Cationic Solid Lipid Nanoparticles Loaded by Cystein Proteinase Genes as a Novel anti-Leishmaniasis DNA Vaccine Delivery System: Characterization and in vitro Evaluations

Abstract

-Purpose. Leishmaniasis is a major health problem in many tropical and sub-tropical countries and development of a safe and easily-available vaccine has high priority. Although several antigens potentially capable of inducing protective immunity have been studied, in the absence of pharmaceutical industry interest they have remained as fine publications only. Amongst them, Cathepsin L-like cysteine proteinases (CPs) have received considerable attention and type I and II CPs have been used in a heterologous prime-boost vaccination regime for experimental visceral leishmaniasis in dogs. Due to the promising results of the mentioned vaccination regime, we aimed to evaluate cationic solid lipid nanoparticles (cSLNs) for in vitro delivery of cpa, cpb and cpb CTE intended to be used as a cocktail DNA vaccine in our forthcoming studies. Methods: cSLNs were formulated of cetyl palmitate, cholesterol, DOTAP and Tween 80 via melt emulsification method followed by high shear homogenization. Different formulations were prepared by anchoring pDNAs on the surface of cSLNs via charge interaction. The formulations were characterized according to their size and zeta potential as well as pDNA integrity and stability against DNase I treatment. Lipoplexes' cytotoxicity was investigated on COS-7 cells by MTT test. The effect of the DOTAP:pDNA ratio on protection ability and cytotoxicity was also studied. In vitro transfection efficiency was qualified by florescent microscopy and quantified using flow cytometry technique. Results: cSLN-pDNA complexes were formulated with suitable size and zeta potential. Efficiency/cytotoxicity ratio of cSLN-pDNAs formulations was comparable to linear PEI-25kDa-pDNAs polyplexes while exhibiting significantly lower cytotoxicity. Conclusion: Tested formulations were able to deliver immunogenic CP genes efficiently. This data proves the ability of this system as a promising DNA vaccine carrier for leishmaniasis to cover the main drawback of naked pDNA delivery that is rapidly elimination from the circulation.

Effects of Base Polymer Hydrophobicity and End-Group Modification on Polymeric Gene Delivery

“…PEI complexes were reported to yield 29.14% transfection and optimized solid lipid nanoparticles were reported to result in 14.64% transfection with reduced cytotoxicity as compared to PEI. 33 Electroporation has been reported to yield 71.23% transfection. 34 …”

Successfully Improving Ocular Drug Delivery Using the Cationic Nanoemulsion, Novasorb

“…DOPE, which also harbors a negative charge, is a neutral “helper” lipid often included in cationic lipid formulations like cationic nanoemulsions [40]. Cationic solid lipid nanoparticles were successfully made with DOTAP to transport DNA vaccines [41]. Hagigit and colleagues [42, 43] showed that using DOTAP was better than the seminatural lipid oleylamine to make stable cationic emulsions.…”

Drug Resistance in Leishmaniasis: Current Drug-Delivery Systems and Future Perspectives

“…Nanotechnology presents an extraordinary opportunity in rational delivery of drugs to the infection site following systemic administration. Examples of nanotechnology progress in pharmaceutical product include liposomes [20], niosomes [72], nanodisks [73], emulsions [74], solid lipid nanoparticles [75], polymeric nanoparticles [76] and polymeric drug conjugates (FiguRe 2) [77,78]. Therefore, current status of nanotechnology-based Drug resistance in leishmaniasis: current drug-delivery systems & future perspectives | Review www.future-science.com colloidal drug-delivery systems and the advances in the evaluation and development of novel drugdelivery systems against leishmaniasis shall be addressed in detail in the following sections.…”

“…Mehnert demonstrated a detailed overview about the different ways of solid-lipid nanoparticles production and applications [103]. Recently, solid-lipid nanoparticles loaded by cysteine proteinase genes showed a promising DNA vaccine-delivery system for leishmaniasis [75].…”