Phosphatidylserine Exposure and Surface Sugars in Two Leishmania (Viannia) braziliensis Strains Involved in Cutaneous and

Background. Phosphatidylserine (PS) and surface carbohydrates (SC) are known as virulence factors that may contribute to the different clinical symptoms ranging from self-healing cutaneous leishmaniasis lesions to fatal visceral disease. Leishmania (Viannia) braziliensis causes localized cutaneous leishmaniasis (LCL) and mucocuta-neous leishmaniasis (MCL). Methods. We analyzed PS exposure and SC expression associated with 2 primary L. braziliensis isolates from patients with LCL or MCL. The role of PS exposure was also addressed during promastigotes phagocytosis by macrophages. Results. We observed higher PS exposure on the surface of late stationary growth phase promastigotes from patients with LCL, compared with those from patients with MCL, and both strains were alive during PS display. Reduction in the infectivity index was observed during macrophage interaction with late stationary growth phase promastigotes in which PS was blocked by annexin V. The major surface carbohydrates detected on LCL and MCL promastigotes were α-Man, α-Glc, and α-Gal. However, α-β-GalNAc, although observed on the surface of the LCL strain during the late stationary growth phase was highly expressed on the surface of early stationary growth phase promastigotes