title: Opposing roles of IL-10 in acute bacterial infection.
abstract: Interleukin-10 (IL-10) is recognized as an anti-inflammatory cytokine that downmodulates inflammatory immune responses at multiple levels. In innate cells, production of this cytokine is usually triggered after pathogen recognition receptor (PRR) engagement by pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patters (DAMPs), as well as by other soluble factors. Importantly, IL-10 is frequently secreted during acute bacterial infections and has been described to play a key role in infection resolution, although its effects can significantly vary depending on the infecting bacterium. While the production of IL-10 might favor host survival in some cases, it may also result harmful for the host in other circumstances, as it can prevent appropriate bacterial clearance. In this review we discuss the role of IL-10 in bacterial clearance and propose that this cytokine is required to recover from infection caused by extracellular or highly pro-inflammatory bacteria. Altogether, we propose that IL-10 drives excessive suppression of the immune response upon infection with intracellular bacteria or in non-inflammatory bacterial infections, which ultimately favors bacterial persistence and dissemination within the host. Thus, the nature of the bacterium causing infection is an important factor that needs to be taken into account when considering new immunotherapies that consist on the modulation of inflammation, such as IL-10. Indeed, induction of this cytokine may significantly improve the host's immune response to certain bacteria when antibiotics are not completely effective.
authors: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Chile.
authors: Hernán F
authors: HF
authors: Peñaloza
authors: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Chile.
authors: Barbara M
authors: BM
authors: Schultz
authors: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Chile.
authors: Pamela A
authors: PA
authors: Nieto
authors: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Chile.
authors: Geraldyne A
authors: GA
authors: Salazar
authors: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Chile.
authors: Isidora
authors: I
authors: Suazo
authors: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Chile.
authors: Pablo A
authors: PA
authors: Gonzalez
authors: Millennium Institute on Immunology and Immunotherapy, Departamento de Ciencias Biológicas, Facultad de Ciencias Biológicas y Facultad de Medicina, Universidad Andrés Bello, Chile.
authors: Claudia A
authors: CA
authors: Riedel
authors: Departamento de Gastroenterología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Chile.
authors: Manuel M
authors: MM
authors: Alvarez-Lobos
authors: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Chile; Departamento de Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Chile; INSERM U1064, Nantes, France.
authors: Alexis M
authors: AM
authors: Kalergis
authors: Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Chile; INSERM U1064, Nantes, France. Electronic address: sbueno@bio.puc.cl.
authors: Susan M
authors: SM
authors: Bueno
mesh_terms: D000818:Animals; D001424:Bacterial Infections / Q000276:immunology*; D006801:Humans; D007113:Immunity, Innate; D016753:Interleukin-10 / Q000276:immunology*; D012141:Respiratory Tract Infections / Q000276:immunology; D015398:Signal Transduction
chemical_list: D016753:Interleukin-10
keywords: Acute bacterial infection; Extracellular bacteria; Inflammation severity; Innate immunity; Interleukin-10; Intracellular bacteria