The Bad Guys of Gum Disease (image) University of Pennsylvania Caption Bacteria that cause gum disease use a sophisticated, two-prong approach to selectively disarm immune cells. The strategy prevents neutrophils from killing bacteria but still allows the cells to cause inflammation in the gums. Credit University of Pennsylvania Usage Restrictions None 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.