Purification and characterization of recombinant human leukocyte interferon (IFLrA) with monoclonal antibodies.

Recombinant human leukocyte interferon produced in bacteria (IFLrA) was purified to homogeneity with the use of monoclonal antibodies against leukocyte interferon. The purified interferon exhibited a single band of Mr = approximately 19,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Amino acid analysis and the NH2-terminal sequence were consistent with the sequence predicted from the DNA. Some of the purified product contained NH2-terminal methionine; the terminal methionine was removed from the rest of the chains.