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PubMed1985

Proton NMR and fast-atom bombardment mass spectrometry analysis of the melanoma-associated ganglioside 9-O-acetyl-GD3.

A glycolipid antigen, detected by a monoclonal antibody (ME 311) obtained by immunizing mice with a human metastatic melanoma cell line (WM 46), was isolated and structurally characterized. Using immunostaining on thin-layer chromatograms for monitoring, 1.0 mg of a pure alkali-labile disialoganglioside was obtained from 23 g of packed melanoma cells (WM 164). Fractionation of the lipid extract was done on DEAE-Sepharose columns into total disialogangliosides which were repeatedly separated by high-pressure liquid chromatography. On mild alkaline treatment, the ganglioside was converted to a slower migrating species identical with a ganglioside GD3 isolated from the same source (Neu5Ac alpha 2----8Neu5Ac alpha 2----3Gal beta 1----4Glc beta 1----1-cer-amide) and specifically detected by monoclonal antibody R24. Comparison of the two gangliosides by fast-atom bombardment mass spectrometry (revealing an acetyl group on the terminal sialic acid on the alkali-labile species) and by 1H NMR (indicating the position of the acetyl group) suggested the following structure: Neu5,9Ac2 alpha 2----8Neu5Ac alpha 2----3Gal beta 1----4Glc beta 1----1-ceramide. This is identical with a ganglioside proposed earlier to exist in melanoma cells (Cheresh, D. A., Varki, A. P., Varki, N. M., Stallcup, W. B., Levine, J., and Reisfeld, R. A. (1984) J. Biol. Chem. 259, 7453-7459). Immunostaining with ME 311 antibody of cell extracts on thin-layer chromatography chromatograms revealed only this ganglioside in the melanoma cells, while normal human brain was negative. However, in one of the total ganglioside extracts tested for presence of binding with antibody ME 311, three gangliosides were found to bind. No evidence was obtained for the presence of the antigenic epitope in mucins or glycoproteins of the melanoma cells.

Antibodies, Monoclonal↗
PubMed1977

Structure of tetanus toxin. II. Toxin binding to ganglioside.

The interaction between tetanus toxin and ganglioside containing 2 N-acetylneuraminic acid residues linked in sequence to one another has been investigated using a new method involving radioactively labeled ganglioside and tetanus toxin adsorbed to Sephadex matrix. Binding between the two components was demonstrated, and it was calculated that in the nanomolar concentration range, tetanus toxin becomes half-saturated at about 5 X 10(-8) M concentration of ganglioside. Removal of the ceramide portion from the ganglioside resulted in the complete loss of binding activity, whereas removal of the terminal N-acetylneuraminic acid residue from the intact ganglioside had no effect. Among the fragments derived from tetanus toxin (Helting, T. B., and Zwisler, O. (1977) J. Biol. Chem. 252, 187-193), only the heavy chain polypeptide exhibited a binding activity of the same order of magnitude as that observed for the native toxin. The light chain polypeptide showed no interaction with ganglioside and among the fragments derived from the toxin by digestion with papain, only Fragment C, at a high protein concentration, displayed marginal binding activity. Using monovalent antibodies directed against specific regions of the tetanus toxin molecule, it was demonstrated that antibodies directed against Fragment C uniquely interfere with the binding process. Anti-light chain serum was ineffective, as well as antitetanus toxoid serum previously absorbed with Fragment C. It is concluded that the binding site for ganglioside is located on the heavy chain portion of tetanus toxin, possibly in or near the region comprised by Fragment C.

Binding Sites↗
PubMed1980

Regulation of lymphocyte responses by human gangliosides. I. Characteristics of inhibitory effects and the induction of impaired activation.

Gangliosides obtained from normal human brain were found to inhibit the in vitro activation of human lymphocytes by nonspecific mitogens and allogeneic cells at concentrations between 3 to 50 microgram/1.5 to 1.7 X 10(5) lymphocytes/0.2 ml culture. Ganglioside inhibition did not represent cytotoxic effects or altered lectin binding and was independent of the mitogen concentration. In addition to concentration, the degree of inhibition was dependent on the mode of presentation to lymphocytes, since gangliosides incorporated within liposomal membranes displayed a synergistic inhibitory effect greater than predicted from the cultures receiving either gangliosides or liposomes alone. In binding experiments, radiolabeled ganglioside GM1 became associated with human lymphocytes within 10 min. However, approximately 72 hr pre-exposure of human lymphocytes to gangliosides was required to induce impaired lymphocyte responses to mitogens and allogeneic cells. Thus, concentrations of human gangliosides equivalent to the levels occurring in the sera of patients with certain malignancies are capable of actively inhibiting lymphocyte stimulation in addition to inducing impaired lymphocyte responses.

