Referencing cross-reactivity of detection antibodies for protein array experiments [version 1; referees: 1 approved, 2 approved with reservations

Directory of Open Access Journals (Sweden)

Darragh Lemass

2016-01-01

Full Text Available Protein arrays are frequently used to profile antibody repertoires in humans and animals. High-throughput protein array characterisation of complex antibody repertoires requires a platform-dependent, lot-to-lot validation of secondary detection antibodies. This article details the validation of an affinity-isolated anti-chicken IgY antibody produced in rabbit and a goat anti-rabbit IgG antibody conjugated with alkaline phosphatase using protein arrays consisting of 7,390 distinct human proteins. Probing protein arrays with secondary antibodies in absence of chicken serum revealed non-specific binding to 61 distinct human proteins. The cross-reactivity of the tested secondary detection antibodies points towards the necessity of platform-specific antibody characterisation studies for all secondary immunoreagents. Secondary antibody characterisation using protein arrays enables generation of reference lists of cross-reactive proteins, which can be then excluded from analysis in follow-up experiments. Furthermore, making such cross-reactivity lists accessible to the wider research community may help to interpret data generated by the same antibodies in applications not related to protein arrays such as immunoprecipitation, Western blots or other immunoassays.

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

DEFF Research Database (Denmark)

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

1996-01-01

Synthetic P. falciparum peptides were evaluated as tools in epidemiological investigations of malaria. Plasma IgM and IgG antibody reactivities against synthetic peptides covering sequences of glutamate-rich protein (GLURP) and acidic-basic repeat antigen (ABRA) were measured by ELISA...... in individuals from malaria-endemic areas of Sudan, Indonesia and The Gambia to study antibody responses to these peptides in donors living in areas of different malaria endemicity. IgG and IgM reactivities to the peptides increased with malaria endemicity, although there were no differences in reactivities...... tested were shortlived in most patients. In Gambian children with malaria, IgM reactivities but not IgG antibody reactivities against the ABRA peptide were higher in those with mild malaria than in those with severe malaria. The peptides may be useful in future epidemiological studies, especially...

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

Directory of Open Access Journals (Sweden)

M Anthony Moody

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

Seasonal influenza vaccination is the strongest correlate of cross-reactive antibody responses in migratory bird handlers.

Science.gov (United States)

Oshansky, Christine M; Wong, Sook-San; Jeevan, Trushar; Smallwood, Heather S; Webby, Richard J; Shafir, Shira C; Thomas, Paul G

2014-12-09

Avian species are reservoirs of influenza A viruses and could harbor viruses with significant pandemic potential. We examined the antibody and cellular immune responses to influenza A viruses in field or laboratory workers with a spectrum of occupational exposure to avian species for evidence of zoonotic infections. We measured the seroprevalence and T cell responses among 95 individuals with various types and degrees of prior field or laboratory occupational exposure to wild North American avian species using whole blood samples collected in 2010. Plasma samples were tested using endpoint enzyme-linked immunosorbent assay (ELISA) and hemagglutination (HA) inhibition (HAI) assays to subtypes H3, H4, H5, H6, H7, H8, and H12 proteins. Detectable antibodies were found against influenza HA antigens in 77% of individuals, while 65% of individuals tested had measurable T cell responses (gamma interferon [IFN-γ] enzyme-linked immunosorbent spot assay [ELISPOT]) to multiple HA antigens of avian origin. To begin defining the observed antibody specificities, Spearman rank correlation analysis showed that ELISA responses, which measure both head- and stalk-binding antibodies, do not predict HAI reactivities, which measure primarily head-binding antibodies. This result suggests that ELISA titers can report cross-reactivity based on the levels of non-head-binding responses. However, the strongest positive correlate of HA-specific ELISA antibody titers was receipt of seasonal influenza virus vaccination. Occupational exposure was largely uncorrelated with serological measures, with the exception of individuals exposed to poultry, who had higher levels of H7-specific antibodies than non-poultry-exposed individuals. While the cohort had antibody and T cell reactivity to a broad range of influenza viruses, only occupational exposure to poultry was associated with a significant difference in antibody levels to a specific subtype (H7). There was no evidence that T cell assays

PET CT Identifies Reactivation Risk in Cynomolgus Macaques with Latent M. tuberculosis.

Directory of Open Access Journals (Sweden)

Philana Ling Lin

2016-07-01

Full Text Available Mycobacterium tuberculosis infection presents across a spectrum in humans, from latent infection to active tuberculosis. Among those with latent tuberculosis, it is now recognized that there is also a spectrum of infection and this likely contributes to the variable risk of reactivation tuberculosis. Here, functional imaging with 18F-fluorodeoxygluose positron emission tomography and computed tomography (PET CT of cynomolgus macaques with latent M. tuberculosis infection was used to characterize the features of reactivation after tumor necrosis factor (TNF neutralization and determine which imaging characteristics before TNF neutralization distinguish reactivation risk. PET CT was performed on latently infected macaques (n = 26 before and during the course of TNF neutralization and a separate set of latently infected controls (n = 25. Reactivation occurred in 50% of the latently infected animals receiving TNF neutralizing antibody defined as development of at least one new granuloma in adjacent or distant locations including extrapulmonary sites. Increased lung inflammation measured by PET and the presence of extrapulmonary involvement before TNF neutralization predicted reactivation with 92% sensitivity and specificity. To define the biologic features associated with risk of reactivation, we used these PET CT parameters to identify latently infected animals at high risk for reactivation. High risk animals had higher cumulative lung bacterial burden and higher maximum lesional bacterial burdens, and more T cells producing IL-2, IL-10 and IL-17 in lung granulomas as compared to low risk macaques. In total, these data support that risk of reactivation is associated with lung inflammation and higher bacterial burden in macaques with latent Mtb infection.

Soluble HIV-1 envelope immunogens derived from an elite neutralizer elicit cross-reactive V1V2 antibodies and low potency neutralizing antibodies.

Directory of Open Access Journals (Sweden)

Sara Carbonetti

Full Text Available We evaluated four gp140 Envelope protein vaccine immunogens that were derived from an elite neutralizer, subject VC10042, whose plasma was able to potently neutralize a wide array of genetically distinct HIV-1 isolates. We sought to determine whether soluble Envelope proteins derived from the viruses circulating in VC10042 could be used as immunogens to elicit similar neutralizing antibody responses by vaccination. Each gp140 was tested in its trimeric and monomeric forms, and we evaluated two gp140 trimer vaccine regimens in which adjuvant was supplied at all four immunizations or at only the first two immunizations. Interestingly, all four Envelope immunogens elicited high titers of cross-reactive antibodies that recognize the variable regions V1V2 and are potentially similar to antibodies linked with a reduced risk of HIV-1 acquisition in the RV144 vaccine trial. Two of the four immunogens elicited neutralizing antibody responses that neutralized a wide array of HIV-1 isolates from across genetic clades, but those responses were of very low potency. There were no significant differences in the responses elicited by trimers or monomers, nor was there a significant difference between the two adjuvant regimens. Our study identified two promising Envelope immunogens that elicited anti-V1V2 antibodies and broad, but low potency, neutralizing antibody responses.

Clinical relevance of anti-exenatide antibodies: safety, efficacy and cross-reactivity with long-term treatment

NARCIS (Netherlands)

Fineman, M.S.; Mace, K.F.; Diamant, M.; Darsow, T.; Cirincione, B.B.; Porter, T.K.B.; Kinninger, L.A.; Trautmann, M.E.

2012-01-01

Aims: Antibody formation to therapeutic peptides is common. This analysis characterizes the time-course and cross-reactivity of anti-exenatide antibodies and potential effects on efficacy and safety. Methods: Data from intent-to-treat patients in 12 controlled (n = 2225,12-52weeks) and 5

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

Directory of Open Access Journals (Sweden)

Siddhi P Shah

2016-01-01

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

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

Science.gov (United States)

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

2013-07-01

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

Maturation Pathways of Cross-Reactive HIV-1 Neutralizing Antibodies

Directory of Open Access Journals (Sweden)

Dimiter S. Dimitrov

2009-11-01

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

Antibodies to actin in autoimmune haemolytic anaemia

Directory of Open Access Journals (Sweden)

Ritzmann Mathias

2010-03-01

Full Text Available Abstract Background In autoimmune haemolytic anaemia (AIHA, autoreactive antibodies directed against red blood cells are up-regulated, leading to erythrocyte death. Mycoplasma suis infections in pigs induce AIHA of both the warm and cold types. The aim of this study was to identify the target autoantigens of warm autoreactive IgG antibodies. Sera from experimentally M. suis-infected pigs were screened for autoreactivity. Results Actin-reactive antibodies were found in the sera of 95% of all animals tested. The reactivity was species-specific, i.e. reactivity with porcine actin was significantly higher than with rabbit actin. Sera of animals previously immunised with the M. suis adhesion protein MSG1 showed reactivity with actin prior to infection with M. suis indicating that molecular mimicry is involved in the specific autoreactive mechanism. A potentially cross-reactive epitope was detected. Conclusions This is the first report of autoreactive anti-actin antibodies involved in the pathogenesis of autoimmune haemolytic anaemia.

Schistosome infection intensity is inversely related to auto-reactive antibody levels.

Directory of Open Access Journals (Sweden)

Francisca Mutapi

2011-05-01

Full Text Available In animal experimental models, parasitic helminth infections can protect the host from auto-immune diseases. We conducted a population-scale human study investigating the relationship between helminth parasitism and auto-reactive antibodies and the subsequent effect of anti-helminthic treatment on this relationship. Levels of antinuclear antibodies (ANA and plasma IL-10 were measured by enzyme linked immunosorbent assay in 613 Zimbabweans (aged 2-86 years naturally exposed to the blood fluke Schistosoma haematobium. ANA levels were related to schistosome infection intensity and systemic IL-10 levels. All participants were offered treatment with the anti-helminthic drug praziquantel and 102 treated schoolchildren (5-16 years were followed up 6 months post-antihelminthic treatment. ANA levels were inversely associated with current infection intensity but were independent of host age, sex and HIV status. Furthermore, after allowing for the confounding effects of schistosome infection intensity, ANA levels were inversely associated with systemic levels of IL-10. ANA levels increased significantly 6 months after anti-helminthic treatment. Our study shows that ANA levels are attenuated in helminth-infected humans and that anti-helminthic treatment of helminth-infected people can significantly increase ANA levels. The implications of these findings are relevant for understanding both the aetiology of immune disorders mediated by auto-reactive antibodies and in predicting the long-term consequences of large-scale schistosomiasis control programs.

Hybridization-based antibody cDNA recovery for the production of recombinant antibodies identified by repertoire sequencing.

Science.gov (United States)

Valdés-Alemán, Javier; Téllez-Sosa, Juan; Ovilla-Muñoz, Marbella; Godoy-Lozano, Elizabeth; Velázquez-Ramírez, Daniel; Valdovinos-Torres, Humberto; Gómez-Barreto, Rosa E; Martinez-Barnetche, Jesús

2014-01-01

High-throughput sequencing of the antibody repertoire is enabling a thorough analysis of B cell diversity and clonal selection, which may improve the novel antibody discovery process. Theoretically, an adequate bioinformatic analysis could allow identification of candidate antigen-specific antibodies, requiring their recombinant production for experimental validation of their specificity. Gene synthesis is commonly used for the generation of recombinant antibodies identified in silico. Novel strategies that bypass gene synthesis could offer more accessible antibody identification and validation alternatives. We developed a hybridization-based recovery strategy that targets the complementarity-determining region 3 (CDRH3) for the enrichment of cDNA of candidate antigen-specific antibody sequences. Ten clonal groups of interest were identified through bioinformatic analysis of the heavy chain antibody repertoire of mice immunized with hen egg white lysozyme (HEL). cDNA from eight of the targeted clonal groups was recovered efficiently, leading to the generation of recombinant antibodies. One representative heavy chain sequence from each clonal group recovered was paired with previously reported anti-HEL light chains to generate full antibodies, later tested for HEL-binding capacity. The recovery process proposed represents a simple and scalable molecular strategy that could enhance antibody identification and specificity assessment, enabling a more cost-efficient generation of recombinant antibodies.

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

Directory of Open Access Journals (Sweden)

Mei-Liang Huang

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

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

Directory of Open Access Journals (Sweden)

SuhandanAdigüzel Van-Zoelen

2015-10-01

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

High-resolution mapping of linear antibody epitopes using ultrahigh-density peptide microarrays

DEFF Research Database (Denmark)

Buus, Søren; Rockberg, Johan; Forsström, Björn

2012-01-01

Antibodies empower numerous important scientific, clinical, diagnostic, and industrial applications. Ideally, the epitope(s) targeted by an antibody should be identified and characterized, thereby establishing antibody reactivity, highlighting possible cross-reactivities, and perhaps even warning...... against unwanted (e.g. autoimmune) reactivities. Antibodies target proteins as either conformational or linear epitopes. The latter are typically probed with peptides, but the cost of peptide screening programs tends to prohibit comprehensive specificity analysis. To perform high-throughput, high......-resolution mapping of linear antibody epitopes, we have used ultrahigh-density peptide microarrays generating several hundred thousand different peptides per array. Using exhaustive length and substitution analysis, we have successfully examined the specificity of a panel of polyclonal antibodies raised against...

Primary biliary cirrhosis is characterized by IgG3 antibodies cross-reactive with the major mitochondrial autoepitope and its Lactobacillus mimic.

Science.gov (United States)

Bogdanos, Dimitrios-Petrou; Baum, Harold; Okamoto, Manabu; Montalto, Paolo; Sharma, Umesh C; Rigopoulou, Eirini I; Vlachogiannakos, John; Ma, Yun; Burroughs, Andrew K; Vergani, Diego

2005-08-01

The serological hallmark of primary biliary cirrhosis (PBC) is the presence of pyruvate dehydrogenase complex E2 subunit (PDC-E2) antimitochondrial antibodies (AMAs). Anti-PDC-E2 antibodies cross-react specifically with mycobacterial hsp65, and we have demonstrated that the motif SxGDL[ILV]AE shared by PDC-E2(212-226) and hsp's is a cross-reactive target. Having found that this same motif is present only in beta-galactosidase of Lactobacillus delbrueckii (BGAL LACDE), we hypothesized that this homology would also lead to cross-reactivity. The mimics were tested via ELISA for reactivity and competitive cross-reactivity using sera from 100 AMA-positive and 23 AMA-negative PBC patients and 190 controls. An Escherichia coli (ECOLI) PDC-E2 mimic that has been pathogenetically linked to PBC but lacks this motif has been also tested. Anti-BGAL(266-280) LACDE antibodies were restricted to AMA-positive patients (54 of 95, 57%) and belonged to immunoglobulin (Ig) G3. Of the 190 controls, 22 (12%; P ECOLI PDC-E2 reactivity was virtually absent. BGAL(266-280)/PDC-E2(212-226) reactivity of the IgG3 isotype was found in 52 (52%) AMA-positive PBC patients but in only 1 of the controls (P ECOLI PDC-E2 mimics. In conclusion, IgG3 antibodies to BGAL LACDE cross-react with the major mitochondrial autoepitope and are characteristic of PBC.

Passive immunization against Cryptococcus neoformans with an isotype-switch family of monoclonal antibodies reactive with cryptococcal polysaccharide.

OpenAIRE

Sanford, J E; Lupan, D M; Schlageter, A M; Kozel, T R

1990-01-01

The in vivo properties of an immunoglobulin isotype-switch family of monoclonal antibodies specific for the polysaccharide capsule of Cryptococcus neoformans were examined in a murine model of cryptococcosis. Subclass-switch variants were isolated by sequential sublining of an immunoglobulin G subclass 1 (IgG1)-secreting cell line. Antibodies of the IgG1, IgG2a, and IgG2b isotypes with identical reactivities with cryptococcal polysaccharide were prepared. The antibodies had the distinct biolo...

Anti-carbamylated Protein Antibody Levels Correlate with Anti-Sa (Citrullinated Vimentin) Antibody Levels in Rheumatoid Arthritis.

Science.gov (United States)

Challener, Gregory J; Jones, Jonathan D; Pelzek, Adam J; Hamilton, B JoNell; Boire, Gilles; de Brum-Fernandes, Artur José; Masetto, Ariel; Carrier, Nathalie; Ménard, Henri A; Silverman, Gregg J; Rigby, William F C

2016-02-01

The presence of anticitrullinated protein antibodies (ACPA) in rheumatoid arthritis (RA) indicates a breach in immune tolerance. Recent studies indicate that this breach extends to homocitrullination of lysines with the formation of anti-carbamylated protein (anti-CarP) antibodies. We analyzed the clinical and serologic relationships of anti-CarP in 2 RA cohorts. Circulating levels of immunoglobulin G anti-CarP antibodies were determined by ELISA in established (Dartmouth-Hitchcock Medical Center) and early (Sherbrooke University Hospital Center) cohorts and evaluated for anticyclic citrullinated peptide antibodies (anti-CCP), specific ACPA, and rheumatoid factor (RF) levels using the Student t test and correlation analysis. We identified elevated anti-CarP antibodies titers in 47.0% of seropositive patients (Dartmouth, n = 164), with relationships to anti-CCP (p < 0.0001) and IgM-RF (p = 0.001). Similarly, 38.2% of seropositive patients from the Sherbrooke cohort (n = 171) had elevated anti-CarP antibodies; titers correlated to anti-CCP (p = 0.01) but not IgM-RF (p = 0.09). A strong correlation with anti-Sa was observed: 47.9% anti-Sa+ patients were anti-CarP antibodies+ versus only 25.4% anti-Sa- in the Sherbrooke cohort (p = 0.0002), and 62.6% anti-Sa+ patients versus 26.9% anti-Sa- were anti-CarP antibodies+ in Dartmouth (p < 0.0001). We found a more variable response for reactivity to citrullinated fibrinogen or to citrullinated peptides from fibrinogen and α enolase. In 2 North American RA cohorts, we observed a high prevalence of anti-CarP antibody positivity. We also describe a surprising and unexpected association of anti-CarP with anti-Sa antibodies that could not be explained by cross-reactivity. Further, considerable heterogeneity exists between anti-CarP reactivity and other citrullinated peptide reactivity, raising the question of how the pathogenesis of antibody responses for carbamylated proteins and citrullinated proteins may be linked in vivo.

Potential for novel MUC1 glycopeptide-specific antibody in passive cancer immunotherapy

DEFF Research Database (Denmark)

Madsen, Caroline B; Wandall, Hans H; Pedersen, Anders Elm

2013-01-01

MUC1 is an important target for antibodies in passive cancer immunotherapy. Antibodies against mucin glycans or mucin peptide backbone alone may give rise to cross reactivity with normal tissues. Therefore, attempts to identify antibodies against cancer-specific MUC1 glycopeptide epitopes havebeen...

Naturally occurring anti-glycan antibodies binding to Globo H-expressing cells identify ovarian cancer patients.

Science.gov (United States)

Pochechueva, Tatiana; Alam, Shahidul; Schötzau, Andreas; Chinarev, Alexander; Bovin, Nicolai V; Hacker, Neville F; Jacob, Francis; Heinzelmann-Schwarz, Viola

2017-02-10

Glycosphingolipids are important compounds of the plasma membrane of mammalian cells and a number of them have been associated with malignant transformation and progression, reinforcing tumour aggressiveness and metastasis. Here we investigated the levels of naturally occurring anti-glycan antibodies to Globo H in blood plasma obtained from high-grade serous ovarian cancer patients (SOC) and women without gynaecological malignancies (control) using suspension glycan array technology employing chemically synthesized glycans as antibody targets. We found that anti-human Globo H IgG antibodies were able to significantly discriminate SOC from controls (P anti-Globo H antibodies highly correlated (r = 0.992). The incubation of plasma-derived anti-glycan antibodies with chemically synthesized (presented on fluorescence microspheres) and native Globo H (expressed on Globo H-positive cell lines) revealed strong reactivity of naturally occurring human anti-Globo H antibodies towards its antigen expressed on ovarian cancer cells. Our data demonstrate that human plasma-derived antibodies to Globo H as well as the presence of the antigen might be considered as therapeutic option in ovarian cancer.

Mesenteric vascular occlusion: a new diagnostic method using a radiolabeled monoclonal antibody reactive with platelets

International Nuclear Information System (INIS)

Oster, Z.H.; Som, P.; Zamora, P.O.

1989-01-01

A new method for diagnosing mesenteric vaso-occlusive bowel disease with the use of radioimmunoscintigraphy was developed and tested in experimental models of arterial and venous disease, as well as in a model simulating bowel strangulation. The method involves the use of a monoclonal antibody fragment mixture that binds to platelets. The antibody was labeled with technetium-99m, and imaging was performed with a gamma camera in the planar and single photon emission computed tomography modes. This method allowed visualization of areas of ischemia of 1-6 hours duration in bowel loops in 19 dogs 90-180 minutes after injection of the radiolabeled antibody. No bowel radioactivity accumulation occurred in dogs that underwent the same surgical procedure but were given a nonspecific Tc-99m-labeled antibody or in normal dogs given the specific antibody. It appears that the radiolabeled antibody used, which has higher reactivity with human platelets than with dog platelets, will be a good agent for noninvasive diagnosis of mesenteric vaso-occlusive disease in humans. It may also play a role in the intraoperative determination of the extent and location of ischemic bowel segments

Enzyme-labeled Antigen Method: Development and Application of the Novel Approach for Identifying Plasma Cells Locally Producing Disease-specific Antibodies in Inflammatory Lesions

International Nuclear Information System (INIS)

Mizutani, Yasuyoshi; Shiogama, Kazuya; Onouchi, Takanori; Sakurai, Kouhei; Inada, Ken-ichi; Tsutsumi, Yutaka

2016-01-01

In chronic inflammatory lesions of autoimmune and infectious diseases, plasma cells are frequently observed. Antigens recognized by antibodies produced by the plasma cells mostly remain unclear. A new technique identifying these corresponding antigens may give us a breakthrough for understanding the disease from a pathophysiological viewpoint, simply because the immunocytes are seen within the lesion. We have developed an enzyme-labeled antigen method for microscopic identification of the antigen recognized by specific antibodies locally produced in plasma cells in inflammatory lesions. Firstly, target biotinylated antigens were constructed by the wheat germ cell-free protein synthesis system or through chemical biotinylation. Next, proteins reactive to antibodies in tissue extracts were screened and antibody titers were evaluated by the AlphaScreen method. Finally, with the enzyme-labeled antigen method using the biotinylated antigens as probes, plasma cells producing specific antibodies were microscopically localized in fixed frozen sections. Our novel approach visualized tissue plasma cells that produced 1) autoantibodies in rheumatoid arthritis, 2) antibodies against major antigens of Porphyromonas gingivalis in periodontitis or radicular cyst, and 3) antibodies against a carbohydrate antigen, Strep A, of Streptococcus pyogenes in recurrent tonsillitis. Evaluation of local specific antibody responses expectedly contributes to clarifying previously unknown processes in inflammatory disorders

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

Science.gov (United States)

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

2013-01-01

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

Thyroid Antibodies

Science.gov (United States)

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

Lack of radioimmunodetection and complications associated with monoclonal anticarcinoembryonic antigen antibody cross-reactivity with an antigen on circulating cells

International Nuclear Information System (INIS)

Dillman, R.O.; Beauregard, J.C.; Sobol, R.E.; Royston, I.; Bartholomew, R.M.; Hagan, P.S.; Halpern, S.E.

1984-01-01

Characterization of several high-affinity murine monoclonal anticarcinoembryonic antigen (CEA) antibodies suggested good specificity except for cross-reactivity with an antigen on granulocytes and erythrocytes which was different from the previously described normal cross-reacting antigen of granulocytes. In vivo studies in athymic mice using an indium conjugate of an anti-CEA monoclonal antibody (MoAb) revealed excellent specific uptake in colorectal carcinoma xenografts. Studies were conducted in humans to determine the limitations produced by the cross-reactivity with granulocytes and erythrocytes. Patients with metastatic colorectal cancer received 3 to 6 mg of anti-CEA MoAb over 10 min or 2 hr. In five of six trials, the MoAb infusion was associated with a 40 to 90% decrease in circulating granulocytes and systemic toxicity including fever, rigors, and emesis. One patient had no change in cell count and had no toxicity. Radionuclide scans with 111 In-anti-CEA MoAb showed marked uptake in the spleen when cells were eliminated, and in the liver, especially when pretreatment CEA levels were high. Metastatic tumor sites failed to concentrate the isotope. This study emphasizes the potential limitations for radioimmunodetection and/or radioimmunotherapy imposed by reactivity with circulating cells, and suggests that certain toxic reactions associated with MoAb infusions are related to destruction of circulating cells rather than allergic reactions to mouse protein. It also emphasizes how variables such as dose and binding affinity of antibody, radioisotope used, and assessment at different observation points can obscure lack of antibody specificity

Lack of radioimmunodetection and complications associated with monoclonal anticarcinoembryonic antigen antibody cross-reactivity with an antigen on circulating cells

Energy Technology Data Exchange (ETDEWEB)

Dillman, R.O.; Beauregard, J.C.; Sobol, R.E.; Royston, I.; Bartholomew, R.M.; Hagan, P.S.; Halpern, S.E.

1984-05-01

Characterization of several high-affinity murine monoclonal anticarcinoembryonic antigen (CEA) antibodies suggested good specificity except for cross-reactivity with an antigen on granulocytes and erythrocytes which was different from the previously described normal cross-reacting antigen of granulocytes. In vivo studies in athymic mice using an indium conjugate of an anti-CEA monoclonal antibody (MoAb) revealed excellent specific uptake in colorectal carcinoma xenografts. Studies were conducted in humans to determine the limitations produced by the cross-reactivity with granulocytes and erythrocytes. Patients with metastatic colorectal cancer received 3 to 6 mg of anti-CEA MoAb over 10 min or 2 hr. In five of six trials, the MoAb infusion was associated with a 40 to 90% decrease in circulating granulocytes and systemic toxicity including fever, rigors, and emesis. One patient had no change in cell count and had no toxicity. Radionuclide scans with /sup 111/In-anti-CEA MoAb showed marked uptake in the spleen when cells were eliminated, and in the liver, especially when pretreatment CEA levels were high. Metastatic tumor sites failed to concentrate the isotope. This study emphasizes the potential limitations for radioimmunodetection and/or radioimmunotherapy imposed by reactivity with circulating cells, and suggests that certain toxic reactions associated with MoAb infusions are related to destruction of circulating cells rather than allergic reactions to mouse protein. It also emphasizes how variables such as dose and binding affinity of antibody, radioisotope used, and assessment at different observation points can obscure lack of antibody specificity.

Combining Phage and Yeast Cell Surface Antibody Display to Identify Novel Cell Type-Selective Internalizing Human Monoclonal Antibodies.

Science.gov (United States)

Bidlingmaier, Scott; Su, Yang; Liu, Bin

2015-01-01

Using phage antibody display, large libraries can be generated and screened to identify monoclonal antibodies with affinity for target antigens. However, while library size and diversity is an advantage of the phage display method, there is limited ability to quantitatively enrich for specific binding properties such as affinity. One way of overcoming this limitation is to combine the scale of phage display selections with the flexibility and quantitativeness of FACS-based yeast surface display selections. In this chapter we describe protocols for generating yeast surface antibody display libraries using phage antibody display selection outputs as starting material and FACS-based enrichment of target antigen-binding clones from these libraries. These methods should be widely applicable for the identification of monoclonal antibodies with specific binding properties.

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

Directory of Open Access Journals (Sweden)

Lanzillo R

2014-10-01

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

Serology indicates cytomegalovirus infection is associated with varicella-zoster virus reactivation.

Science.gov (United States)

Ogunjimi, Benson; Theeten, Heidi; Hens, Niel; Beutels, Philippe

2014-05-01

Varicella-zoster virus (VZV) causes chickenpox after which the virus remains latent in neural ganglia. Subsequent reactivation episodes occur, leading mainly to subclinical detection of VZV, but also to the clinical entity herpes zoster. These reactivations are known to occur most frequently amongst immunocompromised individuals, but the incidence of herpes zoster is also known to increase with age, supposedly as a consequence of immunosenescence. Our analysis aims to explore associations between cytomegalovirus (CMV) infection and VZV reactivation by analyzing VZV-specific antibody titers as a function of age, gender, and CMV serostatus. The analysis was repeated on measles and parvovirus B19 antibody titers. At the time of the observations, measles virus circulation was virtually eliminated, whereas parvovirus B19 circulated at lower levels than VZV. Multiple linear regression analyses, using the log-transformed antibody titers, identified a positive association between ageing and VZV antibody titers suggesting that ageing increasingly stimulates VZV reactivation. CMV infection further amplified the positive association between ageing and the reactivation rate. A negative association between CMV infection and VZV antibody titers was found in young individuals, thereby supporting the hypothesis that CMV infection may have a negative effect on the number of B-cells. However, no associations between CMV infection and measles or parvovirus B19 antibody titers occurred, but ageing tended to be associated with a decrease in the antibody titer against parvovirus B19. The combined results thus suggest that both CMV-dependent and CMV-independent immunosenescence occurs. This is supported by an in-depth analysis of VZV, measles and parvovirus B19 antibody titers. © 2013 Wiley Periodicals, Inc.

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

Directory of Open Access Journals (Sweden)

Zhao Qinjian

2012-02-01

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

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

DEFF Research Database (Denmark)

Jakobsen, P.H.; Theander, T.G.; Hvid, L

1996-01-01

Synthetic P. falciparum peptides were evaluated as tools in epidemiological investigations of malaria. Plasma IgM and IgG antibody reactivities against synthetic peptides covering sequences of glutamate-rich protein (GLURP) and acidic-basic repeat antigen (ABRA) were measured by ELISA...

Vaccination with Shigella flexneri 2a conjugate induces type 2a and cross-reactive type 6 antibodies in humans but not in mice.

Science.gov (United States)

Farzam, Nahid; Ramon-Saraf, Reut; Banet-Levi, Yonit; Lerner-Geva, Liat; Ashkenazi, Shai; Kubler-Kielb, Joanna; Vinogradov, Evgeny; Robbins, John B; Schneerson, Rachel

2017-09-05

Shigella flexneri (S. flexneri) 6 has emerged as an important cause of shigellosis. Our efficacy study of Shigella sonnei and S. flexneri 2a O-specific polysaccharide (O-SP) conjugates in 1-4year-olds had too few S. flexneri 2a cases for efficacy evaluation but surprisingly showed protection of 3-4year-olds, S. flexneri 2a-recipients, from S. flexneri 6 infection. To investigate this cross-protection antibodies to both Shigella types were investigated in all sera remaining from previous studies. Twenty to 30% of 3-44year-old humans injected with S. flexneri 2a conjugate responded with ≥4-fold increases of IgG anti type 6, p<0.00001. The specificity of these antibodies was shown by inhibition studies. S. flexneri 6 infection of 2 children induced besides S. flexneri 6, also S. flexneri 2a antibodies, at levels of S. flexneri 2a vaccinees. S. flexneri 2a antibodies induced by S. flexneri 6 conjugates could not be studied since no such conjugate was assessed in humans and mice responded almost exclusively to the O-SP of the injected conjugate, with no cross-reactive antibodies. Our results indicate induction of cross-reactive protective antibodies. The O-acetylated disaccharide shared by S. flexneri 6 and 2a O-SPs, is the likely basis for their cross-reactivity. S. flexneri 6 O-SP conjugates, alone and in combination with S. flexneri 2a, merit further investigation for broad S. flexneri protection. Published by Elsevier Ltd.

Cross-reactivity of antibodies against PorA after vaccination with a meningococcal B outer membrane vesicle vaccine

NARCIS (Netherlands)

Vermont, C. L.; van Dijken, H. H.; Kuipers, A. J.; van Limpt, C. J. P.; Keijzers, W. C. M.; van der Ende, A.; de Groot, R.; van Alphen, L.; van den Dobbelsteen, G. P. J. M.

2003-01-01

The cross-reactivity of PorA-specific antibodies induced by a monovalent P1.7-2,4 (MonoMen) and/or a hexavalent (HexaMen) meningococcal B outer membrane vesicle vaccine (OMV) in toddlers and school children was studied by serum bactericidal assays (SBA). First, isogenic vaccine strains and

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

DEFF Research Database (Denmark)

Sun, Jing; Kudahl, Ulrich J.; Simon, Christian

2014-01-01

Influenza viruses continue to cause substantial morbidity and mortality worldwide. Fast gene mutation on surface proteins of influenza virus result in increasing resistance to current vaccines and available antiviral drugs. Broadly neutralizing antibodies (bnAbs) represent targets for prophylacti......, and differences between historical influenza strains, we enhance our preparedness and the ability to respond to the emerging pandemic threats....... a method to assess the likely cross-reactivity potential of bnAbs for influenza strains, either newly emerged or existing. Our method catalogs influenza strains by a new concept named discontinuous peptide, and then provide assessment of cross-reactivity. Potentially cross-reactive strains are those...

Identifying cognitive predictors of reactive and proactive aggression

NARCIS (Netherlands)

Brugman, S.; Lobbestael, J.; Arntz, A.R.; Cima, M.; Schumann, T.; Dambacher, F.

2015-01-01

The aim of this study was to identify implicit cognitive predictors of aggressive behavior. Specifically, the predictive value of an attentional bias for aggressive stimuli and automatic association of the self and aggression was examined for reactive and proactive aggressive behavior in a

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

DEFF Research Database (Denmark)

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

2000-01-01

and their neutralising activity was evident. Binding kinetic analyses by plasmon resonance identified differences in the dissociation rate constant (kd) as a possible explanation for the different reactivity levels of the MAbs. The Ig variable heavy (VH) and light (V kappa) domain gene sequences of the three hybridomas...... were compared. The inferred amino acid sequence of the two neutralising antibody VH domains differed by three amino acid residues (97% identity) and only one residue difference was evident in the Vk. domains. In contrast, IP1H3 shared only 38 and 39% identity with the 3F1A2 and 3F1H10 VH domains...... respectively and 49 and 50% identity with the 3F1A2 and 3F1H10 VK domains respectively. The neutralising antibodies were produced by hybridomas originating from the same fusion and the high nucleotide sequence homology of the variable Ig gene regions indicated that the plasma cell partners of the hybridomas...

Deciphering allogeneic antibody response against native and denatured HLA epitopes in organ transplantation.

Science.gov (United States)

Visentin, Jonathan; Guidicelli, Gwendaline; Moreau, Jean-François; Lee, Jar-How; Taupin, Jean-Luc

2015-07-01

Anti-HLA donor-specific antibodies are deleterious for organ transplant survival. Class I HLA donor-specific antibodies are identified by using the Luminex single antigen beads (LSAB) assay, which also detects anti-denatured HLA antibodies (anti-dHLAs). Anti-dHLAs are thought to be unable to recognize native HLA (nHLA) on the cell surface and therefore to be clinically irrelevant. Acid denaturation of nHLA on LSAB allows anti-dHLAs to be discriminated from anti-nHLAs. We previously defined a threshold for the ratio between mean fluorescence intensity against acid-treated (D for denaturation) and nontreated (N) LSAB, D ≥ 1.2 N identifying the anti-dHLAs. However, some anti-dHLAs remained able to bind nHLA on lymphocytes in flow cytometry crossmatches, and some anti-nHLAs conserved significant reactivity toward acid-treated LSAB. After depleting serum anti-nHLA reactivity with HLA-typed cells, we analyzed the residual LSAB reactivity toward nontreated and acid-treated LSABs, and then evaluated the ability of antibodies to recognize nHLA alleles individually. We observed that sera can contain mixtures of anti-nHLAs and anti-dHLAs, or anti-nHLAs recognizing acid-resistant epitopes, all possibly targeting the same allele(s). Therefore, the anti-HLA antibody response can be highly complex and subtle, as is the accurate identification of pathogenic anti-HLA antibodies in human serum. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Immune reactivities against gums.

Science.gov (United States)

Vojdani, Aristo; Vojdani, Charlene

2015-01-01

Different kinds of gums from various sources enjoy an extremely broad range of commercial and industrial use, from food and pharmaceuticals to printing and adhesives. Although generally recognized as safe by the US Food and Drug Administration (FDA), gums have a history of association with sensitive or allergic reactions. In addition, studies have shown that gums have a structural, molecular similarity to a number of common foods. A possibility exists for cross-reactivity. Due to the widespread use of gums in almost every aspect of modern life, the overall goal of the current investigation was to determine the degree of immune reactivity to various gum antigens in the sera of individuals representing the general population. The study was a randomized, controlled trial. 288 sera purchased from a commercial source. The sera was screened for immunoglobulin G (IgG) and immunoglobulin E (IgE) antibodies against extracts of mastic gum, carrageenan, xantham gum, guar gum, gum tragacanth, locust bean gum, and β-glucan, using indirect enzyme-linked immunosorbent assay (ELISA) testing. For each gum antigen, inhibition testing was performed on the 4 sera that showed the highest IgG and IgE immune reactivity against the different gums used in the study. Inhibition testing on these same sera for sesame albumin, lentil, corn, rice, pineapple, peanut, pea protein, shrimp, or kidney bean was used to determine the cross-reactivity of these foods with the gum. Of the 288 samples, 4.2%-27% of the specimens showed a significant elevation in IgG antibodies against various gums. Only 4 of 288, or 1.4%, showed a simultaneous elevation of the IgG antibody against all 7 gum extracts. For the IgE antibody, 15.6%-29.1% of the specimens showed an elevation against the various gums. A significant percentage of the specimens, 12.8%, simultaneously produced IgE antibodies against all 7 tested extracts. Overall, the percentage of elevation in IgE antibodies against different gum extracts, with

Development of antibody against sulfamethazine

International Nuclear Information System (INIS)

Li Ziying; Xi Wenge; Liu Yibing; Zhang Liling; Guo Weizheng; Han Shiquan

2004-01-01

Sulfamethazine (SMT) is widely used to treat bacterial and protozoan infections in food animals. So its residue has been detected in various food products, and in Europe, the tolerance level for sulfonamides in meat and milk is 100 ng/g. To ensure that residues in animal food products do not exceed this limit, a simple, sensitive, and rapid method to determinate their residues in animal tissues is needed. In this paper the development of polyclonal or monoclonal antibodies against sulfamethazine (SMT) and a simplified method to identify residual sulfamethazine by radio immunoassay (RIA) is presented. Polyclonal antibodies (PcAbs) against sulfamethazine (SMT) were obtained by immunizing rabbits with SMT-conjugated bovine serum albumin (BSA). The association constants (Ka) of the PcAbs were higher than 108 and the cross-reactivities with Sulfadiazine(SD), Sulfaquinoxaline(SQX) which were structurally related compounds were lower than 0.05%(RIA). Simultaneous, six strains of hybridoma cell were prepared which can secrete monoclonal antibodies (McAbs) against SMT . The Ka of the McAbs against SMT were higher than 107 and the cross-reactivities with SD, SQX were lower than 0.1%(RIA). (authors)

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

International Nuclear Information System (INIS)

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

1994-01-01

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

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

Science.gov (United States)

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

2017-10-01

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

Variant proteins stimulate more IgM+ GC B-cells revealing a mechanism of cross-reactive recognition by antibody memory.

Science.gov (United States)

Burton, Bronwen R; Tennant, Richard K; Love, John; Titball, Richard W; Wraith, David C; White, Harry N

2018-05-01

Vaccines induce memory B-cells that provide high affinity secondary antibody responses to identical antigens. Memory B-cells can also re-instigate affinity maturation, but how this happens against antigenic variants is poorly understood despite its potential impact on driving broadly protective immunity against pathogens such as Influenza and Dengue. We immunised mice sequentially with identical or variant Dengue-virus envelope proteins and analysed antibody and germinal-centre (GC) responses. Variant protein boosts induced GC with higher proportions of IgM+ B-cells. The most variant protein re-stimulated GCs with the highest proportion of IgM+ cells with the most diverse, least mutated V-genes and with a slower but efficient serum antibody response. Recombinant antibodies from GC B-cells showed a higher affinity for the variant antigen than antibodies from a primary response, confirming a memory origin. This reveals a new process of antibody memory, that IgM memory cells with fewer mutations participate in secondary responses to variant antigens, demonstrating how the hierarchical structure of B-cell memory is used and indicating the potential and limits of cross-reactive antibody based immunity. © 2018, Burton et al.

Isolation of Mal d 1 and Api g 1 - specific recombinant antibodies from mouse IgG Fab fragment libraries - Mal d 1-specific antibody exhibits cross-reactivity against Bet v 1.

Science.gov (United States)

Haka, Jaana; Niemi, Merja H; Iljin, Kristiina; Reddy, Vanga Siva; Takkinen, Kristiina; Laukkanen, Marja-Leena

2015-05-27

Around 3-5% of the population suffer from IgE-mediated food allergies in Western countries and the number of food-allergenic people is increasing. Individuals with certain pollen allergies may also suffer from a sensitisation to proteins in the food products. As an example a person sensitised to the major birch pollen allergen, Bet v 1, is often sensitised to its homologues, such as the major allergens of apple, Mal d 1, and celery, Api g 1, as well. Development of tools for the reliable, sensitive and quick detection of allergens present in various food products is essential for allergic persons to prevent the consumption of substances causing mild and even life-threatening immune responses. The use of monoclonal antibodies would ensure the specific detection of the harmful food content for a sensitised person. Mouse IgG antibody libraries were constructed from immunised mice and specific recombinant antibodies for Mal d 1 and Api g 1 were isolated from the libraries by phage display. More detailed characterisation of the resulting antibodies was carried out using ELISA, SPR experiments and immunoprecipitation assays. The allergen-specific Fab fragments exhibited high affinity towards the target recombinant allergens. Furthermore, the Fab fragments also recognised native allergens from natural sources. Interestingly, isolated Mal d 1-specific antibody bound also to Bet v 1, the main allergen eliciting the cross-reactivity syndrome between the birch pollen and apple. Despite the similarities in Api g 1 and Bet v 1 tertiary structures, the isolated Api g 1-specific antibodies showed no cross-reactivity to Bet v 1. Here, high-affinity allergen-specific recombinant antibodies were isolated with interesting binding properties. With further development, these antibodies can be utilised as tools for the specific and reliable detection of allergens from different consumable products. This study gives new preliminary insights to elucidate the mechanism behind the pollen

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

Science.gov (United States)

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

2017-10-01

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

Monoclonal Antibodies to Intracellular Stages of Cryptosporidium parvum Define Life Cycle Progression In Vitro.

Science.gov (United States)

Wilke, Georgia; Ravindran, Soumya; Funkhouser-Jones, Lisa; Barks, Jennifer; Wang, Qiuling; VanDussen, Kelli L; Stappenbeck, Thaddeus S; Kuhlenschmidt, Theresa B; Kuhlenschmidt, Mark S; Sibley, L David

2018-06-27

Among the obstacles hindering Cryptosporidium research is the lack of an in vitro culture system that supports complete life development and propagation. This major barrier has led to a shortage of widely available anti- Cryptosporidium antibodies and a lack of markers for staging developmental progression. Previously developed antibodies against Cryptosporidium were raised against extracellular stages or recombinant proteins, leading to antibodies with limited reactivity across the parasite life cycle. Here we sought to create antibodies that recognize novel epitopes that could be used to define intracellular development. We identified a mouse epithelial cell line that supported C. parvum growth, enabling immunization of mice with infected cells to create a bank of monoclonal antibodies (MAbs) against intracellular parasite stages while avoiding the development of host-specific antibodies. From this bank, we identified 12 antibodies with a range of reactivities across the parasite life cycle. Importantly, we identified specific MAbs that can distinguish different life cycle stages, such as trophozoites, merozoites, type I versus II meronts, and macrogamonts. These MAbs provide valuable tools for the Cryptosporidium research community and will facilitate future investigation into parasite biology. IMPORTANCE Cryptosporidium is a protozoan parasite that causes gastrointestinal disease in humans and animals. Currently, there is a limited array of antibodies available against the parasite, which hinders imaging studies and makes it difficult to visualize the parasite life cycle in different culture systems. In order to alleviate this reagent gap, we created a library of novel antibodies against the intracellular life cycle stages of Cryptosporidium We identified antibodies that recognize specific life cycle stages in distinctive ways, enabling unambiguous description of the parasite life cycle. These MAbs will aid future investigation into Cryptosporidium biology and

Cross-reactivity among antigens of different air-borne fungi detected by ELISA using five monoclonal antibodies against Penicillium notatum.

Science.gov (United States)

Shen, H D; Lin, W L; Chen, R J; Han, S H

1990-10-01

Cross-reactivity among antigens of 12 genera of air-borne fungi, 13 species of Penicillium, and 5 species of Aspergillus was studied by ELISA using five monoclonal antibodies (MoAbs) against Penicillium notatum. Epitopes recognized by all the five MoAbs were susceptible to treatment of mild periodate oxidation and may therefore be associated with carbohydrates. Furthermore, our results showed that there is cross-reactivity among antigens of Penicillium, Aspergillus, and Eurotium species. By using these MoAbs, cross reactivity was not detected between antigens of Penicillium notatum and antigens of Fusarium solani, Alternaria porri, Cladosporium cladosporoides, Curvularia species, Nigrospora species, Aureobasidium pullulans, Wallemia species, Rhizopus arrhizus, and Candida albicans. Cross-reactivity among antigens of 11 species of Penicillium and 5 species of Aspergillus could be detected by ELISA using one of the five MoAbs (MoAb P15). The fact that there may be cross-reactivity among antigens of closely related fungi species should be considered in the diagnosis and treatment of mold allergic diseases.

Antigenic Fingerprinting following Primary RSV Infection in Young Children Identifies Novel Antigenic Sites and Reveals Unlinked Evolution of Human Antibody Repertoires to Fusion and Attachment Glycoproteins.

Directory of Open Access Journals (Sweden)

Sandra Fuentes

2016-04-01

Full Text Available Respiratory Syncytial Virus (RSV is the major cause of pneumonia among infants. Here we elucidated the antibody repertoire following primary RSV infection and traced its evolution through adolescence and adulthood. Whole genome-fragment phage display libraries (GFPDL expressing linear and conformational epitopes in the RSV fusion protein (F and attachment protein (G were used for unbiased epitope profiling of infant sera prior to and following RSV infection. F-GFPDL analyses demonstrated modest changes in the anti-F epitope repertoires post-RSV infection, while G-GFPDL analyses revealed 100-fold increase in number of bound phages. The G-reactive epitopes spanned the N- and C-terminus of the G ectodomain, along with increased reactivity to the central conserved domain (CCD. Panels of F and G antigenic sites were synthesized to evaluate sera from young children (<2 yr, adolescents (14-18 yr and adults (30-45 yr in SPR real-time kinetics assays. A steady increase in RSV-F epitope repertoires from young children to adults was observed using peptides and F proteins. Importantly, several novel epitopes were identified in pre-fusion F and an immunodominant epitope in the F-p27. In all age groups, antibody binding to pre-fusion F was 2-3 folds higher than to post-fusion form. For RSV-G, antibody responses were high following early RSV infection in children, but declined significantly in adults, using either G proteins or peptides. This study identified unlinked evolution of anti-F and anti G responses and supportive evidence for immune pressure driven evolution of RSV-G. These findings could help development of effective countermeasures including vaccines.

Identification of anti-CD98 antibody mimotopes for inducing antibodies with antitumor activity by mimotope immunization.

Science.gov (United States)

Saito, Misa; Kondo, Masahiro; Ohshima, Motohiro; Deguchi, Kazuki; Hayashi, Hideki; Inoue, Kazuyuki; Tsuji, Daiki; Masuko, Takashi; Itoh, Kunihiko

2014-04-01

A mimotope is an antibody-epitope-mimicking peptide retrieved from a phage display random peptide library. Immunization with antitumor antibody-derived mimotopes is promising for inducing antitumor immunity in hosts. In this study, we isolated linear and constrained mimotopes from HBJ127, a tumor-suppressing anti-CD98 heavy chain mAb, and determined their abilities for induction of antitumor activity equal to that of the parent antibody. We detected elevated levels of antipeptide responses, but failed to detect reactivity against native CD98-expressing HeLa cells in sera of immunized mice. Phage display panning and selection of mimotope-immunized mouse spleen-derived antibody Fab library showed that HeLa cell-reactive Fabs were successfully retrieved from the library. This finding indicates that native antigen-reactive Fab clones represented an undetectable minor population in mimotope-induced antibody repertoire. Functional and structural analysis of retrieved Fab clones revealed that they were almost identical to the parent antibody. From these results, we confirmed that mimotope immunization was promising for retrieving antitumor antibodies equivalent to the parent antibody, although the co-administration of adjuvant compounds such as T-cell epitope peptides and Toll-like receptor 4 agonist peptides is likely to be necessary for inducing stronger antitumor immunity than mimotope injection alone. © 2014 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

Antibody Arrays Identify Potential Diagnostic Markers of Hepatocellular Carcinoma

Directory of Open Access Journals (Sweden)

Brian J. Peter

2008-01-01

Full Text Available Hepatocellular carcinoma (HCC is the third leading cause of cancer deaths worldwide. Effective treatment of HCC patients is hampered by the lack of sensitive and specific diagnostic markers of HCC. Alpha-fetoprotein (AFP, the currently used HCC marker, misses 30%–50% of HCC patients, who therefore remain undiagnosed and untreated. In order to identify novel diagnostic markers that can be used individually or in combination with AFP, we used an antibody array platform to detect the levels of candidate proteins in the plasma of HCC patients (n = 48 and patients with chronic hepatitis B or C viral infections (n = 19 (both of which are the major risk factors of HCC. We identified 7 proteins that significantly differentiate HCC patients from hepatitis patients (p < 0.05 (AFP, CTNNB, CSF1, SELL, IGFBP6, IL6R, and VCAM1.Importantly, we also identified 8 proteins that significantly differentiate HCC patients with ‘normal’ levels of AFP (<20 ng/ml from hepatitis patients (p < 0.05 (IL1RN, IFNG, CDKN1A, RETN, CXCL14, CTNNB, FGF2, and SELL. These markers are potentially important complementary markers to AFP. Using an independent immunoassay method in an independent group of 23 HCC patients and 22 hepatitis patients, we validated that plasma levels of CTNNB were significantly higher in the HCC group (p = 0.020. In conclusion, we used an antibody array platform to identify potential circulating diagnostic markers of HCC, some of which may be valuable when used in combination with AFP. The clinical utility of these newly identified HCC diagnostic markers needs to be systematically evaluated.

Production and characterization of monoclonal antibodies against mink leukocytes

DEFF Research Database (Denmark)

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

1997-01-01

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

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

Directory of Open Access Journals (Sweden)

Hiroshi Miyakawa

2006-01-01

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

Identifying anti-Toxocara IgG antibodies in horses of Mexico

Directory of Open Access Journals (Sweden)

R. Heredia

Full Text Available ABSTRACT Both the presence of owned dogs and stray dogs allows the spread of Toxocara, a parasite whose eggs can be found in soil, water and food. Animals, including horses, serve as definitive and paratenic hosts. In México, where consumption of horse meat is common, Toxocara is a zoonotic parasite. The aim of this study was to identify the presence of anti-Toxocara antibodies in work horses and horses intended for human consumption by ELISA. ELISA was chosen for analysis as paratenic hosts do not shed Toxocara eggs in their feces. Blood samples were collected from a total of 188 horses, 94 of which were work horses and 94 horses from the slaughter house. Samples were analyzed by ELISA, and the general equine seroprevalence was found to be 44.6% (n = 188. Adult horses for slaughter had a 61.7% greater presence of anti-Toxocara antibodies (p = 0.006. Toxocara IgG antibodies were found in horses, confirming that horses are paratenic hosts and possible sources of infection for other animals and people.

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

International Nuclear Information System (INIS)

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

1987-01-01

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

Mapping the stem cell state: eight novel human embryonic stem and embryonal carcinoma cell antibodies

DEFF Research Database (Denmark)

Wright, A; Andrews, N; Bardsley, K

2011-01-01

The antigenic profile of human embryonic stem (ES) and embryonal carcinoma (EC) cells has served as a key element of their characterization, with a common panel of surface and intracellular markers now widely used. Such markers have been used to identify cells within the 'undifferentiated state...... of reactivity for all antibodies against both ES and EC cells, suggesting that these markers will afford recognition of unique sub-states within the undifferentiated stem cell compartment....... and EC cells, and herein describe their characterization. The reactivity of these antibodies against a range of cell lines is reported, as well as their developmental regulation, basic biochemistry and reactivity in immunohistochemistry of testicular germ cell tumours. Our data reveal a range...

Passive immunization against Cryptococcus neoformans with an isotype-switch family of monoclonal antibodies reactive with cryptococcal polysaccharide.

Science.gov (United States)

Sanford, J E; Lupan, D M; Schlageter, A M; Kozel, T R

1990-01-01

The in vivo properties of an immunoglobulin isotype-switch family of monoclonal antibodies specific for the polysaccharide capsule of Cryptococcus neoformans were examined in a murine model of cryptococcosis. Subclass-switch variants were isolated by sequential sublining of an immunoglobulin G subclass 1 (IgG1)-secreting cell line. Antibodies of the IgG1, IgG2a, and IgG2b isotypes with identical reactivities with cryptococcal polysaccharide were prepared. The antibodies had the distinct biological properties associated with the heavy chains of each respective isotype. The antibodies were used prophylactically or therapeutically in an attempt to alter the course of cryptococcal infection in mice. Survival of mice and a tissue census of the numbers of viable cryptococci in the lung, spleen, and brain were used as indicators of efficacy. Passive immunization with the IgG2a and IgG2b antibodies effected a reduction in the numbers of cryptococci in lung and spleen. Passive immunization with the IgG1 antibody was markedly less effective. Passive immunization had little or no effect on the numbers of cryptococci in brain tissue, regardless of the immunoglobulin isotype. Despite apparent efficacy with regard to reduction in the numbers of yeast cells in the lung and spleen, the results showed no improvement in survival from murine cryptococcosis. Our results indicate that passive immunization produces a modest effect on the course of murine cryptococcosis in tissues other than brain. However, under the experimental conditions used, such treatment does not have a measurable impact on the ultimate outcome of the infection. PMID:2341184

Description of 15 DNA-positive and antibody-negative "window-period" blood donations identified during prospective screening for Babesia microti.

Science.gov (United States)

Moritz, Erin D; Tonnetti, Laura; Hewins, Mary Ellen; Berardi, Victor P; Dodd, Roger Y; Stramer, Susan L

2017-07-01

Blood donation screening detecting only antibodies fails to identify donors in the earliest stage of infection, before a detectable immunologic response, that is, the "window period" (WP). We present data on WP donations identified during prospective screening for Babesia microti, a transfusion-transmissible parasite of increasing concern in the United States. Blood donations collected in Connecticut, Massachusetts, Minnesota, and Wisconsin were screened using polymerase chain reaction (PCR) and arrayed fluorescence immunoassay (AFIA) to detect B. microti DNA and antibodies, respectively. Parasite loads were estimated using quantitative PCR. Red blood cell (RBC) samples were inoculated into hamsters to assess infectivity. Donors screening reactive were indefinitely deferred, tested by supplemental methods, and followed to assess DNA and antibody clearance. Demographic data from WP donors (i.e., those screening PCR positive and AFIA negative) were compared to data from other positive donors. Of 220,479 donations screened from June 2012 to August 2016, a total of 700 were positive, of which 15 (2% of positive donations or 1 per 14,699 screened donations) were confirmed WP donations. The median estimated parasite load in WP donations was 350 parasites/mL, no different than AFIA-positive and PCR-positive donors. Parasite loads in RBC samples from WP units ranged from 14 to 11,022 parasites/mL; RBC samples from three of 10 (30%) WP donations infected hamsters. The mean age of WP donors was 48 years (range, 17-75 years); three (20%) were female. WP donor demographics did not differ significantly from demographics of other donors. We report one per 15,000 B. microti WP infections in blood donors in endemic areas, demonstrating the importance of nucleic acid testing to mitigate the risk of transfusion-transmitted babesiosis. © 2017 AABB.

