[Macrophage activation by blastolysin]. / Aktivatsiia makrofagov blastolizinom.

Blastolysin consisting largely of glycopeptide fragments of cell walls from Lactobacillus bulgaricus has a significant antineoplastic activity against a number of transplanted and spontaneous animal tumours. Blastolysin exerts a pronounced adjuvant action and activates the cells of the mononuclear phagocytic system. This is shown by stimulation of phagocytosis and digestion as well as by acquired ability of macrophages to elicit a cytotoxic action on allogeneic and syngeneic target cells (labelled with radioactive chromium) with abnormal growth. Administration of blastolysin or BCG was demonstrated to lead to variations in the time course of macrophage acquired cytotoxicity. Macrophage activation induced by blastolysin has a clearly pronounced two-phasic nature. During the first short phase the cytotoxicity is seen 2 hours following blastolysin administration, rapidly disappears and emerges after 2 weeks, remaining unchanged up to the 5th week (experimental period).

[Investigation of lipid-exchange lipoproteins from rat liver and hepatoma 27]. / Issledovanie lipidperenosiashchikh lipoproteinov gepatomy 27 i pecheni krys.

A phospholipid exchange lipoprotein from the postmicrosomal supernatant of rat hepatoma 27, which stimulated in vitro the exchange of sphingomyelin between mitochondria and microsomes, was found. Sphingomyelin is incorporated into the mitochondria under incubation of this complex with rat liver mitochondria (in which sphingomyelin is absent) an microsomes. Under the same conditions the phospholipid exchange lipoproteins of rat liver do not transfer sphingomyelin form microsomes to mitochrondria.

[Fatty acid composition and unsaturated of intracellular membrane phospholipids from rat liver and hepatoma 27]. / Zhirnokislotnyi sostav i nenasyshchennost' fosfolipidov vnutrikletochnykh membran gepatomy-27 i pechehi krys

The fatty acid composition of phospholipids of mitochondria and microsomes from rat liver and hepatoma 27 was investigated. Basing on the fatty acid and phospholipid composition the unsaturation of the lipid bilayer of the intracellular membranes was calculated. The unsaturation of the phospholipids of the hepatoma mitochondria and microsomes was found to be much lower than that of the corresponding rat liver membranes. The lipid bilayer of the rat liver and hepatoma plasma membranes was shown to be more saturated than that of the intracellular membranes.

[Phospholipid exchange between mitochondria and microsomes of rat hepatoma 27]. / Obmen fosfolipidami mezhdu mitokhondriiami i mikrosomami gepatomy 27 krys

The phospholipid exchange in vitro between mitochondria and microsomes from rat liver and rat hepatoma 27 was investigated. On incubation with a postmicrosomal protein fraction the phospholipid exchange between subcellular fractions of the tumor was found to proceed much faster and less specific than between mitochondria and microsomes from normal liver. These results indicate that the earlier demonstrated lipid dedifferentiation of tumor cell membranes may be connected with an altered transmembrane phospholipid exchange in vivo.

[The relationship between cholesterol, shpingomyelin and phosphatidyl choline in liver and hepatoma cell membranes]. / Sootnosheniia kholesterina, sfingomielina i fosfatidilkholina v kletochnykh membranakh gepatomy i pecheni

The cholesterol, sphingomyelin and phosphatidylcholine content in different cell membranes of liver and hepatoma was studied. Significant amounts of cholesterol were found in all the subcellular fractions of hepatoma, whereas in the liver cholesterol is localized mainly in the plasma membranes. A direct relation between the content of cholesterol and sphingomyelin was demonstrated. Possible effects of the cholesterol : : sphingomyelin : phosphatidylcholine ratio on the properties of cell membranes are discussed.