This interspecific difference showing that L. infantum induced greater phagocytic capacity and production of NO and TNF-a by human monocytes compared to L. braziliensis. In the literature, studies point to the existence of polymorphisms in the structure of LPG intra and interspecies of Leishmania. 28,29 Polymorphisms of the glycoconjugates (LPG, GIPLs and gp63), are important in the differential regulation of the initial events of the immune response, as well as in the establishment of the infection. This evidence concerns the gene TNF and infection.