Activating integrins isn't always "beta" for neutrophil migration!

The lungs possess extraordinary defenses against bacteria and other stimuli. Initial mechanisms of host defense include the very effective mucociliary escalator and the alveolar macrophages,which clearmany stimuli without inducing an inflammatory response and recruitment of circulating leukocytes. When these defenses are overwhelmed, epithelial cells andmacrophages call in help fromoutside the lungs. In response to bacteria, neutrophils are usually first to arrive, and their response is quick, recognizing a need within minutes