in Southeast Iran and showed that Leptospira pomona was the most and Leptospira icterohaemorrhagiae the least prevalent serovars in Southeast Iran.

  4. Development of a Recombinant Antibody-Based Treatment of Snakebites

    DEFF Research Database (Denmark)

    Engmark, Mikael; Laustsen, Andreas Hougaard; Andersen, Mikael Rørdam

    Antivenom for snakebites is produced by immunization of large mammals with snake venom using atraditional and expensive method developed in the 1890’s. Due to the animal origin, the products arehighly immunogenic and come with a high risk of adverse side effects such as serum sickness...

  5. [Development of immunoenzyme methods for detecting antibodies to Aujeszky's disease virus gB glycoprotein in swine serum]. (United States)

    Morenkov, O S


    Four ELISA methods have been developed for detecting antibodies to Aujeszky's disease virus (ADV) glycoprotein gB. Indirect ELISA is based on affinity-purified gB (affi-gB-ELISA); three blocking ELISAs: indirect blocking ELISA (lbgB-ELISA), direct blocking ELISA (db-gB-ELISA), and two-site "sandwich" ELISA (sb-gB-ELISA) are based on monoclonal antibodies to conservative immunodominant epitopes of gB. The specificities and sensitivities of ELISAs were compared with each other and with indirect ELISA based on purified ADV virions (vir-ELISA). Affi-gB ELISA, db-gB-ELISA, and sb-gB-ELISA possess 100% sensitivity, ib-gB-ELISA 98% sensitivity, and vir-ELISA 93% sensitivity. Affi-gB ELISA, ib-gB-ELISA, db-gB-ELISA, and sb-gB-ELISA possess 100% specificity and vir-ELISA 92% specificity. The efficiency of detection of ADV-specific antibodies by affi-gB ELISA, db-gB-ELISA, and sb-gB-ELISA was comparable to that of analogous commercial test. Since db-gB-ELISA is easier to perform than affi-gB-ELISA or sb-gB-ELISA, it is concluded to be the most appropriate test for detecting pigs infected with ADV among non-vaccinated animals.

  6. Development of an Indirect Competitive ELISA Based on Polyclonal Antibody for the Detection of Diethylstilbestrol in Water Samples

    Institute of Scientific and Technical Information of China (English)

    WANG,Wen-Jun; LING,Yun; XU,Ting; GAO,Hong-Bin; SHENG,Wei; LI,Ji


    An indirect competitive enzyme-linked immunosorbent assay (icELISA) based on polyclonal antibody for the estrogen diethylstilbestrol (DES) was developed. With this aim, two different haptens mono-O-3-carboxypropyldiethylstilbestrol (DES-CP) and mono-O-carboxymethyldiethylstilbestrol (DES-CM) with carboxylic group that preserve the molecular structure character of diethylstilbestrol were synthesized. The haptens were conjugated with the carrier proteins bovine serum albumin (BSA) by mixed-anhydride method for immunogen and conjugated with ovalbumin (OVA) by active ester method for coating antigen. Polyclonal antibodies for diethylstilbestrol were raised by immunizing mice with immune antigen DES-CP-BSA. Under optimized system, the lowest limit of detection (LLD) of diethylstilbestrol was 0.01 ng/mL, and IC50= 1.02 ng/mL. Its analogs were tested and no obvious cross-reactivity was found to anti-diethylstilbestrol antibody. DES-fortified water samples were determined by simple dilution to diminish the matrix effect. The comparison between the amount of DES estimated by ELISA and the amount added indicates good agreement for all water samples tested, with mean recovery values ranging from 86% to 120.2%.

  7. Development time of IgG antibodies to West Nile virus. (United States)

    Papa, Anna; Danis, Kostas; Tsergouli, Katerina; Tsioka, Katerina; Gavana, Elpida


    Following an outbreak of West Nile virus (WNV) infections in Greece during summer/autumn 2010, a study was conducted to investigate the patterns of WNV IgG reactivity in 255 patients with respect to the day of illness and the type of clinical syndrome. IgG antibodies were detectable after a mean of 8.1 ± 4.9 and 12.6 ± 11.3 days after onset of illness in neuroinvasive and non-neuroinvasive cases, respectively (p < 0.001), suggesting that a delay in the development of WNV IgG antibodies is seen in non-neuroinvasive cases.

  8. Thermally induced degradation pathways of three different antibody-based drug development candidates. (United States)

    Fincke, Anja; Winter, Jonas; Bunte, Thomas; Olbrich, Carsten


    Protein-based medicinal products are prone to undergo a variety of chemical and physical degradation pathways. One of the most important exogenous stress condition to consider during manufacturing, transport and storage processes is temperature, because antibody-based therapeutics are only stable in a limited temperature range. In this study, three different formats of antibody-based molecules (IgG1, a bispecific scFv and a fab fragment) were exposed to thermal stress conditions occurring during transport and storage. For evaluation, an analytical platform was developed for the detection and characterization of relevant degradation pathways of different antibody-based therapeutics. The effect of thermal stress conditions on the stability of the three antibody-based formats was therefore investigated using visual inspection, different spectroscopic measurements, dynamic light scattering (DLS), differential scanning calorimetry (DSC), electrophoresis, asymmetric flow field-flow fractionation (AF4) and surface plasmon resonance technology (SPR). In summary, thermal stress led to heterogeneous chemical and physical degradation pathways of all three antibody-based formats used. In addition, identical exogenous stress conditions resulted in different kinds and levels of aggregates and fragmentation products. This knowledge is fundamental for a systematic and successful stabilization of protein-based therapeutics by the use of formulation additives.

  9. Anti-idiotypic antibody: A new strategy for the development of a growth hormone receptor antagonist. (United States)

    Lan, Hainan; Zheng, Xin; Khan, Muhammad Akram; Li, Steven


    In general, traditional growth hormone receptor antagonist can be divided into two major classes: growth hormone (GH) analogues and anti-growth hormone receptor (GHR) antibodies. Herein, we tried to explore a new class of growth hormone receptor (GHR) antagonist that may have potential advantages over the traditional antagonists. For this, we developed a monoclonal anti-idiotypic antibody growth hormone, termed CG-86. A series of experiments were conducted to characterize and evaluate this antibody, and the results from a competitive receptor-binding assay, Enzyme Linked Immunosorbent Assays (ELISA) and epitope mapping demonstrate that CG-86 behaved as a typical Ab2β. Next, we examined its antagonistic activity using in vitro cell models, and the results showed that CG-86 could effectively inhibit growth hormone receptor-mediated signalling and effectively inhibit growth hormone-induced Ba/F3-GHR638 proliferation. In summary, these studies show that an anti-idiotypic antibody (CG-86) has promise as a novel growth hormone receptor antagonist. Furthermore, the current findings also suggest that anti-idiotypic antibody may represent a novel strategy to produce a new class of growth hormone receptor antagonist, and this strategy may be applied with other cytokines or growth factors.

  10. Expression of recombinant antibodies. (United States)

    Frenzel, André; Hust, Michael; Schirrmann, Thomas


    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.

  11. Development of an Enzyme Linked Immunosorbent Assay to Detect Chicken Parvovirus Specific Antibodies (United States)

    Here we report the development and application of an enzyme linked immunosorbent assay to detect parvovirus-specific antibodies in chicken sera. We used an approach previously described for other parvoviruses to clone and express viral structural proteins in insect cells from recombinant baculovirus...

  12. Development and Use of Fluorescent Antibody and qPCR Protocols for the Electrostatic Spore Trap (United States)

    Fluorescent antibody (FA) and qPCR protocols were evaluated for the newly developed aerobiological sampler (Ionic Spore Trap), which depends upon electrostatic deposition of particulates onto a 25 mm aluminum disk (stub). This device was originally designed for assessment of captured particulates by...

  13. Development of a Highly Protective Combination Monoclonal Antibody Therapy against Chikungunya Virus

    NARCIS (Netherlands)

    Pal, Pankaj; Dowd, Kimberly A.; Brien, James D.; Edeling, Melissa A.; Gorlatov, Sergey; Johnson, Syd; Lee, Iris; Akahata, Wataru; Nabel, Gary J.; Richter, Mareike K. S.; Smit, Jolanda M.; Fremont, Daved H.; Pierson, Theodore C.; Heise, Mark T.; Diamond, Michael S.


    Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes global epidemics of a debilitating polyarthritis in humans. As there is a pressing need for the development of therapeutic agents, we screened 230 new mouse anti-CHIKV monoclonal antibodies (MAbs) for their ability to inhibit

  14. Sequential measurement of anti-platelet antibodies in a patient who developed EDTA-dependent pseudothrombocytopenia. (United States)

    Edelman, B; Kickler, T


    Ethylenediaminetetraacetic acid (EDTA)-dependent pseudothrombocytopenia is the occurrence of a falsely low platelet count caused by antibodies that agglutinate platelets in the presence of EDTA. If unrecognized, it may result in the erroneous diagnosis of thrombocytopenia and possible inappropriate therapy. It has been noted that this phenomenon tends to appear in hospitalized patients after an initially normal platelet count, but sequential measurements of anti-platelet antibody have not been reported. The case of a patient who developed EDTA-dependent pseudothrombocytopenia approximately 1 week after being hospitalized for severe trauma is described. Anti-platelet antibodies were not detected on admission by a radiolabeled antiglobulin technique but were shown to increase in titer concurrent with the appearance of EDTA-dependent pseudothrombocytopenia.

  15. Test-driven development with Django

    CERN Document Server

    Harvey, Kevin


    This book is for Django developers with little or no knowledge of test-driven development or testing in general. Familiarity with the command line, setting up a Python virtual environment, and starting a Django project are assumed.

  16. Development of a double-monoclonal antibody sandwich ELISA: Tool for chicken interferon-γ detection ex vivo (United States)

    Dai, Hua; Xu, Zheng-zhong; Wang, Meiling; Chen, Jun-hua; Chen, Xiang; Pan, Zhi-ming; Jiao, Xin-an


    The aim of the present work was to develop reagents to set up a chicken interferon-γ (ChIFN-γ) assay. Four monoclonal antibodies (mAbs) specific for ChIFN-γ were generated to establish sandwich ELISA based on 2 different mAbs. To improve the detection sensitivity of ChIFN-γ, a double-monoclonal antibody sandwich ELISA was developed using mAb 3E5 as capture antibody and biotinylated mAb 3E3 as a detection reagent. The results revealed that this ELISA has high sensitivity, allowing for the detection of 125 to 500 pg/mL of recombinant ChIFN-γ, and also has an excellent capacity for detecting native ChIFN-γ. This ELISA was then used to detect ChIFN-γ level in chickens immunized with a Newcastle disease virus (NDV) vaccine, the immunized chicken splenocytes were stimulated by NDV F protein as recall antigen. From our results, it appears that the sensitivity range of this sandwich ELISA test is adequate to measure the ex vivo release of ChIFN-γ. PMID:27127340

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

    Directory of Open Access Journals (Sweden)

    Mei-Liang Huang

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

  18. Antinuclear antibody testing in pleural fluid for the diagnosis of lupus pleuritis. (United States)

    Porcel, J M; Ordi-Ros, J; Esquerda, A; Vives, M; Madroñero, A B; Bielsa, S; Vilardell-Tarrés, M; Light, R W


    We sought to determine whether measuring antinuclear antibodies (ANA) and their specificities [dsDNA, extractable nuclear antigens (ENA)] on pleural fluid may contribute to the differential diagnosis of pleural effusions. ANA were tested by indirect immunofluorescence on Hep-2 cells in the pleural fluid of 266 patients with effusions of different etiologies, including 15 lupus pleuritis. The cutoff value for diagnostic use was set at 1:160. Pleural fluid analysis of specific autoantibodies, such as anti-dsDNA and anti-ENA, was also performed if a positive ANA test was obtained. All patients with lupus pleurisy and 16 of 251 (6.4%) patients with pleural effusions secondary to other causes were ANA positive. Fifty-six percent of the positive ANAs in non-lupus pleural fluids were due to neoplasms. The pleural fluid ANA titers were low (pleuritis from non-lupus etiologies, the absence of pleural fluid anti-dsDNA or anti-ENA favored the latter. ANAs in pleural fluid provided no additional diagnostic information beyond that obtained by the measurement in serum and, therefore, these tests need not be routinely performed on pleural fluid samples. However, in patients with SLE and a pleural effusion of uncertain etiology, lack of ANAs or specific autoantibodies in pleural fluid argues against the diagnosis of lupus pleuritis.

  19. Introduction to the application of QbD principles for the development of monoclonal antibodies. (United States)

    Finkler, Christof; Krummen, Lynne


    Quality by Design (QbD) is a global regulatory initiative with the goal of enhancing pharmaceutical development through the proactive design of pharmaceutical manufacturing process and controls to consistently deliver the intended performance of the product. The principles of pharmaceutical development relevant to QbD are described in the ICH guidance documents (ICHQ8-11). An integrated set of risk assessments and their related elements developed at Roche/Genentech were designed to provide an overview of product and process knowledge for the production of a recombinant monoclonal antibody. This chapter introduces a publication series on the application of Quality by Design for biopharmaceuticals, with a focus on the development of recombinant monoclonal antibodies. The development of and overview on the QbD concept applied by Roche and Genentech is described and essential QbD elements are presented.

  20. Mobile Router Developed and Tested (United States)

    Ivancic, William D.


    The NASA Glenn Research Center, under a NASA Space Act Agreement with Cisco Systems, has been performing joint networking research to apply Internet-based technologies and protocols to space-based communications. As a result of this research, NASA performed stringent performance testing of the mobile router, including the interaction of routing and the transport-level protocol. In addition, Cisco Systems developed the mobile router for both commercial and Government markets. The code has become part of the Cisco Systems Internetworking Operating System (IOS) as of release 12.2 (4) T--which will make this capability available to the community at large. The mobile router is software code that resides in a network router and enables entire networks to roam while maintaining connectivity to the Internet. This router code is pertinent to a myriad of applications for both Government and commercial sectors, including the "wireless battlefield." NASA and the Department of Defense will utilize this technology for near-planetary observation and sensing spacecraft. It is also a key enabling technology for aviation-based information applications. Mobile routing will make it possible for information such as weather, air traffic control, voice, and video to be transmitted to aircraft using Internet-based protocols. This technology shows great promise in reducing congested airways and mitigating aviation disasters due to bad weather. The mobile router can also be incorporated into emergency vehicles (such as ambulances and life-flight aircraft) to provide real-time connectivity back to the hospital and health-care experts, enabling the timely application of emergency care. Commercial applications include entertainment services, Internet protocol (IP) telephone, and Internet connectivity for cruise ships, commercial shipping, tour buses, aircraft, and eventually cars. A mobile router, which is based on mobile IP, allows hosts (mobile nodes) to seamlessly "roam" among various IP

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

    Energy Technology Data Exchange (ETDEWEB)

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


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

  2. Perceived Empathy of Service Providers Mediates the Association between Perceived Discrimination and Behavioral Intention to Take Up HIV Antibody Testing Again among Men Who Have Sex with Men



    HIV antibody testing is a key measure of HIV prevention for men who have sex with men (MSM). The World Health Organization recommends sexually active and at-risk MSM to take up HIV antibody testing regularly. This study aimed to investigate the prevalence of behavioral intention to take up HIV antibody testing in the next six months among Hong Kong MSM who were ever-testers. An anonymous cross-sectional survey recruited 326 MSM who had taken up HIV antibody testing from gay-friendly venues an...

  3. Should we offer routine hepatitis C antibody testing in men who have sex with men?

    Directory of Open Access Journals (Sweden)

    Christopher Ward


    Full Text Available Introduction: There has been a significant rise in the number of HIV positive men who have sex with men (MSM co-infected with hepatitis C (HCV. Most infections are thought to occur through high risk sexual practices, exacerbated by drug use. Previous data has suggested no need for routine screening in HIV negative MSM. We looked at HCV antibody testing and HCV risk assessment in all MSM clinic attenders as part of a Public Health England initiative. Materials and Methods: Routine HCV antibody testing was offered to all MSM attending a large inner city sexual health clinic from April to June 2014. Patients were asked to fill in a questionnaire assessing HCV risk. Demographic data, HIV status and STI results were collected and compared. Results: We collected 471 HCV risk assessment questionnaires during the eight-week period. The median age was 34 (range 18–71 and 403 (85.6% were White British. Ten (2.1% patients were known to be HCV positive, of which 3 were on treatment and 5 (1.1% had cleared HCV. One hundred and forty-nine (31.6% patients were HIV negative, 254 (53.9% were HIV positive and 68 (14.5% had unknown HIV status at time of clinic visit. In the last three months 151 (32.1% reported unprotected receptive anal intercourse, 58 (12.3% reported group sex, 11 (2.3% reported receptive fisting and 32 (6.8% reported more than 10 partners. Eighty-seven (18.5% patients had shared notes/straws to snort drugs and 29 (6.2% reported injecting drugs or slamming. One hundred and forty-two (30.0% patients reported recreational drug use in the last 12 months, with cocaine, methadrone and ketamine most popular. One hundred and fifteen (24.4% patients reported sex under the influence of recreational drugs. There were no statistical differences between HIV positive and HIV negative patients in their risk, sexual behaviour and drug use. STI screens were performed on 269 patients with nine (3.3% new HIV diagnoses, four (1.5% early syphilis, and 28 (10

  4. Development of an enzyme immunoassay using a monoclonal antibody against the psychoactive diterpenoid salvinorin A. (United States)

    Paudel, Madan Kumar; Shirota, Osamu; Sasaki-Tabata, Kaori; Tanaka, Hiroyuki; Sekita, Setsuko; Morimoto, Satoshi


    Salvinorin A (1), the main active constituent in Salvia divinorum, is a highly selective kappa-opioid receptor agonist with hallucinogenic effects, which is regulated in several countries. In the present study, a monoclonal antibody (mAb) against 1 was prepared, and an indirect competitive enzyme-linked immunosorbent assay (icELISA) system was developed for the detection of salvinorins. To raise mAbs against 1, salvinorin B (2) hemisuccinate was synthesized and used to prepare the immunogen 2-bovine serum albumin conjugate. This technique was used to prepare a hybridoma cell line, 3D5, which secreted a mAb that recognized 1. The mAb was shown to have specificity for 1 and other salvinorins in cross-reactivity tests. The intra-assay calibration range by icELISA using the mAb against 1 was 0.0195-0.625 μg/mL. After validating the icELISA using intra- and interassays, a recovery experiment and analysis of several plants in the family Lamiaceae, including S. divinorum, confirmed that the analytical method based on ELISA is not only simple but also precise, accurate, sensitive, and sufficiently reliable. The results indicate that icELISA is a useful tool in the identification of S. divinorum.

  5. Chikungunya virus RNA and antibody testing at a National Reference Laboratory since the emergence of Chikungunya virus in the Americas. (United States)

    Prince, Harry E; Seaton, Brent L; Matud, Jose L; Batterman, Hollis J


    Since first reported in the Americas in December 2013, chikungunya virus (CHIKV) infections have been documented in travelers returning from the Caribbean, with many cases identified by CHIKV antibody and/or RNA testing at our laboratory. We used our large data set to characterize the relationship between antibody titers and RNA detection and to estimate IgM persistence. CHIKV RNA was measured by nucleic acid amplification and CHIKV IgG/IgM by indirect immunofluorescence. Of the 1,306 samples submitted for RNA testing in January through September 2014, 393 (30%) were positive; for 166 RNA-positive samples, CHIKV antibody testing was also ordered, and 84% were antibody negative. Of the 6,971 sera submitted for antibody testing in January through September 2014, 1,811 (26%) were IgM positive; 1,461 IgM positives (81%) were also IgG positive. The relationship between the CHIKV antibody titers and RNA detection was evaluated using 376 IgM-positive samples (138 with RNA testing ordered and 238 deidentified and tested for RNA). RNA detection showed no significant association with the IgM titer but was inversely related to the IgG titer; 63% of the IgG negative sera were RNA positive, compared to 36% of sera with low IgG titers (1:10 to 1:80) and 16% with IgG titers of ≥1:160. Using second-sample results from 62 seroconverters, we estimated that CHIKV IgM persists for 110 days (95% confidence interval, 78 to 150 days) after the initial antibody-negative sample. These findings indicate that (i) RNA detection is more sensitive than antibody detection early in CHIKV infection, (ii) in the absence of RNA results, the IgG titer of the IgM-positive samples may be a useful surrogate for viremia, and (iii) CHIKV IgM persists for approximately 4 months after symptom onset.

  6. Development of a high-throughput opsonophagocytic assay for the determination of functional antibody activity against Streptococcus pyogenes using bioluminescence. (United States)

    Lorenz, Natalie; Loh, Jacelyn M S; Moreland, Nicole J; Proft, Thomas


    The lack of standardised protocols for the assessment of functional antibodies has hindered Streptococcus pyogenes research and the development of vaccines. A robust, high throughput opsonophagocytic bactericidal assay to determine protective antibodies in human and rabbit serum has been developed that utilises bioluminescence as a rapid read out.

  7. [Evaluation of allergen-specific IgE antibodies by a newly developed mast allergy system]. (United States)

    Nakagawa, T; Iwasaki, E; Baba, M; Matsushita, T; Baba, S; Ito, K; Miyamoto, T


    MAST, which stand for multiple antigen simultaneous test, uses enzyme-linked anti-human IgE and chemiluminogenic substate to determine IgE. This system is characterized by simultaneous analysis of multiple allergen items, up to 35, together with total IgE determination. We evaluated usefulness of this MAST system using 191 serum samples obtained from patients with bronchial asthma, allergic rhinitis and/or atopic dermatitis. It was found that there were statistically significant correlations between IgE antibody quantification by MAST and RAST in 24 out of 35 allergen items, with correlation coefficients more than r = 0.60. These included Dermatophagoides farinae and pteronyssinus, Japanese cedar pollen, orchard grass, Alternaria, Candida as inhalant allergens; egg white, milk, soybeans, wheat and rice as food allergens. It was also evaluated how many allergen-specific IgE antibodies could be detected in one serum sample. More than six allergen-specific IgE antibodies were simultaneously detected in 33% of 191 cases, indicating the importance of multiple-allergen analysis. These results indicate the clinical usefulness of the MAST allergy system in detecting IgE antibodies in allergic subjects.

  8. Rapid identification of vibrio-cholerae O1 by coaglutination test using mono-specifis antibody

    Directory of Open Access Journals (Sweden)

    Bazargan SA


    Full Text Available In our investigation, rabbit hyper-immune serum to V.cholerae ogawa was absorbed with V.cholerae inaba whole-cells and vice versa. Applying ammonium sulphate precipitation method, mono-specific g globulins were purified and concentrated from the absorbed whole serum. These antibodies were fixed on staphylococcus cowan 1 NCTC-8325 whole-cells, using different chemical fixatives. It was observed that maximum fixation of g globulin to protein-A was achieved by 1-propanol 50% at 3 hours, which revealed through single radial immuno-diffusion techniqe. The rectal swab samples were cultured in an enrichment bile-peptons broth. After 5 hours 37°C while agitations, one drop of each sample was mixed with one drop of vibrio-cholerae bivalent mono-specific coagglutination reagent (VBCR. The results were read after 2 to 3 minutes. Finally though statistical analysis sensitivity and specificity of coagglutination test were calculated to be 95.1% and 99.2% respectively, when compared to positive & negative controls and conventional culture methods. Using VBCR, coagglutination test can be therefore considered as a simple, reliable and rapid method to detect V.cholerae O1 in the stool of patients in endemic area and less equipped laboratories

  9. In vivo localization of antibodies raised against Eimeria maxima wall forming bodies during sexual intracellular development. (United States)

    Frölich, Sonja; Shahparee, Annisha; Wasinger, Valerie C; Wallach, Michael


    SUMMARY Apicomplexan parasites cause devastating diseases in humans and livestock. Previously we demonstrated that antibodies targeting transmissible forms of the apicomplexan parasite, Eimeria, are effective at reducing parasite shedding thus preventing the transmission of the disease. However, the mechanisms responsible have not been fully defined. Moreover, there is no direct evidence that the parasite-specific IgG antibodies can reach the parasite developing in the enterocytes of the infected chicken host. This study summarizes our efforts using host immunity, parasite proteomics and 3D microscopy to provide a step forward in our understanding of how this immune response works. Eimeria maxima is an important pathogen of poultry and used as a surrogate for a number of human pathogens including Toxoplasma and Plasmodium. Our studies demonstrate that immunization with the purified wall forming bodies (WFBs) results in a production of parasite-specific IgG antibodies, which have the ability to reach in situ gametocytes in the intestinal lumen and permeate the enterocyte/parasite membranes in order to bind to the cytoplasmic Type 1 and Type 2 WFBs. This raises the intriguing possibility that via this process antibodies block the development of Eimeria maxima in vivo.

  10. Challenges to the development of vaccines to hepatitis C virus that elicit neutralizing antibodies.

    Directory of Open Access Journals (Sweden)

    Heidi Edelgard Drummer


    Full Text Available Despite 20 years of research, a vaccine to prevent hepatitis C virus (HCV infection has not been developed. A vaccine to prevent HCV will need to induce broadly reactive immunity able to prevent infection by the 7 genetically and antigenically distinct genotypes circulating world-wide. Hepatitis C virus encodes two surface exposed glycoproteins, E1 and E2 that function as a heterodimer to mediate viral entry. Neutralizing antibodies (NAbs to both E1 and E2 have been described with the major NAb target being E2. The function of E2 is to attach virions to host cells via cell surface receptors that include, but is not limited to, the tetraspanin CD81 and scavenger receptor B class I. However, E2 has developed a number of immune evasion strategies to limit the effectiveness of the NAb response and possibly limit the ability of the immune system to generate potent NAbs in natural infection. Hypervariable regions that shield the underlying core domain, subdominant neutralization epitopes and glycan shielding combine to make E2 a difficult target for the immune system. This review summarizes recent information on the role of neutralizing antibodies to prevent HCV infection, the targets of the neutralizing antibody response and structural information on glycoprotein E2 in complex with neutralizing antibodies. This new information should provide a framework for the rational design of new vaccine candidates that elicit highly potent broadly reactive NAbs to prevent HCV infection.

  11. Recombinant renewable polyclonal antibodies. (United States)

    Ferrara, Fortunato; D'Angelo, Sara; Gaiotto, Tiziano; Naranjo, Leslie; Tian, Hongzhao; Gräslund, Susanne; Dobrovetsky, Elena; Hraber, Peter; Lund-Johansen, Fridtjof; Saragozza, Silvia; Sblattero, Daniele; Kiss, Csaba; Bradbury, Andrew R M


    Only a small fraction of the antibodies in a traditional polyclonal antibody mixture recognize the target of interest, frequently resulting in undesirable polyreactivity. Here, we show that high-quality recombinant polyclonals, in which hundreds of different antibodies are all directed toward a target of interest, can be easily generated in vitro by combining phage and yeast display. We show that, unlike traditional polyclonals, which are limited resources, recombinant polyclonal antibodies can be amplified over one hundred million-fold without losing representation or functionality. Our protocol was tested on 9 different targets to demonstrate how the strategy allows the selective amplification of antibodies directed toward desirable target specific epitopes, such as those found in one protein but not a closely related one, and the elimination of antibodies recognizing common epitopes, without significant loss of diversity. These recombinant renewable polyclonal antibodies are usable in different assays, and can be generated in high throughput. This approach could potentially be used to develop highly specific recombinant renewable antibodies against all human gene products.

  12. Antibodies against human BLyS and APRIL attenuate EAE development in marmoset monkeys. (United States)

    Jagessar, S Anwar; Heijmans, Nicole; Oh, Luke; Bauer, Jan; Blezer, Erwin L A; Laman, Jon D; Migone, Thi-Sau; Devalaraja, Matt N; 't Hart, Bert A


    B lymphocyte stimulator (BLyS, also indicated as BAFF (B-cell activating factor) and CD257), and A Proliferation Inducing Ligand (APRIL, CD256) are two members of the TNF superfamily with a central role in B cell survival. Antibodies against these factors have potential therapeutic relevance in autoimmune inflammatory disorders with a proven pathogenic contribution of B cells, such as multiple sclerosis (MS). In the current study we performed a multi-parameter efficacy comparison of monoclonal antibodies against human anti-BLyS and anti-APRIL in a common marmoset (Callithrix jacchus) model of experimental autoimmune encephalomyelitis (EAE). A MS-like disease was induced by immunization with recombinant human myelin/oligodendrocyte glycoprotein (rhMOG) in complete Freund's adjuvant. The results show that the anti-BLyS and anti-APRIL antibody cause significant depletion of circulating CD20+ B cells, but a small subset of CD20 + CD40(high) B cells was not depleted. Induction of CD20+ B cell depletion from lymph nodes was only observed in the anti-BLyS treated monkeys. Both antibodies had a significant inhibitory effect on disease development, but all monkeys developed clinically evident EAE. Anti-BLyS treated monkeys were sacrificed with the same clinical signs as saline-treated monkeys, but nevertheless displayed significantly reduced spinal cord demyelination. This effect was not observed in the anti-APRIL treated monkeys. The two antibodies had a different effect on T cell subset activation and the profiles of ex vivo released cytokines. In conclusion, treatment with anti-BLyS and anti-APRIL delays the development of neurological disease in a relevant preclinical model of MS. The two mAbs achieve this effect via different mechanisms.

  13. Test-driven development with Mockito

    CERN Document Server

    Acharya, Sujoy


    This book is a hands-on guide, full of practical examples to illustrate the concepts of Test Driven Development.If you are a developer who wants to develop software following Test Driven Development using Mockito and leveraging various Mockito features, this book is ideal for you. You don't need prior knowledge of TDD, Mockito, or JUnit.It is ideal for developers, who have some experience in Java application development as well as a basic knowledge of unit testing, but it covers the basic fundamentals of TDD and JUnit testing to get you acquainted with these concepts before delving into them.

  14. Clinical factors associated with a Candida albicans Germ Tube Antibody positive test in Intensive Care Unit patients

    Directory of Open Access Journals (Sweden)

    Martín-Mazuelos Estrella


    Full Text Available Abstract Background Poor outcomes of invasive candidiasis (IC are associated with the difficulty in establishing the microbiological diagnosis at an early stage. New scores and laboratory tests have been developed in order to make an early therapeutic intervention in an attempt to reduce the high mortality associated with invasive fungal infections. Candida albicans IFA IgG has been recently commercialized for germ tube antibody detection (CAGTA. This test provides a rapid and simple diagnosis of IC (84.4% sensitivity and 94.7% specificity. The aim of this study is to identify the patients who could be benefited by the use of CAGTA test in critical care setting. Methods A prospective, cohort, observational multicentre study was carried out in six medical/surgical Intensive care units (ICU of tertiary-care Spanish hospitals. Candida albicans Germ Tube Antibody test was performed twice a week if predetermined risk factors were present, and serologically demonstrated candidiasis was considered if the testing serum dilution was ≥ 1:160 in at least one sample and no other microbiological evidence of invasive candidiasis was found. Results Fifty-three critically ill non-neutropenic patients (37.7% post surgery were included. Twenty-two patients (41.5% had CAGTA-positive results, none of them with positive blood culture for Candida. Neither corrected colonization index nor antifungal treatment had influence on CAGTA results. This finding could corroborate that the CAGTA may be an important biomarker to distinguish between colonization and infection in these patients. The presence of acute renal failure at the beginning of the study was more frequent in CAGTA-negative patients. Previous surgery was statistically more frequent in CAGTA-positive patients. Conclusions This study identified previous surgery as the principal clinical factor associated with CAGTA-positive results and emphasises the utility of this promising technique, which was not

  15. Development of antibody-based c-Met inhibitors for targeted cancer therapy

    Directory of Open Access Journals (Sweden)

    Lee D


    Full Text Available Dongheon Lee, Eun-Sil Sung, Jin-Hyung Ahn, Sungwon An, Jiwon Huh, Weon-Kyoo You Hanwha Chemical R&D Center, Biologics Business Unit, Daejeon, Republic of Korea Abstract: Signaling pathways mediated by receptor tyrosine kinases (RTKs and their ligands play important roles in the development and progression of human cancers, which makes RTK-mediated signaling pathways promising therapeutic targets in the treatment of cancer. Compared with small-molecule compounds, antibody-based therapeutics can more specifically recognize and bind to ligands and RTKs. Several antibody inhibitors of RTK-mediated signaling pathways, such as human epidermal growth factor receptor 2, vascular endothelial growth factor, epidermal growth factor receptor or vascular endothelial growth factor receptor 2, have been developed and are widely used to treat cancer patients. However, since the therapeutic options are still limited in terms of therapeutic efficacy and types of cancers that can be treated, efforts are being made to identify and evaluate novel RTK-mediated signaling pathways as targets for more efficacious cancer treatment. The hepatocyte growth factor/c-Met signaling pathway has come into the spotlight as a promising target for development of potent cancer therapeutic agents. Multiple antibody-based therapeutics targeting hepatocyte growth factor or c-Met are currently in preclinical or clinical development. This review focuses on the development of inhibitors of the hepatocyte growth factor/c-Met signaling pathway for cancer treatment, including critical issues in clinical development and future perspectives for antibody-based therapeutics. Keywords: hepatocyte growth factor, ligands, receptor tyrosine kinase, signaling pathway, therapeutic agent

  16. Engineered Bovine Antibodies in the Development of Novel Therapeutics, Immunomodulators and Vaccines

    Directory of Open Access Journals (Sweden)

    Madhuri Koti


    Full Text Available Some bovine antibodies across all classes are unique, such as the CDR3 of the variable heavy-domain (VH CDR3, which is exceptionally long (up to 66 amino acids, unlike most conventional antibodies where the VH CDR3 loops range from 10 to 25 amino acids. The exceptionally long VH CDR3 is encoded by unusually long germline IGHD genes together with insertion of novel “a” nucleotide rich conserved short nucleotide sequence (CSNS specifically at the IGH V-D junction. Such an exceptionally long VH CDR3 confers unique “knob and stalk” structural architecture where the knob, formed by intra-VH CDR3 disulfide bridges, is separated by 20 Å solvent exposed stalk composed of anti-parallel beta strands. The substitution of the knob with cytokines, such as, erythropoietin and granulocyte colony stimulating factor 3 (granulocyte colony stimulating factor, results in expression of functional fusion proteins with enhanced pharmacokinetics. The beta stranded stalk can be substituted with other rigid structures, for example, repeat alpha helices to form coiled-coil that mimics the beta-stranded stalk and, thus, opens opportunities for insertion of this structure in the CDRs of antibodies across species. Given the versatility of such a structural platform in bovine antibody VH CDR3, it provides the opportunity for the development of new generation of diagnostics, therapeutics, vaccines and immunomodulating drugs.

  17. Development and evaluation of a latex agglutination test for the rapid serodiagnosis of tularemia. (United States)

    Rastawicki, Waldemar; Rokosz-Chudziak, Natalia; Chróst, Anna; Gierczyński, Rafał


    A latex agglutination test (LAT) was developed for a rapid detection of antibodies against Francisella tularensis. The assay is performed by mixing serum with antigen-coated latex beads and read within 5 min. Developed LAT has been proved to be a specific, sensitive, fast, easy-to-perform and cost-efficient tool for the routine diagnosis of tularemia.

  18. Test Marketing in New Product Development (United States)

    Klompmaker, Jay E.; And Others


    Discusses the role of test marketing in new product development, based on interviews with marketing executives. Attempts to clarify when a test market should be done, what its aims should be, and how it should be used. (JG)

  19. An experimental test of stroke recovery by implanting a hyaluronic acid hydrogel carrying a Nogo receptor antibody in a rat model

    Energy Technology Data Exchange (ETDEWEB)

    Ma Jun [Biomaterials Laboratory, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Tian Weiming [Biomaterials Laboratory, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Hou Shaoping [Beijing Institute of Neuroscience, Capital University of Medical Sciences, Beijing 100054 (China); Xu Qunyuan [Beijing Institute of Neuroscience, Capital University of Medical Sciences, Beijing 100054 (China); Spector, Myron [Tissue Engineering, VA Boston Healthcare System, Harvard Medical School, Boston, MA (United States); Cui Fuzhai [Biomaterials Laboratory, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)


    The objective of the study was to determine the effects of a hyaluronic-acid-based (HA-based) hydrogel implant, carrying a polyclonal antibody to the Nogo-66 receptor (NgR), on adult rats that underwent middle cerebral artery occlusion (MCAO). Behavioral tests of a forelimb-reaching task suggested that the disabled function of the impaired forelimb in this stroke model was ameliorated by the implant to a certain extent. These behavioral findings were correlated with immunohistochemical results of investigating the distribution of NgR antibody, neurofilaments (NF) and neuron-specific class III {beta}-tubulin (TuJ1) in the brain sections. The porous hydrogel functioned as a scaffold to deliver the NgR antibody, support cell migration and development. In addition, it was found NF-positive and TuJ1-positive expressions were distributed in the implanted hydrogel. Collectively, the results demonstrate the promise of the HA hydrogel as a scaffold material and the delivery vehicle of the NgR antibody for the repair of defects and the support of neural regeneration in the brain.

  20. Development of an ELISA kit using monoclonal antibody to Clostridium difficile toxin A

    Institute of Scientific and Technical Information of China (English)

    Si-Wu Fu; Ya-Li Zhang; Dian-Yuan Zhou


    AIM: To establish an ELISA kit using monoclonal antibodiesagainst Clostridium difficile ( C. difficile) toxin A.METHODS: An indirect sandwich ElISA was described using the purified rabbit monospecific antiserum as capturing antibody. After the polystyrene microtitre plates with 96 fiat-bottomed wells were coated with rabbit antiserum, the wells were blocked with 100 g/L BSA in PBS-T. C. difficiletoxin A or culture filtrates were added to each well and then monoclonal antibodies IgG-horseradish peroxidase conjugate was added as detecting antibody, tetramethylbenzidine was used as substrate and A450 of the stopped reacting product was recorded in an automated plate reader. RESULTS: The tested specimens included culture filtrates of 2 strains of toxigenic C. difficile, 2 strains of non-toxigenic C. difficile, 26 strains of E. coli, 2 strains of S. dysenteriae, 1 strain of Bif infantis, 5 strains of V. cholera, 2 strains ofS. typhi, 7 strains of C. botulinum, 1 strain of toxigenic C. sordllii, and 1 strain of C. butyricum. A total of 47 strains of culture filtrates were all negative except for 2 strains of toxigenic C. difficile. The detective limitation of toxin A was 0.1 ng/mL.CONCLUSION: An ELISA kit with high specificity and excellent sensitivity for the rapid detection of C. difficile toxin A was established. It will be a useful tool for diagnostic test of C. difficile toxin A.

  1. Rotary Engine Friction Test Rig Development Report (United States)


    5  4.  Friction Rig Development 7  5.  AutoCAD ...Figure 4. Engine friction test rig AutoCAD model. ........................................................................8  Figure 5. dead center. 8 5. AutoCAD Model Development A model of the rotary engine friction test rig was developed to determine the optimal

  2. Development of an alternative method for testing the immunogenicity of diphtheria vaccines. (United States)

    Manghi, M A; Pasetti, M F; Brero, M L; Deluchi, S; di Paola, G; Mathet, V; Eriksson, P V


    The immunogenicity of the diphtheria component of 73 commercial vaccines from five different manufacturers was tested by the toxin neutralization test (TNT) and the enzyme-linked immunosorbent assay (ELISA) developed in our laboratory. A comparison of the antibody levels measured by both assays showed a very good correlation (r = 0.95, p antibody levels as low as 5.5 x 10(-5) IU ml-1. To evaluate the possibility of accelerating the active immunization during the activity test of vaccines, an alternative schedule using one single human dose was assayed. A very good correlation was observed between the IgG antibody response obtained with this schedule and with the traditional programme. Therefore, the cost and the time required to perform the activity test may be considerably reduced when both the rapid immunization schedule and the ELISA are used.

  3. Human Ig knockin mice to study the development and regulation of HIV-1 broadly neutralizing antibodies. (United States)

    Verkoczy, Laurent; Alt, Frederick W; Tian, Ming


    A major challenge for HIV-1 vaccine research is developing a successful immunization approach for inducing broadly neutralizing antibodies (bnAbs). A key shortcoming in meeting this challenge has been the lack of animal models capable of identifying impediments limiting bnAb induction and ranking vaccine strategies for their ability to promote bnAb development. Since 2010, immunoglobulin knockin (KI) technology, involving inserting functional rearranged human variable exons into the mouse IgH and IgL loci has been used to express bnAbs in mice. This approach has allowed immune tolerance mechanisms limiting bnAb production to be elucidated and strategies to overcome such limitations to be evaluated. From these studies, along with the wealth of knowledge afforded by analyses of recombinant Ig-based bnAb structures, it became apparent that key functional features of bnAbs often are problematic for their elicitation in mice by classic vaccine paradigms, necessitating more iterative testing of new vaccine concepts. In this regard, bnAb KI models expressing deduced precursor V(D)J rearrangements of mature bnAbs or unrearranged germline V, D, J segments (that can be assembled into variable region exons that encode bnAb precursors), have been engineered to evaluate novel immunogens/regimens for effectiveness in driving bnAb responses. One promising approach emerging from such studies is the ability of sequentially administered, modified immunogens (designed to bind progressively more mature bnAb precursors) to initiate affinity maturation. Here, we review insights gained from bnAb KI studies regarding the regulation and induction of bnAbs, and discuss new Ig KI methodologies to manipulate the production and/or expression of bnAbs in vivo, to further facilitate vaccine-guided bnAb induction studies.

  4. Development of an Enzyme-Linked Immunosorbent Assay Based on Fusion VP2332-452 Antigen for Detecting Antibodies against Aleutian Mink Disease Virus. (United States)

    Chen, Xiaowei; Song, Cailing; Liu, Yun; Qu, Liandong; Liu, Dafei; Zhang, Yun; Liu, Ming


    For detection of Aleutian mink disease virus (AMDV) antibodies, an enzyme-linked immunosorbent assay (ELISA) was developed using the recombinant VP2332-452 protein as an antigen. Counterimmunoelectrophoresis (CIEP) was used as a reference test to compare the results of the ELISA and Western blotting (WB); the specificity and sensitivity of the VP2332-452 ELISA were 97.9% and 97.3%, respectively, which were higher than those of WB. Therefore, this VP2332-452 ELISA may be a preferable method for detecting antibodies against AMDV.

  5. Evaluation of Anti-Nuclear antibody test results in clinical practice

    Directory of Open Access Journals (Sweden)

    Nevreste Çelikbilek


    Full Text Available Objective: Aim of this study is to evaluate anti-nuclear antibody (ANA test results obtained between 2009 and 2011. Methods: Of a totally 5068 cases tested for ANA by indirect immunofluorescence method (IIFA, randomly chosen 982 ANA-positive cases were reviewed in terms of gender, level and pattern of fluorescence, anti-dsDNA (anti-double stranded DNA and anti-extractable nuclear antigen (ENA profile. Anti-dsDNA levels and anti-ENA profiles were determined by enzyme linked immune assay (ELISA and immune-blotting (IB, respectively. Results: Sex distribution of ANA positive patients was determined as 756 (77% females and 226 (23% males. Fifty per cent of the cases were from rheumatology department, 20% from gastroenterology and 30% from other units. Fluorescence levels were considered borderline or weak positive in 62.6% of the samples. The most frequent patterns were homogeneous (23%, speckled (22%, homogeneous-speckled (15.5% and nucleolar (13.5%. Anti-dsDNA were studied in 759 ANA positive patients and 66 (8.7% samples were found positive, being 44 of them (68.8% with homogeneous pattern and the rest with speckled, nucleolar, nuclear dots, centromeric or midbody patterns. Totally 131 (31.6% of 414 samples studied for anti-ENA profile were found positive. The first four frequent profiles were SSA (34.4%, SSA-SSB (16.8%, Scl70 (16% and Sm/RNP (9.2%. Conclusion: Our results are similar with the current related literature. It is known that autoantibodies can be detectable before clinical symptoms being apparent, especially in SLE. Therefore, borderline or weak fluorescence levels should also be reported and the patients having them should be followed-up carefully. J Microbiol Infect Dis 2015;5(2: 63-68

  6. Hypersonic Flight Test Windows for Technology Development Testing (United States)


    hypersonic vehicles requires the application of a significant amount of thermal protection or use of a hot structures concept, which can be a major cost...AFRL-RQ-WP-TM-2013-0260 HYPERSONIC FLIGHT TEST WINDOWS FOR TECHNOLOGY DEVELOPMENT TESTING Barry M. Hellman Vehicle Technology Branch...DATES COVERED (From - To) November 2013 Final 01 November 2013 – 25 November 2013 4. TITLE AND SUBTITLE HYPERSONIC FLIGHT TEST WINDOWS FOR

  7. Testing Infrastructure for Operating System Kernel Development

    DEFF Research Database (Denmark)

    Walter, Maxwell; Karlsson, Sven


    Testing is an important part of system development, and to test effectively we require knowledge of the internal state of the system under test. Testing an operating system kernel is a challenge as it is the operating system that typically provides access to this internal state information. Multi......-core kernels pose an even greater challenge due to concurrency and their shared kernel state. In this paper, we present a testing framework that addresses these challenges by running the operating system in a virtual machine, and using virtual machine introspection to both communicate with the kernel...... and obtain information about the system. We have also developed an in-kernel testing API that we can use to develop a suite of unit tests in the kernel. We are using our framework for for the development of our own multi-core research kernel....


