Role of Prostaglandin F2α Production in Lipid Bodies From Leishmania infantum chagasi: Insights on Virulence

Lipid bodies (LB; lipid droplets) are cytoplasmic organelles involved in lipid metabolism. Mammalian LBs display an important role in host-pathogen interactions, but the role of parasite LBs in biosynthesis of prostaglandin F-2 alpha (PGF(2 alpha)) has not been investigated. We report herein that LBs increased in abundance during development of Leishmania infantum chagasi to a virulent metacyclic stage, as did the expression of PGF(2 alpha) synthase (PGFS). The amount of parasite LBs and PGF(2 alpha) were modulated by exogenous arachidonic acid. During macrophage infection, LBs were restricted to parasites inside the parasitophorous vacuoles (PV). We detected PGF(2 alpha) receptor (FP) on the Leishmania PV surface. The blockage of FP with AL8810, a selective antagonist, hampered Leishmania infection, whereas the irreversible inhibition of cyclooxygenase with aspirin increased the parasite burden. These data demonstrate novel functions for parasite-derived LBs and PGF(2 alpha) in the cellular metabolism of Leishmania and its evasion of the host immune response.