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PubMed1982

Fabry disease: detection of heterozygotes by examination of glycolipids in urinary sediment.

Fabry disease is an X-linked sphingolipid disorder that is manifest clinically as a disease of nerves, kidneys, and blood vessels. Precise identification of Fabry heterozygotes is essential for genetic counseling. Heterozygote detection by enzyme assay does not consistently distinguish them from unaffected females. We describe a method for Fabry heterozygote detection, based on quantitation of urinary sediment glycolipids by high-performance liquid chromatography. In specimens from 12 Fabry heterozygotes, the total glycolipid fraction was increased (10 to 100-fold) and trihexosyl ceramide (CTH) was 2- to 70-fold times normal. Digalactosyl ceramide (Digal-Cer), which is normally present in trace amounts in urine, was also increased. The ratio of CTH and Digal-Cer to hydroxy fatty acid glucosyl ceramide was increased and seemed to be characteristic of Fabry disease. This method provides rapid and accurate detection of Fabry heterozygotes.

Adolescent↗
PubMed1987

Neuropathy and IgM paraproteinemia: differential binding of IgM M-proteins to peripheral nerve glycolipids.

Two patients with neuropathy and IgM paraproteinemia displayed different immunoreactivity to acidic peripheral nerve glycolipids. In one patient, immunostaining on thin-layer chromatographic plate revealed binding of the IgM to sulfated glucuronosyl paragloboside (SGPG) and sulfated glucuronosyl lactosaminyl paragloboside (SGLPG). The other IgM bound SGPG, SGLPG, and a new third glycolipid. Immunoreactivity of the IgM varies in this syndrome.

Aged↗
PubMed1994

Visualization and quantification of glycolipid polarity dynamics in the plasma membrane of the mammalian spermatozoon.

Seminolipid (sulphogalactosylalkylacylglycerol), the glycolipid that is specific for mammalian germ cells, is located exclusively in the outer leaflet of the sperm plasma membrane. In this study the lateral distribution of seminolipid on sperm heads has been investigated by indirect immunofluorescence labelling and detection with digital imaging fluorescence microscopy. In freshly ejaculated sperm cells this glycolipid was present primarily at the apical ridge subdomain of the plasma membrane of the sperm head. After binding the sperm cells to zona-coated coverslips seminolipid migrated, in 40 minutes, from the apical ridge to the equatorial subdomain of the plasma membrane. A similar redistribution of seminolipid was observed during capacitation of sperm cells in vitro induced by Ca2+ or bovine serum albumin. Comparable migration of seminolipid was also found after prolonged storage of ejaculated sperm cells, albeit at a much slower rate. Addition of arylsulphatase A, an enzyme present in seminal plasma that desulphates seminolipid, significantly enhanced the migration of seminolipid during storage of sperm cells. Its breakdown product desulphoseminolipid (galactosylalkylacylglycerol) appeared highly specifically at the equatorial segment. The measured fluorescence intensity over the sperm head surface correlated linearly with the spatial probe distribution as was checked by fluorescence lifetime imaging microscopy. This paper demonstrates and quantifies for the first time the polarity of seminolipid on the surface of the sperm cell and the dynamic alterations that occur in this polarity during post-ejaculatory events.

Animals↗
PubMed2005

Structural characterization of complex bacterial glycolipids by Fourier transform mass spectrometry.

Bacterial glycolipids are complex amphiphilic molecules which are on the one hand of utmost importance for the organization and function of bacterial membranes, and which on the other hand play a major role in the activation of cells of the innate and adaptive immune system of the host. Already small alterations of their chemical structure may influence the biological activity tremendously. Due to their intrinsic biological heterogeneity [number and type of fatty acids, saccharide structures, and substitution with e.g. phosphate (P), 2-aminoethyl- (pyro)phosphate groups (P-Etn) or 4-amino-4-deoxyarabinose (Ara4N)], separation of the different components are a prerequisite for unequivocal chemical and NMR structural analyses. In this contribution the structural information which can be obtained from heterogeneous samples of glycolipids by Fourier transform (FT) ion cyclotron resonance mass spectrometric methods is described. By means of recently analysed complex biological samples the possibilities of high resolution electrospray ionization FT-MS are demonstrated. Capillary skimmer dissociation, as well as tandem mass spectrometry MS/MS analysis utilizing collision-induced dissociation and infrared multiphoton dissociation, are compared and their advantages to provide structural information of diagnostic importance are discussed.

Carbohydrate Sequence↗
PubMed2002

Evaluation of a commercially available serologic assay for antibodies against tuberculosis-associated glycolipid antigen.