    Energy Technology Data Exchange (ETDEWEB)



    This Test Plan describes the testing and chemical analyses release rate studies on tank residual samples collected following the retrieval of waste from the tank. This work will provide the data required to develop a contaminant release model for the tank residuals from both sludge and salt cake single-shell tanks. The data are intended for use in the long-term performance assessment and conceptual model development.

  9. AngularJS test-driven development

    CERN Document Server

    Chaplin, Tim


    This book is for developers who want to learn about AngularJS development by applying testing techniques. You are assumed to have a basic knowledge and understanding of HTML, JavaScript, and AngularJS.

  10. The enzyme-linked immunosorbent assay (ELISA) as a serological test for detecting antibodies against Leptospira interrogans serovar hardjo in sheep. (United States)

    Adler, B; Faine, S; Gordon, L M


    The enzyme-liked immunosorbent assay (ELISA) was compared with the standard microscopic agglutination test (MAT) as a method for detecting antibodies against Leptospira interrogans serovar hardjo in sheep. Peak antibody levels detected by the 2 tests occurred at different times following experimental infection of sheep. In serums from flocks of sheep with naturally acquired infection there was a 95% correlation between MAT and ELISA with respect to the presence or absence of antibody to serovar hardjo, although the levels of correlation of the titres of the 2 tests was low. The 2 tests appeared to measure different antigen-antibody systems. The ELISA would be a useful test for screening large numbers of serums for antibodies to L. interrogans serovar hardjo.

  11. Evaluation of a direct immunofluorescent antibody (difma test using Leishmania genus - specific monoclonal antibody in the routine diagnosis of cutaneous leishmaniasis

    Directory of Open Access Journals (Sweden)

    Martha E. Chico


    Full Text Available A direct immunofluorescent antibody (DIFMA test using a Leishmania genus- specific monoclonal antibody was evaluated in the routine diagnosis of cutaneous leishmaniasis (CL in Ecuador. This test was compared with the standard diagnostic techniques of scrapings, culture and histology. Diagnostic samples were taken from a total of 90 active dermal ulcers from patients from areas of Ecuador known to be endemic for cutaneous leishmaniasis. DIFMA was positive in all lesions. It was shown to be significantly superior to standard diagnostic methods either alone or in combination. The sensitivity of DIFMA did not diminish with chronicity of lesions. This test proved to be extremely useful in the routine diagnosis of CL because it is highly sensitive, is easy to use and produces rapid results.O método de imunofluorescência direta (DIFMA, com anticorpos monoclonais gênero- específicos para Leishmania, foi avaliado na rotina diagnostica da leishmaniose cutânea no Equador. O método foi comparado com técnicas diagnosticas de rotina: o esfregaço, a cultura e o exame histopatolôgico. As amostras para o diagnóstico foram obtidas de um total de 90 lesões cutâneas ativas, de doentes das ãreas do Equador, endêmicas para leishmaniose cutânea. O DIFMA foi positivo em todas as lesões, com resultados significativamente superior aos métodos diagnósticos de rotina, isolado ou em combinação. A sensibilidade do DFIMA não diminui em lesões crônicas. O método mostra-se muito útil no diagnóstico de leishmaniose cutânea, pela sua sensibilidade, rapidez e facilidade de execução.

  12. Significance of serum antibody test for toxocariasis in healthy healthcare examinees with eosinophilia in Seoul and Gyeongsangnam-do, Korea. (United States)

    Kim, Hong Seok; Jin, Yan; Choi, Min-Ho; Kim, Jae-Hwan; Lee, Young Ha; Yoon, Cheong Ha; Hwang, Eui-Hyuk; Kang, Hun; Ahn, Sang-Yong; Kim, Gi Jin; Hong, Sung-Tae


    There have been numerous reports on the relationship between eosinophilia and toxocariasis. The present study investigated seropositive rates of toxocariasis among healthy people with or without eosinophilia in urban and rural areas, and assessed risk factors for positive antibody test. A total of 610 healthy people, who visited health check-up (Medicheck®, Korea Association of Health Promotion), 310 from Seoul and 300 from Gyeongsangnam-do, were subjected for this study. Their serum samples were tested by ELISA with the crude antigen of Toxocara canis larvae. Cross-reactions with other tissue invading helminth antigens were also investigated. Total antibody positive rate of toxocariasis was 8.7% of the 610 subjects. When the subjects were grouped into 3 by their eosinophil counts, the antibody positive rates significantly differed by the groups; 5.9% (18/306) in the group500/µL (P=0.028). A total of 22 serum samples cross-reacted with other tissue-invading helminth antigens. A questionnaire analysis recognized drinking alcohol and smoking as significant risk factors of toxocariasis. In conclusion, toxocariasis antibody positive rate is correlated with eosinophil counts. It is recommended that healthy subjects with eosinophilia by routine health examination and risk factors undergo Toxocara serology by multiantigen ELISA to investigate etiology.

  13. Development of a bispecific monoclonal antibody to pesticide carbofuran and triazophos using hybrid hybridomas. (United States)

    Jin, R Y; Guo, Y R; Wang, C M; Wu, J X; Zhu, G N


    A mouse hybrid hybridoma (tetradoma) was derived from fusing hybridomas producing monoclonal antibody to N-methylcarbamate pesticide carbofuran with hybridomas producing monoclonal antibody to organophosphorus pesticide Triazophos. The prepared tetradoma line (12C1 to 2H12) secreted hybrid immunoglobulin exhibiting parental and bispecific binding characteristics. The effect of relevant physicochemical factors on the immunoassay based on the 12C1 to 2H12 bispecific monoclonal antibody had been studied to optimize the ELISA performance. The developed immunoassay showed that the detection limit (I(20)) were 0.36 and 1.89 ng/mL for triazophos and carbofuran, respectively, without obvious cross-reactivity to other related compounds. Water samples spiked with triazophos at 0.5, 1, and 5 ng/mL or carbofuran at 5, 10, and 20 ng/mL were directly analyzed by the developed ELISA format. The mean recovery of triazophos and carbofuran were 108.1% and 107.5%, with variation coefficient of 15.9% and 17.7%, respectively.

  14. Post-transplant development of C1q-positive HLA antibodies and kidney graft survival. (United States)

    Piazza, Antonina; Poggi, Elvira; Ozzella, Giuseppina; Adorno, Domenico


    The development of de novo human leukocyte antigen (HLA) donor specific antibodies (DSA), detected by both cytotoxic or solid phase assays, was considered the major risk factor for allograft failure in kidney transplantation. However, it was shown that not all patients with persistent production of DSA suffered loss of their grafts. Modified Luminex-Single Antigen assays, able to identify C1q-fixing antibodies, represent a new strategy in assessing the clinical relevance of detected DSA. This study demonstrated that C1q-fixing capability of de novo DSA is a clinically relevant marker of worse outcome and inferior graft survival in kidney transplantation. In fact, our findings evidenced a very low graft survival only in the patients who developed DSA able to fix C1q during post-transplant course, while patients producing C1q-negative DSA had good graft survival, which was comparable to that found in our previous study for DSA-negative patients. Moreover, anti-HLA class II antibodies had a higher incidence than anti-HLA class I, and the ability to fix C1q was significantly more frequent among anti-DQ DSA than anti-DR DSA. Monitoring of de novo C1q-DSA production represents a useful, non-invasive tool for risk stratification and prediction of graft outcome in kidney transplantation.

  15. Integrated Language Definition Testing: Enabling Test-Driven Language Development

    NARCIS (Netherlands)

    Kats, L.C.L.; Vermaas, R.; Visser, E.


    The reliability of compilers, interpreters, and development environments for programming languages is essential for effective software development and maintenance. They are often tested only as an afterthought. Languages with a smaller scope, such as domain-specific languages, often remain untested.

  16. Test Development Study On The Spatial Visualization

    Directory of Open Access Journals (Sweden)



    Full Text Available Spatial visualization, frequently used in many stages of daily life, is also an indispensable part of mathematics and geometry courses. There are many definitions of spatial visualization ability and various tests have been developed to measure this ability. The aim of this study is to develop a new test for determining the spatial visualization ability for students in higher education. For this purpose, a test including 29 items was prepared. The developed test’s pilot scheme was applied to 236 students of mathematics and mathematics education programs in different two state universities. The data obtained were analyzed by packaged software like Iteman 4, SPSS 17.0 and Lisrel8.7. The test, which was developed by discarding two items according to results of item analysis, validity and reliability analysis and confirmatory factor analysis, was finalized. The Cronbach α coefficient of test was calculated as .84 and RMSEA value of test was calculated as 0,032.

  17. Antibody screening tests variably overestimate the prevalence of hepatitis C virus infection among HIV-infected adults in Ghana. (United States)

    King, S; Adjei-Asante, K; Appiah, L; Adinku, D; Beloukas, A; Atkins, M; Sarfo, S F; Chadwick, D; Phillips, R O; Geretti, A M


    HIV coinfection with HCV has been poorly studied in sub-Saharan Africa, and the reliability of available seroprevalence estimates remains uncertain. The study aim was to determine HCV RNA prevalence in HIV-infected subjects receiving care in Kumasi, Ghana, and relate the findings to HCV antibody detection. From a population of 1520 HIV-infected adults, all HBsAg-positive subjects (n = 236) and a random subset of HBsAg-negative subject (n = 172) were screened for HCV RNA using pooled plasma; positive samples were genotyped by core and NS5B sequencing. HCV antibodies were detected by three commercial screening assays and confirmed by the line immunoassay. HCV RNA was detected in 4/408 subjects (1.0%, 95% confidence interval 0.0-1.9%), comprising 3/236 (1.3%; 0.0-2.8%) HBsAg-positive and 1/172 (0.6%; 0.0-1.8%) HBsAg-negative subjects. HCV RNA-positive subjects showed reactivity in all three antibody screening assays. Among HCV RNA-negative subjects, 5/67 (7.5%), 5/67 (7.5%) and 19/67 (28.4%) showed antibody reactivity by each screening assay, respectively, including two (3.0%) with reactivity by all three assays. Only one sample (1.5%) had confirmed antibody reactivity by line immunoassay indicating past HCV infection. HCV-positive subjects (three males, two females) were aged 30-46 years, by questionnaire-based interview reported surgical procedures and blood transfusion as risk factors for infection. HCV genotypes were 2 (subtypes 2j, 2l, 2k/unassigned) and 1 (subtype unassigned). Without further testing, HCV antibody screening assays variably overestimated HCV prevalence among HIV-infected subjects in Ghana. These findings inform the interpretation of previous seroprevalence estimates based upon screening assays alone.

  18. Automated Vision Test Development and Validation (United States)


    AFRL-SA-WP-SR-2016-0020 Automated Vision Test Development and Validation Steve Wright, Darrell Rousse, Alex van Atta...Special Report 3. DATES COVERED (From – To) April 2014 – April 2015 4. TITLE AND SUBTITLE Automated Vision Test Development and Validation 5a...23 Nov 2016. 14. ABSTRACT The Optec Vision Test , originally produced in 1951 as the Armed Forces Vision Tester, is the sole device used to qualify

  19. Waiving in vivo studies for monoclonal antibody biosimilar development: National and global challenges. (United States)

    Chapman, Kathryn; Adjei, Akosua; Baldrick, Paul; da Silva, Antonio; De Smet, Karen; DiCicco, Richard; Hong, Seung Suh; Jones, David; Leach, Michael W; McBlane, James; Ragan, Ian; Reddy, Praveen; Stewart, Donald I H; Suitters, Amanda; Sims, Jennifer


    Biosimilars are biological medicinal products that contain a version of the active substance of an already authorised original biological medicinal product (the innovator or reference product). The first approved biosimilar medicines were small proteins, and more recently biosimilar versions of innovator monoclonal antibody (mAb) drugs have entered development as patents on these more complex proteins expire. In September 2013, the first biosimilar mAb, infliximab, was authorised in Europe. In March 2015, the first biosimilar (Zarxio™, filgrastim-sndz, Sandoz) was approved by the US Food and Drug Administration; however, to date no mAb biosimilars have been approved in the US. There are currently major differences between how biosimilars are regulated in different parts of the world, leading to substantial variability in the amount of in vivo nonclinical toxicity testing required to support clinical development and marketing of biosimilars. There are approximately 30 national and international guidelines on biosimilar development and this number is growing. The European Union's guidance describes an approach that enables biosimilars to enter clinical trials based on robust in vitro data alone; in contrast, the World Health Organization's guidance is interpreted globally to mean in vivo toxicity studies are mandatory. We reviewed our own experience working in the global regulatory environment, surveyed current practice, determined drivers for nonclinical in vivo studies with biosimilar mAbs and shared data on practice and study design for 25 marketed and as yet unmarketed biosimilar mAbs that have been in development in the past 5y. These data showed a variety of nonclinical in vivo approaches, and also demonstrated the practical challenges faced in obtaining regulatory approval for clinical trials based on in vitro data alone. The majority of reasons for carrying out nonclinical in vivo studies were not based on scientific rationale, and therefore the authors

  20. Detection of antibodies against H5 and H7 strains in birds: evaluation of influenza pseudovirus particle neutralization tests

    Directory of Open Access Journals (Sweden)

    Sofie Wallerström


    Full Text Available Introduction: Avian influenza viruses circulate in bird populations, and it is important to maintain and uphold our knowledge of the viral strains that are currently of interest in this context. Here, we describe the use of hemagglutinin-pseudotype retroviruses based on highly pathogenic influenza viruses for the screening of avian sera for influenza A antibodies. Our aim was also to determine whether the pseudovirus neutralization tests that we assessed were sensitive and simple to use compared to the traditional methods, including hemagglutination inhibition assays and microneutralization tests. Material and methods: H5 and H7 pseudovirus neutralization tests were evaluated by using serum from infected rabbits. Subsequently, the assays were further investigated using a panel of serum samples from avian species. The panel contained samples that were seropositive for five different hemagglutinin subtypes as well as influenza A seronegative samples. Results and discussion: The results suggest that the pseudovirus neutralization test is an alternative to hemagglutination inhibition assays, as we observed comparable titers to those of both standard microneutralizations assays as well as hemagglutinin inhibition assays. When evaluated by a panel of avian sera, the method also showed its capability to recognize antibodies directed toward low-pathogenic H5 and H7. Hence, we conclude that it is possible to use pseudoviruses based on highly pathogenic avian influenza viruses to screen avian sera for antibodies directed against influenza A subtypes H5 and H7.

  1. Clinical and anti-HLA antibody profile of nine renal transplant recipients with failed grafts: donor-specific and non-donor-specific antibody development. (United States)

    Rebellato, Lorita M; Ozawa, Miyuki; Verbanac, Kathryn M; Catrou, Paul; Haisch, Carl E; Terasaki, Paul I


    This study applied the single antigen microsphere technology to the retrospective analysis of sequential post-transplant serum samples in the context of the patient's clinical course. Detailed information on nine of the study patients was presented as representative of the larger cohort and illustrative of different patterns of anti-HLA antibody development and different clinical scenarios that culminated in graft failure. Our major observations are summarized as follows: 1. These data confirm the high sensitivity of the single antigen bead method: In some patients, DSA and NDSA that were undetected by standard methods were found pre-transplant and in sequential post-transplant samples. 2. The precise role that anti-HLA antibody plays in a particular rejection are complicated in cases in which humoral rejection is not diagnosed in the biopsy: The possible involvement of ADCC and mechanisms involving an indirect role for antibody in the rejection process should be carefully investigated. 3. Although anti-HLA antibodies are associated with graft rejection, the time interval between detection and rejection can vary dramatically between patients. Both DSA and NDSA can be adsorbed by the graft and erratically detected in the circulation, in some cases remaining undetected until nephrectomy. 4. Anti-HLA antibody strengths often fluctuate widely over a patient's clinical course, with de novo DSA generally of greater strength than de novo NDSA. 5. In addition to DSA, we have observed the consistent induction of diverse, cross-reactive NDSA. This occurs not only during the post-transplant course but also after graft failure, when immunosuppression is tapered prior to nephrectomy. Our data support further studies to evaluate the value of prospective monitoring of anti-HLA antibodies to better understand the place of anti-HLA antibodies in acute rejection. This may improve our ability to reverse some acute rejection episodes. Since acute rejection has been considered a

  2. Detection of Schistosoma mansoni Antibodies in a Low-Endemicity Area Using Indirect Immunofluorescence and Circumoval Precipitin Test (United States)

    Carvalho do Espírito-Santo, Maria Cristina; Pinto, Pedro Luiz; Gargioni, Cybele; Viviana Alvarado-Mora, Monica; Pagliusi Castilho, Vera Lúcia; Pinho, João Ranato Rebello; de Albuquerque Luna, Expedito José; Borges Gryschek, Ronaldo Cesar


    Parasitological diagnostic methods for schistosomiasis lack sensitivity, especially in regions of low endemicity. The objective of this study was to determine the prevalence of Schistosoma mansoni infections by antibody detection using the indirect immunofluorescence assay (IFA-IgM) and circumoval precipitin test (COPT). Serum samples of 572 individuals were randomly selected. The IFA-IgM and COPT were used to detect anti-S. mansoni antibodies. Of the patients studied, 15.9% (N = 91) were IFA-IgM positive and 5.1% (N = 29) had COPT reactions (P < 0.001 by McNemar's test). Immunodiagnostic techniques showed higher infection prevalence than had been previously estimated. This study suggests that combined use of these diagnostic tools could be useful for the diagnosis of schistosomiasis in epidemiological studies in areas of low endemicity. PMID:24639303

  3. Protective levels of canine distemper virus antibody in an urban dog population using plaque reduction neutralization test

    Directory of Open Access Journals (Sweden)

    O.I. Oyedele


    Full Text Available Blood samples from 50 dogs were collected at three veterinary clinics in Ibadan and Abuja, Nigeria and the serum from each sample was evaluated serologically for neutralizing antibodies against canine distemper virus (CDV by the highly sensitive plaque reduction (PRN neutralization assay. Thirteen dogs had plaque reduction neutralization titres of 0-100, seven had titres of 100-1 000 while 30 had titres ranging from 1 000-6 000. The PRN titres of vaccinated dogs were found to be significantly higher than unvaccinated dogs. The widespread use of the highly reproducible PRN test for the evaluation of antibody response to CDV may be very important in the generation of international CDV positive serum standards that should help to improve pre-and post-vaccination testing of dogs worldwide.

  4. An indirect immunofluorescence antibody test employing whole eggs as the antigen for the diagnosis of abdominal angiostrongyliasis

    Directory of Open Access Journals (Sweden)

    Elizabeth Abrahams-Sandi


    Full Text Available Abdominal angiostrongyliasis is a potentially fatal zoonotic disease with a broad geographical distribution throughout Central and South America. This study assessed the performance of Angiostrongylus costaricensis eggs as the antigen in an indirect immunofluorescence assay for the determination of parasite-specific IgG and IgG1 antibodies. For prevalence studies, an IgG antibody titre > 16 was identified as the diagnostic threshold with the best performance, providing 93.7% sensitivity and 84.6% specificity. Cross reactivity was evaluated with 65 additional samples from patients with other known parasitic infections. Cross reactivity was observed only in samples from individuals infected with Strongyloides stercoralis. For clinical diagnosis, we recommend the determination of IgG only as a screening test. IgG1 determination may be used to increase the specificity of the results for patients with a positive screening test.

  5. A rapid latex agglutination test for the detection of anti-cysticercus antibodies in cerebrospinal fluid (CSF

    Directory of Open Access Journals (Sweden)

    ROCHA Sérgio M.


    Full Text Available Simple and rapid latex-based diagnostic tests have been used for detecting specific antigens or antibodies in several diseases. In this article, we present the preliminary results obtained with a latex agglutination test (LAT for diagnosing neurocysticercosis by detection of antibodies in CSF. A total of 43 CSF samples were assayed by the LAT: 19 CSF samples from patients with neurocysticercosis and 24 CSF samples from patients with other neurologic disorders (neurosyphilis, n = 8; neurotoxoplasmosis, n = 3; viral meningitis, n = 4, chronic headache, n = 9. The LAT exhibited 89.5% sensitivity and 75% specificity. The use of LAT seems to be an additional approach for the screening of neurocysticercosis with advantage of simplicity and rapidity. Further studies could be performed using purified antigens and serum samples.

  6. Development of Immunoassay Based on Monoclonal Antibody Reacted with the Neonicotinoid Insecticides Clothianidin and Dinotefuran

    Directory of Open Access Journals (Sweden)

    Seiji Iwasa


    Full Text Available Enzyme-linked immunosorbent assay (ELISA based on a monoclonal antibody (MoAb was developed for the neonicotinoid insecticide clothianidin. A new clothianidin hapten (3-[5-(3-methyl-2-nitroguanidinomethyl-1,3-thiazol-2-ylthio] propionic acid was synthesized and conjugated to keyhole limpet hemocyanin, and was used for monoclonal antibody preparation. The resulting MoAb CTN-16A3-13 was characterized by a direct competitive ELISA (dc-ELISA. The 50% of inhibition concentration value with clothianidin was 4.4 ng/mL, and the working range was 1.5–15 ng/mL. The antibody showed high cross-reactivity (64% to dinotefuran among the structurally related neonicotinoid insecticides. The recovery examinations of clothianidin for cucumber, tomato and apple showed highly agreement with the spiked concentrations; the recovery rate was between 104% and 124% and the coefficient of variation value was between 1.8% and 15%. Although the recovery rate of the dc-ELISA was slightly higher than that of HPLC analysis, the difference was small enough to accept the dc-ELISA as a useful method for residue analysis of clothianidin in garden crops.

  7. Lyme disease antibody (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 . ...

  8. Test and Behaviour Driven Development with Python

    CERN Document Server

    CERN. Geneva


    Experience has taught us that bugs are impossible to avoid when programming. Specially on continuous delivery processes where there are new versions that refactor or incorporate new modules to the project. Although, there are different tools which help us to ensure code quality by enabling developers to catch bugs while still in the development stage. In this talk, I will talk about Test-driven development(TDD) and Behaviour-Driven development (BDD) methodologies focused on web development. Also, I will present an overview of unit testing tools as Selenium or Behave, which help us to produce working software, with fewer bugs, quickly and consistently.

  9. Western blotting using Strongyloides ratti antigen for the detection of IgG antibodies as confirmatory test in human strongyloidiasis

    Directory of Open Access Journals (Sweden)

    Luciana Pereira Silva


    Full Text Available The present study was conducted to evaluate the frequency of antigenic components recognized by serum IgG antibodies in Western blotting (WB using a Strongyloides ratti larval extract for the diagnosis of human strongyloidiasis. In addition, the WB results were compared to the enzyme-linked immunosorbent assay (ELISA and the indirect immunofluorescence antibody test (IFAT results. Serum samples of 180 individuals were analyzed (80 with strongyloidiasis, 60 with other intestinal parasitoses, and 40 healthy individuals. S. ratti was obtained from fecal culture of experimentally infected Rattus rattus. For IFAT, S. ratti larvae were used as antigen and S. ratti larval antigenic extracts were employed in WB and ELISA. Eleven S. ratti antigenic components were predominantly recognized by IgG antibodies in sera of patients with strongyloidiasis. There was a positive concordance for the three tests in 87.5% of the cases of strongyloidiasis. The negative concordance in the three tests was 94% and 97.5%, in patients with other intestinal parasitoses and healthy individuals, respectively. In cases of positive ELISA and negative IFAT results, diagnosis could be confirmed by WB. ELISA, IFAT, and WB using S. ratti antigens showed a high rate of sensitivity and specificity. In conclusion, WB using S. ratti larval extract was able to recognize 11 immunodominant antigenic components, showing to be a useful tool to define the diagnosis in cases of equivocal serology.




  11. Recent developments in dynamic testing of materials

    Directory of Open Access Journals (Sweden)

    Gilat Amos


    Full Text Available New techniques for dynamic characterization of materials that have been developed in the last three years (since the last DYMAT conference in 2012, and results from recent dynamic testing of Inconel 718 are presented. The first development is a dynamic punch test in which three dimensional Digital Image Correlation (DIC is used to measure the deformation of the rear surface of a specimen as it being penetrated. The second experimental technique that is under development is a dynamic tension experiment in which full-field strain measurement with DIC and full-field temperature measurement are done simultaneously during the test.

  12. Development history of the Hybrid Test Vehicle (United States)

    Trummel, M. C.; Burke, A. F.


    Phase I of a joint Department of Energy/Jet Propulsion Laboratory Program undertook the development of the Hybrid Test Vehicle (HTV), which has subsequently progressed through design, fabrication, and testing and evaluation phases. Attention is presently given to the design and test experience gained during the HTV development program, and a discussion is presented of the design features and performance capabilities of the various 'mule' vehicles, devoted to the separate development of engine microprocessor control, vehicle structure, and mechanical components, whose elements were incorporated into the final HTV design. Computer projections of the HTV's performance are given.

  13. Multiplex immunoassay for Lyme disease using VlsE1-IgG and pepC10-IgM antibodies: improving test performance through bioinformatics. (United States)

    Porwancher, Richard B; Hagerty, C Greg; Fan, Jianqing; Landsberg, Lisa; Johnson, Barbara J B; Kopnitsky, Mark; Steere, Allen C; Kulas, Karen; Wong, Susan J


    The Centers for Disease Control and Prevention currently recommends a 2-tier serologic approach to Lyme disease laboratory diagnosis, comprised of an initial serum enzyme immunoassay (EIA) for antibody to Borrelia burgdorferi followed by supplementary IgG and IgM Western blotting of EIA-positive or -equivocal samples. Western blot accuracy is limited by subjective interpretation of weakly positive bands, false-positive IgM immunoblots, and low sensitivity for detection of early disease. We developed an objective alternative second-tier immunoassay using a multiplex microsphere system that measures VlsE1-IgG and pepC10-IgM antibodies simultaneously in the same sample. Our study population comprised 79 patients with early acute Lyme disease, 82 patients with early-convalescent-phase disease, 47 patients with stage II and III disease, 34 patients post-antibiotic treatment, and 794 controls. A bioinformatic technique called partial receiver-operator characteristic (ROC) regression was used to combine individual antibody levels into a single diagnostic score with a single cutoff; this technique enhances test performance when a high specificity is required (e.g., ≥ 95%). Compared to Western blotting, the multiplex assay was equally specific (95.6%) but 20.7% more sensitive for early-convalescent-phase disease (89.0% versus 68.3%, respectively; 95% confidence interval [95% CI] for difference, 12.1% to 30.9%) and 12.5% more sensitive overall (75.0% versus 62.5%, respectively; 95% CI for difference, 8.1% to 17.1%). As a second-tier test, a multiplex assay for VlsE1-IgG and pepC10-IgM antibodies performed as well as or better than Western blotting for Lyme disease diagnosis. Prospective validation studies appear to be warranted.

  14. Multiplex Immunoassay for Lyme Disease Using VlsE1-IgG and pepC10-IgM Antibodies: Improving Test Performance through Bioinformatics ▿ (United States)

    Porwancher, Richard B.; Hagerty, C. Greg; Fan, Jianqing; Landsberg, Lisa; Johnson, Barbara J. B.; Kopnitsky, Mark; Steere, Allen C.; Kulas, Karen; Wong, Susan J.


    The Centers for Disease Control and Prevention currently recommends a 2-tier serologic approach to Lyme disease laboratory diagnosis, comprised of an initial serum enzyme immunoassay (EIA) for antibody to Borrelia burgdorferi followed by supplementary IgG and IgM Western blotting of EIA-positive or -equivocal samples. Western blot accuracy is limited by subjective interpretation of weakly positive bands, false-positive IgM immunoblots, and low sensitivity for detection of early disease. We developed an objective alternative second-tier immunoassay using a multiplex microsphere system that measures VlsE1-IgG and pepC10-IgM antibodies simultaneously in the same sample. Our study population comprised 79 patients with early acute Lyme disease, 82 patients with early-convalescent-phase disease, 47 patients with stage II and III disease, 34 patients post-antibiotic treatment, and 794 controls. A bioinformatic technique called partial receiver-operator characteristic (ROC) regression was used to combine individual antibody levels into a single diagnostic score with a single cutoff; this technique enhances test performance when a high specificity is required (e.g., ≥95%). Compared to Western blotting, the multiplex assay was equally specific (95.6%) but 20.7% more sensitive for early-convalescent-phase disease (89.0% versus 68.3%, respectively; 95% confidence interval [95% CI] for difference, 12.1% to 30.9%) and 12.5% more sensitive overall (75.0% versus 62.5%, respectively; 95% CI for difference, 8.1% to 17.1%). As a second-tier test, a multiplex assay for VlsE1-IgG and pepC10-IgM antibodies performed as well as or better than Western blotting for Lyme disease diagnosis. Prospective validation studies appear to be warranted. PMID:21367982

  15. Serologic tests for detecting antibodies against Mycobacterium bovis and Mycobacterium avium subspecies paratuberculosis in Eurasian wild boar (Sus scrofa scrofa). (United States)

    Boadella, Mariana; Lyashchenko, Konstantin; Greenwald, Reena; Esfandiari, Javan; Jaroso, Raquel; Carta, Tania; Garrido, Joseba M; Vicente, Joaquín; de la Fuente, José; Gortázar, Christian


    New tools to detect exposure of free-range Eurasian wild boar (Sus scrofa scrofa) to pathogenic mycobacteria would be valuable for improved disease surveillance and wildlife management. Two hundred sera from wild boar of known Mycobacterium bovis infection status were used to evaluate test suitability for the detection of antibodies against M. bovis and Mycobacterium avium subsp. paratuberculosis (or cross-reacting members of the M. avium complex). Two traditional enzyme-linked immunosorbent assays were evaluated using M. bovis purified protein derivative (bPPD) and paratuberculosis protoplasmatic antigen 3 (PPA3) as antigens, respectively, and a new point-of-care test format for bovine tuberculosis (bTB) that uses the innovative dual-path platform (DPP TB) test. The effect of individual factors (sex, age, lesions) on the diagnostic performance of the serologic tests was also determined. Although the DPP had a sensitivity of 89.6% and a specificity of 90.4%, for bPPD, the sensitivity was 79.2% and the specificity 100%. Both tests had a kappa agreement of 0.80. Sixty-five of 68 (95.6%) wild boar sera with antibodies against the PPA3 antigen corresponded to known M. bovis-infected wild boar. Significant differences were not observed in the bPPD and DPP readings among lesion categories or between age classes. A slight sex-related difference in sensitivity toward males in the DPP was found, but it was not detected in the bPPD enzyme-linked immunosorbent assay. The results support the use of antibody-based diagnostic tests for both large-scale and individual bTB testing of Eurasian wild boar and suggest that wild boar cannot be used as sentinels for infections caused by M. avium complex members.

  16. Development of testing metrics for military robotics (United States)

    Resendes, Raymond J.


    The use of robotics or unmanned systems offers significant benefits to the military user by enhancing mobility, logistics, material handling, command and control, reconnaissance, and protection. The evaluation and selection process for the procurement of an unmanned robotic system involves comparison of performance and physical characteristics such as operating environment, application, payloads and performance criteria. Testing an unmanned system for operation in an unstructured environment using emerging technologies, which have not yet been fully tested, presents unique challenges for the testing community. Standard metrics, test procedures, terminologies, and methodologies simplify comparison of different systems. A procedure was developed to standardize the test and evaluation process for UGVs. This procedure breaks the UGV into three components: the platform, the payload, and the command and control link. Standardized metrics were developed for these components which permit unbiased comparison of different systems. The development of these metrics and their application will be presented.

  17. Development of a Danish speech intelligibility test

    DEFF Research Database (Denmark)

    Nielsen, Jens Bo; Dau, Torsten


    Abstract A Danish speech intelligibility test for assessing the speech recognition threshold in noise (SRTN) has been developed. The test consists of 180 sentences distributed in 18 phonetically balanced lists. The sentences are based on an open word-set and represent everyday language....... The sentences were equalized with respect to intelligibility to ensure uniform SRTN assessments with all lists. In contrast to several previously developed tests such as the hearing in noise test (HINT) where the equalization is based on scored (objective) measures of word intelligibility, the present test used...... an equalization method based on subjective assessments of the sentences. The new equalization method is shown to create lists with less variance between the SRTNs than the traditional method. The number of sentence levels included in the SRTN calculation was also evaluated and differs from previous tests...

  18. Developing New Testing Methods for Nanosatellites Project (United States)

    National Aeronautics and Space Administration — Thermal modeling and Test plan to be carried out and developed by Goddard Space Flight Center. This project will be done in collaboration with partners at MIT and...

  19. Testbed For Aerothermal Test Technique Development Project (United States)

    National Aeronautics and Space Administration — It is proposed that a very low cost wind tunnel could be developed at JSC to provide engineers with the ability to directly run small tests focused on improving...

  20. Virological features associated with the development of broadly neutralizing antibodies to HIV-1. (United States)

    Moore, Penny L; Williamson, Carolyn; Morris, Lynn


    The development of a preventative HIV-1 vaccine remains a global public health priority. This will likely require the elicitation of broadly neutralizing antibodies (bNAbs) able to block infection by diverse viral strains from across the world. Understanding the pathway to neutralization breadth in HIV-1 infected humans will provide insights into how bNAb lineages arise, a process that probably involves a combination of host and viral factors. Here, we focus on the role of viral characteristics and evolution in shaping bNAbs during HIV-1 infection, and describe how these findings may be translated into novel vaccine strategies.

  1. Comparison between the Counter Immunoelectrophoresis Test and Mouse Neutralization Test for the Detection of Antibodies against Rabies Virus in Dog Sera

    Directory of Open Access Journals (Sweden)

    Luzia Helena Queiroz da Silva


    Full Text Available The detection of rabies antibodies is extremely valuable for epidemiological studies, determination of immune status in man, animals, and for the diagnosis of the disease. Several serological procedures have been described for this purpose. The present study reports a comparison between counterimmunoelectrophoresis test (CIET and mouse neutralization test (MNT in the detection of antibodies against rabies virus from 212 serum samples of vaccinated dogs. The agreement between both techniques was 79.7% and a significative association was demonstrated. The correlation coefficients between MNT and the CIET titers was determined considering 88 samples showing positive results in both techniques [CIET = 2 and MNT = 5 (0.13 IU/ml] and resulted r² = 0.7926 (p < 0.001. The performance of CIET system was technically simple, cheap and rapid, and thereby it could be useful for serological monitoring of dog vaccination campaigns as well as for individual analysis.

  2. Irradiation effects on antibody performance in the frame of biochip-based instruments development for space exploration (United States)

    Baqué, M.; Dobrijevic, M.; Le Postollec, A.; Moreau, T.; Faye, C.; Vigier, F.; Incerti, S.; Coussot, G.; Caron, J.; Vandenabeele-Trambouze, O.


    Several instruments based on immunoassay techniques have been proposed for life-detection experiments in the framework of planetary exploration but few experiments have been conducted so far to test the resistance of antibodies against cosmic ray particles. We present several irradiation experiments carried out on both grafted and free antibodies for different types of incident particles (protons, neutrons, electrons and 12C) at different energies (between 9 MeV and 50 MeV) and different fluences. No loss of antibodies activity was detected for the whole set of experiments except when considering protons with energy between 20 and 30 MeV (on free and grafted antibodies) and fluences much greater than expected for a typical planetary mission to Mars for instance. Our results on grafted antibodies suggest that biochip-based instruments must be carefully designed according to the expected radiation environment for a given mission. In particular, a surface density of antibodies much larger than the expected proton fluence would prevent significant loss of antibodies activity and thus assuring a successful detection.

  3. Development of a novel and efficient cell culture flocculation process using a stimulus responsive polymer to streamline antibody purification processes. (United States)

    Kang, Yun Kenneth; Hamzik, James; Felo, Michael; Qi, Bo; Lee, Julia; Ng, Stanley; Liebisch, Gregory; Shanehsaz, Behnam; Singh, Nripen; Persaud, Kris; Ludwig, Dale L; Balderes, Paul


    Recent advances in mammalian cell culture processes have significantly increased product titers, but have also resulted in substantial increases in cell density and cellular debris as well as process and product related impurities. As such, with improvements in titer, corresponding improvements in downstream processing are essential. In this study we have developed an alternative antibody harvest process that incorporates flocculation using a novel stimulus responsive polymer, benzylated poly(allylamine), followed by depth filtration. As tested on multiple antibodies, this process demonstrates high process yield, improved clearance of cells and cell debris, and efficient reduction of aggregates, host cell proteins (HCP) and DNA. A wide operating window was established for this novel flocculation process through design of experiments condition screening and optimization. Residual levels of impurities in the Protein A eluate were achieved that potentially meet requirements of drug substance and thus alleviate the burden for further impurities removal in subsequent chromatography steps. In addition, efficient clearance of residual polymer was demonstrated using a fluorescence tagged polymer in the presence of a stimulus reagent. The mechanism of HCP and aggregates removal during flocculation was also explored. This novel and efficient process can be easily integrated into current mAb purification platforms, and may overcome downstream processing challenges.

  4. Development and validation of a multiplex immunoassay for the simultaneous determination of serum antibodies to Bordetella pertussis, diphtheria and tetanus. (United States)

    van Gageldonk, Pieter G M; van Schaijk, Frank G; van der Klis, Fiona R; Berbers, Guy A M


    To increase testing of vaccine induced humoral immunity in immune surveillance studies and vaccine trials, a rapid and simple microsphere-based multiplex assay (pentaplex) was developed for the quantitation of IgG serum antibodies directed against the Bordetella pertussis antigens: Pertussis Toxin (Ptx), Filamentous hemagglutinin (FHA), Pertactin (Prn) and to Diphtheria toxin and Tetanus toxin. All individual antigens were covalently linked to carboxylated microspheres. The method was validated with different serum panels (n=60-78 samples). With the Multiplex Immunoassay (MIA) no evidence for bead interference between monoplex and pentaplex was found. The specificity of the method was shown by a heterologous inhibition of 92%. The pentaplex MIA appeared sensitive with lower limits of quantitation (LLOQ) well below those for ELISA (enzyme-linked immuno-sorbant assay). Assay reproducibility was high with intra-assay variability less than 10% and inter-assay variability below 14%. The reproducibility of the bead conjugation was good and beads could be stored up to at least 6 months without quality reduction. Importantly, the correlation of the pentaplex MIA with the individual ELISAs was excellent, R>0.98 for the Pertussis antigens and R=0.95 for Diphtheria and R=0.98 for Tetanus. Serum IgG antibodies to B. pertussis, Diphtheria and Tetanus can be measured easily, specific and reproducible using the pentaplex MIA. The pentaplex MIA shares features of the ELISA with the additional advantages of high sample throughput and small sample volumes and antigen required.

  5. Development of an antigen-capture enzyme-linked immunosorbent assay using monoclonal antibodies for detecting H6 avian influenza viruses. (United States)

    Chen, Yi-Tung; Tsao, Zak; Chang, Shu-Ting; Juang, Ron-Huay; Wang, Lih-Chiann; Chang, Chung-Ming; Wang, Ching-Ho


    The H6 subtype of avian influenza virus (AIV) infection occurs frequently in wild and domestic birds. AIV antigen detection is preferred for controlling AIV as birds are infected before they produce antibodies. The purpose of this study was to develop an early diagnostic method for AIV detection. Six monoclonal antibodies (mAbs) developed from a field H6N1 AIV strain were tested for their ability to bind to viruses. The two that showed the greatest binding ability to AIVs were used for antigen detection. An antigen-capture enzyme-linked immunosorbent assay (ELISA) to detect H6 AIVs was developed using these mAbs. One mAb was coated onto an ELISA plate as the capture antibody. The other mAb was used as the detector antibody after labeling with horseradish peroxidase. The antigen-capture ELISA detected H6N1 AIVs but not H5 AIVs, human H1N1, H3N2 influenza or other viruses. This antigen-capture ELISA could be used to specifically detect H6N1 AIV.

  6. The Utilization of a New Immunochromatographic Test in Detection of Helicobacter pylori Antibody from Maternal and Umbilical Cord Serum

    Directory of Open Access Journals (Sweden)

    Fu-Chen Kuo


    Full Text Available Background. Helicobacter pylori (H. pylori was linked with several extragastrointestinal diseases, including preeclampsia and intrauterine growth restriction of fetus. One of the signals which can be transferred from mother to fetus is the H. pylori IgG antibody. Aims. We utilized a commercial immunochromatographic kit to detect the antibody in maternal and cord serum. Methods. Three hundred and forty-six females were enrolled and the blood samples were collected on antenatal examination and on delivery. The maternal H. pylori infection was determined by stool H. pylori antigen test. Results. One hundred and five females (30.3% were H. pylori-infected, and the prevalence was higher in immigrants (43.5% than in Taiwanese (28.7%, P=0.058. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the kit were 77.1%, 88.0%, 73.6%, 89.8%, and 84.7%, respectively. This kit also had similar performance in cord serum. Comparing to the maternal result on delivery, this kit offered a consistent performance in antenatal maternal serum (kappa coefficient 0.92 and in cord serum (kappa coefficient 0.88. Conclusions. H. pylori IgG antibody can be transferred through the placenta into the fetal circulation. However, accuracy of the test kit needs to be evaluated before utilization in screening.

  7. False positive hepatitis C antibody test results in left ventricular assist device recipients: increased risk with age and transfusions (United States)

    Lee, Doreen; Colovai, Adriana; Levy, Dana; Vasovic, Ljiljana; Roach, Keith W.; Shuter, Jonathan; Goldstein, Daniel; D’Alessandro, David; Jorde, Ulrich P.; Muggia, Victoria A.


    Left ventricular assist devices (LVADs) have been successfully used in patients with heart failure. However, LVADs may trigger immune activation, leading to higher frequencies of autoantibodies. We describe the clinical, epidemiological, and laboratory characteristics of LVAD recipients with false positive hepatitis C (FPHC) serology among 39 consecutive adult LVAD recipients who bridged to heart transplantation from January 2007 to January 2013 at Montefiore Medical Center. FPHC patients were identified as those with post-LVAD positive hepatitis C ELISA antibody tests and negative confirmatory testing with hepatitis C RNA PCR and/or radioimmunoblot assay. Ten (26%) patients previously seronegative for hepatitis C were found to have FPHC after device placement. Of the 39 patients, 32 had HeartMate II devices. The mean age at LVAD placement was 55 years. FPHC correlated with older age at the time of LVAD implantation and with receipt of packed red blood cell transfusions, but not with gender, fresh frozen plasma transfusions, panel reactive antibodies, globulin fraction, rheumatoid factor, or anticardiolipin antibodies. Clinicians should be aware of this increased risk of FPHC in older LVAD patients and those more heavily transfused in order to avoid unnecessary apprehension and possible delay in transplantation. Further studies should be done to evaluate the possible relationship between transfused blood products and immunomodulation. PMID:28203425

  8. Transport Test Problems for Hybrid Methods Development

    Energy Technology Data Exchange (ETDEWEB)

    Shaver, Mark W.; Miller, Erin A.; Wittman, Richard S.; McDonald, Benjamin S.


