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J Biewenga

Publications and source records attributed to J Biewenga.

At least 55 records · Page 3Linked to original sources
PubMed1987

IgA nephropathy is not induced in mice by oral administration of TNP-conjugated ovalbumin.

An IgA nephropathy model based on long-term oral administration of protein antigens was evaluated in three mouse strains using trinitrophenyl (TNP)-conjugated ovalbumin. Administration of the antigen for 14 weeks did not induce a significant IgA response nor deposition of IgA in the mesangium in any of the mouse strains. If, however, serum IgA anti-TNP antibodies were induced by intraperitoneal injection of anti-TNP producing MOPC-315 tumor cells, subsequent intravenous injection of antigen resulted in the deposition of IgA immune complexes in the mouse kidneys. Hematuria did not occur. In conclusion, previous data showing that long-term oral administration of protein antigens induces mesangial IgA deposits could not be confirmed with TNP ovalbumin. However, mesangial IgA deposits were obtained in animals treated with MOPC-315 tumor cells as described by Rifai et al. [J. exp. Med. 150: 1161-1173, 1979].

Animals↗
PubMed1986

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↗
PubMed1986

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↗
PubMed1985

Binding of human IgA fragments to protein A-Sepharose studied with an ELISA method.

An enzyme-linked immunosorbent assay method was developed to investigate the binding of IgA fragments to protein A. The method proved to be specific and highly sensitive. Contamination with IgG did not interfere with the detection of IgA binding to protein A, and less than 10 ng of IgA could be detected. Four of nine IgA proteins tested bound to protein A to different extents. The binding was not disturbed by reduction and alkylation of the IgA proteins. Four-chain F(abc)2 and F(ab')2 fragments of the protein A-reactive IgA proteins also bound to protein A. On reduction and alkylation these fragments formed two-chain Fabc and Fab' fragments. Of these, Fabc did not bind, whereas both Fab' and IgA1-protease-produced Fab fragments did bind to protein A. These results demonstrate that the Fab fragment has a binding site for protein A. It is suggested that the protein A binding site is located on the CH1 domain of the IgA1 molecule. On Fabc fragments this binding site may be blocked because of structural alterations.

Binding Sites, Antibody↗
PubMed1983

Production and characterization of antibodies specific for domains of human IgM.

A method of preparing antibodies against c mu 3 and c mu 4 domains of human IgM is described. c mu 3- and c mu 4-binding antibody fractions were isolated by affinity chromatography from IgG fractions of antisera raised against Fc5 mu and Fc mu' fragments. c mu 3 and c mu 4 fragments had been prepared from human IgM kappa (Key) by hot trypsin digestion. Haemagglutination inhibition tests showed that the c mu 4-binding fraction only reacted with c mu 4 fragments. The c mu 3-binding fraction reacted with c mu 3 fragments but showed a minor reaction with c mu 4 fragments. Immunization with Fc mu' fragments predominantly yielded antibodies against the c mu 3 domain, whereas immunization with Fc5 mu fragments yielded antibodies more directed against the c mu 4 domain. Immunization with isolated c mu 4 fragments led to the production of antibodies which reacted with the isolated c mu 4 domain but not with the c mu 4 domain within the larger structures of Fc mu' or Fc5 mu fragments.

Antibodies↗
PubMed1983

Allotypic and isotypic aspects of human immunoglobulin A.

The location of isotypic, isoallotypic and allotypic determinants is reviewed in the light of data obtained when specific antisera are tested with proteolytic fragments of IgA molecules or mutants of IgA obtained from patients with alpha-heavy chain disease. Isotypic determinants are distributed throughout the alpha chain constant regions although when intact IgA proteins are used as immunogens the CH3 domain is immunodominant. Alpha 1 subclass specific isotypic determinants are present in both Fab and Fc fragments. Amino acid sequence analysis suggest that alpha 1 subclass isotypic determinants depend on substitution in the CH1, hinge and/or CH2 domain. The isoallotypic determinants nA2m(2) appears to be located on the CH1 domain and appears to require disulphide-linked alpha chains for its expression. The allotypic determinant A2m(2) appears to be located in the CH3 domain involving residues 428, 458 and/or 467. The latter residues are present in both A2m(1) and A1 proteins which indicates that for A2m(1) to be the antithetical determinant of A2m(2), the determinant formed by residues 428, 458 and/or 467 in these proteins must be influenced by subclass differences which allows its expression in A2m(1) proteins and not in A1 proteins.

Amino Acid Sequence↗
PubMed1983

Distribution of antigenic determinants on human IgA1.

