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H J Gabius

Publications and source records attributed to H J Gabius.

At least 199 records · Page 11Linked to original sources
PubMed1993

Isolation and biochemical characterization of heparin-binding proteins from boar seminal plasma: a dual role for spermadhesins in fertilization.

Sperm surface-coated heparin-binding proteins originating from secretions of the male sexual accessory glands, are known to play a pivotal role as extrinsic regulatory factors during sperm capacitation in many mammalian species. They interact with glycosaminoglycans present in the female genital tract and enhance the subsequent zona pellucida-induced acrosome reaction. We have isolated heparin-binding proteins from boar seminal plasma by affinity chromatography on heparin-Sepharose and reverse-phase HPLC. N-Terminal sequence analysis of these proteins identified a boar counterpart of the bovine capacitation factors BSP-A1/2 (also called PDC-109) and BSP-A3. Several carbohydrate- and zona pellucida-binding proteins, which belong to the newly described spermadhesin family, were also identified as heparin-binding proteins. Our results imply that, besides other capacitation factors, members of the spermadhesin family may play a dual role in sperm capacitation and fertilization in the pig.

Amino Acid Sequence↗
PubMed1993

Detection of endogenous receptors for carbohydrate ligands in primary and metastatic human renal cell carcinoma.

Frozen sections of primary and metastatic human renal cell carcinoma (RCC) were analyzed for the expression of endogenous binding sites for carbohydrates. Fluorescent neoglycoproteins, carrying chemically linked carbohydrate residues on bovine serum albumin as a carrier protein, were applied to 44 primary tumor specimens. In the majority of specimens, accessible binding sites with specificity for maltose and N-acetylgalactosamine were detected. In specimens of normal kidney no specific binding of carbohydrate ligands was observed under these experimental conditions. Specimens of both the primary tumor and a metastasis were available in 10 cases. When the expression of specific binding sites of primary tumors and metastases was compared, the respective patterns were similar with no clear gain or loss of certain lectins in the metastases. We conclude that binding sites with specificity for maltose and N-acetylgalactosamine are present on human RCC and their corresponding metastases.

Acetylgalactosamine↗
PubMed1993

Identification of annexin II, annexin VI and glyceraldehyde-3-phosphate dehydrogenase as calcyclin-binding proteins in bovine heart.

1. Matrix-immobilized calcyclin as affinity ligand in chromatography led to purification of three protein bands at 68, 36 and 35 kDa from bovine heart that required Ca2+ for binding. 2. Polyacrylamide-immobilized phosphatidylserine separated this fraction into a phospholipid-binding part (68 kDa, 35 kDa), also attaching to phospholipid vesicles even in the presence of calcyclin, and a flow-through part, constituting approx 30% of the total fraction (36 kDa). 3. Enzyme assays and electrophoretic mobility showed an at least close relationship of the 36 kDa band to glyceraldehyde-3-phosphate dehydrogenase. Interaction between enzyme and calcyclin in a solid-phase assay was inhibited by sialoglycoproteins and depended strongly on the integrity of carboxyl and hydrophobic groups of the enzyme. The interaction between the two proteins had a KD value of 110 nM. 4. Application of annexin-specific antibodies revealed an immunological relationship of the 35 and 68 kDa calcyclin-binding proteins to members of the annexin family, namely to annexin II (35 kDa) and annexin VI (68 kDa). The N-terminal amino acid sequence of a cleavage peptide of the 68 kDa protein was identical to a sequence stretch in human annexin VI, corroborating this evidence.

Amino Acid Sequence↗
PubMed1993

Detection of the lymphokine migration inhibitory factor in normal and disease-affected lung by antibody and by its major binding protein, the interferon antagonist sarcolectin.

Human migration inhibitory factor (MIF) is suggested to play a notable role in regulation of macrophage functions in host defense. A major binding component for the lymphokine in human tissue is the interferon antagonist sarcolectin. This high-affinity interaction gives access to MIF by affinity chromatography on immobilized sarcolectin and may be of significance for in situ activity of MIF. Localization of MIF is one step towards answering this question. Labelled sarcolectin and MIF-specific antibodies can be employed to analyze the expression of the factor. Surgical specimens of 74 patients, who underwent lobe/lung resection or diagnostic biopsy, were fixed with buffered formalin and embedded in paraffin. The material consisted of 36 cases of morphologically normal lung parenchyma of patients, suffering from bronchial carcinoma, of 16 cases with sarcoidosis, of 15 cases with tuberculosis and of 7 cases with idiopathic interstitial pneumonitis. The two types of probe to visualize presence of MIF invariably showed the same level of reactivity, underscoring the potential physiological significance of sarcolectin-MIF interaction. In detail, all cases with pneumonitis, most tuberculosis-affected as well as normal cases and 44% of the cases with sarcoidosis were positive. All positive cases with sarcoidosis and some cases from the other groups revealed accessible binding sites for biotinylated MIF.

