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PubMed1998

pH-independent retrograde targeting of glycolipids to the Golgi complex.

A small fraction of the molecules internalized by endocytosis reaches the Golgi complex through a retrograde pathway that is poorly understood. In the present work, we used bacterial toxins to study the retrograde pathway in Vero cells. The recombinant B subunit of verotoxin 1B (VT1B) was labeled with fluorescein to monitor its progress within the cell by confocal microscopy. This toxin, which binds specifically to the glycolipid globotriaosyl ceramide, entered endosomes by both clathrin-dependent and -independent pathways, reaching the Golgi complex. Once internalized, the toxin-receptor complex did not recycle back to the plasma membrane. The kinetics of internalization and the subcellular distribution of VT1B were virtually identical to those of another glycolipid-binding toxin, the B subunit of cholera toxin (CTB). Retrograde transport of VT1B and CTB was unaffected by addition of weak bases in combination with concanamycin, a vacuolar-type ATPase inhibitor. Ratio imaging confirmed that these agents neutralized the luminal pH of the compartments where the toxin was located. Therefore, the retrograde transport of glycolipids differs from that of proteins like furin and TGN38, which require an acidic luminal pH. Additional experiments indicated that the glycolipid receptors of VT1B and CTB are internalized independently and not as part of lipid "rafts" and that internalization is cytochalasin insensitive. We conclude that glycolipids utilize a unique, pH-independent retrograde pathway to reach compartments of the secretory system and that assembly of F-actin is not required for this process.

Animals↗
PubMed1997

Microbial extracellular glycolipid induction of differentiation and inhibition of the protein kinase C activity of human promyelocytic leukemia cell line HL60.

The biological activities of 7 microbial extracellular glycolipids including mannosylerythritol lipid (MEL)-A, MEL-B, polyol lipid (PL), rhamnolipid (RL), sophorose lipid (SL), succinoyl trehalose lipid (STL)-1, and STL-3 were investigated. All glycolipids except for RL were found to induce cell differentiation instead of cell proliferation in the human promyelocytic leukemia cell line HL60. To identify the differentiation direction of the induced cells, the leukocyte esterase activities were cytologically investigated, and the results showed that MEL-A, MEL-B, and PL induced HL60 to differentiate into granulocytes, while SL, STL-1, and STL-3 induced differentiation into monocytes. The 6 effective glycolipids also increased nitroblue tetrazolium (NBT) reducing ability, which is a common differentiation-associated characteristic in monocytes and granulocytes. Furthermore, it was also observed that these 6 glycolipids inhibited the activity of phospholipid- and Ca(2+)-dependent protein kinase. Additionally, the 6 effective glycolipids also induced the human myelogenous leukemia cell line K562 and the human basophilic leukemia cell line KU812 to differentiate into monocytes, granulocytes, and megakaryocytes.

Cell Differentiation↗
PubMed1988

Binding of cytoplasmic islet cell antibodies is blocked by human pancreatic glycolipid extracts.

With biochemical and enzymatic treatment of frozen sections of pancreas, we have previously shown that cytoplasmic islet cell antibodies (ICAs) react with carbohydrate determinants of islet cell glycoconjugates. As a first step toward purifying these glycoconjugates, human pancreas tissue was extracted in a mixture of chloroform and methanol, and the glycolipids were obtained by effecting a Folch partition. The protein pellet, lipid fraction, and glycolipid fraction so obtained were assessed for their ability to block the binding of ICAs to frozen sections of human pancreas, the effect being quantitated with a photometer. Only the glycolipid extract could block ICA binding, and blocking was dose dependent. Subfractionation of the glycolipid extract by hydrophobic interaction on C18 cartridges demonstrated that blocking activity resided in the fraction bound and eluted with methanol, consistent with the autoantigen being a glycolipid. Furthermore, the binding of an anti-islet cell ganglioside monoclonal antibody, 3G5, could be blocked with these extracts, whereas the binding of an anti-islet cell protein monoclonal antibody, 4F2, was unaffected. The major gangliosides of the pancreas were seen to be GM3 and GD3 by thin-layer chromatography (TLC). Fractions scraped and eluted from TLC plates were tested for their ability to block ICA binding to pancreatic sections. Neither GM3- nor GD3-containing fractions could block ICA binding; however, a fraction containing minor pancreatic gangliosides (including GM2) of monosialoganglioside mobility was a potent inhibitor of ICA binding to pancreas sections. TLC of a chloroform-methanol extract of human islets demonstrated that islets differentially express monosialogangliosides (especially GM2).

