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Sample records for acidic protein antibodies

  1. Profiling protein thiol oxidation in tumor cells using sulfenic acid-specific antibodies.

    Science.gov (United States)

    Seo, Young Ho; Carroll, Kate S

    2009-09-22

    Hydrogen peroxide (H2O2) functions as a second messenger that can activate cell proliferation through chemoselective oxidation of cysteine residues in signaling proteins. The connection between H2O2 signaling, thiol oxidation, and activation of growth pathways has emerged as fertile ground for the development of strategies for cancer treatment. Central to achieving this goal is the development of tools and assays that facilitate characterization of the molecular events associated with tumorigenesis and evaluation of patient response to therapy. Here we report on the development of an immunochemical method for detecting sulfenic acid, the initial oxidation product that results when a thiolate reacts with H2O2. For this approach, the sulfenic acid is derivatized with a chemical tag to generate a unique epitope for recognition. The elicited antibody is exquisitely specific, context-independent, and capable of visualizing sulfenic acid formation in cells. Applying this approach to several systems, including cancer cell lines, shows it can be used to monitor differences in thiol redox status and reveals a diverse pattern of sulfenic acid modifications across different subtypes of breast tumors. These studies demonstrate a general strategy for producing antibodies against a specific oxidation state of cysteine and show the utility of these reagents for profiling thiol oxidation associated with pathological conditions such as breast cancer.

  2. 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 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.

  3. Change of glutamic acid decarboxylase antibody and protein tyrosine phosphatase antibody in Chinese patients with acute-onset type 1 diabetes mellitus

    Institute of Scientific and Technical Information of China (English)

    CHAO Chen; HUANG Gan; LI Xia; YANG Lin; LIN Jian; JIN Ping; LUO Shuo-ming

    2013-01-01

    Background Glutamic acid decarboxylase antibody (GADA) and protein tyrosine phosphatase antibody (IA-2A) are two major autoantibodies,which exert important roles in the process of type 1 diabetes mellitus (T1D).Our study aimed to investigate the changes in positivity and titers of GADA and IA-2A during the course of Chinese acute-onset T1D patients and their relationships with clinical features.Methods Two hundreds and forty-seven Chinese newly diagnosed acute-onset T1D patients were consecutively recruited.GADA and IA-2A were detected at the time of diagnosis,one year later,3-5 years later after diagnosis during the follow-up; all the clinical data were recorded and analyzed as well.Results During the course of acute-onset T1D,the majority of patients remained stable for GADA or IA-2A,however,a few patients changed from positivity to negativity and fewer patients converted from negativity to positivity.The prevalence of GADA was 56.3% at diagnosis,decreasing to 50.5% one year later,and 43.3% 3-5 years later while the corresponding prevalence of IA-2A were 32.8%,31.0% and 23.3%,respectively.The median GADA titers were 0.0825 at diagnosis,declining to 0.0585 one year later and 0.0383 3-5 years later (P <0.001),while the corresponding median titers were 0.0016,0.0010,0.0014 for IA-2A,respectively.Fasting C-peptide (FCP) and postprandial C-peptide 2 hours (PCP2h)levels of GADA or IA-2A negativity persistence patients were higher than those of positivity persistence and negativity conversion patients (P <0.05) which indicated GADA or IA-2A negativity persistence T1D patients had a less loss of β cell function.Conclusion Our data suggest that repeated detection of GADA and IA-2A are necessary for differential diagnosis of autoimmune diabetes and the indirect prediction of the β cell function in Chinese patients.

  4. Profiling protein thiol oxidation in tumor cells using sulfenic acid-specific antibodies

    OpenAIRE

    Seo, Young Ho; Carroll, Kate S.

    2009-01-01

    Hydrogen peroxide (H2O2) functions as a second messenger that can activate cell proliferation through chemoselective oxidation of cysteine residues in signaling proteins. The connection between H2O2 signaling, thiol oxidation, and activation of growth pathways has emerged as fertile ground for the development of strategies for cancer treatment. Central to achieving this goal is the development of tools and assays that facilitate characterization of the molecular events associated with tumorig...

  5. 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.

  6. A novel approach for measuring sphingosine-1-phosphate and lysophosphatidic acid binding to carrier proteins using monoclonal antibodies and the Kinetic Exclusion Assay.

    Science.gov (United States)

    Fleming, Jonathan K; Glass, Thomas R; Lackie, Steve J; Wojciak, Jonathan M

    2016-09-01

    Sphingosine-1-phosphate (S1P) and lysophosphatidic acid (LPA) are bioactive signaling lysophospholipids that activate specific G protein-coupled receptors on the cell surface triggering numerous biological events. In circulation, S1P and LPA associate with specific carrier proteins or chaperones; serum albumin binds both S1P and LPA while HDL shuttles S1P via interactions with apoM. We used a series of kinetic exclusion assays in which monoclonal anti-S1P and anti-LPA antibodies competed with carrier protein for the lysophospholipid to measure the equilibrium dissociation constants (Kd) for these carrier proteins binding S1P and the major LPA species. Fatty acid-free (FAF)-BSA binds these lysophospholipids with the following Kd values: LPA(16:0), 68 nM; LPA(18:1), 130 nM; LPA(18:2), 350 nM; LPA(20:4), 2.2 μM; and S1P, 41 μM. FAF human serum albumin binds each lysophospholipid with comparable affinities. By measuring the apoM concentration and expanding the model to include endogenous ligand, we were able to resolve the Kd values for S1P binding apoM in the context of human HDL and LDL particles (21 nM and 2.4 nM, respectively). The novel competitive assay and analysis described herein enables measurement of Kd values of completely unmodified lysophospholipids binding unmodified carrier proteins in solution, and thus provide insights into S1P and LPA storage in the circulation system and may be useful in understanding chaperone-dependent receptor activation and signaling. PMID:27444045

  7. Phospho-Specific Antibody Probes of Intermediate Filament Proteins.

    Science.gov (United States)

    Goto, Hidemasa; Tanaka, Hiroki; Kasahara, Kousuke; Inagaki, Masaki

    2016-01-01

    Intermediate filaments (IFs) form one of the major cytoskeletal systems in the cytoplasm or beneath the nuclear membrane. Accumulating data have suggested that IF protein phosphorylation dramatically changes IF structure/dynamics in cells. For the production of an antibody recognizing site-specific protein phosphorylation (a site- and phosphorylation state-specific antibody), we first employed a strategy to immunize animals with an in vitro-phosphorylated polypeptide or a phosphopeptide (corresponding to a phosphorylated residue and its surrounding sequence of amino acids), instead of a phosphorylated protein. Our established methodology not only improves the chance of obtaining a phospho-specific antibody but also has the advantage that one can predesign a targeted phosphorylation site. It is now applied to the production of an antibody recognizing other types of site-specific posttranslational modification, such as acetylation or methylation. The use of such an antibody in immunocytochemistry enables us to analyze spatiotemporal distribution of site-specific IF protein phosphorylation. The antibody is of great use to identify a protein kinase responsible for in vivo IF protein phosphorylation and to monitor intracellular kinase activities through IF protein phosphorylation. Here, we present an overview of our methodology and describe stepwise approaches for the antibody characterization. We also provide some examples of analyses for IF protein phosphorylation involved in mitosis and signal transduction.

  8. Functional characterization of antibodies against Neisseria gonorrhoeae opacity protein loops.

    Directory of Open Access Journals (Sweden)

    Jessica G Cole

    Full Text Available BACKGROUND: The development of a gonorrhea vaccine is challenged by the lack of correlates of protection. The antigenically variable neisserial opacity (Opa proteins are expressed during infection and have a semivariable (SV and highly conserved (4L loop that could be targeted in a vaccine. Here we compared antibodies to linear (Ab(linear and cyclic (Ab(cyclic peptides that correspond to the SV and 4L loops and selected hypervariable (HV(2 loops for surface-binding and protective activity in vitro and in vivo. METHODS/FINDINGS: Ab(SV cyclic bound a greater number of different Opa variants than Ab(SV linear, including variants that differed by seven amino acids. Antibodies to the 4L peptide did not bind Opa-expressing bacteria. Ab(SV (cyclic and Ab(HV2 (cyclic, but not Ab(SV (linear or Ab(HV2 linear agglutinated homologous Opa variants, and Ab(HV2BD (cyclic but not Ab(HV2BD (linear blocked the association of OpaB variants with human endocervical cells. Only Ab(HV2BD (linear were bactericidal against the serum resistant parent strain. Consistent with host restrictions in the complement cascade, the bactericidal activity of Ab(HV2BD (linear was increased 8-fold when rabbit complement was used. None of the antibodies was protective when administered vaginally to mice. Antibody duration in the vagina was short-lived, however, with <50% of the antibodies recovered 3 hrs post-administration. CONCLUSIONS: We conclude that an SV loop-specific cyclic peptide can be used to induce antibodies that recognize a broad spectrum of antigenically distinct Opa variants and have agglutination abilities. HV(2 loop-specific cyclic peptides elicited antibodies with agglutination and adherence blocking abilities. The use of human complement when testing the bactericidal activity of vaccine-induced antibodies against serum resistant gonococci is also important.

  9. Cerebellar Ataxia and Glutamic Acid Decarboxylase Antibodies

    Science.gov (United States)

    Ariño, Helena; Gresa-Arribas, Nuria; Blanco, Yolanda; Martínez-Hernández, Eugenia; Sabater, Lidia; Petit-Pedrol, Mar; Rouco, Idoia; Bataller, Luis; Dalmau, Josep O.; Saiz, Albert; Graus, Francesc

    2016-01-01

    IMPORTANCE Current clinical and immunologic knowledge on cerebellar ataxia (CA) with glutamic acid decarboxylase 65 antibodies (GAD65-Abs) is based on case reports and small series with short-term follow-up data. OBJECTIVE To report the symptoms, additional antibodies, prognostic factors, and long-term outcomes in a cohort of patients with CA and GAD65-Abs. DESIGN, SETTING, AND PARTICIPANTS Retrospective cohort study and laboratory investigations at a center for autoimmune neurologic disorders among 34 patients with CA and GAD65-Abs, including 25 with long-term follow-up data (median, 5.4 years; interquartile range, 3.1-10.3 years). MAIN OUTCOMES AND MEASURES Analysis of clinicoimmunologic features and predictors of response to immunotherapy. Immunochemistry on rat brain, cultured neurons, and human embryonic kidney cells expressing GAD65, GAD67, α1-subunit of the glycine receptor, and a repertoire of known cell surface autoantigens were used to identify additional antibodies. Twenty-eight patients with stiff person syndrome and GAD65-Abs served as controls. RESULTS The median age of patients was 58 years (range, 33-80 years); 28 of 34 patients (82%) were women. Nine patients (26%) reported episodes of brainstem and cerebellar dysfunction or persistent vertigo several months before developing CA. The clinical presentation was subacute during a period of weeks in 13 patients (38%). Nine patients (26%) had coexisting stiff person syndrome symptoms. Systemic organ-specific autoimmunities (type 1 diabetes mellitus and others) were present in 29 patients (85%). Twenty of 25 patients with long-term follow-up data received immunotherapy (intravenous immunoglobulin in 10 and corticosteroids and intravenous immunoglobulin or other immunosuppressors in 10), and 7 of them (35%) improved. Predictors of clinical response included subacute onset of CA (odds ratio [OR], 0.50; 95% CI, 0.25-0.99; P = .047) and prompt immunotherapy (OR, 0.98; 95% CI, 0.96-0.99; P = .01). Similar

  10. The production of antibody fragments and antibody fusion proteins by yeasts and filamentous fungi

    NARCIS (Netherlands)

    Joosten, V.; Lokman, C.; Hondel, C.A.M.J.J. van den; Punt, P.J.

    2003-01-01

    In this review we will focus on the current status and views concerning the production of antibody fragments and antibody fusion proteins by yeasts and filamentous fungi. We will focus on single-chain antibody fragment production (scFv and VHH) by these lower eukaryotes and the possible applications

  11. Capture ELISA for IgM antibodies against Plasmodium falciparum glutamate rich protein

    DEFF Research Database (Denmark)

    Dziegiel, Morten Hanefeld; Borre, M B; Petersen, E;

    1992-01-01

    This report describes a novel mu chain capture ELISA for the detection of IgM antibodies against a Plasmodium falciparum antigen. A fragment of the 220 kDa P. falciparum glutamate rich protein containing amino acid residues 489-1271 was expressed in E. coli as a recombinant chimeric beta-galactos......This report describes a novel mu chain capture ELISA for the detection of IgM antibodies against a Plasmodium falciparum antigen. A fragment of the 220 kDa P. falciparum glutamate rich protein containing amino acid residues 489-1271 was expressed in E. coli as a recombinant chimeric beta...

  12. Monoclonal antibodies against plant proteins recognise animal intermediate filaments.

    Science.gov (United States)

    Parke, J M; Miller, C C; Cowell, I; Dodson, A; Dowding, A; Downes, M; Duckett, J G; Anderton, B J

    1987-01-01

    Four monoclonal antibodies were raised against polypeptides present in a high-salt detergent-insoluble fraction from cells of Chlamydomonas reinhardtii. Indirect immunofluorescence microscopy of fibroblasts and epithelial cells grown in culture using these plant antibodies revealed staining arrays identical to those obtained with well characterised antibodies to animal intermediate filaments. Immunofluorescence microscopy of Chlamydomonas with these monoclonal antibodies and a monoclonal antibody that recognises all animal intermediate filaments (anti-IFA) gave a diffuse, patchy cytoplasmic staining pattern. Both the plant antibodies and anti-IFA stained interphase onion root tip cells in a diffuse perinuclear pattern. In metaphase through to telophase, the labelling patterns colocalised with those of microtubules. Labelling of the phragmoplast was also detected but not staining of the preprophase band. On Western blots of various animal cell lines and tissues, all the antibodies labelled known intermediate filament proteins. On Western blots of whole Chlamydomonas proteins, all the antibodies labelled a broad band in the 57,000 Mr range, and three antibodies labelled bands around 66,000 and 140,000 Mr but with variable intensities. On Western blots of whole onion root tip proteins, all the antibodies labelled 50,000 Mr (two to three bands) polypeptides and a diffuse band around 60,000 Mr and three of the antibodies also labelled several polypeptides in the 90,000-200,000 Mr range. The consistent labelling of these different bands by several different monoclonal antibodies recognising animal intermediate filaments makes these polypeptides putative plant intermediate filament proteins. PMID:2446785

  13. Automatic Identification of Antibodies in the Protein Data Bank

    Institute of Scientific and Technical Information of China (English)

    LI Xun; WANG Renxiao

    2009-01-01

    An automatic method has been developed for identifying antibody entries in the protein data bank (PDB). Our method, called KIAb (Keyword-based Identification of Antibodies), parses PDB-format files to search for particular keywords relevant to antibodies, and makes judgment accordingly. Our method identified 780 entries as antibodies on the entire PDB. Among them, 767 entries were confirmed by manual inspection, indicating a high success rate of 98.3%. Our method recovered basically all of the entries compiled in the Summary of Antibody Crystal Structures (SACS) database. It also identified a number of entries missed by SACS. Our method thus provides a more com-plete mining of antibody entries in PDB with a very low false positive rate.

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

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    Michał Śmiga

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

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

    Science.gov (United States)

    Śmiga, Michał; Bielecki, Marcin; Olczak, Mariusz; Smalley, John W; Olczak, Teresa

    2015-01-01

    Given the emerging evidence of an association between periodontal infections and systemic conditions, the search for specific methods to detect the presence of P. gingivalis, a principal etiologic agent in chronic periodontitis, is of high importance. The aim of this study was to characterize antibodies raised against purified P. gingivalis HmuY protein and selected epitopes of the HmuY molecule. Since other periodontopathogens produce homologs of HmuY, we also aimed to characterize responses of antibodies raised against the HmuY protein or its epitopes to the closest homologous proteins from Prevotella intermedia and Tannerella forsythia. Rabbits were immunized with purified HmuY protein or three synthetic, KLH-conjugated peptides, derived from the P. gingivalis HmuY protein. The reactivity of anti-HmuY antibodies with purified proteins or bacteria was determined using Western blotting and ELISA assay. First, we found homologs of P. gingivalis HmuY in P. intermedia (PinO and PinA proteins) and T. forsythia (Tfo protein) and identified corrected nucleotide and amino acid sequences of Tfo. All proteins were overexpressed in E. coli and purified using ion-exchange chromatography, hydrophobic chromatography and gel filtration. We demonstrated that antibodies raised against P. gingivalis HmuY are highly specific to purified HmuY protein and HmuY attached to P. gingivalis cells. No reactivity between P. intermedia and T. forsythia or between purified HmuY homologs from these bacteria and anti-HmuY antibodies was detected. The results obtained in this study demonstrate that P. gingivalis HmuY protein may serve as an antigen for specific determination of serum antibodies raised against this bacterium. PMID:25658942

  16. Human Dengue Antibodies against Structural and Nonstructural Proteins

    OpenAIRE

    Valdés, Katia; Alvarez, Mayling; Pupo, Maritza; Vázquez, Susana; Rodríguez, Rayner; Guzmán, María G.

    2000-01-01

    Antibodies against dengue virus type 2 and 4 proteins in acute-phase sera of 10 primary and 10 secondary dengue fever and dengue hemorrhagic fever patients were studied by Western blotting. In the first group the immune response was barely detectable, while in the second group more proteins were detected, with a very strong reaction. Anti-NS1 and -NS3 antibodies were detected mainly in secondary cases. Anti-E, -NS3, and -NS5 antibodies were detected in a high number of cases. The possibility ...

  17. Antibody-based protein detection using piezoresistive cantilever arrays

    Science.gov (United States)

    Dauksaite, Vita; Lorentzen, Martin; Besenbacher, Flemming; Kjems, Jørgen

    2007-03-01

    A piezoresistive cantilever array platform with electrical read-out was applied for protein detection using GST (glutathione-S-transferase) and GST antibodies as a model system. Sensing was performed in the static deflection mode under constant flow conditions. The GST antibodies were directly immobilized on the cantilever gold surface by means of free thiol groups. The setup allowed simultaneous deflection measurements with sensor and control-antibody-immobilized reference cantilevers and enabled detection of 1 ng µl-1 (40 nM) of GST protein, which is similar to the sensitivity reported for cantilever sensors using an optical read-out system.

  18. Protein X of Streptococcus agalactiae induces opsonic antibodies in cows.

    OpenAIRE

    Rainard, P; Lautrou, Y; Sarradin, P.; Poutrel, B

    1991-01-01

    Protein X of Streptococcus agalactiae is a surface protein frequently associated with strains isolated from cases of mastitis of dairy cows. By immunizing cows with purified protein X, we obtained an antibody response which was restricted to X-bearing strains of S. agalactiae in a whole-cell enzyme-linked immunosorbent assay. This response resulted in an increase in the opsonic activity of serum for strains bearing protein X, as assessed through the augmentation of the chemiluminescence respo...

  19. Limited cross-reactivity of mouse monoclonal antibodies against Dengue virus capsid protein among four serotypes

    Directory of Open Access Journals (Sweden)

    Noda M

    2012-11-01

    Full Text Available Megumi Noda,1 Promsin Masrinoul,1 Chaweewan Punkum,1 Chonlatip Pipattanaboon,2,3 Pongrama Ramasoota,2,4 Chayanee Setthapramote,2,3 Tadahiro Sasaki,6 Mikiko Sasayama,1 Akifumi Yamashita,1,5 Takeshi Kurosu,6 Kazuyoshi Ikuta,6 Tamaki Okabayashi11Mahidol-Osaka Center for Infectious Diseases, 2Center of Excellence for Antibody Research, 3Department of Microbiology and Immunology, 4Department of Social and Environmental Medicine, Faculty of Tropical Medicine, Mahidol University, Ratchathewi, Bangkok, Thailand; 5Graduate School of Life Science, Tohoku University, Sendai, Miyagi, 6Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, JapanBackground: Dengue illness is one of the important mosquito-borne viral diseases in tropical and subtropical regions. Four serotypes of dengue virus (DENV-1, DENV-2, DENV-3, and DENV-4 are classified in the Flavivirus genus of the family Flaviviridae. We prepared monoclonal antibodies against DENV capsid protein from mice immunized with DENV-2 and determined the cross-reactivity with each serotype of DENV and Japanese encephalitis virus.Methods and results: To clarify the relationship between the cross-reactivity of monoclonal antibodies and the diversity of these viruses, we examined the situations of flaviviruses by analyses of phylogenetic trees. Among a total of 60 prepared monoclonal antibodies specific for DENV, five monoclonal antibodies stained the nuclei of infected cells and were found to be specific to the capsid protein. Three were specific to DENV-2, while the other two were cross-reactive with DENV-2 and DENV-4. No monoclonal antibodies were cross-reactive with all four serotypes. Phylogenetic analysis of DENV amino acid sequences of the capsid protein revealed that DENV-2 and DENV-4 were clustered in the same branch, while DENV-1 and DENV-3 were clustered in the other branch. However, these classifications of the capsid protein were different from those of the

  20. Antigenic specificity of serum antibodies in mice fed soy protein

    DEFF Research Database (Denmark)

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

    2003-01-01

    Background: Soybean protein is used in a number of food products but unfortunately is also a common cause of food allergy. Upon ingestion of soy protein, healthy mice like other animals and humans generate a soy-specific antibody response in the absence of signs of illness. Not much is known about...

  1. Preparation of monoclonal antibodies against radiation-induced protein

    International Nuclear Information System (INIS)

    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)

  2. Antibodies to a recombinant glutamate-rich Plasmodium falciparum protein

    DEFF Research Database (Denmark)

    Hogh, B; Petersen, E; Dziegiel, M;

    1992-01-01

    A Plasmodium falciparum antigen gene coding for a 220-kD glutamate-rich protein (GLURP) has been cloned, and the 783 C-terminal amino acids of this protein (GLURP489-1271) have been expressed as a beta-galactosidase fusion protein in Escherichia coli. The encoded 783 amino acid residues contain two...

  3. The Protein-Protein Interface Evolution Acts in a Similar Way to Antibody Affinity Maturation*

    OpenAIRE

    Li, Bohua; Zhao, Lei; Wang, Chong; Guo, Huaizu; Wu, Lan; Zhang, Xunming; Qian, Weizhu; Wang, Hao; Guo, Yajun

    2009-01-01

    Understanding the evolutionary mechanism that acts at the interfaces of protein-protein complexes is a fundamental issue with high interest for delineating the macromolecular complexes and networks responsible for regulation and complexity in biological systems. To investigate whether the evolution of protein-protein interface acts in a similar way as antibody affinity maturation, we incorporated evolutionary information derived from antibody affinity maturation with common simulation techniq...

  4. Anti-glutamic acid decarboxylase antibody positive neurological syndromes.

    Science.gov (United States)

    Tohid, Hassaan

    2016-07-01

    A rare kind of antibody, known as anti-glutamic acid decarboxylase (GAD) autoantibody, is found in some patients. The antibody works against the GAD enzyme, which is essential in the formation of gamma aminobutyric acid (GABA), an inhibitory neurotransmitter found in the brain. Patients found with this antibody present with motor and cognitive problems due to low levels or lack of GABA, because in the absence or low levels of GABA patients exhibit motor and cognitive symptoms. The anti-GAD antibody is found in some neurological syndromes, including stiff-person syndrome, paraneoplastic stiff-person syndrome, Miller Fisher syndrome (MFS), limbic encephalopathy, cerebellar ataxia, eye movement disorders, and epilepsy. Previously, excluding MFS, these conditions were calledhyperexcitability disorders. However, collectively, these syndromes should be known as "anti-GAD positive neurological syndromes." An important limitation of this study is that the literature is lacking on the subject, and why patients with the above mentioned neurological problems present with different symptoms has not been studied in detail. Therefore, it is recommended that more research is conducted on this subject to obtain a better and deeper understanding of these anti-GAD antibody induced neurological syndromes. PMID:27356651

  5. Preparation and characterization of polyclonal antibodies against ARL-1 protein

    Institute of Scientific and Technical Information of China (English)

    Jun-Fei Jin; Liu-Di Yuan; Li Liu; Zhu-Jiang Zhao; Wei Xie

    2003-01-01

    AIM: To prepare and characterize polyclonal antibodies against aldose reductase-like (ARL-1) protein.METHODS: ARL-L gene was inserted into the E.coli expression vector pGEX-4T-1(His)6C and vector pQE-30. Recombinant ARL1 proteins named ARL-(His)6 and ARL-GST were expressed.They were purified by affinity chromatography. Sera from domestic rabbits immunized with ARL-(His)6 were purified by CNBr-activated sepharose 4B coupled ARL-GST. Polyclonal antibodies were detected by Western blotting.RESULTS: Recombinant proteins of ARL-(His)6 with molecular weight of 35.7 KD and ARL-GST with molecular weight of 60.8 KD were highly expressed. The expression levels of ARL-GST and ARL-(His)6 were 15.1% and 27.7 %among total bacteria proteins, respectively. They were soluble, predominantly in supernatant. After purification by non-denatured way, SDS-PAGE showed one band. In the course of polyclonal antibodies purification, only one elution peak could be seen. Western blotting showed positive signals in the two purified proteins and the bacteria transformed with pGEX-4T-1(His)6 C-ARL and pQE-30-ARL individually.CONCLUSION: Polyclonal antibodies are purified and highly specific against ARL-1 protein. ARL-GST and ARL-(His)6 are highly expressed and purified.

  6. Generation and Identification of Monoclonal Antibody Against Porcine Adipocyte Plasma Membrane Proteins

    Institute of Scientific and Technical Information of China (English)

    CAO Jin-ling; CHEN Jian-jie; WANG Zhi-rui; WANG Jun-dong

    2007-01-01

    Production of monoclonal antibody against porcine adipocyte plasma membrane proteins to explore a new way of controlling body fat deposition and improving carcass quality is discussed in this article. Membrane proteins of pig adipocyte plasma membrane proteins were extracted with the help of sucrose density gradient centrifugation, and two kinds of proteins were obtained. The monoclonal antibody (designated 3B2 and 3F3) of IgGl and IgG2b subclass against adipocyte membrane proteins were produced by immunization, with adipocyte membrane proteins as an antigen, and its titer was 1:105 detected by enzyme-linked immunoadsorbent assay (ELISA). The cell strains were identified by analyzing the number of chromosomes, the heat stability, the acid and alkali, the types and subtypes of immnoglobulin, and its peculiarities and affinities. Through identification, the chromosome number of hybridoma cell strains was from 80 to 100 and the strains formed good hybridomas colonies. The strains' affinity constants were 4.63×109 and 3.75×109 (mol L-1)-1, respectively. At the same time, the McAb secreted was stable to environmental factors, such as, temperature, acid, alkali and so on. The monoclonal antibodies had been obtained and their specificity to porcine adipocyte plasma membrane proteins had been identified.

  7. Improved Detection of Domoic Acid Using Covalently Immobilised Antibody Fragments

    Directory of Open Access Journals (Sweden)

    J. Gerard Wall

    2013-03-01

    Full Text Available Antibody molecules, and antibody fragments in particular, have enormous potential in the development of biosensors for marine monitoring. Conventional immobilisation approaches used in immunoassays typically yield unstable and mostly incorrectly oriented antibodies, however, resulting in reduced detection sensitivities for already low concentration analytes. The 2H12 anti-domoic acid scFv antibody fragment was engineered with cysteine-containing linkers of two different lengths, distal to the antigen binding pocket, for covalent and correctly oriented immobilisation of the scFvs on functionalised solid supports. The Escherichia coli-produced, cysteine-engineered scFvs dimerised in solution and demonstrated similar efficiencies of covalent immobilisation on maleimide-activated plates and minimal non-covalent attachment. The covalently attached scFvs exhibited negligible leaching from the support under acidic conditions that removed almost 50% of the adsorbed wildtype fragment, and IC50s for domoic acid of 270 and 297 ng/mL compared with 1126 and 1482 ng/mL, respectively, for their non-covalently adsorbed counterparts. The expression and immobilisation approach will facilitate the development of stable, reusable biosensors with increased stability and detection sensitivity for marine neurotoxins.

  8. Antipeptide antibody that specifically inhibits insulin receptor autophosphorylation and protein kinase activity

    International Nuclear Information System (INIS)

    Two site-specific antibodies that immunoprecipitate the human insulin receptor have been prepared by immunizing rabbits with chemically synthesized peptides derived from the cDNA-predicted amino acid sequence of the β subunit of the proreceptor. Antibodies to the carboxyl terminus (AbP5) and to a domain around tyrosine-960 (AbP4) specifically recognize the β subunit of the receptor on immunoblots. Both antibodies immunoprecipitated 125I-labeled insulin-receptor complexes and the autophosphorylated receptor. Although neither antibody inhibited insulin binding to the receptor, both insulin-dependent autophosphorylation and exogenous substrate phosphorylation were inhibited by AbP4. Inhibition by AbP4 was dependent upon the phosphorylation state of the receptor; it was not detected when the receptor was autophosphorylated prior to addition of AbP4. AbP4 did not inhibit activity of the related epidermal growth factor (EGF)-receptor tyrosine protein kinase nor did it inhibit the activity of cAMP-dependent kinase or protein kinase C. The observation that an antibody directed to residues 952-967 of the proreceptor neutralizes the protein kinase activity of the β subunit suggest that this region may play a critical role in the function of the hormone-dependent, protein tyrosine-specific kinase activity of the insulin receptor

  9. Protective effects of L-type fatty acid-binding protein (L-FABP) in proximal tubular cells against glomerular injury in anti-GBM antibody-mediated glomerulonephritis

    OpenAIRE

    Kanaguchi, Yasuhiko; Suzuki, Yusuke; Osaki, Ken; Sugaya, Takeshi; Horikoshi, Satoshi; Tomino, Yasuhiko

    2011-01-01

    Background. In glomerulonephritis (GN), an overload of free fatty acids (FFA) bound to albumin in urinary protein may induce oxidative stress in the proximal tubules. Human liver-type fatty acid-binding protein (hL-FABP) expressed in human proximal tubules, but not rodents, participates in intracellular FFA metabolism and exerts anti-oxidative effects on the progression of tubulointerstitial damage. We examined whether tubular enhancement of this anti-oxidative action modulates the progressio...

  10. Simple Method To Prepare Oligonucleotide-Conjugated Antibodies and Its Application in Multiplex Protein Detection in Single Cells.

    Science.gov (United States)

    Gong, Haibiao; Holcomb, Ilona; Ooi, Aik; Wang, Xiaohui; Majonis, Daniel; Unger, Marc A; Ramakrishnan, Ramesh

    2016-01-20

    The diversity of nucleic acid sequences enables genomics studies in a highly multiplexed format. Since multiplex protein detection is still a challenge, it would be useful to use genomics tools for this purpose. This can be accomplished by conjugating specific oligonucleotides to antibodies. Upon binding of the oligonucleotide-conjugated antibodies to their targets, the protein levels can be converted to oligonucleotide levels. In this report we describe a simple method for preparing oligonucleotide-conjugated antibodies and discuss this method's application in oligonucleotide extension reaction (OER) for multiplex protein detection. Conjugation is based on strain-promoted alkyne-azide cycloaddition (the Cu-free click reaction), in which the antibody is activated with a dibenzocyclooctyne (DBCO) moiety and subsequently linked covalently with an azide-modified oligonucleotide. In the functional test, the reaction conditions and purification processes were optimized to achieve maximum yield and best performance. The OER assay employs a pair of antibody binders (two antibodies, each conjugated with its own oligonucleotide) developed for each protein target. The two oligonucleotides contain unique six-base complementary regions at their 3' prime ends to allow annealing and extension by DNA synthesis enzymes to form a DNA template. Following preamplification, the DNA template is detected by qPCR. Distinct oligonucleotide sequences are assigned to different antibody binders to enable multiplex protein detection. When tested using recombinant proteins, some antibody binders, such as those specific to CSTB, MET, EpCAM, and CASP3, had dynamic ranges of 5-6 logs. The antibody binders were also used in a multiplexed format in OER assays, and the binders successfully detected their protein targets in cell lysates, and in single cells in combination with the C1 system. This click reaction-based antibody conjugation procedure is cost-effective, needs minimal hands-on time, and

  11. Limited cross-reactivity of mouse monoclonal antibodies against Dengue virus capsid protein among four serotypes

    Science.gov (United States)

    Noda, Megumi; Masrinoul, Promsin; Punkum, Chaweewan; Pipattanaboon, Chonlatip; Ramasoota, Pongrama; Setthapramote, Chayanee; Sasaki, Tadahiro; Sasayama, Mikiko; Yamashita, Akifumi; Kurosu, Takeshi; Ikuta, Kazuyoshi; Okabayashi, Tamaki

    2012-01-01

    Background Dengue illness is one of the important mosquito-borne viral diseases in tropical and subtropical regions. Four serotypes of dengue virus (DENV-1, DENV-2, DENV-3, and DENV-4) are classified in the Flavivirus genus of the family Flaviviridae. We prepared monoclonal antibodies against DENV capsid protein from mice immunized with DENV-2 and determined the cross-reactivity with each serotype of DENV and Japanese encephalitis virus. Methods and results To clarify the relationship between the cross-reactivity of monoclonal antibodies and the diversity of these viruses, we examined the situations of flaviviruses by analyses of phylogenetic trees. Among a total of 60 prepared monoclonal antibodies specific for DENV, five monoclonal antibodies stained the nuclei of infected cells and were found to be specific to the capsid protein. Three were specific to DENV-2, while the other two were cross-reactive with DENV-2 and DENV-4. No monoclonal antibodies were cross-reactive with all four serotypes. Phylogenetic analysis of DENV amino acid sequences of the capsid protein revealed that DENV-2 and DENV-4 were clustered in the same branch, while DENV-1 and DENV-3 were clustered in the other branch. However, these classifications of the capsid protein were different from those of the envelope and nonstructural 1 proteins. Phylogenetic distances between the four serotypes of DENV were as different as those of other flaviviruses, such as Japanese encephalitis virus and West Nile virus. Large variations in the DENV serotypes were comparable with the differences between species of flavivirus. Furthermore, the diversity of flavivirus capsid protein was much greater than that of envelope and nonstructural 1 proteins. Conclusion In this study, we produced specific monoclonal antibodies that can be used to detect DENV-2 capsid protein, but not a cross-reactive one with all serotypes of DENV capsid protein. The high diversity of the DENV capsid protein sequence by phylogenetic

  12. Targeted in vivo inhibition of specific protein-protein interactions using recombinant antibodies.

    Directory of Open Access Journals (Sweden)

    Matej Zábrady

    Full Text Available With the growing availability of genomic sequence information, there is an increasing need for gene function analysis. Antibody-mediated "silencing" represents an intriguing alternative for the precise inhibition of a particular function of biomolecules. Here, we describe a method for selecting recombinant antibodies with a specific purpose in mind, which is to inhibit intrinsic protein-protein interactions in the cytosol of plant cells. Experimental procedures were designed for conveniently evaluating desired properties of recombinant antibodies in consecutive steps. Our selection method was successfully used to develop a recombinant antibody inhibiting the interaction of ARABIDOPSIS HISTIDINE PHOSPHOTRANSFER PROTEIN 3 with such of its upstream interaction partners as the receiver domain of CYTOKININ INDEPENDENT HISTIDINE KINASE 1. The specific down-regulation of the cytokinin signaling pathway in vivo demonstrates the validity of our approach. This selection method can serve as a prototype for developing unique recombinant antibodies able to interfere with virtually any biomolecule in the living cell.

  13. Synthetic Peptide Immunogens Elicit Polyclonal and Monoclonal Antibodies Specific for Linear Epitopes in the D Motifs of Staphylococcus aureus Fibronectin-Binding Protein, Which Are Composed of Amino Acids That Are Essential for Fibronectin Binding

    OpenAIRE

    Huesca, Mario; Sun, Qing; Peralta, Robert; Shivji, Gulnar M.; Sauder, Daniel N.; McGavin, Martin J.

    2000-01-01

    A fibronectin (Fn)-binding adhesin of Staphylococcus aureus contains three tandem 37- or 38-amino-acid motifs (D1, D2, and D3), which function to bind Fn. Plasma from patients with S. aureus infections contain antibodies that preferentially recognize ligand induced binding sites in the D motifs and do not inhibit Fn binding (F. Casolini, L. Visai, D. Joh, P. G. Conaldi, A. Toniolo, M. Höök, and P. Speziale, Infect. Immun. 66:5433–5442, 1998). To eliminate the influence of Fn binding on antibo...

  14. Antibody glycosylation and its impact on the pharmacokinetics and pharmacodynamics of monoclonal antibodies and Fc-fusion proteins.

    Science.gov (United States)

    Liu, Liming

    2015-06-01

    Understanding the impact of glycosylation and keeping a close control on glycosylation of product candidates are required for both novel and biosimilar monoclonal antibodies (mAbs) and Fc-fusion protein development to ensure proper safety and efficacy profiles. Most therapeutic mAbs are of IgG class and contain a glycosylation site in the Fc region at amino acid position 297 and, in some cases, in the Fab region. For Fc-fusion proteins, glycosylation also frequently occurs in the fusion partners. Depending on the expression host, glycosylation patterns in mAb or Fc-fusions can be significantly different, thus significantly impacting the pharmacokinetics (PK) and pharmacodynamics (PD) of mAbs. Glycans that have a major impact on PK and PD of mAb or Fc-fusion proteins include mannose, sialic acids, fucose (Fuc), and galactose (Gal). Mannosylated glycans can impact the PK of the molecule, leading to reduced exposure and potentially lower efficacy. The level of sialic acid, N-acetylneuraminic acid (NANA), can also have a significant impact on the PK of Fc-fusion molecules. Core Fuc in the glycan structure reduces IgG antibody binding to IgG Fc receptor IIIa relative to IgG lacking Fuc, resulting in decreased antibody-dependent cell-mediated cytotoxicity (ADCC) activities. Glycoengineered Chinese hamster ovary (CHO) expression systems can produce afucosylated mAbs that have increased ADCC activities. Terminal Gal in a mAb is important in the complement-dependent cytotoxicity (CDC) in that lower levels of Gal reduce CDC activity. Glycans can also have impacts on the safety of mAb. mAbs produced in murine myeloma cells such as NS0 and SP2/0 contain glycans such as Galα1-3Galβ1-4N-acetylglucosamine-R and N-glycolylneuraminic acid (NGNA) that are not naturally present in humans and can be immunogenic when used as therapeutics. PMID:25872915

  15. Response of early-weaned pigs to an enterotoxigenic Escherichia coli (K88) challenge when fed diets containing spray-dried porcine plasma or pea protein isolate plus egg yolk antibody, zinc oxide, fumaric acid, or antibiotic.

    Science.gov (United States)

    Owusu-Asiedu, A; Nyachoti, C M; Marquardt, R R

    2003-07-01

    The effect of feeding diets containing either spray-dried porcine plasma (SDPP) or pea protein-isolate (PPI) supplemented with either egg yolk antibodies (EYA) from hens immunized with enterotoxigenic Escherichia coli (ETEC) (K88 and F18) antigens, ZnO, fumaric acid (FA), or carbadox (AB) on pig performance, incidence of scours, and gut morphology was studied in a 14-d experiment. Ninety 10-d-old weaned pigs were assigned to six dietary treatments in a completely randomized design to give five pens per treatment with three pigs per pen. The diets were SDPP without EYA (SDPP - EYA), PPI without EYA (PPI - EYA), PPI with EYA (PPI + EYA), PPI with ZnO (PPI + ZnO), PPI with FA (PPI + FA), or PPI with AB (PPI + AB). Diets were formulated to similar nutrient levels, with AB, EYA, FA, and ZnO at 0.25, 0.5, 2.0, and 0.4% of the diet, respectively. Pigs were weighed and bled on d 0, 7, and 14 to determine plasma urea N (PUN). Pigs were orally challenged with a 6-mL dose of 10(10) cfu/mL ETEC (K88) on d 7. On d 14, three pigs per treatment were killed to obtain sections of the small intestine for histological measurements. Weekly feed intake, BW changes, and gain:feed were determined. Incidence of scours and scour scores were monitored and fecal swabs were taken before and after ETEC challenge for PCR test to detect ETEC (K88). Feeding SDPP or supplementing PPI-based diets with EYA, ZnO, FA, or AB did not affect (P > 0.05) ADG, ADFI (as-fed basis), or gain:feed throughout the study. However, pigs fed PPI - EYA tended to have lower (P = 0.08) ADFI during wk 2 (137.9 g/d) and lower (P pigs 8 h after the ETEC challenge, it lasted only 3 to 5 d in pigs fed SDPP or PPI supplemented with EYA, ZnO, FA, or AB. Pigs fed PPI - EYA continued to have severe diarrhea, resulting in 40% mortality vs. 13% or less in the other groups. The PCR results showed that 81% of PPI-fed pigs continued to shed ETEC K88 7 d after ETEC challenge. Pigs fed PPI-EYA had shorter villi (P pigs to efficiently

  16. Antibody-protein interactions: benchmark datasets and prediction tools evaluation

    Directory of Open Access Journals (Sweden)

    Ponomarenko Julia V

    2007-10-01

    Full Text Available Abstract Background The ability to predict antibody binding sites (aka antigenic determinants or B-cell epitopes for a given protein is a precursor to new vaccine design and diagnostics. Among the various methods of B-cell epitope identification X-ray crystallography is one of the most reliable methods. Using these experimental data computational methods exist for B-cell epitope prediction. As the number of structures of antibody-protein complexes grows, further interest in prediction methods using 3D structure is anticipated. This work aims to establish a benchmark for 3D structure-based epitope prediction methods. Results Two B-cell epitope benchmark datasets inferred from the 3D structures of antibody-protein complexes were defined. The first is a dataset of 62 representative 3D structures of protein antigens with inferred structural epitopes. The second is a dataset of 82 structures of antibody-protein complexes containing different structural epitopes. Using these datasets, eight web-servers developed for antibody and protein binding sites prediction have been evaluated. In no method did performance exceed a 40% precision and 46% recall. The values of the area under the receiver operating characteristic curve for the evaluated methods were about 0.6 for ConSurf, DiscoTope, and PPI-PRED methods and above 0.65 but not exceeding 0.70 for protein-protein docking methods when the best of the top ten models for the bound docking were considered; the remaining methods performed close to random. The benchmark datasets are included as a supplement to this paper. Conclusion It may be possible to improve epitope prediction methods through training on datasets which include only immune epitopes and through utilizing more features characterizing epitopes, for example, the evolutionary conservation score. Notwithstanding, overall poor performance may reflect the generality of antigenicity and hence the inability to decipher B-cell epitopes as an

  17. Amino acid consumption in naïve and recombinant CHO cell cultures: producers of a monoclonal antibody

    OpenAIRE

    Carrillo-Cocom, L. M.; Genel-Rey, T.; Araíz-Hernández, D.; López-Pacheco, F.; López-Meza, J.; Rocha-Pizaña, M. R.; Ramírez-Medrano, A.; Alvarez, M. M.

    2014-01-01

    Most commercial media for mammalian cell culture are designed to satisfy the amino acid requirements for cell growth, but not necessarily those for recombinant protein production. In this study, we analyze the amino acid consumption pattern in naïve and recombinant Chinese hamster ovary (CHO) cell cultures. The recombinant model we chose was a CHO-S cell line engineered to produce a monoclonal antibody. We report the cell concentration, product concentration, and amino acid concentration prof...

  18. [Characterization of a panel of monoclonal antibodies to hepatitis C NS3 recombinant protein ].

    Science.gov (United States)

    Abdulmedzhidova, A G; Masalova, O V; Atanadze, S N; Ulanova, T I; Burkov, A N; Khudiakov, Iu E; Fields, H; Kushch, A A

    2002-01-01

    Recombinant protein rNS3 imitating helicase region (1356-1459 amino acid residues) of hepatitis C virus (HCV) was expressed in E. coli cells and used for BALB/c mice immunization. Seven hybrydoma clones producing monoclonal antibodies (MAbs) to rHS3 were obtained. All MAbs reacted in ELISA with NS3 protein from Murex anti-HCV Version III and in immunoblotting from RIBA 3. These MAbs detect 5 individual epitopes, 4 of which were conformational and 1 discontinuous. All MAbs could compete for rNS3 binding with serum antibodies from patients with chronic hepatitis C, which suggests that these MAbs can recognize the natural HCV NS3 protein.

  19. Localization of somatostatin receptors at the light and electron microscopical level by using antibodies raised against fusion proteins

    DEFF Research Database (Denmark)

    Helboe, Lone; Møller, Morten

    2000-01-01

    Somatostatin, antibodies against somatostatin receptors, hypothalamus, Müller cells, fusion protein technique......Somatostatin, antibodies against somatostatin receptors, hypothalamus, Müller cells, fusion protein technique...

  20. Production and characterization of antibodies against irradiated human erythrocytes membrane proteins

    International Nuclear Information System (INIS)

    Gamma irradiation affects people in several situations, with few if any sensitive biological assay of its action. Nucleic acids and proteins are affected by radiation, but only the former was used in most dosimetric techniques. The irradiation of proteins promotes structural modifications attributed to free radicals from water radiolysis. Theoretically, antibodies induced by irradiated proteins could recognize these radical-related new epitopes, allowing their use as a probe. Human erythrocyte membrane proteins (HEMP), few and well defined molecules, are certainly exposed to radiation, being the ideal target. With this rationale, we study the production of antibodies in mice immunized with 60 Co irradiated HEMPs. Menbranes from hypotonic lysis with differential centrifugation of A+ erythrocytes, were irradiated in a Gammacell 220 with 400, 800 and 1600 Gy, and used as immunogen for Balb/c mice, after SDS-PAGE. Irradiated HEMP induced antibodies recognize only irradiated human erthrocytes in an intact cell indirect immunofluorescence assay (ICIIFA). When used in Wester-blot against non-irradiated HEMPs, those sera recognize most proteins, suggesting a pool of abs directed both to native, as detected by Western Blot, or irradiated, as detected by ICIFA, HEMPs. Those data confirmed our assumptions, allowing the use of those abs in the search for a method of biological dosimetry. (author). 18 refs., 3 figs

  1. A recombinant single chain antibody interleukin-2 fusion protein.

    OpenAIRE

    Savage, P; So, A; Spooner, R A; Epenetos, A. A.

    1993-01-01

    Recombinant interleukin-2 (rIL-2) therapy has been shown to be of value in the treatment of some cases of melanoma and renal cell carcinoma. However its use can be limited by severe systemic toxicity. Targeting rIL-2 to the tumour should improve the anti-tumour immune response and decrease the systemic toxicity. With this aim we have employed recombinant DNA techniques to construct a single chain antibody interleukin-2 fusion protein (SCA-IL-2). The protein used in this model system comprises...

  2. Comprehensive Mapping Antigenic Epitopes of NS1 Protein of Japanese Encephalitis Virus with Monoclonal Antibodies.

    Directory of Open Access Journals (Sweden)

    Rong-Hong Hua

    Full Text Available Japanese encephalitis virus (JEV non-structural protein 1 (NS1 contributes to virus replication and elicits protective immune responses during infection. JEV NS1-specific antibody responses could be a target in the differential diagnosis of different flavivirus infections. However, the epitopes on JEV NS1 are poorly characterized. The present study describes the full mapping of linear B-cell epitopes in JEV NS1. We generated eleven NS1-specific monoclonal antibodies from mice immunized with recombinant NS1. For epitope mapping of monoclonal antibodies, a set of 51 partially-overlapping peptides covering the entire NS1 protein were expressed with a GST-tag and then screened using monoclonal antibodies. Through enzyme-linked immunosorbent assay (ELISA, five linear epitope-containing peptides were identified. By sequentially removing amino acid residues from the carboxy and amino terminal of peptides, the minimal units of the five linear epitopes were identified and confirmed using monoclonal antibodies. Five linear epitopes are located in amino acids residues (5AIDITRK(11, (72RDELNVL(78, (251KSKHNRREGY(260, (269DENGIVLD(276, and (341DETTLVRS(348. Furthermore, it was found that the epitopes are highly conserved among JEV strains through sequence alignment. Notably, none of the homologous regions on NS1 proteins from other flaviviruses reacted with the MAbs when they were tested for cross-reactivity, and all five epitope peptides were not recognized by sera against West Nile virus or Dengue virus. These novel virus-specific linear B-cell epitopes of JEV NS1 would benefit the development of new vaccines and diagnostic assays.

  3. Monoclonal antibody-escape variant of dengue virus serotype 1: Genetic composition and envelope protein expression.

    Science.gov (United States)

    Chem, Y K; Chua, K B; Malik, Y; Voon, K

    2015-06-01

    Monoclonal antibody-escape variant of dengue virus type 1 (MabEV DEN-1) was discovered and isolated in an outbreak of dengue in Klang Valley, Malaysia from December 2004 to March 2005. This study was done to investigate whether DEN152 (an isolate of MabEV DEN-1) is a product of recombination event or not. In addition, the non-synonymous mutations that correlate with the monoclonal antibody-escape variant were determined in this study. The genomes of DEN152 and two new DEN-1 isolates, DENB04 and DENK154 were completely sequenced, aligned, and compared. Phylogenetic tree was plotted and the recombination event on DEN152 was investigated. DEN152 is sub-grouped under genotype I and is closely related genetically to a DEN-1 isolated in Japan in 2004. DEN152 is not a recombinant product of any parental strains. Four amino acid substitutions were unique only to DEN 152. These amino acid substitutions were (Ser)[326](Leu), (Ser)[340](Leu) at the deduced E protein, (Ile)[250](Thr) at NS1 protein, and (Thr)[41](Ser) at NS5 protein. Thus, DEN152 is an isolate of the emerging monoclonal antibody-escape variant DEN-1 that escaped diagnostic laboratory detection. PMID:26691263

  4. Computational structural analysis of an anti-l-amino acid antibody and inversion of its stereoselectivity

    OpenAIRE

    Ranieri, Daniel I.; Hofstetter, Heike; Hofstetter, Oliver

    2009-01-01

    The binding site of a monoclonal anti-l-amino acid antibody was modeled using the program SWISS-MODEL. Docking experiments with the enantiomers of phenylalanine revealed that the antibody interacts with l-phenylalanine via hydrogen bonds and hydrophobic contacts, whereas the d-enantiomer is rejected due to steric hindrance. Comparison of the sequences of this antibody and an anti-d-amino acid antibody indicates that both immunoglobulins derived from the same germline progenitor. Substitution ...

  5. Circulating protein and antibody biomarker for personalized cancer immunotherapy.

    Science.gov (United States)

    Yuan, Jianda

    2016-01-01

    Immune checkpoint blockade therapies are revolutionizing standard cancer treatments. Immune checkpoint inhibitors likely function to enhance the tumor specific antigen response in order to achieve favorable clinical outcomes. Thus, continuous efforts to identify the common tumor-specific antigens are essential for the broad clinical application of these therapies. Several immunoproteomics approaches have been used in order to screen for this specificity. In a recent article from Jhaveri and colleagues published in the February issue of Cancer Immunology Research, antibody biomarkers were screened in pancreatic cancer patients who received allogeneic, granulocyte-macrophage colony stimulating factor-secreting pancreatic cancer vaccine (GVAX) by using a serum antibody-based SILAC immunoprecipitation (SASI) approach. Using this assay, several new tumor antigens (MYPT1, PSMC5 and TRFR) were identified that were found to have significantly different expression in tumors compared with normal tissue. Moreover, patients with detectable antibodies showed improved disease-free survival after GVAX therapy. These targets need to be further validated to determine the full spectrum of tumor antigen immunogencity and their potential clinical application. In addition to antibodies, circulating protein, DNA and RNA in peripheral blood are under clinical investigation as liquid biopsies and have the potential to provide guidance for future personalized cancer immunotherapy.

  6. A sequence in subdomain 2 of DBL1α of Plasmodium falciparum erythrocyte membrane protein 1 induces strain transcending antibodies.

    Directory of Open Access Journals (Sweden)

    Karin Blomqvist

    Full Text Available Immunity to severe malaria is the first level of immunity acquired to Plasmodium falciparum. Antibodies to the variant antigen PfEMP1 (P. falciparum erythrocyte membrane protein 1 present at the surface of the parasitized red blood cell (pRBC confer protection by blocking microvascular sequestration. Here we have generated antibodies to peptide sequences of subdomain 2 of PfEMP1-DBL1α previously identified to be associated with severe or mild malaria. A set of sera generated to the amino acid sequence KLQTLTLHQVREYWWALNRKEVWKA, containing the motif ALNRKE, stained the live pRBC. 50% of parasites tested (7/14 were positive both in flow cytometry and immunofluorescence assays with live pRBCs including both laboratory strains and in vitro adapted clinical isolates. Antibodies that reacted selectively with the sequence REYWWALNRKEVWKA in a 15-mer peptide array of DBL1α-domains were also found to react with the pRBC surface. By utilizing a peptide array to map the binding properties of the elicited anti-DBL1α antibodies, the amino acids WxxNRx were found essential for antibody binding. Complementary experiments using 135 degenerate RDSM peptide sequences obtained from 93 Ugandan patient-isolates showed that antibody binding occurred when the amino acids WxLNRKE/D were present in the peptide. The data suggests that the ALNRKE sequence motif, associated with severe malaria, induces strain-transcending antibodies that react with the pRBC surface.

  7. Quantitation of glial fibrillary acidic protein in human brain tumours

    DEFF Research Database (Denmark)

    Rasmussen, S; Bock, E; Warecka, K;

    1980-01-01

    The glial fibrillary acidic protein (GFA) content of 58 human brain tumours was determined by quantitative immunoelectrophoresis, using monospecific antibody against GFA. Astrocytomas, glioblastomas, oligodendrogliomas, spongioblastomas, ependymomas and medulloblastomas contained relatively high...... amounts of GFA, up to 85 times the concentration in parietal grey substance of normal human brain. GFA was not found in neurinomas, meningiomas, adenomas of the hypophysis, or in a single case of metastasis of adenocarcinoma. Non-glial tumours of craniopharyngioma and haemangioblastoma were infiltrated by...

  8. Human Protein and Amino Acid Requirements.

    Science.gov (United States)

    Hoffer, L John

    2016-05-01

    Human protein and amino acid nutrition encompasses a wide, complex, frequently misunderstood, and often contentious area of clinical research and practice. This tutorial explains the basic biochemical and physiologic principles that underlie our current understanding of protein and amino acid nutrition. The following topics are discussed: (1) the identity, measurement, and essentiality of nutritional proteins; (2) the definition and determination of minimum requirements; (3) nutrition adaptation; (4) obligatory nitrogen excretion and the minimum protein requirement; (5) minimum versus optimum protein intakes; (6) metabolic responses to surfeit and deficient protein intakes; (7) body composition and protein requirements; (8) labile protein; (9) N balance; (10) the principles of protein and amino acid turnover, including an analysis of the controversial indicator amino acid oxidation technique; (11) general guidelines for evaluating protein turnover articles; (12) amino acid turnover versus clearance; (13) the protein content of hydrated amino acid solutions; (14) protein requirements in special situations, including protein-catabolic critical illness; (15) amino acid supplements and additives, including monosodium glutamate and glutamine; and (16) a perspective on the future of protein and amino acid nutrition research. In addition to providing practical information, this tutorial aims to demonstrate the importance of rigorous physiologic reasoning, stimulate intellectual curiosity, and encourage fresh ideas in this dynamic area of human nutrition. In general, references are provided only for topics that are not well covered in modern textbooks. PMID:26796095

  9. Characterization of monoclonal antibodies against waterfowl parvoviruses VP3 protein

    Directory of Open Access Journals (Sweden)

    Yin Xiuchen

    2012-11-01

    Full Text Available Abstract Background The VP3 protein of goose parvovirus (GPV or Muscovy duck parvovirus (MDPV, a major structural protein, can induce neutralizing antibodies in geese and ducks, but monoclonal antibodies (MAbs against VP3 protein has never been characterized. Results Three hybridoma cell lines secreting anti-GPV VP3 MAbs were obtained and designated 4A8, 4E2, and 2D5. Immunoglobulin subclass tests differentiated them as IgG2b (4A8 and 4E2 and IgG2a (2D5. Dot blotting assays showed that three MAbs reacted with His-VP3 protein in a conformation-independent manner. A competitive binding assay indicated that the MAbs delineated two epitopes, A and B of VP3. Immunofluorescence assay showed that MAbs 4A8, 4E2, and 2D5 could specifically bind to goose embryo fibroblast cells (GEF or duck fibroblast cells (DEF infected with GPV and MDPV. Dot blotting also showed that the MAbs recognized both nature GPV and MDPV antigen. Western blotting confirmed that the MAbs recognized VP3 proteins derived from purified GPV and MDPV particles. The MAbs 4A8 and 2D5 had universal reactivity to heterologous GPV and MDPV tested in an antigen-capture enzyme-linked immunosorbent assay. Conclusions Preparation and characterization of these the MAbs suggests that they may be useful for the development of a MAb-capture ELISA for rapid detection of both GPV and MDPV. Virus isolation and PCR are reliable for detecting GPV and MDPV infection, but these procedures are laborious, time-consuming, and requiring instruments. These diagnosis problems highlight the ongoing demand for rapid, reproducible, and automatic methods for the sensitive detection of both GPV and MDPV infection.

  10. Referencing cross-reactivity of detection antibodies for protein array experiments.

    Science.gov (United States)

    Lemass, Darragh; O'Kennedy, Richard; Kijanka, Gregor S

    2016-01-01

    Protein arrays are frequently used to profile antibody repertoires in humans and animals. High-throughput protein array characterisation of complex antibody repertoires requires a platform-dependent, lot-to-lot validation of secondary detection antibodies. This article details the validation of an affinity-isolated anti-chicken IgY antibody produced in rabbit and a goat anti-rabbit IgG antibody conjugated with alkaline phosphatase using protein arrays consisting of 7,390 distinct human proteins. Probing protein arrays with secondary antibodies in absence of chicken serum revealed non-specific binding to 61 distinct human proteins. The cross-reactivity of the tested secondary detection antibodies points towards the necessity of platform-specific antibody characterisation studies for all secondary immunoreagents. Secondary antibody characterisation using protein arrays enables generation of reference lists of cross-reactive proteins, which can be then excluded from analysis in follow-up experiments. Furthermore, making such cross-reactivity lists accessible to the wider research community may help to interpret data generated by the same antibodies in applications not related to protein arrays such as immunoprecipitation, Western blots or other immunoassays. PMID:27335636

  11. Characterization of antibodies directed against the Ankrd2 human muscle protein

    Directory of Open Access Journals (Sweden)

    Kojić Snežana

    2009-01-01

    Full Text Available In order to study the function of the Ankrd2 protein, for which commercial antibodies are not available, we report the production and analysis of polyclonal antibodies to full-length Ankrd2 and its C-terminal and N-terminal regions, as well as a monoclonal antibody to the C-terminus of the protein. Epitope mapping making use of recombinant deletion mutants showed that an epitope located in region 323-333 aa of Ankrd2 is detected by the monoclonal antibody. The high specificity of all four anti-Ankrd2 antibodies for recombinant and endogenous Ankrd2 protein is also demon­strated.

  12. Small antibody-like proteins with prescribed ligand specificities derived from the lipocalin fold

    Science.gov (United States)

    Beste, Gerald; Schmidt, Frank S.; Stibora, Thomas; Skerra, Arne

    1999-01-01

    We demonstrate that the ligand pocket of a lipocalin from Pieris brassicae, the bilin-binding protein (BBP), can be reshaped by combinatorial protein design such that it recognizes fluorescein, an established immunological hapten. For this purpose 16 residues at the center of the binding site, which is formed by four loops on top of an eight-stranded β-barrel, were subjected to random mutagenesis. Fluorescein-binding BBP variants were then selected from the mutant library by bacterial phage display. Three variants were identified that complex fluorescein with high affinity, exhibiting dissociation constants as low as 35.2 nM. Notably, one of these variants effects almost complete quenching of the ligand fluorescence, similarly as an anti-fluorescein antibody. Detailed ligand-binding studies and site-directed mutagenesis experiments indicated (i) that the molecular recognition of fluorescein is specific and (ii) that charged residues at the center of the pocket are responsible for tight complex formation. Sequence comparison of the BBP variants directed against fluorescein with the wild-type protein and with further variants that were selected against several other ligands revealed that all of the randomized amino acid positions are variable. Hence, a lipocalin can be used for generating molecular pockets with a diversity of shapes. We term this class of engineered proteins “anticalins.” Their one-domain scaffold makes them a promising alternative to antibodies to create a stable receptor protein for a ligand of choice. PMID:10051566

  13. Immunological characteristics of outer membrane protein omp31 of goat Brucella and its monoclonal antibody.

    Science.gov (United States)

    Zheng, W Y; Wang, Y; Zhang, Z C; Yan, F

    2015-10-05

    We examined the immunological characteristics of outer membrane protein omp31 of goat Brucella and its monoclonal antibody. Genomic DNA from the M5 strain of goat Brucella was amplified by polymerase chain reaction and cloned into the prokaryotic expression vector pGEX-4T-1. The expression and immunological characteristics of the fusion protein GST-omp31 were subjected to preliminary western blot detection with goat Brucella rabbit immune serum. The Brucella immunized BALB/c mouse serum was detected using purified protein. The high-potency mouse splenocytes and myeloma Sp2/0 cells were fused. Positive clones were screened by enzyme-linked immunosorbent assay to establish a hybridoma cell line. Mice were inoculated intraperitoneally with hybridoma cells to prepare ascites. The mAb was purified using the n-caprylic acid-ammonium sulfate method. The characteristics of mAb were examined using western blotting and enzyme-linked immunosorbent assay. A 680-base pair band was observed after polymerase chain reaction. Enzyme digestion identification and sequencing showed that the pGEX-4T-1-omp31 prokaryotic expression vector was successfully established; a target band of approximately 57 kDa with an apparent molecular weight consistent with the size of the target fusion protein. At 25°C, the expression of soluble expression increased significantly; the fusion protein GST-omp31 was detected by western blotting. Anti-omp31 protein mAb was obtained from 2 strains of Brucella. The antibody showed strong specificity and sensitivity and did not cross-react with Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Mycobacterium tuberculosis, or Bacillus pyocyaneus. The pGEX-4T-1-omp31 prokaryotic expression vector was successfully established and showed good immunogenicity. The antibody also showed strong specificity and good sensitivity.

  14. Immunological characteristics of outer membrane protein omp31 of goat Brucella and its monoclonal antibody.

    Science.gov (United States)

    Zheng, W Y; Wang, Y; Zhang, Z C; Yan, F

    2015-01-01

    We examined the immunological characteristics of outer membrane protein omp31 of goat Brucella and its monoclonal antibody. Genomic DNA from the M5 strain of goat Brucella was amplified by polymerase chain reaction and cloned into the prokaryotic expression vector pGEX-4T-1. The expression and immunological characteristics of the fusion protein GST-omp31 were subjected to preliminary western blot detection with goat Brucella rabbit immune serum. The Brucella immunized BALB/c mouse serum was detected using purified protein. The high-potency mouse splenocytes and myeloma Sp2/0 cells were fused. Positive clones were screened by enzyme-linked immunosorbent assay to establish a hybridoma cell line. Mice were inoculated intraperitoneally with hybridoma cells to prepare ascites. The mAb was purified using the n-caprylic acid-ammonium sulfate method. The characteristics of mAb were examined using western blotting and enzyme-linked immunosorbent assay. A 680-base pair band was observed after polymerase chain reaction. Enzyme digestion identification and sequencing showed that the pGEX-4T-1-omp31 prokaryotic expression vector was successfully established; a target band of approximately 57 kDa with an apparent molecular weight consistent with the size of the target fusion protein. At 25°C, the expression of soluble expression increased significantly; the fusion protein GST-omp31 was detected by western blotting. Anti-omp31 protein mAb was obtained from 2 strains of Brucella. The antibody showed strong specificity and sensitivity and did not cross-react with Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Mycobacterium tuberculosis, or Bacillus pyocyaneus. The pGEX-4T-1-omp31 prokaryotic expression vector was successfully established and showed good immunogenicity. The antibody also showed strong specificity and good sensitivity. PMID:26505344

  15. Designed Amino Acid Feed in Improvement of Production and Quality Targets of a Therapeutic Monoclonal Antibody.

    Directory of Open Access Journals (Sweden)

    Fatemeh Torkashvand

    Full Text Available Cell culture feeds optimization is a critical step in process development of pharmaceutical recombinant protein production. Amino acids are the basic supplements of mammalian cell culture feeds with known effect on their growth promotion and productivity. In this study, we reported the implementation of the Plackett-Burman (PB multifactorial design to screen the effects of amino acids on the growth promotion and productivity of a Chinese hamster ovary DG-44 (CHO-DG44 cell line producing bevacizumab. After this screening, the amino acid combinations were optimized by the response surface methodology (RSM to determine the most effective concentration in feeds. Through this strategy, the final monoclonal antibody (mAb titre was enhanced by 70%, compared to the control group. For this particular cell line, aspartic acid, glutamic acid, arginine and glycine had the highest positive effects on the final mAb titre. Simultaneously, the impact of the designed amino acid feed on some critical quality attributes of bevacizumab was examined in the group with highest productivity. The product was analysed for N-glycan profiles, charge variant distribution, and low molecular weight forms. The results showed that the target product quality has been improved using this feeding strategy. It was shown how this strategy could significantly diminish the time and number of experiments in identifying the most effective amino acids and related concentrations in target product enhancement. This model could be successfully applied to other components of culture media and feeds.

  16. Discovery of functional monoclonal antibodies targeting G-protein-coupled receptors and ion channels.

    Science.gov (United States)

    Wilkinson, Trevor C I

    2016-06-15

    The development of recombinant antibody therapeutics is a significant area of growth in the pharmaceutical industry with almost 50 approved monoclonal antibodies on the market in the US and Europe. Despite this growth, however, certain classes of important molecular targets have remained intractable to therapeutic antibodies due to complexity of the target molecules. These complex target molecules include G-protein-coupled receptors and ion channels which represent a large potential target class for therapeutic intervention with monoclonal antibodies. Although these targets have typically been addressed by small molecule approaches, the exquisite specificity of antibodies provides a significant opportunity to provide selective modulation of these target proteins. Given this opportunity, substantial effort has been applied to address the technical challenges of targeting these complex membrane proteins with monoclonal antibodies. In this review recent progress made in the strategies for discovery of functional monoclonal antibodies for these challenging membrane protein targets is addressed. PMID:27284048

  17. Monoclonal antibodies against NS1 protein of Goose parvovirus.

    Science.gov (United States)

    Qiu, Zheng; Tian, Wei; Yu, Tianfei; Li, Li; Ma, Bo; Wang, Junwei

    2012-04-01

    In the present study, monoclonal antibodies (MAbs) against NS1 protein of Goose parvovirus (GPV) were generated. The secreted MAbs were obtained by fusing mouse myeloma cells and spleen cells of BALB/c mice, which were immunized with the plasmid pcDNA3.1-GPV-NS1 and recombinant protein of GPV-NS1. With indirect ELISA, six hybridoma cell lines against GPV-NS1 were screened. The subtypes of the two MAbs were IgG2a; the others were IgM. The light chain was κ. Western blot analysis showed that six MAbs reacted with recombinant protein GPV-NS1. GPV-NS1 was dissected into 15 overlapping epitopes, which were used to react with MAbs in Western blot. Results showed that six MAbs recognized NS1 protein linear B-cell epitopes located at the C-terminus 453-514 aa, 485-542 aa, and 533-598 aa.

  18. Polyclonal antibody against the DPV UL46M protein can be a diagnostic candidate

    Directory of Open Access Journals (Sweden)

    Jia Renyong

    2010-04-01

    Full Text Available Abstract Background The duck plague virus (DPV UL46 protein (VP11/12 is a 739-amino acid tegument protein encoded by the UL46 gene. We analyzed the amino acid sequence of UL46 using bioinformatics tools and defined the main antigenic domains to be between nucleotides 700-2,220 in the UL46 sequence. This region was designated UL46M. The DPV UL46 and UL46M genes were both expressed in Escherichia coli Rosetta (DE3 induced by isopropy1-β-D-thiogalactopyranoside (IPTG following polymerase chain reaction (PCR amplification and subcloning into the prokaryotic expression vector pET32a(+. The recombinant proteins were purified using a Ni-NTA spin column and used to generate the polyclonal antibody against UL46 and UL46M in New Zealand white rabbits. The titer was then tested using enzyme-linked immunosorbent assay (ELISA and agar diffusion reaction, and the specificity was tested by western blot analysis. Subsequently, we established Dot-ELISA using the polyclonal antibody and applied it to DPV detection. Results In our study, the DPV UL46M fusion protein, with a relative molecular mass of 79 kDa, was expressed in E. coli Rosetta (DE3. Expression of the full UL46 gene failed, which was consistent with the results from the bioinformatic analysis. The expressed product was directly purified using Ni-NTA spin column to prepare the polyclonal antibody against UL46M. The titer of the anti-UL46M antisera was over 1:819,200 as determined by ELISA and 1:8 by agar diffusion reaction. Dot-ELISA was used to detect DPV using a 1:60 dilution of anti-UL46M IgG and a 1:5,000 dilution of horseradish peroxidase (HRP-labeled goat anti-rabbit IgG. Conclusions The anti-UL46M polyclonal antibody reported here specifically identifies DPV, and therefore, it is a promising diagnostic tool for DPV detection in animals. UL46M and the anti-UL46M antibody can be used for further clinical examination and research of DPV.

  19. Effects of Monoclonal Antibody Against Adipocyte-Specific Membrane Protein on Lipid Metabolism in Pigs

    Institute of Scientific and Technical Information of China (English)

    GAO Shi-zheng; LIU Ling-yun; ZHAO Su-mei; HU Hong-mei; GE Chang-rong; LIU Yong-gang; ZHANG Xi

    2008-01-01

    This study was to investigate the regulation of monoclonal antibodies against adipocyte membrane proteins(McAb)on lipid metabolism in pigs.Forty Landrace x Saba pigs were randomly divided into eight groups;the control group was given 10 mL saline and the treat groups were given monoclonal antibody against adipocyte-specific membrane protein with 0.10 0.5,and 1.0 mg kg-1 body weight at 15 and 60 kg body weight,respectively,by intraperitoneal injection.The results showed that McAb could increase,significantly,serum lipoprotein lipase activity and reduce serum nonesterified fatty acid(NEFA)content.Meanwhile,McAb increased content of serum lipid,triglyceride(TG),cholesterol(CHO),high density lipoprotein(HDL),and low density lipoprotein(LDL) both at 15 and 60 kg body weight.However,McAb affected more significantly the lipid metabolism at 15 kg body weight than at 60 kg body weight.Moreover,this effect of McAb on lipid metabolism exhibited dose-dependent effect.These results suggested that this monoclonal antibody increased lipase activity,promoted lipolysis,and utilization of lipid so that McAb could be applied to restrain excessive fat deposition in porcine production through the regulation of fat metabolism.

  20. Improved method to raise polyclonal antibody using enhanced green fluorescent protein transgenic mice

    Institute of Scientific and Technical Information of China (English)

    Jianke Ren; Long Wang; Guoxiang Liu; Wen Zhang; Zhejin Sheng; Zhugang Wang; Jian Fei

    2008-01-01

    Recombinant fusion protein is widely used as an antigen to raise antibodies against the epitope of a target protein. However, the concomitant anticarrier antibody in resulting antiserum reduces the production of the desired antibody and brings about unwanted non-specific immune reactions. It is proposed that the carrier protein transgenic animal could be used to solve this problem. To validate this hypothesis, enhanced green fluorescent protein (EGFP) transgenic mice were produced. By immunizing the mice with fusion protein His6HAtag-EGFP, we showed that the antiserum from the transgenic mice had higher titer antibody against His6HA tag and lower titer antibody against EGFP compared with that from wild-type mice. Therefore, this report describes an improved method to raise high titer antipeptide polyclonal antibody using EGFP transgenic mice that could have application potential in antibodypreparation.

  1. Nucleic acid encoding DS-CAM proteins and products related thereto

    Energy Technology Data Exchange (ETDEWEB)

    Korenberg, Julie R.

