17 results about "Fab Fragments" patented technology

The invention is applicable to the technical field of C-reactive protein detection, and provides an anti-C-reactive protein monoclonal antibody idiotype antibody, a preparation method and application, and the anti-C-reactive protein monoclonal antibody idiotype antibody is secreted by a hybridoma cell strain; the hybridoma cell strain is a 7C4 hybridoma cell strain; the preparation method of the anti-C-reactive protein monoclonal antibody idiotype antibody comprises the following steps: S1, obtaining hybridoma cells: preparing an anti-C-reactive protein monoclonal antibody Fab fragment, then carrying out animal immunization, then carrying out cell fusion, and finally screening and cloning the hybridoma cells; and S2, preparing and screening an anti-C reactive protein monoclonal antibody idiotype antibody. The anti-C-reactive-protein monoclonal antibody idiotype antibody is used for replacing C-reactive protein to serve as a labeled antibody, the labeling process is simple, the labeling efficiency is high, and meanwhile the situation that a final product is affected due to instability of the C-reactive protein is avoided. Experimental results show that the detection method is good in specificity and wide in linear range.

The disclosure provides Fab fragments that are site-selectively conjugated to the surface of a lipid nanoparticle (LNP) through the natural interchain disulfide bond between the heavy chain and the light chain (i.e., the CL-CH1 disulfide bond) to make targeted LNPs (also referred to herein as conjugates). The targeted LNPs (conjugates) produced by the methods disclosed herein can transduce specific targeted cells. Hence, the targeted LNPs are capable of delivering therapeutic payloads to cells to treat disease in a subject.

Anti-SLAMF7 Fab fragments, antibodies, biparatopic antibodies, and chimeric antigen receptors (CARs) are provided herein. Also provided are polynucleotides encoded the anti-SLAMF7 Fab fragments, antibodies, biparatopic antibodies, and CARs. The anti-SLAMF7 Fab fragments, antibodies, biparatopic antibodies, and CARs are useful for the prevention and / or treatment of cancer, such as multiple myeloma. Also provided is a combination therapy including administration of the anti-SLAMF7 Fab fragments, antibodies, biparatopic antibodies, and CARs with an IL-16 or an IL-15 agonist.

The present invention provides bispecific antibodies of a new antibody format, and which comprise one or more Fab fragments and an immunoglobulin molecule. The invention further provides compositions of said bispecific antibodies, as well as methods and uses of the same. The invention further provides a method of generating bispecific antibodies of the new format.

The present invention belongs to the field of tumor immunotherapy, and relates to a humanized anti-VEGF antibody Fab fragment. The present invention discloses nucleic acid sequences (including heavy / light chain variable regions) encoding said antibody fragment, and vectors, pharmaceutical compositions and kits containing said nucleic acid sequences. The anti-VEGF antibody Fab fragments disclosed in the present invention can specifically bind to VEGF with high affinity and block the binding of VEGF to the receptor VEGFR2, and also neutralize the proliferative effect of VEGF on HUVEC cells. Compared to the full-length antibody, antibodies in the form of Fab fragments have stronger penetrability and less toxic in terms of gastrointestinal perforation, hypertension and hemorrhage and do not stimulate the complement cascade reaction, thus reducing the risk of endophthalmitis and autoimmune inflammatory reactions. Thus it could be used in clinical treatment of ocular diseases characterized by choroidal neovascularization, including but not limited to age-related macular degeneration (AMD), diabetic macular edema (DME), retinal edema, degenerative myopia, choroidal neovascularization (CNV).

Provided are a multispecific antigen-binding protein and a use thereof. Specifically provided is a bispecific or trispecific antigen-binding protein formed by linking scFv or Fab fragments derived from an anti-GPRC5D antibody, an anti-BCMA antibody, and an anti-CD3 antibody. The multispecific antigen-binding protein simultaneously targets two or three targets among GPRC5D, BCMA, and CD3, thereby improving the therapeutic effect against tumors; the present invention has application prospects in the anti-tumor field.

The invention relates to the technical field of antibody engineering, in particular to a molecular chaperone PDI for improving the effective display efficiency of Fab on the surface of yeast and application of the molecular chaperone PDI, and the molecular chaperone PDI comprises an amino acid sequence as shown in SEQ ID NO: 1. The effective display efficiency and stability of Fab can be remarkably improved through co-expression of the molecular chaperone and Fab, Fab fragments with high affinity or specificity can be efficiently screened out through flow cytometry (FACS), and an effective strategy is provided for accelerating discovery of high-performance antibodies.

This application relates to site-specific conjugation of antibody lysine residues using solid phase immobilized microbial transglutaminase MTG and MTG in solution. Site-specific modification of proteins using microbial transglutaminase (MTG) is a powerful and versatile strategy for controlled modification of proteins under physiological conditions. We present evidence that solid phase microbead immobilization can be used to site-specifically and efficiently link different functional molecules important for further downstream applications to therapeutically relevant proteins, including scFV, Fab fragments and antibodies. We demonstrate that MTG remains firmly immobilized and there is no detectable column bleed and the enzyme activity is maintained during continuous operation, which allows for convenient recycling of the enzyme, thus outperforming solution phase MTG conjugation. Furthermore, it is shown that immobilized MTG exhibits an enhanced selectivity for certain residues in the presence of several reactive residues, all of which are targeted if conjugation is performed in solution. Site-specific lysine conjugation of antibodies using immobilized and solution MTG with a highly efficient glutamine-containing peptide is also reported. In addition, the generation of bis-site-specific conjugated IgGl with site-specific conjugation of both glutamine and lysine residues of an IgGl antibody using immobilized and solution MTG is reported. Site-specific glutamine conjugation with small peptides containing lysine residues and functional moieties is also described.

