Institute of Molecular Genetics of the Czech Academy of Sciences
We consider T cells as the most fascinating cells in our bodies. Unlike the vast majority of other somatic cells, each T cell is genetically unique, because it shuffles the pieces of DNA that encode its antigenic receptor. It means that each single T cell has its unique antigenic receptor with a unique specificity. We can compare the T cells to an army of soldiers, each of them carrying a unique weapon used in a specific situation. When the organism is infected with a pathogen, there are always a couple of T cells with the right weapon/receptor that initiate the adaptive immune response. On the other hand, too much of T-cell reactivity might induce friendly fire, or autoimmunity in immunological terms.
