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H Wiegandt

Publications and source records attributed to H Wiegandt.

At least 19 recordsLinked to original sources

Glycoinositolphosphosphingolipids (basidiolipids) of higher mushrooms.

The basidiolipids of six mushroom species, i.e. the basidiomycetes Amanita virosa (engl., death cup), Calvatia exipuliformis (engl., puffball), Cantharellus cibarius (engl., chanterelle), Leccinum scabrum (engl., red birch boletus), Lentinus edodes (jap., Shiitake), and Pleurotus ostreatus (engl., oystermushroom), were isolated, and their chemical structures investigated. All glycolipids are structurally related to those of the Agaricales (engl., field mushroom). They are glycoinositolphosphosphingolipids, their ceramide moiety consisting of t18:0-trihydroxysphinganine and an alpha-hydroxy long-chain fatty acid. In contrast to a previous study [Jennemann, R., Bauer, B.L., Bertalanffy, H., Geyer, R., Gschwind, R.M., Selmer, T. & Wiegandt, H. (1999) Eur. J. Biochem. 259, 331--338], the glycoside anomery of the hexose (mannose) connected to the inositol of all investigated basidiomycete glycolipids, including the basidiolipids of Agaricus bisporus, was determined unequivocally to be alpha. Therefore, the root structure of all basidiolipids consists of alpha-DManp-2Ins1-[PO(4)]-Cer. In addition, for some mushroom species, the occurrence of an inositol substitution position variant, alpha-Manp-4Ins1-[PO(40]-Cer, is shown. The carbohydrate of chanterelle basidiolipids consists solely of mannose, i.e. Cc1, Man alpha-3 or -6Man alpha; Cc2, Man alpha-3(Man alpha-6)Man alpha-. All other species investigated show extension of the alpha-mannoside in the 6-position by beta-galactoside, which, in some instances, is alpha-fucosylated in 2-position (Fuc alpha-2)Gal beta-6Man alpha-. Further sugar chain elongation at the beta-galactoside may be in 3- and/or 6-position by alpha-galactoside, e.g. Ce4, Po2, Gal alpha-3-(Gal alpha-6)(Fuc alpha-2)Gal beta-6Man alpha-, whereas A. virosa, Av-3, has a more complex, highly alpha-fucosylated terminus, Gal alpha-3 (Fuc alpha-2)(Fuc alpha-6)Gal alpha-2(Gal alpha-3)Gal beta-6Man alpha-. L. edodes basidiolipids show further elongation by alpha-mannoside, e.g. Le3, Man alpha-2Man alpha-6Gal alpha-3(Fuc alpha-2)Gal beta-6Man alpha-, C. exipuliformis glycolipid by alpha-glucoside, i.e. Ce3, Glc alpha-6Gal beta-6Man alpha-. Basidiolipid Ls1 from L. scabrum, notably, has a 3-alpha-mannosylated alpha-fucose, i.e. Gal alpha-6(Man alpha-3Fuc alpha-2)Gal alpha-6Gal beta-6Man alpha-. In conclusion, basidiolipids, though identical in their ceramide constitution, display wide and systematic mushroom species dependent variabilities of their chemical structures.

Agaricales↗

Human heterophile antibodies recognizing distinct carbohydrate epitopes on basidiolipids from different mushrooms.

Investigating the immune properties of basidiolipids, i.e., glycoinositolphosphoceramides (GIPC) of basidiomytes, higher mushrooms, it was detected that sera of normal adult human subjects contained IgG2 and IgM heterophile antibodies (hetAbs) that immunoreacted with these lipids. However, this immune recognition was not shared by the glycolipids of all mushroom species. The basidiolipids of Amanita virosa (eng., death cup) and Cantharellus cibarius (engl., chantarelle), of all mushroom species studied, did not bind antibodies of normal human sera. In addition, only certain basidiolipids of the other mushroom species that have been investigated, i.e., Agaricus bisporus (engl., field mushroom), Calvatia exipuliformis engl., puffball), Lentinus edodes (jap., Shiitake), Leccinum scabrum (engl., red birch boletus), and Pleurotus ostreatus (engl., oyster mushroom), immunoreacted with the human hetAbs. The basidiolipids that were recognized by the human hetAbs had either terminal Galalpha1-6Gal < or Galbeta1-6Man< epitopes. Enzymatic destruction of the respective carbohydrate epitopes abolished the previous immune reactivity. It is assumed that contact with non human antigens causes generation of the anti-basidiolipid antibodies.

