Fc variants with altered binding to FcRn
The present application relates to optimized IgG immunoglobulin variants, engineering methods for their generation, and their application, particularly for therapeutic purposes.
1. A method of producing a polypeptide comprising an Fc variant of a human IgG Fc polypeptide, wherein said Fc variant comprises an amino acid substitution at position 308, wherein said amino acid substitution is selected from the group consisting of a phenylalanine, a cysteine, a tyrosine and a tryptophan, and wherein numbering is according to the EU index in Kabat et al. said method comprising providing a cell comprising a nucleic acid encoding said polypeptide, wherein said cell is cultured under conditions suitable for expression of said polypeptide.
2. A method according to claim 1 , wherein said nucleic acid is contained in an expression vector.
3. A host cell comprising a nucleic acid encoding a polypeptide comprising an Fc variant of a human IgG Fc polypeptide, wherein said Fc variant comprises an amino acid substitution at position 308, wherein said amino acid substitution is selected from the group consisting of a phenylalanine, a cysteine, a tyrosine and a tryptophan, and wherein numbering is according to the EU index in Kabat et al.
4. An expression vector, wherein said expression vector encodes a polypeptide comprising an Fc variant, wherein said Fc variant comprises an amino acid substitution at position 308, wherein said amino acid substitution is selected from the group consisting of a phenylalanine, a cysteine, a tyrosine and a tryptophan, and wherein numbering is according to the EU index in Kabat et al.