In this context, as observed in cardiomyopathy, the expression levels of metalloproteinases, such as MMP-9, MMP-3 and MMP-10, produced by activated macrophages[23] can be positively regulated during this initial inflammatory process, leading to alterations in the degradation of collagen, laminin and fibronectin, to facilitate the migration of inflammatory cells to the site of infection, consequently modifying the organization of the SWP. This evidence concerns the gene MMP9 and infection.