epitooppeja
Epitooppeja are specific sites on an antigen that are recognized by the immune system, particularly by antibodies, T cells, and B cells. These sites are typically composed of a sequence of amino acids or sugar residues. When an antibody or a lymphocyte receptor binds to an epitooppi, it triggers an immune response. The term epitooppi originates from the Greek word 'epi' meaning 'upon' and 'topos' meaning 'place'. There are two main types of epitooppeja: conformational and linear. Conformational epitooppeja are formed by amino acids that are brought together in the three-dimensional structure of a protein, even if they are not adjacent in the linear sequence. These epitooppeja can be lost if the protein is denatured. Linear epitooppeja, on the other hand, are formed by a continuous sequence of amino acids in the polypeptide chain and are often preserved even after denaturation. The immune system's ability to recognize a vast array of epitooppeja is crucial for distinguishing between self and non-self, enabling the body to defend against pathogens. The study of epitooppeja is fundamental to immunology and has applications in vaccine development, diagnostics, and immunotherapy.