Binding Sites↗
PubMed1983

Shedding and immunoregulatory activity of YAC-1 lymphoma cell gangliosides.

YAC-1 lymphoma cells, both when cultured in vitro and when passaged in ascites form in vivo, synthesize gangliosides (means of 22.1 and 14.7 nmol lipid-bound sialic acid isolated per 10(8) cells, respectively) with potent inhibitory effects on mitogen- and antigen-induced lymphoproliferation: 10 to 30 nmol highly purified YAC-1 gangliosides/ml caused greater than 90% inhibition of proliferative responses of murine lymphocytes to concanavalin A, lysozyme (a soluble specific antigen), and allogeneic cells (mixed-lymphocyte response). Measureable quantities of these gangliosides were shed by the tumor cells in vitro and also were recovered from the ascites fluid in vivo. Furthermore, the gangliosides isolated from ascites fluid (mean of 15.3 nmol/ml) had inhibitory activity of a magnitude similar to that of the gangliosides isolated from the tumor cells. Therefore, significant inhibition of normal lymphoproliferative responses by tumor-derived gangliosides occurred at ganglioside concentrations which are actually present in the fluid surrounding the tumor cells in vivo. These results support the hypothesis that shedding of gangliosides may serve to protect tumor cells from host immune destruction.

Cells, Cultured↗
PubMed1983

Effects of human brain cell culture conditions on [14C]glucosamine radioactivity incorporation into gangliosides.

Human glioma cells (12-18) and fetal neural cells (CH II) in culture were exposed for 20 hr to [14C]glucosamine to determine the level and distribution of radiolabel incorporated into gangliosides. Cells of identical passage levels at two stages of growth, preconfluent and confluent, were preincubated for 0 to 60 hr in serum-free medium (SFM). Both higher cell densities and longer incubations in SFM caused a change in the amounts and patterns of radiolabeled gangliosides. Preincubation for 60 hr in SFM caused an increase (P less than 0.05) in the percent of total recovered ganglioside radiolabel in GM1 of CH II cells, from 10.5 to 16.7% in preconfluent cells and from 14.1 to 31.9% in confluent cells. Conversely, the proportion of radiolabel in GM3 and GM2 decreased with longer preincubations in SFM. A similar preincubation of glioma cells caused an increase in the proportion of label into GD1a of both preconfluent and confluent cells (P less than 0.02) from 4 to 11% of the total ganglioside radioactivity. Higher cell densities also resulted in consistently higher percent (of total ganglioside) incorporation into GD1a of 12-18 cells (P less than 0.05) and GM1 of CH II (P less than 0.01). These results show that there is a shift in the incorporation of precursor label into more complex gangliosides under conditions associated with the arrest of cell division. These phenomena may represent a regulatory response of the ganglioside biosynthetic apparatus to changes in extracellular environment and cell contact.

Brain↗
PubMed1982

Neutral glycosphingolipids and gangliosides of bovine thyroid.

By the application of a ganglioside-mapping technique, the lipid composition of bovine thyroid was analyzed systematically. The contents of cholesterol, lipid-bound phosphorus and lipid-bound sialic acid in bovine thyroid were 5.10, 9.76, and 0.28 mumol/g of dry tissue, respectively, and the molar ratio of cholesterol, lipid-bound sialic acid, and lipid-bound phosphorus was 52.4 : 2.9 : 100.0. The following phospholipids were contained in this order: phosphatidylcholine greater than phosphatidylethanolamine greater than sphingomyelin greater than phosphatidylserine and phosphatidylinositol greater than cardiolipin. When compared on a molar basis, the amount of total glycosphingolipids was only 3% of phospholipids. As the major neutral glycosphingolipids, ceramide glucoside, ceramide galactoside, ceramide lactoside, ceramide trihexoside and globoside were identified and the most abundant component was globoside (40% of total neutral glycosphingolipids). On the other hand, five molecular species of gangliosides were identified: GM3, GM1, fucosyl GM1, GD3, and GD1a. Three types of GD3 and GD1a with a different sialic acid composition were recognized on the ganglioside-map and isolated in pure forms. GM3 was the most abundant component, but the concentration of gangliosides with ganglio-N-tetraose in bovine thyroid was higher than that of gangliosides with lactose. Also fucosyl GM1 comprised 13% of total gangliosides. Thus, the high concentrations of gangliosides with ganglio-N-tetraose and fucosyl GM1 seemed to be characteristic of bovine thyroid glycosphingolipids. The glycosphingolipids contained in the following order: GM3 greater than GD1a greater than globoside greater than GM1 greater than ceramide trihexoside greater than fucosyl GM1 greater than ceramide lactoside greater than ceramide glycoside greater than GD3 greater than ceramide galactoside.

