44 results about "IgG binding" patented technology

Antibodies to heavy chain of human FcRn are provided which function as non-competitive inhibitors of IgG binding to FcRn. The antibodies may be polyclonal, monoclonal, chimeric or humanized, or antigen binding fragments thereof. These antibodies are useful for reducing the concentration of pathogenic IgGs in individuals and therefore used as a therapeutic tool in autoimmune and alloimmune conditions.

Provided is a peptide capable of binding to human IgG specifically or selectively. A peptide characterized by comprising an amino acid sequence represented by formula (I): (X1-3)-C-(X2)-H-R-G-(Xaa1)-L-V-W-C-(X1-3) (wherein Xs independently represent an arbitrary amino acid residue other than a cysteine residue; C represents a cysteine residue; H represents a histidine residue; R represents an arginine residue; G represents a glycine residue; Xaa1 represents a glutamic acid residue or an asparagine residue; L represents a leucine residue; V represents a valine residue; and W represents a tryptophan residue) and composed of 13-17 amino acid residues, and also characterized by being capable of binding to human IgG.

It has been determined that allergens, which are characterized by both humoral (IgE) and cellular (T cell) binding sites, can be modified to be less allergenic by modifying the IgE binding sites. The IgE binding sites can be converted to non-IgE binding sites by masking the site with a compound that prevents IgE binding or by altering as little as a single amino acid within the protein, most typically a hydrophobic residue towards the center of the IgE-binding epitope, to eliminate IgE binding. The method allows the protein to be altered as minimally as possible, other than-within the IgE-binding sites, while retaining the ability of the protein to activate T cells, and, in some embodiments by not significantly altering or decreasing IgG binding capacity The examples use peanut allergens to demonstrate alteration of IgE binding sites. The critical amino acids within each of the IgE binding epitopes of the peanut protein that are important to immunoglobulin binding have been determined. Substitution of even a single amino acid within each of the epitopes led to loss of IgE binding. Although the epitopes shared no common amino acid sequence motif, the hydrophobic residues located in the center of the epitope appeared to be most critical to IgE binding.

The present invention pertains to: an IgG-binding peptide containing a ligand which can be bound to a radioactive metal nuclide; an IgG-binding peptide labeled with a radioactive metal nuclide; a complex of the IgG-binding peptide with IgG; and a nuclear medical imaging diagnostic agent or a cancer diagnostic agent, etc., containing the IgG-binding peptide or the complex.

The invention involves viral vectors that can be used to tranduce a target cell, i.e. to introduce genetic material into the cell. The targets of interest are eukaryotic cells and particularly human cells. The transduction can be done in vivo or in vitro. More particularly the invention concerns viral vectors that have chimeric envelope proteins and contain the IgG-binding domain of protein A. These vectors when used in conjunction with antibodies targeting a particular cell are particularly useful for gene therapy.

It has been determined that allergens, which are characterized by both humoral (IgE) and cellular (T cell) binding sites, can be modified to be less allergenic by modifying the IgE binding sites. The IgE binding sites can be converted to non-IgE binding sites by masking the site with a compound that prevents IgE binding or by altering as little as a single amino acid within the protein, most typically a hydrophobic residue towards the center of the IgE-binding epitope, to eliminate IgE binding. The method allows the protein to be altered as minimally as possible, other than-within the IgE-binding sites, while retaining the ability of the protein to activate T cells, and, in some embodiments by not significantly altering or decreasing IgG binding capacity The examples use peanut allergens to demonstrate alteration of IgE binding sites. The critical amino acids within each of the IgE binding epitopes of the peanut protein that are important to immunoglobulin binding have been determined. Substitution of even a single amino acid within each of the epitopes led to loss of IgE binding. Although the epitopes shared no common amino acid sequence motif, the hydrophobic residues located in the center of the epitope appeared to be most critical to IgE binding.

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.

