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Sample records for virus antibody 2g12

  1. A glycoconjugate antigen based on the recognition motif of a broadly neutralizing human immunodeficiency virus antibody, 2G12, is immunogenic but elicits antibodies unable to bind to the self glycans of gp120

    DEFF Research Database (Denmark)

    Astronomo, Rena D; Lee, Hing-Ken; Scanlan, Christopher N

    2008-01-01

    The glycan shield of human immunodeficiency virus type 1 (HIV-1) gp120 contributes to viral evasion from humoral immune responses. However, the shield is recognized by the HIV-1 broadly neutralizing antibody (Ab), 2G12, at a relatively conserved cluster of oligomannose glycans. The discovery of 2G......12 raises the possibility that a carbohydrate immunogen may be developed that could elicit 2G12-like neutralizing Abs and contribute to an AIDS vaccine. We have previously dissected the fine specificity of 2G12 and reported that the synthetic tetramannoside (Man(4)) that corresponds to the D1 arm...

  2. MABGEL 1: first phase 1 trial of the anti-HIV-1 monoclonal antibodies 2F5, 4E10 and 2G12 as a vaginal microbicide.

    Directory of Open Access Journals (Sweden)

    Georgina C Morris

    Full Text Available BACKGROUND: Monoclonal antibodies (mAbs which potently neutralize a broad range of HIV isolates are potential microbicide candidates. To date, topical application of mAbs in humans and their stability in vaginal secretions has not been studied. OBJECTIVES: To assess the pharmacokinetics and safety of the mAbs 2F5, 4E10 and 2G12 when applied vaginally in women. DESIGN: A randomized, double-blind, placebo-controlled phase 1 trial. METHODS: Twenty-eight healthy, sexually abstinent women administered 2.5 g of gel daily for 12 days containing either 10 or 20 mg/g of each mAb (MABGEL or placebo. Main clinical evaluations and sampling occurred at baseline, 1, 8, and 24 hours post-1st dose and 12 and 36 hours post-12th dose. RESULTS: After adjustment for dilution factors, median levels of 2F5, 4E10 and 2G12 in vaginal secretions at 1 hour post high-dose MABGEL were 7.74, 5.28 and 7.48 mg/ml respectively. Levels of 2F5 and 4E10 declined exponentially thereafter with similar estimated half-lives (4.6 and 4.3 hours. In contrast, 2G12 levels declined more rapidly in the first 8 hours, with an estimated half-life of 1.4 hours during this period. There was no evidence of systemic absorption. There were no significant differences in local or systemic adverse event rates or vaginal flora changes (by qPCR between active and placebo gel arms. Whilst at least 1 adverse event was recorded in 96% of participants, 95% were mild and none were serious. CONCLUSIONS: Vaginal application of 50 mg of each mAb daily was safe over a 12 day period. Median mAb concentrations detected at 8 hours post dose were potentially sufficient to block HIV transmission.2G12 exhibited more rapid elimination from the human vagina than 4E10 and 2F5, likely due to poor stability of 2G12 in acidic human vaginal secretions. Further research is needed to develop mAb-based vaginal microbicides and delivery systems. TRIAL REGISTRATION: ISRCTN 64808733 UK CRN Portfolio 6470.

  3. Hepatitis A virus antibody

    International Nuclear Information System (INIS)

    Novak, J.; Kselikova, M.; Urbankova, J.

    1980-01-01

    A description is presented of a radioimmunoassay designed to prove the presence of the antibody against the hepatitis A virus (HA Ab, anti-Ha) using an Abbott HAVAB set. This proof as well as the proof of the antibody against the nucleus of the hepatitis B virus is based on competition between a normal antibody against hepatitis A virus and a 125 I-labelled antibody for the binding sites of a specific antigen spread all over the surface of a tiny ball; this is then indirect proof of the antibody under investigation. The method is described of reading the results from the number of impulses per 60 seconds: the higher the titre of the antibody against the hepatitis A virus in the serum examined, the lower the activity of the specimen concerned. The rate is reported of incidence of the antibody against the hepatitis A virus in a total of 68 convalescents after hepatitis A; the antibody was found in 94.1%. The immunoglobulin made from the convalescents' plasma showed the presence of antibodies in dilutions as high as 1:250 000 while the comparable ratio for normal immunoglobulin Norga was only 1:2500. Differences are discussed in the time incidence of the antibodies against the hepatitis A virus, the antibodies against the surface antigen of hepatitis B, and the antibody against the nucleus of the hepatitis V virus. (author)

  4. Monoclonal antibodies against plant viruses

    International Nuclear Information System (INIS)

    Sandler, E.; Dietzgen, R.G.

    1984-01-01

    Ever since antigenic properties of plant viruses were discovered antisera have been raised and used for plant virus diagnosis and for the analysis of virus structure as well. From the early qualitative diagnosis method of precipitating the virus in clarified sap of an infected plant and the first quantitative application of the precipitin test vast progress has been made with regard to the development of highly sensitive and highly quantitative methods for virus detection. Of equal importance was the improvement of methods for separating virus from host cell components since the specificity of antisera raised against a virus could be increased by using an antigen for immunization highly concentrated and largely freed from contaminating host substances. The introduction of the enzyme-linked immunosorbent assay (ELISA) into plant virology allows detection of virus in nanogram quantities. Still, the conventionally raised antisera, no matter how pure an antigen was used for immunization, are polyclonal. They contain products of thousands of different antibody-secreting plasma cell clones which can be directed against all antigenic determinants (epitopes) of the virus, but also against antigens of the host plant that may not have been entirely separated from the immunizing virus during the purification procedure. Even after cross adsorption of polyclonal antisera some residual heterogeneity can be expected to remain. Within these boundaries the information gained with polyclonal antisera on virus structure and on virus diagnosis has to be interpreted

  5. Radioimmunoassay of measles virus antibodies in SSPE

    International Nuclear Information System (INIS)

    Jankowski, M.A.; Gut, W.; Kantoch, M.

    1982-01-01

    A sensitive radioimmunoassay (RIA) was introduced for detecting measles virus IgG and IgM antibodies. The hyperimmune response to the measles virus could be demonstrated more accurately by RIA than by haemagglutination inhibition (HI). The ratio between RIA and HI antibody titres was decidedly higher in sera and cerebrospinal fluids of patients with subacute sclerosing panencephalitis than in those of other groups tested. (author)

  6. antibodies against Herpes simplex virus

    African Journals Online (AJOL)

    171. 5. Celum, C. L. The Interaction between Herpes Sim- plex Virus and Human Immunodeficiency Virus. Her- pes, 2004; 1: 36A-44A. 6. Brown, Z.A., Selke, S., Zeh, J., Kopelman, J., Maslow,. A., Ashley, R.L., Watts, D.H., Berry, S., Herd, M. and.

  7. Radioimmunoassay of bovine leukosis virus antibodies

    International Nuclear Information System (INIS)

    Franz, J.; Hampl, J.; Svoboda, I.; Granatova, M.; Hofirek, B.; Skrobak, F.

    1986-01-01

    A RIA method was developed for identifying the presence of serum antibodies to the bovine leukosis virus. The chosen procedure uses the ability of the virus antigen to bind to the solid phase of a polystyrene carrier. The method was compared with the ELISA method and with the pseudoneutralization and immunodiffusion tests. A high level of agreement was achieved between the RIA and the ELISA methods (95%). By its accuracy the RIA method proves superior to the immunodiffusion test. (author)

  8. Radioimmunoassay of bovine leukosis virus antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Franz, J; Hampl, J; Svoboda, I; Granatova, M; Hofirek, B; Skrobak, F

    1986-08-01

    A RIA method was developed for identifying the presence of serum antibodies to the bovine leukosis virus. The chosen procedure uses the ability of the virus antigen to bind to the solid phase of a polystyrene carrier. The method was compared with the ELISA method and with the pseudoneutralization and immunodiffusion tests. A high level of agreement was achieved between the RIA and the ELISA methods (95%). By its accuracy the RIA method proves superior to the immunodiffusion test.

  9. Development and Characterization of Canine Distemper Virus Monoclonal Antibodies.

    Science.gov (United States)

    Liu, Yuxiu; Hao, Liying; Li, Xiangdong; Wang, Linxiao; Zhang, Jianpo; Deng, Junhua; Tian, Kegong

    2017-06-01

    Five canine distemper virus monoclonal antibodies were developed by immunizing BALB/c mice with a traditional vaccine strain Snyder Hill. Among these monoclonal antibodies, four antibodies recognized both field and vaccine strains of canine distemper virus without neutralizing ability. One monoclonal antibody, 1A4, against hemagglutinin protein of canine distemper virus was found to react only with vaccine strain virus but not field isolates, and showed neutralizing activity to vaccine strain virus. These monoclonal antibodies could be very useful tools in the study of the pathogenesis of canine distemper virus and the development of diagnostic reagents.

  10. Mathematical analysis of dengue virus antibody dynamics

    Science.gov (United States)

    Perera, Sulanie; Perera, SSN

    2018-03-01

    Dengue is a mosquito borne viral disease causing over 390 million infections worldwide per annum. Even though information on how infection is controlled and eradicated from the body is lacking, antibodies are thought to play a major role in clearing the virus. In this paper, a non-linear conceptual dynamical model with humoral immune response and absorption effect has been proposed for primary dengue infection. We have included the absorption of pathogens into uninfected cells since this effect causes the virus density in the blood to decrease. The time delay that arises in the production of antibodies was accounted and is introduced through a continuous function. The basic reproduction number R0 is computed and a detailed stability analysis is done. Three equilibrium states, namely the infection free equilibrium, no immune equilibrium and the endemic equilibrium were identified and the existence and the stability conditions of these steady states were obtained. Numerical simulations proved the results that were obtained. By establishing the characteristic equation of the model at infection free equilibrium, it was observed that the infection free equilibrium is locally asymptotically stable if R0 1. Stability regions are identified for infection free equilibrium state with respect to the external variables and it is observed as the virus burst rate increases, the stability regions would decrease. These results implied that for higher virus burst rates, other conditions in the body must be strong enough to eliminate the disease completely from the host. The effect of time delay of antibody production on virus dynamics is discussed. It was seen that as the time delay in production of antibodies increases, the time for viral decline also increased. Also it was observed that the virus count goes to negligible levels within 7 - 14 days after the onset of symptoms as seen in dengue infections.

  11. Antibody neutralization of retargeted measles viruses

    Science.gov (United States)

    Lech, Patrycja J.; Pappoe, Roland; Nakamura, Takafumi; Tobin, Gregory J.; Nara, Peter L.; Russell, Stephen J.

    2014-01-01

    The measles virus (MV) vaccine lineage is a promising oncolytic but prior exposure to the measles vaccine or wild-type MV strains limits treatment utility due to the presence of anti-measles antibodies. MV entry can be redirected by displaying a polypeptide ligand on the Hemagglutinin (H) C-terminus. We hypothesized that retargeted MV would escape neutralization by monoclonal antibodies (mAbs) recognizing the H receptor-binding surface and be less susceptible to neutralization by human antisera. Using chimeric H proteins, with and without mutations that ablate MV receptor binding, we show that retargeted MVs escape mAbs that target the H receptor-binding surface by virtue of mutations that ablate infection via SLAM and CD46. However, C-terminally displayed domains do not mediate virus entry in the presence of human antibodies that bind to the underlying H domain. In conclusion, utility of retargeted oncolytic measles viruses does not extend to evasion of human serum neutralization. PMID:24725950

  12. Seroprevalence of Marek's Disease Virus antibody in some poultry ...

    African Journals Online (AJOL)

    This study reports a survey of Marek's disease virus (MDV) antibody done in 21 selected poultry flocks in Lagos, Ogun and Oyo states of southwestern Nigeria. A total of 315 serum samples were examined using the Enzyme Linked Immunosorbent Assay (ELISA) technique. Marek's disease virus antibody was present in ...

  13. Identification and typing of herpes simplex viruses with monoclonal antibodies.

    OpenAIRE

    Balachandran, N; Frame, B; Chernesky, M; Kraiselburd, E; Kouri, Y; Garcia, D; Lavery, C; Rawls, W E

    1982-01-01

    Monoclonal antibodies which reacted with type-specific antigens of herpes simplex virus type 2 or with antigens shared by herpes simplex virus types 1 and 2 were used in an indirect immunofluorescence assay to type virus isolates and to detect viral antigens in cells obtained from herpetic lesions. Complete concordance was obtained for 42 isolates typed by endonuclease restriction analysis of viral DNA and by indirect immunofluorescence with monoclonal antibodies. Examination of a limited num...

  14. Monoclonal antibodies directed to E1 glycoprotein of rubella virus

    International Nuclear Information System (INIS)

    Umino, Y.; Sato, A.; Katow, S.; Matsuno, T.; Sugiura, A.

    1985-01-01

    We have prepared four monoclonal antibodies to rubella virus E1 glycoprotein. Three nonoverlapping antigenic sites were delineated on E1 protein by competitive binding assays. Antibodies binding to one site were characterized by high hemagglutination inhibition (HI) titer but poor neutralizing activity. The addition of antiglobulin conferred neutralizing activity. Antibodies directed to two other antigenic sites had modest hemolysis inhibition but little or no HI and neutralizing activities. The addition of antiglobulin markedly augmented HI activity but had little effect on neutralizing activity. Epitopes defined by three antibodies were conserved among four rubella virus strains examined. (Author)

  15. rapid assessment of polio virus antibodies prevalence amongst

    African Journals Online (AJOL)

    ISSN 1597-6343. Polio Virus Antibodies Prevalence Amongst Children In Kano State ... poliovirus serotypes (types 1, 2 or 3) which cause poliomyelitis. They are spread by ..... all those that have contributed to the overall success of this work.

  16. Radioimmunoassay for antibodies to rubella virus and its ribonucleoprotein component

    International Nuclear Information System (INIS)

    Ho-Terry, L.; Cohen, A.

    1979-01-01

    Using a radioimmune precipitation technique, the antibody response to intact rubella virus and its ribonucleoprotein component was measured. The method was very sensitive and reproducible, and did not require preliminary serum fractionation for the identification of antibodies of different immunoglobulin classes. The results showed that the IgA and IgG antibodies against the intact virus persisted in the sera of patients long after the initial infection. In contrast, IgA and IgG antibodies against the ribonucleoprotein component of rubella virus were detected only in sera of patients after recent rubella infection. This observation suggested that a test for antibodies to the ribonucleoprotein component may provide additional evidence in the diagnosis of recent rubella infection. This could be potentially a useful test particularly in the management of pregnant patients. (U.K.)

  17. Lack of Durable Cross-Neutralizing Antibodies Against Zika Virus from Dengue Virus Infection.

    Science.gov (United States)

    Collins, Matthew H; McGowan, Eileen; Jadi, Ramesh; Young, Ellen; Lopez, Cesar A; Baric, Ralph S; Lazear, Helen M; de Silva, Aravinda M

    2017-05-01

    Cross-reactive antibodies elicited by dengue virus (DENV) infection might affect Zika virus infection and confound serologic tests. Recent data demonstrate neutralization of Zika virus by monoclonal antibodies or human serum collected early after DENV infection. Whether this finding is true in late DENV convalescence (>6 months after infection) is unknown. We studied late convalescent serum samples from persons with prior DENV or Zika virus exposure. Despite extensive cross-reactivity in IgG binding, Zika virus neutralization was not observed among primary DENV infections. We observed low-frequency (23%) Zika virus cross-neutralization in repeat DENV infections. DENV-immune persons who had Zika virus as a secondary infection had distinct populations of antibodies that neutralized DENVs and Zika virus, as shown by DENV-reactive antibody depletion experiments. These data suggest that most DENV infections do not induce durable, high-level Zika virus cross-neutralizing antibodies. Zika virus-specific antibody populations develop after Zika virus infection irrespective of prior DENV immunity.

  18. Production of yam mosaic virus monoclonal antibodies in mice ...

    African Journals Online (AJOL)

    Administrator

    2011-09-19

    Sep 19, 2011 ... 4AVRDC-The World Vegetable Center, Shanhua, Taiwan. Accepted 11 August, 2011. Yam mosaic virus (YMV) ... leaves and non-infected tissue culture yam leaves. The antibody produced had a titre of ... systems for in-vitro production of monoclonal antibodies, such as standard tissue culture techniques,.

  19. Prevalence of Newcastle disease virus antibodies in sera and eggs ...

    African Journals Online (AJOL)

    ADEYEYE

    2016-03-07

    Mar 7, 2016 ... The seroprevalence and maternal antibody profiles to Newcastle disease virus infection of guinea fowls were studied using ..... gallisepticum. Avian diseases, 28 (4): 877-883. Sa'idu L, Tekdek LB & Abdu PA (2004). Prevalence of ND antibodies in domestic and semi domestic birds in Zaria, Nigeria.

  20. Monoclonal antibodies to Herpes Simplex Virus Type 2

    International Nuclear Information System (INIS)

    McLean-Pieper, C.S.

    1982-01-01

    In this thesis the production and characterisation of monoclonal antibodies to Herpes Simplex Virus Type 2 is described. The development of a suitable radioimmunoassay for the detection of anti-HSV-2 antibodies, and the selection of an optimal immunisation schedule, is given. Three assay systems are described and their reliability and sensitivity compared. (Auth.)

  1. A radioimmunoassay for anti-virus antibodies in farm animals

    International Nuclear Information System (INIS)

    Rodak, L.; Smid, B.; Sedlacek, M.

    1978-01-01

    A radioimmunoassay for determination of antibodies to Aujeszky's disease virus in piq serum is described. The results show a number of advantaqes of this method over the routinely employed virus-neutralization test. The possibility of using the RIA method in diagnosing other viral diseases of farm animals is suggested. (authors)

  2. Radioimmunoassay of Herpes simplex virus antibody: correlation with ganglionic infection

    International Nuclear Information System (INIS)

    Forghani, B.; Klassen, T.; Baringer, J.R.

    1977-01-01

    Results of herpes simplex virus (HSV) isolation from a series of human post-mortem trigeminal thoracic and sacral ganglia were correlated with HSV antibody type(s) detected in the sera by radioimmunoassay (RIA). HSV type I was isolated from trigeminal ganglia of 44 out of 90 individuals, from thoracic ganglia of 1 out of 25, and from sacral ganglia of 1 out of 68 cases. HSV type was recovered from sacral ganglia of 8 out of 68 individuals. In all cases in which an HSV was isolated from ganglia and was available for testing, homologous, type-specific antibody was demonstrable, and in a few instances antibody to the heterologous HSV was also detected. In those individuals in which HSV type I was isolated from trigeminal ganglia and HSV type 2 from sacral ganglia, antibody to both virus types was present in the sera, indicating that simultaneous latent infections with each of the two viruses can occur, and that antibody is produced to each virus independently. Antibody to HSV type 1, 2 or both types was demonstrated in 8 out of 10 cases in which virus isolation attempts were negative, suggesting either a higher sensitivity of RIA for detecting HSV infection, or the presence of latent HSV at some other site in the body which was not sampled. (author)

  3. Neutralisation and binding of VHS virus by monovalent antibody fragments

    DEFF Research Database (Denmark)

    Cupit, P.M.; Lorenzen, Niels; Strachan, G.

    2001-01-01

    We have previously reported the cloning and characterisation of the heavy and light chain variable domain genes encoding three monoclonal antibodies (Mabs) that bind viral haemorrhagic septicaemia virus (VHSV). Two of these antibodies, 3F1H10 and 3F1A2 both neutralised the virus though 3F1A2...... appeared to recognise a broader range of virus isolates. The variable domains of these two antibodies differ by only four residues (Lorenzen et al., 2000a. Fish Shellfish Immunol. 10, 129-142). To further study the mechanism of neutralisation, Fab fragments as well as a series of recombinant bacterial...... single chain antibody (scAb) fragments were generated from the three anti-VHSV Mabs and their variable domain genes, respectively. Fabs and scAbs derived from the neutralising Mabs were both able to neutralise the VHSV type 1 isolate DK-F1. In addition, a series of scAb fragments were produced using...

  4. Swine Influenza Virus Antibodies in Humans, Western Europe, 2009

    Science.gov (United States)

    Gerloff, Nancy A.; Kremer, Jacques R.; Charpentier, Emilie; Sausy, Aurélie; Olinger, Christophe M.; Weicherding, Pierre; Schuh, John; Van Reeth, Kristien

    2011-01-01

    Serologic studies for swine influenza viruses (SIVs) in humans with occupational exposure to swine have been reported from the Americas but not from Europe. We compared levels of neutralizing antibodies against 3 influenza viruses—pandemic (H1N1) 2009, an avian-like enzootic subtype H1N1 SIV, and a 2007–08 seasonal subtype H1N1—in 211 persons with swine contact and 224 matched controls in Luxembourg. Persons whose profession involved contact with swine had more neutralizing antibodies against SIV and pandemic (H1N1) 2009 virus than did the controls. Controls also had antibodies against these viruses although exposure to them was unlikely. Antibodies against SIV and pandemic (H1N1) 2009 virus correlated with each other but not with seasonal subtype H1N1 virus. Sequential exposure to variants of seasonal influenza (H1N1) viruses may have increased chances for serologic cross-reactivity with antigenically distinct viruses. Further studies are needed to determine the extent to which serologic responses correlate with infection. PMID:21392430

  5. Lichen planus, liver kidney microsomal (LKM1) antibodies and hepatitis C virus antibodies.

    Science.gov (United States)

    Divano, M C; Parodi, A; Rebora, A

    1992-01-01

    No anti-liver kidney microsomal (LKM1) antibodies were detected in 46 patients with LP, 16 of whom had also a chronic liver disease (CLD). In contrast, anti-hepatitis C virus (HCV) antibodies were found in 10% of patients with LP and in 50% of those with LP and CLD. Anti-HCV antibodies may be considered as a false-positive reaction in 56% of cases, especially when anti-LKM1 antibodies are present. Our findings do not support such a hypothesis, but suggest that CLD in LP patients is, at least in Italy, mostly a postviral chronic active hepatitis.

  6. Antiphospholipid antibodies in Brazilian hepatitis C virus carriers

    Directory of Open Access Journals (Sweden)

    A.M. Atta

    2008-06-01

    Full Text Available Hepatitis C, a worldwide viral infection, is an important health problem in Brazil. The virus causes chronic infection, provoking B lymphocyte dysfunction, as represented by cryoglobulinemia, non-organ-specific autoantibody production, and non-Hodgkin's lymphoma. The aim of this research was to screen for the presence of antiphospholipid autoantibodies in 109 Brazilian hepatitis C virus carriers without clinical history of antiphospholipid syndrome. Forty healthy individuals were used as the control group. IgA, IgG, and IgM antibodies against cardiolipin and β2-glycoprotein I were measured with an enzyme-linked immunosorbent assay, using a cut-off point of either 20 UPL or 20 SBU. While 24 (22.0% hepatitis C carriers had moderate titers of IgM anticardiolipin antibodies (median, 22.5 MPL; 95%CI: 21.5-25.4 MPL, only three carriers (<3% had IgG anticardiolipin antibodies (median, 23 GPL; 95%CI: 20.5-25.5 GPL. Furthermore, IgA anticardiolipin antibodies were not detected in these individuals. Male gender and IgM anticardiolipin seropositivity were associated in the hepatitis C group (P = 0.0004. IgA anti-β2-glycoprotein-I antibodies were detected in 29 of 109 (27.0% hepatitis C carriers (median, 41 SAU; 95%CI: 52.7-103.9 SAU. Twenty patients (18.0% had IgM anti-β2-glycoprotein I antibodies (median, 27.6 SMU; 95%CI: 23.3-70.3 SMU, while two patients had IgG antibodies against this protein (titers, 33 and 78 SGU. Antiphospholipid antibodies were detected in only one healthy individual, who was seropositive for IgM anticardiolipin. We concluded that Brazilian individuals chronically infected with hepatitis C virus present a significant production of antiphospholipid antibodies, mainly IgA anti-β2-glycoprotein I antibodies, which are not associated with clinical manifestations of antiphospholipid syndrome.

  7. Microculture system for detection of Newcastle disease virus antibodies.

    Science.gov (United States)

    Wooley, R E; Brown, J; Gratzek, J B; Kleven, S H; Scott, T A

    1974-05-01

    A microculture system utilizing cytopathic effect (CPE) and hemadsorption (HAd) end points was effective in determining the level of Newcastle disease virus (NDV) antibodies. The microculture system was of comparable sensitivity to the plaque reduction test for the detection of NDV antibodies. The standards by which the CPE and HAd microculture tests would be considered reproducible were defined. The results indicate that the CPE and HAd microculture tests are reproducible within one twofold dilution.

  8. Respiratory syncytial virus neutralizing antibodies in cord blood, respiratory syncytial virus hospitalization, and recurrent wheeze

    DEFF Research Database (Denmark)

    Stensballe, Lone Graff; Ravn, Henrik; Kristensen, Kim

    2008-01-01

    BACKGROUND: Respiratory syncytial virus (RSV) hospitalization is associated with wheeze. OBJECTIVE: To examine the influence of maternally derived RSV neutralizing antibodies in cord blood on RSV hospitalization and recurrent wheeze in infancy. METHODS: Among children from the Danish National Birth...

  9. Assay for Serum Antibodies to Infectious Bursal Disease Virus in ...

    African Journals Online (AJOL)

    Infectious bursal disease (IBD) is an acute, lymphocidal disease that has been a threat to poultry production in Nigeria and a major disease problem of poultry producing areas of the world. A serological detection of antibodies to the virus was conducted on 300 sera samples derived from local chickens slaughtered at Sheik ...

  10. Seroprevalence of Hepatitis C Virus (HCV) antibodies in pregnant ...

    African Journals Online (AJOL)

    Background: Hepatitis C virus (HCV) infection is a major public health concern. The aim of this study was to ascertain the seroprevalence and risk factors of HCV antibodies among pregnant women in Anyigba, Kogi State North Central Nigeria. Materials and methods:Blood samples (5mls) were collected from one hundred ...

  11. Screening response to hepatitis c virus antibodies among diabetic ...

    African Journals Online (AJOL)

    Epidemiological studies have suggested that hepatitis C virus (HCV) infection is a risk factor for the development of diabetes mellitus (DM) type 2; hence, this study was carried out to investigate the prevalence of HCV antibodies among diabetic patients attending the University of Ilorin Teaching Hospital (UITH), Ilorin, north ...

  12. Seroprevalence of hepatitis C virus antibodies amongst blood ...

    African Journals Online (AJOL)

    Background: Hepatitis C virus (HCV) is one of the most common transfusion transmissible infections hence the introduction of routine screening for its antibodies in blood donors in most blood banks. Methods: This was a retrospective study in which the blood donor screening register for all intending donors were reviewed ...

  13. Prevalence of Hepatitis C virus antibody among undergraduates in ...

    African Journals Online (AJOL)

    Background: This study was conducted to determine the prevalence of hepatitis C virus antibody (anti-HCV), among a healthy university undergraduate population in south-western Nigeria. Materials and Methods: Relevant medical information of students who underwent the post-admission screening exercise for the year ...

  14. Seroprevalence of Anti-Dengue Virus 2 Serocomplex antibodies in ...

    African Journals Online (AJOL)

    Introduction: There has been a recent increase in the spread of dengue to rural areas. Rural parts of western kenya are naturally prone to mosquito-borne diseases, however, limited research has been documented on infections with dengue. This study therefore investigated the presence of antibodies against dengue virus ...

  15. antibodies against Herpes simplex virus (HSV)

    African Journals Online (AJOL)

    Chi-square analysis was used to determine the association of infection with ... tibody. No statistical association existed between the prevalence of HSV-1&-2 IgG antibodies and the socio-demographic variables ... concern, established by the widespread of genital HSV .... Chi-square test was employed to define relationships.

  16. Human immunodeficiency virus (HIV) specific antibodies among ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-03-20

    Mar 20, 2009 ... Key words: HIV-1/2 antibody prevalence, pregnant women, commercial sex workers, risk factors, Nigeria. INTRODUCTION. There are two .... Africa. However, among Japanese and Chilean female. SWs, Miyazaki et al. .... STIs (P = 0.0001, OR = 6.0), level of education (P = 0.0001, OR = 40.7) and age (P ...

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

    Science.gov (United States)

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

    2018-01-01

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

  18. Antibody Derived Peptides for Detection of Ebola Virus Glycoprotein.

    Directory of Open Access Journals (Sweden)

    Luis Mario Rodríguez-Martínez

    Full Text Available Current Ebola virus (EBOV detection methods are costly and impractical for epidemic scenarios. Different immune-based assays have been reported for the detection and quantification of Ebola virus (EBOV proteins. In particular, several monoclonal antibodies (mAbs have been described that bind the capsid glycoprotein (GP of EBOV GP. However, the currently available platforms for the design and production of full-length mAbs are cumbersome and costly. The use of antibody fragments, rather than full-length antibodies, might represent a cost-effective alternative for the development of diagnostic and possibly even therapeutic alternatives for EBOV.We report the design and expression of three recombinant anti-GP mAb fragments in Escherichia coli cultures. These fragments contained the heavy and light variable portions of the three well-studied anti-GP full-length mAbs 13C6, 13F6, and KZ52, and are consequently named scFv-13C6, scFv-13F6, and Fab-KZ52, respectively. All three fragments exhibited specific anti-GP binding activity in ELISA experiments comparable to that of full-length anti-GP antibodies (i.e., the same order of magnitude and they are easily and economically produced in bacterial cultures.Antibody fragments might represent a useful, effective, and low cost alternative to full-length antibodies in Ebola related capture and diagnostics applications.

  19. Antibody-mediated immunotherapy against chronic hepatitis B virus infection.

    Science.gov (United States)

    Gao, Ying; Zhang, Tian-Ying; Yuan, Quan; Xia, Ning-Shao

    2017-08-03

    The currently available drugs to treat hepatitis B virus (HBV) infection include interferons and nucleos(t)ide analogs, which can only induce disease remission and are inefficient for the functional cure of patients with chronic HBV infection (CHB). Since high titers of circulating hepatitis B surface antigen (HBsAg) may be essential to exhaust the host anti-HBV immune response and they cannot be significantly reduced by current drugs, new antiviral strategies aiming to suppress serum hepatitis B surface antigen (HBsAg) could help restore virus-specific immune responses and promote the eradication of the virus. As an alternative strategy, immunotherapy with HBsAg-specific antibodies has shown some direct HBsAg suppression effects in several preclinical and clinical trial studies. However, most described previously HBsAg-specific antibodies only had very short-term HBsAg suppression effects in CHB patients and animal models mimicking persistent HBV infection. More-potent antibodies with long-lasting HBsAg clearance effects are required for the development of the clinical application of antibody-mediated immunotherapy for CHB treatment. Our recent study described a novel mAb E6F6 that targets a unique epitope on HBsAg. It could durably suppress the levels of HBsAg and HBV DNA via Fcγ receptor-dependent phagocytosis in vivo. In this commentary, we summarize the current research progress, including the therapeutic roles and mechanisms of antibody-mediated HBV clearance as well as the epitope-determined therapeutic potency of the antibody. These insights may provide some clues and guidance to facilitate the development of therapeutic antibodies against persistent viral infection.

  20. [Production of monoclonal antibodies against a wild strain of rabies virus].

    Science.gov (United States)

    Akacem, O; Benmansour, A; Coulon, P; Brahimi, M; Benhassine, M

    1992-01-01

    Production of monoclonal antibodies against a wild strain of rabies virus. Cell fusion of SP 2/O, a murine myeloma against a wild strain of rabies virus has originated five monoclonal antibodies (M.A.) specific for virus nucleocapsid , one M.A. specific for virus glycoprotein and one M.A. specific for a viral membrane protein.

  1. Human immunodeficiency virus (HIV) specific antibodies among ...

    African Journals Online (AJOL)

    obtained from each sample was tested using parallel testing algorithm with DETERMINE® HIV-1/2 and HIV-1/2 STAT-PAK® test was used for statistical analysis of the data. The overall prevalence of HIV-1/2 antibodies was 29.1% (n = 199). Seroprevalence of 39.4 and 19.0% were observed for the CSWs and the PW, ...

  2. Antibody escape kinetics of equine infectious anemia virus infection of horses.

    Science.gov (United States)

    Schwartz, Elissa J; Nanda, Seema; Mealey, Robert H

    2015-07-01

    Lentivirus escape from neutralizing antibodies (NAbs) is not well understood. In this work, we quantified antibody escape of a lentivirus, using antibody escape data from horses infected with equine infectious anemia virus. We calculated antibody blocking rates of wild-type virus, fitness costs of mutant virus, and growth rates of both viruses. These quantitative kinetic estimates of antibody escape are important for understanding lentiviral control by antibody neutralization and in developing NAb-eliciting vaccine strategies. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. Neutralizing Antibodies and Pathogenesis of Hepatitis C Virus Infection

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    Françoise Stoll-Keller

    2012-10-01

    Full Text Available Hepatitis C virus (HCV infection is a major cause of chronic liver disease worldwide. The interplay between the virus and host innate and adaptive immune responses determines the outcome of infection. There is increasing evidence that host neutralizing responses play a relevant role in the resulting pathogenesis. Furthermore, viral evasion from host neutralizing antibodies has been revealed to be an important contributor in leading both to viral persistence in acute liver graft infection following liver transplantation, and to chronic viral infection. The development of novel model systems to study HCV entry and neutralization has allowed a detailed understanding of the molecular mechanisms of virus-host interactions during antibody-mediated neutralization. The understanding of these mechanisms will ultimately contribute to the development of novel antiviral preventive strategies for liver graft infection and an urgently needed vaccine. This review summarizes recent concepts of the role of neutralizing antibodies in viral clearance and protection, and highlights consequences of viral escape from neutralizing antibodies in the pathogenesis of HCV infection.

  4. Neonatal respiratory syncytial virus infection: role of transplacentally and breast milk-acquired antibodies.

    OpenAIRE

    Wong, D T; Ogra, P L

    1986-01-01

    The effect of transplacentally and breast milk-acquired antibodies on respiratory syncytial virus infection was studied in neonatal and 2-month-old cotton rats. Adult female rats infected intranasally with live virus regularly produced virus-specific antibodies in the serum, colostrum, and breast milk. By using foster feeding techniques, we showed that both transplacentally and breast milk-acquired antibodies were effective in reducing the replication of respiratory syncytial virus in the lun...

  5. Induction of human immunodeficiency virus neutralizing antibodies using fusion complexes.

    Science.gov (United States)

    Zipeto, Donato; Matucci, Andrea; Ripamonti, Chiara; Scarlatti, Gabriella; Rossolillo, Paola; Turci, Marco; Sartoris, Silvia; Tridente, Giuseppe; Bertazzoni, Umberto

    2006-05-01

    Human immunodeficiency virus-1 (HIV-1) infects cells by membrane fusion that is mediated by the envelope proteins gp120/gp41 and the cellular receptors CD4 and CCR5. During this process, some conserved viral epitopes are temporarily exposed and may induce a neutralizing antibody response when fixed in the fusogenic conformation. These transient structures are conserved and may be effective antigens for use in an anti-HIV-1 vaccine. In this study we tested different conditions of preparation of fusion complexes inducing neutralizing antibodies against both R5 and X4 tropic HIV-1 strains. Cell lines expressing HIV-1 gp120/gp41 and CD4-CCR5 were prepared and conditions for producing fusion complexes were tested. Complexes produced at different temperature and fixative combinations were used to immunize mice. Results indicated that (a) fusion complexes prepared at either 21 degrees C, 30 degrees C or 37 degrees C were immunogenic and induced neutralizing antibodies against both R5 and X4 HIV-1 heterologous isolates; (b) after extensive purification of antibodies there was no cytotoxic effect; (c) complexes prepared at 37 degrees C were more immunogenic and induced higher titers of neutralizing antibodies than complexes prepared at either 21 degrees C or 30 degrees C; (d) the fixative used did not affect the titer of neutralizing antibodies except for glutaraldehyde which was ineffective; (e) the neutralizing activity was retained after CD4-CCR5 antibody removal. The production of higher titers of neutralizing antibody with fusion complexes prepared at 37 degrees C, as compared to lower temperatures, may be related to the induction of antibodies against many different conformation intermediates that subsequently act synergistically at different steps in the fusion process.

  6. Initiating a watch list for Ebola virus antibody escape mutations

    OpenAIRE

    Craig R. Miller; Erin L. Johnson; Aran Z. Burke; Kyle P. Martin; Tanya A. Miura; Holly A. Wichman; Celeste J. Brown; F. Marty Ytreberg

    2016-01-01

    The 2014 Ebola virus (EBOV) outbreak in West Africa is the largest in recorded history and resulted in over 11,000 deaths. It is essential that strategies for treatment and containment be developed to avoid future epidemics of this magnitude. With the development of vaccines and antibody-based therapies using the envelope glycoprotein (GP) of the 1976 Mayinga strain, one important strategy is to anticipate how the evolution of EBOV might compromise these efforts. In this study we have initiat...

  7. Post-infection immunodeficiency virus control by neutralizing antibodies.

    Directory of Open Access Journals (Sweden)

    Hiroyuki Yamamoto

    Full Text Available BACKGROUND: Unlike most acute viral infections controlled with the appearance of virus-specific neutralizing antibodies (NAbs, primary HIV infections are not met with such potent and early antibody responses. This brings into question if or how the presence of potent antibodies can contribute to primary HIV control, but protective efficacies of antiviral antibodies in primary HIV infections have remained elusive; and, it has been speculated that even NAb induction could have only a limited suppressive effect on primary HIV replication once infection is established. Here, in an attempt to answer this question, we examined the effect of passive NAb immunization post-infection on primary viral replication in a macaque AIDS model. METHODS AND FINDINGS: The inoculums for passive immunization with simian immunodeficiency virus mac239 (SIVmac239-specific neutralizing activity were prepared by purifying polyclonal immunoglobulin G from pooled plasma of six SIVmac239-infected rhesus macaques with NAb induction in the chronic phase. Passive immunization of rhesus macaques with the NAbs at day 7 after SIVmac239 challenge resulted in significant reduction of set-point plasma viral loads and preservation of central memory CD4 T lymphocyte counts, despite the limited detection period of the administered NAb responses. Peripheral lymph node dendritic cell (DC-associated viral RNA loads showed a remarkable peak with the NAb administration, and DCs stimulated in vitro with NAb-preincubated SIV activated virus-specific CD4 T lymphocytes in an Fc-dependent manner, implying antibody-mediated virion uptake by DCs and enhanced T cell priming. CONCLUSIONS: Our results present evidence indicating that potent antibody induction post-infection can result in primary immunodeficiency virus control and suggest direct and indirect contribution of its absence to initial control failure in HIV infections. Although difficulty in achieving requisite neutralizing titers for

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

    Science.gov (United States)

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

    2017-10-01

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

  9. Duration of Maternal Antibodies against Canine Distemper Virus and Hendra Virus in Pteropid Bats

    Science.gov (United States)

    Zambrana-Torrelio, Carlos; Middleton, Deborah; Barr, Jennifer A.; DuBovi, Edward; Boyd, Victoria; Pope, Brian; Todd, Shawn; Crameri, Gary; Walsh, Allyson; Pelican, Katey; Fielder, Mark D.; Davies, Angela J.; Wang, Lin-Fa; Daszak, Peter

    2013-01-01

    Old World frugivorous bats have been identified as natural hosts for emerging zoonotic viruses of significant public health concern, including henipaviruses (Nipah and Hendra virus), Ebola virus, and Marburg virus. Epidemiological studies of these viruses in bats often utilize serology to describe viral dynamics, with particular attention paid to juveniles, whose birth increases the overall susceptibility of the population to a viral outbreak once maternal immunity wanes. However, little is understood about bat immunology, including the duration of maternal antibodies in neonates. Understanding duration of maternally derived immunity is critical for characterizing viral dynamics in bat populations, which may help assess the risk of spillover to humans. We conducted two separate studies of pregnant Pteropus bat species and their offspring to measure the half-life and duration of antibodies to 1) canine distemper virus antigen in vaccinated captive Pteropus hypomelanus; and 2) Hendra virus in wild-caught, naturally infected Pteropus alecto. Both of these pteropid bat species are known reservoirs for henipaviruses. We found that in both species, antibodies were transferred from dam to pup. In P. hypomelanus pups, titers against CDV waned over a mean period of 228.6 days (95% CI: 185.4–271.8) and had a mean terminal phase half-life of 96.0 days (CI 95%: 30.7–299.7). In P. alecto pups, antibodies waned over 255.13 days (95% CI: 221.0–289.3) and had a mean terminal phase half-life of 52.24 days (CI 95%: 33.76–80.83). Each species showed a duration of transferred maternal immunity of between 7.5 and 8.5 months, which was longer than has been previously estimated. These data will allow for more accurate interpretation of age-related Henipavirus serological data collected from wild pteropid bats. PMID:23826322

  10. Neutralising antibodies for Mayaro virus in Pantanal, Brazil

    Directory of Open Access Journals (Sweden)

    Alex Pauvolid-Corrêa

    2015-02-01

    Full Text Available The Pantanal hosts diverse wildlife species and therefore is a hotspot for arbovirus studies in South America. A serosurvey for Mayaro virus (MAYV, eastern (EEEV, western (WEEV and Venezuelan (VEEV equine encephalitis viruses was conducted with 237 sheep, 87 free-ranging caimans and 748 equids, including 37 collected from a ranch where a neurologic disorder outbreak had been recently reported. Sera were tested for specific viral antibodies using plaque-reduction neutralisation test. From a total of 748 equids, of which 264 were immunised with vaccine composed of EEEV and WEEV and 484 had no history of immunisation, 10 (1.3% were seropositive for MAYV and two (0.3% for VEEV using criteria of a ≥ 4-fold antibody titre difference. Among the 484 equids without history of immunisation, 48 (9.9% were seropositive for EEEV and four (0.8% for WEEV using the same criteria. Among the sheep, five were sero- positive for equine encephalitis alphaviruses, with one (0.4% for EEEV, one (0.4% for WEEV and three (1.3% for VEEV. Regarding free-ranging caimans, one (1.1% and three (3.4%, respectively, had low titres for neutralising antibodies to VEEV and undetermined alphaviruses. The neurological disorder outbreak could not be linked to the alphaviruses tested. Our findings represent strong evidence that MAYV and all equine encephalitis alphaviruses circulated in the Pantanal.

  11. Hepatitis E virus antibody prevalence in wildlife in Poland.

    Science.gov (United States)

    Larska, M; Krzysiak, M K; Jabłoński, A; Kęsik, J; Bednarski, M; Rola, J

    2015-03-01

    Hepatitis E is an important public health problem mostly in developing but occasionally also in industrialized countries. Domestic and wildlife animals are considered reservoirs of the hepatitis E virus (HEV). Since no information on the prevalence of autochthonous HEV infections in human and animal in Poland is available, the aim of the study was to investigate the HEV seroprevalence of different wildlife species as potential virus reservoirs in the country. No HEV antibodies were found in any of the sera collected from the red deer (Cervus elaphus), European bison (Bison bonasus), roe deer (Capreolus capreolus), elk (Alces alces), fallow deer (Dama dama), sika deer (Cervus nippon), Tatra chamois (Rupicapra rupicapra tatrica) or brown bear (Ursus arctos). HEV-specific antibodies were detected in 44.4% (95% CI 38.3-50.7) serum samples originated only from wild boars. The percentage of seropositive wild boars differed significantly between the provinces and was positively correlated with the wild boar density and rurality of the area. This study showed that HEV circulates among wild boar population in Poland, and this species should be considered as an important reservoir of the virus. © 2014 Blackwell Verlag GmbH.

  12. Initiating a watch list for Ebola virus antibody escape mutations

    Directory of Open Access Journals (Sweden)

    Craig R. Miller

    2016-02-01

    Full Text Available The 2014 Ebola virus (EBOV outbreak in West Africa is the largest in recorded history and resulted in over 11,000 deaths. It is essential that strategies for treatment and containment be developed to avoid future epidemics of this magnitude. With the development of vaccines and antibody-based therapies using the envelope glycoprotein (GP of the 1976 Mayinga strain, one important strategy is to anticipate how the evolution of EBOV might compromise these efforts. In this study we have initiated a watch list of potential antibody escape mutations of EBOV by modeling interactions between GP and the antibody KZ52. The watch list was generated using molecular modeling to estimate stability changes due to mutation. Every possible mutation of GP was considered and the list was generated from those that are predicted to disrupt GP-KZ52 binding but not to disrupt the ability of GP to fold and to form trimers. The resulting watch list contains 34 mutations (one of which has already been seen in humans at six sites in the GP2 subunit. Should mutations from the watch list appear and spread during an epidemic, it warrants attention as these mutations may reflect an evolutionary response from the virus that could reduce the effectiveness of interventions such as vaccination. However, this watch list is incomplete and emphasizes the need for more experimental structures of EBOV interacting with antibodies in order to expand the watch list to other epitopes. We hope that this work provokes experimental research on evolutionary escape in both Ebola and other viral pathogens.

  13. Initiating a watch list for Ebola virus antibody escape mutations.

    Science.gov (United States)

    Miller, Craig R; Johnson, Erin L; Burke, Aran Z; Martin, Kyle P; Miura, Tanya A; Wichman, Holly A; Brown, Celeste J; Ytreberg, F Marty

    2016-01-01

    The 2014 Ebola virus (EBOV) outbreak in West Africa is the largest in recorded history and resulted in over 11,000 deaths. It is essential that strategies for treatment and containment be developed to avoid future epidemics of this magnitude. With the development of vaccines and antibody-based therapies using the envelope glycoprotein (GP) of the 1976 Mayinga strain, one important strategy is to anticipate how the evolution of EBOV might compromise these efforts. In this study we have initiated a watch list of potential antibody escape mutations of EBOV by modeling interactions between GP and the antibody KZ52. The watch list was generated using molecular modeling to estimate stability changes due to mutation. Every possible mutation of GP was considered and the list was generated from those that are predicted to disrupt GP-KZ52 binding but not to disrupt the ability of GP to fold and to form trimers. The resulting watch list contains 34 mutations (one of which has already been seen in humans) at six sites in the GP2 subunit. Should mutations from the watch list appear and spread during an epidemic, it warrants attention as these mutations may reflect an evolutionary response from the virus that could reduce the effectiveness of interventions such as vaccination. However, this watch list is incomplete and emphasizes the need for more experimental structures of EBOV interacting with antibodies in order to expand the watch list to other epitopes. We hope that this work provokes experimental research on evolutionary escape in both Ebola and other viral pathogens.

  14. Kinetics of Epstein-Barr Virus (EBV) Neutralizing and Virus-Specific Antibodies after Primary Infection with EBV

    Science.gov (United States)

    Bu, Wei; Hayes, Gregory M.; Liu, Hui; Gemmell, Lorraine; Schmeling, David O.; Radecki, Pierce; Aguilar, Fiona; Burbelo, Peter D.; Woo, Jennifer; Balfour, Henry H.

    2016-01-01

    Prospective studies of antibodies to multiple Epstein-Barr virus (EBV) proteins and EBV neutralizing antibodies in the same individuals before, during, and after primary EBV infection have not been reported. We studied antibody responses to EBV in college students who acquired primary EBV infection during prospective surveillance and correlated the kinetics of antibody response with the severity of disease. Neutralizing antibodies and enzyme-linked immunosorbent assay (ELISA) antibodies to gp350, the major target of neutralizing antibody, reached peak levels at medians of 179 and 333 days after the onset of symptoms of infectious mononucleosis, respectively. No clear correlation was found between the severity of the symptoms of infectious mononucleosis and the peak levels of antibody to individual viral proteins or to neutralizing antibody. In summary, we found that titers of neutralizing antibody and antibodies to multiple EBV proteins increase over many months after primary infection with EBV. PMID:26888186

  15. Proteasome Inhibition Suppresses Dengue Virus Egress in Antibody Dependent Infection.

    Directory of Open Access Journals (Sweden)

    Milly M Choy

    2015-11-01

    Full Text Available The mosquito-borne dengue virus (DENV is a cause of significant global health burden, with an estimated 390 million infections occurring annually. However, no licensed vaccine or specific antiviral treatment for dengue is available. DENV interacts with host cell factors to complete its life cycle although this virus-host interplay remains to be fully elucidated. Many studies have identified the ubiquitin proteasome pathway (UPP to be important for successful DENV production, but how the UPP contributes to DENV life cycle as host factors remains ill defined. We show here that proteasome inhibition decouples infectious virus production from viral RNA replication in antibody-dependent infection of THP-1 cells. Molecular and imaging analyses in β-lactone treated THP-1 cells suggest that proteasome function does not prevent virus assembly but rather DENV egress. Intriguingly, the licensed proteasome inhibitor, bortezomib, is able to inhibit DENV titers at low nanomolar drug concentrations for different strains of all four serotypes of DENV in primary monocytes. Furthermore, bortezomib treatment of DENV-infected mice inhibited the spread of DENV in the spleen as well as the overall pathological changes. Our findings suggest that preventing DENV egress through proteasome inhibition could be a suitable therapeutic strategy against dengue.

  16. Virus-neutralizing antibody response of mice to consecutive infection with human and avian influenza A viruses.

    Science.gov (United States)

    Janulíková, J; Stropkovská, A; Bobišová, Z; Košík, I; Mucha, V; Kostolanský, F; Varečková, E

    2015-06-01

    In this work we simulated in a mouse model a naturally occurring situation of humans, who overcame an infection with epidemic strains of influenza A, and were subsequently exposed to avian influenza A viruses (IAV). The antibody response to avian IAV in mice previously infected with human IAV was analyzed. We used two avian IAV (A/Duck/Czechoslovakia/1956 (H4N6) and the attenuated virus rA/Viet Nam/1203-2004 (H5N1)) as well as two human IAV isolates (virus A/Mississippi/1/1985 (H3N2) of medium virulence and A/Puerto Rico/8/1934 (H1N1) of high virulence). Two repeated doses of IAV of H4 or of H5 virus elicited virus-specific neutralizing antibodies in mice. Exposure of animals previously infected with human IAV (of H3 or H1 subtype) to IAV of H4 subtype led to the production of antibodies neutralizing H4 virus in a level comparable with the level of antibodies against the human IAV used for primary infection. In contrast, no measurable levels of virus-neutralizing (VN) antibodies specific to H5 virus were detected in mice infected with H5 virus following a previous infection with human IAV. In both cases the secondary infection with avian IAV led to a significant increase of the titer of VN antibodies specific to the corresponding human virus used for primary infection. Moreover, cross-reactive HA2-specific antibodies were also induced by sequential infection. By virtue of these results we suggest that the differences in the ability of avian IAV to induce specific antibodies inhibiting virus replication after previous infection of mice with human viruses can have an impact on the interspecies transmission and spread of avian IAV in the human population.

  17. Immune response to inactivated influenza virus vaccine: antibody reactivity with epidemic influenza B viruses of two highly distinct evolutionary lineages.

    Science.gov (United States)

    Pyhälä, R; Kleemola, M; Kumpulainen, V; Vartiainen, E; Lappi, S; Pönkä, A; Cantell, K

    1992-01-01

    Vaccination of adults (healthy female employees potentially capable of transmitting influenza to high-risk persons; n = 104) in autumn 1990 with a trivalent influenza virus vaccine containing B/Yamagata/16/88 induced a low antibody response to B/Finland/150/90, a recent variant of B/Victoria/2/87-like viruses, as compared with the antibody response to B/Finland/172/91, a current variant in the lineage of B/Yamagata/16/88-like viruses. Up to the end of the epidemic season, the antibody status declined but was still significantly better than before the vaccination. The results suggest that the vaccine strain was appropriate for the outbreak of 1990 to 1991 in Finland, but may provide unsatisfactory protection against B/Victoria/2/87-like viruses. Evidence is given that use of Madin-Darby canine kidney (MDCK)-grown virus as an antigen in the haemagglutination inhibition test (HI) may provide more reliable information about the protective antibodies than use of untreated or ether-treated egg-grown viruses. Significantly higher postvaccination and postepidemic antibody titres were recorded among subjects who exhibited the antibody before vaccination than among seronegative subjects. A significantly higher response rate among initially seronegative people than among seropositive people was recorded for antibody to B/Finland/150/90, but no clear evidence was obtained that the pre-existing antibody could have had a negative effect on the antibody production.

  18. A population screening test for antibody to measles virus

    International Nuclear Information System (INIS)

    Friedman, M.G.

    1981-01-01

    In areas where sporadic cases of measles continue to occur in spite of vaccination programs, the availability of a simple screening test for determination of seropositivity to measles virus is desirable. A sensitive radioimmunoassay (RIA) screening test (ST) for the detection of IgG antibody to measles virus, based on a solid phase RIA, is described. The assays were performed on polyvinyl microtiter plates for which the RIAST requires only 5 μl of serum per subject. Antigen consisted of a sonicated extract of measles virus-infected Vero cells. Rabbit antihuman IgG specific for the Fc-segment of human IgG, labelled with 125 I, was used to detect human IgG bound to viral antigen. The basic RIA method was characterized by carrying out full titrations of sera of 53 healthy adults, 10 children, and 13 patients with measles-associated illness. These sera were also tested by the hemagglutination inhibition (HI) technique; most of the measles sera were also tested by complement fixation (CF). RIAST results (expressed as binding ratios) obtained for 52 healthy adults are compared with their RIA serum titers. Of the 200 sera of patients of various ages tested by the RIAST, 63 borderline sera were also tested by HI. The RIAST, which does not require serum treatment other than inactivation, proved to be more sensitive as an indicator of seropositivity than HI. Implications of the results and practical applications of the screening test are discussed. (author)

  19. Development of human antibody fragments using antibody phage display for the detection and diagnosis of Venezuelan equine encephalitis virus (VEEV

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    Hust Michael

    2008-09-01

    Full Text Available Abstract Background Venezuelan equine encephalitis virus (VEEV belongs to the Alphavirus group. Several species of this family are also pathogenic to humans and are recognized as potential agents of biological warfare and terrorism. The objective of this work was the generation of recombinant antibodies for the detection of VEEV after a potential bioterrorism assault or an natural outbreak of VEEV. Results In this work, human anti-VEEV single chain Fragments variable (scFv were isolated for the first time from a human naïve antibody gene library using optimized selection processes. In total eleven different scFvs were identified and their immunological specificity was assessed. The specific detection of the VEEV strains TC83, H12/93 and 230 by the selected antibody fragments was proved. Active as well as formalin inactivated virus particles were recognized by the selected antibody fragments which could be also used for Western blot analysis of VEEV proteins and immunohistochemistry of VEEV infected cells. The anti-VEEV scFv phage clones did not show any cross-reactivity with Alphavirus species of the Western equine encephalitis virus (WEEV and Eastern equine encephalitis virus (EEEV antigenic complex, nor did they react with Chikungunya virus (CHIKV, if they were used as detection reagent. Conclusion For the first time, this study describes the selection of antibodies against a human pathogenic virus from a human naïve scFv antibody gene library using complete, active virus particles as antigen. The broad and sensitive applicability of scFv-presenting phage for the immunological detection and diagnosis of Alphavirus species was demonstrated. The selected antibody fragments will improve the fast identification of VEEV in case of a biological warfare or terroristic attack or a natural outbreak.

  20. Antibody responses against xenotropic murine leukemia virus-related virus envelope in a murine model.

    Directory of Open Access Journals (Sweden)

    Natalia Makarova

    2011-04-01

    Full Text Available Xenotropic murine leukemia virus-related virus (XMRV was recently discovered to be the first human gammaretrovirus that is associated with chronic fatigue syndrome and prostate cancer (PC. Although a mechanism for XMRV carcinogenesis is yet to be established, this virus belongs to the family of gammaretroviruses well known for their ability to induce cancer in the infected hosts. Since its original identification XMRV has been detected in several independent investigations; however, at this time significant controversy remains regarding reports of XMRV detection/prevalence in other cohorts and cell type/tissue distribution. The potential risk of human infection, coupled with the lack of knowledge about the basic biology of XMRV, warrants further research, including investigation of adaptive immune responses. To study immunogenicity in vivo, we vaccinated mice with a combination of recombinant vectors expressing codon-optimized sequences of XMRV gag and env genes and virus-like particles (VLP that had the size and morphology of live infectious XMRV.Immunization elicited Env-specific binding and neutralizing antibodies (NAb against XMRV in mice. The peak titers for ELISA-binding antibodies and NAb were 1:1024 and 1:464, respectively; however, high ELISA-binding and NAb titers were not sustained and persisted for less than three weeks after immunizations.Vaccine-induced XMRV Env antibody titers were transiently high, but their duration was short. The relatively rapid diminution in antibody levels may in part explain the differing prevalences reported for XMRV in various prostate cancer and chronic fatigue syndrome cohorts. The low level of immunogenicity observed in the present study may be characteristic of a natural XMRV infection in humans.

  1. Measles and canine distemper virus antibodies in patients with multiple sclerosis determined by radioimmunoassay

    International Nuclear Information System (INIS)

    Arnadottir, T.

    1980-01-01

    Antibodies against measles virus (MV) and canine distemper virus (CDV) were measured by solid-phase radioimmunoassay (RIA) of sera and cerebrospinal fluid (CSF) from 28 patients with multiple sclerosis (MS) and matched neurological controls. When the groups were compared for MV antibody titers and CDV antibody titers of sera and MV/CDV serum antibody titer ratios, no significant difference was found. The CDV antibody titers and the MV antibody titers were in good correlation. CDV antibodies showed RIA titration curves typical of low avidity antibodies. In tests for MV antibodies in CSF, 82% of the MS patients and 19% of the controls were positive, whereas 36% of the MS patients and 4% of the controls were positive in CDV RIA. The correlation between MV and CDV antibody levels, the low avidity of CDV antibodies and the fact that absorption of the specimens with MV antigen abolished all CDV antibody activity suggest that the CDV antibodies are MV antibodies cross-reacting with CDV. It is concluded that canine distemper virus is unlikely to be involved in the etiology of multiple sclerosis. (author)

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

    Directory of Open Access Journals (Sweden)

    Laura Evgin

    2016-01-01

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

  3. Structural basis for the antibody neutralization of Herpes simplex virus

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Cheng-Chung; Lin, Li-Ling [Academia Sinica, Taipei 115, Taiwan (China); Academia Sinica, Taipei 115, Taiwan (China); Chan, Woan-Eng [Development Center for Biotechnology, New Taipei City 221, Taiwan (China); Ko, Tzu-Ping [Academia Sinica, Taipei 115, Taiwan (China); Academia Sinica, Taipei 115, Taiwan (China); Lai, Jiann-Shiun [Development Center for Biotechnology, New Taipei City 221, Taiwan (China); Ministry of Economic Affairs, Taipei 100, Taiwan (China); Wang, Andrew H.-J., E-mail: ahjwang@gate.sinica.edu.tw [Academia Sinica, Taipei 115, Taiwan (China); Academia Sinica, Taipei 115, Taiwan (China); Taipei Medical University, Taipei 110, Taiwan (China)

    2013-10-01

    The gD–E317-Fab complex crystal revealed the conformational epitope of human mAb E317 on HSV gD, providing a molecular basis for understanding the viral neutralization mechanism. Glycoprotein D (gD) of Herpes simplex virus (HSV) binds to a host cell surface receptor, which is required to trigger membrane fusion for virion entry into the host cell. gD has become a validated anti-HSV target for therapeutic antibody development. The highly inhibitory human monoclonal antibody E317 (mAb E317) was previously raised against HSV gD for viral neutralization. To understand the structural basis of antibody neutralization, crystals of the gD ectodomain bound to the E317 Fab domain were obtained. The structure of the complex reveals that E317 interacts with gD mainly through the heavy chain, which covers a large area for epitope recognition on gD, with a flexible N-terminal and C-terminal conformation. The epitope core structure maps to the external surface of gD, corresponding to the binding sites of two receptors, herpesvirus entry mediator (HVEM) and nectin-1, which mediate HSV infection. E317 directly recognizes the gD–nectin-1 interface and occludes the HVEM contact site of gD to block its binding to either receptor. The binding of E317 to gD also prohibits the formation of the N-terminal hairpin of gD for HVEM recognition. The major E317-binding site on gD overlaps with either the nectin-1-binding residues or the neutralizing antigenic sites identified thus far (Tyr38, Asp215, Arg222 and Phe223). The epitopes of gD for E317 binding are highly conserved between two types of human herpesvirus (HSV-1 and HSV-2). This study enables the virus-neutralizing epitopes to be correlated with the receptor-binding regions. The results further strengthen the previously demonstrated therapeutic and diagnostic potential of the E317 antibody.

  4. Neutralizing antibody fails to impact the course of Ebola virus infection in monkeys.

    Directory of Open Access Journals (Sweden)

    Wendelien B Oswald

    2007-01-01

    Full Text Available Prophylaxis with high doses of neutralizing antibody typically offers protection against challenge with viruses producing acute infections. In this study, we have investigated the ability of the neutralizing human monoclonal antibody, KZ52, to protect against Ebola virus in rhesus macaques. This antibody was previously shown to fully protect guinea pigs from infection. Four rhesus macaques were given 50 mg/kg of neutralizing human monoclonal antibody KZ52 intravenously 1 d before challenge with 1,000 plaque-forming units of Ebola virus, followed by a second dose of 50 mg/kg antibody 4 d after challenge. A control animal was exposed to virus in the absence of antibody treatment. Passive transfer of the neutralizing human monoclonal antibody not only failed to protect macaques against challenge with Ebola virus but also had a minimal effect on the explosive viral replication following infection. We show that the inability of antibody to impact infection was not due to neutralization escape. It appears that Ebola virus has a mechanism of infection propagation in vivo in macaques that is uniquely insensitive even to high concentrations of neutralizing antibody.

  5. Vaccine induced antibodies to the first variable loop of human immunodeficiency virus type 1 gp120, mediate antibody-dependent virus inhibition in macaques.

    Science.gov (United States)

    Bialuk, Izabela; Whitney, Stephen; Andresen, Vibeke; Florese, Ruth H; Nacsa, Janos; Cecchinato, Valentina; Valeri, Valerio W; Heraud, Jean-Michel; Gordon, Shari; Parks, Robyn Washington; Montefiori, David C; Venzon, David; Demberg, Thorsten; Guroff, Marjorie Robert-; Landucci, Gary; Forthal, Donald N; Franchini, Genoveffa

    2011-12-09

    The role of antibodies directed against the hyper variable envelope region V1 of human immunodeficiency virus type 1 (HIV-1), has not been thoroughly studied. We show that a vaccine able to elicit strain-specific non-neutralizing antibodies to this region of gp120 is associated with control of highly pathogenic chimeric SHIV(89.6P) replication in rhesus macaques. The vaccinated animal that had the highest titers of antibodies to the amino terminus portion of V1, prior to challenge, had secondary antibody responses that mediated cell killing by antibody-dependent cellular cytotoxicity (ADCC), as early as 2 weeks after infection and inhibited viral replication by antibody-dependent cell-mediated virus inhibition (ADCVI), by 4 weeks after infection. There was a significant inverse correlation between virus level and binding antibody titers to the envelope protein, (R=-0.83, p=0.015), and ADCVI (R=-0.84 p=0.044). Genotyping of plasma virus demonstrated in vivo selection of three SHIV(89.6P) variants with changes in potential N-linked glycosylation sites in V1. We found a significant inverse correlation between virus levels and titers of antibodies that mediated ADCVI against all the identified V1 virus variants. A significant inverse correlation was also found between neutralizing antibody titers to SHIV(89.6) and virus levels (R=-0.72 p=0.0050). However, passive inoculation of purified immunoglobulin from animal M316, the macaque that best controlled virus, to a naïve macaque, resulted in a low serum neutralizing antibodies and low ADCVI activity that failed to protect from SHIV(89.6P) challenge. Collectively, while our data suggest that anti-envelope antibodies with neutralizing and non-neutralizing Fc(R-dependent activities may be important in the control of SHIV replication, they also demonstrate that low levels of these antibodies alone are not sufficient to protect from infection. Published by Elsevier Ltd.

  6. Separation of hemagglutination-inhibiting immunoglobulin M antibody to rubella virus in human serum by high-performance liquid chromatography.

    OpenAIRE

    Kobayashi, N; Suzuki, M; Nakagawa, T; Matumoto, M

    1986-01-01

    High-performance liquid chromatography was successfully used to separate hemagglutination-inhibiting immunoglobulin M (IgM) rubella virus antibody from IgG rubella virus antibody in human serum. The fractionation by high-performance liquid chromatography was as effective as sucrose density gradient centrifugation in separating IgM antibody from IgG antibody.

  7. INFECTIOUS VIRUS-ANTIBODY COMPLEX IN THE BLOOD OF CHRONICALLY INFECTED MICE

    Science.gov (United States)

    Notkins, Abner Louis; Mahar, Suellen; Scheele, Christina; Goffman, Joel

    1966-01-01

    If viremic sera from mice chronically infected with lactic dehydrogenase virus (LDV) were first treated with ether or ultraviolet light to inactivate the infectious virus, neutralizing antibody could be demonstrated. Significant amounts of antibody, however, were not detected until the mice had been infected for about 2½ months and its presence did not result in the elimination of the chronic viremia. Virus isolated from sera containing neutralizing antibody was found to be relatively resistant to neutralization by anti-LDV. Further studies revealed that the resistant virus existed in the form of an infectious virus-antibody complex (sensitized virus). The presence of such a complex was demonstrated by the fact that the virus fraction which persisted after in vivo or in vitro exposure to mouse anti-LDV was readily neutralized by goat anti-mouse sera or goat anti-mouse γ-globulin, whereas virus that had not been previously exposed to mouse anti-LDV was completely resistant to neutralization by goat anti-mouse sera. These findings suggest that (a) sensitization may play an important role in the resistance and susceptibility of a virus to neutralization by antiviral antibody, and (b) an anti-γ-globulin may prove useful in neutralizing the resistant fraction and in demonstrating otherwise undetectable antiviral antibody. PMID:5944351

  8. Persistence of Antibodies to West Nile Virus in Naturally Infected Rock Pigeons (Columba livia)

    Science.gov (United States)

    Gibbs, Samantha E. J.; Hoffman, Douglas M.; Stark, Lillian M.; Marlenee, Nicole L.; Blitvich, Bradley J.; Beaty, Barry J.; Stallknecht, David E.

    2005-01-01

    Wild caught rock pigeons (Columba livia) with antibodies to West Nile virus were monitored for 15 months to determine antibody persistence and compare results of three serologic techniques. Antibodies persisted for the entire study as detected by epitope-blocking enzyme-linked immunosorbent assay and plaque reduction neutralization test. Maternal antibodies in squabs derived from seropositive birds persisted for an average of 27 days. PMID:15879030

  9. Prevalence of Antibodies Against Hepatitis e Virus in Veterinarians in Estonia

    DEFF Research Database (Denmark)

    Lassen, Brian; Janson, Marilin; Neare, Kädi

    2017-01-01

    positive with both tests. Antibody-positive samples were further examined for the presence of HEV RNA. Three (2.6%) of the 115 veterinarians tested positive for immunoglobulin G antibodies against HEV, whereas no immunoglobulin M antibodies against the virus were detected. The antibody......-positive veterinarians were small animal practitioners. Pigs comprised no or small part of their working time or patients. No HEV RNA was detected in the antibody-positive samples. The prevalence of antibodies against HEV in veterinarians in Estonia was lower than what has been observed in veterinarians in other...

  10. Anti-JC virus antibody prevalence in a multinational multiple sclerosis cohort

    DEFF Research Database (Denmark)

    Olsson, Tomas; Achiron, Anat; Alfredsson, Lars

    2013-01-01

    JC virus (JCV) is an opportunistic virus known to cause progressive multifocal leukoencephalopathy. Anti-JC virus (Anti-JCV) antibody prevalence in a large, geographically diverse, multi-national multiple sclerosis (MS) cohort was compared in a cross-sectional study. Overall, anti-JCV antibody...... prevalence was 57.6%. Anti-JCV antibody prevalence in MS patients ranged from approximately 47% to 68% across these countries: Norway, 47.4%; Denmark, 52.6%; Israel, 56.6%; France, 57.6%; Italy, 58.3%; Sweden, 59.0%; Germany, 59.1%; Austria, 66.7% and Turkey, 67.7%. Prevalence increased with age (from 49...

  11. Rapid Identification of Dengue Virus Serotypes Using Monoclonal Antibodies in an Indirect Immunofluorescence Test.

    Science.gov (United States)

    1982-06-18

    encephalitis(TBH-28), West Nile(E-101), Yellow fever(French neurotropic and 17D strains), and Zika . Two Sandfly Fever viruses (213452 and Candiru) were...were provided as first passage isolates ( Aedes pseudoscutellaris cells, AP-61) or human serum from recent dengue virus patients. African isolates... viruses of the Phlebovirus genus (Table 1). Several monoclonal antibody preparations reacted solely with dengue virus serotypes. Two preparations (13E7 and

  12. CANINE DISTEMPER VIRUS ANTIBODY TITERS IN DOMESTIC CATS AFTER DELIVERY OF A LIVE ATTENUATED VIRUS VACCINE.

    Science.gov (United States)

    Ramsay, Edward; Sadler, Ryan; Rush, Robert; Seimon, Tracie; Tomaszewicz, Ania; Fleetwood, Ellen A; McAloose, Denise; Wilkes, Rebecca P

    2016-06-01

    Three methods for delivering a live attenuated canine distemper virus (CDV) vaccine to domestic cats ( Felis catus ) were investigated, as models for developing vaccination protocols for tigers (Panthera tigris). Twenty domestic cats were randomly divided into four treatment groups: saline injection (negative controls); and oral, intranasal, and subcutaneous vaccinates. Cats were injected with saline or a CDV vaccine (Nobivac DP, Merck) at wk 0 and 4. Blood and nasal swabs were collected at wk 0 (prior to the initial vaccination) and weekly thereafter for 9 wk. Urine samples were collected on wk 1 to 9 after initial vaccination. Forty-nine weeks following the initial vaccination series, three cats from the subcutaneous group and three cats from the intranasal group were revaccinated. Blood was collected immediately prior, and 7 and 21 days subsequent to revaccination. Nasal swabs and urine samples were collected from each cat prior to wk 49 revaccination and daily for 7 days thereafter. Nasal swabs and urine were analyzed by quantitative PCR for vaccine virus presence. Sera were tested for CDV antibodies by virus neutralization. All cats were sero-negative for CDV antibodies at the beginning of the study, and saline-injected cats remained sero-negative throughout the study. A dramatic anamnestic response was seen following wk 4 subcutaneous vaccinations, with titers peaking at wk 6 (geometric mean = 2,435.5). Following wk 49 revaccination, subcutaneous vaccinates again mounted impressive titers (wk 52 geometric mean = 2,048). Revaccination of the intranasal group cats at wk 49 produced a small increase in titers (wk 52 geometric mean = 203). CDV viral RNA was detected in six nasal swabs but no urine samples, demonstrating low viral shedding postvaccination. The strong antibody response to subcutaneous vaccination and the lack of adverse effects suggest this vaccine is safe and potentially protective against CDV infection in domestic cats.