Animals↗
PubMed1981

[Gangliosides of mouse liver and ascites hepatoma 22a].

The ganglioside composition of the ascite hepatoma 22a and that of mouse liver was compared. GM2 was shown to be the main ganglioside in both tissues; however, the gangliosides of the hepatoma differed from liver gangliosides by a higher amount of disialoganglioside GD1a and by contents of monosialoganglioside GM1 and disialoganglioside GD1b which are absent in normal mouse liver. Trisialogangliosides which are characteristic for normal liver cells were not detected in the hepatoma. The liver and hepatoma gangliosides differed also by the type of sialic acids. In the liver the individual ganglioside fractions belong to either the N-glycolyl- or the N-acetylneuraminyl series, whereas the ganglioside fractions of the hepatoma are characterized by simultaneous presence of both sialic acid types.

Animals↗
PubMed1995

Gangliosides of anencephalic and fetal brain--immunostaining on thin-layer chromatograms.

The expression of gangliosides of ganglio-series as well as neolacto-series gangliosides in anencephalic and in normal human fetal brain was compared with that in adult brain by immunostaining on thin-layer chromatograms. A difference in the expression of ganglio-series gangliosides with GM1a core was found between anencephalic and normal fetal brain, with less expression of GM1a and GD1a in anencephaly compared with normal fetal brain, in which these gangliosides dominate. Small amounts of GM1b were detected in fetal brain whereas only traces were found in anencephalic brain. Lactosamine-containing gangliosides were present in fetal and in anencephalic brain as alpha 2-3 as well as alpha 2-6 sialylated nLcOse4Cer structures. A heterogeneous group of neolacto-series gangliosides was expressed in anencephalic brain in both the monosialo- and presumed disialoganglioside range. These findings demonstrate a significant change in ganglioside pattern in anencephaly where the process of cell differentiation and maturation has been severely disturbed.

Anencephaly↗
PubMed1995

[Autoantibodies to ganglioside GM3 and serotonin in blood serum in atherosclerosis].

Using ELISA method, the sera from 17 patients with atherosclerosis and 13 normal controls were examined for ganglioside- and serotonin-reactive antibodies. Gangliosides from human liver (GM31) and human aorta (GM3a) as well as GM2, GM1, GT1b, human brain cerebrosides and the BSA-serotonin conjugate (5-HT) were used as antigens. A group of patients showed statistically significant higher levels of anti-GM31 (82%) and anti-5-HT (71%) as compared to the control group. Taking into account the identical fatty acid composition of GM3 from human liver and platelets, one can assume that antibodies are produced against blood clot gangliosides in atherosclerotic patients' sera. This conclusion is supported by a high correlation (r = 0.06, p < 0.01) between the level of antibodies to 5-HT and GM31 in the sera of all patients. The sera of three patients with the highest content of antibodies to GM31 were shown to contain antibodies to GM3a and GT1b which were absent in control sera. No reaction with brain cerebrosides or GM1 and GM2 was detected in the sera of the examined persons. The differences in sera reactions with GM31 and GM3a can be explained as resulting from differences in the chain length of fatty acid residues of the ceramide moiety of gangliosides. The data obtained confirm the fact that antibodies to aorta gangliosides appear in the sera of atherosclerotic patients. Thus, the formation of atherosclerotic plaques leading to platelet activation, clot formation and ganglioside accumulation in aortic cells increase the levels of anti-ganglioside GM3 antibodies.