Binding Sites↗
PubMed1993

Inhibition of the adenylylation of liver plasma membrane-bound proteins by plant and mammalian lectins.

Liver plasma membrane contains four major (130-kDa, 120-kDa, 110-kDa and 100-kDa) sialic acid-containing glycopolypeptides that are able to undergo adenylylation, as well as phosphorylation (San José et al. (1990) J. Biol. Chem. 265; 20653-20661). To gain insight into the regulation of these processes, lectins are employed to probe the extent of influence of their interaction with membrane fractions for these reactions. We demonstrate that the beta-galactoside-specific lectins from bovine heart and mistletoe at low concentrations inhibit the adenylylation of this set of plasma membrane glycopolypeptides. The extent of phosphorylation of these polypeptides is also reduced although to a lesser degree. Concanavalin A, too, inhibits the adenylylation of the plasma membrane glycopolypeptides, although higher concentrations of this lectin were required, whereas wheat germ lectin has only a very small inhibitory effect. The adenylylable polypeptides were isolated by concanavalin A-agarose chromatography upon elution with mannose. In agreement with this result, control experiments with a panel of neoglycoproteins indicate that mannose residues appear to be required for the concanavalin A-induced inhibition of the adenylylation. Neoglycoproteins containing mannose 6-phosphate, lactose, fucose, or sialic acid instead of mannose lack the ability to protect the adenylylation from the inhibitory action of concanavalin A. In contrast, none of the above-mentioned neoglycoproteins, nor asialofetuin, nor galactose-containing saccharides protect the adenylylation against the inhibitory effect of both the mistletoe and bovine heart lectins, emphasizing the importance of either high affinity carbohydrate ligands in the overall process, or other ligand sites for the lectins beside carbohydrates to affect the regulation of the adenylylation system.

Adenine↗
PubMed1993

Efficient induction of superoxide release from human neutrophils by the galactoside-specific lectin from Viscum album.

The immunomodulatory galactoside-specific lectin from Viscum album (VAA) induces superoxide anion (O2.-) release from human neutrophils. Among twelve tested lectins, VAA, has the highest activity, clearly surpassing the effect of the human beta-galactoside-specific lectin (galaptin). Its reactivity is blocked in the presence of lactose and is strictly dependent on the carbohydrate-binding B-subunit. The toxic A-subunit of the lectin does not elicit a response. The VAA-induced respiratory burst is less sensitive to addition of adenosine and theophylline than the concanavalin A-mediated reaction. Other modulators like amiloride (up to 100 microM), trifluoperazine and N-ethylmaleimide reveal less pronounced differences, and indomethacin, colchicine (up to 100 microM) as well as cytochalasin B act as stimulators of lectin-induced O2.- release from neutrophils. The O2.- production in the presence of small concentrations of VAA (0.1-20 micrograms/ml) is increased by addition of N-formylmethionyl-leucyl-phenylalanine (FMLP), phorbol 12-myristate 13-acetate (PMA) or digitonin, respectively, whereas concanavalin A (Con A) or wheat germ agglutinin (WGA) fail to affect the VAA-dependent extent of the respiratory burst. These results substantiate that the VAA-induced O2.- release from human neutrophils can be enhanced by other classes of inductors.

Adenosine↗
PubMed1993

Gel-immobilized heparin-binding lectin as sensitive sensor for certain groups of charge-bearing carbohydrates.

The specificity of lectins to carbohydrate moieties in principle enables them to serve as sensors for sugars with ligand properties. However, experimental systems and parameters to measure this interaction need to be defined. On the basis of knowledge about temperature-sensitive volume changes of gels, composed of acrylamide derivatives, and about the influence of presence of charge-bearing groups within the gel on this behavior, we covalently immobilized a human heparin-binding lectin into a gel matrix. Besides the lectin-carrying derivative N-isopropylacrylamide and N,N'-methylenebisacrylamide are the monomeric constituents of the polymer. The lectin has been attached to divinyl sulfone-activated N-hydroxymethylacrylamide. Several anionic sugar moieties are added to the solution, covering the gel pieces, and the mechanical response of the individual gel slices in dependence to stepwise temperature increases is automatically recorded with an electronic transducer at a sensitivity of 5 mV/microns. Only carboxyl group-containing sugar moieties like glucuronic acid notably reduce the extent of the temperature-dependent gel shrinking as indicator for a protein-carbohydrate interaction. The individual slices are reuseable, emphasizing practical applications. This sensitive and automated assay concept with the covalently immobilized heparin-binding protein is supposed to be adaptable to other groups of lectins with specificity to anionic sugars like sialic acid-binding proteins.

