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Sample records for induce opsonizing antibodies

  1. Opsonization of Treponema pallidum is mediated by immunoglobulin G antibodies induced only by pathogenic treponemes.

    OpenAIRE

    Shaffer, J M; Baker-Zander, S A; Lukehart, S A

    1993-01-01

    Rabbit antisera to Leptospira interrogans, Borrelia hermsii, and Treponema phagedenis biotype Reiter, reactive to shared spirochetal antigens, failed to enhance phagocytosis of Treponema pallidum by macrophages, while immunoglobulin G to Treponema pallidum subsp. pertenue and Treponema paraluiscuniculi promoted phagocytosis. Opsonic antibodies are directed to pathogen-restricted, not shared spirochetal, antigens.

  2. Opsonic and protective properties of antibodies raised to conjugate vaccines targeting six Staphylococcus aureus antigens.

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    Clarissa Pozzi

    Full Text Available Staphylococcus aureus is a major cause of nosocomial and community-acquired infections for which a vaccine is greatly desired. Antigens found on the S. aureus outer surface include the capsular polysaccharides (CP of serotype 5 (CP5 or 8 (CP8 and/or a second antigen, a β-(1→6-polymer of N-acetyl-D-glucosamine (PNAG. Antibodies specific for either CP or PNAG antigens have excellent in vitro opsonic killing activity (OPKA, but when mixed together have potent interference in OPKA and murine protection. To ascertain if this interference could be abrogated by using a synthetic non-acetylated oligosaccharide fragment of PNAG, 9GlcNH(2, in place of chemically partially deacetylated PNAG, three conjugate vaccines consisting of 9GlcNH(2 conjugated to a non-toxic mutant of alpha-hemolysin (Hla H35L, CP5 conjugated to clumping factor B (ClfB, or CP8 conjugated to iron-surface determinant B (IsdB were used separately to immunize rabbits. Opsonic antibodies mediating killing of multiple S. aureus strains were elicited for all three vaccines and showed carbohydrate antigen-specific reductions in the tissue bacterial burdens in animal models of S. aureus skin abscesses, pneumonia, and nasal colonization. Carrier-protein specific immunity was also shown to be effective in reducing bacterial levels in infected lungs and in nasal colonization. However, use of synthetic 9GlcNH(2 to induce antibody to PNAG did not overcome the interference in OPKA engendered when these were combined with antibody to either CP5 or CP8. Whereas each individual vaccine showed efficacy, combining antisera to CP antigens and PNAG still abrogated individual OPKA activities, indicating difficulty in achieving a multi-valent vaccine targeting both the CP and PNAG antigens.

  3. Serodiversity of opsonic antibodies against Enterococcus faecalis--glycans of the cell wall revisited.

    Directory of Open Access Journals (Sweden)

    Christian Theilacker

    Full Text Available In a typing system based on opsonic antibodies against carbohydrate antigens of the cell envelope, 60% of Enterococcus faecalis strains can be assigned to one of four serotypes (CPS-A to CPS-D. The structural basis for enterococcal serotypes, however, is still incompletely understood. Here we demonstrate that antibodies raised against lipoteichoic acid (LTA from a CPS-A strain are opsonic to both CPS-A and CPS-B strains. LTA-specific antibodies also bind to LTA of CPS-C and CPS-D strains, but fail to opsonize them. From CPS-C and CPS-D strains resistant to opsonization by anti-LTA, we purified a novel diheteroglycan with a repeating unit of →6-β-Galf-(1→3- β-D-Glcp-(1→ with O-acetylation in position 5 and lactic acid substitution at position 3 of the Galf residue. The purified diheteroglycan, but not LTA absorbed opsonic antibodies from whole cell antiserum against E. faecalis type 2 (a CPS-C strain and type 5 (CPS-D. Rabbit antiserum raised against purified diheteroglycan opsonized CPS-C and CPS-D strains and passive protection with diheteroglycan-specific antiserum reduced bacterial counts by 1.4-3.4 logs in mice infected with E. faecalis strains of the CPS-C and CPS-D serotype. Diheteroglycan-specific opsonic antibodies were absorbed by whole bacterial cells of E. faecalis FA2-2 (CPS-C but not by its isogenic acapsular cpsI-mutant and on native PAGE purified diheteroglycan co-migrated with the gene product of the cps-locus, suggesting that it is synthesized by this locus. In summary, two polysaccharide antigens, LTA and a novel diheteroglycan, are targets of opsonic antibodies against typeable E. faecalis strains. These cell-wall associated polymers are promising candidates for active and passive vaccination and add to our armamentarium to fight this important nosocomial pathogen.

  4. Opsonization of Cryptococcus neoformans by a family of isotype-switch variant antibodies specific for the capsular polysaccharide.

    Science.gov (United States)

    Schlageter, A M; Kozel, T R

    1990-06-01

    A family of immunoglobulin isotype-switch variants was isolated by sib selection from a murine hybridoma which produced an immunoglobulin G subclass 1 (IgG1) antibody specific for the capsular polysaccharide of Cryptococcus neoformans. Antibodies of the IgG1, IgG2a, and IgG2b isotypes had similar serotype specificity patterns in double immunodiffusion assays which used polysaccharides of the four cryptococcal serotypes as antigens. A quantitative difference in the ability of the isotypes to form a precipitate with the polysaccharide was observed in a double immunodiffusion assay and confirmed in a quantitative precipitin assay. The relative precipitating activity of the antibodies was IgG2a greater than IgG1 much greater than IgG2b. Analysis by enzyme-linked immunosorbent assay of the reactivity of the three isotypes with cryptococcal polysaccharide showed identical titers and slopes, suggesting that the variable region of the class-switch antibodies was unaltered. This system allowed us to examine the effect of the Fc portion of the antibody on opsonization of encapsulated cryptococci. Yeast cells were precoated with antibodies of each isotype and incubated with murine macrophages or cultured human monocytes. Antibodies of all three isotypes exhibited a dose-dependent opsonization for phagocytosis by both human and murine phagocytes. The relative opsonic activity of the antibodies was IgG2a greater than IgG1 greater than IgG2b.

  5. Reduced Treponema pallidum-Specific Opsonic Antibody Activity in HIV-Infected Patients With Syphilis.

    Science.gov (United States)

    Marra, Christina M; Tantalo, Lauren C; Sahi, Sharon K; Dunaway, Shelia B; Lukehart, Sheila A

    2016-04-15

    Human immunodeficiency virus (HIV)-infected individuals may have poorer serological responses to syphilis treatment and may be more likely to experience neurosyphilis. Treponema pallidum is cleared from sites of infection by opsonization, ingestion, and killing by macrophages. Serum samples from 235 individuals with syphilis were tested for T. pallidum-specific opsonic activity. Blood T. pallidum concentrations were determined by real-time polymerase chain reaction amplification of the tp0574 gene, and T. pallidum was detected in cerebrospinal fluid (CSF) by reverse-transcriptase polymerase chain reaction of 16S ribosomal RNA. Opsonic activity was higher with higher serum rapid plasma reagin titers (P pallidum was detectable, those with the highest opsonic activity had lower blood T. pallidum concentrations. In multivariable analyses, there was not a significant relationship between opsonic activity and detection of T. pallidum in CSF or CSF-VDRL reactivity. Serum T. pallidum-specific opsonic activity is significantly lower in HIV-infected individuals. Impaired T. pallidum-specific immune responses could contribute to differences in the course of disease or treatment response. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  6. Reduced Treponema pallidum–Specific Opsonic Antibody Activity in HIV-Infected Patients With Syphilis

    Science.gov (United States)

    Marra, Christina M.; Tantalo, Lauren C.; Sahi, Sharon K.; Dunaway, Shelia B.; Lukehart, Sheila A.

    2016-01-01

    Background. Human immunodeficiency virus (HIV)–infected individuals may have poorer serological responses to syphilis treatment and may be more likely to experience neurosyphilis. Treponema pallidum is cleared from sites of infection by opsonization, ingestion, and killing by macrophages. Methods. Serum samples from 235 individuals with syphilis were tested for T. pallidum–specific opsonic activity. Blood T. pallidum concentrations were determined by real-time polymerase chain reaction amplification of the tp0574 gene, and T. pallidum was detected in cerebrospinal fluid (CSF) by reverse-transcriptase polymerase chain reaction of 16S ribosomal RNA. Results. Opsonic activity was higher with higher serum rapid plasma reagin titers (P pallidum was detectable, those with the highest opsonic activity had lower blood T. pallidum concentrations. In multivariable analyses, there was not a significant relationship between opsonic activity and detection of T. pallidum in CSF or CSF-VDRL reactivity. Conclusions. Serum T. pallidum–specific opsonic activity is significantly lower in HIV-infected individuals. Impaired T. pallidum–specific immune responses could contribute to differences in the course of disease or treatment response. PMID:26655298

  7. Association of serum bactericidal antibody and opsonic antibody levels after Neisseria meningitidis serogroup C conjugate vaccine in Brazilian children and adolescents infected or not infected with HIV.

    Science.gov (United States)

    Pereira-Manfro, Wânia F; Alvino, Raquel M; Cruz, Aline C; Silva, Giselle P; Castro, Raquel B N; Ferreira, Bianca; Barreto, Daniella M; Frota, Ana Cristina C; Hofer, Cristina B; Milagres, Lucimar G

    2016-12-07

    Neisseria meningitidis serogroup C (MenC) is the main causative agent of meningitis in Brazil. HIV infection affects the quality of the immune system. HIV + children have an increased risk of infection to encapsulated bacteria such as N. meningitidis. We evaluated the opsonic antibody (OPA) levels and its correlation with serum bactericidal antibody (SBA) levels induced by one and two doses of a MenC conjugate vaccine in children and adolescents HIV + and HIV-exposed but uninfected children (HEU) group. Overall the data show the importance of two doses of vaccine for HIV + individuals. About 79% and 58% of HIV + patients showed SBA and OPA positive response after two doses of vaccine, respectively. For HEU group, 62% and 41% of patients showed SBA and OPA positive response after one dose of vaccine, respectively. A positive and significant association between SBA and OPA levels was seen after two doses of vaccine in HIV + patients. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Anti-Pseudomonas aeruginosa IgY antibodies promote bacterial opsonization and augment the phagocytic activity of polymorphonuclear neutrophils

    DEFF Research Database (Denmark)

    Thomsen, Kim; Christophersen, Lars; Jensen, Peter Østrup

    2016-01-01

    Moderation of polymorphonuclear neutrophils (PMNs) as part of a critical defense against invading pathogens may offer a promising therapeutic approach to supplement the antibiotic eradication of Pseudomonas aeruginosa infection in non-chronically infected cystic fibrosis (CF) patients. We have...... observed that egg yolk antibodies (IgY) harvested from White leghorn chickens that target P. aeruginosa opsonize the pathogen and enhance the PMN-mediated respiratory burst and subsequent bacterial killing in vitro. The effects on PMN phagocytic activity were observed in different Pseudomonas aeruginosa...

  9. Specific opsonic activity for staphylococci in peritoneal dialysis effluent during continuous ambulatory peritoneal dialysis

    DEFF Research Database (Denmark)

    Nielsen, H; Espersen, F; Kharazmi, A

    1992-01-01

    In a prospective study of intraperitoneal opsonins in 30 patients undergoing continuous ambulatory peritoneal dialysis (CAPD), the IgG concentration, the fibronectin concentration, the specific antistaphylococcal antibody level, and the opsonic activity against Staphylococcus epidermidis were...

  10. Neutrophils extracellular traps damage Naegleria fowleri trophozoites opsonized with human IgG.

    Science.gov (United States)

    Contis-Montes de Oca, A; Carrasco-Yépez, M; Campos-Rodríguez, R; Pacheco-Yépez, J; Bonilla-Lemus, P; Pérez-López, J; Rojas-Hernández, S

    2016-08-01

    Naegleria fowleri infects humans through the nasal mucosa causing a disease in the central nervous system known as primary amoebic meningoencephalitis (PAM). Polymorphonuclear cells (PMNs) play a critical role in the early phase of N. fowleri infection. Recently, a new biological defence mechanism called neutrophil extracellular traps (NETs) has been attracting attention. NETs are composed of nuclear DNA combined with histones and antibacterial proteins, and these structures are released from the cell to direct its antimicrobial attack. In this work, we evaluate the capacity of N. fowleri to induce the liberation of NETs by human PMN cells. Neutrophils were cocultured with unopsonized or IgG-opsonized N. fowleri trophozoites. DNA, histone, myeloperoxidase (MPO) and neutrophil elastase (NE) were stained, and the formation of NETs was evaluated by confocal microscopy and by quantifying the levels of extracellular DNA. Our results showed N. fowleri induce the liberation of NETs including release of MPO and NE by human PMN cells as exposure interaction time is increased, but N. fowleri trophozoites evaded killing. However, when trophozoites were opsonized, they were susceptible to the neutrophils activity. Therefore, our study suggests that antibody-mediated PMNs activation through NET formation may be crucial for antimicrobial responses against N. fowleri. © 2016 John Wiley & Sons Ltd.

  11. Live Oral Salmonella enterica Serovar Typhi Vaccines Ty21a and CVD 909 Induce Opsonophagocytic Functional Antibodies in Humans That Cross-React with S. Paratyphi A and S. Paratyphi B

    OpenAIRE

    Wahid, Rezwanul; Zafar, Shah J.; McArthur, Monica A.; Pasetti, Marcela F.; Levine, Myron M.; Sztein, Marcelo B.

    2014-01-01

    Live oral Salmonella enterica serovar Typhi vaccine Ty21a induces specific antibodies that cross-react against Salmonella enterica serovar Paratyphi A and Salmonella enterica serovar Paratyphi B, although their functional role in clearance remains unknown. We utilized an in vitro assay with THP-1 macrophages to compare the phagocytosis and survival of Salmonella opsonized with heat-inactivated human sera obtained before and after vaccination with Ty21a or a live oral S. Typhi vaccine, CVD 909...

  12. Natural antibodies in normal human serum inhibit Staphylococcus aureus capsular polysaccharide vaccine efficacy.

    Science.gov (United States)

    Skurnik, David; Kropec, Andrea; Roux, Damien; Theilacker, Christian; Huebner, Johannes; Pier, Gerald B

    2012-11-01

    Vaccines against Streptococcus pneumoniae, Neisseria meningitidis, and Hemophilus influenzae type b induce functional opsonic or bactericidal antibodies to surface capsular polysaccharides (CP). Targeting the comparable Staphylococcus aureus CP seems logical, but to date such efforts have failed in human trials. Studies using immunization-induced animal antibodies have documented interference in opsonic and protective activities of antibodies to CP by antibodies to another S. aureus cell surface polysaccharide, poly-N-acetyl glucosamine (PNAG). Here we evaluated whether natural antibody to PNAG in normal human serum (NHS) had a similar deleterious effect. Functional and/or protective activities of antibody to S. aureus CP and PNAG antigens in patients with bacteremia, in mice immunized with combinations of CP and PNAG conjugate vaccines, and in serum samples of healthy subjects with natural antibody to PNAG, to which immunization-induced animal antibodies to CP antigens were added, were evaluated. Antibodies to PNAG and CP that mutually interfered with opsonic killing of S. aureus were detected in 9 of 15 bacteremic patients. Active immunization of mice with combinations of PNAG and CP conjugate antigens always induced antibodies that interfered with each other's functional activity. Non-opsonic natural antibodies to PNAG found in NHS interfered with the functional and protective activities of immunization-induced antibody to CP antigens during experimental infection with S. aureus. Both immunization-induced animal antibodies and natural antibodies to PNAG in NHS interfere with the protective activities of immunization-induced antibody to S. aureus CP5 and CP8 antigens, representing potential barriers to successful use of CP-specific vaccines.

  13. Radiation Induced Immune Response in Prostate Cancer

    Science.gov (United States)

    2014-12-01

    dependent cell- mediated phagocytosis ( ADCP ). This research will allow us to characterize antigens and antibodies intended for clinical trials in patients...Moreover, TIP1 is inducible in nearly all mouse models of cancer resulting in opsonization and activation of ADCC and ADCP . Antibodies that we...antibody-dependent cell-mediated phagocytosis ( ADCP ). ScFv antibodies Overall Project Summary Subtask 1.1 Binding of antibodies to irradiated

  14. Microglial responses to amyloid β peptide opsonization and indomethacin treatment

    Directory of Open Access Journals (Sweden)

    Leonard Brian

    2005-08-01

    Full Text Available Abstract Background Recent studies have suggested that passive or active immunization with anti-amyloid β peptide (Aβ antibodies may enhance microglial clearance of Aβ deposits from the brain. However, in a human clinical trial, several patients developed secondary inflammatory responses in brain that were sufficient to halt the study. Methods We have used an in vitro culture system to model the responses of microglia, derived from rapid autopsies of Alzheimer's disease patients, to Aβ deposits. Results Opsonization of the deposits with anti-Aβ IgG 6E10 enhanced microglial chemotaxis to and phagocytosis of Aβ, as well as exacerbated microglial secretion of the pro-inflammatory cytokines TNF-α and IL-6. Indomethacin, a common nonsteroidal anti-inflammatory drug (NSAID, had no effect on microglial chemotaxis or phagocytosis, but did significantly inhibit the enhanced production of IL-6 after Aβ opsonization. Conclusion These results are consistent with well known, differential NSAID actions on immune cell functions, and suggest that concurrent NSAID administration might serve as a useful adjunct to Aβ immunization, permitting unfettered clearance of Aβ while dampening secondary, inflammation-related adverse events.

  15. Live oral Salmonella enterica serovar Typhi vaccines Ty21a and CVD 909 induce opsonophagocytic functional antibodies in humans that cross-react with S. Paratyphi A and S. Paratyphi B.

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    Wahid, Rezwanul; Zafar, Shah J; McArthur, Monica A; Pasetti, Marcela F; Levine, Myron M; Sztein, Marcelo B

    2014-03-01

    Live oral Salmonella enterica serovar Typhi vaccine Ty21a induces specific antibodies that cross-react against Salmonella enterica serovar Paratyphi A and Salmonella enterica serovar Paratyphi B, although their functional role in clearance remains unknown. We utilized an in vitro assay with THP-1 macrophages to compare the phagocytosis and survival of Salmonella opsonized with heat-inactivated human sera obtained before and after vaccination with Ty21a or a live oral S. Typhi vaccine, CVD 909. Opsonization with postvaccination sera predominantly increased the phagocytosis of S. Typhi relative to the corresponding prevaccination sera, and increases were also observed with S. Paratyphi A and S. Paratyphi B, albeit of lower magnitudes. Relative to prevaccination sera, opsonization with the postvaccination sera reduced the survival inside macrophages of S. Typhi but not of S. Paratyphi A or S. Paratyphi B. Higher anti-S. Typhi O antigen (lipopolysaccharide [LPS]) IgG, but not IgA, antibody titers correlated significantly with postvaccination increases in opsonophagocytosis. No differences were observed between immunization with four doses of Ty21a or one dose of CVD 909. Ty21a and CVD 909 induced cross-reactive functional antibodies, predominantly against S. Typhi. IgG anti-LPS antibodies may be important in phagocytic clearance of these organisms. Therefore, measurement of functional antibodies might be important in assessing the immunogenicity of a new generation of typhoid and paratyphoid A vaccines. (The CVD 909 study has been registered at ClinicalTrials.gov under registration no. NCT00326443.).

  16. Complement-Opsonized HIV-1 Overcomes Restriction in Dendritic Cells.

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    Wilfried Posch

    2015-06-01

    Full Text Available DCs express intrinsic cellular defense mechanisms to specifically inhibit HIV-1 replication. Thus, DCs are productively infected only at very low levels with HIV-1, and this non-permissiveness of DCs is suggested to go along with viral evasion. We now illustrate that complement-opsonized HIV-1 (HIV-C efficiently bypasses SAMHD1 restriction and productively infects DCs including BDCA-1 DCs. Efficient DC infection by HIV-C was also observed using single-cycle HIV-C, and correlated with a remarkable elevated SAMHD1 T592 phosphorylation but not SAMHD1 degradation. If SAMHD1 phosphorylation was blocked using a CDK2-inhibitor HIV-C-induced DC infection was also significantly abrogated. Additionally, we found a higher maturation and co-stimulatory potential, aberrant type I interferon expression and signaling as well as a stronger induction of cellular immune responses in HIV-C-treated DCs. Collectively, our data highlight a novel protective mechanism mediated by complement opsonization of HIV to effectively promote DC immune functions, which might be in the future exploited to tackle HIV infection.

  17. Reduction of Streptococcus pneumoniae Colonization and Dissemination by a Nonopsonic Capsular Polysaccharide Antibody

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    Christopher R. Doyle

    2016-02-01

    Full Text Available Streptococcus pneumoniae colonization of the nasopharynx (NP is a prerequisite for invasive pneumococcal disease (IPD. The marked reduction in IPD that followed the routine use of pneumococcal polysaccharide conjugate vaccines (PCVs has been linked to reduced NP colonization with vaccine-included serotypes (STs, with the caveat that PCVs are less effective against pneumonia than against IPD. Although PCV-elicited opsonic antibodies that enhance phagocytic killing of the homologous ST are considered a key correlate of PCV-mediated protection, recent studies question this relationship for some STs, including ST3. Studies with monoclonal antibodies (MAbs to the pneumococcal capsular polysaccharide (PPS of ST3 (PPS3 have shown that nonopsonic, as well as opsonic, antibodies can each protect mice against pneumonia and sepsis, but the effect of these types of MAbs on NP colonization is unknown. In this study, we determined the effects of protective opsonic and nonopsonic PPS3 MAbs on ST3 NP colonization in mice. Our results show that a nonopsonic MAb reduced early NP colonization and prevented ST3 dissemination to the lungs and blood, but an opsonic MAb did not. Moreover, the opsonic MAb induced a proinflammatory NP cytokine response, but the nonopsonic MAb had an antiinflammatory effect. The effect of the nonopsonic MAb on colonization did not require its Fc region, but its antiinflammatory effect did. Our findings challenge the paradigm that opsonic MAbs are required to prevent NP colonization and suggest that further studies of the activity of nonopsonic antibodies could advance our understanding of mechanisms of PCV efficacy and provide novel correlates of protection.

  18. Viral aggregating and opsonizing activity in collectin trimers

    DEFF Research Database (Denmark)

    Hartshorn, Kevan L; White, Mitchell R; Tecle, Tesfaldet

    2010-01-01

    of bovine serum collectin CL-46 induces aggregation of influenza A virus (IAV) and potently increases IAV uptake by neutrophils. CL-46-NCRD showed calcium-dependent and sugar-sensitive binding to both neutrophils and IAV. Replacement of specific residues of the CRD of human SP-D with those found in bovine...... serum collectins conferred opsonizing activity. The most effective substitution involved replacement of arginine 343 with valine (hSP-D-NCRD/R343V). hSP-D-NCRD/R343V greatly increased viral uptake by neutrophils and monocytes and also potentiated neutrophil respiratory burst responses. These effects...... for IAV even in the absence of the collagen domain or higher order multimerization. This may involve increased affinity of individual CRDs for glycoconjugates displayed on host cells or the viral envelope. Key words: influenza virus, neutrophil, CL-46....

  19. Comparison of the composition and opsonic activities of imported ...

    African Journals Online (AJOL)

    We compared the composition and opsonic activities for two common microbial pathogens (Staphylococcus aureus and Streptococcus pyogenes) of various imported intravenous (IV) (Sandoglobulin, Octagam and Gammagard) and intramuscular (IM) (Beriglobin and Globuman Berna) immunoglobulin (Ig) preparations with ...

  20. Human papillomavirus vaccination induces neutralising antibodies in oral mucosal fluids.

    Science.gov (United States)

    Handisurya, A; Schellenbacher, C; Haitel, A; Senger, T; Kirnbauer, R

    2016-02-16

    Mucosal human papillomaviruses (HPV) are a major cause of cancers and papillomas of the anogenital and oropharyngeal tract. HPV-vaccination elicits neutralising antibodies in sera and cervicovaginal secretions and protects uninfected individuals from persistent anogenital infection and associated diseases caused by the vaccine-targeted HPV types. Whether immunisation can prevent oropharyngeal infection and diseases and whether neutralising antibodies represent the correlate of protection, is still unclear. We determined IgG and neutralising antibodies against low-risk HPV6 and high-risk HPV16/18 in sera and oral fluids from healthy females (n=20) before and after quadrivalent HPV-vaccination and compared the results with non-vaccinated controls. HPV-vaccination induced type-specific antibodies in sera and oral fluids of the vaccinees. Importantly, the antibodies in oral fluids were capable of neutralising HPV pseudovirions in vitro, indicating protection from infection. The increased neutralising antibody levels against HPV16/18 in sera and oral fluids post-vaccination correlated significantly within an individual. We provide experimental proof that HPV-vaccination elicits neutralising antibodies to the vaccine-targeted types in oral fluids. Hence, immunisation may confer direct protection against type-specific HPV infection and associated diseases of the oropharyngeal tract. Measurement of antibodies in oral fluids represents a suitable tool to assess vaccine-induced protection within the mucosal milieu of the orophayrynx.

  1. Human papillomavirus vaccination induces neutralising antibodies in oral mucosal fluids

    Science.gov (United States)

    Handisurya, A; Schellenbacher, C; Haitel, A; Senger, T; Kirnbauer, R

    2016-01-01

    Background: Mucosal human papillomaviruses (HPV) are a major cause of cancers and papillomas of the anogenital and oropharyngeal tract. HPV-vaccination elicits neutralising antibodies in sera and cervicovaginal secretions and protects uninfected individuals from persistent anogenital infection and associated diseases caused by the vaccine-targeted HPV types. Whether immunisation can prevent oropharyngeal infection and diseases and whether neutralising antibodies represent the correlate of protection, is still unclear. Methods: We determined IgG and neutralising antibodies against low-risk HPV6 and high-risk HPV16/18 in sera and oral fluids from healthy females (n=20) before and after quadrivalent HPV-vaccination and compared the results with non-vaccinated controls. Results: HPV-vaccination induced type-specific antibodies in sera and oral fluids of the vaccinees. Importantly, the antibodies in oral fluids were capable of neutralising HPV pseudovirions in vitro, indicating protection from infection. The increased neutralising antibody levels against HPV16/18 in sera and oral fluids post-vaccination correlated significantly within an individual. Conclusions: We provide experimental proof that HPV-vaccination elicits neutralising antibodies to the vaccine-targeted types in oral fluids. Hence, immunisation may confer direct protection against type-specific HPV infection and associated diseases of the oropharyngeal tract. Measurement of antibodies in oral fluids represents a suitable tool to assess vaccine-induced protection within the mucosal milieu of the orophayrynx. PMID:26867163

  2. Opsonic activity of specific human IgG against Helicobacter pylori.

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    Tosi, M F; Czinn, S J

    1990-07-01

    There is a strong association between chronic gastroduodenal disease in adults and children and the recovery of Helicobacter pylori (formerly Campylobacter pylori) from gastric biopsy specimens. However, data relevant to host defense mechanisms directed against this organism are scarce. The ability of H. pylori-specific antibody and complement to enhance the in vitro phagocytosis and killing of H. pylori by human peripheral blood polymorphonuclear leukocytes (PMNL) were studied. Sera with IgG antibody to H. pylori from five children with culture-proven H. pylori gastric disease markedly enhanced complement-dependent phagocytosis of H. pylori in an assay using flow cytometry to measure uptake of fluorescent-labeled bacteria by PMNL. Absorption of specific antibody from patient sera with an excess of H. pylori organisms completely abrogated this enhancement. IgG purified from plasma with high IgG antibody titers to H. pylori enhanced complement-dependent phagocytosis of H. pylori and increased the killing of this organism by PMNL in the presence of 5% human opsonic complement by one full log. IgG antibody to H. pylori appears to be highly functional in vitro in promoting complement-dependent phagocytosis and killing of H. pylori by PMNL.

  3. Interactions of opsonized immune complexes with whole blood cells: binding to erythrocytes restricts complex uptake by leucocyte populations

    DEFF Research Database (Denmark)

    Nielsen, C H; Svehag, S E; Marquart, H V

    1994-01-01

    The binding of opsonized, fluorescein-labelled bovine serum albumin (BSA)/rabbit anti-BSA complexes (IC) to washed human whole blood cells and isolated leucocytes in the presence of autologous serum was investigated by flow cytometry. In the presence of erythrocytes (E), the IC-binding to granulo......The binding of opsonized, fluorescein-labelled bovine serum albumin (BSA)/rabbit anti-BSA complexes (IC) to washed human whole blood cells and isolated leucocytes in the presence of autologous serum was investigated by flow cytometry. In the presence of erythrocytes (E), the IC...... binding, the main contributors being B cells. E initially inhibited and then later enhanced the IC binding to lymphocytes, suggesting that E promote B cell uptake of C3d,g-covered IC via CR2. Our findings, that E can restrict the IC uptake by circulating leucocytes, and that an IC-induced degranulation...

  4. Preparation of monoclonal antibodies against radiation-induced protein

    International Nuclear Information System (INIS)

    Nozawa, R.; Tanaka, A.; Watanabe, H.; Kitayama, S.

    1992-01-01

    We obtained the 6 monoclonal antibodies against gamma-induced proteins of Deinococcus radiodurans, and these antibodies were designated as Mab-3F, 4B, 4D, 4F, 4G and 12G. Using these antibodies, we investigated the relations between gamma-induced proteins and other stress protein in strain R1, and the induction of proteins were compared among strain R1, resistant mutant (rec1) and radiosensitive mutant (rec30). We found new 6 proteins recognized by these monoclonal antibodies which were induced after gamma-irradiation especially in strain R1 and rec 1, but not induced in strain rec30. We suppose that these proteins participate in repair of DNA damages including double strand breaks caused by gamma-irradiation. One of them was around 46kDa protein band recognized by Mab-12G, and this protein was so induced in a large quantity after irradiation that the protein could detect by gold staining. In addition to this observation, we found some proteins which were induced in R1 and rec 1 by gamma-irradiation and other stress, but not in strain rec30, such as 31kDa protein band recognized by Mab-3F, 4B and 4G, and other 11 proteins which were especially induced in irradiated strain R1. The latter proteins might be reinforcement factor to radioresistance such as GroE and DnaK, or participant in repair of damage by gamma-irradiation in strain R1. (author)

  5. IFNγ Enhances CD64-Potentiated Phagocytosis of Treponema pallidum Opsonized with Human Syphilitic Serum by Human Macrophages

    Science.gov (United States)

    Hawley, Kelly L.; Cruz, Adriana R.; Benjamin, Sarah J.; La Vake, Carson J.; Cervantes, Jorge L.; LeDoyt, Morgan; Ramirez, Lady G.; Mandich, Daniza; Fiel-Gan, Mary; Caimano, Melissa J.; Radolf, Justin D.; Salazar, Juan C.

    2017-01-01

    Syphilis is a multi-stage, sexually transmitted disease caused by the spirochete Treponema pallidum (Tp). Considered broadly, syphilis can be conceptualized as a dualistic process in which spirochete-driven inflammation, the cause of clinical manifestations, coexists to varying extents with bacterial persistence. Inflammation is elicited in the tissues, along with the persistence of spirochetes to keep driving a robust immune response while evading host defenses; this duality is best exemplified during the florid, disseminated stage called secondary syphilis (SS). SS lesions typically contain copious amounts of spirochetes along with a mixed cellular infiltrate consisting of CD4+ T cells, CD8+ T cells, NK cells, plasma cells, and macrophages. In the rabbit model, Tp are cleared by macrophages via antibody-mediated opsonophagocytosis. Previously, we demonstrated that human syphilitic serum (HSS) promotes efficient uptake of Tp by human monocytes and that opsonophagocytosis of Tp markedly enhances cytokine production. Herein, we used monocyte-derived macrophages to study Tp–macrophage interactions ex vivo. In the absence of HSS, monocyte-derived macrophages internalized low numbers of Tp and secreted little cytokine (e.g., TNF). By contrast, these same macrophages internalized large numbers of unopsonized Borrelia burgdorferi and secreted robust levels of cytokines. Maturation of macrophages with M-CSF and IFNγ resulted in a macrophage phenotype with increased expression of HLA-DR, CD14, inducible nitric oxide synthase, TLR2, TLR8, and the Fcγ receptors (FcγR) CD64 and CD16, even in the absence of LPS. Importantly, IFNγ-polarized macrophages resulted in a statistically significant increase in opsonophagocytosis of Tp accompanied by enhanced production of cytokines, macrophage activation markers (CD40, CD80), TLRs (TLR2, TLR7, TLR8), chemokines (CCL19, CXCL10, CXCL11), and TH1-promoting cytokines (IL-12, IL-15). Finally, the blockade of FcγRs, primarily CD64

  6. Specific antibodies induce apoptosis in Trypanosoma cruzi epimastigotes.

    Science.gov (United States)

    Fernández-Presas, Ana María; Tato, Patricia; Becker, Ingeborg; Solano, Sandra; Copitin, Natalia; Kopitin, Natalia; Berzunza, Miriam; Willms, Kaethe; Hernández, Joselin; Molinari, José Luis

    2010-05-01

    The susceptibility of Trypanosoma cruzi epimastigotes to lysis by normal or immune sera in a complement-dependent reaction has been reported. Mouse immune sera depleted complement-induced damage in epimastigotes characterized by morphological changes and death. The purpose of this work was to study the mechanism of death in epimastigotes exposed to decomplemented mouse immune serum. Epimastigotes were maintained in RPMI medium. Immune sera were prepared in mice by immunization with whole crude epimastigote extracts. Viable epimastigotes were incubated with decomplemented normal or immune sera at 37 degrees C. By electron microscopy, agglutinated parasites showed characteristic patterns of membrane fusion between two or more parasites; this fusion also produced interdigitation of the subpellicular microtubules. Apoptosis was determined by flow cytometry using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and annexin V assays. Nuclear features were examined by 4'-,6-diamidino-2'-phenylindole diHCI cytochemistry that demonstrated apoptotic nuclear condensation. Caspase activity was also measured. TUNEL results showed that parasites incubated with decomplemented immune sera took up 26% of specific fluorescence as compared to 1.3% in parasites incubated with decomplemented normal sera. The Annexin-V-Fluos staining kit revealed that epimastigotes incubated with decomplemented immune sera exposed phosphatidylserine on the external leaflet of the plasma membrane. The incubation of parasites with immune sera showed caspase 3 activity. We conclude that specific antibodies are able to induce agglutination and apoptosis in epimastigotes, although the pathway is not elucidated.

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

    DEFF Research Database (Denmark)

    Karlsson, Ingrid; Borggren, Marie; Jensen, Sanne Skov

    2018-01-01

    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...... 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...

  8. Vaccine-induced antibody responses in relation to season

    NARCIS (Netherlands)

    Termorshuizen F; Sleijffers A; Hof S van den; Melker H de; Garssen J; Boland GJ; Hattum J van; Gruijl FR de; Loveren H van; LPI

    2001-01-01

    The effect of season on the antibody response after Hepatitis B (HB), Measles and Rubella vaccination in humans was investigated. In view of the immunosuppressive effects of ultraviolet radiation (UVR), especially the B-waveband (UVB), it was hypothesised that a lower antibody response after

  9. Antibody-dependent cellular cytotoxicity in antimyelin antibody-induced oligodendrocyte damage in vitro.

    Science.gov (United States)

    Griot-Wenk, M; Griot, C; Pfister, H; Vandevelde, M

    1991-08-01

    Treatment of dissociated murine brain cell cultures with an antibody recognizing galactocerebroside (GalC) led to degeneration of oligodendrocytes with loss of their cell processes. F(ab')2 fragments prepared from this antibody showed no effect. The anti-GalC antibody--but not its F(ab')2 fragments b2 was able to stimulate macrophages in these cultures as seen in a chemiluminescence assay. Therefore, antibodies bound to oligodendrocytes stimulated nearby macrophages by interacting with their Fc receptors. The oligodendroglial damage coincided with the release of toxic compounds by the stimulated macrophages, since treatment of the cultures with the anti-GalC antibody and a variety of other macrophage stimulating agents led to secretion of reactive oxygen species and--in some experiments--tumor necrosis factor, both known to be toxic for oligodendrocytes. These in vitro experiments show evidence that antibody-dependent cellular cytotoxicity may be an important mechanism of tissue destruction in inflammatory demyelinating diseases.

  10. HIV-1 infection and antibodies to Plasmodium falciparum in adults.

    Science.gov (United States)

    Hasang, Wina; Dembo, Edson G; Wijesinghe, Rushika; Molyneux, Malcolm E; Kublin, James G; Rogerson, Stephen

    2014-11-01

    Coinfection with human immunodeficiency virus (HIV) may increase susceptibility to malaria by compromising naturally acquired immunity. In 339 adults (64% HIV infected), we measured antibodies to Plasmodium falciparum variant surface antigens (VSA) and antibodies that opsonise infected erythrocytes using parasite lines FCR3, E8B, and R29, and antibodies to merozoite antigens AMA-1 and MSP2. We determined the relationship between malaria antibodies, HIV infection, markers of immune compromise, and risk of incident parasitemia. HIV-infected adults had significantly lower mean levels of opsonizing antibody to all parasite lines (P < .0001), and lower levels of antibody to AMA-1 (P = .01) and MSP2 (P < .0001). Levels of immunoglobulin G (IgG) to VSA were not affected by HIV status. Opsonising antibody titres against some isolates were positively correlated with CD4 count. There were negative associations between human immunodeficiency virus type 1 (HIV-1) viral load and opsonizing antibodies to FCR3 (P = .04), and levels of IgG to AMA-1 (P ≤ .03) and MSP2-3D7 (P = .05). Lower opsonizing antibody levels on enrollment were seen in those who became parasitemic during follow-up, independent of HIV infection (P ≤ .04 for each line). HIV-1 infection decreases opsonizing antibodies to VSA, and antibody to merozoite antigens. Opsonizing antibodies were associated with lack of parasitemia during follow up, suggesting a role in protection. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  11. Prevalence and gene characteristics of antibodies with cofactor-induced HIV-1 specificity.

    Science.gov (United States)

    Lecerf, Maxime; Scheel, Tobias; Pashov, Anastas D; Jarossay, Annaelle; Ohayon, Delphine; Planchais, Cyril; Mesnage, Stephane; Berek, Claudia; Kaveri, Srinivas V; Lacroix-Desmazes, Sébastien; Dimitrov, Jordan D

    2015-02-20

    The healthy immune repertoire contains a fraction of antibodies that bind to various biologically relevant cofactors, including heme. Interaction of heme with some antibodies results in induction of new antigen binding specificities and acquisition of binding polyreactivity. In vivo, extracellular heme is released as a result of hemolysis or tissue damage; hence the post-translational acquisition of novel antigen specificities might play an important role in the diversification of the immunoglobulin repertoire and host defense. Here, we demonstrate that seronegative immune repertoires contain antibodies that gain reactivity to HIV-1 gp120 upon exposure to heme. Furthermore, a panel of human recombinant antibodies was cloned from different B cell subpopulations, and the prevalence of antibodies with cofactor-induced specificity for gp120 was determined. Our data reveal that upon exposure to heme, ∼24% of antibodies acquired binding specificity for divergent strains of HIV-1 gp120. Sequence analyses reveal that heme-sensitive antibodies do not differ in their repertoire of variable region genes and in most of the molecular features of their antigen-binding sites from antibodies that do not change their antigen binding specificity. However, antibodies with cofactor-induced gp120 specificity possess significantly lower numbers of somatic mutations in their variable region genes. This study contributes to the understanding of the significance of cofactor-binding antibodies in immunoglobulin repertoires and of the influence that the tissue microenvironment might have in shaping adaptive immune responses. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Human papillomavirus vaccination induces neutralising antibodies in oral mucosal fluids

    OpenAIRE

    Handisurya, A; Schellenbacher, C; Haitel, A; Senger, T; Kirnbauer, R

    2016-01-01

    Background: Mucosal human papillomaviruses (HPV) are a major cause of cancers and papillomas of the anogenital and oropharyngeal tract. HPV-vaccination elicits neutralising antibodies in sera and cervicovaginal secretions and protects uninfected individuals from persistent anogenital infection and associated diseases caused by the vaccine-targeted HPV types. Whether immunisation can prevent oropharyngeal infection and diseases and whether neutralising antibodies represent the correlate of pro...

  13. Newborn infant with maternal anti-SSA antibody-induced complete heart block accompanying cardiomyopathy.

    Science.gov (United States)

    Iida, Midori; Inamura, Noboru; Takeuchi, Makoto

    2006-01-01

    Newborn case of maternal anti-SSA antibody-induced congenital complete heart block (CCHB) accompanying cardiomyopathy is presented. Unexpectedly, she died of ventricular tachycardia, not bradycardia, 6 days after birth. Autopsy revealed left ventricular cardiomyopathy with endocardial fibroelastosis. Thus, when evaluating fetal cardiac performance in cases of maternal anti-SSA antibody-induced CCHB, it is necessary to pay attention to myocardial attributes such as endocardial hyperplasia.

  14. Release of adenosine from human neutrophils stimulated by platelet activating factor, leukotriene B4 and opsonized zymosan

    Directory of Open Access Journals (Sweden)

    S. Sipka

    1992-01-01

    Full Text Available Isolated human polymorphonuclear leukocytes (PMNL stimulated by platelet activating factor (PAF, leukotriene B4 (LTB4 or opsonized zymosan (OZ released adenosine measured by thermospray high performance liquid chromatography mass spectrometry in the cell-free supernatants. Stimulation by PAF or LTB4 resulted in a bellshaped concentration-effect curve; 5 × 10−7 M PAF, 10−8 M LTB4 and 500 μg ml−1 OZ induced peak adenosine release, thus cytotoxic concentrations did not elevate adenosine level in the supernatants. Therefore adenosine release was characteristic of viable cells. As calculated from concentration-effect curves, the rank order of potency for adenosine release was PAF > LTB > OZ. These resuits suggest that adenosine, when bound specifically to membrane receptor sites, may initiate signal transduction, and, in co-operation with other inflammatory mediators, may modulate phagocyte function, e.g. production of chemoluminescence (CL.

  15. Vaccination of horses with Lyme vaccines for dogs induces short-lasting antibody responses.

    Science.gov (United States)

    Guarino, Cassandra; Asbie, Sanda; Rohde, Jennifer; Glaser, Amy; Wagner, Bettina

    2017-07-24

    Borrelia burgdorferi can induce Lyme disease. Approved Lyme vaccines for horses are currently not available. In an effort to protect horses, veterinarians are using Lyme vaccines licensed for dogs. However, data to assess the response of horses to, or determine the efficacy of this off-label vaccine use are missing. Here, antibodies against outer surface protein A (OspA), OspC, and OspF were quantified in diagnostic serum submissions from horses with a history of vaccination with canine Lyme vaccines. The results suggested that many horses respond with low and often short-lasting antibody responses. Subsequently, four experimental vaccination trials were performed. First, we investigated antibody responses to three canine vaccines in B. burgdorferi-naïve horses. One killed bacterin vaccine induced antibodies against OspC. OspA antibodies were low for all three vaccines and lasted less than 16weeks. The second trial tested the impact of the vaccine dose using the OspA/OspC inducing bacterin vaccine in horses. A 2mL dose produced higher OspA and OspC antibody values than a 1mL dose. However, the antibody response again quickly declined, independent of dose. Third, the horses were vaccinated with 2 doses of a recombinant OspA vaccine. Previous vaccination and/or environmental exposure enhanced the magnitude and longevity of the OspA antibody response to about 20weeks. Last, the influence of intramuscular versus subcutaneous vaccine administration was investigated for the recombinant OspA vaccine. OspA antibody responses were not influenced by injection route. The current work highlights that commercial Lyme vaccines for dogs induce only transient antibody responses in horses which can also be of low magnitude. Protection from infection with B. burgdorferi should not be automatically assumed after vaccinating horses with Lyme vaccines for dogs. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  16. Low-dose autologous in vitro opsonized erythrocytes. Radioimmune method and autologous opsonized erythrocytes for refractory autoimmune thrombocytopenic purpura in adults

    Energy Technology Data Exchange (ETDEWEB)

    Ambriz, R.; Munoz, R.; Pizzuto, J.; Quintanar, E.; Morales, M.; Aviles, A.

    1987-01-01

    Adult patients with chronic autoimmune thrombocytopenic purpura (ATP), which proved refractory to various treatments, received a single dose of autologous in vitro opsonized erythrocytes with 100 micrograms of anti-D IgG. In 1983, 30 of these patients were treated with autologous erythrocytes that had been opsonized and labeled with 25 mCi (740 MBq) of technetium Tc 99m; this treatment was designated as the radioimmune method. Favorable responses were noted in 36% of patients so treated. In 1985, another group of 16 patients with refractory ATP received therapy with autologous opsonized erythrocytes (AOPE) and 55% of these patients showed favorable responses. Five (17%) of the patients treated using the radioimmune method attained a complete, long-term (greater than 35 months) remission of their ATP, and five (31%) of the patients treated using AOPE remained in complete remission over 270 days after cessation of therapy. Major complications were not seen. We concluded that the interaction of macrophages with low-dose AOPE is a successful therapeutic approach in ATP refractory to standard treatment.

  17. Antibody targeting of Cathepsin S induces antibody-dependent cellular cytotoxicity

    Directory of Open Access Journals (Sweden)

    Kwok Hang Fai

    2011-12-01

    Full Text Available Abstract Background Proteolytic enzymes have been implicated in driving tumor progression by means of their cancer cell microenvironment activity where they promote proliferation, differentiation, apoptosis, migration, and invasion. Therapeutic strategies have focused on attenuating their activity using small molecule inhibitors, but the association of proteases with the cell surface during cancer progression opens up the possibility of targeting these using antibody dependent cellular cytotoxicity (ADCC. Cathepsin S is a lysosomal cysteine protease that promotes the growth and invasion of tumour and endothelial cells during cancer progression. Our analysis of colorectal cancer patient biopsies shows that cathepsin S associates with the cell membrane indicating a potential for ADCC targeting. Results Here we report the cell surface characterization of cathepsin S and the development of a humanized antibody (Fsn0503h with immune effector function and a stable in vivo half-life of 274 hours. Cathepsin S is expressed on the surface of tumor cells representative of colorectal and pancreatic cancer (23%-79% positive expression. Furthermore the binding of Fsn0503h to surface associated cathepsin S results in natural killer (NK cell targeted tumor killing. In a colorectal cancer model Fsn0503h elicits a 22% cytotoxic effect. Conclusions This data highlights the potential to target cell surface associated enzymes, such as cathepsin S, as therapeutic targets using antibodies capable of elicitingADCC in tumor cells.

  18. HIV-1 envelope glycoprotein immunogens to induce broadly neutralizing antibodies

    NARCIS (Netherlands)

    Sliepen, Kwinten; Sanders, Rogier W.

    2016-01-01

    The long pursuit for a vaccine against human immunodeficiency virus 1 (HIV-1) has recently been boosted by a number of exciting developments. An HIV-1 subunit vaccine ideally should elicit potent broadly neutralizing antibodies (bNAbs), but raising bNAbs by vaccination has proved extremely difficult

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

    Science.gov (United States)

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

    2017-07-15

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

  20. Antibody response to Mycoplasma hyopneumoniae infection in vaccinated pigs with or without maternal antibodies induced by sow vaccination.

    Science.gov (United States)

    Martelli, P; Terreni, M; Guazzetti, S; Cavirani, S

    2006-06-01

    Vaccination with bacterins is an important tool for the control of Mycoplasma hyopneumoniae infection of pigs. Because such vaccination often involves piglets that have suckled M. hyopneumoniae antibody-positive dams it is important to understand the effect of pre-existing (passively acquired) antibody on vaccine-induced immunity. To investigate this issue experimentally, 20 sows that were seronegative for M. hyopneumoniae were selected from a M. hyopneumoniae-infected herd and then randomly allocated to one of four treatment groups (five sows/group): Group A, vaccinated sows/vaccinated piglets; Group B, vaccinated sows/non-vaccinated piglets; Group C, non-vaccinated sows/vaccinated piglets; Group D, non-vaccinated sows/non-vaccinated piglets. Sows (Groups A and B) were vaccinated 14 days before farrowing and seroconverted within the next 14 days. Conversely, none of the non-vaccinated sows was seropositive at farrowing. Piglets (Groups A and C) were vaccinated when they were 7 days of age. Regardless of treatments none of the piglets had any evidence of an active immune response until many of those of Groups A and C and a few of those of Groups B and D seroconverted after it had been shown that at least some pigs of all groups had been naturally infected with a field strain of M. hyopneumoniae. This pattern of immune responsiveness (i.e. the collective results of Groups A, B, C and D) suggested that vaccination of pigs had primed their immune system for subsequent exposure to M. hyopneumoniae, and that passively acquired antibody had little or no effect on either a vaccine-induced priming or a subsequent anamnestic response. According to the statistical analysis sow serological status did not interfere with the antibody response in early vaccinated piglets. In conclusion, the results pointed out that early vaccination of piglets may assist M. hyopneumoniae control independently from the serological status of sows.

  1. HIV impairs opsonic phagocytic clearance of pregnancy-associated malaria parasites.

    Directory of Open Access Journals (Sweden)

    Jessica Keen

    2007-05-01

    Full Text Available BACKGROUND: Primigravid (PG women are at risk for pregnancy-associated malaria (PAM. Multigravid (MG women acquire protection against PAM; however, HIV infection impairs this protective response. Protection against PAM is associated with the production of IgG specific for variant surface antigens (VSA-PAM expressed by chondroitin sulfate A (CSA-adhering parasitized erythrocytes (PEs. We hypothesized that VSA-PAM-specific IgG confers protection by promoting opsonic phagocytosis of PAM isolates and that HIV infection impairs this response. METHODS AND FINDINGS: We assessed the ability of VSA-PAM-specific IgG to promote opsonic phagocytosis of CSA-adhering PEs and the impact of HIV infection on this process. Opsonic phagocytosis assays were performed using the CSA-adherent parasite line CS2 and human and murine macrophages. CS2 PEs were opsonized with plasma or purified IgG subclasses from HIV-negative or HIV-infected PG and MG Kenyan women or sympatric men. Levels of IgG subclasses specific for VSA-PAM were compared in HIV-negative and HIV-infected women by flow cytometry. Plasma from HIV-negative MG women, but not PG women or men, promoted the opsonic phagocytosis of CSA-binding PEs (p < 0.001. This function depended on VSA-PAM-specific plasma IgG1 and IgG3. HIV-infected MG women had significantly lower plasma opsonizing activity (median phagocytic index 46 [interquartile range (IQR 18-195] versus 251 [IQR 93-397], p = 0.006 and levels of VSA-PAM-specific IgG1 (mean fluorescence intensity [MFI] 13 [IQR 11-20] versus 30 [IQR 23-41], p < 0.001 and IgG3 (MFI 17 [IQR 14-23] versus 28 [IQR 23-37], p < 0.001 than their HIV-negative MG counterparts. CONCLUSIONS: Opsonic phagocytosis may represent a novel correlate of protection against PAM. HIV infection may increase the susceptibility of multigravid women to PAM by impairing this clearance mechanism.

  2. Comparisons of the effect of naturally acquired maternal pertussis antibodies and antenatal vaccination induced maternal tetanus antibodies on infant's antibody secreting lymphocyte responses and circulating plasma antibody

    Science.gov (United States)

    The goal of this study was to explore the effects of trans-placental tetanus toxoid (TT) and pertussis (PT) antibodies on an infant's response to vaccination in the context of antenatal immunization with tetanus but not with pertussis. 38 mothers received a single dose of TT vaccine during pregnancy...

  3. Binding induced conformational changes of proteins correlate with their intrinsic fluctuations: a case study of antibodies

    Directory of Open Access Journals (Sweden)

    Keskin Ozlem

    2007-05-01

    Full Text Available Abstract Background How antibodies recognize and bind to antigens can not be totally explained by rigid shape and electrostatic complimentarity models. Alternatively, pre-existing equilibrium hypothesis states that the native state of an antibody is not defined by a single rigid conformation but instead with an ensemble of similar conformations that co-exist at equilibrium. Antigens bind to one of the preferred conformations making this conformation more abundant shifting the equilibrium. Results Here, two antibodies, a germline antibody of 36–65 Fab and a monoclonal antibody, SPE7 are studied in detail to elucidate the mechanism of antibody-antigen recognition and to understand how a single antibody recognizes different antigens. An elastic network model, Anisotropic Network Model (ANM is used in the calculations. Pre-existing equilibrium is not restricted to apply to antibodies. Intrinsic fluctuations of eight proteins, from different classes of proteins, such as enzymes, binding and transport proteins are investigated to test the suitability of the method. The intrinsic fluctuations are compared with the experimentally observed ligand induced conformational changes of these proteins. The results show that the intrinsic fluctuations obtained by theoretical methods correlate with structural changes observed when a ligand is bound to the protein. The decomposition of the total fluctuations serves to identify the different individual modes of motion, ranging from the most cooperative ones involving the overall structure, to the most localized ones. Conclusion Results suggest that the pre-equilibrium concept holds for antibodies and the promiscuity of antibodies can also be explained this hypothesis: a limited number of conformational states driven by intrinsic motions of an antibody might be adequate to bind to different antigens.

  4. Cell death induced by a 131I-labeled monoclonal antibody in ovarian cancer multicell spheroids

    International Nuclear Information System (INIS)

    Filippovich, I.V.; Sorokina, N.; Robillard, N.; Faivre-Chauvet, A.; Bardies, M.; Chatal, J.F.

    1996-01-01

    Treatment of OVCAR-3 spheroids with 131 I-OC125 monoclonal antibody produced a decrease in spheroid volume and a concomitant rise in necrotic cell number. No increase in apoptotic cell number was observed during incubation of spheroids with the labeled antibody. Necrosis began early, reaching a maximum after 3 Gy of accumulated dose delivered at a dose rate of 1.8 cGy/h. Higher accumulated doses induced necrosis for longer incubation times. Thus, dose rate and time are both determinants of ultimate radiation effects when spheroids are incubated with labeled antibodies, although dose rate is the most important factor

  5. Cell death induced by a 131I-labeled monoclonal antibody in ovarian cancer multicell spheroids.

    Science.gov (United States)

    Filippovich, I V; Sorokina, N; Robillard, N; Faivre-Chauvet, A; Bardies, M; Chatal, J F

    1996-07-01

    Treatment of OVCAR-3 spheroids with 131I-OC125 monoclonal antibody produced a decrease in spheroid volume and a concomitant rise in necrotic cell number. No increase in apoptotic cell number was observed during incubation of spheroids with the labeled antibody. Necrosis began early, reaching a maximum after 3 Gy of accumulated dose delivered at a dose rate of 1.8 cGy/h. Higher accumulated doses induced necrosis for longer incubation times. Thus, dose rate and time are both determinants of ultimate radiation effects when spheroids are incubated with labeled antibodies, although dose rate is the most important factor.

  6. Anti-idiotypic antibody-induced protection against Clostridium perfringens type D.

    OpenAIRE

    Percival, D A; Shuttleworth, A D; Williamson, E D; Kelly, D C

    1990-01-01

    A monoclonal antibody (BALB/c mouse) with specificity for a neutralizing epitope on the epsilon-toxin produced by Clostridium perfringens type D was used to raise anti-idiotypic antibodies (anti-Id) in different strains of mice and rabbits. These were purified and used in cross-immunization studies to induce anti-(anti-idiotype). All strains of mice and rabbits immunized with BALB/c-derived anti-Id showed a high-titer antibody response directed towards the active site of the toxin. This prote...

  7. LIPOPOLYSACCHARIDE INDUCES THE PRODUCTION OF DIAGNOSTIC MONOCLONAL ANTIBODY BY HYBRIDOMA CELLS AGAINST CONGENITAL ADRENAL HYPERPLASIA

    Directory of Open Access Journals (Sweden)

    GEK KEE CHUA

    2017-11-01

    Full Text Available The purpose of this research is to screen and identify the potential inducers in maximizing the production of monoclonal antibody by hybridoma 192 cell line for Congenital Adrenal Hyperplasia diagnostic. There are nine inducers used in this research, namely lysozyme, aldolase, sodium butyrate, sodium phosphate, potassium phosphate, dimethyl sulfoxide, lipopolysaccharide, essential amino acids, and nonessential amino acids. Hybridoma 192 cell was cultured in 5% CO2 incubator at 37°C and ˃80% humidity in the medium with different concentrations of inducer agents. The inducers were added at the beginning of the culture and the samples were taken after 72 h of culture. The performance of these inducer agents was assessed based on the maximum monoclonal antibody titer achieved using Enzyme-linked Immunosorbent Assay. Lipopolysaccharide was found to increase the maximum monoclonal antibody titer when supplemented at 8 to 12 µg/mL. After optimization using one-factor central composite design at this range, the optimum point was determined to be 8 µg/mL. Verification experiments shows that lipopolysaccharide enhanced the average specific monoclonal antibody production rate by 56% relative to control. In conclusion, lipopolysaccharide at 8 µg/mL is able to increase the monoclonal antibody specific production of hybridoma 192 cell line.

  8. 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.

  9. Fusion proteins of HIV-1 envelope glycoprotein gp120 with CD4-induced antibodies showed enhanced binding to CD4 and CD4 binding site antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Weizao, E-mail: chenw3@mail.nih.gov [Protein Interactions Group, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702 (United States); Feng, Yang [Protein Interactions Group, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702 (United States); Wang, Yanping [Protein Interactions Group, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702 (United States); The Basic Research Program, Science Applications International Corporation-Frederick, Inc., National Cancer Institute, National Institutes of Health, Frederick, MD 21702 (United States); Zhu, Zhongyu; Dimitrov, Dimiter S. [Protein Interactions Group, Frederick National Laboratory for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702 (United States)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer Some recombinant HIV-1 gp120s do not preserve their conformations on gp140s. Black-Right-Pointing-Pointer We hypothesize that CD4i antibodies could induce conformational changes in gp120. Black-Right-Pointing-Pointer CD4i antibodies enhance binding of CD4 and CD4bs antibodies to gp120. Black-Right-Pointing-Pointer CD4i antibody-gp120 fusion proteins could have potential as vaccine immunogens. -- Abstract: Development of successful AIDS vaccine immunogens continues to be a major challenge. One of the mechanisms by which HIV-1 evades antibody-mediated neutralizing responses is the remarkable conformational flexibility of its envelope glycoprotein (Env) gp120. Some recombinant gp120s do not preserve their conformations on gp140s and functional viral spikes, and exhibit decreased recognition by CD4 and neutralizing antibodies. CD4 binding induces conformational changes in gp120 leading to exposure of the coreceptor-binding site (CoRbs). In this study, we test our hypothesis that CD4-induced (CD4i) antibodies, which target the CoRbs, could also induce conformational changes in gp120 leading to better exposed conserved neutralizing antibody epitopes including the CD4-binding site (CD4bs). We found that a mixture of CD4i antibodies with gp120 only weakly enhanced CD4 binding. However, such interactions in single-chain fusion proteins resulted in gp120 conformations which bound to CD4 and CD4bs antibodies better than the original or mutagenically stabilized gp120s. Moreover, the two molecules in the fusion proteins synergized with each other in neutralizing HIV-1. Therefore, fusion proteins of gp120 with CD4i antibodies could have potential as components of HIV-1 vaccines and inhibitors of HIV-1 entry, and could be used as reagents to explore the conformational flexibility of gp120 and mechanisms of entry and immune evasion.

  10. Fusion proteins of HIV-1 envelope glycoprotein gp120 with CD4-induced antibodies showed enhanced binding to CD4 and CD4 binding site antibodies

    International Nuclear Information System (INIS)

    Chen, Weizao; Feng, Yang; Wang, Yanping; Zhu, Zhongyu; Dimitrov, Dimiter S.

    2012-01-01

    Highlights: ► Some recombinant HIV-1 gp120s do not preserve their conformations on gp140s. ► We hypothesize that CD4i antibodies could induce conformational changes in gp120. ► CD4i antibodies enhance binding of CD4 and CD4bs antibodies to gp120. ► CD4i antibody-gp120 fusion proteins could have potential as vaccine immunogens. -- Abstract: Development of successful AIDS vaccine immunogens continues to be a major challenge. One of the mechanisms by which HIV-1 evades antibody-mediated neutralizing responses is the remarkable conformational flexibility of its envelope glycoprotein (Env) gp120. Some recombinant gp120s do not preserve their conformations on gp140s and functional viral spikes, and exhibit decreased recognition by CD4 and neutralizing antibodies. CD4 binding induces conformational changes in gp120 leading to exposure of the coreceptor-binding site (CoRbs). In this study, we test our hypothesis that CD4-induced (CD4i) antibodies, which target the CoRbs, could also induce conformational changes in gp120 leading to better exposed conserved neutralizing antibody epitopes including the CD4-binding site (CD4bs). We found that a mixture of CD4i antibodies with gp120 only weakly enhanced CD4 binding. However, such interactions in single-chain fusion proteins resulted in gp120 conformations which bound to CD4 and CD4bs antibodies better than the original or mutagenically stabilized gp120s. Moreover, the two molecules in the fusion proteins synergized with each other in neutralizing HIV-1. Therefore, fusion proteins of gp120 with CD4i antibodies could have potential as components of HIV-1 vaccines and inhibitors of HIV-1 entry, and could be used as reagents to explore the conformational flexibility of gp120 and mechanisms of entry and immune evasion.

  11. Comparisons of the effect of naturally acquired maternal pertussis antibodies and antenatal vaccination induced maternal tetanus antibodies on infant's antibody secreting lymphocyte responses and circulating plasma antibody levels.

    Science.gov (United States)

    Ahmad, Shaikh Meshbahuddin; Alam, Jahangir; Afsar, Nure Alam; Huda, Nazmul; Kabir, Yearul; Qadri, Firdausi; Raqib, Rubhana; Stephensen, Charles B

    2016-04-02

    The goal of this study was to explore the effects of trans-placental tetanus toxoid (TT) and pertussis (PT) antibodies on an infant's response to vaccination in the context of antenatal immunization with tetanus but not with pertussis. 38 mothers received a single dose of TT vaccine during pregnancy. Infants received tetanus and pertussis vaccines at 6, 10 and 14 wk of age. TT and PT anti-IgG secretion by infant lymphocytes was measured at 15 wk. Plasma antibodies were measured at 6 wk (pre-vaccination), 15 wk and 1 y of age. Prior to vaccination, TT and PT antibody were detected in 94.6% and 15.2% of infants. At 15 wk anti-TT-IgG and anti-PT-IgG in plasma was increased by 7-9 fold over pre-vaccination levels, while at 1 y plasma anti-TT-IgG was decreased by approximately 5-fold from the peak and had returned to near the pre-vaccination level. At 1 y plasma anti-PT-IgG was decreased by 2-fold 1 yfrom the 15 wk level. However, 89.5% and 82.3% of infants at 1 y had protective levels of anti-TT and anti-PT IgG, respectively. Pre-vaccination plasma IgG levels were associated with lower vaccine-specific IgG secretion by infant lymphocytes at 15 wk (p < 0.10). This apparent inhibition was seen for anti-TT-IgG at both 15 wk (p < 0.05) and t 1 y (p < 0.10) of age. In summary, we report an apparent inhibitory effect of passively derived maternal antibody on an infants' own antibody response to the same vaccine. However, since the cut-off values for protective titers are low, infants had protective antibody levels throughout infancy.

  12. Somatic Hypermutation-Induced Changes in the Structure and Dynamics of HIV-1 Broadly Neutralizing Antibodies.

    Science.gov (United States)

    Davenport, Thaddeus M; Gorman, Jason; Joyce, M Gordon; Zhou, Tongqing; Soto, Cinque; Guttman, Miklos; Moquin, Stephanie; Yang, Yongping; Zhang, Baoshan; Doria-Rose, Nicole A; Hu, Shiu-Lok; Mascola, John R; Kwong, Peter D; Lee, Kelly K

    2016-08-02

    Antibody somatic hypermutation (SHM) and affinity maturation enhance antigen recognition by modifying antibody paratope structure to improve its complementarity with the target epitope. SHM-induced changes in paratope dynamics may also contribute to antibody maturation, but direct evidence of this is limited. Here, we examine two classes of HIV-1 broadly neutralizing antibodies (bNAbs) for SHM-induced changes in structure and dynamics, and delineate the effects of these changes on interactions with the HIV-1 envelope glycoprotein (Env). In combination with new and existing structures of unmutated and affinity matured antibody Fab fragments, we used hydrogen/deuterium exchange with mass spectrometry to directly measure Fab structural dynamics. Changes in antibody structure and dynamics were positioned to improve complementarity with Env, with changes in dynamics primarily observed at the paratope peripheries. We conclude that SHM optimizes paratope complementarity to conserved HIV-1 epitopes and restricts the mobility of paratope-peripheral residues to minimize clashes with variable features on HIV-1 Env. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Propylthiouracil-Induced Vasculitis With Antineutrophil Cytoplasmic Antibody.

    Science.gov (United States)

    Criado, Paulo Ricardo; Grizzo Peres Martins, Ana Claudia; Gaviolli, Camila Fatima; Alavi, Afsaneh

    2015-06-01

    Propylthiouracil (PTU)-associated vasculitis is a potentially life-threatening disease with a recent increase in the reported cases in the medical literature. This increase may suggest that some earlier cases have been unrecognized or assigned to an alternative nosology category. Although the skin can be the only organ affected by PTU-associated vasculitis, there are many reports with multiple-system involvement. Classically, the symptoms appear under a tetrad of fever, sore throat, arthralgia, and skin lesions. Cutaneous lesions in reported cases of PTU vasculitis have most commonly consisted of retiform acral, purpuric plaques, or nodules. We report a case of perinuclear antineutrophil cytoplasmic antibody-associated vasculitis developed during treatment with PTU for Grave's disease. © The Author(s) 2014.

  14. A VAR2CSA:CSP conjugate capable of inducing dual specificity antibody responses

    DEFF Research Database (Denmark)

    Matondo, Sungwa; Thrane, Susan; Janitzek, Christoph Mikkel

    2017-01-01

    Catcher peptide. The covalent interaction between SpyTag/SpyCatcher enables the formation of DBL1x-DBL2x-ID2a:CSP conjugate vaccine. Immunogenicity and quality of antibody responses induced by the conjugate vaccine, as well as a control CSP-SpyCatcher vaccine, was tested in BALB/c mice.  Results: Serum samples...

  15. Persistence of yellow fever vaccine-induced antibodies after solid organ transplantation.

    Science.gov (United States)

    Wyplosz, B; Burdet, C; François, H; Durrbach, A; Duclos-Vallée, J C; Mamzer-Bruneel, M-F; Poujol, P; Launay, O; Samuel, D; Vittecoq, D; Consigny, P H

    2013-09-01

    Immunization using live attenuated vaccines represents a contra-indication after solid organ transplantation (SOT): consequently, transplant candidates planning to travel in countries where yellow fever is endemic should be vaccinated prior to transplantation. The persistence of yellow fever vaccine-induced antibodies after transplantation has not been studied yet. We measured yellow-fever neutralizing antibodies in 53 SOT recipients vaccinated prior to transplantation (including 29 kidney recipients and 18 liver recipients). All but one (98%) had protective titers of antibodies after a median duration of 3 years (min.: 0.8, max.: 21) after transplantation. The median antibody level was 40 U/L (interquartile range: 40-80). For the 46 patients with a known or estimated date of vaccination, yellow-fever antibodies were still detectable after a median time of 13 years (range: 2-32 years) post-immunization. Our data suggest there is long-term persistence of antibodies to yellow fever in SOT recipients who have been vaccinated prior to transplantation. © Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.

  16. Delivering HIV Gagp24 to DCIR Induces Strong Antibody Responses In Vivo.

    Directory of Open Access Journals (Sweden)

    Anne-Laure Flamar

    Full Text Available Targeting dendritic cell-specific endocytic receptors using monoclonal antibodies fused to desired antigens is an approach widely used in vaccine development to enhance the poor immunogenicity of protein-based vaccines and to induce immune responses. Here, we engineered an anti-human DCIR recombinant antibody, which cross-reacts with the homologous cynomolgous macaque receptor and was fused via the heavy chain C-terminus to HIV Gagp24 protein (αDCIR.Gagp24. In vitro, αDCIR.Gagp24 expanded multifunctional antigen-specific memory CD4+ T cells recognizing multiple Gagp24 peptides from HIV-infected patient peripheral blood mononuclear cells. In non human primates, priming with αDCIR.Gagp24 without adjuvant elicited a strong anti-Gagp24 antibody response after the second immunization, while in the non-targeted HIV Gagp24 protein control groups the titers were weak. The presence of the double-stranded RNA poly(I:C adjuvant significantly enhanced the anti-Gagp24 antibody response in all the groups and reduced the discrimination between the different vaccine groups. The avidity of the anti-Gagp24 antibody responses was similar with either αDCIR.Gagp24 or Gagp24 immunization, but increased from medium to high avidity in both groups when poly(I:C was co-administered. This data provides a comparative analysis of DC-targeted and non-targeted proteins for their capacity to induce antigen-specific antibody responses in vivo. This study supports the further development of DCIR-based DC-targeting vaccines for protective durable antibody induction, especially in the absence of adjuvant.

  17. Immunization of cows with novel core glycolipid vaccine induces anti-endotoxin antibodies in bovine colostrum.

    Science.gov (United States)

    Cross, Alan S; Karreman, Hubert J; Zhang, Lei; Rosenberg, Zeil; Opal, Steven M; Lees, Andrew

    2014-10-21

    Translocation of gut-derived Gram-negative bacterial (GNB) lipopolysaccharide (LPS, or endotoxin) is a source of systemic inflammation that exacerbates HIV, cardiovascular and gastrointestinal diseases and malnutrition. The oral administration of bovine colostrum (BC) reduces endotoxemia in patients with impaired gut barrier function. Consequently, BC enriched in antibodies to LPS may ameliorate endotoxemia-related morbidities. We developed a detoxified J5 LPS/group B meningococcal outer membrane protein (J5dLPS/OMP) vaccine that induces antibodies against a highly conserved core region of LPS and protects against heterologous GNB infection. We now examine the ability of this vaccine to elicit anti-core endotoxin antibodies in BC. Two cohorts of pregnant cows were immunized with this vaccine in combination with FICA (Cohort 1) or Emulsigen-D (Cohort 2) adjuvants. Antibody responses to the J5 core LPS antigen were measured in both serum and colostrum and compared to antibody levels elicited by a commercially available veterinary vaccine (J5 Bacterin) comprised of heat-killed Escherichia coli O111, J5 mutant bacteria, from which the J5 LPS was purified. The J5dLPS/OMP vaccine induced high titers of serum IgG antibody to J5 LPS in all seven cows. Both IgG and to a lesser extent IgA anti-J5 LPS antibodies were generated in the colostrum. The J5dLPS/OMP vaccine was significantly more immunogenic in mice than was the J5 Bacterin. BC enriched in anti-J5 LPS antibody reduced circulating endotoxin levels in neutropenic rats, a model of "leaky gut". The J5dLPS/OMP vaccine elicits high titers of serum anti-endotoxin antibodies in cows that is passed to the colostrum. This BC enriched in anti-core LPS antibodies has the potential to reduce endotoxemia and ameliorate endotoxin-related systemic inflammation in patients with impaired gut barrier function. Since this vaccine is significantly more immunogenic than the J5 Bacterin vaccine, this J5dLPS/OMP vaccine might prove to be

  18. Anti-RAGE antibody attenuates isoflurane-induced cognitive dysfunction in aged rats.

    Science.gov (United States)

    Shi, Chengmei; Yi, Duan; Li, Zhengqian; Zhou, Yongde; Cao, Yiyun; Sun, Yan; Chui, Dehua; Guo, Xiangyang

    2017-03-30

    Several animal studies demonstrated that the volatile anesthetic isoflurane could influence the blood-brain barrier (BBB) integrity, which involved the cognitive impairment. Increasing evidence has also shown that the receptor for advanced glycation end-products (RAGE) played a major role in maintaining the integrity of BBB. The present study aimed to determine whether the RAGE-specific antibody protects against BBB disruption and cognitive impairment induced by isoflurane exposure in aged rats. 108 aged rats were randomly divided into four groups: (1) control group (Control); (2) 4h of 2% isoflurane exposure group (ISO); (3) RAGE antibody (20μL, 2.5μg/μL) treated+4h of 2% isoflurane exposure group (anti-RAGE+ISO); (4) RAGE antibody (20μL, 2.5μg/μL) treated group (anti-RAGE). The isoflurane anesthesia resulted in the upregulation of hippocampal RAGE expression, disruption of BBB integrity, neuroinflammation, and beta-amyloid (Aβ) accumulation in aged rats. In addition, significant cognitive deficits in the Morris water maze test was also observed. The antibody pretreatment resulted in significant improvements in BBB integrity. Furthermore, the expression of RAGE and proinflammatory mediators, as well as, Aβ accumulation were attenuated. Moreover, the antibody administration attenuated the isoflurane-induced cognitive impairment in aged rats. These results demonstrate that RAGE signaling is involved in BBB damage after isoflurane exposure. Thus, the RAGE antibody represents a novel therapeutic intervention to prevent isoflurane-induced cognitive impairment. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Irregular antibodies in no hemolytic autoimmune diseases are able to induce erythrophagocytosis.

    Science.gov (United States)

    López-Díaz, Paola Ester; Ruiz-Olivera, María Del Rocío; Hernández-Osorio, Luis Alberto; Vargas-Arzola, Jaime; Valle-Jiménez, Xareni; Aguilar-Ruiz, Sergio Roberto; Torres-Aguilar, Honorio

    2017-02-01

    Irregular antibodies are produced by alloimmunization because of pregnancies or blood transfusions. They are called "irregular" due to target erythrocyte antigens from "rare blood systems," those different from the ABO system. Irregular antibodies have been widely investigated in immunohematology since their presence in blood donors may lead to difficulties in blood typing and in blood cross-matching, or to induce hemolytic transfusion reactions. Nevertheless, their incidence and participation in the physiopathology of autoimmune diseases have not been thoroughly studied. In this work, we analyzed the presence and pro-hemolytic capabilities of irregular antibodies in patients with different autoimmune diseases lacking signs of hemolytic anemia, in comparison with healthy multiparous women. Five of 141 autoimmune patients (3.5 %) and two of 77 multiparous women (2.6 %) were positive. Although frequency was relatively low and similar in both populations, the targeted antigens were Kell (k, Kp b , Js b ) and Luth (Lu b ) in multiparous women, and the same plus Duffy (Fy a ), Kidd (Jk a ) and MNS (M, s) in autoimmune patients. Irregular antibodies from autoimmune patients did not induce complement-mediated hemolysis (intravascular), but they were able to induce macrophages-mediated phagocytosis (extravascular hemolysis) in vitro. It is the first approach exploring the presence of irregular antibodies associated with the loss of immune tolerance and demonstrating their hemolytic potential in autoimmune patients without hemolytic manifestations. The presence of irregular antibodies targeted to Duffy (Fya), Kidd (Jka) and MNS (M, s) antigens only in autoimmune patients suggests a loss of immune tolerance to these erythrocyte antigens.

  20. Papillomavirus pseudovirions packaged with the L2 gene induce cross-neutralizing antibodies

    Directory of Open Access Journals (Sweden)

    Duarte-Forero Diego F

    2010-03-01

    Full Text Available Abstract Background Current vaccines against HPVs are constituted of L1 protein self-assembled into virus-like particles (VLPs and they have been shown to protect against natural HPV16 and HPV18 infections and associated lesions. In addition, limited cross-protection has been observed against closely related types. Immunization with L2 protein in animal models has been shown to provide cross-protection against distant papillomavirus types, suggesting that the L2 protein contains cross-neutralizing epitopes. However, vaccination with L2 protein or L2 peptides does not induce high titers of anti-L2 antibodies. In order to develop a vaccine with the potential to protect against other high-risk HPV types, we have produced HPV58 pseudovirions encoding the HPV31 L2 protein and compared their capacity to induce cross-neutralizing antibodies with that of HPV L1 and HPV L1/L2 VLPs. Methods The titers of neutralizing antibodies against HPV16, HPV18, HPV31 and HPV58 induced in Balb/c mice were compared after immunization with L2-containing vaccines. Results Low titers of cross-neutralizing antibodies were detected in mice when immunized with L1/L2 VLPs, and the highest levels of cross-neutralizing antibodies were observed in mice immunized with HPV 58 L1/L2 pseudovirions encoding the HPV 31 L2 protein. Conclusions The results obtained indicate that high levels of cross-neutralizing antibodies are only observed after immunization with pseudovirions encoding the L2 protein. HPV pseudovirions thus represent a possible new strategy for the generation of a broad-spectrum vaccine to protect against high-risk HPVs and associated neoplasia.

  1. HER2 monoclonal antibodies that do not interfere with receptor heterodimerization-mediated signaling induce effective internalization and represent valuable components for rational antibody-drug conjugate design.

    Science.gov (United States)

    de Goeij, Bart E C G; Peipp, Matthias; de Haij, Simone; van den Brink, Edward N; Kellner, Christian; Riedl, Thilo; de Jong, Rob; Vink, Tom; Strumane, Kristin; Bleeker, Wim K; Parren, Paul W H I

    2014-01-01

    The human epidermal growth factor receptor (HER)2 provides an excellent target for selective delivery of cytotoxic drugs to tumor cells by antibody-drug conjugates (ADC) as has been clinically validated by ado-trastuzumab emtansine (Kadcyla(TM)). While selecting a suitable antibody for an ADC approach often takes specificity and efficient antibody-target complex internalization into account, the characteristics of the optimal antibody candidate remain poorly understood. We studied a large panel of human HER2 antibodies to identify the characteristics that make them most suitable for an ADC approach. As a model toxin, amenable to in vitro high-throughput screening, we employed Pseudomonas exotoxin A (ETA') fused to an anti-kappa light chain domain antibody. Cytotoxicity induced by HER2 antibodies, which were thus non-covalently linked to ETA', was assessed for high and low HER2 expressing tumor cell lines and correlated with internalization and downmodulation of HER2 antibody-target complexes. Our results demonstrate that HER2 antibodies that do not inhibit heterodimerization of HER2 with related ErbB receptors internalize more efficiently and show greater ETA'-mediated cytotoxicity than antibodies that do inhibit such heterodimerization. Moreover, stimulation with ErbB ligand significantly enhanced ADC-mediated tumor kill by antibodies that do not inhibit HER2 heterodimerization. This suggests that the formation of HER2/ErbB-heterodimers enhances ADC internalization and subsequent killing of tumor cells. Our study indicates that selecting HER2 ADCs that allow piggybacking of HER2 onto other ErbB receptors provides an attractive strategy for increasing ADC delivery and tumor cell killing capacity to both high and low HER2 expressing tumor cells.

  2. Fluorescent ampicillin analogues as multifunctional disguising agents against opsonization

    Science.gov (United States)

    Kotagiri, Nalinikanth; Sakon, Joshua; Han, Haewook; Zharov, Vladimir P.; Kim, Jin-Woo

    2016-06-01

    Cancer nanomedicines are opening new paradigms in cancer management and recent research points to how they can vastly improve imaging and therapy through multimodality and multifunctionality. However, challenges to achieving optimal efficacy are manifold starting from processing materials and evaluating their intended effectiveness on biological tissue, to developing new strategies aimed at improving transport of these materials through the biological milieu to the target tissue. Here, we report a fluorescent derivative of a beta-lactam antibiotic, ampicillin (termed iAmp) and its multifunctional physicobiochemical characteristics and potential as a biocompatible shielding agent and an effective dispersant. Carbon nanotubes (CNTs) were chosen to demonstrate the efficacy of iAmp. CNTs are known for their versatility and have been used extensively for cancer theranostics as photothermal and photoacoustic agents, but have limited solubility in water and biocompatibility. Traditional dispersants are associated with imaging artifacts and are not fully biocompatible. The chemical structure of iAmp is consistent with a deamination product of ampicillin. Although the four-membered lactam ring is intact, it does not retain the antibiotic properties. The iAmp is an effective dispersant and simultaneously serves as a fluorescent label for single-walled CNTs (SWNTs) with minimal photobleaching. The iAmp also enables bioconjugation of SWNTs to bio-ligands such as antibodies through functional carboxyl groups. Viability tests show that iAmp-coated SWNTs have minimal toxicity. Bio-stability tests under physiological conditions reveal that iAmp coating not only remains stable in a biologically relevant environment with high protein and salt concentrations, but also renders SWNTs transparent against nonspecific protein adsorption, also known as protein corona. Mammalian tissue culture studies with macrophages and opsonins validate that iAmp coating affords immunological resistance

  3. Recombinant influenza H7 hemagglutinins induce lower neutralizing antibody titers in mice than do seasonal hemagglutinins.