Antibodies↗
PubMed1998

Interaction of mycobacterial glycolipids with host cells.

Mycobacteria elaborate a great variety of glycolipids of rather exotic structure. Some of these lipids are abundant cell envelope components and are exposed on the bacterial surface. These comprise the species-specific phenolic glycolipids, glycopeptidolipids, sulfatides, and lipooligosaccharides, and the ubiquitous phosphatidylinositolmannosides. Because pathogenic mycobacterial species are facultative intracellular parasites that infect and reside in host cells, some of them may represent potential virulent factors as they have been shown to inhibit both macrophage antimicrobial activities and lymphoproliferation. These biologic activities may derive, at least in part, from the modulation of the cell functions through the interactions between host membranes and these surface-exposed lipids whose structures are different from those of mammalian cell membrane components. In few cases purified glycolipids have been shown to profoundly affect the physical and functional properties of biologic membranes. Therefore, the enzymes involved in the biosynthesis of the biologically active glycolipids represent potential drug targets. However, definite proofs of their implication in the mycobacterial pathogenicity are lacking. Mutants unable to elaborate defined glycolipids are needed.

Animals↗
PubMed1994

Double-tailed perfluoroalkylated glycolipids as components for drug delivery and targeting systems. Preliminary biocompatibility results.

Vesicles are being investigated as drug carriers, especially for enhancing the therapeutic effectiveness of the drug while minimizing its side effects. Drug targeting can be achieved if there is a specific recognition of the vesicle's outer wall by specific cells. With these objectives in mind new glycolipids fitted with fluorinated, hydrogenated or mixed, single and double-tails, containing either a gluco- or a galactopyranose residue in their hydrophilic head, were synthesized and their ability to achieve self-organized supramolecular systems was assessed. Replacement of hydrogen by fluorine in these glycolipids was found to enhance biological tolerance. Thus, a fluorinated single-tailed glycolipid displayed no action on red blood cells at concentrations as high as 50 g/l while its hydrogenated analog was hemolytic at 5 g/l. 100% of survival was obtained one month after intravenous or intraperitoneal injection into mice of isotonic dispersions of single and double-tailed glycolipids at a dose of 500 mg/kg. These glycolipids were innocuous on Namalva cell cultures at a concentration of 0.1 g/l.

Alkylation↗
PubMed2001

Beneficial effect of dietary wheat glycolipids on cecum short-chain fatty acid and secondary bile acid profiles in mice.

In the present study, to explore the beneficial effect of dietary galactoglycerolipids on the lower digestive tract environment, male BALB/c mice were fed a 5% wheat glycolipid, fiber-free diet, or the standard AIN diet for 3 wk. The wheat glycolipid composition was digalactosyldiacylglycerol 51.6%, ceramide monohexoside 6.6%, acylated sterylglucoside 3.4%, and other lipids 22.2%, (mostly phospholipids). Cecum and colon weights and colonic crypt depth were significantly greater in the glycolipid-diet mice relative to groups fed the other two diets. Furthermore, in the cecum, propionate. butyrate, and total short-chain fatty acids, concentrations were significantly greater in the glycolipid-diet mice than others were, and correlated with the observed increased lower digestive tract (cecum and colon) weights and colonic crypt depth. The cecal lithocholic acid/deoxycholic acid ratio, a risk index for colorectal cancer, was significantly lower in the glycolipid-diet mice than in the other two dietary groups. These results suggest that the dietary supplementation of plant-source galactoglycerolipids may contribute to improving the lower digestive tract environment.

Animals↗
PubMed1998

Granuloma formation and in vitro macrophage activation in mice by mycoloyl glycolipids from Nocardia asteroides and related taxa.

