Abstract: The present disclosure relates to mammalian cells (e.g., Chinese Hamster Ovary (CHO) cells) that are modified to reduce or eliminate the expression of certain mammalian cell endogenous products (e.g., host cell proteins and virus-like particles), and methods of using such cells in the production of a recombinant product of interest, e.g., a recombinant protein, a recombinant viral particle, or a recombinant viral vector. These modifications were specifically chosen to generate engineered mammalian host cells with desired traits in several key areas, including improved cell culture performance (e.g., higher viability and product titers), improved product quality (e.g., more consistent and favorable glycosylation; more stable drug product), and decreased burden on purification for removing problematic or undesired endogenous host cell products (e.g., hydrolytic host cell proteins and virus-like particles) during biomanufacturing.

Abstract: Herein are reported modified mammalian cells wherein the expression of the MYC gene and one or more of the BAK, BAX, SIRT-1 and ICAM-1 genes has been reduced or eliminated as well as methods for the recombinant production of a heterologous polypeptide using a modified mammalian cell according to the current invention. Further reported are use of the reduction of the expression of the genes for increasing volumetric productivity, increasing cell volume, increasing viability and increasing the possible cultivation time without cell split.

Abstract: Herein a modular and efficient method for cloning multigene plasmids containing only a single cloning step without the use of preliminary single-gene vectors is reported. In the first step, PCR-produced DNAblocks carrying genes for different antibody chains are ligated with the respective adaptors, which serve as connectors of the different DNAblocks. In the second step, the PCR-produced fragments of the first step are assembled in the correct arrangement via the unique recombination sites located at one end of each backbone, DNAblock and adaptor fragment. This new strategy results in a modular and efficient method, which allows direct cloning of expression cassettes into the respective backbone without intermediate cloning steps and enable fast cloning of variable gene configurations of diverse antibody formats. This new cloning method according to the current invention provides considerable advantages in terms of time, work labor and costs.

Abstract: Herein is reported a method for generating a recombinant mammalian cell expressing a heterologous polypeptide and a method for producing a heterologous polypeptide using said recombinant mammalian cell, wherein in the recombinant cell the expression of the endogenous SIRT-1 gene has been reduced. It has been found that the knockout of the sirtuin-1 gene (SIRT-1) in mammalian cells, e.g. such as CHO cells, improves recombinant productivity and reduces lactate production by the cells. Additionally, it has been found that the viability decline at the end of a fed-batch fermentation is reduced.

Abstract: Herein is reported a method for producing a recombinant mammalian cell comprising a deoxyribonucleic acid encoding a polypeptide and secreting the polypeptide comprising the steps of a) providing a mammalian cell comprising an exogenous nucleotide sequence integrated at a single site within a locus of the genome of the mammalian cell, wherein the exogenous nucleotide sequence comprises a first and a second recombination recognition sequence flanking at least one first selection marker, and a third recombination recognition sequence located between the first and the second recombination recognition sequence, and all the recombination recognition sequences are different; b) introducing into the cell provided in a) a composition of two deoxyribonucleic acids comprising three different recombination recognition sequences and one to eight expression cassettes, wherein the first deoxyribonucleic acid comprises in 5?- to 3?-direction, a first recombination recognition sequence, one or more expression cassette(s), a

Abstract: Herein is reported a method for producing a bivalent, bispecific antibody comprising the steps of cultivating a mammalian cell comprising a deoxyribonucleic acid encoding the bivalent, bispecific antibody, and recovering the bivalent, bispecific antibody from the cell or the cultivation medium, wherein the deoxyribonucleic acid encoding the bivalent, bispecific antibody is stably integrated into the genome of the mammalian cell and comprises in 5?- to 3?-direction either a first expression cassette encoding the first light chain, a second expression cassette encoding the first heavy chain, a third expression cassette encoding the second light chain, and a fourth expression cassette encoding the second heavy chain, or a first expression cassette encoding the first light chain, a second expression cassette encoding the second heavy chain, a third expression cassette encoding the second light chain, and a fourth expression cassette encoding the first heavy chain, wherein the first heavy chain comprises from N- t

Abstract: Herein are reported novel DNA constructs and methods using the same. The current invention uses a deliberate arrangement of non-productive/inactive promoters and genes on coding and template strands of DNA molecules, which are converted into their active form by the interaction with a site-specific recombinase. In more detail, the DNA element according to the current invention is non-functional with respect to the expression of the contained first and second genes. By being non-functional with respect to the expression of the first and second gene, the DNA element according to the invention can be integrated into genome of a cell without the risk that the comprised structural genes are expressed already directly after the integration. The genes are only expressed once a recombinase recognizing and functional with the recombination recognition sequences of the DNA element is activated or introduced into the cell.

Abstract: Herein is reported a method for generating a recombinant mammalian cell expressing a heterologous polypeptide and a method for producing a heterologous polypeptide using said recombinant mammalian cell, wherein in the recombinant cell the expression of at least the endogenous gene MYC has been reduced. It has been found that the knockout of at least the endogenous gene MYC in mammalian cells, e.g. such as CHO cells, improves recombinant productivity by the cells.

Abstract: Herein is reported a novel adenoviral VA RNA nucleic acid wherein the wild-type type 2 polymerase III promoter has been removed and an U6-snRNA promoter or an inducible promoter has been added.

Abstract: The invention relates to vectors and mammalian cells in a system useful for switching on or switching off gene expression in response to pH and gaseous carbon dioxide, taking advantage of signal transduction of the human proton-activated cell-surface receptor TDAG8, OGR1 and/or GPR4 and related receptors to chimeric promoters containing cAMP-response elements. The systems according to the invention can be used to precisely monitor culture pH within the physiologic range, or also to adjust expression by gaseous C02 which shifts the C02-bicarbonate balance towards hydrogen ions. Production of biopharmaceuticals of engineered cells cultivated in a bioreactor setup can be induced by gaseous C02. Also, implanting engineered cells provide novel treatment strategies for acidosis-related disorders and type 1 diabetes.