Effect of pyocyanine, a pigment of Pseudomonas aeruginosa, on production of reactive nitrogen intermediates by murine alveolar macrophages.

In this study we investigated the effect of pyocyanine, a pigment produced by Pseudomonas aeruginosa, on production of reactive nitrogen intermediates by macrophages. We found that addition of pyocyanine to cultures of murine alveolar macrophages inhibited the capacity of these cells to produce reactive nitrogen intermediates (measured as nitrite) in a dose-dependent manner without altering cell viability, cytokine-induced Ia expression, or production of tumor necrosis factor.