    This report presents 9 test problems to guide testing and development of hybrid calculations for the ADVANTG code at ORNL. These test cases can be used for comparing different types of radiation transport calculations, as well as for guiding the development of variance reduction methods. Cases are drawn primarily from existing or previous calculations with a preference for cases which include experimental data, or otherwise have results with a high level of confidence, are non-sensitive, and represent problem sets of interest to NA-22.

  9. Development of thyroglobulin antibodies after GVAX immunotherapy is associated with prolonged survival. (United States)

    De Remigis, Alessandra; de Gruijl, Tanja D; Uram, Jennifer N; Tzou, Schey-Cherng; Iwama, Shintaro; Talor, Monica V; Armstrong, Todd D; Santegoets, Saskia J A M; Slovin, Susan F; Zheng, Lei; Laheru, Daniel A; Jaffee, Elizabeth M; Gerritsen, Winald R; van den Eertwegh, Alfons J M; Le, Dung T; Caturegli, Patrizio


    Cancer immunotherapy induces a variety of autoinflammatory responses, including those against the thyroid gland, which can be exploited to predict clinical outcomes. Considering the paucity of information about thyroid autoimmunity in patients receiving cancer vaccines, we designed our study to assess the development of thyroglobulin antibodies (TgAbs) in patients treated with GVAX (vaccine made of a tumor cell type transfected with GM-CSF) and/or ipilimumab and correlated seroconversion with survival. Using both in house and commercial ELISA assays, we measured TgAbs in patients with pancreatic (No. = 53), prostate (No. = 35) or colon (No. = 8) cancer, before and after treatment with GVAX only (No. = 34), GVAX plus ipilimumab (No. = 42) or ipilimumab (No. = 20), and correlated their levels with patient's survival, disease status and T-cell surface markers. Antibodies to thyroperoxidase, myeloperoxidase, proteinase 3, insulin and actin were also measured. TgAbs specifically developed after GVAX, independent of the underlying cancer (81% in prostate, 75% colon cancer and 76% pancreatic cancer) and co-administration of ipilimumab (75% in GVAX only and 78% in GVAX plus ipilimumab). This TgAbs seroconversion could be detected mainly by the in house assay, suggesting that the thyroglobulin epitopes recognized by the antibodies induced by GVAX are different from the epitopes seen in the classic form of Hashimoto thyroiditis. Notably, TgAbs seroconversion was associated with significantly prolonged survival (p = 0.01 for pancreas and p = 0.005 for prostate cancer). In conclusion, GVAX immunotherapy induces the appearance of TgAbs that recognize a unique antigenic repertoire and associate with prolonged survival.

  10. Thermomechanical Multiaxial Fatigue Testing Capability Developed (United States)


    Structural components in aeronautical gas turbine engines typically experience multiaxial states of stress under nonisothermal conditions. To estimate the durability of the various components in the engine, one must characterize the cyclic deformation and fatigue behavior of the materials used under thermal and complex mechanical loading conditions. To this end, a testing protocol and associated test control software were developed at the NASA Lewis Research Center for thermomechanical axial-torsional fatigue tests. These tests are to be performed on thin-walled, tubular specimens fabricated from the cobalt-based superalloy Haynes 188. The software is written in C and runs on an MS-DOS based microcomputer.

  11. Development of phytotoxicity tests using wetland species

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, M.K.; Fairchild, J.F. [National Biological Survey, Columbia, MO (United States)


    Laboratory phytotoxicity tests used to assess contaminant effects may not effectively protect wetland communities. The authors are developing routine culture and testing methods for selected fresh water plants, that can be used in risk assessments and monitoring of existing wetland systems. Utility of these tests includes evaluating the effects of point or non-point source contamination that may cause water or sediment quality degradation. Selected species include algae (blue-green, green), phytoflagellates (Chlamydomonas, Euglena), and floating or submerged vascular plants (milfoil, coontail, wild celery, elodea, duckweed). Algae toxicity tests range from 2-d, 4-d, and 7 day tests, and macrophyte tests from 10-d to 14 days. Metribuzin and boron are the selected contaminants for developing the test methods. Metribuzin, a triazinone herbicide, is a photosystem 11 inhibitor, and is commonly used for control of grass and broad-leaf plants. As a plant micronutrient, boron is required in very small amounts, but excessive levels can result in phytotoxicity or accumulation. The investigations focus on the influence of important factors including the influence of light quality and quantity, and nutrient media. Reference toxicant exposures with potassium chloride are used to establish baseline data for sensitivity and vitality of the plants. These culture and test methods will be incorporated into recommendations for standard phytotoxicity test designs.

  12. Development of a monoclonal antibody-based enzyme-linked immunosorbent assay to quantify soluble beta-glucans in oats and barley. (United States)

    Rampitsch, Christof; Ames, Nancy; Storsley, Joanne; Marien, Lindsay


    A set of 31 murine monoclonal antibodies was produced against (1-->3,1-->4)beta-d-glucan from oats (Avena sativa L.) chemically cross-linked to keyhole limpet hemocyanin. Monoclonal antibodies were tested for their cross-reactivity to related and unrelated polysaccharides. The antibodies reacted strongly to unmodified beta-glucan from oats and barley (Hordeum vulgare L.) and to lichenan from Icelandic moss, a polysaccharide with a structure similar to that of beta-glucan but which is not encountered in cereals. Cross-reaction to other polysaccharides tested was minimal at physiological levels. An enzyme-linked immunosorbent assay (ELISA) that could routinely detect and quantify nanogram levels of soluble beta-glucan extracted from the flour of oats or barley was designed with one of these monoclonal antibodies. The beta-glucan extraction procedure from ground oat and barley samples and the ELISA were both optimized for reproducibility, accuracy, and throughput, and results were compared to values obtained from an established, commercially available enzyme-based assay. Correlations between the two assays were consistently high (r (2) > 0.9), indicating that the ELISA presented in this paper is a valuable alternative for assaying beta-glucan levels in cereals and cereal products, both routinely and in preparations in which beta-glucans are present in nanogram amounts. Development of the extraction procedure for ELISA is discussed.

  13. Development of the nanotiter plate for use in antibody and cell array technologies (United States)

    Ramdutt, Devin; Lui, Rodney; Davies, Kerrie; Boswell, Rod W.; dos Remedios, Cristobal G.; Charles, Christine; Bilek, Marcela M.; McKenzie, David R.


    The design and fabrication of biomedical tools using techniques common in microelectronics is becoming established procedure. In our research, we use gaseous plasma dry etching to form microstructures on silicon wafers. These are intended for use in capturing and binding antibodies and live cells in an array to be used in High Throughput Screening (HTS) and High Content Screening (HCS) of new pharmaceuticals. We call this new arraying plate the "Nanotiter" plate. The benefit of our design (100 x 100 wells in a 25 x 25 mm array) over current 96-, 384- and 1056-well microtiter plates are that the number of samples (wells) that can be tested in one plate scan can be substantially increased, the wells can be rapidly and effectively washed, and the well surfaces can be modified to modulate ligand binding. Simple crowding of wells on a plate can result in cross contamination of samples in adjacent wells during the washing. Furthermore, motile cells may migrate between the wells. 1056 microtiter plates currently cannot be washed, and washing 384 plates is problematic. Our design incorporates plasma-deposited polymers that functionally bind antibodies (or other proteins) in but not between wells. Furthermore, the wells can be shaped to minimize cell migration. Inverting the plate on a wash solution allows unbound cells to simply fall away under gravity thus minimising the contamination of adjacent wells. Thus, our Nanotiter plate represents a substantial improvement over existing technology.

  14. Immunomodulatory therapies for relapsing-remitting multiple sclerosis: monoclonal antibodies, currently approved and in testing. (United States)

    Craddock, Jessica; Markovic-Plese, Silva


    Relapsing-remitting multiple sclerosis (RRMS), a CNS inflammatory demyelinating disease, is one of the most prevalent causes of chronic disability in young adults. Studies of the disease pathogenesis have identified multiple therapeutic targets. The number of approved disease modifying therapies has almost doubled within the past 5 years, which creates a challenge for medical professionals to stay abreast of their use in everyday practice. This manuscript provides an overview of available injectable, oral, and intravenous therapies for RRMS, and offers guidance in selecting an appropriate therapy. Focus is on the recently approved and emerging monoclonal antibody therapies, because they offer more selective and superior therapeutic efficacy compared with injectable and oral disease modifying therapies. We discuss the outlook for monoclonal antibodies and their role in RRMS treatment in the future.

  15. Anti-myeloperoxidase antibodies attenuate the monocyte response to LPS and shape macrophage development (United States)

    Popat, Reena J.; Hakki, Seran; Coughlan, Alice M.; Watson, Julie; Little, Mark A.; Spickett, Corinne M.; Lavender, Paul; Afzali, Behdad; Kemper, Claudia; Robson, Michael G.


    Anti-neutrophil cytoplasmic antibody (ANCA) vasculitis is characterized by the presence of autoantibodies to myeloperoxidase and proteinase-3, which bind monocytes in addition to neutrophils. While a pathological effect on neutrophils is acknowledged, the impact of ANCA on monocyte function is less well understood. Using IgG from patients we investigated the effect of these autoantibodies on monocytes and found that anti-myeloperoxidase antibodies (MPO-ANCA) reduced both IL-10 and IL-6 secretion in response to LPS. This reduction in IL-10 and IL-6 depended on Fc receptors and enzymatic myeloperoxidase and was accompanied by a significant reduction in TLR-driven signaling pathways. Aligning with changes in TLR signals, oxidized phospholipids, which function as TLR4 antagonists, were increased in monocytes in the presence of MPO-ANCA. We further observed that MPO-ANCA increased monocyte survival and differentiation to macrophages by stimulating CSF-1 production. However, this was independent of myeloperoxidase enzymatic activity and TLR signaling. Macrophages differentiated in the presence of MPO-ANCA secreted more TGF-β and further promoted the development of IL-10– and TGF-β–secreting CD4+ T cells. Thus, MPO-ANCA may promote inflammation by reducing the secretion of antiinflammatory IL-10 from monocytes, and MPO-ANCA can alter the development of macrophages and T cells to potentially promote fibrosis. PMID:28138552

  16. Development of monoclonal antibody-based sandwich ELISA for detection of dextran. (United States)

    Wang, Sheng-Yu; Li, Zhe; Wang, Xian-Jiang; Lv, Sha; Yang, Yun; Zeng, Lian-Qiang; Luo, Fang-Hong; Yan, Jiang-Hua; Liang, Da-Feng


    Dextran as anti-nutritional factor is usually a result of bacteria activity and has associated serial problems during the process stream in the sugar industry and in medical therapy. A sensitive method is expected to detect dextran quantitatively. Here we generated four monoclonal antibodies (MAbs) against dextran using dextran T40 conjugated with bovine serum albumin (BSA) as immunogen in our lab following hybridoma protocol. Through pairwise, an MAb named D24 was determined to be conjugated with horseradish peroxidase (HRP) and was used in the establishment of a sensitive sandwich enzyme-linked immunosorbent assay (ELISA) method for determination of dextran, in which MAb D9 was chosen as a capture antibody. The detection limit and working scope of the developed sandwich ELISA method were 3.9 ng/mL and 7.8-500 ng/mL with a correlation coefficient of 0.9909. In addition, the cross-reaction assay demonstrated that the method possessed high specificity with no significant cross-reaction with dextran-related substances, and the recovery rate ranged from 96.35 to 102.00%, with coefficient of variation ranging from 1.58 to 6.94%. These results indicated that we developed a detection system of MAb-based sandwich ELISA to measure dextran and this system should be a potential tool to determine dextran levels.

  17. Development of an enzyme-linked immunosorbent assay for the monitoring and surveillance of antibodies to porcine epidemic diarrhea virus based on a recombinant membrane protein. (United States)

    Fan, Jing-Hui; Zuo, Yu-Zhu; Shen, Xiao-Qiang; Gu, Wen-Yuan; Di, Jing-Mei


    The recent dramatic increase in reported cases of porcine epidemic diarrhea (PED) in pig farms is a potential threat to the global swine industry. Therefore, the accurate diagnosis, serological monitoring, and surveillance of specific antibodies in pigs resulting from porcine epidemic diarrhea virus (PEDV) infection or vaccination would be essential in helping to control the spread of PED. We developed and validated an indirect enzyme-linked immunosorbent assay (ELISA) based on the recombinant membrane (M) protein of PEDV. To detect PEDV antibodies in eight herds, 382 serum samples were collected from sows that had been immunized with a PED vaccine, and screened using the developed ELISA in parallel with a serum neutralization (SN) assay. Of the tested samples, 276 were positive for the presence of PEDV antibodies according to both assays, while 98 were negative. An excellent agreement between the ELISA and the SN assay was observed (kappa=0.947; 95% confidence interval=0.910-0.984; McNemar's test, P=0.727). No cross-reaction was detected for the developed ELISA with other coronaviruses or other common pig pathogens. The developed ELISA could be used for serological evaluation and indirect diagnosis of PED infection.

  18. Development of Lateral-flow Immunoassay for WSSV with Polyclonal Antibodies Raised against Recombinant VP (19+28) Fusion Protein

    Institute of Scientific and Technical Information of China (English)

    Qing-yu CHENG; Xiao-lin MENG; Jin-ping XU; Wei LU; Jian WANG


    We have developed a sensitive and rapid lateral-flow immunoassay (LFIA) for WSSV,using colloidal gold as an indicator.The fusion protein,VP (19+28),was expressed in E.coli,purified and used to prepare polyclonal antibodies.The purified anti-VP (19+28) IgG were conjugated with colloidal gold.Unconjugated anti-VP (19+28) IgG and goat anti-rabbit IgG were immobilized on nitrocellulose membranes.After assembly,three groups (5 individual animals in each group) of shrimp samples were tested which included healthy,moribund and dead shrimps.For each group,three different tissues (body juices,gills and hepatopancreas) were tested at the same time.In parallel,all the samples were also analyzed using PCR for comparison.Out of 45 samples tested,30 were detected as positive while 15 were classified as negative.The results of LFIA correlate with those obtained by the PCR analysis,indicating that these two detection methods have the same efficacy in the limited number of samples tested in this preliminary study.

  19. DTU PMU Laboratory Development - Testing and Validation

    DEFF Research Database (Denmark)

    Garcia-Valle, Rodrigo; Yang, Guang-Ya; Martin, Kenneth E.;


    This is a report of the results of phasor measurement unit (PMU) laboratory development and testing done at the Centre for Electric Technology (CET), Technical University of Denmark (DTU). Analysis of the PMU performance first required the development of tools to convert the DTU PMU data into IEEE...... standard, and the validation is done for the DTU-PMU via a validated commercial PMU. The commercial PMU has been tested from the authors' previous efforts, where the response can be expected to follow known patterns and provide confirmation about the test system to confirm the design and settings....... In a nutshell, having 2 PMUs that observe same signals provides validation of the operation and flags questionable results with more certainty. Moreover, the performance and accuracy of the DTU-PMU is tested acquiring good and precise results, when compared with a commercial phasor measurement device, PMU-1....

  20. Development of Magnetorheological Engine Mount Test Rig


    Md Yunos Mohd Razali; Harun Mohamad Hafiz; Sariman M.Z.; Mat Yamin A.K.


    Ride comfort is an important factor in any road vehicle performance. Nonetheless, passenger ride comfort is sometimes affected by the vibrations resulting from the road irregularities. Vehicle ride comfort is also often compromised by engine vibration. Engine mount is one of the devices which act as vibration isolator from unwanted vibration from engine to the driver and passengers. This paper explains the development of the test rig used for laboratory testing of Magnetorheological (MR) engi...

  1. Development of new hole expansion testing method (United States)

    Kim, Hyunok; Shang, Jianhui; Beam, Kevin; Samant, Anoop; Hoschouer, Cliff; Dykeman, Jim


    This paper introduces a new hole expansion (HE) testing method that could be more relevant to the edge cracking problem observed in stamping advanced high strength steel (AHSS). The new testing method adopted a large hole diameter of 75 mm compared to the standard hole diameter of 10 mm. An inline monitoring system was developed to visually monitor the hole edge cracking during the test and synchronize the load-displacement data with the recorded video for capturing the initial crack. A new hole expansion testing method was found to be effective in evaluating the edge cracking by considering the effects of material properties and trimming methods. It showed a much larger difference, up to 11%, of the HE ratio between DP980 and TRIP780 compared to the standard HE testing method giving less than a 2% difference.

  2. Test Bench Development for Femur Stability Assessment

    Directory of Open Access Journals (Sweden)



    Full Text Available This paper shows the design and development of a test bench for humanfemurs. The main uses of this test bench will run from artificial femurs comparisonwith real femurs, to join stability assessment after bone a fracture repair. Amongthis uses is specially designed for condylar fractures testing. The test bench isdeveloped from a self-made existing tensile/compression testing machine. Thedesign procedure is supported by a literature review about the bone mechanicalbehavior and composition generally and the knee joint performance and repairparticularly. On the basis of this review, the machine was designed to simulate theadduction and abduction movements of the joint. The magnitudes to be measuredare: the compression force, the bone displacement (vertical and the knee jointrotation

  3. Field evaluation of a rapid diagnostic test to detect antibodies in human toxocariasis. (United States)

    Lim, P K C; Yamasaki, H; Mak, J W; Wong, S F; Chong, C W; Yap, I K S; Ambu, S; Kumarasamy, V


    Human toxocariasis which is caused mainly by the larvae of Toxocara canis and Toxocara cati, is a worldwide zoonotic disease that can be a potentially serious human infection. The enzyme-linked immunosorbent assay (ELISA) using T. canis excretory-secretory (TES) antigens harvested from T. canis larvae is currently the serological test for confirming toxocariasis. An alternative to producing large amounts of Toxocara TES and improved diagnosis for toxocariasis is through the development of highly specific recombinant antigens such as the T. canis second stage larva excretory-secretory 30 kDa protein (recTES-30). The aim of this study was to evaluate the sensitivity and specificity of a rapid diagnostic kit (RDT, named as iToxocara kit) in comparison to recTES-30 ELISA in Serendah Orang Asli village in Selangor, Malaysia. A total of 133 subjects were included in the study. The overall prevalence rates by ELISA and RDT were 29.3% and 33.1%, respectively, with more positive cases detected in males than females. However, no association was found between toxocariasis and gender or age. The percentage sensitivity, specificity, positive predictive value and negative predictive value of RDT were 85.7%, 90.1%, 80% and 93.2%, respectively. The prevalence for toxocariasis in this population using both ELISA and RDT was 27.1% (36/133) and the K-concordance test suggested good agreement of the two tests with a Cohen's kappa of 0.722, Ptoxocariasis.

  4. Passive haemagglutination test for human neurocysticercosis immunodiagnosis: I. Standardization and evaluation of the passive haemagglutination test for the detection of anti-Cysticercus cellulosae antibodies

    Directory of Open Access Journals (Sweden)

    Mirthes Ueda


    Full Text Available A passive haemagglutination test (PHA for human neurocysticercosis was standardized and evaluated for the detection of specific antibodies to Cysticercus cellulosae in cerebrospinal fluid (CSF. For the assay, formaldehyde-treated group O Rh-human red cells coated with the cysticerci crude total saline extract (TS antigen were employed. A total of 115 CSF samples from patients with neurocysticercosis was analysed, of these 94 presented reactivity, corresponding to 81.7% sensitivity, in which confidence limit of 95% probability (CL95% ranged from 74.5% to 88.9%. Eighty-nine CSF samples derived from individuals of control group presented as nonreactive in 94.4% (CL95% from 89.6% to 99.2%. The positive and negative predictive values were 1.4% and 99.9%, respectively, considering the mean rate of that this assay provide a rapid, highly reproducible, and moderately sensitive mean of detecting specific antibodies in CSF samples.

  5. A case of Crohn's disease that developed anti-infliximab and anti-adalimumab antibodies. (United States)

    Takahashi, Kenichiro; Fujimoto, Takehide; Shioya, Makoto; Nishida, Atsushi; Bamba, Shigeki; Inatomi, Osamu; Imaeda, Hirotsugu; Kitoh, Katsuyuki; Andoh, Akira


    There are few reports about the rapid appearance of anti-adalimumab antibodies in patients with Crohn's disease positive for anti-infliximab antibodies. We report the case of a 29-year-old female patient with a diagnosis of Crohn's disease who revealed a loss of response to infliximab due to high levels of antibodies to infliximab, and did not respond to the subsequent therapy by adalimumab, with a rapid appearance of antibodies to adalimumab. As one of the possible mechanisms of non-response to adalimumab, immunologic reactivity of infliximab to adalimumab was suspected, since the patient's IgG that was obtained just before the induction of adalimumab reacted with infliximab and adalimumab. We should pay attention to the easy appearance of anti-adalimumab antibodies in association with reactivity of anti-infliximab antibodies to adalimumab in patients with high levels of anti-infliximab antibodies.

  6. Development of an in Vitro Potency Assay for Anti-anthrax Lethal Toxin Neutralizing Antibodies

    Directory of Open Access Journals (Sweden)

    Sjoerd Rijpkema


    Full Text Available Lethal toxin (LT of Bacillus anthracis reduces the production of a number of inflammatory mediators, including transcription factors, chemokines and cytokines in various human cell lines, leading to down-regulation of the host inflammatory response. Previously we showed that the reduction of interleukin-8 (IL-8 is a sensitive marker of LT-mediated intoxication in human neutrophil-like NB-4 cells and that IL-8 levels are restored to normality when therapeutic monoclonal antibodies (mAb with toxin-neutralising (TN activity are added. We used this information to develop cell-based assays that examine the effects of TN therapeutic mAbs designed to treat LT intoxication and here we extend these findings. We present an in vitro assay based on human endothelial cell line HUVEC jr2, which measures the TN activity of therapeutic anti-LT mAbs using IL-8 as a marker for intoxication. HUVEC jr2 cells have the advantage over NB-4 cells that they are adherent, do not require a differentiation step and can be used in a microtitre plate format and therefore can facilitate high throughput analysis. This human cell-based assay provides a valid alternative to the mouse macrophage assay as it is a more biologically relevant model of the effects of toxin-neutralising antibodies in human infection.

  7. Development of robust antibody purification by optimizing protein-A chromatography in combination with precipitation methodologies. (United States)

    Chollangi, Srinivas; Parker, Ray; Singh, Nripen; Li, Yi; Borys, Michael; Li, Zhengjian


    To be administered to patients, therapeutic monoclonal antibodies must have very high purity, with process related impurities like host-cell proteins (HCPs) and DNA reduced to Protein-A chromatography as a capture step has been the work horse for clearing a large proportion of these impurities. However, remaining levels of process and product related impurities still present significant challenges on the development of polishing steps further downstream. In this study, we have incorporated high throughput screening to evaluate three areas of separation: (i) Harvest treatment; (ii) Protein-A Chromatography; and (iii) Low pH Viral Inactivation. Precipitation with low pH treatment of cell culture harvest resulted in selective removal of impurities while manipulating the pH of wash buffers used in Protein-A chromatography and incorporating wash additives that disrupt various modes of protein-protein interaction resulted in further and more pronounced reduction in impurity levels. In addition, our study also demonstrate that optimizing the neutralization pH post Protein-A elution can result in selective removal of impurities. When applied over multiple mAbs, this optimization method proved to be very robust and the strategy provides a new and improved purification process that reduces process related impurities like HCPs and DNA to drug substance specifications with just one chromatography column and open avenues for significant decrease in operating costs in monoclonal antibody purification.

  8. Transgenic Anopheles stephensi coexpressing single-chain antibodies resist Plasmodium falciparum development. (United States)

    Isaacs, Alison T; Jasinskiene, Nijole; Tretiakov, Mikhail; Thiery, Isabelle; Zettor, Agnès; Bourgouin, Catherine; James, Anthony A


    Anopheles stephensi mosquitoes expressing m1C3, m4B7, or m2A10 single-chain antibodies (scFvs) have significantly lower levels of infection compared to controls when challenged with Plasmodium falciparum, a human malaria pathogen. These scFvs are derived from antibodies specific to a parasite chitinase, the 25 kDa protein and the circumsporozoite protein, respectively. Transgenes comprising m2A10 in combination with either m1C3 or m4B7 were inserted into previously-characterized mosquito chromosomal "docking" sites using site-specific recombination. Transgene expression was evaluated at four different genomic locations and a docking site that permitted tissue- and sex-specific expression was researched further. Fitness studies of docking site and dual scFv transgene strains detected only one significant fitness cost: adult docking-site males displayed a late-onset reduction in survival. The m4B7/m2A10 mosquitoes challenged with P. falciparum had few or no sporozoites, the parasite stage infective to humans, in three of four experiments. No sporozoites were detected in m1C3/m2A10 mosquitoes in challenge experiments when both genes were induced at developmentally relevant times. These studies support the conclusion that expression of a single copy of a dual scFv transgene can completely inhibit parasite development without imposing a fitness cost on the mosquito.

  9. CICC Joint Development and Test for the Test Facility

    Institute of Scientific and Technical Information of China (English)

    武玉; 翁佩德


    The superconducting joint of the NbTi Cable-in -conduit Conductor (CICC) has been developed and tested on the magnet test facility at Institute of Plasma Physics, Chinese Academy of Sciences. The CICC is composed of (2NbTi+1Cu)×3×3×(6+1tube) strands each with 0.85 mm in diameter, which has been developed for a central solenoid model coil. The effective length of the joint is about 500 mm. There have been two common fabrication modes,one of them is to integrate the 2 CICC terminals with the copper substrate via lead-soldering, and the other is to mechanically compress the above two parts into an integrated unit. In the current range from 2 kA to 10 kA the joint resistance changes slightly. Up to now, 11 TF magnets, a central solenoid model coil, a central solenoid prototype coil, and a large PF model coil of PF large coil have been completed via the latter joint in the test facility.

  10. Perceived empathy of service providers mediates the association between perceived discrimination and behavioral intention to take up HIV antibody testing again among men who have sex with men.

    Directory of Open Access Journals (Sweden)

    Jing Gu

    Full Text Available HIV antibody testing is a key measure of HIV prevention for men who have sex with men (MSM. The World Health Organization recommends sexually active and at-risk MSM to take up HIV antibody testing regularly. This study aimed to investigate the prevalence of behavioral intention to take up HIV antibody testing in the next six months among Hong Kong MSM who were ever-testers. An anonymous cross-sectional survey recruited 326 MSM who had taken up HIV antibody testing from gay-friendly venues and internet in Hong Kong. Of the participants, 40.8% had had unprotected anal intercourse with regular or non-regular male sex partners in the last six months; they were at risk of HIV transmission despite experience in HIV antibody testing. Only 37.2% showed a strong intention to take up HIV antibody testing again in the next six months. Adjusted analysis showed that both perceived discrimination toward Hong Kong MSM (AOR = .60, 95% CI: .36-.98 and the CARE Measure assessing perceived empathy of service providers (AOR = 1.05, 95% CI: 1.02-1.08 were significantly associated with intention for retesting. Perceived discrimination, however, became statistically non-significant (AOR = .68, 95% CI: .41-1.14, when both CARE Measure and perceived discrimination entered into the adjusted model. It is warranted to increase HIV retesting rate by removing perceived discrimination and reducing the negative effect of perceived discrimination through enhancement of empathy of service providers.

  11. Isoimmunization with anti-U antibody. (United States)

    Turner, R J; Holder, W T; McCord, D L


    Isoimmunization with anti-U antibody is a rare but significant cause of hemolytic disease in black newborns. In this case report, an lgG antibody stimulated by fetomaternal transfusion produced a positive direct Coombs' test on cord blood but not neonatal hyperbilirubinemia. A review of the literature suggests the pathophysiology is similar to Rh isoimmunization. The anti-U antibody may develop as a result of pregnancy or blood transfusion in the 1.2 percent of American blacks who are at risk for developing the antibody. The principles of treatment employed in Rh isoimmunization can be successfully used in isoimmunization due to anti-U.

  12. Review for the generalist: The antinuclear antibody test in children - When to use it and what to do with a positive titer

    Directory of Open Access Journals (Sweden)

    Sailer-Hoeck Michaela


    Full Text Available Abstract The antinuclear antibody test (ANA is a much overused test in pediatrics. The ANA does have a role in serologic testing but it should be a very limited one. It is often ordered as a screening test for rheumatic illnesses in a primary care setting. However, since it has low specificity and sensitivity for most rheumatic and musculoskeletal illnesses in children, it should not be ordered as a screening test for non-specific complaints such as musculoskeletal pain. It should only be used as a diagnostic test for children with probable Systemic Lupus Erythematosus (SLE or Mixed Connective Tissue Disease, (MCTD and other possible overlap-like illnesses. Such children should have developed definite signs and symptoms of a disease before the ANA is ordered. This review presents data supporting these conclusions and a review of the ANA literature in adults and children. By limiting ANA testing, primary care providers can avoid needless venipuncture pain, unnecessary referrals, extra medical expenses, and most importantly, significant parental anxieties. It is best not to do the ANA test in most children but if it ordered and is positive in a low titer (

  13. Ice slurry cooling development and field testing

    Energy Technology Data Exchange (ETDEWEB)

    Kasza, K.E. [Argonne National Lab., IL (United States); Hietala, J. [Northern States Power Co., Minneapolis, MN (United States); Wendland, R.D. [Electric Power Research Inst., Palo Alto, CA (United States); Collins, F. [USDOE, Washington, DC (United States)


    A new advanced cooling technology collaborative program is underway involving Argonne National Laboratory (ANL), Northern States Power (NSP) and the Electric Power Research Institute (EPRI). The program will conduct field tests of an ice slurry distributed load network cooling concept at a Northern States Power utility service center to further develop and prove the technology and to facilitate technology transfer to the private sector. The program will further develop at Argonne National Laboratory through laboratory research key components of hardware needed in the field testing and develop an engineering data base needed to support the implementation of the technology. This program will sharply focus and culminate research and development funded by both the US Department of Energy and the Electric Power Research Institute on advanced cooling and load management technology over the last several years.

  14. Ice slurry cooling development and field testing

    Energy Technology Data Exchange (ETDEWEB)

    Kasza, K.E. (Argonne National Lab., IL (United States)); Hietala, J. (Northern States Power Co., Minneapolis, MN (United States)); Wendland, R.D. (Electric Power Research Inst., Palo Alto, CA (United States)); Collins, F. (USDOE, Washington, DC (United States))


    A new advanced cooling technology collaborative program is underway involving Argonne National Laboratory (ANL), Northern States Power (NSP) and the Electric Power Research Institute (EPRI). The program will conduct field tests of an ice slurry distributed load network cooling concept at a Northern States Power utility service center to further develop and prove the technology and to facilitate technology transfer to the private sector. The program will further develop at Argonne National Laboratory through laboratory research key components of hardware needed in the field testing and develop an engineering data base needed to support the implementation of the technology. This program will sharply focus and culminate research and development funded by both the US Department of Energy and the Electric Power Research Institute on advanced cooling and load management technology over the last several years.

  15. Passive immunization against dental caries and periodontal disease: development of recombinant and human monoclonal antibodies. (United States)

    Abiko, Y


    Indigenous micro-organisms in the oral cavity can cause two major diseases, dental caries and periodontal diseases. There is neither agreement nor consensus as to the actual mechanisms of pathogenesis of the specific virulence factors of these micro-organisms. The complexity of the bacterial community in dental plaque has made it difficult for the single bacterial agent of dental caries to be determined. However, there is considerable evidence that Streptococcus mutans is implicated as the primary causative organism of dental caries, and the cell-surface protein antigen (SA I/II) as well as glucosyltransferases (GTFs) produced by S. mutans appear to be major colonization factors. Various forms of periodontal diseases are closely associated with specific subgingival bacteria. Porphyromonas gingivalis has been implicated as an important etiological agent of adult periodontitis. Adherence of bacteria to host tissues is a prerequisite for colonization and one of the important steps in the disease process. Bacterial coaggregation factors and hemagglutinins likely play major roles in colonization in the subgingival area. Emerging evidence suggests that inhibition of these virulence factors may protect the host against caries and periodontal disease. Active and passive immunization approaches have been developed for immunotherapy of these diseases. Recent advances in mucosal immunology and the introduction of novel strategies for inducing mucosal immune responses now raise the possibility that effective and safe vaccines can be constructed. In this regard, some successful results have been reported in animal experimental models. Nevertheless, since the public at large might be skeptical about the seriousness of oral diseases, immunotherapy must be carried out with absolute safety. For this goal to be achieved, the development of safe antibodies for passive immunization is significant and important. In this review, salient advances in passive immunization against caries

  16. Antinuclear antibody panel (United States)

    ... page: // 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 ...

  17. Development and validation of a homogeneous mobility shift assay for the measurement of infliximab and antibodies-to-infliximab levels in patient serum. (United States)

    Wang, Shui-Long; Ohrmund, Linda; Hauenstein, Scott; Salbato, Jared; Reddy, Rukmini; Monk, Patrick; Lockton, Steven; Ling, Nicholas; Singh, Sharat


    Antibody-based drugs such as infliximab (IFX) are effective for the treatment of inflammatory bowel disease (IBD) and other immune-mediated disorders. The development of antibodies against these drugs may result in unfavorable consequences, including the loss of drug efficacy, hypersensitivity reactions, and other adverse events. Therefore, accurate monitoring of serum drug and anti-drug antibody levels should be an important part of therapy for patients being treated with an antibody-based drug. Current methods for the assessment of anti-drug antibodies and drug levels, involving various bridging ELISA and radioimmunoassay techniques, are limited by their sensitivity, interference, and/or complexity. To overcome these limitations, we have developed a non-radiolabeled homogeneous mobility shift assay (HMSA) to measure the antibodies-to-infliximab (ATI) and IFX levels in serum samples. Full method validation was performed on both the ATI- and IFX-HMSA, and the clinical sample test results were also compared with those obtained from a bridging ELISA method to evaluate the difference in performance between the two assays. Validation of the ATI-HMSA revealed a lower limit of quantitation of 0.012 μg/mL in serum. The linear range of quantitation was 0.029-0.54 μg/mL. The intra- and inter-assay precision was less than 20% of coefficient of variation (CV), and the accuracy (% error) of the assay was less than 20%. In serum samples, ATI as low as 0.036 μg/mL can be measured, even in the presence of 60 μg/mL of IFX in the serum. Sera from 100 healthy subjects were tested to determine the cut point of the assay. ATI-positive samples that had been previously analyzed by using a bridging ELISA from 100 patients were also measured by the new method. There was a high correlation between the two methods for ATI levels (pELISA method. Validation of the mobility shift IFX assay also showed high assay sensitivity, precision and accuracy. The HMSA method may also be applied to

  18. Bayesian estimation of sensitivity and specificity of Coxiella burnetii antibody ELISA tests in bovine blood and milk

    DEFF Research Database (Denmark)

    Paul, Suman; Toft, Nils; Agerholm, Jørgen S.;


    Serological tests for Coxiella burnetii (the causative agent of Q fever) antibodies are usually based on enzyme linked immunosorbent assay (ELISA) although this method is not thoroughly evaluated. The objective of this study was to determine the sensitivity and specificity of an ELISA for detection...... of the ELISA methods on milk and blood were equal at 0.99. No conditional dependence was observed between the specificity estimates of the two test methods. However, the sensitivity estimates of both tests were significantly reduced when conditional covariances ≥40 were used. Collection of milk samples from...... to positive (S/P) cut-off of 40 for both blood and milk ELISAs. At this cut-off, sensitivity of milk ELISA was 0.86 (95% posterior credibility interval [PCI] [0.76; 0.96]). This was slightly but insignificantly higher than sensitivity of blood ELISA (0.84; 95% PCI [0.75; 0.93]). The specificity estimates...

  19. Development of Magnetorheological Engine Mount Test Rig

    Directory of Open Access Journals (Sweden)

    Md Yunos Mohd Razali


    Full Text Available Ride comfort is an important factor in any road vehicle performance. Nonetheless, passenger ride comfort is sometimes affected by the vibrations resulting from the road irregularities. Vehicle ride comfort is also often compromised by engine vibration. Engine mount is one of the devices which act as vibration isolator from unwanted vibration from engine to the driver and passengers. This paper explains the development of the test rig used for laboratory testing of Magnetorheological (MR engine mount characterization. MR engine mount was developed to investigate the vibration isolation process. An engine mount test machine was designed to measure the displacement, relative velocity and damper force with respect to current supply to characterize the hysteresis behavior of the damper and as force tracking control of the MR engine mount.

  20. Developing a solar panel testing system

    Directory of Open Access Journals (Sweden)

    Árpád Rácz


    Full Text Available Solar energy is increasingly used togenerate electricity for individual households. There isa wide variety of solar panel technologies, whichshould be tested at an individual level during theirlifetime. In this paper, the development of a testingstation at the University of Debrecen is presented. Thetesting system can be used for research andeducational purposes and for in field applicationsequally well.

  1. Next Generation Drivetrain Development and Test Program

    Energy Technology Data Exchange (ETDEWEB)

    Keller, Jonathan; Erdman, Bill; Blodgett, Doug; Halse, Chris; Grider, Dave


    This presentation was given at the Wind Energy IQ conference in Bremen, Germany, November 30 through December 2, 2105. It focused on the next-generation drivetrain architecture and drivetrain technology development and testing (including gearbox and inverter software and medium-voltage inverter modules.

  2. Development of Thermal Shock Test Facility (United States)

    Lehmann, B.; Varewijck, G.; Dufour, J.-F.


    Thermal shock testing is performed to qualify materials and processes for use in space in accordance to ECSS- Q-70-04A. The Fast Thermal Vacuum facility (FTV) has been specially designed to allow testing from -100oC up to 550oC. This large temperature test range is achieved by having two separate temperature controlled compartments. The specimen is placed on a trolley, which moves from one compartment to the other. The challenge in development of the facility was the relatively large size of the compartments (600 mm x 600 mm x 400 mm) and the required vacuum level of p~1E-05 mbar. The FTV was successfully commissioned in September 2010. The presentation summarises the results of the commissioning, facility performance, test data and lessons learned.

  3. Development of an immunochromatographic strip test for rapid detection of melamine in raw milk, milk products, and animal feed (United States)

    A simple, rapid and sensitive immunogold chromatographic strip test based on a monoclonal antibody was developed for the detection of melamine (MEL) residues in raw milk, milk products and animal feed. The limit of detection was estimated to be 0.05 µg/mL in raw milk, since the detection test line ...

  4. Probability of a false-negative HIV antibody test result during the window period: a tool for pre- and post-test counselling. (United States)

    Taylor, Darlene; Durigon, Monica; Davis, Heather; Archibald, Chris; Konrad, Bernhard; Coombs, Daniel; Gilbert, Mark; Cook, Darrel; Krajden, Mel; Wong, Tom; Ogilvie, Gina


    Failure to understand the risk of false-negative HIV test results during the window period results in anxiety. Patients typically want accurate test results as soon as possible while clinicians prefer to wait until the probability of a false-negative is virtually nil. This review summarizes the median window periods for third-generation antibody and fourth-generation HIV tests and provides the probability of a false-negative result for various days post-exposure. Data were extracted from published seroconversion panels. A 10-day eclipse period was used to estimate days from infection to first detection of HIV RNA. Median (interquartile range) days to seroconversion were calculated and probabilities of a false-negative result at various time periods post-exposure are reported. The median (interquartile range) window period for third-generation tests was 22 days (19-25) and 18 days (16-24) for fourth-generation tests. The probability of a false-negative result is 0.01 at 80 days' post-exposure for third-generation tests and at 42 days for fourth-generation tests. The table of probabilities of falsely-negative HIV test results may be useful during pre- and post-test HIV counselling to inform co-decision making regarding the ideal time to test for HIV.

  5. Development and Characterization of a Monoclonal Antibody against Ochratoxin B and Its Application in ELISA

    Directory of Open Access Journals (Sweden)

    Alexandra H. Heussner


    Full Text Available A monoclonal antibody specific to ochratoxin B (OTB was employed for the development of an indirect competitive OTB-ELISA. The optimized OTB-ELISA resulted in a limit of detection (LOD for OTB of 3 µg/L (8 nM, a limit of quantification (LOQ of 3.7 µg/L (10 nM, and a 50% inhibitory concentration (IC50 of 150 nM. Due to very low cross-reactivity to OTA (2.7% and structurally related molecules (0%, this OTB-ELISA was found to be suitable to detect OTB with excellent precision in different matrices, i.e., beer, coffee and wine. Therefore, this OTB-ELISA will allow screening of OTB in food and feed products.

  6. Recent developments in dynamic testing of materials

    Directory of Open Access Journals (Sweden)

    Seidt J.D.


    Full Text Available Three new testing configurations that have been developed since the last DYMAT conference in 2009 are presented. The first is high strain rate testing of Kevlar cloth and Kevlar yarn in a tensile Split Hopkinson Bar (SHB apparatus. The Kevlar cloth/yarn is attached to the bars by specially designed adaptors that keep the impedance constant. In addition to determining the specimen’s stress and strain from the recorded waves in the bars the deformations are also measured with Digital Image Correlation (DIC. The second testing configuration is a high strain rate shear test for sheet metal. The experiment is done by using a flat notched specimen in a tensile SHB apparatus. The shear strain is measured using DIC within the notch and on the boundary. The third development is a compression apparatus for testing at intermediate strain rates ranging from 20 s−1 to 200 s−1. The apparatus is a combination of a hydraulic actuator and a compression SHB. The stress in the specimen is determined from the stress wave in a very long transmitter bar and the strain and strain rate is determined by using DIC. The results show clean stress strain curves (no ringing.

  7. A critical question for HIV vaccine development: Which antibodies to induce?


    Zolla-Pazner, Susan


    A vaccine against HIV-1 must prevent infection against genetically diverse virus strains. Two approaches are currently being pursued to elicit antibody-mediated protection: vaccines that induce potent and broadly reactive neutralizing antibodies (bnAbs) or vaccines that induce “conventional antibodies,” which are less potent and broadly neutralizing in comparison. Although bnAbs may provide the greatest level of protection, their structural and genetic characteristics make their elicitation t...

  8. Development Of Maneuvering Autopilot For Flight Tests (United States)

    Menon, P. K. A.; Walker, R. A.


    Report describes recent efforts to develop automatic control system operating under supervision of pilot and making airplane follow prescribed trajectories during flight tests. Report represents additional progress on this project. Gives background information on technology of control of test-flight trajectories; presents mathematical models of airframe, engine and command-augmentation system; focuses on mathematical modeling of maneuvers; addresses design of autopilots for maneuvers; discusses numerical simulation and evaluation of results of simulation of eight maneuvers under control of simulated autopilot; and presents summary and discussion of future work.

  9. Broadly neutralizing antibodies developed by an HIV-positive elite neutralizer exact a replication fitness cost on the contemporaneous virus. (United States)

    Sather, D Noah; Carbonetti, Sara; Kehayia, Jenny; Kraft, Zane; Mikell, Iliyana; Scheid, Johannes F; Klein, Florian; Stamatatos, Leonidas


    Approximately 1% of those infected with HIV-1 develop broad and potent serum cross-neutralizing antibody activities. It is unknown whether or not the development of such immune responses affects the replication of the contemporaneous autologous virus. Here, we defined a pathway of autologous viral escape from contemporaneous potent and broad serum neutralizing antibodies developed by an elite HIV-1-positive (HIV-1(+)) neutralizer. These antibodies potently neutralize diverse isolates from different clades and target primarily the CD4-binding site (CD4-BS) of the viral envelope glycoprotein. Viral escape required mutations in the viral envelope glycoprotein which limited the accessibility of the CD4-binding site to the autologous broadly neutralizing anti-CD4-BS antibodies but which allowed the virus to infect cells by utilizing CD4 receptors on their surface. The acquisition of neutralization resistance, however, resulted in reduced cell entry potential and slower viral replication kinetics. Our results indicate that in vivo escape from autologous broadly neutralizing antibodies exacts fitness costs to HIV-1.