Cord factor (trehalose 6,6'-dimycolate: TDM) is a well-known toxic glycolipid in Mycobacterium tuberculosis. We isolated various mycoloyl glycolipids from Nocardia asteroides 23,167 and related species which are closely related taxonomically to Mycobacterium. Since Nocardia is also an opportunistic pathogen co-infected with HIV, we examined in vivo granuloma formation and the in vitro macrophage activation in mice. We found that cord factor (TDM) and glucose monomycolate (GM) from Nocardia asteroides and Rhodococcus species with shorter chain mycolic acids also exhibited distinctive granuloma-forming activity in lungs, spleen and liver in mice and in vitro induction of prostaglandin E2 (PGE2) and interleukin 1 (IL-1) synthesis. We also found that mycoloyl glycolipids possessing trehalose or glucose as a carbohydrate moiety exhibited immunomodulatory activity, and that mycoloyl glycolipids with longer chain mycolic acids exhibited stronger activity in mice than did those with shorter chain mycolic acids. The mycoloyl glycolipids from Nocardia asteroides directly activated macrophages. Stimulation of above concentration with 0.16 microgram/ml of TDM or 0.8 microgram/ml of GM markedly enhanced production of PGE2 by mouse peritoneal macrophages. At higher concentrations above 100 micrograms/ml of TDM or 500 micrograms/ml of GM, IL-1 release was also enhanced.

Animals↗
PubMed2005

Inhibitory effect of glycolipids from spinach on in vitro and ex vivo angiogenesis.

Anti-cancer activity of some glycolipids from animals and plants has been demonstrated, although it was unknown whether the glycolipids had anti-angiogenic activity. The effects of the purified three glycolipids, monogalactosyl diacylglycerol (MGDG), digalactosyl diacylglycerol (DGDG), and sulfoquinovosyl diacylglycerol (SQDG) from the green vegetable spinach (Spinacia oleracea L.) were examined on in vitro and ex vivo angiogenesis models. MGDG and SQDG suppressed microvessel growth in an ex vivo angiogenesis model using a rat aortic ring. The glycolipids inhibited human umbilical vein endothelial cell (HVUEC) tube formation on a reconstituted basement membrane and HUVEC proliferation. These results demonstrate that glycolipids from spinach would suppress tumor growth by suppressing angiogenesis and might be candidates for anti-cancer or anti-angiogenic materials.

Angiogenesis Inhibitors↗
PubMedDate not supplied

[Isolation and comparative analysis of glycolipid fractions in bifidobacteria].

A comparative TLC analysis of lipid extracts from Bifidobacterium longum B 379 M, B. bifidum 791, and B. adolescentis 94 BIM has been performed. It is demonstrated that carbohydrate-containing lipid components were present in the bacteria, which differed in their chromatographic mobility (Rf) from similar compounds isolated from actinomycetes Stomatococcus mucilaginosus PCM 2415T, Nocardiopsis dassonvillei PCM 2492, Propionibacterium propionicum PCM 2431, Saccharopolyspora hirsuta PCM 2279 (= ATCC 27875T), Rhodococcus equi PCMT 559 (= ATCC 3969), and Gordonia bronchialis PCM 2167. Polar lipids of bifidobacteria exhibited the closest similarity to their counterparts from propionic acid bacteria. Preparative chromatography (silica gel column I; elution with chloroform, acetone, and methanol) of the lipid extract of B. adolescentis 94 BIM made it possible to isolate fractions containing nonpolar lipids, glycolipids, and phospholipids. Further purification of the glycolipid fraction (column II; eluant, methanol gradient in chloroform) produced preparations of glycolipids and phospholipids. The preparations were studied by two-dimensional TLC using solvent systems chloroform-methanol-H2O MiLi Q (65 : 25 : 4, v/v/v) and n-butanol-acetic acid-H2O MiLi Q (60 : 20 : 20, v/v/v) for directions I and II, respectively. Two major glycolipids were revealed (G1 and G2), in addition to compounds characteristic of the polar lipid group and minor glycolipids (g), the latter being present in considerably lesser amounts.

Bifidobacterium↗
PubMed1990

Cell-free synthesis of glycosyl-phosphatidylinositol precursors for the glycolipid membrane anchor of Trypanosoma brucei variant surface glycoproteins. Structural characterization of putative biosynthetic intermediates.

