To maintain its health, an organism must be able to repel infectious invaders. In animals, phagocytic cells—professional hunters—are essential to this process. This creates another level of challenge: how to get the phagocytic cells to the site(s) where they are needed without activating them prematurely. Several molecular events are required to orchestrate this properly. For example, endothelial cells must display appropriate adhesion proteins to supply the spatial specificity 1, and the phagocyte must be able to “smell” and respond to chemical stimuli that direct its activation and migration. Identification of the scents that attract the hunters and signals from phagocyte to phagocyte has progressed over the past two decades, and one of the first endogenous compounds to be chemically characterized was leukotriene B4 (LTB4).
In the first experiments that led to the discovery of leukotrienes,...
