Muramyl Tripeptide-Phosphatidyl Ethanolamine Encapsulated in Liposomes (L-MTP-PE) in the Treatment of Osteosarcoma

Author(s):  
Paul A. Meyers
1963 ◽  
Vol 09 (01) ◽  
pp. 164-174 ◽  
Author(s):  
Albert R Pappenhagen ◽  
J. L Koppel ◽  
John H Olwin

SummaryData have been presented on the in vitro effects of human chylomicra, low-density human plasma lipoproteins, and partially purified preparations of various phospholipids on human plasma euglobulin lysis. Euglobulin lysis was found to be accelerated by preparations of mixed soybean phospholipids (aso-lectin), cephalin, phosphatidyl inositol, phophatidyl serine and phosphatidyl ethanolamine. In contrast, it was found to be inhibited by preparations of human chylomicra, low-density human plasma liproproteins and lecithin. Inhibition of euglobulin lysis produced by any of these three agents could be diminished or completely overcome by the simultaneous presence of suitable levels of any one of the accelerating agents. In all cases studied, both inhibitory and accelerating effects were observed to be concentration-dependent. Evidence has been obtained to suggest that in the case of the accelerating agents the observed increased rate of euglobulin lysis is not a direct effect on lysis itself, but rather is due to more complete precipitation of plasminogen in the presence of these substances. On the other hand, it appears that the inhibitory effects observed are not related to the extent of plasminogen precipitation, but are actually true inhibitions of euglobulin lysis. The possible clinical significance of some of these observations has been briefly discussed.


1988 ◽  
Vol 66 (5) ◽  
pp. 442-448 ◽  
Author(s):  
Rafael Picorel ◽  
Gabriel Gingras

We have developed a simple and efficient method, using a mixed detergent system of sodium dodecyl sulfate and Triton X-100, for the preparative isolation of theB875 complex from Rhodobacter sphaeroides 2.4.1. As a bonus, the method allows the preparation of both the B875 and B800-850 complexes from the same batch of chromatophores. The preparations are spectrally pure, as indicated by absorption and circular dichroism spectroscopy. The latter method suggests that the Qy band of the B875 complex is due to weakly interacting bacteriochlorophyll molecules. Protein and pigment analysis shows that the B875 complex contains 2 mol of bacteriochlorophyll and 2 mol of sphaeroidene per mol of apoprotein (12 266 g), whereas the B800-850 complex contains 3 mol of bacteriochlorophyll and 1 mol of sphaeroidene per mol of apoprotein (11 497 g). While these stoichiometries are in accord with currently accepted models, they disagree with their published experimental basis. Phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl glycerol, and diphosphatidyl glycerol were found to be present in the B875 complex.


1978 ◽  
Vol 34 (1) ◽  
pp. 65-79
Author(s):  
R.S. Sohal ◽  
R.G. Bridges

A possible relationship between the phospholipid base composition of larvae of the housefly and the size, number and total volume of midgut mitochondria was examined. The phospholipid composition of the larvae was altered by restricting the amount of choline, substituting choline by N-dimethylethyl-(2-hydroxyethyl)-ammonium salt or 2-N-dimethylaminoethanol and by the addition of 2-aminobutan-1-ol to the larval diet. Mitochondrial measurements were made on electron micrographs of the epithelial cells in the midgut of third instar larvae. Reduction in the normal proportion of phosphatidylcholine in the phospholipids of the larvae was associated with an increase in the average size of the mitochondria and a decrease in their number, probably due to enhanced mitochondrial fusion. The opposite effect was noted when phosphatidyl-2-aminobutan-1-ol was present as a part replacement of the phosphatidyl-ethanolamine normally present in the larvae. Larvae which contained both phosphatidyl-2-aminobutan-1-ol as well as reduced amounts of phosphatidylcholine, contained mitochondria which were intermediate in both size and number. The effects associated with the changes in phosphatidylcholine and phosphatidyl-2-aminobutan-1-ol were independent of each other. The presence of the analogue of phosphatidylcholine and phosphatidyldimethylaminoethanol had no significant effect on the mitochondrial distribution. Total mitochondrial volume remained unaffected by alterations in the phospholipid composition of the larvae.


1992 ◽  
Vol 103 (3) ◽  
pp. 823-830 ◽  
Author(s):  
S.T. Furlong ◽  
K.S. Thibault ◽  
R.A. Rogers

Schistosomes do not make sterols or fatty acids de novo and thus require host lipids for survival. The acquisition of host lipids may also be an important factor in the schistosome's defense from host immunity; however, little is known about the regulation of this process. Here we have examined binding of radiolabeled and fluorescently labeled liposomes to schistosomula, and followed incorporation of fluorescent phospholipids into the worm by both morphological and biochemical methods. Saturable binding of radiolabeled phosphatidylcholine containing liposomes was observed and epifluorescence microscopy showed binding of C6-NBD-phosphatidylcholine (C6-NBD-PC), C12-NBD-phosphatidylcholine (C12-NBD-PC) and C6-NBD-phosphatidyl-ethanolamine (C6-NBD-PE) containing liposomes on the surface of the parasite. Following back-exchange with unlabeled liposomes, NBD-PC and NBD-PE were observed to be preferentially incorporated into specific cell types within the worm. Furthermore, cells which had accumulated the fluorescent lipid formed an interconnecting cellular network immediately below the tegument, identified as cytons. By contrast, fluorescein-PE was found only on the surface of the parasite and in the gut but not in the cytons. Biochemical analysis demonstrated that > 90% of the C6-NBD-PC and C12-NBD-PC remained as the intact molecule after a one hour incubation with the parasite, but that greater than 70% of the NBD-PE was converted to other lipids. These studies demonstrate that incorporation of phospholipid analogs into schistosomula can be followed morphologically and biochemically. As there was little localization of NBD-PE or NBD-PC in the gut, these analogs must be assimilated by crossing the tegument.(ABSTRACT TRUNCATED AT 250 WORDS)


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