    Science.gov (United States)

    Blanchfield, Kristy; Kamal, Ram P; Tzeng, Wen-Pin; Music, Nedzad; Wilson, Jason R; Stevens, James; Lipatov, Aleksander S; Katz, Jacqueline M; York, Ian A

    2014-11-01

    Vaccines against avian influenza viruses often require high hemagglutinin (HA) doses or adjuvants to achieve serological titers associated with protection against disease. In particular, viruses of the H7 subtype frequently do not induce strong antibody responses following immunization. To evaluate whether poor immunogenicity of H7 viruses is an intrinsic property of the H7 hemagglutinin. We compared the immunogenicity, in naïve mice, of purified recombinant HA from two H7 viruses [A/Netherlands/219/2003(H7N7) and A/New York/107/2003(H7N2)] to that of HA from human pandemic [A/California/07/2009(H1N1pdm09)] and seasonal [A/Perth16/2009(H3N2)] viruses. After two intramuscular injections with purified hemagglutinin, mice produced antibodies to all HAs, but the response to the human virus HAs was greater than to H7 HAs. The difference was relatively minor when measured by ELISA, greater when measured by hemagglutination inhibition assays, and more marked still by microneutralization assays. H7 HAs induced little or no neutralizing antibody response in mice at either dose tested. Antibodies induced by H7 were of significantly lower avidity than for H3 or H1N1pdm09. We conclude that H7 HAs may be intrinsically less immunogenic than HA from seasonal human influenza viruses. © 2014 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

  4. Determining the Phagocytic Activity of Clinical Antibody Samples

    Science.gov (United States)

    McAndrew, Elizabeth G.; Dugast, Anne-Sophie; Licht, Anna F.; Eusebio, Justin R.; Alter, Galit; Ackerman, Margaret E.

    2011-01-01

    Antibody-driven phagocytosis is induced via the engagement of Fc receptors on professional phagocytes, and can contribute to both clearance as well as pathology of disease. While the properties of the variable domains of antibodies have long been considered critical to in vivo function, the ability of antibodies to recruit innate immune cells via their Fc domains has become increasingly appreciated as a major factor in their efficacy, both in the setting of recombinant monoclonal antibody therapy, as well as in the course of natural infection or vaccination1-3. Importantly, despite its nomenclature as a constant domain, the antibody Fc domain does not have constant function, and is strongly modulated by IgG subclass (IgG1-4) and glycosylation at Asparagine 2974-6. Thus, this method to study functional differences of antigen-specific antibodies in clinical samples will facilitate correlation of the phagocytic potential of antibodies to disease state, susceptibility to infection, progression, or clinical outcome. Furthermore, this effector function is particularly important in light of the documented ability of antibodies to enhance infection by providing pathogens access into host cells via Fc receptor-driven phagocytosis7. Additionally, there is some evidence that phagocytic uptake of immune complexes can impact the Th1/Th2 polarization of the immune response8. Here, we describe an assay designed to detect differences in antibody-induced phagocytosis, which may be caused by differential IgG subclass, glycan structure at Asn297, as well as the ability to form immune complexes of antigen-specific antibodies in a high-throughput fashion. To this end, 1 μm fluorescent beads are coated with antigen, then incubated with clinical antibody samples, generating fluorescent antigen specific immune complexes. These antibody-opsonized beads are then incubated with a monocytic cell line expressing multiple FcγRs, including both inhibitory and activating. Assay output can

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

    Science.gov (United States)

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

    2017-10-15

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

  6. Prevention of herpes simplex virus induced stromal keratitis by a glycoprotein B-specific monoclonal antibody.

    Directory of Open Access Journals (Sweden)

    Adalbert Krawczyk

    Full Text Available The increasing incidence of acyclovir (ACV and multidrug-resistant strains in patients with corneal HSV-1 infections leading to Herpetic Stromal Keratitis (HSK is a major health problem in industrialized countries and often results in blindness. To overcome this obstacle, we have previously developed an HSV-gB-specific monoclonal antibody (mAb 2c that proved to be highly protective in immunodeficient NOD/SCID-mice towards genital infections. In the present study, we examined the effectivity of mAb 2c in preventing the immunopathological disease HSK in the HSK BALB/c mouse model. Therefore, mice were inoculated with HSV-1 strain KOS on the scarified cornea to induce HSK and subsequently either systemically or topically treated with mAb 2c. Systemic treatment was performed by intravenous administration of mAb 2c 24 h prior to infection (pre-exposure prophylaxis or 24, 40, and 56 hours after infection (post-exposure immunotherapy. Topical treatment was performed by periodical inoculations (5 times per day of antibody-containing eye drops as control, starting at 24 h post infection. Systemic antibody treatment markedly reduced viral loads at the site of infection and completely protected mice from developing HSK. The administration of the antiviral antibody prior or post infection was equally effective. Topical treatment had no improving effect on the severity of HSK. In conclusion, our data demonstrate that mAb 2c proved to be an excellent drug for the treatment of corneal HSV-infections and for prevention of HSK and blindness. Moreover, the humanized counterpart (mAb hu2c was equally effective in protecting mice from HSV-induced HSK when compared to the parental mouse antibody. These results warrant the future development of this antibody as a novel approach for the treatment of corneal HSV-infections in humans.

  7. Celiac anti-type 2 transglutaminase antibodies induce phosphoproteome modification in intestinal epithelial Caco-2 cells.

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    Gaetana Paolella

    Full Text Available BACKGROUND: Celiac disease is an inflammatory condition of the small intestine that affects genetically predisposed individuals after dietary wheat gliadin ingestion. Type 2-transglutaminase (TG2 activity seems to be responsible for a strong autoimmune response in celiac disease, TG2 being the main autoantigen. Several studies support the concept that celiac anti-TG2 antibodies may contribute to disease pathogenesis. Our recent findings on the ability of anti-TG2 antibodies to induce a rapid intracellular mobilization of calcium ions, as well as extracellular signal-regulated kinase phosphorylation, suggest that they potentially act as signaling molecules. In line with this concept, we have investigated whether anti-TG2 antibodies can induce phosphoproteome modification in an intestinal epithelial cell line. METHODS AND PRINCIPAL FINDINGS: We studied phosphoproteome modification in Caco-2 cells treated with recombinant celiac anti-TG2 antibodies. We performed a two-dimensional electrophoresis followed by specific staining of phosphoproteins and mass spectrometry analysis of differentially phosphorylated proteins. Of 14 identified proteins (excluding two uncharacterized proteins, three were hypophosphorylated and nine were hyperphosphorylated. Bioinformatics analyses confirmed the presence of phosphorylation sites in all the identified proteins and highlighted their involvement in several fundamental biological processes, such as cell cycle progression, cell stress response, cytoskeletal organization and apoptosis. CONCLUSIONS: Identification of differentially phosphorylated proteins downstream of TG2-antibody stimulation suggests that in Caco-2 cells these antibodies perturb cell homeostasis by behaving as signaling molecules. We hypothesize that anti-TG2 autoantibodies may destabilize the integrity of the intestinal mucosa in celiac individuals, thus contributing to celiac disease establishment and progression. Since several proteins here

  8. A pilot study on an attenuated Chinese EIAV vaccine inducing broadly neutralizing antibodies.

    Science.gov (United States)

    Meng, Qinglai; Lin, Yuezhi; Ma, Jian; Ma, Yan; Zhao, Liping; Li, Shenwei; Liang, Hua; Zhou, Jianhua; Shen, Rongxian; Zhang, Xiaoyan; Shao, Yiming

    2011-08-01

    The attenuated Chinese equine infectious anemia virus (EIAV) vaccine has successfully protected millions of equine animals from EIA disease in China. In this pilot study, to determine whether this attenuated vaccine can induce broadly neutralizing antibodies, we immunized four horses with the attenuated Chinese vaccine strain EIAVFDDV and then observed the evolution of neutralizing antibodies against different EIAV strains. During the vaccination phase, all vaccinees rapidly developed high levels of neutralizing antibodies against the homologous vaccine strain (pLGFD3V), and 3 out of 4 horses showed a gradual increase in serum neutralizing activity against two relatively heterologous virulent variants of the challenge strain (pLGFD3Mu12V and DLV34). After challenge, the three horses that had developed high levels of neutralizing antibodies against pLGFD3Mu12V and DLV34 did not show signs of infection, which was demonstrated by immune suppression, while the one horse producing serum that could only neutralize pLGFD3V developed a febrile episode during the 8-month observation period. To assess whether the broadly neutralizing activity is associated with immune protection, sera drawn on the day of challenge from these four vaccinees and an additional four EIAVFDDV-vaccinated horses were analyzed for neutralizing antibodies against pLGFD3V, pLGFD3Mu12V and DLV34. Although there was no significant correlation between protection from infection and serum neutralizing activity against any of these three viral strains, protection from infection was observed to correlate better with serum neutralizing activity against the two heterologous virulent strains than against the homologous vaccine strain. These data indicate that EIAVFDDV induced broadly neutralizing antibodies, which might confer enhanced protection of vaccinees from infection by the challenge virus.

  9. Modeling maternal fetal RSV F vaccine induced antibody transfer in guinea pigs.

    Science.gov (United States)

    Glenn, Gregory M; Fries, Louis F; Smith, Gale; Kpamegan, Eloi; Lu, Hanxin; Guebre-Xabier, Mimi; Hickman, Somia P; Flyer, David

    2015-11-25

    Protection of newborns and young infants against RSV disease via maternal immunization mediated by transplacental transfer of antibodies is under evaluation in third-trimester pregnant women with the RSV recombinant F nanoparticle vaccine (RSV F vaccine). Since the hemichorial placental architecture in guinea pigs and humans is similar, the guinea pig model was employed to assess RSV F vaccine immunogenicity in pregnant sows and to compare RSV-specific maternal antibody levels in their pups. Thirty (30) presumptive pregnant guinea pigs were immunized on gestational day 25 and 46 with placebo (PBS), 30μg RSV F, or 30μg RSV F+400μg aluminum phosphate. Sera at delivery/birth (sows/pups) and 15 and 30 days post-partum (pups) were analyzed for the presence of anti-F IgG, palivizumab-competitive antibody (PCA) and RSV/A microneutralization (MN). The rates of pregnancy and stillbirth were similar between controls and vaccinees. The vaccine induced high levels of anti-F IgG, PCA and MN in sows, with the highest levels observed in adjuvanted vaccinees. Placental transfer to pups was proportional to the maternal antibody levels, with concentration effects observed for all immune measures. The RSV F vaccine was safe and immunogenic in pregnant guinea pigs and supported robust transplacental antibody transfer to their pups. Relative concentration of antibodies in the pups was observed even in the presence of high levels of maternal antibody. Guinea pigs may be an important safety and immunogenicity model for preclinical assessment of candidate vaccines for maternal immunization. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Long-Term Antibody and Immune Memory Response Induced by Pulmonary Delivery of the Influenza Iscomatrix Vaccine

    OpenAIRE

    Vujanic, Ana; Snibson, Kenneth J.; Wee, Janet L. K.; Edwards, Stirling J.; Pearse, Martin J.; Scheerlinck, Jean-Pierre Y.; Sutton, Philip

    2012-01-01

    Pulmonary delivery of an influenza Iscomatrix adjuvant vaccine induces a strong systemic and mucosal antibody response. Since an influenza vaccine needs to induce immunological memory that lasts at least 1 year for utility in humans, we examined the longevity of the immune response induced by such a pulmonary vaccination, with and without antigen challenge. Sheep were vaccinated in the deep lung with an influenza Iscomatrix vaccine, and serum and lung antibody levels were quantified for up to...

  11. An antibody blocking activin type II receptors induces strong skeletal muscle hypertrophy and protects from atrophy.

    Science.gov (United States)

    Lach-Trifilieff, Estelle; Minetti, Giulia C; Sheppard, KellyAnn; Ibebunjo, Chikwendu; Feige, Jerome N; Hartmann, Steffen; Brachat, Sophie; Rivet, Helene; Koelbing, Claudia; Morvan, Frederic; Hatakeyama, Shinji; Glass, David J

    2014-02-01

    The myostatin/activin type II receptor (ActRII) pathway has been identified to be critical in regulating skeletal muscle size. Several other ligands, including GDF11 and the activins, signal through this pathway, suggesting that the ActRII receptors are major regulatory nodes in the regulation of muscle mass. We have developed a novel, human anti-ActRII antibody (bimagrumab, or BYM338) to prevent binding of ligands to the receptors and thus inhibit downstream signaling. BYM338 enhances differentiation of primary human skeletal myoblasts and counteracts the inhibition of differentiation induced by myostatin or activin A. BYM338 prevents myostatin- or activin A-induced atrophy through inhibition of Smad2/3 phosphorylation, thus sparing the myosin heavy chain from degradation. BYM338 dramatically increases skeletal muscle mass in mice, beyond sole inhibition of myostatin, detected by comparing the antibody with a myostatin inhibitor. A mouse version of the antibody induces enhanced muscle hypertrophy in myostatin mutant mice, further confirming a beneficial effect on muscle growth beyond myostatin inhibition alone through blockade of ActRII ligands. BYM338 protects muscles from glucocorticoid-induced atrophy and weakness via prevention of muscle and tetanic force losses. These data highlight the compelling therapeutic potential of BYM338 for the treatment of skeletal muscle atrophy and weakness in multiple settings.

  12. Antibodies with higher bactericidal activity induced by a Neisseria gonorrhoeae Rmp deletion mutant strain.

    Directory of Open Access Journals (Sweden)

    Guocai Li

    Full Text Available Neisseria gonorrhoeae (N. gonorrhoeae outer membrane protein reduction modifiable protein (Rmp has strong immunogenicity. However, anti-Rmp antibodies block rather than preserve the antibacterial effects of protective antibodies, which hampers the development of vaccines for gonococcal infections. We herein constructed an Rmp deletion mutant strain of N. gonorrhoeae by gene homologous recombination. The 261-460 nucleotide residues of Rmp gene amplified from N. gonorrhoeae WHO-A strain were replaced with a kanamycin-resistant Kan gene amplified from pET-28a. The resultant hybridized DNA was transformed into N. gonorrhoeae WHO-A strain. PCR was used to screen the colonies in which wild-type Rmp gene was replaced with a mutant gene fragment. Western blotting revealed that the Rmp deletion mutant strain did not express Rmp protein. Rmp deletion did not alter the morphological and Gram staining properties of the mutant strain that grew slightly more slowly than the wild-type one. Rmp gene mutated stably throughout 25 generations of passage. Antibody-mediated complement-dependent cytotoxicity assay indicated that the antibodies induced by the mutant strain had evidently higher bactericidal activities than those induced by the wild-type strain. Further modification of the Rmp deletion mutant strain is still required in the development of novel live attenuated vaccines for gonorrhea by Opa genes deletion or screening of phenotypic variant strains that do not express Opa proteins.

  13. Human vaccination against Plasmodium vivax Duffy-binding protein induces strain-transcending antibodies

    OpenAIRE

    Payne, Ruth O.; Silk, Sarah E.; Elias, Sean C.; Milne, Kathryn H.; Rawlinson, Thomas A.; Llewellyn, David; Shakri, A. Rushdi; Jin, Jing; Labb?, Genevi?ve M.; Edwards, Nick J.; Poulton, Ian D.; Roberts, Rachel; Farid, Ryan; J?rgensen, Thomas; Alanine, Daniel G.W.

    2017-01-01

    BACKGROUND: Plasmodium vivax is the most widespread human malaria geographically; however, no effective vaccine exists. Red blood cell invasion by the P. vivax merozoite depends on an interaction between the Duffy antigen receptor for chemokines (DARC) and region II of the parasite's Duffy-binding protein (PvDBP_RII). Naturally acquired binding-inhibitory antibodies against this interaction associate with clinical immunity, but it is unknown whether these responses can be induced by human vac...

  14. Development of a peptide conjugate vaccine for inducing therapeutic anti-IgE antibodies.

    Science.gov (United States)

    Licari, Amelia; Castagnoli, Riccardo; De Sando, Elisabetta; Marseglia, Gian Luigi

    2017-04-01

    Given the multifaceted effector functions of IgE in immediate hypersensitivity, late-phase reactions, regulation of IgE receptor expression and immune modulation, IgE antibodies have long represented an attractive target for therapeutic agents in asthma and other allergic diseases. Effective pharmacologic blockade of the binding of IgE to its receptors has become one of most innovative therapeutic strategies in the field of allergic diseases in the last 10 years. Areas covered: The latest strategies targeting IgE include the development of a therapeutic vaccine, able to trigger our own immune systems to produce therapeutic anti-IgE antibodies, potentially providing a further step forward in the treatment of allergic diseases. The aim of this review is to discuss the discovery strategy, preclinical and early clinical development of a peptide conjugate vaccine for inducing therapeutic anti-IgE antibodies. Expert opinion: Outside the area of development of humanized anti-IgE monoclonal antibodies, the research field of therapeutic IgE-targeted vaccines holds potential benefits for the treatment of allergic diseases. However, most of the experimental observations in animal models have not yet been translated into new treatments and evidence of human efficacy and safety of this new therapeutic strategy are still lacking.

  15. Native Mass Spectrometry, Ion mobility, and Collision-Induced Unfolding Categorize Malaria Antigen/Antibody Binding

    Science.gov (United States)

    Huang, Yining; Salinas, Nichole D.; Chen, Edwin; Tolia, Niraj H.; Gross, Michael L.

    2017-09-01

    Plasmodium vivax Duffy Binding Protein (PvDBP) is a promising vaccine candidate for P. vivax malaria. Recently, we reported the epitopes on PvDBP region II (PvDBP-II) for three inhibitory monoclonal antibodies (2D10, 2H2, and 2C6). In this communication, we describe the combination of native mass spectrometry and ion mobility (IM) with collision induced unfolding (CIU) to study the conformation and stabilities of three malarial antigen-antibody complexes. These complexes, when collisionally activated, undergo conformational changes that depend on the location of the epitope. CIU patterns for PvDBP-II in complex with antibody 2D10 and 2H2 are highly similar, indicating comparable binding topology and stability. A different CIU fingerprint is observed for PvDBP-II/2C6, indicating that 2C6 binds to PvDBP-II on an epitope different from 2D10 and 2H2. This work supports the use of CIU as a means of classifying antigen-antibody complexes by their epitope maps in a high throughput screening workflow. [Figure not available: see fulltext.

  16. Anti-TNF-α antibody alleviates insulin resistance in rats with sepsis-induced stress hyperglycemia.

    Science.gov (United States)

    Qu, W; Han, C; Li, M; Zhang, J; Jiang, Z

    2017-10-13

    To explore the effects and mechanisms of anti-tumor necrosis factor-α (TNF-α) antibody on insulin resistance (IR) in rats with sepsis-induced stress hyperglycemia. The sepsis-induced stress hyperglycemic rat model was constructed by cecal ligation and puncture combined with the intraperitoneal injection of lipopolysaccharide. The rats were randomly divided into six groups: normal control (NC) group, surgical rats (Cntl) group, high-dose anti-TNF-α antibody therapy (TNF, 6 mg/kg) group, low-dose anti-TNF-α antibody therapy (Tnf, 3 mg/kg) group, insulin therapy (INS) group, and INS + Tnf group. The blood glucose and serum insulin concentrations were detected, followed by analysis of intraperitoneal glucose tolerance test (IPGTT) and hyperinsulinemic-euglycemic clamp. Finally, the expression levels of phospho-Akt (p-Akt), Akt, p-mTOR, mTOR, nuclear factor-κB (NFκB), I kappa beta kinase (IKKβ), and suppressor of cytokine signaling (SOCS-3) were detected by western blotting. There was no significant difference in blood glucose concentrations among these groups, while the serum insulin concentration in TNF and Tnf groups was lower than that in the Cntl group at postoperative 6 h (P TNF group than that in the Cntl group (P Tnf and TNF groups (P TNF-α antibody could reduce IR by inhibiting AKt/mTOR signaling pathway and the expression levels of NFκB, IKKβ, and SOCS-3 in rats with sepsis-induced stress hyperglycemia.

  17. Squalene-containing licensed adjuvants enhance strain-specific antibody responses against the influenza hemagglutinin and induce subtype-specific antibodies against the neuraminidase.

    Science.gov (United States)

    Schmidt, Rebecca; Holznagel, Edgar; Neumann, Britta; Alex, Nina; Sawatsky, Bevan; Enkirch, Theresa; Pfeffermann, Kristin; Kruip, Carina; von Messling, Veronika; Wagner, Ralf

    2016-10-17

    While seasonal influenza vaccines are usually non-adjuvanted, H1N1pdm09 vaccines were formulated with different squalene-containing adjuvants, to enable the reduction of antigen content thus increasing the number of doses available. To comparatively assess the effects of these adjuvants on antibody responses against matched and mismatched strains, and to correlate antibody levels with protection from disease, ferrets were immunized with 2μg of commercial H1N1pdm09 vaccine antigen alone or formulated with different licensed adjuvants. The use of squalene-containing adjuvants increased neutralizing antibody responses around 100-fold, and resulted in a significantly reduced viral load after challenge with a matched strain. While all animals mounted strong total antibody responses against the homologous H1N1 hemagglutinin (HA) protein, which correlated with the respective neutralizing antibody titers, no reactivity with the divergent H3, H5, H7, and H9 proteins were detected. Only the adjuvanted vaccines also induced antibodies against the neuraminidase (NA) protein, which were able to also recognize NA proteins from other N1 carrying strains. These findings not only support the use of squalene-containing adjuvants in dose-sparing strategies but also support speculations that the induction of NA-specific responses associated with the use of these adjuvants may confer partial protection to heterologous strains carrying the same NA subtype. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Vancomycin-induced Immune Thrombocytopenia Proven by the Detection of Vancomycin-dependent Anti-platelet Antibody with Flow Cytometry

    OpenAIRE

    Yamanouchi, Jun; Hato, Takaaki; Shiraishi, Sanshiro; Takeuchi, Kazuto; Yakushijin, Yoshihiro; Yasukawa, Masaki

    2016-01-01

    Vancomycin-induced thrombocytopenia is a rare adverse reaction that may be overlooked because no specific diagnostic test is currently available. We herein report a patient with vancomycin-induced immune thrombocytopenia who was diagnosed by the detection of vancomycin-dependent anti-platelet antibody with flow cytometry. An IgG antibody in the patient's serum reacted with platelets only in the presence of vancomycin. Severe thrombocytopenia gave rise to life-threatening gastrointestinal blee...

  19. Drug-induced hepatitis superimposed on the presence of anti-SLA antibody: a case report

    Directory of Open Access Journals (Sweden)

    Etxagibel Aitziber

    2008-01-01

    Full Text Available Abstract Introduction Autoimmune hepatitis is a necroinflammatory disorder of unknown etiology characterized by the presence of circulating antibodies, hypergammaglobulinemia, and response to immunosuppression. It has the histological features of chronic hepatitis. The onset is usually insidious, but in some patients the presentation may be acute and occasionally severe. Certain drugs can induce chronic hepatitis mimicking autoimmune hepatitis. Different autoantibodies have been associated with this process but they are not detectable after drug withdrawal and clinical resolution. Case presentation We describe a case of drug-induced acute hepatitis associated with antinuclear, antisoluble liver-pancreas and anti-smooth muscle autoantibodies in a 66-year-old woman. Abnormal clinical and biochemical parameters resolved after drug withdrawal, but six months later anti-soluble liver-pancreas antibodies remained positive and liver biopsy showed chronic hepatitis and septal fibrosis. Furthermore, our patient has a HLA genotype associated with autoimmune hepatitis. Conclusion Patient follow-up will disclose whether our patient suffers from an autoimmune disease and if the presence of anti-soluble liver antigens could precede the development of an autoimmune hepatitis, as the presence of antimitochondrial antibodies can precede primary biliary cirrhosis.

  20. Adjuvants and immunization strategies to induce influenza virus hemagglutinin stalk antibodies.

    Directory of Open Access Journals (Sweden)

    Peter H Goff

    Full Text Available The global population remains vulnerable in the face of the next pandemic influenza virus outbreak, and reformulated vaccinations are administered annually to manage seasonal epidemics. Therefore, development of a new generation of vaccines is needed to generate broad and persistent immunity to influenza viruses. Here, we describe three adjuvants that enhance the induction of stalk-directed antibodies against heterologous and heterosubtypic influenza viruses when administered with chimeric HA proteins. Addavax, an MF59-like nanoemulsion, poly(I:C, and an RNA hairpin derived from Sendai virus (SeV Cantell were efficacious intramuscularly. The SeV RNA and poly(I:C also proved to be effective respiratory mucosal adjuvants. Although the quantity and quality of antibodies induced by the adjuvants varied, immunized mice demonstrated comparable levels of protection against challenge with influenza A viruses on the basis of HA stalk reactivity. Finally, we present that intranasally, but not intramuscularly, administered chimeric HA proteins induce mucosal IgA antibodies directed at the HA stalk.

  1. Interactions of opsonized immune complexes with whole blood cells: binding to erythrocytes restricts complex uptake by leucocyte populations

    DEFF Research Database (Denmark)

    Nielsen, C H; Svehag, S E; Marquart, H V

    1994-01-01

    The binding of opsonized, fluorescein-labelled bovine serum albumin (BSA)/rabbit anti-BSA complexes (IC) to washed human whole blood cells and isolated leucocytes in the presence of autologous serum was investigated by flow cytometry. In the presence of erythrocytes (E), the IC-binding to granulo......The binding of opsonized, fluorescein-labelled bovine serum albumin (BSA)/rabbit anti-BSA complexes (IC) to washed human whole blood cells and isolated leucocytes in the presence of autologous serum was investigated by flow cytometry. In the presence of erythrocytes (E), the IC...

  2. Enhanced opsonisation of Rhesus D-positive human red blood cells by recombinant polymeric immunoglobulin G anti-G antibodies.

    Science.gov (United States)

    Díaz-Solano, Dylana; Fuenmayor, Jaheli; Montaño, Ramon F

    2018-02-01

    Anti-RhD antibodies (anti-D) are important in the prophylaxis of haemolytic disease of the foetus and newborn (HDFN) due to RhD incompatibility. Current preparations of anti-D are sourced from hyperimmune human plasma, so its production carries a risk of disease and is dependent on donor availability. Despite the efforts to develop a monoclonal preparation with similar prophylactic properties to the plasma-derived anti-D, no such antibody is yet available. Here we studied the agglutinating, opsonic and haemolytic activities of two recombinant polymeric immunoglobulins (Ig) against the G antigen of the Rh complex. Recombinant polymeric anti-G IgG1 (IgG1μtp) and IgG3 (IgG3μtp) were produced in vitro, purified by protein G-affinity chromatography, and analysed by gel electrophoresis. Their agglutinating, opsonic and haemolytic activities were evaluated using haemagglutination, erythrophagocytosis, and complement activation assays. The recombinant IgG1μtp and IgG3μtp anti-G antibodies ranged from 150,000 to 1,000,000 Da in molecular weight, indicating the formation of polymeric IgG. No complement activation or haemolytic activity was detected upon incubation of RhD-positive red-blood cells with the polymeric anti-G IgG. Both polymers were better opsonins than a prophylactic preparation of plasma-derived anti-D. The enhanced opsonic properties of the polymeric anti-G IgG1μtp and IgG3μtp could allow them to mediate the clearance of RhD-positive red blood cells from circulation more efficiently than natural or other synthetic prophylactic anti-D options. Their inability to induce complement-mediated haemolysis would be prophylactically convenient and is comparable in vitro to that of the available plasma-derived polyclonal anti-D preparations. The described properties suggest that polymeric antibodies like these (but with anti-D specificity) may be testable candidates for prophylaxis of HDFN caused by anti-D.

  3. Immunological mimicry of PrPC-PrPSc interactions: antibody-induced PrP misfolding.

    Science.gov (United States)

    Li, Li; Guest, Will; Huang, Alan; Plotkin, Steven S; Cashman, Neil R

    2009-08-01

    Prion diseases are associated with the conversion of cellular prion protein (PrP(C)) to an abnormal protease-resistant conformational isoform (PrP(Sc)) by template-directed conversion. The interaction between PrP(C) and PrP(Sc) is mediated by specific sites which have been mapped to six putative 'binding and conversion domains' (PrP-BCD) through peptide and antibody competition studies. Monoclonal antibodies (mAbs) directed against the bityrosine motif Tyr-Tyr-Arg (YYR) specifically recognize PrP(Sc) and other misfolded PrP species. Here, we report that select bead-bound PrP-BCD mAbs induce exposure of bityrosine epitopes on mouse brain PrP. By competition immunoprecipitation, we show that PrP-BCD mAb-induced bityrosine exposure occurs at alpha-helices 1 and 3. However, PrP-BCD mAb-induced PrP(C) misfolding is not accompanied by beta-sheet dissociation, a key event in PrP(C) conversion to PrP(Sc), and is not associated with acquisition of protease resistance, or the capacity to recruit additional molecules of PrP. Our data suggest that mAb mimics of the physical interaction of PrP(C) with PrP(Sc) can induce unfolding of specific PrP domains, but that subsequent processes (including the energetically unfavorable beta-sheet dissociation) effect isoform conversion in prion disease.

  4. Antibody against the insulin receptor causes disappearance of insulin receptors in 3T3-L1 cells: a possible explanation of antibody-induced insulin resistance.

    OpenAIRE

    Grunfeld, C

    1984-01-01

    The effect of a rabbit antibody induced against the rat insulin receptor (RAR) was tested using cultured 3T3-L1 fat cells. As previously seen with antibodies against the insulin receptor from patients with the type B syndrome of insulin resistance and acanthosis nigricans, RAR acutely mimicked the action of insulin by stimulating deoxyglucose uptake. After prolonged exposure of 3T3-L1 cells to RAR, insulinomimetic activity was lost and the cells became resistant to the action of insulin. This...

  5. A noncognate interaction with anti-receptor antibody-activated helper T cells induces small resting murine B cells to proliferate and to secrete antibody

    DEFF Research Database (Denmark)

    Owens, T

    1988-01-01

    on resting B cells (even in the presence of intact F23.1 antibody), but could induce antibody secretion by anti-Ig-preactivated B cells. Both F23.1+ clones (E9.D4 and 4.35F2) and one F23.1- clone (D2.2) could synergize with supernatants from activated E9.D4 T cells to induce B cell activation. F(ab')2......Culture of small resting allogeneic B cells (of an irrelevant haplotype) with two clones of T helper (Th) cells that were activated by the F23.1 anti-T cell receptor antibody led to the activation of B cells to proliferate and to secrete antibody. Th cell supernatants by themselves had no effect...... fragments of F23.1 induced E9.D4 to activate B cells as efficiently as intact F23.1 and B cell populations that had been incubated with F23.1 were not activated when cultured with E9.D4, although T cells recognized cell-presented F23.1 and were weakly activated. Reduction of the density of F23.1 adsorbed...

  6. Ability of vaccine strain induced antibodies to neutralize field isolates of caliciviruses from Swedish cats.

    Science.gov (United States)

    Wensman, Jonas Johansson; Samman, Ayman; Lindhe, Anna; Thibault, Jean-Christophe; Berndtsson, Louise Treiberg; Hosie, Margaret J

    2015-12-12

    Feline calicivirus (FCV) is a common cause of upper respiratory tract disease in cats worldwide. Its characteristically high mutation rate leads to escape from the humoral immune response induced by natural infection and/or vaccination and consequently vaccines are not always effective against field isolates. Thus, there is a need to continuously investigate the ability of FCV vaccine strain-induced antibodies to neutralize field isolates. Seventy-eight field isolates of FCV isolated during the years 2008-2012 from Swedish cats displaying clinical signs of upper respiratory tract disease were examined in this study. The field isolates were tested for cross-neutralization using a panel of eight anti-sera raised in four pairs of cats following infection with four vaccine strains (F9, 255, G1 and 431). The anti-sera raised against F9 and 255 neutralised 20.5 and 11.5 %, and 47.4 and 64.1 % of field isolates tested, respectively. The anti-sera against the more recently introduced vaccine strains G1 and 431 neutralized 33.3 and 55.1 % (strain G1) or 69.2 and 89.7 % (strain 431) of the field isolates with titres ≥5. [corrected]. Dual vaccine strains displayed a higher cross-neutralization. This study confirms previous observations that more recently introduced vaccine strains induce antibodies with a higher neutralizing capacity compared to vaccine strains that have been used extensively over a long period of time. This study also suggests that dual FCV vaccine strains might neutralize more field isolates compared to single vaccine strains. Vaccine strains should ideally be selected based on updated knowledge on the antigenic properties of field isolates in the local setting, and there is thus a need for continuously studying the evolution of FCV together with the neutralizing capacity of vaccine strain induced antibodies against field isolates at a national and/or regional level.

  7. HIV-1 vaccine-induced C1 and V2 Env-specific antibodies synergize for increased antiviral activities.

    Science.gov (United States)

    Pollara, Justin; Bonsignori, Mattia; Moody, M Anthony; Liu, Pinghuang; Alam, S Munir; Hwang, Kwan-Ki; Gurley, Thaddeus C; Kozink, Daniel M; Armand, Lawrence C; Marshall, Dawn J; Whitesides, John F; Kaewkungwal, Jaranit; Nitayaphan, Sorachai; Pitisuttithum, Punnee; Rerks-Ngarm, Supachai; Robb, Merlin L; O'Connell, Robert J; Kim, Jerome H; Michael, Nelson L; Montefiori, David C; Tomaras, Georgia D; Liao, Hua-Xin; Haynes, Barton F; Ferrari, Guido

    2014-07-01

    The RV144 ALVAC/AIDSVax HIV-1 vaccine clinical trial showed an estimated vaccine efficacy of 31.2%. Viral genetic analysis identified a vaccine-induced site of immune pressure in the HIV-1 envelope (Env) variable region 2 (V2) focused on residue 169, which is included in the epitope recognized by vaccinee-derived V2 monoclonal antibodies. The ALVAC/AIDSVax vaccine induced antibody-dependent cellular cytotoxicity (ADCC) against the Env V2 and constant 1 (C1) regions. In the presence of low IgA Env antibody levels, plasma levels of ADCC activity correlated with lower risk of infection. In this study, we demonstrate that C1 and V2 monoclonal antibodies isolated from RV144 vaccinees synergized for neutralization, infectious virus capture, and ADCC. Importantly, synergy increased the HIV-1 ADCC activity of V2 monoclonal antibody CH58 at concentrations similar to that observed in plasma of RV144 vaccinees. These findings raise the hypothesis that synergy among vaccine-induced antibodies with different epitope specificities contributes to HIV-1 antiviral antibody responses and is important to induce for reduction in the risk of HIV-1 transmission. Importance: The Thai RV144 ALVAC/AIDSVax prime-boost vaccine efficacy trial represents the only example of HIV-1 vaccine efficacy in humans to date. Studies aimed at identifying immune correlates involved in the modest vaccine-mediated protection identified HIV-1 envelope (Env) variable region 2-binding antibodies as inversely correlated with infection risk, and genetic analysis identified a site of immune pressure within the region recognized by these antibodies. Despite this evidence, the antiviral mechanisms by which variable region 2-specific antibodies may have contributed to lower rates of infection remain unclear. In this study, we demonstrate that vaccine-induced HIV-1 envelope variable region 2 and constant region 1 antibodies synergize for recognition of virus-infected cells, infectious virion capture, virus

  8. Both Neutralizing and Non-Neutralizing Human H7N9 Influenza Vaccine-Induced Monoclonal Antibodies Confer Protection.

    Science.gov (United States)

    Henry Dunand, Carole J; Leon, Paul E; Huang, Min; Choi, Angela; Chromikova, Veronika; Ho, Irvin Y; Tan, Gene S; Cruz, John; Hirsh, Ariana; Zheng, Nai-Ying; Mullarkey, Caitlin E; Ennis, Francis A; Terajima, Masanori; Treanor, John J; Topham, David J; Subbarao, Kanta; Palese, Peter; Krammer, Florian; Wilson, Patrick C

    2016-06-08

    Pathogenic H7N9 avian influenza viruses continue to represent a public health concern, and several candidate vaccines are currently being developed. It is vital to assess if protective antibodies are induced following vaccination and to characterize the diversity of epitopes targeted. Here we characterized the binding and functional properties of twelve H7-reactive human antibodies induced by a candidate A/Anhui/1/2013 (H7N9) vaccine. Both neutralizing and non-neutralizing antibodies protected mice in vivo during passive transfer challenge experiments. Mapping the H7 hemagglutinin antigenic sites by generating escape mutant variants against the neutralizing antibodies identified unique epitopes on the head and stalk domains. Further, the broadly cross-reactive non-neutralizing antibodies generated in this study were protective through Fc-mediated effector cell recruitment. These findings reveal important properties of vaccine-induced antibodies and provide a better understanding of the human monoclonal antibody response to influenza in the context of vaccines. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Inducing cross-clade neutralizing antibodies against HIV-1 by immunofocusing.

    Directory of Open Access Journals (Sweden)

    Michael Humbert

    Full Text Available Although vaccines are important in preventing viral infections by inducing neutralizing antibodies (nAbs, HIV-1 has proven to be a difficult target and escapes humoral immunity through various mechanisms. We sought to test whether HIV-1 Env mimics may serve as immunogens.Using random peptide phage display libraries, we identified the epitopes recognized by polyclonal antibodies of a rhesus monkey that had developed high-titer, broadly reactive nAbs after infection with a simian-human immunodeficiency virus (SHIV encoding env of a recently transmitted HIV-1 clade C (HIV-C. Phage peptide inserts were analyzed for conformational and linear homology using computational analysis; some peptides mimicked various domains of the original HIV-C Env, such as conformational V3 loop epitopes and the conserved linear region of the gp120 C-terminus. Next, we devised a novel prime/boost strategy to test the immunogenicity of such phage-displayed peptides and primed mice only once with HIV-C gp160 DNA followed by boosting with mixtures of recombinant phages.This strategy, which was designed to focus the immune system on a few Env epitopes (immunofocusing, not only induced HIV-C gp160 binding antibodies and cross-clade nAbs, but also linked a conserved HIV Env region for the first time to the induction of nAbs: the C-terminus of gp120. The identification of conserved antigen mimics may lead to novel immunogens capable of inducing broadly reactive nAbs.

  10. A Homology Model Reveals Novel Structural Features and an Immunodominant Surface Loop/Opsonic Target in the Treponema pallidum BamA Ortholog TP_0326.

    Science.gov (United States)

    Luthra, Amit; Anand, Arvind; Hawley, Kelly L; LeDoyt, Morgan; La Vake, Carson J; Caimano, Melissa J; Cruz, Adriana R; Salazar, Juan C; Radolf, Justin D

    2015-06-01

    We recently demonstrated that TP_0326 is a bona fide rare outer membrane protein (OMP) in Treponema pallidum and that it possesses characteristic BamA bipartite topology. Herein, we used immunofluorescence analysis (IFA) to show that only the β-barrel domain of TP_0326 contains surface-exposed epitopes in intact T. pallidum. Using the solved structure of Neisseria gonorrhoeae BamA, we generated a homology model of full-length TP_0326. Although the model predicts a typical BamA fold, the β-barrel harbors features not described in other BamAs. Structural modeling predicted that a dome comprised of three large extracellular loops, loop 4 (L4), L6, and L7, covers the barrel's extracellular opening. L4, the dome's major surface-accessible loop, contains mainly charged residues, while L7 is largely neutral and contains a polyserine tract in a two-tiered conformation. L6 projects into the β-barrel but lacks the VRGF/Y motif that anchors L6 within other BamAs. IFA and opsonophagocytosis assay revealed that L4 is surface exposed and an opsonic target. Consistent with B cell epitope predictions, immunoblotting and enzyme-linked immunosorbent assay (ELISA) confirmed that L4 is an immunodominant loop in T. pallidum-infected rabbits and humans with secondary syphilis. Antibody capture experiments using Escherichia coli expressing OM-localized TP_0326 as a T. pallidum surrogate further established the surface accessibility of L4. Lastly, we found that a naturally occurring substitution (Leu(593) → Gln(593)) in the L4 sequences of T. pallidum strains affects antibody binding in sera from syphilitic patients. Ours is the first study to employ a "structure-to-pathogenesis" approach to map the surface topology of a T. pallidum OMP within the context of syphilitic infection. Previously, we reported that TP_0326 is a bona fide rare outer membrane protein (OMP) in Treponema pallidum and that it possesses the bipartite topology characteristic of a BamA ortholog. Using a homology

  11. Cytotoxicity of human lymphocytes induced by rabbit antibodies to chicken erythrocytes

    Science.gov (United States)

    Larsson, Å.; Perlmann, P.; Natvig, J. B.

    1973-01-01

    Normal IgG preparations of human, rabbit or guinea-pig origin (IgG2) were tested for their capacity to inhibit the cytotoxicity of purified human lymphocytes, as induced by rabbit IgG antibodies to chicken erythrocytes. All IgGs were found to be about equally efficient inhibitors. Human F(ab′)2 used for control, gave no inhibition. Human myeloma proteins of subclasses IgG1, IgG2 and IgG3, were about equally efficient inhibitors. In contrast, the inhibitory action of myeloma proteins belonging to subclass IgG4 was weak and more irregular. In this assay system, a large excess (∼ 106 ×) of normal IgG over antibodies had to be added in order to achieve ≥50 per cent inhibition. Heating of the inhibitors to 63° for 30 minutes did not significantly enhance their inhibitory capacity. For comparison, the same human IgG preparations and myeloma proteins were also tested for their capacity to inhibit phagocytosis by human blood monocytes of chicken erythrocytes sensitized with rabbit IgG antibody. As was to be expected in this system, only HGG, IgG1 and IgG3 caused inhibition whereas F(ab′)2, IgG2 and IgG4 were completely negative. PMID:4127729

  12. 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

    -neutralizing antibodies in BALB/c mice, demonstrating its efficacy. In an in vivo ADE model, mE1E2bv VLP-induced antibodies lacked discernible ADE potential, compared to the cross-reactive monoclonal antibody 4G2, as evidenced by significant reduction in the levels of IL-6 and TNF-α, suggesting inherent safety. The results obtained with these bivalent mVLPs suggest the feasibility of incorporating the E proteins of DENV-3 and DENV-4 to create a tetravalent mVLP vaccine.

  13. Several domains from VAR2CSA can induce Plasmodium falciparum adhesion-blocking antibodies

    DEFF Research Database (Denmark)

    Salanti, Ali; Resende, Mafalda; Ditlev, Sisse B

    2010-01-01

    ABSTRACT: BACKGROUND: Malaria caused by Plasmodium falciparum can result in several different syndromes with severe clinical consequences for the about 200 million individuals infected each year. During pregnancy, women living in endemic areas become susceptible to malaria due to lack of antibodies...... against a unique P. falciparum membrane protein, named VAR2CSA. This antigen is not expressed in childhood infections, since it binds chondroitin sulphate A (CSA) expressed on the intervillous space in the placenta. A vaccine appears possible because women acquire protective antibodies hindering...... sequestration in the placenta as a function of parity. A challenge for vaccine development is to design small constructs of this large antigen, which can induce broadly protective antibodies. It has previously been shown that one domain of VAR2CSA, DBL4-FCR3, induces parasite adhesion-blocking antibodies...

  14. HAHA--nothing to laugh about. Measuring the immunogenicity (human anti-human antibody response) induced by humanized monoclonal antibodies applying ELISA and SPR technology.

    Science.gov (United States)

    Nechansky, Andreas

    2010-01-05

    Immunogenicity induced by passively applied proteins is a serious issue because it is directly related to the patient's safety. The out-come of an immune reaction to a therapeutic protein can range from transient appearance of antibodies without any clinical significance to severe life threatening conditions. Within this article, enzyme-linked immunosorbent assay (ELISA) and surface plasmon resonance (SPR) methodology to measure immunogenicity are compared and the pros and cons are discussed.

  15. The heptide repeat 2 and upstream region of TGEV induces potent cross-neutralizing antibodies against group I coronaviruses.

    Science.gov (United States)

    Shi, Huiling; Wu, Nannan; Wang, Xiaoming; Wang, Tianhou

    2012-10-01

    The coronavirus heptide repeat (HR) region in the spike protein induces neutralizing antibodies that block the postfusion core formation and inhibit virus entry into target cells. The HR2 regions for coronaviruses of the same serogroup share high homology. We found that polyclonal antibodies derived from transmissible gastroenteritis coronavirus HR2 and upstream region were cross-reactive with the S proteins of the same serogroup in western blotting. The polyclonal antibodies also potently cross-neutralized viruses from the same serogroup. This study provides new insight for designing vaccine and therapeutic reagents against coronavirus infections.

  16. Cell death induced by a {sup 131}I-labeled monoclonal antibody in ovarian cancer multicell spheroids

    Energy Technology Data Exchange (ETDEWEB)

    Filippovich, I.V.; Sorokina, N.; Robillard, N.; Faivre-Chauvet, A.; Bardies, M.; Chatal, J.F

    1996-07-01

    Treatment of OVCAR-3 spheroids with {sup 131}I-OC125 monoclonal antibody produced a decrease in spheroid volume and a concomitant rise in necrotic cell number. No increase in apoptotic cell number was observed during incubation of spheroids with the labeled antibody. Necrosis began early, reaching a maximum after 3 Gy of accumulated dose delivered at a dose rate of 1.8 cGy/h. Higher accumulated doses induced necrosis for longer incubation times. Thus, dose rate and time are both determinants of ultimate radiation effects when spheroids are incubated with labeled antibodies, although dose rate is the most important factor.

  17. C-reactive protein enhances the respiratory burst of neutrophils-induced by antineutrophil cytoplasmic antibody.

    Science.gov (United States)

    Xu, Peng-cheng; Hao, Jian; Yang, Xiao-wei; Chang, Dong-yuan; Chen, Min; Zhao, Ming-hui

    2012-10-01

    Serum C-reactive protein (CRP) was one of the useful biomarkers for evaluating the disease activity in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Cumulating studies proved that CRP was pathogenic in a variety of diseases. In the current study, the in vitro effects of CRP to prime neutrophils for ANCA-induced respiratory burst were investigated with flow cytometry. Without TNF-α in the reactive system, ANCA could only induce a slight level of respiratory burst of neutrophils. CRP could enhance the respiratory burst of neutrophils induced by ANCA against myeloperoxidse [mean fluorescence intensity (MFI, 68.45 ± 16.87 vs. 58.65 ± 15.09, P Heat-treated CRP could not enhance the levels of neutrophils respiratory burst induced by ANCA or increase the expression of membrane proteinase 3 of neutrophils. So CRP can prime neutrophils and enhance the respiratory burst induced by ANCA and might be pathogenic in AAV. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Human anti-mouse antibody response induced by anti-CD4 monoclonal antibody therapy in patients with rheumatoid arthritis.

    Science.gov (United States)

    Horneff, G; Winkler, T; Kalden, J R; Emmrich, F; Burmester, G R

    1991-04-01

    The development of human anti-mouse monoclonal antibodies (HAMAs) was investigated in 10 patients with rheumatoid arthritis (RA) who had undergone an experimental therapeutic trial with an anti-CD4 monoclonal antibody. In this patient group, the antibody 16H5 of the IgG1 isotype had been administered in a median total dosage of 140 mg per treatment cycle. Four patients took part in a second treatment regimen 6-8 weeks later. After the first treatment cycle, detectable HAMAs developed in 5 out of 10 patients. In 4 individuals undergoing a second course of therapy, increases of HAMAs were evident only in the 3 patients with previous HAMA responses. HAMAs were primarily of the IgG isotype, while the presence of rheumatoid factors usually interfered with the detectability of IgM HAMAs. However, using isolated F(ab)2 fragments of the monoclonal reagent used for therapy, HAMAs of the IgM isotype were also detectable. HAMAs of the IgG isotype did not exceed levels of 2.0 mg/liter after a single treatment cycle and 2.2 mg/liter after a repeated cycle. No IgE responses were detectable. Absorption experiments indicated that approximately 25% of the HAMA activity was directed against specific determinants of the 16H5 monoclonal antibody, presumably including anti-idiotypic reactivities. These data demonstrate that HAMAs developed only in a proportion of RA patients treated with the anti-CD4 monoclonal antibody 16H5. However, the amounts were rather low compared to other monoclonal reagents used in cancer patients and were therefore allowed for repeated applications without an apparent loss of efficacy.

  19. Streptococcal-vimentin cross-reactive antibodies induce microvascular cardiac endothelial proinflammatory phenotype in rheumatic heart disease

    Science.gov (United States)

    Delunardo, F; Scalzi, V; Capozzi, A; Camerini, S; Misasi, R; Pierdominici, M; Pendolino, M; Crescenzi, M; Sorice, M; Valesini, G; Ortona, E; Alessandri, C

    2013-01-01

    Summary Rheumatic heart disease (RHD) is characterized by the presence of anti-streptococcal group A antibodies and anti-endothelial cell antibodies (AECA). Molecular mimicry between streptococcal antigens and self proteins is a hallmark of the pathogenesis of rheumatic fever. We aimed to identify, in RHD patients, autoantibodies specific to endothelial autoantigens cross-reactive with streptococcal proteins and to evaluate their role in inducing endothelial damage. We used an immunoproteomic approach with endothelial cell-surface membrane proteins in order to identify autoantigens recognized by AECA of 140 RHD patients. Cross-reactivity of purified antibodies with streptococcal proteins was analysed. Homologous peptides recognized by serum cross-reactive antibodies were found through comparing the amino acid sequence of streptococcal antigens with human antigens. To investigate interleukin (IL)-1R-associated kinase (IRAK1) and nuclear factor-κB (NF-κB) activation, we performed a Western blot analysis of whole extracts proteins from unstimulated or stimulated human microvascular cardiac endothelial cells (HMVEC-C). Adhesion molecule expression and release of proinflammatory cytokines and growth factors were studied by multiplex bead based immunoassay kits. We observed anti-vimentin antibodies in sera from 49% RHD AECA-positive patients. Cross-reactivity of purified anti-vimentin antibodies with heat shock protein (HSP)70 and streptopain streptococcal proteins was shown. Comparing the amino acid sequence of streptococcal HSP70 and streptopain with human vimentin, we found two homologous peptides recognized by serum cross-reactive antibodies. These antibodies were able to stimulate HMVEC-C inducing IRAK and NF-κB activation, adhesion molecule expression and release of proinflammatory cytokines and growth factors. In conclusion, streptococcal–vimentin cross-reactive antibodies were able to activate microvascular cardiac endothelium by amplifying the inflammatory

  20. Neutralizing antibodies obtained in a persistent immune response are effective against deleterious effects induced by the Thalassophryne nattereri fish venom.

    Science.gov (United States)

    Piran-Soares, Ana Amélia; Komegae, Evilin Naname; Souza, Valdênia Maria Oliveira; Fonseca, Luiz Alberto; Lima, Carla; Lopes-Ferreira, Mônica

    2007-06-01

    Thalassophryne nattereri envenoming represents a great cost to North and Northeast Brazilian communities in terms of public healths, leisure and tourism. Victims rapidally develop symptoms as pain, local swelling, erythema followed by intense necrosis that persist for long days. The aim of this work was tested the immune competence of neutralizing antibodies in pre-immunized mice against principal toxic activities induced by venom. During the primary antibody response in mice, an elevation of IgG antibody levels was only observed on day 28. After boosting, high antibody levels were detected between days 49 and 70, with a 12-fold increase in IgG level over control values at day 49. We confirmed the in vitro neutralizing capacity of T. nattereri anti-venom against toxic effects and thereafter we show that neutralizing antibodies obtained in a persistent immune response are more effective, inclusive against edematous reaction. After boosting during the secondary response mice with high antibody levels do not present any alterations in venule or arteriole after topical application of venom on cremaster muscle. In addition, CK activity diminished in these mice with high neutralizing antibody levels corroborating the attenuation of the myonecrotic effect by venom. In addition, we determined the presence of high IgG antibodies levels in patients 6 months after injury by T. nattereri. In conclusion, the presence of neutralizing antibodies against to T. nattereri venom in the serum of pre-immunized mice could change the outcome of lesion at site of posterior envenoming. Antigen-specific antibodies of high affinity in consequence to specific immune response, dependent of T lymphocyte activation, could minimize the symptoms of intense and immediate inflammatory reaction caused by T. nattereri venom. These finding prompt us to the possibility of development of immune therapeutic strategies using specific anti-venom as an efficient intervention for protecting human victims.

  1. Assessment of pulmonary antibodies with induced sputum and bronchoalveolar lavage induced by nasal vaccination against Pseudomonas aeruginosa: a clinical phase I/II study

    Directory of Open Access Journals (Sweden)

    Freihorst Joachim

    2007-08-01

    Full Text Available Abstract Background Vaccination against Pseudomonas aeruginosa is a desirable albeit challenging strategy for prevention of airway infection in patients with cystic fibrosis. We assessed the immunogenicity of a nasal vaccine based on the outer membrane proteins F and I from Pseudomonas aeruginosa in the lower airways in a phase I/II clinical trial. Methods N = 12 healthy volunteers received 2 nasal vaccinations with an OprF-OprI gel as a primary and a systemic (n = 6 or a nasal booster vaccination (n = 6. Antibodies were assessed in induced sputum (IS, bronchoalveolar lavage (BAL, and in serum. Results OprF-OprI-specific IgG and IgA antibodies were found in both BAL and IS at comparable rates, but differed in the predominant isotype. IgA antibodies in IS did not correlate to the respective serum levels. Pulmonary antibodies were detectable in all vaccinees even 1 year after the vaccination. The systemic booster group had higher IgG levels in serum. However, the nasal booster group had the better long-term response with bronchial antibodies of both isotypes. Conclusion The nasal OprF-OprI-vaccine induces a lasting antibody response at both, systemic and airway mucosal site. IS is a feasible method to non-invasively assess bronchial antibodies. A further optimization of the vaccination schedule is warranted.

  2. Cure of Chronic Viral Infection and Virus-Induced Type 1 Diabetes by Neutralizing Antibodies

    Directory of Open Access Journals (Sweden)

    Mette Ejrnaes

    2006-01-01

    Full Text Available The use of neutralizing antibodies is one of the most successful methods to interfere with receptor-ligand interactions in vivo. In particular blockade of soluble inflammatory mediators or their corresponding cellular receptors was proven an effective way to regulate inflammation and/or prevent its negative consequences. However, one problem that comes along with an effective neutralization of inflammatory mediators is the general systemic immunomodulatory effect. It is therefore important to design a treatment regimen in a way to strike at the right place and at the right time in order to achieve maximal effects with minimal duration of immunosuppression or hyperactivation. In this review we reflect on two examples of how short time administration of such neutralizing antibodies can block two distinct inflammatory consequences of viral infection. First, we review recent findings that blockade of IL-10/IL-10R interaction can resolve chronic viral infection and second, we reflect on how neutralization of the chemokine CXCL10 can abrogate virus-induced type 1 diabetes.

  3. Cure of Chronic Viral Infection and Virus-Induced Type 1 Diabetes by Neutralizing Antibodies

    Directory of Open Access Journals (Sweden)

    Mette Ejrnaes

    2006-01-01

    Full Text Available The use of neutralizing antibodies is one of the most successful methods to interfere with receptor–ligand interactions in vivo. In particular blockade of soluble inflammatory mediators or their corresponding cellular receptors was proven an effective way to regulate inflammation and/or prevent its negative consequences. However, one problem that comes along with an effective neutralization of inflammatory mediators is the general systemic immunomodulatory effect. It is, therefore, important to design a treatment regimen in a way to strike at the right place and at the right time in order to achieve maximal effects with minimal duration of immunosuppression or hyperactivation. In this review, we reflect on two examples of how short time administration of such neutralizing antibodies can block two distinct inflammatory consequences of viral infection. First, we review recent findings that blockade of IL-10/IL-10R interaction can resolve chronic viral infection and second, we reflect on how neutralization of the chemokine CXCL10 can abrogate virus-induced type 1 diabetes.

  4. Human vaccination against RH5 induces neutralizing antimalarial antibodies that inhibit RH5 invasion complex interactions

    DEFF Research Database (Denmark)

    Payne, Ruth O; Silk, Sarah E; Elias, Sean C

    2017-01-01

    The development of a highly effective vaccine remains a key strategic goal to aid the control and eventual eradication of Plasmodium falciparum malaria. In recent years, the reticulocyte-binding protein homolog 5 (RH5) has emerged as the most promising blood-stage P. falciparum candidate antigen......-deficient chimpanzee adenovirus serotype 63 (ChAd63), and the attenuated orthopoxvirus modified vaccinia virus Ankara (MVA), encoding RH5 from the 3D7 clone of P. falciparum. Vaccines were administered i.m. in a heterologous prime-boost regimen using an 8-week interval and were well tolerated. Vaccine-induced anti-RH5...... serum antibodies exhibited cross-strain functional growth inhibition activity (GIA) in vitro, targeted linear and conformational epitopes within RH5, and inhibited key interactions within the RH5 invasion complex. This is the first time to our knowledge that substantial RH5-specific responses have been...

  5. Dapsone hydroxylamine induces premature removal of human erythrocytes by membrane reorganization and antibody binding

    Science.gov (United States)

    Bordin, Luciana; Fiore, Cristina; Zen, Francesco; Coleman, Michael D; Ragazzi, Eugenio; Clari, Giulio

    2010-01-01

    BACKGROUND AND PURPOSE N-hydroxylation of dapsone leads to the formation of the toxic hydroxylamines responsible for the clinical methaemoglobinaemia associated with dapsone therapy. Dapsone has been associated with decreased lifespan of erythrocytes, with consequences such as anaemia and morbidity in patients treated with dapsone for malaria. Here, we investigated how dapsone and/or its hydroxylamine derivative (DDS-NHOH) induced erythrocyte membrane alterations that could lead to premature cell removal. EXPERIMENTAL APPROACH Erythrocytes from healthy donors were subjected to incubation with dapsone and DDS-NHOH for varying times and the band 3 protein tyrosine-phosphorylation process, band 3 aggregation, membrane alteration and IgG binding were all examined and compared with erythrocytes from two patients receiving dapsone therapy. KEY RESULTS The hydroxylamine derivative, but not dapsone (the parent sulphone) altered membrane protein interactions, leading both to aggregation of band 3 protein and to circulating autologous antibody binding, shown in erythrocytes from patients receiving dapsone therapy. The band 3 tyrosine-phosphorylation process can be used as a diagnostic system to monitor membrane alterations both in vitro, assessing concentration and time-dependent effects of DDS-NHOH treatment, and in vivo, evaluating erythrocytes from dapsone-treated patients, in resting or oxidatively stimulated conditions. CONCLUSIONS AND IMPLICATIONS DDS-NHOH-induced alterations of human erythrocytes can be directly monitored in vitro by tyrosine-phosphorylation level and formation of band 3 protein aggregates. The latter, together with antibody-mediated labelling of erythrocytes, also observed after clinical use of dapsone, may lead to shortening of erythrocyte lifespan. PMID:20662842

  6. Exacerbation of collagen antibody-induced arthritis in transgenic mice overexpressing peroxiredoxin 6.

    Science.gov (United States)

    Kim, Dae Hwan; Lee, Dong Hun; Jo, Mi Ran; Son, Dong Ju; Park, Mi Hee; Hwang, Chul Ju; Park, Ju Ho; Yuk, Dong Yeon; Yoon, Do Young; Jung, Young-Suk; Kim, Youngsoo; Jeong, Jae Hwang; Han, Sang Bae; Hong, Jin Tae

    2015-11-01

    Peroxiredoxin 6 plays important and complex roles in the process of inflammation, but its role in the development of rheumatoid arthritis (RA) remains unclear. We undertook this study to investigate the roles and mechanisms of peroxiredoxin 6 in the development of collagen antibody-induced arthritis (CAIA) and antigen-induced arthritis (AIA) in peroxiredoxin 6-overexpressing transgenic mice, in peroxiredoxin 6-transfected RAW 264.7 cells, in macrophages isolated from peroxiredoxin 6-overexpressing transgenic mice, and in synoviocytes from arthritis patients. CAIA and AIA were induced using standard methods. Peroxiredoxin 6-transfected RAW 264.7 cells, macrophages isolated from peroxiredoxin 6-overexpressing transgenic mice, and synoviocytes from arthritis patients were used to study proinflammatory responses and mechanisms. Clinical scores and histopathologic changes were determined in peroxiredoxin 6-overexpressing transgenic mice and wild-type (WT) mice with CAIA or AIA. Generation of nitric oxide (NO), expression of inducible NO synthase and cyclooxygenase 2, and activity of NF-κB and activator protein 1 (AP-1) were determined in cultured macrophages and synoviocytes as well as in joint tissue from mice by Western blotting, electrophoretic mobility shift assay, and immunohistochemical analysis. Development of CAIA and AIA and proinflammatory responses were more exacerbated in peroxiredoxin 6-overexpressing transgenic mice than in WT mice. Overexpression of peroxiredoxin 6 increased lipopolysaccharide-induced inflammatory responses in RAW 264.7 cells, in macrophages isolated from peroxiredoxin 6-overexpressing transgenic mice, and in synoviocytes from arthritis patients, and this was accompanied by up-regulation of the JNK pathway. Moreover, a JNK inhibitor completely blocked RA development and proinflammatory responses. Our findings suggest that overexpression of peroxiredoxin 6 might promote development of RA through NF-κB and AP-1 activity via the JNK

  7. Intrinsic insulin secretion capacity might be preserved by discontinuing anti-programmed cell death protein 1 antibody treatment in 'anti-programmed cell death protein 1 antibody-induced' fulminant type 1 diabetes.

    Science.gov (United States)

    Sakai, Gota; Saito, Daigo; Nakajima, Ritsuko; Hatano, Masako; Noguchi, Yuichi; Kurihara, Susumu; Katayama, Shigehiro; Inoue, Ikuo; Noda, Mitsuhiko; Shimada, Akira

    2018-03-01

    Intrinsic insulin secretion capacity may be preserved by discontinuing anti-PD-1 antibody treatment in 'anti-PD-1 antibody-induced'fulminant type 1 diabetes. © 2018 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

  8. Source and role of diacylglycerol formed during phagocytosis of opsonized yeast particles and associated respiratory burst in human neutrophils

    International Nuclear Information System (INIS)

    Della Bianca, V.; Grzeskowiak, M.; Lissandrini, D.; Rossi, F.

    1991-01-01

    The results presented in this paper demonstrate that in human neutrophils phagocytosis of C3b/bi and IgG-opsonized yeast particles is associated with activation of phospholipase D and that this reaction is the main source of diglycerides. The demonstration is based upon the following findings: (1) the challenge of neutrophils with these opsonized particles was followed by a rapid formation of [3H]alkyl-phosphatidic acid [( 3H]alkyl-PA) and [3H]alkyl-diglyceride [( 3H]alkyl-DG) in cells labeled with [3H]alkyl-lyso-phosphatidylcholine; (2) in the presence of ethanol [3H]alkyl-phosphatidylethanol was formed, and accumulation of [3H]alkyl-PA and [3H]alkyl-DG was depressed; (3) propranolol, by inhibiting the dephosphorylation of [3H]alkyl-PA, completely inhibited the accumulation of [3H]alkyl-DG and depressed by about 75% the formation of diglyceride mass. Evidence is also presented that phagocytosis of C3b/bi and IgG-opsonized yeast particles and associated respiratory burst can take place independently of diglyceride formation and of the activity of this second messenger on protein kinase C. In fact: (a) propranolol while completely inhibited the formation of diglyceride mass did not modify either the phagocytosis or respiratory burst; (b) these two processes were insensitive to staurosporine

  9. Anti-TNF-alpha antibody attenuates subarachnoid hemorrhage-induced apoptosis in the hypothalamus by inhibiting the activation of Erk

    Directory of Open Access Journals (Sweden)

    Ma L

    2018-02-01

    Full Text Available Ling Ma,1 Yong Jiang,2 Yanan Dong,2 Jun Gao,2 Bin Du,2 Dianwei Liu2 1Department of Clinical Laboratory, The Second Hospital of Shandong University, Jinan, Shandong, People’s Republic of China; 2Department of Neurosurgery, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong, People’s Republic of China Background: Subarachnoid hemorrhage (SAH can induce apoptosis in many regions of the brain including the cortex and hippocampus. However, few studies have focused on apoptosis in the hypothalamus after SAH. Although some antiapoptotic strategies have been developed for SAH, such as anti-tumor necrosis factor-alpha (TNF-α antibody, the molecular mechanisms underlying this condition have yet to be elucidated. Therefore, the purpose of this study was to evaluate whether SAH could induce apoptosis in the hypothalamus and identify the potential molecular mechanisms underlying the actions of anti-TNF-α antibody, as a therapeutic regimen, upon apoptosis. Materials and methods: SAH was induced in a rat model. Thirty minutes prior to SAH, anti-TNF-α antibody or U0126, an extracellular signal-regulated kinase (Erk inhibitor, was microinjected into the left lateral cerebral ventricle. In addition, phorbol-12-myristate-13-acetate was injected intraperitoneally immediately after the anti-TNF-α antibody microinjection. Then, real-time polymerase chain reaction, Western blotting and immunohistochemistry were used to detect the expression of caspase-3, bax, bcl-2, phosphorylated Erk (p-Erk and Erk. Finally, anxiety-like behavior was identified by using open field. Results: Levels of caspase-3, bax and bcl-2, all showed a temporary rise after SAH in the hypothalamus, indicating the induction of apoptosis in this brain region. Interestingly, we found that the microinjection of anti-TNF-α antibody could selectively block the elevated levels of bax, suggesting the potential role of anti-TNF-α antibody in the inhibition of SAH-induced

  10. Stealth nanotubes: strategies of shielding carbon nanotubes to evade opsonization and improve biodistribution

    Science.gov (United States)

    Kotagiri, Nalinikanth; Kim, Jin-Woo

    2014-01-01

    Carbon nanotubes (CNTs) have recently been in the limelight for their potential role in disease diagnostics and therapeutics, as well as in tissue engineering. Before these medical applications can be realized, there is a need to address issues like opsonization, phagocytosis by macrophages, and sequestration to the liver and spleen for eventual elimination from the body; along with equally important issues such as aqueous solubility, dispersion, biocompatibility, and biofunctionalization. CNTs have not been shown to be able to evade such biological obstacles, which include their nonspecific attachments to cells and other biological components in the bloodstream, before reaching target tissues and cells in vivo. This will eventually determine their longevity in circulation and clearance rate from the body. This review article discusses the current status, challenges, practical strategies, and implementations of coating CNTs with biocompatible and opsonin-resistant moieties, rendering CNTs transparent to opsonins and deceiving the innate immune response to make believe that the CNTs are not foreign. A holistic approach to the development of such “stealth” CNTs is presented, which encompasses not only several biophysicochemical factors that are not limited to surface treatment of CNTs, but also extraneous biological factors such as the protein corona formation that inevitably controls the in vivo fate of the particles. This review also discusses the present and potential applications, along with the future directions, of CNTs and their hybrid-based nanotheranostic agents for multiplex, multimodal molecular imaging and therapy, as well as in other applications, such as drug delivery and tissue engineering. PMID:24872705

  11. Adenovirus Particles that Display the Plasmodium falciparum Circumsporozoite Protein NANP Repeat Induce Sporozoite-Neutralizing Antibodies in Mice

    OpenAIRE

    Palma, Christopher; Overstreet, Michael G.; Guedon, Jean-Marc; Hoiczyk, Egbert; Ward, Cameron; Karen, Kasey A.; Zavala, Fidel; Ketner, Gary

    2011-01-01

    Adenovirus particles can be engineered to display exogenous peptides on their surfaces by modification of viral capsid proteins, and particles that display pathogen-derived peptides can induce protective immunity. We constructed viable recombinant adenoviruses that display B-cell epitopes from the Plasmodium falciparum circumsporozoite protein (PfCSP) in the major adenovirus capsid protein, hexon. Recombinants induced high-titer antibodies against CSP when injected intraperitoneally into mice...

  12. Vaccination against Streptococcus pneumoniae does not induce antibodies against HLA or MICA in clinically stable kidney transplant recipients.

    Science.gov (United States)

    Lindemann, Monika; Heinemann, Falko M; Horn, Peter A; Witzke, Oliver

    2013-10-01

    There are concerns in the community that immune activation after vaccination could lead to (subclinical) rejection. Our aim was to define if pneumococcal vaccination induced HLA antibodies using highly sensitive methods. Forty-nine kidney transplant recipients were immunized with Pneumovax 23. The median interval between transplantation and vaccination was 6.5 years, the median serum creatinine concentration 1.3, 1.3 and 1.4 mg/dL pre-vaccination, at month 1 and 15 post-vaccination, respectively. In none of the patients biopsy-proven acute rejection was diagnosed within three years post-vaccination. Pneumococcal, HLA class I and II and major histocompatibility class I-related chain A (MICA) antibodies were determined by Luminex™ technology (xMAP™ Pneumococcal Immunity Panel and LABScreen™ Mixed beads, respectively) and HLA antibodies also by ELISA (Lambda Antigen Tray™). While pneumococcal antibodies were significantly higher at month 1 and 15 post- vs. pre-vaccination (p<0.0001 each), HLA/MICA antibodies remained unchanged as determined by Luminex™ and ELISA. Positive Luminex™ reactions were present in 63%, 67% and 63% (HLA class I), 47%, 47% and 55% (HLA class II) and 29%, 29% and 29% (MICA) pre-vaccination, at month 1 and 15, respectively. In clinically stable kidney transplant recipients there is no evidence for an increase in HLA antibodies after pneumococcal vaccination. Copyright © 2013 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  13. Antibody-induced generation of reactive oxygen radicals by brain macrophages in canine distemper encephalitis: a mechanism for bystander demyelination.

    Science.gov (United States)

    Griot, C; Bürge, T; Vandevelde, M; Peterhans, E

    1989-01-01

    The mechanism of inflammatory demyelination in canine distemper encephalitis (CDE) is uncertain but macrophages are thought to play an important effector role in this lesion. Serum and cerebrospinal fluid (CSF), containing anti-canine distemper virus and anti-myelin antibodies from dogs with CDE were tested for their ability to generate reactive oxygen species (ROS) in macrophages in primary dog brain cell cultures using a chemiluminescence (CL) assay. The majority of serum samples and several CSF samples from animals with inflammatory demyelination elicited a CL signal in infected dog brain cell cultures. In contrast, none of these samples induced a positive response in uninfected cultures which contained large numbers of myelin antigen-presenting cells, although defined anti-myelin antibodies lead to a marked secretion of ROS in this system. It was concluded that antiviral antibody-induced secretion of ROS, known to be highly toxic for brain tissue, may play an important role in white matter damage in inflammatory lesions supporting a previous hypothesis of bystander demyelination in CDE. No evidence was found for a similar antibody-dependent cellular cytotoxicity-like mechanism mediated by anti-myelin antibodies in CDE, which does not support the concept of autoimmunity in this disease.

  14. CXCR4-derived synthetic peptides inducing anti-HIV-1 antibodies.

    Science.gov (United States)

    Hashimoto, Chie; Nomura, Wataru; Narumi, Tetsuo; Fujino, Masayuki; Nakahara, Toru; Yamamoto, Naoki; Murakami, Tsutomu; Tamamura, Hirokazu

    2013-11-15

    Despite almost 30 years since the identification of the human immunodeficiency virus type I (HIV-1), development of effective AIDS vaccines has been hindered by the high mutability of HIV-1. The HIV-1 co-receptors CCR5 and CXCR4 are genetically stable, but viral proteins may mutate rapidly during the course of infection. CXCR4 is a seven transmembrane G protein-coupled receptor, possessing an N-terminal region (NT) and three extracellular loops (ECL1-3). Previous studies have shown that the CXCR4-ED-derived peptides inhibit the entry of HIV-1 by interacting with gp120, an HIV-1 envelope glycoprotein. In the present study, antigenicity of CXCR4-derived peptides has been investigated and the anti-HIV-1 effects of induced antisera have been assessed. It was found that CXCR4-ED-derived antigen molecules immunize mice, showing that the linear peptides have higher antigenicity than the cyclic peptides. The L1- and L2-induced antisera inhibited the HIV-1 entry significantly, while anti-N1 antibodies have no inhibitory activity. This study produced promising examples for the design of AIDS vaccines which target the human protein and can overcome mutability of HIV-1. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. DNA-dependent protein kinase inhibits AID-induced antibody gene conversion.

    Directory of Open Access Journals (Sweden)

    Adam J L Cook

    2007-04-01

    Full Text Available Affinity maturation and class switching of antibodies requires activation-induced cytidine deaminase (AID-dependent hypermutation of Ig V(DJ rearrangements and Ig S regions, respectively, in activated B cells. AID deaminates deoxycytidine bases in Ig genes, converting them into deoxyuridines. In V(DJ regions, subsequent excision of the deaminated bases by uracil-DNA glycosylase, or by mismatch repair, leads to further point mutation or gene conversion, depending on the species. In Ig S regions, nicking at the abasic sites produced by AID and uracil-DNA glycosylases results in staggered double-strand breaks, whose repair by nonhomologous end joining mediates Ig class switching. We have tested whether nonhomologous end joining also plays a role in V(DJ hypermutation using chicken DT40 cells deficient for Ku70 or the DNA-dependent protein kinase catalytic subunit (DNA-PKcs. Inactivation of the Ku70 or DNA-PKcs genes in DT40 cells elevated the rate of AID-induced gene conversion as much as 5-fold. Furthermore, DNA-PKcs-deficiency appeared to reduce point mutation. The data provide strong evidence that double-strand DNA ends capable of recruiting the DNA-dependent protein kinase complex are important intermediates in Ig V gene conversion.

  16. Cross-reactive antibodies induced by xenogeneic IgA can cause selective IgA deficiency.

    Science.gov (United States)

    Klartag, Ayelet; Chen, Chiann-Chyi; Dougherty, Joseph P; Ron, Yacov

    2010-03-01

    Selective immunoglobulin A deficiency (sIgAD) is the most common immunodeficiency in humans. Auto-reactive antibodies to human immunoglobulin A (IgA) are found in the serum of 20-40% of individuals with sIgAD. It is unknown whether these antibodies play a role in the pathogenesis of this immunodeficiency and although the prevailing thought is that they are secondary to the onset of sIgAD, there is very little, if any, support for this notion. Here, we propose that anti-IgA antibodies are in fact responsible for the removal of IgA from serum, and that the inducing antigen is most probably a xenogeneic IgA. This hypothesis is based on data obtained from an sIgAD patient in whom changes in dietary consumption of beef and/or bovine dairy products resulted in changes in anti-IgA levels in the serum. To test the hypothesis, the presence of anti-bovine IgA antibodies was tested by a highly specific enzyme-linked immunosorbent assay in serum samples from IgA-deficient and control individuals. All 13 sIgAD individuals with anti-IgA antibodies had a higher titer against bovine IgA than against human IgA. Of 23 control individuals, a surprisingly high proportion (65%) was also found to have IgG anti-bovine IgA antibodies. These results support the hypothesis that the anti-human IgA antibodies found in IgA-deficient individuals are originally produced against bovine IgA. These antibodies are found in many normal individuals, but only in cases where they cross react with endogenous human IgA, sIgAD may develop.

  17. Murine CR1/2 targeted antigenized single-chain antibody fragments induce transient low affinity antibodies and negatively influence an ongoing immune response.

    Science.gov (United States)

    Prechl, József; Molnár, Eszter; Szekeres, Zsuzsanna; Isaák, Andrea; Papp, Krisztián; Balogh, Péter; Erdei, Anna

    2007-01-01

    We have generated a single-chain antibody which recognizes murine CR1/2 and carries a genetically fused influenza hemagglutinin derived peptide. Theoretically such a construct is able to crosslink the B cell antigen receptor and CR1/2 on peptide specific B cells. The construct was able to reach its CR1/2 positive target cells, yet intraperitoneal delivery of the construct elicited an IgM response only slightly exceeding that induced by the free peptide. Providing T cell help by the injection of peptide specific lymphocytes did not alter the response in essence, that is anti-peptide IgG was not detectable even after booster immunizations. When used as a booster vaccine following injection of the peptide in adjuvant, the construct even inhibited the development of IgG1 and IgG3 anti-peptide antibodies. These data indicate that although targeting of antigen to CR1/2 on B cells can enhance transient proliferation or differentiation of antigen specific B cells it cannot induce strong, longlasting humoral immune responses. Furthermore, CR1/2 targeting constructs may negatively influence an ongoing immune reaction.

  18. Precisely Molded Nanoparticle Displaying DENV-E Proteins Induces Robust Serotype-Specific Neutralizing Antibody Responses.

    Directory of Open Access Journals (Sweden)

    Stefan W Metz

    2016-10-01

    Full Text Available Dengue virus (DENV is the causative agent of dengue fever and dengue hemorrhagic fever. The virus is endemic in over 120 countries, causing over 350 million infections per year. Dengue vaccine development is challenging because of the need to induce simultaneous protection against four antigenically distinct DENV serotypes and evidence that, under some conditions, vaccination can enhance disease due to specific immunity to the virus. While several live-attenuated tetravalent dengue virus vaccines display partial efficacy, it has been challenging to induce balanced protective immunity to all 4 serotypes. Instead of using whole-virus formulations, we are exploring the potentials for a particulate subunit vaccine, based on DENV E-protein displayed on nanoparticles that have been precisely molded using Particle Replication in Non-wetting Template (PRINT technology. Here we describe immunization studies with a DENV2-nanoparticle vaccine candidate. The ectodomain of DENV2-E protein was expressed as a secreted recombinant protein (sRecE, purified and adsorbed to poly (lactic-co-glycolic acid (PLGA nanoparticles of different sizes and shape. We show that PRINT nanoparticle adsorbed sRecE without any adjuvant induces higher IgG titers and a more potent DENV2-specific neutralizing antibody response compared to the soluble sRecE protein alone. Antigen trafficking indicate that PRINT nanoparticle display of sRecE prolongs the bio-availability of the antigen in the draining lymph nodes by creating an antigen depot. Our results demonstrate that PRINT nanoparticles are a promising platform for delivering subunit vaccines against flaviviruses such as dengue and Zika.

  19. Anti-thromboxane B2 antibodies protect against acetaminophen-induced liver injury in mice

    Directory of Open Access Journals (Sweden)

    Ivan Ćavar

    2011-12-01

    Full Text Available Prostanoids are lipid compounds that mediate a variety of physiological and pathological functions in almost all body tissues and organs. Thromboxane (TX A2 is a powerful inducer of platelet aggregation and vasoconstriction and it has ulcerogenic activity in the gastrointestinal tract. Overdose or chronic use of a high dose of acetaminophen (N-acetyl-paminophenol, APAP is a major cause of acute liver failure in the Western world. We investigated whether TXA2 plays a role in host response to toxic effect of APAP. CBA/H Zg mice of both sexes were intoxicated with a single lethal or high sublethal dose of APAP, which was administered to animals by oral gavage. The toxicity of APAP was determined by observing the survival of mice during 48 h, by measuring concentration of alanine-aminotransferase (ALT in plasma 20-22 h after APAP administration and by liver histology. The results have shown that anti-thromboxane (TX B2 antibodies (anti-TXB2 and a selective inhibitor of thromboxane (TX synthase, benzylimidazole (BZI, were significantly hepatoprotective, while a selective thromboxane receptor (TPR antagonist, daltroban, was slightly protective in this model of acute liver injury. A stabile metabolite of TXA2, TXB2, and a stabile agonist of TPR, U-46619, had no influence on APAP-induced liver damage. Our findings suggest that TXA2 has a pathogenic role in acute liver toxicity induced with APAP, which was highly abrogated by administration of anti-TXB2. According to our results, this protection is mediated, at least in part, through decreased production of TXB2 by liver fragments ex vivo.

  20. Pharmacological concentrations of recombinant factor VIIa restore hemostasis independent of tissue factor in antibody-induced hemophilia mice.

