Nucleic acid encoding dual Fc antigen binding proteins
The present invention relates to antigen binding proteins comprising two Fc parts, methods for their production, pharmaceutical compositions containing said antigen binding proteins, and uses thereof.
1. A method for the preparation of an antigen binding protein comprising the steps of
a) transforming an isolated host cell with isolated vectors comprising nucleic acid molecules encoding the antigen binding protein,
b) culturing the isolated host cell under conditions that allow synthesis of said antigen binding protein molecule; and
c) recovering said antigen binding protein molecule from said culture; wherein
the antigen binding protein comprises
i) two modified heavy chains of an antibody which specifically binds to an antigen, wherein VH of each heavy chain is replaced by the VL of said antibody, said modified heavy chains being associated with each other via their CH3 domains of the Fc part; and
ii) two modified heavy chains of said antibody wherein CH1 of each heavy chain is replaced by CL of said antibody, said modified heavy chains being associated with each other via their CH3 domains of the Fc part;
and wherein the VL domains of the heavy chains of i) are associated with the VH domains of the heavy chains of ii), and the CH1 domains of the heavy chains of i) are associated with the CL domains of the heavy chains of ii);
wherein the CH2 and CH3 domains of the Fc part of the modified heavy chains of i) and the CH2 and CH3 domains of the Fc part of the modified heavy chains of ii) are of the human IgG1 isotype; and
wherein either the two modified heavy chains of i), or the two modified heavy chains of ii), are further modified by the amino acid substitutions S364G, L368F, D399K and K409D, wherein the amino acid positions are numbered according to the EU Index of Kabat, and wherein the other two modified heavy chains comprise wild type CH3 amino acid sequences.
2. An isolated nucleic acid encoding an antigen binding protein, wherein
the antigen binding protein comprises
i) two modified heavy chains of an antibody which specifically binds to an antigen, wherein VH of each heavy chain is replaced by the VL of said antibody, said modified heavy chains being associated with each other via their CH3 domains of the Fc part; and
ii) two modified heavy chains of said antibody wherein CH1 of each heavy chain is replaced by CL of said antibody, said modified heavy chains being associated with each other via their CH3 domains of the Fc part;
and wherein the VL domains of the heavy chains of i) are associated with the VH domains of the heavy chains of ii), and the CH1 domains of the heavy chains of i) are associated with the CL domains of the heavy chains of ii),
wherein the CH2 and CH3 domains of the Fc part of the modified heavy chains of i) and the CH2 and CH3 domains of the Fc part of the modified heavy chains of ii) are of the human IgG1 isotype; and
wherein either the two modified heavy chains of i), or the two modified heavy chains of ii), are further modified by the amino acid substitutions S364G, L368F, D399K and K409D, wherein the amino acid positions are numbered according to the EU Index of Kabat, and wherein the other two modified heavy chains comprise wild type CH3 amino acid sequences.
3. An isolated vector comprising the isolated nucleic acid according to claim 2 .
4. An isolated host cell comprising the isolated vector according to claim 3 .
5. The method of claim 1 , wherein the antigen binding protein comprises
a) i) two modified heavy chains comprising the amino acid sequence of SEQ ID NO:1; and
ii) two modified heavy chains comprising the amino acid sequence of SEQ ID NO:2;
wherein either the two modified heavy chains of i), or the two modified heavy chains of ii), are further modified by the amino acid substitutions S364G, L368F, D399K and K409D, wherein the amino acid positions are numbered according to the EU Index of Kabat;
b) i) two modified heavy chains comprising the amino acid sequence of SEQ ID NO:3; and
ii) two modified heavy chains comprising the amino acid sequence of SEQ ID NO:4;
wherein either the two modified heavy chains of i), or the two modified heavy chains of ii), are further modified by the amino acid substitutions S364G, L368F, D399K and K409D, wherein the amino acid positions are numbered according to the EU Index of Kabat; or
b) i) two modified heavy chains comprising the amino acid sequence of SEQ ID NO:5; and
ii) two modified heavy chains comprising the amino acid sequence of SEQ ID NO:6
wherein either the two modified heavy chains of i), or the two modified heavy chains of ii), are further modified by the amino acid substitutions S364G, L368F, D399K and K409D, wherein the amino acid positions are numbered according to the EU Index of Kabat.