  10. Development of gastric cancer in nonatrophic stomach with highly active inflammation identified by serum levels of pepsinogen and Helicobacter pylori antibody together with endoscopic rugal hyperplastic gastritis. (United States)

    Watanabe, Mika; Kato, Jun; Inoue, Izumi; Yoshimura, Noriko; Yoshida, Takeichi; Mukoubayashi, Chizu; Deguchi, Hisanobu; Enomoto, Shotaro; Ueda, Kazuki; Maekita, Takao; Iguchi, Mikitaka; Tamai, Hideyuki; Utsunomiya, Hirotoshi; Yamamichi, Nobutake; Fujishiro, Mitsuhiro; Iwane, Masataka; Tekeshita, Tatsuya; Mohara, Osamu; Ushijima, Toshikazu; Ichinose, Masao


    This study aimed to elucidate groups at high risk of developing cancer among patients with serologically identified Helicobacter pylori infection and nonatrophic stomach. Annual endoscopy was performed for a mean of 5.4 years in 496 asymptomatic middle-aged men who were H. pylori antibody-positive and pepsinogen (PG) test-negative. Subjects were stratified according to the activity of H. pylori-associated gastritis measured by serum levels of PG and H. pylori antibody, and/or by endoscopic findings of rugal hyperplastic gastritis (RHG), and cancer development was investigated. During the study period, seven cases of cancer developed in the cohort (incidence rate, 261/100,000 person-years), with 85.7% developing in the group showing a PGI/II ratio ≤ 3.0, reflecting active inflammation-based high PGII levels. Cancer incidence was significantly higher in this group (750/100,000 person-years) than in groups with less active gastritis. Furthermore, cancer incidence for this group was significantly higher in the subgroup with high H. pylori antibody titers than in the low-titer subgroup. Meanwhile, endoscopic findings revealed that 11.7% of subjects showed RHG reflecting localized highly active inflammation, and cancer risk was significantly higher in patients with RHG than in patients without. Combining the two serum tests and endoscopic examination for RHG allowed identification of subjects with more active gastritis and higher cancer risk. No cancer development was observed in these high-risk subjects after H. pylori eradication. Subjects with highly active gastritis identified by the two serological tests and endoscopic RHG constitute a group at high risk of cancer development with H. pylori-infected nonatrophic stomach.

  11. Effect of days in milk and milk yield on testing positive in milk antibody ELISA to Mycobacterium avium subsp. paratuberculosis in dairy cattle

    DEFF Research Database (Denmark)

    Nielsen, Søren Saxmose; Toft, Nils


    Milk samples are becoming more used as a diagnostic specimen for assessment of occurrence of antibodies to Mycobacterium avium subsp. paratuberculosis (MAP). This study assessed the effect of days in milk (DIM) and milk yield on testing positive in a commercial MAP specific milk antibody ELISA...... from the first couple of DIM should be excluded from MAP testing until further information on their significance is established. Milk yield also had a significant effect on odds of testing positive due to its diluting effect. Inclusion of milk yield in the interpretation of test results could improve...

  12. Application of GP5 Protein to Develop Monoclonal Antibody against Porcine Reproductive and Respiratory Syndrome Virus

    Institute of Scientific and Technical Information of China (English)

    Hong Tian; Yan Cheng; Jin-yang Wu; Jian-hui He; You-jun Shang; Xiang-tao Liu


    In this study,a panel of monoclonal antibodies (mAbs) against Porcine reproductive and respiratory syndrome virus(PRRSV),named as 8C9 and4B4,were produced by fusing SP2/0 myeloma cells and spleen cells of BALB/c mice immunized with the PRRSV (TCID50=5.5),screened by the indirect ELISA and subjected to several limiting dilutions.mAbs were then identified by biological characterization.Among the two fusion cell strains,8C9 belonged to the IgG1 subclass and 4B4 belonged to the IgG2a subclass.The titers in cell culture supernatant and abdomen liquor reached to 1:104and 1:105,respectively.The specificity test indicated that the two cells had specific reactions for the PRRSV and GP5 protein respectively,and no reaction with Classical swine fever virus (CSFV) or Swine vesicular disease virus (SVDV).The molecular weights of the heavy chain and light chain were about 45.0 kDa and 25.0 kDa,respectively.In neutralization activity tests,the results showed that the prepared mAb 4B4 can protect 50% of cells with no CPE in dilution up to 1:512,but mAB 8C9 has no neutralization activities to PRRSV.

  13. [Comparison of the indirect immunofluorescent (IFAT), ELISA test and the comercial Chagatek test for anti-Trypanosoma cruzi antibodies detection]. (United States)

    Enciso, Clara; Montilla, Marleny; Santacruz, María M; Nicholls, Rubén Santiago; Rodríguez, Adriana; Mercado, Marcela; Puerta, Concepción


    Chagas disease is a public health problem in Colombia, particularly in the eastern region. Because of human migration from rural areas to urban centers, the possibility of transfusional transmission becomes increasingly important. However the risk can be minimized by a careful screening of blood donors by means of serological tests. Colombian blood banks use comercial, foreign serological tests for screening for T. cruzi infection. The purpose of the current study was to compare the IFAT and ELISA tests (both use antigen obtained from Colombian strains) with the comercially available Chagatek tests. Sera of blood donors were classified in two groups on the basis of the IFAT: group I, 15 positive patients and group II, 14 negative patients. Sera from each group were tested by the ELISA and Chagatek tests. The ELISA test detected 100% of the patients as positive in group I and 7% (1/14) of patients as positive in group II. The Chagatek test detected 93% (14/15) of the patients as positive in group I and 50% (7/14) in group II. The kappa index for concordance between the ELISA and IFAT tests was 0.93 (95% C.I.: 0.80-1.00); between IFAT and Chagatek 0.43 (95% C.I.: 0.26-0.62), and between ELISA and Chagatek 0.49 (95% C.I.: 0.31-0.67). These results highlighted the importance of using autochtonous Colombian strains as antigens in screening tests for blood donors.

  14. Approach to a case of multiple irregular red cell antibodies in a liver transplant recipient: Need for developing competence

    Directory of Open Access Journals (Sweden)

    Ravi C Dara


    Full Text Available Liver transplant procedure acts as a challenge for transfusion services in terms of specialized blood components, serologic problems, and immunologic effects of transfusion. Red cell alloimmunization in patients awaiting a liver transplant complicate the process by undue delay or unavailability of compatible red blood cell units. Compatible blood units can be provided by well-equipped immunohematology laboratory, which has expertise in resolving these serological problems. This report illustrates resolution of a case with multiple alloantibodies using standard techniques, particularly rare antisera. Our case re-emphasizes the need for universal antibody screening in all patients as part of pretransfusion testing, which helps to identify atypical antibodies and plan for appropriate transfusion support well in time. We recommend that the centers, especially the ones that perform complex procedures like solid organ transplants and hematological transplants should have the necessary immunohematological reagents including rare antisera to resolve complex cases of multiple antibodies as illustrated in this case.

  15. Evaluation of Multiplex-Based Antibody Testing for Use in Large-Scale Surveillance for Yaws: a Comparative Study. (United States)

    Cooley, Gretchen M; Mitja, Oriol; Goodhew, Brook; Pillay, Allan; Lammie, Patrick J; Castro, Arnold; Moses, Penias; Chen, Cheng; Ye, Tun; Ballard, Ronald; Martin, Diana L


    WHO has targeted yaws for global eradication by 2020. The program goals are to interrupt the transmission in countries where yaws is endemic and to certify countries as yaws free where yaws was endemic in the past. No new rapid plasmin reagin (RPR) seroreactivity in young children is required for certification of elimination at a country level. We sought to evaluate whether antibody responses to specific treponemal antigens measured in a high-throughput multiplex bead array (MBA) assay differentiate past versus current infection and whether a nontreponemal lipoidal antigen test can be incorporated into the MBA. Serum and dried blood spot specimens collected for yaws surveillance projects in Ghana, Vanuatu, and Papua New Guinea (PNG) were run on MBA to measure antibodies against recombinant p17 (rp17) and treponemal membrane protein A (TmpA) treponemal antigens. Results were compared to standard treponemal laboratory (TPPA or TPHA [TPP(H)A]) and quantitative RPR test data. Of 589 specimens, 241 were TPP(H)A(+)/RPR(+), 88 were TPP(H)A(+)/RPR(-), 6 were TPP(H)A(-)/RPR(+), and 254 were negative for both tests. Compared to TPP(H)A, reactive concordance of rp17 was 93.7%, while reactive concordance of TmpA was only 81.9%. TmpA-specific reactivity showed good correlation with RPR titers (R(2) = 0.41; P RPR testing (cardiolipin) were not detected in the MBA. Our results suggest that TmpA can be used as a treponemal antigen marker for recent or active infection and potentially replace RPR in a high-throughput multiplex tool for large-scale yaws surveillance.

  16. Development of two murine antibodies against Neospora caninum using phage display technology and application on the detection of N. caninum.

    Directory of Open Access Journals (Sweden)

    Jinhua Dong

    Full Text Available Neosporosis, caused by an intracellular parasite, Neospora caninum, is an infectious disease primarily of cattle and dogs. It occurs worldwide and causes huge damages to dairy farms. In this study, we immunized mice with recombinant surface-associated protein 1 of N. caninum (rNcSAG1 and developed two novel monoclonal antibodies, A10 and H3, against NcSAG1 using phage-display technology. Both clones bound to purified rNcSAG1 and the half maximal inhibitory concentrations of A10 and H3 are 50 and 72 nM of rNcSAG1, respectively. In immunofluorescence assays, both A10 and H3 Fabs bound to N. caninum parasites. Direct detection of N. caninum parasites was developed firstly using an enzyme-linked immunosorbent assay (ELISA with A10 and H3. Binding of A10 and H3 antibodies to rNcSAG1 was also inhibited by some certain anti-N. caninum antibodies in the neosporosis-positive cattle sera, suggesting they might bind to the same epitopes of NcSAG1 with those anti-N. caninum antibodies of bovine. These antibodies were demonstrated to have a potential for monitoring the N. caninum parasites in a dairy farm, which may lead to protect livestock from parasite-infection.

  17. Development of Phage-Based Antibody Fragment Reagents for Affinity Enrichment of Bacterial Immunoglobulin G Binding Proteins. (United States)

    Säll, Anna; Sjöholm, Kristoffer; Waldemarson, Sofia; Happonen, Lotta; Karlsson, Christofer; Persson, Helena; Malmström, Johan


    Disease and death caused by bacterial infections are global health problems. Effective bacterial strategies are required to promote survival and proliferation within a human host, and it is important to explore how this adaption occurs. However, the detection and quantification of bacterial virulence factors in complex biological samples are technically demanding challenges. These can be addressed by combining targeted affinity enrichment of antibodies with the sensitivity of liquid chromatography-selected reaction monitoring mass spectrometry (LC-SRM MS). However, many virulence factors have evolved properties that make specific detection by conventional antibodies difficult. We here present an antibody format that is particularly well suited for detection and analysis of immunoglobulin G (IgG)-binding virulence factors. As proof of concept, we have generated single chain fragment variable (scFv) antibodies that specifically target the IgG-binding surface proteins M1 and H of Streptococcus pyogenes. The binding ability of the developed scFv is demonstrated against both recombinant soluble protein M1 and H as well as the intact surface proteins on a wild-type S. pyogenes strain. Additionally, the capacity of the developed scFv antibodies to enrich their target proteins from both simple and complex backgrounds, thereby allowing for detection and quantification with LC-SRM MS, was demonstrated. We have established a workflow that allows for affinity enrichment of bacterial virulence factors.

  18. Development of recombinant antibody technology for application in plant pathogen diagnosis

    NARCIS (Netherlands)

    Griep, R.A.


    This thesis describes the applicability of the novel phage display technique to select plant-pathogen-specific monoclonal antibodies (MAbs) from combinatorial antibody libraries. The retrieved MAbs are so specific that they can be used as diagnostic tools in sensitive immunoassays for the detection

  19. The World Health Organization Recommendations for Trachoma Surveillance, Experience in Nepal and Added Benefit of Testing for Antibodies to Chlamydia trachomatis pgp3 Protein: NESTS Study (United States)

    Zambrano, Andrea I.; Sharma, Shekhar; Crowley, Kathryn; Dize, Laura; Muñoz, Beatriz E.; Mishra, Sailesh K.; Rotondo, Lisa A.; Gaydos, Charlotte A.; West, Sheila K.


    Background The World Health Organization (WHO) now requires a second surveillance survey for trachoma after an impact assessment has found follicular trachoma (TF) <5% to determine if re-emergence has occurred. Using new WHO guidelines, we undertook surveillance surveys, and determined the prevalence of infection and antibody positivity, in two districts in Nepal. Methods 20 clusters were randomly selected within each district, 15 were randomly selected for antibody testing. In each cluster, we randomly selected 50 children ages 1–9 years and 100 adults ≥15 years. TF and trachomatous trichiasis (TT) were evaluated. Conjunctival swabs to test for chlamydial infection using GenXpert platform were obtained, and dried blood spots were collected to test for antibodies to Chlamydia Trachomatis pgp3 using the Luminex platform. Findings 3 cases of TF were found in the two districts, and one case of infection. Pgp3 antibody positivity was 2·4% (95% confidence interval: 1·4%, 3·7%), and did not increase with age (P = 0.24). No clustering of antibody positivity within communities was found. TT prevalence was <1/1,000 population. Interpretation The surveillance surveys, as proposed by WHO, showed no evidence for re-emergence of trachoma in two districts of Nepal. The low level and no significant increase by age in seroprevalence of antibodies to C trachomatis pgp3 antigen deserve further investigation as a marker of interruption of transmission. PMID:27654497

  20. Development and field application of a competitive enzyme-linked immunosorbent assay for detection of Newcastle disease virus antibodies in chickens and ducks. (United States)

    Phan, L V; Park, M-J; Kye, S-J; Kim, J-Y; Lee, H-S; Choi, K-S


    A competitive enzyme-linked immunosorbent assay (C-ELISA) using a baculovirus-expressed recombinant nucleocapsid protein antigen (rNDV-N) and an rNDV-N-specific monoclonal antibody (5B3) was developed for the detection of Newcastle disease virus (NDV) antibodies, and its diagnostic performance was evaluated. The specificity and sensitivity of the C-ELISA was found to be 98.4 and 98.9%, respectively, for chickens, and 98.2 and 97.9% for ducks. However, the C-ELISA showed weak cross-reaction with hyperimmune antisera to some other avian paramyxovirus serotypes. In all experimentally vaccinated chickens, seroconversion rates at 7 d postinoculation were 100 and 40% when measured by C-ELISA and hemagglutination inhibition (HI), respectively. In field trials, the C-ELISA showed positive results in 98.9% of HI-positive sera and 40.8% of HI-negative sera from NDV-vaccinated chickens (n = 705). In domestic ducks (n = 158) from NDV-positive duck farms (n = 8), the positive rates according to C-ELISA were significantly higher than those according to the HI test. At the same time, 98.1% of ducks (n = 209) from NDV-negative duck farms (n = 11) were also negative by C-ELISA. Our results indicate that C-ELISA could be a useful alternative to HI testing for detecting NDV antibodies in different avian species such as chickens and ducks.

  1. Summary receiver operating characteristics (SROC) and hierarchical SROC models for analysis of diagnostic test evaluations of antibody ELISAs for paratuberculosis. (United States)

    Toft, Nils; Nielsen, Søren S


    Critical, systematic reviews of available diagnostic test evaluations are a meticulous approach to synthesize evidence about a diagnostic test. However, often the review finds that data quality is poor due to deficiencies in design and reporting of the test evaluations and formal statistical comparisons are discouraged. Even when only simple summary measures are appropriate, the strong correlation between sensitivity and specificity and their dependence on differences in diagnostic threshold across studies, creates the need for tools to summarise properties of the diagnostic test under investigation. This study presents summary receiver operating characteristics (SROC) analysis as a means to synthesize information from diagnostic test evaluation studies. Using data from a review of diagnostic tests for ante mortem diagnosis of paratuberculosis as an illustration, SROC and hierarchical SROC (HSROC) analysis were used to estimate overall diagnostic accuracies of antibody ELISAs for bovine paratuberculosis while accounting for covariates: the target condition (infectious or infected) used in the test evaluation (one for the evaluation of Se and one for Sp); and the type of test (serum vs. milk). The methods gave comparable results (regarding the estimated diagnostic log odds ratio), considering the small sample size and the quality of data. The SROC analysis found a difference in the performance of tests when the target condition for evaluation of Se was infected rather than infectious, suggesting that ELISAs are not suitable for detecting infected cattle. However, the SROC model does not take differences in sample size between study units into account, whereas the HSROC allows for both between and within study variation. Considering the small sample size, more credibility should be given to the results of the HSROC. For both methods the area under the (H)SROC curve was calculated and results were comparable. The conclusion is that while the SROC is simpler and easier

  2. Poor sensitivity of rapid tests for the detection of antibodies to the hepatitis B virus: implications for field studies (United States)

    Cruz, Helena Medina; Scalioni, Leticia de Paula; de Paula, Vanessa Salete; Miguel, Juliana Custódio; do Ó, Kycia Maria Rodrigues; Milagres, Flavio Augusto Pádua; Cruz, Marcelo Santos; Bastos, Francisco Inácio; Flores, Priscila Pollo; Leal, Erotildes; Motta-Castro, Ana Rita Coimbra; Lewis-Ximenez, Lia Laura; Lampe, Elisabeth; Villar, Livia Melo


    Rapid tests (RTs) can be used as an alternative method for the conventional diagnosis of hepatitis B virus (HBV). This study aims to evaluate antibodies to HBsAg (anti-HBs) and antibodies to HBeAg (anti-HBe) RTs under different Brazilian settings. The following three groups were included: GI: viral hepatitis outpatient services; GII: low resource areas; and GIII: crack users and beauticians. Imuno-rápido anti-HBsAg™ and Imuno-rápido anti-HBeAg™ RTs were evaluated and showed specificities greater than 95% in all groups. The sensitivity values to anti-HBs were 50.38%, 51.05% and 46.73% and the sensitivity values to anti-HBe were 76.99%, 10.34% and 11.76% in the GI, GII and GIII groups, respectively. The assays had a low sensitivity and high specificity, which indicated their use for screening in regions endemic for HBV. PMID:28146158

  3. Immunofluorescent Antibody Test (IFAT for Trypanosoma cruzi in dogs from urban and rural areas of Pelotas, RS

    Directory of Open Access Journals (Sweden)

    Charlene Nascimento dos Santos


    Full Text Available Chagas disease (CD is a zoonosis with the protozoan Trypanosoma cruzi as the causative agent. Dogs are considered the main domestic reservoir for T. cruzi in most Latin American countries and in some areas of the United States. In southern Brazil, despite being an endemic area of the disease, the prevalence in dogs is still unknown. This study aimed to evaluate the frequency of T. cruzi antibodies in dogs from urban and rural areas of Pelotas, RS, Brazil. A total of 227 canine sera were used for serological tests, of which 99 were from urban areas and 128 were from rural areas of Pelotas. Information regarding the environment and the possible risk factors (origin, rural contact, age, breed, confinement and gender to which the dogs were exposed were recorded. Indirect immunofluorescence was used to assess the presence of specific immunoglobulins (IgG anti-T. cruzi in the serum of dogs. Of the 227 sera analyzed, 81 (35.7% exhibited anti-T. cruzi, which represented 34.3% of the dogs from the urban area and 36.7% of the dogs from the rural area. Among the variables analyzed, rural contact and male gender showed an association with seropositivity for T. cruzi. The detection of T. cruzi antibodies in the serum of these dogs emphasizes the need to study trypanosomiasis in this important domestic reservoir of Chagas disease.

  4. Detection of rainbow trout antibodies against viral haemorrhagic septicaemia virus (VHSV) by neutralisation test is highly dependent on the virus isolate used

    DEFF Research Database (Denmark)

    Fregeneda-Grandes, J.M.; Olesen, Niels Jørgen


    Three serological tests, enzyme linked immunosorbent assay (ELISA), 50 % plaque neutralisation test (50%PNT) and Western blotting (WB), were used to detect antibodies against viral haemorrhagic septicaerma virus (VHSV) in 50 rainbow trout broodstock from a rainbow trout farm endemically infected ...... VHSV. When the sera were examined for the presence of VHSV antibodies by ELISA or WB, 61 % were found to be positive. When conducting WB analysis, the viral glycoprotein was the protein most frequently recognized, followed by the viral nucleoprotein.......Three serological tests, enzyme linked immunosorbent assay (ELISA), 50 % plaque neutralisation test (50%PNT) and Western blotting (WB), were used to detect antibodies against viral haemorrhagic septicaerma virus (VHSV) in 50 rainbow trout broodstock from a rainbow trout farm endemically infected...

  5. Development of single chain variable fragment (scFv) antibodies against surface proteins of 'Ca. Liberibacter asiaticus'. (United States)

    Yuan, Qing; Jordan, Ramon; Brlansky, Ronald H; Minenkova, Olga; Hartung, John


    'Candidatus Liberibacter asiaticus' is the causal agent of citrus huanglongbing, the most serious disease of citrus worldwide. We have developed and applied immunization and affinity screening methods to develop a primary library of recombinant single chain variable fragment (scFv) antibodies in an M13 vector, pKM19. The antibody population is enriched for antibodies that bind antigens of 'Ca. Liberibacter asiaticus'. The primary library has more than 10(7) unique antibodies and the genes that encode them. We have screened this library for antibodies that bind to specifically-chosen proteins that are present on the surface of 'Ca. Liberibacter asiaticus'. These proteins were used as targets for affinity-based selection of scFvs that bind to the major outer membrane protein, OmpA; the polysaccharide capsule protein KpsF; a protein component of the type IV pilus (CapF); and, two flagellar proteins FlhA and FlgI. These scFvs have been used in ELISA and dot blot assays against purified protein antigens and 'Ca. Liberibacter asiaticus' infected plant extracts. We have also recloned many of these scFvs into a plasmid expression vector designed for the production of scFvs. Screening of these scFvs was more efficient when phage-bound, rather than soluble scFvs, were used. We have demonstrated a technology to produce antibodies at will and against any protein target encoded by 'Ca. Liberibacter asiaticus'. Applications could include advanced diagnostic methods for huanglongbing and the development of immune labeling reagents for in planta applications.

  6. The development of an enzyme-linked immunosorbent assay for Trypanosoma vivax antibodies and its use in epidemiological surveys

    Directory of Open Access Journals (Sweden)

    Claudio R Madruga


    Full Text Available There are data indicating that the distribution of Trypanosoma vivax in the Brazilian territory is expanding with potential to reach other areas, where the vectors are present. The detection of anti-trypanosomal antibodies in serum provides important information of the trypanosomal status in cattle herds. For this reason, an enzyme-linked immunosorbent assay (Tv-ELISA-Ab with crude antigen from one Brazilian isolate of T. vivax was developed and evaluated. The sensitivity and specificity were respectively 97.6 and 96.9%. In the evaluation of cross-reactions, three calves inoculated with T. evansi trypimastigotes blood forms showed optical densities (OD under the cut-off during the whole experimental period, except one at 45 days post-inoculation. With relation to Babesia bovis, B. bigemina, and Anaplasma marginale, which are endemic hemoparasites in the studied area, the cross-reactions were shown to be 5.7, 5.3, and 1.1%, respectively. The first serological survey of Pantanal and state of Pará showed that T. vivax is widespread, although regions within both areas had significantly different prevalences. Therefore, this Tv-ELISA-Ab may be a more appropriate test for epidemiological studies in developing countries because the diagnostic laboratories in most countries may be able to perform an ELISA, which is not true for polymerase chain reaction.

  7. Development of novel monoclonal antibodies directed against catechins for investigation of antibacterial mechanism of catechins. (United States)

    Miyamoto, Takahisa; Zhang, Xiaoguang; Ueyama, Yuuki; Apisada, Kitichalermkiat; Nakayama, Motokazu; Suzuki, Yasuto; Ozawa, Tadahiro; Mitani, Asako; Shigemune, Naofumi; Shimatani, Kanami; Yui, Koji; Honjoh, Ken-Ichi


    Catechins are major polyphenolic compounds of green tea. To investigate mechanism for antibacterial action of catechins, 11 monoclonal antibodies (MAbs) were raised against a 3-succinyl-epicatechin (EC)-keyhole limpet hemocyanin (KLH) conjugate. Amino acid sequences of variable regions determined for MAbs b-1058, b-1565, and b-2106 confirmed their innovative character. MAb b-1058 strongly interacted with its target substances in the following order of magnitude: theaflavin-3,3'-di-O-gallate (TFDG)>theaflavin-3-O-gallate (TF3G)≥theaflavin-3'-O-gallate (TF3'G)>gallocatechin gallate (GCg)>penta-O-galloyl-β-d-glucose (PGG)>epigallocatechin gallate (EGCg), as determined using surface plasmon resonance (SPR) on MAb-immobilized sensor chips. The affinity profiles of MAbs b-1058 and b-2106 to the various polyphenols tested suggested that flavan skeletons with both carbonyl oxygen and hydroxyl groups are important for this interaction to take place. S. aureus cells treated with EGCg showed green fluorescence around the cells after incubation with FITC-labeled MAb b-1058. The fluorescence intensity increased with increasing concentrations of EGCg. These MAbs are effective to investigate antibacterial mechanism of catechins and theaflavins.

  8. Development of a streptavidin-anti-carcinoembryonic antigen antibody, radiolabeled biotin pretargeting method for radioimmunotherapy of colorectal cancer. Reagent development. (United States)

    Karacay, H; Sharkey, R M; Govindan, S V; McBride, W J; Goldenberg, D M; Hansen, H J; Griffiths, G L


    With pretargeting, radioisotope delivery to tumor is decoupled from the long antibody localization process, and this can increase tumor:blood ratios dramatically. Several reagents were prepared for each step of a "two-step" pretargeting method, and their properties were investigated. For pretargeting tumor, streptavidin-monoclonal antibody (StAv-mab) conjugates were prepared by cross-linking sulfo-SMCC-derivatized streptavidin to a free thiol (SH) group on MN-14 [a high-affinity anti-carcinoembryonic antigen (CEA) mab]. Thiolated mabs were generated either by reaction of 2-iminothiolane (2-IT) with mab lysine residues or by reduction of mab disulfide bonds with (2-mercaptoethyl)amine (MEA). Both procedures gave protein-protein conjugates isolated in relatively low yields (20-25%) after preparative size-exclusion (SE) chromatography purification with conservative peak collection. Both StAv-MN-14 conjugates retained their ability to bind to CEA, to an anti-idiotypic antibody to MN-14 (WI2), and to biotin, as demonstrated by SE-HPLC. Two clearing agents, WI2 mab and a biotin-human serum albumin (biotin-HSA) conjugate, were developed to remove excess circulating StAv-MN-14 conjugates in animals. Both clearing proteins were also modified with galactose residues, introduced using an activated thioimidate derivative, to produce clearing agents which would clear rapidly and clear primary mab rapidly. At least 14 galactose residues on WI2 were required to reduce blood levels to 5.9 +/- 0.7% ID/g in 1 h. Faster blood clearance (0.7 +/- 0.2% ID/g) was observed in 1 h using 44 galactose units per WI2. For the delivery of radioisotope to tumor, several biotinylated conjugates consisting of biotin, a linker, and a chelate were prepared. Conjugates showed good in vitro and in vivo stability when D-amino acid peptides were used as linkers, biotin-peptide-DOTA-indium-111 had a slightly longer blood circulation time (0.09 +/- 0.02% ID/g in 1 h) than biotin-peptide-DTPA-indium-111 (0

  9. Comparative study of antibody levels developed by vaccination against polio virus in population after vaccine type alteration. (United States)

    Farkas, Ágnes; Magyar, Nóra; Szomor, Katalin N; Takács, Mária


    During clinical trials, samples from Hungarian patients of different age groups were tested for antibodies against all 3 serotypes of poliovirus, a member of Picornaviridae family. During the virus neutralization serological test, blood samples were titrated using permanent virus concentration. Based on the cythopathic effect observed under a light microscope, the antibody level of the patient was assessed. The 100 people examined were classified into 5 groups based on age and type of original vaccine: I. Newborns, no vaccination given; II. Immunosuppressed patients; III. Born before 1986, received only OPV vaccine; IV. Born between 1992-2005, received a combination of OPV and IPV vaccines; V. Born after 2006, received only IPV vaccine. Results show that vaccination coverage meets all the criteria. None of the immunized persons was seronegative to all three polioviruses. Both IPV and OPV vaccines are effective against poliovirus. Blood samples from newborn babies with no immunization were also examined. Results show that most newborns have maternal antibodies in their blood. Results of group II show that immunosuppression does not have a negative influence on blood antibody levels against polioviruses. In spite of the low number of samples, our results show that seroconversion after immunization in the Hungarian population is adequate. For more accurate results about vaccination coverage in the population, further trials would be necessary.

  10. Biotechnology and genetic engineering in the new drug development. Part II. Monoclonal antibodies, modern vaccines and gene therapy. (United States)

    Stryjewska, Agnieszka; Kiepura, Katarzyna; Librowski, Tadeusz; Lochyński, Stanisław


    Monoclonal antibodies, modern vaccines and gene therapy have become a major field in modern biotechnology, especially in the area of human health and fascinating developments achieved in the past decades are impressive examples of an interdisciplinary interplay between medicine, biology and engineering. Among the classical products from cells one can find viral vaccines, monoclonal antibodies, and interferons, as well as recombinant therapeutic proteins. Gene therapy opens up challenging new areas. In this review, a definitions of these processes are given and fields of application and products, as well as the future prospects, are discussed.

  11. Development of Double Antibody Sandwich ELISA for Detection of Duck or Goose Flavivirus

    Institute of Scientific and Technical Information of China (English)

    NIU Hui-min; LI Xiang-rui; LI Yin; HUANG Xin-mei; HAN Kai-kai; LIU Yu-zhuo; ZHAO Dong-min; ZHANG Jing-feng; LIU Fei; LI Tong-tong; ZHOU Xiao-bo


    In order to establish double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) for detection of duck or goose flavivirus, polyclonal antibody against the flavivirus strain JS804 in geese and monoclonal antibody against the E protein of flavivirus strain JS804 in geese were used as the capture antibody and detection antibody, respectively. The optimal dilution of the capture antibody and detecting antibody capable of detecting the flavivirus strain JS804 in geese were 1:3 200 and 1:160 in the check-board titration, respectively. The reaction time of sample was 1 h, and the optimal working dilution of HRP-labeled goat-anti-mouse IgG was 1:10 000. The positive standard value was 0.247 (OD450 nm). The geese flavivirus could be detected at a minimal concentration of 1.875μg mL-1. The ELISA had no cross-reaction with Newcastle disease virus (NDV), Avian influenza virus (AIV), Infectious bronchitis virus (IBV), Infectious bursal disease virus (IBDV), Duck hepatitis virus (DHV), and Gosling plague virus (GPV). Twenty clinical samples were detected by the DAS-ELISA and RT-PCR respectively, with the agreement rate of 75%. The results revealed that the DAS-ELISA possessed favorable specificity and higher sensitivity, indicating a suitable method for rapid detection of the duck or goose flavivirus.

  12. A multilaboratory evaluation of a commercial enzyme-linked immunosorbent assay test for the detection of antibodies against Mycobacterium avium subsp. paratuberculosis in cattle. (United States)

    Dargatz, David A; Byrum, Beverly A; Collins, Michael T; Goyal, Sagar M; Hietala, Sharon K; Jacobson, Richard H; Kopral, Christine A; Martin, Barbara M; McCluskey, Brian J; Tewari, Deepanker


    results with kit lot being a primary contributor. Similar data for other ELISA tests for antibodies to M. avium subsp. paratuberculosis or other antigens also should be developed.

  13. Penetration Testing Curriculum Development in Practice

    Directory of Open Access Journals (Sweden)

    Chengcheng Li


    report for the management team to aid in strengthening the system, never to cause any real damages. This paper introduces the development of a penetration testing curriculum as a core class in an undergraduate cybersecurity track in Information Technology. The teaching modules are developed based on the professional penetration testing life cycle. The concepts taught in the class are enforced by hands-on lab exercises. This paper also shares the resources that are available to institutions looking for teaching materials and grant opportunities to support efforts when creating a similar curriculum in cybersecurity.

  14. Development of an enzyme-linked immunosorbent assay for the detection of isomiroestrol, an identical marker, in White Kwao Krua using a monoclonal antibody. (United States)

    Kitisripanya, Tharita; Jutathis, Kamonthip; Inyai, Chadathorn; Komaikul, Jukrapun; Udomsin, Orapin; Tanaka, Hiroyuki; Putalun, Waraporn


    Pueraria candollei var. mirifica or White Kwao Krua (WKK) is a phytoestrogen-rich plant widely used among women to improve climacteric symptoms. Additionally, the tuberous roots of this plant have been added as an active ingredient for skin rejuvenation and breast enlargement effects in various functional foods. However, most of the products on the market containing WKK have not been sufficiently standardized with respect to the active compound or identical marker. To control the quality of these plant materials, an enzyme-linked immunosorbent assay (ELISA) using anti-isomiroestrol antibodies was established for the determination of isomiroestrol, an identical marker in WKK. Polyclonal and monoclonal antibodies against isomiroestrol were generated and their specificity characterized in this study. Monoclonal antibody 12C1 showed higher specificity to isomiroestrol and was thus selected to develop the ELISA. Based on the validation analysis and the tested performance of the developed ELISA in variably sourced WKK samples, the assay can provide an alternative approach that is reliable and highly sensitive for the quantitative analysis of isomiroestrol in plant.

  15. Seroprevalence of Neospora caninum and Toxoplasma gondii antibodies in white tailed deer (odocoileus virginianus) from Iowa and Minnesota using four serologic tests (United States)

    The white-tailed deer (Odocoileus virginianus) is considered one of the most important wildlife reservoir of Neospora caninum and Toxoplasma gondii in the US. Sera from white-tailed deer from Minnesota and Iowa were tested for antibodies to N. caninum by four serologic tests including the indi...

  16. Development and characterization of new polyclonal antibodies specific for three polychlorinated biphenyls

    Institute of Scientific and Technical Information of China (English)

    Han Yu Chen; Hui Sheng Zhuang; Chun Zhou


    Three polychlorinated biphenyls(PCBs)congeners and their corresponding haptens bearing four carbon length carboxylic groups that can be linked to a protein for raising antibodies were synthesized.The three resultant immunogens were fabricated and used to stimulate immune responses in rabbits to survey the characteristics of the haptens.Three of the resultant polyclonal antibodies(Pabs)were obtained.The antiserum exhibited relatively high antibody titres(1:32-64)in double agar diffusion.◎2008 Hui Sheng Zhuang.Published by Elsevier B.V.on behalf of Chinese Chemical Society.All rights reserved.

  17. Development and Testing of Active Groundwater Samplers

    DEFF Research Database (Denmark)

    Nilsson, Bertel; Jakobsen, Rasmus; Andersen, Lars Jørgen


    on numerical modelling and controlled laboratory experiments. Active groundwater sampling techniques can be used for remedial pumping optimization and in obtaining hydraulic data and represent a fast operational and reliable sampling tool, also under heterogeneous and low permeability conditions.......Active groundwater sampling techniques are methods where the aquifer is flushed by pumping. The methods developed and tested represent non-dedicated methods for use in existing water wells. This paper describes two different sampling techniques: the Separation Pumping Technique (SP) and the Packer...

  18. Serologic test systems development. Progress report, July 1, 1976--September 30, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, G.C.; Clinard, E.H.; Bartlett, M.L.; Petersen, P.M.; Sanders, W.M.; Payne, R.J.; Martinez, E.


    Work has continued on the development and application of the Enzyme-Labeled Antibody (ELA) test to the USDA needs. Results on trichinosis, brucellosis, and staphylococcal enterotoxin A detection are very encouraging. A field test for trichinosis detection is being worked out in cooperation with Food Safety and Quality Service personnel. Work is in progress with the Technicon Instrument Corporation to develop a modification of their equipment to automatically process samples by the ELA procedure. An automated ELA readout instrument for 96-well trays has been completed and is being checked out.


    Eremkin, A V; Elagin, G D; Petchenkin, D V; Fomenkov, O O; Bogatcheva, N V; Kitmanov, A A; Kuklina, G V; Tikhvinskaya, O V


    The immune enzyme and immunochromatographic test-systems for detecting tularemia agent were developed on the basis of selected set of monoclonal antibodies having immunochemical activity to antigens Francisella tularensis. The evaluation of sensitivity and specificity of developed test-systems demonstrated that samples provided detection of strains of F. tularensis in concentration from 5.0 x 105 mkxcm-3 to 1.0 x 106 mkxcm-3 and gave no false positive results in analysis of heterologous microorganisms in concentration of 1.0 x 108 mkxcm-3.

  20. Cluster Development Test 2: An Assessment of a Failed Test (United States)

    Machin, Ricardo A.; Evans, Carol T.


    On 31 July 2008 the National Aeronautics and Space Administration Crew Exploration Vehicle Parachute Assembly System team conducted the final planned cluster test of the first generation parachute recovery system design. The two primary test objectives were to demonstrate the operation of the complete parachute system deployed from a full scale capsule simulator and to demonstrate the test technique of separating the capsule simulator from the Low Velocity Air Drop pallet used to extract the test article from a United States Air Force C-17 aircraft. The capsule simulator was the Parachute Test Vehicle with an accurate heat shield outer mold line and forward bay compartment of the Crew Exploration Vehicle Command Module. The Parachute Test Vehicle separated cleanly from the pallet following extraction, but failed to reach test conditions resulting in the failure of the test and the loss of the test assets. No personnel were injured. This paper will discuss the design of the test and the findings of the team that investigated the test, including a discussion of what were determined to be the root causes of the failure.

  1. Strategies for developing design spaces for viral clearance by anion exchange chromatography during monoclonal antibody production. (United States)

    Strauss, Daniel M; Cano, Tony; Cai, Nick; Delucchi, Heather; Plancarte, Magdalena; Coleman, Daniel; Blank, Gregory S; Chen, Qi; Yang, Bin


    The quality-by-design (QbD) regulatory initiative promotes the development of process design spaces describing the multidimensional effects and interactions of process variables on critical quality attributes of therapeutic products. However, because of the complex nature of production processes, strategies must be devised to provide for design space development with reasonable allocation of resources while maintaining highly dependable results. Here, we discuss strategies for the determination of design spaces for viral clearance by anion exchange chromatography (AEX) during purification of monoclonal antibodies. We developed a risk assessment for AEX using a formalized method and applying previous knowledge of the effects of certain variables and the mechanism of action for virus removal by this process. We then use design-of-experiments (DOE) concepts to perform a highly fractionated factorial experiment and show that varying many process parameters simultaneously over wide ranges does not affect the ability of the AEX process to remove endogenous retrovirus-like particles from CHO-cell derived feedstocks. Finally, we performed a full factorial design and observed that a high degree of viral clearance was obtained for three different model viruses when the most significant process parameters were varied over ranges relevant to typical manufacturing processes. These experiments indicate the robust nature of viral clearance by the AEX process as well as the design space where removal of viral impurities and contaminants can be assured. In addition, the concepts and methodology presented here provides a general approach for the development of design spaces to assure that quality of biotherapeutic products is maintained.

  2. Evaluation of an egg yolk enzyme-linked immunosorbent assay antibody test and its use to assess the prevalence of Mycoplasma gallisepticum infection in laying hens in Italy

    Directory of Open Access Journals (Sweden)

    Marco Tamba


    Full Text Available The prevalence of Mycoplasma gallisepticum infection in commercial layers was established by the presence of antibodies in eggs. Saline-extracted yolks were used with a commercial enzyme-linked immunosorbent assay kit. For the prevalence study, yolks from 30 eggs were obtained from each of 66 flocks coming from 36 layer farms. The prevalence of egg antibodies to Mycoplasma gallisepticum was 33.3% in single-age farms and 77.8% in multi-age farms. In 27 flocks, antibody titers were compared with results obtained from blood samples taken in the same flock and in the same period and analyzed with the same kit. This study has confirmed that egg yolk enzyme-linked immunosorbent assay antibody test is a suitable and practical approach for assessing the flock prevalence of Mycoplasma gallisepticum infection in layer hens.

  3. Evaluation of a new latex agglutination test for detection of streptolysin O antibodies.


    Gerber, M. A.; Caparas, L S; Randolph, M F


    Acute- and convalescent-phase serum specimens were collected from 50 patients with group A streptococcal pharyngitis. The anti-streptolysin O (ASO) titer for each serum specimen was determined by using both the standard neutralization assay and the latex agglutination (LA) test (Rheumagen ASO; Biokit Inc., New Britain, Conn.). When the ASO titers derived by the two methods were compared, the correlation coefficient was 0.93. When the ability of the LA test to demonstrate a significant ASO tit...

  4. Hacking into the granuloma: could antibody antibiotic conjugates be developed for TB? (United States)

    Ekins, Sean


    Alternatives to small molecule or vaccine approaches to treating tuberculosis are rarely discussed. Attacking Mycobacterium tuberculosis in the granuloma represents a challenge. It is proposed that the conjugation of small molecules onto a monoclonal antibody that recognizes macrophage or lymphocytes cell surface receptors, might be a way to target the bacteria in the granuloma. This antibody drug conjugate approach is currently being used in 2 FDA approved targeted cancer therapies. The pros and cons of this proposal for further research are discussed.

  5. Antibodies Against Infliximab Are Associated with De Novo Development of Antibodies to Adalimumab and Therapeutic Failure in Infliximab-to-Adalimumab Switchers with IBD

    DEFF Research Database (Denmark)

    Frederiksen, Madeline Therese; Ainsworth, Mark Andrew; Brynskov, Jørn


    BACKGROUND: A notable proportion of patients with inflammatory bowel disease (IBD) are switched from infliximab (IFX) to adalimumab (ADL). We investigated if immunogenicity of IFX influenced immunogenicity and clinical outcomes of later ADL therapy. METHODS: Single-center cohort study including all...... patients with IBD assessed for antibodies (Abs) against IFX or ADL. RESULTS: Anti-IFX Abs were evaluated in 187 patients treated with IFX as first line anti-TNF agent. Approximately, half (49%) were positive. Detected anti-IFX Abs had functional capacity as judged by a median IFX concentration below limit...... to develop de novo anti-ADL Abs, which may result in therapeutic failure. Assessment of ADL immunogenicity in anti-IFX Ab-positive switchers is required to ensure optimal interventions at inadequate treatment responses and to avoid inappropriate ADL intensification regimens....

  6. Quality Control System for Beer Developed with Monoclonal Antibodies Specific to Barley Lipid Transfer Protein

    Directory of Open Access Journals (Sweden)

    Yukie Murakami-Yamaguchi


    Full Text Available Non-specific lipid transfer protein (LTP in barley grain reacted with the IgE in sera drawn from food allergy patients. A sandwich-type of enzyme-linked immunosorbent assay (ELISA was developed with mouse monoclonal antibodies raised against LTP purified with barley flour. This ELISA showed a practical working range of 0.3–3 ng/mL and no cross-reactivity with wheat, adlay and rye. Using this ELISA, LTP was determined in several types of barley-foods, including fermented foods such as malt vinegar, barley-malt miso and beer. LTP content in beer of the same kind was approximately constant, even if manufacturing factory and production days were different. Not only as a factor of foam formation and stability but also as an allergen, controlling and monitoring of LTP in beer should be considered. Taken together, our LTP-detecting ELISA can be proposed as an appropriate system for the quality control of beer.

  7. Evaluation of a safranin-O-stained antigen microagglutination test for francisella tularensis antibodies.



    A microagglutination test for Francisella tularensis, with 0.025-ml amounts of diluted sera and 0.025-ml amounts of safranin-O-stained antigen in U-bottom microtitration plates, was compared with a tube agglutination test by using 137 sera. There was 86.3% agreement (+/- 1 dilution variation) between the microagglutination results and the tube agglutination results for sera with tube agglutination titers of greater than or equal to 20. There was 100% agreement (+/- 1 dilution variation) for s...