Adult↗

Regional expression of sulfatides in rat kidney: immunohistochemical staining by use of monospecific polyclonal antibodies.

Sulfatides are quantitatively prominent glycosphingolipids of rat kidney. In order to gain insight into their possible physiological significance in this organ, and their possible role in Heymann's nephritis, the main sulfatide components were localized immunohistochemically. The antibodies used recognized the sulfatides Sgal1, Stri1, Stri2, and Stet2a. Stri1 epitopes were expressed in the brush border of proximal tubuli, whereas Stri2-specific immuno staining was observed in cortical and medullar collecting ducts. Both Stri1 and Stri2 were also expressed by interstitial cells of the inner medulla. Stet2a was visualized in epithelia of the distal tubules of Henle's loop and the juxtaglomerular apparatus, including the macula densa. The mAb Sulph-I, that recognizes the SO3(-)-3Galbeta<epitope of Sgal1, seminolipid, and Slac1, prominently stained the cortical and medullar collecting ducts. No sulfatide was immuno-stained in the glomerular region. For this reason, the possibility of a direct involvement of anti-Stri1 and Stri2 antibodies in the etiology of Heymann's nephritis appears to be less likely. A strict correlation between the local sulfatide content, as analyzed by chemical estimation, and the sulfatide expression, as observed by immunohistochemical methods, may not be possible.

Animals↗

Basidiolipids from Agaricus are novel immune adjuvants.

The primary aim of the present study was to compare the immune adjuvanticity of two different groups of glycolipids, i.e., the newly discovered basidiolipids from Basidiomycete mushrooms (Bl-1, Bl-2, Bl-3, and Bl-4), and saponin fractions from Quillaja saponaria. The basidiolipids, though with differential effectiveness of the Bl-components, stimulated the expression of serum immune globulins in mice that recognized co-injected antigens, bovine serum albumin (BSA) or a keyhole-limpet hemocyanin-ganglioside Gfpt1 conjugate (KLH-Gfpt1), respectively. The immune adjuvanticity of the basidiolipids was comparable to that of acidic (QAS2, QAS5, QAS10), and novel neutral (QNS1, QNS2, QNS3) saponin compounds isolated and purified from Quillaja saponaria bark bulk material. Basidiolipids, as well as, the Q. saponin fractions were only marginally antigenic. MPL-A, by contrast, a comparable immune adjuvant, stimulated the expression of specific antibodies that recognized this glycophospholipid. Different from the Q. saponins with restricted toxicity, the basidiolipids displayed no toxic or hemolytic properties.

Adjuvants, Immunologic↗

Novel glycoinositolphosphosphingolipids, basidiolipids, from Agaricus.

From the edible mushroom, the basidiomycetes Agaricus bisporus and Agaricus campestris, a novel carbohydrate-homologous series of four glyco-inositol-phospho-sphingolipids, designated basidiolipids, was isolated and the constituents purified. The chemical structures of the basidiolipids were elucidated to be: Manpbeta1-2inositol1-phospho-ceramide, Galpalpha-6[Fucpalpha-2]Galpbeta-6Manpbeta-2i nositol1-phospho-ceramide, Galpalpha-6Galpalpha-6[Fucpalpha-2]Galpbeta- 6Manpbeta-2inositol1-phospho-ceramide and Galpalpha-6Galpalpha-6Galpalpha-6[Fucpalpha-2] Galpbeta-6Manpbeta-2ino sitol1-phospho-ceramide. All four glycolipids contained a ceramide which was composed of phytosphingosine and predominantly alpha-hydroxy-behenic and alpha-hydroxy-lignoceric acid.

Adjuvants, Immunologic↗

The degradation of glycosphingolipids by air.

Exposure of glycosphingolipids to air irreversibly destroys the integrity of these lipids within a few hours. It was established that among the natural constituents of air, ozone, at commonly observed daytime levels, is responsible for the observed degradation. As one product of the reaction of glycosphingolipids with air, an aldehydic fragment containing the carbohydrate moiety was identified. This aldehydic fragment was identical to the one obtained by classical glycosphingolipid ozonolysis. Identical with the latter, the air-induced product is further fragmented by mild alkali treatment with concomitant liberation of the free reducing oligosaccharide. As a consequence of the alteration of glycosphingolipids by air, it was shown that the accuracy of methods of analysis of these glycoconjugates that depend on their physico-chemical integrity, e.g., by tlc-immune overlay, is severely influenced by their prior exposure to the atmosphere.

