Pleural effusion disease in rabbits. Interferon in body fluids and tissues after experimental infection

The distribution of interferon in body fluids and tissues was studied in 18 rabbits infected experimentally with the agent of pleural effusion disease (PED). Circulating interferon of the classical type was demonstrable 12 h after inoculation, and a maximum response was attained 2-3 days later. Circulating interferon disappeared between 6 and 8 days after inoculation. Interferon titres of serum were closely correlated with the early phase of febrile response and probably also with the initial growth phase of the PED agent. The interferon titres of pleural fluid exceeded by far the titres of other body fluids and tissues. No interferon could be demonstrated in brain, liver and urine.