Trypanosome variant surface glycoproteins exemplify a class of eukaryotic cell surface glycoproteins that rely on a carboxyl-terminal covalently-attached inositol-containing glycophospholipid for membrane attachment. The glycolipid anchor is acquired soon after translation of the polypeptide, apparently by replacement of a short carboxyl-terminal peptide sequence with a prefabricated glycolipid. A candidate glycolipid precursor (referred to as P2), and a related glycolipid (P3) have been identified recently in polar lipid extracts from trypanosomes. In this paper we describe the synthesis of P2 and P3 by trypanosome membranes. Analyses of organic solvent extracts from membranes incubated with radioactive sugar nucleotides (GDP-[3H]mannose or UDP-[3H]GlcNAc) showed a spectrum of labelled lipids, ranging from partially glycosylated species to the final products, P2 and P3. Structural analyses of these putative biosynthetic intermediates suggest that glycolipid assembly occurs via the sequential glycosylation of phosphatidylinositol.

Animals↗
PubMed2007

Structure-activity relationship of a glycolipid, sulfoquinovosyl diacylglycerol, with the DNA binding activity of p53.

The in vitro relationship between the human p53 DNA binding domain (p53 DBD) and glycolipids was investigated. We isolated the glycolipid fraction from spinach (Spinacia oleracea L.) and found that the fraction inhibited the double-stranded DNA (dsDNA) binding activity of p53 DBD. Since the fraction contained mainly three glycolipids, monogalactosyl diacylglycerol (MGDG), digalactosyl diacylglycerol (DGDG) and sulfoquinovosyl diacylglycerol (SQDG), and each glycolipid was purified using silica gel column chromatography. Purified SQDG inhibited the activity, however, purified MGDG and DGDG had no influence. In this study, we demonstrated the structure-function relationship between chemically synthetic SQDG and p53 DBD. The major action is probably dependent on the fatty acid effect, although SQDG was a much stronger inhibitor than the fatty acid alone present in SQDG. The inhibitory activity of SQDG was weakened by the R248A mutant of p53 DBD, suggesting that R248 in the dsDNA binding site of p53 must be important for the inhibitory activity of SQDG. SQDG binding to p53 DBD could be reversed with a non-ionic detergent, Nonidet P-40. This is the first study of a glycolipid, SQDG, acting as a dsDNA binding inhibitor of p53, and it could be considered that a SQDG-containing thylakoid membrane in plant chloroplasts might regulate the activity of p53 for cell division, cell cycle checkpoint and tumor suppression.

Computer Simulation↗
PubMed1978

Comparative study on glycolipid composition between two cell types of rat ascites hepatoma cells.

A comparative study of the glycolipids was performed on two cell lines of rat ascites hepatomas, island-forming and free cell types, and several marked differences were found as follows: 1. Hexose content in glycolipids derived from AH 7974F (free cell type) was about 3.6-fold as much as that from AH 7974 (island-forming cell type) on the basis of dry cell weight. 2. The glycolipids in the cells of AH 7974 were tentatively identified as glucosylceramide, lactosylceramide, galactosylgalactosylglucosylceramide, globoside and hematoside (GM3) by both thin-layer and gas-liquid chromatography. 3. On the other hand, the glycolipids in AH 7974F cells were glucosylceramide, lactosylceramide and at least four unknown lipids. 4. Structure of one of these unknown lipids was shown to be asialo-GM2 by methylation and enzymatic degradation studies. Moreover, the presence of asialo-GM1 was suggested by immunoprecipitation test with anti-asialo-GM1 serum. 5. Glucosylceramide and lactosylceramide from AH 7974F cells were found to possess hydroxy fatty acids as major fatty acids components, which were rare in these glycolipids from AH 7974 cells.

Animals↗
PubMed1990

Lacto- and ganglio-series glycolipids are adhesion receptors for Neisseria gonorrhoeae.