Air↗

Effects of monophosphoryllipid-A on the immunization of mice with keyhole limpet hemocyanin- and muramyldipeptide-ganglioside Gfpt1 conjugates.

Since it was considered that an active immunization against ganglioside Gfpt1 (IV2Fuc-, II3NeuAc-Gg4Cer) expressed by human small cell lung cancer cells may be beneficial in the treatment of this neoplasm in humans, an optimal mode of vaccination in model mice was investigated. A novel Gfpt1-muramyldipeptide conjugate (Gfpt1-MDP) was synthesized. Its ganglioside carbohydrate-directed immunogenicity in mice as measured by serum antibody titers was comparable to that of the previously described Gfpt1-keyhole limpet hemocyanin conjugate (Gfpt1-KLH). Similar immunogenicity was displayed by free Gfpt1 in muramyldipeptide-phosphoethanolamine-containing phosphatidyl-choline, -serine (PC,PS) liposomes. Immunization with Gfpt1-vaccines in the presence of monophosphoryllipid A (MPL), in general, raised titers of anti-Gfpt1 antibodies effectively. Immunization with PC, PS-liposomes containing unconjugated Gfpt1 and MPL stimulated the highest titers observed, thereby effectively preventing tumor growth in Balbc nu/nu-mice challenged with human small cell lung cancer cells. However, there was a strong crossreaction of these and most other sera with the structurally related and widely distributed ganglioside Gtet1 (II3NeuAc-Gg4Cer). Only immunization with Gfpt1-KLH conjugate in the presence of MPL stimulated selectively high anti-Gfpt1 antibody titers showing comparably low crossreactivity to ganglioside Gtet1.

Adjuvants, Immunologic↗

The chemical constitution of gangliosides of the vertebrate nervous system.

Glycosphingolipids are uniquely distinguished amongst the glycoconjugates by the apparently systematic structuring of their ceramide-linked carbohydrate moieties. These often highly complex oligosaccharides provide a structural repertoire that may vary considerably according to cell types and animal species. However, as a possible reflection of their specific functional role in the central nervous system, the brain glycosphingolipids of all vertebrates follow the same principles of carbohydrate structuring with only minor variations: the anabolically early addition of sialic acid to lactosylceramide (Gal beta 4Glc beta Cer-->NeuAc alpha 3Gal beta 4Glc beta Cer) in central nervous tissue results in the preferential formation of 'gangliosides', i.e., sialic acid-containing glycosphingolipids. Higher gangliosides result from extensions of sialo-lactosylceramide by addition of nucleotide-activated monosaccharides. In consequence, gangliosides of the vertebrate central nervous system consist of ceramide-linked sialo-oligosaccharides of varying chain length with a ganglio-series core carbohydrate, i.e., GalNAc beta 4Gal beta 3GalNAc beta 4Gal beta 4Glc beta < 0. Substitution by mono-, bis-, or tris-sialo-groups may variably be at the galactoside- and N-acetylgalactosaminide residues in 3- and 6-positions of the ganglio-series oligosaccharides, respectively. Ganglioside, which is derived by sialylation of galactosylceramide, NeuAc alpha 3Gal beta Cer, is a characteristic constituent of glial cells. In nerve tissue, gangliosides of the lacto-(Gal beta(3GlcNAc beta 3Gal beta)n4Glc beta <) and the neolacto-series (Gal beta(4GlcNAc beta 3Gal beta)n4Glc <) are more characteristic of vertebrate peripheral nerves and neuroectoderm-derived tumours. Recent studies using monoclonal antibodies have revealed that various single ganglioside components are specifically distributed in nervous tissues. This finding adds a new dimension to the earlier notion that gangliosides are involved in membrane related phenomena including cell to cell interactions, as well as, the modulation of signalling mechanisms.

Animals↗

Re-assessment of acidic glycosphingolipids in small-cell-lung-cancer tissues and cell lines.