    2005-11-01

    In accordance with the present invention, there are provided Down Syndrome-Cell Adhesion Molecule (DS-CAM) proteins. Nucleic acid sequences encoding such proteins and assays employing same are also disclosed. The invention DS-CAM proteins can be employed in a variety of ways, for example, for the production of anti-DS-CAM antibodies thereto, in therapeutic compositions and methods employing such proteins and/or antibodies. DS-CAM proteins are also useful in bioassays to identify agonists and antagonists thereto.

  2. The epitope recognized by a monoclonal antibody in the myelin-associated protein CNP.

    Science.gov (United States)

    Stricker, R; Kalbacher, H; Reiser, G

    1997-08-18

    The epitope recognized by a monoclonal antibody (MAb-46-1) directed against the myelin-associated protein CNP (2',3'-cyclic nucleotide 3'-phosphodiesterase; EC 3.1.4.37) from several species was characterized. MAb-46-1 can be employed for immunoprecipitation, immunostaining in Western blots and in immunohistochemistry. Short peptides derived from the human CNP1 peptide sequence were synthesized and used in enzyme linked immunosorbent assays to test the reactivity of MAb-46-1. Coarse screening experiments enabled us to localize the epitope recognized by MAb-46-1 to the amino acid residues 9 to 19 close to the N-terminus. Further investigations using shorter peptides comprising this part of the protein allowed us to identify a 9 amino acid residue long peptide (amino acids 11 to 19: ELQFPFLQD) which represents the minimal epitope recognized by MAb-46-1, probably through a 3-dimensional structure and less likely a straight linear peptide. The epitope seems to be stabilized also by the attached amino acids 7 to 10 (KDKP). The peptide sequence 9-19 is conserved in all CNP sequences described so far. Thus, MAb-46-1 might be of general usefulness for further studies of the not yet identified function of the myelin-associated protein CNP. PMID:9268698

  3. Comprehensive mapping of common immunodominant epitopes in the eastern equine encephalitis virus E2 protein recognized by avian antibody responses.

    Directory of Open Access Journals (Sweden)

    Encheng Sun

    Full Text Available Eastern equine encephalitis virus (EEEV is a mosquito-borne virus that can cause both human and equine encephalitis with high case fatality rates. EEEV can also be widespread among birds, including pheasants, ostriches, emu, turkeys, whooping cranes and chickens. The E2 protein of EEEV and other Alphaviruses is an important immunogenic protein that elicits antibodies of diagnostic value. While many therapeutic and diagnostic applications of E2 protein-specific antibodies have been reported, the specific epitopes on E2 protein recognized by the antibody responses of different susceptible hosts, including avian species, remain poorly defined. In the present study, the avian E2-reactive polyclonal antibody (PAb response was mapped to linear peptide epitopes using PAbs elicited in chickens and ducks following immunization with recombinant EEEV E2 protein and a series of 42 partially overlapping peptides covering the entire EEEV E2 protein. We identified 12 and 13 peptides recognized by the chicken and duck PAb response, respectively. Six of these linear peptides were commonly recognized by PAbs elicited in both avian species. Among them five epitopes recognized by both avian, the epitopes located at amino acids 211-226 and 331-352 were conserved among the EEEV antigenic complex, but not other associated alphaviruses, whereas the epitopes at amino acids 11-26, 30-45 and 151-166 were specific to EEEV subtype I. The five common peptide epitopes were not recognized by avian PAbs against Avian Influenza Virus (AIV and Duck Plague Virus (DPV. The identification and characterization of EEEV E2 antibody epitopes may be aid the development of diagnostic tools and facilitate the design of epitope-based vaccines for EEEV. These results also offer information with which to study the structure of EEEV E2 protein.

  4. Iodination of monoclonal antibodies, proteins and peptide using iodogen

    International Nuclear Information System (INIS)

    The use of the iodinating reagent 1,3,4,6-tetrachloro-3α, 6α-diphenylglycholuril (Iodogen) to label monoclonal antibodies (McAbs). Proteins and peptides was invesrigated with McAbs identified as mouse IgG and IgM, arginine-vasopressin (AVP), glucagon (Glu), human insulin(hI) and albumin(Alb). The labeled products were purified by gel chromatography and their immunoreactivity were detected by RIA or IRMA> Comparison of the Iodogen method with the lactoperoxides and chloramine-T methods showed that the Iodogen method had a number of advantages: 1) technically simpler ; 2) a high labeling efficiency could be obtained; 3) the immunoreactivity of the products was minimally affected; 4) the products were stable for up to 4 months

  5. High level transient production of recombinant antibodies and antibody fusion proteins in HEK293 cells

    OpenAIRE

    Jäger, Volker; Büssow, Konrad; Wagner, Andreas; Weber, Susanne; Hust, Michael; Frenzel, André; Schirrmann, Thomas

    2013-01-01

    Background The demand of monospecific high affinity binding reagents, particularly monoclonal antibodies, has been steadily increasing over the last years. Enhanced throughput of antibody generation has been addressed by optimizing in vitro selection using phage display which moved the major bottleneck to the production and purification of recombinant antibodies in an end-user friendly format. Single chain (sc)Fv antibody fragments require additional tags for detection and are not as suitable...

  6. Pharmacokinetics of biotech drugs: peptides, proteins and monoclonal antibodies.

    Science.gov (United States)

    Lin, Jiunn H

    2009-09-01

    With the advances in recombinant DNA biotechnology, molecular biology and immunology, the number of biotech drugs, including peptides, proteins and monoclonal antibodies, available for clinical use has dramatically increased in recent years. Although pharmacokinetic principles are equally applicable to the large molecule drugs and conventional small molecule drugs, the underlying mechanisms for the processes of absorption, distribution, metabolism and excretion (ADME) of large molecule drugs are often very different from that of small molecule drugs. Therefore, a good understanding of the ADME processes of large molecule drugs is essential in support of the development of therapeutic biologics. The purpose of this article is to review the current knowledge of the ADME processes that govern the pharmacokinetics of biotech drugs. The challenges encountered by orally administered peptide and protein drugs, and the nature of lymphatic absorption after subcutaneous administration will be discussed. In addition, molecular mechanisms of biodistribution, metabolism and renal excretion of biotech drugs will also be discussed. Finally, approaches used for prediction of human pharmacokinetics of protein drugs will be briefly discussed.

  7. RNAi-based validation of antibodies for reverse phase protein arrays

    Directory of Open Access Journals (Sweden)

    Sahin Özgür

    2010-12-01

    Full Text Available Abstract Background Reverse phase protein arrays (RPPA have been demonstrated to be a useful experimental platform for quantitative protein profiling in a high-throughput format. Target protein detection relies on the readout obtained from a single detection antibody. For this reason, antibody specificity is a key factor for RPPA. RNAi allows the specific knockdown of a target protein in complex samples and was therefore examined for its utility to assess antibody performance for RPPA applications. Results To proof the feasibility of our strategy, two different anti-EGFR antibodies were compared by RPPA. Both detected the knockdown of EGFR but at a different rate. Western blot data were used to identify the most reliable antibody. The RNAi approach was also used to characterize commercial anti-STAT3 antibodies. Out of ten tested anti-STAT3 antibodies, four antibodies detected the STAT3-knockdown at 80-85%, and the most sensitive anti-STAT3 antibody was identified by comparing detection limits. Thus, the use of RNAi for RPPA antibody validation was demonstrated to be a stringent approach to identify highly specific and highly sensitive antibodies. Furthermore, the RNAi/RPPA strategy is also useful for the validation of isoform-specific antibodies as shown for the identification of AKT1/AKT2 and CCND1/CCND3-specific antibodies. Conclusions RNAi is a valuable tool for the identification of very specific and highly sensitive antibodies, and is therefore especially useful for the validation of RPPA-suitable detection antibodies. On the other hand, when a set of well-characterized RPPA-antibodies is available, large-scale RNAi experiments analyzed by RPPA might deliver useful information for network reconstruction.

  8. Intranuclear Inclusions in Renal Tubular Epithelium in Immunodeficient Mice Stain with Antibodies for Bovine Papillomavirus Type 1 L1 Protein

    Directory of Open Access Journals (Sweden)

    Elizabeth McInnes

    2015-06-01

    Full Text Available The kidneys from six immunodeficient mice examined by Cerberus Sciences and the Animal Resources Centre, displayed karyomegaly with pale eosinophilic, intranuclear inclusions upon histopathological examination. Electron microscopy performed on kidney tissue from 5/6 mice demonstrated margination of the chromatin in large nuclei. Laboratory tests were used to detect nucleic acid of papillomaviruses, polyomaviruses, circoviruses and anelloviruses (4/6 mice, a specific PCR was used to detect murine polyomavirus (1/6, and a panel of serological tests was used to detect seroconversion to major murine pathogens (1/6. All molecular and serological tests were negative. Immunohistochemistry using polyclonal anti-bovine papillomavirus type 1 (BPV-1 L1 antibody, Camvir monoclonal anti-papillomavirus antibody (directed against the seven amino acids GFGAMDF found in human papillomavirus (HPV 16 L1 protein, a commercially available mixture of two monoclonal antibodies, anti-BPV-1 L1/1H8 + Camvir antibodies, and a monoclonal anti-Hsc70 antibody revealed specific, positive staining of murine renal tubular epithelial intranuclear inclusions in 6/6 mice using the anti-BPV-1 L1 containing antibodies only. Methyl pyronin green, PAS and Feulgen histochemical reactions revealed that the intranuclear inclusions did not consist of RNA, DNA or carbohydrate. An immunohistochemical method now exists that can be used to confirm and evaluate suspected cases of murine inclusion body nephropathy.

  9. Isolation of human monoclonal antibodies to the envelope e2 protein of hepatitis C virus and their characterization.

    Directory of Open Access Journals (Sweden)

    Yohko K Shimizu

    Full Text Available We isolated and characterized two human monoclonal antibodies to the envelope E2 protein of hepatitis C virus (HCV. Lymphoblastoid cell lines stably producing antibodies were obtained by immortalizing peripheral blood mononuclear cells of a patient with chronic hepatitis C using Epstein-Barr virus. Screening for antibody-positive clones was carried out by immunofluorescence with Huh7 cells expressing the E2 protein of HCV strain H (genotype 1a isolated from the same patient. Isotype of resulting antibodies, #37 and #55, was IgG1/kappa and IgG1/lambda, respectively. Epitope mapping revealed that #37 and #55 recognize conformational epitopes spanning amino acids 429 to 652 and 508 to 607, respectively. By immunofluorescence using virus-infected Huh7.5 cells as targets both antibodies were reactive with all of the nine different HCV genotypes/subtypes tested. The antibodies showed a different pattern of immuno-staining; while #37 gave granular reactions mostly located in the periphery of the nucleus, #55 gave diffuse staining throughout the cytoplasm. Both antibodies were shown by immuno-gold electron microscopy to bind to intact viral particles. In a neutralization assay (focus-forming unit reduction using chimeric infectious HCV containing structural proteins derived from genotypes 1a, 1b, 2a, 2b, 3a, 4a, 5a, 6a, and 7a, #55 inhibited the infection of all HCV genotypes tested but genotype 7a to a lesser extent. #37 did not neutralize any of these viruses. As a broadly cross-neutralizing human antibody, #55 may be useful for passive immunotherapy of HCV infection.

  10. Specific ion and buffer effects on protein-protein interactions of a monoclonal antibody.

    Science.gov (United States)

    Roberts, D; Keeling, R; Tracka, M; van der Walle, C F; Uddin, S; Warwicker, J; Curtis, R

    2015-01-01

    Better predictive ability of salt and buffer effects on protein-protein interactions requires separating out contributions due to ionic screening, protein charge neutralization by ion binding, and salting-in(out) behavior. We have carried out a systematic study by measuring protein-protein interactions for a monoclonal antibody over an ionic strength range of 25 to 525 mM at 4 pH values (5, 6.5, 8, and 9) in solutions containing sodium chloride, calcium chloride, sodium sulfate, or sodium thiocyante. The salt ions are chosen so as to represent a range of affinities for protein charged and noncharged groups. The results are compared to effects of various buffers including acetate, citrate, phosphate, histidine, succinate, or tris. In low ionic strength solutions, anion binding affinity is reflected by the ability to reduce protein-protein repulsion, which follows the order thiocyanate > sulfate > chloride. The sulfate specific effect is screened at the same ionic strength required to screen the pH dependence of protein-protein interactions indicating sulfate binding only neutralizes protein charged groups. Thiocyanate specific effects occur over a larger ionic strength range reflecting adsorption to charged and noncharged regions of the protein. The latter leads to salting-in behavior and, at low pH, a nonmonotonic interaction profile with respect to sodium thiocyanate concentration. The effects of thiocyanate can not be rationalized in terms of only neutralizing double layer forces indicating the presence of an additional short-ranged protein-protein attraction at moderate ionic strength. Conversely, buffer specific effects can be explained through a charge neutralization mechanism, where buffers with greater valency are more effective at reducing double layer forces at low pH. Citrate binding at pH 6.5 leads to protein charge inversion and the formation of attractive electrostatic interactions. Throughout the report, we highlight similarities in the measured

  11. Specific ion and buffer effects on protein-protein interactions of a monoclonal antibody.

    Science.gov (United States)

    Roberts, D; Keeling, R; Tracka, M; van der Walle, C F; Uddin, S; Warwicker, J; Curtis, R

    2015-01-01

    Better predictive ability of salt and buffer effects on protein-protein interactions requires separating out contributions due to ionic screening, protein charge neutralization by ion binding, and salting-in(out) behavior. We have carried out a systematic study by measuring protein-protein interactions for a monoclonal antibody over an ionic strength range of 25 to 525 mM at 4 pH values (5, 6.5, 8, and 9) in solutions containing sodium chloride, calcium chloride, sodium sulfate, or sodium thiocyante. The salt ions are chosen so as to represent a range of affinities for protein charged and noncharged groups. The results are compared to effects of various buffers including acetate, citrate, phosphate, histidine, succinate, or tris. In low ionic strength solutions, anion binding affinity is reflected by the ability to reduce protein-protein repulsion, which follows the order thiocyanate > sulfate > chloride. The sulfate specific effect is screened at the same ionic strength required to screen the pH dependence of protein-protein interactions indicating sulfate binding only neutralizes protein charged groups. Thiocyanate specific effects occur over a larger ionic strength range reflecting adsorption to charged and noncharged regions of the protein. The latter leads to salting-in behavior and, at low pH, a nonmonotonic interaction profile with respect to sodium thiocyanate concentration. The effects of thiocyanate can not be rationalized in terms of only neutralizing double layer forces indicating the presence of an additional short-ranged protein-protein attraction at moderate ionic strength. Conversely, buffer specific effects can be explained through a charge neutralization mechanism, where buffers with greater valency are more effective at reducing double layer forces at low pH. Citrate binding at pH 6.5 leads to protein charge inversion and the formation of attractive electrostatic interactions. Throughout the report, we highlight similarities in the measured

  12. Analyzing swine sera for functional antibody titers against influenza A neuraminidase proteins using an enzyme-linked lectin assay (ELLA).

    Science.gov (United States)

    Sandbulte, Matthew R; Eichelberger, Maryna C

    2014-01-01

    Neuraminidase (NA) is an envelope glycoprotein of influenza viruses, including swine-lineage influenza A viruses. NA possesses sialidase activity, which is functionally important at multiple points in viral replication, counter-balancing the sialic acid receptor binding activity of the hemagglutinin (HA), the other major envelope glycoprotein. The NA proteins of influenza A viruses have been classified into nine serological subtypes, and they undergo antigenic drift variation similar to that of HA. Antibodies to NA are analyzed much less often than antibodies to HA. The conventional assay for NA inhibition (NI) antibody titration, established decades ago, is widely considered unwieldy and inefficient for routine use. In recent years, a few new formats have been developed which still measure inhibition of NA enzymatic function, but more efficiently and with less chemical waste produced. Described here is the enzyme-linked lectin assay (ELLA), which is performed in 96-well plates and analyzed on a spectrophotometric plate reader. An important factor in adoption of the ELLA technique for animal studies, such as swine, is the choice of NA antigen, which may be purified protein or whole virus containing an antigenically irrelevant HA protein. This NI assay, in conjunction with the hemagglutination inhibiting (HI) antibody assay, offers a practical way to characterize viral isolates more fully and to quantify antibodies induced by infection or vaccination.

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

    OpenAIRE

    Darragh Lemass; Richard O'Kennedy; Kijanka, Gregor S.

    2016-01-01

    Protein arrays are frequently used to profile antibody repertoires in humans and animals. High-throughput protein array characterisation of complex antibody repertoires requires a platform-dependent, lot-to-lot validation of secondary detection antibodies. This article details the validation of an affinity-isolated anti-chicken IgY antibody produced in rabbit and a goat anti-rabbit IgG antibody conjugated with alkaline phosphatase using protein arrays consisting of 7,390 distinct human protei...

  14. Novel monoclonal antibodies against Pdx1 reveal feedback regulation of Pdx1 protein levels

    Directory of Open Access Journals (Sweden)

    T. Galbo

    2010-04-01

    Full Text Available The aim of this study was to characterize two monoclonal antibodies (F6A11 and F109-D12 generated against Pdx1 (pancreatic and duodenal homeobox-1, a homeodomain transcription factor, which is critical for pancreas formation as well as for normal pancreatic beta cell function. For production of monoclonal antibodies, we immunized Robertsonian POSF (RBFmice with a GST-Pdx1 fusion protein containing a 68-amino acid C-terminal fragment of rat Pdx1. These monoclonal antibodies detect Pdx1 by western blotting and allow immunohistochemical detection of Pdx1 in both mouse and rat tissue. F6A11 and F109-D12 produce IHC staining patterns indistinguishable from that obtained with highly specific polyclonal Pdx1 antisera raised in rabbits and goats, when applied to embryonic or adult mouse pancreatic tissue. In contrast to previously generated polyclonal anti-Pdx1 antisera, we also demonstrate that F6A11 works for intracellular fluorescence activated cell sorting (FACS staining of Pdx1. By using F6A11, we characterize the induction of Pdx1 in the Doxycycline (DOX inducible insulinoma cell line INSrαβ-Pdx1 and follow the reduction of Pdx1 after removing Dox. Finally, we show that induction of exogenous Pdx1 leads to a reduction in endogenous Pdx1 levels, which suggests that a negative feedback loop is involved in maintaining correct levels of Pdx1 in the cell.

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

    Directory of Open Access Journals (Sweden)

    Nazila Amini

    2014-06-01

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

  16. Isolation of Camelid Single-Domain Antibodies Against Native Proteins Using Recombinant Multivalent Peptide Ligands.

    Science.gov (United States)

    Alturki, Norah A; Henry, Kevin A; MacKenzie, C Roger; Arbabi-Ghahroudi, Mehdi

    2015-01-01

    Generation of antibodies against desired epitopes on folded proteins may be hampered by various characteristics of the target protein, including antigenic and immunogenic dominance of irrelevant epitopes and/or steric occlusion of the desired epitope. In such cases, peptides encompassing linear epitopes of the native protein represent attractive alternative reagents for immunization and screening. Peptide antigens are typically prepared by fusing or conjugating the peptide of interest to a carrier protein. The utility of such antigens depends on many factors including the peptide's amino acid sequence, display valency, display format (synthetic conjugate vs. recombinant fusion) and characteristics of the carrier. Here we provide detailed protocols for: (1) preparation of DNA constructs encoding peptides fused to verotoxin (VT) multimerization domain; (2) expression, purification, and characterization of the multivalent peptide-VT ligands; (3) concurrent panning of a non-immune phage-displayed camelid VHH library against the peptide-VT ligands and native protein; and (4) identification of VHHs enriched via panning using next-generation sequencing techniques. These methods are simple, rapid and can be easily adapted to yield custom peptide-VT ligands that appear to maintain the antigenic structures of the peptide. However, we caution that peptide sequences should be chosen with great care, taking into account structural, immunological, and biophysical information on the protein of interest.

  17. Surface plasmon resonance-enhanced fluorescence implementation of a single-step competition assay: demonstration of fatty acid measurement using an anti-fatty acid monoclonal antibody and a Cy5-labeled fatty acid.

    Science.gov (United States)

    Vareiro, Margarida M L M; Tranchant, Isabelle; Maplin, Sandra; Zak, Kris; Gani, M M; Slevin, Christopher J; Hailes, Helen C; Tabor, Alethea B; Cameron, Petra J; Jenkins, A Toby A; Williams, David E

    2008-06-15

    The development of a single-step, separation-free method for measurement of low concentrations of fatty acid using a surface plasmon resonance-enhanced fluorescence competition assay with a surface-bound antibody is described. The assay behavior was unexpectedly complex. A nonlinear coverage-dependent self-quenching of emission from surface-bound fluorescent label was deduced from the response kinetics and attributed to a surface plasmon-mediated energy transfer between adsorbed fluorophores, modified by the effects of plasmon interference. Principles of assay design to avoid complications from such effects are discussed. An anti-fatty acid mouse monoclonal antibody reacting to the alkyl chain was prepared and supported on a gold chip at a spacing appropriate for surface-plasmon field-enhanced fluorescence spectroscopy (SPEFS), by applying successively a self-assembled biotinylated monolayer, then streptavidin, then biotinylated protein A, and then the antibody, which was crosslinked to the protein A. Synthesis of a fluorescently (Cy5) tagged C-11 fatty acid is reported. SPEFS was used to follow the kinetics of the binding of the labeled fatty acid to the antibody, and to implement a competition assay with free fatty acid (undecanoic acid), sensitive at the 1 microM scale, a sensitivity limit caused by the low affinity of antibodies for free fatty acids, rather than the SPEFS technique itself. Free fatty acid concentration in human serum is in the range 0.1-1mM, suggesting that this measurement approach could be applied in a clinical diagnostic context. Finally, a predictive, theoretical model of fatty acid binding was developed that accounted for the observed "overshoot" kinetics.

  18. Characterization of monoclonal antibodies to a crystal protein of Bacillus thuringiensis subsp. kurstaki.

    OpenAIRE

    Huber-Lukac, M; Jaquet, F; Luethy, P; Huetter, R; Braun, D G

    1986-01-01

    Ten monoclonal antibodies were produced against a k-1-type crystal protein of Bacillus thuringiensis subsp. kurstaki. Eight of the antibodies belong to the immunoglobulin G1 (IgG1) subclass, with pI values ranging from 5.5 to 8.6, one could be assigned to the IgG2b subclass, and one could be assigned to the IgM class. Competitive antibody-binding assays and analysis of antibody specificity indicated that the 10 antibodies recognized at least nine distinct antigenic determinants. Eight antibod...

  19. Characterization of antibodies directed against the Ankrd2 human muscle protein

    OpenAIRE

    Kojić Snežana; Medeot Elisa; Faulkner Georgine

    2009-01-01

    In order to study the function of the Ankrd2 protein, for which commercial antibodies are not available, we report the production and analysis of polyclonal antibodies to full-length Ankrd2 and its C-terminal and N-terminal regions, as well as a monoclonal antibody to the C-terminus of the protein. Epitope mapping making use of recombinant deletion mutants showed that an epitope located in region 323-333 aa of Ankrd2 is detected by the monoclonal antibody. The high specificity of all four ant...

  20. Investigating interactions between phospholipase B-Like 2 and antibodies during Protein A chromatography.

    Science.gov (United States)

    Tran, Benjamin; Grosskopf, Vanessa; Wang, Xiangdan; Yang, Jihong; Walker, Don; Yu, Christopher; McDonald, Paul

    2016-03-18

    Purification processes for therapeutic antibodies typically exploit multiple and orthogonal chromatography steps in order to remove impurities, such as host-cell proteins. While the majority of host-cell proteins are cleared through purification processes, individual host-cell proteins such as Phospholipase B-like 2 (PLBL2) are more challenging to remove and can persist into the final purification pool even after multiple chromatography steps. With packed-bed chromatography runs using host-cell protein ELISAs and mass spectrometry analysis, we demonstrated that different therapeutic antibodies interact to varying degrees with host-cell proteins in general, and PLBL2 specifically. We then used a high-throughput Protein A chromatography method to further examine the interaction between our antibodies and PLBL2. Our results showed that the co-elution of PLBL2 during Protein A chromatography is highly dependent on the individual antibody and PLBL2 concentration in the chromatographic load. Process parameters such as antibody resin load density and pre-elution wash conditions also influence the levels of PLBL2 in the Protein A eluate. Furthermore, using surface plasmon resonance, we demonstrated that there is a preference for PLBL2 to interact with IgG4 subclass antibodies compared to IgG1 antibodies. PMID:26896920

  1. Antibody recognition of porcine circovirus type 2 capsid protein epitopes after vaccination, infection, and disease.

    Science.gov (United States)

    Trible, Benjamin R; Kerrigan, Maureen; Crossland, Nicholas; Potter, Megan; Faaberg, Kay; Hesse, Richard; Rowland, Raymond R R

    2011-05-01

    Open reading frame 2 (ORF2) of porcine circovirus type 2 (PCV2) codes for the 233-amino-acid capsid protein (CP). Baculovirus-based vaccines that express only ORF2 are protective against clinical disease following experimental challenge or natural infection. The goal of this study was to identify regions in CP preferentially recognized by sera from experimentally infected and vaccinated pigs and to compare these responses to those of pigs diagnosed with porcine circovirus-associated disease (PCVAD), including porcine multisystemic wasting syndrome (PMWS) and porcine dermatitis and nephropathy syndrome (PDNS). The approach was to react porcine sera with CP polypeptide fragments followed by finer mapping studies using overlapping oligopeptides that covered amino acids 141 to 200. The results showed that vaccinated pigs preferentially recognized only the largest polypeptide fragment, CP(43-233). A subset of experimentally infected pigs and pigs with PDNS showed strong reactivity against a CP oligopeptide, 169-STIDYFQPNNKR-180. Alanine scanning identified Y-173, F-174, Q-175, and K-179 as important for antibody recognition. The results from this study support the notion of PCV2 modulation of immunity, including antibody responses that may represent a precursor for disease. The recognition of CP(169-180) and other polypeptides provides opportunities to devise diagnostic tests for monitoring the immunological effectiveness of vaccination. PMID:21430122

  2. Inhibition of Staphylococcus epidermidis biofilm formation by rabbit polyclonal antibodies against the SesC protein.

    NARCIS (Netherlands)

    Shahrooei, M.; Hira, V.; Stijlemans, B.; Merckx, R.; Hermans, P.W.M.; Eldere, J. van

    2009-01-01

    Several well-studied proteins with defined roles in Staphylococcus epidermidis biofilm formation are LPXTG motif-containing proteins. Here, we investigate the possible use of the LPXTG motif-containing protein SesC (S. epidermidis surface protein C; accession no. NP_765787) as a target for antibodie

  3. P53 FUSION PROTEIN EXPRESSION IN PROKARYOTE AND PREPARATION OF MONOCLONAL ANTIBODY TO P53

    Institute of Scientific and Technical Information of China (English)

    Liu Caiyun; Shou Chengchao; Sun Sulian; ZhangLei; Zeng Li

    1998-01-01

    Objective: Conventional immunohistochemistry (IHC) is available to assess P53 mutations, and expensive imported anti-P53 monoclonal antibody has been used in China, it is necessary to study a new monoclonal antibody.Methods: The P53 DNA fragment enconding N-terminal 180 amiao acide was obtained by PCR and was cloned into PGEX-2T plasmid expressing glutathione S-transferase (GST). The P53-GST fusion protein expressed by JM109was used for immunizing BALB/C mice. We have raised one hybridoma strain secreting McAb to human P53(named M126). Results: The IHC analysis of 52paraffin-embedded sections from human breast cancer with M126 and PAB1801 (Zymed Co.) has showed that the positive immunoreactions were 25 cases (48%) and 22cases (42.3%) respectively. The staining of M126 was stronger and preferable to PAB1801. Conclusion: M126can be instead of PAB1801 for studying immunohistochemical analysis on P53 Protein.

  4. Reactivity of Antibodies from Syphilis Patients to a Protein Array Representing the Treponema pallidum Proteome†

    OpenAIRE

    Brinkman, Mary Beth; McKevitt, Matthew; McLoughlin, Melanie; Perez, Carla; Howell, Jerrilyn; Weinstock, George M.; Norris, Steven J; Palzkill, Timothy

    2006-01-01

    To identify antigens important in the human immune response to syphilis, the serum antibody reactivity of syphilitic patients was examined with 908 of the 1,039 proteins in the proteome of Treponema pallidum subsp. pallidum using a protein array enzyme-linked immunosorbent assay. Thirty-four proteins exhibited significant reactivity when assayed with human sera from patients in the early latent stage of syphilis. A subset of antigens identified were further scrutinized for antibody reactivity...

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

    OpenAIRE

    Nazila Amini; Mohadeseh Naghi Vishteh; Omid Zarei; Reza Hadavi; Negah Ahmadvand; Hodjattallah Rabbani; Mahmood Jeddi-Tehrani

    2014-01-01

    Objective(s):Antibodies against actin, as one of the most widely studied structural and multifunctional housekeeping proteins in eukaryotic cells, are used as internal loading controls in western blot analyses. The aim of this study was to produce polyclonal antibody against a synthetic peptide derived from N-terminal region of β-actin protein to be used as a protein loading control in western blot and other assay systems. Materials and Methods: A synthetic peptide derived from β-actin protei...

  6. Macromolecular mimicry of nucleic acid and protein

    DEFF Research Database (Denmark)

    Nautrup Pedersen, Gitte; Nyborg, Jens; Clark, Brian F

    1999-01-01

    of the concept of macromolecular mimicry. Macromolecular mimicry has further been proposed among initiation and release factors, thereby adding a new element to the description of protein synthesis in bacteria. Such mimicry has also been observed in other biological processes such as autoimmunity, DNA repair......Although proteins and nucleic acids consist of different chemical components, proteins can mimic structures and possibly also functions of nucleic acids. Recently, structural mimicry was observed between two elongation factors in bacterial protein biosynthesis leading to the introduction...

  7. Rational design of antibodies targeting specific epitopes within intrinsically disordered proteins

    Science.gov (United States)

    Sormanni, Pietro; Aprile, Francesco A.; Vendruscolo, Michele

    2015-01-01

    Antibodies are powerful tools in life sciences research, as well as in diagnostic and therapeutic applications, because of their ability to bind given molecules with high affinity and specificity. Using current methods, however, it is laborious and sometimes difficult to generate antibodies to target specific epitopes within a protein, in particular if these epitopes are not effective antigens. Here we present a method to rationally design antibodies to enable them to bind virtually any chosen disordered epitope in a protein. The procedure consists in the sequence-based design of one or more complementary peptides targeting a selected disordered epitope and the subsequent grafting of such peptides on an antibody scaffold. We illustrate the method by designing six single-domain antibodies to bind different epitopes within three disease-related intrinsically disordered proteins and peptides (α-synuclein, Aβ42, and IAPP). Our results show that all these designed antibodies bind their targets with good affinity and specificity. As an example of an application, we show that one of these antibodies inhibits the aggregation of α-synuclein at substoichiometric concentrations and that binding occurs at the selected epitope. Taken together, these results indicate that the design strategy that we propose makes it possible to obtain antibodies targeting given epitopes in disordered proteins or protein regions. PMID:26216991

  8. Rational design of antibodies targeting specific epitopes within intrinsically disordered proteins.

    Science.gov (United States)

    Sormanni, Pietro; Aprile, Francesco A; Vendruscolo, Michele

    2015-08-11

    Antibodies are powerful tools in life sciences research, as well as in diagnostic and therapeutic applications, because of their ability to bind given molecules with high affinity and specificity. Using current methods, however, it is laborious and sometimes difficult to generate antibodies to target specific epitopes within a protein, in particular if these epitopes are not effective antigens. Here we present a method to rationally design antibodies to enable them to bind virtually any chosen disordered epitope in a protein. The procedure consists in the sequence-based design of one or more complementary peptides targeting a selected disordered epitope and the subsequent grafting of such peptides on an antibody scaffold. We illustrate the method by designing six single-domain antibodies to bind different epitopes within three disease-related intrinsically disordered proteins and peptides (α-synuclein, Aβ42, and IAPP). Our results show that all these designed antibodies bind their targets with good affinity and specificity. As an example of an application, we show that one of these antibodies inhibits the aggregation of α-synuclein at substoichiometric concentrations and that binding occurs at the selected epitope. Taken together, these results indicate that the design strategy that we propose makes it possible to obtain antibodies targeting given epitopes in disordered proteins or protein regions.

  9. Synthetic oligonucleotide antigens modified with locked nucleic acids detect disease specific antibodies

    Science.gov (United States)

    Samuelsen, Simone V.; Solov’yov, Ilia A.; Balboni, Imelda M.; Mellins, Elizabeth; Nielsen, Christoffer Tandrup; Heegaard, Niels H. H.; Astakhova, Kira

    2016-01-01

    New techniques to detect and quantify antibodies to nucleic acids would provide a significant advance over current methods, which often lack specificity. We investigate the potential of novel antigens containing locked nucleic acids (LNAs) as targets for antibodies. Particularly, employing molecular dynamics we predict optimal nucleotide composition for targeting DNA-binding antibodies. As a proof of concept, we address a problem of detecting anti-DNA antibodies that are characteristic of systemic lupus erythematosus, a chronic autoimmune disease with multiple manifestations. We test the best oligonucleotide binders in surface plasmon resonance studies to analyze binding and kinetic aspects of interactions between antigens and target DNA. These DNA and LNA/DNA sequences showed improved binding in enzyme-linked immunosorbent assay using human samples of pediatric lupus patients. Our results suggest that the novel method is a promising tool to create antigens for research and point-of-care monitoring of anti-DNA antibodies. PMID:27775006

  10. Protein and ligand adaptation in a retinoic acid binding protein.

    OpenAIRE

    Pattanayek, R.; Newcomer, M E

    1999-01-01

    A retinoic acid binding protein isolated from the lumen of the rat epididymis (ERABP) is a member of the lipocalin superfamily. ERABP binds both the all-trans and 9-cis isomers of retinoic acid, as well as the synthetic retinoid (E)-4-[2-(5,6,7,8)-tetrahydro-5,5,8,8-tetramethyl-2 napthalenyl-1 propenyl]-benzoic acid (TTNPB), a structural analog of all-trans retinoic acid. The structure of ERABP with a mixture of all-trans and 9-cis retinoic acid has previously been reported. To elucidate any ...

  11. Detection of IgG antibodies against Bordetella pertussis with /sup 125/I-protein A

    Energy Technology Data Exchange (ETDEWEB)

    Wirsing von Koenig, C.H.; Finger, H.

    1981-01-01

    A method for the detection of IgG antibodies against Bordetella pertussis is described, based on the principle of 'sandwich' radioimmunoassay. /sup 125/I protein A is used as radioactive tracer. The influence of amounts of antigen, antibody, radioactive tracer, incubation time and temperature were tested and the optimal conditions for the assay are described. The procedure offers a simple, quick, and sensitive method for detecting antibodies against B. pertussis. Application and limitation of the test are discussed.

  12. Production of Borreliacidal Antibody to Outer Surface Protein A In Vitro and Modulation by Interleukin-4

    OpenAIRE

    Munson, Erik L.; Du Chateau, Brian K.; Jobe, Dean A.; Lovrich, Steven D.; Callister, Steven M.; Schell, Ronald F.

    2000-01-01

    Borreliacidal antibody production is one of several parameters for establishing the effectiveness of Borrelia burgdorferi vaccines. The production of borreliacidal antibody was studied in vitro by culturing immune lymph node cells with macrophages and B. burgdorferi. We showed that borreliacidal antibody, directed primarily against outer surface protein A (OspA), was readily produced by lymph node cells obtained from C3H/HeJ mice vaccinated with formalin-inactivated B. burgdorferi in aluminum...

  13. Soya protein antibodies in man: their occurrence and possible relevance in coeliac disease.

    OpenAIRE

    Haeney, M. R.; Goodwin, B. J.; Barratt, M E; Mike, N.; Asquith, P.

    1982-01-01

    Circulating antibodies to soya-derived protein antigens have been measured in patients with duodenitis, Crohn's disease, ulcerative colitis and coeliac disease. Significantly raised antibody titres were found frequently in the coeliac group, particularly those patients showing a suboptimal response to a gluten-free diet, but rarely in subjects with other gastrointestinal diseases. Antisoya activity was not necessarily accompanied by antibodies to other common dietary antigens. We suggest that...

  14. Mapping Epitopes on a Protein Antigen by the Proteolysis of Antigen-Antibody Complexes

    Science.gov (United States)

    Jemmerson, Ronald; Paterson, Yvonne

    1986-05-01

    A monoclonal antibody bound to a protein antigen decreases the rate of proteolytic cleavage of the antigen, having the greatest effect on those regions involved in antibody contact. Thus, an epitope can be identified by the ability of the antibody to protect one region of the antigen more than others from proteolysis. By means of this approach, two distinct epitopes, both conformationally well-ordered, were characterized on horse cytochrome c.

  15. Lepromatous leprosy patients produce antibodies that recognise non-bilayer lipid arrangements containing mycolic acids

    Directory of Open Access Journals (Sweden)

    Isabel Baeza

    2012-12-01

    Full Text Available Non-bilayer phospholipid arrangements are three-dimensional structures that form when anionic phospholipids with an intermediate structure of the tubular hexagonal phase II are present in a bilayer of lipids. Antibodies that recognise these arrangements have been described in patients with antiphospholipid syndrome and/or systemic lupus erythematosus and in those with preeclampsia; these antibodies have also been documented in an experimental murine model of lupus, in which they are associated with immunopathology. Here, we demonstrate the presence of antibodies against non-bilayer phospholipid arrangements containing mycolic acids in the sera of lepromatous leprosy (LL patients, but not those of healthy volunteers. The presence of antibodies that recognise these non-bilayer lipid arrangements may contribute to the hypergammaglobulinaemia observed in LL patients. We also found IgM and IgG anti-cardiolipin antibodies in 77% of the patients. This positive correlation between the anti-mycolic-non-bilayer arrangements and anti-cardiolipin antibodies suggests that both types of antibodies are produced by a common mechanism, as was demonstrated in the experimental murine model of lupus, in which there was a correlation between the anti-non-bilayer phospholipid arrangements and anti-cardiolipin antibodies. Antibodies to non-bilayer lipid arrangements may represent a previously unrecognised pathogenic mechanism in LL and the detection of these antibodies may be a tool for the early diagnosis of LL patients.

  16. Species-specific antibody responses to the recombinant 53-kilodalton excretory and secretory proteins in mice infected with Trichinella spp.

    Science.gov (United States)

    Nagano, Isao; Wu, Zhiliang; Takahashi, Yuzo

    2008-03-01

    The 53-kDa proteins in larval excretory and secretory (E-S) products were expressed from five Trichinella species (T. spiralis, T. britovi, T. nativa, T. pseudospiralis, and T. papuae), using the Escherichia coli expression system, and the antibody responses to the 53-kDa recombinant proteins in mice infected with Trichinella spp. were analyzed by Western blotting. The 53-kDa protein is conserved among the five Trichinella species, with >60% similarity in amino acid sequences. The 53-kDa recombinant proteins of T. spiralis and T. pseudospiralis reacted to sera from mice infected with T. spiralis and T. pseudospiralis at 8 days postinfection (p.i.), respectively. An antibody against the 53-kDa recombinant protein of T. spiralis recognized the 53-kDa protein in the crude extracts from adult worms and 30-day p.i. muscle larvae and E-S products from muscle larvae of T. spiralis but did not recognize any proteins from T. pseudospiralis. The sera from the mice infected with T. spiralis strongly reacted with the 53-kDa recombinant protein of T. spiralis but did not react with the 53-kDa recombinant proteins of T. britovi, T. nativa, T. pseudospiralis, and T. papuae. Similarly, the sera from mice infected with T. britovi, T. nativa, T. pseudospiralis, or T. papuae strongly reacted with the 53-kDa recombinant proteins of T. britovi, T. nativa, T. pseudospiralis, or T. papuae, respectively. These results showed that the 53-kDa recombinant proteins provide early and species-specific antibody responses in mice infected with Trichinella spp. PMID:18184826

  17. 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.

  18. Liver Fatty Acid Binding Protein and Obesity

    OpenAIRE

    Atshaves, B.P.; Martin, G G; Hostetler, H.A.; McIntosh, A.L.; Kier, A B; Schroeder, F.

    2010-01-01

    While low levels of unesterified long chain fatty acids (LCFAs) are normal metabolic intermediates of dietary and endogenous fat, LCFAs are also potent regulators of key receptors/enzymes, and at high levels become toxic detergents within the cell. Elevated levels of LCFAs are associated with diabetes, obesity, and metabolic syndrome. Consequently, mammals evolved fatty acid binding proteins (FABPs) that bind/sequester these potentially toxic free fatty acids in the cytosol and present them f...

  19. Detection of major capsid protein of infectious myonecrosis virus in shrimps using monoclonal antibodies.

    Science.gov (United States)

    Seibert, Caroline H; Borsa, Mariana; Rosa, Rafael D; Cargnin-Ferreira, Eduardo; Pereira, Alitiene M L; Grisard, Edmundo C; Zanetti, Carlos R; Pinto, Aguinaldo R

    2010-10-01

    Infectious myonecrosis virus (IMNV) has been causing a progressive disease in farm-reared shrimps in Brazil and Indonesia. Immunodiagnostic methods for IMNV detection, although reliable, are not employed currently because monoclonal antibodies (MAbs) against this virus are not available. In this study, a fragment of the IMNV major capsid protein gene, comprising amino acids 300-527 (IMNV(300-527)), was cloned and expressed in Escherichia coli. The nucleotide sequence of the recombinant IMNV(300-527) fragment displayed a high degree of identity to the major capsid protein of IMNV isolates from Brazil (99%) and Indonesia (98%). Ten MAbs were generated against the expressed fragment, and eight of these, mostly IgG(2a) or IgG(2b), were able to bind to IMNV in tissue extracts from shrimps infected naturally in immunodot-blot assays. Six of these MAbs recognized a approximately 100 kDa protein in a Western-blot, which is the predicted mass of IMNV major capsid protein, and also bound to viral inclusions present in muscle fibroses and in coagulative myonecrosis, as demonstrated by immunohistochemistry. Among all those MAbs created, four did not cross-react with non-infected shrimp tissues; this observation supports their applicability as a sensitive and specific immunodiagnosis of IMNV infection in shrimps.

  20. Radiometric immunosorbent assay for the detection of anti-hormone-binding protein antibodies

    International Nuclear Information System (INIS)

    A radiometric immunosorbent assay (RISA) for the detection of monoclonal antibodies to hormone-binding proteins has been developed. The assay involves incubating hybridoma supernatants in microtiter wells that have been coated with goat anti-mouse IgG antibodies. Any mouse IgG in the test supernatant is thus specifically retained in the wells. Radioactive ligand-binding protein complexes are then incubated in the wells. The presence of anti-binding protein antibodies in the supernatant is indicated by specific retention of radioactive ligand-binding protein complexes in the wells. Crude antigen preparations, such as tissue homogenates, can be used to detect antibodies. The assay is capable of detecting antibody at concentrations 20 ng/ml (approx. 100 pM IgG). The RISA has been used successfully to screen for monoclonal antibodies to the intracellular receptor for 1,25-dihydroxyvitamin D3 and should be useful for the detection of antibodies to ligand-binding proteins in general

  1. Radiometric immunosorbent assay for the detection of anti-hormone-binding protein antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, E.A.; Dame, M.C.; DeLuca, H.F.

    1986-02-15

    A radiometric immunosorbent assay (RISA) for the detection of monoclonal antibodies to hormone-binding proteins has been developed. The assay involves incubating hybridoma supernatants in microtiter wells that have been coated with goat anti-mouse IgG antibodies. Any mouse IgG in the test supernatant is thus specifically retained in the wells. Radioactive ligand-binding protein complexes are then incubated in the wells. The presence of anti-binding protein antibodies in the supernatant is indicated by specific retention of radioactive ligand-binding protein complexes in the wells. Crude antigen preparations, such as tissue homogenates, can be used to detect antibodies. The assay is capable of detecting antibody at concentrations 20 ng/ml (approx. 100 pM IgG). The RISA has been used successfully to screen for monoclonal antibodies to the intracellular receptor for 1,25-dihydroxyvitamin D/sub 3/ and should be useful for the detection of antibodies to ligand-binding proteins in general.

  2. Antiphospholipid Antibody and Antiphospholipid Syndrome

    Institute of Scientific and Technical Information of China (English)

    吴竞生

    2008-01-01

    @@ Antiphospholipid antibodies (APA) APA is a big category for all kinds of negative charge phospholipid or lecithin - a protein complex autoantibodies or the same antibody, through its recognition of antigen (target protein) different, and phospholipids or lecithin - protein complex combination of various rely on the interference Phospholipid clotting and anti-coagulation factor, and promote endothelial cells, platelets, complement activation and play a role. APA including lupus anticoagulant(LA) and anticardiolipin antibody (ACA), In addition, there are anti-β2 glycoprotein-I (β2-GPI) antibody, anti-prothrombin (a- PT) antibody, anti-lysophosphatidic acid antibody and anti-phosphatidylserine antibody, and so on. APA as the main target of phospholipid-binding protein, including β2-GPI, prothrombin, annexin, protein C (PC) and protein S (PS), plasminogen, and so on.

  3. Production and Characterization of Monoclonal Antibodies of Shrimp White Spot Syndrome Virus Envelope Protein VP28

    Institute of Scientific and Technical Information of China (English)

    Wan-gang GU; Jun-fa YUAN; Ge-lin XU; Li-juan LI; Ni LIU; Cong ZHANG; Jian-hong ZHANG; Zheng-li SHI

    2007-01-01

    BALB/c mice were immunized with purified White spot syndrome virus (WSSV).Six monoclonal antibody cell lines were selected by ELISA with VP28 protein expressed in E.coll in vitro neutralization experiments showed that 4 of them could inhibit the virus infection in crayfish.Westernblot suggested that all these monoclonal antibodies were against the conformational structure of VP28.The monoclonal antibody 7B4 was labeled with colloidal gold particles and used to locate the VP28 on virus envelope by immunogold labeling.These monoclonal antibodies could be used to develop immunological diagnosis methods for WSSV infection.

  4. DEMONSTRATION OF MULTIPLE ANTIGENIC DETERMINANTS ON 'MYCOPLASMA PNEUMONIAE' ATTACHMENT PROTEIN BY MONOCLONAL ANTIBODIES

    Science.gov (United States)

    Distinct multiple antigenic determinants of the attachment protein of Mycoplasma pneumoniae have been identified by limited proteolytic cleavage using specific monoclonal antibodies. Western blots prepared from the gels containing the cleaved fragments were probed with antiserum ...

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

    Directory of Open Access Journals (Sweden)

    Yan-Ping Tian

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

  6. The effects of acylation stimulating protein supplementation VS antibody neutralization on energy expenditure in wildtype mice

    Directory of Open Access Journals (Sweden)

    Gao Ying

    2010-04-01

    Full Text Available Abstract Background Acylation stimulating protein (ASP is an adipogenic hormone that stimulates triglyceride (TG synthesis and glucose transport in adipocytes. Previous studies have shown that ASP-deficient C3 knockout mice are hyperphagic yet lean, as they display increased oxygen consumption and fatty acid oxidation compared to wildtype mice. In the present study, antibodies against ASP (Anti-ASP and human recombinant ASP (rASP were tested in vitro and in vivo. Continuous administration for 4 weeks via osmotic mini-pump of Anti-ASP or rASP was evaluated in wildtype mice on a high-fat diet (HFD to examine their effects on body weight, food intake and energy expenditure. Results In mature murine adipocytes, rASP significantly stimulated fatty acid uptake (+243% vs PBS, P Conclusion In vitro, Anti-ASP effectively neutralized ASP stimulated fatty acid uptake. In vivo, Anti-ASP treatment increased whole body energy utilization while rASP increased energy storage. Therefore, ASP is a potent anabolic hormone that may also be a mediator of energy expenditure.

  7. A commercial human protamine-2 antibody used in several studies to detect mouse protamine-2 recognizes mouse transition protein-2 but not protamine-2.

    Science.gov (United States)

    Eckhardt, Matthias; Wang-Eckhardt, Lihua

    2015-11-01

    The exchange of histones for transition proteins (TNPs) and finally protamines is an essential process during spermatogenesis that enables the strong condensation of chromatin during sperm formation. Research on this process obviously depends on the availability of specific antibodies recognizing these nuclear proteins. A commercial antibody generated against human protamine-2 (PRM2) has been described to cross-react with mouse PRM2 and in fact has been used in several studies to detect mouse PRM2. Some inconsistent results obtained with this goat-derived antibody prompted us to re-examine its specificity. In immunofluorescence experiments with epididymal sperm, only a low percentage of sperm nuclei were stained by this antibody, whereas a mouse monoclonal anti- PRM2 antibody stained most sperm, as expected. Western blot analysis of basic nuclear proteins from spermatids and sperm separated by acid urea (AU) gel electrophoresis revealed that the goat anti- PRM2 antiserum binds to mouse TNP2 but not mouse PRM2. Epitope mapping using glutathione-S-transferase-fusion proteins with peptide sequences conserved in human PRM2 and mouse TNP2 identified the tetrapeptide arginyl-lysyl-arginyl-threonine as an epitope of the goat anti- PRM2 antiserum. Our findings underline the importance of using AU gel electrophoresis to confirm specificities of antibodies directed against basic nuclear proteins, which are not well separated, and may show abnormal migration behaviour, in SDS-polyacrylamide gel electrophoresis. PMID:26268249

  8. Design of cyclic peptides that bind protein surfaces with antibody-like affinity.

    Science.gov (United States)

    Millward, Steven W; Fiacco, Stephen; Austin, Ryan J; Roberts, Richard W

    2007-09-21

    There is a pressing need for new molecular tools to target protein surfaces with high affinity and specificity. Here, we describe cyclic messenger RNA display with a trillion-member covalent peptide macrocycle library. Using this library, we have designed a number of high-affinity, redox-insensitive, cyclic peptides that target the signaling protein G alpha i1. In addition to cyclization, our library construction took advantage of an expanded genetic code, utilizing nonsense suppression to insert N-methylphenylalanine as a 21st amino acid. The designed macrocycles exhibit several intriguing features. First, the core motif seen in all of the selected variants is the same and shares an identical context with respect to the macrocyclic scaffold, consistent with the idea that selection simultaneously optimizes both the cyclization chemistry and the structural placement of the binding epitope. Second, detailed characterization of one molecule, cyclic G alpha i binding peptide (cycGiBP), demonstrates substantially enhanced proteolytic stability relative to that of the parent linear molecule. Third and perhaps most important, the cycGiBP peptide binds the target with very high affinity ( K i approximately 2.1 nM), similar to those of many of the best monoclonal antibodies and higher than that of the betagamma heterodimer, an endogenous G alpha i1 ligand. Overall the work provides a general route to design novel, low-molecular-weight, high-affinity ligands that target protein surfaces.

  9. Generation of a panel of antibodies against proteins encoded on human chromosome 21

    Directory of Open Access Journals (Sweden)

    Wiseman Frances K

    2010-08-01

    Full Text Available Abstract Background Down syndrome (DS is caused by trisomy of all or part of chromosome 21. To further understanding of DS we are working with a mouse model, the Tc1 mouse, which carries most of human chromosome 21 in addition to the normal mouse chromosome complement. This mouse is a model for human DS and recapitulates many of the features of the human syndrome such as specific heart defects, and cerebellar neuronal loss. The Tc1 mouse is mosaic for the human chromosome such that not all cells in the model carry it. Thus to help our investigations we aimed to develop a method to identify cells that carry human chromosome 21 in the Tc1 mouse. To this end, we have generated a panel of antibodies raised against proteins encoded by genes on human chromosome 21 that are known to be expressed in the adult brain of Tc1 mice Results We attempted to generate human specific antibodies against proteins encoded by human chromosome 21. We selected proteins that are expressed in the adult brain of Tc1 mice and contain regions of moderate/low homology with the mouse ortholog. We produced antibodies to seven human chromosome 21 encoded proteins. Of these, we successfully generated three antibodies that preferentially recognise human compared with mouse SOD1 and RRP1 proteins on western blots. However, these antibodies did not specifically label cells which carry a freely segregating copy of Hsa21 in the brains of our Tc1 mouse model of DS. Conclusions Although we have successfully isolated new antibodies to SOD1 and RRP1 for use on western blots, in our hands these antibodies have not been successfully used for immunohistochemistry studies. These antibodies are freely available to other researchers. Our data high-light the technical difficulty of producing species-specific antibodies for both western blotting and immunohistochemistry.

  10. Immune response in mice to ingested soya protein: antibody production, oral tolerance and maternal transfer

    DEFF Research Database (Denmark)

    Christensen, Hanne Risager; Pedersen, Susanne Brix; Frøkiær, Hanne

    2004-01-01

    While allergic reactions to soya are increasingly investigated, the normal immune response to ingested soya is scarcely described. In the present study, we wanted to characterise the soya-specific immune response in healthy mice ingesting soya protein. Mice fed a soya-containing diet (F0) and mice...... of the first (F1) and second (F2) offspring generation bred on a soya protein-free diet were used either directly or were transferred between the soya-containing and soya protein-free diet during pregnancy or neonatal life. The mice were compared as to levels of naturally occurring specific antibodies analysed...... by ELISA, and to the presence of oral tolerance detected as a suppressed antibody and cell-proliferation response upon immunisation with soya protein. F0 mice generated soya-specific antibodies, while oral tolerance to the same soya proteins was also clearly induced. When F0 dams were transferred to soya...

  11. Detection of non-protein amino acids in the presence of protein amino acids. II.

    Science.gov (United States)

    Shapshak, P.; Okaji, M.

    1972-01-01

    Studies conducted with the JEOL 5AH amino acid analyzer are described. This instrument makes possible the programming of the chromatographic process. Data are presented showing the separations of seventeen non-protein amino acids in the presence of eighteen protein amino acids. It is pointed out that distinct separations could be obtained in the case of a number of chemically similar compounds, such as ornithine and lysine, N-amidino alanine and arginine, and iminodiacetic acid and S-carboxymethyl cysteine and aspartic acid.

  12. Production of the Polyclonal Anti-human Metallothionein 2A Antibody with Recombinant Protein Technology

    Institute of Scientific and Technical Information of China (English)

    Faiz M.M.T.MARIKAR; Qi-Ming SUN; Zi-Chun HUA

    2006-01-01

    Metallothionein 2A (MT2A) is a small stress response protein that can be induced by exposure to toxic metals. It is highly expressed in breast cancer cells. In this study, the eDNA encoding the human MT2A protein was expressed as glutathione S-transferase (GST) fusion protein in Escherichia coli.Recombinant MT2A proteins were loaded onto 12% sodium dodecylsulfate-polyacrylamide gel and separated by electrophoresis, the recombinant protein was visualized by Coomassie blue staining and the 33 kDa recombinant GST-MT2A fusion protein band was cut out from the gel. The gel slice was minced and used to generate polyclonal antisera. Immunization of rabbit against MT2A protein allowed the production of high titer polyclonal antiserum. This new polyclonal antibody recognized recombinant MT2A protein in Western blot analysis. This low-cost antibody will be useful for detection in various immuno-assays.

  13. Antibodies from women urogenitally infected with C. trachomatis predominantly recognized the plasmid protein pgp3 in a conformation-dependent manner

    Directory of Open Access Journals (Sweden)

    Wu Yimou

    2008-06-01

    Full Text Available Abstract Background C. trachomatis organisms carry a cryptic plasmid that encodes 8 open reading frames designated as pORF1 to 8. It is not clear whether all 8 pORFs are expressed during C. trachomatis infection in humans and information on the functionality of the plasmid proteins is also very limited. Results When antibodies from women urogenitally infected with C. trachomatis were reacted with the plasmid proteins, all 8 pORFs were positively recognized by one or more human antibody samples with the recognition of pORF5 protein (known as pgp3 by most antibodies and with the highest titers. The antibody recognition of the pORFs was blocked by C. trachomatis-infected HeLa but not normal HeLa cell lysates. The pgp3 fusion protein-purified human IgG detected the endogenous pgp3 in the cytosol of C. trachomatis-infected cells with an intracellular distribution pattern similar to that of CPAF, a chlamydial genome-encoded protease factor. However, the human antibodies no longer recognized pgp3 but maintained recognition of CPAF when both antigens were linearized or heat-denatured. The pgp3 conformation is likely maintained by the C-terminal 75% amino acid sequence since further deletion blocked the binding by the human antibodies and two conformation-dependent mouse monoclonal antibodies. Conclusion The plasmid-encoded 8 proteins are both expressed and immunogenic with pgp3 as the most immunodominant antigen during chlamydial infection in humans. More importantly, the human anti-pgp3 antibodies are highly conformation-dependent. These observations have provided important information for further understanding the function of the plasmid-encoded proteins and exploring the utility of pgp3 in chlamydial diagnosis and vaccination.

  14. Kinetic Characterisation of a Single Chain Antibody against the Hormone Abscisic Acid: Comparison with Its Parental Monoclonal

    Science.gov (United States)

    Badescu, George O.; Marsh, Andrew; Smith, Timothy R.; Thompson, Andrew J.; Napier, Richard M.

    2016-01-01

    A single-chain Fv fragment antibody (scFv) specific for the plant hormone abscisic acid (ABA) has been expressed in the bacterium Escherichia coli as a fusion protein. The kinetics of ABA binding have been measured using surface plasmon resonance spectrometry (BIAcore 2000) using surface and solution assays. Care was taken to calculate the concentration of active protein in each sample using initial rate measurements under conditions of partial mass transport limitation. The fusion product, parental monoclonal antibody and the free scFv all have low nanomolar affinity constants, but there is a lower dissociation rate constant for the parental monoclonal resulting in a three-fold greater affinity. Analogue specificity was tested and structure-activity binding preferences measured. The biologically-active (+)-ABA enantiomer is recognised with an affinity three orders of magnitude higher than the inactive (-)-ABA. Metabolites of ABA including phaseic acid, dihydrophaseic acid and deoxy-ABA have affinities over 100-fold lower than that for (+)-ABA. These properties of the scFv make it suitable as a sensor domain in bioreporters specific for the naturally occurring form of ABA. PMID:27023768

  15. Kinetic Characterisation of a Single Chain Antibody against the Hormone Abscisic Acid: Comparison with Its Parental Monoclonal.

    Directory of Open Access Journals (Sweden)

    George O Badescu

    Full Text Available A single-chain Fv fragment antibody (scFv specific for the plant hormone abscisic acid (ABA has been expressed in the bacterium Escherichia coli as a fusion protein. The kinetics of ABA binding have been measured using surface plasmon resonance spectrometry (BIAcore 2000 using surface and solution assays. Care was taken to calculate the concentration of active protein in each sample using initial rate measurements under conditions of partial mass transport limitation. The fusion product, parental monoclonal antibody and the free scFv all have low nanomolar affinity constants, but there is a lower dissociation rate constant for the parental monoclonal resulting in a three-fold greater affinity. Analogue specificity was tested and structure-activity binding preferences measured. The biologically-active (+-ABA enantiomer is recognised with an affinity three orders of magnitude higher than the inactive (--ABA. Metabolites of ABA including phaseic acid, dihydrophaseic acid and deoxy-ABA have affinities over 100-fold lower than that for (+-ABA. These properties of the scFv make it suitable as a sensor domain in bioreporters specific for the naturally occurring form of ABA.

  16. Oriented antibody immobilization to polystyrene macrocarriers for immunoassay modified with hydrazide derivatives of poly(methacrylic acid

    Directory of Open Access Journals (Sweden)

    Vinokurova Ludmila G

    2001-08-01

    Full Text Available Abstract Background Hydrophobic polystyrene is the most common material for solid phase immunoassay. Proteins are immobilized on polystyrene by passive adsorption, which often causes considerable denaturation. Biological macromolecules were found to better retain their functional activity when immobilized on hydrophilic materials. Polyacrylamide is a common material for solid-phase carriers of biological macromolecules, including immunoreagents used in affinity chromatography. New macroformats for immunoassay modified with activated polyacrylamide derivatives seem to be promising. Results New polymeric matrices for immunoassay in the form of 0.63-cm balls which contain hydrazide functional groups on hydrophilic polymer spacer arms at their surface shell are synthesized by modification of aldehyde-containing polystyrene balls with hydrazide derivatives of poly(methacrylic acid. The beads contain up to 0.31 μmol/cm2 active hydrazide groups accessible for covalent reaction with periodate-oxidized antibodies. The matrices obtained allow carrying out the oriented antibody immobilization, which increases the functional activity of immunosorbents. Conclusions An efficient site-directed antibody immobilization on a macrosupport is realized. The polymer hydrophilic spacer arms are the most convenient and effective tools for oriented antibody coupling with molded materials. The suggested scheme can be used for the modification of any other solid supports containing electrophilic groups reacting with hydrazides.

  17. Increasing the sensitivity of reverse phase protein arrays by antibody-mediated signal amplification

    Directory of Open Access Journals (Sweden)

    Brase Jan C

    2010-06-01

    Full Text Available Abstract Background Reverse phase protein arrays (RPPA emerged as a useful experimental platform to analyze biological samples in a high-throughput format. Different signal detection methods have been described to generate a quantitative readout on RPPA including the use of fluorescently labeled antibodies. Increasing the sensitivity of RPPA approaches is important since many signaling proteins or posttranslational modifications are present at a low level. Results A new antibody-mediated signal amplification (AMSA strategy relying on sequential incubation steps with fluorescently-labeled secondary antibodies reactive against each other is introduced here. The signal quantification is performed in the near-infrared range. The RPPA-based analysis of 14 endogenous proteins in seven different cell lines demonstrated a strong correlation (r = 0.89 between AMSA and standard NIR detection. Probing serial dilutions of human cancer cell lines with different primary antibodies demonstrated that the new amplification approach improved the limit of detection especially for low abundant target proteins. Conclusions Antibody-mediated signal amplification is a convenient and cost-effective approach for the robust and specific quantification of low abundant proteins on RPPAs. Contrasting other amplification approaches it allows target protein detection over a large linear range.

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

    Directory of Open Access Journals (Sweden)

    Setyawan P. Sakti

    2016-01-01

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

  19. Purification of mitochondrial proteins HSP60 and ATP synthase from ascidian eggs: implications for antibody specificity.

    Directory of Open Access Journals (Sweden)

    Janet Chenevert

    Full Text Available Use of antibodies is a cornerstone of biological studies and it is important to identify the recognized protein with certainty. Generally an antibody is considered specific if it labels a single band of the expected size in the tissue of interest, or has a strong affinity for the antigen produced in a heterologous system. The identity of the antibody target protein is rarely confirmed by purification and sequencing, however in many cases this may be necessary. In this study we sought to characterize the myoplasm, a mitochondria-rich domain present in eggs and segregated into tadpole muscle cells of ascidians (urochordates. The targeted proteins of two antibodies that label the myoplasm were purified using both classic immunoaffinity methods and a novel protein purification scheme based on sequential ion exchange chromatography followed by two-dimensional gel electrophoresis. Surprisingly, mass spectrometry sequencing revealed that in both cases the proteins recognized are unrelated to the original antigens. NN18, a monoclonal antibody which was raised against porcine spinal cord and recognizes the NF-M neurofilament subunit in vertebrates, in fact labels mitochondrial ATP synthase in the ascidian embryo. PMF-C13, an antibody we raised to and purified against PmMRF, which is the MyoD homolog of the ascidian Phallusia mammillata, in fact recognizes mitochondrial HSP60. High resolution immunolabeling on whole embryos and isolated cortices demonstrates localization to the inner mitochondrial membrane for both ATP synthase and HSP60. We discuss the general implications of our results for antibody specificity and the verification methods which can be used to determine unequivocally an antibody's target.

  20. Cloning of neuromedin B and its receptor in the rabbit and generating a polyclonal antibody to the neuromedin B protein.

    Science.gov (United States)

    Guo, Ting-Ting; Su, Juan; Ma, Zhi-Yu; Ma, Jun-Xiao; Jin, Meng-Meng; Li, Xiang; Lei, Zhi-Hai

    2015-06-10

    Neuromedin B (NMB) is a highly conserved bombesin-related neuropeptide found in mammals. Neuromedin B (NMB) executes its effect by binding to the cell surface receptor, neuromedin B receptor (NMBR). In this study, we cloned the rabbit NMB and NMBR genes. The similarity and phylogenetic analyses of NMB and NMBR gene sequences were performed. The expression of NMB and NMBR mRNA in the rabbit was investigated using real-time RT-PCR. Our bioinformatic analysis demonstrated that the cloned rabbit NMB precursor cDNA encoded Gly-His-Phe-Met-NH2 amino acids at the C-terminus, and that its receptor possessed typical transmembrane features. The NMB mRNA was highly expressed in the CNS, while the NMBR mRNA was widely expressed in many tissues, with the highest expression in the gastrointestinal tract. The studies on the NMB distribution and function are limited by the lack of a specific antibody to this neuropeptide. In this paper, polyclonal NMB antibody was generated in mice. Western blotting analysis revealed that the prepared antibody could specifically recognize the recombinant and the endogenous NMB proteins. Immunohistochemistry analysis indicated that the NMB protein was localized in the cytoplasm of the pituitary cells. The existence of NMB protein in the hypothalamic-pituitary-gonadal axis suggests that NMB might function in rabbit reproduction. PMID:25796599

  1. Anchoring of proteins to lactic acid bacteria

    NARCIS (Netherlands)

    Leenhouts, K; Buist, Girbe; Kok, Jan

    1999-01-01

    The anchoring of proteins to the cell surface of lactic acid bacteria (LAB) using genetic techniques is an exciting and emerging research area that holds great promise for a wide variety of biotechnological applications. This paper reviews five different types of anchoring domains that have been exp

  2. A new method for measuring antibody using radiolabeled protein A in a solid-phase radioimmunoassay

    International Nuclear Information System (INIS)

    A micro solid-phase radioimmunoassay was developed which utilizes radiolabeled staphylococcal Protein A ([125I] Protein A) in place of radiolabeled anti-immunoglobulin ([125I]anti-IgG) for the measurement of antibody. For the assay, antigen is adsorbed to the wells of a microtiter plate followed by dilutions of serum and [125I]-Protein A in subsequent steps. It was found that this assay can be used to measure antibody (Ab) against a variety of antigens in human and rabbit but not goat immune serum. Binding of [125I]-Protein A and [125I]anti-IgG to human and rabbit IgG was comparable. It was possible to quantify this amount of Ab in human serum by reference to immune rabbit serum. The sensitivity of this assay for rabbit antibody was 1 ng/ml. (Auth.)

  3. Prion Protein-specific antibodies that detect multiple TSE Agents with high sensitivity

    NARCIS (Netherlands)

    McCutcheon, S.; Langeveld, J.P.M.; Tan, B.C.; Gill, A.C.; Wolf, de C.A.; Martin, S.; Gonzalez, L.; Alibhai, J.; Alejo Blanco, A.R.; Campbell, L.; Hunter, N.; Houston, E.F.

    2014-01-01

    This paper describes the generation, characterisation and potential applications of a panel of novel anti-prion protein monoclonal antibodies (mAbs). The mAbs were generated by immunising PRNP null mice, using a variety of regimes, with a truncated form of recombinant ovine prion protein spanning re

  4. B-1 cells and naturally occuring antibodies: influencing the immunogenicity of recombinant human therapeutic proteins

    NARCIS (Netherlands)

    Sauerborn, M.S.; Schellekens, H.

    2009-01-01

    Recombinant human therapeutic proteins are increasingly being used to treat serious and life-threatening diseases like multiple sclerosis, diabetes mellitus, and cancer. An important side effect of these proteins is the development of antidrug antibodies, which can be neutralizing and thus interfere

  5. Identification of discriminant proteins through antibody profiling, methods and apparatus for identifying an individual

    Energy Technology Data Exchange (ETDEWEB)

    Apel, William A.; Thompson, Vicki S; Lacey, Jeffrey A.; Gentillon, Cynthia A.

    2016-08-09

    A method for determining a plurality of proteins for discriminating and positively identifying an individual based from a biological sample. The method may include profiling a biological sample from a plurality of individuals against a protein array including a plurality of proteins. The protein array may include proteins attached to a support in a preselected pattern such that locations of the proteins are known. The biological sample may be contacted with the protein array such that a portion of antibodies in the biological sample reacts with and binds to the proteins forming immune complexes. A statistical analysis method, such as discriminant analysis, may be performed to determine discriminating proteins for distinguishing individuals. Proteins of interest may be used to form a protein array. Such a protein array may be used, for example, to compare a forensic sample from an unknown source with a sample from a known source.

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

    Directory of Open Access Journals (Sweden)

    Darragh Lemass

    2016-01-01

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

  7. Alimentary proteins, amino acids and cholesterolemia.

    Science.gov (United States)

    Blachier, François; Lancha, Antonio H; Boutry, Claire; Tomé, Daniel

    2010-01-01

    Numerous data from both epidemiological and experimental origins indicate that some alimentary proteins and amino acids in supplements can modify the blood LDL cholesterol, HDL cholesterol and total cholesterol. After an initial approval of the health claim for soy protein consumption for the prevention of coronary heart disease, more recently it has been concluded from an overall analysis of literature that isolated soy protein with isoflavones only slightly decrease LDL and total cholesterol. Other plant extracts and also some proteins from animal origin have been reported to exert a lowering effect on blood cholesterol when compared with a reference protein (often casein). The underlying mechanisms are still little understood. Individual amino acids and mixture of amino acids have also been tested (mostly in animal studies) for their effects on cholesterol parameters and on cholesterol metabolism. Methionine, lysine, cystine, leucine, aspartate and glutamate have been tested individually and in combination in different models of either normo or hypercholesterolemic animals and found to be able to modify blood cholesterol and/or LDL cholesterol and/or HDL cholesterol. It is however not known if these results are relevant to human nutrition.

  8. Functional Activity of Antibodies Directed towards Flagellin Proteins of Non-Typhoidal Salmonella.

    Science.gov (United States)

    Ramachandran, Girish; Tennant, Sharon M; Boyd, Mary A; Wang, Jin Y; Tulapurkar, Mohan E; Pasetti, Marcela F; Levine, Myron M; Simon, Raphael

    2016-01-01

    Non-typhoidal Salmonella (NTS) serovars Typhimurium and Enteritidis are major causes of invasive bacterial infections in children under 5 years old in sub-Saharan Africa, with case fatality rates of ~20%. There are no licensed NTS vaccines for humans. Vaccines that induce antibodies against a Salmonella Typhi surface antigen, Vi polysaccharide, significantly protect humans against typhoid fever, establishing that immune responses to Salmonella surface antigens can be protective. Flagella proteins, abundant surface antigens in Salmonella serovars that cause human disease, are also powerful immunogens, but the functional capacity of elicited anti-flagellar antibodies and their role in facilitating bacterial clearance has been unclear. We examined the ability of anti-flagellar antibodies to mediate microbial killing by immune system components in-vitro and assessed their role in protecting mice against invasive Salmonella infection. Polyclonal (hyperimmune sera) and monoclonal antibodies raised against phase 1 flagellin proteins of S. Enteritidis and S. Typhimurium facilitated bacterial uptake and killing of the homologous serovar pathogen by phagocytes. Polyclonal anti-flagellar antibodies accompanied by complement also achieved direct bacterial killing. Serum bactericidal activity was restricted to Salmonella serovars expressing the same flagellin used as immunogen. Notably, individual anti-flagellin monoclonal antibodies with complement were not bactericidal, but this biological activity was restored when different monoclonal anti-flagellin antibodies were combined. Passive transfer immunization with a monoclonal IgG antibody specific for phase 1 flagellin from S. Typhimurium protected mice against lethal challenge with a representative African invasive S. Typhimurium strain. These findings have relevance for the use of flagellin proteins in NTS vaccines, and confirm the role of anti-flagellin antibodies as mediators of protective immunity.

