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.

What it covers

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 doesn't 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.

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.

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