A commercially available enzyme immunoassay developed to detect antibodies to a tuberculosis-associated glycolipid antigen was evaluated for serologic diagnosis of tuberculosis. This was a multicenter study comparing the assay with other methods in 78 patients with active pulmonary tuberculosis and in 54 controls with non-tuberculous lung diseases. Sensitivities were highest for sputum culture (91.0%), followed by immunoassay (79.5%), nucleic acid amplification (77.3%), and finally acid-fast staining of sputum smear (60.3%). Immunoassay and amplification, both rapid methods, had similarly high sensitivity in smear-positive subjects (89.4 and 88.9%, respectively); in smear-negative subjects these two techniques showed low sensitivity (64.5 and 60.0%, respectively). Concordance between the two methods was relatively low (72.0%). With regard to specificity, seven out of ten patients with old tuberculosis had positive result by immunoassay (30% specificity). In the control group, 10 out of 54 patients had positive immunoassay result (72.2% specificity), with notably limited specificity in the elderly. The tuberculous glycolipid assay is a rapid method sufficiently sensitive for detection of tuberculosis infection, even in smear-negative patients.

Adolescent↗
PubMedDate not supplied

Artificial phospholipid and glycolipid particles, visualization of their structures by fluorescence markers and some biological properties expressed by these particles.

Homogeneous large (5--30 micrometer) lipid particles comparable in size and shape to blood cells can be obtained when excess of cholesterol is homogenized with egg phospholipids or brain glycolipids in a Dounce apparatus. The particles contain distinct structures of membranes and lipid cores as visualized by the included fluorescence markers. When these particles were used as models in studying interactions between membranes, it was demonstrated that several properties normally pertaining to natural membranes could be exhibited by lipids alone. It could also be shown that particles containing phospholipids or glycolipids were very different in their adhesiveness to tissue culture cells and in their response to sera of various species.

Agglutination Tests↗
PubMed1988

Human monoclonal antibodies to phenolic glycolipid-1 from leprosy patients cross react with poly(ADP-ribose), polynucleotides and tissue bound antigens.

Antibodies which bind to poly(ADP-ribose) have been described in Systemic Lupus Erythematosus (SLE) and a variety of infectious diseases. Two IgM kappa human monoclonal antibodies (MAbs), TH3 and PR4, produced from the fusion of peripheral blood lymphocytes of leprosy patients with the GM4672 lymphoblastoid cell line, were found to bind to poly(ADP-ribose) in direct binding and inhibition ELISAs. Significant inhibition of binding of these MAbs to poly(ADP-ribose) occurred with phenolic glycolipid-1, the M. leprae specific glycolipid, ssDNA, dsDNA, poly(dT), as well as poly(ADP-ribose) itself. Up to 80% of binding of TH3, and 90% of binding of PR4, to poly(ADP-ribose) was inhibited by 10 mcg of ssDNA suggesting that there may be sharing of some conformational determinants. Although the serological binding profiles of TH3 and PR4 are similar, only PR4 was found to bind to basal keratinocytes of normal human interfollicular epidermis and astrocyte cytoplasm in normal brain tissue. These results support the concept that an antibody binding site may accommodate more than one epitope. Furthermore, small differences in antigen binding potential may distinguish relatively innocuous antibodies from those which may be more pathogenic.

Antibodies, Monoclonal↗
PubMed2002

2B4 is constitutively associated with linker for the activation of T cells in glycolipid-enriched microdomains: properties required for 2B4 lytic function.

2B4 is a receptor belonging to the Ig superfamily and is found on all murine NK cells as well as a small subset of T cells. Previous studies have found that cross-linking of the 2B4 receptor results in both increased cytotoxicity and IFN-gamma secretion. We have discovered that 2B4 from transfected NK and T cell lines, as well as from primary murine cells, coimmunoprecipitates with the phosphoprotein linker for the activation of T cells (LAT), which is essential for TCR-mediated signaling. This association is independent of both 2B4 phosphorylation and the cytoplasmic tail of 2B4. We have found that, along with LAT, 2B4 is constitutively located in glycolipid-enriched microdomains of the plasma membrane. In fact, 2B4 appears to associate with LAT only when it localizes to glycolipid-enriched microdomains. This localization of 2B4 occurs due to a CxC cysteine motif found in the transmembrane region, as determined by mutagenesis studies. 2B4-mediated cytotoxicity is defective in the absence of LAT, indicating that LAT is a required intermediate for 2B4 signal transduction. However, we have also shown that LAT association alone is not sufficient for maximal 2B4 activation.

Adaptor Proteins, Signal Transducing↗
PubMed2004

Quantitative and qualitative differences in the in vivo response of NKT cells to distinct alpha- and beta-anomeric glycolipids.

