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D Burger

Publications and source records attributed to D Burger.

At least 73 records · Page 4Linked to original sources
PubMed1993

Identification of the glycosylated sequons of human myelin-associated glycoprotein.

Myelin-associated glycoprotein (MAG) is a neural cell adhesion molecule expressing the L2/HNK-1 carbohydrate epitope. MAG is heavily glycosylated containing 30% carbohydrate by weight. In this study, human MAG glycopeptides were isolated and sequenced. Of the 9 MAG sequons 7 were glycosylated and 1 was partially glycosylated at Asn106. Asn332 which was not recovered in the glycopeptide fractions was probably not glycosylated. Furthermore, preliminary data indicate that all MAG glycosylated sequons might bear the L2/HNK-1 epitope.

Amino Acid Sequence↗
PubMed1993

Sensory neuronopathy and small cell lung cancer: antineuronal antibody reacting with neuroblastoma cells.

The anti-Hu antibody is associated with a paraneoplastic subacute sensory neuronopathy (SSN) described in cases of small cell lung cancer (SCLC). The Hu antigen is a pan-neuronal nuclear antigen with a molecular weight of 35-40 kDa. In this study we demonstrated the presence of the paraneoplastic Hu antigen in different neuroblastoma cell lines. We showed that by indirect immunocytochemistry the serum of patients with SSN and SCLC reacts with the nuclei of neuroblastoma cell lines SKN-SH and LAN-1. Western blot analysis of nuclear extracts from neuroblastoma cell lines SKN-SH, IMR-32 and LAN-1 confirmed the presence of the Hu antigen in these neuroblastoma cell lines. By comparing the immunocytochemical method and the Western blot analysis we were able to determine that the Western blot analysis was a more sensitive test. Screening of the sera of a large population (a total of 122 patients with SCLC, 17 with paraneoplastic disorders as well as 121 controls with other neurological disorders) was performed and showed all 5 of the patients with SSN and SCLC to be positive for the anti-Hu antibody, whereas only 11 of the 122 SCLC patients and none of the controls were positive, thereby suggesting that this test has a very high degree of sensitivity.

Antibodies↗
PubMed1993

Human myelin/oligodendrocyte glycoprotein: a new member of the L2/HNK-1 family.

Myelin/oligodendrocyte glycoprotein (MOG) is a quantitatively minor component of CNS myelin. In this study, human MOG was found to express the L2/HNK-1 epitope on N-linked oligosaccharide structures. This carbohydrate epitope has been found previously in three other characterized human myelin glycoproteins: the myelin-associated glycoprotein, P0, and the oligodendrocyte-myelin glycoprotein. It seems, therefore, that the L2/HNK-1 epitope is expressed frequently in human myelin glycoproteins. Serial lectin affinity chromatography of 14C-glycopeptides indicated that MOG N-oligosaccharide structures are mainly of the complex type, accounting for 77.8% of total radioactivity. In contrast with myelin-associated glycoprotein and P0, which express the L2/HNK-1 epitope on fucosylated structures, in MOG the epitope was detected on all glycopeptide fractions obtained by serial lectin affinity chromatography, although a preferential expression of the L2/HNK-1 epitope was observed on fucosylated structures. Finally, the data indicated that, as for other human myelin glycoproteins, only a subpopulation of MOG molecules expresses the L2/HNK-1 epitope.

Animals↗
PubMed1993

Reactivity to myelin antigens in multiple sclerosis. Peripheral blood lymphocytes respond predominantly to myelin oligodendrocyte glycoprotein.