Toxoplasmosis serology: an efficient hemagglutination procedure to detect IgG and IgM antibodies

Directory of Open Access Journals (Sweden)

M.E. Camargo

1989-08-01

Full Text Available In search of an efficient but simple, low cost procedure for the serodiagnosis of Toxoplasmosis, especially suited for routine laboratories facing technical and budget limitations as in less developed countries, the diagnostic capability of Hematoxo® , an hemagglutination test for toxoplasmosis, was evaluated in relation to a battery of tests including IgG- and IgM-immunofluorescence tests, hemagglutination and an IgM-capture enzymatic assay. Detecting a little as 5 I.U. of IgG antitoxoplasma antibodies, Hematoxo® showed a straight agreement as to reactivity and non-reactivity for the 443 non-reactive and the 387 reactive serum samples, included in this study. In 23 cases presenting a serological pattern of acute toxoplasmosis and showing IgM antibodies, Hematoxo® could detect IgM antibodies in 18, indicated by negativation or a significant decrease in titers as a result of treating samples with 2-mercapto-ethanol. However, a neat increase in sensitivity for IgM specific antibodies could be achieved by previously removing IgG from the sample, as demonstrated in a series of acute toxoplasmosis sera. A simple procedure was developed for this purpose, by reconstituting a lyophilized suspension of Protein A - rich Staphylococcus with the lowest serum dilution to be tested. Of low cost and easy to perform, Hematoxo® affords not only a practical qualitative procedure for screening reactors and non-reactors, as in prenatal services, but also quantitative assays that permit to titrate antibodies as well as to identify IgM antibodies.

Characterization of a Broadly Reactive Anti-CD40 Agonistic Monoclonal Antibody for Potential Use as an Adjuvant.

Directory of Open Access Journals (Sweden)

Cameron Martin

Full Text Available Lack of safe and effective adjuvants is a major hindrance to the development of efficacious vaccines. Signaling via CD40 pathway leads to enhanced antigen processing and presentation, nitric oxide expression, pro-inflammatory cytokine expression by antigen presenting cells, and stimulation of B-cells to undergo somatic hypermutation, immunoglobulin class switching, and proliferation. Agonistic anti-CD40 antibodies have shown promising adjuvant qualities in human and mouse vaccine studies. An anti-CD40 monoclonal antibody (mAb, designated 2E4E4, was identified and shown to have strong agonistic effects on primary cells from multiple livestock species. The mAb recognize swine, bovine, caprine, and ovine CD40, and evoked 25-fold or greater proliferation of peripheral blood mononuclear cells (PBMCs from these species relative to cells incubated with an isotype control (p<0.001. In addition, the mAb induced significant nitric oxide (p<0.0001 release by bovine macrophages. Furthermore, the mAb upregulated the expression of MHC-II by PBMCs, and stimulated significant (p<0.0001 IL-1α, IL6, IL-8, and TNF-α expression by PBMCs. These results suggest that the mAb 2E4E4 can target and stimulate cells from multiple livestock species and thus, it is a potential candidate for adjuvant development. This is the first study to report an anti-swine CD40 agonistic mAb that is also broadly reactive against multiple species.

Influence of race/ethnic differences in pre-transplantation panel reactive antibody on outcomes in heart transplant recipients.

Science.gov (United States)

Morris, Alanna A; Cole, Robert T; Veledar, Emir; Bellam, Naveen; Laskar, S Raja; Smith, Andrew L; Gebel, Howard M; Bray, Robert A; Butler, Javed

2013-12-17

This study sought to investigate post-transplantation outcomes as a function of race and panel reactive antibody (PRA). PRA screening is used to determine the presence of pre-formed antibodies to population-wide human leukocyte antigens (HLAs) in patients being evaluated for heart transplantation (HT). Racial/ethnic differences in long-term survival after HT have been described. However, whether there are significant racial/ethnic differences in PRA among adults awaiting HT is poorly characterized. We identified patients age ≥18 years in the Organ Procurement and Transplantation database with race/ethnicity of white, black, Hispanic, or Asian and listed for HT between 2000 and 2012 (N = 19,704). A PRA value of ≥10% was used to define clinically meaningful sensitization. Blacks had a higher peak PRA than did all other groups and were more likely to be sensitized. Black HT recipients were more likely to experience graft failure than were Hispanic, white, and Asian recipients (31% vs. 27%, 26%, and 21%, respectively; p race (HR: 1.3; 95% confidence interval [CI]: 1.2 to 1.5), Hispanic ethnicity (HR: 1.2; 95% CI: 1.0 to 1.5), and sensitization (HR: 1.2; 95% CI: 1.1 to 1.4) remained predictors of higher rates of graft failure. Race/ethnicity and level of sensitization are important predictors of graft survival. Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Placental and colostral transfer of antibodies reactive with enteropathogenic Escherichia coli intimins α, β, or γ

Directory of Open Access Journals (Sweden)

Silvia P.N. Altman

2017-11-01

Full Text Available Objective: Intimins are protein adhesins of enteropathogenic Escherichia coli and enterohemorrhagic E. coli capable of inducing attachment and effacement lesions in enterocytes. Anti-intimin antibodies are important for the protection from enteropathogenic E. coli and enterohemorrhagic E. coli infections because these antibodies inhibit bacterial adhesion and impair the initial step of the pathogenesis. We studied the transfer of maternal anti-intimin antibodies from healthy Brazilian mothers to their newborns through the placenta and colostrum. Methods: Serum immunoglobulin G and secretory immunoglobulin A antibodies against conserved and variable regions of intimins α, β, and γ were analyzed using an enzyme linked-immunosorbent assay in the blood and colostrum from 45 healthy women as well as cord blood serum samples from their newborns. Results: The concentrations of antibodies reactive with α intimin were significantly lower than those of anti-γ and anti-conserved intimin antibodies in the colostrum samples. IgG serum antibodies reactive with all the subtypes of intimins were transferred to the newborns, but the concentrations of anti-conserved intimin serum antibodies were significantly higher in mothers and newborns than concentrations of antibodies against variable regions. The patterns of IgG transfer from mothers to newborns were similar for all anti-intimin antibodies. These values are similar to the percentage transference of total IgG. Conclusions: Anti-intimin antibodies are transferred from mothers to newborns through the placenta, and reinforce the protection provided by breastfeeding against diarrheagenic E. coli infections. Resumo: Objetivo: As Intiminas são adesinas proteicas de Escherichia coli enteropatogênicas e enterohemorrágicas capazes de induzir as lesões “attaching and effacing” nos enterócitos. Anticorpos anti-intiminas são importantes para a proteção contra infecções por E. coli enteropatogênica e

Immunization with Clinical HIV-1 Env Proteins Induces Broad Antibody Dependent Cellular Cytotoxicity-Mediating Antibodies in a Rabbit Vaccination Model.

Science.gov (United States)

Karlsson, Ingrid; Borggren, Marie; Jensen, Sanne Skov; Heyndrickx, Leo; Stewart-Jones, Guillaume; Scarlatti, Gabriella; Fomsgaard, Anders

2017-11-17

The induction of both neutralizing antibodies and non-neutralizing antibodies with effector functions, for example, antibody-dependent cellular cytotoxicity (ADCC), is desired in the search for effective vaccines against HIV-1. In the pursuit of novel immunogens capable of inducing an efficient antibody response, rabbits were immunized with selected antigens using different prime-boost strategies. We immunized 35 different groups of rabbits with Env antigens from clinical HIV-1 subtypes A and B, including immunization with DNA alone, protein alone, and DNA prime with protein boost. The rabbit sera were screened for ADCC activity using a GranToxiLux-based assay with human peripheral blood mononuclear cells as effector cells and CEM.NKR CCR5 cells coated with HIV-1 envelope as target cells. The groups with the highest ADCC activity were further characterized for cross-reactivity between HIV-1 subtypes. The immunogen inducing the most potent and broadest ADCC response was a trimeric gp140. The ADCC activity was highest against the HIV-1 subtype corresponding to the immunogen. The ADCC activity did not necessarily reflect neutralizing activity in the pseudovirus-TZMbl assay, but there was an overall correlation between the two antiviral activities. We present a rabbit vaccination model and an assay suitable for screening HIV-1 vaccine candidates for the induction of ADCC-mediating antibodies in addition to neutralizing antibodies. The antigens and/or immunization strategies capable of inducing antibodies with ADCC activity did not necessarily induce neutralizing activity and vice versa. Nevertheless, we identified vaccine candidates that were able to concurrently induce both types of responses and that had ADCC activity that was cross-reactive between different subtypes. When searching for an effective vaccine candidate, it is important to evaluate the antibody response using a model and an assay measuring the desired function.

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

Directory of Open Access Journals (Sweden)

Gene S Tan

2016-04-01

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

Radioiodination of antibodies for tumor imaging

International Nuclear Information System (INIS)

Saha, G.B.

1983-01-01

In view of the great potential of radioiodinated antibody for the detection and treatment of cancer, the present article deals with the various techniques of radioiodination of antibody and their uses. Topics include methods of iodination of antibody, advantages and disadvantages of different methods, and effects of radioiodination on the antibody molecules with respect to their physiochemical and immunologic reactivity. In addition, the clinical usefulness of radioiodinated antibodies is discussed. (Auth.)

Plasma exchange to remove HIT antibodies: dissociation between enzyme-immunoassay and platelet activation test reactivities.

Science.gov (United States)

Warkentin, Theodore E; Sheppard, Jo-Ann I; Chu, F Victor; Kapoor, Anil; Crowther, Mark A; Gangji, Azim

2015-01-01

Repeated therapeutic plasma exchange (TPE) has been advocated to remove heparin-induced thrombocytopenia (HIT) IgG antibodies before cardiac/vascular surgery in patients who have serologically-confirmed acute or subacute HIT; for this situation, a negative platelet activation assay (eg, platelet serotonin-release assay [SRA]) has been recommended as the target serological end point to permit safe surgery. We compared reactivities in the SRA and an anti-PF4/heparin IgG-specific enzyme immunoassay (EIA), testing serial serum samples in a patient with recent (subacute) HIT who underwent serial TPE precardiac surgery, as well as for 15 other serially-diluted HIT sera. We observed that post-TPE/diluted HIT sera-when first testing SRA-negative-continue to test strongly positive by EIA-IgG. This dissociation between the platelet activation assay and a PF4-dependent immunoassay for HIT antibodies indicates that patients with subacute HIT undergoing repeated TPE before heparin reexposure should be tested by serial platelet activation assays even when their EIAs remain strongly positive. © 2015 by The American Society of Hematology.

Generation of memory B cells and their reactivation.

Science.gov (United States)

Inoue, Takeshi; Moran, Imogen; Shinnakasu, Ryo; Phan, Tri Giang; Kurosaki, Tomohiro

2018-05-01

The successful establishment of humoral memory response depends on at least two layers of defense. Pre-existing protective antibodies secreted by long-lived plasma cells act as a first line of defense against reinfection ("constitutive humoral memory"). Previously, a second line of defense in which pathogen-experienced memory B cells are rapidly reactivated to produce antibodies ("reactive humoral memory"), was considered as simply a back-up system for the first line (particularly for re-infection with homologous viruses). However, in the case of re-infection with similar but different strains of viruses, or in response to viral escape mutants, the reactive humoral memory plays a crucial role. Here, we review recent progress in our understanding of how memory B cells are generated in the pre-GC stage and during the GC reaction, and how these memory B cells are robustly reactivated with the help of memory Tfh cells to generate the secondary antibody response. In addition, we discuss how these advances may be relevant to the quest for a vaccine that can induce broadly reactive antibodies against influenza and HIV. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Radioimmunoassay with heterologous antibody (hetero-antibody RIA)

International Nuclear Information System (INIS)

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

1991-01-01

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

Antibodies reactive to Plasmodium falciparum serine repeat antigen in children with Burkitt lymphoma from Ghana.

Science.gov (United States)

Guech-Ongey, Mercy; Yagi, Masanori; Palacpac, Nirianne Marie Q; Emmanuel, Benjamin; Talisuna, Ambrose O; Bhatia, Kishor; Stefan, D Cristina; Biggar, Robert J; Nkrumah, Francis; Neequaye, Janet; Tougan, Takahiro; Horii, Toshihiro; Mbulaiteye, Sam M

2012-04-15

The role of protective immunity to Plasmodium falciparum (Pf) malaria in Burkitt lymphoma (BL) is unknown. We investigated the association between BL and antibodies reactive to SE36 antigen, a recombinant protein based on P. falciparum serine repeat antigen 5 gene, targeted by protective malaria immune responses. Cases were children (0-14 years) enrolled at the Korle-Bu Teaching Hospital, Accra, Ghana, during 1965-1994 with BL confirmed by histology or cytology (92% of cases). Controls were apparently healthy children enrolled contemporaneous to the cases from the nearest neighbor house to the case house and were age,- sex-frequency-matched to the cases. Anti-SE36 IgG antibodies were measured using enzyme-linked absorbent immunoassays (ELISAs). SE36 titers were estimated by extrapolating ELISA optical density readings to a standard fitting curve. Anti-SE36 titers were log-transformed for analysis. Odds ratios (ORs) and two-sided 95% confidence intervals (95% CIs) were estimated using unconditional logistic regression. The mean log endpoint dilution titers were 0.63 logs lower in cases than in controls (8.26 [SD 1.68] vs. 8.89 [SD 1.75], Student's t-test, p = 0.019). Lower titers were observed in cases than controls aged 0-4 years (p = 0.05) and in those aged 5-14 years (p = 0.06). Low and medium tertiles of anti-SE36 IgG antibodies were associated with increased OR for BL ([OR 1.67, 95% CI 1.21-2.31] and [OR 1.33, 95% CI 0.96-1.86], respectively, p(trend) = 0.002) in analyses adjusting for age, sex, calendar period and test plate. Our findings suggest that compared to similarly aged children enrolled from the same community, children with BL in Ghana have lower antibodies to SE36 antigen. Copyright © 2011 UICC.

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

Science.gov (United States)

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

2015-02-01

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

Engineered Antibodies for Monitoring of Polynuclear Aromatic Hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Alexander E. Karu Ph.D; Victoria A. Roberts Ph.D.; Qing X. Li, Ph.D.

2002-01-17

This project was undertaken to fill needs in ODE's human and ecosystem health effects research, site remediation, rapid emergency response, and regulatory compliance monitoring programs. Doe has greatly stimulated development and validation of antibody-based, rapid, field-portable detection systems for small hazardous compounds. These range from simple dipsticks, microplate enzyme-linked immunosorbent assays (ELISAs), and hand-held colorimeters, to ultrasensitive microfluidic reactors, fiber-optic sensors and microarrays that can identify multiple analytes from patterns of cross-reactivity. Unfortunately, the technology to produce antibodies with the most desirable properties did not keep pace. Lack of antibodies remains a limiting factor in production and practical use of such devices. The goals of our project were to determine the chemical and structural bases for the antibody-analyte binding interactions using advanced computational chemistry, and to use this information to create useful new binding properties through in vitro genetic engineering and combinatorial library methods.

Increased specificity in human cardiac-myosin radioimmunoassay utilizing two monoclonal antibodies in a double sandwich assay

International Nuclear Information System (INIS)

Katus, H.A.; Hurrell, J.G.; Matsueda, G.R.; Ehrlich, P.; Zurawski, V.R. Jr.; Khaw, B.-A.; Haber, E.

1982-01-01

An immunoradiometric assay that simultaneously measured two different epitopes on the same molecule was devised to differential between cardiac- and skeletal-myosin light chains. Three monoclonal antibodies were examined that were 100% (lC5), 25% (2B9) and 17% (4F10) cross reactive, respectively, between the two antigens. One antibody of the pair to be studied was immobilized to cyanogen bromide-activated Sepharose 4B while the other was iodinated with 125 I using the lactoperoxidase method. The antigen was mixed with the immobilized antibody, the labeled antibody was added and the precipitate then washed and counted in a gamma counter. When both antibodies of the pair to be studied (immobilized and labeled) were the same (2B9), no radioactivity above background was bound to the precipitate, indicating that the second antibody could not bind to an already occupied epitope. When two different antibodies were employed, the specificity of the assay increased over that of a single antibody. The cross reactivity of a pair approximated the product of the cross reactivities of the individual antibodies. Thus, lC5 and 2B9 were 25% cross reactive together, lC5 and 4F10 17% cross reactive, and 2B9 and 4F10 4.3% cross reactive. (author)

Panel reactive HLA antibodies, soluble CD30 levels, and acute rejection six months following renal transplant.

Science.gov (United States)

Domingues, Elizabeth M F L; Matuck, Teresa; Graciano, Miguel L; Souza, Edison; Rioja, Suzimar; Falci, Mônica C; Monteiro de Carvalho, Deise B; Porto, Luís Cristóvão

2010-01-01

Specific anti-human leukocyte antigen antibodies (HLA) in the post-transplant period may be present with acute rejection episodes (ARE), and high soluble CD30 (sCD30) serum levels may be a risk factor for ARE and graft loss. HLA cross-matching, panel reactive antibodies (PRA), and sCD30 levels were determined prior to transplantation in 72 patients. Soluble CD30 levels and PRA were re-assessed at day 7, 14, 21, and 28, and monthly up to the sixth.   Twenty-four subjects had a positive PRA and 17 experienced ARE. Nine of 17 ARE subjects demonstrated positive PRA and 16 had HLA mismatches. Positive PRA was more frequent in ARE subjects (p = 0.03). Eight subjects with ARE had donor-specific antibodies (DSA) in serum samples pre-transplantation, two subjects developed DSA. Three subjects without ARE had positive PRA only in post-transplantation samples. Soluble CD30 levels were higher in pre-transplant samples and ARE subjects than non-ARE subjects (p = 0.03). Post-transplant sCD30 levels were elevated in subjects who experienced rejection and were significantly higher at seven d (p = 0.0004) and six months (p = 0.03). Higher sCD30 levels following transplant were associated with ARE. Elevated sCD30 levels may represent a risk factor for acute rejection. © 2009 John Wiley & Sons A/S.

Soluble CD30 concentrations in ESRD patients with and without panel reactive HLA antibodies.

Science.gov (United States)

Vaidya, Smita; Partlow, David; Barnes, Titus; Thomas, Phillip; Gugliuzza, Kristin

2006-01-01

In this retrospective study we compared accuracy of panel reactive antibodies (PRA) with serum soluble CD30 (sCD30) contents in predicting acute rejection crisis post-renal transplant. Pre-transplant sera from 115 patients were evaluated for their PRA and sCD30 concentrations. All patients received calcineurin inhibitor-based immunosuppressive therapy. Objective measurements for rejection were biopsy-proven acute rejection (AR) episodes within first six months of the transplant. Post-transplant sera of patients with AR were tested for the presence of donor-specific HLA antibodies (DSA). Overall AR rate was 16% (18/115). Patients positive for PRA and sCD30 tests were at significantly higher risk for AVR compared with those patients negative for both the tests (36% vs. 5%, p=0.01). Among negative PRA patients risk for AR was significantly elevated if they were also tested positive for sCD30 concentrations (21% vs. 5%, p=0.04). Of the 18 patients with AR, 14 were positive for sCD30, and 13 of them (93%) developed DSA post-transplant (p=0.001). These data showed that patients positive for sCD30 contents are at high risk for the development of DSA and AR post-transplant regardless of their pre-transplant PRA.

[Antibody therapy for Alzheimer's disease].

Science.gov (United States)

Tabira, Takeshi; Matsumoto, Shin-Ei; Jin, Haifeng

2011-11-01

In order to avoid Abeta-induced autoimmune encephalitis, several monoclonal and polyclonal antibodies are in clinical trials. These are bapineuzumab, solanezumab, ponezumab, gantenerumab, BAN2401, gammaguard and octagam. Since each antibody has a different antigen epitope of Abeta, anti-amyloid activities are different. It is unknown which antibody is effective for Alzheimer disease, and we must wait for the result of clinical trials. Some patients who developed tissue amyloid plaque immuno-reactive (TAPIR) antibody showed slower decline after AN-1792 vaccination. We developed TAPIR-like monoclonal antibody, which was found to react with Abeta oligomers preferentially.

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

Energy Technology Data Exchange (ETDEWEB)

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

2002-06-14

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

Identification of anti-HPA-1a allo-antibodies using IgG platelet antibody detection and crossmatch system assay with Galileo Echo.

Science.gov (United States)

Di Cristofaro, Julie; Frassati, Coralie; Montagnie, Rolande; Basire, Agnes; Merieux, Yves; Picard, Christophe

2015-01-01

Fetal/neonatal allo-immune thrombocytopenia is the most frequent and the most dangerous clinical condition involving anti-human platelet antigens (HPA)-1a allo-antibodies. Anti-HPA-1a allo-immunization requires rapid and accurate diagnosis to determine appropriate treatment. The Capture-P Ready-Screen assay (C-PRS) is a new qualitative immunoassay to detect IgG anti-human leukocyte antigen (HLA) and anti-HPA allo-antibodies. The aim of this study is to assess the identification of anti-HPA-1a allo-antibodies using the C-PRS assay, associated with HLA class I stripping reagents, on the automated benchtop analyzer Galileo Echo. Forty-nine sera were analyzed: without anti-HLA class I or anti-HPA allo-antibodies, with anti-HLA class I allo-antibodies, with anti-HPA-1a allo-antibodies, among which with anti-HLA class I allo-antibodies. None of the samples without allo-antibodies were reactive. Only anti-HLA antibodies, detected by cytotoxicity-dependent complement and not by Luminex, remained positive before and after stripping reagents. Of the 13 samples, anti-HPA-1a allo-antibodies that were correctly identified before and after incubation with HLA assassin reagent were 70% and 85%, respectively. Anti-glycoprotein auto-antibodies and anti-HLA allo-antibodies do not interfere with the detection of anti-HPA-1a antibodies. This preliminary study indicates that further improvement of the test will be helpful in developing a clinically useful assay in the future.

Somatic populations of PGT135-137 HIV-1-neutralizing antibodies identified by 454 pyrosequencing and bioinformatics

Directory of Open Access Journals (Sweden)

Jiang eZhu

2012-09-01

Full Text Available Select HIV-1-infected individuals develop sera capable of neutralizing diverse viral strains. The molecular basis of this neutralization is currently being deciphered by the isolation of HIV-1-neutralizing antibodies. In one infected donor, three neutralizing antibodies, PGT135-137, were identified by assessment of neutralization from individually sorted B cells and found to recognize an epitope containing an N-linked glycan at residue 332 on HIV-1 gp120. Here we use deep sequencing and bioinformatics methods to interrogate the B cell record of this donor to gain a more complete understanding of the humoral immune response. PGT135-137-gene family-specific primers were used to amplify heavy and light chain-variable domain sequences. 454 pyrosequencing produced 141,298 heavy-chain sequences of IGHV4-39 origin and 87,229 light-chain sequences of IGKV3-15 origin. A number of heavy and light chain sequences of ~90% identity to PGT137, several to PGT136, and none of high identity to PGT135 were identified. After expansion of these sequences to include close phylogenetic relatives, a total of 202 heavy-chain sequences and 72 light-chain sequences were identified. These sequences were clustered into populations of 95% identity comprising 15 for heavy chain and 10 for light chain, and a select sequence from each population was synthesized and reconstituted with a PGT137-partner chain. Reconstituted antibodies showed varied neutralization phenotypes for HIV-1 clade A and D isolates. Sequence diversity of the antibody population represented by these tested sequences was notably higher than observed with a 454 pyrosequencing-control analysis on 10 antibodies of defined sequence, suggesting that this diversity results primarily from somatic maturation. Our results thus provide an example of how pathogens like HIV-1 are opposed by a varied humoral immune response, derived from intrinsic mechanisms of antibody development, and embodied by somatic populations

Genome-wide association study on the development of cross-reactive neutralizing antibodies in HIV-1 infected individuals.

Directory of Open Access Journals (Sweden)

Zelda Euler

Full Text Available Broadly neutralizing antibodies may protect against HIV-1 acquisition. In natural infection, only 10-30% of patients have cross-reactive neutralizing humoral immunity which may relate to viral and or host factors. To explore the role of host genetic markers in the formation of cross-reactive neutralizing activity (CrNA in HIV-1 infected individuals, we performed a genome-wide association study (GWAS, in participants of the Amsterdam Cohort Studies with known CrNA in their sera. Single-nucleotide polymorphisms (SNPs with the strongest P-values are located in the major histocompatibility complex (MHC region, close to MICA (P = 7.68 × 10(-7, HLA-B (P = 6.96 × 10(-6 and in the coding region of HCP5 (P = 1.34 × 10(-5. However, none of the signals reached genome-wide significance. Our findings underline the potential involvement of genes close or within the MHC region with the development of CrNA.

Genome-Wide Association Study on the Development of Cross-Reactive Neutralizing Antibodies in HIV-1 Infected Individuals

Science.gov (United States)

Euler, Zelda; van Gils, Marit J.; Boeser-Nunnink, Brigitte D.; Schuitemaker, Hanneke; van Manen, Daniëlle

2013-01-01

Broadly neutralizing antibodies may protect against HIV-1 acquisition. In natural infection, only 10–30% of patients have cross-reactive neutralizing humoral immunity which may relate to viral and or host factors. To explore the role of host genetic markers in the formation of cross-reactive neutralizing activity (CrNA) in HIV-1 infected individuals, we performed a genome-wide association study (GWAS), in participants of the Amsterdam Cohort Studies with known CrNA in their sera. Single-nucleotide polymorphisms (SNPs) with the strongest P-values are located in the major histocompatibility complex (MHC) region, close to MICA (P = 7.68×10−7), HLA-B (P = 6.96×10−6) and in the coding region of HCP5 (P = 1.34×10−5). However, none of the signals reached genome-wide significance. Our findings underline the potential involvement of genes close or within the MHC region with the development of CrNA. PMID:23372753

MONOCLONAL ANTIBODIES TO IDENTIFY TOMATO MOSAIC TOBAMOVIRUS (TOMV

Directory of Open Access Journals (Sweden)

Duarte Keila M.R.

2001-01-01

Full Text Available Monoclonal antibodies were obtained against Tomato mosaic tobamovirus (ToMV isolated in Brazil. One antibody (8G7G2 isotyped as IgG2b (kappa light chain showed strong specificity and very low cross reaction with the Tobacco mosaic virus (TMV. It can be used in identification of tomato mosaic virus (ToMV.

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

NARCIS (Netherlands)

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

1991-01-01

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

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

Science.gov (United States)

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

2004-01-01

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

Ankle brachial index, C-reactive protein, and central augmentation index to identify individuals with severe atherosclerosis

DEFF Research Database (Denmark)

Eldrup, Nikolaj; Sillesen, Henrik; Prescott, Eva

2006-01-01

We examined the ability of ankle brachial index, C-reactive protein and central augmentation index to identify individuals in the general population with severe atherosclerosis, diagnosed as those with ischaemic cardiovascular disease.......We examined the ability of ankle brachial index, C-reactive protein and central augmentation index to identify individuals in the general population with severe atherosclerosis, diagnosed as those with ischaemic cardiovascular disease....

Anti-G antibody in alloimmunized pregnant women: Report of two cases

Directory of Open Access Journals (Sweden)

Raj Nath Makroo

2015-01-01

Full Text Available Anti-G has been reported as a possible cause of hemolytic disease of the fetus and newborn (HDFN, either independently or in association with anti-D, anti-C or both. The antibody mimics the pattern of anti-C and anti-D reactivity in the identification panel and is often present along with either or both of these antibodies. The differentiation of anti-D, -C and-G in routine pretransfusion workup is particularly essential in antenatal cases. We report two antenatal cases where anti-G was identified on advanced immunohematological workup, in addition to other alloantibodies.

Treatment-responsive limbic encephalitis identified by neuropil antibodies: MRI and PET correlates

Science.gov (United States)

Ances, Beau M.; Vitaliani, Roberta; Taylor, Robert A.; Liebeskind, David S.; Voloschin, Alfredo; Houghton, David J.; Galetta, Steven L.; Dichter, Marc; Alavi, Abass; Rosenfeld, Myrna R.; Dalmau, Josep

2007-01-01

We report seven patients, six from a single institution, who developed subacute limbic encephalitis initially considered of uncertain aetiology. Four patients presented with symptoms of hippocampal dysfunction (i.e. severe short-term memory loss) and three with extensive limbic dysfunction (i.e. confusion, seizures and suspected psychosis). Brain MRI and [18F]fluorodeoxyglucose (FDG)-PET complemented each other but did not overlap in 50% of the patients. Combining both tests, all patients had temporal lobe abnormalities, five with additional areas involved. In one patient, FDG hyperactivity in the brainstem that was normal on MRI correlated with central hypoventilation; in another case, hyperactivity in the cerebellum anticipated ataxia. All patients had abnormal CSF: six pleocytosis, six had increased protein concentration, and three of five examined had oligoclonal bands. A tumour was identified and removed in four patients (mediastinal teratoma, thymoma, thymic carcinoma and thyroid cancer) and not treated in one (ovarian teratoma). An immunohistochemical technique that facilitates the detection of antibodies to cell surface or synaptic proteins demonstrated that six patients had antibodies to the neuropil of hippocampus or cerebellum, and one to intraneuronal antigens. Only one of the neuropil antibodies corresponded to voltage-gated potassium channel (VGKC) antibodies; the other five (two with identical specificity) reacted with antigens concentrated in areas of high dendritic density or synaptic-enriched regions of the hippocampus or cerebellum. Preliminary characterization of these antigens indicates that they are diverse and expressed on the neuronal cell membrane and dendrites; they do not co-localize with VGKCs, but partially co-localize with spinophilin. A target autoantigen in one of the patients co-localizes with a cell surface protein involved in hippocampal dendritic development. All patients except the one with antibodies to intracellular antigens

Immunological cross-reactivity between four distant parvalbumins-Impact on allergen detection and diagnostics.

Science.gov (United States)

Sharp, Michael F; Stephen, Juan N; Kraft, Lukas; Weiss, Thomas; Kamath, Sandip D; Lopata, Andreas L

2015-02-01

Fish are the largest and most diverse group of vertebrates. Fish are also a part of the eight food groups that cause the majority of IgE mediated food reactions. Detection tools for fish allergens are however limited due to the great diversity of fish species, despite fish allergy and its major allergen parvalbumin being well documented. The most commonly studied fish are frequently consumed in North America and Europe. However, much less is known about fish allergens in the Australasian region although fish is widely consumed in this region. A comprehensive phylogenetic analysis was performed of known parvalbumin amino acid sequences to determine possible candidate antigens for new cross-reactive antibodies to be used to detect most fish parvalbumins. Polyclonal rabbit antibodies were raised against parvalbumins from frequently consumed barramundi (Lates calcarifer), basa (Pangasius bocourti), pilchard (Sardinops sagax) and Atlantic salmon (Salmo salar). These were evaluated for cross-reactivity against a panel of 45 fish extracts (raw, heated and canned fish). Anti-barramundi parvalbumin proved to be the most cross-reactive antibody, detecting 87.5% of the 40 species analyzed, followed by anti-pilchard and anti-basa antibody. In contrast the anti-salmon antibody was very specific and only reacted to salmonidae and a few other fish. All analyzed fish species, except mahi mahi, swordfish, yellowfin tuna and all 5 canned fish had parvalbumin detected in raw extracts. However antibody reactivity to many fish was heat liable or susceptible to denaturation, demonstrating that some parvalbumins have most likely conformational epitopes, which lose antibody reactivity after heat treatment. We have demonstrated the generation of highly cross-reactive anti-parvalbumin antibodies that could be used for the detection of allergenic fish parvalbumin in contaminated food products. This cross-reactivity study thus shows processing of fish, especially canning, can have on impact

Induction of homologous and cross-reactive GII.4-specific blocking antibodies in children after GII.4 New Orleans norovirus infection.

Science.gov (United States)

Blazevic, Vesna; Malm, Maria; Vesikari, Timo

2015-10-01

Noroviruses (NoVs) are major causative agents of acute gastroenteritis (AGE) in children worldwide and the most common viral cause of AGE in countries where rotavirus incidence has been eliminated by vaccination. Previous infections with the dominant GII.4 NoV genotype confer only partial protection against evolving immune escape variants that emerge every few years. The objective of this work was to investigate GII.4-specific homologous and cross-reactive antibody responses in young children after NoV GII.4-2009 New Orleans (NO) infection. Virus-like particles (VLPs) representing GII.4-1999, GII.4-2009 NO, and GII.4-2012 Sydney genotypes were used in ELISA and histo-blood group antigen blocking assays to examine acute and convalescent sera of five children <2 years of age infected with GII.4-2009 NO. GII.4-2009 NO infection induced IgG seroconversion to all three tested NoV GII.4 variants. Homologous blocking antibodies to GII.4-2009 NO were detected in each convalescent sera. Fourfold increase in cross-blocking antibodies to GII.4-2012 Sydney was observed in 4/5 subjects, but no child developed cross-blocking antibodies to GII.4-1999. In conclusion, antibodies induced in young children after norovirus GII.4 infection are targeted against the causative variant and may cross-protect against strains that are closely related, but not with more distinct and earlier GII.4 genotypes. © 2015 Wiley Periodicals, Inc.

Verification of the Cross Immunoreactivity of A60, a Mouse Monoclonal Antibody against Neuronal Nuclear Protein.

Science.gov (United States)

Mao, Shanping; Xiong, Guoxiang; Zhang, Lei; Dong, Huimin; Liu, Baohui; Cohen, Noam A; Cohen, Akiva S

2016-01-01

A60, the mouse monoclonal antibody against the neuronal nuclear protein (NeuN), is the most widely used neuronal marker in neuroscience research and neuropathological assays. Previous studies identified fragments of A60-immunoprecipitated protein as Synapsin I (Syn I), suggesting the antibody will demonstrate cross immunoreactivity. However, the likelihood of cross reactivity has never been verified by immunohistochemical techniques. Using our established tissue processing and immunofluorescent staining protocols, we found that A60 consistently labeled mossy fiber terminals in hippocampal area CA3. These A60-positive mossy fiber terminals could also be labeled by Syn I antibody. After treating brain slices with saponin in order to better preserve various membrane and/or vesicular proteins for immunostaining, we observed that A60 could also label additional synapses in various brain areas. Therefore, we used A60 together with a rabbit monoclonal NeuN antibody to confirm the existence of this cross reactivity. We showed that the putative band positive for A60 and Syn I could not be detected by the rabbit anti-NeuN in Western blotting. As efficient as Millipore A60 to recognize neuronal nuclei, the rabbit NeuN antibody demonstrated no labeling of synaptic structures in immunofluorescent staining. The present study successfully verified the cross reactivity present in immunohistochemistry, cautioning that A60 may not be the ideal biomarker to verify neuronal identity due to its cross immunoreactivity. In contrast, the rabbit monoclonal NeuN antibody used in this study may be a better candidate to substitute for A60.

Sequence homology: A poor predictive value for profilins cross-reactivity

Directory of Open Access Journals (Sweden)

Pazouki Nazanin

2005-09-01

Full Text Available Summary Background Profilins are highly cross-reactive allergens which bind IgE antibodies of almost 20% of plant-allergic patients. This study is aimed at investigating cross-reactivity of melon profilin with other plant profilins and the role of the linear and conformational epitopes in human IgE cross-reactivity. Methods Seventeen patients with melon allergy were selected based on clinical history and a positive skin prick test to melon extract. Melon profilin has been cloned and expressed in E. coli. The IgE binding and cross-reactivity of the recombinant profilin were measured by ELISA and inhibition ELISA. The amino acid sequence of melon profilin was compared with other profilin sequences. A combination of chemical cleavage and immunoblotting techniques were used to define the role of conformational and linear epitopes in IgE binding. Comparative modeling was used to construct three-dimensional models of profilins and to assess theoretical impact of amino acid differences on conformational structure. Results Profilin was identified as a major IgE-binding component of melon. Alignment of amino acid sequences of melon profilin with other profilins showed the most identity with watermelon profilin. This melon profilin showed substantial cross-reactivity with the tomato, peach, grape and Cynodon dactylon (Bermuda grass pollen profilins. Cantaloupe, watermelon, banana and Poa pratensis (Kentucky blue grass displayed no notable inhibition. Our experiments also indicated human IgE only react with complete melon profilin. Immunoblotting analysis with rabbit polyclonal antibody shows the reaction of the antibody to the fragmented and complete melon profilin. Although, the well-known linear epitope of profilins were identical in melon and watermelon, comparison of three-dimensional models of watermelon and melon profilins indicated amino acid differences influence the electric potential and accessibility of the solvent-accessible surface of

Antibody proteases: induction of catalytic response.

Science.gov (United States)

Gabibov, A G; Friboulet, A; Thomas, D; Demin, A V; Ponomarenko, N A; Vorobiev, I I; Pillet, D; Paon, M; Alexandrova, E S; Telegin, G B; Reshetnyak, A V; Grigorieva, O V; Gnuchev, N V; Malishkin, K A; Genkin, D D

2002-10-01

Most of the data accumulated throughout the years on investigation of catalytic antibodies indicate that their production increases on the background of autoimmune abnormalities. The different approaches to induction of catalytic response toward recombinant gp120 HIV-1 surface protein in mice with various autoimmune pathologies are described. The peptidylphosphonate conjugate containing structural part of gp120 molecule is used for reactive immunization of NZB/NZW F1, MRL, and SJL mice. The specific modification of heavy and light chains of mouse autoantibodies with Val-Ala-Glu-Glu-Glu-Val-PO(OPh)2 reactive peptide was demonstrated. Increased proteolytic activity of polyclonal antibodies in SJL mice encouraged us to investigate the production of antigen-specific catalytic antibodies on the background of induced experimental autoimmune encephalomyelitis (EAE). The immunization of autoimmune-prone mice with the engineered fusions containing the fragments of gp120 and encephalitogenic epitope of myelin basic protein (MBP(89-104)) was made. The proteolytic activity of polyclonal antibodies isolated from the sera of autoimmune mice immunized by the described antigen was shown. Specific immune response of SJL mice to these antigens was characterized. Polyclonal antibodies purified from sera of the immunized animals revealed proteolytic activity. The antiidiotypic approach to raise the specific proteolytic antibody as an "internal image" of protease is described. The "second order" monoclonal antibodies toward subtilisin Carlsberg revealed pronounced proteolytic activity.

[Current Perspective on Voltage-gated Potassium Channel Complex Antibody Associated Diseases].

Science.gov (United States)

Watanabe, Osamu

2018-04-01

Voltage-gated potassium channel (VGKC) complex auto-antibodies were initially identified in Isaacs' syndrome (IS), which is characterized by muscle cramps and neuromyotonia. These antibodies were subsequently identified in patients with Morvan's syndrome (MoS), which includes IS in conjunction with psychosis, insomnia, and dysautonomia. The antibodies have also been detected in a patient with limbic encephalopathy (LE) presenting with prominent amnesia and frequent seizures. Typical cases of LE have adult-onset, with frequent, brief dystonic seizures that predominantly affect the arms and ipsilateral face, and has recently been termed faciobrachial dystonic seizures. Autoantibodies against the extracellular domains of VGKC complex proteins, leucine-rich glioma-inactivated 1 (LGI1), and contactin-associated protein-2 (Caspr2), occur in patients with IS, MoS, and LE. However, routine testing has detected VGKC complex antibodies without LGI1 or Caspr2 reactivities (double-negative) in patients with other diseases, such as Creutzfeldt-Jakob disease and amyotrophic lateral sclerosis. Furthermore, double-negative VGKC complex antibodies are often directed against cytosolic epitopes of Kv1 subunits. Therefore, these antibodies should no longer be classified as neuronal-surface antibodies and lacking pathogenic potential. Novel information has been generated regarding autoantibody disruption of the physiological functions of target proteins. LGI1 antibodies neutralize the interaction between LGI1 and ADAM22, thereby reducing the synaptic AMPA receptors. It may be that the main action is on inhibitory neurons, explaining why the loss of AMPA receptors causes amnesia, neuronal excitability and seizures.

Development of broad-spectrum human monoclonal antibodies for rabies post-exposure prophylaxis

International Nuclear Information System (INIS)

Benedictis, P. de; Minola, A.; Rota, E.; Aiello, R.; Zecchin, B.; Salomoni, A.; Foglierini, M.; Agatic, G.; Vanzetta, F.; Lavenir, R.; Lepelletier, A.; Bentley, E.; Weiss, R.; Cattoli, G.

2016-01-01

Full text: Currently available rabies post-exposure prophylaxis (PEP) for use in humans includes equine or human rabies immunoglobulins (RIG). The replacement of RIG with an equally or more potent and safer product is strongly encouraged due to the high costs and limited availability of existing RIG. In this study, we identified two broadly neutralizing human monoclonal antibodies that represent a valid and affordable alternative to RIG in rabies PEP. Memory B cells from four selected vaccinated donors were immortalized and monoclonal antibodies were tested for neutralizing activity and epitope specificity. Two antibodies, identified as RVC20 and RVC58 (binding to antigenic site I and III, respectively), were selected for their potency and broad-spectrum reactivity. In vitro, RVC20 and RVC58 were able to neutralize all 35 rabies virus (RABV) and 25 non-RABV lyssaviruses. They showed higher potency and breath compared to antibodies under clinical development (namely CR57, CR4098, and RAB1) and commercially available human RIG. In vivo, the RVC20–RVC58 cocktail protected Syrian hamsters from a lethal RABV challenge and did not affect the endogenous hamster post-vaccination antibody response. (author)

Recent Advances in Monoclonal Antibody Therapies for Multiple Sclerosis

Science.gov (United States)

Stavropoulos, Nikolaos; Wittenberg, Nathan J.; Dasari, Harika; Abdelrahim, Murtada A.; Henley, John R.; Oh, Sang-Hyun; Warrington, Arthur E.; Rodriguez, Moses

2016-01-01

Introduction Multiple sclerosis (MS) is the most common chronic inflammatory, demyelinating disease of the CNS and results in neurological disability. Existing immunomodulatory and immunosuppressive approaches lower the number of relapses but do not cure or reverse existing deficits nor improve long-term disability in MS patients. Areas Covered Monogenic antibodies were described as treatment options for MS, however the immunogenicity of mouse antibodies hampered the efficacy of potential therapeutics in humans. Availability of improved antibody production technologies resulted in a paradigm shift in MS treatment strategies. In this review, an overview of immunotherapies for MS that use conventional monoclonal antibodies reactive to immune system and their properties and mechanisms of action will be discussed, including recent advances in MS therapeutics and highlight natural autoantibodies (NAbs) that directly target CNS cells. Expert Opinion Recent challenges for MS therapy are the identification of relevant molecular and cellular targets, time frame of treatment, and antibody toxicity profiles to identify safe treatment options for MS patients. The application of monoclonal antibody therapies with better biological efficacy associated with minimum side effects possesses huge clinical potential. Advances in monoclonal antibody technologies that directly target cells of nervous system may promote the CNS regeneration field from bench to bedside. PMID:26914737

Mammalian tissue distribution of a large heparan sulfate proteoglycan detected by monoclonal antibodies

DEFF Research Database (Denmark)

Couchman, J R; Ljubimov, A V

1989-01-01

muscle, endothelia, peripheral nerve fibers and epithelia so far examined. In addition, two of the monoclonal antibodies show cross-species reactivity, staining bovine and human basement membranes, and immunoprecipitating proteoglycans from human endothelial cell cultures. These antibodies do not......A panel of nine monoclonal antibodies has been characterized, all of which have reactivity with the core protein of a large heparan sulfate proteoglycan derived from the murine EHS tumor matrix. These rat monoclonal antibodies stained mouse basement membranes intensely, including those of all...

Detection of Islet Cell Immune Reactivity with Low Glycemic Index Foods: Is This a Concern for Type 1 Diabetes?

Directory of Open Access Journals (Sweden)

Datis Kharrazian

2017-01-01

Full Text Available Dietary management of autoimmune diabetes includes low glycemic foods classified from the glycemic index, but it does not consider the role that immunoreactive foods may play with the immunological etiology of the disease. We measured the reactivity of either monoclonal or polyclonal affinity-purified antibodies to insulin, insulin receptor alpha, insulin receptor beta, zinc transporter 8 (ZnT8, tyrosine phosphatase-based islet antigen 2 (IA2, and glutamic acid decarboxylase (GAD 65 and 67 against 204 dietary proteins that are commonly consumed. Dietary protein determinants included unmodified (raw and modified (cooked and roasted foods, herbs, spices, food gums, brewed beverages, and additives. There was no immune reactivity between insulin or insulin receptor beta and dietary proteins. However, we identified strong to moderate immunological reactivity with antibodies against insulin receptor alpha, ZnT8, IA2, GAD-65, and GAD-67 with several dietary proteins. We also identified 49 dietary proteins found in foods classified as low glycemic foods with immune reactivity to autoimmune target sites. Laboratory analysis of immunological cross-reactivity between pancreas target sites and dietary proteins is the initial step necessary in determining whether dietary proteins may play a potential immunoreactive role in autoimmune diabetes.

Antibody recognition of Z-DNA

International Nuclear Information System (INIS)

Lafer, E.M.; Moeller, A.; Valle, R.P.C.; Nordheim, V.A.; Rich, A.; Stollar, B.D.; Massachusetts Inst. of Tech., Cambridge)

1983-01-01

To measure serological reactions under physiological ionic strength, we prepared a brominated (Bl) poly(dG-dC).poly(dG-dC), which forms a stable Z helix in solutions of low salt concentration. Mice and rabbits were immunized with this polymer complexed with the basic protein methylated bovine serum albumin (MBSA), and it was discovered that the Z-DNA helix is a strong immunogen. Various antibody populations were purified from the rabbit serum by quantitative immunoprecipitation. Spleen cells from the mice were used for the preparation of hybridoma cell lines secreting monoclonal antibodies. Anti-Z-DNA antibodies were also raised by immunizing animals with poly(dG-dm 5 C).poly(dG-dm 5 C) under conditions where it was reported to be in the left-handed Z conformation as well as unmodified poly(dG-dC).poly(dG-dC) that was in the right-handed B conformation: both were complexed with MBSA. Z-DNA reactive antibodies were found in both murine and human SLE. A Z-DNA-specific as well as a dDNA and Z-DNA cross-reactive antibody population were distinguished by affinity chromatography of the SLE sera. The specificities of the various anti-Z-DNA antibody populations were measured by direct-binding and competitive radioimmunoassays, using synthetic polymers of defined structure under various ionic strengths. These studies allow us to map the possible antigenic sites for these antibodies, which serve as a model for DNA-protein recognition. The findings also established the usefulness of the antibodies as biochemical probes for Z-DNA. 29 references, 6 figures, 1 table

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

Science.gov (United States)

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

2017-05-01

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

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

Science.gov (United States)

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

2016-01-01

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

Application of synthetic peptides for detection of anti-citrullinated peptide antibodies

DEFF Research Database (Denmark)

Trier, Nicole Hartwig; Holm, Bettina Eide; Slot, Ole

2016-01-01

Anti-citrullinated protein antibodies (ACPAs) are a hallmark of rheumatoid arthritis (RA) and represent an important tool for the serological diagnosis of RA. In this study, we describe ACPA reactivity to overlapping citrullinated Epstein-Barr virus nuclear antigen-1 (EBNA-1)-derived peptides...... (n=40), systemic lupus erythematosus (n=20), Sjögren's syndrome (n=40)) were screened for antibody reactivity. Antibodies to a panel of five citrullinated EBNA-1 peptides were found in 67% of RA sera, exclusively of the IgG isotype, while 53% of the patient sera reacted with a single peptide......, ARGGSRERARGRGRG-Cit-GEKR, accounting for more than half of the ACPA reactivity alone. Moreover, these antibodies were detected in 10% of CCP2-negative RA sera. In addition, 47% of the RA sera reacted with two or three citrullinated EBNA-1 peptides from the selected peptide panel. Furthermore, a negative...

Cross-Reactivity of Polyclonal Antibodies against Canavalia ensiformis (Jack Bean) Urease and Helicobacter pylori Urease Subunit A Fragments.

Science.gov (United States)

Kaminski, Zbigniew Jerzy; Relich, Inga; Konieczna, Iwona; Kaca, Wieslaw; Kolesinska, Beata

2018-01-01

Overlapping decapeptide fragments of H. pylori urease subunit A (UreA) were synthesized and tested with polyclonal antibodies against Canavalia ensiformis (Jack bean) urease. The linear epitopes of UreA identified using the dot blot method were then examined using epitope mapping. For this purpose, series of overlapping fragments of UreA, frameshifted ± four amino acid residues were synthesized. Most of the UreA epitopes which reacted with the Jack bean urease polyclonal antibodies had been recognized in previous studies by monoclonal antibodies against H. pylori urease. Fragments 11 - 24, 21 - 33, and 31 - 42 were able to interact with the Jack bean urease antibodies, giving stable immunological complexes. However, the lack of recognition by these antibodies of all the components in the peptide map strongly suggests that a non-continuous (nonlinear) epitope is located on the N-terminal domain of UreA. © 2018 Wiley-VHCA AG, Zurich, Switzerland.

A radiolabeled antiglobulin assay to identify human cervical mucus immunoglobulin (Ig) A and IgG antisperm antibodies

International Nuclear Information System (INIS)

Haas, G.G. Jr.; D'Cruz, O.J.

1989-01-01

Antisperm immunoglobulin (Ig) A and IgG antibodies in human cervical mucus (CM) were identified by a radiolabeled antiglobulin assay. Cervical mucus samples from fertile and infertile women were exposed to a 1:3,200 dilution of 2-mercaptoethanol (2-ME), and 5 micrograms of the solubilized CM protein were assayed for the presence of IgA and IgG antisperm and anti-Candida activity by the radiolabeled antiglobulin assay. Purified human secretory IgA and IgG exposed to 2-ME retained the molecular integrity and functional activity of the untreated antibody molecules. CM aliquots collected after high-performance liquid chromatography (HPLC) fractionation were assessed for antisperm antibody activity; antisperm antibody activity was retained in the appropriate IgA or IgG CM fractions. The incidence of CM antisperm antibodies was minimally affected when the radiolabeled antiglobulin assay was performed with a motile sperm population. Approximately 70% of the CM IgA antisperm antibodies were of the IgA1 subclass; CM IgG was primarily of the IgG4 subclass. When Candida antigen was substituted for sperm in the radiolabeled antiglobulin assay, the CM antisperm antibodies were found to be exclusively sperm-specific. These data indicate that the radiolabeled antiglobulin assay using 2-ME to extract CM antibodies is a specific method for the assay of antisperm antibodies in CM

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

Directory of Open Access Journals (Sweden)

Encheng Sun

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

Antiphosphatidylserine/prothrombin antibodies as biomarkers to identify severe primary antiphospholipid syndrome.

Science.gov (United States)

Hoxha, Ariela; Mattia, Elena; Tonello, Marta; Grava, Chiara; Pengo, Vittorio; Ruffatti, Amelia

2017-05-01

Anti-phosphatidylserine/prothrombin (aPS/PT) antibodies have begun to be considered potentional biomarkers for antiphospholipid syndrome (APS). This cohort study investigate the role of aPS/PT antibodies as a risk factor for severe APS by evaluating the association between those antibodies and clinical/laboratory profiles of APS. Plasma/serum samples from 197 APS patients, 100 healthy subjects and 106 patients with autoimmune diseases were collected. IgG/IgM aPS/PT antibodies were assayed using commercial ELISA kit. Prevalences of IgG and IgM aPS/PT (pantiphospholipid antibody patients than in double and single positivity ones (p<0.0001 for all). APS/PT antibodies were associated to severe thrombosis, severe pregnancy complications inducing prematurity, and vascular microangiopathy, all generally associated to high risk APS forms requiring strong therapy.

Synthetic B-Cell Epitopes Eliciting Cross-Neutralizing Antibodies: Strategies for Future Dengue Vaccine.

Directory of Open Access Journals (Sweden)

Babu Ramanathan

Full Text Available Dengue virus (DENV is a major public health threat worldwide. A key element in protection from dengue fever is the neutralising antibody response. Anti-dengue IgG purified from DENV-2 infected human sera showed reactivity against several peptides when evaluated by ELISA and epitope extraction techniques. A multi-step computational approach predicted six antigenic regions within the E protein of DENV-2 that concur with the 6 epitopes identified by the combined ELISA and epitope extraction approach. The selected peptides representing B-cell epitopes were attached to a known dengue T-helper epitope and evaluated for their vaccine potency. Immunization of mice revealed two novel synthetic vaccine constructs that elicited good humoral immune responses and produced cross-reactive neutralising antibodies against DENV-1, 2 and 3. The findings indicate new directions for epitope mapping and contribute towards the future development of multi-epitope based synthetic peptide vaccine.

Elevated Subclinical Double-Stranded DNA Antibodies and Future Proliferative Lupus Nephritis

Science.gov (United States)

Lee, Jessica J.; Prince, Lisa K.; Baker, Thomas P.; Papadopoulos, Patricia; Edison, Jess; Abbott, Kevin C.

2013-01-01

Summary Background and objectives Elevated anti–double-stranded DNA (dsDNA) antibody and C-reactive protein are associated with proliferative lupus nephritis (PLN). Progression of quantitative anti-dsDNA antibody in patients with PLN has not been compared with that in patients with systemic lupus erythematosus (SLE) without LN before diagnosis. The temporal relationship between anti-dsDNA antibody and C-reactive protein elevation has also not been evaluated. Design, setting, participants, & measurements This case-control Department of Defense Serum Repository (established in 1985) study compared longitudinal prediagnostic quantitative anti-dsDNA antibody and C-reactive protein levels in 23 patients with biopsy-proven PLN (Walter Reed Army Medical Center, 1993–2009) with levels in 21 controls with SLE but without LN matched for patient age, sex, race, and age of serum sample. The oldest (median, 2601 days; 25%, 1245 days, 75%, 3075 days), the second to last (368; 212, 635 days), and the last (180; 135, 477 days) serum sample before diagnosis were analyzed. Results More patients with PLN had an elevated anti-dsDNA antibody level than did the matched controls at any point (78% versus 5%; P4 years (33% versus 0%; P=0.04) before diagnosis. A rate of increase >1 IU/ml per year (70% versus 0%; P<0.001) was most specific for PLN. The anti-dsDNA antibody levels increased before C-reactive protein did in most patients with an antecedent elevation (92% versus 8%; P<0.001). Conclusions Elevated anti-dsDNA antibody usually precedes both clinical and subclinical evidence of proliferative LN, which suggests direct pathogenicity. Absolute anti-dsDNA antibody level and rate of increase could better establish risk of future PLN in patients with SLE. PMID:23833315

Aqueous two-phase system patterning of detection antibody solutions for cross-reaction-free multiplex ELISA

Science.gov (United States)

Frampton, John P.; White, Joshua B.; Simon, Arlyne B.; Tsuei, Michael; Paczesny, Sophie; Takayama, Shuichi

2014-05-01

Accurate disease diagnosis, patient stratification and biomarker validation require the analysis of multiple biomarkers. This paper describes cross-reactivity-free multiplexing of enzyme-linked immunosorbent assays (ELISAs) using aqueous two-phase systems (ATPSs) to confine detection antibodies at specific locations in fully aqueous environments. Antibody cross-reactions are eliminated because the detection antibody solutions are co-localized only to corresponding surface-immobilized capture antibody spots. This multiplexing technique is validated using plasma samples from allogeneic bone marrow recipients. Patients with acute graft versus host disease (GVHD), a common and serious condition associated with allogeneic bone marrow transplantation, display higher mean concentrations for four multiplexed biomarkers (HGF, elafin, ST2 and TNFR1) relative to healthy donors and transplant patients without GVHD. The antibody co-localization capability of this technology is particularly useful when using inherently cross-reactive reagents such as polyclonal antibodies, although monoclonal antibody cross-reactivity can also be reduced. Because ATPS-ELISA adapts readily available antibody reagents, plate materials and detection instruments, it should be easily transferable into other research and clinical settings.

Monoclonal antibodies to the reactive centre loop (RCL) of human corticosteroid-binding globulin (CBG) can protect against proteolytic cleavage.

Science.gov (United States)

Lewis, John G; Elder, Peter A

2017-07-01

Corticosteroid-binding globulin (CBG) binds most of the cortisol in circulation and is a non-functional member of the family of serine protease inhibitors (serpins) with an exposed elastase sensitive reactive centre loop (RCL). The RCL can be cleaved by human neutrophil elastase, released from activated neutrophils, and can also be cleaved at nearby site(s) by elastase released by Pseudomonas aeruginosa, and at two further sites, also within the RCL, by bovine chymotrypsin. Cleavage of the RCL results in a conformational change accompanied by a marked decrease in affinity for cortisol and hence its release at the site of proteolysis. These cleavages are irreversible and the similar half-lives of cleaved and intact CBG could mean that there may be some advantage in slowing the rate of CBG cleavage in acute inflammation thereby increasing the proportion of intact CBG in circulation. Here we show, for the first time, that pre-incubation of tethered human CBG with two monoclonal antibodies to the RCL of CBG protects against cleavage by all three enzymes. Furthermore, in plasma, pre-incubation with both RCL monoclonal antibodies delays neutrophil elastase cleavage of the RCL and one of these RCL monoclonal antibodies also delays bovine chymotrypsin cleavage of the RCL. These findings may provide a basis and rationale for the concept of the use of RCL antibodies as therapeutic agents to effectively increase the proportion of intact CBG in circulation which may be of benefit in acute inflammation. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

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

2008-12-01

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

Anti-p-benzoquinone antibody level as a prospective biomarker to identify smokers at risk for COPD

Directory of Open Access Journals (Sweden)

Banerjee S

2017-06-01

.935 for identifying smokers with COPD from their low antibody level. The antibody cutoff value of 29.4 mg/dL was constructed from the ROC coordinates to estimate the risk for COPD in smokers. While 90.3% of smokers with COPD had a low antibody value (≤29.4 mg/dL, the majority (86.4% of smokers without COPD had a high antibody value (>29.4 mg/dL; 13.6% of current smokers without COPD having an antibody level below this cutoff value (odds ratio [OR] =59.3, 95% CI: 34.15–101.99 were considered to be at risk for COPD.Conclusion and future directions: Our results indicate that serum anti-p-BQ antibody level may be used as a biomarker to identify asymptomatic smokers at risk for COPD for early intervention of the disease. Keywords: COPD, cigarette smoke, biomarker, anti-p-benzoquinone antibody, enzyme-linked immunosorbent assay (ELISA 

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

Science.gov (United States)

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

2016-08-08

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

Immunological cross-reactivity to multiple autoantigens in patients with liver kidney microsomal type 1 autoimmune hepatitis.

