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How do monoclonal antibodies differ from polyclonal antibodies?
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antibody
The four-chain structure of an antibody, or immunoglobulin, molecule. The basic unit is composed of two identical light (L) chains and two identical heavy (H) chains, which are held together by disulfide bonds to form a flexible Y shape. Each chain is composed of a variable (V) region and a constant (C) region.
The primary difference between monoclonal and polyclonal antibodies lies in their origin and specificity.
- Monoclonal antibodies are derived from a single clone of B cells and are identical immunoglobulin molecules. Because they originate from a single parent cell, they all recognize and bind to the exact same epitope on an antigen.21
- Polyclonal antibodies are produced during a natural immune response to an infection or immunization. This process involves many different B cells, each recognizing different epitopes on the same antigen. Consequently, the resulting blood serum contains a heterogeneous mixture of antibodies with varying binding affinities.2
While polyclonal antibodies are a natural product of the immune system, monoclonal antibodies are produced artificially—often using hybridoma technology or recombinant DNA techniques—to ensure high specificity and consistent supply for therapy, diagnostic testing, and research.21