  9. Functional Activity of Antibodies Directed towards Flagellin Proteins of Non-Typhoidal Salmonella.

    Directory of Open Access Journals (Sweden)

    Girish Ramachandran

    Full Text Available Non-typhoidal Salmonella (NTS serovars Typhimurium and Enteritidis are major causes of invasive bacterial infections in children under 5 years old in sub-Saharan Africa, with case fatality rates of ~20%. There are no licensed NTS vaccines for humans. Vaccines that induce antibodies against a Salmonella Typhi surface antigen, Vi polysaccharide, significantly protect humans against typhoid fever, establishing that immune responses to Salmonella surface antigens can be protective. Flagella proteins, abundant surface antigens in Salmonella serovars that cause human disease, are also powerful immunogens, but the functional capacity of elicited anti-flagellar antibodies and their role in facilitating bacterial clearance has been unclear. We examined the ability of anti-flagellar antibodies to mediate microbial killing by immune system components in-vitro and assessed their role in protecting mice against invasive Salmonella infection. Polyclonal (hyperimmune sera and monoclonal antibodies raised against phase 1 flagellin proteins of S. Enteritidis and S. Typhimurium facilitated bacterial uptake and killing of the homologous serovar pathogen by phagocytes. Polyclonal anti-flagellar antibodies accompanied by complement also achieved direct bacterial killing. Serum bactericidal activity was restricted to Salmonella serovars expressing the same flagellin used as immunogen. Notably, individual anti-flagellin monoclonal antibodies with complement were not bactericidal, but this biological activity was restored when different monoclonal anti-flagellin antibodies were combined. Passive transfer immunization with a monoclonal IgG antibody specific for phase 1 flagellin from S. Typhimurium protected mice against lethal challenge with a representative African invasive S. Typhimurium strain. These findings have relevance for the use of flagellin proteins in NTS vaccines, and confirm the role of anti-flagellin antibodies as mediators of protective immunity.

  10. [Preparation and detection of anti-influenza A virus polymerase basic protein 1 polyclonal antibody].

    Science.gov (United States)

    Qin, Yujie; Zhang, Tinghong; Ye, Xin

    2016-01-01

    Influenza A virus is an enveloped virus that belongs to the Orthomyxoviridae family. It has 8 negative RNA segments that encode 16 viral proteins. The viral polymerase consists of 3 proteins (PB 1, PB2 and PA) which plays an important role in the transcription and replication of the influenza A virus. Polymerase basic protein 1 (PB 1) is a critical member of viral polymerase complex. In order to further study the function of PB1, we need to prepare the PB1 antibody with good quality. Therefore, we amplified PB1 conserved region (nt1648-2265) by PCR and cloned it into pET-30a vector, and transformed into Escherichia coli BL2 1. The expression of His tagged PB 1 protein was induced by IPTG, and His-PB 1 proteins were purified by Ni-NTA resin. For preparation of PB 1 protein antiserum, rabbits were immunized with His-PB 1 fusion protein 3 times. Then the titer of PB 1 polyclonal antibody was measured by indirect ELISA. The antibody was purified by membrane affinity purification and subjected to immunoblotting analysis. Data showed that PB1 antibody can recognize PB 1 protein from WSN virus infected or pCMV FLAG-PB 1 transfected cells. Meanwhile, PB 1 antibody can also recognize specifically other subtype strains of influenza A virus such as H9N2 and H3N2. PB 1 polyclonal antibody we generated will be a useful tool to study the biological function of PB1. PMID:27363203

  11. Murine carcinoma expressing carcinoembryonic antigen-like protein is restricted by antibody against neem leaf glycoprotein.

    Science.gov (United States)

    Das, Arnab; Barik, Subhasis; Bose, Anamika; Roy, Soumyabrata; Biswas, Jaydip; Baral, Rathindranath; Pal, Smarajit

    2014-11-01

    We have generated a polyclonal antibody against a novel immunomodulator, neem leaf glycoprotein (NLGP) that can react to a specific 47 kDa subunit of NLGP. Generated anti-NLGP antibody (primarily IgG2a) was tested for its anti-tumor activity in murine carcinoma (EC, CT-26), sarcoma (S180) and melanoma (B16Mel) tumor models. Surprisingly, tumor growth restriction was only observed in CT-26 carcinoma models, without any alteration in other tumor systems. Comparative examination of antigenicity between four different tumor models revealed high expression of CEA-like protein on the surface of CT-26 tumors. Subsequent examination of the cross-reactivity of anti-NLGP antibody with purified or cell bound CEA revealed prominent recognition of CEA by anti-NLGP antibody, as detected by ELISA, Western Blotting and immunohistochemistry. This recognition seems to be responsible for anti-tumor function of anti-NLGP antibody only on CEA-like protein expressing CT-26 tumor models, as confirmed by ADCC reaction in CEA(+) tumor systems where dependency to anti-NLGP antibody is equivalent to anti-CEA antibody. Obtained result with enormous therapeutic potential for CEA(+) tumors may be explained in view of the epitope spreading concept, however, further investigation is crucial.

  12. Rituximab in treatment-resistant CIDP with antibodies against paranodal proteins

    OpenAIRE

    Querol, Luis; Rojas-García, Ricard; Diaz-Manera, Jordi; Barcena, Joseba; Pardo, Julio; Ortega-Moreno, Angel; Sedano, Maria Jose; Seró-Ballesteros, Laia; Carvajal, Alejandra; Ortiz, Nicolau; Gallardo, Eduard; Illa, Isabel

    2015-01-01

    Objective: To describe the response to rituximab in patients with treatment-resistant chronic inflammatory demyelinating polyneuropathy (CIDP) with antibodies against paranodal proteins and correlate the response with autoantibody titers. Methods: Patients with CIDP and IgG4 anti–contactin-1 (CNTN1) or anti–neurofascin-155 (NF155) antibodies who were resistant to IV immunoglobulin and corticosteroids were treated with rituximab and followed prospectively. Immunocytochemistry was used to detec...

  13. Production of Antibodies against Multipass Membrane Proteins Expressed in Human Tumor Cells Using Dendritic Cell Immunization

    OpenAIRE

    Takahiko Tamura; Joe Chiba

    2009-01-01

    Antibody mediated therapeutic strategies against human malignant tumors have been widely authorized and clinically applied to cancer patients. In order to develop methods to generate antibodies reactive to the extracellular domains of multipass plasma membrane proteins specifically expressed in malignant tumors, we examined the use of dendritic cells (DCs) for immunization. DCs were transduced with genes encoding the human six transmembrane epithelial antigen of prostate 1 (STEAP1), STEAP4, a...

  14. Circulating antibody to myelin basic protein in relapsing-remitting multiple sclerosis

    International Nuclear Information System (INIS)

    Sera from multiple sclerosis patients with relapsing-remitting disease and normal subjects were tested for antibody to myelin basic protein by a sensitive radioimmunoassay. The results showed a marginally decreased titre in multiple sclerosis superimposed on a seasonal variation. There was no correlation with the clinical state of the patients. Results are discussed briefly in relation to humoral antibody function in multiple sclerosis and experimental autoimmune encephalitis. (author)

  15. Protein Delivery of Thymidylate Kinase Mediated by Tumor-Specific Antibody-Precoated Microvesicles.

    Science.gov (United States)

    Mohammadzadeh-Vardin, Mohammad; Panahpour, Hamdollah; Golmohammadi, Mohammad Ghasem; Sagha, Mohsen

    2016-01-01

    Molecular targeted therapy is an important, novel approach in the treatment of cancer because it interferes with certain molecules involved in carcinogenesis and tumor growth. Examples include monoclonal antibodies, microvesicles, and suicide genes. Several studies have focused on targeted therapies in prostate cancer, which is a serious cause of cancer death in men. We hypothesize that antibody-coated microvesicles can deliver thymidylate kinase, a suicide protein, to prostate cancer cells, potentiating them to death following azidothymidine (AZT) treatment. PMID:27278881

  16. Rainbow trout surviving infections of viral haemorrhagic septicemia virus (VHSV) show lasting antibodies to recombinant G protein fragments

    DEFF Research Database (Denmark)

    Encinas, P.; Gomez-Casado, E.; Grandes, Fregeneda;

    2011-01-01

    Rainbow trout antibodies (Abs) binding to recombinant fragments (frgs) derived from the protein G of the viral haemorrhagic septicemia virus (VHSV)-07.71 strain, could be detected by ELISA (frg-ELISA) in sera from trout surviving laboratory-controlled infections. Abs were detected not only by using...... sera from trout infected with the homologous VHSV isolate but also with the VHSV-DK-201433 heterologous isolate, which had 13 amino acid changes. Sera from healthy trout and/or from trout surviving infectious haematopoietic necrosis virus (IHNV) infection, were used to calculate cut-off absorbances...

  17. Coupling of antibodies via protein Z on modified polyoma virus-like particles

    OpenAIRE

    Gleiter, Stefan; Lilie, Hauke

    2001-01-01

    Therapeutic application of virus-based delivery systems often implies a change of the tropism of these vectors. This can be achieved by insertion of polypeptides (e.g., antibody fragments) in viral coat proteins. Such fusion proteins have only been used in viral vectors so far and, as part of a virus, they have not been available for a detailed biophysical characterization. We analyzed a fusion protein called VP1-Z, which is based on the polyoma virus coat protein VP1 and protein Z. Protein Z...

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

    Science.gov (United States)

    Hoekstra, Gabriel; Yi, Xianwen; Stone, Michelle; Horvath, Katie; Miley, Michael J.; DeSimone, Joseph; Luft, Chris J.; de Silva, Aravinda M.

    2016-01-01

    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. PMID:27764114

  19. Construction and Analysis of Three-dimensional Graphic Model of Single-chain Fv Derived from an Anti-human Placental Acidic Isoferritin Monoclonal Antibody by Computer

    Institute of Scientific and Technical Information of China (English)

    ZHOU Chun; SHEN Guanxin; ZHU Huifen; YANG Jing; ZHANG Yue; FENG Jiannan; SHEN Beifen

    2000-01-01

    A three-dimensional (3D) graphic model of a single-chain Fv (scFv) which was derived from an anti-human placental acidic isoferritin (PAF) monoclonal antibody (Mab) was constructed by a homologous protein-predicting computer algorithm on Silicon graphic computer station.The structure, surface static electricity and hydrophobicity of scFv were investigated. Computer graphic modelling indicated that all regions of scFv including the linker, variable regions of the heavy (VH) and light (VL) chains were suitable. The VH region and the VL region were involved in composing the "hydrophobic pocket". The linker was drifted away VH and VL regions. The complementarity determining regions (CDRs) of VH and VL regions surrounded the "hydrophobic pocket". This study provides a theory basis for improving antibody affinity, investigating antibody structure and analyzing the functions of VH and VL regions in antibody activity.

  20. Antibodies against Ku protein in sera from patients with autoimmune diseases.

    Science.gov (United States)

    Yaneva, M; Arnett, F C

    1989-01-01

    Immunoaffinity-purified Ku protein was used to screen sera from patients with systemic lupus erythematosus (SLE), scleroderma, myositis and Sjögren's syndrome for anti-Ku antibodies in a quantitative immunoblot assay. Sixteen percent of the 159 studied sera were reactive with the Ku protein; significantly increased frequencies of anti-Ku antibodies were found in SLE (19%) and scleroderma (14%) sera. Patients with myositis and Sjögren's syndrome showed similar frequencies. All positive sera had antibodies to the 86 kD subunit of Ku protein; only one serum did not react with 70 kD subunit. Frequencies of other autoantibodies were compared in anti-Ku positive and negative patients. Only anti-Sm antibodies, especially in the absence of anti-nRNP, appear to be associated with the presence of anti-Ku antibodies. A strong correlation between anti-Ku antibodies and the class II HLA antigen DQw1 (89% of the positive sera) was observed, suggesting participation of MHC genes in the mounting of the anti-Ku immune response. Images Fig. 1 Fig. 2 PMID:2665976

  1. Detection of TGEV Antibody by Enzyme-Linked Immunosorbent Assay Using Recombinant Nucleocapsid Proteins

    Institute of Scientific and Technical Information of China (English)

    YU Li-yun; HOU Xi-lin

    2005-01-01

    An enzyme linked immunosorbent assays (ELISA) based on recombinant nucleocapsid (N) protein generated in Escherichia coli was evaluated for its sensitivity and specificity for diagnosis of transmissible gastroenteritis virus (TGEV) infection.The N gene encoding the N protein was cloned and expressed as a fusion protein with His tag protein in E. coli. The recombinant N protein migrated at 42 kDa and reacted with His6 tag specific monoclonal antibody by immunoblotting.Recombinant N protein ELISA (rnELISA) demonstrated 97.5% specificity among 80 TGEV-free individuals, and 97.3%sensitivity ranging among 110 clinical samples with TGEV. Taken together, these results indicated that nucleocapsid may be a useful antigen for the sera-diagnosis of TGEV and it was also suggested that the ELISA is a highly sensitive and specific test for detecting antibodies against TGEV.

  2. Tumour auto-antibody screening: performance of protein microarrays using SEREX derived antigens

    International Nuclear Information System (INIS)

    The simplicity and potential of minimal invasive testing using serum from patients make auto-antibody based biomarkers a very promising tool for use in diagnostics of cancer and auto-immune disease. Although several methods exist for elucidating candidate-protein markers, immobilizing these onto membranes and generating so called macroarrays is of limited use for marker validation. Especially when several hundred samples have to be analysed, microarrays could serve as a good alternative since processing macro membranes is cumbersome and reproducibility of results is moderate. Candidate markers identified by SEREX (serological identification of antigens by recombinant expression cloning) screenings of brain and lung tumour were used for macroarray and microarray production. For microarray production recombinant proteins were expressed in E. coli by autoinduction and purified His-tag (histidine-tagged) proteins were then used for the production of protein microarrays. Protein arrays were hybridized with the serum samples from brain and lung tumour patients. Methods for the generation of microarrays were successfully established when using antigens derived from membrane-based selection. Signal patterns obtained by microarrays analysis of brain and lung tumour patients' sera were highly reproducible (R = 0.92-0.96). This provides the technical foundation for diagnostic applications on the basis of auto-antibody patterns. In this limited test set, the assay provided high reproducibility and a broad dynamic range to classify all brain and lung samples correctly. Protein microarray is an efficient means for auto-antibody-based detection when using SEREX-derived clones expressing antigenic proteins. Protein microarrays are preferred to macroarrays due to the easier handling and the high reproducibility of auto-antibody testing. Especially when using only a few microliters of patient samples protein microarrays are ideally suited for validation of auto-antibody

  3. Immune response in mice to ingested soya protein: antibody production, oral tolerance and maternal transfer.

    Science.gov (United States)

    Christensen, Hanne R; Brix, Susanne; Frøkiaer, Hanne

    2004-05-01

    While allergic reactions to soya are increasingly investigated, the normal immune response to ingested soya is scarcely described. In the present study, we wanted to characterise the soya-specific immune response in healthy mice ingesting soya protein. Mice fed a soya-containing diet (F0) and mice of the first (F1) and second (F2) offspring generation bred on a soya protein-free diet were used either directly or were transferred between the soya-containing and soya protein-free diet during pregnancy or neonatal life. The mice were compared as to levels of naturally occurring specific antibodies analysed by ELISA, and to the presence of oral tolerance detected as a suppressed antibody and cell-proliferation response upon immunisation with soya protein. F0 mice generated soya-specific antibodies, while oral tolerance to the same soya proteins was also clearly induced. When F0 dams were transferred to soya protein-free feed before mating, the F1 and F2 offspring generations showed no significantly different response, indicating that soya-specific immune components were not maternally transmitted. However, the ingestion of dietary soya protein by F1 mice during late pregnancy and lactation caused a lasting antibody response in the offspring, but in this case in the absence of oral tolerance. This indicates that, under certain conditions, factors involved in spontaneous antibody production can be transmitted from mother to offspring. Understanding the immune response to soya protein ingested under healthy conditions is important in the assessment of adverse effects of soya protein and in the use of animal allergy models. The present results add to this understanding. PMID:15137924

  4. Preparation and identification of monoclonal antibody against liver fatty acid binding protein%肝脏型脂肪酸结合蛋白的重组表达及其单克隆抗体的制备和鉴定

    Institute of Scientific and Technical Information of China (English)

    宋巍; 杨海波; 陈兰英

    2014-01-01

    目的:制备抗肝脏型脂肪酸结合蛋白(LFABP)的单克隆抗体(mAb)并进行亚型和特异性鉴定。方法:以重组的LFABP蛋白为免疫原,经过原核表达和纯化后,免疫BALB/c小鼠,获得分泌鼠抗人LFABP蛋白mAb的杂交瘤细胞株,通过ELISA和Western blot方法检测其特异性。结果:纯化的LFABP重组蛋白免疫小鼠后经过筛选得到2株稳定分泌抗人LFABP的mAb杂交瘤细胞株,分别命名为3E6和5B7,其亚型分别为IgG1和IgG2a,抗体经纯化后浓度达到2 mg/mL,效价达到1∶10000以上。Western blot分析结果表明可与细胞中表达的内源LFABP发生特异性免疫反应。结论:成功制备了鼠抗人LFABP的mAb,为进一步研究LFABP的生物学特性,并为相关疾病的治疗奠定了基础。%OBJECTIVE:To prepare anti-liver-type fatty acid binding protein (LFABP) monoclonal antibody (mAb) and identified subtype and specificity. METHODS:The LFABP recombinant protein was used to immunize BALB/c mice,spleen cells from immunized mice were fused with myeloma cell Sp2/0. After HAT selective culture and indirect ELISA screening,we obtained hybridoma cell line secreting mouse mAb against human LFABP. The specificity was verified by ELISA and Western blotting. RESULTS:After using purified recombinant protein immunized mice and screening,we obtained two hybridoma cell lines secreting the mAb against human LFABP,named 3E6 and 5B7,both were of the IgG1 subtype. The antibody was purified,reaching a concentration of 2 mg/mL,and titer of 1∶10 000 above. Western blotting showed that mAb had a specific reaction with the LFABP endogenous expression in the cells. CONCLUSION:We successfully prepared mice mAb against human LFABP ,which could not only provide an important foundation to further studies of the biological characteristics of LFABP,mechanism involved in regulation of fatty acid metabolism and drug interaction,but also provide experimental evidence for the treatment

  5. 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)

    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.

  6. Protein and Amino Acid Requirements during Pregnancy.

    Science.gov (United States)

    Elango, Rajavel; Ball, Ronald O

    2016-07-01

    Protein forms an essential component of a healthy diet in humans to support both growth and maintenance. During pregnancy, an exceptional stage of life defined by rapid growth and development, adequate dietary protein is crucial to ensure a healthy outcome. Protein deposition in maternal and fetal tissues increases throughout pregnancy, with most occurring during the third trimester. Dietary protein intake recommendations are based on factorial estimates because the traditional method of determining protein requirements, nitrogen balance, is invasive and undesirable during pregnancy. The current Estimated Average Requirement and RDA recommendations of 0.88 and 1.1 g · kg(-1) · d(-1), respectively, are for all stages of pregnancy. The single recommendation does not take into account the changing needs during different stages of pregnancy. Recently, with the use of the minimally invasive indicator amino acid oxidation method, we defined the requirements to be, on average, 1.2 and 1.52 g · kg(-1) · d(-1) during early (∼16 wk) and late (∼36 wk) stages of pregnancy, respectively. Although the requirements are substantially higher than current recommendations, our values are ∼14-18% of total energy and fit within the Acceptable Macronutrient Distribution Range. Using swine as an animal model we showed that the requirements for several indispensable amino acids increase dramatically during late gestation compared with early gestation. Additional studies should be conducted during pregnancy to confirm the newly determined protein requirements and to determine the indispensable amino acid requirements during pregnancy in humans. PMID:27422521

  7. High throughput identification of monoclonal antibodies to membrane bound and secreted proteins using yeast and phage display.

    Directory of Open Access Journals (Sweden)

    Lequn Zhao

    Full Text Available Antibodies are ubiquitous and essential reagents for biomedical research. Uses of antibodies include quantifying proteins, identifying the temporal and spatial pattern of expression in cells and tissue, and determining how proteins function under normal or pathological conditions. Specific antibodies are only available for a small portion of the proteome, limiting study of those proteins for which antibodies do not exist. The technologies to generate target-specific antibodies need to be improved to obtain high quality antibodies to the proteome at reasonable cost. Here we show that renewable, validated, and standardized monoclonal antibodies can be generated at high throughput, without the need for antigen production or animal immunizations. In this study, 60 protein domains from 24 selected secreted proteins were expressed on the surface of yeast and used for selection of phage antibodies, over 400 monoclonal antibodies were identified within 3 weeks. A subset of these antibodies was validated for binding to cancer cells that overexpress the target protein by flow cytometry or immunohistochemistry. This approach will be applicable to many of the membrane-bound and the secreted proteins, 20-40% of the proteome, accelerating the timeline for Ab generation while reducing the cost.

  8. A monoclonal antibody for G protein-coupled receptor crystallography

    DEFF Research Database (Denmark)

    Day, Peter W; Rasmussen, Søren Gøgsig Faarup; Parnot, Charles;

    2007-01-01

    G protein-coupled receptors (GPCRs) constitute the largest family of signaling proteins in mammals, mediating responses to hormones, neurotransmitters, and senses of sight, smell and taste. Mechanistic insight into GPCR signal transduction is limited by a paucity of high-resolution structural inf...

  9. Elimination of islet cell antibodies and glutamic acid decarboxylase antibodies II in a patient with newly diagnosed insulin-dependent diabetes mellitus.

    Science.gov (United States)

    Richter, W O; Donner, M G; Schwandt, P

    1997-01-01

    Islet cell antibodies and glutamic acid decarboxylase II (GAD II) antibodies have been discussed in the autoimmune pathogenesis of insulin-dependent diabetes mellitus (IDDM). Hence, immunosuppressants, intravenous immunoglobulins, and plasmapheresis have been used in an effort to modulate autoimmune activity and thereby prevent the destruction of pancreatic beta-cells. We describe the autoantibody (islet cell antibody and GAD II) kinetics and clinical course in a patient with newly diagnosed IDDM treated with a specific immunoglobulin apheresis technique. Five days after the initial diagnosis a 37-year-old patient with IDDM underwent a series of seven immunoglobulin aphereses. Immunoglobulin (IgG, IgA, IgM), islet cell antibody, GAD II, and C-peptide concentrations were monitored for a time course of 74 days. Daily insulin requirements were recorded. One single immunoglobulin apheresis decreased IgG by 66.2 +/- 9.1%, IgA by 66.8 +/- 8.7%, and IgM by 57.7 +/- 12.9%. GAD II antibodies were reduced by 61.9 +/- 12.4%. The islet cell antibody titer declined from 1:32 to 1:4 after the treatment series. There were no relevant changes in the safety parameters determined nor were there any clinical side effects. The efficient decrease in islet cell antibodies and glutamic acid decarboxylase II antibodies in a patient with IDDM encourages further investigations into the impact of this treatment on the clinical course of this autoimmune disorder.

  10. Comparison of different monoclonal antibodies against immunosuppressive proteins of Ascaris suum.

    Science.gov (United States)

    Oshiro, T M; Rafael, A; Enobe, C S; Fernandes, I; Macedo-Soares, M F

    2004-02-01

    The extract of Ascaris suum suppresses the humoral and cellular immune responses to unrelated antigens in the mouse. In order to further characterize the suppressive components of A. suum, we produced specific monoclonal antibodies which can provide an important tool for the identification of these proteins. The A. suum immunosuppressive fractions isolated by gel filtration from an extract of adult worms were used to immunize BALB/c mice. Popliteal lymph node cells taken from the immunized animals were fused with SP2/O myeloma cells and the cloned hybrid cells obtained were screened to determine the specificity of secreted antibodies. Three monoclonal antibodies named MAIP-1, MAIP-2 and MAIP-3 were selected and were shown to react with different epitopes of high molecular weight proteins from the A. suum extract. All antibody molecules have kappa-type light chains but differ in heavy chain isotype. MAIP-1 is a mouse IgM, MAIP-2 is an IgA immunoglobulin and MAIP-3 is an IgG1 immunoglobulin and they recognize the antigen with affinity constants of 1.3 x 10(10) M-1, 7.1 x 10(9) M-1 and 3.8 x 10(7) M-1, respectively. The proteins recognized by these monoclonal antibodies (PAS-1, PAS-2 and PAS-3) were purified from the crude extract by affinity chromatography and injected with ovalbumin in BALB/c mice in order to determine their suppressive activity on heterologous antibody production. It was demonstrated that these three proteins are able to significantly suppress anti-ovalbumin antibody secretion, with PAS-1 being more efficient than the others. PMID:14762577

  11. Comparison of different monoclonal antibodies against immunosuppressive proteins of Ascaris suum

    Directory of Open Access Journals (Sweden)

    T.M. Oshiro

    2004-02-01

    Full Text Available The extract of Ascaris suum suppresses the humoral and cellular immune responses to unrelated antigens in the mouse. In order to further characterize the suppressive components of A. suum, we produced specific monoclonal antibodies which can provide an important tool for the identification of these proteins. The A. suum immunosuppressive fractions isolated by gel filtration from an extract of adult worms were used to immunize BALB/c mice. Popliteal lymph node cells taken from the immunized animals were fused with SP2/O myeloma cells and the cloned hybrid cells obtained were screened to determine the specificity of secreted antibodies. Three monoclonal antibodies named MAIP-1, MAIP-2 and MAIP-3 were selected and were shown to react with different epitopes of high molecular weight proteins from the A. suum extract. All antibody molecules have kappa-type light chains but differ in heavy chain isotype. MAIP-1 is a mouse IgM, MAIP-2 is an IgA immunoglobulin and MAIP-3 is an IgG1 immunoglobulin and they recognize the antigen with affinity constants of 1.3 x 10(10 M-1, 7.1 x 10(9 M-1 and 3.8 x 10(7 M-1, respectively. The proteins recognized by these monoclonal antibodies (PAS-1, PAS-2 and PAS-3 were purified from the crude extract by affinity chromatography and injected with ovalbumin in BALB/c mice in order to determine their suppressive activity on heterologous antibody production. It was demonstrated that these three proteins are able to significantly suppress anti-ovalbumin antibody secretion, with PAS-1 being more efficient than the others.

  12. 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 BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSION: 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.

  13. Progress in the development of therapeutic antibodies targeting prion proteins and β-amyloid peptides

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Prion diseases and Alzheimer’s disease (AD) are characterized by protein misfolding, and can lead to dementia. However, prion diseases are infectious and transmissible, while AD is not. The similarities and differences between these diseases have led researchers to perform comparative studies. In the last 2 decades, progress has been made in immunotherapy using anti-prion protein and anti-β-amyloid antibodies. In this study, we review new ideas and strategies for therapeutic antibodies targeting prion diseases and AD through conformation dependence.

  14. Preparation and application of SARS-associated coronavirus spike protein antibodies

    International Nuclear Information System (INIS)

    Four hybridoma cell lines secreting monoclonal antibody against SARS-associated coronavirus spike protein were obtained and at same time the polyclonal antibodies were also got by immunizing sheep, goats and rabbits with SARS-associated coronavirus spike protein respectively. Immunoradiometric assay (IRMA) and enzyme-linked immunosorbent assay (ELISA) were established using above Abs for detecting SARS-associated coronavirus, and best assay results were observed when McAb CS4C11 was used as labeled Ab and PcAb (sheep) as capture Ab. (author)

  15. Detection of Antibodies in Blood Plasma Using Bioluminescent Sensor Proteins and a Smartphone.

    Science.gov (United States)

    Arts, Remco; den Hartog, Ilona; Zijlema, Stefan E; Thijssen, Vito; van der Beelen, Stan H E; Merkx, Maarten

    2016-04-19

    Antibody detection is of fundamental importance in many diagnostic and bioanalytical assays, yet current detection techniques tend to be laborious and/or expensive. We present a new sensor platform (LUMABS) based on bioluminescence resonance energy transfer (BRET) that allows detection of antibodies directly in solution using a smartphone as the sole piece of equipment. LUMABS are single-protein sensors that consist of the blue-light emitting luciferase NanoLuc connected via a semiflexible linker to the green fluorescent acceptor protein mNeonGreen, which are kept close together using helper domains. Binding of an antibody to epitope sequences flanking the linker disrupts the interaction between the helper domains, resulting in a large decrease in BRET efficiency. The resulting change in color of the emitted light from green-blue to blue can be detected directly in blood plasma, even at picomolar concentrations of antibody. Moreover, the modular architecture of LUMABS allows changing of target specificity by simple exchange of epitope sequences, as demonstrated here for antibodies against HIV1-p17, hemagglutinin (HA), and dengue virus type I. The combination of sensitive ratiometric bioluminescent detection and the intrinsic modularity of the LUMABS design provides an attractive generic platform for point-of-care antibody detection that avoids the complex liquid handling steps associated with conventional immunoassays. PMID:27018236

  16. Distinct oligoclonal band antibodies in multiple sclerosis recognize ubiquitous self-proteins.

    Science.gov (United States)

    Brändle, Simone M; Obermeier, Birgit; Senel, Makbule; Bruder, Jessica; Mentele, Reinhard; Khademi, Mohsen; Olsson, Tomas; Tumani, Hayrettin; Kristoferitsch, Wolfgang; Lottspeich, Friedrich; Wekerle, Hartmut; Hohlfeld, Reinhard; Dornmair, Klaus

    2016-07-12

    Oligoclonal Ig bands (OCBs) of the cerebrospinal fluid are a hallmark of multiple sclerosis (MS), a disabling inflammatory disease of the central nervous system (CNS). OCBs are locally produced by clonally expanded antigen-experienced B cells and therefore are believed to hold an important clue to the pathogenesis. However, their target antigens have remained unknown, mainly because it was thus far not possible to isolate distinct OCBs against a background of polyclonal antibodies. To overcome this obstacle, we copurified disulfide-linked Ig heavy and light chains from distinct OCBs for concurrent analysis by mass spectrometry and aligned patient-specific peptides to corresponding transcriptome databases. This method revealed the full-length sequences of matching chains from distinct OCBs, allowing for antigen searches using recombinant OCB antibodies. As validation, we demonstrate that an OCB antibody from a patient with an infectious CNS disorder, neuroborreliosis, recognized a Borrelia protein. Next, we produced six recombinant antibodies from four MS patients and identified three different autoantigens. All of them are conformational epitopes of ubiquitous intracellular proteins not specific to brain tissue. Our findings indicate that the B-cell response in MS is heterogeneous and partly directed against intracellular autoantigens released during tissue destruction. In addition to helping elucidate the role of B cells in MS, our approach allows the identification of target antigens of OCB antibodies in other neuroinflammatory diseases and the production of therapeutic antibodies in infectious CNS diseases. PMID:27325759

  17. Evaluation of salivary gland protein 1 antibodies in patients with primary and secondary Sjogren's syndrome.

    Science.gov (United States)

    Shen, Long; Kapsogeorgou, Efstathia K; Yu, Meixing; Suresh, Lakshmanan; Malyavantham, Kishore; Tzioufas, Anthanasios G; Ambrus, Julian L

    2014-11-01

    Sjogren's syndrome (SS) has been associated with the expression of anti-Ro and anti-La antibodies. Anti-salivary gland protein 1 (SP1) antibodies have recently been identified in patients with SS. The current work involved a cross sectional study to determine whether anti-SP1 antibodies were identified in particular subgroups of patients with SS. The results of this study revealed that anti-SP1 antibodies were present in the sera of 52% of SS patients while anti-Ro/anti-La was present in 63% of patients. 19% of patients had anti-SP1 without anti-Ro/anti-La. Patients with SS and lymphoma expressed anti-Ro, anti-La and anti-SP1 together. In SS associated with RA, 50% had antibodies anti-SP1 while 40% had anti-Ro/anti-La. In conclusion, anti-SP1 antibodies are commonly seen in both primary and secondary SS and rarely in normal controls. Future studies are needed to determine the roles and timing of expression of anti-SP1 antibodies in Sjogren's syndrome.

  18. Antibody to eosinophil cationic protein suppresses dextran sulfate sodium-induced colitis in rats

    Institute of Scientific and Technical Information of China (English)

    Kazuko Shichijo; Kazuya Makiyama; Chun-Yang Wen; Mutsumi Matsuu; Toshiyuki Nakayama; Masahiro Nakashima; Makoto Ihara; Ichiro Sekine

    2005-01-01

    AIM: To produce an antibody against rat eosinophil cationic protein (ECP) and to examine the effects of the antibody in rats with dextran sulfate sodium (DSS)-induced colitis.METHODS: An antibody was raised against rat ECP. Rats were treated with 3% DSS in drinking water for 7 d and received the antibody or normal serum. The colons were exarmined histologically and correlated with clinical symptoms.Immunohistochemistry and Western blot analysis were estimated as a grade of inflammation.RESULTS: The ECP antibody stained the activated eosinophils around the injured crypts in the colonic mucosa.Antibody treatment reduced the severity of colonic ulceration and acute clinical symptoms (diarrhea and/or blood-stained stool). Body weight gain was significantly greater and the colon length was significantly longer in anti-ECP-treated rats than in normal serum-treated rats. Expression of ECP in activated eosinophils was associated with the presence of erosions and inflammation. The number of Ki-67-positive cells in the regenerated surface epithelium increased in anti-ECP-treated rats compared with normal serum-treated rats. Western blot analysis revealed reduced expression of macrophage migration inhibitory factor (MIF) in anti-ECP-treated rats.CONCLUSION: Our results indicate that treatment with ECP antibody, improved DSS-induced colitis in rats, possibly by increasing the regenerative activity of the colonic epithelium and downregulation of the immune response,and suggest that anti-ECP may promote intestinal wound healing in patients with ulcerative colitis (UC).

  19. Analysis of Antibodies Directed against Merozoite Surface Protein 1 of the Human Malaria Parasite Plasmodium falciparum

    Science.gov (United States)

    Woehlbier, Ute; Epp, Christian; Kauth, Christian W.; Lutz, Rolf; Long, Carole A.; Coulibaly, Boubacar; Kouyaté, Bocar; Arevalo-Herrera, Myriam; Herrera, Sócrates; Bujard, Hermann

    2006-01-01

    The 190-kDa merozoite surface protein 1 (MSP-1) of Plasmodium falciparum, an essential component in the parasite's life cycle, is a primary candidate for a malaria vaccine. Rabbit antibodies elicited by the heterologously produced MSP-1 processing products p83, p30, p38, and p42, derived from strain 3D7, were analyzed for the potential to inhibit in vitro erythrocyte invasion by the parasite and parasite growth. Our data show that (i) epitopes recognized by antibodies, which inhibit parasite replication, are distributed throughout the entire MSP-1 molecule; (ii) when combined, antibodies specific for different regions of MSP-1 inhibit in a strictly additive manner; (iii) anti-MSP-1 antibodies interfere with erythrocyte invasion as well as with the intraerythrocytic growth of the parasite; and (iv) antibodies raised against MSP-1 of strain 3D7 strongly cross-inhibit replication of the heterologous strain FCB-1. Accordingly, anti-MSP-1 antibodies appear to be capable of interfering with parasite multiplication at more than one level. Since the overall immunogenicity profile of MSP-1 in rabbits closely resembles that found in sera of Aotus monkeys immunized with parasite-derived MSP-1 and of humans semi-immune to malaria from whom highly inhibiting antigen-specific antibodies were recovered, we consider the findings reported here to be relevant for the development of MSP-1-based vaccines against malaria. PMID:16428781

  20. Analysis of antibodies directed against merozoite surface protein 1 of the human malaria parasite Plasmodium falciparum.

    Science.gov (United States)

    Woehlbier, Ute; Epp, Christian; Kauth, Christian W; Lutz, Rolf; Long, Carole A; Coulibaly, Boubacar; Kouyaté, Bocar; Arevalo-Herrera, Myriam; Herrera, Sócrates; Bujard, Hermann

    2006-02-01

    The 190-kDa merozoite surface protein 1 (MSP-1) of Plasmodium falciparum, an essential component in the parasite's life cycle, is a primary candidate for a malaria vaccine. Rabbit antibodies elicited by the heterologously produced MSP-1 processing products p83, p30, p38, and p42, derived from strain 3D7, were analyzed for the potential to inhibit in vitro erythrocyte invasion by the parasite and parasite growth. Our data show that (i) epitopes recognized by antibodies, which inhibit parasite replication, are distributed throughout the entire MSP-1 molecule; (ii) when combined, antibodies specific for different regions of MSP-1 inhibit in a strictly additive manner; (iii) anti-MSP-1 antibodies interfere with erythrocyte invasion as well as with the intraerythrocytic growth of the parasite; and (iv) antibodies raised against MSP-1 of strain 3D7 strongly cross-inhibit replication of the heterologous strain FCB-1. Accordingly, anti-MSP-1 antibodies appear to be capable of interfering with parasite multiplication at more than one level. Since the overall immunogenicity profile of MSP-1 in rabbits closely resembles that found in sera of Aotus monkeys immunized with parasite-derived MSP-1 and of humans semi-immune to malaria from whom highly inhibiting antigen-specific antibodies were recovered, we consider the findings reported here to be relevant for the development of MSP-1-based vaccines against malaria.

  1. Identification of five serum protein markers for detection of ovarian cancer by antibody arrays.

    Directory of Open Access Journals (Sweden)

    Weidong Jiang

    Full Text Available BACKGROUND: Protein and antibody arrays have emerged as a promising technology to study protein expression and protein function in a high-throughput manner. These arrays also represent a new opportunity to profile protein expression levels in cancer patients' samples and to identify useful biosignatures for clinical diagnosis, disease classification, prediction, drug development and patient care. We applied antibody arrays to discover a panel of proteins which may serve as biomarkers to distinguish between patients with ovarian cancer and normal controls. METHODOLOGY/PRINCIPAL FINDINGS: Using a case-control study design of 34 ovarian cancer patients and 53 age-matched healthy controls, we profiled the expression levels of 174 proteins using antibody array technology and determined the CA125 level using ELISA. The expression levels of those proteins were analyzed using 3 discriminant methods, including artificial neural network, classification tree and split-point score analysis. A panel of 5 serum protein markers (MSP-alpha, TIMP-4, PDGF-R alpha, and OPG and CA125 was identified, which could effectively detect ovarian cancer with high specificity (95% and high sensitivity (100%, with AUC =0.98, while CA125 alone had an AUC of 0.87. CONCLUSIONS/SIGNIFICANCE: Our pilot study has shown the promising set of 5 serum markers for ovarian cancer detection.

  2. Synthesis and Characterization of Hapten-Protein Conjugates for Antibody Production against Cyanogenic Glycosides.

    Science.gov (United States)

    Bolarinwa, Islamiyat Folashade

    2015-07-01

    Consumption of cyanogenic plants can cause serious health problems for humans. The ability to detect and quantify cyanogenic glycosides, capable of generating cyanide, could contribute to prevention of cyanide poisoning from the consumption of improperly processed cyanogenic plants. Hapten-protein conjugates were synthesized with amygdalin and linamarin by using a novel approach. Polyclonal antibodies were generated by immunizing four New Zealand White rabbits with synthesized amygdalin-bovine serum albumin and linamarin-bovine serum albumin immunogen. This is the first time an antibody was produced against linamarin. Antibody titer curves were obtained from all the four rabbits by using a noncompetitive enzyme-linked immunosorbent assay. High antibody titer was obtained at dilutions greater than 1:50,000 from both immunogens. This new method is an important step forward in preventing ingestion of toxic cyanogenic glycosides. PMID:26197297

  3. Effect of increased CRM₁₉₇ carrier protein dose on meningococcal C bactericidal antibody response.

    Science.gov (United States)

    Lee, Lucia H; Blake, Milan S

    2012-04-01

    New multivalent CRM(197)-based conjugate vaccines are available for childhood immunization. Clinical studies were reviewed to assess meningococcal group C (MenC) antibody responses following MenC-CRM(197) coadministration with CRM(197)-based pneumococcal or Haemophilus influenzae type b conjugate vaccines. Infants receiving a total CRM(197) carrier protein dose of ∼50 μg and concomitant diphtheria-tetanus-acellular pertussis (DTaP)-containing vaccine tended to have lower MenC geometric mean antibody titers and continued to have low titers after the toddler dose. Nevertheless, at least 95% of children in the reported studies achieved a MenC serum bactericidal antibody (SBA) titer of ≥ 1:8 after the last infant or toddler dose. SBA was measured using an assay with a baby rabbit or human complement source. Additional studies are needed to assess long-term antibody persistence and MenC CRM(197) conjugate vaccine immunogenicity using alternative dosing schedules.

  4. Serum antibody immunoreactivity to equine zona protein after SpayVac vaccination.

    Science.gov (United States)

    Mask, Tracy A; Schoenecker, Kathryn A; Kane, Albert J; Ransom, Jason I; Bruemmer, Jason E

    2015-07-15

    Immunocontraception with porcine ZP (pZP) can be an effective means of fertility control in feral horses. Previous studies suggest that antibodies produced after pZP vaccination may both inhibit fertilization and cause follicular dysgenesis. Zonastat-H, PZP-22, and SpayVac are three pZP vaccines proposed for use in horses. Although all these vaccines contain the pZP antigen, variations in antigen preparation and vaccine formulation lead to differences in antigenic properties among them. Likewise, despite numerous efficacy and safety studies of Zonastat-H and PZP-22, the contraceptive mechanisms of SpayVac remain unclear. The preparation of pZP for SpayVac is thought to include more nonzona proteins, making it less pure than the other two vaccines. This may result in increased antigenicity of the vaccine. We therefore investigated the immunoreactivity of serum antibodies from SpayVac-vaccinated mares to equine zona protein. Western blot analyses revealed an immunoreactivity of these antibodies to protein isolated from mature equine oocytes, ZP, follicular tissues, and ovarian tissues. Immunohistochemical analyses were used to locate the binding of serum antibodies to the ZP of immature oocytes in ovarian stromal tissue. We also found serum antibodies from SpayVac-treated mares to be predominantly specific for zona protein 3. Collectively, our results suggest a model where serum antibodies produced in response to SpayVac vaccination are immunoreactive to equine zona protein in vitro. Our study lends insight into the contraceptive mechanisms underlying the infertility observed after SpayVac vaccination.

  5. Production and purification of avian antibodies (igys) from inclusion bodies of a recombinant protein central in nad+ metabolism

    OpenAIRE

    Moreno-González, Paula A.; Diaz, Gonzalo J.; María H. Ramírez-Hernández

    2013-01-01

    The use of hens for the production of polyclonal antibodies reduces animal intervention and moreover yields a higher quantity of antibodies than other animal models.  The phylogenetic distance between bird and mammal antigens, often leads to more specific avian antibodies than their mammalian counterparts.Since a large amount of antigen is required for avian antibody production, the use of recombinant proteins for this procedure has been growing faster over the last years. Nevertheless, recom...

  6. A Halotyrosine Antibody that Detects Increased Protein Modifications in Asthma Patients

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hongjun; Hallstrand, Teal S.; Daly, Don S.; Matzke, Melissa M.; Nair, Parameswaran; Bigelow, Diana J.; Pounds, Joel G.; Zangar, Richard C.

    2014-01-31

    Background-Airway inflammation plays an important pathophysiological role in asthma. Eosinophils produce hypobromite and bromotyrosine while neutrophils produce hypochlorite and chlorotyrosine. Objective-To evaluate halotyrosine modifications of individual airway proteins as a marker of inflammation in asthma using an antibody-based assay. Methods-We developed a novel monoclonal antibody (BTK-94C) that binds halogenated tyrosine residues, and used this antibody in a custom enzyme-linked immunosorbent assay (ELISA) microarray platform to examine halotyrosine levels in 23 proteins in three independent sets of sputum samples (52 samples total). Results-In 15 subjects with either no asthma, or with asthma characterized by high or low sputum eosinophil counts, we found associations between increased halotyrosine levels of at least three proteins and severity of airway hyperresponsiveness (AHR). Treatment with mepolizumab in 17 patients with sputum eosinophilia markedly reduced the sputum eosinophilia and significantly reduced halotyrosine levels in one sputum protein. Further analysis of 10 subjects with neutrophilic asthma and 10 health controls demonstrated a broad increase in halotyrosine in the patients with airway neutrophilia. Conclusions-Significantly higher levels of halotyrosine are associated with asthma in the asthma phenotypes we examined. The halotyrosine levels correlated with indirect AHR in the form of exercise-induced bronchoconstriction. Clinical Implication-An antibody-based assay for tyrosine halogenation in specific proteins may prove useful for assessing airway inflammation in asthma. Capsule Summary-An antibody to measure protein monobrominated tyrosine and other halotyrosine modifications was developed and used to evaluate halogenation in specific proteins in the airways for the first time. Associations were found between levels of halotyrosine and exercise-induced bronchoconstriction, and eosinophil and neutrophil inflammation in sputum from

  7. Protection against dengue virus infection in mice by administration of antibodies against modified nonstructural protein 1.

    Directory of Open Access Journals (Sweden)

    Shu-Wen Wan

    Full Text Available BACKGROUND: Infection with dengue virus (DENV may cause life-threatening disease with thrombocytopenia and vascular leakage which are related to dysfunction of platelets and endothelial cells. We previously showed that antibodies (Abs against DENV nonstructural protein 1 (NS1 cross-react with human platelets and endothelial cells, leading to functional disturbances. Based on sequence homology analysis, the C-terminal region of DENV NS1 protein contains cross-reactive epitopes. For safety in vaccine development, the cross-reactive epitopes of DENV NS1 protein should be deleted or modified. METHODOLOGY/PRINCIPAL FINDINGS: We tested the protective effects of Abs against full-length DENV NS1, NS1 lacking the C-terminal amino acids (a.a. 271-352 (designated ΔC NS1, and chimeric DJ NS1 consisting of N-terminal DENV NS1 (a.a. 1-270 and C-terminal Japanese encephalitis virus NS1 (a.a. 271-352. The anti-ΔC NS1 and anti-DJ NS1 Abs showed a lower binding activity to endothelial cells and platelets than that of anti-DENV NS1 Abs. Passive immunization with anti-ΔC NS1 and anti-DJ NS1 Abs reduced DENV-induced prolonged mouse tail bleeding time. Treatment with anti-DENV NS1, anti-ΔC NS1 and anti-DJ NS1 Abs reduced local skin hemorrhage, controlled the viral load of DENV infection in vivo, synergized with complement to inhibit viral replication in vitro, as well as abolished DENV-induced macrophage infiltration to the site of skin inoculation. Moreover, active immunization with modified NS1 protein, but not with unmodified DENV NS1 protein, reduced DENV-induced prolonged bleeding time, local skin hemorrhage, and viral load. CONCLUSIONS/SIGNIFICANCE: These results support the idea that modified NS1 proteins may represent an improved strategy for safe and effective vaccine development against DENV infection.

  8. Cytokines: muscle protein and amino acid metabolism

    DEFF Research Database (Denmark)

    van Hall, Gerrit

    2012-01-01

    of IL-6 on the regulation of muscle protein metabolism but indirectly via IL-6 reducing amino acid availability. SUMMARY: Recent studies suggest that the best described cytokines TNF-α and IL-6 are unlikely to be the major direct mediators of muscle protein loss in inflammatory diseases. However....... However, this does not seem applicable for inflammatory diseases or human models of sepsis, in which the enhanced imbalance between these two processes is observed within an enhanced, normal or reduced muscle protein turnover.......PURPOSE OF REVIEW: This review highlights the role of cytokines, in particular tumour necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), in relation to the nature of human in-vivo muscle wasting in disease. RECENT FINDINGS: Infusion of human TNF-α and IL-6 in healthy individuals, acutely...

  9. PRODUCTION AND CHARACTERIZATION OF MONOCLONAL AND POLYCLONAL ANTIBODY AGAINST RECOMBINANT OUTER MEMBRANE PROTEIN

    Directory of Open Access Journals (Sweden)

    Mahdi Fasihi-Ramandi

    2014-01-01

    Full Text Available There are many studies related to immunological and molecular methods for diagnosis of Vibrio cholera (V. cholerae. However, most assays dependent on enrichment of culture of bacteria, which need more time and involves the use of costly equipment and reagents. In this study Balb/c mice were immunized with recombinant Outer Membrane Protein (rOMPw of vibrio cholerae and splenocytes of hyper immunized mice were fused with murine myeloma Sp2/0 cells. Positive hybridomas were selected by ELISA using rOMPw as coating antigen. The monoclonal antibodies from ascitic fluids were purified and its reaction with rOMPw was assessed by ELISA. Polyclonal antibodies were also produced by immunization of rabbits with the above mentioned antigen. The rabbit sera was affinity purified using Hi-Trap protein G column. The result showed that monoclonal antibody specific to rOMPw has been successfully generated. The monoclonal antibody reacted with recombinant OMPw in ELISA and immunonoblat method. Rabbit polyclonal antibody was also bound to rOMPw by ELISA. The results of agglutination test with whole bacteria also showed that both mouse monoclonal and rabbit polyclonal antibodies reacted with whole vibrio cholera but not other related bacteria. The purpose of this study was to check out if anti OMPw antibodies could use as diagnostic assay for detection of V. cholerae. Our results demonstrated that anti recombinant OMPw monoclonal and polyclonal antibodies are able to diagnose whole bacteria in pure culture using agglutination test but not by home made immunochromatic strip test.

  10. A Lateral Flow Protein Microarray for Rapid and Sensitive Antibody Assays

    Directory of Open Access Journals (Sweden)

    Helene Andersson-Svahn

    2011-11-01

    Full Text Available Protein microarrays are useful tools for highly multiplexed determination of presence or levels of clinically relevant biomarkers in human tissues and biofluids. However, such tools have thus far been restricted to laboratory environments. Here, we present a novel 384-plexed easy to use lateral flow protein microarray device capable of sensitive (< 30 ng/mL determination of antigen-specific antibodies in ten minutes of total assay time. Results were developed with gold nanobeads and could be recorded by a cell-phone camera or table top scanner. Excellent accuracy with an area under curve (AUC of 98% was achieved in comparison with an established glass microarray assay for 26 antigen-specific antibodies. We propose that the presented framework could find use in convenient and cost-efficient quality control of antibody production, as well as in providing a platform for multiplexed affinity-based assays in low-resource or mobile settings.

  11. Immunotherapy-responsive limbic encephalitis with antibodies to glutamic acid decarboxylase.

    Science.gov (United States)

    Markakis, Ioannis; Alexopoulos, Harry; Poulopoulou, Cornelia; Akrivou, Sofia; Papathanasiou, Athanasios; Katsiva, Vassiliki; Lyrakos, Georgios; Gekas, Georgios; Dalakas, Marinos C

    2014-08-15

    Glutamic acid decarboxylase (GAD) has been recently identified as a target of humoral autoimmunity in a small subgroup of patients with non-paraneoplastic limbic encephalitis (NPLE). We present a patient with NPLE and positive anti-GAD antibodies who showed significant improvement after long-term immunotherapy. A 48-year old female was admitted with a two-year history of anterograde amnesia and seizures. Brain MRI revealed bilateral lesions of medial temporal lobes. Screening for anti-neuronal antibodies showed high anti-GAD titers in both serum and cerebrospinal fluid (CSF) with strong evidence of intrathecal production. The patient received treatment with prednisolone and long-term plasma exchange. During a 12-month follow-up, she exhibited complete seizure remission and an improvement in memory and visuo-spatial skills. Anti-GAD antibodies may serve as a useful marker to identify a subset of NPLE patients that respond to immunoregulatory treatment.

  12. Association of antibodies to Plasmodium falciparum Reticulocyte Binding Protein Homologue 5 with protection from clinical malaria

    Directory of Open Access Journals (Sweden)

    Chris Y. H. Chiu

    2014-06-01

    Full Text Available Emerging evidence suggests that antibodies against merozoite proteins involved in P. falciparum invasion into the red blood cell (RBC play an important role in clinical immunity to malaria. The protein family of parasite antigens known as P. falciparum Reticulocyte Binding Protein Homologue (PfRh is required for RBC invasion. PfRh5 is the only member within the PfRh family that cannot be genetically deleted, suggesting it plays an essential role in parasite survival. This antigen forms a complex with the cysteine-rich P. falciparum Rh5 interacting protein (PfRipr, on the merozoite surface during RBC invasion. The PfRh5 ectodomain sequence and a C-terminal fragment of PfRipr were cloned and expressed in E. coli and baculovirus-infected cells respectively. Immunization of rabbits with these recombinant proteins induced antibodies able to inhibit growth of various P. falciparum strains. Antibody responses to these proteins were investigated in a treatment-re-infection study conducted in an endemic area of Papua New Guinea (PNG to determine their contribution to naturally acquired immunity. Antibody titres to PfRh5 but not PfRipr showed strong association with protection against P. falciparum clinical episodes. When associations with time to first infection were analysed, high antibody levels against PfRh5 were also found to be associated with protection from high-density infections but not from re-infection. Together these results indicate that PfRh5 is an important target of protective immunity and constitutes a promising vaccine candidate.

  13. Combining phage display with de novo protein sequencing for reverse engineering of monoclonal antibodies.

    Science.gov (United States)

    Rickert, Keith W; Grinberg, Luba; Woods, Robert M; Wilson, Susan; Bowen, Michael A; Baca, Manuel

    2016-01-01

    The enormous diversity created by gene recombination and somatic hypermutation makes de novo protein sequencing of monoclonal antibodies a uniquely challenging problem. Modern mass spectrometry-based sequencing will rarely, if ever, provide a single unambiguous sequence for the variable domains. A more likely outcome is computation of an ensemble of highly similar sequences that can satisfy the experimental data. This outcome can result in the need for empirical testing of many candidate sequences, sometimes iteratively, to identity one which can replicate the activity of the parental antibody. Here we describe an improved approach to antibody protein sequencing by using phage display technology to generate a combinatorial library of sequences that satisfy the mass spectrometry data, and selecting for functional candidates that bind antigen. This approach was used to reverse engineer 2 commercially-obtained monoclonal antibodies against murine CD137. Proteomic data enabled us to assign the majority of the variable domain sequences, with the exception of 3-5% of the sequence located within or adjacent to complementarity-determining regions. To efficiently resolve the sequence in these regions, small phage-displayed libraries were generated and subjected to antigen binding selection. Following enrichment of antigen-binding clones, 2 clones were selected for each antibody and recombinantly expressed as antigen-binding fragments (Fabs). In both cases, the reverse-engineered Fabs exhibited identical antigen binding affinity, within error, as Fabs produced from the commercial IgGs. This combination of proteomic and protein engineering techniques provides a useful approach to simplifying the technically challenging process of reverse engineering monoclonal antibodies from protein material.

  14. Protein A Detection Based on Quantum Dots-Antibody Bioprobe Using Fluorescence Coupled Capillary Electrophoresis

    Directory of Open Access Journals (Sweden)

    Lin Qiu

    2014-01-01

    Full Text Available In this report, fluorescence detection coupled capillary electrophoresis (CE-FL was used to detect Protein A. Antibody was first labeled with Cy5 and then mixed with quantum dots (QDs to form QDs-antibody bioprobe. Further, we observed fluorescence resonance energy transfer (FRET from QDs donor to Cy5 acceptor. The bioprobe was formed and brought QDs and Cy5 close enough to allow FRET to occur. After adding protein A, the FRET system was broken and caused the FRET signal to decrease. Thus, a new method for the determination of protein A was proposed based on the FRET signal changes. This study provides a new trail of thought for the detection of protein.

  15. Development and Characterization of Monoclonal Antibodies Against Human Heart Type Fatty Acid Binding Protein and Its Application in Lateral Flow Immunoassay%抗心型脂肪酸结合蛋白单克隆抗体制备、鉴定和在侧向免疫层析方法中的应用

    Institute of Scientific and Technical Information of China (English)

    康可人; 吴培钿; 李悦琳; 黄绮玲; 李高辉; 唐时幸; 王继华

    2013-01-01

    目的:制备抗心型脂肪酸结合蛋白(H-FABP)单克隆抗体(mAb),并建立侧向免疫层析方法检测血浆中H-FABP.方法:用H-FABP蛋白免疫纯系Balb/c小鼠,采用杂交瘤技术建立能稳定分泌抗人H-FABP的单克隆杂交瘤细胞株.常规制备腹水,纯化后得到特异性抗H-FABP单克隆抗体,进行效价、特异性、亲和力的鉴定分析,并在ELISA平台进行抗体配对,用所筛选到的抗体对初步建立了检测H-FABP的侧向免疫层析方法.结果:成功获得12株稳定分泌抗体的阳性细胞株,并筛选出能相互配对,并应用于侧向免疫层析平台的抗体3D1和5F4,检测临床样品与对照试剂比较总符合率为100%.结论:筛选能稳定分泌抗体的细胞株,配对抗体应用于侧向免疫层析检测方法中,能快速、特异、灵敏的检测出临床样品中H-FABP,为临床应用快速检测H-FABP指标提供了方法和关键材料.%AIM; To develop and characterize monoclonal antibodies ( mAb) against human heart type fatty acid binding protein (H-FABP) ; To develop a rapid lateral flow immunoassay for detecting H-FABP in plasma using the identified mAbs. Methods; BALB/c mice were immunized with H-FABP. The hybridoma cells were generated by fusing spleen cells and myeloma cells SP2/0 followed by screening and clonally selecting. The mAbs were purified from ascites and characterized by indirect ELISA and Western Blot, and were used for developing a rapid lateral flow immunoassay. Results; Twelve hybridoma cell lines were found to secret anti-H-FABP with high titers, specificity and affinity. Among them, the antibody pair of 3D1 and 5F4 were used as conjugate and coating antibody, respectively, in lateral flow immunoassay. The newly developed assay was used to detect 203 patients plasma. A 100% consistence was observed when compared with the reference kit. Conclusion; Two mAbs against H-FABP with high titers, specificity and affinity were obtained. The rapid lateral flow

  16. Erratum: Colorectal Cancer Cell Surface Protein Profiling Using an Antibody Microarray and Fluorescence Multiplexing.

    Science.gov (United States)

    2015-01-01

    The author's email has been corrected in the publication of Colorectal Cancer Cell Surface Protein Profiling Using an Antibody Microarray and Fluorescence Multiplexing. There was an error with the author, Jerry Zhou's, email. The author's email has been updated to: j.zhou@uws.edu.au from: jzho7551@mail.usyd.edu.au. PMID:26167960

  17. Polyclonal antibody production and expression of CREG protein in human vascular smooth muscle cells

    Institute of Scientific and Technical Information of China (English)

    Yaling HAN; Haiwei LIU; Jian KANG; Xiaozeng WANG; Ye HU; Lianyou ZHAO; Shaohua LI

    2005-01-01

    Objectives The cellular repressor of E1A-activated genes (CREG), a novel gene, was recently found to play a role in inhibiting cell growth and promoting cell differentiation. The purpose of this study was to obtain antibody against CREG protein and to study the expression of CREG protein in human internal thoracic artery cells (HITASY) which express different patterns of differentiation markers after serum withdrawal. Methods The open reading frame of CREG gene sequence was amplified by PCR and cloned into the pGEX-4T-1 vector. Glutathione-S-transferase (GST)-CREG fusion protein was expressed in E. Coli BL21 and purified from inclusion bodies by Sephacryl S-200 chromatography. Rabbits were immunized with the purified GST-CREG protein. Western blot examined with immunohistochemistry staining and the protein expression level was analyzed by Western blot in HITASY cells after serum removal. Results It was confirmed by using endonuclease digesting and DNA sequencing that the PCR product of CREG was correctly inserted into the vector. The GST-CREG protein was purified with gel filtration chromatography. Polyclonal antibody against GST-CREG was obtained from rabbits. CREG protein immunohistochemistry staining displayed a perinuclear distribution in the cytoplasm of HITASY cells. Results from Western blot suggested that comparing with the untreated cells upregulation of CREG polyclonal antibody against CREG was comfirmed. Using this antibody, the changes of CREG protein expression was observed in the process of phenotypic modulation of HITASY cells. These results provide basic understanding on the relationship of CREG gene with the cell phenotypic conversion.

  18. Discrete nuclear structures in actively growing neuroblastoma cells are revealed by antibodies raised against phosphorylated neurofilament proteins

    Directory of Open Access Journals (Sweden)

    Raabe Timothy D

    2003-04-01

    Full Text Available Abstract Background Nuclear objects that have in common the property of being recognized by monoclonal antibodies specific for phosphoprotein epitopes and cytoplasmic intermediate filaments (in particular, SMI-31 and RT-97 have been reported in glial and neuronal cells, in situ and in vitro. Since neurofilament and glial filaments are generally considered to be restricted to the cytoplasm, we were interested in exploring the identity of the structures labeled in the nucleus as well as the conditions under which they could be found there. Results Using confocal microscopy and western analysis techniques, we determined 1 the immunolabeled structures are truly within the nucleus; 2 the phosphoepitope labeled by SMI-31 and RT-97 is not specific to neurofilaments (NFs and it can be identified on other intermediate filament proteins (IFs in other cell types; and 3 there is a close relationship between DNA synthesis and the amount of nuclear staining by these antibodies thought to be specific for cytoplasmic proteins. Searches of protein data bases for putative phosphorylation motifs revealed that lamins, NF-H, and GFAP each contain a single tyrosine phosphorylation motif with nearly identical amino acid sequence. Conclusion We therefore suggest that this sequence may be the epitope recognized by SMI-31 and RT-97 mABs, and that the nuclear structures previously reported and shown here are likely phosphorylated lamin intermediate filaments, while the cytoplasmic labeling revealed by the same mABs indicates phosphorylated NFs in neurons or GFAP in glia.

  19. Antibody to collapsin response mediator protein 1 promotes neurite outgrowth from rat hippocampal neurons

    Institute of Scientific and Technical Information of China (English)

    Hongsheng Lin; Jing Chen; Wenbin Zhang; Xiaobing Gong; Biao Chen; Guoqing Guo

    2011-01-01

    This study examined the role of collapsin response mediator protein 1 (CRMP-1) on neurite outgrowth from rat hippocampal neurons by blocking its function using an antibody. Hippocampal neurons, cultured in vitro, were treated (blocked) using a polyclonal antibody to CRMP-1, and neurite outgrowth and cytoskeletal changes w ere captured using atomic force microscopy and laser confocal microscopy. Control cells, treated with normal rabbit IgG, established their characteristic morphology and had a large number of processes emerging from the soma, including numerous branches. Microtubules were clearly visible in the soma, formed an elaborate network, and were aligned in parallel arrays to form bundles which projected into neurites. After blocking with CRMP-1 antibody, the number of branches emerging from axons and dendrites significantly increased and were substantially longer, compared with control cells. However, the microtubule network nearly disappeared and only a few remnants were visible. When CRMP-1 antibody-blocked neurons were treated with the Rho inhibitor, Y27632, numerous neurites emerged from the soma, and branches were more abundant than in control neurons. Although the microtubules were not as clearly visible compared with neurons cultured in control medium, the microtubule network recovered in cells treated with Y27632, when compared with cells that were blocked by CRMP-1 antibody (but not treated with Y27632). These results demonstrate that neurite outgrowth from hippocampal neurons can be promoted by blocking CRMP-1 with a polyclonal antibody.

  20. Antibody microarray analyses of signal transduction protein expression and phosphorylation during porcine oocyte maturation.

    Science.gov (United States)

    Pelech, Steven; Jelinkova, Lucie; Susor, Andrej; Zhang, Hong; Shi, Xiaoqing; Pavlok, Antonin; Kubelka, Michal; Kovarova, Hana

    2008-07-01

    Kinex antibody microarray analyses was used to investigate the regulation of 188 protein kinases, 24 protein phosphatases, and 170 other regulatory proteins during meiotic maturation of immature germinal vesicle (GV+) pig oocytes to maturing oocytes that had completed meiosis I (MI), and fully mature oocytes arrested at metaphase of meiosis II (MII). Increases in apparent protein levels of protein kinases accounted for most of the detected changes during the GV to MI transition, whereas reduced protein kinase levels and increased protein phosphorylation characterized the MI to MII transition. During the MI to MII period, many of the MI-associated increased levels of the proteins and phosphosites were completely or partially reversed. The regulation of these proteins were also examined in parallel during the meiotic maturation of bovine, frog, and sea star oocytes with the Kinex antibody microarray. Western blotting analyses confirmed altered expression levels of Bub1A, IRAK4, MST2, PP4C, and Rsk2, and the phosphorylation site changes in the kinases Erk5 (T218 + Y220), FAK (S722), GSK3-beta (Y216), MEK1 (S217 + S221) and PKR1 (T451), and nucleophosmin/B23 (S4) during pig oocyte maturation.

  1. Anti-peptide aptamers recognize amino acid sequence and bind a protein epitope.

    OpenAIRE

    Xu, W; Ellington, A. D.

    1996-01-01

    In vitro selection of nucleic acid binding species (aptamers) is superficially similar to the immune response. Both processes produce biopolymers that can recognize targets with high affinity and specificity. While antibodies are known to recognize the sequence and conformation of protein surface features (epitopes), very little is known about the precise interactions between aptamers and their epitopes. Therefore, aptamers that could recognize a particular epitope, a peptide fragment of huma...

  2. Production and purification of avian antibodies (IgYs from inclusion bodies of a recombinant protein central in NAD+ metabolism

    Directory of Open Access Journals (Sweden)

    Paula A. Moreno-González

    2013-08-01

    Full Text Available The use of hens for the production of polyclonal antibodies reduces animal intervention and moreover yields a higher quantity of antibodies than other animal models.  The phylogenetic distance between bird and mammal antigens, often leads to more specific avian antibodies than their mammalian counterparts.Since a large amount of antigen is required for avian antibody production, the use of recombinant proteins for this procedure has been growing faster over the last years. Nevertheless, recombinant protein production through heterologous systems frequently prompts the protein to precipitate, forming insoluble aggregates of limited utility (inclusion bodies. A methodology for the production of avian polyclonal antibodies, using recombinant protein from inclusion bodies is presented in this article.In order to produce the antigen, a recombinant Nicotinamide mononucleotide adenylyltransferase from Giardia intestinalis (His-GiNMNAT was expressed in Escherichia coli.  The protein was purified through solubilization from inclusion bodies prior to its renaturalization.  Antibodies were purified from egg yolk of immunized hens by water dilution, followed by ammonium sulfate precipitation and thiophilic affinity chromatography.The purified antibodies were tested against His-GiNMNAT protein in Western blot essays. From one egg yolk, 14.4 mg of highly pure IgY were obtained; this antibody was able to detect 15ng of His-GiNMNAT.  IgY specificity was improved by means of antigen affinity purification, allowing its use for parasite protein recognition.

  3. Species-Specific Antibody Responses to the Recombinant 53-Kilodalton Excretory and Secretory Proteins in Mice Infected with Trichinella spp.▿

    OpenAIRE

    Nagano, Isao; Wu, Zhiliang; Takahashi, Yuzo

    2008-01-01

    The 53-kDa proteins in larval excretory and secretory (E-S) products were expressed from five Trichinella species (T. spiralis, T. britovi, T. nativa, T. pseudospiralis, and T. papuae), using the Escherichia coli expression system, and the antibody responses to the 53-kDa recombinant proteins in mice infected with Trichinella spp. were analyzed by Western blotting. The 53-kDa protein is conserved among the five Trichinella species, with >60% similarity in amino acid sequences. The 53-kDa reco...

  4. Monoclonal antibodies targeted to alpha-oligonucleotides. Characterisation and application in nucleic acid detection.

    OpenAIRE

    Cros, P.; Kurfürst, R; Allibert, P; Battail, N; Piga, N; Roig, V; Thuong, N T; Mandrand, B; Hélène, C

    1994-01-01

    The aim of the present study was to test the antigenicity of alpha-deoxyribonucleotides in order to develop a new tool for the detection of nucleic acid sequences for use in diagnostic applications. We describe four monoclonal antibodies (Mabs) which recognize alpha-deoxyribonucleotides. Two were raised against a poly(alpha-dT) sequence and specifically recognized the alpha-dT nucleotide. Two were raised against a sequence containing all four common nucleotides as alpha-nucleotides and, surpr...

  5. Identification of a novel canine distemper virus B-cell epitope using a monoclonal antibody against nucleocapsid protein.

    Science.gov (United States)

    Yi, Li; Cheng, Yuening; Zhang, Miao; Cao, Zhigang; Tong, Mingwei; Wang, Jianke; Zhao, Hang; Lin, Peng; Cheng, Shipeng

    2016-02-01

    Canine distemper virus (CDV) is a member of the genus Morbillivirus within the family Paramyxoviridae and has caused severe economic losses in China. Nucleocapsid protein (N) is the major structural viral protein and can be used to diagnose CDV and other morbilliviruses. In this study, a specific monoclonal antibody, 1N8, was produced against the CDV N protein (amino acids 277-471). A linear N protein epitope was identified by subjecting a series of partially overlapping synthesized peptides to enzyme-linked immunosorbent assay (ELISA) analysis. The results indicated that (350)LNFGRSYFDPA(360) was the minimal linear epitope that could be recognized by mAb 1N8. ELISA assays revealed that mouse anti-CDV sera could also recognize the minimal linear epitope. Alignment analysis of the amino acid sequences indicated that the epitope was highly conserved among CDV strains. Furthermore, the epitope was conserved among other morbilliviruses, which was confirmed with PRRV using western blotting. Taken together, the results of this study may have potential applications in the development of suitable diagnostic techniques for CDV or other morbilliviruses. PMID:26514066

  6. Cervical Antibodies to Herpes Simplex Virus Proteins in Pregnancy and Puerperium: A Pilot Study

    OpenAIRE

    D. Heather Watts; Jeanne-Marie Guise; Zane Brown; Lawrence Corey; Ashley, Rhoda L.

    1996-01-01

    Objective: This study was undertaken to evaluate the changes in total and anti-herpes simplex virus (HSV)-specific cervical IgA and IgG antibody profiles during and after pregnancy. Methods: Serum and cervical secretions were obtained from pregnant patients before 20 weeks gestation, at 34–36 weeks gestation, and at 6 weeks postpartum and tested for total IgA and IgG antibody and for IgA and IgG to HSV proteins by Western blot. Results: Seven women were HSV seronegative, 14 HSV-1 seropositive...

  7. Monoclonal antibodies against a synthetic peptide from human immunodeficiency virus type 1 Nef protein

    DEFF Research Database (Denmark)

    Steinaa, L; Wulff, A M; Saermark, T

    1994-01-01

    Monoclonal antibodies against a synthetic peptide (aa 138-152) from HIV-1 Nef protein were produced and characterized. Three hybridoma lines producing monoclonal antibodies (MAbs) against the synthetic peptide were generated by fusion between P3-X63 Ag8.653 myeloma cells and BALB/c splenocytes from...... mice immunized with the synthetic peptide coupled to keyhole limpet hemocyanin (KLH). The hybridomas were screened and selected by ELISA with the peptide coupled to bovine serum albumin (BSA) immobilized to the polystyrene surface and specificity for the peptide was confirmed by competitive ELISA...

  8. Monoclonal antibodies against a synthetic peptide from human immunodeficiency virus type 1 Nef protein

    DEFF Research Database (Denmark)

    Steinaa, L; Wulff, A M; Saermark, T

    1994-01-01

    Monoclonal antibodies against a synthetic peptide (aa 138-152) from HIV-1 Nef protein were produced and characterized. Three hybridoma lines producing monoclonal antibodies (MAbs) against the synthetic peptide were generated by fusion between P3-X63 Ag8.653 myeloma cells and BALB/c splenocytes from...... mice immunized with the synthetic peptide coupled to keyhole limpet hemocyanin (KLH). The hybridomas were screened and selected by ELISA with the peptide coupled to bovine serum albumin (BSA) immobilized to the polystyrene surface and specificity for the peptide was confirmed by competitive ELISA with...

