Diacetylenic lipids in the design of stable lipopolymers able to complex and protect plasmid DNA

C. FACUNDO TEMPRANA, M. JIMENA PRIETO, DANIELA E. IGARTÚA, A. LIS FEMIA, M. SILVIA AMOR AND SILVIA DEL VALLE ALONSO

PLOS ONE

PUBLIC LIBRARY SCIENCE

Lugar: San Francisco; Año: 2017

1932-6203

Different viral and non-viralvectors have been designed to allow the delivery of nucleic acids in genetherapy. In general, non-viral vectors have been associated with increasedsafety for in vivo use; however,issues regarding their efficacy, toxicity and stability continue to drivefurther research. Thus, the aim of this study was to evaluate the potential useof the polymerizable diacetylenic lipid 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine(DC8,9PC) as a strategy to formulate stable cationic lipopolymers inthe delivery and protection of plasmid DNA. Cationic lipopolymers were preparedfollowing two different methodologies by using DC8,9PC,1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), and the cationic lipids(CL) 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP), stearylamine (SA), andmyristoylcholine chloride (MCL), in a molar ratio of 1:1:0.2 (DMPC:DC8,9PC:CL). The copolymerization methodologyallowed obtaining cationic lipopolymers which were smaller in size than thoseobtained by the cationic addition methodology although both techniquespresented high size stability over a 166-day incubation period at 4°C. Cationiclipopolymers containing DOTAP or MCL were more efficient in complexing DNA thanthose containing SA. Moreover, lipopolymers containing DOTAP were found to formhighly stable complexes with DNA, able to resist serum DNAses degradation.Furthermore, neither of the cationic lipopolymers (with or without DNA) inducedred blood cell hemolysis, although metabolic activity determined on the L-929and Vero cell lines was found to be dependent on the cell line, the formulationand the presence of DNA. The high stability and DNAprotection capacity as well as the reduced toxicity determined for the cationiclipopolymer containing DOTAP highlight the potential advantage of usinglipopolymers when designing novel non-viral carrier systems for use in in vivo gene therapy. Thus, this workrepresents the first steps toward developing a cationic lipopolymer-based genedelivery system using polymerizable and cationic lipids.