NLRP3 and infection: This we observed in C57Bl/6-derived BMDMs as well as after infection of human cells, which may indicate a role in the circumvention of a host protective mechanism by Leishmania. In PMA-differentiated THP-1 cells as well as in LPS-primed macrophages, L. major and L. mexicana inhibited NLRP3 inflammasome activation as indicated by reduced levels of secreted IL-1β.