ИСТИНА

The most accessible methods of drug administration - oral administration and intravenous injection - lead to systemic distribution of the drug throughout the body, which is accompanied by a number of problems. Drug molecules can interact with metabolic enzymes. It is difficult to maintain the concentration of the drug at a therapeutic level. Distribution into healthy tissues leads to side effects. These problems can be solved using the targeted delivery approach. The localization of the drug in tissues and organs in need of therapy reduce side effects in other parts of the body. The targeted delivery platform is constructed using chemical design of bionanomaterials. When evaluating the effectiveness of a targeting molecule, surface plasmon resonance spectroscopy is actively used to determine the equilibrium dissociation constant of the ligand-receptor complex. The delivery of biologically active molecules of various nature was studied in this work. The targeted delivery systems were characterized and their targeting efficiencies were examined. Variety of low molecular weight compounds was applied to liver-targeted delivery: docetaxel (a well-known cytostatic drug for the treatment of hepatocellular carcinoma), betulin (a triterpenoid exhibiting cytostatic properties, a potentially new drug for the treatment of HCC), atorvastatin (an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, used to lower cholesterol levels in patients with hypercholesterolemia). The mechanism of receptor-mediated endocytosis involving the asialoglycoprotein receptor (ASGPR) was employed. Natural native ASGPR ligand N-acetylgalactosamine (GalNAc) was used as the targeting moiety. GalNAc-aimed conjugates with different lengths of the linker were obtained and characterized, as well as triantennary ligand conjugates with three GalNAc residues. The affinity of the conjugate to ASGPR was estimated using both molecular dynamics and surface plasmon resonance spectroscopy. The safety of the conjugates was examined by measuring their cytotoxicity in different cellular models (ASGPR (+) cell lines HepG2 and Huh-7, as well as ASGPR (-) lines PC-3 and Hek-293). The targeted delivery of macromolecular compounds was studied aiming on other lectin-type receptors: macrophage mannose receptor (CD206) and E-selectin (CD62E). Targeted delivery of cationic polymer-based polyplexes was employed for handling nucleic acid molecules. Cationic diblock copolymers of polyethylene glycol (PEG) and poly-L-lysine (PLL) or poly{N-[N-(2-aminoethyl)-2-aminoethyl]aspartamide} (pAsp(DET)) are synthesized and used to form polyplexes with a plasmid DNA (pDNA) that are decorated with mannose moieties, serving as the targeting ligands for the C type lectin receptors displayed at the surface of macrophages. Nanocomplexes of different charge ratios and different degrees of crosslinking were synthesized and characterized. Successful delivery of the nucleic acid into the cell was demonstrated. The cross-linking of the polyplexes decrease both the toxicity and the transfection enhancement as well. The biocompatible mannose modified non-cross-linked pDNA-contained polyplexes based on PEG-pAsp(DET) copolymers exhibit ca. 500-times greater transfection activity in IC-21 macrophages compared to the mannose-free polyplexes. The results suggest that designed targeted delivery platform can be used for further development of systems for targeted delivery. This work was supported in part by the Russian Science Foundation grants 20-63-46029, 20-64-46029, State Topic АААА-А21-121011290089-4 and MSU Program of Development.