Macrophages Derived from Mice and Infected with the Bacterium Francisella tularensid (video) NIH/National Institute of Allergy and Infectious Diseases Share Print E-Mail Loading video... Caption This 25-second video shows macrophages derived from mice and infected with the bacterium Francisella Tularensid. The white arrow indicates an infected cell that undergoes a sudden flash, indicating compromised host organelles, subsequent hyper-replication of the bacteria, and eventually cell death. The brown arrow indicates an uninfected 'bystander' cell that also is being killed by a similar mechanism. Images were taken every 20 minutes over 30 hours. Credit NIAID Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.