Aorta↗
PubMed1993

Antibodies to gangliosides in Guillain-Barré syndrome: specificity and relationship to clinical features.

Antibodies to ganglioside GM1 have been associated with Guillain-Barré syndrome. To clarify their role we have studied their frequency, fine specificity and relationship to clinical features in a series of patients with this disease. Antibodies to ganglioside GM1 were identified, by both enzyme-linked immunosorbent assay and binding to thin-layer chromatograms of human brain, in 12 (28.6%) of 42 patients with Guillain-Barré syndrome and in only 1 (2.4%) of 41 normal control subjects (p = 0.002). Eight sera contained IgM antibodies and six sera contained IgG antibodies, including 2 sera which contained both. The fine specificity of the sera varied. Only four of the 12 sera also showed reactivity with ganglioside GD1b and gangliotetraosyl-ceramide (asialo-GM1), consistent with reactivity with the terminal Gal beta 1-3GalNAc disaccharide. Two sera had low titre anti-asialo-GM1 antibodies of a different class to the anti-ganglioside GM1 antibodies. The antibodies in these sera therefore react with a variety of epitopes. There was a strong relationship between the presence of anti-ganglioside GM1 antibodies in the acute stage and prolonged disability, especially if IgG antibodies were present. Seven of 12 patients with anti-ganglioside GM1 antibodies had serological evidence of recent Campylobacter jejuni infection, but antigens from a strain of this bacterium not associated with Guillain-Barré syndrome did not absorb the anti-ganglioside GM1 antibodies.

Adult↗
PubMed1995

Neutralization of the effect of Crotalus durissus terrificus venom by gangliosides.

We determined the ability of a mixture of gangliosides (16% GD1b, 19% GT1b, 21% GM1, 40% GD1a) to neutralize the effect of Crotalus durissus terrificus (Cdt) venom in vitro and in vivo. Protection was indicated by the absence of muscular contractions, hind limb paralysis or death of BALB/c mice (16-18 g) after receiving Cdt venom (1 microgram Cdt venom containing 0.6 microgram protein) at the doses indicated. A dose of Cdt venom above 0.9 microgram (ip) or 1 microgram (im) induced muscular contraction and above 1.2 micrograms (ip) or 5.5 micrograms (im) the venom induced muscular contraction and hind limb paralysis. Cdt venom above 2.5 micrograms (ip) or 9 micrograms (im) induced all these symptoms and 95 to 100% death in experimental animals. The lethal dose 50% of the Cdt venom used was 8 micrograms (im) and 1.5 micrograms (ip). In in vitro studies, 4 mg gangliosides neutralized the effect of up to 1.5 micrograms Cdt venom. Quantities as low as 0.2 mg gangliosides were capable of neutralizing 0.9 microgram of Cdt venom in vitro. Intramuscular treatment with 1 mg gangliosides performed 60 min after the intramuscular injection of 5 micrograms Cdt venom protected 100% of the animals. In contrast, no protection was achieved with intraperitoneal treatment with gangliosides. The data show that gangliosides were effective in neutralizing the toxic effects induced by Crotalus durissus terrificus venom both in vitro and in vivo and that post-exposure intramuscular treatment with gangliosides could protect animals experimentally inoculated with the venom.

Animals↗
PubMed1995

[The metabolism of radiolabelled GM1-ganglioside in cultured skin fibroblasts from controls and patients with GM1-gangliosidosis].

The metabolism of [3-3H-sphingosine] GM1-ganglioside was studied in cultured skin fibroblasts from control and patients with beta-galactosidase deficiency, primarily or secondarily. When dissolved in the medium with phosphatidylserine, GM1-ganglioside was efficiently taken up by cultured skin fibroblasts and transferred into lysosomes. A pulse-chase study revealed that [3-3H-sphingosine] GM1-ganglioside was metabolized to GM2-, GM3-ganglioside, ceramide, ceramide monohexoside, ceramide dihexoside and sphingomyelin. In a 20h pulse study, cell lines from patients with GM1-gangliosidosis of infantile, juvenile and adult types hydrolyzed 2 approximately 5%, 20 approximately 44% and 54 approximately 58% of the total endocytosed GM1-ganglioside respectively. These values were lower than in the control cells (62.2 +/- 5.43% (n=10). The hydrolysis rates of exogenous [3-3H-sphingosine] GM1-ganglioside in cultured skin fibroblasts from various types of GM1-gangliosidosis closely correlated to the clinical severity. This method is also useful to the diagnosis of impaired ganglioside metabolism.

