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J J Haaijman

Publications and source records attributed to J J Haaijman.

At least 19 recordsLinked to original sources

Human interleukin-3 contains a discontinuous zinc binding domain.

The primary structure of human interleukin-3 contains two amino acid consensus sequences at Glutamate 22- Histidine 26 and Histidine 95-Histidine 98, that are characteristic for zinc binding proteins. Therefore, the hypothesis was tested that human interleukin-3 binds zinc specifically by either one or both sequences. Protein dotblotting, followed by probing with radioactive zinc demonstrated specific zinc binding of interleukin-3. Metal specificity was confirmed by competition experiments with 12 other divalent- and trivalent metal ions. Protease treatment combined with plasma desorption mass spectrometry was used to localize the zinc binding domain. Specific zinc binding was restricted to a fragment composed of Threonine 11-Lysine 28 and Asparagine 80-Lysine 100. It was found to decrease by a factor of five when either of these two amino acid stretches was missing. It is concluded that human interleukin-3 is a zinc binding protein. Interleukin-3 zinc binding capacity is largely determined by both moieties of the protein that contain the consensus sequences. In addition we propose that the zinc binding of hIL-3 is involved in (de)phosphorylation of the hIL-3 receptor.

Amino Acid Sequence

Cellular origins of human polymeric and monomeric IgA: enumeration of single cells secreting polymeric IgA1 and IgA2 in peripheral blood, bone marrow, spleen, gingiva and synovial tissue.

Using modified ELISA and spot-ELISA, which permit the parallel determination of heavy chain subclass and the presence of covalently linked J chain, we analysed IgA found in cell culture supernatants or secreted by individual cells from peripheral blood, spleen, bone marrow, gingiva and synovial tissue, with respect to its polymeric or monomeric IgA form (pIgA, mIgA) and IgA1 or IgA2 subclass. The ELISA for determination of J chain in tissue culture supernatants was specific and highly sensitive (detection limit in pg). The results demonstrated that IgA1-producing cells predominated in the tissues examined, and that J chain could be detected in association with the majority of IgA1 and IgA2 secreted by individual cells. With respect to the frequency of cells secreting polymeric, J chain-containing IgA, only 20-30% of cells from the bone marrow were engaged in the synthesis of PIgA. In other tissues the frequency of cells secreting pIgA1 and pIgA2 was considerably higher. Peripheral blood mononuclear cells secreting pIgA2 were easily inducible during stimulation with T cell-dependent pokeweed mitogen, whereas Epstein-Barr virus-transformed cells secreted preferentially mIgA1. When the frequencies of pIgA-, pIgA1- or pIgA2-secreting cells (determined by spot-ELISA technique) from different tissues were correlated with the proportion of pIgA to mIgA (and IgA subclasses) secreted in tissue culture supernatants, data obtained suggest that many individual IgA-producing cells could be engaged in simultaneous secretion of mIgA and pIgA.

Adult

IgA antibodies against phenolic glycolipid I from Mycobacterium leprae in serum of leprosy patients and contacts: subclass distribution and relation to disease activity.

The anti-PGL-I IgA response against phenolic glycolipid I (PGL-I) a specific surface antigen of Mycobacterium leprae, was demonstrated to be essentially of the IgA1 subclass in sera from leprosy patients and contacts. Anti-PGL-I IgA1 mean levels were found to increase significantly from the tuberculoid toward the lepromatous pole of the leprosy disease spectrum, thus resembling the predominating anti-PGL-I IgM response. Furthermore, anti-PGL-I IgA1 values were shown to increase significantly with increasing bacillary load, measured as bacillary index (BI) from skin biopsies. However, a number of BI negative leprosy patients recorded elevated anti-PGL-I IgA1 levels possibly reflecting a persistence of disease activity. Three of 28 household or family contacts of leprosy patients were detected seropositive for anti-PGL-I IgA1. Thus, our results suggest that anti-PGL-I IgA1 may be considered as an additional parameter for the early detection of infection with M. leprae.

Antibodies, Bacterial

Elevated production of polymeric and monomeric IgA1 by the bone marrow in IgA nephropathy.

