We also found that ROS generation depended on CCL3 and was required for killing of Lm. In the present work, taking advantage of the same experimental settings in which the vast majority of bacteria were found inside phagocytic cells of the spleen [22]–[23], we investigated the modulation of the antimicrobial effector activities expressed by innate phagocytes in the course of the secondary infection and the impact this have on the clearance of the bacteria from infected tissues. The gene discussed is CCL3; the disease is infection.