title: TLR2-targeted secreted proteins from Mycobacterium tuberculosis are protective as powdered pulmonary vaccines.
abstract: Despite considerable research efforts towards effective treatments, tuberculosis (TB) remains a staggering burden on global health. Suitably formulated sub-unit vaccines offer potential as safe and effective generators of protective immunity. The Mycobacterium tuberculosis antigens, cutinase-like proteins (Culp) 1 and 6 and MPT83, were conjugated directly to the novel adjuvant Lipokel (Lipotek Pty Ltd), a TLR2 ligand that delivers antigen to immune cells in a self-adjuvanting context. Protein-Lipokel complexes were formulated as dry powders for pulmonary delivery directly to the lungs of mice by intra-tracheal insufflation, leading to recruitment of neutrophils and antigen presenting cell populations to the lungs at 72 h, that persisted at 7 days post immunisation. Significant increases in the frequency of activated dendritic cells were observed in the mediastinal lymph node (MLN) at 1 and 4 weeks after homologous boosting with protein-Lipokel vaccine. This was associated with the increased recruitment of effector CD4(+) and CD8(+) T-lymphocytes to the MLN and systemic antigen-specific, IFN-γ producing T-lymphocyte and IgG responses. Notably, pulmonary immunisation with either Culp1-6-Lipokel or MPT83-Lipokel powder vaccines generated protective responses in the lungs against aerosol M. tuberculosis challenge. The successful combination of TLR2-targeting and dry powder vaccine formulation, together with important practical benefits, offers potential for pulmonary vaccination against M. tuberculosis.
authors.affiliation: Tuberculosis Research Program, Centenary Institute, Locked Bag No 6, Newtown, NSW 2042, Australia.
authors.forename: Anneliese S
authors.initials: AS
authors.lastname: Tyne
authors.forename: John Gar Yan
authors.initials: JG
authors.lastname: Chan
authors.forename: Erin R
authors.initials: ER
authors.lastname: Shanahan
authors.forename: Ines
authors.initials: I
authors.lastname: Atmosukarto
authors.forename: Hak-Kim
authors.initials: HK
authors.lastname: Chan
authors.forename: Warwick J
authors.initials: WJ
authors.lastname: Britton
authors.forename: Nicholas P
authors.initials: NP
authors.lastname: West
mesh_terms: D000276:Adjuvants, Immunologic / Q000378:metabolism; D000281:Administration, Intranasal; D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002265:Carboxylic Ester Hydrolases / Q000235:genetics / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology; D005260:Female; D007074:Immunoglobulin G / Q000276:immunology; D007371:Interferon-gamma / Q000096:biosynthesis; D008198:Lymph Nodes / Q000276:immunology; D008565:Membrane Proteins / Q000235:genetics / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000276:immunology*; D011208:Powders / Q000008:administration & dosage; D051195:Toll-Like Receptor 2 / Q000276:immunology* / Q000378:metabolism; D014376:Tuberculosis / Q000276:immunology / Q000517:prevention & control*; D032581:Tuberculosis Vaccines / Q000276:immunology*; D014611:Vaccination / Q000379:methods; D014614:Vaccines, Synthetic / Q000276:immunology*
chemical_list: D000276:Adjuvants, Immunologic; D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D007074:Immunoglobulin G; C094904:MPB83 protein, Mycobacterium; D008565:Membrane Proteins; D011208:Powders; D051195:Toll-Like Receptor 2; D032581:Tuberculosis Vaccines; D014614:Vaccines, Synthetic; C072681:Mycobacterium tuberculosis antigens; D007371:Interferon-gamma; D002265:Carboxylic Ester Hydrolases; C019952:cutinase
keywords: Cutinase-like protein1-6; Lipokel; MPT83; Powdered pulmonary vaccine; TLR-2; Tuberculosis