Interactions between RAW macrophage and Pseudomonas aeruginosa

Macrophage is a kind of leukocyte which engulfs pathogens like bacteria through phagocytosis. However, due to mutations and physiological reactions, some bacteria are not able to be engulfed by macrophages; for example, Bacillus anthracis with poly-D-glutamate capsule protection and Salmonella which acidifies itself for camouflage. Thus, they may bring about infections in the host body. In this study, we took RAW macrophage and Pseudomonas aeruginosa (PAO1 strain), a kind of bacteria which cause pulmonary infections in patients with diseases like cystic fibrosis, as study objects, and non-macrophage U2OS cells as control group, to discover the behaviours of phagocytosis and the regulatory factors behind them. The process of phagocytosis was taken through time-lapse microscopy and analyzed by tracing the bacteria movement. Two kind of mutants for P. aeruginosa, 5017/AAA and FimX, were found to be resistant to the phagocytosis. This study would help better understanding on RAW-P. aeruginosa interactions and give some directions for future disease treatment researches.Bachelor of Science in Biological Science