title: The Mycobacterium tuberculosis recombinant LprN protein of mce4 operon induces Th-1 type response deleterious to protection in mice.
abstract: Lipoproteins are known to be effective immunogens and affect both innate and adaptive immunity. The lprN gene of Mycobacterium tuberculosis has been predicted to encode for a putative lipoprotein in silico. Here, we studied its function as an immunogen by in vivo studies in mice. The recombinant LprN protein, expressed and purified in Escherichia coli, triggered a cell-mediated immune response in BALB/c mice. This was observed by significantly higher T-cell proliferation and increased production of TNF-α and IFN-γ cytokines. However, pre-exposure to LprN protein failed to provide protection in mice after challenge with a virulent strain of M. tuberculosis. Histological examination showed an increase in tissue destruction in experimental animals, indicating an immunogenic potential for LprN protein that enhanced the virulence of bacilli.
authors.affiliation: Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
authors.forename: Rashmi
authors.initials: R
authors.lastname: Pasricha
authors.forename: Neeraj K
authors.initials: NK
authors.lastname: Saini
authors.forename: Nisha
authors.initials: N
authors.lastname: Rathor
authors.forename: Rakesh
authors.initials: R
authors.lastname: Pathak
authors.forename: Rajesh
authors.initials: R
authors.lastname: Sinha
authors.forename: Mandira
authors.initials: M
authors.lastname: Varma-Basil
authors.forename: Kiran
authors.initials: K
authors.lastname: Mishra
authors.forename: Vani
authors.initials: V
authors.lastname: Brahmachari
authors.forename: Mridula
authors.initials: M
authors.lastname: Bose
mesh_terms: D000818:Animals; D058491:Bacterial Load; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology*; D005260:Female; D005798:Genes, Bacterial; D054884:Host-Pathogen Interactions / Q000276:immunology; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000096:biosynthesis; D008168:Lung / Q000382:microbiology / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000276:immunology* / Q000472:pathogenicity; D009876:Operon; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D013154:Spleen / Q000382:microbiology / Q000473:pathology; D018417:Th1 Cells / Q000276:immunology*; D014397:Tuberculosis, Pulmonary / Q000276:immunology / Q000473:pathology / Q000517:prevention & control; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D014774:Virulence / Q000235:genetics / Q000276:immunology
chemical_list: D001426:Bacterial Proteins; C510664:Mce4A protein, Mycobacterium tuberculosis; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma
keywords: LprN; Mycobacterium tuberculosis; immunogen