http://www.ck12.org Chapter 1. Human Biology
1.63 B and T Cell Response
- Explain how B cells and T cells respond to pathogens.
What happens when your body recognizes an invader?
When your immune system detects an invading pathogen, it goes on the attack! Notice how this T-cell is setting out
to destroy a cancer cell.
B and T Cell Response
Some defenses, like your skin and mucous membranes, are not designed to ward off a specific pathogen. They are
just general defenders against disease. Your body also has defenses that are more specialized. Through the help of
your immune system, your body can generate an army of cells to kill that one specific pathogen.
There are two different types of specific immune responses. One type involves B cells. The other type involves T
cells. Recall thatB cellsandT cellsare types of white blood cells that are key in the immune response.
B Cell Response
B cells respond to pathogens and other cells from outside the body in the blood and lymph.
Most B cells fight infections by making antibodies. Anantibodyis a large, Y-shaped protein that binds to anantigen,
a protein that is recognized as foreign. Each antibody can bind with just one specific type of antigen (Figure1.125).
They fit together like a lock and key. Once an antigen and antibody bind together, they signal for aphagocyteto
destroy them.