    Science.gov (United States)

    Keshava, S; Sundaram, J; Rajulapati, A; Pendurthi, U R; Rao, L V M

    2016-03-01

    ESSENTIALS: The role of tissue factor (TF) in recombinant factor VIIa (rFVIIa) therapy in hemophilia is unclear. An acquired mouse hemophilia model with very low or normal levels of human TF was used in the study. rFVIIa is equally effective in correcting the bleeding in mice expressing low or normal levels of TF. Pharmacological doses of rFVIIa restore hemostasis in hemophilia independent of TF. Recombinant factor VIIa (rFVIIa) has been used widely for treating hemophilia patients with inhibitory autoantibodies against factor VIII or IX. Its mechanism of action is not entirely known. A majority of in vitro studies suggested that pharmacological concentrations of rFVIIa restore hemostasis in hemophilia in a phospholipid-dependent manner, independent of tissue factor (TF). However, a few studies suggested that a TF-dependent mechanism has a primary role in correction of bleeding by rFVIIa in hemophilia patients. Here, we investigated the potential contribution of TF in rFVIIa-induced hemostasis in hemophilia employing a model system of FVIII antibody-induced hemophilia in TF transgenic mice. Mice expressing low levels of human TF (LTF mice), mice expressing relatively high levels of human TF (HTF mice) and wild-type mice (WT mice) had neutralizing anti-FVIII antibodies administered in order to induce hemophilia in these mice. The mice were then treated with varying concentrations of rFVIIa. rFVIIa-induced hemostasis was evaluated with the saphenous vein bleeding model. Administration of FVIII inhibitory antibodies induced the hemophilic bleeding phenotype in all three genotypes. rFVIIa administration rescued the bleeding phenotype in all three genotypes. No significant differences were observed in rFVIIa-induced correction of bleeding between LTF and HTF mice that had FVIII antibodies administered. Our results provide strong evidence supporting the suggestion that the hemostatic effect of pharmacological doses of rFVIIa stems from a TF-independent mechanism. © 2016

  1. Treatment of patients with a history of heparin-induced thrombocytopenia and anti-lepirudin antibodies with argatroban.

    Science.gov (United States)

    Harenberg, Job; Job, Harenberg; Jörg, Ingrid; Ingrid, Jörg; Fenyvesi, Tivadar; Tivadar, Fenyvesi; Piazolo, Lukas; Lukas, Piazolo

    2005-02-01

    Patients with heparin-induced thrombocytopenia (HIT) type II require anticoagulation with non-heparin immediate acting anticoagulants. Danaparoid may cross react with HIT-antibodies and lepirudin may generate anti-lepirudin antibodies influencing anticoagulation. We hypothesised, that the synthetic small molecular thrombin inhibitor argatroban does not induce immunoglobulins reacting towards lepirudin in patients with anti-lepirudin antibodies in the history and that titration of the anticoagulation may be easier with argatroban. We report on the treatment of four patients of a study, which was terminated prematurely due to official warnings for a repeated use of lepirudin. Two patients each received argatroban and lepirudin intravenously. A blinded assessor adjusted the doses of the anticoagulants to 1.5-3.0 fold prolongation of the aPTT. Ecarin clotting time (ECT), concentrations of lepirudin (ELISA) and of argatroban (gas-chromatography with mass spectrometry), and the generation of lepirudin antibodies (ELISA) were measured. APTT-adjusted dosages for argatroban was 2.0-2.6 microg/kg.min and for lepirudin 48-149 microg/kg.h. ECT was prolonged 2.1 to 4.5-fold with lepirudin and 4 to 7-fold with argatroban. The concentration of lepirudin ranged between 750 and 1500 ng/ml and of argatroban between 400 and 1100 ng/ml. Patients on argatroban did not generate immunoglobulin IgG reacting towards lepirudin in contrast to both patients on lepirudin who developed anti-lepirudin antibodies. Both treatments were well tolerated. Despite the low number of patients argatroban seems to lead to a more stable anticoagulant response than lepirudin resulting in a lower variability of the dosage for prophylaxis or treatment of thromboembolism of patients with a history of HIT and lepirudin antibodies.

  2. Antibodies in human serum and milk induced by enterobacteria and food proteins.

    Science.gov (United States)

    Ahlstedt, S; Carlsson, B; Fällström, S P; Hanson, L A; Holmgren, J; Lidin-Janson, G; Lindblad, B S; Jodal, U; Kaijser, B; Solh-Akerlund, A; Wadsworth, C

    Ingestion of Escherichia coli O83 bacteria by adults resulted in a transient irregular colonization leading to a serum antibody response in only four out of 14 cases examined. In all of three pregnant women, however, IgA antibodies against E. coli O83 antigen were released from colostral cells after similar bacterial ingestion although no serum antibody response was noted. The findings indicate a link between the antigenic exposure to the gut and secretory antibodies of the IgA class, presumably locally formed in the mammary gland. Antibodies of the secretory IgA class registered in colostrum may, at least partly, reflect the antigenic exposure of the gut. These antibodies are probably important in protecting against E. coli infections in the neonate, as suggested by the findings of antibodies in human milk against O and K antigens of non-enteropathogenic as well as enteropathogenic serotypes of E. coli. Furthermore, in milk of women from low socio-economic groups in Pakistan, neutralizing antibodies were present against enterotoxins of E. coli bacteria and occasionally against Vibrio cholerae enterotoxins. In addition, secretory IgA antibodies against food proteins were detected in human milk. This suggests that intestinal exposure to such antigens could stimulate a local immune response in the gut resulting in triggered lymphoid cells homing to the mammary gland. These human milk secretory IgA antibodies against bovine milk proteins may help to prevent cow's milk allergy in infants on mixed feeding, since these infants tend to have a lower serum antibody response to cow's milk proteins than infants fed mostly artificially. Furthermore, children suffering from cow's milk protein intolerance and gluten enteropathy may have higher serum levels of antibody to cow's milk protein antigens than normal children, possibly reflecting increased permeability of the intestinal mucosa for various antigens.

  3. Activation and binding of opsonic fragments of C3 on encapsulated Cryptococcus neoformans by using an alternative complement pathway reconstituted from six isolated proteins.

    Science.gov (United States)

    Kozel, T R; Wilson, M A; Pfrommer, G S; Schlageter, A M

    1989-07-01

    Encapsulated Cryptococcus neoformans yeast cells are potent activators of the complement system. We examined the interaction of the yeast cells with an alternative complement pathway reconstituted from isolated factor D, factor B, factor H, factor I, C3, and properdin. Incubation of encapsulated cryptococci with the reconstituted pathway led to activation and binding of C3 fragments to the yeast cells that was quantitatively and qualitatively identical to that observed with normal human serum. Incubation with either normal serum or a mixture of isolated proteins led to binding of 4 x 10(7) to 5 x 10(7) C3 molecules to the yeast cells. The kinetics for activation and binding of C3 were identical, with maximum binding observed after a 20-min incubation. Immunoglobulin G was not needed for optimal activation kinetics. C3 fragments eluted from the yeast cells by treatment with hydroxylamine and subsequent analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis demonstrated the presence primarily of iC3b on yeast cells incubated with either normal serum or the reconstituted pathway. Ultrastructural examination of the opsonized yeast cells showed that the cryptococcal capsule was the site for binding of C3 activated from normal serum or the reconstituted pathway, with a dense accumulation of C3 at the periphery of the capsule. Thus, incubation of encapsulated cryptococci in the reconstituted pathway led to deposition of opsonic complement fragments at a site that was appropriate for interaction with phagocyte receptors. Cryptococci opsonized with the reconstituted pathway showed a markedly enhanced interaction with cultured human monocytes compared with unopsonized yeast cells, indicating that the alternative pathway alone is opsonic for yeast cells. However, the results indicate that additional serum factors are needed for optimal opsonization of yeast cells because a 35% reduction in the number of cryptococci bound to macrophages was observed with

  4. Kinetic and HPV infection effects on cross-type neutralizing antibody and avidity responses induced by Cervarix®

    Science.gov (United States)

    Kemp, Troy J.; Safaeian, Mahboobeh; Hildesheim, Allan; Pan, Yuanji; Penrose, Kerri J.; Porras, Carolina; Schiller, John T.; Lowy, Douglas R.; Herrero, Rolando; Pinto, Ligia A.

    2012-01-01

    Background We previously demonstrated that Cervarix® elicits antibody responses against vaccine-related types for which clinical efficacy was demonstrated (HPV-31 and -45). Here, we evaluated the kinetics of neutralization titers and avidity of Cervarix®-induced antibodies up to 36 months of follow-up in unexposed and HPV infected women. Methods A subset of women who participated in the Cost Rica HPV-16/18 Vaccine Trial had pre- and post-vaccination sera tested for antibody responses to HPV-16, -18, -31, -45, and -58 using a pseudovirion-based neutralization assay, and HPV-16 antibody avidity using an HPV-16 L1 VLP (virus-like particle)-based ELISA developed in our laboratory. Results In uninfected women, neutralizing antibody titers did not reach significance until after the 3rd dose for HPV-31 (month 12, p=0.009) and HPV-45 (month 12, p=0.003), but then persisted up to month 36 (HPV-31, p=0.01; HPV-45, p=0.002). Individuals infected with HPV-16 or HPV-31 at enrollment developed a significantly higher median antibody response to the corresponding HPV type after one dose, but there was not a difference between median titers after three doses compared to the HPV negative group. Median HPV-16 antibody avidity and titer increased over time up to month 12; however, the HPV-16 avidity did not correlate well with HPV-16 neutralizing antibody titers at each time point examined, except for month 6. The median avidity levels were higher in HPV-16 infected women at month 1 (p=0.04) and lower in HPV-16 infected women at month 12 (p=0.006) compared to the HPV negative women. Conclusions The persistence of cross-neutralization titers at month 36 suggests cross-reactive antibody responses are likely to persist long-term and are not influenced by infection status at enrollment. However, the weak correlation between avidity and neutralization titers emphasizes the need for examining avidity in efficacy studies to determine if high avidity antibodies play a critical role in

  5. 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.

  6. Unveiling Unexpected Immune Activities Induced by Your Pneumococcal Vaccine

    Directory of Open Access Journals (Sweden)

    Julia L. Hurwitz

    2016-03-01

    Full Text Available In modern-day vaccine design, a good pneumococcal capsular polysaccharide vaccine is measured by its ability to induce opsonic antibodies. These antibodies label bacteria for phagocytosis by neutrophils and thereby overcome the capsule’s barrier function. Doyle and Pirofski have raised a serious challenge to the current paradigm by describing anti-capsular antibodies that are highly protective but nonopsonic [C.R. Doyle and L. Pirofski, mBio 7(1:e02260-15, 2016, doi:10.1128/mBio.02260-15]. In fact, some functions are not related to neutrophils or phagocytosis at all. An increased awareness of these activities is critical not only for accurate comparisons of vaccine candidates but also for improvements in vaccination outcomes in settings of neutropenia. When vaccine developers select a single gatekeeper assay (e.g., an opsonophagocytic assay for bacteria or a neutralization assay for viruses, promising vaccine candidates may be missed. Doyle and Pirofski stress that multiple functions, not just one, should be investigated to enhance discovery of antibody mechanisms and to best assess vaccine-induced correlates of immune protection.

  7. Ebola virus-like particles produced in insect cells exhibit dendritic cell stimulating activity and induce neutralizing antibodies

    International Nuclear Information System (INIS)

    Ye Ling; Lin Jianguo; Sun Yuliang; Bennouna, Soumaya; Lo, Michael; Wu Qingyang; Bu Zhigao; Pulendran, Bali; Compans, Richard W.; Yang Chinglai

    2006-01-01

    Recombinant baculoviruses (rBV) expressing Ebola virus VP40 (rBV-VP40) or GP (rBV-GP) proteins were generated. Infection of Sf9 insect cells by rBV-VP40 led to assembly and budding of filamentous particles from the cell surface as shown by electron microscopy. Ebola virus-like particles (VLPs) were produced by coinfection of Sf9 cells with rBV-VP40 and rBV-GP, and incorporation of Ebola GP into VLPs was demonstrated by SDS-PAGE and Western blot analysis. Recombinant baculovirus infection of insect cells yielded high levels of VLPs, which were shown to stimulate cytokine secretion from human dendritic cells similar to VLPs produced in mammalian cells. The immunogenicity of Ebola VLPs produced in insect cells was evaluated by immunization of mice. Analysis of antibody responses showed that most of the GP-specific antibodies were of the IgG2a subtype, while no significant level of IgG1 subtype antibodies specific for GP was induced, indicating the induction of a Th1-biased immune response. Furthermore, sera from Ebola VLP immunized mice were able to block infection by Ebola GP pseudotyped HIV virus in a single round infection assay, indicating that a neutralizing antibody against the Ebola GP protein was induced. These results show that production of Ebola VLPs in insect cells using recombinant baculoviruses represents a promising approach for vaccine development against Ebola virus infection

  8. Complement plays a central role in Candida albicans-induced cytokine production by human PBMCs

    DEFF Research Database (Denmark)

    Cheng, Shih-Chin; Sprong, Tom; Joosten, Leo A B

    2012-01-01

    In experimental studies, the role of complement in antifungal host defense has been attributed to its opsonizing capability. In this study, we report that in humans an activated complement system mainly augments Candida albicans-induced host proinflammatory cytokine production via C5a-C5a......R signaling, while phagocytosis and intracellular killing of Candida are not influenced. By blocking the C5a-C5aR signaling pathway, either with anti-C5a antagonist antibodies or with the C5aR antagonist W-54001, C. albicans-induced IL-6 and IL-1β levels were significantly reduced. Recombinant C5a augmented...... in augmenting host proinflammatory cytokine production upon contact with C. albicans, and define the role of the complement system in anti-Candida host defense in humans....

  9. Immunologic and functional characterization of anti-HLA-DR rabbit antibodies induced by synthetic peptides.

    Science.gov (United States)

    Chersi, A; Schulz, G; Houghten, R A

    1984-10-01

    Three peptides selected from the amino acid sequence of the alpha- and beta-chains of DR2 histocompatibility antigens were chemically synthesized and coupled to carrier proteins to be used as immunogens in rabbits. This immunization resulted in the production of specific antibodies that readily recognized the antigen. However, only one of the four antibody preparations, antibody 6148, elicited by a short peptide from the beta-chain (residues 61-73), reacts with native membrane glycoproteins as well as intact human lymphoblastoid cells in enzyme-linked immunosorbant assays. This antibody was found to react also with membrane glycoproteins solubilized by nonionic detergents from cells bearing a different HLA-DR specificity: therefore it is likely that the peptide responsible for eliciting antibody 6148 represents a common framework determinant of DR alloantigens that is accessible on the surface of lymphoblastoid cells. The ability of antibody 6148 to bind to intact cells was confirmed by indirect immunofluorescence and by fluorescein-activated cell sorter analysis. This antibody is also capable of mediating antibody-dependent cellular cytotoxicity as determined by a 51Cr-release assay.

  10. Evaluation of Vaccine-induced Antibody Responses: Impact of New Technologies

    Science.gov (United States)

    Zaccaro, Daniel J.; Wagener, Diane K.; Whisnant, Carol C.; Staats, Herman F.

    2013-01-01

    Host response to vaccination has historically been evaluated based on a change in antibody titer that compares the post-vaccination titer to the pre-vaccination titer. A four-fold or greater increase in antigen-specific antibody has been interpreted to indicate an increase in antibody production in response to vaccination. New technologies, such as the bead-based assays, provide investigators and clinicians with precise antibody levels (reported as concentration per mL) in ranges below and above those previously available through standard assays such as ELISA. Evaluations of bead assay data to determine host response to vaccination using fold change and absolute change, witha general linear models used to calculate adjusted statistics, present very different pictures of the antibody response when pre-vaccination antibody levels are low. Absolute changes in bead assay values, although not a standard computation, appears to more accurately reflect the host response to vaccination for those individuals with extremely low pre-vaccination antibody levels. Conversely, for these same individuals, fold change may be very high while post-vaccination antibodies do not achieve seroprotective levels. Absolute change provides an alternate method to characterize host response to vaccination, especially when pre-vaccination levels are very low, and may be useful in studies designed to determine associations between host genotypes and response to vaccination. PMID:23583812

  11. Prediction of the Hydrogen Peroxide-Induced Methionine Oxidation Propensity in Monoclonal Antibodies.

    Science.gov (United States)

    Agrawal, Neeraj J; Dykstra, Andrew; Yang, Jane; Yue, Hai; Nguyen, Xichdao; Kolvenbach, Carl; Angell, Nicolas

    2018-01-08

    Methionine oxidation in therapeutic antibodies can impact the product's stability, clinical efficacy, and safety and hence it is desirable to address the methionine oxidation liability during antibody discovery and development phase. Although the current experimental approaches can identify the oxidation-labile methionine residues, their application is limited mostly to the development phase. We demonstrate an in silico method that can be used to predict oxidation-labile residues based solely on the antibody sequence and structure information. Since antibody sequence information is available in the discovery phase, the in silico method can be applied very early on to identify the oxidation-labile methionine residues and subsequently address the oxidation liability. We believe that the in silico method for methionine oxidation liability assessment can aid in antibody discovery and development phase to address the liability in a more rational way. Copyright © 2018 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  12. Malaria-induced acquisition of antibodies to Plasmodium falciparum variant surface antigens

    DEFF Research Database (Denmark)

    Ofori, Michael F; Dodoo, Daniel; Staalsoe, Trine

    2002-01-01

    In areas of intense Plasmodium falciparum transmission, protective immunity is acquired during childhood in parallel with acquisition of agglutinating antibodies to parasite-encoded variant surface antigens (VSA) expressed on parasitized red blood cells. In a semi-immune child in such an area......, clinical disease is caused mainly by parasites expressing VSA not recognized by preexisting VSA-specific antibodies in that child. Such malaria episodes are known to cause an increase in agglutinating antibodies specifically recognizing VSA expressed by the parasite isolate causing the illness, whereas...... antibody responses to other parasite isolates are relatively unaffected. However, the detailed kinetics of this VSA antibody acquisition are unknown and hence were the aim of this study. We show that P. falciparum malaria in Ghanaian children generally caused a rapid and sustained increase in variant...

  13. Blocking antibodies induced by immunization with a hypoallergenic parvalbumin mutant reduce allergic symptoms in a mouse model of fish allergy

    OpenAIRE

    Freidl, Raphaela; Gstoettner, Antonia; Baranyi, Ulrike; Swoboda, Ines; Stolz, Frank; Focke-Tejkl, Margarete; Wekerle, Thomas; van Ree, Ronald; Valenta, Rudolf; Linhart, Birgit

    2016-01-01

    Background Fish is a frequent elicitor of severe IgE-mediated allergic reactions. Beside avoidance, there is currently no allergen-specific therapy available. Hypoallergenic variants of the major fish allergen, parvalbumin, for specific immunotherapy based on mutation of the 2 calcium-binding sites have been developed. Objectives This study sought to establish a mouse model of fish allergy resembling human disease and to investigate whether mouse and rabbit IgG antibodies induced by immunizat...

  14. Myostatin blockade with a fully human monoclonal antibody induces muscle hypertrophy and reverses muscle atrophy in young and aged mice.

    Science.gov (United States)

    Latres, Esther; Pangilinan, Jeffrey; Miloscio, Lawrence; Bauerlein, Roy; Na, Erqian; Potocky, Terra B; Huang, Ying; Eckersdorff, Mark; Rafique, Ashique; Mastaitis, Jason; Lin, Calvin; Murphy, Andrew J; Yancopoulos, George D; Gromada, Jesper; Stitt, Trevor

    2015-01-01

    Loss of skeletal muscle mass and function in humans is associated with significant morbidity and mortality. The role of myostatin as a key negative regulator of skeletal muscle mass and function has supported the concept that inactivation of myostatin could be a useful approach for treating muscle wasting diseases. We generated a myostatin monoclonal blocking antibody (REGN1033) and characterized its effects in vitro using surface plasmon resonance biacore and cell-based Smad2/3 signaling assays. REGN1033 was tested in mice for the ability to induce skeletal muscle hypertrophy and prevent atrophy induced by immobilization, hindlimb suspension, or dexamethasone. The effect of REGN1033 on exercise training was tested in aged mice. Messenger RNA sequencing, immunohistochemistry, and ex vivo force measurements were performed on skeletal muscle samples from REGN1033-treated mice. The human monoclonal antibody REGN1033 is a specific and potent myostatin antagonist. Chronic treatment of mice with REGN1033 increased muscle fiber size, muscle mass, and force production. REGN1033 prevented the loss of muscle mass induced by immobilization, glucocorticoid treatment, or hindlimb unweighting and increased the gain of muscle mass during recovery from pre-existing atrophy. In aged mice, REGN1033 increased muscle mass and strength and improved physical performance during treadmill exercise. We show that specific myostatin antagonism with the human antibody REGN1033 enhanced muscle mass and function in young and aged mice and had beneficial effects in models of skeletal muscle atrophy.

  15. Effect of anti-podoplanin antibody administration during lipopolysaccharide-induced lung injury in mice.

    Science.gov (United States)

    Lax, Sian; Rayes, Julie; Thickett, David R; Watson, Steve P

    2017-01-01

    Acute respiratory distress syndrome (ARDS) is a devastating pulmonary condition in the critically ill patient. A therapeutic intervention is yet to be found that can prevent progression to ARDS. We recently demonstrated that the interaction between podoplanin expressed on inflammatory alveolar macrophages (iAMs) and its endogenous ligand, platelet C-type lectin-like 2 (CLEC-2), protects against exaggerated lung inflammation during a mouse model of ARDS. In this study, we aim to investigate the therapeutic use of a crosslinking/activating anti-podoplanin antibody (α-PDPN, clone 8.1.1) during lipopolysaccharide (LPS)-induced lung inflammation in mice. Intravenous administration of α-PDPN was performed 6 hours after intratracheal LPS in wildtype, C57Bl/6 mice. Lung function decline was measured by pulse oximetry as well as markers of local inflammation including bronchoalveolar lavage neutrophilia and cytokine/chemokine expression. In parallel, alveolar macrophages were isolated and cultured in vitro from haematopoietic-specific podoplanin-deficient mice (Pdpn fl/fl VAV1cre + ) and floxed-only controls treated with or without LPS in the presence or absence of α-PDPN. Lung function decline as well as alveolar neutrophil recruitment was significantly decreased in mice treated with the crosslinking/activating α-PDPN in vivo. Furthermore, we demonstrate that, in vitro, activation of podoplanin on iAMs regulates their secretion of proinflammatory cytokines and chemokines. These data confirm the importance of the CLEC-2-podoplanin pathway during intratracheal (IT)-LPS and demonstrate the beneficial effect of targeting podoplanin during IT-LPS in mice possibly via modulation of local cytokine/chemokine expression. Moreover, these data suggest that podoplanin-targeted therapies may have a beneficial effect in patients at risk of developing ARDS.

  16. Antibody-mediated immunity to the obligate intracellular bacterial pathogen Coxiella burnetii is Fc receptor- and complement-independent

    Directory of Open Access Journals (Sweden)

    Heinzen Robert A

    2009-05-01

    Full Text Available Abstract Background The obligate intracellular bacterial pathogen Coxiella burnetii causes the zoonosis Q fever. The intracellular niche of C. burnetii has led to the assumption that cell-mediated immunity is the most important immune component for protection against this pathogen. However, passive immunization with immune serum can protect naïve animals from challenge with virulent C. burnetii, indicating a role for antibody (Ab in protection. The mechanism of this Ab-mediated protection is unknown. Therefore, we conducted a study to determine whether Fc receptors (FcR or complement contribute to Ab-mediated immunity (AMI to C. burnetii. Results Virulent C. burnetii infects and replicates within human dendritic cells (DC without inducing their maturation or activation. We investigated the effects of Ab opsonized C. burnetii on human monocyte-derived and murine bone marrow-derived DC. Infection of DC with Ab-opsonized C. burnetii resulted in increased expression of maturation markers and inflammatory cytokine production. Bacteria that had been incubated with naïve serum had minimal effect on DC, similar to virulent C. burnetii alone. The effect of Ab opsonized C. burnetii on DC was FcR dependent as evidenced by a reduced response of DC from FcR knockout (FcR k/o compared to C57Bl/6 (B6 mice. To address the potential role of FcR in Ab-mediated protection in vivo, we compared the response of passively immunized FcR k/o mice to the B6 controls. Interestingly, we found that FcR are not essential for AMI to C. burnetii in vivo. We subsequently examined the role of complement in AMI by passively immunizing and challenging several different strains of complement-deficient mice and found that AMI to C. burnetii is also complement-independent. Conclusion Despite our data showing FcR-dependent stimulation of DC in vitro, Ab-mediated immunity to C. burnetii in vivo is FcR-independent. We also found that passive immunity to this pathogen is independent of

  17. Broadly Neutralizing Hemagglutinin Stalk-Specific Antibodies Induce Potent Phagocytosis of Immune Complexes by Neutrophils in an Fc-Dependent Manner.

    Science.gov (United States)

    Mullarkey, Caitlin E; Bailey, Mark J; Golubeva, Diana A; Tan, Gene S; Nachbagauer, Raffael; He, Wenqian; Novakowski, Kyle E; Bowdish, Dawn M; Miller, Matthew S; Palese, Peter

    2016-10-04

    Broadly neutralizing antibodies that recognize the conserved hemagglutinin (HA) stalk have emerged as exciting new biotherapeutic tools to combat seasonal and pandemic influenza viruses. Our general understanding of the mechanisms by which stalk-specific antibodies achieve protection is rapidly evolving. It has recently been demonstrated that broadly neutralizing HA stalk-specific IgG antibodies require Fc-Fcγ receptor (FcγR) interactions for optimal protection in vivo Here we examine the neutrophil effector functions induced by stalk-specific antibodies. As the most abundant subset of blood leukocytes, neutrophils represent a critical innate effector cell population and serve an instrumental role in orchestrating downstream adaptive responses to influenza virus infection. Yet, the interplay of HA stalk-specific IgG, Fc-FcγR engagement, and neutrophils has remained largely uncharacterized. Using an in vitro assay to detect the production of reactive oxygen species (ROS), we show that human and mouse monoclonal HA stalk-specific IgG antibodies are able to induce the production of ROS by neutrophils, while HA head-specific antibodies do not. Furthermore, our results indicate that the production of ROS is dependent on Fc receptor (FcR) engagement and phagocytosis. We went on to assess the ability of monoclonal HA stalk-specific IgA antibodies to induce ROS. Consistent with our findings for monoclonal IgGs, only HA stalk-specific IgA antibodies elicited ROS production by neutrophils. This induction is dependent on the engagement of FcαR1. Taken together, our findings describe a novel FcR-dependent effector function induced by HA stalk-specific IgG and IgA antibodies, and importantly, our studies shed light on the mechanisms by which HA stalk-specific antibodies achieve protection. The present study provides evidence that broadly neutralizing HA stalk-specific antibodies induce downstream Fc-mediated neutrophil effector functions. In addition to their ability to

  18. Anti-IL-2 receptor antibody decreases cytokine-induced apoptosis of human renal tubular epithelial cells (TEC).

    Science.gov (United States)

    Wang, Shuang; Zhang, Zhu-Xu; Yin, Ziqin; Liu, Weihua; Garcia, Bertha; Huang, Xuyan; Acott, Philip; Jevnikar, Anthony M

    2011-07-01

    Transplant rejection is mediated by T-cell activation which is modulated by interleukin-2 (IL-2) binding to IL-2R (CD25). Monoclonal anti-IL-2 receptor antibody is used in renal transplantation to reduce rejection. Interestingly, proximal tubular epithelial cells (TEC) express CD25, similar to T cells. We have demonstrated that IL-2 induces murine TEC apoptosis through down-regulation of the caspase-8 inhibitor protein c-FLIP. Anti-CD25 antibody may be useful clinically to limit renal injury, but this has not been tested in human TEC. Human PT-2 TEC were isolated and cloned from the urine of transplant patients. Apoptosis was determined by FACS with Annexin-V FITC. Protein expression was studied using western blot, and mRNA levels by quantitative real-time (PR-PCR). We demonstrated that the morphology of a human kidney cell line (PT-2) cloned from urine was consistent with proximal TEC and expresses alkaline phosphatase, cytokeratin, vimentin, CD13, CD26, and low levels of E-cadherin. Basal IL-2 receptor (CD25) was up-regulated by IL-2/IFN-γ stimulation, and cytokine exposure induced apoptosis in a dose-dependent manner. Apoptosis with IL-2/IFN-γ was associated with increased caspase-8 activity and decreased endogenous caspase-8 inhibitor c-FLIP mRNA and protein expression. IL-2/IFN-γ-induced apoptosis could be blocked by pre-treatment of PT-2 with anti IL-2R antibody (basiliximab) but not control IgG antibody. These data demonstrate for the first time in human TEC that IL-2 and IFN-γ can induce TEC apoptosis which can be blocked by CD25 blockade antibody. These data suggest that anti-CD25 mAb might similarly attenuate inflammation-induced TEC injury in vivo. Kidney-expressed CD25 may represent a clinically important new target for attenuating early inflammatory injury in donor kidneys and preserving renal function during anti-rejection therapy.

  19. Comparative opsonic activity for Steptococcus mutans in oral fluids, and phagocytic activity of blood, crevicular, and salivary polymorphonuclear leucocytes in rhesus monkeys.

    Science.gov (United States)

    Scully, C M

    1980-01-01

    The opsonic activity for Streptococcus mutans was assayed in serum, gingival crevicular fluid, parotid saliva and mixed saliva from rhesus monkeys immunized against dental caries with a vaccine of Streptococcus mutans in Freund's incomplete adjuvant. The phagocytic activities of polymorphonuclear leucocytes from the blood and gingival crevice were compared, and the effects of gingival crevicular fluid and mixed saliva on blood polymorphonuclear leucocyte viability and phagocytic activity were assessed. Heat-stable opsonic activity was detected in sera, crevicular fluid, and mixed saliva of immunized animals. Polymorphonuclear leucocytes from the gingival crevice and saliva retained viability, although this was lower than in cells from blood. Exposure of blood polymorphonuclear leucocytes to crevicular fluid or mixed saliva for 30 min resulted in no loss of cell viability or phagocytic activity, but saliva was cytotoxic on prolonged exposure. These results support the hypothesis that the opsonization and phagocytosis of cariogenic bacteria might be a mechanism involved in the immunological protection against dental caries.

  20. Coombs Antiglobulin Test Using Brucella abortus 99 as Antigen To Detect Incomplete Antibodies Induced by B. abortus RB51 Vaccine in Cattle

    OpenAIRE

    Ciuchini, Franco; Adone, Rosanna; Pasquali, Paolo

    2002-01-01

    This study showed that vaccination of cattle with Brucella abortus rough strain RB51 induces incomplete antibodies that can be detectable by a Coombs antiglobulin test using the B. abortus 99 smooth strain.

  1. Guillain-Barré syndrome- and Miller Fisher syndrome-associated Campylobacter jejuni lipopolysaccharides induce anti-GM1 and anti-GQ1b Antibodies in rabbits.

    NARCIS (Netherlands)

    M.A. de Klerk; H.P. Endtz (Hubert); B.C. Jacobs (Bart); J.D. Laman (Jon); F.G.A. van der Meché (Frans); P.A. van Doorn (Pieter); C.W. Ang (Wim)

    2001-01-01

    textabstractCampylobacter jejuni infections are thought to induce antiganglioside antibodies in patients with Guillain-Barre syndrome (GBS) and Miller Fisher syndrome (MFS) by molecular mimicry between C. jejuni lipopolysaccharides (LPS) and gangliosides. We used

  2. Recombinant outer membrane vesicles carrying Chlamydia muridarum HtrA induce antibodies that neutralize chlamydial infection in vitro

    Science.gov (United States)

    Bartolini, Erika; Ianni, Elvira; Frigimelica, Elisabetta; Petracca, Roberto; Galli, Giuliano; Berlanda Scorza, Francesco; Norais, Nathalie; Laera, Donatello; Giusti, Fabiola; Pierleoni, Andrea; Donati, Manuela; Cevenini, Roberto; Finco, Oretta; Grandi, Guido; Grifantini, Renata

    2013-01-01

    Background Outer membrane vesicles (OMVs) are spheroid particles released by all Gram-negative bacteria as a result of the budding out of the outer membrane. Since they carry many of the bacterial surface-associated proteins and feature a potent built-in adjuvanticity, OMVs are being utilized as vaccines, some of which commercially available. Recently, methods for manipulating the protein content of OMVs have been proposed, thus making OMVs a promising platform for recombinant, multivalent vaccines development. Methods Chlamydia muridarum DO serine protease HtrA, an antigen which stimulates strong humoral and cellular responses in mice and humans, was expressed in Escherichia coli fused to the OmpA leader sequence to deliver it to the OMV compartment. Purified OMVs carrying HtrA (CM rHtrA-OMV) were analyzed for their capacity to induce antibodies capable of neutralizing Chlamydia infection of LLC-MK2 cells in vitro. Results CM rHtrA-OMV immunization in mice induced antibodies that neutralize Chlamydial invasion as judged by an in vitro infectivity assay. This was remarkably different from what observed with an enzymatically functional recombinant HtrA expressed in, and purified from the E. coli cytoplasm (CM rHtrA). The difference in functionality between anti-CM rHtrA and anti-CM rHtrA-OMV antibodies was associated to a different pattern of protein epitopes recognition. The epitope recognition profile of anti-CM HtrA-OMV antibodies was similar to that induced in mice during Chlamydial infection. Conclusions When expressed in OMVs HtrA appears to assume a conformation similar to the native one and this results in the elicitation of functional immune responses. These data further support the potentiality of OMVs as vaccine platform. PMID:24009891

  3. Dengue E Protein Domain III-Based DNA Immunisation Induces Strong Antibody Responses to All Four Viral Serotypes.

    Directory of Open Access Journals (Sweden)

    Monica Poggianella

    Full Text Available Dengue virus (DENV infection is a major emerging disease widely distributed throughout the tropical and subtropical regions of the world affecting several millions of people. Despite constants efforts, no specific treatment or effective vaccine is yet available. Here we show a novel design of a DNA immunisation strategy that resulted in the induction of strong antibody responses with high neutralisation titres in mice against all four viral serotypes. The immunogenic molecule is an engineered version of the domain III (DIII of the virus E protein fused to the dimerising CH3 domain of the IgG immunoglobulin H chain. The DIII sequences were also codon-optimised for expression in mammalian cells. While DIII alone is very poorly secreted, the codon-optimised fusion protein is rightly expressed, folded and secreted at high levels, thus inducing strong antibody responses. Mice were immunised using gene-gun technology, an efficient way of intradermal delivery of the plasmid DNA, and the vaccine was able to induce neutralising titres against all serotypes. Additionally, all sera showed reactivity to a recombinant DIII version and the recombinant E protein produced and secreted from mammalian cells in a mono-biotinylated form when tested in a conformational ELISA. Sera were also highly reactive to infective viral particles in a virus-capture ELISA and specific for each serotype as revealed by the low cross-reactive and cross-neutralising activities. The serotype specific sera did not induce antibody dependent enhancement of infection (ADE in non-homologous virus serotypes. A tetravalent immunisation protocol in mice showed induction of neutralising antibodies against all four dengue serotypes as well.

  4. Immunization with recombinantly expressed glycan antigens from Schistosoma mansoni induces glycan-specific antibodies against the parasite.

    Science.gov (United States)

    Prasanphanich, Nina Salinger; Luyai, Anthony E; Song, Xuezheng; Heimburg-Molinaro, Jamie; Mandalasi, Msano; Mickum, Megan; Smith, David F; Nyame, A Kwame; Cummings, Richard D

    2014-07-01

    Schistosomiasis caused by infection with parasitic helminths of Schistosoma spp. is a major global health problem due to inadequate treatment and lack of a vaccine. The immune response to schistosomes includes glycan antigens, which could be valuable diagnostic markers and vaccine targets. However, no precedent exists for how to design vaccines targeting eukaryotic glycoconjugates. The di- and tri-saccharide motifs LacdiNAc (GalNAcβ1,4GlcNAc; LDN) and fucosylated LacdiNAc (GalNAcβ1,4(Fucα1-3)GlcNAc; LDNF) are the basis for several important schistosome glycan antigens. They occur in monomeric form or as repeating units (poly-LDNF) and as part of a variety of different glycoconjugates. Because chemical synthesis and conjugation of such antigens is exceedingly difficult, we sought to develop a recombinant expression system for parasite glycans. We hypothesized that presentation of parasite glycans on the cell surface would induce glycan-specific antibodies. We generated Chinese hamster ovary (CHO) Lec8 cell lines expressing poly-LDN (L8-GT) and poly-LDNF (L8-GTFT) abundantly on their membrane glycoproteins. Sera from Schistosoma mansoni-infected mice were highly cross-reactive with the cells and with cell-surface N-glycans. Immunizing mice with L8-GT and L8-GTFT cells induced glycan-specific antibodies. The L8-GTFT cells induced a sustained booster response, with antibodies that bound to S. mansoni lysates and recapitulated the exquisite specificity of the anti-parasite response for particular presentations of LDNF antigen. In summary, this recombinant expression system promotes successful generation of antibodies to the glycans of S. mansoni, and it can be adapted to study the role of glycan antigens and anti-glycan immune responses in many other infections and pathologies. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Zika Virus-Induced Antibody Response Enhances Dengue Virus Serotype 2 Replication In Vitro.

    Science.gov (United States)

    Kawiecki, Anna B; Christofferson, Rebecca C

    2016-11-01

    Zika virus has emerged in the Americas, where dengue virus is endemic. Among the 4 serotypes of dengue virus, antibody-dependent enhancement is thought to enhance viral replication and disease severity. Reports suggest that anti-dengue virus antibody may enhance Zika virus replication. We investigated whether Zika virus antibodies enhance dengue virus replication, by exposing C57Bl/6 mice to Zika virus. Polyclonal serum was verified for strong Zika virus-neutralizing, dengue virus-subneutralizing capacity. Then we determined the enhancement capabilities of Zika virus-immune serum for dengue virus in vitro. We showed that Zika virus antibodies have the ability to enhance dengue virus infections, which is important, because in many Zika virus-affected areas, dengue virus is expected to remain endemic. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  6. Novel adenoviral vector induces T-cell responses despite anti-adenoviral neutralizing antibodies in colorectal cancer patients.

    Science.gov (United States)

    Morse, Michael A; Chaudhry, Arvind; Gabitzsch, Elizabeth S; Hobeika, Amy C; Osada, Takuya; Clay, Timothy M; Amalfitano, Andrea; Burnett, Bruce K; Devi, Gayathri R; Hsu, David S; Xu, Younong; Balcaitis, Stephanie; Dua, Rajesh; Nguyen, Susan; Balint, Joseph P; Jones, Frank R; Lyerly, H Kim

    2013-08-01

    First-generation, E1-deleted adenovirus subtype 5 (Ad5)-based vectors, although promising platforms for use as cancer vaccines, are impeded in activity by naturally occurring or induced Ad-specific neutralizing antibodies. Ad5-based vectors with deletions of the E1 and the E2b regions (Ad5 [E1-, E2b-]), the latter encoding the DNA polymerase and the pre-terminal protein, by virtue of diminished late phase viral protein expression, were hypothesized to avoid immunological clearance and induce more potent immune responses against the encoded tumor antigen transgene in Ad-immune hosts. Indeed, multiple homologous immunizations with Ad5 [E1-, E2b-]-CEA(6D), encoding the tumor antigen carcinoembryonic antigen (CEA), induced CEA-specific cell-mediated immune (CMI) responses with antitumor activity in mice despite the presence of preexisting or induced Ad5-neutralizing antibody. In the present phase I/II study, cohorts of patients with advanced colorectal cancer were immunized with escalating doses of Ad5 [E1-, E2b-]-CEA(6D). CEA-specific CMI responses were observed despite the presence of preexisting Ad5 immunity in a majority (61.3 %) of patients. Importantly, there was minimal toxicity, and overall patient survival (48 % at 12 months) was similar regardless of preexisting Ad5 neutralizing antibody titers. The results demonstrate that, in cancer patients, the novel Ad5 [E1-, E2b-] gene delivery platform generates significant CMI responses to the tumor antigen CEA in the setting of both naturally acquired and immunization-induced Ad5-specific immunity.

  7. Quorum-sensing regulator RhlR but not its autoinducer RhlI enables Pseudomonas to evade opsonization.

    Science.gov (United States)

    Haller, Samantha; Franchet, Adrien; Hakkim, Abdul; Chen, Jing; Drenkard, Eliana; Yu, Shen; Schirmeier, Stefanie; Li, Zi; Martins, Nelson; Ausubel, Frederick M; Liégeois, Samuel; Ferrandon, Dominique

    2018-03-09

    When Drosophila melanogaster feeds on Pseudomonas aeruginosa , some bacteria cross the intestinal barrier and eventually proliferate in the hemocoel. This process is limited by hemocytes through phagocytosis. P. aeruginosa requires the quorum-sensing regulator RhlR to elude the cellular immune response of the fly. RhlI synthesizes the autoinducer signal that activates RhlR. Here, we show that rhlI mutants are unexpectedly more virulent than rhlR mutants, both in fly and in nematode intestinal infection models, suggesting that RhlR has RhlI-independent functions. We also report that RhlR protects P. aeruginosa from opsonization mediated by the Drosophila thioester-containing protein 4 (Tep4). RhlR mutant bacteria show higher levels of Tep4- mediated opsonization, as compared to rhlI mutants, which prevents lethal bacteremia in the Drosophila hemocoel. In contrast, in a septic model of infection, in which bacteria are introduced directly into the hemocoel, Tep4 mutant flies are more resistant to wild-type P. aeruginosa, but not to the rhlR mutant. Thus, depending on the infection route, the Tep4 opsonin can either be protective or detrimental to host defense. © 2018 The Authors.

  8. Hepatitis C Virus E1 and E2 Proteins Used as Separate Immunogens Induce Neutralizing Antibodies with Additive Properties.

    Directory of Open Access Journals (Sweden)

    Elodie Beaumont

    Full Text Available Various strategies involving the use of hepatitis C virus (HCV E1 and E2 envelope glycoproteins as immunogens have been developed for prophylactic vaccination against HCV. However, the ideal mode of processing and presenting these immunogens for effective vaccination has yet to be determined. We used our recently described vaccine candidate based on full-length HCV E1 or E2 glycoproteins fused to the heterologous hepatitis B virus S envelope protein to compare the use of the E1 and E2 proteins as separate immunogens with their use as the E1E2 heterodimer, in terms of immunogenetic potential and the capacity to induce neutralizing antibodies. The specific anti-E1 and anti-E2 antibody responses induced in animals immunized with vaccine particles harboring the heterodimer were profoundly impaired with respect to those in animals immunized with particles harboring E1 and E2 separately. Moreover, the anti-E1 and anti-E2 antibodies had additive neutralizing properties that increase the cross-neutralization of heterologous strains of various HCV genotypes, highlighting the importance of including both E1 and E2 in the vaccine for an effective vaccination strategy. Our study has important implications for the optimization of HCV vaccination strategies based on HCV envelope proteins, regardless of the platform used to present these proteins to the immune system.

  9. Effects of inhaled fine dust on lung tissue changes and antibody response induced by spores of opportunistic fungi in goats.

    Science.gov (United States)

    Purdy, Charles W; Layton, Robert C; Straus, David C; Ayers, J R

    2008-04-01

    To investigate the effects of sterile fine dust aerosol inhalation on antibody responses and lung tissue changes induced by Mucor ramosissimus or Trichoderma viride spores following intratracheal inoculation in goats. 36 weanling Boer-Spanish goats. 6 goats were allocated to each of 2 M ramosissimus-inoculated groups, 2 T viride-inoculated groups, and 2 control (tent or pen) groups. One of each pair of sporetreated groups and the tent control group were exposed 7 times to sterilized fine feedyard dust (mean+/-SD particle diameter, dust. Goats received an IV challenge with equine RBCs to assess antibody responses to foreign antigens. Postmortem examinations were performed at study completion (day 68) to evaluate lung tissue lesions. 5 of 7 deaths occurred between days 18 and 45 and were attributed to fine dust exposures prior to fungal treatments. Fine dust inhalation induced similar lung lesions and precipitating antibodies among spore-treated goats. Following spore inoculations, dust-exposed goats had significantly more spores per gram of consolidated lung tissue than did their nonexposed counterparts. Fine dust inhalation appeared to decrease the ability of goats to successfully clear fungal spores from the lungs following intratracheal inoculation.

  10. Broadly Neutralizing Hemagglutinin Stalk-Specific Antibodies Induce Potent Phagocytosis of Immune Complexes by Neutrophils in an Fc-Dependent Manner

    Directory of Open Access Journals (Sweden)

    Caitlin E. Mullarkey

    2016-10-01

    Full Text Available Broadly neutralizing antibodies that recognize the conserved hemagglutinin (HA stalk have emerged as exciting new biotherapeutic tools to combat seasonal and pandemic influenza viruses. Our general understanding of the mechanisms by which stalk-specific antibodies achieve protection is rapidly evolving. It has recently been demonstrated that broadly neutralizing HA stalk-specific IgG antibodies require Fc-Fcγ receptor (FcγR interactions for optimal protection in vivo. Here we examine the neutrophil effector functions induced by stalk-specific antibodies. As the most abundant subset of blood leukocytes, neutrophils represent a critical innate effector cell population and serve an instrumental role in orchestrating downstream adaptive responses to influenza virus infection. Yet, the interplay of HA stalk-specific IgG, Fc-FcγR engagement, and neutrophils has remained largely uncharacterized. Using an in vitro assay to detect the production of reactive oxygen species (ROS, we show that human and mouse monoclonal HA stalk-specific IgG antibodies are able to induce the production of ROS by neutrophils, while HA head-specific antibodies do not. Furthermore, our results indicate that the production of ROS is dependent on Fc receptor (FcR engagement and phagocytosis. We went on to assess the ability of monoclonal HA stalk-specific IgA antibodies to induce ROS. Consistent with our findings for monoclonal IgGs, only HA stalk-specific IgA antibodies elicited ROS production by neutrophils. This induction is dependent on the engagement of FcαR1. Taken together, our findings describe a novel FcR-dependent effector function induced by HA stalk-specific IgG and IgA antibodies, and importantly, our studies shed light on the mechanisms by which HA stalk-specific antibodies achieve protection.

  11. Monitoring UV-induced signalling pathways in an ex vivo skin organ culture model using phospho-antibody array.

    Science.gov (United States)

    Lenain, Christelle; Gamboa, Bastien; Perrin, Agnes; Séraïdaris, Alexia; Bertino, Béatrice; Rival, Yves; Bernardi, Mathieu; Piwnica, David; Méhul, Bruno

    2017-09-08

    We investigated UV-induced signalling in an ex vivo skin organ culture model using phospho-antibody array. Phosphorylation modulations were analysed in time-course experiments following exposure to solar-simulated UV and validated by Western blot analyses. We found that UV induced P-p38 and its substrates, P-ERK1/2 and P-AKT, which were previously shown to be upregulated by UV in cultured keratinocytes and in vivo human skin. This indicates that phospho-antibody array applied to ex vivo skin organ culture is a relevant experimental system to investigate signalling events following perturbations. As the identified proteins are components of pathways implicated in skin tumorigenesis, UV-exposed skin organ culture model could be used to investigate the effect on these pathways of NMSC cancer drug candidates. In addition, we found that phospho-HCK is induced upon UV exposure, producing a new candidate for future studies investigating its role in the skin response to UV and UV-induced carcinogenesis. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Antibodies against keratinocyte antigens other than desmogleins 1 and 3 can induce pemphigus vulgaris–like lesions

    Science.gov (United States)

    Nguyen, Vu Thuong; Ndoye, Assane; Shultz, Leonard D.; Pittelkow, Mark R.; Grando, Sergei A.

    2000-01-01

    Pemphigus is an autoimmune disease of skin adhesion associated with autoantibodies against a number of keratinocyte antigens, such as the adhesion molecules desmoglein (Dsg) 1 and 3 and acetylcholine receptors. The notion that anti-Dsg antibodies alone are responsible for blisters in patients with pemphigus vulgaris (PV) stems from the ability of rDsg1 and rDsg3 to absorb antibodies that cause PV-like skin blisters in neonatal mice. Here, we demonstrate that PV IgGs eluted from rDsg1-Ig-His and rDsg3-Ig-His show similar antigenic profiles, including the 38-, 43-, 115-, and 190-kDa keratinocyte proteins and a non–Dsg 3 130-kDa polypeptide present in keratinocytes from Dsg 3 knockout mouse. We injected into Dsg 3–lacking mice the PV IgGs that did not cross-react with the 160-kDa Dsg 1 or its 45-kDa immunoreactive fragment and that showed no reactivity with recombinant Dsg 1. We used both the Dsg3null mice with a targeted mutation of the Dsg3 gene and the “balding” Dsg3bal/Dsg3bal mice that carry a spontaneous null mutation in Dsg3. These PV IgGs caused gross skin blisters with PV-like suprabasal acantholysis and stained perilesional epidermis in a fishnet-like pattern, indicating that the PV phenotype can be induced without anti–Dsg 3 antibody. The anti–Dsg 1 antibody also was not required, as its presence in PV IgG does not alter the PV-like phenotype in skin organ cultures and because pemphigus foliaceus IgGs produce a distinct phenotype in Dsg3null mice. Therefore, mucocutaneous lesions in PV patients could be caused by non-Dsg antibodies. PMID:11120754

  13. Antibody-based inhibition of circulating DLK1 protects from estrogen deficiency-induced bone loss in mice

    DEFF Research Database (Denmark)

    Figeac, Florence; Andersen, Ditte C.; Nipper Nielsen, Casper A.

    2018-01-01

    /TV) and inhibition of bone resorption. No significant changes were observed in total fat mass or in the number of bone marrow adipocytes. These results support the potential use of anti-DLK1 antibody therapy as a novel intervention to protect from E deficiency associated bone loss....... deficiency-associated bone loss in mice. Thus, we generated mouse monoclonal anti-mouse DLK1 antibodies (MAb DLK1) that enabled us to reduce and also quantitate the levels of bioavailable serum DLK1 in vivo. Ovariectomized (ovx) mice were injected intraperitoneally twice weekly with MAb DLK1 over a period...... of one month. DEXA-, microCT scanning, and bone histomorphometric analyses were performed. Compared to controls, MAb DLK1 treated ovx mice were protected against ovx-induced bone loss, as revealed by significantly increased total bone mass (BMD) due to increased trabecular bone volume fraction (BV...

  14. Vaccination of dogs with Trypanosoma rangeli induces antibodies against Trypanosoma cruzi in a rural area of Córdoba, Argentina.

    Science.gov (United States)

    Basso, Beatriz; Marini, Vanina; Gauna, Diego; Frias, Maria

    2016-04-01

    Dogs play a major role in the domestic cycle of Trypanosoma cruzi, acting as reservoirs. In a previous work we have developed a model of vaccination of dogs in captivity with nonpathogenic Trypanosoma rangeli epimastigotes, resulting in the production of protective antibodies against T. cruzi, with dramatic decrease of parasitaemia upon challenge with 100,000 virulent forms of this parasite. The aim of this work was to evaluate the immunogenicity of this vaccine in dogs living in a rural area. Domestic dogs, free from T. cruzi infection, received three immunisations with fixed T. rangeli epimastigotes. Dogs were not challenged with T. cruzi, but they were left in their environment. This immunisation induced antibodies against T. cruzi for more than three years in dogs in their natural habitat, while control dogs remained serologically negative.

  15. Blocking antibodies induced by immunization with a hypoallergenic parvalbumin mutant reduce allergic symptoms in a mouse model of fish allergy.

    Science.gov (United States)

    Freidl, Raphaela; Gstoettner, Antonia; Baranyi, Ulrike; Swoboda, Ines; Stolz, Frank; Focke-Tejkl, Margarete; Wekerle, Thomas; van Ree, Ronald; Valenta, Rudolf; Linhart, Birgit

    2017-06-01

    Fish is a frequent elicitor of severe IgE-mediated allergic reactions. Beside avoidance, there is currently no allergen-specific therapy available. Hypoallergenic variants of the major fish allergen, parvalbumin, for specific immunotherapy based on mutation of the 2 calcium-binding sites have been developed. This study sought to establish a mouse model of fish allergy resembling human disease and to investigate whether mouse and rabbit IgG antibodies induced by immunization with a hypoallergenic mutant of the major carp allergen protect against allergic symptoms in sensitized mice. C3H/HeJ mice were sensitized with recombinant wildtype Cyp c 1 or carp extract by intragastric gavage. Antibody, cellular immune responses, and epitope specificity in sensitized mice were investigated by ELISA, rat basophil leukemia assay, T-cell proliferation experiments using recombinant wildtype Cyp c 1, and overlapping peptides spanning the Cyp c 1 sequence. Anti-hypoallergenic Cyp c 1 mutant mouse and rabbit sera were tested for their ability to inhibit IgE recognition of Cyp c 1, Cyp c 1-specific basophil degranulation, and Cyp c 1-induced allergic symptoms in the mouse model. A mouse model of fish allergy mimicking human disease regarding IgE epitope recognition and symptoms as close as possible was established. Administration of antisera generated in mice and rabbits by immunization with a hypoallergenic Cyp c 1 mutant inhibited IgE binding to Cyp c 1, Cyp c 1-induced basophil degranulation, and allergic symptoms caused by allergen challenge in sensitized mice. Antibodies induced by immunization with a hypoallergenic Cyp c 1 mutant protect against allergic reactions in a murine model of fish allergy. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Human agonistic TRAIL receptor antibodies Mapatumumab and Lexatumumab induce apoptosis in malignant mesothelioma and act synergistically with cisplatin

    Directory of Open Access Journals (Sweden)

    Felley-Bosco Emanuela

    2007-10-01

    Full Text Available Abstract Background The incidence of malignant pleural mesothelioma (MPM is associated with exposure to asbestos, and projections suggest that the yearly number of deaths in Western Europe due to MPM will increase until 2020. Despite progress in chemo- and in multimodality therapy, MPM remains a disease with a poor prognosis. Inducing apoptosis by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL or agonistic monoclonal antibodies which target TRAIL-receptor 1 (TRAIL-R1 or TRAIL-R2 has been thought to be a promising cancer therapy. Results We have compared the sensitivity of 13 MPM cell lines or primary cultures to TRAIL and two fully human agonistic monoclonal antibodies directed to TRAIL-R1 (Mapatumumab and TRAIL-R2 (Lexatumumab and examined sensitization of the MPM cell lines to cisplatin-induced by the TRAIL-receptor antibodies. We found that sensitivity of MPM cells to TRAIL, Mapatumumab and Lexatumumab varies largely and is independent of TRAIL-receptor expression. TRAIL-R2 contributes more than TRAIL-R1 to death-receptor mediated apoptosis in MPM cells that express both receptors. The combination of cisplatin with Mapatumumab or Lexatumumab synergistically inhibited the cell growth and enhanced apoptotic death. Furthermore, pre-treatment with cisplatin followed by Mapatumumab or Lexatumumab resulted in significant higher cytotoxic effects as compared to the reverse sequence. Combination-induced cell growth inhibition was significantly abrogated by pre-treatment of the cells with the antioxidant N-acetylcysteine. Conclusion Our results suggest that the sequential administration of cisplatin followed by Mapatumumab or Lexatumumab deserves investigation in the treatment of patients with MPM.

  17. A synthetic peptide derived from domain III envelope glycoprotein of Dengue virus induces neutralizing antibody.

    Science.gov (United States)

    Mary, J Asnet; Jittmittraphap, Akanitt; Chattanadee, Siriporn; Leaungwutiwong, Pornsawan; Shenbagarathai, R

    2018-02-01

    Dengue virus (DENV) is an arthropod-borne human pathogen that represents a severe public health threat in both endemic and non-endemic regions. So far, there is no licensed vaccine or specific drugs available for dengue fever. A fifteen-amino-acid-long peptide that includes the NGR motif was chemically synthesized and conjugated with keyhole limpet hemocyanin. A standard immunization protocol was followed for the production of polyclonal antibodies by immunizing rabbits against the synthetic peptide. The immune response elicited high-titer polyclonal antibodies with the reactivity of the anti-peptide antibody against both synthetic peptide and four serotypes of DENV confirmed by DOT-ELISA. Neutralizing activity of anti-peptide antibody was found to be cross-reactive and effective resulting in 60% reduction of infectivity at 1:200 dilution in all four serotypes of DENV. Our findings have the potential to further improve our understanding of virus-host interactions and provide new insights into neutralizing antibodies and could also be used as a drug target.

  18. Antibody-dependent cellular inhibition is associated with reduced risk against febrile malaria in a longitudinal cohort study involving Ghanaian children

    DEFF Research Database (Denmark)

    Tiendrebeogo, Regis W; Adu, Bright; Singh, Susheel K

    2015-01-01

    The antibody-dependent respiratory burst and opsonic phagocytosis assays have been associated with protection against malaria; however, other mechanisms may also be involved. The antibody-dependent cellular inhibition (ADCI) assay is yet to be correlated with protection in longitudinal cohort stu...... of the ADCI assay as a correlate of protection to guide malaria vaccine studies.......The antibody-dependent respiratory burst and opsonic phagocytosis assays have been associated with protection against malaria; however, other mechanisms may also be involved. The antibody-dependent cellular inhibition (ADCI) assay is yet to be correlated with protection in longitudinal cohort...... studies (LCS). We investigated the relationship between ADCI activity of immunoglobulin G before malaria season and risk of malaria in a LCS involving Ghanaian children. High ADCI activity was significantly associated with reduced risk against malaria. Findings here suggest a potential usefulness...

  19. Detection of antibodies to single-stranded DNA in naturally acquired and experimentally induced viral hepatitis

    Energy Technology Data Exchange (ETDEWEB)

    Gust, I.D.; Feinstone, S.M.; Purcell, R.H.; Alter, H.J.

    1980-01-01

    A sensitive ''Farr'' assay, utilizing /sup 125/I-labelled DNA was developed for detecting antibody to single-stranded DNA (anti-ssDNA). The test was shown to be specific and as sensitive as assays using /sup 14/C-labelled DNA, for the detection of antibody in patients with connective tissue diseases. Groups of sera from patients with naturally acquired viral hepatitis and experimentally infected chimpanzees were tested for anti-ssDNA by the /sup 125/I assay and by counterimmunoelectrophoresis (CIEP). No consistent pattern was observed with either technique, indicating the elevated levels of this antibody are not as reliable markers of parenchymal liver damage as had been previously suggested.

  20. Parasite Specific Antibody Increase Induced by an Episode of Acute P. falciparum Uncomplicated Malaria.

    Directory of Open Access Journals (Sweden)

    Mark Kaddumukasa

    Full Text Available There is no approved vaccine for malaria, and precisely how human antibody responses to malaria parasite components and potential vaccine molecules are developed and maintained remains poorly defined. In this study, antibody anamnestic or memory response elicited by a single episode of P. falciparum infection was investigated.This study involved 362 malaria patients aged between 6 months to 60 years, of whom 19% were early-diagnosed people living with HIV/AIDS (PLWHA. On the day malaria was diagnosed and 42 days later, blood specimens were collected. Parasite density, CD4+ cells, and antibodies specific to synthetic peptides representing antigenic regions of the P. falciparum proteins GLURP, MSP3 and HRPII were measured.On the day of malaria diagnosis, Immunoglobulin (IgG antibodies against GLURP, MSP3 and HRP II peptides were present in the blood of 75%, 41% and 60% of patients, respectively. 42 days later, the majority of patients had boosted their serum IgG antibody more than 1.2 fold. The increase in level of IgG antibody against the peptides was not affected by parasite density at diagnosis. The median CD4+ cell counts of PLWHAs and HIV negative individuals were not statistically different, and median post-infection increases in anti-peptide IgG were similar in both groups of patients.In the majority (70% of individuals, an infection of P. falciparum elicits at least 20% increase in level of anti-parasite IgG. This boost in anti-P. falciparum IgG is not affected by parasite density on the day of malaria diagnosis, or by HIV status.

  1. Comparison of infection-neutralizing and -enhancing antibody balance induced by two distinct genotype strains of dengue virus type 1 or 3 DNA vaccines in mice.

    Science.gov (United States)

    Sjatha, Fithriyah; Takizawa, Yamato; Kotaki, Tomohiro; Yamanaka, Atsushi; Konishi, Eiji

    2013-11-01

    Dengue viruses have spread throughout tropical and subtropical countries, and vaccine development is urgently needed. However, one concern is that induction of insufficient levels of neutralizing antibodies in vaccines may increase disease severity because of a hypothetical mechanism termed antibody-dependent enhancement of infection. This study used two distinct genotype strains of dengue virus types 1 and 3 (DENV1 and DENV3, respectively) to compare antibody responses in a mouse-DNA vaccine model. As expected, a conventional neutralization test using Vero cells showed higher antibody titers in homologous rather than heterologous combinations of genotype strains used for mouse immunization and the neutralization test, for each of DENV1 and DENV3. However, our assay system using K562 cells to measure the balance of neutralizing and enhancing antibodies indicated that Vero cell-neutralizing antibody titers did not always correlate with enhancing activities observed at subneutralizing doses. Rather, induction of enhancing activities depended on the genotype strain used for mouse immunization. The genotype/strain difference also affected IgG subclass profiles and potentially the composition of antibody species induced in mice. This study suggests that enhancing activities of dengue virus-induced neutralizing antibodies may vary according to the genotype and has implications for vaccine antigen development. Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  2. Vaccination with a Recombinant H7 Hemagglutinin-Based Influenza Virus Vaccine Induces Broadly Reactive Antibodies in Humans.

    Science.gov (United States)

    Stadlbauer, Daniel; Rajabhathor, Arvind; Amanat, Fatima; Kaplan, Daniel; Masud, Abusaleh; Treanor, John J; Izikson, Ruvim; Cox, Manon M; Nachbagauer, Raffael; Krammer, Florian

    2017-01-01

    Human influenza virus infections with avian subtype H7N9 viruses are a major public health concern and have encouraged the development of effective H7 prepandemic vaccines. In this study, baseline and postvaccination serum samples of individuals aged 18 years and older who received a recombinant H7 hemagglutinin vaccine with and without an oil-in-water emulsion (SE) adjuvant were analyzed using a panel of serological assays. While only a small proportion of individuals seroconverted to H7N9 as measured by the conventional hemagglutination inhibition assay, our data show strong induction of anti-H7 hemagglutinin antibodies as measured by an enzyme-linked immunosorbent assay (ELISA). In addition, cross-reactive antibodies against phylogenetically distant group 2 hemagglutinins were induced, presumably targeting the conserved stalk domain of the hemagglutinin. Further analysis confirmed an induction of stalk-specific antibodies, suggesting that epitopes outside the classical antigenic sites are targeted by this vaccine in the context of preexisting immunity to related H3 hemagglutinin. Antibodies induced by H7 vaccination also showed functional activity in antibody-dependent cell-mediated cytotoxicity reporter assays and microneutralization assays. Additionally, our data show that sera from hemagglutination inhibition seroconverters conferred protection in a passive serum transfer experiment against lethal H7N9 virus challenge in mice. Interestingly, sera from hemagglutination inhibition nonseroconverters also conferred partial protection in the lethal animal challenge model. In conclusion, while recombinant H7 vaccination fails to induce measurable levels of hemagglutination-inhibiting antibodies in most subjects, this vaccination regime induces homosubtypic and heterosubtypic cross-reactive binding antibodies that are functional and partly protective in a murine passive transfer challenge model. IMPORTANCE Zoonotic infections with high case fatality rates caused by

  3. The Peptide Vaccine Combined with Prior Immunization of a Conventional Diphtheria-Tetanus Toxoid Vaccine Induced Amyloid β Binding Antibodies on Cynomolgus Monkeys and Guinea Pigs

    Directory of Open Access Journals (Sweden)

    Akira Yano

    2015-01-01

    Full Text Available The reduction of brain amyloid beta (Aβ peptides by anti-Aβ antibodies is one of the possible therapies for Alzheimer’s disease. We previously reported that the Aβ peptide vaccine including the T-cell epitope of diphtheria-tetanus combined toxoid (DT induced anti-Aβ antibodies, and the prior immunization with conventional DT vaccine enhanced the immunogenicity of the peptide. Cynomolgus monkeys were given the peptide vaccine subcutaneously in combination with the prior DT vaccination. Vaccination with a similar regimen was also performed on guinea pigs. The peptide vaccine induced anti-Aβ antibodies in cynomolgus monkeys and guinea pigs without chemical adjuvants, and excessive immune responses were not observed. Those antibodies could preferentially recognize Aβ40, and Aβ42 compared to Aβ fibrils. The levels of serum anti-Aβ antibodies and plasma Aβ peptides increased in both animals and decreased the brain Aβ40 level of guinea pigs. The peptide vaccine could induce a similar binding profile of anti-Aβ antibodies in cynomolgus monkeys and guinea pigs. The peptide vaccination could be expected to reduce the brain Aβ peptides and their toxic effects via clearance of Aβ peptides by generated antibodies.

  4. Suppression of Aggrus/podoplanin-induced platelet aggregation and pulmonary metastasis by a single-chain antibody variable region fragment

    International Nuclear Information System (INIS)

    Miyata, Kenichi; Takagi, Satoshi; Sato, Shigeo; Morioka, Hiroshi; Shiba, Kiyotaka; Minamisawa, Tamiko; Takami, Miho; Fujita, Naoya

    2014-01-01

    Almost all highly metastatic tumor cells possess high platelet aggregating abilities, thereby form large tumor cell-platelet aggregates in the microvasculature. Embolization of tumor cells in the microvasculature is considered to be the first step in metastasis to distant organs. We previously identified the platelet aggregation-inducing factor expressed on the surfaces of highly metastatic tumor cells and named as Aggrus. Aggrus was observed to be identical to the marker protein podoplanin (alternative names, T1α, OTS-8, and others). Aggrus is frequently overexpressed in several types of tumors and enhances platelet aggregation by interacting with the platelet receptor C-type lectin-like receptor 2 (CLEC-2). Here, we generated a novel single-chain antibody variable region fragment (scFv) by linking the variable regions of heavy and light chains of the neutralizing anti-human Aggrus monoclonal antibody MS-1 with a flexible peptide linker. Unfortunately, the generated KM10 scFv failed to suppress Aggrus-induced platelet aggregation in vitro. Therefore, we performed phage display screening and finally obtained a high-affinity scFv, K-11. K-11 scFv was able to suppress Aggrus-induced platelet aggregation in vitro. Moreover, K-11 scFv prevented the formation of pulmonary metastasis in vivo. These results suggest that K-11 scFv may be useful as metastasis inhibitory scFv and is expected to aid in the development of preclinical and clinical examinations of Aggrus-targeted cancer therapies

  5. Broader HIV-1 neutralizing antibody responses induced by envelope glycoprotein mutants based on the EIAV attenuated vaccine

    Directory of Open Access Journals (Sweden)

    Liu Lianxing

    2010-09-01

    Full Text Available Abstract Background In order to induce a potent and cross-reactive neutralizing antibody (nAb, an effective envelope immunogen is crucial for many viral vaccines, including the vaccine for the human immunodeficiency virus (HIV. The Chinese equine infectious anemia virus (EIAV attenuated vaccine has controlled the epidemic of this virus after its vaccination in over 70 million equine animals during the last 3 decades in China. Data from our past studies demonstrate that the Env protein of this vaccine plays a pivotal role in protecting horses from both homologous and heterogeneous EIAV challenges. Therefore, the amino acid sequence information from the Chinese EIAV attenuated vaccine, in comparison with the parental wild-type EIAV strains, was applied to modify the corresponding region of the envelope glycoprotein of HIV-1 CN54. The direction of the mutations was made towards the amino acids conserved in the two EIAV vaccine strains, distinguishing them from the two wild-type strains. The purpose of the modification was to enhance the immunogenicity of the HIV Env. Results The induced nAb by the modified HIV Env neutralized HIV-1 B and B'/C viruses at the highest titer of 1:270. Further studies showed that a single amino acid change in the C1 region accounts for the substantial enhancement in induction of anti-HIV-1 neutralizing antibodies. Conclusions This study shows that an HIV envelope modified by the information of another lentivirus vaccine induces effective broadly neutralizing antibodies. A single amino acid mutation was found to increase the immunogenicity of the HIV Env.

  6. HIV antibodies for treatment of HIV infection.

    Science.gov (United States)

    Margolis, David M; Koup, Richard A; Ferrari, Guido

    2017-01-01

    The bar is high to improve on current combination antiretroviral therapy (ART), now highly effective, safe, and simple. However, antibodies that bind the HIV envelope are able to uniquely target the virus as it seeks to enter new target cells, or as it is expressed from previously infected cells. Furthermore, the use of antibodies against HIV as a therapeutic may offer advantages. Antibodies can have long half-lives, and are being considered as partners for long-acting antiretrovirals for use in therapy or prevention of HIV infection. Early studies in animal models and in clinical trials suggest that such antibodies can have antiviral activity but, as with small-molecule antiretrovirals, the issues of viral escape and resistance will have to be addressed. Most promising, however, are the unique properties of anti-HIV antibodies: the potential ability to opsonize viral particles, to direct antibody-dependent cellular cytotoxicity (ADCC) against actively infected cells, and ultimately the ability to direct the clearance of HIV-infected cells by effector cells of the immune system. These distinctive activities suggest that HIV antibodies and their derivatives may play an important role in the next frontier of HIV therapeutics, the effort to develop treatments that could lead to an HIV cure. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  7. HIV antibodies for treatment of HIV infection

    Science.gov (United States)

    Margolis, David M.; Koup, Richard A.; Ferrari, Guido

    2016-01-01

    Summary The bar is high to improve on current combination antiretroviral therapy (ART), now highly effective, safe, and simple. However antibodies that bind the HIV envelope are able to uniquely target the virus as it seeks to enter new target cells, or as it is expressed from previously infected cells. Further, the use of antibodies against HIV as a therapeutic may offer advantages. Antibodies can have long half-lives, and are being considered as partners for long-acting antiretrovirals for use in therapy or prevention of HIV infection. Early studies in animal models and in clinical trials suggest that such antibodies can have antiviral activity but, as with small molecule antiretrovirals, the issues of viral escape and resistance will have to be addressed. Most promising, however, are the unique properties of anti-HIV antibodies: the potential ability to opsonize viral particles, to direct antibody-dependent cellular cytotoxicity (ADCC) against actively infected cells, and ultimately the ability to direct the clearance of HIV-infected cells by effector cells of the immune system. These distinctive activities suggest that HIV antibodies and their derivatives may play an important role in the next frontier of HIV therapeutics, the effort to develop treatments that could lead to an HIV cure. PMID:28133794

  8. Antibody constant region peptides can display immunomodulatory activity through activation of the Dectin-1 signalling pathway.

    Directory of Open Access Journals (Sweden)

    Elena Gabrielli

    Full Text Available We previously reported that a synthetic peptide with sequence identical to a CDR of a mouse monoclonal antibody specific for difucosyl human blood group A exerted an immunomodulatory activity on murine macrophages. It was therapeutic against systemic candidiasis without possessing direct candidacidal properties. Here we demonstrate that a selected peptide, N10K, putatively deriving from the enzymatic cleavage of the constant region (Fc of human IgG(1, is able to induce IL-6 secretion and pIkB-α activation. More importantly, it causes an up-regulation of Dectin-1 expression. This leads to an increased activation of β-glucan-induced pSyk, CARD9 and pIkB-α, and an increase in the production of pro-inflammatory cytokines such as IL-6, IL-12, IL-1β and TNF-α. The increased activation of this pathway coincides with an augmented phagocytosis of non opsonized Candida albicans cells by monocytes. The findings suggest that some Fc-peptides, potentially deriving from the proteolysis of immunoglobulins, may cause an unexpected immunoregulation in a way reminiscent of innate immunity molecules.

  9. CD3 directed bispecific antibodies induce increased lymphocyte-endothelial cell interactions in vitro

    NARCIS (Netherlands)

    Molema, G; Tervaert, JWC; Kroesen, BJ; Helfrich, W; Meijer, DKF; de Leij, LFMH

    Bispecific antibody (BsMAb) BIS-1 has been developed to redirect the cytolytic activity of cytotoxic T lymphocytes (CTL) to epithelial glycoprotein-2 (EGP-2) expressing tumour cells; intravenous administration of BIS-1 F(ab')(2) to carcinoma patients in a phase I/II clinical trial, caused

  10. How does the recombinant human interferon beta induce antibodies in immune tolerant mice?

    NARCIS (Netherlands)

    Kijanka, G.M.

    2013-01-01

    Therapeutic proteins revolutionized the treatment of severe diseases like multiple sclerosis, diabetes, haemophilia and many more. Unfortunately, their usage is often limited due to the formation of anti drug antibodies (ADAs), which may block the activity of these protein drugs and may lead to

  11. Single chain variable fragment antibodies block aggregation and toxicity induced by familial ALS-linked mutant forms of SOD1.

    Science.gov (United States)

    Ghadge, Ghanashyam D; Pavlovic, John D; Koduvayur, Sujatha P; Kay, Brian K; Roos, Raymond P

    2013-08-01

    Approximately 10% of amyotrophic lateral sclerosis (ALS) cases are familial (known as FALS) with an autosomal dominant inheritance pattern, and ~25% of FALS cases are caused by mutations in Cu/Zn superoxide dismutase (SOD1). There is convincing evidence that mutant SOD1 (mtSOD1) kills motor neurons (MNs) because of a gain-of-function toxicity, most likely related to aggregation of mtSOD1. A number of recent reports have suggested that antibodies can be used to treat mtSOD1-induced FALS. To follow up on the use of antibodies as potential therapeutics, we generated single chain fragments of variable region antibodies (scFvs) against SOD1, and then expressed them as 'intrabodies' within a motor neuron cell line. In the present study, we describe isolation of human scFvs that interfere with mtSOD1 in vitro aggregation and toxicity. These scFvs may have therapeutic potential in sporadic ALS, as well as FALS, given that sporadic ALS may also involve abnormalities in the SOD1 protein or activity. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. High-throughput pseudovirion-based neutralization assay for analysis of natural and vaccine-induced antibodies against human papillomaviruses.

    Directory of Open Access Journals (Sweden)

    Peter Sehr

    Full Text Available A highly sensitive, automated, purely add-on, high-throughput pseudovirion-based neutralization assay (HT-PBNA with excellent repeatability and run-to-run reproducibility was developed for human papillomavirus types (HPV 16, 18, 31, 45, 52, 58 and bovine papillomavirus type 1. Preparation of 384 well assay plates with serially diluted sera and the actual cell-based assay are separated in time, therefore batches of up to one hundred assay plates can be processed sequentially. A mean coefficient of variation (CV of 13% was obtained for anti-HPV 16 and HPV 18 titers for a standard serum tested in a total of 58 repeats on individual plates in seven independent runs. Natural antibody response was analyzed in 35 sera from patients with HPV 16 DNA positive cervical intraepithelial neoplasia grade 2+ lesions. The new HT-PBNA is based on Gaussia luciferase with increased sensitivity compared to the previously described manual PBNA (manPBNA based on secreted alkaline phosphatase as reporter. Titers obtained with HT-PBNA were generally higher than titers obtained with the manPBNA. A good linear correlation (R(2 = 0.7 was found between HT-PBNA titers and anti-HPV 16 L1 antibody-levels determined by a Luminex bead-based GST-capture assay for these 35 sera and a Kappa-value of 0.72, with only 3 discordant sera in the low titer range. In addition to natural low titer antibody responses the high sensitivity of the HT-PBNA also allows detection of cross-neutralizing antibodies induced by commercial HPV L1-vaccines and experimental L2-vaccines. When analyzing the WHO international standards for HPV 16 and 18 we determined an analytical sensitivity of 0.864 and 1.105 mIU, respectively.

  13. Intratypic heterologous vaccination of calves can induce an antibody response in presence of maternal antibodies against foot-and-mouth disease virus

    NARCIS (Netherlands)

    Dekker, A.; Eble, P.L.; Stockhofe-Zurwieden, N.; Chenard, G.

    2014-01-01

    Background - Maternal antibodies can interfere with foot-and-mouth disease vaccination. In this study we determined whether intratypic heterologous vaccination could help to improve herd immunity. Results - In unvaccinated calves, a half-life of maternal antibodies of 21 days was determined. At two

  14. Single mutation induced H3N2 hemagglutinin antibody neutralization: a free energy perturbation study.

    Science.gov (United States)

    Zhou, Ruhong; Das, Payel; Royyuru, Ajay K

    2008-12-11

    The single mutation effect on the binding affinity of H3N2 viral protein hemagglutinin (HA) with the monoclonical antibody fragment (Fab) is studied in this paper using the free energy perturbation (FEP) simulations. An all-atom protein model with explicit solvents is used to perform an aggregate of several microsecond FEP molecular dynamics simulations. A recent experiment shows that a single mutation in H3N2 HA, T131I, increases the antibody-antigen dissociation constant Kd by a factor of approximately 4000 (equivalent to a binding affinity decrease of approximately 5 kcal/mol), thus introducing an escape of the antibody (Ab) neutralization. Our FEP result confirms this experimental finding by estimating the HA-Ab binding affinity decrease of 5.2 +/- 0.9 kcal/mol but with a somewhat different molecular mechanism from the experimental findings. Detailed analysis reveals that this large binding affinity decrease in the T131I mutant is mainly due to the displacement of two bridge water molecules otherwise present in the wild-type HA/Ab interface. The decomposition of the binding free energy supports this observation, as the major contribution to the binding affinity is from the electrostatic interactions. In addition, we find that the loss of the binding affinity is also related to the large conformational distortion of one loop (loop 155-161) in the unbound state of the mutant. We then simulate all other possible mutations for this specific mutation site T131, and predict a few more mutations with even larger decreases in the binding affinity (i.e., better candidates for antibody neutralization), such as T131W, T131Y, and T131F. As for further validation, we have also modeled another mutation, S157L, with experimental binding affinity available (Kd increasing approximately 500 times), and found a binding affinity decrease of 4.1 +/- 1.0 kcal/mol, which is again in excellent agreement with experiment. These large scale simulations might provide new insights into the

  15. Protective antibody and CD8+ T-cell responses to the Plasmodium falciparum circumsporozoite protein induced by a nanoparticle vaccine.

    Directory of Open Access Journals (Sweden)

    Stephen A Kaba

    Full Text Available The worldwide burden of malaria remains a major public health problem due, in part, to the lack of an effective vaccine against the Plasmodium falciparum parasite. An effective vaccine will most likely require the induction of antigen specific CD8(+ and CD4(+ T-cells as well as long-lasting antibody responses all working in concert to eliminate the infection. We report here the effective modification of a self-assembling protein nanoparticle (SAPN vaccine previously proven effective in control of a P. berghei infection in a rodent model to now present B- and T-cell epitopes of the human malaria parasite P. falciparum in a platform capable of being used in human subjects.To establish the basis for a SAPN-based vaccine, B- and CD8(+ T-cell epitopes from the P. falciparum circumsporozoite protein (PfCSP and the universal CD4 T-helper epitope PADRE were engineered into a versatile small protein (∼125 amino acids that self-assembles into a spherical nanoparticle repetitively displaying the selected epitopes. P. falciparum epitope specific immune responses were evaluated in mice using a transgenic P. berghei malaria parasite of mice expressing the human malaria full-length P. falciparum circumsporozoite protein (Tg-Pb/PfCSP. We show that SAPN constructs, delivered in saline, can induce high-titer, long-lasting (1 year protective antibody and poly-functional (IFNγ(+, IL-2(+ long-lived central memory CD8(+ T-cells. Furthermore, we demonstrated that these Ab or CD8(+ T-cells can independently provide sterile protection against a lethal challenge of the transgenic parasites.The SAPN construct induces long-lasting antibody and cellular immune responses to epitope specific sequences of the P. falciparum circumsporozoite protein (PfCSP and prevents infection in mice by a transgenic P. berghei parasite displaying the full length PfCSP.

