[The role of iron in the interaction between host and pathogen]

Iron is essential for both pathogenic microbes and their host. Iron status may influence the occurrence and outcome of infections. For many microorganisms, iron is essential for growth, survival, and synthesis of virulence factors. However, because circulating iron is mostly transported bound to proteins and the level of free serum iron is therefore very low, some pathogens have developed complex systems to acquire iron efficiently. Understanding these systems is essential in the design of pharmaceutical agents and vaccines targeting pathogens with iron-linked virulence. In this review, we examine current data on the role of iron in the struggle between host and pathogen to regulate levels of this essential element. We hope that, in the near future, treatments aimed at reducing iron overload will improve the response to current therapies, and help control infection.