Figure 6: Scanning electron microscopy of the interaction of A. castellanii trophozoites with hamster cornea. (a) At 1 h, one trophozoite was observed penetrating the most superficial epithelial cells. Bar = 10 μm. (b) Trophozoite (T) emitting a phagocytic structure (arrow) was a frequent event. Bar = 10 μm. (c) After 2 h of interaction numerous trophozoites were located under the first layer of the corneal epithelium. Bar = 20 μm. (d) By 4 h A. castellanii continued migrating towards the deepest layers of the corneal epithelium (arrow). Bar = 10 μm. (e) At 16 h, numerous trophozoites remained adhered to the surface of the epithelial cells that had not been detached. Bar = 20 μm. (f) After 24 h damage to the structure of the cornea is evident. A trophozoite was observed apparently phagocyting an epithelial cell (arrow). Bar = 20 μm.