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M Harboe

Publications and source records attributed to M Harboe.

At least 91 records · Page 5Linked to original sources
PubMed1991

C3 activation products, C3 containing immune complexes, the terminal complement complex and native C9 in patients with rheumatoid arthritis.

Complement activation products, C9 and C3-containing circulating immune complexes (CIC), were evaluated in plasma and synovial fluid (SF) from patients with rheumatoid arthritis (RA) and osteoarthritis. C3 activation products and the fluid phase terminal complement complex were considerably elevated in SF from RA patients reaching levels five- to eighttimes that in plasma, consistant with a local activation of the whole cascade in the joints. The results emphazise the importance of detecting C3 activation by neoepitope expression instead of single fragment determinations. The concentration of native C9 was lower in synovial fluid compared with plasma, consistant with the excessive local complement activation. Increased CIC levels which correlated with the degree of complement activation were also found in the SF from the RA patients.

Adult↗
PubMed1991

Purification and characterization of the 30,000 dalton native antigen of Mycobacterium tuberculosis and characterization of six monoclonal antibodies reactive with a major epitope of this antigen.

The 30,000 dalton native antigen of Mycobacterium tuberculosis is a major constituent of this organism and is secreted into culture medium. We purified this antigen by ammonium sulfate precipitation, ion-exchange chromatography, and reverse-phase high-performance liquid chromatography to yield a single 29 to 30 kd component. The first 20 N-terminal amino acid sequence was determined and found to be identical to that reported for M. bovis alpha-antigen. Immunoelectrophoresis studies demonstrated the purified 30,000 dalton antigen to be immunologically identical with antigen 6 and antigen 85B. The 30,000 dalton native antigen was a potent skin test antigen in sensitized guinea pigs. Six immunoglobulin G1 murine monoclonal antibodies against the 30,000 dalton antigen were generated. By enzyme-linked immunosorbent assay and western immunoblotting, all six monoclonal antibodies reacted with the 30,000 dalton antigen, perhaps with the same epitope. When used with culture filtrates of other mycobacteria, the monoclonal antibodies demonstrated reactivity with M. gordonae and M. kansasii and to a lesser extent with M. avium and M. scrofulaceum.

Amino Acid Sequence↗
PubMed1991

Complement activation and bioincompatibility. The terminal complement complex for evaluation and surface modification with heparin for improvement of biomaterials.

The degree of biocompatibility of biomaterials can be evaluated using various assay systems detecting activation of the blood cascade systems, leukocytes or platelets. Activation of complement is one mechanism associated with adverse effects observed when bioincompatible materials are used. We present data showing that the terminal complement complex, an indicator of terminal pathway activation, is suitable for evaluation of biocompatibility of biomaterials such as cardiopulmonary bypass devices. Furthermore, our results suggest that bioincompatibility is improved when artificial surfaces are modified with end point attached functionally active heparin.

Complement Activation↗
PubMed1990

Integration of monoclonal antibodies in quantitative immunoelectrophoresis by indirect immunoprecipitation.

Characterization of the specificity of monoclonal antibody in crossed immunoelectrophoresis has been achieved by mixing the monoclonal antibody with mycobacterial antigen in the circular antigen well. After electrophoresis in the first dimension, the separated antigens and antigen complexed with monoclonal antibody were run into an intermediate gel containing rabbit anti-mouse immunoglobulin and a top gel with polyvalent rabbit anti-BCG immunoglobulin. Monoclonal antibody with bound antigen precipitated in the intermediate gel while the other antigens precipitated in their reference positions. The method was simple, efficient and sensitive. Selected monoclonal antibodies were used to demonstrate the characteristic features of the method. In rocket immunoelectrophoresis the rocket height of a monoclonal antibody may be significantly altered by adding the relevant antigen. This principle can be exploited when the polyvalent antibodies do not precipitate the antigen, and it may be used for efficient screening of monoclonal hybridoma culture supernatants. This approach may permit the quantitation of an antigen when only monoclonal antibody is available.

Animals↗
PubMed1990

Carrier effect of concanavalin A-reactive and -non-reactive material in tuberculin PPD.