Science.gov (United States)

Choudhuri, K; Gregorio, G V; Mieli-Vergani, G; Vergani, D

1998-11-01

We describe two patients with liver kidney microsomal antibody type 1 (LKM1)-positive autoimmune hepatitis (AIH) with associated endocrinopathies. The first patient had insulin-dependent diabetes (IDDM), and the second patient had Addison's disease and hypoparathyroidism, and is also positive for islet cell antibodies, without overt diabetes. To account for the existence of multiple endocrinopathy in these patients, we investigated whether there is sequence similarity between the target of LKM1 antibodies, cytochrome P4502D6 (CYP2D6), and other human proteins, and if so, whether this structural similarity produces a detectable cross-reactive immune response. Our database search identified two proteins, carboxypeptidase H, an autoantigen in insulin-dependent diabetes, and 21-hydroxylase, the major autoantigen in Addison's disease, that share sequence similarity to the second major LKM1 epitope on CYP2D6. We tested the reactivity of sera from these patients to the homologous regions of the three autoantigens using an enzyme-linked immunosorbent assay (ELISA). The cut-off for positivity was established by testing sera from 22 healthy children. To determine the significance of reactivity to the peptide homologues of the three autoantigens, we investigated 16 additional patients with LKM1 AIH and 20 children with chronic hepatitis B virus infection as pathological controls. We found that reactivity to the second major epitope of CYP2D6 is significantly associated with reactivity to the homologous regions of carboxypeptidase H (CPH) and 21-hydroxylase (21-OHase) in patients with LKM1 AIH, and that this simultaneous recognition is cross-reactive. We suggest that a cross-reactive immune response between homologous autoantigens may contribute to the development of multiple endocrinopathies in LKM1 AIH.

HLA-A2 reactive antibodies in a patient who types as HLA-A2: The importance of high resolution typing and epitope-based antibody analysis.

Science.gov (United States)

Hahn, A B; Bravo-Egana, V; Jackstadt, J L; Conti, D J; Duquesnoy, R J

2015-06-01

This report describes a case of a highly sensitized patient who had serum antibodies reacting with HLA-A2 but whose phenotype included HLA-A2. The determination of HLA mismatch acceptability at the antigen level was problematic, but high-resolution HLA typing information and epitope-based antibody specificity analysis based on the nonself-self paradigm of HLA epitope immunogenicity have provided a solution. This case supports the concept that HLA typing at the allele level offers a better approach to identifying suitable donors for sensitized patients. Copyright © 2015 Elsevier B.V. All rights reserved.

Characterisation of monoclonal antibodies for human luteinising hormone, and mapping of antigenic determinants on the hormone

International Nuclear Information System (INIS)

Soos, M.; Siddle, K.

1983-01-01

Twelve mouse monoclonal antibodies for human luteinising hormone were produced. The affinities varied from 4 X 10 7 to 1 X 10 10 l/mol. The specificity of each antibody was assessed by determining the relative reactivities with luteinising hormone, thyroid stimulating hormone, follicle stimulating hormone and chorionic gonadotrophin. Six antibodies bound to the α-subunit as shown by similar reactivity with all hormones, and the remainder to the β-subunit as shown by specificity for luteinising hormone. This latter group of antibodies cross-reacted only weakly with thyroid stimulating hormone (approximately 10%) and follicle stimulating hormone (approximately 3%). Three of these antibodies also showed low reactivity towards chorionic gonadotrophin (<10%), though the others did not (80-300%). The ability of different antibodies to bind simultaneously to luteinising hormone was examined and it was shown that several distinct antigenic determinants existed on both subunits. The characterisation of monoclonal binding sites is discussed in relation to the use of antibodies in two-site immunoradiometric assays. (Auth.)

Ghrelin-reactive immunoglobulins and anxiety, depression and stress-induced cortisol response in adolescents. The TRAILS study.

Science.gov (United States)

François, Marie; Schaefer, Johanna M; Bole-Feysot, Christine; Déchelotte, Pierre; Verhulst, Frank C; Fetissov, Sergueï O

2015-06-03

Ghrelin, a hunger hormone, has been implicated in the regulation of stress-response, anxiety and depression. Ghrelin-reactive immunoglobulins (Ig) were recently identified in healthy and obese humans showing abilities to increase ghrelin's stability and orexigenic effects. Here we studied if ghrelin-reactive Ig are associated with anxiety and depression and with the stress-induced cortisol response in a general population of adolescents. Furthermore, to test the possible infectious origin of ghrelin-reactive Ig, their levels were compared with serum IgG against common viruses. We measured ghrelin-reactive IgM, IgG and IgA in serum samples of 1199 adolescents from the Dutch TRAILS study and tested their associations with 1) anxiety and depression symptoms assessed with the Youth Self-Report, 2) stress-induced salivary cortisol levels and 3) IgG against human herpesvirus 1, 2, 4 and 6 and Influenza A and B viruses. Ghrelin-reactive IgM and IgG correlated positively with levels of antibodies against Influenza A virus. Ghrelin-reactive IgM correlated negatively with antibodies against Influenza B virus. Ghrelin-reactive IgM correlated positively with anxiety scores in girls and ghrelin-reactive IgG correlated with stress-induced cortisol secretion, but these associations were weak and not significant after correction for multiple testing. These data indicate that production of ghrelin-reactive autoantibodies could be influenced by viral infections. Serum levels of ghrelin-reactive autoantibodies probably do not play a role in regulating anxiety, depression and the stress-response in adolescents from the general population. Copyright © 2015 Elsevier Inc. All rights reserved.

Rheumatoid factor interference in immunogenicity assays for human monoclonal antibody therapeutics.

Science.gov (United States)

Tatarewicz, Suzanna; Miller, Jill M; Swanson, Steven J; Moxness, Michael S

2010-05-31

Rheumatoid factors (RFs) are endogenous human antibodies that bind to human gamma globulins. RFs demonstrate preferential binding to aggregated gamma globulins and are involved in the clearing mechanism of immune complexes. Immunoassays designed to measure human anti-human antibodies (HAHA) after administration of monoclonal antibody therapeutics are thus vulnerable to interference from RFs. When using a sensitive electrochemiluminescent (ECL) bridging immunoassay, samples from subjects with rheumatoid arthritis demonstrated much higher baseline reactivity than healthy subjects. Interference was found to be dependent on the aggregation state of the therapeutic antibody that had been conjugated with the detection reagent (ruthenium). Size exclusion high performance liquid chromatography (SE-HPLC) demonstrated that of the total integrated peaks, as little as 0.55% high molecular weight aggregates (>600kDa) were sufficient to cause increased reactivity. Stability studies of the ruthenium and biotin conjugated therapeutic antibody indicated that storage time, temperature and buffer formulation were critical in maintaining the integrity of the reagents. Through careful SE-HPLC monitoring we were able to choose appropriate storage and buffer conditions which led to a reduction in the false reactivity rate in therapeutic-naïve serum from a rheumatoid arthritis population.

Occupational trichloroethylene hypersensitivity syndrome: human herpesvirus 6 reactivation and rash phenotypes.

Science.gov (United States)

Kamijima, Michihiro; Wang, Hailan; Yamanoshita, Osamu; Ito, Yuki; Xia, Lihua; Yanagiba, Yukie; Chen, Cishan; Okamura, Ai; Huang, Zhenlie; Qiu, Xinxiang; Song, Xiangrong; Cai, Tingfeng; Liu, Lili; Ge, Yichen; Deng, Yingyu; Naito, Hisao; Yoshikawa, Tetsushi; Tohyama, Mikiko; Li, Laiyu; Huang, Hanlin; Nakajima, Tamie

2013-12-01

Trichloroethylene (TCE) is an industrial solvent which can cause severe generalized dermatitis, i.e., occupational TCE hypersensitivity syndrome. Reactivation of latent human herpesvirus 6 (HHV6) can occur in such patients, which has made TCE known as a causative chemical of drug-induced hypersensitivity syndrome (DIHS). This study aimed to clarify HHV6 status, cytokine profiles and their association with rash phenotypes in patients with TCE hypersensitivity syndrome. HHV6 DNA copy numbers, anti-HHV6 antibody titers, and cytokines were measured in blood prospectively sampled 5-7 times from 28 hospitalized patients with the disease. The patients (19 had exfoliative dermatitis (ED) and 9 had non-ED type rash) generally met the diagnostic criteria for DIHS. Viral reactivation defined as increases in either HHV6 DNA (≥100 genomic copies/10(6) peripheral blood mononuclear cells) or antibody titers was identified in 24 (89%) patients. HHV6 DNA, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-5, IL-6 and IL-10 concentrations were remarkably higher in the patients than in the healthy workers (p<0.01). Positive correlations between HHV6 DNA, TNF-α, IFN-γ, IL-6 and IL-10 were significant (p<0.05) except for that between HHV6 DNA and IFN-γ. An increase in HHV6 DNA was positively associated with an increase in TNF-α on admission (p<0.01). HHV6 DNA, the antibody titers, TNF-α and IL-10 concentrations were significantly higher in ED than in the non-ED type (p<0.05). Reactivated HHV6 and the increased cytokines could be biomarkers of TCE hypersensitivity syndrome. The higher-level reactivation and stronger humoral responses were associated with ED-type rash. Copyright © 2013 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Usefulness of the nonself-self algorithm of HLA epitope immunogenicity in the specificity analysis of monospecific antibodies induced during pregnancy

Directory of Open Access Journals (Sweden)

Rene J Duquesnoy

2015-05-01

Full Text Available Background HLAMatchmaker is a program to analyze the epitope specificities of HLA antibodies. It considers each HLA allele as a string of eplets. Intralocus and interlocus comparisons between donor and recipient alleles offer a structural assessment of compatibility and an analysis of allele panel reactivity patterns can generate information about epitope specificities of HLA antibodies. However, HLAMatchmaker cannot always generate conclusive interpretations of reactivity patterns of all monospecific antibodies which by definition recognize single epitopes. Hypothesis We have therefore developed a new antibody analysis approach that utilizes the nonself-self algorithm of HLA epitope immunogenicity. It is based in the concept that HLA antibodies originate from B-cells with immunoglobulin receptors to self HLA epitopes on one given allele and which can be activated by epitopes defined by a few nonself residue differences whereas the remainder of the structural epitope of the immunizing allele consists of self residues. Methods Three human monoclonal class I antibodies from HLA typed women sensitized during pregnancy were tested in Ig-binding assays with single alleles on a Luminex platformFindings Three new HLA epitopes were identified; they are defined by combinations of nonself and self residues for one allele of the antibody producer. Conclusion The nonself-self paradigm of HLA epitope immunogenicity offers a second approach to analyze HLA antibody specificities.

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

Science.gov (United States)

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

1992-02-01

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

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

Directory of Open Access Journals (Sweden)

Roopali eRajput

2015-09-01

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

Differential Immuno-Reactivity to Genomic DNA, RNA and Mitochondrial DNA is Associated with Auto-Immunity

Directory of Open Access Journals (Sweden)

Vilena V. Ivanova

2014-12-01

Full Text Available Background: Circulating auto-reactive antibodies are hallmark features of auto-immune diseases, however little is known with respect to the specificity of such bio-markers. In the present study, we investigated the specificity of anti-nucleic acid antibodies in the blood of subjects with systemic lupus erythematosus (SLE and healthy controls. Methods: Sera from 12 SLE cases and 8 controls were evaluated for immuno-reactivity to purified RNA, DNA and mitochondrial DNA (mtDNA by enzyme-linked immuno-sorbent assay (ELISA. Results: As expected, immuno-reactivity to total nucleic acids was significantly higher in subjects with SLE when compared to healthy controls, however a clear distinction was observed among the various nucleic acid sub-types, with sera from SLE subjects displaying the greatest immuno-reactivity to RNA followed by mtDNA and then total DNA. Conclusion: The identification of auto-reactive antibodies can serve as highly sensitive biomarkers, although their specificity may not always allow diagnostic certainty. The knowledge that auto-antibodies in subjects with SLE display differential immuno-reactivity may help to improve existing diagnostics and may lead to a better understanding of the pathogenesis of auto-immune disorders.

Immunization with Hypoallergens of shrimp allergen tropomyosin inhibits shrimp tropomyosin specific IgE reactivity.

Directory of Open Access Journals (Sweden)

Christine Y Y Wai

Full Text Available Designer proteins deprived of its IgE-binding reactivity are being sought as a regimen for allergen-specific immunotherapy. Although shrimp tropomyosin (Met e 1 has long been identified as the major shellfish allergen, no immunotherapy is currently available. In this study, we aim at identifying the Met e 1 IgE epitopes for construction of hypoallergens and to determine the IgE inhibitory capacity of the hypoallergens. IgE-binding epitopes were defined by three online computational models, ELISA and dot-blot using sera from shrimp allergy patients. Based on the epitope data, two hypoallergenic derivatives were constructed by site-directed mutagenesis (MEM49 and epitope deletion (MED171. Nine regions on Met e 1 were defined as the major IgE-binding epitopes. Both hypoallergens MEM49 and MED171 showed marked reduction in their in vitro reactivity towards IgE from shrimp allergy patients and Met e 1-sensitized mice, as well as considerable decrease in induction of mast cell degranulation as demonstrated in passive cutaneous anaphylaxis assay. Both hypoallergens were able to induce Met e 1-recognizing IgG antibodies in mice, specifically IgG2a antibodies, that strongly inhibited IgE from shrimp allergy subjects and Met e 1-sensitized mice from binding to Met e 1. These results indicate that the two designer hypoallergenic molecules MEM49 and MED171 exhibit desirable preclinical characteristics, including marked reduction in IgE reactivity and allergenicity, as well as ability to induce blocking IgG antibodies. This approach therefore offers promises for development of immunotherapeutic regimen for shrimp tropomyosin allergy.

Cell Surface Glycoprotein of Reactive Stromal Fibroblasts as a Potential Antibody Target in Human Epithelial Cancers

Science.gov (United States)

Garin-Chesa, Pilar; Old, Lloyd J.; Rettig, Wolfgang J.

1990-09-01

The F19 antigen is a cell surface glycoprotein (M_r, 95,000) of human sarcomas and proliferating, cultured fibroblasts that is absent from resting fibroblasts in normal adult tissues. Normal and malignant epithelial cells are also F19^-. The present immunohistochemical study describes induction of F19 in the reactive mesenchyme of epithelial tumors. F19^+ fibroblasts were found in primary and metastatic carcinomas, including colorectal (18 of 18 cases studied), breast (14/14), ovarian (21/21), bladder (9/10), and lung carcinomas (13/13). In contrast, the stroma of benign colorectal adenomas, fibrocystic disease and fibroadenomas of breast, benign prostate hyperplasia, in situ bladder carcinomas, and benign ovarian tumors showed no or only moderate numbers of F19^+ fibroblasts. Analysis of dermal incision wounds revealed that F19 is strongly induced during scar formation. Comparison of F19 with the extracellular matrix protein tenascin, a putative marker of tumor mesenchyme, showed a cellular staining pattern for F19 vs. the extracellular matrix pattern for tenascin and widespread expression of tenascin in F19^- normal tissues and benign tumors. Our results suggest that the F19^+ phenotype correlates with specialized fibroblast functions in wound healing and malignant tumor growth. Because of its abundance in tumor mesenchyme, F19 may serve as a target for antibodies labeled with radioisotopes or toxic agents, or inflammatogenic antibodies, in carcinoma patients.

Comparison of multiple assays for detecting human antibodies directed against antigens on normal and malignant tissue culture cells

International Nuclear Information System (INIS)

Rosenberg, S.A.; Schwarz, S.; Anding, H.; Hyatt, C.; Williams, G.M.; Johns Hopkins Univ., Baltimore, Md.

1977-01-01

Four separate assays of human antibody reactivity to four separate normal and malignant human tissue culture cells lines from two patients have been evaluated using a single highly-reactive allogeneic serum. The visual end-point cytolysis assay and the chromium-51 release assay were equally sensitive in measuring complement mediated antibody cytotoxicity and both were far more sensitive than a trypan blue dye exclusion assay. The assay of antibody reactivity by hemadsorption technique was about 10 times more sensitive than any of the cytotoxicity assays. This latter assay measures only IgG antibody however. These assays showed that cell lines from different patients may differ greatly in 'reactivity' to an allogeneic serum and emphasized the importance of utilizing tumor and normal cells from the same patient when using tissue culture cells to search for tumor specific reactivity. These observations emphasize the importance of utilizing multiple assays against paired normal and malignant cells from the same patient to be certain of the specificity and magnitude of the measured antibody

Antibody repertoire profiling with mimotope arrays

OpenAIRE

Pashova, Shina; Schneider, Christoph; von Gunten, Stephan; Pashov, Anastas

2016-01-01

Large-scale profiling and monitoring of antibody repertoires is possible through next generation sequencing (NGS), phage display libraries and microarrays. These methods can be combined in a pipeline, which ultimately maps the antibody reactivities onto defined arrays of structures - peptides or carbohydrates. The arrays can help analyze the individual specificities or can be used as complex patterns. In any case, the targets recognized should formally be considered mimotopes unless they are ...

AbMiner: A bioinformatic resource on available monoclonal antibodies and corresponding gene identifiers for genomic, proteomic, and immunologic studies

Directory of Open Access Journals (Sweden)

Shankavaram Uma

2006-04-01

Full Text Available Abstract Background Monoclonal antibodies are used extensively throughout the biomedical sciences for detection of antigens, either in vitro or in vivo. We, for example, have used them for quantitation of proteins on "reverse-phase" protein lysate arrays. For those studies, we quality-controlled > 600 available monoclonal antibodies and also needed to develop precise information on the genes that encode their antigens. Translation among the various protein and gene identifier types proved non-trivial because of one-to-many and many-to-one relationships. To organize the antibody, protein, and gene information, we initially developed a relational database in Filemaker for our own use. When it became apparent that the information would be useful to many other researchers faced with the need to choose or characterize antibodies, we developed it further as AbMiner, a fully relational web-based database under MySQL, programmed in Java. Description AbMiner is a user-friendly, web-based relational database of information on > 600 commercially available antibodies that we validated by Western blot for protein microarray studies. It includes many types of information on the antibody, the immunogen, the vendor, the antigen, and the antigen's gene. Multiple gene and protein identifier types provide links to corresponding entries in a variety of other public databases, including resources for phosphorylation-specific antibodies. AbMiner also includes our quality-control data against a pool of 60 diverse cancer cell types (the NCI-60 and also protein expression levels for the NCI-60 cells measured using our high-density "reverse-phase" protein lysate microarrays for a selection of the listed antibodies. Some other available database resources give information on antibody specificity for one or a couple of cell types. In contrast, the data in AbMiner indicate specificity with respect to the antigens in a pool of 60 diverse cell types from nine different

AbMiner: a bioinformatic resource on available monoclonal antibodies and corresponding gene identifiers for genomic, proteomic, and immunologic studies.

Science.gov (United States)

Major, Sylvia M; Nishizuka, Satoshi; Morita, Daisaku; Rowland, Rick; Sunshine, Margot; Shankavaram, Uma; Washburn, Frank; Asin, Daniel; Kouros-Mehr, Hosein; Kane, David; Weinstein, John N

2006-04-06

Monoclonal antibodies are used extensively throughout the biomedical sciences for detection of antigens, either in vitro or in vivo. We, for example, have used them for quantitation of proteins on "reverse-phase" protein lysate arrays. For those studies, we quality-controlled > 600 available monoclonal antibodies and also needed to develop precise information on the genes that encode their antigens. Translation among the various protein and gene identifier types proved non-trivial because of one-to-many and many-to-one relationships. To organize the antibody, protein, and gene information, we initially developed a relational database in Filemaker for our own use. When it became apparent that the information would be useful to many other researchers faced with the need to choose or characterize antibodies, we developed it further as AbMiner, a fully relational web-based database under MySQL, programmed in Java. AbMiner is a user-friendly, web-based relational database of information on > 600 commercially available antibodies that we validated by Western blot for protein microarray studies. It includes many types of information on the antibody, the immunogen, the vendor, the antigen, and the antigen's gene. Multiple gene and protein identifier types provide links to corresponding entries in a variety of other public databases, including resources for phosphorylation-specific antibodies. AbMiner also includes our quality-control data against a pool of 60 diverse cancer cell types (the NCI-60) and also protein expression levels for the NCI-60 cells measured using our high-density "reverse-phase" protein lysate microarrays for a selection of the listed antibodies. Some other available database resources give information on antibody specificity for one or a couple of cell types. In contrast, the data in AbMiner indicate specificity with respect to the antigens in a pool of 60 diverse cell types from nine different tissues of origin. AbMiner is a relational database that

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

OpenAIRE

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

2018-01-01

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

Broad cross-reactive IgG responses elicited by adjuvanted vaccination with recombinant influenza hemagglutinin (rHA) in ferrets and mice

Science.gov (United States)

Wang, Jiong; Hilchey, Shannon P.; DeDiego, Marta; Perry, Sheldon; Hyrien, Ollivier; Nogales, Aitor; Garigen, Jessica; Amanat, Fatima; Huertas, Nelson; Krammer, Florian; Martinez-Sobrido, Luis; Topham, David J.; Treanor, John J.; Sangster, Mark Y.

2018-01-01

Annual immunization against influenza virus is a large international public health effort. Accumulating evidence suggests that antibody mediated cross-reactive immunity against influenza hemagglutinin (HA) strongly correlates with long-lasting cross-protection against influenza virus strains that differ from the primary infection or vaccination strain. However, the optimal strategies for achieving highly cross-reactive antibodies to the influenza virus HA have not yet to be defined. In the current study, using Luminex-based mPlex-Flu assay, developed by our laboratory, to quantitatively measure influenza specific IgG antibody mediated cross-reactivity, we found that prime-boost-boost vaccination of ferrets with rHA proteins admixed with adjuvant elicited higher magnitude and broader cross-reactive antibody responses than that induced by actual influenza viral infection, and this cross-reactive response likely correlated with increased anti-stalk reactive antibodies. We observed a similar phenomenon in mice receiving three sequential vaccinations with rHA proteins from either A/California/07/2009 (H1N1) or A/Hong Kong/1/1968 (H3N2) viruses admixed with Addavax, an MF59-like adjuvant. Using this same mouse vaccination model, we determined that Addavax plays a more significant role in the initial priming event than in subsequent boosts. We also characterized the generation of cross-reactive antibody secreting cells (ASCs) and memory B cells (MBCs) when comparing vaccination to viral infection. We have also found that adjuvant plays a critical role in the generation of long-lived ASCs and MBCs cross-reactive to influenza viruses as a result of vaccination with rHA of influenza virus, and the observed increase in stalk-reactive antibodies likely contributes to this IgG mediated broad cross-reactivity. PMID:29641537

Use of JH4 joining segment gene by an anti-arsonate antibody that bears the major A-strain cross-reactive idiotype but displays diminished antigen binding.

Science.gov (United States)

Slaughter, C A; Jeske, D J; Kuziel, W A; Milner, E C; Capra, J D

1984-06-01

One of the antibody families utilized by the A/J mouse in its response to p-azophenylarsonate (Ars) is characterized by the expression of the major anti-arsonate cross-reactive idiotype (CRI) of the A strain. This family has been termed the Ars-A family. A hybridoma antibody (HP 101F11 ) obtained after immunization of an A/J mouse with Ars was identified initially as displaying the CRI, but was subsequently found to bind antigen at a level much lower than most members of the Ars-A family. The results of binding studies suggested that HP 101F11 possesses reduced avidity for antigen. When isolated light and heavy chains were allowed to recombine with the heavy and light chains of a strongly antigen-binding, strongly CRI-positive antibody of the Ars-A family (HP 93G7 ), the low level of antigen binding by HP 101F11 was found to be due to a structurally variant heavy chain. Whereas antibodies of the Ars-A family with normal avidity for antigen had been shown to use the JH2 joining segment gene, amino acid sequence analysis of HP 101F11 revealed that this antibody has a JH segment with a sequence identical to that encoded by a portion of a different JH gene, JH4 . The implication that 101F11 uses the JH4 gene instead of JH2 was supported by the observation that the productively rearranged gene is associated with an Eco R1 restriction fragment 0.95 Kb smaller than the corresponding fragments of Ars-A hybridomas with normal avidity for antigen. The size difference of 0.95 Kb corresponds exactly to the known distance between the JH2 and JH4 genes in BALB/c germline DNA. In addition to the structural differences immediately attributable to the use of JH4 , HP 101F11 has shown an amino acid interchange in the DH segment, and a single amino acid deletion at the DH-JH boundary. These results show that variation among members of the Ars-A family in the DH and/or JH segments provides alternative structural forms of Ars-A antibodies upon which selective processes can operate

Broadly-reactive human monoclonal antibodies elicited following pandemic H1N1 influenza virus exposure protect mice from highly pathogenic H5N1 challenge.

Science.gov (United States)

Nachbagauer, Raffael; Shore, David; Yang, Hua; Johnson, Scott K; Gabbard, Jon D; Tompkins, S Mark; Wrammert, Jens; Wilson, Patrick C; Stevens, James; Ahmed, Rafi; Krammer, Florian; Ellebedy, Ali H

2018-06-13

Broadly cross-reactive antibodies that recognize conserved epitopes within the influenza virus hemagglutinin (HA) stalk domain are of particular interest for their potential use as therapeutic and prophylactic agents against multiple influenza virus subtypes including zoonotic virus strains. Here, we characterized four human HA stalk-reactive monoclonal antibodies (mAbs) for their binding breadth and affinity, in vitro neutralization capacity, and in vivo protective potential against an highly pathogenic avian influenza virus. The monoclonal antibodies were isolated from individuals shortly following infection with (70-1F02 and 1009-3B05) or vaccination against (05-2G02 and 09-3A01) A(H1N1)pdm09. Three of the mAbs bound HAs from multiple strains of group 1 viruses, and one mAb, 05-2G02, bound to both group 1 and group 2 influenza A HAs. All four antibodies prophylactically protected mice against a lethal challenge with the highly pathogenic A/Vietnam/1203/04 (H5N1) strain. Two mAbs, 70-1F02 and 09-3A01, were further tested for their therapeutic efficacy against the same strain and showed good efficacy in this setting as well. One mAb, 70-1F02, was co-crystallized with H5 HA and showed similar heavy chain only interactions as a the previously described anti-stalk antibody CR6261. Finally, we showed that antibodies that compete with these mAbs are prevalent in serum from an individual recently infected with A(H1N1)pdm09 virus. The antibodies described here can be developed into broad-spectrum antiviral therapeutics that could be used to combat infections with zoonotic or emerging pandemic influenza viruses. IMPORTANCE The rise in zoonotic infections of humans with emerging influenza viruses is a worldwide public health concern. The majority of recent zoonotic human influenza cases were caused by H7N9 and H5Nx viruses and were associated with high morbidity and mortality. In addition, seasonal influenza viruses are estimated to cause up to 650,000 deaths annually

Acute HIV Discovered During Routine HIV Screening With HIV Antigen-Antibody Combination Tests in 9 US Emergency Departments.

Science.gov (United States)

White, Douglas A E; Giordano, Thomas P; Pasalar, Siavash; Jacobson, Kathleen R; Glick, Nancy R; Sha, Beverly E; Mammen, Priya E; Hunt, Bijou R; Todorovic, Tamara; Moreno-Walton, Lisa; Adomolga, Vincent; Feaster, Daniel J; Branson, Bernard M

2018-01-05

Newer combination HIV antigen-antibody tests allow detection of HIV sooner after infection than previous antibody-only immunoassays because, in addition to HIV-1 and -2 antibodies, they detect the HIV-1 p24 antigen, which appears before antibodies develop. We determine the yield of screening with HIV antigen-antibody tests and clinical presentations for new diagnoses of acute and established HIV infection across US emergency departments (EDs). This was a retrospective study of 9 EDs in 6 cities with HIV screening programs that integrated laboratory-based antigen-antibody tests between November 1, 2012, and December 31, 2015. Unique patients with newly diagnosed HIV infection were identified and classified as having either acute HIV infection or established HIV infection. Acute HIV infection was defined as a repeatedly reactive antigen-antibody test result, a negative HIV-1/HIV-2 antibody differentiation assay, or Western blot result, but detectable HIV ribonucleic acid (RNA); established HIV infection was defined as a repeatedly reactive antigen-antibody test result and a positive HIV-1/HIV-2 antibody differentiation assay or Western blot result. The primary outcomes were the number of new HIV diagnoses and proportion of patients with laboratory-defined acute HIV infection. Secondary outcomes compared reason for visit and the clinical presentation of acute HIV infection. In total, 214,524 patients were screened for HIV and 839 (0.4%) received a new diagnosis, of which 122 (14.5%) were acute HIV infection and 717 (85.5%) were established HIV infection. Compared with patients with established HIV infection, those with acute HIV infection were younger, had higher RNA and CD4 counts, and were more likely to have viral syndrome (41.8% versus 6.5%) or fever (14.3% versus 3.4%) as their reason for visit. Most patients with acute HIV infection displayed symptoms attributable to acute infection (median symptom count 5 [interquartile range 3 to 6]), with fever often

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

Directory of Open Access Journals (Sweden)

Merima Bublin

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

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

Science.gov (United States)

Bublin, Merima; Kostadinova, Maria; Fuchs, Julian E; Ackerbauer, Daniela; Moraes, Adolfo H; Almeida, Fabio C L; Lengger, Nina; Hafner, Christine; Ebner, Christof; Radauer, Christian; Liedl, Klaus R; Valente, Ana Paula; Breiteneder, Heimo

2015-01-01

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

Monoclonal Antibody Production against Human Spermatozoal Surface Antigens

Directory of Open Access Journals (Sweden)

M Jedi-Tehrani

2005-10-01

Full Text Available Introduction: As monoclonal antibodies are potential tools for characterization of soluble or cellular surface antigens, use of these proteins has always been considered in infertility and reproduction research. Therefore, in this study, monoclonal antibodies against human sperm surface antigens were produced. Material and Methods: To produce specific clones against human sperm surface antigens, proteins were extracted using solubilization methods. Balb/c mice were immunized intraperitoneally with the proteins using complete Freund’s adjuvant in the first injection and incomplete Adjuvant in the following booster injections. Hybridoma cells producing ASA were cloned by limiting dilution. Results: Five stable ASA producing hybridoma clones were achieved and their antibody isotypes were determined by ELISA. All the isotypes were of IgG class. Their cross reactivity with rat and mice spermatozoa was examined but they did not have any cross reactivity. Conclusion: The produced antibodies can be used in further studies to characterize and evaluate each of the antigens present on human sperm surface and determining their role in fertilization.

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

Science.gov (United States)

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

2013-08-28

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

Immunity to rhabdoviruses in rainbow trout: the antibody response

DEFF Research Database (Denmark)

Lorenzen, Niels; Lapatra, S.E.

1999-01-01

to their occasional detrimental effect on rainbow trout farming. Research efforts have been focused on understanding the mechanisms involved in protective immunity. Several specific and nonspecific cellular and humoral parameters are believed to be involved, but only the antibody response has been characterised......, have demonstrated that rainbow trout can produce specific and highly functional antibodies that are able to neutralise virus pathogenicity in vitro as well as in vivo. The apparently more restricted antibody response to IHNV and VHSV antigens in fish compared to mammals could possibly be explained...... aspects of antibody response and antibody reactivity with IHNV and VHSV antigens....

Large Scale Genome Analysis Shows that the Epitopes for Broadly Cross-Reactive Antibodies Are Predominant in the Pandemic 2009 Influenza Virus A H1N1 Strain

Directory of Open Access Journals (Sweden)

Edgar E. Lara-Ramírez

2013-11-01

Full Text Available The past pandemic strain H1N1 (A (H1N1pdm09 has now become a common component of current seasonal influenza viruses. It has changed the pre-existing immunity of the human population to succeeding infections. In the present study, a total of 14,210 distinct sequences downloaded from National Center for Biotechnology Information (NCBI database were used for the analysis. The epitope compositions in A (H1N1pdm09, classic seasonal strains, swine strains as well as highly virulent avian strain H5N1, identified with the aid of the Immune Epitope DataBase (IEDB, were compared at genomic level. The result showed that A (H1N1 pdm09 contains the 90% of B-cell epitopes for broadly cross-reactive antibodies (EBCA, which is in consonance with the recent reports on the experimental identification of new epitopes or antibodies for this virus and the binding tests with influenza virus protein HA of different subtypes. Our analysis supports that high proportional EBCA depends on the epitope pattern of A (H1N1pdm09 virus. This study may be helpful for better understanding of A (H1N1pdm09 and the production of new influenza vaccines.

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

Directory of Open Access Journals (Sweden)

S Kashaninan

2014-12-01

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

Simultaneous identification of Trypanosoma cruzi surface and internal antigens reactive to different immunoglobulin classes (radio-immunoblotting)

International Nuclear Information System (INIS)

Stolf, A.M.S.; Umezawa, E.S.; Zingales, B.

1990-01-01

A radioactive Western blotting technique was developed by which the reactivity of Immunoglobulins (IGs) from different classes to both membrane radiolabelled and internal parasite antigens is simultaneously identified. The method includes radioiodination of parasites, polypeptide fractionation by SDS-PAGE, Western-blot transfer and autoradiography of the immunoblots developed with anti-Igs conjugates labelled with enzymes. The analysis is then performed by the comparison of common bands on the autoradiograms and the respective substrate stained nitrocellulose blots. This technique was used to analyse. T.cruzi trypomastigote surface labelled antigens reactive to IgM, IgA and IgC specific antibodies. A different pattern of reactivity with acute Chagas disease patients sera was thus obtained. (author)

Hepatitis B virus reactivation during immunosuppressive therapy: Appropriate risk stratification.

Science.gov (United States)

Seto, Wai-Kay

2015-04-28

Our understanding of hepatitis B virus (HBV) reactivation during immunosuppresive therapy has increased remarkably during recent years. HBV reactivation in hepatitis B surface antigen (HBsAg)-positive individuals has been well-described in certain immunosuppressive regimens, including therapies containing corticosteroids, anthracyclines, rituximab, antibody to tumor necrosis factor (anti-TNF) and hematopoietic stem cell transplantation (HSCT). HBV reactivation could also occur in HBsAg-negative, antibody to hepatitis B core antigen (anti-HBc) positive individuals during therapies containing rituximab, anti-TNF or HSCT.For HBsAg-positive patients, prophylactic antiviral therapy is proven to the effective in preventing HBV reactivation. Recent evidence also demonstrated entecavir to be more effective than lamivudine in this aspect. For HBsAg-negative, anti-HBc positive individuals, the risk of reactivations differs with the type of immunosuppression. For rituximab, a prospective study demonstrated the 2-year cumulative risk of reactivation to be 41.5%, but prospective data is still lacking for other immunosupressive regimes. The optimal management in preventing HBV reactivation would involve appropriate risk stratification for different immunosuppressive regimes in both HBsAg-positive and HBsAg-negative, anti-HBc positive individuals.

Anti-Taenia solium monoclonal antibodies for the detection of parasite antigens in body fluids from patients with neurocysticercosis.

Science.gov (United States)

Paredes, Adriana; Sáenz, Patricia; Marzal, Miguel W; Orrego, Miguel A; Castillo, Yesenia; Rivera, Andrea; Mahanty, Siddhartha; Guerra-Giraldez, Cristina; García, Hector H; Nash, Theodore E

2016-07-01

Neurocysticercosis (NCC), an infection of the brain by Taenia solium (Ts) cysts, is the most common cause of adult-onset epilepsy in developing countries. Serological testing consists primarily of varying methods to detect antibodies in body fluids and more recently antigen (Ag) detection assays to identify individuals or animals with viable parasites. Antigen assays currently in use employ monoclonal antibodies (mAbs) raised against T. saginata, which have known cross reactivity to animal cestodes but are highly specific in human samples. We produced, characterized and tested 21 mAbs raised against T. solium whole cyst antigens, vesicular fluid or excretory secretory products. Reactivity of the TsmAbs against specific cyst structures was determined using immunofluorescence and immunohistochemistry on histological sections of Ts muscle cysts. Four TsmAbs reacted to vesicular space alone, 9 to the neck and cyst wall, one to the neck and vesicular space and 7 to the neck, cyst wall and vesicular space. An in-house ELISA assay to detect circulating Ts antigen, using the TsmAbs as capture antibodies and a rabbit polyclonal anti-Ts whole cyst antibody as a detector antibody demonstrated that eight of the 21 TsmAbs detected antigens in known NCC-positive human sera and three of these also in urine samples. Reactivity was expressed as normalized ratios of optical densities (OD positive control/OD negative control). Three TsmAbs had ratios >10 and five between 2 and 10. The TsmAbs have potential utility for the diagnosis and post-treatment monitoring of patients with viable NCC infections. Copyright © 2016 Elsevier Inc. All rights reserved.

Anti-nucleosome antibodies complexed to nucleosomal antigens show anti-DNA reactivity and bind to rat glomerular basement membrane in vivo.

Science.gov (United States)

Kramers, C; Hylkema, M N; van Bruggen, M C; van de Lagemaat, R; Dijkman, H B; Assmann, K J; Smeenk, R J; Berden, J H

1994-01-01

Histones can mediate the binding of DNA and anti-DNA to the glomerular basement membrane (GBM). In ELISA histone/DNA/anti-DNA complexes are able to bind to heparan sulfate (HS), an intrinsic constituent of the GBM. We questioned whether histone containing immune complexes are able to bind to the GBM, and if so, whether the ligand in the GBM is HS. Monoclonal antibodies (mAbs) complexed to nucleosomal antigens and noncomplexed mAbs were isolated from culture supernatants of four IgG anti-nuclear mAbs. All noncomplexed mAbs showed strong anti-nucleosome reactivity in ELISA. One of them showed in addition anti-DNA reactivity in noncomplexed form. The other three mAbs only showed anti-DNA reactivity when they were complexed to nucleosomal antigens. After renal perfusion a fine granular binding of complexed mAbs to the glomerular capillary wall and activation of complement was observed in immunofluorescence, whereas noncomplexed mAbs did not bind. Immuno-electron microscopy showed binding of complexes to the whole width of the GBM. When HS in the GBM was removed by renal heparinase perfusion the binding of complexed mAb decreased, but did not disappear completely. We conclude that anti-nucleosome mAbs, which do not bind DNA, become DNA reactive once complexed to nucleosomal antigens. These complexed mAbs can bind to the GBM. The binding ligand in the GBM is partly, but not solely, HS. Binding to the GBM of immune complexes containing nucleosomal material might be an important event in the pathogenesis of lupus nephritis. Images PMID:8040312

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

Directory of Open Access Journals (Sweden)

Elena Makoveichuk

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

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

Science.gov (United States)

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

2017-01-01

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

A human monoclonal antibody drug and target discovery platform for B-cell chronic lymphocytic leukemia based on allogeneic hematopoietic stem cell transplantation and phage display.

Science.gov (United States)

Baskar, Sivasubramanian; Suschak, Jessica M; Samija, Ivan; Srinivasan, Ramaprasad; Childs, Richard W; Pavletic, Steven Z; Bishop, Michael R; Rader, Christoph

2009-11-12

Allogeneic hematopoietic stem cell transplantation (alloHSCT) is the only potentially curative treatment available for patients with B-cell chronic lymphocytic leukemia (B-CLL). Here, we show that post-alloHSCT antibody repertoires can be mined for the discovery of fully human monoclonal antibodies to B-CLL cell-surface antigens. Sera collected from B-CLL patients at defined times after alloHSCT showed selective binding to primary B-CLL cells. Pre-alloHSCT sera, donor sera, and control sera were negative. To identify post-alloHSCT serum antibodies and subsequently B-CLL cell-surface antigens they recognize, we generated a human antibody-binding fragment (Fab) library from post-alloHSCT peripheral blood mononuclear cells and selected it on primary B-CLL cells by phage display. A panel of Fab with B-CLL cell-surface reactivity was strongly enriched. Selection was dominated by highly homologous Fab predicted to bind the same antigen. One Fab was converted to immunoglobulin G1 and analyzed for reactivity with peripheral blood mononuclear cells from B-CLL patients and healthy volunteers. Cell-surface antigen expression was restricted to primary B cells and up-regulated in primary B-CLL cells. Mining post-alloHSCT antibody repertoires offers a novel route to discover fully human monoclonal antibodies and identify antigens of potential therapeutic relevance to B-CLL and possibly other cancers. Trials described herein were registered at www.clinicaltrials.gov as nos. NCT00055744 and NCT00003838.

Antibody conjugate radioimmunotherapy of superficial bladder cancer

International Nuclear Information System (INIS)

Perkins, Alan; Hopper, Melanie; Murray, Andrea; Frier, Malcolm; Bishop, Mike

2002-01-01

The administration of antibody conjugates for cancer therapy is now proving to be of clinical value. We are currently undertaking a programme of clinical studies using the monoclonal antibody C 595 (gG3) which reacts with the MUC1 glycoprotein antigen that is aberrantly expressed in a high proportion of bladder tumours. Radio immuno conjugates of the C 595 antibody have been produced with high radiolabelling efficiency and immuno reactivity using Tc-99 m and In-111 for diagnostic imaging, and disease staging and the cytotoxic radionuclides Cu-67 and Re-188 for therapy of superficial bladder cancer. A Phase I/II therapeutic trail involving the intravesical administration of antibody directly into the bladder has now begun. (author)

Heterogeneity of neutrophil antibodies in patients with primary Sjögren's syndrome.

Science.gov (United States)

Lamour, A; Le Corre, R; Pennec, Y L; Cartron, J; Youinou, P

1995-11-01

Our aims were to determine the prevalence of neutrophil antibodies in patients with primary Sjögren's syndrome (pSS), identify their target antigen(s), and evaluate their functional significance. Neutrophil antibodies were detected using an indirect immunofluorescence (IIIF) test and an enzyme-linked immunosorbent assay (ELISA), using recombinant human Fc-gamma receptor (Fc gamma RIIIb) as a capture agent. Luminol-dependent chemiluminescence was then measured by an established technique. Antibodies to neutrophils were detected in 30 of 66 patients (45%) and categorized on the basis of positivity for the two assays: IIF+/ELISA+ (group A: five patients), IIF+/ELISA- (group B: five patients), and IFF-/ELISA+ (group C: 20 patients). All positive sera contained antibodies directed to the neutrophil specific Fc gamma RIIIb, and none of them bound to NAnull neutrophils. The titer of neutrophil-reactive antibodies (groups A and B) showed no correlation with the neutrophil count, but these autoantibodies did reduce the cell ability to generate a respiratory burst. Thus, neutrophil antibodies are common in patients with pSS. Their main target appears to be Fc gamma RIII, and this may partly account for the dysfunction in Fc gamma R-mediated clearance by the reticuloendothelial system reported in these patients.

The Antitumor Effect of Single-domain Antibodies Directed Towards Membrane-associated Catalase and Superoxide Dismutase.

Science.gov (United States)

Bauer, Georg; Motz, Manfred

2016-11-01

Neutralizing single-domain antibodies directed towards catalase or superoxide dismutase (SOD) caused efficient reactivation of intercellular reactive oxygen species/reactive nitrogen species (ROS/RNS)-dependent apoptosis-inducing signaling specifically in human tumor cells. Single-domain antibodies targeted tumor cell-specific membrane-associated SOD and catalase, but not the corresponding intracellular enzymes. They were shown to be about 200-fold more effective than corresponding classical recombinant antigen-binding fragments and more than four log steps more efficient than monoclonal antibodies. Combined addition of single-domain antibodies against catalase and SOD caused a remarkable synergistic effect. Proof-of-concept experiments in immunocompromised mice using human tumor xenografts and single-domain antibodies directed towards SOD showed an inhibition of tumor growth. Neutralizing single-domain antibodies directed to catalase and SOD also caused a very strong synergistic effect with the established chemotherapeutic agent taxol, indicating an overlap of signaling pathways. This effect might also be useful in order to avoid unwanted side-effects and to drastically lower the costs for taxol-based therapy. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Noninvasive diagnosis of axillary node metastases with monoclonal antibody lymphoscintigraphy

International Nuclear Information System (INIS)

Fig, L.M.; Von Moll, L.; Brown, R.; Harness, J.; Appleman, H.; Stevens, R.; Johnson, J.W.; Mudgett, E.; Colcher, D.; Schlom, J.; Lichter, A.; Wicha, M.; Wahl, R.L.

1989-01-01

This study was undertaken to determine whether 131-I labeled B72.3 monoclonal antibody, when injected subcutaneously in patients with known breast cancer, successfully detects lymph node metastases. Eleven women with biopsy-proven B72.3 antibody-reactive breast cancer (determined by immunoperoxidase staining) received subcutaneous injections of 500 μ Ci 131-I B72.3 in ipsilateral finger web spaces (or, in three cases, intralesional injections into the site of the breast tumor). The antibody is a IgGlk reactive with a high molecular weight antigen found on most breast carcinomas. Images of the axilla were obtained immediately after injection and serially to 72 hours. Nodal uptake was scored on a 0-3+ scale in a blinded fashion and correlated with pathologic findings from lymph node dissection

Immunoglobulin-E reactivity to wine glycoproteins in heavy drinkers

DEFF Research Database (Denmark)

Gonzalez-Quintela, Arturo; Gomez-Rial, Jose; Valcarcel, Catalina

2011-01-01

and biological significance of IgE antibodies to N-glycans from wine glycoproteins in heavy drinkers. A structured questionnaire, skin prick tests, serum IgE levels, IgE-immunoblotting to wine extracts, and basophil activation tests were used to characterize 20 heavy drinkers and 10 control subjects. Eleven...... heavy drinkers (55%) showed IgE binding to proteins in wine extracts. The proteins were identified by mass spectrometry as grape-derived vacuolar invertase and thaumatin-like protein. Immunoblot reactivity was closely associated with the presence of IgE to CCDs and was inhibited by preincubation...... with a glycoconjugate containing bromelain-type N-glycans. The same conjugate, CCD-bearing allergens, and wine extracts activated basophils in patients with high-titer CCD-specific IgE but not in healthy controls. There was no relationship between immunoblot reactivity and consumption of any specific type of wine...

Serum IgG antibodies from healthy subjects up to 100 years old react to JC polyomavirus.

Science.gov (United States)

Bononi, Ilaria; Mazzoni, Elisa; Pietrobon, Silvia; Manfrini, Marco; Torreggiani, Elena; Rossini, Marika; Lotito, Francesca; Guerra, Giovanni; Rizzo, Paola; Martini, Fernanda; Tognon, Mauro

2018-08-01

JC polyomavirus (JCPyV) was identified in 1971 in the brain tissue of a patient (J.C.) affected by the progressive multifocal leukoencephalopathy (PML). JCPyV encodes for the oncoproteins large T antigen (Tag) and small t-antigen (tag). These oncoproteins are responsible of the cell transformation and tumorigenesis in experimental animals. JCPyV is ubiquitous in human populations. After the primary infection, which is usually asymptomatic, JCPyV remains lifelong in the host in a latent phase. Its reactivation may occur in heathy subjects and immunocompromised patients. Upon reactivation, JCPyV could reach (i) the CNS inducing the PML, (ii) the kidney of transplant patients causing the organ rejection. Association between JCPyV, which is a small DNA tumor virus, and gliomas and colorectal carcinomas has been published. In the present investigation, we report on a new indirect ELISA with two specific synthetic peptides mimicking JCPyV VP1 immunogenic epitopes to detect specific serum IgG antibodies against JCPyV. Serum samples of healthy subjects (n = 355) ranging 2-100 years old, were analyzed by this new indirect ELISA. The linear peptides VP1 K and VP1 N resemble the natural JCPyV VP1 capsidic epitopes constituting a docking site for serum antibodies. Data from this innovative immunologic assay indicate that the overall prevalence of JCPyV-VP1 antibodies in healthy subjects is at 39%. The innovative indirect ELISA with JCPyV VP1 mimotopes seems to be a useful method to detect specific IgG antibodies against this virus, without cross-reactivity with the closely related SV40 and BKPyV polyomaviruses. © 2018 Wiley Periodicals, Inc.

Monoclonal antibody-based Surface Plasmon Resonance sensors for pathogen detection

DEFF Research Database (Denmark)

Skottrup, Peter Durand

2007-01-01

.sp. tritici, the cause of wheat yellow rust and Phytophthora infestans, the cause of late blight disease in potato. As no antibody existed against urediniospores from P. striiformis, mouse monoclonal antibodies (mAbs) were produced and characterised. IgM-isotype mAbs from nine hybridoma cell lines were...... to the initial cell concentration. Assay performance was investigated by cross-reactivity studies against other rust fungi. Cross-reactivity was found with Puccinia recondita and Puccinia hordei, suggesting that the ~ 39 kDa mAb8-antigen might be a conserved structural component in the surface of Puccinia...

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

Directory of Open Access Journals (Sweden)

Hust Michael

2008-09-01

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

Self assertion modeled as a network repertoire of multi-determinant antibodies

NARCIS (Netherlands)

Takumi, K.; Boer, R.J. de

1996-01-01

We study repertoire selection in a network of natural antibodies that is maintained by stimulatory idiotypic interactions. The natural antibody repertoire develops in an environment of self epitopes to which the self-reactive B cell clones are completely tolerant. For the modeling formalism, we

Metabolomics reveals distinct, antibody-independent, molecular signatures of MS, AQP4-antibody and MOG-antibody disease.

Science.gov (United States)

Jurynczyk, Maciej; Probert, Fay; Yeo, Tianrong; Tackley, George; Claridge, Tim D W; Cavey, Ana; Woodhall, Mark R; Arora, Siddharth; Winkler, Torsten; Schiffer, Eric; Vincent, Angela; DeLuca, Gabriele; Sibson, Nicola R; Isabel Leite, M; Waters, Patrick; Anthony, Daniel C; Palace, Jacqueline

2017-12-06

The overlapping clinical features of relapsing remitting multiple sclerosis (RRMS), aquaporin-4 (AQP4)-antibody (Ab) neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein (MOG)-Ab disease mean that detection of disease specific serum antibodies is the gold standard in diagnostics. However, antibody levels are not prognostic and may become undetectable after treatment or during remission. Therefore, there is still a need to discover antibody-independent biomarkers. We sought to discover whether plasma metabolic profiling could provide biomarkers of these three diseases and explore if the metabolic differences are independent of antibody titre. Plasma samples from 108 patients (34 RRMS, 54 AQP4-Ab NMOSD, and 20 MOG-Ab disease) were analysed by nuclear magnetic resonance spectroscopy followed by lipoprotein profiling. Orthogonal partial-least squares discriminatory analysis (OPLS-DA) was used to identify significant differences in the plasma metabolite concentrations and produce models (mathematical algorithms) capable of identifying these diseases. In all instances, the models were highly discriminatory, with a distinct metabolite pattern identified for each disease. In addition, OPLS-DA identified AQP4-Ab NMOSD patient samples with low/undetectable antibody levels with an accuracy of 92%. The AQP4-Ab NMOSD metabolic profile was characterised by decreased levels of scyllo-inositol and small high density lipoprotein particles along with an increase in large low density lipoprotein particles relative to both RRMS and MOG-Ab disease. RRMS plasma exhibited increased histidine and glucose, along with decreased lactate, alanine, and large high density lipoproteins while MOG-Ab disease plasma was defined by increases in formate and leucine coupled with decreased myo-inositol. Despite overlap in clinical measures in these three diseases, the distinct plasma metabolic patterns support their distinct serological profiles and confirm that these

Mycobacterium leprae antigens involved in human immune responses. I. Identification of four antigens by monoclonal antibodies

Energy Technology Data Exchange (ETDEWEB)

Britton, W.J.; Hellqvist, L.; Basten, A.; Raison, R.L.

1985-12-01

Four distinct antigens were identified in soluble sonicates of Mycobacterium leprae by using a panel of 11 monoclonal antibodies. Cross-reactivity studies with other mycobacterial species were conducted by using ELISA and immunoblot assays, and demonstrated that determinants on two of the antigens were present in many mycobacteria, whereas the other two were limited in distribution. Competitive inhibition experiments with radiolabeled monoclonal antibodies showed cross-inhibition between antibodies identifying two of the four antigenicbands. These two bands, of M/sub tau/ 4.5 to 6 KD and 30 to 40 KD, were resistant to protease treatment after immunoblotting. In contrast the two other bands of 16 and 70 KD were protease-sensitive. Although all four bands reacted with some human lepromatous leprosy sera in immunoblots, the 4.5 to 6 KD and 30 to 40 KD bands were most prominent. Lepromatous leprosy sera also inhibited the binding of radiolabeled monoclonal antibodies to each of the four antigens, with the mean titer causing 50% inhibition being higher for antibodies reacting with the 4.5 to 6 KD and 30 to 40 KD bands. These findings indicated that all four antigens were involved in the human B cell response to M. leprae.

Mycobacterium leprae antigens involved in human immune responses. I. Identification of four antigens by monoclonal antibodies

International Nuclear Information System (INIS)

Britton, W.J.; Hellqvist, L.; Basten, A.; Raison, R.L.

1985-01-01

Four distinct antigens were identified in soluble sonicates of Mycobacterium leprae by using a panel of 11 monoclonal antibodies. Cross-reactivity studies with other mycobacterial species were conducted by using ELISA and immunoblot assays, and demonstrated that determinants on two of the antigens were present in many mycobacteria, whereas the other two were limited in distribution. Competitive inhibition experiments with radiolabeled monoclonal antibodies showed cross-inhibition between antibodies identifying two of the four antigenicbands. These two bands, of M/sub tau/ 4.5 to 6 KD and 30 to 40 KD, were resistant to protease treatment after immunoblotting. In contrast the two other bands of 16 and 70 KD were protease-sensitive. Although all four bands reacted with some human lepromatous leprosy sera in immunoblots, the 4.5 to 6 KD and 30 to 40 KD bands were most prominent. Lepromatous leprosy sera also inhibited the binding of radiolabeled monoclonal antibodies to each of the four antigens, with the mean titer causing 50% inhibition being higher for antibodies reacting with the 4.5 to 6 KD and 30 to 40 KD bands. These findings indicated that all four antigens were involved in the human B cell response to M. leprae

Failure of anti-T-cell receptor V beta antibodies to consistently identify a malignant T-cell clone in Sézary syndrome.

Science.gov (United States)

Bigler, R D; Boselli, C M; Foley, B; Vonderheid, E C

1996-11-01

Monoclonal antibodies (MAbs) reacting with the human T cell receptor (TCR) V beta or V alpha region have been shown to be almost as specific as a private idiotypic MAb in identifying T cell clones. When available, V beta-specific MAbs offer the ease of immunofluorescence analysis to identify and quantitate expanded malignant or nonmalignant T cell populations without requiring polymerase chain reaction (PCR) technology to evaluate expression of V beta gene families. The V beta expression of peripheral blood lymphocytes from twenty-three consecutive patients with Sézary syndrome has been analyzed by reverse transcriptase (RT)-PCR. Ten patients had malignant T cell clones that expressed a TCR V beta corresponding to a commercially available anti-V beta antibody. Immunofluorescence staining with anti-V beta MAbs showed a direct correlation with RT-PCR results in seven of ten patients. No false positive reactivity was noted on immunofluorescence staining with any MAb. Cells from three patients, however, did not react with the corresponding anti-V beta MAb. These three cases expressed a TCR V beta from gene families containing a single member, ie, V beta 14, V beta 18, and V beta 20, yet MAbs reported to be specific for these regions failed to react with the T cell clone from these patients. Sequencing of the PCR product in these cases confirmed the RT-PCR results. Cells from two patients expressed a TCR using V beta 5.1-D beta 1.1 genes with different J-C segments. One patient's cells reacted with an anti-V beta 5.1 MAb (LC4) whereas the other patient's cells bound one-tenth the amount of this same MAb. These results indicate that currently available anti-TCR V region MAbs may not react consistently with T cell clones expressing the corresponding V region or may react with a low affinity making detection difficult. Differences in the J-C junction or in CDR3 may influence the binding of these MAbs. Until the false negative rate is reduced and the fine specificity and

Human antibody responses to Schistosoma mansoni: does antigen directed, isotype restriction result in the production of blocking antibodies?