  8. Development and validation of an enzyme-linked immunosorbent assay for antibodies against Mycobacterium bovis in european wild boar

    Directory of Open Access Journals (Sweden)

    Gortázar Christian


    Full Text Available Abstract Background Bovine tuberculosis (bTB remains a significant problem in some parts of Spain largely because of contacts between cattle and wildlife reservoirs in extensive grazing systems. European Wild boar (Sus scrofa is one of the species involved in the transmission of the disease to other species. Fast and simple detection methods would be critical for assessing infection prevalence, study the mechanisms of pathogen transmission and monitoring the effects of TB control measures. Results An enzyme-linked immunosorbent assay (ELISA to detect antibodies against Mycobacterium bovis in wild boar serum was developed and validated on 185 sera from TB positive and negative wild boar. Based on antigen inoculation of captive animals as well as tuberculosis compatible lesions, culture results and molecular analysis of hunted individuals, animals were allocated into two groups: tuberculosis positive group and tuberculosis negative group. After optimization of the positive to negative ratio using different combinations of serum dilutions and conjugate concentrations, the test yielded a sensitivity of 72.60% and a specificity of 96.43% for the best cut-off. Conclusion Although some negative group animals showed an ELISA positive reaction (

  9. Development of a simple and quick immunochromatography method for detection of anti-HPV-16/-18 antibodies (United States)

    Endo, Fumiko; Tabata, Tsutomu; Sadato, Daichi; Kawamura, Machiko; Ando, Noriyuki; Ukaji, Masako; Kobayashi, Kaoru; Kobayashi, Yukuharu; Ikeda, Tomoaki; Shibasaki, Futoshi


    Immunochromatography (IC) is widely used to detect target molecules in biological fluids. Since this method can be performed without a special technique or device, IC is a convenient way to assess the existence of antibodies or pathogens such as viruses and bacteria, simply and quickly. In this study, we established an IC method to detect serum antibodies against oncogenic human papillomavirus (HPV)-16 and HPV-18 L1 proteins using recombinant L1 proteins produced by silkworms as antigens. Infection of oncogenic HPVs is a major risk factor of cervical cancer, which is one of the most common cancers in women worldwide. We first measured blood sera of two groups by magnetic beads enzyme-linked immunosorbent assay (MB-ELISA). For the first group, sera were collected prospectively from young women who planned to receive HPV vaccination. The second group consisted of children under 20 years of age, non-vaccinated healthy women, vaccinated healthy women, dysplasia, cervical intraepithelial neoplasia III, and cervical cancer patients. We confirmed that standard vaccination doses significantly increased serum HPV antibody concentrations, and the level was sustained at least more than 30 months after vaccination. In contrast, an increase in antibody concentration was not observed in patients with precancerous cervical changes and cervical cancer. We next measured the samples in both groups using the IC method we originally developed, and found that the measurement values of IC highly correlated with those of MB-ELISA. The simple and quick IC method would be a useful tool for rapid monitoring of L1 specific antibody levels in a non-laboratory environment. With less than one drop of serum, our IC can easily detect serum HPV-16/-18 antibodies within 15 minutes, without the need for electronic devices or techniques. PMID:28158224

  10. Mollusc reproductive toxicity tests - Development and validation of test guidelines

    DEFF Research Database (Denmark)

    Ducrot, Virginie; Holbech, Henrik; Kinnberg, Karin Lund

    for P. antipodarum consisted in a comparative 28-day study between four laboratories and with two test substances: cadmium (Cd) and bisphenol A (BPA). For L. stagnalis, pre-validation consisted in a comparative 56-day study between six laboratories and with two test substances: Cd and tributyltin (TBT...

  11. New cell line development for antibody-producing Chinese hamster ovary cells using split green fluorescent protein

    Directory of Open Access Journals (Sweden)

    Kim Yeon-Gu


    Full Text Available Abstract Background The establishment of high producer is an important issue in Chinese hamster ovary (CHO cell culture considering increased heterogeneity by the random integration of a transfected foreign gene and the altered position of the integrated gene. Fluorescence-activated cell sorting (FACS-based cell line development is an efficient strategy for the selection of CHO cells in high therapeutic protein production. Results An internal ribosome entry site (IRES was introduced for using two green fluorescence protein (GFP fragments as a reporter to both antibody chains, the heavy chain and the light chain. The cells co-transfected with two GFP fragments showed the emission of green fluorescence by the reconstitution of split GFP. The FACS-sorted pool with GFP expression had a higher specific antibody productivity (qAb than that of the unsorted pool. The qAb was highly correlated with the fluorescence intensity with a high correlation coefficient, evidenced from the analysis of median GFP and qAb in individual selected clones. Conclusions This study proved that the fragment complementation for split GFP could be an efficient indication for antibody production on the basis of high correlation of qAb with reconstitution of GFP. Taken together, we developed an efficient FACS-based screening method for high antibody-producing CHO cells with the benefits of the split GFP system.

  12. Selection of antibodies from synthetic antibody libraries. (United States)

    Harel Inbar, Noa; Benhar, Itai


    More than 2 dozen years had passed since the field of antibody engineering was established, with the first reports of bacterial [1-3] and mammalian cells [4] expression of recombinant antibody fragments, and in that time a lot of effort was dedicated to the development of efficient technological means, intended to assist in the creation of therapeutic monoclonal antibodies (mAbs). Research focus was given to two intertwined technological aspects: the selection platform and the recombinant antibody repertoires. In accordance with these areas of interest, it is the goal of this chapter to describe the various selection tools and antibody libraries existing, with emphasis on the later, and their applications. This chapter gives a far from exhaustive, subjective "historic account" of the field, describing the selection platforms, the different formats of antibody repertoires and the applications of both for selecting recombinant antibodies. Several excellent books provide detailed protocols for constructing antibody libraries and selecting antibodies from those libraries [5-13]. Such books may guide a newcomer to the field in the fine details of antibody engineering. We would like to offer advice to the novice: although seemingly simple, effective library construction and antibody isolation provide best benefits in the hands of professionals. It is an art as much as it is science.

  13. Development of monoclonal antibodies and quantitative ELISAs targeting insulin-degrading enzyme

    Directory of Open Access Journals (Sweden)

    Dickson Dennis W


    Full Text Available Abstract Background Insulin-degrading enzyme (IDE is a widely studied zinc-metalloprotease implicated in the pathogenesis of type 2 diabetes mellitus, Alzheimer disease (AD and varicella zoster virus infection. Despite more than six decades of research on IDE, progress has been hampered by the lack of well-characterized reagents targeting this biomedically important protease. To address this important need, we generated and characterized new mouse monoclonal antibodies (mAbs targeting natively folded human and rodent IDE. Results Eight monoclonal hybridoma cell lines were derived in house from mice immunized with full-length, natively folded, recombinant human IDE. The mAbs derived from these lines were shown to detect IDE selectively and sensitively by a wide range of methods. Two mAbs in particular—designated 6A1 and 6H9—proved especially selective for IDE in immunocytochemical and immunohistochemical applications. Using a variety of methods, we show that 6A1 selectively detects both human and rodent IDE, while 6H9 selectively detects human, but not rodent, IDE, with both mAbs showing essentially no cross reactivity with other proteins in these applications. Using these novel anti-IDE mAbs, we also developed sensitive and quantitative sandwich ELISAs capable of quantifying IDE levels present in human brain extracts. Conclusion We succeeded in developing novel mAbs that selectively detect rodent and/or human IDE, which we have shown to be suitable for a wide range of applications, including western blotting, immunoprecipitation, immunocytochemistry, immunohistochemistry, and quantitative sandwich ELISAs. These novel anti-IDE mAbs and the assays derived from them constitute important new tools for addressing many unresolved questions about the basic biology of IDE and its role in multiple highly prevalent human diseases.

  14. Hapten synthesis and antibody production for the development of a melamine immunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Lei Hongtao; Shen Yudong; Song Lijun; Yang Jinyi [Key Laboratory of Food Safety of Guangdong Province/Institute of Food Quality and Safety, South China Agricultural University, Wushan Road, Tianhe District, Guangzhou 510642, Guangdong (China); Chevallier, Olivier P.; Haughey, Simon A. [Institute of Agri-Food and Land Use, Queen' s University Belfast, Belfast BT9 5AG, Northern Ireland (United Kingdom); Wang Hong [Key Laboratory of Food Safety of Guangdong Province/Institute of Food Quality and Safety, South China Agricultural University, Wushan Road, Tianhe District, Guangzhou 510642, Guangdong (China); Sun Yuanming, E-mail: [Key Laboratory of Food Safety of Guangdong Province/Institute of Food Quality and Safety, South China Agricultural University, Wushan Road, Tianhe District, Guangzhou 510642, Guangdong (China); Elliott, Christopher T., E-mail: [Institute of Agri-Food and Land Use, Queen' s University Belfast, Belfast BT9 5AG, Northern Ireland (United Kingdom)


    The incorporation of melamine into food products is banned but its misuse has been widely reported in both animal feeds and food. The development of a rapid screening immunoassay for monitoring of the substance is an urgent requirement. Two haptens of melamine were synthesized by introducing spacer arms of different lengths and structures on the triazine ring of the analyte molecular structure. 6-Aminocaproic acid and 3-mercaptopropionic acid were reacted with 2-chloro-4,6-diamino-1,3,5-triazine (CAAT) to produce hapten 1 [3-(4,6-diamino-1,6-dihydro-1,3,5-triazin-2-ylamino) hexanoic acid] and hapten 2 [3-(4,6-diamino-1,6-dihydro-1,3,5-triazin-2-ylthio) propanoic acid], respectively. The molecular structures of the two haptens were identified by {sup 1}H nuclear magnetic resonance spectrometry, mass spectrometry and infrared spectrometry. An immunogen was prepared by coupling hapten 1 to bovine serum albumin (BSA). Two plate coating antigens were prepared by coupling both haptens to egg ovalbumin (OVA). A competitive indirect enzyme-linked immunosorbent assay (ciELISA) was developed to evaluate homogeneous and heterogeneous assay formats. The results showed that polyclonal antibodies with high titers were obtained, and the heterogeneous immunoassay format demonstrated a better performance with an IC{sub 50} of 70.6 ng mL{sup -1}, a LOD of 2.6 ng mL{sup -1} and a LOQ of 7.6 ng mL{sup -1}. Except for cyromazine, no obvious cross-reactivity to common compounds was found. The data showed that the hapten synthesis was successful and the resultant antisera could be used in an immunoassay for the rapid and sensitive detection of this banned chemical.

  15. Accelerated formulation development of monoclonal antibodies (mAbs) and mAb-based modalities: review of methods and tools. (United States)

    Razinkov, Vladimir I; Treuheit, Michael J; Becker, Gerald W


    More therapeutic monoclonal antibodies and antibody-based modalities are in development today than ever before, and a faster and more accurate drug discovery process will ensure that the number of candidates coming to the biopharmaceutical pipeline will increase in the future. The process of drug product development and, specifically, formulation development is a critical bottleneck on the way from candidate selection to fully commercialized medicines. This article reviews the latest advances in methods of formulation screening, which allow not only the high-throughput selection of the most suitable formulation but also the prediction of stability properties under manufacturing and long-term storage conditions. We describe how the combination of automation technologies and high-throughput assays creates the opportunity to streamline the formulation development process starting from early preformulation screening through to commercial formulation development. The application of quality by design (QbD) concepts and modern statistical tools are also shown here to be very effective in accelerated formulation development of both typical antibodies and complex modalities derived from them.

  16. Development and Evaluation of a Fluorescent Antibody-Drug Conjugate for Molecular Imaging and Targeted Therapy of Pancreatic Cancer.

    Directory of Open Access Journals (Sweden)

    Steve Knutson

    Full Text Available Antibodies are widely available and cost-effective research tools in life science, and antibody conjugates are now extensively used for targeted therapy, immunohistochemical staining, or in vivo diagnostic imaging of cancer. Significant advances in site-specific antibody labeling technologies have enabled the production of highly characterized and homogenous conjugates for biomedical purposes, and some recent studies have utilized site-specific labeling to synthesize bifunctional antibody conjugates with both imaging and drug delivery properties. While these advances are important for the clinical safety and efficacy of such biologics, these techniques can also be difficult, expensive, and time-consuming. Furthermore, antibody-drug conjugates (ADCs used for tumor treatment generally remain distinct from conjugates used for diagnosis. Thus, there exists a need to develop simple dual-labeling methods for efficient therapeutic and diagnostic evaluation of antibody conjugates in pre-clinical model systems. Here, we present a rapid and simple method utilizing commercially available reagents for synthesizing a dual-labeled fluorescent ADC. Further, we demonstrate the fluorescent ADC's utility for simultaneous targeted therapy and molecular imaging of cancer both in vitro and in vivo. Employing non-site-specific, amine-reactive chemistry, our novel biopharmaceutical theranostic is a monoclonal antibody specific for a carcinoembryonic antigen (CEA biomarker conjugated to both paclitaxel and a near-infrared (NIR, polyethylene glycol modified (PEGylated fluorophore (DyLight™ 680-4xPEG. Using in vitro systems, we demonstrate that this fluorescent ADC selectively binds a CEA-positive pancreatic cancer cell line (BxPC-3 in immunofluorescent staining and flow cytometry, exhibits efficient internalization kinetics, and is cytotoxic. Model studies using a xenograft of BxPC-3 cells in athymic mice also show the fluorescent ADC's efficacy in detecting tumors in

  17. Comparison of serological tests for the detection of ovine and caprine antibody to Brucella melitensis. (United States)

    Nielsen, K; Gall, D; Smith, P; Balsevicius, S; Garrido, F; Ferrer, M Durán; Biancifiori, F; Dajer, A; Luna, E; Samartino, L; Bermudez, R; Moreno, F; Renteria, T; Corral, A


    The indirect enzyme-linked immunosorbent assay (IELISA), the competitive enzyme-linked immunosorbent assay (CELISA) and the fluorescence polarisation assay (FPA) were evaluated with sera from sheep experimentally infected with Brucella melitensis and negative Canadian sheep. The sensitivity and specificity of the assays were as follows: IELISA: 91.7% and 97.6%, CELISA: 75.0% and 99.8% and FPA: 91.7% and 89.5%. Sera from the same experimental population were divided according to serological reaction in the rose bengal agglutination test (RBT) and the complement fixation test (CFT). Reactivity relative to the RBT positive and CFT positive sera were as follows: IELISA: 99.7%, CELISA: 93.2% and FPA: 99.1%. Since sera from goats with proven B. melitensis infection were not available, 699 sera from goats judged positive in the buffered antigen plate agglutination test (BPAT) and CFT and 982 BPAT/CFT negative Canadian goats were used. The sensitivity and specificity of the assays relative to the BPAT and CFT positive sera were: IELISA: 99.4% and 98.0%, CELISA: 95.4% and 97.1% and FPA: 92.7% and 99.8%.

  18. 330 W Cryocooler Developments and Testing (United States)

    Emery, N.; Caughley, A.; Nation, M.; Kimber, A.; Allpress, N.; Reynolds, H.; Boyle, C.; Meier, J.; Tanchon, J.


    Fabrum Solutions in association with Callaghan Innovation and Absolut System has developed a 330 W pulse tube cryocooler based on Callaghan Innovation's novel diaphragm pressure wave generators (DPWG). A cost-effective, long life and robust cryocooler has been achieved due to the pulse tube's lack of moving parts and the DPWG's metal diaphragms separating the working gas from the oil lubricated drive mechanism. A 330 cc DPWG was designed and manufactured to run with an inline pulse tube. Absolut System carried out the pulse tube design; manufacture was by Fabrum Solutions, with integration and testing by Callaghan Innovation. The 330 W pulse tubes were run as cryocoolers mounted to 330 cc DPWG's. 480 W of cooling power at 77 K was achieved (target was 330 W at 77 K) from 7kW PV power and 12 kW of electrical input power. An endurance cryocooler was assembled with the left over parts from the optimization exercise. The endurance cryocooler was assembled to run as a liquefier. Calculation showed that 1 litre per hour of liquid nitrogen production was possible from 91 W of cooling power at 83 K. 1 litre per hour of liquid nitrogen was successfully produced for every 100 W of cooling power at 83 K, in a commercial application. Three more 330 W pulse tubes have been mounted to a single 1000 cc DPWG to produce > 1 kW of cooling power at 77 K. The commercialisation of the 1000 W cryocooler is the topic of another paper presented at this conference. Details of the design, development, testing and integration of the 330 W cryocooler are presented in this paper.



    Eu. V. Grishin; T. I. Valiakina


    The present study focuses on development of monoclonal antibodies (MAbs) which specifically interact with cholera toxin or heat labile enterotoxin of E. coli. Such monoclonal antibodies MAbs are possessed of ability to identify cholera toxin or heat labile enterotoxin in different immunochemical assays. We obtained hybridoma clones which produced monoclonal antibodies of IgG isotypes to cholera toxin and heat labile enterotoxin. On application of the method of serial dilutions we selected the...

  20. Red Blood Cell Antibody Identification (United States)

    ... ID, RBC; RBC Ab ID Formal name: Red Blood Cell Antibody Identification Related tests: Direct Antiglobulin Test ; RBC ... I should know? How is it used? Red blood cell (RBC) antibody identification is used as a follow- ...

  1. Antissaliva Antibodies of Lutzomyia Longipalpis in area of Visceral Leishmaniasis. (United States)

    Fraga, Thiago Leite; Fernandes, Magda Freitas; Pontes, Elenir Rose Jardim Cury; Levay, Ana Paula Silva; Almeida da Cunha, Elenice Brandão; França, Adriana de Oliveira; Dorval, Maria Elizabeth Cavalheiros


    The aim of the present study was to assess the presence of antissaliva antibodies of Lutzomyia longipalpis in human hosts living in area of visceral leishmaniasis, located in the Center-West region of Brazil. The presence of antissaliva antibodies of L. longipalpis exhibited a strong correlation with the protection and development of antibodies against Leishmania sp. Of the 492 children studied, elevated antissaliva antibodies of L. longipalpis were detected in 38.4% of the participants. There was a higher percentage of positivity (64.7%) among children who exhibited anti-Leishmania sp. antibodies and among those who were positive in the delayed hypersensitivity test (34.8%).

  2. The antibody mining toolbox


    D'Angelo, Sara; Glanville, Jacob; Ferrara, Fortunato; Naranjo, Leslie; Gleasner, Cheryl D.; Shen, Xiaohong; Bradbury, Andrew RM; Kiss, Csaba


    In vitro selection has been an essential tool in the development of recombinant antibodies against various antigen targets. Deep sequencing has recently been gaining ground as an alternative and valuable method to analyze such antibody selections. The analysis provides a novel and extremely detailed view of selected antibody populations, and allows the identification of specific antibodies using only sequencing data, potentially eliminating the need for expensive and laborious low-throughput ...

  3. Development of rabbit monoclonal antibodies for detection of alpha-dystroglycan in normal and dystrophic tissue.

    Directory of Open Access Journals (Sweden)

    Marisa J Fortunato

    Full Text Available Alpha-dystroglycan requires a rare O-mannose glycan modification to form its binding epitope for extracellular matrix proteins such as laminin. This functional glycan is disrupted in a cohort of muscular dystrophies, the secondary dystroglycanopathies, and is abnormal in some metastatic cancers. The most commonly used reagent for detection of alpha-dystroglycan is mouse monoclonal antibody IIH6, but it requires the functional O-mannose structure for recognition. Therefore, the ability to detect alpha-dystroglycan protein in disease states where it lacks the full O-mannose glycan has been limited. To overcome this hurdle, rabbit monoclonal antibodies against the alpha-dystroglycan C-terminus were generated. The new antibodies, named 5-2, 29-5, and 45-3, detect alpha-dystroglycan from mouse, rat and pig skeletal muscle by Western blot and immunofluorescence. In a mouse model of fukutin-deficient dystroglycanopathy, all antibodies detected low molecular weight alpha-dystroglycan in disease samples demonstrating a loss of functional glycosylation. Alternately, in a porcine model of Becker muscular dystrophy, relative abundance of alpha-dystroglycan was decreased, consistent with a reduction in expression of the dystrophin-glycoprotein complex in affected muscle. Therefore, these new rabbit monoclonal antibodies are suitable reagents for alpha-dystroglycan core protein detection and will enhance dystroglycan-related studies.

  4. Rapid Identification of Dengue Virus Serotypes Using Monoclonal Antibodies in an Indirect Immunofluorescence Test. (United States)


    encephalitis(TBH-28), West Nile(E-101), Yellow fever(French neurotropic and 17D strains), and Zika. Two Sandfly Fever viruses (213452 and Candiru) were...thaw at room temperature for 5 minutes,. washed with PBS and drained. The cells were first incubated at 35°C wit an appropriate dilution of hybridoma...include IB8, IB10, ICl0, 4G2, 2C4, 1B6, 4BI0, and ID7 which generally reacted with all of the flaviviruses tested and did not recognize the sandfly

  5. Development of lubricant test for punching and blanking

    DEFF Research Database (Denmark)

    Olsson, David Dam


    The background for development of new lubricants Requirements to lubricant test for punching Methods of evaluating lubricants Test equipment developed at DTU Conclusion.......The background for development of new lubricants Requirements to lubricant test for punching Methods of evaluating lubricants Test equipment developed at DTU Conclusion....

  6. Avian Diagnostic and Therapeutic Antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, David Sherman [UND SMHS


    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.

  7. Antineutrophil Cytoplasmic Antibodies Testing in a Large Cohort of Unselected Greek Patients

    Directory of Open Access Journals (Sweden)

    Konstantinos Tsiveriotis


    Full Text Available Objective. To retrospectively evaluate ANCA testing in a cohort of unselected Greek in- and outpatients. Methods. In 10803 consecutive serum samples, ANCA were tested by indirect immunofluorescence (IIF and ELISA. ELISA in inpatients was performed only on IIF positive sera. Results. Low prevalence (6.0% of IIF positive samples was observed. Among these samples, 63.5% presented perinuclear (p-ANCA, 9.3% cytoplasmic (c-ANCA and 27.2% atypical (x-ANCA pattern. 16.1% of p-ANCA were antimyeloperoxidase (anti-MPO positive, whereas 68.3% of c-ANCA were antiproteinase-3 (anti-PR3 positive. Only 17 IIF negative outpatients' samples were ELISA positive. ANCA-associated vasculitides (AAV, connective tissue disorders and gastrointestinal disorders represented 20.5%, 23.9%, and 21.2% of positive results, respectively. AAV patients exhibited higher rates of MPO/PR3 specificity compared to non-AAV (93.8% versus 8%. Conclusions. This first paper on Greek patients supports that screening for ANCA by IIF and confirming positive results by ELISA minimize laboratory charges without sacrificing diagnostic accuracy.

  8. Antineutrophil cytoplasmic antibodies testing in a large cohort of unselected greek patients. (United States)

    Tsiveriotis, Konstantinos; Tsirogianni, Alexandra; Pipi, Elena; Soufleros, Konstantinos; Papasteriades, Chryssa


    Objective. To retrospectively evaluate ANCA testing in a cohort of unselected Greek in- and outpatients. Methods. In 10803 consecutive serum samples, ANCA were tested by indirect immunofluorescence (IIF) and ELISA. ELISA in inpatients was performed only on IIF positive sera. Results. Low prevalence (6.0%) of IIF positive samples was observed. Among these samples, 63.5% presented perinuclear (p-ANCA), 9.3% cytoplasmic (c-ANCA) and 27.2% atypical (x-ANCA) pattern. 16.1% of p-ANCA were antimyeloperoxidase (anti-MPO) positive, whereas 68.3% of c-ANCA were antiproteinase-3 (anti-PR3) positive. Only 17 IIF negative outpatients' samples were ELISA positive. ANCA-associated vasculitides (AAV), connective tissue disorders and gastrointestinal disorders represented 20.5%, 23.9%, and 21.2% of positive results, respectively. AAV patients exhibited higher rates of MPO/PR3 specificity compared to non-AAV (93.8% versus 8%). Conclusions. This first paper on Greek patients supports that screening for ANCA by IIF and confirming positive results by ELISA minimize laboratory charges without sacrificing diagnostic accuracy.

  9. High-Throughput Testing of Antibody-Dependent Binding Inhibition of Placental Malaria Parasites

    DEFF Research Database (Denmark)

    Nielsen, Morten A; Salanti, Ali


    The particular virulence of Plasmodium falciparum manifests in diverse severe malaria syndromes as cerebral malaria, severe anemia and placental malaria. The cause of both the severity and the diversity of infection outcome, is the ability of the infected erythrocyte (IE) to bind a range......-throughput assay used in the preclinical and clinical development of a VAR2CSA based vaccine against placental malaria....

  10. Development of Monoclonal Antibodies That Target 1-Cys Peroxiredoxin and Differentiate Plasmodium falciparum from P. vivax and P. knowlesi. (United States)

    Hakimi, Hassan; Nguyen, Thu-Thuy; Suganuma, Keisuke; Masuda-Suganuma, Hirono; Angeles, Jose Ma M; Inoue, Noboru; Kawazu, Shin-Ichiro


    Prompt and accurate diagnosis of malarial patients is a crucial factor in controlling the morbidity and mortality of the disease. Effective treatment decisions require a correct diagnosis among mixed-species malarial patients. Differential diagnosis is particularly important in cases of Plasmodium vivax, a species that shares endemicity with P. falciparum in most endemic areas. Moreover, it is difficult to identify P. knowlesi on the basis of morphology alone, and rapid diagnostic tests are still not available for this malaria species. Therefore, the development of diagnostic tests applicable to the field is urgently needed. 1-Cys peroxiredoxin (1-Cys-Prx) in P. falciparum is abundantly expressed in the mature asexual stages, making it a promising candidate as a diagnostic antigen. In this study, we produced five monoclonal antibodies (mAbs) against P. falciparum 1-Cys-Prx (Pf1-Cys-Prx) by immunizing BALB/c mice with recombinant Pf1-Cys-Prx and subsequent hybridoma production. Cross reactivity of established mAbs with the orthologous molecule of Pf1-Cys-Prx in P. vivax (Pv1-Cys-Prx) and P. knowlesi (Pk1-Cys-Prx) was examined. Western blot analyses showed that three mAbs reacted with Pv1-Cys-Prx and Pk1-Cys-Prx but two mAbs did not. These results indicate that the two mAbs were effective in differentiating P. falciparum from P. vivax and P. knowlesi and could be used in differential diagnosis as well as comparative molecular studies of human Plasmodium species.

  11. Strip reduction testing of lubricants developed during ENFORM project

    DEFF Research Database (Denmark)

    Gazvoda, S.; Andreasen, Jan Lasson; Olsson, David Dam

    Strip reduction testing of lubricants developed during ENFORM project. Experiments were conducted with the strip reduction test [1] in order to classify experimental lubricants, developed during concerned project. One reference lubricant was used during testing.......Strip reduction testing of lubricants developed during ENFORM project. Experiments were conducted with the strip reduction test [1] in order to classify experimental lubricants, developed during concerned project. One reference lubricant was used during testing....

  12. Development of an Immunoassay for Chloramphenicol Based on the Preparation of a Specific Single-Chain Variable Fragment Antibody. (United States)

    Du, Xin-jun; Zhou, Xiao-nan; Li, Ping; Sheng, Wei; Ducancel, Frédéric; Wang, Shuo


    Specific antibodies are essential for the immune detection of small molecule contaminants. In the present study, the heavy and light variable regions (V(H )and V(L)) of the immunoglobulin genes from a hybridoma secreting a chloramphenicol (CAP)-specific monoclonal antibody (mAb) were cloned and sequenced. In addition, the light and heavy chains obtained from the monoclonal antibody were separated using SDS-PAGE and analyzed using Orbitrap mass spectrometry. The results of DNA sequencing and mass spectrometry analysis were compared, and the V(H) and V(L) chains specific for CAP were determined and used to construct a single-chain variable fragment (scFv). This fragment was recombinantly expressed as a soluble scFv-alkaline phosphatase fusion protein and used to develop a direct competitive ELISA. Compared with the parent mAb, scFv exhibits lower sensitivity but better food matrix resistance. This work highlights the application of engineered antibodies for CAP detection.

  13. Detection of antibody responses by using haemagglutination inhibiton test and the protection titer of avian influenza virus H5N1 subtype

    Directory of Open Access Journals (Sweden)

    Risa Indriani


    Full Text Available Study on the detection of antibody responses using haemagglutination inhibition (HI test and the protection titer to Avian influenza (AI virus H5N1 subtype local isolate has been conducted at the Research Institute for Veterinary Science (RIVS. A total number of 50 village chicken (10 chicken served as un-injected controls and 30 quail were injected intramuscularly with inactivated virus of AI H5N1 subtype local isolate. Serum samples were collected 3 weeks after injection and were tested using haemagglutination inhibition tests. The correlation between antibody titer and its protection to AI virus H5N1 local isolate were measured by challenging the birds with AI virus H5N1 local isolate The HI test was then used to determine field serum samples. A total number of 48 village chicken from three (3 Districts (Bekasi, Tangerang and Bogor and 96 quails from two (2 farms in District of Sukabumi which were all vaccinated with commercial AI adjuvant vaccine were sampled. The study revealed that village chicken and quails showed antibody responses after 3 weeks vaccination and that titer of ≥ 3 log 2 was able to protect chicken and quails when they were challenged with local isolate virus. Based on this result, village chicken field samples from Districts of Tangerang, Bekasi and Bogor showed antibody titer which will protect 50, 100 and 85% of the flocks respectively. While quail field samples from Farm I and Farm II in District of Sukabumi showed antibody titer which will protect 60-100% and 0-80% of the flocks respectively. It is concluded that the study has successfully measured antibody titer to AI virus H5N1 subtype which protect village chicken and quails from local isolate virus challenge so that the results will be used to analyze field serum samples after vaccination program to eradicate AI from Indonesia.

  14. Indirect Haemagglutination Test in Comparison with ELISA for Detection of Antibodies against Invasive Amoebiasis (United States)

    Dhanalakshmi, Sankaramoorthy; Meenachi, Chidambaram


    Introduction Diagnosis of amoebiasis is based on combination of tests like microscopy, imaging, serology and molecular methods. In absence of molecular techniques, serology can be used as an alternative aid. Various serological techniques were reported with different sensitivity and specificity. The diagnostic efficiency of these assays mainly depends on the characteristics of antigen that is being used and various conditions of performance. Aim To evaluate the efficiency of recombinant calcium binding domain containing protein by Indirect Haemagglutination Assay (IHA) against a commercial ELISA among amoebic liver abscess cases and control group. Materials and Methods The study was carried out during the period of 2011-2015 and blood samples were collected from suspected amoebiasis cases who were attending the clinics of Medicine and Paediatrics department, JIPMER. A total of 200 sera samples which included 100 Amoebic Liver Abscess (ALA), 50 cases of other parasitic infections and liver diseases and 50 presumed healthy controls were examined by IHA and commercial ELISA. In brief, chick cells were stabilized by Double Aldehyde Sensitization (DAS) method. Optimum Sensitizing Dose (OSD) of the antigen was determined. The test was performed in a U-bottomed microtiter plate with recombinant amoebic antigen (12.5μg/ml), incubated at Room Temperature (RT) for 2 hours. RIDASCREEN Entamoeba IgG ELISA kit which is commercially available was used to evaluate the samples as per manufacturer’s instruction. Results The overall sensitivity and specificity of the IHA was 62% and 96%, respectively when compared to ELISA having sensitivity and specificity of 69% and 90%, respectively. The positive predictive value of the IHA was 91% while negative predictive value was 79%. Similarly, the positive predictive value of the ELISA was 87% while negative predictive value was 74%. Conclusion As serology heavily suffers due to lack of a standardised test system employing the native

  15. Develope Monoclonal Antibody against Foot-and-mouth Disease Virus A Type

    Institute of Scientific and Technical Information of China (English)

    Tong Lin; Jing Li; Jun-jun Shao; Guo-zheng Cong; Jun-zheng Du; Shan-dian Gao; Hui-yun Chang


    In order to develop an anti-FMDV A Type monoclonal antibo by (mAb),BABL/c mice were immunized with FMDV A type.Monoclonal antibodies (mAbs) 7B11 and 8H4 against Foot-and-mouth disease virus (FMDV) serotype A were produced by fusing SP2/O myeloma cells with splenocyte from the mouse immunized with A/AV88.The microneutralization titer of the mAbs 7B11 and 8H4 were 1024 and 512,respectively.Both mAbs contain kappa light chains,the mAbs were IgG1.In order to define the mAbs binding epitopes,the reactivity of these mAbs against A Type FMDV,were examined using indirect ELISA,the result showed that both mAbs reacted with A Type FMDV.These mAbs may be used for further vaccine studies,diagnostic methods,prophylaxis,etiological and immunological research on FMDV.Characterization of these ncindicated that prepared anti-FMDV A mAbs had no cross-reactivity with Swine Vesicular Disease (SVD) or FMDV O,Asial and C Type antigens.Their titers in abdomen liquor were 1:5×106 and 1:2×106,respectively.7B11 was found to be of subtype IgG1,8H4 was classified as IgG2b subtype.The mAbs prepared in this study,are specific for detection of FMDV serotype A,and is potentially useful for pen-side diagnosis.

  16. Enhanced potency of a fucose-free monoclonal antibody being developed as an Ebola virus immunoprotectant. (United States)

    Zeitlin, Larry; Pettitt, James; Scully, Corinne; Bohorova, Natasha; Kim, Do; Pauly, Michael; Hiatt, Andrew; Ngo, Long; Steinkellner, Herta; Whaley, Kevin J; Olinger, Gene G


    No countermeasures currently exist for the prevention or treatment of the severe sequelae of Filovirus (such as Ebola virus; EBOV) infection. To overcome this limitation in our biodefense preparedness, we have designed monoclonal antibodies (mAbs) which could be used in humans as immunoprotectants for EBOV, starting with a murine mAb (13F6) that recognizes the heavily glycosylated mucin-like domain of the virion-attached glycoprotein (GP). Point mutations were introduced into the variable region of the murine mAb to remove predicted human T-cell epitopes, and the variable regions joined to human constant regions to generate a mAb (h-13F6) appropriate for development for human use. We have evaluated the efficacy of three variants of h-13F6 carrying different glycosylation patterns in a lethal mouse EBOV challenge model. The pattern of glycosylation of the various mAbs was found to correlate to level of protection, with aglycosylated h-13F6 providing the least potent efficacy (ED(50) = 33 μg). A version with typical heterogenous mammalian glycoforms (ED(50) = 11 μg) had similar potency to the original murine mAb. However, h-13F6 carrying complex N-glycosylation lacking core fucose exhibited superior potency (ED(50) = 3 μg). Binding studies using Fcγ receptors revealed enhanced binding of nonfucosylated h-13F6 to mouse and human FcγRIII. Together the results indicate the presence of Fc N-glycans enhances the protective efficacy of h-13F6, and that mAbs manufactured with uniform glycosylation and a higher potency glycoform offer promise as biodefense therapeutics.

  17. Development of a mouse-feline chimeric antibody against feline tumor necrosis factor-alpha (United States)

    DOKI, Tomoyoshi; TAKANO, Tomomi; HOHDATSU, Tsutomu


    Feline infectious peritonitis (FIP) is a fatal inflammatory disease caused by FIP virus infection. Feline tumor necrosis factor (fTNF)-alpha is closely involved in the aggravation of FIP pathology. We previously described the preparation of neutralizing mouse anti-fTNF-alpha monoclonal antibody (mAb 2–4) and clarified its role in the clinical condition of cats with FIP using in vitro systems. However, administration of mouse mAb 2–4 to cat may lead to a production of feline anti-mouse antibodies. In the present study, we prepared a mouse-feline chimeric mAb (chimeric mAb 2–4) by fusing the variable region of mouse mAb 2–4 to the constant region of feline antibody. The chimeric mAb 2–4 was confirmed to have fTNF-alpha neutralization activity. Purified mouse mAb 2–4 and chimeric mAb 2–4 were repeatedly administered to cats, and the changes in the ability to induce feline anti-mouse antibody response were investigated. In the serum of cats treated with mouse mAb 2–4, feline anti-mouse antibody production was induced, and the fTNF-alpha neutralization effect of mouse mAb 2–4 was reduced. In contrast, in cats treated with chimeric mAb 2–4, the feline anti-mouse antibody response was decreased compared to that of mouse mAb 2–4-treated cats. PMID:27264736

  18. Progress in the development of therapeutic antibodies targeting prion proteins and β-amyloid peptides

    Institute of Scientific and Technical Information of China (English)


    Prion diseases and Alzheimer’s disease (AD) are characterized by protein misfolding, and can lead to dementia. However, prion diseases are infectious and transmissible, while AD is not. The similarities and differences between these diseases have led researchers to perform comparative studies. In the last 2 decades, progress has been made in immunotherapy using anti-prion protein and anti-β-amyloid antibodies. In this study, we review new ideas and strategies for therapeutic antibodies targeting prion diseases and AD through conformation dependence.

  19. Obtaining of a rapid diagnostic test for Cholera, based on latex particles coupled with a monoclonal antibody against Vibrio cholera O1 lipopolysaccharide

    Directory of Open Access Journals (Sweden)

    Fátima Reyes-López


    Full Text Available Cholera is an acute contagious intestinal disease caused by ingestion of food or water contaminated with O1 and O139 serotypes of the bacterium Vibrio cholerae. Cholera is characterized by abundant secretory diarrhea leading to dehydration. Death occurs within hours without treatment, so early diagnosis is very important, especially at the beginning of the disease, because it is difficult to differentiate from other acute diarrheal diseases. The diagnostic golden test is the stool culture; however, it does not guarantee a rapid detection of the disease. Rapid tests have been recently developed; they are based on test strips and agglutination with latex particles, which are very effective, but difficult to acquire for their high prices. The objective of this research was to obtain a quick assay based on latex particles coupled with a monoclonal antibody (mAb against V. cholerae O1 lipopolysaccharide obtained in Finlay Institute. Latex particles of 0.8 µm were used in a 10% suspension, and they were coupled to the mAb (0.25 mg/ml for 2 hours at 37°C. The sensitivity, specificity and performance were evaluated in 84 stool samples from patients with presumptive diagnosis of cholera. The diagnostic test obtained showed no cross-reactivity against no-O1 strains and other enteropathogens. Latex diagnostic test showed values of sensitivity, specificity and efficacy of 97.87; 97.29 and 97.6% respectively, very similar to the commercial diagnostic test CTK- Biotech. The latex reagent obtained can be used in the rapid diagnosis of the disease.

  20. Recommendations on risk-based strategies for detection and characterization of antibodies against biotechnology products. (United States)

    Koren, Eugen; Smith, Holly W; Shores, Elizabeth; Shankar, Gopi; Finco-Kent, Deborah; Rup, Bonita; Barrett, Yu-Chen; Devanarayan, Viswanath; Gorovits, Boris; Gupta, Shalini; Parish, Thomas; Quarmby, Valerie; Moxness, Michael; Swanson, Steven J; Taniguchi, Gary; Zuckerman, Linda A; Stebbins, Christopher C; Mire-Sluis, Anthony


    The appropriate evaluation of the immunogenicity of biopharmaceuticals is of major importance for their successful development and licensure. Antibodies elicited by these products in many cases cause no detectable clinical effects in humans. However, antibodies to some therapeutic proteins have been shown to cause a variety of clinical consequences ranging from relatively mild to serious adverse events. In addition, antibodies can affect drug efficacy. In non-clinical studies, anti-drug antibodies (ADA) can complicate interpretation of the toxicity, pharmacokinetic (PK) and pharmacodynamic (PD) data. Therefore, it is important to develop testing strategies that provide valid assessments of antibody responses in both non-clinical and clinical studies. This document provides recommendations for antibody testing strategies stemming from the experience of contributing authors. The recommendations are intended to foster a more unified approach to antibody testing across the biopharmaceutical industry. The strategies proposed are also expected to contribute to better understanding of antibody responses and to further advance immunogenicity evaluation.

  1. Detection of filaria-specific IgG4 antibodies using Brugia Rapid test in individuals from an area highly endemic for Brugia timori. (United States)

    Supali, T; Rahmah, N; Djuardi, Y; Sartono, E; Rückert, Paul; Fischer, P


    The filarial parasite Brugia timori is of great public health importance in some islands of Eastern Indonesia. To establish a simple serological test for the identification and post-treatment monitoring of areas endemic for B. timori, a rapid immunochromatographic dipstick test (Brugia Rapid, BR) was evaluated on microfilaraemic and amicrofilaraemic individuals. This test is based on the detection of anti-filarial IgG4 antibodies that react with a recombinant Brugia malayi antigen (BmR1). In our study area on Alor island the prevalence of microfilaraemia was 26%. With the BR test, 100% of 196 sera from microfilaraemic persons and 76% of 563 sera from amicrofilaraemic persons, either symptomatic or asymptomatic, reacted positive. All 50 control sera from areas non-endemic for lymphatic filariasis gave negative BR test results. This study showed that the BR test can be also used to detect antibodies against B. timori. Due to the high prevalence of IgG4 antibodies as detected by the BR test (81%), no significant correlation with the prevalence of microfilaraemia could be detected within the endemic village. The BR test also shows great promise to be employed as a monitoring tool for B. timori in the framework of the Global Program to Eliminate Lymphatic Filariasis (GPELF).

  2. Distinct expression profiles of Notch-1 protein in human solid tumors: Implications for development of targeted therapeutic monoclonal antibodies


    Yuan Li; Burns, Janine A.; Carol A Cheney; et al


    Yuan Li1, Janine A Burns1, Carol A Cheney1, Ningyan Zhang1, Salvatore Vitelli1, Fubao Wang1, Andrew Bett2, Michael Chastain2, Laurent P Audoly1, Zhi-Qiang Zhang1,31Department of Biologics Research, 2Department of Vaccine Research, Merck Research Laboratories, West Point, PA, USA; 3Clinical Development Laboratory, Merck Research Laboratories, Rahway, NJ, USAAbstract: Biological therapies, such as monoclonal antibodies (mAbs) that target tumor-associated antigens have been considered an effecti...

  3. Antibodies Against Human BLyS and APRIL Attenuate EAE Development in Marmoset Monkeys

    NARCIS (Netherlands)

    S.A. Jagessar (Anwar); N. Heijmans (Nicole); J. Bauer; E. Blezer (Erwin); J.D. Laman (Jon); T.S. Migone (Thi-Sau); M.N. Devalaraja (Matt); B.A. 't Hart (Bert)


    textabstractB lymphocyte stimulator (BLyS, also indicated as BAFF (B-cell activating factor) and CD257), and A Proliferation Inducing Ligand (APRIL, CD256) are two members of the TNF superfamily with a central role in B cell survival. Antibodies against these factors have potential therapeutic relev

  4. Antibodies Against Human BLyS and APRIL Attenuate EAE Development in Marmoset Monkeys

    NARCIS (Netherlands)

    Jagessar, S. Anwar; Heijmans, Nicole; Bauer, Jan; Blezer, Erwin L. A.; Laman, Jon D.; Migone, Thi-Sau; Devalaraja, Matt N.; 't Hart, Bert A.


    B lymphocyte stimulator (BLyS, also indicated as BAFF (B-cell activating factor) and CD257), and A Proliferation Inducing Ligand (APRIL, CD256) are two members of the TNF superfamily with a central role in B cell survival. Antibodies against these factors have potential therapeutic relevance in auto

  5. Role of antibodies in developing drugs that target G-protein-coupled receptor dimers. (United States)

    Hipser, Chris; Bushlin, Ittai; Gupta, Achla; Gomes, Ivone; Devi, Lakshmi A


    G-protein-coupled receptors are important molecular targets in drug discovery. These receptors play a pivotal role in physiological signaling pathways and are targeted by nearly 50% of currently available drugs. Mounting evidence suggests that G-protein-coupled receptors form dimers, and various studies have shown that dimerization is necessary for receptor maturation, signaling, and trafficking. However, the physiological implications of dimerization in vivo have not been well explored because detection of GPCR dimers in endogenous systems has been a challenging task. One exciting new approach to this challenge is the generation of antibodies against specific G-protein-coupled receptor dimers. Such antibodies could be used as tools for characterization of heteromer-specific function; as reagents for their purification, tissue localization, and regulation in vivo; and as probes for mapping their functional domains. In addition, such antibodies could serve as alternative ligands for G-protein-coupled receptor heteromers. Thus, heteromer-specific antibodies represent novel tools for the exploration and manipulation of G-protein-coupled receptor-dimer pharmacology.