  13. Seasonal variation of maternally derived respiratory syncytial virus antibodies and association with infant hospitalizations for respiratory syncytial virus

    DEFF Research Database (Denmark)

    Stensballe, Lone Graff; Ravn, Henrik; Kristensen, Kim

    2009-01-01

    This study used 459 prospectively sampled cord blood samples to examine the association between maternally derived respiratory syncytial virus (RSV)-neutralizing antibodies and the RSV hospitalization season in Denmark. We found a clear temporal association and suggest that RSV-neutralizing antib......This study used 459 prospectively sampled cord blood samples to examine the association between maternally derived respiratory syncytial virus (RSV)-neutralizing antibodies and the RSV hospitalization season in Denmark. We found a clear temporal association and suggest that RSV......-neutralizing antibody level plays a role in the RSV seasonal pattern....

  14. Comparisons of Venezuelan encephalitis virus strains by hemagglutination-inhibition tests with chicken antibodies.

    Science.gov (United States)

    Scherer, W F; Pancake, B A

    1977-01-01

    Twenty strains of Venezuelan encephalitis (VE) virus inoculated intravenously in large doses into roosters produced hemagglutination-inhibition (HI) antibodies detectable in plasmas within 7 to 10 days. No signs of illness occurred, and there was no evidence of viral growth in tissues since blood concentrations of infectious virus steadily decreased after inoculation. HI antibodies in early plasmas were specific for VE virus and did not cross-react significantly with two other North American alphaviruses, eastern and western encephalitis viruses. VE virus strains could be distinquished by virus-dilution, short-incubation HI, but not by plasma-dilution neutralization tests, by using early rooster antibodies. The distinctions by HI test were similar with some strains to, but different with other strains from, those described by Young and Johnson with the spiny rat antisera used to establish their subtype classifications of VE virus (14, 28). Nevertheless, results of HI tests with rooster antibodies correlated with equine virulence, as did results with spiny rat antibodies, and distinguished the new strains of virus that appeared in Middle America during the VE outbreak of 1969 from preexisting strains. PMID:591629

  15. Bovine respiratory syncytial virus ISCOMs - protection in the presence of maternal antibodies

    DEFF Research Database (Denmark)

    Hägglund, Sara; Hu, Ke-Fei; Larsen, Lars Erik

    2004-01-01

    The protection induced by immunostimulating complexes (ISCOMs) against bovine respiratory syncytial virus (BRSV) was evaluated and compared to that of a commercial inactivated vaccine (CV) in calves with BRSV-specific maternal antibodies. Following experimental challenge, controls (n = 4...

  16. Limited interlaboratory comparison of Schmallenberg virus antibody detection in serum samples

    DEFF Research Database (Denmark)

    van der Poel, W. H. M.; Cay, B.; Zientara, S.

    2014-01-01

    Eight veterinary institutes in seven different countries in Europe participated in a limited interlaboratory comparison trial to evaluate laboratory performances of Schmallenberg virus (SBV) antibody detection in serum. Seven different sheep sera and three different cattle sera were circulated, a...

  17. Detection systems for antibody responses against herpes B virus

    OpenAIRE

    Pöhlmann, Stefan; Krüger, Astrid; Hafezi, Wali; Schneider, Stefan; Gruber, Jens; Winkler, Michael; Kaul, Artur

    2017-01-01

    Herpes B virus (BV) infection is highly prevalent among adult Asian macaques and rarely causes severe disease in infected animals. In contrast, BV infection of humans can induce fatal encephalitis in the absence of treatment. Therefore, the development of diagnostic tests for specific and sensitive detection of antibodies against BV is an important task. The cross-reactivity of antibodies against BV with related simplex viruses of other primates may afford an opportunity to ...

  18. The cellular bases of antibody responses during dengue virus infection

    Directory of Open Access Journals (Sweden)

    Juan Carlos Yam-Puc

    2016-06-01

    Full Text Available Dengue virus (DENV is one of the most significant human viral pathogens transmitted by mosquitoes and can cause from an asymptomatic disease to mild undifferentiated fever, classical dengue, and severe dengue. Neutralizing memory antibody (Ab responses are one of the most important mechanisms that counteract reinfections and are therefore the main aim of vaccination. However, it has also been proposed that in dengue, some of these class-switched (IgG memory Abs might worsen the disease. Although these memory Abs derive from B cells by T-cell dependent processes, we know rather little about the (acute, chronic or memory B cell responses and the complex cellular mechanisms generating these Abs during DENV infections.This review aims to provide an updated and comprehensive perspective of the B cell responses during DENV infection, starting since the very early events like the cutaneous DENV entrance and the arrival into draining lymph nodes, to the putative B cell activation, proliferation and germinal centers (GCs formation (the source of affinity-matured class-switched memory Abs, till the outcome of GC reactions such as the generation of plasmablasts, Ab-secreting plasma cells and memory B cells. We discuss topics very poorly explored such as the possibility of B cell infection by DENV or even activation-induced B cell death. The current information about the nature of the Ab responses to DENV is also illustrated.

  19. Prevalence and titers of yellow fever virus neutralizing antibodies in previously vaccinated adults.

    Science.gov (United States)

    Miyaji, Karina Takesaki; Avelino-Silva, Vivian Iida; Simões, Marisol; Freire, Marcos da Silva; Medeiros, Carlos Roberto de; Braga, Patrícia Emilia; Neves, Maria Angélica Acalá; Lopes, Marta Heloisa; Kallas, Esper Georges; Sartori, Ana Marli Christovam

    2017-04-03

    The World Health Organization (WHO) recommends one single dose of the Yellow Fever (YF) vaccine based on studies of antibody persistency in healthy adults. We assessed the prevalence and titers of YF virus neutralizing antibodies in previously vaccinated persons aged  60 years, in comparison to younger adults. We also evaluated the correlation between antibody titers and the time since vaccination among participants who received one vaccine dose, and the seropositivity among participants vaccinated prior to or within the past 10 years. previously vaccinated healthy persons aged  18 years were included. YF virus neutralizing antibody titers were determined by means of the 50% Plaque Reduction Neutralization Test. 46 persons aged  60 years and 48 persons aged 18 to 59 years were enrolled. There was no significant difference in the prevalence of YF virus neutralizing antibodies between the two groups (p = 0.263). However, titers were significantly lower in the elderly (p = 0.022). There was no correlation between YF virus neutralizing antibody titers and the time since vaccination. There was no significant difference in seropositivity among participants vaccinated prior to or within the past 10 years. the clinical relevance of the observed difference in YF virus neutralizing antibody titers between the two groups is not clear.

  20. Canine distemper virus DNA vaccination of mink can overcome interference by maternal antibodies

    DEFF Research Database (Denmark)

    Jensen, Trine Hammer; Nielsen, Line; Aasted, Bent

    2015-01-01

    Canine distemper virus (CDV) is highly contagious and can cause severe disease against which conventional live vaccines are ineffective in the presence of maternal antibodies. Vaccination in the presences of maternal antibodies was challenged by vaccination of 5 days old and 3 weeks old mink kits...

  1. Antibodies to the human T-cell lymphoma/leukemia virus type I in Dutch haemophiliacs

    NARCIS (Netherlands)

    Goudsmit, J.; Miedema, F.; Breederveld, C.; Terpstra, F.; Roos, M.; Schellekens, P.; Melief, C.

    1986-01-01

    95 Dutch haemophiliacs were tested for antibodies to membrane antigens on cells infected with human T-cell leukemia virus type I (HTLV-I-MA) by indirect immunofluorescence and to purified HTLV-I by enzyme-linked immunosorbent assay. Antibodies to HTLV-I-MA were present in 8 of 95 (8%) haemophiliacs,

  2. Hepatitis c virus antibodies in mother-infant blood pair in Zaria

    African Journals Online (AJOL)

    2017-06-01

    Jun 1, 2017 ... Abstract: Objectives: To deter- mine the prevalence of Hepatitis. C virus (HCV) antibodies in mother-infant pair, and risk fac- tors for vertical transmission of. HCV in ABUTH Zaria. Method: One hundred mother- infant pair had serological deter- mination for HCV antibodies from birth to 28days and a repeat.

  3. Homology of ab1 and ab3 monoclonal antibodies that neutralize Semliki Forest virus

    NARCIS (Netherlands)

    Fernandez, IM; Bos, NA; Harmsen, M; Verheul, AFM; Snippe, H; Kraaijeveld, CA

    2001-01-01

    A noninternal image monoclonal antiidiotypic antibody (ab2 mAb), designated 1,13A321, that had proved its efficacy as vaccine against infection with Semliki Forest virus (SFV) in BALB/c mice, was used as immunogen to generate a panel of SFV-neutralizing monoclonal anti-anti-idiotypic antibodies (ab3

  4. Pan-ebolavirus and Pan-filovirus Mouse Monoclonal Antibodies: Protection against Ebola and Sudan Viruses.

    Science.gov (United States)

    Holtsberg, Frederick W; Shulenin, Sergey; Vu, Hong; Howell, Katie A; Patel, Sonal J; Gunn, Bronwyn; Karim, Marcus; Lai, Jonathan R; Frei, Julia C; Nyakatura, Elisabeth K; Zeitlin, Larry; Douglas, Robin; Fusco, Marnie L; Froude, Jeffrey W; Saphire, Erica Ollmann; Herbert, Andrew S; Wirchnianski, Ariel S; Lear-Rooney, Calli M; Alter, Galit; Dye, John M; Glass, Pamela J; Warfield, Kelly L; Aman, M Javad

    2016-01-01

    The unprecedented 2014-2015 Ebola virus disease (EVD) outbreak in West Africa has highlighted the need for effective therapeutics against filoviruses. Monoclonal antibody (MAb) cocktails have shown great potential as EVD therapeutics; however, the existing protective MAbs are virus species specific. Here we report the development of pan-ebolavirus and pan-filovirus antibodies generated by repeated immunization of mice with filovirus glycoproteins engineered to drive the B cell responses toward conserved epitopes. Multiple pan-ebolavirus antibodies were identified that react to the Ebola, Sudan, Bundibugyo, and Reston viruses. A pan-filovirus antibody that was reactive to the receptor binding regions of all filovirus glycoproteins was also identified. Significant postexposure efficacy of several MAbs, including a novel antibody cocktail, was demonstrated. For the first time, we report cross-neutralization and in vivo protection against two highly divergent filovirus species, i.e., Ebola virus and Sudan virus, with a single antibody. Competition studies indicate that this antibody targets a previously unrecognized conserved neutralizing epitope that involves the glycan cap. Mechanistic studies indicated that, besides neutralization, innate immune cell effector functions may play a role in the antiviral activity of the antibodies. Our findings further suggest critical novel epitopes that can be utilized to design effective cocktails for broad protection against multiple filovirus species. Filoviruses represent a major public health threat in Africa and an emerging global concern. Largely driven by the U.S. biodefense funding programs and reinforced by the 2014 outbreaks, current immunotherapeutics are primarily focused on a single filovirus species called Ebola virus (EBOV) (formerly Zaire Ebola virus). However, other filoviruses including Sudan, Bundibugyo, and Marburg viruses have caused human outbreaks with mortality rates as high as 90%. Thus, cross

  5. Enhanced sensitivity in detection of antiviral antibody responses using biotinylation of foot-and-mouth disease virus (FMDV) capsids

    Science.gov (United States)

    Analysis of the immune response to infection of livestock by foot-and-mouth disease virus (FMDV) is most often reported as the serum antibody response to the virus. While measurement of neutralizing antibody has been sensitive and specific, measurements of the quality of the antibody response are le...

  6. Radioimmunoassay for detection of VP1 specific neutralizing antibodies of foot and mouse disease virus

    International Nuclear Information System (INIS)

    Patzer, E.J.; Jackson, M.L.; Moore, D.M.

    1985-01-01

    A solid-phase radioimmunoassay was developed for the detection of antibodies against a specific region of the VP1 protein of the A24 and O1 serotypes of foot and mouth disease virus. The antibody titers from the radioimmunoassay showed a positive correlation with neutralizing antibody titers determined by a mouse protection assay. The specificity of the assay resides in the peptide used as antigen. The assay is rapid, reproducible and does not require the use of whole virions. (orig.)

  7. Single-Domain Antibodies as Tools to Perturb and Study RNA Viruses

    NARCIS (Netherlands)

    Hanke, Leo

    2017-01-01

    In this thesis, I describe the generation and characterization of alpaca-derived, antiviral, single-domain antibody fragments (VHHs). The antiviral targets of the described VHHs are the nuclear proteins of influenza A virus (IAV) and vesicular stomatitis virus (VSV). The described VHHs protect cells

  8. Association between psychopathic disorder and serum antibody to herpes simplex virus (type 1).

    Science.gov (United States)

    Cleobury, J F; Skinner, G R; Thouless, M E; Wildy, P

    1971-02-20

    The sera of a small of patients has been examined for herpes simplex virus antibody. Three clinically-defined groups of patients were compared: (a) aggressive psychopaths, (b) psychiatric controls, and (c) general hospital patients. The first group had an unusually high average kinetic neutralization constant against type 1 herpes simplex virus.

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

    Science.gov (United States)

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

    2013-01-01

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

  10. Sensitive radioimmunoassay for the determination of antibodies to mouse hepatitis virus

    Energy Technology Data Exchange (ETDEWEB)

    Leibowitz, J L [California Univ., San Diego, La Jolla (USA); Fung, L S; Levy, G A [Toronto Univ., Ontario (Canada)

    1983-05-01

    A solid-phase radioimmunoassay is described for the detection of antibodies to mouse hepatitis virus. Viruses were purified by velocity and isopycnic gradient centrifugation and 96-well plastic plates were coated with viral antigens. To allow the detection of most serotypes of low titered antisera, a pool of antigens from several viral serotypes were employed. The second antibody, an affinity-purified goat antimouse immunoglobulin, detects IgG, IgM and IgA antibodies. This assay is more sensitive than either the plaque reduction assay or the commercially available enzyme-linked immunosorbant assay and proved to be useful for screening mouse colonies for the presence of mouse hepatitis virus, following seroconversion in experimental animals and in the production of monoclonal antibodies to both structural and nonstructural proteins.

  11. A sensitive radioimmunoassay for the determination of antibodies to mouse hepatitis virus

    International Nuclear Information System (INIS)

    Leibowitz, J.L.; Fung, L.S.; Levy, G.A.

    1983-01-01

    A solid-phase radioimmunoassay is described for the detection of antibodies to mouse hepatitis virus. Viruses were purified by velocity and isopycnic gradient centrifugation and 96-well plastic plates were coated with viral antigens. To allow the detection of most serotypes of low titered antisera, a pool of antigens from several viral serotypes were employed. The second antibody, an affinity-purified goat antimouse immunoglobulin, detects IgG, IgM and IgA antibodies. This assay is more sensitive than either the plaque reduction assay or the commercially available enzyme-linked immunosorbant assay and proved to be useful for screening mouse colonies for the presence of mouse hepatitis virus, following seroconversion in experimental animals and in the production of monoclonal antibodies to both structural and nonstructural proteins. (Auth.)

  12. An influenza A virus agglutination test using antibody-like polymers.

    Science.gov (United States)

    Sukjee, Wannisa; Thitithanyanont, Arunee; Wiboon-Ut, Suwimon; Lieberzeit, Peter A; Paul Gleeson, M; Navakul, Krongkaew; Sangma, Chak

    2017-10-01

    Antibodies are commonly used in diagnostic routines to identify pathogens. The testing protocols are relatively simple, requiring a certain amount of a specific antibody to detect its corresponding pathogen. Antibody functionality can be mimicked by synthesizing molecularly imprinted polymers (MIPs), i.e. polymers that can selectively recognize a given template structure. Thus, MIPs are sometimes termed 'plastic antibody (PA)'. In this study, we have synthesized new granular MIPs using influenza A virus templates by precipitation polymerization. The selective binding of influenza A to the MIP particles was assessed and subsequently contrasted with other viruses. The affinities of influenza A virus towards the MIP was estimated based on an agglutination test by measuring the amount of influenza subtypes absorbed onto the MIPs. The MIPs produced using the H1N1 template showed specific reactivity to H1N1 while those produced using H5N1 and H3N2 templates showed cross-reactivity.

  13. A comparison of labelled antibody methods for the detection of virus antigens in cell monolayers

    International Nuclear Information System (INIS)

    Oram, J.D.; Crooks, A.J.

    1979-01-01

    A number of labelled antibody methods have been applied to the detection of Semliki Forest virus antigens after replication of the virus in monolayers of host cells in multi-well polystyrene plates. The importance of several reaction variables has been investigated and the sensitivity of the methods compared for different periods of virus replication. Direct assays with radio-labelled antibody (RLA) and indirect assays peroxidase-antiperoxidase complexes (PAP) were equally sensitive. Direct and indirect assays using enzyme-linked antibodies (ELA) were slightly less sensitive than the direct RLA and PAP methods but were more sensitive than the indirect RLA or fluorescent antibody (FLA) methods. Direct assays using ELA were more rapid and easier to perform than the other assay methods. (Auth.)

  14. Optimization of a method for the detection of immunopotentiating antibodies against serotype 1 of dengue virus

    International Nuclear Information System (INIS)

    Soto Garita, Claudio

    2014-01-01

    An immunopotentiation trial has used sera from dengue seropositive patients from Costa Rica's endemic areas. The detection and semi-quantification of immunopotentiating antibodies were optimized against dengue virus serotype 1. The cell line K562 (human erythromyeloblastoid leukemia cells) has been more efficient than the U937 (human histiocytic lymphoma cells). A more adequate detection of immunopotentiating antibodies was determined. The optimal infection and virus-antibody incubation parameters are demonstrated for the detection of immunopotentiating antibodies with the immunostaining technique. The immuno-optimized assay has allowed the detection and semi-quantification of immunopotentiating antibodies against serotype 1 of dengue virus. Samples of strong positive, weak positive and dengue negative sera are analyzed. The end has been to evaluate the usefulness in the detection and semi-quantification of immunopotentiating antibodies. The presence of immunopotentiating antibodies was demonstrated against dengue virus serotype 1 in endemic zones of Costa Rica, to complement with the evaluation of the other existing serotypes is recommended [es

  15. Co-evolution of a broadly neutralizing HIV-1 antibody and founder virus

    Science.gov (United States)

    Liao, Hua-Xin; Lynch, Rebecca; Zhou, Tongqing; Gao, Feng; Alam, S. Munir; Boyd, Scott D.; Fire, Andrew Z.; Roskin, Krishna M.; Schramm, Chaim A.; Zhang, Zhenhai; Zhu, Jiang; Shapiro, Lawrence; Mullikin, James C.; Gnanakaran, S.; Hraber, Peter; Wiehe, Kevin; Kelsoe, Garnett; Yang, Guang; Xia, Shi-Mao; Montefiori, David C.; Parks, Robert; Lloyd, Krissey E.; Scearce, Richard M.; Soderberg, Kelly A.; Cohen, Myron; Kaminga, Gift; Louder, Mark K.; Tran, Lillan M.; Chen, Yue; Cai, Fangping; Chen, Sheri; Moquin, Stephanie; Du, Xiulian; Joyce, Gordon M.; Srivatsan, Sanjay; Zhang, Baoshan; Zheng, Anqi; Shaw, George M.; Hahn, Beatrice H.; Kepler, Thomas B.; Korber, Bette T.M.; Kwong, Peter D.; Mascola, John R.; Haynes, Barton F.

    2013-01-01

    Current HIV-1 vaccines elicit strain-specific neutralizing antibodies. However, cross-reactive neutralizing antibodies arise in ~20% of HIV-1-infected individuals, and details of their generation could provide a roadmap for effective vaccination. Here we report the isolation, evolution and structure of a broadly neutralizing antibody from an African donor followed from time of infection. The mature antibody, CH103, neutralized ~55% of HIV-1 isolates, and its co-crystal structure with gp120 revealed a novel loop-based mechanism of CD4-binding site recognition. Virus and antibody gene sequencing revealed concomitant virus evolution and antibody maturation. Notably, the CH103-lineage unmutated common ancestor avidly bound the transmitted/founder HIV-1 envelope glycoprotein, and evolution of antibody neutralization breadth was preceded by extensive viral diversification in and near the CH103 epitope. These data elucidate the viral and antibody evolution leading to induction of a lineage of HIV-1 broadly neutralizing antibodies and provide insights into strategies to elicit similar antibodies via vaccination. PMID:23552890

  16. Prevalence Estimates of Antibodies Towards Foot-and-Mouth Disease Virus in Small Ruminants in Uganda

    DEFF Research Database (Denmark)

    Balinda, Sheila Nina; Tjørnehøj, Kirsten; Muwanika, Vincent B.

    2009-01-01

    summarizes results of serological investigations of sheep and goats for antibodies to FMDV from four districts in 2006 following an FMD outbreak in the region and from an attempted comprehensive random sampling in two districts in 2007. Antibodies were quantified and serotyped using competitive ELISA...... for antibodies towards non-structural proteins (NSP) and structural proteins towards serotype O, and blocking ELISA for antibodies towards the seven serotypes of FMD virus (FMDV). In 2006, sheep and goats in Bushenyi and Isingiro districts were free from antibodies towards FMDV, while herds in Kasese and Mbarara...... districts excluding Kahendero village were all positive for antibodies towards NSP and SP-O. In 2007, mean prevalence estimates of antibodies towards FMDV NSP was 14% in goats and 22% in sheep in Kasese district, while Bushenyi was still free. The difference between these two districts probably reflects...

  17. [IgM class antibodies against hepatitis A viruses in the differentiation of viral hepatitis].

    Science.gov (United States)

    Zivanović-Marinković, V; Stanković, D; Parabucki, S; Lazarov, A; Marinković, V; Krstić, L; Letica, Z

    1982-01-01

    The sera of 64 patients with acute viral hepatitis which were previously HbsAG negative by rPHA were tested by RIA methods for the presence of HBsAG and anti-HBc, by EIA method for HBc and anti-HBc and also by RIA method for the presence of IgM antibodies against hepatitis A virus. The pairs of sera were tested also for the presence of antibodies against cytomegalovirus and EB viruses. Of the total of 64 patients, markers of fresh HB viral infection were proved in 5 patients, sera positive to IgM antibodies to hepatitis A virus were found in 51 and no positive tests to any of the tested viruses were found in 8. The authors consider that they belonged to "non-A, non-B" viral hepatitis.

  18. A liquid phase blocking ELISA for the detection of antibodies against infectious bronchitis virus

    Directory of Open Access Journals (Sweden)

    Cardoso T.C.

    1999-01-01

    Full Text Available A liquid phase blocking ELISA (LPB-ELISA was developed for the detection and measurement of antibodies against infectious bronchitis virus (IBV. The purified and nonpurified virus used as antigen, the capture and detector antibodies, and the chicken hyperimmune sera were prepared and standardized for this purpose. A total of 156 sera from vaccinated and 100 from specific pathogen-free chickens with no recorded contact with the virus were tested. The respective serum titers obtained in the serum neutralization test (SNT were compared with those obtained in the LPB-ELISA. There was a high correlation (r2 = 0.8926 between the two tests. The LPB-ELISA represents a single test suitable for the rapid detection of antibodies against bronchitis virus in chicken sera, with good sensitivity (88%, specificity (100% and agreement (95.31%.

  19. Subtype-Specific Influenza A Virus Antibodies in Canada Geese (Branta canadensis)

    Science.gov (United States)

    Kistler, Whitney M.; Stallknecht, David E.; DeLiberto, Thomas J.; Van Why, Kyle; Yabsley, Michael J.

    2015-01-01

    Historically, surveillance for influenza A viruses (IAVs) in wild birds has relied on viral detection assays. This was largely due to poor performance of serological assays in wild birds; however, recently developed commercial serological assays have improved the ability to detect IAV antibodies in wild birds. Serological surveillance for IAV antibodies in Canada geese (Branta canadensis) has shown that, despite a low prevalence of virus isolations, Canada geese are frequently exposed to IAVs and that exposure increases with latitude, which follows virus isolation prevalence patterns observed in dabbling ducks. The objectives of this study were to further evaluate IAV antibodies in Canada geese using a subtype-specific serological assay to determine if Canada geese are exposed to subtypes that commonly circulate in dabbling ducks. We collected serum samples from Canada geese in Minnesota, New Jersey, Pennsylvania, and Wisconsin and tested for antibodies to IAVs using a blocking ELISA. Positive samples were further tested by hemagglutination inhibition for 10 hemagglutinin IAV subtypes (H1–H10). Overall, we detected antibodies to NP in 24% (714/2,919) of geese. Antibodies to H3, H4, H5, and H6 subtypes predominated, with H5 being detected most frequently. A decrease in H5 HI antibody prevalence and titers was observed from 2009 to 2012. We also detected similar exposure pattern in Canada geese from New Jersey, Minnesota, Washington and Wisconsin. Based on the published literature, H3, H4, and H6 viruses are the most commonly reported IAVs from dabbling ducks. These results indicate that Canada geese also are frequently exposed to viruses of the same HA subtypes; however, the high prevalence of antibodies to H5 viruses was not expected as H5 IAVs are generally not well represented in reported isolates from ducks. PMID:25845755

  20. The use of monoclonal antibodies in competitive ELISA for the detection of antibodies to rinderpest and peste des petits ruminants viruses

    International Nuclear Information System (INIS)

    Anderson, J.; McKay, J.A.; Butcher, R.N.

    1991-01-01

    A monoclonal antibody against the haemagglutinin of rinderpest virus has been used in a competitive ELISA (C-ELISA) for the detection of antibodies to rinderpest virus in cattle, sheep, goat and game sera. Unlike the indirect ELISA and the virus neutralisation test (VNT), the C-ELISA detects only antibodies to rinderpest virus and gives no cross-reactivity with antibodies to peste des petits ruminants (PPR) virus. Antibodies to a wide range of strains of rinderpest virus have been detected using this assay, suggesting its suitability for both sero-monitoring and sero-surveillance. Analysis of C-ELISA results from the examination of field sera shows a much greater separation of negative and positive populations as compared to the indirect ELISA. A further monoclonal antibody against the H protein of PPR has also been found suitable for use in a C-ELISA for the detection of antibodies to PPR virus. The use of these two C-ELISA's has made possible rapid differential sero-diagnosis without recourse to cross-VNT testing. The use of monoclonal antibody-based assays will allow much greater standardisation of rinderpest and PPR diagnosis, and following field-trials the C-ELISA will replace the indirect ELISA for sero-monitoring throughout the Pan African Rinderpest Campaign. (author). 3 refs, 6 figs, 1 tab

  1. A monoclonal antibody to inclusion body disease of cranes virus enabling specific immunohistochemistry and competitive ELISA

    Science.gov (United States)

    Letchworth, G.J.; Fishel, J.R.; Hansen, W.R.

    1997-01-01

    Inclusion body disease of cranes (IBDC) herpesvirus kills some infected cranes and persists in convalescent animals. To enable further study and rapid identification of carrier animals, we developed a monoclonal antibody (MAb) to IBDC virus and used it in immunohistochemistry and a competitive enzyme-linked immunosorbent assay (ELISA). We used conventional techniques to make murine MAbs directed against IBDC virus purified from infected duck embryo cells. Hybridomas reacting in an ELISA with IBDC virus but not uninfected duck embryo cells were characterized by radioimmunoprecipitation, in situ immunohistochemistry, and competitive ELISA with neutralizing and nonneutralizing crane sera. MAb 2C11 immunoprecipitated 59-, 61-, and 110-kD proteins from IBDC virus-infected but not uninfected cells and stained glutaraldehyde-fixed IBDC virus plaques but not surrounding uninfected duck embryo cells in vitro. Antibody 2C11 did not react with duck embryo cells infected with falcon herpesvirus, psittacine herpesvirus, infectious laryngotracheitis, pigeon herpesvirus, or duck plague virus. A competitive ELISA using antibody 2C11 identified most sera that were positive in the neutralization test. This antibody will be useful in further characterizing IBDC virus, its pathogenesis, and its natural history.

  2. A novel reporter system for neutralizing and enhancing antibody assay against dengue virus.

    Science.gov (United States)

    Song, Ke-Yu; Zhao, Hui; Jiang, Zhen-You; Li, Xiao-Feng; Deng, Yong-Qiang; Jiang, Tao; Zhu, Shun-Ya; Shi, Pei-Yong; Zhang, Bo; Zhang, Fu-Chun; Qin, E-De; Qin, Cheng-Feng

    2014-02-18

    Dengue virus (DENV) still poses a global public health threat, and no vaccine or antiviral therapy is currently available. Antibody plays distinct roles in controlling DENV infections. Neutralizing antibody is protective against DENV infection, whereas sub-neutralizing concentration of antibody can increase DENV infection, termed antibody-dependent enhancement (ADE). Plaque-based assay represents the most widely accepted method measuring neutralizing or enhancing antibodies. In this study, a novel reporter virus-based system was developed for measuring neutralization and ADE activity. A stable Renilla luciferase reporter DENV (Luc-DENV) that can produce robust luciferase signals in BHK-21 and K562 cells were used to establish the assay and validated against traditional plaque-based assay. Luciferase value analysis using various known DENV-specific monoclonal antibodies showed good repeatability and a well linear correlation with conventional plaque-based assays. The newly developed assay was finally validated with clinical samples from infected animals and individuals. This reporter virus-based assay for neutralizing and enhancing antibody evaluation is rapid, lower cost, and high throughput, and will be helpful for laboratory detection and epidemiological investigation for DENV antibodies.

  3. Hepatitis B and A virus antibodies in alcoholic steatosis and cirrhosis

    DEFF Research Database (Denmark)

    Gluud, C; Aldershvile, J; Henriksen, J

    1982-01-01

    Sera from 74 alcoholics with cirrhosis and 63 alcoholics with steatosis were tested for antibody to hepatitis B surface antigen, to hepatitis B core antigen, and to hepatitis A virus by radioimmunoassay or enzyme-linked immunosorbent assay. No significant difference between the two groups...... of alcoholics could be found concerning the prevalence of these antibodies. The total group of patients had antibody to hepatitis B surface antigen or hepatitis B core antigen, or both, significantly (p less than 0.001) more often (26%) than sex- and age-matched controls (4%). No significant difference...... was found between patients and controls concerning the prevalence of antibody to hepatitis A virus (46% v 40%). In patients with cirrhosis, no correlation between wedged hepatic vein pressure or wedged-to-free hepatic vein pressure and any of the viral antibodies could be established. The present results...

  4. Structure of a Human Astrovirus Capsid-Antibody Complex and Mechanistic Insights into Virus Neutralization

    Energy Technology Data Exchange (ETDEWEB)

    Bogdanoff, Walter A.; Campos, Jocelyn; Perez, Edmundo I.; Yin, Lu; Alexander, David L.; DuBois, Rebecca M. (UCSC)

    2016-11-02

    ABSTRACT

    Human astroviruses (HAstVs) are a leading cause of viral diarrhea in young children, the immunocompromised, and the elderly. There are no vaccines or antiviral therapies against HAstV disease. Several lines of evidence point to the presence of protective antibodies in healthy adults as a mechanism governing protection against reinfection by HAstV. However, development of anti-HAstV therapies is hampered by the gap in knowledge of protective antibody epitopes on the HAstV capsid surface. Here, we report the structure of the HAstV capsid spike domain bound to the neutralizing monoclonal antibody PL-2. The antibody uses all six complementarity-determining regions to bind to a quaternary epitope on each side of the dimeric capsid spike. We provide evidence that the HAstV capsid spike is a receptor-binding domain and that the antibody neutralizes HAstV by blocking virus attachment to cells. We identify patches of conserved amino acids that overlap the antibody epitope and may comprise a receptor-binding site. Our studies provide a foundation for the development of therapies to prevent and treat HAstV diarrheal disease.

    IMPORTANCEHuman astroviruses (HAstVs) infect nearly every person in the world during childhood and cause diarrhea, vomiting, and fever. Despite the prevalence of this virus, little is known about how antibodies in healthy adults protect them against reinfection. Here, we determined the crystal structure of a complex of the HAstV capsid protein and a virus-neutralizing antibody. We show that the antibody binds to the outermost spike domain of the capsid, and we provide evidence that the antibody blocks virus attachment to human cells. Importantly, our findings suggest that a subunit-based vaccine focusing the immune system on the HAstV capsid spike domain could be effective in protecting children against HAstV disease.

  5. Antibody-Induced Internalization of the Human Respiratory Syncytial Virus Fusion Protein.

    Science.gov (United States)

    Leemans, A; De Schryver, M; Van der Gucht, W; Heykers, A; Pintelon, I; Hotard, A L; Moore, M L; Melero, J A; McLellan, J S; Graham, B S; Broadbent, L; Power, U F; Caljon, G; Cos, P; Maes, L; Delputte, P

    2017-07-15

    Respiratory syncytial virus (RSV) infections remain a major cause of respiratory disease and hospitalizations among infants. Infection recurs frequently and establishes a weak and short-lived immunity. To date, RSV immunoprophylaxis and vaccine research is mainly focused on the RSV fusion (F) protein, but a vaccine remains elusive. The RSV F protein is a highly conserved surface glycoprotein and is the main target of neutralizing antibodies induced by natural infection. Here, we analyzed an internalization process of antigen-antibody complexes after binding of RSV-specific antibodies to RSV antigens expressed on the surface of infected cells. The RSV F protein and attachment (G) protein were found to be internalized in both infected and transfected cells after the addition of either RSV-specific polyclonal antibodies (PAbs) or RSV glycoprotein-specific monoclonal antibodies (MAbs), as determined by indirect immunofluorescence staining and flow-cytometric analysis. Internalization experiments with different cell lines, well-differentiated primary bronchial epithelial cells (WD-PBECs), and RSV isolates suggest that antibody internalization can be considered a general feature of RSV. More specifically for RSV F, the mechanism of internalization was shown to be clathrin dependent. All RSV F-targeted MAbs tested, regardless of their epitopes, induced internalization of RSV F. No differences could be observed between the different MAbs, indicating that RSV F internalization was epitope independent. Since this process can be either antiviral, by affecting virus assembly and production, or beneficial for the virus, by limiting the efficacy of antibodies and effector mechanism, further research is required to determine the extent to which this occurs in vivo and how this might impact RSV replication. IMPORTANCE Current research into the development of new immunoprophylaxis and vaccines is mainly focused on the RSV F protein since, among others, RSV F-specific antibodies are

  6. Use of monoclonal antibodies against Hendra and Nipah viruses in an antigen capture ELISA

    Directory of Open Access Journals (Sweden)

    Spiropoulou Christina F

    2010-06-01

    Full Text Available Abstract Background Outbreaks of Hendra (HeV and Nipah (NiV viruses have been reported starting in 1994 and 1998, respectively. Both viruses are capable of causing fatal disease in humans and effecting great economical loss in the livestock industry. Results Through screening of hybridomas derived from mice immunized with γ-irradiated Nipah virus, we identified two secreted antibodies; one reactive with the nucleocapsid (N protein and the other, the phosphoprotein (P of henipaviruses. Epitope mapping and protein sequence alignments between NiV and HeV suggest the last 14 amino acids of the carboxyl terminus of the N protein is the target of the anti-N antibody. The anti-P antibody recognizes an epitope in the amino-terminal half of P protein. These monoclonal antibodies were used to develop two antigen capture ELISAs, one for virus detection and the other for differentiation between NiV and HeV. The lower limit of detection of the capture assay with both monoclonal antibodies was 400 pfu. The anti-N antibody was used to successfully detect NiV in a lung tissue suspension from an infected pig. Conclusion The antigen capture ELISA developed is potentially affordable tool to provide rapid detection and differentiation between the henipaviruses.

  7. PREVALENCE OF ANTIBODIES AGAINST INFLUENZA VIRUS IN NON-VACCINATED EQUINES FROM THE BRAZILIAN PANTANAL

    Directory of Open Access Journals (Sweden)

    Lucas Gaíva E Silva

    2014-12-01

    Full Text Available The prevalence of antibodies against Equine Influenza Virus (EIV was determined in 529 equines living on ranches in the municipality of Poconé, Pantanal area of Brazil, by means of the hemagglutination inhibition test, using subtype H3N8 as antigen. The distribution and possible association among positive animal and ranches were evaluated by the chi-square test, spatial autoregressive and multiple linear regression models. The prevalence of antibodies against EIV was estimated at 45.2% (95% CI 30.2 - 61.1% with titers ranging from 20 to 1,280 HAU. Seropositive equines were found on 92.0% of the surveyed ranches. Equine from non-flooded ranches (66.5% and negativity in equine infectious anemia virus (EIAV (61.7% were associated with antibodies against EIV. No spatial correlation was found among the ranches, but the ones located in non-flooded areas were associated with antibodies against EIV. A negative correlation was found between the prevalence of antibodies against EIV and the presence of EIAV positive animals on the ranches. The high prevalence of antibodies against EIV detected in this study suggests that the virus is circulating among the animals, and this statistical analysis indicates that the movement and aggregation of animals are factors associated to the transmission of the virus in the region.

  8. Detection of antibodies to transmissible gastroenteritis virus of swine by modified autoradiographic test

    Energy Technology Data Exchange (ETDEWEB)

    Stepanek, J; Hampl, J; Franz, J; Mensik, P; Skrobak, F [Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia)

    1982-08-01

    A modified method of autoradiographic determination of virus antibodies of gastroenteritis of swine was developed. It is based on the actual reaction between antigen bound in cells of the infected cell cultures and antibodies in tested sera, which is visualized by rabbit antibodies labelled with /sup 125/I (/sup 125/I RaSw IgG antibody) to porcine IgG, on a sensitive radiograph and evaluated by darkening at the point of positive immunological reaction. Specificity of the test and mutual comparability and reproducibility of the results were confirmed by examining the known positive and negative sera and by a comparison with the results of the virus-neutralization test. Of the 36 examined porcine blood sera, antibodies were only proved autoradiographically in the samples positive also by virus-neutralization. In experimentally infected pigs, the same dynamics of antibody production was recorded by the two tests. They were, however, demonstrated autoradiographically the eighth day after infection, while by virus neutralization test as late as 14th day. Their level increased gradually till 35th day after infection.

  9. Formation of infectious dengue virus-antibody immune complex in vivo in marmosets (Callithrix jacchus) after passive transfer of anti-dengue virus monoclonal antibodies and infection with dengue virus.

    Science.gov (United States)

    Moi, Meng Ling; Ami, Yasushi; Shirai, Kenji; Lim, Chang-Kweng; Suzaki, Yuriko; Saito, Yuka; Kitaura, Kazutaka; Saijo, Masayuki; Suzuki, Ryuji; Kurane, Ichiro; Takasaki, Tomohiko

    2015-02-01

    Infection with a dengue virus (DENV) serotype induces cross-reactive, weakly neutralizing antibodies to different dengue serotypes. It has been postulated that cross-reactive antibodies form a virus-antibody immune complex and enhance DENV infection of Fc gamma receptor (FcγR)-bearing cells. We determined whether infectious DENV-antibody immune complex is formed in vivo in marmosets after passive transfer of DENV-specific monoclonal antibody (mAb) and DENV inoculation and whether infectious DENV-antibody immune complex is detectable using FcγR-expressing cells. Marmosets showed that DENV-antibody immune complex was exclusively infectious to FcγR-expressing cells on days 2, 4, and 7 after passive transfer of each of the mAbs (mAb 4G2 and mAb 6B6C) and DENV inoculation. Although DENV-antibody immune complex was detected, contribution of the passively transferred antibody to overall viremia levels was limited in this study. The results indicate that DENV cross-reactive antibodies form DENV-antibody immune complex in vivo, which is infectious to FcγR-bearing cells but not FcγR-negative cells. © The American Society of Tropical Medicine and Hygiene.

  10. Monitoring of Antibodies Titre Against Canine Distemper Virus in Ferrets Vaccinated with a Live Modified Vaccine

    Directory of Open Access Journals (Sweden)

    L. Pavlačík

    2007-01-01

    Full Text Available A group of five ferrets vaccinated against the canine distemper virus (CDV was evaluated as to the onset of anti-CDV antibody production and the serum levels of the animals were monitored for one year. The ferrets were immunized with a live attenuated vaccine. The vaccination pattern was as follows: primary vaccination at the age of 6 weeks, fi rst revaccination at 30 days after primary vaccination, and second revaccination after another 30 days. Blood samples were taken prior to primary vaccination and then at 30-day intervals (sampling 1 to 12. The whole experimental cycle covered the period of one year from primary vaccination (till the age of 1 year and 6 weeks. Serum samples were analysed for anti-CDV virus-neutralisation antibodies using a virus-neutralisation test using the Onderstepoort CDV strain. All ferrets had zero virus-neutralisation antibody titres before primary vaccination. Two ferrets produced virus-neutralisation antibodies as a response to first revaccination. A stable antibody level (titre 256 was maintained between months 4 and 11 after primary vaccination and a sudden increase in antibody titre (titres 512 and 1024 - 2048 occurred in both animals in months 11 and 12. The reason for the abrupt rise in antibody titres in the two animals remains unclear. No anti-CDV seroconversion was observed in the three remaining animals. Regarding the results obtained in this study we do not consider commonly recommended vaccination with a live attenuated anti-CDV vaccine as an effective method of antibodies induction against distemper in young ferrets.

  11. Seroprevalence of infectious bursal disease virus antibodies in ...

    African Journals Online (AJOL)

    This study was aimed at determining the antibodies of IBDV in some poultry species in Maiduguri, Nigeria. A total of 944 serum samples were collected from village chickens, broilers, layers, ducks, turkeys and geese in Maiduguri and tested for IBDV antibodies using inzyme linked Immunosorbent assay (ELISA) and a ...

  12. Generation and Characterization of Protective Antibodies to Marburg Virus

    Science.gov (United States)

    2017-04-03

    generation of recombinant antibodies for the specific detection of Aspergillus fumigatus. PLoS One, 2009. 4(8): p. e6625. 25. Hust, M., et al., A human...scFv antibody generation pipeline for proteome research. J Biotechnol, 2011. 152(4): p. 159-70. 26. Sambrook J and R. D., Molecular cloning: a

  13. Inactivated H7 Influenza Virus Vaccines Protect Mice despite Inducing Only Low Levels of Neutralizing Antibodies.

    Science.gov (United States)

    Kamal, Ram P; Blanchfield, Kristy; Belser, Jessica A; Music, Nedzad; Tzeng, Wen-Pin; Holiday, Crystal; Burroughs, Ashley; Sun, Xiangjie; Maines, Taronna R; Levine, Min Z; York, Ian A

    2017-10-15

    Avian influenza viruses of the H7 hemagglutinin (HA) subtype present a significant public health threat, as evidenced by the ongoing outbreak of human A(H7N9) infections in China. When evaluated by hemagglutination inhibition (HI) and microneutralization (MN) assays, H7 viruses and vaccines are found to induce lower level of neutralizing antibodies (nAb) than do their seasonal counterparts, making it difficult to develop and evaluate prepandemic vaccines. We have previously shown that purified recombinant H7 HA appear to be poorly immunogenic in that they induce low levels of HI and MN antibodies. In this study, we immunized mice with whole inactivated reverse genetics reassortant (RG) viruses expressing HA and neuraminidase (NA) from 3 different H7 viruses [A/Shanghai/2/2013(H7N9), A/Netherlands/219/2003(H7N7), and A/New York/107/2003(H7N2)] or with human A(H1N1)pdm09 (A/California/07/2009-like) or A(H3N2) (A/Perth16/2009) viruses. Mice produced equivalent titers of antibodies to all viruses as measured by enzyme-linked immunosorbent assay (ELISA). However, the antibody titers induced by H7 viruses were significantly lower when measured by HI and MN assays. Despite inducing very low levels of nAb, H7 vaccines conferred complete protection against homologous virus challenge in mice, and the serum antibodies directed against the HA head region were capable of mediating protection. The apparently low immunogenicity associated with H7 viruses and vaccines may be at least partly related to measuring antibody titers with the traditional HI and MN assays, which may not provide a true measure of protective immunity associated with H7 immunization. This study underscores the need for development of additional correlates of protection for prepandemic vaccines. IMPORTANCE H7 avian influenza viruses present a serious risk to human health. Preparedness efforts include development of prepandemic vaccines. For seasonal influenza viruses, protection is correlated with antibody

  14. Early low-titer neutralizing antibodies impede HIV-1 replication and select for virus escape.

    Directory of Open Access Journals (Sweden)

    Katharine J Bar

    Full Text Available Single genome sequencing of early HIV-1 genomes provides a sensitive, dynamic assessment of virus evolution and insight into the earliest anti-viral immune responses in vivo. By using this approach, together with deep sequencing, site-directed mutagenesis, antibody adsorptions and virus-entry assays, we found evidence in three subjects of neutralizing antibody (Nab responses as early as 2 weeks post-seroconversion, with Nab titers as low as 1∶20 to 1∶50 (IC(50 selecting for virus escape. In each of the subjects, Nabs targeted different regions of the HIV-1 envelope (Env in a strain-specific, conformationally sensitive manner. In subject CH40, virus escape was first mediated by mutations in the V1 region of the Env, followed by V3. HIV-1 specific monoclonal antibodies from this subject mapped to an immunodominant region at the base of V3 and exhibited neutralizing patterns indistinguishable from polyclonal antibody responses, indicating V1-V3 interactions within the Env trimer. In subject CH77, escape mutations mapped to the V2 region of Env, several of which selected for alterations of glycosylation. And in subject CH58, escape mutations mapped to the Env outer domain. In all three subjects, initial Nab recognition was followed by sequential rounds of virus escape and Nab elicitation, with Nab escape variants exhibiting variable costs to replication fitness. Although delayed in comparison with autologous CD8 T-cell responses, our findings show that Nabs appear earlier in HIV-1 infection than previously recognized, target diverse sites on HIV-1 Env, and impede virus replication at surprisingly low titers. The unexpected in vivo sensitivity of early transmitted/founder virus to Nabs raises the possibility that similarly low concentrations of vaccine-induced Nabs could impair virus acquisition in natural HIV-1 transmission, where the risk of infection is low and the number of viruses responsible for transmission and productive clinical

  15. Measles Virus Neutralizing Antibodies in Intravenous Immunoglobulins: Is an Increase by Revaccination of Plasma Donors Possible?

    Science.gov (United States)

    Modrof, Jens; Tille, Björn; Farcet, Maria R; McVey, John; Schreiner, Jessica A; Borders, Charles M; Gudino, Maria; Fitzgerald, Peter; Simon, Toby L; Kreil, Thomas R

    2017-11-15

    We report a screen of plasma donors confirming that widespread use of childhood measles vaccination since 1963 resulted in a decrease in average measles virus antibody titers among plasma donors, which is reflected in intravenous immunoglobulins (IVIGs). The measles virus antibody titer, however, is a potency requirement for IVIGs, as defined in a Food and Drug Administration regulation. To mitigate the decline in measles virus antibody titers in IVIGs and to ensure consistent product release, revaccination of plasma donors was investigated as a means to boost titers. However, revaccination-induced titer increases were only about 2-fold and short-lived. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  16. Evolution of Therapeutic Antibodies, Influenza Virus Biology, Influenza, and Influenza Immunotherapy

    Directory of Open Access Journals (Sweden)

    Urai Chaisri

    2018-01-01

    Full Text Available This narrative review article summarizes past and current technologies for generating antibodies for passive immunization/immunotherapy. Contemporary DNA and protein technologies have facilitated the development of engineered therapeutic monoclonal antibodies in a variety of formats according to the required effector functions. Chimeric, humanized, and human monoclonal antibodies to antigenic/epitopic myriads with less immunogenicity than animal-derived antibodies in human recipients can be produced in vitro. Immunotherapy with ready-to-use antibodies has gained wide acceptance as a powerful treatment against both infectious and noninfectious diseases. Influenza, a highly contagious disease, precipitates annual epidemics and occasional pandemics, resulting in high health and economic burden worldwide. Currently available drugs are becoming less and less effective against this rapidly mutating virus. Alternative treatment strategies are needed, particularly for individuals at high risk for severe morbidity. In a setting where vaccines are not yet protective or available, human antibodies that are broadly effective against various influenza subtypes could be highly efficacious in lowering morbidity and mortality and controlling unprecedented epidemic/pandemic. Prototypes of human single-chain antibodies to several conserved proteins of influenza virus with no Fc portion (hence, no ADE effect in recipients are available. These antibodies have high potential as a novel, safe, and effective anti-influenza agent.

  17. Indirect micro-immunofluorescence test for detecting type-specific antibodies to herpes simplex virus.

    Science.gov (United States)

    Forsey, T; Darougar, S

    1980-02-01

    A rapid indirect micro-immunofluorescence test capable of detecting and differentiating type-specific antibodies to herpes simplex virus is described. The test proved highly sensitive and, in 80 patients with active herpes ocular infection, antibody was detected in 94%. No anti-herpes antibody was detected in a control group of 20 patients with adenovirus infections. Testing of animal sera prepared against herpes simplex virus types 1 and 2 and of human sera from cases of ocular and genital herpes infections showed that the test can differentiate antibodies to the infecting serotypes. Specimens of whole blood, taken by fingerprick, and eye secretions, both collected on cellulose sponges, could be tested by indirect micro-immunofluorescence. Anti-herpes IgG, IgM, and IgA can also be detected.

  18. Prevalence of African swine fever virus and classical swine fever virus antibodies in pigs in Benue State, Nigeria.

    Science.gov (United States)

    Asambe, A; Sackey, A K B; Tekdek, L B

    2018-03-01

    This study investigated the prevalence of African swine fever virus (ASFV) and classical swine fever virus (CSFV) antibodies in pigs in Benue State, Nigeria. Serum samples were collected from a total of 460 pigs, including 416 from 74 piggeries and 44 from Makurdi slaughter slab. The samples were analysed using indirect enzyme-linked immunosorbent assay (ELISA) test kit to detect the presence of ASFV antibodies, while competitive ELISA test kit was used to detect antibodies to CSFV. Our findings showed a total ASF prevalence of 13 (2.8%), while prevalences of 7 (1.7%) and 6 (13.6%) were observed in piggeries and in Makurdi slaughter slab, respectively. However, no CSFV antibody sera were detected in this study. Relatively higher ASFV antibody-positive pigs were detected in the slaughter slab than in piggeries. The difference in prevalence of ASF between the two locations was significantly associated (p = 0.017). These findings suggest the presence of ASFV antibody-positive pig in Benue State, Nigeria. Continuous surveillance and monitoring of these diseases among pigs in Nigeria to prevent any fulminating outbreak are recommended.

  19. Hepatitis C virus antibodies among blood donors in Jos, Nigeria ...

    African Journals Online (AJOL)

    Background: Hepatitis C virus (HCV) is one of the hepatitis agents known to be transmitted through blood and blood products. Hepatitis C virus has been implicated as a major cause of chronic liver disease and hepatocellular carcinoma worldwide. This study was, therefore, undertaken with the objective of determining the ...

  20. Prevalence of antibodies to canine parvovirus and distemper virus in wolves in the Canadian Rocky Mountains.

    Science.gov (United States)

    Nelson, Brynn; Hebblewhite, Mark; Ezenwa, Vanessa; Shury, Todd; Merrill, Evelyn H; Paquet, Paul C; Schmiegelow, Fiona; Seip, Dale; Skinner, Geoff; Webb, Nathan

    2012-01-01

    Wild carnivores are often exposed to diseases via contact with peridomestic host species that travel through the wildland-urban interfaces. To determine the antibody prevalences and relationships to human activity for two common canid pathogens, we sampled 99 wolves (Canis lupus) from 2000 to 2008 for antibodies to canine parvovirus (CPV) and canine distemper virus (CDV) in Banff and Jasper National Parks and surrounding areas of the Canadian Rockies. This population was the source for wolves reintroduced into the Northern Rockies of the US. Of 99 wolves sampled, 94 had detectable antibody to CPV (95%), 24 were antibody-positive for CDV (24%), and 24 had antibodies to both pathogens (24%). We tested whether antibody prevalences for CPV and CDV were higher closer to human activity (roads, town sites, First Nation reserves) and as a function of sex and age class. Wolves ≥2 yr old were more likely to be have antibodies to CPV. For CDV, male wolves, wolves ≥2 yr, and those closer to First Nation reserves were more likely to have antibodies. Overall, however, we found minimal support for human influence on antibody prevalence for CDV and CPV. The similarity between our antibody prevalence results and results from recent studies in Yellowstone National Park suggests that at least in the case of CDV, and perhaps CPV, these could be important pathogens with potential effects on wolf populations.

  1. Identifying the Conditions Under Which Antibodies Protect Against Infection by Equine Infectious Anemia Virus

    Directory of Open Access Journals (Sweden)

    Elissa J. Schwartz

    2014-05-01

    Full Text Available The ability to predict the conditions under which antibodies protect against viral infection would transform our approach to vaccine development. A more complete understanding is needed of antibody protection against lentivirus infection, as well as the role of mutation in resistance to an antibody vaccine. Recently, an example of antibody-mediated vaccine protection has been shown via passive transfer of neutralizing antibodies before equine infectious anemia virus (EIAV infection of horses with severe combined immunodeficiency (SCID. Viral dynamic modeling of antibody protection from EIAV infection in SCID horses may lead to insights into the mechanisms of control of infection by antibody vaccination. In this work, such a model is constructed in conjunction with data from EIAV infection of SCID horses to gain insights into multiple strain competition in the presence of antibody control. Conditions are determined under which wild-type infection is eradicated with the antibody vaccine. In addition, a three-strain competition model is considered in which a second mutant strain may coexist with the first mutant strain. The conditions that permit viral escape by the mutant strains are determined, as are the effects of variation in the model parameters. This work extends the current understanding of competition and antibody control in lentiviral infection, which may provide insights into the development of vaccines that stimulate the immune system to control infection effectively.

  2. Directed Selection of Recombinant Human Monoclonal Antibodies to Herpes Simplex Virus Glycoproteins from Phage Display Libraries

    Science.gov (United States)

    Sanna, Pietro Paolo; Williamson, R. Anthony; de Logu, Alessandro; Bloom, Floyd E.; Burton, Dennis R.

    1995-07-01

    Human monoclonal antibodies have considerable potential in the prophylaxis and treatment of viral disease. However, only a few such antibodies suitable for clinical use have been produced to date. We have previously shown that large panels of human recombinant monoclonal antibodies against a plethora of infectious agents, including herpes simplex virus types 1 and 2, can be established from phage display libraries. Here we demonstrate that facile cloning of recombinant Fab fragments against specific viral proteins in their native conformation can be accomplished by panning phage display libraries against viral glycoproteins "captured" from infected cell extracts by specific monoclonal antibodies immobilized on ELISA plates. We have tested this strategy by isolating six neutralizing recombinant antibodies specific for herpes simplex glycoprotein gD or gB, some of which are against conformationally sensitive epitopes. By using defined monoclonal antibodies for the antigen-capture step, this method can be used for the isolation of antibodies to specific regions and epitopes within the target viral protein. For instance, monoclonal antibodies to a nonneutralizing epitope can be used in the capture step to clone antibodies to neutralizing epitopes, or antibodies to a neutralizing epitope can be used to clone antibodies to a different neutralizing epitope. Furthermore, by using capturing antibodies to more immunodominant epitopes, one can direct the cloning to less immunogenic ones. This method should be of value in generating antibodies to be used both in the prophylaxis and treatment of viral infections and in the characterization of the mechanisms of antibody protective actions at the molecular level.

  3. Development and characterization of novel chimeric monoclonal antibodies for broad spectrum neutralization of rabies virus.

    Directory of Open Access Journals (Sweden)

    Pan Kyeom Kim

    Full Text Available Current post-exposure prophylaxis for rabies virus infection has several limitations in terms of supply, cost, safety, and efficacy. Attempts to replace human or equine rabies immune globulins (HRIG or ERIG have been made by several companies and institutes. We developed potent monoclonal antibodies to neutralize a broad spectrum of rabies viruses by screening hybridomas received from the U.S. Centers for Disease Control and Prevention (CDC. Two kinds of chimeric human antibodies (chimeric #7 and #17 were constructed by cloning the variable regions from selected hybridomas and the constant region of a human antibody. Two antibodies were bound to antigenic site III and I/IV, respectively, and were able to neutralize 51 field isolates of rabies virus that were isolated at different times and places such as Asia, Africa, North America, South America, and Australia. These two antibodies neutralize rabies viruses with high efficacy in an in vivo test using Syrian hamster and mouse models and show low risk for adverse immunogenicity.

  4. Development and characterization of novel chimeric monoclonal antibodies for broad spectrum neutralization of rabies virus.

    Science.gov (United States)

    Kim, Pan Kyeom; Keum, Sun Ju; Osinubi, Modupe O V; Franka, Richard; Shin, Ji Young; Park, Sang Tae; Kim, Man Su; Park, Mi Jung; Lee, Soo Young; Carson, William; Greenberg, Lauren; Yu, Pengcheng; Tao, Xiaoyan; Lihua, Wang; Tang, Qing; Liang, Guodong; Shampur, Madhusdana; Rupprecht, Charles E; Chang, Shin Jae

    2017-01-01

    Current post-exposure prophylaxis for rabies virus infection has several limitations in terms of supply, cost, safety, and efficacy. Attempts to replace human or equine rabies immune globulins (HRIG or ERIG) have been made by several companies and institutes. We developed potent monoclonal antibodies to neutralize a broad spectrum of rabies viruses by screening hybridomas received from the U.S. Centers for Disease Control and Prevention (CDC). Two kinds of chimeric human antibodies (chimeric #7 and #17) were constructed by cloning the variable regions from selected hybridomas and the constant region of a human antibody. Two antibodies were bound to antigenic site III and I/IV, respectively, and were able to neutralize 51 field isolates of rabies virus that were isolated at different times and places such as Asia, Africa, North America, South America, and Australia. These two antibodies neutralize rabies viruses with high efficacy in an in vivo test using Syrian hamster and mouse models and show low risk for adverse immunogenicity.

  5. Impaired antibody response causes persistence of prototypic T cell-contained virus.

    Directory of Open Access Journals (Sweden)

    Andreas Bergthaler

    2009-04-01

    Full Text Available CD8 T cells are recognized key players in control of persistent virus infections, but increasing evidence suggests that assistance from other immune mediators is also needed. Here, we investigated whether specific antibody responses contribute to control of lymphocytic choriomeningitis virus (LCMV, a prototypic mouse model of systemic persistent infection. Mice expressing transgenic B cell receptors of LCMV-unrelated specificity, and mice unable to produce soluble immunoglobulin M (IgM exhibited protracted viremia or failed to resolve LCMV. Virus control depended on immunoglobulin class switch, but neither on complement cascades nor on Fc receptor gamma chain or Fc gamma receptor IIB. Cessation of viremia concurred with the emergence of viral envelope-specific antibodies, rather than with neutralizing serum activity, and even early nonneutralizing IgM impeded viral persistence. This important role for virus-specific antibodies may be similarly underappreciated in other primarily T cell-controlled infections such as HIV and hepatitis C virus, and we suggest this contribution of antibodies be given consideration in future strategies for vaccination and immunotherapy.

  6. Effect of low dose gamma-radiation upon Newcastle disease virus antibody level in chicken

    International Nuclear Information System (INIS)

    Vilic, M.; Gottstein, Z.; Ciglar Grozdanic, I.; Matanovic, K.; Miljanic, S.; Mazija, H.; Kraljevic, P.

    2009-01-01

    The specific antibody response against Newcastle disease virus in the blood serum of chickens hatched from eggs exposed to low dose gamma-radiation was studied. Materials and methods: Two groups of eggs of commercial meat chicken lines were irradiated with the dose of 0.30 Gy 60 Co gamma-rays before incubation and on the 19 th day of incubation, respectively. The same number of eggs unexposed to gamma-radiation served as controls. After hatching the group of chicken hatched from eggs irradiated on the 19 th day of incubation was not vaccinated while the group of chicken hatched from eggs irradiated before incubation was vaccinated on the 14 day. Specific serum anti-Newcastle disease virus antibodies were quantified by the hemagglutination inhibition assay with 4 HA units of Newcastle disease virus La Sota strain. Result: Specific antibody titres against Newcastle disease virus in the blood serum of chickens hatched from eggs irradiated before incubation and vaccinated on the 14 th day significantly increased on the 28 th day. Specific antibody titre against Newcastle disease virus in the blood serum of chickens hatched from eggs irradiated on the 19 th day of incubation and non-vaccinated was significantly higher on the 1 st and 14 th day. Conclusion: Acute irradiation of heavy breeding chicken eggs with the dose of 0.30 Gy 60 Co gamma-rays before incubation and on the 19 th day of incubation could have a stimulative effect on humoral immunity in chickens.

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  8. Enhanced sensitivity in detection of antiviral antibody responses using biotinylation of foot-and-mouth disease virus (FMDV) capsids.

    Science.gov (United States)

    Kenney, Mary; Waters, Ryan A; Rieder, Elizabeth; Pega, Juan; Perez-Filguera, Mariano; Golde, William T

    2017-11-01

    Analysis of the immune response to infection of livestock by foot-and-mouth disease virus (FMDV) is most often reported as the serum antibody response to the virus. While measurement of neutralizing antibody has been sensitive and specific, measurements of the quality of the antibody response are less robust. Determining the immunoglobulin (Ig) isotype of the serum antibody response provides a deeper understanding of the biology of the response and more sensitive methods for these assays will facilitate analyses of B cell mediated immunity. We tested the hypothesis that using the virus as the molecular probe could be achieved by adding tags to the surface of the FMDV capsid, and that would enhance sensitivity in assays for anti-FMDV antibody responses. The use of a FLAG-tagged virus in these assays failed to yield improvement whereas chemically biotinylating the virus capsid resulted in significant enhancement of the signal. Here we describe methods using biotinylated virus for measuring anti-viral antibody in serum and antibody secreting cells (ASCs) in blood that are sensitive and specific. Finally, we describe using the biotinylated virus in flow cytometry where such assays should greatly enhance the analysis of anti-virus antibody producing B cells, allowing the investigator to focus on only the FMDV specific B cells when analyzing the development of the B cell response to either infection or vaccination. Published by Elsevier B.V.

  9. Rabies direct fluorescent antibody test does not inactivate rabies or eastern equine encephalitis viruses.

    Science.gov (United States)

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

    2016-08-01

    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. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. An unexpected antibody response to an engineered influenza virus modifies CD8+ T cell responses.

    Science.gov (United States)

    Thomas, Paul G; Brown, Scott A; Yue, Wen; So, Jenny; Webby, Richard J; Doherty, Peter C

    2006-02-21

    The ovalbumin(323-339) peptide that binds H2I-A(b) was engineered into the globular heads of hemagglutinin (H) molecules from serologically non-cross-reactive H1N1 and H3N2 influenza A viruses, the aim being to analyze recall CD4+ T cell responses in a virus-induced respiratory disease. Prime/challenge experiments with these H1ova and H3ova viruses in H2(b) mice gave the predicted, ovalbumin-specific CD4+ T cell response but showed an unexpectedly enhanced, early expansion of viral epitope-specific CD8+ T cells in spleen and a greatly diminished inflammatory process in the virus-infected respiratory tract. At the same time, the primary antibody response to the H3N2 challenge virus was significantly reduced, an effect that has been associated with preexisting neutralizing antibody in other experimental systems. Analysis of serum from the H1ova-primed mice showed low-level binding to H3ova but not to the wild-type H3N2 virus. Experiments with CD4+ T cell-depleted and Ig-/- mice indicated that this cross-reactive Ig is indeed responsible for the modified pathogenesis after respiratory challenge. Furthermore, the effect does not seem to be virus-dose related, although it does require infection. These findings suggest intriguing possibilities for vaccination and, at the same time, emphasize that engineered modifications in viruses may have unintended immunological consequences.

  11. Hepatitis C virus resistance to broadly neutralizing antibodies measured using replication-competent virus and pseudoparticles.

    Science.gov (United States)

    Wasilewski, Lisa N; Ray, Stuart C; Bailey, Justin R

    2016-11-01

    A better understanding of natural variation in neutralization resistance and fitness of diverse hepatitis C virus (HCV) envelope (E1E2) variants will be critical to guide rational development of an HCV vaccine. This work has been hindered by inadequate genetic diversity in viral panels and by a lack of standardization of HCV entry assays. Neutralization assays generally use lentiviral pseudoparticles expressing HCV envelope proteins (HCVpp) or chimeric full-length viruses that are replication competent in cell culture (HCVcc). There have been few systematic comparisons of specific infectivities of E1E2-matched HCVcc and HCVpp, and to our knowledge, neutralization of E1E2-matched HCVpp and HCVcc has never been compared using a diverse panel of human broadly neutralizing monoclonal antibodies (bNAbs) targeting distinct epitopes. Here, we describe an efficient method for introduction of naturally occurring E1E2 genes into a full-length HCV genome, producing replication-competent chimeric HCVcc. We generated diverse panels of E1E2-matched HCVcc and HCVpp and measured the entry-mediating fitness of E1E2 variants using the two systems. We also compared neutralization of E1E2-matched HCVcc and HCVpp by a diverse panel of human bNAbs targeting epitopes across E1E2. We found no correlation between specific infectivities of E1E2-matched HCVcc versus HCVpp, but found a very strong positive correlation between relative neutralization resistance of these same E1E2-matched HCVcc and HCVpp variants. These results suggest that quantitative comparisons of neutralization resistance of E1E2 variants can be made with confidence using either HCVcc or HCVpp, allowing the use of either or both systems to maximize diversity of neutralization panels.

  12. A humanised murine monoclonal antibody protects mice from Venezuelan equine encephalitis virus, Everglades virus and Mucambo virus when administered up to 48 h after airborne challenge

    International Nuclear Information System (INIS)

    O'Brien, Lyn M.; Goodchild, Sarah A.; Phillpotts, Robert J.; Perkins, Stuart D.

    2012-01-01

    Currently there are no licensed antiviral treatments for the Alphaviruses Venezuelan equine encephalitis virus (VEEV), Everglades virus and Mucambo virus. We previously developed a humanised version of the mouse monoclonal antibody 1A3B-7 (Hu1A3B-7) which exhibited a wide range of reactivity in vitro and was able to protect mice from infection with VEEV. Continued work with the humanised antibody has now demonstrated that it has the potential to be a new human therapeutic. Hu1A3B-7 successfully protected mice from infection with multiple Alphaviruses. The effectiveness of the humanisation process was determined by assessing proliferation responses in human T-cells to peptides derived from the murine and humanised versions of the V H and V L domains. This analysis showed that the number of human T-cell epitopes within the humanised antibody had been substantially reduced, indicating that Hu1A3B-7 may have reduced immunogenicity in vivo.

  13. Radioimmunoassay of antibody e against hepatitis-B virus (HBeAb, anti-HBe)

    International Nuclear Information System (INIS)

    Kselikova, M.; Novak, J.; Urbankova, J.

    1981-01-01

    The Abbott-HBe kit renders possible a radioimmunoassay of antibody e against antigen e of the hepatitis-B virus. This detection proceeds in 2 phases: the higher the antibody-e titer in the examined serum the lower the number of pulses measured. HBeAb occurred in 87 test persons. The antibody was most frequently detected in symptom-free carriers of the surface antigen (80%), furthermore in the medical staff of the departments of infectious hepatitides (39%), in hospitalized patients with infectious hepatitis (36%), and in employees of the first-aid service (25%). In blood donors as control group HBeAb was not detected. (author)

  14. SEROPREVALENCE OF ANTIBODIES TO HEPATITIS A VIRUS IN BLOODDONORS AND PATIENTS IN UNIVERSITY CLINICAL CENTER MARIBOR

    Directory of Open Access Journals (Sweden)

    Božislava Majcen Vivod

    2008-04-01

    Seroprevalence of anti-HAV antibodies declined in last decades in European countries. Inour study 20 % blood donors had antibodies anti-HAV in the group younger than 35 yearsand among patient only 15 % of patients had antibodies in the same group.The use of a vaccine against hepatitis A virus has to be considered for the prevention ofsymptomatic hepatitis, especially in adults at risk for infection, such as those who travel toareas with poor sanitation. Furthermore, they should take into consideration the fact thatthe severity of the disease increases with age

  15. Avian influenza virus antibodies in Pacific Coast Red Knots (Calidris canutus rufa)

    Science.gov (United States)

    Johnson, James A.; DeCicco, Lucas H.; Ruthrauff, Daniel R.; Krauss, Scott; Hall, Jeffrey S.

    2014-01-01

    Prevalence of avian influenza virus (AIV) antibodies in the western Atlantic subspecies of Red Knot (Calidris canutus rufa) is among the highest for any shorebird. To assess whether the frequency of detection of AIV antibodies is high for the species in general or restricted only to C. c. rufa, we sampled the northeastern Pacific Coast subspecies of Red Knot (Calidris canutus roselaari) breeding in northwestern Alaska. Antibodies were detected in 90% of adults and none of the chicks sampled. Viral shedding was not detected in adults or chicks. These results suggest a predisposition of Red Knots to AIV infection. High antibody titers to subtypes H3 and H4 were detected, whereas low to intermediate antibody levels were found for subtypes H10 and H11. These four subtypes have previously been detected in shorebirds at Delaware Bay (at the border of New Jersey and Delaware) and in waterfowl along the Pacific Coast of North America.

  16. Human antibodies to the dengue virus E-dimer epitope have therapeutic activity against Zika virus infection.

    Science.gov (United States)

    Fernandez, Estefania; Dejnirattisai, Wanwisa; Cao, Bin; Scheaffer, Suzanne M; Supasa, Piyada; Wongwiwat, Wiyada; Esakky, Prabagaran; Drury, Andrea; Mongkolsapaya, Juthathip; Moley, Kelle H; Mysorekar, Indira U; Screaton, Gavin R; Diamond, Michael S

    2017-11-01

    The Zika virus (ZIKV) epidemic has resulted in congenital abnormalities in fetuses and neonates. Although some cross-reactive dengue virus (DENV)-specific antibodies can enhance ZIKV infection in mice, those recognizing the DENV E-dimer epitope (EDE) can neutralize ZIKV infection in cell culture. We evaluated the therapeutic activity of human monoclonal antibodies to DENV EDE for their ability to control ZIKV infection in the brains, testes, placentas, and fetuses of mice. A single dose of the EDE1-B10 antibody given 3 d after ZIKV infection protected against lethality, reduced ZIKV levels in brains and testes, and preserved sperm counts. In pregnant mice, wild-type or engineered LALA variants of EDE1-B10, which cannot engage Fcg receptors, diminished ZIKV burden in maternal and fetal tissues, and protected against fetal demise. Because neutralizing antibodies to EDE have therapeutic potential against ZIKV, in addition to their established inhibitory effects against DENV, it may be possible to develop therapies that control disease caused by both viruses.