  16. Adenovirus Particles that Display the Plasmodium falciparum Circumsporozoite Protein NANP Repeat Induce Sporozoite-Neutralizing Antibodies in Mice

    Science.gov (United States)

    Palma, Christopher; Overstreet, Michael G.; Guedon, Jean-Marc; Hoiczyk, Egbert; Ward, Cameron; Karen, Kasey A.; Zavala, Fidel; Ketner, Gary

    2011-01-01

    Adenovirus particles can be engineered to display exogenous peptides on their surfaces by modification of viral capsid proteins, and particles that display pathogen-derived peptides can induce protective immunity. We constructed viable recombinant adenoviruses that display B-cell epitopes from the Plasmodium falciparum circumsporozoite protein (PfCSP) in the major adenovirus capsid protein, hexon. Recombinants induced high-titer antibodies against CSP when injected intraperitoneally into mice. Serum obtained from immunized mice recognized both recombinant PfCSP protein and P. falciparum sporozoites, and neutralized P. falciparum sporozoites in vitro. Replicating adenovirus vaccines have provided economical protection against adenovirus disease for over three decades. The recombinants described here may provide a path to an affordable malaria vaccine in the developing world. PMID:21199707

  17. Proteomic profiling of antibody-inducing immunogens in tumor tissue identifies PSMA1, LAP3, ANXA3, and maspin as colon cancer markers

    Science.gov (United States)

    Yang, Qian; Roehrl, Michael H.; Wang, Julia Y.

    2018-01-01

    We hypothesized that cancer tissue immunogens – antigens capable of inducing specific antibody production in patients – are promising targets for development of precision diagnostics and humoral immunotherapies. We developed an innovative immuno-proteomic strategy and identified new immunogenic markers of colon cancer. Proteins from cancers and matched normal tissues were separated by 2D gel electrophoresis and blotted with serum antibodies from the same patients. Antibody-reactive proteins were sequenced by mass spectrometry and validated by Western blotting and immunohistochemistry. 170 serum antibody-reactive proteins were identified only in cancerous but not matched normal. Among these, proteasome subunit alpha type 1 (PSA1), leucine aminopeptidase 3 (LAP3), annexin A3 (ANXA3), and maspin (serpin B5) were reproducibly found in tissues from three patients. Differential expression patterns were confirmed in samples from eight patients with various stages of colon adenocarcinoma and liver metastases. These tumor-resident proteins and/or their associated serum antibodies may be promising markers for colon cancer screening and early diagnosis. Furthermore, tumor tissue-specific antibodies could potentially be exploited as immunotherapeutic targets against cancer. More generally, proteomic profiling of antibody-inducing cancer-associated immunogens represents a powerful generic method for uncovering the tumor antigen-ome, i.e., the totality of immunogenic tumor-associated proteins. PMID:29423100

  18. An alphavirus vector overcomes the presence of neutralizing antibodies and elevated numbers of Tregs to induce immune responses in humans with advanced cancer.

    Science.gov (United States)

    Morse, Michael A; Hobeika, Amy C; Osada, Takuya; Berglund, Peter; Hubby, Bolyn; Negri, Sarah; Niedzwiecki, Donna; Devi, Gayathri R; Burnett, Bruce K; Clay, Timothy M; Smith, Jonathan; Lyerly, H Kim

    2010-09-01

    Therapeutic anticancer vaccines are designed to boost patients' immune responses to tumors. One approach is to use a viral vector to deliver antigen to in situ DCs, which then activate tumor-specific T cell and antibody responses. However, vector-specific neutralizing antibodies and suppressive cell populations such as Tregs remain great challenges to the efficacy of this approach. We report here that an alphavirus vector, packaged in virus-like replicon particles (VRP) and capable of efficiently infecting DCs, could be repeatedly administered to patients with metastatic cancer expressing the tumor antigen carcinoembryonic antigen (CEA) and that it overcame high titers of neutralizing antibodies and elevated Treg levels to induce clinically relevant CEA-specific T cell and antibody responses. The CEA-specific antibodies mediated antibody-dependent cellular cytotoxicity against tumor cells from human colorectal cancer metastases. In addition, patients with CEA-specific T cell responses exhibited longer overall survival. These data suggest that VRP-based vectors can overcome the presence of neutralizing antibodies to break tolerance to self antigen and may be clinically useful for immunotherapy in the setting of tumor-induced immunosuppression.

  19. Immunization of rabbits with nematode Ascaris lumbricoides antigens induces antibodies cross-reactive to house dust mite Dermatophagoides farinae antigens.

    Science.gov (United States)

    Nakazawa, Takuya; Khan, Al Fazal; Yasueda, Hiroshi; Saito, Akemi; Fukutomi, Yuma; Takai, Toshiro; Zaman, Khalequz; Yunus, Md; Takeuchi, Haruko; Iwata, Tsutomu; Akiyama, Kazuo

    2013-01-01

    There are controversial reports on the relationship between helminthic infection and allergic diseases. Although IgE cross-reactivity between nematode Ascaris antigens and house dust-mite allergens in allergic patients have been reported, whether Ascaris or the mite is the primary sensitizer remains unknown. Here we found that immunization of naïve animals with Ascaris lumbricoides (Al) antigens induced production of antibodies cross-reactive to mite antigens from Dermatophagoides farinae (Df). Sera from Bangladeshi children showed IgE reactivity to Ascaris and mite extracts. IgG from rabbits immunized with Al extract exhibited reactivity to Df antigens. Treatment of the anti-Al antibody with Df antigen-coupled beads eliminated the reactivity to Df antigens. In immunoblot analysis, an approximately 100-kDa Df band was the most reactive to anti-Al IgG. The present study is the first step towards the establishment of animal models to study the relationship between Ascaris infection and mite-induced allergic diseases.

  20. Synthetic Three-Component HIV-1 V3 Glycopeptide Immunogens Induce Glycan-Dependent Antibody Responses.

    Science.gov (United States)

    Cai, Hui; Orwenyo, Jared; Giddens, John P; Yang, Qiang; Zhang, Roushu; LaBranche, Celia C; Montefiori, David C; Wang, Lai-Xi

    2017-12-21

    Eliciting broadly neutralizing antibody (bNAb) responses against HIV-1 is a major goal for a prophylactic HIV-1 vaccine. One approach is to design immunogens based on known broadly neutralizing epitopes. Here we report the design and synthesis of an HIV-1 glycopeptide immunogen derived from the V3 domain. We performed glycopeptide epitope mapping to determine the minimal glycopeptide sequence as the epitope of V3-glycan-specific bNAbs PGT128 and 10-1074. We further constructed a self-adjuvant three-component immunogen that consists of a 33-mer V3 glycopeptide epitope, a universal T helper epitope P30, and a lipopeptide (Pam 3 CSK 4 ) that serves as a ligand of Toll-like receptor 2. Rabbit immunization revealed that the synthetic self-adjuvant glycopeptide could elicit substantial glycan-dependent antibodies that exhibited broader recognition of HIV-1 gp120s than the non-glycosylated V3 peptide. These results suggest that the self-adjuvant synthetic glycopeptides can serve as an important component to elicit glycan-specific antibodies in HIV vaccine design. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Protective immunization with B16 melanoma induces antibody response and not cytotoxic T cell response

    International Nuclear Information System (INIS)

    Sarzotti, M.; Sriyuktasuth, P.; Klimpel, G.R.; Cerny, J.

    1986-01-01

    C57BL/6 mice immunized with three intraperitoneal injections of syngeneic, irradiated B16 melanoma cells, became resistant to B16 tumor challenge. Immunized mice had high levels of serum antibody against a membrane antigen of B16 cells. The B16 antigen recognized by the anti-B16 sera formed a major band of 90 KD in gel electrophoresis. The anti-B16 antibody was partially protective when mixed with B16 cells and injected into normal recipient mice. Surprisingly, B16 resistance mice were incapable of generating cytotoxic T cells (CTL) specific for the B16 tumor. Both spleen and lymph node cell populations from immunized mice did not generate B16-specific CTL. Allogeneic mice (DBA/2 or C3H) were also unable to generate B16-specific CTL: however, alloreactive CTL produced in these strains of mice by immunization with C57BL/6 lymphocytes, did kill B16 target cells. Interestingly, spleen cells from syngeneic mice immunized with B16 tumor produced 6-fold more interleukin-2 (IL-2) than normal spleen cells, in vitro. These data suggest that immunization with B16 tumor activates a helper subset of T cells (for antibody and IL-2 production) but not the effector CTL response

  2. The NTS-DBL2X region of VAR2CSA induces cross-reactive antibodies that inhibit adhesion of several Plasmodium falciparum isolates to chondroitin sulfate A.

    Science.gov (United States)

    Bigey, Pascal; Gnidehou, Sédami; Doritchamou, Justin; Quiviger, Mickael; Viwami, Firmine; Couturier, Aude; Salanti, Ali; Nielsen, Morten A; Scherman, Daniel; Deloron, Philippe; Tuikue Ndam, Nicaise

    2011-10-01

    Binding to chondroitin sulfate A by VAR2CSA, a parasite protein expressed on infected erythrocytes, allows placental sequestration of Plasmodium falciparum-infected erythrocytes. This leads to severe consequences such as maternal anemia, stillbirths, and intrauterine growth retardation. The latter has been clearly associated to increased morbidity and mortality of the infants. Acquired anti-VAR2CSA antibodies have been associated with improved pregnancy outcomes, suggesting a vaccine could prevent the syndrome. However, identifying functionally important regions in the large VAR2CSA protein is difficult. Using genetic immunization, we raised polyclonal antisera against overlapping segments of VAR2CSA in mice and rabbits. The adhesion-inhibition capacities of induced antisera and of specific antibodies purified from plasma of malaria-exposed pregnant women were assessed on laboratory-adapted parasite lines and field isolates expressing VAR2CSA. Competition enzyme-linked immunosorbent assay (ELISA) was employed to analyze functional resemblance between antibodies induced in animals and those naturally acquired by immune multigravidae. Antibodies targeting the N-terminal sequence (NTS) up to DBL2X (NTS-DBL2X) efficiently blocked parasite adhesion to chondroitin sulfate A in a manner similar to that of antibodies raised against the entire VAR2CSA extracellular domain. Interestingly, naturally acquired antibodies and those induced by vaccination against NTS-DBL2X target overlapping strain-transcendent anti-adhesion epitopes. This study highlights an important step achieved toward development of a protective vaccine against placental malaria.

  3. Fluorescence Adherence Inhibition Assay: A Novel Functional Assessment of Blocking Virus Attachment by Vaccine-Induced Antibodies.

    Directory of Open Access Journals (Sweden)

    Atul Asati

    Full Text Available Neutralizing antibodies induced by vaccination or natural infection play a critically important role in protection against the viral diseases. In general, neutralization of the viral infection occurs via two major pathways: pre- and post-attachment modes, the first being the most important for such infections as influenza and polio, the latter being significant for filoviruses. Neutralizing capacity of antibodies is typically evaluated by virus neutralization assays that assess reduction of viral infectivity to the target cells in the presence of functional antibodies. Plaque reduction neutralization test, microneutralization and immunofluorescent assays are often used as gold standard virus neutralization assays. However, these methods are associated with several important prerequisites such as use of live virus requiring safety precautions, tedious evaluation procedure and long assessment time. Hence, there is a need for a robust, inexpensive high throughput functional assay that can be performed rapidly using inactivated virus, without extensive safety precautions. Herein, we report a novel high throughput Fluorescence Adherence Inhibition assay (fADI using inactivated virus labeled with fluorescent secondary antibodies virus and Vero cells or erythrocytes as targets. It requires only few hours to assess pre-attachment neutralizing capacity of donor sera. fADI assay was tested successfully on donors immunized with polio, yellow fever and influenza vaccines. To further simplify and improve the throughput of the assay, we have developed a mathematical approach for calculating the 50% titers from a single sample dilution, without the need to analyze multi-point titration curves. Assessment of pre- and post-vaccination human sera from subjects immunized with IPOL®, YF-VAX® and 2013-2014 Fluzone® vaccines demonstrated high efficiency of the assay. The results correlated very well with microneutralization assay performed independently by the FDA

  4. Heat shock proteins 70 and 90 from Clonorchis sinensis induce Th1 response and stimulate antibody production.

    Science.gov (United States)

    Chung, Eun Joo; Jeong, Young-Il; Lee, Myoung-Ro; Kim, Yu Jung; Lee, Sang-Eun; Cho, Shin-Hyeong; Lee, Won-Ja; Park, Mi-Yeoun; Ju, Jung-Won

    2017-03-01

    Heat shock proteins (HSPs) are found in all prokaryotes and most compartments of eukaryotic cells. Members of the HSP family mediate immune responses to tissue damage or cellular stress. However, little is known about the immune response induced by the oriental liver fluke, Clonorchis sinensis, even though this organism is carcinogenic to humans. We address this issue in the present study in mouse bone marrow dendritic cells (mBMDCs), using recombinant HSP70 and 90 from C. sinensis (rCsHSP70 and rCsHSP90). rCsHSP70 and rCsHSP90 were produced in an E. coli system. Purified recombinant proteins were treated in BMDCs isolated from C57BL/6 mice. T cells were isolated from Balb/c mice and co-cultured with activated mBMDCs. Expression of surface molecules was measured by flow cytometry and cytokine secretion was quantified using ELISA. C57BL/6 mice were divided into four groups, including peptide alone, peptide/Freund's adjuvant, peptide/CsHSP70, peptide/CsHSP90, and were immunized intraperitoneally three times. Two weeks after final immunization, antibodies against peptide were measured using ELISA. Both proteins induced a dose-dependent upregulation in major histocompatibility complex and co-stimulatory molecule expression and increased secretion of pro-inflammatory cytokines including interleukin (IL)-1β, -6, and -12p70 and tumor necrosis factor-α in mBMDCs. Furthermore, when allogenic T cells were incubated with mBMDCs activated by rCsHSP70 and rCsHSP90, the helper T cell (Th)1 cytokine interferon-γ was up-regulated whereas the level of the Th2 cytokine IL-4 was unchanged. These results indicate that rCsHSPs predominantly induce a Th1 response. Over and above these results, we also demonstrated that the production of peptide-specific antibodies can be activated after immunization via in vitro peptide binding with rCsHSP70 or rCsHSP90. This study showed for the first time that the HSP or HSP/peptide complexes of C. sinensis could be considered as a more effective

  5. Antibody recognizing 4-sulfated chondroitin sulfate proteoglycans restores memory in tauopathy-induced neurodegeneration.

    Science.gov (United States)

    Yang, Sujeong; Hilton, Sam; Alves, João Nuno; Saksida, Lisa M; Bussey, Timothy; Matthews, Russell T; Kitagawa, Hiroshi; Spillantini, Maria Grazia; Kwok, Jessica C F; Fawcett, James W

    2017-11-01

    Chondroitin sulfate proteoglycans (CSPGs) are the main active component of perineuronal nets (PNNs). Digestion of the glycosaminoglycan chains of CSPGs with chondroitinase ABC or transgenic attenuation of PNNs leads to prolongation of object recognition memory and activation of various forms of plasticity in the adult central nervous system. The inhibitory properties of the CSPGs depend on the pattern of sulfation of their glycosaminoglycans, with chondroitin 4-sulfate (C4S) being the most inhibitory form. In this study, we tested a number of candidates for functional blocking of C4S, leading to selection of an antibody, Cat316, which specifically recognizes C4S and blocks its inhibitory effects on axon growth. It also partly blocks binding of semaphorin 3A to PNNs and attenuates PNN formation. We asked whether injection of Cat316 into the perirhinal cortex would have the same effects on memory as chondroitinase ABC treatment. We found that masking C4S with the Cat316 antibody extended long-term object recognition memory in normal wild-type mice to 24 hours, similarly to chondroitinase or transgenic PNN attenuation. We then tested Cat316 for restoration of memory in a neurodegeneration model. Mice expressing tau with the P301S mutation showed profound loss of object recognition memory at 4 months of age. Injection of Cat316 into the perirhinal cortex normalized object recognition at 3 hours in P301S mice. These data indicate that Cat316 binding to C4S in the extracellular matrix can restore plasticity and memory in the same way as chondroitinase ABC digestion. Our results suggest that antibodies to C4S could be a useful therapeutic to restore memory function in neurodegenerative disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Neutralization of venom-induced hemorrhage by equine antibodies raised by immunization with a plasmid encoding a novel P-II metalloproteinase from the lancehead pitviper Bothrops asper.

    Science.gov (United States)

    Arce-Estrada, Viviana; Azofeifa-Cordero, Gabriela; Estrada, Ricardo; Alape-Girón, Alberto; Flores-Díaz, Marietta

    2009-01-14

    In this work, the cDNA encoding a novel P-II type metalloproteinase from Bothrops asper venom glands was cloned, sequenced and used for DNA immunization of animals with accelerated DNA-coated tungsten microparticles and the helius Gene Gun system. Specific antibodies against B. asper venom antigens were induced in mice co-immunized with the plasmid encoding the P-II metalloproteinase together with an expression plasmid encoding the murine IL-2. Similarly, specific antibodies against B. asper venom antigens were also induced in a horse co-immunized with the plasmid encoding the P-II metalloproteinase, together with a plasmid encoding the equine IL-6. The equine antibodies induced by immunization with the P-II metalloproteinase encoding plasmid cross react with several proteins of B. asper, Crotalus durissus durissus, and Lachesis stenophrys venoms in western blot, demonstrating antigenic similarity between the cloned metalloproteinase and other metalloproteinases present in these venoms. Furthermore, the equine antibodies induced by immunization with the P-II metalloproteinase encoding plasmid completely neutralized the hemorrhagic activity of the whole B. asper venom and partially the hemorrhagic activity of C. durissus durissus venom. The neutralizing ability of the produced antibodies raises, for the first time, the possibility of developing therapeutic antivenoms in horses by DNA immunization using tungsten microparticles.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-12-18

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

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

    DEFF Research Database (Denmark)

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

    2011-01-01

    We detected cross-reactive neutralizing antibodies (NtAb) against hepatitis C virus (HCV) in chimpanzees vaccinated with HCV-1 (genotype 1a) recombinant E1/E2 envelope glycoproteins. Five vaccinated chimpanzees, protected following HCV-1 challenge, were initially studied using the heterologous H77...... (genotype 1a) HCVpp assay. All animals had developed NtAb after the second vaccination; 4 animals had reciprocal titers of =200 at the time of challenge. Using genotypes 1a-6a HCV pseudoparticles (HCVpp) and cell culture-derived HCV (HCVcc) assays, cross-reactive NtAb were detected against 1a, 4a, 5a, and 6...

  9. Antibody responses in pregnancy-induced transmammary transmission of Ancylostoma caninum hookworm larvae.

    Science.gov (United States)

    Arasu, P; Heller, A

    1999-09-20

    Third stage larvae of the Ancylostoma caninum hookworm nematode have the capacity to infect a dog, abort the normal maturation pathway to become blood-feeding intestinal worms, and instead distribute throughout the body in a developmentally arrested state that is relatively resilient to most chemotherapeutic agents. During pregnancy, a percentage of the arrested larvae reactivate and transmit via the mammary glands to infect the nursing puppies with resulting iron-deficiency anemia and potential mortality. To determine if the suppression of parasite-specific antibody responses during pregnancy facilitates the reactivation and transmammary transfer of hookworm larvae, a murine model of A. caninum infection was used to compare the infected versus uninfected animals that were either bred or not bred. Initial comparisons of genetically divergent BALB/c versus C57BL/6 mice showed that both the strains mounted strong Th2 biased IgG1 and IgE antibody responses to A. caninum infection. Using the BALB/c strain for the breeding analyses, it was confirmed that larval transfer to the mouse pups only occurred during the post-partum lactational period. In the dams, levels of total and antigen-specific IgG1 and total IgE were highly correlated with parasite burden. During most phases of pregnancy and lactation, infected dams had lower total IgG1, IgG2a and IgE levels as compared to unbred mice at comparable times post-infection; this downward modulation of antibody responses supports the established dogma of a generalized immunosuppression associated with pregnancy. However, at parturition and post-partum lactation, antigen-specific IgG1 levels measured at 1:5000 serum dilutions were comparable between bred and unbred mice, and antigen-specific IgG2a levels at 1:100 serum dilutions were also not significantly different except for a marginal reduction in the bred mice at the lactational timepoint. The comparable anti-A. caninum IgG1 levels between bred and unbred mice, and low

  10. A Live Vector Expressing HPV16 L1 Generates an Adjuvant-Induced Antibody Response In-vivo.

    Science.gov (United States)

    Shirbaghaee, Zeinab; Bolhassani, Azam; Mirshafiey, Abbas; Motevalli, Fatemeh; Zohrei, Negar

    2015-12-01

    The association between human papillomavirus (HPV) infections and cervical cancer has suggested the design of prophylactic and therapeutic vaccines against genital warts. The HPV capsid has made of two L1 and L2 coat proteins that have produced late in viral infections. Regarding to the recent studies, two commercial prophylactic vaccines have based on L1 viral like particles (VLPs) could strongly induce antibody responses, and protect human body from HPV infections. However, the use of these HPV vaccines has hindered due to their high cost and some limitations. Currently, among various vaccination strategies, live vector-based vaccines have attracted a great attention. Herein, a non-pathogenic strain of the protozoan organism known as Leishmania tarentolae has utilized to induce potent humoral immunity in mice model. At first, cloning of HPV16 L1 gene into Leishmania expression vector has performed and confirmed by PCR and digestion with restriction enzymes. The promastigotes of Leishmania tarentolae (L.tar) have transfected with linearized DNA construct by electroporation. Protein expression has analyzed by SDS-PAGE and western blotting. Then, the immunogenicity of leishmania expressing L1 protein (L.tar-L1) has assessed in mice model. Our data has indicated that subcutaneous immunization of mice with the recombinant L.tar-L1 has led to enhance the levels of IgG1 and lgG2a in comparison with control groups. Furthermore, there was no significant increase in antibody levels between two and three times of immunizations. The recombinant live vector was able to induce humoral immunity in mice without need of any adjuvant. However, further studies have required to increase its efficiency.

  11. Dissecting Antibodies Induced by a Chimeric Yellow Fever-Dengue, Live-Attenuated, Tetravalent Dengue Vaccine (CYD-TDV) in Naive and Dengue-Exposed Individuals.

    Science.gov (United States)

    Henein, Sandra; Swanstrom, Jesica; Byers, Anthony M; Moser, Janice M; Shaik, S Farzana; Bonaparte, Matthew; Jackson, Nicholas; Guy, Bruno; Baric, Ralph; de Silva, Aravinda M

    2017-02-01

    Sanofi Pasteur has developed a chimeric yellow fever-dengue, live-attenuated, tetravalent dengue vaccine (CYD-TDV) that is currently approved for use in several countries. In clinical trials, CYD-TDV was efficacious at reducing laboratory-confirmed cases of dengue disease. Efficacy varied by dengue virus (DENV) serotype and prevaccination dengue immune status. We compared the properties of antibodies in naive and DENV-exposed individuals who received CYD-TDV. We depleted specific populations of DENV-reactive antibodies from immune serum samples to estimate the contribution of serotype-cross-reactive and type-specific antibodies to neutralization. Subjects with no preexisting immunity to DENV developed neutralizing antibodies to all 4 serotypes of DENV. Further analysis demonstrated that DENV4 was mainly neutralized by type-specific antibodies whereas DENV1, DENV2, and DENV3 were mainly neutralized by serotype cross-reactive antibodies. When subjects with preexisting immunity to DENV were vaccinated, they developed higher levels of neutralizing antibodies than naive subjects who were vaccinated. In preimmune subjects, CYD-TDV boosted cross-reactive neutralizing antibodies while maintaining type-specific neutralizing antibodies acquired before vaccination. Our results demonstrate that the quality of neutralizing antibodies induced by CYD-TDV varies depending on DENV serotype and previous immune status. We discuss the implications of these results for understanding vaccine efficacy. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  12. Novel transdermal photodynamic therapy using ATX-S10.Na(II) induces apoptosis of synovial fibroblasts and ameliorates collagen antibody-induced arthritis in mice.

    Science.gov (United States)

    Miyazawa, S; Nishida, K; Komiyama, T; Nakae, Y; Takeda, K; Yorimitsu, M; Kitamura, A; Kunisada, T; Ohtsuka, A; Inoue, H

    2006-06-01

    We aimed to test the effect of transdermal photodynamic therapy (PDT) on synovial proliferation in vitro and in vivo, using a novel photosensitizer, ATX-S10.Na(II). Synovial fibroblasts were obtained from patients with RA (RASF). Cell viability with or without PDT was determined by MTT assay. Cell morphology was examined by light and transmission electron microscopy. DNA fragmentation was labeled by TUNEL stain. Collagen antibody-induced arthritis (CAIA) was induced in DBA/1 mice, and the effects of transdermal PDT were evaluated by clinical and histological examination. PDT showed drug concentration-dependent and laser dose-dependent cytotoxicity on RASF. TUNEL stain and TEM study revealed the induction of apoptotic cell death of RASF. Transdermal PDT significantly reduced clinical arthritis and synovial inflammation in this model of arthritis. These results suggest that transdermal PDT using ATX-S10.Na(II) might be a novel less invasive treatment strategy for small joint arthritis and tenosynovitis.

  13. A tetravalent virus-like particle vaccine designed to display domain III of dengue envelope proteins induces multi-serotype neutralizing antibodies in mice and macaques which confer protection against antibody dependent enhancement in AG129 mice.

    Directory of Open Access Journals (Sweden)

    Viswanathan Ramasamy

    2018-01-01

    Full Text Available Dengue is one of the fastest spreading vector-borne diseases, caused by four antigenically distinct dengue viruses (DENVs. Antibodies against DENVs are responsible for both protection as well as pathogenesis. A vaccine that is safe for and efficacious in all people irrespective of their age and domicile is still an unmet need. It is becoming increasingly apparent that vaccine design must eliminate epitopes implicated in the induction of infection-enhancing antibodies.We report a Pichia pastoris-expressed dengue immunogen, DSV4, based on DENV envelope protein domain III (EDIII, which contains well-characterized serotype-specific and cross-reactive epitopes. In natural infection, <10% of the total neutralizing antibody response is EDIII-directed. Yet, this is a functionally relevant domain which interacts with the host cell surface receptor. DSV4 was designed by in-frame fusion of EDIII of all four DENV serotypes and hepatitis B surface (S antigen and co-expressed with unfused S antigen to form mosaic virus-like particles (VLPs. These VLPs displayed EDIIIs of all four DENV serotypes based on probing with a battery of serotype-specific anti-EDIII monoclonal antibodies. The DSV4 VLPs were highly immunogenic, inducing potent and durable neutralizing antibodies against all four DENV serotypes encompassing multiple genotypes, in mice and macaques. DSV4-induced murine antibodies suppressed viremia in AG129 mice and conferred protection against lethal DENV-4 virus challenge. Further, neither murine nor macaque anti-DSV4 antibodies promoted mortality or inflammatory cytokine production when passively transferred and tested in an in vivo dengue disease enhancement model of AG129 mice.Directing the immune response to a non-immunodominant but functionally relevant serotype-specific dengue epitope of the four DENV serotypes, displayed on a VLP platform, can help minimize the risk of inducing disease-enhancing antibodies while eliciting effective tetravalent

  14. Treatment with anti-NAP monoclonal antibody reduces disease severity in murine model of novel angiogenic protein-induced or ovalbumin-induced arthritis.

    Science.gov (United States)

    Nataraj, N B; Krishnamurthy, J; Salimath, B P

    2013-02-01

    Rheumatoid arthritis (RA) is a polyarticular inflammatory, angiogenic disease. Synovial angiogenesis contributes to inflammation in RA. In this study we have developed an arthritic model in rats using a novel angiogenic protein (NAP), isolated from human synovial fluid of RA patients. We produced anti-NAP monoclonal antibodies (mAbs) and investigated the therapeutic efficacy of the same in adjuvant-induced or NAP-induced arthritis as a model of human RA. The treatment of arthritic rats with anti-NAP mAbs resulted in effective amelioration of paw oedema, radiological arthritic characteristics, serum levels of vascular endothelial growth factor (VEGF) and NAP, compared to that of untreated arthritic animals. Further, profiling of angiogenic markers such as synovial microvessel density, angiogenesis, CD31, VEGF and fms-like tyrosine kinase (Flt1) by immunohistochemistry both in arthritic and anti-NAP mAb-treated animals revealed the efficacy of mAb as an anti-angiogenic functional antibody. Therefore, NAP may be an attractive target to design anti-angiogenic and anti-arthritic therapies to control the pathogenesis of arthritis. © 2012 British Society for Immunology.

  15. A multi-subunit Chlamydia vaccine inducing neutralizing antibodies and strong IFN-γ(+) CMI responses protects against a genital infection in minipigs

    DEFF Research Database (Denmark)

    Bøje, Sarah; Olsen, Anja Weinreich; Erneholm, Karin

    2016-01-01

    Chlamydia is the most widespread sexually transmitted bacterial disease and a prophylactic vaccine is highly needed. Ideally, this vaccine is required to induce a combined response of Th1 cell-mediated immune (CMI) response in concert with neutralizing antibodies. Using a novel Göttingen minipig...... animal model, we evaluated the immunogenicity and efficacy of a multi-subunit vaccine formulated in the strong Th1-inducing adjuvant CAF01. We evaluated a mixture of two fusion proteins (Hirep1 and CTH93) designed to promote either neutralizing antibodies or cell-mediated immunity, respectively. Hirep1...

  16. Isolation of highly active monoclonal antibodies against multiresistant gram-positive bacteria.

    Directory of Open Access Journals (Sweden)

    Friederike S Rossmann

    Full Text Available Multiresistant nosocomial pathogens often cause life-threatening infections that are sometimes untreatable with currently available antibiotics. Staphylococci and enterococci are the predominant Gram-positive species associated with hospital-acquired infections. These infections often lead to extended hospital stay and excess mortality. In this study, a panel of fully human monoclonal antibodies was isolated from a healthy individual by selection of B-cells producing antibodies with high opsonic killing against E. faecalis 12030. Variable domains (VH and VL of these immunoglobulin genes were amplified by PCR and cloned into an eukaryotic expression vector containing the constant domains of a human IgG1 molecule and the human lambda constant domain. These constructs were transfected into CHO cells and culture supernatants were collected and tested by opsonophagocytic assay against E. faecalis and S. aureus strains (including MRSA. At concentrations of 600 pg/ml, opsonic killing was between 40% and 70% against all strains tested. Monoclonal antibodies were also evaluated in a mouse sepsis model (using S. aureus LAC and E. faecium, a mouse peritonitis model (using S. aureus Newman and LAC and a rat endocarditis model (using E. faecalis 12030 and were shown to provide protection in all models at a concentration of 4 μg/kg per animal. Here we present a method to produce fully human IgG1 monoclonal antibodies that are opsonic in vitro and protective in vivo against several multiresistant Gram-positive bacteria. The monoclonal antibodies presented in this study are significantly more effective compared to another monoclonal antibody currently in clinical trials.

  17. Antibody functionalized graphene biosensor for label-free electrochemical immunosensing of fibrinogen, an indicator of trauma induced coagulopathy.

    Science.gov (United States)

    Saleem, Waqas; Salinas, Carlos; Watkins, Brian; Garvey, Gavin; Sharma, Anjal C; Ghosh, Ritwik

    2016-12-15

    An antibody, specific to fibrinogen, has been covalently attached to graphene and deposited onto screen printed electrodes using a chitosan hydrogel binder to prepare an inexpensive electrochemical fibrinogen biosensor. Fourier Transform Infrared (FT-IR) spectroscopy has been utilized to confirm the presence of the antibody on the graphene scaffold. Electrochemical Impedance Spectroscopy (EIS) has been utilized to demonstrate that the biosensor responds in a selective manner to fibrinogen in aqueous media even in the presence of plasminogen, a potentially interfering molecule in the coagulopathy cascade. Furthermore, the biosensor was shown to reliably sense fibrinogen in the presence of high background serum albumin levels. Finally, we demonstrated detection of clinically relevant fibrinogen concentrations (938-44,542μg/dL) from human serum and human whole blood samples using this biosensor. This biosensor can potentially be used in a point-of-care device to detect the onset of coagulopathy and monitor response following therapeutic intervention in trauma patients. Thus this biosensor may improve the clinical management of patients with trauma-induced coagulopathy. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Chemical changes demonstrated in cartilage by synchrotron infrared microspectroscopy in an antibody-induced murine model of rheumatoid arthritis

    Science.gov (United States)

    Croxford, Allyson M.; Selva Nandakumar, Kutty; Holmdahl, Rikard; Tobin, Mark J.; McNaughton, Don; Rowley, Merrill J.

    2011-06-01

    Collagen antibody-induced arthritis develops in mice following passive transfer of monoclonal antibodies (mAbs) to type II collagen (CII) and is attributed to effects of proinflammatory immune complexes, but transferred mAbs may react directly and damagingly with CII. To determine whether such mAbs cause cartilage damage in vivo in the absence of inflammation, mice lacking complement factor 5 that do not develop joint inflammation were injected intravenously with two arthritogenic mAbs to CII, M2139 and CIIC1. Paws were collected at day 3, decalcified, paraffin embedded, and 5-μm sections were examined using standard histology and synchrotron Fourier-transform infrared microspectroscopy (FTIRM). None of the mice injected with mAb showed visual or histological evidence of inflammation but there were histological changes in the articular cartilage including loss of proteoglycan and altered chondrocyte morphology. Findings using FTIRM at high lateral resolution revealed loss of collagen and the appearance of a new peak at 1635 cm-1 at the surface of the cartilage interpreted as cellular activation. Thus, we demonstrate the utility of synchrotron FTIRM for examining chemical changes in diseased cartilage at the microscopic level and establish that arthritogenic mAbs to CII do cause cartilage damage in vivo in the absence of inflammation.

  19. MuSK induced experimental autoimmune myasthenia gravis does not require IgG1 antibody to MuSK.

    Science.gov (United States)

    Küçükerden, Melike; Huda, Ruksana; Tüzün, Erdem; Yılmaz, Abdullah; Skriapa, Lamprini; Trakas, Nikos; Strait, Richard T; Finkelman, Fred D; Kabadayı, Sevil; Zisimopoulou, Paraskevi; Tzartos, Socrates; Christadoss, Premkumar

    2016-06-15

    Sera of myasthenia gravis (MG) patients with muscle-specific receptor kinase-antibody (MuSK-Ab) predominantly display the non-complement fixing IgG4 isotype. Similarly, mouse IgG1, which is the analog of human IgG4, is the predominant isotype in mice with experimental autoimmune myasthenia gravis (EAMG) induced by MuSK immunization. The present study was performed to determine whether IgG1 anti-MuSK antibody is required for immunized mice to develop EAMG. Results demonstrated a significant correlation between clinical severity of EAMG and levels of MuSK-binding IgG1+, IgG2+ and IgG3+ peripheral blood B cells in MuSK-immunized wild-type (WT) mice. Moreover, MuSK-immunized IgG1 knockout (KO) and WT mice showed similar EAMG severity, serum MuSK-Ab levels, muscle acetylcholine receptor concentrations, neuromuscular junction immunoglobulin and complement deposit ratios. IgG1 and IgG3 were the predominant anti-MuSK isotypes in WT and IgG1 KO mice, respectively. These observations demonstrate that non-IgG1 isotypes can mediate MuSK-EAMG pathogenesis. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Stringently Defined Otitis Prone Children Demonstrate Deficient Naturally Induced Mucosal Antibody Response to Moraxella catarrhalis Proteins

    Directory of Open Access Journals (Sweden)

    Dabin Ren

    2017-08-01

    Full Text Available Moraxella catarrhalis (Mcat is a prominent mucosal pathogen causing acute otitis media (AOM. We studied Mcat nasopharyngeal (NP colonization, AOM frequency and mucosal antibody responses to four vaccine candidate Mcat proteins: outer membrane protein (OMP CD, oligopeptide permease (Opp A, hemagglutinin (Hag, and Pilin A clade 2 (PilA2 from stringently defined otitis prone (sOP children, who experience the greatest burden of disease, compared to non-otitis prone (NOP children. sOP children had higher NP colonization of Mcat (30 vs. 22%, P = 0.0003 and Mcat-caused AOM rates (49 vs. 24%, P < 0.0001 than NOP children. Natural acquisition of mucosal antibodies to Mcat proteins OMP CD (IgG, P < 0.0001, OppA (IgG, P = 0.018, Hag (IgG and IgA, both P < 0.0001, and PilA2 (IgA, P < 0.0001 was lower in sOP than NOP children. Higher levels of mucosal IgG to Hag (P = 0.039 and PilA2 (P = 0.0076, and IgA to OMP CD (P = 0.010, OppA (P = 0.030, and PilA2 (P = 0.043 were associated with lower carriage of Mcat in NOP but not sOP children. Higher levels of mucosal IgG to OMP CD (P = 0.0070 and Hag (P = 0.0003, and IgA to Hag (P = 0.0067 at asymptomatic colonization than those at onset of AOM were associated with significantly lower rate of Mcat NP colonization progressing to AOM in NOP compared to sOP children (3 vs. 26%, P < 0.0001. In conclusion, sOP children had a diminished mucosal antibody response to Mcat proteins, which was associated with higher frequencies of asymptomatic NP colonization and NP colonization progressing to Mcat-caused AOM. Enhancing Mcat antigen-specific mucosal immune responses to levels higher than achieved by natural exposure will be necessary to prevent AOM in sOP children.

  1. Prostaglandin D2 Receptor DP1 Antibodies Predict Vaccine-induced and Spontaneous Narcolepsy Type 1: Large-scale Study of Antibody Profiling

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    Helle Sadam

    2018-03-01

    Full Text Available Background: Neuropathological findings support an autoimmune etiology as an underlying factor for loss of orexin-producing neurons in spontaneous narcolepsy type 1 (narcolepsy with cataplexy; sNT1 as well as in Pandemrix influenza vaccine-induced narcolepsy type 1 (Pdmx-NT1. The precise molecular target or antigens for the immune response have, however, remained elusive. Methods: Here we have performed a comprehensive antigenic repertoire analysis of sera using the next-generation phage display method - mimotope variation analysis (MVA. Samples from 64 children and adolescents were analyzed: 10 with Pdmx-NT1, 6 with sNT1, 16 Pandemrix-vaccinated, 16 H1N1 infected, and 16 unvaccinated healthy individuals. The diagnosis of NT1 was defined by the American Academy of Sleep Medicine international criteria of sleep disorders v3. Findings: Our data showed that although the immunoprofiles toward vaccination were generally similar in study groups, there were also striking differences in immunoprofiles between sNT1 and Pdmx-NT1 groups as compared with controls. Prominent immune response was observed to a peptide epitope derived from prostaglandin D2 receptor (DP1, as well as peptides homologous to B cell lymphoma 6 protein. Further validation confirmed that these can act as true antigenic targets in discriminating NT1 diseased along with a novel epitope of hemagglutinin of H1N1 to delineate exposure to H1N1. Interpretation: We propose that DP1 is a novel molecular target of autoimmune response and presents a potential diagnostic biomarker for NT1. DP1 is involved in the regulation of non-rapid eye movement (NREM sleep and thus alterations in its functions could contribute to the disturbed sleep regulation in NT1 that warrants further studies. Together our results also show that MVA is a helpful method for finding novel peptide antigens to classify human autoimmune diseases, possibly facilitating the design of better therapies. Keywords: Narcolepsy type 1

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

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    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.

  3. Gemcitabine-induced hemolytic uremic syndrome mimicking scleroderma renal crisis presenting with Raynaud's phenomenon, positive antinuclear antibodies and hypertensive emergency.

    Science.gov (United States)

    Yamada, Yuichiro; Suzuki, Keisuke; Nobata, Hironobu; Kawai, Hirohisa; Wakamatsu, Ryo; Miura, Naoto; Banno, Shogo; Imai, Hirokazu

    2014-01-01

    A 58-year-old woman who received gemcitabine for advanced gallbladder cancer developed an impaired renal function, thrombocytopenia, Raynaud's phenomenon, digital ischemic changes, a high antinuclear antibody titer and hypertensive emergency that mimicked a scleroderma renal crisis. A kidney biopsy specimen demonstrated onion-skin lesions in the arterioles and small arteries along with ischemic changes in the glomeruli, compatible with a diagnosis of hypertensive emergency (malignant hypertension). The intravenous administration of a calcium channel blocker, the oral administration of an angiotensin-converting enzyme inhibitor and angiotensin II receptor blocker and the transfusion of fresh frozen plasma were effective for treating the thrombocytopenia and progressive kidney dysfunction. Gemcitabine induces hemolytic uremic syndrome with accelerated hypertension and Raynaud's phenomenon, mimicking scleroderma renal crisis.

  4. Management of phenytoin-induced gingival enlargement in a patient with antiphospholipid antibody syndrome: A rare case report

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    Shilpa Sarvesh Urolagin

    2016-01-01

    Full Text Available Antiphospholipid antibody (APLA syndrome is a noninflammatory autoimmune disease, with innumerable clinical manifestations ranging from recurrent thrombosis and pregnancy morbidity to valvular lesions, transverse myelitis, thrombocytopenia, and hemolytic anemia. APLAs in antiphospholipid syndrome (APS are well-known risk factors for cerebrovascular accidents. Stroke is the most common manifestation of APS in the central nervous system. Gingival enlargement is a known side effect of phenytoin which is an antiepileptic drug. This can have a significant effect on the quality of life as well as increasing the oral bacterial load by generating plaque retention sites. The management of gingival overgrowth seems to be directed at controlling gingival inflammation through a good oral hygiene regimen. Thus, this case report aims to describe the conservative management of phenytoin-induced gingival enlargement combined with inflammatory enlargement in a patient with APLA syndrome.

  5. Maturation of Shark Single-Domain (IgNAR) Antibodies: Evidence for Induced-Fit Binding

    Energy Technology Data Exchange (ETDEWEB)

    Stanfield, R.L.; Dooley, H.; Verdino, P.; Flajnik, M.F.; Wilson, I.A.; /Scripps Res. Inst. /Maryland U.

    2007-07-13

    Sharks express an unusual heavy-chain isotype called IgNAR, whose variable regions bind antigen as independent soluble domains. To further probe affinity maturation of the IgNAR response, we structurally characterized the germline and somatically matured versions of a type II variable (V) region, both in the presence and absence of its antigen, hen egg-white lysozyme. Despite a disulfide bond linking complementarity determining regions (CDRs) 1 and 3, both germline and somatically matured V regions displayed significant structural changes in these CDRs upon complex formation with antigen. Somatic mutations in the IgNAR V region serve to increase the number of contacts with antigen, as reflected by a tenfold increase in affinity, and one of these mutations appears to stabilize the CDR3 region. In addition, a residue in the HV4 loop plays an important role in antibody-antigen interaction, consistent with the high rate of somatic mutations in this non-CDR loop.

  6. Vaccination with the Surface Proteins MUL_2232 and MUL_3720 of Mycobacterium ulcerans Induces Antibodies but Fails to Provide Protection against Buruli Ulcer.

    Science.gov (United States)

    Bolz, Miriam; Bénard, Angèle; Dreyer, Anita M; Kerber, Sarah; Vettiger, Andrea; Oehlmann, Wulf; Singh, Mahavir; Duthie, Malcolm S; Pluschke, Gerd

    2016-02-01

    Buruli ulcer, caused by infection with Mycobacterium ulcerans, is a chronic ulcerative neglected tropical disease of the skin and subcutaneous tissue that is most prevalent in West African countries. M. ulcerans produces a cytotoxic macrolide exotoxin called mycolactone, which causes extensive necrosis of infected subcutaneous tissue and the development of characteristic ulcerative lesions with undermined edges. While cellular immune responses are expected to play a key role against early intracellular stages of M. ulcerans in macrophages, antibody mediated protection might be of major relevance against advanced stages, where bacilli are predominantly found as extracellular clusters. To assess whether vaccine induced antibodies against surface antigens of M. ulcerans can protect against Buruli ulcer we formulated two surface vaccine candidate antigens, MUL_2232 and MUL_3720, as recombinant proteins with the synthetic Toll-like receptor 4 agonist glucopyranosyl lipid adjuvant-stable emulsion. The candidate vaccines elicited strong antibody responses without a strong bias towards a TH1 type cellular response, as indicated by the IgG2a to IgG1 ratio. Despite the cross-reactivity of the induced antibodies with the native antigens, no significant protection was observed against progression of an experimental M. ulcerans infection in a mouse footpad challenge model. Even though vaccine-induced antibodies have the potential to opsonise the extracellular bacilli they do not have a protective effect since infiltrating phagocytes might be killed by mycolactone before reaching the bacteria, as indicated by lack of viable infiltrates in the necrotic infection foci.

  7. Plasma-enhanced antibody immobilization for the development of a capillary-based carcinoembryonic antigen immunosensor using laser-induced fluorescence spectroscopy.

    Science.gov (United States)

    Yu, Qiaoling; Zhan, Xuefang; Liu, Kunping; Lv, Hao; Duan, Yixiang

    2013-05-07

    In this study, antibody immobilization using a microwave-induced H2O/Ar plasma pretreatment was achieved for the first time. Plasma was used to activate the surface of a capillary-based immunosensor by increasing the density of silicon hydroxyls and dangling bonds to ensure better silanization. The capture antibodies were covalently immobilized after the silanized surface reacted with glutaraldehyde and antibodies. A Cy3-labeled detection antibody was used in combination with the antigen captured by the immunosensor to complete the sandwich-type immunoassay, and the signals were measured using a laser-induced fluorescence system. Microwave-induced H2O/Ar plasma pretreatment of the carcinoembryonic antigen (CEA) immunosensor improved the antibody immobilization, and there was an obvious improvement in the linear detection range, i.e., 1 order of magnitude compared with a commercial enzyme-linked immunosorbent assay (ELISA). This novel immobilization method dramatically improved the detection limit (0.5 pmol/L CEA) and sensitivity. Assay validation studies indicated that the correlation coefficient reached 0.9978, and the relative standard deviations were Ar plasma was demonstrated to be a sensitive tool for CEA diagnostics.

  8. Neutralizing antibody responses in macaques induced by human immunodeficiency virus type 1 monovalent or trivalent envelope glycoproteins.

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    Gerald V Quinnan

    Full Text Available A major goal of efforts to develop a vaccine to prevent HIV-1 infection is induction of broadly cross-reactive neutralizing antibodies (bcnAb. In previous studies we have demonstrated induction of neutralizing antibodies that did cross-react among multiple primary and laboratory strains of HIV-1, but neutralized with limited potency. In the present study we tested the hypothesis that immunization with multiple HIV-1 envelope glycoproteins (Envs would result in a more potent and cross-reactive neutralizing response. One Env, CM243(N610Q, was selected on the basis of studies of the effects of single and multiple mutations of the four gp41 glycosylation sites. The other two Envs included R2 (subtype B and 14/00/4 (subtype F, both of which were obtained from donors with bcnAb. Rhesus monkeys were immunized using a prime boost regimen as in previous studies. Individual groups of monkeys were immunized with either one of the three Envs or all three. The single N610Q and N615Q mutations of CM243 Env did not disrupt protein secretion, processing into, or reactivity with mAbs, unlike other single or multiple deglycosylation mutations. In rabbit studies the N610Q mutation alone or in combination was associated with an enhanced neutralizing response against homologous and heterologous subtype E viruses. In the subsequent monkey study the response induced by the R2 Env regimen was equivalent to the trivalent regimen and superior to the other monovalent regimens against the virus panel used for testing. The 14/00/4 Env induced responses superior to CM243(N610Q. The results indicate that elimination of the glycosylation site near the gp41 loop results in enhanced immunogenicity, but that immunization of monkeys with these three distinct Envs was not more immunogenic than with one.

  9. Importance of Antibodies to Lipopolysaccharide in Natural and Vaccine-Induced Serum Bactericidal Activity against Neisseria meningitidis Group B▿†

    Science.gov (United States)

    Schmiel, Deborah H.; Moran, Elizabeth E.; Keiser, Paul B.; Brandt, Brenda L.; Zollinger, Wendell D.

    2011-01-01

    Analysis of the specificity of bactericidal antibodies in normal, convalescent, and postvaccination human sera is important in understanding human immunity to meningococcal infections and can aid in the design of an effective group B vaccine. A collection of human sera, including group C and group B convalescent-phase sera, normal sera with naturally occurring cross-reactive bactericidal activity, and some postvaccination sera, was analyzed to determine the specificity of cross-reactive bactericidal antibodies. Analysis of human sera using a bactericidal antibody depletion assay demonstrated that a significant portion of the bactericidal activity could be removed by purified lipopolysaccharide (LPS). LPS homologous to that expressed on the bactericidal test strain was most effective, but partial depletion by heterologous LPS suggested the presence of antibodies with various degrees of cross-reactivity. Binding of anti-L3,7 LPS bactericidal antibodies was affected by modification of the core structure, suggesting that these functional antibodies recognized epitopes consisting of both core structures and lacto-N-neotetraose (LNnT). When the target strain was grown with 5′-cytidinemonophospho-N-acetylneuraminic acid (CMP-NANA) to increase LPS sialylation, convalescent-phase serum bactericidal titers were decreased by only 2- to 4-fold, and most remaining bactericidal activity was still depleted by LPS. Highly sialylated LPS was ineffective in depleting bactericidal antibodies. We conclude that natural infections caused by strains expressing L3,7 LPS induce persistent, protective bactericidal antibodies and appear to be directed against nonsialylated bacterial epitopes. Additionally, subsets of these bactericidal antibodies are cross-reactive, binding to several different LPS immunotypes, which is a useful characteristic for an effective group B meningococcal vaccine antigen. PMID:21768280

  10. Monoclonal antibodies protect from Staphylococcal Enterotoxin K (SEK) induced toxic shock and sepsis by USA300 Staphylococcus aureus.

    Science.gov (United States)

    Aguilar, Jorge L; Varshney, Avanish K; Pechuan, Ximo; Dutta, Kaushik; Nosanchuk, Joshua D; Fries, Bettina C

    2017-08-18

    Staphylococcus aureus is a leading infectious cause of life-threatening disease in humans, yet there is currently no vaccine to combat this bacterium. The pathogenesis of S. aureus is mediated by a diverse array of protein toxins including a large family of secreted pyrogenic superantigens. Neutralization of superantigens, including SEB and TSST-1, has proven to be protective in several animal models of toxic shock and sepsis. We demonstrate, for the first time, that a far more prevalent staphylococcal superantigen, SEK, can also induce lethal shock in mice. Additionally, we describe monoclonal antibodies (mAbs) that inhibit SEK-induced mitogenicity as well as protect against SEK-induced lethality, and enhance survival from S. aureus septicemia in murine models. MAb-4G3 (IgG2b), mAb-5G2 (IgG1), and mAb-9H2 (IgG1), all inhibit SEK-induced proliferation and cytokine production of human immune cells. We then demonstrate that passive immunization with a combination of mAb-4G3 and mAb-5G4, 2 mAbs that do not compete for epitope(s) on SEK, significantly enhance survival in a murine model of SEK-induced toxic shock (p = 0.006). In the setting of sepsis, passive immunization with this combination of mAbs also significantly enhances survival in mice after challenge with CA-MRSA strain USA300 (p = 0.03). Furthermore, septic mice that received mAb treatment in conjunction with vancomycin exhibit less morbidity than mice treated with vancomycin alone. Taken together, these findings suggest that the contribution of SEK to S. aureus pathogenesis may be greater than previously appreciated, and that adjunctive therapy with passive immunotherapy against SEs may be beneficial.

  11. Sublingual injection of microparticles containing glycolipid ligands for NKT cells and subunit vaccines induces antibody responses in oral cavity.

    Science.gov (United States)

    DeLyria, Elizabeth S; Zhou, Dapeng; Lee, Jun Soo; Singh, Shailbala; Song, Wei; Li, Fenge; Sun, Qing; Lu, Hongzhou; Wu, Jinhui; Qiao, Qian; Hu, Yiqiao; Zhang, Guodong; Li, Chun; Sastry, K Jagannadha; Shen, Haifa

    2015-03-20

    Natural Killer T (NKT) cells are a unique type of innate immune cells which exert paradoxical roles in animal models through producing either Th1 or Th2 cytokines and activating dendritic cells. Alpha-galactosylceramide (αGalCer), a synthetic antigen for NKT cells, was found to be safe and immune stimulatory in cancer and hepatitis patients. We recently developed microparticle-formulated αGalCer, which is selectively presented by dendritic cells and macrophages, but not B cells, and thus can avoid the anergy of NKT cells. In this study, we have examined the immunogenicity of microparticles containing αGalCer and protein vaccine components through sublingual injection in mice. The results showed that sublingual injection of microparticles containing αGalCer and ovalbumin triggered IgG responses in serum (titer >1:100,000), which persisted for more than 3months. Microparticles containing ovalbumin alone also induced comparable level of IgG responses. However, immunoglobulin subclass analysis showed that sublingually injected microparticles containing αGalCer and ovalbumin induced 20 fold higher Th1 biased antibody (IgG2c) than microparticles containing OVA alone (1:20,000 as compared to 1:1000 titer). Sublingual injection of microparticles containing αGalCer and ovalbumin induced secretion of both IgG (titer >1:1000) and IgA (titer=1:80) in saliva secretion, while microparticles containing ovalbumin alone only induced secretion of IgG in saliva. Our results suggest that sublingual injection of microparticles and their subsequent trafficking to draining lymph nodes may induce adaptive immune responses in mucosal compartments. Ongoing studies are focused on the mechanism of antigen presentation and lymphocyte biology in the oral cavity, as well as the toxicity and efficacy of these candidate microparticles for future applications. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Cellular mechanism of primary anti-Thy-1 antibody responses in vitro induced by uniquely immunogenic thymocyte antigens.

    Science.gov (United States)

    Isobe, K I; Nakashima, I; Nagase, F; Kato, N; Mizoguchi, K; Kawashima, K; Lake, P

    1984-03-01

    Thy-1 antigens are the only cell membrane antigens known to be able to induce primary antibody responses in vitro. We have shown that antigens from the thymocytes of mice and rats were highly immunogenic in cultures of murine spleen cells for the induction of Thy-1.1-specific plaque-forming cell responses, whereas antigens from other tissues, including brains and bone marrow, were poorly immunogenic, if at all. The thymocyte-specific Thy-1 immunogenicity was carried by disrupted cell membranes, and the specific activity for inducing responses was closely linked to Thy-1. We then tried to determine the mechanism of anti-Thy-1 antibody responses in vitro that were induced by the uniquely immunogenic thymocyte antigens. The thymocyte Thy-1 antigens behaved as T cell-independent class 2 (TI-2) antigens: they induced responses in athymic nude mice but not in CBA/N mice with a B cell defect. The apparent TI-2 responses to thymocyte Thy-1 did, however, require Thy-1+ cells in the responder, similar to anti-DNP-Ficoll responses. The full development of the anti-Thy-1 responses required the participation of splenic adherent cells (SAC). Nevertheless, the mechanism of the SAC dependency of anti-Thy-1 responses did not involve antigen presentation to lymphocytes by antigen-pulsed SAC, which contrasted with the finding that the presentation of antigen by live SAC to lymphocytes was indispensable for responses to DNP-Ficoll. The poor Thy-1 responsiveness of SAC-depleted spleen cells was fully restored by the addition of soluble factors (IL 1-like molecules) released from SAC into the culture, which did not replace the SAC-requirement of responses to DNP-Ficoll. It was concluded from these results that Thy-1 or Thy-1-linked structures on thymocyte membranes have an intrinsic activity to directly signal either TI-2 B cells or immature T cells, or both, for activation in the presence of soluble factors released from adherent accessory cells. This conclusion is discussed in

  13. Hydralazine-induced anti-neutrophil cytoplasmic antibody-positive renal vasculitis presenting with a vasculitic syndrome, acute nephritis and a puzzling skin rash: a case report

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    Keasberry Justin

    2013-01-01

    Full Text Available Abstract Introduction Anti-neutrophil cytoplasmic antibody-associated vasculitis has been associated with many drugs and it is a relatively rare side effect of the antihypertensive drug hydralazine. The diagnosis and management of patients who have anti-neutrophil cytoplasmic antibody-associated vasculitis may be challenging because of its relative infrequency, variability of clinical expression and changing nomenclature. The spectrum of anti-neutrophil cytoplasmic antibody-associated vasculitis is wide and can be fatal. This case documents a 62-year-old woman who presented with hydralazine-induced anti-neutrophil cytoplasmic antibody-positive renal vasculitis with a puzzling cutaneous rash. Case presentation We report a rare case of hydralazine-induced anti-neutrophil cytoplasmic antibody-associated vasculitis in a 62-year-old Caucasian woman who presented with a vasculitic syndrome with a sore throat, mouth ulcers and otalgia after several months of constitutional symptoms. She then proceeded to develop a rash over her right lower limb. Clinically, the rash had features to suggest Sweet’s syndrome, but also had some appearances consistent with embolic phenomena and did not have the appearance of palpable purpure usually associated with cutaneous vasculitis. Differential diagnoses were hydralazine-associated Sweet’s syndrome, streptococcal-induced cutaneous eruption or an unrelated contact dermatitis. A midstream urine sample detected glomerular blood cells in the setting of anti-neutrophil cytoplasmic antibody-positive renal vasculitis and Streptococcus pyogenes bacteremia. A renal biopsy revealed a pauci-immune, focally necrotizing glomerulonephritis with small crescents. Her skin biopsy revealed a heavy neutrophil infiltrate involving the full thickness of the dermis with no evidence of a leucocytoclastic vasculitis, but was non-specific. She was initially commenced on intravenous lincomycin for her bloodstream infection and subsequently

  14. Hydralazine-induced anti-neutrophil cytoplasmic antibody-positive renal vasculitis presenting with a vasculitic syndrome, acute nephritis and a puzzling skin rash: a case report.

    Science.gov (United States)

    Keasberry, Justin; Frazier, Jeremy; Isbel, Nicole M; Van Eps, Carolyn L; Oliver, Kimberley; Mudge, David W

    2013-01-14

    Anti-neutrophil cytoplasmic antibody-associated vasculitis has been associated with many drugs and it is a relatively rare side effect of the antihypertensive drug hydralazine. The diagnosis and management of patients who have anti-neutrophil cytoplasmic antibody-associated vasculitis may be challenging because of its relative infrequency, variability of clinical expression and changing nomenclature. The spectrum of anti-neutrophil cytoplasmic antibody-associated vasculitis is wide and can be fatal. This case documents a 62-year-old woman who presented with hydralazine-induced anti-neutrophil cytoplasmic antibody-positive renal vasculitis with a puzzling cutaneous rash. We report a rare case of hydralazine-induced anti-neutrophil cytoplasmic antibody-associated vasculitis in a 62-year-old Caucasian woman who presented with a vasculitic syndrome with a sore throat, mouth ulcers and otalgia after several months of constitutional symptoms. She then proceeded to develop a rash over her right lower limb. Clinically, the rash had features to suggest Sweet's syndrome, but also had some appearances consistent with embolic phenomena and did not have the appearance of palpable purpure usually associated with cutaneous vasculitis. Differential diagnoses were hydralazine-associated Sweet's syndrome, streptococcal-induced cutaneous eruption or an unrelated contact dermatitis. A midstream urine sample detected glomerular blood cells in the setting of anti-neutrophil cytoplasmic antibody-positive renal vasculitis and Streptococcus pyogenes bacteremia. A renal biopsy revealed a pauci-immune, focally necrotizing glomerulonephritis with small crescents. Her skin biopsy revealed a heavy neutrophil infiltrate involving the full thickness of the dermis with no evidence of a leucocytoclastic vasculitis, but was non-specific. She was initially commenced on intravenous lincomycin for her bloodstream infection and subsequently commenced on immunosuppression after cessation of hydralazine

  15. Heavy-chain isotype patterns of human antibody-secreting cells induced by Haemophilus influenzae type b conjugate vaccines in relation to age and preimmunity

    DEFF Research Database (Denmark)

    Barington, T; Juul, Lars; Gyhrs, A

    1994-01-01

    The influence of preexisting immunity on the heavy-chain isotypes of circulating antibody-secreting cells (AbSC) induced by vaccination with Haemophilus influenzae type b (Hib) capsular polysaccharide (HibCP) coupled to tetanus toxoid (TT) or diphtheria toxoid (DT) and by vaccination with TT or DT...

  16. Bacterium-like particles supplemented with inactivated influenza antigen induce cross-protective influenza-specific antibody responses through intranasal administration

    NARCIS (Netherlands)

    de Haan, Aalzen; Haijema, Bert Jan; Voorn, Petra; Meijerhof, Tjarko; van Roosmalen, Maarten L.; Leenhouts, Kees

    2012-01-01

    Administration of influenza vaccines through the intranasal (IN) route forms an attractive alternative to conventional intramuscular (IM) injection. It is not only a better accepted form of vaccine administration but it also has the potential to induce, in addition to systemic antibodies, local

  17. Fungal melanin stimulates surfactant protein D-mediated opsonization of and host immune response to Aspergillus fumigatus spores.

    Science.gov (United States)

    Sze Wah Wong, Sarah; Rani, Manjusha; Dodagatta-Marri, Eswari; Ibrahim-Granet, Oumaima; Kishore, Uday; Bayry, Jagadeesh; Latgé, Jean-Paul; Sahu, Arvind; Madan, Taruna; Aimanianda, Vishukumar

    2018-02-05

    Surfactant protein D (SP-D), a C-type lectin and pattern-recognition soluble factor, plays an important role in immune surveillance to detect and eliminate human pulmonary pathogens. SPD has been shown to protect against infections with the most ubiquitous airborne fungal pathogen, Aspergillus fumigatus, but the fungal surface component(s) interacting with SP-D is unknown. Here, we show that SP-D binds to melanin pigment on the surface of A. fumigatus dormant spores (conidia). SP-D also exhibited an affinity to two cell-wall polysaccharides of A. fumigatus, galactomannan (GM) and galactosaminogalactan (GAG). The immunolabeling pattern of SP-D was punctate on the conidial surface and was uniform on germinating conidia, in accordance with the localization of melanin, GM, and GAG. We also found that the collagen-like domain of SP-D is involved in its interaction with melanin, whereas its carbohydrate-recognition domain recognized GM and GAG. Unlike unopsonized conidia, SPD-opsonized conidia were phagocytosed more efficiently and stimulated the secretion of proinflammatory cytokines by human monocytederived macrophages. Further, SP-D -/- mice challenged intranasally with wild-type conidia or melanin ghosts (i.e. hollow melanin spheres) displayed significantly reduced proinflammatory cytokines in the lung compared with wild-type mice. In summary, SP-D binds to melanin present on the dormant A. fumigatus conidial surface, facilitates conidial phagocytosis, and stimulates the host immune response. Copyright © 2018, The American Society for Biochemistry and Molecular Biology.

  18. The respiratory syncytial virus G protein conserved domain induces a persistent and protective antibody response in rodents.

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    Thien N Nguyen

    Full Text Available Respiratory syncytial virus (RSV is an important cause of severe upper and lower respiratory disease in infants and in the elderly. There are 2 main RSV subtypes A and B. A recombinant vaccine was designed based on the central domain of the RSV-A attachment G protein which we had previously named G2Na (aa130-230. Here we evaluated immunogenicity, persistence of antibody (Ab response and protective efficacy induced in rodents by: (i G2Na fused to DT (Diphtheria toxin fragments in cotton rats. DT fusion did not potentiate neutralizing Ab responses against RSV-A or cross-reactivity to RSV-B. (ii G2Nb (aa130-230 of the RSV-B G protein either fused to, or admixed with G2Na. G2Nb did not induce RSV-B-reactive Ab responses. (iii G2Na at low doses. Two injections of 3 µg G2Na in Alum were sufficient to induce protective immune responses in mouse lungs, preventing RSV-A and greatly reducing RSV-B infections. In cotton rats, G2Na-induced RSV-reactive Ab and protective immunity against RSV-A challenge that persisted for at least 24 weeks. (iv injecting RSV primed mice with a single dose of G2Na/Alum or G2Na/PLGA [poly(D,L-lactide-co-glycolide]. Despite the presence of pre-existing RSV-specific Abs, these formulations effectively boosted anti-RSV Ab titres and increased Ab titres persisted for at least 21 weeks. Affinity maturation of these Abs increased from day 28 to day 148. These data indicate that G2Na has potential as a component of an RSV vaccine formulation.

  19. Pneumococcal Polysaccharide Abrogates Conjugate-Induced Germinal Center Reaction and Depletes Antibody Secreting Cell Pool, Causing Hyporesponsiveness

    Science.gov (United States)

    Bjarnarson, Stefania P.; Benonisson, Hreinn; Del Giudice, Giuseppe; Jonsdottir, Ingileif

    2013-01-01

    Background Plain pneumococcal polysaccharide (PPS) booster administered during second year of life has been shown to cause hyporesponsiveness. We assessed the effects of PPS booster on splenic memory B cell responses and persistence of PPS-specific long-lived plasma cells in the bone marrow (BM). Methods Neonatal mice were primed subcutanously (s.c.) or intranasally (i.n.) with pneumococcal conjugate (Pnc1-TT) and the adjuvant LT-K63, and boosted with PPS+LT-K63 or saline 1, 2 or 3 times with 16 day intervals. Seven days after each booster, spleens were removed, germinal centers (GC), IgM+, IgG+ follicles and PPS-specific antibody secreting cells (AbSC) in spleen and BM enumerated. Results PPS booster s.c., but not i.n., compromised the Pnc1-TT-induced PPS-specific Abs by abrogating the Pnc1-TT-induced GC reaction and depleting PPS-specific AbSCs in spleen and limiting their homing to the BM. There was no difference in the frequency of PPS-specific AbSCs in spleen and BM between mice that received 1, 2 or 3 PPS boosters s.c.. Repeated PPS+LT-K63 booster i.n. reduced the frequency of PPS-specific IgG+ AbSCs in BM. Conclusions PPS booster-induced hyporesponsiveness is caused by abrogation of conjugate-induced GC reaction and depletion of PPS-specific IgG+ AbSCs resulting in no homing of new PPS-specific long-lived plasma cells to the BM or survival. These results should be taken into account in design of vaccination schedules where polysaccharides are being considered. PMID:24069152

  20. A heterologous prime-boost Ebola virus vaccine regimen induces durable neutralizing antibody response and prevents Ebola virus-like particle entry in mice.

    Science.gov (United States)

    Chen, Tan; Li, Dapeng; Song, Yufeng; Yang, Xi; Liu, Qingwei; Jin, Xia; Zhou, Dongming; Huang, Zhong

    2017-09-01

    Ebola virus (EBOV) is one of the most virulent pathogens known to humans. Neutralizing antibodies play a major role in the protection against EBOV infections. Thus, an EBOV vaccine capable of inducing a long-lasting neutralizing antibody response is highly desirable. We report here that a heterologous prime-boost vaccine regimen can elicit durable EBOV-neutralizing antibody response in mice. A chimpanzee serotype 7 adenovirus expressing EBOV GP (denoted AdC7-GP) was generated and used for priming. A truncated version of EBOV GP1 protein (denoted GP1t) was produced at high levels in Drosophila S2 cells and used for boosting. Mouse immunization studies showed that the AdC7-GP prime/GP1t boost vaccine regimen was more potent in eliciting neutralizing antibodies than either the AdC7-GP or GP1t alone. Neutralizing antibodies induced by the heterologous prime-boost regimen sustained at high titers for at least 18 weeks after immunization. Significantly, in vivo challenge studies revealed that the entry of reporter EBOV-like particles was efficiently blocked in mice receiving the heterologous prime-boost regimen even at 18 weeks after the final dose of immunization. These results suggest that this novel AdC7-GP prime/GP1t boost regimen represents an EBOV vaccine approach capable of establishing long-term protection, and therefore warrants further development. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Heterogeneous stock mice are susceptible to encephalomyelitis and antibody-initiated arthritis but not to collagen- and G6PI-induced arthritis.

    Science.gov (United States)

    Klaczkowska, D; Raposo, B; Nandakumar, K S

    2011-01-01

    The strategy of using heterogeneous stock (HS) mice has proven to be successful in fine mapping of quantitative trait loci in complex diseases. However, whether these mice can be used for arthritis, encephalomyelitis and autoimmune phenotypes has not been addressed. Here, we screened the Northport HS mice for arthritis phenotypes using three different models: collagen-induced arthritis (CIA), using rat, bovine or chicken collagen type II (CII); recombinant human glucose-6-phosphate isomerase (G6PI)-induced arthritis; and collagen antibody-induced arthritis (CAIA). Irrespective of the origin of collagen, we found HS mice to be fairly resistant to CIA and G6PI-induced arthritis, despite the development of antibodies against the respective antigens. On the other hand, HS mice were found to be susceptible for CAIA. Similarly, these mice developed encephalomyelitis (EAE) induced either with mouse or rat spinal cord homogenate (SCH), or with recombinant rat myelin oligodendrocyte glycoprotein, with elevated antibody levels against CNS proteins. Accordingly, we conclude that the use of HS mice for fine mapping and positional cloning of gene(s) involved in CAIA and EAE is possible, but not for collagen- and G6PI-induced arthritis. © 2011 The Authors. Scandinavian Journal of Immunology © 2011 Blackwell Publishing Ltd.

  2. Advanced Glycation End Products (AGEs Antibody Protects Against AGEs-induced Apoptosis and NF-ĸB p65 Subunit Overexpression in Rat Glomerular Culture

    Directory of Open Access Journals (Sweden)

    Oktavia Rahayu Adianingsih

    2016-11-01

    Full Text Available Advanced glycation end products (AGEs have been thought to be a major cause of diabetic nephropathy (DN. The mechanisms underlying the involvement of AGEs antibody in diabetic nephropathy are not fully understood. The present study was designed to investigate the protective effect of AGEs antibody on AGEs-induced glomerular damage. Isolated glomeruli were pre-incubated either with 10 µg/mL polyclonal anti-AGEs antibody (AGE-pAb or monoclonal anti-Nɜ -carboxymethyl-lysine antibody (CML-mAb as a model of AGEs antibody to block interaction of AGEs with receptor for AGEs (RAGE and incubated afterwards either with 100 µg/mL bovine serum albumin (BSA or AGE-modified bovine serum albumin (AGE-BSA for 48 h. Annexin V/nephrin doublestaining was performed to determine apoptosis. Using immunofluorescence, we found that administration of AGE-BSA not only significantly increased glomerular cells apoptosis and nuclear factor kappa B (NF-ĸB p65 expression, but also reduced expression of nephrin, an important structural and signal molecule of podocytes slit diaphragm. Blocking the interaction of AGE-RAGE with AGEs antibody significantly protected glomerular cells from AGEs-induced apoptosis and NF-ĸB p65 overexpression. We found that AGE-pAb conferred superior protective effect compared with CmL-mAb for the same reduction in apoptosis and NF-ĸB p65 expression. In sharp contrast, CmL-mAb led to preserve expression of podocytes nephrin better than AGE-pAb. These results demonstrate that the antibody against AGEs may be beneficial for preventing the glomerular damage in DN.

  3. Oral Vaccination with the Porcine Rotavirus VP4 Outer Capsid Protein Expressed by Lactococcus lactis Induces Specific Antibody Production

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    Yi-jing Li

    2010-01-01

    Full Text Available The objective of this study to design a delivery system resistant to the gastrointestinal environment for oral vaccine against porcine rotavirus. Lactococcus lactis NZ9000 was transformed with segments of vP4 of the porcine rotavirus inserted into the pNZ8112 surface-expression vector, and a recombinant L. lactis expressing VP4 protein was constructed. An approximately 27 kDa VP4 protein was confirmed by SDS-PAGE , Western blot and immunostaining analysis. BALB/c mice were immunized orally with VP4-expression recombinant L. lactis and cellular, mucosal and systemic humoral immune responses were examined. Specific anti-VP4 secretory IgA and IgG were found in feces, ophthalmic and vaginal washes and in serum. The induced antibodies demonstrated neutralizing effects on porcine rotavirus infection on MA104 cells. Our findings suggest that oral immunization with VP4-expressing L. lactis induced both specific local and systemic humoral and cellular immune responses in mice.

  4. Novel ISCOMs from Quillaja brasiliensis saponins induce mucosal and systemic antibody production, T-cell responses and improved antigen uptake.

    Science.gov (United States)

    Cibulski, Samuel Paulo; Mourglia-Ettlin, Gustavo; Teixeira, Thais Fumaco; Quirici, Lenora; Roehe, Paulo Michel; Ferreira, Fernando; Silveira, Fernando

    2016-02-24

    In the last decades, significant efforts have been dedicated to the search for novel vaccine adjuvants. In this regard, saponins and its formulations as "immunostimulating complexes" (ISCOMs) have shown to be capable of stimulating potent humoral and cellular immune responses, enhanced cytokine production and activation of cytotoxic T cells. The immunological activity of ISCOMs formulated with a saponin fraction extracted from Quillaja brasiliensis (QB-90 fraction) as an alternative to classical ISCOMs based on Quil A(®) (IQA) is presented here. The ISCOMs prepared with QB-90, named IQB-90, typically consist of 40-50 nm, spherical, cage-like particles, built up by QB-90, cholesterol, phospholipids and antigen (ovalbumin, OVA). These nanoparticles were efficiently uptaken in vitro by murine bone marrow-derived dendritic cells. Subcutaneously inoculated IQB-90 induced strong serum antibody responses encompassing specific IgG1 and IgG2a, robust DTH reactions, significant T cell proliferation and increases in Th1 (IFN-γ and IL-2) cytokine responses. Intranasally delivered IQB-90 elicited serum IgG and IgG1, and mucosal IgA responses at distal systemic sites (nasal passages, large intestine and vaginal lumen). These results indicate that IQB-90 is a promising alternative to classic ISCOMs as vaccine adjuvants, capable of enhancing humoral and cellular immunity to levels comparable to those induced by ISCOMs manufactured with Quillaja saponaria saponins. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. A Rationally Designed TNF-α Epitope-Scaffold Immunogen Induces Sustained Antibody Response and Alleviates Collagen-Induced Arthritis in Mice.

    Directory of Open Access Journals (Sweden)

    Li Zhang

    Full Text Available The TNF-α biological inhibitors have significantly improved the clinical outcomes of many autoimmune diseases, in particular rheumatoid arthritis. However, the practical uses are limited due to high costs and the risk of anti-drug antibody responses. Attempts to develop anti-TNF-α vaccines have generated encouraging data in animal models, however, data from clinical trials have not met expectations. In present study, we designed a TNF-α epitope-scaffold immunogen DTNF7 using the transmembrane domain of diphtheria toxin, named DTT as a scaffold. Molecular dynamics simulation shows that the grafted TNF-α epitope is entirely surface-exposed and presented in a native-like conformation while the rigid helical structure of DTT is minimally perturbed, thereby rendering the immunogen highly stable. Immunization of mice with alum formulated DTNF7 induced humoral responses against native TNF-α, and the antibody titer was sustained for more than 6 months, which supports a role of the universal CD4 T cell epitopes of DTT in breaking self-immune tolerance. In a mouse model of rheumatoid arthritis, DTNF7-alum vaccination markedly delayed the onset of collagen-induced arthritis, and reduced incidence as well as clinical score. DTT is presumed safe as an epitope carrier because a catalytic inactive mutant of diphtheria toxin, CRM197 has good clinical safety records as an active vaccine component. Taken all together, we show that DTT-based epitope vaccine is a promising strategy for prevention and treatment of autoimmune diseases.

  6. Formalin-inactivated EV71 vaccine candidate induced cross-neutralizing antibody against subgenotypes B1, B4, B5 and C4A in adult volunteers.

    Directory of Open Access Journals (Sweden)

    Ai-Hsiang Chou

    Full Text Available Enterovirus 71 (EV71 has caused several epidemics of hand, foot and mouth diseases (HFMD in Asia. No effective EV71 vaccine is available. A randomized and open-label phase I clinical study registered with ClinicalTrials.gov #NCT01268787, aims to evaluate the safety, reactogenicity and immunogenicity of a formalin-inactivated EV71 vaccine candidate (EV71vac at 5- and 10-µg doses. In this study we report the cross-neutralizing antibody responses from each volunteer against different subgenotypes of EV71 and CVA16.Sixty eligible healthy adults were recruited and vaccinated. Blood samples were obtained on day 0, 21 and 42 and tested against B1, B4, B5, C2, C4A, C4B and CVA16 for cross-neutralizing antibody responses.The immunogenicity of both 5- and 10- µg doses were found to be very similar. Approximately 45% of the participants had 4-fold increase in Nt, but there was no further increase in Nt after the second dose. EV71vac induced very strong cross-neutralizing antibody responses in >85% of volunteers without pre-existing Nt against subgenotype B1, B5 and C4A. EV71vac elicited weak cross-neutralizing antibody responses (∼20% of participants against a C4B and Coxsackie virus A16. Over 90% of vaccinated volunteers did not develop cross-neutralizing antibody responses (Nt<8 against a C2 strain. EV71vac can boost and significantly enhance the neutralizing antibody responses in volunteers who already had pre-vaccination antibodies against EV71 and/or CVA16.EV71vac is efficient in eliciting cross-neutralizing antibody responses against EV71 subgenotypes B1, B4, B5, and C4A, and provides the rationale for its evaluation in phase II clinical trials.ClinicalTrials.gov NCT01268787.

  7. Nanoporous Microneedle Arrays Effectively Induce Antibody Responses against Diphtheria and Tetanus Toxoid

    Science.gov (United States)

    de Groot, Anne Marit; Platteel, Anouk C. M.; Kuijt, Nico; van Kooten, Peter J. S.; Vos, Pieter Jan; Sijts, Alice J. A. M.; van der Maaden, Koen

    2017-01-01

    The skin is immunologically very potent because of the high number of antigen-presenting cells in the dermis and epidermis, and is therefore considered to be very suitable for vaccination. However, the skin’s physical barrier, the stratum corneum, prevents foreign substances, including vaccines, from entering the skin. Microneedles, which are needle-like structures with dimensions in the micrometer range, form a relatively new approach to circumvent the stratum corneum, allowing for minimally invasive and pain-free vaccination. In this study, we tested ceramic nanoporous microneedle arrays (npMNAs), representing a novel microneedle-based drug delivery technology, for their ability to deliver the subunit vaccines diphtheria toxoid (DT) and tetanus toxoid (TT) intradermally. First, the piercing ability of the ceramic (alumina) npMNAs, which contained over 100 microneedles per array, a length of 475 µm, and an average pore size of 80 nm, was evaluated in mouse skin. Then, the hydrodynamic diameters of DT and TT and the loading of DT, TT, and imiquimod into, and subsequent release from the npMNAs were assessed in vitro. It was shown that DT and TT were successfully loaded into the tips of the ceramic nanoporous microneedles, and by using near-infrared fluorescently labeled antigens, we found that DT and TT were released following piercing of the antigen-loaded npMNAs into ex vivo murine skin. Finally, the application of DT- and TT-loaded npMNAs onto mouse skin in vivo led to the induction of antigen-specific antibodies, with titers similar to those obtained upon subcutaneous immunization with a similar dose. In conclusion, we show for the first time, the potential of npMNAs for intradermal (ID) immunization with subunit vaccines, which opens possibilities for future ID vaccination designs. PMID:29375544

  8. Nanoporous Microneedle Arrays Effectively Induce Antibody Responses against Diphtheria and Tetanus Toxoid.

    Science.gov (United States)

    de Groot, Anne Marit; Platteel, Anouk C M; Kuijt, Nico; van Kooten, Peter J S; Vos, Pieter Jan; Sijts, Alice J A M; van der Maaden, Koen

    2017-01-01

    The skin is immunologically very potent because of the high number of antigen-presenting cells in the dermis and epidermis, and is therefore considered to be very suitable for vaccination. However, the skin's physical barrier, the stratum corneum, prevents foreign substances, including vaccines, from entering the skin. Microneedles, which are needle-like structures with dimensions in the micrometer range, form a relatively new approach to circumvent the stratum corneum, allowing for minimally invasive and pain-free vaccination. In this study, we tested ceramic nanoporous microneedle arrays (npMNAs), representing a novel microneedle-based drug delivery technology, for their ability to deliver the subunit vaccines diphtheria toxoid (DT) and tetanus toxoid (TT) intradermally. First, the piercing ability of the ceramic (alumina) npMNAs, which contained over 100 microneedles per array, a length of 475 µm, and an average pore size of 80 nm, was evaluated in mouse skin. Then, the hydrodynamic diameters of DT and TT and the loading of DT, TT, and imiquimod into, and subsequent release from the npMNAs were assessed in vitro . It was shown that DT and TT were successfully loaded into the tips of the ceramic nanoporous microneedles, and by using near-infrared fluorescently labeled antigens, we found that DT and TT were released following piercing of the antigen-loaded npMNAs into ex vivo murine skin. Finally, the application of DT- and TT-loaded npMNAs onto mouse skin in vivo led to the induction of antigen-specific antibodies, with titers similar to those obtained upon subcutaneous immunization with a similar dose. In conclusion, we show for the first time, the potential of npMNAs for intradermal (ID) immunization with subunit vaccines, which opens possibilities for future ID vaccination designs.

