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Liu R, Wang C, Jiang Q, Zhang W, Yue Z, Liu G. Magnetic-particle-based, ultrasensitive chemiluminescence enzyme immunoassay for free prostate-specific antigen. Anal Chim Acta 2013; 801:91-6. [DOI: 10.1016/j.aca.2013.09.050] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 07/20/2013] [Accepted: 09/23/2013] [Indexed: 10/26/2022]
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2
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Lochner H, Strijdom B, Kishinevsky B, Steyn P. Limitations of the enzyme-linked immunosorbent assay for routine determination of legume inoculant quality. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1365-2672.1988.tb03377.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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3
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Affiliation(s)
- J E Butler
- University of Iowa Medical School, Iowa City, USA
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4
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L'Haridon RM. Immunosorbent binding bioassay: a solid phase biological immunoassay for the titration of antisera to alpha interferons. JOURNAL OF IMMUNOASSAY 1991; 12:99-112. [PMID: 2040713 DOI: 10.1080/01971529108055059] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
An Immuno Sorbent Binding Bio-Assay (ISBBA) for the detection and the titration of antisera to the highly biologically active proteins, alpha interferons, is described. This method is similar to a classical solid phase immunoassay, except for the last step which uses the biological activity of the captured antigen. With specific serum antibodies the bound antigen prevents further virus induced cell lysis. On the contrary, with negative serum or preserum the antigen is washed out and virus induced cell lysis occurs, therefore no labelling is required. ISBBA exhibits three main differences when compared to the reference method i.e. the neutralization assay (NA): i) ISBBA is 10 to 1000 fold more sensitive than NA; ii) in contrast to NA, ISBBA is based on the production of an antiviral effect; iii) ISBBA makes it possible to use unpurified antigen. The applications of ISBBA to subtypes study in natural alpha interferon samples are discussed.
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Affiliation(s)
- R M L'Haridon
- Laboratoire de Virologie et Immunologie Moléculaires, INRA, Domaine de Vilvert, Jouy en Josas, France
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5
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Ramanathan VD, Parkash O, Tyagi P, Sengupta U, Ramu G. Activation of the human complement system by phenolic glycolipid 1 of Mycobacterium leprae. Microb Pathog 1990; 8:403-10. [PMID: 2266854 DOI: 10.1016/0882-4010(90)90027-n] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The activation of the complement system by phenolic glycolipid 1 (PGL) from Mycobacterium leprae was studied. It was found that PGL consumed haemolytic complement through both the classical and the alternative pathways. This was further studied at the level of C3. Although the activation was independent of anti-PGL antibodies present in normal human serum, the addition of antibody augmented the activation of complement by PGL. The uptake of C3 through the classical pathway was enhanced predominantly by IgM antibody whereas, IgG antibody against PGL was responsible for the augmentation of the alternative pathway activation. Furthermore, it was found that both the disaccharide and trisaccharide components of PGL were able to activate the complement system.
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Affiliation(s)
- V D Ramanathan
- Department of Pathology, Tuberculosis Research Centre, Chetput, Madras, India
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7
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Wiersma EJ, Coulie PG, Heyman B. Dual immunoregulatory effects of monoclonal IgG-antibodies: suppression and enhancement of the antibody response. Scand J Immunol 1989; 29:439-48. [PMID: 2470138 DOI: 10.1111/j.1365-3083.1989.tb01143.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Nine monoclonal IgG-anti-TNP antibodies were investigated for their ability to modulate anticarrier responses in mice immunized with sheep red blood cells-2,4,6-trinitrophenyl (SRBC-TNP) or keyhole limpet haemocyanin-TNP (KLH-TNP). The antibodies enhanced the anticarrier response when KLH-TNP was used as antigen but suppressed it when SRBC-TNP was used. The enhancing and suppressive effects were not exerted by entirely the same sets of antibodies. The suppression was correlated to efficient antigen binding, but not complement activation, haemagglutination, or isotype of the monoclonal antibodies. In contrast, enhancement was correlated to isotype and complement activation but not to antigen binding capacity. Both the enhancing and the suppressive effects seem to require Fc-mediated functions of the IgG molecules since they modulate the anti-carrier response although they recognize hapten determinants. Thus, one and the same monoclonal hapten-specific IgG-antibody can enhance the anti-KLH response up to 38-fold whereas it suppresses the anti-SRBC response by more that 10-fold.
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Affiliation(s)
- E J Wiersma
- Department of Immunology, Uppsala University, Sweden
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8
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Savelkoul HF, Soeting PW, De Josselin De Jong JE, Pathak SS. Terasaki-ELISA for murine IgE antibodies. II. Quantitation of absolute concentration of antigen-specific and total IgE. J Immunol Methods 1989; 116:277-85. [PMID: 2492054 DOI: 10.1016/0022-1759(89)90214-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A Terasaki tray-based ELISA system was developed for the quantitative measurement of antigen-specific and total IgE antibodies in 5 microliter samples of mouse serum dilutions. The assay was based upon non-competitive binding of mouse IgE antibodies between the immobilized appropriate antigen or capture antibodies and the detecting rabbit antibodies. A conjugate of protein A-labelled beta-galactosidase and the fluorigenic substrate methylumbelliferyl-beta-D-galactoside were used as a detecting system. The resulted fluorescence could be measured rapidly and automatically using an inverted micro-fluorimeter. These measurements were automatically transformed into absolute concentrations by a microprocessor-based program using a four-parameter logistic function and an absolute IgE standard. The assay was shown to have a detection limit of 0.04 ng/ml and a range of linearity of 0.04-20 ng/ml, which is sufficient to measure IgE concentrations in mouse serum.
