title: Mycobacterium tuberculosis Rv1419 encodes a secreted 13 kDa lectin with immunological reactivity during human tuberculosis.
abstract: In this study, we have identified a secreted 13 kDa lectin from Mtb (Mtb, Mycobacterium tuberculosis; sMTL-13) by homology search of a non-redundant lectin database. Bioinformatic analysis revealed that sMTL-13 belongs to the ricin-type beta-trefoil family of proteins containing a Sec-type signal peptide present in Mtb complex species, but not in non-tuberculous mycobacteria. Following heterologous expression of sMTL-13 and generation of an mAb (clone 276.B7/IgG1kappa), we confirmed that this lectin is present in culture filtrate proteins from Mtb H37Rv, but not in non-tuberculous mycobacteria-derived culture filtrate proteins. In addition, sMTL-13 leads to an increased IFN-gamma production by PBMC from active tuberculosis (ATB) patients. Furthermore, sera from ATB patients displayed high titers of IgG Ab against sMTL-13, a response found to be decreased following successful anti-tuberculosis therapy. Together, our findings reveal a secreted 13 kDa ricin-like lectin from Mtb, which is immunologically recognized during ATB and could serve as a biomarker of disease treatment.
authors.affiliation: Laboratório de Imunologia e Doenças Infecciosas, Departamento de Microbiologia e Parasitologia, Universidade Federal de Santa Catarina-SC, Brazil.
authors.forename: Lucas
authors.initials: L
authors.lastname: Nogueira
authors.forename: Fernanda C
authors.initials: FC
authors.lastname: Cardoso
authors.forename: Ana M
authors.initials: AM
authors.lastname: Mattos
authors.forename: Juliano
authors.initials: J
authors.lastname: Bordignon
authors.forename: Cláudia P
authors.initials: CP
authors.lastname: Figueiredo
authors.forename: Pedro
authors.initials: P
authors.lastname: Dahlstrom
authors.forename: Cristiane C
authors.initials: CC
authors.lastname: Frota
authors.forename: Cláudia N
authors.initials: CN
authors.lastname: Duarte Dos Santos
authors.forename: Marcelo
authors.initials: M
authors.lastname: Chalhoub
authors.forename: Benildo S
authors.initials: BS
authors.lastname: Cavada
authors.forename: Henrique C
authors.initials: HC
authors.lastname: Teixeira
authors.forename: Sérgio C
authors.initials: SC
authors.lastname: Oliveira
authors.forename: Manoel
authors.initials: M
authors.lastname: Barral-Netto
authors.forename: André
authors.initials: A
authors.lastname: Báfica
mesh_terms: D000595:Amino Acid Sequence; D000907:Antibodies, Bacterial / Q000235:genetics / Q000276:immunology; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D001483:Base Sequence; D015153:Blotting, Western; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D007150:Immunohistochemistry; D037102:Lectins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D008969:Molecular Sequence Data; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D014397:Tuberculosis, Pulmonary / Q000235:genetics / Q000276:immunology* / Q000378:metabolism
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D007074:Immunoglobulin G; D037102:Lectins