Antigenic protein (generic)

Antigenic proteins are molecules, generally of high molecular weight and chemical complexity, recognized by the immune system as "non-self" and capable of stimulating the production of antibodies or the activation of lymphocytes[5][7]. They are typically proteins but may also include glycoproteins, lipoproteins, and other conjugated proteins. Examples include viral coat proteins, bacterial toxins, and tumor cell proteins. The immune system identifies and mounts responses against antigenic proteins by means of specific receptor molecules, with different epitopes (antigenic determinants) recognized by B-cell or T-cell receptors[5][7]. In medical applications, specific antigenic proteins are used as the basis for vaccines, diagnostics, and targeted therapies, but "antigenic protein" itself is not a precise term for any one biological molecule. Specification of the exact protein (e.g., "Hepatitis B surface antigen") is essential for scientific and clinical utility[5][7][9].

not applicable without a specific protein; mechanisms vary—immune modulation, neutralization, cytotoxicity, etc.[5]