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Affiliation(s)
- H F Savelkoul
- Department of Cell Biology, Immunology and Genetics, Erasmus University, Rotterdam, The Netherlands
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9
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Larsson A, Jonsson L, Sjöquist J. Determination of circulating immune complexes by chicken anti-human C3 and anti-human C1q microELISA. J Immunol Methods 1988; 113:93-9. [PMID: 3262687 DOI: 10.1016/0022-1759(88)90385-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The present study reports on an anti-human C1q and an anti-human C3 microELISA for measuring circulating immune complexes (CIC). Affinity-purified chicken anti-human C3 and anti-human C1q were used as capture antibodies and protein A-alkaline phosphatase conjugate for detection. Chicken antibodies do not activate mammalian complement, do not react with rheumatoid factor and are not bound to anti-mammalian IgG antibodies or protein A, which often are used for detection in ELISA. They are therefore suitable as capture antibodies in CIC assays. We have tested Bell's palsy patients and found an increase in both anti-C3- and anti-C1q-containing CIC in acute and convalescent sera compared with the normal.
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Affiliation(s)
- A Larsson
- Department of Medical and Physiological Chemistry, Biomedical Centre, Uppsala, Sweden
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10
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Parkash O, Ramanathan V, Singh D, Sengupta U. Effect of anti-mycobacterial antibodies on activation of the alternative pathway of the human complement system. FEMS Microbiol Lett 1988. [DOI: 10.1111/j.1574-6968.1988.tb02810.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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11
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Rönnstrand L, Terracio L, Claesson-Welsh L, Heldin CH, Rubin K. Characterization of two monoclonal antibodies reactive with the external domain of the platelet-derived growth factor receptor. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(19)81534-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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12
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Martindale JJ, Ganzinger U, Steinmüller W, Millendorfer A, Ambrosch F, Kollaritsch H, Wiedermann G. Tolerability and immunogenicity of a polyvalent Pseudomonas aeruginosa extract vaccine in human volunteers. ZENTRALBLATT FUR BAKTERIOLOGIE, MIKROBIOLOGIE, UND HYGIENE. SERIES A, MEDICAL MICROBIOLOGY, INFECTIOUS DISEASES, VIROLOGY, PARASITOLOGY 1988; 268:376-85. [PMID: 3136608 DOI: 10.1016/s0176-6724(88)80023-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A polyvalent 16 serotype Pseudomonas extract vaccine was administered to normal volunteers to ascertain tolerability, immunogenicity and immunisation schedule. Four groups of nine volunteers were immunised with 0.8 X 10(9) bacterial equivalents (BE), 1.2 X 10(9) BE, 1.6 X 10(9) BE or placebo, respectively, on days 0, 14 and 21. A further six volunteers were immunised with 1.6 X 10(9) BE on days 0 and 28. Tolerability was excellent, slight side effects were unrelated to vaccine concentration and decreased with the number of injections. All concentrations of vaccine gave a significantly increased titre 14 days after the first immunisation. Reimmunisation did not increase the titre, which reached a plateau at day 14. Individuals with high pre-immunisation-titres produced very high post-immunisation-titres with a conversion factor of 6.5 whilst those with low pre-immunisation-titres had a higher conversion factor of 13 but produced lower final titres. ELISA titre did not always correlate with biological activity (mouse protection assay) suggesting that effective protective antibodies are only part of the total specific antibody measured by ELISA with the polyvalent whole-cell vaccine antigen.
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13
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Reis KJ, Von Mering GO, Karis MA, Faulmann EL, Lottenberg R, Boyle MD. Enzyme-labeled type III bacterial Fc receptors. A versatile tracer for immunoassay. J Immunol Methods 1988; 107:273-80. [PMID: 3279131 DOI: 10.1016/0022-1759(88)90228-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The type III bacterial Fc receptor isolated form a group C streptococcus has been conjugated to alkaline phosphatase and used as a tracer in a variety of direct and indirect immunoassays. These immunoassays have utilized specific antibodies prepared in species whose immunoglobulins are poorly reactive with the type I Fc receptor, staphylococcal protein A. The value of the type III Fc receptor as a tracer for immunoassays utilizing antibodies produced in sheep and goats is documented.
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Affiliation(s)
- K J Reis
- Department of Reproduction, University of Florida College of Veterinary Medicine, Gainesville
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15
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Nilson B, Björck L, Akerström B. Enzyme linked immunosorbent assay using alkaline phosphatase conjugated with streptococcal protein G. JOURNAL OF IMMUNOASSAY 1988; 9:207-25. [PMID: 3372703 DOI: 10.1080/15321818808057041] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Protein G, an IgG-binding protein, purified from the surface of group G streptococci, was coupled to alkaline phosphatase. The conjugate was used for detection of polyclonal goat and rabbit antibodies and monoclonal mouse IgG1, IgG2a and IgG2b in an enzyme-linked immunosorbent assay. A two-step coupling procedure was used, in which glutaraldehyde was allowed to react with the enzyme, excess glutaraldehyde was then removed by dialysis, and finally protein G added to the glutaraldehyde-activated and polymerized alkaline phosphatase. The activity and yield of the conjugates were then tested in an enzyme-linked immunosorbent assay. Coupling of 25 micrograms protein G to 5 mg alkaline phosphatase gave a conjugate which could be used for more than 10,000 determinations with maximal antibody binding giving an absorbance of 2.0. Under these conditions, there was no need for separation of the reactants before using the protein G-alkaline phosphatase complex.
