Email updates

Keep up to date with the latest news and content from BMC Immunology and BioMed Central.

Open Access Highly Accessed Research article

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

Rogério S Rosada1, Lucimara Gaziola de la Torre2, Fabiani G Frantz13, Ana PF Trombone1, Carlos R Zárate-Bladés1, Denise M Fonseca1, Patrícia RM Souza1, Izaíra T Brandão1, Ana P Masson1, Édson G Soares4, Simone G Ramos4, Lúcia H Faccioli3, Célio L Silva1, Maria HA Santana2 and Arlete AM Coelho-Castelo1*

Author Affiliations

1 Núcleo de Pesquisas em Tuberculose, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil

2 Departamento de Processos Biotecnológicos, Faculdade de Engenharia Química, Universidade Estadual de Campinas, São Paulo, Brazil

3 Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil

4 Departamento de Patologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil

For all author emails, please log on.

BMC Immunology 2008, 9:38  doi:10.1186/1471-2172-9-38

Published: 22 July 2008

Abstract

Background

The greatest challenges in vaccine development include optimization of DNA vaccines for use in humans, creation of effective single-dose vaccines, development of delivery systems that do not involve live viruses, and the identification of effective new adjuvants. Herein, we describe a novel, simple technique for efficiently vaccinating mice against tuberculosis (TB). Our technique consists of a single-dose, genetic vaccine formulation of DNA-hsp65 complexed with cationic liposomes and administered intranasally.

Results

We developed a novel and non-toxic formulation of cationic liposomes, in which the DNA-hsp65 vaccine was entrapped (ENTR-hsp65) or complexed (COMP-hsp65), and used to immunize mice by intramuscular or intranasal routes. Although both liposome formulations induced a typical Th1 pattern of immune response, the intramuscular route of delivery did not reduce the number of bacilli. However, a single intranasal immunization with COMP-hsp65, carrying as few as 25 μg of plasmid DNA, leads to a remarkable reduction of the amount of bacilli in lungs. These effects were accompanied by increasing levels of IFN-γ and lung parenchyma preservation, results similar to those found in mice vaccinated intramuscularly four times with naked DNA-hsp65 (total of 400 μg).

Conclusion

Our objective was to overcome the significant obstacles currently facing DNA vaccine development. Our results in the mouse TB model showed that a single intranasal dose of COMP-hsp65 elicited a cellular immune response that was as strong as that induced by four intramuscular doses of naked-DNA. This formulation allowed a 16-fold reduction in the amount of DNA administered. Moreover, we demonstrated that this vaccine is safe, biocompatible, stable, and easily manufactured at a low cost. We believe that this strategy can be applied to human vaccines to TB in a single dose or in prime-boost protocols, leading to a tremendous impact on the control of this infectious disease.