  6. Development and characterization of mouse monoclonal antibodies against monomeric dengue virus non-structural glycoprotein 1 (NS1). (United States)

    Gelanew, Tesfaye; Poole-Smith, B Katherine; Hunsperger, Elizabeth


    Dengue virus (DENV) nonstructural-1 (NS1) glycoprotein is useful for diagnosis of DENV infections in the first 8 days of illness with any of the four serotypes (DENV-1, DENV-2, DENV-3 and DENV-4). However, NS1 diagnostics are less sensitive for secondary DENV infections so the utility of NS1 diagnostics in dengue endemic countries where there is predominantly secondary infections is being questioned. Heat-mediated immunecomplex dissociation (ICD) prior to testing serum samples can significantly improve NS1 test sensitivity in secondary infections but requires monoclonal antibodies (MAbs) reactive to heat-denatured NS1. In order to incorporate a simple heat-mediated ICD step, a crucial step was to develop new MAbs with high affinity and specificity to heat-denatured DENV NS1 protein. In the present study, six new MAbs were isolated from BALB/c mice immunized with recombinant monomeric NS1 of DENV-1 and DENV-2. Characterization using three different methods: indirect ELISA, fixed cell ELISA and western blot revealed that all six MAbs are serotype-cross-reactive and capable of recognizing dimeric and hexameric isoforms as well as heat-denatured NS1 from all four DENV serotypes. No cross-reactivity to NS1 of West Nile virus and Yellow fever virus was observed on western blot and indirect ELISA. Five of the six MAbs mapped to the DENV NS1 region of 105-119 amino acids. The remaining MAb mapped to DENV NS1 region of 25-39 amino acids. These two NS1 regions were found to be highly conserved among all four DENV serotypes by sequences analysis and database comparison. These MAbs were used to develop an NS1 capture ELISA and tested using a small panel of clinical specimens. The results from the NS1 capture ELISA indicated at least a three-fold increase in NS1 antigen detection in heat-denatured samples compared to untreated specimens. Furthermore, artificial immunecomplexed results also demonstrated the binding efficiency of these MAbs to heat denatured NS1. Taken together

  7. Development of a mouse monoclonal antibody cocktail for post-exposure rabies prophylaxis in humans.

    Directory of Open Access Journals (Sweden)

    Thomas Müller

    Full Text Available As the demand for rabies post-exposure prophylaxis (PEP treatments has increased exponentially in recent years, the limited supply of human and equine rabies immunoglobulin (HRIG and ERIG has failed to provide the required passive immune component in PEP in countries where canine rabies is endemic. Replacement of HRIG and ERIG with a potentially cheaper and efficacious alternative biological for treatment of rabies in humans, therefore, remains a high priority. In this study, we set out to assess a mouse monoclonal antibody (MoMAb cocktail with the ultimate goal to develop a product at the lowest possible cost that can be used in developing countries as a replacement for RIG in PEP. Five MoMAbs, E559.9.14, 1112-1, 62-71-3, M727-5-1, and M777-16-3, were selected from available panels based on stringent criteria, such as biological activity, neutralizing potency, binding specificity, spectrum of neutralization of lyssaviruses, and history of each hybridoma. Four of these MoMAbs recognize epitopes in antigenic site II and one recognizes an epitope in antigenic site III on the rabies virus (RABV glycoprotein, as determined by nucleotide sequence analysis of the glycoprotein gene of unique MoMAb neutralization-escape mutants. The MoMAbs were produced under Good Laboratory Practice (GLP conditions. Unique combinations (cocktails were prepared, using different concentrations of the MoMAbs that were capable of targeting non-overlapping epitopes of antigenic sites II and III. Blind in vitro efficacy studies showed the MoMab cocktails neutralized a broad spectrum of lyssaviruses except for lyssaviruses belonging to phylogroups II and III. In vivo, MoMAb cocktails resulted in protection as a component of PEP that was comparable to HRIG. In conclusion, all three novel combinations of MoMAbs were shown to have equal efficacy to HRIG and therefore could be considered a potentially less expensive alternative biological agent for use in PEP and prevention of

  8. Antimitochondrial antibody (United States)

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

  9. Seroepidemiological detection of antibodies against Leptospira spp using microscopic agglutination test in Urmia cows and sheep

    Directory of Open Access Journals (Sweden)

    Ramin Ag


    Full Text Available The study was designed to determine the level of incidence, titer and various serovars of leptospira in 203 cows and 166 sheep at Urmia abattoir in 2011. Blood samples were collected during the slaughter of animals and sera were separated to evaluate the serological reaction to Leptospira spp by Microscopic Agglutination Test (MAT using live antigens representing Leptospira interrogans serogroups: pomona, grippotyphosa, canicola, hardjo, icterrohaemoragiae, and ballum. Overall, 36% of cows and 19.3% of sheep including 33.8% of bulls, 40.5% of female cows, 18.3% of rams and 25% of ewes had a positive reaction to at least one of the leptospira serovars. The most prevalent serovars in cows were pomona (22.7%, grippotyphosa (13.8%, and hardjo (8.4%, and in sheep were grippotyphosa (66.7%, pomona (26.2% and canicola (7.1%. Other serovars were not detected in cows and sheep. The most prevalent serological titers of 1:100 and 1:200 in cows was 18.2% and 26.6%, and for sheep were 13.5% and 8%, respectively, and of 1:400 in sheep was 2.3%. Cows with a positive reaction to one, two and three serovars were 28.6%, 5.9%, and 1.5% and sheep positive to one and two serovars were 13.3% and 6%, respectively. Age comparison in seropositive cows and sheep showed a significantly increased infection (p<0.05 from young to adult ruminants, while no differences were seen regarding gender. The main mixed serovars were between grippotyphosa/pomona, grippotyphosa/canicola and canicola/pomona. The gender comparison of the serovars' distribution revealed that the pomona and grippotyphosa were predominant among other leptospiral serovars in cows and sheep, respectively. In conclusion, the rate of leptospirosis in Urmia cows was about 2 fold in sheep. The most current serovars in cows and sheep were pomona and grippotyphosa, respectively. The majority of animals was infected with one serovar, but polyserovars, are also possible. The highest titer (1:200 was observed in cows

  10. An Investigation into the Development of a Spoken English Test

    Institute of Scientific and Technical Information of China (English)



    This paper investigates the development of a spoken English test. The nature of speaking test and its design principles are first reviewed. Then the procedure of the test development is elaborated in detail,namely,design stage,construction stage and try out stage. The challenges facing the development of spoken test are finally discussed.

  11. Serologic test systems development. Progress report, October 1, 1978-September 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Seawright, G.L.; Sanders, W.M.; Hollstein, U.; Butler, J.E.; Mills, K.W.; Despommier, D.D.; Zimmerman, W.J.; Martinez, E.; Hindman, K.R.; Payne, R.J.


    Work has continued on the development and automation of enzyme immunoassays (EIA) for detecting diseases and toxic agents in food animals. Further evaluations were made of the Technicon Autoanalyzer II(AAII) for conducting totally automated EIAs. The problems investigated were machine carryover and assay variation. Modifications greatly reduced or eliminated carryover and produced acceptable levels of test variation. The EIA for swine trichinosis was significantly improved by the use of a new, partially purified antigen preparation. The result was improved detection of early seroconversions and reduced probability for false negatives and false positives. The amplified EIA was adapted as a diagnostic test for bovine brucellosis and studies were initiated for differentiating vaccinated and infected animals. Preliminary data indicate that the IgG/sub 1/ response may be diagnostic but further studies are necessary. Development of the EIA for detecting low molecular weight contaminants and residues in food products was also initiated. Compounds studied were the antibiotics chloramphenicol, tetracycline, and gentamicin; the mycotoxin, aflatoxin, and the shale oil toxin, 2-aminofluorene. Results indicate that chloramphenicol nonspecifically binds to antibody and interferes with antibody activity. Thus, the test is not yet satisfactory. Initial attempts to automate the gentamicin test were unsuccessful because of machine carryover but modifications of the AAII have produced encouraging preliminary data. Work is continuing on the development of EIAs for all of the compounds mentioned above. (ERB)

  12. Engineer Research and Development Center's Materials Testing Center (MTC) (United States)

    Federal Laboratory Consortium — The Engineer Research and Development Center's Materials Testing Center (MTC) is committed to quality testing and inspection services that are delivered on time and...

  13. Maternal autism-associated IgG antibodies delay development and produce anxiety in a mouse gestational transfer model. (United States)

    Braunschweig, Daniel; Golub, Mari S; Koenig, Claire M; Qi, Lihong; Pessah, Isaac N; Van de Water, Judy; Berman, Robert F


    A murine passive transfer model system was employed to ascertain the effects of gestational exposure to a single, intravenous dose of purified, brain-reactive IgG antibodies from individual mothers of children with autism (MAU) or mothers with typically developing children (MTD). Growth and behavioral outcomes in offspring were measured from postnatal days 8 to 65 in each group. Comparisons revealed alterations in early growth trajectories, significantly impaired motor and sensory development, and increased anxiety. This report demonstrates for the first time the effects of a single, low dose gestational exposure of IgG derived from individual MAU on their offspring's physical and social development.

  14. Development and validation of an indirect Enzyme-linked immunosorbent assay for the detection of antibodies against Schmallenberg virus in blood samples from ruminants. (United States)

    van der Heijden, H M J F; Bouwstra, R J; Mars, M H; van der Poel, W H M; Wellenberg, G J; van Maanen, C


    To detect Schmallenberg virus (SBV) infections in ruminants and to perform SBV epidemiological studies a cost-effective serological test is required. For these purposes an indirect whole virus Enzyme-linked Immunosorbent Assay (ELISA) for detection of SBV specific antibodies in ruminant blood samples was developed. Schmallenberg virus antigen was produced by propagation on Vero cells, partly purified and coated onto ELISA plates. The indirect ELISA procedure included the subsequent incubation of diluted samples, protein-G-HRP conjugate and TMB substrate solution. Net Optical Densities (OD) values were calculated and expressed as a sample to positive percentage (S/P%) by comparison of the average net OD with the OD of the positive control. Validation of this assay was performed using 633 samples from SBV-free sheep, goats and cattle, and 141 samples from SBV suspect ruminants. The diagnostic specificity was 98.8%. Test results of 86 ruminant serum samples using both the SBV-ELISA and an SBV virus neutralization test (VNT), designated as the gold standard serological test for SBV, showed good correlation: at an S/P cut-off of 15% only one VNT positive sample tested negative in the SBV ELISA. The diagnostic sensitivity of the ELISA, relative to the VNT, was 98.8% (95% CI: 93.3-100.0%). The ELISA showed a high repeatability (cv=6.5%) and reproducibility (100% agreement). It was concluded that this ELISA is a suitable test method for the detection of SBV antibodies in sera from cows, sheep and, possibly, goats.

  15. 正安县山羊主要疫病血清抗体检测报告%Testing Report of Goat Major Disease Serum Antibody in Zhengtm

    Institute of Scientific and Technical Information of China (English)

    朱小飞; 周碧君; 程振涛; 文明; 王开功; 崔亚兰; 罗意


    The purpose of this investigation was to understand the development trend of the main goat epidemics in Zhen'an country. Bengal precipitation test of Brucellosis(RPBT) , positive indirect hemagglutination, enzyme - linked immunosorbent assay(ELISA) were used to detect antibodies of goats which introduced to Zhen'an county, the survey including type O foot -and -mouth disease( O -FMD), type Asia- I foot- and -mouth disease( Asia [ -FMD) , contagious eaprine plneuropneumoniav(CCPP) , goatpox. The results show that the positive rate of immune antibodies on O -FMD Asia- I - FMD and goatpox were 79.42% , 81.18% and 99.58% , the level of un - immuned antibodies of brucellosis, mycolasa capricolum subspecies capri (Mmc) and myeolasa, ovipneumoniae (Mo)were 0%, 0% and 3.81% respectively. The findings should have important implication for health goats introduction, cultivate and propagation as well as goat husbandry guidance.%为了解正安县山羊主要疫病的发展趋势,通过虎红平板凝集试验、正向间接血凝试验、酶联免疫吸附试验等方法对正安县引进山羊进行布鲁氏杆菌病、O型口蹄疫、AsiaI型口蹄疫、山羊传染性胸膜肺炎、山羊痘等主要疫病血清抗体的检测。结果表明,O型口蹄疫、AsiaI型口蹄疫和山羊痘免疫抗体阳性率分别为79.42%、81.18%和99.58%,未免疫的布鲁氏杆菌病、羊传染性胸膜肺炎的丝状支原体山羊亚种和绵羊肺炎支原体未免疫抗体阳性率分别为0%、0%和3.81%。监测结果为山羊健康的引进、培育和扩繁提供了一些基础数据,对指导养羊生产有一定的意义。

  16. Dengue NS1 and prM antibodies increase the sensitivity of acute dengue diagnosis test and differentiate from Japanese encephalitis infection. (United States)

    Gowri Sankar, S; Balaji, T; Venkatasubramani, K; Thenmozhi, V; Dhananjeyan, K J; Paramasivan, R; Tyagi, B K; John Vennison, S


    Accurate and early diagnosis of dengue infection is essential for dengue case management. In outbreak conditions, it is essential to include two different tests to diagnose dengue and the choice depends on the number of days after the onset of illness in which the sample is collected. During the laboratory diagnosis of dengue in late acute and convalescent phase by MAC-ELISA, it is necessary to rule out possible cross reactions of closely related flavivirus, such as Japanese encephalitis virus which is commonly co-circulating. In the present investigation, the usefulness of dengue virus NS1 and prM antibodies in diagnosing and differentiating dengue from Japanese encephalitis infection was assessed using samples collected during out-breaks. It was shown here that, detection of antibodies against dengue NS1 and prM proteins increases the sensitivity of dengue diagnosis until 15days. Moreover, detection of antibodies against both proteins was able to differentiate dengue from Japanese encephalitis infection.

  17. Development of a Generic Microfluidic Device for Simultaneous Detection of Antibodies and Nucleic Acids in Oral Fluids

    Directory of Open Access Journals (Sweden)

    Zongyuan Chen


    Full Text Available A prototype dual-path microfluidic device (Rheonix CARD capable of performing simultaneously screening (antigen or antibody and confirmatory (nucleic acid detection of pathogens is described. The device fully integrates sample processing, antigen or antibody detection, and nucleic acid amplification and detection, demonstrating rapid and inexpensive “sample-to-result” diagnosis with performance comparable to benchtop analysis. For the chip design, a modular approach was followed allowing the optimization of individual steps in the sample processing process. This modular design provides great versatility accommodating different disease targets independently of the production method. In the detection module, a lateral flow (LF protocol utilizing upconverting phosphor (UCP reporters was employed. The nucleic acid (NA module incorporates a generic microtube containing dry reagents. Lateral flow strips and PCR primers determine the target or disease that is diagnosed. Diagnosis of HIV infection was used as a model to investigate the simultaneous detection of both human antibodies against the virus and viral RNA. The serological result is available in less than 30 min, and the confirmation by RNA amplification takes another 60 min. This approach combines a core serological portable diagnostic with a nucleic acid-based confirmatory test.

  18. SLAC physicists develop test for string theory

    CERN Multimedia

    Yajnik, Juhi


    "Under certain conditions, string theory solves many of the questions wracking the minds of physicists, but until recently it had one major flaw - it could not be tested. SLAC (Stanford Linear Accelerator Center) scientists have found a way to test this revolutionary theory, which posits that there are 10 or 11 dimensions in our universe" (1 page)

  19. Current Research/Development in Language Testing. (United States)

    Oller, John W., Jr.

    A discussion of language testing looks at the relationship between the processes of language learning and language testing, particularly from the point of view of pragmatics theory. It outlines some of the theory of Charles Sanders Pierce and its role in the evolution of linguistic theory, as well as the work of other theorists concerning the…

  20. Frequencies and Specificities of “Enzyme-Only” Detected Erythrocyte Alloantibodies in Patients Hospitalized in Austria: Is an Enzyme Test Required for Routine Red Blood Cell Antibody Screening?

    Directory of Open Access Journals (Sweden)

    Dietmar Enko


    Full Text Available The aim of this study was to determine the frequencies and specificities of “enzyme-only” detected red blood cell (RBC alloantibodies in the routine antibody screening and antibody identification in patients hospitalized in Austria. Routine blood samples of 2420 patients were investigated. The antibody screening was performed with a 3-cell panel in the low-ionic strength saline- (LISS- indirect antiglobulin test (IAT and with an enzyme-pretreated (papain 3-cell panel fully automated on the ORTHO AutoVue Innova System. The antibody identification was carried out manually with an 11-cell panel in the LISS-IAT and with an enzyme-pretreated (papain 11-cell panel. In total 4.05% (n=98 of all patients (n=2420 had a positive RBC antibody screening result. Of them 25.51% (25/98 showed “enzyme-only” detected specific or nonspecific RBC alloantibodies. Rhesus and Lewis system antibodies were found the only specificities of “enzyme-only” RBC alloantibodies: all in all 4.8% (4/98 were detected with anti-E, 3.06% (3/98 with anti-Lea, 3.06% (3/98 with anti-D after anti-D prophylaxis and 1.02% (1/98 with anti-e. In total, 14.29% (14/98 showed a nonspecific RBC alloantibody result with the enzyme test. The results of the present study demonstrate that a high number of unwanted positive reactions with the enzyme technique overshadows the detection of “enzyme-only” RBC alloantibodies. (Trial Registration: K-37-13.

  1. Antithyroid microsomal antibody (United States)

    ... to confirm the cause of thyroid problems, including Hashimoto thyroiditis . The test is also used to find ... positive test may be due to: Granulomatous thyroiditis Hashimoto thyroiditis High levels of these antibodies have also ...

  2. Accuracy of a point-of-care ELISA test kit for predicting the presence of protective canine parvovirus and canine distemper virus antibody concentrations in dogs. (United States)

    Litster, A L; Pressler, B; Volpe, A; Dubovi, E


    Canine parvovirus (CPV) and canine distemper virus (CDV) are highly infectious and often fatal diseases with worldwide distributions, and are important population management considerations in animal shelters. A point-of-care ELISA test kit is available to detect serum antibodies to CPV and CDV, and presumptively to predict protective status. The aim of this study was to determine the diagnostic accuracy of the test compared to CPV hemagglutination inhibition titers and CDV serum neutralization titers determined by a reference laboratory, using sera collected from dogs housed at animal shelters. The ELISA test was used under both field and laboratory conditions and duplicate specimens were processed using an extra wash step. The test kit yielded accurate results (CPV: sensitivity 92.3%, specificity 93.5%; CDV: sensitivity 75.7%, specificity 91.8%) under field conditions. CDV sensitivity was improved by performing the test under laboratory conditions and using an optical density (OD) meter (laboratory performed 94.0%; OD 88.1%). Point-of-care ELISA testing for serum CPV and CDV antibody titers was demonstrated to be a useful tool for determining antibody status when making decisions regarding the need for CPV and/or CDV vaccination and also in animal shelters for population management.

  3. An improved and robust DNA immunization method to develop antibodies against extracellular loops of multi-transmembrane proteins. (United States)

    Hazen, Meredith; Bhakta, Sunil; Vij, Rajesh; Randle, Steven; Kallop, Dara; Chiang, Vicki; Hötzel, Isidro; Jaiswal, Bijay S; Ervin, Karen E; Li, Bing; Weimer, Robby M; Polakis, Paul; Scheller, Richard H; Junutula, Jagath R; Hongo, Jo-Anne S


    Multi-transmembrane proteins are especially difficult targets for antibody generation largely due to the challenge of producing a protein that maintains its native conformation in the absence of a stabilizing membrane. Here, we describe an immunization strategy that successfully resulted in the identification of monoclonal antibodies that bind specifically to extracellular epitopes of a 12 transmembrane protein, multi-drug resistant protein 4 (MRP4). These monoclonal antibodies were developed following hydrodynamic tail vein immunization with a cytomegalovirus (CMV) promoter-based plasmid expressing MRP4 cDNA and were characterized by flow cytometry. As expected, the use of the immune modulators fetal liver tyrosine kinase 3 ligand (Flt3L) and granulocyte-macrophage colony-stimulating factor positively enhanced the immune response against MRP4. Imaging studies using CMV-based plasmids expressing luciferase showed that the in vivo half-life of the target antigen was less than 48 h using CMV-based plasmids, thus necessitating frequent boosting with DNA to achieve an adequate immune response. We also describe a comparison of plasmids, which contained MRP4 cDNA with either the CMV or CAG promoters, used for immunizations. The observed luciferase activity in this comparison demonstrated that the CAG promoter-containing plasmid pCAGGS induced prolonged constitutive expression of MRP4 and an increased anti-MRP4 specific immune response even when the plasmid was injected less frequently. The method described here is one that can be broadly applicable as a general immunization strategy to develop antibodies against multi-transmembrane proteins, as well as target antigens that are difficult to express or purify in native and functionally active conformation.

  4. Development of novel monoclonal antibodies that define differentiation stages of human stromal (mesenchymal) stem cells

    DEFF Research Database (Denmark)

    Andersen, Ditte Caroline; Kortesidis, Angela; Zannettino, Andrew C W;


    fewer differentiated alkaline phosphatase(+) cells compared to STRO-1(+/-)/Collagen VI(+) hMSC, suggesting that Collagen VI on the cell membrane exclusively defines differentiated MSCs. In conclusion, we have generated a panel of high quality antibodies to be used for characterization of MSCs...... of clonogenic hMSC from BMMNCs as single reagents. Using mass-spectrometric analysis, we identified the antigen recognised by DJ3 as CD44, whereas DJ9 and DJ18 recognized HLA-DRB1 and Collagen VI, respectively. The identified proteins were highly expressed throughout in vitro osteogenic- and adipogenic...... mice with hMSC, and by using a panel of subsequent screening methods. Flow cytometry analysis revealed that 83.5, 1.1, and 8.5% of primary cultures of hMSC were double positive for STRO-1 and either of DJ 3, 9, and 18, respectively. However, none of the three DJ antibodies allowed enrichment...

  5. Process Research and Development of Antibodies as Countermeasures for C. Botulinum (United States)


    using dihydrofolate reductase (dhfr) in CHO cells (Alt, et al., 1978; Urlaub and Chasin, 1980) and glutamine synthetase (GS) in NS0 (Cockett et al...CR, Yarranton GT. High level expression of tissue inhibitor of metalloproteinases in Chinese hamster ovary cells using glutamine synthetase gene...of a recombinant antibody from myeloma cells using a glutamine synthetase gene as an amplifiable selectable marker. Biotechnology (N Y). 1992 Feb;10

  6. Antibodies Against Human BLyS and APRIL Attenuate EAE Development in Marmoset Monkeys


    Jagessar, Anwar; Heijmans, Nicole; Bauer, J.; Blezer, Erwin; Laman, Jon; Migone, Thi-Sau; Devalaraja, Matt; Hart, Bert


    textabstractB lymphocyte stimulator (BLyS, also indicated as BAFF (B-cell activating factor) and CD257), and A Proliferation Inducing Ligand (APRIL, CD256) are two members of the TNF superfamily with a central role in B cell survival. Antibodies against these factors have potential therapeutic relevance in autoimmune inflammatory disorders with a proven pathogenic contribution of B cells, such as multiple sclerosis (MS). In the current study we performed a multi-parameter efficacy comparison ...

  7. Antibody Recognition of the Dengue Virus Proteome and Implications for Development of Vaccines (United States)


    acquired immunity to other dengue serotypes and in infants carrying subneutralizing maternal antibodies (20). As the overall effectiveness of the...microarray used for our study was comprised of the proteomes of all four dengue serotypes , consisting of the seven NS pro- teins and three structural...strains. We used a protein microarray encompassing representative proteomes of all four dengue serotypes to compare immune responses to two types of

  8. Development of next generation antivenoms based on mixtures of human antibodies

    DEFF Research Database (Denmark)

    Knudsen, Cecilie; Andersen, Mikael Rørdam; Harrison, Robert

    With an annual 150,000 deaths and countless amputations and disfigurements,snakebite envenoming is an ever-present threat in many parts of the rural tropicalworld. In sub-Saharan Africa, only 1-2% of victims are treated with antivenom,which is currently based on animal-derived antibodies. Due to ...... to their heterologousorigin, antivenoms often provoke serious side effects in human recipients, such asserum sickness and anaphylaxis, which in some cases leads to death....

  9. Development of therapeutic antibodies to G protein-coupled receptors and ion channels: Opportunities, challenges and their therapeutic potential in respiratory diseases. (United States)

    Douthwaite, Julie A; Finch, Donna K; Mustelin, Tomas; Wilkinson, Trevor C I


    The development of recombinant antibody therapeutics continues to be a significant area of growth in the pharmaceutical industry with almost 50 approved monoclonal antibodies on the market in the US and Europe. Therapeutic drug targets such as soluble cytokines, growth factors and single transmembrane spanning receptors have been successfully targeted by recombinant monoclonal antibodies and the development of new product candidates continues. Despite this growth, however, certain classes of important disease targets have remained intractable to therapeutic antibodies due to the complexity of the target molecules. These complex target molecules include G protein-coupled receptors and ion channels which represent a large target class for therapeutic intervention with monoclonal antibodies. Although these targets have typically been addressed by small molecule approaches, the exquisite specificity of antibodies provides a significant opportunity to provide selective modulation of these important regulators of cell function. Given this opportunity, a significant effort has been applied to address the challenges of targeting these complex molecules and a number of targets are linked to the pathophysiology of respiratory diseases. In this review, we provide a summary of the importance of GPCRs and ion channels involved in respiratory disease and discuss advantages offered by antibodies as therapeutics at these targets. We highlight some recent GPCRs and ion channels linked to respiratory disease mechanisms and describe in detail recent progress made in the strategies for discovery of functional antibodies against challenging membrane protein targets such as GPCRs and ion channels.

  10. Development of a monoclonal antibody against viral haemorrhagic septicaemia virus (VHSV) genotype IVa. (United States)

    Ito, T; Olesen, N J; Skall, H F; Sano, M; Kurita, J; Nakajima, K; Iida, T


    The viral haemorrhagic septicaemia virus (VHSV) comprises 4 major genotypes and a number of subtypes with, in most cases, distinct geographical distribution. A quick and simple detection method that can discriminate the different genotypes is desirable for a quick and more efficient prevention of the spread of genotypes to new geographical areas. A monoclonal antibody (MAb) against VHSV genotype IVa was produced, with the aim of providing a simple method of discriminating this genotype from the other VHSV genotypes (I, II, III and IVb). Balb/c mice were injected with purified VHSV-JF00Ehil (genotype IVa) from diseased farmed Japanese flounder. Ten hybridoma clones secreting monoclonal antibodies (MAbs) against VHSV were established. One of these, MAb VHS-10, reacted only with genotype IVa in indirect fluorescent antibody technique (IFAT) and ELISA. Using cell cultures that were transfected with each of the viral protein genes, it was shown that the MAb VHS-10 recognizes a nonlinear genotype IVa-specific epitope on the VHSV N-protein.

  11. Development and evaluation of a magnetic immunochromatographic test to detect Taenia solium, which causes taeniasis and neurocysticercosis in humans. (United States)

    Handali, Sukwan; Klarman, Molly; Gaspard, Amanda N; Dong, X Fan; Laborde, Ronald; Noh, John; Lee, Yeuk-Mui; Rodriguez, Silvia; Gonzalez, Armando E; Garcia, Hector H; Gilman, Robert H; Tsang, Victor C W; Wilkins, Patricia P


    Taeniasis/cysticercosis caused by Taenia solium is a frequent parasitic infection of the human brain in most of the world. Rapid and simple screening tools to identify taeniasis and cysticercosis cases are needed for control programs, mostly to identify tapeworm carriers which are the source of infection and need to be treated, or as tools for point-of-care case detection or confirmation. These screening assays should be affordable, reliable, rapid, and easy to perform. Immunochromatographic tests meet these criteria. To demonstrate proof of principle, we developed and evaluated two magnetic immunochromatographic tests (MICTs) for detection of human Taenia solium taeniasis antibodies (ES33-MICT) and neurocysticercosis antibodies (T24-MICT). These assays detected stage-specific antibodies by using two recombinant proteins, rES33 for detection of taeniasis antibodies and rT24H for detection of cysticercosis antibodies. The sensitivity and specificity of the ES33-MICT to detect taeniasis infections were 94.5% and 96%, respectively, and those of the T24-MICT to detect cases of human cysticercosis with two or more viable brain cysts were 93.9% and 98.9%, respectively. These data provide proof of principle that the ES33- and T24-MICTs provide rapid and suitable methods to identify individuals with taeniasis and cysticercosis.

  12. The development and validation of an immunoassay for the measurement of anti-thymidine phosphorylase antibodies in mouse and dog sera. (United States)

    Gasson, Charlotte; Levene, Michelle; Bax, Bridget E


    Erythrocyte encapsulated thymidine phosphorylase (EE-TP) is under development as an enzyme replacement therapy for mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), a fatal metabolic disorder resulting from an inherited deficiency of the enzyme thymidine phosphorylase. We report here the development and validation of a sensitive electrochemiluminescent (ECL) bridging immunoassay to support Good Laboratory Practice (GLP)-compliant preclinical safety studies of EE-TP in the mouse and dog. Affinity-purified rabbit anti-E. coli thymidine phosphorylase (TP) antibody was used as a calibrator standard with an effective working range of 2.5-7500 ng/mL. The minimum required dilution (MRD) for both mouse and dog sera was 1:10. The mean analytical recoveries for anti-TP antibodies spiked into serum at 70 ng/mL and 7000 ng/mL were 117.9% and 93.2%, respectively for mouse, and 112.0% and 104.3%, respectively for dog. The intra-assay precision (coefficient of variation, CV) ranged between 1.1% and 8.0% in mouse serum, and 1.9% and 2.5% in dog serum. Inter-assay precision ranged between -1.6% and 6.7% in mouse serum, and -13.0% and -2.5% in dog serum. Assay cut-point/screening cut-point correction factors were 201.37 and 44.4, respectively for mouse and dog sera. For future analysis of positive test samples, less than 37.12% (mouse) and 31.41% (dog) inhibition of the assay signal in the confirmation assay will confer anti-TP antibody specificity. Assay drift and hook effects (prozone) were not observed. The intra-assay and inter-assay accuracy for robustness were within ±20%.

  13. Development of monoclonal antibodies to human microsomal epoxide hydrolase and analysis of “preneoplastic antigen”-like molecules

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Hongying [Department of Microbiology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Yoshimura, Kazunori [Department of Physiology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Kobayashi, Nobuharu; Sugiyama, Kazuo [Department of Microbiology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Sawada, Jun-ichi; Saito, Yoshiro [Division of Biochemistry and Immunochemistry, National Institute of Health Sciences, Kamiyoga 1-18-1, Setagaya-ku, Tokyo 158-8501 (Japan); Morisseau, Christophe; Hammock, Bruce D. [Department of Entomology and Cancer Center, University of California, Davis, One Shields Avenue, Davis, CA 95616-8584 (United States); Akatsuka, Toshitaka, E-mail: [Department of Microbiology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan)


    Microsomal epoxide hydrolase (mEH) is a drug metabolizing enzyme which resides on the endoplasmic reticulum (ER) membrane and catalyzes the hydration of reactive epoxide intermediates that are formed by cytochrome P450s. mEH is also thought to have a role in bile acid transport on the plasma membrane of hepatocytes. It is speculated that efficient execution of such multiple functions is secured by its orientation and association with cytochrome P450 enzymes on the ER membrane and formation of a multiple transport system on the plasma membrane. In certain disease status, mEH loses its association with the membrane and can be detected as distinct antigens in the cytosol of preneoplastic foci of liver (preneoplastic antigen), in the serum in association with hepatitis C virus infection (AN antigen), or in some brain tumors. To analyze the antigenic structures of mEH in physiological and pathological conditions, we developed monoclonal antibodies against different portions of mEH. Five different kinds of antibodies were obtained: three, anti-N-terminal portions; one anti-C-terminal; and one, anti-conformational epitope. By combining these antibodies, we developed antigen detection methods which are specific to either the membrane-bound form or the linearized form of mEH. These methods detected mEH in the culture medium released from a hepatocellular carcinoma cell line and a glioblastoma cell line, which was found to be a multimolecular complex with a unique antigenic structure different from that of the membrane-bound form of mEH. These antibodies and antigen detection methods may be useful to study pathological changes of mEH in various human diseases. -- Highlights: ► Monoclonal antibodies against different portions of mEH were developed. ► They discriminate between the membrane-bound and the linearized forms of mEH. ► We analyze the antigenic structure of the altered form of mEH in tumor cells. ► Preneoplastic antigen is a multimolecular complex of mEH with

  14. Induction of antibodies reactive to cardiac myosin and development of heart alterations in cruzipain-immunized mice and their offspring. (United States)

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


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

  15. Comparative Evaluation of Native Antigens for the Development of Brucellosis Antibody Detection System

    Directory of Open Access Journals (Sweden)

    Yasmin Bano


    Full Text Available Brucellosis is a highly infectious zoonotic disease and an economically important infection of humans and livestock with a worldwide distribution. The main mode of transmission of this disease to humans is through the consumption of infected milk, milk products, and uncooked or raw meat. The present study was designed to prepare few native antigens, that is, sonicated antigen (SA, cell envelope (CE antigen, and freeze and thaw (FT antigen from Brucella abortus S99 culture and to test them in a highly sensitive and specific indirect enzyme-linked immunosorbent assay (I-ELISA in both a microtiter plate and a dot-blot format for the development of field-based diagnosis. All 50 suspected bovine samples were tested by plate as well as in dot ELISA formats for all the three antigens prepared. The CE antigen was found to be more suitable as it had the maximum agreement with the Rose Bengal plate agglutination test results followed by the SA and the least agreement was found with that of the FT antigen. This detection system in microtiter plates and a dot-blot format will be useful for the rapid screening of samples for the disease surveillance and routine diagnosis.

  16. Anti-smooth muscle antibody (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 ...

  17. Comparison of Buffered, Acidified Plate Antigen to Standard Serologic Tests for the Detection of Serum Antibodies to Brucella abortus in Elk (Cervus canadensis). (United States)

    Clarke, P Ryan; Edwards, William H; Hennager, Steven G; Block, Jean F; Yates, Angela M; Ebel, Eric; Knopp, Douglas J; Fuentes-Sanchez, Antonio; Jennings-Gaines, Jessica; Kientz, Rebecca L; Simunich, Marilyn


    Brucellosis (caused by the bacterium Brucella abortus) is a zoonotic disease endemic in wild elk (Cervus canadensis) of the Greater Yellowstone Ecosystem, US. Because livestock and humans working with elk or livestock are at risk, validated tests to detect the B. abortus antibody in elk are needed. Using the κ-statistic, we evaluated the buffered, acidified plate antigen (BAPA) assay for agreement with the results of the four serologic tests (card test [card], complement fixation test [CF], rivanol precipitation plate agglutination test [RIV], standard plate agglutination test [SPT]) that are approved by the US Department of Agriculture for the detection of the B. abortus antibody in elk. From 2006 to 2010, serum samples collected from elk within B. abortus-endemic areas (n = 604) and nonendemic areas (n = 707) and from elk culture-positive for B. abortus (n = 36) were split and blind tested by four elk serum diagnostic laboratories. κ-Values showed a high degree of agreement for the card (0.876), RIV (0.84), and CF (0.774) test pairings and moderate agreement for the SPT (0.578). Sensitivities for the BAPA, card, RIV, CF, and SPT were 0.859, 0.839, 0.899, 1.00, and 0.813, whereas specificities were 0.986, 0.993, 0.986, 0.98, and 0.968, respectively. The positive predictive values and the negative predictive values were calculated for 2.6%, 8.8%, and 16.2% prevalence levels. These findings suggest the BAPA test is a suitable screening test for the B. abortus antibodies in elk.

  18. Covalent immobilization of rabbit-antiaflatoxin-antibodies onto the poly-acrylamideacrylonitrile as well as hybrid material UREASIL and developing an optical immunosensor (United States)

    Slavova, M.; Georgieva-Nikolova, R.; Hristov, H.; Nikolova, M.


    The aim of this work is to describe a covalent immobilization of antibodies onto the poly- acrylamide-acrylonitrile or hybrid material UREASIL and creation of optical immunosensor for determination of aflatoxin Bl. For this purpose, mouse-anti-aflatoxin B1 antibodies with oxidized carbohydrate moieties were covalently immobilized on the membranes of polyacrylamide- polyacrylonitrile copolymer, as well as the hybrid material UREASIL. To determine the affinity> binding of the immobilized antibody with afatoxin Bl was used "sandwich" method. Associated with the immobilized antibody sought ingredients interact with a surplus of secondary' signal antibodies. The described method has been developed as a model system, which can easily be applied for the determination of aflatoxins in samples of different origin. To the best of our knowledge, this is the first study to show that in the establishment of biosensor was used hybrid material UREASIL.

  19. Development of a monoclonal antibody-based broad-specificity ELISA for fluroquinolone antibiotics in foods and molecular modeling studies of cross-reactive compounds (United States)

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

  20. Use of silver nanoparticles increased inhibition of cell-associated HIV-1 infection by neutralizing antibodies developed against HIV-1 envelope proteins

    Directory of Open Access Journals (Sweden)

    Garza Treviño Elsa N


    Full Text Available Abstract Background HIV/AIDS pandemic is a worldwide public health issue. There is a need for new approaches to develop new antiviral compounds or other therapeutic strategies to limit viral transmission. The envelope glycoproteins gp120 and gp41 of HIV are the main targets for both silver nanoparticles (AgNPs and neutralizing antibodies. There is an urgency to optimize the efficiency of the neutralizing antibodies (NABs. In this study, we demonstrated that there is an additive effect between the four NABs and AgNPs when combined against cell-associated HIV-1 infection in vitro Results Four NABs (Monoclonal antibody to HIV-1 gp41 126-7, HIV-1 gp120 Antiserum PB1 Sub 2, HIV-1 gp120 Antiserum PB1, HIV-1 gp120 Monoclonal Antibody F425 B4e8 with or without AgNPs of 30-50 nm in size were tested against cell free and cell-associated HIVIIIB virus. All NABs inhibited HIV-1 cell free infection at a dose response manner, but with AgNPs an antiviral additive effect was not achieved Although there was no inhibition of infection with cell-associated virus by the NABs itself, AgNPs alone were able to inhibit cell associated virus infection and more importantly, when mixed together with NABs they inhibited the HIV-1 cell associated infection in an additive manner. Discussion The most attractive strategies to deal with the HIV problem are the development of a prophylactic vaccine and the development of effective topical vaginal microbicide. For two decades a potent vaccine that inhibits transmission of infection of HIV has been searched. There are vaccines that elicit NABs but none of them has the efficacy to stop transmission of HIV-1 infection. We propose that with the addition of AgNPs, NABs will have an additive effect and become more potent to inhibit cell-associated HIV-1 transmission/infection. Conclusions The addition of AgNPs to NABs has significantly increased the neutralizing potency of NABs in prevention of cell-associated HIV-1 transmission

  1. [VGKC-complex antibodies]. (United States)

    Watanabe, Osamu


    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).

  2. Test the Artifact - Develop the Organization

    DEFF Research Database (Denmark)

    Bossen, Claus


    Objective and methods: The paper aims to develop further insights into the process of implementationof IT in health care by describing findings from a study of a trial implementationof a newly developed electronic medication plan (EMP) in three hospitals in a county in Denmark.A sociotechnical...

  3. A comparison of titers of anti-Brucella antibodies of naturally infected and healthy vaccinated cattle by standard tube agglutination test, microtiter plate agglutination test, indirect hemagglutination assay, and indirect enzyme-linked immunosorbent assay

    Directory of Open Access Journals (Sweden)

    Anju Mohan


    Full Text Available Aim: We determined the antibody response in cattle naturally infected with brucellosis and normal healthy adult cattle vaccinated during calf hood with strain 19. Materials and Methods: The antibody titers were measured by standard tube agglutination test (STAT, microtiter plate agglutination test (MAT, indirect hemagglutination assay (IHA, and indirect enzyme-linked immunosorbent assay (iELISA as per standard protocols. Results: The mean STAT titers were 1.963±0.345 in infected cattle and 1.200±0.155 in healthy vaccinated cattle. The difference was extremely significant (p<0.0001. The mean MAT titers were 2.244±0.727 in infected cattle and 1.200±0.155 in healthy vaccinated cattle. The difference was very significant (p<0.005. The mean IHA titers in infected cattle were 2.284±0.574, and those in healthy vaccinated cattle were 1.200±0.155. The difference was extremely significant (p=0.0002. However, the difference in mean iELISA titers of infected cattle (1.3678±0.014 and healthy vaccinated cattle (1.367±0.014 was non-significant. The infected animals showed very high titers of agglutinating antibodies compared to the vaccinated animals. However, it cannot be ascertained whether these antibodies are due to vaccine or response to infection. Since the infected animals had been vaccinated earlier, the current infection may suggest that vaccination was unable to induce protective levels of antibody. The heightened antibody response after infection may also indicate a secondary immune response to the antigens common to the vaccine strain and wild Brucella organisms. Conclusion: The brucellosis infected animals showed very high titers of agglutinating antibodies compared to the vaccinated animals.

  4. Hypersonic Inflatable Aerodynamic Decelerator Ground Test Development (United States)

    Del Corso, Jospeh A.; Hughes, Stephen; Cheatwood, Neil; Johnson, Keith; Calomino, Anthony


    Hypersonic Inflatable Aerodynamic Decelerator (HIAD) technology readiness levels have been incrementally matured by NASA over the last thirteen years, with most recent support from NASA's Space Technology Mission Directorate (STMD) Game Changing Development Program (GCDP). Recently STMD GCDP has authorized funding and support through fiscal year 2015 (FY15) for continued HIAD ground developments which support a Mars Entry, Descent, and Landing (EDL) study. The Mars study will assess the viability of various EDL architectures to enable a Mars human architecture pathfinder mission planned for mid-2020. At its conclusion in November 2014, NASA's first HIAD ground development effort had demonstrated success with fabricating a 50 W/cm2 modular thermal protection system, a 400 C capable inflatable structure, a 10-meter scale aeroshell manufacturing capability, together with calibrated thermal and structural models. Despite the unquestionable success of the first HIAD ground development effort, it was recognized that additional investment was needed in order to realize the full potential of the HIAD technology capability to enable future flight opportunities. The second HIAD ground development effort will focus on extending performance capability in key technology areas that include thermal protection system, lifting-body structures, inflation systems, flight control, stage transitions, and 15-meter aeroshell scalability. This paper presents an overview of the accomplishments under the baseline HIAD development effort and current plans for a follow-on development effort focused on extending those critical technologies needed to enable a Mars Pathfinder mission.


    Directory of Open Access Journals (Sweden)

    Y. M. Harsono


    Full Text Available The Communicative Approach of teaching English in senior high school in Indonesia has been adopted since the implementation of The 1984 Curriculum, but the tests–the communicative language tests–(CL Tests have not been developed and used properly. The objective of the study is to develop CL Tests for senior high school. The procedure of conducting the study consists of three major steps, that is, identifying the objectives, developing the test specification, and developing the CL Tests. The development of the CL Tests in detail consists of fifteen sub-steps from determining what language skills tested, selecting the suitable source materials, up to rewriting the CL Tests to be used as CL Tests alternative for senior high school. The results of the test development reveal that there are fifteen CL Tests consisting of three tests of listening, three reading, three speaking, and three writing tests. The whole tests have construct and content validity, no complete evidence of concurrent validity with report marks and semester test scores, high to very high inter-rater reliability, and no complete practicality.