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Affiliation(s)
- B Nilson
- Department of Physiological Chemistry, University of Lund, Sweden
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16
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Ball WJ. Uncoupling of ATP binding to Na+,K+-ATPase from its stimulation of ouabain binding: studies of the inhibition of Na+,K+-ATPase by a monoclonal antibody. Biochemistry 1986; 25:7155-62. [PMID: 3026448 DOI: 10.1021/bi00370a058] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The effects of a monoclonal antibody, prepared against the purified lamb kidney Na+,K+-ATPase, on the enzyme's Na+,K+-dependent ATPase activity were analyzed. This antibody, designated M10-P5-C11, is directed against the catalytic subunit of the "native" holoenzyme. It inhibits greater than 90% of the ATPase activity and acts as a noncompetitive or mixed inhibitor with respect to the ATP, Na+, and K+ dependence of enzyme activity. It inhibits the Na+- and Mg2+ATP-dependent phosphoenzyme intermediate formation. In contrast, it has no effect on K+-dependent p-nitrophenylphosphatase (pNPPase) activity, the interconversion of the phosphoenzyme intermediates, and ADP-sensitive or K+-dependent dephosphorylation. It does not alter ATP binding to the enzyme nor the covalent labeling of the enzyme at the presumed ATP site by fluorescein 5'-isothiocyanate (FITC), but it prevents the ATP-induced stimulation in the rate of cardiac glycoside [3H]ouabain binding to the Na+,K+-ATPase. M10-P5-C11 binding appears to inhibit enzyme function by blocking the transfer of the gamma-phosphoryl of ATP to the phosphorylation site after ATP binding to the enzyme has occurred. In the presence of Mg2+ATP, it also prevents the ATP-induced transmembrane conformational change that enhances cardiac glycoside binding. This uncoupling of ATP binding from its stimulation of ouabain binding and enzyme phosphorylation demonstrates the existence of an enzyme-Mg2+ATP transitional intermediate preceding the formation of the Na+-dependent ADP-sensitive phosphoenzyme intermediate. These results are also consistent with a model of the Na+,K+-ATPase active site being composed of two distinct but interacting regions, the ATP binding site and the phosphorylation site.
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17
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Ayanaba A, Weiland KD, Zablotowicz RM. Evaluation of Diverse Antisera, Conjugates, and Support Media for Detecting
Bradyrhizobium japonicum
by Indirect Enzyme-Linked Immunosorbent Assay. Appl Environ Microbiol 1986; 52:1132-8. [PMID: 16347212 PMCID: PMC239186 DOI: 10.1128/aem.52.5.1132-1138.1986] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We evaluated three antisera and four enzyme conjugates for the detection of
Bradyrhizobium japonicum
by an indirect enzyme-linked immunosorbent assay in microtiter plates. Nitrocellulose membrane sheets were then evaluated as an alternative support medium by using some combinations. Partially purified immunoglobulin G (IgG) or unpurified antisera to strain USDA 110 raised in rabbits, goats, or sheep was reacted in microtiter plates with alkaline phosphatase conjugated to protein A, goat anti-rabbit (GAR), sheep anti-rabbit (SAR), or rabbit anti-goat (RAG) IgG. Cultures or nodules containing homologous rhizobia were detected with equal sensitivity when protein A, GAR, or SAR was reacted with 5 μg of protein IgG per ml or a 1:800 titer of antisera from rabbits, but not goats or sheep. RAG reacted with IgG or antisera from goats or sheep. The detection limit was 2 × 10
5
rhizobia per well. Rhizobia were spotted on nitrocellulose sheets as an alternative support medium, followed by soaking in 5 μg of protein per ml as IgG and 1:4,000 dilutions of protein A or GAR conjugate. Rhizobia in serogroup 110 were detected with the dye combination Nitro Blue Tetrazolium-5-bromo-4-chloro-3-indolyl phosphate (NBT-BCIP), and rhizobia in serogroup 122 were detected with fast red-naphthol phosphate (FR-NP). At the conclusion of the 5-h assay, purple (NBT-BCIP) or red (FR-NP) spots were visible in positive reactions. The sensitivity of detection was about 1,000 rhizobial cells or 3 μg of nodules tissue.
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Affiliation(s)
- A Ayanaba
- Crop Science Laboratory, Syracuse Research Laboratory, Allied-Signal Inc., Solvay, New York 13209
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18
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Ball WJ, Lane LK. Immunochemical comparison of cardiac glycoside-sensitive (lamb) and -insensitive (rat) kidney (Na+ + K+)-ATPase. BIOCHIMICA ET BIOPHYSICA ACTA 1986; 873:79-87. [PMID: 2427119 DOI: 10.1016/0167-4838(86)90192-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The immunological cross-reactivity of the ouabain-sensitive lamb kidney and the ouabain-insensitive rat kidney (Na+ + K+)-ATPase (EC 3.6.1.37) was examined using polyclonal and monoclonal antibodies. Studies using rabbit antisera prepared against both the lamb kidney and rat kidney holoenzymes showed the existence of substantial antigenic differences as well as similarities between the holoenzymes and the respective denatured alpha and beta subunits of these two enzymes. Quantitation of the extent of cross-reactivity using holoenzyme-directed antibodies showed a 40-60% cross-reactivity. In addition, rabbit antisera monospecific to the purified, denatured alpha and beta subunits of the lamb kidney enzyme showed about a 50% cross-reactivity towards the respective subunit of the rat enzyme. In contrast to the cross-reactivity observed using the polyclonal antibodies, six monoclonal antibodies specific for the alpha subunit of the lamb holoenzyme exhibited no cross-reactivity with the rat holoenzyme. Four of these monoclonal antibodies, however, showed substantial cross-reactivity with rat alpha subunit as resolved by SDS-polyacrylamide gel electrophoresis. A fifth antibody did not bind to the denatured alpha subunit of either the lamb or the rat enzyme. Another monoclonal antibody (M7-PB-E9), which is specific for an epitope previously implicated in the regulation of both ATP and ouabain binding to (Na+ + K+)-ATPase (Ball, W.J., Jr. (1984) Biochemistry 2275-2281) was found to bind to the denatured lamb alpha but not to the rat alpha. This antibody has identified a region of the lamb alpha that has an altered amino acid sequence in the ouabain-insensitive rat enzyme. These immunological studies indicate that there are substantial antigenic differences between the lamb and rat kidney (Na+ + K+)-ATPases. The majority of these antigenic differences appear to be due to variations in the tertiary structures rather than to variations in the primary structures of the alpha subunits.
