USDA-ARS?s Scientific Manuscript database
The serum virus neutralization (SVN) assay is a serological test to detect the presence and magnitude of functional systemic antibodies that prevent infectivity of a virus. The SVN assay is a highly sensitive and specific test that may be applied to influenza A viruses (IAV) in swine to measure the ...
Low specificity of 2 tetanus rapid tests in Cambodia.
Schlumberger, M; Yvonnet, B; Lesage, G; Tep, B
2015-01-01
Rapid testing for tetanus on serum or blood allows for an immediate evaluation of individual protection against tetanus in developed countries, using a "single step" immunochromatographic technique using tetanus toxoid. The specificity of these tests, compared to the reference method for tetanus, mouse serum neutralization testing, has however never been assessed in these countries, due to the difficulty to perform serum neutralization titration in mice, because of animal testing bioethical regulations. A collection of sera from adult volunteers in Cambodia, living in rural environment, was tested for tetanus antibodies by ELISA in France, and by mouse serum neutralization in Vietnam. This allowed estimating the sensitivity and specificity of 2 rapid tetanus tests, available on the market: TQS™ and Tetanotop™. The sensitivity of these tests was adequate, compared to mice serum neutralization test, for a test threshold of 0.01 IU/mL, (100% for TQS™, 91% for Tetanotop™), but their specificity was very low (1% for TQS™ and 13% for Tetanotop™). The results prove that these rapid tests for the assessment of individual protection against tetanus should not be used in the adult rural Cambodian population. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
Sakata, H; Hishiyama, M; Sugiura, A
1984-01-01
Mumps-specific antibody levels before and after vaccination with live mumps vaccines were determined by enzyme-linked immunosorbent assay (ELISA) and neutralization tests. A correlation was found between neutralization titers and optical density in ELISA. However, postvaccination sera from some vaccinees who failed to seroconvert by neutralization contained significant levels of mumps-specific antibody detectable by ELISA. In some of these serum specimens, the antibody directed to the F polypeptide of mumps virus was predominant. Most sera positive in ELISA neutralized mumps virus upon the addition of fresh guinea pig serum to the virus-serum mixture. Images PMID:6361060
DOE Office of Scientific and Technical Information (OSTI.GOV)
Saunders, G.C.
1977-01-01
A rapid enzyme-labeled antibody (ELA) microtechnique for the screening of swine for hog cholera antibodies was developed and evaluated with a blind study, using a 640-sample hog cholera serum bank. The total time to run a group of 22 samples was approximately 1 hour. The ELA test results correlated >99% with hog cholera serum-neutralization test results on the same serums. Test results also indicated that the ELA test shares with the hog cholera serum-neutralization test the problem of cross reactions between the antibodies of hog cholera and bovine viral diarrhea.
A single, continuous metric to define tiered serum neutralization potency against HIV
Hraber, Peter Thomas; Korber, Bette Tina Marie; Wagh, Kshitij; ...
2018-01-19
HIV-1 Envelope (Env) variants are grouped into tiers by their neutralization-sensitivity phenotype. This helped to recognize that tier 1 neutralization responses can be elicited readily, but do not protect against new infections. Tier 3 viruses are the least sensitive to neutralization. Because most circulating viruses are tier 2, vaccines that elicit neutralization responses against them are needed. While tier classification is widely used for viruses, a way to rate serum or antibody neutralization responses in comparable terms is needed. Logistic regression of neutralization outcomes summarizes serum or antibody potency on a continuous, tier-like scale. It also tests significance of themore » neutralization score, to indicate cases where serum response does not depend on virus tiers. The method can standardize results from different virus panels, and could lead to high-throughput assays, which evaluate a single serum dilution, rather than a dilution series, for more efficient use of limited resources to screen samples from vaccinees.« less
A single, continuous metric to define tiered serum neutralization potency against HIV
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hraber, Peter Thomas; Korber, Bette Tina Marie; Wagh, Kshitij
HIV-1 Envelope (Env) variants are grouped into tiers by their neutralization-sensitivity phenotype. This helped to recognize that tier 1 neutralization responses can be elicited readily, but do not protect against new infections. Tier 3 viruses are the least sensitive to neutralization. Because most circulating viruses are tier 2, vaccines that elicit neutralization responses against them are needed. While tier classification is widely used for viruses, a way to rate serum or antibody neutralization responses in comparable terms is needed. Logistic regression of neutralization outcomes summarizes serum or antibody potency on a continuous, tier-like scale. It also tests significance of themore » neutralization score, to indicate cases where serum response does not depend on virus tiers. The method can standardize results from different virus panels, and could lead to high-throughput assays, which evaluate a single serum dilution, rather than a dilution series, for more efficient use of limited resources to screen samples from vaccinees.« less
Powassan virus infection in snowshoe hares (Lepus americanus).
Zarnke, R L; Yuill, T M
1981-04-01
Sera from snowshoe hares (Lepus americanus) trapped near Rochester, Alberta, Canada were tested for Powassan virus antibody by the constant virus/serum dilution neutralization test. Of 1264 serum samples tested, 137 had an antibody titer of at least 1:4 for Powassan virus. Ten hares were inoculated with Powassan virus in the laboratory. Viremia lasted 4-5 days and ceased with the appearance of Powassan antibody in the serum. Neutralizing antibody reached a peak titer of 1:119 on day 15 post-inoculation and was still detectable 13 months post-inoculation.
A novel, colorimetric neutralization assay for measuring antibodies to influenza viruses.
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.
Trask, James D.; Blake, Francis G.
1924-01-01
A series of observations on the blood of patients acutely ill with scarlet fever has shown that a toxic substance can be demonstrated in the serum by means of intracutaneous injections of the serum in persons who have not had scarlet fever and whose serums fail to blanch the rash in scarlet fever. The reaction caused by this substance consists of a bright red local erythema, varying from 20 to 70 mm. in diameter, of 1 to 4 days duration. The severer reactions are moderately indurated and tender, and are followed bypigmentation and desquamation. Control injections in persons whose serums blanch the rash in scarlet fever cause no reaction. The toxic substance is not neutralized by mixture with a human serum which gives a negative blanching test but is readily neutralized by a human serum which gives a positive blanching test. It is not neutralized by normal horse serum, but is completely neutralized by Dochez's scarlatinal antistreptococcic serum. In a limited number of observations on the urine of patients with scarlet fever a similar toxic substance has been found in two out of five cases studied. Since the toxic substance described appears to resemble the toxic substance found in the filtrates of scarlatinal hemolytic streptococcus cultures by Dick and Dick and since it is neutralized not only by a blanching human serum but also by Dochez's scarlatinal antistreptococcic horse serum, the experiments reported support the conception that scarlet fever is a local infection of the throat by a particular type of Streptococcus hæmolyticus capable of producing a toxin which is absorbed and is the cause of the general manifestations of the disease. PMID:19868926
Development of a High-Content Orthopoxvirus Infectivity and Neutralization Assays
Gates, Irina; Olson, Victoria; Smith, Scott; Patel, Nishi; Damon, Inger; Karem, Kevin
2015-01-01
Currently, a number of assays measure Orthopoxvirus neutralization with serum from individuals, vaccinated against smallpox. In addition to the traditional plaque reduction neutralization test (PRNT), newer higher throughput assays are based on neutralization of recombinant vaccinia virus, expressing reporter genes such as β-galactosidase or green fluorescent protein. These methods could not be used to evaluate neutralization of variola virus, since genetic manipulations of this virus are prohibited by international agreements. Currently, PRNT is the assay of choice to measure neutralization of variola virus. However, PRNT assays are time consuming, labor intensive, and require considerable volume of serum sample for testing. Here, we describe the development of a high-throughput, cell-based imaging assay that can be used to measure neutralization, and characterize replication kinetics of various Orthopoxviruses, including variola, vaccinia, monkeypox, and cowpox. PMID:26426117
Feng, Yan; Lu, Yi-yu; Yan, Ju-ying; Jiang, Xiao-hui; Shi, Wen; Xu, Chang-ping; Li, Zhen
2007-11-01
To explore the neutralization capacities of different types of human serum to measles virus epidemic strains and vaccine strain. Neutralization antibody (NT) to Shanghai 191 and measles virus isolates in 2005 were tested using acute and convalescent serum samples from diagnosed measles patients, children serum samples collected before and after vaccination and serum samples of migrant residents, from 3 different regions. Additionally, animal immune serum referring to vaccine strain and 3 epidemic strains were prepared and used to undergo crossing neutralization test with corresponding strains mentioned-above. Antigenic ratios were calculated. GMT value of NT of after-immune serum to vaccine strains was 50.82,1.86 times higher than that to MVi/ZJ/05/7 (GMT was 27.35), whereas GMT value of convalescent serum to MVi/ZJ/05/7 (GMT was 386.95) was obviously higher than that to vaccine strain (GMT was 1:151.83),and GMT value of migrant residents' serum in 3 regions to MVi/ZJ/05/7 were 2.22-4.17 times lower than that to vaccine strain. Meanwhile,the antigenic ratios between MVi/ZJ/ 99/1, MVi/ZJ/04/1, MVi/ZJ/05/7 and vaccine strain were found to be 4.28,5.24 and 5.66 respectively. Additionally,low NT titers to vaccine strain were found in patients' acute sera and GMT value was over 1:4. There were obvious differences on neutralization antibody of different types of serum to measles vaccine strain and epidemic strains which indicating the antigenic diversity of epidemic strains had influenced the protective effectiveness of vaccine antibody to epidemic strains. It was of significance to carry on research projects on the antigenic diversity and effectiveness of measles vaccine.
Vaidya, Sunil R; Dvivedi, Garima M; Jadhav, Santoshkumar M
2016-01-01
The reports from the countries where mumps vaccine is given as routine immunization suggest differences in mumps virus neutralizing antibody titres when tested with vaccine and wild type viruses. Such reports are unavailable from countries like India where mumps vaccine is not included in routine immunization. We, therefore, undertook this study to understand the cross-neutralization activity of Indian mumps viruses. By using commercial mumps IgG enzyme immunoassay (EIA) and a rapid focus reduction neutralization test (FRNT), a panel of serum samples was tested. The panel consisted of 14 acute and 14 convalescent serum samples collected during a mumps outbreak and 18 archived serum samples. Two wild types (genotypes C and G) and Leningrad-Zagreb vaccine strain (genotype N) were used for the challenge experiments and FRNT titres were determined and further compared. The HN protein sequence of three mumps viruses was analyzed for the presence of key epitopes. All serum samples effectively neutralized mumps virus wild types and a vaccine strain. However, significantly lower FRNT titres were noted to wild types than to vaccine strain (P<0.05). The comparison between EIA and FRNT results revealed 95.6 per cent agreement. No amino acid changes were seen in the epitopes in the Indian wild type strains. All potential N-linked glycosylation sites were observed in Indian strains. Good cross-neutralization activity was observed for three mumps virus strains, however, higher level of FRNT titres was detected for mumps virus vaccine strain compared to Indian wild type isolates.
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.
Vaidya, Sunil R.; Dvivedi, Garima M.; Jadhav, Santoshkumar M.
2016-01-01
Background & objectives: The reports from the countries where mumps vaccine is given as routine immunization suggest differences in mumps virus neutralizing antibody titres when tested with vaccine and wild type viruses. Such reports are unavailable from countries like India where mumps vaccine is not included in routine immunization. We, therefore, undertook this study to understand the cross-neutralization activity of Indian mumps viruses. Methods: By using commercial mumps IgG enzyme immunoassay (EIA) and a rapid focus reduction neutralization test (FRNT), a panel of serum samples was tested. The panel consisted of 14 acute and 14 convalescent serum samples collected during a mumps outbreak and 18 archived serum samples. Two wild types (genotypes C and G) and Leningrad-Zagreb vaccine strain (genotype N) were used for the challenge experiments and FRNT titres were determined and further compared. The HN protein sequence of three mumps viruses was analyzed for the presence of key epitopes. Results: All serum samples effectively neutralized mumps virus wild types and a vaccine strain. However, significantly lower FRNT titres were noted to wild types than to vaccine strain (P<0.05). The comparison between EIA and FRNT results revealed 95.6 per cent agreement. No amino acid changes were seen in the epitopes in the Indian wild type strains. All potential N-linked glycosylation sites were observed in Indian strains. Interpretation & conclusions: Good cross-neutralization activity was observed for three mumps virus strains, however, higher level of FRNT titres was detected for mumps virus vaccine strain compared to Indian wild type isolates. PMID:26997012
Vora, Neil M; Orciari, Lillian A; Bertumen, J Bradford; Damon, Inger; Ellison, James A; Fowler, Vance G; Franka, Richard; Petersen, Brett W; Satheshkumar, P S; Schexnayder, Stephen M; Smith, Todd G; Wallace, Ryan M; Weinstein, Susan; Williams, Carl; Yager, Pamela; Niezgoda, Michael
2018-02-09
Rabies is an acute encephalitis that is nearly always fatal. It is caused by infection with viruses of the genus Lyssavirus, the most common of which is Rabies lyssavirus. The Council of State and Territorial Epidemiologists (CSTE) defines a confirmed human rabies case as an illness compatible with rabies that meets at least one of five different laboratory criteria.* Four of these criteria do not depend on the patient's rabies vaccination status; however, the remaining criterion, "identification of Lyssavirus-specific antibody (i.e. by indirect fluorescent antibody…test or complete [Rabies lyssavirus] neutralization at 1:5 dilution) in the serum," is only considered diagnostic in unvaccinated patients. Lyssavirus-specific antibodies include Rabies lyssavirus-specific binding immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies and Rabies lyssavirus neutralizing antibodies (RLNAs). This report describes six patients who were tested for rabies by CDC and who met CSTE criteria for confirmed human rabies because they had illnesses compatible with rabies, had not been vaccinated for rabies, and were found to have serum RLNAs (with complete Rabies lyssavirus neutralization at a serum dilution of 1:5). An additional four patients are described who were tested for rabies by CDC who were found to have serum RLNAs (with incomplete Rabies lyssavirus neutralization at a serum dilution of 1:5) despite having not been vaccinated for rabies. None of these 10 patients received a rabies diagnosis; rather, they were considered to have been passively immunized against rabies through recent receipt of intravenous immune globulin (IVIG). Serum RLNA test results should be interpreted with caution in patients who have not been vaccinated against rabies but who have recently received IVIG.
Timiryasova, Tatyana M.; Bonaparte, Matthew I.; Luo, Ping; Zedar, Rebecca; Hu, Branda T.; Hildreth, Stephen W.
2013-01-01
A dengue plaque reduction neutralization test (PRNT) to measure dengue serotype–specific neutralizing antibodies for all four virus serotypes was developed, optimized, and validated in accordance with guidelines for validation of bioanalytical test methods using human serum samples from dengue-infected persons and persons receiving a dengue vaccine candidate. Production and characterization of dengue challenge viruses used in the assay was standardized. Once virus stocks were characterized, the dengue PRNT50 for each of the four serotypes was optimized according to a factorial design of experiments approach for critical test parameters, including days of cell seeding before testing, percentage of overlay carboxymethylcellulose medium, and days of incubation post-infection to generate a robust assay. The PRNT50 was then validated and demonstrated to be suitable to detect and measure dengue serotype-specific neutralizing antibodies in human serum samples with acceptable intra-assay and inter-assay precision, accuracy/dilutability, specificity, and with a lower limit of quantitation of 10. PMID:23458954
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Xinsheng, E-mail: xzhang@iavi.org; Molecular and Cellular Biology Program, State University of New York, Brooklyn, NY; Wallace, Olivia L.
Serum was analyzed from 146 healthy adult volunteers in eastern Africa to evaluate measles virus (MV) and canine distemper virus (CDV) neutralizing antibody (nAb) prevalence and potency. MV plaque reduction neutralization test (PRNT) results indicated that all sera were positive for MV nAbs. Furthermore, the 50% neutralizing dose (ND50) for the majority of sera corresponded to antibody titers induced by MV vaccination. CDV nAbs titers were low and generally were detected in sera with high MV nAb titers. A mutant CDV was generated that was less sensitive to neutralization by human serum. The mutant virus genome had 10 nucleotide substitutions,more » which coded for single amino acid substitutions in the fusion (F) and hemagglutinin (H) glycoproteins and two substitutions in the large polymerase (L) protein. The H substitution occurred in a conserved region involved in receptor interactions among morbilliviruses, implying that this region is a target for cross-reactive neutralizing antibodies. - Highlights: • Screened 146 serum samples for measles virus (MV) and canine distemper virus (CDV) neutralizing antibody (nAb). • MV nAb is prevalent in the sera. • CDV neutralizing activity is generally low or absent and when detected it is present in sera with high MV nAb titers. • A neutralization-resistant CDV mutant was isolated using human serum selection. • A mutation was identified in the receptor-binding region of CDV hemagglutinin protein that confers the neutralization resistance.« less
Seroimmunity to polioviruses in U.S. Army recruits.
Burke, D S; Gaydos, J C; Hodder, R A; Bancroft, W H
1979-02-01
Titers of neutralizing antibody to poliovirus types 1, 2, and 3 were determined for serum specimens obtained from 268 U.S. Army recruits. Among those tested, 20.9% lacked neutralizing antibody to one or more types of poliovirus, and 1.1% lacked antibody to all three types. An analysis of demographic data showed that age of less than 18 years, schooling for less than 10 years, and residence in the northeastern United States were associated with higher percentages of recruits lacking neutralizing antibodies to polioviruses in serum.
Moeschler, Sarah; Locher, Samira; Conzelmann, Karl-Klaus; Krämer, Beate; Zimmer, Gert
2016-01-01
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. PMID:27649230
9 CFR 113.311 - Bovine Virus Diarrhea Vaccine.
Code of Federal Regulations, 2010 CFR
2010-01-01
... virus diarrhea post-challenge; or both, the Master Seed Virus is unsatisfactory. (6) A sequential test... virus diarrhea susceptible calves shall be used as test animals (20 vaccinates and five controls). Blood... serum dilution in a varying serum-constant virus neutralization test with less than 500 TCID50 of bovine...
Jemima, Ebenezer Angel; Manoharan, Seeralan; Kumanan, Kathaperumal
2014-08-01
The measurement of neutralizing antibodies induced by the glycoprotein of rabies virus is indispensable for assessing the level of neutralizing antibodies in animals or humans. A rapid fluorescent focus inhibition test (RFFIT) has been approved by WHO and is the most widely used method to measure the virus-neutralizing antibody content in serum, but a rapid test system would be of great value to screen large numbers of serum samples. To develop and evaluate a latex agglutination test (LAT) for measuring rabies virus antibodies, a recombinant glycoprotein was expressed in an insect cell system and purified, and the protein was coated onto latex beads at concentrations of 0.1, 0.25, 0.5, 0.75, and 1 mg/ml to find out the optimal concentration for coating latex beads. It was found that 0.5 mg/ml of recombinant protein was optimal for coating latex beads, and this concentration was used to sensitize the latex beads for screening of dog serum samples. Grading of LAT results was done with standard reference serum with known antibody titers. A total of 228 serum samples were tested, out of which 145 samples were positive by both RFFIT and LAT, and the specificity was found to be 100 %. In RFFIT, 151 samples were positive, the sensitivity was found to be 96.03 %, and the accuracy/concordance was found to be 97.39 %. A rapid field test-a latex agglutination test (LAT)-was developed and evaluated for rabies virus antibody assessment using recombinant glycoprotein of rabies virus expressed in an insect cell system.
Optimizing Cationic and Neutral Lipids for Efficient Gene Delivery at High Serum Content
Majzoub, Ramsey N.; Hwu, Yeu-kuang; Liang, Keng S.; Leal, Cecília; Safinya, Cyrus R.
2014-01-01
Background Cationic liposome (CL)-DNA complexes are promising gene delivery vectors with potential applications in gene therapy. A key challenge in creating CL-DNA complexes for applications is that their transfection efficiency (TE) is adversely affected by serum. In particular, little is known about the effects of high serum contents on TE even though this may provide design guidelines for applications in vivo. Methods We prepared CL-DNA complexes in which we varied the neutral lipid (DOPC, glycerol-monooleate (GMO), cholesterol), the headgroup charge and chemical structure of the cationic lipid, and the ratio of neutral to cationic lipid; we then measured the TE of these complexes as a function of serum content and assessed their cytotoxicity. We tested selected formulations in two human cancer cell lines (M21/melanoma and PC-3/prostate cancer). Results In the absence of serum, all CL-DNA complexes of custom-synthesized multivalent lipids show high TE. Certain combinations of multivalent lipids and neutral lipids, such as MVL5(5+)/GMO-DNA complexes or complexes based on the dendritic-headgroup lipid TMVLG3(8+) exhibited high TE both in the absence and presence of serum. Although their TE still dropped to a small extent in the presence of serum, it reached or surpassed that of benchmark commercial transfection reagents, in particular at high serum content. Conclusions Two-component vectors (one multivalent cationic lipid and one neutral lipid) can rival or surpass benchmark reagents at low and high serum contents (up to 50%, v/v). We suggest guidelines for optimizing the serum resistance of CL-DNA complexes based on a given cationic lipid. PMID:24753287
9 CFR 98.34 - Import permits for poultry semen and animal semen.
Code of Federal Regulations, 2014 CFR
2014-01-01
... associated antigen (VIAA) in serum. (Animals having responses to the AGID test or reacting to the VN test at...). (C) Swine vesicular disease: Virus neutralization test at 1:40 dilution (serums to be tested at FADDL... section have been met. (d) Sheep and goat semen from regions where scrapie exists. Importation of semen of...
9 CFR 98.34 - Import permits for poultry semen and animal semen.
Code of Federal Regulations, 2013 CFR
2013-01-01
... associated antigen (VIAA) in serum. (Animals having responses to the AGID test or reacting to the VN test at...). (C) Swine vesicular disease: Virus neutralization test at 1:40 dilution (serums to be tested at FADDL... section have been met. (d) Sheep and goat semen from regions where scrapie exists. Importation of semen of...
9 CFR 98.34 - Import permits for poultry semen and animal semen.
Code of Federal Regulations, 2012 CFR
2012-01-01
... associated antigen (VIAA) in serum. (Animals having responses to the AGID test or reacting to the VN test at...). (C) Swine vesicular disease: Virus neutralization test at 1:40 dilution (serums to be tested at FADDL... section have been met. (d) Sheep and goat semen from regions where scrapie exists. Importation of semen of...
9 CFR 113.309 - Bovine Parainfluenza3 Vaccine.
Code of Federal Regulations, 2010 CFR
2010-01-01
... develop antibody titers of 1:32 or greater by day 6 ±2 days post-challenge. (8) A sequential test... parainfluenza, susceptible calves shall be used as test animals (20 vaccinates and five controls). Blood samples... negative at a 1:2 final serum dilution in a varying serum constant virus neutralization test with less than...
9 CFR 113.309 - Bovine Parainfluenza3 Vaccine.
Code of Federal Regulations, 2012 CFR
2012-01-01
... develop antibody titers of 1:32 or greater by day 6 ±2 days post-challenge. (8) A sequential test... parainfluenza, susceptible calves shall be used as test animals (20 vaccinates and five controls). Blood samples... negative at a 1:2 final serum dilution in a varying serum constant virus neutralization test with less than...
9 CFR 113.300 - General requirements for live virus vaccines.
Code of Federal Regulations, 2010 CFR
2010-01-01
... control cells shall remain free of such fluorescence. (2) Serum neutralization test. The serum... fungi in accordance with the test provided in § 113.27. (2) Mycoplasma. Final container samples of... inoculated cells and uninoculated control cells. Cells shall be stained with fluorochrome conjugated specific...
Cabon, J; Louboutin, L; Castric, J; Bergmann, S; Bovo, G; Matras, M; Haenen, O; Olesen, N J; Morin, T
2017-05-01
Cyprinid herpesvirus 3 (CyHV-3) is the aetiological agent of a serious infective, notifiable disease affecting common carp and varieties. In survivors, infection is generally characterized by a subclinical latency phase with restricted viral replication. The CyHV-3 genome is difficult to detect in such carrier fish that represent a potential source of dissemination if viral reactivation occurs. In this study, the analytical and diagnostic performance of an alternative serum neutralization (SN) method based on the detection of CyHV-3-specific antibodies was assessed using 151 serum or plasma samples from healthy and naturally or experimentally CyHV-3-infected carp. French CyHV-3 isolate 07/108b was neutralized efficiently by sera from carp infected with European, American and Taiwanese CyHV-3 isolates, but no neutralization was observed using sera specific to other aquatic herpesviruses. Diagnostic sensitivity, diagnostic specificity and repeatability of 95.9%, 99.0% and 99.3%, respectively, were obtained, as well as a compliance rate of 89.9% in reproducibility testing. Neutralizing antibodies were steadily detected in infected carp subjected to restrictive or permissive temperature variations over more than 25 months post-infection. The results suggest that this non-lethal diagnostic test could be used in the future to improve the epidemiological surveillance and control of CyHV-3 disease. © 2016 John Wiley & Sons Ltd.
Shenoy, P A; Nipate, S S; Sonpetkar, J M; Salvi, N C; Waghmare, A B; Chaudhari, P D
2014-01-15
Piper longum L. fruits have been traditionally used against snakebites in north-eastern and southern region of India. The aim of the study was to assess the production of antibody response against Russell's viper venom in mice after prophylactic immunization with ethanolic extract of fruits of Piper longum L. and piperine. The mice sera were tested for the presence of antibodies against Russell's viper venom by in vitro lethality neutralization assay and in vivo lethality neutralization assay. Polyvalent anti-snake venom serum (antivenom) manufactured by Haffkine Bio-Pharmaceutical Corporation Ltd. was used as standard. Further confirmation of presence of antibodies against the venom in sera of mice immunized with PLE and piperine was done using indirect enzyme-linked immunosorbent assay (ELISA) and double immunodiffusion test. Treatment with PLE-treated mice serum and piperine-treated mice serum was found to inhibit the lethal action of venom both in the in vitro lethality neutralization assay and in vivo lethality neutralization assay. ELISA testing indicated that there were significantly high (p<0.01) levels of cross reactions between the PLE and piperine treated mice serum and the venom antigens. In double immunodiffusion test, a white band was observed between the two wells of antigen and antibodies for both the PLE-treated and piperine-treated mice serum. Thus it can be concluded that immunization with ethanolic extract of fruits of Piper longum and piperine produced a high titre antibody response against Russell's viper venom in mice. The antibodies against PLE and piperine could be useful in antivenom therapy of Russell's viper bites. PLE and piperine may also have a potential interest in view of the development of antivenom formulations used as antidote against snake bites. Copyright © 2013 Elsevier GmbH. All rights reserved.
Serologic Evidence of Lyssavirus Infection in Bats, Cambodia
Molia, Sophie; Audry, Laurent; Hout, Sotheara; Ngin, Sopheak; Walston, Joe; Bourhy, Hervé
2004-01-01
In Cambodia, 1,303 bats of 16 species were tested for lyssavirus. No lyssavirus nucleocapsid was detected in 1,283 brains tested by immunofluorescence assay. Antibodies against lyssaviruses were detected by enzyme-linked immunosorbent assay in 144 (14.7%) of 981 serum samples. Thirty of 187 serum samples contained neutralizing antibodies against different lyssaviruses. PMID:15663870
Lack of Durable Cross-Neutralizing Antibodies Against Zika Virus from Dengue Virus Infection.
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.
Lack of Durable Cross-Neutralizing Antibodies Against Zika Virus from Dengue Virus Infection
McGowan, Eileen; Jadi, Ramesh; Young, Ellen; Lopez, Cesar A.; Baric, Ralph S.; Lazear, Helen M.
2017-01-01
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. PMID:28418292
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.
In vivo emergence of HIV-1 highly sensitive to neutralizing antibodies.
Aasa-Chapman, Marlén M I; Cheney, Kelly M; Hué, Stéphane; Forsman, Anna; O'Farrell, Stephen; Pellegrino, Pierre; Williams, Ian; McKnight, Áine
2011-01-01
The rapid and continual viral escape from neutralizing antibodies is well documented in HIV-1 infection. Here we report in vivo emergence of viruses with heightened sensitivity to neutralizing antibodies, sometimes paralleling the development of neutralization escape. Sequential viral envs were amplified from seven HIV-1 infected men monitored from seroconversion up to 5 years after infection. Env-recombinant infectious molecular clones were generated and tested for coreceptor use, macrophage tropism and neutralization sensitivity to homologous and heterologous serum, soluble CD4 and monoclonal antibodies IgG1b12, 2G12 and 17b. We found that HIV-1 evolves sensitivity to contemporaneous neutralizing antibodies during infection. Neutralization sensitive viruses grow out even when potent autologous neutralizing antibodies are present in patient serum. Increased sensitivity to neutralization was associated with susceptibility of the CD4 binding site or epitopes induced after CD4 binding, and mediated by complex envelope determinants including V3 and V4 residues. The development of neutralization sensitive viruses occurred without clinical progression, coreceptor switch or change in tropism for primary macrophages. We propose that an interplay of selective forces for greater virus replication efficiency without the need to resist neutralizing antibodies in a compartment protected from immune surveillance may explain the temporal course described here for the in vivo emergence of HIV-1 isolates with high sensitivity to neutralizing antibodies.
Murata, Ryo; Hashiguchi, Kazuaki; Yoshii, Kentaro; Kariwa, Hiroaki; Nakajima, Kensuke; Ivanov, Leonid I.; Leonova, Galina N.; Takashima, Ikuo
2011-01-01
West Nile (WN) virus has been spreading geographically to non-endemic areas in various parts of the world. However, little is known about the extent of WN virus infection in Russia. Japanese encephalitis (JE) virus, which is closely related to WN virus, is prevalent throughout East Asia. We evaluated the effectiveness of a focus reduction neutralization test in young chicks inoculated with JE and WN viruses, and conducted a survey of WN infection among wild birds in Far Eastern Russia. Following single virus infection, only neutralizing antibodies specific to the homologous virus were detected in chicks. The neutralization test was then applied to serum samples from 145 wild birds for WN and JE virus. Twenty-one samples were positive for neutralizing antibodies to WN. These results suggest that WN virus is prevalent among wild birds in the Far Eastern region of Russia. PMID:21363987
21 CFR 862.1705 - Triglyceride test system.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Triglyceride test system. 862.1705 Section 862....1705 Triglyceride test system. (a) Identification. A triglyceride test system is a device intended to measure triglyceride (neutral fat) in serum and plasma. Measurements obtained by this device are used in...
9 CFR 113.201 - Canine Distemper Vaccine, Killed Virus.
Code of Federal Regulations, 2010 CFR
2010-01-01
... be established. Vaccine used for this test shall be at the highest passage from the Master Seed and... canine distemper susceptible dogs (20 vaccinates and 5 controls) shall be used as test animals. Blood... distemper to determine susceptibility. A constant virus-varying serum neutralization test in cell culture...
Neutralizing Antibody Response to Booster Vaccination with the 17d Yellow Fever Vaccine
2006-01-18
FY03-28, approved 18 December 2003). 2.2. PRNT Patient sera were tested for neutralizing antibody to yellow fever virus ( YFV ) using a PRNT80 as...described by Man- giafico et al. [16], but modified for use with the Asibi strain of YFV . Briefly, test sera and controls were initially diluted 1:10 in...the 1:10 dilution, in HBSS containing human serum albumin, HEPES, peni- cillin and streptomycin. An equal volume of YFV , calculated to yield
Liu, Ruyu; Rao, Huiying; Wang, Jianghua; Xie, Xingwang; Jiang, Dong; Pan, Xiaoben; Zhao, Ping; Zhang, Henghui; Wei, Lai
2013-01-01
It has been reported that monoclonal antibodies (MAbs) to the E1E2 glycoproteins may have the potential to prevent hepatitis C virus (HCV) infection. The protective epitopes targeted by these MAbs have been mapped to the regionsencompassing amino acids 313–327 and 432–443. In this study, we synthesized these two peptides and tested the reactivity of serum samples from 336 patients, 210 of whichwere from Chronic Hepatitis C (CHC) patients infected with diverse HCV genotypes.The remaining 126 samples were isolated from patients who had spontaneously clearedHCV infection.In the chronic HCV-infected group (CHC group), the prevalence of human serum antibodies reactive to epitopes 313–327 and 432–443was 24.29%(51 of 210) and4.76%(10 of 210),respectively. In thespontaneousclearance group (SC group),the prevalence was 0.79%(1 of 126) and 12.70%(16 of 126), respectively.The positive serum samples that contained antibodies reactive to epitope 313–327 neutralizedHCV pseudoparticles (HCVpp) bearing the envelope glycoproteins of genotypes 1a or 1b and/or 4, but genotypes 2a, 3a, 5 and 6 were not neutralized. The neutralizing activity of these serum samples could not be inhibited by peptide 313–327. Six samples (SC17, SC38, SC86, SC92, CHC75 and CHC198) containing antibodies reactive to epitope 432–443 had cross-genotype neutralizing activities. Theneutralizing activityof SC38, SC86, SC92 and CHC75waspartiallyinhibited by peptide 432–443. However,the neutralizing activity of sample SC17 for genotype 4HCVpp and sample CHC198 for genotype 1b HCVppwere notinhibited by the peptide.This study identifies the neutralizing ability of endogenous anti-HCV antibodies and warrants the exploration of antibodies reactive to epitope432–443as sources for future antibody therapies. PMID:23826163
Serological tests for detecting Rift Valley fever viral antibodies in sheep from the Nile Delta.
Scott, R M; Feinsod, F M; Allam, I H; Ksiazek, T G; Peters, C J; Botros, B A; Darwish, M A
1986-01-01
To determine the accuracy of serological methods in detecting Rift Valley fever (RVF) viral antibodies, we examined serum samples obtained from 418 sheep in the Nile Delta by using five tests. The plaque reduction neutralization test (PRNT) was considered the standard serological method against which the four other tests were compared. Twenty-four serum samples had RVF viral antibodies detected by PRNT. Hemagglutination inhibition and enzyme-linked immunosorbent assay antibodies to RVF virus were also present in the same 24 serum samples. Indirect immunofluorescence was less sensitive in comparison with PRNT, and complement fixation was the least sensitive. These results extend observations made with laboratory animals to a large field-collected group of Egyptian sheep. PMID:3533977
ACTIVE IMMUNIZATION AGAINST POLIOMYELITIS IN MONKEYS.
Brodie, M; Goldbloom, A
1931-05-31
1. A combination of poliomyelitis virus and specific human serum is effective for the production of active immunity. 2. For each gram of active virus given intradermally as an emulsion, 6 cc. of human immune serum, injected subcutaneously, was required in our experiments to protect a monkey from paralysis. Some degree of active immunity was induced. 3. Immunity, without symptom of the disease, was secured when the serum was given at the time of inoculation, or within 3 days preceding or following inoculation of the virus. 4. For the production of immunity, virus, preceded by serum administration, is probably less effective than when it is given simultaneously with, or before, the injection of serum. 5. The virus neutralization test is more sensitive than the direct intracerebral test for determining the production of immunity.
Antibodies against MERS coronavirus in dromedary camels, United Arab Emirates, 2003 and 2013.
Meyer, Benjamin; Müller, Marcel A; Corman, Victor M; Reusken, Chantal B E M; Ritz, Daniel; Godeke, Gert-Jan; Lattwein, Erik; Kallies, Stephan; Siemens, Artem; van Beek, Janko; Drexler, Jan F; Muth, Doreen; Bosch, Berend-Jan; Wernery, Ulrich; Koopmans, Marion P G; Wernery, Renate; Drosten, Christian
2014-04-01
Middle East respiratory syndrome coronavirus (MERS-CoV) has caused an ongoing outbreak of severe acute respiratory tract infection in humans in the Arabian Peninsula since 2012. Dromedary camels have been implicated as possible viral reservoirs. We used serologic assays to analyze 651 dromedary camel serum samples from the United Arab Emirates; 151 of 651 samples were obtained in 2003, well before onset of the current epidemic, and 500 serum samples were obtained in 2013. Recombinant spike protein-specific immunofluorescence and virus neutralization tests enabled clear discrimination between MERS-CoV and bovine CoV infections. Most (632/651, 97.1%) camels had antibodies against MERS-CoV. This result included all 151 serum samples obtained in 2003. Most (389/651, 59.8%) serum samples had MERS-CoV-neutralizing antibody titers >1,280. Dromedary camels from the United Arab Emirates were infected at high rates with MERS-CoV or a closely related, probably conspecific, virus long before the first human MERS cases.
Harmon, Andrew W.; Moitra, Rituparna; Xu, Zhili
2018-01-01
Adenovirus vectors are widely used in gene therapy clinical trials, and preclinical studies with these vectors are often conducted in mice. It is therefore critical to understand whether mouse studies adequately predict the behavior of adenovirus vectors in humans. The most commonly-used adenovirus vectors are derived from adenovirus serotype 5 (Ad5). The Ad5 hexon protein can bind coagulation factor X (FX), and binding of FX has a major impact on vector interactions with other blood proteins. In mouse serum, FX protects Ad5 vectors from neutralization by natural antibodies and complement. In the current study, we similarly find that human FX inhibits neutralization of Ad5 vectors by human serum, and this finding is consistent among individual human sera. We show that human IgM and human IgG can each induce complement-mediated neutralization when Ad5 vectors are not protected by FX. Although mouse and human serum had similar effects on Ad5 vectors, we found that this was not true for a chimeric Ad5 vector that incorporated hexon regions from adenovirus serotype 48. Interestingly, this hexon-chimeric vector was neutralized by human serum, but not by mouse serum. These findings indicate that studies in mouse serum accurately predict the behavior of Ad5 vectors in human serum, but mouse serum is not an accurate model system for all adenovirus vectors. PMID:29401488
Evidence of neutralizing activity against T3 coliphage in oyster Crassostrea gigas hemolymph.
Bachère, E; Hervio, D; Mialhe, E; Grizel, H
1990-01-01
To investigate defense reactions of bivalve molluscs against viruses, experimental in vitro assays have been developed using T3 coliphage as a test virus. A native neutralizing factor in oyster Crassostrea gigas serum showed high individual variability and was enhanced significantly by repeated sampling of hemolymph from the same oysters. The responsible factor is apparently thermolabile and sensitive to EDTA treatment. Because of an inhibitory effect by the enzymatic inhibitor, phenylmethylsulphonyl fluoride (PMSF), the T3-neutralizing factor may be related to serine protease.
Immunological aspects of circulating DNA.
Anker, Philippe; Stroun, Maurice
2006-09-01
Nude mice were injected with DNA released by T lymphocytes previously exposed to inactivated herpes symplex type 1 or polio viruses. The serum of these mice was tested for its neutralizing activity. Injected nude mice synthesized antiherpetic or antipolio antibodies, depending on the antigen used to sensitize the T lymphocytes. Mice injected with DNA released by human T cells produced antibodies carrying human allotypes as they could be neutralized by antiallotype sera. However, mice that were injected with DNA released by antigen-stimulated murine T lymphocytes produced antiviral antibodies, which were not neutralized by anti-human allotype sera.
Nie, Jianhui; Wang, Wenbo; Wen, Zhiheng; Song, Aijing; Hong, Kunxue; Lu, Shan; Zhong, Ping; Xu, Jianqing; Kong, Wei; Li, Jingyun; Shang, Hong; Ling, Hong; Ruan, Li; Wang, Youchun
2012-11-01
Among the neutralizing antibody evaluation assays, the single-cycle pseudovirus infection assay is high-throughput and can provide rapid, sensitive and reproducible measurements after a single cycle of infection. Cell counts, pseudovirus inoculation levels, amount of diethylaminoethyl-dextran (DEAE-dextran), and the nonspecific effects of serum and plasma were tested to identify the optimal conditions for a neutralizing antibody assay based on pseudoviruses. Optimal conditions for cell counts, pseudovirus inoculation, and amount of DEAE-dextran were 1 × 10(4)cells/well, 200TCID(50)/well, and 15 μg/ml, respectively. Compared with serum samples, high-concentration anticoagulants reduced the relative light unit (RLU) value. The RLU value increased sharply initially but then decreased slowly with dilution of the plasma sample. Test kits containing 10 HIV-1 CRF07/08_BC pseudovirus strains and 10 plasma samples from individuals infected with HIV-1 CRF07/08_BC were assembled into two packages and distributed to nine laboratories with a standard operating procedure included. For the 10 laboratories that evaluated the test, 17 of 44 (37%) laboratory pairs were considered equivalent. A statistical qualification rule was developed based on the testing results from 5 experienced laboratories, where a laboratory qualified if at least 83% of values lied within the acceptable range. Copyright © 2012 Elsevier B.V. All rights reserved.
Miao, Li; Shi, Liwei; Yang, Yi; Yan, Kunming; Sun, Hongliang; Mo, Zhaojun; Li, Li
2018-04-01
This study evaluated the immunological effect of an aGV rabies virus strain using the Essen and Zagreb immunization programs. A total of 1,944 subjects were enrolled and divided into three groups: the Essen test group, Essen control group, and Zagreb test group. Neutralizing antibody levels and antibody seroconversion rates were determined at 7 and 14 days after the initial inoculations and then 14 days after the final inoculation in all of the subjects. The seroconversion rates for the Essen test group, Essen control group, and Zagreb test group, which were assessed 7 days after the first dosing in a susceptible population, were 35.74%, 26.92%, and 45.49%, respectively, and at 14 days, the seroconversion rates in this population were 100%, 100%, and 99.63%, respectively. At 14 days after the final dosing, the seroconversion rates were 100% in all three of the groups. The neutralizing serum antibody levels of the Essen test group, Essen control group, and Zagreb test group at 7 days after the first dosing in the susceptible population were 0.37, 0.26, and 0.56 IU/mL, respectively, and at 14 days after the initial dosing, these levels were 16.71, 13.85, and 16.80 IU/mL. At 14 days after the final dosing, the neutralizing antibody levels were 22.9, 16.3, and 18.62 IU/mL, respectively. The results of this study suggested that the aGV rabies vaccine using the Essen program resulted in a good serum immune response, and the seroconversion rates and the neutralizing antibody levels generated with the Zagreb regimen were higher than those with the Essen regimen when measured 7 days after the first dose.
Wieten, Rosanne W; Jonker, Emile F F; Pieren, Daan K J; Hodiamont, Caspar J; van Thiel, Pieter P A M; van Gorp, Eric C M; de Visser, Adriëtte W; Grobusch, Martin P; Visser, Leo G; Goorhuis, Abraham
2016-03-04
The 17D-yellow fever (YF) vaccination is considered contraindicated in immune-compromised patients; however, accidental vaccination occurs. In this population, measuring the immune response is useful in clinical practice. In this study we compare two antibody tests (the Immune Fluorescence Assay and the Plaque Reduction Neutralization Test) in a group of Dutch immune-compromised travellers with a median of 33 days (IQR [28-49]) after primary YF vaccination. We collected samples of 15 immune-compromised vaccinees vaccinated with the 17D yellow fever vaccine between 2004 and 2012. All samples measured in the plaque reduction neutralization test yielded positive results (>80% virus neutralization with a 1:10 serum dilution). Immune Fluorescence Assay sensitivity was 28% (95% CI [0.12-0.49]). No adverse events were reported. All immune-compromised patients mounted an adequate response with protective levels of virus neutralizing antibodies to the 17-D YF vaccine. No adverse effects were reported. Compared to the plaque reduction neutralization test, the sensitivity of the Immune Fluorescence Assay test was low. Further research is needed to ascertain that 17D vaccination in immune-compromised patients is safe. Copyright © 2016 Elsevier Ltd. All rights reserved.
Malerczyk, Claudius; Freuling, Conrad; Gniel, Dieter; Giesen, Alexandra; Selhorst, Thomas; Müller, Thomas
2014-01-01
Rabies is a neglected zoonotic disease caused by viruses belonging to the genus lyssavirus. In endemic countries of Asia and Africa, where the majority of the estimated 60,000 human rabies deaths occur, it is mainly caused by the classical rabies virus (RABV) transmitted by dogs. Over the last decade new species within the genus lyssavirus have been identified. Meanwhile 15 (proposed or classified) species exist, including Australian bat lyssavirus (ABLV), European bat lyssavirus (EBLV-1 and -2), Duvenhage virus (DUVV), as well as Lagos bat virus (LBV) and Mokola virus (MOKV) and recently identified novel species like Bokeloh bat lyssavirus (BBLV), Ikoma bat lyssavirus (IKOV) or Lleida bat lyssavirus (LLBV). The majority of these lyssavirus species are found in bat reservoirs and some have caused human infection and deaths. Previous work has demonstrated that Purified Chick Embryo Cell Rabies Vaccine (PCECV) not only induces immune responses against classical RABV, but also elicits cross-neutralizing antibodies against ABLV, EBLV-1 and EBLV-2. Using the same serum samples as in our previous study, this study extension investigated cross-neutralizing activities of serum antibodies measured by rapid fluorescent focus inhibition test (RFFIT) against selected other non-classical lyssavirus species of interest, namely DUVV and BBLV, as well as MOKV and LBV. Antibodies developed after vaccination with PCECV have neutralizing capability against BBLV and DUVV in the same range as against ABLV and EBLV-1 and -2. As expected, for the phylogenetically more distant species LBV no cross-neutralizing activity was found. Interestingly, 15 of 94 serum samples (16%) with a positive neutralizing antibody titer against RABV displayed specific cross-neutralizing activity (65-fold lower than against RABV) against one specific MOKV strain (Ethiopia isolate), which was not seen against a different strain (Nigeria isolate). Cross-neutralizing activities partly correlate with the phylogenetic distance of the virus species. Cross-neutralizing activities against the species BBLV and DUVV of phylogroup 1 were demonstrated, in line with previous results of cross-neutralizing activities against ABLV and EBLV-1 and -2. Potential partial cross-neutralizing activities against more distant lyssavirus species like selected MOKV strains need further research.
Zhou, Jie; Liao, Yu-xue; Chen, Zhong; Li, Yu-chun; Gao, Lu-Lu; Chen, Yi-xiong; Cai, Lian-gong; Chen, Qing; Yu, Shou-yi
2008-05-01
To develop an simple and sensitive method for detecting anti-coronavirus IgG antibodies in bat sera based on enzyme-linked immunosorbent assay (ELISA). A commercial ELISA kit for detecting SARS-CoV antibody was modified for detecting coronavirus antibodies in bat serum samples. The second antibody in the kit was replaced with horseradish peroxidase-conjugated protein-A (HRP-SPA) based on the characteristics of binding between Staphylococcus aureus protein A (SPA) and mammal IgG Fc fragment. The sera of 55 fulvous fruit bats (Rousettus dasymallus) were tested using the SPA-ELISA. The test results of the positive and negative controls in the kit and the serum samples from convalescent ;patient were consistent with expectation. Coronavirus antibody was detected in 2 out of the 55 bat serum samples. Serum neutralization test confirmed the validity of the SPA-ELISA method. This SPA-ELISA method is applicable for detecting coronavirus antibody in bat sera.
Walpurgis, Katja; Thomas, Andreas; Schänzer, Wilhelm; Thevis, Mario
2016-02-01
Myostatin is a key regulator of skeletal muscle growth and inhibition of its signaling pathway results in an increased muscle mass and function. The aim of this study was to develop a qualitative detection assay for myostatin-neutralizing antibodies for doping control purposes by using immunological approaches. To detect different types of myostatin-neutralizing antibodies irrespective of their amino acid sequence, an immunological assay specific for antibodies directed against myostatin and having a human Fc domain was established. Affinity purification and Western blotting strategies were combined to allow extracting and identifying relevant analytes from 200 μL of plasma/serum in a non-targeted approach. The assay was characterized regarding specificity, linearity, precision, robustness, and recovery. The assay was found to be highly specific, robust, and linear from 0.1 to 1 μg/mL. The precision was successfully specified at three different concentrations and the recovery of the affinity purification was 58%. Within this study, an immunological detection assay for myostatin-neutralizing antibodies present in plasma/serum specimens was developed and successfully characterized. The presented approach can easily be modified to include other therapeutic antibodies and serves as proof-of-concept for the detection of antibody-based myostatin inhibitors in doping control samples. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Bukbuk, David Nadeba; Fukushi, Shuetsu; Tani, Hideki; Yoshikawa, Tomoki; Taniguchi, Satoshi; Iha, Koichiro; Fukuma, Aiko; Shimojima, Masayuki; Morikawa, Shigeru; Saijo, Masayuki; Kasolo, Francis; Baba, Saka Saheed
2014-12-01
Rift Valley fever (RVF) is endemic to the tropical regions of eastern and southern Africa. The seroprevalence of RVF was investigated among the human population in Borno State, Nigeria to determine the occurrence of the disease in the study area in comparison with that of Lassa fever and Crimean-Congo Hemorrhagic fever. Recombinant nucleoprotein (rNP)-based IgG-ELISAs for the detection of serum antibodies against RVF virus (RVFV), Lassa fever virus (LASV), and Crimean-Congo hemorrhagic fever virus (CCHFV) were used to test human sera in Borno State, Nigeria. The presence of neutralizing antibody against the RVFV-glycoprotein-bearing vesicular stomatitis virus pseudotype (RVFVpv) was also determined in the human sera. Of the 297 serum samples tested, 42 (14.1%) were positive for the presence of RVFV-IgG and 22 (7.4%) and 7 (2.4%) of the serum samples were positive for antibodies against LASV and CCHFV, respectively. There was a positive correlation between the titers of neutralizing antibodies obtained using RVFVpv and those obtained using the conventional neutralization assay with the attenuated RVFV-MP12 strain. The seroprevalence of RVF was significantly higher than that of LASV and CCHF in Borno State, Nigeria. The RVFVpv-based neutralization assay developed in this study has the potential to replace the traditional assays based on live viruses for the diagnosis and seroepidemiological studies of RVF. © The Author 2014. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Tarr, Alexander W.; Urbanowicz, Richard A.; Hamed, Mohamed R.; Albecka, Anna; McClure, C. Patrick; Brown, Richard J. P.; Irving, William L.; Dubuisson, Jean; Ball, Jonathan K.
2011-01-01
Neutralizing antibodies have a role in controlling hepatitis C virus (HCV) infection. A successful vaccine will need to elicit potently neutralizing antibodies that are capable of preventing the infection of genetically diverse viral isolates. However, the specificity of the neutralizing antibody response in natural HCV infection still is poorly understood. To address this, we examined the reactivity of polyclonal antibodies isolated from chronic HCV infection to the diverse patient-isolated HCV envelope glycoproteins E1 and E2 (E1E2), and we also examined the potential to neutralize the entry of pseudoparticles bearing these diverse E1E2 proteins. The genetic type of the infection was found to determine the pattern of the antibody recognition of these E1E2 proteins, with the greatest reactivity to homologous E1E2 proteins. This relationship was strongest when the component of the antibody response directed only to linear epitopes was analyzed. In contrast, the neutralization serotype did not correlate with genotype. Instead, serum-derived antibodies displayed a range of neutralization breadth and potency, while different E1E2 glycoproteins displayed different sensitivities to neutralization, such that these could be divided broadly into neutralization-sensitive and -resistant phenotypes. An important additional observation was that entry mediated by some E1E2 proteins was enhanced in the presence of some of the polyclonal antibody fractions isolated during chronic infection. These data highlight the need to use diverse E1E2 isolates, which represent extremes of neutralization sensitivity, when screening antibodies for therapeutic potential and for testing antibodies generated following immunization as part of vaccine development. PMID:21325403
Li, Yong; Sekula, Peggy; Wuttke, Matthias; Wahrheit, Judith; Hausknecht, Birgit; Schultheiss, Ulla T; Gronwald, Wolfram; Schlosser, Pascal; Tucci, Sara; Ekici, Arif B; Spiekerkoetter, Ute; Kronenberg, Florian; Eckardt, Kai-Uwe; Oefner, Peter J; Köttgen, Anna
2018-05-01
Background The kidneys have a central role in the generation, turnover, transport, and excretion of metabolites, and these functions can be altered in CKD. Genetic studies of metabolite concentrations can identify proteins performing these functions. Methods We conducted genome-wide association studies and aggregate rare variant tests of the concentrations of 139 serum metabolites and 41 urine metabolites, as well as their pairwise ratios and fractional excretions in up to 1168 patients with CKD. Results After correction for multiple testing, genome-wide significant associations were detected for 25 serum metabolites, two urine metabolites, and 259 serum and 14 urinary metabolite ratios. These included associations already known from population-based studies. Additional findings included an association for the uremic toxin putrescine and variants upstream of an enzyme catalyzing the oxidative deamination of polyamines ( AOC1 , P -min=2.4×10 -12 ), a relatively high carrier frequency (2%) for rare deleterious missense variants in ACADM that are collectively associated with serum ratios of medium-chain acylcarnitines ( P -burden=6.6×10 -16 ), and associations of a common variant in SLC7A9 with several ratios of lysine to neutral amino acids in urine, including the lysine/glutamine ratio ( P =2.2×10 -23 ). The associations of this SLC7A9 variant with ratios of lysine to specific neutral amino acids were much stronger than the association with lysine concentration alone. This finding is consistent with SLC7A9 functioning as an exchanger of urinary cationic amino acids against specific intracellular neutral amino acids at the apical membrane of proximal tubular cells. Conclusions Metabolomic indices of specific kidney functions in genetic studies may provide insight into human renal physiology. Copyright © 2018 by the American Society of Nephrology.
Malerczyk, Claudius; Freuling, Conrad; Gniel, Dieter; Giesen, Alexandra; Selhorst, Thomas; Müller, Thomas
2014-01-01
Background: Rabies is a neglected zoonotic disease caused by viruses belonging to the genus lyssavirus. In endemic countries of Asia and Africa, where the majority of the estimated 60,000 human rabies deaths occur, it is mainly caused by the classical rabies virus (RABV) transmitted by dogs. Over the last decade new species within the genus lyssavirus have been identified. Meanwhile 15 (proposed or classified) species exist, including Australian bat lyssavirus (ABLV), European bat lyssavirus (EBLV-1 and -2), Duvenhage virus (DUVV), as well as Lagos bat virus (LBV) and Mokola virus (MOKV) and recently identified novel species like Bokeloh bat lyssavirus (BBLV), Ikoma bat lyssavirus (IKOV) or Lleida bat lyssavirus (LLBV). The majority of these lyssavirus species are found in bat reservoirs and some have caused human infection and deaths. Previous work has demonstrated that Purified Chick Embryo Cell Rabies Vaccine (PCECV) not only induces immune responses against classical RABV, but also elicits cross-neutralizing antibodies against ABLV, EBLV-1 and EBLV-2. Material & Methods: Using the same serum samples as in our previous study, this study extension investigated cross-neutralizing activities of serum antibodies measured by rapid fluorescent focus inhibition test (RFFIT) against selected other non-classical lyssavirus species of interest, namely DUVV and BBLV, as well as MOKV and LBV. Results: Antibodies developed after vaccination with PCECV have neutralizing capability against BBLV and DUVV in the same range as against ABLV and EBLV-1 and -2. As expected, for the phylogenetically more distant species LBV no cross-neutralizing activity was found. Interestingly, 15 of 94 serum samples (16%) with a positive neutralizing antibody titer against RABV displayed specific cross-neutralizing activity (65-fold lower than against RABV) against one specific MOKV strain (Ethiopia isolate), which was not seen against a different strain (Nigeria isolate). Conclusion: Cross-neutralizing activities partly correlate with the phylogenetic distance of the virus species. Cross-neutralizing activities against the species BBLV and DUVV of phylogroup 1 were demonstrated, in line with previous results of cross-neutralizing activities against ABLV and EBLV-1 and -2. Potential partial cross-neutralizing activities against more distant lyssavirus species like selected MOKV strains need further research. PMID:25483634
Humoral immunity to AAV-6, 8, and 9 in normal and dystrophic dogs.
Shin, Jin-Hong; Yue, Yongping; Smith, Bruce; Duan, Dongsheng
2012-03-01
Adeno-associated virus (AAV)-6, 8, and 9 are promising gene-delivery vectors for testing novel Duchenne muscular dystrophy gene therapy in the canine model. Humoral immunity greatly influences in vivo AAV transduction. However, neutralizing antibodies to AAV-6, 8, and 9 have not been systemically examined in normal and dystrophic dogs. To gain information on the seroprevalence of antibodies to AAV-6, 8, and 9, we measured neutralizing antibody titers using an in vitro transduction inhibition assay. We examined 72 naive serum samples and 26 serum samples obtained from dogs that had received AAV gene transfer. Our data demonstrated that AAV-6 neutralizing antibody was the most prevalent antibody in dogs irrespective of age, gender, disease status (dystrophic or not), and prior parvovirus vaccination history. Surprisingly, high-level anti-AAV-6 antibody was detected at birth in newborn puppies. Further, a robust antibody response was induced in affected, but not normal newborn dogs following systemic AAV gene transfer. Taken together, our data have provided an important baseline on the seroprevalence of AAV-6, 8, and 9 neutralizing antibodies in normal and Duchenne muscular dystrophy dogs. These results will help guide translational AAV gene-therapy studies in dog models of muscular dystrophy.
Evidence of Schmallenberg virus circulation in ruminants in Greece.
Chaintoutis, Serafeim C; Kiossis, Evangelos; Giadinis, Nektarios D; Brozos, Christos N; Sailleau, Corinne; Viarouge, Cyril; Bréard, Emmanuel; Papanastassopoulou, Maria; Zientara, Stéphan; Papadopoulos, Orestis; Dovas, Chrysostomos I
2014-01-01
During March 2013, we investigated the presence and the levels of Schmallenberg virus (SBV) circulation in three dairy cow herds and three sheep flocks in Central Macedonia, Greece. In two cow herds, a high number of abortions had been observed during the winter. Six bulk-tank milk samples and 147 individual sera were screened for SBV-specific antibodies by ELISA. Positive reactions were obtained from 5 out of 6 bulk-tank milk samples, 58 out of 90 sera from the 3 cow herds, and 2 sera from 2 of the 3 sheep flocks. Twenty-two ELISA-positive sera were tested by serum neutralization test (SNT). SNT confirmed the presence of neutralizing antibodies against SBV in all samples tested, with titers ranging between 1:32 and ≥1:256. No neutralizing antibodies against Akabane virus (AKAV) or Shamonda virus (SHAV) were detected, indicating that neutralizing antibodies against SBV do not cross react with AKAV or SHAV in SNT. ELISA testing of bulk-tank milk samples proved to be convenient and reliable. None of the tested sera was found positive for SBV by real-time RT-PCR, indicating that the sampling was conducted past the viremia stage. This is the first report of SBV circulation in Greece.
Horizontal transmission of the Leningrad-3 live attenuated mumps vaccine virus.
Atrasheuskaya, A V; Neverov, A A; Rubin, S; Ignatyev, G M
2006-03-06
Here we describe symptomatic transmission of the Leningrad-3 mumps vaccine virus from healthy vaccinees to previously vaccinated contacts. Throat swab and serum samples were taken from six symptomatic mumps cases and from 13 family contacts. Assessment of serum IgG and IgM anti-mumps virus antibodies and IgG avidity testing was performed using commercial test kits. Sera neutralizing antibodies were measured by plaque reduction neutralization assay using the L-3 vaccine mumps virus as the target. All six of the symptomatic mumps cases and three contact subjects tested positive for mumps by RT-PCR. The genomic sequences tested (F, SH and HN genes) of all nine of these samples were identical to the L-3 mumps vaccine strain. All 13 contacts were asymptomatic; however clear serological evidence of mumps infection was found in some of them. The likely epidemiological source of the transmitted L-3 mumps virus was children who were recently vaccinated at the schools attended by the six symptomatic mumps patients described here. The L-3 mumps vaccine virus can be shed and transmitted horizontally, even to subjects previously vaccinated with the same virus.
Hart, Lucas; Mackenzie, Ashley; Purcell, Maureen; Thompson, Rachel L.; Hershberger, Paul
2017-01-01
Methods for a plaque neutralization test (PNT) were optimized for the detection and quantification of viral hemorrhagic septicemia virus (VHSV) neutralizing activity in the plasma of Pacific Herring Clupea pallasii. The PNT was complement dependent, as neutralizing activity was attenuated by heat inactivation; further, neutralizing activity was mostly restored by the addition of exogenous complement from specific-pathogen-free Pacific Herring. Optimal methods included the overnight incubation of VHSV aliquots in serial dilutions (starting at 1:16) of whole test plasma containing endogenous complement. The resulting viral titers were then enumerated using a viral plaque assay in 96-well microplates. Serum neutralizing activity was virus-specific as plasma from viral hemorrhagic septicemia (VHS) survivors demonstrated only negligible reactivity to infectious hematopoietic necrosis virus, a closely related rhabdovirus. Among Pacific Herring that survived VHSV exposure, neutralizing activity was detected in the plasma as early as 37 d postexposure and peaked at approximately 64 d postexposure. The onset of neutralizing activity was slightly delayed in fish reared at 7.4°C relative to those in warmer temperatures (9.9°C and 13.1°C); however, neutralizing activity persisted for at least 345 d postexposure in all temperature treatments. It is anticipated that this novel ability to assess VHSV neutralizing activity in Pacific Herring will enable retrospective comparisons between prior VHS infections and year-class recruitment failures. Additionally, the optimized PNT could be employed as a forecasting tool capable of identifying the potential for future VHS epizootics in wild Pacific Herring populations.
Leopold, Philip L; Wendland, Rebecca L; Vincent, Theresa; Crystal, Ronald G
2006-10-01
Neutralization of adenovirus (Ad) by anti-Ad neutralizing antibodies in serum involves formation of Ad-immune complexes that prevent the virus from interacting with target cells. We hypothesized that Ad-immune complexes likely contain viable Ad vectors which, although no longer capable of gaining access to receptors on target cells, may be able to express transgenes in cells bearing Fc receptors for immunoglobulins, i.e., that antibody-based "neutralization" of Ad vectors may be circumvented by the Fc receptor pathway. To test this hypothesis, we expressed the Fcgamma receptor IIA (FcgammaR) in A549 lung epithelial cells or human dermal fibroblasts and evaluated gene transfer in the presence of human neutralizing anti-Ad serum. FcgammaR-expressing cells bound and internalized copious amounts of Ad, with a distinct population of internalized Ad trafficking to the nucleus. The dose-response curves for inhibition of gene transfer revealed that FcgammaR-expressing cells required a more-than-10-fold higher concentration of anti-Ad serum to achieve 50% inhibition of Ad-encoded beta-galactosidase expression compared with non-FcgammaR-expressing cells. The discrepancy between neutralization of Ad during infection of FcgammaR-expressing cells and neutralization of Ad during infection of non-FcgammaR-expressing cells occurred with either heat-inactivated or non-heat-inactivated sera, was blocked by addition of purified Fc domain protein, and did not require the cytoplasmic domain of FcgammaR, suggesting that immune complex internalization proceeded via endocytosis rather than phagocytosis. FcgammaR-mediated infection by Ad-immune complexes did not require expression of the coxsackie virus-Ad receptor (CAR) since similar data were obtained when CAR-deficient human dermal fibroblasts were engineered to express FcgammaR. However, interaction of the Ad penton base with cell surface integrins contributed to the difference in neutralization between FcgammaR-expressing and non-FcgammaR-expressing cells. The data indicate that complexes formed from Ad and anti-Ad neutralizing antibodies, while compromised with respect to infection of non-FcgammaR-expressing target cells, maintain the potential to transfer genes to FcgammaR-expressing cells, with consequent expression of the transgene. The formation of Ad-immune complexes that can target viable virus to antigen-presenting cells may account for the success of Ad-based vaccines administered in the presence of low levels of neutralizing anti-Ad antibody.
Fukushi, Shuetsu; Fukuma, Aiko; Kurosu, Takeshi; Watanabe, Shumpei; Shimojima, Masayuki; Shirato, Kazuya; Iwata-Yoshikawa, Naoko; Nagata, Noriyo; Ohnishi, Kazuo; Ato, Manabu; Melaku, Simenew Keskes; Sentsui, Hiroshi; Saijo, Masayuki
2018-01-01
Since discovering the Middle East respiratory syndrome coronavirus (MERS-CoV) as a causative agent of severe respiratory illness in the Middle East in 2012, serological testing has been conducted to assess antibody responses in patients and to investigate the zoonotic reservoir of the virus. Although the virus neutralization test is the gold standard assay for MERS diagnosis and for investigating the zoonotic reservoir, it uses live virus and so must be performed in high containment laboratories. Competitive ELISA (cELISA), in which a labeled monoclonal antibody (MAb) competes with test serum antibodies for target epitopes, may be a suitable alternative because it detects antibodies in a species-independent manner. In this study, novel MAbs against the spike protein of MERS-CoV were produced and characterized. One of these MAbs was used to develop a cELISA. The cELISA detected MERS-CoV-specific antibodies in sera from MERS-CoV-infected rats and rabbits immunized with the spike protein of MERS-CoV. The MAb-based cELISA was validated using sera from Ethiopian dromedary camels. Relative to the neutralization test, the cELISA detected MERS-CoV-specific antibodies in 66 Ethiopian dromedary camels with a sensitivity and specificity of 98% and 100%, respectively. The cELISA and neutralization test results correlated well (Pearson's correlation coefficients=0.71-0.76, depending on the cELISA serum dilution). This cELISA may be useful for MERS epidemiological investigations on MERS-CoV infection. Copyright © 2017 Elsevier B.V. All rights reserved.
Archer, B. G.; Dierks, R. E.
1968-01-01
Heterologous antirabies serum is commonly used in the treatment of persons exposed to rabies. However, the high incidence of serum sickness which accompanies its use has prompted work to develop a homologous human product. As human antirabies serum is expensive and difficult to obtain in large quantities, a series of experiments was done on guinea-pigs to test the effects of homologous and heterologous antirabies serum. Similar amounts of homologous and heterologous antisera administered to guinea-pigs produced similar circulating neutralization titres one day later. The homologous antibody titres, however, decreased more slowly than the heterologous antibody titres. When homologous antiserum was given, followed by duck-embryo rabies vaccine, an apparent response to the vaccine was suppressed or delayed longer than when heterologous antiserum and vaccine were administered. However, when homologous antiserum was given with suckling-mouse-brain vaccine, of a much higher potency, the response to vaccine was apparent in the presence of a passive titre of 1:120. If a similar relationship is seen in man with the use of a homologous antirabies product, it will be essential to use high potency vaccines or alter the established vaccination schedules in order to overcome the inherent interference problems. PMID:5303907
Zauberman, Ayelet; Cohen, Sara; Levy, Yinon; Halperin, Gideon; Lazar, Shirley; Velan, Baruch; Shafferman, Avigdor; Flashner, Yehuda; Mamroud, Emanuelle
2008-03-20
Plague is a life-threatening disease caused by Yersinia pestis, for which effective-licensed vaccines and reliable predictors of in vivo immunity are lacking. V antigen (LcrV) is a major Y. pestis virulence factor that mediates translocation of the cytotoxic Yersinia protein effectors (Yops). It is a well-established protective antigen and a part of currently tested plague subunit vaccines. We have developed a highly sensitive in vitro macrophage cytotoxicity neutralization assay which is mediated by anti-LcrV antibodies; and studied the potential use of these neutralizing antibodies as an in vitro correlate of plague immunity in mice. The assay is based on a Y. pestis strain with enhanced cytotoxicity to macrophages in which endogenous yopJ was replaced by the more effectively translocated yopP of Y. enterocolitica O:8. Mice passively immunized with rabbit anti-LcrV IgG or actively immunized with recombinant LcrV were protected against lethal doses of a virulent Y. pestis strain, in a mouse model of bubonic plague. This protection significantly correlated with the in vitro neutralizing activity of the antisera but not with their corresponding ELISA titers. In actively immunized mice, a cutoff value for serum neutralizing activity, above which survival was assured with high degree of confidence, could be established for different vaccination regimes. The impact of overall findings on the potential use of serum neutralizing activity as a correlate of protective immunity is discussed.
Crawford, Sue E.; Estes, Mary K.; Ciarlet, Max; Barone, Christopher; O’Neal, Christine M.; Cohen, Jean; Conner, Margaret E.
1999-01-01
The recognition that rotaviruses are the major cause of life-threatening diarrheal disease and significant morbidity in young children has focused efforts on disease prevention and control of these viruses. Although the correlates of protection in children remain unclear, some studies indicate that serotype-specific antibody is important. Based on this premise, current live attenuated reassortant rotavirus vaccines include the four predominant serotypes of virus. We are evaluating subunit rotavirus vaccines, 2/6/7-VLPs and 2/4/6/7-VLPs, that contain only a single VP7 of serotype G1 or G3. In mice immunized parenterally twice, G3 virus-like particles (VLPs) induced a homotypic, whereas G1 VLPs induced a homotypic and heterotypic (G3) serum neutralizing immune response. Administration of three doses of G1 or G3 VLPs induced serum antibodies that neutralized five of seven different serotype test viruses. The inclusion of VP4 in the VLPs was not essential for the induction of heterotypic neutralizing antibody in mice. To confirm these results in another species, rabbits were immunized parenterally with two doses of 2/4/6/7-VLPs containing a G3 or G1 VP7, sequentially with G3 VLPs followed by G1 (G3/G1) VLPs, or with live or psoralen-inactivated SA11. High-titer homotypic serum neutralizing antibody was induced in all rabbits, and low-level heterotypic neutralizing antibody was induced in a subset of rabbits. The rabbits immunized with the G1 or G3/G1 VLPs in QS-21 were challenged orally with live G3 ALA rotavirus. Protection levels were similar in rabbits immunized with homotypic G3 2/4/6/7-VLPs, heterotypic G1 2/4/6/7-VLPs, or G3/G1 2/4/6/7-VLPs. Therefore, G1 2/4/6/7-VLPs can induce protective immunity against a live heterotypic rotavirus challenge in an adjuvant with potential use in humans. Following challenge, broad serum heterotypic neutralizing antibody responses were detected in rabbits parenterally immunized with G1, G3/G1, or G3 VLPs but not with SA11. Immunization with VLPs may provide sufficient priming of the immune system to induce protective anamnestic heterotypic neutralizing antibody responses upon subsequent rotavirus infection. Therefore, a limited number of serotypes of VLPs may be sufficient to provide a broadly protective subunit vaccine. PMID:10233942
Wang, Joshua W.; Jagu, Subhashini; Wu, Wai-Hong; Viscidi, Raphael P.; Macgregor-Das, Anne; Fogel, Jessica M.; Kwak, Kihyuck; Daayana, Sai; Kitchener, Henry; Stern, Peter L.; Gravitt, Patti E.; Trimble, Cornelia L.
2015-01-01
Presently, the seroprevalence of human papillomavirus (HPV) minor capsid antigen L2-reactive antibody is not well understood, and no serologic standard exists for L2-specific neutralizing antibodies. Therefore, we screened a total of 1,078 serum samples for HPV16 L2 reactivity, and these were obtained from four prior clinical studies: a population-based (n = 880) surveillance study with a high-risk HPV DNA prevalence of 10.8%, a cohort study of women (n = 160) with high-grade cervical intraepithelial neoplasia (CIN), and two phase II trials in women with high-grade vulvar intraepithelial neoplasia (VIN) receiving imiquimod therapy combined with either photodynamic therapy (PDT) (n = 19) or vaccination with a fusion protein comprising HPV16 L2, E7, and E6 (TA-CIN) (n = 19). Sera were screened sequentially by HPV16 L2 enzyme-linked immunosorbent assay (ELISA) and then Western blot. Seven of the 1,078 serum samples tested had L2-specific antibodies, but none were detectably neutralizing for HPV16. To develop a standard, we substituted human IgG1 sequences into conserved regions of two rodent monoclonal antibodies (MAbs) specific for neutralizing epitopes at HPV16 L2 residues 17 to 36 and 58 to 64, creating JWW-1 and JWW-2, respectively. These chimeric MAbs retained neutralizing activity and together reacted with 33/34 clinically relevant HPV types tested. In conclusion, our inability to identify an HPV16 L2-specific neutralizing antibody response even in the sera of patients with active genital HPV disease suggests the subdominance of L2 protective epitopes and the value of the chimeric MAbs JWW-1 and JWW-2 as standards for immunoassays to measure L2-specific human antibodies. PMID:25972404
Campi-Azevedo, Ana Carolina; Peruhype-Magalhães, Vanessa; Coelho-Dos-Reis, Jordana Grazziela; Costa-Pereira, Christiane; Yamamura, Anna Yoshida; Lima, Sheila Maria Barbosa de; Simões, Marisol; Campos, Fernanda Magalhães Freire; de Castro Zacche Tonini, Aline; Lemos, Elenice Moreira; Brum, Ricardo Cristiano; de Noronha, Tatiana Guimarães; Freire, Marcos Silva; Maia, Maria de Lourdes Sousa; Camacho, Luiz Antônio Bastos; Rios, Maria; Chancey, Caren; Romano, Alessandro; Domingues, Carla Magda; Teixeira-Carvalho, Andréa; Martins-Filho, Olindo Assis
2017-09-01
Technological innovations in vaccinology have recently contributed to bring about novel insights for the vaccine-induced immune response. While the current protocols that use peripheral blood samples may provide abundant data, a range of distinct components of whole blood samples are required and the different anticoagulant systems employed may impair some properties of the biological sample and interfere with functional assays. Although the interference of heparin in functional assays for viral neutralizing antibodies such as the functional plaque-reduction neutralization test (PRNT), considered the gold-standard method to assess and monitor the protective immunity induced by the Yellow fever virus (YFV) vaccine, has been well characterized, the development of pre-analytical treatments is still required for the establishment of optimized protocols. The present study intended to optimize and evaluate the performance of pre-analytical treatment of heparin-collected blood samples with ecteola-cellulose (ECT) to provide accurate measurement of anti-YFV neutralizing antibodies, by PRNT. The study was designed in three steps, including: I. Problem statement; II. Pre-analytical steps; III. Analytical steps. Data confirmed the interference of heparin on PRNT reactivity in a dose-responsive fashion. Distinct sets of conditions for ECT pre-treatment were tested to optimize the heparin removal. The optimized protocol was pre-validated to determine the effectiveness of heparin plasma:ECT treatment to restore the PRNT titers as compared to serum samples. The validation and comparative performance was carried out by using a large range of serum vs heparin plasma:ECT 1:2 paired samples obtained from unvaccinated and 17DD-YFV primary vaccinated subjects. Altogether, the findings support the use of heparin plasma:ECT samples for accurate measurement of anti-YFV neutralizing antibodies. Copyright © 2017 Elsevier B.V. All rights reserved.
Drexler, Jan Felix; Grard, Gilda; Lukashev, Alexander N.; Kozlovskaya, Liubov I.; Böttcher, Sindy; Uslu, Gökhan; Reimerink, Johan; Gmyl, Anatoly P.; Taty-Taty, Raphaël; Lekana-Douki, Sonia Etenna; Nkoghe, Dieudonné; Eis-Hübinger, Anna M.; Diedrich, Sabine; Koopmans, Marion; Leroy, Eric M.; Drosten, Christian
2014-01-01
In 2010, a large outbreak of poliomyelitis with unusual 47% lethality occurred in Pointe Noire, Republic of Congo. Vaccine-mediated immunity against the outbreak virus was never investigated. A wild poliovirus 1 (WPV1) isolated from a fatal case (termed PV1-RC2010) showed a previously unknown combination of amino acid exchanges in critical antigenic site 2 (AgS2, VP1 capsid protein positions 221SAAL→221PADL). These exchanges were also detected in an additional 11 WPV1 strains from fatal cases. PV1-RC2010 escaped neutralization by three different mAbs relevant for AgS2. Virus neutralization was tested in sera from fatal cases, who died before supplementary immunization (n = 24), Gabonese recipients of recent oral polio vaccination (n = 12), routinely vaccinated German medical students (n = 34), and German outpatients tested for antipoliovirus immunity (n = 17) on Vero, human rhabdomyosarcoma, and human epidermoid carcinoma 2 cells. Fatal poliomyelitis cases gave laboratory evidence of previous trivalent vaccination. Neutralizing antibody titers against PV1-RC2010 were significantly lower than those against the vaccine strain Sabin-1, two genetically distinct WPV1s isolated in 1965 and 2010 and two genetically distinct vaccine-derived PV strains. Of German vaccinees tested according to World Health Organization protocols, 15–29% were unprotected according to their neutralization titers (<1:8 serum dilution), even though all were protected against Sabin-1. Phylogenetic analysis of the WPV1 outbreak strains suggested a recent introduction of virus progenitors from Asia with formation of separate Angolan and Congolese lineages. Only the latter carried both critical AgS2 mutations. Antigenetically variant PVs may become relevant during the final phase of poliomyelitis eradication in populations with predominantly vaccine-derived immunity. Sustained vaccination coverage and clinical and environmental surveillance will be necessary. PMID:25136105
Drexler, Jan Felix; Grard, Gilda; Lukashev, Alexander N; Kozlovskaya, Liubov I; Böttcher, Sindy; Uslu, Gökhan; Reimerink, Johan; Gmyl, Anatoly P; Taty-Taty, Raphaël; Lekana-Douki, Sonia Etenna; Nkoghe, Dieudonné; Eis-Hübinger, Anna M; Diedrich, Sabine; Koopmans, Marion; Leroy, Eric M; Drosten, Christian
2014-09-02
In 2010, a large outbreak of poliomyelitis with unusual 47% lethality occurred in Pointe Noire, Republic of Congo. Vaccine-mediated immunity against the outbreak virus was never investigated. A wild poliovirus 1 (WPV1) isolated from a fatal case (termed PV1-RC2010) showed a previously unknown combination of amino acid exchanges in critical antigenic site 2 (AgS2, VP1 capsid protein positions 221SAAL → 221PADL). These exchanges were also detected in an additional 11 WPV1 strains from fatal cases. PV1-RC2010 escaped neutralization by three different mAbs relevant for AgS2. Virus neutralization was tested in sera from fatal cases, who died before supplementary immunization (n = 24), Gabonese recipients of recent oral polio vaccination (n = 12), routinely vaccinated German medical students (n = 34), and German outpatients tested for antipoliovirus immunity (n = 17) on Vero, human rhabdomyosarcoma, and human epidermoid carcinoma 2 cells. Fatal poliomyelitis cases gave laboratory evidence of previous trivalent vaccination. Neutralizing antibody titers against PV1-RC2010 were significantly lower than those against the vaccine strain Sabin-1, two genetically distinct WPV1s isolated in 1965 and 2010 and two genetically distinct vaccine-derived PV strains. Of German vaccinees tested according to World Health Organization protocols, 15-29% were unprotected according to their neutralization titers (<1:8 serum dilution), even though all were protected against Sabin-1. Phylogenetic analysis of the WPV1 outbreak strains suggested a recent introduction of virus progenitors from Asia with formation of separate Angolan and Congolese lineages. Only the latter carried both critical AgS2 mutations. Antigenetically variant PVs may become relevant during the final phase of poliomyelitis eradication in populations with predominantly vaccine-derived immunity. Sustained vaccination coverage and clinical and environmental surveillance will be necessary.
West Nile encephalitis outbreak in Kerala, India, 2011.
Anukumar, B; Sapkal, Gajanan N; Tandale, Babasheb V; Balasubramanian, R; Gangale, Daya
2014-09-01
An outbreak of acute encephalitis syndrome (AES) was reported in Kerala in India in May 2011. The outbreak features were unusual in terms of seasonality, geographical distribution, age group, and clinical manifestations in comparison to the epidemiological features of Japanese Encephalitis. To detect the etiology of the acute encephalitis syndrome outbreak. Investigation of outbreak was undertaken by collection of brief clinical history and epidemiological details along with the specimens for viral diagnosis. The serum/CSF samples (patients=208) received from the sentinel hospitals were subjected to IgM capture ELISA and RT-PCR specific for Japanese encephalitis (JE) virus and West Nile virus (WNV). The JE/WN IgM positive samples were further tested by serum neutralization assay for the presence of JE and WNV specific neutralizing antibody. Most of the affected patients were aged above 15 years. No spatial clustering of the disease was noticed. Cases were observed in premonsoon and early monsoon season and in JE non-endemic area of Kerala. A total of 47 patient samples were positive for in-house JE IgM capture ELISA and WNV IgM capture ELISA. Serum neutralization assay result revealed that 32 of 42 (76.19%) sera were positive for WNV neutralization antibodies. WNV was isolated from a clinical specimen. Phylogenetic analysis of WNV envelope gene revealed 99% homology with Russian Lineage 1 WNV. West Nile virus (WNV) etiology was confirmed by virus isolation and detection of virus specific antibody from clinical specimen. Phylogenetic analysis grouped the current strain in lineage I West Nile virus. Copyright © 2014 Elsevier B.V. All rights reserved.
Serological reactions in Rhesus monkeys inoculated with the 17D strain of yellow fever virus.
GROOT, H
1962-01-01
Haemagglutination-inhibition tests, which depend on the appearance of haemagglutination-inhibiting antibodies in the serum in virus infections, are in common use in the study of arthropod-borne diseases. This paper contains the results of an investigation into the appearance and pattern of haemagglutination-inhibiting antibodies in the serum of rhesus monkeys inoculated intracerebrally with the 17D strain of yellow fever virus during the testing of seed lots of yellow fever vaccine. These antibodies appeared on the tenth day after inoculation, and were still demonstrable four years later. In all of the eight monkeys tested complement-fixing and neutralizing antibodies against yellow fever antigens also developed, and in six out of the eight heterologous antigens developed.
Humoral Immunity to AAV-6, 8, and 9 in Normal and Dystrophic Dogs
Shin, Jin-Hong; Yue, Yongping; Smith, Bruce
2012-01-01
Abstract Adeno-associated virus (AAV)-6, 8, and 9 are promising gene-delivery vectors for testing novel Duchenne muscular dystrophy gene therapy in the canine model. Humoral immunity greatly influences in vivo AAV transduction. However, neutralizing antibodies to AAV-6, 8, and 9 have not been systemically examined in normal and dystrophic dogs. To gain information on the seroprevalence of antibodies to AAV-6, 8, and 9, we measured neutralizing antibody titers using an in vitro transduction inhibition assay. We examined 72 naive serum samples and 26 serum samples obtained from dogs that had received AAV gene transfer. Our data demonstrated that AAV-6 neutralizing antibody was the most prevalent antibody in dogs irrespective of age, gender, disease status (dystrophic or not), and prior parvovirus vaccination history. Surprisingly, high-level anti-AAV-6 antibody was detected at birth in newborn puppies. Further, a robust antibody response was induced in affected, but not normal newborn dogs following systemic AAV gene transfer. Taken together, our data have provided an important baseline on the seroprevalence of AAV-6, 8, and 9 neutralizing antibodies in normal and Duchenne muscular dystrophy dogs. These results will help guide translational AAV gene-therapy studies in dog models of muscular dystrophy. PMID:22040468
West Nile virus-neutralizing antibodies in wild birds from southern Spain.
Ferraguti, M; LA Puente, J Martínez-DE; Soriguer, R; Llorente, F; Jiménez-Clavero, M Á; Figuerola, J
2016-07-01
West Nile virus (WNV) is an emerging vector-borne arbovirus with a zoonotic life-cycle whose main reservoir hosts are birds. In humans and horses, WNV infections rarely result in clinical disease but on occasions - depending on factors such as climatic conditions, insect communities and background immunity levels in local populations - they can lead to outbreaks that threaten public and animal health. We tested for the presence of WNV antibodies in 149 birds belonging to 32 different species. Samples were first tested using a bird-specific ELISA kit and then both positive and doubtful results were confirmed by neutralization tests using WNV and Usutu virus. WNV antibodies were confirmed in a resident Sylvia melanocephala juvenile, supporting the idea of local transmission of WNV in southern Spain in 2013. In addition, the serum from an adult blackbird (Turdus merula) showed neutralization of both WNV and Usutu virus. We discuss our results in light of the occurrence of WNV on horse farms in southern Spain in 2013.
Serum IFN neutralizing antibodies and neopterin levels in a cross-section of MS patients.
Cook, S D; Quinless, J R; Jotkowitz, A; Beaton, P
2001-09-25
To determine levels of serum interferon beta (IFNbeta) neutralizing antibody (NAb) and neopterin-an IFN biologic response marker-in patients with MS treated with Betaseron or Avonex. Controversy exists over the relative immunogenicity of IFNbeta-1a and IFNbeta-1b and the reasons for any such difference. To determine the role of patient profile and test methodology in IFNbeta, NAb levels need to be measured blindly and simultaneously in a predefined closely matched MS patient cohort. Serum NAb and neopterin levels were measured in closely matched patients on Avonex (n = 98) or Betaseron (n = 64). NAb were determined by Athena Diagnostics and serum neopterin levels by Covance Laboratories using a competitive binding radioimmunoassay. More patients taking Betaseron (22%) than Avonex (7%) had elevated titers of NAb (p = 0.008). Mean serum neopterin levels were lower in patients with high as compared to low NAb titers (p = 0.0002). No difference in mean neopterin levels was found comparing the total Betaseron group to the Avonex group; however, in the subset of patients with low NAb titers, mean neopterin levels were higher in the Betaseron than in the Avonex group (p = 0.027). A random cross-sectional sampling of patients on Avonex showed a decrease in neopterin levels over time between weekly doses. NAb are more commonly found with Betaseron than Avonex. More studies are needed to determine the correlation among serum neopterin levels, other biologic response markers, NAb, and disease activity in patients with MS being treated with IFNbeta.
Fatal vaccine-induced canine distemper virus infection in black-footed ferrets
Carpenter, J.W.; Appel, M.J.G.; Erickson, R.C.; Novilla, M.N.
1976-01-01
Four black-footed ferrets that were live-trapped in South Dakota and transported to the Patuxent Wildlife Research Center died within 21 days after vaccination with modified live canine distemper virus. Immunofluorescence, European ferret inoculation, virus isolation attempts, and serum-neutralization tests indicated insufficient attenuation of the vaccine for this species.
Fatal vaccine-induced canine distemper virus infection in black-footed ferrets.
Carpenter, J W; Appel, M J; Erickson, R C; Novilla, M N
1976-11-01
Four black-footed ferrets that were live-trapped in South Dakota and transported to the Patuxent Wildlife Research Center died within 21 days after vaccination with modified live canine distemper virus. Immunofluorescence, European ferret inoculation, virus isolation attempts, and serum-neutralization tests indicated insufficient attenuation of the vaccine for this species.
NASA Astrophysics Data System (ADS)
Gorczynski, Reginald M.; Gorczynski, Christopher P.; Gorczynski, Laura Y.; Hu, Jiang; Lu, Jin; Manuel, Justin; Lee, Lydia
2005-05-01
We examined expression of genes associated with cytokine production, and genes implicated in regulating bone metabolism, in bone stromal and osteoblast cells incubated under standard ground conditions and under conditions of neutral buoyancy, and in the presence/absence of serum from normal or sleep-deprived mice. We observed a clear interaction between these two conditions (exposure to neutral buoyancy and serum stimulation) in promoting enhanced osteoclastogenesis. Both conditions independently altered expression of a number of cytokines implicated in the regulation of bone metabolism. However, using stromal cells from IL-1 and TNF α cytokine r KO mice, we concluded that the increased bone loss under microgravity conditions was not primarily cytokine mediated.
Ainai, Akira; Tamura, Shin-ichi; Suzuki, Tadaki; van Riet, Elly; Ito, Ryo; Odagiri, Takato; Tashiro, Masato; Kurata, Takeshi; Hasegawa, Hideki
2013-01-01
Haemagglutination inhibition (HI) and neutralization (NT) titers as well as haemagglutinin (HA) specific antibody responses were examined in 50 healthy adults aged between 22 and 69 y old after two intranasal administrations of an inactivated whole virus vaccine derived from A/Victoria/210/2009 virus (45 μg HA per dose) at 3 week intervals. Serum HI titers after two-doses of the nasal vaccine showed >2.5-fold rise in the ratio of geometric mean titer upon vaccination, >40% of subjects with a ≥4-fold increase in titer and >70% of subjects with a titer of ≥1:40, all parameters associated with an effective outcome of vaccination in the criteria defined by the European Medicines Agency. Serum neutralizing antibody responses correlated with HI antibody responses, although NT titers were about 2-fold higher than HI titers. These high levels of serum responses were accompanied by high levels of HI and neutralizing antibody responses in nasal mucus as measured in concentrated nasal wash samples that were about 10 times diluted compared with natural nasal mucus. Serum and nasal HI and neutralizing antibody responses consisted of HA-specific IgG and IgA antibody responses, with IgG and IgA antibodies being dominant in serum and nasal responses, respectively. PMID:23896606
Indigenous West Nile virus infections in horses in Albania.
