Abstract: The present invention provide novel immunofiber compositions for protein or peptide purification and simple and cost-efficient methods and systems using these compositions. In some embodiments, the immunofibers comprise a customized Z-33 peptide derived from Staphylococcus aureus Protein A which is used to construct immuno-amphiphile molecules that assemble into immunofibers in aqueous solution with bioactive epitopes on the surface and have peptide or protein binding ability.

Abstract: The invention provides improved methods of regenerating and using affinity chromatography resin, in particular Protein A affinity chromatography resins.

Abstract: The present disclosure relates to the use of host cell protein biomarkers to assess disulfide bond reduction in compositions comprising a protein of interest. In some embodiments, the disclosure relates to methods of predicting the occurrence of disulfide bond reduction or low molecular weight protein species in compositions comprising a protein of interest, wherein the expression or activity level of at least one host cell protein is measured and provides a benchmark value associated with the occurrence of disulfide bond reduction or low molecular weight species of said protein of interest. In some embodiments, the disclosure relates to methods of producing a protein of interest, wherein host cells capable of producing the protein of interest are cultured, the expression or activity level of at least one host cell protein is measured, and downstream isolation of the protein of interest is informed by the host cell protein measurements.

Abstract: In certain embodiments, the present invention provides a method of measuring the level of hydrophobicity of a chromatographic resin. In certain embodiments, the present invention provides a method of selecting a chromatographic resin condition for purifying a protein of interest from a mixture, wherein the protein of interest has low or no aggregation formation during chromatography. In certain embodiments, the present invention provides a method of selecting a chromatographic resin from a plurality of chromatographic resins for purifying a protein of interest from a mixture, wherein the protein of interest has low or no aggregation formation during chromatography.

Abstract: The disclosure is directed to systems and methods for purifying proteins containing an Fc region, such as antibodies or Fc fusion proteins. The system includes one or more filler molecules comprising a linear hydrocarbon chain conjugated to a peptide amino acid sequence, and one or more ligand molecules comprising a linear hydrocarbon chain, a peptide amino acid sequence, a linker, and a Z33 peptide of Staphylococcus aureus Protein A. The filler molecules and ligand molecules self-assemble into immunofibers (IFs) under physiological conditions.

Abstract: The present invention provide novel immunofiber compositions for protein or peptide purification and simple and cost-efficient methods and systems using these compositions. In some embodiments, the immunofibers comprise a customized Z-33 peptide derived from Staphylococcus aureus Protein A which is used to construct immuno-amphiphile molecules that assemble into immunofibers in aqueous solution with bioactive epitopes on the surface and have peptide or protein binding ability.

Abstract: In some embodiments, the present invention provides a method of purifying a protein of interest with a reduced level of aggregation formation in cation exchange (CEX) chromatography, comprising: (a) providing a mixture comprising the protein of interest and one or more contaminants; (b) loading the mixture onto a CEX resin coupled with arginine; and (c) eluting the protein of interest from the resin, thereby purifying the protein of interest with a reduced level of aggregation formation in CEX chromatography.

Abstract: In some embodiments, the present invention provides a method of purifying a protein of interest with a reduced level of aggregation formation in cation exchange (CEX) chromatography, comprising: (a) providing a mixture comprising the protein of interest and one or more contaminants; (b) loading the mixture onto a CEX resin coupled with arginine; and (c) eluting the protein of interest from the resin, thereby purifying the protein of interest with a reduced level of aggregation formation in CEX chromatography.

Abstract: The present invention provide novel immunofiber compositions for protein or peptide purification and simple and cost-efficient methods and systems using these compositions. In some embodiments, the immunofibers comprise a customized Z-33 peptide derived from Staphylococcus aureus Protein A which is used to construct immuno-amphiphile molecules that assemble into immunofibers in aqueous solution with bioactive epitopes on the surface and have peptide or protein binding ability.

Abstract: In certain embodiments, the present invention provides novel antibody purification methods and systems using a potentially simple and cost-efficient means. In some embodiments, customized Z-33 derived from Staphylococcus aureus Protein A is used to construct immuno-amphiphile molecules which can assemble into immunofibers in aqueous solution with bioactive epitopes on the surface and have IgG binding ability.