  17. Anti-human T-lymphotropic virus type-I antibodies in atomic-bomb survivors

    Energy Technology Data Exchange (ETDEWEB)

    Matsuo, Tatsuki; Nakashima, Eiji; Carter, R.L. [Radiation Effects Research Foundation, Nagasaki (Japan). Nagasaki Branch] [and others

    1995-03-01

    Adult T-cell leukemia (ATL), induced by human T-lymphotropic virus type-I (HTLV-I), is endemic in Nagasaki, Japan. To investigate the effects of atomic-bomb radiation on development of this specific type of leukemia, 6182 individuals in the Radiation Effects Research Foundation (RERF) Adult Health Study sample in Hiroshima and Nagasaki were examined for positive rate of HTLV-I antibody. Several lymphocyte parameters were also studied for 70 antibody-positive subjects in Nagasaki. The HTLV-I antibody-positive rate was higher in Nagasaki (6.36%) than in Hiroshima (0.79%) and significantly increased with increasing age, but no association was observed with radiation dose. Whether relationship existed between antibody titer levels and radiation dose among antibody-positive subjects was not clear. The frequency of abnormal lymphocytes tended to be higher in antibody-positive subjects than in antibody-negative subjects, and higher in females than in males regardless of radiation dose. The lymphocyte count was lower in antibody-positive subjects than in antibody-negative subjects and lower in female than in male subjects. No evidence was found to suggest that atomic-bomb radiation plays an important role in HTLV-I infection. (author).

  18. Vaccine-induced anti-HA2 antibodies promote virus fusion and enhance influenza virus respiratory disease.

    Science.gov (United States)

    Khurana, Surender; Loving, Crystal L; Manischewitz, Jody; King, Lisa R; Gauger, Phillip C; Henningson, Jamie; Vincent, Amy L; Golding, Hana

    2013-08-28

    Vaccine-induced disease enhancement has been described in connection with several viral vaccines in animal models and in humans. We investigated a swine model to evaluate mismatched influenza vaccine-associated enhanced respiratory disease (VAERD) after pH1N1 infection. Vaccinating pigs with whole inactivated H1N2 (human-like) virus vaccine (WIV-H1N2) resulted in enhanced pneumonia and disease after pH1N1 infection. WIV-H1N2 immune sera contained high titers of cross-reactive anti-pH1N1 hemagglutinin (HA) antibodies that bound exclusively to the HA2 domain but not to the HA1 globular head. No hemagglutination inhibition titers against pH1N1 (challenge virus) were measured. Epitope mapping using phage display library identified the immunodominant epitope recognized by WIV-H1N2 immune sera as amino acids 32 to 77 of pH1N1-HA2 domain, close to the fusion peptide. These cross-reactive anti-HA2 antibodies enhanced pH1N1 infection of Madin-Darby canine kidney cells by promoting virus membrane fusion activity. The enhanced fusion activity correlated with lung pathology in pigs. This study suggests a role for fusion-enhancing anti-HA2 antibodies in VAERD, in the absence of receptor-blocking virus-neutralizing antibodies. These findings should be considered during the evaluation of universal influenza vaccines designed to elicit HA2 stem-targeting antibodies.

  19. Prevalence of Hepatitis A Virus Antibody in Portuguese Travelers: A New Paradigm.

    Science.gov (United States)

    Rocha, Sónia; Tejo, Sandra; Ferreira, Eugénia; Trindade, Luís; Rabadão, Eduardo; Marques, Nuno; Saraiva da Cunha, José

    2017-08-31

    In Portugal, the prevalence of hepatitis A virus infection has decreased in the past decades, especially in young adults. The aim of this study was to detect the prevalence of antibody to hepatitis A virus in a population observed in our Travel Clinic. Antibodies against hepatitis A, hepatitis B, hepatitis C and human immunodeficiency virus were tested using standard enzyme immunoassay in patients older than 18. The exclusion criteria were: prior vaccination for hepatitis A virus, previous diagnosis of infection with hepatitis B virus, hepatitis C virus and/or human immunodeficiency virus, foreign travelers and long-term expatriates. We applied an epidemiological survey and data was statistically analyzed with SPSS® 18.0. In the 665 travelers studied, natural immunity to hepatitis A virus was present in 57.6% (n = 383). They were stratified into 8 age groups and for each one hepatitis A immunity was clarified: 5.0% (n = 1) in 18 - 25 years, 32.3% (n = 21) in 26 - 30 years, 40.9% (n = 47) in 31 - 35 years, 45.8% (n = 54) in 36 - 40 years, 68.7% (n = 79) in 41 - 45 years, 70.1% (n = 68) in 46 - 50 years, 80.8% (n = 63) in 51 - 55 years and 87.7% (n = 50) over 56 years old. In those who accepted further screening, positivity for hepatitis B core antibody was found in 0.6% (n = 3) travelers, hepatitis C virus infection in 1.1% (n = 6) and human immunodeficiency virus infection in 0.5% (n = 3) whose previous status was unknown. The most frequent travel destination was sub-Saharan Africa (72.6%; n = 483). We found 49.1% (n = 260) travelers under 50 years old susceptible to hepatitis A virus infection and for those between 40 and 50 years, 30.7% (n = 65) still need vaccine protection. Across age groups there is a trend towards lower prevalence of hepatitis A virus antibody, in particular among youngsters, when compared with older Portuguese studies.

  20. Anti-Idiotypic Antibodies Specific to prM Monoantibody Prevent Antibody Dependent Enhancement of Dengue Virus Infection

    Directory of Open Access Journals (Sweden)

    Miao Wang

    2017-05-01

    Full Text Available Dengue virus (DENV co-circulates as four serotypes (DENV1-4. Primary infection only leads to self-limited dengue fever. But secondary infection with another serotype carries a higher risk of increased disease severity, causing life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS. Serotype cross-reactive antibodies facilitate DENV infection in Fc-receptor-bearing cells by promoting virus entry via Fcγ receptors (FcγR, a process known as antibody dependent enhancement (ADE. Most studies suggested that enhancing antibodies were mainly specific to the structural premembrane protein (prM of DENV. However, there is still no effective drugs or vaccines to prevent ADE. In this study, we firstly confirmed that both DENV-2 infected human sera (anti-DENV-2 and DENV-2 prM monoclonal antibody (prM mAb could significantly enhance DENV-1 infection in K562 cells. Then we developed anti-idiotypic antibodies (prM-AIDs specific to prM mAb by immunizing of Balb/c mice. Results showed that these polyclonal antibodies can dramatically reduce ADE phenomenon of DENV-1 infection in K562 cells. To further confirm the anti-ADE effect of prM-AIDs in vivo, interferon-α and γ receptor-deficient mice (AG6 were used as the mouse model for DENV infection. We found that administration of DENV-2 prM mAb indeed caused a higher DENV-1 titer as well as interleukin-10 (IL-10 and alaninea minotransferase (ALT in mice infected with DENV-1, similar to clinical ADE symptoms. But when we supplemented prM-AIDs to DENV-1 challenged AG6 mice, the viral titer, IL-10 and ALT were obviously decreased to the negative control level. Of note, the number of platelets in peripheral blood of prM-AIDs group were significantly increased at day 3 post infection with DENV-1 compared that of prM-mAb group. These results confirmed that our prM-AIDs could prevent ADE not only in vitro but also in vivo, suggested that anti-idiotypic antibodies might be a new choice to be considered to

  1. Anti-Idiotypic Antibodies Specific to prM Monoantibody Prevent Antibody Dependent Enhancement of Dengue Virus Infection.

    Science.gov (United States)

    Wang, Miao; Yang, Fan; Huang, Dana; Huang, Yalan; Zhang, Xiaomin; Wang, Chao; Zhang, Shaohua; Zhang, Renli

    2017-01-01

    Dengue virus (DENV) co-circulates as four serotypes (DENV1-4). Primary infection only leads to self-limited dengue fever. But secondary infection with another serotype carries a higher risk of increased disease severity, causing life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). Serotype cross-reactive antibodies facilitate DENV infection in Fc-receptor-bearing cells by promoting virus entry via Fcγ receptors (FcγR), a process known as antibody dependent enhancement (ADE). Most studies suggested that enhancing antibodies were mainly specific to the structural premembrane protein (prM) of DENV. However, there is still no effective drugs or vaccines to prevent ADE. In this study, we firstly confirmed that both DENV-2 infected human sera (anti-DENV-2) and DENV-2 prM monoclonal antibody (prM mAb) could significantly enhance DENV-1 infection in K562 cells. Then we developed anti-idiotypic antibodies (prM-AIDs) specific to prM mAb by immunizing of Balb/c mice. Results showed that these polyclonal antibodies can dramatically reduce ADE phenomenon of DENV-1 infection in K562 cells. To further confirm the anti-ADE effect of prM-AIDs in vivo , interferon-α and γ receptor-deficient mice (AG6) were used as the mouse model for DENV infection. We found that administration of DENV-2 prM mAb indeed caused a higher DENV-1 titer as well as interleukin-10 (IL-10) and alaninea minotransferase (ALT) in mice infected with DENV-1, similar to clinical ADE symptoms. But when we supplemented prM-AIDs to DENV-1 challenged AG6 mice, the viral titer, IL-10 and ALT were obviously decreased to the negative control level. Of note, the number of platelets in peripheral blood of prM-AIDs group were significantly increased at day 3 post infection with DENV-1 compared that of prM-mAb group. These results confirmed that our prM-AIDs could prevent ADE not only in vitro but also in vivo , suggested that anti-idiotypic antibodies might be a new choice to be considered to treat

  2. Adjuvant-Mediated Epitope Specificity and Enhanced Neutralizing Activity of Antibodies Targeting Dengue Virus Envelope Protein

    Directory of Open Access Journals (Sweden)

    Denicar Lina Nascimento Fabris Maeda

    2017-09-01

    Full Text Available The heat-labile toxins (LT produced by enterotoxigenic Escherichia coli display adjuvant effects to coadministered antigens, leading to enhanced production of serum antibodies. Despite extensive knowledge of the adjuvant properties of LT derivatives, including in vitro-generated non-toxic mutant forms, little is known about the capacity of these adjuvants to modulate the epitope specificity of antibodies directed against antigens. This study characterizes the role of LT and its non-toxic B subunit (LTB in the modulation of antibody responses to a coadministered antigen, the dengue virus (DENV envelope glycoprotein domain III (EDIII, which binds to surface receptors and mediates virus entry into host cells. In contrast to non-adjuvanted or alum-adjuvanted formulations, antibodies induced in mice immunized with LT or LTB showed enhanced virus-neutralization effects that were not ascribed to a subclass shift or antigen affinity. Nonetheless, immunosignature analyses revealed that purified LT-adjuvanted EDIII-specific antibodies display distinct epitope-binding patterns with regard to antibodies raised in mice immunized with EDIII or the alum-adjuvanted vaccine. Notably, the analyses led to the identification of a specific EDIII epitope located in the EF to FG loop, which is involved in the entry of DENV into eukaryotic cells. The present results demonstrate that LT and LTB modulate the epitope specificity of antibodies generated after immunization with coadministered antigens that, in the case of EDIII, was associated with the induction of neutralizing antibody responses. These results open perspectives for the more rational development of vaccines with enhanced protective effects against DENV infections.

  3. Bluetongue virus: comparative evaluation of enzyme-linked immunosorbent assay, immunodiffusion, and serum neutralization for detection of viral antibodies.

    OpenAIRE

    Poli, G; Stott, J; Liu, Y S; Manning, J S

    1982-01-01

    Comparative studies on the detection of bovine serum immunoglobulin G antibodies to bluetongue virus with an enzyme-linked immunosorbent assay, an immunodiffusion method, and a serum neutralization assay demonstrated complete concordance between the enzyme-linked immunosorbent assay and the serum neutralization assay results. However, the immunodiffusion method failed to detect bluetongue virus antibody in a substantial number of sera found to possess bluetongue virus immunoglobulin G with th...

  4. Antibodies against Severe Fever with Thrombocytopenia Syndrome Virus in Healthy Persons, China, 2013

    Science.gov (United States)

    Zhang, Lei; Sun, Jimin; Yan, Jie; Lv, Huakun; Chai, Chengliang; Sun, Yi; Shao, Bin; Jiang, Jianmin; Chen, Zhiping

    2014-01-01

    In June 2013, a subclinical infection with severe fever with thrombocytopenia syndrome virus (SFTSV) was detected in Zhejiang Province, China, prompting seroprevalence studies in 6 districts within the province. Of 986 healthy persons tested, 71 had IgG antibodies against SFTSV. This finding suggests that most natural infections with SFTSV are mild or subclinical. PMID:25061813

  5. Expression of Recombinant Potato leafroll virus Structural and Non-structural Proteins for Antibody Production

    Czech Academy of Sciences Publication Activity Database

    Plchová, Helena; Moravec, Tomáš; Dědič, P.; Čeřovská, Noemi

    2011-01-01

    Roč. 159, č. 2 (2011), s. 130-132 ISSN 0931-1785 R&D Projects: GA MŠk 1M06030; GA MZe QH71123 Institutional research plan: CEZ:AV0Z50380511 Keywords : Potato leafroll virus * recombinant viral antigen * antibody production Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.791, year: 2011

  6. Prevalence of antibodies against canine distemper virus among red foxes in Luxembourg

    NARCIS (Netherlands)

    B.C. Damien; S. Losch; J. Mossong; C.P. Muller (Claude); A.D.M.E. Osterhaus (Albert); B.E.E. Martina (Byron)

    2002-01-01

    textabstractCanine distemper virus (CDV) has a wide host spectrum, and during the past years, distemper has been observed in species that were previously not considered to be susceptible. In this study, we investigated the prevalence of CDV-specific antibodies in red foxes (Vulpes vulpes) sampled

  7. Prevalence of antibodies against canine distemper virus among red foxes in Luxembourg.

    NARCIS (Netherlands)

    B.C. Damien; B.E.E. Martina (Byron); S. Losch; A.D.M.E. Osterhaus (Albert); C.P. Muller (Claude)

    2002-01-01

    textabstractCanine distemper virus (CDV) has a wide host spectrum, and during the past years, distemper has been observed in species that were previously not considered to be susceptible. In this study, we investigated the prevalence of CDV-specific antibodies in red foxes (Vulpes vulpes) sampled

  8. Antibodies to a strain-specific citrullinated Epstein-Barr virus peptide diagnoses rheumatoid arthritis

    DEFF Research Database (Denmark)

    Trier, Nicole Hartwig; Holm, Bettina Eide; Heiden, Julie

    2018-01-01

    Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease. Anti-citrullinated protein antibodies (ACPA) are crucial for the serological diagnosis of RA, where Epstein-Barr virus (EBV) has been suggested to be an environmental agent in triggering the onset of the disease. This study aimed...

  9. Antibody-dependent enhancement of dengue virus infection is inhibited by SA-17, a doxorubicin derivative

    NARCIS (Netherlands)

    Ayala Nunez, Vanesa; Jarupathirun, Patsaporn; Kaptein, Suzanne; Neyts, Johan; Smit, Jolanda

    2013-01-01

    Antibody-dependent enhancement (ADE) is thought to play a critical role in the exacerbation of dengue virus (DENV)-induced disease during a heterologous re-infection. Despite ADE's clinical impact, only a few antiviral compounds have been assessed for their anti-ADE activity. We reported earlier

  10. EPSTEIN-BARR VIRUS INFECTIONS – AVIDITY TEST FOR IgG ANTIBODIES

    Directory of Open Access Journals (Sweden)

    Katja Strašek

    2001-06-01

    Full Text Available Background. We wish to introduce specific IgG avidity test as a supplementary assay in serological screening for Epstein-Barr virus infection if the status of patient cannot be resolved from a single serum sample with routine testing.Methods. Avidity of IgG antibodies was determined in sera of 57 patients with different stage of Epstein-Barr virus infection. Enzyme-immuno assay was used with a short incubation of 6-molar urea included in the procedure. Urea should remove low avidity antibodies. Avidity was expressed as the avidity index. Avidity testing with commercial kit was done as well.Results. Low avidity index was found for IgG antibodies of acute phase sera and high for those of past infection, recent infection and reactivation of endogenic virus.Conclusions. Avidity test for IgG antibodies might be supplementary assay to prove acute infection but also to resolve some other clinical states related to Epstein-Barr virus.

  11. Prevalence of Avian Origin H5 and H7 Influenza Virus Antibodies in ...

    African Journals Online (AJOL)

    As part of ongoing influenza surveillance efforts in livestock and companion animals in Nigeria, a study was conducted to investigate the prevalence of avian H5 and H7 influenza virus antibodies in exotic and Nigerian village dogs in Ibadan and Sagamu, two cities in Oyo and Ogun states respectively. One hundred and ...

  12. Survey of citrus tristeza virus populations in Central California that react with MCA13 monoclonal antibody

    Science.gov (United States)

    The Citrus Pest Detection Program (CPDP) of the Central California Tristeza Eradication Agency monitors Citrus tristeza virus (CTV) in Central California. MCA13 is a severe strain discriminating monoclonal antibody used to screen for potentially virulent CTV isolates. MCA13-reactive CTV isolates are...

  13. Antibodies against severe fever with Thrombocytopenia syndrome Virus in healthy persons, China, 2013

    NARCIS (Netherlands)

    Zhang Lei, Lei; Sun, J.; Yan, J.; Huakun, L.; Chai, C.Y.; Sun, Y.; Shao, B.; Jiang, J.D.; Chen, Z.; Kortekaas, J.A.; Zhang, Y.

    2014-01-01

    In June 2013, a subclinical infection with severe fever with thrombocytopenia syndrome virus (SFTSV) was detected in Zhejiang Province, China, prompting seroprevalence studies in 6 districts within the province. Of 986 healthy persons tested, 71 had IgG antibodies against SFTSV. This finding

  14. Production of Polyclonal Antibodies to Potato virus X Using Recombinant Coat Protein

    Czech Academy of Sciences Publication Activity Database

    Čeřovská, Noemi; Moravec, Tomáš; Plchová, Helena; Hoffmeisterová, Hana; Kmoníčková, Jitka; Dědič, P.

    2010-01-01

    Roč. 158, č. 1 (2010), s. 66-68 ISSN 0931-1785 R&D Projects: GA MŠk 1M06030 Institutional research plan: CEZ:AV0Z50380511 Keywords : Potato virus X * recombinant viral antigen * antibodies Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.937, year: 2010

  15. Evaluation of six immunoassays for detection of dengue virus-specific immunoglobulin M and G antibodies

    NARCIS (Netherlands)

    J. Groen (Jan); P. Koraka (Penelope); J. Velzing (Jans); C. Copra (Cederick); A.D.M.E. Osterhaus (Albert)

    2000-01-01

    textabstractThe performance of six commercially available immunoassay systems for the detection of dengue virus-specific immunoglobulin M (IgM) and IgG antibodies in serum was evaluated. These included two IgM and IgG enzyme immunoassays (EIA) from MRL Laboratories and PanBio, a rapid

  16. Isotypes of Epstein-Barr Virus Antibodies in Rheumatoid Arthritis: Association with Rheumatoid Factors and Citrulline-Dependent Antibodies

    Directory of Open Access Journals (Sweden)

    Marie Wulff Westergaard

    2015-01-01

    Full Text Available In order to study the humoral immune response against Epstein-Barr virus (EBV in patients with rheumatoid arthritis (RA and to compare it with the two major autoantibody types in RA, plasma samples from 77 RA patients, 28 patients with systemic lupus erythematosus (SLE, and 28 healthy controls (HCs were investigated by enzyme-linked immunosorbent assays (ELISA. Increased percentages of positives and concentrations of IgG/IgA/IgM antibodies against the latent EBV nuclear antigen-1 (EBNA-1 were observed in RA patients compared to SLE patients and HCs. Increased concentrations and percentages of positives of IgG/IgA/IgM against the early lytic EBV antigen diffuse (EAD were also found in RA patients compared to HCs but were highest in SLE patients. Furthermore, associations between the elevated EBNA-1 IgA and EBNA-1 IgM levels and the presence of IgM and IgA rheumatoid factors (RFs and anti-citrullinated protein antibodies (ACPAs, IgG and between elevated IgA concentrations against EAD and the presence of RFs and ACPAs in RA patients were found. Thus, RA patients had elevated antibodies of all isotypes characteristic of latent EBV infection (whereas SLE patients had elevated antibodies characteristic of lytic EBV infection. Notably, for IgM and IgA (but not IgG, these were associated with the presence of characteristic RA autoantibodies.

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

    Science.gov (United States)

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

    2013-03-01

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

  18. Antibody Responses to Marburg Virus in Egyptian Rousette Bats and Their Role in Protection against Infection.

    Science.gov (United States)

    Storm, Nadia; Jansen Van Vuren, Petrus; Markotter, Wanda; Paweska, Janusz T

    2018-02-10

    Egyptian rousette bats (ERBs) are reservoir hosts for the Marburg virus (MARV). The immune dynamics and responses to MARV infection in ERBs are poorly understood, and limited information exists on the role of antibodies in protection of ERBs against MARV infection. Here, we determine the duration of maternal immunity to MARV in juvenile ERBs, and evaluate the duration of the antibody response to MARV in bats naturally or experimentally infected with the virus. We further explore whether antibodies in previously naturally exposed bats is fully protective against experimental reinfection with MARV. Maternal immunity was lost in juvenile ERBs by 5 months of age. Antibodies to MARV remained detectable in 67% of experimentally infected bats approximately 4 months post inoculation (p.i.), while antibodies to MARV remained present in 84% of naturally exposed bats at least 11 months after capture. Reinfection of seropositive ERBs with MARV produced an anamnestic response from day 5 p.i. Although PCR-defined viremia was present in 73.3% of reinfected ERBs, replicating virus was recovered from the serum of only one bat on day 3 p.i. The negative PCR results in the salivary glands, intestines, bladders and reproductive tracts of reinfected bats, and the apparent absence of MARV in the majority of swabs collected from these bats suggest that reinfection may only play a minor role in the transmission and maintenance of MARV amongst ERBs in nature.

  19. Influenza A virus H5-specific antibodies in mute swans (Cygnus olor) in the USA.

    Science.gov (United States)

    Kistler, Whitney M; Stallknecht, David E; Lebarbenchon, Camille; Pedersen, Kerri; Marks, David R; Mickley, Randy; DeLiberto, Thomas J; Yabsley, Michael J

    2015-04-01

    The use of serologic assays for influenza A virus (IAV) surveillance in wild birds has increased because of the availability of commercial enzyme-linked immunosorbent assays (ELISAs). Recently, an H5-specific blocking ELISA (bELISA) was shown to reliably detect H5-specific antibodies to low- and high-pathogenic H5 viruses in experimentally infected waterfowl. Mute Swans (Cygnus olor) were frequently associated with highly pathogenic H5N1 outbreaks in Europe and may have a similar role if highly pathogenic H5N1 is introduced into North America. We measured the prevalence of antibodies to the nucleoprotein and H5 protein in Mute Swans using three serologic assays. We collected 340 serum samples from Mute Swans in Michigan, New Jersey, New York, and Rhode Island, US. We detected antibodies to the IAV nucleoprotein in 66.2% (225/340) of the samples. We detected H5-specific antibodies in 62.9% (214/340) and 18.8% (64/340) using a modified H5 bELISA protocol and hemagglutination inhibition (HI) assay, respectively. The modified H5 bELISA protocol detected significantly more positive samples than did the manufacturer's protocol. We also tested 46 samples using virus neutralization. Neutralization results had high agreement with the modified H5 bELISA protocol and detected a higher prevalence than did the HI assay. These results indicate that North American Mute Swans have high nucleoprotein and H5 antibody prevalences.

  20. Pichia pastoris-Expressed Bivalent Virus-Like Particulate Vaccine Induces Domain III-Focused Bivalent Neutralizing Antibodies without Antibody-Dependent Enhancement in Vivo

    OpenAIRE

    Rahul Shukla; Ravi K. Rajpoot; Upasana Arora; Ankur Poddar; Sathyamangalam Swaminathan; Navin Khanna; Navin Khanna; Navin Khanna

    2018-01-01

    Dengue, a significant public health problem in several countries around the world, is caused by four different serotypes of mosquito-borne dengue viruses (DENV-1, -2, -3, and -4). Antibodies to any one DENV serotype which can protect against homotypic re-infection, do not offer heterotypic cross-protection. In fact, cross-reactive antibodies may augment heterotypic DENV infection through antibody-dependent enhancement (ADE). A recently launched live attenuated vaccine (LAV) for dengue, which ...

  1. Immunoglobulin E antibodies to pollens augmented in dogs by virus vaccines.

    Science.gov (United States)

    Frick, O L; Brooks, D L

    1983-03-01

    An inbred "atopic dog colony" was established to study the effect of viruses on immunoregulation of immunoglobulin (Ig) E antibodies. Dogs were selected for high skin reactivity to grass and weed pollens. Their offspring were inoculated with pollen extracts in alum immediately after routine vaccinations (attenuated live-virus vaccines for canine distemper and infectious canine hepatitis, and a killed bacterin for Leptospira). Heat labile antipollen IgE antibodies were measured by passive cutaneous anaphylaxis. Pups vaccinated for canine distemper before being given pollen extracts had many more IgE antibodies than did their control littermates who were not vaccinated until after the last pollen extract injection. This may be a natural example of the "allergic break-through phenomenon."

  2. Seroprevalence of Hepatitis A Virus Antibodies among the Patients with Chronic Hepatitis B in Turkey.

    Science.gov (United States)

    Tulek, Necla; Ozsoy, Metin; Moroglu, Cigdem; Cagla Sonmezer, Meliha; Temocin, Fatih; Tuncer Ertem, Gunay; Sebnem Erdinc, Fatma

    2015-01-01

    Hepatitis A virus (HAV) can cause significant pathology in patients with chronic hepatitis B virus (HBV), however, HAV can be prevented by vaccination. The aim of this study was to determine the implication of vaccination against HAV vaccine in patients with chronic hepatitis B. The seroprevalence of anti-HAV IgG antibodies was investigated in the patients with chronic hepatitis B. Anti-HAV IgG antibodies were detected by commercially available ELISA kit. A total of 673 patients (354 males, 319 females with age range of 17-78 years) with chronic hepatitis B were included the study. Hepatitis A virus seropositivity rate was 34% in the patients younger than 20 years, 79% in the age group of 20 to 29 years, and 100% after 35 years of age. Hepatitis A virus vaccination may be recommended for young adult patients with chronic hepatitis B in Turkey. Tulek N, Ozsoy M, Moroglu C, Sonmezer MC, Temocin F, Ertem GT, Erdinc FS. Seroprevalence of Hepatitis A Virus Antibodies among the Patients with Chronic Hepatitis B in Turkey. Euroasian J Hepato-Gastroenterol 2015;5(2):95-97.

  3. Applying antibody-sensitive hypervariable region 1-deleted hepatitis C virus to the study of escape pathways of neutralizing human monoclonal antibody AR5A

    DEFF Research Database (Denmark)

    Velazquez-Moctezuma, Rodrigo; Law, Mansun; Bukh, Jens

    2017-01-01

    Hepatitis C virus (HCV) is a major cause of end-stage liver diseases. With 3–4 million new HCV infections yearly, a vaccine is urgently needed. A better understanding of virus escape from neutralizing antibodies and their corresponding epitopes are important for this effort. However, for viral is...

  4. ''reverse'' solid-phase radioimmunoasssay for IgM-antibodies to hepatitis A virus

    Energy Technology Data Exchange (ETDEWEB)

    Meurman, O H; Matter, L; Krishna, R V; Krech, U H [Institute of Medical Microbiology, St. Gallen, Switzerland

    1981-01-01

    A ''reverse'' solid-phase radio-immuno-assay for IgM antibodies to hepatitis A virus (HAV) was developed. Anti-human IgM immunoglobulins were bound on the wells of polyvinylchloride microtiter plates. Serum specimens were incubated in the anti-human IgM coated wells and bound IgM antibodies were then assayed for antigen specificity by subsequent incubations with HAV antigen and /sup 125/I-labelled human anti-HAV IgG. The test showed a high sensitivity and specificity for anti-HAV IgM antibodies. No false-positive reactions were observed either in the sera from patients with hepatobiliary disorders other than HAV infection or in the sera containing both rheumatoid factor and anti-HAV IgG antibodies. In acute HAV infections specific IgM antibodies were present already in the first specimens taken within a few days after the onset of jaundice. The persistence of the IgM antibodies was from 4 to 6 months. IgM antibody titers up to 1,000,000 were observed in the acute phase of HAV infection. In routine diagnostic work the titration of the sera was not necessary, since a reliable qualitative result was obtained by testing the sera in a single dilution of 1:100. A similar reverse immuno-assay principle may be adaptable for the diagnostic determination of IgM antibodies to different viral and microbial antigens.

  5. Recombinant Sheep Pox Virus Proteins Elicit Neutralizing Antibodies.

    Science.gov (United States)

    Chervyakova, Olga V; Zaitsev, Valentin L; Iskakov, Bulat K; Tailakova, Elmira T; Strochkov, Vitaliy M; Sultankulova, Kulyaisan T; Sandybayev, Nurlan T; Stanbekova, Gulshan E; Beisenov, Daniyar K; Abduraimov, Yergali O; Mambetaliyev, Muratbay; Sansyzbay, Abylay R; Kovalskaya, Natalia Y; Nemchinov, Lev G; Hammond, Rosemarie W

    2016-06-07

    The aim of this work was to evaluate the immunogenicity and neutralizing activity of sheep pox virus (SPPV; genus Capripoxvirus, family Poxviridae) structural proteins as candidate subunit vaccines to control sheep pox disease. SPPV structural proteins were identified by sequence homology with proteins of vaccinia virus (VACV) strain Copenhagen. Four SPPV proteins (SPPV-ORF 060, SPPV-ORF 095, SPPV-ORF 117, and SPPV-ORF 122), orthologs of immunodominant L1, A4, A27, and A33 VACV proteins, respectively, were produced in Escherichia coli. Western blot analysis revealed the antigenic and immunogenic properties of SPPV-060, SPPV-095, SPPV-117 and SPPV-122 proteins when injected with adjuvant into experimental rabbits. Virus-neutralizing activity against SPPV in lamb kidney cell culture was detected for polyclonal antisera raised to SPPV-060, SPPV-117, and SPPV-122 proteins. To our knowledge, this is the first report demonstrating the virus-neutralizing activities of antisera raised to SPPV-060, SPPV-117, and SPPV-122 proteins.

  6. Neutralizing antibodies in cats infected with feline immunodeficiency virus.

    NARCIS (Netherlands)

    F. Tozzini; D. Matteucci; P. Bandecchi; F. Baldinotti; C.H.J. Siebelink (Kees); A.D.M.E. Osterhaus (Albert); M. Bendinelli

    1993-01-01

    textabstractSera from cats experimentally infected with five isolates of feline immunodeficiency virus (FIV) from various geographical regions and from FIV enzyme-linked immunosorbent assay-seropositive field cats from four European countries neutralized the Petaluma strain of FIV (FIV-P),

  7. Role of antibodies in controlling dengue virus infection

    NARCIS (Netherlands)

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

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

  8. Recombinant Sheep Pox Virus Proteins Elicit Neutralizing Antibodies

    Directory of Open Access Journals (Sweden)

    Olga V. Chervyakova

    2016-06-01

    Full Text Available The aim of this work was to evaluate the immunogenicity and neutralizing activity of sheep pox virus (SPPV; genus Capripoxvirus, family Poxviridae structural proteins as candidate subunit vaccines to control sheep pox disease. SPPV structural proteins were identified by sequence homology with proteins of vaccinia virus (VACV strain Copenhagen. Four SPPV proteins (SPPV-ORF 060, SPPV-ORF 095, SPPV-ORF 117, and SPPV-ORF 122, orthologs of immunodominant L1, A4, A27, and A33 VACV proteins, respectively, were produced in Escherichia coli. Western blot analysis revealed the antigenic and immunogenic properties of SPPV-060, SPPV-095, SPPV-117 and SPPV-122 proteins when injected with adjuvant into experimental rabbits. Virus-neutralizing activity against SPPV in lamb kidney cell culture was detected for polyclonal antisera raised to SPPV-060, SPPV-117, and SPPV-122 proteins. To our knowledge, this is the first report demonstrating the virus-neutralizing activities of antisera raised to SPPV-060, SPPV-117, and SPPV-122 proteins.

  9. Typing of viral hemorrhagic septicemia virus by monoclonal antibodies

    DEFF Research Database (Denmark)

    Ito, Takafumi; Kurita, Jun; Sano, Motohiko

    2012-01-01

    Seven mAbs with specific reaction patterns against each of the four genotypes and eight subtypes of viral hemorrhagic septicemia virus (VHSV) were produced, aiming to establish an immunoassay for typing VHSV isolates according to their genotype. Among the mAbs, VHS-1.24 reacted with all genotypes...

  10. Universal antibodies against the highly conserved influenza fusion peptide cross-neutralize several subtypes of influenza A virus

    Energy Technology Data Exchange (ETDEWEB)

    Hashem, Anwar M. [Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, ON (Canada); Department of Microbiology, Faculty of Medicine, King Abdulaziz University, Jeddah (Saudi Arabia); Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON (Canada); Van Domselaar, Gary [National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB (Canada); Li, Changgui; Wang, Junzhi [National Institute for the Control of Pharmaceutical and Biological Products, Beijing (China); She, Yi-Min; Cyr, Terry D. [Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, ON (Canada); Sui, Jianhua [Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, 44 Binney Street, Boston, MA 02115 (United States); He, Runtao [National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB (Canada); Marasco, Wayne A. [Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, 44 Binney Street, Boston, MA 02115 (United States); Li, Xuguang, E-mail: Sean.Li@hc-sc.gc.ca [Centre for Vaccine Evaluation, Biologics and Genetic Therapies Directorate, HPFB, Health Canada, Ottawa, ON (Canada); Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON (Canada)

    2010-12-10

    Research highlights: {yields} The fusion peptide is the only universally conserved epitope in all influenza viral hemagglutinins. {yields} Anti-fusion peptide antibodies are universal antibodies that cross-react with all influenza HA subtypes. {yields} The universal antibodies cross-neutralize different influenza A subtypes. {yields} The universal antibodies inhibit the fusion process between the viruses and the target cells. -- Abstract: The fusion peptide of influenza viral hemagglutinin plays a critical role in virus entry by facilitating membrane fusion between the virus and target cells. As the fusion peptide is the only universally conserved epitope in all influenza A and B viruses, it could be an attractive target for vaccine-induced immune responses. We previously reported that antibodies targeting the first 14 amino acids of the N-terminus of the fusion peptide could bind to virtually all influenza virus strains and quantify hemagglutinins in vaccines produced in embryonated eggs. Here we demonstrate that these universal antibodies bind to the viral hemagglutinins in native conformation presented in infected mammalian cell cultures and neutralize multiple subtypes of virus by inhibiting the pH-dependant fusion of viral and cellular membranes. These results suggest that this unique, highly-conserved linear sequence in viral hemagglutinin is exposed sufficiently to be attacked by the antibodies during the course of infection and merits further investigation because of potential importance in the protection against diverse strains of influenza viruses.

  11. Universal antibodies against the highly conserved influenza fusion peptide cross-neutralize several subtypes of influenza A virus

    International Nuclear Information System (INIS)

    Hashem, Anwar M.; Van Domselaar, Gary; Li, Changgui; Wang, Junzhi; She, Yi-Min; Cyr, Terry D.; Sui, Jianhua; He, Runtao; Marasco, Wayne A.; Li, Xuguang

    2010-01-01

    Research highlights: → The fusion peptide is the only universally conserved epitope in all influenza viral hemagglutinins. → Anti-fusion peptide antibodies are universal antibodies that cross-react with all influenza HA subtypes. → The universal antibodies cross-neutralize different influenza A subtypes. → The universal antibodies inhibit the fusion process between the viruses and the target cells. -- Abstract: The fusion peptide of influenza viral hemagglutinin plays a critical role in virus entry by facilitating membrane fusion between the virus and target cells. As the fusion peptide is the only universally conserved epitope in all influenza A and B viruses, it could be an attractive target for vaccine-induced immune responses. We previously reported that antibodies targeting the first 14 amino acids of the N-terminus of the fusion peptide could bind to virtually all influenza virus strains and quantify hemagglutinins in vaccines produced in embryonated eggs. Here we demonstrate that these universal antibodies bind to the viral hemagglutinins in native conformation presented in infected mammalian cell cultures and neutralize multiple subtypes of virus by inhibiting the pH-dependant fusion of viral and cellular membranes. These results suggest that this unique, highly-conserved linear sequence in viral hemagglutinin is exposed sufficiently to be attacked by the antibodies during the course of infection and merits further investigation because of potential importance in the protection against diverse strains of influenza viruses.

  12. Antibodies against Hepatitis A and Hepatitis B Virus in Intravenous Immunoglobulin Products.

    Science.gov (United States)

    Lee, Soyoung; Kim, Han Wool; Kim, Kyung Hyo

    2016-12-01

    The worldwide seroprevalence of hepatitis A virus (HAV) and hepatitis B virus (HBV) has changed over the last two decades, indicating a declining incidence of HAV and HBV infections. Therefore, vaccinations against HAV and HBV are recommended for unimmunized people before traveling to an endemic area. Unfortunately, primary antibody deficiency (PAD) patients can only obtain humoral immunity through intravenous immunoglobulin G (IVIG) replacement and not from vaccination because of a defect in antibody production. However, few studies have analyzed the titers of antibodies against HAV or HBV in IVIG products. In this study, the titers of anti-HAV and anti-HBs antibodies were measured in nineteen lots of IVIG products from five manufacturers from three countries (A, B from Korea; C, D from Japan; and E from the USA), and trough titers in plasma were estimated. Concentrations of anti-HAV antibody ranged from 1,888-8,927 mIU/mL and estimated trough titers exceeded the minimal protective value in all evaluated IVIG products. Concentrations of anti-HBs antibody ranged from 438-965 mIU/mL in products A and B and were 157, 123, and 1,945 mIU/mL in products C, D, and E, respectively. Estimated trough titers in products A, B, and E exceeded the minimal protective value but those in products C and D did not reach this threshold. These data demonstrated that available IVIG products generally provide sufficient antibodies against HAV and HBV to protect patients with PAD, although the trough concentrations of anti-HBs antibody in two IVIG products did not reach the minimum protective value.

  13. Intramuscular Adeno-Associated Virus-Mediated Expression of Monoclonal Antibodies Provides 100% Protection Against Ebola Virus Infection in Mice.

    Science.gov (United States)

    van Lieshout, Laura P; Soule, Geoff; Sorensen, Debra; Frost, Kathy L; He, Shihua; Tierney, Kevin; Safronetz, David; Booth, Stephanie A; Kobinger, Gary P; Qiu, Xiangguo; Wootton, Sarah K

    2018-03-05

    The 2013-2016 West Africa outbreak demonstrated the epidemic potential of Ebola virus and highlighted the need for counter strategies. Monoclonal antibody (mAb)-based therapies hold promise as treatment options for Ebola virus infections. However, production of clinical-grade mAbs is labor intensive, and immunity is short lived. Conversely, adeno-associated virus (AAV)-mediated mAb gene transfer provides the host with a genetic blueprint to manufacture mAbs in vivo, leading to steady release of antibody over many months. Here we demonstrate that AAV-mediated expression of nonneutralizing mAb 5D2 or 7C9 confers 100% protection against mouse-adapted Ebola virus infection, while neutralizing mAb 2G4 was 83% protective. A 2-component cocktail, AAV-2G4/AAV-5D2, provided complete protection when administered 7 days prior to challenge and was partially protective with a 3-day lead time. Finally, AAV-mAb therapies provided sustained protection from challenge 5 months following AAV administration. AAV-mAb may be a viable alternative strategy for vaccination against emerging infectious diseases.

  14. Antibodies to henipavirus or henipa-like viruses in domestic pigs in Ghana, West Africa.

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    David T S Hayman

    Full Text Available Henipaviruses, Hendra virus (HeV and Nipah virus (NiV, have Pteropid bats as their known natural reservoirs. Antibodies against henipaviruses have been found in Eidolon helvum, an old world fruit bat species, and henipavirus-like nucleic acid has been detected in faecal samples from E. helvum in Ghana. The initial outbreak of NiV in Malaysia led to over 265 human encephalitis cases, including 105 deaths, with infected pigs acting as amplifier hosts for NiV during the outbreak. We detected non-neutralizing antibodies against viruses of the genus Henipavirus in approximately 5% of pig sera (N = 97 tested in Ghana, but not in a small sample of other domestic species sampled under a E. helvum roost. Although we did not detect neutralizing antibody, our results suggest prior exposure of the Ghana pig population to henipavirus(es. Because a wide diversity of henipavirus-like nucleic acid sequences have been found in Ghanaian E. helvum, we hypothesise that these pigs might have been infected by henipavirus(es sufficiently divergent enough from HeVor NiV to produce cross-reactive, but not cross-neutralizing antibodies to HeV or NiV.

  15. Canine distemper virus DNA vaccination of mink can overcome interference by maternal antibodies.

    Science.gov (United States)

    Jensen, Trine Hammer; Nielsen, Line; Aasted, Bent; Pertoldi, Cino; Blixenkrone-Møller, Merete

    2015-03-10

    Canine distemper virus (CDV) is highly contagious and can cause severe disease against which conventional live vaccines are ineffective in the presence of maternal antibodies. Vaccination in the presences of maternal antibodies was challenged by vaccination of 5 days old and 3 weeks old mink kits with CDV DNA vaccines. Virus neutralising (VN) antibody responses were induced in mink kits vaccinated with a plasmid encoding the haemaglutinin protein (H) of CDV (n=5, pCDV-H) or a combination of the H, fusion (F) and nucleoprotein (N) of CDV (n=5, pCDV-HFN). These DNA vaccinated kits were protected against virulent experimental infection with field strains of CDV. The pCDV-H was more efficient in inducing protective immunity in the presence of maternal antibodies compared to the pCDV-HFN. The results show that DNA vaccination with the pCDV-H or pCDV-HFN (n=4) only given once at 5 days of age induces virus specific immune response in neonatal mink and protection against virulent CDV exposure later in life. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Enzyme-linked immunosorbent Assay for detecting of antibody to canine distemper virus

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    Sudarisman

    2006-03-01

    Full Text Available Serum neutralisation test (SNT has been established for evaluating canine distemper vaccination, but until now SNT was rarely used due to the need for continuous tissue culture facilities and requires 3 days to perform. For detecting antibody to canine distemper virus, an enzyme-linked immunosorbent assay (ELISA is relatively simple and rapid seroassay. ELISA for canine immunoglobulin (Ig G antibodies to canine distemper virus (CDV was developed by using Onderstepoort strain of canine distemper virus as coating antigen. Rabbit anti canine IgG labelled with horse radish peroxidase was used as the conjugate, while phenylenediamine dihydrochloride (OPD was used as the substrate. The ELISA results were then compared with the results of the SNT, using the sera of 312 random-source dogs from West Java. The two test-results had a high degree of correlation. Very few discrepancies occurred and most of these were at the lower limits of each test. When the sera were tested at 1 : 100 dilutions, there was a 95.5% agreement between the ELISA and SNT. Their sensitivity and spesificity were 83.9 and 98.4%. Titrated SNT and ELISA also were performed on sera from 7 dogs whose lifetime medical histories were known. The antibodies were inclining up after two months of post vaccination, where the titre was not in zero/lower position at the day of vaccination. However, antibody zero or low position were found at 28 days post vaccination. All of the results indicated that ELISA can be used for evaluating antibody to canine distemper virus response, replacing the SNT.

  17. A novel, colorimetric neutralization assay for measuring antibodies to influenza viruses.

    Science.gov (United States)

    Lehtoranta, Liisa; Villberg, Anja; Santanen, Riitta; Ziegler, Thedi

    2009-08-01

    A colorimetric cell proliferation assay for measuring neutralizing antibodies to influenza viruses in human sera is described. Following a 90-min incubation, the serum-virus mixture was transferred to Madin-Darby canine kidney cells cultured in 96-well plates. After further incubation for three days, a tetrazolium salt was added to the wells. Cellular mitochondrial dehydrogenases cleave the tetrazolium salt to formazan, and the resulting color change is read by a spectrophotometer. The absorbance values correlate directly to the number of viable cells in the assay well and thus also to the neutralizing activity of influenza-specific antibodies present in the serum. With the few hands-on manipulations required, this assay allows simultaneous testing of a considerable number of sera, offers opportunities for automation, and is suitable for use under biosafety level-3 conditions. The test was used to study the antibody response after the administration of seasonal, inactivated, trivalent influenza vaccine. Antibody titers determined by the neutralization test in pre- and post-vaccination serum pairs were compared with those obtained by the hemagglutination inhibition assay. The neutralization test yielded higher pre- and post-vaccination titers and a larger number of significant increases in post-vaccination antibody titer than the hemagglutination inhibition test. This new test format could serve as a valuable laboratory tool for influenza vaccine studies.

  18. Survey for West Nile virus antibodies in wild ducks, 2004-06, USA

    Science.gov (United States)

    Hofmeister, Erik K.; Jankowski, Mark D.; Goldberg, Diana R.; Franson, J. Christian

    2016-01-01

    Detection of West Nile virus (WNV) in ducks has been reported in North America in isolated cases of mortality in wild waterbirds and following outbreaks in farmed ducks. Although the virus has been noted as an apparent incidental finding in several species of ducks, little is known about the prevalence of exposure or the outcome of infection with WNV in wild ducks in North America. From 2004–06, we collected sera from 1,406 wild-caught American Wigeon (Anas americana), Mallard (Anas platyrhynchos), and Northern Pintail (Anas acuta) ducks at national wildlife refuges (NWRs) in North Dakota and Wood Ducks (Aix sponsa) at NWRs in South Carolina and Tennessee. We measured the prevalence of previous exposure to WNV in these ducks by measuring WNV antibodies and evaluated variation in exposure among species, age, and year. Additionally, we evaluated the performance of a commercial antibody to wild bird immunoglobulin in duck species that varied in their phylogenetic relatedness to the bird species the antibody was directed against. As determined by a screening immunoassay and a confirmatory plaque reduction neutralization assay, the prevalence of WNV antibody was 10%. In light of experimental studies that show ducks to be relatively resistant to mortality caused by WNV, the antibody prevalence we detected suggests that wild ducks may be less-frequently exposed to WNV than expected for birds inhabiting wetlands where they may acquire infection from mosquitoes.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

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

  20. Diagnostic potential of recombinant scFv antibodies generated against hemagglutinin protein of influenza A virus

    Directory of Open Access Journals (Sweden)

    Roopali eRajput

    2015-09-01

    Full Text Available Human influenza A viruses have been the cause of enormous socio-economic losses worldwide. In order to combat such a notorious pathogen, hemagglutinin protein (HA has been a preferred target for generation of neutralizing-antibodies, as potent therapeutic/ diagnostic agents. In the present study, recombinant anti-HA single chain variable fragment (scFv antibodies were constructed using the phage display technology to aid in diagnosis and treatment of human influenza A virus infections. Spleen cells of mice hyper-immunized with A/New Caledonia/20/99 (H1N1 virus were used as the source for recombinant antibody (rAb production. The antigen-binding phages were quantified after 6 rounds of bio-panning against A/New Caledonia/20/99 (H1N1, A/California/07/2009 (H1N1-like, or A/Udorn/307/72(H3N2 viruses. The phage yield was maximum for the A/New Caledonia/20/99 (H1N1, however, considerable cross-reactivity was observed for the other virus strains as well. The HA-specific polyclonal rAb preparation was subjected to selection of single clones for identification of high reactive relatively conserved epitopes. The high affinity rAbs were tested against certain known conserved HA epitopes by peptide ELISA. Three recombinant mAbs showed reactivity with both the H1N1 strains and one (C5 showed binding with all the three viral strains. The C5 antibody was thus used for development of an ELISA test for diagnosis of influenza virus infection. Based on the sample size in the current analysis, the ELISA test demonstrated 83.9% sensitivity and 100% specificity. Thus, the ELISA, developed in our study, may prove as a cheaper alternative to the presently used real time RT-PCR test for detection of human influenza A viruses in clinical specimens, which will be beneficial, especially in the developing countries. Since, the two antibodies identified in this study are reactive to conserved HA epitopes; these may prove as potential therapeutic agents as well.

  1. Development, characterization and application of monoclonal antibodies against Brazilian Dengue virus isolates.

    Directory of Open Access Journals (Sweden)

    Camila Zanluca

    Full Text Available Dengue is the most prevalent human arboviral disease. The morbidity related to dengue infection supports the need for an early, quick and effective diagnostic test. Brazil is a hotspot for dengue, but no serological diagnostic test has been produced using Brazilian dengue virus isolates. This study aims to improve the development of immunodiagnostic methods for dengue virus (DENV detection through the production and characterization of 22 monoclonal antibodies (mAbs against Brazilian isolates of DENV-1, -2 and -3. The mAbs include IgG2bκ, IgG2aκ and IgG1κ isotypes, and most were raised against the envelope or the pre-membrane proteins of DENV. When the antibodies were tested against the four DENV serotypes, different reactivity patterns were identified: group-specific, subcomplex specific (DENV-1, -3 and -4 and DENV-2 and -3 and dengue serotype-specific (DENV-2 or -3. Additionally, some mAbs cross-reacted with yellow fever virus (YFV, West Nile virus (WNV and Saint Louis encephalitis virus (SLEV. None of the mAbs recognized the alphavirus Venezuelan equine encephalitis virus (VEEV. Furthermore, mAbs D3 424/8G, D1 606/A12/B9 and D1 695/12C/2H were used to develop a capture enzyme-linked immunosorbent assay (ELISA for anti-dengue IgM detection in sera from patients with acute dengue. To our knowledge, these are the first monoclonal antibodies raised against Brazilian DENV isolates, and they may be of special interest in the development of diagnostic assays, as well as for basic research.

  2. Conserved epitope on influenza-virus hemagglutinin head defined by a vaccine-induced antibody

    Energy Technology Data Exchange (ETDEWEB)

    Raymond, Donald D.; Bajic, Goran; Ferdman, Jack; Suphaphiphat, Pirada; Settembre, Ethan C.; Moody, M. Anthony; Schmidt, Aaron G.; Harrison, Stephen C. (Duke-MED); (CH-Boston); (Seqirus)

    2017-12-18

    Antigenic variation requires frequent revision of annual influenza vaccines. Next-generation vaccine design strategies aim to elicit a broader immunity by directing the human immune response toward conserved sites on the principal viral surface protein, the hemagglutinin (HA). We describe a group of antibodies that recognize a hitherto unappreciated, conserved site on the HA of H1 subtype influenza viruses. Mutations in that site, which required a change in the H1 component of the 2017 vaccine, had not previously “taken over” among circulating H1 viruses. Our results encourage vaccine design strategies that resurface a protein to focus the immune response on a specific region.

  3. Destructive arthritis in a patient with chikungunya virus infection with persistent specific IgM antibodies

    Directory of Open Access Journals (Sweden)

    Receveur Marie-Catherine

    2009-12-01

    Full Text Available Abstract Background Chikungunya fever is an emerging arboviral disease characterized by an algo-eruptive syndrome, inflammatory polyarthralgias, or tenosynovitis that can last for months to years. Up to now, the pathophysiology of the chronic stage is poorly understood. Case presentation We report the first case of CHIKV infection with chronic associated rheumatism in a patient who developed progressive erosive arthritis with expression of inflammatory mediators and persistence of specific IgM antibodies over 24 months following infection. Conclusions Understanding the specific features of chikungunya virus as well as how the virus interacts with its host are essential for the prevention, treatment or cure of chikungunya disease.

  4. Domestic cat microsphere immunoassays: detection of antibodies during feline immunodeficiency virus infection.

    Science.gov (United States)

    Wood, Britta A; Carver, Scott; Troyer, Ryan M; Elder, John H; VandeWoude, Sue

    2013-10-31

    Microsphere immunoassays (MIAs) allow rapid and accurate evaluation of multiple analytes simultaneously within a biological sample. Here we describe the development and validation of domestic cat-specific MIAs for a) the quantification of total IgG and IgA levels in plasma, and b) the detection of IgG and IgA antibodies to feline immunodeficiency virus (FIV) capsid (CA) and surface (SU) proteins, and feline CD134 in plasma. These assays were used to examine the temporal antibody response of domestic cats infected with apathogenic and pathogenic FIVs, and domestic cats infected with parental and chimeric FIVs of varying pathogenicity. The results from these studies demonstrated that a) total IgG antibodies increase over time after infection; b) α-CA and α-SU IgG antibodies are detectable between 9 and 28 days post-infection and increase over time, and these antibodies combined represent a fraction (1.8 to 21.8%) of the total IgG increase due to infection; c) measurable α-CD134 IgG antibody levels vary among individuals and over time, and are not strongly correlated with viral load; d) circulating IgA antibodies, in general, do not increase during the early stage of infection; and e) total IgG, and α-CA and α-SU IgG antibody kinetics and levels vary with FIV viral strain/pathogenicity. The MIAs described here could be used to screen domestic cats for FIV infection, and to evaluate the FIV-specific or total antibody response elicited by various FIV strains/other diseases. © 2013.

  5. Quantification of Lyssavirus-Neutralizing Antibodies Using Vesicular Stomatitis Virus Pseudotype Particles

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    Sarah Moeschler

    2016-09-01

    Full Text Available Rabies is a highly fatal zoonotic disease which is primarily caused by rabies virus (RABV although other members of the genus Lyssavirus can cause rabies as well. As yet, 14 serologically and genetically diverse lyssaviruses have been identified, mostly in bats. To assess the quality of rabies vaccines and immunoglobulin preparations, virus neutralization tests with live RABV are performed in accordance with enhanced biosafety standards. In the present work, a novel neutralization test is presented which takes advantage of a modified vesicular stomatitis virus (VSV from which the glycoprotein G gene has been deleted and replaced by reporter genes. This single-cycle virus was trans-complemented with RABV envelope glycoprotein. Neutralization of this pseudotype virus with RABV reference serum or immune sera from vaccinated mice showed a strong correlation with the rapid fluorescent focus inhibition test (RFFIT. Importantly, pseudotype viruses containing the envelope glycoproteins of other lyssaviruses were neutralized by reference serum to a significantly lesser extent or were not neutralized at all. Taken together, a pseudotype virus system has been successfully developed which allows the safe, fast, and sensitive detection of neutralizing antibodies directed against different lyssaviruses.

  6. Quantification of Lyssavirus-Neutralizing Antibodies Using Vesicular Stomatitis Virus Pseudotype Particles.

    Science.gov (United States)

    Moeschler, Sarah; Locher, Samira; Conzelmann, Karl-Klaus; Krämer, Beate; Zimmer, Gert

    2016-09-16

    Rabies is a highly fatal zoonotic disease which is primarily caused by rabies virus (RABV) although other members of the genus Lyssavirus can cause rabies as well. As yet, 14 serologically and genetically diverse lyssaviruses have been identified, mostly in bats. To assess the quality of rabies vaccines and immunoglobulin preparations, virus neutralization tests with live RABV are performed in accordance with enhanced biosafety standards. In the present work, a novel neutralization test is presented which takes advantage of a modified vesicular stomatitis virus (VSV) from which the glycoprotein G gene has been deleted and replaced by reporter genes. This single-cycle virus was trans-complemented with RABV envelope glycoprotein. Neutralization of this pseudotype virus with RABV reference serum or immune sera from vaccinated mice showed a strong correlation with the rapid fluorescent focus inhibition test (RFFIT). Importantly, pseudotype viruses containing the envelope glycoproteins of other lyssaviruses were neutralized by reference serum to a significantly lesser extent or were not neutralized at all. Taken together, a pseudotype virus system has been successfully developed which allows the safe, fast, and sensitive detection of neutralizing antibodies directed against different lyssaviruses.

  7. Structure of an antibody in complex with its mucin domain linear epitope that is protective against Ebola virus.

    Science.gov (United States)

    Olal, Daniel; Kuehne, Ana I; Bale, Shridhar; Halfmann, Peter; Hashiguchi, Takao; Fusco, Marnie L; Lee, Jeffrey E; King, Liam B; Kawaoka, Yoshihiro; Dye, John M; Saphire, Erica Ollmann

    2012-03-01

    Antibody 14G7 is protective against lethal Ebola virus challenge and recognizes a distinct linear epitope in the prominent mucin-like domain of the Ebola virus glycoprotein GP. The structure of 14G7 in complex with its linear peptide epitope has now been determined to 2.8 Å. The structure shows that this GP sequence forms a tandem β-hairpin structure that binds deeply into a cleft in the antibody-combining site. A key threonine at the apex of one turn is critical for antibody interaction and is conserved among all Ebola viruses. This work provides further insight into the mechanism of protection by antibodies that target the protruding, highly accessible mucin-like domain of Ebola virus and the structural framework for understanding and characterizing candidate immunotherapeutics.

  8. Radioimmunoassay and characterization of woodchuck hepatitis virus core antigen and antibody

    Energy Technology Data Exchange (ETDEWEB)

    Ponzetto, A; Cote, P J; Ford, E C; Engle, R; Gerin, J L; Cicmanec, J; Shapiro, M; Purcell, R H

    1985-06-01

    Solid-phase radioimmunoassays for woodchuck hepatitis virus core antigen (WHcAg) and antibody (anti-WHc) were developed. WHcAg in woodchuck liver homogenates was characterized by ultracentrifugation in CsCl gradients; both heavy and light cores were obtained from the liver of an animal during acute WHV infection, which is consistent with observations in hepatitis B virus infection in man. Endpoint titers of anti-WHc were higher in chronic WHV carriers than in animals recovered from acute infections. Both IgM and IgG anti-WHc antibodies were produced by infected woodchucks. A survey of colony woodchucks demonstrated that 88/89 animals having one or more markers of past or ongoing WHV infection were positive for anti-WHc. Thus, serum anti-WHc appears to be a sensitive marker of WHV infection.

  9. Antibody quality and protection from lethal Ebola virus challenge in nonhuman primates immunized with rabies virus based bivalent vaccine.

    Science.gov (United States)

    Blaney, Joseph E; Marzi, Andrea; Willet, Mallory; Papaneri, Amy B; Wirblich, Christoph; Feldmann, Friederike; Holbrook, Michael; Jahrling, Peter; Feldmann, Heinz; Schnell, Matthias J

    2013-01-01

    We have previously described the generation of a novel Ebola virus (EBOV) vaccine platform based on (a) replication-competent rabies virus (RABV), (b) replication-deficient RABV, or (c) chemically inactivated RABV expressing EBOV glycoprotein (GP). Mouse studies demonstrated safety, immunogenicity, and protective efficacy of these live or inactivated RABV/EBOV vaccines. Here, we evaluated these vaccines in nonhuman primates. Our results indicate that all three vaccines do induce potent immune responses against both RABV and EBOV, while the protection of immunized animals against EBOV was largely dependent on the quality of humoral immune response against EBOV GP. We also determined if the induced antibodies against EBOV GP differ in their target, affinity, or the isotype. Our results show that IgG1-biased humoral responses as well as high levels of GP-specific antibodies were beneficial for the control of EBOV infection after immunization. These results further support the concept that a successful EBOV vaccine needs to induce strong antibodies against EBOV. We also showed that a dual vaccine against RABV and filoviruses is achievable; therefore addressing concerns for the marketability of this urgently needed vaccine.

  10. Antibody quality and protection from lethal Ebola virus challenge in nonhuman primates immunized with rabies virus based bivalent vaccine.

    Directory of Open Access Journals (Sweden)

    Joseph E Blaney

    Full Text Available We have previously described the generation of a novel Ebola virus (EBOV vaccine platform based on (a replication-competent rabies virus (RABV, (b replication-deficient RABV, or (c chemically inactivated RABV expressing EBOV glycoprotein (GP. Mouse studies demonstrated safety, immunogenicity, and protective efficacy of these live or inactivated RABV/EBOV vaccines. Here, we evaluated these vaccines in nonhuman primates. Our results indicate that all three vaccines do induce potent immune responses against both RABV and EBOV, while the protection of immunized animals against EBOV was largely dependent on the quality of humoral immune response against EBOV GP. We also determined if the induced antibodies against EBOV GP differ in their target, affinity, or the isotype. Our results show that IgG1-biased humoral responses as well as high levels of GP-specific antibodies were beneficial for the control of EBOV infection after immunization. These results further support the concept that a successful EBOV vaccine needs to induce strong antibodies against EBOV. We also showed that a dual vaccine against RABV and filoviruses is achievable; therefore addressing concerns for the marketability of this urgently needed vaccine.

  11. Isotypes of Epstein-Barr virus antibodies in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Westergaard, Marie Wulff; Draborg, Anette Holck; Troelsen, Lone

    2015-01-01

    In order to study the humoral immune response against Epstein-Barr virus (EBV) in patients with rheumatoid arthritis (RA) and to compare it with the two major autoantibody types in RA, plasma samples from 77 RA patients, 28 patients with systemic lupus erythematosus (SLE), and 28 healthy controls...... and percentages of positives of IgG/IgA/IgM against the early lytic EBV antigen diffuse (EAD) were also found in RA patients compared to HCs but were highest in SLE patients. Furthermore, associations between the elevated EBNA-1 IgA and EBNA-1 IgM levels and the presence of IgM and IgA rheumatoid factors (RFs...

  12. Antibody Prophylaxis Against Dengue Virus 2 Infection in Non-Human Primates.

    Science.gov (United States)

    Simmons, Monika; Putnak, Robert; Sun, Peifang; Burgess, Timothy; Marasco, Wayne A

    2016-11-02

    Passive immunization with anti-dengue virus (DENV) immune serum globulin (ISG) or monoclonal antibodies (Mabs) may serve to supplement or replace vaccination for short-term dengue immune prophylaxis. In the present study, we sought to establish proof-of-concept by evaluating several DENV-neutralizing antibodies for their ability to protect rhesus macaques against viremia following live virus challenge, including human anti-dengue ISG, and a human Mab (Mab11/wt) and its genetically engineered variant (Mab11/mutFc) that is unable to bind to cells with Fc gamma receptors (FcγR) and potentiate antibody-dependent enhancement (ADE). In the first experiment, groups of animals received ISG or Mab11/wt at low doses (3-10 mg/kg) or a saline control followed by challenge with DENV-2 at day 10 or 30. After passive immunization, only low-titered circulating virus-neutralizing antibody titers were measured in both groups, which were undetectable by day 30. After challenge at day 10, a reduction in viremia duration compared with the control was seen only in the ISG group (75%). However, after a day 30 challenge, no reduction in viremia was observed in both immunized groups. In a second experiment to test the effect of higher antibody doses on short-term protection, groups received either ISG, Mab11/wt, Mab11/mutFc (each at 25 mg/kg) or saline followed by challenge with DENV-2 on day 10. Increased virus-neutralizing antibody titers were detected in all groups at day 5 postinjection, with geometric mean titers (GMTs) of 464 (ISG), 313 (Mab11/wt), and 309 (Mab11/mutFc). After challenge, there was complete protection against viremia in the group that received ISG, and a reduction in viremia duration of 89% and 83% in groups that received Mab11/wt and Mab11/mutFc, respectively. An in vitro ADE assay in Fcγ receptor-bearing K562 cells with sera collected immediately before challenge showed increased DENV-2 infection levels in the presence of both ISG and Mab11/wt, which peaked at a

  13. Monitoring of Antibodies Titre Against Canine Distemper Virus in Ferrets Vaccinated with a Live Modified Vaccine

    OpenAIRE

    L. Pavlačík; V. Celer, Jr.; V. Kajerová; V. Jekl; Z. Knotek; I. Literák

    2007-01-01

    A group of five ferrets vaccinated against the canine distemper virus (CDV) was evaluated as to the onset of anti-CDV antibody production and the serum levels of the animals were monitored for one year. The ferrets were immunized with a live attenuated vaccine. The vaccination pattern was as follows: primary vaccination at the age of 6 weeks, fi rst revaccination at 30 days after primary vaccination, and second revaccination after another 30 days. Blood samples were taken prior to primary vac...

  14. Acute hepatitis due to Epstein–Barr virus with cross-reacting antibodies to cytomegalovirus

    Directory of Open Access Journals (Sweden)

    Asli Karadeniz

    2018-01-01

    Full Text Available Epstein–Barr virus (EBV is the cause of systemic infection known as infectious mononucleosis with classic presentation of fever, oropharyngitis and lymphadenitis. EBV rarely causes acute hepatitis. In this report, we present a 19-year-old patient presented with nausea, fatigue and jaundice. Her physical examination and laboratory tests revealed the diagnosis as acute hepatitis due to EBV with cross-reacting antibodies to cytomegalovirus.

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

    DEFF Research Database (Denmark)

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

    2011-01-01

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

  16. Evaluation of five hepatitis delta virus marker assays for detection of antigen and antibody.

    OpenAIRE

    Bezeaud, A; Rosenswajg, M; Guillin, M C

    1989-01-01

    Five commercially available assays for hepatitis delta (HD) virus markers were compared for sensitivity, specificity, and reproducibility: three assays for antibody (anti-HD), provided by Diagnostics Pasteur, Organon Teknika, and Abbott Laboratories, and two assays for antigen (HD Ag), from Pasteur and Organon Teknika. The assay from Organon Teknika is the less sensitive assay for anti-HD detection. Although the sensitivities of the Pasteur and Abbott assays for anti-HD detection are similar,...

  17. Mechanism of Binding to Ebola Virus Glycoprotein by the ZMapp, ZMAb, and MB-003 Cocktail Antibodies

    OpenAIRE

    Davidson, Edgar; Bryan, Christopher; Fong, Rachel H.; Barnes, Trevor; Pfaff, Jennifer M.; Mabila, Manu; Rucker, Joseph B.; Doranz, Benjamin J.

    2015-01-01

    Cocktails of monoclonal antibodies (MAbs) that target the surface glycoprotein (GP) of Ebola virus (EBOV) are effective in nonhuman primate models and have been used under emergency compassionate-treatment protocols in human patients. However, the amino acids that form the detailed binding epitopes for the MAbs in the ZMapp, ZMAb, and the related MB-003 cocktails have yet to be identified. Other binding properties that define how each MAb functionally interacts with GP—such as affinity, epito...

  18. Prodduction of clone secretor of antibodies (IgG againt of infection bursal disease virus

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    Sandra Yuliet Marín

    2015-06-01

    Full Text Available ABSTRACT. Marín S.Y., dos Santos B.M., Patarroyo J.H. & Vargas M.I. [Prodduction of clone secretor of antibodies (IgG againt of infection bursal disease virus.] Produção de clones secretores de anticorpos (IgG contra o vírus da doença infecciosa bursal. Revista Brasileira de Medicina Veterinária, 37(2:238-144, 2015. Programa de Pós-Graduação em Medicina Veterinária, Universidade Federal de Viçosa, Avenida PH Rolfs, s/n, Viçosa, MG 36570- 000, Brasil. E-mail: bmsantos@ufv.br Three clones secreting of antibodies (Abs IgG against infection bursal disease virus IBDV was development. The IBDV was strain S706 (the intermediate vaccine was replicated in VERO cell and purified by sucrose gradient, for ELISA and mice inoculation. For the immunization of the mice BALB/c using as a saponin adjuvant, that allowed an inflammation reaction which enhanced the antibody response, detectable by ELISA. The fusion of splenic cells of the immunized mice and the mieloma SP2/0 resulted in 2 hybridoma families (2H11 and 5C7. After cloning by limiting dilution, 3 clones secretors of Abs from IgG class were obtained. The 3 obtained Abs were capable to reveal the proteins turn VPX and VP2 by “western blotting”, respectively of 47 kDa and 41 kDa. The definition of the isotypes recognized by obtained Abs must be object of characterization to allow the use of the antibodies in immunodiagnostic tests such as immunofluorescence, immunocitochemistry or capture ELISA, for epidemiologic of the disease researches or to differentiate vaccine’s virus of the field virus.

  19. Antibody Recognition of the Dengue Virus Proteome and Implications for Development of Vaccines

    Science.gov (United States)

    2011-04-01

    Parvovirus B19 empty capsids as antigen carriers for presentation of antigenic detenninants of dengue 2 virus. J. Infect. Dis. 194:790-794. 3... reactiv - ity against other DENV serotypes (1, 35). In contrast to DF, dengue hemorrhagic fever (DHF) is an infrequent but far more serious consequence of...recipients of the tetrava- lent DENV vaccine or from dengue cases owing to antibody cross- reactivity among serotypes (29). Furthermore, as results from

  20. PRODUCTION OF POLYCLONAL ANTIBODY TO THE COAT PROTEIN OF CITRUS TRISTEZA VIRUS IN CHICKEN EGGS

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    Nurhadi Nurhadi

    2016-10-01

    Full Text Available Citrus tristeza virus (CTV is one of the most destructive diseases in many citrus growing areas of Indonesia. Effective strategies for controlling CTV depend on diagnostic procedure namely enzyme-linked immunosorbent assay (ELISA. Study aimed to purify the CTV antigen and produced its polyclonal antibody. Virion of the severe CTV isolate designated UPM/ T-002 was concentrated by polyethylene glycol (PEG precipitation combined with low speed centrifugation. Semipurified antigen was further purified by sodium dodecyl sulphatepolyacrylamide gel electrophoresis (SDS-PAGE. The specific coat protein (CP band of CTV with molecular weight of 25 kD was excised and eluted using elution buffer containing 0.25 M Tris-HCl pH 6.8 + 0.1% SDS, then used as antigen for injection into 6-month-old female of White Leghorn chicken. Results, showed than the specific polyclonal antibody raised against the 25-kDa CP had a titer of approximately 104, gave low background reaction with healthy plant sap and reacted specifically with CTV isolates. The reaction was equally strong for a severe, a moderate, a mild, and a symptomless isolate, suggesting a broad reaction range of this antibody toward different CTV isolates. Optimal virus titer can be obtained since virus loss during purification could be minimized and the highly purified antigen as an immunogen could be obtained by cutting out the CP band from SDS-PAGE gels. Large amount of highly titer of CTV antibody can be produced in chicken egg. The simplicity of the procedure makes it economically acceptable and technically adoptable because the antibody can be produced in basic laboratory.

