Early or late IL-10 blockade enhances Th1 and Th17 effector responses and promotes fungal clearance in mice with cryptococcal lung infection.
Benjamin J Murdock, Seagal Teitz-Tennenbaum, Gwo-Hsiao Chen, Anthony J Dils, Antoni N Malachowski, Jeffrey L Curtis, Michal A Olszewski, John J Osterholzer
Author Information
Benjamin J Murdock: Research Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109;
Seagal Teitz-Tennenbaum: Research Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109;
Gwo-Hsiao Chen: Research Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109;
Anthony J Dils: Research Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109;
Antoni N Malachowski: Research Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109;
Jeffrey L Curtis: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109; Pulmonary Section, Medical Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; and Graduate Program in Immunology, University of Michigan Health System, Ann Arbor, MI 48109.
Michal A Olszewski: Research Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109; Graduate Program in Immunology, University of Michigan Health System, Ann Arbor, MI 48109.
John J Osterholzer: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109; Pulmonary Section, Medical Service, Veterans Affairs Ann Arbor Healthcare System, Department of Veterans Affairs Health System, Ann Arbor, MI 48105; and Graduate Program in Immunology, University of Michigan Health System, Ann Arbor, MI 48109 oster@umich.edu.
The potent immunoregulatory properties of IL-10 can counteract protective immune responses and, thereby, promote persistent infections, as evidenced by studies of cryptococcal lung infection in IL-10-deficient mice. To further investigate how IL-10 impairs fungal clearance, the current study used an established murine model of C57BL/6J mice infected with Cryptococcus neoformans strain 52D. Our results demonstrate that fungal persistence is associated with an early and sustained expression of IL-10 by lung leukocytes. To examine whether IL-10-mediated immune modulation occurs during the early or late phase of infection, assessments of fungal burden and immunophenotyping were performed on mice treated with anti-IL-10R-blocking Ab at 3, 6, and 9 d postinfection (dpi) (early phase) or at 15, 18, and 21 dpi (late phase). We found that both early and late IL-10 blockade significantly improved fungal clearance within the lung compared with isotype control treatment when assessed 35 dpi. Immunophenotyping identified that IL-10 blockade enhanced several critical effector mechanisms, including increased accumulation of CD4(+) T cells and B cells, but not CD8(+) T cells; specific increases in the total numbers of Th1 and Th17 cells; and increased accumulation and activation of CD11b(+) dendritic cells and exudate macrophages. Importantly, IL-10 blockade effectively abrogated dissemination of C. neoformans to the brain. Collectively, this study identifies early and late cellular and molecular mechanisms through which IL-10 impairs fungal clearance and highlights the therapeutic potential of IL-10 blockade in the treatment of fungal lung infections.
References
Proc Am Thorac Soc. 2010 May;7(3):163-8
[PMID: 20463243]