Berxholi, K; Ziegler, U; Rexhepi, A; Schmidt, K; Mertens, M; Korro, K; Cuko, A; Angenvoort, J; Groschup, M H
2013-11-01
Serum samples collected from 167 equines of 12 districts in Albania were tested for West Nile virus-specific antibodies by enzyme-linked immunosorbent assay and virus neutralization assay, using WNV lineage 1 and 2. In addition, 95 bird serum samples from Albania and 29 horse samples from Kosovo were tested in ELISA. An overall seroprevalence rate of 22% was found in horses from Albania, whereas no specific antibodies were found in the equine samples from Kosovo and the bird samples. This is the first report indicating WNV infections in animals in Albania, and the first reported seroprevalence study conducted for Kosovo. These results provide evidence for widespread infections of WNV in Albania. © 2013 Blackwell Verlag GmbH.
Euler, Zelda; van den Kerkhof, Tom L. G. M.; van Gils, Marit J.; Burger, Judith A.; Edo-Matas, Diana; Phung, Pham; Wrin, Terri
2012-01-01
We previously established that at 3 years postseroconversion, ∼30% of HIV-infected individuals have cross-reactive neutralizing activity (CrNA) in their sera. Here we studied the kinetics with which CrNA develops and how these relate to the development of autologous neutralizing activity as well as viral escape and diversification. For this purpose, sera from five individuals with CrNA and one elite neutralizer that were obtained at three monthly intervals in the first year after seroconversion and at multiple intervals over the disease course were tested for neutralizing activity against an established multiclade panel of six viruses. The same serum samples, as well as sera from three individuals who lacked CrNA, were tested for their neutralizing activities against autologous clonal HIV-1 variants from multiple time points covering the disease course from seroconversion onward. The elite neutralizer already had CrNA at 9.8 months postseroconversion, in contrast with the findings for the other five patients, in whom CrNA was first detected at 20 to 35 months postseroconversion and peaked around 35 months postseroconversion. In all patients, CrNA coincided with neutralizing activity against autologous viruses that were isolated <12 months postseroconversion, while viruses from later time points had already escaped autologous neutralizing activity. Also, the peak in gp160 sequence diversity coincided with the peak of CrNA titers. Individuals who lacked CrNA had lower peak autologous neutralizing titers, viral escape, and sequence diversity than individuals with CrNA. A better understanding of the underlying factors that determine the presence of CrNA or even an elite neutralizer phenotype may aid in the design of an HIV-1 vaccine. PMID:22156522
Pedersen, Gabriel Kristian; Höschler, Katja; Øie Solbak, Sara Marie; Bredholt, Geir; Pathirana, Rishi Delan; Afsar, Aram; Breakwell, Lucy; Nøstbakken, Jane Kristin; Raae, Arnt Johan; Brokstad, Karl Albert; Sjursen, Haakon; Zambon, Maria; Cox, Rebecca Jane
2014-07-31
Influenza H5N1 virus constitutes a pandemic threat and development of effective H5N1 vaccines is a global priority. Anti-influenza antibodies directed towards the haemagglutinin (HA) define a correlate of protection. Both antibody concentration and avidity may be important for virus neutralization and resolving influenza disease. We conducted a phase I clinical trial of a virosomal H5N1 vaccine adjuvanted with the immunostimulating complex Matrix M™. Sixty adults were intramuscularly immunized with two vaccine doses (21 days apart) of 30 μg HA alone or 1.5, 7.5 or 30 μg HA adjuvanted with Matrix M™. Serum H5 HA1-specific antibodies and virus neutralization were determined at days 0, 21, 42, 180 and 360 and long-term memory B cells at day 360 post-vaccination. The binding of the HA specific antibodies was measured by avidity NaSCN-elution ELISA and surface plasmon resonance (SPR). The H5 HA1-specific IgG response peaked after the second dose (day 42), was dominated by IgG1 and IgG3 and was highest in the adjuvanted vaccine groups. IgG titres correlated significantly with virus neutralization at all time points (Spearman r≥0.66, p<0.0001). By elution ELISA, serum antibody avidity was highest at days 180 and 360 post vaccination and did not correlate with virus neutralization. Long-lasting H5 HA1-specific memory B cells produced high IgG antibody avidity similar to serum IgG. Maturation of serum antibody avidity continued up to day 360 after influenza H5N1 vaccination. Virus neutralization correlated with serum H5 HA1-specific IgG antibody concentrations and not antibody avidity. Copyright © 2014 Elsevier Ltd. All rights reserved.
Arenavirus Glycan Shield Promotes Neutralizing Antibody Evasion and Protracted Infection
Malinge, Pauline; Magistrelli, Giovanni; Fischer, Nicolas; Sahin, Mehmet; Bergthaler, Andreas; Igonet, Sebastien; ter Meulen, Jan; Rigo, Dorothée; Meda, Paolo; Rabah, Nadia; Coutard, Bruno; Bowden, Thomas A.; Lambert, Paul-Henri; Siegrist, Claire-Anne; Pinschewer, Daniel D.
2015-01-01
Arenaviruses such as Lassa virus (LASV) can cause severe hemorrhagic fever in humans. As a major impediment to vaccine development, delayed and weak neutralizing antibody (nAb) responses represent a unifying characteristic of both natural infection and all vaccine candidates tested to date. To investigate the mechanisms underlying arenavirus nAb evasion we engineered several arenavirus envelope-chimeric viruses and glycan-deficient variants thereof. We performed neutralization tests with sera from experimentally infected mice and from LASV-convalescent human patients. NAb response kinetics in mice correlated inversely with the N-linked glycan density in the arenavirus envelope protein’s globular head. Additionally and most intriguingly, infection with fully glycosylated viruses elicited antibodies, which neutralized predominantly their glycan-deficient variants, both in mice and humans. Binding studies with monoclonal antibodies indicated that envelope glycans reduced nAb on-rate, occupancy and thereby counteracted virus neutralization. In infected mice, the envelope glycan shield promoted protracted viral infection by preventing its timely elimination by the ensuing antibody response. Thus, arenavirus envelope glycosylation impairs the protective efficacy rather than the induction of nAbs, and thereby prevents efficient antibody-mediated virus control. This immune evasion mechanism imposes limitations on antibody-based vaccination and convalescent serum therapy. PMID:26587982
Nekoua, Magloire Pandoua; Yessoufou, Akadiri; Alidjinou, Enagnon Kazali; Badia-Boungou, Francis; Moutairou, Kabirou; Sane, Famara; Hober, Didier
2018-05-17
Enteroviruses, especially coxsackieviruses B (CV-B), have been associated with the pathogenesis of type 1 diabetes (T1D). An anti-CV-B4 neutralizing activity in saliva of T1D patients was previously reported. Our aim was to study the association between the saliva anti-CV-B4 neutralizing activity and immune parameters in T1D patients in comparison with non-diabetic individuals. Saliva and blood samples were collected from 15 T1D patients and 8 controls. The anti-CV-B4 and anti-poliovirus type 1 (PV-1) activities of saliva and serum samples were determined by a plaque neutralization assay. Quantification of serum cytokines was performed by ELISA and the frequencies of lymphocyte subsets were evaluated using flow cytometry. The levels of salivary anti-CV-B4 neutralizing activity were higher in T1D patients than in controls (p = 0.02), whereas the serum levels of anti-CV-B4 neutralizing activity and the saliva and serum levels of anti-PV-1 neutralizing activity were not different. The proportions of effector CD4 + T cells and CD19 + B cells, but not those of CD4 + T cells, CD8 + T cells and Foxp3 + regulatory T cells, were higher in T1D patients than in controls (p = 0.02 and p = 0.01 respectively). Moreover, serum IFN-γ levels were lower in T1D patients compared to controls (p = 0.03) while IL-4 and IL-10 were not different. There was an association between saliva anti-CV-B4 activity, down-regulation of IFN-γ and B cell expansion in peripheral blood of T1D patients. The association between saliva anti-CV-B4 activity and disturbance of immune system in T1D patients deserves further investigation.
Moayeri, Mahtab; Tremblay, Jacqueline M; Debatis, Michelle; Dmitriev, Igor P; Kashentseva, Elena A; Yeh, Anthony J; Cheung, Gordon Y C; Curiel, David T; Leppla, Stephen; Shoemaker, Charles B
2016-01-06
Bacillus anthracis, the causative agent of anthrax, secretes three polypeptides, which form the bipartite lethal and edema toxins (LT and ET, respectively). The common component in these toxins, protective antigen (PA), is responsible for binding to cellular receptors and translocating the lethal factor (LF) and edema factor (EF) enzymatic moieties to the cytosol. Antibodies against PA protect against anthrax. We previously isolated toxin-neutralizing variable domains of camelid heavy-chain-only antibodies (VHHs) and demonstrated their in vivo efficacy. In this work, gene therapy with an adenoviral (Ad) vector (Ad/VNA2-PA) (VNA, VHH-based neutralizing agents) promoting the expression of a bispecific VHH-based neutralizing agent (VNA2-PA), consisting of two linked VHHs targeting different PA-neutralizing epitopes, was tested in two inbred mouse strains, BALB/cJ and C57BL/6J, and found to protect mice against anthrax toxin challenge and anthrax spore infection. Two weeks after a single treatment with Ad/VNA2-PA, serum VNA2-PA levels remained above 1 μg/ml, with some as high as 10 mg/ml. The levels were 10- to 100-fold higher and persisted longer in C57BL/6J than in BALB/cJ mice. Mice were challenged with a lethal dose of LT or spores at various times after Ad/VNA2-PA administration. The majority of BALB/cJ mice having serum VNA2-PA levels of >0.1 μg/ml survived LT challenge, and 9 of 10 C57BL/6J mice with serum levels of >1 μg/ml survived spore challenge. Our findings demonstrate the potential for genetic delivery of VNAs as an effective method for providing prophylactic protection from anthrax. We also extend prior findings of mouse strain-based differences in transgene expression and persistence by adenoviral vectors. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Koen, Gerrit; van Eijk, Hetty; Koekkoek, Sylvie M.; de Jong, Menno D.; Wolthers, Katja C.
2016-01-01
Outbreaks of human enterovirus 71 (EV-71) in Asia are related to high illness and death rates among children. To gain insight into the potential threat for the population of Europe, we determined the neutralizing activity in intravenous immunoglobulin (IVIg) batches and individual serum samples from donors in the Netherlands against EV-71 strains isolated in Europe and in Asia. All IVIg batches and 41%, 79%, and 65% of serum samples from children ≤5 years of age, women of childbearing age, and HIV-positive men, respectively, showed high neutralizing activity against a Dutch C1 strain, confirming widespread circulation of EV-71 in the Netherlands. Asian B3–4 and C4 strains were efficiently cross-neutralized, predicting possible protection against extensive circulation and associated outbreaks of those types in Europe. However, C2 and C5 strains that had few mutations in the capsid region consistently escaped neutralization, emphasizing the importance of monitoring antigenic diversity among circulating EV-71 strains. PMID:27533024
Lorusso, Alessio; Baba, Doumbia; Spedicato, Massimo; Teodori, Liana; Bonfini, Barbara; Marcacci, Maurilia; Di Provvido, Andrea; Isselmou, Katia; Marini, Valeria; Carmine, Irene; Scacchia, Massimo; Di Sabatino, Daria; Petrini, Antonio; Bezeid, Beyatt Ahmed; Savini, Giovanni
2016-06-01
In March 2013, EDTA-blood and serum samples were collected from 119 cattle and 159 dromedaries at the slaughterhouse of Nouakchott, the capital city of the Islamic Republic of Mauritania. Serum samples were screened for the presence of Bluetongue (BT) antibodies by competitive ELISA (cELISA). Positive samples were then tested by serum-neutralization (SN) to determine BTV serotype. RNA from blood samples was first tested by a genus-specific quantitative RT-PCR assay which is able to detect all 27 existing BTV serotypes (RT-qPCR1-27). Positive samples were further screened by a RT-qPCR assay which, instead, is able to detect the classical 24 BTV serotypes only (RT-qPCR1-24). Of the 278 serum samples tested, 177 (mean=63.7%; 95% CI: 57.9%-69.1%) resulted positive by cELISA. Of these, 69 were from cattle (mean=58.0%; 95% CI: 49.0%-66.5%) and 108 from dromedaries (mean=67.9%; 95% CI: 60.3%-74.7%). BTV-26 neutralizing antibodies were by far the most frequently found as they were detected in 146 animals with titres ranging from 1:10 to 1:80. Out of 278 blood samples, 25 (mean=9.0%; 95% CI: 6.2%-12.9%) were found positive for BTV by RT-qPCR1-27, 20 (mean=16.8%; 95% CI: 11.2%-24.6%) were from cattle and 5 (mean=3.1%; 95% CI: 1.4%-7.1%) from dromedaries. When tested by RT-qPCR1-24 the 25 BTV positive samples were negative. Unfortunately, no genetic information by molecular typing or by next generation sequencing has been obtained as for the very low levels of RNA in the blood samples. Copyright © 2016 Elsevier B.V. All rights reserved.
Canakoglu, Nurettin; Berber, Engin; Ertek, Mustafa; Yoruk, Mustafa D; Tonbak, Sukru; Bolat, Yusuf; Aktas, Munir; Kalkan, Ahmet; Ozdarendeli, Aykut
2013-01-03
Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus of the genus Nairovirus family Bunyaviridae, which are enveloped viruses containing tripartite, negative polarity, single-stranded RNA. CCHF is characterized by high case mortality, occurring in Asia, Africa, the Middle East and Europe. Currently, there are no specific treatments or licensed vaccines available for CCHFV. Recently, two research groups have found adult mice with defective interferon responses allowed to lethal CCHFV infection. These mouse models could provide invaluable information for further studies. Efforts to develop a vaccine against CCHFV are being made. To determine the efficacy of vaccine candidates it is important to conduct serological studies that can accurately measure levels of protective antibodies. In the present study, a pseudo-plaque reduction neutralization test (PPRNT) based on enzyme-catalyzed color development of infected cells probed with anti-CCHFV antibodies was used to measure neutralization antibody of CCHFV. Sixty-nine human serum samples (20 acute and 49 convalescent) were tested. The presence of CCHFV antibodies was determined and confirmed by a commercial ELISA kit. CCHFV RNA was determined by RT-PCR. All the samples were analyzed by PPRNT and fluorescent focus reduction neutralization test (FFRNT) to measure of CCHFV-neutralizing antibodies. Pseudo-plaque reduction neutralization test showed a high sensitivity (98%), specificity (100%) and agreement (96,6%) in qualitative comparison with those of the FFRNT. There was a high correlation between the titers obtained in PPRNT and FFRNT (R2 = 0.92). The inter- and intra-assay variation of PPRNT revealed good reproducibility and positive cut-off of PPRNT was defined as 1:4 by the geometric mean titers for the individual samples distributed. The pseudo-plaque reduction neutralization test described in this study is a fast, reproducible and sensitive method for the measurement of CCHF neutralizing antibodies. This novel assay could serve as useful tools for CCHF research in epidemiology, vaccine development and other studies of immunity. It also provides an alternative to PRNT when viruses with no or poor CPE in cell culture.
2013-01-01
Background Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus of the genus Nairovirus family Bunyaviridae, which are enveloped viruses containing tripartite, negative polarity, single-stranded RNA. CCHF is characterized by high case mortality, occurring in Asia, Africa, the Middle East and Europe. Currently, there are no specific treatments or licensed vaccines available for CCHFV. Recently, two research groups have found adult mice with defective interferon responses allowed to lethal CCHFV infection. These mouse models could provide invaluable information for further studies. Efforts to develop a vaccine against CCHFV are being made. To determine the efficacy of vaccine candidates it is important to conduct serological studies that can accurately measure levels of protective antibodies. In the present study, a pseudo-plaque reduction neutralization test (PPRNT) based on enzyme-catalyzed color development of infected cells probed with anti-CCHFV antibodies was used to measure neutralization antibody of CCHFV. Methods Sixty-nine human serum samples (20 acute and 49 convalescent) were tested. The presence of CCHFV antibodies was determined and confirmed by a commercial ELISA kit. CCHFV RNA was determined by RT-PCR. All the samples were analyzed by PPRNT and fluorescent focus reduction neutralization test (FFRNT) to measure of CCHFV-neutralizing antibodies. Results Pseudo-plaque reduction neutralization test showed a high sensitivity (98%), specificity (100%) and agreement (96,6%) in qualitative comparison with those of the FFRNT. There was a high correlation between the titers obtained in PPRNT and FFRNT (R2 = 0.92). The inter- and intra-assay variation of PPRNT revealed good reproducibility and positive cut-off of PPRNT was defined as 1:4 by the geometric mean titers for the individual samples distributed. Conclusion The pseudo-plaque reduction neutralization test described in this study is a fast, reproducible and sensitive method for the measurement of CCHF neutralizing antibodies. This novel assay could serve as useful tools for CCHF research in epidemiology, vaccine development and other studies of immunity. It also provides an alternative to PRNT when viruses with no or poor CPE in cell culture. PMID:23282186
Kumar, Mukesh; O'Connell, Maile; Namekar, Madhuri; Nerurkar, Vivek R
2014-06-06
Herein we demonstrate that infection of mice with West Nile virus (WNV) Eg101 provides protective immunity against lethal challenge with WNV NY99. Our data demonstrated that WNV Eg101 is largely non-virulent in adult mice when compared to WNV NY99. By day 6 after infection, WNV-specific IgM and IgG antibodies, and neutralizing antibodies were detected in the serum of all WNV Eg101 infected mice. Plaque reduction neutralization test data demonstrated that serum from WNV Eg101 infected mice neutralized WNV Eg101 and WNV NY99 strains with similar efficiency. Three weeks after infection, WNV Eg101 immunized mice were challenged subcutaneously or intracranially with lethal dose of WNV NY99 and observed for additional three weeks. All the challenged mice were protected against disease and no morbidity and mortality was observed in any mice. In conclusion, our data for the first time demonstrate that infection of mice with WNV Eg101 induced high titers of WNV specific IgM and IgG antibodies, and cross-reactive neutralizing antibodies, and the resulting immunity protected all immunized animals from both subcutaneous and intracranial challenge with WNV NY99. These observations suggest that WNV Eg101 may be a suitable strain for the development of a vaccine in humans against virulent strains of WNV.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Johnson, John B.; Capraro, Gerald A.; Parks, Griffith D.
2008-06-20
The complement system is an important component of the innate immune response to virus infection. The role of human complement pathways in the in vitro neutralization of three closely related paramyxoviruses, Simian Virus 5 (SV5), Mumps virus (MuV) and Human Parainfluenza virus type 2 (HPIV2) was investigated. Sera from ten donors showed high levels of neutralization against HPIV2 that was largely complement-independent, whereas nine of ten donor sera were found to neutralize SV5 and MuV only in the presence of active complement pathways. SV5 and MuV neutralization proceeded through the alternative pathway of the complement cascade. Electron microscopy studies andmore » biochemical analyses showed that treatment of purified SV5 with human serum resulted in C3 deposition on virions and the formation of massive aggregates, but there was relatively little evidence of virion lysis. Treatment of MuV with human serum also resulted in C3 deposition on virions, however in contrast to SV5, MuV particles were lysed by serum complement and there was relatively little aggregation. Assays using serum depleted of complement factors showed that SV5 and MuV neutralization in vitro was absolutely dependent on complement factor C3, but was not dependent on downstream complement factors C5 or C8. Our results indicate that even though antibodies exist that recognize both SV5 and MuV, they are mostly non-neutralizing and viral inactivation in vitro occurs through the alternative pathway of complement. The implications of our work for development of paramyxovirus vectors and vaccines are discussed.« less
Kishida, Noriko; Fujisaki, Seiichiro; Yokoyama, Masaru; Sato, Hironori; Saito, Reiko; Ikematsu, Hideyuki; Xu, Hong; Takashita, Emi; Tashiro, Masato; Takao, Shinichi; Yano, Takuya; Suga, Tomoko; Kawakami, Chiharu; Yamamoto, Miwako; Kajiyama, Keiko; Saito, Hiroyuki; Shimada, Shin'ichi; Watanabe, Sumi; Aoki, Satomi; Taira, Katsuya; Kon, Miyako; Lin, Jih-Hui
2012-01-01
The vaccine strains against influenza virus A/H3N2 for the 2010-2011 season and influenza virus B for the 2009-2010 and 2010-2011 seasons in Japan are a high-growth reassortant A/Victoria/210/2009 (X-187) strain and an egg-adapted B/Brisbane/60/2008 (Victoria lineage) strain, respectively. Hemagglutination inhibition (HI) tests with postinfection ferret antisera indicated that the antisera raised against the X-187 and egg-adapted B/Brisbane/60/2008 vaccine production strains poorly inhibited recent epidemic isolates of MDCK-grown A/H3N2 and B/Victoria lineage viruses, respectively. The low reactivity of the ferret antisera may be attributable to changes in the hemagglutinin (HA) protein of production strains during egg adaptation. To evaluate the efficacy of A/H3N2 and B vaccines, the cross-reactivities of postvaccination human serum antibodies against A/H3N2 and B/Victoria lineage epidemic isolates were assessed by a comparison of the geometric mean titers (GMTs) of HI and neutralization (NT) tests. Serum antibodies elicited by the X-187 vaccine had low cross-reactivity to both MDCK- and egg-grown A/H3N2 isolates by HI test and narrow cross-reactivity by NT test in all age groups. On the other hand, the GMTs to B viruses detected by HI test were below the marginal level, so the cross-reactivity was assessed by NT test. The serum neutralizing antibodies elicited by the B/Brisbane/60/2008 vaccine reacted well with egg-grown B viruses but exhibited remarkably low reactivity to MDCK-grown B viruses. The results of these human serological studies suggest that the influenza A/H3N2 vaccine for the 2010-2011 season and B vaccine for the 2009-2010 and 2010-2011 seasons may possess insufficient efficacy and low efficacy, respectively. PMID:22492743
Rimoin, Anne W; Lu, Kai; Bramble, Matthew S; Steffen, Imke; Doshi, Reena H; Hoff, Nicole A; Mukadi, Patrick; Nicholson, Bradly P; Alfonso, Vivian H; Olinger, Gerrard; Sinai, Cyrus; Yamamoto, Lauren K; Ramirez, Christina M; Okitolonda Wemakoy, Emile; Kebela Illunga, Benoit; Pettitt, James; Logue, James; Bennett, Richard S; Jahrling, Peter; Heymann, David L; Piot, Peter; Muyembe-Tamfum, Jean Jacques; Hensley, Lisa E; Simmons, Graham
2018-01-04
The first reported outbreak of Ebola virus disease occurred in 1976 in Yambuku, Democratic Republic of Congo. Antibody responses in survivors 11 years after infection have been documented. However, this report is the first characterization of anti-Ebola virus antibody persistence and neutralization capacity 40 years after infection. Using ELISAs we measured survivor's immunological response to Ebola virus Zaire (EBOV) glycoprotein and nucleoprotein, and assessed VP40 reactivity. Neutralization of EBOV was measured using a pseudovirus approach and plaque reduction neutralization test with live EBOV. Some survivors from the original EBOV outbreak still harbor antibodies against all 3 measures. Interestingly, a subset of these survivors' serum antibodies could still neutralize live virus 40 years postinitial infection. These data provide the longest documentation of both anti-Ebola serological response and neutralization capacity within any survivor cohort, extending the known duration of response from 11 years postinfection to at least 40 years after symptomatic infection. © The Author(s) 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.
Matrix regeneration agents improve wound healing in non-stressed human corneal epithelial cells.
Robciuc, A; Arvola, R P J; Jauhiainen, M; Holopainen, J M
2018-04-01
PurposeMatrix regenerating agents (RGTAs) emerged as promising in vivo wound-healing agents. These agents could prove beneficial for the treatment of dry eye disease-associated corneal micro-erosions; therefore, we aimed to evaluate the wound healing efficacy of regenerative agents (RGTAs or serum) in an in vitro model of hyperosmolarity (HO) stressed and non-stressed human corneal epithelial cells.Patients and methodsThe migration and proliferation induced by the regenerative agents was evaluated using an in vitro scratch wound assay and brome-deoxy-uridine incorporation. The inflammatory profile and effects of osmoregulators were also investigated. The two-tailed paired t-test calculated the statistical significance, with P-value<0.05 considered significant.ResultsThe most efficient inducer of re-epithelization was 2% serum, followed closely by 2% RGTA with an average improvement in cell migration of 1.8- and 1.4-fold, respectively, when compared with the non-treated control. Hyperosmolar stress significantly reduced the restorative effects of both serum and RGTAs; these effects were, however, neutralized by the osmoregulator betaine.ConclusionThese findings suggest that RGTAs could provide efficient treatment for dry-eye associated corneal micro-lesions if ocular surface HO is neutralized.
Comparison of RFFIT tests with different standard sera and testing procedures.
Yu, Peng-cheng; Noguchi, Akira; Inoue, Satoshi; Tang, Qing; Rayner, Simon; Liang, Guo-dong
2012-06-01
The World Health Organization (WHO) standard assay for determining antibody level is the rapid fluorescent focus inhibition test (RFFIT) and is used to determine the degree of immunity after vaccination against rabies. To compare the difference in RFFIT results between the laboratories of The National Institute of Infectious Disease in Japan (NIID) and the Chinese Centre for Disease Control (CCDC) as well the influence of the choice of standard serum (STD) for the detection, the two laboratories detection methods were simultaneously manipulated by RFFIT. The reference serums used in NIID and the WHO standard serum used in CCDC were compared in the same RFFIT detection to determine the titer of four sera samples C1, S1, S2 and S4 in parallel, and the titers of the detected sera samples were calculated using the standard formula for neutralizing antibody titer. No significant difference was found in RFFIT methods from the two laboratories and the RFFIT testing procedures of the two laboratories have good consistency. However, different titers were obtained with the tentative internal standard serum (TI-STD) produced by adjusting to 2.0 IU of WHO standard serum in NIID and the WHO STD. The titer determined with the TI-STD was higher than that determined with WHO STD, This difference appears to be significant and requires further investigation.
Sonmez, Cemile; Coplu, Nilay; Gozalan, Aysegul; Akin, Lutfu; Esen, Berrin
2017-06-01
Detection of anti-tetanus antibody levels is necessary for both determination of the immune status of individuals and also for planning preventive measures. ELISA is the preferred test among in vitro tests however it can be affected by the cross reacting antibodies. A previously developed in-house ELISA test was found not reliable for the antibody levels ≤1.0IU/ml. A new method was developed to detect low antibody levels correctly. The aim of the present study was to compare the results of the newly developed in-house biotin-avidin tetanus IgG ELISA test with the in vivo mouse neutralization test, for the antibody levels ≤1.0IU/ml. A total of 54 serum samples with the antibody levels of three different levels, =0.01IU/ml, 0.01-0.1IU/ml, 0.1-1IU/ml, which were detected by in vivo mouse neutralization test were studied by the newly developed in-house biotin-avidin tetanus IgG ELISA test. Test was validated by using five different concentrations (0.01IU/ml, 0.06IU/ml, 0.2IU/ml, 0.5IU/ml, 1.0IU/ml). A statistically significant correlation (r 2 =0.9967 p=0,001) between in vivo mouse neutralization test and in-house biotin-avidin tetanus IgG ELISA test, was observed. For the tested concentrations intra-assay, inter-assay, accuracy, sensitivity, specificity and coefficients of variations were determined as ≤15%. In-house biotin-avidin tetanus IgG ELISA test can be an alternative method to in vivo mouse neutralization method for the detection of levels ≤1.0IU/ml. By using in-house biotin-avidin tetanus IgG ELISA test, individuals with non protective levels, will be reliably detected. Copyright © 2017. Published by Elsevier B.V.
Katz, J B; Hanson, S K
1987-02-01
A competitive blocking enzyme-linked immunoassay (CELIA) was developed to detect bovine viral diarrhea virus (BVDV) antibodies in undiluted fetal bovine serum (FBS). The CELIA was based on competition of serum BVDV antibodies with biotin-labelled anti-BVDV immunoglobulins (Ig) for a limited quantity of solid-phase BVDV antigen. Antigen preparation was simple, FBS could be tested undiluted, and detergent-containing washes were unnecessary. A series of dilutions of postnatal bovine BVDV antiserum prepared in FBS and a set of 147 undiluted abbatoir FBS samples were tested by both CELIA and serum neutralization tests (SNT). CELIA results on both sets of specimens correlated positively with SNT titers (r = 0.99 and r = 0.85). Relative to the SNT, CELIA sensitivity was 100%; specificity was 76%. CELIA detected a level of BVDV antibody below the 1:2-titer threshold detectable with the SNT. Advantages, limitations, and theoretical differences between the CELIA and SNT are discussed. A similar comparison of CELIA with non-competitive enzyme-linked immunoassay approaches to BVDV serodiagnosis is made. It is concluded that the CELIA is valuable in selecting only BVDV-seronegative FBS for use in virologic cell culture media.
Zika virus-like particle (VLP) based vaccine
Boigard, Hélène; Alimova, Alexandra; Martin, George R.; Katz, Al; Gottlieb, Paul
2017-01-01
The newly emerged mosquito-borne Zika virus poses a major public challenge due to its ability to cause significant birth defects and neurological disorders. The impact of sexual transmission is unclear but raises further concerns about virus dissemination. No specific treatment or vaccine is currently available, thus the development of a safe and effective vaccine is paramount. Here we describe a novel strategy to assemble Zika virus-like particles (VLPs) by co-expressing the structural (CprME) and non-structural (NS2B/NS3) proteins, and demonstrate their effectiveness as vaccines. VLPs are produced in a suspension culture of mammalian cells and self-assembled into particles closely resembling Zika viruses as shown by electron microscopy studies. We tested various VLP vaccines and compared them to analogous compositions of an inactivated Zika virus (In-ZIKV) used as a reference. VLP immunizations elicited high titers of antibodies, as did the In-ZIKV controls. However, in mice the VLP vaccine stimulated significantly higher virus neutralizing antibody titers than comparable formulations of the In-ZIKV vaccine. The serum neutralizing activity elicited by the VLP vaccine was enhanced using a higher VLP dose and with the addition of an adjuvant, reaching neutralizing titers greater than those detected in the serum of a patient who recovered from a Zika infection in Brazil in 2015. Discrepancies in neutralization levels between the VLP vaccine and the In-ZIKV suggest that chemical inactivation has deleterious effects on neutralizing epitopes within the E protein. This along with the inability of a VLP vaccine to cause infection makes it a preferable candidate for vaccine development. PMID:28481898
Healthcare Worker Seroconversion in SARS Outbreak
Ooi, Eng-Eong; Tan, Hiang-Khoon; Ong, Kong-Wee; Sil, Bijon Kumar; Teo, Melissa; Ng, Timothy; Soo, Khee-Chee
2004-01-01
Serum samples were obtained from healthcare workers 5 weeks after exposure to an outbreak of severe acute respiratory syndrome (SARS). A sensitive dot blot enzyme-linked immunosorbent assay, complemented by a specific neutralization test, shows that only persons in whom probable SARS was diagnosed had specific antibodies and suggests that subclinical SARS is not an important feature of the disease. PMID:15030691
Abutarbush, S M; La Rocca, A; Wernike, K; Beer, M; Al Zuraikat, K; Al Sheyab, O M; Talafha, A Q; Steinbach, F
2017-08-01
Schmallenberg virus (SBV)-like clinical cases of abortions in northern Jordan in early 2013, together with the emergence of SBV in Europe in 2011, its rapid spread within the following years and the detection of this virus in Turkey, raised questions about the distribution of SBV or related orthobunyaviruses. To evaluate the occurrence of SBV or related members of the Simbu serogroup of orthobunyaviruses in Jordan, bulk milk (cattle) and serum samples (cattle, sheep and goat) collected in northern Jordan in 2013 were first tested by commercially available SBV antibody ELISAs. Indeed, 3 of 47 bulk milk samples and 57 of 115 serum samples provided positive results, but SBV specificity of the ELISA results could not be confirmed by virus neutralization assays. Instead, subsequent cross-neutralization tests were able to further investigate the specificity of these antibodies. Here, a significant inhibition of Aino virus was observed. Thus, the causative agent was most likely a Simbu serogroup virus closely related to Aino virus. Consequently, these results confirm that members of this group of virus are not only present in Europe, Africa or Australia, but also in the Middle East. © 2015 Blackwell Verlag GmbH.
Hierholzer, J C; Pumarola, A
1976-01-01
An unusual variant of adenovirus (AV) 11 was isolated from throat and rectal swabs from six persons with upper respiratory illness in a Spanish military camp in March 1969. The same strain was serologically related to the upper respiratory illness of seven other men among 25 sample cases studied in detail. After strain purification, the virus was grouped as an AV by standard biological tests; it possessed the usual titers of group-specific hexon antigen but only low hemagglutinin titers (1:4 to 1:8) with erythrocytes from selected rhesus monkeys. The virus gave little reaction in hemagglutination inhibition (HI) tests with antisera to AV 1 through 35, but was neutralized to homologous titers by AV 11 antiserum. Reciprocally, rabbit and guinea pig antisera to the isolates possessed high HI antibody titers to prototype AV 14 and high serum neutralization (SN) antibody titers to prototype AV 11. On this basis, the variants were classified as AV 14-11 intermediates. Sequential serum specimens from the patients with and without positive cultures showed diagnostic rises in HI and SN antibody levels to the AV 14-11 intermediate and to prototype AV 11, but little response to AV 14. PMID:177365
Passive haemagglutination test for antibodies against rabies virus*
Gough, P. M.; Dierks, R. E.
1971-01-01
All the procedures now available for the measurement of rabies virus antibodies in serum have certain disadvantages. The serum neutralization test (SN), whether carried out by assay in mice or by the plaque-reduction technique, requires several days before the titrations are completed, necessitates special facilities for keeping large numbers of animals and tissue-culture plates, and is relatively expensive. A complement-fixation test is very insensitive, giving low titres in comparison with SN tests, and a haemagglutination-inhibition procedure is complicated by the presence of nonspecific reactions. A rabies passive haemagglutination technique (RPHA), developed to overcome many of these problems, is described. Titres obtained with human sera by the RPHA procedure correlated well with those obtained by SN tests. Both IgG and IgM classes of antibodies were measured by the RPHA procedure; however, it appeared to be more sensitive for detecting IgM than was the SN test and, therefore, gave higher titres for this class of immunoglobulins. PMID:5317009
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.
Nivarthi, Usha K.; Kose, Nurgun; Sapparapu, Gopal; Widman, Douglas; Gallichotte, Emily; Pfaff, Jennifer M.; Doranz, Benjamin J.; Weiskopf, Daniela; Sette, Alessandro; Durbin, Anna P.; Whitehead, Steve S.; Baric, Ralph
2016-01-01
ABSTRACT The four dengue virus (DENV) serotypes are mosquito-borne flaviviruses responsible for dengue fever and dengue hemorrhagic fever. People exposed to DENV develop antibodies (Abs) that strongly neutralize the serotype responsible for infection. Historically, infection with DENV serotype 4 (DENV4) has been less common and less studied than infections with the other three serotypes. However, DENV4 has been responsible for recent large and sustained epidemics in Asia and Latin America. The neutralizing antibody responses and the epitopes targeted against DENV4 have not been characterized in human infection. In this study, we mapped and characterized epitopes on DENV4 recognized by neutralizing antibodies in people previously exposed to DENV4 infections or to a live attenuated DENV4 vaccine. To study the fine specificity of DENV4 neutralizing human antibodies, B cells from two people exposed to DENV4 were immortalized and screened to identify DENV-specific clones. Two human monoclonal antibodies (MAbs) that neutralized DENV4 were isolated, and their epitopes were finely mapped using recombinant viruses and alanine scan mutation array techniques. Both antibodies bound to quaternary structure epitopes near the hinge region between envelope protein domain I (EDI) and EDII. In parallel, to characterize the serum neutralizing antibody responses, convalescence-phase serum samples from people previously exposed to primary DENV4 natural infections or a monovalent DENV4 vaccine were analyzed. Natural infection and vaccination also induced serum-neutralizing antibodies that targeted similar epitope domains at the EDI/II hinge region. These studies defined a target of neutralizing antigenic site on DENV4 targeted by human antibodies following natural infection or vaccination. IMPORTANCE The four serotypes of dengue virus are the causative agents of dengue fever and dengue hemorrhagic fever. People exposed to primary DENV infections develop long-term neutralizing antibody responses, but these principally recognize only the infecting serotype. An effective vaccine against dengue should elicit long-lasting protective antibody responses to all four serotypes simultaneously. We and others have defined antigenic sites on the envelope (E) protein of viruses of dengue virus serotypes 1, 2, and 3 targeted by human neutralizing antibodies. The epitopes on DENV4 E protein targeted by the human neutralizing antibodies and the mechanisms of serotype 4 neutralization are poorly understood. Here, we report the properties of human antibodies that neutralize dengue virus serotype 4. People exposed to serotype 4 infections or a live attenuated serotype 4 vaccine developed neutralizing antibodies that bound to similar sites on the viral E protein. These studies have provided a foundation for developing and evaluating DENV4 vaccines. PMID:28031369
Martinez, Osvaldo; Tantral, Lee; Mulherkar, Nirupama; Chandran, Kartik; Basler, Christopher F
2011-11-01
Ebola virus (EBOV) glycoprotein (GP), responsible for mediating host-cell attachment and membrane fusion, contains a heavily glycosylated mucin-like domain hypothesized to shield GP from neutralizing antibodies. To test whether the mucin-like domain inhibits the production and function of anti-GP antibodies, we vaccinated mice with Ebola virus-like particles (VLPs) that express vesicular stomatitis virus G, wild-type EBOV GP (EBGP), EBOV GP without its mucin-like domain (ΔMucGP), or EBOV GP with a Crimean-Congo hemorrhagic fever virus mucin-like domain substituted for the EBOV mucin-like domain (CMsubGP). EBGP-VLP immunized mice elicited significantly higher serum antibody titers toward EBGP or its mutants, as detected by western blot analysis, than did VLP-ΔMucGP. However, EBGP-, ΔMucGP- and CMsubGP-VLP immunized mouse sera contained antibodies that bound to cell surface-expressed GP at similar levels. Furthermore, low but similar neutralizing antibody titers, measured against a vesicular stomatitis virus (VSV) expressing EBGP or ΔMucGP, were present in EBGP, ΔMucGP, and CMsubGP sera, although a slightly higher neutralizing titer (2- to 2.5-fold) was detected in ΔMucGP sera. We conclude that the EBOV GP mucin-like domain can increase relative anti-GP titers, however these titers appear to be directed, at least partly, to denatured GP. Furthermore, removing the mucin-like domain from immunizing VLPs has modest impact on neutralizing antibody titers in serum.
Human West Nile virus infection in Bosnia and Herzegovina.
Ahmetagić, Sead; Petković, Jovan; Hukić, Mirsada; Smriko-Nuhanović, Arnela; Piljić, Dilista
2015-02-01
To describe the first two cases of West Nile virus (WNV) neuroinvasive infections in Bosnia and Herzegovina. At the Clinic for Infectious Diseases of the University Clinical Centre Tuzla, Bosnia and Herzegovina (BiH), specific screening for WNV infection was performed on patients with neuroinvasive diseases from 1 August to 31 October 2013. Serum samples were tested for the presence of WNV IgM and IgG antibodies using enzyme-linked immunosorbent assay (ELISA); positive serum samples were further analyzed by detection of WNV nucleic acid of two distinct lineages (lineage 1 and lineage 2) in sera by RT-PCR. Three (out of nine) patients met clinical criteria, and two of them had high serum titre of WNV specific IgM antibodies (3.5 and 5.2). Serum RT-PCR testing was negative. Conformation by neutralization testing was not performed. Both cases represented with encephalitis. None of these cases had recent travel history in WNW endemic areas, or history of blood transfusion and organ transplantation, so they represented autochthonous cases. Although there were no previous reports of flavivirus infections in BiH, described cases had high titre of WNV specific antibodies in serum, and negative flavivirus-vaccination history, they were defined as probable cases because recommended testing for case confirmation was not performed. The West Nile virus should be considered a possible causative pathogen in this area, probably in patients with mild influenza-like disease of unknown origin and those with neuroinvasive disease during late summer and early autumn.
Serological evidence for the presence of influenza D virus in small ruminants.
Quast, Megan; Sreenivasan, Chithra; Sexton, Gabriel; Nedland, Hunter; Singrey, Aaron; Fawcett, Linda; Miller, Grant; Lauer, Dale; Voss, Shauna; Pollock, Stacy; Cunha, Cristina W; Christopher-Hennings, Jane; Nelson, Eric; Li, Feng
2015-11-18
Influenza D virus (FLUDV) was isolated from diseased pigs with respiratory disease symptoms in 2011, and since then the new virus has also been spread to cattle. Little is known about the susceptibility of other agricultural animals and poultry to FLUDV. This study was designed to determine if other farm animals such as goats, sheep, chickens, and turkey are possible hosts to this newly emerging influenza virus. 648 goat and sheep serum samples and 250 chicken and turkey serum samples were collected from 141 small ruminant and 25 poultry farms from different geographical locations in the United States and Canada. Serum samples were examined using the hemagglutination inhibition (HI) assay and the sheep and goat samples were further analyzed using the serum neutralization assay. Results of this study showed FLUDV antibodies were detected in 13.5% (17/126) of the sampled sheep farms, and 5.2% (29/557) of tested sheep serum samples were positive for FLUDV antibodies. For the goat results, the FLUDV antibodies were detected in 13.3% (2/15) of the sampled farms, and 8.8% (8/91) of the tested goat serum samples were positive for FLUDV antibodies. Furthermore, all tested poultry serum samples were negative for FLUDV antibodies. Our data demonstrated that sheep and goat are susceptible to FLUDV virus and multiple states in U.S. have this virus infection already in these two species. This new finding highlights a need for future surveillance of FLUDV virus in small ruminants toward better understanding both the origin and natural reservoir of this new virus. Copyright © 2015 Elsevier B.V. All rights reserved.
Serum sCD30 in monitoring of alloresponse in well HLA-matched cadaveric kidney transplantations.
Matinlauri, Irma H; Kyllönen, Lauri E J; Salmela, Kaija T; Helin, Heikki; Pelzl, Steffen; Süsal, Caner
2005-12-27
In kidney transplantation, pretransplant serum sCD30 testing has been proposed in immunological risk estimation together with anti-HLA antibodies. We evaluated the risks associated with high pretransplant serum sCD30 in well HLA-matched cadaveric kidney recipients recruited in a clinical study comparing different immunosuppressive regimens. Rejection rate was similar in 37 recipients with high pretransplant serum sCD30 compared to 117 recipients with low serum sCD30 (16% vs. 15%, P=NS). Compared to pretransplant levels, the posttransplant sCD30 levels generally decreased, also in patients with rejection, although on day 21 posttransplant, rejecting patients had significantly higher relative sCD30 than nonrejecting patients (P<0.01). However, steroid-resistant rejection was associated with increasing posttransplant sCD30 levels. High pretransplant sCD30 values were associated with tubulointerstitial rejection. There was no correlation of sCD30 with delayed graft function. Good HLA matching seems to be effective in neutralizing the negative effect of a high pretransplant serum sCD30.
[Antibody responses in Japanese volunteers after immunization with yellow fever vaccine].
Taga, Kenichiro; Imura, Shunro; Hayashi, Akihiro; Kamakura, Kazumasa; Hashimoto, Satoru; Takasaki, Tomohiko; Kurane, Ichiro; Uchida, Yukinori
2002-09-01
To monitor the development of specific and cross-reactive antibody response in twenty Japanese volunteers after vaccination with live yellow fever vaccine. Serum samples were collected on various days after vaccination and examined for hemagglutination inhibition (HI) antibodies against yellow fever virus (YFV), Japanese encephalitis virus (JEV) and dengue virus (DV), neutralizing antibodies against YFV and JEV, and IgM antibodies against YFV. None of the volunteers had been previously immunized with this vaccine. Fifteen of 20 had pre-vaccinated with JEV 7 to 40 years before. Ten of the 20 had neutralizing antibodies against JEV before immunization. None of the 20 had detectable antibodies against YFV or DV before vaccination. On day 10th after the vaccination, neutralizing antibodies to YFV were detected in 6 of 19 volunteers and IgM antibodies against YFV were detected in 7 of 19. On day 14th, HI, neutralizing, and IgM antibodies against YFV were detected in all the tested sera. Neutralizing antibodies against JEV were developed in 2 volunteers and HI antibodies against JEV were increased in 3 of 6 volunteers respectively. On day 29th, cross-reactive HI antibodies for JEV and DV were detected in all the tested sera. The results indicate that YF vaccine induces YFV-specific antibodies in all the tested volunteers and that it also induces HI antibodies cross-reactive for JEV and DV. The YF vaccine has a strong immunogenicity because it is a live vaccine, and induces antibody against YFV predominantly. The international certificate of yellow fever vaccination becomes valid 10 days after vaccination. On day 14th after vaccination, we detected neutralizing antibodies against YFV from all tested volunteers, however, only 6 of 19 volunteers had detectable neutralizing antibody on the 10th day after vaccination. Therefore, the vaccine may not be perfectly effective on day 10th after the vaccination.
Leysath, Clinton E.; Ofori, Kwasi; Baldwin, Karen; Feng, Xiaochuan; Bedenice, Daniela; Webb, Robert P.; Wright, Patrick M.; Smith, Leonard A.; Tzipori, Saul; Shoemaker, Charles B.
2012-01-01
Antitoxins are needed that can be produced economically with improved safety and shelf life compared to conventional antisera-based therapeutics. Here we report a practical strategy for development of simple antitoxin therapeutics with substantial advantages over currently available treatments. The therapeutic strategy employs a single recombinant ‘targeting agent’ that binds a toxin at two unique sites and a ‘clearing Ab’ that binds two epitopes present on each targeting agent. Co-administration of the targeting agent and the clearing Ab results in decoration of the toxin with up to four Abs to promote accelerated clearance. The therapeutic strategy was applied to two Botulinum neurotoxin (BoNT) serotypes and protected mice from lethality in two different intoxication models with an efficacy equivalent to conventional antitoxin serum. Targeting agents were a single recombinant protein consisting of a heterodimer of two camelid anti-BoNT heavy-chain-only Ab VH (VHH) binding domains and two E-tag epitopes. The clearing mAb was an anti-E-tag mAb. By comparing the in vivo efficacy of treatments that employed neutralizing vs. non-neutralizing agents or the presence vs. absence of clearing Ab permitted unprecedented insight into the roles of toxin neutralization and clearance in antitoxin efficacy. Surprisingly, when a post-intoxication treatment model was used, a toxin-neutralizing heterodimer agent fully protected mice from intoxication even in the absence of clearing Ab. Thus a single, easy-to-produce recombinant protein was as efficacious as polyclonal antiserum in a clinically-relevant mouse model of botulism. This strategy should have widespread application in antitoxin development and other therapies in which neutralization and/or accelerated clearance of a serum biomolecule can offer therapeutic benefit. PMID:22238680
Mukherjee, Jean; Tremblay, Jacqueline M; Leysath, Clinton E; Ofori, Kwasi; Baldwin, Karen; Feng, Xiaochuan; Bedenice, Daniela; Webb, Robert P; Wright, Patrick M; Smith, Leonard A; Tzipori, Saul; Shoemaker, Charles B
2012-01-01
Antitoxins are needed that can be produced economically with improved safety and shelf life compared to conventional antisera-based therapeutics. Here we report a practical strategy for development of simple antitoxin therapeutics with substantial advantages over currently available treatments. The therapeutic strategy employs a single recombinant 'targeting agent' that binds a toxin at two unique sites and a 'clearing Ab' that binds two epitopes present on each targeting agent. Co-administration of the targeting agent and the clearing Ab results in decoration of the toxin with up to four Abs to promote accelerated clearance. The therapeutic strategy was applied to two Botulinum neurotoxin (BoNT) serotypes and protected mice from lethality in two different intoxication models with an efficacy equivalent to conventional antitoxin serum. Targeting agents were a single recombinant protein consisting of a heterodimer of two camelid anti-BoNT heavy-chain-only Ab V(H) (VHH) binding domains and two E-tag epitopes. The clearing mAb was an anti-E-tag mAb. By comparing the in vivo efficacy of treatments that employed neutralizing vs. non-neutralizing agents or the presence vs. absence of clearing Ab permitted unprecedented insight into the roles of toxin neutralization and clearance in antitoxin efficacy. Surprisingly, when a post-intoxication treatment model was used, a toxin-neutralizing heterodimer agent fully protected mice from intoxication even in the absence of clearing Ab. Thus a single, easy-to-produce recombinant protein was as efficacious as polyclonal antiserum in a clinically-relevant mouse model of botulism. This strategy should have widespread application in antitoxin development and other therapies in which neutralization and/or accelerated clearance of a serum biomolecule can offer therapeutic benefit.
Manalo, D L; Yamada, K; Watanabe, I; Miranda, M E G; Lapiz, S M D; Tapdasan, E; Petspophonsakul, W; Inoue, S; Khawplod, P; Nishizono, A
2017-08-01
The mass vaccination of dogs against rabies is a highly rational strategy for interrupting the natural transmission of urban rabies. According to the World Organization for Animal Health (OIE) and the World Health Organization (WHO), the immunization of at least 70% of the total dog population minimizes the risk of endemic rabies. Knowledge of the virus-neutralizing antibody (VNA) level against the rabies virus (RABV) is required to evaluate protective immunity and vaccine coverage of dogs in the field. The rapid focus fluorescent inhibition test (RFFIT) and the fluorescent antibody virus neutralization (FAVN) test are recommended by OIE and WHO to determine the VNA levels in serum. However, these tests are cell culture based and require the use of live viruses and specialized equipment. The rapid neutralizing antibody test (RAPINA) is a novel, immunochromatographic test that uses inactivated virus to estimate the VNA level qualitatively. It is a simple, rapid and inexpensive, although indirect, assay for the detection of VNA levels. The RAPINA has shown good positive and negative predictive values and a high concordance with the RFFIT results. In this study, we compared the performance of the two tests for evaluating the vaccination status of dogs in the Philippines, Thailand and Japan. A total of 1135 dog sera were analysed by the RAPINA and compared to the VNA levels determined by the RFFIT. The overall positive and negative predictive values of the RAPINA were 96.2-99.3% and 84.5-94.8%, respectively, with a concordance (kappa) of 0.946-0.97 among the three countries. The RAPINA results were highly homologous and reproducible among different laboratories. These results suggest that this test is appropriate to survey vaccination coverage in countries with limited resources. © 2016 The Authors. Zoonoses and Public Health published by Blackwell Verlag GmbH.
Narayan, Kristin M.; Agrawal, Nitish; Du, Sean X.; Muranaka, Janelle E.; Bauer, Katherine; Leaman, Daniel P.; Phung, Pham; Limoli, Kay; Chen, Helen; Boenig, Rebecca I.; Wrin, Terri; Zwick, Michael B.; Whalen, Robert G.
2013-01-01
Development of a vaccine for HIV-1 requires a detailed understanding of the neutralizing antibody responses that can be experimentally elicited to difficult-to-neutralize primary isolates. Rabbits were immunized with the gp120 subunit of HIV-1 JR-CSF envelope (Env) using a DNA-prime protein-boost regimen. We analyzed five sera that showed potent autologous neutralizing activity (IC50s at ∼103 to 104 serum dilution) against pseudoviruses containing Env from the primary isolate JR-CSF but not from the related isolate JR-FL. Pseudoviruses were created by exchanging each variable and constant domain of JR-CSF gp120 with that of JR-FL or with mutations in putative N-glycosylation sites. The sera contained different neutralizing activities dependent on C3 and V5, C3 and V4, or V4 regions located on the glycan-rich outer domain of gp120. All sera showed enhanced neutralizing activity toward an Env variant that lacked a glycosylation site in V4. The JR-CSF gp120 epitopes recognized by the sera are generally distinct from those of several well characterized mAbs (targeting conserved sites on Env) or other type-specific responses (targeting V1, V2, or V3 variable regions). The activity of one serum requires specific glycans that are also important for 2G12 neutralization and this serum blocked the binding of 2G12 to gp120. Our findings show that different fine specificities can achieve potent neutralization of HIV-1, yet this strong activity does not result in improved breadth. PMID:23326351
Nelson, Randin; Cañate, Raul; Pascale, Juan Miguel; Dragoo, Jerry W; Armien, Blas; Armien, Anibal G; Koster, Frederick
2010-09-01
Choclo virus (CHOV) was described in sigmodontine rodents, Oligoryzomys fulvescens, and humans during an outbreak of hantavirus cardiopulmonary syndrome (HCPS) in 1999-2000 in western Panama. Although HCPS is rare, hantavirus-specific serum antibody prevalence among the general population is high suggesting that CHOV may cause many mild or asymptomatic infections. The goals of this study were to confirm the role of CHOV in HCPS and in the frequently detected serum antibody and to establish the phylogenetic relationship with other New World hantaviruses. CHOV was cultured to facilitate the sequencing of the small (S) and medium (M) segments and to perform CHOV-specific serum neutralization antibody assays. Sequences of the S and M segments found a close relationship to other Oligoryzomys-borne hantaviruses in the Americas, highly conserved terminal nucleotides, and no evidence for recombination events. The maximum likelihood and maximum parsimony analyses of complete M segment nucleotide sequences indicate a close relationship to Maporal and Laguna Negra viruses, found at the base of the South American clade. In a focus neutralization assay acute and convalescent sera from six Panamanian HCPS patients neutralized CHOV in dilutions from 1:200 to 1:6,400. In a sample of antibody-positive adults without a history of HCPS, 9 of 10 sera neutralized CHOV in dilutions ranging from 1:100 to 1:6,400. Although cross-neutralization with other sympatric hantaviruses not yet associated with human disease is possible, CHOV appears to be the causal agent for most of the mild or asymptomatic hantavirus infections, as well as HCPS, in Panama.
Rehfeld, Izabelle Silva; Matos, Ana Carolina Diniz; Guedes, Maria Isabel Maldonado Coelho; Costa, Aristóteles Gomes; Fraiha, Ana Luiza Soares; Lobato, Zélia Inês Portela
2017-10-01
Bovine vaccinia (BV) is a zoonosis caused by Vaccinia virus (VACV) that mainly affects lactating cows and dairy farm milkers. The epidemiological role(s) of other cattle categories such as dry cows, bulls, and heifers in BV remains unclear. This study was performed to investigate VACV in affected dairy cattle herds and perifocal farms during an outbreak in Brazil. Crusts from lesions of cows' teats were collected from all farms with BV outbreaks. Milk, feces, blood, and serum were collected from symptomatic and asymptomatic lactating cows. Blood and serum were also sampled from other cattle categories (calves, heifers, dry cows, and bulls). The samples were tested for VACV by PCR, and to confirm VACV viability, VACV-positive samples were inoculated in BSC-40 cells and stained using immunoperoxidase. Neutralizing antibodies were investigated using plaque reduction neutralization test. Viral DNA was detected in milk, blood, and feces samples of symptomatic and asymptomatic dairy cows and in blood samples from other cattle categories on farms with and without confirmed BV outbreak. In affected farms, viable virus was identified in feces and milk samples from lactating cows and in blood samples from asymptomatic dry cows. Viable VACV was also identified in feces from lactating cows and one bull's blood sample from perifocal farms. Neutralizing antibodies were detected in 81.6% of the herds affected by BV and in 53.8% of the herds on perifocal farms. The presented data indicate a potential source of viral dissemination, which contributes to the persistence and spread of VACV in the environment. Copyright © 2017 Elsevier Ltd. All rights reserved.
West Nile virus--neutralizing antibodies in humans in Greece.
Papa, Anna; Perperidou, Parthena; Tzouli, Anisa; Castilletti, Concetta
2010-10-01
Serum samples collected during March-May 2007 from 392 residents of Imathia prefecture, Northern Greece, were tested by indirect immunofluorescence assay and enzyme-linked immunosorbent assay for IgG antibodies against West Nile virus (WNV). Microneutralization assay was applied in six positive samples. Four (4/392, 1.02%) were found positive for WNV-neutralizing antibodies. None of the positive individuals had a history of travel in endemic area or flavivirus vaccination, suggesting that WNV, or an antigenically related flavivirus, circulates in an endemic sylvatic cycle, at least locally, in rural areas in Greece. Human, animal, and vector surveillance systems have to be implemented to provide an early detection of WNV activity in Greece.
Archetti, Italo; Horsfall, Frank L.
1950-01-01
Antigenic variants of influenza A virus strains emerge on serial passage in ovo in the presence of immune serum against different but related strains. An old laboratory strain (PR8) which had been through hundreds of animal passages was as readily modified by this procedure as recently recovered strains. Such variants apparently can be obtained at will and show antigenic patterns which are reproducible and appear to be predictable in terms of the immune serum used for their selection. Variant strains retain their new antigenic patterns on serial passage in ovo in the absence of immune serum. Limited serial passage in ovo of strains in the absence of immune serum did not result in the emergence of antigenic variants. Similarly, serial passages of strains in ovo in the presence of immune serum against widely different strains, which failed to show significant cross-neutralization, did not lead to the appearance of antigenic variants. PMID:14778924
Braun, U; Bachofen, C; Schenk, B; Hässig, M; Peterhans, E
2013-05-01
The purpose of this study was to examine the occurrence of sheep persistently infected with Border disease virus (BDV) on 76 mixed cattle and sheep farms and whether seroconversion to BDV infection occurred in cattle of these farms. Seroprevalence of BDV and bovine viral disease virus (BVDV) infection in sheep was also investigated. Quantitative RT-PCR for pestivirus detection and an ELISA to detect pestivirus antibodies were used in 2'384 and 2'291 ovine blood samples, respectively. Another 27 seropositive sheep from ten flocks underwent serum neutralization testing to differentiate between BDV and BVDV antibodies. A BDV titre that was at least four times higher than the BVDV titre was interpreted as the result of BDV infection. Titres against BVDV were interpreted in an analogous fashion. All examined sheep were pestivirus-negative, 310 sheep were seropositive, 119 had an indeterminate titre and 1'862 were seronegative. The flock seroprevalence ranged from 0.0 to 73.9 %. Three of the 27 flocks that underwent serum neutralization testing were interpreted as BDV-infected because of 6 sheep with higher BDV titres, and 6 flocks were interpreted as BVDV-infected because of 14 sheep with higher BVDV titres.
Broad protection against influenza infection by vectored immunoprophylaxis in mice
Balazs, Alejandro B.; Bloom, Jesse D.; Hong, Christin M.; Rao, Dinesh S.; Baltimore, David
2014-01-01
Neutralizing antibodies that target epitopes conserved among many strains of influenza virus have been recently isolated from humans. Here we demonstrate that adeno-associated viruses (AAV) encoding two such broadly neutralizing antibodies are protective against diverse influenza strains. Serum from mice that received a single intramuscular AAV injection efficiently neutralized all H1, H2 and H5 influenza strains tested. After infection with diverse strains of H1N1 influenza, treated mice showed minimal weight loss and lung inflammation. Protection lasted for at least 11 months after AAV injection. Notably, even immunodeficient and older mice were protected by this method, suggesting that expression of a monoclonal antibody alone is sufficient to protect mice from illness. If translated to humans, this prophylactic approach may be uniquely capable of protecting immunocompromised or elderly patient populations not reliably protected by existing vaccines. PMID:23728362
Potter, Abbey; Johansen, Cheryl A; Fenwick, Stan; Reid, Simon A; Lindsay, Michael D A
2014-10-01
A serosurvey was undertaken in 15 locations in the midwest to southwest of Western Australia (WA) to investigate the seroprevalence of Ross River virus (RRV) neutralizing antibodies and factors associated with infection in western grey kangaroos (Macropus fuliginosus). The estimated seroprevalence in 2632 kangaroo samples, using a serum neutralization test, was 43.9% (95% CI 42.0, 45.8). Location was significantly associated with seroprevalence (p<0.001). There was a strong positive correlation between seroprevalence and the average log-transformed neutralizing antibody titer (r=0.98, p<0.001). The seroprevalence among adult kangaroos was significantly higher than in subadult kangaroos (p<0.05). No significant association was observed between seroprevalence and the sex of kangaroos (p>0.05). The results of this study indicate that kangaroos in WA are regularly infected with RRV and may be involved in the maintenance and transmission of RRV.
Wu, Yuling; Tabor, David E.; Mok, Hoyin; Sellman, Bret R.; Jenkins, Amy; Yu, Li; Jafri, Hasan S.; Rude, Thomas H.; Ruffin, Felicia; Schell, Wiley A.; Park, Lawrence P.; Yan, Qin; Thaden, Joshua T.; Messina, Julia A.; Esser, Mark T.
2014-01-01
Alpha-toxin is a major Staphylococcus aureus virulence factor. This study evaluated potential relationships between in vitro alpha-toxin expression of S. aureus bloodstream isolates, anti-alpha-toxin antibody in serum of patients with S. aureus bacteremia (SAB), and clinical outcomes in 100 hemodialysis and 100 postsurgical SAB patients. Isolates underwent spa typing and hla sequencing. Serum anti-alpha-toxin IgG and neutralizing antibody levels were measured by using an enzyme-linked immunosorbent assay and a red blood cell (RBC)-based hemolysis neutralization assay. Neutralization of alpha-toxin by an anti-alpha-toxin monoclonal antibody (MAb MEDI4893) was tested in an RBC-based lysis assay. Most isolates encoded hla (197/200; 98.5%) and expressed alpha-toxin (173/200; 86.5%). In vitro alpha-toxin levels were inversely associated with survival (cure, 2.19 μg/ml, versus failure, 1.09 μg/ml; P < 0.01). Both neutralizing (hemodialysis, 1.26 IU/ml, versus postsurgical, 0.95; P < 0.05) and IgG (hemodialysis, 1.94 IU/ml, versus postsurgical, 1.27; P < 0.05) antibody levels were higher in the hemodialysis population. Antibody levels were also significantly higher in patients infected with alpha-toxin-expressing S. aureus isolates (P < 0.05). Levels of both neutralizing antibodies and IgG were similar among patients who were cured and those not cured (failures). Sequence analysis of hla revealed 12 distinct hla genotypes, and all genotypic variants were susceptible to a neutralizing monoclonal antibody in clinical development (MEDI4893). These data demonstrate that alpha-toxin is highly conserved in clinical S. aureus isolates. Higher in vitro alpha-toxin levels were associated with a positive clinical outcome. Although patients infected with alpha-toxin-producing S. aureus exhibited higher anti-alpha-toxin antibody levels, these levels were not associated with a better clinical outcome in this study. PMID:25392350
Yamashita, Teruo; Ito, Miyabi; Tsuzuki, Hideaki; Sakae, Kenji; Minagawa, Hiroko
2010-04-01
Of 58 enterovirus strains isolated from Japanese travellers returning from Asian countries, eight were non-serotypable with existing antisera. By sequencing a part of the VP1 region, six of these strains were typed as echovirus 9, enterovirus (EV)-73, EV-79 or EV-97. The nucleotide identity of the VP1 region of isolate T92-1499 to all enterovirus prototypes was <70 %. The VP1 sequence of isolate TN94-0349 was closely related to coxsackievirus (CV)-A9 (73.3 % nucleotide identity), but the virus could not be neutralized with a serum raised against the prototype CV-A9 strain. On the basis of complete molecular comparisons, T92-1499 and TN94-0349 were identified as EV-98 and EV-107, respectively, by the ICTV Picornavirus Study Group. Serum neutralization tests of Japanese individuals revealed a seroprevalence rate of 11 % for EV-73, and even lower seroprevalence rates, 1.0-3.8 %, were found for the other new enteroviruses, suggesting that prior circulation of these viruses in Japan was unlikely.
Chua, Chong-Long; Sam, I-Ching; Merits, Andres; Chan, Yoke-Fun
2016-08-01
Chikungunya virus (CHIKV) is a re-emerging mosquito-borne virus which causes epidemics of fever, severe joint pain and rash. Between 2005 and 2010, the East/Central/South African (ECSA) genotype was responsible for global explosive outbreaks across India, the Indian Ocean and Southeast Asia. From late 2013, Asian genotype CHIKV has caused outbreaks in the Americas. The characteristics of cross-antibody efficacy and epitopes are poorly understood. We characterized human immune sera collected during two independent outbreaks in Malaysia of the Asian genotype in 2006 and the ECSA genotype in 2008-2010. Neutralizing capacity was analyzed against representative clinical isolates as well as viruses rescued from infectious clones of ECSA and Asian CHIKV. Using whole virus antigen and recombinant E1 and E2 envelope glycoproteins, we further investigated antibody binding sites, epitopes, and antibody titers. Both ECSA and Asian sera demonstrated stronger neutralizing capacity against the ECSA genotype, which corresponded to strong epitope-antibody interaction. ECSA serum targeted conformational epitope sites in the E1-E2 glycoprotein, and E1-E211K, E2-I2T, E2-H5N, E2-G118S and E2-S194G are key amino acids that enhance cross-neutralizing efficacy. As for Asian serum, the antibodies targeting E2 glycoprotein correlated with neutralizing efficacy, and I2T, H5N, G118S and S194G altered and improved the neutralization profile. Rabbit polyclonal antibody against the N-terminal linear neutralizing epitope from the ECSA sequence has reduced binding capacity and neutralization efficacy against Asian CHIKV. These findings imply that the choice of vaccine strain may impact cross-protection against different genotypes. Immune serum from humans infected with CHIKV of either ECSA or Asian genotypes showed differences in binding and neutralization characteristics. These findings have implications for the continued outbreaks of co-circulating CHIKV genotypes and effective design of vaccines and diagnostic serological assays.
Serological survey of antibodies against BVD virus in camels (Camelus dromedarius) in Iran.
Raoofi, Afshin; Hemmatzadeh, Farhid; Ghanaei, Amir Mansoor
2010-03-01
This serological survey was carried out to detect antibodies in dromedary camels against BVD virus in Iran. A total of 137 serum samples, were collected from camels at Khorein abattoir in suburbs of Tehran and examined for BVDV, using the serum neutralization test (SNT). Twenty seven of the 137 camels (19.7%) were positive for BVDV antibodies. It was found that the rate of seropositive camels in Iran is substantially higher compared to figures published in most other countries. This study indicated an increased frequency of infection rate with increasing age of camels. The frequency of positive cases was not significantly different between male and female camels.
Litster, A L; Pressler, B; Volpe, A; Dubovi, E
2012-08-01
Canine parvovirus (CPV) and canine distemper virus (CDV) are highly infectious and often fatal diseases with worldwide distributions, and are important population management considerations in animal shelters. A point-of-care ELISA test kit is available to detect serum antibodies to CPV and CDV, and presumptively to predict protective status. The aim of this study was to determine the diagnostic accuracy of the test compared to CPV hemagglutination inhibition titers and CDV serum neutralization titers determined by a reference laboratory, using sera collected from dogs housed at animal shelters. The ELISA test was used under both field and laboratory conditions and duplicate specimens were processed using an extra wash step. The test kit yielded accurate results (CPV: sensitivity 92.3%, specificity 93.5%; CDV: sensitivity 75.7%, specificity 91.8%) under field conditions. CDV sensitivity was improved by performing the test under laboratory conditions and using an optical density (OD) meter (laboratory performed 94.0%; OD 88.1%). Point-of-care ELISA testing for serum CPV and CDV antibody titers was demonstrated to be a useful tool for determining antibody status when making decisions regarding the need for CPV and/or CDV vaccination and also in animal shelters for population management. Copyright © 2012 Elsevier Ltd. All rights reserved.
Sun, Mingbo; Li, Changgui; Xu, Wenbo; Liao, Guoyang; Li, Rongcheng; Zhou, Jian; Li, Yanping; Cai, Wei; Yan, Dongmei; Che, Yanchun; Ying, Zhifang; Wang, Jianfeng; Yang, Huijuan; Ma, Yan; Ma, Lei; Ji, Guang; Shi, Li; Jiang, Shude; Li, Qihan
2017-05-15
A Sabin strain-based inactivated poliomyelitis vaccine (Sabin-IPV) is the rational option for completely eradicating poliovirus transmission. The neutralizing capacity of Sabin-IPV immune serum to different strains of poliovirus is a key indicator of the clinical protective efficacy of this vaccine. Sera collected from 500 infants enrolled in a randomized, blinded, positive control, phase 2 clinical trial were randomly divided into 5 groups: Groups A, B, and C received high, medium, and low doses, respectively, of Sabin-IPV, while groups D and E received trivalent oral polio vaccine and Salk strain-based IPV, respectively, all on the same schedule. Immune sera were collected after the third dose of primary immunization, and tested in cross-neutralization assays against 19 poliovirus strains of all 3 types. All immune sera from all 5 groups interacted with the 19 poliovirus strains with various titers and in a dose-dependent manner. One type 2 immunodeficiency-associated vaccine-derived poliovirus strain was not recognized by these immune sera. Sabin-IPV vaccine can induce protective antibodies against currently circulating and reference wild poliovirus strains and most vaccine-derived poliovirus strains, with rare exceptions. NCT01056705. © 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.
Jäckel, S; Eiden, M; Balkema-Buschmann, A; Ziller, M; van Vuren, P Jansen; Paweska, J T; Groschup, M H
2013-10-01
Rift Valley fever virus (RVFV) is an emerging zoonotic pathogen that causes high morbidity and mortality in humans and livestock. In this paper, we describe the cloning, expression and purification of RVFV glycoprotein Gn and its application as a diagnostic antigen in an indirect ELISA for the specific detection of RVF IgG antibodies in sheep and goats. The performance of this Gn based ELISA is validated using a panel of almost 2000 field samples from sheep and goats from Mozambique, Senegal, Uganda and Yemen. All serum samples were also tested by virus neutralization test (VNT), the gold standard method for RVFV serological testing. Compared to the VNT results the Gn based ELISA proved to have an excellent sensitivity (94.56%) and specificity (95.57%). Apart from establishing this new diagnostic assay, these results also demonstrate a close correlation between the presence of RVFV Gn and neutralizing antibodies. Copyright © 2013 Elsevier Ltd. All rights reserved.
Mimivirus Circulation among Wild and Domestic Mammals, Amazon Region, Brazil
Dornas, Fábio P.; Rodrigues, Felipe P.; Boratto, Paulo V.M.; Silva, Lorena C.F.; Ferreira, Paulo C.P.; Bonjardim, Cláudio A.; Trindade, Giliane S.; Kroon, Erna G.; La Scola, Bernard
2014-01-01
To investigate circulation of mimiviruses in the Amazon Region of Brazil, we surveyed 513 serum samples from domestic and wild mammals. Neutralizing antibodies were detected in 15 sample pools, and mimivirus DNA was detected in 9 pools of serum from capuchin monkeys and in 16 pools of serum from cattle. PMID:24564967
Ellison, Siobhan; Witonsky, Sharon
2009-07-01
Sarcocystis neurona is the principal etiologic agent of equine protozoal myeloencephalitis (EPM). An immunodominant protein of S. neurona, SnSAG-1, is expressed by the majority of S. neurona merozoites isolated from spinal tissues of horses diagnosed with EPM and may be a candidate for diagnostic tests and prophylaxis for EPM. Five horses were vaccinated with adjuvanted recombinant SnSAG1 (rSnSAG1) and 5 control (sham vaccinated) horses were vaccinated with adjuvant only. Serum was evaluated pre- and post-vaccination, prior to challenge, for antibodies against rSnSAG1 and inhibitory effects on the infectivity of S. neurona by an in vitro serum neutralization assay. The effect of vaccination with rSnSAG1 on in vivo infection by S. neurona was evaluated by challenging all the horses with S. neurona merozoites. Blinded daily examinations and 4 blinded neurological examinations were used to evaluate the presence of clinical signs of EPM. The 5 vaccinated horses developed serum and cerebrospinal fluid (CSF) titers of SnSAG1, detected by enzyme-linked immunosorbent assay (ELISA), post-vaccination. Post-vaccination serum from vaccinated horses was found to have an inhibitory effect on merozoites, demonstrated by in vitro bioassay. Following the challenge, the 5 control horses displayed clinical signs of EPM, including ataxia. While 4 of the 5 vaccinated horses did not become ataxic. One rSnSAG-1 vaccinated horse showed paresis in 1 limb with muscle atrophy. All horses showed mild, transient, cranial nerve deficits; however, disease did not progress to ataxia in rSnSAG-1 vaccinated horses. The study showed that vaccination with rSnSAG-1 produced antibodies in horses that neutralized merozoites when tested by in vitro culture and significantly reduced clinical signs demonstrated by in vivo challenge.
Ellison, Siobhan; Witonsky, Sharon
2009-01-01
Sarcocystis neurona is the principal etiologic agent of equine protozoal myeloencephalitis (EPM). An immunodominant protein of S. neurona, SnSAG-1, is expressed by the majority of S. neurona merozoites isolated from spinal tissues of horses diagnosed with EPM and may be a candidate for diagnostic tests and prophylaxis for EPM. Five horses were vaccinated with adjuvanted recombinant SnSAG1 (rSnSAG1) and 5 control (sham vaccinated) horses were vaccinated with adjuvant only. Serum was evaluated pre- and post-vaccination, prior to challenge, for antibodies against rSnSAG1 and inhibitory effects on the infectivity of S. neurona by an in vitro serum neutralization assay. The effect of vaccination with rSnSAG1 on in vivo infection by S. neurona was evaluated by challenging all the horses with S. neurona merozoites. Blinded daily examinations and 4 blinded neurological examinations were used to evaluate the presence of clinical signs of EPM. The 5 vaccinated horses developed serum and cerebrospinal fluid (CSF) titers of SnSAG1, detected by enzyme-linked immunosorbent assay (ELISA), post-vaccination. Post-vaccination serum from vaccinated horses was found to have an inhibitory effect on merozoites, demonstrated by in vitro bioassay. Following the challenge, the 5 control horses displayed clinical signs of EPM, including ataxia. While 4 of the 5 vaccinated horses did not become ataxic. One rSnSAG-1 vaccinated horse showed paresis in 1 limb with muscle atrophy. All horses showed mild, transient, cranial nerve deficits; however, disease did not progress to ataxia in rSnSAG-1 vaccinated horses. The study showed that vaccination with rSnSAG-1 produced antibodies in horses that neutralized merozoites when tested by in vitro culture and significantly reduced clinical signs demonstrated by in vivo challenge. PMID:19794889
Rubin, Steven A; Qi, Li; Audet, Susette A; Sullivan, Bradley; Carbone, Kathryn M; Bellini, William J; Rota, Paul A; Sirota, Lev; Beeler, Judy
2008-08-15
Recent mumps outbreaks in older vaccinated populations were caused primarily by genotype G viruses, which are phylogenetically distinct from the genotype A vaccine strains used in the countries affected by the outbreaks. This finding suggests that genotype A vaccine strains could have reduced efficacy against heterologous mumps viruses. The remote history of vaccination also suggests that waning immunity could have contributed to susceptibility. To examine these issues, we obtained consecutive serum samples from children at different intervals after vaccination and assayed the ability of these samples to neutralize the genotype A Jeryl Lynn mumps virus vaccine strain and a genotype G wild-type virus obtained during the mumps outbreak that occurred in the United States in 2006. Although the geometric mean neutralizing antibody titers against the genotype G virus were approximately one-half the titers measured against the vaccine strain, and although titers to both viruses decreased with time after vaccination, antibody induced by immunization with the Jeryl Lynn mumps vaccine strain effectively neutralized the outbreak-associated virus at all time points tested.
Neutralization Serotyping of BK Polyomavirus Infection in Kidney Transplant Recipients
Pastrana, Diana V.; Brennan, Daniel C.; Çuburu, Nicolas; Storch, Gregory A.; Viscidi, Raphael P.; Randhawa, Parmjeet S.; Buck, Christopher B.
2012-01-01
BK polyomavirus (BKV or BKPyV) associated nephropathy affects up to 10% of kidney transplant recipients (KTRs). BKV isolates are categorized into four genotypes. It is currently unclear whether the four genotypes are also serotypes. To address this issue, we developed high-throughput serological assays based on antibody-mediated neutralization of BKV genotype I and IV reporter vectors (pseudoviruses). Neutralization-based testing of sera from mice immunized with BKV-I or BKV-IV virus-like particles (VLPs) or sera from naturally infected human subjects revealed that BKV-I specific serum antibodies are poorly neutralizing against BKV-IV and vice versa. The fact that BKV-I and BKV-IV are distinct serotypes was less evident in traditional VLP-based ELISAs. BKV-I and BKV-IV neutralization assays were used to examine BKV type-specific neutralizing antibody responses in KTRs at various time points after transplantation. At study entry, sera from 5% and 49% of KTRs showed no detectable neutralizing activity for BKV-I or BKV-IV neutralization, respectively. By one year after transplantation, all KTRs were neutralization seropositive for BKV-I, and 43% of the initially BKV-IV seronegative subjects showed evidence of acute seroconversion for BKV-IV neutralization. The results suggest a model in which BKV-IV-specific seroconversion reflects a de novo BKV-IV infection in KTRs who initially lack protective antibody responses capable of neutralizing genotype IV BKVs. If this model is correct, it suggests that pre-vaccinating prospective KTRs with a multivalent VLP-based vaccine against all BKV serotypes, or administration of BKV-neutralizing antibodies, might offer protection against graft loss or dysfunction due to BKV associated nephropathy. PMID:22511874
Ma, Xiaoyue; Niezgoda, Michael; Blanton, Jesse D; Recuenco, Sergio; Rupprecht, Charles E
2012-08-03
Two major techniques are currently used to estimate rabies virus antibody values: neutralization assays, such as the rapid fluorescent focus inhibition test (RFFIT), and enzyme-linked immunosorbent assays (ELISAs). The RFFIT is considered the gold standard assay and has been used to assess the titer of rabies virus neutralizing antibodies for more than three decades. In the late 1970s, ELISA began to be used to estimate the level of rabies virus antibody and has recently been used by some laboratories as an alternate screening test for animal sera. Although the ELISA appears simpler, safer and more efficient, the assay is less sensitive in detecting low values of rabies virus neutralizing antibodies than neutralization tests. This study was designed to evaluate a new ELISA-based method for detecting rabies virus binding antibody. This new technique uses electro-chemi-luminescence labels and carbon electrode plates to detect binding events. In this comparative study, the RFFIT and the new ELISA-based technique were used to evaluate the level of rabies virus antibodies in human and animal serum samples. By using a conservative approximation of 0.15 IU/ml as a cutoff point, the new ELISA-based technique demonstrated a sensitivity of 100% and a specificity of 95% for human samples and for experimental animal samples. The sensitivity and specificity for field animal samples was 96% and 95%, respectively. The preliminary results from this study appear promising and demonstrate a higher sensitivity than traditional ELISA methods. Published by Elsevier Ltd.
Serologic and mucosal immune response to rotavirus infection in the rabbit model.
Conner, M E; Gilger, M A; Estes, M K; Graham, D Y
1991-01-01
We examined the humoral immune response to rotavirus infection in specific pathogen-free rabbits inoculated and challenged orally with rabbit Ala rotavirus (7.5 x 10(5) to 1 x 10(7) PFU). The humoral immune response in both serologic and mucosal samples was monitored by using total antibody enzyme-linked immunosorbent assays (ELISAs), isotype-specific ELISAs, and plaque reduction neutralization assays. Following a primary infection, all rabbits shed virus and serologic and mucosal antibody responses were initially detected by 1 week postinoculation. Intestinal immunoglobulin M was detected by 3 days postinoculation, and secretory immunoglobulin A was detected by 6 days postinoculation. Following challenge, rabbits were protected (no detectable virus shedding) from infection. An anamnestic immune response was observed only with mucosal neutralizing antibodies, and all serologic and mucosal immune responses persisted at high levels until at least 175 days postchallenge (204 days postinoculation). Detection of neutralization responses was influenced by the virus strain used in the neutralization assay; all inoculated rabbits developed detectable serum and intestinal neutralizing antibodies against the infecting (Ala) virus strain. Neutralization activity in both serum and mucosal samples was generally, but not exclusively, homotypic (VP7 serotype 3) after both primary and challenge inoculations with Ala virus. Heterotypic serum neutralization activity was observed with serotype 8 (9 of 12 rabbits) and 9 (12 of 12 rabbits) viruses and may be based on reactivity with the outer capsid protein VP4 or on a shared epitope in the C region of VP7. Comparisons of heterologous (serotype 3) and heterotypic neutralizing responses in mucosal and serologic samples revealed that 43% (21 of 49) of the responses were discordant. In 19 of 49 (39%) of these cases, a heterotypic serologic response was seen in the absence of a heterotypic mucosal response, but in 2 of 49 (4%) instances, a heterotypic mucosal response was seen in the absence of a concomitant serologic response. These results provide insight into factors which may affect detection of heterotypic responses. PMID:1850029
Respiratory Syncytial Virus (RSV): Neutralizing Antibody, a Correlate of Immune Protection.
Piedra, Pedro A; Hause, Anne M; Aideyan, Letisha
2016-01-01
Assays that measure RSV-specific neutralizing antibody activity are very useful for evaluating vaccine candidates, performing seroprevalence studies, and detecting infection. Neutralizing antibody activity is normally measured by a plaque reduction neutralization assay or by a microneutralization assay with or without complement. These assays measure the functional capacity of serum (or other fluids) to neutralize virus infectivity in cells as compared to ELISA assays that only measure the binding capacity against an antigen. This chapter discusses important elements in standardization of the RSV-specific microneutralization assay for use in the laboratory.
Xu, Weifeng; Jiang, Hao; Titsch, Craig; Haulenbeek, Jonathan R; Pillutla, Renuka C; Aubry, Anne-Françoise; DeSilva, Binodh S; Arnold, Mark E; Zeng, Jianing; Dodge, Robert W
2015-01-01
Biological therapeutics can induce an undesirable immune response resulting in the formation of anti-drug antibodies (ADA), including neutralizing antibodies (NAbs). Functional (usually cell-based) NAb assays are preferred to determine NAb presence in patient serum, but are often subject to interferences from numerous serum factors, such as growth factors and disease-related cytokines. Many functional cell-based NAb assays are essentially drug concentration assays that imply the presence of NAbs by the detection of small changes in functional drug concentration. Any drug contained in the test sample will increase the total amount of drug in the assay, thus reducing the sensitivity of NAb detection. Biotin-drug Extraction with Acid Dissociation (BEAD) has been successfully applied to extract ADA, thereby removing drug and other interfering factors from human serum samples. However, to date there has been no report to estimate the residual drug level after BEAD treatment when the drug itself is a human monoclonal antibody; mainly due to the limitation of traditional ligand-binding assays. Here we describe a universal BEAD optimization procedure for human monoclonal antibody (mAb) drugs by using a LC-MS/MS method to simultaneously measure drug (a mutant human IgG4), NAb positive control (a mouse IgG), and endogenous human IgGs as an indicator of nonspecific carry-over in the BEAD eluate. This is the first report demonstrating that residual human mAb drug level in clinical sample can be measured after BEAD pre-treatment, which is critical for further BEAD procedure optimization and downstream immunogenicity testing. Copyright © 2014 Elsevier B.V. All rights reserved.
2005-01-01
Research Center Detachment, Lima, Peru Abstract. An epitope-blocking enzyme-linked immunosorbent assay was developed for the rapid differentiation of...subtype and variety of antibodies to VEEV in equines, humans, or rodent reservoir hosts can be critical for determining the potential of a naturally...of human sera from Mexico and Peru using a blocking enzyme-linked immunosorbent assay and plaque reduction neutralization tests* Serum number Country
Variability of Venom-Neutralizing Properties of Serum from Snakes of the Colubrid Genus Lampropeltis
1992-01-01
venoms of C. atrx , S. m. bar- potentials for C s. scauhatus (type B) venom bouri, or A. c. mokasen showed persistent (Table 2). inflammation and/or edema...SMITH propeltis with these toxins would cause vascu- thality. Other workers have proposed antibody lotoxic effects. Klauber (1956) reported immu...tested, those injected with venom alone. This suggests Harvey (1960) described inhibition of C. atrx that elapid venom myolytic phospholipases Al venom
The indirect fluorescent antibody technique as a method for detecting antibodies in aborted fetuses.
Miller, R B; Wilkie, B N
1979-01-01
In this investigation the indirect fluorescent antibody technique was used to titrate antibodies in bovine sera to parainfluenza 3, infectious bovine rhinotracheitis virus and bovine viral diarrhea virus. These results were compared to those determined on the same samples by hemagglutination inhibition for parainfluenza 3 virus and serum neutralization for bovine virus diarrhea and infectious bovine rhinotracheitis virus. The results of the serological methods agreed closely. The indirect fluorescent antibody technique is a rapid and sensitive method for detecting antibodies and the procedure lends itself to use in diagnostic laboratories. In addition to the above viruses the presence or absence of antibodies to bovine coronavirus and bovine adenovirus 3 were determined by the indirect fluorescent antibody technique in thoracic fluids from 100 aborted fetuses and 50 nonaborted fetuses. Results on these samples were not compared to hemagglutination inhibition or serum neutralization as the condition of fluid samples from aborted fetuses renders interpretation of such tests unreliable. Antibodies to one or more viruses were detected in 30 of the 100 aborted fetuses and in seven of the 50 nonaborted fetuses. Antibodies to more than one agent were detected in eleven of the 100 aborted and in one of the 50 nonaborted fetuses. Reasons for this occurrence and application of the test in determination of causes of abortion are discussed. PMID:226243
Miller, Eliza; Becker, Zoe; Shalev, Daniel; Lee, Christopher T; Cioroiu, Comana; Thakur, Kiran
2017-04-15
A 55year old woman in New York City presented in May 2016 with progressive weakness, ataxia, paresthesia, and areflexia, shortly after returning from the Dominican Republic. Lumbar puncture revealed cytoalbuminological dissociation. Due to her recent travel, Zika-associated Guillain Barré syndrome (GBS) was suspected and she underwent evaluation for recent flavivirus exposure. Zika virus RNA was not detected in serum, but Zika virus immunoglobulin M (IgM) was detected in both serum and cerebrospinal fluid. Dengue virus IgM in serum was equivocal and dengue virus IgG was detected in the serum. Plaque-reduction neutralization testing showed elevated titers to both Zika virus and dengue virus, providing evidence of recent infection with a flavivirus. The patient was diagnosed with probable Zika virus-associated GBS based on clinical findings, ancillary testing, and laboratory assays according to current guidance from the Centers for Disease Control and Prevention and the Council of State and Territorial Epidemiologists. Zika virus transmission in the Americas is resulting in increasing numbers of patients presenting with Zika virus-associated neurological syndromes. Clinical and laboratory diagnosis in these cases can be challenging and may be aided by consultation with CDC, and state and local public health agencies. Copyright © 2017 Elsevier B.V. All rights reserved.
