Biophysical Society Thematic Meeting | Ascona, Switzerland

Liposomes, Exosomes, and Virosomes: From Modeling Complex Membrane Processes to Medical Diagnostics and Drug Delivery

Poster Abstracts

36-POS Board 18 Newly Synthesized Liposomal Antituberculotic Compounds and Effects on In Vitro Model Systems Nikoletta Kósa 1 , Kata Horváti 2 , Barnabás Bocskei-Antal 1 , Szilvia Bosze 2 , Levente Herényi 1 , István Voszka 1 . 2 MTA− ELTE, Budapest, Hungary. 1 Semmelweis University, Budapest, Hungary, Introduction . Liposomes are widely investigated nanocarriers, which are capable for incorporation of both lipid-soluble and water-soluble drugs. WHO aimed to eradicate TB disease, which is caused by Mycobacterium tuberculosis bacteria. Aim. Preparation and encapsulation of newly synthesized antituberculotic compound into liposomes. To enhance the encapsulation efficiency and to target intracellular bacteria in the macrophages. Methods .We have prepared two types of liposomes. Type I. consists of dipalmitoyl phosphatidylcholine (DPPC). Type II. consists of: dioleoylphosphatidylethanolamine (DOPE), cholesteryl hemisuccinate (CHEMS) and pegylated distearoyl phosphatidylethanolamine (DSPE-PEG). We used thin lipid film technology to prepare multilamellar vesicles (MLV) and henceforward both types were treated with extrusion technique to get small unilamellar vesicles (SUV). The size distribution of liposomes was determined/measured with dynamic light scattering (DLS). The change of diameter of vesicles shows the rate of aggregation. The used antituberculotic compounds were: TB 501, TB 504, TB 505 and TB 515 (chemical structure not published yet). Encapsulation efficiency was determined by measuring absorbance after size exclusion chromatography (SEC). Cellular uptake of liposomal compounds and non-encapsulated drugs was measured by flow cytometry on MonoMac6 human monocytic cell line. Intracellular fluorescence intensity and forward-scattered light (FSC) of MonoMac6 cells was monitored (488 nm (Coherent Sapphire, 22 mW) laser, which is proportional to the cellular uptake. Results. The extrusion method resulted rather uniform and stable vesicles. Encapsulation efficiency was influenced by the physico-chemical properties of antituberculotic compounds. The in vitro activity of liposomal antituberculotic compounds was determined on M. tuberculosis H37Rv culture. Considering that M. tuberculosis is an intracellular pathogen the effect of the compounds was studied on M. tuberculosis H37Rv infected MonoMac6 human monocytes. This work was supported by Hungarian Research Fund 104275.

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