In vitro killing of L. major parasites by GR1+ monocytes. GR1+ monocytes were sorted from CX3CR1GFP/+ RAG2−/− mice and plated on culture dishes. L. major parasites were added in the presence of 5% C5-deficient serum. Parasites were visualized on an inverted microscope 1 h later. Playback speed is 10× and the magnification is 400×. This movie is representative of 2 independent experiments using a total of 20 mice.