Prezoto, B C; Tanaka-Azevedo, A M; Marcelino, J R; Tashima, A K; Nishiduka, E S; Kapronezai, J; Mota, J O; Rocha, M M T; Serino-Silva, C; Oguiura, N
2018-06-15
The assessment of the capacity of antivenoms to neutralize the lethal activity of snake venoms still relies on traditional rodent in vivo lethality assay. ED 50 and LD 50 assays require large quantities of venoms and antivenoms, and besides leading to animal suffering. Therefore, in vitro tests should be introduced for assessing antivenom neutralizing capacity in intermediary steps of antivenom production. This task is facilitated when one key lethal toxin is identified. A good example is crotoxin, a β-neurotoxin phospholipase A 2 -like toxin that presents anticoagulant activity in vitro and is responsible for the lethality of venoms of Crotalus durissus snakes. By using rotational thromboelastometry, we reported recently one sensitive coagulation assay for assessing relative potency of the anti-bothropic serum in neutralizing procoagulant activity of Bothrops jararaca venom upon recalcified factor-XII-deficient chicken plasma samples (CPS). In this study, we stablished conditions for determining relative potency of four batches of the anti-crotalic serum (ACS) (antagonist) in inactivating crotoxin anticoagulant activity in CPS (target) simultaneously treated with one classical activator of coagulation (agonists). The correlation coefficient (r) between values related the ACS potency in inactivating both in vitro crotoxin anticoagulant activity and the in vivo lethality of whole venom (ED 50 ) was 0.94 (p value < 0.05). In conclusion, slowness in spontaneous thrombin/fibrin generation even after recalcification elicit time lapse sufficient for elaboration of one dose-response curve to pro- or anti-coagulant agonists in CPS. We propose this methodology as an alternative and sensitive assay for assessing antivenom neutralizing ability in plasma of immunized horses as well as for in-process quality control. Copyright © 2018 Elsevier Ltd. All rights reserved.
Serological Relationships Among Feline Caliciviruses
Povey, R. C.
1974-01-01
A total of 46 strains of feline calicivirus isolates from the United Kingdom, United States, Australia, and New Zealand were used in an investigation of their serological relationships based on the serum neutralization test. Although demonstrable antigenic variation exists between these isolates, it is shown that significant in vitro cross-activity exists between all these isolates to greater or lesser extent. All isolates tested may be regarded as serological variants of a single serotype of feline calicivirus. It is postulated that this relationship would provide for considerable cross-protection during successive exposures of cats to various feline caliciviruses. PMID:4435957
Mahon, Jennifer L; Rozanski, Elizabeth A; Paul, April L
2017-06-15
OBJECTIVE To determine the prevalence of dogs hospitalized in an intensive care unit (ICU) with serum antibody titers against canine distemper virus (CDV) and canine parvovirus (CPV). DESIGN Prospective observational study. ANIMALS 80 dogs. PROCEDURES Dogs hospitalized in an ICU for > 12 hours between February 1 and June 1, 2015, that had at least 0.25 mL of serum left over from diagnostic testing were eligible for study inclusion. Dogs with serum antibody titers > 1:32 (as determined by serum neutralization) and > 1:80 (as determined by hemagglutination inhibition) were considered seropositive for CDV and CPV, respectively. The date of last vaccination was obtained from the medical record of each dog. RESULTS Of the 80 dogs, 40 (50%) and 65 (81%) dogs were seropositive for CDV and CPV, respectively. Of the 40 dogs that were seronegative for CDV, 27 had been vaccinated against CDV within 3 years prior to testing. Of the 15 dogs that were seronegative for CPV, 3 had been vaccinated against CPV within 3 years prior to testing. Ten dogs were seronegative for both CDV and CPV. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated the prevalence of dogs hospitalized in an ICU that were seropositive for CDV and CPV was lower than expected given the high vaccination rate reported for dogs. Although the antibody titer necessary to prevent disease caused by CDV or CPV in critically ill dogs is unknown, adherence to infectious disease control guidelines is warranted when CDV- or CPV-infected dogs are treated in an ICU.
Chua, Chong-Long; Sam, I-Ching; Merits, Andres; Chan, Yoke-Fun
2016-01-01
Background Chikungunya virus (CHIKV) is a re-emerging mosquito-borne virus which causes epidemics of fever, severe joint pain and rash. Between 2005 and 2010, the East/Central/South African (ECSA) genotype was responsible for global explosive outbreaks across India, the Indian Ocean and Southeast Asia. From late 2013, Asian genotype CHIKV has caused outbreaks in the Americas. The characteristics of cross-antibody efficacy and epitopes are poorly understood. Methodology/Principal Findings We characterized human immune sera collected during two independent outbreaks in Malaysia of the Asian genotype in 2006 and the ECSA genotype in 2008–2010. Neutralizing capacity was analyzed against representative clinical isolates as well as viruses rescued from infectious clones of ECSA and Asian CHIKV. Using whole virus antigen and recombinant E1 and E2 envelope glycoproteins, we further investigated antibody binding sites, epitopes, and antibody titers. Both ECSA and Asian sera demonstrated stronger neutralizing capacity against the ECSA genotype, which corresponded to strong epitope-antibody interaction. ECSA serum targeted conformational epitope sites in the E1-E2 glycoprotein, and E1-E211K, E2-I2T, E2-H5N, E2-G118S and E2-S194G are key amino acids that enhance cross-neutralizing efficacy. As for Asian serum, the antibodies targeting E2 glycoprotein correlated with neutralizing efficacy, and I2T, H5N, G118S and S194G altered and improved the neutralization profile. Rabbit polyclonal antibody against the N-terminal linear neutralizing epitope from the ECSA sequence has reduced binding capacity and neutralization efficacy against Asian CHIKV. These findings imply that the choice of vaccine strain may impact cross-protection against different genotypes. Conclusion/Significance Immune serum from humans infected with CHIKV of either ECSA or Asian genotypes showed differences in binding and neutralization characteristics. These findings have implications for the continued outbreaks of co-circulating CHIKV genotypes and effective design of vaccines and diagnostic serological assays. PMID:27571254
Experimental milk-borne transmission of Powassan virus in the goat.
Woodall, J P; Roz, A
1977-01-01
A lactating goat with a 74-day-old kid was inoculated with 10(3) mouse 50% lethal dose (LD50) of Powassan virus. No ensuing viremia could be detected, but virus was secreted in the milk on postinoculation days 7 through 15, with a titer of 10(5) LD50/ml on day 12. Neutralizing antibody was found in the serum on days 22 through 36 and in the milk on day 36. The offspring was not inoculated but was allowed to continue feeding on its mother's milk. It developed neutralizing antibody by day 22. Since the kid was past the age when it could resorb antibody from the milk, its serum antibody was evidence of active infection. Neither animal showed any clinical sign of illness. A serum survey of 499 goats in New York State showed that 9 had neutralizing antibodies to Powassan virus. These immune goats came from widely scattered localities, including counties where human cases have been confirmed. The findings suggest the possibility of milk-borne transmission of Powassan virus from goat to man.
Messer, William B.; Yount, Boyd; Hacker, Kari E.; Donaldson, Eric F.; Huynh, Jeremy P.; de Silva, Aravinda M.; Baric, Ralph S.
2012-01-01
Dengue viruses (DENV) are enveloped single-stranded positive-sense RNA viruses transmitted by Aedes spp. mosquitoes. There are four genetically distinct serotypes designated DENV-1 through DENV-4, each further subdivided into distinct genotypes. The dengue scientific community has long contended that infection with one serotype confers lifelong protection against subsequent infection with the same serotype, irrespective of virus genotype. However this hypothesis is under increased scrutiny and the role of DENV genotypic variation in protection from repeated infection is less certain. As dengue vaccine trials move increasingly into field-testing, there is an urgent need to develop tools to better define the role of genotypic variation in DENV infection and immunity. To better understand genotypic variation in DENV-3 neutralization and protection, we designed and constructed a panel of isogenic, recombinant DENV-3 infectious clones, each expressing an envelope glycoprotein from a different DENV-3 genotype; Philippines 1982 (genotype I), Thailand 1995 (genotype II), Sri Lanka 1989 and Cuba 2002 (genotype III) and Puerto Rico 1977 (genotype IV). We used the panel to explore how natural envelope variation influences DENV-polyclonal serum interactions. When the recombinant viruses were tested in neutralization assays using immune sera from primary DENV infections, neutralization titers varied by as much as ∼19-fold, depending on the expressed envelope glycoprotein. The observed variability in neutralization titers suggests that relatively few residue changes in the E glycoprotein may have significant effects on DENV specific humoral immunity and influence antibody mediated protection or disease enhancement in the setting of both natural infection and vaccination. These genotypic differences are also likely to be important in temporal and spatial microevolution of DENV-3 in the background of heterotypic neutralization. The recombinant and synthetic tools described here are valuable for testing hypotheses on genetic determinants of DENV-3 immunopathogenesis. PMID:22389731
Amexis, Georgios; Young, Neal S
2006-09-15
For the production of dengue-vaccine candidates, empty capsids, or virus-like particles (VLPs), of parvovirus B19 that carry dengue 2-specific epitopes were employed as antigen carriers. Two epitopes (comprising amino acids 352-368 and 386-397) of domain BIII of the envelope glycoprotein were chosen to produce recombinant B19 VLPs for immunization of BALB/c mice. Serum samples from immunized mice revealed that recombinant B19 VLPs elicited strong humoral immune responses. In summary, this B19 VLP-vaccine platform produced high (> or =2.0 x 10(5)) anti-dengue 2 titers and robust (< or =1 120) 50%-plaque-reduction neutralization test (PRNT(50)) titers, which effectively neutralized live dengue 2 virus in PRNT(50) assays.
A guinea pig model of Zika virus infection.
Kumar, Mukesh; Krause, Keeton K; Azouz, Francine; Nakano, Eileen; Nerurkar, Vivek R
2017-04-11
Animal models are critical to understand disease and to develop countermeasures for the ongoing epidemic of Zika virus (ZIKV). Here we report that immunocompetent guinea pigs are susceptible to infection by a contemporary American strain of ZIKV. Dunkin-Hartley guinea pigs were inoculated with 10 6 plaque-forming units of ZIKV via subcutaneous route and clinical signs were observed. Viremia, viral load in the tissues, anti-ZIKV neutralizing antibody titer, and protein levels of multiple cytokine and chemokines were analyzed using qRT-PCR, plaque assay, plaque reduction neutralization test (PRNT) and multiplex immunoassay. Upon subcutaneous inoculation with PRVABC59 strain of ZIKV, guinea pigs demonstrated clinical signs of infection characterized by fever, lethargy, hunched back, ruffled fur, and decrease in mobility. ZIKV was detected in the whole blood and serum using qRT-PCR and plaque assay. Anti-ZIKV neutralizing antibody was detected in the infected animals using PRNT. ZIKV infection resulted in a dramatic increase in protein levels of multiple cytokines, chemokines and growth factors in the serum. ZIKV replication was observed in spleen and brain, with the highest viral load in the brain. This data demonstrate that after subcutaneous inoculation, the contemporary ZIKV strain is neurotropic in guinea pigs. The guinea pig model described here recapitulates various clinical features and viral kinetics observed in ZIKV-infected patients, and therefore may serve as a model to study ZIKV pathogenesis, including pregnancy outcomes and for evaluation of vaccines and therapeutics.
Ma, Yan; Qin, Min; Hu, Hui-Qiong; Ji, Guang; Feng, Ling; Gao, Na; Gu, Jie; Xie, Bing-Feng; He, Ji-Hong; Sun, Ming-Bo
2011-06-01
In order to search the preparation process and optimazing dosage ratio of adsorbed diphtheria-tetanus-acellular pertussis and sabin inactivated poliovirus combined vaccine (DTaP-sIPV), the neutralizing antibody titers of IPV induced by different concentration of DTaP-sIPV were investigated on rats. Two batches of DTaP-sLPV were produced using different concentration of sIPV and the quality control was carried. Together with sabin-IPV and DTaP-wIPV ( boostrix-polio, GSK, Belgium) as control group, the DTaP-sIPV were administrated on three-dose schedule at 0, 1, 2 month on rats. Serum sample were collected 30 days after each dose and neutralizing antibody titers against three types poliovirus were determined using micro-neutralization test. Two batches of prepared DTaP-sIPV and control sLPV were according to the requirement of Chinese Pharmacopoeia (Volume III, 2005 edition) and showed good stability. The seropositivity rates were 100% for sabin inactivated poliovirus antigen in all groups. The GMTs (Geometric mean titers) of neutralizing antibodies against three types poliovirus increased. The prepared DTaP-sIPV was safe, stable and effective and could induced high level neutralizing antibody against poliovirus on rats.
Ratti, H; Zhang, M; Kunkel, G
2001-03-02
Neutral endopeptidase (NEP) is described in airways as the major degrading enzyme of tachykinins such as neurokinin A (NKA) and substance P (SP). Due to its localization and mode of action NEP may play a role in the pathophysiology of bronchial reactivity (BR) especially under the aspect of neurogenic inflammation. Serum NEP concentrations were measured by ELISA to investigate if there is a correlation between serum NEP and the degree of bronchial reactivity expressed by PC20-FEV1 histamine(.). PC20-FEV1 histamine was determined in 31 asthmatic patients [age 31.9+/-1.3 years (mean+/-SEM) FEV1=92.1+/-2.4% (mean+/-SEM) 16 females/15 males]. Prior to the histamine challenge blood samples were obtained and stored at -70 degrees C until determination using ELISA. A significant correlation between serum NEP and the PC20-FEV1 (n=31, r=0.49, P<0.01) was found. The results suggest that serum NEP is modulating neuropeptide-induced effects in the pathophysiology of airway responsiveness.
BK Polyomavirus Genotypes Represent Distinct Serotypes with Distinct Entry Tropism
Pastrana, Diana V.; Ray, Upasana; Magaldi, Thomas G.; Schowalter, Rachel M.; Çuburu, Nicolas
2013-01-01
BK polyomavirus (BKV) causes significant urinary tract pathogenesis in immunosuppressed individuals, including kidney and bone marrow transplant recipients. It is currently unclear whether BKV-neutralizing antibodies can moderate or prevent BKV disease. We developed reporter pseudoviruses based on seven divergent BKV isolates and performed neutralization assays on sera from healthy human subjects. The results demonstrate that BKV genotypes I, II, III, and IV are fully distinct serotypes. While nearly all healthy subjects had BKV genotype I-neutralizing antibodies, a majority of subjects did not detectably neutralize genotype III or IV. Surprisingly, BKV subgenotypes Ib1 and Ib2 can behave as fully distinct serotypes. This difference is governed by as few as two residues adjacent to the cellular glycan receptor-binding site on the virion surface. Serological analysis of mice given virus-like particle (VLP)-based BKV vaccines confirmed these findings. Mice administered a multivalent VLP vaccine showed high-titer serum antibody responses that potently cross-neutralized all tested BKV genotypes. Interestingly, each of the neutralization serotypes bound a distinct spectrum of cell surface receptors, suggesting a possible connection between escape from recognition by neutralizing antibodies and cellular attachment mechanisms. The finding implies that different BKV genotypes have different cellular tropisms and pathogenic potentials in vivo. Individuals who are infected with one BKV serotype may remain humorally vulnerable to other BKV serotypes after implementation of T cell immunosuppression. Thus, prevaccinating organ transplant recipients with a multivalent BKV VLP vaccine might reduce the risk of developing posttransplant BKV disease. PMID:23843634
Kellner, Aaron; Freeman, Elizabeth B.; Carlson, Arthur S.
1958-01-01
Specific neutralizing antibodies directed against streptococcal DPNase were induced experimentally in rabbits and guinea pigs by the injection of partially purified preparations of the enzyme. Similar antibodies capable of inhibiting the biological activity of the enzyme were found to occur naturally in the serum of a very high percentage of human beings, and the titer of these antibodies often rose sharply following streptococcal infections. The antibody response to streptococcal DPNase in general paralleled that to streptolysin O, though in some instances antibodies to one increased when those to the other did not. PMID:13575667
Kading, Rebekah C; Borland, Erin M; Cranfield, Mike; Powers, Ann M
2013-07-01
Vector-borne and zoonotic pathogens have comprised a significant proportion of the emerging infectious diseases in humans in recent decades. The role of many wildlife species as reservoirs for arthropod-borne viral pathogens is poorly understood. We investigated the exposure history of various African wildlife species from the Congo basin to mosquito-borne flaviviruses and alphaviruses by testing archived serum samples. Sera from 24 African forest buffalo (Syncerus caffer nanus), 34 African elephants (Loxodonta africana), 40 duikers (Cephalophus and Philantomba spp.), 25 mandrills (Mandrillus sphinx), 32 mountain gorillas (Gorilla beringei beringei), five Grauer's gorillas (Gorilla beringei graueri), two L'Hoest's monkeys (Cercopithecus lhoesti), two golden monkeys (Cercopithecus kandti), and three chimpanzees (Pan troglodytes) sampled between 1991 and 2009 were tested for antibodies against chikungunya virus (CHIKV), o'nyong-nyong virus (ONNV), West Nile virus (WNV), dengue 2 virus (DENV-2), and yellow fever virus (YFV) by plaque reduction neutralization test. Specific neutralizing antibodies against ONNV were found in African forest buffalo in the Democratic Republic of the Congo (DRC) and Gabon, duikers in the DRC, and mandrills in Gabon, providing novel evidence of enzootic circulation of ONNV in these countries. African forest buffalo in the DRC and Gabon also demonstrated evidence of exposure to CHIKV, WNV, and DENV-2, while mandrills in Gabon were antibody positive for CHIKV, DENV-2, WNV, and YFV. All of the elephants tested had a strong neutralizing antibody response to WNV. We also document results from a survey of gorillas for arboviruses, of which 4/32 (13%) had antibody to an alphavirus or flavivirus. Overall, our results demonstrate a high prevalence of neutralizing antibodies against multiple arboviruses in wildlife in equatorial Africa.
Bauermann, Fernando V; Flores, Eduardo F; Falkenberg, Shollie M; Weiblen, Rudi; Ridpath, Julia F
2014-01-01
The detection of an emerging pestivirus species, "HoBi-like virus," in fetal bovine serum (FBS) labeled as U.S. origin, but packaged in Europe, raised concerns that HoBi-like virus may have entered the United States. In the current study, 90 lots of FBS originating in North America (NA) were screened for pestivirus antigen and antibodies. Lots in group 1 (G1, 72 samples) and group 2 (G2, 9 samples) originated in NA and were packaged in the United States. Group 3 (G3) was composed of 9 lots collected in NA and processed in Europe. Lots in G1 were claimed negative for Bovine viral diarrhea virus (BVDV), while lots in G2 and G3 were claimed positive by the commercial processor. All lots in G1 and G2 tested negative by reverse transcription polymerase chain reaction (RT-PCR) using HoBi-like-specific primers. Two G1 lots tested positive by BVDV RT-PCR. One of these was also positive by virus isolation. All G2 lots were positive by BVDV RT-PCR. In addition, four G2 lots were VI positive while 1 lot was antigen-capture enzyme-linked immunosorbent assay (ELISA) positive. Two G3 lots were positive by HoBi-like-specific RT-PCR tests. All lots were negative for HoBi_D32/00 neutralizing antibodies. Seven lots (4 G1; 1 G2; 2 G3) had antibodies against BVDV by virus neutralization and/or antigen-capture ELISA. While there is no evidence of HoBi-like viruses in NA based on tested samples, further studies are required to validate HoBi-like virus-free status and develop means to prevent the spread of HoBi-like virus into NA.
Lindsey, Changhong Y; Brown, J Edward; Torabazar, Nahid R; Smith, Leonard A
2013-01-01
A recombinant ricin toxin A-chain 1-33/44-198 vaccine (RVEc), developed at the United States Army Medical Research Institute of Infectious Diseases as a vaccine candidate, is under investigation in a phase 1 clinical study. To effectively evaluate the immunogenicity of this ricin vaccine and to eliminate the use of radioactive material, an EL4 cell-based colorimetric toxin neutralization activity (TNA) assay using a CellTiter 96 AQueous One Solution Cell Proliferation Assay Reagent has been developed, optimized, and applied in the vaccine efficacy studies. The TNA assay measures the protective neutralizing anti-ricin antibodies in animal sera by determining the cell viability after ricin exposure in the assay system and comparing it to a purified mouse polyclonal antiricin IgG standard curve. The standard curve of the anti-ricin TNA assay closely fits a four-parameter logistic regression model. The unknown test sample concentration was expressed as microg/mL, but not the 50% effective concentration (EC50), which was determined by most TNA assays. The neutralizing endpoint titers, not the 50% effective dilution (ED50), of human specimens were measured with the TNA assay in support of the clinical study of the RVEc vaccine. The optimal amount of ricin toxin, EL4 cells, and concentration of standards used in the assay system was established to minimize false-negative and false-positive results of serum specimens from the nonclinical and clinical studies of RVEc. The testing conditions were adjusted to optimize assay performance. The colorimetric TNA assay replaced a radioactive TNA assay previously used in the ricin vaccine studies.
Avian influenza H9N2 seroprevalence among pig population and pig farm staff in Shandong, China.
Li, Song; Zhou, Yufa; Zhao, Yuxin; Li, Wenbo; Song, Wengang; Miao, Zengmin
2015-03-01
Shandong province of China has a large number of pig farms with the semi-enclosed houses, allowing crowds of wild birds to seek food in the pig houses. As the carriers of avian influenza virus (AIV), these wild birds can easily pass the viruses to the pigs and even the occupational swine-exposed workers. However, thus far, serological investigation concerning H9N2 AIV in pig population and pig farm staff in Shandong is sparse. To better understand the prevalence of H9N2 AIV in pig population and pig farm staff in Shandong, the serum samples of pigs and occupational pig-exposed workers were collected and tested for the antibodies for H9N2 AIV by both hemagglutination inhibition (HI) and micro-neutralization (MN) assays. When using the antibody titers ≥40 as cut-off value, 106 (HI: 106/2176, 4.87%) and 84 (MN: 84/2176, 3.86%) serum samples of pigs were tested positive, respectively; 6 (HI: 6/287, 2.09%) and 4 (MN: 4/287, 1.39%) serum samples of the pig farm staff were positive, respectively; however, serum samples from the control humans were tested negative in both HI and MN assays. These findings revealed that there were H9N2 AIV infections in pig population and pig farm staff in Shandong, China. Therefore, it is of utmost importance to conduct the long-term surveillance of AIV in pig population and the pig farm staff.
Twark, L; Dodds, W J
2000-10-01
To assess whether serum canine parvovirus (CPV) and canine distemper virus (CDV) antibody titers can be used to determine revaccination protocols in healthy dogs. Case series. 1,441 dogs between 6 weeks and 17 years old. CPV and CDV antibody titers in serum samples submitted to a commercial diagnostic laboratory were measured by use of indirect fluorescent antibody (IFA) tests. On the basis of parallel measurements of CPV and CDV serum antibody titers in 61 paired serum samples determined by use of hemagglutination inhibition and serum neutralization methods, respectively, we considered titers > or = 1:5 (IFA test) indicative of an adequate antibody response. Age, breed, and sex were not significantly associated with adequate CPV- or CDV-specific antibody responses. Of 1,441 dogs, 1,370 (95.1%) had adequate and 71 (4.9%) had inadequate antibody responses to CPV, whereas 1,346 of 1,379 (97.6%) dogs had adequate and 33 (2.4%) had inadequate responses to CDV. Vaccination histories were available for 468 dogs (468 for CPV, 457 for CDV). Interval between last vaccination and antibody measurement was 1 to 2 years for the majority (281/468; 60.0%) of dogs and 2 to 7 years for 142 of 468 (30.3%) dogs. Interval was < 1 year in only 45 of 468 (9.6%) dogs. The high prevalence of adequate antibody responses (CPV, 95.1%; CDV, 97.6%) in this large population of dogs suggests that annual revaccination against CPV and CDV may not be necessary.
Jin, Shupei; Qiao, Yinghua; Xing, Jun
2018-06-01
In this study, a ternary mixed-mode silica sorbent (TMSS) with octamethylene, carboxyl, and amino groups was prepared via Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click reaction and a subsequent reduction of azide to primary amine. While used in solid-phase extraction (SPE), the retention behavior of TMSS towards a total of nine kinds of basic, neutral, and acidic drugs was investigated in detail. The results revealed that hydrophobic, ion-exchange interaction, and electrostatic repulsion between TMSS and the analytes were closely related to the retention behavior of TMSS. Besides, the log K ow value of the analyte was also a factor influencing the retention behavior of analytes on TMSS. The nine analytes could be retained by TMSS simultaneously and then, were eluted into two fractions according to the acid-base property of the analytes for further determinations. The acidic and neutral analytes were in one fraction, and the basic ones in the other fraction. When used to treat the human serum spiked with the nine drugs, TMSS offered higher recoveries than BakerBond CBA and comparable recoveries to Oasis WCX. It should be noted TMSS had better purifying capability for human serum than Oasis WCX. Under the optimized SPE conditions, a method of SPE hyphenated to high-performance liquid chromatography-ultraviolet detection (HPLC-UV) for determination of the basic, neutral, and acidic drugs spiked in human serum was established. For the nine drugs, the linear ranges were all between 5.0 and 1000 μg L -1 with correlation coefficients (R 2 ) above 0.9990, and the limits of detection (LODs) were in the range of 0.8-2.3 μg L -1 . The intra-day and inter-day relative standard deviations (RSDs) were less than 5.3 and 8.8%, respectively. Graphical abstract Treating drugs in human serum by SPE with ternary mixed-mode silica sorbent.
LeDuc, J W; Ksiazek, T G; Rossi, C A; Dalrymple, J M
1990-11-01
More than 600 sera from 245 patients with a clinical diagnosis of hemorrhagic fever were preserved by the Hemorrhagic Fever Commission during the Korean Conflict, 1951-1954. These sera were tested for IgM- and IgG-specific antibodies to Hantaan virus by enzyme immunoassay and for hantaviral antigen by immunoassay; one serum from each patient was tested by plaque reduction neutralization using both Hantaan and Seoul viruses. Only 15 patients failed to develop antihantaviral antibodies; most sera contained high titered IgM antibody on admission, and all were IgM-seropositive by day 7 after onset. Attempts to detect hantaviral antigen were unsuccessful. All seropositive patients had highest plaque reduction neutralization titers to Hantaan virus, suggesting that this virus was responsible for the disease seen. These results confirm that hemorrhagic fever of the Korean Conflict was due to Hantaan virus and demonstrate that measurement of specific IgM antibody is the method of choice for diagnosis of acute disease.
Broad and potent HIV-1 neutralization by a human antibody that binds the gp41-120 interface
Huang, Jinghe; Kang, Byong H.; Pancera, Marie; Lee, Jeong Hyun; Tong, Tommy; Feng, Yu; Georgiev, Ivelin S.; Chuang, Gwo-Yu; Druz, Aliaksandr; Doria-Rose, Nicole A.; Laub, Leo; Sliepen, Kwinten; van Gils, Marit J.; de la Peña, Alba Torrents; Derking, Ronald; Klasse, Per-Johan; Migueles, Stephen A.; Bailer, Robert T.; Alam, Munir; Pugach, Pavel; Haynes, Barton F.; Wyatt, Richard T.; Sanders, Rogier W.; Binley, James M.; Ward, Andrew B.; Mascola, John R.; Kwong, Peter D.; Connors, Mark
2014-01-01
The isolation of human monoclonal antibodies (mAbs) is providing important insights regarding the specificities that underlie broad neutralization of HIV-1 (reviewed in1). Here we report a broad and extremely potent HIV-specific mAb, termed 35O22, which binds novel HIV-1 envelope glycoprotein (Env) epitope. 35O22 neutralized 62% of 181 pseudoviruses with an IC50<50 μg/ml. The median IC50 of neutralized viruses was 0.033 μg/ml, among the most potent thus far described. 35O22 did not bind monomeric forms of Env tested, but did bind the trimeric BG505 SOSIP.664. Mutagenesis and a reconstruction by negative-stain electron microscopy of the Fab in complex with trimer revealed it to bind a conserved epitope, which stretched across gp120 and gp41. The specificity of 35O22 represents a novel site of vulnerability on HIV Env, which serum analysis indicates to be commonly elicited by natural infection. Binding to this new site of vulnerability may thus be an important complement to current mAb-based approaches to immunotherapies, prophylaxis, and vaccine design. PMID:25186731
Nara, P L; Smit, L; Dunlop, N; Hatch, W; Merges, M; Waters, D; Kelliher, J; Gallo, R C; Fischinger, P J; Goudsmit, J
1990-01-01
Emergence in two chimpanzees of human immunodeficiency virus type 1 (HIV-1) IIIB variants resistant to neutralization by the preexisting antibody is described. Viruses isolated from the HIV-1 IIIB gp120-vaccinated and -challenged animal were more resistant to neutralization by the chimpanzee's own serum than viruses isolated from the naive infected animal, indicating immune pressure as the selective mechanism. However, all reisolated viruses were 16- to 256-fold more neutralization resistant than the inoculum virus to antibodies binding to the third variable domain (V3) of the HIV-1 external envelope. Early chimpanzee serum samples that neutralized the inoculum strain but not the reisolated viruses were found to bind an HIV-1 IIIB common nonapeptide (IQRGPGRAF) derived from the gp120 isolate-specific V3 domain shown to induce isolate-specific neutralization in other animals. Amplification of the V3 coding sequence by polymerase chain reaction and subsequent sequence analysis of the neutralization-resistant variants obtained from in vivo-infected animals indicated that early resistance to neutralization by an HIV-1 IIIB monoclonal antibody (0.5 beta) was conferred by changes outside the direct binding site for the selective neutralizing antibody. The reisolated neutralization-resistant isolates consisted of the lower-replication-competent virus subpopulations of the HIV-1 IIIB stock, as confirmed by biological and sequence analyses. In vitro passage of the HIV-1 IIIB stock through chimpanzee and human peripheral blood mononuclear cell cultures void of HIV-specific antibody resulted in homogenic amplification of the more-replication-competent subpopulation preexisting in the original viral stock, suggesting a role for the immune system in suppressing the more-replication-competent viruses. Images PMID:2370681
Hyde, R L
1986-01-01
Efforts are being made at the National Veterinary Services Laboratories to reduce in vivo testing of USDA licensed veterinary vaccines. A hemagglutination test for determining potency of killed parvovirus vaccine is currently being used for canine and swine adjuvanted and nonadjuvanted products; a serum neutralization inhibition test (SNIT) is being developed for potency testing of killed adjuvanted infectious bovine rhinotracheitis (IBR), bovine virus diarrhea (BVD) and parainfluenza (PI3) vaccines: and a tissue culture titration method for live avian encephalomyelitis virus vaccine is being pursued as a replacement for the old hatch-out chick embryo titration method. Difficulties in separating the antigen from oil emulsion products are preventing significant advances in developing in vitro testing procedures for poultry killed-virus vaccines.
Liang, Cheng-Zhu; Cao, Rui-Bing; Wei, Jian-Chao; Zhu, Lai-Hua; Chen, Pu-Yan
2006-06-01
According to the antigenic analysis of equine arteritis virus (EAV) GL protein, one pair of primers were designed, with which the gene fragment coding the high antigenic domain of EAV GL protein was amplified from the EAV genome. The cloned gene was digested with BamH I and Xho I and then inserted into pET-32a and resulted pET-GL1. The pET-GL1 was transformed into the host cell BL21(DE3) and the expression was optimized including cultivation temperature and concentration of IPTG. The aim protein was highly expressed and the obtained recombinant protein manifested well reactiongenicity as was confirmed by Western blot. The recombinant GL1 protein was purified by the means of His * Bind resin protein purification procedure. Then an indirect ELISA was established to detect antibody against EAV with the purified GL1 protein as the coating antigen. The result showed that the optimal concentration of coated antigen was 9.65 microg/mL and the optimal dilution of serum was 1:80. The positive criterion of this ELISA assay is OD (the tested serum) > 0.4 and OD (the tested serum) /OD (the negative serum) > 2.0. The iGL-ELISA was evaluated versus micro-virus neutralization test. The ELISA was performed on 900 sera from which were preserved by this lab during horse entry/exit inspection, the agreement (94.1%) of these test were considered suitable for individual serological detection. In another test which 180 sera samples were detected by iGL-ELISA and INGEZIM ELISA kit respectively. The agreement ratio between the two methods is 95.6%.
Gouma, Sigrid; Ten Hulscher, Hinke I; Schurink-van 't Klooster, Tessa M; de Melker, Hester E; Boland, Greet J; Kaaijk, Patricia; van Els, Cécile A C M; Koopmans, Marion P G; van Binnendijk, Rob S
2016-07-29
Similar to other recent mumps genotype G outbreaks worldwide, most mumps patients during the recent mumps genotype G outbreaks in the Netherlands had received 2 doses of measles, mumps and rubella (MMR) vaccine during childhood. Here, we investigate the capacity of vaccine-induced antibodies to neutralize wild type mumps virus strains, including mumps virus genotype G. In this study, we tested 105 pre-outbreak serum samples from students who had received 2 MMR vaccine doses and who had no mumps virus infection (n=76), symptomatic mumps virus infection (n=10) or asymptomatic mumps virus infection (n=19) during the mumps outbreaks. In all samples, mumps-specific IgG concentrations were measured by multiplex immunoassay and neutralization titers were measured against the Jeryl Lynn vaccine strain and against wild type genotype G and genotype D mumps virus strains. The correlation between mumps-specific IgG concentrations and neutralization titers against Jeryl Lynn was poor, which suggests that IgG concentrations do not adequately represent immunological protection against mumps virus infection by antibody neutralization. Pre-outbreak neutralization titers in infected persons were significantly lower against genotype G than against the vaccine strain. Furthermore, antibody neutralization of wild type mumps virus genotype G and genotype D was significantly reduced in pre-outbreak samples from infected persons as compared with non-infected persons. No statistically significant difference was found for the vaccine strain. The sensitivity/specificity ratio was largest for neutralization of the genotype G strain as compared with the genotype D strain and the vaccine strain. The reduced neutralization of wild type mumps virus strains in MMR vaccinated persons prior to infection indicates that pre-outbreak mumps virus neutralization is partly strain-specific and that neutralization differs between infected and non-infected persons. Therefore, we recommend the use of wild type mumps virus neutralization assays as preferred tool for surveillance of protection against mumps virus infection. Copyright © 2016 Elsevier Ltd. All rights reserved.
El Hage, J; Lorusso, A; Carmine, I; Di Gennaro, A; Portanti, O; Olivieri, S; Casaccia, C; Pisciella, M; Teodori, L; Sghaier, S; Savini, G
2013-10-01
Since 2000, several incursions of bluetongue virus (BTV) occurred in the Mediterranean Basin involving European and surrounding Countries. The Middle East represents one of the most important gateways for the access of BTV in Europe. Limited data on the BTV situation in this area are available. In this perspective, an epidemiological survey on the presence of BTV in Lebanon was conducted. Of the 181 serum samples tested, 97 (mean = 53.6%; 95% CI: 46.3-60.7) resulted positive when tested for the presence of BTV antibodies by c-ELISA, of these 42 (mean = 42%; 95% CI: 32.8-51.8) serum samples were from sheep and 55 (mean = 67.9%; 95% CI: 57.1-77.1) serum samples were from goats. Fourteen blood samples (14/110; mean = 12.7%; 95% CI: 7.8-20.3), 6 (6/66; mean = 9.1%; 95% CI: 4.4-18.5) from sheep and 8 (8/44; mean = 18.2%; 95% CI: 9.6-32.0) from goats, were positive by qRT-PCR. The results with serum-neutralization assay and typing performed by RT-PCR confirmed that six BTV serotypes are currently circulating in Lebanon, and these serotypes are as follows: 1, 4, 6, 8, 16 and 24. This study is the first report that confirms the presence and circulation of BTV in Lebanon. © 2013 Blackwell Verlag GmbH.
Engineering Venom’s Toxin-Neutralizing Antibody Fragments and Its Therapeutic Potential
Alvarenga, Larissa M.; Zahid, Muhammad; di Tommaso, Anne; Juste, Matthieu O.; Aubrey, Nicolas; Billiald, Philippe; Muzard, Julien
2014-01-01
Serum therapy remains the only specific treatment against envenoming, but anti-venoms are still prepared by fragmentation of polyclonal antibodies isolated from hyper-immunized horse serum. Most of these anti-venoms are considered to be efficient, but their production is tedious, and their use may be associated with adverse effects. Recombinant antibodies and smaller functional units are now emerging as credible alternatives and constitute a source of still unexploited biomolecules capable of neutralizing venoms. This review will be a walk through the technologies that have recently been applied leading to novel antibody formats with better properties in terms of homogeneity, specific activity and possible safety. PMID:25153256
Kang, Changkeun; Han, Dae-Yong; Park, Kwang-Il; Pyo, Min-Jung; Heo, Yunwi; Lee, Hyunkyoung; Kim, Gon Sup; Kim, Euikyung
2014-08-01
Jellyfish stings have often caused serious health concerns for sea bathers especially in tropical waters. In the coastal areas of Korea, China and Japan, the blooming and stinging accidents of poisonous jellyfish species have recently increased, including Nemopilema nomurai. We have generated a polyclonal antibody against N. nomurai jellyfish venom (NnV) by the immunization of white rabbits with NnV antigen. In the present study, the antibody has been characterized for its neutralizing effect against NnV. At first, the presence of NnV polyclonal antibody has been confirmed from the immunized rabbit serum by Enzyme linked immunosorbent assay (ELISA). Then, the neutralizing activities of the polyclonal antibody have been investigated using cell-based toxicity test, hemolysis assay, and mice lethality test. When the polyclonal antibody was preincubated with NnV, it shows a high effectiveness in neutralizing the NnV toxicities in a concentration-dependent manner. Moreover, we explored proteomic analyses using 2-D SDS-PAGE and MALDI-TOF mass spectrometry to illustrate the molecular identities of the jellyfish venom. From this, 18 different protein families have been identified as jellyfish venom-derived proteins; the main findings of which are matrix metalloproteinase-14, astacin-like metalloprotease toxin 3 precursor. It is expected that the present results would have contributed to our understandings of the envenomation by N. nomurai, their treatment and some valuable knowledge on the pathological processes of the jellyfish stinging. Copyright © 2014 Elsevier Ltd. All rights reserved.
Sotelo, Elena; Llorente, Francisco; Rebollo, Belen; Camuñas, Ana; Venteo, Angel; Gallardo, Carmina; Lubisi, Alison; Rodríguez, María José; Sanz, Antonio J; Figuerola, Jordi; Jiménez-Clavero, Miguel Ángel
2011-06-01
West Nile virus (WNV) is an emerging zoonotic pathogen with a wide range of hosts, including birds, horses and humans. The development and evaluation of the performance of a new enzyme-linked immunosorbent assay (ELISA) are described for rapid detection of WNV-specific antibodies in samples originating from an extensive range of vertebrates susceptible to WNV infection. The assay uses a monoclonal antibody (MAb) which binds whole virus particles and neutralizes infection in vitro by recognizing a neutralizing epitope within the envelope (E) glycoprotein of the virus. This MAb, labelled with horseradish peroxidase, was used to compete with WNV-specific serum antibodies for virus-binding in vitro. The epitope-blocking ELISA was optimized in a manner that enabled its validation with a number of experimental and field sera, from a wide range of wild bird species, and susceptible mammals. The new ELISA exhibited high specificity (79.5-96.5%) and sensitivity (100%), using the virus-neutralization test as reference standard. It also required a much lower volume of sample (10 μl per analysis) compared to other ELISAs available commercially. This new method may be helpful for diagnosis and disease surveillance, particularly when testing samples from small birds, which are available in limited amounts. Copyright © 2011 Elsevier B.V. All rights reserved.
Dill, Veronika; Hoffmann, Bernd; Zimmer, Aline; Beer, Martin; Eschbaumer, Michael
2018-03-16
Suspension culture of BHK cells allows large-scale virus propagation and cost-efficient vaccine production, while the shift to animal-component-free cell culture media without serum is beneficial for the quality and downstream processing of the product. Foot-and-mouth disease virus is still endemic in many parts of the world and high-quality vaccines are essential for the eradication of this highly contagious and economically devastating disease. Changes to the viral genome sequence during passaging in an adherent and a suspension cell culture system were compared and the impact of amino acid substitutions on receptor tropism, antigenicity and particle stability was examined. Virus production in suspension cells in animal-component-free media and in serum-containing media as well as in adherent cells in serum-containing media was compared. Infection kinetics were determined and the yield of intact viral particles was estimated in all systems using sucrose density gradient centrifugation. Capsid protein sequence alterations were serotype-specific, but varied between cell lines. But The A 24 -2P virus variant had expanded its receptor tropism, but virus neutralization tests found no changes in the antigenic profile in comparison to the original viruses. There were no differences in viral titer between a suspension and an adherent cell culture system, independent of the type of media used. Also, the usage of a serum-free suspension culture system promoted viral growth and allowed an earlier harvest. For serotype O isolates, no differences were seen in the yield of 146S particles. Serotype A preparations revealed a decreased yield of 146S particles in suspension cells independent of the culture media. The selective pressure of the available surface receptors in different cell culture systems may be responsible for alterations in the capsid coding sequence of culture-grown virus. Important vaccine potency characteristics such as viral titer and the neutralization profile were unaffected, but the 146S particle yield differed for one of the tested serotypes.
Seroprevalences of Specific IgG Antibodies to Measles, Mumps, and Rubella in Korean Infants.
Cho, Hye Kyung; Lee, Hyunju; Kim, Han Wool; Kim, Sung Soon; Kang, Hae Ji; Kim, In Tae; Kim, Kyung Hyo
2016-12-01
In this study, the seroprevalences of measles, mumps, and rubella antibodies in infants were determined to assess the immunization strategy and control measures for these infectious diseases. Serum samples from infants < 1 year of age and their mothers were collected to measure the concentrations of specific IgG antibodies to measles, mumps, and rubella by enzyme-linked immunosorbent assay. For selected infant serum samples, measles-specific neutralizing antibody levels were determined by using the plaque reduction neutralization test. The sera from 295 of infants and 80 of their mothers were analyzed. No infants had past measles, mumps, or rubella infections. Almost all infants < 2 months of age were positive for measles and rubella IgG antibodies. However, seroprevalence of measles and rubella antibodies decreased with age, and measles IgG and rubella IgG were barely detectable after 4 months of age. The seroprevalence of mumps antibodies was lower than that of measles and rubella antibodies in infants ≤ 4 months old, and mumps IgG was barely detectable after 2 months of age. The seropositivity of measles-specific neutralizing antibody was 63.6% in infants aged 2 months and undetectable in infants ≥ 6 months old. Because the seropositivity rates of measles, mumps, and rubella antibodies were low after the first few months of age in Korean infants, active immunization with vaccines is strongly recommended for infants aged 6-11 months when measles is epidemic. Timely administration of the first dose of measles-mumps-rubella vaccine at 12 months of age should be encouraged in non-epidemic situations.
ViroSpot microneutralization assay for antigenic characterization of human influenza viruses.
van Baalen, Carel A; Jeeninga, Rienk E; Penders, Germaine H W M; van Gent, Brenda; van Beek, Ruud; Koopmans, Marion P G; Rimmelzwaan, Guus F
2017-01-03
The hemagglutination inhibition (HI) assay has been used for the antigenic characterization of influenza viruses for decades. However, the majority of recent seasonal influenza A viruses of the H3N2 subtype has lost the capacity to agglutinate erythrocytes of various species. The hemagglutination (HA) activity of other A(H3N2) strains is generally sensitive to the action of the neuraminidase inhibitor oseltamivir, which indicates that the neuraminidase and not the hemagglutinin is responsible for the HA activity. These findings complicate the antigenic characterization and selection of A(H3N2) vaccine strains, calling for alternative antigenic characterization assays. Here we describe the development and use of the ViroSpot microneutralization (MN) assay as a reliable and robust alternative for the HI assay. Serum neutralization of influenza A(H3N2) reference virus strains and epidemic isolates was determined by automated readout of immunostained cell monolayers, in a format designed to minimize the influence of infectious virus doses on serum neutralization titers. Neutralization of infection was largely independent from rates of viral replication and cell-to-cell transmission, facilitating the comparison of different virus isolates. Other advantages of the ViroSpot MN assay include its relative insensitivity to variation in test dose of infectious virus, automated capture and analyses of residual infection patterns, and compatibility with standardized large scale analyses. Using this assay, a number of epidemic influenza A(H3N2) strains that failed to agglutinate erythrocytes, were readily characterized antigenically. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Seroprevalences of Specific IgG Antibodies to Measles, Mumps, and Rubella in Korean Infants
2016-01-01
In this study, the seroprevalences of measles, mumps, and rubella antibodies in infants were determined to assess the immunization strategy and control measures for these infectious diseases. Serum samples from infants < 1 year of age and their mothers were collected to measure the concentrations of specific IgG antibodies to measles, mumps, and rubella by enzyme-linked immunosorbent assay. For selected infant serum samples, measles-specific neutralizing antibody levels were determined by using the plaque reduction neutralization test. The sera from 295 of infants and 80 of their mothers were analyzed. No infants had past measles, mumps, or rubella infections. Almost all infants < 2 months of age were positive for measles and rubella IgG antibodies. However, seroprevalence of measles and rubella antibodies decreased with age, and measles IgG and rubella IgG were barely detectable after 4 months of age. The seroprevalence of mumps antibodies was lower than that of measles and rubella antibodies in infants ≤ 4 months old, and mumps IgG was barely detectable after 2 months of age. The seropositivity of measles-specific neutralizing antibody was 63.6% in infants aged 2 months and undetectable in infants ≥ 6 months old. Because the seropositivity rates of measles, mumps, and rubella antibodies were low after the first few months of age in Korean infants, active immunization with vaccines is strongly recommended for infants aged 6–11 months when measles is epidemic. Timely administration of the first dose of measles-mumps-rubella vaccine at 12 months of age should be encouraged in non-epidemic situations. PMID:27822935
Rota, Jennifer S.; Hickman, Carole J.; Mercader, Sara; Redd, Susan; McNall, Rebecca J.; Williams, Nobia; McGrew, Marcia; Walls, M. Laura; Rota, Paul A.; Bellini, William J.
2016-01-01
In the United States, approximately 9% of the measles cases reported from 2012 to 2014 occurred in vaccinated individuals. Laboratory confirmation of measles in vaccinated individuals is challenging since IgM assays can give inconclusive results. Although a positive reverse transcription (RT)-PCR assay result from an appropriately timed specimen can provide confirmation, negative results may not rule out a highly suspicious case. Detection of high-avidity measles IgG in serum samples provides laboratory evidence of a past immunologic response to measles from natural infection or immunization. High concentrations of measles neutralizing antibody have been observed by plaque reduction neutralization (PRN) assays among confirmed measles cases with high-avidity IgG, referred to here as reinfection cases (RICs). In this study, we evaluated the utility of measuring levels of measles neutralizing antibody to distinguish RICs from noncases by receiver operating characteristic curve analysis. Single and paired serum samples with high-avidity measles IgG from suspected measles cases submitted to the CDC for routine surveillance were used for the analysis. The RICs were confirmed by a 4-fold rise in PRN titer or by RT-quantitative PCR (RT-qPCR) assay, while the noncases were negative by both assays. Discrimination accuracy was high with serum samples collected ≥3 days after rash onset (area under the curve, 0.953; 95% confidence interval [CI], 0.854 to 0.993). Measles neutralizing antibody concentrations of ≥40,000 mIU/ml identified RICs with 90% sensitivity (95% CI, 74 to 98%) and 100% specificity (95% CI, 82 to 100%). Therefore, when serological or RT-qPCR results are unavailable or inconclusive, suspected measles cases with high-avidity measles IgG can be confirmed as RICs by measles neutralizing antibody concentrations of ≥40,000 mIU/ml. PMID:27335386
Ulloa, Armando; Langevin, Stanley A; Mendez-Sanchez, J D; Arredondo-Jimenez, Juan I; Raetz, Janae L; Powers, Ann M; Villarreal-Treviño, C; Gubler, Duane J; Komar, Nicholas
2003-01-01
A serologic survey in domestic animals (birds and mammals) was conducted in four communities located in the Lacandón Forest region of northeastern Chiapas, Mexico, during June 29 to July 1, 2001, with the objective to identify zoonotic arboviruses circulating in this area. We collected 202 serum samples from healthy domestic chickens, geese, ducks, turkeys, horses and cattle. The samples were tested by plaque-reduction neutralization test for antibodies to selected mosquito-borne flaviviruses (family Flaviviridae), including St. Louis encephalitis (SLE), Rocio (ROC), Ilheus (ILH), Bussuquara (BSQ), and West Nile (WN) viruses, and selected alphaviruses (family Togaviridae), including Western equine encephalitis (WEE), Eastern equine encephalomyelitis (EEE), and Venezuelan equine encephalitis (VEE) viruses. Neutralizing antibodies to SLE virus were detected in two (8%) of 26 turkeys, 15 (23%) of 66 cattle, and three (60%) of five horses. Antibodies to VEE virus were detected in 29 (45%) of 65 cattle. Because some of these animals were as young as 2 months old, we demonstrated recent activity of these two viruses. Sub-typing of the VEE antibody responses indicated that the etiologic agents of these infections belonged to the IE variety of VEE, which has been reported from other regions of Chiapas. WN virus-neutralizing antibodies were detected in a single cattle specimen (PRNT(90) = 1:80) that also circulated SLE virus-neutralizing antibodies (PRNT(90) = 1:20), suggesting that WN virus may have been introduced into the region. We also detected weak neutralizing activity to BSQ virus in four cattle and a chicken specimen, suggesting the presence of this or a closely related virus in Mexico. There was no evidence for transmission of the other viruses (ROC, ILH, EEE, WEE) in the study area.
Exposure of Piglets to Enteroviruses Investigated by an Immunoassay Based on the EV-G1 VP4 Peptide.
Benkahla, Mehdi A; Sane, Famara; Desailloud, Rachel; Hober, Didier
2016-01-01
The aim of this study was to investigate the exposure of piglets to enteroviruses-G (EV-G) through the presence of antibodies in their serum. Serum samples were obtained from the vena cava of 10 piglets at 9 weeks of age and again 39 days later (day 39). They were tested using an immunoassay based on the EV-G1 VP4 peptide, since VP4 is highly conserved among the four Enterovirus capsid proteins, and by using a seroneutralization assay. For each serum collected on day 39 the optical density was high compared to the value obtained in serum collected earlier (p = 0.002). However, the titers of anti-EV-G1 serum neutralizing activity were not different in paired samples (p > 0.999). The sequence alignment of the EV-G1 VP4 peptide, encompassing 50 amino acids, used in the immunoassay showed 88% homology with EV-G, suggesting that antibodies directed toward other EV-G than EV-G1 may be detected. An immunoassay based on EV-G1 VP4 can detect an increased level of EV-G antibodies in piglet serum samples. Further studies are needed to determine whether this immunoassay may be useful for diagnosis and/or epidemiological studies and to monitor EV-G infection in pigs to evaluate strategies aimed to prevent enterovirus infections. © 2016 S. Karger AG, Basel.
Curry, Patricia S; Ribble, Carl; Sears, William C; Hutchins, Wendy; Orsel, Karin; Godson, Dale; Lindsay, Robbin; Dibernardo, Antonia; Kutz, Susan J
2014-04-01
We compared Nobuto filter paper (FP) whole-blood samples to serum for detecting antibodies to seven pathogens in reindeer (Rangifer tarandus tarandus). Serum and FP samples were collected from captive reindeer in 2008-2009. Sample pairs (serum and FP eluates) were assayed in duplicate at diagnostic laboratories with the use of competitive enzyme-linked immunosorbent assays (cELISAs) for Neospora caninum and West Nile virus (WNV); indirect ELISA (iELISAs) for bovine herpesvirus type 1 (BHV-1), parainfluenza virus type 3 (PI-3), and bovine respiratory syncytial virus (BRSV); and virus neutralization (VN) for bovine viral diarrhea virus (BVDV) types I and II. Assay thresholds were evidence-based values employed by each laboratory. Comparable performance to serum was defined as FP sensitivity and specificity ≥ 80%. Filter-paper specificity estimates ranged from 92% in the cELISAs for N. caninum and WNV to 98% in the iELISAs for PI-3 and BRSV. Sensitivity was >85% for five tests (most ≥ 95%) but was insufficient (71-82%) for the PI-3 and BRSV iELISAs. Lowering the threshold for FP samples in these two ELISAs raised sensitivity to ≥ 87% and reduced specificity slightly (≥ 90% in three of the four test runs). Sample size limited the precision of some performance estimates. Based on the criteria of sensitivity and specificity ≥ 80%, and using adjusted FP thresholds for PI-3 and BRSV, FP sensitivity and specificity were comparable to serum in all seven assays. A potential limitation of FP is reduced sensitivity in tests that require undiluted serum (i.e., N. caninum cELISA and BVDV VNs). Possible toxicity to the assay cell layer in VN requires investigation. Results suggested that cELISA is superior to iELISA for detecting antibodies in FP samples from reindeer and other Rangifer tarandus subspecies. Our findings expand the potential utility of FP sampling from wildlife.
Trinh, Dai Quang; Ogawa, Haruko; Bui, Vuong Nghia; Nguyen, Tham Thi Hong; Gronsang, Dulyatad; Baatartsogt, Tugsbaatar; Kizito, Mugimba Kahoza; AboElkhair, Mohammed; Yamaguchi, Shigeo; Nguyen, Viet Khong; Imai, Kunitoshi
2015-09-01
A blocking latex agglutination test (b-LAT) developed in this study was evaluated for the detection of antibodies against chicken anemia virus (CAV) in chickens. Polystyrene latex beads were coupled with a neutralizing monoclonal antibody (mAb) to CAV (mAb-beads). When mAb-beads were mixed with antigens prepared from the lysate of MDCC-MSB1 cells infected with CAV, agglutination occurred. A short pre-incubation of CAV antigens with CAV-specific antiserum inhibited the agglutination of mAb-beads. The test results were obtained within 5min. The specificity of b-LAT was evaluated using sera from specific pathogen-free chickens and sera containing antibodies to avian influenza virus, Newcastle disease virus, infectious bursal disease virus, and Marek's disease virus; nonspecific agglutination and cross-reactivity with antibodies to unrelated viruses were not observed. The examination of 94 serum samples collected from commercial breeder chickens of various ages (17-63 weeks) revealed good agreement (93.6%, Kappa value=0.82) between b-LAT and a virus neutralization test, known to be most sensitive and specific in the detection of antibodies to CAV. These results indicate that b-LAT, a simple and rapid test, is a useful and reliable tool in CAV serology. Copyright © 2015 Elsevier B.V. All rights reserved.
Law, Jessica; McCorkell, Robert; Muench, Greg; Wynne-Edwards, Katherine; Schaetzl, Hermann M.; Solis, Cristina; Nourozieh, Narges; Waeckerlin, Regula; Eschbaumer, Michael; Horsman, Shawn; Czub, Markus
2017-01-01
The objective of this study was to test the hypothesis that porcine circovirus type-2 (PCV2) vaccination is efficacious when administered in the first week of life. Three groups of pigs were vaccinated with Circumvent either early (at the end of week 1), late (at the end of week 4), or not at all. All 3 groups were later challenged intranasally with PCV2 (at the end of week 5). Two other groups were immunized with keyhole limpet hemocyanin (KLH) as a novel antigen at the end of either week 1 or week 4. Weight, PCV2 genome copy number in serum and saliva, anti-KLH antibody titer, and serum PCV2-neutralizing antibodies were measured weekly. Early PCV2 vaccination or KLH antigen exposure resulted in earlier humoral responses that were slower to develop than in older piglets, yet converged with the responses to later vaccination within 5 wk. Both groups of vaccinated piglets had periods of higher PCV2-neutralizing antibody titers and lower viral levels shortly after weaning and PCV2 challenge, thus supporting the recent labelling of 1 Canadian PCV2 vaccine for use in week 1 and suggesting that early PCV2 vaccination can reduce piglet handling without compromising vaccine efficacy. PMID:28154456
Taniuchi, Mami; Platts-Mills, James A; Begum, Sharmin; Uddin, Md Jashim; Sobuz, Shihab U; Liu, Jie; Kirkpatrick, Beth D; Colgate, E Ross; Carmolli, Marya P; Dickson, Dorothy M; Nayak, Uma; Haque, Rashidul; Petri, William A; Houpt, Eric R
2016-06-08
Oral polio vaccine (OPV) and rotavirus vaccine (RV) exhibit poorer performance in low-income settings compared to high-income settings. Prior studies have suggested an inhibitory effect of concurrent non-polio enterovirus (NPEV) infection, but the impact of other enteric infections has not been comprehensively evaluated. In urban Bangladesh, we tested stools for a broad range of enteric viruses, bacteria, parasites, and fungi by quantitative PCR from infants at weeks 6 and 10 of life, coincident with the first OPV and RV administration respectively, and examined the association between enteropathogen quantity and subsequent OPV serum neutralizing titers, serum rotavirus IgA, and rotavirus diarrhea. Campylobacter and enterovirus (EV) quantity at the time of administration of the first dose of OPV was associated with lower OPV1-2 serum neutralizing titers, while enterovirus quantity was also associated with diminished rotavirus IgA (-0.08 change in log titer per tenfold increase in quantity; P=0.037), failure to seroconvert (OR 0.78, 95% CI: 0.64-0.96; P=0.022), and breakthrough rotavirus diarrhea (OR 1.34, 95% CI: 1.05-1.71; P=0.020) after adjusting for potential confounders. These associations were not observed for Sabin strain poliovirus quantity. In this broad survey of enteropathogens and oral vaccine performance we find a particular association between EV carriage, particularly NPEV, and OPV immunogenicity and RV protection. Strategies to reduce EV infections may improve oral vaccine responses. ClinicalTrials.gov Identifier: NCT01375647. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Bowen, Richard A.; O'Shea, Thomas J.; Shankar, Vidya; Neubaum, Melissa A.; Neubaum, Daniel J.; Rupprecht, Charles E.
2013-01-01
We determined the presence of rabies-virus-neutralizing antibodies (RVNA) in serum of 721 insectivorous bats of seven species captured, sampled, and released in Colorado and New Mexico, United States in 2003-2005. A subsample of 160 bats was tested for rabies-virus RNA in saliva. We sampled little brown bats (Myotis lucifugus) at two maternity roosts in Larimer County, Colorado; big brown bats (Eptesicus fuscus) at three maternity roosts in Morgan County, Colorado; and big brown bats at five maternity roosts in Larimer County. We also sampled hoary bats (Lasiurus cinereus) and silver-haired bats (Lasionycteris noctivagans) captured while drinking or foraging over water in Bernalillo County, New Mexico and at various locations in Larimer County. Big brown bats, little brown bats, long-legged myotis (Myotis volans), long-eared myotis (Myotis evotis), and fringed myotis (Myotis thysanodes) were also sampled over water in Larimer County. All species except long-eared myotis included individuals with RVNA, with prevalences ranging from 7% in adult female silver-haired bats to 32% in adult female hoary bats. None of the bats had detectable rabies-virus RNA in oropharyngeal swabs, including 51 bats of 5 species that had RVNA in serum. Antibody-positive bats were present in nine of the 10 maternity colonies sampled. These data suggest that wild bats are commonly exposed to rabies virus and develop a humoral immune response suggesting some degree of viral replication, but many infections fail to progress to clinical disease.
Jagu, Subhashini; Karanam, Balusubramanyam; Wang, Joshua W.; Zayed, Hatem; Weghofer, Margit; Brendle, Sarah A.; Balogh, Karla K.; Tossi, Kerstin Pino; Roden, Richard B.S.; Christensen, Neil D.
2016-01-01
Vaccination with the minor capsid protein L2, notably the 17–36 neutralizing epitope, induces broadly protective antibodies, although the neutralizing titers attained in serum are substantially lower than for the licensed L1 VLP vaccines. Here we examine the impact of other less reactogenic adjuvants upon the induction of durable neutralizing serum antibody responses and protective immunity after vaccination with HPV16 and HPV31 L2 amino acids 17–36 inserted at positions 587 and 453 of VP3, respectively, for surface display on Adeno-Associated Virus 2-like particles [AAVLP (HPV16/31L2)]. Mice were vaccinated three times subcutaneously with AAVLP (HPV16/31L2) at two week intervals at several doses either alone or formulated with alum, alum and MPL, RIBI adjuvant or Cervarix. The use of adjuvant with AAVLP (HPV16/31L2) was necessary in mice for the induction of L2-specific neutralizing antibody and protection against vaginal challenge with HPV16. While use of alum was sufficient to elicit durable protection (>3 months after the final immunization), antibody titers were increased by addition of MPL and RIBI adjuvants. To determine the breadth of immunity, rabbits were immunized three times with AAVLP (HPV16/31L2) either alone, formulated with alum ± MPL, or RIBI adjuvants, and after serum collection, the animals were concurrently challenged with HPV16/31/35/39/45/58/59 quasivirions or cottontail rabbit papillomavirus (CRPV) at 6 or 12 months post-immunization. Strong protection against all HPV types was observed at both 6 and 12 months post-immunization, including robust protection in rabbits receiving the vaccine without adjuvant. In summary, vaccination with AAVLP presenting HPV L2 17–36 epitopes at two sites on their surface induced cross-neutralizing serum antibody, immunity against HPV16 in the genital tract, and long-term protection against skin challenge with the 7 most common oncogenic HPV types when using a clinically relevant adjuvant. PMID:26382603
Lyssavirus Surveillance in Bats, Bangladesh
Niezgoda, Michael; Carroll, Darin S.; Keeler, Natalie; Hossain, Mohammed Jahangir; Breiman, Robert F.; Ksiazek, Thomas G.; Rupprecht, Charles E.
2006-01-01
Lyssavirus surveillance in bats was performed in Bangladesh during 2003 and 2004. No virus isolates were obtained. Three serum samples (all from Pteropus giganteus, n = 127) of 288 total serum samples, obtained from bats in 9 different taxa, neutralized lyssaviruses Aravan and Khujand. The infection occurs in bats in Bangladesh, but virus prevalence appears low. PMID:16704789
Atanasiu, P.; Cannon, D. A.; Dean, D. J.; Fox, J. P.; Habel, K.; Kaplan, M. M.; Kissling, R. E.; Koprowski, H.; Lépine, P.; Gallardo, F. Pérez
1961-01-01
This study is the third in a series on virus-neutralizing antibody response to different schedules of antirabies serum and vaccines in previously non-exposed persons. Three types of vaccine were studied—phenolized (Semple), duck embryo and high-egg-passage (HEP) chicken embryo. Reduced schedules of vaccine, consisting of 2-7 inoculations given at various intervals, did not give results comparable in efficacy (time of appearance, level and persistence of antibody) with schedules comprising at least 14 daily inoculations of vaccine as determined in previous trials. The effectiveness of a booster dose in previously sensitized individuals was confirmed with a demonstration that a rise in serum antibody appears between 4 and 8 days after the booster inoculation. Effective sensitization appears to be as much a function of spacing of inoculations as of total dosage of vaccine antigen. Interference by immune serum with the antigenicity of subsequently administered vaccine, noted previously by the present authors and by other workers, was again confirmed. This interference could be overcome by the administration of a sufficient amount of vaccine. PMID:13863061
Cross-Neutralization between Human and African Bat Mumps Viruses.
Katoh, Hiroshi; Kubota, Toru; Ihara, Toshiaki; Maeda, Ken; Takeda, Makoto; Kidokoro, Minoru
2016-04-01
Recently, a new paramyxovirus closely related to human mumps virus (MuV) was detected in bats. We generated recombinant MuVs carrying either or both of the fusion and hemagglutinin-neuraminidase bat virus glycoproteins. These viruses showed replication kinetics similar to human MuV in cultured cells and were neutralized efficiently by serum from healthy humans.
Ruwona, Tinashe B.; Giang, Erick; Nieusma, Travis
2014-01-01
ABSTRACT The hepatitis C virus (HCV) envelope glycoprotein E1E2 complex is a candidate vaccine antigen. Previous immunization studies of E1E2 have yielded various results on its ability to induce virus-neutralizing antibodies in animal models and humans. The murine model has become a vital tool for HCV research owing to the development of humanized mice susceptible to HCV infection. In this study, we investigated the antibody responses of mice immunized with E1E2 and a novel soluble form of E1E2 (sE1E2) by a DNA prime and protein boost strategy. The results showed that sE1E2 elicited higher antibody titers and a greater breadth of reactivity than the wild-type cell-associated E1E2. However, immune sera elicited by either immunogen were only weakly neutralizing. In order to understand the contrasting results of binding and serum neutralizing activities, epitopes targeted by the polyclonal antibody responses were mapped and monoclonal antibodies (MAbs) were generated. The results showed that the majority of serum antibodies were directed to the E1 region 211 to 250 and the E2 regions 421 to 469, 512 to 539, 568 to 609, and 638 to 651, instead of the well-known immunodominant E2 hypervariable region 1 (HVR1). Unexpectedly, in MAb analysis, ∼12% of MAbs isolated were specific to the conserved E2 antigenic site 412 to 423, and 85% of them cross-neutralized multiple HCV isolates. The epitopes recognized by these MAbs are similar but distinct from the previously reported HCV1 and AP33 broadly neutralizing epitopes. In conclusion, E1E2 can prime B cells specific to conserved neutralizing epitopes, but the levels of serum neutralizing antibodies elicited are insufficient for effective virus neutralization. The sE1E2 constructs described in this study can be a useful template for rational antigen engineering. IMPORTANCE Hepatitis C virus infects 2 to 3% of the world's population and is a leading cause of liver failures and the need for liver transplantation. The virus envelope glycoprotein complex E1E2 produced by detergent extraction of cells overexpressing the protein was evaluated in a phase I clinical trial but failed to induce neutralizing antibodies in most subjects. In this study, we designed a novel form of E1E2 which is secreted from cells and is soluble and compared it to wild-type E1E2 by DNA immunization of mice. The results showed that this new E1E2 is more immunogenic than wild-type E1E2. Detailed mapping of the antibody responses revealed that antibodies to the conserved E2 antigenic site 412 to 423 were elicited but the serum concentrations were too low to neutralize the virus effectively. This soluble E1E2 provides a new reagent for studying HCV and for rational vaccine design. PMID:24965471
Oliveira-Mendes, Bárbara Bruna Ribeiro; do Carmo, Anderson Oliveira; Duarte, Clara Guerra; Felicori, Liza Figueiredo; Machado-de-Ávila, Ricardo Andrez; Chávez-Olórtegui, Carlos; Kalapothakis, Evanguedes
2014-01-01
Background Scorpionism is a public health problem in Brazil, and Tityus serrulatus (Ts) is primarily responsible for severe accidents. The main toxic components of Ts venom are low-molecular-weight neurotoxins; however, the venom also contains poorly characterized high-molecular-weight enzymes. Hyaluronidase is one such enzyme that has been poorly characterized. Methods and principal findings We examined clones from a cDNA library of the Ts venom gland and described two novel isoforms of hyaluronidase, TsHyal-1 and TsHyal-2. The isoforms are 83% identical, and alignment of their predicted amino acid sequences with other hyaluronidases showed conserved residues between evolutionarily distant organisms. We performed gel filtration followed by reversed-phase chromatography to purify native hyaluronidase from Ts venom. Purified native Ts hyaluronidase was used to produce anti-hyaluronidase serum in rabbits. As little as 0.94 µl of anti-hyaluronidase serum neutralized 1 LD50 (13.2 µg) of Ts venom hyaluronidase activity in vitro. In vivo neutralization assays showed that 121.6 µl of anti-hyaluronidase serum inhibited mouse death 100%, whereas 60.8 µl and 15.2 µl of serum delayed mouse death. Inhibition of death was also achieved by using the hyaluronidase pharmacological inhibitor aristolochic acid. Addition of native Ts hyaluronidase (0.418 µg) to pre-neutralized Ts venom (13.2 µg venom+0.94 µl anti-hyaluronidase serum) reversed mouse survival. We used the SPOT method to map TsHyal-1 and TsHyal-2 epitopes. More peptides were recognized by anti-hyaluronidase serum in TsHyal-1 than in TsHyal-2. Epitopes common to both isoforms included active site residues. Conclusions Hyaluronidase inhibition and immunoneutralization reduced the toxic effects of Ts venom. Our results have implications in scorpionism therapy and challenge the notion that only neurotoxins are important to the envenoming process. PMID:24551256
[Antibodies to various phospholipids in SLE patients with primary antiphospholipid syndrome].
Reshetniak, T M; Boĭtsekhovskaia, B; Alekberova, Z S; Kalashnikova, L A; Mach, E S; Zabek, Ia
1999-01-01
Antiphospholipid antibodies (aPL) represent a heterogeneous population reacting with negatively charged, less frequently neutral phospholipids and/or phospholipid-binding serum proteins. The study was made of antibodies to a wide spectrum of phospholipids: to negatively charged phospholipids such as phosphatide acid (aPA), cardiolipin (aCL), phosphatidylcholine (aPS), phosphatidylinositol (aPI), phosphatidylglycerol (aPG) and to neutrally charged phospholipid--phosphatidylcholine (aPC)--in 54 patients with systemic lupus erythematosus (SLE) and 29 patients with primary antiphospholipid syndrome (PAPS). The test for lupus anticoagulant (LAC) was also made. aPL in SLE patients free of antiphospholipid syndrome were detected in 61, 36 and 9% (aPC, aPS and aPA, aCL, respectively). aPI and aPG did not exceed normal values. 81% of SLE patients with antiphospholipid syndrome were LAC positive and 88% aPL positive. 60, 53, 44, 40, 13 and 17 were positive to aPC, aPA, aPS, aCL, aPG and aPI, respectively. Among patients with PAPS, the highest positivity was by LAC, occurrence of the other aPL was the same as in SLE patients with antiphospholipid syndrome. aCL, aPA, aPC, aPS, aPG and aPI were found in 55, 52, 41, 38, 31 and 21% of cases, respectively. In clinical manifestations of antiphospholipid syndrome and negative tests for LAC and aCL it is advisable to make tests for aPS and aPC. aPC occur in SLE patients more frequently than the other aPL: in 63% of SLE patients free of antiphospholipid syndrome and in 60% of SLE patients with this syndrome. Antibodies to other phospholipids, but not to cardiolipin, were present in SLE + APS in half of the cases but in SLE + PAPS in one third of the patients. Occurrence of aCL in the serum of SLE + PAPS patients is associated with the presence of antibodies to any other phospholipid irrespective of the charge. The severity of vascular changes did not correlate with the number of aPL variant found in the serum.
Seroka, D
1994-01-01
The aim of the study was to compare the antigen properties of a vaccine strain with street strains isolated from various animal hosts throughout the country. Investigation was carried out using monoclonal antibodies against NC protein. Also, two tests were carried out: the modified NIH test for potency and the neutralization test using the sera of people vaccinated against rabies (PM vaccine strain). The investigated street strains were used in both tests as the challenge viruses. A suspension of these strains diluted five times made it possible to avoid extreme values of animal survival (0% or 100%) what, consequently, made calculation of the LD50 value easier. A different rabies virus serotype (EBLI virus) in the population of insectivore bats Eptesicus serotinus and antigen variants within the first serotype, having common epitopes with strains of the vaccine virus SAD B19 and the polar rabies virus, were found to be present throughout the country. The concentrated and purified vaccine containing the PM virus did not protect mice against infection with strains of viruses isolated from bats (protection index 10 and lower). For the remaining strains, depending on the animal source of their isolation, the protection index ranged from 10 to 1000 and higher. The properties neutralizing a dose of 5 i.u./ml of serum from the subject inoculated with the vaccine containing the PM strain were similar for all the investigated strains; 0,5 i.u./ml did not neutralize the strain isolated from a racoon dog.
Wahome, Newton; Sully, Erin; Singer, Christopher; Thomas, Justin C; Hu, Lei; Joshi, Sangeeta B; Volkin, David B; Fang, Jianwen; Karanicolas, John; Jacobs, Donald J; Mantis, Nicholas J; Middaugh, C Russell
2016-05-01
RiVax is a candidate ricin toxin subunit vaccine antigen that has proven to be safe in human phase I clinical trials. In this study, we introduced double and triple cavity-filling point mutations into the RiVax antigen with the expectation that stability-enhancing modifications would have a beneficial effect on overall immunogenicity of the recombinant proteins. We demonstrate that 2 RiVax triple mutant derivatives, RB (V81L/C171L/V204I) and RC (V81I/C171L/V204I), when adsorbed to aluminum salts adjuvant and tested in a mouse prime-boost-boost regimen were 5- to 10-fold more effective than RiVax at eliciting toxin-neutralizing serum IgG antibody titers. Increased toxin neutralizing antibody values and seroconversion rates were evident at different antigen dosages and within 7 days after the first booster. Quantitative stability/flexibility relationships analysis revealed that the RB and RC mutations affect rigidification of regions spanning residues 98-103, which constitutes a known immunodominant neutralizing B-cell epitope. A more detailed understanding of the immunogenic nature of RB and RC may provide insight into the fundamental relationship between local protein stability and antibody reactivity. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.
Emmenegger, E.; Landolt, M.; LaPatra, S.; Winton, J.
1997-01-01
Three peptides, P76, P226, and P268 representing 3 putative antigen~c determinants on the glycoprotein of infectious hematopoietic necrosis virus (IHNV), were synthesized and injected into rainbow trout Oncorhynchus mykiss to assess their immunogen~city. Antisera extracted from the immunized trout were analyzed uslng an enzyme linked imrnunosorbent assay (ELISA) for the presence of antibodies that could bind to the peptides or to intact virions of IHNV. The antisera were also tested for neutralizing activity against IHNV by a complement-mediated neutralization assay. In general, recognition of the peptides and IHNV was low and only a few antibody binding patterns were demonstrated. Antisera from fish injected with P76 constructs recognized the homologous peptide more than the heterologous peptides, whereas antisera from fish inoculated with either P226 or P268 constructs recognized P76 equally, or better, than the homologous peptide; however, there was a high degree of individual variation within each treatment group. Neutralization actlvlty was demonstrated by serum from a single flsh lnlected with one of the pept~des (P268) and from 7 of 10 positive control f~sh Infected with an attenuated strain of IHNV Possible explanations for the dichotomous immune responses are discussed. These results indicate we need to improve our overall understanding of the
Broad and potent HIV-1 neutralization by a human antibody that binds the gp41-gp120 interface
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, Jinghe; Kang, Byong H.; Pancera, Marie
The isolation of human monoclonal antibodies is providing important insights into the specificities that underlie broad neutralization of HIV-1 (reviewed in ref. 1). Here we report a broad and extremely potent HIV-specific monoclonal antibody, termed 35O22, which binds a novel HIV-1 envelope glycoprotein (Env) epitope. 35O22 neutralized 62% of 181 pseudoviruses with a half-maximum inhibitory concentration (IC 50) <50 μg ml -1. The median IC 50 of neutralized viruses was 0.033 μg ml -1, among the most potent thus far described. 35O22 did not bind monomeric forms of Env tested, but did bind the trimeric BG505 SOSIP.664. Mutagenesis and amore » reconstruction by negative-stain electron microscopy of the Fab in complex with trimer revealed that it bound to a conserved epitope, which stretched across gp120 and gp41. The specificity of 35O22 represents a novel site of vulnerability on HIV Env, which serum analysis indicates to be commonly elicited by natural infection. Binding to this new site of vulnerability may thus be an important complement to current monoclonal-antibody-based approaches to immunotherapies, prophylaxis and vaccine design.« less
González, Nuria; McKee, Krisha; Lynch, Rebecca M; Georgiev, Ivelin S; Jimenez, Laura; Grau, Eulalia; Yuste, Eloísa; Kwong, Peter D; Mascola, John R; Alcamí, José
2018-01-01
Only a small fraction of HIV-1-infected patients develop broadly neutralizing antibodies (bNAbs), a process generally associated to chronic antigen stimulation. It has been described that rare aviremic HIV-1-infected patients can generate bNAbs but this issue remains controversial. To address this matter we have assessed bNAb responses in a large cohort of long-term non-progressors (LTNPs) with low or undetectable viremia. Samples from the LTNP cohort of the Spanish AIDS Research Network (87 elite and 42 viremic controllers) and a control population of 176 viremic typical-progressors (TPs) were screened for bNAbs using Env-recombinant viruses. bNAb specificities were studied by ELISA using mutated gp120, neutralization assays with mutated viruses, and peptide competition. Epitope specificities were also elucidated from the serum pattern of neutralization against a panel of diverse HIV-1 isolates. Broadly neutralizing sera were found among 9.3% LTNPs, both elite (7%) and viremic controllers (14%). Within the broadly neutralizing sera, CD4 binding site antibodies were detected by ELISA in 4/12 LTNPs (33%), and 16/33 of TPs (48%). Anti-MPER antibodies were detected in 6/12 LTNPs (50%) and 14/33 TPs (42%) whereas glycan-dependent HIV-1 bNAbs were more frequent in LTNPs (11/12, 92%) as compared to TPs (12/33, 36%). A good concordance between standard serum mapping and neutralization-based mapping was observed. LTNPs, both viremic and elite controllers, showed broad humoral immune responses against HIV-1, including activity against many major epitopes involved in bNAbs-mediated protection.
Serotypic characterization of rotaviruses derived from asymptomatic human neonatal infections.
Hoshino, Y; Wyatt, R G; Flores, J; Midthun, K; Kapikian, A Z
1985-01-01
Nineteen rotavirus strains derived from asymptomatic neonates (seven from England, five from Australia, two from Venezuela, and five from Sweden) were successfully cultivated in primary African green monkey kidney cell cultures, serotyped by plaque reduction neutralization tests, subgrouped by indirect enzyme-linked immunosorbent assay, and electropherotyped by polyacrylamide gel electrophoresis. All 19 strains were shown to fall into one of the four known human serotypes; serotype 1 (all Venezuelan strains), serotype 2 (all Swedish strains), serotype 3 (all Australian strains), or serotype 4 (all English strains). Hyperimmune guinea pig serum raised against the Venezuelan strain (M37) neutralized not only serotype 1 (strain Wa) but also serotype 4 (strain St. Thomas no. 3) viruses to a similar degree. The English, Australian, and Venezuelan isolates were found to belong to subgroup 2, and the Swedish strains were subgroup 1 viruses. The potential importance of these rotaviruses obtained from neonates as possible vaccine candidates is discussed. Images PMID:2984247
Bradley, J. A.
1985-01-01
Infectious bovine rhinotracheitis virus was eradicated from a 150 cow beef herd at the Animal Diseases Research Institute, Lethbridge, Alberta. Tests used to accomplish this included standard and modified serum-virus neutralization tests and an enzymelinked immunosorbent assay. These results and those of preliminary pilot studies in the herd and in a nonvaccinated, infectious bovine rhinotracheitis-infected 450 cow beef herd suggest that eradication of infectious bovine rhinotracheitis infection can be considered as a practical control alternative to vaccination, and that young animals in purebred herds could be monitored serologically and isolated, to enhance their eligibility for entry into artificial insemination studs or for export. PMID:17422544
Yamazaki, Tatsuya; Nagashima, Maria; Ninomiya, Daisuke; Ainai, Akira; Fujimoto, Akira; Ichimonji, Isao; Takagi, Hidekazu; Morita, Naoko; Murotani, Kenta; Hasegawa, Hideki; Chiba, Joe; Akashi-Takamura, Sachiko
2018-01-01
The influenza virus causes annual epidemics and occasional pandemics and is thus a major public health problem. Development of vaccines and antiviral drugs is essential for controlling influenza virus infection. We previously demonstrated the use of vectored immune-prophylaxis against influenza virus infection. We generated a plasmid encoding neutralizing IgG monoclonal antibodies (mAbs) against A/PR/8/34 influenza virus (IAV) hemagglutinin (HA). We then performed electroporation of the plasmid encoding neutralizing mAbs (EP) in mice muscles and succeeded in inducing the expression of neutralizing antibodies in mouse serum. This therapy has a prophylactic effect against lethal IAV infection in mice. In this study, we established a new method of passive immunotherapy after IAV infection. We performed hydrodynamic injection of the plasmid encoding neutralizing mAbs (HD) involving rapid injection of a large volume of plasmid-DNA solution into mice via the tail vein. HD could induce neutralizing antibodies in the serum and in several mucosal tissues more rapidly than in EP. We also showed that a single HD completely protected the mice even after infection with a lethal dose of IAV. We also established other isotypes of anti-HA antibody (IgA, IgM, IgD, and IgE) and showed that like anti-HA IgG, anti-HA IgA was also effective at combating upper respiratory tract IAV infection. Passive immunotherapy with HD could thus provide a new therapeutic strategy targeting influenza virus infection. PMID:29416543
Kalaiyarasu, Semmannan; Mishra, Niranjan; Rajukumar, Katherukamem; Nema, Ram Kumar; Behera, Sthita Pragnya
2015-01-01
The aim of this study was to develop an indirect ELISA using the helicase domain of bovine viral diarrhoea virus (BVDV) NS3 protein instead of full-length NS3 protein for detection of BVDV and BDV antibodies in sheep and goats and its validation by comparing its sensitivity and specificity with virus neutralization test (VNT) as the reference test. The purified 50 kDa recombinant NS3 protein was used as the coating antigen in the ELISA. The optimal concentration of antigen was 320 ng/well at a serum dilution of 1:20 and the optimal positive cut-off optical density value was 0.40 based on test results of 418 VNT negative sheep and goat sera samples. When 569 serum samples from sheep (463) and goats (106) were tested, the ELISA showed a sensitivity of 91.71% and specificity of 94.59% with BVDV VNT. A good correlation (93.67%) was observed between the two tests. It showed a sensitivity of 85% and specificity of 86.6% with VNT in detecting BDV antibody positive or negative samples. This study demonstrates the efficacy of truncated recombinant NS3 antigen based ELISA for seroepidemiological study of pestivirus infection in sheep and goats.
Antitoxin activity of aqueous extract of Cyclea peltata root against Naja naja venom
Sivaraman, Thulasi; Sreedevi, N. S.; Meenatchisundaram, S.; Vadivelan, R.
2017-01-01
OBJECTIVES: Snakebites are a significant and severe global health problem. Till date, anti-snake venom serum is the only beneficial remedy existing on treating the snakebite victims. As antivenom was reported to induce early or late adverse reactions to human beings, snake venom neutralizing potential for Cyclea peltata root extract was tested for the present research by ex vivo and in vivo approaches on Naja naja toxin. MATERIALS AND METHODS: Ex vivo evaluation of venom toxicity and neutralization assays was carried out. The root extracts from C. peltata were used to evaluate the Ex vivo neutralization tests such as acetylcholinesterase, protease, direct hemolysis assay, phospholipase activity, and procoagulant activity. Gas chromatography-mass spectrometry (GC-MS) analysis from root extracts of C. peltata was done to investigate the bioactive compounds. RESULTS: The in vivo calculation of venom toxicity (LD50) of N. naja venom remained to be 0.301 μg. C. peltata root extracts were efficiently deactivated the venom lethality, and effective dose (ED50) remained to be 7.24 mg/3LD50 of N. naja venom. C. peltata root extract was found effective in counteracting all the lethal effects of venom. GC-MS analysis of the plant extract revealed the presence of antivenom compounds such as tetradecanoic and octadecadienoic acid which have neutralizing properties on N. naja venom. CONCLUSION: The result from the ex vivo and in vivo analysis indicates that C. peltata plant root extract possesses significant compounds such as tetradecanoic acid hexadecanoic acid, heptadecanoic acid, and octadecadienoic acid which can counteract the toxins present in N. naja. PMID:29326487
Antitoxin activity of aqueous extract of Cyclea peltata root against Naja naja venom.
Sivaraman, Thulasi; Sreedevi, N S; Meenatchisundaram, S; Vadivelan, R
2017-01-01
Snakebites are a significant and severe global health problem. Till date, anti-snake venom serum is the only beneficial remedy existing on treating the snakebite victims. As antivenom was reported to induce early or late adverse reactions to human beings, snake venom neutralizing potential for Cyclea peltata root extract was tested for the present research by ex vivo and in vivo approaches on Naja naja toxin. Ex vivo evaluation of venom toxicity and neutralization assays was carried out. The root extracts from C. peltata were used to evaluate the Ex vivo neutralization tests such as acetylcholinesterase, protease, direct hemolysis assay, phospholipase activity, and procoagulant activity. Gas chromatography-mass spectrometry (GC-MS) analysis from root extracts of C. peltata was done to investigate the bioactive compounds. The in vivo calculation of venom toxicity (LD 50 ) of N. naja venom remained to be 0.301 μg. C. peltata root extracts were efficiently deactivated the venom lethality, and effective dose (ED 50 ) remained to be 7.24 mg/3LD 50 of N. naja venom. C. peltata root extract was found effective in counteracting all the lethal effects of venom. GC-MS analysis of the plant extract revealed the presence of antivenom compounds such as tetradecanoic and octadecadienoic acid which have neutralizing properties on N. naja venom. The result from the ex vivo and in vivo analysis indicates that C. peltata plant root extract possesses significant compounds such as tetradecanoic acid hexadecanoic acid, heptadecanoic acid, and octadecadienoic acid which can counteract the toxins present in N. naja .
THE INDUCED SUSCEPTIBILITY OF THE GUINEA-PIG TO THE TOXIC ACTION OF THE BLOOD SERUM OF THE HORSE.
Lewis, P A
1908-01-01
Following the divisions before used, the results presented in the preceding pages may be briefly stated. I. The particular method of sensitization and the place where the test injection is made have an important bearing on the results obtained by various workers. Comparing the results obtained by the various methods, we may conclude that the incubation period of the hypersensitive reaction is not sharply limited, but that there is a progressive increase in sensitiveness from the sixth day, and presumably before that, extending over a period of several weeks. It seems very probable that the degree of hypersensitiveness attained where the sensitizing dose consists of a mixture of diphtheria toxin and serum is greater than when a single dose of the same small quantity of serum is given alone. II. Our early experiments, the first in this field, are in thorough agreement with those first reported by Otto, and shortly after him by Rosenau and Anderson. III. This hypersensitive reaction is transmissible from mother to offspring. The transmission is probably not equally effective in all cases, and individual young guinea-pigs probably vary greatly in the rate with which they lose their ability to react. As a result not all of the young of a hypersensitive mother react to a subcutaneous dose of five cubic centimeters of serum given when they are four or five weeks old. The reaction in the young animals differs quite markedly from that in those actively sensitized. These differences are such as to indicate that in the mother there is a considerable localization of the reaction in tissues and organs whose destruction does not cause sudden death. This local reaction is a protective factor and is not transmitted to the same degree as the factors involved in the fatal acute reaction. IV. The hypersensitive reaction to horse serum depends on the development of a special anti-body during the incubation period, which anti-body may be passively transferred to a fresh animal. If the dose of hypersensitive serum be sufficient, and the intoxicating injection be given directly into the circulation, this passive hypersensitiveness may be enough so that the animal will die when tested. There is also in the serum of hypersensitive guinea-pigs an uneliminated horse serum element or "rest," which is distinct from this antibody, and probably without influence on the course of the acute reaction. V. The anti-body on which the hypersensitive reaction depends may be entirely neutralized by horse serum without causing symptoms. The gradual introduction of increasing doses over a total period of twenty-four hours suffices for this. The animal is then, properly speaking, neither immune nor refractory, but is essentially in the condition of a normal animal which has recently had a large dose of horse serum. This rapid neutralization is made possible by the great binding power which the subcutaneous and other relatively unimportant tissues have for the toxic element of the serum. The so-called "Phenomenon of Arthus" is probably the same reaction for the rabbit that we have here dealt with in the guinea-pig. The fact that the manifestation is more prominently a local one depends on racial differences. I have encountered cases in the guinea-pig in which the conditions in the rabbit are closely simulated.
Analysis of ovine colostrum to detect antibody against progressive pneumonia virus.