  9. Monoclonal antibodies against the iron regulated outer membrane Proteins of Acinetobacter baumannii are bactericidal

    Directory of Open Access Journals (Sweden)

    Goel Vikas

    2001-08-01

    Full Text Available Abstract Background Iron is an important nutrient required by all forms of life.In the case of human hosts,the free iron availability is 10-18M,which is far less than what is needed for the survival of the invading bacterial pathogen.To survive in such conditions, bacteria express new proteins in their outer membrane and also secrete iron chelators called siderophores. Results/ Discussion Acinetobacter baumannii ATCC 19606, a nosocomial pathogen which grows under iron restricted conditions, expresses four new outer membrane proteins,with molecular weight ranging from 77 kDa to 88 kDa, that are called Iron Regulated Outer Membrane Proteins (IROMPs. We studied the functional and immunological properties of IROMPs expressed by A.baumanii ATCC 19606.The bands corresponding to IROMPs were eluted from SDS-PAGE and were used to immunize BALB/c mice for the production of monoclonal antibodies. Hybridomas secreting specific antibodies against these IROMPs were selected after screening by ELISA and their reactivity was confirmed by Western Blot. The antibodies then generated belonged to IgM isotype and showed bactericidical and opsonising activities against A.baumanii in vitro.These antibodies also blocked siderophore mediated iron uptake via IROMPs in bacteria. Conclusion This proves that iron uptake via IROMPs,which is mediated through siderophores,may have an important role in the survival of A.baumanii inside the host,and helps establishing the infection.

  10. Production of anti-Gordonia amarae mycolic acid polyclonal antibody for detection of mycolic acid-containing bacteria in activated sludge foam.

    Science.gov (United States)

    Iwahori, K; Miyata, N; Takata, N; Morisada, S; Mochizuki, T

    2001-01-01

    Mycolic acid-containing actinomycetes (mycolata) are considered the causative agents of foaming of activated sludge and scum formation in activated sludge treatment plants. In this study, the production of anti-Gordonia amarae mycolic acid polyclonal antibodies was investigated. Rabbits were immunized with a conjugate of keyhole limpet hemocyanin and mycolic acids of G. amarae, which contained 48 to 56 carbon atoms (average, 52.0). Enzyme-linked immunosorbent assay (ELISA) demonstrated that the polyclonal antibodies could recognize cells of G. amarae ranging from 0.1 to 10 microg. The antibodies also reacted with other tested mycolata strains belonging to the genera Nocardia, Rhodococcus, Dietzia, Mycobacterium and Tsukamurella. However, reactivities against other gram-positive and gram-negative bacteria not containing mycolic acid were negligible or much lower. The results indicate that the anti-G. amarae mycolic acid antibodies show a reactivity selective for a group of mycolata involved in the foaming of activated sludge. PMID:16233121

  11. Protein biomarker enrichment by biomarker antibody complex elution for immunoassay biosensing.

    Science.gov (United States)

    Sabatte, Gwenola; Feitsma, Harma; Evers, Toon H; Prins, Menno W J

    2011-11-15

    It is very challenging to perform sample enrichment for protein biomarkers because proteins can easily change conformation and denature. In this paper we demonstrate protein enrichment suited for high-sensitivity integrated immuno-biosensing. The method enhances the concentration of the biomarkers and simultaneously removes matrix components that could interfere with the immunoassay. Biomarkers are captured using antibody coated magnetic particles and the biomarker antibody complexes are released by enzymatic elution. The eluted complexes are subsequently detected in a sandwich immunoassay biosensor. A scaling study of the enrichment process demonstrates an enrichment factor of 15 in buffer and plasma. We analyze the enrichment factor in terms of the three basic steps of the assay (capture, concentration, elution) and we quantify their respective efficiencies. The process is suited for integration into bio-analytical tools.

  12. The hypervariable region of Streptococcus pyogenes M protein escapes antibody attack by antigenic variation and weak immunogenicity

    DEFF Research Database (Denmark)

    Lannergård, Jonas; Gustafsson, Caj Ulrik Mattias; Waldemarsson, Johan;

    2011-01-01

    , we analyzed the clinically important HVR-containing M proteins of the human pathogen Streptococcus pyogenes. Antibodies elicited by M proteins were directed almost exclusively against the C-terminal part and not against the N-terminal HVR. Similar results were obtained for mice and humans...... with invasive S. pyogenes infection. Nevertheless, only anti-HVR antibodies protected efficiently against infection, as shown by passive immunizations. The HVR fused to an unrelated protein elicited no antibodies, implying that it is inherently weakly immunogenic. These data indicate that the M protein HVR...

  13. Cartilage oligomeric matrix protein specific antibodies are pathogenic

    DEFF Research Database (Denmark)

    Geng, Hui; Nandakumar, Kutty Selva; Pramhed, Anna;

    2012-01-01

    ABSTRACT: INTRODUCTION: Cartilage oligomeric matrix protein (COMP) is a major non-collagenous component of cartilage. Earlier, we developed a new mouse model for rheumatoid arthritis using COMP. This study was undertaken to investigate the epitope specificity and immunopathogenicity of COMP...... and the pathogenicity of mAbs was investigated by passive transfer experiments. RESULTS: B cell immunodominant epitopes were localized within 4 antigenic domains of the COMP but with preferential response to the epidermal growth factor (EGF)-like domain. Some of our anti-COMP mAbs showed interactions with the native...... form of COMP, which is present in cartilage and synovium. Passive transfer of COMP-specific mAbs enhanced arthritis when co-administrated with a sub-arthritogenic dose of a mAb specific to collagen type II. Interestingly, we found that a combination of 5 COMP mAbs was capable of inducing arthritis...

  14. Highly efficient antibody immobilization with multimeric protein Gs coupled magnetic silica nanoparticles

    Science.gov (United States)

    Lee, J. H.; Choi, H. K.; Chang, J. H.

    2011-10-01

    This work reports the immobilization of monomeric, dimeric and trimer protein Gs onto silica magnetic nanoparticles for self-oriented antibody immobilization. To achieve this, we initially prepared the silica-coated magnetic nanoparticle having about 170 nm diameters. The surface of the silica coated magnetic nanoparticles was modified with 3- aminopropyl-trimethoxysilane (APTMS) to chemically link to multimeric protein Gs. The conjugation of amino groups on the SiO2-MNPs to cysteine tagged in multimeric protein Gs was performed using a sulfo-SMCC coupling procedure. The binding efficiencies of monomer, dimer and trimer were 77 %, 67 % and 55 % respectively. However, the efficiencies of antibody immobilization were 70 %, 83 % and 95 % for monomeric, dimeric and trimeric protein G, respectively. To prove the enhancement of accessibility by using multimeric protein G, FITC labeled goat-anti-mouse IgG was treated to mouse IgG immobilized magnetic silica nanoparticles through multimeric protein G. FITC labeled goat anti-mouse IgGs were more easily bound to mouse IgG immobilized by trimeric protein G than others. Finally protein G bound silica magnetic nanoparticles were utilized to develop highly sensitive immunoassay to detect hepatitis B antigen.

  15. Effect of Bovine Papillomavirus E2 Protein-Specific Monoclonal Antibodies on Papillomavirus DNA Replication

    OpenAIRE

    Kurg, Reet; Parik, Jüri; Juronen, Erkki; Sedman, Tiina; Abroi, Aare; Liiv,Ingrid; Langel, Ülo; Ustav, Mart

    1999-01-01

    The bovine papillomavirus type 1 (BPV-1) E2 protein is the master regulator of papillomavirus replication and transcription. We have raised a panel of monoclonal antibodies (MAbs) against the BPV-1 E2 protein and used them to probe the structure and function of the protein. Five MAbs reacted with linear epitopes, and four MAbs recognized conformation-dependent epitopes which mapped within the C-terminal DNA-binding and dimerization domain. MAb 1E2 was able to recognize the replication- and tr...

  16. Photocleavable DNA barcode-antibody conjugates allow sensitive and multiplexed protein analysis in single cell

    Science.gov (United States)

    Agasti, Sarit S.; Liong, Monty; Peterson, Vanessa M.; Lee, Hakho; Weissleder, Ralph

    2012-01-01

    DNA barcoding is an attractive technology as it allows sensitive and multiplexed target analysis. However, DNA barcoding of cellular proteins remains challenging, primarily because barcode amplification and readout techniques are often incompatible with the cellular microenvironment. Here, we describe the development and validation of a photocleavable DNA barcode-antibody conjugate method for rapid, quantitative and multiplexed detection of proteins in single live cells. Following target binding, this method allows DNA barcodes to be photoreleased in solution, enabling easy isolation, amplification and readout. As a proof of principle, we demonstrate sensitive and multiplexed detection of protein biomarkers in a variety of cancer cells. PMID:23092113

  17. Compartmentation of hepatic fatty-acid-binding protein in liver cells and its effect on microsomal phosphatidic acid biosynthesis.

    Science.gov (United States)

    Bordewick, U; Heese, M; Börchers, T; Robenek, H; Spener, F

    1989-03-01

    Fatty-acid-binding proteins are known to occur in the cytosol of mammalian cells and to bind fatty acids and their CoA-esters. Application of the postembedding protein A-gold labeling method with antibody against the hepatic type fatty-acid-binding protein (hFABP) to cross-sections of liver cells and a newly developed gel-chromatographic immunofluorescence assay established qualitatively (1) that hFABP in mitochondria was confined to outer mitochondrial membranes, (2) the presence of this protein in microsomes and (3) that nuclei were also filled with hFABP. Quantitative data elaborated with a non-competitive ELISA confirmed these results. A significant difference to the distribution of cardiac FABP in heart muscle cells, where this type of protein was found in cytosol, matrix and nuclei, was observed (Börchers et al. (1989) Biochim. Biophys. Acta, in the press). hFABP-containing rat liver microsomes were incubated with long-chain acyl-CoAs in the presence of hFABP (isolated from rat liver cytosol) in a study on the acylation of sn-glycerol-3-phosphate and lysophosphatidic acid. Both acyltransferases were stimulated by addition of hFABP to the incubation medium. The morphological, immunochemical as well as kinetic data infer a direct interaction of hFABP with microsomal membranes in liver cells.

  18. Antibody Recognition of Porcine Circovirus Type 2 Capsid Protein Epitopes after Vaccination, Infection, and Disease▿†

    Science.gov (United States)

    Trible, Benjamin R.; Kerrigan, Maureen; Crossland, Nicholas; Potter, Megan; Faaberg, Kay; Hesse, Richard; Rowland, Raymond R. R.

    2011-01-01

    Open reading frame 2 (ORF2) of porcine circovirus type 2 (PCV2) codes for the 233-amino-acid capsid protein (CP). Baculovirus-based vaccines that express only ORF2 are protective against clinical disease following experimental challenge or natural infection. The goal of this study was to identify regions in CP preferentially recognized by sera from experimentally infected and vaccinated pigs and to compare these responses to those of pigs diagnosed with porcine circovirus-associated disease (PCVAD), including porcine multisystemic wasting syndrome (PMWS) and porcine dermatitis and nephropathy syndrome (PDNS). The approach was to react porcine sera with CP polypeptide fragments followed by finer mapping studies using overlapping oligopeptides that covered amino acids 141 to 200. The results showed that vaccinated pigs preferentially recognized only the largest polypeptide fragment, CP(43-233). A subset of experimentally infected pigs and pigs with PDNS showed strong reactivity against a CP oligopeptide, 169-STIDYFQPNNKR-180. Alanine scanning identified Y-173, F-174, Q-175, and K-179 as important for antibody recognition. The results from this study support the notion of PCV2 modulation of immunity, including antibody responses that may represent a precursor for disease. The recognition of CP(169-180) and other polypeptides provides opportunities to devise diagnostic tests for monitoring the immunological effectiveness of vaccination. PMID:21430122

  19. Antibodies against high-risk human papillomavirus proteins as markers for invasive cervical cancer.

    Science.gov (United States)

    Combes, Jean-Damien; Pawlita, Michael; Waterboer, Tim; Hammouda, Doudja; Rajkumar, Thangarajan; Vanhems, Philippe; Snijders, Peter; Herrero, Rolando; Franceschi, Silvia; Clifford, Gary

    2014-11-15

    Different human papillomavirus (HPV) genes are expressed during the various phases of the HPV life cycle and may elicit immune responses in the process towards malignancy. To evaluate their association with cervical cancer, antibodies against proteins from HPV16 (L1, E1, E2, E4, E6 and E7) and HPV18/31/33/35/45/52/58 (L1, E6 and E7) were measured in serum of 307 invasive cervical cancer cases and 327 controls from Algeria and India. Antibody response was evaluated using a glutathione S-transferase-based multiplex serology assay and HPV DNA detected from exfoliated cervical cells using a GP5+/6+-mediated PCR assay. Among HPV16 DNA-positive cases, seroprevalence of HPV16 antibodies ranged from 16% for HPV16 E1 to 50% for HPV16 E6 and all were significantly higher than controls. Seroprevalence of E6, E7 and L1 antibodies for HPV18 and for at least one of HPV31/33/35/45/52/58 were also higher in cases positive for DNA of the corresponding type (50% and 30% for E6 of HPV18 and HPV31/33/35/45/52/58 combined, respectively). E6 and E7 antibodies were rarely found in controls, but cross-reactivity was evident among cancer cases positive for DNA of closely phylogenetically-related HPV types. E6 or E7 antibodies against any of the eight HPV types were detected in 66.1% of all cervical cancer cases, as compared to 10.1% of controls. E6, and to a lesser extent E7, antibodies appear to be specific markers of HPV-related malignancy. However, even among cases positive for the same type of HPV DNA, approximately one-third of cervical cancer cases show no detectable immune response to either E6 or E7. PMID:24729277

  20. Absolute quantitation of proteins by Acid hydrolysis combined with amino Acid detection by mass spectrometry

    DEFF Research Database (Denmark)

    Mirgorodskaya, Olga A; Körner, Roman; Kozmin, Yuri P;

    2012-01-01

    Amino acid analysis is among the most accurate methods for absolute quantification of proteins and peptides. Here, we combine acid hydrolysis with the addition of isotopically labeled standard amino acids and analysis by mass spectrometry for accurate and sensitive protein quantitation....... Quantitation of less than 10 fmol of protein standards with errors below 10% has been demonstrated using this method (1)....

  1. Immunodiagnosis of Citrus leprosis virus C using a polyclonal antibody to an expressed putative coat protein.

    Science.gov (United States)

    Choudhary, Nandlal; Roy, Avijit; Guillermo, Leon M; Picton, D D; Wei, G; Nakhla, M K; Levy, L; Brlansky, R H

    2013-11-01

    Citrus leprosis virus C (CiLV-C), a causal agent for citrus leprosis disease, is present in South and Central America and is a threat for introduction into the U.S. citrus industry. A specific, inexpensive and reliable antibody based detection system is needed for the rapid identification of CiLV-C. The CiLV-C is very labile and has not been purified in sufficient amount for antibody production. The p29 gene of CiLV-C genome that codes for the putative coat protein (PCP) was codon optimized for expression in Escherichia coli and synthesized in vitro. The optimized gene was sub-cloned into the bacterial expression vector pDEST17 and transferred into E. coli BL21AI competent cells. The expression of PCP containing N-terminal His-tag was optimized by induction with l-arabinose. Induced cells were disrupted by sonication and expressed PCP was purified by affinity chromatography using Ni-NTA agarose. The purified expressed PCP was then used as an immunogen for injections into rabbits to produce polyclonal antibody (PAb). The PAb specific to the expressed PCP was identified using Western blotting. The antibody was successfully used to detect CiLV-C in the symptomatic CiLV-C infected tissues using double antibody sandwich-enzyme-linked-immunosorbent (DAS-ELISA), indirect ELISA and dot-blot immunoassay (DBIA) formats.

  2. Prophylactic and therapeutic activity of fully human monoclonal antibodies directed against Influenza A M2 protein

    Directory of Open Access Journals (Sweden)

    Gwerder Myriam

    2009-12-01

    Full Text Available Abstract Influenza virus infection is a prevalent disease in humans. Antibodies against hemagglutinin have been shown to prevent infection and hence hemagglutinin is the major constituent of current vaccines. Antibodies directed against the highly conserved extracellular domain of M2 have also been shown to mediate protection against Influenza A infection in various animal models. Active vaccination is generally considered the best approach to combat viral diseases. However, passive immunization is an attractive alternative, particularly in acutely exposed or immune compromized individuals, young children and the elderly. We recently described a novel method for the rapid isolation of natural human antibodies by mammalian cell display. Here we used this approach to isolate human monoclonal antibodies directed against the highly conserved extracellular domain of the Influenza A M2 protein. The identified antibodies bound M2 peptide with high affinities, recognized native cell-surface expressed M2 and protected mice from a lethal influenza virus challenge. Moreover, therapeutic treatment up to 2 days after infection was effective, suggesting that M2-specific monoclonals have a great potential as immunotherapeutic agents against Influenza infection.

  3. Identification of an immunogenic protein of Giardia lamblia using monoclonal antibodies generated from infected mice

    Directory of Open Access Journals (Sweden)

    Jael Quintero

    2013-08-01

    Full Text Available The humoral immune response plays an important role in the clearance of Giardia lamblia. However, our knowledge about the specific antigens of G. lamblia that induce a protective immune response is limited. The purpose of this study was to identify and characterise the immunogenic proteins of G. lamblia in a mouse model. We generated monoclonal antibodies (moAbs specific to G. lamblia (1B10, 2C9.D11, 3C10.E5, 3D10, 5G8.B5, 5F4, 4C7, 3C5 and 3C6 by fusing splenocytes derived from infected mice. Most of these moAbs recognised a band of ± 71 kDa (5G8 protein and this protein was also recognised by serum from the infected mice. We found that the moAbs recognised conformational epitopes of the 5G8 protein and that this antigen is expressed on the cell surface and inside trophozoites. Additionally, antibodies specific to the 5G8 protein induced strong agglutination (> 70-90% of trophozoites. We have thus identified a highly immunogenic antigen of G. lamblia that is recognised by the immune system of infected mice. In summary, this study describes the identification and partial characterisation of an immunogenic protein of G. lamblia. Additionally, we generated a panel of moAbs specific for this protein that will be useful for the biochemical and immunological characterisation of this immunologically interesting Giardia molecule.

  4. Prokaryotic expression of soluble Arabidopsis protein AtERF1 and preparation of its polyclonal antibodies

    Directory of Open Access Journals (Sweden)

    ZHANG Yu

    2013-08-01

    Full Text Available AtERF1 encodes a member of the ERF subfamily B-3 of ERF/AP2 transcription factor family.It has been demonstrated almost every member of the B3 subgroup of AP2/ERF genes is involved in defense responses in Arabidopsis.Codon usage within a gene is a critical determinant of achievable protein expression level in E.coli. Gene optimization,therefore,is an effective method for synthetic genes with the aim of enhancing soluble expression,particular in heterologous hosts.In this paper,the AtERF1 protein of Arabidopsis thaliana was expressed in Escherichia coli using its optimized DNA sequence for E.coli. and yielded high level of soluble AtERF-1 protein in recombinant E.coli. The AtERF1 protein was used as an antigen to immune rabbits and obtains high titer antibodies.The immunological specificity of the polyclonal antibodies to AtERF1 was confirmed by Western blot assay.The prepared antibody in this work would facilitate the further functional investigation of AtERF1 in biochemical levels in Arabidopsis anther development.

  5. Relative concentrations of serum neutralizing antibody to VP3 and VP7 proteins in adults infected with a human rotavirus.

    OpenAIRE

    Ward, R. L.; Knowlton, D R; Schiff, G M; Hoshino, Y.; Greenberg, H B

    1988-01-01

    Two outer capsid rotavirus proteins, VP3 and VP7, have been found to elicit neutralizing-antibody production, but the immunogenicity of these proteins during human rotavirus infection has not been determined. The relative amounts of serum neutralizing antibody against the VP3 and VP7 proteins of the CJN strain of human rotavirus were, therefore, determined in adult subjects before and after infection with this virus. Reassortant strains of rotavirus that contained the CJN gene segment for onl...

  6. Micro-indirect hemagglutination test for detection of antibodies to the Ibc protein of group B Streptococcus.

    OpenAIRE

    Thangavelu, C P; Koshi, G

    1980-01-01

    A micro-indirect hemagglutination test was developed for detecting antibody against the Ibc protein of group B Streptococcus. Formalin-preserved, tanned sheep erythrocytes were sensitized with a partially purified preparation of Ibc protein from a type Ic strain of group B streptococci. A total of 76% of 103 sera from pregnant and nonpregnant women had demonstrable antibody against this protein, with titers ranging from 10 to 320. Examination of five pairs of mother and cord sera revealed pas...

  7. Reaction of Native and Denatured Brucella abortus (S19) Proteins with Antibody Using Affinity Chromatography and Immunoblotting

    OpenAIRE

    Karimi, R.; A Mostafaie; B. Tabaraie; Y. Bahrami; J. Abdolalizadeh

    2005-01-01

    Western blotting or immunoblotting commonly use for study of reaction between antigens and antibodies. Denaturation of many proteins in immunoblotting can affect greatly the reactivity of antibodies and outcome of the procedure.In this study proteins of Brucella abortus (S19) was extracted by a mild method and reaction of the extracted proteins with serum of infected human and goat and immunized rabbit compared by affinity chromatography and immunoblotting. Gamma globulin (m...

  8. Study of the Mn-binding sites in photosystem II using antibodies raised against lumenal regions of the D1 and D2 reaction center proteins

    Energy Technology Data Exchange (ETDEWEB)

    Dalmasso, E.A.

    1992-04-01

    The experiments discussed in this thesis focus on identifying the protein segments or specific amino acids which provide ligands to the Mn cluster of photosystem II (PS II). This Mn cluster plays a central role in the oxygen-evolving complex (OEC) of PS II. The Mn cluster is thought to be bound by lumenal regions of the PS II reaction center proteins known as D1 and D2. First, several peptides were synthesized which correspond to specific lumenal segments of the D1 and D2 proteins. Next, polyclonal antibodies were successfully elicited using three of these peptides. The peptides recognized by these antibodies correspond to protein segments of the spinach reaction center proteins: Ile-321 to Ala-344 of D1 (D1-a), Asp-319 to Arg-334 of D1 (D1-b), and Val-300 to Asn-319 of D2 (D2-a). These antibodies were then used in assays which were developed to structurally or functionally probe the potential Mn-binding regions of the D1 and D2 proteins.

  9. Expression and purification of the nucleocapsid protein of Schmallenberg virus, and preparation and characterization of a monoclonal antibody against this protein.

    Science.gov (United States)

    Zhang, Yongning; Wu, Shaoqiang; Wang, Jianchang; Wernike, Kerstin; Lv, Jizhou; Feng, Chunyan; Zhang, Jihong; Wang, Caixia; Deng, Junhua; Yuan, Xiangfen; Lin, Xiangmei

    2013-11-01

    Schmallenberg virus (SBV) is a novel orthobunyavirus that primarily infects ruminants such as cattle, sheep and goats. The nucleocapsid (N) protein of SBV has been shown to be an ideal target antigen for serological detection. To prepare a monoclonal antibody (mAb) against the N protein, the full-length coding sequence of the SBV N gene was cloned into pET-28a-c(+) and pMAL-c5X vectors to generate two recombinant plasmids, which were expressed in Escherichia coli BL21 as histidine (His)-tagged (His-SBV-N) and maltose-binding protein (MBP)-tagged (MBP-SBV-N) fusion proteins, respectively. After affinity purification of His-SBV-N with Ni-NTA agarose and MBP-SBV-N with amylose resin, His-SBV-N was used to immunize BALB/c mice, while MBP-SBV-N was utilized to screen for mAb-secreting hybridomas. Six hybridoma cell lines stably secreting mAbs against N were obtained. Clone 2C8 was selected for further study because of its rapid growth characteristics in vitro and good reactivity with recombinant SBV N proteins in enzyme-linked immunosorbent assays. The epitope recognized by 2C8 is located at amino acids 51-76 of the SBV N protein. Western blot analyses showed that 2C8 reacts with both recombinant SBV N proteins and SBV isolates. It is also cross-reactive with the N proteins of genetically related Shamonda, Douglas and Akabane viruses, but not with the Rift Valley fever virus N protein. The successful preparation of recombinant N proteins and mAbs provides valuable materials that can be used in the serological diagnosis of SBV. PMID:23988909

  10. Comprehensive Identification of Immunodominant Proteins of Brucella abortus and Brucella melitensis Using Antibodies in the Sera from Naturally Infected Hosts

    Directory of Open Access Journals (Sweden)

    Gamal Wareth

    2016-04-01

    Full Text Available Brucellosis is a debilitating zoonotic disease that affects humans and animals. The diagnosis of brucellosis is challenging, as accurate species level identification is not possible with any of the currently available serology-based diagnostic methods. The present study aimed at identifying Brucella (B. species-specific proteins from the closely related species B. abortus and B. melitensis using sera collected from naturally infected host species. Unlike earlier reported investigations with either laboratory-grown species or vaccine strains, in the present study, field strains were utilized for analysis. The label-free quantitative proteomic analysis of the naturally isolated strains of these two closely related species revealed 402 differentially expressed proteins, among which 63 and 103 proteins were found exclusively in the whole cell extracts of B. abortus and B. melitensis field strains, respectively. The sera from four different naturally infected host species, i.e., cattle, buffalo, sheep, and goat were applied to identify the immune-binding protein spots present in the whole protein extracts from the isolated B. abortus and B. melitensis field strains and resolved on two-dimensional gel electrophoresis. Comprehensive analysis revealed that 25 proteins of B. abortus and 20 proteins of B. melitensis were distinctly immunoreactive. Dihydrodipicolinate synthase, glyceraldehyde-3-phosphate dehydrogenase and lactate/malate dehydrogenase from B. abortus, amino acid ABC transporter substrate-binding protein from B. melitensis and fumarylacetoacetate hydrolase from both species were reactive with the sera of all the tested naturally infected host species. The identified proteins could be used for the design of serological assays capable of detecting pan-Brucella, B. abortus- and B. melitensis-specific antibodies.

  11. Comprehensive Identification of Immunodominant Proteins of Brucella abortus and Brucella melitensis Using Antibodies in the Sera from Naturally Infected Hosts.

    Science.gov (United States)

    Wareth, Gamal; Eravci, Murat; Weise, Christoph; Roesler, Uwe; Melzer, Falk; Sprague, Lisa D; Neubauer, Heinrich; Murugaiyan, Jayaseelan

    2016-01-01

    Brucellosis is a debilitating zoonotic disease that affects humans and animals. The diagnosis of brucellosis is challenging, as accurate species level identification is not possible with any of the currently available serology-based diagnostic methods. The present study aimed at identifying Brucella (B.) species-specific proteins from the closely related species B. abortus and B. melitensis using sera collected from naturally infected host species. Unlike earlier reported investigations with either laboratory-grown species or vaccine strains, in the present study, field strains were utilized for analysis. The label-free quantitative proteomic analysis of the naturally isolated strains of these two closely related species revealed 402 differentially expressed proteins, among which 63 and 103 proteins were found exclusively in the whole cell extracts of B. abortus and B. melitensis field strains, respectively. The sera from four different naturally infected host species, i.e., cattle, buffalo, sheep, and goat were applied to identify the immune-binding protein spots present in the whole protein extracts from the isolated B. abortus and B. melitensis field strains and resolved on two-dimensional gel electrophoresis. Comprehensive analysis revealed that 25 proteins of B. abortus and 20 proteins of B. melitensis were distinctly immunoreactive. Dihydrodipicolinate synthase, glyceraldehyde-3-phosphate dehydrogenase and lactate/malate dehydrogenase from B. abortus, amino acid ABC transporter substrate-binding protein from B. melitensis and fumarylacetoacetate hydrolase from both species were reactive with the sera of all the tested naturally infected host species. The identified proteins could be used for the design of serological assays capable of detecting pan-Brucella, B. abortus- and B. melitensis-specific antibodies. PMID:27144565

  12. Trans-splicing as a novel method to rapidly produce antibody fusion proteins

    Energy Technology Data Exchange (ETDEWEB)

    Iwasaki, Ryohei; Kiuchi, Hiroki [Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Ihara, Masaki [Department of Bioengineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Mori, Toshihiro; Kawakami, Masayuki [Lifescience Lab. R and D, Fujifilm Co., 577 Ushijima, Kaisei-machi, Ashigarakami-gun, Kanagawa 258-8577 (Japan); Ueda, Hiroshi, E-mail: hueda@chembio.t.u-tokyo.ac.jp [Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Department of Bioengineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2009-07-03

    To cultivate the use of trans-splicing as a novel means to rapidly express various antibody fusion proteins, we tried to express antibody-reporter enzyme fusions in a COS-1 co-transfection model. When a vector designed to induce trans-splicing with IgH pre-mRNA was co-transfected with a vector encoding the mouse IgM locus, the expression of V{sub H}-secreted human placental alkaline phosphatase (SEAP) as well as Fab-SEAP were successfully expressed both in mRNA and protein levels. Especially, the vectors encoding complementary sequence to S{mu} as a binding domain was accurate and efficient, producing trans-spliced mRNA of up to 2% of cis-spliced one. Since S{mu} sequence should exist in every IgH pre-mRNA, our finding will lead to the rapid production and analysis of various antibody-enzyme fusions suitable for enzyme-linked immunosorbent assay (ELISA) or antibody-dependent enzyme prodrug therapy (ADEPT).

  13. Trans-splicing as a novel method to rapidly produce antibody fusion proteins

    International Nuclear Information System (INIS)

    To cultivate the use of trans-splicing as a novel means to rapidly express various antibody fusion proteins, we tried to express antibody-reporter enzyme fusions in a COS-1 co-transfection model. When a vector designed to induce trans-splicing with IgH pre-mRNA was co-transfected with a vector encoding the mouse IgM locus, the expression of VH-secreted human placental alkaline phosphatase (SEAP) as well as Fab-SEAP were successfully expressed both in mRNA and protein levels. Especially, the vectors encoding complementary sequence to Sμ as a binding domain was accurate and efficient, producing trans-spliced mRNA of up to 2% of cis-spliced one. Since Sμ sequence should exist in every IgH pre-mRNA, our finding will lead to the rapid production and analysis of various antibody-enzyme fusions suitable for enzyme-linked immunosorbent assay (ELISA) or antibody-dependent enzyme prodrug therapy (ADEPT).

  14. Site specific incorporation of keto amino acids into proteins

    Science.gov (United States)

    Schultz, Peter G.; Wang, Lei

    2011-03-22

    Compositions and methods of producing components of protein biosynthetic machinery that include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of tRNAs/synthetases, which incorporate keto amino acids into proteins are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins with keto amino acids using these orthogonal pairs.

  15. The protein digestibility-corrected amino acid score

    NARCIS (Netherlands)

    Schaafsma, G.

    2000-01-01

    The protein digestibility–corrected amino acid score (PDCAAS) has been adopted by FAO/WHO as the preferred method for the measurement of the protein value in human nutrition. The method is based on comparison of the concentration of the first limiting essential amino acid in the test protein with th

  16. Development of 2 types of competitive enzyme-linked immunosorbent assay for detecting antibodies to the rinderpest virus using a monoclonal antibody for a specific region of the hemagglutinin protein.

    Science.gov (United States)

    Khamehchian, S; Madani, R; Rasaee, M J; Golchinfar, F; Kargar, R

    2007-06-01

    A competitive enzyme-linked immunosorbent assay (C-ELISA) has been developed and standardized for the detection of antibodies to the rinderpest virus (RPV) in sera from cattle, sheep, and goats. The test is specific for rinderpest because it does not detect antibodies to peste-des-petits-ruminants virus (PPRV). The test depends on the ability of the monoclonal antibody (MAb) directed against the hemagglutinin (H) protein of RPV to compete with the binding of RPV antibodies in the positive serum to the H protein of this virus. This MAb recognized a region from amino acids 575 to 583 on the H protein of RPV that is unique to the RPV H protein and is not present on the hemagglutinin-neuraminidase protein of PPRV. Another C-ELISA (peptide C-ELISA) was set up using this specific region as an antigen. A threshold value of 64.4% inhibition was established for the RPV C-ELISA, with 90 known RPV-negative and 30 RPV-positive serum samples. Using common serum samples, a cutoff value of 43.0% inhibition for the peptide C-ELISA was established. Based on statistical analysis, the overall sensitivity and specificity of the RPV C-ELISA, relative to those of a commercial kit, were found to be 90.00% and 103.33%, respectively. However, the sensitivity and specificity of the peptide C-ELISA were found to be 180.00% and 73.33%, respectively. Although a common MAb in 2 new C-ELISA systems was used, variation in their percent inhibition, due to the use of different antigens, was observed. Taking into consideration the difference in percent inhibition of the 2 described assays and the commercial kit (50%), it was found that the RPV C-ELISA and the peptide C-ELISA are more specific and sensitive tools than the commercial kit for assessing herd immune status and for epidemiologic surveillance. PMID:17668032

  17. Antibodies against N‑homocysteinylated proteins and their determinants in patients on long‑term hemodialysis

    Directory of Open Access Journals (Sweden)

    Marek Kolarz

    2010-06-01

    Full Text Available INTRODUCTION: The factors that determine the level of antibodies against N‑homocysteinylated (N‑Hcy proteins have not been established so far. The clinical significance of these antibodies and their effect on cardiovascular (CV risk in patients with end‑stage renal disease (ESRD are still unknown. OBJECTIVES: The aim of this study was to identify the factors that determine the level of antibodies against N‑Hcyalbumin and N‑Hcy hemoglobin in patients on long‑term hemodialysis (HD. PATIENTS AND METHODS: The study involved 247 subjects on long-term HD (110 women, 137 men; age range, 23–89 years and 60 controls matched for age, sex, and CV risk factors (serum creatinine level <140 μmol/l. Serum antibodies against N‑Hcyalbumin and N‑Hcyhemoglobin were determined using an in‑house enzyme‑linked immunosorbent assay. Total homocysteine (tHcy, folate, and 8‑isoprostaglandin F2α (8‑iso‑PGF 2α were also measured. RESULTS: Patients on HD had higher serum levels of anti‑N‑Hcy‑albumin (absorbancy at 490 nm: 0.56 [0.49–0.623] vs. 0.259 [0.198–0.338], P <0.0001 and anti‑N‑Hcy‑hemoglobin antibodies (0.659 [0.597–0.723] vs. 0.379 [0.289–0.442], P <0.0001 as compared with controls. The level of both antibodies correlated with tHcy (r = 0.56, P <0.0001 and r = 0.67, P <0.0001, respectively, 8‑iso‑PGF 2α (r = 0.48, P <0.0001 and r = 0.63, P <0.0001, respectively, and folate (r = –0.18, P = 0.0054 and r = –0.38, P <0.0001, respectively, but not with HD duration, the initial cause of ESRD, and CV comorbidity. CONCLUSIONS: In HD patients, tHcy is an independent predictor of antibodies against N‑Hcy proteins. Folate and 8‑iso‑PGF 2α concentrations were not independently associated with the levels of both antibodies.

  18. Novel Phospholipid-Protein Conjugates Allow Improved Detection of Antibodies in Patients with Autoimmune Diseases

    DEFF Research Database (Denmark)

    Samuelsen, Simone V; Maity, Arindam; Nybo, Mads;

    2016-01-01

    structural features of biologically active antigens into account and leads to low reliability and poor scientific test value. Here we describe novel phospholipid-protein conjugates for specific detection of human autoimmune antibodies. Our synthetic approach includes mild oxidation of synthetic phospholipid......Reliable measurement of clinically relevant autoimmune antibodies toward phospholipid-protein conjugates is highly desirable in research and clinical assays. To date, the development in this field has been limited to the use of natural heterogeneous antigens. However, this approach does not take...... in Denmark (n = 34) and the USA (n = 27 and n = 14). Afterwards we analyzed correlation of the obtained autoantibody titers with clinical parameters for each patient. Our results prove that using novel antigens clinically relevant autoantibodies can be detected with high repeatability, sensitivity...

  19. Injection of an antibody against a p21 c-Ha-ras protein inhibits cleavage in axolotl eggs.

    OpenAIRE

    Baltus, E; Hanocq-Quertier, J; Hanocq, F.; Brachet, J.

    1988-01-01

    The presence of a ras protein was demonstrated in cleaving axolotl eggs by selective immunoprecipitation with a polyclonal antibody against a peptide encoded by the c-Ha-ras oncogene, cellular homolog of the v-Ha-ras oncogene of Harvey rat sarcoma virus. Injection of this antibody into axolotl oocytes subjected to progesterone treatment does not prevent meiotic maturation. Injection of the same antibody into a blastomere of axolotl eggs at the 2- or 4-cell stage causes cleavage arrest in the ...

  20. Localization of the catalytic subunit of cyclic AMP-dependent. Protein kinase in cultured cells using a specific antibody

    OpenAIRE

    1982-01-01

    We developed a specific antibody to the catalytic subunit (C-subunit) of cyclic AMP-dependent protein kinase and used it to localize C- subunit in cultured cells. C-subunit antigen was purified from bovine cardiac muscle and cross-linked to hemocyanin with glutaraldehyde. Immunized goat serum showed a low titer of antibody after boosting; it was enriched 100-fold by affinity chromatography on catalytic subunit- Sepharose. The antibody immunoprecipitated C-subunit from type I and type II holoe...

  1. Western Blot Detection of Human Anti-Chikungunya Virus Antibody with Recombinant Envelope 2 Protein.

    Science.gov (United States)

    Yang, Zhaoshou; Lee, Jihoo; Ahn, Hye-Jin; Chong, Chom-Kyu; Dias, Ronaldo F; Nam, Ho-Woo

    2016-04-01

    Chikungunya virus (CHIKV), a tropical pathogen, has re-emerged and has massive outbreaks abruptly all over the world. Containing many dominant epitopes, the envelope E2 protein of CHIKV has been explored for the vaccination or diagnosis. In the present study, the antigenicity of a recombinant expressed intrinsically disorder domain (IUD) of E2 was tested for the detection of the antibody against CHIKV through western blot method. The gene of the IUD of E2 was inserted into 2 different vectors and expressed as recombinant GST-E2 and recombinant MBP-E2 fusion protein, respectively. Two kinds of fusion proteins were tested with 30 CHIKV patient sera and 30 normal sera, respectively. Both proteins were detected by 25 patients sera (83.3%) and 1 normal serum (3.3%). This test showed a relatively high sensitivity and very high specificity of the recombinant E2 proteins to be used as diagnostic antigens against CHIKV infection. PMID:27180586

  2. Development of robust antibody purification by optimizing protein-A chromatography in combination with precipitation methodologies.

    Science.gov (United States)

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

    2015-11-01

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

  3. Development of a protein biochip to identify 6 monoclonal antibodies against subtypes of recombinant human interferons.

    Science.gov (United States)

    Xu, Zhenshan; Du, Weidong; Zhang, Ping; Wang, Xuan; Ma, Xueling; Shi, Liqin; Song, Lihua

    2010-04-01

    Recombinant human interferons (rhIFNs) are broadly used as effective therapeutic agents with antiviral, antitumor, and immune-modulating properties. Advances in protein biochip technology have benefited the medical community greatly, making true parallelism, miniaturization, and high throughput possible. In this study, 5 rhIFN proteins (IFN-alpha1b, IFN-alpha2a, IFN-alpha2b, IFN-beta, and IFN-gamma) were immobilized onto an N-hydroxysuccinimide (NHS)-modified gold-based biochip. The protein biochip was incubated with 6 specific mouse IgG antibodies (AK1, AK2, AK3, AK4, BK1, and CK1) against the human IFNs and then with Cy3-conjugated goat anti-mouse IgG antibody. The results showed that monoclonal antibody AK1 presented a unique binding characteristic to IFN-alpha1b. AK2 reacted in immunoassays equally with IFN-alpha2a and IFN-alpha2b. AK3 detected IFN-alpha1b, IFN-alpha2a, and IFN-alpha2b. AK4 had positive immunological responses directed to both IFN-alpha1b and IFN-alpha2b. Monoclonal antibodies BK1 and CK1 recognized epitope of IFN-beta and IFN-gamma, specifically. The assay specificity of the biochip was further confirmed by enzyme-linked immunosorbent assay (ELISA) and western blotting. Finally, 88 serum samples from patients treated with rhIFN-alpha2b were simultaneously tested on a single biochip. The result demonstrated that 6.8% (6 of 88 cases) presented positive reactions to anti-IFN-alpha2b antibodies, indicating that the patients under rhIFN-alpha2b therapy produced neutralized antibody against the IFN. The biochip format would offer a competitive alternative tool not only for facilitating characterization of IFN subtypes but also potentially for enabling clinical serum detection of corresponding antibodies directed against IFNs. PMID:20230300

  4. Intrathecal-specific glutamic acid decarboxylase antibodies at low titers in autoimmune neurological disorders.

    Science.gov (United States)

    Sunwoo, Jun-Sang; Chu, Kon; Byun, Jung-Ick; Moon, Jangsup; Lim, Jung-Ah; Kim, Tae-Joon; Lee, Soon-Tae; Jung, Keun-Hwa; Park, Kyung-Il; Jeon, Daejong; Jung, Ki-Young; Kim, Manho; Lee, Sang Kun

    2016-01-15

    Autoantibodies to glutamic acid decarboxylase (Gad-Abs) are implicated in various neurological syndromes. The present study aims to identify intrathecal-specific GAD-Abs and to determine clinical manifestations and treatment outcomes. Nineteen patients had GAD-Abs in cerebrospinal fluid but not in paired serum samples. Neurological syndromes included limbic encephalitis, temporal lobe epilepsy, cerebellar ataxia, autonomic dysfunction, and stiff-person syndrome. Immunotherapy had beneficial effects in 57.1% of patients, and the patients with limbic encephalitis responded especially well to immunotherapy. Intrathecal-specific antibodies to GAD at low titers may appear as nonspecific markers of immune activation within the central nervous system rather than pathogenic antibodies causing neuronal dysfunction. PMID:26711563

  5. Monoclonal Antibodies Directed Against the Outer Membrane Protein of Bordetella avium

    OpenAIRE

    Liu, Guanhua; Liang, Manfei; Zuo, Xuemei; Zhao, Xue; Guo, Fanxia; Yang, Shifa; Zhu, Ruiliang

    2013-01-01

    Bordetella avium is the etiologic agent of coryza and rhinotracheitis in poultry. This respiratory disease is responsible for substantial economic losses in the poultry industry. Monoclonal antibodies (MAbs) were produced against the outer membrane proteins (OMPs) of B. avium isolated from diseased chickens. BALB/c mice were immunized with the extracted B. avium OMPs. Then the splenocytes from immunized mice and SP2/0 myeloma cells were fused using PEG 4000. Three stable hybridoma clones (des...

  6. Immunocytochemical localization of microtubule-associated protein 1 in rat cerebellum using monoclonal antibodies

    OpenAIRE

    1984-01-01

    Immunohistochemical staining with monoclonal antibodies showed that microtubule-associated protein 1 (MAP1) has a restricted cellular distribution in the rat cerebellum. Anti-MAP1 staining was found only in neurons, where it was much stronger in dendrites than in axons. There were striking variations in the apparent concentration of MAP1 in different classes of neurons. Purkinje cells were the most strongly labeled, while granule cell neurons gave a faint, threshold-level reaction with the an...

  7. Antigenisitas, Sensitivitas, dan Spesifisitas Protein Toxocara canis pada Pemeriksaan Antibodi Serum Mencit dengan Indirect-ELISA

    OpenAIRE

    Sri Subekti Bendryman; Kusnoto .; Tutik Juniastuti

    2015-01-01

    The aim of this research were to determine antigenicity, sensitivity, and specificity of Toxocara canisprotein used as antigen in indirect-ELISA for the detection antibody against the worm in the infected hostin order to proper diagnose kit. The design used was true experimental, with Post-test Only ControlGroups Design. Mouse was immunized with various worm homogenates used to antigenicity, sensitivityand specificity tests of T. canis protein with indirect-ELISA technique. The independence v...

  8. Comparison of different monoclonal antibodies against immunosuppressive proteins of Ascaris suum

    OpenAIRE

    T.M. Oshiro; A. Rafael; C.S. Enobe; Fernandes, I; Macedo-Soares, M.F.

    2004-01-01

    The extract of Ascaris suum suppresses the humoral and cellular immune responses to unrelated antigens in the mouse. In order to further characterize the suppressive components of A. suum, we produced specific monoclonal antibodies which can provide an important tool for the identification of these proteins. The A. suum immunosuppressive fractions isolated by gel filtration from an extract of adult worms were used to immunize BALB/c mice. Popliteal lymph node cells taken from the immunized an...

  9. Demonstration of antigenic variation among rabies virus isolates by using monoclonal antibodies to nucleocapsid proteins.

    OpenAIRE

    Smith, J S; Reid-Sanden, F L; Roumillat, L. F.; Trimarchi, C; Clark, K; Baer, G M; Winkler, W G

    1986-01-01

    Rabies virus isolates from terrestrial animals in six areas of the United States were examined with a panel of monoclonal antibodies to nucleocapsid proteins. Characteristic differences in immunofluorescence reactions permitted the formation of four antigenically distinct reaction groups from the 231 isolates tested. The geographic distribution of these groups corresponded well with separate rabies enzootic areas recognized by surveillance of sylvatic rabies in the United States. Distinctive ...

  10. Regulation of intestinal protein metabolism by amino acids.

    Science.gov (United States)

    Bertrand, Julien; Goichon, Alexis; Déchelotte, Pierre; Coëffier, Moïse

    2013-09-01

    Gut homeostasis plays a major role in health and may be regulated by quantitative and qualitative food intake. In the intestinal mucosa, an intense renewal of proteins occurs, at approximately 50% per day in humans. In some pathophysiological conditions, protein turnover is altered and may contribute to intestinal or systemic diseases. Amino acids are key effectors of gut protein turnover, both as constituents of proteins and as regulatory molecules limiting intestinal injury and maintaining intestinal functions. Many studies have focused on two amino acids: glutamine, known as the preferential substrate of rapidly dividing cells, and arginine, another conditionally essential amino acid. The effects of glutamine and arginine on protein synthesis appear to be model and condition dependent, as are the involved signaling pathways. The regulation of gut protein degradation by amino acids has been minimally documented until now. This review will examine recent data, helping to better understand how amino acids regulate intestinal protein metabolism, and will explore perspectives for future studies.

  11. Kinetics of Antibody Aggregation at Neutral pH and Ambient Temperatures Triggered by Temporal Exposure to Acid.

    Science.gov (United States)

    Imamura, Hiroshi; Honda, Shinya

    2016-09-15

    The purification process of an antibody in manufacturing involves temporal exposure of the molecules to low pH followed by neutralization-pH-shift stress-which causes aggregation. It remains unclear how aggregation triggered by pH-shift stress grows at neutral pH and how it depends on the temperature in an ambient range. We used static and dynamic light scattering to monitor the time-dependent evolution of the aggregate size of the pH-shift stressed antibody between 4.0 and 40.0 °C. A power-law relationship between the effective molecular weight and the effective hydrodynamic radius was found, indicating that the aggregates were fractal with a dimension of 1.98. We found that the aggregation kinetics in the lower-temperature range, 4.0-25.0 °C, were well described by the Smoluchowski aggregation equation. The temperature dependence of the effective aggregation rate constant gave 13 ± 1 kcal/mol of endothermic activation energy. Temporal acid exposure creates an enriched population of unfolded protein molecules that are competent of aggregating. Therefore, the energetically unfavorable unfolding step is not required and the aggregation proceeds faster. These findings provide a basis for predicting the growth of aggregates during storage under practical, ambient conditions. PMID:27537343

  12. The clinical significance of fatty acid binding proteins

    OpenAIRE

    Barbara Choromańska; Piotr Myśliwiec; Jacek Dadan; Hady Razak Hady; Adrian Chabowski

    2011-01-01

    Excessive levels of free fatty acids are toxic to cells. The human body has evolved a defense mechanism in the form of small cytoplasmic proteins called fatty acid binding proteins (FABPs) that bind long-chain fatty acids (LCFA), and then refer them to appropriate intracellular disposal sites (oxidation in mitochondria and peroxisomes or storage in the endoplasmic reticulum). So far, nine types of these proteins have been described, and their name refers to the place in which they were first ...

  13. Enhanced neutralization potency of botulinum neurotoxin antibodies using a red blood cell-targeting fusion protein.

    Directory of Open Access Journals (Sweden)

    Sharad P Adekar

    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.

  14. Selection, affinity maturation, and characterization of a human scFv antibody against CEA protein

    International Nuclear Information System (INIS)

    CEA is a tumor-associated antigen abundantly expressed on several cancer types, including those naturally refractory to chemotherapy. The selection and characterization of human anti-CEA single-chain antibody fragments (scFv) is a first step toward the construction of new anticancer monoclonal antibodies designed for optimal blood clearance and tumor penetration. The human MA39 scFv, selected for its ability to recognize a CEA epitope expressed on human colon carcinomas, was first isolated from a large semi-synthetic ETH-2 antibody phage library, panned on human purified CEA protein. Subsequently, by in vitro mutagenesis of a gene encoding for the scFv MA39, a new library was established, and new scFv antibodies with improved affinity towards the CEA cognate epitope were selected and characterized. The scFv MA39 antibody was affinity-maturated by in vitro mutagenesis and the new scFv clone, E8, was isolated, typed for CEA family member recognition and its CEACAM1, 3 and 5 shared epitope characterized for expression in a large panel of human normal and tumor tissues and cells. The binding affinity of the scFv E8 is in a range for efficient, in vivo, antigen capture in tumor cells expressing a shared epitope of the CEACAM1, 3 and 5 proteins. This new immunoreagent meets all criteria for a potential anticancer compound: it is human, hence poorly or not at all immunogenic, and it binds selectively and with good affinity to the CEA epitope expressed by metastatic melanoma and colon and lung carcinomas. Furthermore, its small molecular size should provide for efficient tissue penetration, yet give rapid plasma clearance

  15. Occurrence of antibodies against insect virus proteins in mammals: simple model to differentiate between passive exposure and active virus growth.

    Science.gov (United States)

    Moore, N F; McKnight, L; Tinsley, T W

    1981-02-01

    Antibodies against an "enterovirus-like" virus of insects, cricket paralysis virus, occur in the sera of domestic animals. When these antibodies were used in combination with the immunoprecipitation of radiolabeled virus proteins from infected Drosophila cells in culture, it could be demonstrated that the animals were exposed to preformed virus. PMID:6260677

  16. Occurrence of antibodies against insect virus proteins in mammals: simple model to differentiate between passive exposure and active virus growth.

    OpenAIRE

    Moore, N F; McKnight, L.; Tinsley, T. W.

    1981-01-01

    Antibodies against an "enterovirus-like" virus of insects, cricket paralysis virus, occur in the sera of domestic animals. When these antibodies were used in combination with the immunoprecipitation of radiolabeled virus proteins from infected Drosophila cells in culture, it could be demonstrated that the animals were exposed to preformed virus.

  17. Antibodies against Mycobacterial Proteins as Biomarkers for HIV-Associated Smear-Negative Tuberculosis

    OpenAIRE

    Siev, Michael; Wilson, Douglas; Kainth, Supreet; Kasprowicz, Victoria O.; Feintuch, Catherine M.; Jenny-Avital, Elizabeth R.; Achkar, Jacqueline M.

    2014-01-01

    Serology data are limited for patients with sputum smear-negative HIV-associated active tuberculosis (TB). We evaluated the serum antibody responses against the mycobacterial proteins MPT51, MS, and echA1 and the 38-kDa protein via enzyme-linked immunosorbent assay (ELISA) in South African (S.A.) HIV-positive (HIV+) smear-negative TB patients (n = 56), U.S. HIV+ controls with a positive tuberculin skin test (TST+; n = 21), and S.A. HIV-negative (HIV−) (n = 18) and HIV+ (n = 24) controls. TB p...

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

    OpenAIRE

    Sakti, Setyawan P.; Nur Chabibah; Ayu, Senja P.; Masdiana C. Padaga; Aulanni’am Aulanni’am

    2016-01-01

    Adulteration of goat milk is usually done using cow’s milk product. Cow milk is used as it is widely available and its price is cheaper compared to goat milk. This paper shows a development of candidate tools for milk adulteration using cow milk. A quartz crystal microbalance immunosensor was developed using commercial crystal resonator and polyclonal antibody specific to cow milk protein. A specific protein at 208 KDa is found only in cow milk and does not exist in goat milk. The existence o...

  19. Microspectrophotometric quantitation of nucleic acid and protein in irradiated epidermis.

    Science.gov (United States)

    Conti, C J; Giménez, I B; Cabrini, R L

    1976-03-01

    Nucleic acid and proteins of newborn rat tail subjected to local X-irradiation were microspectrophotometrically studied. Feulgen, gallocyanine chrom-alum and naphthol yellow S methods were performed for demonstration of DNA, total nucleic acid and proteins respectively. The amount of proteins and total nucleic acid increases concomitantly with reactional acanthosis. However, the proteins and nucleic acid decrease as from day 3 post-irradiation. A tentative interpretation of the results would point to a giantization of the epidermic cells not only caused by aqueous imbition but also by an actual increase of the cellular protoplasm. PMID:1258094

  20. Microspectrophotometric quantitation of nucleic acid and protein in irradiated epidermis

    International Nuclear Information System (INIS)

    Nucleic acid and proteins of newborn rat tail epidermis subjected to local X-irradiation were microspectrophotometrically studied. Feulgen, gallocyanine chrom-alum and naphthol yellow S methods were performed for demonstration of DNA, total nucleic acid and proteins respectively. The amount of proteins and total nucleic acid increases concomitantly with reactional acanthosis. However, the proteins and nucleic acid decrease as from day 3 post-irradiation. A tentative interpretation of the results would point to a giantization of the epidermic cells not only caused by aqueous imbition but also by an actual increase of the cellular protoplasm. (orig.)

  1. Nanopore biosensors for detection of proteins and nucleic acids

    NARCIS (Netherlands)

    Maglia, Giovanni; Soskine, Mikhael

    2014-01-01

    Described herein are nanopore biosensors based on a modified cytolysin protein. The nanopore biosensors accommodate macromoiecules including proteins and nucleic acids, and may additionally comprise ligands with selective binding properties.

  2. Fatty acid acylation of proteins: specific roles for palmitic, myristic and caprylic acids

    Directory of Open Access Journals (Sweden)

    Rioux Vincent

    2016-05-01

    Full Text Available Fatty acid acylation of proteins corresponds to the co- or post-translational covalent linkage of an acyl-CoA, derived from a fatty acid, to an amino-acid residue of the substrate protein. The cellular fatty acids which are involved in protein acylation are mainly saturated fatty acids. Palmitoylation (S-acylation corresponds to the reversible attachment of palmitic acid (C16:0 via a thioester bond to the side chain of a cysteine residue. N-terminal myristoylation refers to the covalent attachment of myristic acid (C14:0 by an amide bond to the N-terminal glycine of many eukaryotic and viral proteins. Octanoylation (O-acylation typically concerns the formation of an ester bond between octanoic acid (caprylic acid, C8:0 and the side chain of a serine residue of the stomach peptide ghrelin. An increasing number of proteins (enzymes, hormones, receptors, oncogenes, tumor suppressors, proteins involved in signal transduction, eukaryotic and viral structural proteins have been shown to undergo fatty acid acylation. The addition of the acyl moiety is required for the protein function and usually mediates protein subcellular localization, protein-protein interaction or protein-membrane interaction. Therefore, through the covalent modification of proteins, these saturated fatty acids exhibit emerging specific and important roles in modulating protein functions. This review provides an overview of the recent findings on the various classes of protein acylation leading to the biological ability of saturated fatty acids to regulate many pathways. Finally, the nutritional links between these elucidated biochemical mechanisms and the physiological roles of dietary saturated fatty acids are discussed.

  3. Two-color SERS microscopy for protein co-localization in prostate tissue with primary antibody-protein A/G-gold nanocluster conjugates

    Science.gov (United States)

    Salehi, Mohammad; Schneider, Lilli; Ströbel, Philipp; Marx, Alexander; Packeisen, Jens; Schlücker, Sebastian

    2014-01-01

    SERS microscopy is a novel staining technique in immunohistochemistry, which is based on antibodies labeled with functionalized noble metal colloids called SERS labels or nanotags for optical detection. Conventional covalent bioconjugation of these SERS labels cannot prevent blocking of the antigen recognition sites of the antibody. We present a rational chemical design for SERS label-antibody conjugates which addresses this issue. Highly sensitive, silica-coated gold nanoparticle clusters as SERS labels are non-covalently conjugated to primary antibodies by using the chimeric protein A/G, which selectively recognizes the Fc part of antibodies and therefore prevents blocking of the antigen recognition sites. In proof-of-concept two-color imaging experiments for the co-localization of p63 and PSA on non-neoplastic prostate tissue FFPE specimens, we demonstrate the specificity and signal brightness of these rationally designed primary antibody-protein A/G-gold nanocluster conjugates.SERS microscopy is a novel staining technique in immunohistochemistry, which is based on antibodies labeled with functionalized noble metal colloids called SERS labels or nanotags for optical detection. Conventional covalent bioconjugation of these SERS labels cannot prevent blocking of the antigen recognition sites of the antibody. We present a rational chemical design for SERS label-antibody conjugates which addresses this issue. Highly sensitive, silica-coated gold nanoparticle clusters as SERS labels are non-covalently conjugated to primary antibodies by using the chimeric protein A/G, which selectively recognizes the Fc part of antibodies and therefore prevents blocking of the antigen recognition sites. In proof-of-concept two-color imaging experiments for the co-localization of p63 and PSA on non-neoplastic prostate tissue FFPE specimens, we demonstrate the specificity and signal brightness of these rationally designed primary antibody-protein A/G-gold nanocluster conjugates

  4. Inhibition of HIV replication by pokeweed antiviral protein targeted to CD4+ cells by monoclonal antibodies

    Science.gov (United States)

    Zarling, Joyce M.; Moran, Patricia A.; Haffar, Omar; Sias, Joan; Richman, Douglas D.; Spina, Celsa A.; Myers, Dorothea E.; Kuebelbeck, Virginia; Ledbetter, Jeffrey A.; Uckun, Fatih M.

    1990-09-01

    FUNCTIONAL impairment and selective depletion of CD4+ T cells, the hallmark of AIDS, are at least partly caused by human immunodeficiency virus (HIV-1) type 1 binding to the CD4 molecule and infecting CD4+ cells1,2. It may, therefore, be of therapeutic value to target an antiviral agent to CD4+ cells to prevent infection and to inhibit HIV-1 production in patients' CD4+ cells which contain proviral DNA3,4. We report here that HIV-1 replication in normal primary CD4+ T cells can be inhibited by pokeweed antiviral protein, a plant protein of relative molecular mass 30,000 (ref. 5), which inhibits replication of certain plant RNA viruses6-8, and of herpes simplex virus, poliovirus and influenza virus9-11. Targeting pokeweed antiviral protein to CD4+ T cells by conjugating it to monoclonal antibodies reactive with CDS, CD7 or CD4 expressed on CD4+ cells, increased its anti-HIV potency up to 1,000-fold. HIV-1 replication is inhibited at picomolar concentrations of conjugates of pokeweed antiviral protein and monoclonal antibodies, which do not inhibit proliferation of normal CD4+ T cells or CD4-dependent responses. These conjugates inhibit HIV-1 protein synthesis and also strongly inhibit HIV-1 production in activated CD4+ T cells from infected patients.

  5. Manipulation of immunodominant dengue virus E protein epitopes reduces potential antibody-dependent enhancement

    Directory of Open Access Journals (Sweden)

    Hughes Holly R

    2012-06-01

    Full Text Available Abstract Background Dengue viruses (DENV are the most important arboviruses of humans and cause significant disease. Infection with DENV elicits antibody responses to the envelope glycoprotein, predominantly against immunodominant, cross-reactive, weakly-neutralizing epitopes. These weakly-neutralizing antibodies are implicated in enhancing infection via Fcγ receptor bearing cells and can lead to increased viral loads that are associated with severe disease. Here we describe results from the development and testing of cross-reactivity reduced DENV-2 DNA vaccine candidates that contain substitutions in immunodominant B cell epitopes of the fusion peptide and domain III of the envelope protein. Results Cross-reactivity reduced and wild-type vaccine candidates were similarly immunogenic in outbred mice and elicited high levels of neutralizing antibody, however mice immunized with cross-reactivity reduced vaccines produced significantly reduced levels of immunodominant cross-reactive antibodies. Sera from mice immunized with wild-type, fusion peptide-, or domain III- substitution containing vaccines enhanced heterologous DENV infection in vitro, unlike sera from mice immunized with a vaccine containing a combination of both fusion peptide and domain III substitutions. Passive transfer of immune sera from mice immunized with fusion peptide and domain III substitutions also reduced the development of severe DENV disease in AG129 mice when compared to mice receiving wild type immune sera. Conclusions Reducing cross-reactivity in the envelope glycoprotein of DENV may be an approach to improve the quality of the anti-DENV immune response.

  6. CD301b+ dendritic cells suppress T follicular helper cells and antibody responses to protein antigens

    Science.gov (United States)

    Kumamoto, Yosuke; Hirai, Toshiro; Wong, Patrick W; Kaplan, Daniel H; Iwasaki, Akiko

    2016-01-01

    Strong antibody response is considered a hallmark of a successful vaccine. While dendritic cells (DCs) are important for T follicular helper (Tfh) cell priming, how this process is regulated in vivo is unclear. We show here that the depletion of CD301b+ DCs specifically enhanced the development of Tfh cells, germinal center B cells and antibody responses against protein antigens. Exaggerated antibody responses in mice depleted of CD301b+ DCs occurred in the absence of any adjuvants, and resulting antibodies had broader specificity and higher affinity to the immunogen. CD301b+ DCs express high levels of PD-1 ligands, PD-L1 and PD-L2. Blocking PD-1 or PD-L1 during priming in wild-type mice partially mimicked the phenotype of CD301b+ DC-depleted animals, suggesting their role in Tfh suppression. Transient depletion of CD301b+ DC results in the generation of autoreactive IgG responses. These results revealed a novel regulatory mechanism and a key role of CD301b+ DCs in blocking autoantibody generation. DOI: http://dx.doi.org/10.7554/eLife.17979.001 PMID:27657168

  7. Glutamic acid decarboxylase antibody-positive paraneoplastic stiff limb syndrome associated with carcinoma of the breast

    Directory of Open Access Journals (Sweden)

    Agarwal Pankaj

    2010-01-01

    Full Text Available Stiff limb syndrome (SLS is a rare "focal" variant of stiff person syndrome which presents with rigidity and painful spasms of a distal limb, and abnormal fixed foot or hand postures. Anti-glutamic acid decarboxylase antibodies (GAD-Ab are variably present in most cases. Most reported cases of SLS are unassociated with cancer. We describe a patient with SLS as a paraneoplastic manifestation of breast carcinoma, in whom GAD-Ab was present. The patient responded very well to oral diazepam, baclofen and steroids.This is the third reported case of SLS as a paraneoplastic accompaniment to cancer.

  8. Detection of Thiobacillus ferrooxidans in acid mine environments by indirect fluorescent antibody staining.

    Science.gov (United States)

    Apel, W A; Dugan, P R; Filppi, J A; Rheins, M S

    1976-07-01

    An indirect fluorescent antibody (FA) staining technique was developed for the rapid detection of Thiobacillus ferrooxidans. The specificity of the FA stain for T. ferrooxidans was demonstrated with both laboratory and environmental samples. Coal refuse examined by scanning electron microscopy exhibited a rough, porous surface, which was characteristically covered by water-soluble crystals. Significant numbers of T. ferrooxidans were detected in the refuse pores. A positive correlation between numbers of T. ferrooxidans and acid production in coal refuse in the laboratory was demonstrated with the FA technique. PMID:61736

  9. CHARACTER OF TUMOR ASSOCIATED PROTEIN RECOGNIZED BY MONOCLONAL ANTIBODY AGAINST YUNNAN GEJIU LUNG CANCER

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objectives: To identify and characterize lung cancer associated protein N35 and attempt to learn the prospective possibility of the clinical application of the protein N35. Methods: Immunoprecipitation, immunoblotting, differential centrifigation and subcellular assay, immunohistochemistry, N-glycanase digestion, mitotic cell immunoflourescence and multiple methods of affinity chromatography have been used with the monoclonal antibody N-35 to detect the distribution of the protein N35 among the various cancer cell lines and normal human tissue, the relationship between the protein N35 and glycoprotein, the location of the subcellular structure and chromosomal domain of the protein N35,the most effective way of purification of tumor associated protein N35. Results: The protein N35 is a glycoprotein, distributes to the human lung cancer cell line GLC-82, human cervical cancer cell line Hela, human hepatic cancer cell line HepG-2 and human breast cancer cell line PMC with different relative molecular mass(Mr), but no expression of the protein ingredient in normal human fresh tissue; concentrates at the nuclei significantly ,much more than at the mitochondrail and membrane, locates at the centriole of the chromosomal domain. Conclusions: The lung cancer associated protein N35 might be expressed only by the cancer cells and related with the proliferation of cancer cells as a role of tumor cell growth regulator.

  10. Characterization of monoclonal antibodies against Muscovy duck reovirus σB protein

    Directory of Open Access Journals (Sweden)

    Shen Nan

    2010-06-01

    Full Text Available Abstract Background The σB protein of Muscovy duck reovirus (DRV, one of the major structural proteins, is able to induce neutralizing antibody in ducks, but the monoclonal antibody (MAb against σB protein has never been characterized. Results Four hybridoma cell lines secreting anti-DRV σB MAbs were obtained, designated 1E5, 2F7, 4E3 and 5D8. Immunoglobulin subclass tests differentiated them as IgG2b (1E5 and 4E3 and IgM (2F7 and 5D8. Dot blot and western blotting assays showed that MAbs reacted with His-σB protein in a conformation-independent manner. Competitive binding assay indicated that the MAbs delineated two epitopes, A and B of σB. Immunofluorescence assay indicated that the four MAbs could specifically bind to Vero cells infected with DRV and σB was distributed diffusely in the cytoplasma of infected cells. MAbs had universal reactivity to all DRVs tested in an antigen-capture enzyme-linked immunosorbent assay. Conclusion Results of this research provide important information about the four monoclonal antibodies and therefore the MAbs may be useful candidate for the development of a MAb capture ELISA for rapid detection of DRVs. In addition, it showed that the σB protein was located in the cytoplasma of infected cells by immunofluorescence assay with MAbs. Virus isolation and RT-PCR are reliable way for detection of DRV infection, but these procedures are laborious, time consuming, and requiring instruments. These obvious diagnosis problems highlight the ongoing demand of rapid, reproducible, and automatic methods for the sensitive detection of DRV.

  11. Generation of human scFvs antibodies recognizing a prion protein epitope expressed on the surface of human lymphoblastoid cells

    Directory of Open Access Journals (Sweden)

    Imperiale Valentina

    2007-07-01

    Full Text Available Abstract Background A hallmark of prion disease is the transformation of normal cellular prion protein (PrPc into an infectious disease-associated isoform, (PrPsc. Anti-prion protein monoclonal antibodies are invaluable for structure-function studies of PrP molecules. Furthermore recent in vitro and in vivo studies indicate that anti-PrP monoclonal antibodies can prevent the incorporation of PrPc into propagating prions. In the present article, we show two new human phage antibodies, isolated on recombinant hamster prion protein (rHaPrP. Results We adopted an antibody phage display strategy to isolate specific human antibodies directed towards rHaPrP which has been used as a bait for panning the synthetic ETH-2 antibody phage library. Two phage antibodies clones named MA3.B4 and MA3.G3 were isolated and characterized under genetic biochemical and immunocytochemical aspects. The clones were found to recognize the prion protein in ELISA studies. In flow-cytometry studies, these human single chain Fragment variable (scFv phage-antibodies show a well defined pattern of reactivity on human lymphoblastoid and myeloid cells. Conclusion Sequence analysis of the gene encoding for the antibody fragments and antigen recognition patterns determined by flow-cytometry analysis indicate that the isolated scFvs recognize novel epitopes in the PrPc molecule. These new anti PrPc human antibodies are unique reagents for prion protein detection and may represent a biologic platform to develop new reagents to treat PrPsc associated disease.

  12. Construction of antibody-like nanoparticles for selective protein sequestration in living cells

    Science.gov (United States)

    Liu, Yibin; Fang, Simin; Zhai, Junqiu; Zhao, Meiping

    2015-04-01

    We demonstrate the successful construction of fluorescently labeled magnetic antibody-like nanoparticles (ANPs) via a facile one-step surface-initiated in situ molecular imprinting approach over silica coated magnetite (Fe3O4@SiO2) core-shell nanocomposites. The as-prepared ANPs had a highly compact structure with an overall size of 83 +/- 5 nm in diameter and showed excellent aqueous dispersion stability. With the predetermined high specificity to the target protein and high biocompatibility, the ANPs enabled rapid, efficient, selective and optically trackable sequestration of target proteins within living cells. This work represents the first example of fully artificially engineered multifunctional ANPs for the intracellular protein-sequestration without disruption of the cells. The established approach may be further extended to generate ANPs for various proteins of interest and provide useful tools for related biological research and biomedical applications.We demonstrate the successful construction of fluorescently labeled magnetic antibody-like nanoparticles (ANPs) via a facile one-step surface-initiated in situ molecular imprinting approach over silica coated magnetite (Fe3O4@SiO2) core-shell nanocomposites. The as-prepared ANPs had a highly compact structure with an overall size of 83 +/- 5 nm in diameter and showed excellent aqueous dispersion stability. With the predetermined high specificity to the target protein and high biocompatibility, the ANPs enabled rapid, efficient, selective and optically trackable sequestration of target proteins within living cells. This work represents the first example of fully artificially engineered multifunctional ANPs for the intracellular protein-sequestration without disruption of the cells. The established approach may be further extended to generate ANPs for various proteins of interest and provide useful tools for related biological research and biomedical applications. Electronic supplementary information (ESI

  13. Prediction of protein motions from amino acid sequence and its application to protein-protein interaction

    Directory of Open Access Journals (Sweden)

    Wako Hiroshi

    2010-07-01

    Full Text Available Abstract Background Structural flexibility is an important characteristic of proteins because it is often associated with their function. The movement of a polypeptide segment in a protein can be broken down into two types of motions: internal and external ones. The former is deformation of the segment itself, but the latter involves only rotational and translational motions as a rigid body. Normal Model Analysis (NMA can derive these two motions, but its application remains limited because it necessitates the gathering of complete structural information. Results In this work, we present a novel method for predicting two kinds of protein motions in ordered structures. The prediction uses only information from the amino acid sequence. We prepared a dataset of the internal and external motions of segments in many proteins by application of NMA. Subsequently, we analyzed the relation between thermal motion assessed from X-ray crystallographic B-factor and internal/external motions calculated by NMA. Results show that attributes of amino acids related to the internal motion have different features from those related to the B-factors, although those related to the external motion are correlated strongly with the B-factors. Next, we developed a method to predict internal and external motions from amino acid sequences based on the Random Forest algorithm. The proposed method uses information associated with adjacent amino acid residues and secondary structures predicted from the amino acid sequence. The proposed method exhibited moderate correlation between predicted internal and external motions with those calculated by NMA. It has the highest prediction accuracy compared to a naïve model and three published predictors. Conclusions Finally, we applied the proposed method predicting the internal motion to a set of 20 proteins that undergo large conformational change upon protein-protein interaction. Results show significant overlaps between the

  14. Canine Antibodies against Salivary Recombinant Proteins of Phlebotomus perniciosus: A Longitudinal Study in an Endemic Focus of Canine Leishmaniasis

    OpenAIRE

    Tatiana Kostalova; Tereza Lestinova; Petra Sumova; Michaela Vlkova; Iva Rohousova; Eduardo Berriatua; Gaetano Oliva; Eleonora Fiorentino; Aldo Scalone; Marina Gramiccia; Luigi Gradoni; Petr Volf

    2015-01-01

    Background Phlebotomine sand flies are vectors of Leishmania parasites. During blood feeding, sand flies deposit into the host skin immunogenic salivary proteins which elicit specific antibody responses. These anti-saliva antibodies enable an estimate of the host exposure to sand flies and, in leishmaniasis endemic areas, also the risk for Leishmania infections. However, the use of whole salivary gland homogenates as antigen has several limitations, and therefore, recombinant salivary protein...