The role of glycolipids as adhesion receptors for Neisseria gonorrhoeae is examined. Serum-resistant isolates, piliated and nonpiliated isogenic variants, as well as gonococci deficient in lipooligosaccharide and protein II, bind specifically to terminal and internal GlcNAc beta 1-3Gal beta 1-4Glc and GalNAc beta 1-4Gal beta 1-4Gcl sequences in lacto- and ganglio-series glycolipids, respectively, as measured by overlaying glycolipid chromatograms with 125I-labeled organisms. The binding activity was not affected by changing the growth conditions of the organism, as the gonococci bound to both classes of glycolipids when grown anaerobically, microaerophilically on agar or in broth, or under iron-limited conditions. The gonococci do not bind to lacto-sylceramide (Gal beta 1-4Glc beta 1-1Cer) derived from lacto-N-triaosylceramide or from asialo-GM2 by treatment with N-acetyl-beta-hexosaminidase, or to other neutral glycolipids tested. Although N. gonorrhoeae bound weakly to some gangliosides on thin-layer chromatograms, including sialylparagloboside and GM1, in solid phase assays the gonococci bound with high avidity to the sequence GalNAc beta 1-4Gal beta 1-4Glc, with moderate avidity to the sequence GlcNAc beta 1-3Gal beta 1-4Glc, and not at all to gangliosides. Interestingly, the 4.8-kDa component of gonococcal lipooligosaccharide, which contains lacto-N-neotetraose (Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc), strongly inhibits gonococcal-specific agglutination of human erythrocytes and inhibits the binding of labeled organisms to human paragloboside and lacto-N-triaosylceramide on thin-layer chromatograms. Possibly, this binding specificity explains why gonococci autoagglutinate in vitro.

Antibodies, Monoclonal↗
PubMed1989

Analysis of autoantibodies to glycolipids on thymocytes in New Zealand black mice.

Carbohydrate specificities of thymocyte cytotoxic autoantibodies in New Zealand Black (NZB) mice were examined using liposome immune lysis assay (LILA) system. NZB mice progressively produced antibodies to nine neutral glycolipids and two gangliosides tested by 10 months of age. Such increases were not detected in normal BALB/c and CBA/J mice. Among these antibodies, antibodies to ceramide monohexoside (CMH), ceramide dihexoside (CDH), paragloboside (PG), ceramide pentahexoside (CPH), asialo GM1 (GA1), asialo GM2 (GA2), GM4 and GM2 in the plasma of NZB mice were absorbed by single cell suspensions of autologous untreated as well as protease-treated thymocytes. In contrast, antibodies to ceramide trihexoside (CTH), globoside (Glo), and Forssman antigen (For) were not absorbed by these cells. Analysis of glycolipid compositions of young NZB thymocytes demonstrated that strict correlation was observed between the presence of glycolipids on thymocytes and absorbing pattern of anti-glycolipid antibodies by thymocytes. These data indicate that anti-carbohydrate antibodies with thymocyte binding capacity in NZB mice mainly recognize sugar portions of glycolipids rather than glycoproteins on thymocytes. The failure to find such carbohydrate specific antibodies in some normal strains of mice suggested that these antibodies may be important for subsequent immunologic abnormalities in NZB mice.

Animals↗
PubMed1987

Synthesis of type 1 and 2 lacto series glycolipid antigens in human colonic adenocarcinoma and derived cell lines is due to activation of a normally unexpressed beta 1----3N-acetylglucosaminyltransferase.

Human colonic adenocarcinoma tissue and derived cell lines have been characterized by an abundance of different type 1 and 2 lacto series glycolipid antigens which are either low or not found in normal colonic mucosa. The enzymatic basis for the expression of contrasting glycolipid compositions between adenocarcinomas and normal colonic mucosa, as well as between derived cell lines, has been studied. The following results were of particular interest. (i) Abundant activities of beta 1----4galactosyltransferase associated with synthesis of both lactosylceramide and lactoneotetraosylceramide, beta 1----3galactosyltransferase for synthesis of lactotetraosylceramide, and an alpha 1----3/4fucosyltransferase responsible for synthesis of Lex and Lea antigens were found in normal colonic mucosa or in a normal mucosal epithelial cell line HCMC, or in both. Variable levels of these activities were found in adenocarcinoma tissues and in various established adenocarcinoma cell lines. In striking contrast, significant activity of a beta 1----3N-acetylglucosaminyltransferase responsible for synthesis of lactotriaosylceramide (Lc3) was found in various cases of colonic adenocarcinoma and cell lines, but was undetectable in normal colonic epithelial cells. (ii) In situ transfer of galactose to Lc3 was performed on histologic sections by preincubation of the tissue with acceptor glycolipid followed by incubation with UDP-galactose. The biosynthesized glycolipid was revealed by indirect immunofluorescence with the monoclonal antibody 1B2 which defines lactoneotetraosylceramide antigen. In these studies, histologic sections prepared from frozen normal proximal colon tissue were shown to lack native type 2 chain structures. However, transfer of galactose from UDP-galactose could be demonstrated in the epithelial cells of normal proximal colon after incorporation of Lc3 into the membranes, indicating the ability of normal colonic epithelial cells to synthesize type 2 chain core structures if the precursor Lc3 is available. In contrast, adenocarcinoma tissues showed significant native immunofluorescence with the antibody. These data suggest that an accumulation of both type 1 and 2 chain lacto series glycolipids with alpha 1----3- or alpha 1----4fucosyl substitution in human adenocarcinoma is due to enhanced beta 1----3N-acetylglucosaminyltransferase rather than enhancement of other enzymes. This enzyme may play a key role in regulating the level of various types of lacto series tumor-associated antigens with the lacto type 1 or 2 chain.