Directory of Open Access Journals (Sweden)

David W. Dunne

1987-01-01

Full Text Available After treatment young Kenyan schoolchildren are highly susceptible to reinfection with Schistosoma mansoni. Older children and adults are resistant to reinfection. There is no evidence that this age related resistance is due to a slow development of protective immunological mechanisms, rather, it appears that young children are susceptible because of the presence of blocking antibodies which decline with age, thus allowing the expression of protective responses. Correlations between antibody responses to different stages of the parasite life-cycle suggest that, in young children, antigen directed, isotype restriction of the response against cross-reactive polysaccharide egg antigens results in an ineffectual, or even blocking antibody response to the schistosomulum.

Multiplexed screening of natural humoral immunity identifies antibodies at fine specificity for complex and dynamic viral targets.

Science.gov (United States)

McCutcheon, Krista M; Gray, Julia; Chen, Natalie Y; Liu, Keyi; Park, Minha; Ellsworth, Stote; Tripp, Ralph A; Tompkins, S Mark; Johnson, Scott K; Samet, Shelly; Pereira, Lenore; Kauvar, Lawrence M

2014-01-01

Viral entry targets with therapeutic neutralizing potential are subject to multiple escape mechanisms, including antigenic drift, immune dominance of functionally irrelevant epitopes, and subtle variations in host cell mechanisms. A surprising finding of recent years is that potent neutralizing antibodies to viral epitopes independent of strain exist, but are poorly represented across the diverse human population. Identifying these antibodies and understanding the biology mediating the specific immune response is thus difficult. An effective strategy for meeting this challenge is to incorporate multiplexed antigen screening into a high throughput survey of the memory B cell repertoire from immune individuals. We used this approach to discover suites of cross-clade antibodies directed to conformational epitopes in the stalk region of the influenza A hemagglutinin (HA) protein and to select high-affinity anti-peptide antibodies to the glycoprotein B (gB) of human cytomegalovirus. In each case, our screens revealed a restricted VH and VL germline usage, including published and previously unidentified gene families. The in vivo evolution of paratope specificity with optimal neutralizing activity was understandable after correlating biological activities with kinetic binding and epitope recognition. Iterative feedback between antigen probe design based on structure and function information with high throughput multiplexed screening demonstrated a generally applicable strategy for efficient identification of safe, native, finely tuned antibodies with the potential for high genetic barriers to viral escape.

Hepatitis B virus reactivation during immunosuppressive therapy: Appropriate risk stratification

OpenAIRE

Seto, Wai-Kay

2015-01-01

Our understanding of hepatitis B virus (HBV) reactivation during immunosuppresive therapy has increased remarkably during recent years. HBV reactivation in hepatitis B surface antigen (HBsAg)-positive individuals has been well-described in certain immunosuppressive regimens, including therapies containing corticosteroids, anthracyclines, rituximab, antibody to tumor necrosis factor (anti-TNF) and hematopoietic stem cell transplantation (HSCT). HBV reactivation could also occur in HBsAg-negati...

Evaluation of false positivity and cross reactivity in the investigation ...

African Journals Online (AJOL)

This study evaluated the causes of false positive Human Immunodeficiency Virus test results (F+HIV), cross reactivity of HIV antibodies with other non HIV antibodies, and efficiency of the serial and parallel testing algorithms. 100 blood samples randomly collected from clients attending the Heart to Heart HIV counseling and ...

Cytomegalovirus Antibody Elevation in Bipolar Disorder: Relation to Elevated Mood States

Directory of Open Access Journals (Sweden)

A. R. Prossin

2015-01-01

Full Text Available The neurobiology of mood states is complicated by exposure to everyday stressors (e.g., psychosocial, ubiquitous environmental infections like CMV, each fluctuating between latency and reactivation. CMV reactivation induces proinflammatory cytokines (e.g., TNF-α associated with induction of neurotoxic metabolites and the presence of mood states in bipolar disorder (BD. Whether CMV reactivation is associated with bipolar diagnoses (trait or specific mood states is unclear. We investigated 139 BD type I and 99 healthy controls to determine if concentrations of IgG antibodies to Herpesviridae (e.g., CMV, HSV-1, and HSV-2 were associated with BD-I diagnosis and specific mood states. We found higher CMV antibody concentration in BD-I than in healthy controls (T234=3.1, Puncorr=0.002; Pcorr=0.006 but no difference in HSV-1 (P>0.10 or HSV-2 (P>0.10. Compared to euthymic BD-I volunteers, CMV IgG was higher in BD-I volunteers with elevated moods (P0.10. While relationships presented between BD-I diagnosis, mood states, and CMV antibodies are encouraging, they are limited by the study’s cross sectional nature. Nevertheless, further testing is warranted to replicate findings and determine whether reactivation of CMV infection exacerbates elevated mood states in BD-I.

Human antibody recognition of antigenic site IV on Pneumovirus fusion proteins.

Science.gov (United States)

Mousa, Jarrod J; Binshtein, Elad; Human, Stacey; Fong, Rachel H; Alvarado, Gabriela; Doranz, Benjamin J; Moore, Martin L; Ohi, Melanie D; Crowe, James E

2018-02-01

Respiratory syncytial virus (RSV) is a major human pathogen that infects the majority of children by two years of age. The RSV fusion (F) protein is a primary target of human antibodies, and it has several antigenic regions capable of inducing neutralizing antibodies. Antigenic site IV is preserved in both the pre-fusion and post-fusion conformations of RSV F. Antibodies to antigenic site IV have been described that bind and neutralize both RSV and human metapneumovirus (hMPV). To explore the diversity of binding modes at antigenic site IV, we generated a panel of four new human monoclonal antibodies (mAbs) and competition-binding suggested the mAbs bind at antigenic site IV. Mutagenesis experiments revealed that binding and neutralization of two mAbs (3M3 and 6F18) depended on arginine (R) residue R429. We discovered two R429-independent mAbs (17E10 and 2N6) at this site that neutralized an RSV R429A mutant strain, and one of these mAbs (17E10) neutralized both RSV and hMPV. To determine the mechanism of cross-reactivity, we performed competition-binding, recombinant protein mutagenesis, peptide binding, and electron microscopy experiments. It was determined that the human cross-reactive mAb 17E10 binds to RSV F with a binding pose similar to 101F, which may be indicative of cross-reactivity with hMPV F. The data presented provide new concepts in RSV immune recognition and vaccine design, as we describe the novel idea that binding pose may influence mAb cross-reactivity between RSV and hMPV. Characterization of the site IV epitope bound by human antibodies may inform the design of a pan-Pneumovirus vaccine.

Equine allogeneic bone marrow-derived mesenchymal stromal cells elicit antibody responses in vivo.

Science.gov (United States)

Pezzanite, Lynn M; Fortier, Lisa A; Antczak, Douglas F; Cassano, Jennifer M; Brosnahan, Margaret M; Miller, Donald; Schnabel, Lauren V

2015-04-12

This study tested the hypothesis that Major Histocompatibility Complex (MHC) incompatible equine mesenchymal stromal cells (MSCs) would induce cytotoxic antibodies to donor MHC antigens in recipient horses after intradermal injection. No studies to date have explored recipient antibody responses to allogeneic donor MSC transplantation in the horse. This information is critical because the horse is a valuable species for assessing the safety and efficacy of MSC treatment prior to human clinical application. Six MHC heterozygote horses were identified as non-ELA-A2 haplotype by microsatellite typing and used as allogeneic MHC-mismatched MSC recipients. MHC homozygote horses of known ELA-A2 haplotype were used as MSC and peripheral blood leukocyte (PBL) donors. One MHC homozygote horse of the ELA-A2 haplotype was the recipient of ELA-A2 donor MSCs as an MHC-matched control. Donor MSCs, which were previously isolated and immunophenotyped, were thawed and culture expanded to achieve between 30x10(6) and 50x10(6) cells for intradermal injection into the recipient's neck. Recipient serum was collected and tested for the presence of anti-donor antibodies prior to MSC injection and every 7 days after MSC injection for the duration of the 8-week study using the standard two-stage lymphocyte microcytotoxicity dye-exclusion test. In addition to anti-ELA-A2 antibodies, recipient serum was examined for the presence of cross-reactive antibodies including anti-ELA-A3 and anti-RBC antibodies. All MHC-mismatched recipient horses produced anti-ELA-A2 antibodies following injection of ELA-A2 MSCs and developed a wheal at the injection site that persisted for the duration of the experiment. Anti-ELA-A2 antibody responses were varied both in terms of strength and timing. Four recipient horses had high-titered anti-ELA-A2 antibody responses resulting in greater than 80% donor PBL death in the microcytotoxicity assays and one of these horses also developed antibodies that cross

Serum immunoglobulin E and immunoglobulin G reactivity to Agaricus bisporus proteins in mushroom cultivation workers.

Science.gov (United States)

Khakzad, Z; Hedayati, M T; Mahdian, S; Mayahi, S

2015-06-01

Although molds are regarded as the main fungal allergen sources, evidence indicates that spores of Basidiomycota including Agaricus bisporus ( A. bisporus ) can be also found at high concentrations in the environment and may cause as many respiratory allergies as molds. The aim of the present study was to evaluate specific immunoglobulin E (IgE) and immunoglobulin G (IgG) antibodies against A. bisporus via immunoblotting technique in individuals working at mushroom cultivation centers. In this study, 72 workers involved in the cultivation and harvest of button mushrooms were enrolled. For the analysis of serum IgE and IgG, A. bisporus grown in Sabouraud dextrose broth was harvested and ruptured by liquid nitrogen and glass beads. The obtained sample was centrifuged and the supernatant was collected as "crude extract" (CE). CE was separated via Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE). The separated proteins were transferred to a nitrocellulose filter and the bands responsive to IgE and IgG were identified by anti-human conjugated antibodies. All participants were screened in terms of total IgE level. Among 72 workers, 18 (25%) had a total IgE level higher than 188 IU/mL. In SDS-PAGE, the CE of A. bisporus showed 23 different protein bands with a molecular weight range of 13-80 kDa. The sera of 23.6% and 55.5% of participants showed positive response, with specific IgE and IgG antibodies against A. bisporus in the blot, respectively. The bands with molecular weights of 62 and 68 kDa were the most reactive protein components of A. bisporus to specific IgE antibodies. Moreover, bands with molecular weights of 57 and 62 kDa showed the highest reactivity to IgG, respectively. Also, 62 and 68 kDa components were the most reactive bands with both specific IgG and IgE antibodies. The obtained findings revealed that A. bisporus has different allergens and antigens, which contribute to its potential as an aeroallergen in hypersensitivity

Characterization of Periplasmic Protein BP26 Epitopes of Brucella melitensis Reacting with Murine Monoclonal and Sheep Antibodies

Science.gov (United States)

Wu, Jingbo; Zhang, Hui; Wang, Yuanzhi; Qiao, Jun; Chen, Chuangfu; Gao, Goege F.; Allain, Jean-Pierre; Li, Chengyao

2012-01-01

More than 35,000 new cases of human brucellosis were reported in 2010 by the Chinese Center for Disease Control and Prevention. An attenuated B. melitensis vaccine M5-90 is currently used for vaccination of sheep and goats in China. In the study, a periplasmic protein BP26 from M5-90 was characterized for its epitope reactivity with mouse monoclonal and sheep antibodies. A total of 29 monoclonal antibodies (mAbs) against recombinant BP26 (rBP26) were produced, which were tested for reactivity with a panel of BP26 peptides, three truncated rBP26 and native BP26 containing membrane protein extracts (NMP) of B. melitensis M5-90 in ELISA and Western-Blot. The linear, semi-conformational and conformational epitopes from native BP26 were identified. Two linear epitopes recognized by mAbs were revealed by 28 of 16mer overlapping peptides, which were accurately mapped as the core motif of amino acid residues 93DRDLQTGGI101 (position 93 to 101) or residues 104QPIYVYPD111, respectively. The reactivity of linear epitope peptides, rBP26 and NMP was tested with 137 sheep sera by ELISAs, of which the two linear epitopes had 65–70% reactivity and NMP 90% consistent with the results of a combination of two standard serological tests. The results were helpful for evaluating the reactivity of BP26 antigen in M5-90. PMID:22457830

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

Directory of Open Access Journals (Sweden)

Elissa J. Schwartz

2014-05-01

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

Antibodies against deamidated gliadin peptides identify adult coeliac disease patients negative for antibodies against endomysium and tissue transglutaminase.

Science.gov (United States)

Dahle, C; Hagman, A; Ignatova, S; Ström, M

2010-07-01

This study was done to evaluate the diagnostic utility of antibodies against deamidated gliadin peptides compared to traditional markers for coeliac disease. To evaluate diagnostic utility of antibodies against deamidated gliadin peptide (DGP). Sera from 176 adults, referred for endoscopy without previous analysis of antibodies against tissue transglutaminase (tTG) or endomysium (EmA), were retrospectively analysed by ELISAs detecting IgA/IgG antibodies against DGP or a mixture of DGP and tTG, and compared with IgA-tTG and EmA. Seventy-nine individuals were diagnosed with coeliac disease. Receiver operating characteristic analyses verified the manufacturers' cut-off limits except for IgA/IgG-DGP/tTG. In sera without IgA deficiency, the sensitivity was higher for IgA/IgG-DGP (0.85-0.87) compared with IgA-tTg (0.76) and EmA (0.61). All tests showed high specificity (0.95-1.00). Eighteen coeliac disease-sera were negative regarding IgA-tTG, nine of which were positive for IgA/IgG-DGP. Sera from coeliac disease-patients >70 years were more often negative for IgA-tTG (50%) and IgA/IgG-DGP (36%) than younger patients (15% and 8% respectively) (P adult coeliac disease patients negative for antibodies against endomysium and tissue transglutaminase. Serology is often negative in elderly patients with coeliac disease; a small bowel biopsy should therefore be performed generously before coeliac disease is excluded.

Identification of antigen-specific human monoclonal antibodies using high-throughput sequencing of the antibody repertoire.

Science.gov (United States)

Liu, Ju; Li, Ruihua; Liu, Kun; Li, Liangliang; Zai, Xiaodong; Chi, Xiangyang; Fu, Ling; Xu, Junjie; Chen, Wei

2016-04-22

High-throughput sequencing of the antibody repertoire provides a large number of antibody variable region sequences that can be used to generate human monoclonal antibodies. However, current screening methods for identifying antigen-specific antibodies are inefficient. In the present study, we developed an antibody clone screening strategy based on clone dynamics and relative frequency, and used it to identify antigen-specific human monoclonal antibodies. Enzyme-linked immunosorbent assay showed that at least 52% of putative positive immunoglobulin heavy chains composed antigen-specific antibodies. Combining information on dynamics and relative frequency improved identification of positive clones and elimination of negative clones. and increase the credibility of putative positive clones. Therefore the screening strategy could simplify the subsequent experimental screening and may facilitate the generation of antigen-specific antibodies. Copyright © 2016 Elsevier Inc. All rights reserved.

Advantages of Papio anubis for preclinical testing of immunotoxicity of candidate therapeutic antagonist antibodies targeting CD28

Science.gov (United States)

Poirier, Nicolas; Mary, Caroline; Le Bas-Bernardet, Stephanie; Daguin, Veronique; Belarif, Lyssia; Chevalier, Melanie; Hervouet, Jeremy; Minault, David; Ville, Simon; Charpy, Vianney; Blancho, Gilles; Vanhove, Bernard

2014-01-01

Antagonist anti-CD28 antibodies prevent T-cell costimulation and are functionally different from CTLA4Ig since they cannot block CTLA-4 and PDL-1 co-inhibitory signals. They demonstrated preclinical efficacy in suppressing effector T cells while enhancing immunoregulatory mechanisms. Because a severe cytokine release syndrome was observed during the Phase 1 study with the superagonist anti-CD28 TGN1412, development of other anti-CD28 antibodies requires careful preclinical evaluation to exclude any potential immunotoxicity side-effects. The failure to identify immunological toxicity of TGN1412 using macaques led us to investigate more relevant preclinical models. We report here that contrary to macaques, and like in man, all baboon CD4-positive T lymphocytes express CD28 in their effector memory cells compartment, a lymphocyte subtype that is the most prone to releasing cytokines after reactivation. Baboon lymphocytes are able to release pro-inflammatory cytokines in vitro in response to agonist or superagonist anti-CD28 antibodies. Furthermore, we compared the reactivity of human and baboon lymphocytes after transfer into non obese diabetic/severe combined immunodeficiency (NOD/SCID) interleukin-2rγ knockout mice and confirmed that both cell types could release inflammatory cytokines in situ after injection of agonistic anti-CD28 antibodies. In contrast, FR104, a monovalent antagonistic anti-CD28 antibody, did not elicit T cell activation in these assays, even in the presence of anti-drug antibodies. Infusion to baboons also resulted in an absence of cytokine release. In conclusion, the baboon represents a suitable species for preclinical immunotoxicity evaluation of anti-CD28 antibodies because their effector memory T cells do express CD28 and because cytokine release can be assessed in vitro and trans vivo. PMID:24598534

Human Cytomegalovirus Infection Increases Both Antibody- and Non–Antibody-Dependent Cellular Reactivity by Natural Killer Cells

Directory of Open Access Journals (Sweden)

Clive M. Michelo, PhD

2017-12-01

Conclusions. With regard to organ transplantation, these data suggest that CMV infection enhances NK cell alloreactivity, which may pose an additional adverse effect on graft survival, especially in the presence of donor specific antibodies.

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

Directory of Open Access Journals (Sweden)

Spiropoulou Christina F

2010-06-01

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

The detection of ovarian cancer using 123I monoclonal antibody

International Nuclear Information System (INIS)

Granowska, M.; Britton, K.E.; Shepherd, J.

1984-01-01

The technique of the production of monoclonal antibodies is described. Antibodies show reactivity with epithelial surfaces of cancer of breast, colon and ovary. The iodogen reaction is used for labelling monoclonal antibodies with 123 I. Description of labelling technique and quality control. After intravenous injection of 74 MBq 123 I-labelled monoclonal antibody (0.5 mg) static camera images of the abdomen were recorded at 10 min, 4 and 22 hours in anterior and posterior position. 20 out of 22 patients with ovarian cancer with and without metastases were correctly diagnosed and confirmed at surgery. (author)

Targeting a Cross-Reactive Gly m 5 Soy Peptide as Responsible for Hypersensitivity Reactions in a Milk Allergy Mouse Model

Science.gov (United States)

Curciarello, Renata; Smaldini, Paola L.; Candreva, Angela M.; González, Virginia; Parisi, Gustavo; Cauerhff, Ana; Barrios, Ivana; Blanch, Luis Bruno; Fossati, Carlos A.

2014-01-01

Background Cross-reactivity between soybean allergens and bovine caseins has been previously reported. In this study we aimed to map epitopes of the major soybean allergen Gly m 5 that are co-recognized by casein specific antibodies, and to identify a peptide responsible for the cross-reactivity. Methods Cow's milk protein (CMP)-specific antibodies were used in different immunoassays (immunoblotting, ELISA, ELISA inhibition test) to evaluate the in vitro recognition of soybean proteins (SP). Recombinant Gly m 5 (α), a truncated fragment containing the C-terminal domain (α-T) and peptides of α-T were obtained and epitope mapping was performed with an overlapping peptide assay. Bioinformatics tools were used for epitope prediction by sequence alignment, and for modelling the cross-recognized soy proteins and peptides. The binding of SP to a monoclonal antibody was studied by surface Plasmon resonance (SPR). Finally, the in vivo cross-recognition of SP was assessed in a mouse model of milk allergy. Results Both α and α-T reacted with the different CMP-specific antibodies. α-T contains IgG and IgE epitopes in several peptides, particularly in the peptide named PA. Besides, we found similar values of association and dissociation constants between the α-casein specific mAb and the different milk and soy components. The food allergy mouse model showed that SP and PA contain the cross-reactive B and T epitopes, which triggered hypersensitivity reactions and a Th2-mediated response on CMP-sensitized mice. Conclusions Gly m 5 is a cross-reactive soy allergen and the α-T portion of the molecule contains IgG and IgE immunodominant epitopes, confined to PA, a region with enough conformation to be bound by antibodies. These findings contribute to explain the intolerance to SP observed in IgE-mediated CMA patients, primarily not sensitised to SP, as well as it sets the basis to propose a mucosal immunotherapy for milk allergy using this soy peptide. PMID:24416141

Fully human monoclonal antibodies from antibody secreting cells after vaccination with Pneumovax®23 are serotype specific and facilitate opsonophagocytosis.

Science.gov (United States)

Smith, Kenneth; Muther, Jennifer J; Duke, Angie L; McKee, Emily; Zheng, Nai-Ying; Wilson, Patrick C; James, Judith A

2013-05-01

B lymphocyte memory generates antibody-secreting cells (ASCs) that represent a source of protective antibodies that may be exploited for therapeutics. Here we vaccinated four donors with Pneumovax®23 and produced human monoclonal antibodies (hmAbs) from ASCs. We have cloned 137 hmAbs and the specificities of these antibodies encompass 19 of the 23 serotypes in the vaccine, as well as cell wall polysaccharide (CWPS). Although the majority of the antibodies are serotype specific, 12% cross-react with two serotypes. The Pneumovax®23 ASC antibody sequences are highly mutated and clonal, indicating an anamnestic response, even though this was a primary vaccination. Hmabs from 64% of the clonal families facilitate opsonophagocytosis. Although 9% of the total antibodies bind to CWPS impurity in the vaccine, none of these clonal families showed opsonophagocytic activity. Overall, these studies have allowed us to address unanswered questions in the field of human immune responses to polysaccharide vaccines, including the cross-reactivity of individual antibodies between serotypes and the percentage of antibodies that are protective after vaccination with Pneumovax®23. Copyright © 2012 Elsevier GmbH. All rights reserved.

The self-nonself discrimination and the nature and acquisition of the antibody repertoire.

Science.gov (United States)

Coutinho, A

1980-01-01

Network ideas are confronted with current hypotheses for the origin of antibody diversity and self-nonself discrimination. The difficulties of reconciling the promethean evolution of the antibody system with "germ line" theories are discussed, as well as the problems of "somatic" hypotheses to explain the completeness of the antibody repertoire. The formal incompatibility of the network theory with ideas basing self-nonself discrimination on the elimination of self-reactive cells is demonstrated, as well as the difficulties of these and other environment-dependent hypotheses for lymphocyte activation, to encompass the internal activity in the immune system. It is argued, on the other hand, that the limitations of the network theory in providing a functional basis for the idiotypic network and in accounting for self-nonself discrimination, can be solved by finding in a complete repertoire of antibody-combining sites the complementary structures to growth receptors on B lymphocytes, and by using these as internal mitogens in the expansion of the precursor cell pools and in the maintenance of the mature steady states. Letting self-nonself discrimination be accounted for by such growth receptors, both the integrity of the antibody repertoire and the internal activity in the system can also be ensured. Moreover, by postulating a germ line origin for the antireceptor antibodies and by accepting idiotypic cross-reactivity between growth receptors and other germ line antibodies, the possibilities are set for a phylogenetically and ontogenically autonomous immune system embodied with the capabilities for self-expansion, diversification and selection of available repertoires. Its promethean characteristics are explained by its completeness, and this is achieved by idiotypic interactions between growth receptors and a limited number of complementary or cross-reactive germ line antibodies, naturally selected on the basis of their structural relationships with growth receptors.

Probable C4d-negative accelerated acute antibody-mediated rejection due to non-HLA antibodies.

Science.gov (United States)

Niikura, Takahito; Yamamoto, Izumi; Nakada, Yasuyuki; Kamejima, Sahoko; Katsumata, Haruki; Yamakawa, Takafumi; Furuya, Maiko; Mafune, Aki; Kobayashi, Akimitsu; Tanno, Yudo; Miki, Jun; Yamada, Hiroki; Ohkido, Ichiro; Tsuboi, Nobuo; Yamamoto, Hiroyasu; Yokoo, Takashi

2015-07-01

We report a case of probable C4d-negative accelerated acute antibody-mediated rejection due to non-HLA antibodies. A 44 year-old male was admitted to our hospital for a kidney transplant. The donor, his wife, was an ABO minor mismatch (blood type O to A) and had Gitelman syndrome. Graft function was delayed; his serum creatinine level was 10.1 mg/dL at 3 days after transplantation. Open biopsy was performed immediately; no venous thrombosis was observed during surgery. Histology revealed moderate peritubular capillaritis and mild glomerulitis without C4d immunoreactivity. Flow cytometric crossmatching was positive, but no panel-reactive antibodies against HLA or donor-specific antibodies (DSAbs) to major histocompatibility complex class I-related chain A (MICA) were detected. Taken together, we diagnosed him with probable C4d-negative accelerated antibody-mediated rejection due to non-HLA, non-MICA antibodies, the patient was treated with steroid pulse therapy (methylprednisolone 500 mg/day for 3 days), plasma exchange, intravenous immunoglobulin (40 g/body), and rituximab (200 mg/body) were performed. Biopsy at 58 days after transplantation, at which time S-Cr levels were 1.56 mg/dL, found no evidence of rejection. This case, presented with a review of relevant literature, demonstrates that probable C4d-negative accelerated acute AMR can result from non-HLA antibodies. © 2015 Asian Pacific Society of Nephrology.

Anti-human immunodeficiency virus-1 antibody titers in injection drug users compared to sexually infected individuals.

Science.gov (United States)

Bongertz, Vera; Ouverney, Elaine Priscilla; Teixeira, Sylvia L M; Silva-de-Jesus, Carlos; Hacker, Mariana A; Morgado, Mariza G; Bastos, Francisco I

2003-03-01

Sera from infected injection drug users (IDU) have shown to have antibodies against synthetic human immunodeficiency virus-1 (HIV-1) envelope peptides more frequently. In this study, reactivity of 48 IDU plasma were compared to 60 plasmas obtained from sexually infected individuals (S). The overall reactivity of plasma from IDU compared to S was higher, and the reactivity titers were much higher for IDU plasma than S. IDU plasma also showed a broader antibody response. The higher reactivity titers were observed mainly for the gp41 immunodominant epitope and V3 peptides corresponding to the consensus sequences of HIV-1 subtypes/variants prevalent in Brazil (B, F, C) indicating the specificity in the higher immune response of IDU.

Association of Distinct Fine Specificities of Anti-Citrullinated Peptide Antibodies With Elevated Immune Responses to Prevotella intermedia in a Subgroup of Patients With Rheumatoid Arthritis and Periodontitis.

Science.gov (United States)

Schwenzer, Anja; Quirke, Anne-Marie; Marzeda, Anna M; Wong, Alicia; Montgomery, Anna B; Sayles, Harlan R; Eick, Sigrun; Gawron, Katarzyna; Chomyszyn-Gajewska, Maria; Łazarz-Bartyzel, Katarzyna; Davis, Simon; Potempa, Jan; Kessler, Benedikt M; Fischer, Roman; Venables, Patrick J; Payne, Jeffrey B; Mikuls, Ted R; Midwood, Kim S

2017-12-01

In addition to the long-established link with smoking, periodontitis (PD) is a risk factor for rheumatoid arthritis (RA). This study was undertaken to elucidate the mechanism by which PD could induce antibodies to citrullinated peptides (ACPAs), by examining the antibody response to a novel citrullinated peptide of cytokeratin 13 (CK-13) identified in gingival crevicular fluid (GCF), and comparing the response to 4 other citrullinated peptides in patients with RA who were well-characterized for PD and smoking. The citrullinomes of GCF and periodontal tissue from patients with PD were mapped by mass spectrometry. ACPAs of CK13 (cCK13), tenascin-C (cTNC5), vimentin (cVIM), α-enolase (CEP-1), and fibrinogen β (cFIBβ) were examined by enzyme-linked immunosorbent assay in patients with RA (n = 287) and patients with osteoarthritis (n = 330), and cross-reactivity was assessed by inhibition assays. A novel citrullinated peptide cCK13-1 ( 444 TSNASGR-Cit-TSDV-Cit-RP 458 ) identified in GCF exhibited elevated antibody responses in RA patients (24%). Anti-cCK13-1 antibody levels correlated with anti-cTNC5 antibody levels, and absorption experiments confirmed this was not due to cross-reactivity. Only anti-cCK13-1 and anti-cTNC5 were associated with antibodies to the periodontal pathogen Prevotella intermedia (P = 0.05 and P = 0.001, respectively), but not with antibodies to Porphyromonas gingivalis arginine gingipains. Levels of antibodies to CEP-1, cFIBβ, and cVIM correlated with each other, and with smoking and shared epitope risk factors in RA. This study identifies 2 groups of ACPA fine specificities associated with different RA risk factors. One is predominantly linked to smoking and shared epitope, and the other links anti-cTNC5 and cCK13-1 to infection with the periodontal pathogen P intermedia. © 2017 The Authors. Arthritis & Rheumatology published by Wiley Periodicals, Inc. on behalf of American College of Rheumatology.

Allergic cross-reactivity – anew challenge for allergists?

Directory of Open Access Journals (Sweden)

Krzysztof Łukasz Piwowarek

2015-12-01

Full Text Available Allergic cross-reactivity is an important epidemiological issue in all age groups. It is caused by a non-specific binding of both primary allergen as well as allergens causing secondary cross-reactivity by the same IgE antibodies. This phenomenon results from the similarity of the molecular structure of allergen epitopes and leads to a number of allergic cross-reactivity syndromes, such as pollen-food syndromes, pork-cat syndrome or latex-fruit syndrome. They are characterized by rich symptomatology and the possible occurrence of symptoms related to various systems, including life-threatening systemic reactions. In many cases, specific allergen groups responsible for certain cross-reactions, such as plant profilins, fish parvalbumins or invertebrate tropomyosins, have been identified. Also, some of the factors affecting the spatial conformation of allergens, and thus modifying their allergenic potential, have been identified. Despite all these achievements, the diagnostics of cross reactivity syndromes still remains difficult due to the limited available methods and the possible occurrence of overlapping phenomena such as co-sensitisation, asymptomatic cross-sensitisation or IgE-independent or nonimmunological adverse drug reactions. Therefore, careful management based on medical history as well as avoidance of unjustified treatment methods, e.g. diet therapy or immunotherapy, are necessary. This is of great importance as the incidence of food allergies is expected to increase mainly due to the progressive rise in the prevalence of inhalant allergies to pollens.

Antibody profiling sensitivity through increased reporter antibody layering

Science.gov (United States)

Apel, William A; Thompson, Vicki S

2013-02-26

A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immune complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source. Further, an assay, such as a test for illegal drug use, can be coupled to a test for identity such that the results of the assay can be positively correlated to the subject's identity.

Antibody profiling sensitivity through increased reporter antibody layering

Energy Technology Data Exchange (ETDEWEB)

Apel, William A.; Thompson, Vicki S.

2017-03-28

A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immune complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source. Further, an assay, such as a test for illegal drug use, can be coupled to a test for identity such that the results of the assay can be positively correlated to the subject's identity.

Antibody profiling sensitivity through increased reporter antibody layering

Energy Technology Data Exchange (ETDEWEB)

Apel, William A.; Thompson, Vicki S.

2013-02-26

A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immune complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source. Further, an assay, such as a test for illegal drug use, can be coupled to a test for identity such that the results of the assay can be positively correlated to the subject's identity.

Antibody profiling sensitivity through increased reporter antibody layering

Energy Technology Data Exchange (ETDEWEB)

Apel, William A.; Thompson, Vicki S

2010-04-13

A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immune complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source. Further, an assay, such as a test for illegal drug use, can be coupled to a test for identity such that the results of the assay can be positively correlated to the subject's identity.

Diversity of the murine antibody response targeting influenza A(H1N1pdm09) hemagglutinin.

Science.gov (United States)

Wilson, Jason R; Tzeng, Wen-Pin; Spesock, April; Music, Nedzad; Guo, Zhu; Barrington, Robert; Stevens, James; Donis, Ruben O; Katz, Jacqueline M; York, Ian A

2014-06-01

We infected mice with the 2009 influenza A pandemic virus (H1N1pdm09), boosted with an inactivated vaccine, and cloned immunoglobulins (Igs) from HA-specific B cells. Based on the redundancy in germline gene utilization, we inferred that between 72-130 unique IgH VDJ and 35 different IgL VJ combinations comprised the anti-HA recall response. The IgH VH1 and IgL VK14 variable gene families were employed most frequently. A representative panel of antibodies were cloned and expressed to confirm reactivity with H1N1pdm09 HA. The majority of the recombinant antibodies were of high avidity and capable of inhibiting H1N1pdm09 hemagglutination. Three of these antibodies were subtype-specific cross-reactive, binding to the HA of A/South Carolina/1/1918(H1N1), and one further reacted with A/swine/Iowa/15/1930(H1N1). These results help to define the genetic diversity of the influenza anti-HA antibody repertoire profile induced following infection and vaccination, which may facilitate the development of influenza vaccines that are more protective and broadly neutralizing. Protection against influenza viruses is mediated mainly by antibodies, and in most cases this antibody response is narrow, only providing protection against closely related viruses. In spite of this limited range of protection, recent findings indicate that individuals immune to one influenza virus may contain antibodies (generally a minority of the overall response) that are more broadly reactive. These findings have raised the possibility that influenza vaccines could induce a more broadly protective response, reducing the need for frequent vaccine strain changes. However, interpretation of these observations is hampered by the lack of quantitative characterization of the antibody repertoire. In this study, we used single-cell cloning of influenza HA-specific B cells to assess the diversity and nature of the antibody response to influenza hemagglutinin in mice. Our findings help to put bounds on the

Prevalence and chemotherapy-induced reactivation of occult hepatitis B virus among hepatitis B surface antigen negative patients with diffuse large B-cell lymphoma: Significance of hepatitis B core antibodies screening

International Nuclear Information System (INIS)

Elbedewy, T.A.; Elashtokhy, H.A.; Rabee, E.S.; Kheder, G.E.

2015-01-01

Background: Occult hepatitis B infection (OBI) is characterized by negative hepatitis B surface antigen (HBsAg) and detectable hepatitis B virus (HBV)-DNA in the liver and/or serum, with or without hepatitis B core antibody (anti-HBc). Anti-HBc is the most sensitive marker of previous HBV. HBV reactivation in patients under immunosuppressive treatment is life-threatening, occurring in both overt and occult HBV especially in hematological malignancies. Aim of the work: To evaluate the prevalence and chemotherapy-induced reactivation of OBI among hepatitis B surface antigen negative patients with diffuse large B-cell lymphoma (DLBCL) patients and to determine the significance of anti-HBc screening among this group of patients before receiving chemotherapy. Patients and methods: This cross-sectional study included 72 DLBCL patients negative for HBsAg, HBsAb and hepatitis C virus antibodies (anti-HCV). Patients were subjected to investigations including anti-HBc. All patients underwent alanine transaminase (ALT) monitoring before each cycle of chemotherapy and monthly for 12 months after the end of chemotherapy. Patients with suspected OBI were tested for HBV-DNA using real-time polymerase chain reaction (PCR). Results: Anti-HBc was detected in 10 of 72 HBsAg negative sera (13.89%) (95% confidence interval 6.9-22.2%). Five of the 10 anti-HBc positive patients in this study had OBI reactivation. Conclusion: The study concluded that anti-HBc screening is mandatory before chemotherapy. HBsAg-negative/anti-HBc-positive patients should be closely observed for signs of HBV reactivation through the regular monitoring of ALT. Prophylaxis lamivudine is recommended for anti-HBc positive patients before chemotherapy.

IgG subclass reactivity to Trypanosoma cruzi in chronic chagasic patients.

Science.gov (United States)

Hernández-Becerril, N; Nava, A; Reyes, P A; Monteón, V M

2001-01-01

The anti-Trypanosoma cruzi antibodies isotype profile in Chagas' disease has been studied in relation to different clinical manifestations. A high titer of IgG anti-T. cruzi antibodies is found in patients with cardiac involvement, while a high titer of IgA anti-T. cruzi antibodies is associated with digestive forms. The aim of this work was to analyze the IgG subclass reactivity of anti-T. cruzi antibodies in patients with chronic Chagasic cardiomyopathy. Twelve consecutive chagasic patients were analyzed for IgG subclass reactivity to a T. cruzi antigenic extract. They had a complete clinical evaluation, peripheral EKG, echocardiography, left ventriculogram, and coronariography. All patients came from rural areas of Mexico and had lived in endemic zones for over seven years. They presented left ventricular endsystolic dimension above 42 mm in 58% (7/12) and ejection fraction below 50% in 58% (7/12). We found that IgG1 and IgG2 anti-T. cruzi antibodies showed higher titer than IgG3 antibodies, with consistently low titer of IgG4 antibodies. Expression of the four IgG subclasses of anti-T. cruzi antibodies suggest a mixed Th1/Th2-like immune response under a probably continuous chronic antigenic stimulation. On the other hand, high levels of IgG2 anti-T. cruzi antibodies showed a tendency to be associated with severe cardiomegaly. Our results suggest that a mixed Th1/Th2-like immune response may take place in chronic chagasic patients under a chronic antigenic stimulation.

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

Directory of Open Access Journals (Sweden)

Gabriele Gadermaier

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

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

Science.gov (United States)

Gadermaier, Gabriele; Hauser, Michael; Egger, Matthias; Ferrara, Rosetta; Briza, Peter; Santos, Keity Souza; Zennaro, Danila; Girbl, Tamara; Zuidmeer-Jongejan, Laurian; Mari, Adriano; Ferreira, Fatima

2011-01-01

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

Dengue virus infection induces broadly cross-reactive human IgM antibodies that recognize intact virions in humanized BLT-NSG mice.

Science.gov (United States)

Jaiswal, Smita; Smith, Kenneth; Ramirez, Alejandro; Woda, Marcia; Pazoles, Pamela; Shultz, Leonard D; Greiner, Dale L; Brehm, Michael A; Mathew, Anuja

2015-01-01

The development of small animal models that elicit human immune responses to dengue virus (DENV) is important since prior immunity is a major risk factor for developing severe dengue disease. This study evaluated anti-DENV human antibody (hAb) responses generated from immortalized B cells after DENV-2 infection in NOD-scid IL2rγ(null) mice that were co-transplanted with human fetal thymus and liver tissues (BLT-NSG mice). DENV-specific human antibodies predominantly of the IgM isotype were isolated during acute infection and in convalescence. We found that while a few hAbs recognized the envelope protein produced as a soluble recombinant, a number of hAbs only recognized epitopes on intact virions. The majority of the hAbs isolated during acute infection and in immune mice were serotype-cross-reactive and poorly neutralizing. Viral titers in immune BLT-NSG mice were significantly decreased after challenge with a clinical strain of dengue. DENV-specific hAbs generated in BLT-NSG mice share some of the characteristics of Abs isolated in humans with natural infection. Humanized BLT-NSG mice provide an attractive preclinical platform to assess the immunogenicity of candidate dengue vaccines. © 2014 by the Society for Experimental Biology and Medicine.

Meta-analysis reveals an association of STAT4 polymorphisms with systemic autoimmune disorders and anti-dsDNA antibody.

Science.gov (United States)

Zheng, Junfeng; Yin, Junping; Huang, Renliang; Petersen, Frank; Yu, Xinhua

2013-08-01

Signal transducer and activator of transcription 4 (STAT4) has been recently identified as a susceptibility gene for multiple autoimmune diseases. Here we performed a comprehensive analysis of the association between STAT4 and several different autoimmune disorders to identify potential common inflammatory principles behind this association. Our meta-analysis revealed that the STAT4 rs7574865 polymorphism is associated with four autoimmune diseases with systemic pathology, including systemic lupus erythematosus (OR = 1.52; 95% CI = 1.48 - 1.56, Prs7574865 polymorphism is associated with the presence of autoantibodies with systemic reactivity (anti-ds-DNA antibodies) in SLE patients (OR = 1.37; 95% CI = 1.21 - 1.56, P = 1.12 × 10(-6)). However, no such specific association was seen in RA with regard to the presence of non-systemically reacting antibodies, including rheumatoid factor and anti-cyclic citrullinated peptide antibodies. Taken together, these results suggest that STAT4 polymorphisms are associated with autoimmune diseases which are characterized by a systemic pathology and anti-dsDNA antibody. Copyright © 2013 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Monoclonal antibodies for treating cancer

International Nuclear Information System (INIS)

Dillman, R.O.

1989-01-01

The purpose of this study is to assess the current status of in-vivo use of monoclonal antibodies for treating cancer. Publications appearing between 1980 and 1988 were identified by computer searches using MEDLINE and CANCERLIT, by reviewing the table of contents of recently published journals, and by searching bibliographies of identified books and articles. More than 700 articles, including peer-reviewed articles and book chapters, were identified and selected for analysis. The literature was reviewed and 235 articles were selected as relevant and representative of the current issues and future applications for in-vivo monoclonal antibodies for cancer therapy and of the toxicity and efficacy which has been associated with clinical trials. Approaches include using antibody alone (interacting with complement or effector cells or binding directly with certain cell receptors) and immunoconjugates (antibody coupled to radioisotopes, drugs, toxins, or other biologicals). Most experience has been with murine antibodies. Trials of antibody alone and radiolabeled antibodies have confirmed the feasibility of this approach and the in-vivo trafficking of antibodies to tumor cells. However, tumor cell heterogeneity, lack of cytotoxicity, and the development of human antimouse antibodies have limited clinical efficacy. Although the immunoconjugates are very promising, heterogeneity and the antimouse immune response have hampered this approach as has the additional challenge of chemically or genetically coupling antibody to cytotoxic agents. As a therapeutic modality, monoclonal antibodies are still promising but their general use will be delayed for several years. New approaches using human antibodies and reducing the human antiglobulin response should facilitate treatment. 235 references

Lyssavirus-reactive antibodies in Swedish bats

Directory of Open Access Journals (Sweden)

Anna-Lena Hammarin

2016-12-01

Full Text Available Introduction: To study the presence of European bat lyssavirus (EBLV infections in bat reservoirs in Sweden, active surveillance was performed during the summers from 2008 to 2013. Material and methods: Bat specimens were collected at >20 bat colonies in the central, southeastern, and southern parts of Sweden. In total, blood and saliva of 452 bats were examined by a virus neutralization test and by reverse transcription polymerase chain reactions (RT-PCRs. Results and discussion: EBLV neutralizing antibodies were detected in 14 Daubenton's bats (Myotis daubentonii, all trapped in Skåne or Småland (south and southeast of Sweden. The result was not unexpected since EBLV has been shown to be present in many neighboring countries, for example, Denmark, Finland, Germany, and Norway. However, Sweden has been regarded free of rabies in terrestrial mammals since 1896. Although very rare, spillover of EBLV into other animals and humans have occurred, and the risk of EBLV infection to other species including humans should not be ignored. This is the first report of lyssavirus infection in Swedish bats.

C4d-negative antibody-mediated rejection with high anti-angiotensin II type I receptor antibodies in absence of donor-specific antibodies.

Science.gov (United States)

Fuss, Alexander; Hope, Christopher M; Deayton, Susan; Bennett, Greg Donald; Holdsworth, Rhonda; Carroll, Robert P; Coates, P Toby H

2015-07-01

Acute antibody-mediated rejection can occur in absence of circulating donor-specific antibodies. Agonistic antibodies targeting the anti-angiotensin II type 1 receptor (anti-AT1 R) are emerging as important non-human leucocyte antigen (HLA) antibodies. Elevated levels of anti-angiotensin II receptor antibodies were first observed in kidney transplant recipients with malignant hypertension and allograft rejection. They have now been studied in three separate kidney transplant populations and associate to frequency of rejection, severity of rejection and graft failure. We report 11 cases of biopsy-proven, Complement 4 fragment d (C4d)-negative, acute rejection occurring without circulating donor-specific anti-HLA antibodies. In eight cases, anti-angiotensin receptor antibodies were retrospectively examined. The remaining three subjects were identified from our centre's newly instituted routine anti-angiotensin receptor antibody screening. All subjects fulfilled Banff 2013 criteria for antibody-mediated rejection and all responded to anti-rejection therapy, which included plasma exchange and angiotensin receptor blocker therapy. These cases support the routine assessment of anti-AT1 R antibodies in kidney transplant recipients to identify subjects at risk. Further studies will need to determine optimal assessment protocol and the effectiveness of pre-emptive treatment with angiotensin receptor blockers. © 2015 Asian Pacific Society of Nephrology.

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

Directory of Open Access Journals (Sweden)

Kai Xu

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

Anti-HmuY antibodies specifically recognize Porphyromonas gingivalis HmuY protein but not homologous proteins in other periodontopathogens.

Directory of Open Access Journals (Sweden)

Michał Śmiga

Full Text Available Given the emerging evidence of an association between periodontal infections and systemic conditions, the search for specific methods to detect the presence of P. gingivalis, a principal etiologic agent in chronic periodontitis, is of high importance. The aim of this study was to characterize antibodies raised against purified P. gingivalis HmuY protein and selected epitopes of the HmuY molecule. Since other periodontopathogens produce homologs of HmuY, we also aimed to characterize responses of antibodies raised against the HmuY protein or its epitopes to the closest homologous proteins from Prevotella intermedia and Tannerella forsythia. Rabbits were immunized with purified HmuY protein or three synthetic, KLH-conjugated peptides, derived from the P. gingivalis HmuY protein. The reactivity of anti-HmuY antibodies with purified proteins or bacteria was determined using Western blotting and ELISA assay. First, we found homologs of P. gingivalis HmuY in P. intermedia (PinO and PinA proteins and T. forsythia (Tfo protein and identified corrected nucleotide and amino acid sequences of Tfo. All proteins were overexpressed in E. coli and purified using ion-exchange chromatography, hydrophobic chromatography and gel filtration. We demonstrated that antibodies raised against P. gingivalis HmuY are highly specific to purified HmuY protein and HmuY attached to P. gingivalis cells. No reactivity between P. intermedia and T. forsythia or between purified HmuY homologs from these bacteria and anti-HmuY antibodies was detected. The results obtained in this study demonstrate that P. gingivalis HmuY protein may serve as an antigen for specific determination of serum antibodies raised against this bacterium.

A sensitive radioimmunoassay for the detection of monoclonal anti-idiotype antibodies

International Nuclear Information System (INIS)

Morahan, G.

1983-01-01

A radioimmunoassay was developed in order to detect anti-idiotypic antibodies in the supernatants of hybrid cells. This assay is both sensitive and specific for anti-idiotypic (but not anti-allotypic) antibodies. Monoclonal antibodies present in test supernatants are bound by an anti-immunoglobulin coated solid phase. Subsequent incubation with a source of mouse immunoglobulin 'blocks' unreacted anti-immunoglobulin antibodies on the solid phase. Anti-idiotypic antibodies are then detected by their ability to bind 125 I-labelled idiotype-bearing antibody. This paper describes the use of this assay to detect monoclonal anti-idiotypic antibodies in 2 systems; the cross-reactive idiotype of A/J anti-ABA antibodies, and the idiotype expressed by the myeloma protein HOPC 8. Similarly, 125 I-labelled anti-idiotype antibodies may be used in this assay to detect monoclonal idiotype-bearing antibodies. Further modifications are described which would allow the detection of monoclonal anti-allotype antibodies. (Auth.)

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

OpenAIRE

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

2008-01-01

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

Immunochemical and biological properties of a mouse monoclonal antibody reactive to prunus necrotic ringspot ilarvirus.

Science.gov (United States)

Aebig, J A; Jordan, R L; Lawson, R H; Hsu, H T

1987-01-01

A monoclonal antibody reacting with prunus necrotic ringspot ilarvirus was tested in immunochemical studies, neutralization of infectivity assays, and by immuno-electron microscopy. The antibody was able to detect the 27,000 Mr coat protein of prunus necrotic ringspot ilarvirus in western blots and also detected all polypeptide fragments generated after incubation of whole virus with proteolytic enzymes. In neutralization of infectivity studies, the antibody blocked virus infectivity, although it did not precipitate the antigen in agar gel Ouchterlony double diffusion tests. Immuno-electron microscopy confirmed that the antibody coats virions but does not cause clumping. The antibody may be a useful tool for investigating coat protein-dependent initiation of ilarvirus infection.

Antibody Profile of Colostrum and the Effect of Processing in Human Milk Banks: Implications in Immunoregulatory Properties.

Science.gov (United States)

Rodríguez-Camejo, Claudio; Puyol, Arturo; Fazio, Laura; Rodríguez, Analía; Villamil, Emilia; Andina, Eliana; Cordobez, Vanira; Díaz, Hernán; Lemos, Mary; Siré, Gabriela; Carroscia, Lilián; Castro, Mara; Panizzolo, Luis; Hernández, Ana

2018-02-01

When feeding preterm infants, donor milk is preferred if the mother's own milk is unavailable. Pasteurization may have detrimental effects on bioactivity, but more information is needed about its effects on the immunological compounds. Research aim: This work has two main aims: evaluate the antibody profile of colostrum and study the quantitative variations in the antibodies' level and specific reactivity after undergoing Holder pasteurization. The authors focused on immunoregulatory components of colostrum (antidietary antibodies and TGF-β2) in the neonatal gut. This is a descriptive cross-sectional study of a convenience sample of 67 donated colostrum samples at different days after delivery, both raw and pasteurized. Antibody profiles were analyzed at different times during breastfeeding, and total and specific antibodies (IgM, IgA, and IgG subclasses) were compared with tetanus toxoid and ovalbumin using enzyme-linked immunosorbent assay. The processing effect on total and specific antibodies, as well as TGF-β2, was evaluated by paired analyses. No variations in immunological compounds were observed throughout the colostrum stage. The TGF-β2, antibodies' concentrations, and antibodies' specific reactivity after pasteurization did not vary significantly as days of lactation varied. Changes in antibody levels were dependent on isotype and IgG subclass, and IgG4 showed remarkable resistance to heating. Moreover, the effect of the pasteurization on specific reactivity was antigen dependent. The supply of relevant immunological components is stable throughout the colostrum stage. The effects of pasteurization on antibodies depend on isotype, subclass, and specificity. This information is relevant to improving the immunological quality of colostrum, especially for preterm newborns.

Anti-human immunodeficiency virus-1 antibody titers in injection drug users compared to sexually infected individuals

Directory of Open Access Journals (Sweden)

Bongertz Vera

2003-01-01

Full Text Available Sera from infected injection drug users (IDU have shown to have antibodies against synthetic human immunodeficiency virus-1 (HIV-1 envelope peptides more frequently. In this study, reactivity of 48 IDU plasma were compared to 60 plasmas obtained from sexually infected individuals (S. The overall reactivity of plasma from IDU compared to S was higher, and the reactivity titers were much higher for IDU plasma than S. IDU plasma also showed a broader antibody response. The higher reactivity titers were observed mainly for the gp41 immunodominant epitope and V3 peptides corresponding to the consensus sequences of HIV-1 subtypes/variants prevalent in Brazil (B, F, C indicating the specificity in the higher immune response of IDU.

Interference of daratumumab with pretransfusion testing, mimicking a high-titer, low avidity like antibody

Directory of Open Access Journals (Sweden)

Mei-Hwa Lin

2017-01-01

Full Text Available Daratumumab is a monoclonal immunoglobulin against CD38 and has been approved for treating patients with refractory multiple myeloma. The presence of daratumumab in the sera can interfere with pretransfusion testing due to the weakly expression of CD38 on red cells. The reactivity could be mistaken as autoantibody (if autocontrol is positive or alloantibody (if autocontrol is negative. We present a case that demonstrates daratumumab could mimic a high titer low avidity (HTLA alloantibody. A 34-year-old male patient of refractory myeloma was recruited in phase three clinical trial involving daratumumab. Samples were sent to the blood bank for pretransfusion testing. Without knowledge of patient having used daratumumab, we mistook the reactivity in the patient's sera as an HTLA antibody due to the results of negative autocontrol and high titers of antibody activity. Antibody screen showed a panreactive pattern and the reactivity against screening cells was up to a titer of 1: 1240. The reactivity was weaker against cord cells than adult cells, became weaker against ZZAP-treated cells and became negative against DDT-treated cells. A discussion with attending physician finally revealed the reactivity was due to the interference caused by daratumumab. The case demonstrates good communication is essential in performing pretransfusion testing for patients receiving daratumumab and other new biological regimens that can interfere with compatibility test.

Therapeutic preparations of IVIg contain naturally occurring anti-HLA-E antibodies that react with HLA-Ia (HLA-A/-B/-Cw) alleles.

Science.gov (United States)

Ravindranath, Mepur H; Terasaki, Paul I; Pham, Tho; Jucaud, Vadim; Kawakita, Satoru

2013-03-14

The US Food and Drug Administration approved intravenous immunoglobulin (IVIg), extracted from the plasma of thousands of blood donors, for removing HLA antibodies (Abs) in highly sensitized patients awaiting organ transplants. Since the blood of healthy individuals has HLA Abs, we tested different IVIg preparations for reactivity to HLA single antigen Luminex beads. All preparations showed high levels of HLA-Ia and -Ib reactivity. Since normal nonalloimmunized males have natural antibodies to the heavy chains (HCs) of HLA antigens, the preparations were then tested against iBeads coated only with intact HLA antigens. All IVIg preparations varied in level of antibody reactivity to intact HLA antigens. We raised monoclonal Abs against HLA-E that mimicked IVIg's HLA-Ia and HLA-Ib reactivity but reacted only to HLA-I HCs. Inhibition experiments with synthetic peptides showed that HLA-E shares epitopes with HLA-Ia alleles. Importantly, depleting anti-HLA-E Abs from IVIg totally eliminated the HLA-Ia reactivity of IVIg. Since anti-HLA-E mAbs react with HLA-Ia, they might be useful in suppressing HLA antibody production, similar to the way anti-RhD Abs suppress production. At the same time, anti-HLA-E mAb, which reacts only to HLA-I HCs, is unlikely to produce transfusion-related acute lung injury, in contrast to antibodies reacting to intact-HLA.

[Hyper-reactive malarial splenomegaly].

Science.gov (United States)

Maazoun, F; Deschamps, O; Barros-Kogel, E; Ngwem, E; Fauchet, N; Buffet, P; Froissart, A

2015-11-01

Hyper-reactive malarial splenomegaly is a rare and severe form of chronic malaria. This condition is a common cause of splenomegaly in endemic areas. The pathophysiology of hyper-reactive malarial splenomegaly involves an intense immune reaction (predominantly B cell-driven) to repeated/chronic infections with Plasmodium sp. The diagnosis may be difficult, due to a poorly specific clinical presentation (splenomegaly, fatigue, cytopenias), a long delay between residence in a malaria-endemic area and onset of symptoms, and a frequent absence of parasites on conventional thin and thick blood smears. A strongly contributive laboratory parameter is the presence of high levels of total immunoglobulin M. When the diagnostic of hyper-reactive malarial splenomegaly is considered, search for anti-Plasmodium antibodies and Plasmodium nucleic acids (genus and species) by PCR is useful. Diagnosis of hyper-reactive malarial splenomegaly relies on the simultaneous presence of epidemiological, clinical, biological and follow-up findings. Regression of both splenomegaly and hypersplenism following antimalarial therapy allows the differential diagnosis with splenic lymphoma, a common complication of hyper-reactive malarial splenomegaly. Although rare in Western countries, hyper-reactive malarial splenomegaly deserves increased medical awareness to reduce the incidence of incorrect diagnosis, to prevent progression to splenic lymphoma and to avoid splenectomy. Copyright © 2015 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

[VGKC-complex antibodies].

