Enhancement of IgE-mediated histamine release from human basophils by viruses: role of interferon

To see if the enhancement of histamine release was related to the presence of interferon, supernatant fluids collected at the different times were assayed for interferon activity. In all control cultures there was less than 10 U interferon/0.1 ml. In contrast, the interferon titer in the supernatant fluids from cultures treated with HSV-1 rose to 20 U by 8 h and was 320 U/0.1 ml by 24 h. Table III show that histamine release is enhanced by HSV-1, Influenza A, and Sendai virus, but not by SFV-7. Between 20 and 160 U of interferorg0.1 ml were detected in the supernatant fluids from cultures treated with HSV-1, Influenza A, and Sendai virus, while less than 2 U of interferon/0.1 ml was found in supernatant fluids from cultures treated with SFV-7.