Analysis of the liver 7 days after acute hemolysis.

(A) Liver sections of a wild-type (i) and 2 HpHx dKO mice (ii-iv) 7 days after φhyd injection stained with hematoxylin and eosin (i-ii), processed by immunohistochemistry with an anti-F4/80 antibody (iii) and stained with the Masson trichrome reaction (iv). Several leukocyte infiltrates were evident in the HpHx dKO mouse (ii). These infiltrates were strongly F4/80 positive (iii). The animal in panel iv showed massive hepatic injury with extensive fibrosis. Scale bars: i-ii, 200 μm; iii, 20 μm; iv, 100 μm. (B) Number of macrophage infiltrates per microscopic field in wild-type and HpHx dKO mice under basal condition and 7 days after φhyd injection. Macrophage infiltrates were counted on hematoxylin-and-eosin–stained sections as reported in “Materials and methods.” Four mice of each genotype were analyzed at each time point. At 7 days,P < .02.