Neutrophils positive to MPO in hamster and mice ALAs.

<p>Liver tissue was processed by immunohistochemistry to detect the presence of MPO in ALA of hamsters (A, C, E, G, I) and mice (B, D, F, H, J) at 3, 6, 12 and 24 h post-inoculation. Negative controls was performed with an irrelevant, antibody no label was observed (A, B). (C) Hamster liver lesions, neutrophils were positive in small inflammatory foci at 3 h post-inoculation (arrowhead). (E) At 6 h post-inoculation, amoebae (arrows) were positive to MPO. (G) At 12 h, appears extensive inflammatory reaction composed by damaged neutrophils positive to MPO. (I) At 24 h, inflammatory cells lysed on the border of a necrotic area were also stained to MPO. (D) Mouse liver lesions; inflammatory cells showed MPO label at 3 h post-inoculation (arrowhead), amoeba is seen (arrow). (F) At 6 h post-inoculation, neutrophils appear surround the damaged amoeba (arrow). (H) At 12 h appear damaged amoeba (arrow); the inflammatory infiltrate was constituted by neutrophils positive to MPO (arrowhead). (J) At 24 h staining for MPO was evident, the amoeba present signs of damage (arrow). Barr = 50μm.