What cells produce antibodies?

• A. T cells
• B. Macrophages
• C. B cells
• D. Neutrophils

Answer: (C)

Antibodies are produced by B lymphocytes. When a B cell encounters its specific antigen, it can become activated—with help from helper T cells—then proliferate and differentiate into plasma cells. These plasma cells are the antibody factories, secreting large amounts of antibodies into the blood and other tissues. The antibodies bind to the antigen, neutralizing it or marking it for attack by other parts of the immune system. Other immune cells, like T cells, don’t make antibodies; they coordinate responses and can kill infected cells. Macrophages and neutrophils are phagocytes that ingest pathogens, but they don’t secrete antibodies.