Peptideantigens

Peptide antigens are small fragments of proteins that can trigger an immune response. When a larger protein, known as a native antigen, is broken down by cells, it can yield these smaller peptide pieces. These peptides can then be presented to immune cells, specifically T cells, by molecules called MHC (Major Histocompatibility Complex) proteins. This presentation is a crucial step in the adaptive immune system's ability to recognize and respond to foreign invaders or abnormal cells. The specific sequence of amino acids within a peptide determines its immunogenicity, meaning its ability to provoke an immune reaction. Even minor changes in the peptide sequence can significantly alter how it is recognized by T cells. Peptide antigens are vital in understanding immune tolerance, vaccine development, and the study of autoimmune diseases, where the immune system mistakenly attacks the body's own peptides. Researchers often synthesize specific peptide antigens to study immune cell behavior and to identify potential targets for therapeutic interventions.