The present invention relates to polypeptides with reduced immune response including reduced allergenicity having one or more amino acid residues being substituted with other amino acid residues and/or having coupled one or more polymeric molecules in the vicinity of the polypeptides metal binding site, a method for preparing modified polypeptides of the invention, the use of the polypeptide for reducing the immunogenicity and allergenicity and compositions comprising the polypeptide.