Cells, Cultured↗
PubMed1996

Simplified ganglioside composition of photoreceptors compared to other retinal neurons.

PURPOSE: The quantitative and qualitative ganglioside composition of retinal photoreceptor cells is unknown. The aim of this study was to analyze the lipid, especially ganglioside, make-up of photoreceptors compared to other retinal cells. METHODS: Retinas from adult normal rats were mechanically separated into outer (photoreceptors) and inner (other retinal neurons and glia) halves be planar vibratome sectioning. Total lipids were extracted, and each fraction (neural, phospholipids, and glycosphingolipids) was eluted sequentially by column chromatography and quantitated through high-performance thin layer chromatogram analysis. Similar analyses were performed on entire retinas from adult normal rats, adult dystrophic rats lacking photoreceptors (RCS-rdy-p+ strain), and isolated photoreceptor outer segments. RESULTS: Whereas phospholipids were distributed equally between the two halves, inner retina contained significantly more cholesterol (68% total) and gangliosides (74% total) than outer retina on a unit protein basis. The distribution on a percent molar basis of specific gangliosides also was significantly different between the two halves: Outer retina was dominated by GD3 (45% total ganglioside) and contained only trace amounts (<4%) of complex species (GT1b and GQ1b); inner retina was more typical of mature brain tissue exhibiting substantial amounts (approximately 25%) of more complex species. These data were supported by lipid compositional analyses of mutant photoreceptor-less retina. However, isolated outer segments resembled whole retina in containing higher levels of complex gangliosides. CONCLUSIONS: These data indicate that, compared to other central nervous system-derived neurons, photoreceptor cell body membranes exhibit a highly unusual simplified ganglioside composition. Such an unusual neuronal lipid composition may reflect structural adaptations to their specialized function.

Animals↗
PubMed1996

Gangliosides reduce the development of ethanol dependence without affecting ethanol tolerance.

Mice given an ethanol-containing liquid diet, as their sole source of nutrients and fluid, rapidly developed functional tolerance to and physical dependence on ethanol. The presence of physical dependence was demonstrated by measured signs of central nervous system hyperexcitability upon withdrawal of ethanol. The withdrawal hyperexcitability, which included tremors, handling-induced seizures and spontaneous clonic/tonic seizures, was more pronounced when mice consumed the ethanol-containing diet for 7 days, compared with 5 days. Daily treatment of the animals with either a ganglioside mixture (extracted bovine brain gangliosides, 250 or 500 mg/kg i.p.) or ganglioside GM1 (100 mg/kg i.p.) for the terminal two-thirds of the ethanol administration period resulted in a significant reduction in the ethanol withdrawal signs. On the other hand, tolerance to the hypnotic action of ethanol, tested 30 hr after withdrawal of ethanol, was unaffected by ganglioside treatment. Ganglioside GM1 given i.c.v. at a daily dose of 10 micrograms during the ethanol ingestion period was as effective as 100 mg/kg GM1 given i.p. in reducing signs of ethanol withdrawal. The daily administration of gangliosides during the feeding of the ethanol diet did not alter the animals' ethanol consumption, intoxication or blood ethanol levels at the time of ethanol withdrawal. A single dose of GM1 given either i.p. or i.c.v. 16 hr before withdrawal produced no effect on the measured ethanol withdrawal signs. Our prior work and the work of others has demonstrated a relationship between up-regulation of N-methyl-D-aspartate receptor numbers in brain and the manifestation of ethanol withdrawal signs. Daily administration of GM1, during the last 5 days of a 7-day period of ethanol ingestion, prevented the up-regulation of N-methyl-D-aspartate receptors in the hippocampus and reduced the ethanol withdrawal signs. Our data demonstrate that the daily administration of gangliosides during the period of ethanol consumption may prevent the development of ethanol physical dependence, while leaving ethanol tolerance intact.

Animals↗
PubMed1996

Quantification of gangliosides by microbore high performance liquid chromatography.

