Biological and antigenic relationships between virus-induced porcine and human interferons.

Endogenous interferon (IFN) made by the newborn piglet in response to enteric coronavirus TGEV (transmissible gastroenteritis virus) infection was identified as leukocytic IFN (IFN-α). Indeed, the antiviral activity found in the serum and in the urine of infected piglets displayed the same main biological and antigenic properties as the IFN induced in influenza-infected pig leukocytes. It is therefore concluded that most, if not all, circulating IFN activity must be derived from lymphoid cells. Moreover, it was shown that a high degree of antigenic homology exists between porcine and human IFN-α: antibodies to HuIFN-α could efficiently neutralize PorIFN-α, and they were used for its purification by immunoaffinity.