  15. Intumescent features of nucleic acids and proteins

    Energy Technology Data Exchange (ETDEWEB)

    Alongi, Jenny, E-mail: jenny.alongi@polito.it; Cuttica, Fabio; Blasio, Alessandro Di; Carosio, Federico; Malucelli, Giulio

    2014-09-10

    Highlights: • The combustion resistance of DNA and caseins to different heat fluxes was studied. • Upon heating, DNA and caseins exhibited an intumescent behaviour. • The char derived from DNA was more stable and coherent than that from caseins. - Abstract: Are nucleic acids and proteins intumescent molecules? In order to get an answer, in the present manuscript, powders of deoxyribose nucleic acids (DNA) and caseins have been exposed to different heat fluxes under a cone calorimeter source and to the direct application of a propane flame. Under these conditions, DNA and caseins exhibited a typical intumescent behaviour, generating a coherent expanded cellular carbonaceous residue (char), extremely resistant to heat exposure. The resulting volumetric expansion as well as the resistance of the formed char turned out to be dependent on (i) the chemical structure of the chosen biomacromolecule, (ii) the evolution of ammonia and (iii) the adopted heat flux in cone calorimetry tests (namely, 25, 35, 50 and 75 kW/m{sup 2}). The presence of ribose units within the DNA backbone determined the formation of highly expanded and coherent residues as compared to those obtained from caseins. Indeed, under a heat flux of 35 kW/m{sup 2}, when a carbon source (i.e. common cane sugar) was added to caseins, the resulting char was similar to that formed by DNA. Furthermore, the char expansion was ascribed to the evolution of ammonia released by these biomacromolecules upon heating, as detected by thermogravimetry coupled to infrared spectroscopy, and confirmed by scanning electron microscopy experiments performed on the bubbles present in the residues of flammability tests.

  16. Immunodot blot assay to detect Helicobacter pylori using monoclonal antibodies against the 26 kDa protein.

    Science.gov (United States)

    Amini Najafabadi, Hossein; Paknejad, Maliheh; Farshad, Shohreh; Mohammadian, Taher; Seyyed Ebrahimi, Shadi Sadat; Amini Najafabadi, Azadeh

    2012-12-01

    Development of a specific immunoassay to detect Helicobacter pylori infection in stool samples requires monoclonal antibody against the specific antigen. The aims of this study were to establish monoclonal antibodies against the 26 kDa protein of H. pylori and develop an immunodot blot for their application to recognize H. pylori infection using stool samples. Mice were immunized intraperitoneally with homogenized gel containing the 26 kDa band of cell surface proteins of H. pylori in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The monoclonal antibodies were produced using the hybridoma technique. Reactivity of monoclonal antibodies was tested with the purified 26 kDa antigen and cell surface proteins from cultured H. pylori by ELISA. Furthermore reactivity of monoclonal antibodies was tested on negative and positive stool samples for H. pylori and suspensions of several major bacteria in stool by immunodot blot assay. Five stable hybridoma monoclones were obtained. The concordant reactivity of the monoclonal antibodies with H. pylori present in the stool samples, which had been tested previously using an ACON ELISA kit for H. pylori stool antigen testing, and unreactivity with several different major fecal bacteria in immunodot blotting indicates high specificity of the immunodot blot based on the reaction of produced monoclonal antibodies with the H. pylori antigen in stools. The findings indicate that the novel immunodot blot developed based on new monoclonal antibodies for stool antigens would be useful as a noninvasive method of diagnosing H. pylori infection. PMID:23244318

  17. Production and Application of Polyclonal Antibodies Against Recombinant Capsid Protein of Extra Small Virus of Macrobrachium rosenbergii.

    Science.gov (United States)

    Neethi, V; Sivakumar, N; Kumar, Kundan; Rajendran, K V; Makesh, M

    2012-12-01

    Macrobrachium rosenbergii nodavirus along with a satellite virus, extra small virus (XSV) causes white tail disease (WTD) in the giant freshwater prawn M. rosenbergii. Infected M. rosenbergii postlarvae were collected from a hatchery in Kakinada, Andhra Pradesh. The gene coding the capsid protein of XSV was cloned in a bacterial expression vector pRSET A and the recombinant protein was expressed in Escherichia coli BL21(DE3)pLysS cells. The recombinant protein was purified by Nickel affinity chromatography. Polyclonal antibodies were produced in mice against the recombinant protein and the antibodies reacted specifically with the recombinant protein and XSV in WTD-infected tissues. This is the first report of detection of XSV using antibodies against recombinant capsid protein.

  18. Anti-Yo and anti-glutamic acid decarboxylase antibodies presenting in carcinoma of the uterus with paraneoplastic cerebellar degeneration: a case report

    Directory of Open Access Journals (Sweden)

    Panegyres Peter K

    2012-06-01

    Full Text Available Abstract Introduction Paraneoplastic cerebellar degeneration is a rare non-metastatic manifestation of malignancy. In this report, to the best of our knowledge we describe for the first time a diagnosis of paraneoplastic cerebellar degeneration several months prior to the diagnosis of clear carcinoma of the uterus. Case presentation A 75-year-old Caucasian woman manifested a rapidly progressive cerebellar syndrome with nystagmus, past-pointing, dysdiadochokinesis, dysarthria, truncal ataxia and titubation. The paraneoplastic cerebellar degeneration was associated with anti-Yo and anti-glutamic acid decarboxylase antibodies. 14-3-3 protein was detected in the cerebrospinal fluid. She was treated with intravenous immunoglobulin prior to laparotomy, hysterectomy and bilateral salpingoophorectomy. Our patient has survived for three years following diagnosis and treatment. Conclusions To the best of our knowledge this is the first report of an association of clear cell carcinoma of the uterus and paraneoplastic cerebellar degeneration with both anti-Yo and anti-glutamic acid decarboxylase antibodies. The findings imply that both antibodies contributed to the fulminating paraneoplastic cerebellar degeneration observed in our patient, and this was of such severity it resulted in the release of 14-3-3 protein in the cerebrospinal fluid, a marker of neuronal death.

  19. Full validation of therapeutic antibody sequences by middle-up mass measurements and middle-down protein sequencing.

    Science.gov (United States)

    Resemann, Anja; Jabs, Wolfgang; Wiechmann, Anja; Wagner, Elsa; Colas, Olivier; Evers, Waltraud; Belau, Eckhard; Vorwerg, Lars; Evans, Catherine; Beck, Alain; Suckau, Detlev

    2016-01-01

    The regulatory bodies request full sequence data assessment both for innovator and biosimilar monoclonal antibodies (mAbs). Full sequence coverage is typically used to verify the integrity of the analytical data obtained following the combination of multiple LC-MS/MS datasets from orthogonal protease digests (so called "bottom-up" approaches). Top-down or middle-down mass spectrometric approaches have the potential to minimize artifacts, reduce overall analysis time and provide orthogonality to this traditional approach. In this work we report a new combined approach involving middle-up LC-QTOF and middle-down LC-MALDI in-source decay (ISD) mass spectrometry. This was applied to cetuximab, panitumumab and natalizumab, selected as representative US Food and Drug Administration- and European Medicines Agency-approved mAbs. The goal was to unambiguously confirm their reference sequences and examine the general applicability of this approach. Furthermore, a new measure for assessing the integrity and validity of results from middle-down approaches is introduced - the "Sequence Validation Percentage." Full sequence data assessment of the 3 antibodies was achieved enabling all 3 sequences to be fully validated by a combination of middle-up molecular weight determination and middle-down protein sequencing. Three errors in the reference amino acid sequence of natalizumab, causing a cumulative mass shift of only -2 Da in the natalizumab Fd domain, were corrected as a result of this work.

  20. Antibody reactivity to conserved linear epitopes of Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1)

    DEFF Research Database (Denmark)

    Staalsø, T; Khalil, E A; Elhassan, I M;

    1998-01-01

    The Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family of protein antigens are involved in adhesion of P. falciparum infected erythrocytes to the capillary endothelium of the host. Antibodies to variable regions of these proteins, measured by agglutination, correlates with clini......The Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family of protein antigens are involved in adhesion of P. falciparum infected erythrocytes to the capillary endothelium of the host. Antibodies to variable regions of these proteins, measured by agglutination, correlates...... synthetic peptides derived from conserved regions of PfEMP1. The antibody responses to these peptides increased with age and were higher in individuals with asymptomatic P. falciparum infection compared to individuals presenting with fever attributable to falciparum malaria. This indicates that antibodies...... recognising the conserved regions of PfEMP1 arise upon exposure to the parasite, and that these may be involved in the development of protection against malaria. Antibodies to the Pfalhesin peptide of the human aniontransporter, band3, were measured by the same method. The magnitude of this antibody response...

  1. The clonal antibody response to Pseudomonas aeruginosa heat shock protein is highly diverse in cystic fibrosis patients

    DEFF Research Database (Denmark)

    Ulanova, M; Petersen, T D; Ciofu, O;

    1997-01-01

    The GroEL protein of Pseudomonas aeruginosa belongs to the bacterial 60-65 kDa heat shock protein family. A strong antibody response to GroEL has been found in cystic fibrosis (CF) patients with chronic pulmonary infection caused by P. aeruginosa. Clonotypes of IgG1 and IgG2 antibodies against Gro...... antibody clones against GroEL. The appearance of new clones with time reflected the long duration of the chronic infection. A striking addition of new clonotypes during the observation period occurred when a new unrelated bacterium (Burkholderia cepacia) had become established as a cause of the pulmonary...

  2. Seroreactive marker for inflammatory bowel disease and associations with antibodies to dietary proteins in bipolar disorder

    Science.gov (United States)

    Severance, Emily G.; Gressitt, Kristin L.; Yang, Shuojia; Stallings, Cassie R.; Origoni, Andrea E.; Vaughan, Crystal; Khushalani, Sunil; Alaedini, Armin; Dickerson, Faith B.; Yolken, Robert H.

    2014-01-01

    Objectives Immune sensitivity to wheat glutens and bovine milk caseins may affect a subset of individuals with bipolar disorder. Digested byproducts of these foods are exorphins that have the potential to impact brain physiology through action at opioid receptors. Inflammation in the gastrointestinal (GI) tract might accelerate exposure of food antigens to systemic circulation and help explain elevated gluten and casein antibody levels in individuals with bipolar disorder. Methods We measured a marker of GI inflammation, anti-Saccharomyces cerevisiae antibodies (ASCA), in non-psychiatric controls (n=207), bipolar disorder without a recent onset of psychosis (n=226), and bipolar disorder with a recent onset of psychosis (n=38). We compared ASCA levels to antibodies against gluten, casein, EBV, HSV-1, Influenza A, Influenza B, measles, and Toxoplasma gondii. Results Elevated ASCA conferred a 3.5 to 4.4-fold increased odds ratio of disease association (age-, race- and gender-corrected multinomial logistic regressions, p≤0.00001) that was independent of type of medication received. ASCA correlated with food antibodies in both bipolar groups (R2=0.29–0.59, p≤0.0005), and with measles and T. gondii IgG in the recent onset psychosis bipolar disorder group (R2=0.31–0.36, p≤0.004–0.01). Conclusions Elevated seropositivity of a GI-related marker and its association with antibodies to food-derived proteins and self-reported GI symptoms suggests a GI comorbidity in at least a subgroup of individuals with bipolar disorder. Marker seroreactivity may also represent part of an overall heightened activated immune state inherent to this mood disorder. PMID:24313887

  3. Fusion Proteins Cpn10-Erns with Properties of Generating CSFV-Neutralized Antibodies

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    When pigs are infected with classical swine fever virus (CSFV), the antibody primarily targets the structural glycoprotein E rns of the virus. Previous investigations have demonstrated that E rns has low or no virus neutralizing capacity. In this study, candidate subunit marker vaccine, chaperonin 10(Cpn10)-Erns, which possess the property of generating neutralized antibodies against lethal challenge of virulent CSFV was developed. The gene of E rns was isolated from Hog cholera lapinized virus (HCLV)-infected spleen cells of rabbits via RT-PCR method and fused to the downstream region of the cpn10 gene; the products of recombinant fusion protein (cpn10-Erns) induced expression in Escherichia coli, and the products were purified by affinity chromatography. During the course of vaccination, the candidate vaccines cpn10-E rns were used for the immunization of guinea pigs, and they induced a strong antibody response against cpn10-Erns. The antibodies can be immobilized by coating inactivated CSFV particles, indicating that these antibodies can recognize CSFV. Neutralization assay was carried out on rabbits according to National Regulations on Veterinary Drug. The results clearly indicate that the typical fever of rabbits induced by the live attenuated HCLV could be inhibited by preincubation with the antisera (dilution 1:4) induced by cpn10-Erns, but not inhibited by preincubation with the antisera induced only by Erns. Analogous results were observed for the group of the rabbits immunized with cpn10-Erns, which were protected against the typical fever induced by the challenge with HCLV. The findings of this study formed the basis of a new means for developing subunit marker vaccine against CSFV.

  4. Fermentanomics informed amino acid supplementation of an antibody producing mammalian cell culture.

    Science.gov (United States)

    Read, Erik K; Bradley, Scott A; Smitka, Tim A; Agarabi, Cyrus D; Lute, Scott C; Brorson, Kurt A

    2013-01-01

    Fermentanomics, or a global understanding of a culture state on the molecular level empowered by advanced techniques like NMR, was employed to show that a model hybridoma culture supplied with glutamine and glucose depletes aspartate, cysteine, methionine, tryptophan, and tyrosine during antibody production. Supplementation with these amino acids prevents depletion and improves culture performance. Furthermore, no significant changes were observed in the distribution of glycans attached to the IgG3 in cultures supplemented with specific amino acids, arguing that this strategy can be implemented without fear of impact on important product quality attributes. In summary, a targeted strategy of quantifying media components and designing a supplementation strategy can improve bioprocess cell cultures when enpowered by fermentanomics tools.

  5. Antibody-independent Targeted Quantification of TMPRSS2-ERG Fusion Protein Products in Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    He, Jintang; Sun, Xuefei; Shi, Tujin; Schepmoes, Athena A.; Fillmore, Thomas L.; Petyuk, Vladislav A.; Xie, Fang; Zhao, Rui; Gritsenko, Marina A.; Yang, Feng; Kitabayashi, Naoki; Chae, Sung Suk; Rubin, Mark; Siddiqui, Javed; Wei, John; Chinnaiyan, Arul M.; Qian, Weijun; Smith, Richard D.; Kagan, Jacob; Srivastava, Sudhir; Rodland, Karin D.; Liu, Tao; Camp, David G.

    2014-10-01

    Fusions between the transmembrane protease serine 2 (TMPRSS2) and ETS related gene (ERG) represent one of the most specific biomarkers that define a distinct molecular subtype of prostate cancer. The studies on TMPRSS2-ERG gene fusions have seldom been performed at the protein level, primarily due to the lack of high-quality antibodies or an antibody-independent method that is sufficiently sensitive for detecting the truncated ERG protein products resulting from TMPRSS2-ERG gene fusions and alternative splicing. Herein, we applied a recently developed PRISM (high-pressure high-resolution separations with intelligent selection and multiplexing)-SRM (selected reaction monitoring) strategy for quantifying ERG protein in prostate cancer cell lines and tumors. The highly sensitive PRISM-SRM assays led to confident detection of 6 unique ERG peptides in either the TMPRSS2-ERG positive cell lines or tissues but not in the negative controls, indicating that ERG protein expression is highly correlated with TMPRSS2-ERG gene rearrangements. Significantly, our results demonstrated for the first time that at least two groups of ERG protein isoforms were simultaneously expressed at variable levels in TMPRSS2-ERG positive samples as evidenced by concomitant detection of two mutually exclusive peptides. Three peptides shared across almost all fusion protein products were determined to be the most abundant peptides, and hence can be used as “signature” peptides for detecting ERG overexpression resulting from TMPRSS2-ERG gene fusion. These PRISM-SRM assays provide valuable tools for studying TMPRSS2-ERG gene fusion protein products, thus improving our understanding of the role of TMPRSS2-ERG gene fusion in the biology of prostate cancer.

  6. Engineering the vaccinia virus L1 protein for increased neutralizing antibody response after DNA immunization

    Directory of Open Access Journals (Sweden)

    Moss Bernard

    2009-03-01

    Full Text Available Abstract Background The licensed smallpox vaccine, comprised of infectious vaccinia virus, has associated adverse effects, particularly for immunocompromised individuals. Therefore, safer DNA and protein vaccines are being investigated. The L1 protein, a component of the mature virion membrane that is conserved in all sequenced poxviruses, is required for vaccinia virus entry into host cells and is a target for neutralizing antibody. When expressed by vaccinia virus, the unglycosylated, myristoylated L1 protein attaches to the viral membrane via a C-terminal transmembrane anchor without traversing the secretory pathway. The purpose of the present study was to investigate modifications of the gene expressing the L1 protein that would increase immunogenicity in mice when delivered by a gene gun. Results The L1 gene was codon modified for optimal expression in mammalian cells and potential N-glycosylation sites removed. Addition of a signal sequence to the N-terminus of L1 increased cell surface expression as shown by confocal microscopy and flow cytometry of transfected cells. Removal of the transmembrane domain led to secretion of L1 into the medium. Induction of binding and neutralizing antibodies in mice was enhanced by gene gun delivery of L1 containing the signal sequence with or without the transmembrane domain. Each L1 construct partially protected mice against weight loss caused by intranasal administration of vaccinia virus. Conclusion Modifications of the vaccinia virus L1 gene including codon optimization and addition of a signal sequence with or without deletion of the transmembrane domain can enhance the neutralizing antibody response of a DNA vaccine.

  7. Synthesis and electrochemical characterization of myoglobin-antibody protein immobilized self-assembled gold nanoparticles on ITO-glass plate

    Energy Technology Data Exchange (ETDEWEB)

    Rajesh, E-mail: rajesh_csir@yahoo.com [Polymer and Soft Material Section, National Physical Laboratory (Council of Scientific and Industrial Research), Dr. K.S. Krishnan Road, New Delhi 110012 (India); Sharma, Vikash; Mishra, Sujeet K.; Biradar, Ashok M. [Polymer and Soft Material Section, National Physical Laboratory (Council of Scientific and Industrial Research), Dr. K.S. Krishnan Road, New Delhi 110012 (India)

    2012-01-16

    Highlights: Black-Right-Pointing-Pointer The Mb-Ab was covalently bonded to carboxyl groups of the mixed MUA and MPA over self-assembled GNPs. Black-Right-Pointing-Pointer This assembly on ITO-glass plate was used as an impedimetric immunosensor for myoglobin detection. Black-Right-Pointing-Pointer High loading of Mb-Ab, on the GNPs results in a wide range of Mb-Ag detection from 0.01 {mu}g to 1.65 {mu}g mL{sup -1} Black-Right-Pointing-Pointer The simple method and wide range of Mb-Ag detection makes this advantageous over other methods. - Abstract: We report a protein immobilized self-assembled monolayer (SAM) of gold nanoparticles (GNPs) on indium-tin-oxide (ITO) coated glass plate. The protein-antibody, Mb-Ab, was covalently immobilized over the self-assembly of GNPs through a mixed SAM of 11-mercapto undecanoic acid (MUA) and 3-mercapto propionic acid (MPA) via carbodiimide coupling reaction using N-(3-dimethylaminopropyl)-N Prime -ethyl carbodiimide (EDC) and N-hydroxy succinimide (NHS). The whole assembly was constructed on 0.25 cm{sup 2} area of ITO-glass plate (Mb-Ab/MUA-MPA/GNPs/APTES/ITO-glass) and an impedimetric study was carried out for its application in myoglobin detection. This prototype assembly was characterized by scanning electron microscopy, atomic force microscopy and electrochemical techniques. The modified electrode showed an increased electron-transfer resistance on coupling with protein antigen, Mb-Ag, in the presence of a redox probe [Fe(CN){sub 6}]{sup 3-/4-}. Its exhibits an electrochemical impedance response to protein myoglobin-antigen, Mb-Ag, concentration in a linear range from 0.01 {mu}g to 1.65 {mu}g mL{sup -1} with a lowest detection limit of 1.4 ng mL{sup -1}.

  8. Synthesis and electrochemical characterization of myoglobin-antibody protein immobilized self-assembled gold nanoparticles on ITO-glass plate

    International Nuclear Information System (INIS)

    Highlights: ► The Mb-Ab was covalently bonded to carboxyl groups of the mixed MUA and MPA over self-assembled GNPs. ► This assembly on ITO-glass plate was used as an impedimetric immunosensor for myoglobin detection. ► High loading of Mb-Ab, on the GNPs results in a wide range of Mb-Ag detection from 0.01 μg to 1.65 μg mL−1 ► The simple method and wide range of Mb-Ag detection makes this advantageous over other methods. - Abstract: We report a protein immobilized self-assembled monolayer (SAM) of gold nanoparticles (GNPs) on indium-tin-oxide (ITO) coated glass plate. The protein-antibody, Mb-Ab, was covalently immobilized over the self-assembly of GNPs through a mixed SAM of 11-mercapto undecanoic acid (MUA) and 3-mercapto propionic acid (MPA) via carbodiimide coupling reaction using N-(3-dimethylaminopropyl)-N′-ethyl carbodiimide (EDC) and N-hydroxy succinimide (NHS). The whole assembly was constructed on 0.25 cm2 area of ITO-glass plate (Mb-Ab/MUA-MPA/GNPs/APTES/ITO-glass) and an impedimetric study was carried out for its application in myoglobin detection. This prototype assembly was characterized by scanning electron microscopy, atomic force microscopy and electrochemical techniques. The modified electrode showed an increased electron-transfer resistance on coupling with protein antigen, Mb-Ag, in the presence of a redox probe [Fe(CN)6]3−/4−. Its exhibits an electrochemical impedance response to protein myoglobin-antigen, Mb-Ag, concentration in a linear range from 0.01 μg to 1.65 μg mL−1 with a lowest detection limit of 1.4 ng mL−1.

  9. Detection of antibodies against porcine parvovirus nonstructural protein NS1 may distinguish between vaccinated and infected pigs

    DEFF Research Database (Denmark)

    Madsen, Eva Smedegaard; Madsen, Knud Gert; Nielsen, Jens;

    1997-01-01

    The humoral antibody response against the nonstructural protein NS1 and the structural protein VP2 of porcine parvovirus (PPV) was evaluated by immuno-peroxidase test (IPT) and enzyme linked immune sorbent assay (ELISA) using recombinant PPV antigens. The coding sequence for NS1 and VP2 was inser......The humoral antibody response against the nonstructural protein NS1 and the structural protein VP2 of porcine parvovirus (PPV) was evaluated by immuno-peroxidase test (IPT) and enzyme linked immune sorbent assay (ELISA) using recombinant PPV antigens. The coding sequence for NS1 and VP2...

  10. Echinococcus granulosus fatty acid binding proteins subcellular localization.

    Science.gov (United States)

    Alvite, Gabriela; Esteves, Adriana

    2016-05-01

    Two fatty acid binding proteins, EgFABP1 and EgFABP2, were isolated from the parasitic platyhelminth Echinococcus granulosus. These proteins bind fatty acids and have particular relevance in flatworms since de novo fatty acids synthesis is absent. Therefore platyhelminthes depend on the capture and intracellular distribution of host's lipids and fatty acid binding proteins could participate in lipid distribution. To elucidate EgFABP's roles, we investigated their intracellular distribution in the larval stage by a proteomic approach. Our results demonstrated the presence of EgFABP1 isoforms in cytosolic, nuclear, mitochondrial and microsomal fractions, suggesting that these molecules could be involved in several cellular processes.

  11. Antibody Responses in Patients with Staphylococcal Septicemia against Two Staphylococcus aureus Fibrinogen Binding Proteins: Clumping Factor and an Extracellular Fibrinogen Binding Protein

    OpenAIRE

    Colque-Navarro, Patricia; Palma, Marco; Söderquist, Bo; Flock, Jan-Ingmar; Möllby, Roland

    2000-01-01

    We analyzed the serum antibody responses against two Staphylococcus aureus fibrinogen binding proteins, the cell-bound clumping factor (Clf) and an extracellular fibrinogen binding protein (Efb). The material consisted of 105 consecutive serum samples from 41 patients suffering from S. aureus septicemia and 72 serum samples from healthy individuals. An enzyme-linked immunosorbent assay (ELISA) was developed. Healthy individuals showed variable levels of antibodies against the studied antigens...

  12. Biosimilar structural comparability assessment by NMR: from small proteins to monoclonal antibodies

    Science.gov (United States)

    Japelj, Boštjan; Ilc, Gregor; Marušič, Jaka; Senčar, Jure; Kuzman, Drago; Plavec, Janez

    2016-08-01

    Biosimilar drug products must have a demonstrated similarity with respect to the reference product’s molecules in order to ensure both the effectiveness of the drug and the patients’ safety. In this paper the fusion framework of a highly sensitive NMR fingerprinting approach for conformational changes and mathematically-based biosimilarity metrics is introduced. The final goal is to translate the complex spectral information into biosimilarity scores, which are then used to estimate the degree of similarity between the biosimilar and the reference product. The proposed method was successfully applied to a small protein, i.e., filgrastim (neutropenia treatment), which is the first biosimilar approved in the United States, and a relatively large protein, i.e., monoclonal antibody rituximab (lymphoma treatment). This innovative approach introduces a new level of sensitivity to structural changes that are induced by, e.g., a small pH shift or other changes in the protein formulation.

  13. Overcoming antigen masking of anti-amyloidbeta antibodies reveals breaking of B cell tolerance by virus-like particles in amyloidbeta immunized amyloid precursor protein transgenic mice

    Directory of Open Access Journals (Sweden)

    Ugen Kenneth E

    2004-06-01

    Full Text Available Abstract Background In prior work we detected reduced anti-Aβ antibody titers in Aβ-vaccinated transgenic mice expressing the human amyloid precursor protein (APP compared to nontransgenic littermates. We investigated this observation further by vaccinating APP and nontransgenic mice with either the wild-type human Aβ peptide, an Aβ peptide containing the "Dutch Mutation", E22Q, or a wild-type Aβ peptide conjugated to papillomavirus virus-like particles (VLPs. Results Anti-Aβ antibody titers were lower in vaccinated APP than nontransgenic mice even when vaccinated with the highly immunogenic Aβ E22Q. One concern was that human Aβ derived from the APP transgene might mask anti-Aβ antibodies in APP mice. To test this possibility, we dissociated antigen-antibody complexes by incubation at low pH. The low pH incubation increased the anti-Aβ antibody titers 20–40 fold in APP mice but had no effect in sera from nontransgenic mice. However, even after dissociation, the anti-Aβ titers were still lower in transgenic mice vaccinated with wild-type Aβ or E22Q Aβ relative to non-transgenic mice. Importantly, the dissociated anti-Aβ titers were equivalent in nontransgenic and APP mice after VLP-based vaccination. Control experiments demonstrated that after acid-dissociation, the increased antibody titer did not cross react with bovine serum albumin nor alpha-synuclein, and addition of Aβ back to the dissociated serum blocked the increase in antibody titers. Conclusions Circulating human Aβ can interfere with ELISA assay measurements of anti-Aβ titers. The E22Q Aβ peptide vaccine is more immunogenic than the wild-type peptide. Unlike peptide vaccines, VLP-based vaccines against Aβ abrogate the effects of Aβ self-tolerance.

  14. Mutagenic roles of DNA "repair" proteins in antibody diversity and disease-associated trinucleotide repeat instability.

    Science.gov (United States)

    Slean, Meghan M; Panigrahi, Gagan B; Ranum, Laura P; Pearson, Christopher E

    2008-07-01

    While DNA repair proteins are generally thought to maintain the integrity of the whole genome by correctly repairing mutagenic DNA intermediates, there are cases where DNA "repair" proteins are involved in causing mutations instead. For instance, somatic hypermutation (SHM) and class switch recombination (CSR) require the contribution of various DNA repair proteins, including UNG, MSH2 and MSH6 to mutate certain regions of immunoglobulin genes in order to generate antibodies of increased antigen affinity and altered effector functions. Another instance where "repair" proteins drive mutations is the instability of gene-specific trinucleotide repeats (TNR), the causative mutations of numerous diseases including Fragile X mental retardation syndrome (FRAXA), Huntington's disease (HD), myotonic dystrophy (DM1) and several spinocerebellar ataxias (SCAs) all of which arise via various modes of pathogenesis. These healthy and deleterious mutations that are induced by repair proteins are distinct from the genome-wide mutations that arise in the absence of repair proteins: they occur at specific loci, are sensitive to cis-elements (sequence context and/or epigenetic marks) and transcription, occur in specific tissues during distinct developmental windows, and are age-dependent. Here we review and compare the mutagenic role of DNA "repair" proteins in the processes of SHM, CSR and TNR instability.

  15. A comparison of protein A chromatographic stationary phases: performance characteristics for monoclonal antibody purification.

    Science.gov (United States)

    Liu, Zhuo; Mostafa, Sigma S; Shukla, Abhinav A

    2015-01-01

    Protein A chromatography remains the dominant capture step used during the downstream purification of monoclonal antibodies (mAbs). With the recent expiry of the Repligen patent on recombinant Protein A, a variety of new Protein A resins have been introduced in the market. Given productivity limitations during downstream processing that have come into sharper focus with the recent increase in cell culture titers for mAbs, the selection of an appropriate Protein A resin has direct implications on the overall process economics of mAb production. The performance of seven different Protein A chromatographic resins was compared with respect to static binding capacity and dynamic binding capacity as a function of flow rate. This data was translated into a comparison of productivity (g mAb purified per unit resin volume per unit time) for the seven stationary phases. In addition, elution pH and host cell protein impurity levels after product capture on each of these resins were determined. The current article provides an effective methodology and dataset for the selection of the optimal Protein A chromatographic resin. PMID:24823474

  16. A broad set of different llama antibodies specific for a 16 kDa heat shock protein of Mycobacterium tuberculosis.

    Directory of Open Access Journals (Sweden)

    Anke K Trilling

    Full Text Available BACKGROUND: Recombinant antibodies are powerful tools in engineering of novel diagnostics. Due to the small size and stable nature of llama antibody domains selected antibodies can serve as a detection reagent in multiplexed and sensitive assays for M. tuberculosis. METHODOLOGY/PRINCIPAL FINDINGS: Antibodies for Mycobacterium tuberculosis (M. tb recognition were raised in Alpaca, and, by phage display, recombinant variable domains of heavy-chain antibodies (VHH binding to M. tuberculosis antigens were isolated. Two phage display selection strategies were followed: one direct selection using semi-purified protein antigen, and a depletion strategy with lysates, aiming to avoid cross-reaction to other mycobacteria. Both panning methods selected a set of binders with widely differing complementarity determining regions. Selected recombinant VHHs were produced in E. coli and shown to bind immobilized lysate in direct Enzymelinked Immunosorbent Assay (ELISA tests and soluble antigen by surface plasmon resonance (SPR analysis. All tested VHHs were specific for tuberculosis-causing mycobacteria (M. tuberculosis, M. bovis and exclusively recognized an immunodominant 16 kDa heat shock protein (hsp. The highest affinity VHH had a dissociation constant (KD of 4 × 10(-10 M. CONCLUSIONS/SIGNIFICANCE: A broad set of different llama antibodies specific for 16 kDa heat shock protein of M. tuberculosis is available. This protein is highly stable and abundant in M. tuberculosis. The VHH that detect this protein are applied in a robust SPR sensor for identification of tuberculosis-causing mycobacteria.

  17. Solution Structure and Backbone Dynamics of Human Liver Fatty Acid Binding Protein: Fatty Acid Binding Revisited

    OpenAIRE

    Cai, Jun; Lücke, Christian; Chen, Zhongjing; Qiao, Ye; Klimtchuk, Elena; Hamilton, James A.

    2012-01-01

    Liver fatty acid binding protein (L-FABP), a cytosolic protein most abundant in liver, is associated with intracellular transport of fatty acids, nuclear signaling, and regulation of intracellular lipolysis. Among the members of the intracellular lipid binding protein family, L-FABP is of particular interest as it can i), bind two fatty acid molecules simultaneously and ii), accommodate a variety of bulkier physiological ligands such as bilirubin and fatty acyl CoA. To better understand the p...

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

    Directory of Open Access Journals (Sweden)

    Nicole J Moreland

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

  19. Preparation of Monoclonal Antibodies Against Prion Proteins With Full-length Hamster PrP

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Objective To prepare the PrP specific monoclonal antibodies (mAbs) that can be used for the detection of mammalian prions and study of pathogenesis of prion diseases. Methods Several BALB/c mice were immunized with recombinant hamster prion protein (HaPrP). Three hybridoma cell lines designated as B7, B9, and B10, secreting monoclonal antibodies against HaPrP, were established by hybridoma technique. The mAbs reactivities were evaluated with ELISA, Western blot, and immunohistochemistry. Results The mAbs produced by these cell lines reacted well with different recombinant hamster PrP proteins. Western blot analyses showed that mAbs B7 and B9 reacted with PrPSc from the scrapie-infected animals after proteinase K digestion with three glycosylated forms. The mAbs exhibited cross-reactivity with various PrPC from several other mammalian species, including humans and cattles. Immunohistochemistry assays confirmed that mAbs B7 and B9 could recognize not only extracellular but also intracellular PrPSc. Conclusion The mAbs of prion protein are successfully generated by hybridoma technique and can be applied for the diagnosis of prion associated diseases.

  20. Amino acid sequences of proteins from Leptospira serovar pomona

    Directory of Open Access Journals (Sweden)

    Alves Selmo F

    2000-01-01

    Full Text Available This report describes a partial amino acid sequences from three putative outer envelope proteins from Leptospira serovar pomona. In order to obtain internal fragments for protein sequencing, enzymatic and chemical digestion was performed. The enzyme clostripain was used to digest the proteins 32 and 45 kDa. In situ digestion of 40 kDa molecular weight protein was accomplished using cyanogen bromide. The 32 kDa protein generated two fragments, one of 21 kDa and another of 10 kDa that yielded five residues. A fragment of 24 kDa that yielded nineteen residues of amino acids was obtained from 45 kDa protein. A fragment with a molecular weight of 20 kDa, yielding a twenty amino acids sequence from the 40 kDa protein.

  1. A role for plasma cell targeting agents in immune tolerance induction in autoimmune disease and antibody responses to therapeutic proteins.

    Science.gov (United States)

    Rosenberg, A S; Pariser, A R; Diamond, B; Yao, L; Turka, L A; Lacana, E; Kishnani, P S

    2016-04-01

    Antibody responses to life saving therapeutic protein products, such as enzyme replacement therapies (ERT) in the setting of lysosomal storage diseases, have nullified product efficacy and caused clinical deterioration and death despite treatment with immune-suppressive therapies. Moreover, in some autoimmune diseases, pathology is mediated by a robust antibody response to endogenous proteins such as is the case in pulmonary alveolar proteinosis, mediated by antibodies to Granulocyte Macrophage-Colony Stimulating Factor (GM-CSF). In this work, we make the case that in such settings, when the antibody response is high titered, sustained, and refractory to immune suppressive treatments, the antibody response is mediated by long-lived plasma cells which are relatively unperturbed by immune suppressants including rituximab. However, long-lived plasma cells can be targeted by proteasome inhibitors such as bortezomib. Recent reports of successful reversal of antibody responses with bortezomib in the settings of ERT and Thrombotic Thrombocytopenic Purpura (TTP) argue that the safety and efficacy of such plasma cell targeting agents should be evaluated in larger scale clinical trials to delineate the risks and benefits of such therapies in the settings of antibody-mediated adverse effects to therapeutic proteins and autoantibody mediated pathology. PMID:26928739

  2. Immunoglobulin M and G antibody responses to Plasmodium falciparum glutamate-rich protein

    DEFF Research Database (Denmark)

    Dziegiel, Morten Hanefeld; Rowe, P; Bennett, S;

    1993-01-01

    The aims of the present study were to describe the age-related immunoglobulin M (IgM) and IgG response to part of a 220-kDa glutamate-rich protein (GLURP) from Plasmodium falciparum and to determine possible correlations of possession of these antibodies with malaria morbidity. IgM and IgG levels...... in May and in October. Seropositivity rates increased with age to a maximum of 77% for IgM and 95% for IgG in adults. High prevalences of seropositivity were associated with certain human leukocyte antigen class II alleles (DRw8, DR9, DR7, DR4, DQw7, and DQw2) or haplotypes. The relationship between anti......-GLURP489-1271 antibodies and clinical immunity is not clear; asymptomatically infected children aged 5 to 8 years had significantly higher levels of IgG than clinically ill children of the same age, suggesting that antibodies to the carboxy-terminal part of the GLURP may contribute to immunity to P...

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

    Directory of Open Access Journals (Sweden)

    Corina Wilding

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

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

    Science.gov (United States)

    Wilding, Corina; Bell, Katharina; Beck, Sabine; Funke, Sebastian; Pfeiffer, Norbert; Grus, Franz H

    2014-01-01

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

  5. Monoclonal Antibody Production and Immunolocalization of a Salinity Stress-Related Protein in Rice (Oryza sativa)

    Institute of Scientific and Technical Information of China (English)

    Jackson MARCONDES; Ana Beatriz GARCIA

    2011-01-01

    Among various physiological responses to salt stress,the synthesis of a lectin-related protein of 14.5 kDa was observed in rice plants (Oryza sativa L.) under the treatment of 170 mmol/L NaCl.In order to better understand the role of the SALT protein in the physiological processes involving salinity,it was immunolocalized in mesophilic cells of leaf sheath and blade of a rice variety IAC-4440 following monoclonal antibodies produced by hybridome culture technique.This variety turned out to be an excellent model for that purpose,since it accumulates SALT protein even in absence of salt treatment and it has been classified as moderately sensitive to salinity and a superior grain producer.This feature was relevant for this work since it allowed the use of plants without the deleterious effects caused by salinity.Immunocytochemistry assays revealed that the SALT protein is located in the stroma of chloroplasts under non-stressing condition.Since the chloroplast is the main target affected by salinity and considering that the SALT protein does not present any apparent signal peptide for organelle localization,its lectin-like activity seems to play an important role in the establishment of stable complexes,either to other proteins or to oligosaccharides that are translocated to the chloroplast.

  6. Combination of neutralizing monoclonal antibodies against Hepatitis C virus E2 protein effectively blocks virus infection.

    Science.gov (United States)

    Bose, Mihika; Mullick, Ranajoy; Das, Soma; Das, Saumitra; Karande, Anjali A

    2016-09-15

    Hepatitis C virus (HCV) represents a major global health threat. The envelope glycoproteins, E1-E2 of HCV play an important role in infection by binding to hepatocyte surface receptors leading to viral entry. Several regions on the E1-E2 are conserved for maintaining structural stability, despite the high mutation rate of HCV. Identification of antigenic determinants in these domains would aid in the development of anti-virals. The present study was aimed to delineate neutralizing epitopes by generating monoclonal antibodies (mAbs) to envelope proteins that can block virus binding and entry. Using HCV-like particles (HCV-LPs) corresponding to genotype 3a (prevalent in India), we obtained three mAbs specific for the E2 protein that significantly inhibited virus binding to hepatoma cells. Using overlapping protein fragments and peptides of the E2 protein, the epitopes corresponding to the mAbs were delineated. MAbs H6D3 and A10F2 recognise sequential linear epitopes, whereas, mAb E3D8 recognises a discontinuous epitope. The epitope of mAb E3D8 overlaps with the CD81 receptor-binding site and that of mAb A10F2 with the hypervariable region 2 of the E2 protein. The epitopes corresponding to these mAbs are distinct and unique. A combination of these antibodies significantly inhibited HCV binding and entry in both HCV pseudoparticle (in vitro) and HCV cell culture (ex vivo) system compared to the mAbs alone (P<0.0001). In conclusion, our findings support the potential of employing a cocktail of neutralizing mAbs in the management of HCV infection. PMID:27574733

  7. Eradication of Human Hepatic and Pulmonary Melanoma Metastases in SCID Mice by Antibody--Interleukin 2 Fusion Proteins

    Science.gov (United States)

    Becker, Jurgen C.; Pancook, James D.; Gillies, Stephen D.; Mendelsohn, John; Reisfeld, Ralph A.

    1996-04-01

    Antibody--cytokine fusion proteins combine the unique targeting ability of antibodies with the multifunctional activity of cytokines. Here, we demonstrate the therapeutic efficacy of such constructs for the treatment of hepatic and pulmonary metastases of different melanoma cell lines. Two antibody--interleukin 2 (IL-2) fusion proteins, ch225-IL2 and ch14.18-IL2, constructed by fusion of a synthetic sequence coding for human IL-2 to the carboxyl end of the Cγ 1 gene of the corresponding antibodies, were tested for their therapeutic efficacy against xenografted human melanoma in vivo. Tumorspecific fusion proteins completely inhibited the growth of hepatic and pulmonary metastases in C.B-17 scid/scid mice previously reconstituted with human lymphokine-activated killer cells, whereas treatment with combinations of the corresponding antibodies plus recombinant IL-2 only reduced the tumor load. Even when treatment with fusion proteins was delayed up to 8 days after inoculation of tumor cells, it still resulted in complete eradication of micrometastases that were established at that time point. Selection of tumor cell lines expressing or lacking the targeted antigen of the administered fusion protein proved the specificity of the observed antitumor effect. Biodistribution analysis demonstrated that the tumorspecific fusion protein accumulated not only in subcutaneous tumors but also in lungs and livers affected with micrometastases. Survival times of animals treated with the fusion protein were more than doubled as compared to those treated with the combination of the corresponding antibody plus IL-2. Our data demonstrate that an immunotherapeutic approach using cytokines targeted by antibodies to tumor sites has potent effects against disseminated human melanoma.

  8. Critical epitopes in the nucleocapsid protein of SFTS virus recognized by a panel of SFTS patients derived human monoclonal antibodies.

    Directory of Open Access Journals (Sweden)

    Li Yu

    Full Text Available BACKGROUND: SFTS virus (SFTSV is a newly discovered pathogen to cause severe fever with thrombocytopenia syndrome (SFTS in human. Successful control of SFTSV epidemic requires better understanding of the antigen target in humoral immune responses to the new bunyavirus infection. METHODOLOGY/PRINCIPAL FINDINGS: We have generated a combinatorial Fab antibody phage library from two SFTS patients recovered from SFTSV infection. To date, 94 unique human antibodies have been generated and characterized from over 1200 Fab antibody clones obtained by screening the library with SFTS purified virions. All those monoclonal antibodies (MAbs recognized the nucleocapsid (N protein of SFTSV while none of them were reactive to the viral glycoproteins Gn or Gc. Furthermore, over screening 1000 mouse monoclonal antibody clones derived from SFTSV virions immunization, 462 clones reacted with N protein, while only 16 clones were reactive to glycoprotein. Furthermore, epitope mapping of SFTSV N protein was performed through molecular simulation, site mutation and competitive ELISA, and we found that at least 4 distinct antigenic epitopes within N protein were recognized by those human and mouse MAbs, in particular mutation of Glu10 to Ala10 abolished or significantly reduced the binding activity of nearly most SFTS patients derived MAbs. CONCLUSIONS/SIGNIFICANCE: The large number of human recombinant MAbs derived from SFTS patients recognized the viral N protein indicated the important role of the N protein in humoral responses to SFTSV infection, and the critical epitopes we defined in this study provided molecular basis for detection and diagnosis of SFTSV infection.

  9. Increased antibody responses to human papillomavirus type 16 L1 protein expressed by recombinant vaccinia virus lacking serine protease inhibitor genes.

    Science.gov (United States)

    Zhou, J; Crawford, L; McLean, L; Sun, X Y; Stanley, M; Almond, N; Smith, G L

    1990-09-01

    The L1 gene of human papillomavirus type 16 (HPV-16) driven by the vaccinia virus major late 4b gene promoter has been inserted into three different sites of the vaccinia virus genome. Insertion into the thymidine kinase (TK) gene was achieved by selection of TK- mutants in BUdR on TK- cells. Insertion into two vaccinia virus serine protease inhibitor (serpin) genes was achieved by co-insertion of the Escherichia coli xanthine guanine phosphoribosyltransferase gene linked to the vaccinia virus 7.5K promoter and selection of mycophenolic acid-resistant recombinant viruses. Each recombinant virus expressed a 57K L1 protein at similar levels and with similar kinetics. However, immunization of mice with these recombinant viruses induced different levels of antibody to the L1 protein. Viruses lacking serpin genes B13R and B24R induced significantly higher antibody levels than did viruses lacking the TK gene. The presence of functional B13R and B24R gene products is therefore somehow immunosuppressive at least for antibody responses to the L1 protein of HPV-16.

  10. Measuring protein-protein and protein-nucleic Acid interactions by biolayer interferometry.

    Science.gov (United States)

    Sultana, Azmiri; Lee, Jeffrey E

    2015-01-01

    Biolayer interferometry (BLI) is a simple, optical dip-and-read system useful for measuring interactions between proteins, peptides, nucleic acids, small molecules, and/or lipids in real time. In BLI, a biomolecular bait is immobilized on a matrix at the tip of a fiber-optic sensor. The binding between the immobilized ligand and another molecule in an analyte solution produces a change in optical thickness at the tip and results in a wavelength shift proportional to binding. BLI provides direct binding affinities and rates of association and dissociation. This unit describes an efficient approach using streptavidin-based BLI to analyze DNA-protein and protein-protein interactions. A quantitative set of equilibrium binding affinities (K(d)) and rates of association and dissociation (k(a)/k(d)) can be measured in minutes using nanomole quantities of sample.

  11. Interaction of milk whey protein with common phenolic acids

    Science.gov (United States)

    Zhang, Hao; Yu, Dandan; Sun, Jing; Guo, Huiyuan; Ding, Qingbo; Liu, Ruihai; Ren, Fazheng

    2014-01-01

    Phenolics-rich foods such as fruit juices and coffee are often consumed with milk. In this study, the interactions of α-lactalbumin and β-lactoglobulin with the phenolic acids (chlorogenic acid, caffeic acid, ferulic acid, and coumalic acid) were examined. Fluorescence, CD, and FTIR spectroscopies were used to analyze the binding modes, binding constants, and the effects of complexation on the conformation of whey protein. The results showed that binding constants of each whey protein-phenolic acid interaction ranged from 4 × 105 to 7 × 106 M-n and the number of binding sites n ranged from 1.28 ± 0.13 to 1.54 ± 0.34. Because of these interactions, the conformation of whey protein was altered, with a significant reduction in the amount of α-helix and an increase in the amounts of β-sheet and turn structures.

  12. Solid-phase radioimmunoassay for IgG gliadin antibodies using /sup 125/I-labelled staphylococcal protein A

    Energy Technology Data Exchange (ETDEWEB)

    Troncone, R.; Pignata, C.; Farris, E.; Ciccimarra, F. (Naples Univ. (Italy). II Facolta di Medicina)

    1983-10-14

    A sensitive radioimmunoassay for IgG gliadin antibodies is described. Serum specimens were added to wells of plastic microtitre plates coated with gliadin. After removal of the unbound material, gliadin antibodies were detected by adding /sup 125/I-labelled staphylococcal protein A (/sup 125/I-SpA). Serum specimens from coeliac patients on a normal diet or on a gluten-free diet were tested, as well as sera from an age-matched control group. Measurements to obtain precise quantitative values were made with gliadin antibody-rich serum as reference standard. High titres of gliadin antibodies were found in 18 out of 19 coeliac patients on a normal diet (95%); in patients on a strict gluten-free diet serum values did not exceed 2 S.D. of the control mean. Due to the high sensitivity of the method a low but detectable amount of gliadin antibody was present in the sera of all controls.

  13. Antibody Response is More Likely to Pneumococcal Proteins Than to Polysaccharide After HIV-associated Invasive Pneumococcal Disease

    DEFF Research Database (Denmark)

    Kantsø, Bjørn; Green, Nicola; Goldblatt, David;

    2015-01-01

    BACKGROUND: Human immunodeficiency virus (HIV)-infected individuals are at increased risk of invasive pneumococcal disease (IPD). In order to assess the immunogenicity of pneumococcal proteins and polysaccharide, we investigated protein and serotype-specific antibody responses after HIV......-associated IPD. METHODS: Specific antipneumococcal immunoglobulin G to 27 pneumococcal protein antigens and 30 serotype polysaccharides was measured in plasma before and after IPD in HIV-infected individuals and compared to HIV-infected individuals without IPD. RESULTS: Over time, 81% of IPD cases responded...... to at least 1 protein compared to 51% of non-IPD controls. HIV IPD cases responded to more proteins than non-IPD controls (8.6 ± 8.4 vs 4.2 ± 7.6 proteins; P = .01), and had a significantly higher probability of yielding an antibody response to the proteins PiaA, PsaA, and PcpA. Twenty-two percent of HIV...

  14. Informational Way to Protein Alphabet: Entropic Classification of Amino Acids

    CERN Document Server

    Gorban, A N; Popova, T

    2007-01-01

    What are proteins made from, as the working parts of the living cells protein machines? To answer this question, we need a technology to disassemble proteins onto elementary func-tional details and to prepare lumped description of such details. This lumped description might have a multiple material realization (in amino acids). Our hypothesis is that informational approach to this problem is possible. We propose a way of hierarchical classification that makes the primary structure of protein maximally non-random. The first steps of the suggested research program are realized: the method and the analysis of optimal informational protein binary alphabet. The general method is used to answer several specific questions, for example: (i) Is there a syntactic difference between Globular and Membrane proteins? (ii) Are proteins random sequences of amino acids (a long discussion)? For these questions, the answers are as follows: (i) There exists significant syntactic difference between Globular and Membrane proteins,...

  15. INHIBITION OF IN VITRO FERTILIZATION IN THE HAMSTER BY ANTIBODIES RAISED AGAINST THE RAT SPERM PROTEIN SP22

    Science.gov (United States)

    INHIBITION OF IN VITRO FERTILIZATION IN THE HAMSTER BY ANTIBODIES RAISED AGAINST THE RAT SPERM PROTEIN SP22. SC Jeffay*, SD Perreault, KL Bobseine*, JE Welch*, GR Klinefelter, US EPA, Research Triangle Park, NC. SP22, a rat sperm membrane protein that is highly-correlated w...

  16. Separation of monoclonal antibody charge state variants by open tubular capillary electrochromatography with immobilised protein as stationary phase.

    Science.gov (United States)

    Zhang, Yamin; Wang, Wentao; Xiao, Xue; Jia, Li

    2016-09-30

    Monoclonal antibodies (mAbs) are highly heterogeneous and complex glycoproteins requiring powerful analytical tools for characterization and quality control. In this work, we utilize adsorbed bovine serum albumin (BSA) as a stationary phase in open tubular (OT) capillary electrochromatography for separation of charge state variants of mAbs. Poly(diallydimethylammonium chloride) (PDDA) was used to assist fabrication of BSA coated OT column by electrostatic self-assembly. Scanning electron microscopy and electroosmotic flow measurement were carried out to characterize the as-prepared BSA coated PDDA OT columns. The electrochromatographic performance of the OT columns was evaluated by separation of basic proteins and different charge state variants of mAbs. The effects of background solution pH and concentration on separation were investigated. A rapid separation of charge state variants of mAbs was successfully achieved in the BSA coated PDDA OT column. Separation of seven variants of the mAb cetuximab was achieved using the prepared column. Two basic variants and one acidic variant of rituximab, and two basic variants and four acidic variants of trastuximab were successfully distinguished from the main forms. In addition, the columns demonstrated good repeatability and stability with the run-to-run, day-to-day and batch-to-batch relative standard deviations of migration times less than 3.7%.

  17. Standardization of natural mycolic acid antigen composition and production for use in biomarker antibody detection to diagnose active tuberculosis.

    Science.gov (United States)

    Ndlandla, F L; Ejoh, V; Stoltz, A C; Naicker, B; Cromarty, A D; van Wyngaardt, S; Khati, M; Rotherham, L S; Lemmer, Y; Niebuhr, J; Baumeister, C R; Al Dulayymi, J R; Swai, H; Baird, M S; Verschoor, J A

    2016-08-01

    Mycobacterium tuberculosis, the causative agent of tuberculosis, is characterized by the abundance of species specific, antigenic cell wall lipids called mycolic acids. These wax-like molecules all share an identical, amphiphilic mycolic motif, but have different functional groups in a long hydrophobic hydrocarbon mero-chain that divide them into three main classes: alpha-, keto- and methoxy-mycolic acids. Whereas alpha-mycolic acids constitutively maintain an abundance of around 50%, the ratio of methoxy- to keto-mycolic acid types may vary depending on, among other things, the growth stage of M. tuberculosis. In human patients, antibodies to mycolic acids have shown potential as diagnostic serum biomarkers for active TB. Variations in mycolic acid composition affect the antigenic properties and can potentially compromise the precision of detection of anti-mycolic acids antibodies in patient sera to natural mixtures. We demonstrate this here with combinations of synthetic mycolic acid antigens, tested against TB patient and control sera. Combinations of methoxy- and α-mycolic acids are more antigenic than combinations of keto- and α-mycolic acids, showing the former to give a more sensitive test for TB biomarker antibodies. Natural mixtures of mycolic acids isolated from mature cultures of M. tuberculosis H37Rv give the same sensitivity as that with synthetic methoxy- and α-mycolic acids in combination, in a surface plasmon resonance inhibition biosensor test. To ensure that the antigenic activity of isolates of natural mycolic acids is reproducible, we cultured M. tuberculosis H37Rv on Middlebrook 7H10 solid agar plates to stationary growth phase in a standardized, optimal way. The proportions of mycolic acid classes in various batches of the isolates prepared from these cultures were compared to a commercially available natural mycolic acid isolate. LC-MS/MS and NMR data for quantitation of mycolic acids class compositions show that the variation in batches

  18. Use of non-structural proteins to FMDV to assess antibodies in vaccinated and infected cattle in Peru

    International Nuclear Information System (INIS)

    The identification of animals that have been infected with FMDV is very important for the control measures of the disease, because the animals frequently become carriers and can be the cause of new outbreaks. In countries were vaccination is applied it is recognised that there is the necessity to use tests that can differentiate the antibodies resulted from the vaccine and the antibodies from infection. In recent years tests have been developed that identify antibodies against virus-specific proteins present only in infected animals, being the non-structural protein 2C and non-structural 3ABC polyprotein the most studied. The work made under the CRP can be divided into three phases. (1) Examination of a set of tests provided up to 2002; (2) Examination of tests provided from 2002 to present and; (3) Studies on post vaccinated animal to examine whether antibodies to NSP are produced. (author)

  19. Monoclonal antibodies against DNA-binding tips of DNABII proteins disrupt biofilms in vitro and induce bacterial clearance in vivo

    Directory of Open Access Journals (Sweden)

    Laura A. Novotny

    2016-08-01

    Full Text Available The vast majority of chronic and recurrent bacterial diseases are attributed to the presence of a recalcitrant biofilm that contributes significantly to pathogenesis. As such, these diseases will require an innovative therapeutic approach. We targeted DNABII proteins, an integral component of extracellular DNA (eDNA which is universally found as part of the pathogenic biofilm matrix to develop a biofilm disrupting therapeutic. We show that a cocktail of monoclonal antibodies directed against specific epitopes of a DNABII protein is highly effective to disrupt diverse biofilms in vitro as well as resolve experimental infection in vivo, in both a chinchilla and murine model. Combining this monoclonal antibody cocktail with a traditional antibiotic to kill bacteria newly released from the biofilm due to the action of the antibody cocktail was highly effective. Our results strongly support these monoclonal antibodies as attractive candidates for lead optimization as a therapeutic for resolution of bacterial biofilm diseases.

  20. GAMBARAN PERKEMBANGAN ANTIBODI TERHADAP KOMPONEN PROTEIN CACING MIKROFILARIA MALAYI DARI TRANSMIGRAN DI SULAWESI TENGGARA

    Directory of Open Access Journals (Sweden)

    Basundari Sri Utami

    2012-09-01

    Full Text Available The immune response to microfilarial antigen in malayan filariasis was found more prominent in ami-crofilaremic individuals than in the micro filaremics. It has been shown that in amicrofilaremic individuals antibody plays a role in reducing micro filaremiae. The targets antigens of antibody (IgG were shown to be protein components of microfilariae with molecular weight of 75, 70 and 25 Kd. This prospective study was aimed at detecting IgG against microfilariae in transmigrats, who had settled into an filarial endemic area. Sera of 10 individuals at 8, 13, 26, 39 and 52 moths after settling, were examined by ELISA and Wes­tern Blott against microfilaria of B. malayi. Four out of 10 transmigrants showed IgG that recognized the protein components of 77, 70 and 31 Kd and were shown at 39, 52 and 8 months after settling respectively, The IgG against components of 77 and 70 Kd were revealed later than the one against 31 Kd.

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

    Directory of Open Access Journals (Sweden)

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

    2016-06-01

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

  2. Patterning of Functional Antibodies and Other Proteins by Photolithography of Silane Monolayers

    Science.gov (United States)

    Mooney, J. F.; Hunt, A. J.; McIntosh, J. R.; Liberko, C. A.; Walba, D. M.; Rogers, C. T.

    1996-10-01

    We have demonstrated the assembly of two-dimensional patterns of functional antibodies on a surface. In particular, we have selectively adsorbed micrometer-scale regions of biotinylated immunoglobulin that exhibit specific antigen binding after adsorption. The advantage of this technique is its potential adaptability to adsorbing arbitrary proteins in tightly packed monolayers while retaining functionality. The procedure begins with the formation of a self-assembled monolayer of n-octadecyltrimethoxysilane (OTMS) on a silicon dioxide surface. This monolayer can then be selectively removed by UV photolithography. Under appropriate solution conditions, the OTMS regions will adsorb a monolayer of bovine serum albumin (BSA), while the silicon dioxide regions where the OTMS has been removed by UV light will adsorb less than 2% of a monolayer, thus creating high contrast patterned adsorption of BSA. The attachment of the molecule biotin to the BSA allows the pattern to be replicated in a layer of streptavidin, which bonds to the biotinylated BSA and in turn will bond an additional layer of an arbitrary biotinylated protein. In our test case, functionality of the biotinylated goat antibodies raised against mouse immunoglobulin was demonstrated by the specific binding of fluorescently labeled mouse IgG.

  3. Modifications of proteins by polyunsaturated fatty acid peroxidation products

    DEFF Research Database (Denmark)

    Refsgaard, Hanne; Tsai, Lin; Stadtman, Earl

    2000-01-01

    The ability of unsaturated fatty acid methyl esters to modify amino acid residues in bovine serum albumin (BSA), glutamine synthetase, and insulin in the presence of a metal-catalyzed oxidation system [ascorbate/Fe(lll)/O-2] depends on the degree of unsaturation of the fatty acid. The fatty acid...... of BSA were significantly lower than that observed in the absence of BSA. Direct treatment of proteins with various lipid hydroperoxides led to a slight increase in the formation of protein carbonyl derivatives, whereas treatment with the hydroperoxides together with Fe(ll) led to a substantial increase...

  4. Interaction of allergy history and antibodies to specific varicella-zoster virus proteins on glioma risk.

    Science.gov (United States)

    Lee, Seung-Tae; Bracci, Paige; Zhou, Mi; Rice, Terri; Wiencke, John; Wrensch, Margaret; Wiemels, Joseph

    2014-05-01

    Glioma is the most common cancer of the central nervous system but with few confirmed risk factors. It has been inversely associated with chicken pox, shingles and seroreactivity to varicella virus (VZV), as well as to allergies and allergy-associated IgE. The role of antibody reactivity against individual VZV antigens has not been assessed. Ten VZV-related proteins, selected for high immunogenicity or known function, were synthesized and used as targets for antibody measurements in the sera of 143 glioma cases and 131 healthy controls selected from the San Francisco Bay Area Adult Glioma Study. Glioma cases exhibited significantly reduced seroreactivity compared to controls for six antigens, including proteins IE63 [odds ratio (OR) = 0.26, 95% confidence interval (CI): 0.12-0.58, comparing lowest quartile to highest) and the VZV-unique protein ORF2p (OR = 0.44, 95% CI: 0.21-0.96, lowest quartile to highest). When stratifying the study population into those with low and high self-reported allergy history, VZV protein seroreactivity was only associated inversely with glioma among individuals self-reporting more than two allergies. The data provide insight into both allergy and VZV effects on glioma: strong anti-VZV reactions in highly allergic individuals are associated with reduced occurrence of glioma. This result suggests a role for specificity in the anti-VZV immunity in brain tumor suppression for both individual VZV antigens and in the fine-tuning of the immune response by allergy. Anti-VZV reactions may also be a biomarker of effective CNS immunosurveillance owing to the tropism of the virus. PMID:24127236

  5. Direct, Specific and Rapid Detection of Staphylococcal Proteins and Exotoxins Using a Multiplex Antibody Microarray.

    Directory of Open Access Journals (Sweden)

    Bettina Stieber

    Full Text Available S. aureus is a pathogen in humans and animals that harbors a wide variety of virulence factors and resistance genes. This bacterium can cause a wide range of mild to life-threatening diseases. In the latter case, fast diagnostic procedures are important. In routine diagnostic laboratories, several genotypic and phenotypic methods are available to identify S. aureus strains and determine their resistances. However, there is a demand for multiplex routine diagnostic tests to directly detect staphylococcal toxins and proteins.In this study, an antibody microarray based assay was established and validated for the rapid detection of staphylococcal markers and exotoxins. The following targets were included: staphylococcal protein A, penicillin binding protein 2a, alpha- and beta-hemolysins, Panton Valentine leukocidin, toxic shock syndrome toxin, enterotoxins A and B as well as staphylokinase. All were detected simultaneously within a single experiment, starting from a clonal culture on standard media. The detection of bound proteins was performed using a new fluorescence reading device for microarrays.110 reference strains and clinical isolates were analyzed using this assay, with a DNA microarray for genotypic characterization performed in parallel. The results showed a general high concordance of genotypic and phenotypic data. However, genotypic analysis found the hla gene present in all S. aureus isolates but its expression under given conditions depended on the clonal complex affiliation of the actual isolate.The multiplex antibody assay described herein allowed a rapid and reliable detection of clinically relevant staphylococcal toxins as well as resistance- and species-specific markers.

  6. Antibodies to Chlamydia trachomatis heat shock proteins in women with tubal factor infertility are associated with prior infection by C. trachomatis but not by C. pneumoniae

    DEFF Research Database (Denmark)

    Persson, K; Osser, S; Birkelund, Svend;

    1999-01-01

    The antibody response to heat shock proteins 60 and 10 were studied in 163 patients with tubal factor infertility and in 163 age-matched pregnant women. The associations of these antibodies with specific antibodies to Chlamydia trachomatis and to Chlamydia pneumoniae as well as with antibodies to...... shock proteins and to C. trachomatis but no independent influence of antibodies to C. pneumoniae. No interaction between C. trachomatis and C. pneumoniae suggesting a synergistic effect was found although the heat shock proteins from these two organisms are immunologically similar. Antibodies to the...... the common chlamydial lipopolysaccharide antigen were studied. Patients with tubal factor infertility had significantly higher frequencies and titres of all antibodies except to C. pneumoniae. In a logistic regression model an association was found between the prevalence of antibodies to the heat...

  7. Dengue serotype cross-reactive, anti-E protein antibodies confound specific immune memory for one year after infection

    Directory of Open Access Journals (Sweden)

    Ying Xiu eToh

    2014-08-01

    Full Text Available Dengue virus has four serotypes and is endemic globally in tropical countries. Neither a specific treatment nor an approved vaccine is available, and correlates of protection are not established. The standard neutralization assay cannot differentiate between serotype-specific and serotype cross-reactive antibodies in patients early after infection, leading to an overestimation of the long-term serotype-specific protection of an antibody response. It is known that the cross-reactive response in patients is temporary but few studies have assessed kinetics and potential changes in serum antibody specificity over time. To better define the specificity of polyclonal antibodies during disease and after recovery, longitudinal samples from patients with primary or secondary DENV-2 infection were collected over a period of one year. We found that serotype cross-reactive antibodies peaked three weeks after infection and subsided within one year. Since secondary patients rapidly produced antibodies specific for the virus envelope (E protein, an E-specific ELISA was superior compared to a virus particle-specific ELISA to identify patients with secondary infections. Dengue infection triggered a massive activation and mobilization of both naïve and memory B cells possibly from lymphoid organs into the blood, providing an explanation for the surge of circulating plasmablasts and the increase in cross-reactive E protein-specific antibodies.

  8. An alternative easy method for antibody purification and analysis of protein-protein interaction using GST fusion proteins immobilized onto glutathione-agarose.

    Science.gov (United States)

    Zalazar, L; Alonso, C A I; De Castro, R E; Cesari, A

    2014-01-01

    Immobilization of small proteins designed to perform protein-protein assays can be a difficult task. Often, the modification of reactive residues necessary for the interaction between the immobilized protein and the matrix compromises the interaction between the protein and its target. In these cases, glutathione-S-transferase (GST) is a valuable tag providing a long arm that makes the bait protein accessible to the mobile flow phase of the chromatography. In the present report, we used a GST fusion version of the 8-kDa protein serine protease inhibitor Kazal-type 3 (SPINK3) as the bait to purify anti-SPINK3 antibodies from a rabbit crude serum. The protocol for immobilization of GST-SPINK3 to glutathione-agarose beads was modified from previously reported protocols by using an alternative bifunctional cross-linker (dithiobis(succinimidyl propionate)) in a very simple procedure and by using simple buffers under physiological conditions. We concluded that the immobilized protein remained bound to the column after elution with low pH, allowing the reuse of the column for alternative uses, such as screening for other protein-protein interactions using SPINK3 as the bait.

  9. Increased titers of neutralizing antibodies after immunization with both envelope proteins of the porcine endogenous retroviruses (PERVs

    Directory of Open Access Journals (Sweden)

    Denner Joachim

    2012-11-01

    Full Text Available Abstract Despite enormous difficulties to induce antibodies neutralizing HIV-1, especially broadly neutralizing antibodies directed against the conserved membrane proximal external region (MPER of the transmembrane envelope protein, such antibodies can be easily induced in the case of gammaretroviruses, among them the porcine endogenous retroviruses (PERVs. In addition to neutralizing antibodies directed against the transmembrane envelope protein p15E, neutralizing antibodies were also induced by immunization with the surface envelope protein gp70. PERVs represent a special risk for xenotransplantation using pig tissues or organs since they are integrated in the genome of all pigs and infect human cells and a vaccine may protect from transmission to the recipient. To investigate the effect of simultaneous immunization with both proteins in detail, a study was performed in hamsters. Gp70 and p15E of PERV were produced in E. coli, purified and used for immunization. All animals developed binding antibodies against the antigens used for immunization. Sera from animals immunized with p15E recognized epitopes in the MPER and the fusion peptide proximal region (FPPR of p15E. One MPER epitope showed a sequence homology to an epitope in the MPER of gp41 of HIV-1 recognized by broadly neutralizing antibodies found in HIV infected individuals. Neutralizing antibodies were detected in all sera. Most importantly, sera from animals immunized with gp70 had a higher neutralizing activity when compared with the sera from animals immunized with p15E and sera from animals immunized with gp70 together with p15E had a higher neutralizing activity compared with sera from animals immunized with each antigen alone. These immunization studies are important for the development of vaccines against other retroviruses including the human immunodeficiency virus HIV-1.

  10. Development and application of an antibody-based protein microarray to assess physiological stress in grizzly bears (Ursus arctos).

    Science.gov (United States)

    Carlson, Ruth I; Cattet, Marc R L; Sarauer, Bryan L; Nielsen, Scott E; Boulanger, John; Stenhouse, Gordon B; Janz, David M

    2016-01-01

    A novel antibody-based protein microarray was developed that simultaneously determines expression of 31 stress-associated proteins in skin samples collected from free-ranging grizzly bears (Ursus arctos) in Alberta, Canada. The microarray determines proteins belonging to four broad functional categories associated with stress physiology: hypothalamic-pituitary-adrenal axis proteins, apoptosis/cell cycle proteins, cellular stress/proteotoxicity proteins and oxidative stress/inflammation proteins. Small skin samples (50-100 mg) were collected from captured bears using biopsy punches. Proteins were isolated and labelled with fluorescent dyes, with labelled protein homogenates loaded onto microarrays to hybridize with antibodies. Relative protein expression was determined by comparison with a pooled standard skin sample. The assay was sensitive, requiring 80 µg of protein per sample to be run in triplicate on the microarray. Intra-array and inter-array coefficients of variation for individual proteins were generally bears. This suggests that remotely delivered biopsy darts could be used in future sampling. Using generalized linear mixed models, certain proteins within each functional category demonstrated altered expression with respect to differences in year, season, geographical sampling location within Alberta and bear biological parameters, suggesting that these general variables may influence expression of specific proteins in the microarray. Our goal is to apply the protein microarray as a conservation physiology tool that can detect, evaluate and monitor physiological stress in grizzly bears and other species at risk over time in response to environmental change.

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

    Directory of Open Access Journals (Sweden)

    Roopali eRajput

    2015-09-01

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

  12. FLU, an amino acid substitution model for influenza proteins

    OpenAIRE

    Gascuel Olivier; Le Quang; Dang Cuong; Le Vinh

    2010-01-01

    Abstract Background The amino acid substitution model is the core component of many protein analysis systems such as sequence similarity search, sequence alignment, and phylogenetic inference. Although several general amino acid substitution models have been estimated from large and diverse protein databases, they remain inappropriate for analyzing specific species, e.g., viruses. Emerging epidemics of influenza viruses raise the need for comprehensive studies of these dangerous viruses. We p...

  13. Phthalic Acid Chemical Probes Synthesized for Protein-Protein Interaction Analysis

    Directory of Open Access Journals (Sweden)

    Chin-Jen Wu

    2013-06-01

    Full Text Available Plasticizers are additives that are used to increase the flexibility of plastic during manufacturing. However, in injection molding processes, plasticizers cannot be generated with monomers because they can peel off from the plastics into the surrounding environment, water, or food, or become attached to skin. Among the various plasticizers that are used, 1,2-benzenedicarboxylic acid (phthalic acid is a typical precursor to generate phthalates. In addition, phthalic acid is a metabolite of diethylhexyl phthalate (DEHP. According to Gene_Ontology gene/protein database, phthalates can cause genital diseases, cardiotoxicity, hepatotoxicity, nephrotoxicity, etc. In this study, a silanized linker (3-aminopropyl triethoxyslane, APTES was deposited on silicon dioxides (SiO2 particles and phthalate chemical probes were manufactured from phthalic acid and APTES–SiO2. These probes could be used for detecting proteins that targeted phthalic acid and for protein-protein interactions. The phthalic acid chemical probes we produced were incubated with epithelioid cell lysates of normal rat kidney (NRK-52E cells to detect the interactions between phthalic acid and NRK-52E extracted proteins. These chemical probes interacted with a number of chaperones such as protein disulfide-isomerase A6, heat shock proteins, and Serpin H1. Ingenuity Pathways Analysis (IPA software showed that these chemical probes were a practical technique for protein-protein interaction analysis.

  14. Production and Characterization of Monoclonal Antibodies against Human Nuclear Protein FAM76B.

    Directory of Open Access Journals (Sweden)

    Xiaojing Zheng

    Full Text Available Human FAM76B (hFAM76B is a 39 kDa protein that contains homopolymeric histidine tracts, a targeting signal for nuclear speckles. FAM76B is highly conserved among different species, suggesting that it may play an important physiological role in normal cellular functions. However, a lack of appropriate tools has hampered study of this potentially important protein. To facilitate research into the biological function(s of FAM76B, murine monoclonal antibodies (MAbs against hFAM76B were generated by using purified, prokaryotically expressed hFAM76B protein. Six strains of MAbs specific for hFAM76B were obtained and characterized. The specificity of MAbs was validated by using FAM76B-/- HEK 293 cell line. Double immunofluorescence followed by laser confocal microscopy confirmed the nuclear speckle localization of hFAM76B, and the specific domains recognized by different MAbs were further elucidated by Western blot. Due to the high conservation of protein sequences between mouse and human FAM76B, MAbs against hFAM76B were shown to react with mouse FAM76B (mFAM76B specifically. Lastly, FAM76B was found to be expressed in the normal tissues of most human organs, though to different extents. The MAbs produced in this study should provide a useful tool for investigating the biological function(s of FAM76B.

