Modified glycoproteins

A method of producing a preparation of recombinant glycoprotein, the method comprising:

• expressing in a cell a recombinant glycoprotein comprising a modified amino acid sequence of a reference glycoprotein, the reference glycoprotein comprising an immunoglobulin Fc region or Fc fragment,
• wherein the recombinant glycoprotein comprises an Fc region or Fc fragment comprising two amino acid substitutions relative to the Fc region or Fc fragment of the reference glycoprotein, wherein the two amino acid substitutions are F241A/F243A, F241A/K246A, F241A/T260A, F241A/R301A, F243A/K246A, F243A/T260A, F243A/R301A, K246A/T260A, K246A/R301A, or T260A/R301A, as numbered according to the EU numbering index of Kabat;
• and
• isolating the recombinant glycoprotein, thereby producing the preparation of recombinant glycoprotein, wherein the preparation has an increased level of one or more of sialylated glycans, fucosylated glycans, and N-acetylglucosamine glycans, relative to a preparation of the reference glycoprotein.