Abstract: The present inventions provide mammalian cells that comprise multiple Stable Integration Sites. The inventions provide sites introduced genomically into a Genomic Safe Harbor and introduced genomically outside of that particular Genomic Safe Harbor, including but not limited to another Genomic Safe Harbor. Polynucleotides of interest that encode polypeptides or RNAs of interest can be inserted into the Stable Integration Sites provided according to the inventions. The cells and methods of the inventions can be used for the high yield production of any protein, including viral proteins. Additionally, the cells and methods of the inventions are useful for production of viral vectors, such as AAV, antibodies and other proteins.

Abstract: The invention provides a new expression system comprising a mammalian selectable marker that promotes desirable post-translational modifications of glycoproteins. In particular, the invention includes methods and compositions for optimal recombinant protein expression in mammalian cells by employing a selection marker system based on GPT genes of mammalian origin. The invention includes methods that facilitate selectivity and enhanced expression copies as well as protein yield of recombinant proteins in mammalian cells, and methods of using GPT expression systems.

Abstract: The invention provides a new expression system comprising a mammalian selectable marker that promotes desirable post-translational modifications of glycoproteins. In particular, the invention includes methods and compositions for optimal recombinant protein expression in mammalian cells by employing a selection marker system based on GPT genes of mammalian origin. The invention includes methods that facilitate selectivity and enhanced expression copies as well as protein yield of recombinant proteins in mammalian cells, and methods of using GPT expression systems.

Abstract: Recombinant cell surface capture proteins and detection molecules that are useful for isolating and detecting cells that produce a secreted heterodimeric protein of interest (POI) that has an immunoglobulin CH3 domain and/or substituted CH3 domain are provided. Recombinant cell surface capture proteins and detection molecules that isolate and detect bispecific antibodies are also provided. The invention also provides recombinant antigen-binding proteins that are capable of recognizing and binding to proteins of interest that contain a CH3 domain and/or a modified CH3 domain, such as a CH3 domain with or without amino acid substitutions at H95 and Y96 (IMGT).

Abstract: The present invention relates to discovery of the ectopic expression of EDEM2 in a production cell to improve the yield of a useful multi-subunit protein. Thus, the present invention provides for production cell lines, such as the canonical mammalian biopharmaceutical production cell, the CHO cell, containing recombinant polynucleotides encoding EDEM2. Also disclosed is a production cell containing both an EDEM2-encoding polynucleotide as well an XBP1-encoding polynucleotide. Improved titers of antibodies produced by these cell lines are disclosed, as well as the improved cell densities attained by these cells in culture.

Abstract: The invention provides a new expression system comprising a mammalian selectable marker that promotes desirable post-translational modifications of glycoproteins. In particular, the invention includes methods and compositions for optimal recombinant protein expression in mammalian cells by employing a selection marker system based on GPT genes of mammalian origin. The invention includes methods that facilitate selectivity and enhanced expression copies as well as protein yield of recombinant proteins in mammalian cells, and methods of using GPT expression systems.

Abstract: The invention provides a new expression system comprising a mammalian selectable marker that promotes desirable post-translational modifications of glycoproteins. In particular, the invention includes methods and compositions for optimal recombinant protein expression in mammalian cells by employing a selection marker system based on GPT genes of mammalian origin. The invention includes methods that facilitate selectivity and enhanced expression copies as well as protein yield of recombinant proteins in mammalian cells, and methods of using GPT expression systems.

Abstract: The present invention relates to discovery of the ectopic expression of EDEM2 in a production cell to improve the yield of a useful multi-subunit protein. Thus, the present invention provides for production cell lines, such as the canonical mammalian biopharmaceutical production cell, the CHO cell, containing recombinant polynucleotides encoding EDEM2. Also disclosed is a production cell containing both an EDEM2-encoding polynucleotide as well an XBP1-encoding polynucleotide. Improved titers of antibodies produced by these cell lines are disclosed, as well as the improved cell densities attained by these cells in culture.

Abstract: The present invention relates to discovery of the ectopic expression of EDEM2 in a production cell to improve the yield of a useful multi-subunit protein. Thus, the present invention provides for production cell lines, such as the canonical mammalian biopharmaceutical production cell, the CHO cell, containing recombinant polynucleotides encoding EDEM2. Also disclosed is a production cell containing both an EDEM2-encoding polynucleotide as well an XBP1-encoding polynucleotide. Improved titers of antibodies produced by these cell lines are disclosed, as well as the improved cell densities attained by these cells in culture.

Abstract: The present invention relates to discovery of the ectopic expression of EDEM2 in a production cell to improve the yield of a useful multi-subunit protein. Thus, the present invention provides for production cell lines, such as the canonical mammalian biopharmaceutical production cell—the CHO cell, containing recombinant polynucleotides encoding EDEM2. Also disclosed is a production cell containing both an EDEM2-encoding polynucleotide as well an XBP1-encoding polynucleotide. Improved titers of antibodies produced by these cell lines are disclosed, as well as the improved cell densities attained by these cells in culture.