The distribution of antigenic determinants on human IgA was studied with fragments and mutants of IgA1. F(abc)2 and Fabc, lacking the CH3 domain, F(ab')2 and Fab', lacking the CH2 and CH3 domain, Fab that further lacks most of the hinge region, and Fc fragments were included in our investigations. Antibodies specific for the CH3 domain of IgA1 were found in antisera raised against an alpha 1-HCD protein and in anti-Fc alpha antisera. The antisera detected different antigenic determinants on CH3 as was shown by inhibition with sera from nonhuman primates. An anti-Fc5 mu antiserum detected a determinant on Fc common to IgA and IgM. The serum of an IgA-deficient individual reacted with a determinant on CH2 of four-chain molecules only. A subclass-specific anti-Fabc antiserum detected a determinant which needed interaction of CH2 and CH1 or the hinge region. Anti-Fab antisera reacted with class or subclass specific determinants on CH1. The isoallotype nA2m(2) is probably located on CH1. Its expression requires two alpha-chains stabilized in a conformation attributed to by CH2.

Animals↗
PubMed1983

Cleavage of protein A-binding IgA1 with IgA1 protease from Streptococcus sanguis.

Protein A-binding fractions of two IgA1 myeloma proteins failed to produce Fc fragments on digestion with IgA1 protease from Streptococcus sanguis. A polymeric protein A-binding IgA1 fraction yielded a protein A-non-binding monomer, which was further cleaved into Fab fragments but it did not yield Fc fragments. The protein A-binding fraction of a monomeric IgA1 yielded an IgA molecule lacking one Fab fragment. Subsequently, the remaining part of its cleaved alpha chain was degraded. Further digestion yielded Fab but not Fc fragments. Similarly, F(abc)2 and Fabc fragments, which lack the CH3 domain (8), yielded Fab fragments but not CH2 domains. Thus, the enzyme in addition to cleaving IgA in the hinge region, under certain conditions, also degrades its Fc fragments.

Binding Sites, Antibody↗
PubMed1983

IgA1 half molecules in human multiple myeloma and the in vitro production of similar fragments from intact IgA1 molecules.

This paper describes an IgA related protein Vla which occurred in the serum and urine of a patient with multiple myeloma. The protein was isolated from urine; it had a molecular mass of 70,000 daltons. It was shown to be a two chain IgA half molecule, consisting of a deleted alpha heavy chain, with a molecular mass of 42,000 daltons, which was disulphide linked to a normal kappa type light chain. Fabc fragments were produced from an unrelated myeloma IgA. These had the same biochemical properties as protein V1a, except for the absence of the disulphide linkage between the deleted heavy chains and the light chains. Protein Vla and the Fabc fragments could both be cleaved by IgA1 protease from Streptococcus sanguis, which indicates the presence of the alpha 1 hinge region. An inventory of its antigenic determinants and their similarity to those of previously characterized F(abc)2 fragments, indicates that protein Vla, like the Fabc fragments, contains the CH1 and CH2 domains, but lacks most of the CH3 domain. The fact that cleavage by IgA1 protease from S. sanguis yields a Fab fragment but fails to yield a CH2 domain demonstrates that cleavage by the enzyme is not only restricted to the Pro227-Thr228 bond in the IgA1 hinge region.

Aged↗
PubMed1982

Binding of human IgA myeloma proteins to protein A. Evidence for different binding mechanisms.

The binding of fifteen IgA myeloma proteins to protein A was studied using affinity chromatography on protein A-Sepharose CL-4B. The percentage to which the proteins bound was variable from 1% to 11% with the exception of IgA(GED) with a binding capacity of 22%, and IgA(KLO) with a binding capacity of 84%. The binding of the proteins IgA(GED) and IgA(KLO) was studied further. IgA(GED) was a monomer, Iga(KLO) a polymer. The characteristics of the binding of these proteins were different. The protein A-reactive fraction of IgA(KLO), but not of IgA(GED) remained fully reactive on repeated protein A chromatography. Furthermore, the binding of IgA(GED) could be reduced to about 3% by either a decrease in pH to 4.5 or an increase in NaCl concentration to 2.0M, whereas the binding of IgA(KLO) was similarly reduced by a decrease in pH but its binding only reduced to half of the original value on a similar increase of NaCl concentration. In addition, F(ab')2 fragments of IgA(KLO), but not of IgA(GED), bind to protein A-Sepharose CL-4B, whereas IgA1 protease-produced Fab fragments of neither of the proteins did so, nor did pepsin-produced Fab' fragments. This suggests that the binding of F(ab')2 fragments of IgA(KLO) needs an intact hinge region.