Although T cell responses to the quantitatively major myelin proteins, myelin basic protein (MBP) and proteolipid protein (PLP), are likely to be of importance in the course of multiple sclerosis (MS), cell-mediated autoimmune responses to other myelin antigens, in particular quantitatively minor myelin antigens, such as myelin-associated glycoprotein (MAG) and the central nervous system-specific myelin oligodendrocyte glycoprotein (MOG), could also play a prevalent role in disease initiation or progression. Highly purified myelin antigens were used in this study to assess cell-mediated immune response to MOG in MS patients, in the context of the reactivity to other myelin antigens, MBP, PLP, and MAG. The greatest incidence of proliferative response by MS peripheral blood lymphocytes was to MOG, as 12 of 24 patients tested reacted and, of these, 8 reacted to MOG exclusively. In contrast, only 1 control individual of 16 tested reacted positively to MOG. The incidence of responses to MBP, PLP, and MAG did not differ greatly between MS patients and control individuals. A predominant T cell reactivity to MOG in MS suggests an important role for cell-mediated immune response to this antigen in the pathogenesis of MS.

Adolescent↗
PubMed1993

The T-lymphocyte response against myelin-associated glycoprotein and myelin basic protein in patients with multiple sclerosis.

In addition to myelin basic protein (MBP), other minor components of myelin, such as myelin-associated glycoprotein (MAG), may be important autoantigens in MS. To determine whether MAG might be involved in an autoimmune reaction in MS, we screened peripheral blood lymphocytes from MS patients and normal subjects for their sensitization to human MBP and MAG antigen using a [3H]thymidine incorporation assay. We recorded three patterns in MS patients: (1) patients who responded neither to MAG nor to MBP (4/11); (2) patients who responded to both MBP and MAG (5/11); and (3) patients who gave an exclusive response to MAG (2/11). The 10 healthy controls did not respond to either MAG or MBP. That some individuals with MS expressed a specific response against MAG and that more than 50% of MS patients expressed a sensitization to MAG suggest that MAG may have a role in the pathogenesis of MS.

Adult↗
PubMed1992

Preoperative care of infants with nephroblastoma. The International Society of Pediatric Oncology 6 experience.

The International Society of Pediatric Oncology (SIOP) recommends preoperative treatment in the management of eligible patients with Wilms' tumor. Until 1980, children younger than 12 months of age (infants) at diagnosis had been excluded from the SIOP trials. SIOP 6, conducted from 1980 to 1987, was the first SIOP study to include infants older than 6 months of age. This retrospective analysis of 145 infants registered to SIOP 6 demonstrates that in infants older than 6 months and having favorable histology (FH), a two-drug preoperative chemotherapy (CT) regimen of 4 weeks significantly ameliorated stage distribution as determined at delayed surgery but did not affect a good outcome. However, the CT dose utilized in SIOP 6 resulted in an unacceptable toxicity in this age group, and SIOP 9, the new SIOP study of Wilms' tumor, recommends a reduced dose of CT in infants. Preoperative CT is not recommended in infants younger than 6 months of age. Specifically, the high incidence (29%) of mesoblastic nephroma in this age group does not justify such an approach. Histopathologic diagnosis should be obtained in these patients before any treatment.

Age Factors↗
PubMed1992

Childhood peripheral neuropathy with autoantibodies to myelin glycoprotein P0.

The serum of a 4-year-old child with severe hypertrophic peripheral neuropathy contained high-titer polyclonal antibodies, mainly of IgG class, reacting with the 30-kd P0 glycoprotein of peripheral nerve. This was demonstrated by indirect immunofluorescence, immunoblot analysis of myelin proteins, and enzyme-linked immunosorbent assay with purified P0 glycoprotein. The antibodies did not react with myelin-associated glycoprotein, sulfated glycuronic acid-containing paragloboside (SGPG and SGLPG), or other peripheral nerve glycolipids or gangliosides. To our knowledge this is the first report of strong antibody activity specifically directed against P0. This antibody may play a causative role in the pathogenesis of the peripheral neuropathy in this patient.

Autoantibodies↗
PubMed1992

Molecular cloning and physical mapping of bovine herpesvirus 4 strain DN 599 and comparison with two American field-isolates.

