Interferon‐γ binds to heparan sulfate by a cluster of amino acids located in the C‐terminal part of the molecule

Using three different approaches (domain mapping with monoclonal antibodies, limited enzymatic digestion and competition with synthetic peptides), we demonstrated that a cluster of basic amino acids on interferon-gamma is involved in its binding to heparan sulfate. This cluster (Lys125-Arg131) is localized in the C-terminal part of IFN-gamma. Once bound to heparin sulfate, IFN-gamma is protected against protease attack.