  6. Development of a Rapid Qualitative Assay for Determining Elevated Antibody Levels to Periodontopathic Organisms (United States)


    another report, showed no elevation in IgM or IgA in these patients, with some-elevation of total~lgG (Rahney et’aL. 1981)’. Murray & Genco (1980) found...leukotoxic activity compared to 24% of normal, 39%of adult periodontitis,.,and 38% of ANUG sera. Genco et at. (1980b) found that.89% of LJP patients...Aactinomycetemcomitans have been notedin patients with rapidly progressive disease ( Genco et al. 1985). Theserum antibody response in adult periodontitis is more

  7. Development of murine monoclonal antibodies for the immunohistochemical diagnosis of systemic bovine aspergillosis

    DEFF Research Database (Denmark)

    Jensen, H.E.; Aalbaek, B.; Lind, Peter


    Murine monoclonal antibodies (MAbs) against water-soluble somatic antigens (WSSA) and the wall fraction (WF) from Aspergillus fumigatus were produced by fusion of splenocytes from immunized BALB/c mice with mouse myeloma X63-Ag 8.653 cells. The supernatants of in vitro cultured hybridomas were in.......e., aspergillosis was diagnosed. The characteristics of the 2 MAbs (MAb-WF-AF-1 and-2) raised against the WF of A. fumigatus in ELISA and immunoblotting and immunohistochemical assays justify their application for the in situ diagnosis of systemic aspergillosis of cattle....

  8. [New antibodies in cancer treatment]. (United States)

    Pestalozzi, B C; Knuth, A


    Since the development of hybridoma technology in 1975 monoclonal antibodies with pre-defined specificity can be produced. Only twenty years later did it become possible to make therapeutic use of monoclonal antibodies in oncology. To this end it was necessary to attach the antigen-binding site of a mouse antibody onto the scaffold of a human antibody molecule. Such chimeric or "humanized" antibodies may be used in passive immunotherapy without eliciting an immune response. Rituximab and trastuzumab are such humanized antibodies. They are used today routinely in the treatment of malignant lymphoma and breast cancer, respectively. These antibodies are usually used in combination with conventional cytostatic anticancer drugs.

  9. Engineering antibodies for cancer therapy. (United States)

    Boder, Eric T; Jiang, Wei


    The advent of modern antibody engineering has led to numerous successes in the application of these proteins for cancer therapy in the 13 years since the first Food and Drug Administration approval, which has stimulated active interest in developing more and better drugs based on these molecules. A wide range of tools for discovering and engineering antibodies has been brought to bear on this challenge in the past two decades. Here, we summarize mechanisms of monoclonal antibody therapeutic activity, challenges to effective antibody-based treatment, existing technologies for antibody engineering, and current concepts for engineering new antibody formats and antibody alternatives as next generation biopharmaceuticals for cancer treatment.

  10. Guide to good practices for the development of test items

    Energy Technology Data Exchange (ETDEWEB)



    While the methodology used in developing test items can vary significantly, to ensure quality examinations, test items should be developed systematically. Test design and development is discussed in the DOE Guide to Good Practices for Design, Development, and Implementation of Examinations. This guide is intended to be a supplement by providing more detailed guidance on the development of specific test items. This guide addresses the development of written examination test items primarily. However, many of the concepts also apply to oral examinations, both in the classroom and on the job. This guide is intended to be used as guidance for the classroom and laboratory instructor or curriculum developer responsible for the construction of individual test items. This document focuses on written test items, but includes information relative to open-reference (open book) examination test items, as well. These test items have been categorized as short-answer, multiple-choice, or essay. Each test item format is described, examples are provided, and a procedure for development is included. The appendices provide examples for writing test items, a test item development form, and examples of various test item formats.

  11. ITCS Test Strip Development and Certification (United States)

    Carrigan, Caitlin; Adam, Niklas; Pickering, Karen; Gazda, Daniel; Piowaty, Hailey


    Internal coolant loops used for International Space Station thermal control must be periodically monitored for system health, including pH, biocide levels and any indication of ammonia. The presence of ammonia, possible via a microleak in the interface between the internal and external thermal control systems, could be a danger to the crew. The Internal Thermal Control System (ITCS) Sampling Kit uses test strips as a colorimetric indicator of pH and concentrations of biocide and free ammonia. This paper describes the challenges in designing an ammonia colorimetric indicator in a variable pH environment, as well as lessons learned, ultimately resulting in a robust test strip to indicate a hazardous ammonia leak.

  12. Selection of Antigens and Development of Prototype Tests for Point-of-Care Leprosy Diagnosis▿ † (United States)

    Duthie, Malcolm S.; Ireton, Greg C.; Kanaujia, Ganga V.; Goto, Wakako; Liang, Hong; Bhatia, Ajay; Busceti, Jean Marie; Macdonald, Murdo; Neupane, Kapil Dev; Ranjit, Chaman; Sapkota, Bishwa Raj; Balagon, Marivic; Esfandiari, Javan; Carter, Darrick; Reed, Steven G.


    Leprosy can be a devastating chronic infection that causes nerve function impairment and associated disfigurement. Despite the recent reduction in the number of registered worldwide leprosy cases as a result of the widespread use of multidrug therapy, the number of new cases detected each year remains relatively stable. The diagnosis of leprosy is currently based on the appearance of clinical signs and requires expert clinical, as well as labor-intensive and time-consuming laboratory or histological, evaluation. For the purpose of developing an effective, simple, rapid, and low-cost diagnostic alternative, we have analyzed the serologic antibody response to identify Mycobacterium leprae proteins that are recognized by leprosy patients. More than 100 recombinant antigens were analyzed in a protein array format to select those with discriminatory properties for leprosy diagnosis. As expected, multibacillary leprosy patients recognized more antigens with stronger antibody responses than paucibacillary leprosy patients. Our data indicate, however, that multibacillary patients can be distinguished from paucibacillary patients, and both of these groups can be segregated from endemic control groups. We went on to confirm the diagnostic properties of antigens ML0405 and ML2331 and the LID-1 fusion construct of these two proteins by enzyme-linked immunosorbent assay. We then demonstrated the performance of these antigens in rapid test formats with a goal of developing a point-of-care diagnostic test. A serological diagnostic test capable of identifying and allowing treatment of leprosy could reduce transmission, prevent functional disabilities and stigmatizing deformities, and facilitate leprosy eradication. PMID:18716007

  13. "Unconventional" Neutralizing Activity of Antibodies Against HIV

    Institute of Scientific and Technical Information of China (English)


    Neutralizing antibodies are recognized to be one of the essential elements of the adaptive immune response that must be induced by an effective vaccine against HIV. However, only a limited number of antibodies have been identified to neutralize a broad range of primary isolates of HIV-1 and attempts to induce such antibodies by immunization were unsuccessful. The difficulties to generate such antibodies are mainly due to intrinsic properties of HIV-1 envelope spikes, such as high sequence diversity, heavy glycosylation, and inducible and transient nature of certain epitopes. In vitro neutralizing antibodies are identified using "conventional" neutralization assay which uses phytohemagglutinin (PHA)-stimulated human PBMCs as target cells. Thus, in essence the assay evaluates HIV-1 replication in CD4+ T cells. Recently, several laboratories including us demonstrated that some monoclonal antibodies and HIV-1-specific polyclonal IgG purified from patient sera, although they do not have neutralizing activity when tested by the "conventional" neutralization assay, do exhibit potent and broad neutralizing activity in "unconventional" ways. The neutralizing activity of these antibodies and IgG fractions is acquired through post-translational modifications, through opsonization of virus particles into macrophages and immature dendritic cells (iDCs), or through expression of antibodies on the surface of HIV-1-susceptible cells. This review will focus on recent findings of this area and point out their potential applications in the development of preventive strategies against HIV.

  14. Clinical appraisal of patients and detection of serum antibodies by ELISA and CIA tests in late periods of Trichinella sp. invasion

    Directory of Open Access Journals (Sweden)

    Kociecka W.


    Full Text Available Results of our studies using ELISA and competitive inhibition assay (CIA tests fully confirmed the previously experienced trichinellosis and reflected persistent stimulation of antibody production due to the antigen release from Trichinella larvae, which had survived longer and undergone gradual destruction in the muscles. The studies proved that the tests complement each other, yielding concordant results in 86.7 % of cases. Due to its higher specificity, the CIA test can help in interpreting pathological signs/symptoms and in evaluating humoral response activity at late and distant in time periods following the invasion.

  15. Development of monoclonal antibodies (MAbs) to feline interferon (fIFN)-γ as tools to evaluate cellular immune responses to feline infectious peritonitis virus (FIPV). (United States)

    Satoh, Ryoichi; Kaku, Ayumi; Satomura, Megumi; Kohori, Michiyo; Noura, Kanako; Furukawa, Tomoko; Kotake, Masako; Takano, Tomomi; Hohdatsu, Tsutomu


    Feline infectious peritonitis virus (FIPV) can cause a lethal disease in cats, feline infectious peritonitis (FIP). The antibody-dependent enhancement (ADE) of FIPV infection has been recognised in experimentally infected cats, and cellular immunity is considered to play an important role in preventing the onset of FIP. To evaluate the importance of cellular immunity for FIPV infection, monoclonal antibodies (MAbs) against feline interferon (fIFN)-γ were first created to establish fIFN-γ detection systems using the MAbs. Six anti-fIFN-γ MAbs were created. Then, the difference in epitope which those MAbs recognise was demonstrated by competitive enzyme-linked immunosorbent assay (ELISA) and IFN-γ neutralisation tests. Detection systems for fIFN-γ (sandwich ELISA, ELISpot assay, and two-colour flow cytometry) were established using anti-fIFN-γ MAbs that recognise different epitopes. In all tests, fIFN-γ production from peripheral blood mononuclear cells (PBMCs) obtained from cats experimentally infected with an FIPV isolate that did not develop the disease was significantly increased by heat-inactivated FIPV stimulation in comparison with medium alone. Especially, CD8(+)fIFN-γ(+) cells, but not CD4(+)fIFN-γ(+) cells, were increased. In contrast, fIFN-γ production from PBMCs isolated from cats that had developed FIP and specific pathogen-free (SPF) cats was not increased by heat-inactivated FIPV stimulation. These results suggest that cellular immunity plays an important role in preventing the development of FIP. Measurement of fIFN-γ production with the anti-fIFN-γ MAbs created in this study appeared to be useful in evaluating cellular immunity in cats.

  16. Development and evaluation of the rVP-ELISA for detection of antibodies against porcine parvovirus. (United States)

    Kong, Miaomiao; Peng, Yonggang; Cui, Yuchao; Chang, Tiecheng; Wang, Xiaoling; Liu, Zhaoxia; Liu, Yonggang; Zhu, Yu; Luo, Yakun; Tang, Qinghai; Feng, Li; Cui, Shangjin


    The gene encoding the VP2 protein of porcine parvovirus (PPV) was expressed in an insect-baculovirus system. The recombinant (r) VP2 was similar antigenically/functionally to the native capsid protein as demonstrated by hemagglutination (HA), Western blotting using PPV positive sera. The purified rVP2 proteins were used as coating antigen to establish a rVP-ELISA method for detection of PPV positive and negative sera from pigs. The optimal operating conditions of the rVP-ELISA were: the concentration of rVP2 proteins coated on the wells was 2 μg/mL; the diluted concentration of serum was 1: 150 and that of the enzyme-labeled antibody was 1: 6000. A total of 596 sera were detected by this assay, and the average positive rate was 87%. Compared with France LSI kit, the result showed that the coincidence rate was 96.7%. In conclusion, the rVP2-ELISA is a sensitive and specific method for detecting antibodies against PPV.

  17. Development of a mouse monoclonal antibody against the chondroitin sulfate-protein linkage region derived from shark cartilage. (United States)

    Akatsu, Chizuru; Fongmoon, Duriya; Mizumoto, Shuji; Jacquinet, Jean-Claude; Kongtawelert, Prachya; Yamada, Shuhei; Sugahara, Kazuyuki


    Glycosaminoglycans (GAGs) like chondroitin sulfate (CS) and heparan sulfate (HS) are synthesized on the tetrasaccharide linkage region, GlcAbeta1-3Galbeta1-3Galbeta1-4Xylbeta1-O-Ser, of proteoglycans. The Xyl can be modified by 2-O-phosphate in both CS and HS, whereas the Gal residues can be sulfated at C-4 and/or C-6 in CS but not in HS. To study the roles of these modifications, monoclonal antibodies were developed against linkage glycopeptides of shark cartilage CS proteoglycans, and one was characterized in detail. This antibody bound hexa- and pentasaccharide-peptides more strongly than unsaturated tetrasaccharide-peptides with the unnatural fourth sugar residue (unsaturated hexuronic acid), suggesting the importance of the fifth and/or fourth saccharide residue GalNAc-5 and/or GlcA-4. Its reactivity was not affected by treatment with chondro-4-sulfatase or alkaline phosphatase, suggesting that 4-O-sulfate on the Gal residues and 2-O-phosphate on the Xyl residue were not recognized. Treatment with weak alkali to cleave the Xyl-Ser linkage completely abolished the binding activity, suggesting the importance of the peptide moiety of the hexasaccharide-peptide for the binding. Based on the amino acid composition and matrix-assisted laser desorption ionization time-of-flight mass spectrometry analyses, it was revealed that the peptide moiety is composed of four amino acids, Ser, Pro, Gly, and Glu. Furthermore, the antibody stained wild-type CHO cells significantly, but much weakly mutant cells deficient in xylosyl- or galactosyltransferase-I required for the biosynthesis of the linkage region. These results suggest that the antibody recognizes the structure GalNAc(+/-6-O-sulfate)-GlcA-Gal-Gal-Xyl-Ser-(Pro, Gly, Glu). The antibody will be a useful tool for investigating the significance of the linkage region in the biosynthesis and/or intracellular transport of different GAG chains especially since such tools to study the linkage region are lacking.

  18. Humoral Immune Response Kinetics in Philander opossum and Didelphis marsupialis Infected and Immunized by Trypanosoma cruzi Employing an Immunofluorescence Antibody Test

    Directory of Open Access Journals (Sweden)

    Ana Paula Legey


    Full Text Available Philander opossum and Didelphis marsupialis considered the most ancient mammals and an evolutionary success, maintain parasitism by Trypanosoma cruzi without developing any apparent disease or important tissue lesion. In order to elucidate this well-balanced interaction, we decided to compare the humoral immune response kinetics of the two didelphids naturally and experimentally infected with T. cruzi and immunized by different schedules of parasite antigens, employing an indirect fluorescence antibody test (IFAT. Both didelphids responded with high serological titers to different immunization routes, while the earliest response occurred with the intradermic route. Serological titers of naturally infected P. opossum showed a significant individual variation, while those of D. marsupialis remained stable during the entire follow-up period. The serological titers of the experimentally infected animals varied according to the inoculated strain. Our data suggest that (1 IFAT was sensitive for follow-up of P. opossum in natural and experimental T. cruzi infections; (2 both P. opossum and D. marsupialis are able to mount an efficient humoral immune response as compared to placental mammals; (3 experimentally infected P. opossum and D. marsupialis present distinct patterns of infection, depending on the subpopulation of T. cruzi, (4 the differences observed in the humoral immune responses between P. opossum and D. marsupialis, probably, reflect distinct strategies selected by these animals during their coevolution with T. cruzi.

  19. Testing pigs of non-technified rearing farms for serum antibodies against Taenia solium in a region of the state of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Gabriel A.M. Rossi


    Full Text Available Abstract: Taenia solium is a zoonotic tapeworm of great importance in developing countries, due to the occurrence of human taeniasis and cysticercosis. Pigs have an important role in the biological cycle of the parasite as intermediate hosts. The scientific literature has been describing risk factors associated with the occurrence of this disease that must be avoided in countries with poor sanitation, in order to reduce the exposure of swine to the parasite eggs. This research focused on testing pigs of non-technified rearing farms for serum antibodies against Taenia solium in the region of Jaboticabal municipality, in the state of São Paulo, Brazil. The found prevalence was 6.82% (CI 95% 4.18 - 9.45 at animal level and 28.87% (CI 95% 16.74 - 40.40 at herd level. These figures are probably associated with low technification adoption during animal rearing in the studied area, which increased the exposure of the animals to risk factors associated with the occurrence of Taenia solium complex. The results found based on serological evidences of swine cysticercosis in the studied region serves as a warning to public sanitary authorities to improve public health and control T. solium.

  20. Development of a monoclonal antibody-based immunoassay for the detection and quantification of Anguillospora longissima colonizing leaf material.


    Bermingham, S; Dewey, F. M.; Maltby, L


    Monoclonal antibodies (MAbs) to the aquatic hyphomycete Anguillospora longissima were raised in mice by using a coimmunization program. A cell line was raised that produced a MAb of the immunoglobulin M class that was specific for A. longissima both in an enzyme-linked immunosorbent assay (ELISA) and by immunofluorescence but that did not recognize other members of the aquatic hyphomycetes. This MAb (AL-HH8c) was used to develop a quantitative ELISA in vitro. The antigen recognized by AL-HH8c...

  1. Development and Testing of Living Skin Equivalent. (United States)


    Model a) The use of Isografts in an inbred strain of rats. In a preliminary series of experiments the potential use of Fischer strain rats has been...tested by preparing a series of isografts made by grafting skin equivalents with cells from female donors to male hosts. On the average, wound...Autograft--rat 4 1 4 3 5 17 Autograft--rabbit 6 3 1 1 11 Isograft --rat 37 13 13 1 64 Allo fib., iso ker--rat 15 12 3 30 Allo fib, iso ker--rab 8 6 14 Iso

  2. Guidebook for Developing Criterion-Referenced Tests (United States)


    used at this level include: *Enabling Objectives 6 Knowledges e Skills e intnrmediate Objectives eLearning Elements (mental, physical, phone. The "product" sought is an orerational radio/telephone unit. "Process" information which might be noted includes style of work, care...individual work styles * Give order to begin e Adherence to standard procedures " Etc . Sc9r inq lUse of Scores 0 0ur ing or after test as per S.eC i f i

  3. Development and evaluation of diagnostic tests for the serological diagnosis of brucellosis in swine

    Directory of Open Access Journals (Sweden)

    Tiziana Di Febo


    Full Text Available A competitive enzyme-linked immunosorbent assay (c-ELISA, an indirect ELISA (i-ELISA and a dissociation-enhanced lanthanide fluorescence immunoassay (DELFIA were developed to test for antibodies to Brucella suis in pig and wild boar sera. An anti-Brucella-LPS monoclonal antibody (MAb 4B5A (c-ELISA and DELFIA and an anti-swine IgG monoclonal antibody (MAb 10C2G5 (i-ELISA were used for the three assays. The specificity (Sp and sensitivity (Se of the assays gave the following results: Se and Sp = 100% at a cut-off value of 61.0% (B/B0% for c-ELISA; Sp = 99.1% and Se = 100% at a cut-off value of 21.7% (percentage positivity: PP% for i-ELISA; Sp = 91.0% and Se = 75% at a cut-off value of 37.0% (B/B0% for DELFIA. In addition, the performance of a commercial fluorescence polarisation assay (FPA, standardised for bovine sera, was evaluated in swine sera. The specificity and sensitivity obtained were both 100% at a cut-off value of 99.5 (millipolarisation unit values. These results suggest that the combination of c-ELISA, i-ELISA and FPA can be used to improve the serological diagnosis of swine brucellosis.

  4. Skin autoreactivity in Hashimoto's thyroiditis patients without urticaria: autologous serum skin test positivity correlation with thyroid antibodies, sonographical volume and grading. (United States)

    Turkoglu, Zafer; Zindanci, Ilkin; Turkoglu, Ozlem; Can, Burce; Kavala, Mukaddes; Tamer, Gonca; Ulucay, Vasfiye; Akyer, Erdal


    Recent studies have shown an association between anti-thyroid antibodies and autologous serum skin test (ASST) positive urticaria patients. However, a connection between thyroid and this reliable skin test for mast cell autoreactivity, ASST, has not been reported yet. We investigated ASST in patients with Hashimoto's thyroiditis (HT) without urticaria and compared the results with laboratory and sonographical findings of HT. 154 HT patients, 100 healthy volunteers without HT as a first control group and 46 patients with multinodular goitre but without autoimmune thyroid disease as a second control group underwent testing with ASST. ASST was applied to these groups according to two criteria, first as ASST(new): autologous serum red wheal response 1.5 mm bigger than negative control; second as ASST(old): serum red wheal response 5 mm bigger than negative control accepted as positive. Free triiodothyronine (fT3), free thyroxine (fT4), thyroid-stimulating hormone (TSH), thyroid peroxidase antibody (anti-TPO) and thyroglobulin antibody (anti-Tg) levels were measured. ASST(old), ASST(new) scored positive in 51.3-60.4% of HT patients, with statistically significant differences. Thyroid volume grades were inversely proportional with ASST(old) and (new) positivity. Moderate (+) titers of anti-Tg in ASST(old) and (new) (+) cases were significantly higher than the same titers of anti-Tg in ASST(old) and (new) (-) cases. The prevalence of ASST positivity in HT patients was not affected by the following factors: gender, age at screening, laboratory measurements of thyroid function tests, anti-TPO antibodies and thyroid ultrasound (US) echogenicity. Positivity of ASST in HT has shown that there is a skin mast cell autoreactivity in HT patients independent of autoreactive chronic urticaria (ACU).

  5. Development of testing techniques for mine fan performance

    Institute of Scientific and Technical Information of China (English)

    WU Zheng-yan; JIANG Shu-guang; PENG Dan-ren


    Three progressive stages of testing techniques are elaborated, which are entirely manual operating, taking separate instruments testing and computer program controlling. The testing method and principle are detailed based on the testing process for meteorological parameters, air pressure, air quality and rotating velocity. And every testing technique is analyzed. Finally, the technique outlook is viewed. All this plays a leading role in development of the testing techniques.


    Energy Technology Data Exchange (ETDEWEB)

    Andrew W. Wang


    The Alternative Fuels Field Test Unit (AFFTU) is a portable laboratory designed specifically to provide on-site evaluation of potential feedstocks for processes that produce alternative fuels from indigenous raw materials such as coal, natural gas or environmentally disadvantaged carbonaceous feedstocks. Since conversion of these raw materials into feed gas streams can produce a variety of bulk gas compositions, which furthermore can contain a myriad of trace components, it is necessary to evaluate each new feedstock on an individual basis. While it is possible to prepare blended gas mixtures to simulate the bulk composition of a known feedstock, it is neither possible nor cost-effective to simulate adequately the variety of trace chemicals present in that feedstock--some of which may not even be detected by routine analysis. Additionally, the transient composition of the gas during upsets or routine process changes may have an impact on the proposed process that is not foreseen in standard design. To address these concerns, the AFFTU was constructed with the following experimental capabilities: (1) A state-of-the-art gas chromatograph system to perform semi-continuous monitoring of both bulk composition and the concentration of key trace poisons down to one part per billion (ppb). (2) A 30-mL reactor system that can accept up to two feed streams from the customer, allowing a true life test with the actual gas projected for use in the proposed facility. (3) A manifold of four adsorbent beds, located upstream of the reactor, which permits the testing of adsorbents for the removal of contaminants from the feed stream. The effectiveness of these adsorbents may be evaluated either by analysis of the gas upstream and downstream of the bed (or at an intermediate point within the bed) or by observing the impact of the presence or absence of that bed on the actual stability of the catalyst activity. To achieve portability, the AFFTU was constructed in a commercial 48-foot

  7. 40 CFR 766.16 - Developing the analytical test method. (United States)


    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Developing the analytical test method... SUBSTANCES CONTROL ACT DIBENZO-PARA-DIOXINS/DIBENZOFURANS General Provisions § 766.16 Developing the analytical test method. Because of the matrix differences of the chemicals listed for testing, no one...

  8. Development and Challenge of HIV/AIDS Testing Laboratory Network and Quality Assurance System in China

    Institute of Scientific and Technical Information of China (English)


    This paper describes the development and challenge of HIV/AIDS testing laboratory network and quality assurance system in China. At present, the HIV/AIDS testing laboratories includes three classes, the National AIDS Reference Laboratory, HIV/AIDS confirmatory laboratories and HIV/AIDS screening laboratories. All of them are accredited by the health authorities, and each class of laboratories take charge of their function strictly according to the "National Management of HIV/AIDS Detection (2006)". A complete quality assurance and quality control system for HIV/AIDS testing has been developed, which includes technical training, strict laboratory monitoring and approval,examination or proficiency testing on HIV/AIDS detection, and quality evaluation and supervision of HIV/AIDS diagnostic kits. Besides conduct the routine anti-HIV antibody test, more and more laboratories began to conduct other tests, such as CD4+ T lymphocyte cell counting, HIV viral load, HIV DNA PCR, genotyping, drug resistance, and HIV-1 recent infection test. The primary challenges faced by the HIV/AIDS testing laboratory network are in the areas of laboratory management and quality control. For example, the provincial PT program is inefficient, the internal quality control is conducted perfunctorily, personnel training can not met the needs of the workplace, which need to be improved.

  9. Comparison of serological tests for antibody to hepatitis A antigen, using coded specimens from individuals infected with the MS-1 strain of hepatitis A virus. (United States)

    Dienstag, J L; Krugman, S; Wong, D C; Purcell, R H


    To compare serological tests for antibody to hepatitis A antigen (anti-HA), we tested 15 paired serum specimens, submitted under code, from individuals infected with the MS-1 strain of hepatitis A virus. Immune electron microscopy (IEM), immune adherence hemagglutination (IAHA), and solid-phase radioimmunoassay (RIA) tests for anti-HA were performed with hepatitis A antigen (HA Ag) derived from human stool; results were also compared with previously reported titers determined by IAHA with HA Ag derived from marmoset liver. Antibody titers (IAHA and RIA) and ratings (IEM) determined with stool-derived HA Ag compared favorably, and a seroresponse to HA Ag was detected by all three methods for every serum pair tested. Differences in titers were noted between IAHA tests with liver-derived and with stool-derived HA Ag, but the discrepancies could be accounted for by differences in test technique. The agreement found in this study among the three techniques was quite good and confirms the specificity and sensitivity of tests for anti-HA that are done with stool-derived HA-Ag. PMID:186409

  10. EXCEDE Technology Development III: First Vacuum Tests

    CERN Document Server

    Belikov, Ruslan; Pluzhnik, Eugene; Hix, Troy T; Bendek, Eduardo; Thomas, Sandrine J; Lynch, Dana H; Mihara, Roger; Irwin, J Wes; Duncan, Alan L; Greene, Thomas P; Guyon, Olivier; Kendrick, Richard L; Smith, Eric H; Witteborn, Fred C; Schneider, Glenn


    This paper is the third in the series on the technology development for the EXCEDE (EXoplanetary Circumstellar Environments and Disk Explorer) mission concept, which in 2011 was selected by NASA's Explorer program for technology development (Category III). EXCEDE is a 0.7m space telescope concept designed to achieve raw contrasts of 1e6 at an inner working angle of 1.2 l/D and 1e7 at 2 l/D and beyond. This will allow it to directly detect and spatially resolve low surface brightness circumstellar debris disks as well as image giant planets as close as in the habitable zones of their host stars. In addition to doing fundamental science on debris disks, EXCEDE will also serve as a technological and scientific precursor for any future exo-Earth imaging mission. EXCEDE uses a Starlight Suppression System (SSS) based on the PIAA coronagraph, enabling aggressive performance. We report on our continuing progress of developing the SSS for EXCEDE, and in particular (a) the reconfiguration of our system into a more fli...

  11. Asteroid Regolith Simulants: Development, Characteristics, and Testing (United States)

    Britt, D. T.


    As part of a NASA Small Business Innovation Research (SBIR) award to the University of Central Florida and Deep Space Industries, we are developing a family of asteroid regolith simulants based on meteorite mineralogies but using terrestrial materials, to support NASAs exploration goals for asteroids. We are planning on developing five types of simulant based on the following meteorite types: CI-carbonaceous chondrite, CM-carbonaceous chondrite, Tagish Lake, L-ordinary chondrite, and iron. To the greatest extent reasonable (based on input costs and health/safety) we will duplicate the mineralogy, chemistry, oxidation state, hydration state, and particle size distribution found in regolith meteorites of each type. The major limitations on the fidelity of simulant will be health and safety issues for the users of the simulants. For example, much of the organic component of volatile-rich carbonaceous chondrites are in the form of Polycyclic Aromatic Hydrocarbons (PAHs). These are essentially combustion residues, possibly of complex regolith processing, with more carbon atoms than hydrogen. However, many PAHs are toxic, carcinogenic, and/or mutagenic. Several are banned in the European Union and California. This sort of material would endanger users, be impossible to distribute, and not make a useable regolith simulant. There are several reasonable, no-toxic alternatives to PAHs. We will report on the status of simulant development and the progress of our validation experiments.

  12. Transcription and the IELTS Speaking Test: Facilitating Development (United States)

    Stones, Thomas P.


    This article describes a transcription task cycle that was designed to facilitate the development of skills for the IELTS (International English Language Testing System) speaking test at a language school in Japan. The cycle involved practice test, transcription, student correction, teacher correction, and retrial of the original test and…

  13. Development and application of pathovar-specific monoclonal antibodies that recognize the lipopolysaccharide O antigen and the type IV fimbriae of Xanthomonas hyacinthi

    Energy Technology Data Exchange (ETDEWEB)

    Doorn, J. van; Ojanen-Reuhs, T.; Hollinger, T.C.; Reuhs, B.L.; Schots, A.; Boonekamp, P.M.; Oudega, B.


    The objective of this study was to develop a specific immunological diagnostic assay for yellow disease in hyacinths, using monoclonal antibodies (MAbs). Mice were immunized with a crude cell wall preparation (shear fraction) from Xanthomonas hyacinthi and with purified type IV fimbriae. Hybridomas were screened for a positive reaction with X. hyacinthi cells or fimbriae and for a negative reaction with X. translucens pv. graminis or Erwinia carotovora subsp. carotovora. Nine MAbs recognized fimbrial epitopes, as shown by immunoblotting, immunofluorescence, enzyme-linked immunosorbent assay (ELISA), and immunoelectron microscopy; however, three of these MAbs had weak cross-reactions with two X. translucens pathovars in immunoblotting experiments. Seven MAbs reacted with lipopolysaccharides and yielded a low-mobility ladder pattern on immunoblots. Subsequent analysis of MAb 2E5 showed that it specifically recognized an epitope on the O antigen, which was found to consist of rhamnose and fucose in a 2:1 molar ratio. The cross-reaction of MAb 2E5 with all X. hyacinthi strains tested showed that this O antigen is highly conserved within this species. MAb 1B10 also reacted with lipopolysaccharides. MAbs 2E5 and 1B10 were further tested in ELISA and immunoblotting experiments with cells and extracts from other pathogens. No cross-reaction was found with 27 other Xanthomonas pathovars tested or with 14 other bacterial species from other genera, such as Erwinia and Pseudomonas, indicating the high specificity of these antibodies. MAbs 2E5 and 1B10 were shown to be useful in ELISA for the detection of X. hyacinthi in infected hyacinths.

  14. Hybridization-based antibody cDNA recovery for the production of recombinant antibodies identified by repertoire sequencing. (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


    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.

  15. Euclid mirrors and test collimator: AMOS developments (United States)

    Gloesener, Pierre; Wolfs, Fabrice; Cola, Marcel; Pirnay, Olivier; Flebus, Carlo


    EUCLID is an optical/near-infrared survey mission to be launched in 2020 towards the L2 Lagrange point. It will aim at studying the dark universe and providing a better understanding of the origin of the accelerating expansion of the universe. Through the use of cosmological sounding, it will investigate the nature of dark energy, dark matter and gravity by tracking their observational signatures on the geometry of the universe and on the cosmic history of large structures formation. The EUCLID payload module (PLM) consists of a 1.2 m-class telescope and will accommodate two instruments. As a subcontractor of AIRBUS Defence and Space, AMOS is responsible for the manufacturing of the secondary and the third mirrors of the telescope as well as for the flat folding mirror set within the focal plane arrangement of EUCLID telescope, which incorporates dedicated filtering functions. AMOS produces in addition the 1.3 m-class test collimator for the on-ground validation of the EUCLID instrument.

  16. Immunoprophylaxis in fish by injection of mouse antibody genes

    DEFF Research Database (Denmark)

    Lorenzen, Niels; Cupit, P.M.; Einer-Jensen, Katja;


    Antibodies are a crucial part of the body's specific defense against infectious diseases and have considerable potential as therapeutic and prophylactic agents in humans and animals, The development of recombinant single-chain antibodies allows a genetic application strategy for prevention...... of infectious diseases. To test this in a fish model, a gene construct encoding a neutralizing single-chain antibody to the fish-pathogenic rhabdovirus VHSV (viral hemorrhagic septicemia virus) was administered to rainbow trout by intramuscular injection of plasmid DNA, Circulating recombinant antibodies could...

  17. Development of a stable low-dose aglycosylated antibody formulation to minimize protein loss during intravenous administration (United States)

    Morar-Mitrica, Sorina; Puri, Manasi; Beumer Sassi, Alexandra; Fuller, Joshua; Hu, Ping; Crotts, George; Nesta, Douglas


    The physical and chemical integrity of a biopharmaceutical must be maintained not only during long-term storage but also during administration. Specifically for the intravenous (i.v.) delivery of a protein drug, loss of stability can occur when the protein formulation is compounded with i.v. bag diluents, thus modifying the original composition of the drug product. Here we present the challenges associated with the delivery of a low-dose, highly potent monoclonal antibody (mAb) via the i.v. route. Through parallel in-use stability studies and conventional formulation development, a drug product was developed in which adsorptive losses and critical oxidative degradation pathways were effectively controlled. This development approach enabled the i.v. administration of clinical doses in the range of 0.1 to 0.5 mg total protein, while ensuring liquid drug product storage stability under refrigerated conditions. PMID:26073995

  18. Antimicrobial Testing Methods & Procedures Developed by EPA's Microbiology Laboratory (United States)

    We develop antimicrobial testing methods and standard operating procedures to measure the effectiveness of hard surface disinfectants against a variety of microorganisms. Find methods and procedures for antimicrobial testing.

  19. Monoclonal antibodies to desmin: evidence for stage-dependent intermediate filament immunoreactivity during cardiac and skeletal muscle development. (United States)

    Fischman, D A; Danto, S I


    Monoclonal antibodies reactive with desmin (D3 and D76) have been generated and their specificities validated by immunoblots, RIAs, and immunocytochemistry. No cross-reaction with other IFPs has been observed. The McAbs recognized different epitopes but both reside in the amino-terminal rod domain of desmin. Whereas McAb D3 produces a staining pattern characteristic of desmin throughout the development of cardiac and skeletal muscles, McAb D76 was selectively unreactive with certain regions of early (three days in ovo) embryonic cardiac anlage, with cultured cardiac myocytes derived from 7-day-old embryos, and with skeletal myotubes in early stages of myogenesis in vitro. Positive reactivity of D76 was seen at stages of myofibrillogenesis when the sarcomeres assume lateral alignment. Evidence was presented that differential reactivity of D76 did not result from the biosynthesis of a new desmin isoform or the post-translational modification of an existing protein. We suggest that the appearance of D76 immunoreactivity during striated muscle development represents an unmasking of the epitope by some IF-associated protein. Since this transition during skeletal muscle differentiation occurs during lateral alignment of the myofibrils, this antibody may serve as a useful probe for exploring this reorganization of the contractile apparatus during myogenesis and muscle regeneration.

  20. Clinical Utility of Random Anti–Tumor Necrosis Factor Drug–Level Testing and Measurement of Antidrug Antibodies on the Long‐Term Treatment Response in Rheumatoid Arthritis (United States)

    Jani, Meghna; Chinoy, Hector; Warren, Richard B.; Griffiths, Christopher E. M.; Plant, Darren; Fu, Bo; Morgan, Ann W.; Wilson, Anthony G.; Isaacs, John D.; Hyrich, KimmeL.; Prouse, P. J.; Moitra, R. K.; Shawe, D. J.; Nisar, M.; Fairburn, K.; Nixon, J.; Barnes, T.; Hui, M.; Coady, D.; Wright, D.; Morley, C.; Raftery, G.; Bracewell, C.; Bridges, M.; Armstrong, D.; Chuck, A. J.; Hailwood, S.; Kumar, N.; Ashok, D.; Reece, R.; O'Reilly, S. C.; Ding, T.; Badcock, L. J.; Deighton, C. M.; Raj, N.; Regan, M. R.; Summers, G. D.; Williams, R. A.; Lambert, J. R.; Stevens, R.; Wilkinson, C.; Kelly, C. A.; Hamilton, J.; Heycock, C. R.; Saravanan, V.; Cope, A.; Garrood, T.; Ng, N.; Kirkham, B.; Green, M.; Gough, A.; Lawson, C.; Das, D.; Borbas, E.; Wazir, T.; Emery, P.; Bingham, S.; Bird, H. A.; Conaghan, P.G.; Pease, C. T.; Wakefield, R. J.; Buch, M.; Bruce, I.; Gorodkin, R.; Ho, P.; Parker, B.; Smith, W.; Jenkins, E.; Mukhtyar, C.; Gaffney, K.; Macgregor, A. J.; Marshall, T.; Merry, P.; DeSilva, C.; Birrell, F. N.; Crook, P. R.; Szebenyi, B.; Bates, D.; James, D.; Gillott, T.; Alvi, A.; Grey, C.; Browning, J.; McHale, J. F.; Gaywood, I.C.; Jones, A. C.; Lanyon, P.; Pande, I.; Doherty, M.; Gupta, A.; Courtney, P. A.; Srikanth, A.; Abhishek, A.; Das, L.; Pattrick, M.; Snowden, H. N.; Bowden, A. P.; Smith, E. E.; Klimiuk, P.; Speden, D. J.; Naz, S.; Ledingham, J. M.; Hull, R. G.; McCrae, F.; Cooper, A.; Young‐Min, S. A.; Wong, E.; Shaban, R.; Woolf, A. D.; Davis, M.; Hutchinson, D.; Endean, A.; Mewar, D.; Tunn, E. J.; Nelson, K.; Kennedy, T. D.; Dubois, C.; Pauling, J.; Korendowych, E.; Jenkinson, T.; Sengupta, R.; Bhalla, A.; McHugh, N.; O'Neil, T.; Herrick, A. L.; Jones, A. K.; Cooper, R. G.; Dixon, W. G.; Harrison, B.; Buckley, C. D.; Carruthers, D. C.; Elamanchi, R.; Gordon, P. C.; Grindulis, K. A.; Khattak, F.; Raza, K.; Situnayake, K.; Akil, M.; Till, S.; Dunkley, L.; Tattersall, R.; Kilding, R.; Tait, T.; Maxwell, J.; Till, S.; Kuet, K.-P.; Plant, M. J.; Clarke, F.; Fordham, J. N.; Tuck, S.; Pathare, S. K.; Paul, A.; Marguerie, C. P.; Rigby, S. P.; Dunn, N.; Abbas, I.; Filer, C.; Abernethy, V. E.; Clewes, A. R.; Dawson, J. K.; Kitas, G.; Erb, N.; Klocke, R.; Whallett, A. J.; Douglas, K.; Pace, A.; Sandhu, R.; John, H.; Shand, L.; Lane, S.; Foster, H.; Griffiths, B.; Griffiths, I.; Kay, L.; Ng, W.-F.; Platt, P. N.; Walker, D. J.; Peterson, P.; Lorenzi, A.; Friswell, M.; Thompson, B.; Lee, M.; Pratt, A.; Hopkinson, N. D.; Dunne, C. A.; Quilty, B.; Marks, J.; Mukherjee, S.; Mulherin, D.; Chalam, S. V.; Price, T.; Sheeran, T.; Venkatachalam, S.; Baskar, S.; Al- Allaf, W.; McKenna, F.; Shah, P.; Filer, A.; Bowman, S. J.; Jobanputra, P.; Rankin, E. C.; Allen, M.; Chaudhuri, K.; Dubey, S.; Price‐Forbes, A.; Ravindran, J.; Samanta, A.; Sheldon, P.; Hassan, W.; Francis, J.; Kinder, A.; Neame, R.; Moorthy, A.; Bukhari, M.; Ottewell, L.; Palkonyai, E.; Hider, S.; Hassell, A.; Menon, A.; Dowson, C.; Kamath, S.; Packham, J.; Dutta, S.; Price, S.; Roddy, E.; Paskins, Z.; O'Reilly, D. T.; Rajagopal, V.; Bhagat, S.; Chattopadhyay, C. B.; Green, M.; Quinn, D.; Isdale, A.; Brown, A.; Saleem, B.; Foo, B.; Al Saffar, Z.; Koduri, G.


    . A body mass index of ≥30 kg/m2 and poor adherence were associated with lower drug levels. Conclusion Pharmacologic testing in anti–tumor necrosis factor–treated patients is clinically useful even in the absence of trough levels. At 3 months, antidrug antibodies and low adalimumab levels are significant predictors of no response according to the EULAR criteria at 12 months. PMID:26109489

  1. Characterization of Guinea Pig Antibody Responses to Salivary Proteins of Triatoma infestans for the Development of a Triatomine Exposure Marker (United States)

    Dorňáková, Veronika; Salazar-Sanchez, Renzo; Borrini-Mayori, Katty; Carrion-Navarro, Oscar; Levy, Michael Z.; Schaub, Günter A.; Schwarz, Alexandra


    Background Salivary proteins of Triatoma infestans elicit humoral immune responses in their vertebrate hosts. These immune responses indicate exposure to triatomines and thus can be a useful epidemiological tool to estimate triatomine infestation. In the present study, we analyzed antibody responses of guinea pigs to salivary antigens of different developmental stages of four T. infestans strains originating from domestic and/or peridomestic habitats in Argentina, Bolivia, Chile and Peru. We aimed to identify developmental stage- and strain-specific salivary antigens as potential markers of T. infestans exposure. Methodology and Principal Findings In SDS-PAGE analysis of salivary proteins of T. infestans the banding pattern differed between developmental stages and strains of triatomines. Phenograms constructed from the salivary profiles separated nymphal instars, especially the 5th instar, from adults. To analyze the influence of stage- and strain-specific differences in T. infestans saliva on the antibody response of guinea pigs, twenty-one guinea pigs were exposed to 5th instar nymphs and/or adults of different T. infestans strains. Western blot analyses using sera of exposed guinea pigs revealed stage- and strain-specific variations in the humoral response of animals. In total, 27 and 17 different salivary proteins reacted with guinea pig sera using IgG and IgM antibodies, respectively. Despite all variations of recognized salivary antigens, an antigen of 35 kDa reacted with sera of almost all challenged guinea pigs. Conclusion Salivary antigens are increasingly considered as an epidemiological tool to measure exposure to hematophagous arthropods, but developmental stage- and strain-specific variations in the saliva composition and the respective differences of immunogenicity are often neglected. Thus, the development of a triatomine exposure marker for surveillance studies after triatomine control campaigns requires detailed investigations. Our study resulted

  2. Characterization of guinea pig antibody responses to salivary proteins of Triatoma infestans for the development of a triatomine exposure marker.