  15. Plasma antibodies to heat shock protein 60 and heat shock protein 70 are associated with increased risk of electrocardiograph abnormalities in automobile workers exposed to noise

    OpenAIRE

    Yuan, Jing; Yang, Miao; Yao, Huiling; Zheng, Jianru; Yang, Qiaoling; Chen, Sheng; Wei, Qingyi; Tanguay, Robert M.; Wu, Tangchun

    2005-01-01

    In the living and working environment, stressful factors, such as noise, can cause health problems including cardiovascular diseases and noise-induced hearing loss. Some heat shock proteins (Hsps) play an important role in protecting cardiac cells against ischemic injury, and antibodies against these Hsps are associated with the development and prognosis of atherogenesis, coronary heart disease, and hypertension. Whether the presence of such antibodies is associated with abnormal electrocardi...

  16. Fatty acid transfer between multilamellar liposomes and fatty acid-binding proteins.

    Science.gov (United States)

    Brecher, P; Saouaf, R; Sugarman, J M; Eisenberg, D; LaRosa, K

    1984-11-10

    A simple experimental system was developed for studying the movement of long-chain fatty acids between multilamellar liposomes and soluble proteins capable of binding fatty acids. Oleic acid was incorporated into multilamellar liposomes containing cholesterol and egg yolk lecithin and incubated with albumin or hepatic fatty acid-binding protein. It was found that the fatty acid transferred from the liposomes to either protein rapidly and selectively under conditions where phospholipid and cholesterol transfer did not occur. More than 50% of the fatty acid contained within liposomes could become protein bound, suggesting that the fatty acid moved readily between and across phospholipid bilayers. Transfer was reduced at low pH, and this reduction appeared to result from decreased dissociation of the protonated fatty acid from the bilayer. Liposomes made with dimyristoyl or dipalmitoyl lecithin and containing 1 mol per cent palmitic acid were used to show the effect of temperature on fatty acid transfer. Transfer to either protein did not occur at temperatures where the liposomes were in a gel state but occurred rapidly at temperatures at or above the transition temperatures of the phospholipid used. PMID:6490659

  17. IGF2BP2 alternative variants associated with glutamic acid decarboxylase antibodies negative diabetes in Malaysian subjects.

    Directory of Open Access Journals (Sweden)

    Sameer D Salem

    Full Text Available BACKGROUND: The association of Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2 common variants (rs4402960 and rs1470579 with type 2 diabetes (T2D has been performed in different populations. The aim of this study was to evaluate the association of alternative variants of IGF2BP2; rs6777038, rs16860234 and rs7651090 with glutamic acid decarboxylase antibodies (GADA negative diabetes in Malaysian Subjects. METHODS/PRINCIPAL FINDINGS: IGF2BP2; rs6777038, rs16860234 and rs7651090 single nucleotide polymorphisms (SNPs were genotyped in 1107 GADA negative diabetic patients and 620 control subjects of Asian from Malaysia. The additive genetic model adjusted for age, race, gender and BMI showed that alternative variants; rs6777038, rs16860234 and rs7651090 of IGF2BP2 associated with GADA negative diabetes (OR = 1.21; 1.36; 1.35, P = 0.03; 0.0004; 0.0002, respectively. In addition, the CCG haplotype and diplotype CCG-TCG increased the risk of diabetes (OR = 1.51, P = 0.01; OR = 2.36, P = 0.009, respectively. CONCLUSIONS/SIGNIFICANCE: IGF2BP2 alternative variants were associated with GADA negative diabetes. The IGF2BP2 haplotypes and diplotypes increased the risk of diabetes in Malaysian subject.

  18. Myelin protein zero and its antibody in serum as biomarkers of n-hexane-induced peripheral neuropathy and neurotoxicity effects

    Institute of Scientific and Technical Information of China (English)

    Jia Xiaowei; Liu Qingjun; Zhang Yanshu; Dai Yufei; Duan Huawei; Bin Ping; Niu Yong

    2014-01-01

    Background Chronic exposure to n-hexane can lead to peripheral neuropathy that no effective treatment regimen could be applied presently.This study investigated whether myelin protein zero (P0) protein and its antibody could be used to distinguish n-hexane intoxication and protect workers from peripheral neuropathy.Methods We compared P0 protein and its antibody among three levels of n-hexane-exposed groups,which included 18 patients with n-hexane-induced peripheral neuropathy as case group,120 n-hexane-exposed workers as n-hexaneexposed control group,and 147 non-hexane-exposed participants used as control group.ELISA method was applied to detect P0 protein and its antibody.Results P0 protein in serum was significantly higher in the case group and n-hexane-exposed control group in comparison with the control group (P<0.01).Compared with the n-hexane-exposed control group,the case group also had significant increase of P0 protein (P<0.01).After 6 months therapy,P0 protein was observed to decrease significantly in the case group (P<0.01).The P0 antibody in serum was significantly higher in the n-hexane-exposed control group than in the control group (P<0.01),but not significantly different between cases and controls.Conclusions P0 antibodies in serum may be a short-term effect biomarker for n-hexane exposure.P0 protein in serum may be an early effective biomarker for peripheral nerve neuropathy and its biological limit value needs investigation in the future study.

  19. Polyclonal antibody preparation and expression in liver tissues of transactivated protein 5 of hepatitis C virus nonstructural 5A

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Objective To prepare polyclonal antibody of transactivated protein 5 of hepatitis C virus nonstructural 5A (NA5ATP5) and to explore its expression in the liver tissues. Methods In Escherichia coli BL21,the prokaryotic expression vector pET32a(+)-NS5ATP5 was induced by isopropyl-β-D-thiogalactoside (IPTG),and it was analyzed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. And the purified protein was used to immunize the rabbit to prepare polyclonal antibody,wi...

  20. Buffer Interference with Protein Dynamics: A Case Study on Human Liver Fatty Acid Binding Protein

    OpenAIRE

    Long, Dong; Yang, Daiwen

    2009-01-01

    Selection of suitable buffer types is often a crucial step for generating appropriate protein samples for NMR and x-ray crystallographic studies. Although the possible interaction between MES buffer (2-(N-morpholino)ethanesulfonic acid) and proteins has been discussed previously, the interaction is usually thought to have no significant effects on the structures of proteins. In this study, we demonstrate the direct, albeit weak, interaction between MES and human liver fatty acid binding prote...

  1. Manipulating Fatty Acid Biosynthesis in Microalgae for Biofuel through Protein-Protein Interactions

    OpenAIRE

    Jillian L Blatti; Joris Beld; Behnke, Craig A; Michael Mendez; Mayfield, Stephen P; Burkart, Michael D.

    2012-01-01

    Microalgae are a promising feedstock for renewable fuels, and algal metabolic engineering can lead to crop improvement, thus accelerating the development of commercially viable biodiesel production from algae biomass. We demonstrate that protein-protein interactions between the fatty acid acyl carrier protein (ACP) and thioesterase (TE) govern fatty acid hydrolysis within the algal chloroplast. Using green microalga Chlamydomonas reinhardtii (Cr) as a model, a structural simulation of docking...

  2. A case of anti-nuclear matrix protein 2 antibody positive myopathy associated with lung cancer.

    Science.gov (United States)

    Ohta, Shin; Unoda, Ki-Ichi; Nakajima, Hideto; Ikeda, Soichiro; Hamaguchi, Yasuhito; Kimura, Fumiharu

    2016-08-31

    Myositis-specific autoantibodies (MSAs) are associated with myositis. Anti-nuclear matrix protein 2 (NXP-2) antibody was recently identified as a major MSA and was observed mostly in juvenile dermatomyositis. We report the case of a 44-year-old man who presented with myopathy with anti-NXP-2 antibody and large cell carcinoma of the lung. He was hospitalized because of myalgia and edema of limbs. Neurological examination revealed mild proximal-dominant weakness in all four extremities, and laboratory studies showed elevated creatine kinase level (6,432 IU/l). Needle electromyography showed myogenic patterns. MRI of the lower limbs demonstrated inflammatory lesions in the thighs. Biopsied specimen from the left quadriceps femoris muscle showed mild mononuclear inflammatory infiltrate surrounding muscle fibres but no fiber necrosis. He was diagnosed with myopathy based on neurological examinations and clinical symptoms. His chest X-ray and CT showed tumor shadow on the right upper lung field, but CT didn't indicate the findings of interstitial lung disease. This was surgically removed, and a histological diagnosis of non-small cell lung cancer was suspected. He was also treated with definitive chemoradiotherapy before and after operation. His symptoms of myopathy promptly remitted with the preoperative chemotherapy. His serum analysis was positive for the anti-NXP-2. Further investigation and experience of MSAs are necessary to evaluate the therapeutic strategy against cancer-associated myopathy/myositis. PMID:27477574

  3. Host cell protein impurities in chromatographic polishing steps for monoclonal antibody purification.

    Science.gov (United States)

    Levy, Nicholas E; Valente, Kristin N; Lee, Kelvin H; Lenhoff, Abraham M

    2016-06-01

    Downstream purification of monoclonal antibodies (mAbs) is normally performed using a platform process that is empirically tuned to optimize impurity removal for each new product. A more fundamental understanding of impurities and the product itself would provide insights into the rational design of efficient downstream processes. This work examines the chromatographic properties of Chinese hamster ovary host cell protein (HCP) impurities in non-affinity chromatographic resins commonly used in polishing steps for monoclonal antibody purification: ion-exchange, hydrophobic interaction, and multimodal. Using proteomic analysis, the specific HCP impurities that elute close to mAb products are identified for these resins at typical downstream processing conditions. Additionally, the interactions of HCP impurities with mAb products are profiled to determine the total extent of product association and the specific HCP species that form associative complexes under conditions encountered in polishing columns. Product association and co-elution were both identified as viable mechanisms of HCP retention for the non-affinity resins tested here. A relatively large sub-population of HCP impurities was found to co-elute or associate with mAbs in each polishing column, but only a small population of HCPs-including lipoprotein lipase, chrondroitin sulfate proteoglycan 4, nidogen-1, and SPARC-were identified as difficult to remove across an entire downstream mAb process. Biotechnol. Bioeng. 2016;113: 1260-1272. © 2015 Wiley Periodicals, Inc. PMID:26550778

  4. Detection of Antibodies to Brucella Cytoplasmic Proteins in the Cerebrospinal Fluid of Patients with Neurobrucellosis

    Science.gov (United States)

    Baldi, Pablo C.; Araj, George F.; Racaro, Graciela C.; Wallach, Jorge C.; Fossati, Carlos A.

    1999-01-01

    The diagnosis of human neurobrucellosis usually relies on the detection of antibodies to Brucella lipopolysaccharide (LPS) in cerebrospinal fluid (CSF) by agglutination tests or enzyme-linked immunosorbent assay (ELISA). Here we describe the detection of immunoglobulin G (IgG) to cytoplasmic proteins (CP) of Brucella spp. by ELISA and Western blotting in seven CSF samples from five patients with neurobrucellosis. While IgG to CP (titers of 200 to 12,800) and IgG to LPS (800 to 6,400) were found in the CSF of these patients, these antibodies were not detected in CSF samples from two patients who had systemic brucellosis without neurological involvement. The latter, however, had serum IgG and IgM to both LPS and CP. No reactivity to these antigens was found in CSF samples from 14 and 20 patients suffering from nonbrucellar meningitis and noninfectious diseases, respectively. These findings suggest that, in addition to its usefulness in the serological diagnosis of human systemic brucellosis, the ELISA with CP antigen can be used for the specific diagnosis of human neurobrucellosis. PMID:10473531

  5. Three different conformational states of pregnancy zone protein identified by monoclonal antibodies.

    Science.gov (United States)

    Carlsson-Bosted, L; Moestrup, S K; Gliemann, J; Sottrup-Jensen, L; Stigbrand, T

    1988-05-15

    Human pregnancy zone protein (PZP), related to human alpha 2-macroglobulin, forms dimeric/tetrameric (360/720 kDa) species. PZP binds proteinases which cause the cleavage of internal thiol esters in the molecule. Both the binding of proteinases, i.e. chymotrypsin, (CT) to PZP, forming PZP.CT complexes, or reaction with methylamine (MA) forming PZP.MA complexes, cause transition to a new similar conformational state. Reactivity of selected monoclonal antibodies against PZP towards the three PZP derivatives demonstrated differences in the reactivity pattern. PZP and PZP.MA share one determinant, which is missing on the PZP.CT complex. PZP after transition to PZP.CT, but not to PZP.MA, presents a neodeterminant detected by one of six monoclonal antibodies. The findings demonstrate that at least three different conformational states exist for PZP and its derivatives. Access to discriminating immunochemical tools makes possible an evaluation of the relative abundance of the different complexes in vivo.

  6. A covalent and cleavable antibody-DNA conjugation strategy for sensitive protein detection via immuno-PCR

    Science.gov (United States)

    van Buggenum, Jessie A. G. L.; Gerlach, Jan P.; Eising, Selma; Schoonen, Lise; van Eijl, Roderick A. P. M.; Tanis, Sabine E. J.; Hogeweg, Mark; Hubner, Nina C.; van Hest, Jan C.; Bonger, Kimberly M.; Mulder, Klaas W.

    2016-01-01

    Immuno-PCR combines specific antibody-based protein detection with the sensitivity of PCR-based quantification through the use of antibody-DNA conjugates. The production of such conjugates depends on the availability of quick and efficient conjugation strategies for the two biomolecules. Here, we present an approach to produce cleavable antibody-DNA conjugates, employing the fast kinetics of the inverse electron-demand Diels-Alder reaction between tetrazine and trans-cyclooctene (TCO). Our strategy consists of three steps. First, antibodies are functionalized with chemically cleavable NHS-s-s-tetrazine. Subsequently, double-stranded DNA is functionalized with TCO by enzymatic addition of N3-dATP and coupling to trans-Cyclooctene-PEG12-Dibenzocyclooctyne (TCO-PEG12-DBCO). Finally, conjugates are quickly and efficiently obtained by mixing the functionalized antibodies and dsDNA at low molar ratios of 1:2. In addition, introduction of a chemically cleavable disulphide linker facilitates release and sensitive detection of the dsDNA after immuno-staining. We show specific and sensitive protein detection in immuno-PCR for human epidermal stem cell markers, ITGA6 and ITGB1, and the differentiation marker Transglutaminase 1 (TGM1). We anticipate that the production of chemically cleavable antibody-DNA conjugates will provide a solid basis for the development of multiplexed immuno-PCR experiments and immuno-sequencing methodologies. PMID:26947912

  7. Manipulating fatty acid biosynthesis in microalgae for biofuel through protein-protein interactions.

    Directory of Open Access Journals (Sweden)

    Jillian L Blatti

    Full Text Available Microalgae are a promising feedstock for renewable fuels, and algal metabolic engineering can lead to crop improvement, thus accelerating the development of commercially viable biodiesel production from algae biomass. We demonstrate that protein-protein interactions between the fatty acid acyl carrier protein (ACP and thioesterase (TE govern fatty acid hydrolysis within the algal chloroplast. Using green microalga Chlamydomonas reinhardtii (Cr as a model, a structural simulation of docking CrACP to CrTE identifies a protein-protein recognition surface between the two domains. A virtual screen reveals plant TEs with similar in silico binding to CrACP. Employing an activity-based crosslinking probe designed to selectively trap transient protein-protein interactions between the TE and ACP, we demonstrate in vitro that CrTE must functionally interact with CrACP to release fatty acids, while TEs of vascular plants show no mechanistic crosslinking to CrACP. This is recapitulated in vivo, where overproduction of the endogenous CrTE increased levels of short-chain fatty acids and engineering plant TEs into the C. reinhardtii chloroplast did not alter the fatty acid profile. These findings highlight the critical role of protein-protein interactions in manipulating fatty acid biosynthesis for algae biofuel engineering as illuminated by activity-based probes.

  8. 125I-labeled protein A as a general tracer in immunoassay: suitability of goat and sheep antibodies

    International Nuclear Information System (INIS)

    The immunoassay method in which 125I-labeled staphylococcal Protein A ([125I]PA) serves as a general tracer has been extended to include goat and sheep IgG antibodies. Goat and sheep IgG normally do not react significantly with PA. However, once IgG antibody is bound to immobilized antigen or hapten, binding of [125I]PA is enhanced markedly. Binding efficiencies of [125I]PA to immune complexed goat anti-human IgM, human IgE, methotrexate and sheep anti-IgE were determined and compared quantitatively to rabbit IgG with the corresponding specificity. Immunoassays were developed based on the inhibition of [125I]PA binding as a measure of antibody inhibition by fluid-phase homologous ligand. Goat antibody to the monovalent hapten methotrexate behaved anomalously: for each concentration of IgG tested, there was an optimal amount of methotrexate beads that gave maximum binding of [125I]PA. In the other immune systems, for each antibody concentration maximum binding of tracer was a function only of the amount of immobilized anitgen added. In contrast to the results obtained with solid-phase antigen, solutions containing antibody and amounts of antigen ranging from large antigen excess to antibody excess failed to react significantly with PA or [125I]PA. (Auth.)

  9. Immunoproteomic Analysis of Antibody Responses to Extracellular Proteins of Candida albicans Revealing the Importance of Glycosylation for Antigen Recognition.

    Science.gov (United States)

    Luo, Ting; Krüger, Thomas; Knüpfer, Uwe; Kasper, Lydia; Wielsch, Natalie; Hube, Bernhard; Kortgen, Andreas; Bauer, Michael; Giamarellos-Bourboulis, Evangelos J; Dimopoulos, George; Brakhage, Axel A; Kniemeyer, Olaf

    2016-08-01

    During infection, the human pathogenic fungus Candida albicans undergoes a yeast-to-hypha transition, secretes numerous proteins for invasion of host tissues, and modulates the host's immune response. Little is known about the interplay of C. albicans secreted proteins and the host adaptive immune system. Here, we applied a combined 2D gel- and LC-MS/MS-based approach for the characterization of C. albicans extracellular proteins during the yeast-to-hypha transition, which led to a comprehensive C. albicans secretome map. The serological responses to C. albicans extracellular proteins were investigated by a 2D-immunoblotting approach combined with MS for protein identification. On the basis of the screening of sera from candidemia and three groups of noncandidemia patients, a core set of 19 immunodominant antibodies against secreted proteins of C. albicans was identified, seven of which represent potential diagnostic markers for candidemia (Xog1, Lip4, Asc1, Met6, Tsa1, Tpi1, and Prx1). Intriguingly, some secreted, strongly glycosylated protein antigens showed high cross-reactivity with sera from noncandidemia control groups. Enzymatic deglycosylation of proteins secreted from hyphae significantly impaired sera antibody recognition. Furthermore, deglycosylation of the recombinantly produced, secreted aspartyl protease Sap6 confirmed a significant contribution of glycan epitopes to the recognition of Sap6 by antibodies in patient's sera. PMID:27386892

  10. Atomic force microscopy-based antibody recognition imaging of proteins in the pathological deposits in Pseudoexfoliation Syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Creasey, Rhiannon [School of Chemical and Physical Sciences, Flinders University of SA, GPO Box 2100, Adelaide, SA 5001 (Australia); Sharma, Shiwani [School of Medicine, Ophthalmology, Flinders University of SA, GPO Box 2100, Adelaide, SA 5001 (Australia); Gibson, Christopher T. [School of Chemical and Physical Sciences, Flinders University of SA, GPO Box 2100, Adelaide, SA 5001 (Australia); Craig, Jamie E. [School of Medicine, Ophthalmology, Flinders University of SA, GPO Box 2100, Adelaide, SA 5001 (Australia); Ebner, Andreas [Institute for Biophysics, Johannes Kepler Universitaet Linz, Altenbergerstr. 69, A-4040 Linz (Austria); Becker, Thomas [Nanochemistry Research Institute, Curtin University, GPO Box U1987, Perth, 6845 WA (Australia); Hinterdorfer, Peter [Institute for Biophysics, Johannes Kepler Universitaet Linz, Altenbergerstr. 69, A-4040 Linz (Austria); Voelcker, Nicolas H., E-mail: nico.voelcker@flinders.edu.au [School of Chemical and Physical Sciences, Flinders University of SA, GPO Box 2100, Adelaide, SA 5001 (Australia)

    2011-07-15

    The phenomenon of protein aggregation is of considerable interest to various disciplines, including the field of medicine. A range of disease pathologies are associated with this phenomenon. One of the ocular diseases hallmarked by protein aggregation is the Pseudoexfoliation (PEX) Syndrome. This condition is characterized by the deposition of insoluble proteinaceous material on the anterior human lens capsule. Genomic and proteomic analyses have revealed an association of specific genetic markers and various proteins, respectively, with PEX syndrome. However, the ultrastructure of the protein aggregates is poorly characterized. This study seeks to build capacity to determine the molecular nature of PEX aggregates on human lens capsules in their native state by AFM-based antibody recognition imaging. Lysyl oxidase-Like 1 (LOXL1), a protein identified as a component of PEX aggregates, is detected by an antibody-modified AFM probe. Topographical AFM images and antibody recognition images are obtained using three AFM-based techniques: TREC, phase and force-volume imaging. LOXL1 is found to be present on the lens capsule surface, and is localized around fibrous protein aggregates. Our evaluation shows that TREC imaging is best suited for human tissue imaging and holds significant potential for imaging of human disease tissues in their native state. -- Highlights: {yields} Atomic force microscopy techniques were applied to diseased human tissues. {yields} LOXL1 protein was detected on the small fibers of Pseudoexfoliation deposits. {yields} PicoTREC was the optimum technique for investigating protein aggregates.

  11. Representation of protein-sequence information by amino acid subalphabets

    DEFF Research Database (Denmark)

    Andersen, C.A.F.; Brunak, Søren

    2004-01-01

    Within computational biology, algorithms are constructed with the aim of extracting knowledge from biological data, in particular, data generated by the large genome projects, where gene and protein sequences are produced in high volume. In this article, we explore new ways of representing protein......-sequence information, using machine learning strategies, where the primary goal is the discovery of novel powerful representations for use in AI techniques. In the case of proteins and the 20 different amino acids they typically contain, it is also a secondary goal to discover how the current selection of amino acids...

  12. Monoclonal antibody targeting chikungunya virus envelope 1 protein inhibits virus release.

    Science.gov (United States)

    Masrinoul, Promsin; Puiprom, Orapim; Tanaka, Atsushi; Kuwahara, Miwa; Chaichana, Panjaporn; Ikuta, Kazuyoshi; Ramasoota, Pongrama; Okabayashi, Tamaki

    2014-09-01

    Chikungunya virus (CHIKV) causes an acute clinical illness characterized by sudden high fever, intense joint pain, and skin rash. Recent outbreaks of chikungunya disease in Africa and Asia are a major public health concern; however, there is currently no effective licensed vaccine or specific treatment. This study reported the development of a mouse monoclonal antibody (MAb), CK47, which recognizes domain III within the viral envelope 1 protein and inhibited the viral release process, thereby preventing the production of progeny virus. The MAb had no effect on virus entry and replication processes. Thus, CK47 may be a useful tool for studying the mechanisms underlying CHIKV release and may show potential as a therapeutic agent.

  13. Monoclonal antibodies against proteins of the IBR virus nucleocapside and their assessing by ELISA

    Directory of Open Access Journals (Sweden)

    Jeannette Navarrete 0.

    2011-12-01

    Full Text Available Monoclonal antibodies were produced against the nucleocapside of a field IBR virus strain. The virus was growth in MOBK cell line. Viral components were purified and concentrated in a continuous 30% sacarose gradient followed by chemical precipitation. Nucleocapsides were run in a 10% SDS-PAGE gel. Positive hybridomes were tested using a direct ELISA developed in our laboratory. As a result eigth ELISA positive clones were obtained, from these five were also positive to seronetralization and immunodot. The clones recognize a 39.8Kda protein. Aditionally, a capture-ELISA was developed using the monoclonal antobodies from this research. This ELISA is useful to detect a reference as a field nm virus strain.

  14. The multiple roles of Fatty Acid Handling Proteins in brain

    Directory of Open Access Journals (Sweden)

    Valentine SF Moullé

    2012-09-01

    Full Text Available Lipids are essential components of a living organism as energy source but also as constituent of the membrane lipid bilayer. In addition fatty acid (FA derivatives interact with many signaling pathways. FAs have amphipathic properties and therefore require being associated to protein for both transport and intracellular trafficking. Here we will focus on several fatty acid handling proteins, among which the fatty acid translocase/CD36 (FAT/CD36, members of fatty acid transport proteins (FATPs, and lipid chaperones fatty acid-binding proteins (FABPs. A decade of extensive studies has helped decipher the mechanism of action of these proteins in peripheral tissue with high lipid metabolism. However, considerably less information is available regarding their role in the brain, despite the high lipid content of this tissue. This review will primarily focus on the recent studies that have highlighted the crucial role of lipid handling proteins in brain FA transport, neuronal differentiation and development, cognitive processes and brain diseases. Finally a special focus will be made on the recent studies that have revealed the role of FAT/CD36 in brain lipid sensing and nervous control of energy balance.

  15. Modifications of proteins by polyunsaturated fatty acid peroxidation products

    Science.gov (United States)

    Refsgaard, Hanne H. F.; Tsai, Lin; Stadtman, Earl R.

    2000-01-01

    The ability of unsaturated fatty acid methyl esters to modify amino acid residues in bovine serum albumin (BSA), glutamine synthetase, and insulin in the presence of a metal-catalyzed oxidation system [ascorbate/Fe(III)/O2] depends on the degree of unsaturation of the fatty acid. The fatty acid-dependent generation of carbonyl groups and loss of lysine residues increased in the order methyl linoleate < methyl linolenate < methyl arachidonate. The amounts of alkyl hydroperoxides, malondialdehyde, and a number of other aldehydes that accumulated when polyunsaturated fatty acids were oxidized in the presence of BSA were significantly lower than that observed in the absence of BSA. Direct treatment of proteins with various lipid hydroperoxides led to a slight increase in the formation of protein carbonyl derivatives, whereas treatment with the hydroperoxides together with Fe(II) led to a substantial increase in the formation of protein carbonyls. These results are consistent with the proposition that metal-catalyzed oxidation of polyunsaturated fatty acids can contribute to the generation of protein carbonyls by direct interaction of lipid oxidation products (α,β-unsaturated aldehydes) with lysine residues (Michael addition reactions) and also by interactions with alkoxyl radicals obtained by Fe(II) cleavage of lipid hydroperoxides that are formed. In addition, saturated aldehydes derived from the polyunsaturated fatty acids likely react with lysine residues to form Schiff base adducts.

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

    Science.gov (United States)

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

    2015-01-01

    The gene for the nucleocapsid (N) protein of canine distemper virus was cloned into the pMD-18T vector, and positive recombinant plasmids were obtained by enzyme digestion and sequencing. After digestion by both EcoRI and KpnI, the plasmid was directionally cloned into the eukaryotic expression vector pcDNA; the positive clone pcDNA-N was screened by electrophoresis and then transfected into COS-7 cells. Immunofluorescence analysis results showed that the canine distemper virus N protein was expressed in the cytoplasm of transfected COS-7 cells. After emulsification in Freund's adjuvant, the recombinant plasmid pcDNA-N was injected into the abdominal cavity of 8-week-old BABL/c mice, with the pcDNA original vector used as a negative control. Mice were immunized 3 times every 2 weeks. The blood of immunized mice was drawn 2 weeks after completing the immunizations to measure titer levels. The antibody titer in the pcDNA-N test was 10(1.62 ± 0.164), while in the control group this value was 10(0.52 ± 0.56), indicating that specific humoral immunity was induced in canine distemper virus nucleocapsid protein-immunized mice. PMID:25966074

  17. Recombinant nucleocapsid protein-based enzyme-linked immunosorbent assay for detection of antibody to turkey coronavirus.

    Science.gov (United States)

    Abdelwahab, Mohamed; Loa, Chien Chang; Wu, Ching Ching; Lin, Tsang Long

    2015-06-01

    Nucleocapsid (N) protein gene of turkey coronavirus (TCoV) was expressed in a prokaryotic system and used to develop an enzyme-linked immunosorbent assay (ELISA) for detection of antibody to TCoV. Anti-TCoV hyperimmune turkey serum and normal turkey serum were used as positive or negative controls for optimization of the ELISA. Goat anti-turkey IgG (H+L) conjugated with horseradish peroxidase was used as detector antibody. Three hundred and twenty two turkey sera from the field were used to evaluate the performance of ELISA and determine the cut-off point of ELISA. The established ELISA was also examined with serum samples obtained from turkeys experimentally infected with TCoV. Those serum samples were collected at various time intervals from 1 to 63 days post-infection. The optimum conditions for differentiation between anti-TCoV hyperimmune serum and normal turkey serum were recombinant TCoV N protein concentration at 20 μg/ml, serum dilution at 1:800, and conjugate dilution at 1:10,000. Of the 322 sera from the field, 101 were positive for TCoV by immunofluorescent antibody assay (IFA). The sensitivity and specificity of the ELISA relative to IFA test were 86.0% and 96.8%, respectively, using the optimum cut-off point of 0.2 as determined by logistic regression method. Reactivity of anti-rotavirus, anti-reovirus, anti-adenovirus, or anti-enterovirus antibodies with the recombinant N protein coated on the ELISA plates was not detected. These results indicated that the established antibody-capture ELISA in conjunction with recombinant TCoV N protein as the coating protein can be utilized for detection of antibodies to TCoV in turkey flocks.

  18. Chemical approaches to detect and analyze protein sulfenic acids.

    Science.gov (United States)

    Furdui, Cristina M; Poole, Leslie B

    2014-01-01

    Orchestration of many processes relying on intracellular signal transduction is recognized to require the generation of hydrogen peroxide as a second messenger, yet relatively few molecular details of how this oxidant acts to regulate protein function are currently understood. This review describes emerging chemical tools and approaches that can be applied to study protein oxidation in biological systems, with a particular emphasis on a key player in protein redox regulation, cysteine sulfenic acid. While sulfenic acids (within purified proteins or simple mixtures) are detectable by physical approaches like X-ray crystallography, nuclear magnetic resonance and mass spectrometry, the propensity of these moieties to undergo further modification in complex biological systems has necessitated the development of chemical probes, reporter groups and analytical approaches to allow for their selective detection and quantification. Provided is an overview of techniques that are currently available for the study of sulfenic acids, and some of the biologically meaningful data that have been collected using such approaches.

  19. Association of Levels of Antibodies from Patients with Inflammatory Bowel Disease with Extracellular Proteins of Food and Probiotic Bacteria

    Directory of Open Access Journals (Sweden)

    Arancha Hevia

    2014-01-01

    Full Text Available Inflammatory bowel disease (IBD is an autoimmune disease characterized by a chronic inflammation of the gastrointestinal tract mucosa and is related to an abnormal immune response to commensal bacteria. Our aim of the present work has been to explore the levels of antibodies (IgG and IgA raised against extracellular proteins produced by LAB and its association with IBD. We analyzed, by Western-blot and ELISA, the presence of serum antibodies (IgA and IgG developed against extracellular protein fractions produced by different food bacteria from the genera Bifidobacterium and Lactobacillus. We used a sera collection consisting of healthy individuals (HC, n=50, Crohn's disease patients (CD, n=37, and ulcerative colitis patients (UC, n=15. Levels of IgA antibodies developed against a cell-wall hydrolase from Lactobacillus casei subsp. rhamnosus GG (CWH were significantly higher in the IBD group (P<0.002; n=52. The specificity of our measurements was confirmed by measuring IgA antibodies developed against the CWH peptide 365-VNTSNQTAAVSAS-377. IBD patients appeared to have different immune response to food bacteria. This paper sets the basis for developing systems for early detection of IBD, based on the association of high levels of antibodies developed against extracellular proteins from food and probiotic bacteria.

  20. [Amino acid composition of rice grain proteins].

    Science.gov (United States)

    Peruanskiĭ, Iu V; Savich, I M

    1976-01-01

    The composition of the major reserve proteins of rice grain--globulins, prolamines and glutelins--was examined in four rice varieties (Dubovsky 129, Kuban 3, Alakul, Ushtobinsky). Globulins proved to be most heterogeneous whereas glutelins appeared to be least heterogeneous. In regards to the ratio of components globulins showed high variability and glutelins displayed high stability. PMID:1005365

  1. Conditional expression of full-length humanized anti-prion protein antibodies in Chinese hamster ovary cells.

    Science.gov (United States)

    Mueller, Daniel A; Heinig, Lars; Ramljak, Sanja; Krueger, Astrid; Schulte, Reiner; Wrede, Arne; Stuke, Andreas W

    2010-12-01

    Because of their high antigen specificity and metabolic stability, genetically engineered human monoclonal antibodies are on the way to becoming one of the most promising medical diagnostics and therapeutics. In order to establish an in vitro system capable of producing such biosimilar antibodies, we used human constant chain sequences to design the novel human antibody expressing vector cassette pMAB-ABX. A bidirectional tetracycline (tet)-controllable promotor was used for harmonized expression of immunoglobulin type G (IgG) heavy and light chains. As an example we used anti-prion protein (anti-PrP) IgGs. Therefore, the variable heavy (V(H)) and light chain (V(L)) sequences of anti-PrP antibodies, previously generated in our laboratory by DNA immunization of prion protein knock-out mice, were isolated from murine hybridoma cell lines and inserted into pMAB-ABX vector. After transfection of Chinese hamster ovary (CHO) cells, a number of stable antibody producing cell clones were selected. One cell line (pMAB-ABX-13F10/3B5) stably expressing the recombinant humanized antibody (rechuAb) 13F10/3B5 was selected for detailed characterization by Western blot, immunofluorescence, and flow cytometric analyses. The full-length recombinant humanized IgG antibody showed a high level of expression in the cytoplasm. In conclusion, the new cell system described here is a suitable tool to produce functional intact full-length humanized IgG antibodies. PMID:21087094

  2. Hypervariable antigenic region 1 of classical swine fever virus E2 protein impacts antibody neutralization.

    Science.gov (United States)

    Liao, Xun; Wang, Zuohuan; Cao, Tong; Tong, Chao; Geng, Shichao; Gu, Yuanxing; Zhou, Yingshan; Li, Xiaoliang; Fang, Weihuan

    2016-07-19

    Envelope glycoprotein E2 of classical swine fever virus (CSFV) is the major antigen that induces neutralizing antibodies and confers protection against CSFV infection. There are three hypervariable antigenic regions (HAR1, HAR2 and HAR3) of E2 that are different between the group 1 vaccine C-strain and group 2 clinical isolates. This study was aimed to characterize the antigenic epitope region recognized by monoclonal antibody 4F4 (mAb-4F4) that is present in the group 2 field isolate HZ1-08, but not in the C-strain, and examine its impact on neutralization titers when antisera from different recombinant viruses were cross-examined. Indirect ELISA with C-strain E2-based chimeric proteins carrying the three HAR regions showed that the mAb-4F4 bound to HAR1 from HZ1-08 E2, but not to HAR2 or HAR3, indicating that the specific epitope is located in the HAR1 region. Of the 6 major residues differences between C-strain and field isolates, Glu713 in the HAR1 region of strain HZ1-08 is critical for mAb-4F4 binding either at the recombinant protein level or using intact recombinant viruses carrying single mutations. C-strain-based recombinant viruses carrying the most antigenic part of E2 or HAR1 from strain HZ1-08 remained non-pathogenic to pigs and induced good antibody responses. By cross-neutralization assay, we observed that the anti-C-strain serum lost most of its neutralization capacity to RecC-HZ-E2 and QZ-14 (subgroup 2.1d field isolate in 2014), and vice versa. More importantly, the RecC-HAR1 virus remained competent in neutralizing ReC-HZ-E2 and QZ-14 strains without compromising the neutralization capability to the recombinant C-strain. Thus, we propose that chimeric C-strain carrying the HAR1 region of field isolates is a good vaccine candidate for classical swine fever. PMID:27317266

  3. Nucleic acid compositions and the encoding proteins

    Science.gov (United States)

    Preston, III, James F.; Chow, Virginia; Nong, Guang; Rice, John D.; St. John, Franz J.

    2014-09-02

    The subject invention provides at least one nucleic acid sequence encoding an aldouronate-utilization regulon isolated from Paenibacillus sp. strain JDR-2, a bacterium which efficiently utilizes xylan and metabolizes aldouronates (methylglucuronoxylosaccharides). The subject invention also provides a means for providing a coordinately regulated process in which xylan depolymerization and product assimilation are coupled in Paenibacillus sp. strain JDR-2 to provide a favorable system for the conversion of lignocellulosic biomass to biobased products. Additionally, the nucleic acid sequences encoding the aldouronate-utilization regulon can be used to transform other bacteria to form organisms capable of producing a desired product (e.g., ethanol, 1-butanol, acetoin, 2,3-butanediol, 1,3-propanediol, succinate, lactate, acetate, malate or alanine) from lignocellulosic biomass.

  4. Development of Polyclonal Antibodies for the Detection of Styrene Oxide Modified Proteins

    OpenAIRE

    Yuan, Wei; Chung, Jouku; Gee, Shirley; Bruce D Hammock; Zheng, Jiang

    2007-01-01

    Styrene is widely used as one of the most important industrial materials for the production of synthetic rubbers, plastic, insulation, fiberglass, and automobile parts. Inhaled styrene has been reported to produce respiratory toxicity in humans and animals. Styrene oxide, a reactive metabolite of styrene formed via cytochrome P450 enzymes, has been reported to form covalent bonds with proteins, such as albumin and hemoglobin. Among all of the amino acids, cysteine is the most reactive amino a...

  5. Synthetic LNA/DNA nano-scaffolds for highly efficient diagnostics of nucleic acids and autoimmune antibodies

    DEFF Research Database (Denmark)

    Astakhova, Irina Kira

    2014-01-01

    Herein novel fluorescent oligonucleotides for homogeneous (all-in-solution) detection of nucleic acids and autoimmune antibodies (autoantibodies) are described. The probes are prepared by highly efficient copper-catalyzed click chemistry between novel alkyne-modified locked nucleic acid (LNA...... of the monoclonal human autoantibody is achieved. It makes the novel "clickable" LNA/DNA complexes a very promising tool in molecular diagnostics of both nucleic acids and autoantibodies against DNA. The latter are produced under several autoimmune conditions including antiphospholipide syndrome and systemic lupus...

  6. ENZYME DIGEST AND ACID HYDROLYZED INDEX OF PROTEIN QUALITY EVALUATION

    Directory of Open Access Journals (Sweden)

    H.Mohammadiha P. Mostafavi

    1984-08-01

    Full Text Available A pancreatopeptidase (Elastase digest index was devised for a rapid and accurate estimation of protein quality. This index was calculated on the basis of all the amino acids released by an in-vitro Elastase digestion, acid hydrolyses of same sample and the residue of enzyme hydrolyzed. The amino acids were determined by Thin-Layer Chromatography. Samples used were cooked white kidneybeans, cooked and over-heated soybean powder, and skimmed milk powder. Good correlation was observed between elastase index value and their biological values reported in the literature from feeding trials. The pattern of aminoacids released by acid and by enzyme hydrolysis was about the same.

  7. Non-protein amino acids in peptide design

    Indian Academy of Sciences (India)

    S Aravinda; N Shamala; Rituparna S Roy; P Balaram

    2003-10-01

    An overview of the use of non-protein amino acids in the design of conformationally well-defined peptides, based on work from the author’s laboratory, is discussed. The crystal structures of several designed oligopeptides illustrate the use -aminoisobutyric acid (Aib) in the construction of helices, D-amino acids in the design of helix termination segments and DPro-Xxx segments for nucleating of -hairpin structures. - and -amino acid residues have been used to expand the range of designed polypeptide structures.

  8. OX133, a monoclonal antibody recognizing protein-bound N-ethylmaleimide for the identification of reduced disulfide bonds in proteins.

    Science.gov (United States)

    Holbrook, Lisa-Marie; Kwong, Lai-Shan; Metcalfe, Clive L; Fenouillet, Emmanuel; Jones, Ian M; Barclay, A Neil

    2016-01-01

    In vivo, enzymatic reduction of some protein disulfide bonds, allosteric disulfide bonds, provides an important level of structural and functional regulation. The free cysteine residues generated can be labeled by maleimide reagents, including biotin derivatives, allowing the reduced protein to be detected or purified. During the screening of monoclonal antibodies for those specific for the reduced forms of proteins, we isolated OX133, a unique antibody that recognizes polypeptide resident, N-ethylmaleimide (NEM)-modified cysteine residues in a sequence-independent manner. OX133 offers an alternative to biotin-maleimide reagents for labeling reduced/alkylated antigens and capturing reduced/alkylated proteins with the advantage that NEM-modified proteins are more easily detected in mass spectrometry, and may be more easily recovered than is the case following capture with biotin based reagents. PMID:26986548

  9. Canine Antibodies against Salivary Recombinant Proteins of Phlebotomus perniciosus: A Longitudinal Study in an Endemic Focus of Canine Leishmaniasis.

    Directory of Open Access Journals (Sweden)

    Tatiana Kostalova

    Full Text Available Phlebotomine sand flies are vectors of Leishmania parasites. During blood feeding, sand flies deposit into the host skin immunogenic salivary proteins which elicit specific antibody responses. These anti-saliva antibodies enable an estimate of the host exposure to sand flies and, in leishmaniasis endemic areas, also the risk for Leishmania infections. However, the use of whole salivary gland homogenates as antigen has several limitations, and therefore, recombinant salivary proteins have been tested to replace them in antibody detection assays. In this study, we have used for the first time sand fly salivary recombinant proteins in a longitudinal field study on dogs.Sera from dogs naturally exposed to P. perniciosus bites over two consecutive transmission seasons in a site endemic for canine leishmaniasis (CanL were tested at different time points by ELISA for the antibodies recognizing whole saliva, single salivary 43 kDa yellow-related recombinant protein (rSP03B, and a combination of two salivary recombinant proteins, 43 kDa yellow-related protein and 35.5 kDa apyrase (rSP01. Dogs were also tested for Leishmania infantum positivity by serology, culture, and PCR and the infection status was evaluated prospectively. We found a significant association between active CanL infection and the amount of anti-P. perniciosus saliva antibodies. Importantly, we detected a high correlation between IgG antibodies recognizing rSP03B protein and the whole salivary antigen. The kinetics of antibody response showed for both a whole saliva and rSP03B a similar pattern that was clearly related to the seasonal abundance of P. perniciosus.These results suggest that P. perniciosus rSP03B protein is a valid alternative to whole saliva and could be used in large-scale serological studies. This novel method could be a practical and economically-sound tool to detect the host exposure to sand fly bites in CanL endemic areas.

  10. FLU, an amino acid substitution model for influenza proteins

    Directory of Open Access Journals (Sweden)

    Gascuel Olivier

    2010-04-01

    Full Text Available Abstract Background The amino acid substitution model is the core component of many protein analysis systems such as sequence similarity search, sequence alignment, and phylogenetic inference. Although several general amino acid substitution models have been estimated from large and diverse protein databases, they remain inappropriate for analyzing specific species, e.g., viruses. Emerging epidemics of influenza viruses raise the need for comprehensive studies of these dangerous viruses. We propose an influenza-specific amino acid substitution model to enhance the understanding of the evolution of influenza viruses. Results A maximum likelihood approach was applied to estimate an amino acid substitution model (FLU from ~113, 000 influenza protein sequences, consisting of ~20 million residues. FLU outperforms 14 widely used models in constructing maximum likelihood phylogenetic trees for the majority of influenza protein alignments. On average, FLU gains ~42 log likelihood points with an alignment of 300 sites. Moreover, topologies of trees constructed using FLU and other models are frequently different. FLU does indeed have an impact on likelihood improvement as well as tree topologies. It was implemented in PhyML and can be downloaded from ftp://ftp.sanger.ac.uk/pub/1000genomes/lsq/FLU or included in PhyML 3.0 server at http://www.atgc-montpellier.fr/phyml/. Conclusions FLU should be useful for any influenza protein analysis system which requires an accurate description of amino acid substitutions.

  11. Antibody-free, targeted mass-spectrometric approach for quantification of proteins at low picogram per milliliter levels in human plasma/serum

    OpenAIRE

    Shi, Tujin; Fillmore, Thomas L.; Sun, Xuefei; Zhao, Rui; Schepmoes, Athena A.; Hossain, Mahmud; Xie, Fang; Wu, Si; Kim, Jong-Seo; Jones, Nathan; Moore, Ronald J.; Paša-Tolić, Ljiljana; Kagan, Jacob; Rodland, Karin D.; Liu, Tao

    2012-01-01

    Sensitive detection of low-abundance proteins in complex biological samples has typically been achieved by immunoassays that use antibodies specific to target proteins; however, de novo development of antibodies is associated with high costs, long development lead times, and high failure rates. To address these challenges, we developed an antibody-free strategy that involves PRISM (high-pressure, high-resolution separations coupled with intelligent selection and multiplexing) for sensitive se...

  12. Cloning and characterization of a complementary deoxyribonucleic acid encoding haploid-specific alanine-rich acidic protein located on chromosome-X.

    Science.gov (United States)

    Uchida, K; Tsuchida, J; Tanaka, H; Koga, M; Nishina, Y; Nozaki, M; Yoshinaga, K; Toshimori, K; Matsumiya, K; Okuyama, A; Nishimune, Y

    2000-10-01

    We have isolated a cDNA clone encoding a germ cell-specific protein from an expression cDNA library prepared from the mouse testis using testis-specific polyclonal antibodies. Northern blot analysis showed a transcript of 1.1 kilobases exclusively expressed in haploid germ cells of the testis. Sequence analysis of the cDNA revealed one long open reading frame consisting of 238 deduced amino acids, rich in basic amino acids in the N-terminal one-third that also contained the nuclear localization signal, and rich in acidic amino acids, including two type of acidic alanine-rich repeats, in the rest of the deduced protein. The protein having a molecular weight of approximately 55 kDa and an isoelectric point of pH 4.3-4.7 was also exclusively detected in the testis by Western blot analysis. As the cDNA was located on chromosome-X, Halap-X (haploid-specific alanine-rich acidic protein located on chromosome-X) was proposed for the name of the protein encoded by the cDNA. Immunohistochemical observation revealed that the Halap-X protein was predominantly present in the nucleoplasm of round spermatids but gradually decreased as spermatids matured, followed by the subsequent appearance in the cytoplasm of elongating spermatids. Thus, the Halap-X protein was transferred from the nuclei to the cytoplasm during the spermatid maturation when the chromatin condensation and transformation of the nuclei occurred. The Halap-X may facilitate specific association of nuclear DNA with some basic chromosomal proteins and play important roles in the process of chromatin condensation. PMID:10993819

  13. Development of polyclonal antibodies for detection of aflatoxigenic molds involving culture filtrate and chimeric proteins expressed in Escherichia coli.

    Science.gov (United States)

    Shapira, R; Paster, N; Menasherov, M; Eyal, O; Mett, A; Meiron, T; Kuttin, E; Salomon, R

    1997-03-01

    Polyclonal antibodies (PAb) were raised against an aflatoxigenic strain of Aspergillus parasiticus by using two different sources for antibody elicitation: (i) filtrate of a culture on which the fungus had been grown (ii) and two chimeric proteins, expressed in Escherichia coli as separate products, of the genes ver-1 and apa-2, which are involved in aflatoxin biosynthesis. The gene products were amplified by PCR, and each was cloned into the E. coli expression vector pGEX2T. Upon induction, the bacteria overexpressed 38- and 33-kDa chimeric proteins corresponding to the N-terminal domains of the genes ver-1 and apa-2, respectively. The chimeric proteins were isolated and affinity purified for use as antigens. The specificity of the raised antibodies was examined by enzyme-linked immunosorbent assay (ELISA). The PAbs raised against the culture filtrate reacted with all the species of Aspergillus and Penicillium tested but not with Fusarium species or corn gain. However, the PAbs elicited against the chimeric proteins were highly specific, showing significantly higher ELISA absorbance values (A405) against A. parasiticus and A. flavus than against the other fungi tested and the corn grain. The approach of utilizing gene products associated with aflatoxin biosynthesis for antibody production therefore appears to be feasible. Such a multiantibody system combined with the PCR technique, could provide a useful tool for the rapid, sensitive, and accurate detection of aflatoxin producers present in grains and foods. PMID:9055416

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

    NARCIS (Netherlands)

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

    1987-01-01

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

  15. Expression, purification of herpes simplex virus type 1 US11 Protein, and production of US11 polyclonal antibody

    OpenAIRE

    Yao Shanglong; Wuyunerdeni,; Huang Yizhong

    2011-01-01

    Abstract Background The US11 protein of herpes simplex virus type 1 (HSV-1) is a small, highly basic phosphoprotein expressed at late times during infection. To date, the function of US11 protein in cell culture and animal models is poorly understood. To further investigate the function of the US11 protein, this study was undertaken to express the US11 protein and raise a polyclonal antibody. Results The US11 gene was cloned into the prokaryotic expression vector pET-32a (+) to express His-ta...

  16. Reaction of Native and Denatured Brucella abortus (S19 Proteins with Antibody Using Affinity Chromatography and Immunoblotting

    Directory of Open Access Journals (Sweden)

    R. Karimi

    2005-01-01

    Full Text Available Western blotting or immunoblotting commonly use for study of reaction between antigens and antibodies. Denaturation of many proteins in immunoblotting can affect greatly the reactivity of antibodies and outcome of the procedure.In this study proteins of Brucella abortus (S19 was extracted by a mild method and reaction of the extracted proteins with serum of infected human and goat and immunized rabbit compared by affinity chromatography and immunoblotting. Gamma globulin (mostly IgG fraction of the sera was precipitated by half saturation of ammonium sulfate and linked to activated sepharose 4B. The extracted proteins were loaded on the affinity column. Attached proteins was eluted by low pH and analyzed by SDS-PAGE. Reaction of the total extract and eluted fractions with IgG fraction of sera was evaluated by Western blotting.Upon the results of affinity chromatography and immunoblotting, Brucella proteins can be classified in four groups: 1- The proteins that adsorbed to the affinity column and react with IgG in westernblotting. 2- Proteins that react with IgG in native state but no in denatured state. 3- Proteins that do not react with IgG in native state but react in denatured state. 4- Proteins that do not react with IgG in native and denatured state.

  17. Interference of peptides and specific antibodies with the function of the Actinobacillus pleuropneumoniae transferrin-binding protein.

    OpenAIRE

    Strutzberg, K; Franz, B.; Gerlach, G F

    1997-01-01

    Multiple-antigenic peptides (MAPs) containing transferrin-binding domains of the Actinobacillus pleuropneumoniae serotype 7-derived transferrin-binding protein (TfbA) (K. Strutzberg, L. von Olleschik, B. Franz, C. Pyne, M. A. Schmidt, and G.-F. Gerlach, Infect. Immun. 63:3846-3850, 1995) were constructed. It was found that the MAPs inhibited transferrin binding of the recombinant TfbA protein, whereas antibodies directed against transferrin-binding domains failed to do so.

  18. Discovery and validation of an INflammatory PROtein-driven GAstric cancer Signature (INPROGAS) using antibody microarray-based oncoproteomics

    OpenAIRE

    Puig-Costa, Manuel; Codina-Cazador, Antonio; Cortés-Pastoret, Elisabet; Oliveras-Ferraros, Cristina; Cufí, Sílvia; Flaquer, Sílvia; Llopis-Puigmarti, Francesca; Pujol-Amado, Eulalia; Corominas-Faja, Bruna; Cuyàs, Elisabet; Ortiz, Rosa; Lopez-Bonet, Eugeni; Queralt, Bernardo; Guardeño, Raquel; Martin-Castillo, Begoña

    2014-01-01

    This study aimed to improve gastric cancer (GC) diagnosis by identifying and validating an INflammatory PROtein-driven GAstric cancer Signature (hereafter INPROGAS) using low-cost affinity proteomics. The detection of 120 cytokines, 43 angiogenic factors, 41 growth factors, 40 inflammatory factors and 10 metalloproteinases was performed using commercially available human antibody microarray-based arrays. We identified 21 inflammation-related proteins (INPROGAS) with significant differences in...

  19. Protein expression and preparation of polydonal antibody of AD-004 and study on its expression in the adrenal and testis

    Institute of Scientific and Technical Information of China (English)

    乔洁

    2006-01-01

    Objective To prepare rabbit antibody against mouse AD-004 by AD-004 expressed in the prokaryotic expression system and to identify its distribution in the testis and adrenal. Methods The full-length cDNA of mouse AD-004 was cloned into PET28 plasmid, and the protein was induced in E. coli BL21 bacteria by adding IPTG and then purified by Ni2+ -NTA column. The purified protein was used as an immunogene to prepare polyclonal

  20. [Fractional and amino acid composition of krill proteins and the potential for obtaining protein preparations].

    Science.gov (United States)

    Orlova, T A; Churina, E E; Kuranova, L K

    1985-01-01

    Studies of the fractional composition of krill proteins demonstrated that the content of protein fractions changes depending on the time of krill catch. The highest amount of water-soluble proteins is contained by krill caught in December (64%), of salt-soluble by krill caught in June (12%), base-soluble by krill caught in May, September and February (34%). Krill protein contains from 50 to 60% of water- and salt-soluble fractions. Analysis of the amino acid composition of krill proteins showed that it does not differ essentially from that of adequate food proteins.

  1. Optimisation of hybridoma cell growth and monoclonal antibody secretion in a chemically defined, serum- and protein-free culture medium.

    Science.gov (United States)

    Schneider, Y J

    1989-01-01

    Monoclonal antibodies (MAbs), for human use require chemical and biological purity. The best approach seems in vitro cultivation in a serum-, protein-free medium. A basal defined culture medium has been developed to sustain optimal hybridoma cell growth and MAb secretion. It consists of Iscove's Dulbecco's modified, Eagle's, Ham's F12 and NCTC 135 media in a 5:5:1 mixture (v/v/v), to which glucose is added to reach a final concentration of 25 mM, glutamine to 4-6 mM, 2-mercaptoethanol to 50 microM, Pluronic F68 to 0.01-0.1% (w/v), Hepes to 25 mM and NaHCO3 to 3 g/l. Hybridoma cells, derived from Sp 2/0 myeloma and secreting a MAb to a human milk fat globule membrane-associated high molecular weight glycoprotein, were cloned in this medium containing 1% (v/v) fetal calf serum and then sequentially adapted in serum-free medium further supplemented with transferrin and insulin, both at 10 micrograms/ml. Clones producing immunoreactive MAbs secrete a mean of 50 micrograms IgG/ml, i.e., ca. 80% of the concentration reached in Dulbecco's modified Eagle's medium containing 10% serum. When cells were cultured in spinner flasks with a semi-continuous mode of cultivation (with a daily removal of 20% of the volume and its replacement by fresh culture medium), in serum-free medium further supplemented with 10 nM estradiol, a mixture of trace elements and albumin (at 30 micrograms/ml) complexed to linoleic acid, MAb secretion reached 100 micrograms/ml and became equal or higher to that obtained in serum-containing medium. MAb secretion was not decreased and was even significantly increased during the growth phase, when transferrin was replaced by another iron source, i.e., ferric citrate at 500 microM associated with 20 microM ascorbic acid. Finally, deletion of insulin and of albumin-linoleic acid did not affect significantly cell density nor MAb secretion. In conclusion, it appears from this study that semi-continuous cultivation in spinner flasks of hybridoma cells, after

  2. Effects of the Sheep Polyclonal Antibodies Against the Porcine Adipocyte Plasma Membrane Proteins on Porcine Carcass Composition and Meat Quality

    Institute of Scientific and Technical Information of China (English)

    GAO Shi-zheng; HU Hong-mei; LIU Ling-yun; ZHANG Xi; LIU Yong-gang; GE Chang-rong

    2007-01-01

    To detect the effects of the polyclonal antibodies raised in sheep against porcine adipocyte plasma membranes on the porcine carcass composition and meat quality, 30 pigs assigned into 6 treatment groups were given intraperitoneal injections of sheep antipig adipocyte plasma membrane immunoglobulin (ASIg) or sheep nonimmune serum immunoglobulin (NSIg). At the end of the experiment, the pigs were slaughtered at 90 kg body weight, and carcasses and meat quality were evaluated. The results showed that when pigs intraperitoneally immunized with 20 or 30 mg ASIg at 15 kg body weight, 20 mg purified ASIg twice at 15 and 60 kg body weight, or 20 mg purified ASIg at 60 kg body weight, respectively, their lean meat percentage, fat meat percentage, backfat thickness, loin eye area leaf fat weight, caul fat weight, heart weight, liver weight, and kidney weight were significantly affected. However, the kidney weight, lung weight, dressing percentage,and spleen weight did not remarkably change. Our results indicated that pigs intraperitoneally immunized with 20 or 30 mg ASIg at 15 kg body weight, and 20 mg ASIg twice at 15 and 60 kg body weight, have significantly different drip loss rate,cooked meat ratio, tenderness, storage loss rate, muscle fiber diameter, moisture content, dry matter content, crude protein content, and crude fat content from the control group that received 20 mg NSIg at 15 kg body weight. However, meat pH,meat color value, meat marbling score, inosinate, and myohemoglobin were not significantly affected. Our results indicated ASIg could not significantly affect the content of most muscular amino acids and intramuscular fatty acids.

  3. 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.

  4. CONTENTS OF SERUM MYELIN BASIC PROTEIN-IGG ANTIBODIES COMPLEXES IN NORMAL PREGNANCY AND GESTOSIS

    Directory of Open Access Journals (Sweden)

    V. G. Levchenko

    2010-01-01

    Full Text Available Serum levels of myelin basic protein (MBP-bound immune complexes were studied in blood sera from women with gestosis, as compared with those in normal pregnancy and non-pregnant woman. The amounts of IgG-MBP complex in blood serum were determined by enzyme immunoassay using isolated anti-МBP-antibodies. The study has shown that about 0.05 mcg of IgG ml of blood serum are associated with myelin basic protein in unpregnant women or in normal pregnancy. Mild gestosis is accompanied by a 2-3-fold increase in MBP immunocomplex concentrations in blood serum. More severe stages of gestosis are characterized by its further rise, thus achieving maximal values of such MBP immune complexes (0.8 mcg/ml in patients with pre-eclampsia and eclampsia. Their amounts were reduced twice after the periods of eclampsia. Serum levels of MBP-bound IgGs may be used to determine severity of gestosis and to predict a risk of eclampsia in pregnant women.

  5. Monoclonal antibody-based immunoenzymometric assays of retinol-binding protein.

    Science.gov (United States)

    Pereira, A B; Nishida, S K; Vieira, J G; Lombardi, M T; Silva, M S; Ajzen, H; Ramos, O L

    1993-03-01

    Retinol-binding protein (RBP) is a low-molecular-mass protein (21 kDa), easily filtered in renal glomeruli and very efficiently reabsorbed by the proximal convoluted tubules (PCTs). In PCT dysfunction, high concentrations of RBP are found in urine. Several methods have been used to determine RBP in serum or urine. We describe the production, selection, labeling, and utilization of anti-RBP monoclonal antibodies in two- or one-step immunoenzymometric assays for the determination of RBP. The one-step assay has good precision, with within-run and between-run CVs < 6.6% and 5.9%, respectively. Comparison with radial immunodiffusion (x) showed good agreement: y = 0.068 mg/L + 0.899x (n = 24). Comparison between the one-step (y) and two-step (x) versions of the assay also showed a very good correlation: y = 212 micrograms/L + 0.910x. The one-step assay has been adopted for routine work; it detects transthyretin-bound as well as free RBP and may have clinical usefulness in evaluating the functional status of PCTs. PMID:8448859

  6. Affinity binding of antibodies to supermacroporous cryogel adsorbents with immobilized protein A for removal of anthrax toxin protective antigen.

    Science.gov (United States)

    Ingavle, Ganesh C; Baillie, Les W J; Zheng, Yishan; Lis, Elzbieta K; Savina, Irina N; Howell, Carol A; Mikhalovsky, Sergey V; Sandeman, Susan R

    2015-05-01

    Polymeric cryogels are efficient carriers for the immobilization of biomolecules because of their unique macroporous structure, permeability, mechanical stability and different surface chemical functionalities. The aim of the study was to demonstrate the potential use of macroporous monolithic cryogels for biotoxin removal using anthrax toxin protective antigen (PA), the central cell-binding component of the anthrax exotoxins, and covalent immobilization of monoclonal antibodies. The affinity ligand (protein A) was chemically coupled to the reactive hydroxyl and epoxy-derivatized monolithic cryogels and the binding efficiencies of protein A, monoclonal antibodies to the cryogel column were determined. Our results show differences in the binding capacity of protein A as well as monoclonal antibodies to the cryogel adsorbents caused by ligand concentrations, physical properties and morphology of surface matrices. The cytotoxicity potential of the cryogels was determined by an in vitro viability assay using V79 lung fibroblast as a model cell and the results reveal that the cryogels are non-cytotoxic. Finally, the adsorptive capacities of PA from phosphate buffered saline (PBS) were evaluated towards a non-glycosylated, plant-derived human monoclonal antibody (PANG) and a glycosylated human monoclonal antibody (Valortim(®)), both of which were covalently attached via protein A immobilization. Optimal binding capacities of 108 and 117 mg/g of antibody to the adsorbent were observed for PANG attached poly(acrylamide-allyl glycidyl ether) [poly(AAm-AGE)] and Valortim(®) attached poly(AAm-AGE) cryogels, respectively, This indicated that glycosylation status of Valortim(®) antibody could significantly increase (8%) its binding capacity relative to the PANG antibody on poly(AAm-AGE)-protien-A column (p < 0.05). The amounts of PA which remained in the solution after passing PA spiked PBS through PANG or Valortim bound poly(AAm-AGE) cryogel were significantly (p < 0

  7. Nano-Magnetic Immunosensor Based on Staphylococcus Protein A and the Amplification Effect of HRP-Conjugated Phage Antibody

    Directory of Open Access Journals (Sweden)

    Xihui Mu

    2015-02-01

    Full Text Available In this research, super-paramagnetic Fe3O4 nanoparticles (magnetic particles were coated with Staphylococcus protein A (SPA and coupled with polyclonal antibody (pcAb to construct magnetic capturing probes, and HRP-conjugated phage antibody was then used as specific detecting probe to design a labeled immunosensor for trace detection of Staphylococcus aureus enterotoxin B (SEB. The linear detection range of the sensor was 0.008~125 µg/L, the regression equation was Y = 0.487X + 1.2 (R = 0.996, N = 15, p < 0.0001, the limit of detection (LOD was 0.008 µg/L, and the limit of quantification (LOQ was 0.008 µg/L. HRP-conjugated phage antibody, SPA and magnetic particles can enhance the sensitivity 4-fold, 3-fold and 2.6-fold higher, respectively. Compared with conventional double-antibody sandwich ELISA, the detection sensitivity of the sensor was 31-fold higher resulting from the integrated amplifying effect. The immunosensor integrates the unique advantages of SPA-oriented antibody as magnetic capturing probe, HRP-conjugated phage antibody as detecting probe, magnetic separation immunoassay technique, and several other advanced techniques, so it achieves high sensitivity, specificity and interference-resistance. It is proven to be well suited for analysis of trace SEB in various environmental samples with high recovery rate and reproducibility.

  8. Proteins, Peptides and Amino Acids: Role in Infant Nutrition.

    Science.gov (United States)

    Nutten, Sophie

    2016-01-01

    Proteins are polymers composed of 30 or more amino acids; some of them are essential dietary components, since they are not synthetized by human metabolic processes. They are crucial for healthy growth and development and influence major functions of the body. The infant's first year is a critical time of rapid growth and development, which must be supported by a high rate of protein synthesis. Breast milk, as a single specific food source in the first months of life, is providing the total protein and essential amino acids required. Infant formulas have been designed for infants who cannot be breastfed. They should be similar to breast milk in their composition and their functional outcomes, insuring appropriate growth, optimal development, maturation of the immune system, easy digestion and healthy metabolic programming. By modifying their protein components, specific infant formulas have also been developed for specific needs. For example, partially hydrolyzed (prevention of atopic dermatitis) and extensively hydrolyzed or amino-acid-based infant formulas (reduction in allergy symptoms) have been designed for the management of cow's milk protein allergy. In conclusion, proteins provided via breast milk or infant formula are essential components of the infant's diet; therefore, the specific quality, quantity and conformation of proteins are of utmost importance for healthy growth and development.

  9. Proteins, Peptides and Amino Acids: Role in Infant Nutrition.

    Science.gov (United States)

    Nutten, Sophie

    2016-01-01

    Proteins are polymers composed of 30 or more amino acids; some of them are essential dietary components, since they are not synthetized by human metabolic processes. They are crucial for healthy growth and development and influence major functions of the body. The infant's first year is a critical time of rapid growth and development, which must be supported by a high rate of protein synthesis. Breast milk, as a single specific food source in the first months of life, is providing the total protein and essential amino acids required. Infant formulas have been designed for infants who cannot be breastfed. They should be similar to breast milk in their composition and their functional outcomes, insuring appropriate growth, optimal development, maturation of the immune system, easy digestion and healthy metabolic programming. By modifying their protein components, specific infant formulas have also been developed for specific needs. For example, partially hydrolyzed (prevention of atopic dermatitis) and extensively hydrolyzed or amino-acid-based infant formulas (reduction in allergy symptoms) have been designed for the management of cow's milk protein allergy. In conclusion, proteins provided via breast milk or infant formula are essential components of the infant's diet; therefore, the specific quality, quantity and conformation of proteins are of utmost importance for healthy growth and development. PMID:27336588

  10. Affects of N-terminal variation in the SeM protein of Streptococcus equi on antibody and fibrinogen binding.

    Science.gov (United States)

    Timoney, John F; DeNegri, Rafaela; Sheoran, Abhineet; Forster, Nathalie

    2010-02-10

    The clonal Streptococcus equi causes equine strangles, a highly contagious suppurative lymphadenopathy and rhinopharyngitis. An important virulence factor and vaccine component, the antiphagocytic fibrinogen binding SeM of S. equi is a surface anchored fibrillar protein. Two recent studies of N. American, Japanese and European isolates have revealed a high frequency of N-terminal amino acid variation in SeM of S. equi CF32 that suggests this region of the protein is subject to immunologic selection pressure. The aims of the present study were firstly to map regions of SeM reactive with convalescent equine IgG and IgA and stimulatory for lymph node cells and secondly to determine effects of N-terminal variation on the functionality of SeM. Variation did not significantly affect fibrinogen binding or susceptibility of S. equi to an opsonic equine serum. Linear epitopes reactive with convalescent IgG and mucosal IgA were concentrated toward the conserved center of SeM. However, IgA but not IgG from every horse reacted with at least one peptide that contained variable sequence. Lymph node cells (CD4+) from horses immunized with SeM were strongly responsive to a peptide (alphaalpha36-138) encoding the entire variable region. SeM (CF32) specific mouse Mab 04D11 which reacted strongly with this larger peptide but not with shorter peptides within that sequence reacted strongly with whole cells of S. equi CF32 but only weakly with cells of any of 14 isolates of S. equi expressing different variants of SeM. These results in combination suggest that N-terminal variation alters a conformational epitope of significance in mucosal IgA and systemic T cell responses but does not affect antibody mediated phagocytosis and killing.

  11. An ORF2 protein-based ELISA for porcine circovirus type 2 antibodies in post-weaning multisystemic wasting syndrome.

    Science.gov (United States)

    Blanchard, Ph; Mahé, D; Cariolet, R; Truong, C; Le Dimna, M; Arnauld, C; Rose, N; Eveno, E; Albina, E; Madec, F; Jestin, A

    2003-07-17

    Porcine circovirus type 2 (PCV2) plays a crucial role in the pathogenesis of post-weaning multisystemic wasting syndrome (PMWS) in swine. As PCV2 displays significant homology with PCV1 (a non-pathogenic virus) at the nucleotide and amino-acid level, a discriminative antigen is needed for specific serological diagnosis. The ORF2-encoded capsid protein from PCV2 was used to develop an indirect enzyme-linked immunosorbent assay (ELISA). GST-fused capsid protein from PCV2 and GST alone (both expressed in recombinant baculovirus-infected cells) were used as antigens for serodiagnosis. The specificity of the ELISA for detection of PCV2 antibodies was demonstrated in sera from pigs experimentally infected with PCV1, PCV2 and other swine viruses. The semi-quantitative nature of the test was evaluated versus an immunoperoxidase monolayer assay (IPMA). The ELISA was performed on 322 sera from pigs in eight Brittany herds and compared with IPMA. The sensitivity (98.2%) and specificity (94.5%) of this test were considered suitable for individual serological detection. High PCV2 seroprevalence was found in sows and pigs at the end of the growth phase (18-19 weeks) in all eight herds. The seroprevalence in piglets (11-17 weeks) was statistically correlated with clinical symptoms of PMWS (93% in affected versus 54%, in non-affected farms). A cohort study performed in PMWS-free farms showed that 57% of piglets exhibited active seroconversion after 13 weeks, indicating that PCV2 infection occurred earlier in PMWS-affected piglets. PMID:12814886

  12. Humoral and Cell-mediated Autoimmune Reactions to Human Acidic Ribosomal P2 Protein in Individuals Sensitized to Aspergillus fumigatus P2 Protein

    Science.gov (United States)

    Mayer, Christina; Appenzeller, Ulrich; Seelbach, Heike; Achatz, Gernot; Oberkofler, Hannes; Breitenbach, Michael; Blaser, Kurt; Crameri, Reto

    1999-01-01

    A panel of cDNAs encoding allergenic proteins was isolated from an Aspergillus fumigatus cDNA library displayed on the surface of filamentous phage. Solid phase–immobilized serum immunoglobulin E (IgE) from A. fumigatus–allergic individuals was used to enrich phage displaying IgE-binding molecules. One of the cDNAs encoded a 11.1-kD protein that was identified as acidic ribosomal phosphoprotein type 2 (P2 protein). The allergen, formally termed rAsp f 8, shares >62% sequence identity and >84% sequence homology to corresponding eukaryotic P2 proteins, including human P2 protein. The sequences encoding human and fungal P2 protein were subcloned, expressed in Escherichia coli as His6-tagged fusion proteins, and purified by Ni2+–chelate affinity chromatography. Both recombinant P2 proteins were recognized by IgE antibodies from allergic individuals sensitized to the A. fumigatus P2 protein and elicited strong type 1–specific skin reactions in these individuals. Moreover, human and fungal P2 proteins induced proliferative responses in peripheral blood mononuclear cells of A. fumigatus– allergic subjects sensitized to the fungal P2 protein. These data provide strong evidence for in vitro and in vivo humoral and cell-mediated autoreactivity to human P2 protein in patients suffering from chronic A. fumigatus allergy. PMID:10224291

  13. Characterization of the antibody response against EV71 capsid proteins in Chinese individuals by NEIBM-ELISA.

    Science.gov (United States)

    Ding, Yingying; Chen, Xuguang; Qian, Baohua; Wu, Guorong; He, Ting; Feng, Jiaojiao; Gao, Caixia; Wang, Lili; Wang, Jinhong; Li, Xiangyu; Cao, Mingmei; Peng, Heng; Zhao, Chunyan; Pan, Wei

    2015-01-01

    Human enterovirus 71 (EV71) has become the major pathogen of hand, foot, and mouth disease (HFMD) worldwide, while the anti-EV71 antibody responses other than neutralizing epitopes have not been characterized. In this study, EV71 capsid proteins VP1, VP3, VP0 and various VP1 antigens were constructed to analyze anti-EV71 response in severe HFMD cases, non-HFMD outpatient children and normal adults using a novel evolved immunoglobulin-binding molecule (NEIBM)-based ELISA. The high prevalence of antibody responses against all three capsid proteins was demonstrated, and anti-EV71 VP1 showed the main antibody response. Anti-EV71 VP1 antibody response was found to predominantly target to epitopes based on the common enterovirus cross-reactive sequence. Moreover, inhibition pattern against anti-EV71 VP1 reactions in three groups was obviously different. Taken together, these results firstly characterized the anti-EV71 antibody responses which are predominantly against VP1 epitopes based on common enterovirus cross-reactive sequence. This finding could be helpful for the better understanding of anti-EV71 humoral immunity and useful for seroepidemiological surveillance.

  14. Immunization routes in cattle impact the levels and neutralizing capacity of antibodies induced against S. aureus immune evasion proteins.

