# A Specific Antibody for Detecting Human IgG4 in Medical Tests > This patent describes a unique lab-made antibody designed to precisely find and stick to a specific part of human IgG4, a type of immune protein, which is useful for diagnosing certain diseases. - **Patent:** US 20210140973 - **Original title:** Anti-human igg4 monoclonal antibody and human igg4 assay reagent using said antibody - **Owner:** Nitto Boseki Co - **Status:** Active - **Times cited:** 2 - **Field:** biotech, pharmaceutical, diagnostics, medical_devices ## What it does This patent claims a monoclonal antibody that specifically binds to human IgG4. The antibody targets a very particular spot, or epitope, on the human IgG4 heavy chain constant region (specifically amino acid positions 221 to 327 of SEQ ID NO: 4), which must include glutamic acid at position 299, as stated in claim 1. The patent also covers methods for using this antibody to detect human IgG4 in a sample, for example, through an immunological particle agglutination inhibition method (claim 11 and 12). This detection involves the antibody binding to IgG4 in the sample, then adding an insoluble carrier with IgG4 attached, and observing if clumping (agglutination) is inhibited, which indicates the presence of IgG4 in the original sample (claim 13). The patent further includes kits containing this antibody for such detection, which can assist in diagnosing IgG4-related diseases (claim 14 and 18). ## What it does NOT cover - Does not cover antibodies that bind to other types of human immunoglobulins like IgG1, IgG2, or IgG3. - Does not cover antibodies that bind to a different region or epitope on human IgG4, especially if it lacks glutamic acid at position 299. - Does not cover detection methods for human IgG4 that do not use this specific monoclonal antibody or its bivalent forms. - Does not cover detection methods that are not based on the principle of immunological particle agglutination inhibition. - Does not cover diagnostic methods for IgG4-related diseases that do not rely on detecting human IgG4 levels. ## The clever bit The cleverness lies in the extreme specificity of the monoclonal antibody. It's designed to bind to a very precise epitope on the human IgG4 heavy chain, specifically requiring glutamic acid at position 299. This targeted binding ensures that the antibody only detects IgG4, avoiding false positives from other similar proteins. ## Real-world examples 1. Diagnostic kits for IgG4-related autoimmune pancreatitis 2. Laboratory tests for IgG4-related sclerosing cholangitis 3. Assay reagents for measuring serum IgG4 levels in clinical settings 4. Research tools for studying IgG4-mediated immune responses ## Why it matters Human IgG4 is a specific type of antibody in the body, and its levels can be elevated in certain autoimmune conditions known as IgG4-related diseases. Accurately detecting and measuring IgG4 is crucial for diagnosing and monitoring these conditions. This patent provides a highly specific tool, a monoclonal antibody, that can improve the reliability and precision of such diagnostic tests, helping doctors identify these diseases more effectively. ## Frequently asked questions ### What does A Specific Antibody for Detecting Human IgG4 in Medical Tests cover? This patent describes a unique lab-made antibody designed to precisely find and stick to a specific part of human IgG4, a type of immune protein, which is useful for diagnosing certain diseases. ### Who owns patent US 20210140973? This patent is owned by Nitto Boseki Co. ### When does this patent expire? This patent is expected to expire on July 5, 2038, when the invention enters the public domain. ### What is patent US 20210140973 cited by? This patent has been cited by 2 later patents that build on its ideas. ### What problem does this patent solve? Human IgG4 is a specific type of antibody in the body, and its levels can be elevated in certain autoimmune conditions known as IgG4-related diseases. Accurately detecting and measuring IgG4 is crucial for diagnosing and monitoring these conditions. This patent provides a highly specific tool, a monoclonal antibody, that can improve the reliability and precision of such diagnostic tests, helping doctors identify these diseases more effectively. ### What does this patent NOT cover? Does not cover antibodies that bind to other types of human immunoglobulins like IgG1, IgG2, or IgG3. **Full plain-English explainer:** https://patentbrief.org/patent/us/20210140973/anti-human-igg4-monoclonal-antibody-and-human-igg4-assay-reagent-using-said-anti **Original patent:** https://patents.google.com/patent/US20210140973 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [An Antibody That Detects Specific Sugar-Protein Combinations for Diagnostics](https://patentbrief.org/patent/us/10479827/monoclonal-antibody-reacting-with-glycopeptide-and-use-thereof) — This patent describes a unique antibody designed to precisely recognize a specific sugar-protein structure, particularly a 'fucosylated glycopeptide' found on certain proteins like alpha-fetoprotein (AFP), which is useful for medical tests. - [Better Lab Tests with Engineered Humanized Antibodies](https://patentbrief.org/patent/us/20250102496/reagent-containing-humanized-antibody) — This patent describes a special lab test ingredient, a 'humanized antibody,' designed to make medical and research tests more accurate by preventing false alarms. - [How Two Special Antibodies Find Substances in Body Fluids](https://patentbrief.org/patent/us/4376110/psa-test-for-prostate-cancer) — This patent describes a "sandwich" method using two highly specific, man-made antibodies to detect and measure tiny amounts of specific substances, like disease markers, in a fluid sample. - [Detecting Bacteria Using Special Antibodies in Medical Tests](https://patentbrief.org/patent/us/20180164316/test-object-detection-method-and-immunoassay-instrument-and-monoclonal-antibody-) — This patent describes a way to test for certain bacteria, like Mycoplasma pneumoniae, by using a special antibody that can recognize two different parts of the bacteria at once. - [How to Find Antibodies That Only Detect Bound Drug Targets](https://patentbrief.org/patent/us/12590172/complex-specific-antibodies-and-antibody-fragments-and-its-use) — This patent describes a method to create and use special antibodies that only detect when a therapeutic or diagnostic antibody is bound to its target, ignoring both the target and the unbound antibody.