NKT cells represent a unique subset of immunoregulatory T cells that recognize glycolipid Ags presented by the MHC class I-like molecule CD1d. Because of their immunoregulatory properties, NKT cells are attractive targets for the development of immunotherapies. The prototypical NKT cell ligand alpha-galactosylceramide (alpha-GalCer), originally isolated from a marine sponge, has potent immunomodulatory activities in mice, demonstrating therapeutic efficacy against metastatic tumors, infections, and autoimmune diseases, but also has a number of adverse side effects. In vivo administration of alpha-GalCer to mice results in the rapid activation of NKT cells, which is characterized by cytokine secretion, surface receptor down-regulation, expansion, and secondary activation of a variety of innate and adaptive immune system cells. In this study, we have evaluated the in vivo immune response of mice to a set of structural analogues of alpha-GalCer. Our results show that, contrary to current thinking, beta-anomeric GalCer can induce CD1d-dependent biological activities in mice, albeit at lower potency than alpha-anomeric GalCer. In addition, we show that the response of NKT cells to distinct GalCer differs not only quantitatively, but also qualitatively. These findings indicate that NKT cells can fine-tune their immune responses to distinct glycolipid Ags in vivo, a property that may be exploited for the development of effective and safe NKT cell-based immunotherapies.

Adjuvants, Immunologic↗
PubMed2000

Analysis of circulating immune complexes (CICs) in childhood tuberculosis: levels of specific antibodies to glycolipid antigens and relationship with serum antibodies.

BACKGROUND: The presence of specific antiglycolipid antibodies in serum and circulating immune complexes (CIC) in children with tuberculosis was detected in order to evaluate their contribution to the value of serodiagnosis of tuberculosis, as has already been shown in adults. METHODS: ELISAs using the three glycolipids LOS, DAT and PGLTb1 were performed in whole serum and immune complexes from 20 children with tuberculous disease or infection, in seven child contacts, and in 26 children with non-tuberculous disease. The contribution of complexed IgG antibody to the diagnostic values was established for each group. RESULTS: The antibody levels in free serum were higher (P < 0.01) in children with tuberculous disease or infection and in contacts than in controls. By contrast, except for PGLTb1, the IgG antibody levels were higher (P < 0.02) in children with tuberculous disease than in the other groups. The highest contribution of IgG antibody against LOS to the predictive values was shown in children with pulmonary tuberculosis (positive predictive value 1,000, negative predictive value 1,000). In paucibacillary tuberculosis (extra-pulmonary and tuberculous infection) and in contacts, the IgG antibody did not contribute to the sensitivity of the serodiagnosis, where the combination of antigens tested in serum increased the diagnostic yield. The very low levels of IgG antibody in these settings may indicate a different B cell response. CONCLUSION: The detection of immune complexes and IgG antibodies against the three glycolipid antigens is useful as a complementary technique for the serodiagnosis of children with a high probability of pulmonary tuberculosis.

Adolescent↗
PubMedDate not supplied

Immunity to glycolipid antigens in microbial infections.

T cells recognize ligands of different chemical structures. Recently, it has become clear that also self glycosphingolipids and bacterial lipoglycans may act as T cell stimulatory ligands. This type of antigen recognition is restricted by the non-polymorphic CD1 molecules, which have a structure resembling that of classical MHC molecules. Glycolipids insert their hydrophobic lipid tails in two pockets below the antigen-binding groove and position their hydrophilic heads on the external part of CD1 molecules. TCR interacts with these carbohydrates and discriminates their structural variations. Glycolipid-specific T cells may provide protection during bacterial and parasite infection probably with different mechanisms: by secreting pro-inflammatory lymphokines, by the direct killing of infected target cells, and by helping specific B cells in Ig production. Lipoglycans represent excellent candidates for new anti-microbial vaccines due to their wide distribution in the microbial world and their structural composition which does not change and thus cannot give rise to escape mutants. Moreover, these vaccines might induce anti-microbial protective T cell responses in the whole population due to the non-polymorphic nature of CD1 presenting molecules.

Animals↗
PubMed2002

Production of glycolipids containing biosurfactant by Pseudomonas species.

Microorganisms, that degrade hydrocarbon were isolated and screened for their biosurfactant activity. A total of 68 strains were isolated and tested for their glycolipid activity of which 4 isolates showed good glycolipid activity. Isolate K10 gave the maximum biosurfactant production in medium A (containing kerosene as a sole carbon source) as compared to medium B (containing glucose as a sole carbon source). Characterization of isolate K10 showed that it belongs to Pseudomonas species.

Biodegradation, Environmental↗
PubMed1992

Oligodendrocytes lack glycolipid anchored proteins which protect them against complement lysis. Restoration of resistance to lysis by incorporation of CD59.

