Alveolar macrophages and neutrophils mediate innate immune defense against the opportunistic fungal pathogen Aspergillus fumigatus and are believed to be essential for host survival following inhalation of fungal spores (conidia). Although alveolar macrophages are postulated to kill inhaled conidia and neutrophils are believed to act against hyphae, the relative contribution of alveolar macroph...

Alveolar macrophages constitute a primary defense against Mycobacterium tuberculosis, but they are unable to control M. tuberculosis without acquired T-cell immunity. This study determined the antigen-presenting cell function of murine alveolar macrophages and the ability of the model mycobacterium, Mycobacterium bovis BCG, to modulate it. The majority (80 to 85%) of alveolar macrophages expres...

We have reported that alpha 1-acid glycoprotein (AGP) gene expression was induced in lung tissue and in alveolar type II cells during pulmonary inflammatory processes, suggesting that local production of this immunomodulatory protein might contribute to the modulation of inflammation within the alveolar space. Because AGP may also be secreted by other cell types in the alveolus, we have investi...

The capacity of interferon-gamma to regulate the generation and release of leukotriene B4 (LTB4) from human alveolar macrophages ofnormal nonsmoking individuals was evaluated. When alveolar macrophages were incubated for 60 min with heat aggregated IgG (HAIgG), they generated and released 5.7±1.7 ng ofLT B4 per 106 cells compared to 1.9±0.4 ng from cells incubated with buffer alone, P = 0.02. W...

Inflammatory monocyte and tissue macrophages influence the initiation, progression, and resolution of type 2 immune responses, and alveolar macrophages are the most prevalent immune-effector cells in the lung. While we were characterizing the M1- or M2-like macrophages in type 2 allergic inflammation, we discovered that FoxO1 is highly expressed in alternatively activated macrophages. Although ...

Alveolar macrophages are essential for the maintenance of surfactant homeostasis. We asked whether surfactant treatment would change alveolar macrophage number and whether the alveolar macrophage phenotype would become activated or apoptotic when challenged in vivo with exogenous surfactant. Surfactant pool size in mice was increased by repetitive surfactant treatments containing 120 mg/kg (110...

BACKGROUND There is a need for novel anti-inflammatory therapies to treat COPD. The liver X receptor (LXR) is a nuclear hormone receptor with anti-inflammatory properties. METHODS We investigated LXR gene and protein expression levels in alveolar macrophages and whole lung tissue from COPD patients and controls, the effect of LXR activation on the suppression of inflammatory mediators from LP...

Pulmonary macrophages are one of the sources of various antioxidant and detoxification enzymes for which NF-E2-related factor 2 (Nrf2) is a key transcriptional factor. Although Nrf2 deficiency reportedly induces severe emphysema in smoking mice, no reports have studied Nrf2 regulation in chronic obstructive pulmonary disease (COPD). In this study, Nrf2 activation in response to cigarette smoke ...

Infection of sheep by visna-maedi virus causes an interstitial pneumonitis similar to that associated with human immunodeficiency virus type-1 (HIV-1). Visna-maedi virus infection of alveolar macrophages leads to their activation. In this study we determined whether an imbalance in oxidant-antioxidant activity may be involved in the pathogenesis of the disease. We investigated the spontaneous a...