Abstract: AIM: To observe the effect of phagotrophic ability of macrophage on pseudomonas aeruginosa which was cocultured with low concentration of erythromycin.METHODS: The pseudomonas aeruginosa ATCC 27853 was cultured in LB both with low concentration of erythromycin (GrouPA) and without erythromycin (GrouPB) for 18 h separately, then incubated with macrophage from murine abdominal cavity for 2 h.The ratio of phagocytosis of macrophage was determined by microscope detection.RESULTS: The ratio of phagocytosis of grouPA in which erythromycin was added was higher than the grouPB, and the pseudopodia of macrophage were increased in the grouPA under electron microscope.CONCLUSION: Low concentration of erythromycin may enhance the phagocytosis ability of macrophage in vitro by influencing the virulent factors of PA.

Key words: erythromycin, pseudomonas aeruginosa, macrophage