Ninety four percent of the genome of bovine herpesvirus 4 (BHV-4) strain DN 599 was cloned and a physical map was constructed by Southern blot analysis using a library of cloned fragments cleaved with the 3 restriction enzymes (Eco RI, Bam HI, and Hin dIII). The genome length was estimated to be 156.5 kbp +/- 0.7. The genome comprises a region of unique segment (114 kbp) and two flanking segments containing tandem repeats. The size of each repeat was approximately 2.35 kbp and each repeat contained one Eco RI site and two Bam HI sites. We also examined two recent American field-isolates of BHV-4 and compared the Eco RI maps of the two isolates with that of DN 599. We observed the following: (1) insertions or deletions of restriction sites at the periphery of the unique segment; (2) variation in the lengths of junction fragments; (3) variations in the lengths of hypermolar Eco RI fragments containing the repeats; and (4) the Eco RI map of one of the American field-isolates resembles the BHV-4 "Movar type" of Europe.

Animals↗
PubMed1992

Comparison of the N-linked oligosaccharide structures of the two major human myelin glycoproteins MAG and P0: assessment and relative occurrence of oligosaccharide structures by serial lectin affinity chromatography of 14C-glycopeptides.

The N-linked oligosaccharide structures of human myelin-associated glycoprotein (MAG) and P0 have been characterized by serial lectin affinity chromatography (SLAC) of 14C-glycopeptides. 14C-Glycopeptides were prepared from purified MAG derivative and P0 by extensive proteolytic digestion and N-14C-acetylation. Assuming that all the 14C-glycopeptides were radiolabelled to the same specific radioactivity, the relative occurrence of the oligosaccharide structures was correlated to the amount of incorporated radioactivity. Sixteen and 15 fractions were generated by SLAC of MAG and P0 14C-glycopeptides, respectively. Despite this tremendous structural heterogeneity, the oligosaccharide "fingerprints" of MAG and P0 obtained by SLAC displayed similarities: (a) of the three types of N-linked oligosaccharides, the complex type accounted for 80.4% and 94.9% of MAG and P0 radioactivity, respectively; (b) biantennary complex oligosaccharides were the major structures present on MAG and P0; (c) approximately 60% of MAG and P0 oligosaccharides possessed a bisecting N-acetylglucosamine residue; and (d) large amounts of oligosaccharides with an alpha(1-6)fucose residue were found in both MAG and P0 and, noticeably, approximately 25% of the tri- and/or tetraantennary and approximately 90% of the bisected biantennary oligosaccharides of both glycoproteins contained alpha(1-6)fucose residues in the core. This study demonstrates that MAG and P0, both belonging to the immunoglobulin superfamily, display structural similarities in their N-linked oligosaccharide contents.

Carbon Radioisotopes↗
PubMed1992

Comparison of the N-linked oligosaccharide structures of the two major human myelin glycoproteins MAG and P0: assessment of the structures bearing the epitope for HNK-1 and human monoclonal immunoglobulin M found in demyelinating neuropathy.

The epitope for HNK-1 and patient's monoclonal autoantibodies in demyelinating polyneuropathy associated with immunoglobulin M gammopathy is borne by different types of N-linked oligosaccharide structures in human P0 and myelin-associated glycoprotein (MAG). Fourteen glycopeptide fractions bearing different oligosaccharide structures were obtained from either MAG or P0 glycopeptides by serial lectin affinity chromatography on concanavalin A-Sepharose, Phaseolus vulgaris erythrophytohemagglutinin-agarose, Pisum sativum agglutinin-agarose, and Phaseolus vulgaris leucophytohemagglutinin-agarose. As shown by dot-TLC plate immunostaining, the same MAG and P0 glycopeptide fractions were recognized by HNK-1 and patient's immunoglobulin M, confirming that these antibodies display similar specificities. The antigenic carbohydrate was present in glycopeptide fractions that either interact with Pisum sativum agglutinin-agarose or were bound by Aleuria aurantia agglutinin-digoxigenin, indicating that these structures contained alpha(1-6)fucose residues. This study demonstrates that the L2/HNK-1 epitope is borne mainly or even exclusively by N-linked oligosaccharide structures alpha(1-6)fucosylated in the core.

Antibodies, Monoclonal↗
PubMed1992

Carbohydrate moieties of myelin-associated glycoprotein, major glycoprotein of the peripheral nervous system myelin and other myelin glycoproteins potentially involved in cell adhesion.