    Science.gov (United States)

    Boerhout, Eveline; Vrieling, Manouk; Benedictus, Lindert; Daemen, Ineke; Ravesloot, Lars; Rutten, Victor; Nuijten, Piet; van Strijp, Jos; Koets, Ad; Eisenberg, Susanne

    2015-01-01

    Vaccines against S. aureus bovine mastitis are scarce and show limited protection only. All currently available vaccines are applied via the parenteral (usually intramuscular) route. It is unknown, however, whether this route is the most suitable to specifically increase intramammary immunity to combat S. aureus at the site of infection. Hence, in the present study, immunization via mucosal (intranasal; IN), intramuscular (triangle of the neck; IM), intramammary (IMM) and subcutaneous (suspensory ligament; SC) routes were analyzed for their effects on the quantity of the antibody responses in serum and milk as well as the neutralizing capacity of the antibodies within serum. The experimental vaccine comprised the recombinant S. aureus immune evasion proteins extracellular fibrinogen-binding protein (Efb) and the leukotoxin subunit LukM in an oil-in-water adjuvant combined with a hydrogel and alginate. The highest titer increases for both Efb and LukM specific IgG1 and IgG2 antibody levels in serum and milk were observed following SC/SC immunizations. Furthermore, the harmful effects of Efb and leukotoxin LukMF' on host-defense were neutralized by serum antibodies in a route-dependent manner. SC/SC immunization resulted in a significant increase in the neutralizing capacity of serum antibodies towards Efb and LukMF', shown by increased phagocytosis of S. aureus and increased viability of bovine leukocytes. Therefore, a SC immunization route should be considered when aiming to optimize humoral immunity against S. aureus mastitis in cattle. PMID:26411347

  15. Direct Channeling of Retinoic Acid between Cellular Retinoic Acid-Binding Protein II and Retinoic Acid Receptor Sensitizes Mammary Carcinoma Cells to Retinoic Acid-Induced Growth Arrest

    OpenAIRE

    Budhu, Anuradha S.; Noy, Noa

    2002-01-01

    Cellular retinoic acid-binding protein II (CRABP-II) is an intracellular lipid-binding protein that associates with retinoic acid with a subnanomolar affinity. We previously showed that CRABP-II enhances the transcriptional activity of the nuclear receptor with which it shares a common ligand, namely, the retinoic acid receptor (RAR), and we suggested that it may act by delivering retinoic acid to this receptor. Here, the mechanisms underlying the effects of CRABP-II on the transcriptional ac...

  16. Structural basis for the binding of the neutralizing antibody, 7D11, to the poxvirus L1 protein

    International Nuclear Information System (INIS)

    Medical countermeasures to prevent or treat smallpox are needed due to the potential use of poxviruses as biological weapons. Safety concerns with the currently available smallpox vaccine indicate a need for research on alternative poxvirus vaccine strategies. Molecular vaccines involving the use of proteins and/or genes and recombinant antibodies are among the strategies under current investigation. The poxvirus L1 protein, encoded by the L1R open reading frame, is the target of neutralizing antibodies and has been successfully used as a component of both protein subunit and DNA vaccines. L1-specific monoclonal antibodies (e.g., mouse monoclonal antibody mAb-7D11, mAb-10F5) with potent neutralizing activity bind L1 in a conformation-specific manner. This suggests that proper folding of the L1 protein used in molecular vaccines will affect the production of neutralizing antibodies and protection. Here, we co-crystallized the Fab fragment of mAb-7D11 with the L1 protein. The crystal structure of the complex between Fab-7D11 and L1 reveals the basis for the conformation-specific binding as recognition of a discontinuous epitope containing two loops that are held together by a disulfide bond. The structure of this important conformational epitope of L1 will contribute to the development of molecular poxvirus vaccines and also provides a novel target for anti-poxvirus drugs. In addition, the sequence and structure of Fab-7D11 will contribute to the development of L1-targeted immunotherapeutics

  17. Biodistribution and tumor imaging of an anti-CEA single-chain antibody-albumin fusion protein

    Energy Technology Data Exchange (ETDEWEB)

    Yazaki, Paul J. [Division of Cancer Immunotherapeutics and Tumor Immunology, Beckman Research Institute, City of Hope, Duarte, CA 91010 (United States)], E-mail: pyazaki@coh.org; Kassa, Thewodros; Cheung, Chia-wei; Crow, Desiree M. [Division of Cancer Immunotherapeutics and Tumor Immunology, Beckman Research Institute, City of Hope, Duarte, CA 91010 (United States); Sherman, Mark A. [Division of Information Sciences, Beckman Research Institute, City of Hope, Duarte, CA 91010 (United States); Bading, James R.; Anderson, Anne-Line J.; Colcher, David; Raubitschek, Andrew [Division of Cancer Immunotherapeutics and Tumor Immunology, Beckman Research Institute, City of Hope, Duarte, CA 91010 (United States)

    2008-02-15

    Albumin fusion proteins have demonstrated the ability to prolong the in vivo half-life of small therapeutic proteins/peptides in the circulation and thereby potentially increase their therapeutic efficacy. To evaluate if this format can be employed for antibody-based imaging, an anticarcinoembryonic antigen (CEA) single-chain antibody(scFv)-albumin fusion protein was designed, expressed and radiolabeled for biodistribution and imaging studies in athymic mice bearing human colorectal carcinoma LS-174T xenografts. The [{sup 125}I]-T84.66 fusion protein demonstrated rapid tumor uptake of 12.3% injected dose per gram (ID/g) at 4 h that reached a plateau of 22.7% ID/g by 18 h. This was a dramatic increase in tumor uptake compared to 4.9% ID/g for the scFv alone. The radiometal [{sup 111}In]-labeled version resulted in higher tumor uptake, 37.2% ID/g at 18 h, which persisted at the tumor site with tumor: blood ratios reaching 18:1 and with normal tissues showing limited uptake. Based on these favorable imaging properties, a pilot [{sup 64}Cu]-positron emission tomography imaging study was performed with promising results. The anti-CEA T84.66 scFv-albumin fusion protein demonstrates highly specific tumor uptake that is comparable to cognate recombinant antibody fragments. The radiometal-labeled version, which shows lower normal tissue accumulation than these recombinant antibodies, provides a promising and novel platform for antibody-based imaging agents.

  18. Blood stage merozoite surface protein conjugated to nanoparticles induce potent parasite inhibitory antibodies.

    Science.gov (United States)

    Pusic, Kae; Xu, Hengyi; Stridiron, Andrew; Aguilar, Zoraida; Wang, Andrew; Hui, George

    2011-11-01

    In this proof-of-concept study we report the use of nanoparticles as a vaccine delivery system for a blood stage malaria vaccine. The recombinant malarial antigen, Merozoite Surface Protein 1 (rMSP1) of Plasmodium falciparum served as the model vaccine. The rMSP1 was covalently conjugated to polymer-coated quantum dot CdSe/ZnS nanoparticles (QDs) via surface carboxyl groups, forming rMSP1-QDs. Anti-MSP1 antibody responses induced by rMSP1-QDs were found to have 2-3 log higher titers than those obtained with rMSP1 administered with the conventional adjuvants, Montanide ISA51 and CFA. Moreover, the immune responsiveness and the induction of parasite inhibitory antibodies were significantly superior in mice injected with rMSP1-QDs. The rMSP1-QDs delivered via intra-peritoneal (i.p.), intra-muscular (i.m.), and subcutaneous (s.c.) routes were equally efficacious. The high level of immunogenicity exhibited by the rMSP1-QDs was achieved without further addition of other adjuvant components. Bone marrow derived dendritic cells were shown to efficiently take up the nanoparticles leading to their activation and the expression/secretion of key cytokines, suggesting that this may be a mode of action for the enhanced immunogenicity. This study provides promising results for the use of water soluble, inorganic nanoparticles (<15 nm) as potent vehicles/platforms to enhance the immunogenicity of polypeptide antigens in adjuvant-free immunizations.

  19. Amino acid and glucose metabolism in fed-batch CHO cell culture affects antibody production and glycosylation

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Jimenez Del Val, Ioscani; Müller, Christian;

    2015-01-01

    and feeds were studied using two IgG-producing cell lines. Our results indicate that the balance of glucose and amino acid concentration in the culture is important for cell growth, IgG titer and N-glycosylation. Accordingly, the ideal fate of glucose and amino acids in the culture could be mainly towards......Fed-batch Chinese hamster ovary (CHO) cell culture is the most commonly used process for IgG production in the biopharmaceutical industry. Amino acid and glucose consumption, cell growth, metabolism, antibody titer, and N-glycosylation patterns are always the major concerns during upstream process....... Amino acids with the highest consumption rates correlate with the most abundant amino acids present in the produced IgG, and thus require sufficient availability during culture. Case-by-case analysis is necessary for understanding the effect of media and process optimization on glycosylation. We found...

  20. Fatty acid induced remodeling within the human liver fatty acid-binding protein.

    Science.gov (United States)

    Sharma, Ashwani; Sharma, Amit

    2011-09-01

    We crystallized human liver fatty acid-binding protein (LFABP) in apo, holo, and intermediate states of palmitic acid engagement. Structural snapshots of fatty acid recognition, entry, and docking within LFABP support a heads-in mechanism for ligand entry. Apo-LFABP undergoes structural remodeling, where the first palmitate ingress creates the atomic environment for placement of the second palmitate. These new mechanistic insights will facilitate development of pharmacological agents against LFABP. PMID:21757748

  1. Fatty Acid Induced Remodeling within the Human Liver Fatty Acid-binding Protein*

    OpenAIRE

    Sharma, Ashwani; Sharma, Amit

    2011-01-01

    We crystallized human liver fatty acid-binding protein (LFABP) in apo, holo, and intermediate states of palmitic acid engagement. Structural snapshots of fatty acid recognition, entry, and docking within LFABP support a heads-in mechanism for ligand entry. Apo-LFABP undergoes structural remodeling, where the first palmitate ingress creates the atomic environment for placement of the second palmitate. These new mechanistic insights will facilitate development of pharmacological agents against ...

  2. Effects of Protein Conformation, Apparent Solubility, and Protein-Protein Interactions on the Rates and Mechanisms of Aggregation for an IgG1Monoclonal Antibody.

    Science.gov (United States)

    Kalonia, Cavan; Toprani, Vishal; Toth, Ronald; Wahome, Newton; Gabel, Ian; Middaugh, C Russell; Volkin, David B

    2016-07-28

    Non-native protein aggregation is a key degradation pathway of immunoglobulins. In this work, the aggregation kinetics of an immunoglobulin gamma-1 monoclonal antibody (IgG1 mAb) in different solution environments was monitored over a range of incubation temperatures for up to seven months using size exclusion chromatography. Histidine and citrate buffers with/without sodium chloride were employed to modulate the mAb's conformational stability, solubility (in the presence of polyethylene glycol, PEG), and protein-protein interactions as measured by differential scanning calorimetry, PEG precipitation, and static light scattering, respectively. The effect of these parameters on the mechanism(s) of mAb aggregation during storage at different temperatures was determined using kinetic models, which were used to fit aggregation data to determine rate constants for aggregate nucleation and growth processes. This approach was used to investigate the effects of colloidal protein-protein interactions and solubility values (in PEG solutions) on the mechanisms and rates of IgG1 mAb aggregation as a function of temperature-induced structural perturbations. Aggregate nucleation and growth pathways for this IgG1 mAb were sensitive to temperature and overall conformational stability. Aggregate growth, on the other hand, was also sensitive to conditions affecting the solubility of the mAb, particularly at elevated temperatures. PMID:27380437

  3. Construction of single chain Fv antibody against transferrin receptor and its protein fusion with alkaline phosphatase

    Institute of Scientific and Technical Information of China (English)

    Dao-Feng Yang; Hui-Fen Zhu; Zhi-Hua Wang; Guan-Xin Shen; De-Ying Tian

    2005-01-01

    AIM: To construct fusion protein of a single-chain antibody(scFv) against transferrin receptor (TfR) with alkalinephosphatase (AP).METHODS: The VH-linker-VL, namely scFv gene, wasprepared by amplifying the VH and VL genes from plasmid pGEM-T-VH and pGEM-T-VL with splicing overlap extension polymerase chain reaction (SOE PCR). After the ScFv gene was modified by SfiⅠ and NotⅠ, it was subcloned into the secretory expression vector pUC19/119, and then was transformed into E. coli TG1. The positive colonies were screened by colony PCR and their expressions were induced by IPTG. ScFv gene was gained by digesting ScFv expression vector pUC19/119 with Sfi I and NotⅠ restriction enzymes, then subcloned into expression vector pDAP2, followed by transformation in E. coli TG1. The positive colonies were selected by bacterial colony PCR. The expression of fusion protein (scFv-AP) was induced by IPTG. Its activity was detected by enzyme immunoassay. The molecular weights of scFv and scFv-AP were measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE).RESULTS: The product of SOE PCR formed a band of 700 bp in agarose gel electrophoresis. SDS-PAGE demonstrated the molecular weight of scFv was 27 ku. Immunofluorescent assay (IFA) demonstrated its reactivity with TfR. The molecular weight of scFv-AP was 75 ku. Enzyme immunoassay showed that scFv-AP could specifically bind to human TfR and play AP activity.CONCLUSION: We have successfully prepared the antihuman TfR scFv and constructed the fusion protein of scFv and AP. It is promising for immunological experiments.

  4. Post-streptococcal auto-antibodies inhibit protein disulfide isomerase and are associated with insulin resistance.

    Directory of Open Access Journals (Sweden)

    Adi Aran

    Full Text Available Post-streptococcal autoimmunity affects millions worldwide, targeting multiple organs including the heart, brain, and kidneys. To explore the post-streptococcal autoimmunity spectrum, we used western blot analyses, to screen 310 sera from healthy subjects with (33% and without (67% markers of recent streptococcal infections [anti-Streptolysin O (ASLO or anti-DNAse B (ADB]. A 58 KDa protein, reacting strongly with post-streptococcal sera, was identified as Protein Disulfide Isomerase (PDI, an abundant protein with pleiotropic metabolic, immunologic, and thrombotic effects. Anti-PDI autoantibodies, purified from human sera, targeted similar epitopes in Streptolysin O (SLO, P51-61 and PDI (P328-338. The correlation between post-streptococcal status and anti-human PDI auto-immunity was further confirmed in a total of 2987 samples (13.6% in 530 ASLO positive versus 5.6% in 2457 ASLO negative samples, p<0.0001. Finally, anti-PDI auto-antibodies inhibited PDI-mediated insulin degradation in vitro (n = 90, p<0.001, and correlated with higher serum insulin (14.1 iu/ml vs. 12.2 iu/ml, n = 1215, p = 0.039 and insulin resistance (Homeostatic Model Assessment (HOMA 4.1 vs. 3.1, n = 1215, p = 0.004, in a population-based cohort. These results identify PDI as a major target of post-streptococcal autoimmunity, and establish a new link between infection, autoimmunity, and metabolic disturbances.

  5. Influenza A virus infection engenders a poor antibody response against the ectodomain of matrix protein 2

    Directory of Open Access Journals (Sweden)

    Wunner William

    2006-12-01

    Full Text Available Abstract Background Matrix protein 2 (M2 is an integral tetrameric membrane protein of influenza A virus (IAV. Its ectodomain (M2e shows remarkably little diversity amongst human IAV strains. As M2e-specific antibodies (Abs have been shown to reduce the severity of infection in animals, M2e is being studied for its capability of providing protection against a broad range of IAV strains. Presently, there is little information about the concentration of M2e-specific Abs in humans. Two previous studies made use of ELISA and Western blot against M2e peptides and recombinant M2 protein as immunosorbents, respectively, and reported Ab titers to be low or undetectable. An important caveat is that these assays may not have detected all Abs capable of binding to native tetrameric M2e. Therefore, we developed an assay likely to detect all M2e tetramer-specific Abs. Results We generated a HeLa cell line that expressed full length tetrameric M2 (HeLa-M2 or empty vector (HeLa-C10 under the control of the tetracycline response element. These cell lines were then used in parallel as immunosorbents in ELISA. The assay was standardized and M2e-specific Ab titers quantified by means of purified murine or chimeric (mouse variable regions, human constant regions M2e-specific Abs in the analysis of mouse and human sera, respectively. We found that the cell-based ELISA was substantially more effective than immobilized M2e peptide in detecting M2e-specific Abs in sera of mice that had recovered from repetitive IAV infections. Still, titers remained low ( Conclusion The results provide convincing evidence that M2e-specific Ab-mediated protection is currently lacking or suboptimal in humans.

  6. Mass spectral characterization of a protein-nucleic acid photocrosslink.

    OpenAIRE

    Golden, M. C.; Resing, K. A.; Collins, B. D.; Willis, M. C.; Koch, T H

    1999-01-01

    A photocrosslink between basic fibroblast growth factor (bFGF155) and a high affinity ssDNA oligonucleotide was characterized by positive ion electrospray ionization mass spectrometry (ESIMS). The DNA was a 61-mer oligonucleotide photoaptamer bearing seven bromodeoxyuridines, identified by in vitro selection. Specific photocrosslinking of the protein to the oligonucleotide was achieved by 308 nm XeCl excimer laser excitation. The cross-linked protein nucleic acid complex was proteolyzed with ...

  7. CB.Hep-1 hybridoma growth and antibody production using protein-free medium in a hollow fiber bioreactor

    OpenAIRE

    Valdés, R.; Ibarra, N.; González, M.; Alvarez, T.; GarcÍa, J.; Llambias, R.; Pérez, C. A.; Quintero, O.; Fischer, R

    2001-01-01

    The protein-free medium TurboDoma HP.1 (THP.1) was used to produce the CB.Hep-1 monoclonal antibody (mAb) in a CP-1000 hollow fiber bioreactor (HFB). This mAb is used for the immunopurification of recombinant hepatitis B surface antigen (rHBsAg), which is included in a vaccine preparation against the Hepatitis B Virus. By using the experimental conditions tested in this work we were able to generate more than 433 mg of IgG in 43 days. The maximum antibody concentration obtained was about 2.4 ...

  8. Effect of ochratoxin and aflatoxin on serum proteins, complement activity, and antibody production to Brucella abortus in guinea pigs.

    Science.gov (United States)

    Richard, J L; Thurston, J R; Deyoe, B L; Booth, G D

    1975-01-01

    The effect of ochratoxin alone and in combination with aflatoxin and Brucella abortus antigen on complement activity, serum proteins, and antibody response in guinea pigs was investigated. Ochratoxin did not affect complement activity or antibody response and there was no interaction between ochratoxin and aflatoxin on any of the responses tested. Ochratoxin significantly lowered the level of beta-globulin in serum of guinea pigs. There was no significant interaction between aflatoxin and antigen on lowering of the serum albumin levels of guinea pigs. PMID:45955

  9. Inhibition of Neisseria gonorrhoeae attachment to HeLa cells with monoclonal antibody directed against a protein II.

    OpenAIRE

    Sugasawara, R J; Cannon, J G; Black, W J; Nachamkin, I; Sweet, R L; Brooks, G F

    1983-01-01

    This study showed that a protein II (PII) of Neisseria gonorrhoeae FA1090 appeared to act as a mediator of attachment to HeLa cells. Two colony variants of FA1090 were selected. Both gonococcal variants were nonpiliated, but one contained a PII and the other did not. A monoclonal antibody (1090-10.1), which was directed against the PII, inhibited the apparent PII-mediated attachment to HeLa cells. Antibodies produced from clone 1035-4, which had no PII specificity, did not inhibit the attachm...

  10. Structural studies of nucleic acids and proteins involved in nucleic acid recognition

    OpenAIRE

    Russo Krauss, Irene

    2010-01-01

    This PhD thesis focuses on the structural analysis of the protein-nucleic acid recognition. In particular the research work has been focalized on two different kinds of proteins and their nucleotide ligands. The first part concerns the structural characterization of complexes between human α-thrombin, a protein of physiological and pathological relevance, and two oligonucleotide aptamers (the so called thrombin binding aptamer and a modified version of it), which adopt a G-quadruplex fold. Th...

  11. Isotype Diversification of IgG Antibodies to HIV Gag Proteins as a Therapeutic Vaccination Strategy for HIV Infection.

    Science.gov (United States)

    French, Martyn A; Abudulai, Laila N; Fernandez, Sonia

    2013-01-01

    The development of vaccines to treat and prevent human immunodeficiency virus (HIV) infection has been hampered by an incomplete understanding of "protective" immune responses against HIV. Natural control of HIV-1 infection is associated with T-cell responses against HIV-1 Gag proteins, particularly CD8⁺ T-cell responses restricted by "protective" HLA-B alleles, but other immune responses also contribute to immune control. These immune responses appear to include IgG antibodies to HIV-1 Gag proteins, interferon-a-dependant natural killer (NK) cell responses and plasmacytoid dendritic cell (pDC) responses. Here, it is proposed that isotype diversification of IgG antibodies against HIV-1 Gag proteins, to include IgG2, as well as IgG3 and IgG1 antibodies, will broaden the function of the antibody response and facilitate accessory cell responses against HIV-1 by NK cells and pDCs. We suggest that this should be investigated as a vaccination strategy for HIV-1 infection.

  12. Isotype Diversification of IgG Antibodies to HIV Gag Proteins as a Therapeutic Vaccination Strategy for HIV Infection

    Directory of Open Access Journals (Sweden)

    Sonia Fernandez

    2013-08-01

    Full Text Available The development of vaccines to treat and prevent human immunodeficiency virus (HIV infection has been hampered by an incomplete understanding of “protective” immune responses against HIV. Natural control of HIV-1 infection is associated with T-cell responses against HIV-1 Gag proteins, particularly CD8+ T-cell responses restricted by “protective” HLA-B alleles, but other immune responses also contribute to immune control. These immune responses appear to include IgG antibodies to HIV-1 Gag proteins, interferon-a-dependant natural killer (NK cell responses and plasmacytoid dendritic cell (pDC responses. Here, it is proposed that isotype diversification of IgG antibodies against HIV-1 Gag proteins, to include IgG2, as well as IgG3 and IgG1 antibodies, will broaden the function of the antibody response and facilitate accessory cell responses against HIV-1 by NK cells and pDCs. We suggest that this should be investigated as a vaccination strategy for HIV-1 infection.

  13. Production of soluble recombinant proteins with Kell, Duffy and Lutheran blood group antigen activity, and their use in screening human sera for Kell, Duffy and Lutheran antibodies.

    Science.gov (United States)

    Ridgwell, K; Dixey, J; Scott, M L

    2007-10-01

    The aim of this study was to show that soluble recombinant (sr) proteins can mimic blood group antigens and be used to screen human sera for blood-group-specific antibodies. The blood of all pregnant women and pretransfusion patients should be screened for blood-group-specific antibodies to identify and monitor pregnancies at risk of haemolytic disease of the foetus and newborn (HDFN), and to prevent haemolytic transfusion reactions. Current antibody screening and identification methods use human red blood cell panels, which can complicate antibody identification if more than one antibody specificity is present. COS-7 cells were transfected to produce sr forms of the extracellular domains of the red blood cell membrane proteins that express Kell, Duffy or Lutheran blood group antigens. These sr proteins were used to screen for and identify anti-Kell, anti-Duffy or anti-Lutheran blood-group-specific allo-antibodies in human sera by haemagglutination inhibition and in solid-phase enzyme-linked immunosorbent assays (ELISAs). There is a positive correlation (correlation coefficient 0.605, P value 0.002) between antibody titre by standard indirect antiglobulin test (IAT) and signal intensity in the ELISA test. This work shows that sr proteins can mimic blood group antigens and react with human allogeneic antibodies, and that such proteins could be used to develop solid-phase, high-throughput blood group antibody screening and identification platforms. PMID:17725551

  14. Development of a multiplexed bead-based immunoassay for the simultaneous detection of antibodies to 17 pneumococcal proteins.

    Science.gov (United States)

    Shoma, S; Verkaik, N J; de Vogel, C P; Hermans, P W M; van Selm, S; Mitchell, T J; van Roosmalen, M; Hossain, S; Rahman, M; Endtz, H Ph; van Wamel, W J B; van Belkum, A

    2011-04-01

    Presently, several pneumococcal proteins are being evaluated as potential vaccine candidates. Here, we gather novel insights in the immunogenicity of PLY, PsaA, PspA, PspC, NanA, Hyl, PpmA, SlrA, Eno, IgA1-protease, PdBD, BVH-3, SP1003, SP1633, SP1651, SP0189 and SP0376. We developed a multiplex bead-based immunoassay (xMAP(®) Technology, Luminex Corporation) to simultaneously quantify antibodies against these 17 pneumococcal proteins in serum. The median fluorescence intensity (MFI) values obtained for human pooled serum with the multiplex assay were between 82% and 111% (median 94%) of those obtained with the singleplex assays. For IgG, the coefficient of variation (CV) in serum ranged from 2% to 9%, for IgA, the CV ranged from 3% to 14% and for IgM, the CV ranged from 11% to 15%. Using this immunoassay, we showed that anti-pneumococcal antibody levels exhibited extensive inter-individual variability in young children suffering from invasive pneumococcal disease. All proteins, including the proteins with, as yet, unknown function, were immunogenic. In conclusion, the multiplex Streptococcus pneumoniae immunoassay based on proteins is reproducible. This assay can be used to monitor anti-S. pneumoniae antibody responses in a material- and time-saving manner. PMID:21086008

  15. Protein adsorption on ion exchange resins and monoclonal antibody charge variant modulation.

    Science.gov (United States)

    Guélat, Bertrand; Khalaf, Rushd; Lattuada, Marco; Costioli, Matteo; Morbidelli, Massimo

    2016-05-20

    A novel multicomponent adsorption equilibrium model for proteins on ion-exchange resins is developed on a statistical thermodynamic basis including surface coverage effects and protein-resin and protein-protein interactions. The resulting model exhibits a general competitive Langmuirian behavior and was applied to the study and optimization of the separation of monoclonal antibody charge variants on two strong cation exchangers. The model accounts explicitly for the effect of both pH and salt concentration, and its parameters can be determined in diluted conditions, that is, through physically sound assumptions, all model parameters can be obtained using solely experiments in diluted conditions, and be used to make predictions in overloaded conditions. The parameterization of the model and optimization of the separation is based on a two-step approach. First, gradient experiments in diluted conditions are undertaken in order to determine the model parameters. Based on these experiments and on information about the proteins of interest and the stationary phase used, all the model parameters can be estimated. Second, using the parameterized model, an initial Pareto optimization is undertaken where overloaded operating conditions are investigated. Experiments from this Pareto set are then used to refine the estimation of the model parameters. A second Pareto optimization can then be undertaken, this time with the refined parameters. This can be repeated until a satisfactory set of model parameters is found. This iterative approach is shown to be extremely efficient and to provide large amounts of knowledge based on only a few experiments. It is shown that due to the strong physical foundation of the model and the very low number of adjustable parameters, the number of iterations is expected to be at most two or three. Furthermore, the model based tool is improved as more experimental knowledge is provided, allowing for better estimations of the chromatographic

  16. Protein adsorption on ion exchange resins and monoclonal antibody charge variant modulation.

    Science.gov (United States)

    Guélat, Bertrand; Khalaf, Rushd; Lattuada, Marco; Costioli, Matteo; Morbidelli, Massimo

    2016-05-20

    A novel multicomponent adsorption equilibrium model for proteins on ion-exchange resins is developed on a statistical thermodynamic basis including surface coverage effects and protein-resin and protein-protein interactions. The resulting model exhibits a general competitive Langmuirian behavior and was applied to the study and optimization of the separation of monoclonal antibody charge variants on two strong cation exchangers. The model accounts explicitly for the effect of both pH and salt concentration, and its parameters can be determined in diluted conditions, that is, through physically sound assumptions, all model parameters can be obtained using solely experiments in diluted conditions, and be used to make predictions in overloaded conditions. The parameterization of the model and optimization of the separation is based on a two-step approach. First, gradient experiments in diluted conditions are undertaken in order to determine the model parameters. Based on these experiments and on information about the proteins of interest and the stationary phase used, all the model parameters can be estimated. Second, using the parameterized model, an initial Pareto optimization is undertaken where overloaded operating conditions are investigated. Experiments from this Pareto set are then used to refine the estimation of the model parameters. A second Pareto optimization can then be undertaken, this time with the refined parameters. This can be repeated until a satisfactory set of model parameters is found. This iterative approach is shown to be extremely efficient and to provide large amounts of knowledge based on only a few experiments. It is shown that due to the strong physical foundation of the model and the very low number of adjustable parameters, the number of iterations is expected to be at most two or three. Furthermore, the model based tool is improved as more experimental knowledge is provided, allowing for better estimations of the chromatographic

  17. The interaction of amino acids, peptides, and proteins with DNA.

    Science.gov (United States)

    Solovyev, Andrey Y; Tarnovskaya, Svetlana I; Chernova, Irina A; Shataeva, Larisa K; Skorik, Yury A

    2015-01-01

    Amino acids that carry charges on their side groups can bind to double stranded DNA (dsDNA) and change the strength of the double helix. Measurement of the DNA melting temperature (Tm) confirmed that acidic amino acids (Glu, Asp) weaken the H-bonds between DNA strands, whereas basic amino acids (Arg, Lys) strengthen the interaction between the strands. A rank correlation exists between the amino acid isoelectric points and the observed changes in Tm. A similar dependence of the hyperchromic effect on the isoelectric point of a protein (pepsin, insulin, cortexin, and protamine) was observed for DNA-protein complexes at room temperature. Short peptides (KE, AEDG, and KEDP) containing a mixture of acidic and basic amino acid residues also affect Tm and the stability of the double helix. A model for binding Glu and Lys to dsDNA was explored by a docking simulation. The model shows that Glu, in an untwisted shape, binds to dsDNA in its major groove and disrupts three H-bonds between the strands, thereby destabilizing the double helix. Lys, in an untwisted shape, binds to the external side of the dsDNA and forms two bonds with O atoms of neighboring phosphodiester groups, thereby strengthening the DNA helix.

  18. Inclusion of a non-immunoglobulin binding protein in two-site ELISA for quantification of human serum proteins without interference by heterophilic serum antibodies.

    Science.gov (United States)

    Andersson, Mårten; Rönnmark, Jenny; Areström, Iréne; Nygren, Per Ake; Ahlborg, Niklas

    2003-12-01

    Measurement of human serum molecules with two-site ELISA can be biased by the presence of human heterophilic anti-animal immunoglobulin antibodies (HAIA) that cause false-positive signals by cross-linking the monoclonal (mAb) and/or polyclonal antibodies (pAb) used for the pre- (capture) and post-analyte steps (detection). To evaluate a novel ELISA format designed to avoid interference by HAIA, a target-specific non-immunoglobulin (Ig) affinity protein (affibody) was used to replace one of the antibodies. First, a human IgA-binding affibody (Z(IgA)) selected by phage display technology from a combinatorial library of a single Staphylococcus aureus protein A domain was used. The detection range of IgA standard using an ELISA based on Z(IgA) for capture and goat pAb against IgA (pAb(IgA)) for detection was comparable with that of using pAb(IgA) for both capture and detection. Secondly, another affibody (Z(Apo)) was combined with mAb and used to detect recombinant human apolipoprotein A-1. The affibody/antibody ELISAs were also used to quantify human serum levels of IgA and apolipoprotein A1. To verify that human serum did not cause false-positive signals in the affibody/antibody ELISA format, the ability of human serum to cross-link affibodies, mAb (mouse or rat) and/or pAb (goat) displaying non-matched specificities was assessed; affibodies and antibodies were not cross-linked whereas all combinations of mAb and/or pAb were cross-linked. The combination of affibodies and antibodies for analysis of human serum molecules represents a novel two-site ELISA format which precludes false-positive signals caused by HAIA. PMID:14659914

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

    Directory of Open Access Journals (Sweden)

    Justas Lazutka

    2014-01-01

    Full Text Available Schmallenberg virus (SBV, discovered in continental Europe in late 2011, causes mild clinical signs in adult ruminants, including diarrhoea and reduced milk yield. However, fetal infection can lead to severe malformation in newborn offspring. To develop improved reagents for SBV serology, a high-level yeast expression system was employed to produce recombinant SBV nucleocapsid (N protein. Recombinant SBV N protein was investigated as an antigen in SBV-specific IgG enzyme immunoassay and used for generation of monoclonal antibodies (MAbs. Yeast-expressed SBV N protein was reactive with anti-SBV IgG-positive cow serum specimens collected from different farms of Lithuania. After immunization of mice with recombinant SBV N protein, four MAbs were generated. The MAbs raised against recombinant SBV N protein reacted with native viral nucleocapsids in SBV-infected BHK cells by immunofluorescence assay. The reactivity of recombinant N protein with SBV-positive cow serum specimens and the ability of the MAbs to recognize virus-infected cells confirm the antigenic similarity between yeast-expressed SBV N protein and native viral nucleocapsids. Our study demonstrates that yeast expression system is suitable for high-level production of recombinant SBV N protein and provides the first evidence on the presence of SBV-specific antibodies in cow serum specimens collected in Lithuania.

  20. Preparation and Characterization of Three Monoclonal Antibodies against HIV-1 p24 Capsid Protein

    Institute of Scientific and Technical Information of China (English)

    Guangjie Liu; Jianping Wang; Jianchun Xiao; Zhiwei Zhao; Yongtang Zheng

    2007-01-01

    HIV-1 p24 detection provides a means to aid the early diagnosis of HIV-1 infection, track the progression of disease and assess the efficacy of antiretroviral therapy. In the present study, three monoclonal antibodies (mAbs) p3JB9,p5F1 and p6F4 against HIV-1 p24 were generated. All mAbs could detect p24 of HIV-1ⅢB, HIV-1Ada-M, HIV-174v mAbs p5F1 and p6F4 could detect HIV-1KM018, while p3JB9 could not. Three mAbs did not react with HIV-2ROD,HIV-2CBL-20 and SIVagmTyo-1. The recognized epitope of p5F1 was located on the Gag amino acid region DCKTILKALGPAATLEEMMTAC. The p5F1 was used to establish a modified sandwich ELISA with rabbit anti-p24 serum and showed good specificity and high sensitivity, which has been used to measure HIV-1 p24 antigen levels in research.

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

    Directory of Open Access Journals (Sweden)

    Guowei Wei

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

  2. Hierarchical, domain type-specific acquisition of antibodies to Plasmodium falciparum erythrocyte membrane protein 1 in Tanzanian children

    DEFF Research Database (Denmark)

    Cham, Gerald K K; Turner, Louise; Kurtis, Jonathan D;

    2010-01-01

    Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is a variant antigen expressed on the surface of malaria-infected erythrocytes. PfEMP1 attaches to the vascular lining and allows infected erythrocytes to avoid filtration through the spleen. Each parasite genome encodes about 60...... different PfEMP1 variants, each PfEMP1 comprises several domains in its extracellular region, and the PfEMP1 repertoire in different parasites contains domain types that are serologically cross-reactive. In this longitudinal study, we followed 672 children living in an area of high malaria transmission...... in which individuals acquire antibodies to different PfEMP1 domains is ordered, and children in areas of endemicity first acquire antibodies to particular PfEMP1 domains encoded by the so-called group A and B/A var genes. The results imply that anti-PfEMP1 antibodies effectively structure PfEMP1 expression...

  3. Selection of complementary single-variable domains for building monoclonal antibodies to native proteins

    OpenAIRE

    Tanaka, Tomoyuki; Rabbitts, Terence H.

    2009-01-01

    Antibodies are now indispensable tools for all areas of cell biology and biotechnology as well as for diagnosis and therapy. Antigen-specific single immunoglobulin variable domains that bind to native antigens can be isolated and manipulated using yeast intracellular antibody capture technology but converting these to whole monoclonal antibody requires that complementary variable domains (VH or VL) bind to the same antigenic site. We describe a simple approach (CatcherAb) for specific isolati...

  4. Induction of DNA damage by oxidised amino acids and proteins

    DEFF Research Database (Denmark)

    Luxford, Catherine; Dean, Roger T; Davies, Michael Jonathan

    2002-01-01

    Exposure of amino acids, peptides and proteins to radicals in the presence of O2 generates hydroperoxides in a dose-dependent manner. These hydroperoxides are stable in the absence of exogenous catalysts (e.g. heat, light, redox-active transition metal ions), but decompose rapidly in the presence...

  5. Characterization of Niemann-Pick Type C2 protein expression in multiple cancers using a novel NPC2 monoclonal antibody.

    Directory of Open Access Journals (Sweden)

    Yi-Jen Liao

    Full Text Available Niemann-Pick Type C2 (NPC2 plays an important role in the regulation of intracellular cholesterol homeostasis via direct binding with free cholesterol. However, little is known about the significance of NPC2 in cancer. In this study, we have pinpointed the impact of various different cancers on NPC2 expression. A series of anti-NPC2 monoclonal antibodies (mAbs with the IgG2a isotype were generated and peptide screening demonstrated that the reactive epitope were amino acid residues 31-40 of the human NPC2 protein. The specificity of these mAbs was confirmed by Western blotting using shRNA mediated knock-down of NPC2 in human SK-Hep1 cells. By immunohistochemical staining, NPC2 is expressed in normal kidney, liver, breast, colon, lung, esophageal, uterine cervical, pancreatic and stomach tissue. Strong expression of NPC2 was found in the distal and proximal convoluted tubule of kidney and the hepatocytes of liver. Normal esophageal, uterine cervical, pancreatic, stomach, breast, colon and lung tissue stained moderately to weakly. When compared to their normal tissue equivalents, NPC2 overexpression was observed in cancers of the breast, colon and lung. Regarding to breast cancer, NPC2 up-regulation is associated with estrogen receptor (-, progesterone receptor (- and human epidermal growth factor receptor (+. On the other hand, NPC2 was found to be down-regulated in renal cell carcinoma, liver cirrhosis and hepatoma tissues. By antigen-capture enzyme immunoassay ELISA, the serum NPC2 is increased in patients with cirrhosis and liver cancer. According to western blot data, the change of glycosylated pattern of NPC2 in serum is associated with cirrhosis and liver cancer. To the best of our knowledge, this is the first comprehensive immunohistochemical and serological study investigating the expression of NPC2 in a variety of different human cancers. These novel monoclonal antibodies should help with elucidating the roles of NPC2 in tumor

  6. Application of GP5 protein to develop monoclonal antibody against porcine reproductive and respiratory syndrome virus.

    Science.gov (United States)

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

    2011-08-01

    In this study, a panel of monoclonal antibodies (mAbs) against Porcine reproductive and respiratory syndrome virus(PRRSV), named as 8C9 and4B4, were produced by fusing SP2/0 myeloma cells and spleen cells of BALB/c mice immunized with the PRRSV (TCID(50)=5.5), screened by the indirect ELISA and subjected to several limiting dilutions. mAbs were then identified by biological characterization. Among the two fusion cell strains, 8C9 belonged to the IgG1 subclass and 4B4 belonged to the IgG2a subclass. The titers in cell culture supernatant and abdomen liquor reached to 1:10(4)and 1:10(5), respectively. The specificity test indicated that the two cells had specific reactions for the PRRSV and GP5 protein respectively, and no reaction with Classical swine fever virus (CSFV) or Swine vesicular disease virus (SVDV). The molecular weights of the heavy chain and light chain were about 45.0 kDa and 25.0 kDa, respectively. In neutralization activity tests, the results showed that the prepared mAb 4B4 can protect 50% of cells with no CPE in dilution up to 1:512, but mAB 8C9 has no neutralization activities to PRRSV. PMID:21847758

  7. Quality Control System for Beer Developed with Monoclonal Antibodies Specific to Barley Lipid Transfer Protein

    Directory of Open Access Journals (Sweden)

    Yukie Murakami-Yamaguchi

    2012-10-01

    Full Text Available Non-specific lipid transfer protein (LTP in barley grain reacted with the IgE in sera drawn from food allergy patients. A sandwich-type of enzyme-linked immunosorbent assay (ELISA was developed with mouse monoclonal antibodies raised against LTP purified with barley flour. This ELISA showed a practical working range of 0.3–3 ng/mL and no cross-reactivity with wheat, adlay and rye. Using this ELISA, LTP was determined in several types of barley-foods, including fermented foods such as malt vinegar, barley-malt miso and beer. LTP content in beer of the same kind was approximately constant, even if manufacturing factory and production days were different. Not only as a factor of foam formation and stability but also as an allergen, controlling and monitoring of LTP in beer should be considered. Taken together, our LTP-detecting ELISA can be proposed as an appropriate system for the quality control of beer.

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

    Institute of Scientific and Technical Information of China (English)

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

    2011-01-01

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

  9. Recombinant outer membrane protein C of Aeromonas hydrophila elicits mixed immune response and generates agglutinating antibodies.

    Science.gov (United States)

    Yadav, Sunita Kumari; Meena, Jitendra Kumar; Sharma, Mahima; Dixit, Aparna

    2016-08-01

    Aeromonas hydrophila is a gram-negative fish pathogenic bacterium, also responsible for causing opportunistic pathological conditions in humans. It causes a number of diseases in fish due to which the fish industry incurs huge economic losses annually. Due to problems of antibiotic resistance, and the rapidity with which the infection spreads among fishes, vaccination remains the most effective strategy to combat this infection in fish populations. Among various virulence factors associated with bacterial virulence, outer membrane proteins have been widely evaluated for their vaccine potential owing to their surface exposure and related role in pathogenicity. In the present study, we have investigated the immunogenic potential of a non-specific porin, outer membrane protein C (OmpC) whose expression is regulated by the two-component regulatory system and plays a major role in the survival of A. hydrophila under different osmolaric conditions. The full-length gene (~1 kb) encoding OmpC of A. hydrophila was cloned, characterized and expressed in E. coli. High yield (~112 mg/L at shake flask level) of the recombinant OmpC (rOmpC) (~40 kDa) of A. hydrophila was obtained upon purification from inclusion bodies using Ni(2+)-NTA affinity chromatography. Immunization with purified rOmpC in murine model generated high endpoint (>1:40,000) titers. IgG isotyping, ELISA and ELISPOT assay indicated mixed immune response with a TH2 bias. Also, the anti-rOmpC antibodies were able to agglutinate A. hydrophila in vitro and exhibited specific cross-reactivity with different Aeromonas strains, which will facilitate easy detection of different Aeromonas isolates in infected samples. Taken together, these data clearly indicate that rOmpC could serve as an effective vaccine against different strains of Aeromonas, a highly heterogenous group of bacteria. PMID:27328672

  10. Human Antibodies that Recognize Novel Immunodominant Quaternary Epitopes on the HIV-1 Env Protein.

    Directory of Open Access Journals (Sweden)

    Mark D Hicar

    Full Text Available Numerous broadly neutralizing antibodies (Abs target epitopes that are formed or enhanced during mature HIV envelope formation (i.e. quaternary epitopes. Generally, it is thought that Env epitopes that induce broadly neutralizing Abs are difficult to access and poorly immunogenic because of the characteristic oligomerization, conformational flexibility, sequence diversity and extensive glycosylation of Env protein. To enhance for isolation of quaternary epitope-targeting Abs (QtAbs, we previously used HIV virus-like particles (VLPs to bind B cells from long-term non-progressor subjects to identify a panel of monoclonal Abs. When expressed as recombinant full-length Abs, a subset of these novel Abs exhibited the binding profiles of QtAbs, as they either failed to bind to monomeric Env protein or showed much higher affinity for Env trimers and VLPs. These QtAbs represented a significant proportion of the B-cell response identified with VLPs. The Ab genes of these clones were highly mutated, but they did not neutralize common HIV strains. We sought to further define the epitopes targeted by these QtAbs. Competition-binding and mapping studies revealed these Abs targeted four separate epitopes; they also failed to compete for binding by Abs to known major neutralizing epitopes. Detailed epitope mapping studies revealed that two of the four epitopes were located in the gp41 subunit of Env. These QtAbs bound pre-fusion forms of antigen and showed differential binding kinetics depending on whether oligomers were produced as recombinant gp140 trimers or as full-length Env incorporated into VLPs. Antigenic regions within gp41 present unexpectedly diverse structural epitopes, including these QtAb epitopes, which may be targeted by the naturally occurring Ab response to HIV infection.

  11. Human Antibodies that Recognize Novel Immunodominant Quaternary Epitopes on the HIV-1 Env Protein.

    Science.gov (United States)

    Hicar, Mark D; Chen, Xuemin; Sulli, Chidananda; Barnes, Trevor; Goodman, Jason; Sojar, Hakimuddin; Briney, Bryan; Willis, Jordan; Chukwuma, Valentine U; Kalams, Spyros A; Doranz, Benjamin J; Spearman, Paul; Crowe, James E

    2016-01-01

    Numerous broadly neutralizing antibodies (Abs) target epitopes that are formed or enhanced during mature HIV envelope formation (i.e. quaternary epitopes). Generally, it is thought that Env epitopes that induce broadly neutralizing Abs are difficult to access and poorly immunogenic because of the characteristic oligomerization, conformational flexibility, sequence diversity and extensive glycosylation of Env protein. To enhance for isolation of quaternary epitope-targeting Abs (QtAbs), we previously used HIV virus-like particles (VLPs) to bind B cells from long-term non-progressor subjects to identify a panel of monoclonal Abs. When expressed as recombinant full-length Abs, a subset of these novel Abs exhibited the binding profiles of QtAbs, as they either failed to bind to monomeric Env protein or showed much higher affinity for Env trimers and VLPs. These QtAbs represented a significant proportion of the B-cell response identified with VLPs. The Ab genes of these clones were highly mutated, but they did not neutralize common HIV strains. We sought to further define the epitopes targeted by these QtAbs. Competition-binding and mapping studies revealed these Abs targeted four separate epitopes; they also failed to compete for binding by Abs to known major neutralizing epitopes. Detailed epitope mapping studies revealed that two of the four epitopes were located in the gp41 subunit of Env. These QtAbs bound pre-fusion forms of antigen and showed differential binding kinetics depending on whether oligomers were produced as recombinant gp140 trimers or as full-length Env incorporated into VLPs. Antigenic regions within gp41 present unexpectedly diverse structural epitopes, including these QtAb epitopes, which may be targeted by the naturally occurring Ab response to HIV infection. PMID:27411063

  12. 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.

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

    Science.gov (United States)

    Beaumont, Elodie; Roch, Emmanuelle; Chopin, Lucie; Roingeard, Philippe

    2016-01-01

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

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

    Science.gov (United States)

    Beaumont, Elodie; Roch, Emmanuelle; Chopin, Lucie; Roingeard, Philippe

    2016-01-01

    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. PMID:26966906

  15. Maternal Antibodies to Pneumolysin but Not to Pneumococcal Surface Protein A Delay Early Pneumococcal Carriage in High-Risk Papua New Guinean Infants▿

    OpenAIRE

    Francis, Jacinta P.; Peter C Richmond; Pomat, William S.; Michael, Audrey; Keno, Helen; Phuanukoonnon, Suparat; Nelson, Jan B.; Whinnen, Melissa; Heinrich, Tatjana; Smith, Wendy-Anne; Prescott, Susan L.; Holt, Patrick G; Siba, Peter M.; Lehmann, Deborah; Anita H J van den Biggelaar

    2009-01-01

    Immunization of pregnant women can be an efficient strategy to induce early protection in infants in developing countries. Pneumococcal protein-based vaccines may have the capacity to induce pneumococcal serotype-independent protection. To understand the potential of maternal pneumococcal protein-specific antibodies in infants in high-risk areas, we studied the placental transfer of naturally acquired antibodies to pneumolysin (Ply) and pneumococcal surface protein A family 1 and 2 (PspA1 and...

  16. Feasibility study of semi-selective protein precipitation with salt-tolerant copolymers for industrial purification of therapeutic antibodies.

    Science.gov (United States)

    Capito, Florian; Bauer, Johann; Rapp, Almut; Schröter, Christian; Kolmar, Harald; Stanislawski, Bernd

    2013-11-01

    We present a feasibility study for an antibody capturing process from clarified cell culture fluid using semi-selective protein precipitation with salt-tolerant copolymers. Protein precipitation is mediated by hydrophobic and electrostatic interactions with the copolymer that can be customized for the respective target. Precipitation yield with different copolymers at ionic strength of 2-22.5 mS cm⁻¹ and pH 5.0-pH 5.7 was evaluated using pure monoclonal antibody solutions. Optimized parameters were used to elucidate yield and purity of various antibodies precipitated at physiological conditions from cell culture fluid of CHO, NS0, and SP2/0 cell culture fluid. Precipitated protein was easily redissolved in small volume, enabling concentrating monoclonal antibodies (mAb) more than 40-fold and up to 100-fold, while residual polymer was removed to >98% using cationic polymer attached to silica flakes. mAb recovery of >90% and host cell protein clearance of >80% were achieved, not requiring any pre-dilution of cell culture fluid. Precipitation showed no impact on mAb binding affinity when compared to non-precipitated mAb. The obtained yield and purity were lower compared to a protein A based purification and loss of mAb was factor 1.5-3.0 higher. Yet, for high titer mAb purification processes being implemented in the future, precipitation is an attractive option due to its ease of scalability and cost-effectiveness. PMID:23637026

  17. Insulin Receptor Antibody-α-N-Acetylglucosaminidase Fusion Protein Penetrates the Primate Blood-Brain Barrier and Reduces Glycosoaminoglycans in Sanfilippo Type B Fibroblasts.

    Science.gov (United States)

    Boado, Ruben J; Lu, Jeff Zhiqiang; Hui, Eric Ka-Wai; Lin, Huilan; Pardridge, William M

    2016-04-01

    Mucopolysaccharidosis Type IIIB (MPSIIIB) is caused by mutations in the gene encoding the lysosomal enzyme, α-N-acetylglucosaminidase (NAGLU). MPSIIIB presents with severe disease of the central nervous system, but intravenous NAGLU enzyme replacement therapy has not been developed because the NAGLU enzyme does not cross the blood-brain barrier (BBB). A BBB-penetrating form of the enzyme was produced by re-engineering NAGLU as an IgG-enzyme fusion protein, where the IgG domain is a monoclonal antibody (mAb) against the human insulin receptor (HIR). The HIRMAb traverses the BBB via transport on the endogenous insulin receptor and acts as a molecular Trojan horse to ferry the fused NAGLU across the BBB from blood. The NAGLU was fused to the carboxyl terminus of each heavy chain of the HIRMAb via an extended 31-amino acid linker, and the fusion protein is designated HIRMAb-LL-NAGLU. The fusion protein retains high affinity binding to the HIR, and on a molar basis has an enzyme activity equal to that of recombinant human NAGLU. Treatment of MPSIIIB fibroblasts with the fusion protein normalizes intracellular NAGLU enzyme activity and reduces sulfate incorporation into intracellular glycosoaminoglycan. The fusion protein is targeted to the lysosomal compartment of the cells as shown by confocal microscopy. The fusion protein was radiolabeled with the [(125)I]-Bolton-Hunter reagent and injected intravenously in the adult Rhesus monkey. The fusion protein was rapidly cleared from plasma by all major peripheral organs. The high brain uptake of the fusion protein, 1% injected dose/brain, enables normalization of brain NAGLU enzyme activity with a therapeutic dose of 1 mg/kg. The HIRMAb-LL-NAGLU fusion protein is a new treatment of the brain in MPSIIIB, which can be administered by noninvasive intravenous infusion. PMID:26910785

  18. Cloning and expression of a truncated pigeon circovirus capsid protein suitable for antibody detection in infected pigeons.

    Science.gov (United States)

    Daum, Iris; Finsterbusch, Tim; Härtle, Stefan; Göbel, Thomas W; Mankertz, Annette; Korbel, Rüdiger; Grund, Christian

    2009-04-01

    Infections with pigeon circovirus (PiCV) (also termed columbid circovirus) occur in meat and racing pigeons (Columba livia) of all ages and have been reported worldwide. A PiCV infection is associated with immunosuppression and the development of young pigeon disease syndrome. An indirect enzyme-linked immunosorbent assay (ELISA) for the detection of virus-specific serum antibody was developed for research purposes. In the absence of a method to propagate PiCV in cell culture, the assay was based on a recombinant truncated capsid protein (rCapPiCV) produced by overexpression in Escherichia coli. A 6xHis-Tag was fused to the N-terminus of the protein to facilitate purification by metal affinity chromatography and detection by anti-His antibody. PiCV-negative and PiCV-positive control sera were generated by inoculation of pigeons with tissue homogenate containing PiCV, followed by five weekly blood sample collections. Western blotting of the immune serum revealed a specific protein band of approximately 32 kDa, which was absent in the pre-immune sera. Using rCapPiCV as antigen in an indirect ELISA, PiCV-specific antibody was detected in sera of the experimentally PiCV-infected pigeons collected at 1 to 5 weeks post infection. By testing 118 field sera collected in the years 1989, 1991, 1994 and 2008 in the rCapPiCV ELISA, virus-specific antibody was detected in 89 (75%) of the sera. The results obtained demonstrate that the rCapPiCV-based indirect ELISA is able to detect PiCV-specific antibodies in pigeon sera and may be a useful tool for PiCV serodiagnosis.

  19. Antibody-targeted horseradish peroxidase associated with indole-3-acetic acid induces apoptosis in vitro in hematological malignancies.

    Science.gov (United States)

    Dalmazzo, Leandro F F; Santana-Lemos, Bárbara A; Jácomo, Rafael H; Garcia, Aglair B; Rego, Eduardo M; da Fonseca, Luiz M; Falcão, Roberto P

    2011-05-01

    Indole-3-acetic acid (IAA), when oxidized by horseradish peroxidase (HRP), is transformed into cytotoxic molecules capable of inducing cell injury. The aim of this study was to test if, by targeting hematopoietic tumors with HRP-conjugated antibodies in association with IAA treatment, there is induction of apoptosis. We used two lineages of hematologic tumors: NB4, derived from acute promyelocytic leukemia (APL) and Granta-519 from mantle cell lymphoma (MCL). We also tested cells from 12 patients with acute myeloid leukemia (AML) and from 10 patients with chronic lymphocytic leukemia (CLL). HRP targeting was performed with anti-CD33 or anti-CD19 antibodies (depending on the origin of the cell), followed by incubation with goat anti-mouse antibody conjugated with HRP. Eight experimental groups were analyzed: control, HRP targeted, HRP targeted and incubated with 1, 5 and 10mM IAA, and cells not HRP targeted but incubated with 1, 5 and 10mM IAA. Apoptosis was analyzed by flow cytometry using annexin V-FITC and propidium iodide labeling. Results showed that apoptosis was dependent on the dose of IAA utilized, the duration of exposure to the prodrug and the origin of the neoplasia. Targeting HRP with antibodies was efficient in activating IAA and inducing apoptosis. PMID:21168913

  20. A Novel Monoclonal Antibody Against a Synthetic Peptide from β-Actin can React with its Corresponding Protein.

    Science.gov (United States)

    Amini, Nazila; Bayat, Ali-Ahmad; Zarei, Omid; Hadavi, Reza; Mahmoudian, Jafar; Mahmoudi, Ahmad R; Darzi, Maryam; Rabbani, Hodjattallah; Jeddi-Tehrani, Mahmood

    2015-01-01

    Actin is one of the most widely studied structural and multifunctional housekeeping proteins in eukaryotic cells with important roles in many cell functions. Antibodies against β-actin and other housekeeping gene-encoded proteins are used as internal loading controls in Western blot analyses. The aim of this study was to produce a monoclonal antibody (mAb) against a synthetic peptide derived from N-terminal region of β-actin and to study its reactivity with different organisms. A synthetic peptide, derived from β-actin, was designed and used to produce a mAb by hybridoma technology. The produced antibody (clone 4E5- A10) was purified by an affinity chromatography column followed by characterization of purified mAb using SDS-PAGE, ELISA and Western blot. Our results showed that 4E5-A10 was an IgM and had desired purity and excellent reactivity with the immunizing peptide with an affinity constant of 2.7x10(8) M(-1)>. It could detect a band of about 45 kDa, corresponding to β-actin, in Western blot. Furthermore, it could react in a more sensitive manner and with a wider range of organisms than a known commercial anti β-actin antibody. Our data suggest that 4E5-A10 can act as a sensitive probe for detection of β-actin as an internal loading control, for a wide range of organisms, in Western blot analyses. PMID:25552314

  1. Sequence and structural features of binding site residues in protein-protein complexes: comparison with protein-nucleic acid complexes

    Directory of Open Access Journals (Sweden)

    Selvaraj S

    2011-10-01

    Full Text Available Abstract Background Protein-protein interactions are important for several cellular processes. Understanding the mechanism of protein-protein recognition and predicting the binding sites in protein-protein complexes are long standing goals in molecular and computational biology. Methods We have developed an energy based approach for identifying the binding site residues in protein–protein complexes. The binding site residues have been analyzed with sequence and structure based parameters such as binding propensity, neighboring residues in the vicinity of binding sites, conservation score and conformational switching. Results We observed that the binding propensities of amino acid residues are specific for protein-protein complexes. Further, typical dipeptides and tripeptides showed high preference for binding, which is unique to protein-protein complexes. Most of the binding site residues are highly conserved among homologous sequences. Our analysis showed that 7% of residues changed their conformations upon protein-protein complex formation and it is 9.2% and 6.6% in the binding and non-binding sites, respectively. Specifically, the residues Glu, Lys, Leu and Ser changed their conformation from coil to helix/strand and from helix to coil/strand. Leu, Ser, Thr and Val prefer to change their conformation from strand to coil/helix. Conclusions The results obtained in this study will be helpful for understanding and predicting the binding sites in protein-protein complexes.

  2. Further evaluation of an ELISA kit for detection of antibodies to a nonstructural protein of foot-and-mouth disease virus.

    Science.gov (United States)

    Fukai, Katsuhiko; Nishi, Tatsuya; Morioka, Kazuki; Yamada, Manabu; Yoshida, Kazuo; Kitano, Rie; Yamazoe, Reiko; Kanno, Toru

    2016-04-01

    An ELISA kit for detection of antibodies to a nonstructural protein of foot-and-mouth disease (FMDV) was further evaluated using sequentially collected serum samples of experimentally infected animals, because the sensitivity of the kit used in a previous study was significantly low in field animals. The kit fully detected antibodies in infected animals without vaccination; however, the first detections of antibodies by the kit were later than those by the liquid-phase blocking ELISA that is used for serological surveillance in the aftermath of outbreaks in Japan, for detection of antibodies to structural proteins of FMDV. Additionally, although the kit effectively detected antibodies in infected cattle with vaccination, there were several infected pigs with vaccination for which the kit did not detect antibodies during the experimental period. Taken together, the kit may not be suitable for serological surveillance after an FMD outbreak either with or without emergency vaccination in FMD-free countries. PMID:26498533

  3. Polyclonal and monoclonal antibodies specific for the six-helix bundle of the human respiratory syncytial virus fusion glycoprotein as probes of the protein post-fusion conformation

    Energy Technology Data Exchange (ETDEWEB)

    Palomo, Concepción; Mas, Vicente; Vázquez, Mónica; Cano, Olga [Unidad de Biología Viral, Centro Nacional de Microbiología, Madrid (Spain); CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid (Spain); Luque, Daniel; Terrón, María C. [Unidad de Microscopía Electrónica y Confocal, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid (Spain); Calder, Lesley J. [National Institute for Medical Research, MRC, Mill Hill, London NW7 1AA (United Kingdom); Melero, José A., E-mail: jmelero@isciii.es [Unidad de Biología Viral, Centro Nacional de Microbiología, Madrid (Spain); CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid (Spain)

    2014-07-15

    Human respiratory syncytial virus (hRSV) has two major surface glycoproteins (G and F) anchored in the lipid envelope. Membrane fusion promoted by hRSV{sub F} occurs via refolding from a pre-fusion form to a highly stable post-fusion state involving large conformational changes of the F trimer. One of these changes results in assembly of two heptad repeat sequences (HRA and HRB) into a six-helix bundle (6HB) motif. To assist in distinguishing pre- and post-fusion conformations of hRSV{sub F}, we have prepared polyclonal (α-6HB) and monoclonal (R145) rabbit antibodies specific for the 6HB. Among other applications, these antibodies were used to explore the requirements of 6HB formation by isolated protein segments or peptides and by truncated mutants of the F protein. Site-directed mutagenesis and electron microscopy located the R145 epitope in the post-fusion hRSV{sub F} at a site distantly located from previously mapped epitopes, extending the repertoire of antibodies that can decorate the F molecule. - Highlights: • Antibodies specific for post-fusion respiratory syncytial virus fusion protein are described. • Polyclonal antibodies were obtained in rabbit inoculated with chimeric heptad repeats. • Antibody binding required assembly of a six-helix bundle in the post-fusion protein. • A monoclonal antibody with similar structural requirements is also described. • Binding of this antibody to the post-fusion protein was visualized by electron microscopy.

  4. A conserved patch of hydrophobic amino acids modulates Myb activity by mediating protein-protein interactions.

    Science.gov (United States)

    Dukare, Sandeep; Klempnauer, Karl-Heinz

    2016-07-01

    The transcription factor c-Myb plays a key role in the control of proliferation and differentiation in hematopoietic progenitor cells and has been implicated in the development of leukemia and certain non-hematopoietic tumors. c-Myb activity is highly dependent on the interaction with the coactivator p300 which is mediated by the transactivation domain of c-Myb and the KIX domain of p300. We have previously observed that conservative valine-to-isoleucine amino acid substitutions in a conserved stretch of hydrophobic amino acids have a profound effect on Myb activity. Here, we have explored the function of the hydrophobic region as a mediator of protein-protein interactions. We show that the hydrophobic region facilitates Myb self-interaction and binding of the histone acetyl transferase Tip60, a previously identified Myb interacting protein. We show that these interactions are affected by the valine-to-isoleucine amino acid substitutions and suppress Myb activity by interfering with the interaction of Myb and the KIX domain of p300. Taken together, our work identifies the hydrophobic region in the Myb transactivation domain as a binding site for homo- and heteromeric protein interactions and leads to a picture of the c-Myb transactivation domain as a composite protein binding region that facilitates interdependent protein-protein interactions of Myb with regulatory proteins. PMID:27080133

  5. A conserved patch of hydrophobic amino acids modulates Myb activity by mediating protein-protein interactions.

    Science.gov (United States)

    Dukare, Sandeep; Klempnauer, Karl-Heinz

    2016-07-01

    The transcription factor c-Myb plays a key role in the control of proliferation and differentiation in hematopoietic progenitor cells and has been implicated in the development of leukemia and certain non-hematopoietic tumors. c-Myb activity is highly dependent on the interaction with the coactivator p300 which is mediated by the transactivation domain of c-Myb and the KIX domain of p300. We have previously observed that conservative valine-to-isoleucine amino acid substitutions in a conserved stretch of hydrophobic amino acids have a profound effect on Myb activity. Here, we have explored the function of the hydrophobic region as a mediator of protein-protein interactions. We show that the hydrophobic region facilitates Myb self-interaction and binding of the histone acetyl transferase Tip60, a previously identified Myb interacting protein. We show that these interactions are affected by the valine-to-isoleucine amino acid substitutions and suppress Myb activity by interfering with the interaction of Myb and the KIX domain of p300. Taken together, our work identifies the hydrophobic region in the Myb transactivation domain as a binding site for homo- and heteromeric protein interactions and leads to a picture of the c-Myb transactivation domain as a composite protein binding region that facilitates interdependent protein-protein interactions of Myb with regulatory proteins.

  6. Immunoglobulin M and G antibody responses to Plasmodium falciparum glutamate-rich protein

    DEFF Research Database (Denmark)

    Dziegiel, M; Rowe, P; Bennett, S;

    1993-01-01

    -GLURP489-1271 antibodies and clinical immunity is not clear; asymptomatically infected children aged 5 to 8 years had significantly higher levels of IgG than clinically ill children of the same age, suggesting that antibodies to the carboxy-terminal part of the GLURP may contribute to immunity to P....... falciparum. However, this was not significant for younger children....

  7. Prokaryotic Expression, Purification, Antibody Production of a NH2-Terminal Fragment of mCLCA3 Protein and Analysis of mClCA3 Protein Expression in Asthmatic Mouse Lung

    Institute of Scientific and Technical Information of China (English)

    HOU Xia; WU Qing-tian; ZHANG Yu-ping; ZHU Na; LIU Yan-li; FENG Xue-chao; MA Tong-hui

    2007-01-01

    mCLCA3 is a member of calcium activated chloride channel(CACC) family that may play an important role in mucin packaging and secretion in asthmatic and cystic fibrosis lung. To study the protein structure and expression of mCLCA3 in asthmatic mouse lung, an N-terminal 269 amino acid peptide of mCLCA3 was expressed in E. coli, purified to homogeneity and rabbit polyclonal antibodies against this peptide were generated. Immunohistochemistry of asthmatic mouse lung using the antibody indicated exclusive mCLCA3 expression in mucin granules of goblet cells in airway surface and lumen. Immunoblot analysis of lavage fluid from asthmatic mouse lung revealed a single 90 kDa protein form of mClCA3. The results demonstrate that the 90 kDa N-terminal peptide, neither the full-length protein nor the reported N-terminal 35 kDa cleaved form of mClCA3 is the major functional form involved in the packaging and exocytosis of mucin granules in asthmatic goblet cells.

  8. Nucleic Acid, Antibody, and Virus Culture Methods to Detect Xenotropic MLV-Related Virus in Human Blood Samples

    Directory of Open Access Journals (Sweden)

    M. F. Kearney

    2011-01-01

    Full Text Available The MLV-related retrovirus, XMRV, was recently identified and reported to be associated with both prostate cancer and chronic fatigue syndrome. At the National Cancer Institute-Frederick, MD (NCI-Frederick, we developed highly sensitive methods to detect XMRV nucleic acids, antibodies, and replication competent virus. Analysis of XMRV-spiked samples and/or specimens from two pigtail macaques experimentally inoculated with 22Rv1 cell-derived XMRV confirmed the ability of the assays used to detect XMRV RNA and DNA, and culture isolatable virus when present, along with XMRV reactive antibody responses. Using these assays, we did not detect evidence of XMRV in blood samples ( or prostate specimens ( from two independent cohorts of patients with prostate cancer. Previous studies detected XMRV in prostate tissues. In the present study, we primarily investigated the levels of XMRV in blood plasma samples collected from patients with prostate cancer. These results demonstrate that while XMRV-related assays developed at the NCI-Frederick can readily measure XMRV nucleic acids, antibodies, and replication competent virus, no evidence of XMRV was found in the blood of patients with prostate cancer.

  9. Detection and purification of rat and goat immunoglobulin G antibodies using protein G-based solid phase radioimmunoassays

    International Nuclear Information System (INIS)

    Using the newly described streptococcal surface protein, protein G, which has powerful immunoglobulin G binding properties, solid-phase radioimmunoassays were developed for the quantitation of goat and rat immunoglobulin G bound to the plastic surface of microtiter plates. The binding of goat immunoglobulin G to the surface via a specific antigen (guinea pig alpha1-microglobulin) permitted the determination of antigen-specific antibodies with a detection limit of 50-100 ng. Optimum assay conditions were established and the whole assay procedure could be brought to completion at room temperature in less than a working day. The value of the assays was illustrated by monitoring rat and goat immunoglobulin G antibodies during their purification from whole sera by classical chromatographic procedures. (Auth.)

  10. In silico classification of proteins from acidic and neutral cytoplasms.

    Directory of Open Access Journals (Sweden)

    Yaping Fang

    Full Text Available Protein acidostability is a common problem in biopharmaceutical and other industries. However, it remains a great challenge to engineer proteins for enhanced acidostability because our knowledge of protein acidostabilization is still very limited. In this paper, we present a comparative study of proteins from bacteria with acidic (AP and neutral cytoplasms (NP using an integrated statistical and machine learning approach. We construct a set of 393 non-redundant AP-NP ortholog pairs and calculate a total of 889 sequence based features for these proteins. The pairwise alignments of these ortholog pairs are used to build a residue substitution propensity matrix between APs and NPs. We use Gini importance provided by the Random Forest algorithm to rank the relative importance of these features. A scoring function using the 10 most significant features is developed and optimized using a hill climbing algorithm. The accuracy of the score function is 86.01% in predicting AP-NP ortholog pairs and is 76.65% in predicting non-ortholog AP-NP pairs, suggesting that there are significant differences between APs and NPs which can be used to predict relative acidostability of proteins. The overall trends uncovered in the study can be used as general guidelines for designing acidostable proteins. To best of our knowledge, this work represents the first systematic comparative study of the acidostable proteins and their non-acidostable orthologs.

  11. Cholesterol-lowering effect of rice bran protein containing bile acid-binding proteins.

    Science.gov (United States)

    Wang, Jilite; Shimada, Masaya; Kato, Yukina; Kusada, Mio; Nagaoka, Satoshi

    2015-01-01

    Dietary plant protein is well known to reduce serum cholesterol levels. Rice bran is a by-product of rice milling and is a good source of protein. The present study examined whether feeding rats a high-cholesterol diet containing 10% rice bran protein (RBP) for 10 d affected cholesterol metabolism. Rats fed dietary RBP had lower serum total cholesterol levels and increased excretion of fecal steroids, such as cholesterol and bile acids, than those fed dietary casein. In vitro assays showed that RBP strongly bound to taurocholate, and inhibited the micellar solubility of cholesterol, compared with casein. Moreover, the bile acid-binding proteins of the RBP were eluted by a chromatographic column conjugated with cholic acid, and one of them was identified as hypothetical protein OsJ_13801 (NCBI accession No. EAZ29742) using MALDI-TOF mass spectrometry analysis. These results suggest that the hypocholesterolemic action of the RBP may be caused by the bile acid-binding proteins. PMID:25374002

  12. Reduction in the level of antibodies against heat shock proteins 60 during different hormonal protocols in postmenopausal women

    OpenAIRE

    Rajtar-Ciosek, Agnieszka; Kacalska-Janssen, Olga; Zmaczyński, Andrzej; Wyroba, Jakub; Tomczyk, Rita; Wiatr, Joanna; Gałuszka-Bednarczyk, Anna; Bereza, Tomasz; Milewicz, Tomasz; Krzysiek, Józef

    2015-01-01

    Introduction In current literature, the immune-inflammatory theory of atherosclerosis is widely discussed. The role of how heat shock proteins 60 (HSP60) lead to the development of the atheromatous plaque is especially underlined. The aim of the study is to estimate the influence of three hormonal protocols on behavior of antibodies against HSP60. It determines the state of endothelium in postmenopausal women. Material and methods The study was carried out on 90 women between 2007 and 2012. A...

  13. γ-Synuclein Antibodies Have Neuroprotective Potential on Neuroretinal Cells via Proteins of the Mitochondrial Apoptosis Pathway

    OpenAIRE

    Corina Wilding; Katharina Bell; Sabine Beck; Sebastian Funke; Norbert Pfeiffer; Grus, Franz H.

    2014-01-01

    The family of synuclein proteins (α, β and γ) are related to neurodegenerative disease e.g. Parkinson disease and Morbus Alzheimer. Additionally, a connection between γ-synuclein and glaucoma, a neurodegenerative disease characterized by a progressive loss of retinal ganglion cells, which finally leads to blindness, exists. The reason for the development of glaucoma is still unknown. Recent studies evaluating the participation of immunological components, demonstrate complex changed antibody ...

  14. Higher levels of mucosal antibody to pneumococcal vaccine candidate proteins are associated with reduced acute otitis media caused by Streptococcus pneumoniae in young children.

    Science.gov (United States)

    Xu, Q; Casey, J R; Pichichero, M E

    2015-09-01

    Mucosal immunity has a crucial role in controlling human respiratory tract infections. This study characterizes the naturally acquired mucosal antibody levels to three Streptococcus pneumoniae (Spn) protein antigens, pneumococcal histidine triad protein D (PhtD), pneumococcal choline binding protein A (PcpA), and pneumolysin (Ply), and assesses the association of the mucosal antibody levels with occurrence of acute otitis media (AOM) caused by Spn. Both nasopharyngeal (NP) immunoglobulin G (IgG) and IgA levels to all three proteins slightly decreased in children from 6 to 9 months of age and then gradually increased through 24 months of age. Spn NP colonization was associated with higher mucosal antibody levels to all three proteins. However, children with Spn AOM had 5-8-fold lower IgG and 3-6-fold lower IgA levels to the three proteins than children without AOM but asymptomatically colonized with Spn. Antigen-specific antibody levels in the middle ear fluid (MEF) were correlated with antibody levels in the NP. Children with AOM caused by Spn had lower antibody levels in both the MEF and NP than children with AOM caused by other pathogens. These results indicate that higher naturally acquired mucosal antibody levels to PhtD, PcpA and Ply are associated with reduced AOM caused by Spn.

