Blood Clearance of P₃₂-Labeled Vesicular Stomatitis and Newcastle Disease Viruses by the Reticuloendothelial System in Mice¹

Vesicular stomatitis virus (VSV) and Newcastle disease virus (NDV) were grown with P₃₂-containing media. P₃₂-labeled VSV was purified by ammonium sulfate precipitation and differential centrifugation, and NDV by the adsorption-elution technique with erythrocytes. Both virus preparations were shown to be cleared from the blood by the reticuloendothelial cells of the liver when injected intravenously. In the case of NDV, it was observed that previous blockade with Thorotrast slowed the rate of clearance of the virus, whereas treatment with specific antiserum increased the rate of clearance significantly.