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The isolation and purification of a neutral glycolipid fraction fromTaenia crassiceps metacestodes (KBS strain), harvested from both male and female NMRI mice at 70–80 days following intraperitoneal infection, revealed 24 thin-layer chromatography-designated glycolipid bands. The glycolipids were defined as ceramide mono-(n=3), di-(n=3), tri-(n=4), tetra-(n=5), and >tetrasaccharides (n=9) according to their running properties as defined by thin-layer chromatography against standards of known structure. The defined glycolipids were tested for immunoreactivity with sera from noninfected andT. crassiceps-infected NMRI mice (intraperitoneal injection or implantation of 15 larvae/animal) using the enzyme-linked immunosorbent assay (ELISA) until day 33 p.i. (IgM and IgG reaction) and high-performance thin-layer chromatography (HPTLC) combined with immunostaining (IgG reaction) until day 7 p.i. ELISA-determined IgM and IgG titres were significantly elevated from day 5 p.i. Immunostaining revealed early reactivity for certain ceramide tetra- and >tetrasaccharides (n=6) on day 3 p.i. From day 5 p.i. onwards, nearly all glycolipids, including ceramide mono-and disaccharides, were recognized by the sera from metacestode-challenged mice. On day 7 p.i., a total of 22 bands were serologically active; of these, a considerable number (n=10) showed increased staining intensity. Remarkably, in many cases (10 of 20), 3 glycolipids (tetra-and >tetrasaccharides) were weakly recognized by mouse sera taken before infection.

Summary Human meninges and 29 meningiomas were analyzed as to their glycosphingolipid composition. In the neutral fraction GSL, a mostly even distribution of mono-, di-, tri-and tetrahexoside was demonstrated. In the group of the gangliosides, Glac 1 in one broad band in chromatogramms occurred in almost all meningiomas; Glac 2 was present in 84% of tumours. Members of the Gtri-family were only found in a small minority of tumours while various Gtet-gangliosides were detectable in nearly half of them. No constant pattern or patterns emerged and no correlation to either morphological subtype or malignancy grade could be established. Immunohistochemistry revealed focal presence of Glac 2 in a pattern similar to that of vimentin expression. Semiquantitative evaluation showed good correlation between both parameters.

Host cell as well as viral DNA synthesis in human fibroblasts infected with human cytomegalovirus was found to be largely resistant even to high concentrations sodium butyrate. Likewise, production of viral progeny was reduced by 1–2 orders of magnitude but not abolished. On the other hand, the drug allowed (modified) glycosylation only of viral polypeptides whereas t h a t of host proteins was suppressed. Immunofluorescence studies on living cells suggested that butyrate may interfere with processing and intracellular transport of virus-specific surface membrane antigens.

Abstract:  Sulfatides1 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 Sga1l, 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(–)-3Galβ< 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.

Four neutal fraction glycosphingolipids, designated components 4-7, were purified from the pupae of Calliphora vicina and isolated by the use of high performance liquid chromatography. Their chemical structures were determined to be: GalNAc(beta 1-4)GlcNAc(beta 1-3)Man(beta 1-4)Glc(beta 1-1)Cer; GalNAc(alpha 1-4)GalNAc(beta 1-4)GlcNAc(beta 1-3)Man(beta 1-4)Glc(beta 1-1)Cer and Gal(alpha 1-3)GalNAc(beta 1-4)GlcNAc(beta 1-3)Man(beta 1-4)Glc(beta 1-1)Cer; Gal(beta 1-3)GalNAc(alpha 1-4)GalNAc(beta 1-4)GlcNAc(beta 1-3)Man(beta 1-4)Glc(beta 1-1)Cer; and GlcNAC(beta 1-3)Gal(beta 1-3)GalNAc(alpha 1-4)GalNAc(beta 1-4)GlcNAc(beta 1-3)Man(beta 1-4)Glc(beta 1-1)Cer. By the use of specific exoglycosidases, it was possible to assign anomeric configurations to all the sugar residues present. Analysis of the ceramide moiety by electron-impact mass spectrometry revealed the dominant fatty acid and sphingoid to be arachidic acid (C20:0) and tetradecasphing-4-enine, respectively.

