Peptide-mapping of three neutralizing epitopes into predicted biologically active sites of human interferon-alpha 2

Immunologically less reactive but functionally relevant structures were identified on human interferon (IFN)-alpha 2 by three neutralizing monoclonal antibodies (mAb). The binding sites of these mAbs were mapped using a set of synthetic peptides that covered the amino acid sequence of two predicted biologically active segments in the regions 31-53 and 63-85 of IFN-alpha 2. We measured the capacity of fragments to inhibit the IFN-neutralizing activity of mAbs and located three linear epitopes around residues 42-53, 63-76 and 77-85 of the IFN-alpha 2 molecule.