epitópot

Epitópot, commonly rendered in English as epitope, is the specific part of an antigen that is recognized by an antibody or by a T-cell receptor. The term derives from Greek, with epi meaning upon and topos meaning place. In immunology, epitopes can be linear (continuous) sequences of amino acids or conformational (discontinuous) regions formed by the three-dimensional folding of a protein.

B-cell epitopes are typically accessible on the surface of antigens and may be targeted by antibodies, whereas T-cell epitopes are short peptides presented by major histocompatibility complex (MHC) molecules and recognized by T-cell receptors. Epitopes can be dominant or subdominant in an immune response, and their recognition is influenced by antigen processing, MHC binding, and peptide stability.

Epitope identification and mapping are central to vaccine design and diagnostic development. Methods include peptide arrays, phage display, X-ray crystallography of antigen–antibody complexes, NMR spectroscopy, and computational epitope prediction. Epitope-based vaccines aim to include the essential antigenic determinants to elicit protective immunity while reducing nonessential or potentially harmful responses.

In diagnostics, epitope targeting can improve assay specificity by focusing on unique determinants. Epitope information also aids in understanding autoimmune cross-reactivity, tracking pathogen evolution, and monitoring immune escape. The concept is widely used across immunology, vaccinology, and molecular biology to study antigen–antibody interactions and to design targeted interventions.