Host cell as well as viral DNA synthesis in human fibroblasts infected with human cytomegalovirus was found to be largely resistant even to high concentrations sodium butyrate. Likewise, production of viral progeny was reduced by 1–2 orders of magnitude but not abolished. On the other hand, the drug allowed (modified) glycosylation only of viral polypeptides whereas that of host proteins was suppressed. Immunofluorescence studies on living cells suggested that butyrate may interfere with processing and intracellular transport of virus-specific surface membrane antigens.

The tasks of process computers comprice daily planning, material flow, laboratory analyses, trouble acquisition, the metailirgical and energetical electric furname handling and daily reporting. The information requirements of process personnel and management especially requires acquisition of datas via inputs directly in the control stands, besides automatic data gathering Data acquisition, gives special demands to the availability of hardware, including measurement points. prerequisits for use of terminals in the control stands are their easy handling and short response times. The communication system was realized with several couopied process and microcomputers.

Summary 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.

The effect of monensin on glycosphingolipid metabolism was reinvestigated. It was found that monensin increased the uptake of [3H]galactose by human fibroblasts, causing an enhanced metabolic labelling of glycosphingolipids. The preferential incorporation of radioactivity into ceramide monosaccharide in the presence of monensin was accompanied by an equally increased rate of degradation. However, using radiolabelled precursors of the ceramide moiety, a generally diminished uptake of radioactivity into all glycosphingolipids was observed under the influence of monensin, with the exception of mono- and di-hexosylceramide. The enhanced incorporation of radiolabel by these two glycolipids, as well as their increased cellular chemical content, may reflect early synthesis in a monensin-insensitive pre-Golgi compartment after disruption of the cellular Golgi transport system by monensin.

Monoclonal antibodies (mAbs) BW 625 and BW 704, of the IgG3 isotype, bound to immunochemically indistinguishable epitopes on ganglioside II3(NeuAc)2-GgOse3-Cer. Despite this fact the mAbs showed a differential binding pattern on human glioma cell lines i.e. immunohistochemical data indicate that the detected epitopes are not identical. Furthermore, either mAb is able to mediate the antibody-dependent cellular cytotoxicity reaction (ADCC) and the human-complement-dependent cytotoxicity reaction (CDC) with epitope-expressing tumor cells. All cryopreserved tissue specimens from gliomas and neuroblastomas were immunohistochemically stained, whereas the other small round cell tumors of childhood, as well as melanomas and small-cell lung carcinomas, were essentially negative. Positive staining of normal cryopreserved tissues was restricted to amyelinic axons, Hassal's bodies and some connective tissue fibers in thymus and the tegumentary epithelium of skin. The high selectivity of mAb BW 704 for gliomas and neuroblastomas, the lack of cross-reactivity with major tissues and the strong ADCC and CDC potential argue for the use of mAb BW 704 in immunotherapy of neuroblastomas and gliomas.

Lp(a)-lipoprotein of human serum, when isolated by ultracentrifugation and gelfiltration on Sepharose 4 B, may disaggregate into several components either spontaneously or by mild treatment with detergents:

Through application of refined separation techniques the ß-Lp(a+)-lipoprotein of human serum was characterized in an immunologically and electrophoretically pure form. It was analyzed with regard to its lipid-composition and compared to likewise electrophoretically and immunologically pure ß-Lp(a-)- and a1-lipoproteins.

Gelelectrophoretic studies of the serum lipoprotein fraction HDL2 (1.0632-fraction a lipoprotein with the electrophoretic mobility characteristic of the Lp(a)-lipoprotein. This observation confirmes previous suggestions, that Lp(a) indeed is a quantitative genetic trait.

Aus Glykosphingolipiden ist durch Einwirkung von Ozon und anschließender Behandlung mit Alkali der unversehrte Kohlenhydratanteil erhältlich. Die Struktur des so aus Gangliosid GGNTIV gewonnenen sauren Oligosaccharides, in dem die Ganglio-N-tetraose noch alle drei Sialinsäurereste trägt, wird weiter erhärtet.

Im Gangliosid GIIträgt jede der beiden Galaktosen in 3-Stellung eine Sialinsäure. Im isomeren Gangliosid GIII, das Tetanustoxin viel stärker bindet, sind die beiden Sialinsäuren direkt miteinander verknüpft. Das Gangliosid GIVvereinigt in sich die Bauprinzipien von GIIund GIII