Acrylamides↗
PubMed1993

Atherosclerosis-associated changes in the carbohydrate-binding capacities of smooth muscle cells of various human arteries.

A set of labelled neoglycoproteins and sulfated polysaccharides, recognizing carbohydrate receptors specific for glucose (glu), mannose (man), lactose (lac), fucose (fuc), fucoidan (fud), dextran sulfate (dex), and heparin (hep), as well as polyclonal antibodies specific for an endogenous beta-galactoside-specific lectin of molecular weight 14kD (A14kD) and a heparin-binding lectin (AHL) have been applied to the main arteries of 10 autopsy cases. Slides of the following types of vessels were incubated with solutions of the biotinylated probes or antibodies at room temperature for 60 min: right and left coronary artery, carotid artery, abdominal and thoracic aorta, pulmonal artery, and the left femoral artery. Atherosclerotic lesions and non-atherosclerotic areas were analyzed for each individual type of vessel. The percentage of the determined expression of the presence of specific binding sites for the various probes was the lowest in the carotid and cardiac arteries, and the highest in the pulmonal artery. Pronounced quantitative differences between the normal and atherosclerotic arterial walls were noted for binding of fuc-, man-, and lac-exposing neoglyco-proteins of the right coronary artery and the carotid artery. Pulmonal and femoral arteries differed with respect to fucoidan or dextran sulfate binding. The heparin-specific lectin and the 14kD-lectin were found to be present in nearly all arterial walls, independent from the localization and the presence of an atherosclerotic lesion. The findings suggest that the expression of sugar receptors, as assessed by labelled neoglycoproteins or sulfated polysaccharides, may be of importance in the development of atherosclerotic lesions in the coronary and carotid arteries.

Aged↗
PubMed1993

Alteration of human lung parenchyma associated with primary biliary cirrhosis.

The clinical history, radiological and histomorphological alterations of the lung parenchyma in a patient suffering from primary biliary cirrhosis are described. The 70-year-old woman had developed a primary biliary cirrhosis, verified by serological abnormalities (AMA positivity, elevated IgM levels) and by liver biopsy. The lung parenchyma displayed immature epithelioid granulomas and characteristics of a chronic organizing pneumonia. Lung function revealed moderate restrictive changes; chest radiographs revealed bilateral, diffuse, patchy infiltrates in the basal lobes. Application of immunohistology detected antigens in liver cells reactive with anti-IgD and anti-IgG, in pneumocytes those reactive with anti-IgD. Presence of macrophage migration inhibitory factor (MIF) by application of its antibody and of the ligand sarcolectin as well as expression of binding capacities to MIF could not be demonstrated in the liver and lung parenchyma. Neoglycoproteins exposing fucose, N-acetyl-D-glucosamine, lactose and mannose residues did not bind to both the liver and lung tissue. The data indicate that at least some patients with primary biliary cirrhosis may develop or suffer from immunological abnormalities, affecting the lung.

Aged↗
PubMed1993

Histochemical analysis of carbohydrate moieties and sugar-specific acceptors in the kidneys of the laboratory mouse and the golden spiny mouse (Acomys russatus).

The aims of this work were to histochemically compare the pattern of lectin binding and endolectin expression in different portions of nephrons of two rodent species producing either normal hyperosmotic urine (the laboratory mouse) or highly concentrated urine (Acomys russatus, the golden spiny mouse). A panel of biotinylated lectins and neoglycoproteins and the avidin-biotin-peroxidase complex technique were used on Bouin's fixed, paraffin-embedded sections. Various segments of the uriniferous tubule in both species showed differential affinity for labelled lectins and neoglycoproteins. Significant differences were also evident between comparable tubular segments in laboratory and golden spiny mouse kidneys. Whether the histochemical expression of sugar moieties of glycoconjugates as well as endolectins, thus both sides of presumed protein-carbohydrate interactions, may be correlated to the various glycoproteins which would include constituents of the glycocalyx and domains of a variety of transport enzymes deserves further studies.

Animals↗
PubMed1993

Malignant teratoma of the lung with lymph node metastasis of the ectodermal compartment: a case report.