Science.gov (United States)

Watanabe, Osamu

2013-04-01

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

Carbohydrate Mimetic Peptides Augment Carbohydrate-Reactive Immune Responses in the Absence of Immune Pathology

International Nuclear Information System (INIS)

Hennings, Leah; Artaud, Cecile; Jousheghany, Fariba; Monzavi-Karbassi, Behjatolah; Pashov, Anastas; Kieber-Emmons, Thomas

2011-01-01

Among the most challenging of clinical targets for cancer immunotherapy are Tumor Associated Carbohydrate Antigens (TACAs). To augment immune responses to TACA we are developing carbohydrate mimetic peptides (CMPs) that are sufficiently potent to activate broad-spectrum anti-tumor reactivity. However, the activation of immune responses against terminal mono- and disaccharide constituents of TACA raises concerns regarding the balance between “tumor destruction” and “tissue damage”, as mono- and disaccharides are also expressed on normal tissue. To support the development of CMPs for clinical trial testing, we demonstrate in preclinical safety assessment studies in mice that vaccination with CMPs can enhance responses to TACAs without mediating tissue damage to normal cells expressing TACA. BALB/c mice were immunized with CMPs that mimic TACAs reactive with Griffonia simplicifolia lectin 1 (GS-I), and tissue reactivity of serum antibodies were compared with the tissue staining profile of GS-I. Tissues from CMP immunized mice were analyzed using hematoxylin and eosin stain, and Luxol-fast blue staining for myelination. Western blots of membranes from murine mammary 4T1 cells, syngeneic with BALB/c mice, were also compared using GS-I, immunized serum antibodies, and naive serum antibodies. CMP immunization enhanced glycan reactivities with no evidence of pathological autoimmunity in any immunized mice demonstrating that tissue damage is not an inevitable consequence of TACA reactive responses

Carbohydrate Mimetic Peptides Augment Carbohydrate-Reactive Immune Responses in the Absence of Immune Pathology

Energy Technology Data Exchange (ETDEWEB)

Hennings, Leah; Artaud, Cecile; Jousheghany, Fariba; Monzavi-Karbassi, Behjatolah; Pashov, Anastas; Kieber-Emmons, Thomas, E-mail: tke@uams.edu [Winthrop P. Rockefeller Cancer Institute and Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, AR 72205 (United States)

2011-11-11

Among the most challenging of clinical targets for cancer immunotherapy are Tumor Associated Carbohydrate Antigens (TACAs). To augment immune responses to TACA we are developing carbohydrate mimetic peptides (CMPs) that are sufficiently potent to activate broad-spectrum anti-tumor reactivity. However, the activation of immune responses against terminal mono- and disaccharide constituents of TACA raises concerns regarding the balance between “tumor destruction” and “tissue damage”, as mono- and disaccharides are also expressed on normal tissue. To support the development of CMPs for clinical trial testing, we demonstrate in preclinical safety assessment studies in mice that vaccination with CMPs can enhance responses to TACAs without mediating tissue damage to normal cells expressing TACA. BALB/c mice were immunized with CMPs that mimic TACAs reactive with Griffonia simplicifolia lectin 1 (GS-I), and tissue reactivity of serum antibodies were compared with the tissue staining profile of GS-I. Tissues from CMP immunized mice were analyzed using hematoxylin and eosin stain, and Luxol-fast blue staining for myelination. Western blots of membranes from murine mammary 4T1 cells, syngeneic with BALB/c mice, were also compared using GS-I, immunized serum antibodies, and naive serum antibodies. CMP immunization enhanced glycan reactivities with no evidence of pathological autoimmunity in any immunized mice demonstrating that tissue damage is not an inevitable consequence of TACA reactive responses.

Antibodies against homologous microbial caseinolytic proteases P characterise primary biliary cirrhosis.

Science.gov (United States)

Bogdanos, Dimitrios-Petrou; Baum, Harold; Sharma, Umesh C; Grasso, Alessandro; Ma, Yun; Burroughs, Andrew K; Vergani, Diego

2002-01-01

Antibodies to caseinolytic protease P(177-194) (ClpP(177-194)) of the proteolytic subunit of the Clp complex of Escherichia coli (E. coli) are uniquely present in primary biliary cirrhosis (PBC). Molecular mimicry between the regulatory subunit ClpX and the principal T-cell epitope of pyruvate dehydrogenase complex (PDC-E2) in PBC, has been proposed to account for this. Since ClpP is highly conserved among bacteria we investigated whether the micro-organisms triggering these antibodies may be other than E. coli. E. coli ClpP(177-194) is homologous with ClpP peptides of Yersinia enterocolitica (YEREN) and Haemophilus influenzae (HAEIN). Enzyme linked immunosorbent assay (ELISA) reactivity to these peptides was tested in 45 patients with PBC, 44 pathological and 32 healthy controls. Reactivity to at least one of the ClpP peptides was observed in 21 (47%) PBC patients, 5.8% pathological and 3.1% healthy controls (PECOLI ClpP(177-194), alone or in association with YEREN and/or HAEIN peptides, compared to three (14.2%) reactive with YEREN, two (9.5%) with YEREN/HAEIN and one (4.7%) with HAEIN peptide. Simultaneous reactivity to homologous sequences was due to cross-reactivity as confirmed by competition ELISAs. The PBC-specificity of anti-microbial ClpP reactivity is confirmed: the questions as to primary trigger(s) and relevance to PBC pathogenesis remain open.

The humoral immune response to Chlamydia trachomatis in patients with acute reactive arthritis

DEFF Research Database (Denmark)

Larsen, B; Birkelund, Svend; Mordhorst, CH

1994-01-01

. trachomatis cysteine rich outer membrane protein 2 (Omp2) and lipopolysaccharide (LPS) were detected in 10 patients. Thus 40% of the patients presented antibodies specific for C. trachomatis. There was no correlation between acute reactive arthritis and antibodies to heat-shock proteins GroEL, GroES and DnaK....

Lack of serologic evidence to link IgA nephropathy with celiac disease or immune reactivity to gluten.

Directory of Open Access Journals (Sweden)

Sina Moeller

Full Text Available IgA nephropathy is the most common form of primary glomerulonephritis worldwide. Mucosal infections and food antigens, including wheat gluten, have been proposed as potential contributing environmental factors. Increased immune reactivity to gluten and/or association with celiac disease, an autoimmune disorder triggered by ingestion of gluten, have been reported in IgA nephropathy. However, studies are inconsistent about this association. We aimed to evaluate the proposed link between IgA nephropathy and celiac disease or immune reactivity to gluten by conducting a comprehensive analysis of associated serologic markers in cohorts of well-characterized patients and controls. Study participants included patients with biopsy-proven IgA nephropathy (n = 99, unaffected controls of similar age, gender, and race (n = 96, and patients with biopsy-proven celiac disease (n = 30. All serum specimens were tested for IgG and IgA antibodies to native gliadin and deamidated gliadin, as well as IgA antibody to transglutaminase 2 (TG2. Anti-TG2 antibody-positive nephropathy patients and unaffected controls were subsequently tested for IgA anti-endomysial antibody and genotyped for celiac disease-associated HLA-DQ2 and -DQ8 alleles. In comparison to unaffected controls, there was not a statistically significant increase in IgA or IgG antibody reactivity to gliadin in individuals with IgA nephropathy. In addition, the levels of celiac disease-specific serologic markers, i.e., antibodies to deamidated gliadin and TG2, did not differ between IgA nephropathy patients and unaffected controls. Results of the additional anti-endomysial antibody testing and HLA genotyping were corroborative. The data from this case-control study do not reveal any evidence to suggest a significant role for celiac disease or immune reactivity to gluten in IgA nephropathy.

Lack of serologic evidence to link IgA nephropathy with celiac disease or immune reactivity to gluten.

Science.gov (United States)

Moeller, Sina; Canetta, Pietro A; Taylor, Annette K; Arguelles-Grande, Carolina; Snyder, Holly; Green, Peter H; Kiryluk, Krzysztof; Alaedini, Armin

2014-01-01

IgA nephropathy is the most common form of primary glomerulonephritis worldwide. Mucosal infections and food antigens, including wheat gluten, have been proposed as potential contributing environmental factors. Increased immune reactivity to gluten and/or association with celiac disease, an autoimmune disorder triggered by ingestion of gluten, have been reported in IgA nephropathy. However, studies are inconsistent about this association. We aimed to evaluate the proposed link between IgA nephropathy and celiac disease or immune reactivity to gluten by conducting a comprehensive analysis of associated serologic markers in cohorts of well-characterized patients and controls. Study participants included patients with biopsy-proven IgA nephropathy (n = 99), unaffected controls of similar age, gender, and race (n = 96), and patients with biopsy-proven celiac disease (n = 30). All serum specimens were tested for IgG and IgA antibodies to native gliadin and deamidated gliadin, as well as IgA antibody to transglutaminase 2 (TG2). Anti-TG2 antibody-positive nephropathy patients and unaffected controls were subsequently tested for IgA anti-endomysial antibody and genotyped for celiac disease-associated HLA-DQ2 and -DQ8 alleles. In comparison to unaffected controls, there was not a statistically significant increase in IgA or IgG antibody reactivity to gliadin in individuals with IgA nephropathy. In addition, the levels of celiac disease-specific serologic markers, i.e., antibodies to deamidated gliadin and TG2, did not differ between IgA nephropathy patients and unaffected controls. Results of the additional anti-endomysial antibody testing and HLA genotyping were corroborative. The data from this case-control study do not reveal any evidence to suggest a significant role for celiac disease or immune reactivity to gluten in IgA nephropathy.

Phage Display-Derived Cross-Reactive Neutralizing Antibody against Enterovirus 71 and Coxsackievirus A16.

Science.gov (United States)

Zhang, Xiao; Sun, Chunyun; Xiao, Xiangqian; Pang, Lin; Shen, Sisi; Zhang, Jie; Cen, Shan; Yang, Burton B; Huang, Yuming; Sheng, Wang; Zeng, Yi

2016-01-01

Enterovirus 71 (EV71) and coxsackievirus A16 (CVA16) are members of the Picornaviridae family and are considered the main causative agents of hand, foot and mouth disease (HFMD). In recent decades large HFMD outbreaks caused by EV71 and CVA16 have become significant public health concerns in the Asia-Pacific region. Vaccines and antiviral drugs are unavailable to prevent EV71 and CVA16 infection. In the current study, a chimeric antibody targeting a highly conserved peptide in the EV71 VP4 protein was isolated by using a phage display technique. The antibody showed cross-neutralizing capability against EV71 and CVA16 in vitro. The results suggest that this phage display-derived antibody will have great potential as a broad neutralizing antibody against EV71 and CVA16 after affinity maturation and humanization.

Identification of a novel dendritic cell surface antigen defined by carbohydrate specific CD24 antibody cross-reactivity.

Science.gov (United States)

Williams, L A; McLellan, A D; Summers, K L; Sorg, R V; Fearnley, D B; Hart, D N

1996-01-01

Dendritic cells (DC) are characterized as leucocytes that lack mature lineage specific markers and stimulate naive T-lymphocyte proliferation in vitro and in vivo. The mouse heat stable antigen (HSA) participates in T lymphocyte co-stimulation and is expressed by DC isolated from thymus, skin and spleen. The human HSA homologue, CD24, is predominantly expressed by B lymphocytes and granulocytes, but its expression on DC has not been studied in detail. CD24 clearly participates in B-lymphocyte signalling but co-stimulatory activity for T lymphocytes has not yet been described. We have examined the expression of CD24 on human peripheral blood DC populations isolated directly or following in vitro culture. The CD24 antigen was absent from blood DC however, cross-reactive sialylated carbohydrate epitopes were detected on DC with some CD24 monoclonal antibodies (mAb). These CD24 mAb define a protein surface antigen, which is expressed by an immature or resting subpopulation of peripheral blood DC and is down-regulated following activation differentiation in vitro. PMID:8911149

γ-Synuclein antibodies have neuroprotective potential on neuroretinal cells via proteins of the mitochondrial apoptosis pathway.

Directory of Open Access Journals (Sweden)

Corina Wilding

Full Text Available The family of synuclein proteins (α, β and γ are related to neurodegenerative disease e.g. Parkinson disease and Morbus Alzheimer. Additionally, a connection between γ-synuclein and glaucoma, a neurodegenerative disease characterized by a progressive loss of retinal ganglion cells, which finally leads to blindness, exists. The reason for the development of glaucoma is still unknown. Recent studies evaluating the participation of immunological components, demonstrate complex changed antibody reactivities in glaucoma patients in comparison to healthy people, showing not only up-regulations (e.g. alpha-fodrin antibody but also down-regulations (e.g. γ-synuclein antibody of antibodies in glaucoma patients. Up-regulated antibodies could be auto-aggressive, but the role of down-regulated antibodies is still unclear. Previous studies show a significant influence of the serum and the antibodies of glaucoma patients on protein expression profiles of neuroretinal cells. The aim of this study was to investigate the effect of γ-synuclein antibody on the viability and reactive oxygen species levels of a neuroretinal cell line (RGC-5 as well as their interaction with cellular proteins. We found a protective effect of γ-synuclein antibody resulting in an increased viability (up to 15% and decreased reactive oxygen species levels (up to -12% of glutamate and oxidative stressed RGC-5. These can be traced back to anti-apoptotic altered protein expressions in the mitochondrial apoptosis pathway indicated by mass spectrometry and validated by microarray analysis such as active caspase 3, bcl-2 associated-x-protein, S100A4, voltage-dependent anion channel, extracellular-signal-regulated-kinase (down-regulated and baculoviral IAP repeat-containing protein 6, phosphorylated extracellular-signal-regulated-kinase (up-regulated. These changed protein expression are triggered by the γ-synuclein antibody internalization of RGC-5 we could see in immunohistochemical

A malaria vaccine that elicits in humans antibodies able to kill Plasmodium falciparum.

Directory of Open Access Journals (Sweden)

Pierre Druilhe

2005-11-01

Full Text Available Plasmodium falciparum merozoite surface protein 3 is a malaria vaccine candidate that was identified, characterised, and developed based on a unique immuno-clinical approach. The vaccine construct was derived from regions fully conserved among various strains and containing B cell epitopes targeted by human antibodies (from malaria-immune adults that are able to mediate a monocyte-dependent parasite killing effect. The corresponding long synthetic peptide was administered to 36 volunteers, with either alum or Montanide ISA720 as adjuvant.Both formulations induced cellular and humoral immune responses. With alum, the responses lasted up to 12 mo. The vaccine-induced antibodies were predominantly of cytophilic classes, i.e., able to cooperate with effector cells. In vitro, the antibodies induced an inhibition of the P. falciparum erythrocytic growth in a monocyte-dependent manner, which was in most instances as high as or greater than that induced by natural antibodies from immune African adults. In vivo transfer of the volunteers' sera into P. falciparum-infected humanized SCID mice profoundly reduced or abrogated parasitaemia. These inhibitory effects were related to the antibody reactivity with the parasite native protein, which was seen in 60% of the volunteers, and remained in samples taken 12 mo postimmunisation.This is the first malaria vaccine clinical trial to clearly demonstrate antiparasitic activity by vaccine-induced antibodies by both in vitro and in vivo methods. The results, showing the induction of long-lasting antibodies directed to a fully conserved polypeptide, also challenge current concepts about malaria vaccines, such as unavoidable polymorphism, low antigenicity, and poor induction of immune memory.

Monkey-derived monoclonal antibodies against Plasmodium falciparum

International Nuclear Information System (INIS)

Stanley, H.A.; Reese, R.T.

1985-01-01

A system has been developed that allows efficient production of monkey monoclonal antibodies from owl monkeys. Splenocytes or peripheral blood lymphocytes from monkeys immune to the human malarial parasite, Plasmodium falciparum, were fused with P3X63 Ag8.653 mouse myelomas. The resulting hybridomas were screened by an indirect fluorescent antibody test for the production of monkey monoclonal antibodies (mAb) reactive with P. falciparum. Most of the mAb reacted with the P. falciparum merozoites and immunoprecipitated a parasite-derived glycoprotein having a relative molecular weight of 185,000. These mAb gave a minimum of five different immunoprecipitation patterns, thus demonstrating that a large number of polypeptides obtained when parasitized erythrocytes are solubilized share epitopes with this large glycoprotein. In addition, mAb were obtained that reacted with antigens associated with the infected erythrocyte membrane. One of these mAb bound a M/sub r/ 95,000 antigen. Radioimmunoprecipitation assays using 125 T-antibodies were done

Enzyme linked immunosorbent assay for detecting antibody to Trichomonas vaginalis: use of whole cells and aqueous extract as antigen.

Science.gov (United States)

Alderete, J F

1984-06-01

An enzyme linked immunosorbent assay (ELISA) for detecting antibody to antigenic Trichomonas vaginalis macromolecules has been identified using whole cells or an aqueous protein extract as antigen. The test was developed under optimum conditions using serum samples from experimental animals. The sensitivity of the ELISA was equal to or greater than that obtained by radioimmunoprecipitation and electrophoresis-fluorography techniques. The ELISA was capable of assessing antibody responses during the development of lesions in animals inoculated subcutaneously and it reproducibly measured the individual classes immunoglobulins directed at T vaginalis. The colorimetric assay was also suitable for showing cross reactivity between trichomonal species as well as between different strains of T vaginalis. Conditions established for monitoring antibody to trichomanads in immunised rabbits or infected mice were equally effective for human materials, such as serum or vaginal washes. Serum from experimental animals or infected people showed high concentrations of IgG, IgA, and IgM antibody to trichomonads. Only antibodies of the IgG and IgA class were detected in vaginal washes from women with acute trichomoniasis. No IgE antibody to trichomonads was found under a variety of conditions in serum samples from patients or experimental animals.

A Distinct Class of Antibodies May Be an Indicator of Gray Matter Autoimmunity in Early and Established Relapsing Remitting Multiple Sclerosis Patients

Directory of Open Access Journals (Sweden)

Ann J. Ligocki

2015-10-01

Full Text Available * These authors contributed equally to the work in this manuscript.We have previously identified a distinct class of antibodies expressed by B cells in the cerebrospinal fluid (CSF of early and established relapsing remitting multiple sclerosis (RRMS patients that is not observed in healthy donors. These antibodies contain a unique pattern of mutations in six codons along VH4 antibody genes that we termed the antibody gene signature (AGS. In fact, patients who have such B cells in their CSF are identified as either having RRMS or developing RRMS in the future. As mutations in antibody genes increase antibody affinity for particular antigens, the goal for this study was to investigate whether AGS+ antibodies bind to brain tissue antigens. Single B cells were isolated from the CSF of 10 patients with early or established RRMS. We chose 32 of these B cells that expressed antibodies enriched for the AGS for further study. We generated monoclonal full-length recombinant human antibodies (rhAbs and used both immunological assays and immunohistochemistry to investigate the capacity of these AGS+ rhAbs to bind brain tissue antigens. AGS+ rhAbs did not recognize myelin tracts in the corpus callosum. Instead, AGS+ rhAbs recognized neuronal nuclei and/or astrocytes, which are prevalent in the cortical gray matter. This pattern was unique to the AGS+ antibodies from early and established RRMS patients, as AGS+ antibodies from an early neuromyelitis optica patient did not display the same reactivity. Prevalence of CSF-derived B cells expressing AGS+ antibodies that bind to these cell types may be an indicator of gray matter-directed autoimmunity in early and established RRMS patients.

Evaluation of three commercial rapid tests for detecting antibodies to human immunodeficiency virus.

Science.gov (United States)

Ng, K P; Saw, T L; Baki, A; Kamarudin, R

2003-08-01

Determine HIV-1/2, Chembio HIV-1/2 STAT-PAK and PenTest are simple/rapid tests for the detection of antibodies to HIV-1 and HIV-2 in human whole blood, serum and plasma samples. The assay is one step and the result is read visually within 15 minutes. Using 92 known HIV-1 reactive sera and 108 known HIV-1 negative sera, the 3 HIV tests correctly identified all the known HIV-1 reactive and negative samples. The results indicated that Determine HIV-1/2, Chembio HIV-1/2 STAT-PAK and PenTest HIV are as sensitive and specific (100% concordance) as Microparticle Enzyme Immunoassay. The data indicated that these 3 HIV tests are effective testing systems for diagnosis of HIV infection in a situation when the conventional Enzyme Immunoassay is not suitable.

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

DEFF Research Database (Denmark)

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

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

Detection systems for antibody responses against herpes B virus

OpenAIRE

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

2017-01-01

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

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

Science.gov (United States)

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

2014-10-01

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

An ELISA to Detect Serum Antibodies to the Salivary Gland Toxin of Ixodes holocyclus Neumann in Dogs and Rodents

Directory of Open Access Journals (Sweden)

S. Hall-Mendelin

2011-01-01

Full Text Available The Ixodes holocyclus tick causes paralysis in up to 10,000 companion and domestic animals each year in Australia. Treatment requires the removal of the parasite and the administration of a commercial tick antiserum that is prepared from hyperimmune dogs. Each batch of this serum is initially tested for toxin-neutralising potency in a mouse bioassay that is expensive, time consuming, and subjective. With the aim of developing a rapid in vitro assay to replace the bioassay, we used a partially purified antigen prepared from I. holocyclus salivary glands to develop an ELISA to detect toxin-reactive antibodies in hyperimmune dog sera. The optimised ELISA reliably detected antibodies reactive to I. holocyclus salivary gland antigens. Parallel testing of sera with a negative control antigen prepared from the salivary glands of the nontoxic tick Rhipicephalus (Boophilus microplus provided further evidence that we were detecting toxin-specific antibodies in the assay. Using the ELISA, we could also detect antibodies induced in rats after experimental infestation with I. holocyclus. This assay shows promise as an alternative means of assessing the potency of batches of hyperimmune dog serum and to screen for toxin-reactive monoclonal antibodies produced from immunised rodents.

Dengue virus specific IgY provides protection following lethal dengue virus challenge and is neutralizing in the absence of inducing antibody dependent enhancement.

Science.gov (United States)

Fink, Ashley L; Williams, Katherine L; Harris, Eva; Alvine, Travis D; Henderson, Thomas; Schiltz, James; Nilles, Matthew L; Bradley, David S

2017-07-01

Dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) are severe disease manifestations that can occur following sequential infection with different dengue virus serotypes (DENV1-4). At present, there are no licensed therapies to treat DENV-induced disease. DHF and DSS are thought to be mediated by serotype cross-reactive antibodies that facilitate antibody-dependent enhancement (ADE) by binding to viral antigens and then Fcγ receptors (FcγR) on target myeloid cells. Using genetically engineered DENV-specific antibodies, it has been shown that the interaction between the Fc portion of serotype cross-reactive antibodies and FcγR is required to induce ADE. Additionally, it was demonstrated that these antibodies were as neutralizing as their non-modified variants, were incapable of inducing ADE, and were therapeutic following a lethal, antibody-enhanced infection. Therefore, we hypothesized that avian IgY, which do not interact with mammalian FcγR, would provide a novel therapy for DENV-induced disease. We demonstrate here that goose-derived anti-DENV2 IgY neutralized DENV2 and did not induce ADE in vitro. Anti-DENV2 IgY was also protective in vivo when administered 24 hours following a lethal DENV2 infection. We were also able to demonstrate via epitope mapping that both full-length and alternatively spliced anti-DENV2 IgY recognized different epitopes, including epitopes that have not been previously identified. These observations provide evidence for the potential therapeutic applications of goose-derived anti-DENV2 IgY.

Dengue virus specific IgY provides protection following lethal dengue virus challenge and is neutralizing in the absence of inducing antibody dependent enhancement.

Directory of Open Access Journals (Sweden)

Ashley L Fink

2017-07-01

Full Text Available Dengue hemorrhagic fever (DHF and dengue shock syndrome (DSS are severe disease manifestations that can occur following sequential infection with different dengue virus serotypes (DENV1-4. At present, there are no licensed therapies to treat DENV-induced disease. DHF and DSS are thought to be mediated by serotype cross-reactive antibodies that facilitate antibody-dependent enhancement (ADE by binding to viral antigens and then Fcγ receptors (FcγR on target myeloid cells. Using genetically engineered DENV-specific antibodies, it has been shown that the interaction between the Fc portion of serotype cross-reactive antibodies and FcγR is required to induce ADE. Additionally, it was demonstrated that these antibodies were as neutralizing as their non-modified variants, were incapable of inducing ADE, and were therapeutic following a lethal, antibody-enhanced infection. Therefore, we hypothesized that avian IgY, which do not interact with mammalian FcγR, would provide a novel therapy for DENV-induced disease. We demonstrate here that goose-derived anti-DENV2 IgY neutralized DENV2 and did not induce ADE in vitro. Anti-DENV2 IgY was also protective in vivo when administered 24 hours following a lethal DENV2 infection. We were also able to demonstrate via epitope mapping that both full-length and alternatively spliced anti-DENV2 IgY recognized different epitopes, including epitopes that have not been previously identified. These observations provide evidence for the potential therapeutic applications of goose-derived anti-DENV2 IgY.

Monoclonal antibodies to human chorionic gonadotropin and their application to two-site sandwich radioimmunoassay

International Nuclear Information System (INIS)

Mizuchi, A.; Iio, M.; Miyachi, Y.

1984-01-01

Monoclonal antibodies were prepared against human chorionic gonadotropin (HCG). One monoclonal antibody recognized a conformational determinant expressed only on native HCG molecule and another monoclonal antibody had the specificity for the epitopes located on the β-subunit of HCG. Monoclonal antibodies reacting with different antigenic determinants on the HCG molecule were used to develop a simplified 2-site sandwich radioimmunoassay in which one monoclonal antibody was immobilized and another labeled with 125 iodine. This assay was highly specific for HCG and there was no cross-reactivity with α,β-subunit of HCG, luteinizing hormone and follicle stimulating hormone. (Auth.)

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

International Nuclear Information System (INIS)

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

1991-01-01

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

T-cell activation. VI. Inhibitory and stimulatory effects of anti-major histocompatibility complex class I antibodies in allogeneic mixed lymphocyte culture

DEFF Research Database (Denmark)

Röpke, M; Röpke, C; Claesson, Mogens Helweg

1993-01-01

Murine T splenocytes stimulated in primary allogeneic mixed lymphocyte culture (MLC) were incubated with soluble anti-major histocompatibility complex (MHC) class I monoclonal antibodies. These antibodies induced inhibition in the cytotoxicity of the responding population and this inhibition...... was not dependent on the domain on class I molecules recognized by the antibodies. Cross-reactivity of the antibodies between the responder and stimulating cell population caused a marked reduction in the inhibitory effect compared to systems where no such cross-reactivity was present. Saturating levels...... of the antibodies caused a reduction in generation of T-cell cytotoxicity, whereas low concentrations stimulated the same response. These results demonstrate that the MHC class I molecules of T cells are of significant importance in antigen-induced signal transduction....

Should we ignore western blots when selecting antibodies for other applications?

DEFF Research Database (Denmark)

Uhlén, Mathias

2017-01-01

.In the Human Protein Atlas (HPA) program, we have validated more than 24,000 in-house-generated antibodies directed to 17,000 human target proteins2. Although there is often a correlation between performance in different applications, we have observed many examples of antibodies that show strong support...... applications and that this influences the epitopes exposed on the target protein, which might have profound consequences for the ability of a given antibody to bind specifically to its target. As an example, proteins that are analyzed by immunohistochemistry (IHC) are normally first cross-linked with formalin.......In conclusion, western blot and protein array analyses can indeed be useful tools when selecting specific antibodies for other applications. The use of these methods is encouraged both for antibody providers and users, and antibodies with signs of cross-reactivity in these applications should be treated...

[Construction of human phage antibody library and screening for human monoclonal antibodies of amylin].

Science.gov (United States)

Gong, Qian; Li, Chang-ying; Chang, Ji-wu; Zhu, Tie-hong

2012-06-01

To screen monoclonal antibodies to amylin from a constructed human phage antibody library and identify their antigenic specificity and combining activities. The heavy chain Fd fragment and light chain of human immunoglobulin genes were amplified from peripheral blood lymphocytes of healthy donors using RT-PCR, and then inserted into phagemid pComb3XSS to generate a human phage antibody library. The insertion of light chain or heavy chain Fd genes were identified by PCR after the digestion of Sac I, Xba I, Xho Iand Spe I. One of positive clones was analyzed by DNA sequencing. The specific anti-amylin clones were screened from antibody library against human amylin antigens and then the positive clones were determined by Phage-ELISA analysis. A Fab phage antibody library with 0.8×10(8); members was constructed with the efficacy of about 70%. DNA sequence analysis indicated V(H); gene belonged to V(H);3 gene family and V(λ); gene belonged to the V(λ); gene family. Using human amylin as panning antigen, specific anti-amylin Fab antibodies were enriched by screening the library for three times. Phage-ELISA assay showed the positive clones had very good specificity to amylin antigen. The successful construction of a phage antibody library and the identification of anti-amylin Fab antibodies provide a basis for further study and preparation of human anti-amylin antibodies.

High-efficiency astatination of antibodies using N-iodosuccinimide as the oxidising agent in labelling of N-succinimidyl 3-(trimethylstannyl)benzoate

International Nuclear Information System (INIS)

Lindegren, S.; Andersson, H.; Baeck, T.; Jacobsson, L.; Karlsson, B.; Skarnemark, G.

2001-01-01

Monoclonal antibodies C215, reactive with colorectal carcinomas, and MOv18, reactive with most of the ovarian carcinomas, were radiohalogenated with [ 211 At]astatine. The radiohalogen was conjugate coupled to antibodies via the intermediate labelling reagent N-succinimidyl-3-(trimethylstannyl)benzoate (m-MeATE) in a two-step, single-pot reaction. Optimisation of the labelling of the reagent was achieved using N-iodosuccinimide, NIS, as the oxidising agent. The yields ranged from 69-95% in the labelling of 0.1-1.0 nmole of the m-MeATE precursor. Subsequent conjugation to antibodies resulted in yields of 58±7%. In vitro binding to tumour cells showed that the immunoreactivity of both antibodies was retained after astatine labelling

Significance of isolated reactive treponemal chemiluminescence immunoassay results.

Science.gov (United States)

Hunter, Michael G; Robertson, Peter W; Post, Jeffrey J

2013-05-01

Isolated reactive serum treponemal chemiluminescence immunoassay (CIA) specimens cause clinical uncertainty. Sera were screened by CIA, and reactive samples underwent reflex testing with rapid plasma reagin (RPR), Treponema pallidum particle agglutination (TPPA), and fluorescent treponemal antibody absorption (FTA Abs) assays. Samples reactive only on the CIA were deemed "isolated" reactive CIA samples. We undertook detailed review of a subset of subjects with isolated reactive CIA specimens. Of 28 261 specimens, 1171 (4.1%) were reactive on CIA, of which 133 (11.3%) had isolated CIA reactivity. Most subjects (66 of 82 [80.5%]) with isolated reactive CIA specimens were from high-prevalence populations. We found evidence of CIA, TPPA, and FTA Abs seroreversion. The median chemiluminescent signal-to-cutoff ratio was similar for isolated reactive CIA sera and sera that were reactive on either FTA Abs or TPPA assays (2.19 vs 2.32; P = .15) but lower than for sera reactive on both FTA Abs and TPPA assays (12.37; P < .001) or for sera reactive on RPR assays (25.53; P < .001). A total of 11 of 20 patients (55%) with an isolated reactive CIA specimen who underwent medical record review had previous or subsequent evidence of syphilis infection. Isolated reactive CIA specimens may represent true T. pallidum infection and may be found after seroreversion of traditional treponemal assays.

Production and characterization of polyclonal antibody against a synthetic peptide from β-actin protein

Directory of Open Access Journals (Sweden)

Nazila Amini

2014-06-01

Full Text Available Objective(s:Antibodies against actin, as one of the most widely studied structural and multifunctional housekeeping proteins in eukaryotic cells, are used as internal loading controls in western blot analyses. The aim of this study was to produce polyclonal antibody against a synthetic peptide derived from N-terminal region of β-actin protein to be used as a protein loading control in western blot and other assay systems. Materials and Methods: A synthetic peptide derived from β-actin protein was designed and conjugated to Keyhole limpet hemocyanin (KLH (and used to immunize a white New Zealand rabbit. The antibody was purified from serum by affinity chromatography column. The purity of the antibody was determined by SDS-PAGE and its ability to recognize the immunizing peptide was measured by ELISA. The reactivity of the antibody with β-actin protein in a panel of different cell lysates was then evaluated by western blot. In addition, the reactivity of the antibody with the corresponding protein was also evaluated by Immunocytochemistry and Immunohistochemistry in different samples. Results: The antibody could recognize the immunizing peptide in ELISA. It could also recognize            β-actin protein in western blot as well as in immunocytochemistry and immunohistochemistry. Conclusion: Our data suggest that this antibody may be used as an internal control in western blot analyses as well as in other immunological applications such as ELISA,immunocytochemistry and immunohistochemistry.

The association of Varicella zoster virus reactivation with Bell's palsy in children.

Science.gov (United States)

Abdel-Aziz, Mosaad; Azab, Noha A; Khalifa, Badwy; Rashed, Mohammed; Naguib, Nader

2015-03-01

Bell's palsy is considered the most common cause of facial nerve paralysis in children. Although different theories have been postulated for its diagnosis, reactivation of the Varicella zoster virus (VZV) has been implicated as one of the causes of Bell's palsy. The aim of the study was to evaluate the association of Varicella-zoster virus infection with Bell's palsy and its outcome in children. A total of 30 children with Bell's palsy were recruited and were assayed for evidence of VZV infection. The severity of facial nerve dysfunction and the recovery rate were evaluated according to House-Brackmann Facial Nerve Grading Scale (HB FGS). Paired whole blood samples from all patients were obtained at their initial visit and 3 weeks later, and serum samples were analyzed for VZV IgG and IgM antibodies using ELISA. A significantly higher percentage of Bell's palsy patients were seropositive for VZV IgM antibodies than controls (36.6% of patients vs 10% of controls) while for VZV IgG antibodies the difference was statistically nonsignificant. HB FGS in Bell's palsy patients with serologic evidence of VZV recent infection or reactivation showed a statistiacally significant less cure rate than other patients. VZV reactivation may be an important cause of acute peripheral facial paralysis in children. The appropriate diagnosis of VZV reactivation should be done to improve the outcome and the cure rate by the early use of antiviral treatment. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

The molecular basis of the antigenic cross-reactivity between measles and cowpea mosaic viruses

International Nuclear Information System (INIS)

Olszewska, Wieslawa; Steward, Michael W.

2003-01-01

Two nonrelated viruses, cowpea mosaic virus (wtCPMV) and measles virus (MV), were found to induce cross-reactive antibodies. The nature of this cross-reactivity was studied and results are presented here demonstrating that antiserum raised against wtCPMV reacted with peptide from the fusion (F) protein of MV. Furthermore, the F protein of MV was shown to share an identical conformational B cell epitope with the small subunit of CPMV coat protein. Passive transfer of anti-wtCPMV antibodies into BALB/c mice conferred partial protection against measles virus induced encephalitis. The results are discussed in the context of cross-protection

Applying Unique Molecular Identifiers in Next Generation Sequencing Reveals a Constrained Viral Quasispecies Evolution under Cross-Reactive Antibody Pressure Targeting Long Alpha Helix of Hemagglutinin

Science.gov (United States)

Hauck, Nastasja C.; Kirpach, Josiane; Kiefer, Christina; Farinelle, Sophie; Morris, Stephen A.; Muller, Claude P.; Lu, I-Na

2018-01-01

To overcome yearly efforts and costs for the production of seasonal influenza vaccines, new approaches for the induction of broadly protective and long-lasting immune responses have been developed in the past decade. To warrant safety and efficacy of the emerging crossreactive vaccine candidates, it is critical to understand the evolution of influenza viruses in response to these new immune pressures. Here we applied unique molecular identifiers in next generation sequencing to analyze the evolution of influenza quasispecies under in vivo antibody pressure targeting the hemagglutinin (HA) long alpha helix (LAH). Our vaccine targeting LAH of hemagglutinin elicited significant seroconversion and protection against homologous and heterologous influenza virus strains in mice. The vaccine not only significantly reduced lung viral titers, but also induced a well-known bottleneck effect by decreasing virus diversity. In contrast to the classical bottleneck effect, here we showed a significant increase in the frequency of viruses with amino acid sequences identical to that of vaccine targeting LAH domain. No escape mutant emerged after vaccination. These results not only support the potential of a universal influenza vaccine targeting the conserved LAH domains, but also clearly demonstrate that the well-established bottleneck effect on viral quasispecies evolution does not necessarily generate escape mutants. PMID:29587397

Applying Unique Molecular Identifiers in Next Generation Sequencing Reveals a Constrained Viral Quasispecies Evolution under Cross-Reactive Antibody Pressure Targeting Long Alpha Helix of Hemagglutinin

Directory of Open Access Journals (Sweden)

Nastasja C. Hauck

2018-03-01

Full Text Available To overcome yearly efforts and costs for the production of seasonal influenza vaccines, new approaches for the induction of broadly protective and long-lasting immune responses have been developed in the past decade. To warrant safety and efficacy of the emerging crossreactive vaccine candidates, it is critical to understand the evolution of influenza viruses in response to these new immune pressures. Here we applied unique molecular identifiers in next generation sequencing to analyze the evolution of influenza quasispecies under in vivo antibody pressure targeting the hemagglutinin (HA long alpha helix (LAH. Our vaccine targeting LAH of hemagglutinin elicited significant seroconversion and protection against homologous and heterologous influenza virus strains in mice. The vaccine not only significantly reduced lung viral titers, but also induced a well-known bottleneck effect by decreasing virus diversity. In contrast to the classical bottleneck effect, here we showed a significant increase in the frequency of viruses with amino acid sequences identical to that of vaccine targeting LAH domain. No escape mutant emerged after vaccination. These results not only support the potential of a universal influenza vaccine targeting the conserved LAH domains, but also clearly demonstrate that the well-established bottleneck effect on viral quasispecies evolution does not necessarily generate escape mutants.

Cloning, monoclonal antibody production, and bodily distribution pattern of a bovine lipocalin.

Science.gov (United States)

Japaridze, Tamar; Senda, Akitsugu; Nozaki, Hirofumi; Yanagida, Mayumi; Suzuki, Takumi; Ganzorig, Khuukhenbaatar; Kushi, Yasunori; Kida, Katsuya; Urashima, Tadasu; Bruckmaier, Rupert M; Fukuda, Kenji

2012-01-01

A bovine lipocalin, previously identified as a putative odorant-binding protein in bovine colostrum (bcOBP), was cloned and expressed, and its monoclonal antibody was established. bcOBP was constantly secreted into milk on day of parturition until at least 10 d postpartum at a concentration of 181±39 µg/L. Besides milk, bcOBP occurred in the nasal mucus, saliva, amniotic fluid, vaginal discharge, and blood plasma. Despite its low concentration, the distribution pattern and the finding that bcOBP harbored a characteristic sequence motif, CxxxC, which is conserved among insect and mammal pheromone binding proteins, suggest that bcOBP functions as a pheromone carrier. The presence of bcOBP in the plasma at varied concentrations depending on the lactation period does not exclude the possibility that bcOBP is secreted into milk from the blood. Cross-reactivity of the monoclonal antibody indicated presence of proteins homologous to bcOBP in the colostrum of farm animals of Cetartiodactyla.

Generation and characterization of function-blocking anti-ectodysplasin A (EDA) monoclonal antibodies that induce ectodermal dysplasia.

Science.gov (United States)

Kowalczyk-Quintas, Christine; Willen, Laure; Dang, Anh Thu; Sarrasin, Heidi; Tardivel, Aubry; Hermes, Katharina; Schneider, Holm; Gaide, Olivier; Donzé, Olivier; Kirby, Neil; Headon, Denis J; Schneider, Pascal

2014-02-14

Development of ectodermal appendages, such as hair, teeth, sweat glands, sebaceous glands, and mammary glands, requires the action of the TNF family ligand ectodysplasin A (EDA). Mutations of the X-linked EDA gene cause reduction or absence of many ectodermal appendages and have been identified as a cause of ectodermal dysplasia in humans, mice, dogs, and cattle. We have generated blocking antibodies, raised in Eda-deficient mice, against the conserved, receptor-binding domain of EDA. These antibodies recognize epitopes overlapping the receptor-binding site and prevent EDA from binding and activating EDAR at close to stoichiometric ratios in in vitro binding and activity assays. The antibodies block EDA1 and EDA2 of both mammalian and avian origin and, in vivo, suppress the ability of recombinant Fc-EDA1 to rescue ectodermal dysplasia in Eda-deficient Tabby mice. Moreover, administration of EDA blocking antibodies to pregnant wild type mice induced in developing wild type fetuses a marked and permanent ectodermal dysplasia. These function-blocking anti-EDA antibodies with wide cross-species reactivity will enable study of the developmental and postdevelopmental roles of EDA in a variety of organisms and open the route to therapeutic intervention in conditions in which EDA may be implicated.

Generation and Characterization of Function-blocking Anti-ectodysplasin A (EDA) Monoclonal Antibodies That Induce Ectodermal Dysplasia*

Science.gov (United States)

Kowalczyk-Quintas, Christine; Willen, Laure; Dang, Anh Thu; Sarrasin, Heidi; Tardivel, Aubry; Hermes, Katharina; Schneider, Holm; Gaide, Olivier; Donzé, Olivier; Kirby, Neil; Headon, Denis J.; Schneider, Pascal

2014-01-01

Development of ectodermal appendages, such as hair, teeth, sweat glands, sebaceous glands, and mammary glands, requires the action of the TNF family ligand ectodysplasin A (EDA). Mutations of the X-linked EDA gene cause reduction or absence of many ectodermal appendages and have been identified as a cause of ectodermal dysplasia in humans, mice, dogs, and cattle. We have generated blocking antibodies, raised in Eda-deficient mice, against the conserved, receptor-binding domain of EDA. These antibodies recognize epitopes overlapping the receptor-binding site and prevent EDA from binding and activating EDAR at close to stoichiometric ratios in in vitro binding and activity assays. The antibodies block EDA1 and EDA2 of both mammalian and avian origin and, in vivo, suppress the ability of recombinant Fc-EDA1 to rescue ectodermal dysplasia in Eda-deficient Tabby mice. Moreover, administration of EDA blocking antibodies to pregnant wild type mice induced in developing wild type fetuses a marked and permanent ectodermal dysplasia. These function-blocking anti-EDA antibodies with wide cross-species reactivity will enable study of the developmental and postdevelopmental roles of EDA in a variety of organisms and open the route to therapeutic intervention in conditions in which EDA may be implicated. PMID:24391090

Identification of Eimeria acervulina conoid antigen using chicken monoclonal antibody.

Science.gov (United States)

Matsubayashi, Makoto; Minoura, Chisa; Kimura, Shintaro; Tani, Hiroyuki; Furuya, Masaru; Lillehoj, Hyun S; Matsuda, Haruo; Takenaka, Shigeo; Hatta, Takeshi; Tsuji, Naotoshi; Sasai, Kazumi

2016-11-01

In the poultry industry, Eimeria spp. is one of the important pathogens which cause significant economic losses. We have previously generated a chicken monoclonal antibody (mAb), 6D-12-G10, with specificity for an antigen located in the apical cytoskeleton of Eimeria acervulina and with cross-reactive among Apicomplexan parasites, including other Eimeria spp., Toxoplasma, Neospora, and Cryptosporidium spp. Furthermore, the protein of Cryptosporidium parvum recognized by the 6D-12-G10 has been identified as elongation factor-1α (EF-1α). In the present study, to identify the target molecule of E. acervulina by the mAb, we performed two-dimensional Western blotting analysis. Finally, we found two positive molecules which are identified as EF-1α and a related protein. Our previous finding using C. parvum and the results in this study suggest that EF-1α could be associated with the invasion facilitated by the cytoskeleton at the apical region of zoites.

Generation of a rabbit single-chain fragment variable (scFv) antibody for specific detection of Bradyrhizobium sp. DOA9 in both free-living and bacteroid forms.

Science.gov (United States)

Vu, Nguyen Xuan; Pruksametanan, Natcha; Srila, Witsanu; Yuttavanichakul, Watcharin; Teamtisong, Kamonluck; Teaumroong, Neung; Boonkerd, Nantakorn; Tittabutr, Panlada; Yamabhai, Montarop

2017-01-01

A simple and reliable method for the detection of specific nitrogen-fixing bacteria in both free-living and bacteroid forms is essential for the development and application of biofertilizer. Traditionally, a polyclonal antibody generated from an immunized rabbit was used for detection. However, the disadvantages of using a polyclonal antibody include limited supply and cross-reactivity to related bacterial strains. This is the first report on the application of phage display technology for the generation of a rabbit recombinant monoclonal antibody for specific detection and monitoring of nitrogen-fixing bacteria in both free-living form and in plant nodules. Bradyrhizobium sp. DOA9, a broad host range soil bacteria, originally isolated from the root nodules of Aeschynomene americana in Thailand was used as a model in this study. A recombinant single-chain fragment variable (scFv) antibody library was constructed from the spleen of a rabbit immunized with DOA9. After three rounds of biopanning, one specific phage-displayed scFv antibody, designated bDOA9rb8, was identified. Specific binding of this antibody was confirmed by phage enzyme-linked immunosorbent assay (phage ELISA). The phage antibody could bind specifically to DOA9 in both free-living cells (pure culture) and bacteroids inside plant nodules. In addition to phage ELISA, specific and robust immunofluorescence staining of both free-living and bacteroid forms could also be observed by confocal-immunofluorescence imaging, without cross-reactivity with other tested bradyrhizobial strains. Moreover, specific binding of free scFv to DOA9 was also demonstrated by ELISA. This recombinant antibody can also be used for the study of the molecular mechanism of plant-microbe interactions in the future.

The effects of wet cupping on serum high-sensitivity C-reactive protein and heat shock protein 27 antibody titers in patients with metabolic syndrome.

Science.gov (United States)

Farahmand, Seyed Kazem; Gang, Li Zhi; Saghebi, Seyed Ahmad; Mohammadi, Maryam; Mohammadi, Shabnam; Mohammadi, Ghazaleh; Ferns, Gordan A; Ghanbarzadeh, Majid; Razmgah, Gholamreza Ghayour; Ramazani, Zahra; Ghayour-Mobarhan, Majid; Esmaily, Habibollah; Bahrami Taghanaki, Hamidreza; Azizi, Hoda

2014-08-01

It has previously been reported that increased level of serum heat shock proteins (Hsps) antibody in patients with metabolic syndrome. It is possible that the expression of Hsp and inflammatory markers can be affected by cupping and traditional Chinese medicine. There is a little data investigating the effects of cupping on markers of inflammation and Hsp proteins, hence, the objective of this study was evaluation of the effects of wet cupping on serum high-sensitivity C-reactive protein (hs-CRP) and Hsp27 antibody titers in patients with metabolic syndrome. Serum Hs-CRP and Hsp27 antibody titers were assessed in samples from 126 patients with metabolic syndrome (18-65 years of age) at baseline, and after 6 and 12 weeks after treatment. One hundred and twenty-six patients were randomly divided into the experimental group treated with wet cupping combined with dietary advice, and the control group treated with dietary advice alone using a random number table. Eight patients in case group and five subjects in control groups were excluded from the study. Data were analyzed using SPSS 15.0 software and a repeated measure ANCOVA. Serum hs-CRP titers did not change significantly between groups (p>0.05) and times (p=0.27). The same result was found for Hsp27 titers (p>0.05). Wet-cupping on the interscapular region has no effect on serum hs-CRP and Hsp27 patients with metabolic syndrome. Copyright © 2014 Elsevier Ltd. All rights reserved.

Development of an EGFRvIII specific recombinant antibody

Directory of Open Access Journals (Sweden)

Li Gordon

2010-10-01

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

Antibody informatics for drug discovery

DEFF Research Database (Denmark)

Shirai, Hiroki; Prades, Catherine; Vita, Randi

2014-01-01

to the antibody science in every project in antibody drug discovery. Recent experimental technologies allow for the rapid generation of large-scale data on antibody sequences, affinity, potency, structures, and biological functions; this should accelerate drug discovery research. Therefore, a robust bioinformatic...... infrastructure for these large data sets has become necessary. In this article, we first identify and discuss the typical obstacles faced during the antibody drug discovery process. We then summarize the current status of three sub-fields of antibody informatics as follows: (i) recent progress in technologies...... for antibody rational design using computational approaches to affinity and stability improvement, as well as ab-initio and homology-based antibody modeling; (ii) resources for antibody sequences, structures, and immune epitopes and open drug discovery resources for development of antibody drugs; and (iii...

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

Directory of Open Access Journals (Sweden)

Komei Ito

2005-01-01

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

Human alpha-enolase from endothelial cells as a target antigen of anti-endothelial cell antibody in Behçet's disease.

Science.gov (United States)

Lee, Kwang Hoon; Chung, Hae-Shin; Kim, Hyoung Sup; Oh, Sang-Ho; Ha, Moon-Kyung; Baik, Ja-Hyun; Lee, Sungnack; Bang, Dongsik

2003-07-01

To identify and recombine a protein of the human dermal microvascular endothelial cell (HDMEC) that specifically reacts with anti-endothelial cell antibody (AECA) in the serum of patients with Behçet's disease (BD), and to evaluate the usefulness of this protein in BD. The proteomics technique, with 2-dimensional gel electrophoresis and matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry, was used to identify and recombine HDMEC antigen. Western blotting and enzyme-linked immunosorbent assay (ELISA) of recombinant protein isolated by gene cloning were performed on serum from healthy controls, patients with BD, and patients with other rheumatic diseases (rheumatoid arthritis, systemic lupus erythematosus, and Wegener's granulomatosis). Eighteen of 40 BD patients had serum IgM antibody to HDMEC antigen. The purified protein that reacted with AECA in BD patient sera was found to be alpha-enolase by 2-dimensional gel electrophoresis followed by immunoblotting and MALDI-TOF mass spectrometry. Recombinant alpha-enolase protein was isolated and refined by gene cloning. On Western blots, AECA-positive IgM from the sera of patients with active BD reacted strongly with recombinant human alpha-enolase. BD patient sera positive for anti-alpha-enolase did not react with human gamma-enolase. On dot-blotting, reactivity to human alpha-enolase was detected only in the IgM-positive group. Fifteen of the 18 AECA-positive sera that were positive for the HDMEC antigen showed reactivity to recombinant alpha-enolase IgM antibody by ELISA. The alpha-enolase protein is the target protein of serum AECA in BD patients. This is the first report of the presence of IgM antibodies to alpha-enolase in endothelial cells from the serum of BD patients. Although further studies relating this protein to the pathogenesis of BD will be necessary, alpha-enolase and its antibody may prove useful in the development of new diagnostic and treatment modalities in BD.

Antibody-dependent NK cell activation is associated with late kidney allograft dysfunction and the complement-independent alloreactive potential of donor-specific antibodies

Directory of Open Access Journals (Sweden)

Tristan Legris

2016-08-01

Full Text Available Although kidney transplantation remains the best treatment for end-stage renal failure, it is limited by chronic humoral aggression of the graft vasculature by donor-specific antibodies (DSAs. The complement-independent mechanisms that lead to the antibody-mediated rejection (ABMR of kidney allografts remain poorly understood. Increasing lines of evidence have revealed the relevance of natural killer (NK cells as innate immune effectors of antibody-dependent cellular cytotoxicity, but few studies have investigated their alloreactive potential in the context of solid organ transplantation. Our study aimed to investigate the potential contribution of the antibody-dependent alloreactive function of NK cells to kidney graft dysfunction. We first conducted an observational study to investigate whether the cytotoxic function of NK cells is associated with chronic allograft dysfunction. The NK-Cellular Humoral Activation Test (NK-CHAT was designed to evaluate the recipient and antibody-dependent reactivity of NK cells against allogeneic target cells. The release of CD107a/Lamp1+ cytotoxic granules, resulting from the recognition of rituximab-coated B cells by NK cells, was analyzed in 148 kidney transplant recipients (KTRs, mean graft duration: 6.2 years. Enhanced ADCC responsiveness was associated with reduced graft function and identified as an independent risk factor predicting a decline in the estimated glomerular filtration rate (eGFR over a 1-year period (hazard ratio: 2.83. In a second approach, we used the NK-CHAT to reveal the cytotoxic potential of circulating alloantibodies in vitro. The level of CD16 engagement resulting from the in vitro recognition of serum-coated allogeneic B cells or splenic cells was further identified as a specific marker of DSA-induced ADCC. The NK-CHAT scoring of sera obtained from 40 patients at the time of transplant biopsy was associated with ABMR diagnosis. Our findings indicate that despite the administration

Cross-reactive Legionella antigens and the antibody response during infection

DEFF Research Database (Denmark)

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

1991-01-01

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

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

Directory of Open Access Journals (Sweden)

Rahul Shukla

2018-01-01

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

Male Partner Risk Behaviors Are Associated With Reactive Rapid HIV Antibody Tests Among Pregnant Mexican Women: Implications for Prevention of Vertical and Sexual HIV Transmission in Concentrated HIV Epidemics.

Science.gov (United States)

Rivero, Estela; Kendall, Tamil

2015-01-01

Mexico's policies on antenatal HIV testing are contradictory, and little is known about social and behavioral characteristics that increase pregnant Mexican women's risks of acquiring HIV. We analyzed the association between risk behaviors reported by pregnant women for themselves and their male partners, and women's rapid HIV antibody test results from a large national sample. Three quarters of pregnant women with a reactive test did not report risk behaviors for themselves and one third did not report risk behaviors for themselves or their male partners. In the retrospective case-control analysis, other than reporting multiple sexual partners, reactive pregnant women reported risk behaviors did not differ from nonreactive women's behaviors. However, reactive pregnant women were significantly more likely to have reported risk behaviors for male partners. Our findings support universal offer of antenatal HIV testing and suggest that HIV prevention for women should focus on reducing risk of HIV acquisition within stable relationships. Copyright © 2015 Association of Nurses in AIDS Care. Published by Elsevier Inc. All rights reserved.

Monoclonal antibody identification of subpopulations of cerebral cortical neurons affected in Alzheimer's disease

International Nuclear Information System (INIS)

Miller, C.A.; Rudnicka, M.; Hinton, D.R.; Blanks, J.C.; Kozlowski, M.

1987-01-01

Neuronal degeneration is one of the hallmarks of Alzheimer's disease (AD). Given the paucity of molecular markers available for the identification of neuronal subtypes, the specificity of neuronal loss within the cerebral cortex has been difficult to evaluate. With a panel of four monoclonal antibodies (mAbs) applied to central nervous system tissues from AD patients, the authors have immunocytochemically identified a population of vulnerable cortical neurons; a subpopulation of pyramidal neurons is recognized by mAbs 3F12 and 44.1 in the hippocampus and neocortex, and clusters of multipolar neurons in the entorhinal cortex reactive with mAb 44.1 show selective degeneration. Closely adjacent stellate-like neurons in these regions, identified by mAb 6A2, show striking preservation in AD. The neurons recognized by mAbs 3F12 and 44.1 do not comprise a single known neurotransmitter system. mAb 3A4 identifies a phosphorylated antigen that is undetectable in normal brain but accumulates early in the course of AD in somas of vulnerable neurons. Antigen 3A4 is distinct from material reactive with thioflavin S or antibody generated against paired helical filaments. Initially, antigen 3A4 is localized to neurons in the entorhinal cortex and subiculum, later in the association neocortex, and, ultimately in cases of long duration, in primary sensory cortical regions. mAb 3F12 recognizes multiple bands of immunoblots of homogenates of normal and AD cortical tissues, whereas mAb 3A4 does not bind to immunoblots containing neurofilament proteins or brain homogenates from AD patients. Ultrastructurally, antigen 3A4 is localized to paired-helical filaments. Using these mAbs, further molecular characterization of the affected cortical neurons is now possible

A malaria vaccine that elicits in humans antibodies able to kill Plasmodium falciparum.

Directory of Open Access Journals (Sweden)

2005-11-01

Full Text Available BACKGROUND: Plasmodium falciparum merozoite surface protein 3 is a malaria vaccine candidate that was identified, characterised, and developed based on a unique immuno-clinical approach. The vaccine construct was derived from regions fully conserved among various strains and containing B cell epitopes targeted by human antibodies (from malaria-immune adults that are able to mediate a monocyte-dependent parasite killing effect. The corresponding long synthetic peptide was administered to 36 volunteers, with either alum or Montanide ISA720 as adjuvant. METHODS AND FINDINGS: Both formulations induced cellular and humoral immune responses. With alum, the responses lasted up to 12 mo. The vaccine-induced antibodies were predominantly of cytophilic classes, i.e., able to cooperate with effector cells. In vitro, the antibodies induced an inhibition of the P. falciparum erythrocytic growth in a monocyte-dependent manner, which was in most instances as high as or greater than that induced by natural antibodies from immune African adults. In vivo transfer of the volunteers' sera into P. falciparum-infected humanized SCID mice profoundly reduced or abrogated parasitaemia. These inhibitory effects were related to the antibody reactivity with the parasite native protein, which was seen in 60% of the volunteers, and remained in samples taken 12 mo postimmunisation. CONCLUSION: This is the first malaria vaccine clinical trial to clearly demonstrate antiparasitic activity by vaccine-induced antibodies by both in vitro and in vivo methods. The results, showing the induction of long-lasting antibodies directed to a fully conserved polypeptide, also challenge current concepts about malaria vaccines, such as unavoidable polymorphism, low antigenicity, and poor induction of immune memory.

