Abstract: The present invention provides improved methods of protein purification using CEX chromatography. Such methods generally comprise the steps of: contacting a protein of interest (e.g., an antibody) with a cation exchange resin at a first pH, that is less than the pI of the most acidic isoform of the protein of interest, such that the protein of interest binds to the resin; washing the cation exchange resin at a second pH that is greater than the first pH, but less than the pI of the most acidic isoform of the protein of interest; and eluting the protein of interest from the resin at a third pH that is about equal to or less than the first pH. The methods of the invention are particularly useful for the commercial purification of recombinant therapeutic proteins (e.g., antibodies).

Abstract: The present invention provides improved methods of protein purification using CEX chromatography. Such methods generally comprise the steps of: contacting a protein of interest (e.g., an antibody) with a cation exchange resin at a first pH, that is less than the pI of the most acidic isoform of the protein of interest, such that the protein of interest binds to the resin; washing the cation exchange resin at a second pH that is greater than the first pH, but less than the pI of the most acidic isoform of the protein of interest; and eluting the protein of interest from the resin at a third pH that is about equal to or less than the first pH. The methods of the invention are particularly useful for the commercial purification of recombinant therapeutic proteins (e.g., antibodies).

Abstract: The present invention provides improved methods of protein purification using CEX chromatography. Such methods generally comprise the steps of: contacting a protein of interest (e.g., an antibody) with a cation exchange resin at a first pH, that is less than the pI of the most acidic isoform of the protein of interest, such that the protein of interest binds to the resin; washing the cation exchange resin at a second pH that is greater than the first pH, but less than the p1 of the most acidic isoform of the protein of interest; and eluting the protein of interest from the resin at a third pH that is about equal to or less than the first pH. The methods of the invention are particularly useful for the commercial purification of recombinant therapeutic proteins (e.g., antibodies).

Abstract: The present invention provides a method of increasing protein production in a cell culture by growing cells that produce the protein (e.g., the growth phase) in a perfusion cell culture to a high cell density (i.e., at least above about 40×106 cells/mL) and then switching to a protein production phase, wherein the cells are cultured in a fed-batch cell culture. The present invention further provides a method for clarifying a protein from a cell culture by adjusting the pH of the cell culture to below neutral pH (i.e., below a pH of 7) and settling the cell culture, such that the cell culture separates to form a supernatant layer and a cell-bed layer, wherein the protein is in the supernatant layer.

Abstract: The present invention provides a method of increasing protein production in a cell culture by growing cells that produce the protein (e.g., the growth phase) in a perfusion cell culture to a high cell density (i.e., at least above about 40×106 cells/N mL) and then switching to a protein production phase, wherein the cells are cultured in a fed-batch cell culture. The present invention further provides a method for clarifying a protein from a cell culture by adjusting the pH of the cell culture to below neutral pH (i.e., below a pH of 7) and settling the cell culture, such that the cell culture separates to form a supernatant layer and a cell-bed layer, wherein the protein is in the supernatant layer.

Abstract: The present invention provides methods for purifying proteins. In particular, the methods employ a two-step non-affinity chromatography process without the use of an in-process tangential flow filtration step.

Abstract: The present invention provides methods for purifying proteins. In particular, the methods employ a two-step non-affinity chromatography process without the use of an in-process tangential flow filtration step.

Abstract: Disclosed are methods relating to amplification and expression of a nucleic acid sequence encoding a polypeptide of interest in recombinant cells, and cell lines and polypeptides produced from such methods. The methods disclosed herein permit the amplification of cell lines that express a polypeptide of interest in a relatively short period of time through the use of a bioreactor.

Abstract: Disclosed are methods relating to amplification and expression of a nucleic acid sequence encoding a polypeptide of interest in recombinant cells, and cell lines and polypeptides produced from such methods. The methods disclosed herein permit the amplification of cell lines that express a polypeptide of interest in a relatively short period of time through the use of a bioreactor.

