(43) found that continuous LPS stimulation impaired zymosan phagocytosis by peritoneal macrophages in vivo. These data indicate that many factors (such as HMGB1 and LPS) within the BALF might directly impact the ability of macrophages to perform phagocytosis on apoptotic cells in the ALI/ARDS model. This evidence concerns the gene HMGB1 and acute respiratory distress syndrome.