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

Science.gov (United States)

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

2013-01-01

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

Determination of specificity and pattern of antinuclear antibodies (ana) in systemic rheumatic disease patients positive for ana testing

International Nuclear Information System (INIS)

Nawaz, H.; Bashir, M.M.; Iqbal, W.

2018-01-01

To determine probability of finding antinuclear antibodies (ANA) and anti extractable nuclear antigens (ENA) positive samples and associating ANA patterns with anti-ENA reactivities among a consecutive cohort of samples of systemic rheumatic disease patients referred for ANA testing. Study Design:Prospective cohort study. Place and Duration of Study:Immunology Department, Armed Forces Institute of Pathology, Rawalpindi, Pakistan, from January to June 2016. Methodology:All the samples referred for ANA testing with clinical suspicion of systemic rheumatic disease were included. After screening, ANA positive samples were subjected to anti-ENA antibodies testing (including anti-SSA, anti-SSB, anti-Sm, anti-RNP, anti-SCL-70 and anti-Jo-1 antibodies) and ANA pattern and titer determination. Results:Of 4,347 samples received, 397 were positive for ANA (9%). Of 397, 96 (24%) samples positive on ENA screen were tested for anti-ENA reactivity. Anti-SSA antibodies were found in 59 samples. Commonest ANA patterns were coarse and fine speckled (43 and 22 samples of 81 tested), while majority of samples carried ANA in titers of 1:40 and 1:80 (22 and 18 samples of 81 tested). No specific ANA pattern was associated with any particular anti-ENA reactivity. Conclusion:Among samples/patients referred for investigations of autoimmune disorders, probability of finding positive ANA is approximately 9%. Of these 9%, about 24% also show reactivity against ENA. Commonest ANA pattern is coarse speckled and majority of such patients carry ANA in titers ranging from 1:40 to 1:80. Commonest ENA reactivity was against SSA. (author)

Cross-reactivity of a polyclonal antibody against Chinemys reevesii vitellogenin with the vitellogenins of other turtle species: Chelydra serpentina , Macrochelys temminckii , and Pelodiscus sinensis.

Science.gov (United States)

Saka, Masahiro; Tada, Noriko; Kamata, Yoichi

2008-09-01

Vitellogenin (VTG), a yolk-precursor protein in oviparous vertebrates, is a useful biomarker for reproductive physiology and environmental estrogenic pollution. To examine interspecific applicability of an enzyme-linked immunosorbent assay (ELISA) for quantifying Chinemys reevesii VTG, we observed cross-reactivity between a polyclonal antibody against Chinemys reevesii VTG and the VTGs from other turtle species: Chelydra serpentina (Chelydridae), Macrochelys temminckii (Chelydridae), and Pelodiscus sinensis (Trionychidae), which are phylogenetically distant from Chinemys reevesii (Geoemydidae). The VTGs of the three species were induced by injecting estradiol 17beta into the turtles and purified by using the EDTA-MgCl(2) precipitation method. The purified VTG appeared as a 200-kDa protein in sodium dodecylsulfate polyacrylamide gel electrophoresis, indicating that the molecular mass of the VTGs of the three species was similar to that of Chinemys reevesii VTG. The purified VTGs were serially diluted (0.004-2 mug/ml) and applied to the ELISA. Although the VTGs of the two chelydrid turtles showed cross-reactivity in a concentration-dependent manner, the degree of cross-reactivity was only 22.8-41.2% (mean=30.0%) and 19.7-53.0% (mean=33.2%) for Chelydra serpentina VTG and Macrochelys temminckii VTG, respectively. The ELISA may therefore be theoretically applicable to measure relative levels of the VTGs of these two species, but the absolute concentration values may be inaccurate. Pelodiscus sinensis VTG showed almost no cross-reactivity (8.0-9.7%, mean=8.9%) at any concentration tested, thus indicating the inapplicability of the ELISA to quantify Pelodiscus sinensis VTG. There are thus limitations in extending the applicability of the ELISA across species, even within the order Testudines.

Neutralization of antibody-enhanced dengue infection by VIS513, a pan serotype reactive monoclonal antibody targeting domain III of the dengue E protein

Science.gov (United States)

Robinson, Luke N.; Ong, Li Ching; Rowley, Kirk J.; Winnett, Alexander; Tan, Hwee Cheng; Hobbie, Sven; Shriver, Zachary; Babcock, Gregory J.; Alonso, Sylvie; Ooi, Eng Eong

2018-01-01

Dengue virus (DENV) infection imposes enormous health and economic burden worldwide with no approved treatment. Several small molecules, including lovastatin, celgosivir, balapiravir and chloroquine have been tested for potential anti-dengue activity in clinical trials; none of these have demonstrated a protective effect. Recently, based on identification and characterization of cross-serotype neutralizing antibodies, there is increasing attention on the potential for dengue immunotherapy. Here, we tested the ability of VIS513, an engineered cross-neutralizing humanized antibody targeting the DENV E protein domain III, to overcome antibody-enhanced infection and high but brief viremia, which are commonly encountered in dengue patients, in various in vitro and in vivo models. We observed that VIS513 efficiently neutralizes DENV at clinically relevant viral loads or in the presence of enhancing levels of DENV immune sera. Single therapeutic administration of VIS513 in mouse models of primary infection or lethal secondary antibody-enhanced infection, reduces DENV titers and protects from lethal infection. Finally, VIS513 administration does not readily lead to resistance, either in cell culture systems or in animal models of dengue infection. The findings suggest that rapid viral reduction during acute DENV infection with a monoclonal antibody is feasible. PMID:29425203

Anti-enrofloxacin antibody production by using enrofloxacin-screened HSA as an immunogen

Science.gov (United States)

Liu, Chune; Lin, Hong; Cao, Limin; Jiang, Jie

2005-07-01

A two-step zero-length cross-linking procedure using active esters was successfully adopted for conjugating enrofloxacin (EF) to human serum albumin (HSA). The derived conjugate was characterized by UV spectrum and then used for immunization of BALB/C mice. In enzyme-linked immunosorbent assay (ELISA) and competitive inhibition ELISA experiments, the derived antiserum exhibited high antibody titer (greater than 1:250 000) as well as varied cross-reactivity (from 97.8% to 161.7%) to three analogs of EF belonging to fluoroquinolones family. But over the concentration range studied, no significant cross-reactivity was observed to other group of antibiotics (chloramphenicol, oxytetracycline, sulphamethoxazole and nysfungin). It was confirmed that the synthesized immunogen was highly antigenic and elicited specific antibody responses in BALB/C mice against EF.

Monoclonal antibodies to molluskan hemocyanin from Concholepas concholepas demonstrate common and specific epitopes among subunits.

Science.gov (United States)

Oliva, Harold; Moltedo, Bruno; De Ioannes, Pablo; Faunes, Fernando; De Ioannes, Alfredo E; Becker, María Inés

2002-10-01

We studied the reactivity of mouse monoclonal antibodies (MAbs) against the hemocyanin from the Chilean marine gastropod Concholepas concholepas (CCH). This protein has been successfully used as a carrier to produce antibodies to haptens and peptides. All MAbs (13) belonging to IgG subclass exhibit dissociation constants (K(d)) from 1 x 10(-7) M to 1 x 10(-9) M. MAbs were characterized by enzyme-linked immunosorbant assay (ELISA) using CCH treated with different procedures, including dissociation into CCH-A and CCH-B subunits, Western blot, enzymatic digestion, chemical deglycosylation, and thermal denaturation. MAbs were classified into three categories, according to subunit specificity by ELISA. The epitope distribution shows that CCH subunits display common epitopes (group I, 5 MAbs, 1H5, 2A8, 3A5, 3B3, and 3E3), as well as specific epitopes for CCH-A subunits (group II, 3 MAbs, 1B8, 4D8, and 8E5) and for CCH-B subunits (group III, 5 MAbs, 1A4, 1E4, 2H10, 3B7, and 7B4). The results can be summarized as follows: (1). six antibodies react with thermal denatured CCH, suggesting that they recognize linear epitopes, whereas seven recognize conformational epitopes; (2). oxidation of carbohydrate moieties does not affect the binding of the MAbs; (3). enzymatic digestion of CCH decreases the reactivity of all antibodies irrespective of the protease used (elastase or trypsin); (4). bringing together the above data, in addition to epitopic complementarity analysis, we identified 12 different epitopes on the CCH molecule recognized by these MAbs. The anti-CCH MAbs presented here can be useful tools to understand the subunit organization of the CCH and its complex structure, which can explain its immunogenic and immunostimulating properties in mammals.

Sero-prevalence of Hepatitis C antibodies in the people visiting roadside barbers

International Nuclear Information System (INIS)

Makheja, K.D.; Abro, A.H.; Kumar, S.

2010-01-01

Sharing of blades and shaving kits, especially unsterilized ones are known risk factors for the transmission of Hepatitis C. The objective of this study was to determine the prevalence of Hepatitis C antibodies reactivity among the patients admitted due to any medical condition and who have been visiting roadside barbers. Methodology: This was a descriptive study conducted from July 2007 to June 2008 in the Medical Unit-111, Jinnah Postgraduate Medical Center, Karachi. The study was designed to include patient's demographics (age, occupation, marital status and education), clinical information and duration of the visits to roadside barbers with an approximate frequency of shavings per month. The patients with history of > 3 visits to a roadside barber during the last six months were included in the study. Whereas, the patients with history of liver disease, blood transfusion, surgery, dental treatment, tattoo marks, intravenous drug use, on regular injectable medicine (like insulin, etc), multiple sexual partners and on haemodialysis were excluded from the study. A blood sample was collected at the time of admission and the screening for HCV-antibodies was done by Enzyme Linked Immuno-Sorbant Assay (ELISA). Results: A total of 184 male patients were included in the study. The mean age + SD of the patients under the study was 33.8+13.2 years. The majority of study patients were uneducated and belonged to low socioeconomic group. Out of 184 patients, 70(38%) were found to be HCV-antibodies reactive. In comparison to younger patients (age <40 years), the older patients as well as those with history of longer duration of visits to roadside barbers had high prevalence of HCV-antibodies reactivity, P.015 and P.02 respectively. There was no statistical significant difference for the prevalence of HCV- antibodies reactivity among the different socioeconomic groups, educational level and marital status. Conclusion: In the present study, it is concluded that the sharing of

An optimized antibody-chelator conjugate for imaging of carcinoembryonic antigen with indium-111

International Nuclear Information System (INIS)

Sumerdon, G.A.; Rogers, P.E.; Lombardo, C.M.; Schnobrich, K.E.; Melvin, S.L.; Tribby, I.I.E.; Stroupe, S.D.; Johnson, D.K.; Hobart, E.D.

1990-01-01

A monoclonal antibody to carcinoembryonic antigen showing minimal cross-reactivity with blood cells and normal tissues was derivatized with benzylisothiocyanate derivatives of EDTA and DTPA. Seven chelators per immunoglobulin could be incorporated without loss of immunoreactivity. The resulting conjugates, labeled with indium-111, showed low liver uptake in animals. A cold kit, comprising the DTPA conjugate at a molarity of antibody bound chelator exceeding 1 x 10 -4 M, gave radiochemical yields of indium labeled antibody of ≥ 95% and was stable for 1 yr. (author)

Analysis of antigenic cross-reactivity between subgroup C avian pneumovirus and human metapneumovirus by using recombinant fusion proteins.

Science.gov (United States)

Luo, L; Sabara, M I; Li, Y

2009-10-01

Avian pneumovirus subgroup C (APV/C) has recently been reported to be more closely related to human metapneumovirus (hMPV) as determined by sequence analysis. To examine the antigenic relationship between APV/C and hMPV, the APV/C fusion (F) gene was cloned and expressed as an uncleaved glycoprotein in a baculovirus system. The reactivity of the APV/C F protein with antibodies against APV subgroups A, B, C, and hMPV was examined by Western blot analysis. The results showed that the expressed APV/C F protein was not only recognized by APV/C-specific antibodies but also by antibodies raised against hMPV. Previously expressed recombinant hMPV F protein also reacted with APV/C-specific antibodies, suggesting that there was significant antigenic cross-reactivity and a potential evolutionary relationship between hMPV and APV/C. Interestingly, the recombinant F proteins from APV/C and hMPV were not recognized by polyclonal antibodies specific to APV subgroups A and B.

Overcoming the Constraints of Anti-HIV/CD89 Bispecific Antibodies That Limit Viral Inhibition

Directory of Open Access Journals (Sweden)

Xiaocong Yu

2016-01-01

Full Text Available Innovative strategies are necessary to maximize the clinical application of HIV neutralizing antibodies. To this end, bispecific constructs of human antibody F240, reactive with well-conserved gp41 epitope and antibody 14A8, reactive with the IgA receptor (CD89 on effector cells, were constructed. A F240 × 14A8 bispecific single chain variable region (scFv molecule was constructed by linking two scFvs using a conventional GGGGS linker. Despite immunoreactivity with HIV gp41 and neutrophils, this bispecific scFv failed to inhibit HIV infection. This is in sharp contrast to viral inhibition using a chemical conjugate of the Fab of these two antibodies. Therefore, we constructed two novel Fab-like bispecific antibody molecules centered on fusion of the IgG1 CH1 domain or CH1-hinge domain to the C-terminus of F240scFv and fusion of the kappa chain CL domain to the C-terminus of 14A8scFv. Both Bi-Fab antibodies showed significant ADCVI activity for multiple clade B and clade C isolates by arming the neutrophils to inhibit HIV infection. The approach presented in this study is unique for HIV immunotherapy in that the impetus of neutralization is to arm and mobilize PMN to destroy HIV and HIV infected cells.

The effects of variations in the specificities of the antibody components on a two-site immunoradiometric assay for ferritin

International Nuclear Information System (INIS)

Cowan, S.I.; Stagg, B.H.; Niemann, E.

1977-01-01

Variations in the sub-unit antigenic structure of ferritins derived from various human tissues are reflected in the differing specificities of antisera raised against these ferritin preparations. In this study it was shown that antibody specificity played an important role in determining the sensitivity and overall binding of labelled antibody in a two-site immunoradiometric assay for ferritin. Homologous assay systems, in which solid phase and radiolabelled antibodies were of similar specificities, were generally less sensitive and showed lower binding than heterologous assay systems, in which solid phase and labelled antibodies were of different specificities. The source of the ferritin which was used as assay standard also played an important part in determining the sensitivity and overall binding in homologous antibody systems, spleen ferritin standards yielding assays superior to those obtained with placenta or liver ferritin standards. However, these differences between standards were not seen in a heterologous system employing solid phase antibodies directed against liver ferritin and labelled antibodies directed against placenta ferritin. The nature of the ferritin used to prepare immunoadsorbant for the purification of antibodies prior to radioiodination also affected the assay characteristics; antibodies prepared on spleen ferritin immunoadsorbant being more reactive than antibodies prepared on placenta ferritin immunoadsorbant, which in turn were more reactive then antibodies prepared on liver ferritin immunoadsorbant. (orig.) [de

Investigating Antivenom Function and Cross-Reactivity – a Study of Antibodies and Their Targets

DEFF Research Database (Denmark)

Engmark, Mikael; De Masi, Federico; Andersen, Mikael Rørdam

species. The active toxin neutralizing components in antivenom are complex mixtures of antibodies (or fragments here of). The individual antibodies are adapted by the immune system of the production animal to bind specific to parts of each toxin used in the immunization procedure. In many cases antivenom...... is also able to neutralize some – or even all – toxic effects of snakebites from related snake species....

Antibodies against Escherichia coli O24 and O56 O-Specific Polysaccharides Recognize Epitopes in Human Glandular Epithelium and Nervous Tissue

Science.gov (United States)

Korzeniowska-Kowal, Agnieszka; Kochman, Agata; Gamian, Elżbieta; Lis-Nawara, Anna; Lipiński, Tomasz; Seweryn, Ewa; Ziółkowski, Piotr; Gamian, Andrzej

2015-01-01

Lipopolysaccharide (LPS), the major component of the outer membrane of Gram-negative bacteria, contains the O-polysaccharide, which is important to classify bacteria into different O-serological types within species. The O-polysaccharides of serotypes O24 and O56 of E. coli contain sialic acid in their structures, already established in our previous studies. Here, we report the isolation of specific antibodies with affinity chromatography using immobilized lipopolysaccharides. Next, we evaluated the reactivity of anti-O24 and anti-O56 antibody on human tissues histologically. The study was conducted under the assumption that the sialic acid based molecular identity of bacterial and tissue structures provides not only an understanding of the mimicry-based bacterial pathogenicity. Cross-reacting antibodies could be used to recognize specific human tissues depending on their histogenesis and differentiation, which might be useful for diagnostic purposes. The results indicate that various human tissues are recognized by anti-O24 and anti-O56 antibodies. Interestingly, only a single specific reactivity could be found in the anti-O56 antibody preparation. Several tissues studied were not reactive with either antibody, thus proving that the presence of cross-reactive antigens was tissue specific. In general, O56 antibody performed better than O24 in staining epithelial and nervous tissues. Positive staining was observed for both normal (ganglia) and tumor tissue (ganglioneuroma). Epithelial tissue showed positive staining, but an epitope recognized by O56 antibody should be considered as a marker of glandular epithelium. The reason is that malignant glandular tumor and its metastasis are stained, and also epithelium of renal tubules and glandular structures of the thyroid gland are stained. Stratified epithelium such as that of skin is definitely not stained. Therefore, the most relevant observation is that the epitope recognized by anti-O56 antibodies is a new marker

Sialylated Autoantigen-Reactive IgG Antibodies Attenuate Disease Development in Autoimmune Mouse Models of Lupus Nephritis and Rheumatoid Arthritis

Directory of Open Access Journals (Sweden)

Yannic C. Bartsch

2018-06-01

Full Text Available Pro- and anti-inflammatory effector functions of IgG antibodies (Abs depend on their subclass and Fc glycosylation pattern. Accumulation of non-galactosylated (agalactosylated; G0 IgG Abs in the serum of rheumatoid arthritis and systemic lupus erythematosus (SLE patients reflects severity of the diseases. In contrast, sialylated IgG Abs are responsible for anti-inflammatory effects of the intravenous immunoglobulin (pooled human serum IgG from healthy donors, administered in high doses (2 g/kg to treat autoimmune patients. However, whether low amounts of sialylated autoantigen-reactive IgG Abs can also inhibit autoimmune diseases is hardly investigated. Here, we explore whether sialylated autoantigen-reactive IgG Abs can inhibit autoimmune pathology in different mouse models. We found that sialylated IgG auto-Abs fail to induce inflammation and lupus nephritis in a B cell receptor (BCR transgenic lupus model, but instead are associated with lower frequencies of pathogenic Th1, Th17 and B cell responses. In accordance, the transfer of small amounts of immune complexes containing sialylated IgG Abs was sufficient to attenuate the development of nephritis. We further showed that administration of sialylated collagen type II (Col II-specific IgG Abs attenuated the disease symptoms in a model of Col II-induced arthritis and reduced pathogenic Th17 cell and autoantigen-specific IgG Ab responses. We conclude that sialylated autoantigen-specific IgG Abs may represent a promising tool for treating pathogenic T and B cell immune responses in autoimmune diseases.

Grass-specific CD4+ T-cells exhibit varying degrees of cross-reactivity, implications for allergen-specific immunotherapy

Science.gov (United States)

Archila, LD; DeLong, JH; Wambre, E; James, EA; Robinson, DM; Kwok, WW

2014-01-01

Background Conceptually, allergic responses may involve cross-reactivity by antibodies or T-cells. While IgE cross-reactivity amongst grass pollen allergens has been observed, cross-reactivity at the allergen-specific T-cell level has been less documented. Identification of the patterns of cross-reactivity may improve our understanding, allowing optimization of better immunotherapy strategies. Objectives We use Phleum pratense as model for the studying of cross-reactivity at the allergen-specific CD4+ T cell level amongst DR04:01 restricted Pooideae grass pollen T-cell epitopes. Methods After In vitro culture of blood mononucleated cells from Grass-pollen allergic subjects with specific Pooideae antigenic epitopes, dual tetramer staining with APC-labeled DR04:01/Phleum pratense tetramers and PE-labeled DR04:01/Pooideae grass homolog tetramers was assessed to identify cross-reactivity amongst allergen-specific DR04:01-restricted T-cells in 6 subjects. Direct ex vivo staining enabled the comparison of frequency and phenotype of different Pooideae grass pollen reactive T-cells. Intracellular cytokine staining (ICS) assays were also used to examine phenotypes of these T-cells. Results T-cells with various degree of cross reactive profiles could be detected. Poa p 1 97-116, Lol p 1 221-240, Lol p 5a 199-218, and Poa p 5a 199-218 were identified as minimally-cross-reactive T-cell epitopes that do not show cross reactivity to Phl p 1 and Phl p 5a epitopes. Ex vivo tetramer staining assays demonstrated T-cells that recognized these minimally-cross reactive T-cell epitopes are present in Grass-pollen allergic subjects. Conclusions Our results suggest that not all Pooideae grass epitopes with sequence homology are cross-reactive. Non-cross reactive T-cells with comparable frequency, phenotype and functionality to Phl p-specific T-cells, suggest that a multiple allergen system should be considered for immunotherapy instead of a mono allergen system. PMID:24708411

Grass-specific CD4(+) T-cells exhibit varying degrees of cross-reactivity, implications for allergen-specific immunotherapy.

Science.gov (United States)

Archila, L D; DeLong, J H; Wambre, E; James, E A; Robinson, D M; Kwok, W W

2014-07-01

Conceptually, allergic responses may involve cross-reactivity by antibodies or T-cells. While IgE cross-reactivity among grass-pollen allergens has been observed, cross-reactivity at the allergen-specific T-cell level has been less documented. Identification of the patterns of cross-reactivity may improve our understanding, allowing optimization of better immunotherapy strategies. We use Phleum pratense as model for the studying of cross-reactivity at the allergen-specific CD4(+) T cell level among DR04:01 restricted Pooideae grass-pollen T-cell epitopes. After in vitro culture of blood mono-nucleated cells from grass-pollen-allergic subjects with specific Pooideae antigenic epitopes, dual tetramer staining with APC-labelled DR04:01/Phleum pratense tetramers and PE-labelled DR04:01/Pooideae grass homolog tetramers was assessed to identify cross-reactivity among allergen-specific DR04:01-restricted T-cells in six subjects. Direct ex vivo staining enabled the comparison of frequency and phenotype of different Pooideae grass-pollen reactive T-cells. Intracellular cytokine staining (ICS) assays were also used to examine phenotypes of these T-cells. T-cells with various degrees of cross-reactive profiles could be detected. Poa p 1 97-116 , Lol p 1 221-240 , Lol p 5a 199-218 , and Poa p 5a 199-218 were identified as minimally cross-reactive T-cell epitopes that do not show cross-reactivity to Phl p 1 and Phl p 5a epitopes. Ex vivo tetramer staining assays demonstrated T-cells that recognized these minimally cross-reactive T-cell epitopes are present in Grass-pollen-allergic subjects. Our results suggest that not all Pooideae grass epitopes with sequence homology are cross-reactive. Non-cross-reactive T-cells with comparable frequency, phenotype and functionality to Phl p-specific T-cells suggest that a multiple allergen system should be considered for immunotherapy instead of a mono-allergen system. © 2014 John Wiley & Sons Ltd.

Llama Single Domain Antibodies Specific for the 7 Botulinum Neurotoxin Serotypes as Heptaplex Immunoreagents

Science.gov (United States)

Collazo, M. Thelma; Garza, John A.; Hayhurst, Andrew

2010-01-01

Background There are currently 7 known serotypes of botulinum neurotoxin (BoNT) classified upon non-cross reactivity of neutralizing immunoglobulins. Non-neutralizing immunoglobulins, however, can exhibit cross-reactivities between 2 or more serotypes, particularly mosaic forms, which can hamper the development of highly specific immunoassays, especially if based on polyclonal antisera. Here we employ facile recombinant antibody technology to subtractively select ligands to each of the 7 BoNT serotypes, resulting in populations with very high specificity for their intended serotype. Methods and Findings A single llama was immunized with a cocktail of 7 BoNT toxoids to generate a phage display library of single domain antibodies (sdAb, VHH or nanobodies) which were selected on live toxins. Resulting sdAb were capable of detecting both toxin and toxin complex with the best combinations able to detect 100s-10s of pg per 50 µL sample in a liquid bead array. The most sensitive sdAb were combined in a heptaplex assay to identify each of the BoNT serotypes in buffer and milk and to a lesser extent in carrot juice, orange juice and cola. Several anti-A(1) sdAb recognized A2 complex, showing that subtype cross-reactivity within a serotype was evident. Many of our sdAb could act as both captor and tracer for several toxin and toxin complexes suggesting sdAb can be used as architectural probes to indicate BoNT oligomerisation. Six of 14 anti-A clones exhibited inhibition of SNAP-25 cleavage in the neuro-2A assay indicating some sdAb had toxin neutralizing capabilities. Many sdAb were also shown to be refoldable after exposure to high temperatures in contrast to polyclonal antisera, as monitored by circular dichroism. Conclusions Our panel of molecularly flexible antibodies should not only serve as a good starting point for ruggedizing assays and inhibitors, but enable the intricate architectures of BoNT toxins and complexes to be probed more extensively. PMID:20098614

Anti-phosphatidylserine/prothrombin antibodies: an additional diagnostic marker for APS?

Science.gov (United States)

Pregnolato, Francesca; Chighizola, Cecilia B; Encabo, Susan; Shums, Zakera; Norman, Gary L; Tripodi, Armando; Chantarangkul, Veena; Bertero, Tiziana; De Micheli, Valeria; Borghi, Maria Orietta; Meroni, Pier Luigi

2013-07-01

Among the diagnostic assays for anti-phospholipid syndrome (APS), lupus anticoagulant (LA) is the strongest predictor of thrombosis; however, it presents several limitations as interference with anticoagulant therapy and poor inter-laboratory agreement. Two-thirds of LA activity is apparently due to antibodies against prothrombin (PT), usually detectable by ELISA. Binding of PT to phosphatidylserine (PS) has been shown to enhance solid-phase anti-PT assay sensitivity. To determine the prevalence of antibodies against PS/PT (aPS/PT) in APS, we tested the semiquantitative QUANTA Lite(®) aPS/PT ELISA in a cohort of 80 APS patients. The prevalence of aPS/PT was 81.3%, rising to 87.6% when considering LA-positive subjects only. We observed a strong correlation between aPS/PT and LA (p = 0.006). To note, APS patients with thrombotic manifestations displayed significantly higher IgG aPS/PT titers compared to 20 aPL asymptomatic carriers (p = 0.012). To rule out a possible cross-reactivity of anti-β2 glycoprotein I antibodies (aβ2GPI) with PS/PT complex, we tested two monoclonal aβ2GPI antibodies and an affinity-purified (AP) polyclonal aβ2GPI IgG obtained from the serum of a patient reacting against both β2GPI and PS/PT. The two monoclonal antibodies did not show any reactivity against PS/PT complex, similarly the AP IgGs did not react toward PS/PT antigen while preserved their aβ2GPI activity. Our findings suggest that aPS/PT are a definite antibody population in APS. Moreover, the good correlation between aPS/PT ELISA and LA may support its use as a surrogate test for LA, particularly useful to overcome the technical limitations of the functional assay.

Brain antibodies in the cortex and blood of people with schizophrenia and controls.

Science.gov (United States)

Glass, L J; Sinclair, D; Boerrigter, D; Naude, K; Fung, S J; Brown, D; Catts, V S; Tooney, P; O'Donnell, M; Lenroot, R; Galletly, C; Liu, D; Weickert, T W; Shannon Weickert, C

2017-08-08

The immune system is implicated in the pathogenesis of schizophrenia, with elevated proinflammatory cytokine mRNAs found in the brains of ~40% of individuals with the disorder. However, it is not clear if antibodies (specifically immunoglobulin-γ (IgG)) can be found in the brain of people with schizophrenia and if their abundance relates to brain inflammatory cytokine mRNA levels. Therefore, we investigated the localization and abundance of IgG in the frontal cortex of people with schizophrenia and controls, and the impact of proinflammatory cytokine status on IgG abundance in these groups. Brain IgGs were detected surrounding blood vessels in the human and non-human primate frontal cortex by immunohistochemistry. IgG levels did not differ significantly between schizophrenia cases and controls, or between schizophrenia cases in 'high' and 'low' proinflammatory cytokine subgroups. Consistent with the existence of IgG in the parenchyma of human brain, mRNA and protein of the IgG transporter (FcGRT) were present in the brain, and did not differ according to diagnosis or inflammatory status. Finally, brain-reactive antibody presence and abundance was investigated in the blood of living people. The plasma of living schizophrenia patients and healthy controls contained antibodies that displayed positive binding to Rhesus macaque cerebellar tissue, and the abundance of these antibodies was significantly lower in patients than controls. These findings suggest that antibodies in the brain and brain-reactive antibodies in the blood are present under normal circumstances.

Patterned immobilization of antibodies within roll-to-roll hot embossed polymeric microfluidic channels.

Directory of Open Access Journals (Sweden)

Belachew Feyssa

Full Text Available This paper describes a method for the patterned immobilization of capture antibodies into a microfluidic platform fabricated by roll-to-roll (R2R hot embossing on poly (methyl methacrylate (PMMA. Covalent attachment of antibodies was achieved by two sequential inkjet printing steps. First, a polyethyleneimine (PEI layer was deposited onto oxygen plasma activated PMMA foil and further cross-linked with glutaraldehyde (GA to provide an amine-reactive aldehyde surface (PEI-GA. This step was followed by a second deposition of antibody by overprinting on the PEI-GA patterned PMMA foil. The PEI polymer ink was first formulated to ensure stable drop formation in inkjet printing and the printed films were characterized using atomic force microscopy (AFM and X-ray photoelectron spectroscopy (XPS. Anti-CRP antibody was patterned on PMMA foil by the developed method and bonded permanently with R2R hot embossed PMMA microchannels by solvent bonding lamination. The functionality of the immobilized antibody inside the microfluidic channel was evaluated by fluorescence-based sandwich immunoassay for detection of C-reactive protein (CRP. The antibody-antigen assay exhibited a good level of linearity over the range of 10 ng/ml to 500 ng/ml (R(2 = 0.991 with a calculated detection limit of 5.2 ng/ml. The developed patterning method is straightforward, rapid and provides a versatile approach for creating multiple protein patterns in a single microfluidic channel for multiplexed immunoassays.

Evaluation of the Cross-reactivity of Antidrug Antibodies to CT-P13 and Infliximab Reference Product (Remicade): An Analysis Using Immunoassays Tagged with Both Agents.

Science.gov (United States)

Reinisch, Walter; Jahnsen, Jørgen; Schreiber, Stefan; Danese, Silvio; Panés, Julián; Balsa, Alejandro; Park, Won; Kim, JiSoo; Lee, Jee Un; Yoo, Dae Hyun

2017-06-01

During two pivotal clinical trials of the infliximab biosimilar CT-P13 (PLANETAS and PLANETRA), antidrug antibodies (ADAs) and neutralising antibodies (NAbs) were detected in the sera of patients treated with CT-P13 and the reference product (RP; Remicade). The aim was to assess the comparability of Remicade- and CT-P13-tagged immunoassays for the detection of ADAs and NAbs using data from these trials, in order to determine the cross-reactivity of CT-P13 and RP ADAs. Sera from patients with rheumatoid arthritis and ankylosing spondylitis were analysed using an electrochemiluminescence (ECL) bridging assay or Gyros immunoassay, tagged with Remicade or CT-P13 at screening, weeks 14, 30 and 54, and the end of study visit. NAb titre was compared at screening and weeks 14 and 30. The proportion of cross-reactive samples was determined and an inter-rater agreement analysis performed to assess the concordance of results between assays. In PLANETAS, 93.1% (94/101) of RP ADA-positive samples and 93.0% (93/100) of RP NAb-positive samples cross-reacted with CT-P13; 99.0% (103/104) of CT-P13 ADA-positive and 98.0% (98/100) of CT-P13 NAb-positive samples cross-reacted with the RP. In PLANETRA, 94.7% (426/450) of RP ADA-positive samples and 94.3% (415/440) of RP NAb-positive samples cross-reacted with CT-P13, and 96.6% (458/474) of CT-P13 ADA-positive and 96.4% (452/469) of CT-P13 NAb-positive samples cross-reacted with the RP. In both studies, there was strong agreement in outcome between assays at all post-screening time points (PLANETAS: Cohen's κ 0.89-0.98 for ADA, 0.86-0.98 for NAb; PLANETRA: 0.92-0.94 for both ADA and NAb, all p PLANETAS: Spearman's ρ 0.73 and 0.74, respectively; PLANETRA: 0.61 and 0.72, respectively; all p < 0.001). This study has demonstrated that ADAs and NAbs against CT-P13 and RP are cross-reactive, indicating that CT-P13 and RP share immunodominant epitopes.

Spectrum of antibody profiles in tuberculous elephants, cervids, and cattle.

Science.gov (United States)

Lyashchenko, Konstantin P; Gortázar, Christian; Miller, Michele A; Waters, W Ray

2018-02-01

Using multi-antigen print immunoassay and DPP ® VetTB Assay approved in the United States for testing captive cervids and elephants, we analyzed antibody recognition of MPB83 and CFP10/ESAT-6 antigens in Asian elephants (Elephas maximus) infected with Mycobacterium tuberculosis and in white-tailed deer (Odocoileus virginianus), fallow deer (Dama dama), elk (Cervus elaphus), and cattle (Bos taurus) infected with Mycobacterium bovis. Serum IgG reactivity to MPB83 was found in the vast majority of tuberculous cattle and cervid species among which white-tailed deer and elk also showed significant CFP10/ESAT-6 recognition rates with added serodiagnostic value. In contrast, the infected elephants developed antibody responses mainly to CFP10/ESAT-6 with MPB83 reactivity being relatively low. The findings demonstrate distinct patterns of predominant antigen recognition by different animal hosts in tuberculosis. Copyright © 2017 Elsevier B.V. All rights reserved.

Ma2 antibodies: an evaluation of commercially available detection methods.

Science.gov (United States)

Johannis, Wibke; Renno, Joerg H; Wielckens, Klaus; Voltz, Raymond

2011-01-01

Ma2 antibodies belong to the onconeuronal antibodies which define a "definite" paraneoplastic neurological syndrome (PNS). Because of the clinical relevance, use of two separate methods (indirect immunofluorescence technique--IFT--and immunoblot) is advocated; however, with an increasing number of commercially available assay systems, usually only one assay is performed. We compared IFT and three commercially available immunoblots (ravo Diagnostika, Euroimmun, Milenia Biotec) on sera from 35 patients with clinically suspected PNS. 17 were Ma2 antibody associated as defined by consensus result (showing positive reactivity in 2 assays), 18 were Ma2 antibody negative controls. Sensitivity/specificity for single assays were for IFT 94%/94%, for ravo Diagnostika PNS blot 88%/100%, for Euroimmun Neuronal Antigens Profile blot 100%/89%, and for Milenia Biotec MTR blot 94%/100%. Our data confirm, although all tests performed well, a combination of 2 independent assays is still advisable for Ma2 antibody detection in order to achieve higher sensitivity and specificity rates.

Co-Positivity for Anti-dsDNA, -Nucleosome and -Histone Antibodies in Lupus Nephritis Is Indicative of High Serum Levels and Severe Nephropathy.

Directory of Open Access Journals (Sweden)

Jinfeng Yang

Full Text Available To characterize the significance of correlated autoantibodies in systemic lupus erythematosus (SLE and its complication lupus nephritis (LN in a large cohort of patients.Clinical data were statistically analyzed in 1699 SLE patients with or without nephritis who were diagnosed and treated during 2002-2013 in the northeast region of China. Reactivity to a list of 16 autoantibodies was detected by the serum test Euroline ANA profile (IgG. Serum titers of the anti-nucleosome autoantibodies were measured by ELISA assays. Kidney biopsies were examined by pathologists. Immune complex deposition was identified by immunohistochemistry stain.Simultaneous positivity of anti-dsDNA, -nucleosome and -histone antibodies (3-pos was prevalent in SLE patients with LN compared to Non-renal SLE patients (41% vs 11%, p< 0.001. Significant correlations were found between any two of the above three anti-nucleosome antibodies in LN patients. In comparison to non-3-pos cohorts, 3-pos patients with LN had significantly higher serum levels of the three antibodies and more active disease; was associated with type IV disease; suffered from more severe renal damages; received more intensive treatment and had worse disease outcome. The serum levels of these three autoantibodies in 3-pos LN patients were significantly decreased when they underwent clinical recovery.Simultaneous reactivity to anti-dsDNA, -nucleosome and -histone antibodies by Euroline ANA profile (IgG may indicate severe nephropathy in patients with SLE.

Observed Parent-Child Relationship Quality Predicts Antibody Response to Vaccination in Children

Science.gov (United States)

O'Connor, Thomas G; Wang, Hongyue; Moynihan, Jan A; Wyman, Peter A.; Carnahan, Jennifer; Lofthus, Gerry; Quataert, Sally A.; Bowman, Melissa; Burke, Anne S.; Caserta, Mary T

2015-01-01

Background Quality of the parent-child relationship is a robust predictor of behavioral and emotional health for children and adolescents; the application to physical health is less clear. Methods We investigated the links between observed parent-child relationship quality in an interaction task and antibody response to meningococcal conjugate vaccine in a longitudinal study of 164 ambulatory 10-11 year-old children; additional analyses examine associations with cortisol reactivity, BMI, and somatic illness. Results Observed negative/conflict behavior in the interaction task predicted a less robust antibody response to meningococcal serotype C vaccine in the child over a 6 month-period, after controlling for socio-economic and other covariates. Observer rated interaction conflict also predicted increased cortisol reactivity following the interaction task and higher BMI, but these factors did not account for the link between relationship quality and antibody response. Conclusions The results begin to document the degree to which a major source of child stress exposure, parent-child relationship conflict, is associated with altered immune system development in children, and may constitute an important public health consideration. PMID:25862953

High Concentrations of Measles Neutralizing Antibodies and High-Avidity Measles IgG Accurately Identify Measles Reinfection Cases

Science.gov (United States)

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

Antigenic specificity of serum antibodies in mice fed soy protein

DEFF Research Database (Denmark)

Christensen, Hanne Risager; Bruun, S.W.; Frøkiær, Hanne

2003-01-01

Background: Soybean protein is used in a number of food products but unfortunately is also a common cause of food allergy. Upon ingestion of soy protein, healthy mice like other animals and humans generate a soy-specific antibody response in the absence of signs of illness. Not much is known about...... the relationship between the immunogenic proteins involved in this nondeleterious antibody response and the pathological response associated with food allergy. The objective of the present study was to characterize the antigenic specificity of the soy protein-specific antibody response generated in healthy mice...... ingesting soy protein. Methods: Blood from mice fed a soy-containing diet was analyzed using ELISA and immunoblot for antibody reactivity towards various soy protein fractions and pure soy proteins/subunits. Mice bred on a soy-free diet were used as controls. Results: The detectable antigenic specificity...

Nucleotide sequences of the cDNAs encoding the V-regions of H- and L-chains of a human monoclonal antibody with broad reactivity to malignant tumor cells

Energy Technology Data Exchange (ETDEWEB)

Kishimoto, Toshimitsu; Okajima, Hideki; Okumoto, Takeki [Yoshitomi Pharmaceutical Industries, Ltd., Saitama (Japan); Taniguchi, Masaru [Chiba Univ. (Japan)

1989-06-12

The human monoclonal antibody secreted from 4G12 hybridoma cells has broad reactivity to malignant tumor cells, especially for lung squamous cell carcinomas, and recognizes a new tumor-associated and differentiation antigen. The antigen detected by 4G12 is a glycoprotein with MW 195,000 and MW 65,000 under nonreducing and reducing conditions, respectively. Screening of a 4G12 {lambda}gt10 cDNA library with constant region probes for human immunoglobulin yielded full length clones for H- and L-chains. Nucleotide sequences revealed that subtypes of the variable regions were V{sub HIII} and {lambda}{sub 1}, respectively.

Considerations for the nonclinical safety evaluation of antibody drug conjugates for oncology.

Science.gov (United States)

Roberts, Stanley A; Andrews, Paul A; Blanset, Diann; Flagella, Kelly M; Gorovits, Boris; Lynch, Carmel M; Martin, Pauline L; Kramer-Stickland, Kimberly; Thibault, Stephane; Warner, Garvin

2013-12-01

Antibody drug conjugates (ADCs) include monoclonal antibodies that are linked to cytotoxic small molecules. A number of these agents are currently being developed as anti-cancer agents designed to improve the therapeutic index of the cytotoxin (i.e., cytotoxic small molecule or cytotoxic agent) by specifically delivering it to tumor cells. This paper presents primary considerations for the nonclinical safety evaluation of ADCs and includes strategies for the evaluation of the entire ADC or the various individual components (i.e., antibody, linker or the cytotoxin). Considerations are presented on how to design a nonclinical safety assessment program to identify the on- and off-target toxicities to enable first-in-human (FIH) studies. Specific discussions are also included that provide details as to the need and how to conduct the studies for evaluating ADCs in genetic toxicology, tissue cross-reactivity, safety pharmacology, carcinogenicity, developmental and reproductive toxicology, biotransformation, toxicokinetic monitoring, bioanalytical assays, immunogenicity testing, test article stability and the selection of the FIH dose. Given the complexity of these molecules and our evolving understanding of their properties, there is no single all-encompassing nonclinical strategy. Instead, each ADC should be evaluated on a case-by-case scientifically-based approach that is consistent with ICH and animal research guidelines. Copyright © 2013 Elsevier Inc. All rights reserved.

Isolation of human anti-serum albumin Fab antibodies with an extended serum-half life.

Science.gov (United States)

Kang, Hyeon-Ju; Kim, Hye-Jin; Cha, Sang-Hoon

2016-01-01

The serum albumin (SA) has been exploited to generate long-acting biotherapeutics by taking advantage of the FcRn-mediated recycling mechanism in a direct or an indirect way. Since Fab fragments have been proven to be clinically safe for human usage, we assumed that human anti-SA Fab antibodies could have a great potential as a carrier molecule to extend the serum half-life of therapeutic proteins. We, herein, had attempted to isolate anti-SA Fab antibodies from HuDVFab-8L antibody library via a phage display technology, and identified eight discrete human Fab antibodies. One of the Fab antibodies, SL335, showed the strongest binding reactivity to human SA with nM range of affinity at both pH 6 and pH 7.4, and cross-reacted to SAs from various species including rat, mouse, canine and monkey. The in vivo pharmacokinetic assay using a rat model indicated that SL335 has approximately 10 fold longer serum half-life and 26 to 44-fold increase in AUC0 → ∞ compared to the negative control Fab molecule in both intravenous and subcutaneous administrations. Knowing that Fabs have proven to be safe in clinics for a long time, SL335 seems to have a great potential in generating long-acting protein drugs by tagging effector molecules with either chemical conjugation or genetic fusion. Copyright © 2015 Elsevier B.V. All rights reserved.

Anticarbohydrate Antibody Repertoires in Patients Transplanted with Fetal Pig Islets Revealed by Glycan Arrays

DEFF Research Database (Denmark)

Blixt, Klas Ola; Kumagai-Braesch, A.; Tibell, A.

2009-01-01

Ten patients with type I diabetes were transplanted with porcine fetal islet-like cell clusters (ICC) between 1990 and 1993. A significant rise in the anti-a-Gal antibody titers was seen posttransplant, but also non-a-Gal-specific antibodies were detected in some patients. We have reanalyzed...... the carbohydrate specificity of antibodies in the sera from seven of these patients taken before transplantation, 1, 6 and 12 months posttransplantation using a glycan array with 200 structurally defined glycans. The main findings were: (i) prepig ICC transplantation patients had antibodies reactive with terminal...... compounds; (ii) the titers of all carbohydrate-specific antibodies detected before transplantation rose after transplantation; (iii) the kinetics of the antibody responses differed between patients; (iv) in some patients antibodies reacting with Gala1,3Lex and several structures terminated with Neu5Gc...

Physical characteristics of a citrullinated pro-filaggrin epitope recognized by anti-citrullinated protein antibodies in rheumatoid arthritis sera

DEFF Research Database (Denmark)

Trier, Nicole Hartwig; Holm, Bettina Eide; Slot, Ole

2016-01-01

whether biotin labelling influence antibody recognition. The full-length cyclic pro-filaggrin peptide and a linear form with a N-terminal biotin, was recognized to the same level, whereas, a notable difference in ACPA reactivity to the linear peptides with a C-terminal biotin was found, probably due...... amino acid in position 4 C-terminal to citrulline. Collectively, peptide structure, length, the presence of charged amino acids and biotin labelling markedly influence antibody reactivity. In relation to the clinical diagnostics of ACPA, these findings may reflect the differences in diagnostic assays...

HIV‑2 antibody detection after indeterminate or negative HIV‑1 Western blot in Cuba, 2005-2008.

Science.gov (United States)

Díaz, Dervel F; Ortiz, Eva; Martín, Dayamí; Nibot, Carmen; Rizo, Adis; Silva, Eladio

2012-01-01

INTRODUCTION Differentiating between HIV-1 and HIV-2 infection is the first step to understanding HIV transmission, epidemiology and pathogenesis in geographical areas where both viruses circulate. In Cuba, positive results in mixed HIV-1/2 screening assays are confirmed by HIV-1 Western blot. Indeterminate results constitute the main limitation of this test and HIV-2 infection is among their possible causes; hence the importance of second-stage screening and confirmatory tests for HIV-2 infection. OBJECTIVE Investigate the contribution of HIV-2 antibodies to negative or indeterminate HIV-1 Western blot results in serum samples from 2005 through 2008 in Cuba. METHODS HIV-2 reactivity was studied using the ELISA DAVIH-VIH-2 diagnostic kit (Cuba) in 1723 serum samples with negative or indeterminate results for HIV-1 Western blot from January 2005 through December 2008. Duplicate sera reactive by ELISA were confirmed by HIV-2 Western blot, results interpreted according to WHO criteria. The epidemiological interview established by Cuba's National Program for Prevention and Control Sexually-Transmitted Diseases and HIV/AIDS was applied to HIV-2 Western blot-positive patients. RESULTS Among all sera studied, HIV-2 ELISA identified 12 reactive serum samples (0.70%) and 1711 non-reactive (99.30%). Western blot analysis of the 12 ELISA-reactive samples confirmed two positive samples (16.67%), 4 negative (33.33%) and 6 indeterminate (50%). Positive samples reacted against the p16, p26, gp36, p53, p56, p68 and gp105 proteins. All 12 ELISA-reactive samples belonged to the HIV-1 Western blot indeterminate group. The two HIV-2-positive samples showed well defined reactivity to gp160, p53, p55 and p34 of HIV-1. HIV-1 seroconversion was observed in all 10 remaining samples during serological followup. CONCLUSIONS Two new HIV-2 seropositive cases were diagnosed using DAVIH-VIH-2 and HIV-2 Western blot in indeterminate HIV-1 Western blot samples. Results support the recommendation

Greek rheumatoid arthritis patients have elevated levels of antibodies against antigens from Proteus mirabilis.

Science.gov (United States)

Christopoulos, Georgios; Christopoulou, V; Routsias, J G; Babionitakis, A; Antoniadis, C; Vaiopoulos, G

2017-03-01

Patients with rheumatoid arthritis (RA) from different ethnic groups present elevated levels of antibodies against Proteus mirabilis. This finding implicates P. mirabilis in the development of RA. The aim of this study was to investigate the importance of P. mirabilis in the etiopathogenesis of RA in Greek RA patients. In this study, 63 patients with RA and 38 healthy controls were included. Class-specific antibodies IgM, IgG, and IgA against three human cross-reactive and non-cross-reactive synthetic peptides from P. mirabilis-hemolysin (HpmB), urease C (UreC), and urease F (UreF)-were performed in all subjects, using the ELISA method. RA patients had elevated levels of IgM, IgG, and IgA antibodies against HpmB and UreC Proteus peptide which are significantly different compared to healthy controls: p = 0.005, p Proteus peptide-which are non-cross-reactive with human tissue antigens-were observed and their significant difference compared to healthy controls (p = 0.007, p mirabilis antigenic epitopes, such as in North European populations, albeit Greek RA patients presenting the cross-reaction antigen in a low percentage. These results indicate that P. mirabilis through the molecular mimicry mechanism leads to inflammation and damage of the joints in RA.

Anti-Thyroid Peroxidase Reactivity Is Heightened in Pemphigus Vulgaris and Is Driven by Human Leukocyte Antigen Status and the Absence of Desmoglein Reactivity

Directory of Open Access Journals (Sweden)

Kristina Seiffert-Sinha

2018-04-01

Full Text Available Pemphigus vulgaris (PV belongs to an autoimmune disease cluster that includes autoimmune thyroid disease (AITD, suggesting common mechanisms driving autoimmune susceptibility. Our group has shown that PV patients exhibit significant reactivity to AITD-related anti-thyroid peroxidase (anti-TPO, and anti-TPO antibodies affect signaling pathways in keratinocytes similar to anti-desmoglein (Dsg 3 antibodies. To further assess the relevance of anti-TPO reactivity in PV, we analyzed anti-TPO levels in 280 PV and 167 healthy control serum samples across a comprehensive set of variable and static parameters of disease activity and etiopathogenesis. PV patients have significantly higher activity rates (A.R.s for anti-TPO than healthy controls, but levels do not differ between phases of clinical activity and remission. Patients that carry both the PV-associated human leukocyte antigen (HLA alleles DRB1*0402 and DQB1*0503, or DQB1*0503 alone show a low prevalence of anti-TPO (A.R. 9.5 and 4.8%, respectively, while patients that lack expression of these alleles or carry DRB1*0402 alone have a much higher prevalence of anti-TPO (A.R. 23.1 and 15.8%, respectively, suggesting that the absence of DQB1*0503 may predispose patients to the development of anti-TPO antibodies. Similarly, anti-Dsg1−/3− patients have a higher anti-TPO A.R. (26.9% than anti-Dsg1−/3+ (18.8%, anti-Dsg1+/3− (14.3%, and anti-Dsg1+/3+ (3.9% patients. Our data suggest that anti-TPO reactivity in PV is driven by genetic markers that may be in linkage disequilibrium with the established PV-susceptibility alleles and that this association drives the selection of a combination of anti-Dsg and anti-TPO antibodies, with anti-TPO filling the gap in active patients that do not carry the established PV-associated autoantibodies and/or are lacking the established PV-HLA-susceptibility alleles.

Anti-Thyroid Peroxidase Reactivity Is Heightened in Pemphigus Vulgaris and Is Driven by Human Leukocyte Antigen Status and the Absence of Desmoglein Reactivity

Science.gov (United States)

Seiffert-Sinha, Kristina; Khan, Shahzaib; Attwood, Kristopher; Gerlach, John A.; Sinha, Animesh A.

2018-01-01

Pemphigus vulgaris (PV) belongs to an autoimmune disease cluster that includes autoimmune thyroid disease (AITD), suggesting common mechanisms driving autoimmune susceptibility. Our group has shown that PV patients exhibit significant reactivity to AITD-related anti-thyroid peroxidase (anti-TPO), and anti-TPO antibodies affect signaling pathways in keratinocytes similar to anti-desmoglein (Dsg) 3 antibodies. To further assess the relevance of anti-TPO reactivity in PV, we analyzed anti-TPO levels in 280 PV and 167 healthy control serum samples across a comprehensive set of variable and static parameters of disease activity and etiopathogenesis. PV patients have significantly higher activity rates (A.R.s) for anti-TPO than healthy controls, but levels do not differ between phases of clinical activity and remission. Patients that carry both the PV-associated human leukocyte antigen (HLA) alleles DRB1*0402 and DQB1*0503, or DQB1*0503 alone show a low prevalence of anti-TPO (A.R. 9.5 and 4.8%, respectively), while patients that lack expression of these alleles or carry DRB1*0402 alone have a much higher prevalence of anti-TPO (A.R. 23.1 and 15.8%, respectively), suggesting that the absence of DQB1*0503 may predispose patients to the development of anti-TPO antibodies. Similarly, anti-Dsg1−/3− patients have a higher anti-TPO A.R. (26.9%) than anti-Dsg1−/3+ (18.8%), anti-Dsg1+/3− (14.3%), and anti-Dsg1+/3+ (3.9%) patients. Our data suggest that anti-TPO reactivity in PV is driven by genetic markers that may be in linkage disequilibrium with the established PV-susceptibility alleles and that this association drives the selection of a combination of anti-Dsg and anti-TPO antibodies, with anti-TPO filling the gap in active patients that do not carry the established PV-associated autoantibodies and/or are lacking the established PV-HLA-susceptibility alleles. PMID:29675021

Human antibody and antigen response to IncA antibody of Chlamydia trachomatis.

Science.gov (United States)

Tsai, P Y; Hsu, M C; Huang, C T; Li, S Y

2007-01-01

The high prevalence of C. trachomatis worldwide has underscored the importance of identifying specific immunogenic antigens in facilitating diagnosis as well as vaccine development. The aim of this study is to evaluate IncA antibody and antigen production in natural human infections. Our temporal expression study showed that IncA transcription and protein expression could be detected as early as 4 hours after the start of infection. Antibody responses could be detected in urine and genital swab samples from C. trachomatis-positive patients. It is especially interesting to note that the IncA antigen could be detected in urine. In conclusion, we have identified IncA as an important antigen in human. The potential applicability of the IncA antibody or antigen in the diagnosis as well as to vaccine development for C. trachomatis is also discussed.

Detection of antibodies against Paracoccidioides brasiliensis melanin in in vitro and in vivo studies during infection.

Science.gov (United States)

Urán, Martha E; Nosanchuk, Joshua D; Restrepo, Angela; Hamilton, Andrew J; Gómez, Beatriz L; Cano, Luz E

2011-10-01

Several cell wall constituents, including melanins or melanin-like compounds, have been implicated in the pathogenesis of a wide variety of microbial diseases caused by diverse species of pathogenic bacteria, fungi, and helminthes. Among these microorganisms, the dimorphic fungal pathogen Paracoccidioides brasiliensis produces melanin in its conidial and yeast forms. In the present study, melanin particles from P. brasiliensis were injected into BALB/c mice in order to produce monoclonal antibodies (MAbs). We identified five immunoglobulin G1 (IgG1) κ-chain and four IgM melanin-binding MAbs. The five IgG1 κ-chain isotypes are the first melanin-binding IgG MAbs ever reported. The nine MAbs labeled P. brasiliensis conidia and yeast cells both in vitro and in pulmonary tissues. The MAbs cross-reacted with melanin-like purified particles from other fungi and also with commercial melanins, such as synthetic and Sepia officinalis melanin. Melanization during paracoccidioidomycosis (PCM) was also further supported by the detection of IgG antibodies reactive to melanin from P. brasiliensis conidia and yeast in sera and bronchoalveolar lavage fluids from P. brasiliensis-infected mice, as well as in sera from human patients with PCM. Serum specimens from patients with other mycoses were also tested for melanin-binding antibodies by enzyme-linked immunosorbent assay, and cross-reactivities were detected for melanin particles from different fungal sources. These results suggest that melanin from P. brasiliensis is an immunologically active fungal structure that activates a strong IgG humoral response in humans and mice.

Antilymphocytic antibodies and marrow transplantation. VIII. Recipient conditioning with Clq-affine monoclonal anti-pan T antibodies prevents GVHD in homozygous fully mismatched mice

International Nuclear Information System (INIS)

Thierfelder, S.; Kummer, U.; Schuh, R.; Mysliwietz, J.

1986-01-01

An approach to suppressing secondary disease with antibodies was studied that differed from conventional antibody treatment of donor marrow in vitro. It consisted of the selection of anti-Thy-1 antibodies with high affinity for Clq, the first subunit of the complement cascade, and a single injection of such antibodies into prospective irradiated marrow recipients. Monoclonal mouse IgM and rat IgG 2c antibodies of high titers in complement-dependent test systems but with low affinity for Clq caused little immunosuppression. Monoclonal rat IgG2b or mouse IgG2a anti-Thy-1 antibodies with high affinity for Clq prevented acute and chronic mortality of graft-v-host disease (GVHD), however, when injected in irradiated CBA or AKR mice prior to C57BL/6 spleen and/or bone marrow cell transfusion. This treatment simultaneously suppressed residual host-v-graft reactivity of the irradiated mice, so that permanent hematopoietic engraftment ensued even at 5 or 6 Gy. Full chimerism and specific tolerance were obtained. Primary immune response to SRBC was clearly depressed in the chimeras; secondary immune response was not. Clearance of T cell antibody activity (greater than 6 days), timing, and dose of injected antibody, as well as other modalities of the conditioning treatment that may have contributed to the remarkable immunosuppression, are discussed

IgE and IgG cross-reactivity among Lol p I and Lol p II/III. Identification of the C-termini of Lol p I, II, and III as cross-reactive structures.