  9. Nanoporous Microneedle Arrays Effectively Induce Antibody Responses against Diphtheria and Tetanus Toxoid

    Directory of Open Access Journals (Sweden)

    Anne Marit de Groot

    2017-12-01

    Full Text Available The skin is immunologically very potent because of the high number of antigen-presenting cells in the dermis and epidermis, and is therefore considered to be very suitable for vaccination. However, the skin’s physical barrier, the stratum corneum, prevents foreign substances, including vaccines, from entering the skin. Microneedles, which are needle-like structures with dimensions in the micrometer range, form a relatively new approach to circumvent the stratum corneum, allowing for minimally invasive and pain-free vaccination. In this study, we tested ceramic nanoporous microneedle arrays (npMNAs, representing a novel microneedle-based drug delivery technology, for their ability to deliver the subunit vaccines diphtheria toxoid (DT and tetanus toxoid (TT intradermally. First, the piercing ability of the ceramic (alumina npMNAs, which contained over 100 microneedles per array, a length of 475 µm, and an average pore size of 80 nm, was evaluated in mouse skin. Then, the hydrodynamic diameters of DT and TT and the loading of DT, TT, and imiquimod into, and subsequent release from the npMNAs were assessed in vitro. It was shown that DT and TT were successfully loaded into the tips of the ceramic nanoporous microneedles, and by using near-infrared fluorescently labeled antigens, we found that DT and TT were released following piercing of the antigen-loaded npMNAs into ex vivo murine skin. Finally, the application of DT- and TT-loaded npMNAs onto mouse skin in vivo led to the induction of antigen-specific antibodies, with titers similar to those obtained upon subcutaneous immunization with a similar dose. In conclusion, we show for the first time, the potential of npMNAs for intradermal (ID immunization with subunit vaccines, which opens possibilities for future ID vaccination designs.

  10. Anticitrullinated Protein Antibodies Induce Inflammatory Gene Expression Profile in Peripheral Blood Cells from CCP-positive Patients with RA.

    Science.gov (United States)

    Gertel, Smadar; Karmon, Gidi; Szarka, Eszter; Shovman, Ora; Houri-Levi, Esther; Mozes, Edna; Shoenfeld, Yehuda; Amital, Howard

    2018-03-01

    Anticitrullinated protein antibodies (ACPA) have major diagnostic significance in rheumatoid arthritis (RA). ACPA are directed against different citrullinated antigens, including filaggrin, fibrinogen, vimentin, and collagen. The presence of ACPA is associated with joint damage and extraarticular manifestations, suggesting that ACPA may have a significant role in the pathogenesis of RA. To verify the effect of ACPA on RA-immune cells, peripheral blood mononuclear cells (PBMC) from cyclic citrullinated peptide (CCP)-positive patients with RA and healthy controls were cocultured in vitro with ACPA. ACPA-positive stained cells were analyzed by flow cytometry and the effect of ACPA on mRNA expression levels was evaluated by real-time PCR. We tested whether the stimulatory effects induced by ACPA could be inhibited by the addition of a new multiepitope citrullinated peptide (Cit-ME). We found that ACPA bind specifically to PBMC from CCP-positive patients with RA through the Fab portion. ACPA induce upregulation of pathogenic cytokine expression (4- to 13-fold increase) in PBMC derived from CCP-positive patients with RA. Moreover, ACPA upregulated IL-1β and IL-6 mRNA expression levels by 10- and 6-fold, respectively, compared to control IgG. Cit-ME, a genuine ligand of ACPA, inhibited the ACPA-induced upregulation of IL-1β and IL-6 by 30%. ACPA bind to a limited percentage of PBMC and upregulate inflammatory cytokine expression, suggesting that ACPA is involved in RA pathogenesis. Targeting ACPA to decrease their pathogenic effects might provide a novel direction in developing therapeutic strategies for RA.

  11. Prevention of carrageenan-induced pleurisy in mice by anti-CD30 ligand monoclonal antibody

    DEFF Research Database (Denmark)

    Di Paola, Rosanna; Di Marco, Roberto; Mazzon, Emanuela

    2004-01-01

    CD30 ligand (CD30L) and its receptor CD30 are members of the tumor necrosis factor (TNF) and TNF receptor superfamilies that play a major role in inflammation and immune regulation. To gain insight into the in vivo role of CD30L/CD30 in inflammatory diseases, we have used carrageenan (CAR......)-induced pleurisy in mice, a preclinical model of airway inflammation where type 1 proinflammatory cytokines such as interleukin (IL)-1 and TNF-alpha play a key pathogenic role. The data show that prophylactic treatment with anti-CD30L mAb markedly reduces both laboratory and histological signs of CAR...

  12. Comparison of the cross-antibody response induced in sheep by inactivated bovine viral diarrhoea virus 1 and Hobi-like pestivirus.

    Science.gov (United States)

    Decaro, Nicola; Mari, Viviana; Sciarretta, Rossana; Lucente, Maria Stella; Camero, Michele; Losurdo, Michele; Larocca, Vittorio; Colao, Valeriana; Cavaliere, Nicola; Lovero, Angela; Lorusso, Eleonora; Buonavoglia, Canio

    2013-06-01

    Hobi-like pestivirus, a new tentative species within genus Pestivirus, was firstly detected in foetal bovine serum batches and later associated to respiratory distress and reproductive failures in cattle. In the present study, the cross-antibody response between bovine viral diarrhoea virus 1 (BVDV-1) and the emerging pestivirus was evaluated in the sheep model. Ten sheep were immunised against BVDV-1 or Hobi-like pestivirus using inactivated preparations and the induced antibody responses were evaluated against the homologous and heterologous viruses. The results showed that heterologous antibody titres were significantly lower than the homologous ones, thus suggesting the need to develop specific vaccines against the emerging pestiviral species. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. The Effect of Induced Antibodies with Respect to Neutralization, Clearance Rate and Functional Activity in a Rabbit/Infliximab Model

    DEFF Research Database (Denmark)

    Henriksen, Maiken Lumby; Søgaard Teisner, Ane; Kjeldsen, Jens

    2016-01-01

    BACKGROUND: Therapeutic antibodies are a developing field for treatment of an expanding number of inflammatory diseases, including Crohn's disease. Treatment with monoclonal antibodies is frequently hampered by development of anti-drug antibodies (ADAs) that may compromise the treatment. MATERIALS...... AND METHODS: We addressed this issue in a rabbit model of treatment with the anti-tumor-necrosis factor alpha (TNFα) antibody, infliximab (IFX). We developed an inhibition ELISA to selectively measure absolute concentrations of neutralizing antibodies and another ELISA for measuring the concentration...... of functional IFX in the circulation. RESULTS: We found that the concentration of functional IFX was inversely proportional to the concentration of neutralizing antibodies. CONCLUSION: Administration of IFX to rabbits showed diversity in immune responses/tolerance toward IFX, corresponding to responses observed...

  14. The Effect of Induced Antibodies with Respect to Neutralization, Clearance Rate and Functional Activity in a Rabbit/Infliximab Model

    DEFF Research Database (Denmark)

    Henriksen, Maiken Lumby; Teisner, Ane; Kjeldsen, Jens

    2016-01-01

    Background: Therapeutic antibodies are a developing field for treatment of an expanding number of inflammatory diseases, including Crohn's disease. Treatment with monoclonal antibodies is frequently hampered by development of anti-drug antibodies (ADAs) that may compromise the treatment. Materials...... and Methods: We addressed this issue in a rabbit model of treatment with the anti-tumor-necrosis factor alpha (TNF) antibody, infliximab (IFX). We developed an inhibition ELISA to selectively measure absolute concentrations of neutralizing antibodies and another ELISA for measuring the concentration...... of functional IFX in the circulation. Results: We found that the concentration of functional IFX was inversely proportional to the concentration of neutralizing antibodies. Conclusion: Administration of IFX to rabbits showed diversity in immune responses/tolerance toward IFX, corresponding to responses observed...

  15. 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.

  16. Presence of common idiotypes on antibodies induced by glutamic acid-lysine-containing terpolymers in responder and nonresponder mice with the Ig-1b heavy chain allotype.

    Science.gov (United States)

    Kipps, T J; Benacerraf, B; Dorf, M E

    1977-12-01

    A B10.A (5R) responder mouse to the random linear terpolymer, poly--(Glu, Lys, Phe), GLphi, can produce immunoglobulins which bind poly-L (Glu, Lys), GL, that share idiotypic determinants with GL-binding antibodies produced by other members of the same strain. Expression of these common idiotypic determinants, termed BGL, is independent of the H-2 halotype and closely linked to the Ig-lb heavy chain allotype. Moreover, nonresponder mice with the Ig-lb heavy chain allotype, when immunized with GLphi that has been chemically coupled to an immunogenic carrier, chicken IgG, can produce GL-binding antibodies that share BGL idiotypic specificities with anti-GLphi antibodies produced by responder animals. Also, the responses to other GL-containing polymers, such as poly-L (Glu, Lys, Ala) and poly-L (Glu, Lys, Pro), which are under the control of distinct Ir genes, can stimulate the production of GL-binding antibodies that share common BGL idiotypic determinants with antibodies induced with GLphi. These findings are discussed with respect to their implications concerning the mechanism(s) of Ir gene control.

  17. Original paper Assessment of the level of vaccine-induced anti-HBs antibodies in children with inflammatory systemic connective tissue diseases treated with immunosuppression

    Directory of Open Access Journals (Sweden)

    Izabela Szczygielska

    2015-05-01

    Full Text Available Objectives : Protective vaccinations are the most effective method of prevention of type B virus hepatitis. The aim of the study was to determine whether in children receiving immunosuppressive therapy due to inflammatory systemic connective tissue diseases the protective concentration of the anti-HBs antibodies produced after vaccination against type B virus hepatitis in infancy is maintained. Material and methods : The concentration of anti-HBs antibodies was assessed in the sera of 50 children with inflammatory connective tissue diseases – 37 girls (74% and 13 boys (26%, aged 1.5–17.5 years – during the immunosuppressive treatment, which lasted at least 6 months. The control group consisted of 50 healthy children – 28 girls (56% and 22 boys (44% aged 2–17 years. All children were vaccinated in infancy with Engerix B vaccine according to the 0–1–6 months schedule. The antibody concentration of ≥ 10 mIU/ml in patients is regarded as protective. Results: No protective antibody concentrations were found in 25 cases (50% in the group of diseased children and only in 2 children in the control group (4%. Conclusions : The concentration of vaccine-induced antibodies should be assessed in children with inflammatory systemic connective tissue diseases and, in case of the absence of a protective concentration, revaccination should be started. The use of glucocorticosteroids, synthetic and biological disease-modifying antirheumatic drugs is no contraindication to vaccination against hepatitis B.

  18. Antibody-dependent cell-mediated cytotoxicity can be induced by MUC1 peptide vaccination of breast cancer patients.

    Science.gov (United States)

    Snijdewint, F G; von Mensdorff-Pouilly, S; Karuntu-Wanamarta, A H; Verstraeten, A A; Livingston, P O; Hilgers, J; Kenemans, P

    2001-07-01

    Human polymorphic epithelial mucin (PEM, MUC1) is a high molecular weight transmembrane glycoprotein expressed on the apical cell surface of glandular epithelium and is over-expressed and hypo-glycosylated in adenocarcinomas. The extracellular part of the molecule consists mainly of a variable number of 20 amino acid repeats that contain cryptic epitopes exposed in malignancy. The objective of our study was to determine whether humanized MUC1 MAbs and Abs induced by vaccination of breast cancer patients with MUC1 peptides can effect an antibody-dependent cell-mediated cytotoxicity (ADCC). An in vitro assay has been set up in which the breast tumor cell line ZR-75-1 is used as target and PBMC of healthy donors as effector cells. Different target and effector cells, as well as various MUC1 MAbs were tested to optimize the efficacy of the in vitro assay. The humanized MAb HuHMFG-1, which recognizes the PDTR sequence in the MUC1 tandem repeat, induced a strong cell-mediated cytotoxicity. Nine MUC1-expressing tumor cell lines, including 3 bone marrow-derived cell lines, as well as 2 MUC1-transfected cell lines were susceptible to different extent to MUC1 Ab-dependent killing. Large variations in the killing capacity of PBMC from healthy donors were found. The NK cells were the essential effector cells for the MUC1 Ab-dependent killing. Plasma samples with induced high levels of MUC1 Ab were obtained from breast cancer patients repeatedly immunized with a KLH-conjugated 33-mer or 106-mer MUC1 tandem repeat. Pre- and post-vaccinated plasma samples of these patients were compared in the ADCC assay and it could be clearly demonstrated that the induced MUC1 Abs can effect tumor cell killing. MUC1 Ab-dependent cell-mediated tumor cell killing may occur in vivo and the ADCC assay can be applied to monitor MUC1 vaccination trials. Copyright 2001 Wiley-Liss, Inc.

  19. A cross-reacting material CRM197 conjugate vaccine induces diphtheria toxin neutralizing antibody response in children and adolescents infected or not with HIV.

    Science.gov (United States)

    Silva, Giselle P; Santos, Rafaela S; Pereira-Manfro, Wânia F; Ferreira, Bianca; Barreto, Daniella M; Frota, Ana Cristina C; Hofer, Cristina B; Milagres, Lucimar G

    2017-07-05

    Anti-diphtheria antibody levels decrease with aging, and frequent booster vaccinations are required to maintain herd immunity. We analyzed the diphtheria toxin neutralizing antibody (DT-Nab) response induced by a conjugate vaccine (meningococcal C polysaccharide-CRM 197 ) in HIV-vertically infected (HI) children and adolescents and healthy controls (HC) with matched age. We report the association of DT-Nab with the bactericidal antibodies to serogroup C meningococcus (MenC). Before vaccination, 21 HI patients (50%) had no protection against diphtheria (≤0.01IU/ml of antibody) and only 8 (19%) showed complete protection (≥0.1IU/ml). About half of the HC (56%) had complete protection before immunization and 6 subjects (12%) had no protection against diphtheria. After one and two vaccine injections, 96% of HC and 64% of HI vaccinees, respectively, showed full protection against diphtheria. These data indicate that CRM 197 was able to induce primary and/or booster response in both groups of individuals. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. An oral Aujeszky's disease vaccine (YS-400) induces neutralizing antibody in pigs.

    Science.gov (United States)

    Yang, Dong-Kun; Kim, Ha-Hyun; Choi, Sung-Suk; Hyun, Bang-Hun; Song, Jae-Young

    2016-07-01

    Aujeszky's disease (AD) is an economically important disease affecting both wild and domestic pigs of the species Sus scrofa. A previous study yielded serological evidence of AD in Korean wild boars, which could spread AD to other animals. A new Aujeszky's disease virus (ADV) bait vaccine is required to prevent AD outbreaks in swine. In the present study, we investigated the safety and immunogenicity of a gE-deleted marker vaccine, strain YS-400, in young domestic pigs. The YS-400 strain was propagated in Vero cells, and the trial ADV bait vaccine (a vaccine blister in a matrix including an attractant) was prepared. Pigs were orally immunized with the vaccine (2 mL, 10(7.5) TCID50/mL) delivered using a syringe or in the bait vaccine. The animals were observed for 9 weeks after vaccination, and immunogenicity was assessed using a virus neutralization (VN) test and enzyme linked immunosorbent assay. The YS-400 strain was non-pathogenic to pigs when given orally and induced high VN titers (1:32-1:128) 6 weeks post-administration. Of the pigs given the ADV bait vaccine twice or three times, 40% were seropositive by 2 weeks, and 100% were seropositive by 7 weeks after the first dose. Pigs that consumed the AD bait vaccine three times developed VN titers that were slightly higher than those of pigs given the vaccine twice. Domestic pigs given the trial ADV bait vaccine exhibited no adverse effects and developed high VN titers against ADV, indicating that the YS-400 strain is safe and can prevent ADV infection in domestic pigs.

  1. Using molecular principal axes for structural comparison: determining the tertiary changes of a FAB antibody domain induced by antigenic binding

    Directory of Open Access Journals (Sweden)

    Silverman B David

    2007-11-01

    . Conclusion With use of x-ray data from the protein data bank (PDB, these two metrics are shown to highlight, in a manner different from before, the structural changes that are induced in the overall domains as well as in the H3 loops of the complementarity-determining regions (CDR upon FAB antibody binding to a truncated and to a synthetic hemagglutinin viral antigenic target.

  2. [An anti-RNP antibody-positive case of aseptic meningitis induced by non-steroidal anti-inflammatory drugs in a young woman].

    Science.gov (United States)

    Matsui, Taro; Nakagawa, Keiichi; Yamazaki, Keishi; Wada, Taishi; Kadoya, Masato; Kaida, Kenichi

    2018-01-26

    A 19-year-old woman developed high fever, headache, and nausea after taking Loxoprofen for pharyngitis, followed by disturbed consciousness and nuchal stiffness. The patient and her mother had a history of Raynaud's phenomenon. Cerebrospinal fluid (CSF) examination indicated a diagnosis of aseptic meningitis and revealed high levels of Q albumin and IgG index. Anti-RNP antibodies were positive in serum and CSF. Her symptoms disappeared immediately after cessation of Loxoprofen and a drug lymphocyte stimulation test was negative, confirming a diagnosis of non-steroidal anti-inflammatory drugs (NSAIDs)-induced aseptic meningitis. It should be kept in mind that an immune abnormality such as serum and CSF anti-RNP antibodies may play a role in development of NSAIDs-induced aseptic meningitis. A history of usage of NSAIDs and a thorough examination of collagen diseases are useful for identification of the origin of aseptic meningitis in a young woman.

  3. Previous 60-Co radiation from Paratrygon aiereba mucus induces the production of highly responsive antibodies and a better immune response in mice

    International Nuclear Information System (INIS)

    Thomazi, Gabriela Ortega Coelho; Alves, Glaucie Jussilane; Turíbio, Thompson de Oliveira; Rocha, André Moreira; Aires, Raquel da Silva; Jácome, Larissa Barros Silvestre; Spencer, Patrick Jack

    2017-01-01

    Wounds from stinging freshwater stingrays are painful, difficult to heal and cause extensive necrosis and systemic phenomena. The treatment is symptomatic, of low efficiency and there is no therapy, which causes more suffering to the injured. This study aimed to evaluate the immune response induced by the native or irradiated by 60-Co gamma from Paratrygon aiereba mucus. IPEN’s Committee on Ethics in the Use of Animals (n.º126/2013) and lanes captured under license from the Chico Mendes Institute for Biodiversity Conservation (n.º6781-1/2014) approved this research. For the assays, sera from Swiss mice previously immunized against native or irradiated mucus were used. The proliferation of splenic B cells in response to mucus was evaluated by the In Vitro Induced Antibody Production method and serum and splenic cytokines were also quantified. Our data demonstrate that the irradiated mucus of P. aiereba induces greater production of antibodies and more immunological memory in the mice. Spleen cells from animals immunized against irradiated mucus produced IFN-γ, TNF-α and IL-10, and serum TNF-α (immunized group against irradiated mucus) and IL-6 and IL-17 (immunized group against native mucus). The results corroborate the use of ionizing radiation, with production of highly responsive antibodies and better immune response, besides proving that Paratrygon aiereba mucus is capable of stimulating cellular and humoral adaptive immune response, contributing to the continuity of associated investigations. (author)

  4. Previous 60-Co radiation from Paratrygon aiereba mucus induces the production of highly responsive antibodies and a better immune response in mice

    Energy Technology Data Exchange (ETDEWEB)

    Thomazi, Gabriela Ortega Coelho; Alves, Glaucie Jussilane; Turíbio, Thompson de Oliveira; Rocha, André Moreira; Aires, Raquel da Silva; Jácome, Larissa Barros Silvestre; Spencer, Patrick Jack, E-mail: gabiortegacoelho@usp.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil). Centro de Biotecnologia; Costa, Andrea da; Rodrigues, Jaqueline Pollizeli; Galisteo Júnior, Andrés Jimenez; Andrade Júnior, Heitor Franco de, E-mail: hfandrad@usp.br, E-mail: raquelaires@itpacporto.com.br [Universidade de São Paulo (USP), São Paulo, SP (Brazil). Laboratório de Protozoologia; Seibert, Carla Simone, E-mail: seibertcs@uft.edu.br [Universidade Federal do Tocantins (UFT), Porto Nacional, TO (Brazil)

    2017-07-01

    Wounds from stinging freshwater stingrays are painful, difficult to heal and cause extensive necrosis and systemic phenomena. The treatment is symptomatic, of low efficiency and there is no therapy, which causes more suffering to the injured. This study aimed to evaluate the immune response induced by the native or irradiated by 60-Co gamma from Paratrygon aiereba mucus. IPEN’s Committee on Ethics in the Use of Animals (n.º126/2013) and lanes captured under license from the Chico Mendes Institute for Biodiversity Conservation (n.º6781-1/2014) approved this research. For the assays, sera from Swiss mice previously immunized against native or irradiated mucus were used. The proliferation of splenic B cells in response to mucus was evaluated by the In Vitro Induced Antibody Production method and serum and splenic cytokines were also quantified. Our data demonstrate that the irradiated mucus of P. aiereba induces greater production of antibodies and more immunological memory in the mice. Spleen cells from animals immunized against irradiated mucus produced IFN-γ, TNF-α and IL-10, and serum TNF-α (immunized group against irradiated mucus) and IL-6 and IL-17 (immunized group against native mucus). The results corroborate the use of ionizing radiation, with production of highly responsive antibodies and better immune response, besides proving that Paratrygon aiereba mucus is capable of stimulating cellular and humoral adaptive immune response, contributing to the continuity of associated investigations. (author)

  5. Effects of the PPAR-β agonist GW501516 in an in vitro model of brain inflammation and antibody-induced demyelination

    Directory of Open Access Journals (Sweden)

    Honegger Paul

    2009-05-01

    Full Text Available Abstract Background Brain inflammation plays a central role in numerous brain pathologies, including multiple sclerosis (MS. Microglial cells and astrocytes are the effector cells of neuroinflammation. They can be activated also by agents such as interferon-γ (IFN-γ and lipopolysaccharide (LPS. Peroxisome proliferator-associated receptor (PPAR pathways are involved in the control of the inflammatory processes, and PPAR-β seems to play an important role in the regulation of central inflammation. In addition, PPAR-β agonists were shown to have trophic effects on oligodendrocytes in vitro, and to confer partial protection in experimental autoimmune encephalomyelitis (EAE, an animal model of MS. In the present work, a three-dimensional brain cell culture system was used as in vitro model to study antibody-induced demyelination and inflammatory responses. GW 501516, a specific PPAR-β agonist, was examined for its capacity to protect from antibody-mediated demyelination and to prevent inflammatory responses induced by IFN-γ and LPS. Methods Aggregating brain cells cultures were prepared from embryonal rat brain, and used to study the inflammatory responses triggered by IFN-γ and LPS and by antibody-mediated demyelination induced by antibodies directed against myelin-oligodendrocyte glycoprotein (MOG. The effects of GW 501516 on cellular responses were characterized by the quantification of the mRNA expression of tumor necrosis factor-α (TNF-α, interleukin-6 (IL-6, inducible NO synthase (i-NOS, PPAR-β, PPAR-γ, glial fibrillary acidic protein (GFAP, myelin basic protein (MBP, and high molecular weight neurofilament protein (NF-H. GFAP expression was also examined by immunocytochemistry, and microglial cells were visualized by isolectin B4 (IB4 and ED1 labeling. Results GW 501516 decreased the IFN-γ-induced up-regulation of TNF-α and iNOS in accord with the proposed anti-inflammatory effects of this PPAR-β agonist. However, it increased IL

  6. Oral immunotherapy induces IgG antibodies that act through FcγRIIb to suppress IgE-mediated hypersensitivity.

    Science.gov (United States)

    Burton, Oliver T; Logsdon, Stephanie L; Zhou, Joseph S; Medina-Tamayo, Jaciel; Abdel-Gadir, Azza; Noval Rivas, Magali; Koleoglou, Kyle J; Chatila, Talal A; Schneider, Lynda C; Rachid, Rima; Umetsu, Dale T; Oettgen, Hans C

    2014-12-01

    Food-induced anaphylaxis is triggered by specific IgE antibodies. Paradoxically, some subjects with significant IgE levels can ingest allergenic foods without incident. Similarly, subjects completing oral immunotherapy (OIT) tolerate food challenges despite persistent high-titer food-specific IgE. We sought to test whether IgG antibodies induced by food immunotherapy prevent food-induced anaphylaxis and whether this occurs through the inhibitory receptor FcγRIIb. Food allergy-susceptible Il4raF709 mice were enterally sensitized to ovalbumin (OVA). Similarly sensitized IgE-deficient (IgE(-/-)) Il4raF709 mice, which can ingest OVA without anaphylaxis, were subjected to a high-dose enteral OVA desensitization protocol (OIT). Sera from both groups were tested for the ability to activate or inhibit bone marrow mast cells (BMMCs) exposed to allergen or to passively transfer allergy to naive hosts. In parallel experiments sera obtained from patients with peanut allergy before and after undergoing OIT were interrogated for their ability to enhance or suppress peanut-induced activation in an indirect assay by using basophils from nonallergic donors. Il4raF709 mice exhibited strong OVA-specific IgE responses. Their sera efficiently sensitized BMMCs for activation by antigen challenge. Sera from Il4raF709/IgE(-/-) mice subjected to OVA OIT suppressed BMMC responses. This inhibition was IgG mediated and FcγRIIb dependent. Similarly, pre-OIT but not post-OIT sera from patients efficiently sensitized basophils for peanut-induced activation. IgG antibodies in post-OIT sera suppressed basophil activation by pre-OIT sera. This inhibition was blocked by antibodies against FcγRII. Food-specific IgG antibodies, such as those induced during OIT, inhibit IgE-mediated reactions. Strategies that favor IgG responses might prove useful in the management of food allergy. Copyright © 2014 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  7. Elicitation of neutralizing antibodies directed against CD4-induced epitope(s using a CD4 mimetic cross-linked to a HIV-1 envelope glycoprotein.

    Directory of Open Access Journals (Sweden)

    Antu K Dey

    Full Text Available The identification of HIV-1 envelope glycoprotein (Env structures that can generate broadly neutralizing antibodies (BNAbs is pivotal to the development of a successful vaccine against HIV-1 aimed at eliciting effective humoral immune responses. To that end, the production of novel Env structure(s that might induce BNAbs by presentation of conserved epitopes, which are otherwise occluded, is critical. Here, we focus on a structure that stabilizes Env in a conformation representative of its primary (CD4 receptor-bound state, thereby exposing highly conserved "CD4 induced" (CD4i epitope(s known to be important for co-receptor binding and subsequent virus infection. A CD4-mimetic miniprotein, miniCD4 (M64U1-SH, was produced and covalently complexed to recombinant, trimeric gp140 envelope glycoprotein (gp140 using site-specific disulfide linkages. The resulting gp140-miniCD4 (gp140-S-S-M64U1 complex was recognized by CD4i antibodies and the HIV-1 co-receptor, CCR5. The gp140-miniCD4 complex elicited the highest titers of CD4i binding antibodies as well as enhanced neutralizing antibodies against Tier 1 viruses as compared to gp140 protein alone following immunization of rabbits. Neutralization against HIV-2(7312/V434M and additional serum mapping confirm the specific elicitation of antibodies directed to the CD4i epitope(s. These results demonstrate the utility of structure-based approach in improving immunogenic response against specific region, such as the CD4i epitope(s here, and its potential role in vaccine application.

  8. Trypanosomiasis-induced B cell apoptosis results in loss of protective anti-parasite antibody responses and abolishment of vaccine-induced memory responses.

    Directory of Open Access Journals (Sweden)

    Magdalena Radwanska

    2008-05-01

    Full Text Available African trypanosomes of the Trypanosoma brucei species are extra-cellular parasites that cause human African trypanosomiasis (HAT as well as infections in game animals and livestock. Trypanosomes are known to evade the immune response of their mammalian host by continuous antigenic variation of their surface coat. Here, we aim to demonstrate that in addition, trypanosomes (i cause the loss of various B cell populations, (ii disable the hosts' capacity to raise a long-lasting specific protective anti-parasite antibody response, and (iii abrogate vaccine-induced protective response to a non-related human pathogen such as Bordetella pertussis. Using a mouse model for T. brucei, various B cell populations were analyzed by FACS at different time points of infection. The results show that during early onset of a T. brucei infection, spleen remodeling results in the rapid loss of the IgM(+ marginal zone (IgM(+MZ B cell population characterized as B220(+IgM(HighIgD(Int CD21(HighCD23(LowCD1d(+CD138(-. These cells, when isolated during the first peak of infection, stained positive for Annexin V and had increased caspase-3 enzyme activity. Elevated caspase-3 mRNA levels coincided with decreased mRNA levels of the anti-apoptotic Bcl-2 protein and BAFF receptor (BAFF-R, indicating the onset of apoptosis. Moreover, affected B cells became unresponsive to stimulation by BCR cross-linking with anti-IgM Fab fragments. In vivo, infection-induced loss of IgM(+ B cells coincided with the disappearance of protective variant-specific T-independent IgM responses, rendering the host rapidly susceptible to re-challenge with previously encountered parasites. Finally, using the well-established human diphtheria, tetanus, and B. pertussis (DTPa vaccination model in mice, we show that T. brucei infections abrogate vaccine-induced protective responses to a non-related pathogen such as B. pertussis. Infections with T. brucei parasites result in the rapid loss of T

  9. Trypanosomiasis-induced B cell apoptosis results in loss of protective anti-parasite antibody responses and abolishment of vaccine-induced memory responses.

    Science.gov (United States)

    Radwanska, Magdalena; Guirnalda, Patrick; De Trez, Carl; Ryffel, Bernard; Black, Samuel; Magez, Stefan

    2008-05-30

    African trypanosomes of the Trypanosoma brucei species are extra-cellular parasites that cause human African trypanosomiasis (HAT) as well as infections in game animals and livestock. Trypanosomes are known to evade the immune response of their mammalian host by continuous antigenic variation of their surface coat. Here, we aim to demonstrate that in addition, trypanosomes (i) cause the loss of various B cell populations, (ii) disable the hosts' capacity to raise a long-lasting specific protective anti-parasite antibody response, and (iii) abrogate vaccine-induced protective response to a non-related human pathogen such as Bordetella pertussis. Using a mouse model for T. brucei, various B cell populations were analyzed by FACS at different time points of infection. The results show that during early onset of a T. brucei infection, spleen remodeling results in the rapid loss of the IgM(+) marginal zone (IgM(+)MZ) B cell population characterized as B220(+)IgM(High)IgD(Int) CD21(High)CD23(Low)CD1d(+)CD138(-). These cells, when isolated during the first peak of infection, stained positive for Annexin V and had increased caspase-3 enzyme activity. Elevated caspase-3 mRNA levels coincided with decreased mRNA levels of the anti-apoptotic Bcl-2 protein and BAFF receptor (BAFF-R), indicating the onset of apoptosis. Moreover, affected B cells became unresponsive to stimulation by BCR cross-linking with anti-IgM Fab fragments. In vivo, infection-induced loss of IgM(+) B cells coincided with the disappearance of protective variant-specific T-independent IgM responses, rendering the host rapidly susceptible to re-challenge with previously encountered parasites. Finally, using the well-established human diphtheria, tetanus, and B. pertussis (DTPa) vaccination model in mice, we show that T. brucei infections abrogate vaccine-induced protective responses to a non-related pathogen such as B. pertussis. Infections with T. brucei parasites result in the rapid loss of T

  10. Trypanosomiasis-Induced B Cell Apoptosis Results in Loss of Protective Anti-Parasite Antibody Responses and Abolishment of Vaccine-Induced Memory Responses

    Science.gov (United States)

    Radwanska, Magdalena; Guirnalda, Patrick; De Trez, Carl; Ryffel, Bernard; Black, Samuel; Magez, Stefan

    2008-01-01

    African trypanosomes of the Trypanosoma brucei species are extra-cellular parasites that cause human African trypanosomiasis (HAT) as well as infections in game animals and livestock. Trypanosomes are known to evade the immune response of their mammalian host by continuous antigenic variation of their surface coat. Here, we aim to demonstrate that in addition, trypanosomes (i) cause the loss of various B cell populations, (ii) disable the hosts' capacity to raise a long-lasting specific protective anti-parasite antibody response, and (iii) abrogate vaccine-induced protective response to a non-related human pathogen such as Bordetella pertussis. Using a mouse model for T. brucei, various B cell populations were analyzed by FACS at different time points of infection. The results show that during early onset of a T. brucei infection, spleen remodeling results in the rapid loss of the IgM+ marginal zone (IgM+MZ) B cell population characterized as B220+IgMHighIgDInt CD21HighCD23LowCD1d+CD138−. These cells, when isolated during the first peak of infection, stained positive for Annexin V and had increased caspase-3 enzyme activity. Elevated caspase-3 mRNA levels coincided with decreased mRNA levels of the anti-apoptotic Bcl-2 protein and BAFF receptor (BAFF-R), indicating the onset of apoptosis. Moreover, affected B cells became unresponsive to stimulation by BCR cross-linking with anti-IgM Fab fragments. In vivo, infection-induced loss of IgM+ B cells coincided with the disappearance of protective variant-specific T-independent IgM responses, rendering the host rapidly susceptible to re-challenge with previously encountered parasites. Finally, using the well-established human diphtheria, tetanus, and B. pertussis (DTPa) vaccination model in mice, we show that T. brucei infections abrogate vaccine-induced protective responses to a non-related pathogen such as B. pertussis. Infections with T. brucei parasites result in the rapid loss of T–cell independent IgM+MZ B

  11. A mimotope peptide of Aβ42 fibril-specific antibodies with Aβ42 fibrillation inhibitory activity induces anti-Aβ42 conformer antibody response by a displayed form on an M13 phage in mice.

    Science.gov (United States)

    Tanaka, Koichi; Nishimura, Masaaki; Yamaguchi, Yuya; Hashiguchi, Shuhei; Takiguchi, Sho; Yamaguchi, Makoto; Tahara, Haruna; Gotanda, Takuma; Abe, Risa; Ito, Yuji; Sugimura, Kazuhisa

    2011-07-01

    In Alzheimer's disease (AD), amyloid-β (Aβ) peptides accumulate in the brain in different forms, including fibrils and oligomers. Recently, we established three distinct conformation-dependent human single-chain Fv (scFv) antibodies, including B6 scFv, which bound to Aβ42 fibril but not to soluble-form Aβ, inhibiting Aβ42 fibril formation. In this study, we determined the mimotopes of these antibodies and found a common mimotope sequence, B6-C15, using the Ph.D.-C7C phage library. The B6-C15 showed weak homology to the C-terminus of Aβ42 containing GXXXG dimerization motifs. We synthesized the peptide of B6-C15 fused with biotinylated TAT at the N-terminus (TAT-B6-C15) and characterized its biochemical features on an Aβ42-fibrillation reaction in vitro. We demonstrated that, first, TAT-B6-C15 inhibited Aβ42 fibril formation; secondly, TAT-B6-C15 bound to prefibril Aβ42 oligomers but not to monomers, trimers, tetramers, fibrils, or ultrasonicated fragments; thirdly, TAT-B6-C15 inhibited Aβ42-induced cytotoxicity against human SH-SY5Y neuroblastoma cells; and, fourthly, when mice were administered B6-C15-phages dissolved in phosphate-buffered saline, the anti-Aβ42 conformer IgG antibody response was induced. These results suggested that the B6-C15 peptide might provide unique opportunities to analyze the Aβ42 fibrillation pathway and develop a vaccine vehicle for Alzheimer's disease. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Systemic administration of an anti-tumor necrosis factor-alpha monoclonal antibody protects against endotoxin-induced uveitis in rats

    OpenAIRE

    Ge, Qingman; Wang, Shaocheng; Zheng, Yuezhong

    2016-01-01

    Objective: This study was to evaluate the effect of systemic injection of an anti-tumor necrosis factor alpha (TNF-?) monoclonal antibody (mAb) on endotoxin-induced uveitis (EIU). Materials and Methods: Fifty-six male Wistar rats (6?8 weeks old) were randomly divided into three groups: EIU, anti-TNF-? mAb + EIU, and control. EIU was induced by injecting Escherichia coli O55:B5 lipopolysaccharide (LPS) into the hind footpad of the rats (150 ?g/rat). The anti-TNF-? mAb (1 ?g/kg) was administrat...

  13. Curcumin induced nanoscale CD44 molecular redistribution and antigen-antibody interaction on HepG2 cell surface

    Energy Technology Data Exchange (ETDEWEB)

    Wang Mu [Department of Chemistry, Jinan University, 601 Huangpu Road West, Tianhe District, Guangzhou 510632 (China); Ruan Yuxia [Department of Ophthalmology, The First Affiliated Hospital, Jinan University, 601 Huangpu Road West, Tianhe District, Guangzhou 510632 (China); Xing Xiaobo; Chen Qian; Peng, Yuan [Department of Chemistry, Jinan University, 601 Huangpu Road West, Tianhe District, Guangzhou 510632 (China); Cai Jiye, E-mail: tjycai@jnu.edu.cn [Department of Chemistry, Jinan University, 601 Huangpu Road West, Tianhe District, Guangzhou 510632 (China)

    2011-07-04

    Graphical abstract: Highlights: > In this study, we investigate the changes of CD44 expression and distribution on HepG2 cells after curcumin treatment. > We find curcumin is able to change the morphology and ultrastructure of HepG2 cells. > Curcumin can reduce the expression of CD44 molecules and induce the nanoscale molecular redistribution on cell surface. > The binding force between CD44-modified AFM tip and the HepG2 cell surface decreases after curcumin-treatment. - Abstract: The cell surface glycoprotein CD44 was implicated in the progression, metastasis and apoptosis of certain human tumors. In this study, we used atomic force microscope (AFM) to monitor the effect of curcumin on human hepatocellular carcinoma (HepG2) cell surface nanoscale structure. High-resolution imaging revealed that cell morphology and ultrastructure changed a lot after being treated with curcumin. The membrane average roughness increased (10.88 {+-} 4.62 nm to 129.70 {+-} 43.72 nm) and the expression of CD44 decreased (99.79 {+-} 0.16% to 75.14 {+-} 8.37%). Laser scanning confocal microscope (LSCM) imaging showed that CD44 molecules were located on the cell membrane. The florescence intensity in control group was weaker than that in curcumin treated cells. Most of the binding forces between CD44 antibodies and untreated HepG2 cell membrane were around 120-220 pN. After being incubated with curcumin, the major forces focused on 70-150 pN (10 {mu}M curcumin-treated) and 50-120 pN (20 {mu}M curcumin-treated). These results suggested that, as result of nanoscale molecular redistribution, changes of the cell surface were in response to external treatment of curcumin. The combination of AFM and LSCM could be a powerful method to detect the distribution of cell surface molecules and interactions between molecules and their ligands.

  14. Inhibition of Megakaryocyte Differentiation by Antibody-Drug Conjugates (ADCs) is Mediated by Macropinocytosis: Implications for ADC-induced Thrombocytopenia.

    Science.gov (United States)

    Zhao, Hui; Gulesserian, Sara; Ganesan, Sathish Kumar; Ou, Jimmy; Morrison, Karen; Zeng, Zhilan; Robles, Veronica; Snyder, Josh; Do, Lisa; Aviña, Hector; Karki, Sher; Stover, David R; Doñate, Fernando

    2017-09-01

    Thrombocytopenia is a common adverse event in cancer patients treated with antibody-drug conjugates (ADC), including AGS-16C3F, an ADC targeting ENPP3 (ectonucleotide pyrophosphatase/phosphodiesterase-3) and trastuzumab emtansine (T-DM1). This study aims to elucidate the mechanism of action of ADC-induced thrombocytopenia. ENPP3 expression in platelets and megakaryocytes (MK) was investigated and shown to be negative. The direct effect of AGS-16C3F on platelets was evaluated using platelet rich plasma following the expression of platelet activation markers. Effects of AGS-16C3F, T-DM1, and control ADCs on maturing megakaryocytes were evaluated in an in vitro system in which human hematopoietic stem cells (HSC) were differentiated into MKs. AGS-16C3F, like T-DM1, did not affect platelets directly, but inhibited MK differentiation by the activity of Cys-mcMMAF, its active metabolite. FcγRIIA did not appear to play an important role in ADC cytotoxicity to differentiating MKs. AGS-16C3F, cytotoxic to MKs, did not bind to FcγRIIA on MKs. Blocking the interaction of T-DM1 with FcγRIIA did not prevent the inhibition of MK differentiation and IgG1-mcMMAF was not as cytotoxic to MKs despite binding to FcγRIIA. Several lines of evidence suggest that internalization of AGS-16C3F into MKs is mediated by macropinocytosis. Macropinocytosis activity of differentiating HSCs correlated with cell sensitivity to AGS-16C3F. AGS-16C3F was colocalized with a macropinocytosis marker, dextran-Texas Red in differentiating MKs. Ethyl isopropyl amiloride (EIPA), a macropinocytosis inhibitor, blocked internalization of dextran-Texas Red and AGS-16C3F. These data support the notion that inhibition of MK differentiation via macropinocytosis-mediated internalization plays a role in ADC-induced thrombocytopenia. Mol Cancer Ther; 16(9); 1877-86. ©2017 AACR See related article by Zhao et al., p. 1866 . ©2017 American Association for Cancer Research.

  15. Development of an ErbB4 monoclonal antibody that blocks neuregulin-1-induced ErbB4 activation in cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Okazaki, Shogo [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Nakatani, Fumi [Cell Biology Laboratory, Department of Pharmaceutical Sciences, Faculty of Pharmacy, Kinki University, Higashiosaka, Osaka 577-8502 Japan (Japan); Masuko, Kazue; Tsuchihashi, Kenji [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Ueda, Shiho; Masuko, Takashi [Cell Biology Laboratory, Department of Pharmaceutical Sciences, Faculty of Pharmacy, Kinki University, Higashiosaka, Osaka 577-8502 Japan (Japan); Saya, Hideyuki [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Nagano, Osamu, E-mail: osmna@sb3.so-net.ne.jp [Division of Gene Regulation, Institute for Advanced Medical Research, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan)

    2016-01-29

    The use of monoclonal antibodies (mAbs) for cancer therapy is one of the most important strategies for current cancer treatment. The epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases, which regulates cancer cell proliferation, survival, and migration, is a major molecular target for antibody-based therapy. ErbB4/HER4, which contains a ligand-binding extracellular region, is activated by several ligands, including neuregulins (NRGs), heparin-binding EGF-like growth factor, betacellulin and epiregulin. Although there are clinically approved antibodies for ErbB1 and ErbB2, there are no available therapeutic mAbs for ErbB4, and it is not known whether ErbB4 is a useful target for antibody-based cancer therapy. In this study, we developed an anti-ErbB4 mAb (clone P6-1) that suppresses NRG-dependent activation of ErbB4 and examined its effect on breast cancer cell proliferation in the extracellular matrix. - Highlights: • We newly generated four clones of human ErbB4 specific mAb. • ErbB4 mAb clone P6-1 blocks ErbB4 phosphorylation induced by NRG-1. • ErbB4 mAb clone P6-1 suppresses NRG-1-promoted breast cancer cells proliferation on three dimensional culture condition.

  16. Subversion of early innate antiviral responses during antibody-dependent enhancement of Dengue virus infection induces severe disease in immunocompetent mice.

    Science.gov (United States)

    Costa, Vivian V; Fagundes, Caio T; Valadão, Deborah F; Ávila, Thiago V; Cisalpino, Daniel; Rocha, Rebeca F; Ribeiro, Lucas S; Ascenção, Fernando R; Kangussu, Lucas M; Celso, M Q; Astigarraga, Ruiz G; Gouveia, Frederico L; Silva, Tarcília A; Bonaventura, Daniela; Sampaio, Divaldo de Almeida; Leite, Ana Cristina L; Teixeira, Mauro M; Souza, Danielle G

    2014-08-01

    Dengue is a mosquito-borne disease caused by one of four serotypes of Dengue virus (DENV-1-4). Epidemiologic and observational studies demonstrate that the majority of severe dengue cases, dengue hemorrhagic fever and dengue shock syndrome (DHF/DSS), occurs predominantly in either individuals with cross-reactive immunity following a secondary heterologous infection or in infants with primary DENV infections born from dengue-immune mothers, suggesting that B-cell-mediated and antibody responses impact on disease evolution. We demonstrate here that B cells play a pivotal role in host responses against primary DENV infection in mice. After infection, μMT(-/-) mice showed increased viral loads followed by severe disease manifestation characterized by intense thrombocytopenia, hemoconcentration, cytokine production and massive liver damage that culminated in death. In addition, we show that poly and monoclonal anti-DENV-specific antibodies can sufficiently increase viral replication through a suppression of early innate antiviral responses and enhance disease manifestation, so that a mostly non-lethal illness becomes a fatal disease resembling human DHF/DSS. Finally, treatment with intravenous immunoglobulin containing anti-DENV antibodies confirmed the potential enhancing capacity of subneutralizing antibodies to mediate virus infection and replication and induce severe disease manifestation of DENV-infected mice. Thus, our results show that humoral responses unleashed during DENV infections can exert protective or pathological outcomes and provide insight into the pathogenesis of this important human pathogen.

  17. Development of a vaccine to mitigate greenhouse gas emissions in agriculture: vaccination of sheep with methanogen fractions induces antibodies that block methane production in vitro.

    Science.gov (United States)

    Wedlock, D N; Pedersen, G; Denis, M; Dey, D; Janssen, P H; Buddle, B M

    2010-02-01

    To develop an understanding of the immune responses of ruminants to methanogens, and to provide proof of a concept that harnessing the immune system of ruminants is a potentially viable approach to mitigate greenhouse gas emissions from agriculture. Four subcellular fractions, namely cytoplasmic, two cell-wall preparations, and cell wall-derived proteins were prepared from Methanobrevibacter ruminantium M1. Twenty sheep (10 months of age) were vaccinated with these fractions or with whole cells (n=4 per group). Sheep were re-vaccinated once after 3 weeks, and antibody responses to M. ruminantium M1 antigens in sera and saliva measured using ELISA at 2 weeks after the second vaccination. Antigens recognised by the antisera were visualised using Western blotting. The antisera were tested in vitro for their impact on M. ruminantium M1, measuring the effect on cell growth, methane production, and ability to induce agglutination. Basal levels (pre-vaccination) of antibodies against M. ruminantium M1 antigens were low. Vaccination with the antigenic fractions induced strong antibody responses in serum. Both IgG and IgA responses to methanogen antigens were detected in saliva following vaccination. Western blot analysis of the antisera indicated reactivity of antibodies, and a wide range of proteins was present in the different methanogen fractions. Antisera against the various fractions agglutinated methanogens in an in-vitro assay. In addition, these antisera decreased the growth of a pure culture of a methanogen and production of methane in vitro. Antigens from methanogens are immunogenic in ruminants, and antisera from sheep vaccinated with fractions of methanogens have a significant impact on these organisms, inducing cell agglutination, and decreasing growth of methanogens and production of methane. Only antisera to selected methanogen fractions were able to achieve these effects. The results demonstrate the feasibility of a vaccination strategy to mitigate emission

  18. Antibodies against glycolipids enhance antifungal activity of macrophages and reduce fungal burden after infection with Paracoccidioides brasiliensis

    Directory of Open Access Journals (Sweden)

    Renata Amelia eBueno

    2016-02-01

    Full Text Available Paracoccidioidomycosis is a fungal disease endemic in Latin America. Polyclonal antibodies to acidic glycosphingolipids (GSLs from Paracoccidioides brasiliensis opsonized yeast forms in vitro increasing phagocytosis and reduced the fungal burden of infected animals. Antibodies to GSL were active in both prophylactic and therapeutic protocols using a murine intratracheal infection model. Pathological examination of the lungs of animals treated with antibodies to GSL showed well-organized granulomas and minimally damaged parenchyma compared to the untreated control. Murine peritoneal macrophages activated by IFN-γ and incubated with antibodies against acidic GSLs more effectively phagocytosed and killed P. brasiliensis yeast cells as well as produced more nitric oxide compared to controls. The present work discloses a novel target of protective antibodies against P. brasiliensis adding to other well-studied mediators of the immune response to this fungus.

  19. Exposure to the Epstein–Barr Viral Antigen Latent Membrane Protein 1 Induces Myelin-Reactive Antibodies In Vivo

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    Yakov Lomakin

    2017-07-01

    Full Text Available Multiple sclerosis (MS is an autoimmune chronic inflammatory disease of the central nervous system (CNS. Cross-reactivity of neuronal proteins with exogenous antigens is considered one of the possible mechanisms of MS triggering. Previously, we showed that monoclonal myelin basic protein (MBP-specific antibodies from MS patients cross-react with Epstein–Barr virus (EBV latent membrane protein 1 (LMP1. In this study, we report that exposure of mice to LMP1 results in induction of myelin-reactive autoantibodies in vivo. We posit that chronic exposure or multiple acute exposures to viral antigen may redirect B cells from production of antiviral antibodies to antibodies, specific to myelin antigen. However, even in inbred animals, which are almost identical in terms of their genomes, such an effect is only observed in 20–50% of animals, indicating that this change occurs by chance, rather than systematically. Cross-immunoprecipitation analysis showed that only part of anti-MBP antibodies from LMP1-immunized mice might simultaneously bind LMP1. In contrast, the majority of anti-LMP1 antibodies from MBP-immunized mice bind MBP. De novo sequencing of anti-LMP1 and anti-MBP antibodies by mass spectrometry demonstrated enhanced clonal diversity in LMP1-immunized mice in comparison with MBP-immunized mice. We suggest that induction of MBP-reactive antibodies in LMP1-immunized mice may be caused by either Follicular dendritic cells (FDCs or by T cells that are primed by myelin antigens directly in CNS. Our findings help to elucidate the still enigmatic link between EBV infection and MS development, suggesting that myelin-reactive antibodies raised as a response toward EBV protein LMP1 are not truly cross-reactive but are primarily caused by epitope spreading.

  20. Exposure to the Epstein–Barr Viral Antigen Latent Membrane Protein 1 Induces Myelin-Reactive Antibodies In Vivo

    Science.gov (United States)

    Lomakin, Yakov; Arapidi, Georgii Pavlovich; Chernov, Alexander; Ziganshin, Rustam; Tcyganov, Evgenii; Lyadova, Irina; Butenko, Ivan Olegovich; Osetrova, Maria; Ponomarenko, Natalia; Telegin, Georgy; Govorun, Vadim Markovich; Gabibov, Alexander; Belogurov, Alexey

    2017-01-01

    Multiple sclerosis (MS) is an autoimmune chronic inflammatory disease of the central nervous system (CNS). Cross-reactivity of neuronal proteins with exogenous antigens is considered one of the possible mechanisms of MS triggering. Previously, we showed that monoclonal myelin basic protein (MBP)-specific antibodies from MS patients cross-react with Epstein–Barr virus (EBV) latent membrane protein 1 (LMP1). In this study, we report that exposure of mice to LMP1 results in induction of myelin-reactive autoantibodies in vivo. We posit that chronic exposure or multiple acute exposures to viral antigen may redirect B cells from production of antiviral antibodies to antibodies, specific to myelin antigen. However, even in inbred animals, which are almost identical in terms of their genomes, such an effect is only observed in 20–50% of animals, indicating that this change occurs by chance, rather than systematically. Cross-immunoprecipitation analysis showed that only part of anti-MBP antibodies from LMP1-immunized mice might simultaneously bind LMP1. In contrast, the majority of anti-LMP1 antibodies from MBP-immunized mice bind MBP. De novo sequencing of anti-LMP1 and anti-MBP antibodies by mass spectrometry demonstrated enhanced clonal diversity in LMP1-immunized mice in comparison with MBP-immunized mice. We suggest that induction of MBP-reactive antibodies in LMP1-immunized mice may be caused by either Follicular dendritic cells (FDCs) or by T cells that are primed by myelin antigens directly in CNS. Our findings help to elucidate the still enigmatic link between EBV infection and MS development, suggesting that myelin-reactive antibodies raised as a response toward EBV protein LMP1 are not truly cross-reactive but are primarily caused by epitope spreading. PMID:28729867

  1. Exposure to the Epstein-Barr Viral Antigen Latent Membrane Protein 1 Induces Myelin-Reactive Antibodies In Vivo.

    Science.gov (United States)

    Lomakin, Yakov; Arapidi, Georgii Pavlovich; Chernov, Alexander; Ziganshin, Rustam; Tcyganov, Evgenii; Lyadova, Irina; Butenko, Ivan Olegovich; Osetrova, Maria; Ponomarenko, Natalia; Telegin, Georgy; Govorun, Vadim Markovich; Gabibov, Alexander; Belogurov, Alexey

    2017-01-01

    Multiple sclerosis (MS) is an autoimmune chronic inflammatory disease of the central nervous system (CNS). Cross-reactivity of neuronal proteins with exogenous antigens is considered one of the possible mechanisms of MS triggering. Previously, we showed that monoclonal myelin basic protein (MBP)-specific antibodies from MS patients cross-react with Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1). In this study, we report that exposure of mice to LMP1 results in induction of myelin-reactive autoantibodies in vivo . We posit that chronic exposure or multiple acute exposures to viral antigen may redirect B cells from production of antiviral antibodies to antibodies, specific to myelin antigen. However, even in inbred animals, which are almost identical in terms of their genomes, such an effect is only observed in 20-50% of animals, indicating that this change occurs by chance, rather than systematically. Cross-immunoprecipitation analysis showed that only part of anti-MBP antibodies from LMP1-immunized mice might simultaneously bind LMP1. In contrast, the majority of anti-LMP1 antibodies from MBP-immunized mice bind MBP. De novo sequencing of anti-LMP1 and anti-MBP antibodies by mass spectrometry demonstrated enhanced clonal diversity in LMP1-immunized mice in comparison with MBP-immunized mice. We suggest that induction of MBP-reactive antibodies in LMP1-immunized mice may be caused by either Follicular dendritic cells (FDCs) or by T cells that are primed by myelin antigens directly in CNS. Our findings help to elucidate the still enigmatic link between EBV infection and MS development, suggesting that myelin-reactive antibodies raised as a response toward EBV protein LMP1 are not truly cross-reactive but are primarily caused by epitope spreading.

  2. Monoclonal antibody against brain calmodulin-dependent protein kinase type II detects putative conformational changes induced by Ca2+-calmodulin

    International Nuclear Information System (INIS)

    LeVine, H. III; Su, J.L.; Sahyoun, N.E.

    1988-01-01

    A mouse monoclonal IgG1 antibody has been generated against the soluble form of the calmodulin-dependent protein kinase type II. This antibody recognizes both the soluble and cytoskeletal forms of the enzyme, requiring Ca 2+ for the interaction. Other divalent cations such as Zn 2+ , Mn 2+ , Cd 2+ , Co 2+ , and Ni 2+ will substitute for Ca 2+ , while Mg 2+ and Ba 2+ will not. The antibody reacts with both the α- and β-subunits on Western blots in a similar Ca 2+ -dependent fashion but with a lower sensitivity. The affinity of the antibody for the kinase is 0.13 nM determined by displacement of 125 I Bolton-Hunter-labeled kinase with unlabeled enzyme. Calmodulin and antibody reciprocally potentiate each other's interaction with the enzyme. This is illustrated both by direct binding studies and by a decrease of the K/sub m app/ for calmodulin and an increase in the V/sub max/ for the autophosphorylation reaction of the enzyme. The antibody thus appears to recognize and stabilize a conformation of the kinase which favors calmodulin binding although it does not itself activate the kinase in the absence of calmodulin. Since the M/sub r/ 30,000 catalytic fragment of the kinase is not immunoreactive, either the antibody combining site of the kinase must be present in the noncatalytic portion of the protein along with the calmodulin binding site or proteolysis interferes with the putative Ca 2+ -dependent conformational change. Thus, monoclonal antibodies can be useful tools in elucidating the mechanism by which Ca 2+ and calmodulin act on the kinase molecule

  3. Multimeric scaffolds displaying the HIV-1 envelope MPER induce MPER-specific antibodies and cross-neutralizing antibodies when co-immunized with gp160 DNA.

    Science.gov (United States)

    Krebs, Shelly J; McBurney, Sean P; Kovarik, Dina N; Waddell, Chelsea D; Jaworski, J Pablo; Sutton, William F; Gomes, Michelle M; Trovato, Maria; Waagmeester, Garret; Barnett, Susan J; DeBerardinis, Piergiuseppe; Haigwood, Nancy L

    2014-01-01

    Developing a vaccine that overcomes the diversity of HIV-1 is likely to require a strategy that directs antibody (Ab) responses toward conserved regions of the viral Envelope (Env). However, the generation of neutralizing Abs (NAbs) targeting these regions through vaccination has proven to be difficult. One conserved region of particular interest is the membrane proximal external region (MPER) of Env located within the gp41 ectodomain. In order to direct the immune response to this region, the MPER and gp41 ectodomain were expressed separately as N-terminal fusions to the E2 protein of Geobacillus stearothermophilus. The E2 protein acts as a scaffold by self-assembling into 60-mer particles, displaying up to 60 copies of the fused target on the surface. Rabbits were immunized with E2 particles displaying MPER and/or the gp41 ectodomain in conjunction with DNA encoding full-length gp160. Only vaccines including E2 particles displaying MPER elicited MPER-specific Ab responses. NAbs were elicited after two immunizations that largely targeted the V3 loop. To overcome V3 immunodominance in the DNA component, E2 particles displaying MPER were used in conjunction with gp160 DNA lacking hypervariable regions V2, V3, or combined V1V2V3. All rabbits had HIV binding Ab responses and NAbs following the second vaccination. Using HIV-2/HIV-1 MPER chimeric viruses as targets, NAbs were detected in 12/16 rabbits after three immunizations. Low levels of NAbs specific for Tier 1 and 2 viruses were observed in all groups. This study provides evidence that co-immunizing E2 particles displaying MPER and gp160 DNA can focus Ab responses toward conserved regions of Env.

  4. Multimeric scaffolds displaying the HIV-1 envelope MPER induce MPER-specific antibodies and cross-neutralizing antibodies when co-immunized with gp160 DNA.

    Directory of Open Access Journals (Sweden)

    Shelly J Krebs

    Full Text Available Developing a vaccine that overcomes the diversity of HIV-1 is likely to require a strategy that directs antibody (Ab responses toward conserved regions of the viral Envelope (Env. However, the generation of neutralizing Abs (NAbs targeting these regions through vaccination has proven to be difficult. One conserved region of particular interest is the membrane proximal external region (MPER of Env located within the gp41 ectodomain. In order to direct the immune response to this region, the MPER and gp41 ectodomain were expressed separately as N-terminal fusions to the E2 protein of Geobacillus stearothermophilus. The E2 protein acts as a scaffold by self-assembling into 60-mer particles, displaying up to 60 copies of the fused target on the surface. Rabbits were immunized with E2 particles displaying MPER and/or the gp41 ectodomain in conjunction with DNA encoding full-length gp160. Only vaccines including E2 particles displaying MPER elicited MPER-specific Ab responses. NAbs were elicited after two immunizations that largely targeted the V3 loop. To overcome V3 immunodominance in the DNA component, E2 particles displaying MPER were used in conjunction with gp160 DNA lacking hypervariable regions V2, V3, or combined V1V2V3. All rabbits had HIV binding Ab responses and NAbs following the second vaccination. Using HIV-2/HIV-1 MPER chimeric viruses as targets, NAbs were detected in 12/16 rabbits after three immunizations. Low levels of NAbs specific for Tier 1 and 2 viruses were observed in all groups. This study provides evidence that co-immunizing E2 particles displaying MPER and gp160 DNA can focus Ab responses toward conserved regions of Env.

  5. Receptor-binding domain of SARS-CoV spike protein induces highly potent neutralizing antibodies: implication for developing subunit vaccine

    International Nuclear Information System (INIS)

    He Yuxian; Zhou Yusen; Liu Shuwen; Kou Zhihua; Li Wenhui; Farzan, Michael; Jiang Shibo

    2004-01-01

    The spike (S) protein of severe acute respiratory syndrome (SARS) coronavirus (CoV), a type I transmembrane envelope glycoprotein, consists of S1 and S2 domains responsible for virus binding and fusion, respectively. The S1 contains a receptor-binding domain (RBD) that can specifically bind to angiotensin-converting enzyme 2 (ACE2), the receptor on target cells. Here we show that a recombinant fusion protein (designated RBD-Fc) containing 193-amino acid RBD (residues 318-510) and a human IgG1 Fc fragment can induce highly potent antibody responses in the immunized rabbits. The antibodies recognized RBD on S1 domain and completely inhibited SARS-CoV infection at a serum dilution of 1:10,240. Rabbit antisera effectively blocked binding of S1, which contains RBD, to ACE2. This suggests that RBD can induce highly potent neutralizing antibody responses and has potential to be developed as an effective and safe subunit vaccine for prevention of SARS

  6. A small antigenic determinant of the Chikungunya virus E2 protein is sufficient to induce neutralizing antibodies which are partially protective in mice.

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    Christopher Weber

    2015-04-01

    Full Text Available The mosquito-borne Chikungunya virus (CHIKV causes high fever and severe joint pain in humans. It is expected to spread in the future to Europe and has recently reached the USA due to globalization, climate change and vector switch. Despite this, little is known about the virus life cycle and, so far, there is no specific treatment or vaccination against Chikungunya infections. We aimed here to identify small antigenic determinants of the CHIKV E2 protein able to induce neutralizing immune responses.E2 enables attachment of the virus to target cells and a humoral immune response against E2 should protect from CHIKV infections. Seven recombinant proteins derived from E2 and consisting of linear and/or structural antigens were created, and were expressed in and purified from E. coli. BALB/c mice were vaccinated with these recombinant proteins and the mouse sera were screened for neutralizing antibodies. Whereas a linear N-terminally exposed peptide (L and surface-exposed parts of the E2 domain A (sA alone did not induce neutralizing antibodies, a construct containing domain B and a part of the β-ribbon (called B+ was sufficient to induce neutralizing antibodies. Furthermore, domain sA fused to B+ (sAB+ induced the highest amount of neutralizing antibodies. Therefore, the construct sAB+ was used to generate a recombinant modified vaccinia virus Ankara (MVA, MVA-CHIKV-sAB+. Mice were vaccinated with MVA-CHIKV-sAB+ and/or the recombinant protein sAB+ and were subsequently challenged with wild-type CHIKV. Whereas four vaccinations with MVA-CHIKV-sAB+ were not sufficient to protect mice from a CHIKV infection, protein vaccination with sAB+ markedly reduced the viral titers of vaccinated mice.The recombinant protein sAB+ contains important structural antigens for a neutralizing antibody response in mice and its formulation with appropriate adjuvants might lead to a future CHIKV vaccine.

  7. Liver-X-receptor activator prevents homocysteine-induced production of IgG antibodies from murine B lymphocytes via the ROS-NF-κB pathway

    International Nuclear Information System (INIS)

    Chang Lina; Zhang, Zhenmin; Li Wenjing; Dai Jing; Guan Youfei; Wang Xian

    2007-01-01

    Our previous study showed that homosysteine (Hcy) promotes proliferation of mouse splenic B lymphocytes. In this study, we investigated whether Hcy could stimulate the production of IgG antibodies. Hcy significantly increased the production of IgG antibodies from resting B lymphocytes. B lymphocytes from ApoE-knockout mice with hyperhomocysteinemia showed elevated IgG secretion at either the basal Hcy level or in response to lipopolysaccharide. Hcy promoted reactive oxygen species (ROS) formation, and free radical scavengers, MnTMPyP decreased Hcy-induced IgG secretion. The inhibitor of NF-κB (MG132) also significantly reduced Hcy-induced IgG secretion. Furthermore, Hcy-induced formation of ROS, activation of NF-κB, and secretion of IgG could be inhibited by the liver-X-receptor (LXR) agonist TO 901317. Thus, our data provide strong evidence that HHcy induces IgG production from murine splenic B lymphocytes both in vitro and in vivo. The mechanism might be through the ROS-NF-κB pathway and can be attenuated by the activation of LXR

  8. Quadrivalent Human Papillomavirus (HPV) Vaccine Induces HPV-Specific Antibodies in the Oral Cavity: Results From the Mid-Adult Male Vaccine Trial.

    Science.gov (United States)

    Pinto, Ligia A; Kemp, Troy J; Torres, B Nelson; Isaacs-Soriano, Kimberly; Ingles, Donna; Abrahamsen, Martha; Pan, Yuanji; Lazcano-Ponce, Eduardo; Salmeron, Jorge; Giuliano, Anna R

    2016-10-15

    Human papillomavirus virus type 16 (HPV-16) and HPV-18 cause a large proportion of oropharyngeal cancers, which are increasing in incidence among males, and vaccine efficacy against oral HPV infections in men has not been previously evaluated. Sera and saliva collected in mouthwash and Merocel sponges at day 1 and month 7 were obtained from 150 men aged 27-45 years from Tampa, Florida, and Cuernavaca, Mexico, who received Gardasil at day 1 and months 2 and 6. Specimens were tested for anti-HPV-16 and anti-HPV-18 immunoglobulin G (IgG) levels by an L1 virus-like particle-based enzyme-linked immunosorbent assay. All participants developed detectable serum anti-HPV-16 and anti-HPV-18 antibodies, and most had detectable antibodies in both oral specimen types at month 7 (HPV-16 was detected in 93.2% of mouthwash specimens and 95.7% of sponge specimens; HPV-18 was detected in 72.1% and 65.5%, respectively). Antibody concentrations in saliva were approximately 3 logs lower than in serum. HPV-16- and HPV-18-specific antibody levels, normalized to total IgG levels, in both oral specimen types at month 7 were significantly correlated with serum levels (for HPV-16, ρ was 0.90 for mouthwash specimens and 0.92 for sponge specimens; for HPV-18, ρ was 0.89 and 0.86, respectively). This is the first study demonstrating that vaccination of males with Gardasil induces HPV antibody levels at the oral cavity that correlate with circulating levels. © 2016 World Health Organization; licensee Oxford Journals.

  9. α7 Nicotinic acetylcholine receptor-specific antibody induces inflammation and amyloid β42 accumulation in the mouse brain to impair memory.

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    Olena Lykhmus

    Full Text Available Nicotinic acetylcholine receptors (nAChRs expressed in the brain are involved in regulating cognitive functions, as well as inflammatory reactions. Their density is decreased upon Alzheimer disease accompanied by accumulation of β-amyloid (Aβ42, memory deficit and neuroinflammation. Previously we found that α7 nAChR-specific antibody induced pro-inflammatory interleukin-6 production in U373 glioblastoma cells and that such antibodies were present in the blood of humans. We raised a hypothesis that α7 nAChR-specific antibody can cause neuroinflammation when penetrating the brain. To test this, C57Bl/6 mice were either immunized with extracellular domain of α7 nAChR subunit α7(1-208 or injected with bacterial lipopolysaccharide (LPS for 5 months. We studied their behavior and the presence of α3, α4, α7, β2 and β4 nAChR subunits, Aβ40 and Aβ42 and activated astrocytes in the brain by sandwich ELISA and confocal microscopy. It was found that either LPS injections or immunizations with α7(1-208 resulted in region-specific decrease of α7 and α4β2 and increase of α3β4 nAChRs, accumulation of Aβ42 and activated astrocytes in the brain of mice and worsening of their episodic memory. Intravenously transferred α7 nAChR-specific-antibodies penetrated the brain parenchyma of mice pre-injected with LPS. Our data demonstrate that (1 neuroinflammation is sufficient to provoke the decrease of α7 and α4β2 nAChRs, Aβ42 accumulation and memory impairment in mice and (2 α7(1-208 nAChR-specific antibodies can cause inflammation within the brain resulting in the symptoms typical for Alzheimer disease.

  10. Plasmodium falciparum Infection during Suppressive Prophylaxis with Mefloquine Does Not Induce an Antibody Response to Merozoite Surface Protein-1(42)

    Science.gov (United States)

    Moon, James E.; Deye, Gregory A.; Miller, Lori; Fracisco, Susan; Miller, R. Scott; Tosh, Donna; Cummings, James F.; Ohrt, Colin; Magill, Alan J.

    2011-01-01

    A sensitive biomarker of malaria infection would obviate the need for placebo control arms in clinical trials of malaria prophylactic drugs. Antibodies to the 42-kDa fragment of merozoite surface protein-1 (MSP142) have been identified as a potential marker of malaria exposure in individuals receiving prophylaxis with mefloquine. We conducted an open-label trial to determine the sensitivity of seroconversion to MSP142, defined as a fourfold rise in enzyme-linked immunosorbant assay (ELISA) titer, among 23 malaria naïve volunteers receiving mefloquine prophylaxis and 6 controls after Plasmodium falciparum sporozoite challenge. All members of the control cohort but none of the mefloquine cohort developed patent parasitemia. Four of six controls but zero of the mefloquine cohort seroconverted to MSP142. We conclude that malaria infection during suppressive prophylaxis does not induce antibody response to the blood-stage antigen MSP142 in a malaria-naïve study population. PMID:21540397

  11. Intranasally administered Endocine formulated 2009 pandemic influenza H1N1 vaccine induces broad specific antibody responses and confers protection in ferrets.

    Science.gov (United States)

    Maltais, Anna-Karin; Stittelaar, Koert J; Veldhuis Kroeze, Edwin J B; van Amerongen, Geert; Dijkshoorn, Marcel L; Krestin, Gabriel P; Hinkula, Jorma; Arwidsson, Hans; Lindberg, Alf; Osterhaus, Albert D M E

    2014-05-30

    Influenza is a contagious respiratory disease caused by an influenza virus. Due to continuous antigenic drift of seasonal influenza viruses, influenza vaccines need to be adjusted before every influenza season. This allows annual vaccination with multivalent seasonal influenza vaccines, recommended especially for high-risk groups. There is a need for a seasonal influenza vaccine that induces broader and longer lasting protection upon easy administration. Endocine is a lipid-based mucosal adjuvant composed of endogenous lipids found ubiquitously in the human body. Intranasal administration of influenza antigens mixed with this adjuvant has been shown to induce local and systemic immunity as well as protective efficacy against homologous influenza virus challenge in mice. Here we used ferrets, an established animal model for human influenza virus infections, to further investigate the potential of Endocine as an adjuvant. Intranasal administration of inactivated pandemic H1N1/California/2009 split antigen or whole virus antigen mixed with Endocine induced high levels of serum hemagglutination inhibition (HI) and virus neutralization (VN) antibody titers that were also cross reactive against distant swine viruses of the same subtype. HI and VN antibody titers were already demonstrated after a single nasal immunization. Upon intratracheal challenge with a homologous challenge virus (influenza virus H1N1/The Netherlands/602/2009) immunized ferrets were fully protected from virus replication in the lungs and largely protected against body weight loss, virus replication in the upper respiratory tract and pathological changes in the respiratory tract. Endocine formulated vaccines containing split antigen induced higher HI and VN antibody responses and better protection from body weight loss and virus shedding in the upper respiratory tract than the Endocine formulated vaccine containing whole virus antigen. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All

  12. Trivalent influenza vaccine-induced antibody response to circulating influenza a (H3N2) viruses in 2010/11 and 2011/12 seasons.

    Science.gov (United States)

    Hiroi, Satoshi; Morikawa, Saeko; Nakata, Keiko; Maeda, Akiko; Kanno, Tsuneji; Irie, Shin; Ohfuji, Satoko; Hirota, Yoshio; Kase, Tetsuo

    2015-01-01

    To evaluate antibody response induced by trivalent inactivated influenza vaccine (TIV) against circulating influenza A (H3N2) strains in healthy adults during the 2010/11 and 2011/12 seasons, a hemagglutination-inhibition (HI) assay was utilized to calculate geometric mean antibody titer (GMT), seroprotection rate (post vaccination HI titers of ≥1 :40), and seroresponse rate (4-fold increase in antibody level). In the 2010/11 season, GMT increased 1.8- to 2.0-fold following the first dose of TIV against 3 circulating strains and 2.2-fold following the second compared to before vaccination. The seroresponse rate ranged from 22% to 26% following the first dose of TIV and from 31% to 33% following the second (n = 54 ). The seroprotection rate increased from a range of 6% to 13% to a range of 26% to 33% following the first dose of TIV and to a range of 37% to 42% following the second (n = 54 ). In the 2011/12 season, GMT increased 1.4-fold against A/Osaka/110/2011 and 1.8-fold against A/Osaka/5/2012. For A/Osaka/110/2011, the seroresponse rate was 29%, and the seroprotection rate increased from 26% to 55% following vaccination (n = 31 ). For A/Osaka/5/2012, the seroresponse rate was 26%, and the seroprotection rate increased from 68% to 84% following vaccination (n = 31 ). HI assays with reference antisera demonstrated that the strains in the 2011/12 season were antigenically distinct from vaccine strain (A/Victoria/210/2009). In conclusion, the vaccination increased the seroprotection rate against circulating H3N2 strains in the 2010/11 and 2011/12 seasons. Vaccination of TIV might have potential to induce reactive antibodies against antigenically distinct circulating H3N2 viruses.

  13. Intra-articular administration of an antibody against CSF-1 receptor reduces pain-related behaviors and inflammation in CFA-induced knee arthritis.

    Science.gov (United States)

    Alvarado-Vazquez, P A; Morado-Urbina, C E; Castañeda-Corral, G; Acosta-Gonzalez, R I; Kitaura, H; Kimura, K; Takano-Yamamoto, T; Jiménez-Andrade, J M

    2015-01-01

    Several studies have shown that blockade of colony stimulating factor-1 (CSF-1) or its receptor (CSF-1R) inhibits disease progression in rodent models of rheumatoid arthritis (RA); however, the role of the CSF-1/CSF-1R pathway in RA-induced pain and functional deficits has not been studied. Thus, we examined the effect of chronic intra-articular administration of a monoclonal anti-CSF-1R antibody (AFS98) on spontaneous pain, knee edema and functional disabilities in mice with arthritis. Unilateral arthritis was produced by multiple injections of complete Freund's adjuvant (CFA) into the right knee joint of adult male ICR mice. CFA-injected mice were then treated twice weekly from day 10 until day 25 with anti-CSF-1R antibody (3 and 10 μg/5 μL per joint), isotype control (rat IgG 10 μg/5 μL per joint) or PBS (5 μl/joint). Knee edema, spontaneous flinching, vertical rearing and horizontal exploratory activity were assessed at different days. Additionally, counts of peripheral leukocytes and body weight were measured to evaluate general health status. Intra-articular treatment with anti-CSF-1R antibody significantly increased horizontal exploratory activity and vertical rearing as well as reduced spontaneous flinching behavior and knee edema as compared to CFA-induced arthritis mice treated with PBS. Treatment with this antibody neither significantly affect mouse body weight nor the number of peripheral leukocytes. These results suggest that blockade of CSF-1R at the initial injury site (joint) could represent a therapeutic alternative for improving the functional disabilities and attenuating pain and inflammation in patients with RA. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Whole-Chain Tick Saliva Proteins Presented on Hepatitis B Virus Capsid-Like Particles Induce High-Titered Antibodies with Neutralizing Potential.

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    Philipp Kolb

    Full Text Available Ticks are vectors for various, including pathogenic, microbes. Tick saliva contains multiple anti-host defense factors that enable ticks their bloodmeals yet also facilitate microbe transmission. Lyme disease-causing borreliae profit specifically from the broadly conserved tick histamine release factor (tHRF, and from cysteine-rich glycoproteins represented by Salp15 from Ixodes scapularis and Iric-1 from Ixodes ricinus ticks which they recruit to their outer surface protein C (OspC. Hence these tick proteins are attractive targets for anti-tick vaccines that simultaneously impair borrelia transmission. Main obstacles are the tick proteins´ immunosuppressive activities, and for Salp15 orthologs, the lack of efficient recombinant expression systems. Here, we exploited the immune-enhancing properties of hepatitis B virus core protein (HBc derived capsid-like particles (CLPs to generate, in E. coli, nanoparticulate vaccines presenting tHRF and, as surrogates for the barely soluble wild-type proteins, cysteine-free Salp15 and Iric-1 variants. The latter CLPs were exclusively accessible in the less sterically constrained SplitCore system. Mice immunized with tHRF CLPs mounted a strong anti-tHRF antibody response. CLPs presenting cysteine-free Salp15 and Iric-1 induced antibodies to wild-type, including glycosylated, Salp15 and Iric-1. The broadly distributed epitopes included the OspC interaction sites. In vitro, the anti-Salp15 antibodies interfered with OspC binding and enhanced human complement-mediated killing of Salp15 decorated borreliae. A mixture of all three CLPs induced high titered antibodies against all three targets, suggesting the feasibility of combination vaccines. These data warrant in vivo validation of the new candidate vaccines´ protective potential against tick infestation and Borrelia transmission.

  15. Curcumin induced nanoscale CD44 molecular redistribution and antigen-antibody interaction on HepG2 cell surface

    International Nuclear Information System (INIS)

    Wang Mu; Ruan Yuxia; Xing Xiaobo; Chen Qian; Peng, Yuan; Cai Jiye

    2011-01-01

    Graphical abstract: Highlights: → In this study, we investigate the changes of CD44 expression and distribution on HepG2 cells after curcumin treatment. → We find curcumin is able to change the morphology and ultrastructure of HepG2 cells. → Curcumin can reduce the expression of CD44 molecules and induce the nanoscale molecular redistribution on cell surface. → The binding force between CD44-modified AFM tip and the HepG2 cell surface decreases after curcumin-treatment. - Abstract: The cell surface glycoprotein CD44 was implicated in the progression, metastasis and apoptosis of certain human tumors. In this study, we used atomic force microscope (AFM) to monitor the effect of curcumin on human hepatocellular carcinoma (HepG2) cell surface nanoscale structure. High-resolution imaging revealed that cell morphology and ultrastructure changed a lot after being treated with curcumin. The membrane average roughness increased (10.88 ± 4.62 nm to 129.70 ± 43.72 nm) and the expression of CD44 decreased (99.79 ± 0.16% to 75.14 ± 8.37%). Laser scanning confocal microscope (LSCM) imaging showed that CD44 molecules were located on the cell membrane. The florescence intensity in control group was weaker than that in curcumin treated cells. Most of the binding forces between CD44 antibodies and untreated HepG2 cell membrane were around 120-220 pN. After being incubated with curcumin, the major forces focused on 70-150 pN (10 μM curcumin-treated) and 50-120 pN (20 μM curcumin-treated). These results suggested that, as result of nanoscale molecular redistribution, changes of the cell surface were in response to external treatment of curcumin. The combination of AFM and LSCM could be a powerful method to detect the distribution of cell surface molecules and interactions between molecules and their ligands.

  16. A conserved multi-gene family induces cross-reactive antibodies effective in defense against Plasmodium falciparum.

    Directory of Open Access Journals (Sweden)

    Subhash Singh

    Full Text Available BACKGROUND: Two related merozoite surface proteins, MSP3 and MSP6, have previously been identified as targets of antibody-dependent cellular inhibition (ADCI, a protective mechanism against Plasmodium falciparum malaria. Both MSP3 and MSP6 share a common characteristic small N-terminal signature amino-acid stretch (NLRNA/G, a feature similar to MSP3-like orthologs identified in other human and primate malaria parasites. METHODS/RESULTS: This signature amino-acid sequence led to the identification of eight ORFs contiguously located on P. falciparum chromosome 10. Our subsequent investigations on their expression, localization, sequence conservation, epitope sharing, immunogenicity and the functional role of antibodies in defense are reported here. Six members of P. falciparum MSP3-multigene family share similar sequence organization within their C-terminal regions, are simultaneously expressed as merozoite surface proteins and are highly conserved among parasite isolates. Each of these proteins is a target of naturally occurring antibodies effective at parasite killing in ADCI assays. Moreover, both naturally occurring antibodies and those generated by immunization display cross-reactivity with other members of the family and exhibit varied binding avidities. CONCLUSIONS/SIGNIFICANCE: The unusual characteristics of the MSP3 multi-gene family lead us to hypothesize that the simultaneous expression of targets eliciting cross-reactive antibody responses capable of controlling parasite densities could represent an immune process selected through evolution to maintain homeostasis between P. falciparum and human hosts; a process that allows the continuous transmission of the parasite without killing the host. Our observations also have practical consequences for vaccine development by suggesting MSP3 vaccine efficacy might be improved when combined with the various C-terminus regions of the MSP3 family members to generate a wider range of antibodies

  17. Potential role of specific antibodies as important vaccine induced protective mechanism against Aeromonas salmonicida in rainbow trout.