Tuberculin purified protein derivative (PPD) is a very potent T-cell reactive material in tuberculin-positive individuals, but the components responsible for this reactivity have not been adequately defined. Three purified mycobacterial proteins (MPB70, the BCG 65-kDa protein, and BCG antigen 85B) with different degrees of temperature sensitivity were iodine-labelled and added to BCG culture fluid, and the mixtures were autoclaved at 120 degrees C for 30 min to simulate the initial heating procedure used to prepare PPD. SDS-PAGE followed by protein staining and autoradiography showed that the banded pattern of unheated culture fluid was completely lost after heating, and only the labelled MPB70 preparation retained most of the radioactivity in a fraction with soluble protein of the same size. Most mycobacterial proteins are extensively denatured by these procedures, which explains the previous extensive difficulties in isolating defined constituents from PPD to characterize their behaviour in B- and T-cell reactions. In assays for the carrier effect of NIP-PPD for induction of anti-NIP production in BCG-vaccinated mice, the active fractions were heterogeneous in lectin reactivity as well as in SDS-PAGE. It appears most likely that a number of Mycobacterium tuberculosis proteins give rise to core peptides which resist proteolysis and heat denaturation to possess powerful T-cell-activating ability.

Animals↗
PubMed1990

Evidence for three separate genes encoding the proteins of the mycobacterial antigen 85 complex.

The secreted Mycobacterium bovis BCG antigen 85 complex, which is known to bind to human fibronectin, consists of three closely related cross-reacting antigens. Amino-terminal sequence analysis of the purified proteins showed distinct differences. Data are presented to show that the three components are produced by individual cells, which indicates that three separate genes are involved.

Amino Acid Sequence↗
PubMed1990

Protein G-based enzyme-linked immunosorbent assay for anti-MPB70 antibodies in bovine tuberculosis.

MPB70 is a highly species specific protein which is secreted from Mycobacterium bovis during culture. To investigate whether antibodies against MPB70 can be used as an indicator of infection with M. bovis, an enzyme-linked immunosorbent assay was developed, based on the use of biotinylated protein G, to provide a common indicator for antibody formation in different species. During experimental infection with M. bovis in cattle, a characteristic pattern of anti-MPB70 antibody production was observed with an initial flat plateau followed by a marked rise 18 to 20 weeks after infection. Skin testing with bovine tuberculin purified protein derivative (PPD), which was shown to contain antibody-reactive MPB70, was a potent stimulator of antibody production in infected animals. In experimentally infected cattle, we observed an inverse relationship between antibody activity and delayed-type hypersensitivity skin test reactions. In natural M. bovis infections, skin testing with PPD was also a potent stimulator of anti-MPB70 formation. Comparison between the enzyme-linked immunosorbent assay for antibodies to MPB70 and that for antibodies to the widely cross-reacting M. bovis BCG antigen 85B in animals with M. bovis, Mycobacterium avium, Mycobacterium paratuberculosis, and Corynebacterium pseudotuberculosis infections showed that formation of antibody to MPB70 was highly specific for infection with M. bovis. The use of an MPB70-containing PPD preparation for skin testing followed by this anti-MPB70 assay is a highly specific indicator of M. bovis infection. Adjustment of the test conditions is expected to provide an increased sensitivity of the procedure for the diagnosis of natural M. bovis infections.

Animals↗
PubMed1990

Quantitative and qualitative studies on the major extracellular antigen of Mycobacterium tuberculosis H37Rv and Mycobacterium bovis BCG.

The Mycobacterium tuberculosis antigen 85 is a biologically important antigen. Tuberculosis patients may have strong antibodies against it, and their peripheral blood mononuclear cells respond to it with gamma-interferon production and lymphocyte proliferation. Antigen 85 is actively secreted into the culture medium during culture in vitro and is known to bind human fibronectin. A double-antibody enzyme-linked immunosorbent assay (ELISA) for quantification of antigen 85 is described. A mouse monoclonal antibody, HYT27, was used as capture antibody in the assay. HYT27 was characterized in crossed immunoelectrophoresis and found to bind all three components of the antigen 85 complex. By radioimmunoassay, HYT27 was found to bind equally well to antigens 85A and 85B. In the ELISA assay, a rabbit anti-antigen 85 antiserum was used in the second antibody layer. The specificity of the assay was tested using several different antigen preparations. The purified BCG 85A and 85B components were compared, and there was a 10 times lower sensitivity for antigen 85A due to weaker rabbit antibodies toward this component. The purified components MPT44 and MPT59 from M. tuberculosis H37Rv were compared with the components of BCG and found to correspond to BCG 85A and 85B, respectively. Mycobacterium kansasii and Mycobacterium avium both contained partially identical antigens. Small amounts of antigen 85 were detected in Mycobacterium leprae sonicates. Detecting antigen 85 by sensitive methods may be of great value in the early diagnosis of mycobacterial disease.