    Directory of Open Access Journals (Sweden)

    Veronika Dorňáková


    Full Text Available BACKGROUND: Salivary proteins of Triatoma infestans elicit humoral immune responses in their vertebrate hosts. These immune responses indicate exposure to triatomines and thus can be a useful epidemiological tool to estimate triatomine infestation. In the present study, we analyzed antibody responses of guinea pigs to salivary antigens of different developmental stages of four T. infestans strains originating from domestic and/or peridomestic habitats in Argentina, Bolivia, Chile and Peru. We aimed to identify developmental stage- and strain-specific salivary antigens as potential markers of T. infestans exposure. METHODOLOGY AND PRINCIPAL FINDINGS: In SDS-PAGE analysis of salivary proteins of T. infestans the banding pattern differed between developmental stages and strains of triatomines. Phenograms constructed from the salivary profiles separated nymphal instars, especially the 5th instar, from adults. To analyze the influence of stage- and strain-specific differences in T. infestans saliva on the antibody response of guinea pigs, twenty-one guinea pigs were exposed to 5th instar nymphs and/or adults of different T. infestans strains. Western blot analyses using sera of exposed guinea pigs revealed stage- and strain-specific variations in the humoral response of animals. In total, 27 and 17 different salivary proteins reacted with guinea pig sera using IgG and IgM antibodies, respectively. Despite all variations of recognized salivary antigens, an antigen of 35 kDa reacted with sera of almost all challenged guinea pigs. CONCLUSION: Salivary antigens are increasingly considered as an epidemiological tool to measure exposure to hematophagous arthropods, but developmental stage- and strain-specific variations in the saliva composition and the respective differences of immunogenicity are often neglected. Thus, the development of a triatomine exposure marker for surveillance studies after triatomine control campaigns requires detailed

  3. Developing a TTCN-3 Test Harness for Legacy Software

    DEFF Research Database (Denmark)

    Okika, Joseph C.; Ravn, Anders Peter; Siddalingaiah, Lokesh;


    control software in C, a Graphical User Interface (GUI) and the connectors in Java. Our experience shows that it is feasible to use TTCN-3 in developing a test harness for a legacy software for an embedded system, even when it involves different heterogeneous components....... challenge in developing the test harness is to interface a generic test driver to the legacy software and provide a suitable interface for test engineers. The main contribution of this paper is a demonstration of a suitable design for such a test harness. It includes: a TTCN-3 test driver in C++, the legacy...

  4. Engineering model development and test results (United States)

    Wellman, John A.


    The correctability of the primary mirror spherical error in the Wide Field/Planetary Camera (WF/PC) is sensitive to the precise alignment of the incoming aberrated beam onto the corrective elements. Articulating fold mirrors that provide +/- 1 milliradian of tilt in 2 axes are required to allow for alignment corrections in orbit as part of the fix for the Hubble space telescope. An engineering study was made by Itek Optical Systems and the Jet Propulsion Laboratory (JPL) to investigate replacement of fixed fold mirrors within the existing WF/PC optical bench with articulating mirrors. The study contract developed the base line requirements, established the suitability of lead magnesium niobate (PMN) actuators and evaluated several tilt mechanism concepts. Two engineering model articulating mirrors were produced to demonstrate the function of the tilt mechanism to provide +/- 1 milliradian of tilt, packaging within the space constraints and manufacturing techniques including the machining of the invar tilt mechanism and lightweight glass mirrors. The success of the engineering models led to the follow on design and fabrication of 3 flight mirrors that have been incorporated into the WF/PC to be placed into the Hubble Space Telescope as part of the servicing mission scheduled for late 1993.

  5. Serum herpes simplex antibodies (United States)

    ... 2. HSV-1 most often causes cold sores (oral herpes). HSV-2 causes genital herpes. How the Test ... whether a person has ever been infected with oral or genital herpes . It looks for antibodies to herpes simplex virus ...

  6. 抗磷脂抗体检测的现状及展望%Current status and prospects of antiphospholipid antibodies tests

    Institute of Scientific and Technical Information of China (English)

    张蜀澜; 李永哲


    抗磷脂抗体(APLs)是辅助诊断抗磷脂综合征(APS)的重要实验室指标,是血栓形成和合并妊娠时的主要危险因素之一.但是由于APLs存在显著异质性,检测方法标准化程度较低,不同实验室间检测结果一致性较差,一定程度上限制了APLs检测的临床应用和对于APS诊治结果的进一步认识.因此,亟须建立APLs检测的标准化体系,提高检测方法的特异性、敏感性和重复性,实施设计合理的APLs检测结果大规模的临床评估.%Antiphospholipid antibodies (APLs) are important for the diagnosis of antiphospholipid syndrome (APS),especially for predicting the risk of thrombosis and pathological pregnancy.However,the heterogeneity of antiphospholipid antibodies,lacking of standardization and significant interlaboratory variation binder the clinical application of APLs and better understanding of APS diagnosis and treatment.Therefore,it is urgent to establish a standardize system for antiphospholipid antibodies test and to improve the performance of the test and perform well-designed clinical evaluation.

  7. Powertrain instrumentation and test systems development, hybridization, electrification

    CERN Document Server

    Paulweber, Michael


    The book deals with the increasingly complex test systems for powertrain components and systems giving an overview of the diverse types of test beds for all components of an advanced powertrain focusing on specific topics such as instrumentation, control, simulation, hardware-in-the-loop, automation or test facility management. This book is intended for powertrain (component) development engineers, test bed planners, test bed operators and beginners.

  8. Serologic test development. Progress report, July 1, 1974--June 30, 1975. [Radioimmunoassay method for diagnosis of swine and bovine diseases

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, G.C.; Clinard, E.H.; Sanders, W.M.; Bartlett, M.L.; Payne, R.J.


    The Enzyme-Labeled Antibody (ELA) test system has been adapted to microtiter trays for both cell bound and soluble antigens. Problems involving both readout instrumentation and reaction product stability have been solved. Progress involving application of the ELA system for detection of hog cholera, trichinosis, swine brucellosis, and swine and bovine tuberculosis is reported. Prototype instrumentation for automating ELA processing is being developed. (auth)

  9. A pilot study comparing the development of EIAV Env-specific antibodies induced by DNA/recombinant vaccinia-vectored vaccines and an attenuated Chinese EIAV vaccine. (United States)

    Meng, Qinglai; Lin, Yuezhi; Ma, Jian; Ma, Yan; Zhao, Liping; Li, Shenwei; Yang, Kai; Zhou, Jianhua; Shen, Rongxian; Zhang, Xiaoyan; Shao, Yiming


    Data from successful attenuated lentiviral vaccine studies indicate that fully mature Env-specific antibodies characterized by high titer, high avidity, and the predominant recognition of conformational epitopes are associated with protective efficacy. Although vaccination with a DNA prime/recombinant vaccinia-vectored vaccine boost strategy has been found to be effective in some trials with non-human primate/simian/human immunodeficiency virus (SHIV) models, it remains unclear whether this vaccination strategy could elicit mature equine infectious anemia virus (EIAV) Env-specific antibodies, thus protecting vaccinated horses against EIAV infection. Therefore, in this pilot study we vaccinated horses using a strategy based on DNA prime/recombinant Tiantan vaccinia (rTTV)-vectored vaccines encoding EIAV env and gag genes, and observed the development of Env-specific antibodies, neutralizing antibodies, and p26-specific antibodies. Vaccination with DNA induced low titer, low avidity, and the predominant recognition of linear epitopes by Env-specific antibodies, which was enhanced by boosting vaccinations with rTTV vaccines. However, the maturation levels of Env-specific antibodies induced by the DNA/rTTV vaccines were significantly lower than those induced by the attenuated vaccine EIAV(FDDV). Additionally, DNA/rTTV vaccines did not elicit broadly neutralizing antibodies. After challenge with a virulent EIAV strain, all of the vaccinees and control horses died from EIAV disease. These data indicate that the regimen of DNA prime/rTTV vaccine boost did not induce mature Env-specific antibodies, which might have contributed to immune protection failure.

  10. Development and validation of a theoretical test in basic laparoscopy

    DEFF Research Database (Denmark)

    Strandbygaard, Jeanett; Maagaard, Mathilde; Larsen, Christian Rifbjerg;


    for first-year residents in obstetrics and gynecology. This study therefore aimed to develop and validate a framework for a theoretical knowledge test, a multiple-choice test, in basic theory related to laparoscopy. METHODS: The content of the multiple-choice test was determined by conducting informal...... levels: senior medical students, first-year residents, and chief physicians. RESULTS: The four conversational interviews resulted in the development of 47 test questions, which were narrowed down to 37 test questions after two Delphi rounds involving 12 chief physicians. Significant differences were.......001). Internal consistency (Cronbach's alpha) was 0.82. There was no evidence of differential item functioning between the three groups tested. CONCLUSIONS: A newly developed knowledge test in basic laparoscopy proved to have content and construct validity. The formula for the development and validation...

  11. [Anti-alpha-gliadin antibodies. Sensitivity, specificity and correlation with blood xylose test in the 3 diagnostic stages of celiac disease in children]. (United States)

    Ventura, A; Florean, P; Trevisan, M; Not, T; Perticarari, S; Quadrifoglio, F; Torre, G; Cauci, S


    The specificity and sensibility of IgA and IgG alfagliadin antibody test (AaGA) for screening, diagnosis and follow-up of childhood coeliac disease has been evaluated. We have compared AaGA test to D-xylose blood test and at last we have examined the false positive and negative results given by the test. Two groups of subjects were considered: 1) 90 children with untreated coeliac disease (21 newly diagnosed (I stage), 50 in gluten withdrawal (II stage), 19 in challenge (III stage); 2) 255 disease controls including: 157 healthy controls; 31 children with gastroenterological disorders other than coeliac disease; 31 children with food allergy and atopic dermatitis; 36 children with "constitutional" short stature (without GH deficiency and with normal intestinal mucosa). The sensibility of AaGA test in the first stage of coeliac disease has been of 95.2% for the IgG class antibody and 90.4% for the IgA class; on the other hand the showed a specificity of 83.6% for IgG class antibody and 96.9% for IgA class. In only two newly diagnosed coeliac children we have found false negative results: in the first case the patient was IgA-deficient, in the second the age was above 3 years. AaGA IgA resulted positive only in the 12.9% of the group of gastroenterological and atopic controls; particularly most cases were affected by multiple food allergies and two patients by chronic autoimmune disease of small intestine.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Initial development and preliminary evaluation of a multiplex bead assay to detect antibodies to Ehrlichia canis, Anaplasma platys, and Ehrlichia chaffeensis outer membrane peptides in naturally infected dogs from Grenada, West Indies. (United States)

    Wilkerson, Melinda J; Black, Kelley E; Lanza-Perea, Marta; Sharma, Bhumika; Gibson, Kathryn; Stone, Diana M; George, Anushka; Nair, Arathy D S; Ganta, Roman R


    Tick-borne bacteria, Ehrlichia canis, Anaplasma platys, and Ehrlichia chaffeensis are significant pathogens of dogs worldwide, and coinfections of E. canis and A. platys are common in dogs on the Caribbean islands. We developed and evaluated the performance of a multiplex bead-based assay to detect antibodies to E. canis, A. platys, and E. chaffeensis peptides in dogs from Grenada, West Indies, where E. canis and A. platys infections are endemic. Peptides from outer membrane proteins of P30 of E. canis, OMP-1X of A. platys, and P28-19/P28-14 of E. chaffeensis were coupled to magnetic beads. The multiplex peptide assay detected antibodies in dogs experimentally infected with E. canis and E. chaffeensis, but not in an A. platys experimentally infected dog. In contrast, the multiplex assay and an in-house enzyme-linked immunosorbent assay (ELISA) detected A. platys antibodies in naturally infected Grenadian dogs. Following testing of 104 Grenadian canine samples, multiplex assay results had good agreement with commercially available ELISA and immunofluorescent assay for E. canis antibody-positive dogs ( K values of 0.73 and 0.84), whereas A. platys multiplex results had poor agreement with these commercial assays ( K values of -0.02 and 0.01). Prevalence of seropositive E. canis and A. platys Grenadian dogs detected by the multiplex and commercial antibody assays were similar to previous reports. Although the multiplex peptide assay performed well in detecting the seropositive status of dogs to E. canis and had good agreement with commercial assays, better antigen targets are necessary for the antibody detection of A. platys.

  13. Development and application of an antibody-based protein microarray to assess physiological stress in grizzly bears (Ursus arctos). (United States)

    Carlson, Ruth I; Cattet, Marc R L; Sarauer, Bryan L; Nielsen, Scott E; Boulanger, John; Stenhouse, Gordon B; Janz, David M


    A novel antibody-based protein microarray was developed that simultaneously determines expression of 31 stress-associated proteins in skin samples collected from free-ranging grizzly bears (Ursus arctos) in Alberta, Canada. The microarray determines proteins belonging to four broad functional categories associated with stress physiology: hypothalamic-pituitary-adrenal axis proteins, apoptosis/cell cycle proteins, cellular stress/proteotoxicity proteins and oxidative stress/inflammation proteins. Small skin samples (50-100 mg) were collected from captured bears using biopsy punches. Proteins were isolated and labelled with fluorescent dyes, with labelled protein homogenates loaded onto microarrays to hybridize with antibodies. Relative protein expression was determined by comparison with a pooled standard skin sample. The assay was sensitive, requiring 80 µg of protein per sample to be run in triplicate on the microarray. Intra-array and inter-array coefficients of variation for individual proteins were generally bears. This suggests that remotely delivered biopsy darts could be used in future sampling. Using generalized linear mixed models, certain proteins within each functional category demonstrated altered expression with respect to differences in year, season, geographical sampling location within Alberta and bear biological parameters, suggesting that these general variables may influence expression of specific proteins in the microarray. Our goal is to apply the protein microarray as a conservation physiology tool that can detect, evaluate and monitor physiological stress in grizzly bears and other species at risk over time in response to environmental change.

  14. Generation of recombinant porcine parvovirus virus-like particles in Saccharomyces cerevisiae and development of virus-specific monoclonal antibodies. (United States)

    Tamošiūnas, Paulius Lukas; Petraitytė-Burneikienė, Rasa; Lasickienė, Rita; Akatov, Artiomas; Kundrotas, Gabrielis; Sereika, Vilimas; Lelešius, Raimundas; Žvirblienė, Aurelija; Sasnauskas, Kęstutis


    Porcine parvovirus (PPV) is a widespread infectious virus that causes serious reproductive diseases of swine and death of piglets. The gene coding for the major capsid protein VP2 of PPV was amplified using viral nucleic acid extract from swine serum and inserted into yeast Saccharomyces cerevisiae expression plasmid. Recombinant PPV VP2 protein was efficiently expressed in yeast and purified using density gradient centrifugation. Electron microscopy analysis of purified PPV VP2 protein revealed the self-assembly of virus-like particles (VLPs). Nine monoclonal antibodies (MAbs) against the recombinant PPV VP2 protein were generated. The specificity of the newly generated MAbs was proven by immunofluorescence analysis of PPV-infected cells. Indirect IgG ELISA based on the recombinant VLPs for detection of PPV-specific antibodies in swine sera was developed and evaluated. The sensitivity and specificity of the new assay were found to be 93.4% and 97.4%, respectively. In conclusion, yeast S. cerevisiae represents a promising expression system for generating recombinant PPV VP2 protein VLPs of diagnostic relevance.

  15. Generation of Recombinant Schmallenberg Virus Nucleocapsid Protein in Yeast and Development of Virus-Specific Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Justas Lazutka


    Full Text Available Schmallenberg virus (SBV, discovered in continental Europe in late 2011, causes mild clinical signs in adult ruminants, including diarrhoea and reduced milk yield. However, fetal infection can lead to severe malformation in newborn offspring. To develop improved reagents for SBV serology, a high-level yeast expression system was employed to produce recombinant SBV nucleocapsid (N protein. Recombinant SBV N protein was investigated as an antigen in SBV-specific IgG enzyme immunoassay and used for generation of monoclonal antibodies (MAbs. Yeast-expressed SBV N protein was reactive with anti-SBV IgG-positive cow serum specimens collected from different farms of Lithuania. After immunization of mice with recombinant SBV N protein, four MAbs were generated. The MAbs raised against recombinant SBV N protein reacted with native viral nucleocapsids in SBV-infected BHK cells by immunofluorescence assay. The reactivity of recombinant N protein with SBV-positive cow serum specimens and the ability of the MAbs to recognize virus-infected cells confirm the antigenic similarity between yeast-expressed SBV N protein and native viral nucleocapsids. Our study demonstrates that yeast expression system is suitable for high-level production of recombinant SBV N protein and provides the first evidence on the presence of SBV-specific antibodies in cow serum specimens collected in Lithuania.

  16. The role of evolutionarily conserved germ-line DH sequence in B-1 cell development and natural antibody production. (United States)

    Vale, Andre M; Nobrega, Alberto; Schroeder, Harry W


    Because of N addition and variation in the site of VDJ joining, the third complementarity-determining region of the heavy chain (CDR-H3) is the most diverse component of the initial immunoglobulin antigen-binding site repertoire. A large component of the peritoneal cavity B-1 cell component is the product of fetal and perinatal B cell production. The CDR-H3 repertoire is thus depleted of N addition, which increases dependency on germ-line sequence. Cross-species comparisons have shown that DH gene sequence demonstrates conservation of amino acid preferences by reading frame. Preference for reading frame 1, which is enriched for tyrosine and glycine, is created both by rearrangement patterns and by pre-BCR and BCR selection. In previous studies, we have assessed the role of conserved DH sequence by examining peritoneal cavity B-1 cell numbers and antibody production in BALB/c mice with altered DH loci. Here, we review our finding that changes in the constraints normally imposed by germ-line-encoded amino acids within the CDR-H3 repertoire profoundly affect B-1 cell development, especially B-1a cells, and thus natural antibody immunity. Our studies suggest that both natural and somatic selection operate to create a restricted B-1 cell CDR-H3 repertoire.

  17. Generation of Recombinant Porcine Parvovirus Virus-Like Particles in Saccharomyces cerevisiae and Development of Virus-Specific Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Paulius Lukas Tamošiūnas


    Full Text Available Porcine parvovirus (PPV is a widespread infectious virus that causes serious reproductive diseases of swine and death of piglets. The gene coding for the major capsid protein VP2 of PPV was amplified using viral nucleic acid extract from swine serum and inserted into yeast Saccharomyces cerevisiae expression plasmid. Recombinant PPV VP2 protein was efficiently expressed in yeast and purified using density gradient centrifugation. Electron microscopy analysis of purified PPV VP2 protein revealed the self-assembly of virus-like particles (VLPs. Nine monoclonal antibodies (MAbs against the recombinant PPV VP2 protein were generated. The specificity of the newly generated MAbs was proven by immunofluorescence analysis of PPV-infected cells. Indirect IgG ELISA based on the recombinant VLPs for detection of PPV-specific antibodies in swine sera was developed and evaluated. The sensitivity and specificity of the new assay were found to be 93.4% and 97.4%, respectively. In conclusion, yeast S. cerevisiae represents a promising expression system for generating recombinant PPV VP2 protein VLPs of diagnostic relevance.

  18. Development and characterization of neutralizing monoclonal antibodies against canine distemper virus hemagglutinin protein. (United States)

    Bi, Zhenwei; Xia, Xingxia; Wang, Yongshan; Mei, Yongjie


    Canine distemper virus (CDV) causes a serious multisystemic disease in dogs and other carnivora. Hemagglutinin (H) protein-specific antibodies are mainly responsible for protective immunity against CDV infection. In the present study, six neutralizing MAbs to the H protein of CDV were newly obtained and characterized by immunizing BALB/c mice with a recent Chinese field isolate. Competitive binding inhibition assay revealed that they recognized four distinct antigenic regions of the H protein. Immunofluorescence assay and western blotting showed that all MAbs recognize the conformational rather than the linear epitopes of the H protein. Furthermore, in immunofluorescence and virus neutralization assays, two of the MAbs were found to react only with the recent Chinese field isolate and not with older CDV strains, including vaccine strain Onderstepoort, indicating there are neutralization-related antigenic variations between the recent Chinese field isolate and the older CDV strains examined in this study. The newly established MAbs are useful for differentiating the expanding CDV strains and could be used in immunotherapy and immunodiagnosis against infection with CDV.

  19. Development and application of a blocking enzyme-linked immunosorbent assay (ELISA) to differentiate antibodies against live and inactivated porcine reproductive and respiratory syndrome virus. (United States)

    Cong, Yanlong; Huang, Zhiqiang; Sun, Yixue; Ran, Wei; Zhu, Lisai; Yang, Guilian; Ding, Xuemei; Yang, Zhanqing; Huang, Xiao; Wang, Chunfeng; Ding, Zhuang


    The aim of this study was to establish a method that could differentiate antibodies against live and inactivated vaccines of porcine reproductive and respiratory syndrome virus (PRRSV). A blocking ELISA (b-ELISA) was established using the PRRSV non-structural protein, Nsp9, as the antigen and a monoclonal antibody, 2D6, against the Nsp9 protein as the capture antibody. The test was validated by using 415 clinical sera in the b-ELISA compared to a commercial kit based on the indirect ELISA using the nucleocapsid (N) protein as antigen. Significant differences were observed for the data obtained by the two detection methods. This may be due to the commercial kit detecting antibodies elicited by live and inactivated virus, whereas the b-ELISA only detects antibodies produced by any active viral replication, such as natural infection or live vaccination. Therefore, the b-ELISA in this study is able to distinguish between antibodies against live and inactivated viruses in pigs.

  20. Antibody Response to Plague Vaccination in Humans as Assayed by Staphylococcal Radioimmune Precipitation (St-RIP) Test (United States)


    Medical Microbiology and Immunology 163, 25-35. Cavanaugh, D. C., Elisberg, B. L., Llewellyn, C. H., Marshall, J. D., Jr., Rust, J. H.,I: Williams J. E...Schaeg, W. (1977). A radioimmunoassay for tetanus antibodies using protein A-containing Staphylococcus aureus. Medical Microbiology and Immunology 163...Putenherpesvirus. Medical Microbiology and Immunology 163, 14l-156. Kessler, S. W. (1975) Rapid isolation of antigens from tells with a staphylococa! protein

  1. Antibody informatics for drug discovery

    DEFF Research Database (Denmark)

    Shirai, Hiroki; Prades, Catherine; Vita, Randi;


    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...

  2. Interactive test tool for interoperable C-ITS development

    NARCIS (Netherlands)

    Voronov, A.; Englund, C.; Bengtsson, H.H.; Chen, L.; Ploeg, J.; Jongh, J.F.C.M. de; Sluis, H.J.D. van de


    This paper presents the architecture of an Interactive Test Tool (ITT) for interoperability testing of Cooperative Intelligent Transport Systems (C-ITS). Cooperative systems are developed by different manufacturers at different locations, which makes interoperability testing a tedious task. Up until

  3. Development of a Valid Volleyball Skills Test Battery. (United States)

    Bartlett, Jackie; And Others


    Describes the development of the North Carolina State University Volleyball Skills Test Battery which offers accurate measurement of three volleyball skills (serve, forearm pass, and set). When physical educators tested 313 students, the battery objectively measured their abilities, providing a gamelike means of teaching, testing, grouping, and…

  4. The Development of a Recombinant scFv Monoclonal Antibody Targeting Canine CD20 for Use in Comparative Medicine.

    Directory of Open Access Journals (Sweden)

    Saurabh Jain

    Full Text Available Monoclonal antibodies are leading agents for therapeutic treatment of human diseases, but are limited in use by the paucity of clinically relevant models for validation. Sporadic canine tumours mimic the features of some human equivalents. Developing canine immunotherapeutics can be an approach for modeling human disease responses. Rituximab is a pioneering agent used to treat human hematological malignancies. Biologic mimics that target canine CD20 are just being developed by the biotechnology industry. Towards a comparative canine-human model system, we have developed a novel anti-CD20 monoclonal antibody (NCD1.2 that binds both human and canine CD20. NCD1.2 has a sub-nanomolar Kd as defined by an octet red binding assay. Using FACS, NCD1.2 binds to clinically derived canine cells including B-cells in peripheral blood and in different histotypes of B-cell lymphoma. Immunohistochemical staining of canine tissues indicates that the NCD1.2 binds to membrane localized cells in Diffuse Large B-cell lymphoma, Marginal Zone Lymphoma, and other canine B-cell lymphomas. We cloned the heavy and light chains of NCD1.2 from hybridomas to determine whether active scaffolds can be acquired as future biologics tools. The VH and VL genes from the hybridomas were cloned using degenerate primers and packaged as single chains (scFv into a phage-display library. Surprisingly, we identified two scFv (scFv-3 and scFv-7 isolated from the hybridoma with bioactivity towards CD20. The two scFv had identical VH genes but different VL genes and identical CDR3s, indicating that at least two light chain mRNAs are encoded by NCD1.2 hybridoma cells. Both scFv-3 and scFv-7 were cloned into mammalian vectors for secretion in CHO cells and the antibodies were bioactive towards recombinant CD20 protein or peptide. The scFv-3 and scFv-7 were cloned into an ADEPT-CPG2 bioconjugate vector where bioactivity was retained when expressed in bacterial systems. These data identify a

  5. The Development of a Recombinant scFv Monoclonal Antibody Targeting Canine CD20 for Use in Comparative Medicine. (United States)

    Jain, Saurabh; Aresu, Luca; Comazzi, Stefano; Shi, Jianguo; Worrall, Erin; Clayton, John; Humphries, William; Hemmington, Sandra; Davis, Paul; Murray, Euan; Limeneh, Asmare A; Ball, Kathryn; Ruckova, Eva; Muller, Petr; Vojtesek, Borek; Fahraeus, Robin; Argyle, David; Hupp, Ted R


    Monoclonal antibodies are leading agents for therapeutic treatment of human diseases, but are limited in use by the paucity of clinically relevant models for validation. Sporadic canine tumours mimic the features of some human equivalents. Developing canine immunotherapeutics can be an approach for modeling human disease responses. Rituximab is a pioneering agent used to treat human hematological malignancies. Biologic mimics that target canine CD20 are just being developed by the biotechnology industry. Towards a comparative canine-human model system, we have developed a novel anti-CD20 monoclonal antibody (NCD1.2) that binds both human and canine CD20. NCD1.2 has a sub-nanomolar Kd as defined by an octet red binding assay. Using FACS, NCD1.2 binds to clinically derived canine cells including B-cells in peripheral blood and in different histotypes of B-cell lymphoma. Immunohistochemical staining of canine tissues indicates that the NCD1.2 binds to membrane localized cells in Diffuse Large B-cell lymphoma, Marginal Zone Lymphoma, and other canine B-cell lymphomas. We cloned the heavy and light chains of NCD1.2 from hybridomas to determine whether active scaffolds can be acquired as future biologics tools. The VH and VL genes from the hybridomas were cloned using degenerate primers and packaged as single chains (scFv) into a phage-display library. Surprisingly, we identified two scFv (scFv-3 and scFv-7) isolated from the hybridoma with bioactivity towards CD20. The two scFv had identical VH genes but different VL genes and identical CDR3s, indicating that at least two light chain mRNAs are encoded by NCD1.2 hybridoma cells. Both scFv-3 and scFv-7 were cloned into mammalian vectors for secretion in CHO cells and the antibodies were bioactive towards recombinant CD20 protein or peptide. The scFv-3 and scFv-7 were cloned into an ADEPT-CPG2 bioconjugate vector where bioactivity was retained when expressed in bacterial systems. These data identify a recombinant anti-CD20

  6. Development of computer simulation models for pedestrian subsystem impact tests

    NARCIS (Netherlands)

    Kant, R.; Konosu, A.; Ishikawa, H.


    The European Enhanced Vehicle-safety Committee (EEVC/WG10 and WG17) proposed three component subsystem tests for cars to assess pedestrian protection. The objective of this study is to develop computer simulation models of the EEVC pedestrian subsystem tests. These models are available to develop a

  7. Evaluation of Test-Driven Development: An Industrial Case Study

    NARCIS (Netherlands)

    Wasmus, H.; Gross, H-G.


    Test-driven development is a novel software development practice and part of the Extreme Programming paradigm. It is based on the principle that tests should be designed and written for a module iteratively, while the code of the module is devised. This is the opposite of what is usual in current so

  8. Antibodies to the quinolones and fluoroquinolones for the development of generic and specific immunoassays for detection of these residues in animal products. (United States)

    Bucknall, S; Silverlight, J; Coldham, N; Thorne, L; Jackman, R


    Several quinolone and fluoroquinolone haptens have been used to raise polyclonal antibodies exhibiting both specific and generic properties for these classes of antimicrobial compounds. The antisera have been assessed in rapid enzyme immunoassays (ELISAs) designed to exploit the specificities obtained. A direct generic ELISA for both the quinolones and fluoroquinolones has been developed that uses the cross-reactivity of an antibody raised against norfloxacin (1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid) linked to ovalbumin via a secondary amine group on the piperazinyl moiety to detect nine different drugs in these classes. Specific ELISAs to ciprofloxacin (1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid), enrofloxacin (1-cyclopropyl-7-(4-ethyl-1-piperazinyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinoline carboxylic acid), flumequin (9-fluoro-6,7-dihydro-5-methyl-1-oxo-1H,5H-benzo(ij)quinolizine-2-carboxylic acid) and nalidixic acid (1-ethyl-1,4-dihydro-7-methyl-4-oxo-1,8-naphthyridine-3-carboxylic acid) have also been developed with a high degree of specificity to the individual compounds. The assays measure drug residues in bovine milk and ovine kidney with an interassay relative standard deviation (s(r)) of 10.5% or less and intra-assay s(r) of 11.2% or less. Sensitivity is less than 4 microg x kg(-1) for both the generic and specific assays for all but one of the compounds tested. (Pipemidic acid (8-ethyl-5,8-dihydro-5-oxo-2-(1-piperazinyl)pyrido(2,3-d)pyrimidine-6-carboxylic acid) is detectable at 6 microg x kg(-1) in kidney.)

  9. Evaluation of two rK39 dipstick tests, direct agglutination test, and indirect fluorescent antibody test for diagnosis of visceral leishmaniasis in a new epidemic site in highland Ethiopia. (United States)

    Cañavate, Carmen; Herrero, Merce; Nieto, Javier; Cruz, Israel; Chicharro, Carmen; Aparicio, Pilar; Mulugeta, Abate; Argaw, Daniel; Blackstock, Anna J; Alvar, Jorge; Bern, Caryn


    We assessed the performance characteristics of two rK39 immunochromatographic tests, a direct agglutination test (DAT), and an indirect immunofluorescent antibody test (IFAT) in the site of a new epidemic of visceral leishmaniasis (VL) in northwestern Ethiopia. The study population was composed of 179 patients with suspected VL and 67 controls. The sensitivities of Kalazar Detect(®), DiaMed-IT Leish(®), DAT, and IFAT in 35 polymerase chain reaction-confirmed VL cases were 94.3%, 91.4%, 91.4%, and 100%, respectively, and the specificities were 98.5%, 94%, 98.5%, and 98.5%, respectively. In a Bayesian latent class analysis of all 246 specimens, the estimated sensitivities were 90.5%, 89%, 88.8%, and 96% for Kalazar Detect(®), DiaMed-IT Leish(®), DAT, and IFAT, respectively; DAT showed the highest estimated specificity (97.4%). Both rK39 immunochromatographic tests perform as well as DAT, and are suitable for VL diagnosis in first-level health centers in this area of Ethiopia.

  10. Evaluation of Two rK39 Dipstick Tests, Direct Agglutination Test, and Indirect Fluorescent Antibody Test for Diagnosis of Visceral Leishmaniasis in a New Epidemic Site in Highland Ethiopia (United States)

    Cañavate, Carmen; Herrero, Merce; Nieto, Javier; Cruz, Israel; Chicharro, Carmen; Aparicio, Pilar; Mulugeta, Abate; Argaw, Daniel; Blackstock, Anna J.; Alvar, Jorge; Bern, Caryn


    We assessed the performance characteristics of two rK39 immunochromatographic tests, a direct agglutination test (DAT), and an indirect immunofluorescent antibody test (IFAT) in the site of a new epidemic of visceral leishmaniasis (VL) in northwestern Ethiopia. The study population was composed of 179 patients with suspected VL and 67 controls. The sensitivities of Kalazar Detect®, DiaMed-IT Leish®, DAT, and IFAT in 35 polymerase chain reaction–confirmed VL cases were 94.3%, 91.4%, 91.4%, and 100%, respectively, and the specificities were 98.5%, 94%, 98.5%, and 98.5%, respectively. In a Bayesian latent class analysis of all 246 specimens, the estimated sensitivities were 90.5%, 89%, 88.8%, and 96% for Kalazar Detect®, DiaMed-IT Leish®, DAT, and IFAT, respectively; DAT showed the highest estimated specificity (97.4%). Both rK39 immunochromatographic tests perform as well as DAT, and are suitable for VL diagnosis in first-level health centers in this area of Ethiopia. PMID:21212210

  11. Enzyme-linked immunosorbent assay for detection of streptolysin O antibodies.


    Reitano, M; Pisano, M. A.; Eriquez, L A; D'Amato, R F


    An enzyme-linked immumosorbent assay (ELISA), based upon the detection of streptolysin O antibodies in human sera, was developed. Disposable polystyrene tubes, sensitized with streptolysin O antigen, were used as the test vehicles. Corresponding antibodies, present in test sera, were detected by binding of the antibodies to goat anti-human immunoglobulin G conjugated to horseradish peroxidase. Demonstration of bound conjugate was accomplished by monitoring peroxidase activity spectrophotometr...

  12. Rh(D)阴性献血者不规则抗体检测的结果分析%Analysis the result of irregular antibody test in Rh (D) negative donors

    Institute of Scientific and Technical Information of China (English)

    李健; 周英; 吕文彬; 陈雪; 迭敏; 龚希


    目的 分析Rh(D)阴性献血者不规则抗体检测的结果,探讨在献血者血液Rh(D)阴性确认试验时,进行不规则抗体检测的必要性.方法 用间接抗人球蛋白法进行Rh(D)阴性确认试验及抗体筛选试验、抗体鉴定试验,盐水法进行Rh表现型的检测.结果 1205份Rh(D)阴性献血员标本中,抗体筛选试验阳性的标本有20份,经过抗体鉴定,其中抗-D 10份,抗-M 6份,非特异性抗体2份,抗-Lea 1份,冷自身抗体1份.结论 Rh(D)阴性献血者抗体筛选阳性率高达1.66%,较以往报道的正常人群抗体筛选阳性率高.在临床供血上,其高检出率对临床用血安全有较为重要的意义,对Rh(D)阴性献血者更应该进行不规则抗体检测.%Objective To analyze the result of irregular antibody test in Rh (D) negatie donors, discuss in the necessity of irregular antibody test in Rh (D) negative confirmation experiment among the blood testing with Rh ( D) negative donors. Methods Rh (D) negative confirmation experiment antibody screening and antibody Identification test using indirect antiglobulin test(IAT) , The Rh phenotype were determined by saline method. Results among 120S samples of Rh (D) negative donors, 20 samples antibody screening test is positive. And after antibody Identification test, Among them 10 samples were anti- 0 , 6 samples were anti- M, 2 samples were Nonspecific antibody, 1 sample was anti- Le,l sample was cold antibody. Conclusion The positive rate of Antibody screening in Rh ( D) negative donors is 1. 66% . It is greater than Previous reports of the normal population positive antibody screening. The higher positive rate of Antibody screening has Important clinical significance in blood supply, therefore Rh ( D) negative donors more should do irregular antibody test.

  13. Development of a Colloidal Gold-based Immunochromatographic Test Strip for Detection of Cetacean Myoglobin. (United States)

    Chan, Kun-Wei; Lo, Chieh; Chu, Chi-Shih; Chin, Li-Te; Wang, Yu-Ting; Yang, Wei-Cheng


    This protocol describes the development of a colloidal gold immunochromatographic test strip based on the sandwich format that can be used to differentiate the myoglobin (Mb) of cetaceans from that of seals and other animals. The strip provides rapid and on-the-spot screening for cetacean meat, thereby restraining its illegal trade and consumption. Two monoclonal antibodies (mAbs) with reactivity toward the Mb of cetaceans were developed. The amino acid sequences of Mb antigenic reactive regions from various animals were analyzed in order to design two synthetic peptides (a general peptide and a specific peptide) and thereafter raise the mAbs (subclass IgG1). The mAbs were selected from hybridomas screened by indirect ELISA, western blot and dot blot. CGF5H9 was specific to the Mbs of rabbits, dogs, pigs, cows, goats, and cetaceans while it showed weak to no affinity to the Mbs of chickens, tuna and seals. CSF1H13 can bind seals and cetaceans with strong affinity but showed no affinity to other animals. Cetacean samples from four families (Balaenopteridae, Delphinidae, Phocoenidae and Kogiidae) were used in this study, and the results indicated that these two mAbs have broad binding ability to Mbs from different cetaceans. These mAbs were applied on a sandwich-type colloidal gold immunochromatographic test strip. CGF5H9, which recognizes many species, was colloid gold-labeled and used as the detection antibody. CSF1H13, which was coated on the test zone, detected the presence of cetacean and seal Mbs. Muscle samples from tuna, chicken, seal, five species of terrestrial mammals and 15 species of cetaceans were tested in triplicate. All cetacean samples showed positive results and all the other samples showed negative results.

  14. Comparison of a flow assay for brucellosis antibodies with the reference cELISA test in West African Bos indicus.

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    Barend M deC Bronsvoort

    Full Text Available Brucellosis is considered by the Food and Agricultural Organisation and the World Health Organisation as one of the most widespread zoonoses in the world. It is a major veterinary public health challenge as animals are almost exclusively the source of infection for people. It is often undiagnosed in both human patients and the animal sources and it is widely acknowledged that the epidemiology of brucellosis in humans and animals is poorly understood, particularly in sub-Saharan Africa. It is therefore important to develop better diagnostic tools in order to improve our understanding of the epidemiology and also for use in the field for disease control and eradication. As with any new diagnostic test, it is essential that it is validated in as many populations as possible in order to characterise its performance and improve the interpretation of its results. This paper describes a comparison between a new lateral flow assasy (LFA for bovine brucellosis and the widely used cELISA in a no gold standard analysis to estimate test performance in this West African cattle population. A Bayesian formulation of the Hui-Walter latent class model incorporated previous studies' data on sensitivity and specificity of the cELISA. The results indicate that the new LFA is very sensitive (approximately 87% and highly specific (approximately 97%. The analysis also suggests that the current cut-off of the cELSIA may not be optimal for this cattle population but alternative cut-offs did not significantly change the estimates of the LFA. This study demonstrates the potential usefulness of this simple to use test in field based surveillance and control which could be easily adopted for use in developing countries with only basic laboratory facilities.

  15. Development and evaluation of a monoclonal antibody-based inhibition ELISA for the quantification of chymosin in solution. (United States)

    Rolet-Répécaud, O; Arnould, C; Dupont, D; Gavoye, S; Beuvier, E; Achilleos, C


    Chymosin is the major enzyme of natural rennet, traditionally used in cheese making for its high milk-clotting activity. For technical reasons, an accurate characterization of rennet should include its total clotting activity and also its enzymatic composition. Monoclonal antibodies specific to chymosin were obtained from mice immunized with purified bovine chymosin, and an inhibition enzyme-linked immunosorbent assay (ELISA) was developed for the quantification of chymosin in solution. No cross-reactivity was observed with other milk-clotting enzymes commonly used in cheese making. The limit of detection and limit of quantification were 125 and 400 ng/mL, respectively. The values of precision within and among runs were 7.23 and 7.39%, respectively, and satisfying recovery, from 92 to 119%, was found for spiked samples. The inhibition ELISA was successfully applied to commercial rennets, and the results were consistent with those obtained using the standard chromatographic method (IDF 110: A, 1987).


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    Eu. V. Grishin


    Full Text Available The present study focuses on development of monoclonal antibodies (MAbs which specifically interact with cholera toxin or heat labile enterotoxin of E. coli. Such monoclonal antibodies MAbs are possessed of ability to identify cholera toxin or heat labile enterotoxin in different immunochemical assays. We obtained hybridoma clones which produced monoclonal antibodies of IgG isotypes to cholera toxin and heat labile enterotoxin. On application of the method of serial dilutions we selected the clones which produced monoclonal antibodies with specific activity against only one of the toxins. We found the 16 pairs of monoclonal antibodies to cholera toxin and 28 ones to heat labile enterotoxin. By means of these monoclonal antibodies it was possible to realize the quantitative analysis of theses toxins in sandwich immunoassay ELISA and diplex sandwich xMAP-assay. The limits of detection of cholera toxin and heat labile enterotoxin in ELISA in control buffer were 0.2 and 0.4 ng/ml, respectively, and in xMAP assay — 0.01 and 0.08 ng/ml, respectively. In probes of cow milk, meat soup, pond water and nasopharyngeal washes cholera toxin was detected in the both assays with the same limits of detections, but heat labile enterotoxin limits of detections were above the ones in control buffers.

  17. Generation of polyclonal antibody with high avidity to rosuvastatin and its use in development of highly sensitive ELISA for determination of rosuvastatin in plasma

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    Al-Malaq Hamoud A


    Full Text Available Abstract In this study, a polyclonal antibody with high avidity and specificity to the potent hypocholesterolaemic agent rosuvastatin (ROS has been prepared and used in the development of highly sensitive enzyme-linked immunosorbent assay (ELISA for determination of ROS in plasma. ROS was coupled to keyhole limpt hemocyanin (KLH and bovine serum albumin (BSA using carbodiimide reagent. ROS-KLH conjugate was used for immunization of female 8-weeks old New Zealand white rabbits. The immune response of the rabbits was monitored by direct ELISA using ROS-BSA immobilized onto microwell plates as a solid phase. The rabbit that showed the highest antibody titer and avidity to ROS was scarified and its sera were collected. The IgG fraction was isolated and purified by avidity chromatography on protein A column. The purified antibody showed high avidity to ROS; IC50 = 0.4 ng/ml. The specificity of the antibody for ROS was evaluated by indirect ELISA using various competitors from the ROS-structural analogues and the therapeutic agents used with ROS in a combination therapy. The proposed ELISA involved a competitive binding reaction between ROS, in plasma sample, and the immobilized ROS-BSA for the binding sites on a limited amount of the anti-ROS antibody. The bound anti-ROS antibody was quantified with horseradish peroxidase-labeled second anti-rabbit IgG antibody (HRP-IgG and 3,3',5,5'-tetramethylbenzidine (TMB as a substrate for the peroxidase enzyme. The concentration of ROS in the sample was quantified by its ability to inhibit the binding of the anti-ROS antibody to the immobilized ROS-BSA and subsequently the color intensity in the assay wells. The assay enabled the determination of ROS in plasma at concentrations as low as 40 pg/ml.

  18. 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)


    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.

  19. Development and validation of an indirect Enzyme-linked Immunosorbent Assay for the detection of antibodies against Schmallenberg virus in blood samples from ruminants

    NARCIS (Netherlands)

    Heijden, van der H.M.J.F.; Bouwstra, R.J.; Mars, M.H.; Poel, van der W.H.M.; Wellenberg, G.J.; Maanen, van C.


    To detect Schmallenberg virus (SBV) infections in ruminants and to perform SBV epidemiological studies a cost-effective serological test is required. For these purposes an indirect whole virus Enzyme-linked Immunosorbent Assay (ELISA) for detection of SBV specific antibodies in ruminant blood sample

  20. Phase 1 Space Fission Propulsion System Testing and Development Progress (United States)

    VanDyke, Melissa; Houts, Mike; Godfroy, Tom; Dickens, Ricky; Poston, David; Kapernick, Rick; Reid, Bob; Salvail, Pat; Ring, Peter; Schafer, Charles (Technical Monitor)


    Successful development of space fission systems requires an extensive program of affordable and realistic testing. In addition to tests related to design/development of the fission system, realistic testing of the actual flight unit must also be performed. If the system is designed to operate within established radiation damage and fuel burn up limits while simultaneously being designed to allow close simulation of heat from fission using resistance heaters, high confidence in fission system performance and lifetime can be attained through a series of non-nuclear tests. The Safe Affordable Fission Engine (SAFE) test series, whose ultimate goal is the demonstration of a 300 kW flight configuration system, has demonstrated that realistic testing can be performed using non-nuclear methods. This test series, carried out in collaboration with other NASA centers, other government agencies, industry, and universities, successfully completed a testing program with a 30 kWt core, Stirling engine, and ion engine configuration. Additionally, a 100 kWt core is in fabrication and appropriate test facilities are being reconfigured. This paper describes the current SAFE non-nuclear tests, which includes test article descriptions, test results and conclusions, and future test plans.