Lipoproteins in capillaries and hepatocytes of <i>Plvap</i>-deficient animals.

<p><b>A</b>, PPD-labeled granular structures fill the lumen of kidney capillaries in a 3-week-old <i>Plvap</i>^-/- mouse (arrows, boxed area, counterstain: Richardson's stain), while only erythrocytes are seen in the wild-type littermate (arrow, boxed area). <b>B</b>, The granular structures (black arrows) in the lumen of <i>Plvap</i>-deficient capillaries have diameters between 50 to 500 nm and are homogenously electron-dense. The particles are surrounded by extracellular fibrils with the ultrastructural characteristics of fibrin (white arrow) (TEM, lower panel shows higher magnification). <b>C</b>, PPD-labeled granular structures are seen in the lumen of liver sinusoids in a <i>Plvap</i>^-/- mouse but not in a wild-type littermate (white arrows). The cytoplasm of the vast majority of <i>Plvap</i>^-/- hepatocytes is densely filled with PPD-labeled granules (black arrows) which are rare in hepatocytes of wild-type littermates (black arrows). <b>D</b>, By TEM, numerous liposomes (black arrows) are seen in the <i>Plvap</i>-deficient liver indicating a pronounced microvascular steatosis. Hepatocytes of the wild-type animal contain large aggregates of glycogen (asterisks), which are absent in hepatocytes of the <i>Plvap</i>-deficient littermates. The lumen of <i>Plvap</i>^-/- liver sinusoids is occluded by fibrillar fibrin (white arrows) suggestive of thrombus formation.