Matrix Metalloproteinase 9 Production by Monocytes is Enhanced by TNF and Participates in the Pathology of Human Cutaneous Leishmaniasis

Cutaneous leishmaniasis (cl) due to l.braziliensis infection is characterized by a strong inflammatory response with high levels of tnf and ulcer development. less attention has been given to the role of mononuclear phagocytes to this process. monocytes constitute a heterogeneous population subdivided into classical,intermediate and non-classical,and are known to migrate to inflammatory sites and secrete inflammatory mediators. tnf participates in the induction of matrix metalloproteinases (mmps). mmp-9 is an enzyme that degrades basal membrane and its activity is controlled by the tissue inhibitor of metalloproteinase.mononuclear cells were obtained from ex-vivo labeling sub-populations of monocytes and mmp-9,and the frequency was determined by flow cytometry. culture was performed during 72 hours,stimulating the cells with sla,levels of mmp-9 and timp-1 in the supernatants were determined by elisa.we observed that cells from cl lesions secrete high amounts of mmp-9 when compared to healthy subjects. although mmp-9 was produced by monocytes,non-classical ones were the main source of this enzyme. we also observed that tnf produced in high level during cl contributes to mmp-9 production.these observations emphasize the role of monocytes,tnf and mmp-9 in the pathogenesis of l. braziliensis infection. © 2014 campos et al.