The myelin-associated glycoprotein (MAG) and the major glycoprotein of the peripheral nervous system myelin (P0) are two members of the family of cell adhesion molecules (CAMs). A role in cell adhesion of the carbohydrate moiety of these molecules has been attributed to the presence of N-glycans bearing the HNK-1 carbohydrate epitope. On the other hand, it has been suggested that these glycoproteins could be ligands of an endogenous mannose-binding lectin present in myelin, the cerebellar soluble lectin (CSL). In order to further document the heterogeneity of the glycans of these two CAMs, we have used several probes: an anti-carbohydrate antibody of the HNK-1 type, called Elec-39, the plant lectin concanavalin A (ConA), and the endogenous lectin CSL involved in myelin compaction. This study shows that CSL binds to a small proportion of the polypeptide chains of MAG found in adult CNS of rats and man and the polypeptide chains of P0 molecules from adult human and rat sciatic nerve. For MAG from adult rat brain, the binding of CSL is restricted to glycans of polypeptide chains which could be separated from the others according to their solubility properties. These MAG molecular entities react also with the Elec-39 antibody and with ConA. These results confirm that P0 and MAG are heterogeneous in their carbohydrate moieties.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Anti-myelin-associated glycoprotein antibodies in patients with a monoclonal IgM gammopathy and polyneuropathy, and a simplified method for the preparation of glycolipid antigens.

The two sulfated glucuronic acid containing glycolipids, sulfate-3-glucuronyl paragloboside (SGPG) and sulfate-3-glucuronyl lactosaminyl paragloboside (SGLPG), were prepared by ion exchange chromatography of lipid extracts from bovine cauda equina. Thin layer chromatography (TLC) immunostaining and an enzyme-linked immunosorbent assay (ELISA) were used to show that the SGPG/SGLPG fraction was free of crossreactive antigenic components such as gangliosides. The results obtained by ELISA demonstrate that sera of all patients were validated IgM monoclonal anti-myelin-associated glycoprotein (MAG) demyelinating neuropathy display high titer antibodies with high affinity type titration curves. These antibodies were absent from the sera of 16 patients with other neurological diseases and ten normal controls. ELISA with SGPG/SGLPG as an antigen appears to be a valuable and highly specific immunodiagnostic test for determining anti-MAG antibody titers in the sera of patients. The amount (approximately 0.4 mg) of SGPG/SGLPG partially purified from 10 g of fresh tissue is sufficient for the preparation of approximately 100 96-well plates for ELISA procedures.

Chromatography, Ion Exchange↗
PubMed1991

Analysis of bovine herpesvirus 4 (DN 599) major antigens with monoclonal antibodies and polyclonal immune serum.

Monoclonal antibodies (MAbs) and polyclonal immune sera were produced and used to identify the major antigens of bovine herpesvirus type 4 (BHV-4). SDS-polyacrylamide gel electrophoresis of immunoprecipitates of radiolabeled lysates from infected cells resolved 24 peptide bands varying from 12 kDa to over 300 kDa. Six peptides were identified as major viral antigens by immunoprecipitation. Based on the pattern of radioimmunoprecipitation, MAbs were assigned into four groups. Group 1 precipitated a tunicamycin-sensitive glycoprotein complex which contained six components (245, 190, 152, 123, and 48/46 kDa). Deglycosylation with endoglycosidase F revealed two peptides with Mr of 93 and 38 kDa as the basic peptides of the glycoprotein complex. In addition, a 115 kDa glycopeptide containing glycan-peptide bonds of mixed type was identified. Group 2 precipitated a non-glycosylated protein complex consisting of three monomers (33/31/30 kDa). Groups 3 and 4 reacted with single monomeric non-glycosylated peptides with Mr of 48 and 14 kDa, respectively. Although none of the MAbs exhibited significant neutralizing activity, some reacted strongly in immunosorbent and/or immunohistochemical assays, suggesting they may be good candidates for use in diagnostic assays.

