We have previously reported that the lungs of patients with very severe chronic obstructive pulmonary disease (COPD) contain significantly higher numbers of alveolar macrophages than those of non-smokers or smokers. M1 and M2 macrophages represent pro- and anti-inflammatory populations, respectively. However, the roles of M1 and M2 alveolar macrophages in COPD remain unclear. Immunohistochemica...

Alveolar macrophages play an important role in host defense and in other types of inflammatory processes in the lung. These cells exhibit many alterations in function compared with their precursor cells, blood monocytes. To evaluate a potential mechanism for these differences in function, we evaluated expression of protein kinase C (PKC) isoforms. We found an increase in Ca2+-dependent PKC isof...

Human alveolar macrophages are critical components of the innate immune system. Cigarette smoking-induced changes in alveolar macrophage gene expression are linked to reduced resistance to pulmonary infections and to the development of emphysema/COPD. We hypothesized that microRNAs (miRNAs) could control, in part, the unique messenger RNA (mRNA) expression profiles found in alveolar macrophages...

It was reported recently that the cystic fibrosis conductance regulator protein (CFTR) is required for acidification of phagosomes in alveolar macrophages (Di et al. Nature Cell Biol. 8:933–944, 2006). Here we determined whether the CFTR chloride channel is a generalized pathway for chloride entry into phagosomes of macrophages and whether mutations in CFTR could contribute to alveolar macropha...

BACKGROUND Alveolitis in pulmonary sarcoidosis is characterised by an accumulation of highly activated macrophages and CD4+ lymphocytes in the alveolar compartment. The role of intercellular adhesion molecule 1 (ICAM-1) expression on alveolar cells has been studied in this context. METHODS Using a sandwich ELISA technique, ICAM-1 expression on alveolar macrophages from 17 consecutive untreate...

Viral infections play an important role in the exacerbation of asthma. The production of interferons (IFNs) is well known to limit viral spread, but IFNg can also prime alveolar macrophages to release more inflammatory cytokines, such as tumor necrosis factora (TNFa ) and macrophage inflammatory protein-1 a (MIP-1 a ). Given the importance of these cytokines, we have investigated the effect of ...

Background. Interactions of nontypeable Haemophilus influenzae (NTHI) with human alveolar macrophages are implicated in the persistence of NTHI in chronic obstructive pulmonary disease (COPD). However, the immunologic mechanisms that mediate NTHI-induced macrophage responses are poorly understood. We hypothesized that immunologic responses of alveolar macrophages to NTHI are impaired in COPD. M...

BACKGROUND Increased pulmonary ceramide levels are suggested to play a causative role in lung diseases including COPD. Neutral sphingomyelinase-2 (nSMase-2) and acid SMase (aSMase), which hydrolyze sphingomyelin to produce ceramide, are activated by a range of cellular stresses, including inflammatory cytokines and pathogens, but notably cigarette smoke appears to only activate nSMase-2. Our pr...

Normal rabbit alveolar macrophages were infected in vitro with Candida albicans. Early after infection, germ tube formation of phagocytized C. albicans was inhibited in contrast to extracellular (nonphagocytized) C. albicans. Over and 8-h period, plate counts of C. albicans incubated with alveolar macrophages revealed a decrease in colony-forming units in contrast to C. albicans alone. In addit...

CD40-CD40 ligand (CD40L) interaction was originally defined as important molecules for the development of humoral immunity. Thereafter, some investigations have focused on its essential roles for the induction of cell-mediated immunity in host defenses. Here we investigated the antitumor activity of murine alveolar macrophages through CD40-CD40L interaction. The CD40L gene was transfected into ...