Abstract
•Eosinophils enhance macrophage ability to control intracellular L. amazonensis infection in vitro.•Eosinophil-driven mechanism depends on a paracrine activity mediated by soluble factor(s).•Eosinophil-secreted PGD2 mediates enhanced macrophage ability to manage L. amazonensis infection.•Macrophage DP2 receptors mediate the effect of eosinophil-derived PGD2.•Eosinophil/PGD2 may be adjuvant therapeutic option in L. amazonensis-driven diseases.
Clinical and experimental studies have described eosinophil infiltration in Leishmania amazonensis infection sites, positioning eosinophils strategically adjacent to the protozoan-infected macrophages in cutaneous leishmaniasis. Here, by co-culturing mouse eosinophils with L. amazonensis-infected macrophages, we studied the impact of eosinophils on macrophage ability to regulate intracellular L. amazonensis infection. Eosinophils prevented the increase in amastigote numbers within macrophages by a mechanism dependent on a paracrine activity mediated by eosinophil-derived prostaglandin (PG) D2 acting on DP2 receptors. Exogenous PGD2 mimicked eosinophil-mediated effect on managing L. amazonensis intracellular infection by macrophages and therefore may function as a complementary tool for therapeutic intervention in L. amazonensis-driven cutaneous leishmaniasis.