clonal selection theory

immunology

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July 16, 2026

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The clonal selection theory is a fundamental concept in immunology that explains how the immune system develops specific responses to foreign substances, known as antigens.123

The theory posits that each individual lymphocyte is capable of recognizing a specific antigen. When a lymphocyte encounters its matching antigen, it becomes activated and multiplies, creating a clone of identical cells. These clones are then differentiated into effector cells, which fight the current infection, and memory cells, which provide long-lasting immunity against that specific antigen. This process is crucial for acquired immunity, allowing the body to remember and more effectively combat pathogens it has encountered before.123

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immune system
Activation of T and B lymphocytes
The process, called clonal selection, is one of the fundamental concepts of immunology.
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The process, called clonal selection, is one of the fundamental concepts of immunology.
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Niels K. Jerne
…basis for Frank Macfarlane Burnet’s clonal selection theory of 1957. Jerne’s second theory, put forth in 1971, postulates that the body learns in the thymus to distinguish between its own components and those that are foreign. The third, and perhaps most famous, of Jerne’s theories is the network theory, which…
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…basis for Frank Macfarlane Burnet’s clonal selection theory of 1957. Jerne’s second theory, put forth in 1971, postulates that the body learns in the thymus to distinguish between its own components and those that are foreign. The third, and perhaps most famous, of Jerne’s theories is the network theory, which…
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Sir Macfarlane Burnet
…developed a model, called the clonal selection theory of antibody formation, that explains how the body is able to recognize and respond to a virtually limitless number of foreign antigens. The theory states that an antigen entering the body does not induce the formation of an antibody specific to itself—as…
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…developed a model, called the clonal selection theory of antibody formation, that explains how the body is able to recognize and respond to a virtually limitless number of foreign antigens. The theory states that an antigen entering the body does not induce the formation of an antibody specific to itself—as…
Read More