Taylor, T B; Banowetz, G M; Schipper, I A; Gabrielson, D A
1982-01-01
Immunoglobulins were isolated and purified from the colostrum and serum of progressive pneumonia virus infected sheep and also from non-infected control sheep. Four classes of immunoglobulins were isolated from sheep colostrum (IgG1, IgG2, IgA and Ig10s). Three classes of immunoglobulins were isolated from sheep serum (IgG1, IgG2 and IgM). Low levels of virus neutralizing activity were demonstrated only in the whole serum and purified serum IgG1 preparations. No complement fixing activity was detected in any of the antibody preparations from colostrum. PMID:6284323
Kumar, Amit; Yogisharadhya, Revanaiah; Venkatesan, Gnanavel; Bhanuprakash, Veerakyathappa; Pandey, Awadh Bihari; Shivachandra, Sathish Bhadravati
2017-05-01
Buffalopox virus (BPXV) and other vaccinia-like viruses (VLVs) are causing an emerging/re-emerging zoonosis affecting buffaloes, cattle and humans in India and other countries. A27L and H3L are immuno-dominant major envelope proteins of intracellular mature virion (IMV) of orthopoxviruses (OPVs) and are highly conserved with an ability to elicit neutralizing antibodies. In the present study, two recombinant proteins namely; rA27L ( 21 S to E 110 ; ∼30 kDa) and rH3L( 1 M to I 280 ; ∼50 kDa) of BPXV-Vij/96 produced from Escherichia coli were used in vaccine formulation. A combined recombinant subunit vaccine comprising rA27L and rH3L antigens (10 μg of each) was used for active immunization of adult mice (20μg/dose/mice) with or without adjuvant (FCA/FIA) by intramuscular route. Immune responses revealed a gradual increase in antigen specific serum IgG as well as neutralizing antibody titers measured by using indirect-ELISA and serum neutralization test (SNT) respectively, which were higher as compared to that elicited by individual antigens. Suckling mice passively administered with combined anti-A27L and anti-H3L sera showed a complete (100%) pre-exposure protection upon challenge with virulent BPXV. Conclusively, this study highlights the potential utility of rA27L and rH3L proteins as safer candidate prophylactic antigens in combined recombinant subunit vaccine for buffalopox as well as passive protective efficacy of combined sera in employing better pre-exposure protection against virulent BPXV. Copyright © 2017 Elsevier B.V. All rights reserved.
Immunotherapy of acute radiation syndromes with antiradiation gamma G globulin.
NASA Astrophysics Data System (ADS)
Popov, Dmitri; Maliev, Vecheslav; Casey, Rachael; Jones, Jeffrey; Kedar, Prasad
Introduction: If an immunotherapy treatment approach to treatment of acute radiation syndromes (ARS) were to be developed; consideration could be given to neutralization of radiation toxins (Specific Radiation Determinants- SRD) by specific antiradiation antibodies. To accomplish this objective, irradiated animals were injected with a preparation of antiradiation immunoglobulin G (IgG) obtained from hyperimmune donors. Radiation-indeced toxins that we call Specific Radiation Determinants (SRD) possess toxic (neurotoxic, haemotoxic and enterotoxic) characteristics as well as specific antigenic properties that combined with the direct physiochemical direct radiation damage, induce the development of many of the pathological processes associated with ARS. We tested several specific hyperimmune IgG preparations against these radiation toxins and observed that their toxic properties were neutralized by specific antiradiation IgGs. Material and Methods: Rabbits were inoculated with SRD radiation toxins to induce hyperimmune serum. The hyperimmune serum was pooled from several animals, purified, and concentrated. Enzyme-linked immunosorbent assays of the hyperimmune serum revealed high titers of IgG with specific binding to radiation toxins. The antiradiation IgG preparation was injected into laboratory animals one hour before and three hours after irradiation, and was evaluated for its ability to protect inoculated animals against the development of acute radiation syndromes. Results: Animals that were inoculated with specific antiradiation antibodies before receiving lethal irradiation at LD 100/30 exhibited 60-75% survival rate at 30 days, whereas all control animals expired by 30 days following exposure. These inoculated animals also exhibited markedly reduced clinical symptoms of ARS, even those that did not survive irradiation. Discussion: The results of our experiments demonstrate that rabbit hyperimmune serum directed against SRD toxins afford significant, albeit incomplete, protection against high doses of radiation. In comparison, the mortality rate of irradiated control animals was 100% in the same time period. The mortality rates of hyperimmune serum-treated animals varied in different groups of animals and different forms of ARS; however, significant radioprotection was observed in each group treated with IgGs activated against specific radiation toxins.
Weiss, J; Elsbach, P; Shu, C; Castillo, J; Grinna, L; Horwitz, A; Theofan, G
1992-01-01
The bactericidal/permeability-increasing protein (BPI) of neutrophils and BPI fragments neutralize the effects of isolated Gram-negative bacterial lipopolysaccharides both in vitro and in vivo. Since endotoxin most commonly enters the host as constituents of invading Gram-negative bacteria, we raised the question: Can BPI and its bioactive fragments also protect against whole bacteria? To determine whether the bactericidal and endotoxin-neutralizing activities of BPI/fragments are expressed when Gram-negative bacteria are introduced to the complex environment of whole blood we examined the effects of added BPI and proteolytically prepared and recombinant NH2-terminal fragments on: (a) the fate of serum-resistant encapsulated Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa that survive the antibacterial actions of whole blood and (b) the ability of these bacteria to trigger cytokine release. Added BPI in nanomolar concentrations killed each of three encapsulated strains of E. coli and in closely parallel fashion inhibited tumor necrosis factor (TNF) release. Holo-BPI and its NH2-terminal fragment were equipotent toward a rough LPS chemotype K1-encapsulated strain, but the fragment was substantially more potent than holo-BPI toward two encapsulated smooth LPS chemotype strains. TNF release induced by K. pneumoniae and P. aeruginosa was also inhibited by both holo-BPI and fragment but, at the protein concentrations tested, P. aeruginosa was killed only by the fragment and K. pneumoniae was not killed by either protein. The bactericidal action of BPI/fragment toward E. coli is inhibited by C7-depleted serum, but accelerated by normal serum, indicating that BPI, acting in synergy with late complement components, enhances extracellular killing of serum-resistant bacteria. Thus, BPI and an even more potent NH2-terminal fragment may protect against Gram-negative bacteria in the host by blocking bacterial proliferation as well as endotoxin-mediated effects, not only as components of the intracellular antibacterial arsenal of the neutrophil, but also as potentially therapeutic extracellular agents. PMID:1522221
Weiss, J; Elsbach, P; Shu, C; Castillo, J; Grinna, L; Horwitz, A; Theofan, G
1992-09-01
The bactericidal/permeability-increasing protein (BPI) of neutrophils and BPI fragments neutralize the effects of isolated Gram-negative bacterial lipopolysaccharides both in vitro and in vivo. Since endotoxin most commonly enters the host as constituents of invading Gram-negative bacteria, we raised the question: Can BPI and its bioactive fragments also protect against whole bacteria? To determine whether the bactericidal and endotoxin-neutralizing activities of BPI/fragments are expressed when Gram-negative bacteria are introduced to the complex environment of whole blood we examined the effects of added BPI and proteolytically prepared and recombinant NH2-terminal fragments on: (a) the fate of serum-resistant encapsulated Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa that survive the antibacterial actions of whole blood and (b) the ability of these bacteria to trigger cytokine release. Added BPI in nanomolar concentrations killed each of three encapsulated strains of E. coli and in closely parallel fashion inhibited tumor necrosis factor (TNF) release. Holo-BPI and its NH2-terminal fragment were equipotent toward a rough LPS chemotype K1-encapsulated strain, but the fragment was substantially more potent than holo-BPI toward two encapsulated smooth LPS chemotype strains. TNF release induced by K. pneumoniae and P. aeruginosa was also inhibited by both holo-BPI and fragment but, at the protein concentrations tested, P. aeruginosa was killed only by the fragment and K. pneumoniae was not killed by either protein. The bactericidal action of BPI/fragment toward E. coli is inhibited by C7-depleted serum, but accelerated by normal serum, indicating that BPI, acting in synergy with late complement components, enhances extracellular killing of serum-resistant bacteria. Thus, BPI and an even more potent NH2-terminal fragment may protect against Gram-negative bacteria in the host by blocking bacterial proliferation as well as endotoxin-mediated effects, not only as components of the intracellular antibacterial arsenal of the neutrophil, but also as potentially therapeutic extracellular agents.
Lipidomics of human umbilical cord serum: identification of unique sterol sulfates.
Wood, Paul L; Siljander, Heli; Knip, Mikael
2017-08-01
There are currently limited lipidomics data for human umbilical cord blood. Therefore, the lipidomes of cord sera from six newborns and sera from six nonpregnant females were compared. Sera lipidomics analyses were conducted using a high-resolution mass spectrometry analytical platform. Cord serum contained a diverse array of glycerophospholipids, albeit generally at lower concentrations than monitored in adult serum. The unexpected observations were that cord serum contained several neurosteroid sulfates and bile acid sulfates that were not detectable in adult serum. Our data are the first to demonstrate that cord serum contains bile acid sulfates that are synthesized early in the hydroxylase, neutral and acidic pathways of primary bile acid biosynthesis and support previous publications of cord blood perfluoralkyl toxins in newborns.
CANINE DISTEMPER IN A VACCINATED SNOW LEOPARD ( PANTHERA UNCIA).
Chinnadurai, Sathya K; Kinsel, Michael J; Adkesson, Michael J; Terio, Karen
2017-12-01
A 6-yr-old male snow leopard ( Panthera uncia) presented with acute seizures, hyperthermia, and tachypnea. Because of a diagnosis of anuric renal failure, the animal was euthanized. On histopathologic examination, numerous intralesional intracytoplasmic and intranuclear inclusions were found in the lungs, lymph nodes, and stomach. Positive immunohistochemical staining for canine distemper virus (CDV) was found in the lungs and, to a lesser extent, in the lymph nodes and brain. Molecular testing yielded a CDV H gene sequence that was closely related to CDV isolates concurrently found in wild raccoons from adjacent forested areas. The leopard had been vaccinated once against CDV with the use of a recombinant canarypox-vectored live vaccine during a routine wellness examination 12 wk prior to death. Serial serum neutralization titers performed on banked serum collected between vaccination and death showed poor serologic response to the vaccine. This case demonstrates a probable failure of protection against naturally occurring CDV.
Julander, Justin G; Trent, Dennis W; Monath, Thomas P
2011-08-11
Live, attenuated yellow fever (YF) 17D vaccine is highly efficacious but causes rare, serious adverse events resulting from active replication in the host and direct viral injury to vital organs. We recently reported development of a potentially safer β-propiolactone-inactivated whole virion YF vaccine (XRX-001), which was highly immunogenic in mice, hamsters, monkeys, and humans [10,11]. To characterize the protective efficacy of neutralizing antibodies stimulated by the inactivated vaccine, graded doses of serum from hamsters immunized with inactivated XRX-001 or live 17D vaccine were transferred to hamsters by the intraperitoneal (IP) route 24h prior to virulent, viscerotropic YF virus challenge. Neutralizing antibody (PRNT(50)) titers were determined in the sera of treated animals 4h before challenge and 4 and 21 days after challenge. Neutralizing antibodies were shown to mediate protection. Animals having 50% plaque reduction neutralization test (PRNT(50)) titers of ≥40 4h before challenge were completely protected from disease as evidenced by viremia, liver enzyme elevation, and protection against illness (weight change) and death. Passive titers of 10-20 were partially protective. Immunization with the XRX-001 vaccine stimulated YF neutralizing antibodies that were equally effective (based on dose response) as antibodies stimulated by live 17D vaccine. The results will be useful in defining the level of seroprotection in clinical studies of new yellow fever vaccines. Copyright © 2011 Elsevier Ltd. All rights reserved.
Jurgilas, P B; Neves-Ferreira, A G; Domont, G B; Moussatché, H; Perales, J
1999-01-01
An antibothropic fraction (ABF) from Didelphis marsupialis (opossum) serum, which is responsible for the neutralization of Bothrops jararaca venom was isolated by Perales et al. [Perales, J., Moussatché, H., Marangoni, S., Oliveira, B. and Domont, G. B. (1994). Isolation and partial characterization of an antibothropic complex from the serum of South American Didelphidae. Toxicon 32, 1237-1249]. The aim of this work was to verify the presence of this factor in opossum's milk, which could represent an additional protection for the neonatal opossum against bothropic venoms. An active milk fraction was isolated and showed similar physicochemical, structural, antigenic and biological properties when compared to ABF, indicating that they are probably the same protein.
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.
Development of an Indirect ELISA for Serological Diagnosis of Bovine herpesvirus 5
Campos, Fabrício S.; da Rosa, Matheus C.; Finger, Paula F.; de Oliveira, Patricia D.; Conceição, Fabricio R.; Fischer, Geferson; Roehe, Paulo M.; Leite, Fábio P. L.
2016-01-01
Bovine herpesviruses 1 and 5 (BoHV-1 and BoHV-5) are economically important pathogens, associated with a variety of clinical syndromes, including respiratory and genital disease, reproductive failure and meningoencephalitis. The standard serological assay to diagnose BoHV-1 and BoHV-5 infections is the virus neutralization test (VNT), a time consuming procedure that requires manipulation of infectious virus. In the present study a highly sensitive and specific single dilution indirect ELISA was developed using recombinant glycoprotein D from BoHV-5 as antigen (rgD5ELISA). Bovine serum samples (n = 450) were screened by VNT against BoHV-5a and by rgD5ELISA. Compared with the VNT, the rgD5ELISA demonstrated accuracy of 99.8%, with 100% sensitivity, 96.7% specificity and coefficient of agreement between the tests of 0.954. The rgD5ELISA described here shows excellent agreement with the VNT and is shown to be a simple, convenient, specific and highly sensitive virus-free assay for detection of serum antibodies to BoHV-5. PMID:26866923
Borniger, Jeremy C; Walker Ii, William H; Surbhi; Emmer, Kathryn M; Zhang, Ning; Zalenski, Abigail A; Muscarella, Stevie L; Fitzgerald, Julie A; Smith, Alexandra N; Braam, Cornelius J; TinKai, Tial; Magalang, Ulysses J; Lustberg, Maryam B; Nelson, Randy J; DeVries, A Courtney
2018-05-14
We investigated relationships among immune, metabolic, and sleep abnormalities in mice with non-metastatic mammary cancer. Tumor-bearing mice displayed interleukin-6 (IL-6)-mediated peripheral inflammation, coincident with altered hepatic glucose processing and sleep. Tumor-bearing mice were hyperphagic, had reduced serum leptin concentrations, and enhanced sensitivity to exogenous ghrelin. We tested whether these phenotypes were driven by inflammation using neutralizing monoclonal antibodies against IL-6; despite the reduction in IL-6 signaling, metabolic and sleep abnormalities persisted. We next investigated neural populations coupling metabolism and sleep, and observed altered activity within lateral-hypothalamic hypocretin/orexin (HO) neurons. We used a dual HO-receptor antagonist to test whether increased HO signaling was causing metabolic abnormalities. This approach rescued metabolic abnormalities and enhanced sleep quality in tumor-bearing mice. Peripheral sympathetic denervation prevented tumor-induced increases in serum glucose. Our results link metabolic and sleep abnormalities via the HO system, and provide evidence that central neuromodulators contribute to tumor-induced changes in metabolism. Copyright © 2018 Elsevier Inc. All rights reserved.
Diagnostic gap in Bovine viral diarrhea virus serology during the periparturient period in cattle.
Bachofen, Claudia; Bollinger, Barbara; Peterhans, Ernst; Stalder, Hanspeter; Schweizer, Matthias
2013-09-01
Detection of antibodies against Bovine viral diarrhea virus (BVDV) in serum and milk by enzyme-linked immunosorbent assay (ELISA) is a crucial part of all ongoing national schemes to eradicate this important cattle pathogen. Serum and milk are regarded as equally suited for antibody measurement. However, when retesting a seropositive cow 1 day after calving, the serum was negative in 6 out of 9 different ELISAs. To further investigate this diagnostic gap around parturition, pre- and postcalving serum and milk samples of 5 cows were analyzed by BVDV antibody ELISA and serum neutralization test (SNT). By ELISA, 3 out of the 5 animals showed a diagnostic gap in the serum for up to 12 days around calving but all animals remained positive in SNT. In milk, the ELISA was strongly positive after birth but antibody levels decreased considerably within the next few days. Because of the immunoglobulin G (IgG)1-specific transport of serum antibodies into the mammary gland for colostrum production, the IgG subclass specificity of the total and the BVDV-specific antibodies were determined. Although all 5 animals showed a clear decrease in the total and BVDV-specific IgG1 antibody levels at parturition, the precalving IgG1-to-IgG2 ratios of the BVDV-specific antibodies were considerably lower in animals that showed the diagnostic gap. Results showed that BVDV seropositive cows may become "false" negative in several ELISAs in the periparturient period and suggest that the occurrence of this diagnostic gap is influenced by the BVDV-specific IgG subclass response of the individual animal.
Human antirabies gamma globulin*
Hosty, Thomas S.; Kissling, R. E.; Schaeffer, M.; Wallace, Gordon A.; Dibble, E. H.
1959-01-01
To obviate the foreign protein reactions experienced with the use of hyperimmune serum in rabies-exposed individuals, an attempt was made to produce a rabies antiserum of human origin. Five doses of an inactivated rabies virus duck-egg vaccine were administered to 34 volunteers at 4-day intervals (i.e., on days 0, 4, 8, 12 and 16). An additional dose of chick-embryo attenuated virus vaccine—Flury HEP (high egg passage)—was given on the 46th day, followed by a final booster dose of duck-egg vaccine on the 288th day. Twenty-four days later, i.e., on the 312th day after the first dose, the participants were bled and the serum pooled and converted to gamma globulin. These volunteers, having no initial antibody, responded with variable titres, the pooled serum having a titre of 1: 100 against 50 LD50 of rabies virus in neutralization tests and the gamma globulin prepared from this pool a titre of 1: 300. In five individuals inoculated with the antirabies gamma globulin, blood samples tested at intervals for residual antibody showed significant titres through 21 days. While the passive antibody levels resulting from the administration of a more potent immune horse serum were much higher than those achieved by the weaker human antirabies gamma globulin used, the decrease in titre was more gradual with the human globulin. With more booster inoculations in a larger group of human volunteers, it is believed that a human rabies immune gamma globulin could be produced which would be equal in effect to immune horse serum. The advantages of a human source of antibody in rabies prophylaxis are discussed. PMID:14403320
1984-05-01
YAHANOTO KAY 84 UNLSIID DM1-4C45 / /3 N EMhEEhEhEMEE I.’.’.MMMMN II.l I MI2 MICROCOPY RESOLUTION TEST CHART NATIONAL BUREAU OF STANDARDS 1963 A 1.0 w o...antigenic peptide sequences. Since antibodies against various parts (not limited to adsorption binding or its adjacent sites) of tail fiber contribute to...10 fold reduced rate of P2 neutralization.-This observation suggests that anti-P2 serum contains antibodies which cross-react with the G(-) products
Madej, Katarzyna; Persona, Karolina; Wandas, Monika; Gomółka, Ewa
2013-10-18
A complex extraction system with the use of cloud-point extraction technique (CPE) was developed for sequential isolation of basic and acidic/neutral medicaments from human plasma/serum, screened by HPLC/DAD method. Eight model drugs (paracetamol, promazine, chlorpromazine, amitriptyline, salicyclic acid, opipramol, alprazolam and carbamazepine) were chosen for the study of optimal CPE conditions. The CPE technique consists in partition of an aqueous sample with addition of a surfactant into two phases: micelle-rich phase with the isolated compounds and water phase containing a surfactant below the critical micellar concentration, mainly under influence of temperature change. The proposed extraction system consists of two chief steps: isolation of basic compounds (from pH 12) and then isolation of acidic/neutral compounds (from pH 6) using surfactant Triton X-114 as the extraction medium. Extraction recovery varied from 25.2 to 107.9% with intra-day and inter-day precision (RSD %) ranged 0.88-1087 and 5.32-17.96, respectively. The limits of detection for the studied medicaments at λ 254nm corresponded to therapeutic or low toxic plasma concentration levels. Usefulness of the proposed CPE-HPLC/DAD method for toxicological drug screening was tested via its application to analysis of two serum samples taken from patients suspected of drug overdosing. Published by Elsevier B.V.
Kansal, Rita; Davis, Catherine; Hansmann, Melanie; Seymour, Jon; Parsonnet, Jeffrey; Modern, Paul; Gilbert, Steve; Kotb, Malak
2007-05-01
Menstrual toxic shock syndrome (mTSS) is an acute febrile disease accompanied by hypotension and multiple organ involvement. Infection with Staphylococcus aureus producing the superantigen toxic shock syndrome toxin-1 (TSST-1) vaginally is necessary; however, only a small fraction of those infected with TSST-1 producing bacteria actually develop mTSS, suggesting that host factors modulate disease susceptibility. Serum antibodies to the toxin protect against development of the syndrome, but not all antibodies can neutralize the toxin. We set out to determine whether risk of developing the syndrome is related to the absence of neutralizing antibody and if antibody isotypes influence the neutralization capacity. In healthy subjects, TSST-1-binding serum antibodies were exclusively of the IgG and IgM classes; however, toxin-neutralizing capacity was correlated to the TSST-1-specific IgG1 and IgG4 antibodies (r (2)=0.88, p<0.0001 and 0.33, p<0.0086, respectively) but not with IgM antibodies. Specific IgA was not detectable. Compared to healthy matched controls who were colonized vaginally with S. aureus, IgG1 anti-TSST-1 antibodies and toxin neutralizing activity was lacking in all of the acute phases and in the majority of convalescent sera, suggesting that these patients may be incapable of generating TSST-1 neutralizing antibodies. These new findings support the hypothesis that host factors are important in the development of mTSS and that the anti-toxin isotype impacts antibody functionality.
Darvish, Maryam; Ebrahimi, Soltan Ahmad; Shahbazzadeh, Delavar; Bagheri, Kamran-Pooshang; Behdani, Mahdi; Shokrgozar, Mohammad Ali
2016-04-01
Scorpion envenoming is a serious health problem which can cause a variety of clinical toxic effects. Of the many scorpion species native to Iran, Hottentotta saulcyi is important because its venom can produce toxic effects in man. Nowadays, antivenom derived from hyper immune horses is the only effective treatment for sever scorpion stings. Current limitations of immunotherapy urgently require an efficient alternative with high safety, target affinity and more promising venom neutralizing capability. Recently, heavy chain-only antibodies (HC-Abs) found naturally in camelid serum met the above mentioned advantages. In this study, immuno-reactivities of polyclonal antibodies were tested after successful immunization of camel using H. saulcyi scorpion crude venom. The lethal potency of scorpion venom in C57BL/6 mice injected intraperitoneally was determined to be 2.7 mg/kg. These results were followed by the efficient neutralization of lethal activity of H. saulcyi scorpion venom by injection of antivenom and purified IgG fractions into mice intraperitonelly or intravenously, respectively. HC-Ab camelid antivenom could be considered as a useful serotherapeutics instead of present treatment for scorpion envenomation. Copyright © 2016. Published by Elsevier Ltd.
Franson, J. Christian; Hofmeister, Erik K.; Collins, Gail H.; Dusek, Robert J.
2011-01-01
We screened 1,397 feral horses (Equus caballus) on Sheldon National Wildlife Refuge, Nevada, United States, for IgM and IgG against flavivirus during 2004–2006, 2008, and 2009. Positive serum samples were tested for neutralizing antibodies to West Nile virus (WNV) and St. Louis encephalitis virus (SLEV). One animal was positive for antibody against WNV in 2004, but all others tested in 2004–2006 were negative. In 2008 and 2009, we found evidence of increasing seropositive horses with age, whereas seroprevalence of WNV decreased from 19% in 2008 to 7.2% in 2009. No horses were positive for antibody against SLEV. Being unvaccinated, feral horses can be useful for WNV surveillance.
Harmsen, T; Jongerius, M C; van der Zwan, C W; Plantinga, A D; Kraaijeveld, C A; Berbers, G A
1992-01-01
A 50% neutralization enzyme immunoassay (N50-EIA) was compared with an indirect enzyme-linked immunosorbent assay (ELISA) for determining mumps virus antibodies in three consecutive serum samples from 138 children vaccinated with a live mumps vaccine at the age (in years) of 1.5. By the N50-EIA, most (132 of 138) preserum samples did not show neutralizing activity. Eight to 12 weeks after vaccination, 17 of the children were still negative, but only 7 remained so after 2.5 years, resulting in a seroconversion rate of 125 of 132 (95%). Over the same period, the neutralization geometric mean titer rose from 3.6 to 9.9. By an indirect ELISA, 128 of 138 preserum samples were found negative. The early and late postvaccination sera of 8 children were ELISA negative, resulting in a seroconversion rate of 120 of 128 (94%). Only two children remained seronegative by both methods. Seven of the late postvaccination serum samples yielded noncorresponding results, reflecting 95% correlation between both methods. Due to cross-reactivity with parainfluenza viruses, the ELISA proved to be less specific, but on the other hand, it showed a greater sensitivity than the N50-EIA. PMID:1500523
Nasveld, Peter E; Marjason, Joanne; Bennett, Sonya; Aaskov, John; Elliott, Suzanne; McCarthy, Karen; Kanesa-Thasan, Niranjan; Feroldi, Emmanuel; Reid, Mark
2010-11-01
A randomized, double-blind, study was conducted to evaluate the safety, tolerability and immunogenicity of a live attenuated Japanese encephalitis chimeric virus vaccine (JE-CV) co-administered with live attenuated yellow fever vaccine (YF-17D strain; Stamaril®, Sanofi Pasteur) or administered successively. Participants (n = 108) were randomized to receive: YF followed by JE-CV 30 days later, JE followed by YF 30 days later, or the co-administration of JE and YF followed or preceded by placebo 30 days later or earlier. Placebo was used in a double-dummy fashion to ensure masking. Neutralizing antibody titers against JE-CV, YF-17D and selected wild-type JE strains was determined using a 50% serum-dilution plaque reduction neutralization test. Seroconversion was defined as the appearance of a neutralizing antibody titer above the assay cut-off post-immunization when not present pre-injection at day 0, or a least a four-fold rise in neutralizing antibody titer measured before the pre-injection day 0 and later post vaccination samples. There were no serious adverse events. Most adverse events (AEs) after JE vaccination were mild to moderate in intensity, and similar to those reported following YF vaccination. Seroconversion to JE-CV was 100% and 91% in the JE/YF and YF/JE sequential vaccination groups, respectively, compared with 96% in the co-administration group. All participants seroconverted to YF vaccine and retained neutralizing titers above the assay cut-off at month six. Neutralizing antibodies against JE vaccine were detected in 82-100% of participants at month six. These results suggest that both vaccines may be successfully co-administered simultaneously or 30 days apart.
Nasveld, Peter E; Marjason, Joanne; Bennett, Sonya; Aaskov, John; Elliott, Suzanne; McCarthy, Karen; Kanesa-thasan, Niranjan; Feroldi, Emmanuel
2010-01-01
A randomized, double-blind, study was conducted to evaluate the safety, tolerability and immunogenicity of a live attenuated Japanese encephalitis chimeric virus vaccine (JE-CV) co-administered with live attenuated yellow fever (YF) vaccine (YF-17D strain; Stamaril®, Sanofi Pasteur) or administered sequentially. Participants (n = 108) were randomized to receive: YF followed by JE-CV 30 days later, JE followed by YF 30 days later, or the co-administration of JE and YF followed or preceded by placebo 30 days later or earlier. Placebo was used in a double-dummy fashion to ensure masking. Neutralizing antibody titers against JE-CV, YF-17D and selected wild-type JE virus strains was determined using a 50% serum-dilution plaque reduction neutralization test (PRNT50). Seroconversion was defined as the appearance of a neutralizing antibody titer above the assay cut-off post-immunization when not present pre-injection at day 0, or a least a four-fold rise in neutralizing antibody titer measured before the pre-injection day 0 and later post vaccination samples. There were no serious adverse events. Most adverse events (AEs) after JE vaccination were mild to moderate in intensity, and similar to those reported following YF vaccination. Seroconversion to JE-CV was 100% and 91% in the JE/YF and YF/JE sequential vaccination groups, respectively, compared with 96% in the co-administration group. All participants seroconverted to YF vaccine and retained neutralizing titers above the assay cut-off at month six. Neutralizing antibodies against JE vaccine were detected in 82–100% of participants at month six. These results suggest that both vaccines may be successfully co-administered simultaneously or 30 days apart. PMID:20864814
Tiwari, Mugdha; Parida, Manmohan; Santhosh, S R; Khan, Mohsin; Dash, Paban Kumar; Rao, P V Lakshmana
2009-04-21
The recent resurgence of Chikungunya virus (CHIKV) in India and Indian Ocean Islands with unusual clinical severity is a matter of great public health concern. Despite the fact that CHIKV resurgence is associated with epidemic of unprecedented magnitude, no approved licensed vaccine is currently available. In the present study, a Vero cell adapted purified formalin inactivated prototype vaccine candidate was prepared using a current Indian strain implicated with the explosive epidemic during 2006. The bulk preparation of the vaccine candidate was undertaken in microcarrier based spinner culture using cytodex-1 in virus production serum free medium. The inactivation of the virus was accomplished through standard formalin inactivation protocol. The mice were immunized subcutaneously with alhydrogel gel formulation of inactivated virus preparation. The assessment of both humoral and cell-mediated immune response was accomplished through ELISA, plaque reduction neutralization test (PRNT), microcytotoxicity assay and cytokine production assay. The results revealed that formalin inactivated vaccine candidate induced both high titered ELISA (1:51,200) and plaque reduction neutralizing antibodies (1:6400) with peak antibody titer being observed during 6 -- 8 weeks of post-vaccination. In the absence of suitable murine challenge model, the protective efficacy was established by both in vitro and in vivo neutralization tests. Further assessment of cellular immunity through in vitro stimulation of spleenocytes from immunized mice revealed augmentation of high levels of both pro- and anti-inflammatory cytokines, indicating a mixed balance of Th1 and Th2 response. These findings suggest that the formalin inactivated Chikungunya vaccine candidate reported in this study has very good immunogenic potential to neutralize the virus infectivity by augmenting both humoral and cell-mediated immune response.
Chloride: the queen of electrolytes?
Berend, Kenrick; van Hulsteijn, Leonard Hendrik; Gans, Rijk O B
2012-04-01
Channelopathies, defined as diseases that are caused by mutations in genes encoding ion channels, are associated with a wide variety of symptoms and have been documented extensively over the past decade. In contrast, despite the important role of chloride in serum, textbooks in general do not allocate chapters exclusively on hypochloremia or hyperchloremia and information on chloride other than channelopathies is scattered in the literature. To systematically review the function of chloride in man, data for this review include searches of MEDLINE, PubMed, and references from relevant articles including the search terms "chloride," "HCl," "chloride channel" "acid-base," "acidosis," "alkalosis," "anion gap" "strong anion gap" "Stewart," "base excess" and "lactate." In addition, internal medicine, critical care, nephrology and gastroenterology textbooks were evaluated on topics pertaining the assessment and management of acid-base disorders, including reference lists from journals or textbooks. Chloride is, after sodium, the most abundant electrolyte in serum, with a key role in the regulation of body fluids, electrolyte balance, the preservation of electrical neutrality, acid-base status and it is an essential component for the assessment of many pathological conditions. When assessing serum electrolytes, abnormal chloride levels alone usually signify a more serious underlying metabolic disorder, such as metabolic acidosis or alkalosis. Chloride is an important component of diagnostic tests in a wide array of clinical situations. In these cases, chloride can be tested in sweat, serum, urine and feces. Abnormalities in chloride channel expression and function in many organs can cause a range of disorders. Copyright © 2011 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.
Huang, Zhen-Yu; Whitbeck, J. Charles; Ponce de Leon, Manuel; Lou, Huan; Wald, Anna; Krummenacher, Claude; Eisenberg, Roselyn J.; Cohen, Gary H.
2014-01-01
ABSTRACT Relatively little is known about the extent of the polyclonal antibody (PAb) repertoire elicited by herpes simplex virus (HSV) glycoproteins during natural infection and how these antibodies affect virus neutralization. Here, we examined IgGs from 10 HSV-seropositive individuals originally classified as high or low virus shedders. All PAbs neutralized virus to various extents. We determined which HSV entry glycoproteins these PAbs were directed against: glycoproteins gB, gD, and gC were recognized by all sera, but fewer sera reacted against gH/gL. We previously characterized multiple mouse monoclonal antibodies (MAbs) and mapped those with high neutralizing activity to the crystal structures of gD, gB, and gH/gL. We used a biosensor competition assay to determine whether there were corresponding human antibodies to those epitopes. All 10 samples had neutralizing IgGs to gD epitopes, but there were variations in which epitopes were seen in individual samples. Surprisingly, only three samples contained neutralizing IgGs to gB epitopes. To further dissect the nature of these IgGs, we developed a method to select out gD- and gB-specific IgGs from four representative sera via affinity chromatography, allowing us to determine the contribution of antibodies against each glycoprotein to the overall neutralization capacity of the serum. In two cases, gD and gB accounted for all of the neutralizing activity against HSV-2, with a modest amount of HSV-1 neutralization directed against gC. In the other two samples, the dominant response was to gD. IMPORTANCE Antibodies targeting functional epitopes on HSV entry glycoproteins mediate HSV neutralization. Virus-neutralizing epitopes have been defined and characterized using murine monoclonal antibodies. However, it is largely unknown whether these same epitopes are targeted by the humoral response to HSV infection in humans. We have shown that during natural infection, virus-neutralizing antibodies are principally directed against gD, gB, and, to a lesser extent, gC. While several key HSV-neutralizing epitopes within gD and gB are commonly targeted by human serum IgG, others fail to induce consistent responses. These data are particularly relevant to the design of future HSV vaccines. PMID:25142599
Martinón-Torres, Federico; Greenberg, David; Varman, Meera; Killar, John A; Hille, Darcy; Strable, Erica L; Stek, Jon E; Kaplan, Susan S
2017-04-01
Rotavirus is the leading cause of severe diarrhea in infants and young children. The current formulation of pentavalent rotavirus vaccine (RV5) must be stored refrigerated at 2-8°C. A modified formulation of RV5 (RV5mp) has been developed with stability at 37°C for 7 days and an expiry extended to 36 months when stored at 2-8°C. This study (ClinicalTrials.gov identifier: NCT01600092; EudraCT number: 2012-001611-23) evaluated the safety, tolerability and immunogenicity of RV5mp versus the currently marketed RV5 in infants. To maintain blinding, both vaccine formulations were stored refrigerated at 2-8°C for the duration of the study. Immunogenicity endpoints were (1) serum neutralizing antibody titers to human rotavirus serotypes G1, G2, G3, G4 and P1A[8] and (2) proportion of subjects with a ≥3-fold rise from baseline for serum neutralizing antibody to human rotavirus serotypes G1, G2, G3, G4 and P1A[8] and serum antirotavirus immunoglobulin A. The RV5mp group (n = 505) and RV5 group (n = 509) had comparable safety profiles. There were no deaths and no vaccine-related serious adverse events in this study. With respect to immunogenicity, RV5mp was noninferior compared with RV5. Serum neutralizing antibody responses by country and breast-feeding status were generally consistent with the overall results. RV5mp enhances storage requirements while maintaining the immunogenicity and safety profile of the currently licensed RV5. A vaccine that is stable at room temperature may be more convenient for vaccinators, particularly in places where the cold chain is unreliable, and ultimately will permit more widespread use.
Yamanaka, Atsushi; Konishi, Eiji
2017-09-25
Dengue is the most important arboviral disease worldwide. We previously reported that most inhabitants of dengue-endemic countries who are naturally immune to the disease have infection-enhancing antibodies whose in vitro activity does not decrease in the presence of complement (complement-independent enhancing antibodies, or CiEAb). Here, we compared levels of CiEAb and complement-dependent neutralizing antibodies (CdNAb) in dengue-immune humans. A typical antibody dose-response pattern obtained in our assay system to measure the balance between neutralizing and enhancing antibodies showed both neutralizing and enhancing activities depending on serum dilution factor. The addition of complement to the assay system increased the activity of neutralizing antibodies at lower dilutions, indicating the presence of CdNAb. In contrast, similar dose-response curves were obtained with and without complement at higher dilutions, indicating higher levels of CiEAb than CdNAb. For experimental support for the higher CiEAb levels, a cocktail of mouse monoclonal antibodies against dengue virus type 1 was prepared. The antibody dose-response curves obtained in this assay, with or without complement, were similar to those obtained with human serum samples when a high proportion of D1-V-3H12 (an antibody exhibiting only enhancing activity and thus a model for CiEAb) was used in the cocktail. This study revealed higher-level induction of CiEAb than CdNAb in humans naturally infected with dengue viruses.
Interleukin-23 mediates the pathogenesis of LPS/GalN-induced liver injury in mice.
Bao, Suxia; Zhao, Qiang; Zheng, Jianming; Li, Ning; Huang, Chong; Chen, Mingquan; Cheng, Qi; Zhu, Mengqi; Yu, Kangkang; Liu, Chenghai; Shi, Guangfeng
2017-05-01
Interleukin-23 (IL-23) is required for T helper 17 (Th17) cell responses and IL-17 production in hepatitis B virus infection. A previous study showed that the IL-23/IL-17 axis aggravates immune injury in patients with chronic hepatitis B virus infection. However, the role of IL-23 in acute liver injury remains unclear. The purpose of this study was to determine the role of the inflammatory cytokine IL-23 in lipopolysaccharide/d-galactosamine (LPS/GalN)-induced acute liver injury in mice. Serum IL-23 from patients with chronic hepatitis B virus (CHB), acute-on-chronic liver failure (ACLF) and healthy individuals who served as healthy controls (HCs) was measured by ELISA. An IL-23p19 neutralizing antibody or an IL-23p40 neutralizing antibody was administered intravenously at the time of challenge with LPS (10μg/kg) and GalN (400mg/kg) in C57BL/6 mice. Hepatic pathology and the expression of Th17-related cytokines, including IL-17 and TNF-α; neutrophil chemoattractants, including Cxcl1, Cxcl2, Cxcl9, and Cxcl10; and the stabilization factor Csf3 were assessed in liver tissue. Serum IL-23 was significantly upregulated in ACLF patients compared with CHB patients and HCs (P<0.05 for both). Serum IL-23 was significantly upregulated in the non-survival group compared with the survival group of ACLF patients, which was consistent with LPS/GalN-induced acute hepatic injury in mice (P<0.05 for both). Moreover, after treatment, serum IL-23 was downregulated in the survival group of ACLF patients (P<0.001). Compared with LPS/GalN mice, mice treated with either an IL-23p19 neutralizing antibody or an IL-23p40 neutralizing antibody showed less severe liver tissue histopathology and significant reductions in the expression of Th17-related inflammatory cytokine, including IL-17 and TNF-α; neutrophil chemoattractants, including Cxcl1, Cxcl2, Cxcl9, and Cxcl10; and stabilization factors Csf3 within the liver tissue compared with LPS/GalN mice (P<0.05 for all). High serum IL-23 was associated with mortality in ACLF patients and LPS/GalN-induced acute liver injury in mice. IL-23 neutralizing antibodies attenuated liver injury by reducing the expression of Th17-related inflammatory cytokines, neutrophil chemoattractants and stabilization factors within the liver tissue, which indicated that IL-23 likely functions upstream of Th17-related cytokine and chemokine expression to recruit inflammatory cells into the liver. Copyright © 2017 Elsevier B.V. All rights reserved.
Serological relatedness of herpes simplex viruses. Type-specificity of antibody response.
Skinner, G R; Thouless, M E; Trueman, S; Edwards, J; Gibbs, A J
1976-01-01
The serological relatedness of forty-seven strains of type 1 and type 2 herpes simplex virus was investigated by reciprocal and non-reciprocal neutralization kinetics. Early rabbit antisera divided the virus strains into two distinct groups where confident indentification of virus type was possible. Hyperimmune mouse and rabbit antisera did not divide the two virus types into two distinct non-over-lapping groups. The extent of overlap varied with the particular attribute of the virus being studied. The virus types were best discriminated by their neutralizability by type 1 antisera and least well by their neutralizability by type 2 antisera. The results of reciprocal kinetic neutralization test with hyperimmune mouse antisera were analysed by multi-dimensional cluster analysis. Hyperimmune mouse or rabbit antisera could not be discriminated with respect to their immunogenic type by their absolute neutralization rate constants against either type 1 or type 2 virus, but could be distinguished on a group basis by their relative neutralizability against both virus types (antiserum specificity attribute); however, using this latter criterion, the type of immunogen could only be predicted in seven of the forty antisera under test. 'Early' mouse antisera could also be distinguished as groups by their absolute k-values against type 1 herpes virus. Thus, immunogenic identification, on other than a group basis, was unreliable. The specificity of a given serum was inversely related to its titre. There was a positive correlation between the specificity of a given virus strain and of its corresponding antiserum. PMID:194831
Breaching peripheral tolerance promotes the production of HIV-1–neutralizing antibodies
Schroeder, Kristin M.S.; Harper, Michael S.; Santiago, Mario L.
2017-01-01
A subset of characterized HIV-1 broadly neutralizing antibodies (bnAbs) are polyreactive with additional specificities for self-antigens and it has been proposed immunological tolerance may present a barrier to their participation in protective humoral immunity. We address this hypothesis by immunizing autoimmune-prone mice with HIV-1 Envelope (Env) and characterizing the primary antibody response for HIV-1 neutralization. We find autoimmune mice generate neutralizing antibody responses to tier 2 HIV-1 strains with alum treatment alone in the absence of Env. Importantly, experimentally breaching immunological tolerance in wild-type mice also leads to the production of tier 2 HIV-1–neutralizing antibodies, which increase in breadth and potency following Env immunization. In both genetically prone and experimentally induced mouse models of autoimmunity, increased serum levels of IgM anti-histone H2A autoantibodies significantly correlated with tier 2 HIV-1 neutralization, and anti-H2A antibody clones were found to neutralize HIV-1. These data demonstrate that breaching peripheral tolerance permits a cross-reactive HIV-1 autoantibody response able to neutralize HIV-1. PMID:28698284
Broderick, M P; Hansen, C J; Irvine, M; Metzgar, D; Campbell, K; Baker, C; Russell, K L
2010-02-01
Although several studies have shown a positive association between evidence of anti-adenovirus 36 (Ad-36) antibodies (Ad-36 exposure) and (1) obesity and (2) serum cholesterol in animals, there is limited research demonstrating this association in humans. There is also limited research on transmission, presentation and demographics of Ad-36 infection. (1) Body mass (body mass index (BMI)), (2) fasting serum cholesterol and triglyceride levels and (3) demographic characteristics were compared between Ad-36 seropositive and seronegative groups. The majority of subjects were matched as cases versus controls on a number of demographic variables. A total of 150 obese and 150 lean active-duty military personnel were studied. Subjects completed a questionnaire regarding demographic and behavioral characteristics. Subject serum samples were tested by serum neutralization assay for the presence of anti-Ad-36 antibodies. In all, 34% of obese and 39% of lean subjects had Ad-36 exposure, an insignificant difference. Serum cholesterol and triglyceride levels were significantly higher among the obese subjects than among the lean, but there were no associations between serum cholesterol and triglyceride levels and Ad-36 exposure. Positive associations were found between Ad-36 exposure and age, race and gender. The study stands in contrast to previous work that has shown a positive relationship between Ad-36 exposure and (1) obesity, and (2) levels of serum cholesterol and triglycerides. In this study there was no association in either case. Unanticipated relationships between Ad-36 exposure and age, race and gender were found, and this is the first time that such a link between Ad-36 exposure and demographics has been found.
Diagnosis of Barmah Forest Virus Infection by a Nested Real-Time SYBR Green RT-PCR Assay
Hueston, Linda; Toi, Cheryl S.; Jeoffreys, Neisha; Sorrell, Tania; Gilbert, Gwendolyn
2013-01-01
Barmah Forest virus (BFV) is a mosquito borne (+) ssRNA alphavirus found only in Australia. It causes rash, myalgia and arthralgia in humans and is usually diagnosed serologically. We developed a real-time PCR assay to detect BFV in an effort to improve diagnosis early in the course of infection. The limit of detection was 16 genome equivalents with a specificity of 100%. Fifty five serum samples from BFV-infected patients were tested by the PCR. 52 of 53 antibody-positive samples were PCR negative. Two culture-positive (neutralizing antibody negative) samples were positive on first round PCR, while one sample (IgM and neutralizing antibody strongly positive, IgG negative) was positive on second round PCR, suggesting that viral RNA is detectable and transiently present in early infection. PCR can provide results faster than culture, is capable of high throughput and by sequencing the PCR product strain variants can be characterized. PMID:23935816
Further circulation of West Nile and Usutu viruses in wild birds in Italy.
Llopis, Isis Victoriano; Rossi, Luca; Di Gennaro, Annapia; Mosca, Andrea; Teodori, Liana; Tomassone, Laura; Grego, Elena; Monaco, Federica; Lorusso, Alessio; Savini, Giovanni
2015-06-01
Usutu virus (USUV) and West Nile virus (WNV) are emerging pathogens that can cause neurological disease in humans. From March 2012 to June 2013, a sero-survey on wild birds was carried out to investigate the circulation of both viruses in Northwest (NW) Italy. Samples belonging to 47 different bird species have been collected using a volunteer based network and a wildlife rehabilitation center. Four of 297 serum samples had neutralizing antibodies against USUV (P=1.34%, IC 95% 0.36-3.4), while 10 of 233 samples tested positive for WNV (P=4.29%, IC 95% 2.07-7.75). Neutralizing antibodies for WNV were significantly more prevalent (p<0.001) in trans-Saharan migrants (P=21%, IC 95% 9.55-37.3) than in resident and short-distance birds, but no migratory habit-related differences were found for USUV. Antibodies in resident bird species suggest that both viruses are circulating in NW Italy. Copyright © 2015 Elsevier B.V. All rights reserved.
Siegel, L S
1988-01-01
To determine the immune status of persons receiving botulinum pentavalent (ABCDE) toxoid and to evaluate the effectiveness of the vaccine, we surveyed immunized individuals for neutralizing antibodies to type A and to type B botulinum toxins. After the primary series of three immunizations administered at 0, 2, and 12 weeks, 21 of 23 persons tested (91%) had a titer for type A that was greater than or equal to 0.08 international units (IU)/ml, and 18 (78%) had a titer for type B of greater than or equal to 0.02 IU/ml. (One international unit is defined as the amount of antibody neutralizing 10,000 mouse 50% lethal doses of type A or B botulinum toxin). Just before the first annual booster, 10 of 21 (48%) and 14 of 21 (67%) people lacked a detectable titer for type A and for type B, respectively. After the first booster, all individuals tested had a demonstrable titer to both types A and B. Of 77 persons who had previously received from one to eight boosts of the toxoid, 74 (96%) had an A titer of greater than or equal to 0.25 IU/ml and would not require an additional booster, according to the recommendations of the Centers for disease Control. However, only 44 of 77 (57%) had a B titer of greater than or equal to 0.25 IU/ml. In each group by booster number, even the group having had eight boosts, at least one person would require reimmunization on the basis of B titer. There was a wide range of antibody levels among individuals at the same point in the immunization scheme. Results from an enzyme linked immunosorbent assay, with purified type A or type B neurotoxin as the capture antigen, were compared with neutralization test results on 186 serum samples for type A and 168 samples for type B. Statistically, the correlation coefficients for results from the two assays were high (r = 0.69, P < 0.0001, for type A and r = 0.77, P < 0.0001, for type B). However, due to the wide dispersion of values obtained, using enzyme-linked immunosorbent assay results to predict neutralizing antibody levels is unwarranted. PMID:3235662
Shulman, Lester M; Martin, Javier; Sofer, Danit; Burns, Cara C; Manor, Yossi; Hindiyeh, Musa; Gavrilin, Eugene; Wilton, Thomas; Moran-Gilad, Jacob; Gamzo, Ronni; Mendelson, Ella; Grotto, Itamar
2015-04-01
Israel has >95% polio vaccine coverage with the last 9 birth cohorts immunized exclusively with inactivated polio vaccine (IPV). Using acute flaccid paralysis and routine, monthly countrywide environmental surveillance, no wild poliovirus circulation was detected between 1989 and February 2013, after which wild type 1 polioviruses South Asia genotype (WPV1-SOAS) have persistently circulated in southern Israel and intermittently in other areas without any paralytic cases as determined by intensified surveillance of environmental and human samples. We aimed to characterize antigenic and neurovirulence properties of WPV1-SOAS silently circulating in a highly vaccinated population. WPV1-SOAS capsid genes from environmental and stool surveillance isolates were sequenced, their neurovirulence was determined using transgenic mouse expressing the human poliovirus receptor (Tg21-PVR) mice, and their antigenicity was characterized by in vitro neutralization using human sera, epitope-specific monoclonal murine anti-oral poliovirus vaccine (OPV) antibodies, and sera from IPV-immunized rats and mice. WPV1 amino acid sequences in neutralizing epitopes varied from Sabin 1 and Mahoney, with little variation among WPV1 isolates. Neutralization by monoclonal antibodies against 3 of 4 OPV epitopes was lost. Three-fold lower geometric mean titers (Z = -4.018; P < .001, Wilcoxon signed-rank test) against WPV1 than against Mahoney in human serum correlated with 4- to 6-fold lower neutralization titers in serum from IPV-immunized rats and mice. WPV1-SOAS isolates were neurovirulent (50% intramuscular paralytic dose in Tg21-PVR mice: log10(7.0)). IPV-immunized mice were protected against WPV1-induced paralysis. Phenotypic and antigenic profile changes of WPV1-SOAS may have contributed to the intense silent transmission, whereas the reduced neurovirulence may have contributed to the absence of paralytic cases in the background of high population immunity. © The Author 2014. 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.
Measles & rubella outbreaks in Maharashtra State, India.
Vaidya, Sunil R; Kamble, Madhukar B; Chowdhury, Deepika T; Kumbhar, Neelakshi S
2016-02-01
Under the outbreak-based measles surveillance in Maharashtra State the National Institute of Virology at Pune receives 3-5 serum samples from each outbreak and samples from the local hospitals in Pune for laboratory diagnosis. This report describes one year data on the measles and rubella serology, virus isolation and genotyping. Maharashtra State Health Agencies investigated 98 suspected outbreaks between January-December 2013 in the 20 districts. Altogether, 491 serum samples were received from 20 districts and 126 suspected cases from local hospitals. Samples were tested for the measles and rubella IgM antibodies by commercial enzyme immunoassay (EIA). To understand the diagnostic utility, a subset of serum samples (n=53) was tested by measles focus reduction neutralization test (FRNT). Further, 37 throat swabs and 32 urine specimens were tested by measles reverse transcription (RT)-PCR and positive products were sequenced. Virus isolation was performed in Vero hSLAM cells. Of the 98 suspected measles outbreaks, 61 were confirmed as measles, 12 as rubella and 21 confirmed as the mixed outbreaks. Four outbreaks remained unconfirmed. Of the 126 cases from the local hospitals, 91 were confirmed for measles and three for rubella. Overall, 93.6 per cent (383/409) confirmed measles cases were in the age group of 0-15 yr. Measles virus was detected in 18 of 38 specimens obtained from the suspected cases. Sequencing of PCR products revealed circulation of D4 (n=9) and D8 (n=9) strains. Four measles viruses (three D4 & one D8) were isolated. Altogether, 94 measles and rubella outbreaks were confirmed in 2013 in the State of Maharasthra indicating the necessity to increase measles vaccine coverage in the State.
Measles & rubella outbreaks in Maharashtra State, India
Vaidya, Sunil R.; Kamble, Madhukar B.; Chowdhury, Deepika T.; Kumbhar, Neelakshi S.
2016-01-01
Background & objectives: Under the outbreak-based measles surveillance in Maharashtra State the National Institute of Virology at Pune receives 3-5 serum samples from each outbreak and samples from the local hospitals in Pune for laboratory diagnosis. This report describes one year data on the measles and rubella serology, virus isolation and genotyping. Methods: Maharashtra State Health Agencies investigated 98 suspected outbreaks between January-December 2013 in the 20 districts. Altogether, 491 serum samples were received from 20 districts and 126 suspected cases from local hospitals. Samples were tested for the measles and rubella IgM antibodies by commercial enzyme immunoassay (EIA). To understand the diagnostic utility, a subset of serum samples (n=53) was tested by measles focus reduction neutralization test (FRNT). Further, 37 throat swabs and 32 urine specimens were tested by measles reverse transcription (RT)-PCR and positive products were sequenced. Virus isolation was performed in Vero hSLAM cells. Results: Of the 98 suspected measles outbreaks, 61 were confirmed as measles, 12 as rubella and 21 confirmed as the mixed outbreaks. Four outbreaks remained unconfirmed. Of the 126 cases from the local hospitals, 91 were confirmed for measles and three for rubella. Overall, 93.6 per cent (383/409) confirmed measles cases were in the age group of 0-15 yr. Measles virus was detected in 18 of 38 specimens obtained from the suspected cases. Sequencing of PCR products revealed circulation of D4 (n=9) and D8 (n=9) strains. Four measles viruses (three D4 & one D8) were isolated. Interpretation & conclusions: Altogether, 94 measles and rubella outbreaks were confirmed in 2013 in the State of Maharasthra indicating the necessity to increase measles vaccine coverage in the State. PMID:27121521
Balamurugan, Vinayagamurthy; Sen, Arnab; Venkatesan, Gnanavel; Rajak, Kaushal Kishor; Bhanuprakash, Veerakyathappa; Singh, Raj Kumar
2012-08-01
In this study, the decay of maternal peste des petits ruminants virus (PPRV) antibodies in kids born to goats vaccinated with Asian lineage IV PPR vaccine and the efficacy of passive immunity against PPRV was assessed to determine the appropriate period for vaccination in kids. Serum samples collected from kids born to vaccinated, unvaccinated and infected goats at different time intervals were tested by PPR competitive ELISA and serum neutralization test (SNT). Maternal antibodies in kids were detectable up to 6 months with a decline trend from the third month onwards and receded below the protective level by the fourth month. The kid with an SN titre of 1:8 at the time of immunization showed significant PPRV specific antibody response (percentage inhibition of 76; SN titers >1:16), when tested on 21 day post-vaccination and was completely protected from infection upon virulent PPRV challenge. Similarly, the kid with 1:8 SN titers was completely protected from PPR infection on active challenge. Therefore, PPR vaccination is recommended in kids, aged 4 months and born to immunized or exposed goats. This could be a suitable period to avoid window of susceptibility in kids to PPRV and the effort to eliminate PPR infection from susceptible populations.
Dahiya, S S; Saini, M; Kumar, P; Gupta, P K
2011-01-01
A Sindbis virus replicon-based DNA vaccine containing VP2 gene of canine parvovirus (CPV) was delivered by Escherichia coli to elicit immune responses. The orally immunized dogs developed CPV-specific serum IgG and virus neutralizing antibody responses. The cellular immune responses analyzed using lymphocyte proliferation test and flow cytometry indicated CPV-specific sensitization of both CD3+CD4+ and CD3+CD8+ lymphocytes. This study demonstrated that the oral CPV DNA vaccine delivered by E. coli can be considered as a promising approach for vaccination of dogs against CPV.
Intradermal Inactivated Poliovirus Vaccine: A Preclinical Dose-Finding Study
Kouiavskaia, Diana; Mirochnitchenko, Olga; Dragunsky, Eugenia; Kochba, Efrat; Levin, Yotam; Troy, Stephanie; Chumakov, Konstantin
2015-01-01
Intradermal delivery of vaccines has been shown to result in dose sparing. We tested the ability of fractional doses of inactivated poliovirus vaccine (IPV) delivered intradermally to induce levels of serum poliovirus-neutralizing antibodies similar to immunization through the intramuscular route. Immunogenicity of fractional doses of IPV was studied by comparing intramuscular and intradermal immunization of Wistar rats using NanoPass MicronJet600 microneedles. Intradermal delivery of partial vaccine doses induced antibodies at titers comparable to those after immunization with full human dose delivered intramuscularly. The results suggest that intradermal delivery of IPV may lead to dose-sparing effect and reduction of the vaccination cost. PMID:25391313
Wang, Yimeng; O'Dell, Sijy; Turner, Hannah L.; Chiang, Chi-I; Lei, Lin; Guenaga, Javier; Wilson, Richard; Martinez-Murillo, Paola; Doria-Rose, Nicole; Ward, Andrew B.; Mascola, John R.; Wyatt, Richard T.; Karlsson Hedestam, Gunilla B.
2017-01-01
ABSTRACT Elicitation of broadly neutralizing antibody (bNAb) responses is a major goal for the development of an HIV-1 vaccine. Current HIV-1 envelope glycoprotein (Env) vaccine candidates elicit predominantly tier 1 and/or autologous tier 2 virus neutralizing antibody (NAb) responses, as well as weak and/or sporadic cross-reactive tier 2 virus NAb responses with unknown specificity. To delineate the specificity of vaccine-elicited cross-reactive tier 2 virus NAb responses, we performed single memory B cell sorting from the peripheral blood of a rhesus macaque immunized with YU2gp140-F trimers in adjuvant, using JR-FL SOSIP.664, a native Env trimer mimetic, as a sorting probe to isolate monoclonal Abs (MAbs). We found striking genetic and functional convergence of the SOSIP-sorted Ig repertoire, with predominant VH4 or VH5 gene family usage and Env V3 specificity. Of these vaccine-elicited V3-specific MAbs, nearly 20% (6/33) displayed cross-reactive tier 2 virus neutralization, which recapitulated the serum neutralization capacity. Substantial similarities in binding specificity, neutralization breadth and potency, and sequence/structural homology were observed between selected macaque cross-reactive V3 NAbs elicited by vaccination and prototypic V3 NAbs derived from natural infections in humans, highlighting the convergence of this subset of primate V3-specific B cell repertories. Our study demonstrated that cross-reactive primary virus neutralizing B cell lineages could be elicited by vaccination as detected using a standardized panel of tier 2 viruses. Whether these lineages could be expanded to acquire increased breadth and potency of neutralization merits further investigation. IMPORTANCE Elicitation of antibody responses capable of neutralizing diverse HIV-1 primary virus isolates (designated broadly neutralizing antibodies [bNAbs]) remains a high priority for the vaccine field. bNAb responses were so far observed only in response to natural infection within a subset of individuals. To achieve this goal, an improved understanding of vaccine-elicited responses, including at the monoclonal Ab level, is essential. Here, we isolated and characterized a panel of vaccine-elicited cross-reactive neutralizing MAbs targeting the Env V3 loop that moderately neutralized several primary viruses and recapitulated the serum neutralizing antibody response. Striking similarities between the cross-reactive V3 NAbs elicited by vaccination in macaques and natural infections in humans illustrate commonalities between the vaccine- and infection-induced responses to V3 and support the feasibility of exploring the V3 epitope as a HIV-1 vaccine target in nonhuman primates. PMID:28835491
Thomson, Russell; Finkelstein, Alan
2015-01-01
Apolipoprotein L-1 (APOL1), the trypanolytic factor of human serum, can lyse several African trypanosome species including Trypanosoma brucei brucei, but not the human-infective pathogens T. brucei rhodesiense and T. brucei gambiense, which are resistant to lysis by human serum. Lysis follows the uptake of APOL1 into acidic endosomes and is apparently caused by colloid-osmotic swelling due to an increased ion permeability of the plasma membrane. Here we demonstrate that nanogram quantities of full-length recombinant APOL1 induce ideally cation-selective macroscopic conductances in planar lipid bilayers. The conductances were highly sensitive to pH: their induction required acidic pH (pH 5.3), but their magnitude could be increased 3,000-fold upon alkalinization of the milieu (pKa = 7.1). We show that this phenomenon can be attributed to the association of APOL1 with the bilayer at acidic pH, followed by the opening of APOL1-induced cation-selective channels upon pH neutralization. Furthermore, the conductance increase at neutral pH (but not membrane association at acidic pH) was prevented by the interaction of APOL1 with the serum resistance-associated protein, which is produced by T. brucei rhodesiense and prevents trypanosome lysis by APOL1. These data are consistent with a model of lysis that involves endocytic recycling of APOL1 and the formation of cation-selective channels, at neutral pH, in the parasite plasma membrane. PMID:25730870
Gringeri, A; Santagostino, E; Mannucci, P M; Siracusano, L; Marinoni, A; Criscuolo, M; Carcagno, M; Fall, L S; M'Bika, J P; Bizzini, B
1995-05-01
A randomized, placebo-controlled trial was designed to evaluate safety and immunogenicity of an anti-cytokine vaccine in high risk HIV-positive patients. This strategy was aimed to modulate the impaired cytokine regulation in AIDS. Twelve asymptomatic patients on antiretroviral therapy for at least 1 year and with CD4 cell counts between 100-300/mm3 were randomized to receive adjuvanted formol-inactivated interferon alpha-2a (IFN alpha) and continue the current antiretroviral treatment, whatever it was, or to receive the adjuvant alone and the current antiretroviral treatment. All patients received 4 i.m. injections monthly, followed by booster injections every 3 months. Clinical status, immunology and virology were monitored. Immune response to vaccination was evaluated in term of antibody detection (ELISA) and serum anti-IFN alpha neutralizing capacity. Only local discomfort and transient fever were reported. All vaccines except one showed increased levels of anti-IFN alpha Abs and developed serum IFN alpha neutralizing capacity. Viral load did not increase in vaccinees while it remained unchanged or even increased in placebo-treated patients. None of them showed HIV-related symptoms and all had their CD4 cell counts stabilized over 18 months, whereas 2 placebo-treated patients developed full-blow AIDS. In conclusion, anti-IFN alpha vaccine was safe and immunogenic. Stable clinical and immunological status over 18 months was observed in vaccinees coupled to increased serum IFN alpha neutralizing capacity.
Sobarzo, Ariel; Stonier, Spencer W.; Herbert, Andrew S.; Ochayon, David E.; Kuehne, Ana I.; Eskira, Yael; Fedida-Metula, Shlomit; Tali, Neta; Lewis, Eli C.; Egesa, Moses; Cose, Stephen; Lutwama, Julius Julian; Yavelsky, Victoria; Dye, John M.; Lobel, Leslie
2016-01-01
Robust humoral and cellular immunity are critical for survival in humans during an ebolavirus infection. However, the interplay between these two arms of immunity is poorly understood. To address this, we examined residual immune responses in survivors of the Sudan virus (SUDV) outbreak in Gulu, Uganda (2000–2001). Cytokine and chemokine expression levels in SUDV stimulated whole blood cultures were assessed by multiplex ELISA and flow cytometry. Antibody and corresponding neutralization titers were also determined. Flow cytometry and multiplex ELISA results demonstrated significantly higher levels of cytokine and chemokine responses in survivors with serological neutralizing activity. This correspondence was not detected in survivors with serum reactivity to SUDV but without neutralization activity. This previously undefined relationship between memory CD4 T cell responses and serological neutralizing capacity in SUDV survivors is key for understanding long lasting immunity in survivors of filovirus infections. PMID:27187443
Sobarzo, Ariel; Stonier, Spencer W; Herbert, Andrew S; Ochayon, David E; Kuehne, Ana I; Eskira, Yael; Fedida-Metula, Shlomit; Tali, Neta; Lewis, Eli C; Egesa, Moses; Cose, Stephen; Lutwama, Julius Julian; Yavelsky, Victoria; Dye, John M; Lobel, Leslie
2016-05-11
Robust humoral and cellular immunity are critical for survival in humans during an ebolavirus infection. However, the interplay between these two arms of immunity is poorly understood. To address this, we examined residual immune responses in survivors of the Sudan virus (SUDV) outbreak in Gulu, Uganda (2000-2001). Cytokine and chemokine expression levels in SUDV stimulated whole blood cultures were assessed by multiplex ELISA and flow cytometry. Antibody and corresponding neutralization titers were also determined. Flow cytometry and multiplex ELISA results demonstrated significantly higher levels of cytokine and chemokine responses in survivors with serological neutralizing activity. This correspondence was not detected in survivors with serum reactivity to SUDV but without neutralization activity. This previously undefined relationship between memory CD4 T cell responses and serological neutralizing capacity in SUDV survivors is key for understanding long lasting immunity in survivors of filovirus infections.
Immunogenicity of an interferon-beta1a product.
Kauffman, M A; Sterin-Prync, A; Papouchado, M; González, E; Vidal, A J; Grossberg, S E; Chuppa, S; Odoriz, B; Vrech, C; Diez, R A; Ferro, H H
2011-01-01
In order to determine whether Blastoferon®, a biosimilar interferon (IFN)- beta 1a formulation, shares epitopes with other known IFN-beta products, a series of neutralization bioassays were performed with a set of well-characterized anti-IFN- beta monoclonal antibodies and human sera (World Health Organization Reference Reagents). The bioassay was the interferon-induced inhibition of virus cytopathic effect on human cells in culture (EMC virus and A-549 cells). Computer-calculated results were reported as Tenfold Reduction Units (TRU)/ml. To further assess Blastoferon® immunogenicity, in vivo production of anti-IFN beta antibodies was determined in sera of patients included in the pharmacovigilance plan of Blastoferon® by the level of IFN- beta 1a binding antibodies (by enzyme immunoassay -EIA) and neutralizing antibodies (in the Wish-VSV system). The highly characterized neutralizing monoclonal antibodies A1 and A5 that bind to specific regions of the IFN- beta molecule reacted positively with the three beta 1a IFNs: Blastoferon®, Rebif®, and the IFN- beta WHO Second International Standard 00/572. As expected, the non-neutralizing monoclonal antibodies B4 and B7 did not neutralize any of the IFN- beta preparations. The commercially available monoclonal antibody B-02 reacted essentially equally with Rebif® and Blastoferon®. The WHO Reference Reagent human serum anti-IFN- beta polyclonal antibody neutralized all the IFN- beta products, whereas the WHO Reference Reagent human serum anti-IFN-alpha polyclonal antibody G037-501-572 appropriately failed to react with any of the IFN- beta products. On the basis of in vitro reactivity with known, well-characterized monoclonal and polyclonal antibody preparations, Blastoferon® shares immunological determinants with other human interferon- beta products, especially IFN- beta 1a. In vivo antibodies were detected by EIA in 72.9% of 37 chronically treated multiple sclerosis patients, whereas neutralizing antibodies were found in 8.1% of them. Blastoferon® appears to have immunological characteristics comparable to other IFN- beta 1a products.
Gao, Jiming; Chen, Junhao; Si, Xingkui; Xie, Zhijing; Zhu, Yanli; Zhang, Xingxiao; Wang, Shujing; Jiang, Shijin
2012-08-01
To investigate the relationship of the variation of virulence and the external capsid proteins of the pandemic duck hepatitis A virus type 1 (DHAV-1) isolates, the virulence, cross neutralization assays and the complete sequence of the virion protein 1 (VP1) gene of nine virulent DHAV-1 strains, which were isolated from infected ducklings with clinical symptoms in Shandong province of China in 2007-2008, were tested. The fifth generation duck embryo allantoic liquids of the 9 isolates were tested on 12-day-old duck embryos and on 7-day-old ducklings for the median embryonal lethal doses (ELD(50)s) and the median lethal doses (LD(50)s), respectively. The results showed that the ELD(50)s of embryonic duck eggs of the 9 DHAV-1 isolates were between 1.9 × 10(6)/mL to 1.44 × 10(7)/mL, while the LD(50)s were 2.39 × 10(5)/mL to 6.15 × 10(6)/mL. Cross-neutralization tests revealed that the 9 DHAV-1 isolates were completely neutralized by the standard serum and the hyperimmune sera against the 9 DHAV-1 isolates, respectively. Compared with other virulent, moderate virulent, attenuated vaccine and mild strains, the VP1 genes of the 9 strains shared 89.8%-99.7% similarity at the nucleotide level and 92.4%-99.6% at amino acid level with other DHAV-1 strains. There were three hypervariable regions at the C-terminus (aa 158-160, 180-193 and 205-219) and other variable points in VP1 protein, but which didn't cause virulence of DHAV-1 change.
Natural exposure of bats in Grenada to rabies virus
Zieger, Ulrike; Cheetham, Sonia; Santana, Sharlene E.; Leiser-Miller, Leith; Matthew-Belmar, Vanessa; Goharriz, Hooman; Fooks, Anthony R.
2017-01-01
ABSTRACT Introduction: Grenada is a rabies endemic country, where terrestrial rabies is maintained in the small Indian mongoose (Herpestes auropunctatus). The role of bats in the epidemiology of rabies in Grenada is unknown. A 1974 report described one rabies virus positive Jamaican fruit bat (Artibeus jamaicensis), and a high seroprevalence in this species. In the current study, the natural exposure to rabies virus in Grenadian bats was re-evaluated. It is postulated that bats serve as a natural rabies reservoir, probably circulating a bat-specific rabies virus variant. Material and methods: Bats were trapped in 2015 in all six parishes of Grenada using mist- and hand nets. For the detection of rabies virus in brain tissue, the direct fluorescent antibody test (dFAT) and the reverse transcription polymerase chain reaction (RT-PCR) were used. Serum neutralizing antibodies were determined using the fluorescent antibody virus neutralization test (FAVN). Results and discussion: Brain tissue and sera from 111 insectivorous and frugivorous bats belonging to four species were tested (52 Artibeus jamaicensis, two Artibeus lituratus, 33 Glossophaga longirostris, 24 Molossus molossus). Rabies virus antigen and genomic RNA were not detected in brain tissues. Rabies virus neutralizing antibodies were detected in the sera of eight A. jamaicensis in four of the six parishes. Bats in Grenada continue to show natural exposure to rabies virus. As rabies virus was not isolated in this study, serology alone is not sufficient to determine the strain of rabies virus circulating in A. jamaicensis bats in Grenada. Conclusion: Artibeus jamaicensis appears to play a role as a reservoir bat species, which is of public health concern in Grenada. Dispersion of bats to neighboring islands is possible and serological bat surveys should be initiated in these neighboring states, especially in those areas that are free of rabies in terrestrial mammals. PMID:28804595
Ehrengut, W; Georges, A M; André, F E
1983-04-01
The immunogenicity and reactogenicity of the Urabe Am 9 mumps virus vaccine strain were studied after the administration of different doses of the vaccine to 197 children ranging in age from seven and a half months to nine years and without a history of mumps. There was no effect of dose on the response in serum neutralizing antibodies in the range of 10(2.9) to 10(4.7) TCID50/dose. In the 90 subjects without detectable serum neutralization antibodies before vaccination seroconversion was obtained in 94.4% after 42 days. Half of a group of 34 seropositive children who were tested also showed a fourfold or greater rise in antibodies. Persistence of vaccine-enhanced haemagluttinin-inhibition (EHI) antibodies was satisfactory as only two of 46 vaccinees followed-up for between 27 and 32 months had undetectable levels of EHI antibodies and the geometric mean titre of vaccine-induced EHI antibodies had only fallen to about one-third by 32 months after vaccination. Although there was serological evidence of a subclinical re-infection in three subjects, to date none of the vaccinees has had clinical mumps indicating that the vaccine confers protection against disease. The vaccine was well tolerated. Furthermore, the majority of the few 'reactions' reported were probably not vaccine-related. It is concluded that the Urabe Am 9 is an acceptable strain for use in live mumps vaccines.
Henry, C J; McCaw, D L; Brock, K V; Stoker, A M; Tyler, J W; Tate, D J; Higginbotham, M L
2001-11-01
To determine the association between cancer chemotherapy and serum canine distemper virus (CDV), canine parvovirus (CPV), and rabies virus antibody titers in tumor-bearing dogs. Prospective study. 21 client-owned dogs with various malignancies and 16 client-owned dogs with lymphoma. In study A, serum antibody titers were measured by use of hemagglutination inhibition (CPV titers) or serum neutralization (CDV titers) before and at least 1 month after initiation of chemotherapy. Baseline values were compared with values obtained from a control population of 122 healthy dogs seen for routine revaccination. Titers were considered protective at > or = 1:96 for CDV and > or = 1:80 for CPV. In study B, serum IgG titers were measured by use of immunofluorescent assay (CDV and CPV titers) and rapid fluorescent focus inhibition test (RFFIT, rabies titers) at baseline and again at weeks 5, 8, and 24 of a standard chemotherapy protocol for treatment of lymphoma. An IgG titer of > or = 1:50 was considered protective for CPV and CDV. An RFFIT titer of > or = 0.5 U/ml was considered protective for rabies virus. Significant changes were not detected in CDV, CPV, and rabies virus titers following chemotherapy in tumor-bearing dogs. Results suggest that established immunity to CDV, CPV, and rabies virus from previous vaccination is not significantly compromised by standard chemotherapy used to treat tumor-bearing dogs.
Einstein, Mark H; Baron, Mira; Levin, Myron J; Chatterjee, Archana; Edwards, Robert P; Zepp, Fred; Carletti, Isabelle; Dessy, Francis J; Trofa, Andrew F; Schuind, Anne; Dubin, Gary
2009-10-01
This observer-blind study compared the prophylactic human papillomavirus (HPV) vaccines, Cervarix (GlaxoSmithKline) and Gardasil (Merck), by assessing immunogenicity and safety through one month after completion of the three-dose vaccination course. Women (n = 1106) were stratified by age (18-26, 27-35, 36-45 years) and randomized (1:1) to receive Cervarix (Months 0, 1, 6) or Gardasil (Months 0, 2, 6). At Month 7 after first vaccination, all women in the according-to-protocol cohort who were seronegative/DNA negative before vaccination for the HPV type analyzed had seroconverted for HPV-16 and HPV-18 serum neutralizing antibodies, as measured by pseudovirion-based neutralization assay (PBNA), except for two women aged 27-35 years in the Gardasil group who did not seroconvert for HPV-18 (98%). Geometric mean titers of serum neutralizing antibodies ranged from 2.3-4.8-fold higher for HPV-16 and 6.8-9.1-fold higher for HPV-18 after vaccination with Cervarix compared with Gardasil, across all age strata. In the total vaccinated cohort (all women who received at least one vaccine dose, regardless of their serological and DNA status prior to vaccination), Cervarix induced significantly higher serum neutralizing antibody titers in all age strata (p < 0.0001). Positivity rates for anti-HPV-16 and -18 neutralizing antibodies in cervicovaginal secretions and circulating HPV-16 and -18 specific memory B-cell frequencies were also higher after vaccination with Cervarix compared with Gardasil. Both vaccines were generally well tolerated. The incidence of unsolicited adverse events was comparable between vaccinated groups. The incidence of solicited symptoms was generally higher after Cervarix, injection site reactions being most common. However, compliance rates with the three-dose schedules were similarly high (>or= 84%) for both vaccines. Although the importance of differences in magnitude of immune response between these vaccines is unknown, they may represent determinants of duration of protection against HPV-16/18. Long-term studies evaluating duration of efficacy after vaccination are needed for both vaccines.
Ueno, Hiroshi M; Urazono, Hiroshi; Kobayashi, Toshiya
2014-02-15
The iron-lactoferrin complex is a common food ingredient because of its iron-solubilizing capability in the presence of hydrogen carbonate ions. However, it is unclear whether the formation of a stable iron-binding complex is limited to lactoferrin. In this study, we investigated the effects of bovine serum albumin (BSA) on iron solubility and iron-catalyzed lipid oxidation in the presence of hydrogen carbonate ions. BSA could solubilize >100-fold molar equivalents of iron at neutral pH, exceeding the specific metal-binding property of BSA. This iron-solubilizing capability of BSA was impaired by thermally denaturing BSA at ≥ 70 °C for 10 min at pH 8.5. The resulting iron-BSA complex inhibited iron-catalyzed oxidation of soybean oil in a water-in-oil emulsion measured using the Rancimat test. Our study is the first to show that BSA, like lactoferrin, forms a soluble iron-binding complex in the presence of hydrogen carbonate ions. Copyright © 2013 Elsevier Ltd. All rights reserved.
A novel mutation in PNPLA2 leading to neutral lipid storage disease with myopathy.
Ash, Daniel B; Papadimitriou, Dimitra; Hays, Arthur P; Dimauro, Salvatore; Hirano, Michio
2012-09-01
Mutations in PNPLA2, a gene encoding adipose triglyceride lipase, lead to neutral lipid storage disease with myopathy. To report the clinical and molecular features of a case of neutral lipid storage disease with myopathy resulting from a novel mutation in PNPLA2. Case report. University hospital. A 65-year-old man with progressive muscle weakness and high serum creatine kinase levels. Direct sequencing of the PNPLA2 gene. Identification of a novel homozygous mutation in the patient's PNPLA2 gene confirmed the suspected diagnosis of neutral lipid storage disease with myopathy. Screening of the PNPLA2 gene should be considered for patients presenting with high levels of creatine kinase, progressive muscle weakness, and systemic lipid accumulation. The presence of Jordans anomaly can be a strong diagnostic clue.
Vance, David J.; Tremblay, Jacqueline M.; Mantis, Nicholas J.; Shoemaker, Charles B.
2013-01-01
In an effort to engineer countermeasures for the category B toxin ricin, we produced and characterized a collection of epitopic tagged, heavy chain-only antibody VH domains (VHHs) specific for the ricin enzymatic (RTA) and binding (RTB) subunits. Among the 20 unique ricin-specific VHHs we identified, six had toxin-neutralizing activity: five specific for RTA and one specific for RTB. Three neutralizing RTA-specific VHHs were each linked via a short peptide spacer to the sole neutralizing anti-RTB VHH to create VHH “heterodimers.” As compared with equimolar concentrations of their respective monovalent monomers, all three VHH heterodimers had higher affinities for ricin and, in the case of heterodimer D10/B7, a 6-fold increase in in vitro toxin-neutralizing activity. When passively administered to mice at a 4:1 heterodimer:toxin ratio, D10/B7 conferred 100% survival in response to a 10 × LD50 ricin challenge, whereas a 2:1 heterodimer:toxin ratio conferred 20% survival. However, complete survival was achievable when the low dose of D10/B7 was combined with an IgG1 anti-epitopic tag monoclonal antibody, possibly because decorating the toxin with up to four IgGs promoted serum clearance. The two additional ricin-specific heterodimers, when tested in vivo, provided equal or greater passive protection than D10/B7, thereby warranting further investigation of all three heterodimers as possible therapeutics. PMID:24202178
Vance, David J; Tremblay, Jacqueline M; Mantis, Nicholas J; Shoemaker, Charles B
2013-12-20
In an effort to engineer countermeasures for the category B toxin ricin, we produced and characterized a collection of epitopic tagged, heavy chain-only antibody VH domains (VHHs) specific for the ricin enzymatic (RTA) and binding (RTB) subunits. Among the 20 unique ricin-specific VHHs we identified, six had toxin-neutralizing activity: five specific for RTA and one specific for RTB. Three neutralizing RTA-specific VHHs were each linked via a short peptide spacer to the sole neutralizing anti-RTB VHH to create VHH "heterodimers." As compared with equimolar concentrations of their respective monovalent monomers, all three VHH heterodimers had higher affinities for ricin and, in the case of heterodimer D10/B7, a 6-fold increase in in vitro toxin-neutralizing activity. When passively administered to mice at a 4:1 heterodimer:toxin ratio, D10/B7 conferred 100% survival in response to a 10 × LD50 ricin challenge, whereas a 2:1 heterodimer:toxin ratio conferred 20% survival. However, complete survival was achievable when the low dose of D10/B7 was combined with an IgG1 anti-epitopic tag monoclonal antibody, possibly because decorating the toxin with up to four IgGs promoted serum clearance. The two additional ricin-specific heterodimers, when tested in vivo, provided equal or greater passive protection than D10/B7, thereby warranting further investigation of all three heterodimers as possible therapeutics.
Aggregate complexes of HIV-1 induced by multimeric antibodies.
Stieh, Daniel J; King, Deborah F; Klein, Katja; Liu, Pinghuang; Shen, Xiaoying; Hwang, Kwan Ki; Ferrari, Guido; Montefiori, David C; Haynes, Barton; Pitisuttithum, Punnee; Kaewkungwal, Jaranit; Nitayaphan, Sorachai; Rerks-Ngarm, Supachai; Michael, Nelson L; Robb, Merlin L; Kim, Jerome H; Denny, Thomas N; Tomaras, Georgia D; Shattock, Robin J
2014-10-02
Antibody mediated viral aggregation may impede viral transfer across mucosal surfaces by hindering viral movement in mucus, preventing transcytosis, or reducing inter-cellular penetration of epithelia thereby limiting access to susceptible mucosal CD4 T cells and dendritic cells. These functions may work together to provide effective immune exclusion of virus from mucosal tissue; however little is known about the antibody characteristics required to induce HIV aggregation. Such knowledge may be critical to the design of successful immunization strategies to facilitate viral immune exclusion at the mucosal portals of entry. The potential of neutralizing and non-neutralizing IgG and IgA monoclonals (mAbs) to induce HIV-1 aggregation was assessed by Dynamic light scattering (DLS). Although neutralizing and non-neutralizing IgG mAbs and polyclonal HIV-Ig efficiently aggregated soluble Env trimers, they were not capable of forming viral aggregates. In contrast, dimeric (but not monomeric) IgA mAbs induced stable viral aggregate populations that could be separated from uncomplexed virions. Epitope specificity influenced both the degree of aggregation and formation of higher order complexes by dIgA. IgA purified from serum of uninfected RV144 vaccine trial responders were able to efficiently opsonize viral particles in the absence of significant aggregation, reflective of monomeric IgA. These results collectively demonstrate that dIgA is capable of forming stable viral aggregates providing a plausible basis for testing the effectiveness of aggregation as a potential protection mechanism at the mucosal portals of viral entry.
Falsey, Ann R; Koval, Christine; DeVincenzo, John P; Walsh, Edward E
2017-04-01
Respiratory syncytial virus (RSV) may cause fatal lower respiratory tract infection (LRTI) in immunocompromised patients. Ribavirin with or without standard intravenous immunoglobulin (IVIG) is frequently given although efficacy is debated. Infusion of IVIG with high levels of neutralizing antibody against RSV may offer benefit in these patients. RI-001 contains standardized levels of high-titer anti-RSV neutralizing antibody and was provided for compassionate use to 15 patients with RSV LRTI who either failed conventional therapy or had significant risk of progression. Patients were treated on day 1 with RI-001 1500 mg/kg, followed 2 days later with 750 mg/kg. Pre- and post-infusion sera were measured for RSV neutralizing antibody. Patient data were analyzed for safety related to infusion of RI-001, and clinical outcomes. Patients ranged in age from 2 months to 71 years and 80% had hematologic malignancy or were bone marrow or hematopoietic stem cell transplant recipients. Administration was well tolerated. Pre-infusion neutralizing titers ranged from 51 to 1765 geometric mean titer (mean 646±519) and all patients demonstrated at least a 4-fold rise (mean 6410±4470) 5-10 days post infusion. Eleven of 15 improved and were discharged from the hospital. Days from positive RSV test to RI-001 treatment was shorter in survivors compared to non-survivors (4.4±2.8 vs. 20.3±21.0 days, P=.02). Administration of RI-001 was well tolerated and resulted in significant increases in serum neutralizing antibody titers to RSV. Our data suggest that early identification of RSV and treatment with RI-001 may offer benefit. © 2017 The Authors. Transplant Infectious Disease Published by John Wiley & Sons Ltd.
Pornmanee, Piboon; Sánchez, Elda E.; López, Gonzalo; Petsom, Amorn; Khow, Orawan; Pakmanee, Narumol; Chanhome, Lawan; Sangvanich, Polkit; Pérez, John C.
2012-01-01
Malayan pit viper (Calloselasma rhodostoma) envenomation is a major health problem in South East Asia. During envenomation, venom components mainly affect the hemostatic system. The sera from the North American Virginia opossums (Didelphis virginiana) were able to neutralize the venom of the Malayan pit viper. These natural inhibitors could be explored as potential therapeutics against envenomations of a variety of venomous snake species in different geographical habitats. PMID:18617212
Liu, G Frank; Hille, Darcy; Kaplan, Susan S; Goveia, Michelle G
2017-10-03
Although clinical trials of the pentavalent rotavirus vaccine (RotaTeq®, RV5) have demonstrated efficacy against RV gastroenteritis (RGE) in low and high-income settings, a clear correlate of protection or a measure of immune response that could predict efficacy has yet to be identified. This is the first time that immunogenicity data with both serum neutralized antibody (SNA) titers and anti-RV IgA titers from several clinical efficacy trials were pooled to provide a unique context for evaluating the correlation between immunogenicity and RGE risk or efficacy of RV5. The correlation between immunogenicity and RGE risk is evaluated with data at the individual subject level. The analyses show that higher Postdose 3 (PD3) G1 SNA titers are associated with lower odds of contracting any RGE. The correlation between immunogenicity and efficacy is assessed using aggregated population level data, which shows higher efficacy associated with higher PD3 G1 SNA geometric mean titer (GMT) ratio (between RV5 and placebo) and PD3 serum anti-RV IgA GMT ratio. Among high-income countries, efficacy plateaus over the range of PD3 G1 SNA GMT ratios and PD3 serum anti-RV IgA GMT ratios. From both individual- and population-level analyses, PD3 G1 SNA titers correlated most closely with the RGE risk or efficacy for RV5.
Production of the First Effective Hyperimmune Equine Serum Antivenom against Africanized Bees
Santos, Keity Souza; Stephano, Marco Antonio; Marcelino, José Roberto; Ferreira, Virginia Maria Resende; Rocha, Thalita; Caricati, Celso; Higashi, Hisako Gondo; Moro, Ana Maria; Kalil, Jorge Elias; Malaspina, Osmar; Castro, Fabio Fernandes Morato; Palma, Mário Sérgio
2013-01-01
Victims of massive bee attacks become extremely ill, presenting symptoms ranging from dizziness and headache to acute renal failure and multiple organ failure that can lead to death. Previous attempts to develop specific antivenom to treat these victims have been unsuccessful. We herein report a F(ab)´2-based antivenom raised in horse as a potential new treatment for victims of multiple bee stings. The final product contains high specific IgG titers and is effective in neutralizing toxic effects, such as hemolysis, cytotoxicity and myotoxicity. The assessment of neutralization was revised and hemolysis, the primary toxic effect of these stings, was fully neutralized in vivo for the first time. PMID:24236166
Hahn-Zoric, M; Carlsson, B; Jeansson, S; Ekre, H P; Osterhaus, A D; Roberton, D; Hanson, L A
1993-05-01
Our previous studies have suggested that fetal antibody production can be induced by maternal antiidiotypic antibodies transferred to the fetus via the placenta. We tested commercial Ig, sera, and milk for the presence of anti-idiotypic antibodies to poliovirus type 1, using affinity chromatography combined with ELISA systems and virus neutralization techniques. Our results indicate that commercial Ig, serum, and milk samples contain antibodies recognizing idiotypic determinants on antibodies to poliovirus. Several lines of evidence support this conclusion. Thus, in an ELISA with poliovirus as a solid phase, binding of specific antibodies could be inhibited by addition of an eluate from the Ig preparation containing anti-idiotypic antibodies against poliovirus type 1. Also, antiidiotypic antibodies from pooled human Ig, serum, and colostrum samples against poliovirus bound directly to solid-phase-attached MAb against poliovirus type 1. In addition, in a competitive inhibition ELISA, where antiidiotypic antibodies isolated from the Ig preparation competed with the poliovirus antigen for binding to monoclonal or polyclonal idiotypic antibodies on the solid phase, inhibition of antigen binding was seen at low antigen concentrations. When single-donor serum or milk was used, this inhibition was even more pronounced and could be demonstrated at almost all antigen concentrations. The finding that anti-idiotypes are present in maternal serum and milk imply, in agreement with our previous studies, that anti-idiotypes may actively induce a specific immune response in the fetus without previous exposure to the antigen by being transferred across the placenta or by being passively transferred to the newborn via mother's milk.
