Fusion protein Ag85B-MPT64(190-198)-Mtb8.4 has higher immunogenicity than Ag85B with capacity to boost BCG-primed immunity against Mycobacterium tuberculosis in mice.
Tuberculosis (TB) remains a major infectious disease worldwide despite chemotherapy and BCG vaccine. The efficacy of the current TB vaccine BCG varies from 0 to 80%. New vaccines that have better protection than BCG or have the capability to boost BCG-primed immunity are urgently needed. We have previously constructed a fusion protein Ag85B-MPT64(190-198)-Mtb8.4 (AMM). In this study, we investigated the immunogenicity of the fusion protein AMM in a novel adjuvant of dimethyl-dioctyldecyl ammonium bromide and BCG polysaccharide nucleic acid (DDA-BCG PSN), and its capacity to boost BCG-primed immunity. The anti-Ag85B antibodies IgG1 and IgG2a were determined using ELISA and the number of spleen cells secreting IFN-gamma was determined by ELISPOT. In addition, the ability of the subunit vaccine AMM to boost BCG-primed immunity against Mycobacterium tuberculosis was analyzed. The fusion protein AMM induced more effective humoral and cell-mediated immune responses in mice than Ag85B alone. Mice primed with BCG vaccination followed by boosting with AMM produced a stronger immune response and afforded a better protection against M. tuberculosis infection than mice immunized with BCG alone or BCG priming followed by boosting with Ag85B. These findings suggest that AMM is a promising candidate subunit vaccine to enhance the protective efficiency of BCG.
Luo
Yu
Y
Lanzhou Center for Tuberculosis Research & Institute of Pathogenic Biology, School of Basic Medical Sciences, Lanzhou University, China.
Wang
Bingxiang
B
Hu
Lina
L
Yu
Hongjuan
H
Da
Zejiao
Z
Jiang
Wenwen
W
Song
Nannan
N
Qie
Yaqing
Y
Wang
Honghai
H
Tang
Zhijiao
Z
Xian
Qiaoyang
Q
Zhang
Ying
Y
Zhu
Bingdong
B
D000217:Acyltransferases / Q000276:immunology*; D000276:Adjuvants, Immunologic; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000276:immunology*; D001500:BCG Vaccine / Q000276:immunology*; D001426:Bacterial Proteins / Q000276:immunology*; D005260:Female; D007111:Immunity, Cellular; D056724:Immunity, Humoral; D007074:Immunoglobulin G / Q000097:blood; D007371:Interferon-gamma; D051379:Mice; D008810:Mice, Inbred C57BL; D009169:Mycobacterium tuberculosis / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000276:immunology*; D014376:Tuberculosis / Q000276:immunology / Q000517:prevention & control*; D022223:Vaccines, Subunit / Q000276:immunology
D000276:Adjuvants, Immunologic; D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001500:BCG Vaccine; D001426:Bacterial Proteins; D007074:Immunoglobulin G; D011993:Recombinant Fusion Proteins; D022223:Vaccines, Subunit; D007371:Interferon-gamma; D000217:Acyltransferases; C121433:antigen 85B, Mycobacterium tuberculosis