A highly sensitive analytical method was developed that allows the separation of ganglioside mixtures and quantification of individual non-derivatized gangliosides in the concentration range between 2 pmol and 1 nmol. Gangliosides were separated with a gradient of acetonitrile/phosphate buffer on a 1 mm diameter microbore HPLC column packed with Spherisorb-NH2. They eluted according to their number of sialic acid residues with increasing phosphate and decreasing acetonitrile concentrations. The separation of different gangliosides with equal sialic acid content is also described. The column effluent was monitored at the maximum of absorption at 197 nm. The sensitivity is higher than resorcinol staining of fractionated gangliosides by thin layer chromatography, previously the standard method for ganglioside analysis. The separated gangliosides can be analyzed by further methods. The HPLC method described here has been applied to the analysis of serum and oligodendroglioma specimens.

Chromatography, High Pressure Liquid↗
PubMed1996

Gangliosides expressed in human breast cancer.

Breast tumors that were histopathologically diagnosed as invasive ductal carcinoma were examined in relation to their abnormal expression of gangliosides. Total ganglioside levels that were expressed as lipid-bound sialic acids were significantly higher in breast tumor tissues than in normal mammary tissues. Two kinds of unusual gangliosides were found to be expressed in many cases of breast tumors. One was a group of O-acetylated gangliosides, such as O-acetyl-GD3 and O-acetyl-GT3. They are known as fetal gangliosides, which appear in fetal brains. The other was an N-glycolylneuraminic acid-containing ganglioside, N-glycolyl-GM3, which had not been previously found in normal human tissues. The finding that unusual gangliosides are expressed in breast tumors may provide the basis for their immunological diagnosis and vaccine therapy.

Breast Neoplasms↗
PubMed1997

Ganglioside biosynthetic gene expression in experimental mouse brain tumors.

The genes for cytidine monophospho-N-acetylneuraminic acid hydroxylase (NeuAc-H) and beta-1,4-N-acetylgalactosaminyl transferase (GalNAc-T) were examined using reverse transcription-PCR in two experimental mouse brain tumors, EPEN and CT-2A. NeuAc-H is required for the synthesis of gangliosides containing N-glycolylneuraminic acid, whereas GalNAc-T is required for the synthesis of ganglioside GM2. The genes were analyzed in solid tumors grown in vivo and in tumor cells grown in vitro. NeuGc-containing gangliosides are abundant in cells of the mouse immune system, including macrophages, but are undetectable in normal mouse brain. GM2 is expressed in both neural and nonneural mouse cells and tissues. The EPEN tumor cells synthesize only ganglioside GM3, whereas the CT-2A tumor cells synthesize GM3, GM2, GM1, and GD1a. NeuAc-H gene expression was detected in both solid tumors grown in vivo but was undetectable in either tumor cell line. The presence or absence of NeuAc-H gene expression in the tumor tissues and cells correlates with the presence or absence, respectively, of NeuGc-containing gangliosides. Differences in GalNAc-T gene expression between the solid tumors and the cultured tumor cells correlate with the expression of ganglioside GM2. The findings suggest that the differences in ganglioside biosynthetic gene expression between brain tumors grown in vivo and in vitro are associated with the presence or absence, respectively, of tumor-infiltrating host cells.

Animals↗
PubMedDate not supplied

[Composition of the carbohydrate component and fatty acids of the chief gangliosides of the brains of cartilaginous fish].

Ganglioside composition has been studied in the brain of 5 Elasmobranch fishes (3 sharks: Carcharhinus longimanus, Carcharhinus sp., Squalus acanthias and 2 rays: Dasyatis pastinaca, Raja clavata). For the identification of ganglioside fractions, molar ratio of glucose, galactose, NANA and sphingosine as well as the presence of hexosamine were determined in the main gangliosides from the brain of the shark C. longimanus. The data obtained indicate that the majority of brain gangliosides in Elasmobranchs contain a reduced carbohydrate chain as compared to the main gangliosides from mammalian brain. Thus in C. longimanus and Carcharhinus sp. GD3, disialoganglioside containing only two hexose residues in its molecule, constitutes approximately 30 per cent of ganglioside sialic acid. Considerable amounts of GD2, GM3 and GM2 were found in Elasmobranch brain as well. Investigation of fatty acid composition of gangliosides from the brain of C. longimanus revealed the predominance of stearic acid (C18:0) in all the fractions studied.

Animals↗