Latency of Herpes Simplex Virus in Absence of Neutralizing Antibody: Model for Reactivation
NASA Astrophysics Data System (ADS)
Sekizawa, Tsuyoshi; Openshaw, Harry; Wohlenberg, Charles; Notkins, Abner Louis
1980-11-01
Mice inoculated with herpes simplex virus (type 1) by the lip or corneal route and then passively immunized with rabbit antibody to herpes simplex virus developed a latent infection in the trigeminal ganglia within 96 hours. Neutralizing antibody to herpes simplex virus was cleared from the circulation and could not be detected in most of these mice after 2 months. Examination of ganglia from the antibody-negative mice revealed latent virus in over 90 percent of the animals, indicating that serum neutralizing antibody is not necessary to maintain the latent state. When the lips or corneas of these mice were traumatized, viral reactivation occurred in up to 90 percent of the mice, as demonstrated by the appearance of neutralizing antibody. This study provides a model for identifying factors that trigger viral reactivation.
Effects of different levels of coconut fiber on blood glucose, serum insulin and minerals in rats.
Sindurani, J A; Rajamohan, T
2000-01-01
The effect of neutral detergent fiber (NDF) from coconut kernel (Cocos nucifera L) in rats fed 5%, 15% and 30% level on the concentration of blood glucose, serum insulin and excretion of minerals was studied. Increase in the intake of fiber resulted in significant decrease in the level of blood glucose and serum insulin. Faecal excretion of Cu, Cr, Mn, Mg, Zn and Ca was found to increase in rats fed different levels of coconut fiber when compared to fiber free group. The result of the present investigation suggest that inclusion of coconut fiber in the diet results in significant hypoglycemic action.
Reis, R S; Dalle Molle, R; Machado, T D; Mucellini, A B; Rodrigues, D M; Bortoluzzi, A; Bigonha, S M; Toazza, R; Salum, G A; Minuzzi, L; Buchweitz, A; Franco, A R; Pelúzio, M C G; Manfro, G G; Silveira, P P
2016-03-15
The goal of the present study was to investigate whether intrauterine growth restriction (IUGR) affects brain responses to palatable foods and whether docosahexaenoic acid (DHA, an omega-3 fatty acid that is a primary structural component of the human brain) serum levels moderate the association between IUGR and brain and behavioral responses to palatable foods. Brain responses to palatable foods were investigated using a functional magnetic resonance imaging task in which participants were shown palatable foods, neutral foods and non-food items. Serum DHA was quantified in blood samples, and birth weight ratio (BWR) was used as a proxy for IUGR. The Dutch Eating Behavior Questionnaire (DEBQ) was used to evaluate eating behaviors. In the contrast palatable food > neutral items, we found an activation in the right superior frontal gyrus with BWR as the most important predictor; the lower the BWR (indicative of IUGR), the greater the activation of this region involved in impulse control/decision making facing the viewing of palatable food pictures versus neutral items. At the behavioral level, a general linear model predicting external eating using the DEBQ showed a significant interaction between DHA and IUGR status; in IUGR individuals, the higher the serum DHA, the lower is external eating. In conclusion, we suggest that IUGR moderates brain responses when facing stimuli related to palatable foods, activating an area related to impulse control. Moreover, higher intake of n-3 PUFAs can protect IUGR individuals from developing inappropriate eating behaviors, the putative mechanism of protection would involve decreasing intake in response to external food cues in adolescents/young adults.
Reis, R S; Dalle Molle, R; Machado, T D; Mucellini, A B; Rodrigues, D M; Bortoluzzi, A; Bigonha, S M; Toazza, R; Salum, G A; Minuzzi, L; Buchweitz, A; Franco, A R; Pelúzio, M C G; Manfro, G G; Silveira, P P
2016-01-01
The goal of the present study was to investigate whether intrauterine growth restriction (IUGR) affects brain responses to palatable foods and whether docosahexaenoic acid (DHA, an omega-3 fatty acid that is a primary structural component of the human brain) serum levels moderate the association between IUGR and brain and behavioral responses to palatable foods. Brain responses to palatable foods were investigated using a functional magnetic resonance imaging task in which participants were shown palatable foods, neutral foods and non-food items. Serum DHA was quantified in blood samples, and birth weight ratio (BWR) was used as a proxy for IUGR. The Dutch Eating Behavior Questionnaire (DEBQ) was used to evaluate eating behaviors. In the contrast palatable food > neutral items, we found an activation in the right superior frontal gyrus with BWR as the most important predictor; the lower the BWR (indicative of IUGR), the greater the activation of this region involved in impulse control/decision making facing the viewing of palatable food pictures versus neutral items. At the behavioral level, a general linear model predicting external eating using the DEBQ showed a significant interaction between DHA and IUGR status; in IUGR individuals, the higher the serum DHA, the lower is external eating. In conclusion, we suggest that IUGR moderates brain responses when facing stimuli related to palatable foods, activating an area related to impulse control. Moreover, higher intake of n-3 PUFAs can protect IUGR individuals from developing inappropriate eating behaviors, the putative mechanism of protection would involve decreasing intake in response to external food cues in adolescents/young adults. PMID:26978737
deCamp, Allan; Hraber, Peter; Bailer, Robert T.; Seaman, Michael S.; Ochsenbauer, Christina; Kappes, John; Gottardo, Raphael; Edlefsen, Paul; Self, Steve; Tang, Haili; Greene, Kelli; Gao, Hongmei; Daniell, Xiaoju; Sarzotti-Kelsoe, Marcella; Gorny, Miroslaw K.; Zolla-Pazner, Susan; LaBranche, Celia C.; Mascola, John R.; Korber, Bette T.
2014-01-01
ABSTRACT Standardized assessments of HIV-1 vaccine-elicited neutralizing antibody responses are complicated by the genetic and antigenic variability of the viral envelope glycoproteins (Envs). To address these issues, suitable reference strains are needed that are representative of the global epidemic. Several panels have been recommended previously, but no clear answers have been available on how many and which strains are best suited for this purpose. We used a statistical model selection method to identify a global panel of reference Env clones from among 219 Env-pseudotyped viruses assayed in TZM-bl cells with sera from 205 HIV-1-infected individuals. The Envs and sera were sampled globally from diverse geographic locations and represented all major genetic subtypes and circulating recombinant forms of the virus. Assays with a panel size of only nine viruses adequately represented the spectrum of HIV-1 serum neutralizing activity seen with the larger panel of 219 viruses. An optimal panel of nine viruses was selected and augmented with three additional viruses for greater genetic and antigenic coverage. The spectrum of HIV-1 serum neutralizing activity seen with the final 12-virus panel closely approximated the activity seen with subtype-matched viruses. Moreover, the final panel was highly sensitive for detection of many of the known broadly neutralizing antibodies. For broader assay applications, all 12 Env clones were converted to infectious molecular clones using a proviral backbone carrying a Renilla luciferase reporter gene (Env.IMC.LucR viruses). This global panel should facilitate highly standardized assessments of vaccine-elicited neutralizing antibodies across multiple HIV-1 vaccine platforms in different parts of the world. IMPORTANCE An effective HIV-1 vaccine will need to overcome the extraordinary genetic variability of the virus, where most variation occurs in the viral envelope glycoproteins that are the sole targets for neutralizing antibodies. Efforts to elicit broadly cross-reactive neutralizing antibodies that will protect against infection by most circulating strains of the virus are guided in part by in vitro assays that determine the ability of vaccine-elicited antibodies to neutralize genetically diverse HIV-1 variants. Until now, little information was available on how many and which strains of the virus are best suited for this purpose. We applied robust statistical methods to evaluate a large neutralization data set and identified a small panel of viruses that are a good representation of the global epidemic. The neutralization properties of this new panel of reference strains should facilitate the development of an effective HIV-1 vaccine. PMID:24352443
deCamp, Allan; Hraber, Peter; Bailer, Robert T; Seaman, Michael S; Ochsenbauer, Christina; Kappes, John; Gottardo, Raphael; Edlefsen, Paul; Self, Steve; Tang, Haili; Greene, Kelli; Gao, Hongmei; Daniell, Xiaoju; Sarzotti-Kelsoe, Marcella; Gorny, Miroslaw K; Zolla-Pazner, Susan; LaBranche, Celia C; Mascola, John R; Korber, Bette T; Montefiori, David C
2014-03-01
Standardized assessments of HIV-1 vaccine-elicited neutralizing antibody responses are complicated by the genetic and antigenic variability of the viral envelope glycoproteins (Envs). To address these issues, suitable reference strains are needed that are representative of the global epidemic. Several panels have been recommended previously, but no clear answers have been available on how many and which strains are best suited for this purpose. We used a statistical model selection method to identify a global panel of reference Env clones from among 219 Env-pseudotyped viruses assayed in TZM-bl cells with sera from 205 HIV-1-infected individuals. The Envs and sera were sampled globally from diverse geographic locations and represented all major genetic subtypes and circulating recombinant forms of the virus. Assays with a panel size of only nine viruses adequately represented the spectrum of HIV-1 serum neutralizing activity seen with the larger panel of 219 viruses. An optimal panel of nine viruses was selected and augmented with three additional viruses for greater genetic and antigenic coverage. The spectrum of HIV-1 serum neutralizing activity seen with the final 12-virus panel closely approximated the activity seen with subtype-matched viruses. Moreover, the final panel was highly sensitive for detection of many of the known broadly neutralizing antibodies. For broader assay applications, all 12 Env clones were converted to infectious molecular clones using a proviral backbone carrying a Renilla luciferase reporter gene (Env.IMC.LucR viruses). This global panel should facilitate highly standardized assessments of vaccine-elicited neutralizing antibodies across multiple HIV-1 vaccine platforms in different parts of the world. An effective HIV-1 vaccine will need to overcome the extraordinary genetic variability of the virus, where most variation occurs in the viral envelope glycoproteins that are the sole targets for neutralizing antibodies. Efforts to elicit broadly cross-reactive neutralizing antibodies that will protect against infection by most circulating strains of the virus are guided in part by in vitro assays that determine the ability of vaccine-elicited antibodies to neutralize genetically diverse HIV-1 variants. Until now, little information was available on how many and which strains of the virus are best suited for this purpose. We applied robust statistical methods to evaluate a large neutralization data set and identified a small panel of viruses that are a good representation of the global epidemic. The neutralization properties of this new panel of reference strains should facilitate the development of an effective HIV-1 vaccine.
Ma, Guangcai; Yuan, Quan; Yu, Haiying; Lin, Hongjun; Chen, Jianrong; Hong, Huachang
2017-04-01
The binding of organic chemicals to serum albumin can significantly reduce their unbound concentration in blood and affect their biological reactions. In this study, we developed a new QSAR model for bovine serum albumin (BSA) - water partition coefficients (K BSA/W ) of neutral organic chemicals with large structural variance, logK BSA/W values covering 3.5 orders of magnitude (1.19-4.76). All chemical geometries were optimized by semi-empirical PM6 algorithm. Several quantum chemical parameters that reflect various intermolecular interactions as well as hydrophobicity were selected to develop QSAR model. The result indicates the regression model derived from logK ow , the most positive net atomic charges on an atom, Connolly solvent excluded volume, polarizability, and Abraham acidity could explain the partitioning mechanism of organic chemicals between BSA and water. The simulated external validation and cross validation verifies the developed model has good statistical robustness and predictive ability, thus can be used to estimate the logK BSA/W values for chemicals in application domain, accordingly to provide basic data for the toxicity assessment of the chemicals. Copyright © 2016 Elsevier Inc. All rights reserved.
Gazarian, Karlen G; Palacios-Rodríguez, Yadira; Gazarian, Tatiana G; Huerta, Leonor
2013-06-01
The crown region of the V3 loop in HIV-1 that contains the conserved amino acid sequence GPGR/G is known as the principal neutralizing determinant due to the extraordinary ability of antibodies to this region to neutralize the virus. To complement the existing peptide models of this epitope, we describe a family of 18 phage-displayed peptides, which include linear 12mer and constrained 7mer peptides that was selected by screening random libraries with serum from HIV-1 subtype B-infected patients. The 7mer constrained peptides presented two conserved amino acid sequences: PR-L in N-terminus and GPG in the C-terminus. On the basis of these peptides we propose a mimotope model of the V3 crown epitope in which the PR-L and GPG sequences represent the two known epitope binding sites. The GPG, has the same function as the V3 crown GPGR sequence but without the involvement of the "R" despite its being considered as the signature of the epitope in B-subtype viruses. The PR-L contains a proline not existing in the epitope that is postulated to induce kinks in the backbones of all peptides and create a spatial element mimicking the N-terminal conformationally variable binding site. Rabbit serum to these mimotopes recognized the V3 peptides and moderately decreased the fusion between HIV-1 Env- and CD4-expressing Jurkat cells. This study proposes the efficient generation by means of patient sera of V3 epitope mimics validated by interaction with the antibodies to contemporary viruses induced in patients. The serum antibody-selectable mimotopes are sources of novel information on the fine structure-function properties of HIV-1 principal neutralizing domain and candidate anti-HIV-1 immunogens. Copyright © 2012 Elsevier Ltd. All rights reserved.
Huang, Zhen-Yu; Gallagher, John R.; Lin, Yixin; Lou, Huan; Whitbeck, J. Charles; Wald, Anna; Cohen, Gary H.; Eisenberg, Roselyn J.
2015-01-01
ABSTRACT Herpes simplex virus 1 (HSV-1) and HSV-2 infect many humans and establish a latent infection in sensory ganglia. Although some infected people suffer periodic recurrences, others do not. Infected people mount both cell-mediated and humoral responses, including the production of virus-neutralizing antibodies (Abs) directed at viral entry glycoproteins. Previously, we examined IgGs from 10 HSV-seropositive individuals; all neutralized virus and were directed primarily against gD or gD+gB. Here, we expand our studies and examine 32 additional sera from HSV-infected individuals, 23 of whom had no recurrent disease. Using an Octet RED96 system, we screened all 32 serum samples directly for both glycoprotein binding and competition with known neutralizing anti-gD and -gB monoclonal Abs (MAbs). On average, the recurrent cohort exhibited higher binding to gD and gB and had higher neutralization titers. There were similar trends in the blocking of MAbs to critical gD and gB epitopes. When we depleted six sera of Abs to specific glycoproteins, we found different types of responses, but always directed primarily at gD and/or gB. Interestingly, in one dual-infected person, the neutralizing response to HSV-2 was due to gD2 and gB2, whereas HSV-1 neutralization was due to gD1 and gB1. In another case, virus neutralization was HSV-1 specific, with the Ab response directed entirely at gB1, despite this serum blocking type-common anti-gD and -gB neutralizing MAbs. These data are pertinent in the design of future HSV vaccines since they demonstrate the importance of both serotypes of gD and gB as immunogens. IMPORTANCE We previously showed that people infected with HSV produce neutralizing Abs directed against gD or a combination of gD+gB (and in one case, gD+gB+gC, which was HSV-1 specific). In this more extensive study, we again found that gD or gD+gB can account for the virus neutralizing response and critical epitopes of one or both of these proteins are represented in sera of naturally infected humans. However, we also found that some individuals produced a strong response against gB alone. In addition, we identified type-specific contributions to HSV neutralization from both gD and gB. Contributions from the other entry glycoproteins, gC and gH/gL, were minimal and limited to HSV-1 neutralization. Knowing the variations in how humans see and mount a response to HSV will be important to vaccine development. PMID:26109729
Canine distemper epizootic in lions, tigers, and leopards in North America.
Appel, M J; Yates, R A; Foley, G L; Bernstein, J J; Santinelli, S; Spelman, L H; Miller, L D; Arp, L H; Anderson, M; Barr, M
1994-07-01
Canine distemper virus (CDV) infection occurred in captive leopards (Panthera pardus), tigers (Panthera tigris), lions (Panthera leo), and a jaguar (Panthera onca) in 1991 and 1992. An epizootic affected all 4 types of cats at the Wildlife Waystation, San Fernando, California, with 17 mortalities. CDV-infected raccoons were thought to be the source of infection in these cats. Two black leopards died at the Naibi Zoo, Coal Valley, Illinois, and 2 tigers died at the Shambala Preserve, Acton, California. Initial clinical signs were anorexia with gastrointestinal and/or respiratory disease followed by seizures. Canine distemper virus was isolated from 3 leopards, 3 tigers, and 3 lions that died or were euthanized when moribund. Monoclonal antibody testing identified the virus isolates as CDV. Gross and histopathologic findings were similar to those found in canids with distemper with a few exceptions. There were fewer lesions in the brain, and there was a pronounced type 2 cell proliferation in the lung, with inclusion bodies and CDV antigen demonstrated by immunohistology. Neutralizing antibody to CDV was found in high titers in serum from most animals but was absent or was found only in low titers in some cats that succumbed after CDV infection. There was a marked difference in neutralizing antibody titers when tests were done with different strains of CDV.
Kasaian, Marion T; Tan, Xiang-Yang; Jin, Macy; Fitz, Lori; Marquette, Kimberly; Wood, Nancy; Cook, Timothy A; Lee, Julie; Widom, Angela; Agostinelli, Rita; Bree, Andrea; Schlerman, Franklin J; Olland, Stephane; Wadanoli, Michael; Sypek, Joseph; Gill, Davinder; Goldman, Samuel J; Tchistiakova, Lioudmila
2008-06-01
Interleukin (IL)-13 is a key cytokine driving allergic and asthmatic responses and contributes to airway inflammation in cynomolgus monkeys after segmental challenge with Ascaris suum antigen. IL-13 bioactivity is mediated by a heterodimeric receptor (IL-13Ralpha1/IL-4Ralpha) and can be inhibited in vitro by targeting IL-13 interaction with either chain. However, in cytokine systems, in vitro neutralization activity may not always predict inhibitory function in vivo. To address the efficacy of two different IL-13 neutralization mechanisms in a primate model of atopic disease, two humanized monoclonal antibodies to IL-13 were generated, with highly homologous properties, differing in epitope recognition. Ab01 blocks IL-13 interaction with IL-4Ralpha, and Ab02 blocks IL-13 interaction with IL-13Ralpha1. In a cynomolgus monkey model of IgE responses to A. suum antigen, both Ab01 and Ab02 effectively reduced serum titers of Ascaris-specific IgE and diminished ex vivo Ascaris-triggered basophil histamine release, assayed 8 weeks after a single administration of antibody. The two antibodies also produced comparable reductions in pulmonary inflammation after lung segmental challenge with Ascaris antigen. Increased serum levels of IL-13, lacking demonstrable biological activity, were seen postchallenge in animals given either anti-IL-13 antibody but not in control animals given human IgG of irrelevant specificity. These findings demonstrate a potent effect of IL-13 neutralization on IgE-mediated atopic responses in a primate system and show that IL-13 can be efficiently neutralized by targeting either the IL-4Ralpha-binding epitope or the IL-13Ralpha1-binding epitope.
Cross neutralization of coral snake venoms by commercial Australian snake antivenoms.
Ramos, Henrique Roman; Vassão, Ruth Camargo; de Roodt, Adolfo Rafael; Santos E Silva, Ed Carlos; Mirtschin, Peter; Ho, Paulo Lee; Spencer, Patrick Jack
2017-01-01
Although rare, coral snake envenomation is a serious health threat in Brazil, because of the highly neurotoxic venom and the scarcely available antivenom. The major bottleneck for antivenom production is the low availability of venom. Furthermore, the available serum is not effective against all coral snake species found in Brazil. An alternative to circumvent the lack of venom for serum production and the restricted protection of the actually available antivenom would be of great value. We compared the Brazilian coral snake and mono and polyvalent Australian antivenoms in terms of reactivity and protection. The immunoreactivity of venoms from 9 coral snakes species were assayed by ELISA and western blot using the Brazilian Micrurus and the Australian pentavalent as well as monovalent anti-Notechis, Oxyuranus and Pseudechis antivenoms. Neutralization assays were performed in mice, using 3 LD 50 of the venoms, incubated for 30 minutes with 100 μL of antivenom/animal. All the venoms reacted against the autologous and heterologous antivenoms. Nevertheless, the neutralization assays showed that the coral snake antivenom was only effective against M. corallinus, M. frontalis, M. fulvius, M. nigrocinctus and M. pyrrhocryptus venoms. On the other hand, the Australian pentavalent antivenom neutralized all venoms except the one from M. spixii. A combination of anti-Oxyuranus and Pseudechis monovalent sera, extended the protection to M. altirostris and, partially, to M. ibiboboca. By adding Notechis antivenom to this mixture, we obtained full protection against M. ibiboboca and partial neutralization against M. lemniscatus venoms. Our findings confirm the limited effectiveness of the Brazilian coral snake antivenom and indicate that antivenoms made from Australian snakes venoms are an effective alternative for coral snake bites in South America and also in the United States were coral snake antivenom production has been discontinued.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Saunders, G.C. Clinard, E.H.; Bartlett, M.L.; Sanders, W.M.
1976-01-01
The rapid, indirect enzyme-labeled antibody (ELA) microplate test has been developed as a diagnostic and surveillance tool to aid in the control of animal disease. Data are presented, which illustrate the application of the test to viral (hog cholera), parasitic (trichinosis), and bacterial (brucellosis) diseases of animals. A greater than 95 percent correlation was observed between the hog cholera ELA test and the hog cholera serum neutralization test performed on over 2000 mixed hog cholera positive and negative field samples obtained during the 1976 New Jersey epizootic. Of 56 swine naturally infected with Trichinella spiralis at a level considered dangerousmore » to man, all were ELA positive, while only one of 360 T. spiralis negative packing house sera was ELA positive. Preliminary experiments with bovine brucellosis (Brucella abortus) indicate that the ELA test is more sensitive than other test methods currently in use. ELA procedures should soon become tests of choice for the detection of antibodies to animal disease agents.« less
Tesfay, Mulu Z.; Kirk, Amber C.; Hadac, Elizabeth M.; Griesmann, Guy E.; Federspiel, Mark J.; Barber, Glen N.; Henry, Stephen M.; Peng, Kah-Whye
2013-01-01
We are developing oncolytic vesicular stomatitis viruses (VSVs) for systemic treatment of multiple myeloma, an incurable malignancy of antibody-secreting plasma cells that are specifically localized in the bone marrow. One of the presumed advantages for using VSV as an oncolytic virus is that human infections are rare and preexisting anti-VSV immunity is typically lacking in cancer patients, which is very important for clinical success. However, our studies show that nonimmune human and mouse serum can neutralize clinical-grade VSV, reducing the titer by up to 4 log units in 60 min. In addition, we show that neutralizing anti-VSV antibodies negate the antitumor efficacy of VSV, a concern for repeat VSV administration. We have investigated the potential use of covalent modification of VSV with polyethylene glycol (PEG) or a function-spacer-lipid (FSL)–PEG construct to inhibit serum neutralization and to limit hepatosplenic sequestration of systemically delivered VSV. We report that in mice passively immunized with neutralizing anti-VSV antibodies, PEGylation of VSV improved the persistence of VSV in the blood circulation, maintaining a more than 1-log-unit increase in VSV genome copies for up to 1 h compared to the genome copy numbers for the non-PEGylated virus, which was mostly cleared within 10 min after intravenous injection. We are currently investigating if this increase in PEGylated VSV circulating half-life can translate to increased virus delivery and better efficacy in mouse models of multiple myeloma. PMID:23325695
Karlberg, Helen; Sharifi-Mood, Batool; Mousavi-Jazi, Mehrdad; Dilcher, Meik; Lindegren, Gunnel; Mardani, Masoud; Bereskly, Sandor; Weidmann, Manfred; Mirazimi, Ali
2015-04-01
Crimean-Congo hemorrhagic fever (CCHF) is an arthropod-borne disease of humans associated with a severe clinical picture, including hemorrhagic syndrome and a high mortality rate. CCHF virus is widely distributed throughout large areas of the world. To characterize the serological status in CCHF patients, paired clinical samples were collected from suspected CCHF patients and analyzed by microbiological and other laboratory analyses with the aim of: determining the presence of neutralizing antibodies against CCHF virus; investigating the cross-reactivity of these neutralizing antibodies against virus isolated from the same outbreak and against other available laboratory strain; and studying the relationship between the isolated virus with other virus by whole genome sequencing. Patients at Boo-Ali Hospital, Zahedan, Iran, with clinical symptoms ranging from mild to severe hemorrhagic fever were included in the study. Two serum samples were taken from each patient, the first as soon as the patient matched the criteria for CCHF notification and the second when the patient was discharged from hospital (2 weeks later). Commercial and in-house assays revealed a positive IgM signal in acute serum samples from six patients. A novel finding was that CCHF patients develop neutralizing antibodies soon after infection. Interestingly these antibodies were able to neutralize other CCHF virus strains too. The complete sequence of the Zahedan 2007 isolate, including the hitherto unknown first L-segment sequence, was identified using an original clinical sample from one patient with confirmed CCHF infection. © 2015 Wiley Periodicals, Inc.
Qiu, Chao; Huang, Yang; Wang, Qian; Tian, Di; Zhang, Wanju; Hu, Yunwen; Yuan, Zhenghong; Zhang, Xiaoyan; Xu, Jianqing
2012-01-01
A mass vaccination has been implemented to prevent the spread of 2009 pandemic influenza virus in China. Highly limited information is available on whether this vaccine induces cross-reactive neutralization antibodies against other subtypes of influenza viruses. We employed pseudovirus-based assays to analyze heterosubtypic neutralization responses in serum samples of 23 recipients of 2009 pandemic influenza vaccine. One dose of pandemic vaccine not only stimulated good neutralization antibodies against cognate influenza virus 2009 influenza A (H1N1), but also raised broad cross-reactive neutralization activities against seasonal H3N2 and highly pathogenic avian influenza virus H5N1 and lesser to H2N2. The cross-reactive neutralization activities were completely abolished after the removal of immunoglobin G (IgG). In contrast, H1N1 vaccination alone in influenza-naive mice elicited only vigorous homologous neutralizing activities but not cross-reactive neutralization activities. Our data suggest that the cross-reactive neutralization epitopes do exist in this vaccine and could elicit significant cross-reactive neutralizing IgG antibodies in the presence of preexisting responses. The exposure to H1N1 vaccine is likely to modify the hierarchical order of preexisting immune responses to influenza viruses. These findings provide insights into the evolution of human immunity to influenza viruses after experiencing multiple influenza virus infections and vaccinations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Qibin; Petyuk, Vladislav A.; Schepmoes, Athena A.
Non-enzymatic glycation of tissue proteins has important implications in the development of complications of diabetes mellitus. While electron transfer dissociation (ETD) has been shown to outperform collision-induced dissociation (CID) in sequencing glycated peptides by tandem mass spectrometry, ETD instrumentation is not yet available in all laboratories. In this study, we evaluated different advanced CID techniques (i.e., neutral-loss triggered MS3 and multi-stage activation) during LC-MSn analyses of Amadori-modified peptides enriched from human serum glycated in vitro. During neutral-loss triggered MS3 experiments, MS3 scans triggered by neutral-losses of 3 H2O or 3 H2O + HCHO produced similar results in terms of glycatedmore » peptide identifications. However, neutral losses of 3 H2O resulted in significantly more glycated peptide identifications during multi-stage activation experiments. Overall, the multi-stage activation approach produced more glycated peptide identifications, while the neutral-loss triggered MS3 approach resulted in much higher specificity. Both techniques offer a viable alternative to ETD for identifying glycated peptides when that method is unavailable.« less
Wang, Fang; Zhang, Ming; Xie, Bing-Feng; Cao, Han; Tong, Shao-Yong; Wang, Jun-Rong; Yu, Xiao-Ping; Tang, Yang; Yang, Jing-Ran; Sun, Ming-Bo
2013-04-01
To study the effect of aluminume adjuvant and immunization schedule on immunogenicity of Sabin inactivated poliovirus vaccine. Four batches of Sabin IPV were produced by different concentrations of type 1, 2, and 3 poliovirus and administrated on three-dose schedule at 0, 1, 2 months and 0, 2, 4 months on rats. Serum samples were collected one month after each dose and neutralizing antibody titers against three types poliovirus were determined by micro-neutralization assay. The GMTs of neutralizing antibodies against three types poliovirus increased significantly and the seropositivity rates were 100% in all groups after 3 doses. There was no significant difference between two immunization schedules, and the 0, 2, 4 month schedule could induce higher level neutralizing antibody compared to the 0, 1, 2 month schedule. The groups with aluminum adjuvant could induce higher level neutralizing antibody compared to the groups without adjuvant. Aluminum djuvant and immunization schedule could improve the immunogenicity of Sabin IPV.
Selected HIV-1 Env trimeric formulations act as potent immunogens in a rabbit vaccination model.
Heyndrickx, Leo; Stewart-Jones, Guillaume; Jansson, Marianne; Schuitemaker, Hanneke; Bowles, Emma; Buonaguro, Luigi; Grevstad, Berit; Vinner, Lasse; Vereecken, Katleen; Parker, Joe; Ramaswamy, Meghna; Biswas, Priscilla; Vanham, Guido; Scarlatti, Gabriella; Fomsgaard, Anders
2013-01-01
Ten to 30% of HIV-1 infected subjects develop broadly neutralizing antibodies (bNAbs) during chronic infection. We hypothesized that immunizing rabbits with viral envelope glycoproteins (Envs) from these patients may induce bNAbs, when formulated as a trimeric protein and in the presence of an adjuvant. Based on in vitro neutralizing activity in serum, patients with bNAbs were selected for cloning of their HIV-1 Env. Seven stable soluble trimeric gp140 proteins were generated from sequences derived from four adults and two children infected with either clade A or B HIV-1. From one of the clade A Envs both the monomeric and trimeric Env were produced for comparison. Rabbits were immunized with soluble gp120 or trimeric gp140 proteins in combination with the adjuvant dimethyl dioctadecyl ammonium/trehalose dibehenate (CAF01). Env binding in rabbit immune serum was determined using ELISAs based on gp120-IIIB protein. Neutralizing activity of IgG purified from rabbit immune sera was measured with the pseudovirus-TZMbl assay and a PBMC-based neutralization assay for selected experiments. It was initially established that gp140 trimers induce better antibody responses over gp120 monomers and that the adjuvant CAF01 was necessary for such strong responses. Gp140 trimers, based on HIV-1 variants from patients with bNAbs, were able to elicit both gp120IIIB specific IgG and NAbs to Tier 1 viruses of different subtypes. Potency of NAbs closely correlated with titers, and an gp120-binding IgG titer above a threshold of 100,000 was predictive of neutralization capability. Finally, peptide inhibition experiments showed that a large fraction of the neutralizing IgG was directed against the gp120 V3 region. Our results indicate that the strategy of reverse immunology based on selected Env sequences is promising when immunogens are delivered as stabilized trimers in CAF01 adjuvant and that the rabbit is a valuable model for HIV vaccine studies.
Saladino, R A; Stack, A M; Thompson, C; Sattler, F; Novitsky, T J; Siber, G R; Fleisher, G R
1996-07-01
To assess the benefit of a recombinant endotoxin neutralizing protein from Limulus polyphemus in treating Gram-negative bacterial sepsis in rabbits. Prospective, blinded, controlled, laboratory trial. Animal research laboratory. New Zealand White rabbits. We established a rabbit model of Escherichia coli peritonitis and bacteremia, with high mortality rate, despite treatment with gentamicin and ceftriaxone. Twenty-five pairs of male New Zealand White rabbits were challenged intraperitoneally with E. coli O18ac K1 in 5% porcine mucin (mean 7 x 10(1) colony-forming units). All animals were treated with intravenous gentamicin (2.5 mg/kg) and ceftriaxone (100 mg/kg), and with either intravenous endotoxin neutralizing protein (50 mg/kg) or saline 1 hr after E. coli challenge. All animals were bacteremic 1 hr after challenge (mean 3.6 x 10(5) colony-forming units/mL). Animals in both groups developed tachycardia, hypotension, and acidosis (NS). Geometric mean serum endotoxin and tumor necrosis factor (TNF) concentrations were significantly ( p < .001) higher 1 hr after challenge compared with baseline prechallenge concentrations in both groups. From 1 to 2 hrs after challenge, endotoxin concentrations increased 2.5-fold in control animals (95% confidence interval = 13.1 to 32.9 endotoxin units/mL, p = .024), whereas endotoxin concentrations increased only 1.2-fold in endotoxin neutralizing protein-treated animals (95% confidence interval = 20.4 to 23.6 endotoxin units/mL, NS). TNF concentrations increased significantly (p < .001) in both groups from 1 to 2 hrs after challenge. Eighteen (72%) of 25 endotoxin neutralizing protein-treated animals vs. 11 (44%) of 25 controls survived 24 hrs (p = .032). Treatment with endotoxin neutralizing protein had the following effects: a) the increase in serum endotoxin was blunted, but not TNF concentrations measured 1 hr after antibiotic treatment; and b) survival in rabbits with E. Coli sepsis was improved.
Experimental infection of pregnant goats with swine fever virus.
Shimizu, M; Kumagai, T
1989-07-01
Thirteen pregnant goats were inoculated intravenously with the ALD strain of virulent swine fever (SF) virus on Days 64-84 of gestation. Dams showed transient and mild viremia, and produced high serum neutralizing (SN) antibody after inoculation. Six inoculated dams were reared until parturition occurred and bore six apparently normal, one apparently normal but dead, one mummified and three edematous kids. Neutralizing antibody was demonstrated in the pre-colostral sera obtained from all normal kids, but no SF virus was isolated from any of them. The other seven dams were killed on post-inoculation days (PID) 5-61, and fetuses, placenta and amnion were tested for the virus and SN antibody. All fetuses of five dams examined within PID 40 were positive for SF virus, but negative for SN antibody. SF virus was also isolated from one of three fetuses examined on PID 61. Conversely, the other two fetuses examined on PID 61 were negative for SF virus, but positive for SN antibody. Furthermore, SF virus was isolated from the placenta and amnion of all the dams.
Ackermann-Gäumann, Rahel; Tritten, Marie-Lise; Hassan, Mona; Lienhard, Reto
2018-05-01
Tick-borne encephalitis (TBE) is endemic in many parts of Europe and Asia. The diagnosis of this disease is essentially based on the demonstration of specific antibodies. For reasons of simplicity, automatization and quick availability of test results, enzyme-linked immunosorbent assays (ELISAs) are the method of choice for serological diagnosis of TBE. Here, we evaluated three commercially available anti-TBEV IgG and IgM ELISAs using 251 serum samples: the SERION ELISA classic FSME Virus/TBE Virus IgG and IgM kit (Virion\\Serion), the RIDASCREEN ® FSME/TBE IgG and IgM kit (R-Biopharm), and the anti-FSME/TBE virus ELISA "Vienna" IgG/anti-FSME/TBE virus ELISA IgM kit (Euroimmun). In total, discrepant test results for IgG and/or IgM were observed for 37/251 (14.7 %) of tested samples; differences were statistically significant. Reference values defined by serum neutralization test (SNT, n = 25) or results provided by EQA organizers (n = 2) were established for a subset of samples. In relation to these values, false-positive results were observed mainly for Euroimmun Vienna IgG and RIDASCREEN IgG, whereas false-negative results were primarily observed for Virion\\Serion IgG and RIDASCREEN IgM kits. In routine diagnostics, specificity problems are of major relevance and may be addressed by analyzing the respective samples using SNT. Copyright © 2018 Elsevier GmbH. All rights reserved.
Lambert, Stacie L; Aslam, Shahin; Stillman, Elizabeth; MacPhail, Mia; Nelson, Christine; Ro, Bodrey; Sweetwood, Rosemary; Lei, Yuk Man; Woo, Jennifer C; Tang, Roderick S
2015-01-01
Illness associated with Respiratory Syncytial Virus (RSV) remains an unmet medical need in both full-term infants and older adults. The fusion glycoprotein (F) of RSV, which plays a key role in RSV infection and is a target of neutralizing antibodies, is an attractive vaccine target for inducing RSV-specific immunity. BALB/c mice and cotton rats, two well-characterized rodent models of RSV infection, were used to evaluate the immunogenicity of intramuscularly administered RSV vaccine candidates consisting of purified soluble F (sF) protein formulated with TLR4 agonist glucopyranosyl lipid A (GLA), stable emulsion (SE), GLA-SE, or alum adjuvants. Protection from RSV challenge, serum RSV neutralizing responses, and anti-F IgG responses were induced by all of the tested adjuvanted RSV sF vaccine formulations. However, only RSV sF + GLA-SE induced robust F-specific TH1-biased humoral and cellular responses. In mice, these F-specific cellular responses include both CD4 and CD8 T cells, with F-specific polyfunctional CD8 T cells that traffic to the mouse lung following RSV challenge. This RSV sF + GLA-SE vaccine formulation can also induce robust RSV neutralizing titers and prime IFNγ-producing T cell responses in Sprague Dawley rats. These studies indicate that a protein subunit vaccine consisting of RSV sF + GLA-SE can induce robust neutralizing antibody and T cell responses to RSV, enhancing viral clearance via a TH1 immune-mediated mechanism. This vaccine may benefit older populations at risk for RSV disease.
Oscherwitz, Jon; Feldman, Daniel; Yu, Fen; Cease, Kemp B
2015-01-09
Anthrax represents a formidable bioterrorism threat for which new, optimized vaccines are required. We previously demonstrated that epitope-focused multiple antigenic peptides or a recombinant protein in Freund's adjuvant can elicit Ab against the loop neutralizing determinant (LND), a cryptic linear neutralizing epitope in the 2ß2-2ß3 loop of protective antigen from Bacillus anthracis, which mediated protection of rabbits from inhalation challenge with B. anthracis Ames strain. However, demonstration of efficacy using human-use adjuvants is required before proceeding with further development of an LND vaccine for testing in non-human primates and humans. To optimize the LND immunogen, we first evaluated the protective efficacy and immune correlates associated with immunization of rabbits with mixtures containing two molecular variants of multiple antigenic peptides in Freunds adjuvant, termed BT-LND(2) and TB-LND(2). TB-LND(2) was then further evaluated for protective efficacy in rabbits employing human-use adjuvants. Immunization of rabbits with TB-LND(2) in human-use adjuvants elicited protection from Ames strain spore challenge which was statistically indistinguishable from that elicited through immunization with protective antigen. All TB-LND(2) rabbits with any detectable serum neutralization prior to challenge were protected from aerosolized spore exposure. Remarkably, rabbits immunized with TB-LND(2) in Alhydrogel/CpG had significant anamnestic increases in post-challenge LND-specific Ab and neutralization titers despite little evidence of spore germination in these rabbits. An LND-specific epitope-focused vaccine may complement PA-based vaccines and may represent a complementary stand-alone vaccine for anthrax. Copyright © 2014 Elsevier Ltd. All rights reserved.
Jiménez-Vargas, J M; Quintero-Hernández, V; González-Morales, L; Ortiz, E; Possani, L D
2017-03-15
This manuscript describes the design of plasmids containing the genes coding for four main mammalian toxins of scorpions from the genus Centruroides (C.) of Mexico. The genes that code for toxin 2 of C. noxius (Cn2), toxin 2 from C. suffusus (Css2) and toxins 1 and 2 from C. limpidus (Cll1 and Cll2) were included into individual plasmids carrying the genetic construction for expression of fusion proteins containing a leader peptide (pelB) that directs the expressed protein to the bacterial periplasm, a carrier protein (thioredoxin), the cleavage site for enterokinase, the chosen toxin and a poly-histidine tag (6xHis-tag) for purification of the hybrid protein by immobilized metal ion affinity chromatography after expression in Escherichia coli strain BL21 (DE3). The purified hybrid proteins containing the recombinant toxins (abbreviated Thio-EK-Toxin) were used for immunization of three independent groups of ten mice and four rabbits. Challenging the first group of mice, immunized with recombinant Thio-EK-Css2, with three median lethal doses (LD 50 ) of C. suffusus soluble venom resulted in the survival of all the test animals without showing intoxication symptoms. All control mice (none immunized) died. Similar results were obtained with mice previously immunized with Thio-EK-Cn2 and challenged with C. noxius venom. The third group of mice immunized with both Thio-EK-Cll1 and Thio-EK-Cll2 showed an 80% survival ratio when challenged with only one LD 50 of C. limpidus venom, all showing symptoms of intoxication. The sera from rabbits immunized with a combination of the four recombinant toxins were collected separately and used to assess their neutralization capacity in vitro (pre-incubating the serum with the respective scorpion venom and injecting the mixture into mice), using six mice for each serum/venom combination tested. The venoms from the six most dangerous scorpion species of Mexico were assayed: C. noxius, C. suffusus, C. limpidus, C. elegans, C. tecomanus and C. sculpturatus. Two hundred and 50 μL of serum from any of the immunized rabbits were enough to neutralize three LD 50 of any of the tested venoms, with mice showing no symptoms of intoxication. These results confirm that the recombinant forms of the main toxins from the most dangerous scorpions of Mexico are excellent immunogens for the production of antivenoms to treat scorpion intoxications. Copyright © 2017 Elsevier Ltd. All rights reserved.
Bleau, A M; Levitchi, M C; Maurice, H; du Souich, P
2000-08-01
Serum from humans with an acute upper respiratory viral infection and from rabbits with turpentine-induced inflammation reduce the catalytic activity of hepatic cytochrome P450 (P450). The aim of this study was to identify the serum mediators responsible for the decrease in P450 activity. Rabbit and human sera were fractionated by size exclusion chromatography and the fractions tested for their ability to reduce the activity and amount of P450 after 4 h of incubation with hepatocytes from turpentine-treated rabbits (H(INF)). Rabbit and human sera decreased P450 activity by around 40% without any change in the amount of CYP1A1 and 1A2 apoproteins. In rabbit serum, the fraction containing proteins of M(r) 23-15 kDa decreased P450 content by 41%, but did not alter the amount of the apoproteins. Anti-IL-6 antibody added to the M(r) 23-15 kDa fraction restored P450 content to 97% of control values, while anti-IL-1beta, TNF-alpha and IFN-gamma antibodies had no effect. Supporting the role of IL-6, incubation of H(INF) in the presence of IL-6 for 4 h reduced P450 content by 40%. In human serum, the fraction containing proteins of M(r) >95 kDa lowered P450 content by 43% without modifying the amounts of CYP1A1/2. Neutralization experiments showed that IFN-gamma, IL-6, and IL-1beta contributed to the decrease in P450 content. In conclusion, the present results demonstrate that IL-6, and IFN-gamma, IL-6 and IL-1beta are the serum mediators released in vivo by a turpentine-induced inflammatory reaction in the rabbit and an upper respiratory viral infection in humans, respectively, inactivating hepatic P450.
Bleau, Anne-Marie; Levitchi, Mihaela C; Maurice, Hélène; du Souich, Patrick
2000-01-01
Serum from humans with an acute upper respiratory viral infection and from rabbits with turpentine-induced inflammation reduce the catalytic activity of hepatic cytochrome P450 (P450). The aim of this study was to identify the serum mediators responsible for the decrease in P450 activity.Rabbit and human sera were fractionated by size exclusion chromatography and the fractions tested for their ability to reduce the activity and amount of P450 after 4 h of incubation with hepatocytes from turpentine-treated rabbits (HINF). Rabbit and human sera decreased P450 activity by around 40% without any change in the amount of CYP1A1 and 1A2 apoproteins.In rabbit serum, the fraction containing proteins of Mr 23–15 kDa decreased P450 content by 41%, but did not alter the amount of the apoproteins. Anti-IL-6 antibody added to the Mr 23–15 kDa fraction restored P450 content to 97% of control values, while anti-IL-1β, TNF-α and IFN-γ antibodies had no effect. Supporting the role of IL-6, incubation of HINF in the presence of IL-6 for 4 h reduced P450 content by 40%.In human serum, the fraction containing proteins of Mr >95 kDa lowered P450 content by 43% without modifying the amounts of CYP1A1/2. Neutralization experiments showed that IFN-γ, IL-6, and IL-1β contributed to the decrease in P450 content.In conclusion, the present results demonstrate that IL-6, and IFN-γ, IL-6 and IL-1β are the serum mediators released in vivo by a turpentine-induced inflammatory reaction in the rabbit and an upper respiratory viral infection in humans, respectively, inactivating hepatic P450. PMID:10952665
Antibody neutralization of retargeted measles viruses
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
Souza, A M; Reis, J K P; Assis, R A; Horta, C C; Siqueira, F F; Facchin, S; Alvarenga, E R; Castro, C S; Salvarani, F M; Silva, R O S; Pires, P S; Contigli, C; Lobato, F C F; Kalapothakis, E
2010-02-18
Epsilon toxin produced by Clostridium perfringens types B and D causes enterotoxemia in sheep, goats and calves. Enterotoxemia can cause acute or superacute disease, with sudden death of the affected animal. It provokes huge economic losses when large numbers of livestock are affected. Therapeutic intervention is challenging, because the disease progresses very rapidly. However, it can be prevented by immunization with specific immunogenic vaccines. We cloned the etx gene, encoding epsilon toxin, into vector pET-11a; recombinant epsilon toxin (rec-epsilon) was expressed in inclusion bodies and was used for animal immunization. Serum protection was evaluated and cross-serum neutralization tests were used to characterize the recombinant toxin. To analyze the potency of the toxin (as an antigen), rabbits were immunized with 50, 100 or 200 microg recombinant toxin, using aluminum hydroxide gel as an adjuvant. Titers of 10, 30 and 40 IU/mL were obtained, respectively. These titers were higher than the minimum level required by the European Pharmacopoeia (5 IU/mL) and by the USA Code of Federal Regulation (2 IU/mL). This rec-epsilon is a good candidate for vaccine production against enterotoxemia caused by epsilon toxin of C. perfringens type D.
Yu, Karl O. A.; Randolph, Adrienne G.; Agan, Anna A.; Yip, Wai-Ki; Truemper, Edward J.; Weiss, Scott L.; Ackerman, Kate G.; Schwarz, Adam J.; Giuliano, John S.; Hall, Mark W.; Bubeck Wardenburg, Juliane
2016-01-01
Background. Development of methicillin-resistant Staphylococcus aureus (MRSA) pneumonia after a respiratory viral infection is frequently fatal in children. In mice, S. aureus α-toxin directly injures pneumocytes and increases mortality, whereas α-toxin blockade mitigates disease. The role of α-toxin in pediatric staphylococcal-viral coinfection is unclear. Methods. We enrolled children across 34 North American pediatric intensive care units with acute respiratory failure and suspected influenza virus infection. Serial serum anti-α-toxin antibody titers and functional α-toxin neutralization capacity were compared across children coinfected with MRSA or methicillin-susceptible S. aureus (MSSA) and control children infected with influenza virus only. MRSA isolates were tested for α-toxin production and lethality in a murine pneumonia model. Results. Influenza virus was identified in 22 of 25 children with MRSA coinfection (9 died) and 22 patients with MSSA coinfection (all survived). Initial α-toxin–specific antibody titers were similar, compared with those in the 13 controls. In patients with serial samples, only MRSA-coinfected patients showed time-dependent increases in anti-α-toxin titer and functional neutralization capacity. MRSA α-toxin production from patient isolates correlated with initial serologic titers and with mortality in murine pneumonia. Conclusions. These data implicate α-toxin as a relevant antigen in severe pediatric MRSA pneumonia associated with respiratory viral infection, supporting a potential role for toxin-neutralizing therapy. PMID:27651418
Galán, Jacob A; Sánchez, Elda E; Rodríguez-Acosta, Alexis; Pérez, John C
2004-06-01
The Southern Pacific Rattlesnake (Crotalus helleri) is found in southwestern California (USA), southward through north Baja California (MX) into the northern part of southern Baja California (MX). In this study, the venoms from two Southern Pacific Rattlesnakes were characterized. The two venoms were different in color, concentration, and enzyme activities. Two commercial antivenoms neutralized both C. helleri venoms differently. Antivipmyn (Fab2H) and CroFab (FabO) neutralized both venoms but had different ED50. Four times more Fab2H antivenom was required to neutralize the C. helleri venom No. 011-084-009 than the venom from the snake No. 010-367-284. The hemorrhagic activity of two C. helleri venoms were neutralized differently by endothermic animal sera having a natural resistance to hemorrhagic activity of snake venoms. Opossums and Mexican ground squirrel sera did not neutralize the hemorrhagic activity of the venom No. 010-367-284. The sera of gray woodrats and hispid cotton rats neutralized all hemorrhagins in both C. helleri venoms. This is the first reported case in which opossum serum has not neutralized hemorrhagic activity of pit viper venom. Differences in the compositions of C. helleri venoms and their ability to be neutralized may help explain why snakebites are a difficult medical problem to treat and why effective polyvalent antivenoms are difficult to produce.
Infectivity of severe acute respiratory syndrome during its incubation period.
Zeng, Guang; Xie, Shu-Yun; Li, Qin; Ou, Jian-Ming
2009-12-01
To evaluate the infectivity of severe acute respiratory syndrome (SARS) during its incubation period by investigating chains of transmission and individuals isolated for medical observation with a view to providing scientific evidence for updating protocols of medical isolation. Individuals related with the two SARS chains of transmission in Beijing in 2003 and a group of individuals isolated for medical observation in Haidian district of Beijing during the SARS outbreak were selected as subjects of study. Contactors with SARS patients and those with symptom development following the contacts were investigated via questionnaire. Serum samples were collected from super transmitters and tested for SARS-CoV antibody by neutralization test and enzyme linked immunosorbent assay (ELISA). A total of 1112 contactors were investigated in three surveys. Of them, 669 had a history of close contact with symptomatic SARS patients, 101 developed symptoms with a rate of 15.1%, 363 had a history of close contact with patients in their incubation period, none of whom developed symptoms (0%). Serum samples were collected from 32 highly-exposed individuals, of whom 13 developing SARS symptoms after contact had serum samples positive for SARS-CoV antibody. Samples collected from the asymptomatic contactors were all negative for SARS-CoV antibody. SARS cases are infectious only during their symptomatic period and are non-infectious during the incubation period. Isolation for medical observation should be placed for individuals who are in close contact with symptomatic SARS patients. The results of our study are of decisive significance for the Ministry of Health to the definition of SARS close contactor.
Burby, Joshua W.; Lacker, Daniel
2016-01-01
Systems as diverse as the interacting species in a community, alleles at a genetic locus, and companies in a market are characterized by competition (over resources, space, capital, etc) and adaptation. Neutral theory, built around the hypothesis that individual performance is independent of group membership, has found utility across the disciplines of ecology, population genetics, and economics, both because of the success of the neutral hypothesis in predicting system properties and because deviations from these predictions provide information about the underlying dynamics. However, most tests of neutrality are weak, based on static system properties such as species-abundance distributions or the number of singletons in a sample. Time-series data provide a window onto a system’s dynamics, and should furnish tests of the neutral hypothesis that are more powerful to detect deviations from neutrality and more informative about to the type of competitive asymmetry that drives the deviation. Here, we present a neutrality test for time-series data. We apply this test to several microbial time-series and financial time-series and find that most of these systems are not neutral. Our test isolates the covariance structure of neutral competition, thus facilitating further exploration of the nature of asymmetry in the covariance structure of competitive systems. Much like neutrality tests from population genetics that use relative abundance distributions have enabled researchers to scan entire genomes for genes under selection, we anticipate our time-series test will be useful for quick significance tests of neutrality across a range of ecological, economic, and sociological systems for which time-series data are available. Future work can use our test to categorize and compare the dynamic fingerprints of particular competitive asymmetries (frequency dependence, volatility smiles, etc) to improve forecasting and management of complex adaptive systems. PMID:27689714
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.
Wilson-Rothering, Anna; Marcquenski, Susan; Koenigs, Ryan; Bruch, Ronald; Kamke, Kendall; Isermann, Daniel; Thurman, Andrew; Toohey-Kurth, Kathy
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. PMID:26135873
Parreño, Viviana; Romera, S Alejandra; Makek, Lucia; Rodriguez, Daniela; Malacari, Darío; Maidana, Silvina; Compaired, Diego; Combessies, Gustavo; Vena, María Marta; Garaicoechea, Lorena; Wigdorovitz, Andrés; Marangunich, Laura; Fernandez, Fernando
2010-10-01
Two ELISAs to quantify antibodies to BoHV-1 in the sera of cattle and immunized guinea pigs were developed and validated using ISO/IEC 17025 standards. The cut-off value of the assay was established at 20% positivity of a high positive control for screening of cattle. Using this threshold, the assay properly classified the OIE bovine reference sera EU1, EU2 and EU3. For vaccine potency testing, a cut-off of 40% was selected for both species. The reliability of the assays, given by their diagnostic sensitivity and specificity, using the threshold of 40% was 89.7% and 100%, respectively, for bovines and 94.9% and 100% for guinea pigs, respectively. There was almost perfect agreement between the ELISA and virus neutralization results. In addition, after vaccination, there was a good correlation between the neutralizing and ELISA antibody titers of the serum from the same bovine or guinea pig, sampled at 60 and 30 days post-vaccination, respectively (R(bovine)=0.88, R(guinea pig)=0.92; p<0.0001). A similar correlation was observed when analyzing the mean antibody titers of groups of vaccinated animals (R(bovine)=0.95 and R(guinea pig)=0.97; p<0.0001), indicating the relevance of the ELISAs for batch to batch vaccine potency testing in the target species and in the laboratory animal model. The intermediate precision of the assays expressed as the relative coefficient of variation (CV) of the positive control assayed over a 3-year period in the same laboratory was 22.2% for bovines and 23.1% for guinea pigs. The reproducibility of both techniques obtained in inter-laboratory assays was CV=12.4% for bovines and CV approximately 0 for guinea pigs, which met the requirements of the OIE (CV<30%). The validated ELISAs represent important methods for vaccine potency testing and for controlling BoHV-1 infections. Copyright (c) 2010 Elsevier B.V. All rights reserved.
Head-out immersion in hot water increases serum BDNF in healthy males.
Kojima, Daisuke; Nakamura, Takeshi; Banno, Motohiko; Umemoto, Yasunori; Kinoshita, Tokio; Ishida, Yuko; Tajima, Fumihiro
2017-11-20
Brain-derived neurotrophic factor (BDNF) is an important neurotrophin. The present study investigated the effects of head-out water immersion (HOI) on serum BDNF concentrations. Eight healthy men performed 20 min head-out water immersion at 42 °C (hot-HOI) and 35 °C (neutral-HOI). These experimental trials were administered in a randomised order separated by at least 7 days. Venous blood samples were withdrawn at rest, immediately after the 20-min HOI, as well as at 15 and 30 min after the end of the HOI. Serum BDNF and S100β, plasma cortisol, platelet and monocyte counts, and core body temperature (T cb ) were measured. T cb was higher at the end of the hot-HOI and 15 min after hot-HOI (p < 0.01), but recovered to pre-HOI level at 30 min after hot-HOI. No change in T cb was recorded during neutral-HOI. BDNF level was higher (p < 0.05) at the end of the hot-HOI and at 15 min after the end of hot-HOI, and returned to the baseline at 30 min after hot-HOI. S100β, platelet count and monocyte count remained stable throughout the study. Cortisol level was lower at the end of the hot-HOI and returned to pre-HOI level during the recovery period. BDNF and S100β, cortisol, and platelet and monocyte counts did not change throughout the neutral-HOI study. The present findings suggested that the increase in BDNF during 20-min hot-HOI was induced by hyperthermia through enhanced production, rather than by changes in permeability of the blood-brain barrier (BBB), platelet clotting mechanisms or secretion from monocytes.
Snake-venom resistance as a mammalian trophic adaptation: lessons from didelphid marsupials.
Voss, Robert S; Jansa, Sharon A
2012-11-01
Mammals that prey on venomous snakes include several opossums (Didelphidae), at least two hedgehogs (Erinaceidae), several mongooses (Herpestidae), several mustelids, and some skunks (Mephitidae). As a group, these taxa do not share any distinctive morphological traits. Instead, mammalian adaptations for ophiophagy seem to consist only in the ability to resist the toxic effects of snake venom. Molecular mechanisms of venom resistance (as indicated by biochemical research on opossums, mongooses, and hedgehogs) include toxin-neutralizing serum factors and adaptive changes in venom-targeted molecules. Of these, toxin-neutralizing serum factors have received the most research attention to date. All of the toxin-neutralizing serum proteins discovered so far in both opossums and mongooses are human α1B-glycoprotein homologs that inhibit either snake-venom metalloproteinases or phospholipase A(2) myotoxins. By contrast, adaptive changes in venom-targeted molecules have received far less attention. The best-documented examples include amino-acid substitutions in mongoose nicotinic acetylcholine receptor that inhibit binding by α-neurotoxins, and amino-acid substitutions in opossum von Willebrand factor (vWF) that are hypothesized to weaken the bond between vWF and coagulopathic C-type lectins. Although multiple mechanisms of venom resistance are known from some species, the proteomic complexity of most snake venoms suggests that the evolved biochemical defences of ophiophagous mammals are likely to be far more numerous than currently recognized. Whereas most previous research in this field has been motivated by the potential for medical applications, venom resistance in ophiophagous mammals is a complex adaptation that merits attention from comparative biologists. Unfortunately, evolutionary inference is currently limited by ignorance about many relevant facts that can only be provided by future research. © 2012 The Authors. Biological Reviews © 2012 Cambridge Philosophical Society.
Navarro-Marí, José María; Gómez-Camarasa, Cristina; Pérez-Ruiz, Mercedes; Sanbonmatsu-Gámez, Sara; Pedrosa-Corral, Irene; Jiménez-Valera, María
2013-01-01
Granada virus (GRV), a new phlebovirus within the Naples serocomplex, has been recently described in phlebotomine sandflies from Spain. The presence of anti-GRV immunoglobulin G (IgG) antibodies was investigated by indirect fluorescence assay (IFA) and neutralization test (NT) in 920 serum samples from the Granada population. By IFA, an overall GRV seroprevalence of 15.8% (N = 145) was observed, significantly increasing up to 65 years. NT was positive in 18% of anti-GRV IFA-positive samples. IgG antibodies against Toscana virus (TOSV), a hyperendemic phlebovirus within Granada province, were detected in 40% of anti-GRV–positive cases. Anti-GRV IgM antibodies were detected in 36 (6.6%) of 547 acute-phase serum samples from individuals with febrile illness, exanthema, and/or acute respiratory infection. All positives were anti-TOSV IgM-negative. GRV may infect humans, with most cases being asymptomatic. The codetection of anti-GRV and anti-TOSV IgG antibodies could be attributable to cross-reactivity or exposure to the same transmission vector. PMID:23419365
Navarro-Marí, José María; Gómez-Camarasa, Cristina; Pérez-Ruiz, Mercedes; Sanbonmatsu-Gámez, Sara; Pedrosa-Corral, Irene; Jiménez-Valera, María
2013-05-01
Granada virus (GRV), a new phlebovirus within the Naples serocomplex, has been recently described in phlebotomine sandflies from Spain. The presence of anti-GRV immunoglobulin G (IgG) antibodies was investigated by indirect fluorescence assay (IFA) and neutralization test (NT) in 920 serum samples from the Granada population. By IFA, an overall GRV seroprevalence of 15.8% (N = 145) was observed, significantly increasing up to 65 years. NT was positive in 18% of anti-GRV IFA-positive samples. IgG antibodies against Toscana virus (TOSV), a hyperendemic phlebovirus within Granada province, were detected in 40% of anti-GRV-positive cases. Anti-GRV IgM antibodies were detected in 36 (6.6%) of 547 acute-phase serum samples from individuals with febrile illness, exanthema, and/or acute respiratory infection. All positives were anti-TOSV IgM-negative. GRV may infect humans, with most cases being asymptomatic. The codetection of anti-GRV and anti-TOSV IgG antibodies could be attributable to cross-reactivity or exposure to the same transmission vector.
Cairns, Tina M; Huang, Zhen-Yu; Gallagher, John R; Lin, Yixin; Lou, Huan; Whitbeck, J Charles; Wald, Anna; Cohen, Gary H; Eisenberg, Roselyn J
2015-09-01
Herpes simplex virus 1 (HSV-1) and HSV-2 infect many humans and establish a latent infection in sensory ganglia. Although some infected people suffer periodic recurrences, others do not. Infected people mount both cell-mediated and humoral responses, including the production of virus-neutralizing antibodies (Abs) directed at viral entry glycoproteins. Previously, we examined IgGs from 10 HSV-seropositive individuals; all neutralized virus and were directed primarily against gD or gD+gB. Here, we expand our studies and examine 32 additional sera from HSV-infected individuals, 23 of whom had no recurrent disease. Using an Octet RED96 system, we screened all 32 serum samples directly for both glycoprotein binding and competition with known neutralizing anti-gD and -gB monoclonal Abs (MAbs). On average, the recurrent cohort exhibited higher binding to gD and gB and had higher neutralization titers. There were similar trends in the blocking of MAbs to critical gD and gB epitopes. When we depleted six sera of Abs to specific glycoproteins, we found different types of responses, but always directed primarily at gD and/or gB. Interestingly, in one dual-infected person, the neutralizing response to HSV-2 was due to gD2 and gB2, whereas HSV-1 neutralization was due to gD1 and gB1. In another case, virus neutralization was HSV-1 specific, with the Ab response directed entirely at gB1, despite this serum blocking type-common anti-gD and -gB neutralizing MAbs. These data are pertinent in the design of future HSV vaccines since they demonstrate the importance of both serotypes of gD and gB as immunogens. We previously showed that people infected with HSV produce neutralizing Abs directed against gD or a combination of gD+gB (and in one case, gD+gB+gC, which was HSV-1 specific). In this more extensive study, we again found that gD or gD+gB can account for the virus neutralizing response and critical epitopes of one or both of these proteins are represented in sera of naturally infected humans. However, we also found that some individuals produced a strong response against gB alone. In addition, we identified type-specific contributions to HSV neutralization from both gD and gB. Contributions from the other entry glycoproteins, gC and gH/gL, were minimal and limited to HSV-1 neutralization. Knowing the variations in how humans see and mount a response to HSV will be important to vaccine development. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Megid, J; Peraçolli, M T; Curi, P R; Zanetti, C R; Cabrera, W H; Vassao, R; Ito, F H
1999-05-14
Using the laboratory mice, Fuenzalida-Palacios mouse brain human rabies vaccine was administered in groups of animals previously inoculated with rabies virus and then submitted to treatments with the immunomodulators onco-BCG, avridine and Propionibacterium acnes. Humoral and cellular immune responses were evaluated through the macrophage inhibition factor (MIF), intra-pad inoculation (IPI) and serum neutralization (SN) tests and by the detection of gamma-interferon (IFN-gamma). The IPI test was not effective in detecting the response of delayed-type hypersensitivity, contrary to MIF, which showed the immune cellular response. Higher levels of IFN-gamma were observed in the groups of mice vaccinated and treated with avridine and P. acnes. Although immunomodulating activities have been detected, the use of adjuvants with the Fuenzalida-Palacios type vaccine in mice did not reveal any encouraging results.
Berentsen, Are R; Dunbar, Mike R; Becker, Matthew S; M'soka, Jassiel; Droge, Egil; Sakuya, Nicholas M; Matandiko, Wigganson; McRobb, Rachel; Hanlon, Cathleen A
2013-09-01
Disease transmission within and among wild and domestic carnivores can have significant impacts on populations, particularly for threatened and endangered species. We used serology to evaluate potential exposure to rabies virus, canine distemper virus (CDV), and canine parvovirus (CPV) for populations of African lions (Panthera leo), African wild dogs (Lycaon pictus), and spotted hyenas (Crocuta crocuta) in Zambia's South Luangwa National Park (SLNP) and Liuwa Plain National Park (LPNP) as well as community lands bordering these areas. In addition, domestic dogs in the study region were evaluated for exposure to CDV and rabies. We provide the first comprehensive disease exposure data for these species in these ecosystems. Twenty-one lions, 20 hyenas, 13 wild dogs, and 38 domestic dogs were sampled across both regions from 2009 to 2011. Laboratory results show 10.5% of domestic dogs, 5.0% of hyenas, and 7.7% of wild dogs sampled were positive for CDV exposure. All lions were negative. Exposure to CPV was 10.0% and 4.8% for hyenas and lions, respectively. All wild dogs were negative, and domestic dogs were not tested due to insufficient serum samples. All species sampled were negative for rabies virus neutralizing antibodies except lions. Forty percent of lions tested positive for rabies virus neutralizing antibodies. Because these lions appeared clinically healthy, this finding is consistent with seroconversion following exposure to rabies antigen. To our knowledge, this finding represents the first ever documentation of rabies virus neutralizing antibodies consistent with rabies exposure that did not lead to clinical disease in free-ranging African lions from this region. With ever-increasing human pressure on these ecosystems, understanding disease transmission dynamics is essential for proper management and conservation of these carnivore species.
Furman, David; Hejblum, Boris P.; Simon, Noah; Jojic, Vladimir; Dekker, Cornelia L.; Thiébaut, Rodolphe; Tibshirani, Robert J.; Davis, Mark M.
2014-01-01
Females have generally more robust immune responses than males for reasons that are not well-understood. Here we used a systems analysis to investigate these differences by analyzing the neutralizing antibody response to a trivalent inactivated seasonal influenza vaccine (TIV) and a large number of immune system components, including serum cytokines and chemokines, blood cell subset frequencies, genome-wide gene expression, and cellular responses to diverse in vitro stimuli, in 53 females and 34 males of different ages. We found elevated antibody responses to TIV and expression of inflammatory cytokines in the serum of females compared with males regardless of age. This inflammatory profile correlated with the levels of phosphorylated STAT3 proteins in monocytes but not with the serological response to the vaccine. In contrast, using a machine learning approach, we identified a cluster of genes involved in lipid biosynthesis and previously shown to be up-regulated by testosterone that correlated with poor virus-neutralizing activity in men. Moreover, men with elevated serum testosterone levels and associated gene signatures exhibited the lowest antibody responses to TIV. These results demonstrate a strong association between androgens and genes involved in lipid metabolism, suggesting that these could be important drivers of the differences in immune responses between males and females. PMID:24367114
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ristow, Sandra S.; Arnzen, Jeanene M.; Leong, JoAnn Ching
Seventeen strains of infectious hematopoietic necrosis virus (IHNV) from different geographical regions and from different fish stocks were typed by polyacrylamide gel electrophoresis, indirect fluorescence with 27 monoclonal antibodies against both the G and N proteins of the virus, and by serum neutralization with six monoclonal anti-glycoprotein antibodies. In addition, many other IHNV isolates have been examined. Studying the isolates with the antibodies has shown that a greater amount of variation exists between isolates than was first predicted by the application of the polyacrylamide technique. Isolates within electrophoretic types I-V may be further classified according to their reactions with themore » monoclonal antibodies in indirect fluorescence. Serum neutralization with selected anti-glycoprotein antibodies in conjunction with fluorescence analysis confirms one of the original findings of Hsu et al. (1986) that two different species in a single facility can be infected with the same isolate. Variation among isolates as measured by reactivity with the monoclonal library appears to be greater within the G protein than within the N protein sequence. 9 refs., 7 figs., 6 tabs.« less
Ergünay, Koray; Özkul, Aykut
2011-04-01
West Nile virus (WNV) infections may trigger febrile conditions and/or neuroinvasive disease in a portion of the exposed individuals. Serosurveillance data from various regions of Turkey indicate WNV activity. The aim of this study was to confirm the antibody specificity of the serum samples via virus neutralization assay, previously reported to be reactive for WNV IgM. The samples originated from two individuals with the preliminary diagnosis of aseptic meningitis/encephalitis of unknown etiology in 2009 and had been classified as probable WNV infections. Cerebrospinal fluid and sera samples of these patients had been evaluated as negative for WNV RNA and IgG antibodies. Only one serum sample could be included in the neutralization assay due to the limited amounts in the current investigation. The sample was observed as positive in dilutions of 1/20 and 1/40, thus confirming the diagnosis of WNV-related central nervous system infection in a 62 year-old female patient from Ankara, Central Anatolia, Turkey.
Brickley, Elizabeth B; Strauch, Carolyn B; Wieland-Alter, Wendy F; Connor, Ruth I; Lin, Shu; Weiner, Joshua A; Ackerman, Margaret E; Arita, Minetaro; Oberste, M Steven; Weldon, William C; Sáez-Llorens, Xavier; Bandyopadhyay, Ananda S; Wright, Peter F
2018-01-17
The impact of inactivated polio vaccines (IPVs) on intestinal mucosal immune responses to live poliovirus is poorly understood. In a 2014 phase 2 clinical trial, Panamanian infants were immunized at 6, 10, and 14 weeks of age with bivalent oral polio vaccine (bOPV) and randomized to receive either a novel monovalent high-dose type 2-specific IPV (mIPV2HD) or a standard trivalent IPV at 14 weeks. Infants were challenged at 18 weeks with a monovalent type 2 oral polio vaccine (mOPV2). Infants' intestinal immune responses during the 3 weeks following challenge were investigated by measuring poliovirus type-specific neutralization and immunoglobulin (Ig) A, IgA1, IgA2, IgD, IgG, and IgM antibodies in stool samples. Despite mIPV2HD's 4-fold higher type 2 polio D-antigen content and heightened serum neutralization profile, mIPV2HD-immunized infants' intestinal immune responses to mOPV2 challenge were largely indistinguishable from those receiving standard IPV. Mucosal responses were tightly linked to evidence of active infection and, in the 79% of participants who shed virus, robust type 2-specific IgA responses and stool neutralization were observed by 2 weeks after challenge. Enhancing IPV-induced serum neutralization does not substantively improve intestinal mucosal immune responses or limit viral shedding on mOPV2 challenge. NCT02111135. © The Author(s) 2018. Published by Oxford University Press for the Infectious Diseases Society of America.
Brickley, Elizabeth B; Strauch, Carolyn B; Wieland-Alter, Wendy F; Connor, Ruth I; Lin, Shu; Weiner, Joshua A; Ackerman, Margaret E; Arita, Minetaro; Oberste, M Steven; Weldon, William C; Sáez-Llorens, Xavier; Bandyopadhyay, Ananda S; Wright, Peter F
2018-01-01
Abstract Background The impact of inactivated polio vaccines (IPVs) on intestinal mucosal immune responses to live poliovirus is poorly understood. Methods In a 2014 phase 2 clinical trial, Panamanian infants were immunized at 6, 10, and 14 weeks of age with bivalent oral polio vaccine (bOPV) and randomized to receive either a novel monovalent high-dose type 2–specific IPV (mIPV2HD) or a standard trivalent IPV at 14 weeks. Infants were challenged at 18 weeks with a monovalent type 2 oral polio vaccine (mOPV2). Infants’ intestinal immune responses during the 3 weeks following challenge were investigated by measuring poliovirus type-specific neutralization and immunoglobulin (Ig) A, IgA1, IgA2, IgD, IgG, and IgM antibodies in stool samples. Results Despite mIPV2HD’s 4-fold higher type 2 polio D–antigen content and heightened serum neutralization profile, mIPV2HD-immunized infants’ intestinal immune responses to mOPV2 challenge were largely indistinguishable from those receiving standard IPV. Mucosal responses were tightly linked to evidence of active infection and, in the 79% of participants who shed virus, robust type 2–specific IgA responses and stool neutralization were observed by 2 weeks after challenge. Conclusions Enhancing IPV-induced serum neutralization does not substantively improve intestinal mucosal immune responses or limit viral shedding on mOPV2 challenge. Clinical Trials Registration NCT02111135. PMID:29304199
Survey of tick-borne zoonotic viruses in wild deer in Hokkaido, Japan.
Uchida, Leo; Hayasaka, Daisuke; Ngwe Tun, Mya Myat; Morita, Kouichi; Muramatsu, Yasukazu; Hagiwara, Katsuro
2018-04-19
Tick-borne encephalitis (TBE) and severe fever with thrombocytopenia syndrome (SFTS) are both tick-borne zoonotic diseases caused by TBE virus (TBEV) and SFTS phlebovirus (SFTSV). In 2016, a second domestic TBE case was reported in Hokkaido, Japan, after an absence of 23 years. We conducted IgG ELISA for TBEV and SFTSV on 314 deer (Cervus nippon yesoensis) serum samples collected from 3 places in Hokkaido. There were 7 seropositive samples for TBEV but none for SFTSV by ELISA. The specificity of the 7 positive samples was confirmed by neutralization tests against TBEV, and 5 sera showed 320 to 640 of 50% focus reduction endpoint titers. Our results provide information about the infectious status of TBEV in wild deer in Hokkaido, Japan.
Rhinovirus antibodies in an isolated Amazon Indian tribe.
Thwing, C J; Arruda, E; Vieira Filho, J P; Castelo Filho, A; Gwaltney, J M
1993-06-01
In early 1985, the Parakana-Apiterewa, a small, primitive Indian tribe, was contacted in the southern Amazon Basin. The tribe was thought to have been totally isolated from civilization until recent development of their land. Blood specimens were collected in 1985, shortly after the discovery of the tribe, and analyzed for the presence of rhinovirus-neutralizing antibody to nine different immunotypes. Six to forty-seven percent of the serum samples tested contained antibody to at least one immunotype of rhinovirus. The prevalence of rhinovirus antibody in the Parakana-Apiterewa Indians was similar to that reported in United States populations, suggesting that there had been considerable direct or indirect contact in the past between tribe members and persons in the outside world.
Liu, Shaohua; Song, Dongmei; Bai, Han; Lu, Weiwei; Dai, Xinxian; Hao, Chunsheng; Zhang, Zhongyang; Guo, Huijie; Zhang, Yue; Li, Xiuling
2017-12-01
With the promotion of inactivated poliomyelitis vaccine (IPV) and live attenuated oral poliomyelitis vaccine (OPV), the global reported cases of poliomyelitis have reduced sharply from 0.35 million in 1988 to 74 in 2015. The Polio Eradication & Endgame Strategic Plan published by WHO in 2013 included the strategy of implementation of poliovirus safe handling and containment measures to minimize the risks of facility-associated reintroduction of virus into the polio-free community to prevent the re-import of poliovirus. Toward this strategy, we produced replication-incompetent pseudovirus of poliovirus type 1, 2, 3 attenuated strains by constructing poliovirus capsid expression vectors and poliovirus replicon then transfecting HEK293T cells and developed a pseudovirus-based neutralization assay (pNA) to determine neutralizing antibody titer which is more secure, time-saving and reliable than conventional neutralization assay (cNA). By using anti-poliovirus rat serum, we demonstrated excellent correlation between neutralizing antibody titers measured by cNA and pNA. It was concluded that pNA can be a potential alternative to replace cNA as a safe and time-saving system for titer determination after live poliovirus's safekeeping. © 2017 Wiley Periodicals, Inc.
Zhang, Qibin; Petyuk, Vladislav A.; Schepmoes, Athena A.; Orton, Daniel J.; Monroe, Matthew E.; Yang, Feng; Smith, Richard D.; Metz, Thomas O.
2009-01-01
Non-enzymatic glycation of tissue proteins has important implications in the development of complications of diabetes mellitus. While electron transfer dissociation (ETD) has been shown to outperform collision-induced dissociation (CID) in sequencing glycated peptides by tandem mass spectrometry, ETD instrumentation is not yet widely available and often suffers from significantly lower sensitivity than CID. In this study, we evaluated different advanced CID techniques (i.e., neutral-loss-triggered MS3 and multi-stage activation) during liquid chromatography/multi-stage mass spectrometric (LC/MSn) analyses of Amadori-modified peptides enriched from human serum glycated in vitro. During neutral-loss-triggered MS3 experiments, MS3 scans triggered by neutral losses of 3 H2O or 3 H2O + HCHO produced similar results in terms of glycated peptide identifications. However, neutral losses of 3 H2O resulted in significantly more glycated peptide identifications during multi-stage activation experiments. Overall, the multi-stage activation approach produced more glycated peptide identifications, while the neutral-loss-triggered MS3 approach resulted in much higher specificity. Both techniques are viable alternatives to ETD for identifying glycated peptides. PMID:18763275
Reichel, Mirja; Heisig, Peter; Kampf, Günter
2008-12-02
Effective neutralization of active agents is essential to obtain valid efficacy results, especially when non-volatile active agents like chlorhexidine digluconate (CHG) are tested. The aim of this study was to determine an effective and non-toxic neutralizing mixture for a propan-1-ol solution containing 2% CHG. Experiments were carried out according to ASTM E 1054-02. The neutralization capacity was tested separately with five challenge microorganisms in suspension, and with a rayon swab carrier. Either 0.5 mL of the antiseptic solution (suspension test) or a saturated swab with the antiseptic solution (carrier test) was added to tryptic soy broth containing neutralizing agents. After the samples were mixed, aliquots were spread immediately and after 3 h of storage at 2 - 8 degrees C onto tryptic soy agar containing a neutralizing mixture. The neutralizer was, however, not consistently effective in the suspension test. Immediate spread yielded a valid neutralization with Staphylococcus aureus, Staphylococcus epidermidis and Corynebacterium jeikeium but not with Micrococcus luteus (p < 0.001) and Candida albicans (p < 0.001). A 3-h storage period of the neutralized active agents in suspension resulted in significant carry-over activity of CHG in addition against Staphylococcus epidermidis (p < 0.001) and Corynebacterium jeikeium (p = 0.044). In the carrier test, the neutralizing mixture was found to be effective and non toxic to all challenge microorganisms when spread immediately. However, after 3 h storage of the neutralized active agents significant carry-over activity of CHG against Micrococcus luteus (p = 0.004; Tukey HSD) was observed. Without effective neutralization in the sampling fluid, non-volatile active ingredients will continue to reduce the number of surviving microorganisms after antiseptic treatment even if the sampling fluid is kept cold straight after testing. This can result in false-positive antiseptic efficacy data. Attention should be paid during the neutralization validation process to the amount of antiseptic solution, the storage time and to the choice of appropriate and sensitive microorganisms.
Bolfa, Pompei; Jeon, Isaac; Loftis, Amanda; Leslie, Teresa; Marchi, Silvia; Sithole, Fortune; Beck, Cecile; Lecollinet, Sylvie; Zientara, Stephan; Hans, Aymeric; Issel, Charles J
2017-10-01
Equines in the West Indies are used for recreational purposes, tourism industry, racing and agriculture or can be found in feral populations. Little is known in the Caribbean basin about the prevalence of some major equine infectious diseases, some with zoonotic potential, listed as reportable by the OIE. Our objective was to study the prevalence of antibodies for West Nile Virus (WNV), Equine Herpes Virus-1 and 4 (EHV-1 and EHV-4), Equine Influenza (EI), Equine Viral Arteritis (EVA) and Equine Infectious Anemia Virus (EIAV) using a retrospective serological convenience study. We used 180 equine serum samples, 140 from horses and 40 from donkeys in St. Kitts, Nevis, and Sint Eustatius, collected between 2006 and 2015 that were tested with ELISA kits and virus neutralization (for WNV and EVA). Combining ELISA with virus neutralization testing, 25 (13.8%) equine sera were WNV positive (a mixture of indigenous and imported equines) and 3 sera (1.6%) showed doubtful results. For EHV-1, 41 equines (23.7%), mean age 6.7 years, were seropositive. For EHV-4, 138 equines were found seropositive (82.8%), mean age 6.3 years. For EI, 49 equines (27.2%), mean age 7.5 years, were seropositive on ELISA, some previously vaccinated horses. No antibodies against EAV were found on virus neutralization testing, although one animal (0.6%), was EAV positive on ELISA. All samples were EIAV negative. The seroprevalence for EHV-1 and EHV-4 is similar to other parts of the world. For the first time in the study location serologic evidence of antibodies against WNV and EI is reported. This was found in both indigenous and imported animals, highlighting the need for developing proper surveillance plans based on complementary methods of virus detection. Further studies will be needed to define the prevalence, rates of transmission, characterize local virus strains, and study their impact on these populations. Copyright © 2017 Elsevier B.V. All rights reserved.
Washburne, Alex D.; Burby, Joshua W.; Lacker, Daniel; ...
2016-09-30
Systems as diverse as the interacting species in a community, alleles at a genetic locus, and companies in a market are characterized by competition (over resources, space, capital, etc) and adaptation. Neutral theory, built around the hypothesis that individual performance is independent of group membership, has found utility across the disciplines of ecology, population genetics, and economics, both because of the success of the neutral hypothesis in predicting system properties and because deviations from these predictions provide information about the underlying dynamics. However, most tests of neutrality are weak, based on static system properties such as species-abundance distributions or themore » number of singletons in a sample. Time-series data provide a window onto a system’s dynamics, and should furnish tests of the neutral hypothesis that are more powerful to detect deviations from neutrality and more informative about to the type of competitive asymmetry that drives the deviation. Here, we present a neutrality test for time-series data. We apply this test to several microbial time-series and financial time-series and find that most of these systems are not neutral. Our test isolates the covariance structure of neutral competition, thus facilitating further exploration of the nature of asymmetry in the covariance structure of competitive systems. Much like neutrality tests from population genetics that use relative abundance distributions have enabled researchers to scan entire genomes for genes under selection, we anticipate our time-series test will be useful for quick significance tests of neutrality across a range of ecological, economic, and sociological systems for which time-series data are available. Here, future work can use our test to categorize and compare the dynamic fingerprints of particular competitive asymmetries (frequency dependence, volatility smiles, etc) to improve forecasting and management of complex adaptive systems.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Washburne, Alex D.; Burby, Joshua W.; Lacker, Daniel
Systems as diverse as the interacting species in a community, alleles at a genetic locus, and companies in a market are characterized by competition (over resources, space, capital, etc) and adaptation. Neutral theory, built around the hypothesis that individual performance is independent of group membership, has found utility across the disciplines of ecology, population genetics, and economics, both because of the success of the neutral hypothesis in predicting system properties and because deviations from these predictions provide information about the underlying dynamics. However, most tests of neutrality are weak, based on static system properties such as species-abundance distributions or themore » number of singletons in a sample. Time-series data provide a window onto a system’s dynamics, and should furnish tests of the neutral hypothesis that are more powerful to detect deviations from neutrality and more informative about to the type of competitive asymmetry that drives the deviation. Here, we present a neutrality test for time-series data. We apply this test to several microbial time-series and financial time-series and find that most of these systems are not neutral. Our test isolates the covariance structure of neutral competition, thus facilitating further exploration of the nature of asymmetry in the covariance structure of competitive systems. Much like neutrality tests from population genetics that use relative abundance distributions have enabled researchers to scan entire genomes for genes under selection, we anticipate our time-series test will be useful for quick significance tests of neutrality across a range of ecological, economic, and sociological systems for which time-series data are available. Here, future work can use our test to categorize and compare the dynamic fingerprints of particular competitive asymmetries (frequency dependence, volatility smiles, etc) to improve forecasting and management of complex adaptive systems.« less
Mbwana, Judica; Ahmed, Hinda J; Ahlman, Karin; Sundaeus, Vivian; Dahlén, Gunnar; Lyamuya, Eligius; Lagergård, Teresa
2003-09-01
Antibodies specific for the cytolethal-distending toxin of Haemophilus ducreyi (HdCDT) complex and for the CdtA, CdtB, and CdtC components were measured by ELISA in the sera of 50 patients with culture and/or PCR proven chancroid, 42 patients with periodontitis, 50 blood donors from Tanzania, 50 blood donors from Sweden. In addition, the biological activity e.g. neutralization capacity of the sera were tested. Our results demonstrate that majority of chancroid patients and healthy individuals had detectable levels of serum antibodies to HdCDT complex and to separate toxin components. However, high levels (> or =100 units) of antibodies to HdCDT complex were significantly more prevalent in the sera of patients with both chancroid and periodontitis than in the sera of the corresponding controls (P=0.001 and P=0.04, respectively). In the sera of the 50 patients with chancroid, antibodies to CdtA, CdtB, and CdtC were detected in 50, 35, and 34 individuals, respectively. Antibodies to CdtC, being less frequently detected than the antibodies to other components, show a good correlation with the neutralizing capacity of sera. High levels of neutralizing antibodies (> or =160) were detected in only 22 and 2% of the patients with chancroid and periodontitis, respectively. The data suggest that the low levels of anti-HdCDT antibodies, which include neutralizing antibodies, may contribute to limited protection in chancroid and since anti-HdCDT antibodies, may be detected in healthy individuals and in patients with certain disease conditions (e.g. periodontitis), they may not be specific markers for chancroid infection.
Lambert, Stacie L.; Aslam, Shahin; Stillman, Elizabeth; MacPhail, Mia; Nelson, Christine; Ro, Bodrey; Sweetwood, Rosemary; Lei, Yuk Man; Woo, Jennifer C.; Tang, Roderick S.
2015-01-01
Background Illness associated with Respiratory Syncytial Virus (RSV) remains an unmet medical need in both full-term infants and older adults. The fusion glycoprotein (F) of RSV, which plays a key role in RSV infection and is a target of neutralizing antibodies, is an attractive vaccine target for inducing RSV-specific immunity. Methodology and Principal Findings BALB/c mice and cotton rats, two well-characterized rodent models of RSV infection, were used to evaluate the immunogenicity of intramuscularly administered RSV vaccine candidates consisting of purified soluble F (sF) protein formulated with TLR4 agonist glucopyranosyl lipid A (GLA), stable emulsion (SE), GLA-SE, or alum adjuvants. Protection from RSV challenge, serum RSV neutralizing responses, and anti-F IgG responses were induced by all of the tested adjuvanted RSV sF vaccine formulations. However, only RSV sF + GLA-SE induced robust F-specific TH1-biased humoral and cellular responses. In mice, these F-specific cellular responses include both CD4 and CD8 T cells, with F-specific polyfunctional CD8 T cells that traffic to the mouse lung following RSV challenge. This RSV sF + GLA-SE vaccine formulation can also induce robust RSV neutralizing titers and prime IFNγ-producing T cell responses in Sprague Dawley rats. Conclusions/Significance These studies indicate that a protein subunit vaccine consisting of RSV sF + GLA-SE can induce robust neutralizing antibody and T cell responses to RSV, enhancing viral clearance via a TH1 immune-mediated mechanism. This vaccine may benefit older populations at risk for RSV disease. PMID:25793508
Moon, Sung-Sil; Groome, Michelle J; Velasquez, Daniel E; Parashar, Umesh D; Jones, Stephanie; Koen, Antoinette; van Niekerk, Nadia; Jiang, Baoming; Madhi, Shabir A
2016-01-15
Live oral rotavirus (RV) vaccines have shown modest efficacy among children in African countries for reasons that are not completely understood. We examined the possible inhibitory effect of preexisting antirotavirus antibodies on immunogenicity of monovalent RV vaccine (RV1). Mother-infant pairs were enrolled at presentation for their routine immunization visit in Soweto, South Africa, when infants were aged 5-8 weeks. Infant serum samples were obtained before the first and second doses of RV1 and 1 month after the second dose. Maternal serum and breast milk samples were obtained prior to administration of each dose of RV1 to infants. RV-specific immunoglobulin G (IgG), IgA, and neutralizing activity in sera of infants and serum or breast milk samples of mothers were measured using enzyme-linked immunosorbent assays or a microneutralization test. Of the 107 serum pairs from infants who were seronegative for RV IgA at enrollment, we observed a strong positive association between IgG titers in pre-dose 1 sera of infants and mothers and significant negative associations between IgG titers in pre-dose 1 sera of infants and seroconversion to RV1 post-dose 1. Similarly, mothers whose infants' IgA seroconverted after RV1 had significantly lower pre-dose 1 IgG titers in sera than those whose infants did not seroconvert. High levels of preexisting serum IgG, including transplacentally acquired maternal IgG, appeared to have an inhibitory effect on the immunogenicity of RV1 among infants and may, in part, contribute to lower efficacy of RV vaccines in this and other low-income settings. Published by Oxford University Press for the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Epidemiological study of pestiviruses in South American camelids in Switzerland.