  1. Potent neutralization of influenza A virus by a single-domain antibody blocking M2 ion channel protein.

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    Guowei Wei

    Full Text Available Influenza A virus poses serious health threat to humans. Neutralizing antibodies against the highly conserved M2 ion channel is thought to offer broad protection against influenza A viruses. Here, we screened synthetic Camel single-domain antibody (VHH libraries against native M2 ion channel protein. One of the isolated VHHs, M2-7A, specifically bound to M2-expressed cell membrane as well as influenza A virion, inhibited replication of both amantadine-sensitive and resistant influenza A viruses in vitro, and protected mice from a lethal influenza virus challenge. Moreover, M2-7A showed blocking activity for proton influx through M2 ion channel. These pieces of evidence collectively demonstrate for the first time that a neutralizing antibody against M2 with broad specificity is achievable, and M2-7A may have potential for cross protection against a number of variants and subtypes of influenza A viruses.

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

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    Séverine Mercier-Delarue

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

  3. Application of xenogeneic anti-canine distemper virus antibodies in treatment of canine distemper puppies.

    Science.gov (United States)

    Liu, P C; Chen, C A; Chen, C M; Yen, C H; Lee, M H; Chuang, C K; Tu, C F; Su, B L

    2016-11-01

    The clinical feasibility of passive immunotherapy has not been demonstrated in dogs naturally infected with canine distemper. In this study, porcine anti-canine distemper virus IgG and F(ab') 2 antibody fragments were used to treat infected puppies. A total of 41 naturally infected puppies (age Äsix months) exhibiting severe respiratory signs, but lacking neurological signs, were enrolled in the study. Twenty-five puppies were treated with a combination of IgG or F(ab') 2 antibody fragments (Group 1) and supportive therapy and 16 puppies received routine supportive care only (Group 2). The survival rate of dogs in Group 1 (19/25; 76%) was significantly higher than that in Group 2 (5/16; 31·3%) (Pdistemper virus antibodies improved survival in puppies affected with canine distemper with minimal adverse effects. Therefore, this therapy could be considered for treatment of endangered animal species infected with canine distemper virus. © 2016 British Small Animal Veterinary Association.

  4. Specific antibodies to detect Tamarillo leaf malformation virus (TALMV) in Tamarillo

    International Nuclear Information System (INIS)

    Gallo Garcia, Yuliana; Marin Montoya, Mauricio; Gutierrez, Pablo Andres

    2011-01-01

    In Colombia, yields of Tamarillo are seriously affected by a complex viral disease known as virosis. This pathology was first reported in 1991 in the north of Antioquia and currently affects all Tamarillo growing regions in the country. Recent works have demonstrated the association of two potyviruses (potyviridae) with this disease: potato virus y (PVY) and Tamarillo leaf malformation virus (TALMV, proposed species). Specific diagnostic tools are required for early asymptomatic detection of these viruses and Tamarillo certification programs. In this study, we report the obtention of TALMV specific antibodies using a 15 residues peptide mimicking the n-terminal coat protein. Specificity and sensitivity of the anti-TALMV antibodies was determined by Elisa and dot-blot using recombinant protein and synthetic peptides as controls. The usefulness of these antibodies was validated from a preliminary trial of TALMV detection in plant samples obtained from Tamarillo crops in eastern Antioquia and results were compared with a TALMV specific coat RT-PCR detection protocol.

  5. Prevalence of antibodies to Japanese encephalitis virus among pigs in Bali and East Java, Indonesia, 2008.

    Science.gov (United States)

    Yamanaka, Atsushi; Mulyatno, Kris Cahyo; Susilowati, Helen; Hendrianto, Eryk; Utsumi, Takako; Amin, Mochamad; Lusida, Maria Inge; Soegijanto, Soegeng; Konishi, Eiji

    2010-01-01

    Japanese encephalitis virus (JEV) is a fatal disease in Asia. Pigs are considered to be the effective amplifying host for JEV in the peridomestic environment. Bali Island and Java Island in Indonesia provide a model to assess the effect of pigs on JEV transmission, since the pig density is nearly 100-fold higher in Bali than Java, while the geographic and climatologic environments are equivalent in these areas. We surveyed antibodies to JEV among 123 pigs in Mengwi (Bali) and 96 pigs in Tulungagung (East Java) in 2008 by the hemagglutination-inhibition (HAI) test. Overall prevalences were 49% in Bali and 6% in Java, with a significant difference between them (P Java. In addition, 2-mercaptoethanol-sensitive antibodies were found only from Bali samples. Further, the average HAI antibody titer obtained from positive samples was significantly higher in Bali (1:52) than Java (1:10; P Java.

  6. [A double antibody sandwich ELISA based assay for titration of severe fever with thrombocytopenia syndrome virus].

    Science.gov (United States)

    Liu, Lin; Zhang, Quan-Fu; Li, Chuan; Li, Jian-Dong; Jiang, Xiao-Lin; Zhang, Fu-Shun; Wu, Wei; Liang, Mi-Fang; Li, De-Xin

    2013-06-01

    To develop an assay for titration of severe fever with thrombocytopenia syndrome virus (SFTSV) based on double antibody sandwich ELISA. A double antibody sandwich ELISA was developed for detection of SFTSV based on SFTSV nucleocapsid (N) protein specific poly- and monoclonal antibodies, procedures were optimized and evaluated. This ELISA based titration assay was compared with fluorescence assasy and plaque assay based titration method. The results suggested that the titers obtained by ELISA based method are consistent with those obtained by IFA based method (R = 0.999) and the plaque assay titration method (R = 0.949). The novel ELISA based titration method with high sensitivity and specificity is easy to manage and perform, and can overcome the subjectivity associated with result determination of the fluorescence assay and plaque assay based methods. The novel ELISA based titration method can also be applied to high throughput detection.

  7. Hepatitis C virus infection can mimic type 1 (antinuclear antibody positive) autoimmune chronic active hepatitis.

    Science.gov (United States)

    Pawlotsky, J M; Deforges, L; Bretagne, S; André, C; Métreau, J M; Thiers, V; Zafrani, E S; Goossens, M; Duval, J; Mavier, J P

    1993-01-01

    Hepatitis C virus (HCV) has been shown to induce anti-liver-kidney microsomal-1 (LKM1) antibody positive chronic active hepatitis, simulating type 2 autoimmune chronic active hepatitis. The cases of five patients presenting with features of type 1 (antinuclear antibody positive) autoimmune chronic active hepatitis and extrahepatic autoimmune manifestations, in whom immunosuppressive treatment had no effect on liver disease are presented. In these patients, HCV infection could be shown by the presence in serum of anti-HCV antibodies and HCV-RNA detected by polymerase chain reaction. These cases suggest the following: (a) chronic HCV infection can mimic type 1, as well as type 2, autoimmune chronic active hepatitis; (b) HCV infection might be systematically sought in patients presenting with features of type 1 autoimmune chronic active hepatitis, with special care in patients who are unresponsive to immunosuppressive treatment. Images Figure PMID:7686122

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

    Directory of Open Access Journals (Sweden)

    Heidi Edelgard Drummer

    2014-07-01

    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.

  9. Dengue virus infection-enhancing antibody activities against Indonesian strains in inhabitants of central Thailand.

    Science.gov (United States)

    Yamanaka, Atsushi; Oddgun, Duangjai; Chantawat, Nantarat; Okabayashi, Tamaki; Ramasoota, Pongrama; Churrotin, Siti; Kotaki, Tomohiro; Kameoka, Masanori; Soegijanto, Soegeng; Konishi, Eiji

    2016-04-01

    Dengue virus (DENV) infection-enhancing antibodies are a hypothetic factor to increase the dengue disease severity. In this study, we investigated the enhancing antibodies against Indonesian strains of DENV-1-4 in 50 healthy inhabitants of central Thailand (Bangkok and Uthai Thani). Indonesia and Thailand have seen the highest dengue incidence in Southeast Asia. The infection history of each subject was estimated by comparing his/her neutralizing antibody titers against prototype DENV-1-4 strains. To resolve the difficulty in obtaining foreign live viruses for use as assay antigens, we used a recombinant system to prepare single-round infectious dengue viral particles based on viral sequence information. Irrespective of the previously infecting serotype(s), most serum samples showed significantly higher enhancement titers against Indonesian DENV-2 strains than against Thai DENV-2 strains, whereas the opposite effect was observed for the DENV-3 strains. Equivalent enhancing activities were observed against both DENV-1 and DENV-4. These results suggest that the genotype has an impact on enhancing antibody activities against DENV-2 and DENV-3, because the predominant circulating genotypes of each serotype differ between Indonesia and Thailand. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  10. Tissue localization, shedding, virus carriage, antibody response, and aerosol transmission of porcine epidemic diarrhea virus (PEDV) following inoculation of 4 week-old feeder pigs

    Science.gov (United States)

    Porcine epidemic diarrhea virus (PEDV) emerged in the U.S. in April 2013 and caused significant losses to the swine industry. The purpose of this investigation was to determine tissue localization, shedding patterns, virus carriage, antibody response, and aerosol transmission of PEDV following inocu...

  11. Comparison of neutralizing and hemagglutination-inhibiting antibody responses to influenza A virus vaccination of human immunodeficiency virus-infected individuals

    NARCIS (Netherlands)

    Benne, CA; Harmsen, M; Tavares, L; Kraaijeveld, CA; De Jong, JC

    A neutralization enzyme immunoassay (N-EIA) was used to determine the neutralizing serum antibody titers to influenza A/Taiwan/1/86 (H1N1) and Beijing/353/89 (H3N2) viruses after vaccination of 51 human immunodeficiency virus (HIV) type 1-infected individuals and 10 healthy noninfected controls

  12. 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

    2007-01-01

    with VHS but with no clinical signs of infection. When the sera were examined by 50%PNT using the VHSV reference isolate DK-F1 or the heat attenuated DK-F25 mutant strain, no neutralizing antibodies were found. In contrast, when one of the virus isolates from the farm (homologous virus) was used in the 50...

  13. Lentivirus display: stable expression of human antibodies on the surface of human cells and virus particles.

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    Ran Taube

    Full Text Available BACKGROUND: Isolation of human antibodies using current display technologies can be limited by constraints on protein expression, folding and post-translational modifications. Here we describe a discovery platform that utilizes self-inactivating (SIN lentiviral vectors for the surface display of high-affinity single-chain variable region (scFv antibody fragments on human cells and lentivirus particles. METHODOLOGY/PRINCIPAL FINDINGS: Bivalent scFvFc human antibodies were fused in frame with different transmembrane (TM anchoring moieties to allow efficient high-level expression on human cells and the optimal TM was identified. The addition of an eight amino acid HIV-1 gp41 envelope incorporation motif further increased scFvFc expression on human cells and incorporation into lentiviral particles. Both antibody-displaying human cells and virus particles bound antigen specifically. Sulfation of CDR tyrosine residues, a property recently shown to broaden antibody binding affinity and antigen recognition was also demonstrated. High level scFvFc expression and stable integration was achieved in human cells following transduction with IRES containing bicistronic SIN lentivectors encoding ZsGreen when scFvFc fusion proteins were expressed from the first cassette. Up to 10(6-fold enrichment of antibody expressing cells was achieved with one round of antigen coupled magnetic bead pre-selection followed by FACS sorting. Finally, the scFvFc displaying human cells could be used directly in functional biological screens with remarkable sensitivity. CONCLUSIONS/SIGNIFICANCE: This antibody display platform will complement existing technologies by virtue of providing properties unique to lentiviruses and antibody expression in human cells, which, in turn, may aid the discovery of novel therapeutic human mAbs.

  14. Felix Hoppe-Seyler Lecture 1997. Protective antibody responses against viruses.

    Science.gov (United States)

    Zinkernagel, R M

    1997-08-01

    Neutralizing antibody responses against the acute cytopathic vesicular stomatitis virus (VSV) have been studied in mice to evaluate their general characteristics including specificity, self-/non-self discrimination and memory. IgM responses are generated very early, by day 3 to 4, in a T helper cell-independent fashion and without VSV having polyclonal activating capacities. The order of the glycoprotein tips on the virus envelope (multiple, 8-10 nm distance, paracrystalline) exhibiting the neutralizing determinants are key to this prompt response. These paracrystalline identical multimeric antigens are characteristic of infectious agents and are always reacted against by B cells. Self-antigens that are accessible to B cells in the intact host are either monomeric in serum or mobile multimers on cell surfaces; these configurations need contact dependent or contact independent T help, respectively. Because T help is tolerant against self-antigens, no anti-self B cell responses are usually induced against monomeric self-antigens. If collagen or DNA (rigid multimeric self-antigens) become accessible, however, they may become targets of auto-antibody responses. The antibody repertoire against VSV is partially contained in the germline and partially is generated by somatic mutation; they seem not to undergo affinity-maturation. In any case protection against lethal infection is dependent upon strictly T helper cell dependent IgG generated by day 6 to 7 and reaches a protective level of about 1-10 micrograms/ml. Interesting affinity/avidity and onrate above a minimal threshold are of no apparent advantage for protection in vivo. Maintenance of these antibody levels by antigen depots, and not the presence of memory B cells alone, is key to providing protective immunological memory. Collectively these data suggest that studying biologically important protective antibody responses may modify some of the parameters that have been defined by studying hapten specific antibody

  15. Seroprevalence of antibodies against chikungunya virus in Singapore resident adult population.

    Science.gov (United States)

    Ang, Li Wei; Kam, Yiu Wing; Lin, Cui; Krishnan, Prabha Unny; Tay, Joanne; Ng, Lee Ching; James, Lyn; Lee, Vernon J M; Goh, Kee Tai; Ng, Lisa F P; Lin, Raymond T P

    2017-12-01

    We determined the seroprevalence of chikungunya virus (CHIKV) infection in the adult resident population in Singapore following local outbreaks of chikungunya fever (CHIKF) in 2008-2009. Our cross-sectional study involved residual sera from 3,293 adults aged 18-79 years who had participated in the National Health Survey in 2010. Sera were tested for IgG antibodies against CHIKV and dengue virus (DENV) and neutralizing antibodies against CHIKV. The prevalence of CHIKV-neutralizing antibodies among Singapore residents aged 18-79 years was 1.9% (95% confidence interval: 1.4%- 2.3%). The CHIKV seroprevalence was highest in the elderly aged 70-79 years at 11.5%, followed by those aged 30-39 years at 3.1%. Men had significantly higher CHIKV seroprevalence than women (2.5% versus 1.3%, p = 0.01). Among the three main ethnic groups, Indians had the highest seroprevalence (3.5%) compared to Chinese (1.6%) and Malays (0.7%) (p = 0.02 and p = 0.01, respectively). Multivariable logistic regression identified adults aged 30-39 years and 70-79 years, men, those of Indian ethnicity and ethnic minority groups, and residence on ground floor of public and private housing apartments as factors that were significantly associated with a higher likelihood of exposure to CHIKV. The overall prevalence of anti-DENV IgG antibodies was 56.8% (95% CI: 55.1%- 58.5%), while 1.5% (95% CI: 1.1%- 2.0%) of adults possessed both neutralizing antibodies against CHIKV and IgG antibodies against DENV. Singapore remains highly susceptible to CHIKV infection. There is a need to maintain a high degree of vigilance through disease surveillance and vector control. Findings from such serological study, when conducted on a regular periodic basis, could supplement surveillance to provide insights on CHIKV circulation in at-risk population.

  16. Inhibition of human immunodeficiency virus (HIV) infection in vitro by anticarbohydrate monoclonal antibodies: peripheral glycosylation of HIV envelope glycoprotein gp120 may be a target for virus neutralization

    DEFF Research Database (Denmark)

    Hansen, J E; Clausen, H; Nielsen, C

    1990-01-01

    Carbohydrate structures are often involved in the initial adhesion of pathogens to target cells. In the present study, a panel of anticarbohydrate monoclonal antibodies (MAbs) was tested for their ability to inhibit in vitro human immunodeficiency virus infectivity. MAbs against three different N......- and O-linked carbohydrate epitopes (LeY, A1, and sialyl-Tn) were able to block infection by cell-free virus as well as inhibit syncytium formation. Inhibition of virus infectivity was independent of virus strain (HTLVIIIB or patient isolate SSI-002), the cell line used for virus propagation (H9 or MT4...

  17. Gag- and env-specific serum antibodies in cats after natural and experimental infection with feline immunodeficiency virus.

    NARCIS (Netherlands)

    G.F. Rimmelzwaan (Guus); C.H.J. Siebelink (Kees); H. Broos; G.A. Drost; K. Weijer (Kees); R. van Herwijnen (Rob); A.D.M.E. Osterhaus (Albert)

    1994-01-01

    textabstractIn order to monitor the antibody response to feline immunodeficiency virus (FIV) in cats, following experimental and natural infection, enzyme-linked immunosorbent assays (ELISAs) were developed using recombinant env and gag proteins and p24-specific monoclonal antibodies. It was shown

  18. Validation of the rapid fluorescent focus inhibition test for rabies virus-neutralizing antibodies in clinical samples

    NARCIS (Netherlands)

    Kostense, Stefan; Moore, Susan; Companjen, Arjen; Bakker, Alexander B. H.; Marissen, Wilfred E.; von Eyben, Rie; Weverling, Gerrit Jan; Hanlon, Cathleen; Goudsmit, Jaap

    2012-01-01

    Monoclonal antibodies are successful biologics in treating a variety of diseases, including the prevention or treatment of viral infections. CL184 is a 1:1 combination of two human monoclonal IgG1 antibodies (CR57 and CR4098) against rabies virus, produced in the PER.C6 human cell line. The two

  19. Stoichiometry of monoclonal antibody neutralization of T-cell line-adapted human immunodeficiency virus type 1

    DEFF Research Database (Denmark)

    Schønning, Kristian; Lund, O; Lund, O S

    1999-01-01

    In order to study the stoichiometry of monoclonal antibody (MAb) neutralization of T-cell line-adapted human immunodeficiency virus type 1 (HIV-1) in antibody excess and under equilibrium conditions, we exploited the ability of HIV-1 to generate mixed oligomers when different env genes...

  20. Neutralizing monoclonal antibodies against hepatitis C virus E2 protein bind discontinuous epitopes and inhibit infection at a postattachment step

    DEFF Research Database (Denmark)

    Sabo, Michelle C; Luca, Vincent C; Prentoe, Jannick

    2011-01-01

    The E2 glycoprotein of hepatitis C virus (HCV) mediates viral attachment and entry into target hepatocytes and elicits neutralizing antibodies in infected patients. To characterize the structural and functional basis of HCV neutralization, we generated a novel panel of 78 monoclonal antibodies (M...

  1. Cooperativity between CD8+ T cells, non-neutralizing antibodies, and alveolar macrophages is important for heterosubtypic influenza virus immunity.

    Directory of Open Access Journals (Sweden)

    Brian J Laidlaw

    2013-03-01

    Full Text Available Seasonal epidemics of influenza virus result in ∼36,000 deaths annually in the United States. Current vaccines against influenza virus elicit an antibody response specific for the envelope glycoproteins. However, high mutation rates result in the emergence of new viral serotypes, which elude neutralization by preexisting antibodies. T lymphocytes have been reported to be capable of mediating heterosubtypic protection through recognition of internal, more conserved, influenza virus proteins. Here, we demonstrate using a recombinant influenza virus expressing the LCMV GP33-41 epitope that influenza virus-specific CD8+ T cells and virus-specific non-neutralizing antibodies each are relatively ineffective at conferring heterosubtypic protective immunity alone. However, when combined virus-specific CD8 T cells and non-neutralizing antibodies cooperatively elicit robust protective immunity. This synergistic improvement in protective immunity is dependent, at least in part, on alveolar macrophages and/or other lung phagocytes. Overall, our studies suggest that an influenza vaccine capable of eliciting both CD8+ T cells and antibodies specific for highly conserved influenza proteins may be able to provide heterosubtypic protection in humans, and act as the basis for a potential "universal" vaccine.

  2. Effective surveillance for early classical swine fever virus detection will utilize both virus and antibody detection capabilities.

    Science.gov (United States)

    Panyasing, Yaowalak; Kedkovid, Roongtham; Thanawongnuwech, Roongroje; Kittawornrat, Apisit; Ji, Ju; Giménez-Lirola, Luis; Zimmerman, Jeffrey

    2018-03-01

    Early recognition and rapid elimination of infected animals is key to controlling incursions of classical swine fever virus (CSFV). In this study, the diagnostic characteristics of 10 CSFV assays were evaluated using individual serum (n = 601) and/or oral fluid (n = 1417) samples collected from -14 to 28 days post inoculation (DPI). Serum samples were assayed by virus isolation (VI), 2 commercial antigen-capture enzyme-linked immunosorbent assays (ELISA), virus neutralization (VN), and 3 antibody ELISAs. Both serum and oral fluid samples were tested with 3 commercial real-time reverse transcription-polymerase chain reaction (rRT-PCR) assays. One or more serum samples was positive by VI from DPIs 3 to 21 and by antigen-capture ELISAs from DPIs 6 to 17. VN-positive serum samples were observed at DPIs ≥ 7 and by antibody ELISAs at DPIs ≥ 10. CSFV RNA was detected in serum samples from DPIs 2 to 28 and in oral fluid samples from DPIs 4 to 28. Significant differences in assay performance were detected, but most importantly, no single combination of sample and assay was able to dependably identify CSFV-inoculated pigs throughout the 4-week course of the study. The results show that effective surveillance for CSFV, especially low virulence strains, will require the use of PCR-based assays for the detection of early infections (<14 days) and antibody-based assays, thereafter. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. H9N2 avian influenza virus antibody titers in human population in fars province, Iran

    Directory of Open Access Journals (Sweden)

    MM Hadipour

    2010-09-01

    Full Text Available Among the avian influenza A virus subtypes, H5N1 and H9N2 viruses have the potential to cause an influenza pandemic because they are widely prevalent in avian species in Asia and have demonstrated the ability to infect humans. This study was carried out to determined the seroprevalence of H9N2 avian influenza virus in different human populations in Fars province, which is situated in the south of Iran. Antibodies against H9N2 avian influenza virus were measured using hemagglutination-inhibition (HI test in sera from 300 individuals in five different population in Fars province, including poultry-farm workers, slaughter-house workers, veterinarians, patients with clinical signs of respiratory disease, and clinically normal individuals, who were not or rarely in contact with poultry. Mean antibody titers of 7.3, 6.8, 6.1, 4.5, and 2.9 and seroprevalences of 87%, 76.2%, 72.5%, 35.6%, and 23% were determined in those groups, respectively. Higher prevalences were detected in poultry-farm workers, slaughter-house workers, and veterinarians, possibly due to their close and frequent contact with poultry.

  4. SURVEILLANCE FOR ANTIBODIES AGAINST SIX CANINE VIRUSES IN WILD RACCOONS (PROCYON LOTOR) IN JAPAN.

    Science.gov (United States)

    Aoki, Emiko; Soma, Takehisa; Yokoyama, Mayumi; Matsubayashi, Makoto; Sasai, Kazumi

    2017-10-01

    Raccoons (Procyon lotor) are found worldwide. They are frequently seen in crowded inner cities as well as in forests or wooded areas, often living in proximity to humans and their pets. We examined sera from 100 wild raccoons in Japan for antibodies to six canine viruses with veterinary significance to assess their potential as reservoirs. We also aimed to understand the distribution of potentially infected wildlife. We found that 7% of samples were seropositive for canine distemper virus (CDV), 10% for canine parvovirus type 2, 2% for canine adenovirus type 1, 6% for canine adenovirus type 2, and 7% for canine coronavirus. No samples were found to be seropositive for canine parainfluenza virus. Seropositivity rates for canine distemper virus and canine parvovirus type 2 were significantly different between areas, and younger raccoons (Canis lupus familiaris), our results suggest that they can act as reservoirs for some of these important canine viruses and might be involved in viral transmission. Further study should include isolation and analysis of canine viruses in wild raccoons from a wider area.

  5. Influenza virus neutralizing antibodies and IgG isotype profiles after immunization of mice with influenza A subunit vaccine using various adjuvants

    NARCIS (Netherlands)

    Benne, CA; Harmsen, M; vanderGraaff, W; Verheul, AFM; Snippe, H; Kraaijeveld, CA

    The influence of various adjuvants on the development of influenza virus neutralizing antibodies and distribution of anti-influenza virus IgG isotypes after immunization of mice with influenza A (H3N2) subunit vaccine was investigated. Serum titres of influenza virus neutralizing antibodies and

  6. Low intrathecal antibody production despite high seroprevalence of Epstein-Barr virus in multiple sclerosis: a review of the literature.

    Science.gov (United States)

    Ruprecht, Klemens; Wildemann, Brigitte; Jarius, Sven

    2018-02-01

    Patients with multiple sclerosis (MS) frequently have an intrathecal production of antibodies to different common viruses, which can be detected by elevated antiviral antibody indices (AIs). There is a strong and consistent association of MS and Epstein-Barr virus (EBV) infection. To systematically compare the frequencies of intrathecal antibody production to EBV, measles virus, rubella virus, varicella zoster virus (VZV) and herpes simplex virus (HSV) in patients with MS. Review of the English and German literature on the frequencies of intrathecal immunoglobulin (Ig)G antibody production, as defined by an elevated AI, to EBV, measles virus, rubella virus, VZV and HSV in adult and pediatric patients with MS. In nine original studies identified, the frequencies of an intrathecal production of antibodies to Epstein-Barr nuclear antigen-1 (33/340, 9.7%), EBV viral capsid antigen (12/279, 4.3%) and antigens from EBV-infected cell lines (14/90, 15.6%) in adult patients with MS were clearly lower (p ≤ 0.03 for all pairwise comparisons) than the frequencies of an intrathecal production of antibodies to measles virus (612/922, 66.4%), rubella virus (521/922, 56.5%), VZV (470/922, 51%; data from 17 original studies) and HSV (78/291, 26.8%; data from 6 original studies). Though based on a lower number of original studies and patients, findings in children with MS were essentially similar. As in adults and children with MS the seroprevalence of EBV is higher than the seroprevalences of the other investigated viruses, the lower frequency of elevated EBV AIs became even more pronounced after correction of the frequencies of elevated antiviral AIs for the seroprevalences of the respective viruses. Given the very high seroprevalence of EBV in MS, the frequency of intrathecally produced antibodies to EBV in patients with MS is paradoxically low compared to that of other common viruses. These findings are compatible with the recently proposed hypothesis that in individuals

  7. Epitope Dampening Monotypic Measles Virus Hemagglutinin Glycoprotein Results in Resistance to Cocktail of Monoclonal Antibodies

    Science.gov (United States)

    Lech, Patrycja J.; Tobin, Gregory J.; Bushnell, Ruth; Gutschenritter, Emily; Pham, Linh D.; Nace, Rebecca; Verhoeyen, Els; Cosset, François-Loïc; Muller, Claude P.; Russell, Stephen J.; Nara, Peter L.

    2013-01-01

    The measles virus (MV) is serologically monotypic. Life-long immunity is conferred by a single attack of measles or following vaccination with the MV vaccine. This is contrary to viruses such as influenza, which readily develop resistance to the immune system and recur. A better understanding of factors that restrain MV to one serotype may allow us to predict if MV will remain monotypic in the future and influence the design of novel MV vaccines and therapeutics. MV hemagglutinin (H) glycoprotein, binds to cellular receptors and subsequently triggers the fusion (F) glycoprotein to fuse the virus into the cell. H is also the major target for neutralizing antibodies. To explore if MV remains monotypic due to a lack of plasticity of the H glycoprotein, we used the technology of Immune Dampening to generate viruses with rationally designed N-linked glycosylation sites and mutations in different epitopes and screened for viruses that escaped monoclonal antibodies (mAbs). We then combined rationally designed mutations with naturally selected mutations to generate a virus resistant to a cocktail of neutralizing mAbs targeting four different epitopes simultaneously. Two epitopes were protected by engineered N-linked glycosylations and two epitopes acquired escape mutations via two consecutive rounds of artificial selection in the presence of mAbs. Three of these epitopes were targeted by mAbs known to interfere with receptor binding. Results demonstrate that, within the epitopes analyzed, H can tolerate mutations in different residues and additional N-linked glycosylations to escape mAbs. Understanding the degree of change that H can tolerate is important as we follow its evolution in a host whose immunity is vaccine induced by genotype A strains instead of multiple genetically distinct wild-type MVs. PMID:23300970

  8. Novel rabies virus-neutralizing epitope recognized by human monoclonal antibody: Fine mapping and escape mutant analysis

    NARCIS (Netherlands)

    Marissen, W.E.; Kramer, R.A.; Rice, A.; Weldon, W.C.; Niezgoda, M.; Faber, M.; Slootstra, J.W.; Meloen, R.H.; Clijsters-van der Horst, M.; Visser, T.J.; Jongeneelen, M.; Thijsse, S.; Throsby, M.; Kruif, de J.; Rupprecht, C.E.; Dietzschold, B.; Goudsmit, J.; Bakker, A.B.H.

    2005-01-01

    Anti-rabies virus immunoglobulin combined with rabies vaccine protects humans from lethal rabies infections. For cost and safety reasons, replacement of the human or equine polyclonal immunoglobulin is advocated, and the use of rabies virus-specific monoclonal antibodies (MAbs) is recommended. We

  9. Novel rabies virus-neutralizing epitope recognized by human monoclonal antibody: fine mapping and escape mutant analysis

    NARCIS (Netherlands)

    Marissen, Wilfred E.; Kramer, R. Arjen; Rice, Amy; Weldon, William C.; Niezgoda, Michael; Faber, Milosz; Slootstra, Jerry W.; Meloen, Rob H.; Clijsters-van der Horst, Marieke; Visser, Therese J.; Jongeneelen, Mandy; Thijsse, Sandra; Throsby, Mark; de Kruif, John; Rupprecht, Charles E.; Dietzschold, Bernhard; Goudsmit, Jaap; Bakker, Alexander B. H.

    2005-01-01

    Anti-rabies virus immunoglobulin combined with rabies vaccine protects humans from lethal rabies infections. For cost and safety reasons, replacement of the human or equine polyclonal immunoglobulin is advocated, and the use of rabies virus-specific monoclonal antibodies (MAbs) is recommended. We

  10. Epitopes on the peplomer protein of infectious bronchitis virus strain M41 as defined by monoclonal antibodies.

    NARCIS (Netherlands)

    N.M.C. Bleumink-Pluym; A.D.M.E. Osterhaus (Albert); M.C. Horzinek; B.A.M. van der Zeijst (Ben); H.G.M. Niesters (Bert)

    1987-01-01

    textabstractSixteen monoclonal antibodies (Mcabs) were prepared against infectious bronchitis virus strain M41, all of them reacting with the peplomer protein. One of them, Mcab 13, was able to neutralize the virus and to inhibit hemagglutination. Competition binding assays allowed the definition of

  11. Cooperativity in virus neutralization by human monoclonal antibodies to two adjacent regions located at the amino terminus of hepatitis C virus E2 glycoprotein

    DEFF Research Database (Denmark)

    Keck, Zhenyong; Wang, Wenyan; Wang, Yong

    2013-01-01

    A challenge for hepatitis C virus (HCV) vaccine development is defining conserved epitopes that induce protective antibodies against this highly diverse virus. An envelope glycoprotein (E2) segment located at amino acids (aa) 412 to 423 contains highly conserved neutralizing epitopes. While...... at higher concentrations. However, the overall effect was additive neutralization. A similar pattern was observed when these antibodies were combined to block E2 binding to the HCV coreceptor, CD81. These findings demonstrate that both of these E2 regions participate in epitopes mediating virus...... (HCVcc) with various activities. Although nonneutralizing HC33 HMAbs were isolated, they had lower binding affinities than neutralizing HC33 HMAbs. These antibodies could be converted to neutralizing antibodies by affinity maturation. Unidirectional competition for binding to E2 was observed between HC33...

  12. Interplay of foot-and-mouth disease virus, antibodies and plasmacytoid dendritic cells: virus opsonization under non-neutralizing conditions results in enhanced interferon-alpha responses

    Directory of Open Access Journals (Sweden)

    Lannes Nils

    2012-08-01

    Full Text Available Abstract Foot-and-mouth disease virus (FMDV is a highly infectious member of the Picornaviridae inducing an acute disease of cloven-hoofed species. Vaccine-induced immune protection correlates with the presence of high levels of neutralizing antibodies but also opsonising antibodies have been proposed as an important mechanism of the immune response contributing to virus clearance by macrophages and leading to the production of type-I interferon (IFN by plasmacytoid dendritic cells (pDC. The present study demonstrates that the opsonising antibody titres mediating enhanced IFN-α responses in pDC were similar to neutralizing titres, when antigenically related viruses from the same serotype were employed. However, sera cross-reacted also with non-neutralized isolates of multiple serotypes, when tested in this assay. Both uncomplexed virus and immune complexed virus stimulated pDC via Toll-like receptor 7. An additional finding of potential importance for strain-specific differences in virulence and/or immunogenicity was that pDC activation by FMDV strongly differed between viral isolates. Altogether, our results indicate that opsonising antibodies can have a broader reactivity than neutralizing antibodies and may contribute to antiviral responses induced against antigenically distant viruses.

  13. Sero-prevalence of virus neutralizing antibodies for rabies in different groups of dogs following vaccination.

    Science.gov (United States)

    Pimburage, R M S; Gunatilake, M; Wimalaratne, O; Balasuriya, A; Perera, K A D N

    2017-05-18

    Mass vaccination of dogs is considered fundamental for national rabies control programmes in Sri Lanka, as dog is the main reservoir and transmitter of the disease. Dogs were followed to determine the sero-prevalence of antibodies to the rabies virus. Altogether 510 previously vaccinated and unvaccinated dogs with owners (domestic dogs) and dogs without owners (stray dogs) of the local guard dog breed in different age groups recruited from Kalutara District, Sri Lanka. The dogs were vaccinated with a monovalent inactivated vaccine intramuscularly and serum antibody titres on days 0, 30, 180 and 360 were determined by the Rapid Fluorescent Focus Inhibition Test (RFFIT). The results indicated, a single dose of anti-rabies vaccination fails to generate a protective level of immunity (0.5 IU/ml) which lasts until 1 year in 40.42% of dogs without owners and 57.14% of previously unvaccinated juvenile (age: 3 months to 1 year) dogs with owners. More than one vaccination would help to maintain antibody titres above the protective level in the majority of dogs. The pattern of antibody titre development in annually vaccinated and irregularly vaccinated (not annual) adult dogs with owners is closely similar irrespective of regularity in vaccination. Previously vaccinated animals have higher (2 IU/ml) antibody titres to begin with and have a higher antibody titre on day 360 too. They show a very good antibody titre by day 180. Unvaccinated animals start with low antibody titre and return to low titres by day 360, but have a satisfactory antibody titre by day 180. A single dose of anti-rabies vaccination is not sufficient for the maintenance of antibody titres for a period of 1 year in puppies, juvenile dogs with owners and in dogs without owners. Maternal antibodies do not provide adequate protection to puppies of previously vaccinated dams and puppies of previously unvaccinated dams. Immunity development after vaccination seems to be closely similar in both the groups

  14. A humanised murine monoclonal antibody protects mice from Venezuelan equine encephalitis virus, Everglades virus and Mucambo virus when administered up to 48 h after airborne challenge

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, Lyn M., E-mail: lmobrien@dstl.gov.uk; Goodchild, Sarah A.; Phillpotts, Robert J.; Perkins, Stuart D.

    2012-05-10

    Currently there are no licensed antiviral treatments for the Alphaviruses Venezuelan equine encephalitis virus (VEEV), Everglades virus and Mucambo virus. We previously developed a humanised version of the mouse monoclonal antibody 1A3B-7 (Hu1A3B-7) which exhibited a wide range of reactivity in vitro and was able to protect mice from infection with VEEV. Continued work with the humanised antibody has now demonstrated that it has the potential to be a new human therapeutic. Hu1A3B-7 successfully protected mice from infection with multiple Alphaviruses. The effectiveness of the humanisation process was determined by assessing proliferation responses in human T-cells to peptides derived from the murine and humanised versions of the V{sub H} and V{sub L} domains. This analysis showed that the number of human T-cell epitopes within the humanised antibody had been substantially reduced, indicating that Hu1A3B-7 may have reduced immunogenicity in vivo.

  15. Radioimmunoprecipitation and immunoblot studies of antibodies to rubella virus in patients with chronic liver disease

    International Nuclear Information System (INIS)

    Kalvenes, M.B.; Kalland, K.H.; Haukenes, G.

    1994-01-01

    Patients with autoimmune chronic active hepatitis (AICAH) and some other chronic liver disorders often have very high titres of rubella HI antibodies. In the present study sera from 46 patients with chronic liver disease and controls were examined for rubella antibodies using radioimmunoprecipitation assay (RIPA) and Western blot. RIPA appeared to be more suitable than Western blot for the study of the individual antibody specificities provided that proteins (possibly actin) interfering with the resolution of the E2 glycoprotein band are identified. It was shown that patients with high rubella HI titres reacted strongly against the E1 glycoprotein and in general also against the core protein (C). Reactivity to the E2 glycoprotein was detected with all sera from patients with chronic liver disease but varied more in strength. Three patients with post-acute rubella showed very faint E2 reactivity, but strong E1 and C reactivities. Patients with primary biliary cirrhosis had normal HI titres and showed no increase in reactivity in RIPA. The present findings show that patients with chronic liver disease and high rubella HI antibody titres exhibit an enhanced specific antibody response to rubella virus structural proteins. (authors)

  16. Structure of general-population antibody titer distributions to influenza A virus.

    Science.gov (United States)

    Nhat, Nguyen Thi Duy; Todd, Stacy; de Bruin, Erwin; Thao, Tran Thi Nhu; Vy, Nguyen Ha Thao; Quan, Tran Minh; Vinh, Dao Nguyen; van Beek, Janko; Anh, Pham Hong; Lam, Ha Minh; Hung, Nguyen Thanh; Thanh, Nguyen Thi Le; Huy, Huynh Le Anh; Ha, Vo Thi Hong; Baker, Stephen; Thwaites, Guy E; Lien, Nguyen Thi Nam; Hong, Tran Thi Kim; Farrar, Jeremy; Simmons, Cameron P; Chau, Nguyen Van Vinh; Koopmans, Marion; Boni, Maciej F

    2017-07-20

    Seroepidemiological studies aim to understand population-level exposure and immunity to infectious diseases. Their results are normally presented as binary outcomes describing the presence or absence of pathogen-specific antibody, despite the fact that many assays measure continuous quantities. A population's natural distribution of antibody titers to an endemic infectious disease may include information on multiple serological states - naiveté, recent infection, non-recent infection, childhood infection - depending on the disease in question and the acquisition and waning patterns of immunity. In this study, we investigate 20,152 general-population serum samples from southern Vietnam collected between 2009 and 2013 from which we report antibody titers to the influenza virus HA1 protein using a continuous titer measurement from a protein microarray assay. We describe the distributions of antibody titers to subtypes 2009 H1N1 and H3N2. Using a model selection approach to fit mixture distributions, we show that 2009 H1N1 antibody titers fall into four titer subgroups and that H3N2 titers fall into three subgroups. For H1N1, our interpretation is that the two highest-titer subgroups correspond to recent and historical infection, which is consistent with 2009 pandemic attack rates. Similar interpretations are available for H3N2, but right-censoring of titers makes these interpretations difficult to validate.

  17. Human monoclonal antibodies derived from a patient infected with 2009 pandemic influenza A virus broadly cross-neutralize group 1 influenza viruses

    International Nuclear Information System (INIS)

    Pan, Yang; Sasaki, Tadahiro; Kubota-Koketsu, Ritsuko; Inoue, Yuji; Yasugi, Mayo; Yamashita, Akifumi; Ramadhany, Ririn; Arai, Yasuha; Du, Anariwa; Boonsathorn, Naphatsawan; Ibrahim, Madiha S.

    2014-01-01

    Highlights: • Influenza infection can elicit heterosubtypic antibodies to group 1 influenza virus. • Three human monoclonal antibodies were generated from an H1N1-infected patient. • The antibodies predominantly recognized α-helical stem of viral hemagglutinin (HA). • The antibodies inhibited HA structural activation during the fusion process. • The antibodies are potential candidates for future antibody therapy to influenza. - Abstract: Influenza viruses are a continuous threat to human public health because of their ability to evolve rapidly through genetic drift and reassortment. Three human monoclonal antibodies (HuMAbs) were generated in this study, 1H11, 2H5 and 5G2, and they cross-neutralize a diverse range of group 1 influenza A viruses, including seasonal H1N1, 2009 pandemic H1N1 (H1N1pdm) and avian H5N1 and H9N2. The three HuMAbs were prepared by fusing peripheral blood lymphocytes from an H1N1pdm-infected patient with a newly developed fusion partner cell line, SPYMEG. All the HuMAbs had little hemagglutination inhibition activity but had strong membrane-fusion inhibition activity against influenza viruses. A protease digestion assay showed the HuMAbs targeted commonly a short α-helix region in the stalk of the hemagglutinin. Furthermore, Ile45Phe and Glu47Gly double substitutions in the α-helix region made the HA unrecognizable by the HuMAbs. These two amino acid residues are highly conserved in the HAs of H1N1, H5N1 and H9N2 viruses. The HuMAbs reported here may be potential candidates for the development of therapeutic antibodies against group 1 influenza viruses

  18. Human monoclonal antibodies derived from a patient infected with 2009 pandemic influenza A virus broadly cross-neutralize group 1 influenza viruses

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Yang [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Sasaki, Tadahiro [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); JST/JICA, Science and Technology Research Partnership for Sustainable Development (SATREPS), Tokyo (Japan); Kubota-Koketsu, Ritsuko [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Kanonji Institute, The Research Foundation for Microbial Diseases of Osaka University, Kanonji, Kagawa (Japan); JST/JICA, Science and Technology Research Partnership for Sustainable Development (SATREPS), Tokyo (Japan); Inoue, Yuji [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); JST/JICA, Science and Technology Research Partnership for Sustainable Development (SATREPS), Tokyo (Japan); Yasugi, Mayo [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka (Japan); JST/JICA, Science and Technology Research Partnership for Sustainable Development (SATREPS), Tokyo (Japan); Yamashita, Akifumi; Ramadhany, Ririn; Arai, Yasuha [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Du, Anariwa [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); JST/JICA, Science and Technology Research Partnership for Sustainable Development (SATREPS), Tokyo (Japan); Boonsathorn, Naphatsawan [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Department of Medical Sciences, Ministry of Public Health, Muang, Nonthaburi (Thailand); JST/JICA, Science and Technology Research Partnership for Sustainable Development (SATREPS), Tokyo (Japan); Ibrahim, Madiha S. [Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Damanhour University, Damanhour (Egypt); and others

    2014-07-18

    Highlights: • Influenza infection can elicit heterosubtypic antibodies to group 1 influenza virus. • Three human monoclonal antibodies were generated from an H1N1-infected patient. • The antibodies predominantly recognized α-helical stem of viral hemagglutinin (HA). • The antibodies inhibited HA structural activation during the fusion process. • The antibodies are potential candidates for future antibody therapy to influenza. - Abstract: Influenza viruses are a continuous threat to human public health because of their ability to evolve rapidly through genetic drift and reassortment. Three human monoclonal antibodies (HuMAbs) were generated in this study, 1H11, 2H5 and 5G2, and they cross-neutralize a diverse range of group 1 influenza A viruses, including seasonal H1N1, 2009 pandemic H1N1 (H1N1pdm) and avian H5N1 and H9N2. The three HuMAbs were prepared by fusing peripheral blood lymphocytes from an H1N1pdm-infected patient with a newly developed fusion partner cell line, SPYMEG. All the HuMAbs had little hemagglutination inhibition activity but had strong membrane-fusion inhibition activity against influenza viruses. A protease digestion assay showed the HuMAbs targeted commonly a short α-helix region in the stalk of the hemagglutinin. Furthermore, Ile45Phe and Glu47Gly double substitutions in the α-helix region made the HA unrecognizable by the HuMAbs. These two amino acid residues are highly conserved in the HAs of H1N1, H5N1 and H9N2 viruses. The HuMAbs reported here may be potential candidates for the development of therapeutic antibodies against group 1 influenza viruses.

  19. The Antiviral Mechanism of an Influenza A Virus Nucleoprotein-Specific Single-Domain Antibody Fragment

    Energy Technology Data Exchange (ETDEWEB)

    Hanke, Leo; Knockenhauer, Kevin E.; Brewer, R. Camille; van Diest, Eline; Schmidt, Florian I.; Schwartz, Thomas U.; Ploegh, Hidde L. (Whitehead); (MIT)

    2016-12-13

    Alpaca-derived single-domain antibody fragments (VHHs) that target the influenza A virus nucleoprotein (NP) can protect cells from infection when expressed in the cytosol. We found that one such VHH, αNP-VHH1, exhibits antiviral activity similar to that of Mx proteins by blocking nuclear import of incoming viral ribonucleoproteins (vRNPs) and viral transcription and replication in the nucleus. We determined a 3.2-Å crystal structure of αNP-VHH1 in complex with influenza A virus NP. The VHH binds to a nonconserved region on the body domain of NP, which has been associated with binding to host factors and serves as a determinant of host range. Several of the NP/VHH interface residues determine sensitivity of NP to antiviral Mx GTPases. The structure of the NP/αNP-VHH1 complex affords a plausible explanation for the inhibitory properties of the VHH and suggests a rationale for the antiviral properties of Mx proteins. Such knowledge can be leveraged for much-needed novel antiviral strategies.

    IMPORTANCEInfluenza virus strains can rapidly escape from protection afforded by seasonal vaccines or acquire resistance to available drugs. Additional ways to interfere with the virus life cycle are therefore urgently needed. The influenza virus nucleoprotein is one promising target for antiviral interventions. We have previously isolated alpaca-derived single-domain antibody fragments (VHHs) that protect cells from influenza virus infection if expressed intracellularly. We show here that one such VHH exhibits antiviral activities similar to those of proteins of the cellular antiviral defense (Mx proteins). We determined the three-dimensional structure of this VHH in complex with the influenza virus nucleoprotein and identified the interaction site, which overlaps regions that determine sensitivity of the virus to Mx proteins. Our data define a new vulnerability of influenza virus, help us to better understand the cellular antiviral mechanisms, and

  20. Characterization of antibody response in neuroinvasive infection caused by Toscana virus.

    Science.gov (United States)

    Pierro, A; Ficarelli, S; Ayhan, N; Morini, S; Raumer, L; Bartoletti, M; Mastroianni, A; Prati, F; Schivazappa, S; Cenni, P; Vocale, C; Rossini, G; Gaibani, P; Sambri, V; Landini, M P; Lewis, R E; Charrel, R N; Varani, S

    2017-11-01

    Among sandfly-borne pathogens, Toscana virus (TOSV) is a prominent cause of summer meningitis in Mediterranean Europe. Here, we assessed the kinetics of anti-TOSV antibodies over time in 41 patients diagnosed with TOSV meningitis or meningoencephalitis in northeastern Italy. Acute and follow-up serum samples were collected up to 20 months after diagnosis of TOSV infection and tested for the presence of specific antibody using immunoenzymatic and indirect immunofluorescence assays. In addition, maturation of anti-TOSV IgG over time was evaluated as well as production of neutralizing antibodies. Specific IgM and IgG response was present at diagnosis in 100% of patients; TOSV-specific IgM and IgG were detected in patients' sera up to 6 and 20 months after diagnosis, respectively. The avidity index (AI) increased over the first month after infection in 100% of patients and most cases exceeded 60% by Day 30 post infection. The AI subsequently plateaued then declined at 20 months after diagnosis. Finally, neutralization assay to TOSV was performed in 217 sera collected from 41 patients; 69.6% of tested samples resulted in reactive and moderate levels of neutralizing antibodies observed during all phases of infection despite high titres of total anti-TOSV IgG. Specific antibody response develops rapidly and is long-lasting for neuroinvasive TOSV infection. Serodiagnosis of neuroinvasive TOSV requires simultaneous detection of specific IgM and IgG. Moderate levels of neutralizing antibodies were maintained over the study period, while the protective role of antibodies lacking neutralizing activity is unclear and requires further evaluation. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  1. [Evaluation of serum levels of tick-borne encephalitis (TBE) virus antibodies after administration of FSME inject vaccine].

    Science.gov (United States)

    Pancewicz, Sławomir A; Hermanowska-Szpakowicz, Teresa

    2002-01-01

    The purpose of this work was to evaluate the changes of anti-TBE virus antibodies serum concentration 3 months after administration of FSME Inject vaccine. The detection of IgG antibodies against TBE virus was performed in sera of 106 forest workers aged mean = 41.5. These sera were examined twice before and after vaccine administration using FSME Kombi-Kit. According to producer's information the "safe" concentration, which protects from TBE virus infection, is over 11VE. In examination 126 (24.5%) sera showed concentration of examined antibodies lower than 11 VE but in 80 (75.5%) sera antibodies concentration was from 12 to 47 VE (mean = 24.15 VE). In the examination 2 significant increase of antibodies concentration was stated. In all sera the concentration ranged from 9 to 62 VE (mean = 39.83 VE). The administration of TBE vaccine booster causes quick increase of antibodies against TBE virus to the level which is considered to be protective against TBE virus infection.

  2. Generation of Recombinant Schmallenberg Virus Nucleocapsid Protein in Yeast and Development of Virus-Specific Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Justas Lazutka

    2014-01-01

    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.

  3. 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

    2014-01-01

    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.

  4. Immunological Detection of Rabies Virus in Brain Tissues of Infected Dogs by Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Nyoman Mantik Astawa

    2010-12-01

    Full Text Available In order to establish an immunological detection of rabies virus in tissues of infected dogs, monoclonalantibodies (mAbs against rabies virus (RV were produced. The mAbs were produced by fusion of mielomacells with the lymphocytes of mice immunized with RV. The mAbs produced were then characterized andused for the detection of rabies virus in brain tissues of infected dogs. Six mAbs designated CC6, EG4,DG10, BB12, CA9 dan EB5 were used in this study. In Western blotting test, some mAbs reacted with 66KDa which is the glycoprotein of the virus. In immunoperoxidase, 2 mAbs (CC6 and DG10 detected RVin the brain of infected dogs. By direct immunoflourescence, flourescence isotyocyanate (FITC labelledDG10 mAbs detected RV in fresh and formaldehyde fixed brain tissues. RV was detected in 12 infecteddogs but not in normal uninfected dogs. In this study it was confirmed that rabies virus can be detected inthe brain tissues of infected dogs by monoclonal antibodies.

  5. Neutralization of White Spot Syndrome Virus by Monoclonal Antibodies against Viral Envelope Proteins

    Directory of Open Access Journals (Sweden)

    Hsiu-Hui Shih

    2004-09-01

    Full Text Available Two monoclonal antibodies (MAbs recognizing envelope proteins of the white spot syndrome virus (WSSV, 6E1 against VP28 and 3E8 against VP19, were applied to demonstrate their neutralizing ability to this virus by using both in vitro and in vivo assays. Mixtures of MAb 6E1 with virus filtrate were inoculated into the primary explant monolayer culture derived from the lymphoid Oka organs of Penaeus monodon. Mab was likely to neutralize the infectivity of virus to monolayer since cytopathic effects were apparently blocked in experiment group. WSSV was titrated using Blue-Cell ELISA and the neutralizing index was calculated to be 6.90 for 6EI and 5.83 for 3E8. Neutralized virus fluids injected intramuscularly into post larvae of P. monodon. The shrimp in the positive control, which were injected with WSSV only showed an increasing mortality and a 100% mortality was reached at day 34, whereas no shrimp died in the negative control. The mortality for 6E1 was 6.7% and for 3E8 was 13.3%. These results suggest that Mabs recognizing the WSSV envelope proteins could neutralize viral infectivity to both cultured cells and shrimp.

  6. Production of Polyclonal Antibody against Grapevine fanleaf virus Movement Protein Expressed in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Davoud Koolivand

    2016-10-01

    Full Text Available The genomic region of Grapevine fanleaf virus (GFLV encoding the movement protein (MP was cloned into pET21a and transformed into Escherichia coli strain BL21 (DE3 to express the protein. Induction was made with a wide range of isopropyl-β-D-thiogalactopyranoside (IPTG concentrations (1, 1.5, and 2 mM each for duration of 4, 6, or 16 h. However, the highest expression level was achieved with 1 mM IPTG for 4 h. Identity of the expressed protein was confirmed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE followed by Western blotting. The expressed 41 kDa protein was purified under denaturing condition by affinity chromatography, reconfirmed by Western blotting and plate-trapped antigen enzyme-linked immunosorbent assay (PTA-ELISA before being used as a recombinant antigen to raise polyclonal antibodies in rabbits. Purified anti-GFLV MP immunoglobulines (IgGs and conjugated IgGs detected the expressed MP and GFLV virions in infected grapevines when used in PTA-ELISA, double antibody sandwich-ELISA, and Western blotting. This is the first report on the production of anti-GFLV MP polyclonal antibodies and application for the virus detection.

  7. High seroprevalence of antibodies to avian influenza viruses among wild waterfowl in Alaska: implications for surveillance

    Science.gov (United States)

    Wilson, Heather M.; Hall, Jeffery S.; Flint, Paul L.; Franson, J. Christian; Ely, Craig R.; Schmutz, Joel A.; Samuel, Michael D.

    2013-01-01

    We examined seroprevalence (presence of detectable antibodies in serum) for avian influenza viruses (AIV) among 4,485 birds, from 11 species of wild waterfowl in Alaska (1998–2010), sampled during breeding/molting periods. Seroprevalence varied among species (highest in eiders (Somateria and Polysticta species), and emperor geese (Chen canagica)), ages (adults higher than juveniles), across geographic locations (highest in the Arctic and Alaska Peninsula) and among years in tundra swans (Cygnus columbianus). All seroprevalence rates in excess of 60% were found in marine-dependent species. Seroprevalence was much higher than AIV infection based on rRT-PCR or virus isolation alone. Because pre-existing AIV antibodies can infer some protection against highly pathogenic AIV (HPAI H5N1), our results imply that some wild waterfowl in Alaska could be protected from lethal HPAIV infections. Seroprevalence should be considered in deciphering patterns of exposure, differential infection, and rates of AIV transmission. Our results suggest surveillance programs include species and populations with high AIV seroprevalences, in addition to those with high infection rates. Serologic testing, including examination of serotype-specific antibodies throughout the annual cycle, would help to better assess spatial and temporal patterns of AIV transmission and overall disease dynamics.

  8. Fusion Peptide Improves Stability and Bioactivity of Single Chain Antibody against Rabies Virus.

    Science.gov (United States)

    Xi, Hualong; Zhang, Kaixin; Yin, Yanchun; Gu, Tiejun; Sun, Qing; Shi, Linqing; Zhang, Renxia; Jiang, Chunlai; Kong, Wei; Wu, Yongge

    2017-04-28

    The combination of rabies immunoglobulin (RIG) with a vaccine is currently effective against rabies infections, but improvements are needed. Genetic engineering antibody technology is an attractive approach for developing novel antibodies to replace RIG. In our previous study, a single-chain variable fragment, scFv57R, against rabies virus glycoprotein was constructed. However, its inherent weak stability and short half-life compared with the parent RIG may limit its diagnostic and therapeutic application. Therefore, an acidic tail of synuclein (ATS) derived from the C-terminal acidic tail of human alpha-synuclein protein was fused to the C-terminus of scFv57R in order to help it resist adverse stress and improve the stability and halflife. The tail showed no apparent effect on the preparation procedure and affinity of the protein, nor did it change the neutralizing potency in vitro. In the ELISA test of molecular stability, the ATS fusion form of the protein, scFv57R-ATS, showed an increase in thermal stability and longer half-life in serum than scFv57R. The protection against fatal rabies virus challenge improved after fusing the tail to the scFv, which may be attributed to the improved stability. Thus, the ATS fusion approach presented here is easily implemented and can be used as a new strategy to improve the stability and half-life of engineered antibody proteins for practical applications.

  9. Structures of protective antibodies reveal sites of vulnerability on Ebola virus.

    Science.gov (United States)

    Murin, Charles D; Fusco, Marnie L; Bornholdt, Zachary A; Qiu, Xiangguo; Olinger, Gene G; Zeitlin, Larry; Kobinger, Gary P; Ward, Andrew B; Saphire, Erica Ollmann

    2014-12-02

    Ebola virus (EBOV) and related filoviruses cause severe hemorrhagic fever, with up to 90% lethality, and no treatments are approved for human use. Multiple recent outbreaks of EBOV and the likelihood of future human exposure highlight the need for pre- and postexposure treatments. Monoclonal antibody (mAb) cocktails are particularly attractive candidates due to their proven postexposure efficacy in nonhuman primate models of EBOV infection. Two candidate cocktails, MB-003 and ZMAb, have been extensively evaluated in both in vitro and in vivo studies. Recently, these two therapeutics have been combined into a new cocktail named ZMapp, which showed increased efficacy and has been given compassionately to some human patients. Epitope information and mechanism of action are currently unknown for most of the component mAbs. Here we provide single-particle EM reconstructions of every mAb in the ZMapp cocktail, as well as additional antibodies from MB-003 and ZMAb. Our results illuminate key and recurring sites of vulnerability on the EBOV glycoprotein and provide a structural rationale for the efficacy of ZMapp. Interestingly, two of its components recognize overlapping epitopes and compete with each other for binding. Going forward, this work now provides a basis for strategic selection of next-generation antibody cocktails against Ebola and related viruses and a model for predicting the impact of ZMapp on potential escape mutations in ongoing or future Ebola outbreaks.

  10. Antibody titers for canine parvovirus type-2, canine distemper virus, and canine adenovirus type-1 in adult household dogs.

    Science.gov (United States)

    Taguchi, Masayuki; Namikawa, Kazuhiko; Maruo, Takuya; Orito, Kensuke; Lynch, Jonathan; Sahara, Hiroeki

    2011-09-01

    Serum antibody titers for canine parvovirus type-2 (CPV-2), canine distemper virus (CDV) and canine adenovirus type-1 (CAV-1) were investigated in 1031 healthy adult household dogs (2 to 18 years old) given an annual inoculation in the previous 11 to 13 months. The number of dogs retaining significant titers of antibodies against CPV-2, CDV, and CAV-1 were 888 (86%), 744 (72%), and 732 (71%), respectively. There were no differences between males and females in antibody titers against the 3 viruses. Antibody titer for CPV-2 was significantly higher in younger dogs than in older dogs, CDV antibody was significantly higher in older dogs than in younger dogs, and CAV titer was not associated with age.

  11. Challenges for bovine viral diarrhoea virus antibody detection in bulk milk by antibody enzyme-linked immunosorbent assays due to changes in milk production levels

    DEFF Research Database (Denmark)

    Foddai, Alessandro; Enøe, Claes; Stockmarr, Anders

    2015-01-01

    Background: Bovine viral diarrhoea (BVD) is considered eradicated from Denmark. Currently, very few (if any) Danish cattle herds could be infected with BVD virus (BVDV). The Danish antibody blocking enzyme-linked immunosorbent assay (ELISA) has been successfully used during the Danish BVD eradica...

  12. Isolation of recombinant phage antibodies targeting the hemagglutinin cleavage site of highly pathogenic avian influenza virus.

    Directory of Open Access Journals (Sweden)

    Jinhua Dong

    Full Text Available Highly pathogenic avian influenza (HPAI H5N1 viruses, which have emerged in poultry and other wildlife worldwide, contain a characteristic multi-basic cleavage site (CS in the hemagglutinin protein (HA. Because this arginine-rich CS is unique among influenza virus subtypes, antibodies against this site have the potential to specifically diagnose pathogenic H5N1. By immunizing mice with the CS peptide and screening a phage display library, we isolated four antibody Fab fragment clones that specifically bind the antigen peptide and several HPAI H5N1 HA proteins in different clades. The soluble Fab fragments expressed in Escherichia coli bound the CS peptide and the H5N1 HA protein with nanomolar affinity. In an immunofluorescence assay, these Fab fragments stained cells infected with HPAI H5N1 but not those infected with a less virulent strain. Lastly, all the Fab clones could detect the CS peptide and H5N1 HA protein by open sandwich ELISA. Thus, these recombinant Fab fragments will be useful novel reagents for the rapid and specific detection of HPAI H5N1 virus.

  13. Detection of Schmallenberg virus antibody in equine population of Northern and Northeast of Iran

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    M. Rasekh

    2018-01-01

    Full Text Available Aim: Schmallenberg virus (SBV is a newly emerging virus in Simbu group that 1st time is reported in 2011 in Germany and now spread to Europe. The clinical signs of infection to this virus are fever, loss of appetite, reduced milk yield and in some cases, diarrhea and in pregnant animals congenital malformations in calves, lambs, and kid goats. Materials and Methods: In this study for a serologic survey of SBV, blood samples from 200 horse in different rural areas of the northern and northeast of Iran with the high equine population collected and were analyzed using an indirect ELISA test. Results: Based on our results 5% (n=10 of total 200 samples were positive for SBV antibody and 2% (n=4 was doubtful and 93% (n=186 was negative. There were no significant differences between age and sex and breed properties (p>0.05. Conclusion: This study demonstrated the presence of antibodies against the SBV on horse populations in Iran. The high population and activity of Culicoides biting midges and their proper living conditions, especially the areas of temperate and humid environmental conditions, are the possible causes of arboviruses related diseases seen in this country.

  14. Detection of Schmallenberg virus antibody in equine population of Northern and Northeast of Iran.

    Science.gov (United States)

    Rasekh, M; Sarani, A; Hashemi, S H

    2018-01-01

    Schmallenberg virus (SBV) is a newly emerging virus in Simbu group that 1 st time is reported in 2011 in Germany and now spread to Europe. The clinical signs of infection to this virus are fever, loss of appetite, reduced milk yield and in some cases, diarrhea and in pregnant animals congenital malformations in calves, lambs, and kid goats. In this study for a serologic survey of SBV, blood samples from 200 horse in different rural areas of the northern and northeast of Iran with the high equine population collected and were analyzed using an indirect ELISA test. Based on our results 5% (n=10) of total 200 samples were positive for SBV antibody and 2% (n=4) was doubtful and 93% (n=186) was negative. There were no significant differences between age and sex and breed properties (p>0.05). This study demonstrated the presence of antibodies against the SBV on horse populations in Iran. The high population and activity of Culicoides biting midges and their proper living conditions, especially the areas of temperate and humid environmental conditions, are the possible causes of arboviruses related diseases seen in this country.

  15. Neutralising antibody response in domestic cats immunised with a commercial feline immunodeficiency virus (FIV) vaccine.

    Science.gov (United States)

    Bęczkowski, Paweł M; Harris, Matthew; Techakriengkrai, Navapon; Beatty, Julia A; Willett, Brian J; Hosie, Margaret J

    2015-02-18

    Across human and veterinary medicine, vaccines against only two retroviral infections have been brought to market successfully, the vaccines against feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV). FeLV vaccines have been a global success story, reducing virus prevalence in countries where uptake is high. In contrast, the more recent FIV vaccine was introduced in 2002 and the degree of protection afforded in the field remains to be established. However, given the similarities between FIV and HIV, field studies of FIV vaccine efficacy are likely to advise and inform the development of future approaches to HIV vaccination. Here we assessed the neutralising antibody response induced by FIV vaccination against a panel of FIV isolates, by testing blood samples collected from client-owned vaccinated Australian cats. We examined the molecular and phenotypic properties of 24 envs isolated from one vaccinated cat that we speculated might have become infected following natural exposure to FIV. Cats vaccinated against FIV did not display broadly neutralising antibodies, suggesting that protection may not extend to some virulent recombinant strains of FIV circulating in Australia. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. CROSSREACTIVE ANTIBODIES AND MEMORY T CELLS TO HUMAN AND ZOONOTIC INFLUENZA A VIRUSES IN VOLUNTEERS

    Directory of Open Access Journals (Sweden)

    I. V. Losev

    2015-01-01

    Full Text Available There exists a real hazard of transferring zoonotic influenza A viruses, either swine, or avian, into human population. In such case, severity of such pandemics depends on the pathogen-specific immunity in the population. Virtual absence of such immunity in humans was declared in the literature. In this work, we assessed systemic, local, and T-cell immunity to potentially pandemic H3N2sw, H5N1, H5N2, H7N3, H7N9 and H2N2 influenza A viruses in a group of healthy adults of different age. Our results indicate that these subjects develop the following immune reactions: (i local (i.e., nasal IgA and cellular (CD4+ and CD8v memory T cells heterosubtypic immunity, in absence of detectable virus-specific serum antibodies to avian influenza A viruses; (ii Local immune responses (as nasal IgA to human A (H2N2 virus which circulated in 1957-1968 were detected both in subjects who could be primed at that time, but also in subjects born after 1968; (iii full-scale systemic and local immunity to potentially pandemic А (H3N2sw swine virus was found in the group. Conclusion. In order of proper epidemiological forecasts and planning appropriate preventive measures for potentially pandemic Influenza A viruses, a regular monitoring of collective immunity should be performed using different adaptive markers. In this respect, any conclusion based on molecular analysis only could lead to considerable mistakes, and should be accomplished by the mentioned immunological studies.

  17. Pichia pastoris-Expressed Bivalent Virus-Like Particulate Vaccine Induces Domain III-Focused Bivalent Neutralizing Antibodies without Antibody-Dependent Enhancement in Vivo

    Directory of Open Access Journals (Sweden)

    Rahul Shukla

    2018-01-01

    Full Text Available Dengue, a significant public health problem in several countries around the world, is caused by four different serotypes of mosquito-borne dengue viruses (DENV-1, -2, -3, and -4. Antibodies to any one DENV serotype which can protect against homotypic re-infection, do not offer heterotypic cross-protection. In fact, cross-reactive antibodies may augment heterotypic DENV infection through antibody-dependent enhancement (ADE. A recently launched live attenuated vaccine (LAV for dengue, which consists of a mixture of four chimeric yellow-fever/dengue vaccine viruses, may be linked to the induction of disease-enhancing antibodies. This is likely related to viral interference among the replicating viral strains, resulting in an unbalanced immune response, as well as to the fact that the LAV encodes prM, a DENV protein documented to elicit ADE-mediating antibodies. This makes it imperative to explore the feasibility of alternate ADE risk-free vaccine candidates. Our quest for a non-replicating vaccine centered on the DENV envelope (E protein which mediates virus entry into the host cell and serves as an important target of the immune response. Serotype-specific neutralizing epitopes and the host receptor recognition function map to E domain III (EDIII. Recently, we found that Pichia pastoris-expressed DENV E protein, of all four serotypes, self-assembled into virus-like particles (VLPs in the absence of prM. Significantly, these VLPs displayed EDIII and elicited EDIII-focused DENV-neutralizing antibodies in mice. We now report the creation and characterization of a novel non-replicating recombinant particulate vaccine candidate, produced by co-expressing the E proteins of DENV-1 and DENV-2 in P. pastoris. The two E proteins co-assembled into bivalent mosaic VLPs (mVLPs designated as mE1E2bv VLPs. The mVLP, which preserved the serotype-specific antigenic integrity of its two component proteins, elicited predominantly EDIII-focused homotypic virus

  18. Rapid transient production in plants by replicating and non-replicating vectors yields high quality functional anti-HIV antibody.

    Directory of Open Access Journals (Sweden)

    Frank Sainsbury

    2010-11-01

    Full Text Available The capacity of plants and plant cells to produce large amounts of recombinant protein has been well established. Due to advantages in terms of speed and yield, attention has recently turned towards the use of transient expression systems, including viral vectors, to produce proteins of pharmaceutical interest in plants. However, the effects of such high level expression from viral vectors and concomitant effects on host cells may affect the quality of the recombinant product.To assess the quality of antibodies transiently expressed to high levels in plants, we have expressed and characterised the human anti-HIV monoclonal antibody, 2G12, using both replicating and non-replicating systems based on deleted versions of Cowpea mosaic virus (CPMV RNA-2. The highest yield (approximately 100 mg/kg wet weight leaf tissue of affinity purified 2G12 was obtained when the non-replicating CPMV-HT system was used and the antibody was retained in the endoplasmic reticulum (ER. Glycan analysis by mass-spectrometry showed that the glycosylation pattern was determined exclusively by whether the antibody was retained in the ER and did not depend on whether a replicating or non-replicating system was used. Characterisation of the binding and neutralisation properties of all the purified 2G12 variants from plants showed that these were generally similar to those of the Chinese hamster ovary (CHO cell-produced 2G12.Overall, the results demonstrate that replicating and non-replicating CPMV-based vectors are able to direct the production of a recombinant IgG similar in activity to the CHO-produced control. Thus, a complex recombinant protein was produced with no apparent effect on its biochemical properties using either high-level expression or viral replication. The speed with which a recombinant pharmaceutical with excellent biochemical characteristics can be produced transiently in plants makes CPMV-based expression vectors an attractive option for

  19. Neutralization of feline immunodeficiency virus by polyclonal cat antibody: Simultaneous involvement of hypervariable regions 4 and 5 of the surface glycoprotein.

    NARCIS (Netherlands)

    C.H.J. Siebelink (Kees); W. Huisman (Willem); J.A. Karlas (Jos); G.F. Rimmelzwaan (Guus); M.L. Bosch (Marnix); A.D.M.E. Osterhaus (Albert)

    1995-01-01

    textabstractSites involved in antibody-mediated neutralization of feline immunodeficiency virus were mapped by reciprocal exchange of envelope fragments or amino acids between molecular clones of feline immunodeficiency virus with different susceptibilities to neutralization by a polyclonal cat

  20. A neutralizing human monoclonal antibody protects against lethal disease in a new ferret model of acute nipah virus infection.

    Directory of Open Access Journals (Sweden)

    Katharine N Bossart

    2009-10-01

    Full Text Available Nipah virus is a broadly tropic and highly pathogenic zoonotic paramyxovirus in the genus Henipavirus whose natural reservoirs are several species of Pteropus fruit bats. Nipah virus has repeatedly caused outbreaks over the past decade associated with a severe and often fatal disease in humans and animals. Here, a new ferret model of Nipah virus pathogenesis is described where both respiratory and neurological disease are present in infected animals. Severe disease occurs with viral doses as low as 500 TCID(50 within 6 to 10 days following infection. The underlying pathology seen in the ferret closely resembles that seen in Nipah virus infected humans, characterized as a widespread multisystemic vasculitis, with virus replicating in highly vascular tissues including lung, spleen and brain, with recoverable virus from a variety of tissues. Using this ferret model a cross-reactive neutralizing human monoclonal antibody, m102.4, targeting the henipavirus G glycoprotein was evaluated in vivo as a potential therapeutic agent. All ferrets that received m102.4 ten hours following a high dose oral-nasal Nipah virus challenge were protected from disease while all controls died. This study is the first successful post-exposure passive antibody therapy for Nipah virus using a human monoclonal antibody.