Animals↗
PubMed1991

Predictive value of anti-GM1 ganglioside antibodies in neuromuscular diseases: a study of 180 sera.

The incidence of anti-GM1 antibodies in the serum of 104 patients with neurological diseases, 35 patients with non-neurological diseases (NND) and 41 normal controls was determined by enzyme-linked immunosorbent assay (ELISA). Anti-GM1 antibodies were found in 90% of patients presenting with a motor neuropathy (all except one had multifocal conduction blocks). A large proportion (60%) of these patients displayed high antibody titer ranging from 101 to 788. A low incidence of anti-GM1 antibodies was found in the other groups of patients, i.e. 21% of amyotrophic lateral sclerosis (ALS), 26% of other neurological diseases (OND) and 23% of NND. High antibody titers ranging from 106 to 260 were found in two (5%) ALS patients, one (2%) OND patient (myasthenia gravis), and one (3%) NND patient (Waldenström's disease). This study shows that high titers of anti-GM1 antibodies are found in a large proportion of patients with motor neuropathy with multifocal conduction blocks. This argues for a possible autoimmune origin of this neuropathy. We suggest that anti-GM1 antibody determination should be included systematically in the evaluation of all patients with motor neuron diseases and predominantly motor neuropathies.

Adult↗
PubMed1991

Characterization of monoclonal antibodies to bovine herpesvirus type I, Los Angeles strain.

We produced monoclonal antibodies (mAbs) against bovine herpesvirus type 1 (BHV-1), Los Angeles strain, and then evaluated them as potential candidates for preparing diagnostic reagents. Of the 318 cell lines expressing antibodies to the virus, 60% (192) secreted IgG and 40% (126) secreted IgM. Twenty-six mAbs were selected based on enzyme-linked immunosorbent assay (ELISA) and virus neutralization (VN) titers and characterized by immunoprecipitation, immunofluorescence and immunoblots. The selected mAbs were assigned to one of four groups based on their immunoprecipitation patterns. Group A (4 mAbs) precipitated a complex of three glycoproteins with molecular weight (MW) 130 kDa, 72 kDa and 55 kDa, which presumably represented gI of BHV-1. Monoclonal antibodies of this group were highly reactive in ELISA but had low VN titers. Group B (4 mAbs) precipitated a glycoprotein with MW of 71 kDa (gIV). This group of mAbs had high VN titers. Group C (16 mAbs) precipitated a 97 kDa glycoprotein (gIII). Monoclonal antibodies of this group had high ELISA but low VN titers. Group D (2 mAbs) precipitated a double band of non-glycosylated proteins with MW of 37/32 kDa; these proteins could not be assigned to any of the antigens of BHV-1 previously described. ELISA and VN titers of this group of mAbs were low. To test the antigenic variability of the antigenic determinants which were recognized by these 4 groups of mAbs, we adapted Madin Darby bovine kidney cell-propagated BHV-1 Los Angeles strain to Crandell's feline kidney cell line. After the tenth passage in feline kidney cells, the epitopes on the 37/32 kDa peptide recognized by the mAbs group D were no longer detectable. Additional changes were noted in the electrophoretic mobility of the 130 kDa and 71 kDa glycoproteins (gI) identified by mAb of group A shifted downward. The 71 kDa glycoprotein (gIV) reactive with mAb group B and the 97 kDa (gIII) reactive with mAb group C remained stable. Since clone No. 191 of group B mAb was potent in ELISA, VN, immunoblots and immunofluorescence, and recognized an epitope which did not change under selective pressure, we feel that the mAb produced by this clone are a good candidate for the production of diagnostic reagents.

Animals↗
PubMed1991

[The blood supply of the cervical esophagus].

In accordance with former authors the arteries for the cervical esophagus originate mainly from the inferior thyroid artery. In a few cases additional vessels originated directly from the subclavian artery. After a variable course they approach the esophagus in a purely transverse direction. The uppermost vessels originating from the inferior thyroid artery may send branches to the posterior wall of the trachea and also supply the anterior wall of the esophagus. The surgical separation of the two organs is dangerous for the esophagus.

Esophagus↗