Naturally occurring anti-interferon antibodies in Lou/c rats

Rats of the Lou/c strain have natural antibodies with binding and neutralizing activity against mouse and rat interferon. The antibodies can be purified on a column of goat IgG directed against rat IgG, and they have an affinity for protein A-Sepharose. They are already present in very young (2-wk-old) animals, and the titers increase with increasing age.