  1. Complexity of Human Antibody Response to Dengue Virus: Implication for Vaccine Development.

    Science.gov (United States)

    Tsai, Wen-Yang; Lin, Hong-En; Wang, Wei-Kung

    2017-01-01

    The four serotypes of dengue virus (DENV) are the leading cause of arboviral diseases in humans. Decades of efforts have made remarkable progress in dengue vaccine development. Despite the first dengue vaccine (dengvaxia from Sanofi Pasteur), a live-attenuated tetravalent chimeric yellow fever-dengue vaccine, has been licensed by several countries since 2016, its overall moderate efficacy (56.5-60.8%) in the presence of neutralizing antibodies during the Phase 2b and 3 trials, lower efficacy among dengue naïve compared with dengue experienced individuals, and increased risk of hospitalization among young children during the follow-up highlight the need for a better understanding of humoral responses after natural DENV infection. Recent studies of more than 300 human monoclonal antibodies (mAbs) against DENV have led to the discovery of several novel epitopes on the envelope protein recognized by potent neutralizing mAbs. This information together with in-depth studies on polyclonal sera and B-cells following natural DENV infection has tremendous implications for better immunogen design for a safe and effective dengue vaccine. This review outlines the progress in our understanding of mouse mAbs, human mAbs, and polyclonal sera against DENV envelope and precursor membrane proteins, two surface proteins involved in vaccine development, following natural infection; analyses of these discoveries have provided valuable insight into new strategies involving molecular technology to induce more potent neutralizing antibodies and less enhancing antibodies for next-generation dengue vaccine development.

  2. Antibody Level Upon Newcastle Disease Virus In Chicken After Exposure To GAMMA Radiation

    International Nuclear Information System (INIS)

    Pejakovic-Hlede, J.; Dotur, J.; Pasic, S.; Gottstein, Z.; Majer, M.; Vilic, M.

    2015-01-01

    The aim of this study was to investigate the effect of gamma radiation upon Newcastle disease virus antibody level after acute exposure with dose of 0.05 Gy and 0.8 Gy gamma radiation. The experiment was made on light chicken breeds irradiated with dose of 0.05 Gy and 0.8 Gy gamma radiation with dose rate of 0.0117 Gy/s on the first and on the third day after hatching. Chicken were vaccinated by nebulization on the first day after hatching. Antibody level upon Newcastle disease in blood serum of chicken was quantified by hemagglutination inhibition assay on 1th, 7th, 14th and 28th day after vaccination. Results demonstrate that antibody titre against Newcastle disease in blood serum of chicken irradiated with dose of 0.05 Gy and 0.8 Gy gamma radiation on the first and on the third day after hatching was not statistically significant. Therefore, these results suggest that irradiation of light chicken breeds on the first and third day after vaccination with dose of 0.05 Gy and 0.8 Gy does not change antibody titre upon Newcastle disease. (author).

  3. Low Titers of Canine Distemper Virus Antibody in Wild Fishers (Martes pennanti) in the Eastern USA.

    Science.gov (United States)

    Peper, Steven T; Peper, Randall L; Mitcheltree, Denise H; Kollias, George V; Brooks, Robert P; Stevens, Sadie S; Serfass, Thomas L

    2016-01-01

    Canine distemper virus (CDV) infects species in the order Carnivora. Members of the family Mustelidae are among the species most susceptible to CDV and have a high mortality rate after infection. Assessing an animal's pathogen or disease load prior to any reintroduction project is important to help protect the animal being reintroduced, as well as the wildlife and livestock in the area of relocation. We screened 58 fishers for CDV antibody prior to their release into Pennsylvania, US, as part of a reintroduction program. Five of the 58 (9%) fishers had a weak-positive reaction for CDV antibody at a dilution of 1:16. None of the fishers exhibited any clinical sign of canine distemper while being held prior to release.

  4. High prevalence of antibodies against hepatitis A virus among captive nonhuman primates.

    Science.gov (United States)

    Sa-nguanmoo, Pattaratida; Thawornsuk, Nutchanart; Rianthavorn, Pornpimol; Sommanustweechai, Angkana; Ratanakorn, Parntep; Poovorawan, Yong

    2010-04-01

    Hepatitis A virus (HAV) can infect not only humans but also several other nonhuman primates. This study has been conducted to evaluate the comprehensive anti-HAV seroprevalence in captive nonhuman primate populations in Thailand. The prevalence of antibodies against HAV in 96 captive nonhuman primates of 11 species was evaluated by competitive enzyme immunoassay (EIA). HAV antibodies were found in 64.7% (11/17) of macaques, 85.7% (6/7) of langurs, 28.4% (10/35) of gibbons, and 94.6% (35/37) of orangutans. However, anti-HAV IgM was not found in any sera. These results indicate that the majority of captive nonhuman primates in Thailand were exposed to HAV. It is possible that some of the animals were infected prior to capture.

  5. Serum albumin 'camouflage' of plant virus based nanoparticles prevents their antibody recognition and enhances pharmacokinetics.

    Science.gov (United States)

    Pitek, Andrzej S; Jameson, Slater A; Veliz, Frank A; Shukla, Sourabh; Steinmetz, Nicole F

    2016-05-01

    Plant virus-based nanoparticles (VNPs) are a novel class of nanocarriers with unique potential for biomedical applications. VNPs have many advantageous properties such as ease of manufacture and high degree of quality control. Their biocompatibility and biodegradability make them an attractive alternative to synthetic nanoparticles (NPs). Nevertheless, as with synthetic NPs, to be successful in drug delivery or imaging, the carriers need to overcome several biological barriers including innate immune recognition. Plasma opsonization can tag (V)NPs for clearance by the mononuclear phagocyte system (MPS), resulting in shortened circulation half lives and non-specific sequestration in non-targeted organs. PEG coatings have been traditionally used to 'shield' nanocarriers from immune surveillance. However, due to broad use of PEG in cosmetics and other industries, the prevalence of anti-PEG antibodies has been reported, which may limit the utility of PEGylation in nanomedicine. Alternative strategies are needed to tailor the in vivo properties of (plant virus-based) nanocarriers. We demonstrate the use of serum albumin (SA) as a viable alternative. SA conjugation to tobacco mosaic virus (TMV)-based nanocarriers results in a 'camouflage' effect more effective than PEG coatings. SA-'camouflaged' TMV particles exhibit decreased antibody recognition, as well as enhanced pharmacokinetics in a Balb/C mouse model. Therefore, SA-coatings may provide an alternative and improved coating technique to yield (plant virus-based) NPs with improved in vivo properties enhancing drug delivery and molecular imaging. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Neutralizing and non-neutralizing monoclonal antibodies against dengue virus E protein derived from a naturally infected patient

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    Isern Sharon

    2010-02-01

    Full Text Available Abstract Background Antibodies produced in response to infection with any of the four serotypes of dengue virus generally provide homotypic immunity. However, prior infection or circulating maternal antibodies can also mediate a non-protective antibody response that can enhance the course of disease in a subsequent heterotypic infection. Naturally occurring human monoclonal antibodies can help us understand the protective and pathogenic roles of the humoral immune system in dengue virus infection. Results Epstein-Barr Virus (EBV transformation of B cells isolated from the peripheral blood of a human subject with previous dengue infection was performed. B cell cultures were screened by ELISA for antibodies to dengue (DENV envelope (E protein. ELISA positive cultures were cloned by limiting dilution. Three IgG1 human monoclonal antibodies (HMAbs were purified and their binding specificity to E protein was verified by ELISA and biolayer interferometry. Neutralization and enhancement assays were conducted in epithelial and macrophage-like cell lines, respectively. All three HMAbs bound to E from at least two of the four DENV serotypes, one of the HMAbs was neutralizing, and all were able to enhance DENV infection. Conclusions HMAbs against DENV can be successfully generated by EBV transformation of B cells from patients at least two years after naturally acquired DENV infections. These antibodies show different patterns of cross-reactivity, neutralizing, and enhancement activity.

  7. Development of a virus neutralisation test to detect antibodies against Schmallenberg virus and serological results in suspect and infected herds

    Directory of Open Access Journals (Sweden)

    Loeffen Willie

    2012-08-01

    Full Text Available Abstract Background At the end of 2011, a new orthobunyavirus, tentatively named Schmallenberg virus (SBV, was discovered in Germany. This virus has since been associated with clinical signs of decreased milk production, watery diarrhoea and fever in dairy cows, and subsequently also with congenital malformations in calves, lambs and goat kids. In affected countries, initial surveillance for the infection was based on examination of malformed progeny. These suspicions were followed up by real-time reverse transcription polymerase chain reaction (RT-PCR on brain tissue. For epidemiological purposes, a serological assay was, however, needed. Results A virus neutralisation test (VNT was developed and optimized, and subsequently evaluated. This VNT has a specificity of >99% and the sensitivity is likely also very close to 100%. The assay is highly repeatable and reproducible. The final assay was used to test for antibodies in cows, ewes and does from herds known to be infected or suspected to be so. Targets for sampling in these herds were the mothers of malformed offspring. In herds with an RT-PCR confirmed SBV infection, more than 94% (190 out of 201 of the ewes and 99% (145 out of 146 of the cows were seropositive. In herds with suspicion of SBV infection based on birth of malformed offspring only (no or negative RT-PCR, more than 90% (231 out of 255 of the ewes and 95% (795 out of 834 of the cows were seropositive. In goats, on the other hand, only a low number of seropositives was found: overall 36.4%, being 16 out of 44 goats tested. Conclusions Given the characteristics of this VNT, it can be used at a relative high throughput for testing of animals for export, surveillance, screening and research purposes, but can also be used as a confirmation test for commercially available enzyme-linked immunosorbent assays (ELISA’s and for (relative quantification of antibodies. Suspicions of SBV infections that were confirmed by RT-PCR were almost

  8. Robust production of virus-like particles and monoclonal antibodies with geminiviral replicon vectors in lettuce

    Science.gov (United States)

    Lai, Huafang; He, Junyun; Engle, Michael; Diamond, Michael S.; Chen, Qiang

    2011-01-01

    Summary Pharmaceutical protein production in plants has been greatly promoted by the development of viral-based vectors and transient expression systems. Tobacco and related Nicotiana species are currently the most common host plants for generation of plant-made pharmaceutical proteins (PMPs). Downstream processing of target PMPs from these plants, however, is hindered by potential technical and regulatory difficulties due to the presence of high levels of phenolics and toxic alkaloids. Here, we explored the use of lettuce, which grows quickly yet produces low levels of secondary metabolites, and viral vector-based transient expression systems to develop a robust PMP production platform. Our results showed that a geminiviral replicon system based on the bean yellow dwarf virus permits high-level expression in lettuce of virus-like particles (VLP) derived from the Norwalk virus capsid protein and therapeutic monoclonal antibodies (mAbs) against Ebola and West Nile viruses. These vaccine and therapeutic candidates can be readily purified from lettuce leaves with scalable processing methods while fully retaining functional activity. Furthermore, this study also demonstrated the feasibility of using commercially produced lettuce for high-level PMP production. This allows our production system to have access to unlimited quantities of inexpensive plant material for large-scale production. These results establish a new production platform for biological pharmaceutical agents that is effective, safe, low-cost, and amenable to large-scale manufacturing. PMID:21883868

  9. Fetal demise and failed antibody therapy during Zika virus infection of pregnant macaques.

    Science.gov (United States)

    Magnani, Diogo M; Rogers, Thomas F; Maness, Nicholas J; Grubaugh, Nathan D; Beutler, Nathan; Bailey, Varian K; Gonzalez-Nieto, Lucas; Gutman, Martin J; Pedreño-Lopez, Núria; Kwal, Jaclyn M; Ricciardi, Michael J; Myers, Tereance A; Julander, Justin G; Bohm, Rudolf P; Gilbert, Margaret H; Schiro, Faith; Aye, Pyone P; Blair, Robert V; Martins, Mauricio A; Falkenstein, Kathrine P; Kaur, Amitinder; Curry, Christine L; Kallas, Esper G; Desrosiers, Ronald C; Goldschmidt-Clermont, Pascal J; Whitehead, Stephen S; Andersen, Kristian G; Bonaldo, Myrna C; Lackner, Andrew A; Panganiban, Antonito T; Burton, Dennis R; Watkins, David I

    2018-04-24

    Zika virus (ZIKV) infection of pregnant women is associated with pathologic complications of fetal development. Here, we infect pregnant rhesus macaques (Macaca mulatta) with a minimally passaged ZIKV isolate from Rio de Janeiro, where a high rate of fetal development complications was observed. The infection of pregnant macaques with this virus results in maternal viremia, virus crossing into the amniotic fluid (AF), and in utero fetal deaths. We also treated three additional ZIKV-infected pregnant macaques with a cocktail of ZIKV-neutralizing human monoclonal antibodies (nmAbs) at peak viremia. While the nmAbs can be effective in clearing the virus from the maternal sera of treated monkeys, it is not sufficient to clear ZIKV from AF. Our report suggests that ZIKV from Brazil causes fetal demise in non-human primates (NHPs) without additional mutations or confounding co-factors. Treatment with a neutralizing anti-ZIKV nmAb cocktail is insufficient to fully stop vertical transmission.

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

    Directory of Open Access Journals (Sweden)

    Encheng Sun

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

  11. Late radiation effects of low doses from occupational exposure. Antibodies to cytomegalovirus, Epstein-Barr virus and human T cell lymphotropic virus type 1 in radiological technologists

    Energy Technology Data Exchange (ETDEWEB)

    Kumagai, Etsuko; Tanoue, Shozo (Kumamoto Univ. (Japan). Coll. of Medical Science); Sawada, Shozo

    1989-05-01

    To elucidate the effects of long-term exposure to low dose irradiation, serostatus of antibodies to cytomegalovirus (CMV), Epstein-Barr virus (EBV) and human T cell lymphotropic virus type 1 (HTLV-1) was determined in 99 radiological technologists and 96 healthy volunteers. Abnormal seropositivity rate for CMV was significantly higher in technologists working for 15 years or more than in those working for less than 15 years. For the same age group, however, there was no significant difference between technologists and controls. Seropositivity rates for EBV-viral capsid antigen (VSA)/IgG and early antigen (EA)/IgG were significantly higher in technologists working for 15 years or more than in the age-matched control group. In the group of technologists exposed to 0.3 Sv or more, seropositivity rates of these antibodies were significantly higher than in those exposed to less than 0.3 Sv. However, there was no correlation between exposure doses and both EBV-associated nuclear antigen antibody and HTLV-1 antibody. Few technologists seronegative for CMV antibody had seropositive antibodies of EBV-VCA/IgG and EA/IgG. For technologists seropositive for CMV antibody, 31% and 54% were seropositive for EBV-VCA/IgG and EA/IgG antibodies, respectively. (Namekawa, K).

  12. Proof-of-principle that a decoy virus protects oncolytic measles virus against neutralizing antibodies

    OpenAIRE

    Xu C; Goß AV; Dorneburg C; Debatin KM; Wei J; Beltinger C

    2018-01-01

    Chun Xu,1,2,* Annika Verena Goß,1,* Carmen Dorneburg,1 Klaus-Michael Debatin,1 Jiwu Wei,2 Christian Beltinger1 1Department of Pediatrics and Adolescent Medicine, Section of Experimental Pediatric Oncology, University Medical Center Ulm, Ulm, Germany; 2Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, China *These authors contributed equally to this work Background: Attenuated oncolytic measles virus (OMV) is a promising antitumor agent in early-phase cl...

  13. Structures of Ebola virus GP and sGP in complex with therapeutic antibodies.

    Science.gov (United States)

    Pallesen, Jesper; Murin, Charles D; de Val, Natalia; Cottrell, Christopher A; Hastie, Kathryn M; Turner, Hannah L; Fusco, Marnie L; Flyak, Andrew I; Zeitlin, Larry; Crowe, James E; Andersen, Kristian G; Saphire, Erica Ollmann; Ward, Andrew B

    2016-08-08

    The Ebola virus (EBOV) GP gene encodes two glycoproteins. The major product is a soluble, dimeric glycoprotein (sGP) that is secreted abundantly. Despite the abundance of sGP during infection, little is known regarding its structure or functional role. A minor product, resulting from transcriptional editing, is the transmembrane-anchored, trimeric viral surface glycoprotein (GP). GP mediates attachment to and entry into host cells, and is the intended target of antibody therapeutics. Because large portions of sequence are shared between GP and sGP, it has been hypothesized that sGP may potentially subvert the immune response or may contribute to pathogenicity. In this study, we present cryo-electron microscopy structures of GP and sGP in complex with GP-specific and GP/sGP cross-reactive antibodies undergoing human clinical trials. The structure of the sGP dimer presented here, in complex with both an sGP-specific antibody and a GP/sGP cross-reactive antibody, permits us to unambiguously assign the oligomeric arrangement of sGP and compare its structure and epitope presentation to those of GP. We also provide biophysical evaluation of naturally occurring GP/sGP mutations that fall within the footprints identified by our high-resolution structures. Taken together, our data provide a detailed and more complete picture of the accessible Ebolavirus glycoprotein landscape and a structural basis to evaluate patient and vaccine antibody responses towards differently structured products of the GP gene.

  14. Application of solid-phase radioimmunoassay in determining antibodies to Aujeszky's disease virus in blood serum of vaccinated pigs

    International Nuclear Information System (INIS)

    Rodak, L.; Smid, B.; Valicek, L.

    1983-01-01

    In the blood sera of pigs vaccinated with inactivated vaccines manufactured by three different manufacturers the RIA method was used to determine the specific antibodies to the virus of Aujeszky's disease. In certain groups of vaccinated pigs the results of the RIA examination are unfavourably affected by the bond of antibodies to the cellular antigenous determinants. This proves that following vaccination antibodies are formed not only against the viral antigen but also against the antigens of cells on which the vaccination virus is propagated. These shortcomings are eliminated by the use of suitable cellular cultures for the preparation of viral and control antigens. Antigens are applicable for RIA and for ELISA examinations of blood sera of infected and vaccinated pigs. The advantages are described of the RIA and ELISA methods as compared with the virus neutralization test. (author)

  15. Application of solid-phase radioimmunoassay in determining antibodies to Aujeszky's disease virus in blood serum of vaccinated pigs

    Energy Technology Data Exchange (ETDEWEB)

    Rodak, L; Smid, B; Valicek, L [Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia)

    1983-11-01

    In the blood sera of pigs vaccinated with inactivated vaccines manufactured by three different manufacturers the RIA method was used to determine the specific antibodies to the virus of Aujeszky's disease. In certain groups of vaccinated pigs the results of the RIA examination are unfavourably affected by the bond of antibodies to the cellular antigenous determinants. This proves that following vaccination antibodies are formed not only against the viral antigen but also against the antigens of cells on which the vaccination virus is propagated. These shortcomings are eliminated by the use of suitable cellular cultures for the preparation of viral and control antigens. Antigens are applicable for RIA and for ELISA examinations of blood sera of infected and vaccinated pigs. The advantages are described of the RIA and ELISA methods as compared with the virus neutralization test.

  16. Screening for antibodies against Aleutian disease virus (ADV) in mink. Elucidation of dubious results by additive counterimmunoelectrophoresis

    DEFF Research Database (Denmark)

    Uttenthal, Åse

    1992-01-01

    In order to distinguish true positive results in counterimmunoelectrophoresis from false positive ones an additive counterimmunoelectrophoresis was developed. The method was tested on selected mink serum samples as part of a routine testing for antibodies towards Aleutian disease virus on 3 million...... blood samples. The procedure of the method is, that a known positive serum sample is mixed with the patient serum to be tested. The result from a false positive sample will be one precipitin line towards virus and one nonspecific line. If the serum sample is a true positive one, the antibodies...... originating from the patient serum will be added to the antibodies in the standard positive serum giving only one precipitin line. The system is further extended by testing the serum samples towards an antigen preparation containing all the cellular components but free from virus....

  17. The production of antibody by invading B cells is required for the clearance of rabies virus from the central nervous system.

    Directory of Open Access Journals (Sweden)

    D Craig Hooper

    2009-10-01

    Full Text Available The pathogenesis of rabies is associated with the inability to deliver immune effectors across the blood-brain barrier and to clear virulent rabies virus from CNS tissues. However, the mechanisms that facilitate immune effector entry into CNS tissues are induced by infection with attenuated rabies virus.Infection of normal mice with attenuated rabies virus but not immunization with killed virus can promote the clearance of pathogenic rabies virus from the CNS. T cell activity in B cell-deficient mice can control the replication of attenuated virus in the CNS, but viral mRNA persists. Low levels of passively administered rabies virus-neutralizing antibody reach infected cells in the cerebellum of B cell-deficient mice but are not sufficient to mediate virus clearance. Production of rabies virus-specific antibody by B cells invading CNS tissues is required for this process, and a substantial proportion of the B cells that accumulate in the CNS of mice infected with attenuated rabies virus produce virus-specific antibodies.The mechanisms required for immune effectors to enter rabies virus-infected tissues are induced by infection with attenuated rabies virus but not by infection with pathogenic rabies viruses or immunization with killed virus. T cell activities can inhibit rabies virus replication, but the production of rabies virus-specific antibodies by infiltrating B cells, as opposed to the leakage of circulating antibody across the BBB, is critical to elimination of the virus. These findings suggest that a pathogenic rabies virus infection may be treatable after the virus has reached the CNS tissues, providing that the appropriate immune effectors can be targeted to the infected tissues.

  18. Prevalence of Anti-Hepatitis E Virus Antibodies and First Detection of Hepatitis E Virus in Wild Boar in Slovenia.

    Science.gov (United States)

    Žele, Diana; Barry, Aline F; Hakze-van der Honing, Renate W; Vengušt, Gorazd; van der Poel, Wim H M

    2016-01-01

    Hepatitis E is an emerging zoonotic disease caused by hepatitis E virus (HEV). In this study, we investigated HEV presence in a wild boar (Sus scrofa) population of Slovenia. A total of 288 wild boar serum samples were collected throughout the country, and HEV infection was investigated by serology, using enzyme-linked immunosorbent assay (ELISA) and by HEV RNA detection using a real-time PCR assay. Antibodies against HEV were detected in 30.2% (87/288) of animals tested, whereas HEV RNA was detected in only one sample. This is the first evidence of HEV presence in the wild boar population in Slovenia, and these results suggest that these animals are part of the HEV epidemiological cycle in the country.

  19. 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

    2009-11-01

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

  20. Serotype Specificity of Antibodies against Foot-and-Mouth Disease Virus in Cattle in Selected Districts in Uganda

    DEFF Research Database (Denmark)

    Mwiine, F.N.; Ayebazibwe, C.; Olaho-Mukani, W.

    2010-01-01

    Uganda had an unusually large number of foot-and-mouth disease (FMD) outbreaks in 2006, and all clinical reports were in cattle. A serological investigation was carried out to confirm circulating antibodies against foot-and-mouth disease virus (FMDV) by ELISA for antibodies against non-structural......Uganda had an unusually large number of foot-and-mouth disease (FMD) outbreaks in 2006, and all clinical reports were in cattle. A serological investigation was carried out to confirm circulating antibodies against foot-and-mouth disease virus (FMDV) by ELISA for antibodies against non......-structural proteins and structural proteins. Three hundred and forty-nine cattle sera were collected from seven districts in Uganda, and 65% of these were found positive for antibodies against the non-structural proteins of FMDV. A subset of these samples were analysed for serotype specificity of the identified...... antibodies. High prevalences of antibodies against non-structural proteins and structural proteins of FMDV serotype O were demonstrated in herds with typical visible clinical signs of FMD, while prevalences were low in herds without clinical signs of FMD. Antibody titres were higher against serotype O than...

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

    Directory of Open Access Journals (Sweden)

    Nicole J Moreland

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

  2. Characterization of polyclonal antibodies against nonstructural protein 9 from the porcine reproductive and respiratory syndrome virus

    Directory of Open Access Journals (Sweden)

    Mengmeng ZHAO,Juanjuan QIAN,Jiexiong XIE,Tiantian CUI,Songling FENG,Guoqiang WANG,Ruining WANG,Guihong ZHANG

    2016-06-01

    Full Text Available Porcine reproductive and respiratory syndrome (PRRS is considered to be one of the most important infectious diseases impacting the swine industry and is characterized by reproductive failure in late term gestation in sows and respiratory disease in pigs of all ages. The nonstructural protein 9 gene, Nsp9, encoding the RNA-dependent RNA polymerase, is generally regarded as fairly conserved when compared to other viral proteins. Antibodies against Nsp9 will be of great importance for the diagnosis and treatment of the causal agent, PRRS virus. A study was undertaken to generate polyclonal antibodies against the immunodominant Nsp9. For this purpose, the Nsp9 was expressed in Escherichia coli and subsequently used as an antigen to immunize New Zealand rabbits. Antiserum was identified via an indirect ELISA, and then verified based on the ability to react with both naturally and artificially expressed Nsp9. Results of virus neutralization test showed that this antiserum could not neutralize the PRRSV. Nevertheless, this antiserum as a diagnostic core reagent should prove invaluable for further investigations into the mechanism of PRRS pathogenesis.

  3. Human Immunodeficiency Virus Proteins Mimic Human T Cell Receptors Inducing Cross-Reactive Antibodies

    Directory of Open Access Journals (Sweden)

    Robert Root-Bernstein

    2017-10-01

    Full Text Available Human immunodeficiency virus (HIV hides from the immune system in part by mimicking host antigens, including human leukocyte antigens. It is demonstrated here that HIV also mimics the V-β-D-J-β of approximately seventy percent of about 600 randomly selected human T cell receptors (TCR. This degree of mimicry is greater than any other human pathogen, commensal or symbiotic organism studied. These data suggest that HIV may be evolving into a commensal organism just as simian immunodeficiency virus has done in some types of monkeys. The gp120 envelope protein, Nef protein and Pol protein are particularly similar to host TCR, camouflaging HIV from the immune system and creating serious barriers to the development of safe HIV vaccines. One consequence of HIV mimicry of host TCR is that antibodies against HIV proteins have a significant probability of recognizing the corresponding TCR as antigenic targets, explaining the widespread observation of lymphocytotoxic autoantibodies in acquired immunodeficiency syndrome (AIDS. Quantitative enzyme-linked immunoadsorption assays (ELISA demonstrated that every HIV antibody tested recognized at least one of twelve TCR, and as many as seven, with a binding constant in the 10−8 to 10−9 m range. HIV immunity also affects microbiome tolerance in ways that correlate with susceptibility to specific opportunistic infections.

  4. Epitope Sequences in Dengue Virus NS1 Protein Identified by Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Leticia Barboza Rocha

    2017-10-01

    Full Text Available Dengue nonstructural protein 1 (NS1 is a multi-functional glycoprotein with essential functions both in viral replication and modulation of host innate immune responses. NS1 has been established as a good surrogate marker for infection. In the present study, we generated four anti-NS1 monoclonal antibodies against recombinant NS1 protein from dengue virus serotype 2 (DENV2, which were used to map three NS1 epitopes. The sequence 193AVHADMGYWIESALNDT209 was recognized by monoclonal antibodies 2H5 and 4H1BC, which also cross-reacted with Zika virus (ZIKV protein. On the other hand, the sequence 25VHTWTEQYKFQPES38 was recognized by mAb 4F6 that did not cross react with ZIKV. Lastly, a previously unidentified DENV2 NS1-specific epitope, represented by the sequence 127ELHNQTFLIDGPETAEC143, is described in the present study after reaction with mAb 4H2, which also did not cross react with ZIKV. The selection and characterization of the epitope, specificity of anti-NS1 mAbs, may contribute to the development of diagnostic tools able to differentiate DENV and ZIKV infections.

  5. Human broadly neutralizing antibodies to the envelope glycoprotein complex of hepatitis C virus

    DEFF Research Database (Denmark)

    Giang, Erick; Dorner, Marcus; Prentoe, Jannick C

    2012-01-01

    , and an effective vaccine should target conserved T- and B-cell epitopes of the virus. Conserved B-cell epitopes overlapping the CD81 receptor-binding site (CD81bs) on the E2 viral envelope glycoprotein have been reported previously and provide promising vaccine targets. In this study, we isolated 73 human m......Abs recognizing five distinct antigenic regions on the virus envelope glycoprotein complex E1E2 from an HCV-immune phage-display antibody library by using an exhaustive-panning strategy. Many of these mAbs were broadly neutralizing. In particular, the mAb AR4A, recognizing a discontinuous epitope outside the CD81......bs on the E1E2 complex, has an exceptionally broad neutralizing activity toward diverse HCV genotypes and protects against heterologous HCV challenge in a small animal model. The mAb panel will be useful for the design and development of vaccine candidates to elicit broadly neutralizing antibodies...

  6. Seroprevalence of anti-hepatitis E virus antibodies in domestic pigs in Mexico.

    Science.gov (United States)

    García-Hernández, Montserrat Elemi; Cruz-Rivera, Mayra; Sánchez-Betancourt, José Iván; Rico-Chávez, Oscar; Vergara-Castañeda, Arely; Trujillo, María E; Sarmiento-Silva, Rosa Elena

    2017-09-21

    Hepatitis E virus (HEV) infection is one of the most common causes of acute liver diseases in humans worldwide. In developing countries, HEV is commonly associated with waterborne outbreaks. Conversely, in industrialized countries, HEV infection is often associated with travel to endemic regions or ingestion of contaminated animal products. Limited information on both, human and animal HEV infection in Mexico is available. As a consequence, the distribution of the virus in the country is largely unknown. Here, we assessed the seroprevalence of HEV among swine in different geographical regions in Mexico. Seroprevalence of anti-HEV antibodies in swine herds in Mexico was evaluated in a representative sample including 945 pig serum specimens from different regions of the country using a commercial enzyme-linked immunosorbent assay (ELISA). The overall prevalence of anti-HEV antibodies in swine was 59.4%. The northern region of Mexico exhibited the highest seroprevalence in the country (86.6%), while the central and southern regions in Mexico showed lower seroprevalence, 42.7% and 51.5%, respectively. In Mexico, HEV seroprevalence in swine is high. Importantly, northern Mexico showed the highest seroprevalence in the country. Thus, further studies are required to identify the risk factors contributing to HEV transmission among pigs in the country. Assessment of HEV human infection in the context of viral transmission in swine is required to better understand the epidemiology of hepatitis E in Mexico.

  7. Occurrence of West Nile Virus Antibodies in Wild Birds, Horses, and Humans in Poland

    Directory of Open Access Journals (Sweden)

    Jowita Samanta Niczyporuk

    2015-01-01

    Full Text Available Serum samples of 474 wild birds, 378 horses, and 42 humans with meningitis and lymphocytic meningitis were collected between 2010 and 2014 from different areas of Poland. West Nile virus (WNV antibodies were detected using competition enzyme linked immunosorbent assays: ELISA-1 ID Screen West Nile Competition, IDvet, ELISA-2 ID Screen West Nile IgM Capture, and ELISA-3 Ingezim West Nile Compac. The antibodies were found in 63 (13.29% out of 474 wild bird serum samples and in one (0.26% out of 378 horse serum samples. Fourteen (33.33% out of 42 sera from patients were positive against WNV antigen and one serum was doubtful. Positive samples obtained in birds were next retested with virus microneutralisation test to confirm positive results and cross-reactions with other antigens of the Japanese encephalitis complex. We suspect that positive serological results in humans, birds, and horses indicate that WNV can be somehow closely related with the ecosystem in Poland.

  8. Rabies Virus Antibodies from Oral Vaccination as a Correlate of Protection against Lethal Infection in Wildlife

    Directory of Open Access Journals (Sweden)

    Susan M. Moore

    2017-07-01

    Full Text Available Both cell-mediated and humoral immune effectors are important in combating rabies infection, although the humoral response receives greater attention regarding rabies prevention. The principle of preventive vaccination has been adopted for strategies of oral rabies vaccination (ORV of wildlife reservoir populations for decades to control circulation of rabies virus in free-ranging hosts. There remains much debate about the levels of rabies antibodies (and the assays to measure them that confer resistance to rabies virus. In this paper, data from published literature and our own unpublished animal studies on the induction of rabies binding and neutralizing antibodies following oral immunization of animals with live attenuated or recombinant rabies vaccines, are examined as correlates of protection against lethal rabies infection in captive challenge settings. Analysis of our studies suggests that, though serum neutralization test results are expected to reflect in vivo protection, the blocking enzyme linked immunosorbent assay (ELISA result at Day 28 was a better predictor of survival. ELISA kits may have an advantage of greater precision and ability to compare results among different studies and laboratories based on the inherent standardization of the kit format. This paper examines current knowledge and study findings to guide meaningful interpretation of serology results in oral baiting monitoring.

  9. A case of MOG antibody-positive bilateral optic neuritis and meningoganglionitis following a genital herpes simplex virus infection.

    Science.gov (United States)

    Nakamura, Masataka; Iwasaki, Yuko; Takahashi, Toshiyuki; Kaneko, Kimihiko; Nakashima, Ichiro; Kunieda, Takenobu; Kaneko, Satoshi; Kusaka, Hirofumi

    2017-10-01

    Myelin oligodendrocyte glycoprotein (MOG) antibody-positive optic neuritis (ON) and myelitis are recognized as important differential diagnosis of aquaporin-4 (AQP4) antibody-positive neuromyelitis optica (NMO)/NMO spectrum disorder (NMOSD). Similar to NMO/NMOSD associated with AQP4 antibodies, preceding infections have been reported in patients with MOG antibody-positive ON. This is the first report of bilateral ON following a herpes simplex virus (HSV) infection associated with a positive MOG antibody. A 41-year-old man who initially presented with genital herpes developed allodynia in the Th2-Th5 and Th8-L2 areas, urinary retention, and painful visual loss in the left eye. Ophthalmological evaluation and brain magnetic resonance imaging (MRI) revealed bilateral ON. A spinal MRI showed leptomeningeal enhancement from the thoracic to lumbar vertebrae and abnormal enhancement of the L3 to S3 dorsal root ganglia without a change in intramedullary signals. Following treatment with acyclovir and steroid pulse, he fully recovered. Serum anti-AQP4 antibodies were negative, but anti-MOG antibodies were positive. Finally, he was diagnosed with MOG antibody-positive bilateral ON and meningoganglionitis following an HSV infection. Our case supports a relationship between anti-MOG antibodies and ON triggered by an HSV infection. Clinicians should thus consider testing for MOG antibodies in patients with post-infectious neurological symptoms due to an HSV infection. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Study of the titers of Anti-Epstein-Barr virus antibodies in the sera of atomic bomb survivors

    International Nuclear Information System (INIS)

    Akiyama, Mitoshi; Kusunoki, Yoichiro; Kyoizumi, Seishi; Ozaki, Kyoko; Mizuno, Shoichi; Cologne, J.B.

    1993-01-01

    Antibody titers to Epstein-Barr virus antigens were determined in the sera of 372 atomic bomb survivors to evaluate the effect of the previous radiation exposure on immune competence against the latent infection of the virus. The proportion of persons with high titers (≥ 1:40) of IgG antibodies to the early antigen was significantly elevated in the exposed survivors. Furthermore, the distribution of IgM titers against the viral capsid antigen was significantly affected by radiation dose with an increased occurrence of titers of 1:5 and 1:10 in the exposed persons, although the dose effect was only marginally suggestive when persons with rheumatoid factor were eliminated from the analysis. These results suggest that reactivation of Epstein-Barr virus in the latent stage occurs more frequently in the survivors, even though this might not be affected by the radiation dose. Otherwise, there was neither an increased trend in the prevalence of high titers (≥ 1:640) of IgG antibodies to the viral capsid antigen among the exposed people nor a correlation between the radiation exposure and distributions of titers of IgA antibodies to the viral capsid antigen or antibodies to the anti-Epstein-Barr virus-associated nuclear antigen. (author)

  11. Study of the titers of Anti-Epstein-Barr virus antibodies in the sera of atomic bomb survivors

    Energy Technology Data Exchange (ETDEWEB)

    Akiyama, Mitoshi; Kusunoki, Yoichiro; Kyoizumi, Seishi; Ozaki, Kyoko; Mizuno, Shoichi; Cologne, J.B.

    1993-12-31

    Antibody titers to Epstein-Barr virus antigens were determined in the sera of 372 atomic bomb survivors to evaluate the effect of the previous radiation exposure on immune competence against the latent infection of the virus. The proportion of persons with high titers ({>=} 1:40) of IgG antibodies to the early antigen was significantly elevated in the exposed survivors. Furthermore, the distribution of IgM titers against the viral capsid antigen was significantly affected by radiation dose with an increased occurrence of titers of 1:5 and 1:10 in the exposed persons, although the dose effect was only marginally suggestive when persons with rheumatoid factor were eliminated from the analysis. These results suggest that reactivation of Epstein-Barr virus in the latent stage occurs more frequently in the survivors, even though this might not be affected by the radiation dose. Otherwise, there was neither an increased trend in the prevalence of high titers ({>=} 1:640) of IgG antibodies to the viral capsid antigen among the exposed people nor a correlation between the radiation exposure and distributions of titers of IgA antibodies to the viral capsid antigen or antibodies to the anti-Epstein-Barr virus-associated nuclear antigen. (author).

  12. Neutralizing antibody response during human immunodeficiency virus type 1 infection: type and group specificity and viral escape

    DEFF Research Database (Denmark)

    Arendrup, M; Sönnerborg, A; Svennerholm, B

    1993-01-01

    The paradox that group-specific neutralizing antibodies (NA) exist in the majority of human immunodeficiency virus type 1 (HIV-1)-infected patients, whereas the NA response against autologous HIV-1 virus isolates is highly type-specific, motivated us to study the type- and group-specific NA...... demonstrated, suggesting that the majority of the change in neutralization sensitivity is driven by the selective pressure of type-specific NA. Furthermore, no differences were observed in sensitivity to neutralization by anti-carbohydrate neutralizing monoclonal antibodies or the lectin concanavalin A...

  13. Dengue, Japanese encephalitis and Chikungunya virus antibody prevalence among captive monkey (Macaca nemestrina) colonies of Northern Thailand.

    Science.gov (United States)

    Nakgoi, Khajornpong; Nitatpattana, Narong; Wajjwalku, Worawidh; Pongsopawijit, Pornsawan; Kaewchot, Supakarn; Yoksan, Sutee; Siripolwat, Voravit; Souris, Marc; Gonzalez, Jean-Paul

    2014-01-01

    The potential of macaque Macaca nemestrina leonina in Thailand to be infected by endemic arboviruses was assessed. The prevalence of antibodies of three arboviruses actively circulating in Thailand was determined by Plaque Reduction Neutralization assay procedures using samples from captive colonies in Northern Thailand. Out of 38 macaques, 9 (24%) presented reacting antibodies against dengue virus, 5 (13%) against Japanese encephalitis virus, and 4 (10%) against Chikungunya virus. Our results indicate that the northern pig-tailed macaque in Thailand can be infected by these arboviruses, inferring therefore that their virus specific vectors have bitten them. Given that, northern pig-tailed macaque represents an abundant population, living in close range to human or in peridomestic setting, they could play a role as potential reservoir host for arboviruses circulating in Thailand. © 2013 Wiley Periodicals, Inc.

  14. Development and clinical applications of novel antibodies for prevention and treatment of respiratory syncytial virus infection.

    Science.gov (United States)

    Mejias, Asuncion; Garcia-Maurino, Cristina; Rodriguez-Fernandez, Rosa; Peeples, Mark E; Ramilo, Octavio

    2017-01-11

    Respiratory syncytial virus (RSV) remains a significant cause of morbidity and mortality in infants and young children, immunocompromised patients and the elderly. Despite the high disease burden, an effective and safe vaccine is lacking, although several candidates are currently in development. Current treatment for RSV infection remains largely supportive and RSV-specific options for prophylaxis are limited to palivizumab. In the past few years, novel therapeutic options including nanobodies, polyclonal and monoclonal antibodies have emerged and there are several products in preclinical and Phase-I, -II or -III clinical trials. The major target for antiviral drug development is the surface fusion (F) glycoprotein, which is crucial for the infectivity and pathogenesis of the virus. Solving the structures of the two conformations of the RSV F protein, the prefusion and postfusion forms, has revolutionized RSV research. It is now known that prefusion F is highly superior in inducing neutralizing antibodies. In this section we will review the stages of development and availability of different antibodies directed against RSV for the prevention and also for treatment of acute RSV infections. Some of these newer anti-RSV agents have shown enhanced potency, are being explored through alternative routes of administration, have improved pharmacokinetic profiles with an extended half-life, and may reduce design and manufacturing costs. Management strategies will require targeting not only high-risk populations (including adults or immunocompromised patients), but also previously healthy children who, in fact, represent the majority of children hospitalized with RSV infection. Following treated patients longitudinally is essential for determining the impact of these strategies on the acute disease as well as their possible long-term benefits on lung morbidity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Antibodies to the HFRS virus in the human population of European RSFSR as detected by radioimmunoassay

    International Nuclear Information System (INIS)

    Myasnikov, Y.A.; Rezapkin, G.V.; Shuikova, Z.V.; Tkachenko, E.A.; Ivanova, A.A.; Nurgaleeva, R.G.; Stepanenko, A.G.; Vereshchagin, N.N.; Loginov, A.I.; Bagan, R.N.; Zaitseva, A.A.; Levacheva, Z.A.; Bobylkova, T.V.; Ishcheryakova, A.M.; Boruta, V.V.

    1984-01-01

    Natural immunity to the causative agent of hemorrhagic fever with renal syndrome (HFRS) has first been studied using radioimmunoassay (RIA) in the human population of the Bashkir ASSR with the highest incidence of this infection and of five other regions of the RSFSR with lower incidence of HFRS. The antigen was prepared as a suspension of lungs of rodent from natural HFRS foci and contained a high concentration of virus protein. 12000 sera from the population of 6 areas of the RSFSR were examined. In the Bashkir ASSR antibodies were detected in 13.7 per cent of the subjects examined, this figure varying in different districts from 4.0 to 41.5 per cent. In the other areas the portion of immune subjects varied from 6.7 per cent in Kuybyshev region to 1.6 per cent in Vladimir region. No correlation between the size of the immune portion of the population and average incidence rates for 5 years was observed. In Bashkiriya, immunity was found in 14.9 per cent of men and 11.8 per cent of women. In other regions, the per cent of women with antibodies to HFRS virus was also lower. In the age-group under 40 the percentage of immunity was lower (11.4 per cent) than in older age-groups (17.4 per cent). The portion of immune subjects varied in different occupation groups. In HFRS convalescents the antibody was found to persist in high titre for 20 years (the observation period). (Author)

  16. Antibody-mediated neutralization of Ebola virus can occur by two distinct mechanisms

    International Nuclear Information System (INIS)

    Shedlock, Devon J.; Bailey, Michael A.; Popernack, Paul M.; Cunningham, James M.; Burton, Dennis R.; Sullivan, Nancy J.

    2010-01-01

    Human Ebola virus causes severe hemorrhagic fever disease with high mortality and there is no vaccine or treatment. Antibodies in survivors occur early, are sustained, and can delay infection when transferred into nonhuman primates. Monoclonal antibodies (mAbs) from survivors exhibit potent neutralizing activity in vitro and are protective in rodents. To better understand targets and mechanisms of neutralization, we investigated a panel of mAbs shown previously to react with the envelope glycoprotein (GP). While one non-neutralizing mAb recognized a GP epitope in the nonessential mucin-like domain, the rest were specific for GP1, were neutralizing, and could be further distinguished by reactivity with secreted GP. We show that survivor antibodies, human KZ52 and monkey JP3K11, were specific for conformation-dependent epitopes comprising residues in GP1 and GP2 and that neutralization occurred by two distinct mechanisms; KZ52 inhibited cathepsin cleavage of GP whereas JP3K11 recognized the cleaved, fusion-active form of GP.

  17. The effect of prior transfusion history on blood donor anti-hepatitis C virus antibody.

    Science.gov (United States)

    Mazda, T; Nakata, K; Ota, K; Kaminuma, Y; Katayama, T

    1993-01-01

    In Japan, the major transfusion-associated disease is non-A, non-B hepatitis. We studied the relationship between transfusion history and blood donor antibodies to hepatitis C virus (HCV). The positive rate of antibodies to the HCV nonstructural protein (c100-3) depended on age and the time elapsed since transfusion. The anti-c100-3 ratio for subjects with transfusions made prior to 20 years ago was high. One quarter century ago, a change occurred in national blood policy from paid to non-paid voluntary donations. We also have studied the anti-HCV positive rate among donors with prior transfusion using a second generation HCV test kit which includes anti-HCV core antibody detection. The anti-HCV positive rate for the second generation test was higher than that for the anti-c100-3 test. Introduction of the second generation test is therefore more useful in screening than the anti-c100-3 test for blood programs.

  18. Fitness landscape of the human immunodeficiency virus envelope protein that is targeted by antibodies

    Science.gov (United States)

    Louie, Raymond H. Y.; Kaczorowski, Kevin J.; Chakraborty, Arup K.; McKay, Matthew R.

    2018-01-01

    HIV is a highly mutable virus, and over 30 years after its discovery, a vaccine or cure is still not available. The isolation of broadly neutralizing antibodies (bnAbs) from HIV-infected patients has led to renewed hope for a prophylactic vaccine capable of combating the scourge of HIV. A major challenge is the design of immunogens and vaccination protocols that can elicit bnAbs that target regions of the virus’s spike proteins where the likelihood of mutational escape is low due to the high fitness cost of mutations. Related challenges include the choice of combinations of bnAbs for therapy. An accurate representation of viral fitness as a function of its protein sequences (a fitness landscape), with explicit accounting of the effects of coupling between mutations, could help address these challenges. We describe a computational approach that has allowed us to infer a fitness landscape for gp160, the HIV polyprotein that comprises the viral spike that is targeted by antibodies. We validate the inferred landscape through comparisons with experimental fitness measurements, and various other metrics. We show that an effective antibody that prevents immune escape must selectively bind to high escape cost residues that are surrounded by those where mutations incur a low fitness cost, motivating future applications of our landscape for immunogen design. PMID:29311326

  19. Torque Teno Virus Load-Inverse Association With Antibody-Mediated Rejection After Kidney Transplantation.

    Science.gov (United States)

    Schiemann, Martin; Puchhammer-Stöckl, Elisabeth; Eskandary, Farsad; Kohlbeck, Philip; Rasoul-Rockenschaub, Susanne; Heilos, Andreas; Kozakowski, Nicolas; Görzer, Irene; Kikić, Željko; Herkner, Harald; Böhmig, Georg A; Bond, Gregor

    2017-02-01

    Antibody-mediated rejection (AMR) represents one of the cardinal causes of late allograft loss after kidney transplantation, and there is great need for noninvasive tools improving early diagnosis of this rejection type. One promising strategy might be the quantification of peripheral blood DNA levels of the highly prevalent and apathogenic Torque Teno virus (TTV), which might mirror the overall level of immunosuppression and thus help determine the risk of alloimmune response. To assess the association between TTV load in the peripheral blood and AMR, 715 kidney transplant recipients (median, 6.3 years posttransplantation) were subjected to a systematical cross-sectional AMR screening and, in parallel, TTV quantification. Eighty-six of these recipients had donor-specific antibodies and underwent protocol biopsy, AMR-positive patients (n = 46) showed only 25% of the TTV levels measured in patients without AMR (P = 0.003). In a generalized linear model, higher TTV levels were associated with a decreased risk for AMR after adjustment for potential confounders (risk ratio 0.94 per TTV log level; 95% confidence interval 0.90-0.99; P = 0.02). Future studies will have to clarify whether longitudinal assessment of TTV load might predict AMR risk and help guide the type and intensity of immunosuppression to prevent antibody-mediated graft injury.

  20. Hepatitis C Virus Antibodies in Dialysis Patients in Tunisia: A Single Center Study

    Directory of Open Access Journals (Sweden)

    Sassi F

    2000-01-01

    Full Text Available Fifty-eight patients on maintenance hemodialysis in a dialysis unit at Tunis, Tunisia were tested for anti-hepatitis C virus (anti-HCV antibodies by second generation ELISA test, and for HCV-RNA by nested reverse transcriptase polymerase chain reaction (RT-PCR of 5′ non-coding region. Specificity of the antibodies was confirmed by immunoblot test. HCV genotype was defined using INNO-LIPA test. Twenty-seven out of 58 patients (46.5% were reactive by ELISA. Transaminase levels were assessed over a six-month period and showed normal average values. Fourteen of the 27 anti-HCV positive patients (51% were positive by RT-PCR. Type 1b HCV genotype was the most prevalent, seen in all the dialysis patients and one patient in addition, was co-infected with genotype 4. There was a significant correlation between the duration on dialysis (over five years and the prevalence of anti-HCV-positive patients (P< 0.005 while no correlation existed between the number of blood transfusions and the presence of anti-HCV antibodies. The present study illustrates the high prevalence of HCV infection among Tunisian dialysis patients (51% and indicates that the spread may be nosocomial rather than transfusion-related.

  1. Broad neutralizing human monoclonal antibodies against influenza virus from vaccinated healthy donors

    Energy Technology Data Exchange (ETDEWEB)

    Kubota-Koketsu, Ritsuko; Mizuta, Hiroyuki [Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871 (Japan); Oshita, Masatoshi; Ideno, Shoji [Osaka Research Laboratory, Benesis Corporation, Yodogawa-ku, Osaka 532-6505 (Japan); Yunoki, Mikihiro [Osaka Research Laboratory, Benesis Corporation, Yodogawa-ku, Osaka 532-6505 (Japan); Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871 (Japan); Kuhara, Motoki [Ina Laboratory, Medical and Biological Laboratories Corporation, Ltd., Ina, Nagano 396-0002 (Japan); Yamamoto, Naomasa [Department of Biochemistry, School of Pharmaceutical Sciences, Ohu University, Koriyama, Fukushima 963-8611 (Japan); Okuno, Yoshinobu [Kanonji Institute, The Research Foundation for Microbial Diseases of Osaka University, Kanonji, Kagawa 768-0061 (Japan); Ikuta, Kazuyoshi, E-mail: ikuta@biken.osaka-u.ac.jp [Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871 (Japan)

    2009-09-11

    Human monoclonal antibodies (HuMAbs) prepared from patients with viral infections could provide information on human epitopes important for the development of vaccines as well as potential therapeutic applications. Through the fusion of peripheral blood mononuclear cells from a total of five influenza-vaccinated volunteers, with newly developed murine-human chimera fusion partner cells, named SPYMEG, we obtained 10 hybridoma clones stably producing anti-influenza virus antibodies: one for influenza A H1N1, four for influenza A H3N2 and five for influenza B. Surprisingly, most of the HuMAbs showed broad reactivity within subtype and four (two for H3N2 and two for B) showed broad neutralizing ability. Importantly, epitope mapping revealed that the two broad neutralizing antibodies to H3N2 derived from different donors recognized the same epitope located underneath the receptor-binding site of the hemagglutinin globular region that is highly conserved among H3N2 strains.

  2. Comparison of immunoassays for differentiation of herpes simplex virus type 1 and 2 antibodies

    International Nuclear Information System (INIS)

    Klapper, Paul E.; Valley, Pam J.; Cleator, Gerham M.; Mandall, D.; Qutub, Mohammed O.

    2006-01-01

    To asses the commercial available enzyme-linked immunosorbent assays (ELISA) for differentiation of herpes simplex virus type 1 (Hs-1) and type 2 (HSV-2) antibodies. The study was performed between January 1997 to November 2002 in the Division ofVirology,Department of Pathological Sciences, Central Manchester Healthcare Trust and University of Manchester, Manchester, United Kingdom. Assays based upon type-specific glycoprotein G-1 (gG-1) for HSV-1, and glycoprotein G-2 (gG-2) from HSV-2 were evaluated to differentiate between HSV-1 and HSV-2 antibodies. Using 5 different ELISA tests, 2 panels of serum samples were tested. Panel one consisted of 88 sera, selected from the serum bank of the Clinical Virology Laboratory, Manchester Royal Infirmary; panel 2 comprised of 90 sera selected from samples collected from Bangladeshi female commercial workers.The data of this study showed that a high rate of gG-1 based immunoassays ranged from 87.9-100% for sensitivity and 51.5-100% specificity. Although there are several immunoassays were claimed to differentiate between HSV-1 and HSV-2 antibodies, selection of these assays should be carefully interpreted with the overall clinical framework provided by detailed sexual history and genital examination. (author)

  3. Broad neutralizing human monoclonal antibodies against influenza virus from vaccinated healthy donors

    International Nuclear Information System (INIS)

    Kubota-Koketsu, Ritsuko; Mizuta, Hiroyuki; Oshita, Masatoshi; Ideno, Shoji; Yunoki, Mikihiro; Kuhara, Motoki; Yamamoto, Naomasa; Okuno, Yoshinobu; Ikuta, Kazuyoshi

    2009-01-01

    Human monoclonal antibodies (HuMAbs) prepared from patients with viral infections could provide information on human epitopes important for the development of vaccines as well as potential therapeutic applications. Through the fusion of peripheral blood mononuclear cells from a total of five influenza-vaccinated volunteers, with newly developed murine-human chimera fusion partner cells, named SPYMEG, we obtained 10 hybridoma clones stably producing anti-influenza virus antibodies: one for influenza A H1N1, four for influenza A H3N2 and five for influenza B. Surprisingly, most of the HuMAbs showed broad reactivity within subtype and four (two for H3N2 and two for B) showed broad neutralizing ability. Importantly, epitope mapping revealed that the two broad neutralizing antibodies to H3N2 derived from different donors recognized the same epitope located underneath the receptor-binding site of the hemagglutinin globular region that is highly conserved among H3N2 strains.

  4. Anti-Hemagglutinin Antibody Derived Lead Peptides for Inhibitors of Influenza Virus Binding.

    Directory of Open Access Journals (Sweden)

    Henry Memczak

    Full Text Available Antibodies against spike proteins of influenza are used as a tool for characterization of viruses and therapeutic approaches. However, development, production and quality control of antibodies is expensive and time consuming. To circumvent these difficulties, three peptides were derived from complementarity determining regions of an antibody heavy chain against influenza A spike glycoprotein. Their binding properties were studied experimentally, and by molecular dynamics simulations. Two peptide candidates showed binding to influenza A/Aichi/2/68 H3N2. One of them, termed PeB, with the highest affinity prevented binding to and infection of target cells in the micromolar region without any cytotoxic effect. PeB matches best the conserved receptor binding site of hemagglutinin. PeB bound also to other medical relevant influenza strains, such as human-pathogenic A/California/7/2009 H1N1, and avian-pathogenic A/Mute Swan/Rostock/R901/2006 H7N1. Strategies to improve the affinity and to adapt specificity are discussed and exemplified by a double amino acid substituted peptide, obtained by substitutional analysis. The peptides and their derivatives are of great potential for drug development as well as biosensing.

  5. Molecular aspects of antibody-antigen interactions : size reduction of a herpes simplex virus neutralizing antibody and its antigen

    NARCIS (Netherlands)

    Schellekens, Gerardus Antonius

    1996-01-01

    Antibody molecules, produced as a response against foreign substances, interact with their antigen in a very specific manner. Antibodies with a predetermined specificity (monoclonal antibodies) can be produced and are widely used in medicine and science as indicator molecules. Genetic engineering of

  6. In vivo activity of a mixture of two human monoclonal antibodies (anti-HBs) in a chronic hepatitis B virus carrier chimpanzee

    NARCIS (Netherlands)

    R. Heijtink; W. Paulij; P.A.C. van Bergen (Patrick); M.H. van Roosmalen (Mark); D. Rohm; B. Eichentopf (Bertram); E. Muchmore; A.D.M.E. Osterhaus (Albert); R.A. de Man (Robert)

    1999-01-01

    textabstractA 35-year-old female hepatitis B virus carrier chimpanzee was infused with one dose of a mixture of human monoclonal antibodies 9H9 and 4-7B (antibodies against hepatitis B virus surface antigen; HBsAg). Blood samples were taken before and up to 3 weeks

  7. Hepatitis C virus expressing flag-tagged envelope protein 2 has unaltered infectivity and density, is specifically neutralized by flag antibodies and can be purified by affinity chromatography

    DEFF Research Database (Denmark)

    Prentø, Jannick Cornelius; Bukh, Jens

    2011-01-01

    to the original virus. Flag-tagged virus was susceptible to flag-specific antibody neutralization, and infected cells could be immuno-stained by anti-flag antibodies. Using affinity chromatography with anti-flag resin we repeatedly obtained ~30% recovery of infectious particles. The full viability and unaltered...

  8. Antibodies against vesicular stomatitis virus in horses from southern, midwestern and northeastern Brazilian States

    Directory of Open Access Journals (Sweden)

    Vinícius Leobet Lunkes

    2016-08-01

    Full Text Available ABSTRACT: Vesicular stomatitis virus (VSV is the agent of a vesicular disease that affects many animal species and may be clinically confounded with foot-and-mouth disease in ruminant and swine. Horses are especially susceptible to VSV and may serve as sentinels for virus circulation. The present study investigated the presence of neutralizing antibodies against VSV Indiana III (VSIV-3 in serum samples of 3,626 horses from six states in three Brazilian regions: Southern (RS, n = 1,011, Midwest (GO/DF, n = 1,767 and Northeast (PB, PE, RN and CE, n = 848 collected between 2013 and 2014. Neutralizing antibodies against VSIV-3 (titers ≥40 were detected in 641 samples (positivity of 17.7%; CI95%:16.5-19.0%, being 317 samples from CE (87.3%; CI95%: 83.4-90.5 %; 109 from RN (65.7%; CI95%: 57.8 -72.7%; 124 from PB (45.4%; CI95%: 39.4-51.5%; 78 from GO/DF (4.4%; CI95%: 3.5-5.5% and nine samples of RS (0.9%; CI95%: 0.4-1.7%. Several samples from the Northeast and Midwest harbored high neutralizing titers, indicating a recent exposure to the virus. In contrast, samples from RS had low titers, possibly due to a past remote exposure. Several positive samples presented neutralizing activity against other VSV serotypes (Indiana I and New Jersey, yet in lower titers, indicating the specificity of the response to VSIV-3. These results demonstrated a relatively recent circulation of VSIV-3 in northeastern Brazilian States, confirming clinical findings and demonstrating the sanitary importance of this infection.

  9. Acute Hendra virus infection: Analysis of the pathogenesis and passive antibody protection in the hamster model

    International Nuclear Information System (INIS)

    Guillaume, Vanessa; Wong, K. Thong; Looi, R.Y.; Georges-Courbot, Marie-Claude; Barrot, Laura; Buckland, Robin; Wild, T. Fabian; Horvat, Branka

    2009-01-01

    Hendra virus (HeV) and Nipah virus (NiV) are recently-emerged, closely related and highly pathogenic paramyxoviruses. We have analysed here the pathogenesis of the acute HeV infection using the new animal model, golden hamster (Mesocricetus auratus), which is highly susceptible to HeV infection. HeV-specific RNA and viral antigens were found in multiple organs and virus was isolated from different tissues. Dual pathogenic mechanism was observed: parenchymal infection in various organs, including the brain, with vasculitis and multinucleated syncytia in many blood vessels. Furthermore, monoclonal antibodies specific for the NiV fusion protein neutralized HeV in vitro and efficiently protected hamsters from HeV if given before infection. These results reveal the similarities between HeV and NiV pathogenesis, particularly in affecting both respiratory and neuronal system. They demonstrate that hamster presents a convenient novel animal model to study HeV infection, opening new perspectives to evaluate vaccine and therapeutic approaches against this emergent infectious disease.

  10. Antibody study in canine distemper virus nucleocapsid protein gene-immunized mice.

    Science.gov (United States)

    Yuan, B; Li, X Y; Zhu, T; Yuan, L; Hu, J P; Chen, J; Gao, W; Ren, W Z

    2015-04-10

    The gene for the nucleocapsid (N) protein of canine distemper virus was cloned into the pMD-18T vector, and positive recombinant plasmids were obtained by enzyme digestion and sequencing. After digestion by both EcoRI and KpnI, the plasmid was directionally cloned into the eukaryotic expression vector pcDNA; the positive clone pcDNA-N was screened by electrophoresis and then transfected into COS-7 cells. Immunofluorescence analysis results showed that the canine distemper virus N protein was expressed in the cytoplasm of transfected COS-7 cells. After emulsification in Freund's adjuvant, the recombinant plasmid pcDNA-N was injected into the abdominal cavity of 8-week-old BABL/c mice, with the pcDNA original vector used as a negative control. Mice were immunized 3 times every 2 weeks. The blood of immunized mice was drawn 2 weeks after completing the immunizations to measure titer levels. The antibody titer in the pcDNA-N test was 10(1.62 ± 0.164), while in the control group this value was 10(0.52 ± 0.56), indicating that specific humoral immunity was induced in canine distemper virus nucleocapsid protein-immunized mice.

  11. Structural and Antigenic Definition of Hepatitis C Virus E2 Glycoprotein Epitopes Targeted by Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Giuseppe Sautto

    2013-01-01

    Full Text Available Hepatitis C virus (HCV is the major cause of chronic liver disease as well as the major indication for liver transplantation worldwide. Current standard of care is not completely effective, not administrable in grafted patients, and burdened by several side effects. This incomplete effectiveness is mainly due to the high propensity of the virus to continually mutate under the selective pressure exerted by the host immune response as well as currently administered antiviral drugs. The E2 envelope surface glycoprotein of HCV (HCV/E2 is the main target of the host humoral immune response and for this reason one of the major variable viral proteins. However, broadly cross-neutralizing monoclonal antibodies (mAbs directed against HCV/E2 represent a promising tool for the study of virus-host interplay as well as for the development of effective prophylactic and therapeutic approaches. In the last few years many anti-HCV/E2 mAbs have been evaluated in preclinical and clinical trials as possible candidate antivirals, particularly for administration in pre- and post-transplant settings. In this review we summarize the antigenic and structural characteristics of HCV/E2 determined through the use of anti-HCV/E2 mAbs, which, given the absence of a crystal structure of this glycoprotein, represent currently the best tool available.

  12. Neutralization resistance of hepatitis C virus can be overcome by recombinant human monoclonal antibodies

    DEFF Research Database (Denmark)

    Pedersen, Jannie L; Carlsen, Thomas H R; Prentoe, Jannick

    2013-01-01

    Immunotherapy and vaccine development for hepatitis C virus (HCV) will depend on broadly reactive neutralizing antibodies (NAbs). However, studies in infectious strain JFH1-based culture systems expressing patient-derived Core-NS2 proteins have suggested neutralization resistance for specific HCV...... demonstrated that the novel genotype 2 viruses as well as prototype strains J6/JFH1(2a) and J8/JFH1(2b), all with authentic envelope proteins, were resistant to neutralization by genotype 2a, 2b, 2c, 2j, 2i, and 2q patient sera. However, these patient sera had high titers of HCV-specific NAbs, because...... they efficiently reduced the infectivity of J6(2a) and J8(2b) with deleted hypervariable region 1. The genotype 2a, 2b, and 2c viruses, found resistant to polyclonal patient sera neutralization, were efficiently neutralized by two lead HMAbs (AR4A and HC84.26). Conclusion: Using novel 2a, 2b, and 2c cell...

  13. Antibodies to the core proteins of Nairobi sheep disease virus/Ganjam virus reveal details of the distribution of the proteins in infected cells and tissues.

    Science.gov (United States)

    Lasecka, Lidia; Bin-Tarif, Abdelghani; Bridgen, Anne; Juleff, Nicholas; Waters, Ryan A; Baron, Michael D

    2015-01-01

    Nairobi sheep disease virus (NSDV; also called Ganjam virus in India) is a bunyavirus of the genus Nairovirus. It causes a haemorrhagic gastroenteritis in sheep and goats with mortality up to 90%. The virus is closely related to the human pathogen Crimean-Congo haemorrhagic fever virus (CCHFV). Little is currently known about the biology of NSDV. We have generated specific antibodies against the virus nucleocapsid protein (N) and polymerase (L) and used these to characterise NSDV in infected cells and to study its distribution during infection in a natural host. Due to its large size and the presence of a papain-like protease (the OTU-like domain) it has been suggested that the L protein of nairoviruses undergoes an autoproteolytic cleavage into polymerase and one or more accessory proteins. Specific antibodies which recognise either the N-terminus or the C-terminus of the NSDV L protein showed no evidence of L protein cleavage in NSDV-infected cells. Using the specific anti-N and anti-L antibodies, it was found that these viral proteins do not fully colocalise in infected cells; the N protein accumulated near the Golgi at early stages of infection while the L protein was distributed throughout the cytoplasm, further supporting the multifunctional nature of the L protein. These antibodies also allowed us to gain information about the organs and cell types targeted by the virus in vivo. We could detect NSDV in cryosections prepared from various tissues collected post-mortem from experimentally inoculated animals; the virus was found in the mucosal lining of the small and large intestine, in the lungs, and in mesenteric lymph nodes (MLN), where NSDV appeared to target monocytes and/or macrophages.

  14. Antibodies to the core proteins of Nairobi sheep disease virus/Ganjam virus reveal details of the distribution of the proteins in infected cells and tissues.

    Directory of Open Access Journals (Sweden)

    Lidia Lasecka

    Full Text Available Nairobi sheep disease virus (NSDV; also called Ganjam virus in India is a bunyavirus of the genus Nairovirus. It causes a haemorrhagic gastroenteritis in sheep and goats with mortality up to 90%. The virus is closely related to the human pathogen Crimean-Congo haemorrhagic fever virus (CCHFV. Little is currently known about the biology of NSDV. We have generated specific antibodies against the virus nucleocapsid protein (N and polymerase (L and used these to characterise NSDV in infected cells and to study its distribution during infection in a natural host. Due to its large size and the presence of a papain-like protease (the OTU-like domain it has been suggested that the L protein of nairoviruses undergoes an autoproteolytic cleavage into polymerase and one or more accessory proteins. Specific antibodies which recognise either the N-terminus or the C-terminus of the NSDV L protein showed no evidence of L protein cleavage in NSDV-infected cells. Using the specific anti-N and anti-L antibodies, it was found that these viral proteins do not fully colocalise in infected cells; the N protein accumulated near the Golgi at early stages of infection while the L protein was distributed throughout the cytoplasm, further supporting the multifunctional nature of the L protein. These antibodies also allowed us to gain information about the organs and cell types targeted by the virus in vivo. We could detect NSDV in cryosections prepared from various tissues collected post-mortem from experimentally inoculated animals; the virus was found in the mucosal lining of the small and large intestine, in the lungs, and in mesenteric lymph nodes (MLN, where NSDV appeared to target monocytes and/or macrophages.

  15. Analysis of potato virus Y coat protein epitopes recognized by three commercial monoclonal antibodies.

    Science.gov (United States)

    Tian, Yan-Ping; Hepojoki, Jussi; Ranki, Harri; Lankinen, Hilkka; Valkonen, Jari P T

    2014-01-01

    Potato virus Y (PVY, genus Potyvirus) causes substantial economic losses in solanaceous plants. Routine screening for PVY is an essential part of seed potato certification, and serological assays are often used. The commercial, commonly used monoclonal antibodies, MAb1128, MAb1129, and MAb1130, recognize the viral coat protein (CP) of PVY and distinguish PVYN strains from PVYO and PVYC strains, or detect all PVY strains, respectively. However, the minimal epitopes recognized by these antibodies have not been identified. SPOT peptide array was used to map the epitopes in CP recognized by MAb1128, MAb1129, and MAb1130. Then alanine replacement as well as N- and C-terminal deletion analysis of the identified peptide epitopes was done to determine critical amino acids for antibody recognition and the respective minimal epitopes. The epitopes of all antibodies were located within the 30 N-terminal-most residues. The minimal epitope of MAb1128 was 25NLNKEK30. Replacement of 25N or 27N with alanine weakened the recognition by MAb1128, and replacement of 26L, 29E, or 30K nearly precluded recognition. The minimal epitope for MAb1129 was 16RPEQGSIQSNP26 and the most critical residues for recognition were 22I and 23Q. The epitope of MAb1130 was defined by residues 5IDAGGS10. Mutation of residue 6D abrogated and mutation of 9G strongly reduced recognition of the peptide by MAb1130. Amino acid sequence alignment demonstrated that these epitopes are relatively conserved among PVY strains. Finally, recombinant CPs were produced to demonstrate that mutations in the variable positions of the epitope regions can affect detection with the MAbs. The epitope data acquired can be compared with data on PVY CP-encoding sequences produced by laboratories worldwide and utilized to monitor how widely the new variants of PVY can be detected with current seed potato certification schemes or during the inspection of imported seed potatoes as conducted with these MAbs.

  16. Complexity of Human Antibody Response to Dengue Virus: Implication for Vaccine Development

    Directory of Open Access Journals (Sweden)

    Wen-Yang Tsai

    2017-07-01

    Full Text Available The four serotypes of dengue virus (DENV are the leading cause of arboviral diseases in humans. Decades of efforts have made remarkable progress in dengue vaccine development. Despite the first dengue vaccine (dengvaxia from Sanofi Pasteur, a live-attenuated tetravalent chimeric yellow fever-dengue vaccine, has been licensed by several countries since 2016, its overall moderate efficacy (56.5–60.8% in the presence of neutralizing antibodies during the Phase 2b and 3 trials, lower efficacy among dengue naïve compared with dengue experienced individuals, and increased risk of hospitalization among young children during the follow-up highlight the need for a better understanding of humoral responses after natural DENV infection. Recent studies of more than 300 human monoclonal antibodies (mAbs against DENV have led to the discovery of several novel epitopes on the envelope protein recognized by potent neutralizing mAbs. This information together with in-depth studies on polyclonal sera and B-cells following natural DENV infection has tremendous implications for better immunogen design for a safe and effective dengue vaccine. This review outlines the progress in our understanding of mouse mAbs, human mAbs, and polyclonal sera against DENV envelope and precursor membrane proteins, two surface proteins involved in vaccine development, following natural infection; analyses of these discoveries have provided valuable insight into new strategies involving molecular technology to induce more potent neutralizing antibodies and less enhancing antibodies for next-generation dengue vaccine development.

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

    Science.gov (United States)

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

    2015-12-01

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

  18. 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.

    Science.gov (United States)

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

    2014-12-01

    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. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Epstein-Barr virus but not cytomegalovirus is associated with reduced vaccine antibody responses in Gambian infants.