The present invention relates to multispecific antibody constructs comprising Fab fragments having a specific set of mutations at the interface of the CH1 and CL domains, said mutations preventing heavy / light chain mismatch.

The invention relates to multispecific antibody constructs comprising Fab fragments having mutations at the interface of the CHI and CL domains, said mutations preventing heavy chain / light chain mispairing.

A method is provided for determining the relative unpaired glycan content of an IgG antibody composition. In an exemplary embodiment, the method comprises (b) treating the IgG antibody composition with two enzymes to form a mixture of Fab fragments and Fc fragments, wherein one enzyme cleaves the antibody heavy chain at the N-terminal site of the hinge region disulfide bond and the other enzyme cleaves the β1,4 bond between core GlcNAc residues to form Fc fragments, each containing a pair of coreglycan structures; (b) separating the Fab fragments from the Fc fragments; and (c) quantifying the abundance of (i) paired non-fucosylated Fc fragments, (ii) unpaired non-fucosylated Fc fragments, (iii) paired high-mannose Fc fragments, and / or (iv) unpaired high-mannose Fc fragments to determine the relative unpaired non-fucosylated (AF) glycan content and the relative unpaired high-mannose (HM) glycan content.

The present invention belongs to the technical field of biochemical detection, and specifically relates to a kit and application for multiple immunoassays. It can be used for multi-target detection of circulating tumor cells in different body fluids such as blood, or for projects involving multi-target detection in tissue sections, cell slides and other detection processes. It is particularly suitable for multi-target staining experiments of antibodies of the same species but different subtypes. By digesting the anti-mouse IgG antibodies obtained by goat immunization with papain, purifying the Fab fragments and labeling them with dyes, a GM Fab secondary antibody with subtype recognition ability is prepared, which is used for specific blocking operations after multiple rounds of primary antibody staining, significantly reducing cross-interference between different primary antibodies. After multiple staining verification in tumor tissues and circulating tumor cells after blood enrichment, the results show that the signal distribution of each target is clear, the positioning is accurate, and the background interference is low, which is suitable for tumor immune microenvironment analysis and immunotherapy evaluation.

The invention relates to a preparation method of a test strip for detecting tetrodotoxin based on a magnetic fluorescence signal probe and a Fab-tetrodotoxin-aptamer sandwich method. The preparation method comprises the following steps: preparing streptavidin magnetic beads with fluorescence signals through an amide reaction; the preparation method comprises the following steps: shearing an anti-tetrodotoxin monoclonal antibody stored in a laboratory by using papain to obtain a Fab fragment, biotinylating the Fab fragment, and then coupling the biotinylated Fab fragment with streptavidin magnetic beads with fluorescence signals through high affinity between biotin and streptavidin to obtain the magnetic fluorescence signal probe. The prepared signal probe has three functions: a matrix is separated and toxin is enriched through magnetic separation, the magnetic beads simultaneously generate a colorimetric signal and a fluorescence signal, and a biotin-streptavidin system amplifies a detection signal. In addition, the structure of the existing aptamer is optimized, and the obtained truncated aptamer is used for forming a detection line of the test strip. Tetrodotoxin is detected by using an antibody-toxin-aptamer sandwich method principle, so that non-specific binding can be effectively reduced, the anti-interference capability is improved, rapid qualitative and quantitative detection of a sample can be realized, and the kit has a good application prospect.

The disclosure provides Fab fragments that are site-selectively conjugated to the surface of a lipid nanoparticle (LNP) through the natural interchain disulfide bond between the heavy chain and the light chain (i.e., the CL-CH1 disulfide bond) to make targeted LNPs (also referred to herein as conjugates). The targeted LNPs (conjugates) produced by the methods disclosed herein can transduce specific targeted cells. Hence, the targeted LNPs are capable of delivering therapeutic payloads to cells to treat disease in a subject.

The present invention provides bispecific antibodies of an antibody format, and which comprise one or more Fab fragments and an immunoglobulin molecule. The invention further provides compositions of said bispecific antibodies, as well as methods and uses of the same. The invention further provides a method of generating bispecific antibodies of the format.

Anti-SLAMF7 Fab fragments, antibodies, biparatopic antibodies, and chimeric antigen receptors (CARs) are provided herein. Also provided are polynucleotides encoded the anti-SLAMF7 Fab fragments, antibodies, biparatopic antibodies, and CARs. The anti-SLAMF7 Fab fragments, antibodies, biparatopic antibodies, and CARs are useful for the prevention and / or treatment of cancer, such as multiple myeloma. Also provided is a combination therapy including administration of the anti-SLAMF7 Fab fragments, antibodies, biparatopic antibodies, and CARs with an IL-16 or an IL-15 agonist.