Mudry, M; Meylan, M; Regula, G; Steiner, A; Zanoni, R; Zanolari, P
2010-01-01
In the context of the ongoing eradication campaign for bovine viral diarrhea virus (BVDV) in cattle in Switzerland, the role of South American camelids (SAC) as a possible virus reservoir needed to be evaluated. To assess and characterize the prevalence of pestivirus infections in SAC in Switzerland. Serum samples collected from 348 animals (40 herds) in 2008 and from 248 animals (39 herds) in 2000 were examined for antibodies against pestiviruses and for the presence of BVDV viral RNA. Cross-sectional study using stratified, representative herd sampling. An indirect BVDV-ELISA was used to analyze serum samples for pestivirus antibodies, and positive samples underwent a serum neutralization test (SNT). Real-time RT-PCR to detect pestiviral RNA was carried out in all animals from herds with at least 1 seropositive animal. In 2008, the overall prevalence of animals positive for antibodies (ELISA) and pestiviral RNA or was 5.75 and 0%, respectively. In 2000, the corresponding prevalences were 3.63 and 0%, respectively. The seroprevalences (SNT) for BVDV, border disease virus or undetermined pestiviruses were estimated to be 0, 1.73, and 4.02% in 2008, and 0.40, 1.21, and 2.02% in 2000, respectively. At the present time, SAC appear to represent a negligible risk of re-infection for the BVDV eradication program in cattle in Switzerland. Copyright © 2010 by the American College of Veterinary Internal Medicine.
Serum biomarkers for acute hepatotoxicity of Echis pyramidum snake venom in rats.
Asmari, Abdulrahman K Al; Khan, Haseeb A; Banah, Faisal A; Buraidi, Ahmed A Al; Manthiri, Rajamohammed A
2015-01-01
Echis pyramidum is a venomous viper responsible for most cases of envenomation in Arabian Peninsula. We determined the acute phase (3-6 h) changes in serum markers of liver function including alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT) and bilirubin in adult male Sprague Dawley rats injected with Echis pyramidum venom (EPV) in the doses of 0.00 (control), 0.25, 0.50 and 1.00 mg/kg bodyweight. We also analyzed markers of oxidative stress including superoxide dismutase (SOD), catalase (CAT), total thiols (T-SH) and thiobarbituric acids reactive substances (TBARS) in liver. The results showed significant and dose- and time-dependent increases in serum ALT, ALP and GGT activities after a single injection of EPV. Serum bilirubin was significantly increased by medium and high doses of EVP after 3 h post-injection and then decreased at 6 h. The low dose of EPV neither affected the activity of SOD nor altered the levels of liver T-SH and TBARS, however, it significantly decreased the activity of CAT at 6 h post-injection of EPV. The medium dose of EPV significantly reduced liver SOD activity after 6 h whereas the high dose significantly reduced the SOD activity at 3 h and 6 h post-dosing. Both medium and high doses of EPV caused significant as well as dose- and time-dependent reductions in liver CAT activities. The high dose significantly reduced T-SH and increased TBARS in rat liver. Further studies are warranted to test the pharmacological potential of early phase antioxidant therapy for neutralizing the toxic effects of EPV.
McGuire, M C; Nogueira, C P; Bartels, C F; Lightstone, H; Hajra, A; Van der Spek, A F; Lockridge, O; La Du, B N
1989-01-01
A point mutation in the gene for human serum cholinesterase was identified that changes Asp-70 to Gly in the atypical form of serum cholinesterase. The mutation in nucleotide 209, which changes codon 70 from GAT to GGT, was found by sequencing a genomic clone and sequencing selected regions of DNA amplified by the polymerase chain reaction. The entire coding sequences for usual and atypical cholinesterases were compared, and no other consistent base differences were found. A polymorphic site near the C terminus of the coded region was detected, but neither allele at this locus segregated consistently with the atypical trait. The nucleotide-209 mutation was detected in all five atypical cholinesterase families examined. There was complete concordance between this mutation and serum cholinesterase phenotypes for all 14 heterozygous and 6 homozygous atypical subjects tested. The mutation causes the loss of a Sau3A1 restriction site; the resulting DNA fragment length polymorphism was verified by electrophoresis of 32P-labeled DNA restriction fragments from usual and atypical subjects. Dot-blot hybridization analysis with a 19-mer allele-specific probe to the DNA amplified by the polymerase chain reaction distinguished between the usual and atypical genotypes. We conclude that the Asp-70----Gly mutation (acidic to neutral amino acid substitution) accounts for reduced affinity of atypical cholinesterase for choline esters and that Asp-70 must be an important component of the anionic site. Heterogeneity in atypical alleles may exist, but the Asp-70 point mutation may represent an appreciable portion of the atypical gene pool. Images PMID:2915989
Detection of antibodies against classical swine fever virus in fecal samples from wild boar.
Seo, Sang won; Sunwoo, Sun young; Hyun, Bang hoon; Lyoo, Young S
2012-12-28
Classical swine fever (CSF) is a contagious viral disease that affects pigs. Wild boars can play an important epidemiological role in CSF outbreaks. In the past decades, studies conducted in many countries have reported that the CSF virus (CSFV) may persist in wild boar populations. The existence of CSFV in the free-ranging wild boar populations was indirectly confirmed by determining the prevalence of antibodies against CSFV in the serum of hunted wild boars. However, analyzing sero-prevalence in hunted wild boars to study the risk of CSF outbreaks is difficult due to insufficient number of samples, limitation of hunting area and biased age distribution of hunted wild boars. To improve this survey method, we collected feces of wild boars from their habitat and tested them using CSFV antibody enzyme-linked immunosorbent assay (ELISA) and CSF virus neutralization (VN) test. In this study, ELISA was found to be highly sensitive for detecting antibodies against CSFV in fecal samples. Most of doubtful or positive results obtained in CSFV ELISA were confirmed by VN tests. Despite the high coincidence rate of antibody-positive samples between CSFV ELISA and VN test, the possibility of false positive reaction should be considered. In the regional distribution, a fact that antibody-positive fecal and serum samples were found in geographically close area was shown. Hence, presence of antibodies in fecal samples may provide vital information regarding the risk of CSF outbreaks in wild boar groups in geographical proximity. Copyright © 2012 Elsevier B.V. All rights reserved.
Kim, Sung Gyun; Kim, Sejoong; Hwang, Young-Hwan; Kim, Kiwon; Oh, Ji Eun; Chung, Wookyung; Oh, Kook-Hwan; Kim, Hyung Jik; Ahn, Curie
2008-06-01
In vitro studies of peritoneal dialysis (PD) solutions demonstrated that a lactate-buffered fluid with neutral pH and low glucose degradation products (LF) has better biocompatibility than a conventional acidic lactate-buffered fluid (CF). However, few clinical trials have evaluated the long-term benefit of the biocompatible solution on residual renal function (RRF). To compare LF with CF, we performed a prospective, randomized study with patients starting PD. After 1-month run-in period, 91 new PD patients were randomized for 12 months of treatment with either LF (Balance: Fresenius Medical Care, Bad Homburg, Germany; n = 48) or CF (Stay Safe: Fresenius; n = 43). We measured RRF, acid-base balance, peritoneal equilibration test, and adequacy of dialysis every 6 months after the run-in period. After 12 months of treatment, the residual glomerular filtration rate (GFR) in patients using LF tended to be higher than that of patients on CF (p = 0.057 by repeated-measures analysis of variance). We observed a significant difference in the changes of residual GFR between the two groups (p = 0.009), a difference that was especially marked in the subgroup whose baseline residual GFR was more than 2 mL/min/1.73 m(2). In addition, serum total CO(2) levels were higher (p = 0.001) and serum anion gap was lower (p = 0.019) in the LF group. We observed no differences between groups for Kt/V, C-reactive protein, or normalized protein equivalent of nitrogen appearance. In incident PD patients with significant residual GFR, LF may better preserve RRF over a 12-month treatment period. Additionally, pH-neutral PD fluid may improve acid-base balance as compared with CF.
Effect of cobalt ions on the interaction between macrophages and titanium.
Pettersson, Mattias; Pettersson, Jean; Thorén, Margareta Molin; Johansson, Anders
2018-04-30
Inflammation and bone reduction around dental implants are described as peri-implantitis and can be caused by an inflammatory response against bacterial products and toxins. Titanium (Ti) forms aggregates with serum proteins, which activate and cause release of the cytokine interleukin (IL-1β) from human macrophages. It was hypothesized that cobalt (Co) ions can interact in the formation of pro-inflammatory aggregates, formed by titanium. To test this hypothesis, we differentiated THP-1 cells into macrophages and exposed them to Ti ions alone or in combination with Co ions to investigate if IL-1β release and cytotoxicity were affected. We also investigated aggregate formation, cell uptake and human biopsies with inductively coupled plasma atomic emission spectroscopy (ICP-AES) and electron microscopy. Co at a concentration of 100 µM neutralized the IL-1β release from human macrophages and affected the aggregate formation. The aggregates formed by Ti could be detected in the cytosol of macrophages. In the presence of Co, the Ti-induced aggregates were located in the cytosol of the cultured macrophages, but outside the lysosomal structures. It is concluded that Co can neutralize the Ti-induced activation and release of active IL-1β from human macrophages in vitro. Also, serum proteins are needed for the formation of metal-protein aggregates in cell medium. Furthermore, the structures of the aggregates as well as the localisation after cellular uptake differ if Co is present in a Ti solution. Phagocytized aggregates with a similar appearance seen in vitro with Ti present, were also visible in a sample from human peri-implant tissue. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.
A Therapeutic Uricase with Reduced Immunogenicity Risk and Improved Development Properties.
Nyborg, Andrew C; Ward, Chris; Zacco, Anna; Chacko, Benoy; Grinberg, Luba; Geoghegan, James C; Bean, Ryan; Wendeler, Michaela; Bartnik, Frank; O'Connor, Ellen; Gruia, Flaviu; Iyer, Vidyashankara; Feng, Hui; Roy, Varnika; Berge, Mark; Miner, Jeffrey N; Wilson, David M; Zhou, Dongmei; Nicholson, Simone; Wilker, Clynn; Wu, Chi Y; Wilson, Susan; Jermutus, Lutz; Wu, Herren; Owen, David A; Osbourn, Jane; Coats, Steven; Baca, Manuel
2016-01-01
Humans and higher primates are unique in that they lack uricase, the enzyme capable of oxidizing uric acid. As a consequence of this enzyme deficiency, humans have high serum uric acid levels. In some people, uric acid levels rise above the solubility limit resulting in crystallization in joints, acute inflammation in response to those crystals causes severe pain; a condition known as gout. Treatment for severe gout includes injection of non-human uricase to reduce serum uric acid levels. Krystexxa® is a hyper-PEGylated pig-baboon chimeric uricase indicated for chronic refractory gout that induces an immunogenic response in 91% of treated patients, including infusion reactions (26%) and anaphylaxis (6.5%). These properties limit its use and effectiveness. An innovative approach has been used to develop a therapeutic uricase with improved properties such as: soluble expression, neutral pH solubility, high E. coli expression level, thermal stability, and excellent activity. More than 200 diverse uricase sequences were aligned to guide protein engineering and reduce putative sequence liabilities. A single uricase lead candidate was identified, which showed low potential for immunogenicity in >200 human donor samples selected to represent diverse HLA haplotypes. Cysteines were engineered into the lead sequence for site specific PEGylation and studies demonstrated >95% PEGylation efficiency. PEGylated uricase retains enzymatic activity in vitro at neutral pH, in human serum and in vivo (rats and canines) and has an extended half-life. In canines, an 85% reduction in serum uric acid levels was observed with a single subcutaneous injection. This PEGylated, non-immunogenic uricase has the potential to provide meaningful benefits to patients with gout.
Habibi, Maximillian S; Jozwik, Agnieszka; Makris, Spyridon; Dunning, Jake; Paras, Allan; DeVincenzo, John P; de Haan, Cornelis A M; Wrammert, Jens; Openshaw, Peter J M; Chiu, Christopher
2015-05-01
Despite relative antigenic stability, respiratory syncytial virus (RSV) reinfects throughout life. After more than 40 years of research, no effective human vaccine exists and correlates of protection remain poorly defined. Most current vaccine candidates seek to induce high levels of RSV-specific serum neutralizing antibodies, which are associated with reduced RSV-related hospitalization rates in observational studies but may not actually prevent infection. To characterize correlates of protection from infection and the generation of RSV-specific humoral memory to promote effective vaccine development. We inoculated 61 healthy adults with live RSV and studied protection from infection by serum and mucosal antibody. We analyzed RSV-specific peripheral blood plasmablast and memory B-cell frequencies and antibody longevity. Despite moderately high levels of preexisting serum antibody, 34 (56%) became infected, of whom 23 (68%) developed symptomatic colds. Prior RSV-specific nasal IgA correlated significantly more strongly with protection from polymerase chain reaction-confirmed infection than serum neutralizing antibody. Increases in virus-specific antibody titers were variable and transient in infected subjects but correlated with plasmablasts that peaked around Day 10. During convalescence, only IgG (and no IgA) RSV-specific memory B cells were detectable in peripheral blood. This contrasted with natural influenza infection, in which virus-specific IgA memory B cells were readily recovered. This observed specific defect in IgA memory may partly explain the ability of RSV to cause recurrent symptomatic infections. If so, vaccines able to induce durable RSV-specific IgA responses may be more protective than those generating systemic antibody alone.
Effects of potassium bicarbonate supplements on circulating microRNA expression
USDA-ARS?s Scientific Manuscript database
Several studies suggest that neutralizing the acid load in the diet with alkali has favorable effects on intermediate markers of musculoskeletal health. We examined whether alkali supplementation with potassium bicarbonate (KHCO3; 81 mmol/d, n=12) vs. placebo (n=12) for 84 days altered serum microRN...
Selected HIV-1 Env Trimeric Formulations Act as Potent Immunogens in a Rabbit Vaccination Model
Heyndrickx, Leo; Stewart-Jones, Guillaume; Jansson, Marianne; Schuitemaker, Hanneke; Bowles, Emma; Buonaguro, Luigi; Grevstad, Berit; Vinner, Lasse; Vereecken, Katleen; Parker, Joe; Ramaswamy, Meghna; Biswas, Priscilla; Vanham, Guido; Scarlatti, Gabriella; Fomsgaard, Anders
2013-01-01
Background Ten to 30% of HIV-1 infected subjects develop broadly neutralizing antibodies (bNAbs) during chronic infection. We hypothesized that immunizing rabbits with viral envelope glycoproteins (Envs) from these patients may induce bNAbs, when formulated as a trimeric protein and in the presence of an adjuvant. Methods Based on in vitro neutralizing activity in serum, patients with bNAbs were selected for cloning of their HIV-1 Env. Seven stable soluble trimeric gp140 proteins were generated from sequences derived from four adults and two children infected with either clade A or B HIV-1. From one of the clade A Envs both the monomeric and trimeric Env were produced for comparison. Rabbits were immunized with soluble gp120 or trimeric gp140 proteins in combination with the adjuvant dimethyl dioctadecyl ammonium/trehalose dibehenate (CAF01). Env binding in rabbit immune serum was determined using ELISAs based on gp120-IIIB protein. Neutralizing activity of IgG purified from rabbit immune sera was measured with the pseudovirus-TZMbl assay and a PBMC-based neutralization assay for selected experiments. Results It was initially established that gp140 trimers induce better antibody responses over gp120 monomers and that the adjuvant CAF01 was necessary for such strong responses. Gp140 trimers, based on HIV-1 variants from patients with bNAbs, were able to elicit both gp120IIIB specific IgG and NAbs to Tier 1 viruses of different subtypes. Potency of NAbs closely correlated with titers, and an gp120-binding IgG titer above a threshold of 100,000 was predictive of neutralization capability. Finally, peptide inhibition experiments showed that a large fraction of the neutralizing IgG was directed against the gp120 V3 region. Conclusions Our results indicate that the strategy of reverse immunology based on selected Env sequences is promising when immunogens are delivered as stabilized trimers in CAF01 adjuvant and that the rabbit is a valuable model for HIV vaccine studies. PMID:24023951
Ledgerwood, J E; Coates, E E; Yamshchikov, G; Saunders, J G; Holman, L; Enama, M E; DeZure, A; Lynch, R M; Gordon, I; Plummer, S; Hendel, C S; Pegu, A; Conan-Cibotti, M; Sitar, S; Bailer, R T; Narpala, S; McDermott, A; Louder, M; O'Dell, S; Mohan, S; Pandey, J P; Schwartz, R M; Hu, Z; Koup, R A; Capparelli, E; Mascola, J R; Graham, B S
2015-12-01
VRC-HIVMAB060-00-AB (VRC01) is a broadly neutralizing HIV-1 monoclonal antibody (mAb) isolated from the B cells of an HIV-infected patient. It is directed against the HIV-1 CD4 binding site and is capable of potently neutralizing the majority of diverse HIV-1 strains. This Phase I dose-escalation study in healthy adults was conducted at the National Institutes of Health (NIH) Clinical Center (Bethesda, MD, USA). Primary objectives were the safety, tolerability and pharmacokinetics (PK) of VRC01 intravenous (i.v.) infusion at 5, 20 or 40 mg/kg, given either once (20 mg/kg) or twice 28 days apart (all doses), and of subcutaneous (s.c.) delivery at 5 mg/kg compared to s.c. placebo given twice, 28 days apart. Cumulatively, 28 subjects received 43 VRC01 and nine received placebo administrations. There were no serious adverse events or dose-limiting toxicities. Mean 28-day serum trough concentrations after the first infusion were 35 and 57 μg/ml for groups infused with 20 mg/kg (n = 8) and 40 mg/kg (n = 5) doses, respectively. Mean 28-day trough concentrations after the second infusion were 56 and 89 μg/ml for the same two doses. Over the 5-40 mg/kg i.v. dose range (n = 18), the clearance was 0.016 l/h and terminal half-life was 15 days. After infusion VRC01 retained expected neutralizing activity in serum, and anti-VRC01 antibody responses were not detected. The human monoclonal antibody (mAb) VRC01 was well tolerated when delivered i.v. or s.c. The mAb demonstrated expected half-life and pharmacokinetics for a human immunoglobulin G. The safety and PK results support and inform VRC01 dosing schedules for planning HIV-1 prevention efficacy studies. © 2015 British Society for Immunology.
Antibody neutralization of retargeted measles viruses.
Lech, Patrycja J; Pappoe, Roland; Nakamura, Takafumi; Tobin, Gregory J; Nara, Peter L; Russell, Stephen J
2014-04-01
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. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.
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 effective vaccine that generates both T cell responses and neutralizing antibodies is required to eradicate the disease. Regions within the HCV surface glycoproteins E1 and E2 are essential for virus entry and are targets for neutralizing antibodies. Screening of vaccine candidates requires suitable panels of glycoproteins that represent the breadth of neutralization resistance. Use of a standard reference panel for vaccine studies will ensure comparability of data sets, as has become routine for HIV-1. Here, we describe a large panel of patient-derived HCV glycoproteins with an assessment of their neutralization sensitivity to defined monoclonal antibodies, which has enabled us to predict their likely efficacy in the wider HCV-infected population. The panel could also be important for future selection of additional therapeutic antibodies and for vaccine design. Copyright © 2016 Urbanowicz et al.
Marzi, Andrea; Yoshida, Reiko; Miyamoto, Hiroko; Ishijima, Mari; Suzuki, Yasuhiko; Higuchi, Megumi; Matsuyama, Yukie; Igarashi, Manabu; Nakayama, Eri; Kuroda, Makoto; Saijo, Masayuki; Feldmann, Friederike; Brining, Douglas; Feldmann, Heinz; Takada, Ayato
2012-01-01
Ebola virus (EBOV) is the causative agent of severe hemorrhagic fever in primates, with human case fatality rates up to 90%. Today, there is neither a licensed vaccine nor a treatment available for Ebola hemorrhagic fever (EHF). Single monoclonal antibodies (MAbs) specific for Zaire ebolavirus (ZEBOV) have been successfully used in passive immunization experiments in rodent models, but have failed to protect nonhuman primates from lethal disease. In this study, we used two clones of human-mouse chimeric MAbs (ch133 and ch226) with strong neutralizing activity against ZEBOV and evaluated their protective potential in a rhesus macaque model of EHF. Reduced viral loads and partial protection were observed in animals given MAbs ch133 and ch226 combined intravenously at 24 hours before and 24 and 72 hours after challenge. MAbs circulated in the blood of a surviving animal until virus-induced IgG responses were detected. In contrast, serum MAb concentrations decreased to undetectable levels at terminal stages of disease in animals that succumbed to infection, indicating substantial consumption of these antibodies due to virus replication. Accordingly, the rapid decrease of serum MAbs was clearly associated with increased viremia in non-survivors. Our results indicate that EBOV neutralizing antibodies, particularly in combination with other therapeutic strategies, might be beneficial in reducing viral loads and prolonging disease progression during EHF.
Reichel, Mirja; Heisig, Peter; Kampf, Günter
2008-01-01
Background Effective neutralization of active agents is essential to obtain valid efficacy results, especially when non-volatile active agents like chlorhexidine digluconate (CHG) are tested. The aim of this study was to determine an effective and non-toxic neutralizing mixture for a propan-1-ol solution containing 2% CHG. Methods Experiments were carried out according to ASTM E 1054-02. The neutralization capacity was tested separately with five challenge microorganisms in suspension, and with a rayon swab carrier. Either 0.5 mL of the antiseptic solution (suspension test) or a saturated swab with the antiseptic solution (carrier test) was added to tryptic soy broth containing neutralizing agents. After the samples were mixed, aliquots were spread immediately and after 3 h of storage at 2 – 8°C onto tryptic soy agar containing a neutralizing mixture. Results The neutralizer was, however, not consistently effective in the suspension test. Immediate spread yielded a valid neutralization with Staphylococcus aureus, Staphylococcus epidermidis and Corynebacterium jeikeium but not with Micrococcus luteus (p < 0.001) and Candida albicans (p < 0.001). A 3-h storage period of the neutralized active agents in suspension resulted in significant carry-over activity of CHG in addition against Staphylococcus epidermidis (p < 0.001) and Corynebacterium jeikeium (p = 0.044). In the carrier test, the neutralizing mixture was found to be effective and non toxic to all challenge microorganisms when spread immediately. However, after 3 h storage of the neutralized active agents significant carry-over activity of CHG against Micrococcus luteus (p = 0.004; Tukey HSD) was observed. Conclusion Without effective neutralization in the sampling fluid, non-volatile active ingredients will continue to reduce the number of surviving microorganisms after antiseptic treatment even if the sampling fluid is kept cold straight after testing. This can result in false-positive antiseptic efficacy data. Attention should be paid during the neutralization validation process to the amount of antiseptic solution, the storage time and to the choice of appropriate and sensitive microorganisms. PMID:19046465
A tetravalent dengue nanoparticle stimulates antibody production in mice.
Silva, Elisângela F; Orsi, Mariana; Andrade, Angela L; Domingues, Rosana Z; Silva, Breno M; de Araújo, Helena R C; Pimenta, Paulo F P; Diamond, Michael S; Rocha, Eliseu S O; Kroon, Erna G; Malaquias, Luiz C C; Coelho, Luiz F L
2012-03-22
Dengue is a major public health problem worldwide, especially in the tropical and subtropical regions of the world. Infection with a single Dengue virus (DENV) serotype causes a mild, self-limiting febrile illness called dengue fever. However, a subset of patients experiencing secondary infection with a different serotype progresses to the severe form of the disease, dengue hemorrhagic fever/dengue shock syndrome. Currently, there are no licensed vaccines or antiviral drugs to prevent or treat dengue infections. Biodegradable nanoparticles coated with proteins represent a promising method for in vivo delivery of vaccines. Here, we used a murine model to evaluate the IgG production after administration of inactivated DENV corresponding to all four serotypes adsorbed to bovine serum albumin nanoparticles. This formulation induced a production of anti-DENV IgG antibodies (p < 0.001). However, plaque reduction neutralization assays with the four DENV serotypes revealed that these antibodies have no neutralizing activity in the dilutions tested. Our results show that while the nanoparticle system induces humoral responses against DENV, further investigation with different DENV antigens will be required to improve immunogenicity, epitope specicity, and functional activity to make this platform a viable option for DENV vaccines.
Yakobson, B; Taylor, N; Dveres, N; Rotblat, S; Spero, Ż; Lankau, E W; Maki, J
2017-06-01
Rabies is endemic in wildlife or domestic carnivore populations globally. Infection of domestic dogs is of particular concern in many areas. In regions where domestic animals are at risk of exposure to rabies virus, dogs should be routinely vaccinated against rabies to protect both pet and human populations. Many countries require demonstration of an adequate level of serum rabies neutralizing antibodies to permit entry of dogs during international travel. We analysed rabies titres of dogs seeking travel certification in Israel to assess demographic and vaccine history factors associated with antibody titres below the acceptable threshold for travel certification. Having received only one previous rabies vaccination and a longer duration since the most recent vaccination was received were primary risk factors for not achieving an adequate rabies virus neutralizing antibody titre for travel certification. These risk factors had stronger effects in younger animals, but were consistent for dogs of all ages. In particular, these findings reiterate the importance of administering at least two rabies vaccinations (the primo vaccination and subsequent booster) to ensure population-level protection against rabies in dogs globally. © 2016 Blackwell Verlag GmbH.
Tse, Longping Victor; Klinc, Kelli A; Madigan, Victoria J; Castellanos Rivera, Ruth M; Wells, Lindsey F; Havlik, L Patrick; Smith, J Kennon; Agbandje-McKenna, Mavis; Asokan, Aravind
2017-06-13
Preexisting neutralizing antibodies (NAbs) against adeno-associated viruses (AAVs) pose a major, unresolved challenge that restricts patient enrollment in gene therapy clinical trials using recombinant AAV vectors. Structural studies suggest that despite a high degree of sequence variability, antibody recognition sites or antigenic hotspots on AAVs and other related parvoviruses might be evolutionarily conserved. To test this hypothesis, we developed a structure-guided evolution approach that does not require selective pressure exerted by NAbs. This strategy yielded highly divergent antigenic footprints that do not exist in natural AAV isolates. Specifically, synthetic variants obtained by evolving murine antigenic epitopes on an AAV serotype 1 capsid template can evade NAbs without compromising titer, transduction efficiency, or tissue tropism. One lead AAV variant generated by combining multiple evolved antigenic sites effectively evades polyclonal anti-AAV1 neutralizing sera from immunized mice and rhesus macaques. Furthermore, this variant displays robust immune evasion in nonhuman primate and human serum samples at dilution factors as high as 1:5, currently mandated by several clinical trials. Our results provide evidence that antibody recognition of AAV capsids is conserved across species. This approach can be applied to any AAV strain to evade NAbs in prospective patients for human gene therapy.
A subunit vaccine against the adenovirus egg-drop syndrome using part of its fiber protein.
Fingerut, E; Gutter, B; Gallili, G; Michael, A; Pitcovski, J
2003-06-20
In this study, the effectiveness of antibodies against the hexon, fiber or a fiber fragment of an avian adenovirus egg-drop syndrome (EDS), in neutralizing the virus was tested. The fiber protein is responsible for binding the virus to the target cell. The fiber fragment knob-s comprises the carboxy-terminal knob domain and 34 amino acids of the immediately adjacent shaft domain of the adenovirus fiber protein. The hexon, fiber capsid protein and knob-s were produced in E. coli and injected into chickens. Antibodies that were produced against the whole fiber protein showed some hemagglutination inhibition (HI) activity. Antibodies produced against the knob-s protein showed HI activity and serum neutralization (SN) activity similar to the positive control-whole virus vaccine. We assume that production of only part of the fiber enables the protein produced in E. coli to fold correctly. Antibodies produced against the hexon protein showed no SN activity. In summary, knob-s induced SN and HI antibodies against EDS virus at a rate similar to the whole virus and were significantly more efficient than the full-length fiber. The recombinant knob-s protein may be used as a vaccine against pathogenic adenovirus infections.
Hoover, E A; Schaller, J P; Mathes, L E; Olsen, R G
1977-01-01
Antibodies against feline leukemia virus (FeLV) and the feline oncornavirus-associated cell membrane antigen (FOCMA) were transferred from pregnant cats to their suckling kittens. All of these kittens were protected against infection and oncogenesis by virulent FeLV when challenged at 2 weeks of age. Suckling kittens acquired 25 to 100% of maternal virus-neutralizing and FOCMA titers by 3 days of age, and titers underwent linear decay to undetectable levels by 2 to 3 months of age. FOCMA antibody in dams and kittens was identified as immunoglobulin G (IgG) by use of goat anti-human IgG serum, which cross-reacts with feline IgG in the indirect membrane immunofluorescence test for FOCMA antibody. In an attempt to induce protective maternal antibody by vaccination, 10 pregnant cats were immunized by three to five weekly intramuscular injections with purified FeLV inactivated by ultraviolet irradiation. After the course of immunization, neither virus-neutralizing nor FOCMA antibody was detectable in the dams or in 19 kittens born to these cats. When these kittens were challenged with FeLV at 2 weeks of age, 18 of 19 developed persistent viremia and FeLV-related disease. Images PMID:194840
Chen, Qi; Thomas, Joseph T; Giménez-Lirola, Luis G; Hardham, John M; Gao, Qinshan; Gerber, Priscilla F; Opriessnig, Tanja; Zheng, Ying; Li, Ganwu; Gauger, Phillip C; Madson, Darin M; Magstadt, Drew R; Zhang, Jianqiang
2016-04-05
At least two genetically different porcine epidemic diarrhea virus (PEDV) strains have been identified in the United States (U.S. PEDV prototype and S-INDEL-variant strains). The current serological assays offered at veterinary diagnostic laboratories for detection of PEDV-specific antibody are based on the U.S. PEDV prototype strain. The objectives of this study were: 1) isolate the U.S. PEDV S-INDEL-variant strain in cell culture; 2) generate antisera against the U.S. PEDV prototype and S-INDEL-variant strains by experimentally infecting weaned pigs; 3) determine if the various PEDV serological assays could detect antibodies against the U.S. PEDV S-INDEL-variant strain and vice versa. A U.S. PEDV S-INDEL-variant strain was isolated in cell culture in this study. Three groups of PEDV-negative, 3-week-old pigs (five pigs per group) were inoculated orally with a U.S. PEDV prototype isolate (previously isolated in our lab), an S-INDEL-variant isolate or virus-negative culture medium. Serum samples collected at 0, 7, 14, 21 and 28 days post inoculation were evaluated by the following PEDV serological assays: 1) indirect fluorescent antibody (IFA) assays using the prototype and S-INDEL-variant strains as indicator viruses; 2) virus neutralization (VN) tests against the prototype and S-INDEL-variant viruses; 3) PEDV prototype strain whole virus based ELISA; 4) PEDV prototype strain S1-based ELISA; and 5) PEDV S-INDEL-variant strain S1-based ELISA. The positive antisera against the prototype strain reacted to and neutralized both prototype and S-INDEL-variant viruses, and the positive antisera against the S-INDEL-variant strain also reacted to and neutralized both prototype and S-INDEL-variant viruses, as examined by IFA antibody assays and VN tests. Antibodies against the two PEDV strains could be detected by all three ELISAs although detection rates varied to some degree. These data indicate that the antibodies against U.S. PEDV prototype and S-INDEL-variant strains cross-reacted and cross-neutralized both strains in vitro. The current serological assays based on U.S. PEDV prototype strain can detect antibodies against both U.S. PEDV strains.
A hollow cathode neutralizer for a 30-cm diameter bombardment thruster
NASA Technical Reports Server (NTRS)
Bechtel, R. T.
1973-01-01
Recent improvements in overall thrustor performance have imposed new constraints on neutralizer performance. The use of compensated grid extraction system requires a re-evaluation of neutralizer position. In addition a suitable control logic for the neutralizer has proven difficult. A series of tests were conducted to determine what effect neutralizer cathode geometry has on performance. The parameters investigated included orifice diameter and length, and cathode diameter. Similar tests investigated open and enclosed keeper geometries. Neutralizer position tests with compensated grids suggest positions approximately 10 cm from the accelerator and radially out of the beam envelope should result in satisfactory performance and long life. Finally operation at keeper currents of 1.5 amp has resulted in lower total neutralizer power, the elimination of tip heater power, and suitable closed loop control of the neutralizer vaporizer.
Neutralization efficiency of alcohol based products used for rapid hand disinfection
Chojecka, Agnieszka; Tarka, Patryk; Kierzkowska, Anna; Nitsch-Osuch, Aneta; Kanecki, Krzysztof
Alcohols are the most commonly used active substances in preparations for quick hand disinfection. They should be bactericidal in very short contact time. PN-EN 13727 + A2: 2015-12 standard, for testing hygienic and surgical handrub disinfection preparations, provides mandatory test conditions of disinfectants in contact times with the range of 30 s to 60 s (hygienic handrub disinfection) and 60 s to 5 min (surgical handrub disinfection). A short contact times for hand hygiene products require a short time of neutralization process. For contact times less than or equal to 10 minutes, the estimated neutralization time is 10 s ± 1 s. Neutralization is a process that abolishes the action of disinfectants. Correct application of this process allows for proper use of disinfectants in practice and its biocidal effect. Objectives. Verification of the effectiveness of 10-second neutralization time of alcohol based preparations for hygienic handrub disinfection Neutralization of two products with different ethanol content (89% and 70%) for hygienic handrub disinfection according to PN-EN 13727 + A2: 2015-12 was investigated. The effectiveness of the neutralizer was assessed by determining toxicity of neutralizer, activity of residual effects of the tested products and their derivatives produced during neutralization (10 s) for test organisms (Staphylococcus aureus ATCC 6538; Pseudomonas aeruginosa ATCC 15442; Enterococcus hirae ATCC 10541; Escherichia coli K12 NCTC 10538) The 10-second neutralization time was sufficient to eliminate the residual activity of products for hygienic handrub disinfection with differentiated ethanol concentration. The neutralizer used did not show toxicity to bacteria and did not produce toxic products with tested preparations after neutralization Conclusions. The use of 10-second neutralization time allows in a precise way designate the contact times for hygienic handrub disinfection products
Otrashevskaia, E V; Krasil'nikov, I V; Ignat'ev, G M
2010-01-01
Postvaccination immunity was studied in the children and teenagers without a history of clinical mumps infection, who had been immunized with the Leningrad-3 mumps vaccine. The level of specific lgG in ELISA and that and spectrum of their neutralizing activity against a vaccine strain and three heterologous mumps virus (MV) strains (genotypes A, C, and H) were measured. The investigation included 151 sera from the vaccinees aged 3 to 17 years, possessing the detectable specific IgG titers in ELISA and the detectable neutralizing titers against the vaccine strain. 97.4% of the vaccinees had neutralizing activity against 1-3 heterologous MV strains. A preponderance of neutralizing titers against heterologous MV strains by 1-log2 in some sera (6.5-32.5 depending on age) was most likely to suggest that the vaccinees' had been in contact with these virus strains in the past. In our investigation, a combination of positive IgG titers and neutralizing titers against the vaccine strain 2-log2 or higher provided the protection of the vaccinated children and teenagers against the symptomatic infection. There was a pronounced buster effect of the second immunization and a drop in the neutralizing activity of the sera from the vaccinated children and adolescents over time after the first and second immunization.
Neutrality between Government and Religion.
ERIC Educational Resources Information Center
Mawdsley, Ralph D.
1996-01-01
The overall guiding principle of neutrality between government and religion masks a tension that exists between free exercise of religion and establishment of religion. Reviews the development and current status of "Lemon" as a test for neutrality; proposes a new test for neutrality, evenhandedness, that is common to both the Free…
The neutralizing role of IgM during early Chikungunya virus infection
Chua, Chong-Long; Chiam, Chun-Wei; Chan, Yoke-Fun
2017-01-01
The antibody isotype IgM appears earlier than IgG, within days of onset of symptoms, and is important during the early stages of the adaptive immune response. Little is known about the functional role of IgM during infection with chikungunya virus (CHIKV), a recently reemerging arbovirus that has caused large global outbreaks. In this study, we studied antibody responses in 102 serum samples collected during CHIKV outbreaks in Malaysia. We described the neutralizing role of IgM at different times post-infection and examined the independent contributions of IgM and IgG towards the neutralizing capacity of human immune sera during the early phase of infection, including the differences in targets of neutralizing epitopes. Neutralizing IgM starts to appear as early as day 4 of symptoms, and their appearance from day 6 is associated with a reduction in viremia. IgM acts in a complementary manner with the early IgG, but plays the main neutralizing role up to a point between days 4 and 10 which varies between individuals. After this point, total neutralizing capacity is attributable almost entirely to the robust neutralizing IgG response. IgM preferentially binds and targets epitopes on the CHIKV surface E1-E2 glycoproteins, rather than individual E1 or E2. These findings provide insight into the early antibody responses to CHIKV, and have implications for design of diagnostic serological assays. PMID:28182795
Rieille, Nadia; Klaus, Christine; Hoffmann, Donata; Péter, Olivier; Voordouw, Maarten J
2017-07-11
Tick-borne encephalitis (TBE) is an important tick-borne disease in Europe. Detection of the TBE virus (TBEV) in local populations of Ixodes ricinus ticks is the most reliable proof that a given area is at risk for TBE, but this approach is time-consuming and expensive. A cheaper and simpler approach is to use immunology-based methods to screen vertebrate hosts for TBEV-specific antibodies and subsequently test the tick populations at locations with seropositive animals. The purpose of the present study was to use goats as sentinel animals to identify new risk areas for TBE in the canton of Valais in Switzerland. A total of 4114 individual goat sera were screened for TBEV-specific antibodies using immunological methods. According to our ELISA assay, 175 goat sera reacted strongly with TBEV antigen, resulting in a seroprevalence rate of 4.3%. The serum neutralization test confirmed that 70 of the 173 ELISA-positive sera had neutralizing antibodies against TBEV. Most of the 26 seropositive goat flocks were detected in the known risk areas in the canton of Valais, with some spread into the connecting valley of Saas and to the east of the town of Brig. One seropositive site was 60 km to the west of the known TBEV-endemic area. At two of the three locations where goats were seropositive, the local tick populations also tested positive for TBEV. The combined approach of screening vertebrate hosts for TBEV-specific antibodies followed by testing the local tick population for TBEV allowed us to detect two new TBEV foci in the canton of Valais. The present study showed that goats are useful sentinel animals for the detection of new TBEV risk areas.
McGibbon, Emily; Moy, Morgan; Vora, Neil M; Dupuis, Alan; Fine, Annie; Kulas, Karen; Limberger, Ronald; Liu, Dakai; Rakeman, Jennifer; St George, Kirsten; Slavinski, Sally
2018-05-09
An outbreak of Zika virus (ZIKV) began in May 2015 in Brazil and rapidly spread throughout the Americas; New York City (NYC) has a diverse population with ∼1.8 million residents who were born in ZIKV-affected areas. Before July 24, 2017, the Centers for Disease Control and Prevention (CDC) ZIKV testing recommendations included nucleic acid amplification-based tests for serum and urine specimens collected ≤14 days of illness onset or last potential exposure, and ZIKV immunoglobulin M (IgM) assay when ZIKV RNA is not detected or for specimens collected within 2-12 weeks of illness onset or last potential exposure, followed by a plaque reduction neutralization test (PRNT). However, the New York public health laboratories and commercial laboratories tested specimens collected beyond these time frames. We analyzed 1080 noncongenital ZIKV cases in NYC residents who met the Council for State and Territorial Epidemiologist's ZIKV case definitions. Among cases, 98% were travel associated, 1% were sexually transmitted, and 1% had unknown exposures; 412 (38%) cases were pregnant women. Of 672 patients with ZIKV RNA detected in serum or urine specimens, 48 (7%) tested positive >14 days after either symptom onset or last potential exposure date (range 15-99 days). Of 390 patients diagnosed based on serology alone (i.e., not tested or not detectable for ZIKV RNA), 60 (15%) had a positive ZIKV IgM and PRNT >12 weeks after symptom onset or last potential exposure date (range 85-273 days). Our findings correspond with CDC's updated guidance to test symptomatic pregnant women up to 12 weeks past onset of symptoms. ZIKV IgM antibody testing may also be warranted for pregnant women regardless of symptoms if their exposure occurred during their pregnancy or periconception period. Providers should understand the scope of diagnostic testing and its limitations to appropriately counsel patients, especially pregnant women.
PURIFICATION OF THE SOLUBLE HEMOLYSINS OF LISTERIA MONOCYTOGENES
Jenkins, E. M.; Njoku-Obi, A. N.; Adams, E. W.
1964-01-01
Jenkins, E. M. (Tuskegee Institute, Tuskegee, Ala.), A. N. Njoku-Obi, and E. W. Adams. Purification of the soluble hemolysins of Listeria monocytogenes. J. Bacteriol. 88:418–424. 1964.—A method is described for obtaining relatively purified hemolysin preparations from both virulent and avirulent strains of Listeria monocytogenes. These hemolysins are protein in nature as shown by heat lability, nondialyzable properties, precipitation with trichloroacetic acid, and electrophoretic mobility. The hemolysins are antigenic in rabbits as shown by serum neutralization tests. The potency of the purified hemolysin was markedly increased by cysteine, sodium hydrosulfite, and a number of reducing agents. Many of the actions of the purified hemolysin seemed to parallel that of streptolysin O, and certain of these activities could be explained by the “thioldisulfide hypothesis.” PMID:14203359
USDA-ARS?s Scientific Manuscript database
Because vaccines for use in commercial poultry against avian influenza (AI) are mainly inactivated and delivered parenterally, our knowledge of protective immunity of poultry against AI is largely based on the induction of serum-neutralizing antibodies produced against a specific hemagglutinin (HA) ...
Monkos, Karol
2013-03-01
The paper presents the results of viscosity determinations on aqueous solutions of human serum albumin (HSA) at isoelectric point over a wide range of concentrations and at temperatures ranging from 5°C to 45°C. On the basis of a modified Arrhenius equation and Mooney's formula some hydrodynamic parameters were obtained. They are compared with those previously obtained for HSA in solutions at neutral pH. The activation energy and entropy of viscous flow and the intrinsic viscosity reach a maximum value, and the effective specific volume, the self-crowding factor and the Huggins coefficient a minimum value in solutions at isoelectric point. Using the dimensionless parameter [η]c, the existence of three ranges of concentrations: diluted, semi-diluted and concentrated, was shown. By applying Lefebvre's relation for the relative viscosity in the semi-dilute regime, the Mark-Houvink-Kuhn-Sakurada (MHKS) exponent was established. The analysis of the results obtained from the three ranges of concentrations showed that both conformation and stiffness of HSA molecules in solutions at isoelectric point and at neutral pH are the same.
Austin, S. Kyle; Dowd, Kimberly A.; Shrestha, Bimmi; Nelson, Christopher A.; Edeling, Melissa A.; Johnson, Syd; Pierson, Theodore C.; Diamond, Michael S.; Fremont, Daved H.
2012-01-01
We previously developed a panel of neutralizing monoclonal antibodies against Dengue virus (DENV)-1, of which few exhibited inhibitory activity against all DENV-1 genotypes. This finding is consistent with reports observing variable neutralization of different DENV strains and genotypes using serum from individuals that experienced natural infection or immunization. Herein, we describe the crystal structures of DENV1-E111 bound to a novel CC′ loop epitope on domain III (DIII) of the E protein from two different DENV-1 genotypes. Docking of our structure onto the available cryo-electron microscopy models of DENV virions revealed that the DENV1-E111 epitope was inaccessible, suggesting that this antibody recognizes an uncharacterized virus conformation. While the affinity of binding between DENV1-E111 and DIII varied by genotype, we observed limited correlation with inhibitory activity. Instead, our results support the conclusion that potent neutralization depends on genotype-dependent exposure of the CC′ loop epitope. These findings establish new structural complexity of the DENV virion, which may be relevant for the choice of DENV strain for induction or analysis of neutralizing antibodies in the context of vaccine development. PMID:23055922
Yu, Yanbin; Piddington, Christopher; Fitzpatrick, Dan; Twomey, Brian; Xu, Ren; Swanson, Steven J; Jing, Shuqian
2006-10-20
The presence of neutralizing antibodies against protein therapeutics is a concern in the biomedical field. Such antibodies not only reduce the efficacy of protein therapeutics, but also impose potential dangers to the patients receiving them. To date, a small number of in vitro cell-based bioassays for detecting neutralizing antibodies against therapeutic proteins have been developed. Most of the existing assays, however, either involve the use of radioactive materials or have limited sensitivities and/or poor specificities. With advances in mRNA profiling and detection techniques, we have established a novel and non-radioactive bioassay system using branched DNA (bDNA) technology for detecting protein-therapeutic neutralizing antibodies in patient serum. Our assay measures the variations of target gene expression that reflect the biologic effect of the therapeutic agent and the capability of the antibodies, if present, to neutralize the therapeutics. Compared with most existing assays, the new assay is more sensitive and specific, and completely eliminates the use of radioactive materials. Application of the new assay system can be widely expanded if new target genes and responding cell lines for other therapeutics are identified or engineered.
Type F botulism due to neurotoxigenic Clostridium baratii from an unknown source in an adult.
McCroskey, L M; Hatheway, C L; Woodruff, B A; Greenberg, J A; Jurgenson, P
1991-11-01
Type F botulism was confirmed in a 54-year-old male with signs compatible with botulism who reported to the emergency unit of a hospital. Botulinal neurotoxin was detected in the patient's serum and fecal specimens, and a neurotoxigenic organism whose physiologic characteristics correspond to those of Clostridium baratii was isolated. The toxin produced by the isolate was neutralized by type F botulinal antitoxin and cross-neutralized with lower efficiency by type E antitoxin. The patient's food history was not suggestive of botulism, and it seems likely that the illness was due to colonization of the gut.
Type F botulism due to neurotoxigenic Clostridium baratii from an unknown source in an adult.
McCroskey, L M; Hatheway, C L; Woodruff, B A; Greenberg, J A; Jurgenson, P
1991-01-01
Type F botulism was confirmed in a 54-year-old male with signs compatible with botulism who reported to the emergency unit of a hospital. Botulinal neurotoxin was detected in the patient's serum and fecal specimens, and a neurotoxigenic organism whose physiologic characteristics correspond to those of Clostridium baratii was isolated. The toxin produced by the isolate was neutralized by type F botulinal antitoxin and cross-neutralized with lower efficiency by type E antitoxin. The patient's food history was not suggestive of botulism, and it seems likely that the illness was due to colonization of the gut. PMID:1774272
Pilot scale production of highly efficacious and stable enterovirus 71 vaccine candidates.
Chou, Ai-Hsiang; Liu, Chia-Chyi; Chang, Cheng-Peng; Guo, Meng-Shin; Hsieh, Shih-Yang; Yang, Wen-Hsueh; Chao, Hsin-Ju; Wu, Chien-Long; Huang, Ju-Lan; Lee, Min-Shi; Hu, Alan Yung-Chi; Lin, Sue-Chen; Huang, Yu-Yun; Hu, Mei-Hua; Chow, Yen-Hung; Chiang, Jen-Ron; Chang, Jui-Yuan; Chong, Pele
2012-01-01
Enterovirus 71 (EV71) has caused several epidemics of hand, foot and mouth diseases (HFMD) in Asia and now is being recognized as an important neurotropic virus. Effective medications and prophylactic vaccine against EV71 infection are urgently needed. Based on the success of inactivated poliovirus vaccine, a prototype chemically inactivated EV71 vaccine candidate has been developed and currently in human phase 1 clinical trial. In this report, we present the development of a serum-free cell-based EV71 vaccine. The optimization at each step of the manufacturing process was investigated, characterized and quantified. In the up-stream process development, different commercially available cell culture media either containing serum or serum-free was screened for cell growth and virus yield using the roller-bottle technology. VP-SFM serum-free medium was selected based on the Vero cell growth profile and EV71 virus production. After the up-stream processes (virus harvest, diafiltration and concentration), a combination of gel-filtration liquid chromatography and/or sucrose-gradient ultracentrifugation down-stream purification processes were investigated at a pilot scale of 40 liters each. Although the combination of chromatography and sucrose-gradient ultracentrifugation produced extremely pure EV71 infectious virus particles, the overall yield of vaccine was 7-10% as determined by a VP2-based quantitative ELISA. Using chromatography as the downstream purification, the virus yield was 30-43%. To retain the integrity of virus neutralization epitopes and the stability of the vaccine product, the best virus inactivation was found to be 0.025% formalin-treatment at 37 °C for 3 to 6 days. Furthermore, the formalin-inactivated virion vaccine candidate was found to be stable for >18 months at 4 °C and a microgram of viral proteins formulated with alum adjuvant could induce strong virus-neutralizing antibody responses in mice, rats, rabbits, and non-human primates. These results provide valuable information supporting the current cell-based serum-free EV71 vaccine candidate going into human Phase I clinical trials.
Lipid peroxidation and antioxidant enzyme status in oral carcinoma patients.
Khanna, R; Thapa, P B; Khanna, H D; Khanna, S; Khanna, A K; Shukla, H S
2005-01-01
To measure the lipid peroxidation and endogenous antioxidant enzyme status in oral carcinoma and the protective role of exogenous antioxidants. 20 new cases of histologically proven oral squamous cell carcinoma, 20 of leukoplakia and 20 age and sex matched healthy conrols were included. Intra oral pH of patients and controlled were measured by quantitative litmus paper test and serum was analysed for malonialdehyde (MDA), super oxide bismutase (SOD), catalase and glutathione peroxidase (GP). Patients with leukoplakia were treated with exogenous antioxidants for 3 months and the same were reassessed. Oral pH of oral cancer patients was neutral (PH-7) but that of leukoplakia and controls were mildly acidic (6.64 and 6.58 respectively). Serum malonialdehyde levels were highest in oral cancer group. With antioxidant enzymes super oxide bismutase, catalase and glutathione peroxidase different pattern was noticed. Antioxidant enzymes remained almost the same (P > 0.005 each) in patients with leukoplakia after 3 months of vitamin A,C and E. but there was marginal increase in catalase level (P<0.05). This study shows the positive benefit of vitamin (A,C,E) and nutrition supplementation on the antioxidant enzyme defense system hence prevention of oral carcinogenesis in patients with leukoplakia.
Antibodies against mumps virus component proteins.
Matsubara, Keita; Iwata, Satoshi; Nakayama, Tetsuo
2012-08-01
The neutralization (NT) test is regarded as the most reliable method for detection of protective antibodies, but is labor-intensive and time consuming. Enzyme-linked immunosorbent assay (EIA) is frequently used in sero-epidemiological studies because of its simplicity and ease of use. In this study, immunofluorescent (IF) antibodies against nucleocapsid (N), fusion (F), and hemagglutinin-neuraminidase (HN) proteins were investigated in comparison with NT and EIA antibodies. The antibody against N protein was dominant in serum samples obtained from patients with a previous history of mumps infection. Titers of antibodies against F and HN proteins were very low. Many serum samples were positive for EIA but negative for NT, and no significant correlation was noted between NT and EIA antibodies. Among the three component proteins, correlation of EIA and IF antibodies with N protein was relatively good. After vaccination with mumps vaccine, EIA positivity was closely related to the IF antibodies against N protein, and after vaccination NT-positive sera became positive for IF antibodies against F and HN proteins. IF antibodies against F and HN proteins were considered to have a strong association with NT antibodies, and those against N protein were considered to have a strong association with EIA antibodies.
Casoni, F; Merelli, E; Bedin, R; Sola, P; Bertolotto, A; Faglioni, P
2004-01-01
Interferon beta (INFbeta) may induce the expression of several proteins, including neopterin, considered a biological marker of INFbeta activity. The aim of this study was to determine the serum neopterin concentration at the beginning of, and during, IFNbeta-1a therapy in relapsing-remitting multiple sclerosis (r-r MS) patients, and to look for a possible correlation between protein synthesis and the clinical course of the disease. Thirteen r-r MS patients were treated with INFbeta-1a (i.m. 6 MIU/week) for 2 years. Blood samples for neopterin determinations were taken daily over a period of 1 week at the end of each 6 months of therapy, and tested for neutralizing antibodies (NABs). Neopterin levels peaked 24-48 h post-injection and returned to baseline after 120 h. After 1 year of therapy, four patients dropped out of the study because of progression of the disease: in these subjects a significant decrement of neopterin was observed. Neopterin baseline values were not found to decrease over the 2 years of therapy, and neopterin may be considered to be a useful marker of responsiveness to IFNbeta.
A Therapeutic Uricase with Reduced Immunogenicity Risk and Improved Development Properties
Nyborg, Andrew C.; Ward, Chris; Zacco, Anna; Grinberg, Luba; Geoghegan, James C.; Bean, Ryan; Wendeler, Michaela; Bartnik, Frank; O’Connor, Ellen; Gruia, Flaviu; Iyer, Vidyashankara; Feng, Hui; Roy, Varnika; Berge, Mark; Miner, Jeffrey N.; Wilson, David M.; Zhou, Dongmei; Nicholson, Simone; Wilker, Clynn; Wu, Chi Y.; Wilson, Susan; Jermutus, Lutz; Wu, Herren; Owen, David A.; Osbourn, Jane; Coats, Steven; Baca, Manuel
2016-01-01
Humans and higher primates are unique in that they lack uricase, the enzyme capable of oxidizing uric acid. As a consequence of this enzyme deficiency, humans have high serum uric acid levels. In some people, uric acid levels rise above the solubility limit resulting in crystallization in joints, acute inflammation in response to those crystals causes severe pain; a condition known as gout. Treatment for severe gout includes injection of non-human uricase to reduce serum uric acid levels. Krystexxa® is a hyper-PEGylated pig-baboon chimeric uricase indicated for chronic refractory gout that induces an immunogenic response in 91% of treated patients, including infusion reactions (26%) and anaphylaxis (6.5%). These properties limit its use and effectiveness. An innovative approach has been used to develop a therapeutic uricase with improved properties such as: soluble expression, neutral pH solubility, high E. coli expression level, thermal stability, and excellent activity. More than 200 diverse uricase sequences were aligned to guide protein engineering and reduce putative sequence liabilities. A single uricase lead candidate was identified, which showed low potential for immunogenicity in >200 human donor samples selected to represent diverse HLA haplotypes. Cysteines were engineered into the lead sequence for site specific PEGylation and studies demonstrated >95% PEGylation efficiency. PEGylated uricase retains enzymatic activity in vitro at neutral pH, in human serum and in vivo (rats and canines) and has an extended half-life. In canines, an 85% reduction in serum uric acid levels was observed with a single subcutaneous injection. This PEGylated, non-immunogenic uricase has the potential to provide meaningful benefits to patients with gout. PMID:28002433
Buchholz, Ursula J; Cunningham, Coleen K; Muresan, Petronella; Gnanashanmugam, Devasena; Sato, Paul; Siberry, George K; Rexroad, Vivian; Valentine, Megan; Perlowski, Charlotte; Schappell, Elizabeth; Thumar, Bhagvinji; Luongo, Cindy; Barr, Emily; Aziz, Mariam; Yogev, Ram; Spector, Stephen A; Collins, Peter L; McFarland, Elizabeth J; Karron, Ruth A
2018-04-11
Respiratory syncytial virus (RSV) is the most important viral cause of severe respiratory illness in young children and lacks a vaccine. RSV cold-passage/stabilized 2 (RSVcps2) is a modification of a previously evaluated vaccine candidate in which 2 major attenuating mutations have been stabilized against deattenuation. RSV-seronegative 6-24-month-old children received an intranasal dose of 105.3 plaque-forming units (PFU) of RSVcps2 (n = 34) or placebo (n = 16) (International Maternal Pediatric Adolescent AIDS Clinical Trials protocol P1114 and companion protocol CIR285). RSV serum neutralizing antibody titers before and 56 days after vaccination, vaccine virus infectivity (defined as vaccine virus shedding detectable in nasal wash and/or a ≥4-fold rise in serum antibodies), reactogenicity, and genetic stability were assessed. During the following RSV transmission season, participants were monitored for respiratory illness, with serum antibody titers measured before and after the season. A total of 85% of vaccinees were infected with RSVcps2 (median peak titer, 0.5 log10 PFU/mL by culture and 2.9 log10 copies/mL by polymerase chain reaction analysis); 77% shed vaccine virus, and 59% developed a ≥4-fold rise in RSV-serum neutralizing antibody titers. Respiratory tract and/or febrile illness occurred at the same rate (50%) in the vaccine and placebo groups. Deattenuation was not detected at either of 2 stabilized mutation sites. RSVcps2 was well tolerated and moderately immunogenic and had increased genetic stability in 6-24-month-old RSV-seronegative children. NCT01852266 and NCT01968083.
Martin, Guillaume; Chapuis, Elodie; Goudet, Jérôme
2008-01-01
Neutrality tests in quantitative genetics provide a statistical framework for the detection of selection on polygenic traits in wild populations. However, the existing method based on comparisons of divergence at neutral markers and quantitative traits (Qst–Fst) suffers from several limitations that hinder a clear interpretation of the results with typical empirical designs. In this article, we propose a multivariate extension of this neutrality test based on empirical estimates of the among-populations (D) and within-populations (G) covariance matrices by MANOVA. A simple pattern is expected under neutrality: D = 2Fst/(1 − Fst)G, so that neutrality implies both proportionality of the two matrices and a specific value of the proportionality coefficient. This pattern is tested using Flury's framework for matrix comparison [common principal-component (CPC) analysis], a well-known tool in G matrix evolution studies. We show the importance of using a Bartlett adjustment of the test for the small sample sizes typically found in empirical studies. We propose a dual test: (i) that the proportionality coefficient is not different from its neutral expectation [2Fst/(1 − Fst)] and (ii) that the MANOVA estimates of mean square matrices between and among populations are proportional. These two tests combined provide a more stringent test for neutrality than the classic Qst–Fst comparison and avoid several statistical problems. Extensive simulations of realistic empirical designs suggest that these tests correctly detect the expected pattern under neutrality and have enough power to efficiently detect mild to strong selection (homogeneous, heterogeneous, or mixed) when it is occurring on a set of traits. This method also provides a rigorous and quantitative framework for disentangling the effects of different selection regimes and of drift on the evolution of the G matrix. We discuss practical requirements for the proper application of our test in empirical studies and potential extensions. PMID:18245845
Chakravarthy, B R; Wong, J; Durkin, J P
1995-10-01
Murine neuroblastoma cells, N1E-115, were induced to differentiate into neuron-like cells by serum deprivation for 18 h. As previous studies have shown that the suppression of protein kinase C (PKC) activity by selective inhibitors or neutralizing antibodies induces neuroblastoma cells to differentiate, we tested the hypothesis that serum deprivation may cause a rapid loss in membrane PKC activity that occurs well before the morphological changes that are characteristic of cell differentiation. A significant reduction in particulate (membrane) PKC activity was indeed observed within 3 h of serum withdrawal when enzyme activity was measured in intact native membranes by the recently described in vitro "direct" assay. This rapid reduction in enzyme activity was confirmed by the decreased phosphorylation of the MARCKS protein, an endogenous PKC-selective substrate, in intact cells. The decrease in membrane PKC activity occurred without any loss in the amount of membrane-associated enzyme, suggesting that some factor(s) resident in neuroblastoma membranes was suppressing PKC activity. Indeed, results indicate the presence of an endogenous inhibitor of PKC tightly associated with neuroblastoma membranes. This inhibitory activity increased in the membranes of cells subjected to serum deprivation, raising the possibility that it was likely responsible for the decline in membrane PKC activity in differentiating N1E-115 cells. Preliminary characterization indicated that the inhibitory activity is a protein and is localized mainly in the membrane fraction. Thus, these results demonstrate directly that endogenous inhibitor can regulate membrane-associated PKC activity in cells and thereby modulate PKC-related neuronal functions.
Emami, Niloufar Hedayati; Lafout, Farzaneh Mahmoudi; Mohammadghasemi, Fahimeh
2018-01-01
Objective(s): Melatonin, an important hormone secreted by the epiphysis, is a powerful anti-oxidant with a high potential to neutralize medical toxins. The goal of this study was to demonstrate the beneficial effect of melatonin on epididymal sperm and reproductive parameters in mice treated with acetylsalicylic acid (ASA). Materials and Methods: Male adult mice were divided into four treatment groups: control, ASA, melatonin, and ASA+melatonin. Mice were administered ASA (50 mg/kg, orally) and/or melatonin (10 mg/kg, intraperitoneally), or vehicle control, for 14 days. Sperm count, sperm motility, and sperm morphology were evaluated to assess fertility. A colorimetric assay was used to measure serum total antioxidant capacity (TAC). A sperm chromatin dispersion (SCD) test was used to assess sperm chromatin integrity. Sex hormone levels were measured by ELISA. Results: Compared to the control group, ASA treatment resulted in a significant decrease in sperm parameters (P<0.05), as well as a decrease in the integrity of sperm chromatin (P<0.01). ASA treatment also reduced serum testosterone and TAC levels (P<0.05). Co-administration of melatonin with ASA significantly improved epididymal sperm parameters and increased serum testosterone and TAC levels compared to the ASA-treated group. LH level was not different in the combined treatment group compared to control or ASA treatment. Conclusion: Short-term administration of ASA (50 mg/kg) has adverse effects on male reproductive function in mice. Co-administration of melatonin protects against ASA-induced impairment of male reproductive function by preventing the reduction in serum TAC and testosterone levels seen with ASA treatment alone. PMID:29456808
Mroz, Claudia; Gwida, Mayada; El-Ashker, Maged; El-Diasty, Mohamed; El-Beskawy, Mohamed; Ziegler, Ute; Eiden, Martin; Groschup, Martin H
2017-04-05
Rift Valley fever virus (RVFV) caused several outbreaks throughout the African continent and the Arabian Peninsula posing significant threat to human and animal health. In Egypt the first and most important Rift Valley fever epidemic occurred during 1977/78 with a multitude of infected humans and huge economic losses in livestock. After this major outbreak, RVF epidemics re-occurred in irregular intervals between 1993 and 2003. Seroprevalence of anti-RVFV antibodies in livestock during inter-epidemic periods can be used for supporting the evaluation of the present risk exposure for animal and public health. A serosurvey was conducted during 2014/2015 in non-vaccinated livestock including camels, sheep, goats and buffalos in different areas of the Nile River Delta as well as the furthermost southeast of Egypt to investigate the presence of anti-RVFV antibodies for further evaluating of the risk exposure for animal and human health. All animals integrated in this study were born after the last Egyptian RVF epidemic in 2003 and sampled buffalos and small ruminants were not imported from other endemic countries. A total of 873 serum samples from apparently healthy animals from different host species (camels: n = 221; sheep: n = 438; goats: n = 26; buffalo: n = 188) were tested serologically using RVFV competition ELISA, virus neutralization test and/or an indirect immunofluorescence assay, depending on available serum volume. Sera were assessed positive when virus neutralization test alone or least two assays produced consistent positive results. The overall seroprevalence was 2.29% (95%CI: 1.51-3.07) ranging from 0% in goats, 0.46% in sheep (95%CI: 0.41-0.5), and 3.17% in camels (95%CI: 0.86-5.48) up to 5.85% in buffalos (95%CI: 2.75-8.95). Our findings assume currently low level of circulating virus in the investigated areas and suggest minor indication for a new RVF epidemic. Further the results may indicate that during long inter-epidemic periods, maintenance of the virus occur in vectors and also most probably in buffaloes within cryptic cycle where sporadic, small and local epidemics may occur. Therefore, comprehensive and well-designed surveillance activities are urgently needed to detect first evidence for transition from endemic to epidemic cycle.
Equine Immunoglobulin and Equine Neutralizing F(ab')₂ Protect Mice from West Nile Virus Infection.
Cui, Jiannan; Zhao, Yongkun; Wang, Hualei; Qiu, Boning; Cao, Zengguo; Li, Qian; Zhang, Yanbo; Yan, Feihu; Jin, Hongli; Wang, Tiecheng; Sun, Weiyang; Feng, Na; Gao, Yuwei; Sun, Jing; Wang, Yanqun; Perlman, Stanley; Zhao, Jincun; Yang, Songtao; Xia, Xianzhu
2016-12-18
West Nile virus (WNV) is prevalent in Africa, Europe, the Middle East, West Asia, and North America, and causes epidemic encephalitis. To date, no effective therapy for WNV infection has been developed; therefore, there is urgent need to find an efficient method to prevent WNV disease. In this study, we prepared and evaluated the protective efficacy of immune serum IgG and pepsin-digested F(ab')₂ fragments from horses immunized with the WNV virus-like particles (VLP) expressing the WNV M and E proteins. Immune equine F(ab')₂ fragments and immune horse sera efficiently neutralized WNV infection in tissue culture. The passive transfer of equine immune antibodies significantly accelerated the virus clearance in the spleens and brains of WNV infected mice, and reduced mortality. Thus, equine immunoglobulin or equine neutralizing F(ab')₂ passive immunotherapy is a potential strategy for the prophylactic or therapeutic treatment of patients infected with WNV.
Watson, Rebecca E; Hafez, Ahmed M; Kremsky, Jonathan N; Bizzigotti, George O
2007-01-01
This paper reports the toxicity and environmental impact of neutralents produced from the hydrolysis of binary chemical agent precursor chemicals DF (methylphosphonic difluoride) and QL (2-[bis(1-methylethyl)amino]ethyl ethyl methylphosphonite). Following a literature review of the neutralent mixtures and constituents, basic toxicity tests were conducted to fill data gaps, including acute oral and dermal median lethal dose assays, the Ames mutagenicity test, and ecotoxicity tests. For methylphosphonic acid (MPA), a major constituent of DF neutralent, the acute oral LD(50) in the Sprague-Dawley rat was measured at 1888 mg/kg, and the Ames test using typical tester strains of Salmonella typhimurium and Escherichia coli was negative. The 48-h LC(50) values for pH-adjusted DF neutralent with Daphnia magna and Cyprinodon variegatus were > 2500 mg/L and 1593 mg/L, respectively. The acute oral LD(50) values in the rat for QL neutralent constituents methylphosphinic acid (MP) and 2-diisopropylaminoethanol (KB) were both determined to be 940 mg/kg, and the Ames test was negative for both. Good Laboratory Practice (GLP)-compliant ecotoxicity tests for MP and KB gave 48-h D. magna EC(50) values of 6.8 mg/L and 83 mg/L, respectively. GLP-compliant 96-h C. variegatus assays on MP and KB gave LC(50) values of 73 and 252 mg/L, respectively, and NOEC values of 22 and 108 mg/L. QL neutralent LD(50) values for acute oral and dermal toxicity tests were both > 5000 mg/kg, and the 48-h LD(50) values for D. magna and C. variegatus were 249 and 2500 mg/L, respectively. Using these data, the overall toxicity of the neutralents was assessed.
Paweska, J T
1997-06-01
Clinical, virological and serological responses were investigated in five pregnant donkey mares after experimental exposure to the South African asinine-94 strain of equine arteritis virus (EAV), and the duration of maternal immunity to EAV was studied in their foals. In four intranasally inoculated mares, fever with maximum rectal temperatures of 39.1-40.7 degrees C was recorded 2-11 d after challenge. All the inoculated mares developed mild depression, and a serous ocular and nasal discharge; in three mares mild conjuctivitis was observed. The virus was recovered from the nasopharynx and from buffy-coat samples of all the mares 3-10 d, and 2-18 d post inoculation (p.i.), respectively. Seroconversion to EAV was detected on days 8-10 p.i. Peak serum-virus-neutralizing antibody titres of log10 1.8-2.4, and IgG ELISA OD values of 0.85-2.15 were recorded 2-3 weeks p.i. The in-contact (p.c.) control mare developed fever on days 15-19 post exposure, and showed mild clinical signs of equine viral arteritis similar to those observed in the inoculated mares. Seroconversion to EAV was detected in the p.c. mare on day 20 post exposure, and virus was isolated from nasal swabs and blood samples collected at the time of the febrile response and 1-3 d afterwards. None of the mares aborted. After they had given normal birth 45-128 d p.i. or after p.c. exposure, no virus could be isolated from their placentas. The concentration of EAV-neutralizing antibody in colostrum was two to eight times higher than in serum samples collected at the time of parturition. All the foals born to infected mares were clinically normal at the time of birth and throughout the subsequent 1-2 months of observation. No EAV was recovered from the buffy-coat fraction of blood samples collected at birth nor from those collected on days 1, 2 and 7 after birth. Also, no virus-serum-neutralizing or IgG ELISA antibody to EAV was detected in sera collected immediately after birth before the foals started nursing. The colostrum-derived maternal antibodies against EAV gradually declined and could not be detected by either the VN test or ELISA for 2-3 months after birth. This study demonstrates that the asinine-94 strain of EAV does not cause abortion in pregnant donkey mares. Furthermore, no carrier state could be demonstrated in foals born to mares infected at the time of pregnancy.
Gómez, Sergio Y; Ocazionez, Raquel E
2008-01-01
Determining the frequency of yellow fever seroprotective antibody neutralising titres (YF-NT >or=1:10) in Colombians vaccinated with the 17 D virus and ascertaining the extent to which YF virus can be neutralised by dengue antibodies. Serum samples were taken from 100 subjects who showed their vaccination record and from 116 residents in municipalities (Norte de Santander) affected by a wild YF outbreak in 2002-2003 who were reported to have been YF vaccinated. Sera from individuals with (n=61) and without (n=16) dengue antibodies who had never been YF vaccinated were included. All the sera were tested by 75 % YF plaque-reduction neutralization test. YF-NT titres >or=1:10 were founded in 90 % of subjects with vaccination recorded with minors variations in relation to age. In contrast, there was correlation between decrease of seroprotective YF-NT titres frequency and increase of immunization time (r=0.95; p=0.04). In residents in YF endemic area, YF-NT titres >or= 1.10 were founded in 92,6 % adults and 69 % children. YF 17 D virus was neutralized (52-100 %) by dengue sera more efficiently than non-dengue immune sera (p<0.001). Individuals immunised with YF vaccine 17 D could not be protected against YF: up to 31% children and 10 % adults. Dengue antibodies inhibited YF virus and its significance in terms of YF protection must be investigated.
Liu, Jian; Ye, Xiangzhong; Jia, Jizong; Zhu, Rui; Wang, Lina; Chen, Chunye; Yang, Lianwei; Wang, Yongmei; Wang, Wei; Ye, Jianghui; Li, Yimin; Zhu, Hua; Zhao, Qinjian; Cheng, Tong; Xia, Ningshao
2016-01-01
Varicella-zoster virus (VZV) is a highly contagious agent of varicella and herpes zoster. Varicella can be lethal to immunocompromised patients, babies, HIV patients and other adults with impaired immunity. Serological evaluation of immunity to VZV will help determine which individuals are susceptible and evaluate vaccine effectiveness. A collection of 110 monoclonal antibodies (mAbs) were obtained by immunization of mice with membrane proteins or cell-free virus. The mAbs were well characterized, and a competitive sandwich ELISA (capture mAb: 8H6; labelling mAb: 1B11) was established to determine neutralizing antibodies in human serum with reference to the FAMA test. A total of 920 human sera were evaluated. The competitive sandwich ELISA showed a sensitivity of 95.6%, specificity of 99.77% and coincidence of 97.61% compared with the fluorescent-antibody-to-membrane-antigen (FAMA) test. The capture mAb 8H6 was characterized as a specific mAb for VZV ORF9, a membrane-associated tegument protein that interacts with glycoprotein E (gE), glycoprotein B (gB) and glycoprotein C (gC). The labelling mAb 1B11 was characterized as a complement-dependent neutralizing mAb specific for the immune-dominant epitope located on gE, not on other VZV glycoproteins. The established competitive sandwich ELISA could be used as a rapid and high-throughput method for evaluating immunity to VZV. PMID:26853741
Evidence of SV40 infections in hospitalized children
NASA Technical Reports Server (NTRS)
Butel, J. S.; Jafar, S.; Wong, C.; Arrington, A. S.; Opekun, A. R.; Finegold, M. J.; Adam, E.
1999-01-01
Simian virus 40 (SV40) is known to have contaminated poliovirus vaccines used between 1955 and 1963. Accumulating reports have described the presence of SV40 DNA in human tumors and normal tissues, although the significance of human infections by SV40 is unknown. We investigated whether unselected hospitalized children had evidence of SV40 infections and whether any clinical correlations were apparent. Serum samples were examined for SV40 neutralizing antibody using a specific plaque reduction test; of 337 samples tested, 20 (5.9%) had antibody to SV40. Seropositivity increased with age and was significantly associated with kidney transplants (6 of 15 [40%] positive, P < .001). Many of the antibody-positive patients had impaired immune systems. Molecular assays (polymerase chain reaction and DNA sequence analysis) on archival tissue specimens confirmed the presence of SV40 DNA in 4 of the antibody-positive patients. This study, using 2 independent assays, shows the presence of SV40 infections in children born after 1980. We conclude that SV40 causes natural infections in humans.
Noguchi, H
1907-07-17
In normal serums of the majority of mammalian and avian blood there exists certain substances capable of activating venom haemolysin. They are extractable from serum by means of ether, and are capable of conferring upon the originally non-activating serum a power to activate venom, when mixed with the latter. The ethereal extract consists of fatty acids, neutral fats and possibly also some ether soluble organic soaps. The fatty acids and soaps, especially of the oleinic series, acquire certain characteristics of complements in general, when they are mixed with serum. They are inactive without the venom in the mixture; they are inactivable with calcium chloride; they exhibit a tendency to go off in activity with age; they are inactive or only weakly active at 0 degrees C., and they are extractable by ether. In testing the serum from which the ether soluble substances are removed, it is found that no venom activating property is left. Warm alcoholic extraction of such serum yields, however, a large quantity of lecithin. In the case of non-activating serums no venom activating fats appear in the ethereal extract. Lecithin exists in such serum in no less quantity than in the activating kind. The addition of oleinic acid or its soluble soaps to a non-activating serum, in a ratio which corresponds to the percentage of fatty acids or soaps contained in some of the easily activating serums, will make the serum highly active in regard to venom. In normal serum of dog there exists, besides the group of activators already mentioned, another kind of venom activators which has been identified as a lecithin compound acting in the manner of free lecithin. A very sharp differentiation of the haemolysis produced by this activator and by the other groups of activators is obtained by means of calcium chloride, which is powerless against lecithin or lecithin compounds, but effective in removing the action of the latter. This lecithin containing proteid can be precipitated by half saturation with ammonium sulphate, but is perfectly soluble in water, and is not coagulated in neutral alkaline salt solutions upon boiling. Alcohol precipitates a proteid-like coagulum and extracts lecithin from it; ether does not extract lecithin from this compound. Non-activating serums do not contain any such lecithin compound. Lecithin contained in other serum proteids, mainly as lecithalbumin, and perhaps as contained in globulin, is not able to activate venom. This is true of all the serums with which I worked; it matters not whether these fractions (obtained with ammonium sulphate) belong to the most activating serum (dog) or to the non-activating serum (ox). The non-coagulable portion of all heated serum contains a venom activator of the nature of lecithin. This activator is contained in a non-coagulable proteid described by Howell which is identical with Chabrie's albumon. As there is no ether-extractable lecithin in this portion of the serum, the activating property of heated serum must be due to this proteid compound of lecithin. That this lecithin proteid does not pre-exist in normal serum but is produced by the action of high temperature is true of all serums except that of the dog. In venom activation we know now that lecithin becomes reactive with venom when it is transformed from other proteid compounds into the non-coagulable form, the albumon. Howell's view of the non-existence of the non-coagulable proteid in normal serum seems to receive a biological support from venom haemolysis. Ovovitellin derived from hen's egg is one of the best venom activators of the lecithin proteid type. The cause of venom susceptibility of various kinds of blood corpuscles does not depend upon the existence of lecithin in the corpuscles, but solely upon the amount of fatty acids, and perhaps, also, soaps and fats, contained in the corpuscles. The protection which calcium chloride gives against venom haemolysis is proof of the absence of lecithin activation. From the stroma of susceptible corpuscles fatty acids or some fats can be extracted with ether. After ethereal extraction the stroma becomes non-activating, while the extract contains fatty acids and some soaps or fats, which when added to venom-resistant corpuscles render the latter vulnerable to venom. The corpuscular solution of non-activating corpuscles does not contain enough fatty acids. The larger the amount of fatty acids and soaps in the corpuscles, the easier the cells undergo venom haemolysis. Lecithin exists in the strorna of all kinds of corpuscles, but in a form unavailable for venom activation. The somatic cytolytic processes caused by venom requires intracellular complements. The experiments performed on the cells of liver, kidney, testis and brain of the guinea-pig and rat indicate that the substances which act as complements are inactivable by calcium chloride.
VACCINATION AGAINST YELLOW FEVER WITH IMMUNE SERUM AND VIRUS FIXED FOR MICE
Sawyer, W. A.; Kitchen, S. F.; Lloyd, Wray
1932-01-01
1. After preliminary experiments in monkeys, 15 persons were actively immunized by a single injection of a dried mixture of living yellow fever virus, fixed for mice, and human immune serum, with separate injections of enough additional serum to make up the amount required for protection. 2. One person was similarly immunized by injecting immune serum and dried virus separately. 3. By titration of the sera of vaccinated persons in mice, it was shown that the immunity rose in a few weeks to a height comparable to that reached after an attack of yellow fever, and remained there throughout an observation period of 6 months. 4. Yellow fever virus could not be recovered from the blood of vaccinated persons or monkeys, except when the latter had received less than the minimal effective amount of immune serum. 5. Neutralization of yellow fever virus by immune serum took place very slowly in vitro at room temperature in our experiments, and could not have been an appreciable factor in vaccination with the serum virus mixtures. 6. A mixture of fixed virus and immune serum retained its immunizing power for 8 months when dried in the frozen state and sealed in glass. 7. It appears that the immunizing reaction after yellow fever vaccination was a part of a true infectious process, as was also the observed leucopenia. PMID:19870044
Study on camel IgG purification
Khamehchian, Sedigheh; Zolfagharian, Hossein; Dounighi, Naser Mohammadpour; Tebianian, Majid; Madani, Rasool
2014-01-01
A combined process of ammonium sulfate precipitation (salting out) and ion-exchange chromatography on DEAE-Sepharose CL-6B was used to prepare camel antivenom (IgG) against Naja Naja Oxiana for therapy. In the ammonium sulfate precipitation, the best condition for fractionation of IgG from the other proteins in camel serum was 55% precipitate. The camel IgG presented as 2 bands with molecular masses of 250 and 100 kDa, the latter corresponding to heavy chain IgG, on 10% gel electrophoresis. A trace amount of non-IgG proteins was not isolated and remained in this precipitate. Therefore in order to effectively separate albumin and the other nonspecific proteins from the IgG, the 25% precipitate of ammonium sulfate precipitation of serum was subjected to DEAE-Sepharose CL-6B column chromatography. A peak of antibody (IgG) could be obtained by elution with sodium phosphate buffer. In this stage, 2 bands of molecular masses of 150 and 75 kDa were observed on 7% gel electrophoresis. A comparative study was performed between camel IgG and conventional horse F(ab)2 antivenoms in term of potency (serum neutralization test and ELISA). Our results showed that the potency of camel antivenom was 4-fold higher than that of horse. It is suggested the combined ammonium sulfate precipitation and ion-exchange chromatography process effectively removed residual proteins in the final camel IgG preparation and can be a suitable method for large-scale refinement of therapeutic camel antivenoms. PMID:24642472
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.
Diotti, Roberta Antonia; Capra, Ruggero; Moiola, Lucia; Caputo, Valeria; De Rossi, Nicola; Sangalli, Francesca; Martinelli, Vittorio; Burioni, Roberto; Clementi, Massimo; Mancini, Nicasio
2016-05-07
The association between natalizumab and progressive multifocal leukoencephalopathy (PML) is established, but a reliable clinical risk stratification flow-chart is lacking. New risk factors are needed, such as the possible role of the anti-JC polyomavirus (JCPyV) neutralizing antibody. In this pilot study, we analyzed this parameter during natalizumab treatment. Sequential sera of 38 multiple sclerosis patients during their first year of natalizumab treatment were collected, and grouped according to the number of infusions. For 11 patients, samples were also available after 24 infusions (T24), when progressive multifocal leukoencephalopathy (PML) risk is higher. The reactivity against VP1, the main JCPyV surface protein, and the anti-JCPyV neutralizing activity were evaluated. During the first year, a lack of correlation between anti-JCPyV antibody response and its neutralizing activity was observed: a significant decrease in anti-JCPyV antibody response was observed (p = 0.0039), not paralleled by a similar trend in the total anti-JCPyV neutralizing activity (p = 0.2239). This lack of correlation was even more evident at T24 when, notwithstanding a significant increase in the anti-JCPyV response (p = 0.0097), a further decrease of the neutralizing activity was observed (p = 0.0062). This is the first study evidencing, prospectively, the lack of correlation between the anti-JCPyV antibody response and its neutralizing activity during natalizumab treatment.
Ji, Xin; Olinger, Gene G; Aris, Sheena; Chen, Ying; Gewurz, Henry; Spear, Gregory T
2005-09-01
Mannose-binding lectin (MBL), a serum lectin that mediates innate immune functions including activation of the lectin complement pathway, binds to carbohydrates expressed on some viral glycoproteins. In this study, the ability of MBL to bind to virus particles pseudotyped with Ebola and Marburg envelope glycoproteins was evaluated. Virus particles bearing either Ebola (Zaire strain) or Marburg (Musoke strain) envelope glycoproteins bound at significantly higher levels to immobilized MBL compared with virus particles pseudotyped with vesicular stomatitis virus glycoprotein or with no virus glycoprotein. As observed in previous studies, Ebola-pseudotyped virus bound to cells expressing the lectin DC-SIGN (dendritic cell-specific intercellular adhesion molecule 3-grabbing non-integrin). However, pre-incubation of virus with MBL blocked DC-SIGN-mediated binding to cells, suggesting that the two lectins bind at the same or overlapping sites on the Ebola glycoprotein. Neutralization experiments showed that virus pseudotyped with Ebola or Marburg (Musoke) glycoprotein was neutralized by complement, while the Marburg (Ravn strain) glycoprotein-pseudotyped virus was less sensitive to neutralization. Neutralization was partially mediated through the lectin complement pathway, since a complement source deficient in MBL was significantly less effective at neutralizing viruses pseudotyped with filovirus glycoproteins and addition of purified MBL to the MBL-deficient complement increased neutralization. These experiments demonstrated that MBL binds to filovirus envelope glycoproteins resulting in important biological effects and suggest that MBL can interact with filoviruses during infection in humans.
Mutation in West Nile Virus Structural Protein prM during Human Infection.
Lustig, Yaniv; Lanciotti, Robert S; Hindiyeh, Musa; Keller, Nathan; Milo, Ron; Mayan, Shlomo; Mendelson, Ella
2016-09-01
A mutation leading to substitution of a key amino acid in the prM protein of West Nile virus (WNV) occurred during persistent infection of an immunocompetent patient. WNV RNA persisted in the patient's urine and serum in the presence of low-level neutralizing antibodies. This case demonstrates active replication of WNV during persistent infection.
USDA-ARS?s Scientific Manuscript database
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...
Isolation of Ancestral Sylvatic Dengue Virus Type 1, Malaysia
Teoh, Boon-Teong; Sam, Sing-Sin; Abd-Jamil, Juraina
2010-01-01
Ancestral sylvatic dengue virus type 1, which was isolated from a monkey in 1972, was isolated from a patient with dengue fever in Malaysia. The virus is neutralized by serum of patients with endemic DENV-1 infection. Rare isolation of this virus suggests a limited spillover infection from an otherwise restricted sylvatic cycle. PMID:21029545
Tumor-associated erythrocytosis in a dog with nasal fibrosarcoma.
Couto, C G; Boudrieau, R J; Zanjani, E D
1989-01-01
Erythrocytosis (hematocrit, 79%) was diagnosed in an 8-year-old, neutered female, mixed-breed dog with an intranasal fibrosarcoma. Both serum and tumor erythropoietin (Ep) activities were elevated, as determined by the polycythemic exhypoxic mouse model, and the Ep activity was neutralized in that model by rabbit anti-Ep antibodies. Tumor resection normalized the hematocrit.
Association between Psychopathic Disorder and Serum Antibody to Herpes Simplex Virus (Type 1)
Cleobury, J. F.; Skinner, G. R. B.; Thouless, M. E.; Wildy, P.
1971-01-01
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. PMID:5543996
Association between psychopathic disorder and serum antibody to herpes simplex virus (type 1).
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.
Lipid droplet formation on opposing sides of the endoplasmic reticulum
Sturley, Stephen L.; Hussain, M. Mahmood
2012-01-01
In animal cells, the primary repositories of esterified fatty acids and alcohols (neutral lipids) are lipid droplets that form on the lumenal and/or cytoplasmic side of the endoplasmic reticulum (ER) membrane. A monolayer of amphipathic lipids, intermeshed with key proteins, serves to solubilize neutral lipids as they are synthesized and desorbed. In specialized cells, mobilization of the lipid cargo for delivery to other tissues occurs by secretion of lipoproteins into the plasma compartment. Serum lipoprotein assembly requires an obligate structural protein anchor (apolipoprotein B) and a dedicated chaperone, microsomal triglyceride transfer protein. By contrast, lipid droplets that form on the cytoplasmic face of the ER lack an obligate protein scaffold or any required chaperone/lipid transfer protein. Mobilization of neutral lipids from the cytosol requires regulated hydrolysis followed by transfer of the products to different organelles or export from cells. Several proteins play a key role in controlling droplet number, stability, and catabolism; however, it is our premise that their formation initiates spontaneously, solely as a consequence of neutral lipid synthesis. This default pathway directs droplets into the cytoplasm where they accumulate in many lipid disorders. PMID:22701043
Evaluation of candidate vaccine approaches for MERS-CoV
Wang, Lingshu; Shi, Wei; Joyce, M. Gordon; ...
2015-07-28
The emergence of Middle East respiratory syndrome coronavirus (MERS-CoV) as a cause of severe respiratory disease highlights the need for effective approaches to CoV vaccine development. Efforts focused solely on the receptor-binding domain (RBD) of the viral Spike (S) glycoprotein may not optimize neutralizing antibody (NAb) responses. Here we show that immunogens based on full-length S DNA and S1 subunit protein elicit robust serum-neutralizing activity against several MERS-CoV strains in mice and non-human primates. Serological analysis and isolation of murine monoclonal antibodies revealed that immunization elicits NAbs to RBD and, non-RBD portions of S1 and S2 subunit. Multiple neutralization mechanismsmore » were demonstrated by solving the atomic structure of a NAb-RBD complex, through sequencing of neutralization escape viruses and by constructing MERS-CoV S variants for serological assays. Immunization of rhesus macaques confers protection against MERS-CoV-induced radiographic pneumonia, as assessed using computerized tomography, supporting this strategy as a promising approach for MERS-CoV vaccine development.« less
Evaluation of candidate vaccine approaches for MERS-CoV
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Lingshu; Shi, Wei; Joyce, M. Gordon
The emergence of Middle East respiratory syndrome coronavirus (MERS-CoV) as a cause of severe respiratory disease highlights the need for effective approaches to CoV vaccine development. Efforts focused solely on the receptor-binding domain (RBD) of the viral Spike (S) glycoprotein may not optimize neutralizing antibody (NAb) responses. Here we show that immunogens based on full-length S DNA and S1 subunit protein elicit robust serum-neutralizing activity against several MERS-CoV strains in mice and non-human primates. Serological analysis and isolation of murine monoclonal antibodies revealed that immunization elicits NAbs to RBD and, non-RBD portions of S1 and S2 subunit. Multiple neutralization mechanismsmore » were demonstrated by solving the atomic structure of a NAb-RBD complex, through sequencing of neutralization escape viruses and by constructing MERS-CoV S variants for serological assays. Immunization of rhesus macaques confers protection against MERS-CoV-induced radiographic pneumonia, as assessed using computerized tomography, supporting this strategy as a promising approach for MERS-CoV vaccine development.« less
Abend, Johanna R; Changala, Marguerite; Sathe, Atul; Casey, Fergal; Kistler, Amy; Chandran, Sindhu; Howard, Abigail; Wojciechowski, David
2017-06-01
BK virus (BKV)-associated nephropathy is the second leading cause of graft loss in kidney transplant recipients. Due to the high prevalence of persistent infection with BKV in the general population, it is possible that either the transplant recipient or donor may act as the source of virus resulting in viruria and viremia. Although several studies suggest a correlation between donor-recipient serostatus and the development of BK viremia, specific risk factors for BKV-related complications in the transplant setting remain to be established. We retrospectively determined the pretransplant BKV neutralizing serostatus of 116 donors (D)-recipient (R) pairs using infectious BKV neutralization assays with representatives from the 4 major viral serotypes. The neutralizing serostatus of donors and recipients was then correlated with the incidence of BK viremia during the first year posttransplantation. There were no significant differences in baseline demographics or transplant data among the 4 neutralizing serostatus groups, with the exception of calculated panel-reactive antibody which was lowest in the D+/R- group. Recipients of kidneys from donors with significant serum neutralizing activity (D+) had elevated risk for BK viremia, regardless of recipient serostatus (D+ versus D-: odd ratio, 5.0; 95% confidence interval, 1.9-12.7]; P = 0.0008). Furthermore, donor-recipient pairs with D+/R- neutralizing serostatus had the greatest risk for BK viremia (odds ratio, 4.9; 95% confidence interval, 1.7-14.6; P = 0.004). Donor neutralizing serostatus correlates significantly with incidence of posttransplant BK viremia. Determination of donor-recipient neutralizing serostatus may be useful in assessing the risk of BKV infection in kidney transplant recipients.