The present invention provides a peptide capable of specifically binding to human IgG. In particular, the present invention relates to a human IgG binding peptide tag of 11 to 16 amino acids in length, comprising at least an amino acid sequence of the formula I:C-(X)n-W-X-X-X-W-(X)m-C(I)(SEQ ID NO: 17)wherein n and m are each an integer of 1 or more and the sum n+m is 4 or 5, wherein X-X-X in the formula I contains no cysteine residue, andwherein said amino acid sequence satisfies either or both of a) and b):a) (X)n-W in the formula I denotes Za-G-Y-W (SEQ ID NO: 18); andb) W-(X)m in the formula I denotes W-G-L-Zb (SEQ ID NO: 19)wherein Za and Zb are each 0, 1, or more amino acid residues.

This invention relates to an IgG-binding peptide, an IgG-binding peptide modified with a cross-linking agent, a conjugate of the IgG-binding peptide modified with a cross-linking agent and IgG, and a method for producing the conjugate, etc.

The present invention relates to site-specific labeling of antibodies or fragments thereof with one or more reporter group(s) in a way that does not affect antigen binding. The method for labeling antibodies and / or fragments thereof, comprises the following steps a) providing an IgG binding protein, which comprises α-helix structures, with a photoactivatable group and at least one label; b) forming a mixture of said IgG binding protein and the antibodies and / or fragments to be labeled; and c) UV illuminating said mixture for site-specific labeling of said antibodies and / or fragments thereof. The IgG binding protein is preferably the Z domain of Protein A.

The invention discloses a class of small proteins and applications thereof. The backbone protein of the small protein is a mutant of the IgG-binding domain of Streptococcal protein G, and the small protein includes an alpha-helix and four beta-sheets, the alpha-helix running through a region surrounded by four beta-sheets , and at the same time, key amino acid sites capable of binding to PD-1 protein are also distributed on the β-sheet surface formed by the four β-sheets. The small protein of the present invention has a high structural similarity with PD‑L1 protein, can inhibit PD‑1 / PD‑L1 binding, and is a potential PD‑1 / PD‑L1 inhibitor, which has weak IgG binding ability and can be used in vivo The circulation residence time is long, and has high structural stability, can be used to inhibit the interaction between PD‑1 / PD‑L1, is simple to prepare, can be used for large-scale production and application, and facilitates the immunotherapy of cancer.

The present invention provides an IgG hybrid bispecific antibody against TNFα and IL-17A. The hybrid antibody comprises a first heavy chain and a first light chain from a human IgG binding specifically to TNFα, and a second heavy chain and a second light chain of a human IgG binding specifically to IL-17A. A variable region of the second heavy chain is exchanged with a variable region of the second light chain, and / or a variable region of the first heavy chain is exchanged with a variable region of the first light chain; and constant regions of the first heavy chain and the second heavy chain interact with each other via enhanced electrostatic interaction or hydrophobic interaction.

The invention relates to three IgG binding epitopes of a main soybean allergen Gly m Bd 28K. Amino acid sequences of the three IgG binding epitopes are 28H-Gly-Asp-Lys-Lys-Ser-Pro-Lys-Ser-Leu-Phe-Leu-Met-Ser-Asn-Ser-OH42, 56H-Leu-Lys-Ser-His-Gly-Gly-Arg-Ile-Phe-Tyr-Arg-His-Met-His-Ile-OH70 and 154H-Glu-Thr-Phe-Gln-Ser-Phe-Tyr-Ile-Gly-Gly-Gly-Ala-Asn-Ser-His-OH168 respectively. According to the IgG binding epitopes, suppression of the binding of a Gly m Bd 28K natural protein and a Gly m Bd 28K monoclonal antibody (mAb3F5) by the chemically synthesized polypeptide 56H-Leu-Lys-Ser-His-Gly-Gly-Arg-Ile-Phe-Tyr-Arg-His-Met-His-Ile-OH70 shows that the linear epitope polypeptide has a good suppression effect on affiliation of the Gly m Bd 28K natural protein and the Gly m Bd 28K monoclonal antibody (mAb3F5). The IgG binding epitopes are significant for proving a molecular mechanism produced by food allergy, understanding the effect of the allergen in food allergy, developing researches on non-allergic and hypoallergenic food and researching the occurrence of allergic diseases.