Antibodies, Monoclonal↗
PubMed1989

[Norwegian nomenclature in immunology].

Immunology represents one of the medical disciplines that has witnessed the fastest growth in new knowledge in recent decades. In the international journals the new concepts are introduced using English terminology. Norwegian immunologists are almost exclusively exposed to English immunological literature, and are therefore prone to adopt English rules of syntax when translating this literature into Norwegian. Two years ago a nomenclature-committee was established, with the mandate to ensure improved translations and, where relevant, to point out rules of syntax. The article presents the results from the work of this committee.

Allergy and Immunology↗
PubMed1988

The antigens of Mycobacterium tuberculosis, H37Rv, studied by crossed immunoelectrophoresis. Comparison with a reference system for Mycobacterium bovis, BCG.

On the basis of a previously developed reference system for Mycobacterium bovis, BCG, in crossed immunoelectrophoresis (CIE), antigens of Mycobacterium tuberculosis were identified in an analogous system. A majority of the numbered lines in the BCG system were also present and identified in the M. tuberculosis system. The corresponding antigens in the two systems were identified by dual dilution in CIE, and using monospecific antisera and monoclonal antibodies. Some of the antigens were specifically identified by the demonstration of enzyme activity and by means of hydroxyapatite, concanavalin A (Con A), EDTA, and blue-Sepharose. Three antigens (nos 10, 78, and 81), which were found in high concentrations in M. tuberculosis culture fluid, were not identified or were present in low concentrations in BCG culture fluid. The high percentage of corresponding antigens confirms that there is a very close taxonomic relationship between BCG and M. tuberculosis. Corresponding antigens in BCG and M. tuberculosis did not differ in electrophoretic mobility in the antigenic preparations studied.

Antigens, Bacterial↗
PubMed1988

Characterization of fibronectin-binding antigens released by Mycobacterium tuberculosis and Mycobacterium bovis BCG.

Fibronectin (FN)-binding antigens are prominent components of short-term culture supernatants of Mycobacterium tuberculosis. In 3-day-old supernatants, a 30-kilodalton (kDa) protein was identified as the major FN-binding molecule. In 21-day-old supernatants, FN bound to a double protein band of 30 and 31 kDa, as well as to a group of antigens of larger molecular mass (57 to 60 kDa). FN-binding molecules in this size range, but not of 30 to 31 kDa, were also found in sonicates. We showed that the 31- and 30-kDa FN-binding bands correspond to components A and B of the BCG85 complex, previously shown to be abundant in culture supernatants of Mycobacterium bovis BCG. Thus, a polyclonal antibody to the BCG85 complex bound to the 30- and 31-kDa antigens and inhibited binding of FN to them on immunoblots of the culture filtrates. Similarly, FN bound to the purified components of the BCG85 complex, and this binding was blocked by the antibody. A monoclonal antibody, HYT27, also bound both to the BCG85 components A and B and to the 30- and 31-kDa FN-binding molecules of M. tuberculosis, but it did not block the binding of FN. Related molecules appear to be present on the surface of BCG and to mediate the binding of BCG to FN-coated plastic surfaces, since this binding could also be blocked by the polyclonal anti-BCG85 antibody and by the purified components of BCG85, particularly component A, but not by monoclonal antibody HYT27. The binding of these mycobacterial antigens to FN appears to be of very high affinity, and we suggest that this property of major secreted antigens of M. tuberculosis indicates an important role in mycobacterial disease and in the binding of BCG to tumor cells during immunotherapy of bladder cancer.

Antigens, Bacterial↗
PubMed1988

Rheumatoid factors in leprosy and parasitic diseases.