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19
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Holmdahl R, Nordling C, Rubin K, Tarkowski A, Klareskog L. Generation of monoclonal rheumatoid factors after immunization with collagen II-anti-collagen II immune complexes. An anti-idiotypic antibody to anti-collagen II is also a rheumatoid factor. Scand J Immunol 1986; 24:197-203. [PMID: 3489283 DOI: 10.1111/j.1365-3083.1986.tb02086.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Two monoclonal IgG rheumatoid factors were obtained after hybridization of spleen cells from DBA/1 mice immunized with immune complexes containing native collagen type II and a monoclonal anti-collagen II antibody. One of these rheumatoid factors reacted not only with purified murine Fc fragments, but also with Fab fragments of the anti-collagen II antibody used for immunization, whereas no reactivity was seen with Fab fragments from normal mouse IgG. The findings demonstrate the ability of immune complexes encompassing native collagen type II to induce production of IgG rheumatoid factors, and suggest that an idiotypic relationship may exist between certain rheumatoid factors and anti-collagen II antibodies.
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20
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Thomas DG, Linton HJ, Garvey JS. Fluorometric ELISA for the detection and quantitation of metallothionein. J Immunol Methods 1986; 89:239-47. [PMID: 3701075 DOI: 10.1016/0022-1759(86)90364-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The development of a heterogeneous fluorometric ELISA for the detection and quantitation of metallothionein (MT) is described. A radioimmunoassay (RIA) previously developed in our laboratory is used as a reference assay to characterize the performance of the ELISA. The standard curves (logit-log regressions) that are typical of either assay have similar ranges (customarily from 20 000 to 100 pg of competing antigen); both assays are capable of quantitating MT in unknowns with 5-10% accuracy. Aspects of MT measurement in cytosols and physiological fluids are discussed.
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21
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Pontes-de-Carvalho LC, Lannes-Vieira J, Giovanni-de-Simone S, Galvão-Castro B. A protein A-binding, polyethylene glycol precipitation-based immunoradiometric assay. Application to the detection of immune complexes and C3 in human sera and of private antigens in cross-reacting parasite extracts. J Immunol Methods 1986; 89:27-35. [PMID: 3517172 DOI: 10.1016/0022-1759(86)90028-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
An immunoradiometric assay, based on the precipitation of antigen-antibody complexes by polyethylene glycol (PEG) and on the subsequent binding of PEG-soluble radiolabelled staphylococcal protein A to the PEG-insoluble complexes, is described. The assay can be applied to the detection of naturally occurring, circulating immune complexes, and of complexes artificially created by mixing antigen and antibody solutions, which makes it of potential use for the detection of either antigen or antibody in several situations. Pre-treatment of the antibody-containing sera with 3% PEG greatly reduced the background values and increased the sensitivity of the assay. The assay was also applied to the detection and isolation of Leishmania donovani antigens that did not cross-react with antigens of the related parasite Trypanosoma cruzi (private antigens) and private antigens of insect-derived metacyclic trypomastigotes of T. cruzi in relation to culture-derived metacyclic trypomastigotes of T. cruzi. A simple and extremely effective procedure for washing precipitates with just one centrifugation is also described.
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22
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Holmdahl R, Rubin K, Klareskog L, Larsson E, Wigzell H. Characterization of the antibody response in mice with type II collagen-induced arthritis, using monoclonal anti-type II collagen antibodies. ARTHRITIS AND RHEUMATISM 1986; 29:400-10. [PMID: 2421741 DOI: 10.1002/art.1780290314] [Citation(s) in RCA: 303] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Twenty monoclonal antibodies reactive with type II collagen were characterized as to their determinant specificity and their reactivity with cartilage-derived components. The monoclonal antibodies reacted with 7 different epitopes on the native type II collagen triple helical structure. Antibodies defining 3 of these epitopes occurred more frequently in sera from arthritic mice than in sera from nonarthritic mice. In vivo injection of some selected autoreactive antibodies caused synovitis, but in no case did it give rise to full-blown arthritis.
