Morphological and histochemical abnormalities in the spleens of EPCR^WT/WT and EPCR^WT/R84A mice and EPCR^R84A/R84A mice. Gross anatomy (A) and weight (in grams) (B) of spleens from EPCR^R84A/R84A mice revealed severe splenomegaly compared with WT mice. Data represents the mean ± SE; n > 5 per group. Splenic sections from EPCR^R84A/R84A mice stained with H&E at low magnification (×10) (C) reveal an increase in the amount of red pulp (R) but not white pulp (W) compared with splenic sections of age-matched WT mice (D). Images representative of 3 mice per group; **P < .01.