Making Hybrid Antibodies from Different Animals

This patent describes how to create new, engineered antibodies by combining parts of antibodies from two different animal species, then growing them in a lab.

What it covers

This patent details a method for creating "chimeric immunoglobulins," which are special antibody parts made from genetic material of two different mammals. Specifically, it involves designing a DNA sequence where the "constant region" (the body of the antibody) matches one animal, and the "variable region" (the part that recognizes a target) matches a different animal (Claim 1a). This engineered DNA is then put into a "vector" (a delivery vehicle) and inserted into a "host cell" like bacteria or yeast (Claim 1b, 1c). These cells are grown in a lab, and they produce the desired chimeric antibody chains (Claim 1d, 1e). For example, a scientist could take the antigen-binding part of a mouse antibody that targets a specific cancer cell and combine it with the "body" part of a human antibody. This creates a new, hybrid antibody that can target the cancer but is less likely to be rejected by the human immune system.

What it doesn't cover

• —Does not cover antibodies made entirely from a single mammalian species.
• —Does not cover antibodies where the constant and variable regions come from the same mammalian species.
• —Does not cover methods of producing antibodies that do not involve recombinant cell culture.
• —Does not cover antibodies that are not "chimeric" in the sense of combining parts from different mammalian species.
• —Does not cover naturally occurring antibodies found in any single organism.

The clever bit

The key insight was realizing that you could mix and match the functional parts of antibodies from different species using recombinant DNA technology. This allowed researchers to harness the strong antigen-binding capabilities of animal antibodies while making the resulting therapeutic antibody more compatible with the human immune system.

Why it matters

This patent was foundational for developing "humanized" antibodies, which are critical in modern medicine. Before this, many therapeutic antibodies came from mice, and human bodies often rejected them. By allowing scientists to combine a mouse's target-finding ability with a human antibody's "body," it paved the way for drugs that are more effective and safer for patients. This technology enabled the creation of a new class of biologic drugs, particularly for treating cancers and autoimmune diseases.

Real-world examples

• 1.Rituximab (Rituxan) - a chimeric antibody for lymphoma
• 2.Infliximab (Remicade) - a chimeric antibody for autoimmune diseases
• 3.Many early therapeutic monoclonal antibodies
• 4.Antibody-drug conjugates (ADCs) that use chimeric frameworks