title: Mycobacterium tuberculosis Rv1987 induces Th2 immune responses and enhances Mycobacterium smegmatis survival in mice.
abstract: Mycobacterium tuberculosis can interfere with host immune response and escape clearance through its specific antigens. M. tuberculosis Rv1987 encoded by region of difference (RD)-2 gene is a secretory protein with immunogenic potency. Here, we investigated the impact of Rv1987 on host cytokine responses and T cell polarization in mouse aerosol model. A recombinant M. smegmatis mc2155 strain that overexpressed Rv1987 protein (named MS1987) was constructed and used to infect C57BL/6 mice. The mc2155 harbored the empty vector (named MSVec) was as a control. The results showed that MS1987 challenged mice promoted Th2-biased cytokine responses with lower secretion of IFN-γ but higher production of IL-4 and Rv1987-specific IgG antibody compared to MSVec infected mice. Neutrophilic inflammation and high bacterial burden were observed in the lung tissues of MS1987 infected mice probably own to the failed Th1 cell immunity. Besides, subcutaneous injection of Rv1987 protein could mediate the Th1 cytokine responses caused by M. bovis BCG in mice. These results indicated that M. tuberculosis Rv1987 protein could modulate host immune response towards Th2 profile, which probably contributed to the immune evasion of bacteria from host elimination.
authors.affiliation: Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian 116044, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Sha
authors.affiliation: Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian 116044, China.
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Shi
authors.affiliation: Department of Microbiology, Dalian Medical University, Dalian 116044, China.
authors.forename: Guoying
authors.initials: G
authors.lastname: Deng
authors.affiliation: Department of Pathology, Dalian Medical University, Dalian 116044, China.
authors.forename: Lina
authors.initials: L
authors.lastname: Chen
authors.affiliation: Department of Biotechnology, Dalian Medical University, Dalian 116044, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xin
authors.affiliation: Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian 116044, China. Electronic address: yufang_ma@hotmail.com.
authors.forename: Yufang
authors.initials: Y
authors.lastname: Ma
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology* / Q000302:isolation & purification; D016207:Cytokines / Q000097:blood; D004195:Disease Models, Animal; D005260:Female; D007113:Immunity, Innate; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D007249:Inflammation / Q000276:immunology; D007371:Interferon-gamma / Q000096:biosynthesis / Q000276:immunology; D015847:Interleukin-4 / Q000096:biosynthesis / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL / Q000276:immunology / Q000382:microbiology; D009165:Mycobacterium Infections, Nontuberculous / Q000276:immunology / Q000382:microbiology*; D020102:Mycobacterium smegmatis / Q000166:cytology / Q000276:immunology*; D009169:Mycobacterium tuberculosis / Q000166:cytology / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology*; D014376:Tuberculosis / Q000276:immunology / Q000382:microbiology*
chemical_list: D000942:Antigens, Bacterial; D016207:Cytokines; C000611649:IFNG protein, mouse; D007074:Immunoglobulin G; D015847:Interleukin-4; D007371:Interferon-gamma
keywords: Immune evasion; Mycobacterium tuberculosis; Rv1987; Th2 immune response