Muñoz-Alía, Miguel Angel; Casasnovas, José M; Celma, María Luisa; Carabaña, Juan; Liton, Paloma B; Fernandez-Muñoz, Rafael
2017-05-15
Measles virus (MV) remains a leading cause of vaccine-preventable deaths in children. Protection against MV is associated with neutralizing antibodies that preferentially recognize the viral hemagglutinin (MV-H), and to a lesser extent, the fusion protein (MV-F). Although MV is serologically monotypic, 24 genotypes have been identified. Here we report three neutralization epitopes conserved in the more prevalent circulating MV genotypes, two located in the MV-H receptor binding site (RBS) (antigenic site III) and a third in MV-H/MV-F interphase (antigenic site Ia) which are essential for MV multiplication. In contrast, two MV-H neutralization epitopes, showed a genotype-specific neutralization escape due to a single amino acid change, that we mapped in the "noose" antigenic site, or an enhanced neutralization epitope (antigenic site IIa). The monoclonal antibody (mAb) neutralization potency correlated with its binding affinity and was mainly driven by kinetic dissociation rate (k off ). We developed an immunoassay for mAb binding to MV-H in its native hetero-oligomeric structure with MV-F on the surface of a MV productive steady-state persistently infected (p.i.) human cell lines, and a competitive-binding assay with serum from individuals with past infection by different MV genotypes. Binding assays revealed that a broad neutralization epitope, in RBS antigenic site, a genotype specific neutralization epitopes, in noose and IIa sites, were immunogenic in natural infection and vaccination and may elicit long-lasting humoral immunity that might contribute to explain MV immunogenic stability. These results support the design of improved measles vaccines, broad-spectrum prophylactic or therapeutic antibodies and MV-used in oncolytic therapies. Copyright © 2017 Elsevier B.V. All rights reserved.
Fine epitope signature of antibody neutralization breadth at the HIV-1 envelope CD4-binding site.
Cheng, Hao D; Grimm, Sebastian K; Gilman, Morgan Sa; Gwom, Luc Christian; Sok, Devin; Sundling, Christopher; Donofrio, Gina; Hedestam, Gunilla B Karlsson; Bonsignori, Mattia; Haynes, Barton F; Lahey, Timothy P; Maro, Isaac; von Reyn, C Fordham; Gorny, Miroslaw K; Zolla-Pazner, Susan; Walker, Bruce D; Alter, Galit; Burton, Dennis R; Robb, Merlin L; Krebs, Shelly J; Seaman, Michael S; Bailey-Kellogg, Chris; Ackerman, Margaret E
2018-03-08
Major advances in donor identification, antigen probe design, and experimental methods to clone pathogen-specific antibodies have led to an exponential growth in the number of newly characterized broadly neutralizing antibodies (bnAbs) that recognize the HIV-1 envelope glycoprotein. Characterization of these bnAbs has defined new epitopes and novel modes of recognition that can result in potent neutralization of HIV-1. However, the translation of envelope recognition profiles in biophysical assays into an understanding of in vivo activity has lagged behind, and identification of subjects and mAbs with potent antiviral activity has remained reliant on empirical evaluation of neutralization potency and breadth. To begin to address this discrepancy between recombinant protein recognition and virus neutralization, we studied the fine epitope specificity of a panel of CD4-binding site (CD4bs) antibodies to define the molecular recognition features of functionally potent humoral responses targeting the HIV-1 envelope site bound by CD4. Whereas previous studies have used neutralization data and machine-learning methods to provide epitope maps, here, this approach was reversed, demonstrating that simple binding assays of fine epitope specificity can prospectively identify broadly neutralizing CD4bs-specific mAbs. Building on this result, we show that epitope mapping and prediction of neutralization breadth can also be accomplished in the assessment of polyclonal serum responses. Thus, this study identifies a set of CD4bs bnAb signature amino acid residues and demonstrates that sensitivity to mutations at signature positions is sufficient to predict neutralization breadth of polyclonal sera with a high degree of accuracy across cohorts and across clades.
Transmissible gastroenteritis virus: plaques and a plaque neutralization test.
Thomas, F C; Dulac, G C
1976-01-01
A plaquing system and plaque neutralization test in porcine thyroid cells were used to study different transmissible gastroenteritis isolates and hemagglutinating encephalomyelitis virus. Among transmissible gastroenteritis virus isolates, plaque size varied considerably and mixed size ranges sometimes occurred. The most recently isolated viruses produced smaller plaques than the laboratory viruses or hemagglutinating encephalomyelitis virus. All transmissible gastroenteritis virus isolates reacted in the plaque neutralization test with a transmissible gastroenteritis virus antiserum which showed no activity against hemagglutinating encephalomyelitis virus. Plaque neutralization results both from experimentally infected pigs and following a field outbreak demonstrated the reliability of this test and its greater sensitivity than the conventional tube test. Images Fig. 1. PMID:187296
Jarmer, Johanna; Zlatkovic, Jürgen; Tsouchnikas, Georgios; Vratskikh, Oksana; Strauß, Judith; Aberle, Judith H.; Chmelik, Vaclav; Kundi, Michael; Stiasny, Karin
2014-01-01
ABSTRACT Tick-borne encephalitis (TBE) virus is an important human-pathogenic flavivirus endemic in large parts of Europe and Central and Eastern Asia. Neutralizing antibodies specific for the viral envelope protein E are believed to mediate long-lasting protection after natural infection and vaccination. To study the specificity and individual variation of human antibody responses, we developed immunoassays with recombinant antigens representing viral surface protein domains and domain combinations. These allowed us to dissect and quantify antibody populations of different fine specificities in sera of TBE patients and vaccinees. Postinfection and postvaccination sera both displayed strong individual variation of antibody titers as well as the relative proportions of antibodies to different domains of E, indicating that the immunodominance patterns observed were strongly influenced by individual-specific factors. The contributions of these antibody populations to virus neutralization were quantified by serum depletion analyses and revealed a significantly biased pattern. Antibodies to domain III, in contrast to what was found in mouse immunization studies with TBE and other flaviviruses, did not play any role in the human neutralizing antibody response, which was dominated by antibodies to domains I and II. Importantly, most of the neutralizing activity could be depleted from sera by a dimeric soluble form of the E protein, which is the building block of the icosahedral herringbone-like shell of flaviviruses, suggesting that antibodies to more complex quaternary epitopes involving residues from adjacent dimers play only a minor role in the total response to natural infection and vaccination in humans. IMPORTANCE Tick-borne encephalitis (TBE) virus is a close relative of yellow fever, dengue, Japanese encephalitis, and West Nile viruses and distributed in large parts of Europe and Central and Eastern Asia. Antibodies to the viral envelope protein E prevent viral attachment and entry into cells and thus mediate virus neutralization and protection from disease. However, the fine specificity and individual variation of neutralizing antibody responses are currently not known. We have therefore developed new in vitro assays for dissecting the antibody populations present in blood serum and determining their contribution to virus neutralization. In our analysis of human postinfection and postvaccination sera, we found an extensive variation of the antibody populations present in sera, indicating substantial influences of individual-specific factors that control the specificity of the antibody response. Our study provides new insights into the immune response to an important human pathogen that is of relevance for the design of novel vaccines. PMID:25253341
Jarmer, Johanna; Zlatkovic, Jürgen; Tsouchnikas, Georgios; Vratskikh, Oksana; Strauß, Judith; Aberle, Judith H; Chmelik, Vaclav; Kundi, Michael; Stiasny, Karin; Heinz, Franz X
2014-12-01
Tick-borne encephalitis (TBE) virus is an important human-pathogenic flavivirus endemic in large parts of Europe and Central and Eastern Asia. Neutralizing antibodies specific for the viral envelope protein E are believed to mediate long-lasting protection after natural infection and vaccination. To study the specificity and individual variation of human antibody responses, we developed immunoassays with recombinant antigens representing viral surface protein domains and domain combinations. These allowed us to dissect and quantify antibody populations of different fine specificities in sera of TBE patients and vaccinees. Postinfection and postvaccination sera both displayed strong individual variation of antibody titers as well as the relative proportions of antibodies to different domains of E, indicating that the immunodominance patterns observed were strongly influenced by individual-specific factors. The contributions of these antibody populations to virus neutralization were quantified by serum depletion analyses and revealed a significantly biased pattern. Antibodies to domain III, in contrast to what was found in mouse immunization studies with TBE and other flaviviruses, did not play any role in the human neutralizing antibody response, which was dominated by antibodies to domains I and II. Importantly, most of the neutralizing activity could be depleted from sera by a dimeric soluble form of the E protein, which is the building block of the icosahedral herringbone-like shell of flaviviruses, suggesting that antibodies to more complex quaternary epitopes involving residues from adjacent dimers play only a minor role in the total response to natural infection and vaccination in humans. Tick-borne encephalitis (TBE) virus is a close relative of yellow fever, dengue, Japanese encephalitis, and West Nile viruses and distributed in large parts of Europe and Central and Eastern Asia. Antibodies to the viral envelope protein E prevent viral attachment and entry into cells and thus mediate virus neutralization and protection from disease. However, the fine specificity and individual variation of neutralizing antibody responses are currently not known. We have therefore developed new in vitro assays for dissecting the antibody populations present in blood serum and determining their contribution to virus neutralization. In our analysis of human postinfection and postvaccination sera, we found an extensive variation of the antibody populations present in sera, indicating substantial influences of individual-specific factors that control the specificity of the antibody response. Our study provides new insights into the immune response to an important human pathogen that is of relevance for the design of novel vaccines. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
Agnihothram, Sudhakar; Gopal, Robin; Yount, Boyd L.; Donaldson, Eric F.; Menachery, Vineet D.; Graham, Rachel L.; Scobey, Trevor D.; Gralinski, Lisa E.; Denison, Mark R.; Zambon, Maria; Baric, Ralph S.
2014-01-01
Background. Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in 2012, causing severe acute respiratory disease and pneumonia, with 44% mortality among 136 cases to date. Design of vaccines to limit the virus spread or diagnostic tests to track newly emerging strains requires knowledge of antigenic and serologic relationships between MERS-CoV and other CoVs. Methods. Using synthetic genomics and Venezuelan equine encephalitis virus replicons (VRPs) expressing spike and nucleocapsid proteins from MERS-CoV and other human and bat CoVs, we characterize the antigenic responses (using Western blot and enzyme-linked immunosorbent assay) and serologic responses (using neutralization assays) against 2 MERS-CoV isolates in comparison with those of other human and bat CoVs. Results. Serologic and neutralization responses against the spike glycoprotein were primarily strain specific, with a very low level of cross-reactivity within or across subgroups. CoV N proteins within but not across subgroups share cross-reactive epitopes with MERS-CoV isolates. Our findings were validated using a convalescent-phase serum specimen from a patient infected with MERS-CoV (NA 01) and human antiserum against SARS-CoV, human CoV NL63, and human CoV OC43. Conclusions. Vaccine design for emerging CoVs should involve chimeric spike protein containing neutralizing epitopes from multiple virus strains across subgroups to reduce immune pathology, and a diagnostic platform should include a panel of nucleocapsid and spike proteins from phylogenetically distinct CoVs. PMID:24253287
Chijimatsu, Takeshi; Umeki, Miki; Okuda, Yuji; Yamada, Koji; Oda, Hiroaki; Mochizuki, Satoshi
2011-02-01
We investigated whether the fat and protein fractions of freshwater clam (Corbicula fluminea) extract (FCE) could ameliorate hypercholesterolaemia in rats fed a high-cholesterol diet. We also explored the mechanism and the components that exert the hypocholesterolaemic effect of FCE. The doses of the fat and protein fractions were equivalent to those in 30 % FCE. The fat and protein fractions of FCE, two major components of FCE, significantly reduced the serum and hepatic cholesterol levels. The fat fraction more strongly reduced serum cholesterol levels than the same level of total FCE. The excretion of faecal neutral sterols increased in rats fed the total the FCE and the fat fraction of FCE. On the other hand, faecal bile acid levels were greater in rats fed the total FCE and the fat and protein fractions of FCE than in control animals. The hepatic gene expression of ATP-binding cassette transporter G5 and cholesterol 7α-hydroxylase was up-regulated by the administration of the total FCE and both the fat and protein fractions of FCE. These results showed that the fat and protein fractions of FCE had hypocholesterolaemic properties, and that these effects were greater with the fat fraction than with the protein fraction. The present study indicates that FCE exerts its hypocholesterolaemic effects through at least two different mechanisms, including enhanced excretion of neutral sterols and up-regulated biosynthesis of bile acids.
Mareze, Vania Aparecida; Borio, Cristina Silvia; Bilen, Marcos F; Fleith, Renata; Mirazo, Santiago; Mansur, Daniel Santos; Arbiza, Juan; Lozano, Mario Enrique; Bruña-Romero, Oscar
2016-01-01
Two new vaccine candidates against dengue virus (DENV) infection were generated by fusing the coding sequences of the self-budding Z protein from Junin virus (Z-JUNV) to those of two cryptic peptides (Z/DENV-P1 and Z/DENV-P2) conserved on the envelope protein of all serotypes of DENV. The capacity of these chimeras to generate virus-like particles (VLPs) and to induce virus-neutralizing antibodies in mice was determined. First, recombinant proteins that displayed reactivity with a Z-JUNV-specific serum by immunofluorescence were detected in HEK-293 cells transfected with each of the two plasmids and VLP formation was also observed by transmission electron microscopy. Next, we determined the presence of antibodies against the envelope peptides of DENV in the sera of immunized C57BL/6 mice. Results showed that those animals that received Z/DENV-P2 DNA coding sequences followed by a boost with DENV-P2 synthetic peptides elicited significant specific antibody titers (≥6.400). Finally, DENV plaque-reduction neutralization tests (PRNT) were performed. Although no significant protective effect was observed when using sera of Z/DENV-P1-immunized animals, antibodies raised against vaccine candidate Z/DENV-P2 (diluted 1:320) were able to reduce in over 50 % the number of viral plaques generated by infectious DENV particles. This reduction was comparable to that of the 4G2 DENV-specific monoclonal cross-reactive (all serotypes) neutralizing antibody. We conclude that Z-JUNV-VLP is a valid carrier to induce antibody-mediated immune responses in mice and that Z/DENV-P2 is not only immunogenic but also protective in vitro against infection of cells with DENV, deserving further studies. On the other side, DENV's fusion peptide-derived chimera Z/DENV-P1 did not display similar protective properties.
Samoylov, Alexandre; Cochran, Anna; Schemera, Bettina; Kutzler, Michelle; Donovan, Caitlin; Petrenko, Valery; Bartol, Frank; Samoylova, Tatiana
2015-12-20
Phage display is based on genetic engineering of phage coat proteins resulting in fusion peptides displayed on the surface of phage particles. The technology is widely used for generation of phages with novel characteristics for numerous applications in biomedicine and far beyond. The focus of this study was on development of phage-peptide constructs that stimulate production of antibodies against gonadotropin releasing hormone (GnRH). Phage-peptide constructs that elicit production of neutralizing GnRH antibodies can be used for anti-fertility and anti-cancer applications. Phage-GnRH constructs were generated via selection from a phage display library using several types of GnRH antibodies as selection targets. Such phage constructs were characterized for sequence similarities to GnRH peptide and frequency of their occurrence in the selection rounds. Five of the constructs with suitable characteristics were tested in mice as a single dose 5×10(11) virions (vir) vaccine and were found to be able to stimulate production of GnRH-specific antibodies, but not to suppress testosterone (indirect indicator of GnRH antibody neutralizing properties). Next, one of the constructs was tested at a higher dose of 2×10(12) vir per mouse in combination with a poly(lactide-co-glycolide) (PLGA)-based adjuvant. This resulted in multifold increase in GnRH antibody production and significant reduction of serum testosterone, indicating that antibodies produced in response to the phage-GnRH immunization possess neutralizing properties. To achieve optimal immune responses for desired applications, phage-GnRH constructs can be modified with respect to flanking sequences of GnRH-like peptides displayed on phage. Anticipated therapeutic effects also might be attained using optimized phage doses, a combination of several constructs in a single treatment, or application of adjuvants and advanced phage delivery systems. Copyright © 2015 Elsevier B.V. All rights reserved.
Morales, María A; Fabbri, Cintia M; Zunino, Gabriel E; Kowalewski, Martín M; Luppo, Victoria C; Enría, Delia A; Levis, Silvana C; Calderón, Gladys E
2017-02-01
Several medically important mosquito-borne flaviviruses have been detected in Argentina in recent years: Dengue (DENV), St. Louis encephalitis (SLEV), West Nile (WNV) and Yellow Fever (YFV) viruses. Evidence of Bussuquara virus (BSQV) and Ilheus virus (ILHV) activity were found, but they have not been associated with human disease. Non-human primates can act as important hosts in the natural cycle of flaviviruses and serological studies can lead to improved understanding of virus circulation dynamics and host susceptibility. From July-August 2010, we conducted serological and molecular surveys in free-ranging black howlers (Alouatta caraya) captured in northeastern Argentina. We used 90% plaque-reduction neutralization tests (PRNT90) to analyze 108 serum samples for antibodies to WNV, SLEV, YFV, DENV (serotypes 1and 3), ILHV, and BSQV. Virus genome detection was performed using generic reverse transcription (RT)-nested PCR to identify flaviviruses in 51 antibody-negative animals. Seventy animals had antibodies for one or more flaviviruses for a total antibody prevalence of 64.8% (70/108). Monotypic (13/70, 19%) and heterotypic (27/70, 39%) patterns were differentiated. Specific neutralizing antibodies against WNV, SLEV, DENV-1, DENV-3, ILHV, and BSQV were found. Unexpectedly, the highest flavivirus antibody prevalence detected was to WNV with 9 (8.33%) monotypic responses. All samples tested by (RT)-nested PCR were negative for viral genome. This is the first detection of WNV-specific antibodies in black howlers from Argentina and the first report in free-ranging non-human primates from Latin-American countries. Given that no animals had specific neutralizing antibodies to YFV, our results suggest that the study population remains susceptible to YFV. Monitoring of these agents should be strengthened to detect the establishment of sylvatic cycles of flaviviruses in America and evaluate risks to wildlife and human health.
Cerdà-Cuéllar, Marta; Lecollinet, Sylvie; Pearce-Duvet, Jessica; Busquets, Núria; García-Bocanegra, Ignacio; Pagès, Nonito; Vittecoq, Marion; Hammouda, Abdessalem; Samraoui, Boudjéma; Garnier, Romain; Ramos, Raül; Selmi, Slaheddine; González-Solís, Jacob; Jourdain, Elsa; Boulinier, Thierry
2014-01-01
In recent years, a number of zoonotic flaviviruses have emerged worldwide, and wild birds serve as their major reservoirs. Epidemiological surveys of bird populations at various geographical scales can clarify key aspects of the eco-epidemiology of these viruses. In this study, we aimed at exploring the presence of flaviviruses in the western Mediterranean by sampling breeding populations of the yellow-legged gull (Larus michahellis), a widely distributed, anthropophilic, and abundant seabird species. For 3 years, we sampled eggs from 19 breeding colonies in Spain, France, Algeria, and Tunisia. First, ELISAs were used to determine if the eggs contained antibodies against flaviviruses. Second, neutralization assays were used to identify the specific flaviviruses present. Finally, for colonies in which ELISA-positive eggs had been found, chick serum samples and potential vectors, culicid mosquitoes and soft ticks (Ornithodoros maritimus), were collected and analyzed using serology and PCR, respectively. The prevalence of flavivirus-specific antibodies in eggs was highly spatially heterogeneous. In northeastern Spain, on the Medes Islands and in the nearby village of L'Escala, 56% of eggs had antibodies against the flavivirus envelope protein, but were negative for neutralizing antibodies against three common flaviviruses: West Nile, Usutu, and tick-borne encephalitis viruses. Furthermore, little evidence of past flavivirus exposure was obtained for the other colonies. A subset of the Ornithodoros ticks from Medes screened for flaviviral RNA tested positive for a virus whose NS5 gene was 95% similar to that of Meaban virus, a flavivirus previously isolated from ticks of Larus argentatus in western France. All ELISA-positive samples subsequently tested positive for Meaban virus neutralizing antibodies. This study shows that gulls in the western Mediterranean Basin are exposed to a tick-borne Meaban-like virus, which underscores the need of exploring the spatial and temporal distribution of this flavivirus as well as its potential pathogenicity for animals and humans. PMID:24625959
Dedecjus, Marek; Masson, David; Gautier, Thomas; de Barros, Jean-Paul Pais; Gambert, Philippe; Lewinski, Andrzej; Adamczewski, Zbigniew; Moulin, Philippe; Lagrost, Laurent
2003-05-01
Hypothyroidism is associated with a number of abnormalities in lipoprotein metabolism. Although alterations in neutral lipid exchanges among plasma lipoproteins might be one characteristic feature of hypothyroidism, a few human studies of cholesteryl ester transfer protein (CETP) activity have led to heterogeneous and fragmentary observations. The aim of the present study was to analyse the influence of short-term hypothyroidism on CETP activity, as well as on the structure and composition of lipoproteins. PATIENTS, DESIGN AND MEASUREMENTS: Sixty-six thyroidectomized patients were withdrawn from L-thyroxine (L-T4) treatment for 5 weeks. Subsequently, L-T4 therapy was reinstated for 2 months and patients were compared to 61 matched normolipidaemic controls. Serum CETP activity and mass concentration, serum lipids, apolipoproteins and lipoprotein size distribution were determined in the three groups. Serum CETP mass concentration was significantly decreased in short-term hypothyroid patients, as compared to control subjects (3.22 +/- 0.98 vs. 3.79 +/- 1.2 mg/l, respectively; P < 0.001), and the values were normalized during L-T4 therapy. The ability of endogenous serum lipoproteins to interact with CETP was normal in short-term hypothyroid patients. Concordant observations were made regardless of whether neutral lipid transfers were measured from high-density lipoproteins (HDL) toward apo B-containing lipoproteins or from liposomes toward HDL. The size distribution of HDL was significantly different in short-term hypothyroid patients, compared to either the control or treated subgroups, with significant higher proportions of large-sized HDL2b and HDL2a (HDL2b: 13.6 +/- 6.5% before vs. 8.5 +/- 4.2% during L-T4 therapy, P < 0.05; HDL2a, 33.0 +/- 7.0% before vs. 29.3 +/- 6.9% during L-T4 therapy, P < 0.05). Although serum CETP mass concentration correlated negatively with the HDL2 to HDL3 ratio in control subjects (r = -0.588; P < 0.0001), no significant correlations were observed in hypothyroid patients, regardless of whether they were treated or not. Similarly, whereas the previously recognized positive correlation of CETP mass concentration with serum LDL cholesterol levels was found in control subjects (r = 0.264; P < 0.05), no significant correlations appeared in treated and untreated patients. Short-term hypothyroidism may constitute an unique situation in which concomitant alterations in serum cholesteryl ester transfer protein concentration and lipoprotein parameters are disconnected.
Anti-hepatoma activity in mice of a polysaccharide from the rhizome of Anemone raddeana.
Liu, Yang; Li, Yiming; Yang, Wenbin; Zhang, Li; Cao, Gang
2012-04-01
A neutral polysaccharide fraction (ARP) prepared from the rhizome of Anemone raddeana was tested for its anticancer activity in H22 tumor-bearing mice by oral administration. ARP could not only significantly inhibit the growth of H22 transplantable tumor, but also remarkably promote splenocytes proliferation, NK cell and CTL activity, as well as serum IL-2 and TNF-α production in tumor-bearing mice. In addition, ARP treatment to tumor bearing mice had no toxicity to body weight, the liver and kidney. Moreover it could reverse the hematological parameters induced by 5-fluorouracil (5-FU) to near normal. The above results suggested that the antitumor activity of ARP might be achieved by improving immune response, and they could act as antitumor agent with immunomodulatory activity. Copyright © 2012 Elsevier B.V. All rights reserved.
Intradermal inactivated poliovirus vaccine: a preclinical dose-finding study.
Kouiavskaia, Diana; Mirochnitchenko, Olga; Dragunsky, Eugenia; Kochba, Efrat; Levin, Yotam; Troy, Stephanie; Chumakov, Konstantin
2015-05-01
Intradermal delivery of vaccines has been shown to result in dose sparing. We tested the ability of fractional doses of inactivated poliovirus vaccine (IPV) delivered intradermally to induce levels of serum poliovirus-neutralizing antibodies similar to immunization through the intramuscular route. Immunogenicity of fractional doses of IPV was studied by comparing intramuscular and intradermal immunization of Wistar rats using NanoPass MicronJet600 microneedles. Intradermal delivery of partial vaccine doses induced antibodies at titers comparable to those after immunization with full human dose delivered intramuscularly. The results suggest that intradermal delivery of IPV may lead to dose-sparing effect and reduction of the vaccination cost. Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Ssemwanga, Deogratius; Doria-Rose, Nicole A; Redd, Andrew D; Shiakolas, Andrea R; Longosz, Andrew F; Nsubuga, Rebecca N; Mayanja, Billy N; Asiki, Gershim; Seeley, Janet; Kamali, Anatoli; Ransier, Amy; Darko, Samuel; Walker, Michael P; Bruno, Daniel; Martens, Craig; Douek, Daniel; Porcella, Stephen F; Quinn, Thomas C; Mascola, John R; Kaleebu, Pontiano
2018-04-23
This report describes the identification of a genetically confirmed linked heterosexual human immunodeficiency virus (HIV) superinfection (HIV-SI) in a woman with chronic HIV infection who acquired a second strain of the virus from her husband. Serum neutralizing antibody (NAb) responses against their homologous and heterologous viruses, including the superinfecting strain, in the woman and her husband were examined before and after onset of HIV-SI. The woman displayed a moderately potent and broad anti-HIV NAb response prior to superinfection but did not possess NAb activity against the superinfecting strain. This case highlights the unique potential of linked HIV-SI studies to examine natural protection from HIV infection.
Capillary Electrophoresis of Mono- and Oligosaccharides.
Toppazzini, Mila; Coslovi, Anna; Rossi, Marco; Flamigni, Anna; Baiutti, Edi; Campa, Cristiana
2016-01-01
This chapter reports an overview of the recent advances in the analysis of mono- and oligosaccharides by capillary electrophoresis (CE); furthermore, relevant reviews and research articles recently published in the field are tabulated. Additionally, pretreatments and procedures applied to uncharged and acidic carbohydrates (i.e., monosaccharides and lower oligosaccharides carrying carboxylate, sulfate, or phosphate groups) are described.Representative examples of such procedures are reported in detail, upon describing robust methodologies for the study of (1) neutral oligosaccharides derivatized by reductive amination and by formation of glycosylamines; (2) sialic acid derivatized with 2-aminoacridone, released from human serum immunoglobulin G; (3) anomeric couples of neutral glycosides separated using borate-based buffers; (4) unsaturated, underivatized oligosaccharides from lyase-treated alginate.
Lopez-Gordo, Estrella; Doszpoly, Andor; Duffy, Margaret R.; Coughlan, Lynda; Bradshaw, Angela C.; White, Katie M.; Denby, Laura; Nicklin, Stuart A.
2017-01-01
ABSTRACT Human adenoviral serotype 5 (HAdV-5) vectors have predominantly hepatic tropism when delivered intravascularly, resulting in immune activation and toxicity. Coagulation factor X (FX) binding to HAdV-5 mediates liver transduction and provides protection from virion neutralization in mice. FX is dispensable for liver transduction in mice lacking IgM antibodies or complement, suggesting that alternative transduction pathways exist. To identify novel factor(s) mediating HAdV-5 FX-independent entry, we investigated HAdV-5 transduction in vitro in the presence of serum from immunocompetent C57BL/6 or immunocompromised mice lacking IgM antibodies (Rag 2−/− and NOD-scid-gamma [NSG]). Sera from all three mouse strains enhanced HAdV-5 transduction of A549 cells. While inhibition of HAdV-5–FX interaction with FX-binding protein (X-bp) inhibited transduction in the presence of C57BL/6 serum, it had negligible effect on the enhanced transduction observed in the presence of Rag 2−/− or NSG serum. Rag 2−/− serum also enhanced transduction of the FX binding-deficient HAdV-5HVR5*HVR7*E451Q (AdT*). Interestingly, Rag 2−/− serum enhanced HAdV-5 transduction in a FX-independent manner in CHO-CAR and SKOV3-CAR cells (CHO or SKOV3 cells transfected to stably express human coxsackievirus and adenovirus receptor [CAR]). Additionally, blockade of CAR with soluble HAdV-5 fiber knob inhibited mouse serum-enhanced transduction in A549 cells, suggesting a potential role for CAR. Transduction of HAdV-5 KO1 and HAdV-5/F35 (CAR binding deficient) in the presence of Rag 2−/− serum was equivalent to that of HAdV-5, indicating that direct interaction between HAdV-5 and CAR is not required. These data suggest that FX may protect HAdV-5 from neutralization but has minimal contribution to HAdV-5 transduction in the presence of immunocompromised mouse serum. Alternatively, transduction occurs via an unidentified mouse serum protein capable of bridging HAdV-5 to CAR. IMPORTANCE The intravascular administration of HAdV-5 vectors can result in acute liver toxicity, transaminitis, thrombocytopenia, and injury to the vascular endothelium, illustrating challenges yet to overcome for HAdV-5-mediated systemic gene therapy. The finding that CAR and potentially an unidentified factor present in mouse serum might be important mediators of HAdV-5 transduction highlights that a better understanding of the complex biology defining the interplay between adenovirus immune recognition and cellular uptake mechanisms is still required. These findings are important to inform future optimization and development of HAdV-5-based adenoviral vectors for gene therapy. PMID:28381574
Konduru, Krishnamurthy; Shurtleff, Amy C; Bavari, Sina; Kaplan, Gerardo
2018-04-01
Ebola virus (EBOV), classified as a category A agent by the CDC and NIH, requires BSL-4 containment and induces high morbidity and mortality in humans. The 2013-2015 epidemic in West Africa underscored the urgent need to develop vaccines and therapeutics to prevent and treat EBOV disease. Neutralization assays are needed to evaluate the efficacy of EBOV vaccines and antibody therapies. Pseudotyped viruses based on nonpathogenic or attenuated vectors reduce the risks involved in the evaluation of neutralizing antibodies against highly pathogenic viruses. Selectable markers, fluorescent proteins, and luciferase have been introduced into pseudotyped viruses for detection and quantitation purposes. The current study describes the development of a BSL-2 fluorescence reduction neutralization test (FRNT) using a recombinant vesicular stomatitis virus (VSV) in which the VSV-G envelope gene was replaced with the EBOV glycoprotein (GP) and green fluorescent protein (GFP) genes (rVSV-EBOVgp-GFP). Cells infected with rVSV-EBOVgp-GFP express GFP. Anti-GP neutralizing monoclonal and polyclonal antibodies blocked rVSV-EBOVgp-GFP infection preventing or reducing GFP fluorescence. The high degree of correlation between the EBOV BSL-2 FRNT and the BSL-4 plaque reduction neutralization test (PRNT), the accepted standard of EBOV neutralization tests, supports the use of the EBOV BSL-2 FRNT to evaluate neutralizing antibodies in clinical trials. Published by Elsevier B.V.
Lumlertdacha, Boonlert; Wacharapluesadee, Supaporn; Chanhome, Lawan; Hemachudha, Thiravat
2005-07-01
A study of bat lyssavirus survey was done in Thailand from 2001 to 2003. A total of 932 bats of 11 species were captured in 8 provinces for blood collection and testing for neutralizing antibodies against rabies virus (RABV), Australian bat lyssavirus (ABLV) and broader panel of other lyssaviruses (Irkut, Aravan and Khujand). All Thai bat samples were negative to RABV Sixteen samples of 394 with sufficient volume of serum had detectable neutralizing antibodies against Irkut, Aravan, Khujand and ABL viruses. Another 13 samples were also found to have antibody to ABLV. However, due to insufficient volume, further analysis to other lyssaviruses could not be performed. Nevertheless, this showed that the prevalence of lyssavirus infection in Thai bats could be as high as 7.3% (29/396). The present study showed that natural occurrence of lyssavirus antibodies found in Thai bats were related to newer putative lyssavirus genotype(s) other than those previously described. These data also suggest that several lyssaviruses are in circulation throughout Thailand as well as other Asian countries, such as in the Philippines, Central Asia, and in certain parts of Russia. The present study and preparation of this article was supported by grants from the Thailand Research Fund and the National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Thailand.
Serological evidence of arenavirus circulation among fruit bats in Trinidad.
Malmlov, Ashley; Seetahal, Janine; Carrington, Christine; Ramkisson, Vernie; Foster, Jerome; Miazgowicz, Kerri L; Quackenbush, Sandra; Rovnak, Joel; Negrete, Oscar; Munster, Vincent; Schountz, Tony
2017-01-01
Tacaribe virus (TCRV) was isolated in the 1950s from artibeus bats captured on the island of Trinidad. The initial characterization of TCRV suggested that artibeus bats were natural reservoir hosts. However, nearly 60 years later experimental infections of Jamaican fruit bats (Artibeus jamaicensis) resulted in fatal disease or clearance, suggesting artibeus bats may not be a reservoir host. To further evaluate the TCRV reservoir host status of artibeus bats, we captured bats of six species in Trinidad for evidence of infection. Bats of all four fruigivorous species captured had antibodies to TCRV nucleocapsid, whereas none of the insectivore or nectarivore species did. Many flat-faced fruit-eating bats (A. planirostris) and great fruit-eating bats (A. literatus) were seropositive by ELISA and western blot to TCRV nucleocapsid antigen, as were two of four Seba's fruit bats (Carollia perspicillata) and two of three yellow-shouldered fruit bats (Sturnira lilium). Serum neutralization tests failed to detect neutralizing antibodies to TCRV from these bats. TCRV RNA was not detected in lung tissues or lung homogenates inoculated onto Vero cells. These data indicate that TCRV or a similar arenavirus continues to circulate among fruit bats of Trinidad but there was no evidence of persistent infection, suggesting artibeus bats are not reservoir hosts.
[HCV and HBV seropositivity in university students of the State of Nuevo Leòn, Mexico].
Flores-Castañeda, M S; García-Méndez, B L; Tijerina-Menchaca, R
1996-01-01
Viral hepatitis is a contagious disease. Patients infected with hepatitis B virus (HBV) or hepatitis C virus (HCV), may be either chronically symptomatic or asymptomatic, and suffer cirrhosis and high risk of hepatic carcinoma. Asymptomatic carriers of HBV surface antigen (HBs-Ag) or with anti-HCV antibodies are potentially infectious, and therefore a risk to public health. This work seeks to establish the frequency of seropositivity for HBs-Ag and anti-HCV antibodies in a population of 774 newly accepted students of the Medical School of the Autonomous University of Nuevo Leon, whose average age was 18 years. Second generation ELISA test were used to screen for HBs-Ag and anti-HCV antibodies. HBs-Ag was confirmed by a neutralization test and anti-HCV antibodies were confirmed by a RIBA test. Three sera were positive for HBs-Ag by ELISA and only one serum (0.13% of analyzed samples) was confirmed by the neutralization technique. On the other hand 12 sera were positive for anti-HCV antibodies by ELISA, and eight of these were confirmed by RIBA (1.03% of the analyzed samples). Intensive reactivity bands were found in two sera, and weak reactivity bands were found in six sera. ELISA screening for anti-HCV antibodies showed 0.5% of false positives. This study shows that the frequency of anti-HCV antibodies is 7.95% times higher than that found for HBs-Ag. All seropositive patients were asymptomatic and potentially infective. This demonstrates the need to routinely screen for HBs-Ag and anti-HCV antibodies to establish the prevalence of these diseases in our area.
Kalaycioglu, Handan; Uyar, Yavuz; Sevindi, Demet Furkan; Turkyilmaz, Bedia; Çakir, Vedat; Cindemir, Cengiz; Unal, Belgin; Yağçi-Çağlayik, Dilek; Korukluoglu, Gulay; Ertek, Mustafa; Heyman, Paul; Lundkvist, Åke
2013-01-01
Abstract This study was carried out to better understand the epidemiology of hantaviruses in a province of Turkey (Giresun) where human hantavirus disease has recently been detected. In this cross-sectional study, a total of 626 blood samples from healthy people aged 15 and 84 years old were collected both in urban and rural areas in 2009. The sera were tested by enzyme-linked immunosorbent assay (ELISA), immunoblotting assay, and the focus reduction neutralization test (FRNT). We screened the samples by an ELISA and found that 65/626 samples reacted positively for the presence of hantavirus-reactive immunoglobulin G (IgG). Twenty of the 65 ELISA-positive samples could be confirmed by an immunobloting assay, and the overall seroprevalence was thereby calculated to 3.2% (20/626). The seroprevalence of the people living in wood areas or adobe houses 9/17 (52.9%) was significantly higher than among people living in concrete houses 10/47 (21.3%) (p=0.014). Finally, 3 of the 20 immunoblot-positive sera were confirmed as specific for the Puumala hantavirus serotype by FRNT, 1 serum was confirmed as Dobrava virus-specific, whereas 1 serum was found to be equally reactive to Dobrava and Saaremaa viruses. We will now focus on further investigations of the ecology and epidemiology of hantaviruses in humans and their carrier animals in Turkey, studies that have already been started and will be further intensified. PMID:23289396
2013-01-01
Latent equine herpesvirus type 1 (EHV-1) infection is common in horse populations worldwide and estimated to reach a prevalence nearing 90% in some areas. The virus causes acute outbreaks of disease that are characterized by abortion and sporadic cases of myeloencephalopathy (EHM), both severe threats to equine facilities. Different strains vary in their abortigenic and neuropathogenic potential and the simultaneous occurrence of EHM and abortion is rare. In this report, we present clinical observations collected during an EHV-1 outbreak caused by a so-called “neuropathogenic” EHV-1 G2254/D752 polymerase (Pol) variant, which has become more prevalent in recent years and is less frequently associated with abortions. In this outbreak with 61 clinically affected horses, 6/7 pregnant mares aborted and 8 horses developed EHM. Three abortions occurred after development of EHM symptoms. Virus detection was performed by nested PCR targeting gB from nasal swabs (11 positive), blood serum (6 positive) and peripheral blood mononuclear cells (9 positive) of a total of 42 horses sampled. All 6 fetuses tested positive for EHV-1 by PCR and 4 by virus isolation. Paired serum neutralization test (SNT) on day 12 and 28 after the index case showed a significant (≥ 4-fold) increase in twelve horses (n = 42; 28.6%). This outbreak with abortions and EHM cases on a single equine facility provided a unique opportunity for the documentation of clinical disease progression as well as diagnostic procedures. PMID:23497661
Vance, David J; Greene, Christopher J; Rong, Yinghui; Mandell, Lorrie M; Connell, Terry D; Mantis, Nicholas J
2015-12-01
Type II heat-labile enterotoxins (HLTs) constitute a promising set of adjuvants that have been shown to enhance humoral and cellular immune responses when coadministered with an array of different proteins, including several pathogen-associated antigens. However, the adjuvant activities of the four best-studied HLTs, LT-IIa, LT-IIb, LT-IIb(T13I), and LT-IIc, have never been compared side by side. We therefore conducted immunization studies in which LT-IIa, LT-IIb, LT-IIb(T13I), and LT-IIc were coadministered by the intradermal route to mice with two clinically relevant protein subunit vaccine antigens derived from the enzymatic A subunit (RTA) of ricin toxin, RiVax and RVEc. The HLTs were tested with low and high doses of antigen and were assessed for their abilities to stimulate antigen-specific serum IgG titers, ricin toxin-neutralizing activity (TNA), and protective immunity. We found that all four HLTs tested were effective adjuvants when coadministered with RiVax or RVEc. LT-IIa was of particular interest because as little as 0.03 μg when coadministered with RiVax or RVEc proved effective at augmenting ricin toxin-specific serum antibody titers with nominal evidence of local inflammation. Collectively, these results justify the need for further studies into the mechanism(s) underlying LT-IIa adjuvant activity, with the long-term goal of evaluating LT-IIa's activity in humans. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Heaton, Christopher; Vyas, Shikhar G; Singh, Gurmukh
2016-04-01
Overuse of laboratory tests is a persistent issue. We examined the use and overuse of serum immunofixation electrophoresis and serum free light chain assays to develop an algorithm for optimizing utilization. A retrospective review of all tests, for investigation of monoclonal gammopathies, for all patients who had any of these tests done from April 24, 2014, through July 25, 2014, was carried out. The test orders were categorized as warranted or not warranted according to criteria presented in the article. A total of 237 patients were tested, and their historical records included 1,503 episodes of testing for one or more of serum protein electrophoresis, serum immunofixation electrophoresis, and serum free light chain assays. Only 46% of the serum immunofixation and 42% serum free light chain assays were warranted. Proper utilization, at our institution alone, would have obviated $64,182.95/year in health care costs, reduced laboratory cost of reagent alone by $26,436.04/year, and put $21,904.92/year of part B reimbursement at risk. Fewer than half of the serum immunofixation and serum free light chain assays added value. The proposed algorithm for testing should improve utilization. Risk to part B billing may be a disincentive to reducing test utilization. © American Society for Clinical Pathology, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Rondel, Caroline; Marcato-Romain, Claire-Emmanuelle; Girbal-Neuhauser, Elisabeth
2013-05-15
A colorimetric assay based on the conventional anthrone reaction was investigated for specific quantification of uronic acids (UA) in the presence of neutral sugars and/or proteins. Scanning of glucose (Glu) and glucuronic acid (GlA) was performed after the reaction with anthrone and a double absorbance reading was made, at 560 nm and at 620 nm, in order to quantify the UA and neutral sugars separately. The assay was implemented on binary or ternary solutions containing Glu, GlA and bovine serum albumin (BSA) in order to validate its specificity towards sugars and check possible interference with other biochemical components such as proteins. Statistical analysis indicated that this assay provided correct quantification of uronic sugars from 50 to 400 mg/l and of neutral sugars from 20 to 80 mg/l, in the presence of proteins with concentrations reaching 600 mg/l. The proposed protocol can be of great interest for simultaneous determination of uronic and neutral sugars in complex biological samples. In particular, it can be used to correctly quantify the Extracellular Polymeric Substances (EPS) isolated from the biological matrix of many bacterial aggregates, even in the presence of EPS extractant such as EDTA. Copyright © 2013 Elsevier Ltd. All rights reserved.
Interplay of HIV-1 phenotype and neutralizing antibody response in pathogenesis of AIDS.
Scarlatti, G; Leitner, T; Hodara, V; Jansson, M; Karlsson, A; Wahlberg, J; Rossi, P; Uhlén, M; Fenyö, E M; Albert, J
1996-06-01
A majority of human immunodeficiency virus type 1 (HIV-1) infected individuals display a rapid loss of CD4+ lymphocytes with fast progression towards overt acquired immunodeficiency syndrome (AIDS). However, a small proportion of individuals infected by HIV-1 remain immunologically intact for many years. In order to identify factors that might influence the pathogenesis of HIV-1 infection, 21 Italian mothers and 11 Swedish homosexual men were studied for the presence of autologous neutralizing antibodies in serum, biological phenotype of virus isolates and envelope variable region 3 (V3) sequences. The results were compared to the risk of mother-to-child transmission and progression of the disease. The presence of a neutralizing antibody response to the autologous virus as well as a virus with slow replicative capacity were linked both to low risk of mother-to-child transmission and non-progression of the disease. Patients whose peripheral blood mononuclear cells contained a mutation in the tip of the V3 loop (Arg318 to serine, lysine or leucine) significantly more often had neutralizing antibodies to autologous virus isolates containing arginine at this position. Thus, it appears that the interplay and balance between neutralizing antibody response of the host and the biological phenotype of HIV-1 strongly influence pathogenesis.
Vaina, Lucia M.; Rana, Kunjan D.; Cotos, Ionela; Li-Yang, Chen; Huang, Melissa A.; Podea, Delia
2014-01-01
Background Deficits in face emotion perception are among the most pervasive aspects of schizophrenia impairments which strongly affects interpersonal communication and social skills. Material/Methods Schizophrenic patients (PSZ) and healthy control subjects (HCS) performed 2 psychophysical tasks. One, the SAFFIMAP test, was designed to determine the impact of subliminally presented affective or neutral images on the accuracy of face-expression (angry or neutral) perception. In the second test, FEP, subjects saw pictures of face-expression and were asked to rate them as angry, happy, or neutral. The following clinical scales were used to determine the acute symptoms in PSZ: Positive and Negative Syndrome (PANSS), Young Mania Rating (YMRS), Hamilton Depression (HAM-D), and Hamilton Anxiety (HAM-A). Results On the SAFFIMAP test, different from the HCS group, the PSZ group tended to categorize the neutral expression of test faces as angry and their response to the test-face expression was not influenced by the affective content of the primes. In PSZ, the PANSS-positive score was significantly correlated with correct perception of angry faces for aggressive or pleasant primes. YMRS scores were strongly correlated with PSZ’s tendency to recognize angry face expressions when the prime was a pleasant or a neutral image. The HAM-D score was positively correlated with categorizing the test-faces as neutral, regardless of the affective content of the prime or of the test-face expression (angry or neutral). Conclusions Despite its exploratory nature, this study provides the first evidence that conscious perception and categorization of facial emotions (neutral or angry) in PSZ is directly affected by their positive or negative symptoms of the disease as defined by their individual scores on the clinical diagnostic scales. PMID:25537115
Vaina, Lucia Maria; Rana, Kunjan D; Cotos, Ionela; Li-Yang, Chen; Huang, Melissa A; Podea, Delia
2014-12-24
Deficits in face emotion perception are among the most pervasive aspects of schizophrenia impairments which strongly affects interpersonal communication and social skills. Schizophrenic patients (PSZ) and healthy control subjects (HCS) performed 2 psychophysical tasks. One, the SAFFIMAP test, was designed to determine the impact of subliminally presented affective or neutral images on the accuracy of face-expression (angry or neutral) perception. In the second test, FEP, subjects saw pictures of face-expression and were asked to rate them as angry, happy, or neutral. The following clinical scales were used to determine the acute symptoms in PSZ: Positive and Negative Syndrome (PANSS), Young Mania Rating (YMRS), Hamilton Depression (HAM-D), and Hamilton Anxiety (HAM-A). On the SAFFIMAP test, different from the HCS group, the PSZ group tended to categorize the neutral expression of test faces as angry and their response to the test-face expression was not influenced by the affective content of the primes. In PSZ, the PANSS-positive score was significantly correlated with correct perception of angry faces for aggressive or pleasant primes. YMRS scores were strongly correlated with PSZ's tendency to recognize angry face expressions when the prime was a pleasant or a neutral image. The HAM-D score was positively correlated with categorizing the test-faces as neutral, regardless of the affective content of the prime or of the test-face expression (angry or neutral). Despite its exploratory nature, this study provides the first evidence that conscious perception and categorization of facial emotions (neutral or angry) in PSZ is directly affected by their positive or negative symptoms of the disease as defined by their individual scores on the clinical diagnostic scales.
Cardona, P-J; Soto, C Y; Martín, C; Giquel, B; Agustí, G; Andreu, Núria; Guirado, E; Sirakova, T; Kolattukudy, P; Julián, E; Luquin, M
2006-01-01
Searching for virulence marking tests for Mycobacterium tuberculosis, Dubos and Middlebrook reported in 1948 that in an alkaline aqueous solution of neutral-red, the cells of the virulent H37Rv M. tuberculosis strain fixed the dye and became red in color, whereas the cells of the avirulent H37Ra M. tuberculosis strain remained unstained. In the 1950 and 1960s, fresh isolates of M. tuberculosis were tested for this neutral-red cytochemical reaction and it was reported that they were neutral-red positive, whereas other mycobacteria of diverse environmental origins that were non-pathogenic for guinea pigs were neutral-red negative. However, neutral-red has not really been proven to be a virulence marker. To test if virulence is in fact correlated to neutral-red, we studied a clinical isolate of M. tuberculosis that was originally neutral-red positive but, after more than 1 year passing through culture mediums, turned neutral-red negative. We found that, in comparison to the original neutral-red positive strain, this neutral-red negative variant was attenuated in two murine models of experimental tuberculosis. Lipid analysis showed that this neutral-red negative natural mutant lost the capacity to synthesize pthiocerol dimycocerosates, a cell wall methyl-branched lipid that has been related to virulence in M. tuberculosis. We also studied the neutral-red of different gene-targeted M. tuberculosis mutants unable to produce pthiocerol dimycocerosates or other cell wall methyl-branched lipids such as sulfolipids, and polyacyltrehaloses. We found a negative neutral-red reaction in mutants that were deficient in more than one type of methyl-branched lipids. We conclude that neutral-red is indeed a marker of virulence and it indicates important perturbations in the external surface of M. tuberculosis cells.
Nomi, Jason S; Rhodes, Matthew G; Cleary, Anne M
2013-01-01
This study examined how participants' predictions of future memory performance are influenced by emotional facial expressions. Participants made judgements of learning (JOLs) predicting the likelihood that they would correctly identify a face displaying a happy, angry, or neutral emotional expression in a future two-alternative forced-choice recognition test of identity (i.e., recognition that a person's face was seen before). JOLs were higher for studied faces with happy and angry emotional expressions than for neutral faces. However, neutral test faces with studied neutral expressions had significantly higher identity recognition rates than neutral test faces studied with happy or angry expressions. Thus, these data are the first to demonstrate that people believe happy and angry emotional expressions will lead to better identity recognition in the future relative to neutral expressions. This occurred despite the fact that neutral expressions elicited better identity recognition than happy and angry expressions. These findings contribute to the growing literature examining the interaction of cognition and emotion.
NASA Astrophysics Data System (ADS)
Popov, Dmitri; Maliev, Slava
Introduction: High doses of radiation induce apoptotic necrosis of radio-sensitive cells. Mild doses of radiation induce apoptosis or controlled programmed death of radio-sensitive cells with-out development of inflammation and formation of Radiation Toxins. Cell apoptotic necrosis initiates Radiation Toxins (RT)formation. Radiation Toxins play an important role as a trig-ger mechanism for inflammation development and cell lysis. If an immunotherapy approach to treatment of the acute radiation syndromes (ARS) were to be developed, a consideration could be given to neutralization of radiation toxins (Specific Radiation Determinants-SRD) by specific antiradiation antibodies. Therapeutic neutralization effects of the blocking anti-radiation antibodies on the circulated RT had been studied. Radiation Toxins were isolated from the central lymph of irradiated animals with Cerebrovascular(Cv ARS),Cardiovascular (Cr ARS),Gastrointestinal(Gi ARS) and Haemopoietic (Hp ARS) forms of ARS. To accomplish this objective, irradiated animals were injected with a preparation of anti-radiation immunoglobulin G (IgG) obtained from hyperimmune donors. Radiation-induced toxins that we call Specific Radiation Determinants (SRD) possess toxic (neurotoxic, haemotoxic) characteristics as well as specific antigenic properties. Depending on direct physiochemical radiation damage, they can induce development of many of the pathological processes associated with ARS. We have tested several specific hyperimmune IgG preparations against these radiation toxins and ob-served that their toxic properties were neutralized by the specific antiradiation IgGs. Material and Methods: A scheme of experiments was following: 1.Isolation of radiation toxins (RT) from the central lymph of irradiated animals with different form of ARS. 2.Transformation of a toxic form of the RT to a toxoid form of the RT. 3.Immunization of radiation naive animals. Four groups of rabbits were inoculated with a toxoid form of SRD radiation toxins to induce hyperimmune serum: Group A -Toxoid form of CV ARS toxins ( SRD-1); Group B-Toxoid form of CR ARS (SRD-2)toxins ; Group C -Toxoid form of GI ARS (SRD-3); Group D -Toxoid form of HP ARS (SRD-4). After the hyperimmune serum was pooled from several animals, purified, and concentrated, the IgG fraction was separated. Enzyme-linked immunosorbent assays of the hyper-immune serum had revealed high titers of IgG with specific binding to radi-ation toxins. The antiradiation IgG preparation was injected into laboratory animals one hour before and three hours after irradiation, and was evaluated for its ability to protect inoculated animals against the development of acute radiation syndromes. Results: Animals that were inoculated with specific antiradiation antibodies before and after receiving lethal irradiation at LD 100/30 exhibited 60-75% survival rate within 30 days. Also, these animals inoculated with the Antiradiation Antitoxin had exhibited markedly reduced clinical symptoms of the ARS, even those ones that did not survive irradiation. Discussion: The results of our experiments have demonstrated that the rabbit hyperimmune IgG preparations directed against SRD toxins provide a significant protection against high doses of radiation. In comparison, the mortality rate of irradiated control animals was 100% in the same time period. The mortality rates of animals treated by the hyperimmune IgG antidote have varied in the different groups of ani-mals and different forms of the ARS. However, significant radioprotection was observed in each group treated with the IgGs. The specific antiradiation antidote IGg isolated from hyperim-mune serum of immunized horses is under study. The specific antiradiation antidote contains antibodies to neurotoxins -SAAN IgG includes 50% IgG to Cv ARS, 25% IgG to Cr ARS and 25 % IgG to Gi ARS. The other type of the Specific antiradiation antidote containes antibodies to hematotoxins -SAAH IgG -100%. A combined variant is under consideration.
Liang, Fang Ting; Granstrom, David E.; Zhao, Xiao Min; Timoney, John F.
1998-01-01
Sarcocystis neurona is the etiologic agent of equine protozoal myeloencephalitis (EPM). Based on an analysis of 25,000 equine serum and cerebrospinal fluid (CSF) samples, including samples from horses with neurologic signs typical of EPM or with histologically or parasitologically confirmed EPM, four major immunoblot band patterns have been identified. Twenty-three serum and CSF samples representing each of the four immunoblot patterns were selected from 220 samples from horses with neurologic signs resembling EPM and examined for inhibitory effects on the infectivity of S. neurona by an in vitro neutralization assay. A high correlation between immunoblot band pattern and neutralizing activity was detected. Two proteins, Sn14 and Sn16 (14 and 16 kDa, respectively), appeared to be important for in vitro infection. A combination of the results of surface protein labeling, immunoprecipitation, Western blotting, and trypsin digestion suggests that these molecules are surface proteins and may be useful components of a vaccine against S. neurona infection. Although S. neurona is an obligate intracellular parasite, it is potentially a target for specific antibodies which may lyse merozoites via complement or inhibit their attachment and penetration to host cells. PMID:9573058
NASA Astrophysics Data System (ADS)
Sakulkhu, Usawadee; Mahmoudi, Morteza; Maurizi, Lionel; Salaklang, Jatuporn; Hofmann, Heinrich
2014-05-01
Because of their biocompatibility and unique magnetic properties, superparamagnetic iron oxide nanoparticles NPs (SPIONs) are recognized as some of the most prominent agents for theranostic applications. Thus, understanding the interaction of SPIONs with biological systems is important for their safe design and efficient applications. In this study, SPIONs were coated with 2 different polymers: polyvinyl alcohol polymer (PVA) and dextran. The obtained NPs with different surface charges (positive, neutral, and negative) were used as a model study of the effect of surface charges and surface polymer materials on protein adsorption using a magnetic separator. We found that the PVA-coated SPIONs with negative and neutral surface charge adsorbed more serum proteins than the dextran-coated SPIONs, which resulted in higher blood circulation time for PVA-coated NPs than the dextran-coated ones. Highly abundant proteins such as serum albumin, serotransferrin, prothrombin, alpha-fetoprotein, and kininogen-1 were commonly found on both PVA- and dextran-coated SPIONs. By increasing the ionic strength, soft- and hard-corona proteins were observed on 3 types of PVA-SPIONs. However, the tightly bound proteins were observed only on negatively charged PVA-coated SPIONs after the strong protein elution.
Perales, J; Amorim, C Z; Rocha, S L; Domont, G B; Moussatché, H
1992-11-01
The pharmacological modulation of mice paw oedema produced by Bothrops jararaca venom (BJV) has been studied. Intraplantar injection of BJV (1-30 micrograms/paw) produced a dose- and time-related oedema, which was maximal 30 min after injection, reduced gradually thereafter and disappeared over 48 h. BJV heated at 100 degrees C for 5 or 15 min blocked local hemorrhage and caused partial inhibition of its oedematogenic activity. The BJV oedema was not inhibited by the anti-histamine meclizine, the inhibitor of histamine and serotonin, cyproheptadine, PAF-acether antagonist WEB 2170 or by the anti-leukotrienes C4/D4, LY 171883. Dexamethasone, aspirin, indomethacin, and the dual cyclooxygenase and lipoxygenase inhibitor BW 755C inhibited BJV-induced oedema indicating that arachidonic acid metabolism products via the cyclooxygenase pathway participate in its genesis and/or maintenance. The antibothropic fraction (ABF) (25-200 micrograms/paw) isolated from Didelphis marsupialis serum neutralized the oedema induced by the venom with and without heating, the hemorrhage induced by BJV and partially blocked the oedema induced by bradykinin and by cellulose sulphate. The oedema produced by histamine, serotonin, PAF-acether or leukotriene C4 was not inhibited.
HCV-specific immune responses induced by CIGB-230 in combination with IFN-α plus ribavirin
Amador-Cañizares, Yalena; Martínez-Donato, Gillian; Álvarez-Lajonchere, Liz; Vasallo, Claudia; Dausá, Mariacarla; Aguilar-Noriega, Daylen; Valenzuela, Carmen; Raíces, Ivette; Dubuisson, Jean; Wychowski, Czeslaw; Cinza-Estévez, Zurina; Castellanos, Marlén; Núñez, Magdalys; Armas, Anny; González, Yaimé; Revé, Ismariley; Guerra, Ivis; Pérez Aguiar, Ángel; Dueñas-Carrera, Santiago
2014-01-01
AIM: To analyze hepatitis C virus (HCV)-specific immune responses in chronically infected patients under triple therapy with interferon-α (IFN-α) plus ribavirin and CIGB-230. METHODS: CIGB-230 was administered in different schedules with respect to IFN-α plus ribavirin therapy. Paired serum and peripheral blood mononuclear cells (PBMC) samples from baseline and end of treatment were analyzed. The HCV-specific humoral response was tested by enzyme-linked immunosorbent assay, neutralizing antibodies were evaluated by cell culture HCV neutralization assays, PBMC proliferation was assayed by carboxyfluorescein succinimidyl ester staining and IFN-γ secretion was assessed by enzyme-linked immunospot. Data on virological and histological response and their association with immune variables are also provided. RESULTS: From week 12 to week 48, all groups of patients showed a significant reduction in mean leukocyte counts. Statistically significant reductions in antibody titers were frequent, but only individuals immunized with CIGB-230 as early add-on treatment sustained the core-IgG response, and the neutralizing antibody response was enhanced only in patients receiving CIGB-230. Cell-mediated immune responses also tended to decline, but significant reductions in IFN-γ secretion and total absence of core-specific lymphoproliferation were exclusive of the control group. Only CIGB-230-immunized individuals showed de novo induced lymphoproliferative responses against the structural antigens. Importantly, it was demonstrated that the quality of the CIGB-230-induced immune response depended on the number of doses and timing of administration in relation to the antiviral therapy. Specifically, the administration of 6 doses of CIGB-230 as late add-on to therapy increased the neutralizing antibody activity and the de novo core-specific IFN-γ secretion, both of which were associated with the sustained virological response. CONCLUSION: CIGB-230, combined with IFN-α-based therapy, modifies the immune response in chronic patients. The study provides evidence for the design of more effective therapeutic vaccine interventions against HCV. PMID:24415868
Bactericidal Action of Fresh Rabbit Blood Against Brucella abortus
Joos, Richard W.; Hall, Wendell H.
1968-01-01
A photometric method was used to measure the bactericidal kinetics for Brucella abortus of freshly drawn rabbit blood during the time before clotting. This antibrucellar activity varied between rabbits in different immunologic states. Nonimmunized rabbits had moderate bactericidal activity after a lag of about 2 min. The blood of some immunized rabbits gave an immediate and strong kill, but in certain other immunized rabbits, especially when hyperimmunized, the bactericidal activity was inhibited. It appeared that serum bactericidins and complement are sometimes as active in unclotted blood as they are in serum. However, this bactericidal activity can be either increased or neutralized by immunization. The prozone bactericidal inhibition phenomenon (Neisser-Wechsberg) found in immune serum may, in fact, reflect inhibition taking place in vivo. Inhibition of the bactericidal activity in blood can contribute to the persistence of chronic infections and individual variations in resistance. PMID:4971893
2015-01-01
To study the importance of the surface charge for cellular uptake of silica nanoparticles (NPs), we synthesized five different single- or multifunctionalized fluorescent silica NPs (FFSNPs) by introducing various ratios of amino and sulfonate groups into their surface. The zeta potential values of these FFSNPs were customized from highly positive to highly negative, while other physicochemical properties remained almost constant. Irrespective of the original surface charge, serum proteins adsorbed onto the surface, neutralized the zeta potential values, and prevented the aggregation of the tailor-made FFSNPs. Depending on the surface charge and on the absence or presence of serum, two opposite trends were found concerning the cellular uptake of FFSNPs. In the absence of serum, positively charged NPs were more strongly accumulated by human osteoblast (HOB) cells than negatively charged NPs. In contrast, in serum-containing medium, anionic FFSNPs were internalized by HOB cells more strongly, despite the similar size and surface charge of all types of protein-covered FFSNPs. Thus, at physiological condition, when the presence of proteins is inevitable, sulfonate-functionalized silica NPs are the favorite choice to achieve a desired high rate of NP internalization. PMID:26030456
Clement, Kristin H; Rudge, Thomas L; Mayfield, Heather J; Carlton, Lena A; Hester, Arelis; Niemuth, Nancy A; Sabourin, Carol L; Brys, April M; Quinn, Conrad P
2010-11-01
Anthrax toxin (ATx) is composed of the binary exotoxins lethal toxin (LTx) and edema toxin (ETx). They have separate effector proteins (edema factor and lethal factor) but have the same binding protein, protective antigen (PA). PA is the primary immunogen in the current licensed vaccine anthrax vaccine adsorbed (AVA [BioThrax]). AVA confers protective immunity by stimulating production of ATx-neutralizing antibodies, which could block the intoxication process at several steps (binding of PA to the target cell surface, furin cleavage, toxin complex formation, and binding/translocation of ATx into the cell). To evaluate ATx neutralization by anti-AVA antibodies, we developed two low-temperature LTx neutralization activity (TNA) assays that distinguish antibody blocking before and after binding of PA to target cells (noncomplexed [NC] and receptor-bound [RB] TNA assays). These assays were used to investigate anti-PA antibody responses in AVA-vaccinated rhesus macaques (Macaca mulatta) that survived an aerosol challenge with Bacillus anthracis Ames spores. Results showed that macaque anti-AVA sera neutralized LTx in vitro, even when PA was prebound to cells. Neutralization titers in surviving versus nonsurviving animals and between prechallenge and postchallenge activities were highly correlated. These data demonstrate that AVA stimulates a myriad of antibodies that recognize multiple neutralizing epitopes and confirm that change, loss, or occlusion of epitopes after PA is processed from PA83 to PA63 at the cell surface does not significantly affect in vitro neutralizing efficacy. Furthermore, these data support the idea that the full-length PA83 monomer is an appropriate immunogen for inclusion in next-generation anthrax vaccines.
Chen, Zhihui; Tang, Ziwei; Xu, Qingqiang; Wang, Yue; Zhao, Ping; Qi, Zhongtian
2013-01-01
Pre-existing immunity is an important factor countering the pandemic potential of an emerging influenza virus strain. Thus, studying of pre-existing immunity to the 2009 pandemic H1N1 virus (2009 H1N1) will advance our understanding of the pathogenesis and epidemiology of this emerging pathogen. In the present study, sera were collected from 486 individuals in a hospital in Shanghai, China, before the 2009 H1N1 influenza pandemic. The serum anti-hemagglutinins (HA) antibody, hemagglutination inhibition (HI) antibody and neutralizing antibody against the 2009 H1N1 were assayed. Among this population, 84.2%, 14.61% and 26.5% subjects possessed anti-HA antibody, HI antibody and neutralizing antibody, respectively. Although neutralizing antibody only existed in those sera with detectable anti-HA antibody, there was no obvious correlation between the titers of anti-HA and neutralizing antibody. However, the titers of anti-HA and neutralizing antibody against seasonal H1N1 virus were highly correlated. In the same population, there was no correlation between titers of neutralizing antibody against 2009 H1N1 and seasonal H1N1. DNA immunization performed on mice demonstrated that antibodies to the HA of 2009 pandemic and seasonal H1N1 influenza viruses were strain-specific and had no cross-neutralizing activity. In addition, the predicted conserved epitope in the HA of 2009 H1N1 and recently circulating seasonal H1N1 virus, GLFGAIAGFIE, was not an immunologically valid B-cell epitope. The data in this report are valuable for advancing our understanding of 2009 H1N1 influenza virus infection. PMID:23527030
McCaw, D L; Thompson, M; Tate, D; Bonderer, A; Chen, Y J
1998-07-01
To determine serum canine distemper virus (CDV) and canine parvovirus (CPV) antibody titers in healthy dogs brought to a veterinary hospital for revaccination. Case series. 122 dogs. Serum antibody titers were measured by means of hemagglutination inhibition (CPV titers) or serum neutralization (CDV titers) at the time dogs were brought to the hospital for revaccination. All dogs had been vaccinated between 271 and 1,665 days previously. Dogs were grouped by age, breed (purebred vs mixed breed), sex, and weight to determine whether these factors were associated with antibody titers. Serum CPV titers > or = 1:80 and serum CDV titers > or = 1:96 were considered protective. Breed, sex, and weight were not significantly associated with serum CPV and CDV titers. Age was significantly associated with CPV titer, with younger dogs having higher titers, but was not associated with CDV titer. Thirty-three of 122 (27%; 95% confidence interval, 19.0 to 34.9%) dogs had a less-than-protective CPV titer. Twenty-five of 117 (21%; 95% confidence interval, 13.6 to 28.4%) dogs had a less-than-protective CDV titer. Results suggest that, on the basis of serum antibody titers, the current practice of annual revaccination of dogs against CPV and CDV infection should be maintained. Measurement of antibody titers to determine whether revaccination is truly needed would seem justifiable in those dogs that have previously had an adverse reaction to vaccination.
DeBuysscher, Blair L.; Scott, Dana; Marzi, Andrea; Prescott, Joseph; Feldmann, Heinz
2016-01-01
Background Nipah virus (NiV), a zoonotic pathogen causing severe respiratory illness and encephalitis in humans, emerged in Malaysia in 1998 with subsequent outbreaks on an almost annual basis since 2001 in parts of the Indian subcontinent. The high case fatality rate, human-to-human transmission, wide-ranging reservoir distribution and lack of licensed intervention options are making NiV a serious regional and potential global public health problem. The objective of this study was to develop a fast-acting, single-dose NiV vaccine that could be implemented in a ring vaccination approach during outbreaks. Methods In this study we have designed new live-attenuated vaccine vectors based on recombinant vesicular stomatitis viruses (rVSV) expressing NiV glycoproteins (G or F) or nucleoprotein (N) and evaluated their protective efficacy in Syrian hamsters, an established NiV animal disease model. We further characterized the humoral immune response to vaccination in hamsters using ELISA and neutralization assays and performed serum transfer studies. Results Vaccination of Syrian hamsters with a single dose of the rVSV vaccine vectors resulted in strong humoral immune responses with neutralizing activities found only in those animals vaccinated with rVSV expressing NiV G or F proteins. Vaccinated animals with neutralizing antibody responses were completely protected from lethal NiV disease, whereas animals vaccinated with rVSV expressing NiV N showed only partial protection. Protection of NiV G or F vaccinated animals was conferred by antibodies, most likely the neutralizing fraction, as demonstrated by serum transfer studies. Protection of N-vaccinated hamsters was not antibody-dependent indicating a role of adaptive cellular responses for protection. Conclusions The rVSV vectors expressing Nipah virus G or F are prime candidates for new ‘emergency vaccines’ to be utilized for NiV outbreak management. PMID:24631094
DeBuysscher, Blair L; Scott, Dana; Marzi, Andrea; Prescott, Joseph; Feldmann, Heinz
2014-05-07
Nipah virus (NiV), a zoonotic pathogen causing severe respiratory illness and encephalitis in humans, emerged in Malaysia in 1998 with subsequent outbreaks on an almost annual basis since 2001 in parts of the Indian subcontinent. The high case fatality rate, human-to-human transmission, wide-ranging reservoir distribution and lack of licensed intervention options are making NiV a serious regional and potential global public health problem. The objective of this study was to develop a fast-acting, single-dose NiV vaccine that could be implemented in a ring vaccination approach during outbreaks. In this study we have designed new live-attenuated vaccine vectors based on recombinant vesicular stomatitis viruses (rVSV) expressing NiV glycoproteins (G or F) or nucleoprotein (N) and evaluated their protective efficacy in Syrian hamsters, an established NiV animal disease model. We further characterized the humoral immune response to vaccination in hamsters using ELISA and neutralization assays and performed serum transfer studies. Vaccination of Syrian hamsters with a single dose of the rVSV vaccine vectors resulted in strong humoral immune responses with neutralizing activities found only in those animals vaccinated with rVSV expressing NiV G or F proteins. Vaccinated animals with neutralizing antibody responses were completely protected from lethal NiV disease, whereas animals vaccinated with rVSV expressing NiV N showed only partial protection. Protection of NiV G or F vaccinated animals was conferred by antibodies, most likely the neutralizing fraction, as demonstrated by serum transfer studies. Protection of N-vaccinated hamsters was not antibody-dependent indicating a role of adaptive cellular responses for protection. The rVSV vectors expressing Nipah virus G or F are prime candidates for new 'emergency vaccines' to be utilized for NiV outbreak management. Published by Elsevier Ltd.
Nie, Xin-Zheng; Chen, Sha; Zhang, Xiao-Xu; Dai, Bin-Yang; Qian, Li-Chun
A feeding trial was conducted for nine weeks to investigate the effects of partially replacing Ca(H 2 PO 4 ) 2 with neutral phytase on the growth performance, phosphorus utilization, nutrient digestibility, serum biochemical parameters, bone and carcass mineral composition, and digestive-enzyme-specific activity in crucian carp (Carassius auratus). The diets prepared with 0.8%, 0%, and 1.8% Ca(H 2 PO 4 ) 2 (1%=1 g/100 g) supplements were regarded as the P 1 E 0 , negative control (NC), and positive control (PC) groups, respectively; the other three experimental diets were prepared with the addition of 200, 300, and 500 U/kg of neutral phytase, respectively, based on the P 1 E 0 group. Three hundred and eighty-four fish ((1.50±0.01) g) were randomly distributed in the six treatments with four replicates each. The fish were initially fed with 2%-3% diets of their body weight per day, with feeding twice daily (08:00 and 16:00), under a 12-h light/12-h dark cycle at the temperature of (27.56±0.89) °C. The results showed that supplemental phytase at different levels in the diet improved the final body weight, average daily gain, feed conversion ratio, phosphorus utilization, and protein efficiency ratio of crucian carp (P<0.05). Phytase supplementation increased the mineral content in serum (P), bone (P, Ca), and carcass (P, Ca, Zn, Na, and Mg) (P<0.05); the trypsin and chymotrypsin activity soared when fed with the phytase-supplemented diets (P<0.05). We may conclude that supplemental dietary neutral phytase improved the growth performance, phosphorus utilization as well as nutrient utilization in crucian carp, and it can be considered an important nutritional replacement for Ca(H 2 PO 4 ) 2 .
Zhou, Min; Kitagawa, Yoshinori; Yamaguchi, Mayu; Uchiyama, Chika; Itoh, Masae; Gotoh, Bin
2013-01-01
Human metapneumovirus (HMPV) is a common cause of respiratory diseases in persons of all ages. Because of its slow replication and weak cytopathic effect in cultured cells, conventional neutralization assays for HMPV require around one week for completion. The purpose of this study is to establish a rapid neutralization assay based on a recombinant virus expressing Renilla luciferase (Rluc). A recombinant HMPV expressing both Rluc and green fluorescent protein (GFP) was created by reverse genetics method. Two-fold serial dilutions of human 23 sera were made in a 96-well plate and incubated with 50 pfu/well of the recombinant virus at 4°C for 1 h. The mixtures were then transferred to LLC-MK2 cells in a 96-well plate, incubated for 2 h, and replaced with trypsin-free fresh media. After incubation at 32°C for 24 h, the cells were lysed and measured for Rluc activity. The neutralization titer was defined as the reciprocal of the highest serum dilution that resulted in 50% reduction of Rluc activity. The novel assay could be completed within 24 h and eliminated the requirement of trypsin supporting multistep replication in cultured cells, as well as laborious processes including the plaque assay with immunostaining. Neutralization titers correlated well with those determined by a GFP-based assay previously developed. The neutralization assay based on Rluc activity is the fastest and the most straightforward of all previous assays, and may be available for high throughput screening of neutralizing antibodies. Copyright © 2012 Elsevier B.V. All rights reserved.
21 CFR 866.5700 - Whole human plasma or serum immunological test system.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Whole human plasma or serum immunological test... Systems § 866.5700 Whole human plasma or serum immunological test system. (a) Identification. A whole human plasma or serum immunological test system is a device that consists of reagents used to measure by...
21 CFR 866.5700 - Whole human plasma or serum immunological test system.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Whole human plasma or serum immunological test... Systems § 866.5700 Whole human plasma or serum immunological test system. (a) Identification. A whole human plasma or serum immunological test system is a device that consists of reagents used to measure by...
21 CFR 866.5700 - Whole human plasma or serum immunological test system.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Whole human plasma or serum immunological test... Systems § 866.5700 Whole human plasma or serum immunological test system. (a) Identification. A whole human plasma or serum immunological test system is a device that consists of reagents used to measure by...
21 CFR 866.5700 - Whole human plasma or serum immunological test system.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Whole human plasma or serum immunological test... Systems § 866.5700 Whole human plasma or serum immunological test system. (a) Identification. A whole human plasma or serum immunological test system is a device that consists of reagents used to measure by...
21 CFR 866.5700 - Whole human plasma or serum immunological test system.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Whole human plasma or serum immunological test... Systems § 866.5700 Whole human plasma or serum immunological test system. (a) Identification. A whole human plasma or serum immunological test system is a device that consists of reagents used to measure by...
Nest survival estimation: a review of alternatives to the Mayfield estimator
Jehle, G.; Yackel Adams, A.A.; Savidge, J.A.; Skagen, S.K.
2004-01-01
Our research has focused on the ecology of commensal populations of big brown bats (Eptesicus fuscus) in Fort Collins, Colorado (USA), in relation to rabies virus (RV) transmission. We captured 35 big brown bats (Eptesicus fuscus) in late summer 2001 and held them captive for 4.8 mo. The bats were initially placed in an indoor cage for 1 mo then segregated into groups of two to six per cage. Two of the bats succumbed to rabies virus (RV) within the first month of capture. Despite group housing, all of the remaining bats were healthy over the course of the investigation; none developed rabies, although one of the rabid bats was observed to bite her cage mates. Reverse transcription–polymerase chain reaction (RT-PCR) and Taqman® real-time PCR analysis of the RNA derived from the brain tissue, salivary glands, and oral swab samples confirmed RV infection in the dead bats. Rabies virus was also isolated from the brain tissue upon passage in mouse neuroblastoma cells. Nucleotide sequence analysis of the RV nucleoprotein (N) gene showed 100% identity with the N gene sequence of a 1985 E. fuscus isolate from El Paso County, Colorado. Bat sera obtained six times throughout the study were assayed for RV neutralizing antibodies using the rapid fluorescent focus inhibition test. The RV neutralizing activity in the serum was associated with the IgG component, which was purified by binding to protein G Sepharose. Five bats were RV seropositive prior to their capture and maintained titers throughout captivity. Two adult bats seroconverted during captivity. Two volant juvenile bats had detectable RV antibody titers at the first serum collection but were negative thereafter. Four seronegative bats responded to a RV vaccine administration with high titers of RV antibodies. A serologic survey of big brown bats in the roost from which one of the captive rabid bats had originated showed a significant rise in seroprevalence during 2002.
Rabies in a captive colony of big brown bats (Eptesicus fuscus)
Shankar, V.; Bowen, R.A.; Davis, A.D.; Rupprecht, C.E.; O'Shea, T.J.
2004-01-01
Our research has focused on the ecology of commensal populations of big brown bats (Eptesicus fuscus) in Fort Collins, Colorado (USA), in relation to rabies virus (RV) transmission. We captured 35 big brown bats (Eptesicus fuscus) in late summer 2001 and held them captive for 4.8 mo. The bats were initially placed in an indoor cage for 1 mo then segregated into groups of two to six per cage. Two of the bats succumbed to rabies virus (RV) within the first month of capture. Despite group housing, all of the remaining bats were healthy over the course of the investigation; none developed rabies, although one of the rabid bats was observed to bite her cage mates. Reverse transcription–polymerase chain reaction (RT-PCR) and Taqman® real-time PCR analysis of the RNA derived from the brain tissue, salivary glands, and oral swab samples confirmed RV infection in the dead bats. Rabies virus was also isolated from the brain tissue upon passage in mouse neuroblastoma cells. Nucleotide sequence analysis of the RV nucleoprotein (N) gene showed 100% identity with the N gene sequence of a 1985 E. fuscus isolate from El Paso County, Colorado. Bat sera obtained six times throughout the study were assayed for RV neutralizing antibodies using the rapid fluorescent focus inhibition test. The RV neutralizing activity in the serum was associated with the IgG component, which was purified by binding to protein G Sepharose. Five bats were RV seropositive prior to their capture and maintained titers throughout captivity. Two adult bats seroconverted during captivity. Two volant juvenile bats had detectable RV antibody titers at the first serum collection but were negative thereafter. Four seronegative bats responded to a RV vaccine administration with high titers of RV antibodies. A serologic survey of big brown bats in the roost from which one of the captive rabid bats had originated showed a significant rise in seroprevalence during 2002.
Intranasal and sublingual delivery of inactivated polio vaccine.
Kraan, Heleen; Soema, Peter; Amorij, Jean-Pierre; Kersten, Gideon
2017-05-09
Polio is on the brink of eradication. Improved inactivated polio vaccines (IPV) are needed towards complete eradication and for the use in the period thereafter. Vaccination via mucosal surfaces has important potential advantages over intramuscular injection using conventional needle and syringe, the currently used delivery method for IPV. One of them is the ability to induce both serum and mucosal immune responses: the latter may provide protection at the port of virus entry. The current study evaluated the possibilities of polio vaccination via mucosal surfaces using IPV based on attenuated Sabin strains. Mice received three immunizations with trivalent sIPV via intramuscular injection, or via the intranasal or sublingual route. The need of an adjuvant for the mucosal routes was investigated as well, by testing sIPV in combination with the mucosal adjuvant cholera toxin. Both intranasal and sublingual sIPV immunization induced systemic polio-specific serum IgG in mice that were functional as measured by poliovirus neutralization. Intranasal administration of sIPV plus adjuvant induced significant higher systemic poliovirus type 3 neutralizing antibody titers than sIPV delivered via the intramuscular route. Moreover, mucosal sIPV delivery elicited polio-specific IgA titers at different mucosal sites (IgA in saliva, fecal extracts and intestinal tissue) and IgA-producing B-cells in the spleen, where conventional intramuscular vaccination was unable to do so. However, it is likely that a mucosal adjuvant is required for sublingual vaccination. Further research on polio vaccination via sublingual mucosal route should include the search for safe and effective adjuvants, and the development of novel oral dosage forms that improve antigen uptake by oral mucosa, thereby increasing vaccine immunogenicity. This study indicates that both the intranasal and sublingual routes might be valuable approaches for use in routine vaccination or outbreak control in the period after complete OPV cessation and post-polio eradication. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Falconi, Caterina; López-Olvera, Jorge Ramón; Boadella, Mariana; Camarena, Javier; Rosell, Rosa; Alcaide, Vicente; Vicente, Joaquín; Sánchez-Vizcaíno, José Manuel; Pujols, Joan; Gortázar, Christian
2012-09-14
Bluetongue (BT) is an infectious disease of wild and domestic ruminants caused by bluetongue virus (BTV). BTV-4 spread through southern Spain from 2004 to 2006, whereas a BTV-1 outbreak that started in southern Spain in 2007 is still ongoing. Vaccination and movement restriction regulations are applied to domestic ruminants to control BT, but the potential reservoir role of wild European ungulates has not been clarified so far. The aim of this study was to describe the epidemiology of BTV in the wild free-ranging red deer (Cervus elaphus) population of Cabañeros National Park (CNP) in central Spain during the BTV-4 and BTV-1 epizootics, assessing the potential role of this deer population as a BTV reservoir. Blood samples from 2885 (2542 adults, 208 calves and 135 undetermined) wild red deer were collected from 2005 to 2010 in CNP and surrounding hunting estates. All sera were tested for antibodies against the BTV VP7 protein by ELISA. Ninety-four of the ELISA-positive samples were analysed by serum neutralization to detect BTV-4 and BTV-1 specific antibodies, and 142 blood samples were analysed by RT-PCR for BTV RNA. A total of 371 (12.9%) out of the 2,885 deer (35/208 calves, 307/2,542 adults, and 29/135 undetermined) were positive for antibodies against BTV. Prevalence increased in adult deer from 2005-2006 to 2008-2009, declining thereafter. No positive samples for BTV-1 were found by serum neutralization, whereas 43 deer (38 adults, four calves and one undetermined) were positive for BTV-4 specific antibodies. No BTV RNA positive deer were found by RT-PCR. Antibody detection throughout the study period suggests a maintained circulation of BTV in red deer. However, the lack of BTV RNA detection suggests a minor transmission risk to livestock. Copyright © 2012 Elsevier B.V. All rights reserved.
Serum antibody titers following routine rabies vaccination in African elephants.
Miller, Michele A; Olea-Popelka, Francisco
2009-10-15
To evaluate serum antibody titers in captive African elephants (Loxodonta africana) following routine vaccination with a commercially available, inactivated rabies vaccine. Seroepidemiologic study. 14 captive African elephants from a single herd. Elephants were vaccinated as part of a routine preventive health program. Initially, elephants were vaccinated annually (2 mL, IM), and blood was collected every 4 or 6 months for measurement of rabies virus-neutralizing antibody titer by means of the rapid fluorescent focus inhibition test. Individual elephants were later switched to an intermittent vaccination schedule to allow duration of the antibody response to be determined. All elephants had detectable antibody responses following rabies vaccination, although there was great variability among individual animals in regard to antibody titers, and antibody titers could be detected as long as 24 months after vaccine administration. Young animals were found to develop an antibody titer following administration of a single dose of the rabies vaccine. Age and time since vaccination had significant effects on measured antibody titers. Results indicated that African elephants developed detectable antibody titers in response to inoculation with a standard large animal dose of a commercially available, inactivated rabies vaccine. The persistence of detectable antibody titers in some animals suggested that vaccination could be performed less frequently than once a year if antibody titers were routinely monitored.
Adjuvant-enhanced CD4 T Cell Responses are Critical to Durable Vaccine Immunity.
Martins, Karen A O; Cooper, Christopher L; Stronsky, Sabrina M; Norris, Sarah L W; Kwilas, Steven A; Steffens, Jesse T; Benko, Jacqueline G; van Tongeren, Sean A; Bavari, Sina
2016-01-01
Protein-based vaccines offer a safer alternative to live-attenuated or inactivated vaccines but have limited immunogenicity. The identification of adjuvants that augment immunogenicity, specifically in a manner that is durable and antigen-specific, is therefore critical for advanced development. In this study, we use the filovirus virus-like particle (VLP) as a model protein-based vaccine in order to evaluate the impact of four candidate vaccine adjuvants on enhancing long term protection from Ebola virus challenge. Adjuvants tested include poly-ICLC (Hiltonol), MPLA, CpG 2395, and alhydrogel. We compared and contrasted antibody responses, neutralizing antibody responses, effector T cell responses, and T follicular helper (Tfh) cell frequencies with each adjuvant's impact on durable protection. We demonstrate that in this system, the most effective adjuvant elicits a Th1-skewed antibody response and strong CD4 T cell responses, including an increase in Tfh frequency. Using immune-deficient animals and adoptive transfer of serum and cells from vaccinated animals into naïve animals, we further demonstrate that serum and CD4 T cells play a critical role in conferring protection within effective vaccination regimens. These studies inform on the requirements of long term immune protection, which can potentially be used to guide screening of clinical-grade adjuvants for vaccine clinical development.
SHIRAISHI, Rikiya; NISHIMURA, Masaaki; NAKASHIMA, Ryuji; ENTA, Chiho; HIRAYAMA, Norio
2013-01-01
ABSTRACT In Japan, the import quarantine regulation against rabies has required from 2005 that dogs and cats should be inoculated with the rabies vaccine and that the neutralizing antibody titer should be confirmed to be at least 0.5 international units (IU)/ml. The fluorescent antibody virus neutralization (FAVN) test is used as an international standard method for serological testing for rabies. To achieve proper immunization of dogs and cats at the time of import and export, changes in the neutralizing antibody titer after inoculation of the rabies vaccine should be understood in detail. However, few reports have provided this information. In this study, we aimed to determine evaluated, such changes by using sera from experimental dogs and cats inoculated with the rabies vaccine, and we tested samples using the routine FAVN test. In both dogs and cats, proper, regular vaccination enabled the necessary titer of neutralizing antibodies to be maintained in the long term. However, inappropriate timing of blood sampling after vaccination could result in insufficient detected levels of neutralizing antibodies. PMID:24389741
Shiraishi, Rikiya; Nishimura, Masaaki; Nakashima, Ryuji; Enta, Chiho; Hirayama, Norio
2014-04-01
In Japan, the import quarantine regulation against rabies has required from 2005 that dogs and cats should be inoculated with the rabies vaccine and that the neutralizing antibody titer should be confirmed to be at least 0.5 international units (IU)/ml. The fluorescent antibody virus neutralization (FAVN) test is used as an international standard method for serological testing for rabies. To achieve proper immunization of dogs and cats at the time of import and export, changes in the neutralizing antibody titer after inoculation of the rabies vaccine should be understood in detail. However, few reports have provided this information. In this study, we aimed to determine evaluated, such changes by using sera from experimental dogs and cats inoculated with the rabies vaccine, and we tested samples using the routine FAVN test. In both dogs and cats, proper, regular vaccination enabled the necessary titer of neutralizing antibodies to be maintained in the long term. However, inappropriate timing of blood sampling after vaccination could result in insufficient detected levels of neutralizing antibodies.