Binding Sites↗
PubMed1980

Gamma heavy chain disease with an unusually benign course.

Gamma heavy chain disease (gamma HCD) has been found in approximately 60 patients (Franklin 1978) since its discovery in 1964 (Franklin et al. 1964). Clinical features include fever and local or generalized lymphadenopathy which may wax and wane. Patients suffer from an undue susceptibility to infection. Hepatosplenomegaly is common. Blood smears often reveal lymphocytosis with atypical lymphocytes and eosinophilia. The pathological diagnosis is lymphoma or reactive hyperplasia. The disease is often rapidly progressive and fatal. In some patients it runs a more prolonged course. The case we present is remarkable in that the patient has now been in remission for 24 months.

Female↗
PubMed1980

A gamma l heavy-chain disease protein *EST) lacking the entire VH and CHl domains.

A gamma l heavy-chain disease protein (EST) is described which lacks the entire VH and CHl domains and starts with the normal sequence of gamma l H-chains corresponding to the beginning of the hinger region (position 216). Although degradation cannot be excluded with certainty, it is probable that this protein is synthesized as an internally deleted gamma heavy-chain disease protein. Presumably a DNA recombination has occurred resulting in the deletion of the genes of coding for the VH and CHl domains with splicing of the precursor RNA to the sequence coding for the hinge region.

Amino Acid Sequence↗
PubMed1979

A new case of gamma-3 heavy chain disease. Biochemical and immunological investigations.

A new gamma 3 heavy chain disease (gamma 3-HCD) protein (Emm) is described. A molecular weight of 70,000-80,000 daltons was estimated. Antigenic analysis showed that protein Emm lacks light chains and the CH1 domain of heavy chains, whereas the antigenic determinants of the gamma 3 Fc fragment (CH2 and CH3 domains) as well as those of the gamma 3 hinge region were present. Since the anomalous protein was temporarily present in serum Emm, a transient triggering of a cell clone which produces the gamma 3-HCD protein is suggested.

Chemical Phenomena↗
PubMed1978

Antigenic analysis of the IgA component of LDH-IgA immunoglobulin complexes.

LDH-IgA complexes present in some human sera were purified by using affinity chromatography on 5'-AMP-Sepharose 4-B. The IgA component of the purified complexes was analysed in haemagglutination-inhibition tests. Antigenic determinants specific for alpha1 and alpha2 heavy chains and for kappa and lambda light chains were found. Earlier studies suggested that the IgA component is of kappa light chain type only. These different results are discussed. It is suggested that the LDH association site is located in the Fab fragment of the IgA component.

Epitopes↗
PubMed1977

Heterogeneity in electrophoretic mobility and in molecular size of lactate dehydrogenase-immunoglobulin G complexes.

Some human sera have been found to contain lactate dehydrogenase (LDH)-immunoglobulin complexes. A serum with LDH-IgG3 complexes was further analysed. Complexes with different net charge and different molecular size were found. Their isoelectric points, measured by isoelectric focusing, were in the range of pH 6.3 to 7.2. Gel-filtration experiments showed that the molecular size varied from about 300 000 to 1 000 000. Most of the complexes could be precipitated from solution with 30--40% saturated ammonium sulfate or a low ionic strength.

Antigen-Antibody Complex↗
PubMed1975

Lactate dehydrogenase (LDH)-IgG3 immunoglobulin complexes in human serum.

Sera of fifteen patients containing complexes of LDH and IgG were analysed. The LDH-IgG complexes of fourteen of these patients were investigated for their subclass specificity. They appeared to consist of LDH and IgG3, except for one of the patients. The serum of the latter patient also contained complexes of LDH and IgG1. In this serum both types of the immunoglobulin light chains were involved in the formation of the complexes, whereas in the serum of the patients with LDH-IgG3 complexes alone, they only contained one of the two immunoglobulin light chain types; it mainly concerned kappa type. The results of the present study were compared to those of a previous study on LDH-IgA complexes, in which the IgA fraction always contained light chains of kappa type. The mean LDH activity and the heat stability of the LDH activity in the sera with LDH-IgA complexes appeared to be higher than in the sera with LDH-IgG3 complexes. In contrast to complexes of LDH and IgA which occurred in all age groups LDH-IgG3 complexes were mainly found in elderly persons. Although auto-antibodies to different tissue antigens were present in the majority of the sera containing LDH IgG3 complexes, antibodies to LDH could not be demonstrated. A relationship between the presence of the complexes in the serum and a particular disease could not be established.

Adult↗