Cationic liposomes produced via ethanol injection method for dendritic cell therapy

<p>Cationic liposomes can be designed and developed in order to be an efficient gene delivery system for mammalian cells. Dendritic cell (DC) vaccines can be used to treat cancer, as cationic liposomes can deliver tumor antigens to cells while cells remain active. However, most methods used for liposome production are not able to reproduce in large scale the physicochemical and biological properties of liposomes produced in laboratory scale. In this context, ethanol injection method achieved promising results, although requiring post-treatment for size reduction and/or to remove residual ethanol. Thus, the purpose of this study was to generate cationic liposomes suitable for gene therapies via ethanol injection method in only one step (VEI) and compared to those submitted to a size reduction processes by microfluidization (MFV). For this, the method to produce cationic liposomes composed of egg phosphatidylcholine (EPC), 1,2-dioleoyl-3-trimethylammonium propane (DOTAP) and 1,2-dioleoylphosphatidylethanolamine (DOPE) was optimized using a statistical design approach. As a result, the size of VEI decreased from 290 nm to 110 nm and the polydispersity from 0.54 to 0.17. In the case of MFV, size decreased from 128 nm to 107 nm and polydispersity from 0.40 to 0.18. ST and MFV before and after optimization were also characterized in terms of morphology by transmission electron microscopy (TEM) and structure by differential scanning calorimetry (DSC). Finally, to show their potential in gene/immune therapies applications, DCs were stimulated by such liposomes. Cells internalized liposomes, increasing expression of the costimulatory molecule CD86 and inducing T lymphocyte proliferation.</p

Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes-4

At received four intramuscular doses of naked DNA (400 μg), BCG or saline. Thirty days after the last dose, mice were challenged intra-tracheally with H37RV and 30 days post infection we performed histological analysis of the lung. (A) non-infected; (B) saline; (C) naked hsp65; (D) COMP-hsp65 and (E) BCG groups. Representative sections of HE staining. Magnifications: ×65.<p><b>Copyright information:</b></p><p>Taken from "Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes"</p><p>http://www.biomedcentral.com/1471-2172/9/38</p><p>BMC Immunology 2008;9():38-38.</p><p>Published online 22 Jul 2008</p><p>PMCID:PMC2500095.</p><p></p

Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes-7

(cationic lipid:DNA); E and F represent liposomes complexing DNA at the same molar charge ratio. Bars indicate: A, C, E – 1000 nm; B, D, F – 200 nm.<p><b>Copyright information:</b></p><p>Taken from "Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes"</p><p>http://www.biomedcentral.com/1471-2172/9/38</p><p>BMC Immunology 2008;9():38-38.</p><p>Published online 22 Jul 2008</p><p>PMCID:PMC2500095.</p><p></p

Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes-2

Osome (corresponding to 50 μg of DNA). Anti-hsp65 antibody levels were evaluated in mice serum by ELISA 30 days after the last immunization. ) IgG2a and ) IgG1 isotypes. Results are presented by mean ± SD of optical density. *p < 0.05 were considered significant when compared to saline group or their respective controls.<p><b>Copyright information:</b></p><p>Taken from "Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes"</p><p>http://www.biomedcentral.com/1471-2172/9/38</p><p>BMC Immunology 2008;9():38-38.</p><p>Published online 22 Jul 2008</p><p>PMCID:PMC2500095.</p><p></p

Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes-3

A 15-day interval, b) a single dose of liposomes (25 μg) by intranasal instillation, c) four doses of naked DNA (100 μg each) by intramuscular route at a 15-day interval or d) one dose of BCG (Moreau strain) given by subcutaneous injection of about 10live bacteria in 100 μl saline. Thirty days after the last dose, mice were challenged intra-tracheally with H37RV and 30 days post infection we performed CFU analysis. Data represent the mean logCFU counts ± SD of six mice per group of one of three independent experiments. *p < 0.01 were considered significant when compared to the saline group.<p><b>Copyright information:</b></p><p>Taken from "Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes"</p><p>http://www.biomedcentral.com/1471-2172/9/38</p><p>BMC Immunology 2008;9():38-38.</p><p>Published online 22 Jul 2008</p><p>PMCID:PMC2500095.</p><p></p

Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes-0

(cationic lipid:DNA); E and F represent liposomes complexing DNA at the same molar charge ratio. Bars indicate: A, C, E – 1000 nm; B, D, F – 200 nm.<p><b>Copyright information:</b></p><p>Taken from "Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes"</p><p>http://www.biomedcentral.com/1471-2172/9/38</p><p>BMC Immunology 2008;9():38-38.</p><p>Published online 22 Jul 2008</p><p>PMCID:PMC2500095.</p><p></p

Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes-5

inflammation ± SD of six mice per group of one of three independent experiments. *p < 0.01 were considered significant when compared to the saline group.<p><b>Copyright information:</b></p><p>Taken from "Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes"</p><p>http://www.biomedcentral.com/1471-2172/9/38</p><p>BMC Immunology 2008;9():38-38.</p><p>Published online 22 Jul 2008</p><p>PMCID:PMC2500095.</p><p></p

Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes-6

Dose of 25 μg). Thirty days after the last dose, mice were challenged intra-tracheally with H37RV and 30 days post infection, IFN-γ (), IL-12 () and IL-10 () levels were determined by ELISA in lung homogenate. Data represent the mean ± SD of six mice per group of one of three independent experiments. *p < 0.01 were considered significant when compared to the saline group.<p><b>Copyright information:</b></p><p>Taken from "Protection against tuberculosis by a single intranasal administration of DNA-hsp65 vaccine complexed with cationic liposomes"</p><p>http://www.biomedcentral.com/1471-2172/9/38</p><p>BMC Immunology 2008;9():38-38.</p><p>Published online 22 Jul 2008</p><p>PMCID:PMC2500095.</p><p></p