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23
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Holmdahl R, Jansson L, Larsson E, Rubin K, Klareskog L. Homologous type II collagen induces chronic and progressive arthritis in mice. ARTHRITIS AND RHEUMATISM 1986; 29:106-13. [PMID: 3947407 DOI: 10.1002/art.1780290114] [Citation(s) in RCA: 141] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Native mouse type II collagen was used for immunization of DBA/1 mice. Arthritis developed exclusively in male animals and was characterized by a variable and delayed onset, a slow and progressive development, and frequent exacerbations of disease in several joints including those that were previously affected. Titers of anti-type II collagen autoantibodies were found not to correlate well with arthritis development. It appears that experimental arthritis induced with homologous type II collagen resembles rheumatoid arthritis in humans, both in certain clinical features and in the lack of correspondence between anti-type II collagen autoantibody titers and disease symptoms.
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24
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Ronald P, Söderhäll K. PHENYLALANINE AMMONIA LYASE AND PEROXIDASE ACTIVITY IN MYCORRHIZAL AND NONMYCORRHIZAL SHORT ROOTS OF SCOTS PINE, PINUS SYLVESTRIS L. THE NEW PHYTOLOGIST 1985; 101:487-494. [PMID: 33874232 DOI: 10.1111/j.1469-8137.1985.tb02854.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Phenylalanine ammonia lyase was characterized in roots of Pinus sylvestris L. The Km for the pine root enzyme with phenylalanine as a substrate was l.2 ± 0.4 X 10-4 M. The enzyme had a pH activity optimum of 9 and the subunit molecular weight was 70 to 72 kD as determined by Western blotting. Enzyme activity could be inhibited by D,L-2-aminooxy 3 phenylpropionic acid at 1 μ. Treatments with zymosan, pectinase, light or kinetin and naphthylacetic acid did not induce higher phenylalanine ammonia lyase or peroxidase activity in pine roots. No significant differences were observed in phenylalanine ammonia lyase or peroxidase activity in mycorrhizal and nonmycorrhizal short roots in the P. sylvestris-L. laccata symbiosis 15 weeks after cultivation.
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Affiliation(s)
- Pamela Ronald
- Institute of Physiological Botany, University of Uppsala, Box 540, S-751 21 Uppsala, Sweden
| | - Kenneth Söderhäll
- Institute of Physiological Botany, University of Uppsala, Box 540, S-751 21 Uppsala, Sweden
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25
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Katz D, Lehrer S, Kohn A. Use of chicken and rabbit antibodies in a solid phase protein A radioimmunossay for virus detection. J Virol Methods 1985; 12:59-70. [PMID: 4077951 DOI: 10.1016/0166-0934(85)90008-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A new rapid indirect solid phase radioimmunoassay was developed for the detection of Sindbis virus. Chicken antibodies were adsorbed onto wells in microplates to serve as 'capture antibodies' and rabbit antibodies were used as the second antibody. 125I-labelled protein A that does not bind to chicken antibodies, but binds firmly to rabbit antibodies was used as the tracer. All the steps necessary for the development of the assay are described. The minimal amount of Sindbis virus detectable was around 3 x 10(5) PFU/ml and the interassay reproducibility was about +/- 30%.
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Abstract
Aldose reductase, aldehyde reductase and carbonyl reductase constitute a family of monomeric NADPH-dependent oxidoreductases with similar physical and chemical properties. Characterization of the enzymes from human tissues by immunotitration and an enzyme immunoassay indicated that, despite their apparent likeness, the three reductases do not cross-react immunochemically.
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Abstract
A novel form of indirect enzyme-linked immunosorbent assay (ELISA) has been devised for the detection of viruses in plants. The method uses protein A in two applications to sandwich antibody-antigen-antibody layers. The first applied layer of protein A prepares the plate for the coating antibody layer. The second layer of protein A is conjugated to the enzyme and detects the second antibody layer. The orientation of the IgG induced in the coating layer of antibody prevents later unwanted reaction with the conjugated protein A. Using seven antisera, protein A sandwich ELISA (PAS-ELISA) detected homologous virus isolates in standard dilutions of infected plant homogenates at A405 values which were at least one absorbance unit greater than those of healthy controls. The PAS-ELISA method was more sensitive than the direct double antibody sandwich form of ELISA (DAS-ELISA), e.g. not only were A405 values for homologous reactions greater in PAS-ELISA but also an antiserum to a birch isolate of cherry leaf roll virus detected four related isolates with the new method against only one with DAS-ELISA. However, dilution end points for the homologous virus were about the same in both methods. In a practical application, PAS-ELISA detected prune dwarf virus in 18-36% of tested Prunus avium seeds.
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Radojcic M, Okret S, Wrange O, Gustafsson JA. Characterization of non-liganded glucocorticoid receptor in rat liver cytosol using indirect competitive enzyme-linked immunosorbent assay. JOURNAL OF STEROID BIOCHEMISTRY 1985; 23:1-8. [PMID: 4021489 DOI: 10.1016/0022-4731(85)90253-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
We have previously shown that the purified or unfractionated cytosolic, activated glucocorticoid receptor of rat liver consists of a polypeptide with a Stokes radius of approximately 6 nm, a sedimentation coefficient of 4S and a molecular mass of approximately 90,000 Daltons. We have confirmed previous observations by other authors that if sodium molybdate is introduced into the cytosol preparation buffer the non-activated glucocorticoid receptor appears as an 8 nm, 9S species with an apparent molecular mass of 330,000 Daltons. In order to study the physicochemical parameters of the glucocorticoid receptor prior to ligand binding, we have used an enzyme-linked immunosorbent assay (ELISA) based on antibodies raised in rabbits against the purified activated glucocorticoid receptor. In isotonic buffer, the non-liganded glucocorticoid receptor was shown to have a Stokes radius of 6 nm in the absence and 8 nm in the presence of molybdate. Furthermore, experimental conditions known to result in activation of the glucocorticoid receptor complex (increased ionic strength, increased temperature) did not lead to activation of the 6 nm non-liganded glucocorticoid receptor as judged from the lack of binding of the treated, non-liganded receptor to DNA-cellulose. The existence of both 6 and 8 nm forms of nonactivated, non-liganded glucocorticoid receptor in vitro suggests that dissociation of an 8 nm form to a 6 nm form, if it occurs in vivo, is probably not the only molecular event constituting the activation of the glucocorticoid receptor.
