Splenomegaly and elevated MK numbers in ADF/n-cofilin–null mice. (A) Spleen and body weight was measured after 9 weeks or after 5 months. Results are mean ± SD (n = 6). ***P < .001. (B) Representative spleens are shown from 9-week- or 5-month-old mice. Scale of ruler is in centimeters. (C) Numbers of MKs per visual field (328 × 246 μm) of hematoxylin and eosin stainings were determined. ***P < .001. (D) Cryo- (top panel, visual field: 1310 × 983 μm) or paraffin-embedded (bottom panel, visual field: 328 × 246 μm) sections (5 μm) were stained with anti-GPIb-HRP/hematoxylin and hematoxylin/eosin, respectively. White arrows represent MKs.