A monoclonal antibody is an antibody derived from a single clone of B cells that recognizes one specific epitope on an antigen. Unlike polyclonal antibodies, all molecules in a monoclonal preparation are identical and bind to the same target.
Production and Applications
Monoclonal antibodies are created by isolating a B lymphocyte producing the desired antibody and fusing it with an immortal myeloma cell to form a hybridoma. This hybridoma cell line can be cultured to produce large amounts of a single antibody with consistent specificity. Advances such as recombinant expression systems and humanization techniques have improved their safety and reduced immunogenicity.
These antibodies have become key tools in medicine and research. In diagnostics, monoclonal antibodies form the basis of many immunoassays, including rapid antigen tests for infectious diseases and enzyme‑linked immunosorbent assays. In therapeutics, they are used to block cytokines, deplete specific cell populations, or deliver cytotoxic drugs. Examples include antibodies targeting CD20 on B cells for lymphomas, HER2 in breast cancer, and TNFα in inflammatory disorders. Because each antibody binds a single epitope, they provide targeted interference with fewer off‑target effects than broad immunosuppressive agents.
Clinical and Laboratory Examples
Therapeutic monoclonal antibodies span oncology, autoimmune disease and infectious disease. Rituximab depletes CD20‑positive B cells in non‑Hodgkin lymphoma. Trastuzumab targets HER2 and improves outcomes in HER2‑positive breast cancers. Adalimumab and infliximab neutralize TNFα and reduce inflammation in rheumatoid arthritis and Crohn disease. Diagnostic uses include pregnancy tests that detect human chorionic gonadotropin and lateral flow assays for pathogens such as SARS‑CoV‑2. In research, monoclonal antibodies serve as precise reagents to detect or purify proteins.
Monoclonal antibodies provide highly specific binding to a single epitope, enabling reliable detection and targeted therapy. Their production by hybridoma or recombinant methods ensures uniformity and reproducibility. These features underpin their wide utility in research, diagnostics and treatment across many fields.
Related Terms: Polyclonal Antibody, Hybridoma, Epitope, B Cell, Therapeutic Antibody