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Toivonen ML, Lindén IB, Gripenberg M, Vapaatalo H. The usability of the MRL/1 mouse strain in detection of anti-rheumatic drugs. AGENTS AND ACTIONS 1984; 15:578-83. [PMID: 6532180 DOI: 10.1007/bf01966777] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
D-Penicillamine (5 mg/kg), prednisolone (0.5 mg/kg), tolfenamic acid and thiabendazole (10 mg/kg) were chronically administered to male and female mice of MRL/1 strain. The treatment was started either at 4 weeks of age (prophylactic dosing) or at 12 weeks of age (therapeutic dosing) and continued until the termination at 24 weeks of age. In male mice all the drugs caused a significant retardation in IgM-RF formation with one of the dosing regimes. D-Penicillamine and prednisolone also had an inhibitory effect on lymph node enlargement. In female mice, however, only thiabendazole retarded the RF activity significantly. None of the drugs had any marked effect on anti-ssDNA antibody formation, and none of the treatments affected the development of renal disease or modified the survival of these mice.
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Shoham J, Cohen M, Wallach D. An immunoenzyme quantitative assay for the antiviral effect of interferons. J Immunol Methods 1984; 72:279-87. [PMID: 6205098 DOI: 10.1016/0022-1759(84)90456-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A technique is described for measurement of the antiviral activity of interferon by an immunoenzymatic assay for viral proteins. Cells treated by tested samples of interferon (IFN) are infected with vesicular stomatitis virus (VSV) and following the development of viral cytopathy are lysed by the addition of deoxycholate and then transferred into ELISA microplates. The viral proteins bind effectively to the microplates proportionally to their level in the culture and may be measured by incubating the plates sequentially with (1) rabbit antiserum against VSV, (2) a conjugate of alkaline phosphatase either to protein A or to an antibody against rabbit IgG and (3) p-nitrophenylphosphate. This procedure may be further simplified by using antibodies against VSV to which alkaline phosphatase has been directly conjugated. We found this immunoenzyme assay to be superior to the 'cytopathic effect inhibition' assay in precision and sensitivity and in being independent of the effectiveness of viral cytopathy.
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Baumgartner A, Nicolet J. Detection of antibodies against membrane-glycoproteins of swine erythrocytes after experimental infection with Mycoplasma hyopneumoniae. Vet Immunol Immunopathol 1984; 7:73-9. [PMID: 6485250 DOI: 10.1016/0165-2427(84)90029-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
During enzootic pneumonia of pig, antibodies against membrane glycoproteins of erythrocytes were detected with an enzyme-linked immunosorbent assay (ELISA). These antibodies arise simultaneously with the specific antibodies. They are not identical to cold agglutinins.
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32
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Nachman RL, Leung LL, Kloczewiak M, Hawiger J. Complex formation of platelet membrane glycoproteins IIb and IIIa with the fibrinogen D domain. J Biol Chem 1984. [DOI: 10.1016/s0021-9258(17)39770-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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33
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Heyman B, Holmquist G, Borwell P, Heyman U. An enzyme-linked immunosorbent assay for measuring anti-sheep erythrocyte antibodies. J Immunol Methods 1984; 68:193-204. [PMID: 6368693 DOI: 10.1016/0022-1759(84)90150-9] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A simple ELISA assay for detecting murine anti-SRBC antibodies of IgG class was developed and the variation of the results according to different experimental conditions was investigated. Erythrocytes were left to settle in flexible plastic microtiter plates, after which they were fixed with glutaraldehyde and the remaining binding sites in the plates saturated with ovalbumin. Serum or monoclonal IgG antibodies were then allowed to react with the erythrocytes. Protein A coupled to alkaline phosphatase caused a color change in the subsequently added enzyme substrate. The results proved to be of good reproducibility, specificity and sensitivity. The assay can be used for measuring IgG concentration, estimating antibody avidity and number of antigenic determinants on the SRBC, as well as screening IgG anti-SRBC hybridomas. The precision of concentration estimates was very good when standard curves were used.
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Fey H, Pfister H, Rüegg O. Comparative evaluation of different enzyme-linked immunosorbent assay systems for the detection of staphylococcal enterotoxins A, B, C, and D. J Clin Microbiol 1984; 19:34-8. [PMID: 6361061 PMCID: PMC270973 DOI: 10.1128/jcm.19.1.34-38.1984] [Citation(s) in RCA: 102] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
We compared four versions of the enzyme-linked immunosorbent assay for their suitability for detecting staphylococcal enterotoxins. The sandwich with labeled antibody proved to be the best. We used it with a sorbent consisting of antibody-coated polystyrene spheres reacted with 20 ml of food extract. The sensitivity of the test was 0.1 ng of enterotoxin per ml, which is far below clinical relevance. The succinimidyl-pyridyl-dithio-propionate enzyme coupling method of Pharmacia was superior to the two-step glutaraldehyde technique. Interfering protein A was eliminated by the simple addition of normal rabbit serum to the extracts. A diagnostic kit is now available.
