Serum levels of alpha and gamma interferons in hemorrhagic fever with renal syndrome

Hemorrhagic fever with renal syndrome is an acute viral disease caused by Hantavirus. On the basis of clinical observation, the illness is divided into five sequential stages: febrile, hypotensive, oliguric, diuretic, and convalescent. Because interferons can be induced by viruses, and because their stimulating effects on immune cells can alter the course of viral infections, we examined the presence of alpha interferon (IFN-α) and gamma interferon (IFN-γ) in 276 serum samples collected from 110 patients during the Korean Conflict. We tested these sera for IFN-α by bioassay with bovine kidney MDBK cells, and for IFN-γ by a sandwich ELISA with antibodies specific for human IFN-γ. We found variable, but persistently elevated levels of IFN-γ throughout the various phases of the disease, which suggested persistent immune activation through convalescence. Moderate levels of IFN-α were found in all stages of infection.