Science.gov (United States)

van Ree, R; van Leeuwen, W A; van den Berg, M; Weller, H H; Aalberse, R C

1994-04-01

In this study, the homologous C-termini of Lol p I, Lol p II, and Lol p III were shown to contain cross-reactive B-cell epitopes. This was demonstrated by inhibition studies with purified Lol p I, II, and III and synthetic peptides of their C-termini. It was ruled out that the observed cross-reactivity was caused by cross-contamination of the purified allergens. Both human IgE and IgG bound to the C-terminus of Lol p I. These antibodies were cross-reactive with Lol p II and, more specifically, with its C-terminus. Within a small panel of allergic patients, no cross-reactivity with Lol p III was found. A hyperimmune polyclonal rabbit antiserum against Lol p I also recognized the Lol p I C-terminus. As for human antibodies, cross-reactivity with Lol p II and its C-terminus was demonstrated. Cross-reactivity with Lol p III was demonstrated with C-terminal peptides, but not with native Lol p III. A polyclonal rabbit antiserum against Lol p II bound to the C-terminal peptides of both Lol p II and III. This binding was inhibited with Lol p I, confirming that cross-reactive structures exist not only on the C-termini of Lol p II and Lol p I, but also of Lol p III and Lol p I. The existence of cross-reactivity between Lol p I and Lol p II and III possibly contributes to the frequently observed cosensitization for these allergens in grass-pollen-allergic patients.

Transferability of antibody pairs from ELISA to fiber optic surface plasmon resonance for infliximab detection

Science.gov (United States)

Van Stappen, Thomas; Lu, Jiadi; Bloemen, Maarten; Geukens, Nick; Spasic, Dragana; Delport, Filip; Verbiest, Thierry; Lammertyn, Jeroen; Gils, Ann

2015-03-01

Tumor necrosis factor (TNF)-alpha is a pleiotropic cytokine up-regulated in inflammatory bowel disease, rheumatoid arthritis and psoriasis. The introduction of anti-TNF drugs such as infliximab has revolutionized the treatment of these diseases. Recently, therapeutic drug monitoring (TDM) of infliximab has been introduced in clinical decision making to increase cost-efficiency. Nowadays, TDM is performed using radio-immunoassays, homogeneous mobility shift assays or ELISA. Unfortunately, these assays do not allow for in situ treatment optimization, because of the required sample transportation to centralized laboratories and the subsequent assay execution time. In this perspective, we evaluated the potential of fiber optic-surface plasmon resonance (FO-SPR). To achieve this goal, a panel of 55 monoclonal anti-infliximab antibodies (MA-IFX) was developed and characterized in-house, leading to the identification of nine different clusters. Based on this high diversity, 22 antibody pairs were selected and tested for their reactivity towards IFX, using one MA-IFX as capture and one MA-IFX for detection, in a sandwich type ELISA and FO-SPR. This study showed that the reactivity towards IFX of each antibody pair in ELISA is highly similar to its reactivity on FO-SPR, indicating that antibody pairs are easily transferable between both platforms. Given the fact that FO-SPR shows the potential for miniaturization and fast assay time, it can be considered a highly promising platform for on-site infliximab monitoring.

Antibodies to Lactobacilli and Bifidobacteria in young children with different propensity to develop islet autoimmunity.

Science.gov (United States)

Talja, Ija; Kubo, Anna-Liisa; Veijola, Riitta; Knip, Mikael; Simell, Olli; Ilonen, Jorma; Vähä-Mäkilä, Mari; Sepp, Epp; Mikelsaar, Marika; Utt, Meeme; Uibo, Raivo

2014-01-01

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

A human PrM antibody that recognizes a novel cryptic epitope on dengue E glycoprotein.

Directory of Open Access Journals (Sweden)

Annie Hoi Yi Chan

Full Text Available Dengue virus (DENV is a major mosquito-borne pathogen infecting up to 100 million people each year; so far no effective treatment or vaccines are available. Recently, highly cross-reactive and infection-enhancing pre-membrane (prM-specific antibodies were found to dominate the anti-DENV immune response in humans, raising concern over vaccine candidates that contain native dengue prM sequences. In this study, we have isolated a broadly cross-reactive prM-specific antibody, D29, during a screen with a non-immunized human Fab-phage library against the four serotypes of DENV. The antibody is capable of restoring the infectivity of virtually non-infectious immature DENV (imDENV in FcγR-bearing K562 cells. Remarkably, D29 also cross-reacted with a cryptic epitope on the envelope (E protein located to the DI/DII junction as evidenced by site-directed mutagenesis. This cryptic epitope, while inaccessible to antibody binding in a native virus particle, may become exposed if E is not properly folded. These findings suggest that generation of anti-prM antibodies that enhance DENV infection may not be completely avoided even with immunization strategies employing E protein alone or subunits of E proteins.

Generation and Characterization of Anti-CD34 Monoclonal Antibodies that React with Hematopoietic Stem Cells

Science.gov (United States)

Aghebati Maleki, Leili; Majidi, Jafar; Baradaran, Behzad; Movassaghpour, Aliakbar; Abdolalizadeh, Jalal

2014-01-01

CD34 is a type I membrane protein with a molecular mass of approximately 110 kDa. This antigen is associated with human hematopoietic progenitor cells and is a differentiation stage-specific leukocyte antigen. In this study we have generated and characterized monoclonal antibodies (mAbs) directed against a CD34 marker. Mice were immunized with two keyhole lympet hemocyanin (KLH)-conjugated CD34 peptides. Fused cells were grown in hypoxanthine, aminopterine and thymidine (HAT) selective medium and cloned by the limiting dilution (L.D) method. Several monoclones were isolated by three rounds of limited dilutions. From these, we chose stable clones that presented sustained antibody production for subsequent characterization. Antibodies were tested for their reactivity and specificity to recognize the CD34 peptides and further screened by enzyme-linked immunosorbent assay (ELISA) and Western blotting analyses. One of the mAbs (3D5) was strongly reactive against the CD34 peptide and with native CD34 from human umbilical cord blood cells (UCB) in ELISA and Western blotting analyses. The results have shown that this antibody is highly specific and functional in biomedical applications such as ELISA and Western blot assays. This monoclonal antibodies (mAb) can be a useful tool for isolation and purification of human hematopoietic stem cells (HSCs). PMID:24611141

Antibody responses of swine following infection with Mycoplasma hyopneumoniae, M. hyorhinis, M. hyosynoviae and M. flocculare.

Science.gov (United States)

Gomes Neto, João Carlos; Strait, Erin L; Raymond, Matthew; Ramirez, Alejandro; Minion, F Chris

2014-11-07

Several mycoplasma species possessing a range of virulence have been described in swine. The most commonly described are Mycoplasma hyopneumoniae, Mycoplasma hyorhinis, Mycoplasma hyosynoviae, and Mycoplasma flocculare. They are ubiquitious in many pig producing areas of the world, and except for M. hyopneumoniae, commercial antibody-based assays are lacking for most of these. Antibody cross-reactivity among these four mycoplasma species is not well characterized. Recently, the use of pen-based oral fluids for herd surveillance is of increasing interest. Thus, this study sought to measure pig antibody responses and the level of cross-reactivity in serum and pen-based oral fluids after challenge with four species of swine mycoplasmas. Four groups of four mycoplasma-free growing pigs were separately inoculated with the different mycoplasma species. Pen-based oral fluids and serum samples were collected weekly until necropsy. Species-specific Tween 20 ELISAs were used to measure antibody responses along with four other commercial M. hyopneumoniae ELISAs. Animals from all groups seroconverted to the challenge species of mycoplasma and no evidence of cross-contamination was observed. A delayed antibody response was seen with all but M. hyorhinis-infected pigs. Cross-reactive IgG responses were detected in M. hyopneumoniae- and M. flocculare-infected animals by the M. hyorhinis Tween 20 ELISA, while sera from M. hyosynoviae and M. flocculare-infected pigs were positive in one commercial assay. In pen-based oral fluids, specific anti-M. hyopneumoniae IgA responses were detected earlier after infection than serum IgG responses. In summary, while some antibody-based assays may have the potential for false positives, evidence of this was observed in the current study. Copyright © 2014 Elsevier B.V. All rights reserved.

Structural Determination of the Broadly Reactive Anti-IGHV1-69 Anti-idiotypic Antibody G6 and Its Idiotope.

Science.gov (United States)

Avnir, Yuval; Prachanronarong, Kristina L; Zhang, Zhen; Hou, Shurong; Peterson, Eric C; Sui, Jianhua; Zayed, Hatem; Kurella, Vinodh B; McGuire, Andrew T; Stamatatos, Leonidas; Hilbert, Brendan J; Bohn, Markus-Frederik; Kowalik, Timothy F; Jensen, Jeffrey D; Finberg, Robert W; Wang, Jennifer P; Goodall, Margaret; Jefferis, Roy; Zhu, Quan; Kurt Yilmaz, Nese; Schiffer, Celia A; Marasco, Wayne A

2017-12-12

The heavy chain IGHV1-69 germline gene exhibits a high level of polymorphism and shows biased use in protective antibody (Ab) responses to infections and vaccines. It is also highly expressed in several B cell malignancies and autoimmune diseases. G6 is an anti-idiotypic monoclonal Ab that selectively binds to IGHV1-69 heavy chain germline gene 51p1 alleles that have been implicated in these Ab responses and disease processes. Here, we determine the co-crystal structure of humanized G6 (hG6.3) in complex with anti-influenza hemagglutinin stem-directed broadly neutralizing Ab D80. The core of the hG6.3 idiotope is a continuous string of CDR-H2 residues starting with M53 and ending with N58. G6 binding studies demonstrate the remarkable breadth of binding to 51p1 IGHV1-69 Abs with diverse CDR-H3, light chain, and antigen binding specificities. These studies detail the broad expression of the G6 cross-reactive idiotype (CRI) that further define its potential role in precision medicine. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Structural Determination of the Broadly Reactive Anti-IGHV1-69 Anti-idiotypic Antibody G6 and Its Idiotope

Directory of Open Access Journals (Sweden)

Yuval Avnir

2017-12-01

Full Text Available The heavy chain IGHV1-69 germline gene exhibits a high level of polymorphism and shows biased use in protective antibody (Ab responses to infections and vaccines. It is also highly expressed in several B cell malignancies and autoimmune diseases. G6 is an anti-idiotypic monoclonal Ab that selectively binds to IGHV1-69 heavy chain germline gene 51p1 alleles that have been implicated in these Ab responses and disease processes. Here, we determine the co-crystal structure of humanized G6 (hG6.3 in complex with anti-influenza hemagglutinin stem-directed broadly neutralizing Ab D80. The core of the hG6.3 idiotope is a continuous string of CDR-H2 residues starting with M53 and ending with N58. G6 binding studies demonstrate the remarkable breadth of binding to 51p1 IGHV1-69 Abs with diverse CDR-H3, light chain, and antigen binding specificities. These studies detail the broad expression of the G6 cross-reactive idiotype (CRI that further define its potential role in precision medicine.

Theoretical Calculation and Experimental Verification Demonstrated the Impossibility of Finding Haptens Identifying Triphenylmethane Dyes and Their Leuco Metabolites Simultaneously

Directory of Open Access Journals (Sweden)

De-Xin Kong

2018-03-01

Full Text Available Detection of triphenylmethane dyes (TDs, especially the widely used malachite green (MG and crystal violet (CV, plays an important role in safety control of aquatic products. There are two chromatic forms of TDs: oxidized or reduced. Usually, only one form can be detected by reported ELISA antibodies. In this article, molecular shape superimposing and quantum mechanics calculation were employed to elucidate the differences between MG, CV, and their reduced chromatic forms (leucomalachite green, LMG and leucocrystal violet, LCV. A potential hapten was rationally designed and synthesized. Polyclonal antibodies were raised through immunizing New Zealand white rabbits and BALB/C mice. We tested the cross-reactivity ratios between the hapten and TDs. The cross-reactivity ratios were correlated with the difference in surface electrostatic potential. The determination coefficients (r2 of the correlations are 0.901 and 0.813 for the rabbit and mouse antibody, respectively. According to this linear model, the significant difference in the atomic charge seemed to make it impossible to find a hapten that can produce antibodies with good cross-reactivities with both reduced and oxidized TDs.

A novel merozoite surface antigen of Plasmodium falciparum (MSP-3 identified by cellular-antibody cooperative mechanism antigenicity and biological activity of antibodies

Directory of Open Access Journals (Sweden)

Claude Oeuvray

1994-01-01

Full Text Available We report the identification of a 48kDa antigen targeted by antibodies which inhibit Plasmodium falciparum in vitro growth by cooperation with blood monocytes in an ADCI assay correlated to the naturally acquired protection. This protein is located on the surface of the merozoite stage of P. falciparum, and is detectable in all isolates tested. Epidemiological studies demonstrated that peptides derived from the amino acid sequence of MSP-3 contain potent B and T-cell epitopes recognized by a majority of individuals living in endemic areas. Moreover human antibodies either purified on the recombinant protein, or on the synthetic peptide MSP-3b, as well as antibodies raised in mice, were all found to promote parasite killing mediated by monocytes.

Seroprevalence of hepatitis C antibody in Peru.

Science.gov (United States)

Hyams, K C; Phillips, I A; Moran, A Y; Tejada, A; Wignall, F S; Escamilla, J

1992-06-01

The prevalence in Peru of antibody to hepatitis C virus (anti-HCV) was determined in a survey of populations living in the northern jungle region and in groups at high risk of parenterally and sexually transmitted diseases. All sera were initially screened for anti-HCV using commercial first and second generation ELISAs; repeatedly reactive sera were further verified with a second generation immunoblot assay. Serum samples were also tested by ELISA for HBsAg, anti-HBs, and anti-HBc. None of 2,111 sera obtained in the survey of jungle residents was positive for anti-HCV by immunoblot assay. Twelve of 16 HIV-1 antibody positive hemophiliacs, one of 103 HIV-1 antibody positive homosexuals, and three of 602 HIV-1 negative registered female prostitutes were positive for anti-HCV. A high prevalence of total markers of hepatitis B infection was found in all subjects, especially in older subjects and groups at high risk of parenterally and sexually transmitted diseases. The findings of this study indicate that seropositivity for hepatitis C virus antibody is uncommon in Peru except in high risk groups and suggest that the epidemiology of hepatitis C differs substantially from hepatitis B.

Analysis of Luminex-based algorithms to define unacceptable HLA antibodies in CDC-crossmatch negative kidney transplant recipients.

Science.gov (United States)

Zecher, Daniel; Bach, Christian; Preiss, Adrian; Staudner, Christoph; Utpatel, Kirsten; Evert, Matthias; Jung, Bettina; Bergler, Tobias; Böger, Carsten A; Spriewald, Bernd M; Banas, Bernhard

2018-02-20

HLA-specific antibodies detected by solid phase assays are increasingly used to define unacceptable HLA antigen mismatches (UAM) prior to renal transplantation. The accuracy of this approach is unclear. Day of transplant sera from 211 CDC-crossmatch-negative patients were retrospectively analyzed for donor-specific anti-HLA antibodies (DSA) using Luminex technology. HLA were defined as UAM if DSA had mean fluorescence intensity above (I) 3000 (patients retransplanted and those with DSA against HLA class I and II) or 5000 (all other patients), (II) 5000 for HLA A, B and DR and 10,000 for HLA DQ or (III) 10,000 (all HLA). We then studied the accuracy of these algorithms to identify patients with antibody-mediated rejection (AMR) and graft loss. UAM were also determined in 256 transplant candidates and virtual panel-reactive antibody (vPRA) levels calculated. At transplantation, 67/211 patients had DSA. Of these, 31 (algorithm I), 24 (II) and 17 (III) had UAM. 9 (I and II) and 8 (III) of 11 early AMR episodes and 7 (I), 6 (II) and 5 (III) of 9 graft losses occurred in UAM-positive patients during 4.9 years of follow-up. Algorithms (I) and (II) identified patients with persistently lower GFR even in the absence of overt AMR. 23-33% of waiting list patients had UAM with median vPRA of 69.2-79.1%. Algorithms (I) and (II) had comparable efficacy but were superior to (III) in identifying at-risk patients at an acceptable false positive rate. However, Luminex-defined UAM significantly restrict the donor pool of affected patients, which might prolong waiting time.

Monoclonal antibodies specific to sailfish serum albumin: development of an assay for the identification of fish species in the field.

Science.gov (United States)

Rossi, E A; Shepard, S R; Poyer, J C; Hartmann, J X

1992-06-01

Balb/c mice were immunized with albumin purified from sailfish (Istiophorus albicans) serum. Hybridomas were produced and screened by ELISA for reactivity with the purified albumins of sailfish, blue marlin (Makaira nigricans) and white marlin (Tetrapturus albidus). Monoclonal antibodies (MAbs) from 16 different clones exhibited activity against sailfish albumin. Thirteen of the MAbs showed cross-reactivity with the marlin species. Three MAbs exhibited distinct specificity for sailfish albumin. One of these species specific MAbs (M2D1) was conjugated to horseradish peroxidase (HRP) in order to construct an ELISA for identification of sailfish from serum. The ELISA for sailfish correctly identified eight sailfish from 26 billfish serum samples. The MAb-peroxidase conjugate was highly specific toward sailfish in that no reaction against heterologous species was detected.

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

Science.gov (United States)

Frick, O L; Brooks, D L

1983-03-01

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

Improvements in or relating to antibodies active against human hemoglobin Asub(1C)

International Nuclear Information System (INIS)

Javid, J.; Cerami, A.; Koenig, R.J.; Pettis, P.K.

1980-01-01

A method is described for preparing an antibody against human hemoglobin Asub(1c) which is substantially free of cross-reactivity against the human hemoglobins A 0 , Asub(1a) and Asub(1b). The antibodies are collected from cats, goats or sheep following injections of purified hemoglobin Asub(1c) antigen since these animals do not naturally produce hemoglobin Asub(1c). A radioimmunoassay method is also described whereby these antibodies are used to determine the quantity of hemoglobin Asub(1c) in blood samples. This is a useful technique in the diagnosis of diabetes mellitus. (U.K.)

Multiplex flow cytometry barcoding and antibody arrays identify surface antigen profiles of primary and metastatic colon cancer cell lines.

Directory of Open Access Journals (Sweden)

Kumar Sukhdeo

Full Text Available Colon cancer is a deadly disease affecting millions of people worldwide. Current treatment challenges include management of disease burden as well as improvements in detection and targeting of tumor cells. To identify disease state-specific surface antigen signatures, we combined fluorescent cell barcoding with high-throughput flow cytometric profiling of primary and metastatic colon cancer lines (SW480, SW620, and HCT116. Our multiplexed technique offers improvements over conventional methods by permitting the simultaneous and rapid screening of cancer cells with reduced effort and cost. The method uses a protein-level analysis with commercially available antibodies on live cells with intact epitopes to detect potential tumor-specific targets that can be further investigated for their clinical utility. Multiplexed antibody arrays can easily be applied to other tumor types or pathologies for discovery-based approaches to target identification.

Frequency and significance of antibodies to liver/kidney microsome type 1 in adults with chronic active hepatitis.

Science.gov (United States)

Czaja, A J; Manns, M P; Homburger, H A

1992-10-01

To assess the frequency of antibodies to liver/kidney microsome type 1 (anti-LKM1) in patients with chronic active hepatitis, 131 such patients were tested by an indirect immunofluorescence assay. Of 62 patients with type 1 autoimmune hepatitis, none were seropositive. In contrast, 3 of 11 patients with autoimmune hepatitis and antimitochondrial antibodies (27%) were seropositive for anti-LKM1. Each had responded to corticosteroid therapy, and retesting of sera confirmed that each had been misclassified as antimitochondrial antibody positive. None of the patients with chronic active hepatitis B (14 patients) or C (24 patients) had anti-LKM1. Similarly, none of the 20 patients with cryptogenic disease had these antibodies. It is concluded that anti-LKM1 is specific for type 2 autoimmune hepatitis and is infrequent in adult patients seen at a referral center in the United States for chronic active hepatitis. Anti-LKM1 reactivity may be misinterpreted as antimitochondrial antibody reactivity by indirect immunofluorescence. Chronic hepatitis B and C virus infections are not important stimuli for the production of anti-LKM1, and testing for anti-LKM 1 is unlikely to clarify the nature of cryptogenic disease.

Anti-liver-kidney microsome antibody type 1 recognizes human cytochrome P450 db1.

Science.gov (United States)

Gueguen, M; Yamamoto, A M; Bernard, O; Alvarez, F

1989-03-15

Anti-liver-kidney microsome antibody type 1 (LKM1), present in the sera of a group of children with autoimmune hepatitis, was recently shown to recognize a 50 kDa protein identified as rat liver cytochromes P450 db1 and db2. High homology between these two members of the rat P450 IID subfamily and human P450 db1 suggested that anti-LKM1 antibody is directed against this human protein. To test this hypothesis, a human liver cDNA expression library in phage lambda GT-11 was screened using rat P450 db1 cDNA as a probe. Two human cDNA clones were found to be identical to human P450 db1 by restriction mapping. Immunoblot analysis using as antigen, the purified fusion protein from one of the human cDNA clones showed that only anti-LKM1 with anti-50 kDa reactivity recognized the fusion protein. This fusion protein was further used to develop an ELISA test that was shown to be specific for sera of children with this disease. These results: 1) identify the human liver antigen recognized by anti-LKM1 auto-antibodies as cytochrome P450 db1, 2) allow to speculate that mutation on the human P450 db1 gene could alter its expression in the hepatocyte and make it auto-antigenic, 3) provide a simple and specific diagnostic test for this disease.

Monoclonal antibodies from rats immunized with fragment D of human fibrinogen

International Nuclear Information System (INIS)

Kennel, S.J.; Chen, J.P.; Lankford, P.K.; Foote, L.J.

1981-01-01

Fischer rats were immunized with fragment D (Fg-D) of human fibrinogen (Fg) to obtain antibody specific for neoantigens unique to this molecule. Absorption of serum with whole Fg indicated that some of the antibody produced reacted preferentially with Fg-D. Hybridoma cultures were prepared by fusion of immune rat spleen cells with mouse myeloma P3-X63-Ag8. Monoclonal antibodies obtained from these cultures fell into two classes: (a) Those reacting equally well with Fg and Fg-D. (b) Those reacting preferentially but not absolutely wth Fg-D. Antibody from hybridoma 104-14, a member of the first group had an affinity for Fg-D of 1.5 x 10 9 M -1 while antibodies from 106-59 and 106-71 (group 2) demonstrated much lower affinities of 1.0 x 10 7 and 4.7 x 10 6 M -1 , respectively. The cross reactivity of antibodies in the second group indicated that they react with protein conformations that are altered during production of Fg-D from Fg

Iodoacetyl-functionalized pullulan: A supplemental enhancer for single-domain antibody-polyclonal antibody sandwich enzyme-linked immunosorbent assay for detection of survivin.

Science.gov (United States)

Matsushita, Takahiko; Arai, Hidenao; Koyama, Tetsuo; Hatano, Ken; Nemoto, Naoto; Matsuoka, Koji

2017-11-01

Survivin, an inhibitor of the apoptosis protein family, is a potent tumor marker for diagnosis and prognosis. The enzyme-linked immunosorbent assay (ELISA) is one of the methods that has been used for detection of survivin. However, ELISA has several disadvantages caused by the use of conventional antibodies, and we have therefore been trying to develop a novel ELISA system using camelid single-domain antibodies (VHHs) as advantageous replacements. Here we report a supplemental approach to improve the VHH-polyclonal antibody sandwich ELISA for survivin detection. Iodoacetyl-functionalized pullulan was synthesized, and its thiol reactivity was characterized by a model reaction with l-cysteine. The thiophilic pullulan was applied to an immunoassay asan additive upon coating of standard assay plates with an anti-survivin VHH fusion protein with C-terminal cysteine. The results showed that the mole ratio of the additive to VHH had a significant effect on the consequent response. Mole ratios of 0.07, 0.7, and 7 led to 90% lower, 15% higher, and 69% lower responses, respectively, than the response of a positive control in which no additive was used. The background levels observed in any additive conditions were as low as that of a negative control lacking both VHH and the additive. These results indicate the applicability of the thiol-reactive pullulan as a response enhancer to VHH-based ELISA. Copyright © 2017 Elsevier Ltd. All rights reserved.

Screening and identification of T helper 1 and linear immunodominant antibody-binding epitopes in the spike 2 domain and the nucleocapsid protein of feline infectious peritonitis virus.

Science.gov (United States)

Satoh, Ryoichi; Furukawa, Tomoko; Kotake, Masako; Takano, Tomomi; Motokawa, Kenji; Gemma, Tsuyoshi; Watanabe, Rie; Arai, Setsuo; Hohdatsu, Tsutomu

2011-02-17

The antibody-dependent enhancement (ADE) of feline infectious peritonitis virus (FIPV) infection has been recognized in experimentally infected cats, and cellular immunity is considered to play an important role in preventing the onset of feline infectious peritonitis (FIP). In the present study, we synthesized eighty-one kinds of peptides derived from the spike (S)2 domain of type I FIPV KU-2 strain, the S2 domain of type II FIPV 79-1146 strain, and the nucleocapcid (N) protein of FIPV KU-2 strain. To detect the T helper (Th)1 epitope, peripheral blood mononuclear cells (PBMCs) obtained from FIPV-infected cats were cultured with each peptide, and Th1-type immune responses were measured using feline interferon (fIFN)-γ production as an index. To detect the linear immunodominant antibody-binding epitope, we investigated the reactivity of plasma collected from FIPV-infected cats against each peptide by ELISA. Four and 2 peptides containing Th1 epitopes were identified in the heptad repeat (HR)1 and inter-helical (IH) regions of the S2 domain of type I FIPV, respectively, and these were located on the N-terminal side of the regions. In the S2 domain of type II FIPV, 2, 3, and 2 peptides containing Th1 epitopes were identified in the HR1, IH, and HR2 regions, respectively, and these were mainly located on the C-terminal side of the regions. In the S2 domain of type I FIPV, 3 and 7 peptides containing linear immunodominant antibody-binding epitopes were identified in the IH and HR2 regions, respectively. In the S2 domain of type II FIPV, 4 peptides containing linear immunodominant antibody-binding epitopes were identified in the HR2 region. The Th1 epitopes in the S2 domain of type I and II FIPV were located in different regions, but the linear immunodominant antibody-binding epitopes were mostly located in the HR2 region. Eight peptides containing Th1 epitopes were identified in N protein, and 3 peptides derived from residues 81 to 100 and 137 to 164 showed strong

Investigation of a panel of monoclonal antibodies and polyclonal sera against anthrax toxins resulted in identification of an anti-lethal factor antibody with disease-enhancing characteristics.

Science.gov (United States)

Kulshreshtha, Parul; Tiwari, Ashutosh; Priyanka; Joon, Shikha; Sinha, Subrata; Bhatnagar, Rakesh

2015-12-01

Hybridomas were created using spleen of mice that were actively immunized with rLFn (recombinant N-terminal domain of lethal factor). Later on, separate group of mice were immunized with rLFn to obtain a polyclonal control for passive immunization studies of monoclonal antibodies. This led to the identification of one cohort of rLFn-immnized mice that harboured disease-enhancing polyclonal antibodies. At the same time, the monoclonal antibodies secreted by all the hybridomas were being tested. Two hybridomas secreted monoclonal antibodies (H10 and H8) that were cross-reactive with EF (edema factor) and LF (lethal factor), while the other two hybridomas secreted LF-specific antibodies (H7 and H11). Single chain variable fragment (LETscFv) was derived from H10 hybridoma. H11 was found to have disease-enhancing property. Combination of H11 with protective monoclonal antibodies (H8 and H10) reduced its disease enhancing nature. This in vitro abrogation of disease-enhancement provides the proof of concept that in polyclonal sera the disease enhancing character of a fraction of antibodies is overshadowed by the protective nature of the rest of the antibodies generated on active immunization. Copyright © 2015. Published by Elsevier Ltd.

Human autoantibodies against Clq: lack of cross reactivity with the collectins mannan-binding protein, lung surfactant protein A and bovine conglutinin.

Science.gov (United States)

Mårtensson, U; Thiel, S; Jensenius, J C; Sjöholm, A G

1996-03-01

The collectins, a group of humoral C-type lectins, have globular and collagen-like regions and share structural features with the complement protein C1q. The question was asked if autoantibodies to the collagen-like region of C1q (anti-C1qCLR) might cross-react with collectins, such as mannan-binding protein (MBP), lung surfactant protein A (SP-A) and bovine conglutinin (BK). Anti-C1qCLR antibodies of the systemic lupus erythematosus (SLE) type and anti-C1qCLR antibodies of the hypocomplementemic urticarial vasculitis syndrome (HUVS) type were investigated. Cross-absorption and elution experiments combined with antibody detection by enzyme-linked immunosorbent assay (ELISA) and immunoblot analysis gave no evidence of cross-reactive anti-C1qCLR antibodies. However, one serum with HUVS type anti-C1qCLR antibodies contained anti-MBP antibodies that were cross-reactive with SP-A. Judging from results of ELISA inhibition experiments and immunoblot analysis, four SLE sera contained antibodies to native BK, while two sera with HUVS type anti-C1qCLR antibodies contained antibodies to epitopes of denatured BK. This might imply that autoimmunity to collagen-like structures is not restricted to C1qCLR in HUVS and HUVS/SLE overlap syndromes.

Detection of Antibodies against Paracoccidioides brasiliensis Melanin in In Vitro and In Vivo Studies during Infection ▿

Science.gov (United States)

Urán, Martha E.; Nosanchuk, Joshua D.; Restrepo, Angela; Hamilton, Andrew J.; Gómez, Beatriz L.; Cano, Luz E.

2011-01-01

Several cell wall constituents, including melanins or melanin-like compounds, have been implicated in the pathogenesis of a wide variety of microbial diseases caused by diverse species of pathogenic bacteria, fungi, and helminthes. Among these microorganisms, the dimorphic fungal pathogen Paracoccidioides brasiliensis produces melanin in its conidial and yeast forms. In the present study, melanin particles from P. brasiliensis were injected into BALB/c mice in order to produce monoclonal antibodies (MAbs). We identified five immunoglobulin G1 (IgG1) κ-chain and four IgM melanin-binding MAbs. The five IgG1 κ-chain isotypes are the first melanin-binding IgG MAbs ever reported. The nine MAbs labeled P. brasiliensis conidia and yeast cells both in vitro and in pulmonary tissues. The MAbs cross-reacted with melanin-like purified particles from other fungi and also with commercial melanins, such as synthetic and Sepia officinalis melanin. Melanization during paracoccidioidomycosis (PCM) was also further supported by the detection of IgG antibodies reactive to melanin from P. brasiliensis conidia and yeast in sera and bronchoalveolar lavage fluids from P. brasiliensis-infected mice, as well as in sera from human patients with PCM. Serum specimens from patients with other mycoses were also tested for melanin-binding antibodies by enzyme-linked immunosorbent assay, and cross-reactivities were detected for melanin particles from different fungal sources. These results suggest that melanin from P. brasiliensis is an immunologically active fungal structure that activates a strong IgG humoral response in humans and mice. PMID:21813659

Characterization of antibodies to dihydrothymine, a radiolysis product of DNA

International Nuclear Information System (INIS)

Hubbard, K.; Ide, H.; Erlanger, B.F.; Wallace, S.S.

1989-01-01

Antibodies to dihydrothymine were elicited by immunizing rabbits with dihydrothymidine monophosphate conjugated by carbodiimide to BSA. By use of an ELISA assay, the antibodies produced were found to be specific for dihydrothymine. Hapten inhibition studies showed that dihydrothymidine monophosphate was 3 orders of magnitude more effective as an inhibitor than thymidine monophosphate and 4 orders of magnitude more effective than thymidine glycol monophosphate. With DNA containing dihydrothymine, antibody reactivity was observed at 20 fmol of dihydrothymine, which is approximately 0.1 dihydrothymine per 10,000 bases. Thus, the assay is very sensitive. The antibody reacted with denatured DNA containing dihydrothymine but not with native DNA containing this lesion. The antibody was used for measurement of in vivo incorporation of dihydrothymidine in wild-type Escherichia coli or mutants defective in their ability to remove dihydrothymine from DNA or in the de novo synthesis of thymidylate. Lastly, antibodies to dihydrothymine were use to quantitate the formation of dihydrothymine in DNA X-irradiated under N2. Production of dihydrothymine in irradiated DNA correlated with the level of reducing species produced by X-rays, and dihydrothymine was produced preferentially in irradiated single-stranded or denatured DNA as compared to irradiated duplex DNA

Antibody Maturation in Trypanosoma cruzi-Infected Rats

Science.gov (United States)

Marcipar, Iván S.; Risso, Marikena G.; Silber, Ariel M.; Revelli, Silvia; Marcipar, Alberto J.

2001-01-01

The study of antibody avidity changes during infection has improved the understanding of the pathologic processes involved in several infectious diseases. In some infections, like toxoplasmosis, this information is being used for diagnostic purposes. Results of the evolution of antibody avidity for different specific antigens in Trypanosome cruzi-infected rats are presented. A Western blotting technique, combined with avidity analysis to identify antigens that elicit high-avidity antibodies, is suggested. In this system, antibodies showed high avidity values only during the chronic phase of infection and only in relation to antibodies against 21-, 33-, 41-, 42-, 56-, 58-, 66-, and 72-kDa antigens. Finally, a 97-kDa T. cruzi antigen, which was recognized by high-avidity antibodies and occurred in noninfected rats, was identified. These results allow us to evaluate the different antigens in chagasic infection. Our results show that with the correct choice of antigen it is possible to detect differences in maturation of antibodies and to discriminate, in an experimental model, between recent (acute) and chronic infections. PMID:11427430

Antibody Desensitization Therapy in Highly Sensitized Lung Transplant Candidates

Science.gov (United States)

Snyder, L. D.; Gray, A. L.; Reynolds, J. M.; Arepally, G. M.; Bedoya, A.; Hartwig, M. G.; Davis, R. D.; Lopes, K. E.; Wegner, W. E.; Chen, D. F.; Palmer, S. M.

2015-01-01

As HLAs antibody detection technology has evolved, there is now detailed HLA antibody information available on prospective transplant recipients. Determining single antigen antibody specificity allows for a calculated panel reactive antibodies (cPRA) value, providing an estimate of the effective donor pool. For broadly sensitized lung transplant candidates (cPRA ≥ 80%), our center adopted a pretransplant multimodal desensitization protocol in an effort to decrease the cPRA and expand the donor pool. This desensitization protocol included plasmapheresis, solumedrol, bortezomib and rituximab given in combination over 19 days followed by intravenous immunoglobulin. Eight of 18 candidates completed therapy with the primary reasons for early discontinuation being transplant (by avoiding unacceptable antigens) or thrombocytopenia. In a mixed-model analysis, there were no significant changes in PRA or cPRA changes over time with the protocol. A sub-analysis of the median fluorescence intensity (MFI) change indicated a small decline that was significant in antibodies with MFI 5000–10 000. Nine of 18 candidates subsequently had a transplant. Posttransplant survival in these nine recipients was comparable to other pretransplant-sensitized recipients who did not receive therapy. In summary, an aggressive multi-modal desensitization protocol does not significantly reduce pretransplant HLA antibodies in a broadly sensitized lung transplant candidate cohort. PMID:24666831

Development of a 'mouse and human cross-reactive' affinity-matured exosite inhibitory human antibody specific to TACE (ADAM17) for cancer immunotherapy.

Science.gov (United States)

Kwok, Hang Fai; Botkjaer, Kenneth A; Tape, Christopher J; Huang, Yanchao; McCafferty, John; Murphy, Gillian

2014-06-01

We previously showed that a human anti-TACE antibody, D1(A12), is a potent inhibitor of TNF-α converting enzyme (TACE) ectodomain proteolysis and has pharmacokinetic properties suitable for studies of the inhibition of TACE-dependent growth factor shedding in relation to possible therapeutic applications. However, the lack of murine TACE immunoreactivity limits pre-clinical in vivo studies to human xenograft models which are poor analogies to in situ pathology and are not considered clinically predictive. Here, to overcome these limitations, we set out to develop a 'mouse and human cross-reactive' specific anti-TACE antibody. We first re-investigated the originally selected anti-TACE ectodomain phage-display clones, and isolated a lead 'mouse-human cross-reactive' anti-TACE scFv, clone A9. We reformatted scFv-A9 into an IgG2 framework for comprehensive biochemical and cellular characterization and further demonstrated that A9 is an exosite TACE inhibitor. However, surface plasmon resonance analysis and quenched-fluorescent (QF) peptide assay indicated that IgG reformatting of A9 caused low binding affinity and an 80-fold reduction in TACE ectodomain inhibition, severely limiting its efficacy. To address this, we constructed second generation phage-display randomization libraries focused on the complementarity-determining region 3, and carried out affinity selections shuffling between human and mouse TACE ectodomain as antigen in addition to an off-rate selection to increase the chance of affinity improvement. The bespoke 'three-step' selections enabled a 100-fold affinity enhancement of A9 IgG, and also improved its IC50 in a QF peptide assay to 0.2 nM. In human and mouse cancer cell assays, matured A9 IgG showed significant cell-surface TACE inhibition as a monotherapy or combination therapy with chemotherapeutic agent. Collectively, these data suggest that we successfully developed an exosite inhibitor of TACE with sub-nanomolar affinity, which possesses both

Antibodies to Pseudogymnoascus destructans are not sufficient for protection against white-nose syndrome.

Science.gov (United States)

Johnson, Joseph S; Reeder, DeeAnn M; Lilley, Thomas M; Czirják, Gábor Á; Voigt, Christian C; McMichael, James W; Meierhofer, Melissa B; Seery, Christopher W; Lumadue, Shayne S; Altmann, Alexander J; Toro, Michael O; Field, Kenneth A

2015-06-01

White-nose syndrome (WNS) is a fungal disease caused by Pseudogymnoascus destructans (Pd) that affects bats during hibernation. Although millions of bats have died from WNS in North America, mass mortality has not been observed among European bats infected by the fungus, leading to the suggestion that bats in Europe are immune. We tested the hypothesis that an antibody-mediated immune response can provide protection against WNS by quantifying antibodies reactive to Pd in blood samples from seven species of free-ranging bats in North America and two free-ranging species in Europe. We also quantified antibodies in blood samples from little brown myotis (Myotis lucifugus) that were part of a captive colony that we injected with live Pd spores mixed with adjuvant, as well as individuals surviving a captive Pd infection trial. Seroprevalence of antibodies against Pd, as well as antibody titers, was greater among little brown myotis than among four other species of cave-hibernating bats in North America, including species with markedly lower WNS mortality rates. Among little brown myotis, the greatest titers occurred in populations occupying regions with longer histories of WNS, where bats lacked secondary symptoms of WNS. We detected antibodies cross-reactive with Pd among little brown myotis naïve to the fungus. We observed high titers among captive little brown myotis injected with Pd. We did not detect antibodies against Pd in Pd-infected European bats during winter, and titers during the active season were lower than among little brown myotis. These results show that antibody-mediated immunity cannot explain survival of European bats infected with Pd and that little brown myotis respond differently to Pd than species with higher WNS survival rates. Although it appears that some species of bats in North America may be developing resistance to WNS, an antibody-mediated immune response does not provide an explanation for these remnant populations.

Application of murine monoclonal antibodies to the serodiagnosis of tuberculosis

International Nuclear Information System (INIS)

Ivanyl, J.; Coates, A.R.M.; Krambovitis, E.

1982-01-01

The immune response during infectious diseases leads to a rise in antibody titre to the various different antigenic determinants of the causative organism. The response is further complicated by the fact that it is relatively unusual for one individual to respond to all antigenic components of an organism. Demonstration of the specific immune response of an infected host by serological tests is often hampered by the broad cross-reactivity between several bacterial antigens. The authors report on a serodiagnostic application of murine monoclonal antibodies (MAB), specific for a human pathogen, M. tuberculosis by a technique which is applicable in principle to the serodiagnosis of many other infectious diseases. The serum diagnostic test is based on the competitive inhibition by human sera of the binding of 125 I-labelled murine monoclonal antibodies to M. tuberculosis-coated polyvinyl plates. Five monoclonal antibodies binding to distinct antigenic determinants of the organism were used as structural probes which conferred their stringent combining site specificities to the polyclonal mixture of antibodies from patients' sera. When compared with healthy controls, increased titres of inhibitory antibodies were found in about 70% of patients with active tuberculosis. The diagnostic value of the individual monoclonal antibodies as well as the benefit from the use of multiple specificity probes has been qualified

Lack of antibodies to NMDAR or VGKC-complex in GAD and cardiolipin antibody-positive refractory epilepsy.

Science.gov (United States)

Liimatainen, Suvi; Peltola, Jukka; Hietaharju, Aki; Sabater, Lidia; Lang, Bethan

2014-03-01

Over the last few years autoantibodies against neuronal proteins have been identified in several forms of autoimmune encephalitis and epilepsy. NMDA receptor (NMDAR) and voltage gated potassium channel (VGKC) complex antibodies are mainly associated with limbic encephalitis (LE) whereas glutamic acid decarboxylase antibodies (GADA) and anticardiolipin (ACL) antibodies are more commonly detected in patients with chronic epilepsy. Clinical features vary between these antibodies suggesting the specificity of different neuronal antibodies in seizures. Serum samples of 14 GADA positive and 24 ACL positive patients with refractory epilepsy were analyzed for the presence of VGKC or NMDAR antibodies. No positive VGKC or NMDAR antibodies were found in these patients. The results confirm the different significance of these neuronal antibodies in seizure disorders. Different autoantibodies have different significance in seizures and probably have different pathophysiological mechanisms of actions. Copyright © 2014 Elsevier B.V. All rights reserved.

PERFORMANCE EVALUATION OF A PROTOTYPE ARCHITECT ANTIBODY ASSAY FOR BABESIA MICROTI.

Science.gov (United States)

Cheng, Kevin; Coller, Kelly E; Marohnic, Christopher C; Pfeiffer, Zachary A; Fino, James R; Elsing, Randee R; Bergsma, Janet; Marcinkus, Marilee A; Kar, Alak K; Gumbs, Orlando H; Otis, Kathy S; Fishpaugh, Jeffrey; Schultz, Phillip W; Pope, Mark R; Narvaez, Alfredo R; Wong, Susan J; Madison-Antenucci, Susan; Leary, Thomas P; Dawson, George J

2018-05-09

The tick-borne protozoan Babesia microti is responsible for more than 200 cases of transfusion-transmitted babesiosis (TTB) infection in the United States over the last 30 years. Measures to mitigate the risk of TTB include nucleic acid testing (NAT) and B. microti antibody testing. A fully automated prototype B. microti antibody test was developed on the ARCHITECT instrument. The specificity was determined to be 99.98% in volunteer blood donors (n=28,740) from areas considered as low endemic for B. microti The sensitivity of the prototype test was studied in experimentally-infected macaques; a total of 128 samples were detected compared to 125 with the indirect fluorescent antibody test (IFA), additionally, 83 (89.2%) of the PCR positive samples were detected compared to 81 (87.1%) using the IFA test. All PCR positive samples that tested negative in the prototype antibody test were pre-seroconversion period samples. Following seroconversion, periods of intermittent parasitemia occurred; 17 PCR negative samples drawn in-between PCR positive bleed dates, tested positive both by the prototype test (robust reactivity) and IFA (marginal reactivity) prior to the administration of therapeutic drugs, indicating that the PCR test failed to detect samples from persistently infected macaques. The prototype assay detected 56 of 58 (96.6%) human subjects diagnosed with clinical babesiosis by both PCR and IFA testing. Overall, the prototype anti-babesia assay provides a highly sensitive and specific test for the diagnosis of B. microti infection. While PCR is preferred for detection of window period parasitemia, antibody tests detect infected subjects during periods of low level parasitemia. Copyright © 2018 Cheng et al.

A murine monoclonal antibody based enzyme-linked immunosorbent assay for almond (Prunus dulcis L.) detection.

Science.gov (United States)

Su, Mengna; Venkatachalam, Mahesh; Liu, Changqi; Zhang, Ying; Roux, Kenneth H; Sathe, Shridhar K

2013-11-13

A sandwich enzyme-linked immunosorbent assay (ELISA) using anti-almond soluble protein rabbit polyclonal antibodies as capture antibodies and murine monoclonal antibody 4C10 as the detection antibodies was developed. The assay is specific and sensitive (3-200 ng almond protein/mL) for almond detection. The standardized assay is accurate (assay variability assay did not register any cross-reactivity with the tested food matrices, suggesting the assay to be almond amandin specific. The assay could detect the presence of declared almond in the tested matched commercial samples. Further, the assay reliably detected the presence of almonds in the laboratory prepared food samples spiked with almond flour.

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

Energy Technology Data Exchange (ETDEWEB)

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

2010-11-15

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

I-125 input into antibodies molecules specific to australian antigen

International Nuclear Information System (INIS)

Abdukayumov, A. M.; Chistyakov, P.G.; Garajshina, G. R.

1999-01-01

There are experimental data on I-125 input into antibodies molecules specific to superficial antigen of hepatitis B virus (australian antigen). Three ways of input are submitted: with the help of T chloramine usage, Bolton-Hunter Reagent and with the help of iodogen. There are also comparative characteristics of iodized products obtained: molar radioactivity, radiochemical frequency, immuno - reactivity. The report also discusses advantages and disadvantages of the used methods for inputting I-125 into antibodies to australian antigen in order to study the possibility of creating radio immunological test system for detecting superficial antigen of B hepatitis

Polyclonal and monoclonal antibodies in clinic.

Science.gov (United States)

Wootla, Bharath; Denic, Aleksandar; Rodriguez, Moses

2014-01-01

Immunoglobulins (Ig) or antibodies are heavy plasma proteins, with sugar chains added to amino-acid residues by N-linked glycosylation and occasionally by O-linked glycosylation. The versatility of antibodies is demonstrated by the various functions that they mediate such as neutralization, agglutination, fixation with activation of complement and activation of effector cells. Naturally occurring antibodies protect the organism against harmful pathogens, viruses and infections. In addition, almost any organic chemical induces antibody production of antibodies that would bind specifically to the chemical. These antibodies are often produced from multiple B cell clones and referred to as polyclonal antibodies. In recent years, scientists have exploited the highly evolved machinery of the immune system to produce structurally and functionally complex molecules such as antibodies from a single B clone, heralding the era of monoclonal antibodies. Most of the antibodies currently in the clinic, target components of the immune system, are not curative and seek to alleviate symptoms rather than cure disease. Our group used a novel strategy to identify reparative human monoclonal antibodies distinct from conventional antibodies. In this chapter, we discuss the therapeutic relevance of both polyclonal and monoclonal antibodies in clinic.

Profilin is a cross-reactive allergen in pollen and vegetable foods

NARCIS (Netherlands)

van Ree, R.; Voitenko, V.; van Leeuwen, W. A.; Aalberse, R. C.

1992-01-01

Sera with IgE antibodies against grass pollen often contain IgE against vegetable foods. We investigated the role of the ubiquitous protein profilin in this cross-reactivity. Profilin was purified from Lolium perenne grass pollen by means of affinity purification with Sepharose-coupled

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

Science.gov (United States)

2011-04-01

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

42 CFR 493.865 - Standard; Antibody identification.

Science.gov (United States)

2010-10-01

... 42 Public Health 5 2010-10-01 2010-10-01 false Standard; Antibody identification. 493.865 Section..., Or Any Combination of These Tests § 493.865 Standard; Antibody identification. (a) Failure to attain... proficiency testing event. (e) Failure to identify the same antibody in two consecutive or two out of three...

Monoclonal antibodies to human mammary tumor-associated antigens and their use for radiolocalization of xenografts in athymic mice

International Nuclear Information System (INIS)

Colcher, D.; Schlom, J.

1983-01-01

The authors have utilized membrane-enriched extracts of human metastatic mammary tumor cells as immunogens to generate and characterize monoclonal antibodies reactive with determinants that would be maintained on metastatic, as well as primary, human mammary carcinoma cells. Multiple assays using tumor cells extracts, tissue sections, and live cells in culture have been employed to reveal the diversity of the monoclonal antibodies generated. Then the utility of these antibodies for radiolocalization studies was examined. (Auth.)

Heterophilic interference in specimens yielding false-reactive results on the Abbott 4th generation ARCHITECT HIV Ag/Ab Combo assay.

Science.gov (United States)

Lavoie, S; Caswell, D; Gill, M J; Kadkhoda, K; Charlton, C L; Levett, P N; Hatchette, T; Garceau, R; Maregmen, J; Mazzulli, T; Needle, R; Kadivar, K; Kim, J

2018-04-12

False-reactivity in HIV-negative specimens has been detected in HIV fourth-generation antigen/antibody or 'combo' assays which are able to detect both anti-HIV-1/HIV-2 antibodies and HIV-1 antigen. We sought to characterize these specimens and determine the effect of heterophilic interference. Specimens previously testing as false-reactive on the Abbott ARCHITECT HIV Ag/Ab combo assay and re-tested on a different (Siemens ADVIA Centaur HIV Ag/Ab) assay. A subset of these specimens were also pre-treated with heterophilic blocking agents and re-tested on the Abbott assay. Here we report that 95% (252/264) of clinical specimens that were repeatedly reactive on the Abbott ARCHITECT HIV Ag/Ab combo assay (S/Co range, 0.94-678) were negative when re-tested on a different fourth generation HIV combo assay (Siemens ADVIA Centaur HIV Ag/Ab). All 264 samples were subsequently confirmed to be HIV negative. On a small subset (57) of specimens with available volume, pre-treatment with two different reagents (HBT; Heterophilic Blocking Tube, NABT; Non-Specific Blocking Tube) designed to block heterophilic antibody interference either eliminated (HBT) or reduced (NABT) the false reactivity when re-tested on the ARCHITECT HIV Ag/Ab combo assay. Our results suggest that the Abbott ARCHITECT HIV Ag/Ab combo assay can be prone to heterophilic antibody interference. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

Development and Characterization of Mouse Monoclonal Antibodies Reactive with Chicken CD83

Science.gov (United States)

This study was carried out to develop and characterize mouse monoclonal antibodies (mAbs) against chicken CD83 (chCD83), a membrane-bound glycoprotein belonging to the immunoglobulin superfamily that is primarily expressed on mature dendritic cells (DCs). A recombinant chCD83/IgG4 fusion protein con...

Tumor imaging with monoclonal antibodies

International Nuclear Information System (INIS)

Haisma, H.; Hilgers, J.

1987-01-01

Many monoclonal antibodies directed against tumor-associated antigens have been identified, but so far none of these are tumor specific. Polyclonal and monoclonal antibodies have been used for imaging of a wide variety of tumors with success. Radiolabeling of antibody is usually done with iodine isotopes of which 123 I is the best candidate for radioimmunodetection purposes. The labeling of antibodies through chelates makes it possible to use metal radioisotopes like 111 In, which is the best radioisotope for imaging with monoclonal antibodies due to its favorable half-life of 2.5 days. Usually imaging cannot be performed within 24 h after injection, but clearance of antibody can be increased by using F(ab) 2 of Fab. Another approach is to clear non-bound antibody by a second antibody, directed against the first. The detection limit of immunoimaging is about 2 cm, but will be improved by tomography or SPECT. There is still a high false positive and false negative rate, which makes it impossible to use radioimmunodetection as the only technique for diagnosis of tumors. In combination with other detection techniques, tumor imaging with monoclonal antibodies can improve diagnosis. 44 refs.; 3 tabs

Space Flight-Induced Reactivation of Latent Epstein-Barr Virus

Science.gov (United States)

Stowe, Raymond P.; Barrett, Alan D. T.; Pierson, Duane L.

2001-01-01

Reactivation of latent Epstein-Barr virus (EBV) may be an important threat to crew health during extended space missions. Decreased cellular immune function has been reported both during and after space flight. Preliminary studies have demonstrated increased EBV shedding in saliva as well as increased antibody titers to EBV lytic proteins. We hypothesize that the combined effects of microgravity along with associated physical and psychological stress will decrease EBV-specific T-cell immunity and reactivate latent EBV in infected B-lymphocytes. If increased virus production and clonal expansion of infected B-lymphocytes are detected, then pharmacological measures can be developed and instituted prior to onset of overt clinical disease. More importantly, we will begin to understand the basic mechanisms involved in stress-induced reactivation of EBV in circulating B-lymphocytes.

Experiments toward the development of a radioimmunoassay for the detection of serum antibodies for the respiratory syncytial virus

International Nuclear Information System (INIS)

Heizmann, W.R.

1982-01-01

In order to detect an infection by the respiratory syncytial virus (RSV) quickly and safely, a radioimmunassay (RIA) should be developed. Various antigen preparations were compared to one another. The immune serums used in the RIA came from guinea pigs with a RSV antibody titer of up to 320 in the complement binding reaction. A number of observations lead to the discussion of the possibility of the formation (incomplete) of cross-reactive antibodies between virus and host cell. This hypothesis could be well supported through references in the literature. Under the assumption of the existence of cross-reactive antibodies, a further model of the pathogenesis of the RSV illness allows itself to be developed, which could be preceived as an illness with autoimmune components. With this model the varying courses of this disease in different age groups can be easily explained. (orig.) [de

Swine Influenza Virus Antibodies in Humans, Western Europe, 2009

Science.gov (United States)

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

2011-01-01

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

Generation and Characterization of Novel Human IRAS Monoclonal Antibodies

Directory of Open Access Journals (Sweden)

Bo Wang

2009-01-01

Full Text Available Imidazoline receptors were first proposed by Bousquet et al., when they studied antihypertensive effect of clonidine. A strong candidate for I1R, known as imidazoline receptor antisera-selected protein (IRAS, has been cloned from human hippocampus. We reported that IRAS mediated agmatine-induced inhibition of opioid dependence in morphine-dependent cells. To elucidate the functional and structure properties of I1R, we developed the newly monoclonal antibody against the N-terminal hIRAS region including the PX domain (10–120aa through immunization of BALB/c mice with the NusA-IRAS fusion protein containing an IRAS N-terminal (10–120aa. Stable hybridoma cell lines were established and monoclonal antibodies specifically recognized full-length IRAS proteins in their native state by immunoblotting and immunoprecipitation. Monoclonal antibodies stained in a predominantly punctate cytoplasmic pattern when applied to IRAS-transfected HEK293 cells by indirect immunofluorescence assays and demonstrated excellent reactivity in flow immunocytometry. These monoclonal antibodies will provide powerful reagents for the further investigation of hIRAS protein functions.

IgE antibodies in toxoplasmosis.

Science.gov (United States)

Matowicka-Karna, Joanna; Kemona, Halina

2014-05-15

Toxoplasmosis is a worldwide infection caused by the intracellular parasite Toxoplasma gondii. At least a third of the world human population is infected with the parasite, making it one of the most successful parasitic infections. Primary maternal infection may cause health-threatening sequelae for the fetus, or even cause death of the uterus. Reactivation of a latent infection in immune deficiency conditions such as AIDS and organ transplantation can cause fatal toxoplasmic encephalitis. Toxoplasmosis is a major cause of chorioretinitis, especially in individuals with impaired immune systems. In the acute phase, directly after invading the body, T. gondii begins to multiply rapidly. In the majority of cases acquired toxoplasmosis is asymptomatic. In the second week of infection, specific IgM antibodies are present in the blood. IgE antibodies appear at the same time, slightly preceding specific IgA antibodies. The concentration of IgE can be one of the parameters used for diagnosing an infection with T. gondii. Laboratory diagnosis, i.e. IgE and serologic assays, plays the main role in the diagnosis of congenital infection and assists in the confirmatory diagnosis of toxoplasmic encephalitis and ocular toxoplasmosis. This article is a review of IgE in toxoplasmosis.

Cancer imaging with radiolabeled antibodies

International Nuclear Information System (INIS)

Goldenberg, D.M.

1990-01-01

This book presents a perspective of the use of antibodies to target diagnostic isotopes to tumors. Antibodies with reasonable specificity can be developed against almost any substance. If selective targeting to cancer cells can be achieved, the prospects for a selective therapy are equally intriguing. But the development of cancer detection, or imaging, with radiolabeled antibodies has depended upon advances in a number of different areas, including cancer immunology and immunochemistry for identifying suitable antigen targets and antibodies to these targets, tumor biology for model systems, radiochemistry for he attachment of radionuclides to antibodies, molecular biology for reengineering the antibodies for safer and more effective use in humans, and nuclear medicine for providing the best imaging protocols and instrumentation to detect minute amounts of elevated radioactivity against a background of considerable noise. Accordingly, this book has been organized to address the advances that are being made in many of these areas

Direct binding to antigen-coated beads refines the specificity and cross-reactivity of four monoclonal antibodies that recognize polymorphic epitopes of HLA class I molecules.