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Sternås L, Luka J, Kallin B, Rosén A, Henle W, Henle G, Klein G. Enzyme-linked immunosorbent assay for the detection of Epstein-Barr virus-induced antigens and antibodies. J Immunol Methods 1983; 63:171-85. [PMID: 6311908 DOI: 10.1016/0022-1759(83)90422-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Two Epstein-Barr virus (EBV)-specific ELISA tests were developed. One, based on the use of crude extracts from virus producer cells highly induced in the presence of Ara C (providing EA + VCA- cells) or in the absence of the drug (providing EA + VCA + cells) is suitable for the detection of antibodies directed against antigen complexes associated with the lytic virus cycle; i.e., EA, VCA and presumably also MA. The second, performed with purified EBNA, can be used for the detection of antibodies to the transformation-associated nuclear antigen. The tests are expected to find application in the dissection of antibody responses of patients to various antigenic subcomponents, the monitoring of EBV-coded antigens during biochemical purification, and the screening of spent media from hybridoma cultures for EBV-specific antibodies.
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Abstract
A modification of the ELISA assay is described which significantly enhances the chromogenic signal, thereby increasing the sensitivity of the assay. This enhanced ELISA employs a protein A-HRP conjugate to detect antibody bound to antigen coated polystyrene plates, followed by incubation with an anti-protein A-HRP conjugate as the amplification step. This enhanced ELISA is rapid, inexpensive, uses commercially available reagents and maintains the low background and high specificity of standard ELISA.
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Leptin M, Melchers F. A monoclonal antibody with specificity for murine mu heavy chain which inhibits the formation of antigen-specific direct IgM plaques. J Immunol Methods 1983; 59:53-61. [PMID: 6187865 DOI: 10.1016/0022-1759(83)90145-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A panel of monoclonal rat antibodies binding to mouse mu heavy chain were tested for their ability to inhibit the formation of antigen-specific plaques in the hemolytic plaque assay. Nine antibodies inhibited SRC-specific direct IgM plaques at high concentrations (greater than 20 micrograms/ml). In contrast to all others, however, one antibody inhibited these plaques at much lower concentrations (down to 0.4 microgram/ml) when added to the assay. This antibody also inhibited plaques formed by cells secreting antibodies against trinitrophenyl or phosphorylcholine determinants. IgG plaques with any of the above specificities were not inhibited. IgM secretion was unaffected by the monoclonal anti-mu antibody. Its inhibitory effect on plaque formation rather appears to be a consequence of its ability to inhibit complement dependent, IgM mediated lysis of erythrocytes. This monoclonal anti-IgM antibody therefore provides a convenient reagent to distinguish specific direct IgM plaques from indirect IgG plaques.
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Ball WJ, Collins JH, Lane LK, Schwartz A. Studies of the antigenic properties of the catalytic and glycoprotein subunits of Na+,K+-ATPase. Arch Biochem Biophys 1983; 221:371-80. [PMID: 6301373 DOI: 10.1016/0003-9861(83)90156-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Antibodies were raised against isolated, delipidated catalytic [alpha] and glycoprotein [beta] subunits of the Na+,K+-dependent ATPase purified from lamb kidney medulla. The specificity of each antiserum was confirmed by agar double-diffusion precipitation, immunoelectrophoresis, and polyacrylamide gel electrophoresis. A solid phase adsorption assay was also employed to determine antibody binding titers and to further test the specificity of these antisera. Antibodies raised to the alpha subunit had a strong reactivity and similar titer values for both the holoenzyme and the alpha subunit and a low-affinity cross-reactivity with the beta subunit. In contrast, beta-subunit-directed antibodies had little reactivity or binding with the holoenzyme and a low-affinity cross-reactivity with the alpha subunit. Competition binding studies revealed that about 80% of the alpha-subunit-specific antibodies bound to the holoenzyme, indicating that similar sets of antigenic sites are exposed in the lipid-embedded holoenzyme complex and in the isolated alpha subunit. Competition binding studies also suggest that the subunit cross-reactivities of the antisera may not result from simple contamination of the respective antigens, but that there may be partial homologies of some antigenic sites. In addition, the beta-directed antibodies had no effect on Na+,K+-ATPase activity, while the alpha-directed antibodies were effective inhibitors of activity. This indicates that at least some functionally important antigenic sites of the alpha subunit may be unaltered by its isolation and delipidation.
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Collins JH, Zot AS, Ball WJ, Lane LK, Schwartz A. Tryptic digest of the alpha subunit of lamb kidney (Na+ + K+)-ATPase. BIOCHIMICA ET BIOPHYSICA ACTA 1983; 742:358-65. [PMID: 6297590 DOI: 10.1016/0167-4838(83)90322-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The Mr approximately equal to 100 000 alpha subunit was prepared from highly purified lamb kidney (Na+ + K+)-ATPase. Its N-terminal sequence is Gly-Arg-Asx-Lys-Tyr-Glu. The alpha subunit was S-carboxymethylated, succinylated, and cleaved at its 40 arginine residues with trypsin. Four major, well-differentiated peptide fractions (A to D) were obtained by chromatography of the digest on a Sephadex G-50 column. Fraction A eluted at the void volume of the column and contained aggregated, very hydrophobic peptides, possibly from regions of alpha that are buried within the membrane lipid bilayer in the native enzyme. Fractions B to D, which together accounted for about 75% of the total protein, contained water-soluble peptides. To test the feasibility of using antibodies to identify and purify specific peptides of alpha subunit, studies were carried out using antibodies to native (Na+ + K+)-ATPase. Carboxymethylation and succinylation did not significantly decrease total antibody binding to alpha subunit, although the affinity of the anti-(Na+ + K+)-ATPase antibodies for alpha subunit was reduced by about 50%. The tryptic peptides of alpha subunit also retain significant immunochemical reactivity. Fractions A, B and C (but not D) of the digest all bind antibodies. To characterize further the tryptic digest, 16 peptides from fraction D were isolated and sequence studies on these were carried out.