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    Kasper Rømer Villumsen

    Full Text Available Furunculosis caused by infection with Aeromonas salmonicida subsp. salmonicida has been a known threat to aquaculture for more than a century. Efficient prophylactic approaches against this disease are essential for continued growth of salmonid aquaculture. Since the introduction of successful oil-adjuvanted vaccines in the early 1990's, a number of studies have been published on the protective as well as adverse effects of these vaccines. Most studies focus on vaccination of salmon (Salmo salar. However, rainbow trout (Oncorhynchus mykiss are also very susceptible to infection and are vaccinated accordingly. In this study we have examined the protection against infection with a Danish strain of A. salmonicida in both vaccinated and non-vaccinated rainbow trout. A commercial and an experimental auto-vaccine were tested. The protective effects of the vaccines were evaluated through an A. salmonicida challenge 18 weeks post vaccination. Both vaccines resulted in a significantly increased survival in the vaccinated fish during a 28 day challenge period relative to non-vaccinated fish (P = 0.01 and P = 0.001 for the commercial and experimental vaccine, respectively. Throughout the entire experiment, the presence of specific antibodies in plasma was monitored using ELISA. A significant increase in specific antibody levels was seen in fish vaccinated with both vaccines during the 18 weeks between vaccination and challenge. Within 3 days post challenge, a significant decrease in specific antibodies occurred in vaccinated fish. A positive correlation was found between mean levels of specific antibodies pre challenge and overall survival. This correlation, along with the observed depletion of antibodies during the initial phase of infection, suggests that specific antibodies play an essential role in vaccine mediated protection against A. salmonicida in rainbow trout.

  18. A role for uric acid and the Nalp3 inflammasome in antiphospholipid antibody-induced IL-1β production by human first trimester trophoblast.

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    Melissa J Mulla

    Full Text Available Women with antiphospholipid syndrome (APS are at risk of recurrent pregnancy loss and obstetrical disorders, such as preeclampsia and intrauterine growth restriction (IUGR. Antiphospholipid antibodies (aPL directly target the placenta by binding beta2-glycoprotein I (β2GPI expressed on the trophoblast. We recently demonstrated in human first trimester trophoblast cells that anti-β2GPI antibodies (Abs induce the secretion of IL-1β in a Toll-like receptor 4 (TLR4-dependent manner. IL-1β secretion requires processing of pro-IL-1β and this is mediated by the inflammasome, a complex of Nalp3, apoptosis-associated speck-like protein containing a CARD (ASC and caspase-1. The objective of this study was to determine if aPL induce IL-1β production in trophoblast via the inflammasome. Using a human first trimester trophoblast cell line, we demonstrated that a mouse anti-β2GPI mAb and human polyclonal aPL-IgG induce IL-1β processing and secretion, which was partially blocked upon caspase-1 inhibition. Nalp3 and ASC knockdown also attenuated anti-β2GPI Ab-induced IL-1β secretion. Furthermore, aPL stimulated the production of uric acid in a TLR4-dependent manner; and inhibition of uric acid prevented aPL-induced IL-1β production by the trophoblast. These findings demonstrate that aPL, via TLR4 activation, induce a uric acid response in human trophoblast, which in turn activates the Nalp3/ASC inflammasome leading to IL-1β processing and secretion. This novel mechanism may account for the inflammation at the maternal-fetal interface, which causes placental dysfunction and increases the risk of adverse pregnancy outcome in patients with APS.

  19. A novel replication-competent vaccinia vector MVTT is superior to MVA for inducing high levels of neutralizing antibody via mucosal vaccination.

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    Xiaoxing Huang

    Full Text Available Mucosal vaccination offers great advantage for inducing protective immune response to prevent viral transmission and dissemination. Here, we report our findings of a head-to-head comparison of two viral vectors modified vaccinia Ankara (MVA and a novel replication-competent modified vaccinia Tian Tan (MVTT for inducing neutralizing antibodies (Nabs via intramuscular and mucosal vaccinations in mice. MVTT is an attenuated variant of the wild-type VTT, which was historically used as a smallpox vaccine for millions of Chinese people. The spike glycoprotein (S of SARS-CoV was used as the test antigen after the S gene was constructed in the identical genomic location of two vectors to generate vaccine candidates MVTT-S and MVA-S. Using identical doses, MVTT-S induced lower levels ( approximately 2-3-fold of anti- SARS-CoV neutralizing antibodies (Nabs than MVA-S through intramuscular inoculation. MVTT-S, however, was capable of inducing consistently 20-to-100-fold higher levels of Nabs than MVA-S when inoculated via either intranasal or intraoral routes. These levels of MVTT-S-induced Nab responses were substantially (approximately 10-fold higher than that induced via the intramuscular route in the same experiments. Moreover, pre-exposure to the wild-type VTT via intranasal or intraoral route impaired the Nab response via the same routes of MVTT-S vaccination probably due to the pre-existing anti-VTT Nab response. The efficacy of intranasal or intraoral vaccination, however, was still 20-to-50-fold better than intramuscular inoculation despite the subcutaneous pre-exposure to wild-type VTT. Our data have implications for people who maintain low levels of anti-VTT Nabs after historical smallpox vaccination. MVTT is therefore an attractive live viral vector for mucosal vaccination.

  20. Antibody and T cell responses induced in chickens immunized with avian influenza virus N1 and NP DNA vaccine with chicken IL-15 and IL-18.

    Science.gov (United States)

    Lim, Kian-Lam; Jazayeri, Seyed Davoud; Yeap, Swee Keong; Mohamed Alitheen, Noorjahan Banu; Bejo, Mohd Hair; Ideris, Aini; Omar, Abdul Rahman

    2013-12-01

    We had examined the immunogenicity of a series of plasmid DNAs which include neuraminidase (NA) and nucleoprotein (NP) genes from avian influenza virus (AIV). The interleukin-15 (IL-15) and interleukin-18 (IL-18) as genetic adjuvants were used for immunization in combination with the N1 and NP AIV genes. In the first trial, 8 groups of chickens were established with 10 specific-pathogen-free (SPF) chickens per group while, in the second trial 7 SPF chickens per group were used. The overall N1 enzyme-linked immunosorbent assay (ELISA) titer in chickens immunized with the pDis/N1+pDis/IL-15 was higher compared to the chickens immunized with the pDis/N1 and this suggesting that chicken IL-15 could play a role in enhancing the humoral immune response. Besides that, the chickens that were immunized at 14-day-old (Trial 2) showed a higher N1 antibody titer compared to the chickens that were immunized at 1-day-old (Trial 1). Despite the delayed in NP antibody responses, the chickens co-administrated with IL-15 were able to induce earlier and higher antibody response compared to the pDis/NP and pDis/NP+pDis/IL-18 inoculated groups. The pDis/N1+pDis/IL-15 inoculated chickens also induced higher CD8+ T cells increase than the pDis/N1 group in both trials (P0.05) in inducing CD4+ and CD8+ T cells when co-administered with the pDis/IL-18 in both trials in comparison to the pDis/NP. Our data suggest that the pDis/N1+pDis/IL-15 combination has the potential to be used as a DNA vaccine against AIV in chickens. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. An Fc engineering approach that modulates antibody-dependent cytokine release without altering cell-killing functions.

    Science.gov (United States)

    Kinder, Michelle; Greenplate, Allison R; Strohl, William R; Jordan, Robert E; Brezski, Randall J

    2015-01-01

    Cytotoxic therapeutic monoclonal antibodies (mAbs) often mediate target cell-killing by eliciting immune effector functions via Fc region interactions with cellular and humoral components of the immune system. Key functions include antibody-dependent cell-mediated cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and complement-dependent cytotoxicity (CDC). However, there has been increased appreciation that along with cell-killing functions, the induction of antibody-dependent cytokine release (ADCR) can also influence disease microenvironments and therapeutic outcomes. Historically, most Fc engineering approaches have been aimed toward modulating ADCC, ADCP, or CDC. In the present study, we describe an Fc engineering approach that, while not resulting in impaired ADCC or ADCP, profoundly affects ADCR. As such, when peripheral blood mononuclear cells are used as effector cells against mAb-opsonized tumor cells, the described mAb variants elicit a similar profile and quantity of cytokines as IgG1. In contrast, although the variants elicit similar levels of tumor cell-killing as IgG1 with macrophage effector cells, the variants do not elicit macrophage-mediated ADCR against mAb-opsonized tumor cells. This study demonstrates that Fc engineering approaches can be employed to uncouple macrophage-mediated phagocytic and subsequent cell-killing functions from cytokine release.

  2. Inhibition, by vinca alkaloids and colchicine, of antigenic modulation induced by anti-CD19 monoclonal antibodies

    NARCIS (Netherlands)

    de Rie, M. A.; Zeijlemaker, W. P.; von dem Borne, A. E.

    1988-01-01

    Several clinical trials have been reported in which monoclonal antibodies (McAb) were used for therapy of lymphoid malignancies. Such trials have shown that infusion of McAb recognizing lymphoid antigens, is well-tolerated, and leads to the coating of tumor cells and tumor regression in some

  3. Combination of two anti-CD5 monoclonal antibodies synergistically induces complement-dependent cytotoxicity of chronic lymphocytic leukaemia cells

    DEFF Research Database (Denmark)

    Klitgaard, Josephine L; Koefoed, Klaus; Geisler, Christian

    2013-01-01

    The treatment of chronic lymphocytic leukaemia (CLL) has been improved by introduction of monoclonal antibodies (mAbs) that exert their effect through secondary effector mechanisms. CLL cells are characterized by expression of CD5 and CD23 along with CD19 and CD20, hence anti-CD5 Abs that engage...

  4. ApoE Receptor 2 mediates trophoblast dysfunction and pregnancy complications induced by antiphospholipid antibodies in mice

    NARCIS (Netherlands)

    Ulrich, Victoria; Gelber, Shari E; Vukelic, Milena; Sacharidou, Anastasia; Herz, Joachim; Urbanus, Rolf T; de Groot, Philip G; Natale, David R; Harihara, Anirudha; Redecha, Patricia; Abrahams, Vikki M; Shaul, Philip W; Salmon, Jane E; Mineo, Chieko

    OBJECTIVE: Pregnancies in women with the antiphospholipid syndrome (APS) are frequently complicated by fetal loss and intrauterine growth restriction (IUGR). How circulating antiphospholipid antibodies (aPL) cause pregnancy complications in APS is poorly understood. We sought to determine if the LDL

  5. Rhinovirus-induced VP1-specific Antibodies are Group-specific and Associated With Severity of Respiratory Symptoms

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    Katarzyna Niespodziana

    2015-01-01

    Interpretation: Our results demonstrate that increases of antibodies towards the VP1 N-terminus are group-specific and associated with severity of respiratory symptoms and suggest that it may be possible to develop serological tests for identifying causative RV groups.

  6. Antibody-induced activation of the epidermal growth factor receptor tyrosine kinase requires the presence of detergent

    NARCIS (Netherlands)

    Spaargaren, M.; Defize, L. H.; de Laat, S. W.; Boonstra, J.

    1990-01-01

    Activation of the epidermal growth factor receptor (EGF-R) tyrosine kinase was investigated in membrane preparations as well as intact A431 cells, using anti-EGF-R antibodies directed against extra- and intracellular receptor domains. In vitro assay conditions were mimicked on whole cells by a mild

  7. Bacterial superglue generates a full-length circumsporozoite protein virus-like particle vaccine capable of inducing high and durable antibody responses

    DEFF Research Database (Denmark)

    Janitzek, Christoph M; Matondo, Sungwa; Thrane, Susan

    2016-01-01

    modified to display one SpyTag per VLP subunit. To evaluate the VLP-display effect, the immunogenicity of the VLP vaccine was tested in mice and compared to a control vaccine containing AP205 VLPs plus unconjugated CSP. RESULTS: Full-length CSP was conjugated at high density (an average of 112 CSP...... production of IgG2a antibodies, which has been linked with a more efficient clearing of intracellular parasite infection. CONCLUSION: This study demonstrates that the high-density display of CSP on SpyTag-VLPs, significantly increases the level and quality of the vaccine-induced humoral response, compared...

  8. Oral vaccination of mice with recombinant Schistosoma japonicum proteins induces specific anti-parasite antibodies and damage to adult worms after a challenge infection.

    Science.gov (United States)

    Yang, W; Gobert, G N; McManus, D P

    1997-07-01

    Mucosal immunisation by the oral route represents a cheap and simple method for delivering protective antigens to a host against gastrointestinal and respiratory pathogens. In the case of schistosome (bloodfluke) worms, 2 life-cycle stages may be exposed to the host's mucosa; the larval schistosomulum is exposed to the respiratory mucosa and, depending on the species, the egg may come into contact with the intestinal or urinogenital mucosa. Both IgA and some Isotypes of IgG have been implicated in protective immunity against schistosomiasis in humans and in experimental animal models. We have used a novel approach to determine whether schistosome-specific antibodies and protective immunity could be generated in mice by oral administration of bacterial lysates containing recombinant Schistosoma japonicum proteins. The mice produced specific antibodies to paramyosin and GST26, 2 important vaccine candidates for schistosomiasis, but there was no significant reduction in worm burdens in groups of mice immunised with either protein. Significantly, however, transmission electron microscopy revealed damage to the teguments of adult female and male S. japonicum worms obtained from mice vaccinated with recombinant paramyosin; there was also extensive damage to the tegument of male worms recovered from mice vaccinated with recombinant GST26. Our observations that oral vaccination with bacterial lysates containing recombinant proteins induced particular classes and subclasses of circulating antibodies with resultant damage to the surface of adult worms may have important implications for the future development of oral vaccines against a systemic infection such as schistosomiasis.

  9. Vaccination of dogs with canine parvovirus type 2b (CPV-2b) induces neutralising antibody responses to CPV-2a and CPV-2c.

    Science.gov (United States)

    Wilson, Stephen; Illambas, Joanna; Siedek, Elisabeth; Stirling, Catrina; Thomas, Anne; Plevová, Edita; Sture, Gordon; Salt, Jeremy

    2014-09-22

    Since the identification of canine parvovirus type 2, three variants have subsequently been observed differing from the historical CPV-2 and each other by 1-2 amino acids only. As a result there has been considerable research into differential diagnostics, with some researchers indicating there is a need for new vaccines containing different strains of CPV-2. In this study we investigated whether vaccination with a CPV-2b containing vaccine would induce cross-reactive antibody responses to the other CPV-2 variants. Two studies where dogs were vaccinated with a multivalent vaccine, subsequently challenged with CPV-2b and sera samples analysed are presented. Six week old pups with defined serological status were vaccinated twice, three weeks apart and challenged either 5 weeks (MDA override study) or one year after vaccination (duration of immunity study). Sera samples were collected before each vaccination and at periods throughout each study. In each study the antibody profiles were very similar; serological responses against CPV-2a, CPV-2b and CPV-2c were higher than those for CPV-2. Nevertheless, responses against CPV-2 were well above levels considered clinically protective. In each study dogs also showed a rapid increase in antibody titres following vaccination, reached a plateau following second vaccination with a slight decline to challenge after which rapid anamnestic responses were seen. Evaluation of the serological responses suggests vaccination with CPV-2b would cross-protect against CPV-2a and CPV-2c, as well as against CPV-2 which is now extinct in the field. In conclusion we have demonstrated that vaccination of minimum aged dogs with a multivalent vaccine containing the CPV-2b variant strain will induce serological responses which are cross-reactive against all currently circulating field strains, CPV-2a and CPV-2c, and the now extinct field strain CPV-2. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. A case of propylthiouracil-induced antineutrophilic cytoplasmic antibody-positive vasculitis successfully treated with radioactive iodine

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    C. Bes

    2013-07-01

    Full Text Available Antineutrophilic cytoplasmic antibody (ANCA associated vasculitis is one of the rare complications of propylthiouracil treatment. Having a variable clinical spectrum, it may be presented with both skin limited vasculitis and life-threatening systemic vasculitis. In this study, we present a case that developed ANCA-positive vasculitis with skin and kidney involvement (hematuria and proteinuria six months after propylthiouracil treatment was initiated for toxic nodular goiter. Proteinuria recovered dramatically subsequent to radioactive iodine treatment following ceasing the drug.

  11. AAVrh.10-Mediated Expression of an Anti-Cocaine Antibody Mediates Persistent Passive Immunization That Suppresses Cocaine-Induced Behavior

    OpenAIRE

    Rosenberg, Jonathan B.; Hicks, Martin J.; De, Bishnu P.; Pagovich, Odelya; Frenk, Esther; Janda, Kim D.; Wee, Sunmee; Koob, George F.; Hackett, Neil R.; Kaminsky, Stephen M.; Worgall, Stefan; Tignor, Nicole; Mezey, Jason G.; Crystal, Ronald G.

    2012-01-01

    Cocaine addiction is a major problem affecting all societal and economic classes for which there is no effective therapy. We hypothesized an effective anti-cocaine vaccine could be developed by using an adeno-associated virus (AAV) gene transfer vector as the delivery vehicle to persistently express an anti-cocaine monoclonal antibody in vivo, which would sequester cocaine in the blood, preventing access to cognate receptors in the brain. To accomplish this, we constructed AAVrh.10antiCoc.Mab...

  12. Recombinant Protein Truncation Strategy for Inducing Bactericidal Antibodies to the Macrophage Infectivity Potentiator Protein of Neisseria meningitidis and Circumventing Potential Cross-Reactivity with Human FK506-Binding Proteins

    OpenAIRE

    Bielecka, Magdalena K.; Devos, Nathalie; Gilbert, Mélanie; Hung, Miao-Chiu; Weynants, Vincent; Heckels, John E.; Christodoulides, Myron

    2014-01-01

    A recombinant macrophage infectivity potentiator (rMIP) protein of Neisseria meningitidis induces significant serum bactericidal antibody production in mice and is a candidate meningococcal vaccine antigen. However, bioinformatics analysis of MIP showed some amino acid sequence similarity to human FK506-binding proteins (FKBPs) in residues 166 to 252 located in the globular domain of the protein. To circumvent the potential concern over generating antibodies that could recognize human protein...

  13. Antiprothrombin Antibodies

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    Polona Žigon

    2015-05-01

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

  14. Antibody responses induced by Leish-Tec®, an A2-based vaccine for visceral leishmaniasis, in a heterogeneous canine population.

    Science.gov (United States)

    Testasicca, Miriam C de Souza; dos Santos, Mariana Silva; Machado, Leopoldo Marques; Serufo, Angela Vieira; Doro, Daniel; Avelar, Daniel; Tibúrcio, Ana Maria Leonardi; Abrantes, Christiane de Freitas; Machado-Coelho, George Luiz Lins; Grimaldi, Gabriel; Gazzinelli, Ricardo Tostes; Fernandes, Ana Paula

    2014-08-29

    Zoonotic visceral leishmaniasis (VL) is a widespread disease, and dogs are the main reservoirs for human parasite transmission. Hence, development of an effective vaccine that prevents disease and reduces the transmission of VL is required. As euthanasia of seropositive dogs is recommended in Brazil for VL epidemiological control, to include anti-VL canine vaccines as a mass control measure it is necessary to characterize the humoral responses induced by vaccination and if they interfere with the reactivity of vaccinated dogs in serological diagnostic tests. Leish-Tec(®) is an amastigote-specific A2 recombinant protein vaccine against canine visceral leishmaniasis (CVL) that is commercially available in Brazil. Here, we tested the immunogenicity of Leish-Tec(®) in a heterogeneous dog population by measuring A2-specific antibody responses. Healthy dogs (n=140) of various breeds were allocated to two groups: one group received Leish-Tec(®) (n=70), and the other group received a placebo (n=70). Anti-A2 or anti-Leishmania promastigote antigen (LPA) antibody levels were measured by ELISA in serum samples collected before and after vaccination. An immunochromatographic test (DPP) based on the recombinant K28 antigen was also used for serodiagnosis of CVL. Vaccinated animals, except one, remained seronegative for anti-LPA total IgG and anti-K28 antibodies. Conversely, seropositivity for anti-A2 total IgG antibodies was found in 98% of animals after vaccination. This value decreased to 81.13% at 6 months before rising again (98%), after the vaccination boost. Anti-A2 IgG2 and IgG1 titers were also increased in vaccinated animals relative to control animals. These data indicate that Leish-Tec(®) is immunogenic for dogs of different genetic backgrounds and that humoral responses induced by vaccination can be detected by A2-ELISA, but do not interfere with the LPA-ELISA and DPP diagnostic tests for CVL. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Persistent Low-Level Replication of SIVΔnef Drives Maturation of Antibody and CD8 T Cell Responses to Induce Protective Immunity against Vaginal SIV Infection.

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    Sama Adnan

    2016-12-01

    Full Text Available Defining the correlates of immune protection conferred by SIVΔnef, the most effective vaccine against SIV challenge, could enable the design of a protective vaccine against HIV infection. Here we provide a comprehensive assessment of immune responses that protect against SIV infection through detailed analyses of cellular and humoral immune responses in the blood and tissues of rhesus macaques vaccinated with SIVΔnef and then vaginally challenged with wild-type SIV. Despite the presence of robust cellular immune responses, animals at 5 weeks after vaccination displayed only transient viral suppression of challenge virus, whereas all macaques challenged at weeks 20 and 40 post-SIVΔnef vaccination were protected, as defined by either apparent sterile protection or significant suppression of viremia in infected animals. Multiple parameters of CD8 T cell function temporally correlated with maturation of protection, including polyfunctionality, phenotypic differentiation, and redistribution to gut and lymphoid tissues. Importantly, we also demonstrate the induction of a tissue-resident memory population of SIV-specific CD8 T cells in the vaginal mucosa, which was dependent on ongoing low-level antigenic stimulation. Moreover, we show that vaginal and serum antibody titers inversely correlated with post-challenge peak viral load, and we correlate the accumulation and affinity maturation of the antibody response to the duration of the vaccination period as well as to the SIVΔnef antigenic load. In conclusion, maturation of SIVΔnef-induced CD8 T cell and antibody responses, both propelled by viral persistence in the gut mucosa and secondary lymphoid tissues, results in protective immune responses that are able to interrupt viral transmission at mucosal portals of entry as well as potential sites of viral dissemination.

  16. A chimeric haemagglutinin-based influenza split virion vaccine adjuvanted with AS03 induces protective stalk-reactive antibodies in mice.

    Science.gov (United States)

    Nachbagauer, Raffael; Kinzler, David; Choi, Angela; Hirsh, Ariana; Beaulieu, Edith; Lecrenier, Nicolas; Innis, Bruce L; Palese, Peter; Mallett, Corey P; Krammer, Florian

    2016-01-01

    Seasonal influenza virus vaccines are generally effective at preventing disease, but need to be well matched to circulating virus strains for maximum benefit. Influenza viruses constantly undergo antigenic changes because of their high mutation rate in the immunodominant haemagglutinin (HA) head domain, which necessitates annual re-formulation and re-vaccination for continuing protection. In case of pandemic influenza virus outbreaks, new vaccines need to be produced and quickly distributed. Novel influenza virus vaccines that redirect the immune response towards more conserved epitopes located in the HA stalk domain may remove the need for annual vaccine re-formulation and could also protect against emergent pandemic strains to which the human population is immunologically naive. One approach to create such universal influenza virus vaccines is the use of constructs expressing chimeric HAs. By sequential immunization with vaccine strains expressing the same conserved HA stalk domain and exotic HA heads to which the host is naive, antibodies against the stalk can be boosted to high titres. Here we tested a monovalent chimeric HA-based prototype universal influenza virus split virion vaccine candidate with and without AS03 adjuvant in primed mice. We found that the chimeric HA-based vaccination regimen induced higher stalk antibody titres than the seasonal vaccine. The stalk antibody responses were long lasting, cross-reactive to distantly related HAs and provided protection in vivo in a serum transfer challenge model. The results of this study are promising and support further development of a universal influenza vaccine candidate built on the chimeric HA technology platform.

  17. Antibody Production and Th1-biased Response Induced by an Epitope Vaccine Composed of Cholera Toxin B Unit and Helicobacter pylori Lpp20 Epitopes.

    Science.gov (United States)

    Li, Yan; Chen, Zhongbiao; Ye, Jianbin; Ning, Lijun; Luo, Jun; Zhang, Lili; Jiang, Yin; Xi, Yue; Ning, Yunshan

    2016-06-01

    The epitope vaccine is an attractive potential for prophylactic and therapeutic vaccination against Helicobacter pylori (H. pylori) infection. Lpp20 is one of major protective antigens which trigger immune response after H. pylori invades host and has been considered as an excellent vaccine candidate for the control of H. pylori infection. In our previous study, one B-cell epitope and two CD4(+) T-cell epitopes of Lpp20 were identified. In this study, an epitope vaccine composed of mucosal adjuvant cholera toxin B subunit (CTB) and these three identified Lpp20 epitopes were constructed to investigate the efficacy of this epitope vaccine in mice. The epitope vaccine including CTB, one B-cell, and two CD4(+) T-cell epitopes of Lpp20 was constructed and named CTB-Lpp20, which was then expressed in Escherichia coli and used for intraperitoneal immunization in BALB/c mice. The immunogenicity, specificity, and ability to induce antibodies against Lpp20 and cytokine secretion were evaluated. After that, CTB-Lpp20 was intragastrically immunized to investigate the prophylactic and therapeutic efficacy in infected mice. The results indicated that the epitope vaccine CTB-Lpp20 possessed good immunogenicity and immunoreactivity and could elicit specific high level of antibodies against Lpp20 and the cytokine of IFN-γ and IL-17. Additionally, CTB-Lpp20 significantly decreased H. pylori colonization in H. pylori challenging mice, and the protection was correlated with IgG, IgA, and sIgA antibody and Th1-type cytokines. This study will be better for understanding the protective immunity of epitope vaccine, and CTB-Lpp20 may be an alternative strategy for combating H. pylori invasion. © 2015 John Wiley & Sons Ltd.

  18. Toll-like receptor activation enhances cell-mediated immunity induced by an antibody vaccine targeting human dendritic cells

    Directory of Open Access Journals (Sweden)

    Berger Marc A

    2007-01-01

    Full Text Available Abstract Previously, we have successfully targeted the mannose receptor (MR expressed on monocyte-derived dendritic cells (DCs using a fully human MR-specific antibody, B11, as a vehicle to deliver whole protein tumor antigens such as the human chorionic gonadotropin hormone (hCGβ. Since MRs play a role in bridging innate immunity with adaptive immunity we have explored several toll-like receptor (TLR-specific ligands that may synergize with MR targeting and be applicable as adjuvants in the clinic. We demonstrate that antigen-specific helper and cytolytic T cells from both healthy donors and cancer patients were effectively primed with B11-hCGβ-treated autologous DCs when a combination of one or several TLR ligands is used. Specifically, concomitant signaling of DCs via TLR3 with dsRNA (poly I:C and DC TLR 7/8 with Resiquimod (R-848, respectively, elicited efficient antigen presentation-mediated by MR-targeting. We demonstrate that MR and TLRs contribute towards maturation and activation of DCs by a mechanism that may be driven by a combination of adjuvant and antibody vaccines that specifically deliver antigenic targets to DCs.

  19. Preliminary application of radioimmunoscintigraphy with 99Tcm labelled anti-fibrin monoclonal antibody (SZ-63) in experimental steroid-induced osteonecrosis in rabbits

    International Nuclear Information System (INIS)

    Zhang Wei; Huang Lixin; Dong Tianhua; Yuan Changgeng

    2002-01-01

    Objective: To evaluate the feasibility of radioimmunoscintigraphy of steroid-induced osteonecrosis with 99 Tc m labelled monoclonal antibody against human fibrin (SZ-63) and to explore the mechanisms postulated in the pathogenesis of steroid-induced osteonecrosis. Methods: Experimental steroid-induced osteonecrosis was produced by intravenous horse serum combined with intraperitoneal high-dose of dexamethasone in 14 healthy adult rabbits, and then radioimmunoscintigraphy with 99 Tc m -SZ-63 was performed. The acquired images were analyzed in comparison with histopathological findings. The other 5 healthy adult rabbits received injection of normal saline instead of horse serum or steroids were used as control. Results: The histopathological observation showed that 10 of 14 model rabbits (71.43%) had osteonecrosis in the femoral head (osteonecrosis group) and no osteonecrosis signs were found in the remaining 4 model rabbits (28.57%, non-osteonecrosis group) and either in the control group. In the osteonecrosis group, the radioactivity uptake increased markedly in both ends of the femur, especially in the femoral head 4 h after injection of 99 Tc m -SZ-63. No abnormal signs were observed in both the non-osteonecrosis group and the control group. The radioactivity ratios of femoral head to trunk were 2.16 +- 0.35, 1.68 +- 0.29 and 1.57 +- 0.12 in osteonecrosis group, non-osteonecrosis group and control group, respectively. There was statistical difference between the former two groups (P 0.05). Conclusions: Steroid-induced osteonecrosis is correlative to thrombosis. Radioimmunoscintigraphy with 99 Tc m -SZ-63 could specifically detect in vivo thrombosis of the steroid-induced osteonecrosis in the rabbit models, and it may provide a great potential of early noninvasive diagnosis of osteonecrosis and screening high-risk group of steroid-induced osteonecrosis

  20. Antibodies That Block or Activate Mouse B Cell Activating Factor of the Tumor Necrosis Factor (TNF) Family (BAFF), Respectively, Induce B Cell Depletion or B Cell Hyperplasia*

    Science.gov (United States)

    Kowalczyk-Quintas, Christine; Schuepbach-Mallepell, Sonia; Vigolo, Michele; Willen, Laure; Tardivel, Aubry; Smulski, Cristian R.; Zheng, Timothy S.; Gommerman, Jennifer; Hess, Henry; Gottenberg, Jacques-Eric; Mackay, Fabienne; Donzé, Olivier

    2016-01-01

    B cell activating factor of the TNF family (BAFF), also known as B lymphocyte stimulator, is a ligand required for the generation and maintenance of B lymphocytes. In this study, the ability of different monoclonal antibodies to recognize, inhibit, or activate mouse BAFF was investigated. One of them, a mouse IgG1 named Sandy-2, prevented the binding of BAFF to all of its receptors, BAFF receptor, transmembrane activator and calcium modulating ligand interactor, and B cell maturation antigen, at a stoichiometric ratio; blocked the activity of mouse BAFF on a variety of cell-based reporter assays; and antagonized the prosurvival action of BAFF on primary mouse B cells in vitro. A single administration of Sandy-2 in mice induced B cell depletion within 2 weeks, down to levels close to those observed in BAFF-deficient mice. This depletion could then be maintained with a chronic treatment. Sandy-2 and a previously described rat IgG1 antibody, 5A8, also formed a pair suitable for the sensitive detection of endogenous circulating BAFF by ELISA or using a homogenous assay. Interestingly, 5A8 and Sandy-5 displayed activities opposite to that of Sandy-2 by stimulating recombinant BAFF in vitro and endogenous BAFF in vivo. These tools will prove useful for the detection and functional manipulation of endogenous mouse BAFF and provide an alternative to the widely used BAFF receptor-Fc decoy receptor for the specific depletion of BAFF in mice. PMID:27451394

  1. PHiD-CV induces anti-Protein D antibodies but does not augment pulmonary clearance of nontypeable Haemophilus influenzae in mice.

    Science.gov (United States)

    Siggins, Matthew K; Gill, Simren K; Langford, Paul R; Li, Yanwen; Ladhani, Shamez N; Tregoning, John S

    2015-09-11

    A recently-licensed 10-valent pneumococcal conjugate vaccine (PHiD-CV; Synflorix, GSK) uses Protein D from Haemophilus influenzae as a carrier protein. PHiD-CV therefore has the potential to provide additional protection against nontypeable H. influenzae (NTHi). NTHi frequently causes respiratory tract infections and is associated with significant morbidity and mortality worldwide and there is currently no vaccine. We developed mouse models of NTHi infection and influenza/NTHi superinfection. Mice were immunized with PHiD-CV, heat-killed NTHi, or a 13-valent pneumococcal conjugate vaccine that did not contain Protein D (PCV13; Prevenar, Pfizer) and then infected intranasally with NTHi. Infection with NTHi resulted in weight loss, inflammation and airway neutrophilia. In a superinfection model, prior infection with pandemic H1N1 influenza virus (strain A/England/195/2009) augmented NTHi infection severity, even with a lower bacterial challenge dose. Immunization with PHiD-CV produced high levels of antibodies that were specific against Protein D, but not heat-killed NTHi. Immunization with PHiD-CV led to a slight reduction in bacterial load, but no change in disease outcome. PHiD-CV induced high levels of Protein D-specific antibodies, but did not augment pulmonary clearance of NTHi. We found no evidence to suggest that PHiD-CV will offer added benefit by preventing NTHi lung infection. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Bovine Herpesvirus-4-Based Vector Delivering Peste des Petits Ruminants Virus Hemagglutinin ORF Induces both Neutralizing Antibodies and Cytotoxic T Cell Responses

    Directory of Open Access Journals (Sweden)

    Francesca Macchi

    2018-03-01

    Full Text Available Peste des Petits Ruminants Virus (PPRV is an extremely infective morbillivirus that primarily affects goats and sheep. In underdeveloped countries where livestock are the main economical resource, PPRV causes considerable economic losses. Protective live attenuated vaccines are currently available but they induce antibody responses similar to those produced in PPRV naturally infected animals. Effective vaccines able to distinguish between vaccinated and naturally infected animals are required to PPRV control and eradication programs. Hemagglutinin (H is a highly immunogenic PPRV envelope glycoprotein displaying both hemagglutinin and neuraminidase activities, playing a crucial role in virus attachment and penetration. In this study, a recombinant Bovine Herpesvirus-4 (BoHV-4-based vector delivering an optimized PPRV-Hemagglutinin expression cassette, BoHV-4-A-PPRV-H-ΔTK, was assessed in immunocompetent C57BL/6 mice. BoHV-4-A-PPRV-H-ΔTK-immunization elicited both cellular and humoral immune responses with specific T cell, cytotoxic T lymphocyte, and sero-neutralizing antibody against PPRV. These data suggest recombinant BoHV-4-A-PPRV-H-ΔTK as an effective vaccine candidate to protect against PPRV herd infection and potentially applicable for eradication programs.

  3. Comparison of serum bactericidal and antibody titers induced by two Haemophilus influenzae type b conjugate vaccines: A phase III randomized double-blind study.

    Science.gov (United States)

    Akeda, Yukihiro; Koizumi, Yuka; Takanami, Yohei; Sumino, Shuji; Hattori, Yumi; Sugizaki, Kayoko; Mitsuya, Nodoka; Oishi, Kazunori

    2018-03-14

    Haemophilus influenzae type b (Hib) conjugate vaccines have drastically reduced disease incidence worldwide. Protection against Hib infection has relied on the serum bactericidal activity (SBA) of antibodies to the Hib capsular polysaccharide (polyribosylribitol phosphate). However, licensure usually relies on measuring induction of antibodies to PRP as a surrogate for SBA. In a phase III clinical trial we compared a PRP-conjugate vaccine using the nontoxic diphtheria toxin mutant, CRM 197 , as carrier protein with the licensed tetanus toxoid conjugate when administered subcutaneously as a three dose primary series in Japanese infants. As an addition to the phase III study, we have now evaluated SBA and show PRP-CRM 197 induces higher levels of SBA than PRP-T four weeks after the primary series, with a statistically significant correlation with anti-PRP titers. This data confirms the superior immunogenicity of PRP-CRM 197 compared with PRP-T assessed as SBA following a three-dose primary series by subcutaneous administration. Clinical trial registry: Registered on ClinicalTrials.gov (NCT01379846). Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Biodistribution and PET Imaging of a Novel [(68)Ga]-Anti-CD163-Antibody Conjugate in Rats with Collagen-Induced Arthritis and in Controls

    DEFF Research Database (Denmark)

    Eichendorff, Sascha; Svendsen, Pia; Bender, Dirk

    2015-01-01

    -68 and evaluated stability and binding specificity of the conjugate ([(68)Ga]ED2) in vitro. Furthermore, tracer biodistribution was assessed in vivo in healthy rats and rats with acute collagen-induced arthritis (CIA) by MicroPET and tissue analysis. RESULTS: Radiosynthesis of [(68)Ga]ED2 antibody...... was also changed in the sense that a significantly higher liver uptake and lower spleen uptake of [(68)Ga]ED2 was measured in CIA rats that accordingly showed a corresponding change in level of CD163 expression. CONCLUSIONS: [(68)Ga]ED2 specifically binds CD163 in vitro and in vivo. Biodistribution studies...... in CIA rats suggest that this novel tool may have applications in studies of inflammatory diseases....

  5. Cross-Linking GPVI-Fc by Anti-Fc Antibodies Potentiates Its Inhibition of Atherosclerotic Plaque- and Collagen-Induced Platelet Activation

    Directory of Open Access Journals (Sweden)

    Janina Jamasbi, RPh

    2016-04-01

    Full Text Available To enhance the antithrombotic properties of recombinant glycoprotein VI fragment crystallizable (GPVI-Fc, the authors incubated GPVI-Fc with anti-human Fc antibodies to cross-link the Fc tails of GPVI-Fc. Cross-linking potentiated the inhibition of human plaque- and collagen-induced platelet aggregation by GPVI-Fc under static and flow conditions without increasing bleeding time in vitro. Cross-linking with anti-human-Fc Fab2 was even superior to anti-human-Fc immunoglobulin G (IgG. Advanced optical imaging revealed a continuous sheath-like coverage of collagen fibers by cross-linked GPVI-Fc complexes. Cross-linking of GPVI into oligomeric complexes provides a new, highly effective, and probably safe antithrombotic treatment as it suppresses platelet GPVI-plaque interaction selectively at the site of acute atherothrombosis.

  6. T-cell activation. V. Anti-major histocompatibility complex class I antibody-induced activation and clonal abortion in Jurkat T-leukaemic cells

    DEFF Research Database (Denmark)

    Claesson, M H; Dissing, S; Tscherning, T

    1993-01-01

    respectively, as well as three transfectant clones reconstituted with the appropriate TcR/CD3 cDNA. For activation, the cells were exposed to anti-TcR/CD3, anti-CD2 and anti-major histocompatibility complex (anti-MHC) class I monoclonal antibodies (mAb) respectively. Cellular activation by these mAb leading...... to an increased IL-2 secretion was preceded by a rise in [Ca2+]i and was relatively dependent on the expression of the a TcR/CD3 complex. In contrast, anti-MHC class I mAb-induced clonal abortion in Jurkat T cells may occur without previous fluctuations in [Ca2+]i and appeared to be independent of TcR/CD3...

  7. Acetylcholine receptor binding antibody-associated myasthenia gravis and rhabdomyolysis induced by nivolumab in a patient with melanoma.

    Science.gov (United States)

    Shirai, Takushi; Sano, Tasuku; Kamijo, Fuminao; Saito, Nana; Miyake, Tomomi; Kodaira, Minori; Katoh, Nagaaki; Nishie, Kenichi; Okuyama, Ryuhei; Uhara, Hisashi

    2016-01-01

    We reported an 81-year-old woman with metastatic melanoma, in whom myasthenia gravis and rhabdomyolysis developed after nivolumab monotherapy. The first symptom of myasthenia gravis was dyspnea. Ultrasonography detected hypokinesis of the bilateral diaphragm suggesting myasthenia gravis, although there was no abnormal finding of the lungs in computed tomography images. Acetylcholine receptor binding antibodies were low-titer positive in the preserved serum before administration of nivolumab, strongly suggesting that the myasthenia gravis was a nivolumab-related immune adverse event. Despite the remarkable clinical benefits of immune checkpoint inhibitors for patients with advanced melanoma, it is important to recognize unexpected immune-related adverse events. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Inhibition of the Receptor Tyrosine Kinase ROR1 by Anti-ROR1 Monoclonal Antibodies and siRNA Induced Apoptosis of Melanoma Cells

    Science.gov (United States)

    Hojjat-Farsangi, Mohammad; Ghaemimanesh, Fatemeh; Daneshmanesh, Amir Hossein; Bayat, Ali-Ahmad; Mahmoudian, Jafar; Jeddi-Tehrani, Mahmood; Rabbani, Hodjatallah; Mellstedt, Hakan

    2013-01-01

    The receptor tyrosine kinase (RTK) ROR1 is overexpressed and of importance for the survival of various malignancies, including lung adenocarcinoma, breast cancer and chronic lymphocytic leukemia (CLL). There is limited information however on ROR1 in melanoma. In the present study we analysed in seven melanoma cell lines ROR1 expression and phosphorylation as well as the effects of anti-ROR1 monoclonal antibodies (mAbs) and ROR1 suppressing siRNA on cell survival. ROR1 was overexpressed at the protein level to a varying degree and phosphorylated at tyrosine and serine residues. Three of our four self-produced anti-ROR1 mAbs (clones 3H9, 5F1 and 1A8) induced a significant direct apoptosis of the ESTDAB049, ESTDAB112, DFW and A375 cell lines as well as cell death in complement dependent cytotoxicity (CDC) and antibody dependent cellular cytotoxicity (ADCC). The ESTDAB081 and 094 cell lines respectively were resistant to direct apoptosis of the four anti-ROR1 mAbs alone but not in CDC or ADCC. ROR1 siRNA transfection induced downregulation of ROR1 expression both at mRNA and protein levels proceeded by apoptosis of the melanoma cells (ESTDAB049, ESTDAB112, DFW and A375) including ESTDAB081, which was resistant to the direct apoptotic effect of the mAbs. The results indicate that ROR1 may play a role in the survival of melanoma cells. The surface expression of ROR1 on melanoma cells may support the notion that ROR1 might be a suitable target for mAb therapy. PMID:23593420

  9. Inhibition of the receptor tyrosine kinase ROR1 by anti-ROR1 monoclonal antibodies and siRNA induced apoptosis of melanoma cells.

    Directory of Open Access Journals (Sweden)

    Mohammad Hojjat-Farsangi

    Full Text Available The receptor tyrosine kinase (RTK ROR1 is overexpressed and of importance for the survival of various malignancies, including lung adenocarcinoma, breast cancer and chronic lymphocytic leukemia (CLL. There is limited information however on ROR1 in melanoma. In the present study we analysed in seven melanoma cell lines ROR1 expression and phosphorylation as well as the effects of anti-ROR1 monoclonal antibodies (mAbs and ROR1 suppressing siRNA on cell survival. ROR1 was overexpressed at the protein level to a varying degree and phosphorylated at tyrosine and serine residues. Three of our four self-produced anti-ROR1 mAbs (clones 3H9, 5F1 and 1A8 induced a significant direct apoptosis of the ESTDAB049, ESTDAB112, DFW and A375 cell lines as well as cell death in complement dependent cytotoxicity (CDC and antibody dependent cellular cytotoxicity (ADCC. The ESTDAB081 and 094 cell lines respectively were resistant to direct apoptosis of the four anti-ROR1 mAbs alone but not in CDC or ADCC. ROR1 siRNA transfection induced downregulation of ROR1 expression both at mRNA and protein levels proceeded by apoptosis of the melanoma cells (ESTDAB049, ESTDAB112, DFW and A375 including ESTDAB081, which was resistant to the direct apoptotic effect of the mAbs. The results indicate that ROR1 may play a role in the survival of melanoma cells. The surface expression of ROR1 on melanoma cells may support the notion that ROR1 might be a suitable target for mAb therapy.

  10. Lactobacilli expressing variable domain of llama heavy-chain antibody fragments (lactobodies) confer protection against rotavirus-induced diarrhea

    NARCIS (Netherlands)

    Pant, N.; Hultberg, A.; Zhao, Y.; Svensson, L.; Pan-Hammarström, Q.; Johansen, K.; Pouwels, P.H.; Ruggeri, F.M.; Hermans, P.; Frenken, L.; Borén, T.; Marcotte, H.; Hammarström, L.

    2006-01-01

    Background. Rotavirus-induced diarrhea poses a worldwide medical problem in causing substantial morbidity and mortality among children in developing countries. We therefore developed a system for passive immunotherapy in which recombinant lactobacilli constitutively express neutralizing variable

  11. A novel antibody for human induced pluripotent stem cells and embryonic stem cells recognizes a type of keratan sulfate lacking oversulfated structures.

    Science.gov (United States)

    Kawabe, Keiko; Tateyama, Daiki; Toyoda, Hidenao; Kawasaki, Nana; Hashii, Noritaka; Nakao, Hiromi; Matsumoto, Shogo; Nonaka, Motohiro; Matsumura, Hiroko; Hirose, Yoshinori; Morita, Ayaha; Katayama, Madoka; Sakuma, Makoto; Kawasaki, Nobuko; Furue, Miho Kusuda; Kawasaki, Toshisuke

    2013-03-01

    We have generated a monoclonal antibody (R-10G) specific to human induced pluripotent stem (hiPS)/embryonic stem (hES) cells by using hiPS cells (Tic) as an antigen, followed by differential screening of mouse hybridomas with hiPS and human embryonal carcinoma (hEC) cells. Upon western blotting with R-10G, hiPS/ES cell lysates gave a single but an unusually diffuse band at a position corresponding to >250 kDa. The antigen protein was isolated from the induced pluripotent stem (iPS) cell lysates with an affinity column of R-10G. The R-10G positive band was resistant to digestion with peptide N-glycanase F (PNGase F), neuraminidase, fucosidase, chondrotinase ABC and heparinase mix, but it disappeared almost completely on digestion with keratanase, keratanase II and endo-β-galactosidase, indicating that the R-10G epitope is a keratan sulfate. The carrier protein of the R-10G epitope was identified as podocalyxin by liquid chromatography/mass spectrometry (LC/MS/MS) analysis of the R-10G positive-protein band material obtained on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The R-10G epitope is a type of keratan sulfate with some unique properties. (1) The epitope is expressed only on hiPS/ES cells, i.e. not on hEC cells, unlike those recognized by the conventional hiPS/ES marker antibodies. (2) The epitope is a type of keratan sulfate lacking oversulfated structures and is not immunologically cross-reactive with high-sulfated keratan sulfate. (3) The R-10G epitope is distributed heterogeneously on hiPS cells, suggesting that a single colony of undifferentiated hiPS cells consists of different cell subtypes. Thus, R-10G is a novel antibody recognizing hiPS/ES cells, and should be a new molecular probe for disclosing the roles of glycans on these cells.

  12. Effects of Opsonization and Gamma Interferon on Growth of Brucella Melitensis 16M in Mouse Peritoneal Macrophages In Vitro

    Science.gov (United States)

    2000-01-01

    those mediated by cytotoxic T cells, may play more important roles in the control of murine brucellosis . 14. SUBJECT TERMS rjpsonlzatlon, Brucella... brucellosis . Brucella spp., short, nonmotile, nonsporulating, nonencap- sulated, gram-negative aerobic rods, are important facultative intracellular...heated bovine serum induces the produc- tion of oxidative products in bovine neutrophils (6). Although neutrophils represent an important first line

  13. The NTS-DBL2X region of VAR2CSA Induces cross-reactive antibodies that inhibit adhesion of several Plasmodium falciparum isolates to chondroitin sulfate A

    DEFF Research Database (Denmark)

    Bigey, Pascal; Gnidehou, Sédami; Doritchamou, Justin

    2011-01-01

    is difficult. Methods. Using genetic immunization, we raised polyclonal antisera against overlapping segments of VAR2CSA in mice and rabbits. The adhesion-inhibition capacities of induced antisera and of specific antibodies purified from plasma of malaria-exposed pregnant women were assessed on laboratory...

  14. Influence of hirudin and cobra venom factor on the release of 14C-serotonin and 51chromium from human platelets induced by thrombin, collagen, aggregate gammaglobulin and HLA antibody

    International Nuclear Information System (INIS)

    Hagemeyer, G.M.

    1982-01-01

    The present work investigates the influence of hirudin and cobra venom factor on thrombin, collagen, aggregate gammaglobulin and HLA-antibody-induced release of 14 C-serotonin and 51 chromium from human platelets. Besides the platelet-specific release reaction ( 14 C-serotonin) the extent of platelet lysis was determined by measurement of the loss of 51 chromium from the platelets. The results showed the thrombin, collagen and aggregate-gammaglobulin-induced platelet alteration to be a non-complement-dependent reaction of the platelets with release of 14 C-serotonin. Following long-term incubation small quantities of 51 chromium are also released. As this release of 51 chromium cannot be inhibited using cobra venom factor and does not occur in washed platelets either, it is most probably a non-complement-dependent reaction. The HLA-antibody-induced, specific platelet alteration is both complement-dependent and complement-independent. Differentiation is possible by inhibition of the complement-dependent lysis. On the other hand thrombin is of no relevance to the collagen, aggregate gammaglobulin, and HLA-antibody-induced platelet alteration as the interactions of these substances with platelets are not inhibited by hirudin. The above results are confirmed by investigation of the 51 chromium uptake capacity of washed platelets treated previously with thrombin, collagen and HLA antibody. (orig./MG) [de

  15. Salivary antibody levels in adolescents in response to a meningococcal serogroup C conjugate booster vaccination nine years after priming : systemically induced local immunity and saliva as potential surveillance tool

    NARCIS (Netherlands)

    Stoof, Susanne P; van der Klis, Fiona R M; van Rooijen, Debbie M; Bogaert, Debby|info:eu-repo/dai/nl/264105834; Trzcinski, Krzysztof|info:eu-repo/dai/nl/323349609; Sanders, Elisabeth A M|info:eu-repo/dai/nl/126771960; Berbers, Guy A M

    2015-01-01

    BACKGROUND: In several countries large-scale immunization of children and young adults with Meningococcal serogroup C (MenC) conjugate vaccines has induced long-standing herd protection. Salivary antibodies may play an important role in mucosal protection against meningococcal acquisition and

  16. A vaccine of L2 epitope repeats fused with a modified IgG1 Fc induced cross-neutralizing antibodies and protective immunity against divergent human papillomavirus types.

    Directory of Open Access Journals (Sweden)

    Xue Chen

    Full Text Available Current human papillomavirus (HPV major capsid protein L1 virus-like particles (VLPs-based vaccines in clinic induce strong HPV type-specific neutralizing antibody responses. To develop pan-HPV vaccines, here, we show that the fusion protein E3R4 consisting of three repeats of HPV16 L2 aa 17-36 epitope (E3 and a modified human IgG1 Fc scaffold (R4 induces cross-neutralizing antibodies and protective immunity against divergent HPV types. E3R4 was expressed as a secreted protein in baculovirus expression system and could be simply purified by one step Protein A affinity chromatography with the purity above 90%. Vaccination of E3R4 formulated with Freunds adjuvant not only induced cross-neutralizing antibodies against HPV pseudovirus types 16, 18, 45, 52, 58, 6, 11 and 5 in mice, but also protected mice against vaginal challenges with HPV pseudovirus types 16, 45, 52, 58, 11 and 5 for at least eleven months after the first immunization. Moreover, vaccination of E3R4 formulated with FDA approved adjuvant alum plus monophosphoryl lipid A also induced cross-neutralizing antibodies against HPV types 16, 18 and 6 in rabbits. Thus, our results demonstrate that delivery of L2 antigen as a modified Fc-fusion protein may facilitate pan-HPV vaccine development.

  17. Borrelia recurrentis employs a novel multifunctional surface protein with anti-complement, anti-opsonic and invasive potential to escape innate immunity.

    Directory of Open Access Journals (Sweden)

    Sonja Grosskinsky

    Full Text Available Borrelia recurrentis, the etiologic agent of louse-borne relapsing fever in humans, has evolved strategies, including antigenic variation, to evade immune defence, thereby causing severe diseases with high mortality rates. Here we identify for the first time a multifunctional surface lipoprotein of B. recurrentis, termed HcpA, and demonstrate that it binds human complement regulators, Factor H, CFHR-1, and simultaneously, the host protease plasminogen. Cell surface bound factor H was found to retain its activity and to confer resistance to complement attack. Moreover, ectopic expression of HcpA in a B. burgdorferi B313 strain, deficient in Factor H binding proteins, protected the transformed spirochetes from complement-mediated killing. Furthermore, HcpA-bound plasminogen/plasmin endows B. recurrentis with the potential to resist opsonization and to degrade extracellular matrix components. Together, the present study underscores the high virulence potential of B. recurrentis. The elucidation of the molecular basis underlying the versatile strategies of B. recurrentis to escape innate immunity and to persist in human tissues, including the brain, may help to understand the pathological processes underlying louse-borne relapsing fever.

  18. Intragastric administration of attenuated Salmonella typhimurium harbouring transmissible gastroenteritis virus (TGEV) DNA vaccine induced specific antibody production.

    Science.gov (United States)

    Yang, Heng; Cao, Sanjie; Huang, Xiaobo; Liu, Jiawen; Tang, Ying; Wen, Xintian

    2009-08-13

    Attenuated Salmonella typhimurium was selected as a transgenic vehicle for the development of live mucosal vaccines against transmissible gastroenteritis virus (TGEV). A 2.2kb DNA fragment, encoding for N-terminal domain glycoprotein S of TGEV, was amplified by RT-PCR and cloned into eukaryotic expression vector pVAX1. The recombinant plasmid pVAX-S was transformed by electroporation into attenuated S. typhimurium SL7207, the expression and translation of the pVAX-S delivered by recombinant S. typhimurium SL7207 (pVAX-S) was detected in vitro and in vivo respectively. BALB/c mice were inoculated orally with SL7207 (pVAX-S) at different dosages, the bacterium was safe to mice at dosage of 2x10(9)CFU and eventually eliminated from the spleen and liver at week 4 post-immunization. Mice immunized with different dosages of SL7207 (pVAX-S) elicited specific anti-TGEV local mucosal and humoral responses as measured by indirect ELISA assay. Moreover, the immunogenicity of the DNA vaccine was highly dependent on the dosage of the attenuated bacteria used for oral administration, 10(9)CFU dosage group showed higher antibody response than 10(8)CFU and 10(7)CFU dosages groups during week 4-8 post-immunization. The results indicated that attenuated S. typhimurium could be used as a delivery vector for oral immunization of TGEV DNA vaccine.

  19. Passive transfer with serum and IgG antibodies of irradiated cercaria-induced resistance against Schistosoma mansoni in mice

    International Nuclear Information System (INIS)

    Mangold, B.L.; Dean, D.A.

    1986-01-01

    The role of humoral immunity to Schistosoma mansoni infection in C57BL/6J mice was examined by employing a passive transfer system. Sera from highly resistant mice that had been exposed to two or three immunizations with 50-kilorad-gamma-irradiated cercariae were tested for their ability to transfer protection against S. mansoni challenge. All five batches of serum tested were observed to have protective activity. Immune serum recipients exhibited statistically significant reductions in challenge worm burdens of 20 to 50% compared with recipients of normal serum or no serum. The most consistent level of resistance was obtained when immune serum was administered several days post-challenge, i.e., at a time coincident with schistosomulum residence in the lungs. Furthermore, it was shown that the protective activity in immune serum was associated with factors that bind to staphylococcal protein A and that are precipitated by 50% ammonium sulfate; thus it appears that the protective factors in immune serum are IgG antibodies

  20. Dengue Virus Nonstructural Protein 1-Induced Antibodies Cross-React with Human Plasminogen and Enhance Its Activation.

    Science.gov (United States)

    Chuang, Yung-Chun; Lin, Jessica; Lin, Yee-Shin; Wang, Shuying; Yeh, Trai-Ming

    2016-02-01

    Dengue virus (DENV) infection is the most common mosquito-borne viral disease, and it can cause life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Abnormal activation of the coagulation and fibrinolysis system is one of the hallmarks of DHF/DSS. However, the mechanism underlying hemorrhage in DHF/DSS remains elusive. In previous studies, plasminogen (Plg) cross-reactive Abs, which can recognize DENV nonstructural protein (NS) 1, have been found in dengue patients. However, it is unclear whether these Abs are indeed induced by DENV NS1. Thus, we immunized mice with recombinant NS1 from both bacteria and drosophila to determine whether NS1 can induce Plg cross-reactive Abs. The results from the NS1-immunized mouse sera indicated that NS1 immunization induced Abs that could cross-react with Plg. To study the effects of these NS1-induced Plg cross-reactive Abs on fibrinolysis, we isolated several Plg cross-reactive anti-NS1 mAbs from these mice and found that some of them could enhance Plg activation. In addition, epitope mapping with a phage-displayed random peptide library revealed that one of these mAbs (2A5) could recognize NS1 C-terminal residues 305-311, which share sequence homology with Plg residues 590-597. A synthetic peptide of NS1 residues 305-311 could inhibit the binding of both 2A5 and its Fab to Plg and its enhanced activation. Thus, our results suggest that DENV NS1 can induce Plg cross-reactive Abs through molecular mimicry, which can enhance Plg activation and may contribute to the pathogenesis of DHF/DSS. Copyright © 2016 by The American Association of Immunologists, Inc.

  1. Gluten-free vegan diet induces decreased LDL and oxidized LDL levels and raised atheroprotective natural antibodies against phosphorylcholine in patients with rheumatoid arthritis: a randomized study.

    Science.gov (United States)

    Elkan, Ann-Charlotte; Sjöberg, Beatrice; Kolsrud, Björn; Ringertz, Bo; Hafström, Ingiäld; Frostegård, Johan

    2008-01-01

    The purpose of this study was to investigate the effects of vegan diet in patients with rheumatoid arthritis (RA) on blood lipids oxidized low-density lipoprotein (oxLDL) and natural atheroprotective antibodies against phosphorylcholine (anti-PCs). Sixty-six patients with active RA were randomly assigned to either a vegan diet free of gluten (38 patients) or a well-balanced non-vegan diet (28 patients) for 1 year. Thirty patients in the vegan group completed more than 3 months on the diet regimen. Blood lipids were analyzed by routine methods, and oxLDL and anti-PCs were analyzed by enzyme-linked immunosorbent assay. Data and serum samples were obtained at baseline and after 3 and 12 months. Mean ages were 50.0 years for the vegan group and 50.8 years for controls. Gluten-free vegan diet induced lower body mass index (BMI) and low-density lipoprotein (LDL) and higher anti-PC IgM than control diet (p vegan group, BMI, LDL, and cholesterol decreased after both 3 and 12 months (p vegan patients into clinical responders and non-responders at 12 months, the effects on oxLDL and anti-PC IgA were seen only in responders (p vegan diet in RA induces changes that are potentially atheroprotective and anti-inflammatory, including decreased LDL and oxLDL levels and raised anti-PC IgM and IgA levels.

  2. How immunoglobulin G antibodies kill target cells: revisiting an old paradigm.

    Science.gov (United States)

    Biburger, Markus; Lux, Anja; Nimmerjahn, Falk

    2014-01-01

    The capacity of immunoglobulin G (IgG) antibodies to eliminate virtually any target cell has resulted in the widespread introduction of cytotoxic antibodies into the clinic in settings of cancer therapy, autoimmunity, and transplantation, for example. More recently, it has become apparent that also the protection from viral infection via IgG antibodies may require cytotoxic effector functions, suggesting that antibody-dependent cellular cytotoxicity (ADCC) directed against malignant or virally infected cells is one of the most essential effector mechanisms triggered by IgG antibodies to protect the host. A detailed understanding of the underlying molecular and cellular pathways is critical, therefore, to make full use of this antibody effector function. Several studies over the last years have provided novel insights into the effector pathways and innate immune effector cells responsible for ADCC reactions. One of the most notable outcomes of many of these reports is that cells of the mononuclear phagocytic system rather than natural killer cells are critical for removal of IgG opsonized target cells in vivo. © 2014 Elsevier Inc. All rights reserved.

  3. Stringently Defined Otitis Prone Children Demonstrate Deficient Naturally Induced Mucosal Antibody Response toMoraxella catarrhalisProteins.

    Science.gov (United States)

    Ren, Dabin; Murphy, Timothy F; Lafontaine, Eric R; Pichichero, Michael E

    2017-01-01

    Moraxella catarrhalis ( Mcat ) is a prominent mucosal pathogen causing acute otitis media (AOM). We studied Mcat nasopharyngeal (NP) colonization, AOM frequency and mucosal antibody responses to four vaccine candidate Mcat proteins: outer membrane protein (OMP) CD, oligopeptide permease (Opp) A, hemagglutinin (Hag), and Pilin A clade 2 (PilA2) from stringently defined otitis prone (sOP) children, who experience the greatest burden of disease, compared to non-otitis prone (NOP) children. sOP children had higher NP colonization of Mcat (30 vs. 22%, P  = 0.0003) and Mcat -caused AOM rates (49 vs. 24%, P  P  P  = 0.018), Hag (IgG and IgA, both P  P  P  = 0.039) and PilA2 ( P  = 0.0076), and IgA to OMP CD ( P  = 0.010), OppA ( P  = 0.030), and PilA2 ( P  = 0.043) were associated with lower carriage of Mcat in NOP but not sOP children. Higher levels of mucosal IgG to OMP CD ( P  = 0.0070) and Hag ( P  = 0.0003), and IgA to Hag ( P  = 0.0067) at asymptomatic colonization than those at onset of AOM were associated with significantly lower rate of Mcat NP colonization progressing to AOM in NOP compared to sOP children (3 vs. 26%, P  NP colonization and NP colonization progressing to Mcat -caused AOM. Enhancing Mcat antigen-specific mucosal immune responses to levels higher than achieved by natural exposure will be necessary to prevent AOM in sOP children.

  4. Evaluation of an immunoblot methodology for the detection of relevant Entamoeba histolytica antigens by antibodies induced in human amebiasis.

    Science.gov (United States)

    Argüello-García, R; Sánchez-Guillén, M C; Garduño, G; Valadez-Salazar, A; Martínez-García, M C; Muñoz, O; Ortega-Pierres, M G

    1990-01-01

    The complexity of the clinical spectrum in human amebiasis and the high variability in laboratory methods used to detect Entamoeba histolytica infections have impeded the collection and evaluation of reliable epidemiological data. Thus, more sensitive, specific and standardized methods are needed in order to accurately identify infections with this parasite. An important step in the development of serological diagnostic methods is the identification and isolation of specific parasite antigens which are immunogenic in the host. In this work, we have standardized an electroimmunotransfer blot technique to characterize E. histolytica antigens recognized by antibodies present during human amebic infections. An important aspect was an investigation of technical variations in the preparation of cell lysates including the use of different protease inhibitors and solubilizing agents. The highest yield of protein was achieved by homogenization of trophozoites in the presence of 10 mM p-hydroxymercuribenzoate (pHMB) as a protease inhibitor and by lysis using Triton X-100 and a mixture of protease inhibitors. Recovery of degraded vs non-degraded proteins in the cell extracts was evaluated by gradient polyacrylamide gel electrophoresis. Both quantitative and qualitative differences were noted between the different methods of preparing soluble cell extracts. A more complete set of antigenic components was obtained by homogenization and use of pHMB. Thus parasite extracts prepared by this method were selected for protein transfer. In this, the optimal protein concentration was of 120 micrograms of protein per cm of gel width and efficient transfer of proteins to nitrocellulose sheets was achieved at 100 V for 2 hrs and at 4 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Antibodies That Block or Activate Mouse B Cell Activating Factor of the Tumor Necrosis Factor (TNF) Family (BAFF), Respectively, Induce B Cell Depletion or B Cell Hyperplasia.

    Science.gov (United States)

    Kowalczyk-Quintas, Christine; Schuepbach-Mallepell, Sonia; Vigolo, Michele; Willen, Laure; Tardivel, Aubry; Smulski, Cristian R; Zheng, Timothy S; Gommerman, Jennifer; Hess, Henry; Gottenberg, Jacques-Eric; Mackay, Fabienne; Donzé, Olivier; Schneider, Pascal

    2016-09-16

    B cell activating factor of the TNF family (BAFF), also known as B lymphocyte stimulator, is a ligand required for the generation and maintenance of B lymphocytes. In this study, the ability of different monoclonal antibodies to recognize, inhibit, or activate mouse BAFF was investigated. One of them, a mouse IgG1 named Sandy-2, prevented the binding of BAFF to all of its receptors, BAFF receptor, transmembrane activator and calcium modulating ligand interactor, and B cell maturation antigen, at a stoichiometric ratio; blocked the activity of mouse BAFF on a variety of cell-based reporter assays; and antagonized the prosurvival action of BAFF on primary mouse B cells in vitro A single administration of Sandy-2 in mice induced B cell depletion within 2 weeks, down to levels close to those observed in BAFF-deficient mice. This depletion could then be maintained with a chronic treatment. Sandy-2 and a previously described rat IgG1 antibody, 5A8, also formed a pair suitable for the sensitive detection of endogenous circulating BAFF by ELISA or using a homogenous assay. Interestingly, 5A8 and Sandy-5 displayed activities opposite to that of Sandy-2 by stimulating recombinant BAFF in vitro and endogenous BAFF in vivo These tools will prove useful for the detection and functional manipulation of endogenous mouse BAFF and provide an alternative to the widely used BAFF receptor-Fc decoy receptor for the specific depletion of BAFF in mice. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Qualification and application of a surface plasmon resonance-based assay for monitoring potential HAHA responses induced after passive administration of a humanized anti Lewis-Y antibody.

    Science.gov (United States)

    Szolar, O H J; Stranner, S; Zinoecker, I; Mudde, G C; Himmler, G; Waxenecker, G; Nechansky, A

    2006-06-16

    A sensitive, surface plasmon resonance (SPR)-based assay monitoring potential human-anti-human antibody (HAHA) reactions against the monoclonal antibody (mAb) IGN311 is presented. The latter is a fully humanized Lewis-Y carbohydrate specific mAb that is currently tested in a passive immune therapy approach in a clinical phase I trial. For the SPR experiments a BIACORE 3000 analyzer was used. The ligand IGN311 was covalently coupled to the carboxy-methylated dextran matrix of a CM5 research grade chip (BIACORE). In the course of a fully nested experimental design, a four parameter logistic equation was identified as appropriate calibration model ranging from 0.3 microg/mL (lower limit of quantitation, LLOQ) to 200 microg/mL (upper limit of quantitation, ULOQ) using an anti-idiotypic mAb ('HAHA mimic') as calibrator. The bias ranged from -2.4% to 5.5% and the intermediate precision expressed as 95% CI revealed values from 5.6% to 8.3%. Specificity was evaluated using six human serum matrices from healthy donors spiked with calibrator at the limit of quantitation (LOQ) with >80% of values being recovered with less than 25% relative error. The qualified assay was applied to monitor potentially induced HAHA reactivity in 11 patients from a clinical phase I trial with passively administered IGN311. Of the 11 patients, one high HAHA responder and several low responders were identified. Protein-G depletion experiments with human serum samples revealed that the observed response is predominantly caused by IgG binding to the ligand. The characteristics of these HAHA responses were all of the so-called 'Type I' which is defined by a peak response around day 15 that decreases from this point steadily suggesting that some kind of tolerance is established. Therefore, this type of HAHA response is regarded as non critical for the patient's safety.

  7. Involvement of tachykinins and NK1 receptor in the joint inflammation with collagen type II-specific monoclonal antibody-induced arthritis in mice.

    Science.gov (United States)

    Makino, Akira; Sakai, Atsushi; Ito, Hiromoto; Suzuki, Hidenori

    2012-01-01

    Rheumatoid arthritis (RA) is a chronic multisystem disease characterized by persistent joint inflammation associated with severe pain. Because RA is an immune-mediated joint disease and because type II collagen is considered an autoantigen, rodent models of arthritis using collagen type II-specific monoclonal antibodies are valuable for studying the pathogenesis of autoimmune arthritis and for evaluating therapeutic strategies. The tachykinin family peptides, substance P (SP) and hemokinin-1 (HK-1), are expressed in the nervous systems and in many peripheral organs and immunocompetent cells and activate tachykinin NK1 receptors with similar affinities. NK1 receptors are involved in the inflammation and hyperalgesia associated with a variety of inflammatory diseases. In the present study, we examined the involvement of SP and HK-1 in the joint inflammation and hyperalgesia in a collagen antibody-induced arthritis (CAIA) model in mice. The messenger RNA expression levels of the TAC1 gene encoding SP and of the TAC4 gene encoding HK-1 were decreased in the dorsal root ganglia and spinal cord at the peak of the inflammatory symptoms in CAIA. Systemic injection of an NK1 receptor antagonist, WIN 51708, significantly inhibited the joint swelling, but not the mechanical allodynia, on day 7 in CAIA mice. The messenger RNA expression levels of TAC1 and TAC4 in the dorsal root ganglia and dorsal spinal cord were unaffected by treatment with WIN 51708. These findings suggest that tachykinins and NK1 receptors play a key role in joint inflammation, rather than in nociceptive sensitization, in CAIA.

  8. Multi-response model for rheumatoid arthritis based on delay differential equations in collagen-induced arthritic mice treated with an anti-GM-CSF antibody.

    Science.gov (United States)

    Koch, Gilbert; Wagner, Thomas; Plater-Zyberk, Christine; Lahu, Gezim; Schropp, Johannes

    2012-02-01

    Collagen-induced arthritis (CIA) in mice is an experimental model for rheumatoid arthritis, a human chronic inflammatory destructive disease. The therapeutic effect of neutralizing the cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) by an antibody was examined in the mouse disease in a view of deriving a pharmacokinetic/pharmacodynamic (PKPD) model. In CIA mice the development of disease is measured by a total arthritic score (TAS) and an ankylosis score (AKS). We present a multi-response PKPD model which describes the time course of the unperturbed and perturbed TAS and AKS. The antibody acts directly on GM-CSF by binding to it. Therefore, a compartment for the cytokine GM-CSF is an essential component of the mathematical model. This compartment drives the disease development in the PKPD model. Different known properties of arthritis development in the CIA model are included in the PKPD model. Firstly, the inflammation, driven by GM-CSF, dominates at the beginning of the disease and decreases after some time. Secondly, a destructive (ankylosis) part evolves in the TAS that is delayed in time. In order to model these two properties a delay differential equation was used. The PKPD model was applied to different experiments with doses ranging from 0.1 to 100 mg/kg. The influence of the drug was modeled by a non-linear approach. The final mathematical model consists of three differential equations representing the compartments for GM-CSF, inflammation and destruction. Our mathematical model described well all available dosing schedules by a simultaneous fit. We also present an equivalent and easy reformulation as ordinary differential equation which grants the use of standard PKPD software.

  9. Caprylic acid-induced impurity precipitation from protein A capture column elution pool to enable a two-chromatography-step process for monoclonal antibody purification.

    Science.gov (United States)

    Zheng, Ji; Wang, Lu; Twarowska, Barbara; Laino, Sarah; Sparks, Colleen; Smith, Timothy; Russell, Reb; Wang, Michelle

    2015-01-01

    This article presents the use of caprylic acid (CA) to precipitate impurities from the protein A capture column elution pool for the purification of monoclonal antibodies (mAbs) with the objective of developing a two chromatography step antibody purification process. A CA-induced impurity precipitation in the protein A column elution pool was evaluated as an alternative method to polishing chromatography techniques for use in the purification of mAbs. Parameters including pH, CA concentrations, mixing time, mAb concentrations, buffer systems, and incubation temperatures were evaluated on their impacts on the impurity removal, high-molecular weight (HMW) formation and precipitation step yield. Both pH and CA concentration, but not mAb concentrations and buffer systems, are key parameters that can affect host-cell proteins (HCPs) clearance, HMW species, and yield. CA precipitation removes HCPs and some HMW species to the acceptable levels under the optimal conditions. The CA precipitation process is robust at 15-25°C. For all five mAbs tested in this study, the optimal CA concentration range is 0.5-1.0%, while the pH range is from 5.0 to 6.0. A purification process using two chromatography steps (protein A capture column and ion exchange polishing column) in combination with CA-based impurity precipitation step can be used as a robust downstream process for mAb molecules with a broad range of isoelectric points. Residual CA can be effectively removed by the subsequent polishing cation exchange chromatography. © 2015 American Institute of Chemical Engineers.

  10. [Antibody induction after intrauterine interventions].

    Science.gov (United States)

    Hoch, J; Giers, G; Bald, R; Hansmann, M; Hanfland, P

    1993-06-01

    Immunohematologic and clinical data, i.e., antibody profile, location of the placenta, mode of cordocentesis, obtained from 48 pregnant patients with irregular erythrocyte antibodies during the last 2 years have been retrospectively evaluated. All fetuses of the patients received intrauterine transfusions for the treatment of fetal erythroblastosis. In 16 (33%) patients (group I) a secondarily induced antibody was detected after the onset of intrauterine transfusion therapy. 32 (67%) patients (group II) did not further develop new antibody specificities. Group I exhibited a significantly different distribution in the location of the placenta (p pregnant women. In group I a 5-fold higher rate of anterior than posterior placenta location was found. The mode of cordocentesis differed significantly (p antibodies by invasive intrauterine interventions in our patients depended indirectly on the location of the placenta and directly on the mode of the puncture (trans- vs. paraplacental access).

  11. "Auto-anti-IgE": naturally occurring IgG anti-IgE antibodies may inhibit allergen-induced basophil activation.

    Science.gov (United States)

    Chan, Yih-Chih; Ramadani, Faruk; Santos, Alexandra F; Pillai, Prathap; Ohm-Laursen, Line; Harper, Clare E; Fang, Cailong; Dodev, Tihomir S; Wu, Shih-Ying; Ying, Sun; Corrigan, Christopher J; Gould, Hannah J

    2014-12-01

    Naturally occurring IgE-specific IgG autoantibodies have been identified in patients with asthma and other diseases, but their spectrum of functions is poorly understood. Address the hypothesis that: (i) IgG anti-IgE autoantibodies are detectable in the serum of all subjects but elevated in asthmatic patients regardless of atopic status as compared with controls; (ii) some activate IgE-sensitized basophils; and (iii) some inhibit allergen-induced basophil activation. IgE-specific IgG autoantibodies were detected and quantified in sera using ELISA. Sera were examined for their ability to activate IgE-sensitized human blood basophils in the presence and absence of allergen using a basophil activation test, and to inhibit allergen binding to specific IgE on a rat basophilic cell line stably expressing human FcεRI. IgG autoantibodies binding to both free and FcεRI-bound IgE were detected in patients with atopic and non-atopic asthma, as well as controls. While some were able to activate IgE-sensitised basophils, others inhibited allergen-induced basophil activation, at least partly by inhibiting binding of IgE to specific allergen. Naturally occurring IgG anti-IgE autoantibodies may inhibit, as well as induce, basophil activation. They act in a manner distinct from therapeutic IgG anti-IgE antibodies such as omalizumab. They may at least partly explain why atopic subjects who make allergen-specific IgE never develop clinical symptoms, and why omalizumab therapy is of variable clinical benefit in severe atopic asthma. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Recombinant monovalent llama-derived antibody fragments (VHH to rotavirus VP6 protect neonatal gnotobiotic piglets against human rotavirus-induced diarrhea.

    Directory of Open Access Journals (Sweden)

    Celina G Vega

    Full Text Available Group A Rotavirus (RVA is the leading cause of severe diarrhea in children. The aims of the present study were to determine the neutralizing activity of VP6-specific llama-derived single domain nanoantibodies (VHH nanoAbs against different RVA strains in vitro and to evaluate the ability of G6P[1] VP6-specific llama-derived single domain nanoantibodies (VHH to protect against human rotavirus in gnotobiotic (Gn piglets experimentally inoculated with virulent Wa G1P[8] rotavirus. Supplementation of the daily milk diet with 3B2 VHH clone produced using a baculovirus vector expression system (final ELISA antibody -Ab- titer of 4096; virus neutralization -VN- titer of 256 for 9 days conferred full protection against rotavirus associated diarrhea and significantly reduced virus shedding. The administration of comparable levels of porcine IgG Abs only protected 4 out of 6 of the animals from human RVA diarrhea but significantly reduced virus shedding. In contrast, G6P[1]-VP6 rotavirus-specific IgY Abs purified from eggs of hyperimmunized hens failed to protect piglets against human RVA-induced diarrhea or virus shedding when administering similar quantities of Abs. The oral administration of VHH nanoAb neither interfered with the host's isotype profiles of the Ab secreting cell responses to rotavirus, nor induced detectable host Ab responses to the treatment in serum or intestinal contents. This study shows that the oral administration of rotavirus VP6-VHH nanoAb is a broadly reactive and effective treatment against rotavirus-induced diarrhea in neonatal pigs. Our findings highlight the potential value of a broad neutralizing VP6-specific VHH nanoAb as a treatment that can complement or be used as an alternative to the current strain-specific RVA vaccines. Nanobodies could also be scaled-up to develop pediatric medication or functional food like infant milk formulas that might help treat RVA diarrhea.

  13. Recombinant monovalent llama-derived antibody fragments (VHH) to rotavirus VP6 protect neonatal gnotobiotic piglets against human rotavirus-induced diarrhea.

    Science.gov (United States)

    Vega, Celina G; Bok, Marina; Vlasova, Anastasia N; Chattha, Kuldeep S; Gómez-Sebastián, Silvia; Nuñez, Carmen; Alvarado, Carmen; Lasa, Rodrigo; Escribano, José M; Garaicoechea, Lorena L; Fernandez, Fernando; Bok, Karin; Wigdorovitz, Andrés; Saif, Linda J; Parreño, Viviana

    2013-01-01

    Group A Rotavirus (RVA) is the leading cause of severe diarrhea in children. The aims of the present study were to determine the neutralizing activity of VP6-specific llama-derived single domain nanoantibodies (VHH nanoAbs) against different RVA strains in vitro and to evaluate the ability of G6P[1] VP6-specific llama-derived single domain nanoantibodies (VHH) to protect against human rotavirus in gnotobiotic (Gn) piglets experimentally inoculated with virulent Wa G1P[8] rotavirus. Supplementation of the daily milk diet with 3B2 VHH clone produced using a baculovirus vector expression system (final ELISA antibody -Ab- titer of 4096; virus neutralization -VN- titer of 256) for 9 days conferred full protection against rotavirus associated diarrhea and significantly reduced virus shedding. The administration of comparable levels of porcine IgG Abs only protected 4 out of 6 of the animals from human RVA diarrhea but significantly reduced virus shedding. In contrast, G6P[1]-VP6 rotavirus-specific IgY Abs purified from eggs of hyperimmunized hens failed to protect piglets against human RVA-induced diarrhea or virus shedding when administering similar quantities of Abs. The oral administration of VHH nanoAb neither interfered with the host's isotype profiles of the Ab secreting cell responses to rotavirus, nor induced detectable host Ab responses to the treatment in serum or intestinal contents. This study shows that the oral administration of rotavirus VP6-VHH nanoAb is a broadly reactive and effective treatment against rotavirus-induced diarrhea in neonatal pigs. Our findings highlight the potential value of a broad neutralizing VP6-specific VHH nanoAb as a treatment that can complement or be used as an alternative to the current strain-specific RVA vaccines. Nanobodies could also be scaled-up to develop pediatric medication or functional food like infant milk formulas that might help treat RVA diarrhea.

  14. Nuclear localization of CD26 induced by a humanized monoclonal antibody inhibits tumor cell growth by modulating of POLR2A transcription.

    Directory of Open Access Journals (Sweden)

    Kohji Yamada

    Full Text Available CD26 is a type II glycoprotein known as dipeptidyl peptidase IV and has been identified as one of the cell surface markers associated with various types of cancers and a subset of cancer stem cells. Recent studies have suggested that CD26 expression is involved in tumor growth, tumor invasion, and metastasis. The CD26 is shown in an extensive intracellular distribution, ranging from the cell surface to the nucleus. We have previously showed that the humanized anti-CD26 monoclonal antibody (mAb, YS110, exhibits inhibitory effects on various cancers. However, functions of CD26 on cancer cells and molecular mechanisms of impaired tumor growth by YS110 treatment are not well understood. In this study, we demonstrated that the treatment with YS110 induced nuclear translocation of both cell-surface CD26 and YS110 in cancer cells and xenografted tumor. It was shown that the CD26 and YS110 were co-localized in nucleus by immunoelectron microscopic analysis. In response to YS110 treatment, CD26 was translocated into the nucleus via caveolin-dependent endocytosis. It was revealed that the nuclear CD26 interacted with a genomic flanking region of the gene for POLR2A, a subunit of RNA polymerase II, using a chromatin immunoprecipitation assay. This interaction with nuclear CD26 and POLR2A gene consequently led to transcriptional repression of the POLR2A gene, resulting in retarded cell proliferation of cancer cells. Furthermore, the impaired nuclear transport of CD26 by treatment with an endocytosis inhibitor or expressions of deletion mutants of CD26 reversed the POLR2A repression induced by YS110 treatment. These findings reveal that the nuclear CD26 functions in the regulation of gene expression and tumor growth, and provide a novel mechanism of mAb-therapy related to inducible translocation of cell-surface target molecule into the nucleus.

