The T-cell receptor (TCR) is a special molecule found on the surface of a type of immune cell called a T-cell. Think of T-cells like soldiers in your body’s defense system that help identify and attack foreign invaders like viruses and bacteria.
The TCR is like a sensor or antenna that allows T-cells to recognize specific targets, kind of like how a key fits into a lock. When the TCR encounters a target it recognizes, it sends signals to the T-cell telling it to attack and destroy the invader.