Epitope (antigenic determinant)

An epitope (also called an antigenic determinant) is the specific region of an antigen that is recognized and bound by the variable regions of antibodies, B cell receptors, or T cell receptors[1][3][5][9][10]. Epitopes are usually composed of a short sequence of amino acids in proteins (5–15 residues) or a few sugar residues in polysaccharides, and can be classified as either linear (continuous amino acid sequences) or conformational (formed by protein folding bringing distant residues together)[3][5][10]. An antigen can contain multiple distinct epitopes, each recognized by different antibodies or immune cells. Epitopes play a central role in immune recognition, vaccine design, and the development of immunotherapies, but the term "antigen epitope" itself does not refer to a unique molecular target but rather a feature found within target antigens[1][3][5][7][9][10].

Other names

antigenic determinantepitope