In bone marrow cultures of 15 patients with primary IgA nephropathy we found significantly (P = 0.02) increased synthesis of both monomeric and polymeric IgA1 compared to 23 controls, by using high performance liquid chromatography (HPLC) fractionation of culture supernatants. The relative contribution of polymeric to total IgA1 produced was not different for the two groups. Two-color immunofluorescence studies of the percentage of bone marrow IgA1 plasma cells able to bind secretory component in vitro showed no difference between patients and controls. In the sera of patients with primary IgA nephropathy the relative contribution of IgA1 polymers to total IgA1 was also similar to controls. These results indicate that in IgA nephropathy, the increased IgA production in the bone marrow is restricted to the IgA1 subclass. The production of both monomeric and polymeric IgA1 is increased in patients during a quiescent phase of the disease.

Adult

Antibodies to a short synthetic peptide related to the hinge segment of human IgG3 recognizes thermally or fixative induced conformational changes in the human IgG3 molecule.

A synthetic decapeptide (SP) was used to produce a murine monoclonal antibody specific for the human IgG3 molecule. Recognition of the IgG3 determinant is heat- and fixation-sensitive in ELISA and immunoenzyme cytology, respectively. The antibody specifically recognizes a sequence from the hinge region of IgG3, but only when subtle alterations in the conformation are induced by mild heating (greater than 40 degrees) and subsequent stabilization by means of electrostatic interactions in solid-phase assays or by fixation with formalin acetic acid mercury chloride. The structure of the human IgG3 molecule is especially sensitive to microenvironmental influences, as can be concluded from its behaviour under various physicochemical conditions. To this, we add that the immunogenic determinants in the structure of relatively flexible parts of this protein can be severely altered by the routine application of fixation methods. It is shown that these changes can also be of importance in the recognition of antigen by monoclonal antibodies.

Antibodies, Monoclonal

IgG subclass distribution in juvenile human tonsil: IgG3 and IgG4 results of specific antibody production using synthetic peptides.

A decapeptide with a sequence corresponding to a part of the hinge region of human IgG3 was used to prepare a mouse monoclonal antibody (Mab 330-2.2). The Mab recognized IgG3 in ELISA only when the IgG3 was denatured by mild heat. Mab specificity in immunohistochemistry was calibrated with a number of reference Mabs obtained through a WHO/IUIS collaborative study. Finally, Mab 330-2.2 was used in conjunction with a set of other isotype specific Mabs to study the (sub)class distribution of cytoplasmic Ig containing cells in palatine tonsil. IgG3 within the IgG class was strongly over-represented in our tonsil material if compared to the representation of IgG3 in serum.

Antibodies, Monoclonal

Immunofluorescence: quantitative considerations.

The combination of the specificity of the antigen-antibody interaction with the sensitivity of fluorescence detection and quantitation yields one of the most widely applicable analytical tools in cell biology. Immunofluorescence (IF) signals can be measured with microscopes or flow cytometers. Choice for either of the two systems depends on the type of preparation (cells, tissues, etc.), on the type of required information (morphology, distribution, quantitation) and on the number and quality of the samples. In IF a choice has to be made for the most appropriate fluorochromes, reagents, equipment and preparative procedure, respectively, the right balance between lightsource, objective, eye pieces and filters should be sought in microscopy as well as in flow cytometry. The quantitative influence is reported of each of these variables on the eventual fluorescence intensity. New developments are appearing in IF technology. These include laser-scan microscopy, point-addressable optical sensors, phosphorescence microscopy and more sophisticated flow cytometers that allow some morphometry. The possible uses of these systems is discussed.

Fixatives

The bone marrow as production site of the IgA deposited in the kidneys of patients with IgA nephropathy.