A rare case with a metastasizing teratocarcinoma of the lung is presented. The 51-year-old man developed a central tumour mass in the left lung. Bronchoscopy and intraoperative sections of an involved lymph node supplied histomorphologic findings that are indicative for an epidermoid carcinoma. Further detailed analysis resulted in the final classification as a malignant teratoma. This rare tumour was further analyzed for the expression of various cellular characteristics, namely binding sites for various carbohydrates including sequences such as saccharides of the ganglioside GM1, for erythropoietin, tumour necrosis factor-alpha, and epidermal growth factor. Immunohistochemistry was used to determine the expression of neuron-specific enolase, carcino-embryonic antigen, calcyclin, epidermal growth factor, beta-HCG, AFP, p53 protein, and heparin-specific lectin. The results revealed similarities to a case with a pulmonary blastoma, and remarkable differences to that of epidermoid carcinoma cases. Similar results were seen in the DNA- and syntactic-structure analysis. The tumour reported on here should, therefore, be considered as a rare, specific entity of primary lung malignancies.

Carcinoma, Squamous Cell↗
PubMed1993

Reverse lectin histochemistry: design and application of glycoligands for detection of cell and tissue lectins.

Plant and invertebrate lectins are valuable cyto- and histological tools for the localization of defined carbohydrate determinants. The well-documented ubiquitous occurrence of sugar receptors encourages functional considerations. Undoubtedly, analysis of the presence of vertebrate lectins in tissues and cells is required to answer the pertinent and tempting question on the physiological relevance of protein (lectin)-carbohydrate recognition in situ. Carrier-immobilized glycoligands, derived from custom-made chemical synthesis, enable the visualization of respective binding sites. Histochemically inert proteins or synthetic polymers with appropriate functional groups are suitable carrier molecules for essential incorporation of ligand and label. The resulting neoglycoconjugates can track down tissue receptors that are neither impaired by fixation procedures nor blocked by endogenous high-affinity ligands. Lectins, especially the receptors of the tissue under investigation (endogenous lectins), and appropriately tailored immobilized glycoligands or lectin-specific antibodies (when available) are complementary tools to test the attractive hypothesis that diverse, functionally relevant glycobiological processes within or between cells are operative. Concomitant evaluation of both sides of lectin histochemistry, namely lectins as tools and lectins as functionally important molecules in situ, will indubitably render desired progress amenable in our often still fragmentary understanding of the importance of tissue lectin and glycoconjugate expression and its regulation.

Animals↗
PubMed1992

Ligand binding characteristics of the major mistletoe lectin.

Carbohydrate binding specificity of the galactose-specific, major lectin of mistletoe extract (ML-1) was studied by an inhibition assay using monosaccharides, monosaccharide derivatives, disaccharides, and compounds containing multiple galactosyl terminals. The results indicate that 1) both alpha- and beta-galactosyl residues are recognized equally well; 2) each of the hydroxyl groups of galactose contributes to varying degrees to the binding process, the 4-OH being the most important and the 6-OH the least important hydroxyl group; 3) disaccharide sequences of Gal beta 2Gal and Gal beta 3Gal have much higher affinity than galactose, whereas affinity of all other Gal-disaccharides is only slightly better than galactose; 4) macromolecular ligands having 10 or more terminal galactosyl residues have 500-fold higher affinity than Gal; and 5) a group on ML-1 with pK alpha of 4.8 appears to be involved in the binding of ligand.

Binding Sites↗
PubMed1992

Behavior of lymphocyte subsets and expression of activation markers in response to immunotherapy with galactoside-specific lectin from mistletoe in breast cancer patients.

Cellular aspects of the immunomodulating activity of the galactoside-specific lectin from mistletoe (ML-1) were investigated in 10 cancer patients. Regular subcutaneous injections (4 weeks) of the optimal dosis of ML-1 (1 ng per kg body weight, twice a week) yielded notable increases in the apparent numbers of certain lymphocyte subsets [pan T cells; helper T cells; natural killer (NK) cells] which are generally believed to be involved in antitumor immunity. Moreover, ML-1 administration resulted in an increased level of expression of interleukin (IL)2 receptors on lymphatic cells, an indicator of cellular activation. In vitro, the exposure of human lymphocytes to ML-1 resulted in an enhanced expression of receptors for IL-2 (T cells) and HLA-DQ (B cells), which similarly substantiated the capacity of ML-1 to affect immunological parameters within the host defense system. Thorough clinical trials are now required to assess any impact of the application of the lectin on the course of the disease.

Biomarkers↗
PubMed1992

Detection and quantitation of cell-surface sugar receptor(s) of Leishmania donovani by application of neoglycoenzymes.