Abstract: The present invention provides a method of increasing protein production in a cell culture by growing cells that produce the protein (e.g., the growth phase) in a perfusion cell culture to a high cell density (i.e., at least above about 40×106 cells/N mL) and then switching to a protein production phase, wherein the cells are cultured in a fed-batch cell culture. The present invention further provides a method for clarifying a protein from a cell culture by adjusting the pH of the cell culture to below neutral pH (i.e., below a pH of 7) and settling the cell culture, such that the cell culture separates to form a supernatant layer and a cell-bed layer, wherein the protein is in the supernatant layer.

Abstract: The present invention provides improved methods of protein purification using CEX chromatography. Such methods generally comprise the steps of: contacting a protein of interest (e.g., an antibody) with a cation exchange resin at a first pH, that is less than the pI of the most acidic isoform of the protein of interest, such that the protein of interest binds to the resin; washing the cation exchange resin at a second pH that is greater than the first pH, but less than the pI of the most acidic isoform of the protein of interest; and eluting the protein of interest from the resin at a third pH that is about equal to or less than the first pH. The methods of the invention are particularly useful for the commercial purification of recombinant therapeutic proteins (e.g., antibodies).

Abstract: The present invention provides methods for purifying proteins. In particular, the methods employ a two-step non-affinity chromatography process without the use of an in-process tangential flow filtration step.

Abstract: The invention provides methods for a purifying protein of interest from a mixture comprising the protein of interest and one or more contaminants, including host cell DNA and proteins, by precipitation of the contaminants with caprylic acid. Such methods are particularly useful for purifying antibodies from cell cultures. Moreover, mixtures that have been depleted of contaminants using the methods of the invention can be used directly in downstream chromatography applications (e.g., ion exchange chromatography) without any further purification. These methods lead to manufacturing processes with a minimum number of unit operations and reduce the resource requirements, and thus positively influence the cost of goods for therapeutic protein production.

Abstract: The present invention provides methods for purifying proteins. In particular, the methods employ a two-step non-affinity chromatography process without the use of an in-process tangential flow filtration step.

Abstract: The invention provides methods for isolating proteins in purified form from mixtures by precipitation with citrate. The methods are advantageous in that they effectively separate a protein from lower molecular weight contaminants, including fragments or portions of the protein. Such methods are particularly useful for purifying antibodies from mixtures containing antibody proteolytic fragments and unpaired chains.

Abstract: The invention provides methods for isolating proteins in purified form from mixtures by precipitation with citrate. The methods are advantageous in that they effectively separate a protein from lower molecular weight contaminants, including fragments or portions of the protein. Such methods are particularly useful for purifying antibodies from mixtures containing antibody proteolytic fragments and unpaired chains.

Abstract: The present invention provides methods for purifying proteins. In particular, the methods employ a two-step non-affinity ion exchange chromatography process without the use of an in-process tangential flow filtration step.

Abstract: Disclosed are methods relating to amplification and expression of a nucleic acid sequence encoding a polypeptide of interest in recombinant cells, and cell lines and polypeptides produced from such methods. The methods disclosed herein permit the amplification of cell lines that express a polypeptide of interest in a relatively short period of time through the use of a bioreactor.

Abstract: The present invention provides methods for purifying proteins. In particular, the methods employ a two-step non-affinity chromatography process without the use of an in-process tangential flow filtration step.

Abstract: A method for rendering water-insoluble materials water-soluble is provided. The method is useful for solubilizing substantially water-insoluble bioactive materials such as drugs. This is accomplished by forming a non-covalently bonded complex between the drug and a polymer which is soluble in both water and an organic solvent. This is carried out by combining the desired medicinal agent with the polymer is an organic solvent, removing the solvent and dissolving the complex in water or aqueous buffer. When the organic solvent is evaporated, a solid complex is recovered which is water-soluble. Methods of treatment with the complexes are also provided.