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40
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41
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Kishinevsky B, Maoz A. ELISA identification ofRhizobium strains by use of enzymelabeled protein A. Curr Microbiol 1983. [DOI: 10.1007/bf01567132] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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42
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43
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Langone JJ. Use of labeled protein A in quantitative immunochemical analysis of antigens and antibodies. J Immunol Methods 1982; 51:3-22. [PMID: 6213721 DOI: 10.1016/0022-1759(82)90376-3] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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44
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Schmeer N, Krauss H. Purification of genus-specific chlamydial antigen and its separation into several components by ion-exchange chromatography. J Clin Microbiol 1982; 15:830-4. [PMID: 7096557 PMCID: PMC272197 DOI: 10.1128/jcm.15.5.830-834.1982] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Sodium deoxycholate-extracted genus-specific chlamydial antigen was purified from contaminating substances by ion-exchange chromatography with DEAE-sephacel, resulting in a decrease in the complement-fixing activity of the antigen, whereas the enzyme-linked immunosorbent assay activity increased. By successive elution with 0.5, 1.0, and 1.5 M acetate buffer at least three clearly separated components were consistently recovered in 14 trials. The identity of these components as genus-specific chlamydial antigen was demonstrated in enzyme-linked immunosorbent assay tests with specific antisera. The antigenic activity of these components was not diminished by prior treatment of the chlamydial particles with pronase. Antiserum prepared by immunization of rabbits with the antigenic component I of an egg-propagated antigen reacted predominantly with the antigenic components I and II of a cell culture-propagated antigen.
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Gee AP, Langone JJ. Immunoassay using 125I- or enzyme-labeled protein A and antigen-coated tubes. Anal Biochem 1981; 116:524-30. [PMID: 7032359 DOI: 10.1016/0003-2697(81)90397-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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47
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Yolken RH, Leister FJ. Staphylococcal protein A-enzyme immunoglobulin conjugates: versatile tools for enzyme immunoassays. J Immunol Methods 1981; 43:209-18. [PMID: 6267138 DOI: 10.1016/0022-1759(81)90025-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
This report describes the use of peroxidase-labeled staphylococcal protein A to prepare conjugates suitable for direct enzyme immunoassays (EIAs). Such conjugates were used to develop direct EIA systems for the measurement of two antigens associated with human infections, human rotavirus and Haemophilus influenzae type b polysaccharide. Both systems were as sensitive or more sensitive than currently available EIAs for the measurement of standard antigens. In addition, both systems could be utilized to correctly identify the antigens in clinical specimens obtained from sick patients. Efficient enzyme conjugates prepared with enzyme-labeled staphylococcal protein A were simple to formulate providing that immunoglobulin of the appropriate animal species was available as the source of antibody. The use of such conjugates might increase the availability of practical EIA systems for the measurement of a wide range of medically important antigens.
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48
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Buchanan D, Kamarck M, Ruddle NH. Development of a protein A enzyme immunoassay for use in screening hybridomas. J Immunol Methods 1981; 42:179-85. [PMID: 7017005 DOI: 10.1016/0022-1759(81)90147-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A protein A enzyme immunoassay has been developed which is effective in the rapid screening of hybridomas. The detecting reagent is a stable alkaline phosphatase-protein A conjugate, prepared by a simple, inexpensive, single-step procedure. The assay requires small amounts of antigen to coat microtiter wells (less than 25 microgram/well) and can be evaluated visually or with a spectrophotometer. It compares favorably in sensitivity to a protein A-radioimmunoassay and enjoys considerably lower backgrounds than that popular screening procedure.
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Elwing H. Water wettability of antigen and antigen-antibody layers on solid surfaces studied by the contact angle measurement technique. FEBS Lett 1980; 116:239-42. [PMID: 7190932 DOI: 10.1016/0014-5793(80)80653-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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50
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Yolken RH, Stopa PJ. Comparison of seven enzyme immunoassay systems for measurement of cytomegalovirus. J Clin Microbiol 1980; 11:546-51. [PMID: 6253515 PMCID: PMC273458 DOI: 10.1128/jcm.11.6.546-551.1980] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The relative sensitivities of seven different enzyme immunoassay (EIA) systems for the measurement of cytomegalovirus (CMV) were compared. Methods which used two separate antisera to CMV provided the greatest degree of sensitivity. Equivalent sensitivity was noted with the use of either enzyme-labeled antiglobulin or unlabeled staphylococcal protein A and rabbit enzyme-antienzyme complex to measure the second anti-CMV antibody bound to the solid phase. Single-antibody methods were less sensitive than the double-antibody methods but were more sensitive than an inhibition EIA. However, the sensitivity of the inhibition EIA was improved when CMV-antibody complexes were separated from unreacted antibody by means of precipitation with polyethylene glycol. Double-antibody EIA systems are preferable when antisera prepared in two different animal species are obtainable. However, a number of single-antibody EIA systems can be formulated for use in situations where only a single antiserum is available.
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