Characterization and Separation of an Inhibitor of Viral Hemagglutination Present in Urine

SummaryNormal human urine contains a highly active inhibitor of viral hemagglutination, effective against PR8, Lee, FM1, swine, mumps, NDV, and GDVII viruses but inactive against PVM. The inhibitor concentration may approach 2 mg%. Considerable amounts of purified material, active at 0.0001 μg/cc, can be obtained readily. The activity of the inhibitor as it occurs in urine is inversely related to the salt concentration; it should be emphasized that in NaCl solutions of moderate strength it precipitates.