Induces Macropinocytosis to Enter Macrophages.

is an opportunistic pathogen that infects individuals with cystic fibrosis, chronic granulomatous disease, and other immunocompromised states. survives in macrophages in membrane-bound vacuoles; however, the mechanism by which gains entry into macrophages remains unknown. After macrophage internalization, survival of within a bacteria-containing membrane vacuole (BcCV) is associated with its ability to arrest the maturation of the BcCV. In this study, we show that induces localized membrane ruffling, macropinocytosis, and macropinosomes-like compartments upon contact with the macrophage. The Type 3 Secretion System (T3SS) of contributes to macrophage entry and macropinosome-like compartment formation. These data demonstrate the ability of to enter macrophages through the induction of macropinocytosis.