Liposome gangliosides

Amount Added (nanomoles) Liposomes Gangliosides Liposomal Gangliosides... 

TABLE 5 Binding Constant, AT, for the Interaction Between the Liposomal Ganglioside and the Bulk Polysaccharide (Dextran-40) in the Aqueous 4.0% (w/w) PEO-20/8.0% (w/w) Dextran-40 System at 24 C... 

Materials. Egg phosphatidylcholine (PC), bovine brain phosphatidylserine (PS) were obtained from Avanti Polar Lipids Inc. (Birmingham, AL) and cholesterol was from Sigma (St. Louis, MO). Ganglioside GMj, bovine, was obtained from Calbiochem (San Diego, CA). Diethylenetriamine pentaacetic acid distearylamide complex (DPTA-SA) was synthesized according to ref. 17 and nlIn-DTPA-SA was prepared as described (7). This lipophilic radiolabel is not transferred to the serum components from liposomes (unpublished data), nor is it rapidly metabolized in vivo (7). The synthesis of N-(glutaryl)phosphatidylethanolamine(NGPE) has been described (18). Dipalmitoyl deoxyfluorouridine(dpFUdR) was synthesized as described (24). 

Goins B, Ligler FS, Rudolph AS. Inclusion of ganglioside GMl into liposome encapsulated hemoglobin does not extend circulation persistence at clinically relevant doses. Artif Cells Blood Substit Immobil Biotechnol 1994 22 9. 

In both of these cases, the ligand (sialic acid) for the analyte of interest (influenza vims) was covalently linked to the PDA backbone generated upon photopolymerization. Functional sensors based on ligands that are noncovalently incorporated into liposomes have also been reported (Charych et al. 1996 Pan and Charych 1997). Mixed liposomes as well as mixed thin films on glass containing a combination of the ganglioside GMl and diacetylene lipids detect the presence of cholera toxin, a protein that binds to GMl. 

This cooperative effect of several ligands at the surface of a liposome was recently demonstrated by the inhibition of agglutination of erythrocytes (natural vesicles covered with sialic acids) with the influenza virus by means of sialyl gangliosides. The lowest concentration of sialyl derivatives required for the inhibition was found to be 10 pM in solution whereas it was 20 nM at the surface of a vesicle. Actually, arrays of sialic acid at the surface of liposomes were found to be moderately more effective than sialic acid groups linked to a soluble polymer but as good or better than the best known naturd inhibitors of hemagglutination (i.e. mucins and macroglobulins) [150]. 

Prepare a 5 mg/ml liposome construction in 20 mM sodium phosphate, 0.15 M NaCl, pH 7.4, containing, on a molar ratio basis, a mixture of PC cholesterol PG other glycolipids of 8 10 1 2. The other glycolipids that can be incorporated include phosphatidyl inositol, lactosylceramide, galactose cerebroside, or various gangliosides. Other liposome compositions may be used, for example, recipes without cholesterol, as long as a periodate-oxidizable component... 

Table VI. Binding of Choleragen to Liposomes Containing Gangliosides ...

Figure 3. Physicochemical features of mixed aggregates of phosphatidylcholine, phosphatidylethanolamine (PE, used as surface marker), and gangliosides (Gut, G ,a, GTlb, Gt),b) at increasing proportions of ganglioside. Highest value of the outer PE/total PE ratio corresponds to liposomes. Lowering of turbidity and concurrent enhancement of ratio indicate presence of micelles. Break point is indicated as the transition ganglioside/ phospholipid molar ratio. ...

Figure 12. Time course of NeuAc release from liposome-associated ganglioside Gn,a by the action of Vibrio cholerae sialidase...

Figure 13. Time course of oxidation of the terminal galactose residue of liposome-associated ganglioside G.VI by the action of galactose oxidase...

Sendai virus, like other myxo- and paramyxovirus, has surface glycoprotein spikes which adsorb to specific receptors on erythrocytes of most mammalian and fowl species and cause hemagglutination. The receptors on erythrocyte membranes contain neuraminic acid, as indicated by the fact that they are destroyed by neuraminidase. Haywood (3 ) demonstrated that liposomes containing gangliosides could inhibit the agglutination of erythro-... 

The data presented in Table I demonstrate the effects of gangliosides, liposomes, and gangliosides incorporated into lipo-... 

The data presented in Table XII show the effects of exogenous gangliosides, liposomes, and liposomal-bound gangliosides when added at initiation of MLC and 48 and 96 hours later. The effects of gangliosides on MLC reactivity with respect to the time of addition were similar to the effects on Con-A reactivity. When added at the time of culture initiation, both gangliosides and liposomal-bound gangliosides resulted in maximal inhibition with less effect noted when added 48 hours and 96 hours later. 

Comparison of the Effects of Gangliosides. Liposomal-Bound Gangliosides, and Liposomes Added at Various Time Intervals on - H-Thymidine Incorporation (CPMxlO J) Into PBMC in Mixed Leukocyte Cultures... 

Figure 5. Natural antibodies in normal human and rabbit sera against liposomes containing gangliosides GM1 or Gntb. Glucose release measured from liposomes containing DMPC, CHOL, DCP, and GM, (150 /lg/fimol PC) or G,)tb (150 fig/p/riol PC). Human serum was complement source with the GM, liposomes due to high level of anti-Gui activity in guinea pig serum (1).

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