Adenocarcinoma↗
PubMed1985

Purification and some properties of the glycolipid transfer protein from pig brain.

A glycolipid-specific lipid transfer protein has been purified to apparent homogeneity from pig brain post-mitochondrial supernatant. The purified protein was obtained after about 6,000-fold purification at a yield of 19%. Evidence for the homogeneity of the purified protein includes the following: (i) a single band in acidic gel electrophoresis, in sodium dodecyl sulfate-gel electrophoresis, (ii) a single band in analytical gel isoelectric focusing, (iii) exact correspondence between the glycolipid transfer activity and stained protein absorbance in the acidic gel electrophoresis, and (iv) coincidence between the transfer activity and protein absorption at 280 nm in gel filtration through Ultrogel AcA 54. The protein has an isoelectric point of about 8.3 and a molecular weight of 22,000, as measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A molecular weight of 15,000 was calculated from AcA 54 gel filtration. The amino acid composition has been determined. The protein binds [3H]galactosylceramide but not [3H]phosphatidylcholine. Under the conditions used, 1 mol of the transfer protein bound about 0.13 mol of [3H]galactosylceramide. The glycolipid transfer protein-[3H]galactosylceramide complex was isolated by a Sephadex G-75 chromatography. An incubation of the complex with liposomes resulted in the transfer of [3H]galactosylceramide from the complex to the acceptor liposomes. The result indicates that the complex functions as an intermediate in the glycolipid transfer reaction. The protein facilitates the transfer of [3H]galactosylceramide from donor liposomes to acceptor liposomes lacking in glycolipid as well as to acceptor liposomes containing galactosylceramide.

Amino Acids↗
PubMed1985

Immunogenic properties of glycolipids of Nocardiopsis dassonvillei.

Two specific glycolipids identified as monomannosyl diglyceride (G1) and monoacylated glucose (G2), isolated from Nocardiopsis dassonvillei strains, were found to be biologically active. They elicited antibody response in rabbits when administered with some carrier components: lecithine, methylated bovine serum albumin (MBSA) and Freund incomplete adjuvant (FIA). Antibodies to the glycolipids were detected in antisera to G1 and in the sera against crude cell antigen of N. dassonvillei (N). The ability of the lipids to induceskin delayed hypersensitivity (SDH) as well as adjuvant and mitogenic effect were also studied. Generally glycolipid G1 seemed to be more active in antibody response whereas glycolipid G2 was a better stimulator of cellular response. Glycolipid G2 appeared to be distinct adjuvant and mitogenic factor.

Actinomycetales↗
PubMed1979

Immunochemical studies of lipids. V. Effect of modified hydrophobic moiety on immunogenicity and immunologic reactivity of Forssman glycolipid.

The role of hydrophobic moiety in determining the immunologic properties of glycolipid haptens was studied with the derivatives of Forssman glycolipid modified by ozonolytic cleavage of double bonds in hydrocarbon chains. The immunogenicity was not affected by this modification; comparable antibody responses were elicited in rabbits immunized with intact or modified Forssman glycolipid, regardless of its different hydrophobicity, in complete Freunds adjuvant. Modified hydrophobic portions did not affect the class and specificity of antibodies produced. On the other hand, immunologic reactivity was strongly influenced by hydrophobic moiety; the ability to form immune precipitates with antibodies decreased as the hydrophobicity of glycolipid decreased. The reactivity in complement fixation and hemolysis inhibition tests also showed parallel decreases, though the addition of auxiliary lipids greatly reduced these differences in reactivity. The results indicate the different influences of hydrophobic moiety of glycolipids on their immunogenicity and immunologic reactivity in vitro.

Animals↗