title: Evaluation of specific humoral immune response and cross reactivity against Mycobacterium tuberculosis antigens induced in mice immunized with liposomes composed of total lipids extracted from Mycobacterium smegmatis.
abstract: The development of a new tuberculosis (TB) vaccine has become one of the main objectives of the scientific community. Protein antigens have been widely explored as subunit TB vaccines, however lipid antigens could be equally important to be used or included in such a vaccine. The aim of this study was to demonstrate the potential of a liposome formulation composed of an extract of lipids from Mycobacterium smegmatis (Ms) as a TB vaccine candidate. We evaluated the immunogenicity of this formulation as well as the cross reactive response against antigens from Mycobacterium tuberculosis (MTb) in BALB/c mice. We determined the anti-liposome IgG response in sera from TB patients and from healthy subjects who displayed a positive (PPD+) or negative (PPD-) tuberculin skin test. A significant increase in anti-liposome IgG (p<0.05) was detected in animals immunized with Bacille Calmette-Guérin (BCG) compared with all groups, and in the group immunized with liposomes from Ms (LMs) compared to animals immunized with either LMs adjuvanted with aluminium (LMs-A) or the negative control group (phosphate buffered saline, PBS) respectively. With respect to the cross reactive response against a cocktail of cell wall antigens (CWA) from MTb, significantly higher IgG levels were observed in animals immunized with BCG and LMs compared to negative controls and either, aluminium-adjuvanted liposomes (LMs-A) or montanide (LMs-M) (p<0.05). Furthermore, the anti-liposome IgG response was significantly superior in sera from pulmonary TB patients compared to PPD+ and PPD- healthy subjects (p<0.001) suggesting the expression of these antigens in vivo during active MTb infection. The results obtained provide some evidence for the potential use of liposomes containing total lipid extracts of Ms as a TB vaccine candidate.
authors: Molecular Biology Department Finlay Institute, Ave. 27 No. 19805, La Lisa, La Havana, Cuba, AP. 16017, CP11600. mangeles@finlay.edu.cu
authors: María
authors: M
authors: de los Angeles García
authors: Reinier
authors: R
authors: Borrero
authors: Reynel
authors: R
authors: Marrón
authors: María E
authors: ME
authors: Lanio
authors: Lien
authors: L
authors: Canet
authors: Oscar
authors: O
authors: Otero
authors: Ramlah
authors: R
authors: Kadir
authors: Siti
authors: S
authors: Suraiya
authors: Caridad
authors: C
authors: Zayas
authors: Yamilé
authors: Y
authors: López
authors: Mohd
authors: M
authors: Nor Norazmi
authors: Maria E
authors: ME
authors: Sarmiento
authors: Armando
authors: A
authors: Acosta
mesh_terms: D000818:Animals; D002473:Cell Wall / Q000276:immunology; D003429:Cross Reactions; D005260:Female; D056724:Immunity, Humoral; D007074:Immunoglobulin G / Q000276:immunology; D008081:Liposomes / Q000008:administration & dosage / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009163:Mycobacterium bovis / Q000276:immunology; D020102:Mycobacterium smegmatis / Q000276:immunology*; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D014374:Tuberculin Test; D014376:Tuberculosis / Q000276:immunology / Q000517:prevention & control; D032581:Tuberculosis Vaccines / Q000276:immunology*; D014611:Vaccination
chemical_list: D007074:Immunoglobulin G; D008081:Liposomes; D032581:Tuberculosis Vaccines