Abstract: In certain embodiments, the disclosure provides an IgG4 antibody comprising a heavy chain and a light chain, wherein the heavy chain comprises: (a) a modified IgG4 CH1 region having a substitution of the lysine residue at position 196; or (b) a modified IgG4 hinge region having a substitution of the serine residue at position 217, the glycine residue at position 220, the proline residue at position 224 or the proline residue at position 225. Preferably, the IgG4 antibody further comprises a substitution of the serine residue at position 228 in the heavy chain hinge region.

Abstract: The invention provides improved methods of regenerating and using affinity chromatography resin, in particular Protein A affinity chromatography resins.

Abstract: In certain embodiments, the present invention provides novel antibody purification methods and systems using a potentially simple and cost-efficient means. In some embodiments, customized Z-33 derived from Staphylococcus aureus Protein A is used to construct immuno-amphiphile molecules which can assemble into immunofibers in aqueous solution with bioactive epitopes on the surface and have IgG binding ability.

Abstract: In certain embodiments, the present invention provides a method of measuring the level of hydrophobicity of a chromatographic resin. In certain embodiments, the present invention provides a method of selecting a chromatographic resin condition for purifying a protein of interest from a mixture, wherein the protein of interest has low or no aggregation formation during chromatography. In certain embodiments, the present invention provides a method of selecting a chromatographic resin from a plurality of chromatographic resins for purifying a protein of interest from a mixture, wherein the protein of interest has low or no aggregation formation during chromatography.

Abstract: In some embodiments, the present invention provides a method of purifying a protein of interest with a reduced level of aggregation formation in cation exchange (CEX) chromatography, comprising: (a) providing a mixture comprising the protein of interest and one or more contaminants; (b) loading the mixture onto a CEX resin coupled with arginine; and (c) eluting the protein of interest from the resin, thereby purifying the protein of interest with a reduced level of aggregation formation in CEX chromatography.

Abstract: This disclosure provides a method of purifying proteins using a combined AEX-CEX chromatography in flow-through mode under an operating condition wherein no automation, engineering control, and/or in-line adjustment is used between the AEX and the CEX. The AEX and CEX (or CEX and AEX) can be connected directly.

Abstract: In some embodiments, the present invention provides a method of purifying a protein of interest with a reduced level of aggregation formation in cation exchange (CEX) chromatography, comprising: (a) providing a mixture comprising the protein of interest and one or more contaminants; (b) loading the mixture onto a CEX resin coupled with arginine; and (c) eluting the protein of interest from the resin, thereby purifying the protein of interest with a reduced level of aggregation formation in CEX chromatography.

Abstract: The present disclosure relates to the use of host cell protein biomarkers to assess disulfide bond reduction in compositions comprising a protein of interest. In some embodiments, the disclosure relates to methods of predicting the occurrence of disulfide bond reduction or low molecular weight protein species in compositions comprising a protein of interest, wherein the expression or activity level of at least one host cell protein is measured and provides a benchmark value associated with the occurrence of disulfide bond reduction or low molecular weight species of said protein of interest. In some embodiments, the disclosure relates to methods of producing a protein of interest, wherein host cells capable of producing the protein of interest are cultured, the expression or activity level of at least one host cell protein is measured, and downstream isolation of the protein of interest is informed by the host cell protein measurements.

Abstract: The present invention provide novel immunofiber compositions for protein or peptide purification and simple and cost-efficient methods and systems using these compositions. In some embodiments, the immunofibers comprise a customized Z-33 peptide derived from Staphylococcus aureus Protein A which is used to construct immuno-amphiphile molecules that assemble into immunofibers in aqueous solution with bioactive epitopes on the surface and have peptide or protein binding ability.

Abstract: In certain embodiments, the disclosure provides an IgG4 antibody comprising a heavy chain and a light chain, wherein the heavy chain comprises: (a) a modified IgG4 CH1 region having a substitution of the lysine residue at position 196; or (b) a modified IgG4 hinge region having a substitution of the serine residue at position 217, the glycine residue at position 220, the proline residue at position 224 or the proline residue at position 225. Preferably, the IgG4 antibody further comprises a substitution of the serine residue at position 228 in the heavy chain hinge region.