CD3 complex

biochemistry

Also known as: CD3

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Last updated

July 16, 2026

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The CD3 complex, also known as CD3, is a group of molecules essential for T-cell activation. These molecules act as signal transducers, converting the binding of an antigen and receptor into internal cellular signals. The T-cell receptor is associated with the CD3 complex, which is crucial for T cells to recognize foreign proteins displayed on the surface of body cells. Without the CD3 complex, T cells cannot be activated, even if their receptors bind to an antigen. This complex plays a vital role in the immune system's ability to identify and respond to threats.1

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immune system
Function of the T-cell receptor
…group of molecules called the CD3 complex, or simply CD3, which is also necessary for T-cell activation. These molecules are agents that help transduce, or convert, the extracellular binding of the antigen and receptor into internal cellular signals; thus, they are called signal transducers. Similar signal transducing molecules are associated…
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…group of molecules called the CD3 complex, or simply CD3, which is also necessary for T-cell activation. These molecules are agents that help transduce, or convert, the extracellular binding of the antigen and receptor into internal cellular signals; thus, they are called signal transducers. Similar signal transducing molecules are associated…
Read More