Rat oligodendrocytes, which activate the classical pathway of complement in the absence of antibody, are highly sensitive in a reactive lysis assay using human C5b6 and EDTA serum. Oligodendrocytes may be relatively deficient in glycolipid-linked complement regulatory protein(s), since digestion with phosphatidylinositol-specific phospholipase C (PI-PLC) failed to increase their sensitivity to serum, whereas complement-insensitive astrocytes, when treated with PI-PLC, became strikingly sensitive. To test the hypothesis that oligodendrocytes lack terminal complement regulatory molecule(s), human erythrocyte CD59, a recently described complement regulatory protein, was purified to homogeneity. The biological activity of the preparation was confirmed by reincorporating the protein into guinea-pig erythrocytes through its glycolipid anchor, which resulted in dose-dependent protection against human C5b6 and EDTA serum. Incorporation of 10(5) molecules of human CD59 into rat oligodendrocytes resulted in good protection against homologous human complement (76%), and significant protection against rat complement homologous to the cell (36%). Protection could be reversed using an antibody to CD59.

Animals↗
PubMed2004

[Anti-endotoxin core glycolipid antibody: the preparation of immune serum of E. Coli J5].

OBJECTIVE: To prepare high titer anti-endotoxin core glycolipid (J5) antibody (CGL) for the treatment of Gram-negative bacteremia and septic shock. METHODS: Nontoxic bacterial vaccine (50 x 10(12)U/L) against E.Coli O111:B4 mutant strain J5 was prepared. J5 bacterial vaccine was injected into rabbits through ear marginal vein (saline as control preparation), one time pre three days, totally five times. Injected doses were as following: 0.1 ml, 0.2 ml, 0.4 ml, 0.6 ml, and 0.8 ml. One week after fifth injection, blood samples from heart were collected and immune serum was isolated. Indirect clotting test was used to determine the titer of antibody and cross reaction. RESULTS: Among 12 immunized rabbits, titers of antibody against E. Coli J5 were exceeding 1:1 024 in 6 rabbits, and they had cross reaction with various kinds of Gram-negative bacterial endotoxins. CONCLUSION: The titer of anti-endotoxin core glycolipid (E.Coli J5) antibody prepared by us appears to be high, and it can combine with various kinds of Gram-negative bacterial endotoxins.

Animals↗
PubMedDate not supplied

[The fungicidal activity of an extracellular glycolipid from Sympodiomycopsis paphiopedili sugiyama et al].

The yeast Sympodiomycopsis paphiopedili (Ustilaginomycetes) produces an extracellular glycolipid, which possesses the maximum antifungal activity at the pH of the medium equal to 4.0-4.5. Among the approximately 300 tested species of yeastlike and mycelial fungi, more than 80% (including species pathogenic for plants, animals, and humans) were found to be susceptible to this glycolipid.

Antifungal Agents↗
PubMedDate not supplied

[CD1 pathway and NK T cell activation to glycolipid antigens from Mycobacterium tuberculosis].

The aim of this review is to analyze the current state of our knowledge about cell surface molecules involved in glycolipid antigen presentation, named CD1 family. These proteins constitute a third class of antigen-presenting molecules. CD1 molecules develop diverse important immune functions in host defenses against microbial infections. In recent years these proteins have been involved in the generation of cell-mediated immune response against Mycobacterium tuberculosis. Here, we analyze relevant roles of CD1 proteins and glycolipid antigen-specific T cells.

Antigens, Bacterial↗
PubMed1992

Specificity of lung surfactant protein SP-A for both the carbohydrate and the lipid moieties of certain neutral glycolipids.

Binding specificity of the major surfactant protein SP-A from human and dog lung has been investigated. Radiobinding experiments have shown that both proteins bind in a Ca(2+)-dependent manner to galactose, mannose, fucose, and glucose linked to bovine serum albumin. These results are in accord with a previous study in which monosaccharides were linked to agarose (Haagsman, H. P., Hawgood, S., Sargeant, T., Buckley, D., White, R. T., Drickamer, K., and Benson, B. J. (1987) J. Biol. Chem. 262, 13877-13880). Chromatogram overlays in conjunction with in situ liquid secondary ion mass spectrometry (TLC-LSIMS) of several purified glycosphingolipids and neoglycolipids as well as binding assays with glycolipids immobilized on plastic wells, demonstrate recognition of galactose (human and dog SP-A), glucose, and lactose (human SP-A) in association with specific lipids. In addition, the occurrence of several neutral and acidic glycosphingolipids in human and rat extracellular surfactants and rat alveolar type II cells is described. Selected components among the neutral glycolipids are bound by radiolabeled human SP-A; these are identified by TLC-LSIMS as predominantly ceramide mono- and disaccharides (human surfactant) and ceramide tri- and tetrasaccharides (rat surfactant and type II cells). A recombinant carbohydrate recognition domain (CRD) of human SP-A inhibits the binding of human SP-A to galactosyl ceramide and to galactose- and mannose-bovine serum albumin, indicating that the CRD is directly involved in the binding of SP-A to these ligands. These results provide evidence for a novel type of binding specificity for proteins that have Ca(2+)-dependent CRDs and raise the possibility that glycosphingolipids are endogenous ligands for SP-A.

Animals↗