Promastigote culture forms of the log growth phase of Leishmania donovani stock LRC L 51 were investigated for expression of cell-surface carbohydrate-binding sites using 15 types of a chemically glycosylated enzyme termed neoglycoenzyme. Carbohydrate conjugation and coupling yield were kept constant to ensure that the type of carbohydrate moiety was the only variable feature of the applied tools. Para-aminophenyl derivatives of the following carbohydrate residues were used for the glycosylation of beta-galactosidase from Escherichia coli: beta-D-lactose, beta-D-thiogalactose, alpha-D-mannose, alpha-L-rhamnose, alpha-D-N-acetylgalactosamine, beta-D-N-acetylgalactosamine, beta-D-N-acetylglucosamine, the alpha- and beta-glucosides maltose and cellobiose, beta-D-xylose, alpha-D-mannose-6-phosphate, the alpha-galactoside melibiose, alpha-L-fucose, and beta-D-glucuronic acid as well as sialic acid. Only melibiose, fucose, and glucuronic acid showed no binding affinity for the cultured flagellates; this served as an internal control reaction to exclude any binding to the linker group. This result demonstrates that many but not all sugar types can be recognized by appropriate receptor structure(s) on the surface of the promastigote Leishmania. Transformation of the binding data for neoglycoenzymes exposing lactose, mannose, rhamnose, and N-acetylated hexose residues, which was carried out to obtain the dissociation constants and to estimate the number of binding sites at saturation, revealed KD values of around 100 mM and around 10(4) binding sites for the polyvalent ligands.

Animals↗
PubMed1992

Analysis of tumour necrosis factor alpha-specific, lactose-specific and mistletoe lectin-specific binding sites in human lung carcinomas by labelled ligands.

Receptor sites can be visualized by labelled ligands as an alternative to receptor-specific antibodies, as substantiated for two different receptor classes. Recombinant tumour necrosis factor alpha (TNF) was biotinylated via amino-groups and the resultant probe was applied to formalin-fixed, paraffin-embedded tissue sections of 94 primary bronchial carcinomas and to normal peripheral lung parenchyma. In addition, monoclonal antibodies specific for neuron-specific enolase (NSE) and TNF itself were used. The biotinylated beta-galactoside-specific mistletoe lectin, which exhibits dose-dependent immunomodulatory and toxic potency, and two probes that specifically detect certain types of sugar receptors were employed to illustrate further the feasibility of using ligands for receptor localisation. The tumours comprised 62 small cell lung carcinomas, 10 epidermoid carcinomas, 11 adenocarcinomas and 11 large cell anaplastic carcinomas. Expression of TNF-binding sites was found in 39 of the small cell lung carcinomas and in 13 of the non-small cell lung carcinomas. Binding capacity for the TNF-specific antibody was seen in similar proportions of small cell lung carcinomas and of non-small cell lung carcinomas. None of the normal lung parenchymas revealed significant staining. Binding capacities to mistletoe lectin were seen in all normal lung parenchymas and in nearly all cases of adenocarcinoma (10/11). A correlation between the expression of NSE and the binding capacities to TNF was detected. Endogenous lectins, specific for lactose or beta-GalNAc, were displayed in nearly one half of the small cell lung carcinoma cases (44% or 45% respectively) and in about 25% of the non-small cell lung carcinoma cases.

Acetylgalactosamine↗
PubMed1992

Changes of expression of endogenous sugar receptors by polymorphonuclear leukocytes after prolonged anaesthesia and surgery.

Anaesthesia and surgery are known to depress granulocyte function in the early postoperative period, leading to deterioration of the immune defence against infection. Carbohydrate-lectin interactions may play an important role in the activities of phagocytic cells in that they facilitate initial host defence in the event of microbial antigenic challenge. A panel of biotinylated (neo)glycoproteins (chemically glycosilated carrier proteins) was used to detect endogenous carbohydrate-binding receptors /lectins/, on peripheral blood polymorphonuclear leukocytes of patients undergoing prolonged anaesthesia for replantation surgery. Four hours after induction of anaesthesia, a progressive decline of expression of endogenous sugar receptors on granulocytes was detected using the labelled (neo)glycoproteins lactose-BSA, N-acetyl-D-glucosamine-BSA, D-mannose-BSA, sialic-acid-BSA and D-xylose-BSA. Concomitant changes in peripheral white blood cell counts and the lack of depression in the absence of general anaesthetic agents suggested the existence of a possible relationship between reduced expression of (neo)glycoprotein receptors to impaired granulocyte function and anaesthetic-induced immunodepression.

Acetylglucosamine↗