Histopathologic analysis of band 3 null mice. Band 3 null pups and organs from band 3 null adult mice were fixed in buffered formalin for histopathologic examination. Tissues were stained with hematoxylin and eosin. (A and B) (original magnification × 20) show characteristic thrombi in the atrial and ventricular cavities. Similar lesions were observed in nine of 12 mice examined. A higher magnification of one thrombus in (C) (original magnification × 60) clearly shows endothelial lining of the organized thrombus, indicating premortem development of the lesion. (D) (original magnification × 40) shows two thrombi in a medium-size vessel in the lung parenchyma. (E) (original magnification × 40) shows a large organized thrombus in the portal vein in one adult band 3 null mouse. (F) (original magnification × 40) shows a liver section from a band 3 null pup revealing subcapsular hepatocellular necrosis suggesting an ischemic event due to a small arterial occlusion. M, myocardium; T, thrombus; RA, right atrium; RV, right ventricle; LA, lung alveoli; H, hepatocytes; N, necrosis.