  15. Role of Helicobacter pylori specific heat shock protein-60 antibodies in the aetiology of coronary artery disease

    Directory of Open Access Journals (Sweden)

    Aruneshwari Dayal

    2012-01-01

    Full Text Available The role of chronic infections in causing coronary artery disease (CAD has been investigated for the past several years. Among them, the role of Helicobacter pylori has stimulated keen interest. Though initial results were conflicting, there are growing data to support the role of H. pylori in CAD. The main mechanism of endothelial damage is hypothesized to be through molecular mimicry involving heat shock proteins. This study was designed to determine the prevalence of H.pylori and cytotoxin associated gene A (cagA positive H.pylori infection in patients undergoing coronary artery bypass grafting (CABG and the potential role of anti-H. pylori specific heat shock protein-60 (Hp-HSP-60 antibody response in these patients, for cardiac events. One hundred patients undergoing CABG and 100 controls were studied. The H.pylori infection and cagA status were determined serologically by enzyme-linked immunosorbent assay (ELISA. Hp-HSP-60 Immunoglobulin G (IgG antibodies were estimated by using an in house ELISA. Although there was no difference in the prevalence of H.pylori infection in patients and controls (74% vs 70%, 58% of patients were infected with cagA positive H.pylori compared to 36% of controls (P=0.002. Mean systemic levels of Hp-HSP-60 IgG were also higher in patients than in controls (27.9 vs 18.7, P=0.0001. These antibody levels were also significantly higher in H.pylori positive patients (P=0.0001. There was a strong correlation between Hp-HSP-60 antibody levels and occurrence of myocardial infarction (P=0.003. CagA positive H.pylori infection may be associated with the development of CAD. High levels of Hp-HSP-60 antibodies may constitute a marker and/or concomitant pathogenic factor of the disease.

  16. Antibodies against the Plasmodium falciparum glutamate-rich protein from naturally exposed individuals living in a Brazilian malaria-endemic area can inhibit in vitro parasite growth

    DEFF Research Database (Denmark)

    Pratt-Riccio, Lilian Rose; Bianco, Cesare; Totino, Paulo Renato Rivas;

    2011-01-01

    The glutamate-rich protein (GLURP) is an exoantigen expressed in all stages of the Plasmodium falciparum life cycle in humans. Anti-GLURP antibodies can inhibit parasite growth in the presence of monocytes via antibody-dependent cellular inhibition (ADCI), and a major parasite-inhibitory region h...

  17. Construction and characterization of a fusion protein of single-chain anti-carcinoma antibody 323/A3 and human beta-glucuronidase

    NARCIS (Netherlands)

    Haisma, HJ; Brakenhoff, RH; Van der Meulen-Muileman, I.H.; Pinedo, HM; Boven, E

    1998-01-01

    We report the construction and expression of a fusion protein between a single-chain antibody specific for human carcinomas and human beta-glucuronidase by recombinant DNA technology. The sequences encoding the murine monoclonal antibody 323/A3 light- and heavy-chain variable genes were joined by a

  18. Human antibody responses to VlsE antigenic variation protein of Borrelia burgdorferi.

    Science.gov (United States)

    Lawrenz, M B; Hardham, J M; Owens, R T; Nowakowski, J; Steere, A C; Wormser, G P; Norris, S J

    1999-12-01

    VlsE is a 35-kDa surface-exposed lipoprotein of Borrelia burgdorferi that was shown previously to undergo antigenic variation through segmental recombination of silent vls cassettes with vlsE during experimental mouse infections. Previous data had indicated that sera from North American Lyme disease patients and experimentally infected animals contained antibodies reactive with VlsE. In this study, sera from patients with Lyme disease, syphilis, and autoimmune conditions as well as from healthy controls were examined for reactivity with VlsE by Western blotting and enzyme-linked immunosorbent assay (ELISA). Strong Western blot reactivity to a recombinant VlsE cassette region protein was obtained consistently with Lyme disease sera. Although sera from Lyme disease patients also reacted with a band corresponding to VlsE in B. burgdorferi B31-5A3, interpretation was complicated by low levels of VlsE expression in in vitro-cultured B. burgdorferi and by the presence of comigrating bands. An ELISA using recombinant VlsE was compared with an ELISA using sonically disrupted B. burgdorferi as the antigen. For a total of 93 Lyme disease patient sera examined, the VlsE ELISA yielded sensitivities of 63% for culture-confirmed erythema migrans cases and 92% for later stages, as compared to 61 and 98%, respectively, for the "whole-cell" ELISA. The specificities of the two assays with healthy blood donor sera were comparable, but the VlsE ELISA was 90% specific with sera from syphilis patients, compared to 20% specificity for the whole-cell ELISA with this group. Neither assay showed reactivity with a panel of sera from 20 non-Lyme disease arthritis patients or 20 systemic lupus erythematosus patients. Our results indicate that VlsE may be useful in the immunodiagnosis of Lyme disease and may offer greater specificity than ELISAs using whole B. burgdorferi as the antigen.

  19. A novel regulatory mechanism for whey acidic protein gene expression.

    OpenAIRE

    Chen, L.H.; Bissell, M J

    1989-01-01

    When primary mouse mammary epithelial cells (PMME) are cultured on a basement membrane type matrix, they undergo extensive morphogenesis leading to the formation of 3-dimensional alveoli-like spherical structures surrounding a closed lumen. We show for the first time that cells cultured on basement membrane-type matrix express high levels of whey acidic protein (WAP) mRNA and secrete the protein into the lumen. The expression of WAP appears to be dependent upon the formation of the alveoli-li...

  20. A fatty-acid-binding protein from wheat kernels

    OpenAIRE

    Castagnaro, Atilio; García Olmedo, Francisco

    1994-01-01

    A protein of about 7 kDa (W-FABP) has been isolated from mature wheat kernels by H2O extraction and gel filtration of the extract, followed by two steps of high-performance liquid chromatography. The N-terminal amino acid sequence has been determined up to the 28th residue and found to be identical (except for positions 4 and 5) to that deduced from a barley cDNA (EMBL X15257), which had been improperly classified as a non-specific lipid transfer protein (LTP2). Similarly with LTPs, W-FABP do...

  1. Substitution at aspartic acid 1128 in the SARS coronavirus spike glycoprotein mediates escape from a S2 domain-targeting neutralizing monoclonal antibody.

    Directory of Open Access Journals (Sweden)

    Oi-Wing Ng

    Full Text Available The Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV is the etiological agent for the infectious disease, SARS, which first emerged 10 years ago. SARS-CoV is a zoonotic virus that has crossed the species barriers to infect humans. Bats, which harbour a diverse pool of SARS-like CoVs (SL-CoVs, are believed to be the natural reservoir. The SARS-CoV surface Spike (S protein is a major antigenic determinant in eliciting neutralizing antibody production during SARS-CoV infection. In our previous work, we showed that a panel of murine monoclonal antibodies (mAbs that target the S2 subunit of the S protein are capable of neutralizing SARS-CoV infection in vitro (Lip KM et al, J Virol. 2006 Jan; 80(2: 941-50. In this study, we report our findings on the characterization of one of these mAbs, known as 1A9, which binds to the S protein at a novel epitope within the S2 subunit at amino acids 1111-1130. MAb 1A9 is a broadly neutralizing mAb that prevents viral entry mediated by the S proteins of human and civet SARS-CoVs as well as bat SL-CoVs. By generating mutant SARS-CoV that escapes the neutralization by mAb 1A9, the residue D1128 in S was found to be crucial for its interaction with mAb 1A9. S protein containing the substitution of D1128 with alanine (D1128A exhibited a significant decrease in binding capability to mAb 1A9 compared to wild-type S protein. By using a pseudotyped viral entry assay, it was shown that the D1128A substitution in the escape virus allows it to overcome the viral entry blockage by mAb 1A9. In addition, the D1128A mutation was found to exert no effects on the S protein cell surface expression and incorporation into virion particles, suggesting that the escape virus retains the same viral entry property as the wild-type virus.

  2. A recombinant antibody-interleukin 2 fusion protein suppresses growth of hepatic human neuroblastoma metastases in severe combined immunodeficiency mice.

    OpenAIRE

    Sabzevari, H; Gillies, S D; Mueller, B M; Pancook, J D; Reisfeld, R A

    1994-01-01

    A genetically engineered fusion protein consisting of a human/mouse chimeric anti-ganglioside GD2 antibody (ch14.18) and recombinant human interleukin 2 (rhIL-2) was tested for its ability to target rhIL-2 to tumor sites and stimulate immune effector cells sufficiently to achieve effective tumor cell lysis in vivo. The ch14.18-IL-2 fusion protein proved more effective than equivalent doses of rhIL-2 in suppressing dissemination and growth of human neuroblastoma in an experimental hepatic meta...

  3. Limbic Encephalitis Associated with Anti-γ-aminobutyric Acid B Receptor Antibodies: A Case Series from China

    Institute of Scientific and Technical Information of China (English)

    Hong-Zhi Guan; Hai-Tao Ren; Xun-Zhe Yang; Qiang Lu; Bin Peng; Yi-Cheng Zhu; Xiao-Qiu Shao

    2015-01-01

    Background: Autoimmune encephalitis associated with antibodies against γ-aminobutyric acid B receptor (GABABR) in patients with limbic encephalitis (LE) was first described in 2010.We present a series of Han Chinese patients for further clinical refinement.Methods: Serum and cerebrospinal fluid (CSF) samples from patients referred to the program of encephalitis and paraneoplastic syndrome of Peking Union Medical College Hospital were tested with indirect immunofluorescence.Clinical information of patients with anti-GABABR antibody positivity was retrospectively reviewed, and descriptive statistical analysis was performed.Results: All eighteen anti-GABABR antibody-positive cases had limbic syndromes, and electroencephalogram (EEG) or neuroimaging evidence fulfilled the diagnostic criteria of LE.Four patients had additional antibodies against Hu in serum and one had anti-N-methyl-d-aspartate receptor antibody in both sera and CSE Seventeen (17/18) patients presented with new-onset refractory seizure or status epileptics.Twelve (12/18) patients had memory deficits, 11 (11/18) patients had personality change, 7 (7/18) patients had disturbance of consciousness, and 3 (3/18) patients showed cerebellar dysfunction.One patient with LE had progressive motor and sensory polyneuropathy.Lung cancer was detected in 6 (6/18) patients.Ten (10/18) patients showed abnormality in bilateral or unilateral mediotemporal region on magnetic resonance imaging.Ten (10/18) patients had temporal lobe epileptic activity with or without general slowing on EEG.Seventeen patients received immunotherapy and 15 of them showed neurological improvement.Four patients with lung cancer died within 1-12 months due to neoplastic complications.Conclusions: Our study demonstrates that most Han Chinese patients with anti-GABABR antibody-associated LE have prominent refractory epilepsy and show neurological improvement on immunotherapy.Patients with underlying lung tumor have a relatively poor prognosis

  4. Topological features of proteins from amino acid residue networks

    CERN Document Server

    Alves, N A; Alves, Nelson Augusto; Martinez, Alexandre Souto

    2006-01-01

    Topological properties of native folds are obtained from statistical analysis of 160 low homology proteins covering the four structural classes. This is done analysing one, two and three-vertex joint distribution of quantities related to the corresponding network of amino acid residues. Emphasis on the amino acid residue hydrophobicity leads to the definition of their center of mass as vertices in this contact network model with interactions represented by edges. The network analysis helps us to interpret experimental results such as hydrophobic scales and fraction of buried accessible surface area in terms of the network connectivity. To explore the vertex type dependent correlations, we build a network of hydrophobic and polar vertices. This procedure presents the wiring diagram of the topological structure of globular proteins leading to the following attachment probabilities between hydrophobic-hydrophobic 0.424(5), hydrophobic-polar 0.419(2) and polar-polar 0.157(3) residues.

  5. Polyunsaturated Branched-Chain Fatty Acid Geranylgeranoic Acid Induces Unfolded Protein Response in Human Hepatoma Cells.

    Directory of Open Access Journals (Sweden)

    Chieko Iwao

    Full Text Available The acyclic diterpenoid acid geranylgeranoic acid (GGA has been reported to induce autophagic cell death in several human hepatoma-derived cell lines; however, the molecular mechanism for this remains unknown. In the present study, several diterpenoids were examined for ability to induce XBP1 splicing and/or lipotoxicity for human hepatoma cell lines. Here we show that three groups of diterpenoids emerged: 1 GGA, 2,3-dihydro GGA and 9-cis retinoic acid induce cell death and XBP1 splicing; 2 all-trans retinoic acid induces XBP1 splicing but little cell death; and 3 phytanic acid, phytenic acid and geranylgeraniol induce neither cell death nor XBP1 splicing. GGA-induced ER stress/ unfolded protein response (UPR and its lipotoxicity were both blocked by co-treatment with oleic acid. The blocking activity of oleic acid for GGA-induced XBP1 splicing was not attenuated by methylation of oleic acid. These findings strongly suggest that GGA at micromolar concentrations induces the so-called lipid-induced ER stress response/UPR, which is oleate-suppressive, and shows its lipotoxicity in human hepatoma cells.

  6. Preparation of Monoclonal Antibodies Against SpiC Protein Secreted by T3SS-2 of Salmonella spp.

    Science.gov (United States)

    Geng, Shizhong; Qian, Shanshan; Pan, Zhiming; Sun, Lin; Chen, Xiang; Jiao, Xinan

    2015-12-01

    SpiC protein, a member of Salmonella spp. type III secretion system (T3SS)-2, is necessary for the survival of Salmonella within macrophages, and it plays a vital role in Salmonella pathogenesis. To develop and test monoclonal antibodies (MAbs) against SpiC protein, two recombinant proteins, rHis-SpiC and rGST-SpiC, were expressed in vitro in the prokaryotic expression vectors pET-30(a) and pGEX-6p-1, respectively, and rHis-SpiC protein used to immunize mice. Hybridomas were generated from the splenocytes of these mice and the monoclonal antibodies produced by these cells were assessed using indirect enzyme-linked immunosorbent assay (ELISA) with rGST-SpiC as the coating antigen. An immunoblotting analysis indicated that all seven of the MAbs developed in this study could specifically recognize the SpiC protein. These MAbs will be very useful in the study of SpiC function and for use in the immunodiagnosis of Salmonella infection.

  7. Preparation of Monoclonal Antibodies Against SpiC Protein Secreted by T3SS-2 of Salmonella spp.

    Science.gov (United States)

    Geng, Shizhong; Qian, Shanshan; Pan, Zhiming; Sun, Lin; Chen, Xiang; Jiao, Xinan

    2015-12-01

    SpiC protein, a member of Salmonella spp. type III secretion system (T3SS)-2, is necessary for the survival of Salmonella within macrophages, and it plays a vital role in Salmonella pathogenesis. To develop and test monoclonal antibodies (MAbs) against SpiC protein, two recombinant proteins, rHis-SpiC and rGST-SpiC, were expressed in vitro in the prokaryotic expression vectors pET-30(a) and pGEX-6p-1, respectively, and rHis-SpiC protein used to immunize mice. Hybridomas were generated from the splenocytes of these mice and the monoclonal antibodies produced by these cells were assessed using indirect enzyme-linked immunosorbent assay (ELISA) with rGST-SpiC as the coating antigen. An immunoblotting analysis indicated that all seven of the MAbs developed in this study could specifically recognize the SpiC protein. These MAbs will be very useful in the study of SpiC function and for use in the immunodiagnosis of Salmonella infection. PMID:26683183

  8. Development of an automated mid-scale parallel protein purification system for antibody purification and affinity chromatography.

    Science.gov (United States)

    Zhang, Chi; Long, Alexander M; Swalm, Brooke; Charest, Ken; Wang, Yan; Hu, Jiali; Schulz, Craig; Goetzinger, Wolfgang; Hall, Brian E

    2016-12-01

    Protein purification is often a bottleneck during protein generation for large molecule drug discovery. Therapeutic antibody campaigns typically require the purification of hundreds of monoclonal antibodies (mAbs) during the hybridoma process and lead optimization. With the increase in high-throughput cloning, faster DNA sequencing, and the use of parallel protein expression systems, a need for high-throughput purification approaches has evolved, particularly in the midsize range between 20 ml and 100 ml. To address this we modified a four channel Gilson solid phase extraction system (referred to as MG-SPE) with switching valves and sample holding loops to be able to perform standard affinity purification using commercially available columns and micro-titer format deep well blocks. By running 4 samples in parallel, the MG-SPE has the capacity to purify up to 24 samples of greater than 50 ml each using a single-step affinity purification protocol or a two-step protocol consisting of affinity chromatography followed by desalting/buffer exchange overnight (∼12 h run time). Our evaluation of affinity purification using mAbs and Fc-fusion proteins from mammalian cell supernatants demonstrates that the MG-SPE compared favorably with industry standard systems for both protein quality and yield. Overall the system is simple to operate and fills a void in purification processes where a simple, efficient, automated system is needed for affinity purification of midsize research samples.

  9. Photo-CIDNP studies of amino acids and proteins

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, J.J

    2001-07-01

    The ultimate aim of the research described in this thesis is the development of methods with which ope may study the structure and function of proteins on a molecular level. This is done with the help of a combination of NMR (Nuclear Magnetic Resonance) and flash photolysis, in which light initiated reactions between a chromophore and an amino acid induce abnormal NMR intensities. Chapters 1, 2 and 3: In the first chapter, a brief introduction of CIDNP and its application to proteins is given, followed by a short description of each chapter. The second chapter is an introductory review, covering the basics of the NMR experiment in the first part, and the theory behind the CIDNP phenomenon in the second. Chapter three describes the experimental apparatus and methods. Chapter 4: Photosensitization The light initiated chemical reaction between photosensitizer and amino acid residue is studied in detail for the case of FMN (flavinmononucleotide) and the amino acids tyrosine, tryptophan and histidine. An introduction is given of further sensitizers which have been found to generate CIDNP on amino acids, and which are used in later chapters. Chapter 5: CIDNP of Amino Acids and Proteins The typical CIDNP spectra of the amino acids tyrosine, tryptophan and histidine are introduced and elucidated in the first half of this chapter. Photo-CIDNP on the proteins ribonuclease A and Hen Egg White Lysozyme with the photosensitizers FMN, thionin and eosin Y are described in the second half. Chapter 6: CIDNP in Micellar Solutions The presence of detergent, below and above the critical micelle concentration, is shown to affect CIDNP intensities, due to electrostatic interactions between charged dye and detergent molecules. In the last part of this chapter, photo-CIDNP experiments with the membrane protein gramicidin A, incorporated in detergent and lipid micelles, are described. Chapter 7: CIDNP Study of the Tryptophan Radical CIDNP spectra are characteristic of the transient radical

  10. The clinical significance of fatty acid binding proteins

    Directory of Open Access Journals (Sweden)

    Barbara Choromańska

    2011-11-01

    Full Text Available Excessive levels of free fatty acids are toxic to cells. The human body has evolved a defense mechanism in the form of small cytoplasmic proteins called fatty acid binding proteins (FABPs that bind long-chain fatty acids (LCFA, and then refer them to appropriate intracellular disposal sites (oxidation in mitochondria and peroxisomes or storage in the endoplasmic reticulum. So far, nine types of these proteins have been described, and their name refers to the place in which they were first identified or where they can be found in the greatest concentration. The most important FABPs were isolated from the liver (L-FABP, heart (H-FABP, intestine (I-FABP, brain (B-FABP, epidermis (E-FABP and adipocytes (A-FABP. Determination of H-FABP is used in the diagnosis of myocardial infarction, and L-FABP in kidney lesions of different etiologies. It is postulated that FABPs play an important role in the pathogenesis of metabolic diseases. Elevated levels of A-FABP have been found in the pericardial fat tissue and were associated with cardiac dysfunction in obese people. A rise in A-FABP has been observed in patients with type II diabetes. I-FABP is known as a marker of cell damage in the small intestine. Increased concentration of B-FABP has been associated with human brain tumors such as glioblastoma and astrocytoma, as well as with neurodegenerative diseases (Alzheimer’s, Parkinson’s and other disorders of cognitive function. The aim of this work was to present current data on the clinical significance of fatty acid binding proteins.

  11. 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.

  12. Preparation and Primary Application of Monoclonal Antibodies against a Novel Ribosome-inactivating Protein Moschatin from Pumpkin Seeds

    Institute of Scientific and Technical Information of China (English)

    Heng-Chuan XIA; Wei-Guo HU; Xin-Xiu YANG; Feng LI; Zu-Chuan ZHANG

    2004-01-01

    Plant ribosome-inactivating proteins (RIPs) have multiple biological functions, and have beenwidely used in the studies on biomedical and agronomic applications. Moschatin is a novel single-chain RIPrecently purified from pumpkin seeds, and it has been successfully applied to construct the immunotoxin thatcan selectively kill the cultured human melanoma cells. Six stable strains of hybridomas (2H8, 4A8, 5B6,6F8, 4H 10 and 6C2) that can secrete high specific monoclonal antibodies against Moschatin have beensuccessfully prepared using hybridoma technique. The isotypes of these monoclonal antibodies areIgG1, IgG1, IgG1, IgG1, IgG2a and IgM. Their affinity constants were determined to be 1.42×108, 2.71×108,8.72×107, 2.06×108, 1.36×108 and 1.51×108M-1 in a sequent order, measured by non-competitive ELISA.The monoclonal antibody 4A8 has been used to detect Moschatin in Western blot. An immunoaffinity gel,which consisted ofa monoclonal antibody 4H10 and Sepharose 4B, was prepared and used to purify Moschatinfrom pumpkin seeds crude extract.

  13. Preparation and Primary Application of Monoclonal Antibodies against a Novel Ribosome-inactivating Protein Moschatin from Pumpkin Seeds

    Institute of Scientific and Technical Information of China (English)

    Heng-ChuanXIA; Wei-GuoHU; Xin-XiuYANG; FengLI; Zu-ChuanZHANG

    2004-01-01

    Plant ribosome-inactivating proteins (RIPs) have multiple biological functions, and have beenwidely used in the studies on biomedical and agronomic applications. Moschatin is a novel single-chain RIPrecently purified from pumpkin seeds, and it has been successfully applied to construct the immunotoxin thatcan selectively kill the cultured human melanoma cells. Six stable strains of hybridomas (2H8, 4A8, 5B6,6F8, 4H10 and 6C2) that can secrete high specific monoclonal antibodies against Moschatin have beensuccessfully prepared using hybridoma technique. The isotypes of these monoclonal antibodies areIgG1, IgG1, IgG1, IgG1, IgG2a and IgM. Their affinity constants were determined to be 1.42×108, 2.71×108,8.72×07, 2.06×l08, 1.36×108 and 1.51×108 M-1 in a sequent order, measured by non-competitive ELISA.The monoclonal antibody 4A8 has been used to detect Moschatin in Western blot. An immunoaffinity gel,which consisted ofa monoclonal antibody 4H 10 and Sepharose 4B, was prepared and used to purify Moschatinfrom pumpkin seeds crude extract.

  14. Rational design and validation of an anti-protein kinase C active-state specific antibody based on conformational changes

    Science.gov (United States)

    Pena, Darlene Aparecida; Andrade, Victor Piana de; Silva, Gabriela Ávila Fernandes; Neves, José Ivanildo; Oliveira, Paulo Sergio Lopes de; Alves, Maria Julia Manso; Devi, Lakshmi A.; Schechtman, Deborah

    2016-01-01

    Protein kinase C (PKC) plays a regulatory role in key pathways in cancer. However, since phosphorylation is a step for classical PKC (cPKC) maturation and does not correlate with activation, there is a lack of tools to detect active PKC in tissue samples. Here, a structure-based rational approach was used to select a peptide to generate an antibody that distinguishes active from inactive cPKC. A peptide conserved in all cPKCs, C2Cat, was chosen since modeling studies based on a crystal structure of PKCβ showed that it is localized at the interface between the C2 and catalytic domains of cPKCs in an inactive kinase. Anti-C2Cat recognizes active cPKCs at least two-fold better than inactive kinase in ELISA and immunoprecipitation assays, and detects the temporal dynamics of cPKC activation upon receptor or phorbol stimulation. Furthermore, the antibody is able to detect active PKC in human tissue. Higher levels of active cPKC were observed in the more aggressive triple negative breast cancer tumors as compared to the less aggressive estrogen receptor positive tumors. Thus, this antibody represents a reliable, hitherto unavailable and a valuable tool to study PKC activation in cells and tissues. Similar structure-based rational design strategies can be broadly applied to obtain active-state specific antibodies for other signal transduction molecules. PMID:26911897

  15. Rational design and validation of an anti-protein kinase C active-state specific antibody based on conformational changes.

    Science.gov (United States)

    Pena, Darlene Aparecida; Andrade, Victor Piana de; Silva, Gabriela Ávila Fernandes; Neves, José Ivanildo; Oliveira, Paulo Sergio Lopes de; Alves, Maria Julia Manso; Devi, Lakshmi A; Schechtman, Deborah

    2016-02-25

    Protein kinase C (PKC) plays a regulatory role in key pathways in cancer. However, since phosphorylation is a step for classical PKC (cPKC) maturation and does not correlate with activation, there is a lack of tools to detect active PKC in tissue samples. Here, a structure-based rational approach was used to select a peptide to generate an antibody that distinguishes active from inactive cPKC. A peptide conserved in all cPKCs, C2Cat, was chosen since modeling studies based on a crystal structure of PKCβ showed that it is localized at the interface between the C2 and catalytic domains of cPKCs in an inactive kinase. Anti-C2Cat recognizes active cPKCs at least two-fold better than inactive kinase in ELISA and immunoprecipitation assays, and detects the temporal dynamics of cPKC activation upon receptor or phorbol stimulation. Furthermore, the antibody is able to detect active PKC in human tissue. Higher levels of active cPKC were observed in the more aggressive triple negative breast cancer tumors as compared to the less aggressive estrogen receptor positive tumors. Thus, this antibody represents a reliable, hitherto unavailable and a valuable tool to study PKC activation in cells and tissues. Similar structure-based rational design strategies can be broadly applied to obtain active-state specific antibodies for other signal transduction molecules.

  16. Hyperdimensional analysis of amino acid pair distributions in proteins.

    Directory of Open Access Journals (Sweden)

    Svend B Henriksen

    Full Text Available Our manuscript presents a novel approach to protein structure analyses. We have organized an 8-dimensional data cube with protein 3D-structural information from 8706 high-resolution non-redundant protein-chains with the aim of identifying packing rules at the amino acid pair level. The cube contains information about amino acid type, solvent accessibility, spatial and sequence distance, secondary structure and sequence length. We are able to pose structural queries to the data cube using program ProPack. The response is a 1, 2 or 3D graph. Whereas the response is of a statistical nature, the user can obtain an instant list of all PDB-structures where such pair is found. The user may select a particular structure, which is displayed highlighting the pair in question. The user may pose millions of different queries and for each one he will receive the answer in a few seconds. In order to demonstrate the capabilities of the data cube as well as the programs, we have selected well known structural features, disulphide bridges and salt bridges, where we illustrate how the queries are posed, and how answers are given. Motifs involving cysteines such as disulphide bridges, zinc-fingers and iron-sulfur clusters are clearly identified and differentiated. ProPack also reveals that whereas pairs of Lys residues virtually never appear in close spatial proximity, pairs of Arg are abundant and appear at close spatial distance, contrasting the belief that electrostatic repulsion would prevent this juxtaposition and that Arg-Lys is perceived as a conservative mutation. The presented programs can find and visualize novel packing preferences in proteins structures allowing the user to unravel correlations between pairs of amino acids. The new tools allow the user to view statistical information and visualize instantly the structures that underpin the statistical information, which is far from trivial with most other SW tools for protein structure analysis.

  17. Preparation of Monoclonal Antibody Against HPT and Its Application to Detecting Marker Protein in Genetically Modified Rice

    Institute of Scientific and Technical Information of China (English)

    LI-CHEN YANG; SU-XIANG ZHANG; GUO-HUA PI; YING-HUA LI; ZHEN ZHU; XIAO-GUANG YANG

    2005-01-01

    Objective To produce the monoclonal antibodies (mAbs) against hygromycin B phosphotransferase (HPT) and to develop immunoassay based on mAbs for biosafety assessment of HPT in genetically modified rice (GM rice). Methods BALB/c mice were immunized with purified recombinant 6His. HPT protein, and the conventional hybridoma technology was used to generate the monoclonal hybridoma cells. ELISA and Western blot were used to analyze the specificity of mAbs recognizing HPT and the cross reaction with other proteins. A double-Ab sandwich ELISA method was established to detect HPT expression level in the sck gene-modified rice plants. Results Four hybridomas, named F1, D4-2, D4-4, and D4-5, producing the mAbs against HPT were successfully obtained with the titer of ascetic mAbs ranging from 1×10-4 to 1×10-5. Identification of subclass showed that all the produced mAbs belonged to IgG1. Western blot showed specific binding reaction between the mAbs to the HPT proteins expressed in the GM rice. A double sandwich ELISA coated with anti-HPT polyclonal antibody was established with mAbs as sandwich antibody, which showed a sensitivity of 30ng/mL and did not crossreact with other proteins. The expression level of HPT in the leaves of sck-transformed lines was detected (80-150ng/mL). But HPT protein in the grain and seed of GM rice could not be detected using this ELISA assay. Conclusion Anti-HPT mAbs prepared herein have a high specificity and can be used for rapid assay of HPT antigen. The expression level of HPT in the GM rice grain and seed is lower than our ELISA detection limit.

  18. 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.

  19. Mouse whey acidic protein is a novel member of the family of 'four-disulfide core' proteins.

    OpenAIRE

    Hennighausen, L G; Sippel, A E

    1982-01-01

    Unlike in other mammalian species, the major whey protein in mouse is not alpha-lactalbumin, but a cysteine rich, acidic protein with a molecular weight of 14.0 kDa. We have deduced the amino acid sequence of this mouse acidic of whey protein from the nucleotide sequence of cloned cDNA. The positions of the half cysteines suggest that mouse whey acidic protein (WAP) is a two domain protein, very similar in structure to the plant lectin wheat germ agglutinin and the hypothalamic carrier protei...

  20. No evidence for XMRV nucleic acids, infectious virus or anti-XMRV antibodies in Canadian patients with chronic fatigue syndrome.

    Directory of Open Access Journals (Sweden)

    Imke Steffen

    Full Text Available The gammaretroviruses xenotropic murine leukemia virus (MLV-related virus (XMRV and MLV have been reported to be more prevalent in plasma and peripheral blood mononuclear cells of chronic fatigue syndrome (CFS patients than in healthy controls. Here, we report the complex analysis of whole blood and plasma samples from 58 CFS patients and 57 controls from Canada for the presence of XMRV/MLV nucleic acids, infectious virus, and XMRV/MLV-specific antibodies. Multiple techniques were employed, including nested and qRT-PCR, cell culture, and immunoblotting. We found no evidence of XMRV or MLV in humans and conclude that CFS is not associated with these gammaretroviruses.

  1. Cost Savings Associated with Testing of Antibodies, Antigens, and Nucleic Acids for Diagnosis of Acute HIV Infection

    OpenAIRE

    Karris, Maile Y.; Anderson, Christy M.; Sheldon R. Morris; Smith, Davey M.; Little, Susan J.

    2012-01-01

    Efforts to identify all persons infected with HIV in the United States are driven by the hope that early diagnosis will lower risk behaviors and decrease HIV transmission. Identification of HIV-infected people earlier in the course of their infection with HIV antigen/antibody (Ag/Ab) combination assays (4th-generation HIV assays) should help achieve this goal. We compared HIV RNA nucleic acid test (NAT) results to the results of a 4th-generation Ag/Ab assay (Architect HIV Ag/Ab Combo [HIV Com...

  2. Protein evolution via amino acid and codon elimination

    DEFF Research Database (Denmark)

    Goltermann, Lise; Larsen, Marie Sofie Yoo; Banerjee, Rajat;

    2010-01-01

    correlation between the number of residues randomized and the size of the resulting ensemble. Using GFP as the model protein, we present a strategy, termed protein evolution via amino acid and codon elimination, through which simplified, native-like polypeptides encoded by a reduced genetic code were obtained...... via screening of reduced-size ensembles. METHODOLOGY/PRINCIPAL FINDINGS: The strategy involves combining a sequential mutagenesis scheme to reduce library size with structurally stabilizing mutations, chaperone complementation, and reduced temperature of gene expression. In six steps, we eliminated...... a common buried residue, Phe, from the green fluorescent protein (GFP), while retaining activity. A GFP variant containing 11 Phe residues was used as starting scaffold to generate 10 separate variants in which each Phe was replaced individually (in one construct two adjacent Phe residues were changed...

  3. An antibody to de-N-acetyl sialic acid containing-polysialic acid identifies an intracellular antigen and induces apoptosis in human cancer cell lines.

    Directory of Open Access Journals (Sweden)

    Lindsay M Steirer

    Full Text Available Polysialic acid (PSA, an α2,8-linked homopolymer of N-acetylneuraminic acid (Neu5Ac, is developmentally regulated and its expression is thought to be restricted to a few tissues in adults. Recently, we showed that two human pathogens expressed a derivative of PSA containing de-N-acetyl sialic acid residues (NeuPSA. Here we show that an epitope identified by the anti-NeuPSA monoclonal antibody, SEAM 3 (SEAM 3-reactive antigen or S3RA, is expressed in human melanomas, and also intracellularly in a human melanoma cell line (SK-MEL-28, a human T cell leukemia cell line (Jurkat, and two neuroblastoma cell lines (CHP-134 and SH-SY5Y. SEAM 3 binding induced apoptosis in the four cell lines tested. The unusual intracellular distribution of S3RA was similar to that described for the PSA polysialyltransferases, STX and PST, which are also expressed in the four cell lines used here. Interestingly, suppression of PST mRNA expression by transfection of SK-MEL-28 cells with PST-specific short interfering RNA (siRNA resulted in decreased SEAM 3 binding. The results suggest further studies of the utility of antibodies such as SEAM 3 as therapeutic agents for certain malignancies.

  4. Construction of a prokaryotic expression system of vacA gene and detection of vatA gene,VacA protein in Helicobacter pylori isolates and ant-VacA antibody in patients'sera

    Institute of Scientific and Technical Information of China (English)

    Jie Yan; Ya-Fei Mao

    2004-01-01

    AIM: To construct a recombinant prokaryotic expression vector inserted with Helicobacter pylori vacA gene and identify the immunity of the expressed recombinant protein,and to determine prevalence of vacA-carryinglVacA expressing Hpyloriisolates and seroprevalence of specific ant-VacA antibody in H pyloriinfected patients.METHODS: Polymerase chain reaction technique was used to amplify complete vacA gene of H pyloristrain NCTC11637 and to detect vacA gene in 109 H pylori isolates. The amplification product of the complete vacA gene was sequenced after T-A cloning. A recombinant expression vector inserted with a complete vacA gene fragment, named as pET32a-vacA, was constructed. Expression of the target recombinant protein VacA (rVacA) was examined by SDSPAGE. Western blot using commercial antibodies against whole cell of H pyloriand an immunodiffusion assay using self-prepared rabbit anti-rVacA antibody were applied to determine immunoreaction and antigenicity of rVacA. Two ELISA methods were established to detect VacA expression in H pyloriisolates and the specific anti-VacA antibody in sera from 125 patients infected with H pylori.RESULTS: In comparison with the reported corresponding sequences, homologies of nucleotide and putative amino acid sequences of the cloned vacA gene were 99.82% and 100%, respectively. The constructed recombinant prokaryotic expression system efficiently produced rVacA. rVacA was able to combine with the commercial antibodies against whole cell of H pyloriand to induce the immunized rabbit to produce specific antibody with an immunodiffusion titer of 1:4. All tested H pyloriisolates carried vacA gene, but only 66.1% expressed Vac A protein. Of the serum samples tested,42.4% were positive for specific anti-VacA antibody.CONCLUSION: A prokaryotic expression system of H pylori vacA gene was successfully constructed. The expressed rVacA can be used to detect specific anti-VacA antibody in human and to prepare antiserum in animals. The high

  5. Direct protein-protein interactions and substrate channeling between cellular retinoic acid binding proteins and CYP26B1.

    Science.gov (United States)

    Nelson, Cara H; Peng, Chi-Chi; Lutz, Justin D; Yeung, Catherine K; Zelter, Alex; Isoherranen, Nina

    2016-08-01

    Cellular retinoic acid binding proteins (CRABPs) bind all-trans-retinoic acid (atRA) tightly. This study aimed to determine whether atRA is channeled directly to cytochrome P450 (CYP) CYP26B1 by CRABPs, and whether CRABPs interact directly with CYP26B1. atRA bound to CRABPs (holo-CRABP) was efficiently metabolized by CYP26B1. Isotope dilution experiments showed that delivery of atRA to CYP26B1 in solution was similar with or without CRABP. Holo-CRABPs had higher affinity for CYP26B1 than free atRA, but both apo-CRABPs inhibited the formation of 4-OH-RA by CYP26B1. Similar protein-protein interactions between soluble binding proteins and CYPs may be important for other lipophilic CYP substrates.

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

    Directory of Open Access Journals (Sweden)

    Encheng Sun

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

  7. Generation of Monoclonal Antibodies against Dengue Virus Type 4 and Identification of Enhancing Epitopes on Envelope Protein.

    Directory of Open Access Journals (Sweden)

    Chung-Tao Tang

    Full Text Available The four serotypes of dengue virus (DENV1-4 pose a serious threat to global health. Cross-reactive and non-neutralizing antibodies enhance viral infection, thereby exacerbating the disease via antibody-dependent enhancement (ADE. Studying the epitopes targeted by these enhancing antibodies would improve the immune responses against DENV infection. In order to investigate the roles of antibodies in the pathogenesis of dengue, we generated a panel of 16 new monoclonal antibodies (mAbs against DENV4. Using plaque reduction neutralization test (PRNT, we examined the neutralizing activity of these mAbs. Furthermore, we used the in vitro and in vivo ADE assay to evaluate the enhancement of DENV infection by mAbs. The results indicate that the cross-reactive and poorly neutralizing mAbs, DD11-4 and DD18-5, strongly enhance DENV1-4 infection of K562 cells and increase mortality in AG129 mice. The epitope residues of these enhancing mAbs were identified using virus-like particle (VLP mutants. W212 and E26 are the epitope residues of DD11-4 and DD18-5, respectively. In conclusion, we generated and characterized 16 new mAbs against DENV4. DD11-4 and D18-5 possessed non-neutralizing activities and enhanced viral infection. Moreover, we identified the epitope residues of enhancing mAbs on envelope protein. These results may provide useful information for development of safe dengue vaccine.

  8. Characterization of a fatty acid-binding protein from rat heart.

    Science.gov (United States)

    Offner, G D; Troxler, R F; Brecher, P

    1986-04-25

    A fatty acid-binding protein has been isolated from rat heart and purified by gel filtration chromatography on Sephadex G-75 and anion-exchange chromatography on DE52. The circular dichroic spectrum of this protein was not affected by protein concentration, suggesting that it does not aggregate into multimers. Computer analyses of the circular dichroic spectrum predicted that rat heart fatty acid-binding protein contains approximately 22% alpha-helix, 45% beta-form and 33% unordered structure. Immunological studies showed that the fatty acid-binding proteins from rat heart and rat liver are immunochemically unrelated. The amino acid composition and partial amino acid sequence of the heart protein indicated that it is structurally related to, but distinct from, other fatty acid-binding proteins from liver, intestine, and 3T3 adipocytes. Using a binding assay which measures the transfer of fatty acids between donor liposomes and protein (Brecher, P., Saouaf, R., Sugarman, J. M., Eisenberg, D., and LaRosa, K. (1984) J. Biol. Chem. 259, 13395-13401), it was shown that both rat heart and liver fatty acid-binding proteins bind 2 mol of oleic acid or palmitic acid/mol of protein. The structural and functional relationship of rat heart fatty acid-binding protein to fatty acid-binding proteins from other tissues is discussed. PMID:3957934

  9. Analysis of protein-nucleic acid interactions by photochemical cross-linking and mass spectrometry

    DEFF Research Database (Denmark)

    Steen, Hanno; Jensen, Ole Nørregaard

    2002-01-01

    Photochemical cross-linking is a commonly used method for studying the molecular details of protein-nucleic acid interactions. Photochemical cross-linking aids in defining nucleic acid binding sites of proteins via subsequent identification of cross-linked protein domains and amino acid residues....

  10. Human Lyme arthritis and the immunoglobulin G antibody response to the 37-kilodalton arthritis-related protein of Borrelia burgdorferi.

    Science.gov (United States)

    Salazar, Carlos A; Rothemich, Monika; Drouin, Elise E; Glickstein, Lisa; Steere, Allen C

    2005-05-01

    In Borrelia burgdorferi-infected C3H-scid mice, antiserum to a differentially expressed, 37-kDa spirochetal outer-surface protein, termed arthritis-related protein (Arp), has been shown to prevent or reduce the severity of arthritis. In this study, we determined the immunoglobulin G (IgG) antibody responses to this spirochetal protein in single serum samples from 124 antibiotic-treated human patients with early or late manifestations of Lyme disease and in serial serum samples from 20 historic, untreated patients who were followed longitudinally from early infection through the period of arthritis. These 20 patients were representative of the spectrum of the severity and duration of Lyme arthritis. Among the 124 antibiotic-treated patients, 53% with culture-proven erythema migrans (EM) had IgG responses to recombinant glutathione S-transferase (GST)-Arp, as did 59% of the patients with facial palsy and 68% of those with Lyme arthritis. In addition, 75 to 80% of the 20 past, untreated patients had reactivity with this protein when EM was present, during initial episodes of joint pain, or during the maximal period of arthritis. There was no association at any of these three time points between GST-Arp antibody levels and the severity of the maximal attack of arthritis or the total duration of arthritis. Thus, after the first several weeks of infection, 60 to 80% of patients had IgG antibody responses to GST-Arp, but this response did not correlate with the severity or duration of Lyme arthritis.

  11. Biochemical and structural characterization of the interface mediating interaction between the influenza A virus non-structural protein-1 and a monoclonal antibody

    Science.gov (United States)

    Wu, Jianping; Mok, Chee-Keng; Chow, Vincent Tak Kwong; Yuan, Y. Adam; Tan, Yee-Joo

    2016-01-01

    We have previously shown that a non-structural protein 1 (NS1)-binding monoclonal antibody, termed as 2H6, can significantly reduce influenza A virus (IAV) replication when expressed intracellularly. In this study, we further showed that 2H6 binds stronger to the NS1 of H5N1 than A/Puerto Rico/8/1934(H1N1) because of an amino acid difference at residue 48. A crystal structure of 2H6 fragment antigen-binding (Fab) has also been solved and docked onto the NS1 structure to reveal the contacts between specific residues at the interface of antibody-antigen complex. In one of the models, the predicted molecular contacts between residues in NS1 and 2H6-Fab correlate well with biochemical results. Taken together, residues N48 and T49 in H5N1 NS1 act cooperatively to maintain a strong interaction with mAb 2H6 by forming hydrogen bonds with residues found in the heavy chain of the antibody. Interestingly, the pandemic H1N1-2009 and the majority of seasonal H3N2 circulating in humans since 1968 has N48 in NS1, suggesting that mAb 2H6 could bind to most of the currently circulating seasonal influenza A virus strains. Consistent with the involvement of residue T49, which is well-conserved, in RNA binding, mAb 2H6 was also found to inhibit the interaction between NS1 and double-stranded RNA. PMID:27633136

  12. An automated packed protein G micro-pipette tip assay for rapid quantification of polyclonal antibodies in ovine serum.

    Science.gov (United States)

    Chhatre, Sunil; Francis, Richard; Bracewell, Daniel G; Titchener-Hooker, Nigel J

    2010-11-15

    The demands on the biopharmaceutical sector to expedite process development have instigated the deployment of micro-biochemical engineering techniques to acquire manufacturing insight with extremely small sample volumes. In conjunction with automated liquid handlers, this permits the simultaneous evaluation of multiple operating conditions and reduces manual intervention. For these benefits to be sustained, novel ways are now required to accelerate analysis and so prevent this becoming a throughput bottleneck. For example, although Protein G HPLC is used to quantify antibody titres in bioprocess feedstocks, it can be time-consuming owing to the serial nature of its application. Although commercial options are available that can process many samples simultaneously, these require separate, potentially expensive instruments. A more integrated approach is desirable wherein the assay is implemented directly on a robot. This article describes a high-throughput alternative to antibody HPLC analysis which uses an eight-channel liquid handler to control pipette tips packed with 40 μL of Protein G affinity matrix. The linearity, range, limit of detection, specificity and precision of the method were established, with results showing that antibody was detected reliably and specifically between 0.10 and 1.00 mg/mL. Subsequently, the technique was used to quantify the antibody titre in ovine serum, which is used as feed material by BTG PLC for manufacturing FDA-approved polyclonal bio-therapeutics. The mean concentration determined by the tips was comparable to that found by HPLC, but the tip method delivered its results in less than 40% of the time and with the potential for further, substantial time-savings possible by using higher capacity robots.

  13. The bioactivity of teleost IL-6: IL-6 protein in orange-spotted grouper (Epinephelus coioides) induces Th2 cell differentiation pathway and antibody production.

    Science.gov (United States)

    Chen, Hsin-Hung; Lin, Han-Tso; Foung, Yi-Fan; Han-You Lin, John

    2012-10-01

    Interleukin 6 (IL-6) is a protein secreted by T cells and macrophages and plays an important role in immune response. IL-6 regulates the proliferation and differentiation of T cells, and elicits immunoglobulin production in B cells. In this study, the cDNA il-6 (gil-6) sequence of the orange spotted grouper (Epinephelus coioides) was obtained. The deduced IL-6 (gIL-6) protein comprised 223 amino acids, the sequence shared approximately 30% similarity with mammalian IL-6, and between 47% and 69% similarity with other available teleost IL-6. The protein comprises the signal peptide, the IL-6 family signature, and conserved amino acid residues found in IL-6 sequences of other teleost. In order to understand the bioactivity and influence of gIL-6 on humoral immune response, recombinant gIL-6 (rgIL-6) synthesized by prokaryotes was injected into orange spotted groupers, and the immune-related gene expression at various times in various organs was observed. Our results revealed that the Th1 specific transcription factor t-bet was down-regulated and Th2 specific transcription factors gata3, and c-maf were up-regulated in immune organs, following IL-6 stimulation. Additionally, higher levels of igm mRNA and translated protein were detected in rgIL-6 stimulated fish. These results indicate that IL-6 in groupers regulates the differentiation of naїve T helper cells into Th2 cells and elicits the production of antibodies.

  14. Vaccination of Sheep with a Methanogen Protein Provides Insight into Levels of Antibody in Saliva Needed to Target Ruminal Methanogens.

    Science.gov (United States)

    Subharat, Supatsak; Shu, Dairu; Zheng, Tao; Buddle, Bryce M; Kaneko, Kan; Hook, Sarah; Janssen, Peter H; Wedlock, D Neil

    2016-01-01

    Methane is produced in the rumen of ruminant livestock by methanogens and is a major contributor to agricultural greenhouse gases. Vaccination against ruminal methanogens could reduce methane emissions by inducing antibodies in saliva which enter the rumen and impair ability of methanogens to produce methane. Presently, it is not known if vaccination can induce sufficient amounts of antibody in the saliva to target methanogen populations in the rumen and little is known about how long antibody in the rumen remains active. In the current study, sheep were vaccinated twice at a 3-week interval with a model methanogen antigen, recombinant glycosyl transferase protein (rGT2) formulated with one of four adjuvants: saponin, Montanide ISA61, a chitosan thermogel, or a lipid nanoparticle/cationic liposome adjuvant (n = 6/formulation). A control group of sheep (n = 6) was not vaccinated. The highest antigen-specific IgA and IgG responses in both saliva and serum were observed with Montanide ISA61, which promoted levels of salivary antibodies that were five-fold higher than the second most potent adjuvant, saponin. A rGT2-specific IgG standard was used to determine the level of rGT2-specific IgG in serum and saliva. Vaccination with GT2/Montanide ISA61 produced a peak antibody concentration of 7 × 1016 molecules of antigen-specific IgG per litre of saliva, and it was estimated that in the rumen there would be more than 104 molecules of antigen-specific IgG for each methanogen cell. Both IgG and IgA in saliva were shown to be relatively stable in the rumen. Salivary antibody exposed for 1-2 hours to an in vitro simulated rumen environment retained approximately 50% of antigen-binding activity. Collectively, the results from measuring antibody levels and stablility suggest a vaccination-based mitigation strategy for livestock generated methane is in theory feasible. PMID:27472482

  15. Variability of DNA structure and protein-nucleic acid reconginition

    Directory of Open Access Journals (Sweden)

    Shestopalova A. V.

    2010-09-01

    Full Text Available Revealing molecular mechanisms of sequence-specific recognition of DNA by proteins is one of the key tasks of biology. The current review presents the results of statistical analysis of the structural databases obtained by different scientific groups studying the conformational features of free and protein-bound DNA fragments that could be used for clarifying the mechanisms of protein-nucleic acid recognition. The analysis of the published data allowed us to make the following generalizations. The ability of DNA double helix to adopt alternative conformations, including the ones of sugarphosphate backbone, is an intrinsic characteristic of certain DNA sequences. Such conformational transitions are the potential sources of formation of unique geometry of the dinucleotide steps and/or individual nucleotides and lead to alteration of base stacking and/or changes of the assessable surface area of atoms, and can be the criteria of recognition of DNA by protein as well. Changes in the physical properties that depend on the DNA structure, i. e. the polar/unpolar profile and electrostatic potential of the grooves, can also be used by protein for DNA readout.

  16. Retinoic acid binding protein in normal and neopolastic rat prostate.

    Science.gov (United States)

    Gesell, M S; Brandes, M J; Arnold, E A; Isaacs, J T; Ueda, H; Millan, J C; Brandes, D

    1982-01-01

    Sucrose density gradient analysis of cytosol from normal and neoplastic rat prostatic tissues exhibited a peak of (3H) retinoic acid binding in the 2S region, corresponding to the cytoplasmic retinoic acid binding protein (cRABP). In the Fisher-Copenhagen F1 rat, cRABP was present in the lateral lobe, but could not be detected in the ventral nor in the dorsal prostatic lobes. Four sublines of the R-3327 rat prostatic tumor contained similar levels of this binding protein. The absence of cRABP in the normal tissue of origin of the R-3327 tumor, the rat dorsal prostate, and reappearance in the neoplastic tissues follows a pattern described in other human and animal tumors. The occurrence of cRABP in the well-differentiated as well as in the anaplastic R-3327 tumors in which markers which reflect a state of differentiation and hormonal regulation, such as androgen receptor, 5 alpha reductase, and secretory acid phosphatase are either markedly reduced or absent, points to cRABP as a marker of malignant transformation.

  17. Development of a stable low-dose aglycosylated antibody formulation to minimize protein loss during intravenous administration

    Science.gov (United States)

    Morar-Mitrica, Sorina; Puri, Manasi; Beumer Sassi, Alexandra; Fuller, Joshua; Hu, Ping; Crotts, George; Nesta, Douglas

    2015-01-01

    The physical and chemical integrity of a biopharmaceutical must be maintained not only during long-term storage but also during administration. Specifically for the intravenous (i.v.) delivery of a protein drug, loss of stability can occur when the protein formulation is compounded with i.v. bag diluents, thus modifying the original composition of the drug product. Here we present the challenges associated with the delivery of a low-dose, highly potent monoclonal antibody (mAb) via the i.v. route. Through parallel in-use stability studies and conventional formulation development, a drug product was developed in which adsorptive losses and critical oxidative degradation pathways were effectively controlled. This development approach enabled the i.v. administration of clinical doses in the range of 0.1 to 0.5 mg total protein, while ensuring liquid drug product storage stability under refrigerated conditions. PMID:26073995

  18. Analysis of Salicylic Acid Induced Proteins in Rice

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    An analysis using SDS-PAGE of acidic and basic protein fractions extracted from rice seedling treated with salicylic acid (SA) yielded several new proteins, some of which are similar in relative molecular mass to PR-1a,c, PR-2, 2e and PR-3d, 3e of tobacco.Direct assays for peroxidases and β-1,3-glucanases demonstrated that the activities of the two enzymes in the rice seedlings increased rapidly with time after SA treatment, reaching a maximum 6 days after treatment.Disease resistance tests showed that SA treated rice seedlings stunted the development of blight lesions and displayed higher resistance to rice blight pathogen (Xanthomonas oryzea pv.oryzea).The data suggest that the treatment with SA, even for plants with high endogenous SA levels such as rice, may induce the appearance of new proteins and the formation of disease resistance.The results contribute to the analysis of the SA role in rice systemic acquired resistance.

  19. Human Skeletal Muscle Protein Metabolism Responses to Amino Acid Nutrition.

    Science.gov (United States)

    Mitchell, W Kyle; Wilkinson, Daniel J; Phillips, Bethan E; Lund, Jonathan N; Smith, Kenneth; Atherton, Philip J

    2016-07-01

    Healthy individuals maintain remarkably constant skeletal muscle mass across much of adult life, suggesting the existence of robust homeostatic mechanisms. Muscle exists in dynamic equilibrium whereby the influx of amino acids (AAs) and the resulting increases in muscle protein synthesis (MPS) associated with the intake of dietary proteins cancel out the efflux of AAs from muscle protein breakdown that occurs between meals. Dysregulated proteostasis is evident with aging, especially beyond the sixth decade of life. Women and men aged 75 y lose muscle mass at a rate of ∼0.7% and 1%/y, respectively (sarcopenia), and lose strength 2- to 5-fold faster (dynapenia) as muscle "quality" decreases. Factors contributing to the disruption of an otherwise robust proteostatic system represent targets for potential therapies that promote healthy aging. Understanding age-related impairments in anabolic responses to AAs and identifying strategies to mitigate these factors constitute major areas of interest. Numerous studies have aimed to identify 1) the influence of distinct protein sources on absorption kinetics and muscle anabolism, 2) the latency and time course of MPS responses to protein/AAs, 3) the impacts of protein/AA intake on muscle microvascular recruitment, and 4) the role of certain AAs (e.g., leucine) as signaling molecules, which are able to trigger anabolic pathways in tissues. This review aims to discuss these 4 issues listed, to provide historical and modern perspectives of AAs as modulators of human skeletal muscle protein metabolism, to describe how advances in stable isotope/mass spectrometric approaches and instrumentation have underpinned these advances, and to highlight relevant differences between young adults and older individuals. Whenever possible, observations are based on human studies, with additional consideration of relevant nonhuman studies. PMID:27422520

  20. Increased humoral antibody response of foot-and-mouth disease virus vaccine in growing pigs pre-treated with poly-γ-glutamic acid.

    Science.gov (United States)

    Lee, Jee-Hoon; Kang, Ik-Jae; Kim, A-Reum; Noh, You-Sun; Chung, Hee-Chun; Park, Bong-Kyun

    2016-06-30

    This study was conducted to determine if humoral antibody response of foot-and-mouth disease (FMD) vaccine improved in 8-week-old growing pigs born to well-vaccinated sows pre-treated with 60 mg of poly-γ-glutamic acid (γ-PGA) three days before vaccination. Antibody against FMD virus serotype O was measured 0, 2, 4 and 6 weeks post-vaccination, using a PrioCHECK FMDV type O ELISA kit. The results showed that positive antibody reactions against FMDV serotype O antigen among a component of the vaccine significantly increased in response to pre-injection with γ-PGA. PMID:26645341

  1. Increased humoral antibody response of foot-and-mouth disease virus vaccine in growing pigs pre-treated with poly-γ-glutamic acid

    Science.gov (United States)

    Lee, Jee-Hoon; Kang, Ik-Jae; Kim, A-Reum; Noh, You-Sun; Chung, Hee-Chun

    2016-01-01

    This study was conducted to determine if humoral antibody response of foot-and-mouth disease (FMD) vaccine improved in 8-week-old growing pigs born to well-vaccinated sows pre-treated with 60 mg of poly-γ-glutamic acid (γ-PGA) three days before vaccination. Antibody against FMD virus serotype O was measured 0, 2, 4 and 6 weeks post-vaccination, using a PrioCHECK FMDV type O ELISA kit. The results showed that positive antibody reactions against FMDV serotype O antigen among a component of the vaccine significantly increased in response to pre-injection with γ-PGA. PMID:26645341

  2. Amino acid profiles and digestible indispensable amino acid scores of proteins from the prioritized key foods in Bangladesh.

    Science.gov (United States)

    Shaheen, Nazma; Islam, Saiful; Munmun, Sarah; Mohiduzzaman, Md; Longvah, Thingnganing

    2016-12-15

    Concentrations of standard amino acids were determined in the composite samples (representing 30 agro-ecological zones of Bangladesh) of six prioritized key dietary protein sources: Oryza sativa (rice), Triticum aestivum (wheat flour), Lens culinaris (lentils), Pangusius pangusius (pangas), Labeo rohita (rohu) and Oreochromis mossambicus (tilapia). Digestible indispensable amino acid scores (DIAAS) was calculated using published data on amino acids' digestibility to evaluate the protein quality of these foods. Indispensable amino acid (IAA) contents (mg IAA/g protein), found to be highest in pangas (430) and lowest in wheat (336), of all these analyzed foods exceeded the FAO recommended daily allowance (277mg IAA/g protein) and contributed on average 40% to total amino acid contents. Untruncated DIAAS values ranged from 51% (lysine) in wheat to 106% (histidine) in pangas and distinguished pangas, rohu, and tilapia containing 'excellent quality' protein (DIAAS>100%) with potential to complement lower quality protein of cereals, fruits, and vegetables. PMID:27451158

  3. Methods and devices for protein assays

    Energy Technology Data Exchange (ETDEWEB)

    Chhabra, Swapnil (San Jose, CA); Cintron, Jose M. (Indianapolis, IN); Shediac, Renee (Oakland, CA)

    2009-11-03

    Methods and devices for protein assays based on Edman degradation in microfluidic channels are disclosed herein. As disclosed, the cleaved amino acid residues may be immobilized in an array format and identified by detectable labels, such as antibodies, which specifically bind given amino acid residues. Alternatively, the antibodies are immobilized in an array format and the cleaved amino acids are labeled identified by being bound by the antibodies in the array.

  4. Characterization of a monoclonal antibody to a novel glycan-dependent epitope in the V1/V2 domain of the HIV-1 envelope protein, gp120.

    Science.gov (United States)

    Doran, Rachel C; Morales, Javier F; To, Briana; Morin, Trevor J; Theolis, Richard; O'Rourke, Sara M; Yu, Bin; Mesa, Kathryn A; Berman, Phillip W

    2014-11-01

    Recent studies have described several broadly neutralizing monoclonal antibodies (bN-mAbs) that recognize glycan-dependent epitopes (GDEs) in the HIV-1 envelope protein, gp120. These were recovered from HIV-1 infected subjects, and several (e.g., PG9, PG16, CH01, CH03) target glycans in the first and second variable (V1/V2) domain of gp120. The V1/V2 domain is thought to play an important role in conformational masking, and antibodies to the V1/V2 domain were recently identified as the only immune response that correlated with protection in the RV144 HIV-1 vaccine trial. While the importance of antibodies to polymeric glycans is well established for vaccines targeting bacterial diseases, the importance of antibodies to glycans in vaccines targeting HIV has only recently been recognized. Antibodies to GDEs may be particularly significant in HIV vaccines based on gp120, where 50% of the molecular mass of the envelope protein is contributed by N-linked carbohydrate. However, few studies have reported antibodies to GDEs in humans or animals immunized with candidate HIV-1 vaccines. In this report, we describe the isolation of a mouse mAb, 4B6, after immunization with the extracellular domain of the HIV-1 envelope protein, gp140. Epitope mapping using glycopeptide fragments and in vitro mutagenesis showed that binding of this antibody depends on N-linked glycosylation at asparagine N130 (HXB2 numbering) in the gp120 V1/V2 domain. Our results demonstrate that, in addition to natural HIV-1 infection, immunization with recombinant proteins can elicit antibodies to the GDEs in the V1/V2 domain of gp120. Although little is known regarding conditions that favor antibody responses to GDEs, our studies demonstrate that these antibodies can arise from a short-term immunization regimen. Our results suggest that antibodies to GDEs are more common than previously suspected, and that further analysis of antibody responses to the HIV-1 envelope protein will lead to the discovery of

  5. Discovery and validation of an INflammatory PROtein-driven GAstric cancer Signature (INPROGAS) using antibody microarray-based oncoproteomics

    Science.gov (United States)

    Puig-Costa, Manuel; Codina-Cazador, Antonio; Cortés-Pastoret, Elisabet; Oliveras-Ferraros, Cristina; Cufí, Sílvia; Flaquer, Sílvia; Llopis-Puigmarti, Francesca; Pujol-Amado, Eulalia; Corominas-Faja, Bruna; Cuyàs, Elisabet; Ortiz, Rosa; Lopez-Bonet, Eugeni; Queralt, Bernardo; Guardeño, Raquel; Martin-Castillo, Begoña; Roig, Josep; Joven, Jorge; Menendez, Javier A.

    2014-01-01

    This study aimed to improve gastric cancer (GC) diagnosis by identifying and validating an INflammatory PROtein-driven GAstric cancer Signature (hereafter INPROGAS) using low-cost affinity proteomics. The detection of 120 cytokines, 43 angiogenic factors, 41 growth factors, 40 inflammatory factors and 10 metalloproteinases was performed using commercially available human antibody microarray-based arrays. We identified 21 inflammation-related proteins (INPROGAS) with significant differences in expression between GC tissues and normal gastric mucosa in a discovery cohort of matched pairs (n=10) of tumor/normal gastric tissues. Ingenuity pathway analysis confirmed the “inflammatory response”, “cellular movement” and “immune cell trafficking” as the most overrepresented biofunctions within INPROGAS. Using an expanded independent validation cohort (n = 22), INPROGAS classified gastric samples as “GC” or “non-GC” with a sensitivity of 82% (95% CI 59-94) and a specificity of 73% (95% CI 49-89). The positive predictive value and negative predictive value in this validation cohort were 75% (95% CI 53-90) and 80% (95% CI 56-94), respectively. The positive predictive value and negative predictive value in this validation cohort were 75% (95% CI 53-90) and 80% (95% CI 56-94), respectively. Antibody microarray analyses of the GC-associated inflammatory proteome identified a 21-protein INPROGAS that accurately discriminated GC from noncancerous gastric mucosa. PMID:24722433

  6. Studies on Purification of Methamidophos Monoclonal Antibodies and Comoarative Immunoactivity of Purified Antibodies

    Institute of Scientific and Technical Information of China (English)

    SU-QING ZHAO; YUAN-MING SUN; CHUN-YAN ZHANG; XIAO-YU HUANG; HOU-RUI ZHANG; ZHEN-YU ZHU

    2003-01-01

    Objective To purify Methamidophos (Met) monoclonal antibodies with two methods andcompare immune activity of purified antibodies. Method Caprylic acid ammonium sulphateprecipition (CAASP) method and Sepharose protein-A (SPA) affinity chromatography method wereused to purify Met monoclonal antibodies, UV spectrum scanning was used to determine proteincontent and recovery of purified antibodies, sodium dodecylsulphate polyacrylamide gelelectrophoresis (SDS-PAGE) was used to analyze the purity of purified antibodies, and enzyme-linkedimmunosorbent assay (ELISA) was used to determine immune activity of purified antibodies.Results Antibody protein content and recovery rate with CAASP method were 7.62 mg/mL and8.05% respectively, antibody protein content and recovery rate with SPA method were 6.45 mg/mLand 5.52% respectively. Purity of antibodies purified by SPA method was higher than that by CAASPmethod. The half-maximal inhibition concentration (IC50) of antibodies purified by SPA to Met was181.26 μg/mL, and the linear working range and the limit of quantification (LOD) were 2.43-3896.01μg/mL and 1.03 μg/mL, respectively. The IC50 of antibodies purified by CAASP to Met was 352.82μg/mL, and the linear working range and LOD were 10.91-11412.29 ug/mL and 3.42 μg/mL,respectively. Conclusion Antibodies purified by SPA method are better than those by CAASPmethod, and Met monoclonal antibodies purified by SPA method can be used to prepare gold-labelledtesting paper for analyzing Met residue in vegetable and drink water.

  7. Comprehensive analysis of varicella-zoster virus proteins using a new monoclonal antibody collection

    NARCIS (Netherlands)

    T.L. Roviš (Tihana Lenac); S.M. Bailer (Susanne); V.R. Pothineni (Venkata R); W.J.D. Ouwendijk (Werner ); H. Šimić (Hrvoje); M. Babić (Marina); K. Miklić (Karmela); S. Malić (Suzana); M.C. Verweij; M. Baiker (Martin); O. Gonzalez (Orland); A. Brunn (Albrecht von); R. Zimmer; K. Früh (Klaus); G.M.G.M. Verjans (George); S. Jonjic (Stipan); J. Haasb (Jürgeni)

    2013-01-01

    textabstractVaricella-zoster virus (VZV) is the etiological agent of chickenpox and shingles. Due to the virus's restricted host and cell typetropism and the lack of tools for VZV proteomics, it is one of the least-characterized human herpesviruses. We generated 251monoclonal antibodies (MAbs) again

  8. Acid-base chemistry of frustrated water at protein interfaces.

    Science.gov (United States)

    Fernández, Ariel

    2016-01-01

    Water molecules at a protein interface are often frustrated in hydrogen-bonding opportunities due to subnanoscale confinement. As shown, this condition makes them behave as a general base that may titrate side-chain ammonium and guanidinium cations. Frustration-based chemistry is captured by a quantum mechanical treatment of proton transference and shown to remove same-charge uncompensated anticontacts at the interface found in the crystallographic record and in other spectroscopic information on the aqueous interface. Such observations are untenable within classical arguments, as hydronium is a stronger acid than ammonium or guanidinium. Frustration enables a directed Grotthuss mechanism for proton transference stabilizing same-charge anticontacts.

  9. Non-standard amino acid incorporation into proteins using Escherichia coli cell-free protein synthesis

    Directory of Open Access Journals (Sweden)

    Seok Hoon eHong

    2014-06-01

    Full Text Available Incorporating non-standard amino acids (NSAAs into proteins enables new chemical properties, new structures, and new functions. In recent years, improvements in cell-free protein synthesis (CFPS systems have opened the way to accurate and efficient incorporation of NSAAs into proteins. The driving force behind this development has been three-fold. First, a technical renaissance has enabled high-yielding (>1 g/L and long-lasting (>10 h in batch operation CFPS in systems derived from Escherichia coli. Second, the efficiency of orthogonal translation systems has improved. Third, the open nature of the CFPS platform has brought about an unprecedented level of control and freedom of design. Here, we review recent developments in CFPS platforms designed to precisely incorporate NSAAs. In the coming years, we anticipate that CFPS systems will impact efforts to elucidate structure/function relationships of proteins and to make biomaterials and sequence-defined biopolymers for medical and industrial applications.

  10. Non-standard amino acid incorporation into proteins using Escherichia coli cell-free protein synthesis

    Science.gov (United States)

    Hong, Seok Hoon; Kwon, Yong-Chan; Jewett, Michael

    2014-06-01

    Incorporating non-standard amino acids (NSAAs) into proteins enables new chemical properties, new structures, and new functions. In recent years, improvements in cell-free protein synthesis (CFPS) systems have opened the way to accurate and efficient incorporation of NSAAs into proteins. The driving force behind this development has been three-fold. First, a technical renaissance has enabled high-yielding (>1 g/L) and long-lasting (>10 h in batch operation) CFPS in systems derived from Escherichia coli. Second, the efficiency of orthogonal translation systems has improved. Third, the open nature of the CFPS platform has brought about an unprecedented level of control and freedom of design. Here, we review recent developments in CFPS platforms designed to precisely incorporate NSAAs. In the coming years, we anticipate that CFPS systems will impact efforts to elucidate structure/function relationships of proteins and to make biomaterials and sequence-defined biopolymers for medical and industrial applications.

  11. [Diagnostic and prognostic significance of the antibodies to the myelin basic protein in acute neuroinfections in children].

    Science.gov (United States)

    Petrukhin, A S; Idrisova, Zh R; Vorov'eva, N L; Gervazieva, V B; Dekonenko, E P

    2001-01-01

    The development of severe CNS damages including encephalitis is highly probable in some respiratory and exanthemata viral infections (measles, rubella, parotitis). A high level of IgG antibodies to the myelin basic protein was found in patients with parotitis meningitis and rubella encephalitis but it was not high in 80% of patients with encephalitis of the unclear etiology and in 25% of cases with rubella encephalitis. More accurate analysis of clinical, neurovisual and immunologic data revealed a link of appearance of such complications with both the presence of more pronounced demyelinization and prolongation of the disease.

  12. Characterization of the antibody response against EV71 capsid proteins in Chinese individuals by NEIBM-ELISA

    OpenAIRE

    Ding, Yingying; Chen, Xuguang; Qian, Baohua; Wu, Guorong; He, Ting; Feng, Jiaojiao; Gao, Caixia; Wang, Lili; Wang, Jinhong; Li, Xiangyu; Cao, Mingmei; Peng, Heng; Zhao, Chunyan; Pan, Wei

    2015-01-01

    Human enterovirus 71 (EV71) has become the major pathogen of hand, foot, and mouth disease (HFMD) worldwide, while the anti-EV71 antibody responses other than neutralizing epitopes have not been characterized. In this study, EV71 capsid proteins VP1, VP3, VP0 and various VP1 antigens were constructed to analyze anti-EV71 response in severe HFMD cases, non-HFMD outpatient children and normal adults using a novel evolved immunoglobulin-binding molecule (NEIBM)-based ELISA. The high prevalence o...

  13. Chlamydia trachomatis and chlamydial heat shock protein 60-specific antibody and cell-mediated responses predict tubal factor infertility

    DEFF Research Database (Denmark)

    Tiitinen, A.; Surcel, H.-M.; Halttunen, M.;

    2006-01-01

    BACKGROUND: To evaluate the role of Chlamydia trachomatis-induced humoral and cell-mediated immune (CMI) responses in predicting tubal factor infertility (TFI). METHODS: Blood samples were taken from 88 women with TFI and 163 control women. C. trachomatis and chlamydial heat shock protein 60 (CHSP......60)-specific immunoglobulin G (IgG) antibodies were analysed using enzyme-linked immunosorbent assay (ELISA) kits. Proliferative reactivity of peripheral blood mononuclear cells was studied in vitro against Chlamydia elementary body (EB) and recombinant CHSP60 antigens. RESULTS: C. trachomatis-specific...

  14. Monoclonal antibody-assisted structure-function analysis of the carbohydrate recognition domain of surfactant protein D

    DEFF Research Database (Denmark)

    Hartshorn, Kevan L; White, Mitchell R; Rynkiewicz, Michael;

    2010-01-01

    Surfactant protein D (SP-D) plays important roles in host defense against a variety of pathogens including influenza A virus (IAV). Ligand binding by SP-D is mediated by the trimeric neck and carbohydrate recognition domain (NCRD). We used monoclonal antibodies (mAbs) against human SP-D and a panel......, for the first time, an extended binding site for IAV; calcium-dependent antiviral activity involves residues flanking the primary carbohydrate binding site as well as more remote residues displayed on the carbohydrate recognition domain surface....

  15. Periodic usage of low-protein methionine-fortified diets in broiler chickens under high ambient temperature conditions: effects on performance, slaughter traits, leukocyte profiles and antibody response

    Science.gov (United States)

    Ghasemi, Hossein Ali; Ghasemi, Rohollah; Torki, Mehran

    2014-09-01

    This study was performed to evaluate the effects of adding methionine supplements to low-protein diets and subsequent re-feeding with a normal diet on the productive performance, slaughter parameters, leukocyte profiles and antibody response in broiler chickens reared under heat stress conditions. During the whole exp