    Directory of Open Access Journals (Sweden)

    Beth Holder

    2010-11-01

    Full Text Available Epstein-Barr virus (EBV and cytomegalovirus (CMV are persistent herpesviruses that have various immunomodulatory effects on their hosts. Both viruses are usually acquired in infancy in Sub-Saharan Africa, a region where childhood vaccines are less effective than in high income settings. To establish whether there is an association between these two observations, we tested the hypothesis that infection with one or both viruses modulate antibody responses to the T-cell independent meningococcal polysaccharide vaccine and the T-cell dependent measles vaccines.Infection with EBV and CMV was diagnosed by the presence of virus-specific IgM in the peripheral blood or by the presence of IgG at higher levels than that found in umbilical cord blood. Anti-meningococcus IgG and IgM were quantified by ELISA. Anti-measles antibody responses were quantified by haemagglutinin antibody inhibition assay. Infants infected with EBV had reduced IgG and IgM antibody responses to meningococcal polysaccharides and to measles vaccine. Infection with CMV alone predicted no changes in the response to meningococcal polysaccharide. While CMV alone had no discernable effect on the antibody response to measles, the response of infants infected with both CMV and EBV was similar to that of infants infected with neither, suggesting that the effects of CMV infection countered the effects of EBV on measles antibody responses.The results of this exploratory study indicate that infection with EBV is associated with reduced antibody responses to polysaccharides and to measles vaccine, but suggest that the response to T-cell dependent antigens such as measles haemagglutinin may be restored by infection with CMV.

  20. Prevalence of human T-lymphotropic virus type I and type II antibody among blood donors in Eastern Saudi Arabia.

    Science.gov (United States)

    Ul-Hassan, Zahoor; Al-Bahrani, Ahmad T; Panhotra, Bodh R

    2004-10-01

    Human T-cell leukemia/lymphoma virus type I and type II (HTLV-I/II) infections can be transfusion associated, leading to tropical paraparesis, myelopathy and other neurological disorders. The aim of this study is to circumvent the risk of transmission through blood transfusion and to describe the prevalence of HTLV-I/II antibody among blood donors of Al-Hasa region and the cost effectiveness of screening blood donors. The study was conducted at the Department of Laboratory and Blood Bank, King Fahad Hospital, Al-Hofuf, Al-Hasa, Kingdom of Saudi Arabia during the period of 1997 to 2003. A total of 47426 blood donors were screened for HTLV-I/II antibody by enzyme-linked immunosorbent assay test, during the 7 years of study period. The positive samples were confirmed by western blot analysis. Overall, HTLV-I antibody positivity (confirmed by western blot) was 3/47426 (0.006%). Out of 3 donors positive for HTLV-I antibody during 1997 to 1998, 2 were expatriates (Indian) and one was native Saudi donor. Human T-cell leukemia/lymphoma virus type I antibody positivity among the native Saudi donors was 1/47426 (0.002%) (2/100000 blood donors). None of the donor were positive for HTLV-II antibody. During the last 5 consecutive years of the study period (1999-2003), none of the donor was positive for HTLV-I/II antibody. Al-Hasa region is non-endemic for HTLV-I/II virus infections. Screening of native Saudi blood donors for these viruses does not appear to be cost effective.

  1. Quantitative serology assays for determination of antibody responses to Ebola virus glycoprotein and matrix protein in nonhuman primates and humans.

    Science.gov (United States)

    Vu, Hong; Shulenin, Sergey; Grolla, Allen; Audet, Jonathan; He, Shihua; Kobinger, Gary; Unfer, Robert C; Warfield, Kelly L; Aman, M Javad; Holtsberg, Frederick W

    2016-02-01

    The West Africa Ebola virus disease (EVD) outbreak has reached unprecedented magnitude and caused worldwide concerns for the spread of this deadly virus. Recent findings in nonhuman primates (NHPs) demonstrate that antibodies can be protective against EVD. However, the role of antibody response in vaccine-mediated protection is not fully understood. To address these questions quantitative serology assays are needed for measurement of the antibody response to key Ebola virus (EBOV) proteins. Serology enzyme-linked immunosorbent assays (ELISA's), using a reference detection antibody, were developed in order to standardize the quantitation of antibody levels in vaccinated NHPs or in humans exposed to EBOV or immunized with an EBOV vaccine. Critical reagents were generated to support the development of the serology ELISAs. Recombinant EBOV matrix protein (VP40) was expressed in Escherichia coli and purified. Two variants of the glycoprotein (GP), the ectodomain lacking the transmembrane domain (GPΔTM), and an engineered GP lacking the mucin-like domain (GPΔmuc) were expressed and purified from mammalian cell systems. Using these proteins, three ELISA methods were developed and optimized for reproducibility and robustness, including stability testing of critical reagents. The assay was used to determine the antibody response against VP40, GPΔTM, and GPΔmuc in a NHP vaccine study using EBOV virus-like particles (VLP) vaccine expressing GP, VP40 and the nucleoprotein. Additionally, these ELISAs were used to successfully detect antibody responses to VP40, GPΔTM and GPΔmuc in human sera from EBOV infected individuals. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Seroprevalence of fecal-oral transmitted hepatitis A and E virus antibodies in Burkina Faso.

    Science.gov (United States)

    Traoré, Kuan Abdoulaye; Rouamba, Hortense; Nébié, Yacouba; Sanou, Mahamadou; Traoré, Alfred S; Barro, Nicolas; Roques, Pierre

    2012-01-01

    Hepatitis A virus (HAV) and hepatitis E virus (HEV) infections occur chiefly as a result of unhygienic conditions. The purpose of this study was to assess the seroprevalence of antibodies to both viruses in central Burkina Faso in the absence of a recorded hepatitis epidemic. Serum samples from 178 blood donors (131 males and 47 females) and from 189 pregnant women were collected from November 2010 to March 2012, at blood banks and medical centers in Burkina Faso. An immunochromatography test was used to screen for Anti-HAV IgM and IgG in a subgroup of 91 blood donors and 100 pregnant women. The seroprevalence of anti-HAV IgG was 14.3% [CI95, 7.1-21.4%] for all blood donors and 23% [CI95, 14.8-31.2%] for pregnant women. Anti-HEV IgG were detected using the ELISA kits Dia.pro and Wantai and were found in 19.1% [CI95, 13.3-24.9%] of the blood donors and 11.6% [CI95, 7.1-16.2%] of the pregnant women. The seroprevalences of anti-HAV and anti-HEV IgGs did not differ significantly between men and women blood donors. Anti-HAV IgM was detected in 3.3% of the blood donors and in 2% of the pregnant women. These findings for asymptomatic individuals indicate that the HAV and HEV circulate at low but significant levels. This is the first evaluation of the acute hepatitis virus burden in Burkina Faso and the underlying epidemiologic status of the population.

  3. Defining New Therapeutics Using a More Immunocompetent Mouse Model of Antibody-Enhanced Dengue Virus Infection.

    Science.gov (United States)

    Pinto, Amelia K; Brien, James D; Lam, Chia-Ying Kao; Johnson, Syd; Chiang, Cindy; Hiscott, John; Sarathy, Vanessa V; Barrett, Alan D; Shresta, Sujan; Diamond, Michael S

    2015-09-15

    With over 3.5 billion people at risk and approximately 390 million human infections per year, dengue virus (DENV) disease strains health care resources worldwide. Previously, we and others established models for DENV pathogenesis in mice that completely lack subunits of the receptors (Ifnar and Ifngr) for type I and type II interferon (IFN) signaling; however, the utility of these models is limited by the pleotropic effect of these cytokines on innate and adaptive immune system development and function. Here, we demonstrate that the specific deletion of Ifnar expression on subsets of murine myeloid cells (LysM Cre(+) Ifnar(flox/flox) [denoted as Ifnar(f/f) herein]) resulted in enhanced DENV replication in vivo. The administration of subneutralizing amounts of cross-reactive anti-DENV monoclonal antibodies to LysM Cre(+) Ifnar(f/f) mice prior to infection with DENV serotype 2 or 3 resulted in antibody-dependent enhancement (ADE) of infection with many of the characteristics associated with severe DENV disease in humans, including plasma leakage, hypercytokinemia, liver injury, hemoconcentration, and thrombocytopenia. Notably, the pathogenesis of severe DENV-2 or DENV-3 infection in LysM Cre(+) Ifnar(f/f) mice was blocked by pre- or postexposure administration of a bispecific dual-affinity retargeting molecule (DART) or an optimized RIG-I receptor agonist that stimulates innate immune responses. Our findings establish a more immunocompetent animal model of ADE of infection with multiple DENV serotypes in which disease is inhibited by treatment with broad-spectrum antibody derivatives or innate immune stimulatory agents. Although dengue virus (DENV) infects hundreds of millions of people annually and results in morbidity and mortality on a global scale, there are no approved antiviral treatments or vaccines. Part of the difficulty in evaluating therapeutic candidates is the lack of small animal models that are permissive to DENV and recapitulate the clinical features

  4. Molecular determinants of dengue virus 2 envelope protein important for virus entry in FcγRIIA-mediated antibody-dependent enhancement of infection

    International Nuclear Information System (INIS)

    Chotiwan, Nunya; Roehrig, John T.; Schlesinger, Jacob J.; Blair, Carol D.; Huang, Claire Y.-H.

    2014-01-01

    Antibody-dependent enhancement (ADE) of infection may cause severe illness in patients suffering a secondary infection by a heterologous dengue virus (DENV) serotype. During ADE of infection, cross-reactive non- or poorly-neutralizing antibodies form infectious virus-Ab complexes with the newly infecting serotype and enhance virus infection by binding to the Fcγ receptors (FcγR) on FcγR-bearing cells. In this study, we determined that molecular determinants of DENV2 envelope protein critical for virus entry during non-ADE infection are also required for ADE infection mediated by FcγRIIA, and binding of virus-Ab complexes with FcγRIIA alone is not sufficient for ADE of infection. The FcγRIIA mainly plays an auxiliary role in concentrating the virus–Ab complex to the cell surface, and other primary cellular receptors are required for virus entry. Understanding the viral entry pathway in ADE of DENV infection will greatly facilitate rational designs of anti-viral therapeutics against severe dengue disease associated with ADE. - Highlights: • KKK305/307/310 in DENV2 E-DIII is critical for virus attachment in ADE and non-ADE infection. • Binding of DENV2–Ab complex with FcγRII alone is not sufficient for virus entry in ADE infection. • Other primary receptors were required for DENV2 internalization during FcγRII–mediated ADE. • G104 and L135 of DENV2 E are critical for virus-mediated membrane fusion. • DENV2 virus-mediated membrane fusion is required for both ADE and non-ADE infection

  5. Molecular determinants of dengue virus 2 envelope protein important for virus entry in FcγRIIA-mediated antibody-dependent enhancement of infection

    Energy Technology Data Exchange (ETDEWEB)

    Chotiwan, Nunya; Roehrig, John T. [Arboviral Diseases Branch, Division of Vector-Borne Disease, Centers for Disease Control and Prevention, Fort Collins, CO 80521 (United States); Schlesinger, Jacob J. [Department of Medicine, University of Rochester, Rochester, NY 14642 (United States); Blair, Carol D. [Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523 (United States); Huang, Claire Y.-H., E-mail: yxh0@cdc.gov [Arboviral Diseases Branch, Division of Vector-Borne Disease, Centers for Disease Control and Prevention, Fort Collins, CO 80521 (United States)

    2014-05-15

    Antibody-dependent enhancement (ADE) of infection may cause severe illness in patients suffering a secondary infection by a heterologous dengue virus (DENV) serotype. During ADE of infection, cross-reactive non- or poorly-neutralizing antibodies form infectious virus-Ab complexes with the newly infecting serotype and enhance virus infection by binding to the Fcγ receptors (FcγR) on FcγR-bearing cells. In this study, we determined that molecular determinants of DENV2 envelope protein critical for virus entry during non-ADE infection are also required for ADE infection mediated by FcγRIIA, and binding of virus-Ab complexes with FcγRIIA alone is not sufficient for ADE of infection. The FcγRIIA mainly plays an auxiliary role in concentrating the virus–Ab complex to the cell surface, and other primary cellular receptors are required for virus entry. Understanding the viral entry pathway in ADE of DENV infection will greatly facilitate rational designs of anti-viral therapeutics against severe dengue disease associated with ADE. - Highlights: • KKK305/307/310 in DENV2 E-DIII is critical for virus attachment in ADE and non-ADE infection. • Binding of DENV2–Ab complex with FcγRII alone is not sufficient for virus entry in ADE infection. • Other primary receptors were required for DENV2 internalization during FcγRII–mediated ADE. • G104 and L135 of DENV2 E are critical for virus-mediated membrane fusion. • DENV2 virus-mediated membrane fusion is required for both ADE and non-ADE infection.

  6. Virus neutralizing antibody response in mice and dogs with a bicistronic DNA vaccine encoding rabies virus glycoprotein and canine parvovirus VP2.

    Science.gov (United States)

    Patial, Sonika; Chaturvedi, V K; Rai, A; Saini, M; Chandra, Rajesh; Saini, Y; Gupta, Praveen K

    2007-05-16

    A bicistronic DNA vaccine against rabies and parvovirus infection of dogs was developed by subcloning rabies glycoprotein and canine parvovirus (CPV) VP2 genes into a bicistronic vector. After characterizing the expression of both the proteins in vitro, the bicistronic DNA vaccine was injected in mice and induced immune response was compared with monocistronic DNA vaccines. There was no significant difference in ELISA and virus neutralizing (VN) antibody responses against rabies and CPV in mice immunized with either bicistronic or monocistronic DNA vaccine. Further, there was significantly similar protection in mice immunized with either bicistronic or monocistronic rabies DNA vaccine on rabies virus challenge. Similarly, dogs immunized with monocistronic and bicistronic DNA vaccines developed comparable VN antibodies against rabies and CPV. This study indicated that bicistronic DNA vaccine can be used in dogs to induce virus neutralizing immune responses against both rabies and CPV.

  7. Establishment of the cross-clade antigen detection system for H5 subtype influenza viruses using peptide monoclonal antibodies specific for influenza virus H5 hemagglutinin.

    Science.gov (United States)

    Takahashi, Hitoshi; Nagata, Shiho; Odagiri, Takato; Kageyama, Tsutomu

    2018-04-15

    The H5 subtype of highly pathogenic avian influenza (H5 HPAI) viruses is a threat to both animal and human public health and has the potential to cause a serious future pandemic in humans. Thus, specific and rapid detection of H5 HPAI viruses is required for infection control in humans. To develop a simple and rapid diagnostic system to detect H5 HPAI viruses with high specificity and sensitivity, we attempted to prepare monoclonal antibodies (mAbs) that specifically recognize linear epitopes in hemagglutinin (HA) of H5 subtype viruses. Nine mAb clones were obtained from mice immunized with a synthetic partial peptide of H5 HA molecules conserved among various H5 HPAI viruses. The antigen-capture enzyme-linked immunosorbent assay using the most suitable combination of these mAbs, which bound specifically to lysed H5 HA under an optimized detergent condition, was specific for H5 viruses and could broadly detect H5 viruses in multiple different clades. Taken together, these peptide mAbs, which recognize linear epitopes in a highly conserved region of H5 HA, may be useful for specific and highly sensitive detection of H5 HPAI viruses and can help in the rapid diagnosis of human, avian, and animal H5 virus infections. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. Simple and efficient generation of virus-specific T cells for adoptive therapy using anti-4-1BB antibody.

    Science.gov (United States)

    Imahashi, Nobuhiko; Nishida, Tetsuya; Goto, Tatsunori; Terakura, Seitaro; Watanabe, Keisuke; Hanajiri, Ryo; Sakemura, Reona; Imai, Misa; Kiyoi, Hitoshi; Naoe, Tomoki; Murata, Makoto

    2015-01-01

    Although recent studies of virus-specific T-cell (VST) therapy for viral infections after allogeneic hematopoietic stem cell transplantation have shown promising results, simple and less time-intensive and labor-intensive methods are required to generate VSTs for the wider application of VST therapy. We investigated the efficacy of anti-CD28 and anti-4-1BB antibodies, which can provide T cells with costimulatory signals similar in strength to those of antigen-presenting cells, in generating VSTs. When peripheral blood mononuclear cells were stimulated with viral peptides together with isotype control, anti-CD28, or anti-4-1BB antibodies, anti-4-1BB antibodies yielded the highest numbers of VSTs, which were on an average 7.9 times higher than those generated with isotype control antibody. The combination of anti-CD28 and anti-4-1BB antibodies did not result in increased numbers of VSTs compared with anti-4-1BB antibody alone. Importantly, the positive effect of anti-4-1BB antibody was observed regardless of the epitopes of the VSTs. In contrast, the capacity of dendritic cells (DCs) to generate VSTs differed considerably depending on the epitopes of the VSTs. Furthermore, the numbers of VSTs generated with DCs were at most similar to those generated with the anti-4-1BB antibody. Generation of VSTs with anti-4-1BB antibody did not result in excessive differentiation or deteriorated function of the generated VSTs compared with those generated with control antibody or DCs. In conclusion, VSTs can be generated rapidly and efficiently by simply stimulating peripheral blood mononuclear cells with viral peptide and anti-4-1BB antibody without using antigen-presenting cells. We propose using anti-4-1BB antibody as a novel strategy to generate VSTs for adoptive therapy.

  9. H7N9 Avian Influenza Virus Is Efficiently Transmissible and Induces an Antibody Response in Chickens

    Directory of Open Access Journals (Sweden)

    Peirong Jiao

    2018-04-01

    Full Text Available H7N9 viruses pose a threat to human health and they are no less harmful to the poultry industry than the H5N1 avian influenza viruses. However, the pathogenesis, transmissibility, and the host immune response of the H7N9 virus in chickens and mice remain unclear. In this study, we found that H7N9 viruses replicated in multiple organs of the chicken and viral shedding persisted up to 30 days postinoculation (DPI. The viruses were efficiently transmitted between chickens through direct contact. Notably, chickens infected with H7N9 had high antibody levels throughout the entire observation period and their antibody response lasted for 30 DPI. The expression levels of the pattern-recognition receptors and pro-inflammatory cytokines were found to be significantly upregulated in the brain using quantitative real-time PCR. The expression of TLR3, TLR7, MDA5, Mx, IL-1β, IL-6, IFN-α, and IFN-γ were also significantly different in the lungs of infected chickens. We found that the viruses isolated from these birds had low pathogenicity in mice, produced little weight loss and could only replicate in the lungs. Our findings suggested that the H7N9 viruses could replicate in chickens and mice and be efficiently transmitted between chickens, which presented a significant threat to human and poultry health.

  10. Evaluation of bovine coronavirus antibody levels, virus shedding, and respiratory disease incidence throughout the beef cattle production cycle

    Science.gov (United States)

    Objective- Determine how levels of serum antibody to bovine coronavirus (BCV) are related to virus shedding patterns and respiratory disease incidence in beef calves at various production stages. Animals- 890 crossbred beef calves from four separately managed herds at the U.S. Meat Animal Research C...

  11. The molecular determinants of antibody recognition and antigenic drift in the H3 hemagglutinin of swine influenza A virus

    Science.gov (United States)

    Influenza A virus (IAV) of the H3 subtype is an important pathogen that affects both humans and swine. The main intervention strategy for preventing infection is vaccination to induce neutralizing antibodies against the surface glycoprotein hemagglutinin (HA). However, due to antigenic drift, vaccin...

  12. Ebola virus-like particles produced in insect cells exhibit dendritic cell stimulating activity and induce neutralizing antibodies

    International Nuclear Information System (INIS)

    Ye Ling; Lin Jianguo; Sun Yuliang; Bennouna, Soumaya; Lo, Michael; Wu Qingyang; Bu Zhigao; Pulendran, Bali; Compans, Richard W.; Yang Chinglai

    2006-01-01

    Recombinant baculoviruses (rBV) expressing Ebola virus VP40 (rBV-VP40) or GP (rBV-GP) proteins were generated. Infection of Sf9 insect cells by rBV-VP40 led to assembly and budding of filamentous particles from the cell surface as shown by electron microscopy. Ebola virus-like particles (VLPs) were produced by coinfection of Sf9 cells with rBV-VP40 and rBV-GP, and incorporation of Ebola GP into VLPs was demonstrated by SDS-PAGE and Western blot analysis. Recombinant baculovirus infection of insect cells yielded high levels of VLPs, which were shown to stimulate cytokine secretion from human dendritic cells similar to VLPs produced in mammalian cells. The immunogenicity of Ebola VLPs produced in insect cells was evaluated by immunization of mice. Analysis of antibody responses showed that most of the GP-specific antibodies were of the IgG2a subtype, while no significant level of IgG1 subtype antibodies specific for GP was induced, indicating the induction of a Th1-biased immune response. Furthermore, sera from Ebola VLP immunized mice were able to block infection by Ebola GP pseudotyped HIV virus in a single round infection assay, indicating that a neutralizing antibody against the Ebola GP protein was induced. These results show that production of Ebola VLPs in insect cells using recombinant baculoviruses represents a promising approach for vaccine development against Ebola virus infection

  13. Analysis of antigenic relationships among influenza virus strains using a taxonomic cluster procedure. Comparison of three kinds of antibody preparations.

    NARCIS (Netherlands)

    T.F. Weijers; A.D.M.E. Osterhaus (Albert); W.E.Ph. Beyer (Walter); J.A.A.M. van Asten (Jack); F.M. de Ronde-Verloop; K. Bijlsma (Klaas); J.C. de Jong (Jan)

    1985-01-01

    textabstractHemagglutination inhibiting (HI) monoclonal antibody preparations (MA) were raised against six influenza A (H3N2) strains from the period 1977-1982. Twenty-three hybridomas were selected and titrated in HI assays against these strains and against 18 influenza A (H3N2) viruses isolated in

  14. Structure of the extracellular domain of matrix protein 2 of influenza A virus in complex with a protective monoclonal antibody.

    Science.gov (United States)

    Cho, Ki Joon; Schepens, Bert; Seok, Jong Hyeon; Kim, Sella; Roose, Kenny; Lee, Ji-Hye; Gallardo, Rodrigo; Van Hamme, Evelien; Schymkowitz, Joost; Rousseau, Frederic; Fiers, Walter; Saelens, Xavier; Kim, Kyung Hyun

    2015-04-01

    The extracellular domain of influenza A virus matrix protein 2 (M2e) is conserved and is being evaluated as a quasiuniversal influenza A vaccine candidate. We describe the crystal structure at 1.6 Å resolution of M2e in complex with the Fab fragment of an M2e-specific monoclonal antibody that protects against influenza A virus challenge. This antibody binds M2 expressed on the surfaces of cells infected with influenza A virus. Five out of six complementary determining regions interact with M2e, and three highly conserved M2e residues are critical for this interaction. In this complex, M2e adopts a compact U-shaped conformation stabilized in the center by the highly conserved tryptophan residue in M2e. This is the first description of the three-dimensional structure of M2e. M2e of influenza A is under investigation as a universal influenza A vaccine, but its three-dimensional structure is unknown. We describe the structure of M2e stabilized with an M2e-specific monoclonal antibody that recognizes natural M2. We found that the conserved tryptophan is positioned in the center of the U-shaped structure of M2e and stabilizes its conformation. The structure also explains why previously reported in vivo escape viruses, selected with a similar monoclonal antibody, carried proline residue substitutions at position 10 in M2. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  15. In vivo evaluation of the cross-genotype neutralizing activity of polyclonal antibodies against hepatitis C virus

    DEFF Research Database (Denmark)

    Meuleman, Philip; Bukh, Jens; Verhoye, Lieven

    2011-01-01

    Control of hepatitis C virus (HCV) infection remains a huge challenge of global medical importance. Using a variety of in vitro approaches, neutralizing antibodies (nAbs) have been identified in patients with acute and chronic hepatitis C. The exact role these nAbs play in the resolution of acute...

  16. In vivo neutralization of hepatitis B virus infection by an anti-preS1 humanized antibody in chimpanzees

    International Nuclear Information System (INIS)

    Hong, Hyo Jeong; Ryu, Chun Jeih; Hur, Hyangsuk; Kim, Seho; Oh, Han Kyu; Oh, Mee Sook; Park, Song Yong

    2004-01-01

    Previously, we generated a murine monoclonal antibody (mAb), KR127, that recognizes amino acids (aa) 37-45 of the preS1 of hepatitis B virus (HBV). In this study, we have constructed a humanized version of KR127 and evaluated its HBV-neutralizing activity in chimpanzees. A study chimpanzee was given a single intravenous dose of the humanized antibody, followed by intravenous challenge with adr subtype of wild type HBV, while a control chimpanzee was only challenged with the virus. The result showed that the study chimpanzee did not develop HBV infection during 1 year, while the control chimpanzee was infected, indicating that the humanized antibody exhibited in vivo virus-neutralizing activity and thus protected the chimpanzee from HBV infection. In addition, the humanized antibody bound to the preS1 of all subtypes of HBV. We first demonstrate that an anti-preS1 mAb can neutralize HBV infection in vivo. This humanized antibody will be useful for the immunoprophylaxis of HBV infection

  17. Preclinical evaluation of VIS513, a therapeutic antibody against dengue virus, in non-human primates.

    Science.gov (United States)

    Ong, Eugenia Z; Budigi, Yadunanda; Tan, Hwee Cheng; Robinson, Luke N; Rowley, Kirk J; Winnett, Alexander; Hobbie, Sven; Shriver, Zachary; Babcock, Gregory J; Ooi, Eng Eong

    2017-08-01

    Despite useful in vivo activity, no therapeutic against dengue virus (DENV) has demonstrated efficacy in clinical trials. Herein, we explored dosing and virological endpoints to guide the design of human trials of VIS513, a pan-serotype anti-DENV IgG1 antibody, in non-human primates (NHPs). Dosing VIS513 pre- or post-peak viremia in NHPs neutralized infectious DENV although RNAemia remained detectable post-treatment; differential interaction of human IgGs with macaque Fc-gamma receptors may delay clearance of neutralized DENV. Our findings suggest useful antiviral utility of VIS513 and highlight an important consideration when evaluating virological endpoints of trials for anti-DENV biologics. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Detection of Antibody to Envelope (E2 Antigen of Hepatitis C Virus

    Directory of Open Access Journals (Sweden)

    RK Chaudhary

    1997-01-01

    Full Text Available One hundred and four clinical specimens from provincial public health laboratories were tested for antibody to hepatitis C virus (HCV envelope protein (anti-E2. To evaluate the effect of hypervariability of E2 region on anti-E2 assay, 49 recombinant immunoblot assay (RIBA 3.0 positive samples were genotyped. All 49 genotyped samples were positive for anti-E2. Eight of 12 (67% indeterminate, HCV RNA positive samples were anti-E2 reactive. Nine of 30 (30% indeterminate, HCV RNA negative samples were also positive for anti-E2. Anti-E2 was detected in two of 13 (15% RIBA-negative and enzyme immunoassays-positive samples. Although small number of samples were tested, the results showed that it may be possible to resolve indeterminate samples with the anti-E2 assay.

  19. Experiments toward the development of a radioimmunoassay for the detection of serum antibodies for the respiratory syncytial virus

    International Nuclear Information System (INIS)

    Heizmann, W.R.

    1982-01-01

    In order to detect an infection by the respiratory syncytial virus (RSV) quickly and safely, a radioimmunassay (RIA) should be developed. Various antigen preparations were compared to one another. The immune serums used in the RIA came from guinea pigs with a RSV antibody titer of up to 320 in the complement binding reaction. A number of observations lead to the discussion of the possibility of the formation (incomplete) of cross-reactive antibodies between virus and host cell. This hypothesis could be well supported through references in the literature. Under the assumption of the existence of cross-reactive antibodies, a further model of the pathogenesis of the RSV illness allows itself to be developed, which could be preceived as an illness with autoimmune components. With this model the varying courses of this disease in different age groups can be easily explained. (orig.) [de

  20. Role of neutralizing antibodies and T-cells in pathogenesis of herpes simplex virus infection in congenitally athymic mice.

    Science.gov (United States)

    Kapoor, A K; Buckmaster, A; Nash, A A; Field, H J; Wildy, P

    1982-11-01

    Congenitally athymic nude mice were infected with 10(4) p.f.u. herpes simplex type 1 (strain SC16). Following the passive transfer of neutralizing monoclonal antibodies (AP7, AP8 and AP12) it was observed that AP7 alone reduced the virus infectivity in the nervous system; AP8 and AP12 failed to protect mice probably due to poor in vivo binding to the neutralization site on the virus. Latent ganglionic infection could be established in nude mice following adoptive transfer of optimum number (2 x 10(7) cells/mouse) of immune lymph node cells from day 7 herpes virus-infected hairy immunocompetent donor mice. Moreover, in some of the immune lymph node cell protected nudes, latency could be maintained even in complete absence of neutralizing antibodies. Results of ear-ablation experiments revealed that removal of primary source of infection after day 5 of infection reduced the amount of virus in the ganglia and spinal cord. Acute neurological infection was not detected following transfer of protective anti-gp-D neutralizing antibody (LP2) in combination with removal of infected pinna. These data suggest that continuous seeding of virus occurs in related ganglia via the axonal route from infected ear pinna. It appears that local T-cell-mediated immune mechanisms are involved in maintenance of latency.

  1. Coccidian and nematode infections influence prevalence of antibody to myxoma and rabbit hemorrhagic disease viruses in European rabbits.

    Science.gov (United States)

    Bertó-Moran, Alejandro; Pacios, Isabel; Serrano, Emmanuel; Moreno, Sacramento; Rouco, Carlos

    2013-01-01

    The interaction among several parasites in European rabbits (Oryctolagus cuniculus) is crucial to host fitness and to the epidemiology of myxomatosis and rabbit hemorrhagic disease. These diseases have caused significant reductions in rabbit populations on the Iberian Peninsula. Most studies have focused on the epidemiology and pathogenesis of these viruses individually, and little is known about interactions between these viruses and other parasites. Taking advantage of an experimental restocking program in Spain, the effects of coccidian and nematode infections on the probability of having detectable antibody to myxoma and rabbit hemorrhagic disease viruses were tested in European wild rabbits. For 14 mo, we monitored rabbit abundance and parasite loads (coccidia and nematodes) in three reintroduced rabbit populations. While coccidian and nematode loads explained seasonal antibody prevalences to myxoma virus, the pattern was less clear for rabbit hemorrhagic disease. Contrary to expectations, prevalence of antibody to myxoma virus was inversely proportional to coccidian load, while nematode load seemed to play a minor role. These results have implications for viral disease epidemiology and for disease management intended to increase rabbit populations in areas where they are important for ecosystem conservation.

  2. HEMORRHAGIC-FEVER VIRUS-INFECTIONS IN AN ISOLATED RAIN-FOREST AREA OF CENTRAL LIBERIA - LIMITATIONS OF THE INDIRECT IMMUNOFLUORESCENCE SLIDE TEST FOR ANTIBODY SCREENING IN AFRICA

    NARCIS (Netherlands)

    van der Waals, F. W.; Pomeroy, K. L.; Goudsmit, J.; Asher, D. M.; Gajdusek, D. C.

    1986-01-01

    Serum samples from 119 healthy individuals and 106 epilepsy patients inhabiting Grand Bassa County, Liberia, were tested for antibodies to hemorrhagic fever viruses (HFV) by indirect immunofluorescence. E6 Vero cells infected with Lassa fever virus (LAS), Rift Valley Fever virus (RVF), Congo

  3. Monoclonal antibody-based serological methods for detection of Cucumber green mottle mosaic virus

    Directory of Open Access Journals (Sweden)

    Qian Yajuan

    2011-05-01

    Full Text Available Abstract Background Cucumber green mottle mosaic virus (CGMMV, a member of the genus Tobamovirus, can be transmitted by seeds and infects many cucurbit species, causing serious yield losses in cucumber and watermelon plants. In this paper, five serological methods including antigen-coated plate enzyme-linked immunosorbent assay (ACP-ELISA, triple antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA, Dot-immunobinding assay (DBIA, direct tissue blot immunoassay (DTBIA and immunocapture reverse transcriptase polymerase chain reaction (IC-RT-PCR were described for detection and diagnosis of CGMMV. Results Using the purified CGMMV particles as immunogens, six murine monoclonal antibodies (MAbs were produced. Five serological methods were established using the MAb 4H1 and detection sensitivity was compared using purified preparations and infected-plant tissue extracts. The detection sensitivity of ACP-ELISA was 0.16 ng of purified CGMMV, whereas TAS-ELISA was more sensitive than ACP-ELISA with a minimum detection of 0.04 ng of purified CGMMV. The sensitivities of TAS-ELISA and DBIA were similar for detecting CGMMV in infected-plant tissue extracts, and were four times higher than ACP-ELISA. The IC-RT-PCR was the most sensitive method, which could detect as little as 0.1 pg of purified virus. The detection sensitivity of IC-RT-PCR for CGMMV-infected plant tissues was about 400 times higher than that of TAS-ELISA and DBIA. Conclusions The established ACP-ELISA, TAS-ELISA, DBIA and DTBIA are suitable for routine CGMMV detection of large-scale samples in the field survey, while IC-RT-PCR is more sensitive and suitable for acquiring information about the viral genome.

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

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    Gene S Tan

    2016-04-01

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

  5. [Establishment of chemiluminescent enzyme immunoassay for detecting antibodies against foot-and-mouth disease virus serotype O in swine].

    Science.gov (United States)

    Cui, Chen; Huang, Ligang; Li, Jing; Zou, Xingqi; Zhu, Yuanyuan; Xie, Lei; Zhao, Qizu; Yang, Limin; Liu, Wenjun

    2016-11-25

    Recombinant structural protein VP1 of foot-and-mouth disease virus serotype O was expressed in Escherichia coli and then purified using Nickel affinity chromatography. A chemiluminescent enzyme immunoassay (CLEIA) method was established using the purified recombinant protein as coating antigen to detect antibody of foot-and-mouth disease virus serotype O in swine. The specificity of VP1-CLEIA method is 100%. The coefficients of variation in the plate and between plates are 1.10%-6.70% and 0.66%-4.80%, respectively. Comparing with the commercial indirect ELISA kit or liquid phase block ELISA kit, the calculated coincidence rate is 93.50% or 94.00%. The high specificity and stability suggested this detection method can be used to monitor the antibody level of foot-and-mouth disease virus serotype O in swine.

  6. Construction and Characterization of a Humanized Anti-Epstein-Barr Virus gp350 Antibody with Neutralizing Activity in Cell Culture

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    Jerome E. Tanner

    2018-04-01

    Full Text Available Acute Epstein-Barr virus (EBV infection in immunosuppressed transplant patients can give rise to a malignant B-cell proliferation known as post-transplant lymphoproliferative disease (PTLD. The EBV major virion surface glycoprotein (gp350 is a principal target of naturally occurring neutralizing antibodies and is viewed as the best target to prevent acute infection and PTLD in at-risk transplant recipients. We have constructed a humanized (hu version of the murine anti-gp350 neutralizing monoclonal antibody 72a1. The hu72a1 IgG1 antibody displayed no significant anti-mouse activity, recognized both gp350 and its splice variant gp220 as well as a gp350 peptide that was shown to constitute the principal EBV gp350 neutralizing epitope when tested in immunoassays. Hu72a1 antibody blocked in vitro EBV infection of B cells at a level which equaled that of a mouse-human chimeric 72a1 antibody construct. This work provides a further structural and immunological understanding of the 72a1 antibody interaction with EBV gp350, and constitutes a launch point for future anti-EBV therapeutic antibodies designed to block EBV infection and prevent PTLD while eliminating the deleterious antigenic murine features of the original 72a1 antibody.

  7. A ''reverse'' solid-phase radio-immuno-assay for IgM-antibodies to hepatitis A virus

    International Nuclear Information System (INIS)

    Meurman, O.H.; Matter, L.; Krishna, R.V.; Krech, U.H.

    1981-01-01

    A ''reverse'' solid-phase radio-immuno-assay for IgM antibodies to hepatitis A virus (HAV) was developed. Anti-human IgM immunoglobulins were bound on the wells of polyvinylchloride microtiter plates. Serum specimens were incubated in the anti-human IgM coated wells and bound IgM antibodies were then assayed for antigen specificity by subsequent incubations with HAV antigen and 125 I-labelled human anti-HAV IgG. The test showed a high sensitivity and specificity for anti-HAV IgM antibodies. No false-positive reactions were observed either in the sera from patients with hepatobiliary disorders other than HAV infection or in the sera containing both rheumatoid factor and anti-HAV IgG antibodies. In acute HAV infections specific IgM antibodies were present already in the first specimens taken within a few days after the onset of jaundice. The persistence of the IgM antibodies was from 4 to 6 months. IgM antibody titers up to 1,000,000 were observed in the acute phase of HAV infection. In routine diagnostic work the titration of the sera was not necessary, since a reliable qualitative result was obtained by testing the sera in a single dilution of 1:100. A similar ''reverse'' immuno-assay principle may be adaptable for the diagnostic determination of IgM antibodies to different viral and microbial antigens. (author)

  8. Effects of long-term low dose radiation. Epstein-Barr virus-specific antibodies in radiological technologists

    Energy Technology Data Exchange (ETDEWEB)

    Kumagai, Etsuko; Higashida, Yoshiharu; Onomichi, Mitsukazu; Nakamura, Ikuo; Tanoue, Shozo; Tanaka, Ryuji; Kumagai, Takashi; Katsuki, Takato; Sawada, Shozo.

    1988-09-01

    To clarify the long-term effects of occupational exposure to low doses of radiation, Epstein-Barr virus (EBV)-specific antibody titers in sera from 104 radiological technologists (R.T.) and 118 controls in Kumamoto prefecture were measured by the immunofluorescence method. Antibody titers to viral capsid antigen (VCA)-IgG increased with the years of experience as R.T., and the prevalence of abnormal antibody titers to both VCA-IgG and early antigen (EA)-IgG were significantly higher in R.T. with over 15 years of experience or 30 rads of cumulative radiation dose than in the controls. However, there was no correlation between exposure and the frequency of abnormal EBV-associated nuclear antigen (EBNA) antibody titers. The EBV-specific antibody titers of 24 Hiroshima atomic-bomb survivors were also measured. They were similar to those of the R.T. with over 30 years of experience. The EBV-specific antibody titers of R.T. suggest that there may be an impairment of immunologic competence after continuous long-term exposure to low doses of radiation. Also, the correlation of EBV-specific antibody titers and frequency of cells with chromosome aberrations in 53 R.T. was studied. Some correlations were found between the antibody titers to both of the VCA-IgG and EBNA and the frequency of cells with chromosome aberrations.

  9. A Diverse Panel of Hepatitis C Virus Glycoproteins for Use in Vaccine Research Reveals Extremes of Monoclonal Antibody Neutralization Resistance.

    Science.gov (United States)

    Urbanowicz, Richard A; McClure, C Patrick; Brown, Richard J P; Tsoleridis, Theocharis; Persson, Mats A A; Krey, Thomas; Irving, William L; Ball, Jonathan K; Tarr, Alexander W

    2015-12-23

    Despite significant advances in the treatment of hepatitis C virus (HCV) infection, the need to develop preventative vaccines remains. Identification of the best vaccine candidates and evaluation of their performance in preclinical and clinical development will require appropriate neutralization assays utilizing diverse HCV isolates. We aimed to generate and characterize a panel of HCV E1E2 glycoproteins suitable for subsequent use in vaccine and therapeutic antibody testing. Full-length E1E2 clones were PCR amplified from patient-derived serum samples, cloned into an expression vector, and used to generate viral pseudoparticles (HCVpp). In addition, some of these clones were used to generate cell culture infectious (HCVcc) clones. The infectivity and neutralization sensitivity of these viruses were then determined. Bioinformatic and HCVpp infectivity screening of approximately 900 E1E2 clones resulted in the assembly of a panel of 78 functional E1E2 proteins representing distinct HCV genotypes and different stages of infection. These HCV glycoproteins differed markedly in their sensitivity to neutralizing antibodies. We used this panel to predict antibody efficacy against circulating HCV strains, highlighting the likely reason why some monoclonal antibodies failed in previous clinical trials. This study provides the first objective categorization of cross-genotype patient-derived HCV E1E2 clones according to their sensitivity to antibody neutralization. It has shown that HCV isolates have clearly distinguishable neutralization-sensitive, -resistant, or -intermediate phenotypes, which are independent of genotype. The panel provides a systematic means for characterization of the neutralizing response elicited by candidate vaccines and for defining the therapeutic potential of monoclonal antibodies. Hepatitis C virus (HCV) has a global burden of more than 170 million people, many of whom cannot attain the new, expensive, direct-acting antiviral therapies. A safe and

  10. The nonstructural protein NSs induces a variable antibody response in domestic ruminants naturally infected with Rift Valley fever virus.

    Science.gov (United States)

    Fernandez, José-Carlos; Billecocq, Agnès; Durand, Jean Paul; Cêtre-Sossah, Catherine; Cardinale, Eric; Marianneau, Philippe; Pépin, Michel; Tordo, Noël; Bouloy, Michèle

    2012-01-01

    Rift Valley fever (RVF) is an emerging zoonosis in Africa which has spread to Egypt, the Arabian Peninsula, Madagascar, and Comoros. RVF virus (RVFV) (Bunyaviridae family, Phlebovirus genus) causes a wide range of symptoms in humans, from benign fever to fatal hemorrhagic fever. Ruminants are severely affected by the disease, which leads to a high rate of mortality in young animals and to abortions and teratogenesis in pregnant females. Diagnostic tests include virus isolation and genome or antibody detection. During RVFV infection, the nucleoprotein encapsidating the tripartite RNA genome is expressed in large amounts and raises a robust antibody response, while the envelope glycoproteins elicit neutralizing antibodies which play a major role in protection. Much less is known about the antigenicity/immunogenicity of the nonstructural protein NSs, which is a major virulence factor. Here we have developed a competitive enzyme-linked immunosorbent assay (ELISA) enabling detection of low levels of NSs-specific antibodies in naturally infected or vaccinated ruminants. Detection of the NSs antibodies was validated by Western blotting. Altogether, our data showed that the NSs antibodies were detected in only 55% of animals naturally infected by RVFV, indicating that NSs does not induce a consistently high immune response. These results are discussed in light of differentiation between infected and vaccinated animals (DIVA) tests distinguishing naturally infected animals and those vaccinated with NSs-defective vaccines.

  11. Targeting N-Glycan Cryptic Sugar Moieties for Broad-Spectrum Virus Neutralization: Progress in Identifying Conserved Molecular Targets in Viruses of Distinct Phylogenetic Origins

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    Denong Wang

    2015-03-01

    Full Text Available Identifying molecular targets for eliciting broadly virus-neutralizing antibodies is one of the key steps toward development of vaccines against emerging viral pathogens. Owing to genomic and somatic diversities among viral species, identifying protein targets for broad-spectrum virus neutralization is highly challenging even for the same virus, such as HIV-1. However, viruses rely on host glycosylation machineries to synthesize and express glycans and, thereby, may display common carbohydrate moieties. Thus, exploring glycan-binding profiles of broad-spectrum virus-neutralizing agents may provide key information to uncover the carbohydrate-based virus-neutralizing epitopes. In this study, we characterized two broadly HIV-neutralizing agents, human monoclonal antibody 2G12 and Galanthus nivalis lectin (GNA, for their viral targeting activities. Although these agents were known to be specific for oligomannosyl antigens, they differ strikingly in virus-binding activities. The former is HIV-1 specific; the latter is broadly reactive and is able to neutralize viruses of distinct phylogenetic origins, such as HIV-1, severe acute respiratory syndrome coronavirus (SARS-CoV, and human cytomegalovirus (HCMV. In carbohydrate microarray analyses, we explored the molecular basis underlying the striking differences in the spectrum of anti-virus activities of the two probes. Unlike 2G12, which is strictly specific for the high-density Man9GlcNAc2Asn (Man9-clusters, GNA recognizes a number of N-glycan cryptic sugar moieties. These include not only the known oligomannosyl antigens but also previously unrecognized tri-antennary or multi-valent GlcNAc-terminating N-glycan epitopes (Tri/m-Gn. These findings highlight the potential of N-glycan cryptic sugar moieties as conserved targets for broad-spectrum virus neutralization and suggest the GNA-model of glycan-binding warrants focused investigation.

  12. Therapeutic efficacy of antibodies lacking Fcγ receptor binding against lethal dengue virus infection is due to neutralizing potency and blocking of enhancing antibodies [corrected].

    Directory of Open Access Journals (Sweden)

    Katherine L Williams

    2013-02-01

    Full Text Available Dengue hemorrhagic fever and dengue shock syndrome (DHF/DSS are life-threatening complications following infection with one of the four serotypes of dengue virus (DENV. At present, no vaccine or antiviral therapies are available against dengue. Here, we characterized a panel of eight human or mouse-human chimeric monoclonal antibodies (MAbs and their modified variants lacking effector function and dissected the mechanism by which some protect against antibody-enhanced lethal DENV infection. We found that neutralizing modified MAbs that recognize the fusion loop or the A strand epitopes on domains II and III of the envelope protein, respectively, act therapeutically by competing with and/or displacing enhancing antibodies. By analyzing these relationships, we developed a novel in vitro suppression-of-enhancement assay that predicts the ability of modified MAbs to act therapeutically against antibody-enhanced disease in vivo. These studies provide new insight into the biology of DENV pathogenesis and the requirements for antibodies to treat lethal DENV disease.

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

    OpenAIRE

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

    2010-01-01

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

  14. Modulation of the virus-receptor interaction by mutations in the V5 loop of feline immunodeficiency virus (FIV following in vivo escape from neutralising antibody

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    Samman Ayman

    2010-04-01

    Full Text Available Abstract Background In the acute phase of infection with feline immunodeficiency virus (FIV, the virus targets activated CD4+ T cells by utilising CD134 (OX40 as a primary attachment receptor and CXCR4 as a co-receptor. The nature of the virus-receptor interaction varies between isolates; strains such as GL8 and CPGammer recognise a "complex" determinant on CD134 formed by cysteine-rich domains (CRDs 1 and 2 of the molecule while strains such as PPR and B2542 require a more "simple" determinant comprising CRD1 only for infection. These differences in receptor recognition manifest as variations in sensitivity to receptor antagonists. In this study, we ask whether the nature of the virus-receptor interaction evolves in vivo. Results Following infection with a homogeneous viral population derived from a pathogenic molecular clone, a quasispecies emerged comprising variants with distinct sensitivities to neutralising antibody and displaying evidence of conversion from a "complex" to a "simple" interaction with CD134. Escape from neutralising antibody was mediated primarily by length and sequence polymorphisms in the V5 region of Env, and these alterations in V5 modulated the virus-receptor interaction as indicated by altered sensitivities to antagonism by both anti-CD134 antibody and soluble CD134. Conclusions The FIV-receptor interaction evolves under the selective pressure of the host humoral immune response, and the V5 loop contributes to the virus-receptor interaction. Our data are consistent with a model whereby viruses with distinct biological properties are present in early versus late infection and with a shift from a "complex" to a "simple" interaction with CD134 with time post-infection.

  15. Modulation of the virus-receptor interaction by mutations in the V5 loop of feline immunodeficiency virus (FIV) following in vivo escape from neutralising antibody.

    Science.gov (United States)

    Willett, Brian J; Kraase, Martin; Logan, Nicola; McMonagle, Elizabeth L; Samman, Ayman; Hosie, Margaret J

    2010-04-26

    In the acute phase of infection with feline immunodeficiency virus (FIV), the virus targets activated CD4+ T cells by utilising CD134 (OX40) as a primary attachment receptor and CXCR4 as a co-receptor. The nature of the virus-receptor interaction varies between isolates; strains such as GL8 and CPGammer recognise a "complex" determinant on CD134 formed by cysteine-rich domains (CRDs) 1 and 2 of the molecule while strains such as PPR and B2542 require a more "simple" determinant comprising CRD1 only for infection. These differences in receptor recognition manifest as variations in sensitivity to receptor antagonists. In this study, we ask whether the nature of the virus-receptor interaction evolves in vivo. Following infection with a homogeneous viral population derived from a pathogenic molecular clone, a quasispecies emerged comprising variants with distinct sensitivities to neutralising antibody and displaying evidence of conversion from a "complex" to a "simple" interaction with CD134. Escape from neutralising antibody was mediated primarily by length and sequence polymorphisms in the V5 region of Env, and these alterations in V5 modulated the virus-receptor interaction as indicated by altered sensitivities to antagonism by both anti-CD134 antibody and soluble CD134. The FIV-receptor interaction evolves under the selective pressure of the host humoral immune response, and the V5 loop contributes to the virus-receptor interaction. Our data are consistent with a model whereby viruses with distinct biological properties are present in early versus late infection and with a shift from a "complex" to a "simple" interaction with CD134 with time post-infection.

  16. Evaluation of performance of human immunodeficiency virus antigen/antibody combination assays in Taiwan.

    Science.gov (United States)

    Chang, Chun-Kai; Kao, Cheng-Feng; Lin, Pi-Han; Huang, Hui-Lin; Ho, Shu-Yuan; Wong, Kuo-Chen; Lin, Bo-Chang; Yeh, Chang-Ching; Lee, Chia-Yeh; Kao, Chuan-Liang; Lee, Chun-Nan; Chang, Sui-Yuan; Yang, Jyh-Yuan

    2017-08-01

    The fourth-generation human immunodeficiency virus (HIV) combination assay, which can simultaneously detect the presence of anti-HIV antibody and HIV antigen, has been shown to shorten the window period in HIV diagnosis compared with the third-generation HIV antibody immunoassay. This study was aimed to determine the performance of HIV combination assays in Taiwan, where the HIV-1 seroprevalence is 0.007% and HIV-2 infection has never been reported. Performance of three fourth-generation HIV Ag/Ab combination assays (Dia.Pro, Wantai, and Bio-Rad) and one third-generation HIV Ab immunoassay (AxSYM HIV 1/2 gO) was assessed. A total of 152 specimens, including 86 confirmed HIV-seropositive and 66 HIV-seronegative samples, were used in the study. The sensitivity of four assays varied from 98.8% to 100%, and specificity varied from 98.5% to 100%. Performance of the 75 equivocal samples, the HIV status of which was confirmed later, in terms of negative prediction varied from 81.8% to 87.5%. The Bio-Rad and Dia.Pro assays exhibited higher sensitivity for the detection of p24 antigen among the three fourth-generation HIV combination assays. The three fourth-generation HIV Ag/Ab combination assays exhibited better sensitivity, specificity, and negative prediction than the third-generation HIV Ab immunoassay. Copyright © 2015. Published by Elsevier B.V.

  17. Detection of antibodies against Theiler's murine encephalomyelitis virus GDVII strain in experimental guinea pigs.

    Science.gov (United States)

    Häger, C; Glage, S; Held, N; Bleich, E M; Burghard, A; Mähler, M; Bleich, André

    2016-10-01

    A disease affecting guinea pigs called 'guinea pig lameness' characterized by clinical signs of depression, lameness of limbs, flaccid paralysis, weight loss and death within a few weeks was first described by Römer in 1911. After a research group in our facility kept laboratory guinea pigs from two different origins together in one room, lameness was observed in two animals. Further investigations revealed a serological immune response against Theiler's murine encephalomyelitis virus (TMEV; GDVII strain) in these animals. Histopathology of the lumbar spinal cord of these animals showed mononuclear cell infiltration and necrotic neurons in the anterior horn. Therefore, all guinea pigs from this contaminated animal unit, from other units in our facility, as well as from different European institutions and breeding centres were screened for antibodies directed against GDVII. Our investigations showed that approximately 80% of all guinea pigs from the contaminated animal unit were seropositive for GDVII, whereas animals from other separate units were completely negative. In addition, 43% of tested sera from the different European institutions and breeding centres contained antibodies against GDVII. The present data confirm that an unknown viral infection causes an immune response in experimental guinea pigs leading to seroconversion against GDVII and that guinea pigs from a commercial breeder are the source of the infection. © The Author(s) 2015.

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

    Directory of Open Access Journals (Sweden)

    Rekha Khandia

    2018-04-01

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

  19. Development and characterization of neutralizing monoclonal antibodies against canine distemper virus hemagglutinin protein.

    Science.gov (United States)

    Bi, Zhenwei; Xia, Xingxia; Wang, Yongshan; Mei, Yongjie

    2015-04-01

    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. © 2015 The Societies and Wiley Publishing Asia Pty Ltd.

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

    Science.gov (United States)

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

    2017-08-01

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

  1. Frequency of anti hepatitis C virus antibodies amongst sanitary workers in a tertiary care hospital in Pakistan

    International Nuclear Information System (INIS)

    Khan, A.Z.; Razzaq, K.; Ansari, J.K.; Niazzi, S.K.

    2011-01-01

    Objective: To determine the frequency of anti Hepatitis C Virus antibodies in sanitary workers at Military Hospital Rawalpindi and to identify additional risk factors in them for hepatitis C infection. Cross sectional study Place and Duration of Study: Department of medicine, Military Hospital (M.H.), Rawalpindi, Pakistan over six months. Patients and Methods: All sanitary workers working at Military Hospital Rawalpindi were tested for anti HCV antibodies by third generation ELISA. Results: Six percent of the study population was found to be positive for anti HCV antibodies. Conclusion: The frequency of anti HCV antibodies is fairly high in sanitary workers, working in this tertiary care hospital studied. HCV infection is more frequent in those sanitary workers who have longer duration of service. (author)

  2. Antibody levels to hepatitis E virus in North Carolina swine workers, non-swine workers, swine, and murids.

    Science.gov (United States)

    Withers, Mark R; Correa, Maria T; Morrow, Morgan; Stebbins, Martha E; Seriwatana, Jitvimol; Webster, W David; Boak, Marshall B; Vaughn, David W

    2002-04-01

    In a cross-sectional serosurvey, eastern North Carolina swine workers (n = 165) were compared with non-swine workers (127) for the presence of antibodies to hepatitis E virus as measured by a quantitative immunoglobulin enzyme-linked immunosorbent assay. Using a cutoff of 20 Walter Reed U/ml, swine-exposed subjects had a 4.5-fold higher antibody prevalence (10.9%) than unexposed subjects (2.4%). No evidence of past clinical hepatitis E or unexplained jaundice could be elicited. Swine (84) and mice (61), from farm sites in the same region as exposed subjects, were also tested. Antibody prevalence in swine (overall = 34.5%) varied widely (10.0-91.7%) according to site, but no antibody was detected in mice. Our data contribute to the accumulating evidence that hepatitis E may be a zoonosis and specifically to the concept of it as an occupational infection of livestock workers.

  3. Prevalence of Antibodies Against Foot-and-Mouth Disease Virus in Cattle in Kasese and Bushenyi Districts in Uganda

    DEFF Research Database (Denmark)

    Mwiine, F. N.; Ayebazibwe, C.; Olaho-Mukani, W.

    2010-01-01

    Abstract: The aim of this study was to determine the seroprevalence and serotype-specificity of the circulating antibodies against Foot-and-Mouth Disease Virus (FMDV) in cattle in K asese and Bushenyi districts in Uganda. A total of 309 serum samples were collected and tested for antibodies against...... Non-Structural (NS) and Structural Proteins (SP) using Ceditest® FMDV-NS and C editest® FMDV type O test kits. Seroprevalences were much higher in Kasese in both tests (61 and 43%, respectively) than in Bushenyi (3 and 4% , respectively). A high proportion of sera, that tested positive in the NSP test......, were subjected to seven serotype specific blocking ELISAs for antibodies against the seven FMDV serotypes (O, A, C, Asia 1, SAT 1, SAT 2 and SAT 3). The study showed presence of antibodies against four FMDV serotypes with decreasing magnitude as follows: O> SAT 1> SAT 3/SAT 2. It is recommended...

  4. The relationship between antibody status to bovine corona virus and bovine respiratory syncytial virus and disease incidence, reproduction and herd characteristics in dairy herds

    Directory of Open Access Journals (Sweden)

    Tråvén Madeleine

    2010-06-01

    Full Text Available Abstract Background Bovine respiratory syncytial virus (BRSV and bovine corona virus (BCV affects cattle worldwide. Our objective was to evaluate the effects of these infections on general health and reproduction parameters measurable on herd level and to explore the association between antibody status and some herd characteristics. Methods We collected a pooled milk sample from five primiparous cows from 79 Swedish dairy herds in September 2006. The samples were analysed for immunoglobulin G antibodies to BCV and BRSV with indirect enzyme-linked immunosorbent assays. Herd level data from 1 September 2005 to 30 August 2006 were accessed retrospectively. The location of the herds was mapped using a geographical information system. Results Ten herds were antibody negative to both viruses and were compared with 69 herds positive to BCV or BRSV or both. Positive herds had a higher (P = 0.001 bulk tank milk somatic cell count (BMSCC compared with negative herds. The medians for all other analyzed health and reproductive parameters were consistently in favour of the herds negative to both viruses although the differences were not statistically significant. A higher proportion (P = 0.01 of herds used professional technicians for artificial insemination, rather than farm personnel, amongst the 33 herds negative to BCV compared with the 46 positive herds. Conclusions Our result shows that herds that were antibody positive to BCV and/or BRSV had a higher BMSCC compared with herds negative to BCV and BRSV. There was also tendency that negative herds had a better general herd health compared with positive. A higher proportion amongst the BCV negative herds used external technicians for AI instead of farm personnel, indicating that it is possible to avoid infection although having regular visits. Negative herds were located in close proximity to positive herds, indicating that local spread and airborne transmission between herds might not be of great

  5. A rapid radioimmunoassay using 125I-labeled staphylococcal protein A for antibody to varicella-zoster virus

    International Nuclear Information System (INIS)

    Richman, D.D.; Cleveland, P.H.; Oxman, M.N.; Zaia, J.A.

    1981-01-01

    A sensitive radioimmunoassay for serum antibody to varicella-zoster virus is described; it uses 125I-labeled staphylococcal protein A and a specially designed immunofiltration apparatus. The assay accurately distinguishes between individuals who are susceptible and those who are immune to infection with varicella-zoster virus. In addition, it can detect passive antibody in recipients of varicella-zoster immune globulin. This radioimmunoassay also detects the heterologous antibody responses that occasionally occur in patients infected with herpes simplex virus, which also have been detected by other antibody assays. The particular advantages of this assay are the use of noninfectious reagents, the speed of execution (less than 3 hr), the requirement for only small quantities of serum (30 microliters), the objectivity of end-point determination, and the capability of screening large numbers of sera. Consequently, this radioimmunoassay is especially useful for the rapid identification of susceptible individuals, which is essential for the appropriate management of patients and hospital personnel after exposure to varicella

  6. Antibody response in the female rabbit reproductive tract to influenza haemagglutinin encoded by a recombinant myxoma virus

    International Nuclear Information System (INIS)

    Gu Wenyi; Holland, Michael; Janssens, Peter; Kerr, Peter

    2003-01-01

    The antibody response in serum and the reproductive tract of female rabbits to a model antigen, influenza virus haemagglutinin (HA), encoded by a recombinant myxoma virus was investigated. Strong and lasting IgG antibody responses to HA were induced in serum following intradermal, intranasal, and intravaginal immunisations. HA IgG was also detected in reproductive tract fluids but was only about 1% the titer of that in serum. HA IgA was not detected in serum of any infected groups and was occasionally detected in reproductive tract fluids at a low titer only after infections through mucosal sites. HA IgM was also detected only in some of the reproductive tract fluids at very low levels. Induction of ovulation did not change these patterns and B cell homing to the reproductive tract was not profound. In contrast, HA IgG and IgM titers in ovarian follicular fluids were comparable to that in serum. These data suggest that if this virus is used to deliver an immunocontraceptive vaccine that requires a high-level antibody response, the target antigen needs to be accessible to serum antibody or in the ovary

  7. A novel monoclonal antibody for detection of galectin-9 in tissue sections: application to human tissues infected by oncogenic viruses

    Directory of Open Access Journals (Sweden)

    Barjon Clément

    2012-07-01

    Full Text Available Abstract Background Galectin-9 is a mammalian lectin which possesses immunosuppressive properties. Excessive production of galectin-9 has been reported in two types of human virus-associated diseases chronic hepatitis C and nasopharyngeal carcinoma associated to the Epstein-Barr virus. The objective of this study was to produce new monoclonal antibodies targeting galectin-9 in order to improve its detection in clinical samples, especially on tissue sections analysed by immunohistochemistry. Methods Hybridomas were produced through immunization of mice with the recombinant c-terminus part of galectin-9 (residues 191 to 355 of the long isoform and semi-solid fusion of spleen cells with Sp2/0 cells. Monoclonal antibodies were characterized using ELISA, epitope mapping, western blot and immunohistochemistry. Results We selected seven hybridomas producing antibodies reacting with our recombinant c-terminus galectin-9 in ELISA. Five of them reacted with the epitope “TPAIPPMMYPHPA” (common to all isoforms, residues 210 to 222 of the long isoform and stained all three isoforms of galectin-9 analysed by western blot. One of them, 1G3,demonstrated very good sensitivity and specificity when used for immunohistochemistry. Using 1G3, we could confirm the intense and constant expression of galectin-9 by Epstein-Barr virus positive malignant cells from nasopharyngeal carcinomas. In most samples, specific staining was detected in both cytoplasm and nuclei. Galectin-9 was also detected in liver biopsies from patients infected by the human hepatitis C or B viruses with expression not only in inflammatory leucocytes and Kupffer cells, but also in hepatocytes. In contrast, galectin-9 was virtually absent in non-infected liver specimens. Conclusion The 1G3 monoclonal antibody will be a powerful tool to assess galectin-9 expression and distribution especially in diseases related to oncogenic viruses.

  8. A Potent Virus-Specific Antibody-Secreting Cell Response to Acute Enterovirus 71 Infection in Children.

    Science.gov (United States)

    Huang, Kuan-Ying Arthur; Lin, Jainn-Jim; Chiu, Cheng-Hsun; Yang, Shuan; Tsao, Kuo-Chien; Huang, Yhu-Chering; Lin, Tzou-Yien

    2015-09-01

    Enterovirus 71 (EV71) remains a leading pathogen for acute infectious diseases in children, especially in Asia. The cellular basis for establishing a virus-specific antibody response to acute EV71 infections is unclear in children. We studied the magnitude of virus-specific antibody-secreting B cells (ASCs) and its relationship with serological response, clinical parameters, and virological parameters among children with laboratory-confirmed EV71 infection. A potent EV71 genogroup B- and virus-specific ASC response was detected in the first week of illness among genotype B5 EV71-infected children. The cross-reactive EV71-specific ASC response to genogroup C viral antigens composed about 10% of the response. The EV71-specific ASC response in children aged ≥3 years produced immunoglobulin G predominantly, but immunoglobulin M was predominant in younger children. Proliferation marker was expressed by the majority of circulating ASCs in the acute phase of EV71 infection. Virus-specific ASC responses significantly correlated with throat viral load, fever duration, and serological genogroup-specific neutralization titer. The presence of a virus-specific ASC response serves an early cellular marker of an EV71-specific antibody response. Further detailed study of EV71-specific ASCs at the monoclonal level is crucial to delineate the specificity and function of antibody immunity in children. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  9. Antibody Tracing, Seroepidemiology and Risk Factors of Bovine Respiratory Syncytial Virus and Bovine Adenovirus-3 in Dairy Holstein Farms

    Directory of Open Access Journals (Sweden)

    Mahsa FARZINPOUR

    2016-01-01

    Full Text Available Antibody tracing, risk factors and seroepidemiology of bovine respiratory syncytial virus and bovine adenovirus-3 were investigated in 22 Industrial and Semi-Industrial dairy Holstein farms. Serum samples (n=736 from various ages of unvaccinated cows were collected from May to September 2012. Risk factors including age, past history of respiratory diseases, amount of milk production, husbandry type and herd size were considered. Data were analyzed by Chi-square and logistic regression. Results indicated that the infection with some of individual viruses was related to past history of respiratory disease and herd size. No specific pattern was seen on the effect of level of milk production on seropositivity of animals. The seroprevalence for BRSV and BAV-3 were 89.1% and 88%, respectively. The present study indicates that infections of bovine respiratory viruses frequently occur in cattle of Fars province and the main viral cause of primary occurrence of respiratory diseases may be due to aforementioned viruses.

  10. Development of electrochemical immunosensors based on different serum antibody immobilization methods for detection of Japanese encephalitis virus

    International Nuclear Information System (INIS)

    Tran, Quang Huy; Hanh Nguyen, Thi Hong; Phan, Thi Nga; Mai, Anh Tuan; Nguyen, Thi Thuy; Vu, Quang Khue

    2012-01-01

    This paper describes the development of electrochemical immunosensors based on human serum antibodies with different immobilization methods for detection of Japanese encephalitis virus (JEV). Human serum containing anti-JEV antibodies was used to immobilize onto the surface of silanized interdigitated electrodes by four methods: direct adsorption (APTES-serum), covalent binding with a cross linker of glutaraldehyde (APTES-GA-serum), covalent binding with a cross linker of glutaraldehyde combined with anti-human IgG (APTES-GA-anti-HIgG-serum) and covalent binding with a cross linker of glutaraldehyde combined with a bioaffinity of protein A (APTES-GA-PrA-serum). Atomic force microscopy was used to verify surface characteristics of the interdigitated electrodes before and after treatment with serum antibodies. The output signal of the immunosensors was measured by the change of conductivity resulting from the specific binding of JEV antigens and serum antibodies immobilized on the electrodes, with the help of horseradish peroxidase (HRP)-labeled secondary antibody against JEV. The results showed that the APTES-GA-PrA-serum method provided the highest signal of the electrochemical immunosensor for detection of JEV antigens, with the linear range from 25 ng ml −1 to 1 μg ml −1 , and the limit of detection was about 10 ng ml −1 . This study shows a potential development of novel electrochemical immunosensors applied for virus detection in clinical samples in case of possible outbreaks

  11. Detection of hepatitis B virus infection in HBsAg-negative patients by monoclonal antibodies against HBsAg

    International Nuclear Information System (INIS)

    Fujita, Y.K.

    1986-01-01

    The technique of producing antibody secreting hybridomas has made available high-affinity antibodies of predefined specificity for use as diagnostic reagents. Recently, high-affinity monoclonal antibodies to hepatitis B surface antigens (HBsAg) were produced and characterized. Immunoassay was developed using these antibodies for the detection of HBsAg-associated determinants. The present study indicated the significance of the enhanced detection by monoclonal radioimmunoassay (M-RIA) of HBsAg in sera of patients with hepatitis B virus infection. The M-RIA detected HBsAg in sera of hemodialysis patients and blood donor defined as HBsAg-negative by polyclonal RIA (2.2 %, 0.14 %, respectively). Furthermore, individuals with chronic liver diseases were reactive only in the M-RIA (chronic hepatitis 4.8 %, liver cirrhosis 10.0 %, hepatocellular carcinoma 22.2 %). It is noteworthy that some of these patients were diagnosesed as so-called non-A non-B hepatitis because of no serological markers of hepatitis B virus infection such as HBsAb and HBcAb. The enhanced performance of the monoclonal RIA compared to conventional RIA was due to the increased sensitivity of the assay (55 pg vs 230 pg/ml). In immunohistochemical study, one of the monoclonal antibody named 5C3 was applied for detection of HBsAg in the formalin-fixed paraffin-embedded liver. HBsAg was detected in 6 out of 41 HBsAg-seronegative liver specimen. Thus, the studies showed the importance of the clinical application of monoclonal antibodies such as immunoassay and immunohistochemical study in the diagnosis of hepatitis B virus infection. (author)

  12. Detection of hepatitis B virus infection in HBsAg-negative patients by monoclonal antibodies against HBsAg

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Y K

    1986-11-01

    The technique of producing antibody secreting hybridomas has made available high-affinity antibodies of predefined specificity for use as diagnostic reagents. Recently, high-affinity monoclonal antibodies to hepatitis B surface antigens (HBsAg) were produced and characterized. Immunoassay was developed using these antibodies for the detection of HBsAg-associated determinants. The present study indicated the significance of the enhanced detection by monoclonal radioimmunoassay (M-RIA) of HBsAg in sera of patients with hepatitis B virus infection. The M-RIA detected HBsAg in sera of hemodialysis patients and blood donor defined as HBsAg-negative by polyclonal RIA (2.2 %, 0.14 %, respectively). Furthermore, individuals with chronic liver diseases were reactive only in the M-RIA (chronic hepatitis 4.8 %, liver cirrhosis 10.0 %, hepatocellular carcinoma 22.2 %). It is noteworthy that some of these patients were diagnosesed as so-called non-A non-B hepatitis because of no serological markers of hepatitis B virus infection such as HBsAb and HBcAb. The enhanced performance of the monoclonal RIA compared to conventional RIA was due to the increased sensitivity of the assay (55 pg vs 230 pg/ml). In immunohistochemical study, one of the monoclonal antibody named 5C3 was applied for detection of HBsAg in the formalin-fixed paraffin-embedded liver. HBsAg was detected in 6 out of 41 HBsAg-seronegative liver specimen. Thus, the studies showed the importance of the clinical application of monoclonal antibodies such as immunoassay and immunohistochemical study in the diagnosis of hepatitis B virus infection.

  13. Structure-Based Design of Hepatitis C Virus Vaccines That Elicit Neutralizing Antibody Responses to a Conserved Epitope

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, Brian G.; Boucher, Elisabeth N.; Piepenbrink, Kurt H.; Ejemel, Monir; Rapp, Chelsea A.; Thomas, William D.; Sundberg, Eric J.; Weng, Zhiping; Wang, Yang; Diamond, Michael S.

    2017-08-09

    Despite recent advances in therapeutic options, hepatitis C virus (HCV) remains a severe global disease burden, and a vaccine can substantially reduce its incidence. Due to its extremely high sequence variability, HCV can readily escape the immune response; thus, an effective vaccine must target conserved, functionally important epitopes. Using the structure of a broadly neutralizing antibody in complex with a conserved linear epitope from the HCV E2 envelope glycoprotein (residues 412 to 423; epitope I), we performed structure-based design of immunogens to induce antibody responses to this epitope. This resulted in epitope-based immunogens based on a cyclic defensin protein, as well as a bivalent immunogen with two copies of the epitope on the E2 surface. We solved the X-ray structure of a cyclic immunogen in complex with the HCV1 antibody and confirmed preservation of the epitope conformation and the HCV1 interface. Mice vaccinated with our designed immunogens produced robust antibody responses to epitope I, and their serum could neutralize HCV. Notably, the cyclic designs induced greater epitope-specific responses and neutralization than the native peptide epitope. Beyond successfully designing several novel HCV immunogens, this study demonstrates the principle that neutralizing anti-HCV antibodies can be induced by epitope-based, engineered vaccines and provides the basis for further efforts in structure-based design of HCV vaccines.