Science.gov (United States)

Hilton, H G; Parham, P

2013-04-01

Monoclonal antibodies with specificity for human leukocyte antigen (HLA) class I determinants of HLA were originally characterized using serological assays in which the targets were cells expressing three to six HLA class I variants. Because of this complexity, the specificities of the antibodies were defined indirectly by correlation. Here we use a direct binding assay, in which the targets are synthetic beads coated with 1 of 111 HLA class I variants, representing the full range of HLA-A, -B and -C variation. We studied one monoclonal antibody with monomorphic specificity (W6/32) and four with polymorphic specificity (MA2.1, PA2.1, BB7.2 and BB7.1) and compared the results with those obtained previously. W6/32 reacted with all HLA class I variants. MA2.1 not only exhibits high specificity for HLA-A*02, -B*57 and -B*58, but also exhibited cross-reactivity with HLA-A*11 and -B*15:16. At low concentration (1 µg/ml), PA2.1 and BB7.2 were both specific for HLA-A*02 and -A*69, and at high concentration (50 µg/ml) exhibited significant cross-reactions with HLA-A*68, -A*23 and -A*24. BB7.1 exhibits specificity for HLA-B*07 and -B*42, as previously described, but reacts equally well with HLA-B*81, a rare allotype defined some 16 years after the description of BB7.1. The results obtained with cell-based and bead-based assays are consistent and, in combination with amino acid sequence comparison, increase understanding of the polymorphic epitopes recognized by the MA2.1, PA2.1, BB7.2 and BB7.1 antibodies. Comparison of two overlapping but distinctive bead sets from two sources gave similar results, but the overall levels of binding were significantly different. Several weaker reactions were observed with only one of the bead sets. © 2013 John Wiley & Sons A/S.

Evaluation of pre-existing antibody presence as a risk factor for posttreatment anti-drug antibody induction: analysis of human clinical study data for multiple biotherapeutics.

Science.gov (United States)

Xue, Li; Rup, Bonita

2013-07-01

Biotherapeutic-reactive antibodies in treatment-naïve subjects (i.e., pre-existing antibodies) have been commonly detected during clinical immunogenicity assessments; however information on pre-existing antibody prevalence, physiological effects, and impact on posttreatment anti-drug antibody (ADA) induction remains limited. In this analysis, pre-existing antibody prevalence and impact on posttreatment ADA induction were determined using ADA data from 12 biotherapeutics analyzed in 32 clinical studies. Approximately half (58%) of the biotherapeutics were associated with some level of pre-existing antibodies and 67% of those were associated with posttreatment ADA induction. Across all studies, 5.6% of study subjects demonstrated presence of pre-existing antibodies, among which, 17% of the individual subjects had posttreatment increases in their ADA titers while 16% had decreased titers and 67% had no change in titers. However, in studies conducted in the rheumatoid arthritis (RA) population, 14.8% of RA patients were associated with pre-existing antibodies and 30% of those had posttreatment titer increases. The results suggest that in most study subjects, pre-existing antibodies pose a low risk for posttreatment ADA induction. That said, the high risk of induction implicated for RA patients, primarily observed in treatments evaluating novel antibody-based constructs, indicates that further understanding of the contribution of product and disease-specific factors is needed. Cross-industry efforts to collect and analyze a larger data set would enhance understanding of the prevalence, nature, and physiological consequences of pre-existing antibodies, better inform the immunogenicity risk profiles of products associated with these antibodies and lead to better fit-for-purpose immunogenicity management and mitigation strategies.

The Effect of Lead on the Glomalin Content of Hypha and Root Reactive with Monoclonal Antibody and Bradford in both in Vitro and Pot Culture Conditions

Directory of Open Access Journals (Sweden)

Elham Malekzadeh

2017-02-01

Full Text Available Introduction: Glomalin is known as a specific fungal glycoprotein belonging to the order Glomerales in phylum Glomeromycota and has been introduced as a heat shock protein. We hypothesised that increasing the level of Pb would lead to increase in glomalin production. Glomalin is usually determined by two methods, the Bradford protein dye-binding assay and the enzyme-linked immunosorbent assay (ELISA. Since many laboratories are not equipped to carry out the ELISA assay, many studies have measured glomalin-related soil protein using the Bradford colorimetric total protein assay. While, the ELISA method specifically measures glomalin by using monoclonal antibody MAb32B11. Materials and Methods: The pot experiment was conducted in the sterile free-glomalin sand with Trifolium repens L. mycorrhized by Rhizophagus irregularis fungus and treated with the Pb levels of 0, 150, 300 and 450 µM. Thus, in vitro experiment was performed in two-compartments plates containing of the transformed carrot roots (Daucus carota L. mycorrhized with the same fungus in root compartment and hyphal compartment treated with the Pb levels of 0, 0.01, 0.1 and 1 mM as Pb(NO32. For glomalin extraction, hyphal or root samples were autoclaved at 121 ⁰C with 50 mM sodium citrate buffer for 60 min in three cycles. Protein concentrations in the extracted samples were determined using a modified Bradford protein assay. Also, glomalin content in the samples were determined by indirect ELISA using monoclonal antibody MAb32B11. The percentages of the total root length were colonised by mycorrhizal fungi in pot culture and both hyphal and spore densities in the metal-containing hyphal compartment were determined. Results and Discussion: In the in vitro culture the percentage of total hyphae and spore frequency decreased, while Bradford reactive total hyphal protein (BRHP and Immunoreactive hyphal protein (IRHP in hyphal compartment increased as the concentrations of Pb increased

Thyrotropin Receptor Antibody (TRAb)-IgM Levels Are Markedly Higher Than TRAb-IgG Levels in Graves' Disease Patients and Controls, and TRAb-IgM Production Is Related to Epstein-Barr Virus Reactivation.

Science.gov (United States)

Kumata, Keisuke; Nagata, Keiko; Matsushita, Michiko; Kuwamoto, Satoshi; Kato, Masako; Murakami, Ichiro; Fukata, Shuji; Hayashi, Kazuhiko

2016-10-01

Graves' disease is an autoimmune thyroid disorder that mainly presents as hyperthyroidism and is caused by thyrotropin receptor antibodies (TRAbs) that stimulate thyroid-stimulating hormone receptors. We previously reported that Graves' disease patients and healthy controls both had Epstein-Barr virus (EBV)-infected TRAb-positive B cells and the EBV-reactivated induction of these B cells in cultures may induce the production of TRAbs. In the present study, we quantified serum TRAb-IgG and TRAb-IgM levels in 34 Graves' disease patients and 15 controls using ELISA to elucidate the mechanisms underlying EBV-related antibody production. As expected, TRAb-IgG and TRAb-IgM levels were higher in Graves' disease patients than in controls; however, TRAb-IgM levels were significantly higher than those of TRAb-IgG levels, whereas total IgM levels were lower than total IgG levels. On the other hand, the enhanced production of TRAb-IgM was frequently observed in patients with EBV reactivation. These results are consistent with the fact that the percentage of autoreactive IgM B cells are higher than that of autoreactive IgG B cells, and support the EBV-related polyclonal B cell activation. It is necessary to clarify the biological characteristics of TRAb-IgM and the relationship between TRAb isotypes and the biology of Graves' disease.

[Reactivation of parvovirus B19 infection in an HIV-infected woman].

Science.gov (United States)

Sterpu, R; Ichou, H; Mahé, I; Mortier, E

2014-06-01

Infection by human parvovirus B19 (erythrovirus B19) is common and usually asymptomatic during childhood conferring lasting protection against a new infection. Parvovirus B19 infection may cause erythema infectiosum (5th disease) and aplastic crisis. Secondary symptomatic parvovirus B19 infection in the same patient is rare and its physiopathology is not always clear. A 48-year-old HIV-infected female patient presented within 5 years two acute episodes of parvovirus B19 infection although her CD4 cells count was above 500/mm(3). Absence of specific antibodies production after the first episode and persisting parvovirus viremia suggested viral reactivation rather than re-infection. During the second episode, specific antibodies were produced. Similarly to most DNA viruses, parvovirus B19 reactivation is possible in HIV-infected patients while effectively treated by antiretroviral therapy. Copyright © 2013 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

A three-layer immunoradiometric assay for determination of IgG subclass antibodies in Human Sera (''IgG subclass RAST'')

International Nuclear Information System (INIS)

Djurup, R.; Soendergaard, I.; Weeke, B.; University of Copenhagen, Denmark); Magnusson, C.G.M.

1984-01-01

We report the development of a three-layer immunoradiometric assay (TIRA) for measurement of IgG antibodies of all four subclasses in human sera. The first layer consists of diluted human serum, the second layer is monoclonal mouse antibodies to human IgG subclasses, and the third layer is 125 I-labelled rabbit anti-mouse IgG. Monoclonal anti-IgGI, anti-IgG3 and anti-IgG4 reacted only with their complementary IgG subclass, whereas the anti-IgG2 showed slight cross-reactivity to immunoglobins of other subclasses and classes and to light chain proteins. The observed cross-reactivity was found to be without importance, when the TIRA was applied to measurement of IgG subclass antibodies. Equipotency was established by use of appropriate dilutions of the monoclonal antibodies, and the assay was calibrated by use of human reference serum. The TIRA therefore permits reliable inter-individual and intra-individual comparisons of the IgG antibody response in all four subclasses. Non-specific binding obtained with pooled normal human serum was below 0.33%. Inter-assay coefficient of variation was between 18 and 27%. The TIRA was applied to measurement of IgG subclass antibodies to timothy grass pollen in sera from grass pollen allergies undergoing immunotherapy. (author)

Efficient generation of monoclonal antibodies from single rhesus macaque antibody secreting cells.

Science.gov (United States)

Meng, Weixu; Li, Leike; Xiong, Wei; Fan, Xuejun; Deng, Hui; Bett, Andrew J; Chen, Zhifeng; Tang, Aimin; Cox, Kara S; Joyce, Joseph G; Freed, Daniel C; Thoryk, Elizabeth; Fu, Tong-Ming; Casimiro, Danilo R; Zhang, Ningyan; A Vora, Kalpit; An, Zhiqiang

2015-01-01

Nonhuman primates (NHPs) are used as a preclinical model for vaccine development, and the antibody profiles to experimental vaccines in NHPs can provide critical information for both vaccine design and translation to clinical efficacy. However, an efficient protocol for generating monoclonal antibodies from single antibody secreting cells of NHPs is currently lacking. In this study we established a robust protocol for cloning immunoglobulin (IG) variable domain genes from single rhesus macaque (Macaca mulatta) antibody secreting cells. A sorting strategy was developed using a panel of molecular markers (CD3, CD19, CD20, surface IgG, intracellular IgG, CD27, Ki67 and CD38) to identify the kinetics of B cell response after vaccination. Specific primers for the rhesus macaque IG genes were designed and validated using cDNA isolated from macaque peripheral blood mononuclear cells. Cloning efficiency was averaged at 90% for variable heavy (VH) and light (VL) domains, and 78.5% of the clones (n = 335) were matched VH and VL pairs. Sequence analysis revealed that diverse IGHV subgroups (for VH) and IGKV and IGLV subgroups (for VL) were represented in the cloned antibodies. The protocol was tested in a study using an experimental dengue vaccine candidate. About 26.6% of the monoclonal antibodies cloned from the vaccinated rhesus macaques react with the dengue vaccine antigens. These results validate the protocol for cloning monoclonal antibodies in response to vaccination from single macaque antibody secreting cells, which have general applicability for determining monoclonal antibody profiles in response to other immunogens or vaccine studies of interest in NHPs.

A monoclonal antibody that tracks endospore formation in the microsporidium Nosema bombycis.

Directory of Open Access Journals (Sweden)

Yanhong Li

Full Text Available Nosema bombycis, the first identified microsporidium, is a destructive pathogen of the silkworm Bombyx mori and causes severe worldwide economic losses in sericulture. Major microsporidian structural proteins, such as the spore wall protein (SWP, are known to be involved in host invasion. In this study, the reactivity of the monoclonal antibody 2B10 was tested against an endospore protein of N. bombycis with a molecular weight size at 50-kDa, using Western blotting. The antigen was purified after immunoprecipitation and was further identified as EOB13320 according to MALDI-TOF MS assay. We found that EOB13320 locates to the surface of the different developmental stages of the parasite, mostly the sporoblast stage and the mature spore after immunoelectron microscopy examination. EOB13320 was also widely distributed in the developing endospore, especially at the sporoblast stage. This endospore protein also accumulated in the cytoplasm of both the merogony and sporoblast stages. These results imply that EOB13320 detected by monoclonal antibody 2B10 is expressed throughout the life cycle of the parasite, notably during the stage when the endospore is formed, and that this protein is important for spore-coat formation and parasite maintenance. Our study could be instrumental in the understanding of spore wall formation and will help to gain greater insight into the biology of this parasite.

A monoclonal antibody that tracks endospore formation in the microsporidium Nosema bombycis.

Science.gov (United States)

Li, Yanhong; Tao, Meiling; Ma, Fuping; Pan, Guoqing; Zhou, Zeyang; Wu, Zhengli

2015-01-01

Nosema bombycis, the first identified microsporidium, is a destructive pathogen of the silkworm Bombyx mori and causes severe worldwide economic losses in sericulture. Major microsporidian structural proteins, such as the spore wall protein (SWP), are known to be involved in host invasion. In this study, the reactivity of the monoclonal antibody 2B10 was tested against an endospore protein of N. bombycis with a molecular weight size at 50-kDa, using Western blotting. The antigen was purified after immunoprecipitation and was further identified as EOB13320 according to MALDI-TOF MS assay. We found that EOB13320 locates to the surface of the different developmental stages of the parasite, mostly the sporoblast stage and the mature spore after immunoelectron microscopy examination. EOB13320 was also widely distributed in the developing endospore, especially at the sporoblast stage. This endospore protein also accumulated in the cytoplasm of both the merogony and sporoblast stages. These results imply that EOB13320 detected by monoclonal antibody 2B10 is expressed throughout the life cycle of the parasite, notably during the stage when the endospore is formed, and that this protein is important for spore-coat formation and parasite maintenance. Our study could be instrumental in the understanding of spore wall formation and will help to gain greater insight into the biology of this parasite.

[Effect comparison between two ELISA kits in IgG antibody detection of Echinococcus granulosus].

Science.gov (United States)

Chu, Yan-Hong; Cai, Yu-Chun; Ai, Lin; Lu, Yan; Zhang, Jia; Chen, Jia-Xu

2013-06-01

To compare the effects of two ELISA kits on IgG antibody detection of human Echinococcus granulosus. A Total of 134 sera of patients with echinococcosis, paragonimiasis westermani, clonorchiasis sinensis, schistosomiasis japonica, and cysticercosis cellulosae, and normal persons were detected by two IgG ELISA kits produced by different companies. Furthermore, the specificity, sensitivity and cross reactivity were counted and analyzed statistically. The sensitivity and specificity were extremely high of the two kits as 100.00%. The cross-reactivity rates were 25.00% (paragonimiasis westermani), 26.09% (clonorchiasis sinensis), 10.00% (schistosomiasis japonica), and 87.5% (cysticercosis), respectively, by using the kit produced by the Combined Company in Shenzhen; the cross-reactivity rates were 5.00% (paragonimiasis westermani), 13.04% (clonorchiasis sinensis), 20.00% (schistosomiasis japonica), and 93.75% (cysticercosis) respectively, by using the kit produced by Haitai Company in Zhuhai. In addition, there was a significant difference of Paragonimus westermani detection (P 0.05) between the two kits. Both ELISA kits on IgG antibody detection of human Echinococcus granulosus have the advantages of a high sensitivity, specificity, convenience and high-speed. However, it is also in urgent need to further solve the cross-reactivity of Echinococcus granulosus with other parasites, in order to improve the accuracy of early diagnosis.

Induction of HIV neutralizing antibodies against the MPER of the HIV envelope protein by HA/gp41 chimeric protein-based DNA and VLP vaccines.

Directory of Open Access Journals (Sweden)

Ling Ye

Full Text Available Several conserved neutralizing epitopes have been identified in the HIV Env protein and among these, the MPER of gp41 has received great attention and is widely recognized as a promising target. However, little success has been achieved in eliciting MPER-specific HIV neutralizing antibodies by a number of different vaccine strategies. We investigated the ability of HA/gp41 chimeric protein-based vaccines, which were designed to enhance the exposure of the MPER in its native conformation, to induce MPER-specific HIV neutralizing antibodies. In characterization of the HA/gp41 chimeric protein, we found that by mutating an unpaired Cys residue (Cys-14 in its HA1 subunit to a Ser residue, the modified chimeric protein HA-C14S/gp41 showed increased reactivity to a conformation-sensitive monoclonal antibody against HA and formed more stable trimers in VLPs. On the other hand, HA-C14S/gp41 and HA/gp41 chimeric proteins expressed on the cell surfaces exhibited similar reactivity to monoclonal antibodies 2F5 and 4E10. Immunization of guinea pigs using the HA-C14S/gp41 DNA or VLP vaccines induced antibodies against the HIV gp41 as well as to a peptide corresponding to a segment of MPER at higher levels than immunization by standard HIV VLPs. Further, sera from vaccinated guinea pigs were found to exhibit HIV neutralizing activities. Moreover, sera from guinea pigs vaccinated by HA-C14S/gp41 DNA and VLP vaccines but not the standard HIV VLPs, were found to neutralize HIV pseudovirions containing a SIV-4E10 chimeric Env protein. The virus neutralization could be blocked by a MPER-specific peptide, thus demonstrating induction of MPER-specific HIV neutralizing antibodies by this novel vaccine strategy. These results show that induction of MPER-specific HIV neutralizing antibodies can be achieved through a rationally designed vaccine strategy.

Investigation of an algorithm for anti HCV EIA reactivity in blood donor screening in Turkey in the absence of nucleic acid amplification screening.

Science.gov (United States)

Karakoc, Ayse Esra; Berkem, Rukiye; Irmak, Hasan; Demiroz, Ali Pekcan; Yenicesu, Idil; Ertugrul, Nigar; Arslan, Önder; Kemahli, Sabri; Yilmaz, Sevinc; Ozcebe, Osman; Kara, Abdurrahman; Ozet, Gulsum; Acikgoz, Ziya Cibali; Acikgoz, Tulin

2017-10-01

In this study we aimed to propose an algorithm for initial anti HCV EIA reactive blood donations in Turkey where nucleic acid amplification tests are not yet obligatory for donor screening. A total of 416 anti HCV screening test reactive donor samples collected from 13 blood centers from three cities in Turkey were tested in duplicate by Ortho HCV Ab Version 3.0 and Radim HCV Ab. All the repeat reactive samples were tested by INNO-LIA HCV Ab 3.0 or Chiron RIBA HCV 3.0 and Abbott Real Time HCV. Intra-assay correlations were calculated with Pearson r test. ROC analysis was used to study the relationship between EIA tests and the confirmatory tests. The number of repeat reactive results with Ortho EIA were 221 (53.1%) whereas that of microEIA, 62 (14.9%). Confirmed positivity rate was 14.6% (33/226) by RIBA and 10.6% (24/226) by NAT. Reactive PCR results were predicted with 100% sensitivity and 95% specificity with S/CO levels of 8.1 with Ortho EIA and 3.4 with microEIA. Repeat reactivity rates declined with a second HCV antibody assay. Samples repeat reactive with one HCV antibody test and negative with the other were all NAT negative. All the NAT reactive samples were RIBA positive. None of the RIBA indeterminate or negative samples were NAT reactive. Considering the threshold values for EIA kits determined by ROC analysis NAT was decided to be performed for the samples above the threshold value and a validated supplemental HCV antibody test for the samples below. Copyright © 2017 Elsevier Ltd. All rights reserved.

Many de novo donor‐specific antibodies recognize β2‐microglobulin‐free, but not intact HLA heterodimers

Science.gov (United States)

Michel, K.; Santella, R.; Steers, J.; Sahajpal, A.; Downey, F. X.; Thohan, V.

2016-01-01

Abstract Solid‐phase single antigen bead (SAB) assays are standard of care for detection and identification of donor‐specific antibody (DSA) in patients who receive solid organ transplantation (SOT). While several studies have documented the reproducibility and sensitivity of SAB testing for DSA, there are little data available concerning its specificity. This study describes the identification of antibodies to β2‐microglobulin‐free human leukocyte antigen (β2‐m‐fHLA) heavy chains on SAB arrays and provides a reassessment of the clinical relevance of DSA testing by this platform. Post‐transplant sera from 55 patients who were positive for de novo donor‐specific antibodies on a SAB solid‐phase immunoassay were tested under denaturing conditions in order to identify antibodies reactive with β2‐m‐fHLA or native HLA (nHLA). Antibodies to β2‐m‐fHLA were present in nearly half of patients being monitored in the post‐transplant period. The frequency of antibodies to β2‐m‐fHLA was similar among DSA and HLA antigens that were irrelevant to the transplant (non‐DSA). Among the seven patients with clinical or pathologic antibody‐mediated rejection (AMR), none had antibodies to β2‐m‐fHLA exclusively; thus, the clinical relevance of β2‐m‐fHLA is unclear. Our data suggests that SAB testing produces false positive reactions due to the presence of β2‐m‐fHLA and these can lead to inappropriate assignment of unacceptable antigens during transplant listing and possibly inaccurate identification of DSA in the post‐transplant period. PMID:27060279

NMR Detection of Semi-Specific Antibody Interactions in Serum Environments

Directory of Open Access Journals (Sweden)

Saeko Yanaka

2017-09-01

Full Text Available Although antibody functions are executed in heterogeneous blood streams characterized by molecular crowding and promiscuous intermolecular interaction, detailed structural characterizations of antibody interactions have thus far been performed under homogeneous in vitro conditions. NMR spectroscopy potentially has the ability to study protein structures in heterogeneous environments, assuming that the target protein can be labeled with NMR-active isotopes. Based on our successful development of isotope labeling of antibody glycoproteins, here we apply NMR spectroscopy to characterize antibody interactions in heterogeneous extracellular environments using mouse IgG-Fc as a test molecule. In human serum, many of the HSQC peaks originating from the Fc backbone exhibited attenuation in intensity of various magnitudes. Similar spectral changes were induced by the Fab fragment of polyclonal IgG isolated from the serum, but not by serum albumin, indicating that a subset of antibodies reactive with mouse IgG-Fc exists in human serum without preimmunization. The metaepitopes recognized by serum polyclonal IgG cover the entire molecular surface of Fc, including the binding sites to Fc receptors and C1q. In-serum NMR observation will offer useful tools for the detailed characterization of biopharamaceuticals, including therapeutic antibodies in physiologically relevant heterogeneous environments, also giving deeper insight into molecular recognition by polyclonal antibodies in the immune system.

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

International Nuclear Information System (INIS)

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

1993-01-01

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

[Neuroimmunological diseases associated with VGKC complex antibodies].

Science.gov (United States)

Watanabe, Osamu

2013-05-01

Antibodies to voltage-gated potassium channels(VGKC) were first identified by radioimmunoassay of radioisotope labeled alpha-dendrotoxin-VGKCs solubilized from rabbit brain. These antibodies were found only in a proportion of patients with acquired neuromyotonia (Isaacs' syndrome). VGKC antibodies were also detected in Morvan's syndrome and in a form of autoimmune limbic encephalitis. Recent studies indicated that the "VGKC" antibodies are mainly directed toward associated proteins(for example LGI-1, Caspr-2) that complex with the VGKCs themselves. The "VGKC" antibodies are now usually known as VGKC-complex antibodies. In general, LGI-1 antibodies are most common in limbic encephalitis with SIADH. Caspr-2 antibodies are present in the majority of patients with Morvan's syndrome. These patients develop combinations of CNS symptoms, autonomic dysfunction, and peripheral nerve hyperexcitability.

Intracellular and non-neuronal targets of voltage-gated potassium channel complex antibodies.

Science.gov (United States)

Lang, Bethan; Makuch, Mateusz; Moloney, Teresa; Dettmann, Inga; Mindorf, Swantje; Probst, Christian; Stoecker, Winfried; Buckley, Camilla; Newton, Charles R; Leite, M Isabel; Maddison, Paul; Komorowski, Lars; Adcock, Jane; Vincent, Angela; Waters, Patrick; Irani, Sarosh R

2017-04-01

Autoantibodies against the extracellular domains of the voltage-gated potassium channel (VGKC) complex proteins, leucine-rich glioma-inactivated 1 (LGI1) and contactin-associated protein-2 (CASPR2), are found in patients with limbic encephalitis, faciobrachial dystonic seizures, Morvan's syndrome and neuromyotonia. However, in routine testing, VGKC complex antibodies without LGI1 or CASPR2 reactivities (double-negative) are more common than LGI1 or CASPR2 specificities. Therefore, the target(s) and clinical associations of double-negative antibodies need to be determined. Sera (n=1131) from several clinically defined cohorts were tested for IgG radioimmunoprecipitation of radioiodinated α-dendrotoxin ( 125 I-αDTX)-labelled VGKC complexes from mammalian brain extracts. Positive samples were systematically tested for live hippocampal neuron reactivity, IgG precipitation of 125 I-αDTX and 125 I-αDTX-labelled Kv1 subunits, and by cell-based assays which expressed Kv1 subunits, LGI1 and CASPR2. VGKC complex antibodies were found in 162 of 1131 (14%) sera. 90 of these (56%) had antibodies targeting the extracellular domains of LGI1 or CASPR2. Of the remaining 72 double-negative sera, 10 (14%) immunoprecipitated 125 I-αDTX itself, and 27 (38%) bound to solubilised co-expressed Kv1.1/1.2/1.6 subunits and/or Kv1.2 subunits alone, at levels proportionate to VGKC complex antibody levels (r=0.57, p=0.0017). The sera with LGI1 and CASPR2 antibodies immunoprecipitated neither preparation. None of the 27 Kv1-precipitating samples bound live hippocampal neurons or Kv1 extracellular domains, but 16 (59%) bound to permeabilised Kv1-expressing human embryonic kidney 293T cells. These intracellular Kv1 antibodies mainly associated with non-immune disease aetiologies, poor longitudinal clinical-serological correlations and a limited immunotherapy response. Double-negative VGKC complex antibodies are often directed against cytosolic epitopes of Kv1 subunits and occasionally against

Dissection of antibody specificities induced by yellow fever vaccination.

Directory of Open Access Journals (Sweden)

Oksana Vratskikh

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

Human IgG subclass antibodies to the 19 kilodalton carboxy ...

African Journals Online (AJOL)

IgG2 or IgG4 antibodies were virtually nonexistent. The cross-reactivity between the 4 sequence variants (E-KNG, E-TSR, Q-KNG and. Q-TSR) of MSP119 was confirmed; however, a minority of sera preferentially recognised the KNG but not the TSR variants. All 33 P. falciparum isolates from different parts ofm Uganda

Characterization of a monoclonal antibody with specificity for holo-transcobalamin

Directory of Open Access Journals (Sweden)

Fedosov Sergey N

2006-01-01

Full Text Available Abstract Background Holotranscobalamin, cobalamin-saturated transcobalamin, is the minor fraction of circulating cobalamin (vitamin B12, which is available for cellular uptake and hence is physiologically relevant. Currently, no method allows simple, direct quantification of holotranscobalamin. We now report on the identification and characterization of a monoclonal antibody with a unique specificity for holotranscobalamin. Methods The specificity and affinity of the monoclonal antibodies were determined using surface plasmon resonance and recombinant transcobalamin as well as by immobilizing the antibodies on magnetic microspheres and using native transcobalamin in serum. The epitope of the holotranscobalamin specific antibody was identified using phage display and comparison to a de novo generated three-dimensional model of transcobalamin using the program Rosetta. A direct assay for holotrnscobalamin in the ELISA format was developed using the specific antibody and compared to the commercial assay HoloTC RIA. Results An antibody exhibiting >100-fold specificity for holotranscobalamin over apotranscobalamin was identified. The affinity but not the specificity varied inversely with ionic strength and pH, indicating importance of electrostatic interactions. The epitope was discontinuous and epitope mapping of the antibody by phage display identified two similar motifs with no direct sequence similarity to transcobalamin. A comparison of the motifs with a de novo generated three-dimensional model of transcobalamin identified two structures in the N-terminal part of transcobalamin that resembled the motif. Using this antibody an ELISA based prototype assay was developed and compared to the only available commercial assay for measuring holotranscobalamin, HoloTC RIA. Conclusion The identified antibody possesses a unique specificity for holotranscobalamin and can be used to develop a direct assay for the quantification of holotranscobalamin.

The early implementation of Trypanosoma cruzi antibody screening of donors and donations within England: preempting a problem.

Science.gov (United States)

Kitchen, Alan D; Hewitt, Patricia E; Chiodini, Peter L

2012-09-01

Trypanosoma cruzi is a parasitic infection endemic in Central and Southern America, but is spreading into nonendemic countries with migration of infected individuals from endemic countries. The parasite is transmitted by transfusion or transplantation and donation screening is performed routinely in endemic countries to prevent transmission. In situations where migrants from endemic countries have settled in nonendemic countries and present as donors (blood or other cellular products), intervention is required to prevent transfusion or transplantation transmission. A screening program for T. cruzi was developed and has been used successfully for over 10 years that includes donor selection and donation screening. Donor selection criteria to identify specific risk of T. cruzi infection were developed together with laboratory screening of donations for T. cruzi antibodies and the subsequent confirmation of screen reactivity. Since the introduction of T. cruzi screening in England in 1998, a total of 38,585 donors and donations have been screened for T. cruzi antibodies, of which 223 were repeat reactive on screening and referred for confirmation: 206 confirmed negative, 14 inconclusive, and three positive. Since the move in 2005 from donor qualification to donation release testing, 15,536 donations were collected and screened, of which 15,499 (99.8%) were T. cruzi antibody negative and released to inventory. An effective program to minimize risk of the transmission of T. cruzi infection via donations has been developed and implemented. Not only does the program minimize risk of transmission, it also minimizes the cumulative, and needless, loss of donors and donations that would ensue if permanent donor deferral alone was adopted. © 2012 American Association of Blood Banks.

Identification of discriminant proteins through antibody profiling, methods and apparatus for identifying an individual

Science.gov (United States)

Thompson, Vicki S; Lacey, Jeffrey A; Gentillon, Cynthia A; Apel, William A

2015-03-03

A method for determining a plurality of proteins for discriminating and positively identifying an individual based from a biological sample. The method may include profiling a biological sample from a plurality of individuals against a protein array including a plurality of proteins. The protein array may include proteins attached to a support in a preselected pattern such that locations of the proteins are known. The biological sample may be contacted with the protein array such that a portion of antibodies in the biological sample reacts with and binds to the proteins forming immune complexes. A statistical analysis method, such as discriminant analysis, may be performed to determine discriminating proteins for distinguishing individuals. Proteins of interest may be used to form a protein array. Such a protein array may be used, for example, to compare a forensic sample from an unknown source with a sample from a known source.

Identification of discriminant proteins through antibody profiling, methods and apparatus for identifying an individual

Energy Technology Data Exchange (ETDEWEB)

Apel, William A.; Thompson, Vicki S; Lacey, Jeffrey A.; Gentillon, Cynthia A.

2016-08-09

A method for determining a plurality of proteins for discriminating and positively identifying an individual based from a biological sample. The method may include profiling a biological sample from a plurality of individuals against a protein array including a plurality of proteins. The protein array may include proteins attached to a support in a preselected pattern such that locations of the proteins are known. The biological sample may be contacted with the protein array such that a portion of antibodies in the biological sample reacts with and binds to the proteins forming immune complexes. A statistical analysis method, such as discriminant analysis, may be performed to determine discriminating proteins for distinguishing individuals. Proteins of interest may be used to form a protein array. Such a protein array may be used, for example, to compare a forensic sample from an unknown source with a sample from a known source.

EPSTEIN-BARR VIRUS INFECTIONS – AVIDITY TEST FOR IgG ANTIBODIES

Directory of Open Access Journals (Sweden)

Katja Strašek

2001-06-01

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

Neuronal antibody biomarkers for Sydenham's chorea identify a new group of children with chronic recurrent episodic acute exacerbations of tic and obsessive compulsive symptoms following a streptococcal infection.

Science.gov (United States)

Singer, Harvey S; Mascaro-Blanco, Adda; Alvarez, Kathy; Morris-Berry, Christina; Kawikova, Ivana; Ben-Pazi, Hilla; Thompson, Carol B; Ali, Syed F; Kaplan, Edward L; Cunningham, Madeleine W

2015-01-01

Several autoantibodies (anti-dopamine 1 (D1R) and 2 (D2R) receptors, anti-tubulin, anti-lysoganglioside-GM1) and antibody-mediated activation of calcium calmodulin dependent protein kinase II (CaMKII) signaling activity are elevated in children with Sydenham's chorea (SC). Recognizing proposed clinical and autoimmune similarities between SC and PANDAS (pediatric autoimmune neuropsychiatric disorder associated with a streptococcal infection), we sought to identify serial biomarker changes in a slightly different population. Antineuronal antibodies were measured in eight children (mean 11.3 years) with chronic, dramatic, recurrent tics and obsessive-compulsive disorder (OCD) associated with a group A β-hemolytic streptococcal (GABHS) respiratory tract infection, but differing because they lacked choreiform movements. Longitudinal serum samples in most subjects included two pre-exacerbation samples, Exac), one midst Exac (abrupt recurrence of tic/OCD; temporally association with a GABHS infection in six of eight subjects), and two post-Exac. Controls included four groups of unaffected children (n = 70; mean 10.8 years) obtained at four different institutions and published controls. Clinical exacerbations were not associated with a significant rise in antineuronal antibody titers. CaMKII activation was increased at the GABHS exacerbation point in 5/6 subjects, exceeded combined and published control's 95th percentile at least once in 7/8 subjects, and median values were elevated at each time point. Anti-tubulin and anti-D2R titers did not differ from published or combined control group's 95th percentile or median values. Differences in anti-lysoganglioside-GM1 and anti-D1R titers were dependent on the selected control. Variances in antibody titers and CaMKII activation were identified among the institutional control groups. Based on comparisons to published studies, results identify two groups of PANDAS: 1) a cohort, represented by this study, which lacks choreiform

Neuronal antibody biomarkers for Sydenham's chorea identify a new group of children with chronic recurrent episodic acute exacerbations of tic and obsessive compulsive symptoms following a streptococcal infection.

Directory of Open Access Journals (Sweden)

Harvey S Singer

Full Text Available Several autoantibodies (anti-dopamine 1 (D1R and 2 (D2R receptors, anti-tubulin, anti-lysoganglioside-GM1 and antibody-mediated activation of calcium calmodulin dependent protein kinase II (CaMKII signaling activity are elevated in children with Sydenham's chorea (SC. Recognizing proposed clinical and autoimmune similarities between SC and PANDAS (pediatric autoimmune neuropsychiatric disorder associated with a streptococcal infection, we sought to identify serial biomarker changes in a slightly different population. Antineuronal antibodies were measured in eight children (mean 11.3 years with chronic, dramatic, recurrent tics and obsessive-compulsive disorder (OCD associated with a group A β-hemolytic streptococcal (GABHS respiratory tract infection, but differing because they lacked choreiform movements. Longitudinal serum samples in most subjects included two pre-exacerbation samples, Exac, one midst Exac (abrupt recurrence of tic/OCD; temporally association with a GABHS infection in six of eight subjects, and two post-Exac. Controls included four groups of unaffected children (n = 70; mean 10.8 years obtained at four different institutions and published controls. Clinical exacerbations were not associated with a significant rise in antineuronal antibody titers. CaMKII activation was increased at the GABHS exacerbation point in 5/6 subjects, exceeded combined and published control's 95th percentile at least once in 7/8 subjects, and median values were elevated at each time point. Anti-tubulin and anti-D2R titers did not differ from published or combined control group's 95th percentile or median values. Differences in anti-lysoganglioside-GM1 and anti-D1R titers were dependent on the selected control. Variances in antibody titers and CaMKII activation were identified among the institutional control groups. Based on comparisons to published studies, results identify two groups of PANDAS: 1 a cohort, represented by this study, which lacks

Reactive Chlamydial Arthritis and Ophtalmopathies

Directory of Open Access Journals (Sweden)

А.К. Pavliuchenko

2015-08-01

Full Text Available Oculopathies in reactive chlamydial arthritis are diagnosed in 63 % of patients, with «conjunctivitis — uveitis — scleritis — glaucoma — cataract — keratitis» ratio as 13 : 8 : 2 : 2 : 1 : 1, and the nature of eye pathology is closely related to the severity of inflammatory process in uroge­nitalia and general activity of the disease, influences the le­vel of antichlamidial antibodies in the blood, prevalence, severity of joint syndrome and rates of its progression, development of cardiopath

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

Directory of Open Access Journals (Sweden)

Andreas Weinhäusel

2012-06-01

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

A novel ex vivo immunoproteomic approach characterising Fasciola hepatica tegumental antigens identified using immune antibody from resistant sheep.

Science.gov (United States)

Cameron, Timothy C; Cooke, Ira; Faou, Pierre; Toet, Hayley; Piedrafita, David; Young, Neil; Rathinasamy, Vignesh; Beddoe, Travis; Anderson, Glenn; Dempster, Robert; Spithill, Terry W

2017-08-01

A more thorough understanding of the immunological interactions between Fasciola spp. and their hosts is required if we are to develop new immunotherapies to control fasciolosis. Deeper knowledge of the antigens that are the target of the acquired immune responses of definitive hosts against both Fasciola hepatica and Fasciola gigantica will potentially identify candidate vaccine antigens. Indonesian Thin Tail sheep express a high level of acquired immunity to infection by F. gigantica within 4weeks of infection and antibodies in Indonesian Thin Tail sera can promote antibody-dependent cell-mediated cytotoxicity against the surface tegument of juvenile F. gigantica in vitro. Given the high protein sequence similarity between F. hepatica and F. gigantica, we hypothesised that antibody from F. gigantica-infected sheep could be used to identify the orthologous proteins in the tegument of F. hepatica. Purified IgG from the sera of F. gigantica-infected Indonesian Thin Tail sheep collected pre-infection and 4weeks p.i. were incubated with live adult F. hepatica ex vivo and the immunosloughate (immunoprecipitate) formed was isolated and analysed via liquid chromatography-electrospray ionisation-tandem mass spectrometry to identify proteins involved in the immune response. A total of 38 proteins were identified at a significantly higher abundance in the immunosloughate using week 4 IgG, including eight predicted membrane proteins, 20 secreted proteins, nine proteins predicted to be associated with either the lysosomes, the cytoplasm or the cytoskeleton and one protein with an unknown cellular localization. Three of the membrane proteins are transporters including a multidrug resistance protein, an amino acid permease and a glucose transporter. Interestingly, a total of 21 of the 38 proteins matched with proteins recently reported to be associated with the proposed small exosome-like extracellular vesicles of adult F. hepatica, suggesting that the Indonesian Thin Tail week

Differential recognition of the multiple banded antigen isoforms across Ureaplasma parvum and Ureaplasma urealyticum species by monoclonal antibodies.

Science.gov (United States)

Aboklaish, Ali F; Ahmed, Shatha; McAllister, Douglas; Cassell, Gail; Zheng, Xiaotian T; Spiller, Owen B

2016-08-01

Two separate species of Ureaplasma have been identified that infect humans: Ureaplasma parvum and Ureaplasma urealyticum. Most notably, these bacteria lack a cell wall and are the leading infectious organism associated with infection-related induction of preterm birth. Fourteen separate representative prototype bacterial strains, called serovars, are largely differentiated by the sequence of repeating units in the C-terminus of the major surface protein: multiple-banded antigen (MBA). Monoclonal antibodies that recognise single or small groups of serovars have been previously reported, but these reagents remain sequestered in individual research laboratories. Here we characterise a panel of commercially available monoclonal antibodies raised against the MBA and describe the first monoclonal antibody that cross-reacts by immunoblot with all serovars of U. parvum and U. urealyticum species. We also describe a recombinant MBA expressed by Escherichia coli which facilitated further characterisation by immunoblot and demonstrate immunohistochemistry of paraffin-embedded antigens. Immunoblot reactivity was validated against well characterised previously published monoclonal antibodies and individual commercial antibodies were found to recognise all U. parvum strains, only serovars 3 and 14 or only serovars 1 and 6, or all strains belonging to U. parvum and U. urealyticum. MBA mass was highly variable between strains, consistent with variation in the number of C-terminal repeats between strains. Antibody characterisation will enable future investigations to correlate severity of pathogenicity to MBA isoform number or mass, in addition to development of antibody-based diagnostics that will detect infection by all Ureaplasma species or alternately be able to differentiate between U. parvum, U. urealyticum or mixed infections. Copyright © 2016 Elsevier B.V. All rights reserved.

A novel rabbit anti-hepatocyte growth factor monoclonal neutralizing antibody inhibits tumor growth in prostate cancer cells and mouse xenografts

International Nuclear Information System (INIS)

Yu, Yanlan; Chen, Yicheng; Ding, Guoqing; Wang, Mingchao; Wu, Haiyang; Xu, Liwei; Rui, Xuefang; Zhang, Zhigen

2015-01-01

The hepatocyte growth factor and its receptor c-Met are correlated with castration-resistance in prostate cancer. Although HGF has been considered as an attractive target for therapeutic antibodies, the lack of cross-reactivity of monoclonal antibodies with human/mouse HGFs is a major obstacle in preclinical developments. We generated a panel of anti-HGF RabMAbs either blocking HGF/c-Met interaction or inhibiting c-Met phosphorylation. We selected one RabMAb with mouse cross-reactivity and demonstrated that it blocked HGF-stimulated downstream activation in PC-3 and DU145 cells. Anti-HGF RabMAb inhibited not only the growth of PC-3 cells but also HGF-dependent proliferation in HUVECs. We further demonstrated the efficacy and potency of the anti-HGF RabMAb in tumor xenograft mice models. Through these in vitro and in vivo experiments, we explored a novel therapeutic antibody for advanced prostate cancer. - Highlights: • HGF is an attractive target for castration-refractory prostate cancer. • We generated and characterized a panel of anti-HGF rabbit monoclonal antibodies. • More than half of these anti-HGF RabMAbs was cross-reactive with mouse HGF. • Anti-HGF RabMAb blocks HGF-stimulated phosphorylation and cell growth in vitro. • Anti-HGF RabMAb inhibits tumor growth and angiogenesis in xenograft mice

A novel rabbit anti-hepatocyte growth factor monoclonal neutralizing antibody inhibits tumor growth in prostate cancer cells and mouse xenografts

Energy Technology Data Exchange (ETDEWEB)

Yu, Yanlan; Chen, Yicheng; Ding, Guoqing; Wang, Mingchao; Wu, Haiyang; Xu, Liwei; Rui, Xuefang; Zhang, Zhigen, E-mail: srrshurology@163.com

2015-08-14

The hepatocyte growth factor and its receptor c-Met are correlated with castration-resistance in prostate cancer. Although HGF has been considered as an attractive target for therapeutic antibodies, the lack of cross-reactivity of monoclonal antibodies with human/mouse HGFs is a major obstacle in preclinical developments. We generated a panel of anti-HGF RabMAbs either blocking HGF/c-Met interaction or inhibiting c-Met phosphorylation. We selected one RabMAb with mouse cross-reactivity and demonstrated that it blocked HGF-stimulated downstream activation in PC-3 and DU145 cells. Anti-HGF RabMAb inhibited not only the growth of PC-3 cells but also HGF-dependent proliferation in HUVECs. We further demonstrated the efficacy and potency of the anti-HGF RabMAb in tumor xenograft mice models. Through these in vitro and in vivo experiments, we explored a novel therapeutic antibody for advanced prostate cancer. - Highlights: • HGF is an attractive target for castration-refractory prostate cancer. • We generated and characterized a panel of anti-HGF rabbit monoclonal antibodies. • More than half of these anti-HGF RabMAbs was cross-reactive with mouse HGF. • Anti-HGF RabMAb blocks HGF-stimulated phosphorylation and cell growth in vitro. • Anti-HGF RabMAb inhibits tumor growth and angiogenesis in xenograft mice.

Immune response to pneumococcal polysaccharides 4 and 14 in elderly and young adults. I Antibody concentrations, avidity and functional activity

Directory of Open Access Journals (Sweden)

Carlone George M

2005-06-01

Full Text Available Abstract Streptococcus pneumoniae is a serious worldwide pathogen and the focus of numerous vaccine development projects. Currently the most widely accepted surrogate marker for evaluating the efficacy of a given vaccine is to utilize ELISA. Measurement of antibody concentration by ELISA without reduction in cross-reactive antibodies causes an overestimation of antibody concentration and therefore protection, this is most notable in the aged, an at risk group for this infection. We compared the immune response to the pneumococcal polysaccharides (PPS 4 and 14 of 20 young to 20 elderly adults. Pre-and post-vaccination IgG antibody concentrations and antibody avidity against PPS4 and PPS14 were measured using two different enzyme-linked immunosorbant assay (ELISA absorption protocols. All sera were pre-absorbed with either cell-wall polysaccharide (CPS, or CPS and serotype 22F polysaccharide. Pre- and post-vaccination IgG antibody concentrations for serotype 4, but not 14, were significantly lowered with the additional absorption with serotype 22F polysaccharide in both age groups. Young and elderly demonstrated a significant increase from pre- to post-immunization antibody concentration, using either absorption method; and opsonophagocytic antibody titers in response to both PPS4 and PPS14. The correlation coefficients between ELISA and opsonophagocytic assays were improved by additional absorption with serotype 22F in response to serotype 4, but not serotype 14 in all age groups. Opsonophagocytic antibody titers in a sub-group of elderly (>77 years of age were significantly lower than the opsonophagocytic antibody concentrations in young adults. These results suggest the importance of eliminating cross-reactive antibodies from ELISA measurements by absorption of serum and an age-related impairment in the antibody response to pneumococcal polysaccharides.

Identification of a linear epitope recognized by a monoclonal antibody directed to the heterogeneous nucleoriboprotein A2

DEFF Research Database (Denmark)

Tronstrøm, Julie; Dragborg, Anette H.; Hansen, Paul Robert

2014-01-01

to as RA33. In the absence of citrulline antibodies, RA33 antibodies have been suggested to be associated with a milder disease course. In this study we screened the reactivity of a monoclonal antibody to RA33-derived peptides by modified enzyme-linked immunosorbent assays (ELISA). Terminally truncated......Rheumatoid arthritis (RA) is a chronic autoimmune disorder, characterized by progressive joint destruction and disability. Classical autoantibodies of RA are rheumatoid factors and citrulline antibodies. Patients positive for these autoantibodies are usually associated with a progressive disease...... course. A subgroup of RA patients does not express citrulline antibodies, instead are approximately 35% of these anti-citrulline-negative patients reported to express autoantibodies to the heterogeneous nucleoriboprotein A2, a ribonucleoprotein involved in RNA transport and processing also referred...

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

Science.gov (United States)

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

1992-01-01

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

A natural human monoclonal antibody targeting Staphylococcus Protein A protects against Staphylococcus aureus bacteremia

Science.gov (United States)

Varshney, Avanish K.; Sunley, Kevin M.; Bowling, Rodney A.; Kwan, Tzu-Yu; Mays, Heather R.; Rambhadran, Anu; Zhang, Yanfeng; Martin, Rebecca L.; Cavalier, Michael C.; Simard, John

2018-01-01

Staphylococcus aureus can cause devastating and life-threatening infections. With the increase in multidrug resistant strains, novel therapies are needed. Limited success with active and passive immunization strategies have been attributed to S. aureus immune evasion. Here, we report on a monoclonal antibody, 514G3, that circumvents a key S. aureus evasion mechanism by targeting the cell wall moiety Protein A (SpA). SpA tightly binds most subclasses of immunoglobulins via their Fc region, neutralizing effector function. The organism can thus shield itself with a protective coat of serum antibodies and render humoral immunity ineffective. The present antibody reactivity was derived from an individual with natural anti-SpA antibody titers. The monoclonal antibody is of an IgG3 subclass, which differs critically from other immunoglobulin subclasses since its Fc is not bound by SpA. Moreover, it targets a unique epitope on SpA that allows it to bind in the presence of serum antibodies. Consequently, the antibody opsonizes S. aureus and maintains effector function to enable natural immune mediated clearance. The data presented here provide evidence that 514G3 antibody is able to successfully rescue mice from S. aureus mediated bacteremia. PMID:29364906

Kinetics of antibody response in BALB/c and C57BL/6 mice bitten by Phlebotomus papatasi.

Directory of Open Access Journals (Sweden)

Michaela Vlkova

Full Text Available BACKGROUND: Phlebotomine sand flies are blood-sucking insects transmitting Leishmania parasites. In bitten hosts, sand fly saliva elicits specific immune response and the humoral immunity was shown to reflect the intensity of sand fly exposure. Thus, anti-saliva antibodies were suggested as the potential risk marker of Leishmania transmission. In this study, we examined the long-term kinetics and persistence of anti-Phlebotomus papatasi saliva antibody response in BALB/c and C57BL/6 mice. We also tested the reactivity of mice sera with P. papatasi salivary antigens and with the recombinant proteins. METHODOLOGY/PRINCIPAL FINDINGS: Sera of BALB/c and C57BL/6 mice experimentally bitten by Phlebotomus papatasi were tested by ELISA for the presence of anti-saliva IgE, IgG and its subclasses. We detected a significant increase of specific IgG and IgG1 in both mice strains and IgG2b in BALB/c mice that positively correlated with the number of blood-fed P. papatasi females. Using western blot and mass spectrometry we identified the major P. papatasi antigens as Yellow-related proteins, D7-related proteins, antigen 5-related proteins and SP-15-like proteins. We therefore tested the reactivity of mice sera with four P. papatasi recombinant proteins coding for most of these potential antigens (PpSP44, PpSP42, PpSP30, and PpSP28. Each mouse serum reacted with at least one of the recombinant protein tested, although none of the recombinant proteins were recognized by all sera. CONCLUSIONS: Our data confirmed the concept of using anti-sand fly saliva antibodies as a marker of sand fly exposure in Phlebotomus papatasi-mice model. As screening of specific antibodies is limited by the availability of salivary gland homogenate, utilization of recombinant proteins in such studies would be beneficial. Our present work demonstrates the feasibility of this implementation. A combination of recombinant salivary proteins is recommended for evaluation of intensity of

The interfacial character of antibody paratopes: analysis of antibody-antigen structures.

Science.gov (United States)

Nguyen, Minh N; Pradhan, Mohan R; Verma, Chandra; Zhong, Pingyu

2017-10-01

In this study, computational methods are applied to investigate the general properties of antigen engaging residues of a paratope from a non-redundant dataset of 403 antibody-antigen complexes to dissect the contribution of hydrogen bonds, hydrophobic, van der Waals contacts and ionic interactions, as well as role of water molecules in the antigen-antibody interface. Consistent with previous reports using smaller datasets, we found that Tyr, Trp, Ser, Asn, Asp, Thr, Arg, Gly, His contribute substantially to the interactions between antibody and antigen. Furthermore, antibody-antigen interactions can be mediated by interfacial waters. However, there is no reported comprehensive analysis for a large number of structured waters that engage in higher ordered structures at the antibody-antigen interface. From our dataset, we have found the presence of interfacial waters in 242 complexes. We present evidence that suggests a compelling role of these interfacial waters in interactions of antibodies with a range of antigens differing in shape complementarity. Finally, we carry out 296 835 pairwise 3D structure comparisons of 771 structures of contact residues of antibodies with their interfacial water molecules from our dataset using CLICK method. A heuristic clustering algorithm is used to obtain unique structural similarities, and found to separate into 368 different clusters. These clusters are used to identify structural motifs of contact residues of antibodies for epitope binding. This clustering database of contact residues is freely accessible at http://mspc.bii.a-star.edu.sg/minhn/pclick.html. minhn@bii.a-star.edu.sg, chandra@bii.a-star.edu.sg or zhong_pingyu@immunol.a-star.edu.sg. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Characterization of a monoclonal antibody to thymidine glycol monophosphate

International Nuclear Information System (INIS)

Chen, B.X.; Hubbard, K.; Ide, H.; Wallace, S.S.; Erlanger, B.F.

1990-01-01

A monoclonal antibody specific for thymine glycol (TG) in irradiated or OsO4-treated DNA was obtained by immunizing with thymidine glycol monophosphate (TMP-glycol) conjugated to bovine serum albumin by a carbodiimide procedure. Screening by dot-immunobinding and enzyme-linked immunosorbant assay (ELISA) procedures gave eight clones that bound OsO4- treated DNA. One of them, 2.6F.6B.6C, an IgG2a kappa, was characterized further. Hapten inhibition studies with OsO4-treated DNA showed that the antibody was specific for TMP-glycol. Among the various inhibitors tested, inhibition was in the order TMP-glycol greater than 5,6-dihydrothymidine phosphate greater than TMP greater than thymidine glycol greater than TG. Inhibition by 5,6-dihydrothymidine, thymidine, thymine, AMP, and CMP was negligible. In OsO4-treated DNA, as few as 0.5 TG per 10,000 bp were detectable by direct ELISA. Inhibition assays could detect as few as 1.5 TG per 10,000 bp. The antibody was equally reactive with native or denatured DNA containing TG. Among the X-irradiated homopolymers dC, dA, dG, and dT, only dT reacted with the antibody. Using an ELISA, the antibody could detect damage in irradiated DNA at the level of 20 Gy. Thus the antibody is of potential use in assays for DNA damage caused by X rays or other agents that damage DNA by free radical interactions

Natural and cross-inducible anti-SIV antibodies in Mauritian cynomolgus macaques.

Directory of Open Access Journals (Sweden)

Hongzhao Li

Full Text Available Cynomolgus macaques are an increasingly important nonhuman primate model for HIV vaccine research. SIV-free animals without pre-existing anti-SIV immune responses are generally needed to evaluate the effect of vaccine-induced immune responses against the vaccine epitopes. Here, in order to select such animals for vaccine studies, we screened 108 naïve female Mauritian cynomolgus macaques for natural (baseline antibodies to SIV antigens using a Bio-Plex multiplex system. The antigens included twelve 20mer peptides overlapping the twelve SIV protease cleavage sites (-10/+10, respectively (PCS peptides, and three non-PCS Gag or Env peptides. Natural antibodies to SIV antigens were detected in subsets of monkeys. The antibody reactivity to SIV was further confirmed by Western blot using purified recombinant SIV Gag and Env proteins. As expected, the immunization of monkeys with PCS antigens elicited anti-PCS antibodies. However, unexpectedly, antibodies to non-PCS peptides were also induced, as shown by both Bio-Plex and Western blot analyses, while the non-PCS peptides do not share sequence homology with PCS peptides. The presence of natural and vaccine cross-inducible SIV antibodies in Mauritian cynomolgus macaques should be considered in animal selection, experimental design and result interpretation, for their best use in HIV vaccine research.

Monoclonal antibody to DNA containing thymine glycol

Energy Technology Data Exchange (ETDEWEB)

Leadon, S A; Hanawalt, P C [Stanford Univ., CA (USA). Dept. of Biological Sciences

1983-08-01

Exposure of DNA to ionizing or near ultraviolet radiation modifies thymine to form ring-saturated products. One of the major products formed is 5,6-dihydroxy-5.6-dihydrothymine (thymine glycol). Thymine glycol can also be selectively formed by oxidizing DNA with OsO/sub 4/. We have isolated hybrids that produce monoclonal antibodies against thymine glycol by fusing mouse myeloma cells (P3X63-Ag8-6.5.3) with spleen cells from BALB/c mice immunized with OsO/sub 4/-oxidized poly(dT) complexed with methylated bovine serum albumin. This report describes the characterization of the antibody from one hybridoma using a competitive enzyme-linked immunosorbent assay (ELISA). The antibody reacted with both single- and double-stranded DNA treated with OsO/sub 4/, and with OsO/sub 4/-treated poly(dA-dT) and poly(dT); it did not crossreact with unmodified or apurinic DNA. It also reacted with DNA treated with H/sub 2/O/sub 2/ or with ..gamma..-rays at doses as low as 250 rad. We were able to detect 2 fmoles of thymine glycol in OsO/sub 4/-treated DNA and could quantitate 1 thymine glycol per 220000 thymines. Using the antibody and the ELISA, the formation and removal of thymine glycol was examined in cultures of African green monkey cells irradiated with 25 krad of ..gamma..-rays. The antibody reactive sites produced by irradiation (8.5 per 10/sup 6/ thymines) were efficiently removed from the cellular DNA.