  15. Incidence of radiation-induced Graves' disease in patients treated with radioiodine for thyroid autonomy before and after introduction of a high-sensitivity TSH receptor antibody assay

    International Nuclear Information System (INIS)

    Dunkelmann, Simone; Wolf, Ricarda; Koch, Annedore; Kittner, Christian; Groth, Peter; Schuemichen, Carl

    2004-01-01

    Autoimmune hyperthyroidism may occur several months after radioiodine therapy (RIT) for functional thyroid autonomy. Exacerbation of pre-existing subclinical Graves' disease (GD) has been held responsible for this phenomenon. Determination of TSH receptor antibody using solubilised porcine epithelial cell membranes is insensitive and may have failed to diagnose GD in these patients before RIT. Following the introduction of a more sensitive assay, using the human TSH receptor as an antigen, it has been expected that the incidence of radiation-induced GD after RIT for functional thyroid autonomy will be reduced. In a first group of 1,428 patients treated between November 1993 and March 1997 (group I) we used the porcine TRAb assay to exclude GD, while in a second group comprising 1,408 patients treated between January 2000 and December 2001 (group II), GD was excluded using the human TRAb assay. A matched control group of 231 patients was derived from group II. In group I a total of 15 (1.05%) patients developed obvious or suspected radiation-induced GD, while in group II 17 (1.2%) did so; the interval until development of GD was 8.4 and 8.8 months, respectively, after RIT. Serum anti-thyroid peroxidase levels before RIT were elevated in 36.4% of group I patients and 47.1% of group II patients, but in only 5.6% of the control group. Other non-specific signs of mild immunopathy of the thyroid were seen retrospectively in 73.3%, 64.7% and 16.0% of the patients in these three groups, respectively. In conclusion, the introduction of a high-sensitivity TRAb assay did not reduce the incidence of autoimmune hyperthyroidism occurring late after RIT for functional thyroid autonomy, but mild immunopathy of the thyroid is seen more frequently in these patients and seems to be a predisposing factor in the development of radiation-induced GD. (orig.)

  16. Antibody biotechnology

    African Journals Online (AJOL)

    STORAGESEVER

    2009-07-06

    Jul 6, 2009 ... and automated, the hybrid cells can be stored for many years in liquid nitrogen and antibodies production is homogeneous. The hybridoma method .... they may be modified to vehicle active molecules such as radio-isotopes, toxins, cytokines, enzyme etc. In these cases, the therapeutic effect is due to ...

  17. Catalytic Antibodies

    Indian Academy of Sciences (India)

    The ability of the highly evolved machinery of immune system to produce structurally and functionally complex ... to Pauling, if the structure of the antigen binding site of antibodies were to be produced in a random ..... where the immune system of the body is destructive, as in autoimmune disorders or after organ transplant.

  18. Catalytic Antibodies

    Indian Academy of Sciences (India)

    While chemistry provides the framework for understanding the structure and function of biomolecules, the immune sys- tem provides a highly evolved natural process to generate one class of complex biomolecules – the antibodies. A combination of the two could be exploited to generate new classes of molecules with novel ...

  19. Anti-idiotypic antibodies to poliovirus antibodies in commercial immunoglubulin preparations, human serum and milk.

    NARCIS (Netherlands)

    M. Hahn-Zoric; B. Carlsson; S. Jeansson; H.P. Ekre; A.D.M.E. Osterhaus (Albert); D. Roberton; L.A. Hanson

    1993-01-01

    textabstractOur previous studies have suggested that fetal antibody production can be induced by maternal antiidiotypic antibodies transferred to the fetus via the placenta. We tested commercial Ig, sera, and milk for the presence of anti-idiotypic antibodies to poliovirus type 1, using affinity

  20. A putative amino acid ABC transporter substrate-binding protein, NMB1612, from Neisseria meningitidis, induces murine bactericidal antibodies against meningococci expressing heterologous NMB1612 proteins.

    Science.gov (United States)

    Hung, Miao-Chiu; Humbert, María Victoria; Laver, Jay R; Phillips, Renee; Heckels, John E; Christodoulides, Myron

    2015-08-26

    The nmb1612 (NEIS1533) gene encoding the ~27-kDa putative amino acid ATP-binding cassette (ABC) transporter, periplasmic substrate-binding protein from Neisseria meningitidis serogroup B (MenB) strain MC58 was cloned and expressed in Escherichia coli, and the purified recombinant (r)NMB1612 was used for animal immunization studies. Immunization of mice with rNMB1612 adsorbed to Al(OH)3 and in liposomes with and without MPLA, induced antiserum with bactericidal activity in an assay using baby rabbit complement, against the homologous strain MC58 (encoding protein representative of Allele 62) and killed heterologous strains encoding proteins of three other alleles (representative of Alleles 1, 64 and 68), with similar SBA titres. However, strain MC58 was not killed (titre bactericidal assay (hSBA) using anti-rNMB1612 sera, although another strain (MC168) expressing the same protein was killed (median titres of 16-64 in the hSBA). Analysis of the NMB1612 amino acid sequences from 4351 meningococcal strains in the pubmlst.org/Neisseria database and a collection of 13 isolates from colonized individuals and from patients, showed that antibodies raised against rNMB1612 could potentially kill at least 72% of the MenB strains in the complete sequence database. For MenB disease occurring specifically in the UK from 2013 to 2015, >91% of the isolates causing disease in this recent period expressed NMB1612 protein encoded by Allele 1 and could be potentially killed by sera raised to the recombinant antigen in the current study. The NMB1612 protein was surface-accessible and expressed by different meningococcal strains. In summary, the properties of (i) NMB1612 protein conservation and expression, (ii) limited amino acid sequence variation between proteins encoded by different alleles, and (iii) the ability of a recombinant protein to induce cross-strain bactericidal antibodies, would all suggest a promising antigen for consideration for inclusion in new meningococcal vaccines

  1. Egg yolk IgY: protection against rotavirus induced diarrhea and modulatory effect on the systemic and mucosal antibody responses in newborn calves.

    Science.gov (United States)

    Vega, C; Bok, M; Chacana, P; Saif, L; Fernandez, F; Parreño, V

    2011-08-15

    Bovine rotavirus (BRV) is an important cause of diarrhea in newborn calves. Local passive immunity is the most efficient protective strategy to control the disease. IgY technology (the use of chicken egg yolk immunoglobulins) is an economic and practical alternative to prevent BRV diarrhea in dairy calves. The aim of this study was to evaluate the protection and immunomodulation induced by the oral administration of egg yolk enriched in BRV specific IgY to experimentally BRV infected calves. All calves in groups Gp 1, 2 and 3 received control colostrum (CC; BRV virus neutralization Ab titer - VN=65,536; ELISA BRV IgG(1)=16,384) prior to gut closure. After gut closure, calves received milk supplemented with 6% BRV-immune egg yolk [(Gp 1) VN=2048; ELISA IgY Ab titer=4096] or non-immune control egg yolk [(Gp 2) VNcontrols (Gp 3 and 4, respectively). Calves were inoculated with 10(5.85)focus forming units (FFU) of virulent BRV IND at 2 days of age. Control calves (Gp 3 and 4) and calves fed control IgY (Gp 2) were infected and developed severe diarrhea. Around 80% calves in Gp 1 (IgY 4096) were infected, but they showed 80% (4/5) protection against BRV diarrhea. Bovine RV-specific IgY Ab were detected in the feces of calves in Gp 1, indicating that avian antibodies (Abs) remained intact after passage through the gastrointestinal tract. At post infection day 21, the duodenum was the major site of BRV specific antibody secreting cells (ASC) in all experimental groups. Mucosal ASC responses of all isotypes were significantly higher in the IgY treated groups, independently of the specificity of the treatment, indicating that egg yolk components modulated the immune response against BRV infection at the mucosal level. These results indicate that supplementing newborn calves' diets for the first 14 days of life with egg yolk enriched in BRV-specific IgY represents a promising strategy to prevent BRV diarrhea. Moreover a strong active ASC immune response is induced in the

  2. TLR9 ligand (CpG oligodeoxynucleotide induces CLL B-cells to differentiate into CD20+ antibody-secreting cells

    Directory of Open Access Journals (Sweden)

    Hussein eGhamlouch

    2014-06-01

    Full Text Available B-cell chronic lymphocytic leukemia (CLL is the most frequent adult leukemia in the Western world. It is a heterogeneous disease characterized by clonal proliferation and the accumulation of CD5+ mature B lymphocytes. However, the normal counterpart from which the latter cells arise has not yet been identified. CD27 expression and gene expression profiling data suggest that CLL cells are related to memory B-cells. In vitro, memory B-cells differentiate into plasma cells when stimulated with CpG oligodeoxynucleotide (CpG. The objective of the present study was therefore to investigate the ability of CpG, in the context of CD40 ligation, to induce the differentiation of CLL B-cells into antibody-secreting cells (ASCs. CD20+CD38− CLL B-cells were stimulated with a combination of CpG, CD40 ligand and cytokines (CpG/CD40L/c in a two-step, seven-day culture system. We found that the CpG/CD40L/c culture system prompted CLL B-cells to differentiate into CD19+CD20+CD27+CD38- ASCs. These cells secreted large amounts of IgM and had the same shape as plasma cells. However, only IgMs secreted by ASCs that had differentiated from unmutated CLL B-cells were poly/autoreactive. Class-switch recombination to IgG and IgA was detected in cells expressing the activation-induced cytidine deaminase gene (AICDA. Although these ASCs expressed high levels of the transcription factors PRDM1 (BLIMP1, IRF4 and XBP1s, they did not downregulate expression of PAX5. Our results suggest that CLL B-cells can differentiate into ASCs, undergo class-switch recombination and produce poly/autoreactive antibodies. Furthermore, our findings may be relevant for (i identifying the normal counterpart of CLL B-cells and (ii developing novel treatment strategies in CLL.

  3. Salmonella Typhimurium induces SPI-1 and SPI-2 regulated and strain dependent downregulation of MHC II expression on porcine alveolar macrophages

    Directory of Open Access Journals (Sweden)

    Van Parys Alexander

    2012-06-01

    Full Text Available Abstract Foodborne salmonellosis is one of the most important bacterial zoonotic diseases worldwide. Salmonella Typhimurium is the serovar most frequently isolated from persistently infected slaughter pigs in Europe. Circumvention of the host’s immune system by Salmonella might contribute to persistent infection of pigs. In the present study, we found that Salmonella Typhimurium strain 112910a specifically downregulated MHC II, but not MHC I, expression on porcine alveolar macrophages in a Salmonella pathogenicity island (SPI-1 and SPI-2 dependent way. Salmonella induced downregulation of MHC II expression and intracellular proliferation of Salmonella in macrophages were significantly impaired after opsonization with Salmonella specific antibodies prior to inoculation. Furthermore, the capacity to downregulate MHC II expression on macrophages differed significantly among Salmonella strains, independently of strain specific differences in invasion capacity, Salmonella induced cytotoxicity and altered macrophage activation status. The fact that strain specific differences in MHC II downregulation did not correlate with the extent of in vitro SPI-1 or SPI-2 gene expression indicates that other factors are involved in MHC II downregulation as well. Since Salmonella strain dependent interference with the pig’s immune response through downregulation of MHC II expression might indicate that certain Salmonella strains are more likely to escape serological detection, our findings are of major interest for Salmonella monitoring programs primarily based on serology.

  4. Anti-M Antibody Induced Prolonged Anemia Following Hemolytic Disease of the Newborn Due to Erythropoietic Suppression in 2 Siblings.

    Science.gov (United States)

    Ishida, Atsushi; Ohto, Hitoshi; Yasuda, Hiroyasu; Negishi, Yutaka; Tsuiki, Hideki; Arakawa, Takeshi; Yagi, Yoshihito; Uchimura, Daisuke; Miyazaki, Toru; Ohashi, Wataru; Takamoto, Shigeru

    2015-08-01

    Hemolytic disease of the newborn (HDN) arising from MNSs incompatibility is rare, with few reports of prolonged anemia and reticulocytopenia following HDN. We report the younger of 2 male siblings, both of whom had anti-M-induced HDN and anemia persisting for over a month. Peripheral reticulocytes remained inappropriately low for the degree of anemia, and they needed multiple red cell transfusions. Viral infections were ruled out. Corticosteroids were given for suspected pure red cell aplasia. Anemia and reticulocytopenia subsequently improved. Colony-forming unit erythroid assay revealed erythropoietic suppression of M antigen-positive erythroid precursor cells cultured with maternal or infant sera containing anti-M. In conclusion, maternal anti-M caused HDN and prolonged anemia by erythropoietic suppression in 2 siblings.

  5. Anti-osteopontin monoclonal antibody prevents ovariectomy-induced osteoporosis in mice by promotion of osteoclast apoptosis

    International Nuclear Information System (INIS)

    Zhang, Bo; Dai, Jianxin; Wang, Huaqing; Wei, Huafeng; Zhao, Jian; Guo, Yajun

    2014-01-01

    Highlight: • We first report that anti-osteopontin mAb could protect osteoporosis in mice. • Anti-osteopontin mAb could promote the osteoclast apoptosis. • Targeting osteopontin might have therapeutic potentials for osteoporosis. - Abstract: Osteopontin (OPN) is abundant in mineralized tissues and has long been implicated in bone remodeling. However, the therapeutic effect of targeting OPN in bone loss diseases and the underlying molecular mechanism remain largely unknown. Here, we reported that anti-OPN mAb (23C3) could protect against ovariectomy-induced osteoporosis in mice, demonstrated by microcomputed tomography analysis and histopathology evaluation. In vitro assay showed that 23C3 mAb reduced osteoclasts (OCs)-mediated bone resorption through promotion of mature OC apoptosis. Thus, the study has important implications for understanding the role of OPN in OC bone resorption and survival, and OPN antagonists may have therapeutic potential for osteoporosis and other osteopenic diseases

  6. Flow-Induced Dispersion Analysis for Probing Anti-dsDNA Antibody Binding Heterogeneity in Systemic Lupus Erythematosus Patients

    DEFF Research Database (Denmark)

    Poulsen, Nicklas N; Pedersen, Morten E; Østergaard, Jesper

    2016-01-01

    , specificity, and accuracy with established assays. Also, existing methodologies for quantification of autoantibodies are challenging to transfer to a point-of-care setting. Here we present the use of flow-induced dispersion analysis (FIDA) for rapid (minutes) measurement of autoantibodies against ds......DNA. The assay is based on Taylor dispersion analysis (TDA) and is fully automated with the use of standard capillary electrophoresis (CE) based equipment employing fluorescence detection. It is robust toward matrix effects as demonstrated by the direct analysis of samples composed of up to 85% plasma derived...... from human blood samples, and it allows for flexible exchange of the DNA sequences used to probe for the autoantibodies. Plasma samples from SLE positive patients were analyzed using the new FIDA methodology as well as by standard indirect immunofluorescence and solid-phase immunoassays. Interestingly...

  7. Anti-osteopontin monoclonal antibody prevents ovariectomy-induced osteoporosis in mice by promotion of osteoclast apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Bo [International Joint Cancer Institute, The Second Military Medical University, 800 Xiang Yin Road, Shanghai 200433 (China); PLA General Hospital Cancer Center and PLA Cancer Research Institute, PLA Postgraduate School of Medicine, 28 Fuxing Road, Beijing (China); Dai, Jianxin [International Joint Cancer Institute, The Second Military Medical University, 800 Xiang Yin Road, Shanghai 200433 (China); PLA General Hospital Cancer Center and PLA Cancer Research Institute, PLA Postgraduate School of Medicine, 28 Fuxing Road, Beijing (China); National Engineering Research Center for Antibody Medicine and Shanghai Key Lab. of Cell Engineering and Antibody, 399 Libing Road, Shanghai 201203 (China); Wang, Huaqing [International Joint Cancer Institute, The Second Military Medical University, 800 Xiang Yin Road, Shanghai 200433 (China); Wei, Huafeng [International Joint Cancer Institute, The Second Military Medical University, 800 Xiang Yin Road, Shanghai 200433 (China); PLA General Hospital Cancer Center and PLA Cancer Research Institute, PLA Postgraduate School of Medicine, 28 Fuxing Road, Beijing (China); Zhao, Jian [International Joint Cancer Institute, The Second Military Medical University, 800 Xiang Yin Road, Shanghai 200433 (China); National Engineering Research Center for Antibody Medicine and Shanghai Key Lab. of Cell Engineering and Antibody, 399 Libing Road, Shanghai 201203 (China); Guo, Yajun, E-mail: yguo_smmu@163.com [International Joint Cancer Institute, The Second Military Medical University, 800 Xiang Yin Road, Shanghai 200433 (China); PLA General Hospital Cancer Center and PLA Cancer Research Institute, PLA Postgraduate School of Medicine, 28 Fuxing Road, Beijing (China); National Engineering Research Center for Antibody Medicine and Shanghai Key Lab. of Cell Engineering and Antibody, 399 Libing Road, Shanghai 201203 (China); and others

    2014-09-26

    Highlight: • We first report that anti-osteopontin mAb could protect osteoporosis in mice. • Anti-osteopontin mAb could promote the osteoclast apoptosis. • Targeting osteopontin might have therapeutic potentials for osteoporosis. - Abstract: Osteopontin (OPN) is abundant in mineralized tissues and has long been implicated in bone remodeling. However, the therapeutic effect of targeting OPN in bone loss diseases and the underlying molecular mechanism remain largely unknown. Here, we reported that anti-OPN mAb (23C3) could protect against ovariectomy-induced osteoporosis in mice, demonstrated by microcomputed tomography analysis and histopathology evaluation. In vitro assay showed that 23C3 mAb reduced osteoclasts (OCs)-mediated bone resorption through promotion of mature OC apoptosis. Thus, the study has important implications for understanding the role of OPN in OC bone resorption and survival, and OPN antagonists may have therapeutic potential for osteoporosis and other osteopenic diseases.

  8. Human anti-Dectin-1 antibody, hybridoma producing said antibody and applications thereof

    OpenAIRE

    Kremer, Leonor; Llorente Gómez, María de las Mercedes; Casasnovas, José María; Fernández Ruíz, Elena; Galán Díez, Marta

    2008-01-01

    [EN] The invention relates to hybridoma MGD3 and the monoclonal antibody produced thereby (also called MGD3), which specifically recognises the human Dectin-1 membrane receptor. Antibody MGD3 is capable of inhibiting the binding of Dectin-1 to the natural ligand thereof, the ss-glucans that are components of the fungal wall. In addition, the aforementioned antibody specifically blocks binding to Candida albicans and the secretion of cytokines induced thereby. The MGD3 antibody obtained enable...

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

    Directory of Open Access Journals (Sweden)

    Staffan Görander

    2014-11-01

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

  10. Anti-glycoprotein g antibodies of herpes simplex virus 2 contribute to complete protection after vaccination in mice and induce antibody-dependent cellular cytotoxicity and complement-mediated cytolysis.

    Science.gov (United States)

    Görander, Staffan; Ekblad, Maria; Bergström, Tomas; Liljeqvist, Jan-Åke

    2014-11-12

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

  11. Motavizumab, A Neutralizing Anti-Respiratory Syncytial Virus (Rsv Monoclonal Antibody Significantly Modifies The Local And Systemic Cytokine Responses Induced By Rsv In The Mouse Model

    Directory of Open Access Journals (Sweden)

    Jafri Hasan S

    2007-10-01

    Full Text Available Abstract Motavizumab (MEDI-524 is a monoclonal antibody with enhanced neutralizing activity against RSV. In mice, motavizumab suppressed RSV replication which resulted in significant reduction of clinical parameters of disease severity. We evaluated the effect of motavizumab on the local and systemic immune response induced by RSV in the mouse model. Balb/c mice were intranasally inoculated with 106.5 PFU RSV A2 or medium. Motavizumab was given once intraperitoneally (1.25 mg/mouse as prophylaxis, 24 h before virus inoculation. Bronchoalveolar lavage (BAL and serum samples were obtained at days 1, 5 (acute and 28 (long-term post inoculation and analyzed with a multiplex assay (Beadlyte Upstate, NY for simultaneous quantitation of 18 cytokines: IL-1α, IL-1β, IL-2, IL-3, IL-4, IL-5, IL-6, KC (similar to human IL-8, IL-10, IL-12p40, IL-12p70, IL-13, IL-17, TNF-α, MCP-1, RANTES, IFN-γ and GM-CSF. Overall, cytokine concentrations were lower in serum than in BAL samples. By day 28, only KC was detected in BAL specimens at low concentrations in all groups. Administration of motavizumab significantly reduced (p

  12. Vaccine-induced Human Antibodies Specific for the Third Variable Region of HIV-1 gp120 Impose Immune Pressure on Infecting Viruses

    Directory of Open Access Journals (Sweden)

    Susan Zolla-Pazner

    2014-11-01

    Full Text Available To evaluate the role of V3-specific IgG antibodies (Abs in the RV144 clinical HIV vaccine trial, which reduced HIV-1 infection by 31.2%, the anti-V3 Ab response was assessed. Vaccinees' V3 Abs were highly cross-reactive with cyclic V3 peptides (cV3s from diverse virus subtypes. Sieve analysis of CRF01_AE breakthrough viruses from 43 vaccine- and 66 placebo-recipients demonstrated an estimated vaccine efficacy of 85% against viruses with amino acids mismatching the vaccine at V3 site 317 (p = 0.004 and 52% against viruses matching the vaccine at V3 site 307 (p = 0.004. This analysis was supported by data showing that vaccinees' plasma Abs were less reactive with I307 when replaced with residues found more often in vaccinees' breakthrough viruses. Simultaneously, viruses with mutations at F317 were less infectious, possibly due to the contribution of F317 to optimal formation of the V3 hydrophobic core. These data suggest that RV144-induced V3-specific Abs imposed immune pressure on infecting viruses and inform efforts to design an HIV vaccine.

  13. An amino-terminal segment of hantavirus nucleocapsid protein presented on hepatitis B virus core particles induces a strong and highly cross-reactive antibody response in mice

    International Nuclear Information System (INIS)

    Geldmacher, Astrid; Skrastina, Dace; Petrovskis, Ivars; Borisova, Galina; Berriman, John A.; Roseman, Alan M.; Crowther, R. Anthony; Fischer, Jan; Musema, Shamil; Gelderblom, Hans R.; Lundkvist, Aake; Renhofa, Regina; Ose, Velta; Krueger, Detlev H.; Pumpens, Paul; Ulrich, Rainer

    2004-01-01

    Previously, we have demonstrated that hepatitis B virus (HBV) core particles tolerate the insertion of the amino-terminal 120 amino acids (aa) of the Puumala hantavirus nucleocapsid (N) protein. Here, we demonstrate that the insertion of 120 amino-terminal aa of N proteins from highly virulent Dobrava and Hantaan hantaviruses allows the formation of chimeric core particles. These particles expose the inserted foreign protein segments, at least in part, on their surface. Analysis by electron cryomicroscopy of chimeric particles harbouring the Puumala virus (PUUV) N segment revealed 90% T = 3 and 10% T = 4 shells. A map computed from T = 3 shells shows additional density splaying out from the tips of the spikes producing the effect of an extra shell of density at an outer radius compared with wild-type shells. The inserted Puumala virus N protein segment is flexibly linked to the core spikes and only partially icosahedrally ordered. Immunisation of mice of two different haplotypes (BALB/c and C57BL/6) with chimeric core particles induces a high-titered and highly cross-reactive N-specific antibody response in both mice strains

  14. Thrombin generation assay as a possible tool for assessment of reduced activity of clotting factors induced by antiphospholipid antibodies and in-vitro evaluation of treatment options.

    Science.gov (United States)

    Livnat, Tami; Zivelin, Ariella; Tamarin, Ilia; Guetta, Victor; Salomon, Ophira

    2009-12-01

    Bleeding is a rare manifestation of antiphospholipid syndrome, unless associated with reduced clotting factors or severe thrombocytopenia. Accurate assessment of the autoantibodies in plasma is very important since the autoantibodies can lead to bleeding or thrombosis. The objective of the present study was to define the inhibitors causing reduced clotting activity in a patient with antiphospholipids antibodies and to assess the potential of thrombin generation assay to assist in establishment of optimal treatment in case of major bleeding. Levels of clotting factors as well as inhibitors to factors II, V, VII, VIII, IX, X and XI were defined. For detection of inhibitors to prothrombin crossed immunoelectrophoresis was used. IgG was purified by commercial protein A column. Thrombin generation was measured using a fluorometric assay in platelet-poor and platelet-rich plasma. Inhibitors toward the activity of factors V, VII, VIII, IX, X and XI were defined and also an inhibitor to prothrombin antigen. No thrombin generation was induced in the patient's plasma by recalcification even in the presence of recombinant factor VIIa or factor VIII inhibitor bypassing activity. In contrast, addition of platelets from either donor or patient or synthetic phospholipids normalized the thrombin generation. The thrombin generation model showed that the addition of platelets and no recombinant factor VIIa or factor VIII inhibitor bypassing activity would correct thrombin generation in vitro. On this basis, platelet concentrates were administered to a patient with bleeding caused by lupus anticoagulant and low clotting factors activity.

  15. Combination of monoclonal antibodies with DST inhibits accelerated rejection mediated by memory T cells to induce long-lived heart allograft acceptance in mice.

    Science.gov (United States)

    Shao, Wei; Chen, Jibing; Dai, Helong; Peng, Yuanzheng; Wang, Feng; Xia, Junjie; Thorlacius, Henrik; Zhu, Qi; Qi, Zhongquan

    2011-08-30

    Donor-reactive memory T cells mediated accelerated rejection is known as a barrier to the survival of transplanted organs. We investigated the combination of different monoclonal antibodies (mAbs) and donor-specific transfusion (DST) in memory T cells-based adoptive mice model. In the presence of donor-reactive memory T cells, the mean survival time (MST) of grafts in the anti-CD40L/LFA-1/DST group was 49.8d. Adding anti-CD44/CD70 mAbs to anti-CD40L/LFA-1/DST treatment. The MST was more than 100 d (MST>100 d). Compared with anti-CD40L/LFA-1/DST group, anti-CD40L/LFA-1/CD44/CD70/DST group notably reduced the expansion of memory T cells, enhanced the proportion of CD4+Foxp3+ regulatory T cells (Tregs) and suppressed donor-specific responses. Our data suggest that anti-CD40L/LFA-1/CD44/CD70mAbs and DST can synergistically inhibit accelerated rejection mediated by memory T cells to induce long-lived heart allograft acceptance in mice. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Commercial bacterins did not induce detectable levels of antibodies in mice against Mycoplasma hyopneumoniae antigens strongly recognized by swine immune system

    Directory of Open Access Journals (Sweden)

    Andressa Fisch

    2016-01-01

    Full Text Available Enzootic Pneumonia (EP caused by Mycoplasma hyopneumoniae results in major economic losses to the swine industry. Hence, the identification of factors that provide protection against EP could help to develop effective vaccines. One such factor that provides partial protection are bacterins. Therefore, the aim of this study was to verify the induction of antibodies against fifteen M. hyopneumoniae antigens, strongly recognized by the swine immune system during natural infection, in mice vaccinated with six commercial bacterins. Each group of mice was inoculated with one bacterin, and seroconversion was assessed by indirect ELISA using recombinant antigens and M. hyopneumoniae 7448 whole cell extract. Sera from one inoculated group recognized antigen MHP_0067, and sera from four inoculated groups recognized antigens MHP_0513 and MHP_0580. None of the bacterins was able to induce seroconversion against the twelve remaining antigens. This absence of a serological response could be attributed to the lack of antigen expression in M. hyopneumoniae strains used in bacterin production. Additionally the partial protection provided by these vaccines could be due to low expression or misfolding of antigens during vaccine preparation. Therefore, the supplementation of bacterins with these recombinant antigens could be a potential alternative in the development of more effective vaccines.

  17. Beyond Antibodies: B Cells and the OPG/RANK-RANKL Pathway in Health, Non-HIV Disease and HIV-Induced Bone Loss

    Directory of Open Access Journals (Sweden)

    Kehmia Titanji

    2017-12-01

    Full Text Available HIV infection leads to severe B cell dysfunction, which manifests as impaired humoral immune response to infection and vaccinations and is not completely reversed by otherwise effective antiretroviral therapy (ART. Despite its inability to correct HIV-induced B cell dysfunction, ART has led to significantly increased lifespans in people living with HIV/AIDS. This has in turn led to escalating prevalence of non-AIDS complications in aging HIV-infected individuals, including malignancies, cardiovascular disease, bone disease, and other end-organ damage. These complications, typically associated with aging, are a significant cause of morbidity and mortality and occur significantly earlier in HIV-infected individuals. Understanding the pathophysiology of these comorbidities and delineating clinical management strategies and potential cures is gaining in importance. Bone loss and osteoporosis, which lead to increase in fragility fracture prevalence, have in recent years emerged as important non-AIDS comorbidities in patients with chronic HIV infection. Interestingly, ART exacerbates bone loss, particularly within the first couple of years following initiation. The mechanisms underlying HIV-induced bone loss are multifactorial and complicated by the fact that HIV infection is linked to multiple risk factors for osteoporosis and fracture, but a very interesting role for B cells in HIV-induced bone loss has recently emerged. Although best known for their important antibody-producing capabilities, B cells also produce two cytokines critical for bone metabolism: the key osteoclastogenic cytokine receptor activator of NF-κB ligand (RANKL and its physiological inhibitor osteoprotegerin (OPG. Dysregulated B cell production of OPG and RANKL was shown to be a major contributor to increased bone loss and fracture risk in animal models and HIV-infected humans. This review will summarize our current knowledge of the role of the OPG/RANK–RANKL pathway in B

  18. Therapeutic effects of antigen affinity-purified polyclonal anti-receptor of advanced glycation end-product (RAGE) antibodies on cholestasis-induced liver injury in rats.

    Science.gov (United States)

    Xia, Peng; Deng, Qing; Gao, Jin; Yu, Xiaolan; Zhang, Yang; Li, Jingjing; Guan, Wen; Hu, Jianjun; Tan, Quanhui; Zhou, Liang; Han, Wei; Yuan, Yunsheng; Yu, Yan

    2016-05-15

    Cholestasis leads to acute hepatic injury, fibrosis/cirrhosis, inflammation, and duct proliferation. We investigated whether blocking receptor of advanced glycation end-products (RAGE) with polyclonal anti-RAGE antibodies (anti-RAGE) could regulate acute liver injury and fibrosis in a rat bile duct ligation (BDL) model. Male Wister rats received 0.5mg/kg rabbit anti-RAGE or an equal amount of rabbit IgG by subcutaneous injection twice a week after BDL. Samples of liver tissue and peripheral blood were collected at 14 days after BDL. Serum biochemistry and histology were used to analyze the degree of liver injury. Quantitative real-time PCR (qPCR) and immunohistochemical staining were used to further analyze liver injury. Anti-RAGE improved the gross appearance of the liver and the rat survival rate. Liver tissue histology and relevant serum biochemistry indicated that anti-RAGE attenuated liver necrosis, inflammation, liver fibrosis, and duct proliferation in the BDL model. qPCR and western blotting showed significant reductions in interleukin-1β expression levels in the liver by treatment with anti-RAGE. Anti-RAGE also significantly reduced the mRNA levels of α1(1) collagen (Col1α1) and cholesterol 7α-hydroxylase, and the ratio of tissue inhibitor of matrix metalloproteinase-1 to matrix metalloproteinases (MMPs) in the liver. In addition, anti-RAGE regulated the transcriptional level of Col1α1 and MMP-9 in transforming growth factor-β-induced activated LX-2 cells in vitro. Anti-RAGE was found to inhibit hepatic stellate cell proliferation in vivo and in vitro. Therefore, anti-RAGE can protect the liver from injury induced by BDL in rats. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Ovalbumin-coated pH-sensitive microneedle arrays effectively induce ovalbumin-specific antibody and T-cell responses in mice.

    Science.gov (United States)

    van der Maaden, Koen; Varypataki, Eleni Maria; Romeijn, Stefan; Ossendorp, Ferry; Jiskoot, Wim; Bouwstra, Joke

    2014-10-01

    The aim of this work was to study the applicability of antigen-coated pH-sensitive microneedle arrays for effective vaccination strategies. Therefore, a model antigen (ovalbumin) was coated onto pH-sensitive (pyridine-modified) microneedle arrays to test pH-triggered antigen release by applying the coated arrays onto ex vivo human skin, and by conducting a dermal immunization study in mice. The release of antigen into ex vivo human skin from the coated microneedles was determined by using radioactively labeled ovalbumin. To investigate the induction of antigen-specific IgG, and CD4(+) and CD8(+) T-cell responses, BALB/c mice were immunized with antigen-coated pH-sensitive microneedles by the 'coat and poke' approach. These responses were compared to responses induced by the 'poke and patch' approach, and subcutaneous and intradermal vaccination with classic hypodermic needles. The pH-sensitive microneedle arrays were efficiently coated with ovalbumin (95% coating efficiency) and upon application of six microneedle arrays 4.27 of 7 μg ovalbumin was delivered into the skin, showing a release efficiency of 70%. In contrast, the 'poke and patch' approach led to a delivery of only 6.91 of 100 μg ovalbumin (7% delivery efficiency). Immunization by means of ovalbumin-coated microneedles resulted in robust CD4(+) and CD8(+) T-cell responses comparable to those obtained after subcutaneous or intradermal immunization with conventional needles. Moreover, it effectively induced IgG responses; however, it required prime-boost immunizations before antibodies were produced. In conclusion, antigen delivery into ex vivo human skin by antigen-coated pH-sensitive microneedle arrays is more efficient than the 'poke-and-patch' approach and in vivo vaccination studies show the applicability of pH-sensitive microneedles for the induction of both T cell and B cell responses. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Luminol-dependent chemiluminescence in antibody-sensitized neutrophils stimulated with protein A-bearing staphylococci.

    Science.gov (United States)

    Nishihara, S; Seki, K; Ikigai, H; Masuda, S

    1988-01-01

    When mouse polymorphonuclear leukocytes (PMNs) sensitized with rabbit antibody to mouse Ehrlich ascites tumor cells were stimulated by Staphylococcus aureus Cowan I cells, a conspicuous luminol-dependent chemiluminescence was observed in the absence of opsonin. The profile of the chemiluminescence (CL) response evoked by staphylococcal cells from antibody-sensitized PMNs had two peaks. An initial peak, observed within 1 min after stimulation, was sharp and high and a second peak, observed about 5 min after stimulation, was low and extended. The CL response of antibody-sensitized PMNs stimulated by S. aureus Cowan I cells was dose-dependently blocked by preincubation with soluble SpA. Cells of a mutant derived from S. aureus Cowan I strain with trace amounts of cell-bound SpA failed to stimulate the antibody-sensitized PMNs to generate the CL response. The antibody-sensitized PMNs were found to phagocytize SpA-bearing S. aureus cells even in the absence of opsonic serum. These results suggest that the observation presented here might provide a useful tool for the investigation of CL response of PMNs.

  1. Patterns of protective associations differ for antibodies to P. falciparum-infected erythrocytes and merozoites in immunity against malaria in children.

    Science.gov (United States)

    Chan, Jo-Anne; Stanisic, Danielle I; Duffy, Michael F; Robinson, Leanne J; Lin, Enmoore; Kazura, James W; King, Christopher L; Siba, Peter M; Fowkes, Freya Ji; Mueller, Ivo; Beeson, James G

    2017-12-01

    Acquired antibodies play an important role in immunity to P. falciparum malaria and are typically directed towards surface antigens expressed by merozoites and infected erythrocytes (IEs). The importance of specific IE surface antigens as immune targets remains unclear. We evaluated antibodies and protective associations in two cohorts of children in Papua New Guinea. We used genetically-modified P. falciparum to evaluate the importance of PfEMP1 and a P. falciparum isolate with a virulent phenotype. Our findings suggested that PfEMP1 was the dominant target of antibodies to the IE surface, including functional antibodies that promoted opsonic phagocytosis by monocytes. Antibodies were associated with increasing age and concurrent parasitemia, and were higher among children exposed to a higher force-of-infection as determined using molecular detection. Antibodies to IE surface antigens were consistently associated with reduced risk of malaria in both younger and older children. However, protective associations for antibodies to merozoite surface antigens were only observed in older children. This suggests that antibodies to IE surface antigens, particularly PfEMP1, play an earlier role in acquired immunity to malaria, whereas greater exposure is required for protective antibodies to merozoite antigens. These findings have implications for vaccine design and serosurveillance of malaria transmission and immunity. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Chronic treatment of (+)-methamphetamine-induced locomotor effects in rats using one or a combination of two high affinity anti-methamphetamine monoclonal antibodies.

    Science.gov (United States)

    Hambuchen, Michael D; Rüedi-Bettschen, Daniela; Gunnell, Melinda G; Hendrickson, Howard; Owens, S Michael

    2016-09-01

    We hypothesized that treatment of methamphetamine (METH) effects with a mixture of 2 high affinity anti-METH monoclonal antibodies (mAb) with differing molecular recognition for METH-like structures could increase efficacy compared to treatment with a single mAb. The antibodies studied were mAb7F9 (METH and amphetamine [AMP] KD = 7.7 and 270 nM) and mAb4G9 (16 nM and 110 nM, respectively) in a 50:50 mixture. Adult male Sprague Dawley Rats were treated with iv saline or a loading dose of mAb7F9-mAb4G9 (141 mg/kg of each mAb) followed by 2 weekly doses (70.5 mg/kg total) on days 7 and 14. METH challenge doses (0.56 mg/kg) were administered 4 hrs and 3 days after each mAb7F9-mAb4G9 treatment, and 7 days after the final treatment (day 21). Locomotor activity (0-4 hrs) and serum METH and AMP concentrations (at 5 hrs) were measured after each METH challenge. MAb7F9-mAb4G9 treatment significantly reduced the duration of locomotor activity after 6 of the 7 METH doses (P treatment had negligible effects on the duration of METH-induced locomotor activity. These data were then compared to previous monotherapy data. While mAb7F9-mAb4G9 therapy inhibited the effects of multiple METH challenge doses, the inhibition was not as profound or as long lasting as the effects of mAb7F9 treatment alone. These data demonstrate the importance of both mAb affinity and specificity in the production of effective, long-lasting anti-METH mAb therapies.

  3. Immunization of pregnant cows with Shiga toxin-2 induces high levels of specific colostral antibodies and lactoferrin able to neutralize E. coli O157:H7 pathogenicity.

    Science.gov (United States)

    Albanese, Adriana; Sacerdoti, Flavia; Seyahian, E Abril; Amaral, Maria Marta; Fiorentino, Gabriela; Fernandez Brando, Romina; Vilte, Daniel A; Mercado, Elsa C; Palermo, Marina S; Cataldi, Angel; Zotta, Elsa; Ibarra, Cristina

    2018-03-20

    E. coli O157:H7 is a foodborne pathogen responsible for bloody diarrhea, hemorrhagic colitis and hemolytic uremic syndrome (HUS). The objective of the present work was to evaluate the ability of colostral IgG obtained from Stx2-immunized cows to prevent against E. coli O157:H7 infection and Stx2 cytotoxicity. Hyperimmune colostrum (HC) was obtained from cows intramuscularly immunized with inactivated Stx2 or vehicle for controls. Colostral IgG was purified by affinity chromatography. Specific IgG antibodies against Stx2 and bovine lactoferrin (bLF) levels in HC and the corresponding IgG (HC-IgG/bLF) were determined by ELISA. The protective effects of HC-IgG/bLF against Stx2 cytotoxicity and adhesion of E. coli O157:H7 and its Stx2-negative mutant were analyzed in HCT-8 cells. HC-IgG/bLF prevention against E. coli O157:H7 was studied in human colon and rat colon loops. Protection against a lethal dose of E. coli O157:H7 was evaluated in a weaned mice model. HC-IgG/bLF showed high anti-Stx2 titers and high bLF levels that were able to neutralize the cytotoxic effects of Stx2 in vitro and in vivo. Furthermore, HC-IgG/bLF avoided the inhibition of water absorption induced by E. coli O157:H7 in human colon and also the pathogenicity of E. coli O157:H7 and E. coli O157:H7Δstx2 in rat colon loops. Finally, HC-IgG/bLF prevented in a 100% the lethality caused by E. coli O157:H7 in a weaned mice model. Our study suggests that HC-IgG/bLF have protective effects against E. coli O157:H7 infection. These beneficial effects may be due to specific anti-Stx2 neutralizing antibodies in combination with high bLF levels. These results allow us to consider HC-IgG/bLF as a nutraceutical tool which could be used in combination with balanced supportive diets to prevent HUS. However further studies are required before recommendations can be made for therapeutic and clinical applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Cell-induced potentiation of the plasminogen activation system is abolished by a monoclonal antibody that recognizes the NH2-terminal domain of the urokinase receptor

    DEFF Research Database (Denmark)

    Rønne, E; Behrendt, N; Ellis, V

    1991-01-01

    We have raised four monoclonal antibodies recognizing different epitopes within the human cell-surface receptor for urokinase-type plasminogen activator (u-PA). One of these antibodies completely abolishes the potentiation of plasmin generation observed upon incubation of the zymogens pro...

  5. De Novo Circulating Antidonor's Cell Antibodies During Induced Acute Rejection of Allogeneic Myofibers in Myogenic Cell Transplantation: A Study in Nonhuman Primates

    Directory of Open Access Journals (Sweden)

    Daniel Skuk, MD

    2017-12-01

    Conclusions. Flow cytometry detection of de novo circulating antibodies against the donor’s cells was consistently associated with AR. A clear increase in this antibody detection indicated current or recent AR. Smaller increases in comparison to the preimmunosuppression values were not associated with AR.

  6. Complement protein C1q induces maturation of human dendritic cells.

    Science.gov (United States)

    Csomor, Eszter; Bajtay, Zsuzsa; Sándor, Noémi; Kristóf, Katalin; Arlaud, Gérard J; Thiel, Steffen; Erdei, Anna

    2007-07-01

    Maturation of dendritic cells (DCs) is known to be induced by several stimuli, including microbial products, inflammatory cytokines and immobilized IgG, as demonstrated recently. Since immune complexes formed in vivo also contain C1q, moreover apoptotic cells and several pathogens fix C1q in the absence of antibodies, we undertook to investigate whether this complement protein has an impact on various functions of human DCs. Maturation of monocyte-derived immature DCs (imMDCs) cultured on immobilized C1q was followed by monitoring expression of CD80, CD83, CD86, MHCII and CCR7. The functional activity of the cells was assessed by measuring cytokine secretion and their ability to activate allogeneic T lymphocytes. Cytokine production by T cells co-cultured with C1q-matured DCs was also investigated. C1q, but not the structurally related mannose-binding lectin was found to bind to imMDC in a dose-dependent manner and induced NF-kappaB translocation to the nucleus. Immobilized C1q induced maturation of MDCs and enhanced secretion of IL-12 and TNF-alpha, moreover, elevated their T-cell stimulating capacity. As IFN-gamma levels were increased in supernatants of MDC-T cell co-cultures, our data suggest that C1q-induced DC maturation generates a Th1-type response. Interestingly, IL-10 levels were elevated by C1q-treated MDCs but not in the supernatant of their co-cultures with allogeneic T cells. Taken together, these results indicate that C1q-opsonized antigens may play a role in the induction and regulation of immune response. Moreover our data are relevant in view of the role of C1q in removal of apoptotic cells and the association between C1q-deficiency and autoimmunity.

  7. Opsonophagocytic Antibodies to Serotype Ia, Ib, and III Group B Streptococcus among Korean Infants and in Intravenous Immunoglobulin Products.

    Science.gov (United States)

    Kim, Han Wool; Lee, Ji Hyen; Cho, Hye Kyung; Lee, Hyunju; Seo, Ho Seong; Lee, Soyoung; Kim, Kyung Hyo

    2017-05-01

    Group B streptococcus (GBS) infection is a leading cause of sepsis and meningitis among infants, and is associated with high rates of morbidity and mortality in many countries. Protection against GBS typically involves antibody-mediated opsonization by phagocytes and complement components. The present study evaluated serotype-specific functional antibodies to GBS among Korean infants and in intravenous immunoglobulin (IVIG) products. An opsonophagocytic killing assay (OPA) was used to calculate the opsonization indices (OIs) of functional antibodies to serotypes Ia, Ib, and III in 19 IVIG products from 5 international manufacturers and among 98 Korean infants (age: 0-11 months). The GBS Ia, Ib, and III serotypes were selected because they are included in a trivalent GBS vaccine formulation that is being developed. The OI values for the IVIG products were 635-5,706 (serotype Ia), 488-1,421 (serotype Ib), and 962-3,315 (serotype III), and none of the IVIG lots exhibited undetectable OI values (Korean manufacturers. The seropositive rate among infants was significantly lower for serotype Ia (18.4%), compared to serotype Ib and serotype III (both, 38.8%). Infant age of ≥ 3 months was positively correlated with the seropositive rates for each serotype. Therefore, only a limited proportion of infants exhibited protective immunity against serotype Ia, Ib, and III GBS infections. IVIG products that exhibit high antibody titers may be a useful therapeutic or preventive measure for infants. Further studies are needed to evaluate additional serotypes and age groups. © 2017 The Korean Academy of Medical Sciences.

  8. Systemic antibody responses induced by a two-component Clostridium difficile toxoid vaccine protect against C. difficile-associated disease in hamsters.

    Science.gov (United States)

    Anosova, Natalie G; Brown, Anna M; Li, Lu; Liu, Nana; Cole, Leah E; Zhang, Jinrong; Mehta, Hersh; Kleanthous, Harry

    2013-09-01

    measurements of pre-challenge sera showed that the median anti-toxin A and anti-toxin B IgG titres in the group of surviving animals were significantly higher than the median values in the group of animals that did not survive challenge. Assessment of the neutralizing activity of these sera revealed a statistically significant difference between the levels of both toxin A and toxin B neutralizing titres in protected versus unprotected animals as the median anti-toxin A and anti-toxin B neutralizing titres from surviving animals were higher than the median values from animals that succumbed to challenge. Statistically significant correlations between the toxin-specific binding titres and toxin neutralizing titres were seen for both toxin A and toxin B responses. The role of circulating anti-toxin antibodies in immunity against disease was evaluated by passive transfer of immune sera against C. difficile toxoids to naïve hamsters. Passively immunized animals were protected against morbidity and mortality associated with C. difficile challenge. Taken together, these results indicate the ability of i.m. immunization with inactivated toxins A and B to induce robust dose-dependent anti-toxin A and anti-toxin B IgG responses, the principal role of circulating anti-toxin antibody in immunity against disease and that antibody toxin binding and neutralization titres can serve as correlates of protection in the hamster challenge model of C. difficile.

  9. Neutralizing antibodies induced by recombinant virus-like particles of enterovirus 71 genotype C4 inhibit infection at pre- and post-attachment steps.

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    Zhiqiang Ku

    Full Text Available BACKGROUND: Enterovirus 71 (EV71 is a major causative agent of hand, foot and mouth disease, which has been prevalent in Asia-Pacific regions, causing significant morbidity and mortality in young children. Antibodies elicited by experimental EV71 vaccines could neutralize infection in vitro and passively protect animal models from lethal challenge, indicating that neutralizing antibodies play an essential role in protection. However, how neutralizing antibodies inhibit infection in vitro remains unclear. METHODS/FINDINGS: In the present study, we explored the mechanisms of neutralization by antibodies against EV71 virus-like particles (VLPs. Recombinant VLPs of EV71 genotype C4 were produced in insect cells using baculovirus vectors. Immunization with the VLPs elicited a high-titer, EV71-specific antibody response in mice. Anti-VLP mouse sera potently neutralized EV71 infection in vitro. The neutralizing antibodies in the anti-VLP mouse sera were found to target mainly an extremely conserved epitope (FGEHKQEKDLEYGAC located at the GH loop of the VP1 protein. The neutralizing anti-VLP antisera were able to inhibit virus binding to target cells efficiently. In addition, post-attachment treatment of virus-bound cells with the anti-VLP antisera also neutralized virus infection, although the antibody concentration required was higher than that of the pre-attachment treatment. CONCLUSIONS: Collectively, our findings represent a valuable addition to the understanding of mechanisms of EV71 neutralization and have strong implications for EV71 vaccine development.

  10. Inhibition of the Myotoxicity Induced by Bothrops jararacussu Venom and Isolated Phospholipases A2 by Specific Camelid Single-Domain Antibody Fragments.

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    Nidiane D R Prado

    Full Text Available Antivenoms, produced using animal hyperimmune plasma, remains the standard therapy for snakebites. Although effective against systemic damages, conventional antivenoms have limited efficacy against local tissue damage. Additionally, the hypersensitivity reactions, often elicited by antivenoms, the high costs for animal maintenance, the difficulty of producing homogeneous lots, and the instability of biological products instigate the search for innovative products for antivenom therapy. In this study, camelid antibody fragments (VHH with specificity to Bothropstoxin I and II (BthTX-I and BthTX-II, two myotoxic phospholipases from Bothrops jararacussu venom, were selected from an immune VHH phage display library. After biopanning, 28 and 6 clones recognized BthTX-I and BthTX-II by ELISA, respectively. Complementarity determining regions (CDRs and immunoglobulin frameworks (FRs of 13 VHH-deduced amino acid sequences were identified, as well as the camelid hallmark amino acid substitutions in FR2. Three VHH clones (KF498607, KF498608, and KC329718 were capable of recognizing BthTX-I by Western blot and showed affinity constants in the nanomolar range against both toxins. VHHs inhibited the BthTX-II phospholipase A2 activity, and when tested for cross-reactivity, presented specificity to the Bothrops genus in ELISA. Furthermore, two clones (KC329718 and KF498607 neutralized the myotoxic effects induced by B. jararacussu venom, BthTX-I, BthTX-II, and by a myotoxin from Bothrops brazili venom (MTX-I in mice. Molecular docking revealed that VHH CDRs are expected to bind the C-terminal of both toxins, essential for myotoxic activity, and to epitopes in the BthTX-II enzymatic cleft. Identified VHHs could be a biotechnological tool to improve the treatment for snake envenomation, an important and neglected world public health problem.

  11. Critical role for IL-17A/F in the immunopathogenesis of obliterative airway disease induced by Anti-MHC I antibodies.

    Science.gov (United States)

    Basha, Haseeb Ilias; Ramachandran, Sabarinathan; Tiriveedhi, Venkataswarup; Takenaka, Masashi; Subramanian, Vijay; Nath, Dilip S; Benshoff, Nicholas; Patterson, G Alec; Mohanakumar, Thalachallour

    2013-01-27

    The IL-17 axis is implicated in pathogenesis of chronic rejection after human lung transplantation. Using a murine model of obliterative airway disease (OAD), we recently demonstrated that Abs to MHC class I antigens can induce immune responses to self-antigens that contributes to immunopathogenesis of chronic rejection. Using a murine model of OAD, we determined the role of IL-17 family members in induction of autoimmunity leading to OAD after ligation of MHC class I. Anti-MHC class I or control antibodies (Abs) were administered intrabronchially to wild-type (WT) and IL-17a knock out (IL-17A-/-) C57BL/6. By day 30, anti-MHC I administered endobronchially in IL-17A-/- mice demonstrated significant reduction in cellular infiltration, a 36.8% reduction in CD4 T cells, 62.7% in CD11b macrophages, 37.5% in degree of fibrosis, 1.94 fold and 2.17 fold decrease in anti-KAT and anti-Col-V, respectively, when compared with wild-type mice. Analysis of lung infiltrating cells in anti-MHC I WT revealed increase in IL-17A (KAT:92+21,Col-V:103+19spm) and IL-17F (KAT:5.03%,Col-V:2.75%) secreting CD4+ T cells. However, administration of anti-MHC I in IL-17A-/- demonstrated increase only in IL-17F for KAT (13.70%) and Col-V (7.08%). Anti-IL-17(A-F) mAb administration after anti-MHC I abrogated OAD in both WT and IL-17A-/-. Our findings indicate that IL-17A and IL-17F secreted by CD4+Th17 cells specific to lung self-antigens are critical mediators of autoimmunity leading to the pathogenesis of OAD.

  12. Detrimental roles of TNF-alpha in the antiphospholipid syndrome and de novo synthesis of antiphospholipid antibodies induced by biopharmaceuticals against TNF-alpha.

    Science.gov (United States)

    Bećarević, Mirjana

    2017-11-01

    Antiphospholipid syndrome (APS) is an autoimmune disease that is characterized by arterial and/or venous thrombosis and/or recurrent pregnancy losses. Obstetric APS (OAPS) is considered as a distinct entity from vascular APS (VAPS). In the absence of any additional disease, APS is designated as primary (PAPS), while the term secondary APS (SAPS) is used when other diseases are associated. Catastrophic APS (CAPS) is characterized by the rapid development of multiple thrombosis in various vital organs. The presence of antiphospholipid antibodies (aPL Abs) is considered as a laboratory criterion for APS diagnosis. aPL Abs cause an increase in systemic and decidual TNF-alpha levels in experimental model of APS (eAPS), while paradoxically, administration of TNF-alpha blockers has been associated with de novo synthesis of aPL Abs in patients with various autoimmune diseases. While eAPS provides evidence for the fact that application of TNF-alpha blockers has beneficial effects, lack of randomized prospective studies is the main obstacle for consideration of TNF-alpha blockers administration as a therapeutic option not for all, but at least for selected cases of APS patients despite compelling evidence for detrimental roles of TNF-alpha for both VASP and OAPS. This article represents a review of previously published reports on detrimental roles of TNF-alpha in APS, reports on the application of anti-TNF-alpha agents in eAPS and articles that reported de novo synthesis of aPL Abs induced by biopharmaceuticals against TNF-alpha.

  13. Dengue type four viruses with E-Glu345Lys adaptive mutation from MRC-5 cells induce low viremia but elicit potent neutralizing antibodies in rhesus monkeys.

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    Hsiao-Han Lin

    Full Text Available Knowledge of virulence and immunogenicity is important for development of live-attenuated dengue vaccines. We previously reported that an infectious clone-derived dengue type 4 virus (DENV-4 passaged in MRC-5 cells acquired a Glu345Lys (E-E345K substitution in the E protein domain III (E-DIII. The same cloned DENV-4 was found to yield a single E-Glu327Gly (E-E327G mutation after passage in FRhL cells and cause the loss of immunogenicity in rhesus monkeys. Here, we used site-directed mutagenesis to generate the E-E345K and E-E327G mutants from DENV-4 and DENV-4Δ30 infectious clones and propagated in Vero or MRC-5 cells. The E-E345K mutations were consistently presented in viruses recovered from MRC-5 cells, but not Vero cells. Recombinant E-DIII proteins of E345K and E327G increased heparin binding correlated with the reduced infectivity by heparin treatment in cell cultures. Different from the E-E327G mutant viruses to lose the immunogencity in rhesus monkeys, the E-E345K mutant viruses were able to induce neutralizing antibodies in rhesus monkeys with an almost a 10-fold lower level of viremia as compared to the wild type virus. Monkeys immunized with the E-E345K mutant virus were completely protected with no detectable viremia after live virus challenges with the wild type DENV-4. These results suggest that the E-E345K mutant virus propagated in MRC-5 cells may have potential for the use in live-attenuated DENV vaccine development.

  14. Dengue type four viruses with E-Glu345Lys adaptive mutation from MRC-5 cells induce low viremia but elicit potent neutralizing antibodies in rhesus monkeys.

    Science.gov (United States)

    Lin, Hsiao-Han; Lee, Hsiang-Chi; Li, Xiao-Feng; Tsai, Meng-Ju; Hsiao, Hung-Ju; Peng, Jia-Guan; Sue, Shih-Che; Qin, Cheng-Feng; Wu, Suh-Chin

    2014-01-01

    Knowledge of virulence and immunogenicity is important for development of live-attenuated dengue vaccines. We previously reported that an infectious clone-derived dengue type 4 virus (DENV-4) passaged in MRC-5 cells acquired a Glu345Lys (E-E345K) substitution in the E protein domain III (E-DIII). The same cloned DENV-4 was found to yield a single E-Glu327Gly (E-E327G) mutation after passage in FRhL cells and cause the loss of immunogenicity in rhesus monkeys. Here, we used site-directed mutagenesis to generate the E-E345K and E-E327G mutants from DENV-4 and DENV-4Δ30 infectious clones and propagated in Vero or MRC-5 cells. The E-E345K mutations were consistently presented in viruses recovered from MRC-5 cells, but not Vero cells. Recombinant E-DIII proteins of E345K and E327G increased heparin binding correlated with the reduced infectivity by heparin treatment in cell cultures. Different from the E-E327G mutant viruses to lose the immunogencity in rhesus monkeys, the E-E345K mutant viruses were able to induce neutralizing antibodies in rhesus monkeys with an almost a 10-fold lower level of viremia as compared to the wild type virus. Monkeys immunized with the E-E345K mutant virus were completely protected with no detectable viremia after live virus challenges with the wild type DENV-4. These results suggest that the E-E345K mutant virus propagated in MRC-5 cells may have potential for the use in live-attenuated DENV vaccine development.

  15. Regulation by anti-CD2 monoclonal antibody of the activation of a human T cell clone induced by anti-CD3 or anti-T cell receptor antibodies

    NARCIS (Netherlands)

    Yssel, H.; Aubry, J. P.; de Waal Malefijt, R.; de Vries, J. E.; Spits, H.

    1987-01-01

    In this study the effect of anti-cluster designation (CD) 2 monoclonal antibodies (mAb) on the activation of a cloned human T cell line, HY837, after triggering the CD3/T cell receptor (TcR) complex by anti-CD3 or anti-TcR mAb is described. HY837, which reacts with a series of mAb directed at

  16. Human Papillomavirus neutralizing and cross-reactive antibodies induced in HIV-positive subjects after vaccination with quadrivalent and bivalent HPV vaccines

    DEFF Research Database (Denmark)

    Faust, Helena; Nielsen, Lars Toft; Sehr, Peter

    2016-01-01

    of neutralizing and binding antibodies had good agreement (average Kappa for HPV types 6, 11, 16, 18, 31, 33 and 45 was 0.65). At baseline, 88% of subjects had antibodies against at least one genital HPV. Following vaccination with Cervarix™, all subjects became seropositive for HPV16 and 18. After Gardasil......™ vaccination, 96% of subjects seroconverted for HPV16 and 73% for HPV18. Levels of HPV16-specific antibodies were vaccination but >10IU in 85% of study subjects after vaccination. Antibodies against non-vaccine HPV types appeared after Gardasil......™ vaccination for >50% of vaccinated females for HPV 31, 35 and 73 and for >50% of Cervarix™-vaccinated females for HPV 31, 33, 35, 45, 56 and 58. Cross-reactivity with non-genital HPV types was also detected. In conclusion, HIV-infected subjects responded to HPV vaccination with induction of neutralizing...

  17. Generation of antibodies against disintegrin and cysteine-rich domains by DNA immunization: An approach to neutralize snake venom-induced haemorrhage

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    Sidgi Syed Anwer Abdo Hasson

    2017-03-01

    Conclusions: Antibodies generated against the E. ocellatus venom prothrombin activator-like metalloprotease and disintegrin-cysteine-rich domains modulated and inhibited the catalytic activity both in vitro and in vivo of venom metalloproteinase disintegrin cysteine rich molecules. Thus, generating of venom specific-toxin antibodies by DNA immunization offer a more rational treatment of snake envenoming than conventional antivenom.

  18. Replacing reprogramming factors with antibodies selected from combinatorial antibody libraries.

    Science.gov (United States)

    Blanchard, Joel W; Xie, Jia; El-Mecharrafie, Nadja; Gross, Simon; Lee, Sohyon; Lerner, Richard A; Baldwin, Kristin K

    2017-10-01

    The reprogramming of differentiated cells into induced pluripotent stem cells (iPSCs) is usually achieved by exogenous induction of transcription by factors acting in the nucleus. In contrast, during development, signaling pathways initiated at the membrane induce differentiation. The central idea of this study is to identify antibodies that can catalyze cellular de-differentiation and nuclear reprogramming by acting at the cell surface. We screen a lentiviral library encoding ∼100 million secreted and membrane-bound single-chain antibodies and identify antibodies that can replace either Sox2 and Myc (c-Myc) or Oct4 during reprogramming of mouse embryonic fibroblasts into iPSCs. We show that one Sox2-replacing antibody antagonizes the membrane-associated protein Basp1, thereby de-repressing nuclear factors WT1, Esrrb and Lin28a (Lin28) independent of Sox2. By manipulating this pathway, we identify three methods to generate iPSCs. Our results establish unbiased selection from autocrine combinatorial antibody libraries as a robust method to discover new biologics and uncover membrane-to-nucleus signaling pathways that regulate pluripotency and cell fate.

  19. The effect of dexamethasone-induced immunosuppression on the development of faecal antibody and recovery from and resistance to rotavirus infection.

    Science.gov (United States)

    Oldham, G; Bridger, J C

    1992-04-01

    Rotavirus-naive and rotavirus-immune gnotobiotic calves were treated with high doses of dexamethasone (DX) to suppress the immune system. Calves were then infected with a virulent rotavirus inoculum, J-160, to investigate the role of immune responses both in recovery from primary rotavirus infection and in resistance to secondary rotavirus infection. Treatment of calves with DX markedly suppressed in vitro responsiveness of peripheral blood lymphocytes to mitogens within 48 h of the start of DX treatment. Suppression was similar in rotavirus-naive and rotavirus-immune calves. In contrast, the effect of DX treatment on specific antibody responses differed depending on when DX treatment started in relation to rotavirus infection. When DX treatment commenced prior to primary rotavirus infection both systemic and local specific antibody responses were inhibited. These calves, in which mitogen and antibody responses were suppressed, exhibited greater clinical signs than did control calves after infection with virulent rotavirus, but virus excretion was affected in only one of the two calves. When DX treatment was started after primary rotavirus infection but before secondary infection, systemic and local antibody responses to the primary infection and to the challenge infection were not affected. These calves resisted challenge with virulent virus as did DX-untreated rotavirus-immune calves, even though mitogen responses were suppressed. We conclude that in a primary rotavirus infection, virus excretion ceased when both antibody and mitogen responses were suppressed. Resistance to secondary rotavirus infection occurred when mitogen responsiveness was suppressed, but when antibody levels were normal. Thus, no evidence was obtained that fully functional cell-mediated immune mechanisms are essential for resistance to rotavirus infection. Evidence was provided for the ability of parenteral treatment with DX to suppress mucosal as well as systemic antibody responses.

  20. Títulos de anticorpos aglutinantes induzidos por vacinas comerciais contra leptospirose bovina Agglutinating antibody titers induced by commercial vaccines against bovine leptospirosis

    Directory of Open Access Journals (Sweden)

    Gabriela de Godoy Cravo Arduino

    2009-07-01

    serovars. All vaccines used were capable to product agglutinins for the Hardjo and Wolffi serovars observed at 3 days after vaccination, remaining until the 150th day; those serovars induced the highest titres of agglutinins. Vaccine D, in spite of not containing the Wolffi serovar, induced the production of agglutinins to this serovar. Agglutinins to the Canicola serovar were only observed in the animals vaccinated with the D bacterine. Vaccine D induced the highest average titers of antibodies to all tested serovars.

  1. Exceptional Antibodies Produced by Successive Immunizations.

    Directory of Open Access Journals (Sweden)

    Patricia J Gearhart

    2015-12-01

    Full Text Available Antibodies stand between us and pathogens. Viruses mutate quickly to avoid detection, and antibodies mutate at similar rates to hunt them down. This death spiral is fueled by specialized proteins and error-prone polymerases that change DNA sequences. Here, we explore how B lymphocytes stay in the race by expressing activation-induced deaminase, which unleashes a tsunami of mutations in the immunoglobulin loci. This produces random DNA substitutions, followed by selection for the highest affinity antibodies. We may be able to manipulate the process to produce better antibodies by expanding the repertoire of specific B cells through successive vaccinations.

  2. A 12-Month-Interval Dosing Study in Adults Indicates That a Single Dose of the National Institute of Allergy and Infectious Diseases Tetravalent Dengue Vaccine Induces a Robust Neutralizing Antibody Response.

    Science.gov (United States)

    Durbin, Anna P; Kirkpatrick, Beth D; Pierce, Kristen K; Carmolli, Marya P; Tibery, Cecilia M; Grier, Palmtama L; Hynes, Noreen; Opert, Kari; Jarvis, Adrienne P; Sabundayo, Beulah P; McElvany, Benjamin D; Sendra, Eli A; Larsson, Catherine J; Jo, Matthew; Lovchik, Janece M; Luke, Catherine J; Walsh, Mary C; Fraser, Ellen A; Subbarao, Kanta; Whitehead, Stephen S

    2016-09-15

    The ideal dengue vaccine will provide protection against all serotypes of dengue virus and will be economical and uncomplicated in its administration. To determine the ability of a single dose of the live attenuated tetravalent dengue vaccine TV003 to induce a suitable neutralizing antibody response, a placebo-controlled clinical trial was performed in 48 healthy adults who received 2 doses of vaccine or placebo administered 12 months apart. Evaluation of safety, vaccine viremia, and neutralizing antibody response after each dose indicated that the first dose of vaccine was capable of preventing infection with the second dose, thus indicating that multiple doses are unnecessary. NCT01782300. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  3. An HIV-1 envelope immunogen with W427S mutation in CD4 binding site induced more T follicular helper memory cells and reduced non-specific antibody responses.

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    Hao-Tong Yu

    Full Text Available The CD4 binding site (CD4BS of the HIV-1 envelope glycoprotein (Env contains epitopes for broadly neutralizing antibody (nAb and is the target for the vaccine development. However, the CD4BS core including residues 425-430 overlaps the B cell superantigen site and may be related to B cell exhaustion in HIV-1 infection. Furthermore, production of nAb and high-affinity plasma cells needs germinal center reaction and the help of T follicular helper (Tfh cells. We believe that strengthening the ability of Env CD4BS in inducing Tfh response and decreasing the effects of the superantigen are the strategies for eliciting nAb and development of HIV-1 vaccine. We constructed a gp120 mutant W427S of an HIV-1 primary R5 strain and examined its ability in the elicitation of Ab and the production of Tfh by immunization of BALB/c mice. We found that the trimeric wild-type gp120 can induce more non-specific antibody-secreting plasma cells, higher serum IgG secretion, and more Tfh cells by splenocyte. The modified W427S gp120 elicits higher levels of specific binding antibodies as well as nAbs though it produces less Tfh cells. Furthermore, higher Tfh cell frequency does not correlate to the specific binding Abs or nAbs indicating that the wild-type gp120 induced some non-specific Tfh that did not contribute to the production of specific Abs. This gp120 mutant led to more memory Tfh production, especially, the effector memory Tfh cells. Taken together, W427S gp120 could induce higher level of specific binding and neutralizing Ab production that may be associated with the reduction of non-specific Tfh but strengthening of the memory Tfh.

  4. Recombinant Protein Truncation Strategy for Inducing Bactericidal Antibodies to the Macrophage Infectivity Potentiator Protein of Neisseria meningitidis and Circumventing Potential Cross-Reactivity with Human FK506-Binding Proteins

    Science.gov (United States)

    Bielecka, Magdalena K.; Devos, Nathalie; Gilbert, Mélanie; Hung, Miao-Chiu; Weynants, Vincent; Heckels, John E.

    2014-01-01

    A recombinant macrophage infectivity potentiator (rMIP) protein of Neisseria meningitidis induces significant serum bactericidal antibody production in mice and is a candidate meningococcal vaccine antigen. However, bioinformatics analysis of MIP showed some amino acid sequence similarity to human FK506-binding proteins (FKBPs) in residues 166 to 252 located in the globular domain of the protein. To circumvent the potential concern over generating antibodies that could recognize human proteins, we immunized mice with recombinant truncated type I rMIP proteins that lacked the globular domain and the signal leader peptide (LP) signal sequence (amino acids 1 to 22) and contained the His purification tag at either the N or C terminus (C-term). The immunogenicity of truncated rMIP proteins was compared to that of full (i.e., full-length) rMIP proteins (containing the globular domain) with either an N- or C-terminal His tag and with or without the LP sequence. By comparing the functional murine antibody responses to these various constructs, we determined that C-term His truncated rMIP (−LP) delivered in liposomes induced high levels of antibodies that bound to the surface of wild-type but not Δmip mutant meningococci and showed bactericidal activity against homologous type I MIP (median titers of 128 to 256) and heterologous type II and III (median titers of 256 to 512) strains, thereby providing at least 82% serogroup B strain coverage. In contrast, in constructs lacking the LP, placement of the His tag at the N terminus appeared to abrogate bactericidal activity. The strategy used in this study would obviate any potential concerns regarding the use of MIP antigens for inclusion in bacterial vaccines. PMID:25452551

  5. Recombinant protein truncation strategy for inducing bactericidal antibodies to the macrophage infectivity potentiator protein of Neisseria meningitidis and circumventing potential cross-reactivity with human FK506-binding proteins.

    Science.gov (United States)

    Bielecka, Magdalena K; Devos, Nathalie; Gilbert, Mélanie; Hung, Miao-Chiu; Weynants, Vincent; Heckels, John E; Christodoulides, Myron

    2015-02-01

    A recombinant macrophage infectivity potentiator (rMIP) protein of Neisseria meningitidis induces significant serum bactericidal antibody production in mice and is a candidate meningococcal vaccine antigen. However, bioinformatics analysis of MIP showed some amino acid sequence similarity to human FK506-binding proteins (FKBPs) in residues 166 to 252 located in the globular domain of the protein. To circumvent the potential concern over generating antibodies that could recognize human proteins, we immunized mice with recombinant truncated type I rMIP proteins that lacked the globular domain and the signal leader peptide (LP) signal sequence (amino acids 1 to 22) and contained the His purification tag at either the N or C terminus (C-term). The immunogenicity of truncated rMIP proteins was compared to that of full (i.e., full-length) rMIP proteins (containing the globular domain) with either an N- or C-terminal His tag and with or without the LP sequence. By comparing the functional murine antibody responses to these various constructs, we determined that C-term His truncated rMIP (-LP) delivered in liposomes induced high levels of antibodies that bound to the surface of wild-type but not Δmip mutant meningococci and showed bactericidal activity against homologous type I MIP (median titers of 128 to 256) and heterologous type II and III (median titers of 256 to 512) strains, thereby providing at least 82% serogroup B strain coverage. In contrast, in constructs lacking the LP, placement of the His tag at the N terminus appeared to abrogate bactericidal activity. The strategy used in this study would obviate any potential concerns regarding the use of MIP antigens for inclusion in bacterial vaccines. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  6. Breast tumor xenografts: diffusion-weighted MR imaging to assess early therapy with novel apoptosis-inducing anti-DR5 antibody.

    Science.gov (United States)

    Kim, Hyunki; Morgan, Desiree E; Zeng, Huadong; Grizzle, William E; Warram, Jason M; Stockard, Cecil R; Wang, Deli; Zinn, Kurt R

    2008-09-01

    To measure the early therapeutic response to a novel apoptosis-inducing antibody, TRA-8, by using diffusion-weighted magnetic resonance (MR) imaging in a mouse breast cancer model. Animal experiments had institutional animal care and use committee approval. Four groups of nude mice bearing luciferase-positive breast tumors (four to five mice with eight to 10 tumors per group) were injected intravenously with 0 mg (group 1), 0.025 mg (group 2), 0.100 mg (group 3), or 0.200 mg (group 4) of TRA-8 on days 0 and 3. Diffusion-weighted imaging, anatomic MR imaging, and bioluminescence imaging were performed on days 0, 3, and 6 before dosing. Averaged apparent diffusion coefficients (ADCs) for both whole tumor volume and a 1-mm peripheral tumor shell were calculated and were compared with tumor volume and living tumor cell changes. After imaging at day 6, proliferating and apoptotic cell densities were measured with Ki67 and terminal deoxynucleotidyl transferase mediated dUTP nick end labeling, or TUNEL, staining, respectively, and were compared with cleaved caspase-3 density. The ADC increase at day 3 was dependent on TRA-8 dose level, averaging 6% +/- 3 (standard error of mean), 19% +/- 4, 14% +/- 4, and 34% +/- 7 in the whole tumor volume and 1% +/- 2, 9% +/- 5, 13% +/- 5, and 30% +/- 8 in the outer 1-mm tumor shell only for groups 1, 2, 3, and 4, respectively. The ADC increase in group 4 was significantly higher (P = .0008 and P = .0189 for whole tumor volume and peripheral region, respectively) than that in group 1 on day 3, whereas tumor size did not significantly differ. At day 3, the dose-dependent ADC increases were linearly proportional to apoptotic cell and cleaved caspase-3 densities and were inversely proportional to the density of cells showing Ki67 expression. Diffusion-weighted imaging enabled measurement of early breast tumor response to TRA-8 treatment, prior to detectable tumor shrinkage, providing an effective mechanism to noninvasively monitor TRA-8

  7. Serum reactome induced by Bordetella pertussis infection and Pertussis vaccines: qualitative differences in serum antibody recognition patterns revealed by peptide microarray analysis.

    Science.gov (United States)

    Valentini, Davide; Ferrara, Giovanni; Advani, Reza; Hallander, Hans O; Maeurer, Markus J

    2015-07-01

    Pertussis (whooping cough) remains a public health problem despite extensive vaccination strategies. Better understanding of the host-pathogen interaction and the detailed B. pertussis (Bp) target recognition pattern will help in guided vaccine design. We characterized the specific epitope antigen recognition profiles of serum antibodies ('the reactome') induced by whooping cough and B. pertussis (Bp) vaccines from a case-control study conducted in 1996 in infants enrolled in a Bp vaccine trial in Sweden (Gustafsson, NEJM, 1996, 334, 349-355). Sera from children with whooping cough, vaccinated with Diphtheria Tetanus Pertussis (DTP) whole-cell (wc), acellular 5 (DPTa5), or with the 2 component (a2) vaccines and from infants receiving only DT (n=10 for each group) were tested with high-content peptide microarrays containing 17 Bp proteins displayed as linear (n=3175) peptide stretches. Slides were incubated with serum and peptide-IgG complexes detected with Cy5-labeled goat anti-human IgG and analyzed using a GenePix 4000B microarray scanner, followed by statistical analysis, using PAM (Prediction Analysis for Microarrays) and the identification of uniquely recognized peptide epitopes. 367/3,085 (11.9%) peptides were recognized in 10/10 sera from children with whooping cough, 239 (7.7%) in DTPwc, 259 (8.4%) in DTPa5, 105 (3.4%) DTPa2, 179 (5.8%) in the DT groups. Recognition of strongly recognized peptides was similar between whooping cough and DPTwc, but statistically different between whooping cough vs. DTPa5 (p<0.05), DTPa2 and DT (p<0.001 vs. both) vaccines. 6/3,085 and 2/3,085 peptides were exclusively recognized in (10/10) sera from children with whooping cough and DTPa2 vaccination, respectively. DTPwc resembles more closely the whooping cough reactome as compared to acellular vaccines. We could identify a unique recognition signature common for each vaccination group (10/10 children). Peptide microarray technology allows detection of subtle differences in

  8. Estimating Parameters Related to the Lifespan of Passively Transferred and Vaccine-Induced Porcine Reproductive and Respiratory Syndrome Virus Type I Antibodies by Modeling Field Data

    Directory of Open Access Journals (Sweden)

    Mathieu Andraud

    2018-01-01

    Full Text Available The outputs of epidemiological models are strongly related to the structure of the model and input parameters. The latter are defined by fitting theoretical concepts to actual data derived from field or experimental studies. However, some parameters may remain difficult to estimate and are subject to uncertainty or sensitivity analyses to determine their variation range and their global impact on model outcomes. As such, the evaluation of immunity duration is often a puzzling issue requiring long-term follow-up data that are, most of time, not available. The present analysis aims at characterizing the kinetics of antibodies against Porcine Reproductive and Respiratory Syndrome virus (PRRSv from longitudinal data sets. The first data set consisted in the serological follow-up of 22 vaccinated gilts during 21 weeks post-vaccination (PV. The second one gathered the maternally derived antibodies (MDAs kinetics in piglets from three different farms up to 14 weeks of age. The peak of the PV serological response against PRRSv was reached 6.9 weeks PV on average with an average duration of antibodies persistence of 26.5 weeks. In the monitored cohort of piglets, the duration of passive immunity was found relatively short, with an average duration of 4.8 weeks. The level of PRRSv-MDAs was found correlated with the dams’ antibody titer at birth, and the antibody persistence was strongly related to the initial MDAs titers in piglets. These results evidenced the importance of PRRSv vaccination schedule in sows, to optimize the delivery of antibodies to suckling piglets. These estimates of the duration of active and passive immunity could be further used as input parameters of epidemiological models to analyze their impact on the persistence of PRRSv within farms.

  9. Estimating Parameters Related to the Lifespan of Passively Transferred and Vaccine-Induced Porcine Reproductive and Respiratory Syndrome Virus Type I Antibodies by Modeling Field Data.

    Science.gov (United States)

    Andraud, Mathieu; Fablet, Christelle; Renson, Patricia; Eono, Florent; Mahé, Sophie; Bourry, Olivier; Rose, Nicolas

    2018-01-01

    The outputs of epidemiological models are strongly related to the structure of the model and input parameters. The latter are defined by fitting theoretical concepts to actual data derived from field or experimental studies. However, some parameters may remain difficult to estimate and are subject to uncertainty or sensitivity analyses to determine their variation range and their global impact on model outcomes. As such, the evaluation of immunity duration is often a puzzling issue requiring long-term follow-up data that are, most of time, not available. The present analysis aims at characterizing the kinetics of antibodies against Porcine Reproductive and Respiratory Syndrome virus (PRRSv) from longitudinal data sets. The first data set consisted in the serological follow-up of 22 vaccinated gilts during 21 weeks post-vaccination (PV). The second one gathered the maternally derived antibodies (MDAs) kinetics in piglets from three different farms up to 14 weeks of age. The peak of the PV serological response against PRRSv was reached 6.9 weeks PV on average with an average duration of antibodies persistence of 26.5 weeks. In the monitored cohort of piglets, the duration of passive immunity was found relatively short, with an average duration of 4.8 weeks. The level of PRRSv-MDAs was found correlated with the dams' antibody titer at birth, and the antibody persistence was strongly related to the initial MDAs titers in piglets. These results evidenced the importance of PRRSv vaccination schedule in sows, to optimize the delivery of antibodies to suckling piglets. These estimates of the duration of active and passive immunity could be further used as input parameters of epidemiological models to analyze their impact on the persistence of PRRSv within farms.

