Pulmonary alveolar proteinosis (PAP) is a rare disease of unknown aetiology characterized by accumulations of lipoproteinaceous material within the alveoli. The alveolar macrophages become increasingly foamy, and are thought to have a role in the pathogenesis of PAP. However, the mechanisms of macrophage recruitment are unclear. In the bronchoalveolar lavage fluid (BALF) of four patients with P...
