title: Interactions of antitumour Sialyl Lewis X liposomes with vascular endothelial cells.
abstract: Recently, we showed that tetrasaccharide selectin ligand SiaLeX provided targeted delivery of liposomes loaded in the bilayer with melphalan lipophilic prodrug to tumour endothelium followed by severe injury of tumour vessels in a Lewis lung carcinoma model. Here, we study the impact of SiaLeX ligand on the interactions of liposomes with human umbilical vein endothelial cells (HUVEC) using flow cytometry, spectrofluorimetry and confocal microscopy. Liposomes composed of egg phosphatidylcholine/yeast phosphatidylinositol/1,2-dioleoyl glycerol ester of melphalan, 8:1:1, by mol, and varying percentages of lipophilic SiaLeX conjugate were labelled with BODIPY-phosphatidylcholine. The increase in SiaLeX content in liposomes led to a proportional increase in their uptake by cytokine-activated cells as opposed to non-activated HUVEC: for 10% SiaLeX liposomes, binding avidity and overall accumulation increased 14- and 6-fold, respectively. The early stages of intracellular traffic of targeted liposomes in the activated cells were monitored by co-localisation with the trackers of organelles. Endocytosis of SiaLeX liposomes occurred mostly via clathrin-independent pathways, which does not contradict the available literature data on E-selectin localisation in the plasma membrane. Using dual fluorescence labelling, with rhodamine-labelled phospholipid and calcein encapsulated at self-quenching concentrations, we found that SiaLeX liposomes undergo rapid (within minutes) internalisation by activated HUVEC accompanied by the disruption of liposomes; non-activated cells consumed a negligible dose of liposomes during at least 1.5h. Our data evidence the selective effect of SiaLeX formulations on activated endothelial cells and indicate their potential for intracellular delivery of melphalan lipophilic prodrug.
authors: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997 Moscow, Russian Federation.
authors: Anna
authors: A
authors: Alekseeva
authors: Gamaleya Research Institute of Epidemiology and Microbiology, Ministry of Health of Russian Federation, Gamalei 18, 123098 Moscow, Russian Federation.
authors: Marina
authors: M
authors: Kapkaeva
authors: Gamaleya Research Institute of Epidemiology and Microbiology, Ministry of Health of Russian Federation, Gamalei 18, 123098 Moscow, Russian Federation.
authors: Olga
authors: O
authors: Shcheglovitova
authors: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997 Moscow, Russian Federation.
authors: Ivan
authors: I
authors: Boldyrev
authors: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997 Moscow, Russian Federation.
authors: Galina
authors: G
authors: Pazynina
authors: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997 Moscow, Russian Federation.
authors: Nicolai
authors: N
authors: Bovin
authors: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997 Moscow, Russian Federation. Electronic address: elvod@lipids.ibch.ru.
authors: Elena
authors: E
authors: Vodovozova
mesh_terms: D018906:Antineoplastic Agents, Alkylating / Q000737:chemistry / Q000378:metabolism*; D002478:Cells, Cultured; D002626:Chemistry, Pharmaceutical; D004075:Diglycerides / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D004337:Drug Carriers; D019040:E-Selectin / Q000378:metabolism; D004705:Endocytosis / Q000187:drug effects; D005434:Flow Cytometry; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D016256:Lewis X Antigen / Q000737:chemistry / Q000378:metabolism*; D008055:Lipids / Q000737:chemistry*; D008081:Liposomes; D008558:Melphalan / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism*; D018613:Microscopy, Confocal; D010713:Phosphatidylcholines / Q000737:chemistry; D010716:Phosphatidylinositols / Q000737:chemistry; D000080506:Sialyl Lewis X Antigen; D013050:Spectrometry, Fluorescence; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D018906:Antineoplastic Agents, Alkylating; D004075:Diglycerides; D004337:Drug Carriers; D019040:E-Selectin; D016256:Lewis X Antigen; D008055:Lipids; D008081:Liposomes; D010713:Phosphatidylcholines; D010716:Phosphatidylinositols; C546936:SELE protein, human; D000080506:Sialyl Lewis X Antigen; D014409:Tumor Necrosis Factor-alpha; D008558:Melphalan; C013965:diolein
keywords: Drug targeting; E-selectin; Endocytosis; Melphalan lipophilic prodrug; Nanosized liposomes; Sialyl Lewis X