Purification of human leukocyte interferon to homogeneity with the use of a monoclonal antibody: Detailed technique and parameters

Abstract

Summary We had previously described the isolation of anti-human leukocyte interferon monoclonal antibody HBA and its use in the purification and radioimmunoassay of α interferon. The detailed procedure for this purification is described here. Human leukocyte interferon can be purified to homogeneity after two passages on an immunoadsorbant constructed with the monoclonal antibody HBA. The specific activity of the purified interferon is ≥2×10 8 IU/mg of protein. Analysis of the purified proteins by SDS-gel electrophoresis and silver-staining shows that the purified interferon consists of three species of polypeptides of different molecular weights: 18,000 for the major species and 21,000–27,000 for the minor ones. By this simple and rapid technique, it is possible to obtain pure human leukocyte interferon with good recovery (70%) from crude or partially purified preparations. Furthermore, this method could be applied to the large-scale preparation of homogeneous interferon.