Research Highlight Macrophage Metalloelastase: Stretching Therapeutic Opportunities

While tissue macrophages are at the first line of microbial host defense, they are also convenient hideouts for pathogens escaping immune attack. Houghton et al. discovered that alveolar macrophage mobilizes macrophage metalloelastase to destroy bacteria present inside the cell. Owing to their low numbers in peripheral blood and lymphoid organs, tissue resi-dent macrophages have not always received the level of attention they deserve. Only recently did tissue macro-phages take center stage based on their implication in a wide range of disease indi-cations including tumor growth and metas-tasis, autoimmunity and wound healing (Gordon, 2007). These indications are often secondary to the macrophages’ prime mission to protect host agains