    IMPORTANCEHepatitis C virus is a leading cause of liver disease and liver cancer, with approximately 3% of the world's population infected. To combat this virus, an effective vaccine would have distinct advantages over current therapeutic options, yet experimental vaccines have not been successful to date, due in part to the virus's high sequence variability leading to immune escape. In this study, we rationally designed several vaccine immunogens based on the structure of a conserved epitope that

  14. Generation and Characterization of Monoclonal Antibodies against a Cyclic Variant of Hepatitis C Virus E2 Epitope 412-422

    Science.gov (United States)

    Sandomenico, Annamaria; Leonardi, Antonio; Berisio, Rita; Sanguigno, Luca; Focà, Giuseppina; Focà, Annalia; Ruggiero, Alessia; Doti, Nunzianna; Muscariello, Livio; Barone, Daniela; Farina, Claudio; Owsianka, Ania; Vitagliano, Luigi

    2016-01-01

    ABSTRACT The hepatitis C virus (HCV) E2 envelope glycoprotein is crucial for virus entry into hepatocytes. A conserved region of E2 encompassing amino acids 412 to 423 (epitope I) and containing Trp420, a residue critical for virus entry, is recognized by several broadly neutralizing antibodies. Peptides embodying this epitope I sequence adopt a β-hairpin conformation when bound to neutralizing monoclonal antibodies (MAbs) AP33 and HCV1. We therefore generated new mouse MAbs that were able to bind to a cyclic peptide containing E2 residues 412 to 422 (C-epitope I) but not to the linear counterpart. These MAbs bound to purified E2 with affinities of about 50 nM, but they were unable to neutralize virus infection. Structural analysis of the complex between C-epitope I and one of our MAbs (C2) showed that the Trp420 side chain is largely buried in the combining site and that the Asn417 side chain, which is glycosylated in E2 and solvent exposed in other complexes, is slightly buried upon C2 binding. Also, the orientation of the cyclic peptide in the antibody-combining site is rotated by 180° compared to the orientations of the other complexes. All these structural features, however, do not explain the lack of neutralization activity. This is instead ascribed to the high degree of selectivity of the new MAbs for the cyclic epitope and to their inability to interact with the epitope in more flexible and extended conformations, which recent data suggest play a role in the mechanisms of neutralization escape. IMPORTANCE Hepatitis C virus (HCV) remains a major health care burden, affecting almost 3% of the global population. The conserved epitope comprising residues 412 to 423 of the viral E2 glycoprotein is a valid vaccine candidate because antibodies recognizing this region exhibit potent neutralizing activity. This epitope adopts a β-hairpin conformation when bound to neutralizing MAbs. We explored the potential of cyclic peptides mimicking this structure to elicit

  15. Effective multiple oral administration of reverse genetics engineered infectious bursal disease virus in mice in the presence of neutralizing antibodies.

    Science.gov (United States)

    Hornyák, Ákos; Lipinski, Kai S; Bakonyi, Tamás; Forgách, Petra; Horváth, Ernő; Farsang, Attila; Hedley, Susan J; Palya, Vilmos; Bakács, Tibor; Kovesdi, Imre

    2015-01-01

    Despite spectacular successes in hepatitis B and C therapies, severe hepatic impairment is still a major treatment problem. The clinically tested infectious bursal disease virus (IBDV) superinfection therapy promises an innovative, interferon-free solution to this great unmet need, provided that a consistent manufacturing process preventing mutations or reversions to virulent strains is obtained. To address safety concerns, a tissue culture adapted IBDV vaccine strain V903/78 was cloned into cDNA plasmids ensuring reproducible production of a reverse engineered virus R903/78. The therapeutic drug candidate was characterized by immunocytochemistry assay, virus particle determination and immunoblot analysis. The biodistribution and potential immunogenicity of the IBDV agent was determined in mice, which is not a natural host of this virus, by quantitative detection of IBDV RNA by a quantitative reverse transcriptase-polymerase chain reaction and virus neutralization test, respectively. Several human cell lines supported IBDV propagation in the absence of visible cytopathic effect. The virus was stable from pH 8 to pH 6 and demonstrated significant resistance to low pH and also proved to be highly resistant to high temperatures. No pathological effects were observed in mice. Single and multiple oral administration of IBDV elicited antibodies with neutralizing activities in vitro. Repeat oral administration of R903/78 was successful despite the presence of neutralizing antibodies. Single oral and intravenous administration indicated that IBDV does not replicate in mammalian liver alleviating some safety related concerns. These data supports the development of an orally delivered anti-hepatitis B virus/ anti-hepatitis C virus viral agent for human use. Copyright © 2015 John Wiley & Sons, Ltd.

  16. Effect of using heat-inactivated serum with the Abbott human T-cell lymphotropic virus type III antibody test.

    OpenAIRE

    Jungkind, D L; DiRenzo, S A; Young, S J

    1986-01-01

    The Abbott enzyme immunoassay (Abbott Laboratories, North Chicago, Ill.) for human T-cell lymphotropic virus type III (HTLV-III) antibody was evaluated to determine the effect of using heat-inactivated (56 degrees C for 30 min) serum as the sample. Each of 58 nonreactive serum samples gave a higher A492 value when tested after heat inactivation. Ten of the samples became reactive after heating. Heat-inactivated serum should not be used in the current Abbott HTLV-III antibody test, because thi...

  17. Specific detection of peste des petits ruminants virus antibodies in sheep and goat sera by the luciferase

    International Nuclear Information System (INIS)

    Berguido, F.J.; Bodjo, S.C.; Loitsch, A.; Diallo, A.

    2016-01-01

    Full text: Peste des petits ruminants (PPR) is a contagious and often fatal transboundary animal disease affecting mostly sheep, goats and wild small ruminants. This disease is endemic in most of Africa, the Middle, Near East, and large parts of Asia. The casual agent is peste des petits ruminants virus (PPRV), which belongs to the genus Morbilivirus in the family Paramyxoviridae. This genus also includes measles virus (MV), canine distemper virus (CDV) and rinderpest virus (RPV). All are closely related viruses with serological cross reactivity. In this study, we have developed a Luciferase Immunoprecipitation System (LIPS) for the rapid detection of antibodies against PPRV in serum samples and for specific differentiation from antibodies against RPV. PPR and rinderpest (RP) serum samples were assayed by PPR-LIPS and two commercially available PPR cELISA tests. The PPR-LIPS showed high sensitivity and specificity for the samples tested and showed no cross reactivity with RPV unlike the commercial PPR cELISA tests which did not cross react with RPV. Based on the results shown in this study, PPR-LIPS is presented as a good candidate for the specific serosurveillance of PPR. (author)

  18. Obtaining a citric tristeza virus p65 protein antibody and preliminary results of p65 in vivo expression

    Directory of Open Access Journals (Sweden)

    Yanneth Torres

    2003-07-01

    Full Text Available The citric tristeza virus (CTV belongs to the Closteroviridae family which indudes the only vegetal viruses possessing genes homologous to HSP70 thermal cellular shock proteins in their genome. Such is the case of the gene encoding for the CTV p65 protein which presents high homology with the HSP70 protein family. It has been shown recently that HSP70h viral proteins (such as CTV p65 are involved both in viral assembly, as a microtubule binding protein, and in cell-cell movement. Since CTV is the most deleterious citrus pathogen, understanding this protein's role in the pathogenesis process is important. Rabbits were immunised with four synthetic peptides (corresponding to CTV p65 thermal shock protein's carboxyl-terminal region to obtain polyclonal antibodies. All the peptides used were immunogenic, even though two of them showed greater response. Whilst none of the antibodies obtained reacted to non-infected plant extract, the p65 proteins was detected in extracts taken from citric plants infected with CTV Based on the antibody's reaction to two Colombian isolates having different serological characteristics, the p65 antibody's immunological behaviour appeared to be independent of the symptomatic severity of the CTV isolates. It was shown that the ORF encoded for the HSP70 homologue in CTV was expressed in vivo, even though the p65 antibody was only detected in concentrated protein extracts taken from infected plants, supporting reports from other studies that the concentration of this protein in plants infected with CTV is low. This is the first time that a polyclonal CTV antibody has been obtained in Colombia against p65 (a protein intervening in viral assembly and movement. Adapting a technique for obtaining p65 antibodies by using synthetic peptides as immunogens could be useful in the future for detecting or diagnosing p65 proteins present in different Colombian CTV isolates, especially in developing studies contributing towards greater

  19. Polyclonal antibodies against the recombinantly expressed coat protein of the Citrus psorosis virus

    Directory of Open Access Journals (Sweden)

    Reda Salem

    2018-05-01

    Full Text Available Psorosis is a damaging disease of citrus that is widespread in many parts of the world. Citrus psorosis virus (CPsV, the type species of the genus Ophiovirus, is the putative causal agent of psorosis. Detection of CPsV by laboratory methods, serology in particular is a primary requirement for large-scale surveys but their production has been impaired by the difficulty of obtaining sufficient clean antigen for immunization. Specific PAbs against coat protein were produced in E. coli using recombinant DNA approach. The full length CP gene fragment was amplified by RT-PCR using total RNA extracted from CPsV infected citrus leaves and CP specific primers. The obtained product (1320bp was cloned, sequenced and sub-cloned into pET-30(+ expression vector. Expression was induced and screened in different bacterial clones by the presence of the expressed protein (48kDa and optimized in one clone. Expressed CP was purified using batch chromatography under denaturing conditions. Specificity of expressed protein was demonstrated by ELISA before used as antigen for raising PAbs in mice. Specificity of the raised PAbs to CPsV was verified by ELISA and western blotting. The raised PAbs were showed highly effectiveness in screening by ELISA comparing with the commercial antibodies purchased from Agritest, Valanzano, Italy.The expression of CPsV CP gene in E. coli, production of PAbs using recombinant protein as an antigen, the suitability of these antibodies for use in immunodiagnostics against the CPsV Egyptian isolate have been accomplished in this work. Keywords: CPsV, CP, PAbs, RT-PCR, ELISA, Western blotting

  20. Prevalence and distribution of Peste des petits ruminants virus antibodies in various districts of Tanzania.

    Science.gov (United States)

    Swai, Emmanuel Senyael; Kapaga, A; Kivaria, F; Tinuga, D; Joshua, G; Sanka, P

    2009-12-01

    Despite the widespread prevalence of infection with Peste des petits ruminants virus (PPRV) in goats and sheep industry in Asia and sub-Saharan Africa, there have been few, if any, structured population-based studies examining the epidemiology of this infection in Tanzania. In this study, we investigated the seroprevalence, and risk factors, of Peste des petitis ruminants(PPR) in sheep and goat flocks from seven different geographical administration authorities (Ngorongoro, Monduli, Longido, Karatu, Mbulu, Siha and Simanjiro) located in Northern Tanzania. Serum samples from 657 and 892 sheep and goats, respectively, corresponding to 91 sheep/goat flocks and 43 villages were collected. Competitive enzyme linked immunosorbent assay (c-ELISA) was used to detect the presence of antibodies in the serum against PPRV. Chi-square analysis and multivariable logistic regression model were used to identify risk factors for PPRV seropositivity. Findings suggested that the sero-positive cases were significantly higher in goats than in sheep (49.5% versus 39.8%; P=0.002). The overall seroprevalence of PPRV infection in small ruminants was 45.8%. Highest seroprevalence (42.6-88.02%) was observed in Mbulu, Siha, Longido, Ngorongoro districts, while antibodies less than 40% to none were found in serum from Monduli, Karatu and Simanjiro, respectively. These findings confirm natural transmission of PPRV under field condition for the first time in Tanzania. Results may be correlated with variations in the sheep and goat husbandry practices within different geographic localities, the uncontrolled movement of animals, the levels of natural immunity and the sharing of grazing field amongst agro and pastoralists.

  1. PEMERIKSAAN VIRUS DENGUE-3 PADA NYAMUK Aedes aegypti YANG DIINFEKSI SECARA INTRATHORAKAL DENGAN TEKNIK IMUNOSITOKIMIA MENGGUNAKAN ANTIBODI DSSE10

    Directory of Open Access Journals (Sweden)

    Dyah Widiastuti

    2013-09-01

    Full Text Available ABSTRACTDengue viruses, globally the most prevalent arboviruses, are transmitted to humans by persistently infectedAedes mosquitoes. The most important vector of Dengue virus is the mosquito Ae.aegypti, which should be the main targetof surveillance and control activities. Virologic surveillance for dengue viruses in its vector has been used as an earlywarning system to predict outbreaks. Detection of Dengue virus antigen in mosquito head squash usingimmunocytochemical streptavidin biotin peroxidase complex (SBPC assay is an alternative method for dengue vectorsurveillance. The study aimed to develope immunocytochemical SBPC assay to detect Dengue virus infection in headsquash of Ae.aegypti. The study design was experimental. Artificially-infected adult Ae. aegypti mosquitoes of DENV 3were used as infectious samples and non-infected adult Ae. aegypti mosquitoes were used as normal ones. Theimmunocytochemical SBPC assay using monoclonal antibody DSSE10 then was applied in mosquito head squash todetect Dengue virus antigen. The results were analyzed by descriptive analysis. The immunocytochemical SBPC assaycan detect Dengue virus antigen in mosquito head squash at day 2 postinfection. There are some false positive resultsfound in immunocytochemical SBPC assay.Key Word: Dengue, immunocytochemistry, DSSE10

  2. A serological survey for avian infectious bronchitis virus and Newcastle disease virus antibodies in backyard (free-range) village chickens in Mexico.

    Science.gov (United States)

    Gutierrez-Ruiz, E J; Ramirez-Cruz, G T; Camara Gamboa, E I; Alexander, D J; Gough, R E

    2000-12-01

    The commercial flocks in Yucatan, Mexico are free of Newcastle disease virus (NDV) in its velogenic viscerotropic form, but little is known about the disease status of backyard poultry. A seroprevalence survey in 30 villages using haemagglutination inhibition (HI) tests for infectious bronchitis virus (IBV) and NDV antibodies was carried out from December 1997 to June 1998. The seroprevalences were 56.5% (95% CI 50-63%) for IBV and 2.2% (95% CI 0.5-3.8%) for NDV. All the villages had chickens that were positive for antibodies to IBV and nine of the villages had chickens that were positive for antibodies to NDV. This suggests that IBV may be responsible for a large proportion of the respiratory disease observed in backyard chickens in Yucatan. The implications of these findings are discussed, including the highly susceptible status of the backyard chickens in Yucatan to NDV and the possibility of this virus being one cause of the syndrome known as mortandad by the local people.

  3. Comparison of a commercial ELISA and an immunoperoxidase monolayer assay to detect antibodies directed against porcine respiratory and reproductive syndrome virus

    NARCIS (Netherlands)

    Nodelijk, G.; Wensvoort, G.; Kroese, B.; Leengoed, van L.A.M.G.; Colijn, E.; Verheijden, J.H.M.

    1996-01-01

    A commercially available enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies against porcine respiratory and reproductive syndrome virus (PRRSV) was compared to an immunoperoxidase monolayer assay (IPMA). Serum samples used were collected from pigs experimentally infected with

  4. Isolation and characterization of broadly neutralizing human monoclonal antibodies to the e1 glycoprotein of hepatitis C virus

    DEFF Research Database (Denmark)

    Meunier, Jean-Christophe; Russell, Rodney S.; Goossens, Vera

    2008-01-01

    The relative importance of humoral and cellular immunity in the prevention or clearance of hepatitis C virus (HCV) infection is poorly understood. However, there is considerable evidence that neutralizing antibodies are involved in disease control. Here we describe the detailed analysis of human...... monoclonal antibodies (MAbs) directed against HCV glycoprotein E1, which may have the potential to control HCV infection. We have identified two MAbs that can strongly neutralize HCV-pseudotyped particles (HCVpp) bearing the envelope glycoproteins of genotypes 1a, 1b, 4a, 5a, and 6a and less strongly...... neutralize HCVpp bearing the envelope glycoproteins of genotype 2a. Genotype 3a was not neutralized. The epitopes for both MAbs were mapped to the region encompassing amino acids 313 to 327. In addition, robust neutralization was also observed against cell culture-adapted viruses of genotypes 1a and 2a...

  5. Fluorescence Adherence Inhibition Assay: A Novel Functional Assessment of Blocking Virus Attachment by Vaccine-Induced Antibodies.

    Directory of Open Access Journals (Sweden)

    Atul Asati

    Full Text Available Neutralizing antibodies induced by vaccination or natural infection play a critically important role in protection against the viral diseases. In general, neutralization of the viral infection occurs via two major pathways: pre- and post-attachment modes, the first being the most important for such infections as influenza and polio, the latter being significant for filoviruses. Neutralizing capacity of antibodies is typically evaluated by virus neutralization assays that assess reduction of viral infectivity to the target cells in the presence of functional antibodies. Plaque reduction neutralization test, microneutralization and immunofluorescent assays are often used as gold standard virus neutralization assays. However, these methods are associated with several important prerequisites such as use of live virus requiring safety precautions, tedious evaluation procedure and long assessment time. Hence, there is a need for a robust, inexpensive high throughput functional assay that can be performed rapidly using inactivated virus, without extensive safety precautions. Herein, we report a novel high throughput Fluorescence Adherence Inhibition assay (fADI using inactivated virus labeled with fluorescent secondary antibodies virus and Vero cells or erythrocytes as targets. It requires only few hours to assess pre-attachment neutralizing capacity of donor sera. fADI assay was tested successfully on donors immunized with polio, yellow fever and influenza vaccines. To further simplify and improve the throughput of the assay, we have developed a mathematical approach for calculating the 50% titers from a single sample dilution, without the need to analyze multi-point titration curves. Assessment of pre- and post-vaccination human sera from subjects immunized with IPOL®, YF-VAX® and 2013-2014 Fluzone® vaccines demonstrated high efficiency of the assay. The results correlated very well with microneutralization assay performed independently by the FDA

  6. Characterization of recombinant yellow fever-dengue vaccine viruses with human monoclonal antibodies targeting key conformational epitopes.

    Science.gov (United States)

    Lecouturier, Valerie; Berry, Catherine; Saulnier, Aure; Naville, Sophie; Manin, Catherine; Girerd-Chambaz, Yves; Crowe, James E; Jackson, Nicholas; Guy, Bruno

    2018-04-26

    The recombinant yellow fever-17D-dengue virus, live, attenuated, tetravalent dengue vaccine (CYD-TDV) is licensed in several dengue-endemic countries. Although the vaccine provides protection against dengue, the level of protection differs by serotype and warrants further investigation. We characterized the antigenic properties of each vaccine virus serotype using highly neutralizing human monoclonal antibodies (hmAbs) that bind quaternary structure-dependent epitopes. Specifically, we monitored the binding of dengue virus-1 (DENV-1; 1F4), DENV-2 (2D22) or DENV-3 (5J7) serotype-specific or DENV-1-4 cross-reactive (1C19) hmAbs to the four chimeric yellow fever-dengue vaccine viruses (CYD-1-4) included in phase III vaccine formulations using a range of biochemical and functional assays (dot blot, ELISA, surface plasmon resonance and plaque reduction neutralization assays). In addition, we used the "classic" live, attenuated DENV-2 vaccine serotype, immature CYD-2 viruses and DENV-2 virus-like particles as control antigens for anti-serotype-2 reactivity. The CYD vaccine serotypes were recognized by each hmAbs with the expected specificity, moreover, surface plasmon resonance indicated a high functional affinity interaction with the CYD serotypes. In addition, the hmAbs provided similar protection against CYD and wild-type dengue viruses in the in vitro neutralization assay. Overall, these findings demonstrate that the four CYD viruses used in clinical trials display key conformational and functional epitopes targeted by serotype-specific and/or cross-reactive neutralizing human antibodies. More specifically, we showed that CYD-2 displays serotype- specific epitopes present only on the mature virus. This indicates that the CYD-TDV has the ability to elicit antibody specificities which are similar to those induced by the wild type DENV. Future investigations will be needed to address the nature of CYD-TDV-induced responses after vaccine administration, and how these

  7. New sensitive and specific assay for human immunodeficiency virus antibodies using labeled recombinant fusion protein and time-resolved fluoroimmunoassay.

    OpenAIRE

    Siitari, H; Turunen, P; Schrimsher, J; Nunn, M

    1990-01-01

    A new, rapid method for the detection of human immunodeficiency virus type 1 (HIV-1) antibody by time-resolved fluoroimmunoassay (TR-FIA) was developed. In this assay format, microtitration strips were coated with a recombinant fusion protein, and the same protein was labeled with europium and added into the wells simultaneously with the test specimens. The recombinant fusion protein contained the HIV-1 p24 gag protein sequence that carried an insertion, near the carboxyl terminus, of a 23-am...

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

    Directory of Open Access Journals (Sweden)

    Xuesong Li

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

  9. Development and evaluation of a blocking enzyme-linked immunosorbent assay and virus neutralization assay to detect antibodies to viral hemorrhagic septicemia virus

    Science.gov (United States)

    Wilson, Anna; Goldberg, Tony; Marcquenski, Susan; Olson, Wendy; Goetz, Frederick; Hershberger, Paul; Hart, Lucas M.; Toohey-Kurth, Kathy

    2014-01-01

    Viral hemorrhagic septicemia virus (VHSV) is a target of surveillance by many state and federal agencies in the United States. Currently, the detection of VHSV relies on virus isolation, which is lethal to fish and indicates only the current infection status. A serological method is required to ascertain prior exposure. Here, we report two serologic tests for VHSV that are nonlethal, rapid, and species independent, a virus neutralization (VN) assay and a blocking enzyme-linked immunosorbent assay (ELISA). The results show that the VN assay had a specificity of 100% and sensitivity of 42.9%; the anti-nucleocapsid-blocking ELISA detected nonneutralizing VHSV antibodies at a specificity of 88.2% and a sensitivity of 96.4%. The VN assay and ELISA are valuable tools for assessing exposure to VHSV.

  10. Development and application of triple antibody sandwich enzyme-linked immunosorbent assays for begomovirus detection using monoclonal antibodies against Tomato yellow leaf curl Thailand virus.

    Science.gov (United States)

    Seepiban, Channarong; Charoenvilaisiri, Saengsoon; Warin, Nuchnard; Bhunchoth, Anjana; Phironrit, Namthip; Phuangrat, Bencharong; Chatchawankanphanich, Orawan; Attathom, Supat; Gajanandana, Oraprapai

    2017-05-30

    Tomato yellow leaf curl Thailand virus, TYLCTHV, is a begomovirus that causes severe losses of tomato crops in Thailand as well as several countries in Southeast and East Asia. The development of monoclonal antibodies (MAbs) and serological methods for detecting TYLCTHV is essential for epidemiological studies and screening for virus-resistant cultivars. The recombinant coat protein (CP) of TYLCTHV was expressed in Escherichia coli and used to generate MAbs against TYLCTHV through hybridoma technology. The MAbs were characterized and optimized to develop triple antibody sandwich enzyme-linked immunosorbent assays (TAS-ELISAs) for begomovirus detection. The efficiency of TAS-ELISAs for begomovirus detection was evaluated with tomato, pepper, eggplant, okra and cucurbit plants collected from several provinces in Thailand. Molecular identification of begomoviruses in these samples was also performed through PCR and DNA sequence analysis of the CP gene. Two MAbs (M1 and D2) were generated and used to develop TAS-ELISAs for begomovirus detection. The results of begomovirus detection in 147 field samples indicated that MAb M1 reacted with 2 begomovirus species, TYLCTHV and Tobacco leaf curl Yunnan virus (TbLCYnV), whereas MAb D2 reacted with 4 begomovirus species, TYLCTHV, TbLCYnV, Tomato leaf curl New Delhi virus (ToLCNDV) and Squash leaf curl China virus (SLCCNV). Phylogenetic analyses of CP amino acid sequences from these begomoviruses revealed that the CP sequences of begomoviruses recognized by the narrow-spectrum MAb M1 were highly conserved, sharing 93% identity with each other but only 72-81% identity with MAb M1-negative begomoviruses. The CP sequences of begomoviruses recognized by the broad-spectrum MAb D2 demonstrated a wider range of amino acid sequence identity, sharing 78-96% identity with each other and 72-91% identity with those that were not detected by MAb D2. TAS-ELISAs using the narrow-specificity MAb M1 proved highly efficient for the detection of

  11. Helicobacter pylori, hepatitis viruses A, C, E antibodies and HBsAg-prevalence and associated risk factors in pediatric communities of karachi

    International Nuclear Information System (INIS)

    Aziz, S.; Muzzafar, R.; Hafiz, S.; Abbas, Z.; Zafar, M.N.; Naqvi, S.A.A.; Rizvi, S.A.U.H.

    2007-01-01

    To document the prevalence of Helicobacter pylori (H. pylori), Hepatitis A virus (HAV), Hepatitis C virus (HCV), Hepatitis E virus (HEV) antibodies and Hepatitis B virus surface antigen (HBsAg), in the pediatric age group of low socioeconomic urban communities of Karachi and to identify risk factors associated with these infections. Three hundred and eighty children, ages 5 months to 15 years were investigated. Venous blood samples were collected and questionnaire filled on sociodemographic characteristics (family income, number of dependents in the family, area of living, number of people per room per house, and number of children sharing bed with parents and siblings). Gastrointestinal symptoms were recorded. Anti-HAV IgG (Hepatitis A virus IgG antibody), anti-HCV (Hepatitis C virus antibody), anti-HEV (Hepatitis E antibodies) and HBsAg, were analyzed by enzyme immunoassays (EIAs). Samples were also screened for anti-HIV1/2 (human immunodeficiency virus 1 and 2 antibodies by EIA. IgG antibodies against H. pylori were detected by immunochromatography. A correlation between increasing age and seroconversion was seen for hepatotropic viruses. At 14 years and above,100% of the children were found to be positive for anti-HAV, 26% for anti-HEV, and 1.4%, for anti-HCV while HBsAg was positive in 1.9%. H. pylori infection did not show a significant increase with age. Both anti-HAV and anti-H. pylori were present simultaneously in 30% of the population investigated. With age, increasing number of children acquired antibodies against hepatotropic viruses and H. pylori. Occurrence of HBsAg and anti-HEV at a later age suggests horizontal, rather than vertical transmission. (author)

  12. Antibody responses in humans infected with newly emerging strains of West Nile Virus in Europe.

    Directory of Open Access Journals (Sweden)

    Stefan Chabierski

    Full Text Available Infection with West Nile Virus (WNV affects an increasing number of countries worldwide. Although most human infections result in no or mild flu-like symptoms, the elderly and those with a weakened immune system are at higher risk for developing severe neurological disease. Since its introduction into North America in 1999, WNV has spread across the continental United States and caused annual outbreaks with a total of 36,000 documented clinical cases and ∼1,500 deaths. In recent years, outbreaks of neuroinvasive disease also have been reported in Europe. The WNV strains isolated during these outbreaks differ from those in North America, as sequencing has revealed that distinct phylogenetic lineages of WNV concurrently circulate in Europe, which has potential implications for the development of vaccines, therapeutics, and diagnostic tests. Here, we studied the human antibody response to European WNV strains responsible for outbreaks in Italy and Greece in 2010, caused by lineage 1 and 2 strains, respectively. The WNV structural proteins were expressed as a series of overlapping fragments fused to a carrier-protein, and binding of IgG in sera from infected persons was analyzed. The results demonstrate that, although the humoral immune response to WNV in humans is heterogeneous, several dominant peptides are recognized.

  13. Antibody Detection to Feline Immunodeficiency virus (FIV in stray cats in Ahvaz, southwestern Iran

    Directory of Open Access Journals (Sweden)

    Mosallanejad, B.

    2010-01-01

    Full Text Available The present study was performed to determine the prevalence of FIV in stray cat's population of Ahvaz different area. Serum samples were collected from 90 cats from 2005 to 2007. The studied cats were divided into two age groups (3 years and based on clinical signs (such as lymphadenopathy, periodontal diseases, gingivitis, abscess and cashecsi into two groups also. The results were analyzed using Fischer's exact test and Chi-square analysis. Prevalence to FIV antibodies in these cats was 15.55% (14 of 90 by means of ELISA Test Kit, indicating that this virus is present in the ecosystem. The infection had more prevalence in cats above 3 years (78.6%; 11 of 14 compared with cats less than 3 years (21.4%; 3 of 14. Statistical analysis showed significant difference between different age groups (P0.05. Three out of 12 cases (25% which had clinical signs and 11 out of 78 cases (14.1% which hadn’t clinical signs were seropositive. There was no significant difference between the two groups also (P>0.05. This study showed that FIV exist among cat's population of Ahvaz area and separation of companion and stray cats is very important for prevention of disease transmission to companion cats.

  14. Evaluation of Nobuto filter paper strips for the detection of avian influenza virus antibody in waterfowl

    Science.gov (United States)

    Dusek, Robert J.; Hall, Jeffrey S.; Nashold, Sean W.; Teslaa, Joshua L.; Ip, Hon S.

    2011-01-01

    The utility of using Nobuto paper strips for the detection of avian influenza antibodies was examined in mallards (Anas platyrhynchos) experimentally infected with low pathogenic avian influenza viruses. Blood was collected 2 wk after infection and was preserved either as serum or whole blood absorbed onto Nobuto strips. Analysis of samples using a commercially available blocking enzyme-linked immunosorbent assay revealed comparable results (???96% sensitivity for all methods) between sera stored at -30 C and the Nobuto strip preservation method even when the Nobuto strips were stored up to 3 mo at room temperature (RT). Significant differences were detected in the ratio of sample absorbance to negative control absorbance for Nobuto strips stored at RT compared with sera stored at -30 C, although these differences did not affect the ability of the test to reliably detect positive and negative samples. Nobuto strips are a convenient and sensitive alternative to the collection of serum samples when maintaining appropriate storage temperatures is difficult. ?? 2011 American Association of Avian Pathologists.

  15. Inter-laboratory study to characterize the detection of serum antibodies against porcine epidemic diarrhoea virus.

    Science.gov (United States)

    Strandbygaard, Bertel; Lavazza, Antonio; Lelli, Davide; Blanchard, Yannick; Grasland, Béatrice; Poder, Sophie Le; Rose, Nicolas; Steinbach, Falko; van der Poel, Wim H M; Widén, Frederik; Belsham, Graham J; Bøtner, Anette

    2016-12-25

    Porcine epidemic diarrhea virus (PEDV) has caused extensive economic losses to pig producers in many countries. It was recently introduced, for the first time, into North America and outbreaks have occurred again in multiple countries within Europe as well. To assess the properties of various diagnostic assays for the detection of PEDV infection, multiple panels of porcine sera have been shared and tested for the presence of antibodies against PEDV in an inter-laboratory ring trial. Different laboratories have used a variety of "in house" ELISAs and also one commercial assay. The sensitivity and specificity of each assay has been estimated using a Bayesian analysis applied to the ring trial results obtained with the different assays in the absence of a gold standard. Although different characteristics were found, it can be concluded that each of the assays used can detect infection of pigs at a herd level by either the early European strains of PEDV or the recently circulating strains (INDEL and non-INDEL). However, not all the assays seem suitable for demonstrating freedom from disease in a country. The results from individual animals, especially when the infection has occurred within an experimental situation, show more variation. Copyright © 2016. Published by Elsevier B.V.

  16. Evaluation of a blocking ELISA for screening of antibodies against porcine reproductive and respiratory syndrome (PRRS) virus

    DEFF Research Database (Denmark)

    Sørensen, K.J.; Bøtner, Anette; Madsen, E.S.

    1997-01-01

    A blocking Elisa was developed for the detection of antibodies against PRRS virus with a view to satisfying the need for examination of blood samples on a large scale. The test was evaluated in comparison with an indirect Elisa and the immunoperoxidase monolayer assay. The blocking Elisa...... was sensitive and specific. It had a higher capacity and was cheaper to perform than the immunoperoxidase monolayer assay and the indirect Elisa. It was comparable to the immunoperoxidase monolayer assay and better than the indirect Elisa in detecting antibodies formed early after infection, and it was superior...... to both the immunoperoxidase monolayer assay and the indirect Elisa in detecting antibodies at a late stage of infection....

  17. Sandwich enzyme-linked immunosorbent assay (ELISA) for measuring the concentration of, and detection of antibodies to, Aujeszky's disease virus.

    Science.gov (United States)

    Kardi, V; Szegletes, E; Perényi, T; Pergel, I; Smal, Z

    1990-01-01

    A double antibody sandwich enzyme-linked immunosorbent assay (ELISA) was developed for measuring Aujeszky's disease virus (ADV) antigen concentration and an inhibition technique based on the former was developed for detection of antibodies to ADV. The results were checked by determining the cytopathic and serum neutralization titres. The correlation was satisfactory in both cases, with correlation coefficients above 0.8. When measuring ADV antigen concentration, the lower limit of detection was 10(3) TCID 50/0.2 ml. The sensitivity of ELISA in detecting antibodies to ADV was found to be superior to that of the serum neutralization test and, thus, enabled the testing of rabbit and guinea-pig sera.

  18. Evaluation of classical swine fever virus antibody detection assays with an emphasis on the differentiation of infected from vaccinated animals

    DEFF Research Database (Denmark)

    Schroeder, S.; von Rosen, Tanya; Blome, S.

    2012-01-01

    vaccinated animals (DIVA). The Chekit* CSF-Sero and the HerdChek* CSFV Ab, both of which detect antibodies against the E2 protein of classical swine fever virus (CSFV), had the highest sensitivity. Both tests were practicable and showed good reproducibility. Comparable sensitivity was shown by the Chekit......The aim of this study was to evaluate the general characteristics of commercially available enzyme-linked immunosorbent assays (ELISAs) to detect antibody against classical swine fever (CSF), as well as to assess their potential use as accompanying marker tests able to differentiate infected from......* CSF-Marker, an Erns ELISA. However, this test does not allow differentiation between antibodies directed against ruminant pestiviruses and those against CSFV. Therefore, it is not suitable for use with the chimeric marker vaccines tested. The PrioCHECK® CSFV Erns was the only ELISA suitable for use...

  19. Novel antibody binding determinants on the capsid surface of serotype O foot-and-mouth disease virus

    Science.gov (United States)

    Asfor, Amin S.; Upadhyaya, Sasmita; Knowles, Nick J.; King, Donald P.; Paton, David J.

    2014-01-01

    Five neutralizing antigenic sites have been described for serotype O foot-and-mouth disease viruses (FMDV) based on monoclonal antibody (mAb) escape mutant studies. However, a mutant virus selected to escape neutralization of mAb binding at all five sites was previously shown to confer complete cross-protection with the parental virus in guinea pig challenge studies, suggesting that amino acid residues outside the mAb binding sites contribute to antibody-mediated in vivo neutralization of FMDV. Comparison of the ability of bovine antisera to neutralize a panel of serotype O FMDV identified three novel putative sites at VP2-74, VP2-191 and VP3-85, where amino acid substitutions correlated with changes in sero-reactivity. The impact of these positions was tested using site-directed mutagenesis to effect substitutions at critical amino acid residues within an infectious copy of FMDV O1 Kaufbeuren (O1K). Recovered viruses containing additional mutations at VP2-74 and VP2-191 exhibited greater resistance to neutralization with both O1K guinea pig and O BFS bovine antisera than a virus that was engineered to include only mutations at the five known antigenic sites. The changes at VP2-74 and VP3-85 are adjacent to critical amino acids that define antigenic sites 2 and 4, respectively. However VP2-191 (17 Å away from VP2-72), located at the threefold axis and more distant from previously identified antigenic sites, exhibited the most profound effect. These findings extend our knowledge of the surface features of the FMDV capsid known to elicit neutralizing antibodies, and will improve our strategies for vaccine strain selection and rational vaccine design. PMID:24584474

  20. Relationship between the prevalence of antibodies to arbovirus and hepatitis B virus in the Vale do Ribeira region, Brazil

    Directory of Open Access Journals (Sweden)

    Cláudio Sérgio Pannuti

    1989-04-01

    Full Text Available 280 students, between 6 and 14 years old, residents in the Iguape county, southern coast of the State of São Paulo, were studied in order to identify the existence of a possible association between the prevalence of specific antibodies to the hepatitis B virus and the exposure to haematophagous mosquitoes, evaluated indirectly through the prevalence of antibodies to 17 arboviruses isolated in Brazil. The children were from 4 areas with different topographical characteristics: 89 of the children were from the urban zone of the town of Iguape, 89 were from the periurban zone, 30 were from the rural area with extensive banana plantations, and 72 were from the jungle zone. Previous studies had shown significantly higher prevalence of antibodies to different arboviruses in the cultivated zone and the jungle zone, when compared to the urban and periurban zones of Iguape. The detection of antibodies to the HBV surface antigen (HBs Ag was done through the radioimmunoassay (Ausab, Abbott Laboratory. The cases considered positive were confirmed through the presence of anti-core HBV antibodies (anti-HBc-EIA Roche. A significantly higher prevalence of anti-HBV antibodies was observed in children from the jungle zone (26/72 = 36,1% when compared to those from the urban zone (5/89 = 5,6%, peri-urban (6/89 = 6,7% or from the cultivated zone (0/30 = 0%. The result suggest the existence of a common factor in the dissemination of the arboviruses and the hepatitis B virus, supporting the hypothesis that mosquitoes may play an important role in the HBV transmission in tropical forested region.

  1. Relationship between the prevalence of antibodies to arbovirus and hepatitis B virus in the Vale do Ribeira region, Brazil.

    Science.gov (United States)

    Pannuti, C S; Iversson, L B; de Mendonça, J S; Travassos da Rosa, A P; Granato, C F

    1989-01-01

    280 students, between 6 and 14 years old, residents in the Iguape county, southern coast of the State of São Paulo, were studied in order to identify the existence of a possible association between the prevalence of specific antibodies to the hepatitis B virus and the exposure to haematophagous mosquitoes, evaluated indirectly through the prevalence of antibodies to 17 arboviruses isolated in Brazil. The children were from 4 areas with different topographical characteristics: 89 of the children were from the urban zone of the town of Iguape, 89 were from the peri-urban zone, 30 were from the rural area with extensive banana plantations, and 72 were from the jungle zone. Previous studies had shown significantly higher prevalence of antibodies to different arboviruses in the cultivated zone and the jungle zone, when compared to the urban and peri-urban zones of Iguape. The detection of antibodies to the HBV surface antigen (HBs Ag) was done through the radioimmunoassay (Ausab, Abbott Laboratory). The cases considered positive were confirmed through the presence of anti-core HBV antibodies (anti-HBc-EIA Roche). A significantly higher prevalence of anti-HBV antibodies was observed in children from the jungle zone (26/72 = 36.1%) when compared to those from the urban zone (5/89 = 5.6%), peri-urban (6/89 = 6.7%) or from the cultivated zone (0/30 = 0%). The result suggest the existence of a common factor in the dissemination of the arboviruses and the hepatitis B virus, supporting the hypothesis that mosquitoes may play an important role in the HBV transmission in tropical forested region.

  2. Human antibodies that neutralize primary human immunodeficiency virus type 1 in vitro do not provide protection in an in vivo model.

    NARCIS (Netherlands)

    M. Schutten (Martin); K. Tenner-Racz; P. Racz; D.W. van Bekkum (Dirk); A.D.M.E. Osterhaus (Albert)

    1996-01-01

    textabstractRecently, conflicting data have been published about the ability of antibodies which efficiently neutralize T cell-adapted human immunodeficiency virus type 1 (HIV-1) strains to neutralize primary HIV-1 strains in vitro and in vivo. Here we present data indicating that such antibodies

  3. Risk of iatrogenic human immunodeficiency virus infection through transfusion of blood tested by inappropriately stored or expired rapid antibody assays in a Zambian hospital

    NARCIS (Netherlands)

    Consten, E. C.; van der Meer, J. T.; de Wolf, F.; Heij, H. A.; Henny, P. C.; van Lanschot, J. J.

    1997-01-01

    BACKGROUND: The purpose of this study was to estimate the risk of human immunodeficiency virus (HIV) infection via the transfusion of blood tested by inappropriately stored or expired rapid antibody assays in Zambia. STUDY DESIGN AND METHODS: Surgical patients (n = 370) were tested with antibody

  4. A heterologous prime-boost Ebola virus vaccine regimen induces durable neutralizing antibody response and prevents Ebola virus-like particle entry in mice.

    Science.gov (United States)

    Chen, Tan; Li, Dapeng; Song, Yufeng; Yang, Xi; Liu, Qingwei; Jin, Xia; Zhou, Dongming; Huang, Zhong

    2017-09-01

    Ebola virus (EBOV) is one of the most virulent pathogens known to humans. Neutralizing antibodies play a major role in the protection against EBOV infections. Thus, an EBOV vaccine capable of inducing a long-lasting neutralizing antibody response is highly desirable. We report here that a heterologous prime-boost vaccine regimen can elicit durable EBOV-neutralizing antibody response in mice. A chimpanzee serotype 7 adenovirus expressing EBOV GP (denoted AdC7-GP) was generated and used for priming. A truncated version of EBOV GP1 protein (denoted GP1t) was produced at high levels in Drosophila S2 cells and used for boosting. Mouse immunization studies showed that the AdC7-GP prime/GP1t boost vaccine regimen was more potent in eliciting neutralizing antibodies than either the AdC7-GP or GP1t alone. Neutralizing antibodies induced by the heterologous prime-boost regimen sustained at high titers for at least 18 weeks after immunization. Significantly, in vivo challenge studies revealed that the entry of reporter EBOV-like particles was efficiently blocked in mice receiving the heterologous prime-boost regimen even at 18 weeks after the final dose of immunization. These results suggest that this novel AdC7-GP prime/GP1t boost regimen represents an EBOV vaccine approach capable of establishing long-term protection, and therefore warrants further development. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Presence of virus neutralizing antibodies in cerebral spinal fluid correlates with non-lethal rabies in dogs.

    Directory of Open Access Journals (Sweden)

    Clement W Gnanadurai

    Full Text Available Rabies is traditionally considered a uniformly fatal disease after onset of clinical manifestations. However, increasing evidence indicates that non-lethal infection as well as recovery from flaccid paralysis and encephalitis occurs in laboratory animals as well as humans.Non-lethal rabies infection in dogs experimentally infected with wild type dog rabies virus (RABV, wt DRV-Mexico correlates with the presence of high level of virus neutralizing antibodies (VNA in the cerebral spinal fluid (CSF and mild immune cell accumulation in the central nervous system (CNS. By contrast, dogs that succumbed to rabies showed only little or no VNA in the serum or in the CSF and severe inflammation in the CNS. Dogs vaccinated with a rabies vaccine showed no clinical signs of rabies and survived challenge with a lethal dose of wild-type DRV. VNA was detected in the serum, but not in the CSF of immunized dogs. Thus the presence of VNA is critical for inhibiting virus spread within the CNS and eventually clearing the virus from the CNS.Non-lethal infection with wt RABV correlates with the presence of VNA in the CNS. Therefore production of VNA within the CNS or invasion of VNA from the periphery into the CNS via compromised blood-brain barrier is important for clearing the virus infection from CNS, thereby preventing an otherwise lethal rabies virus infection.

  6. Quantitative analyses reveal distinct sensitivities of the capture of HIV-1 primary viruses and pseudoviruses to broadly neutralizing antibodies.

    Science.gov (United States)

    Kim, Jiae; Jobe, Ousman; Peachman, Kristina K; Michael, Nelson L; Robb, Merlin L; Rao, Mangala; Rao, Venigalla B

    2017-08-01

    Development of vaccines capable of eliciting broadly neutralizing antibodies (bNAbs) is a key goal to controlling the global AIDS epidemic. To be effective, bNAbs must block the capture of HIV-1 to prevent viral acquisition and establishment of reservoirs. However, the role of bNAbs, particularly during initial exposure of primary viruses to host cells, has not been fully examined. Using a sensitive, quantitative, and high-throughput qRT-PCR assay, we found that primary viruses were captured by host cells and converted into a trypsin-resistant form in less than five minutes. We discovered, unexpectedly, that bNAbs did not block primary virus capture, although they inhibited the capture of pseudoviruses/IMCs and production of progeny viruses at 48h. Further, viruses escaped bNAb inhibition unless the bNAbs were present in the initial minutes of exposure of virus to host cells. These findings will have important implications for HIV-1 vaccine design and determination of vaccine efficacy. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Structure of Simian Immunodeficiency Virus Envelope Spikes Bound with CD4 and Monoclonal Antibody 36D5.

    Science.gov (United States)

    Hu, Guiqing; Liu, Jun; Roux, Kenneth H; Taylor, Kenneth A

    2017-08-15

    The human immunodeficiency virus type 1 (HIV-1)/simian immunodeficiency virus (SIV) envelope spike (Env) mediates viral entry into host cells. The V3 loop of the gp120 component of the Env trimer contributes to the coreceptor binding site and is a target for neutralizing antibodies. We used cryo-electron tomography to visualize the binding of CD4 and the V3 loop monoclonal antibody (MAb) 36D5 to gp120 of the SIV Env trimer. Our results show that 36D5 binds gp120 at the base of the V3 loop and suggest that the antibody exerts its neutralization effect by blocking the coreceptor binding site. The antibody does this without altering the dynamics of the spike motion between closed and open states when CD4 is bound. The interaction between 36D5 and SIV gp120 is similar to the interaction between some broadly neutralizing anti-V3 loop antibodies and HIV-1 gp120. Two conformations of gp120 bound with CD4 are revealed, suggesting an intrinsic dynamic nature of the liganded Env trimer. CD4 binding substantially increases the binding of 36D5 to gp120 in the intact Env trimer, consistent with CD4-induced changes in the conformation of gp120 and the antibody binding site. Binding by MAb 36D5 does not substantially alter the proportions of the two CD4-bound conformations. The position of MAb 36D5 at the V3 base changes little between conformations, indicating that the V3 base serves as a pivot point during the transition between these two states. IMPORTANCE Glycoprotein spikes on the surfaces of SIV and HIV are the sole targets available to the immune system for antibody neutralization. Spikes evade the immune system by a combination of a thick layer of polysaccharide on the surface (the glycan shield) and movement between spike domains that masks the epitope conformation. Using SIV virions whose spikes were "decorated" with the primary cellular receptor (CD4) and an antibody (36D5) at part of the coreceptor binding site, we visualized multiple conformations trapped by the

  8. Consecutive natural influenza a virus infections in sentinel mallards in the evident absence of subtype-specific hemagglutination inhibiting antibodies.

    Science.gov (United States)

    Globig, A; Fereidouni, S R; Harder, T C; Grund, C; Beer, M; Mettenleiter, T C; Starick, E

    2013-10-01

    Dabbling ducks, particularly Mallards (Anas platyrhynchos) have been frequently and consistently reported to play a pivotal role as a reservoir of low pathogenic avian influenza viruses (AIV). From October 2006 to November 2008, hand-raised Mallard ducks kept at a pond in an avifaunistically rich area of Southern Germany served as sentinel birds in the AIV surveillance programme in Germany. The pond was regularly visited by several species of dabbling ducks. A flock of sentinel birds, consisting of the same 16 individual birds during the whole study period, was regularly tested virologically and serologically for AIV infections. Swab samples were screened by RT-qPCR and, if positive, virus was isolated in embryonated chicken eggs. Serum samples were tested by the use of competitive ELISA and hemagglutinin inhibition (HI) assay. Sequences of full-length hemagglutinin (HA) and neuraminidase (NA) genes were phylogenetically analysed. Four episodes of infections with Eurasian-type AIV occurred in August (H6N8), October/November (H3N2, H2N3) 2007, in January (H3N2) and September (H3N8) 2008. The HA and NA genes of the H3N2 viruses of October 2007 and January 2008 were almost identical rendering the possibility of a re-introduction of that virus from the environment of the sentinel flock highly likely. The HA of the H3N8 virus of September 2008 belonged to a different cluster. As a correlate of the humoral immune response, titres of nucleocapsid protein-specific antibodies fluctuated in correlation with the course of AIV infection episodes. However, no specific systemic response of hemagglutination inhibiting antibodies could be demonstrated even if homologous viral antigens were used. Besides being useful as early indicators for the circulation of influenza viruses in a specific region, the sentinel ducks also contributed to gaining insights into the ecobiology of AIV infection in aquatic wild birds. © 2012 Blackwell Verlag GmbH.

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

    Science.gov (United States)

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

    2016-08-01

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

  10. 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.

    2013-01-01

    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

  11. Integration of antibody by surface functionalization of graphite-encapsulated magnetic beads using ammonia gas plasma technology for capturing influenza A virus.

    Science.gov (United States)

    Sakudo, Akikazu; Chou, Han; Ikuta, Kazuyoshi; Nagatsu, Masaaki

    2015-05-01

    Antibody-integrated magnetic beads have been functionalized for influenza A virus capture. First, ammonia plasma produced by a radio frequency power source was reacted with the surface of graphite-encapsulated magnetic beads to introduce amino groups. Anti-influenza A virus hemagglutinin antibody was then anchored by its surface sulfide groups to the amino groups on the beads via N-succinimidyl 3-(2-pyridyldithio) propionate. After incubation with influenza A virus, adsorption of the virus to the beads was confirmed by immunochromatography, polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), and inoculation of chicken embryonated eggs, indicating that virus infectivity is maintained and that the proposed method is useful for the enhanced detection and isolation of influenza A virus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Critical epitopes in the nucleocapsid protein of SFTS virus recognized by a panel of SFTS patients derived human monoclonal antibodies.

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    Li Yu

    Full Text Available BACKGROUND: SFTS virus (SFTSV is a newly discovered pathogen to cause severe fever with thrombocytopenia syndrome (SFTS in human. Successful control of SFTSV epidemic requires better understanding of the antigen target in humoral immune responses to the new bunyavirus infection. METHODOLOGY/PRINCIPAL FINDINGS: We have generated a combinatorial Fab antibody phage library from two SFTS patients recovered from SFTSV infection. To date, 94 unique human antibodies have been generated and characterized from over 1200 Fab antibody clones obtained by screening the library with SFTS purified virions. All those monoclonal antibodies (MAbs recognized the nucleocapsid (N protein of SFTSV while none of them were reactive to the viral glycoproteins Gn or Gc. Furthermore, over screening 1000 mouse monoclonal antibody clones derived from SFTSV virions immunization, 462 clones reacted with N protein, while only 16 clones were reactive to glycoprotein. Furthermore, epitope mapping of SFTSV N protein was performed through molecular simulation, site mutation and competitive ELISA, and we found that at least 4 distinct antigenic epitopes within N protein were recognized by those human and mouse MAbs, in particular mutation of Glu10 to Ala10 abolished or significantly reduced the binding activity of nearly most SFTS patients derived MAbs. CONCLUSIONS/SIGNIFICANCE: The large number of human recombinant MAbs derived from SFTS patients recognized the viral N protein indicated the important role of the N protein in humoral responses to SFTSV infection, and the critical epitopes we defined in this study provided molecular basis for detection and diagnosis of SFTSV infection.

  13. Production, purification and characterization of polyclonal antibody against the truncated gK of the duck enteritis virus

    Directory of Open Access Journals (Sweden)

    Zhang Shunchuan

    2010-09-01

    Full Text Available Abstract Duck virus enteritis (DVE is an acute, contagious herpesvirus infection of ducks, geese, and swans, which has produced significant economic losses in domestic and wild waterfowl. With the purpose of decreasing economic losses in the commercial duck industry, studying the unknown glycoprotein K (gK of DEV may be a new method for preferably preventing and curing this disease. So this is the first time to product and purify the rabbit anti-tgK polyclonal antibody. Through the western blot and ELISA assay, the truncated glycoprotein K (tgK has good antigenicity, also the antibody possesses high specificity and affinity. Meanwhile the rabbit anti-tgK polyclonal antibody has the potential to produce subunit vaccines and the functions of neutralizing DEV and anti-DEV infection because of its neutralization titer. Indirect immunofluorescent microscopy using the purified rabbit anti-tgK polyclonal antibody as diagnostic antibody was susceptive to detect a small quantity of antigen in tissues or cells. This approach also provides effective experimental technology for epidemiological investigation and retrospective diagnose of the preservative paraffin blocks.

  14. Antibodies to parvovirus, distemper virus and adenovirus conferred to household dogs using commercial combination vaccines containing Leptospira bacterin.

    Science.gov (United States)

    Taguchi, M; Namikawa, K; Maruo, T; Lynch, J; Sahara, H

    2010-12-11

    To examine how the inclusion (+) or exclusion (-) of inactivated Leptospira antigens in a vaccine for canine parvovirus type 2 (CPV-2), canine distemper virus (CDV) and canine adenovirus type 2 (CAdV-2) affects antibody titres to CPV-2, CDV and CAdV-1 antigens, household dogs were vaccinated with commercially available vaccines from one of three manufacturers. CPV-2, CDV and CAdV-1 antibody titres were measured 11 to 13 months later and compared within three different age groups and three different bodyweight groups. There were significant differences between CPV-2 antibody titres in dogs vaccinated with (+) vaccine and those vaccinated with (-) vaccine for two products in the two-year-old group and for one product in the greater than seven-year-old group; no significant differences were seen that could be attributed to bodyweight. No differences in CDV antibody titres were observed within age groups, but a significant difference was seen in the 11 to 20 kg weight group for one product. Significant differences in CAdV-1 antibody titres were seen for one product in both the two-year-old group and the ≤10 kg weight group.

  15. Determining the feline immunodeficiency virus (FIV) status of FIV-vaccinated cats using point-of-care antibody kits.

    Science.gov (United States)

    Westman, Mark E; Malik, Richard; Hall, Evelyn; Sheehy, Paul A; Norris, Jacqueline M

    2015-10-01

    This study challenges the commonly held view that the feline immunodeficiency virus (FIV) infection status of FIV-vaccinated cats cannot be determined using point-of-care antibody test kits due to indistinguishable antibody production in FIV-vaccinated and naturally FIV-infected cats. The performance of three commercially available point-of-care antibody test kits was compared in a mixed population of FIV-vaccinated (n=119) and FIV-unvaccinated (n=239) cats in Australia. FIV infection status was assigned by considering the results of all antibody kits in concert with results from a commercially available PCR assay (FIV RealPCR™). Two lateral flow immunochromatography test kits (Witness FeLV/FIV; Anigen Rapid FIV/FeLV) had excellent overall sensitivity (100%; 100%) and specificity (98%; 100%) and could discern the true FIV infection status of cats, irrespective of FIV vaccination history. The lateral flow ELISA test kit (SNAP FIV/FeLV Combo) could not determine if antibodies detected were due to previous FIV vaccination, natural FIV infection, or both. The sensitivity and specificity of FIV RealPCR™ for detection of viral and proviral nucleic acid was 92% and 99%, respectively. These results will potentially change the way veterinary practitioners screen for FIV in jurisdictions where FIV vaccination is practiced, especially in shelter scenarios where the feasibility of mass screening is impacted by the cost of testing. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Generation, characterization and epitope mapping of two neutralizing and protective human recombinant antibodies against influenza A H5N1 viruses.

    Directory of Open Access Journals (Sweden)

    Lina Sun

    Full Text Available BACKGROUND: The development of new therapeutic targets and strategies to control highly pathogenic avian influenza (HPAI H5N1 virus infection in humans is urgently needed. Broadly cross-neutralizing recombinant human antibodies obtained from the survivors of H5N1 avian influenza provide an important role in immunotherapy for human H5N1 virus infection and definition of the critical epitopes for vaccine development. METHODOLOGY/PRINCIPAL FINDINGS: We have characterized two recombinant baculovirus-expressed human antibodies (rhAbs, AVFluIgG01 and AVFluIgG03, generated by screening a Fab antibody phage library derived from a patient recovered from infection with a highly pathogenic avian influenza A H5N1 clade 2.3 virus. AVFluIgG01 cross-neutralized the most of clade 0, clade 1, and clade 2 viruses tested, in contrast, AVFluIgG03 only neutralized clade 2 viruses. Passive immunization of mice with either AVFluIgG01 or AVFluIgG03 antibody resulted in protection from a lethal H5N1 clade 2.3 virus infection. Furthermore, through epitope mapping, we identify two distinct epitopes on H5 HA molecule recognized by these rhAbs and demonstrate their potential to protect against a lethal H5N1 virus infection in a mouse model. CONCLUSIONS/SIGNIFICANCE: Importantly, localization of the epitopes recognized by these two neutralizing and protective antibodies has provided, for the first time, insight into the human antibody responses to H5N1 viruses which contribute to the H5 immunity in the recovered patient. These results highlight the potential of a rhAbs treatment strategy for human H5N1 virus infection and provide new insight for the development of effective H5N1 pandemic vaccines.

  17. Prevalence of protective antibody titers for canine distemper virus and canine parvovirus in dogs entering a Florida animal shelter.

    Science.gov (United States)

    Lechner, Elizabeth S; Crawford, P Cynda; Levy, Julie K; Edinboro, Charlotte H; Dubovi, Edward J; Caligiuri, Randy

    2010-06-15

    To determine the proportion of dogs entering an animal shelter with protective antibody titers (PATs) for canine distemper virus (CDV) and canine parvovirus (CPV) and identify factors associated with having a PAT. Cross-sectional study. 431 dogs admitted to an open-admission municipal animal shelter in north central Florida with a history of infectious disease outbreaks. Blood was collected from dogs on the day of admission to the shelter. Antibody titers for CDV and CPV were measured by virus neutralization and hemagglutination inhibition, respectively. Age, sex, neuter status, address of origin, source (stray or previously owned), health status (healthy or not healthy), and outcome (adoption, euthanasia, or reclaimed by owner) data were also collected. Overall, 64.5% (278/431) of dogs had insufficient titers for antibodies against CDV, CPV, or both. A total of 153 (35.5%) dogs had PATs for both CDV and CPV, 33 (7.7%) had PATs for CDV but not CPV, 136 (31.5%) had PATs for CPV but not CDV, and 109 (25.3%) did not have PATs for either virus. Older dogs were more likely to have PATs for CDV and CPV. Neutered dogs were more likely to have PATs for CDV. Factors not associated with having a PAT included source, health status, and type of community from which the dog originated. Most dogs had insufficient antibody titers for CDV, CPV, or both at the time of admission to the animal shelter. Findings support current guidelines recommending vaccination of all dogs immediately upon admission to shelters, regardless of source or physical condition.

  18. Comparison of Epstein Barr Virus Antibodies And Tcell Cytokines Production in Patients With Multiple Sclerosis and Healthy Individuals

    Directory of Open Access Journals (Sweden)

    Amir Hassan Zarnani

    2010-11-01

    Full Text Available Background:Multiple sclerosis(MS is the most common autoimmune disease of central nervous system with destruction of myelin sheath mediated by auto reactive CD4+ T Lymphocytes. Because of the possible role of Epstein-Barr virus in etiology of MS and T cells immune response, the aim of this study was to evaluate anti-Epstein Barr virus antibodies as a marker of reactivity and production of TH1 and TH2 cytokines in MS patients and healthy individuals.   Methods: Blood samples were taken from 68 MS patients at different stages of diseases and 20 apparently healthy individuals and plasma levels of anti- EBV nuclear antigen-1 (EBNA-1 and viral capsid antigen (VCA antibodies determined and concentrations of IFN- [1] , IL-12 and IL-4 in culture supernatants of PHA-activated peripheral blood mononuclear cells (PBMC were measured by ELISA.   Results: The mean levels of anti EBNA-1 and VCAantibodies were significantly higher in patients compared to controls (p=0.04, p=0.001 respectively. Concentrations of IFN- [1] , IL-4 & IL-12 were also significantly higher in MS patients than healthy individuals (p=0.001, p=0.005, p=0.002, respectively. Significant correlation was found between anti EBNA-1 and VCAantibodies and IL-12 production (p =0.02, r=0.27& p=0.04, r=0.25, respectively; whereas no significant correlation was found between these antibodies and production of IFN- [1] or IL-4.   Conclusions: Due to elevated level of anti-EBV antibodies and T cell Cytokines in MS patients Rather than healthy individuals, Epstein Barr virus may play role in etiology of MS disease through activation of T cells immune response.

  19. A comparative antibody study of the potential susceptibility of Thoroughbred and non?Thoroughbred horse populations in Ireland to equine influenza virus

    OpenAIRE

    Gildea, Sarah; Arkins, Sean; Cullinane, Ann

    2010-01-01

    Please cite this paper as: Gildea et?al. (2010) A comparative antibody study of the potential susceptibility of Thoroughbred and non?Thoroughbred horse populations in Ireland to equine influenza virus. Influenza and Other Respiratory Viruses 4(6), 363?372. Background? In Ireland, horses may be protected against equine influenza virus (EIV) as a result of natural exposure or vaccination. Current mandatory vaccination programmes are targeted at highly mobile horses. A correlation between antibo...

  20. The Role of the Hendra Virus and Nipah Virus Attachment Glycoproteins in Receptor Binding and Antibody Neutralization

    Science.gov (United States)

    2014-01-31

    of important human (measles (MeV), mumps, human parainfluenza and respiratory syncytial virus (RSV)) and animal ( canine distemper virus (CDV...occurrence of a natural canine infection (6; 7). Since the emergence of HeV there have been a total of 86 horse fatalities, 2 canine infections and 7...Infectious Diseases 6. Anonymous. 2011. HENDRA VIRUS, EQUINE - AUSTRALIA (21): (QUEENSLAND) CANINE . Pro-Med-mail, Archive No. 20110802.2324

  1. Prevalence of antibodies against Kilham virus in experimental rat colonies of Argentina Prevalencia de anticuerpos contra el virus Kilham en colonias experimentales de ratas de Argentina

    Directory of Open Access Journals (Sweden)

    M. P. Cagliada

    2010-02-01

    Full Text Available The Kilham rat virus (KRV is a parvovirus originally isolated from a rat sarcoma in the late 1950s. The clinical signs associated with a natural KRV infection include foetal resorption in dams, runtin, ataxia, cerebellar hypoplasia and jaundice in suckling rats, and sudden death, scrotal cyanosis, abdominal swelling and dehydration in juvenile rats. The ability of this virus to produce persistent infections has resulted in a high frequency of contamination of cell cultures and transplantable-tumor system. In addition, the virus may interfere with research in other ways. The remarkable resistance to environmental conditions determines the importance of the detection and control of this agent, especially in the laboratory animal production. This study determines the seroprevalence of Kilham antibodies from sera of adult rats from conventional facilities, using the haemagglutination inhibition test. The seroprevalence varied between 27.8% and 75%. This result confirms that the virus is circulating in Argentinean conventional facilities and might be interfering with research. The recognized Kilham virus may be prevented from supply sources by implementing a health monitoring schedule including a regular serological surveillance, and by keeping the animals under barrier systems.El virus Kilham es un parvovirus aislado originalmente a partir de un sarcoma de rata, a fines de la década del 50. Los signos clínicos que produce son reabsorción fetal, disminución del crecimiento, ataxia, hipoplasia cerebelar, ictericia en lactantes, muerte súbita, cianosis escrotal, hinchazón abdominal y deshidratación de ratas jóvenes. La capacidad del virus para producir infecciones persistentes hace que los cultivos celulares derivados de ratas puedan estar contaminados. Además, el virus puede interferir con los ensayos de investigación de diferentes formas. La resistencia a las condiciones ambientales determina la importancia de la detección y el control de

  2. Neutralizing antibodies induced by recombinant virus-like particles of enterovirus 71 genotype C4 inhibit infection at pre- and post-attachment steps.

    Directory of Open Access Journals (Sweden)

    Zhiqiang Ku

    Full Text Available BACKGROUND: Enterovirus 71 (EV71 is a major causative agent of hand, foot and mouth disease, which has been prevalent in Asia-Pacific regions, causing significant morbidity and mortality in young children. Antibodies elicited by experimental EV71 vaccines could neutralize infection in vitro and passively protect animal models from lethal challenge, indicating that neutralizing antibodies play an essential role in protection. However, how neutralizing antibodies inhibit infection in vitro remains unclear. METHODS/FINDINGS: In the present study, we explored the mechanisms of neutralization by antibodies against EV71 virus-like particles (VLPs. Recombinant VLPs of EV71 genotype C4 were produced in insect cells using baculovirus vectors. Immunization with the VLPs elicited a high-titer, EV71-specific antibody response in mice. Anti-VLP mouse sera potently neutralized EV71 infection in vitro. The neutralizing antibodies in the anti-VLP mouse sera were found to target mainly an extremely conserved epitope (FGEHKQEKDLEYGAC located at the GH loop of the VP1 protein. The neutralizing anti-VLP antisera were able to inhibit virus binding to target cells efficiently. In addition, post-attachment treatment of virus-bound cells with the anti-VLP antisera also neutralized virus infection, although the antibody concentration required was higher than that of the pre-attachment treatment. CONCLUSIONS: Collectively, our findings represent a valuable addition to the understanding of mechanisms of EV71 neutralization and have strong implications for EV71 vaccine development.

  3. Influenza A virus infection engenders a poor antibody response against the ectodomain of matrix protein 2

    Directory of Open Access Journals (Sweden)

    Wunner William

    2006-12-01

    Full Text Available Abstract Background Matrix protein 2 (M2 is an integral tetrameric membrane protein of influenza A virus (IAV. Its ectodomain (M2e shows remarkably little diversity amongst human IAV strains. As M2e-specific antibodies (Abs have been shown to reduce the severity of infection in animals, M2e is being studied for its capability of providing protection against a broad range of IAV strains. Presently, there is little information about the concentration of M2e-specific Abs in humans. Two previous studies made use of ELISA and Western blot against M2e peptides and recombinant M2 protein as immunosorbents, respectively, and reported Ab titers to be low or undetectable. An important caveat is that these assays may not have detected all Abs capable of binding to native tetrameric M2e. Therefore, we developed an assay likely to detect all M2e tetramer-specific Abs. Results We generated a HeLa cell line that expressed full length tetrameric M2 (HeLa-M2 or empty vector (HeLa-C10 under the control of the tetracycline response element. These cell lines were then used in parallel as immunosorbents in ELISA. The assay was standardized and M2e-specific Ab titers quantified by means of purified murine or chimeric (mouse variable regions, human constant regions M2e-specific Abs in the analysis of mouse and human sera, respectively. We found that the cell-based ELISA was substantially more effective than immobilized M2e peptide in detecting M2e-specific Abs in sera of mice that had recovered from repetitive IAV infections. Still, titers remained low ( Conclusion The results provide convincing evidence that M2e-specific Ab-mediated protection is currently lacking or suboptimal in humans.

  4. Prognostic value of anti-Epstein-Barr virus antibodies in nasopharyngeal carcinoma (NPC)

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Mu-Tai; Yeh, Chi-Yuan [Chang-Hua Christian Hospital, Chang-Hua (Taiwan, Province of China)

    1998-03-01

    Eighty patients with histological diagnoses of nasopharyngeal cancer (NPC) were referred to Chang-Hua Christian Hospital for curative radiotherapy from 1985 to 1995. A mean dose of 7,020 cGy in 39 fractions was delivered to the primary tumor using a telecobalt-60 unit or 6-10 MV X-ray linear accelerator. Pre- and postradiotherapy serum levels of anti-Epstein-Barr virus (EBV)/VCA IgG and IgA were determined for all patients using the indirect immunoperoxidase assay. Multivariate analysis was done to determine which factors affected the patients` treatment outcome and survival. Five patients were excluded from this study due to incomplete radiotherapy, leaving 75 patients eligible for analysis. Overall local control was 77.3%, with a mean disease-free interval of 19.7 months. Factors affecting local control included radiation dose and pretreatment anti-EBV/VCA IgG titer. The overall 5-year actuarial survival for the 75 patients was 75%, with a median survival of 129.5 months. The 5-year actuarial survival rates for stage I+II, III, and IV patients were 90%, 40%, and 45%, respectively. Prognostic factors for survival included tumor histological type and pretreatment anti-EBV/VCA IgA titer, while prognostic factors for local control included total radiation dose received and pretreatment anti-EBV/VCA IgG titer. We found that there was a significant difference in the geometric mean titer of anti-EBV/VCA IgA antibodies before and after radiotherapy. Prognostic factors affecting NPC patients` actuarial survival included tumor histology and pretreatment IgA titer, while prognostic factors for local control of NPC included total radiation dose received and pretreatment IgG titer. (K.H.)

  5. Efficacy comparative of different laboratory test reagents for hepatitis C virus antibody

    Directory of Open Access Journals (Sweden)

    GUO Feibo

    2016-09-01

    Full Text Available Objective To investigate the effects of different laboratory test reagents for hepatitis C virus (HCV antibody through a comparative analysis. Methods A total of 207 samples which tested positive by four anti-HCV screening reagents commonly used in the laboratories in China (Kehua, Xinchuang, Wantai, and Abbott were included. HCV RNA nucleic acid amplification (NAT was performed, and if NAT results were negative, recombinant immunoblot assay (RIBA was performed for further confirmation. The test results of these four screening reagents were compared, and their S/CO values and true positive rates were analyzed. Results Of all the 205 samples testing positive by any one reagent, 191 (93.2% tested positive by the four reagents, and 14 (6.8% were tested inconsistently by the four reagents. The positive predictive values of Xinchuang, Kehua, Wantai, and Abbott reagents were 88.2% (180/204, 93.8% (180/192, 91.4% (180/197, and 90.0% (180/200, respectively. The S/CO thresholds with a positive predictive value of ≥95% for Xinchuang, Kehua, Wantai, and Abbott reagents were 9.0, 4.0, 5.0, and 7.0, respectively. Conclusion Xinchuang, Kehua, Wantai, and Abbott reagents have significantly different S/CO thresholds with a positive predictive value of ≥95%, which are significantly different from those in other domestic laboratories. Each laboratory should establish an applicable S/CO threshold with a positive predictive value of ≥95%, in order to reduce the sample size for confirmatory test.