  10. Estimating Parameters Related to the Lifespan of Passively Transferred and Vaccine-Induced Porcine Reproductive and Respiratory Syndrome Virus Type I Antibodies by Modeling Field Data

    Science.gov (United States)

    Andraud, Mathieu; Fablet, Christelle; Renson, Patricia; Eono, Florent; Mahé, Sophie; Bourry, Olivier; Rose, Nicolas

    2018-01-01

    The outputs of epidemiological models are strongly related to the structure of the model and input parameters. The latter are defined by fitting theoretical concepts to actual data derived from field or experimental studies. However, some parameters may remain difficult to estimate and are subject to uncertainty or sensitivity analyses to determine their variation range and their global impact on model outcomes. As such, the evaluation of immunity duration is often a puzzling issue requiring long-term follow-up data that are, most of time, not available. The present analysis aims at characterizing the kinetics of antibodies against Porcine Reproductive and Respiratory Syndrome virus (PRRSv) from longitudinal data sets. The first data set consisted in the serological follow-up of 22 vaccinated gilts during 21 weeks post-vaccination (PV). The second one gathered the maternally derived antibodies (MDAs) kinetics in piglets from three different farms up to 14 weeks of age. The peak of the PV serological response against PRRSv was reached 6.9 weeks PV on average with an average duration of antibodies persistence of 26.5 weeks. In the monitored cohort of piglets, the duration of passive immunity was found relatively short, with an average duration of 4.8 weeks. The level of PRRSv-MDAs was found correlated with the dams’ antibody titer at birth, and the antibody persistence was strongly related to the initial MDAs titers in piglets. These results evidenced the importance of PRRSv vaccination schedule in sows, to optimize the delivery of antibodies to suckling piglets. These estimates of the duration of active and passive immunity could be further used as input parameters of epidemiological models to analyze their impact on the persistence of PRRSv within farms. PMID:29435455

  11. A significant proportion of normal resting B cells are induced to secrete immunoglobulin through contact with anti-receptor antibody-activated helper T cells in clonal cultures

    DEFF Research Database (Denmark)

    Riedel, C; Owens, T; Nossal, G J

    1988-01-01

    This report describes single-cell techniques to address the nature of a cellular interaction in which activated T lymphocytes stimulate small resting B cells to develop into antibody-forming cell clones in the absence of any surface immunoglobulin ligand or an antigen bridge. The cloned T helper...... cell line E9.D4 was stimulated with the anti-V beta 8 antibody F23.1 bound to the plastic of Terasaki 10-ul culture wells. When an excess of T helper lymphocytes was used (1,000 X-irradiated or 600 unirradiated, stimulated E9.D4 cells), 10-25% of B cells responded by antibody formation as judged...... and B cells into proximity at the sulcus formed at the bottom edge of the culture wells. When T cell numbers were limiting, unirradiated T cells out-performed irradiated T cells. Some cell clones held for 7 days switched to IgG antibody production. E9.D4 supernatants were virtually ineffective...

  12. No evidence for a protective effect of naturally induced HPV antibodies on subsequent anogenital HPV infection in HIV-negative and HIV-infected MSM

    NARCIS (Netherlands)

    Mooij, Sofie H.; Landén, Olivia; van der Klis, Fiona R. M.; van der Sande, Marianne A. B.; de Melker, Hester E.; Coutinho, Roel A.; van Eeden, Arne; van Rooijen, Martijn S.; Meijer, Chris J. L. M.; Schim van der Loeff, Maarten F.

    2014-01-01

    To assess whether HPV serum antibodies detected after natural infection protect against subsequent anal or penile infection with the same HPV type in HIV-negative and HIV-infected men who have sex with men (MSM). MSM aged ≥18 years were recruited in Amsterdam, the Netherlands (2010-2011), and

  13. Influenza vaccination can induce new onset anticardiolipins but not β2-glycoprotein-I antibodies among patients with systemic lupus erythematosus

    Science.gov (United States)

    Vista, Evan S.; Crowe, Sherry R.; Thompson, Linda F.; Air, Gillian M.; Robertson, Julie M.; Guthridge, Joel M.; James, Judith A.

    2012-01-01

    Summary Background Antiphospholipid syndrome is characterized by autoantibodies against cardiolipins (aCL), lupus anticoagulant, and independent β2-glycoprotein (β2GPI). Controversy exists as to whether vaccination triggers the development of anti-phospholipid antibodies (aPL) in systemic lupus erythematosus (SLE) patients. Methods SLE patients (101) and matched controls (101) were enrolled from 2005 to 2009 and received seasonal influenza vaccinations. Sera were tested by ELISA for aCL at baseline, 2, 6, and 12 weeks after vaccination. Vaccine responses were ranked according to an overall anti-influenza antibody response index. Individuals with positive aCL were further tested for β2GPI antibodies. Results SLE patients and healthy controls developed new onset aCL post-vaccination (12/101 cases and 7/101 controls, OR 1.81, p=0.34). New onset moderate aCL are slightly enriched in African American SLE patients (5/36 cases; p=0.094). The optical density (OD) measurements for aCL reactivity in patients were significantly higher than baseline at 2 weeks (pvaccination. No new β2GPI antibodies were detected among patients with new aCL reactivity. Vaccine response was not different between patients with and without new onset aCL reactivity (p=0.43). Conclusions This study shows transient increases in aCL, but not anti-β2GPI responses, after influenza vaccination. PMID:22235049

  14. Influenza vaccination can induce new-onset anticardiolipins but not β2-glycoprotein-I antibodies among patients with systemic lupus erythematosus.

    Science.gov (United States)

    Vista, E S; Crowe, S R; Thompson, L F; Air, G M; Robertson, J M; Guthridge, J M; James, J A

    2012-02-01

    Antiphospholipid syndrome is characterized by autoantibodies against cardiolipins (aCL), lupus anticoagulant, and independent β2-glycoprotein (β2GPI). Controversy exists as to whether vaccination triggers the development of antiphospholipid antibodies (aPL) in patients with systemic lupus erythematosus (SLE). Patients with SLE (101) and matched controls (101) were enrolled from 2005-2009 and received seasonal influenza vaccinations. Sera were tested by ELISA for aCL at baseline, 2, 6, and 12 weeks after vaccination. Vaccine responses were ranked according to an overall anti-influenza antibody response index. Individuals with positive aCL were further tested for β2GPI antibodies. Patients with SLE and healthy controls can develop new-onset aCL post vaccination, although at rates which do not differ between patients and controls (12/101 cases and 7/101 controls, OR 1.81, p = 0.34). New-onset moderate aCL are slightly enriched in African American SLE patients (5/36 cases; p = 0.094). The optical density measurements for aCL reactivity in patients were significantly higher than baseline at 2 weeks (p vaccination. No new β2GPI antibodies were detected among patients with new aCL reactivity. Vaccine response was not different between patients with and without new-onset aCL reactivity (p = 0.43). This study shows transient increases in aCL, but not anti-β2GPI responses, after influenza vaccination.

  15. A significant proportion of normal resting B cells are induced to secrete immunoglobulin through contact with anti-receptor antibody-activated helper T cells in clonal cultures

    DEFF Research Database (Denmark)

    Riedel, C; Owens, T; Nossal, G J

    1988-01-01

    cell line E9.D4 was stimulated with the anti-V beta 8 antibody F23.1 bound to the plastic of Terasaki 10-ul culture wells. When an excess of T helper lymphocytes was used (1,000 X-irradiated or 600 unirradiated, stimulated E9.D4 cells), 10-25% of B cells responded by antibody formation as judged...... by an enzyme-linked immunosorbent assay performed after 5 days of culture. When one of a very small number of B cells were present, the rate-limiting step to antibody-forming cell formation was the number of T cells present. Far fewer T cells sufficed for stimulation when culture trays were tilted to force T...... and B cells into proximity at the sulcus formed at the bottom edge of the culture wells. When T cell numbers were limiting, unirradiated T cells out-performed irradiated T cells. Some cell clones held for 7 days switched to IgG antibody production. E9.D4 supernatants were virtually ineffective...

  16. The natural human IgM antibody PAT-SM6 induces apoptosis in primary human multiple myeloma cells by targeting heat shock protein GRP78.

    Directory of Open Access Journals (Sweden)

    Leo Rasche

    Full Text Available In contrast to other haematological malignancies, targeted immunotherapy has not entered standard treatment regimens for de novo or relapsed multiple myeloma (MM yet. While a number of IgG-formatted monoclonal antibodies are currently being evaluated in clinical trials in MM, our study aimed to investigate whether the fully human IgM monoclonal antibody PAT-SM6 that targets a tumour-specific variant of the heat shock protein GRP78 might be an attractive candidate for future immunotherapeutic approaches. We here show that GRP78 is stably and consistently expressed on the surface on tumour cells from patients with de novo, but also relapsed MM and that binding of PAT-SM6 to MM cells can specifically exert cytotoxic effects on malignant plasma cells, whereas non-malignant cells are not targeted. We demonstrate that the induction of apoptosis and, to a lesser extent, complement dependent cytotoxicity is the main mode of action of PAT-SM6, whereas antibody dependent cellular cytotoxicity does not appear to contribute to the cytotoxic properties of this antibody. Given the favourable safety profile of PAT-SM6 in monkeys, but also in a recent phase I trial in patients with malignant melanoma, our results form the basis for a planned phase I study in patients with relapsed MM.

  17. Anti-streptococcus IgM antibodies induce repetitive stereotyped movements: cell activation and co-localization with Fcα/μ receptors in the striatum and motor cortex.

    Science.gov (United States)

    Zhang, Danhui; Patel, Ankur; Zhu, Youhua; Siegel, Allan; Zalcman, Steven S

    2012-05-01

    Group A beta-hemolytic streptococcus (GABHS) infections are implicated in neuropsychiatric disorders associated with an increased expression of repetitive stereotyped movements. Anti-streptococcus IgG presumably cross-reacts with elements on basal ganglia cells, modifies their function, and triggers symptoms. IgM may play a unique role in precipitating behavioral disturbances since variations in cortico-striatal activity occur in temporal congruity with peak IgM titers during an orchestrated immune response. We discovered in Balb/c mice that single subcutaneous injections of mouse monoclonal IgM antibodies to streptococcus group A bacteria induce marked dose-dependent increases in repetitive stereotyped movements, including head bobbing, sniffing, and intense grooming. Effects were antibody- and antigen-specific: anti-streptococcus IgG stimulated ambulatory activity and vertical activity but not these stereotypies, while anti-KLH IgM reduced activity. We suggest that anti-streptococcus IgM and IgG play unique roles in provoking GABHS-related behavioral disturbances. Paralleling its stereotypy-inducing effects, anti-streptococcus IgM stimulated Fos-like immunoreactivity in regions linked to cortico-striatal projections involved in motor control, including subregions of the caudate, nucleus accumbens, and motor cortex. This is the first evidence that anti-streptococcus IgM antibodies induce in vivo functional changes in these structures. Moreover, there was a striking similarity in the distributions of anti-streptococcus IgM deposits and Fos-like immunoreactivity in these regions. Of further importance, Fcα/μ receptors, which bind IgM, were present- and co-localized with anti-streptococcus IgM in these structures. We suggest that anti-streptococcus IgM-induced alterations of cell activity reflect local actions of IgM that involve Fcα/μ receptors. These findings support the use of anti-streptococcus monoclonal antibody administration in Balb/c mice to model GABHS

  18. Inhibitory effect of BIBN4096BS, CGRP(8-37), a CGRP antibody and an RNA-Spiegelmer on CGRP induced vasodilatation in the perfused and non-perfused rat middle cerebral artery

    DEFF Research Database (Denmark)

    Edvinsson, L; Nilsson, E; Jansen-Olesen, I

    2007-01-01

    -37 and BIBN4096BS) on CGRP-induced relaxations in the rat middle cerebral artery (MCA). Furthermore, the role of the endothelial barrier has been studied. EXPERIMENTAL APPROACH: We used the luminally perfused MCA in an arteriograph, pressurized to 85 mm Hg and myograph studies of isolated ring segments...... of alphaCGRP was inhibited by luminal CGRP8-37 but not by luminal BIBN4096BS, CGRP antibody or NOX-C89. CONCLUSIONS AND IMPLICATIONS: alpha or betaCGRP acted on smooth muscle cell CGRP receptors in rat MCA and were effectively prevented from reaching these receptors by the endothelial barrier. The CGRP...

  19. Anti-Streptococcus IgM Antibodies Induce Repetitive Stereotyped Movements: Cell Activation and Co-Localization with Fcα/μ Receptors in the Striatum and Motor Cortex

    Science.gov (United States)

    Zhang, Danhui; Patel, Ankur; Zhu, Youhua; Siegel, Allan; Zalcman, Steven S.

    2012-01-01

    Group A beta-hemolytic streptococcus (GABHS) infections are implicated in neuropsychiatric disorders associated with an increased expression of repetitive stereotyped movements. Anti-streptococcus IgG presumably cross-reacts with elements on basal ganglia cells, modifies their function, and triggers symptoms. IgM may play a unique role in precipitating behavioral disturbances since variations in cortico-striatal activity occur in temporal congruity with peak IgM titers during an orchestrated immune response. We discovered in Balb/c mice that single subcutaneous injections of mouse monoclonal IgM antibodies to Streptococcus Group A bacteria induce marked dose-dependent increases in repetitive stereotyped movements, including head bobbing, sniffing, and intense grooming. Effects were antibody- and antigen-specific: anti-streptococcus IgG stimulated ambulatory activity and vertical activity but not these stereotypies, while anti-KLH IgM reduced activity. We suggest that anti-streptococcus IgM and IgG play unique roles in provoking GABHS-related behavioral disturbances. Paralleling its stereotypy-inducing effects, anti-streptococcus IgM stimulated Fos-like immunoreactivity in regions linked to cortico-striatal projections involved in motor control, including subregions of the caudate, nucleus accumbens, and motor cortex. This is the first evidence that anti-streptococcus IgM antibodies induce in vivo functional changes in these structures. Moreover, there was a striking similarity in the distributions of anti-streptococcus IgM deposits and Fos-like immunoreactivity in these regions. Of further importance, Fcα/μ receptors, which bind IgM, were present- and co-localized with anti-streptococcus IgM in these structures. We suggest that anti-streptococcus IgM-induced alterations of cell activity reflect local actions of IgM that involve Fcα/μ receptors. These findings support the use of anti-streptococcus monoclonal antibody administration in Balb/c mice to model GABHS

  20. Enhanced neutralization potency of botulinum neurotoxin antibodies using a red blood cell-targeting fusion protein.

    Directory of Open Access Journals (Sweden)

    Sharad P Adekar

    2011-03-01

    Full Text Available Botulinum neurotoxin (BoNT potently inhibits cholinergic signaling at the neuromuscular junction. The ideal countermeasures for BoNT exposure are monoclonal antibodies or BoNT antisera, which form BoNT-containing immune complexes that are rapidly cleared from the general circulation. Clearance of opsonized toxins may involve complement receptor-mediated immunoadherence to red blood cells (RBC in primates or to platelets in rodents. Methods of enhancing immunoadherence of BoNT-specific antibodies may increase their potency in vivo. We designed a novel fusion protein (FP to link biotinylated molecules to glycophorin A (GPA on the RBC surface. The FP consists of an scFv specific for murine GPA fused to streptavidin. FP:mAb:BoNT complexes bound specifically to the RBC surface in vitro. In a mouse model of BoNT neutralization, the FP increased the potency of single and double antibody combinations in BoNT neutralization. A combination of two antibodies with the FP gave complete neutralization of 5,000 LD50 BoNT in mice. Neutralization in vivo was dependent on biotinylation of both antibodies and correlated with a reduction of plasma BoNT levels. In a post-exposure model of intoxication, FP:mAb complexes gave complete protection from a lethal BoNT/A1 dose when administered within 2 hours of toxin exposure. In a pre-exposure prophylaxis model, mice were fully protected for 72 hours following administration of the FP:mAb complex. These results demonstrate that RBC-targeted immunoadherence through the FP is a potent enhancer of BoNT neutralization by antibodies in vivo.

  1. Immunization of chickens with an agonistic monoclonal anti-chicken CD40 antibody-hapten complex: rapid and robust IgG response induced by a single subcutaneous injection.

    Science.gov (United States)

    Chen, Chang-Hsin; Abi-Ghanem, Daad; Waghela, Suryakant D; Chou, Wen-Ko; Farnell, Morgan B; Mwangi, Waithaka; Berghman, Luc R

    2012-04-30

    Producing diagnostic antibodies in chicken egg yolk represents an alternate animal system that offers many advantages including high productivity at low cost. Despite being an excellent counterpart to mammalian antibodies, chicken IgG from yolk still represents an underused resource. The potential of agonistic monoclonal anti-CD40 antibodies (mAb) as a powerful immunological adjuvant has been demonstrated in mammals, but not in chickens. We recently reported an agonistic anti-chicken CD40 mAb (designated mAb 2C5) and showed that it may have potential as an immunological adjuvant. In this study, we examined the efficacy of targeting a short peptide to chicken CD40 [expressed by the antigen-presenting cells (APCs)] in enhancing an effective IgG response in chickens. For this purpose, an immune complex consisting of one streptavidin molecule, two directionally biotinylated mAb 2C5 molecules, and two biotinylated peptide molecules was produced. Chickens were immunized subcutaneously with doses of this complex ranging from 10 to 90 μg per injection once, and relative quantification of the peptide-specific IgG response showed that the mAb 2C5-based complex was able to elicit a strong IgG response as early as four days post-immunization. This demonstrates that CD40-targeting antigen to chicken APCs can significantly enhance antibody responses and induce immunoglobulin isotype-switching. This immunization strategy holds promise for rapid production of hapten-specific IgG in chickens. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Immunogenicity of anti-tumor necrosis factor antibodies - toward improved methods of anti-antibody measurement

    NARCIS (Netherlands)

    Aarden, Lucien; Ruuls, Sigrid R.; Wolbink, Gertjan

    2008-01-01

    To date, millions of people have been treated with therapeutic monoclonal antibodies (TmAbs) for various indications. It is becoming increasingly clear that TmAbs can be immunogenic, which may reduce efficacy or induce adverse effects. Over the years, the importance of antibody formation has been

  3. Prostaglandin F2alpha- and FAS-activating antibody-induced regression of the corpus luteum involves caspase-8 and is defective in caspase-3 deficient mice

    Directory of Open Access Journals (Sweden)

    Flavell Richard A

    2003-02-01

    Full Text Available Abstract We recently demonstrated that caspase-3 is important for apoptosis during spontaneous involution of the corpus luteum (CL. These studies tested if prostaglandin F2α (PGF2α or FAS regulated luteal regression, utilize a caspase-3 dependent pathway to execute luteal cell apoptosis, and if the two receptors work via independent or potentially shared intracellular signaling components/pathways to activate caspase-3. Wild-type (WT or caspase-3 deficient female mice, 25–26 days old, were given 10 IU equine chorionic gonadotropin (eCG intraperitoneally (IP followed by 10 IU human chorionic gonadotropin (hCG IP 46 h later to synchronize ovulation. The animals were then injected with IgG (2 micrograms, i.v., the FAS-activating antibody Jo2 (2 micrograms, i.v., or PGF2α (10 micrograms, i.p. at 24 or 48 h post-ovulation. Ovaries from each group were collected 8 h later for assessment of active caspase-3 enzyme and apoptosis (measured by the TUNEL assay in the CL. Regardless of genotype or treatment, CL in ovaries collected from mice injected 24 h after ovulation showed no evidence of active caspase-3 or apoptosis. However, PGF2α or Jo2 at 48 h post-ovulation and collected 8 h later induced caspase-3 activation in 13.2 ± 1.8% and 13.7 ± 2.2 % of the cells, respectively and resulted in 16.35 ± 0.7% (PGF2α and 14.3 ± 2.5% TUNEL-positive cells when compared to 1.48 ± 0.8% of cells CL in IgG treated controls. In contrast, CL in ovaries collected from caspase-3 deficient mice whether treated with PGF2α , Jo2, or control IgG at 48 h post-ovulation showed little evidence of active caspase-3 or apoptosis. CL of WT mice treated with Jo2 at 48 h post-ovulation had an 8-fold increase in the activity of caspase-8, an activator of caspase-3 that is coupled to the FAS death receptor. Somewhat unexpectedly, however, treatment of WT mice with PGF2α at 48 h post-ovulation resulted in a 22-fold increase in caspase-8 activity in the CL, despite the fact

  4. The role of complement receptor type 1 (CR1, CD35) in determining the cellular distribution of opsonized immune complexes between whole blood cells: kinetic analysis of the buffering capacity of erythrocytes

    DEFF Research Database (Denmark)

    Nielsen, C H; Matthiesen, S H; Lyng, I

    1997-01-01

    Erythrocytes (E) express complement receptor, type 1 (CR1, CD35), by which they bind opsonized immune complexes (IC) in competition with leucocytes expressing higher numbers of CR1 as well as other complement- and Fc-receptors. This may prevent inappropriate activation of phagocytic cells. We......-bound IC were associated with E from 1 to 5 min of incubation, decreasing to 12 +/- 13% after 40 min. Upon comparison of the IC-binding to leucocytes in whole blood with that of isolated leucocytes we found that E, despite their extensive early complex uptake, only reduced the IC......-deposition on polymorphonuclear leucocytes (PMN) by 61 +/- 26% after 30 seconds of incubation and 47 +/- 14% after 5 min. During the subsequent 10 min, this buffering capacity of E was essentially abolished E restricted the initial IC-binding to B cells by 73 +/- 19%, but from 3 min of incubation the presence of E promoted...

  5. In vivo T cell activation by anti-CD3 monoclonal antibody induces soluble TNF receptor release in mice. Effects of pentoxifylline, methylprednisolone, anti-TNF, and anti-IFN-gamma antibodies

    NARCIS (Netherlands)

    Bemelmans, M. H.; Abramowicz, D.; Gouma, D. J.; Goldman, M.; Buurman, W. A.

    1994-01-01

    Injection of anti-CD3 is accompanied by an increase in systemic TNF, a mediator of the physiologic changes induced by anti-CD3 injection. Various mechanisms have been reported to be responsible for TNF inactivation and clearance. Recently, it has become evident that circulating soluble TNFRs (P55

  6. In vivo T cell activation by anti-CD3 monoclonal antibody induces soluble TNF receptor release in mice. Effects of pentoxifylline, methylprednisolone, anti-TNF, and anti-IFN-gamma antibodies.

    NARCIS (Netherlands)

    Bemelmans, M.H.; Abramowicz, D.; Gouma, D.J.; Goldman, M.; Buurman, W.A.

    1994-01-01

    Injection of anti-CD3 is accompanied by an increase in systemic TNF, a mediator of the physiologic changes induced by anti-CD3 injection. Various mechanisms have been reported to be responsible for TNF inactivation and clearance. Recently, it has become evident that circulating soluble TNFRs (P55

  7. Association between functional antibody against Group B Streptococcus and maternal and infant colonization in a Gambian cohort.

    Science.gov (United States)

    Le Doare, Kirsty; Faal, Amadou; Jaiteh, Mustapha; Sarfo, Francess; Taylor, Stephen; Warburton, Fiona; Humphries, Holly; Birt, Jessica; Jarju, Sheikh; Darboe, Saffiatou; Clarke, Edward; Antonio, Martin; Foster-Nyarko, Ebenezer; Heath, Paul T; Gorringe, Andrew; Kampmann, Beate

    2017-05-19

    Vertical transmission of Group B Streptococcus (GBS) is a prerequisite for early-onset disease and a consequence of maternal GBS colonization. Disease protection is associated with maternally-derived anti-GBS antibody. Using a novel antibody-mediated C3b/iC3b deposition flow cytometry assay which correlates with opsonic killing we developed a model to assess the impact of maternally-derived functional anti-GBS antibody on infant GBS colonization from birth to day 60-89 of life. Rectovaginal swabs and cord blood (birth) and infant nasopharyngeal/rectal swabs (birth, day 6 and day 60-89) were obtained from 750 mother/infant pairs. Antibody-mediated C3b/iC3b deposition with cord and infant sera was measured by flow cytometry. We established that as maternally-derived anti-GBS functional antibody increases, infant colonization decreases at birth and up to three months of life, the critical time window for the development of GBS disease. Further, we observed a serotype (ST)-dependent threshold above which no infant was colonized at birth. Functional antibody above the upper 95th confidence interval for the geometric mean concentration was associated with absence of infant GBS colonization at birth for STII (p<0.001), STIII (p=0.01) and STV (p<0.001). Increased functional antibody was also associated with clearance of GBS between birth and day 60-89. Higher concentrations of maternally-derived antibody-mediated complement deposition are associated with a decreased risk of GBS colonization in infants up to day 60-89 of life. Our findings are of relevance to establish thresholds for protection following vaccination of pregnant women with future GBS vaccines. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  8. The Biological Function of Antibodies Induced by the RTS,S/AS01 Malaria Vaccine Candidate is Determined by Their Fine Specificity

    Science.gov (United States)

    2016-05-31

    malaria vaccine candidate is determined by their fine specificity Sidhartha Chaudhury1, Christian F. Ockenhouse2, Jason A. Regules3, Sheetij Dutta4...Anders Wallqvist1, Erik Jongert5, Norman C. Waters4, Franck Lemiale2 and Elke Bergmann‑Leitner4* Abstract Background: Recent vaccine studies have shown... vaccine candidate, RTS,S, have shown that circumsporozoite protein (CSP)‑specific antibodies and CD4+ T cell responses are associated with protection

  9. Anti-cocaine antibody and butyrylcholinesterase-derived cocaine hydrolase exert cooperative effects on cocaine pharmacokinetics and cocaine-induced locomotor activity in mice

    OpenAIRE

    Brimijoin, Stephen; Orson, Frank; Kosten, Tom; Kinsey, Berma; Shen, Xiao Yun; White, Sarah J.; Gao, Yang

    2012-01-01

    We are investigating treatments for cocaine abuse based on viral gene transfer of a cocaine hydrolase (CocH) derived from human butyrylcholinesterase, which can reduce cocaine-stimulated locomotion and cocaine-primed reinstatement of drug-seeking behavior in rats for many months. Here, in mice, we explored the possibility that anti-cocaine antibodies can complement the actions of CocH to reduce cocaine uptake in brain and block centrally-evoked locomotor stimulation. Direct injections of test...

  10. Vaccination of Koalas with a Recombinant Chlamydia pecorum Major Outer Membrane Protein Induces Antibodies of Different Specificity Compared to Those Following a Natural Live Infection

    Science.gov (United States)

    Kollipara, Avinash; Polkinghorne, Adam; Beagley, Kenneth W.; Timms, Peter

    2013-01-01

    Chlamydial infection in koalas is common across the east coast of Australia and causes significant morbidity, infertility and mortality. An effective vaccine to prevent the adverse consequences of chlamydial infections in koalas (particularly blindness and infertility in females) would provide an important management tool to prevent further population decline of this species. An important step towards developing a vaccine in koalas is to understand the host immune response to chlamydial infection. In this study, we used the Pepscan methodology to identify B cell epitopes across the Major Outer Membrane Protein (MOMP) of four C. pecorum strains/genotypes that are recognized, either following (a) natural live infection or (b) administration of a recombinant MOMP vaccine. Plasma antibodies from the koalas naturally infected with a C. pecorum G genotype strain recognised the epitopes located in the variable domain (VD) four of MOMP G and also VD4 of MOMP H. By comparison, plasma antibodies from an animal infected with a C. pecorum F genotype strain recognised epitopes in VD1, 2 and 4 of MOMP F, but not from other genotype MOMPs. When Chlamydia-free koalas were immunised with recombinant MOMP protein they produced antibodies not only against epitopes in the VDs but also in conserved domains of MOMP. Naturally infected koalas immunised with recombinant MOMP protein also produced antibodies against epitopes in the conserved domains. This work paves the way for further refinement of a MOMP-based Chlamydia vaccine that will offer wide cross-protection against the variety of chlamydial infections circulating in wild koala populations. PMID:24086379

  11. Vaccination of koalas with a recombinant Chlamydia pecorum major outer membrane protein induces antibodies of different specificity compared to those following a natural live infection.

    Directory of Open Access Journals (Sweden)

    Avinash Kollipara

    Full Text Available Chlamydial infection in koalas is common across the east coast of Australia and causes significant morbidity, infertility and mortality. An effective vaccine to prevent the adverse consequences of chlamydial infections in koalas (particularly blindness and infertility in females would provide an important management tool to prevent further population decline of this species. An important step towards developing a vaccine in koalas is to understand the host immune response to chlamydial infection. In this study, we used the Pepscan methodology to identify B cell epitopes across the Major Outer Membrane Protein (MOMP of four C. pecorum strains/genotypes that are recognized, either following (a natural live infection or (b administration of a recombinant MOMP vaccine. Plasma antibodies from the koalas naturally infected with a C. pecorum G genotype strain recognised the epitopes located in the variable domain (VD four of MOMP G and also VD4 of MOMP H. By comparison, plasma antibodies from an animal infected with a C. pecorum F genotype strain recognised epitopes in VD1, 2 and 4 of MOMP F, but not from other genotype MOMPs. When Chlamydia-free koalas were immunised with recombinant MOMP protein they produced antibodies not only against epitopes in the VDs but also in conserved domains of MOMP. Naturally infected koalas immunised with recombinant MOMP protein also produced antibodies against epitopes in the conserved domains. This work paves the way for further refinement of a MOMP-based Chlamydia vaccine that will offer wide cross-protection against the variety of chlamydial infections circulating in wild koala populations.

  12. Antigenic Peptides Capable of Inducing Specific Antibodies for Detection of the Major Alterations Found in Type 2B Von Willebrand Disease

    Directory of Open Access Journals (Sweden)

    Marina de Oliveira Paro

    2013-01-01

    Full Text Available Von Willebrand disease (VWD is an inherited hemorrhagic disorder promoted by either quantitative or qualitative defects of the von Willebrand factor (VWF. The disease represents the most common human coagulopathy afflicting 1.3% of the population. Qualitative defects are subdivided into four subtypes and classified according to the molecular dysfunction of the VWF. The differential diagnosis of the VWD is a difficult task, relying on a panel of tests aimed to assess the plasma levels and function of the VWF. Here, we propose biochemical approaches for the identification of structural variants of the VWF. A bioinformatic analysis was conducted to design seven peptides among which three were representatives of specific amino acid sequences belonging to normal VWF and four encompassed sequences found in the most common VWD subtype 2B. These peptides were used to immunize mice, after which, peptide-specific immunoglobulins were purified. This resulted in four Ig preparations capable of detecting alterations in the subtype 2B VWD plus additional three antibody fractions targeting the normal VWF. The panel of antibodies could serve many applications among them (1 assessment of VWF: antigen interaction, (2 VWF multimer analysis, and (3 production of monoclonal antibodies against VWF for therapeutic purposes as in thrombotic thrombocytopenic purpura.

  13. Antigenic Peptides Capable of Inducing Specific Antibodies for Detection of the Major Alterations Found in Type 2B Von Willebrand Disease

    Science.gov (United States)

    Paro, Marina de Oliveira; Ferreira, Cyntia Silva; Vieira, Fernanda Silva; de Santana, Marcos Aurélio; Namen-Lopes, Maria Sueli Silva; Leclercq, Sophie Yvette; Velloso-Rodrigues, Cibele; Guerra de Andrade, Milton Hércules

    2013-01-01

    Von Willebrand disease (VWD) is an inherited hemorrhagic disorder promoted by either quantitative or qualitative defects of the von Willebrand factor (VWF). The disease represents the most common human coagulopathy afflicting 1.3% of the population. Qualitative defects are subdivided into four subtypes and classified according to the molecular dysfunction of the VWF. The differential diagnosis of the VWD is a difficult task, relying on a panel of tests aimed to assess the plasma levels and function of the VWF. Here, we propose biochemical approaches for the identification of structural variants of the VWF. A bioinformatic analysis was conducted to design seven peptides among which three were representatives of specific amino acid sequences belonging to normal VWF and four encompassed sequences found in the most common VWD subtype 2B. These peptides were used to immunize mice, after which, peptide-specific immunoglobulins were purified. This resulted in four Ig preparations capable of detecting alterations in the subtype 2B VWD plus additional three antibody fractions targeting the normal VWF. The panel of antibodies could serve many applications among them (1) assessment of VWF: antigen interaction, (2) VWF multimer analysis, and (3) production of monoclonal antibodies against VWF for therapeutic purposes as in thrombotic thrombocytopenic purpura. PMID:23970904

  14. B cell and antibody responses in mice induced by a putative cell surface peptidase of Pneumocystis murina protect against experimental infection.

    Science.gov (United States)

    Ruan, Sanbao; Cai, Yang; Ramsay, Alistair J; Welsh, David A; Norris, Karen; Shellito, Judd E

    2017-01-23

    Pneumocystis pneumonia is a major cause of morbidity and mortality in HIV-infected subjects, cancer patients undergoing chemotherapy and solid organ transplant recipients. No vaccine is currently available. By chemical labeling coupled with proteomic approach, we have identified a putative surface protein (SPD1, Broad Institute gene accession number PNEG_01848) derived from single suspended P. murina cysts. SPD1 was expressed in an insect cell line and tested for vaccine development. Mice were immunized with SPD1 plus adjuvant MF-59 by subcutaneous injection. Three weeks after the last immunization, CD4+ cells were depleted with anti-CD4 antibody GK1.5. The mice were then challenged with 2×10 5 Pneumocystis organisms. Mice were sacrificed at 4 and 6weeks after PC challenge. Spleen/lung cells and serum were harvested. B cells and memory B cells were assessed via flow cytometry. Specific Pneumocystis IgG antibody was measured by ELISA before and after challenge. Infection burden was measured as real-time PCR for P. murina rRNA. Normal mice infected with Pneumocystis mounted a serum IgG antibody response to SPD1. Serum from rhesus macaques exposed to Pneumocystis showed a similar serum IgG response to purified SPD1. SPD1 immunization increased B cell and memory B cell absolute cell counts in CD4-depleted Balb/c mice post Pneumocystis challenge in spleen and lung. Immunization with SPD1 significantly increased specific Pneumocystis IgG antibody production before and after challenge. Mice immunized with SPD1 showed significantly decreased P. murina copy number compared with mice that did not receive SPD1 at 6weeks after challenge. Immunization with SPD1 provides protective efficacy against P. murina infection. SPD1 protection against Pneumocystis challenge is associated with enhanced memory B cell production and higher anti-Pneumocystis IgG antibody production. SPD1 is a potential vaccine candidate to prevent or treat pulmonary infection with Pneumocystis. Copyright

  15. Antiphospholipid antibody: laboratory, pathogenesis and clinical manifestations

    Directory of Open Access Journals (Sweden)

    T. Ziglioli

    2011-06-01

    Full Text Available Antiphospholipid antibodies (aPL represent a heterogeneous group of antibodies that recognize various antigenic targets including beta2 glycoprotein I (β2GPI, prothrombin (PT, activated protein C, tissue plasminogen activator, plasmin and annexin A2. The most commonly used tests to detect aPL are: lupus anticoagulant (LAC, a functional coagulation assay, anticardiolipin antibody (aCL and anti-β2GPI antibody (anti-β2GPI, which are enzyme-linked immunoassay (ELISA. Clinically aPL are associated with thrombosis and/or with pregnancy morbidity. Apparently aPL alone are unable to induce thrombotic manifestations, but they increase the risk of vascular events that can occur in the presence of another thrombophilic condition; on the other hand obstetrical manifestations were shown to be associated not only to thrombosis but mainly to a direct antibody effect on the trophoblast.

  16. A novel H6N1 virus-like particle vaccine induces long-lasting cross-clade antibody immunity against human and avian H6N1 viruses.

    Science.gov (United States)

    Yang, Ji-Rong; Chen, Chih-Yuan; Kuo, Chuan-Yi; Cheng, Chieh-Yu; Lee, Min-Shiuh; Cheng, Ming-Chu; Yang, Yu-Chih; Wu, Chia-Ying; Wu, Ho-Sheng; Liu, Ming-Tsan; Hsiao, Pei-Wen

    2016-02-01

    Avian influenza A(H6N1) virus is one of the most common viruses isolated from migrating birds and domestic poultry in many countries. The first and only known case of human infection by H6N1 virus in the world was reported in Taiwan in 2013. This led to concern that H6N1 virus may cause a threat to public health. In this study, we engineered a recombinant H6N1 virus-like particle (VLP) and investigated its vaccine effectiveness compared to the traditional egg-based whole inactivated virus (WIV) vaccine. The H6N1-VLPs exhibited similar morphology and functional characteristics to influenza viruses. Prime-boost intramuscular immunization in mice with unadjuvanted H6N1-VLPs were highly immunogenic and induced long-lasting antibody immunity. The functional activity of the VLP-elicited IgG antibodies was proved by in vitro seroprotective hemagglutination inhibition and microneutralization titers against the homologous human H6N1 virus, as well as in vivo viral challenge analyses which showed H6N1-VLP immunization significantly reduced viral load in the lung, and protected against human H6N1 virus infection. Of particular note, the H6N1-VLPs but not the H6N1-WIVs were able to confer cross-reactive humoral immunity; antibodies induced by H6N1-VLP vaccine robustly inhibited the hemagglutination activities and in vitro replication of distantly-related heterologous avian H6N1 viruses. Furthermore, the H6N1-VLPs were found to elicit significantly greater anti-HA2 antibody responses in immunized mice than H6N1-WIVs. Collectively, we demonstrated for the first time a novel H6N1-VLP vaccine that effectively provides broadly protective immunity against both human and avian H6N1 viruses. These results, which uncover the underlying mechanisms for induction of wide-range immunity against influenza viruses, may be useful for future influenza vaccine development. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Meningococcal serogroup C immunogenicity, antibody persistence and memory B-cells induced by the monovalent meningococcal serogroup C versus quadrivalent meningococcal serogroup ACWY conjugate booster vaccine: A randomized controlled trial.

    Science.gov (United States)

    van Ravenhorst, Mariëtte B; van der Klis, Fiona R M; van Rooijen, Debbie M; Knol, Mirjam J; Stoof, Susanne P; Sanders, Elisabeth A M; Berbers, Guy A M

    2017-08-24

    Adolescents are considered the key transmitters of meningococci in the population. Meningococcal serogroup C (MenC) antibody levels wane rapidly after MenC conjugate vaccination in young children, leaving adolescents with low antibody levels. In this study, we compared MenC immune responses after booster vaccination in adolescence with either tetanus toxoid conjugated MenC (MenC-TT) or MenACWY (MenACWY-TT) vaccine, and aimed to establish an optimal age for this booster. Healthy 10-, 12-, and 15-year-olds, who received a single dose of MenC-TT vaccine in early childhood, were randomized to receive MenC-TT or MenACWY-TT vaccine. MenC serum bactericidal antibody (rSBA) titers, MenC polysaccharide (PS) specific IgG, IgG1 and IgG2 and MenC-specific IgG and IgA memory B-cells were determined before, one month and one year after the booster. Non-inferiority was tested by comparing geometric mean titers (GMTs) between vaccinees at one year. Of 501 participants, 464 (92.6%) were included in the 'according to protocol' cohort analysis. At one month, all participants developed high MenC rSBA titers (>24,000 in all groups) and MenC-PS-specific IgG levels. Non-inferiority was not demonstrated one year after the booster with higher MenC GMTs after the monovalent vaccine, but 462/464 (99.6%) participants maintained protective MenC rSBA titers. IgG levels mainly consisted of IgG1, but similar levels of increase were observed for IgG1 and IgG2. Both vaccines induced a clear increase in the number of circulating MenC-PS specific IgG and IgA memory B-cells. Between one month and one year, the highest antibody decay rate was observed in the 10-year-olds. Both MenC-TT and MenACWY-TT vaccines induced robust protective MenC immune responses after the booster vaccination, although non-inferiority could not be demonstrated for the MenACWY-TT vaccine after one year. Our results underline the importance of optimal timing of a meningococcal booster vaccination to protect against MenC disease

  18. Acetylcholine receptor antibody

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003576.htm Acetylcholine receptor antibody To use the sharing features on this page, please enable JavaScript. Acetylcholine receptor antibody is a protein found in the blood ...

  19. Platelet antibodies blood test

    Science.gov (United States)

    This blood test shows if you have antibodies against platelets in your blood. Platelets are a part of the blood ... Chernecky CC, Berger BJ. Platelet antibody - blood. In: Chernecky ... caused by platelet destruction, hypersplenism, or hemodilution. ...

  20. A single point in protein trafficking by Plasmodium falciparum determines the expression of major antigens on the surface of infected erythrocytes targeted by human antibodies.

    Science.gov (United States)

    Chan, Jo-Anne; Howell, Katherine B; Langer, Christine; Maier, Alexander G; Hasang, Wina; Rogerson, Stephen J; Petter, Michaela; Chesson, Joanne; Stanisic, Danielle I; Duffy, Michael F; Cooke, Brian M; Siba, Peter M; Mueller, Ivo; Bull, Peter C; Marsh, Kevin; Fowkes, Freya J I; Beeson, James G

    2016-11-01

    Antibodies to blood-stage antigens of Plasmodium falciparum play a pivotal role in human immunity to malaria. During parasite development, multiple proteins are trafficked from the intracellular parasite to the surface of P. falciparum-infected erythrocytes (IEs). However, the relative importance of different proteins as targets of acquired antibodies, and key pathways involved in trafficking major antigens remain to be clearly defined. We quantified antibodies to surface antigens among children, adults, and pregnant women from different malaria-exposed regions. We quantified the importance of antigens as antibody targets using genetically engineered P. falciparum with modified surface antigen expression. Genetic deletion of the trafficking protein skeleton-binding protein-1 (SBP1), which is involved in trafficking the surface antigen PfEMP1, led to a dramatic reduction in antibody recognition of IEs and the ability of human antibodies to promote opsonic phagocytosis of IEs, a key mechanism of parasite clearance. The great majority of antibody epitopes on the IE surface were SBP1-dependent. This was demonstrated using parasite isolates with different genetic or phenotypic backgrounds, and among antibodies from children, adults, and pregnant women in different populations. Comparisons of antibody reactivity to parasite isolates with SBP1 deletion or inhibited PfEMP1 expression suggest that PfEMP1 is the dominant target of acquired human antibodies, and that other P. falciparum IE surface proteins are minor targets. These results establish SBP1 as part of a critical pathway for the trafficking of major surface antigens targeted by human immunity, and have key implications for vaccine development, and quantifying immunity in populations.

  1. HIV-1 specific antibody titers and neutralization among chronically infected patients on long-term suppressive antiretroviral therapy (ART: a cross-sectional study.

    Directory of Open Access Journals (Sweden)

    Johannes S Gach

    Full Text Available The majority of potent and broadly neutralizing antibodies against HIV-1 have been isolated from untreated patients with acute or chronic infection. To assess the extent of HIV-1 specific antibody response and neutralization after many years of virologic suppression from potent combination ART, we examined antibody binding titers and neutralization of 51 patients with chronic HIV-1 infection on suppressive ART for at least three years. In this cross-sectional analysis, we found high antibody titers against gp120, gp41, and the membrane proximal external region (MPER in 59%, 43%, and 27% of patients, respectively. We observed significantly higher endpoint binding titers for gp120 and gp41 for patients with >10 compared to ≤ 10 years of detectable HIV RNA. Additionally, we observed higher median gp120 and gp41 antibody titers in patients with HIV RNA 10 years of detectable HIV RNA (8/20 [40.0%] versus 3/31 [9.7%] for ≤ 10 years, p = 0.02 and a trend toward greater neutralization in patients with ≤ 5 years of HIV RNA 5 years, p = 0.08. All patients with neutralizing activity mediated successful phagocytosis of VLPs by THP-1 cells after antibody opsonization. Our findings of highly specific antibodies to several structural epitopes of HIV-1 with antibody effector functions and neutralizing activity after long-term suppressive ART, suggest continuous antigenic stimulation and evolution of HIV-specific antibody response occurs before and after suppression with ART. These patients, particularly those with slower HIV progression and more time with detectable viremia prior to initiation of suppressive ART, are a promising population to identify and further study functional antibodies against HIV-1.

  2. Dynamics of interaction between complement-fixing antibody/dsDNA immune complexes and erythrocytes. In vitro studies and potential general applications to clinical immune complex testing

    International Nuclear Information System (INIS)

    Taylor, R.P.; Horgan, C.; Hooper, M.; Burge, J.

    1985-01-01

    Soluble antibody/ 3 H-double-stranded PM2 DNA (dsDNA) immune complexes were briefly opsonized with complement and then allowed to bind to human erythrocytes (via complement receptors). The cells were washed and subsequently a volume of autologous blood in a variety of media was added, and the release of the bound immune complexes from the erythrocytes was studied as a function of temperature and time. After 1-2 h, the majority of the bound immune complexes were not released into the serum during blood clotting at either 37 degrees C or room temperature, but there was a considerably greater release of the immune complexes into the plasma of blood that was anticoagulated with EDTA. Similar results were obtained using various conditions of opsonization and also using complexes that contained lower molecular weight dsDNA. Thus, the kinetics of release of these antibody/dsDNA immune complexes differed substantially from the kinetics of release of antibody/bovine serum albumin complexes that was reported by others. Studies using the solution phase C1q immune complex binding assay confirmed that in approximately half of the SLE samples that were positive for immune complexes, there was a significantly higher level of detectable immune complexes in plasma vs. serum. Freshly drawn erythrocytes from some SLE patients exhibiting this plasma/serum discrepancy had IgG antigen on their surface that was released by incubation in EDTA plasma. Thus, the higher levels of immune complexes observed in EDTA plasma vs. serum using the C1q assay may often reflect the existence of immune complexes circulating in vivo bound to erythrocytes

  3. Poor Long-Term Efficacy of Prevnar-13 in Sickle Cell Disease Mice Is Associated with an Inability to Sustain Pneumococcal-Specific Antibody Titers.

    Directory of Open Access Journals (Sweden)

    Steven M Szczepanek

    Full Text Available One of the most common causes of morbidity and mortality in children with sickle cell disease (SCD is infection with the pneumococcal bacterium (Streptococcus pneumoniae. Unfortunately, the polysaccharide-conjugate vaccine appears to be less effective in individuals with SCD when compared to the general population. We sought to better understand the relative efficacy of pneumococcal vaccination in a SCD mouse challenge model.Transgenic control and SCD mice were monitored for mortality after intranasal pneumococcal infection or pneumococcal vaccination with Prevnar-13 and type-matched challenge. Anti-pneumococcal antibody titers were measured by ELISA and opsonophagocytosis was measured in vitro.Mortality after pneumococcal infection was similar between control and SCD mice. However, after three intramuscular polysaccharide-conjugate vaccinations, all control mice were protected following high-dose intranasal infection, whereas 60% of SCD mice died. Anti-pneumococcal antibody titers showed initial IgG and IgM responses in both groups, but waning titers were observed in the SCD group, even after boosting. When functionally assayed in vitro, serum from SCD mice 13 weeks after a second booster shot maintained little to no ability to opsonize pneumococci, while serum from control mice sustained a significantly higher capacity opsonization. Thus, it appears that SCD mice do not maintain antibody responses to pneumococcal polysaccharides after Prevnar-13 vaccination, thereby leaving them susceptible to mortality after type-matched infection.Our results emphasize the need to better understand the correlates of immune protection in SCD so that pneumococcal vaccines can be improved and mortality reduced in this susceptible population.

  4. Immunization with gingipain A hemagglutinin domain of Porphyromonas gingivalis induces IgM antibodies binding to malondialdehyde-acetaldehyde modified low-density lipoprotein.

    Directory of Open Access Journals (Sweden)

    Mikael Kyrklund

    Full Text Available Treatment of periodontitis has beneficial effects on systemic inflammation markers that relate to progression of atherosclerosis. We aimed to investigate whether immunization with A hemagglutinin domain (Rgp44 of Porphyromonas gingivalis (Pg, a major etiologic agent of periodontitis, would lead to an antibody response cross-reacting with oxidized low-density lipoprotein (OxLDL and how it would affect the progression of atherosclerosis in low-density lipoprotein receptor-deficient (LDLR-/- mice. The data revealed a prominent IgM but not IgG response to malondialdehyde-acetaldehyde modified LDL (MAA-LDL after Rgp44 and Pg immunizations, implying that Rgp44/Pg and MAA adducts may share cross-reactive epitopes that prompt IgM antibody production and consequently confer atheroprotection. A significant negative association was observed between atherosclerotic lesion and plasma IgA to Rgp44 in Rgp44 immunized mice, supporting further the anti-atherogenic effect of Rgp44 immunization. Plasma IgA levels to Rgp44 and to Pg in both Rgp44- and Pg-immunized mice were significantly higher than those in saline control, suggesting that IgA to Rgp44 could be a surrogate marker of immunization in Pg-immunized mice. Distinct antibody responses in plasma IgA levels to MAA-LDL, to Pg lipopolysaccharides (Pg-LPS, and to phosphocholine (PCho were observed after Rgp44 and Pg immunizations, indicating that different immunogenic components between Rpg44 and Pg may behave differently in regard of their roles in the development of atherosclerosis. Immunization with Rgp44 also displayed atheroprotective features in modulation of plaque size through association with plasma levels of IL-1α whereas whole Pg bacteria achieved through regulation of anti-inflammatory cytokine levels of IL-5 and IL-10. The present study may contribute to refining therapeutic approaches aiming to modulate immune responses and inflammatory/anti-inflammatory processes in atherosclerosis.

  5. Cell-induced potentiation of the plasminogen activation system is abolished by a monoclonal antibody that recognizes the NH2-terminal domain of the urokinase receptor

    DEFF Research Database (Denmark)

    Rønne, E; Behrendt, N; Ellis, V

    1991-01-01

    -u-PA and plasminogen with U937 cells. This antibody, which is also the only one to completely inhibit the binding of DFP-inactivated [125I]-u-PA to U937 cells, is directed against the u-PA binding NH2-terminal domain of u-PAR, a well-defined fragment formed by limited chymotrypsin digestion of purified u......-PAR, demonstrating the functional independence of the u-PA binding domain as well as the critical role of u-PAR in the assembly of the cell-surface plasminogen activation system....

  6. Effect of ingested human antibodies induced by RTS, S/AS01 malaria vaccination in children on Plasmodium falciparum oocyst formation and sporogony in mosquitoes

    DEFF Research Database (Denmark)

    Miura, Kazutoyo; Jongert, Erik; Deng, Bingbing

    2014-01-01

    falciparum CS protein, but the ability of serum from vaccinated individuals to inhibit sporogony in mosquitoes has not been evaluated. METHODS: Previously a double-blind, randomized trial of RTS,S/AS01 vaccine, as compared with rabies vaccine, in five- to 17-month old children in Tanzania was conducted....... In this study, polyclonal human antibodies were purified from the pools of sera taken one month after the third vaccination. IgGs were purified from four pools of sera from 25 RTS,S/AS01 vaccinated children each, and two pools of sera from 25 children vaccinated with rabies vaccine each. The ability...

  7. Packaging and Prefusion Stabilization Separately and Additively Increase the Quantity and Quality of Respiratory Syncytial Virus (RSV)-Neutralizing Antibodies Induced by an RSV Fusion Protein Expressed by a Parainfluenza Virus Vector.

    Science.gov (United States)

    Liang, Bo; Ngwuta, Joan O; Herbert, Richard; Swerczek, Joanna; Dorward, David W; Amaro-Carambot, Emerito; Mackow, Natalie; Kabatova, Barbora; Lingemann, Matthias; Surman, Sonja; Yang, Lijuan; Chen, Man; Moin, Syed M; Kumar, Azad; McLellan, Jason S; Kwong, Peter D; Graham, Barney S; Schaap-Nutt, Anne; Collins, Peter L; Munir, Shirin

    2016-11-01

    Human respiratory syncytial virus (RSV) and human parainfluenza virus type 3 (HPIV3) are major pediatric respiratory pathogens that lack vaccines. A chimeric bovine/human PIV3 (rB/HPIV3) virus expressing the unmodified, wild-type (wt) RSV fusion (F) protein from an added gene was previously evaluated in seronegative children as a bivalent intranasal RSV/HPIV3 vaccine, and it was well tolerated but insufficiently immunogenic for RSV F. We recently showed that rB/HPIV3 expressing a partially stabilized prefusion form (pre-F) of RSV F efficiently induced "high-quality" RSV-neutralizing antibodies, defined as antibodies that neutralize RSV in vitro without added complement (B. Liang et al., J Virol 89:9499-9510, 2015, doi:10.1128/JVI.01373-15). In the present study, we modified RSV F by replacing its cytoplasmic tail (CT) domain or its CT and transmembrane (TM) domains (TMCT) with counterparts from BPIV3 F, with or without pre-F stabilization. This resulted in RSV F being packaged in the rB/HPIV3 particle with an efficiency similar to that of RSV particles. Enhanced packaging was substantially attenuating in hamsters (10- to 100-fold) and rhesus monkeys (100- to 1,000-fold). Nonetheless, TMCT-directed packaging substantially increased the titers of high-quality RSV-neutralizing serum antibodies in hamsters. In rhesus monkeys, a strongly additive immunogenic effect of packaging and pre-F stabilization was observed, as demonstrated by 8- and 30-fold increases of RSV-neutralizing serum antibody titers in the presence and absence of added complement, respectively, compared to pre-F stabilization alone. Analysis of vaccine-induced F-specific antibodies by binding assays indicated that packaging conferred substantial stabilization of RSV F in the pre-F conformation. This provides an improved version of this well-tolerated RSV/HPIV3 vaccine candidate, with potently improved immunogenicity, which can be returned to clinical trials. Human respiratory syncytial virus (RSV) and

  8. Antibodies against a Synthetic Peptide of SagA Neutralize the Cytolytic Activity of Streptolysin S from Group A Streptococci†

    Science.gov (United States)

    Dale, James B.; Chiang, Edna Y.; Hasty, David L.; Courtney, Harry S.

    2002-01-01

    Virtually all group A streptococci (GAS) produce streptolysin S (SLS), a cytolytic toxin that is responsible for the beta-hemolysis surrounding colonies of the organisms grown on blood agar. SLS is an important virulence determinant of GAS, and recent studies have identified a nine-gene locus that is responsible for synthesis and transport of the toxin. SLS is not immunogenic; thus, no neutralizing antibodies are evoked during the course of natural infection. In the present study, we show that a synthetic peptide containing amino acid residues 10 to 30 of the putative SLS (SagA) propeptide [SLS(10-30)] coupled to keyhole limpet hemocyanin evoked antibodies in rabbits that completely neutralized the hemolytic activity of the toxin in vitro. Inhibition of hemolysis was reversed by preincubation of the immune serum with soluble, unconjugated peptide, indicating the specificity of the antibodies. In addition, antibodies that were affinity purified over an SLS(10-30) peptide column completely inhibited SLS-mediated hemolysis. The SLS(10-30) antisera did not opsonize group A streptococci; however, when combined with type-specific M protein antisera, the SLS antibodies significantly enhanced phagocytosis mediated by M protein antibodies. Thus, we have shown for the first time that it is possible to raise neutralizing antibodies against one of the most potent bacterial cytolytic toxins known. Our data also provide convincing evidence that the sagA gene actually encodes the SLS peptide of GAS. The synthetic peptide may prove to be an important component of vaccines designed to prevent GAS infections. PMID:11895983

  9. A novel trivalent HPV 16/18/58 vaccine with anti-HPV 16 and 18 neutralizing antibody responses comparable to those induced by the Gardasil quadrivalent vaccine in rhesus macaque model

    Directory of Open Access Journals (Sweden)

    Fei Yin

    2017-06-01

    Full Text Available Persistent infection with human papillomavirus (HPV is a key factor in the development of precancerous lesions and invasive cervical cancer. Prophylactic vaccines to immunize against HPV are an effective approach to reducing HPV related disease burden. In this study, we investigated the immunogenicity and dosage effect of a trivalent HPV 16/18/58 vaccine (3vHPV produced in Escherichia coli (E.coli, with Gardasil quadrivalent vaccine (4vHPV, Merck & Co. as a positive control. Sera collected from rhesus macaques vaccinated with three dosage formulations of 3vHPV (termed low-, mid-, and high-dosage formulations, respectively, and the 4vHPV vaccine were analyzed by both Pseudovirus-Based Neutralization Assay (PBNA and Enzyme-Linked Immunosorbent Assay (ELISA. Strong immune responses against HPV 16/18/58 were successfully elicited, and dosage-dependence was observed, with likely occurrence of immune interference between different L1-VLP antigens. HPV 16/18 specific neutralizing antibody (nAb and total immunoglobulin G (IgG antibody responses in rhesus macaques receiving 3vHPV at the three dosages tested were generally non-inferior to those observed in rhesus macaques receiving 4vHPV throughout the study period. Particularly, HPV 18 nAb titers induced by the mid-dosage formulation that contained the same amounts of HPV 16/18 L1-VLPs as Gardasil 4vHPV were between 7.3 to 12.7-fold higher compared to the positive control arm from weeks 24–64. The durability of antibody responses specific to HPV 16/18 elicited by 3vHPV vaccines was also shown to be non-inferior to that associated with Gardasil 4vHPV. Keywords: Human papillomavirus, HPV 16/18/58, GMTs, Trivalent, Immunogenicity

  10. The presence of anti-thyroglobulin (TgAb) and/or anti-thyroperoxidase antibodies (TPOAb) does not exclude the diagnosis of type 2 amiodarone-induced thyrotoxicosis.

    Science.gov (United States)

    Tomisti, L; Urbani, C; Rossi, G; Latrofa, F; Sardella, C; Manetti, L; Lupi, I; Marcocci, C; Bartalena, L; Curzio, O; Martino, E; Bogazzi, F

    2016-05-01

    It is widely accepted that type 2 amiodarone-induced thyrotoxicosis (AIT) generally occurs in patients with a normal thyroid gland without signs of thyroid autoimmunity. However, it is currently unknown if the presence of anti-thyroglobulin (TgAb) and/or anti-thyroperoxidase antibodies (TPOAb) in AIT patients without other signs of an underlying thyroid disease may impair the response to glucocorticoid therapy. We performed a pilot retrospective cohort study with matched-subject design and an equivalence hypothesis, comparing the response to glucocorticoid therapy between 20 AIT patients with a normal thyroid gland, low radioiodine uptake, undetectable TSH receptor antibodies and positive TgAb and/or TPOAb (Ab+ group), and 40 patients with the same features and absent thyroid antibodies (Ab- group). The mean cure time was 54 ± 68 days in the Ab+ group and 55 ± 49 days in the Ab- group (p = 0.63). The equivalence test revealed an equivalent cure rate after 60, 90 and 180 days (p = 0.67, 0.88 and 0.278, respectively). The occurrence of permanent hypothyroidism was higher in the Ab+ group than in the Ab- group (26.3 vs 5.13 %, p = 0.032). The presence of TgAb and/or TPOAb does not affect the response to glucocorticoid therapy, suggesting that the patients with features of destructive form of AIT should be considered as having a type 2 AIT irrespective of the presence of TGAb or TPOAb. These patients have a higher risk of developing hypothyroidism after the resolution of thyrotoxicosis and should be monitored accordingly.

  11. Monoclonal antibodies and cancer

    International Nuclear Information System (INIS)

    Haisma, H.J.

    1987-01-01

    The usefulness of radiolabeled monoclonal antibodies for imaging and treatment of human (ovarian) cancer was investigated. A review of tumor imaging with monoclonal antibodies is presented. Special attention is given to factors that influence the localization of the antibodies in tumors, isotope choice and methods of radiolabeling of the monoclonal antibodies. Two monoclonal antibodies, OC125 and OV-TL3, with high specificity for human epithelial ovarian cancer are characterized. A simple radio-iodination technique was developed for clinical application of the monoclonal antibodies. The behavior of monoclonal antibodies in human tumor xenograft systems and in man are described. Imaging of tumors is complicated because of high background levels of radioactivity in other sites than the tumor, especially in the bloodpool. A technique was developed to improve imaging of human tumor xenographs in nude mice, using subtraction of a specific and a non-specific antibody, radiolabeled with 111 In, 67 Ga and 131 I. To investigate the capability of the two monoclonal antibodies, to specifically localize in human ovarian carcinomas, distribution studies in mice bearing human ovarian carcinoma xenografts were performed. One of the antibodies, OC125, was used for distribution studies in ovarian cancer patients. OC125 was used because of availability and approval to use this antibody in patients. The same antibody was used to investigate the usefulness of radioimmunoimaging in ovarian cancer patients. The interaction of injected radiolabeled antibody OC125 with circulating antigen and an assay to measure the antibody response in ovarian cancer patients after injection of the antibody is described. 265 refs.; 30 figs.; 19 tabs

  12. Combination with a defucosylated anti-HM1.24 monoclonal antibody plus lenalidomide induces marked ADCC against myeloma cells and their progenitors.

    Directory of Open Access Journals (Sweden)

    Takeshi Harada

    Full Text Available The immunomodulatory drug lenalidomide (Len has drawn attention to potentiate antibody-dependent cellular cytotoxicity (ADCC-mediated immunotherapies. We developed the defucosylated version (YB-AHM of humanized monoclonal antibody against HM1.24 (CD317 overexpressed in multiple myeloma (MM cells. In this study, we evaluated ADCC by YB-AHM and Len in combination against MM cells and their progenitors. YB-AHM was able to selectively kill via ADCC MM cells in bone marrow samples from patients with MM with low effector/target ratios, which was further enhanced by treatment with Len. Interestingly, Len also up-regulated HM1.24 expression on MM cells in an effector-dependent manner. HM1.24 was found to be highly expressed in a drug-resistant clonogenic "side population" in MM cells; and this combinatory treatment successfully reduced SP fractions in RPMI 8226 and KMS-11 cells in the presence of effector cells, and suppressed a clonogenic potential of MM cells in colony-forming assays. Collectively, the present study suggests that YB-AHM and Len in combination may become an effective therapeutic strategy in MM, warranting further study to target drug-resistant MM clonogenic cells.

  13. Broad-spectrum inhibition of HIV-1 by a monoclonal antibody directed against a gp120-induced epitope of CD4.

    Directory of Open Access Journals (Sweden)

    Samuele E Burastero

    Full Text Available To penetrate susceptible cells, HIV-1 sequentially interacts with two highly conserved cellular receptors, CD4 and a chemokine receptor like CCR5 or CXCR4. Monoclonal antibodies (MAbs directed against such receptors are currently under clinical investigation as potential preventive or therapeutic agents. We immunized Balb/c mice with molecular complexes of the native, trimeric HIV-1 envelope (Env bound to a soluble form of the human CD4 receptor. Sera from immunized mice were found to contain gp120-CD4 complex-enhanced antibodies and showed broad-spectrum HIV-1-inhibitory activity. A proportion of MAbs derived from these mice preferentially recognized complex-enhanced epitopes. In particular, a CD4-specific MAb designated DB81 (IgG1Κ was found to preferentially bind to a complex-enhanced epitope on the D2 domain of human CD4. MAb DB81 also recognized chimpanzee CD4, but not baboon or macaque CD4, which exhibit sequence divergence in the D2 domain. Functionally, MAb DB81 displayed broad HIV-1-inhibitory activity, but it did not exert suppressive effects on T-cell activation in vitro. The variable regions of the heavy and light chains of MAb DB81 were sequenced. Due to its broad-spectrum anti-HIV-1 activity and lack of immunosuppressive effects, a humanized derivative of MAb DB81 could provide a useful complement to current preventive or therapeutic strategies against HIV-1.

  14. Murine concanavalin A-induced hepatitis is prevented by interleukin 12 (IL-12) antibody and exacerbated by exogenous IL-12 through an interferon-gamma-dependent mechanism

    DEFF Research Database (Denmark)

    Nicoletti, F; Di Marco, R; Zaccone, P

    2000-01-01

    Concanavalin A (ConA)-induced hepatitis is a cell-mediated immunoinflammatory condition similar to human autoimmune hepatitis. We investigated the role of interleukin 12 (IL-12) in hepatitis induced in NMRI and C57/BL6 mice by a single injection of ConA. Recombinant murine IL-12 administered 24...

  15. Radiolabeled antibody imaging

    International Nuclear Information System (INIS)

    Wahl, R.L.

    1987-01-01

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

  16. A systematic review and meta-analysis of cross-reactivity of antibodies induced by oil-in-water emulsion adjuvanted influenza H5N1 virus monovalent vaccines.

    Science.gov (United States)

    Chada, Kinnera E; Forshee, Richard; Golding, Hana; Anderson, Steven; Yang, Hong

    2017-05-31

    Cross-clade immunogenic stockpiled H5N1 vaccines may decrease the morbidity and transmission of infection during the initial phase of influenza pandemic. Meta-analysis of cross-reactive antibodies induced by oil-in-water emulsion adjuvanted (OWEA) influenza H5N1 virus monovalent vaccines with circulating heterologous H5N1 virus strains, isolated from human infections was performed. Literature search of MEDLINE, EMBASE, Web of Knowledge, The Cochrane Library, ClinicalTrials.gov, and International Standard Randomised Controlled Trial Number registry was conducted up through December 1, 2015. Methodologically qualified studies were included for (1) use of two doses of licensed OWEA (AS03 or MF59) egg-derived, inactivated influenza H5N1 virus monovalent vaccine, (2) participant age between 18 and 64years, and (3) evaluation of immunogenicity outcome for one or more subclade. Meta-analysis assessed the cross-reactivity of antibodies elicited by clade 1 adjuvanted vaccine strain against clade 2.1 virus strain (A/Vietnam/1194/2004 vs. A/Indonesia/05/2005); and separately against clade 2.2 virus strain (A/Vietnam/1194/2004 vs. A/turkey/Turkey/1/05); and clade 2.1 adjuvanted vaccine strain against clade 1 virus strain (A/Indonesia/05/2005 vs. A/Vietnam/1194/2004). Quantitative publication bias and influence analysis was conducted to evaluate potential impact of unpublished or new studies on the robustness of meta-analysis. Of 960 articles, 53 qualified for quality assessment and 15 studies met the inclusion criteria. All assessed clade pairs elicited cross-reactive antibodies (clade 1 against clade 2.1 and 2.2; clade 2.1 against clade 1, 2.2, and 2.3). Heterologous strains of same sub-clade are likely to elicit higher cross-reactive antibodies. OWEA influenza H5N1 virus monovalent vaccines exhibit broad cross-clade immunogenicity, a desired feature for vaccine stockpiling not yet demonstrated by unadjuvanted vaccines. In case of an impending H5N1 virus pandemic, stockpiled

  17. Assessment of the quality and quantity of naturally induced antibody responses to EBA175RIII-V in Ghanaian children living in two communities with varying malaria transmission patterns

    DEFF Research Database (Denmark)

    Abagna, Hamza B; Acquah, Festus K; Okonu, Ruth

    2018-01-01

    BACKGROUND: Recent global reports on malaria suggest significant decrease in disease severity and an increase in control interventions in many malaria endemic countries, including Ghana. However, a major driving force sustaining malaria transmission in recent times is the asymptomatic carriage...... of malaria parasites, which can enhance immune responses against parasite antigens. This study determined the prevalence and relative avidities of naturally induced antibodies to EBA175RIII-VLl in asymptomatic children living in two communities with varying malaria transmission patterns. METHODS: An asexual...... with perennial and seasonal malaria transmission, respectively. Venous blood samples were collected in July and October 2015 and again in January 2016. The multiplicity of infection and the genetic diversity of EBA175RIII circulating in both sites were also assessed using polymerase chain reaction. RESULTS...

  18. Relationship between natural and heme-mediated antibody polyreactivity

    Energy Technology Data Exchange (ETDEWEB)

    Hadzhieva, Maya; Vassilev, Tchavdar [Stephan Angelov Institute of Microbiology, Bulgarian Academy of Sciences, Sofia 1113 (Bulgaria); Bayry, Jagadeesh; Kaveri, Srinivas; Lacroix-Desmazes, Sébastien [Sorbonne Universités, UPMC Univ Paris 06, UMR-S 1138, Centre de Recherche des Cordeliers, F-75006 Paris (France); INSERM, UMR-S 1138, F-75006 Paris (France); Université Paris Descartes, Sorbonne Paris Cité, UMR-S 1138, F-75006 Paris (France); Dimitrov, Jordan D., E-mail: jordan.dimitrov@crc.jussieu.fr [Sorbonne Universités, UPMC Univ Paris 06, UMR-S 1138, Centre de Recherche des Cordeliers, F-75006 Paris (France); INSERM, UMR-S 1138, F-75006 Paris (France); Université Paris Descartes, Sorbonne Paris Cité, UMR-S 1138, F-75006 Paris (France)

    2016-03-25

    Polyreactive antibodies represent a considerable fraction of the immune repertoires. Some antibodies acquire polyreactivity post-translationally after interaction with various redox-active substances, including heme. Recently we have demonstrated that heme binding to a naturally polyreactive antibody (SPE7) results in a considerable broadening of the repertoire of recognized antigens. A question remains whether the presence of certain level of natural polyreactivity of antibodies is a prerequisite for heme-induced further extension of antigen binding potential. Here we used a second monoclonal antibody (Hg32) with unknown specificity and absence of intrinsic polyreactivity as a model to study the potential of heme to induce polyreactivity of antibodies. We demonstrated that exposure to heme greatly extends the antigen binding potential of Hg32, suggesting that the intrinsic binding promiscuity is not a prerequisite for the induction of polyreactivity by heme. In addition we compared the kinetics and thermodynamics of the interaction of heme-exposed antibodies with a panel of unrelated antigens. These analyses revealed that the two heme-sensitive antibodies adopt different mechanisms of binding to the same set of antigens. This study contributes to understanding the phenomenon of induced antibody polyreactivity. The data may also be of importance for understanding of physiological and pathological roles of polyreactive antibodies. - Highlights: • Exposure of certain monoclonal IgE antibodies to heme results in gain of antigen binding polyreactivity. • Natural polyreactivity of antibodies is dispensable for acquisition of polyreactivity through interaction with heme. • Heme-induced monoclonal IgE antibodies differ in their thermodynamic mechanisms of antigen recognition.

  19. An adjuvanted, tetravalent dengue virus purified inactivated vaccine candidate induces long-lasting and protective antibody responses against dengue challenge in rhesus macaques.

    Science.gov (United States)

    Fernandez, Stefan; Thomas, Stephen J; De La Barrera, Rafael; Im-Erbsin, Rawiwan; Jarman, Richard G; Baras, Benoît; Toussaint, Jean-François; Mossman, Sally; Innis, Bruce L; Schmidt, Alexander; Malice, Marie-Pierre; Festraets, Pascale; Warter, Lucile; Putnak, J Robert; Eckels, Kenneth H

    2015-04-01

    The immunogenicity and protective efficacy of a candidate tetravalent dengue virus purified inactivated vaccine (TDENV PIV) formulated with alum or an Adjuvant System (AS01, AS03 tested at three different dose levels, or AS04) was evaluated in a 0, 1-month vaccination schedule in rhesus macaques. One month after dose 2, all adjuvanted formulations elicited robust and persisting neutralizing antibody titers against all four dengue virus serotypes. Most of the formulations tested prevented viremia after challenge, with the dengue serotype 1 and 2 virus strains administered at 40 and 32 weeks post-dose 2, respectively. This study shows that inactivated dengue vaccines, when formulated with alum or an Adjuvant System, are candidates for further development. © The American Society of Tropical Medicine and Hygiene.

  20. Pan-HER - an antibody mixture targeting EGFR, HER2, and HER3 abrogates preformed and ligand-induced EGFR homo- and heterodimers

    DEFF Research Database (Denmark)

    Ellebaek, Sofie; Pedersen, Susanne Brix; Grandal, Michael

    2016-01-01

    The human epidermal growth factor receptor (HER)-family is involved in development of many epithelial cancers. Therefore, HER-family members constitute important targets for anti-cancer therapeutics such as monoclonal antibodies (mAbs). A limitation to the success of single HER-targeting m...... with Pan-HER were investigated by in situ proximity ligation assay and co-immunoprecipitation, demonstrating that Pan-HER and the EGFR-targeting mAb mixture efficiently down-regulate basal EGFR homo- and heterodimerization in two tested cell lines, whereas single mAbs had limited effects. Pan...... development of Pan-HER in resistant settings. This article is protected by copyright. All rights reserved....

  1. Anti-alpha4beta1 integrin antibody induces receptor internalization and does not impair the function of circulating neutrophilic leukocytes.

    Science.gov (United States)

    Fleming, Jennifer C; Bao, Feng; Cepinskas, Gediminas; Weaver, Lynne C

    2010-08-01

    A compelling strategy for treatment of spinal cord injury is the blockade of integrin-mediated leukocyte extravasation using a monoclonal antibody (mAb) against the alpha4 subunit of the alpha4beta1-integrin. However, little is known with respect to neutrophil function following anti-alpha4 mAb treatment. This study assessed the effects of anti-alpha4 mAb binding on neutrophil activation [reactive oxygen species (ROS) production], function (phagocytic activity) and anti-alpha4-mAb/alpha4beta1-integrin-complex internalization. Resting, primed or stimulated rat neutrophils were incubated ex vivo with anti-alpha4 mAb or isotype-control antibody. ROS production, phagocytic activity, and anti-alpha4-mAb/alpha4beta1-integrin-complex internalization were determined by flow cytometry using dihydrorhodamine (DHR1,2,3), fluorescent microspheres, and indirect immunolabeling, respectively. Brief (0.5 h) incubation of resting, primed or activated neutrophils with anti-alpha4 mAb had no effect on ROS production and did not change neutrophil phagocytic activity. However, prolonged incubation (2 h), assessed only in resting neutrophils, increased ROS production. The anti-alpha4-mAb/alpha4beta1-integrin-complex was internalized after 1 h of anti-alpha4 mAb treatment and remained internalized up to 6 h. Neutrophil ROS production and phagocytic function remain unaltered after brief anti-alpha4 mAb exposure, demonstrating that use of this mAb as a treatment should not adversely affect important beneficial roles of these cells.

  2. Biocompatible chitosan nanoparticles as an efficient delivery vehicle for Mycobacterium tuberculosis lipids to induce potent cytokines and antibody response through activation of γδ T cells in mice

    Science.gov (United States)

    Das, Ishani; Padhi, Avinash; Mukherjee, Sitabja; Dash, Debi P.; Kar, Santosh; Sonawane, Avinash

    2017-04-01

    The activation of cell-mediated and humoral immune responses to Mycobacterium tuberculosis (Mtb) is critical for protection against the pathogen and nanoparticle-mediated delivery of antigens is a more potent way to induce different immune responses. Herein, we show that mice immunized with Mtb lipid-bound chitosan nanoparticles (NPs) induce secretion of prominent type-1 T-helper (Th-1) and type-2 T-helper (Th-2) cytokines in lymph node and spleen cells, and also induces significantly higher levels of IgG, IgG1, IgG2 and IgM in comparison to control mice. Furthermore, significantly enhanced γδ-T-cell activation was observed in lymph node cells isolated from mice immunized with Mtb lipid-coated chitosan NPs as compared to mice immunized with chitosan NPs alone or Mtb lipid liposomes. In comparison to CD8+ cells, significantly higher numbers of CD4+ cells were present in both the lymph node and spleen cells isolated from mice immunized with Mtb lipid-coated chitosan NPs. In conclusion, this study represents a promising new strategy for the efficient delivery of Mtb lipids using chitosan NPs to trigger an enhanced cell-mediated and antibody response against Mtb lipids.

  3. MF59- and Al(OH)3-Adjuvanted Staphylococcus aureus (4C-Staph) Vaccines Induce Sustained Protective Humoral and Cellular Immune Responses, with a Critical Role for Effector CD4 T Cells at Low Antibody Titers

    Science.gov (United States)

    Monaci, Elisabetta; Mancini, Francesca; Lofano, Giuseppe; Bacconi, Marta; Tavarini, Simona; Sammicheli, Chiara; Arcidiacono, Letizia; Giraldi, Monica; Galletti, Bruno; Rossi Paccani, Silvia; Torre, Antonina; Fontana, Maria Rita; Grandi, Guido; de Gregorio, Ennio; Bensi, Giuliano; Chiarot, Emiliano; Nuti, Sandra; Bagnoli, Fabio; Soldaini, Elisabetta; Bertholet, Sylvie

    2015-01-01

    Staphylococcus aureus (S. aureus) is an important opportunistic pathogen that may cause invasive life-threatening infections, like sepsis and pneumonia. Due to the increasing antibiotic resistance, the development of an effective vaccine against S. aureus is needed. Although a correlate of protection against staphylococcal diseases is not yet established, several findings suggest that both antibodies and CD4 T cells might contribute to optimal immunity. In this study, we show that adjuvanting a multivalent vaccine (4C-Staph) with MF59, an oil-in-water emulsion licensed in human vaccines, further potentiated antigen-specific IgG titers and CD4 T-cell responses compared to alum and conferred protection in the peritonitis model of S. aureus infection. Moreover, we showed that MF59- and alum-adjuvanted 4C-Staph vaccines induced persistent antigen-specific humoral and T-cell responses, and protected mice from infection up to 4 months after immunization. Furthermore, 4C-Staph formulated with MF59 was used to investigate which immune compartment is involved in vaccine-induced protection. Using CD4 T cell-depleted mice or B cell-deficient mice, we demonstrated that both T and B-cell responses contributed to 4C-Staph vaccine-mediated protective immunity. However, the role of CD4 T cells seemed more evident in the presence of low-antibody responses. This study provides preclinical data further supporting the use of the adjuvanted 4C-Staph vaccines against S. aureus diseases, and provides critical insights on the correlates of protective immunity necessary to combat this pathogen. PMID:26441955

  4. A replicating modified vaccinia tiantan strain expressing an avian-derived influenza H5N1 hemagglutinin induce broadly neutralizing antibodies and cross-clade protective immunity in mice.

    Directory of Open Access Journals (Sweden)

    Haixia Xiao

    Full Text Available To combat the possibility of a zoonotic H5N1 pandemic in a timely fashion, it is necessary to develop a vaccine that would confer protection against homologous and heterologous human H5N1 influenza viruses. Using a replicating modified vaccinia virus Tian Tan strain (MVTT as a vaccine vector, we constructed MVTTHA-QH and MVTTHA-AH, which expresses the H5 gene of a goose-derived Qinghai strain A/Bar-headed Goose/Qinghai/1/2005 or human-derived Anhui Strain A/Anhui/1/2005. The immunogenicity profiles of both vaccine candidates were evaluated. Vaccination with MVTTHA-QH induced a significant level of neutralizing antibodies (Nabs against a homologous strain and a wide range of H5N1 pseudoviruses (clades 1, 2.1, 2.2, 2.3.2, and 2.3.4. Neutralization tests (NT and Haemagglutination inhibition (HI antibodies inhibit the live autologous virus as well as a homologous A/Xingjiang/1/2006 and a heterologous A/Vietnam/1194/2004, representing two human isolates from clade 2.2 and clade 1, respectively. Importantly, mice vaccinated with intranasal MVTTHA-QH were completely protected from challenge with lethal dosages of A/Bar-headed Goose/Qinghai/1/2005 and the A/Viet Nam/1194/2004, respectively, but not control mice that received a mock MVTTS vaccine. However, MVTTHA-AH induced much lower levels of NT against its autologous strain. Our results suggest that it is feasible to use the H5 gene from A/Bar-headed Goose/Qinghai/1/2005 to construct an effective vaccine, when using MVTT as a vector, to prevent infections against homologous and genetically divergent human H5N1 influenza viruses.

  5. MF59- and Al(OH3-adjuvanted Staphylococcus aureus (4C-Staph vaccines induce sustained protective humoral and cellular immune responses, with a critical role for effector CD4 T cells at low antibody titers.

    Directory of Open Access Journals (Sweden)

    Elisabetta eMonaci

    2015-09-01

    Full Text Available Staphylococcus aureus (S. aureus is an important opportunistic pathogen that may cause invasive life-threatening infections like sepsis and pneumonia. Due to increasing antibiotic-resistance, the development of an effective vaccine against S. aureus is needed. Although a correlate of protection against staphylococcal diseases is not yet established, several findings suggest that both antibodies and CD4 T cells might contribute to optimal immunity. In this study, we show that adjuvanting a multivalent vaccine (4C-Staph with MF59, an oil-in-water emulsion licensed in human vaccines, further potentiated antigen-specific IgG titers and CD4 T cell responses compared to alum and conferred protection in the peritonitis model of S. aureus infection. Moreover, we showed that MF59- and alum-adjuvanted 4C-Staph vaccines induced persistent antigen-specific humoral and T cell responses, and protected mice from infection up to 4 months after immunization. Furthermore, 4C-Staph formulated with MF59 was used to investigate which immune compartment is involved in vaccine-induced protection. Using CD4 T cell-depleted mice or B cell deficient mice, we demonstrated that both T and B cell responses contributed to 4C-Staph vaccine-mediated protective immunity. However, the role of CD4 T cells seemed more evident in the presence of low antibody responses. This study provides preclinical data further supporting the use of the adjuvanted 4C-Staph vaccines against S. aureus diseases, and provides critical insights on the correlates of protective immunity necessary to combat this pathogen.

  6. Vascular localization of heparan sulfate proteoglycans in retinas of patients with diabetes mellitus and in VEGF-induced retinopathy using domain-specific antibodies

    NARCIS (Netherlands)

    Witmer, A. N.; van den Born, J.; Vrensen, G. F.; Schlingemann, R. O.

    2001-01-01

    PURPOSE: The Steno hypothesis (Deckert et al. ) states that in diabetes mellitus (DM), changes in vascular heparan sulfate proteoglycan (HSPG) expression are involved in systemic endothelial dysfunction and increased capillary permeability. In diabetes-induced glomerular capillary leakage, loss of

  7. 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