Rheumatoid factors (RFs) occur with higher frequency and in higher titres in multibacillary forms of leprosy and several parasitic diseases than in healthy controls. The selection of controls is essential in studies of this kind. They should be individuals without signs of the disease under study living under similar socioeconomic conditions as the patients in the endemic country. In three studies where this matter was considered, RFs in lepromatous leprosy and Chagas' disease reacted more strongly with rabbit than human IgG, a feature generally considered to be quite restricted to rheumatoid arthritis. RFs interfere in various test systems, particularly in inducing false positive reactions for specific IgM antibodies in parasitic and other infectious diseases. Model experiments in rats, in vitro culture studies, and observations in humans indicate that RFs may have a protective role in trypanosome infections, malaria and schistosomiasis respectively.

False Positive Reactions↗
PubMed1988

In vitro synthesis of antimycobacterial antibodies with different specificities in various tissues of leprosy patients.

For the detection of the synthesis in vitro of anti-Mycobacterium leprae antibodies in various tissues of leprosy patients, biopsy specimens of skin lesions, nasal mucosa, larynx, lymph nodes, and bone marrow were cultured in a medium containing 14C-labeled lysine and isoleucine. The culture fluids were analyzed by crossed immunoelectrophoresis with intermediate gel and autoradiography. The results show that synthesis of anti-M. leprae antibodies occurs at the investigated sites of leprosy patients and that the specificities of the synthesized antibodies differ between sites in individual patients. It is conceivable that these antibodies play a role in the local defense against M. leprae.

Antibodies, Bacterial↗
PubMed1987

Comparison of antigens and antisera in crossed immunoelectrophoresis by dual dilution.

The localization of individual precipitates in the crossed immunoelectrophoresis (CIE) pattern is an important feature for their identification, but in a given system this pattern may vary markedly when different antigen preparations or antisera are used. Two different antigen preparations or antisera may be compared by mixing them in various proportions in a set of four CIE plates. The amounts of the preparations to be compared are selected to obtain a gradual change in position of individual precipitates if differences are encountered. Similarities between antigen or antibody preparations are recorded when the positions of precipitates remain unchanged. The technique is particularly valuable for comparing complex patterns with a large number of precipitate lines.

Animals↗
PubMed1987

Purification, characterization and identification of a 32 kDa protein antigen of Mycobacterium bovis BCG.

An immunogenic protein called P32 has been purified from Sauton zinc deficient culture filtrate of Mycobacterium bovis BCG using successively hydrophobic chromatography on Phenyl-Sepharose, ion exchange on DEAE-Sephacel and molecular sieving on Sephadex G-100. The final preparation was found to be homogeneous as based on several analyses. This P32 protein was a constituent of BCG cells grown in normal conditions. It represented about 3% of the soluble fraction of a cellular extract, and appeared as the major protein released in normal Sauton culture filtrate. This protein was found to have a molecular weight of 32,000 by SDS-polyacrylamide gel electrophoresis and in molecular sieving. Its amino acid composition showed an abundance of acidic amino acids (or their amides). The NH2-terminal amino acid sequence (6 amino acids) was determined. Purified P32 was tested by various crossed immunoelectrophoresis techniques, and was shown to belong to the antigen 85 complex in the reference system for BCG antigens. It was more precisely identified as antigen 85A. The protein antigen elicited a weak delayed hypersensitivity reaction in guinea pigs sensitized with heat-killed or living BCG. No delayed hypersensitivity reaction was observed in living BCG sensitized mice, however, it induced significant amounts of gamma interferon in cultured spleen cells from BCG-sensitized mice. Moreover, P32 either pure or as part of BCG soluble extract promoted substantial antibody levels when injected in rabbits.

Amino Acids↗
PubMed1987

Immunohistochemical detection of the membrane and fluid-phase terminal complement complexes C5b-9(m) and SC5b-9. Consequences for interpretation and terminology.

Activation of the terminal pathway of complement on a membrane results in the generation of the membrane-damaging terminal C5b-9(m) complement complex, whereas the non-lytic water-soluble SC5b-9 complex is formed when complement is activated in the fluid phase. Both forms of the terminal complement complex (TCC) can be immunohistochemically detected, but not distinguished, by antibodies recognizing neoantigens in the complexes. By means of monoclonal antibodies against C9 neoantigens and against the S-protein, it was demonstrated that deposits of the TCC in tissue sections may be either in the form of C5b-9(m) or SC5b-9. The consequences of this for the interpretation of the histochemical data and the terminology of the two complexes are discussed.

Adult↗