  6. Prognostic value of anti-Epstein-Barr virus antibodies in nasopharyngeal carcinoma (NPC)

    International Nuclear Information System (INIS)

    Liu, Mu-Tai; Yeh, Chi-Yuan

    1998-01-01

    Eighty patients with histological diagnoses of nasopharyngeal cancer (NPC) were referred to Chang-Hua Christian Hospital for curative radiotherapy from 1985 to 1995. A mean dose of 7,020 cGy in 39 fractions was delivered to the primary tumor using a telecobalt-60 unit or 6-10 MV X-ray linear accelerator. Pre- and postradiotherapy serum levels of anti-Epstein-Barr virus (EBV)/VCA IgG and IgA were determined for all patients using the indirect immunoperoxidase assay. Multivariate analysis was done to determine which factors affected the patients' treatment outcome and survival. Five patients were excluded from this study due to incomplete radiotherapy, leaving 75 patients eligible for analysis. Overall local control was 77.3%, with a mean disease-free interval of 19.7 months. Factors affecting local control included radiation dose and pretreatment anti-EBV/VCA IgG titer. The overall 5-year actuarial survival for the 75 patients was 75%, with a median survival of 129.5 months. The 5-year actuarial survival rates for stage I+II, III, and IV patients were 90%, 40%, and 45%, respectively. Prognostic factors for survival included tumor histological type and pretreatment anti-EBV/VCA IgA titer, while prognostic factors for local control included total radiation dose received and pretreatment anti-EBV/VCA IgG titer. We found that there was a significant difference in the geometric mean titer of anti-EBV/VCA IgA antibodies before and after radiotherapy. Prognostic factors affecting NPC patients' actuarial survival included tumor histology and pretreatment IgA titer, while prognostic factors for local control of NPC included total radiation dose received and pretreatment IgG titer. (K.H.)

  7. The HIV-1 V3 domain on field isolates: participation in generation of escape virus in vivo and accessibility to neutralizing antibodies

    DEFF Research Database (Denmark)

    Arendrup, M; Akerblom, L; Heegaard, P M

    1995-01-01

    The V3 domain is highly variable and induces HIV neutralizing antibodies (NA). Here we addressed the issues of 1) the participation of mutations in V3 in generation of neutralization resistant escape virus in vivo and 2) the applicability of synthetic V3 peptides corresponding to field isolates...... to induce neutralizing immune sera. Seven peptides corresponding to the V3 region of primary and escape virus from 3 HIV-1 infected patients were synthesized and used for antibody (Abs) studies and immunizations. The anti-V3 Abs titre in patient serum was generally low against peptides corresponding...... to autologous virus isolated later than the serum sample in contrast to the titre against peptides corresponding to virus isolated earlier than the serum sample. Furthermore, neutralizing anti-V3 monoclonal antibodies (MAbs) raised against V3 peptides from laboratory strains of HIV-1 showed distinct binding...

  8. Dengue virus specific IgY provides protection following lethal dengue virus challenge and is neutralizing in the absence of inducing antibody dependent enhancement.

    Directory of Open Access Journals (Sweden)

    Ashley L Fink

    2017-07-01

    Full Text Available Dengue hemorrhagic fever (DHF and dengue shock syndrome (DSS are severe disease manifestations that can occur following sequential infection with different dengue virus serotypes (DENV1-4. At present, there are no licensed therapies to treat DENV-induced disease. DHF and DSS are thought to be mediated by serotype cross-reactive antibodies that facilitate antibody-dependent enhancement (ADE by binding to viral antigens and then Fcγ receptors (FcγR on target myeloid cells. Using genetically engineered DENV-specific antibodies, it has been shown that the interaction between the Fc portion of serotype cross-reactive antibodies and FcγR is required to induce ADE. Additionally, it was demonstrated that these antibodies were as neutralizing as their non-modified variants, were incapable of inducing ADE, and were therapeutic following a lethal, antibody-enhanced infection. Therefore, we hypothesized that avian IgY, which do not interact with mammalian FcγR, would provide a novel therapy for DENV-induced disease. We demonstrate here that goose-derived anti-DENV2 IgY neutralized DENV2 and did not induce ADE in vitro. Anti-DENV2 IgY was also protective in vivo when administered 24 hours following a lethal DENV2 infection. We were also able to demonstrate via epitope mapping that both full-length and alternatively spliced anti-DENV2 IgY recognized different epitopes, including epitopes that have not been previously identified. These observations provide evidence for the potential therapeutic applications of goose-derived anti-DENV2 IgY.

  9. Gene Delivery of Activated Factor VII Using Alternative Adeno-Associated Virus Serotype Improves Hemostasis in Hemophiliac Mice with FVIII Inhibitors and Adeno-Associated Virus Neutralizing Antibodies.

    Science.gov (United States)

    Sun, Junjiang; Hua, Baolai; Chen, Xiaojing; Samulski, Richard J; Li, Chengwen

    2017-08-01

    While therapeutic expression of coagulation factors from adeno-associated virus (AAV) vectors has been successfully achieved in patients with hemophilia, neutralizing antibodies to the vector and inhibitory antibodies to the transgene severely limit efficacy. Indeed, approximately 40% of mice transduced with human factor VIII using the AAV8 serotype developed inhibitory antibodies to factor VIII (FVIII inhibitor), as well as extremely high titers (≥1:500) of neutralizing antibodies to AAV8. To correct hemophilia in these mice, AAV9, a serotype with low in vitro cross-reactivity (≤1:5) to anti-AAV8, was used to deliver mouse-activated factor VII (mFVIIa). It was found that within 6 weeks of systemic administration of 2 × 10 13 particles/kg of AAV9/mFVIIa, hemophiliac mice with FVIII inhibitors and neutralizing antibodies (NAb) to AAV8 achieved hemostasis comparable to that in wild-type mice, as measured by rotational thromboelastometry. A level of 737 ng/mL mFVIIa was achieved after AAV9/mFVIIa adminstration compared to around 150 ng/mL without vector treatment, and concomitantly prothrombin time was shortened. Tissues collected after intra-articular hemorrhage from FVIII-deficient mice and mice with FVIII inhibitors were scored 4.7 and 5.5, respectively, on a scale of 0-10, indicating significant pathological damage. However, transduction with AAV9/mFVIIa decreased pathology scores to 3.6 and eliminated hemosiderin iron deposition in the synovium in most mice. Collectively, these results suggest that application of alternative serotypes of AAV vector to deliver bypassing reagents has the potential to correct hemophilia and prevent hemoarthrosis, even in the presence of FVIII inhibitor and neutralizing antibodies to AAV.

  10. Dengue virus specific IgY provides protection following lethal dengue virus challenge and is neutralizing in the absence of inducing antibody dependent enhancement.

    Science.gov (United States)

    Fink, Ashley L; Williams, Katherine L; Harris, Eva; Alvine, Travis D; Henderson, Thomas; Schiltz, James; Nilles, Matthew L; Bradley, David S

    2017-07-01

    Dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) are severe disease manifestations that can occur following sequential infection with different dengue virus serotypes (DENV1-4). At present, there are no licensed therapies to treat DENV-induced disease. DHF and DSS are thought to be mediated by serotype cross-reactive antibodies that facilitate antibody-dependent enhancement (ADE) by binding to viral antigens and then Fcγ receptors (FcγR) on target myeloid cells. Using genetically engineered DENV-specific antibodies, it has been shown that the interaction between the Fc portion of serotype cross-reactive antibodies and FcγR is required to induce ADE. Additionally, it was demonstrated that these antibodies were as neutralizing as their non-modified variants, were incapable of inducing ADE, and were therapeutic following a lethal, antibody-enhanced infection. Therefore, we hypothesized that avian IgY, which do not interact with mammalian FcγR, would provide a novel therapy for DENV-induced disease. We demonstrate here that goose-derived anti-DENV2 IgY neutralized DENV2 and did not induce ADE in vitro. Anti-DENV2 IgY was also protective in vivo when administered 24 hours following a lethal DENV2 infection. We were also able to demonstrate via epitope mapping that both full-length and alternatively spliced anti-DENV2 IgY recognized different epitopes, including epitopes that have not been previously identified. These observations provide evidence for the potential therapeutic applications of goose-derived anti-DENV2 IgY.

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

    Directory of Open Access Journals (Sweden)

    Raiees Andrabi

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

  12. Development of a virus neutralisation test to detect antibodies against Schmallenberg virus and serological results in suspect and infected herds

    NARCIS (Netherlands)

    Loeffen, W.L.A.; Quak, J.; Boer-Luijtze, de E.A.; Hulst, M.M.; Poel, van der W.H.M.; Bouwstra, R.J.; Maas, H.A.

    2012-01-01

    Background: At the end of 2011, a new orthobunyavirus, tentatively named Schmallenberg virus (SBV), was discovered in Germany. This virus has since been associated with clinical signs of decreased milk production, watery diarrhoea and fever in dairy cows, and subsequently also with congenital

  13. Hepatitis C Virus E1 and E2 Proteins Used as Separate Immunogens Induce Neutralizing Antibodies with Additive Properties.

    Directory of Open Access Journals (Sweden)

    Elodie Beaumont

    Full Text Available Various strategies involving the use of hepatitis C virus (HCV E1 and E2 envelope glycoproteins as immunogens have been developed for prophylactic vaccination against HCV. However, the ideal mode of processing and presenting these immunogens for effective vaccination has yet to be determined. We used our recently described vaccine candidate based on full-length HCV E1 or E2 glycoproteins fused to the heterologous hepatitis B virus S envelope protein to compare the use of the E1 and E2 proteins as separate immunogens with their use as the E1E2 heterodimer, in terms of immunogenetic potential and the capacity to induce neutralizing antibodies. The specific anti-E1 and anti-E2 antibody responses induced in animals immunized with vaccine particles harboring the heterodimer were profoundly impaired with respect to those in animals immunized with particles harboring E1 and E2 separately. Moreover, the anti-E1 and anti-E2 antibodies had additive neutralizing properties that increase the cross-neutralization of heterologous strains of various HCV genotypes, highlighting the importance of including both E1 and E2 in the vaccine for an effective vaccination strategy. Our study has important implications for the optimization of HCV vaccination strategies based on HCV envelope proteins, regardless of the platform used to present these proteins to the immune system.

  14. Rapid Transient Production of a Monoclonal Antibody Neutralizing the Porcine Epidemic Diarrhea Virus (PEDV) in Nicotiana benthamiana and Lactuca sativa.

    Science.gov (United States)

    Rattanapisit, Kaewta; Srijangwad, Anchalee; Chuanasa, Taksina; Sukrong, Suchada; Tantituvanont, Angkana; Mason, Hugh S; Nilubol, Dachrit; Phoolcharoen, Waranyoo

    2017-12-01

    Porcine epidemic diarrhea virus (PEDV) causes acute diarrhea, vomiting, dehydration, weight loss, and high mortality rate in neonatal piglets. Porcine epidemic diarrhea (PED) has been reported in Europe, America, and Asia including Thailand. The disease causes substantial losses to the swine industry in many countries. Presently, there is no effective PEDV vaccine available. In this study, we developed a plant-produced monoclonal antibody (mAb) 2C10 as a prophylactic candidate to prevent the PEDV infection. Recently, plant expression systems have gained interest as an alternative for the production of antibodies because of many advantages, such as low production cost, lack of human and animal pathogen, large scalability, etc. The 2C10 mAb was transiently expressed in Nicotiana benthamiana and lettuce using geminiviral vector. After purification by protein A affinity chromatography, the antibody was tested for the binding and neutralizing activity against PEDV. Our result showed that the plant produced 2C10 mAb can bind to the virus and also inhibit PEDV infection in vitro . These results show excellent potential for a plant-expressed 2C10 as a PEDV prophylaxis and a diagnostic for PEDV infection. Georg Thieme Verlag KG Stuttgart · New York.

  15. IL-15 enhances cross-reactive antibody recall responses to seasonal H3 influenza viruses in vitro [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Junqiong Huang

    2017-11-01

    Full Text Available Background: Recently, several human monoclonal antibodies that target conserved epitopes on the stalk region of influenza hemagglutinin (HA have shown broad reactivity to influenza A subtypes. Also, vaccination with recombinant chimeric HA or stem fragments from H3 influenza viruses induce broad immune protection in mice and humans. However, it is unclear whether stalk-binding antibodies can be induced in human memory B cells by seasonal H3N2 viruses. Methods: In this study, we recruited 13 donors previously exposed to H3 viruses, the majority (12 of 13 of which had been immunized with seasonal influenza vaccines. We evaluated plasma baseline strain-specific and stalk-reactive anti-HA antibodies and B cell recall responses to inactivated H3N2 A/Victoria/361/2011 virus in vitro using a high throughput multiplex (mPlex-Flu assay. Results: Stalk-reactive IgG was detected in the plasma of 7 of the subjects. Inactivated H3 viral particles rapidly induced clade cross-reactive antibodies in B cell cultures derived from all 13 donors. In addition, H3 stalk-reactive antibodies were detected in culture supernatants from 7 of the 13 donors (53.8%.  H3 stalk-reactive antibodies were also induced by H1 and H7 subtypes. Interestingly, broadly cross-reactive antibody recall responses to H3 strains were also enhanced by stimulating B cells in vitro with CpG2006 ODN in the presence of IL-15. H3 stalk-reactive antibodies were detected in  CpG2006 ODN + IL-15 stimulated B cell cultures derived from 12 of the 13 donors (92.3%, with high levels detected in cultures from 7 of the 13 donors. Conclusions: Our results demonstrate that stalk-reactive antibody recall responses induced by seasonal H3 viruses and CpG2006 ODN can be enhanced by IL-15.

  16. From hybridomas to a robust microalgal-based production platform: molecular design of a diatom secreting monoclonal antibodies directed against the Marburg virus nucleoprotein.

    Science.gov (United States)

    Hempel, Franziska; Maurer, Michael; Brockmann, Björn; Mayer, Christian; Biedenkopf, Nadine; Kelterbaum, Anne; Becker, Stephan; Maier, Uwe G

    2017-07-27

    The ideal protein expression system should provide recombinant proteins in high quality and quantity involving low production costs only. However, especially for complex therapeutic proteins like monoclonal antibodies many challenges remain to meet this goal and up to now production of monoclonal antibodies is very costly and delicate. Particularly, emerging disease outbreaks like Ebola virus in Western Africa in 2014-2016 make it necessary to reevaluate existing production platforms and develop robust and cheap alternatives that are easy to handle. In this study, we engineered the microalga Phaeodactylum tricornutum to produce monoclonal IgG antibodies against the nucleoprotein of Marburg virus, a close relative of Ebola virus causing severe hemorrhagic fever with high fatality rates in humans. Sequences for both chains of a mouse IgG antibody were retrieved from a murine hybridoma cell line and implemented in the microalgal system. Fully assembled antibodies were shown to be secreted by the alga and antibodies were proven to be functional in western blot, ELISA as well as IFA studies just like the original hybridoma produced IgG. Furthermore, synthetic variants with constant regions of a rabbit IgG and human IgG with optimized codon usage were produced and characterized. This study highlights the potential of microalgae as robust and low cost expression platform for monoclonal antibodies secreting IgG antibodies directly into the culture medium. Microalgae possess rapid growth rates, need basically only water, air and sunlight for cultivation and are very easy to handle.

  17. 9 CFR 113.47 - Detection of extraneous viruses by the fluorescent antibody technique.

    Science.gov (United States)

    2010-01-01

    ... respiratory syncytial virus. (3) Canine cells shall, in addition, be tested for: (i) Canine coronavirus; (ii) Canine distemper virus; and (iii) Canine parvovirus. (4) Equine cells shall, in addition, be tested for...

  18. Indication of viruses and virus-specific antibodies by ELISA using conjugates based on β-lactamase obtained by genetic engineering

    International Nuclear Information System (INIS)

    Kharitonenkov, I.G.; Kordym, V.A.; Khristova, M.L.; Leonov, S.V.; Kirillova, V.S.; Chernykh, S.I.

    1987-01-01

    The method of enzyme-linked immunosorbent assay (ELISA), by means of which antigens and antibodies of different origin can be detected with high sensitivity and specificity, is an immunoenzymatic technique based on the use of conjugates, or macromolecular complexes formed by covalent attachment of enzyme molecules to antigen or antibody molecules. Conjugates based on peroxidase, alkaline phosphatase, and beta-galactosidase are most frequently used to construct immunoenzymatic test systems. The use of these enzymes in ELISA, however, is complicated by the fact that they are often present in free or bound form in the biological material under study, and that their substrates either possess low stability, are difficult to synthesize, or are toxic. In this paper, in order to avoid these shortcomings, the authors develop a method for the biosynthesis of lactamase conjugates which is based on genetic engineering, and demonstrate the viability and stability of these conjugates in radioimmunoenzymatic assay of viruses

  19. Survey for antibodies to infectious bursal disease virus serotype 2 in wild turkeys and Sandhill Cranes of Florida, USA.

    Science.gov (United States)

    Candelora, Kristen L; Spalding, Marilyn G; Sellers, Holly S

    2010-07-01

    Captive-reared Whooping Cranes (Grus americana) released into Florida for the resident reintroduction project experienced unusually high mortality and morbidity during the 1997-98 and 2001-02 release seasons. Exposure to infectious bursal disease virus (IBDV) serotype 2 as evidenced by seroconversion was suspected to be the factor that precipitated these mortality events. Very little is known about the incidence of IBD in wild bird populations. Before this study, natural exposure had not been documented in wild birds of North America having no contact with captive-reared cranes, and the prevalence and transmission mechanisms of the virus in wild birds were unknown. Sentinel chickens (Gallus gallus) monitored on two Whooping Crane release sites in central Florida, USA, during the 2003-04 and 2004-05 release seasons seroconverted, demonstrating natural exposure to IBDV serotype 2. Blood samples collected from Wild Turkeys (Meleagris gallopavo) and Sandhill Cranes (Grus canadensis) in eight of 21 counties in Florida, USA, and one of two counties in southern Georgia, USA, were antibody-positive for IBDV serotype 2, indicating that exposure from wild birds sharing habitat with Whooping Cranes is possible. The presence of this virus in wild birds in these areas is a concern for the resident flock of Whooping Cranes because they nest and raise their chicks in Florida, USA. However, passively transferred antibodies may protect them at this otherwise vulnerable period in their lives.

  20. Seroprevalence of antibodies against highly pathogenic avian influenza A (H5N1 virus among poultry workers in Bangladesh, 2009.

    Directory of Open Access Journals (Sweden)

    Sharifa Nasreen

    Full Text Available We conducted a cross-sectional study in 2009 to determine the seroprevalence and risk factors for highly pathogenic avian influenza A (H5N1 [HPAI H5N1] virus antibodies among poultry workers at farms and live bird markets with confirmed/suspected poultry outbreaks during 2009 in Bangladesh. We tested sera by microneutralization assay using A/Bangladesh/207095/2008 (H5N1; clade 2.2.2 virus with confirmation by horse red blood cell hemagglutination inhibition and H5-specific Western blot assays. We enrolled 212 workers from 87 farms and 210 workers from three live bird markets. One hundred and two farm workers (48% culled poultry. One hundred and ninety-three farm workers (91% and 178 market workers (85% reported direct contact with poultry that died during a laboratory confirmed HPAI H5N1 poultry farm outbreak or market poultry die-offs from suspected HPAI H5N1. Despite exposure to sick poultry, no farm or market poultry workers were seropositive for HPAI H5N1 virus antibodies (95% confidence interval 0-1%.

  1. Validation of a commercially available indirect ELISA using a nucleocapside recombinant protein for detection of Schmallenberg virus antibodies.

    Directory of Open Access Journals (Sweden)

    Emmanuel Bréard

    Full Text Available A newly developed Enzym Like Immuno Sorbant Assay (ELISA based on the recombinant nucleocapsid protein (N of Schmallenberg virus (SBV was evaluated and validated for the detection of SBV-specific IgG antibodies in ruminant sera by three European Reference Laboratories. Validation data sets derived from sheep, goat and bovine sera collected in France and Germany (n = 1515 in 2011 and 2012 were categorized according to the results of a virus neutralization test (VNT or an indirect immuno-fluorescence assay (IFA. The specificity was evaluated with 1364 sera from sheep, goat and bovine collected in France and Belgium before 2009. Overall agreement between VNT and ELISA was 98.9% and 98.3% between VNT and IFA, indicating a very good concordance between the different techniques. Although cross-reactions with other Orthobunyavirus from the Simbu serogroup viruses might occur, it is a highly sensitive, specific and robust ELISA-test validated to detect anti-SBV antibodies. This test can be applied for SBV sero-diagnostics and disease-surveillance studies in ruminant species in Europe.

  2. Bovine respiratory syncytial virus and bovine coronavirus antibodies in bulk tank milk - risk factors and spatial analysis.

    Science.gov (United States)

    Toftaker, Ingrid; Sanchez, Javier; Stokstad, Maria; Nødtvedt, Ane

    2016-10-01

    Bovine respiratory syncytial virus (BRSV) and bovine coronavirus (BCoV) are considered widespread among cattle in Norway and worldwide. This cross-sectional study was conducted based on antibody-ELISA of bulk tank milk (BTM) from 1347 herds in two neighboring counties in western Norway. The study aims were to determine the seroprevalence at herd level, to evaluate risk factors for BRSV and BCoV seropositivity, and to assess how these factors were associated with the spatial distribution of positive herds. The overall prevalence of BRSV and BCoV positive herds in the region was 46.2% and 72.2%, respectively. Isopleth maps of the prevalence risk distribution showed large differences in prevalence risk across the study area, with the highest prevalence in the northern region. Common risk factors of importance for both viruses were herd size, geographic location, and proximity to neighbors. Seropositivity for one virus was associated with increased odds of seropositivity for the other virus. Purchase of livestock was an additional risk factor for BCoV seropositivity, included in the model as in-degree, which was defined as the number of incoming movements from individual herds, through animal purchase, over a period of five years. Local dependence and the contribution of risk factors to this effect were assessed using the residuals from two logistic regression models for each virus. One model contained only the x- and y- coordinates as predictors, the other had all significant predictors included. Spatial clusters of high values of residuals were detected using the normal model of the spatial scan statistic and visualized on maps. Adjusting for the risk factors in the final models had different impact on the spatial clusters for the two viruses: For BRSV the number of clusters was reduced from six to four, for BCoV the number of clusters remained the same, however the log-likelihood ratios changed notably. This indicates that geographical differences in proximity to

  3. Antibodies against rabies virus in dogs with and without history of vaccination in Santa Maria - RS - Brazil

    Directory of Open Access Journals (Sweden)

    Karina Gonzalez Fernandes

    2017-10-01

    Full Text Available ABSTRACT: The present study investigated the frequency and magnitude of neutralizing antibodies to rabies virus (RABV in dogs with and without historic of vaccination in Santa Maria/RS. Group A included serum samples from 440 dogs with recent historic of vaccination against rabies, obtained during the 2015 rabies vaccination campaign. Group B included 300 serum samples from dogs submitted to the Veterinary Hospital of the Universidade Federal de Santa Maria in 2015, whose historic of rabies vaccination was unknown. Serum samples were submitted to the rapid fluorescent focus inhibition test (RFFIT to detect neutralizing antibodies against RABV. In group A, 70.6% (310/440 of the samples had neutralizing antibody titers ≥0.5 international units per milliliter (IU mL-1, considered an indicative of protection against rabies by the World Health Organization. However, approximately 30% of the dogs did not contain antibodies in adequate levels. In group B, 42.3% (127/300 of the samples contained neutralizing antibody titers ≥0.5IU mL-1 and 57.7% (173/300 were negative or contained titers below of the value considered immunized. These results demonstrate that an important proportion of vaccinated dogs (~30% did not develop adequate antibody levels, mainly those receiving a single vaccine dose. Serologic testing of animals with unknown historic of vaccination revealed relatively low vaccine coverage in the general dog population. Thus, reformulation of immunization strategies - especially the recommendation of a boost vaccination 30 days after the primary dose - and extension of vaccination campaigns are necessary to reach adequate levels and coverage of immunity against RABV in the canine population.

  4. Immunohistochemical detection of VHS virus in paraffin-embedded specimens of rainbow trout (Oncorhynchus mykiss); The influence of primary antibody, fixative, and antigen unmasking on method sensitivity

    DEFF Research Database (Denmark)

    Evensen, O.; Olesen, Niels Jørgen

    1997-01-01

    performed on parallel specimens, and the virus titer (TCID50/ml) was determined. Purified nucleocapsid protein (N-protein) of the virus was incorporated in an artificial antigen substrate (polymerized bovine serum albumin), fixed as described above, and embedded in paraffin wax. Microwave unmasking...... was performed an formalin-, PLP-, and Bouin's fluid-fixed specimens. The presence of virus peptides in situ or N-protein in the artificial antigen substrates was Visualized using an immunohistochemical method based on alkaline phosphatase or peroxidase and one polyclonal and five monoclonal polypeptide......-specific antibodies. VHS virus was identified in situ in specimens with high virus titers (10(7-8) TCID50/ml) regardless of the fixative and without the need of an unmasking procedure. A pronounced masking effect was observed for the cross-linking formalin and PLP fixatives. Regardless of the primary antibodies used...

  5. Epstein-Barr virus associated acute hepatitis with cross-reacting antibodies to other herpes viruses in immunocompetent patients: report of two cases.

    Science.gov (United States)

    Gupta, Ekta; Bhatia, Vikram; Choudhary, Aashish; Rastogi, Archana; Gupta, Naveen L

    2013-03-01

    Epstein-Barr virus (EBV) is the causative agent of infectious mononucleosis (IM) which is characterized by the triad of fever, sore throat, and lymphadenopathy. Self-limited, mild liver function test abnormalities are seen in IM. Acute hepatitis in primary EBV infection is uncommon. Serum transaminases are elevated but are less than fivefold the normal levels in most cases and rarely exceed 10 times the normal levels in primary EBV infections especially in elderly. Laboratory diagnosis of acute EBV infection is by serological assays confirming the presence of EBV viral capsid antigen (VCA) IgM antibodies. Due to antigenic cross-reactivity with Herpes viruses, serological assays lack specificity; hence specific molecular diagnostic methods are required for confirmation of the etiology. The present report describes two cases of acute hepatitis caused by infection with EBV which had indistinguishable clinical features and biochemical markers from acute hepatitis caused by hepatotropic viruses such as hepatitis viruses A-E. The diagnosis of infection by EBV was confirmed by detection of EBV DNA in blood of both the patients and EBV DNA in the liver tissue of one of the patients. Copyright © 2013 Wiley Periodicals, Inc.

  6. Serosurvey for antibodies to malignant catarrhal fever-associated viruses in free-living and captive cervids in Germany.

    Science.gov (United States)

    Frölich, K; Li, H; Müller-Doblies, U

    1998-10-01

    A total of 486 serum samples collected from several species of both free-living and captive cervids in Germany was examined for antibodies against malignant catarrhal fever (MCF)-associated viruses (MCFV) by a competitive-inhibition enzyme-linked immunosorbent assay (CI-ELISA). Eleven (2%) of these samples were positive for antibodies against MCFV. Among 157 serum samples collected from 16 different species of captive deer including four (7%) of 54 fallow deer and one (7%) of 14 sika deer (Cervus nippon) were seropositive. Among 329 samples from three species of free-ranging deer, including 253 roe deer (Capreolus capreolus), 22 red deer (Cervus elaphus) and 54 fallow deer (Cervus dama), only fallow deer were antibody-positive. Of the 25 fallow deer samples collected between 1990 and 1993, four (16%) were seropositive. Among 29 free-ranging fallow deer samples collected in the hunting period 1996-1997, antibodies to MCFV were detected in two (7%) of these sera. All of these fallow deer samples were collected from a circumscribed area in northern Germany. In the same area a high seroprevalence (72%) to MCFV was observed in domestic sheep (n = 50). Among 20 sheep samples (buffy coat) and 15 fallow deer samples (spleen or lymph nodes) examined for ovine herpesvirus 2 (OvHV-2) by PCR, all 20 sheep samples examined were OvHV-2 positive, but all of the 15 fallow deer samples, including seven seropositive deer, were OvHV-2 negative.

  7. Anti-human immunodeficiency virus-1 antibody titers in injection drug users compared to sexually infected individuals

    Directory of Open Access Journals (Sweden)

    Bongertz Vera

    2003-01-01

    Full Text Available Sera from infected injection drug users (IDU have shown to have antibodies against synthetic human immunodeficiency virus-1 (HIV-1 envelope peptides more frequently. In this study, reactivity of 48 IDU plasma were compared to 60 plasmas obtained from sexually infected individuals (S. The overall reactivity of plasma from IDU compared to S was higher, and the reactivity titers were much higher for IDU plasma than S. IDU plasma also showed a broader antibody response. The higher reactivity titers were observed mainly for the gp41 immunodominant epitope and V3 peptides corresponding to the consensus sequences of HIV-1 subtypes/variants prevalent in Brazil (B, F, C indicating the specificity in the higher immune response of IDU.

  8. Anti-human immunodeficiency virus-1 antibody titers in injection drug users compared to sexually infected individuals.

    Science.gov (United States)

    Bongertz, Vera; Ouverney, Elaine Priscilla; Teixeira, Sylvia L M; Silva-de-Jesus, Carlos; Hacker, Mariana A; Morgado, Mariza G; Bastos, Francisco I

    2003-03-01

    Sera from infected injection drug users (IDU) have shown to have antibodies against synthetic human immunodeficiency virus-1 (HIV-1) envelope peptides more frequently. In this study, reactivity of 48 IDU plasma were compared to 60 plasmas obtained from sexually infected individuals (S). The overall reactivity of plasma from IDU compared to S was higher, and the reactivity titers were much higher for IDU plasma than S. IDU plasma also showed a broader antibody response. The higher reactivity titers were observed mainly for the gp41 immunodominant epitope and V3 peptides corresponding to the consensus sequences of HIV-1 subtypes/variants prevalent in Brazil (B, F, C) indicating the specificity in the higher immune response of IDU.

  9. An enzyme-linked immunosorbent assay for detection of avian influenza virus subtypes H5 and H7 antibodies

    DEFF Research Database (Denmark)

    Jensen, Trine Hammer; Ajjouri, Gitte; Handberg, Kurt

    2013-01-01

    subtypes H5 and H7. The ELISAs were evaluated with polyclonal chicken anti-AIV antibodies against AIV subtypes: H1N2, H5N2, H5N7, H7N1, H7N7, H9N9, H10N4 and H16N3. RESULTS: Both the H5 and H7 ELISA proved to have a high sensitivity and specificity and the ELISAs detected H5 and H7 antibodies earlier......BACKGROUND: Avian influenza virus (AIV) subtypes H5 and H7 attracts particular attention because of the risk of their potential pathogenicity in poultry. The haemagglutination inhibition (HI) test is widely used as subtype specific test for serological diagnostics despite the laborious nature...

  10. 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

    2004-11-01

    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.

  11. A serological survey for antibodies against foot-and-mouth disease virus (FMDV) in domestic pigs during outbreaks in Kenya

    DEFF Research Database (Denmark)

    Wekesa, Sabenzia N.; Namatovu, Alice; Sangula, Abraham K.

    2014-01-01

    Foot-and-mouth disease (FMD) is endemic in Kenya and has been well studied in cattle, but not in pigs, yet the role of pigs is recognised in FMD-free areas. This study investigated the presence of antibodies against FMD virus (FMDV) in pigs sampled during a countrywide random survey for FMD...... in cattle coinciding with SAT 1 FMDV outbreaks in cattle. A total of 191 serum samples were collected from clinically healthy pigs in 17 districts. Forty-two of the 191 sera were from pigs vaccinated against serotypes O/A/SAT 2 FMDV. Antibodies against FMDV non-structural proteins were found in sera from 30...... neutralisation test (VNT). Due to high degree of agreement between the two ELISAs, it was concluded that positive pigs had been infected with FMDV. Implications of these results for the role of pigs in the epidemiology of FMD in Kenya are discussed, and in-depth studies are recommended....

  12. Smooth muscle antibodies and cryoglobulinemia are associated with advanced liver fibrosis in Brazilian hepatitis C virus carriers

    Directory of Open Access Journals (Sweden)

    Luis Jesuino de Oliveira Andrade

    Full Text Available Cryoglobulinemia and non-organ-specific-autoantibody are biomarkers of autoimmunity of the chronic infection caused by hepatitis C virus (HCV. In this work, we report the association between the presence of smooth muscle antibodies (SMA and cryoglobulinemia and chronic liver disease in HCV carriers. Sixty-five untreated HCV patients, 38 women and 27 men were included in this study. Cryoglobulinemia was tested by cryoprecipitation, SMA by indirect fluorescent antibody test, and liver fibrosis and hepatocellular inflammation activity was investigated by histology of liver biopsy using the METAVIR score. The prevalence of SMA in the patients was 33.8% and cryoglobulinemia was demonstrated in 36.9% patients. Cryoglobulinemia and SMA seropositivity was associated with advanced fibrosis (p < 0.05. The presence of SMA and cryoglobulinemia was not associated with hepatocellular inflammation activity, age, carrier gender or HCV genotype. We concluded that liver biopsy should be recommended for HCV carriers that are seropositive for SMA or cryoglobulinemia.

  13. Temporal variation in viral hemorrhagic septicemia virus antibodies in freshwater drum (Aplodinotus grunniens) indicates cyclic transmission in Lake Winnebago, Wisconsin

    Science.gov (United States)

    Wilson-Rothering, Anna; Marcquenski, Susan; Koenigs, Ryan P.; Bruch, Ronald; Kamke, Kendall; Isermann, Daniel A.; Thurman, Andrew; Toohey-Kurth, Kathy; Goldberg, Tony

    2015-01-01

    Viral hemorrhagic septicemia virus (VHSV) is an emerging pathogen that causes mass mortality in multiple fish species. In 2007, the Great Lakes freshwater strain, type IVb, caused a large die-off of freshwater drum (Aplodinotus grunniens) in Lake Winnebago, Wisconsin, USA. To evaluate the persistence and transmission of VHSV, freshwater drum from Lake Winnebago were tested for antibodies to the virus using recently developed virus neutralization (VN) and enzyme-linked immunosorbent (ELISA) assays. Samples were also tested by real-time reverse transcription-PCR (rRT-PCR) to detect viral RNA. Of 548 serum samples tested, 44 (8.03%) were positive by VN (titers ranging from 1:16 to 1:1,024) and 45 (8.21%) were positive by ELISA, including 7 fish positive by both assays. Antibody prevalence increased with age and was higher in one northwestern area of Lake Winnebago than in other areas. Of 3,864 tissues sampled from 551 fish, 1 spleen and 1 kidney sample from a single adult female fish collected in the spring of 2012 tested positive for VHSV by rRT-PCR, and serum from the same fish tested positive by VN and ELISA. These results suggest that VHSV persists and viral transmission may be active in Lake Winnebago even in years following outbreaks and that wild fish may survive VHSV infection and maintain detectable antibody titers while harboring viral RNA. Influxes of immunologically naive juvenile fish through recruitment may reduce herd immunity, allow VHSV to persist, and drive superannual cycles of transmission that may sporadically manifest as fish kills.

  14. Development and evaluation of an anti-rabies virus phosphoprotein-specific monoclonal antibody for detection of rabies neutralizing antibodies using RFFIT.

    Science.gov (United States)

    Um, Jihye; Chun, Byung Chul; Lee, Yeong Seon; Hwang, Kyu Jam; Yang, Dong-Kun; Park, Jun-Sun; Kim, Su Yeon

    2017-12-01

    Rabies is a major public health problem with a fatality rate close to 100%; however, complete prevention can be achieved through pre- or post-exposure prophylaxis. The rapid fluorescent focus inhibition test (RFFIT) is one of the recommended testing methods to determine the production of neutralizing antibodies after vaccination. Here, we report the development of a new monoclonal antibody (mAb) designed to react specifically with Rabies virus (RABV) phosphoprotein (P protein), and the evaluation of its applicability to the RFFIT and its effectiveness as a diagnostic reagent for human rabies. The mAb KGH P 16B8 was produced to target the P protein of the Korean KGH RABV strain. An indirect immunofluorescence assay (IFA) was conducted to detect various strains of RABV in various cell lines. Alexa-conjugated KGH P 16B8 (16B8-Alexa) was developed for the RFFIT. The IFA test could detect RABV up to a 1:2,500 dilution, with a detection limit comparable to that of a commercial diagnostic reagent. The sensitivity, specificity, positive predictive value, and negative predictive value of the RFFIT using 16B8-Alexa in 414 clinical specimens were 98.67%, 99.47%, 99.55%, and 98.42%, respectively. The results of the RFFIT with 16B8-Alexa were strongly correlated with those obtained using an existing commercial diagnostic reagent (r = 0.995, prabies neutralizing antibody titer and establish a diagnosis in human. Thus, 16B8-Alexa is expected to serve as an alternative diagnostic reagent that is widely accessible, with potentially broad applications beyond those of the RFFIT in Korea. Further studies with 16B8-Alexa should provide insight into the immunological mechanism of the P protein of Korean RABV.

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

    International Nuclear Information System (INIS)

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

    1993-01-01

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

  16. Antibody Persistence in Adults Two Years after Vaccination with an H1N1 2009 Pandemic Influenza Virus-Like Particle Vaccine.

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    Nuriban Valero-Pacheco

    Full Text Available The influenza virus is a human pathogen that causes epidemics every year, as well as potential pandemic outbreaks, as occurred in 2009. Vaccination has proven to be sufficient in the prevention and containment of viral spreading. In addition to the current egg-based vaccines, new and promising vaccine platforms, such as cell culture-derived vaccines that include virus-like particles (VLPs, have been developed. VLPs have been shown to be both safe and immunogenic against influenza infections. Although antibody persistence has been studied in traditional egg-based influenza vaccines, studies on antibody response durations induced by VLP influenza vaccines in humans are scarce. Here, we show that subjects vaccinated with an insect cell-derived VLP vaccine, in the midst of the 2009 H1N1 influenza pandemic outbreak in Mexico City, showed antibody persistence up to 24 months post-vaccination. Additionally, we found that subjects that reported being revaccinated with a subsequent inactivated influenza virus vaccine showed higher antibody titres to the pandemic influenza virus than those who were not revaccinated. These findings provide insights into the duration of the antibody responses elicited by an insect cell-derived pandemic influenza VLP vaccine and the possible effects of subsequent influenza vaccination on antibody persistence induced by this VLP vaccine in humans.

  17. Absence of cytotoxic antibody to human immunodeficiency virus-infected cells in humans and its induction in animals after infection or immunization with purified envelope glycoprotein gp120

    International Nuclear Information System (INIS)

    Nara, P.L.; Robey, W.G.; Gonda, M.A.; Carter, S.G.; Fischinger, P.J.

    1987-01-01

    The presence of antibody-dependent complement-mediated cytotoxicity (ACC) was assessed in humans and chimpanzees, which are capable of infection with human immunodeficiency virus isolate HTLV-IIIb, and examined in the goat after immunization with the major viral glycoprotein (gp120) of HTLV-IIIb. In infected humans no antibody mediating ACC was observed regardless of the status of disease. Even healthy individuals with high-titer, broadly reactive, neutralizing antibodies has no ACC. In contrast, chimpanzees infected with HTLV-IIIb, from whom virus could be isolated, not only had neutralizing antibody but also antibodies broadly reactive in ACC, even against distantly related human immunodeficiency virus isolates, as well as against their own reisolated virus. In the goat, the gp120 of HTLV-IIIb induced a highly type-specific response as measured by both ACC and flow cytofluorometry of live infected H9 cells. Normal human cells were not subject to ACC by animal anti-HTLV-III gp120-specific sera. Induction of ACC and neutralizing antibody were closely correlated in the animal experimental models but not in humans. The presence of ACC in gp120-inoculated goats and HTLV-III-infected chimpanzees represent a qualitative difference that may be important in the quest for the elicitation of a protective immunity in humans

  18. Prevalence of Hepatitis C Virus Antibody in Patients With Sexually Transmitted Diseases Attending a Harrisburg, PA, STD Clinic

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    Robert L. Sautter

    1994-01-01

    Full Text Available Objective: The prevalence of hepatitis B and hepatitis C in a sexually transmitted disease (STD clinic population was studied, along with the prevalence of various STD agents, in an attempt to identify possible STD markers for the hepatitis C virus and help delineate the role of hepatitis C as an STD. The hepatitis C antibody rates found in the STD clinic were also compared with those found among patients attending a local OB/GYN clinic and those enrolled in a blood donor program, all from the same geographical area.

  19. Prevalence of serotype specific antibody to equine encephalosis virus in Thoroughbred yearlings South Africa (1999-2004

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    P. G. Howell

    2008-08-01

    Full Text Available Cohorts of yearlings were sampled over a period of 6 years in a retrospective serological survey to establish the annual prevalence of serotype specific antibody to equine encephalosis virus on Thoroughbred stud farms distributed within defined geographical regions of South Africa. Seasonal seroprevalence varied between 3.6% and 34.7%, revealing both single and multiple serotype infections in an individual yearling. During the course of this study serotypes 1 and 6 were most frequently and extensively identified while the remaining serotypes 2, 3, 4, 5 and 7 were all identified as sporadic and localized in fections affecting only individual horses. This study of the seasonal prevalence of equine encephalosis virus has a corollary and serves as a useful model in the seasonal incidence of the serotypes of African horse sickness and bluetongue in regions where the respective diseases are endemic.

  20. Detection of antibody responses by using haemagglutination inhibiton test and the protection titer of avian influenza virus H5N1 subtype

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    Risa Indriani

    2004-10-01

    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.

  1. The initial antibody response to HIV-1: induction of ineffective early B cell responses against GP41 by the transmitted/founder virus

    Energy Technology Data Exchange (ETDEWEB)

    Chavez, Leslie L [Los Alamos National Laboratory; Perelson, Alan [Los Alamos National Laboratory

    2008-01-01

    A window of opportunity for immune responses to extinguish HIV -1 exists from the moment of transmission through establishment of the latent pool of HIV -I-infected cells. A critical time to study the initial immune responses to the transmitted/founder virus is the eclipse phase of HIV-1 infection (time from transmission to the first appearance of plasma virus) but, to date, this period has been logistically difficult to analyze. Studies in non-human primates challenged with chimeric simianhuman immunodeficiency virus have shown that neutralizing antibodies, when present at the time of infection, can prevent virus infection.

  2. Canine Parvovirus (CPV) Vaccination: Comparison of Neutralizing Antibody Responses in Pups after Inoculation with CPV2 or CPV2b Modified Live Virus Vaccine

    Science.gov (United States)

    Pratelli, Annamaria; Cavalli, Alessandra; Martella, Vito; Tempesta, Maria; Decaro, Nicola; Carmichael, Leland Eugene; Buonavoglia, Canio

    2001-01-01

    Canine parvovirus type 2 (CPV2) emerged in 1978 as causative agent of a new disease of dogs. New antigenic variants (biotypes), designated CPV2a and CPV2b, became widespread during 1979 to 1980 and 1984, respectively. At the present time the original CPV2 has disappeared in the dog population and has been replaced by the two new viruses. In the present study the comparison of neutralizing antibody titers in two groups of pups (18 pups in each group) inoculated with CPV2 and CPV2b modified live virus vaccines is reported. Using the hemagglutination inhibition (HI) test, relevant differences between antibody titers, against either the homologous or the heterologous virus, were not constantly observed. Using the neutralization (Nt) test, however, the pups inoculated with CPV2 had antibody titers which were approximately 30 times higher to the homologous virus (mean, 4,732) than to the heterologous virus (CPV2b) (mean, 162). The results of these experiments support two conclusions: (i) the HI test may not always accurately evaluate the true immune status of dogs with respect to CPV, and (ii) dogs inoculated with CPV2 vaccine develop relatively low Nt antibody titers against the heterologous virus (CPV2b). These data may suggest an advantage for new vaccines, considering that most presently licensed vaccines are produced with CPV2, which no longer exists in the dog population. PMID:11329467

  3. Canine parvovirus (CPV) vaccination: comparison of neutralizing antibody responses in pups after inoculation with CPV2 or CPV2b modified live virus vaccine.

    Science.gov (United States)

    Pratelli, A; Cavalli, A; Martella, V; Tempesta, M; Decaro, N; Carmichael, L E; Buonavoglia, C

    2001-05-01

    Canine parvovirus type 2 (CPV2) emerged in 1978 as causative agent of a new disease of dogs. New antigenic variants (biotypes), designated CPV2a and CPV2b, became widespread during 1979 to 1980 and 1984, respectively. At the present time the original CPV2 has disappeared in the dog population and has been replaced by the two new viruses. In the present study the comparison of neutralizing antibody titers in two groups of pups (18 pups in each group) inoculated with CPV2 and CPV2b modified live virus vaccines is reported. Using the hemagglutination inhibition (HI) test, relevant differences between antibody titers, against either the homologous or the heterologous virus, were not constantly observed. Using the neutralization (Nt) test, however, the pups inoculated with CPV2 had antibody titers which were approximately 30 times higher to the homologous virus (mean, 4,732) than to the heterologous virus (CPV2b) (mean, 162). The results of these experiments support two conclusions: (i) the HI test may not always accurately evaluate the true immune status of dogs with respect to CPV, and (ii) dogs inoculated with CPV2 vaccine develop relatively low Nt antibody titers against the heterologous virus (CPV2b). These data may suggest an advantage for new vaccines, considering that most presently licensed vaccines are produced with CPV2, which no longer exists in the dog population.

  4. Development of a multiplex lateral flow strip test for foot-and-mouth disease virus detection using monoclonal antibodies.

    Science.gov (United States)

    Yang, Ming; Caterer, Nigel R; Xu, Wanhong; Goolia, Melissa

    2015-09-01

    Foot-and-mouth disease (FMD) is one of the world's most highly contagious animal diseases with tremendous economic consequences. A rapid and specific test for FMD diagnosis at the site of a suspected outbreak is crucial for the implementation of control measures. This project developed a multiplex lateral flow immunochromatographic strip test (multiplex-LFI) for the rapid detection and serotyping of FMD viruses. The monoclonal antibodies (mAbs) against serotypes O, A, and Asia 1 were used as capture mAbs. The mAbs were conjugated with fluorescein, rhodamine or biotin for serotype O, A and Asia 1, respectively. The detection mAbs which consisted of a serotype-independent mAb in combination with one serotype A-specific mAb and one Asia 1-specific mAb, were each colloidal gold-conjugated. The strips used in this study contained one control line and three test lines, which corresponded to one of the three serotypes, O, A or Asia 1. The newly developed multiplex-LFI strip test specifically identified serotype O (n=46), A (n=45) and Asia 1 (n=17) in all tested field isolates. The sensitivity of this strip test was comparable to the double antibody sandwich ELISA for serotypes O and A, but lower than the ELISA for serotype Asia 1. The multiplex-LFI strip test identified all tissue suspensions from animals that were experimentally inoculated with serotypes O, A or Asia 1. FMD viruses were detected in 38% and 50% of the swab samples from the lesion areas of experimentally inoculated sheep for serotypes O and A, respectively. The capability of the multiplex-LFI strip tests to produce rapid results with high specificity for FMD viruses of multiple serotypes makes this test a valuable tool to detect FMD viruses at outbreak sites. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

  5. An influenza A virus (H7N9) anti-neuraminidase monoclonal antibody with prophylactic and therapeutic activity in vivo

    Science.gov (United States)

    Wilson, Jason R.; Guo, Zhu; Reber, Adrian; Kamal, Ram P.; Music, Nedzad; Gansebom, Shane; Bai, Yaohui; Levine, Min; Carney, Paul; Tzeng, Wen-Pin; Stevens, James; York, Ian A.

    2017-01-01

    Zoonotic A(H7N9) avian influenza viruses emerged in China in 2013 and continue to be a threat to human public health, having infected over 800 individuals with a mortality rate approaching 40%. Treatment options for people infected with A(H7N9) include the use of neuraminidase (NA) inhibitors. However, like other influenza viruses, A(H7N9) can become resistant to these drugs. The use of monoclonal antibodies is a rapidly developing strategy for controlling influenza virus infection. Here we generated a murine monoclonal antibody (3c10-3) directed against the NA of A(H7N9) and show that prophylactic systemic administration of 3c10-3 fully protected mice from lethal challenge with wild-type A/Anhui/1/2013 (H7N9). Further, post-infection treatment with a single systemic dose of 3c10-3 at either 24, 48 or 72 h post A(H7N9) challenge resulted in both dose- and time-dependent protection of up to 100% of mice, demonstrating therapeutic potential for 3c10-3. Epitope mapping revealed that 3c10-3 binds near the enzyme active site of NA, and functional characterization showed that 3c10-3 inhibits the enzyme activity of NA and restricts the cell-to-cell spread of the virus in cultured cells. Affinity analysis also revealed that 3c10-3 binds equally well to recombinant NA of wild-type A/Anhui/1/2013 and to a variant NA carrying a R289K mutation known to infer NAI resistance. These results suggest that 3c10-3 has the potential to be used as a therapeutic to treat A(H7N9) infections either as an alternative to, or in combination with, current NA antiviral inhibitors. PMID:27713074

  6. Development of a Sensitive and Specific Serological Assay Based on Luminex Technology for Detection of Antibodies to Zaire Ebola Virus.

    Science.gov (United States)

    Ayouba, Ahidjo; Touré, Abdoulaye; Butel, Christelle; Keita, Alpha Kabinet; Binetruy, Florian; Sow, Mamadou S; Foulongne, Vincent; Delaporte, Eric; Peeters, Martine

    2017-01-01

    The recent Zaire Ebola virus (EBOV) outbreak in West Africa illustrates clearly the need for additional studies with humans and animals to elucidate the ecology of Ebola viruses (EBVs). In this study, we developed a serological assay based on the Luminex technology. Nine recombinant proteins representing different viral regions (nucleoprotein [NP], 40-kDa viral protein [VP40], and glycoprotein [GP]) from four of the five EBV lineages were used. Samples from 94 survivors of the EBOV outbreak in Guinea and negative samples from 108 patients in France were used to calculate test performance for EBOV detection and cross-reaction with other Ebola virus lineages. For EBOV antibody detection, sensitivities of 95.7%, 96.8%, and 92.5% and specificities of 94.4%, 95.4%, and 96.3% for NP, GP, and VP40, respectively, were observed. All EBOV-negative samples that presented a reaction, except for one, interacted with a single antigen, whereas almost all samples from EBOV survivors were simultaneously reactive with NP and GP (90/94) or with NP, GP, and VP40 (87/94). Considering as positive for past EBOV infection only samples that reacted with EBOV NP and GP, sensitivity was 95.7% and specificity increased to 99.1%. Comparing results with commercial EBOV NP and GP enzyme-linked immunosorbent assays (ELISAs; Alpha Diagnostic, San Antonio, TX), lower sensitivity (92.5%) and high specificity (100%) were observed with the same positivity criteria. Samples from EBOV survivors cross-reacted with GP from Sudan Ebola virus (GP-SUDV) (81.9%), GP from Bundibugyo Ebola virus (GP-BDBV) (51.1%), GP from Reston Ebola virus (GP-RESTV) (9.6%), VP40-SUDV (76.6%), and VP40-BDBV (38.3%). Overall, we developed a sensitive and specific high-throughput serological assay, and defined an algorithm, for epidemiological surveys with humans. Copyright © 2016 American Society for Microbiology.

  7. Isolation of Panels of Llama Single-Domain Antibody Fragments Binding All Nine Neuraminidase Subtypes of Influenza A Virus

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    Guus Koch

    2013-04-01

    Full Text Available Avian influenza A virus comprises sixteen hemagglutinin (HA and nine neuraminidase (NA subtypes (N1–N9. To isolate llama single-domain antibody fragments (VHHs against all N subtypes, four llamas were immunized with mixtures of influenza viruses. Selections using influenza virus yielded predominantly VHHs binding to the highly immunogenic HA and nucleoprotein. However, selection using enzymatically active recombinant NA (rNA protein enabled us to isolate NA binding VHHs. Some isolated VHHs cross-reacted to other N subtypes. These were subsequently used for the capture of N subtypes that could not be produced as recombinant protein (rN6 or were enzymatically inactive (rN1, rN5 in phage display selection, yielding novel VHHs. In total we isolated 188 NA binding VHHs, 64 of which were expressed in yeast. Most VHHs specifically recognize a single N subtype, but some VHHs cross-react with other N-subtypes. At least one VHH bound to all N subtypes, except N4, identifying a conserved antigenic site. Thus, this work (1 describes methods for isolating NA binding VHHs, (2 illustrates the suitability of llama immunization with multiple antigens for retrieving many binders against different antigens and (3 describes 64 novel NA binding VHHs, including a broadly reactive VHH, which can be used in various assays for influenza virus subtyping, detection or serology.

  8. Occurrence and properties of antibodies against virus-associated transformation proteins in radiation-induced osteosarcomas in mice

    International Nuclear Information System (INIS)

    Hofherr, J.

    1983-01-01

    In this thesis it was looked if there is an immunresponse against such viral oncogene products in mice with radiation-induced osteosarcomas. Sera from mice with transplantable radiation-induced osteosacomas showed strong cytotoxicity against cells from a Moloney sarcoma virus-induced tumor and to a smaller extent also against FBJ osteosarcoma virus-transformed nonproducer cells. The cytotoxic activity was bound to the IgM fraction of the sera. Immunprecipitation of 35 S-methionine labelled virus- or radiation-transformed cells with cytotoxic sera showed on PAGE two proteins of molecular weights (m.w.) of about 50-55 kD. A protein of about 38 kD was expressed only in transformed cells whereas another protein of about 43 kD was seen in all cells except in uninfected muscle cells of adult mice. In order to further characterize the nature of these antigens immunprecipitates with unlabelled cells were tested in a protein kinase assay with gamma 32 P ATP and analysed on PAGE. Phosphorylation of proteins occured predominantly of more than 70 kD m.w., of about 68 kD, 50-55 kD and to a lesser extent also of about 32, 34 and 39 kD. The phosphorylation site of the proteins was at serine and threonine residues. These results indicate that mice with radiation-induced osteosarkomas develop antibodies against 'in vivo' and 'in vitro'-sarcoma virus transformed cells. (orig./MG) [de

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

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    Zhao Qinjian

    2012-02-01

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

  10. Preparasi Imunoglobulin G Kelinci sebagai Antigen Penginduksi Antibodi Spesifik Terhadap Virus Avian Influenza H5N1 Strain Legok

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    Ketut Karuni Nyanakumari Natih

    2010-06-01

    Full Text Available The aim of this research was to prepare rabbit Immunoglobulin G as anti-idiotype antibody (Ab2 ofAvian Influenza Virus (AIV H5N1. A polyclonal antibody was collected from guinea pigs immunized withinactivated AI vaccine H5N1of Legok strain. Antibody of H5N1 AI in serum was detected by Agar gelprecipitation test (AGPT and an Inhibition Hemmaglutination test (IHT. The highest titre of antibodywas obtained one week after the third immunization. Serum of guinea pigs containing IgG was purifiedusing the Montage Antibody purification kit & spin column with Prosep A media (Millipore. The AI H5N1IgG concentration was 8 mg/ml. AI H5N1 IgG, was then digested with pepsin to obtain F(ab2 fraction andwas called Ab1. The concentration of IgG and F(ab2 and purity of IgG were determined by UVspectrophotometer which showed Ab1 concentration 1 mg/ml. Molecular weight was estimated by sodiumdodecyl sulfate- polyacrilamide gel electrophoresis (SDS-PAGE. Ab2 was produced by immunization ofrabbit with Ab1. The first immunization was carried out by subcutaneous injection with 500 ?g of Ab1emulsified in Complete Freund Adjuvant. The immunization was repeated with the same dose of Ab1emulsified in Incomplete Freund Adjuvan at 1 week intervals. One week after the second immunization,rabbit’s serum was harvested and IgG was purified using the Montage Antibody purification kit & spincolumn with Prosep A media (Millipore. The rabbit IgG, called Ab2, was an anti-idiotypic antibody againstAIV-H5N1. In AGPT, a precipitation line appeared between Ab1 and Ab2. A partial reaction appearedbetween Ab2 and the AI H5N1 antigen was also detected. The results indicated that Ab2 is a possiblecandidate of imunogen for protection against an AI virus H5N1 infection.

  11. Anti-Bovine Programmed Death-1 Rat–Bovine Chimeric Antibody for Immunotherapy of Bovine Leukemia Virus Infection in Cattle

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    Tomohiro Okagawa

    2017-06-01

    Full Text Available Blockade of immunoinhibitory molecules, such as programmed death-1 (PD-1/PD-ligand 1 (PD-L1, is a promising strategy for reinvigorating exhausted T cells and preventing disease progression in a variety of chronic infections. Application of this therapeutic strategy to cattle requires bovinized chimeric antibody targeting immunoinhibitory molecules. In this study, anti-bovine PD-1 rat–bovine chimeric monoclonal antibody 5D2 (Boch5D2 was constructed with mammalian expression systems, and its biochemical function and antiviral effect were characterized in vitro and in vivo using cattle infected with bovine leukemia virus (BLV. Purified Boch5D2 was capable of detecting bovine PD-1 molecules expressed on cell membranes in flow cytometric analysis. In particular, Biacore analysis determined that the binding affinity of Boch5D2 to bovine PD-1 protein was similar to that of the original anti-bovine PD-1 rat monoclonal antibody 5D2. Boch5D2 was also capable of blocking PD-1/PD-L1 binding at the same level as 5D2. The immunomodulatory and therapeutic effects of Boch5D2 were evaluated by in vivo administration of the antibody to a BLV-infected calf. Inoculated Boch5D2 was sustained in the serum for a longer period. Boch5D2 inoculation resulted in activation of the proliferation of BLV-specific CD4+ T cells and decrease in the proviral load of BLV in the peripheral blood. This study demonstrates that Boch5D2 retains an equivalent biochemical function to that of the original antibody 5D2 and is a candidate therapeutic agent for regulating antiviral immune response in vivo. Clinical efficacy of PD-1/PD-L1 blockade awaits further experimentation with a large number of animals.

  12. Application of solid-phase radioimmunoassay in determining antibodies to Aujeszky's disease virus in blood serum of vaccinated pigs

    Energy Technology Data Exchange (ETDEWEB)

    Rodak, L.; Smid, B.; Valicek, L. (Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia))

    1983-11-01

    In the blood sera of pigs vaccinated with inactivated vaccines manufactured by three different manufacturers the RIA method was used to determine the specific antibodies to the virus of Aujeszky's disease. In certain groups of vaccinated pigs the results of the RIA examination are unfavourably affected by the bond of antibodies to the cellular antigenous determinants. This proves that following vaccination antibodies are formed not only against the viral antigen but also against the antigens of cells on which the vaccination virus is propagated. These shortcomings are eliminated by the use of suitable cellular cultures for the preparation of viral and control antigens. Antigens are applicable for RIA and for ELISA examinations of blood sera of infected and vaccinated pigs. The advantages are described of the RIA and ELISA methods as compared with the virus neutralization test.

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

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    Lanzillo R

    2014-10-01

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

  14. Performance characteristics of a combined hepatitis C virus core antigen and anti–hepatitis C virus antibody test in different patient groups

    Directory of Open Access Journals (Sweden)

    Jeng-Fu Yang

    2011-07-01

    Full Text Available We evaluated the performance of a hepatitis C virus (HCV antigen/antibody combination test [Murex HCV Antigen/Antibody Combination Test (Murex Ag/Ab test] by comparing it with the current third-generation HCV antibody enzyme immunoassay (anti-HCV. A total of 403 serum samples were consecutively collected from four patient groups: healthy controls (n=100; HCV-infected patients (HCV group, n=102; Human immunodeficiency virus (HIV/HCV-infected patients (HIV/HCV group, n=100; and patients with uremia (uremia group, n=101. Performances were evaluated for the Murex Ag/Ab, anti-HCV, and HCV RNA in the HIV/HCV and uremia patient groups. In the HCV group, all 102 samples showed concordant positive and negative results for anti-HCV, Murex Ag/Ab, and HCV RNA tests. In the HIV/HCV group, all 100 samples were positive for both anti-HCV and Murex Ag/Ab tests, whereas 88 patients (88% were HCV RNA positive. In the uremia group, 14 (69.0% of the 23 anti-HCV-positive patients were HCV RNA positive, whereas 14 (77.8% of the 18 Murex Ag/Ab–positive patients were HCV RNA positive. None of anti-HCV-negative or Murex Ag/Ab–negative patients were HCV RNA positive. Based on the HCV RNA assay, the sensitivities for both anti-HCV and Murex Ag/Ab assays were 100%, whereas the specificities of these two assays were 89.7% and 95.4%, respectively. With good sensitivity and specificity, the Murex Ag/Ab assay could be a useful alternative diagnostic tool, especially in immunocompromised populations, such as patients with uremia or those infected with HIV.

  15. Polyclonal and monoclonal antibodies specific for the six-helix bundle of the human respiratory syncytial virus fusion glycoprotein as probes of the protein post-fusion conformation

    International Nuclear Information System (INIS)

    Palomo, Concepción; Mas, Vicente; Vázquez, Mónica; Cano, Olga; Luque, Daniel; Terrón, María C.; Calder, Lesley J.; Melero, José A.

    2014-01-01

    Human respiratory syncytial virus (hRSV) has two major surface glycoproteins (G and F) anchored in the lipid envelope. Membrane fusion promoted by hRSV F occurs via refolding from a pre-fusion form to a highly stable post-fusion state involving large conformational changes of the F trimer. One of these changes results in assembly of two heptad repeat sequences (HRA and HRB) into a six-helix bundle (6HB) motif. To assist in distinguishing pre- and post-fusion conformations of hRSV F , we have prepared polyclonal (α-6HB) and monoclonal (R145) rabbit antibodies specific for the 6HB. Among other applications, these antibodies were used to explore the requirements of 6HB formation by isolated protein segments or peptides and by truncated mutants of the F protein. Site-directed mutagenesis and electron microscopy located the R145 epitope in the post-fusion hRSV F at a site distantly located from previously mapped epitopes, extending the repertoire of antibodies that can decorate the F molecule. - Highlights: • Antibodies specific for post-fusion respiratory syncytial virus fusion protein are described. • Polyclonal antibodies were obtained in rabbit inoculated with chimeric heptad repeats. • Antibody binding required assembly of a six-helix bundle in the post-fusion protein. • A monoclonal antibody with similar structural requirements is also described. • Binding of this antibody to the post-fusion protein was visualized by electron microscopy

  16. Polyclonal and monoclonal antibodies specific for the six-helix bundle of the human respiratory syncytial virus fusion glycoprotein as probes of the protein post-fusion conformation

    Energy Technology Data Exchange (ETDEWEB)

    Palomo, Concepción; Mas, Vicente; Vázquez, Mónica; Cano, Olga [Unidad de Biología Viral, Centro Nacional de Microbiología, Madrid (Spain); CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid (Spain); Luque, Daniel; Terrón, María C. [Unidad de Microscopía Electrónica y Confocal, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid (Spain); Calder, Lesley J. [National Institute for Medical Research, MRC, Mill Hill, London NW7 1AA (United Kingdom); Melero, José A., E-mail: jmelero@isciii.es [Unidad de Biología Viral, Centro Nacional de Microbiología, Madrid (Spain); CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid (Spain)

    2014-07-15

    Human respiratory syncytial virus (hRSV) has two major surface glycoproteins (G and F) anchored in the lipid envelope. Membrane fusion promoted by hRSV{sub F} occurs via refolding from a pre-fusion form to a highly stable post-fusion state involving large conformational changes of the F trimer. One of these changes results in assembly of two heptad repeat sequences (HRA and HRB) into a six-helix bundle (6HB) motif. To assist in distinguishing pre- and post-fusion conformations of hRSV{sub F}, we have prepared polyclonal (α-6HB) and monoclonal (R145) rabbit antibodies specific for the 6HB. Among other applications, these antibodies were used to explore the requirements of 6HB formation by isolated protein segments or peptides and by truncated mutants of the F protein. Site-directed mutagenesis and electron microscopy located the R145 epitope in the post-fusion hRSV{sub F} at a site distantly located from previously mapped epitopes, extending the repertoire of antibodies that can decorate the F molecule. - Highlights: • Antibodies specific for post-fusion respiratory syncytial virus fusion protein are described. • Polyclonal antibodies were obtained in rabbit inoculated with chimeric heptad repeats. • Antibody binding required assembly of a six-helix bundle in the post-fusion protein. • A monoclonal antibody with similar structural requirements is also described. • Binding of this antibody to the post-fusion protein was visualized by electron microscopy.

  17. Comparison of Bovine coronavirus-specific and Bovine respiratory syncytial virus-specific antibodies in serum versus milk samples detected by enzyme-linked immunosorbent assay.

    Science.gov (United States)

    Ohlson, Anna; Blanco-Penedo, Isabel; Fall, Nils

    2014-01-01

    Bovine coronavirus (BCV; Betacoronavirus 1) and Bovine respiratory syncytial virus (BRSV) are significant causes of enteric and respiratory disease in beef and dairy cattle throughout the world. Indirect enzyme-linked immunosorbent assays are widely used to detect serum antibodies for herd monitoring and prevalence studies. In dairy herds, milk is more readily collected than serum. Hence, in order to investigate the test agreement between serum and milk, both serum and milk samples from 105 cows in 27 dairy herds were analyzed in parallel for presence of immunoglobulin G antibodies to BCV and BRSV. The Bland-Altman analyses of data demonstrated good agreement between serum and milk antibody titers for both viruses. The results indicate milk samples are sufficient for surveillance of antibodies to BCV and BRSV.

  18. Evidence of dengue virus transmission and factors associated with the presence of anti-dengue virus antibodies in humans in three major towns in Cameroon.

    Science.gov (United States)

    Demanou, Maurice; Pouillot, Régis; Grandadam, Marc; Boisier, Pascal; Kamgang, Basile; Hervé, Jean Pierre; Rogier, Christophe; Rousset, Dominique; Paupy, Christophe

    2014-07-01

    Dengue is not well documented in Africa. In Cameroon, data are scarce, but dengue infection has been confirmed in humans. We conducted a study to document risk factors associated with anti-dengue virus Immunoglobulin G seropositivity in humans in three major towns in Cameroon. A cross sectional survey was conducted in Douala, Garoua and Yaounde, using a random cluster sampling design. Participants underwent a standardized interview and were blood sampled. Environmental and housing characteristics were recorded. Randomized houses were prospected to record all water containers, and immature stages of Aedes mosquitoes were collected. Sera were screened for anti-dengue virus IgG and IgM antibodies. Risk factors of seropositivity were tested using logistic regression methods with random effects. Anti-dengue IgG were found from 61.4% of sera in Douala (n = 699), 24.2% in Garoua (n = 728) and 9.8% in Yaounde (n = 603). IgM were found from 0.3% of Douala samples, 0.1% of Garoua samples and 0.0% of Yaounde samples. Seroneutralization on randomly selected IgG positive sera showed that 72% (n = 100) in Douala, 80% (n = 94) in Garoua and 77% (n = 66) in Yaounde had antibodies specific for dengue virus serotype 2 (DENV-2). Age, temporary house walls materials, having water-storage containers, old tires or toilets in the yard, having no TV, having no air conditioning and having travelled at least once outside the city were independently associated with anti-dengue IgG positivity in Douala. Age, having uncovered water containers, having no TV, not being born in Garoua and not breeding pigs were significant risk factors in Garoua. Recent history of malaria, having banana trees and stagnant water in the yard were independent risk factors in Yaounde. In this survey, most identified risk factors of dengue were related to housing conditions. Poverty and underdevelopment are central to the dengue epidemiology in Cameroon.

  19. A human monoclonal antibody derived from a vaccinated volunteer recognizes heterosubtypically a novel epitope on the hemagglutinin globular head of H1 and H9 influenza A viruses

    International Nuclear Information System (INIS)

    Boonsathorn, Naphatsawan; Panthong, Sumolrat; Koksunan, Sarawut; Chittaganpitch, Malinee; Phuygun, Siripaporn; Waicharoen, Sunthareeya; Prachasupap, Apichai; Sasaki, Tadahiro; Kubota-Koketsu, Ritsuko; Yasugi, Mayo; Ono, Ken-ichiro; Arai, Yasuha

    2014-01-01

    Highlights: • A human monoclonal antibody against influenza virus was produced from a volunteer. • The antibody was generated from the PBMCs of the volunteer using the fusion method. • The antibody neutralized heterosubtypically group 1 influenza A viruses (H1 and H9). • The antibody targeted a novel epitope in globular head region of the hemagglutinin. • Sequences of the identified epitope are highly conserved among H1 and H9 subtypes. - Abstract: Most neutralizing antibodies elicited during influenza virus infection or by vaccination have a narrow spectrum because they usually target variable epitopes in the globular head region of hemagglutinin (HA). In this study, we describe a human monoclonal antibody (HuMAb), 5D7, that was prepared from the peripheral blood lymphocytes of a vaccinated volunteer using the fusion method. The HuMAb heterosubtypically neutralizes group 1 influenza A viruses, including seasonal H1N1, 2009 pandemic H1N1 (H1N1pdm) and avian H9N2, with a strong hemagglutinin inhibition activity. Selection of an escape mutant showed that the HuMAb targets a novel conformational epitope that is located in the HA head region but is distinct from the receptor binding site. Furthermore, Phe114Ile substitution in the epitope made the HA unrecognizable by the HuMAb. Amino acid residues in the predicted epitope region are also highly conserved in the HAs of H1N1 and H9N2. The HuMAb reported here may be a potential candidate for the development of therapeutic/prophylactic antibodies against H1 and H9 influenza viruses

  20. A human monoclonal antibody derived from a vaccinated volunteer recognizes heterosubtypically a novel epitope on the hemagglutinin globular head of H1 and H9 influenza A viruses

    Energy Technology Data Exchange (ETDEWEB)

    Boonsathorn, Naphatsawan; Panthong, Sumolrat [Medical Life Sciences Institute, Department of Medical Sciences, Ministry of Public Health, Muang, Nonthaburi (Thailand); Japan Science and Technology Agency/Japan International Cooperation Agency, Science and Technology Research Partnership for Sustainable Development (JST/JICA, SATREPS), Tokyo (Japan); Koksunan, Sarawut [Medical Life Sciences Institute, Department of Medical Sciences, Ministry of Public Health, Muang, Nonthaburi (Thailand); Chittaganpitch, Malinee; Phuygun, Siripaporn; Waicharoen, Sunthareeya [National Institute of Health, Department of Medical Sciences, Ministry of Public Health, Muang, Nonthaburi (Thailand); Prachasupap, Apichai [Medical Life Sciences Institute, Department of Medical Sciences, Ministry of Public Health, Muang, Nonthaburi (Thailand); Japan Science and Technology Agency/Japan International Cooperation Agency, Science and Technology Research Partnership for Sustainable Development (JST/JICA, SATREPS), Tokyo (Japan); Sasaki, Tadahiro [Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Japan Science and Technology Agency/Japan International Cooperation Agency, Science and Technology Research Partnership for Sustainable Development (JST/JICA, SATREPS), Tokyo (Japan); Kubota-Koketsu, Ritsuko [Kanonji Institute, The Research Foundation for Microbial Diseases of Osaka University, Kanonji, Kagawa (Japan); Yasugi, Mayo [Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka (Japan); Ono, Ken-ichiro [Ina