Abstract
Genentech, Inc., 460 Point San Bruno Blvd., South San Francisco, California 94080
and1 Applied Molecular Genetics, Inc. 1900 Oak Terrace Lane, Newbury Park, California 91320, U.S.A.
Recombinant DNA methodology has allowed the production of human fibroblast interferon (IFN-) from Escherichia coli and this material, in highly purified form, has been shown to reduce viraemia and mortality in encephalomyocarditis (EMC) virus-infected squirrel monkeys. These effects are dose related: six treatments over 4 days at 106 U/kg and 3 x 103 U/kg have comparable efficacy, whereas treatments at 103 U/kg are ineffective. The recombinant DNA-derived IFN- appears to be as effective as natural fibroblast cell-derived IFN- and both materials are effective by the intramuscular or intravenous routes. Thus, even though previous studies have shown that low circulating concentrations of IFN- are observed after intramuscular injections, the present data indicate that this slow release from the muscle can still confer protection.