Different effects of influenza virus, respiratory syncytial virus, and Sendai virus on human lymphocytes and macrophages.

Influenza virus, respiratory syncytial virus, and Sendai virus depress human cell-mediated immune responses, such as mitogen-induced lymphocyte transformation, but differ in their ability to induce other immune defense mechanisms, such as interferon production. Exposure to the different viruses resulted in depressed transformation responses to the mitogen phytohemagglutinin by affecting the function of lymphocytes, or macrophages, or both cell types.