Abstract: Recombinant cell surface capture proteins and detection molecules that are useful for isolating and detecting cells that produce a secreted heterodimeric protein of interest (POI) that has an immunoglobulin CH3 domain and/or substituted CH3 domain are provided. Recombinant cell surface capture proteins and detection molecules that isolate and detect bispecific antibodies are also provided. The invention also provides recombinant antigen-binding proteins that are capable of recognizing and binding to proteins of interest that contain a CH3 domain and/or a modified CH3 domain, such as a CH3 domain with or without amino acid substitutions at H95 and Y96 (IMGT).

Abstract: The invention provides a new expression system comprising a mammalian selectable marker that promotes desirable post-translational modifications of glycoproteins. In particular, the invention includes methods and compositions for optimal recombinant protein expression in mammalian cells by employing a selection marker system based on GPT genes of mammalian origin. The invention includes methods that facilitate selectivity and enhanced expression copies as well as protein yield of recombinant proteins in mammalian cells, and methods of using GPT expression systems.

Abstract: The present invention relates to discovery of the ectopic expression of EDEM2 in a production cell to improve the yield of a useful multi-subunit protein. Thus, the present invention provides for production cell lines, such as the canonical mammalian biopharmaceutical production cell, the CHO cell, containing recombinant polynucleotides encoding EDEM2. Also disclosed is a production cell containing both an EDEM2-encoding polynucleotide as well an XBP1-encoding polynucleotide. Improved titers of antibodies produced by these cell lines are disclosed, as well as the improved cell densities attained by these cells in culture.

Abstract: Recombinant cell surface capture proteins and detection molecules that are useful for isolating and detecting cells that produce a secreted heterodimeric protein of interest (POI) that has an immunoglobulin CH3 domain and/or substituted CH3 domain are provided. Recombinant cell surface capture proteins and detection molecules that isolate and detect bispecific antibodies are also provided. The invention also provides recombinant antigen-binding proteins that are capable of recognizing and binding to proteins of interest that contain a CH3 domain and/or a modified CH3 domain, such as a CH3 domain with or without amino acid substitutions at H95 and Y96 (IMGT).

Abstract: A method of detecting and isolating cells that produce a secreted protein of interest (POI) that has an immunoglobulin CH3 domain and/or substituted CH3 domain, comprising: a) constructing a cell line transiently or stably expressing a cell surface capture molecule, which binds the POI, by transfecting the cell line with a nucleic acid that encodes such cell surface capture molecule; b) transfecting said cell simultaneously or subsequently with a second nucleic acid that encodes a POI wherein such POI is secreted; c) detecting the surface-displayed POI by contacting the cells with a detection molecule, which binds the POI; and d) isolating cells based on the detection molecule.

Abstract: The invention provides a new expression system comprising a mammalian selectable marker that promotes desirable post-translational modifications of glycoproteins. In particular, the invention includes methods and compositions for optimal recombinant protein expression in mammalian cells by employing a selection marker system based on GPT genes of mammalian origin. The invention includes methods that facilitate selectivity and enhanced expression copies as well as protein yield of recombinant proteins in mammalian cells, and methods of using GPT expression systems.

Abstract: The present invention relates to discovery of the ectopic expression of EDEM2 in a production cell to improve the yield of a useful multi-subunit protein. Thus, the present invention provides for production cell lines, such as the canonical mammalian biopharmaceutical production cell—the CHO cell, containing recombinant polynucleotides encoding EDEM2. Also disclosed is a production cell containing both an EDEM2-encoding polynucleotide as well an XBP1-encoding polynucleotide. Improved titers of antibodies produced by these cell lines are disclosed, as well as the improved cell densities attained by these cells in culture.

Abstract: The present invention relates to discovery of the ectopic expression of EDEM2 in a production cell to improve the yield of a useful multi-subunit protein. Thus, the present invention provides for production cell lines, such as the canonical mammalian biopharmaceutical production cell—the CHO cell, containing recombinant polynucleotides encoding EDEM2. Also disclosed is a production cell containing both an EDEM2-encoding polynucleotide as well an XBP1-encoding polynucleotide. Improved titers of antibodies produced by these cell lines are disclosed, as well as the improved cell densities attained by these cells in culture.

Abstract: The present invention relates to discovery of the ectopic expression of EDEM2 in a production cell to improve the yield of a useful multi-subunit protein. Thus, the present invention provides for production cell lines, such as the canonical mammalian biopharmaceutical production cell—the CHO cell, containing recombinant polynucleotides encoding EDEM2. Also disclosed is a production cell containing both an EDEM2-encoding polynucleotide as well an XBP1-encoding polynucleotide. Improved titers of antibodies produced by these cell lines are disclosed, as well as the improved cell densities attained by these cells in culture.

Abstract: The present invention relates to discovery of the ectopic expression of EDEM2 in a production cell to improve the yield of a useful multi-subunit protein. Thus, the present invention provides for production cell lines, such as the canonical mammalian biopharmaceutical production cell—the CHO cell, containing recombinant polynucleotides encoding EDEM2. Also disclosed is a production cell containing both an EDEM2-encoding polynucleotide as well an XBP1-encoding polynucleotide. Improved titers of antibodies produced by these cell lines are disclosed, as well as the improved cell densities attained by these cells in culture.