title: Interleukin-10 plays a key role in the modulation of neutrophils recruitment and lung inflammation during infection by Streptococcus pneumoniae.
abstract: Streptococcus pneumoniae is a major aetiological agent of pneumonia worldwide, as well as otitis media, sinusitis, meningitis and sepsis. Recent reports have suggested that inflammation of lungs due to S. pneumoniae infection promotes bacterial dissemination and severe disease. However, the contribution of anti-inflammatory molecules to the pathogenesis of S. pneumoniae remains unknown. To elucidate whether the production of the anti-inflammatory cytokine interleukin-10 (IL-10) is beneficial or detrimental for the host during pneumococcal pneumonia, we performed S. pneumoniae infections in mice lacking IL-10 (IL-10(-/-) mice). The IL-10(-/-) mice showed increased mortality, higher expression of pro-inflammatory cytokines, and an exacerbated recruitment of neutrophils into the lungs after S. pneumoniae infection. However, IL-10(-/-) mice showed significantly lower bacterial loads in lungs, spleen, brain and blood, when compared with mice that produced this cytokine. Our results support the notion that production of IL-10 during S. pneumoniae infection modulates the expression of pro-inflammatory cytokines and the infiltration of neutrophils into the lungs. This feature of IL-10 is important to avoid excessive inflammation of tissues and to improve host survival, even though bacterial dissemination is less efficient in the absence of this cytokine.
authors.affiliation: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Hernán F
authors.initials: HF
authors.lastname: Peñaloza
authors.affiliation: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Pamela A
authors.initials: PA
authors.lastname: Nieto
authors.affiliation: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Natalia
authors.initials: N
authors.lastname: Muñoz-Durango
authors.affiliation: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Salazar-Echegarai
authors.affiliation: Departamento de Anatomía Patológica, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Javiera
authors.initials: J
authors.lastname: Torres
authors.affiliation: Departamento de Gastroenterología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: María J
authors.initials: MJ
authors.lastname: Parga
authors.affiliation: Departamento de Gastroenterología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Manuel
authors.initials: M
authors.lastname: Alvarez-Lobos
authors.affiliation: Millennium Institute on Immunology and Immunotherapy, Departamento de Ciencias Biológicas, Facultad de Ciencias Biológicas y Facultad de Medicina, Universidad Andrés Bello, Santiago, Chile.
authors.forename: Claudia A
authors.initials: CA
authors.lastname: Riedel
authors.affiliation: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.|Departamento de Inmunología Clínica y Reumatología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.|INSERM U1064, Nantes, France.
authors.forename: Alexis M
authors.initials: AM
authors.lastname: Kalergis
authors.affiliation: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.|INSERM U1064, Nantes, France.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Bueno
mesh_terms: D000818:Animals; D058491:Bacterial Load / Q000235:genetics / Q000276:immunology; D001921:Brain / Q000382:microbiology; D007249:Inflammation / Q000276:immunology; D007371:Interferon-gamma / Q000096:biosynthesis; D016753:Interleukin-10 / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D053583:Interleukin-1beta / Q000096:biosynthesis; D008168:Lung / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D020556:Neutrophil Infiltration / Q000276:immunology*; D009504:Neutrophils / Q000276:immunology*; D011018:Pneumonia, Pneumococcal / Q000276:immunology* / Q000401:mortality; D013154:Spleen / Q000382:microbiology; D013296:Streptococcus pneumoniae / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000276:immunology
chemical_list: C556062:IL10 protein, mouse; C587672:IL1B protein, mouse; D053583:Interleukin-1beta; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D007371:Interferon-gamma
keywords: bacterial infection; cytokines; lung inflammation; neutrophils; systemic bacterial infection