The occurrence of tumor-associated glycosphingolipids (GSLs) has been documented in a variety of cancer tissues (Hakomori, 1984, 1985, 1989). In the case of small-cell lung cancer (SCLC), the monosialoganglioside IV2Fuc-II3NeuAc-Gg4Cer (Fuc-GM1; short notations of gangliosides are according to Svennerholm, 1963), first described from bovine liver (Wiegandt, 1973), was found to be a unique tumor-associated GSL (Nilsson et al., 1984). It is present in up to 90% of all SCLC cases as compared with 25% frequency in non-SCLC, and no occurrence in normal lung (Brezicka et al., 1989, 1992). Thus, Fuc-GM1 may represent a suitable target antigen for immunotherapy of SCLC, and successful experiments have been performed showing tumor-cell killing by monoclonal antibodies (MAbs) against Fuc-GM1, both in vitro and, in a mouse model, in vivo (Brezicka et al., 1991). However, an effective tumor vaccination in humans would require this antigen to be expressed by the primary tumor and also by all metastases. The co-expression of Fuc-GM1 has already been reported in primary tumors and in most but not all metastases of SCLC (Hanquing et al., 1986; Nilsson et al., 1986; Brezicka et al., 1989). In view of the significance this ganglioside may have for possible immunotherapeutical approaches to SCLC and of the difficulty in obtaining a sufficient number of samples for analysis, a re-assessment of Fuc-GM1 expression was made in SCLC primary tumors and their metastases, as well as in established SCLC cell lines. In addition, the possible presence of such gangliosides, that might help to explain the selective tetanus-toxin binding of SCLC cells (Critchley et al., 1986; Heymanns et al., 1989) was investigated. Finally, the typical occurrence of sulfatide in all SCLC tissues and cell lines could be established.

Animals↗

Glycosphingolipid component profiles of human gliomas correlate with histological tumour types: analysis of inter-individual and tumour-regional distribution.

Three types of glycosphingolipid (GSL) component profiles have been established for human intracranial gliomas. GSL-type I shows only Glac- and lacto-series-sialoglycolipids. Type II consist of Glac- and Gtri-gangliosides, whereas only GSL-type III contains sulphatide and, as a major neutral glycolipid, galactocerebroside, besides gangliosides of the Glac-, Gtri-, and Gtet-families. Whole gliomas of malignancy grading I/II, III and IV, display GSL-Types III, II, and I, respectively. Thus, the GSL component distribution of the samples taken after surgery from three individual gliomas and two biopsies correlate closely with the general diagnosis of these tumours. Arthrobacter ureafaciens sialidase was used for the characterization of gangliosides. GSL-type analysis of multiple regional samples, taken from necropsy and biopsy, were determined by microanalysis of microscopic cryostat section, and shown to be in good agreement with their histology. The results validate the relevance of tumour ganglioside analysis for the characterization and diagnosis of gliomas.

Biomarkers, Tumor↗

A rapid method for the preparation of ganglioside Glac2 (GD3).

A method is described for the preparation of ganglioside Glac2 [(II3(NeuAc)2-LacCer, GD3] from cream of bovine milk using liquid-phase extraction with methanol or ethanol followed by anion exchange chromatography. The method is rapid and inexpensive; 1 kg cream, centrifuged from 14-15 L of bovine milk, yields approximately 70 mg of pure ganglioside Glac2. The sialic acid constituent of ganglioside Glac2 isolated from bovine milk cream consists solely of the N-acetylneuraminic acid derivative. The major components of its ceramide consist of octadecasphing-4-enine and the 22:0 (behenic acid) and 23:0 fatty acids.

Animals↗

Characterization of anti-ganglioside antibodies present in normal human plasma.

Samples of plasma from normal human adults were screened for anti-ganglioside antibodies by HPTLC-immunostaining and enzyme-linked immunosorbent assay (ELISA). All the samples analyzed showed IgM-immunoreactivity to GM1 ganglioside and its related glycolipid GA1. Reactivity to GD1b, GM2 and LM1 was also detected in 85, 80 and 20% of the analyzed samples, respectively. The main immunoreactivity is related to the asialo-ganglioside GA1. Using inhibition by soluble antigen and affinity chromatography techniques it was possible to distinguish two populations of anti-GA1 antibodies. One with high affinity reacting only with GA1, and another with low affinity reacting also with GM1 and GD1b. The antibodies that recognize GM2 are of low affinity and appear to be different from those that react with GA1. We postulate that the anti-GM1/GD1b immunoreactivity present in normal human plasma could be a cross-reaction of antibodies originally directed to a GA1-like carbohydrate structure. Anti-GA1 and anti-GM1 titers were calculated as the reciprocal of the plasma dilution needed to obtain the half maximal antibody binding, a titer definition that we consider more suitable to compare data from different laboratories than those usually employed.

Antibodies↗

Specific immunization using keyhole limpet hemocyanin-ganglioside conjugates.