Patients with primary IgA nephropathy have increased plasma levels of polymeric IgA1 and deposits of IgA1 in their kidneys. The origin of this material is unknown. The production of IgA and its subclasses was investigated in the bone marrow of 14 patients and 19 controls using two colour immunofluorescence and tissue culture. Patients had an increase in the percentage of plasma cells containing IgA (45.8 +/- 7.2 mean +/- s.d.) compared to controls (40.1 +/- 10.5) (P = 0.08). IgA plasma cells containing subclass IgA1 were significantly (P less than 0.01) increased in patients (89.9 +/- 2.7%) compared to controls (84.1 +/- 6.7%). Correspondingly IgA plasma cells containing subclass IgA2 were significantly decreased (P less than 0.01) in patients (7.4 +/- 3.0%) compared to controls (13.5 +/- 5.9%). Production of IgA in bone marrow culture in patients was increased (1,684 +/- 1,151 ng/culture) compared to controls (1,087 +/- 937), but this difference was not significant (P = 0.2). However, in patients the IgA1 subclass contributed significantly (P less than 0.01) more to the IgA synthesis in culture (ratio of IgA1 over IgA: 0.96 +/- 0.02) than in controls (ratio 0.90 +/- 0.06). These findings suggest that the bone marrow may well be the site of long-term overproduction of the IgA1 found in the circulation and mesangial deposits in IgA nephropathy.

Adolescent

The effect of divalent and univalent binding on antibody titration curves in solid-phase ELISA.

This paper describes the influence of antigen coating concentration, epitope density per antigen molecule and anti-immunoglobulin reagents on antibody titration curves in solid-phase ELISA. Based on results obtained with fluorescein as the hapten and monoclonal anti-fluorescein antibody, which were confirmed in another antigen-antibody system, it is concluded that: (a) Antibody titration curves are independent of antigen-coating concentration in a limited range of concentrations only. (b) The complex between one antibody and two epitopes ('divalent binding') is more stable than the complex between one antibody and one epitope ('univalent binding). The ratio between divalent and univalent binding depends on the epitope density per antigen molecule and on the antigen-coating concentration. (c) The prozone phenomenon can be explained by an increased instability of plate bound antibodies due to a shift from divalent to univalent binding. (d) In solid-phase ELISA a correct evaluation of the antiserum specificity can be performed only if it is ascertained that all target antigens are coated under saturating conditions.

Animals

Different subclass distribution of IgA-producing cells in human lymphoid organs and various secretory tissues.

A highly reproducible paired immunofluorescence staining method was used to map the relative distribution of IgA1- and IgA2-producing cells in peripheral lymphoid organs and various secretory tissues. Spleen, peripheral lymph nodes, and tonsils all contained a marked predominance (91 to 95%) of IgA1 immunocytes. However, striking variations were demonstrated among the secretory tissues with regard to the median proportion of IgA1-producing cells: nasal mucosa, 96%; lacrimal glands, 81%; major salivary glands, 66%; mammary glands, 63%; gastric and proximal small intestinal mucosa, 84 to 77%; ileum, 55%; and large bowel, 41%. Thus, IgA2 production is relatively enhanced mainly in the distal gut and in mammary and salivary glands, in that order.

Animals

Assay of human IgA subclass antibodies in serum and secretions by means of monoclonal antibodies.

Solid-phase radioimmunoassays have been developed for the detection and quantification of human serum and secretory IgA antibodies to a variety of food, bacterial and viral antigens. Monoclonal antibodies specific for IgA1 and IgA2 and capable of binding to serum and secretory IgA were used. The assays were calibrated by reference to standard serum or purified myeloma proteins bound to solid-phase anti-immunoglobulin reagents, and sigmoid calibration curves were constructed by means of computer programs using 4-parameter logistic or weighted logit-log principles. Polymeric and monomeric forms of IgA antibodies were assayed in fractions separated by high performance size exclusion chromatography. These techniques have demonstrated the expected predominance of IgA1 antibodies in serum, and these included polymeric forms. Saliva contained both IgA1 and IgA2 antibodies, and increased proportions of IgA2 antibodies to lipopolysaccharides and lipoteichoic acid were observed.

Antibodies, Anti-Idiotypic

Fluorescein and tetramethyl rhodamine as haptens in enzyme immunohistochemistry.

