title: Expression of cathelicidin LL-37 during Mycobacterium tuberculosis infection in human alveolar macrophages, monocytes, neutrophils, and epithelial cells.
abstract: The innate immune response in human tuberculosis is not completely understood. To improve our knowledge regarding the role of cathelicidin hCAP-18/LL37 in the innate immune response to tuberculosis infection, we used immunohistochemistry, immunoelectron microscopy, and gene expression to study the induction and production of the antimicrobial peptide in A549 epithelial cells, alveolar macrophages (AM), neutrophils, and monocyte-derived macrophages (MDM) after infection with Mycobacterium tuberculosis. We demonstrated that mycobacterial infection induced the expression and production of LL-37 in all cells studied, with AM being the most efficient. We did not detect peptide expression in tuberculous granulomas, suggesting that LL-37 participates only during early infection. Through the study of Toll-like receptors (TLR) in MDM, we showed that LL-37 can be induced by stimulation through TLR-2, TLR-4, and TLR-9. This last TLR was strongly stimulated by M. tuberculosis DNA. We concluded that LL-37 may have an important role in the innate immune response against M. tuberculosis.
authors.affiliation: Unidad de Investigación Médica-Zacatecas, IMSS, Zacatecas, México.
authors.forename: Bruno
authors.initials: B
authors.lastname: Rivas-Santiago
authors.forename: Rogelio
authors.initials: R
authors.lastname: Hernandez-Pando
authors.forename: Claudia
authors.initials: C
authors.lastname: Carranza
authors.forename: Esmeralda
authors.initials: E
authors.lastname: Juarez
authors.forename: Juan Leon
authors.initials: JL
authors.lastname: Contreras
authors.forename: Diana
authors.initials: D
authors.lastname: Aguilar-Leon
authors.forename: Martha
authors.initials: M
authors.lastname: Torres
authors.forename: Eduardo
authors.initials: E
authors.lastname: Sada
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000096:biosynthesis*; D018893:Bronchoalveolar Lavage; D002460:Cell Line; D002478:Cells, Cultured; D003593:Cytoplasm / Q000737:chemistry; D004847:Epithelial Cells / Q000737:chemistry / Q000276:immunology* / Q000382:microbiology; D020869:Gene Expression Profiling; D006099:Granuloma / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D016676:Macrophages, Alveolar / Q000737:chemistry / Q000276:immunology* / Q000382:microbiology; D016253:Microscopy, Immunoelectron; D009000:Monocytes / Q000737:chemistry / Q000276:immunology* / Q000382:microbiology; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D009504:Neutrophils / Q000737:chemistry / Q000276:immunology* / Q000382:microbiology; D051193:Toll-Like Receptors / Q000276:immunology; D054804:Cathelicidins
chemical_list: D023181:Antimicrobial Cationic Peptides; D051193:Toll-Like Receptors; D054804:Cathelicidins