Leukotrienes Produced in Allergic Lung Inflammation Activate Alveolar Macrophages

Author(s)

Silva, Reinaldo C. ; Landgraf, Maristella A. ^[1] ; Hiyane, Meire I. ^[1] ; Pacheco-Silva, Alvaro ; Camara, Niels O. ^[1] ; Landgraf, Richardt G. ^{[2, 3]}

Affiliation

^[1] Univ Sao Paulo, Dept Imunol, Lab Imunol Transplantes, Sao Paulo - Brazil

^[2] Univ Fed Sao Paulo, Disciplina Nefrol, Dept Nefrol, Lab Imunol Clin & Expt, BR-04023900 Sao Paulo - Brazil

^[3] Univ Fed Sao Paulo, Dept Ciencias Biol, BR-04023900 Sao Paulo - Brazil

• Document type: Journal article
• Source: CELLULAR PHYSIOLOGY AND BIOCHEMISTRY; v. 26, n. 3, p. 319-326, 2010.
• Web of Science Citations: 8

Abstract

It has been well-documented that leukotrienes (LTs) are released in allergic lung inflammation and that they participate in the physiopathology of asthma. A role for LTs in innate immunity has recently emerged: Cys-LTs were shown to enhance Fc gamma R-mediated phagocytosis by alveolar macrophages (AMs). Thus, using a rat model of asthma, we evaluated Fc gamma R-mediated phagocytosis and killing of Klebsiella pneumoniae by AMs. The effect of treatment with a cys-LT antagonist (montelukast) on macrophage function was also investigated. Male Wistar rats were immunized twice with OVA/alumen intraperitoneally and challenged with OVA aerosol. After 24 h, the animals were killed, and the AMs were obtained by bronchoalveolar lavage. Macrophages were cultured with IgG-opsonized red blood cells (50: 1) or IgG-opsonized K. pneumoniae (30: 1), and phagocytosis or killing was evaluated. Leukotriene C(4) and nitric oxide were quantified by the EIA and Griess methods, respectively. The results showed that AMs from sensitized and challenged rats presented a markedly increased phagocytic capacity via Fc gamma R (10X compared to controls) and enhanced killing of K. pneumoniae (4X higher than controls). The increased phagocytosis was inhibited 15X and killing 3X by treatment of the rats with montelukast, as compared to the non-treated group. cys-LT addition increased phagocytosis in control AMs but had no effect on macrophages from allergic lungs. Montelukast reduced nitric oxide (39%) and LTC(4) (73%). These results suggest that LTs produced during allergic lung inflammation potentiate the capacity of AMs to phagocytose and kill K. pneumonia via Fc gamma R. Copyright (C) 2010 S. Karger AG, Basel (AU)

• FAPESP's process: 07/07139-3 - The role of heme oxygenase 1 in different renal inflammatory process in experimental animal models
• Grantee: Niels Olsen Saraiva Câmara
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 10/01404-0 - In vivo and in vitro studies of the leptin role in different models of lung inflammation: inflammatory mediators and signaling airways participation
• Grantee: Richardt Gama Landgraf
• Support Opportunities: Research Grants - Young Investigators Grants