Fluorescein (Fl) and tetramethyl rhodamine (Rh) were evaluated as possible candidates for a double hapten sandwich system in enzyme immunohistology. Monoclonal antibodies were raised against Fl and Rh. Their fine-specificity was tested with a competition-like assay. A pair of Mab's was selected for immunohistology in which they functioned as a bridge between Fl/Rh conjugated antibodies and Fl/Rh labeled peroxidase and alkaline phosphatase, respectively. The binding of fluorescein labeled antibodies could be successfully demonstrated in histological slides. A large variability in the efficacy of staining was observed in the case of rhodamine labeled antibodies. The phenomenon is explained by assuming that tetramethyl rhodamine isothiocyanate reacts preferentially with lysine residues near to, or embedded in, hydrophobic regions in a protein. This condition may reduce the accessibility of the Rh moiety for anti-Rh antibodies.

Alkaline Phosphatase

Monoclonal antibodies against different domains of human IgA: specificities determined by immunoblotting and haemagglutination-inhibition.

The specificity of 14 monoclonal antibodies has been determined by immunoblotting (IB) and haemagglutination-inhibition (HAI) analysis using IgA1 and IgA2 myeloma proteins and eight different IgA1 fragments. Two antibodies probably recognized epitopes on the CH1 domain of IgA. They reacted with all Fab-containing fragments irrespective of whether these originated from the same or different IgA proteins. Seven antibodies were directed against epitopes on the CH2 domain. These antibodies were reactive with F(abc)2 fragments. They failed to react with Fab, Fab' and F(ab')2 fragments. Two out of these seven antibodies did not react with two-chain IgA half-molecules and Fabc fragments containing a single heavy and a single light chain. This suggests that these two antibodies recognized an epitope whose structure is dependent on disulfide linked heavy chains. Five other antibodies showed specificity for the CH3 domain. They were reactive with all CH3-containing molecules, irrespective of whether they comprised one or two alpha chains. Our study demonstrates that IB is an appropriate technique to determine domain specificity of monoclonal anti-immunoglobulin reagents. Although the IB tests were performed on denatured proteins the results agreed surprisingly well with those of the HAI analyses. Moreover, the IB technique could be used on fragments which could not be purified well enough for HAI analyses.

Antibodies, Monoclonal

Characteristics of IgA deposits in liver and skin of patients with liver disease.

The presence of IgA deposits in a continuous pattern along hepatic sinusoids is a specific entity for alcoholic liver disease. In superficial skin blood vessels of patients with liver disease, IgA deposits can occur. The authors characterized the deposits for IgA-subclass epitope expression and for macromolecular configuration (assessment of [hidden] J-chain determinants and of secretory component-binding capacity). A variety of monoclonal anti-IgA-subclass reagents were applied, which proved to be specific in control experiments on blastoid cells generated by pokeweed mitogen stimulation of blood mononuclear cells and frozen tissue sections of normal jejunum. IgA1 is the major component in IgA deposits in liver (n = 83) and skin (n = 31) of patients with liver disease. Macromolecular IgA is detectable in only one-fifth of the cases. The authors' data do not indicate that hepatic IgA deposits in liver disease are of gastrointestinal origin. Out of the circulating IgA pool, IgA1 appears to be most capable of being deposited in tissue.

Histocytochemistry

Production and characterization of pepsin fragments of human IgA1 to determine domain-specificity of monoclonal anti-IgA antibodies.

Eight human IgA1 myeloma proteins were analysed by SDS-PAGE. These experiments showed that purified IgA1 proteins comprise both fully S-S bonded and partly S-S bonded molecules. Pepsin digestion of the IgA1 proteins yielded three four-chain and two two-chain fragments. The four-chain fragments are likely to be derived from intact IgA through cleavage of its alpha chains at different sites: between the CH2 and CH3 domains or in the hinge region. The occurrence of F(abc) (ab') fragments, with alpha chains of different lengths, showed that the alpha chains of IgA can be cleaved independently at the hinge region site. The two-chain pepsin fragments must originate from IgA molecules, which lack inter-assay-chain disulphide linkages. The fragments F(abc)2 and Fabc tended to form dimers, probably through non-covalent interactions of their CH2 domains. An immunoblotting method was used to identify Fd-, CH2- and CH3-specific anti-IgA antibodies. The CH2-specific antibodies could be subdivided into antibodies recognizing an isotype present on both four-chain and two-chain molecules or on two-chain molecules only.

Antibodies, Monoclonal