Virus-inhibiting factor in primary and metastatic carcinoma of the liver

Sera from patients with hepatoma, metastatic liver disease, cirrhosis of the liver, and benign diseases of the digestive tract have been tested for a virus-inhibiting factor. Serum samples exerting complete inhibition of virus CPE in a dilution of at least 1:10 per 0.2 ml are considered positive, and those exerting 50% inhibition of CPE are regarded as weakly positive. An apparently positive antiviral activity was noted in the sera of patients with hepatoma (53.3%) and metastatic liver disease (46.6%). Patients with cirrhosis of the liver showed positivity in one of ten sera; no positive antiviral activity could be found in the sera of patients with benign diseases of the digestive tract. The percentage of weakly positive response was 33.3% and 13.3% for hepatoma and metastatic liver disease, respectively, and 10.0% for the benign diseases and 20.0% for the cirrhotic sera. The antiviral activity was more prominent in the embryonic foreskin fibroblasts and to a lesser degree in the bovine epithelial cells NBL-1.