Fig. 4. Enzyme-linked immunosorbent assay for albumin content in bronchoalveolar lavage fluid (BALF) of alveolar macrophage–competent and –depleted animals exposed to phosphate-buffered saline (PBS) or acid. Animals were pretreated with control liposomes (co lip) or clodronate liposomes (clodr.). After 72 h, PBS ( white bars ) or 0.1N acidic solution (HCl; black bars ), pH 1, was instilled intratracheally, and the lungs were analyzed 6 h later. Values are presented as mean ± SEM from five animals. n.s. = not significant.