In a search for adjuvants of non-bacterial origin for immunization with ganglioside, we investigated whether chemical coupling to immune stimulatory protein could increase the immunogenicity of sialoglycosphingolipid. A novel method for the linkage of glycosphingolipids, including gangliosides, to protein was established. The procedure includes lysis of the sphingoid double bond by ozone, reduction of the ozonolysis product to the aldehyde, and coupling to amino groups, either directly by reductamination, or by conjugation via a long aliphatic chain dicarboxylic acid linker. Using this method, gangliosides Gfpt1 (IV2-Fuc-, II3NeuAc-Gg4Cer), Glac2 [II3(NeuAc)2-LacCer], and Gtet1 (II3NeuAc-Gg4Cer) were coupled to keyhole limpet hemocyanin (KLH), and the immunogenicity of the conjugates was tested. Immunization of mice with the KLH-ganglioside conjugates led in each case to the formation of IgG- and IgM antibodies that recognized the underivatized gangliosides, respectively. In contrast to this, mixtures of KLH and ganglioside proved ineffective for immunization. KLH-tumor-associated ganglioside conjugates may, therefore, be considered as possible vaccines in immune therapy of cancer.

Adjuvants, Immunologic↗

Serum immunoglobulins in Heymann's experimental nephritis modulate binding of properdin and factor-H to sulpho-glycosphingolipids II3SO3(-)-Gg3Cer and III3SO3(-)-,II3SO3(-)-Gg3Cer.

The nephropathic effects of Heymann's experimental nephrites involve autoallergic serum antibodies directed against rat kidney membrane constituents. In assessing the action of glycolipids as possible autoallergens in these conditions, it was found that heterologous and autologous Heymann's nephritis sera antibodies recognize that rat kidney sulphatides, II3SO3(-)-Gg3Cer (Stri1), and III3SO3(-)-,II3SO3(-)-Gg3Cer (Stri2). Two antibody populations in Heymann's sera, each reacting with only one of the two sulphatides, could be observed. It was further shown that human factor-H and properdin, pivotal regulators of the alternative pathway of complement activation, both bound to Stri2 in vitro. This binding of factor-H and properdin was differentially affected by affinity-purified anti-Stri2 antibodies of Heymann's nephritis sera. Whereas the interaction between factor-H and Stri2 was inhibited by the antibody, that of properdin was enhanced.

Animals↗

Induction of phosphatidic acid by fibroblast growth factor in cultured baby hamster kidney fibroblasts.

Basic fibroblast growth factor (bFGF/FGF-2) is a strong mitogenic inducer of cultured baby hamster kidney (BHK) cells. When cultured BHK cells were stimulated with FGF-2, phosphatidic acid (PA) was induced within 2 min, peaked at 5 min and gradually decreased. Phospholipase D (PLD) was also mitogenic for cultured BHK cells and this effect was mediated via PA. The possibility that PA induction by FGF-2 is an essential signaling step for BHK cell proliferation is discussed.

Animals↗

Immunochemical analysis of insect carbohydrate antigenic determinants: recognition of a terminal alpha-linked N-acetylgalactosamine-containing epitope of Calliphora vicina neutral glyco(sphingo)lipids and detection in additional orthopteran and dipteran species.

A cloned mouse hybridoma was established that secreted a monoclonal antibody directed against certain neutral glycosphingolipids of the third-instar larvae of Calliphora vicina (Insecta: Diptera). The isotype of the designated monoclonal antibody CNF-I (Calliphora Neutral Fraction) was determined as IgG3. By the use of purified neutral glycosphingolipids of C. vicina, qualitative thin-layer chromatography immunostaining and semi-quantitative enzyme-linked immunosorbent assay determinations, the epitope was specified as a terminal alpha 1-4-linked N-acetylgalactosamine to subterminal N-acetylgalactosamine, which is present on the components GalNAc alpha 4GalNAc beta 4GlcNAc beta 3Man beta 4Glc beta lCer (N5a) and GalNAc alpha 4GalNAc beta 4-(6' PEtn-)GlcNAc beta 3Man beta 4Glc beta lCer (Nz5a). After enzymatic removal of the terminal alpha-N-acetylgalactosamine residue, the epitope reactivity was destroyed. The distribution of the CNF-I recognized epitope among neutral glycolipids of other insects was shown for: Locusta migratoria (Insecta: Orthoptera); and, Chironomus tentans and Drosophila melanogaster (Insecta: Diptera).

Acetylgalactosamine↗