39 results about "Immunoglobulin-binding protein" patented technology

The present invention relates to immunoglobulin (Ig) binding proteins comprising one or more Ig binding domains with amino acids selected from the group consisting at least of 1I, 11A, 11E, 11I, 35R, 35I, and 42L. The invention further relates to affinity matrices comprising the Ig binding proteins of the invention. The invention also relates to a use of these Ig binding proteins or affinity matrices for affinity purification of immunoglobulins and to methods of affinity purification using the Ig binding proteins of the invention.

A multimeric immunoglobulin-binding protein having improved properties as an affinity ligand for affinity chromatography, and an insoluble support inmmobilizing such a multimer. The immunoglobulin-binding protein is represented by the formula: (R1)_n-(R2)_m, or (R2)_m-(R1)_n. R2 is an immunoglobulin-binding domain including an amino acid residue that covalently bonds to an insoluble support upon immobilization reaction with the insoluble support, and R1 is an immunoglobulin-binding domain without containing an amino acid residue the presence of which in the sequence compared to when it is absent in the sequence reduces the immunoglobulin-binding activity of the support yielded by the immobilization reaction. The immunoglobulin-binding protein satisfies: (1) n is an integer of 5 to 9; (2) m is an integer of 1 or 2; (3) the n (R1) domains may or may not have the same sequence; and (4) the total number of domains (n+m) is 6 to 10.

The invention relates to the technical field of separation and purification of immunoglobin, and relates to an immunoglobin conjugated protein and an application thereof. The immunoglobin conjugated protein is obtained by splicing E, C and Z-domain of staphylococcus protein A, improvement of antibody capacity and alkali proof characteristics are accidently obtained, and further, the immunoglobin conjugated protein can be used for affinity chromatography of the immunoglobin.

An immunoglobulin binding protein provided by the invention comprises variants of the B structural domain of a protein A, the C2 structural domain of a protein G and the B3 structural domain of a protein L or a combination of any one to three of the variants. The protein A, the protein G and the protein L have different binding characteristics and certain complementarity, so the immunoglobulin binding protein is an alkali-resistant multifunctional IBP molecule with wide reactivity and high affinity. The protein is purified by a three-step chromatography method, so that the protein quality canbe stabilized, the protein purity is more than 97%, the endotoxin level is lower than 1 Eu/mg, and the requirement of clinical protein is met. The stability of an immunoadsorption filler synthesized from the purified immunoglobulin binding protein is improved, so the use frequency of the filler can be effectively increased, and the service life of the filler is prolonged.

The present invention relates to a mutated immunoglobulin-binding protein having increased alkaline tolerance and, more specifically, to an immunoglobulin-binding protein in which, with respect to the A-domain of Staphylococcal protein A, or a functional variant thereof, an amino acid at a specific site is mutated and thereby exhibits an increased chemical stability at an alkaline pH value in comparison to a parental molecule. The present invention can provide an antibody-purifying immunoglobulin-binding protein ligand and matrix which have enhanced alkaline tolerance and accordingly enhanced stability in multiple times of alkaline cleaning.

The invention relates to the technical field of immunoglobulin separation and purification, in particular to an immunoglobulin binding protein and application thereof. The immunoglobulin binding protein is obtained by splicing partial fragments of D, C and Z-domain of staphylococcus protein A, and the binding protein with improved alkali-resistant characteristic is accidentally obtained, so that the immunoglobulin binding protein can be used for affinity chromatography of immunoglobulin.

An affinity support having improved binding capacity for target proteins. An immunoglobulin-binding protein including a mutant immunoglobulin-binding domain, an affinity support including a solid-phase support and the immunoglobulin-binding protein immobilized thereto. The mutant immunoglobulin-binding domain consists of an amino acid sequence having at least 85% identity with an amino acid sequence of any of SEQ ID NOs: 1 to 12.

The invention provides a method and a device for developing a disease marker by using an immunoglobulin-associated proteome. The invention provides a method for screening a disease marker. The method comprises a process of identifying the disease marker by using an immunoglobulin associated proteome. The method specifically comprises the following steps: separating immune globulin and binding protein in a sample by adopting a G protein cross-linked agarose bead technology; the separated protein is eluted from the magnetic beads; then carrying out trypsin digestion and desalination on the eluted protein; the desalted peptide sample is subjected to LC-MS/MS analysis by a label-free quantitative workflow. Hundreds of immunoglobulin binding proteins are quantitatively evaluated from a serum sample, a series of IgAP proteins are detected, and individuals in different health states can be classified.