Torres, J F; Lyerly, D M; Hill, J E; Monath, T P
1995-01-01
Clostridium difficile produces toxins that cause inflammation, necrosis, and fluid in the intestine and is the most important cause of nosocomial antibiotic-associated diarrhea and colitis. We evaluated C. difficile antigens as vaccines to protect against systemic and intestinal disease in a hamster model of clindamycin colitis. Formalin-inactivated culture filtrates from a highly toxigenic strain were administered by mucosal routes (intranasal, intragastric, and rectal) with cholera toxin as a mucosal adjuvant. A preparation of culture filtrate and killed whole cells was also tested rectally. The toxoid was also tested parenterally (subcutaneously and intraperitoneally) and by a combination of three intranasal immunizations followed by a combined intranasal-intraperitoneal boost. Serum antibodies against toxins A and B and whole-cell antigen were measured by enzyme-linked immunosorbent assay, neutralization of cytotoxic activity, and bacterial agglutination. The two rectal immunization regimens induced low antibody responses and protected only 20% of hamsters against death and 0% against diarrhea. The intragastric regimen induced high antibody responses but low protection, 40% against death and 0% against diarrhea. Hamsters immunized by the intranasal, intraperitoneal, and subcutaneous routes were 100% protected against death and partially protected (40, 40, and 20%, respectively) against diarrhea. Among the latter groups, intraperitoneally immunized animals had the highest serum anticytotoxic activity and the highest agglutinating antibody responses. Hamsters immunized intranasally and revaccinated intraperitoneally were 100% protected against both death and diarrhea. Protection against death and diarrhea correlated with antibody responses to all antigens tested. The results indicate that optimal protection against C. difficile disease can be achieved with combined parenteral and mucosal immunization. PMID:7591115
Characteristics of respiratory tract disease in horses inoculated with equine rhinitis A virus.
Diaz-Méndez, Andrés; Hewson, Joanne; Shewen, Patricia; Nagy, Eva; Viel, Laurent
2014-02-01
To develop a method for experimental induction of equine rhinitis A virus (ERAV) infection in equids and to determine the clinical characteristics of such infection. 8 ponies (age, 8 to 12 months) seronegative for antibodies against ERAV. PROCEDURES-Nebulization was used to administer ERAV (strain ERAV/ON/05; n = 4 ponies) or cell culture medium (control ponies; 4) into airways of ponies; 4 previously ERAV-inoculated ponies were reinoculated 1 year later. Physical examinations and pulmonary function testing were performed at various times for 21 days after ERAV or mock inoculation. Various types of samples were obtained for virus isolation, blood samples were obtained for serologic testing, and clinical scores were determined for various variables. ERAV-inoculated ponies developed respiratory tract disease characterized by pyrexia, nasal discharge, adventitious lung sounds, and enlarged mandibular lymph nodes. Additionally, these animals had purulent mucus in lower airways up to the last evaluation time 21 days after inoculation (detected endoscopically). The virus was isolated from various samples obtained from lower and upper airways of ERAV-inoculated ponies up to 7 days after exposure; this time corresponded with an increase in serum titers of neutralizing antibodies against ERAV. None of the ponies developed clinical signs of disease after reinoculation 1 year later. Results of this study indicated ERAV induced respiratory tract disease in seronegative ponies. However, ponies with neutralizing antibodies against ERAV did not develop clinical signs of disease when reinoculated with the virus. Therefore, immunization of ponies against ERAV could prevent respiratory tract disease attributable to that virus in such animals.
Brent, Carolyn; Dunn, Angela; Savage, Harry; Faraji, Ary; Rubin, Mike; Risk, Ilene; Garcia, Wendy; Cortese, Margaret; Novosad, Shannon; Krow-Lucal, Elisabeth Raquel; Crain, Jacqueline; Hill, Mary; Atkinson, Annette; Peterson, Dallin; Christensen, Kimberly; Dimond, Melissa; Staples, J Erin; Nakashima, Allyn
2016-09-16
On July 12, 2016, the Utah Department of Health (UDOH) was notified by a clinician caring for an adult (patient A) who was evaluated for fever, rash, and conjunctivitis that began on July 1. Patient A had not traveled to an area with ongoing Zika virus transmission; had not had sexual contact with a person who recently traveled; and had not received a blood transfusion, organ transplant, or mosquito bites (1). Patient A provided care over several days to an elderly male family contact (the index patient) who contracted Zika virus abroad. The index patient developed septic shock with multiple organ failure and died in the hospital on June 25, 2016. The index patient's blood specimen obtained 2 days before his death had a level of viremia approximately 100,000 times higher than the average level reported in persons infected with Zika virus (2). Zika virus infection was diagnosed in patient A by real-time reverse transcription-polymerase chain reaction (rRT-PCR) testing on a urine specimen collected 7 days after symptom onset. In addition, a serum specimen collected 11 days after symptom onset, after patient A's symptoms had resolved, was positive for antibodies to Zika virus by Zika immunoglobulin M (IgM) capture enzyme-linked immunosorbent assay (MAC-ELISA) and had neutralizing antibodies detected by plaque-reduction neutralization testing (PRNT). Working with Salt Lake and Davis County Health Departments, UDOH requested assistance from CDC with an investigation to determine patient A's exposures and determine a probable source of infection.
Outer membrane vesicles shield Moraxella catarrhalis β-lactamase from neutralization by serum IgG.
Schaar, Viveka; Paulsson, Magnus; Mörgelin, Matthias; Riesbeck, Kristian
2013-03-01
The aim of this study was to detect the presence of IgG against Moraxella catarrhalis β-lactamase in healthy adults, and to determine whether outer membrane vesicles (OMVs) could protect the enzyme from inhibition by anti-β-lactamase IgG. Transmission electron microscopy was used to detect the presence of β-lactamase in OMVs. Sera were examined by ELISA for specific IgG directed against recombinant M. catarrhalis β-lactamase in addition to the outer membrane adhesins MID/Hag, UspA1 and A2. Binding of anti-β-lactamase IgG from serum to OMVs was analysed by flow cytometry. The chromogenic substrate nitrocefin was used to quantify β-lactamase enzyme activity. The presence of β-lactamase was determined in OMVs from a 9-year-old child suffering from M. catarrhalis sinusitis. Furthermore, anti-β-lactamase IgG was detected in sera obtained from healthy adults. Out of 40 adult blood donors (aged 18-65 years) tested, 6 (15.0%) carried anti-β-lactamase IgG. No correlation between IgG titres against β-lactamase and the adhesins was found. Flow cytometry analyses revealed that anti-β-lactamase IgG from serum bound to β-lactamase-positive OMVs. By comparing the β-lactamase activity of intact OMV with OMV that were permeabilized with saponin we found that OMVs shielded active β-lactamase from the anti-β-lactamase IgG. Moraxella catarrhalis β-lactamase is found in, or associated with, OMVs, providing clinical relevance for the vesicles in the spread of antibiotic resistance. Furthermore, OMVs protect β-lactamase from specific IgG.
Immunodiagnostic Techniques for Bacterial Infections
1981-01-01
specificity that specific immune sera (the immune response) provides. The early use of immunological diagnosis was to demonstrate circulating antibodies to...testing requirements. 4. Carefully remove punched plugs by suction. 5. Fill the central well with immune serum and the surrounding wells with test...capsulatuni Serum Actinomvcesr israeli Serum Aspergillus fumiqatus Serum Protozoan: Trvnanosoma cruzi Serum Entameaba histolvtica Serum Trichinella sviralis
Barban, Veronique; Munoz-Jordan, Jorge L; Santiago, Gilberto A; Mantel, Nathalie; Girerd, Yves; Gulia, Sandrine; Claude, Jean-Baptiste; Lang, Jean
2012-08-01
The objective of the study was to evaluate if the antibodies elicited after immunization with a tetravalent dengue vaccine, based on chimeric yellow fever 17D/dengue viruses, can neutralize a large range of dengue viruses (DENV). A panel of 82 DENVs was developed from viruses collected primarily during the last decade in 30 countries and included the four serotypes and the majority of existing genotypes. Viruses were isolated and minimally amplified before evaluation against a tetravalent polyclonal serum generated during vaccine preclinical evaluation in monkey, a model in which protection efficacy of this vaccine has been previously demonstrated (Guirakhoo et al., 2004). Neutralization was observed across all the DENV serotypes, genotypes, geographical origins and isolation years. These data indicate that antibodies elicited after immunization with this dengue vaccine candidate should widely protect against infection with contemporary DENV lineages circulating in endemic countries. Copyright © 2012 Elsevier Inc. All rights reserved.
Memish, Ziad A; Alsahly, Ahmad; Masri, Malak al; Heil, Gary L; Anderson, Benjamin D; Peiris, Malik; Khan, Salah Uddin; Gray, Gregory C
2015-01-01
Middle East respiratory syndrome coronavirus (MERS-CoV) is an emerging viral pathogen that primarily causes respiratory illness. We conducted a seroprevalence study of banked human serum samples collected in 2012 from Southern Saudi Arabia. Sera from 300 animal workers (17% with daily camel exposure) and 50 non-animal-exposed controls were examined for serological evidence of MERS-CoV infection by a pseudoparticle MERS-CoV spike protein neutralization assay. None of the sera reproducibly neutralized the MERS-CoV-pseudotyped lentiviral vector. These data suggest that serological evidence of zoonotic transmission of MERS-CoV was not common among animal workers in Southern Saudi Arabia during July 2012. PMID:25470665
Garro, AG; Beltramo, DM; Alasino, RV; Leonhard, V; Heredia, V; Bianco, ID
2011-01-01
Background: We report herein a novel strategy for the preparation of protein-based nanode-livery vehicles for hydrophobic active pharmaceutical ingredients. Methods: The procedure consisted of three steps, ie, exposure of hydrophobic residues of a protein to a pH-induced partial unfolding: interaction between hydrophobic residues on the protein and the hydrophobic active pharmaceutical ingredient, and a final step where the structure of the protein was reversed to a native-like state by returning to neutral pH. As proof of concept, the interaction of paclitaxel with partially unfolded states of human serum albumin was evaluated as a potential method for the preparation of water-soluble complexes of the taxane with albumin. Results: We found that paclitaxel readily binds to pH-induced partially unfolded albumin, leading to the formation of optically clear water-soluble complexes. The complexes thus formed were more stable in solution when the albumin native state was at least partially restored by neutralization of the solution to a pH around 7. It was also observed that the hydrodynamic radius of human serum albumin was only slightly increased after the cycle of pH changes, remaining in a monomeric state with a size according to paclitaxel binding. Furthermore, paclitaxel binding did not affect the overall exposure of charged groups of human serum albumin, as evaluated by its interaction with an ionic exchange resin. Conclusion: The in vitro biological activity of the complexes formed was qualitatively equivalent to that of a Cremophor®-based formulation. PMID:21822381
Rocha, Surza L G; Lomonte, Bruno; Neves-Ferreira, Ana G C; Trugilho, Monique R O; Junqueira-de-Azevedo, Inácio de L M; Ho, Paulo L; Domont, Gilberto B; Gutiérrez, José M; Perales, Jonas
2002-12-01
Bothrops snake venoms are known to induce local tissue damage such as hemorrhage and myonecrosis. The opossum Didelphis marsupialis is resistant to these snake venoms and has natural venom inhibitors in its plasma. The aim of this work was to clone and study the chemical, physicochemical and biological properties of DM64, an antimyotoxic protein from opossum serum. DM64 is an acidic protein showing 15% glycosylation and with a molecular mass of 63 659 Da when analysed by MALDI-TOF MS. It was cloned and the amino acid sequence was found to be homologous to DM43, a metalloproteinase inhibitor from D. marsupialis serum, and to human alpha1B-glycoprotein, indicating the presence of five immunoglobulin-like domains. DM64 neutralized both the in vivo myotoxicity and the in vitro cytotoxicity of myotoxins I (mt-I/Asp49) and II (mt-II/Lys49) from Bothrops asper venom. The inhibitor formed noncovalent complexes with both toxins, but did not inhibit the PLA2 activity of mt-I. Accordingly, DM64 did not neutralize the anticoagulant effect of mt-I nor its intracerebroventricular lethality, effects that depend on its enzymatic activity, and which demonstrate the dissociation between the catalytic and toxic activities of this Asp49 myotoxic PLA2. Furthermore, despite its similarity with metalloproteinase inhibitors, DM64 presented no antihemorrhagic activity against Bothrops jararaca or Bothrops asper crude venoms, and did not inhibit the fibrinogenolytic activity of jararhagin or bothrolysin. This is the first report of a myotoxin inhibitor with an immunoglobulin-like structure isolated and characterized from animal blood.
Liang, Bo; Surman, Sonja; Amaro-Carambot, Emerito; Kabatova, Barbora; Mackow, Natalie; Lingemann, Matthias; Yang, Lijuan; McLellan, Jason S.; Graham, Barney S.; Kwong, Peter D.; Schaap-Nutt, Anne; Collins, Peter L.
2015-01-01
ABSTRACT Respiratory syncytial virus (RSV) and human parainfluenza virus type 3 (HPIV3) are the first and second leading viral agents of severe respiratory tract disease in infants and young children worldwide. Vaccines are not available, and an RSV vaccine is particularly needed. A live attenuated chimeric recombinant bovine/human PIV3 (rB/HPIV3) vector expressing the RSV fusion (F) glycoprotein from an added gene has been under development as a bivalent vaccine against RSV and HPIV3. Previous clinical evaluation of this vaccine candidate suggested that increased genetic stability and immunogenicity of the RSV F insert were needed. This was investigated in the present study. RSV F expression was enhanced 5-fold by codon optimization and by modifying the amino acid sequence to be identical to that of an early passage of the original clinical isolate. This conferred a hypofusogenic phenotype that presumably reflects the original isolate. We then compared vectors expressing stabilized prefusion and postfusion versions of RSV F. In a hamster model, prefusion F induced increased quantity and quality of RSV-neutralizing serum antibodies and increased protection against wild-type (wt) RSV challenge. In contrast, a vector expressing the postfusion F was less immunogenic and protective. The genetic stability of the RSV F insert was high and was not affected by enhanced expression or the prefusion or postfusion conformation of RSV F. These studies provide an improved version of the previously well-tolerated rB/HPIV3-RSV F vaccine candidate that induces a superior RSV-neutralizing serum antibody response. IMPORTANCE Respiratory syncytial virus (RSV) and human parainfluenza virus type 3 (HPIV3) are two major causes of pediatric pneumonia and bronchiolitis. The rB/HPIV3 vector expressing RSV F protein is a candidate bivalent live vaccine against HPIV3 and RSV. Previous clinical evaluation indicated the need to increase the immunogenicity and genetic stability of the RSV F insert. Here, we increased RSV F expression by codon optimization and by modifying the RSV F amino acid sequence to conform to that of an early passage of the original isolate. This resulted in a hypofusogenic phenotype, which likely represents the original phenotype before adaptation to cell culture. We also included stabilized versions of prefusion and postfusion RSV F protein. Prefusion RSV F induced a larger quantity and higher quality of RSV-neutralizing serum antibodies and was highly protective. This provides an improved candidate for further clinical evaluation. PMID:26157122
Liang, Bo; Surman, Sonja; Amaro-Carambot, Emerito; Kabatova, Barbora; Mackow, Natalie; Lingemann, Matthias; Yang, Lijuan; McLellan, Jason S; Graham, Barney S; Kwong, Peter D; Schaap-Nutt, Anne; Collins, Peter L; Munir, Shirin
2015-09-01
Respiratory syncytial virus (RSV) and human parainfluenza virus type 3 (HPIV3) are the first and second leading viral agents of severe respiratory tract disease in infants and young children worldwide. Vaccines are not available, and an RSV vaccine is particularly needed. A live attenuated chimeric recombinant bovine/human PIV3 (rB/HPIV3) vector expressing the RSV fusion (F) glycoprotein from an added gene has been under development as a bivalent vaccine against RSV and HPIV3. Previous clinical evaluation of this vaccine candidate suggested that increased genetic stability and immunogenicity of the RSV F insert were needed. This was investigated in the present study. RSV F expression was enhanced 5-fold by codon optimization and by modifying the amino acid sequence to be identical to that of an early passage of the original clinical isolate. This conferred a hypofusogenic phenotype that presumably reflects the original isolate. We then compared vectors expressing stabilized prefusion and postfusion versions of RSV F. In a hamster model, prefusion F induced increased quantity and quality of RSV-neutralizing serum antibodies and increased protection against wild-type (wt) RSV challenge. In contrast, a vector expressing the postfusion F was less immunogenic and protective. The genetic stability of the RSV F insert was high and was not affected by enhanced expression or the prefusion or postfusion conformation of RSV F. These studies provide an improved version of the previously well-tolerated rB/HPIV3-RSV F vaccine candidate that induces a superior RSV-neutralizing serum antibody response. Respiratory syncytial virus (RSV) and human parainfluenza virus type 3 (HPIV3) are two major causes of pediatric pneumonia and bronchiolitis. The rB/HPIV3 vector expressing RSV F protein is a candidate bivalent live vaccine against HPIV3 and RSV. Previous clinical evaluation indicated the need to increase the immunogenicity and genetic stability of the RSV F insert. Here, we increased RSV F expression by codon optimization and by modifying the RSV F amino acid sequence to conform to that of an early passage of the original isolate. This resulted in a hypofusogenic phenotype, which likely represents the original phenotype before adaptation to cell culture. We also included stabilized versions of prefusion and postfusion RSV F protein. Prefusion RSV F induced a larger quantity and higher quality of RSV-neutralizing serum antibodies and was highly protective. This provides an improved candidate for further clinical evaluation. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Frequency Spectrum Neutrality Tests: One for All and All for One
Achaz, Guillaume
2009-01-01
Neutrality tests based on the frequency spectrum (e.g., Tajima's D or Fu and Li's F) are commonly used by population geneticists as routine tests to assess the goodness-of-fit of the standard neutral model on their data sets. Here, I show that these neutrality tests are specific instances of a general model that encompasses them all. I illustrate how this general framework can be taken advantage of to devise new more powerful tests that better detect deviations from the standard model. Finally, I exemplify the usefulness of the framework on SNP data by showing how it supports the selection hypothesis in the lactase human gene by overcoming the ascertainment bias. The framework presented here paves the way for constructing novel tests optimized for specific violations of the standard model that ultimately will help to unravel scenarios of evolution. PMID:19546320
Viral Vaccine Immunogenicity in Relation to Host Cell-Mediated and Humoral Immune Responses.
1976-05-01
adjuvants, particularly complete Freund’s adjuvant or Bordetella pertussis , were donors capable of consistently transferring adoptive immunity...vac- cine combined with adjuvants, particularly complete Freund’s adjuvant or Bordetella pertussis , were donors capable of consistently transferring...Freund’s adjuvant and Bordetella pertussis , are consistently capable of producing early and brisk serum neutralizing antibody responses in adoptively
Schlaudecker, Elizabeth P; Steinhoff, Mark C; Omer, Saad B; McNeal, Monica M; Roy, Eliza; Arifeen, Shams E; Dodd, Caitlin N; Raqib, Rubhana; Breiman, Robert F; Zaman, K
2013-01-01
Antenatal immunization of mothers with influenza vaccine increases serum antibodies and reduces the rates of influenza illness in mothers and their infants. We report the effect of antenatal immunization on the levels of specific anti-influenza IgA levels in human breast milk. (ClinicalTrials.gov identifier NCT00142389; http://clinicaltrials.gov/ct2/show/NCT00142389). The Mother's Gift study was a prospective, blinded, randomized controlled trial that assigned 340 pregnant Bangladeshi mothers to receive either trivalent inactivated influenza vaccine, or 23-valent pneumococcal polysaccharide vaccine during the third trimester. We evaluated breast milk at birth, 6 weeks, 6 months, and 12 months, and serum at 10 weeks and 12 months. Milk and serum specimens from 57 subjects were assayed for specific IgA antibody to influenza A/New Caledonia (H1N1) using an enzyme-linked immunosorbent assay (ELISA) and a virus neutralization assay, and for total IgA using ELISA. Influenza-specific IgA levels in breast milk were significantly higher in influenza vaccinees than in pneumococcal controls for at least 6 months postpartum (p = 0.04). Geometric mean concentrations ranged from 8.0 to 91.1 ELISA units/ml in vaccinees, versus 2.3 to 13.7 ELISA units/mL in controls. Virus neutralization titers in milk were 1.2 to 3 fold greater in vaccinees, and correlated with influenza-specific IgA levels (r = 0.86). Greater exclusivity of breastfeeding in the first 6 months of life significantly decreased the expected number of respiratory illness with fever episodes in infants of influenza-vaccinated mothers (p = 0.0042) but not in infants of pneumococcal-vaccinated mothers (p = 0.4154). The sustained high levels of actively produced anti-influenza IgA in breast milk and the decreased infant episodes of respiratory illness with fever suggest that breastfeeding may provide local mucosal protection for the infant for at least 6 months. Studies are needed to determine the cellular and immunologic mechanisms of breast milk-mediated protection after antepartum immunization. ClinicalTrials.gov NCT00142389.
A polyvalent inactivated rhinovirus vaccine is broadly immunogenic in rhesus macaques
Lee, Sujin; Nguyen, Minh Trang; Currier, Michael G.; Jenkins, Joe B.; Strobert, Elizabeth A.; Kajon, Adriana E.; Madan-Lala, Ranjna; Bochkov, Yury A.; Gern, James E.; Roy, Krishnendu; Lu, Xiaoyan; Erdman, Dean D.; Spearman, Paul; Moore, Martin L.
2016-01-01
As the predominant aetiological agent of the common cold, human rhinovirus (HRV) is the leading cause of human infectious disease. Early studies showed that a monovalent formalin-inactivated HRV vaccine can be protective, and virus-neutralizing antibodies (nAb) correlated with protection. However, co-circulation of many HRV types discouraged further vaccine efforts. Here, we test the hypothesis that increasing virus input titres in polyvalent inactivated HRV vaccine may result in broad nAb responses. We show that serum nAb against many rhinovirus types can be induced by polyvalent, inactivated HRVs plus alhydrogel (alum) adjuvant. Using formulations up to 25-valent in mice and 50-valent in rhesus macaques, HRV vaccine immunogenicity was related to sufficient quantity of input antigens, and valency was not a major factor for potency or breadth of the response. Thus, we have generated a vaccine capable of inducing nAb responses to numerous and diverse HRV types. PMID:27653379
Characterization of anemia induced by avian osteopetrosis virus.
Paterson, R W; Smith, R E
1978-01-01
Chickens infected intravenously at 8 days after hatching with an avian osteopetrosis virus developed a severe, progressive anemia in the absence of osteopetrosis. The anemia was characterized as a pancytopenia, in which erythrocytes, granulocytes, and thrombocytes decreased concomitantly. Serum bilirubin levels were normal, whereas erythrocytes from infected chickens demonstrated a slightly elevated osmotic fragility. A negative Coombs test indicated that there was no evidence for erythrocyte-bound antibody. Erythrocytes from infected animals had slightly decreased 51Cr-labeled erythrocyte survival time when compared with normal. Examination of marrow histological preparations, together with ferrokinetic studies with 59Fe, indicated that marrow failure occurred during the acute phase of the anemia. Circulating virus was present during the development and acute phases of the anemia, but disappeared during the recovery phase of the disease. Neutralizing antibody appeared after the disappearance of circulating virus. It is concluded that virus infection induced both marrow failure (aplastic crisis) and decreased erythrocyte survival. Images PMID:215554
Du, E; Xiao, L; Hurley, M M
2017-03-01
High molecular weight FGF2 transgenic mice (HMWTg) phenocopy the Hyp mouse, homolog of human X-linked hypophosphatemic rickets with phosphate wasting and abnormal fibroblast growth factor (FGF23), fibroblast growth factor receptor (FGFR), Klotho and mitogen activated protein kinases (MAPK) signaling in kidney. In this study, we assessed whether short-term (24 h) in vivo administration of FGF23 neutralizing antibody (FGF23Ab) could rescue hypophosphatemia and impaired FGFR signaling in kidneys of HMWTg male mice. Bone mineral density and bone mineral content in 1-month-old HMWTg mice were significantly reduced compared with Control/VectorTg mice. Serum FGF23 was significantly increased in HMWTg compared with VectorTg. Serum phosphate was significantly reduced in HMWTg and was rescued by FGF23Ab. Serum parathyroid hormone (PTH) was significantly increased in HMWTg but was not reduced by FGF23Ab. 1, 25(OH) 2 D was inappropriately normal in serum of HMWTg and was significantly increased in both Vector and HMWTg by FGF23Ab. Analysis of HMWTg kidneys revealed significantly increased mRNA expression of the FGF23 co-receptor Klotho, transcription factor mRNAs for early growth response-1 transcription factor (Egr-1), and c-fos were all significantly decreased by FGF23Ab. A significant reduction in the phosphate transporter Npt2a mRNA was also observed in HMWTg kidneys, which was increased by FGF23Ab. FGF23Ab reduced p-FGFR1, p-FGFR3, KLOTHO, p-ERK1/2, C-FOS, and increased NPT2A protein in HMWTg kidneys. We conclude that FGF23 blockade rescued hypophosphatemia by regulating FGF23/FGFR downstream signaling in HMWTg kidneys. Furthermore, HMWFGF2 isoforms regulate PTH expression independent of FGF23/FGFR signaling. J. Cell. Physiol. 232: 610-616, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Longbottom, E Rebecca; Torrance, Hew D T; Owen, Helen C; Fragkou, Paraskevi C; Hinds, Charles J; Pearse, Rupert M; O'Dwyer, Michael J
2016-08-01
The aim of this study was to evaluate the role of interleukin (IL)-6 pathways in postoperative immune suppression and to assess the reversibility of this phenomenon. The postoperative period is characterized by increased IL-6 production and features of immune suppression. In vitro, IL-6 mediates anti-inflammatory effects through inhibition of interferon gamma (IFN-γ) pathways. The significance of the immunomodulatory effects of IL-6 in the clinical setting of postoperative immune suppression remains unclear. Patients over 45 years old undergoing elective surgery, involving the gastrointestinal tract, were recruited. IL-6 levels were assayed using an enzyme linked immunosorbent assay preoperatively, and at 24 and 48 hours. Peripheral blood mononuclear cells from healthy volunteers were cultured in perioperative serum and CD14Human Leukocyte Antigen-DR (HLA-DR) [monocyte HLA-DR (mHLA-DR)] geometric mean florescent intensity was measured in the presence and absence of IL-6 neutralizing antibody and recombinant IFN-γ. Of the 108 patients, 41 developed a postoperative infection. The IL-6 levels increased 19-fold from the preoperative sample to 24 hours postoperatively (P < 0.0001). Higher IL-6 levels at 24 (P = 0.0002) and 48 hours (P = 0.003) were associated with subsequent postoperative infectious complications. mHLA-DR mean florescent intensity fell when healthy peripheral blood mononuclear cells were cultured with postoperative serum compared with preoperative serum (P = 0.008). This decrease was prevented by the presence of IFN-γ in the culture media, but not by the presence of IL-6-neutralizing antibody. IL-6 levels increase after a major surgery and are associated with an increased susceptibility to postoperative infections. Serum obtained from postoperative patients induces an immunosuppressive response, reflected in reduced mHLA-DR levels, mediated through IL-6 independent pathways and is reversible with IFN-γ. These data may have therapeutic implications for the prevention of infection in patients undergoing major surgery.
Amog, P U; Manjuprasanna, V N; Yariswamy, M; Nanjaraj Urs, A N; Joshi, Vikram; Suvilesh, K N; Nataraju, A; Vishwanath, Bannikuppe Sannanaik; Gowda, T V
2016-11-01
Viperid venom-induced chronic local-toxicity continues even after anti-snake venom treatment. Therefore, traditional antidote Albizia lebbeck L. (Fabaceae) seed extract was tested against Echis carinatus S. (Viperidae) venom (ECV)-induced local toxicity to evaluate its complementary remedy. Soxhlet extraction of A. lebbeck seeds was performed with the increasing polarity of solvents (n-hexane to water); the extract was screened for phytochemicals (alkaloids, anthraquinones, flavonoids, glycosides, phenolics, saponins, steroids and tannins). In preliminary in vitro analysis, A. lebbeck methanolic extract (ALME) demonstrated significant inhibition of ECV proteases, the major enzyme-toxin responsible for local- toxicity. Therefore, in vitro neutralizing potential of ALME was further evaluated against hyaluronidases and phospholipase A 2 (1:1-1:100 w/w). In addition, alleviation of ECV induced characteristic local- toxicity [haemorrhage (i.d.) and myotoxicity (i.m.)] was determined in mice. ALME contained high concentrations of phenolics and flavonoids and demonstrated significant in vitro inhibition of ECV protease (IC 50 = 36.32 μg, p < 0.0001) and hyaluronidase (IC 50 = 91.95 μg, p < 0.0001) at 1:100 w/w. ALME significantly neutralized ECV induced haemorrhage (ED 50 = 26.37 μg, p < 0.0001) and myotoxicity by significantly reducing serum creatinine kinase (ED 50 = 37.5 μg, p < 0.0001) and lactate dehydrogenase (ED 50 = 31.44 μg, p = 0.0021) levels at 1:50 w/w. ALME demonstrated significant neutralization of ECV enzymes that contribute in local tissue damage and haemostatic alterations. The study scientifically supports the anecdotal use of A. lebbeck in complementary medicine and identifies ALME as principle fraction responsible for antivenom properties.
Russell, Elizabeth S.; Kwiek, Jesse J.; Keys, Jessica; Barton, Kirston; Mwapasa, Victor; Montefiori, David C.; Meshnick, Steven R.; Swanstrom, Ronald
2011-01-01
Subtype C human immunodeficiency virus type 1 (HIV-1C) continues to cause the majority of new cases of mother-to-child transmission (MTCT), and yet there are limited data on HIV-1C transmission. We amplified env from plasma RNA for 19 HIV-1C MTCT pairs, 10 transmitting in utero (IU) and 9 transmitting intrapartum (IP). There was a strong genetic bottleneck between all mother-infant pairs, with a majority of transmission events involving the transmission of a single virus. env genes of viruses transmitted to infants IP, but not IU, encoded Env proteins that were shorter and had fewer putative N-linked glycosylation sites in the V1-V5 region than matched maternal sequences. Viruses pseudotyped with env clones representative of each maternal and infant population were tested for neutralization sensitivity. The 50% inhibitory concentration of autologous serum was similar against both transmitted (infant) and nontransmitted (maternal) viruses in a paired analysis. Mother and infant Env proteins were also similar in sensitivity to soluble CD4, to a panel of monoclonal antibodies, and to heterologous HIV-1C sera. In addition, there was no difference in the breadth or potency of neutralizing antibodies between sera from 50 nontransmitting and 23 IU and 23 IP transmitting HIV-1C-infected women against four Env proteins from heterologous viruses. Thus, while a strong genetic bottleneck was detected during MCTC, with viruses of shorter and fewer glycosylation sites in env present in IP transmission, our data do not support this bottleneck being driven by selective resistance to antibodies. PMID:21593171
Williams, John D; Topley, Nicholas; Craig, Kathrine J; Mackenzie, Ruth K; Pischetsrieder, Monika; Lage, Cristina; Passlick-Deetjen, Jutta
2004-07-01
Although peritoneal dialysis (PD) is a widely accepted form of renal replacement therapy (RRT), concerns remain regarding the bioincompatible nature of standard PD fluid. In order to evaluate whether a newly formulated fluid of neutral pH, and containing low levels of glucose degradation products (GDP), resulted in improved in vivo biocompatibility, it was compared in a clinical study to a standard PD fluid. In a multicenter, open, randomized, prospective study with a crossover design and parallel arms, a conventional, acidic, lactate-buffered fluid (SPDF) was compared with a pH neutral, lactate-buffered, low GDP fluid (balance). Overnight effluent was collected and assayed for cancer antigen 125 (CA125), hyaluronic acid (HA), procollagen peptide (PICP), vascular endothelial growth factor (VEGF), and tumor necrosis factor alpha (TNFalpha). Serum samples were assayed for circulating advanced glycosylation end products (AGE), N(epsilon)-(carboxymethyl)lysine (CML), and imidazolone. Clinical end points were residual renal function (RRF), adequacy of dialysis, ultrafiltration, and peritoneal membrane function. Eighty-six patients were randomized to either group I starting with SPDF for 12 weeks (Phase I), then switching to "balance" for 12 weeks (Phase II), or group II, which was treated vice versa. Seventy-one patients completed the study with data suitable for entry into the per protocol analysis. Effluent and serum samples, together with peritoneal function tests and adequacy measurements, were undertaken at study centers on three occasions during the study: after the four-week run-in period, after Phase I, and again after Phase II. In patients treated with balance there were significantly higher effluent levels of CA125 and PICP in both arms of the study. Conversely, levels of HA were lower in patients exposed to balance, while there was no change in the levels of either VEGF or TNFalpha. Serum CML and imidazolone levels fell significantly in balance-treated patients. Renal urea and creatinine clearances were higher in both treatment arms after patients were exposed to balance. Urine volume was higher in patients exposed to balance. In contrast, peritoneal ultrafiltration was higher in patients on SPDF. When anuric patients were analyzed as a subgroup, there was no significant difference in peritoneal transport characteristics or in ultrafiltration on either fluid. There were no changes in peritonitis incidence on either solution. This study indicates that the use of balance, a neutral pH, low GDP fluid, is accompanied by a significant improvement in effluent markers of peritoneal membrane integrity and significantly decreased circulating AGE levels. Clinical parameters suggest an improvement in residual renal function on balance, with an accompanying decrease in peritoneal ultrafiltration. It would appear that balance solution results in an improvement in local peritoneal homeostasis, as well as having a positive impact on systemic parameters, including circulating AGE and residual renal function.
Japolla, Greice; Cunha-Junior, Jair Pereira; Pajuaba, Ana Claudia Arantes Marquez; Taketomi, Ernesto Akio; Bührer-Sékula, Samira; Bataus, Luiz Artur Mendes; de Souza, Guilherme Rocha Lino
2018-06-01
Bovine herpesvirus type 1 (BoHV-1) is recognized as an important pathogen causing respiratory, reproductive, and neurological disorders in cattle and is associated with economic losses to animal industry. Accurate diagnostic methods are needed for prevention of disease transmission. While the virus neutralization test is considered the gold standard method, it requires maintenance of the virus and cell cultures, which is time consuming and expensive. Serological techniques such as enzyme-linked immunosorbent assay (ELISA) are widely applied, as these are easy to perform and provide quick results. In the present study, a nanogold slot blot inhibition assay was developed for the serological diagnosis of BoHV-1 and compared with standard ELISA and horseradish peroxidase (HRP) slot blot assays. Of 42 serum samples tested by ELISA, 32 (76.2%) were positive and 10 (23.8%), were negative. The sensitivity and specificity of the nanogold slot blot inhibition assay was similar to that observed for ELISA and HRP slot blot assays, and a strong correlation was observed between the tests. Thus, the nanogold slot blot inhibition assay may serve as an efficient and rapid alternative to ELISA in settings, where plate-reading equipment is lacking.
Zhai, Yougang; Zhong, Zhenyu; Zariffard, Mohammadreza; Spear, Gregory T.; Qiao, Liang
2013-01-01
Two conserved epitopes, located in the membrane-proximal external region (MPER) of the human immunodeficiency virus type 1 (HIV-1) gp41, are recognized by two HIV-1 broadly neutralizing antibodies 2F5 and 4E10, and are promising targets for vaccine design in efforts to elicit anti-HIV-1 broadly neutralizing antibodies. Since most HIV-1 infections initiate at mucosal surfaces, induction of mucosal neutralizing antibodies is necessary and of utmost importance to counteract HIV-1 infection. Here, we utilized a mucosal vaccine vector, bovine papillomavirus (BPV) virus-like particles (VLPs), as a platform to present HIV-1 neutralizing epitopes by inserting the extended 2F5 or 4E10 epitope or the MPER domain into D-E loop of BPV L1 respectively. The chimeric VLPs presenting MPER domain resembled the HIV-1 natural epitopes better than the chimeric VLPs presenting single epitopes. Oral immunization of mice with the chimeric VLPs displaying the 2F5 epitope or MPER domain elicited epitope-specific serum IgGs and mucosal secretory IgAs. The induced antibodies specifically recognized the native conformation of MPER in the context of HIV-1 envelope protein. The antibodies induced by chimeric VLPs presenting MPER domain are able to partially neutralize HIV-1 viruses from clade B and clade C. PMID:24055348
Effects of hydration on steric and electric charge-induced interstitial volume exclusion--a model.
Øien, Alf H; Justad, Sigrid R; Tenstad, Olav; Wiig, Helge
2013-09-03
The presence of collagen and charged macromolecules like glycosaminoglycans (GAGs) in the interstitial space limits the space available for plasma proteins and other macromolecules. This phenomenon, known as interstitial exclusion, is of importance for interstitial fluid volume regulation. Physical/mathematical models are presented for calculating the exclusion of electrically charged and neutral macromolecules that equilibrate in the interstitium under various degrees of hydration. Here, a central hypothesis is that the swelling of highly electrically charged GAGs with increased hydration shields parts of the neutral collagen of the interstitial matrix from interacting with electrically charged macromolecules, such that exclusion of charged macromolecules exhibits change due to steric and charge effects. GAGs are also thought to allow relatively small neutral, but also charged macromolecules neutralized by a very high ionic strength, diffuse into the interior of GAGs, whereas larger macromolecules may not. Thus, in the model, relatively small electrically charged macromolecules, such as human serum albumin, and larger neutral macromolecules such as IgG, will have quite similar total volume exclusion properties in the interstitium. Our results are in agreement with ex vivo and in vivo experiments, and suggest that the charge of GAGs or macromolecular drugs may be targeted to increase the tissue uptake of macromolecular therapeutic agents. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.
Antibodyomics: bioinformatics technologies for understanding B-cell immunity to HIV-1.
Kwong, Peter D; Chuang, Gwo-Yu; DeKosky, Brandon J; Gindin, Tatyana; Georgiev, Ivelin S; Lemmin, Thomas; Schramm, Chaim A; Sheng, Zizhang; Soto, Cinque; Yang, An-Suei; Mascola, John R; Shapiro, Lawrence
2017-01-01
Numerous antibodies have been identified from HIV-1-infected donors that neutralize diverse strains of HIV-1. These antibodies may provide the basis for a B cell-mediated HIV-1 vaccine. However, it has been unclear how to elicit similar antibodies by vaccination. To address this issue, we have undertaken an informatics-based approach to understand the genetic and immunologic processes controlling the development of HIV-1-neutralizing antibodies. As DNA sequencing comprises the fastest growing database of biological information, we focused on incorporating next-generation sequencing of B-cell transcripts to determine the origin, maturation pathway, and prevalence of broadly neutralizing antibody lineages (Antibodyomics1, 2, 4, and 6). We also incorporated large-scale robotic analyses of serum neutralization to identify and quantify neutralizing antibodies in donor cohorts (Antibodyomics3). Statistical analyses furnish another layer of insight (Antibodyomics5), with physical characteristics of antibodies and their targets through molecular dynamics simulations (Antibodyomics7) and free energy perturbation analyses (Antibodyomics8) providing information-rich output. Functional interrogation of individual antibodies (Antibodyomics9) and synthetic antibody libraries (Antibodyomics10) also yields multi-dimensional data by which to understand and improve antibodies. Antibodyomics, described here, thus comprise resolution-enhancing tools, which collectively embody an information-driven discovery engine aimed toward the development of effective B cell-based vaccines. © 2017 The Authors. Immunological Reviews published by John Wiley & Sons Ltd.
Wang, Joshua W; Jagu, Subhashini; Wang, Chenguang; Kitchener, Henry C; Daayana, Sai; Stern, Peter L; Pang, Susana; Day, Patricia M; Huh, Warner K; Roden, Richard B S
2014-01-01
Antibodies specific for neutralizing epitopes in either Human papillomavirus (HPV) capsid protein L1 or L2 can mediate protection from viral challenge and thus their accurate and sensitive measurement at high throughput is likely informative for monitoring response to prophylactic vaccination. Here we compare measurement of L1 and L2-specific neutralizing antibodies in human sera using the standard Pseudovirion-Based Neutralization Assay (L1-PBNA) with the newer Furin-Cleaved Pseudovirion-Based Neutralization Assay (FC-PBNA), a modification of the L1-PBNA intended to improve sensitivity towards L2-specific neutralizing antibodies without compromising assay of L1-specific responses. For detection of L1-specific neutralizing antibodies in human sera, the FC- PBNA and L1-PBNA assays showed similar sensitivity and a high level of correlation using WHO standard sera (n = 2), and sera from patients vaccinated with Gardasil (n = 30) or an experimental human papillomavirus type 16 (HPV16) L1 VLP vaccine (n = 70). The detection of L1-specific cross-neutralizing antibodies in these sera using pseudovirions of types phylogenetically-related to those targeted by the L1 virus-like particle (VLP) vaccines was also consistent between the two assays. However, for sera from patients (n = 17) vaccinated with an L2-based immunogen (TA-CIN), the FC-PBNA was more sensitive than the L1-PBNA in detecting L2-specific neutralizing antibodies. Further, the neutralizing antibody titers measured with the FC-PBNA correlated with those determined with the L2-PBNA, another modification of the L1-PBNA that spacio-temporally separates primary and secondary receptor engagement, as well as the protective titers measured using passive transfer studies in the murine genital-challenge model. In sum, the FC-PBNA provided sensitive measurement for both L1 VLP and L2-specific neutralizing antibody in human sera. Vaccination with TA-CIN elicits weak cross-protective antibody in a subset of patients, suggesting the need for an adjuvant.
Reich, Kristian; Jackson, Kimberley; Ball, Susan; Garces, Sandra; Kerr, Lisa; Chua, Laiyi; Muram, Talia M; Blauvelt, Andrew
2018-05-08
Ixekizumab, a high-affinity monoclonal antibody that selectively targets interleukin-17A, is efficacious for moderate-to-severe plaque psoriasis. We examined relationships between serum ixekizumab concentrations, treatment-emergent anti-drug antibodies (TE-ADA), and efficacy during 60 weeks of treatment in a randomized, controlled, phase 3 study. Steady-state ixekizumab serum trough concentrations were rapidly achieved and associated with high clinical responses at week 12 with a starting dose of 160 mg followed by 80 mg every 2 weeks. During the long-term extension period dosing at 80 mg every 4 weeks, stable serum trough concentrations maintained high clinical responses through week 60. Most (82.6%, 308/373) patients never developed TE-ADA. In TE-ADA-positive patients (17.4%, n=65), variations in ADA titers, neutralizing capacity, and persistence were observed. Fifty-six patients (15%) developed low or moderate maximum titers, with serum concentrations and efficacy comparable to TE-ADA-negative patients. Nine patients (2.4%) developed high titers with variable individual clinical responses; four of these nine patients achieved at least PASI 75 at week 60. Median serum concentrations in the TE-ADA-high titer group were generally comparable to the median serum concentrations in the lower titer groups. For most patients, TE-ADA had a negligible impact on ixekizumab serum concentrations and efficacy. Clinicaltrials.gov: NCT01646177. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.
Radi, Zaher A; Koza-Taylor, Petra H; Bell, Rosonald R; Obert, Leslie A; Runnels, Herbert A; Beebe, Jean S; Lawton, Michael P; Sadis, Seth
2011-07-01
Macrophage colony-stimulating factor (M-CSF) is a hematopoietic growth factor that is responsible for the survival and proliferation of monocytes and the differentiation of monocytes into macrophages, including Kupffer cells (KCs) in the liver. KCs play an important role in the clearance of several serum enzymes, including aspartate aminotransferase and creatine kinase, that are typically elevated as a result of liver or skeletal muscle injury. We used three distinct animal models to investigate the hypothesis that increases in the levels of serum enzymes can be the result of decreases in KCs in the apparent absence of hepatic or skeletal muscle injury. Specifically, neutralizing M-CSF activity via a novel human monoclonal antibody reduced the CD14(+)CD16(+) monocyte population, depleted KCs, and increased aspartate aminotransferase and creatine kinase serum enzyme levels in cynomolgus macaques. In addition, the treatment of rats with clodronate liposomes depleted KCs and led to increased serum enzyme levels, again without evidence of tissue injury. Finally, in the osteopetrotic (Csf1(op)/Csf1(op)) mice lacking functional M-CSF and having reduced levels of KCs, the levels of serum enzymes are higher than in wild-type littermates. Together, these findings support a mechanism for increases in serum enzyme levels through M-CSF regulation of tissue macrophage homeostasis without concomitant histopathological changes in either the hepatic or skeletal system. Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.
Jurewicz, Anna; Domowicz, Malgorzata; Galazka, Grazyna; Raine, Cedric S; Selmaj, Krzysztof
2017-10-01
A lot of available data on lipid immunology in multiple sclerosis (MS) have been derived from studies using synthetic lipids, therefore the role of lipids in the immunopathogenesis of MS remains poorly defined. The present study on the lipid response in MS was performed on native lipids from autopsied brain tissue. For this, lipid fractions (n = 9) were prepared from MS (n = 3) and control (n = 2) white matter according to the Folch procedure and were characterized depending on their solubility in chloroform/methanol. TLC showed that, in brain from MS cases, neutral lipids were rich in cholesterol and cholesterol esters while lipids from control brains displayed a predominance of phospholipids. MS serum IgG and IgM were found to bind to MS brain lipid fractions with a higher efficacy (p < 0.05) than the control serum. F(ab) 2 fractionation revealed that MS serum IgG binding depended on a specific antibody-type of recognition. Pre-adsorption of serum with cholesterol, galactocerebrosides, sulfitides, and phosphatidylinositol prior to ELISA with MS brain lipids, showed that cholesterol diminished IgG and IgM binding up to 70%. Experiments with synthetic lipids confirmed the predominance of cholesterol binding by MS serum. Our results demonstrate that IgG and IgM fractions from MS serum specifically and predominantly recognize native cholesterol and cholesterol esters isolated from the brain tissue of patients with MS. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Soto, Francisco Rafael Martins; Pinheiro, Sônia Regina; Morais, Zenaide Maria; Gonçales, Amane Paldês; de Azevedo, Sérgio Santos; Bernardi, Fernanda; Camargo, Sebastião Rodrigues; Vasconcellos, Silvio Arruda
2008-01-01
It was performed the comparison of the intensity and duration of agglutinating and neutralizing antibodies to serovar Hardjo in swines vaccinated with two commercial anti-leptospira bacterins. Sows no reactive to 24 Leptospira sp serovars in the microscopic agglutination test (MAT) were divided in three groups: Group A (n=08): received two vaccine A doses with 30 days interval, Group B (n=08) two vaccine B doses with 30 days interval and Group C (n=08): control no vaccinated against leptospirosis.Blood samples were collected each 30 days during six months following the first vaccination. The sera were tested by MAT and growth inhibition test (GIT) to serovar Hardjo in order to evaluate respectively agglutinating and neutralizing antibodies. It was found that neutralizing antibodies persisted for a longer time than the agglutinating ones and that the absence of agglutinating antibodies does not means in the absence of the neutralizing. The peaks of agglutinating antibodies was obtained at least 30 days earlier than that produced by neutralizing. The duration of both kinds of antibodies measured differed between the two bacterines tested. The period for inducing neutralizing antibodies against serovar Hardjo indicated that gilts must be immunized with two doses of whole culture anti-leptospira bacterines applied 30 days each other at least 90 days before the first mating. For the maintenance of hight levels of neutralizing antibodies the revaccinations must be performed every six months after the first vaccination. PMID:24031250
Lymphocyte-dependent antibody-mediated cytotoxicity in Hashimoto thyroiditis
Calder, Elizabeth A.; Penhale, W. J.; McLeman, Dena; Barnes, E. W.; Irvine, W. J.
1973-01-01
In the presence of normal human lymphocytes, decomplemented sera from twentynine out of thirty-nine patients with Hashimoto thyroiditis caused significant lysis of thyroglobulin-coated chicken red blood cells, as estimated by the release of 51Cr; the mean% specific 51Cr release being 14·1 ± 1·9 (SEM). Serum from twenty-one control subjects studied concurrently caused no significant lysis of thyroglobulin-coated chicken red blood cells; the mean% specific 51Cr release being −1·6±0·7 (SEM). The degree of cytotoxicity correlated with the titre of thyroglobulin antibodies in the serum, determined by tanned red cell haemagglutination. The active component in the Hashimoto serum was localized in the 19S fraction, was unaffected by pre-absorption with anti-human IgM serum, but was neutralized by pre-absorption with anti-human IgG serum. These findings suggest that the cytotoxic activity of serum from patients with Hashimoto thyroiditis is due to the presence of thyroglobulin antibody of the IgG class in the form of complexes, either alone or with antigen. It is postulated that non-specific lymphocytes may play an important role in the pathogenesis of Hashimoto thyroiditis, being activated by the presence in the gland of thyroglobulin antibody, either alone or in the form of complexes attached to thyroid cells. PMID:4740445
Seino, H; Satoh, J; Shintani, S; Takahashi, K; Zhu, X P; Masuda, T; Nobunaga, T; Saito, M; Terano, Y; Toyota, T
1991-01-01
We have recently reported that systemic and chronic administration of recombinant tumour necrosis factor alpha (TNF-alpha), as well as streptococcal preparation (OK-432), inhibits development of insulin-dependent diabetes mellitus (IDDM) in NOD mice and BB rats, models of IDDM. In this study we examined whether serum containing endogenous TNF induced by OK-432 injection could inhibit IDDM in NOD mice. Treatment twice a week from 4 weeks of age with OK-432-injected mouse serum, which contained endogenous TNF (75U), but not IL-1, IL-2 and interferon-gamma (IFN-gamma) activity, reduced the intensity of insulitis and significantly inhibited the cumulative incidence of diabetes by 28 weeks of age in NOD mice, as compared with the incidence in non-treated mice (P less than 0.01) and in mice treated with control serum (P less than 0.02). This inhibitory effect of the serum was diminished, although not significantly, by neutralization of serum TNF activity with anti-mouse TNF antibody. In the mice treated with the serum from OK-432-injected mice, Thy-1.2+ or CD8+ spleen cells decreased (P less than 0.01) and surface-Ig+ (S-Ig+) cells increased (P less than 0.05), whereas the proliferative response of spleen cells to concanavalin A (P less than 0.01) and lipopolysaccharide (P less than 0.05) increased. The results indicate that the inhibition by OK-432 treatment of IDDM in NOD mice was partially mediated by serum factors including endogenous TNF. PMID:1747949
SINGLE- VERSUS DOUBLE-DOSE RABIES VACCINATION IN CAPTIVE AFRICAN WILD DOGS (LYCAON PICTUS).
Connolly, Maren; Thomas, Patrick; Woodroffe, Rosie; Raphael, Bonnie L
2015-12-01
The immune responses of 35 captive African wild dogs (Lycaon pictus) to an inactivated rabies virus vaccine were evaluated. Seventeen animals received one 1-ml dose of inactivated rabies vaccine administered intramuscularly, while 18 received two 1-ml doses given simultaneously but at different injection sites. Sera were collected from all animals prior to vaccination and intermittently from a subset of animals between 3 and 49 mo postvaccination. Rabies neutralizing serum antibody titers were measured by rapid fluorescent focus inhibition testing. Within 3 mo postvaccination, all 28 animals that were tested within that time period had seroconverted. Overall, titers were significantly higher among animals given two doses of vaccine than among those given a single dose, although this difference was no longer significant by 15 mo postvaccination. Regardless of initial dose, a single administration of inactivated rabies virus vaccine resulted in long-term elevation of titers in the African wild dogs in this study. In the two individuals followed for greater than 36 mo, both (one from each group) maintained detectable titers.
Diotti, Roberta Antonia; Mancini, Nicasio; Clementi, Nicola; Sautto, Giuseppe; Moreno, Guisella Janett; Criscuolo, Elena; Cappelletti, Francesca; Man, Petr; Forest, Eric; Remy, Louise; Giannecchini, Simone; Clementi, Massimo; Burioni, Roberto
2014-08-01
JC virus (JCPyV) has gained novel clinical importance as cause of progressive multifocal leukoencephalopathy (PML), a rare demyelinating disease recently associated to immunomodulatory drugs, such as natalizumab used in multiple sclerosis (MS) cases. Little is known about the mechanisms leading to PML, and this makes the need of PML risk stratification among natalizumab-treated patients very compelling. Clinical and laboratory-based risk-stratification markers have been proposed, one of these is represented by the JCPyV-seropositive status, which includes about 54% of MS patients. We recently proposed to investigate the possible protective role of neutralizing humoral immune response in preventing JCPyV reactivation. In this proof-of-concept study, by cloning the first human monoclonal antibody (GRE1) directed against a neutralizing epitope on JCPyV/VP1, we optimized a robust anti-JCPyV neutralization assay. This allowed us to evaluate the neutralizing activity in JCPyV-positive sera from MS patients, demonstrating the lack of correlation between the level of anti-JCPyV antibody and anti-JCPyV neutralizing activity. Relevant consequences may derive from future clinical studies induced by these findings; indeed the study of the serum anti-JCPyV neutralizing activity could allow not only a better risk stratification of the patients during natalizumab treatment, but also a better understanding of the pathophysiological mechanisms leading to PML, highlighting the contribution of peripheral versus central nervous system JCPyV reactivation. Noteworthy, the availability of GRE1 could allow the design of novel immunoprophylactic strategies during the immunomodulatory treatment. Copyright © 2014 Elsevier B.V. All rights reserved.
Verma, Harish; Sharma, Prashant; Yang, Jae Seung; Saletti, Giulietta; Ahmad, Mohammad; Bahl, Sunil K.; Wierzba, Thomas F.; Nandy, Ranjan K.; Deshpande, Jagadish M.; Sutter, Roland W.; Czerkinsky, Cecil
2016-01-01
Background The “gold standard” for assessing mucosal immunity after vaccination with poliovirus vaccines consists in measuring virus excretion in stool after challenge with oral poliovirus vaccine (OPV). This testing is time and resource intensive, and development of alternative methods is a priority for accelerating polio eradication. We therefore evaluated circulating antibody-secreting cells (ASCs) as a potential means to evaluate mucosal immunity to poliovirus vaccine. Methods 199 subjects, aged 10 years, and previously immunized repeatedly with OPV, were selected. Subjects were assigned to receive either a booster dose of inactivated poliovirus vaccine (IPV), bivalent OPV (bOPV), or no vaccine. Using a micro-modified whole blood-based ELISPOT assay designed for field setting, circulating poliovirus type-specific IgA- and IgG-ASCs, including gut homing α4β7+ ASCs, were enumerated on days 0 and 7 after booster immunization. In addition, serum samples collected on days 0, 28 and 56 were tested for neutralizing antibody titers against poliovirus types 1, 2, and 3. Stool specimens were collected on day 28 (day of bOPV challenge), and on days 31, 35 and 42 and processed for poliovirus isolation. Results An IPV dose elicited blood IgA- and IgG-ASC responses in 84.8 to 94.9% of subjects, respectively. In comparison, a bOPV dose evoked corresponding blood ASC responses in 20.0 to 48.6% of subjects. A significant association was found between IgA- and IgG-ASC responses and serum neutralizing antibody titers for poliovirus type 1, 2, 3 (p<0.001). In the IPV group, α4β7+ ASCs accounted for a substantial proportion of IgA-ASCs and the proportion of subjects with a positive α4β7+ IgA-ASC response to poliovirus types 1, 2 and 3 was 62.7%, 89.8% and 45.8%, respectively. A significant association was observed between virus excretion and α4β7+ IgA- and/or IgG-ASC responses to poliovirus type 3 among immunized children; however, only a weak association was found for type 1 poliovirus. Discussion Our results suggest that virus-specific blood ASCs, especially for type 3 poliovirus, can serve as surrogate of mucosal immunity after vaccination. Further studies are needed to evaluate the duration of such memory responses and to assess the programmatic utility of this whole blood-based mucosal ASC testing for the polio eradication program. PMID:26730586
Dey, Ayan; Molodecky, Natalie A; Verma, Harish; Sharma, Prashant; Yang, Jae Seung; Saletti, Giulietta; Ahmad, Mohammad; Bahl, Sunil K; Wierzba, Thomas F; Nandy, Ranjan K; Deshpande, Jagadish M; Sutter, Roland W; Czerkinsky, Cecil
2016-01-01
The "gold standard" for assessing mucosal immunity after vaccination with poliovirus vaccines consists in measuring virus excretion in stool after challenge with oral poliovirus vaccine (OPV). This testing is time and resource intensive, and development of alternative methods is a priority for accelerating polio eradication. We therefore evaluated circulating antibody-secreting cells (ASCs) as a potential means to evaluate mucosal immunity to poliovirus vaccine. 199 subjects, aged 10 years, and previously immunized repeatedly with OPV, were selected. Subjects were assigned to receive either a booster dose of inactivated poliovirus vaccine (IPV), bivalent OPV (bOPV), or no vaccine. Using a micro-modified whole blood-based ELISPOT assay designed for field setting, circulating poliovirus type-specific IgA- and IgG-ASCs, including gut homing α4β7+ ASCs, were enumerated on days 0 and 7 after booster immunization. In addition, serum samples collected on days 0, 28 and 56 were tested for neutralizing antibody titers against poliovirus types 1, 2, and 3. Stool specimens were collected on day 28 (day of bOPV challenge), and on days 31, 35 and 42 and processed for poliovirus isolation. An IPV dose elicited blood IgA- and IgG-ASC responses in 84.8 to 94.9% of subjects, respectively. In comparison, a bOPV dose evoked corresponding blood ASC responses in 20.0 to 48.6% of subjects. A significant association was found between IgA- and IgG-ASC responses and serum neutralizing antibody titers for poliovirus type 1, 2, 3 (p<0.001). In the IPV group, α4β7+ ASCs accounted for a substantial proportion of IgA-ASCs and the proportion of subjects with a positive α4β7+ IgA-ASC response to poliovirus types 1, 2 and 3 was 62.7%, 89.8% and 45.8%, respectively. A significant association was observed between virus excretion and α4β7+ IgA- and/or IgG-ASC responses to poliovirus type 3 among immunized children; however, only a weak association was found for type 1 poliovirus. Our results suggest that virus-specific blood ASCs, especially for type 3 poliovirus, can serve as surrogate of mucosal immunity after vaccination. Further studies are needed to evaluate the duration of such memory responses and to assess the programmatic utility of this whole blood-based mucosal ASC testing for the polio eradication program.
Evaluation of serum lysyl oxidase as a blood test for colorectal cancer.
Ward, S T; Weston, C J; Hepburn, E; Damery, S; Hejmadi, R K; Morton, D G; Middleton, G; Ismail, T; Adams, D H
2014-06-01
Lysyl oxidase (LOX) expression is elevated in colorectal cancer (CRC) tissue and associated with disease progression. A blood test may form a more acceptable diagnostic test for CRC although LOX has not previously been measured in the serum. We therefore sought to determine the clinical usefulness of a serum LOX test for CRC in a symptomatic population. Adult patients referred to a hospital colorectal clinic with bowel symptoms completed a questionnaire and provided a blood sample for serum LOX measurement. Associations between presenting symptoms, serum LOX concentrations and outcomes of investigations were tested by univariate and multivariate analyses to determine if serum LOX was clinically useful in the prediction of CRC. LOX expression in CRC and adjacent colon biopsies was evaluated by ELISA and immunohistochemistry. Thirty-one cases of colorectal cancer and 16 high-risk polyps were identified from a total of 962 participants. There was no association between serum LOX concentration and the presence of CRC, high-risk polyps or cancers at any site. LOX expression was significantly increased in CRC tissue compared to adjacent colon. Despite overexpression of LOX in CRC tissue, elevated serum levels could not be demonstrated. Serum LOX measurement is therefore not a clinically useful test for CRC. Copyright © 2013 Elsevier Ltd. All rights reserved.
Costa, Carla; Brandão, Fátima; Bessa, Maria João; Costa, Solange; Valdiglesias, Vanessa; Kiliç, Gözde; Fernández-Bertólez, Natalia; Quaresma, Pedro; Pereira, Eulália; Pásaro, Eduardo; Laffon, Blanca; Teixeira, João Paulo
2016-03-01
Superparamagnetic iron oxide nanoparticles (ION) have attracted great interest for use in several biomedical fields. In general, they are considered biocompatible, but little is known of their effects on the human nervous system. The main objective of this work was to evaluate the cytotoxicity of two ION (magnetite), coated with silica and oleic acid, previously determining the possible interference of the ION with the methodological procedures to assure the reliability of the results obtained. Human neuroblastoma SHSY5Y and glioblastoma A172 cells were exposed to different concentrations of ION (5-300 µg ml(-1)), prepared in complete and serum-free cell culture medium for three exposure times (3, 6 and 24 h). Cytotoxicity was evaluated by means of the MTT, neutral red uptake and alamar blue assays. Characterization of the main physical-chemical properties of the ION tested was also performed. Results demonstrated that both ION could significantly alter absorbance readings. To reduce these interferences, protocols were modified by introducing additional washing steps and cell-free systems. Significant decreases in cell viability were observed for both cell lines in specific conditions by all assays. In general, oleic acid-coated ION were less cytotoxic than silica-coated ION; besides, a serum-protective effect was observed for both ION studied and cell lines. These results contribute to increase the knowledge of the potential harmful effects of ION on the human nervous system. Understanding these effects is essential to establish satisfactory regulatory policies on the safe use of magnetite nanoparticles in biomedical applications. Copyright © 2015 John Wiley & Sons, Ltd.
Krysiak, Robert; Kowalska, Beata; Szkróbka, Witold; Okopień, Bogusław
2016-02-01
In the light of recent studies, macroprolactinemia seems to occur much more frequently than previously thought. In women, oral contraceptive pills exhibit a stimulatory effect on macroprolactin production. No previous study has investigated macroprolactin levels in androgen-treated hypogonadal men. We studied 10 men with isolated macroprolactinemia and 14 men with normal prolactin levels who because of late-onset hypogonadism were treated with intramuscular testosterone enanthate. Serum prolactin, macroprolactin content, serum testosterone and gonadotropin levels were assessed at baseline and after 4 months of therapy. Although baseline levels of testosterone and gonadotropins were similar in men with and without macroprolactinemia, clinical symptoms were more severe in patients with elevated big-big prolactin levels. As expected, testosterone treatment increased serum testosterone, slightly reduced serum gonadotropins, as well as improved clinical condition in both patients with and without macroprolactinemia, with no difference between the groups. However, testosterone therapy did not affect serum prolactin and macroprolactin content, even after replacing intramuscular testosterone enanthate with oral testosterone undecanoate. Our results suggest a negligible effect of testosterone replacement on macroprolactin levels in macroprolactinemic men with late-onset hypogonadism. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.
Alexandersen, S; Kobinger, G P; Soule, G; Wernery, U
2014-01-01
We tested, using a low starting dilution, sequential serum samples from dromedary camels, sheep and horses collected in Dubai from February/April to October of 2005 and from dromedary camels for export/import testing between Canada and USA in 2000–2001. Using a standard Middle East respiratory syndrome coronavirus (MERS-CoV) neutralization test, serial sera from three sheep and three horses were all negative while sera from 9 of 11 dromedary camels from Dubai were positive for antibodies supported by similar results in a MERS-CoV recombinant partial spike protein antibody ELISA. The two negative Dubai camels were both dromedary calves and remained negative over the 5 months studied. The six dromedary samples from USA and Canada were negative in both tests. These results support the recent findings that infection with MERS-CoV or a closely related virus is not a new occurrence in camels in the Middle East. Therefore, interactions of MERS-CoV at the human–animal interface may have been ongoing for several, perhaps many, years and by inference, a widespread pandemic may be less likely unless significant evolution of the virus allow accelerated infection and spread potential in the human population. PMID:24456414
Testing the Neutral Theory of Biodiversity with Human Microbiome Datasets.
Li, Lianwei; Ma, Zhanshan Sam
2016-08-16
The human microbiome project (HMP) has made it possible to test important ecological theories for arguably the most important ecosystem to human health-the human microbiome. Existing limited number of studies have reported conflicting evidence in the case of the neutral theory; the present study aims to comprehensively test the neutral theory with extensive HMP datasets covering all five major body sites inhabited by the human microbiome. Utilizing 7437 datasets of bacterial community samples, we discovered that only 49 communities (less than 1%) satisfied the neutral theory, and concluded that human microbial communities are not neutral in general. The 49 positive cases, although only a tiny minority, do demonstrate the existence of neutral processes. We realize that the traditional doctrine of microbial biogeography "Everything is everywhere, but the environment selects" first proposed by Baas-Becking resolves the apparent contradiction. The first part of Baas-Becking doctrine states that microbes are not dispersal-limited and therefore are neutral prone, and the second part reiterates that the freely dispersed microbes must endure selection by the environment. Therefore, in most cases, it is the host environment that ultimately shapes the community assembly and tip the human microbiome to niche regime.
Testing the Neutral Theory of Biodiversity with Human Microbiome Datasets
Li, Lianwei; Ma, Zhanshan (Sam)
2016-01-01
The human microbiome project (HMP) has made it possible to test important ecological theories for arguably the most important ecosystem to human health—the human microbiome. Existing limited number of studies have reported conflicting evidence in the case of the neutral theory; the present study aims to comprehensively test the neutral theory with extensive HMP datasets covering all five major body sites inhabited by the human microbiome. Utilizing 7437 datasets of bacterial community samples, we discovered that only 49 communities (less than 1%) satisfied the neutral theory, and concluded that human microbial communities are not neutral in general. The 49 positive cases, although only a tiny minority, do demonstrate the existence of neutral processes. We realize that the traditional doctrine of microbial biogeography “Everything is everywhere, but the environment selects” first proposed by Baas-Becking resolves the apparent contradiction. The first part of Baas-Becking doctrine states that microbes are not dispersal-limited and therefore are neutral prone, and the second part reiterates that the freely dispersed microbes must endure selection by the environment. Therefore, in most cases, it is the host environment that ultimately shapes the community assembly and tip the human microbiome to niche regime. PMID:27527985
Launch Deployment Assembly Extravehicular Activity Neutral Buoyancy Development Test Report
NASA Technical Reports Server (NTRS)
Loughead, T.
1996-01-01
This test evaluated the Launch Deployment Assembly (LDA) design for Extravehicular Activity (EVA) work sites (setup, igress, egress), reach and visual access, and translation required for cargo item removal. As part of the LDA design, this document describes the method and results of the LDA EVA Neutral Buoyancy Development Test to ensure that the LDA hardware support the deployment of the cargo items from the pallet. This document includes the test objectives, flight and mockup hardware description, descriptions of procedures and data collection used in the testing, and the results of the development test at the National Aeronautics and Space Administrations (NASA) Marshall Space Flight Center (MSFC) Neutral Buoyancy Simulator (NBS).
Fully Bayesian tests of neutrality using genealogical summary statistics.
Drummond, Alexei J; Suchard, Marc A
2008-10-31
Many data summary statistics have been developed to detect departures from neutral expectations of evolutionary models. However questions about the neutrality of the evolution of genetic loci within natural populations remain difficult to assess. One critical cause of this difficulty is that most methods for testing neutrality make simplifying assumptions simultaneously about the mutational model and the population size model. Consequentially, rejecting the null hypothesis of neutrality under these methods could result from violations of either or both assumptions, making interpretation troublesome. Here we harness posterior predictive simulation to exploit summary statistics of both the data and model parameters to test the goodness-of-fit of standard models of evolution. We apply the method to test the selective neutrality of molecular evolution in non-recombining gene genealogies and we demonstrate the utility of our method on four real data sets, identifying significant departures of neutrality in human influenza A virus, even after controlling for variation in population size. Importantly, by employing a full model-based Bayesian analysis, our method separates the effects of demography from the effects of selection. The method also allows multiple summary statistics to be used in concert, thus potentially increasing sensitivity. Furthermore, our method remains useful in situations where analytical expectations and variances of summary statistics are not available. This aspect has great potential for the analysis of temporally spaced data, an expanding area previously ignored for limited availability of theory and methods.
Leborgne, Christian; Latournerie, Virginie; Boutin, Sylvie; Desgue, Diana; Quéré, Aliénor; Pignot, Elodie; Collaud, Fanny; Charles, Séverine; Simon Sola, Marcelo; Masat, Elisa; Jouen, Fabienne; Boyer, Olivier; Masurier, Carole; Mingozzi, Federico; Veron, Philippe
2018-03-16
Adeno-associated virus (AAV) vectors are promising candidates for gene therapy and have been explored as gene delivery vehicles in the treatment of Duchenne Muscular Dystrophy (DMD). Recent studies showed compelling evidence of therapeutic efficacy in large animal models following the intravenous delivery of AAV vectors expressing truncated forms of dystrophin. However, to translate these results to humans, careful assessment of the prevalence of anti-AAV neutralizing antibodies (NAbs) is needed, as presence of preexisting NABs to AAV in serum have been associated with a drastic diminution of vector transduction. Here we measured binding and neutralizing antibodies against AAV serotype 1, 2, and 8 in serum from children and young adults with DMD (n = 130). Results were compared with to age-matched healthy donors (HD, n = 113). Overall, approximately 54% of all subjects included in the study presented IgG to AAV2, 49% to AAV1, and 41% to AAV8. A mean of around 80% of IgG positive sera showed neutralizing activity with no statistical difference between DMD and HD. NAb titers for AAV2 were higher than AAV1, and AAV8 in both populations studied. Older DMD patients (13-24 years old) presented significantly lower anti-AAV8 IgG4 subclass. Anti-AAV antibodies were found to be decreased in DMD patients subjected to a 6-month course of corticosteroids and in subjects receiving a variety of immunosuppressive drugs including B cell targeting drugs. Longitudinal follow up of humoral responses to AAV over up to 6 years showed no change in antibody titers, suggesting that in this patient population, seroconversion is a rare event in humans. Copyright © 2018. Published by Elsevier Inc.
Kiefer, Jonathan D.; Srinivas, Raja R.; Lobner, Elisabeth; Tisdale, Alison W.; Mehta, Naveen K.; Yang, Nicole J.; Tidor, Bruce; Wittrup, K. Dane
2016-01-01
The Sso7d protein from the hyperthermophilic archaeon Sulfolobus solfataricus is an attractive binding scaffold because of its small size (7 kDa), high thermal stability (Tm of 98 °C), and absence of cysteines and glycosylation sites. However, as a DNA-binding protein, Sso7d is highly positively charged, introducing a strong specificity constraint for binding epitopes and leading to nonspecific interaction with mammalian cell membranes. In the present study, we report charge-neutralized variants of Sso7d that maintain high thermal stability. Yeast-displayed libraries that were based on this reduced charge Sso7d (rcSso7d) scaffold yielded binders with low nanomolar affinities against mouse serum albumin and several epitopes on human epidermal growth factor receptor. Importantly, starting from a charge-neutralized scaffold facilitated evolutionary adaptation of binders to differentially charged epitopes on mouse serum albumin and human epidermal growth factor receptor, respectively. Interestingly, the distribution of amino acids in the small and rigid binding surface of enriched rcSso7d-based binders is very different from that generally found in more flexible antibody complementarity-determining region loops but resembles the composition of antibody-binding energetic hot spots. Particularly striking was a strong enrichment of the aromatic residues Trp, Tyr, and Phe in rcSso7d-based binders. This suggests that the rigidity and small size of this scaffold determines the unusual amino acid composition of its binding sites, mimicking the energetic core of antibody paratopes. Despite the high frequency of aromatic residues, these rcSso7d-based binders are highly expressed, thermostable, and monomeric, suggesting that the hyperstability of the starting scaffold and the rigidness of the binding surface confer a high tolerance to mutation. PMID:27582495
Halbert, Christine L.; Miller, A. Dusty; McNamara, Sharon; Emerson, Julia; Gibson, Ronald L.; Ramsey, Bonnie; Aitken, Moira L.
2014-01-01
Adeno-associated virus (AAV) vectors are promising candidates for gene therapy directed to the lungs, in particular for treatment of cystic fibrosis (CF). In animal models of lung gene transfer, neutralizing antibodies in serum made in response to vector exposure have been associated with a partial to complete block to repeat transduction by vectors with the same capsid type, thus transduction by AAV vectors might be inefficient in humans previously exposed to the same AAV type. AAV type 2 (AAV2) has been used in clinical trials of lung gene transfer, but AAV5 and AAV6 have been shown to mediate more efficient transduction in rodent lungs and in cultured human airway epithelia compared to that of AAV2. Here we have measured neutralizing antibodies against AAV type 2, 5, and 6 vectors in serum from children and adults with CF, and from normal adults. About 30% of adults were seropositive for AAV2, 20–30% were seropositive for AAV6, and 10–20% were seropositive for AAV5. CF children were seropositive for AAV types 2, 5, or 6 at rates of 4–15%. All individuals seropositive for AAV6 were also seropositive for AAV2, and the AAV6 titer was low compared to the AAV2 titer. AAV5-positive sera were lower both in titers and rates than those seen for AAV6. The results indicate that AAV type 2, 5 or 6 exposure is low in CF and control populations and even lower in CF children. PMID:16610931
Lee, E-Chiang; Desai, Urvi; Gololobov, Gennady; Hong, Seokjoo; Feng, Xiao; Yu, Xuan-Chuan; Gay, Jason; Wilganowski, Nat; Gao, Cuihua; Du, Ling-Ling; Chen, Joan; Hu, Yi; Zhao, Sharon; Kirkpatrick, Laura; Schneider, Matthias; Zambrowicz, Brian P.; Landes, Greg; Powell, David R.; Sonnenburg, William K.
2009-01-01
Angiopoietin-like 3 (ANGPTL3) and angiopoietin-like 4 (ANGPTL4) are secreted proteins that regulate triglyceride (TG) metabolism in part by inhibiting lipoprotein lipase (LPL). Recently, we showed that treatment of wild-type mice with monoclonal antibody (mAb) 14D12, specific for ANGPTL4, recapitulated the Angptl4 knock-out (-/-) mouse phenotype of reduced serum TG levels. In the present study, we mapped the region of mouse ANGPTL4 recognized by mAb 14D12 to amino acids Gln29–His53, which we designate as specific epitope 1 (SE1). The 14D12 mAb prevented binding of ANGPTL4 with LPL, consistent with its ability to neutralize the LPL-inhibitory activity of ANGPTL4. Alignment of all angiopoietin family members revealed that a sequence similar to ANGPTL4 SE1 was present only in ANGPTL3, corresponding to amino acids Glu32–His55. We produced a mouse mAb against this SE1-like region in ANGPTL3. This mAb, designated 5.50.3, inhibited the binding of ANGPTL3 to LPL and neutralized ANGPTL3-mediated inhibition of LPL activity in vitro. Treatment of wild-type as well as hyperlipidemic mice with mAb 5.50.3 resulted in reduced serum TG levels, recapitulating the lipid phenotype found in Angptl3-/- mice. These results show that the SE1 region of ANGPTL3 and ANGPTL4 functions as a domain important for binding LPL and inhibiting its activity in vitro and in vivo. Moreover, these results demonstrate that therapeutic antibodies that neutralize ANGPTL4 and ANGPTL3 may be useful for treatment of some forms of hyperlipidemia. PMID:19318355
NASA Astrophysics Data System (ADS)
de Angelis, E.; di Lellis, A. M.; Orsini, S.; Zanza, V.; Maggi, M.; Vertolli, N.; D'Amicis, R.; Tilia, B.; Sibio, A.
2003-04-01
An Energetic Neutral Atoms facility to test and calibrate Neutral Atoms Analyzers has been developed in the Scientific Technical Unit of Fusion at the ENEA Research Center in Frascati (Rome-Italy). In the last years a collaboration with IFSI (Interplanetary Space and Physics Institute, CNR-Rome-Italy) has allowed to use this facility for space sensors and for characterization of crucial instruments elements. The ENA beam is realized with an ion source and a neutralization cell, and allows to test any instrument in the energy range 300eV-110keV with the available masses of Hydrogen, Deuterium or Helium. At the moment, the critical elements of ELENA (Emitted Low Energy Neutral Atoms) instrument proposed for BepiColombo ESA cornerstone mission to Mercury is under development testing. The facility, its potentiality and the instrument characterization progresses are presented.
Frisk, A. L.; König, M.; Moritz, A.; Baumgärtner, W.
1999-01-01
Reverse transcription-PCR (RT-PCR) was used to detect canine distemper virus (CDV) nucleoprotein (NP) RNA in serum, whole blood, and cerebrospinal fluid (CSF) samples from 38 dogs with clinically suspected distemper. Results were correlated to clinical findings, anti-CDV neutralizing antibody titers, postmortem findings, and demonstration of CDV NP antigen by immunohistochemistry. The specificity of the RT-PCR was ensured by amplification of RNA from various laboratory CDV strains, restriction enzyme digestion, and Southern blot hybridization. In 29 of 38 dogs, CDV infection was confirmed by postmortem examination and immunohistochemistry. The animals displayed the catarrhal, systemic, and nervous forms of distemper. Seventeen samples (serum, whole blood, or CSF) from dogs with distemper were tested with three sets of primers targeted to different regions of the NP gene of the CDV Onderstepoort strain. Expected amplicons were observed in 82, 53, and 41% of the 17 samples, depending upon the primer pair used. With the most sensitive primer pair (primer pair I), CDV NP RNA was detected in 25 of 29 (86%) serum samples and 14 of 16 (88%) whole blood and CSF samples from dogs with distemper but not in body fluids from immunohistochemically negative dogs. Nucleotide sequence analysis of five RT-PCR amplicons from isolates from the field revealed few silent point mutations. These isolates exhibited greater homology to the Rockborn (97 to 99%) than to the Onderstepoort (95 to 96%) CDV strain. In summary, although the sensitivity of the RT-PCR for detection of CDV is strongly influenced by the location of the selected primers, this nucleic acid detection system represents a highly specific and sensitive method for the antemortem diagnosis of distemper in dogs, regardless of the form of distemper, humoral immune response, and viral antigen distribution. PMID:10523566
Widjaja, Ivy; Ahout, Inge M. L.; de Groot, Ronald; Guichelaar, Teun; Luytjes, Willem; de Jonge, Marien I.; de Haan, Cornelis A. M.; Ferwerda, Gerben
2017-01-01
Respiratory syncytial virus (RSV) is the leading cause for respiratory illness that requires hospitalization in infancy. High levels of maternal antibodies can protect against RSV infection. However, RSV-infected infants can suffer from severe disease symptoms even in the presence of high levels of RSV-specific antibodies. This study analyzes several serological characteristics to explore potential deficiencies or surpluses of antibodies that could relate to severe disease symptoms. We compare serum antibodies from hospitalized patients who suffered severe symptoms as well as uninfected infants. Disease severity markers were oxygen therapy, tachypnea, oxygen saturation, admission to the intensive care unit and duration of hospitalization. Antibodies against RSV G protein and a prefusion F epitope correlated with in vitro neutralization. Avidity of RSV-specific IgG antibodies was lower in RSV-infected infants compared to uninfected controls. Severe disease symptoms were unrelated to RSV-specific IgG antibody titers, avidity of RSV-IgG, virus neutralization capacity or titers against pre- and postfusion F or G protein ectodomains and the prefusion F antigenic site Ø. In conclusion, the detailed serological characterization did not indicate dysfunctional or epitope-skewed composition of serum antibodies in hospitalized RSV-infected infants suffering from severe disease symptoms. It remains unclear, whether specific antibody fractions could diminish disease symptoms. PMID:28135305
Jans, Jop; Wicht, Oliver; Widjaja, Ivy; Ahout, Inge M L; de Groot, Ronald; Guichelaar, Teun; Luytjes, Willem; de Jonge, Marien I; de Haan, Cornelis A M; Ferwerda, Gerben
2017-01-01
Respiratory syncytial virus (RSV) is the leading cause for respiratory illness that requires hospitalization in infancy. High levels of maternal antibodies can protect against RSV infection. However, RSV-infected infants can suffer from severe disease symptoms even in the presence of high levels of RSV-specific antibodies. This study analyzes several serological characteristics to explore potential deficiencies or surpluses of antibodies that could relate to severe disease symptoms. We compare serum antibodies from hospitalized patients who suffered severe symptoms as well as uninfected infants. Disease severity markers were oxygen therapy, tachypnea, oxygen saturation, admission to the intensive care unit and duration of hospitalization. Antibodies against RSV G protein and a prefusion F epitope correlated with in vitro neutralization. Avidity of RSV-specific IgG antibodies was lower in RSV-infected infants compared to uninfected controls. Severe disease symptoms were unrelated to RSV-specific IgG antibody titers, avidity of RSV-IgG, virus neutralization capacity or titers against pre- and postfusion F or G protein ectodomains and the prefusion F antigenic site Ø. In conclusion, the detailed serological characterization did not indicate dysfunctional or epitope-skewed composition of serum antibodies in hospitalized RSV-infected infants suffering from severe disease symptoms. It remains unclear, whether specific antibody fractions could diminish disease symptoms.
Wui, Seo Ri; Han, Ji Eun; Kim, Yeon Hee; Rhie, Gi-eun; Lee, Na Gyong
2013-04-01
Anthrax is an acute infectious disease caused by Bacillus anthracis. We previously reported that the adjuvant CIA06B, which consists of TLR4 agonist CIA05 and aluminum hydroxide (alum), enhanced the immune response to anthrax protective antigen (PA) in mice. This study was carried out to determine whether CIA06B can enhance long-term immune responses to PA in mice. BALB/c mice were immunized intramuscularly three times at 2-week intervals with recombinant PA alone or PA combined with alum or CIA06B. At 8 and 24 weeks post-immunization, the immunological responses including serum anti-PA IgG antibody titer, toxin-neutralizing antibody titer, splenic cytokine secretion and the frequency of PA-specific memory B cells were assessed. Compared with mice injected with PA alone or PA plus alum, mice injected with PA plus CIA06B had higher titers of serum anti-PA IgG antibodies, and higher frequencies of PA-specific memory B cells and interferon-γ secreting cells. Furthermore, anti-PA antibodies induced by CIA06B were more effective in neutralizing anthrax toxin. These results demonstrated that CIA06B is capable of providing long-term immunity when used as an adjuvant in a PA-based anthrax vaccine.
The yerba mate intake has a neutral effect on bone: A case-control study in postmenopausal women.
da Veiga, Denise T A; Bringhenti, Raísa; Bolignon, Aline A; Tatsh, Etiane; Moresco, Rafael N; Comim, Fabio V; Premaor, Melissa O
2018-01-01
Nutritional factors have been associated with osteoporosis and fractures. The intake of coffee may increase the risk of fracture whereas the intake of black and green tea is associated with its reduction. Recently, consumption of yerba mate was associated with increased bone mineral density in postmenopausal women. Nonetheless, its influence on fracture is not known. The aim of this study was to evaluate the effect of yerba mate tea intake on fractures, bone markers, calcium homeostasis, and oxidative stress in postmenopausal women. A case-control study was carried out in South Brazil, 46 women with fractures and 49 controls completed the study. There was no significant difference between the frequency of fractures in women who drank mate tea and women who did not (48.3% vs. 48.5%, p = .99). Moreover, there was no significant difference concerning the serum levels of total calcium, phosphorus, PTH, vitamin D, P1NP, and CTX in the subjects with the history of yerba mate use when compared to controls. Higher serum levels of NOx were found in women who drank the yerba mate infusion. In conclusion, the yerba mate intake is not associated with fracture, and it appears to have a neutral effect on the bone metabolism. Copyright © 2017 John Wiley & Sons, Ltd.
Pearce, R.D.; O'Shea, T.J.; Shankar, V.; Rupprecht, C.E.
2007-01-01
Recently, bat ectoparasites have been demonstrated to harbor pathogens of potential importance to humans. We evaluated antirabies antibody seroprevalence and the presence of ectoparasites in big brown bats (Eptesicus fuscus) sampled in 2002 and 2003 in Colorado to investigate if an association existed between ectoparasite intensity and exposure to rabies virus (RV). We used logistic regression and Akaike's Information Criteria adjusted for sample size (AICc) in a post-hoc analysis to investigate the relative importance of three ectoparasite species, as well as bat colony size, year sampled, age class, colony size, and year interaction on the presence of rabies virus neutralizing antibodies (VNA) in serum of wild E. fuscus. We obtained serum samples and ectoparasite counts from big brown bats simultaneously in 2002 and 2003. Although the presence of ectoparasites (Steatonyssus occidentalis and Spinturnix bakeri) were important in elucidating VNA seroprevalence, their intensities were higher in seronegative bats than in seropositive bats, and the presence of a third ectoparasite (Cimex pilosellus) was inconsequential. Colony size and year sampled were the most important variables in these AICc models. These findings suggest that these ectoparasites do not enhance exposure of big brown bats to RV. ?? 2007 Mary Ann Liebert, Inc.
Weinberg, Adriana; Song, Lin-Ye; Walker, Robert; Allende, Maria; Fenton, Terence; Patterson-Bartlett, Julie; Nachman, Sharon; Kemble, George; Yi, Ting-Ting; Defechereux, Patricia; Wara, Diane; Read, Jennifer S; Levin, Myron
2010-10-01
Live-attenuated influenza vaccine (LAIV) prevents more cases of influenza in immune-competent children than the trivalent inactivated vaccine (TIV). We compared the antibody responses to LAIV or TIV in HIV-infected children. Blood and saliva obtained at enrollment, 4 and 24 weeks postimmunization from 243 HIV-infected children randomly assigned to TIV or LAIV were analyzed. Both vaccines increased the anti-influenza neutralizing antibodies at 4 and 24 weeks postimmunization. At 4 weeks postimmunization, TIV recipients had 2-fold to 3-fold higher neutralizing antibody titers than LAIV recipients, but the proportions of subjects with protective titers (≥ 1:40) were similar between treatment groups (96%-100% for influenza A and 81%-88% for influenza B). Both vaccines increased salivary homotypic IgG antibodies, but not IgA antibodies. Both vaccines also increased serum heterosubtypic antibodies. Among HIV-specific characteristics, the baseline viral load correlated best with the antibody responses to either vaccine. We used LAIV-virus shedding as a surrogate of influenza infection. Influenza-specific humoral and mucosal antibody levels were significantly higher in nonshedders than in shedders. LAIV and TIV generated homotypic and heterosubtypic humoral and mucosal antibody responses in HIV-infected children. High titers of humoral or mucosal antibodies correlated with protection against viral shedding.
Studies of guinea pig immunoglobulin isotype, idiotype and antiidiotype
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tirrell, S.M.
1988-01-01
Immunization of Guinea pigs with diphtheria toxoid generated antibodies of the IgG class that were capable of neutralizing native toxin in vivo. Sera from these animals were used to affinity purify idiotypic antibodies (AB1). AB1 vaccines derived from the IgG1 class and from F(ab{prime}){sub 2} of IgG1 + IgG2 (IgG1/2) classes were effective in inducing a syngeneic anti-idiotype (AB2) response. Animals immunized with AB1 consisting of both IgG1/2 did not elicit a detectable AB2 response. Binding of homologous {sup 125}I-F(ab{prime}){sub 2} (AB1) to the antiidiotype was inhibited 90% in the presence of DT.F(ab{prime}){sub 2} derived from preimmune serum or hadmore » no inhibitory effects on the idiotype-antiidiotype interactions. Two groups of outbred guinea pigs were vaccinated with alum absorbed F(ab{prime}){sub 2} of anti-idiotype IgG1/2 (AB2). Of the ten animals inoculated with AB2, three tested positive by RIA against {sup 125}I-DT. Two of the RIA positive sera contained antibodies that neutralized diphtheria toxin in a rabbit intracutaneous assay. Purification of guinea pig IgG by protein A-Sepharose affinity chromatography resulted in the separation of three distinct IgG populations.« less