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We showed DNA-binding activity of different classes of plasma lipoproteins in rats and humans. Experiments with fluorescent dye Hoechst 33258 showed that about 12% extracellular plasma DNA is present in circulating lipoproteins complexes; 7-8% of them with HDL. Structural HDL protein apoA-I probably plays the major role in the interaction between extracellular DNA and lipoprotein particle. Participation of lipoproteins in the transport of extracellular DNA can be considered as an important mechanism for elimination of nucleic acids from blood plasma.

Activities of matrix metalloproteinases 2 and 7 and α1-proteinase inhibitor were measured in patients with type 2 diabetes mellitus. Correlations between enzyme activity and the main parameters of carbohydrate metabolism were studied. In patients, significant reduction of matrix metalloproteinase activity in the serum was noted, which correlated with the decrease in blood concentration of C-peptide (r=0.8). At the same time, serum activity of α1-proteinase inhibitor increased. No significant relationships between patient's age, glucose concentration, fructosamine concentration, and matrix metalloproteinase activity were observed.

Experiments on cultured peritoneal macrophage from mice with HA-1 ascitic hepatoma showed that plasma lipoproteins present in the incubation medium decreased intracellular concentration of interleukin-1beta. These changes were most pronounced for high-density lipoproteins (alone or in combination with cortisol). Bacterial and yeast polysaccharides had little effect on interleukin-1beta concentration in macrophages. Addition of polysaccharides in combination with lipoproteins was followed by a 2-3-fold decrease in interleukin-1beta concentration. A combination of polysaccharides and high-density lipoproteins had the strongest effect. These properties of plasma lipoproteins should be taken into account in the correction of macrophage function during tumor growth.

Experiments on hepatocyte culture showed that apolipoprotein A-I—tetrahydrocortisol complex increases the rate of DNA, RNA, and protein biosynthesis measured by radioactive label incorporation. Apolipoprotein E acted as competitor of the apolipoprotein A-I—tetrahydrocortisol complex and abolished biological activity of the latter. We hypothesize that this mechanism of regulation plays an important role in processes of intracellular regeneration and proliferation.

The structure of lymphocyte and erythrocyte plasma membrane in patients with long persistence of tick-borne encephalitis virus was studied using fluorescent probes pyrene and 1-anilinonaphthalene-8-sulfonate. The authors analyze the clear-cut disorders in the membranes of both lymphocytes and erythrocytes in viral tick-borne-encephalitis from the viewpoint of generalized involvement of cell membranes in infectious process.

We studied the effects of lipopolysaccharide on activity of liver microsomal enzymes against the background of xenobiotics treatment. Against the background of lipopolysaccharide stimulation of macrophages we observed in vivo activation of cytochromes P-450 1A subfamily in liver microsomes with Arochlor 1254, but not induction of cytochrome P-450 2B subfamily with phenobarbital.

The interaction between recombinant soluble CD4 receptor (rsCD4) with human apolipoprotein A-I was studied by enzyme-linked immunosorbent assay. Our findings suggest that HIV-1 and human apolipoprotein A-I compete for the CD4 receptor and receptor for apoA-I.