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​Lymphocyte

updated: December 10, 2024

Definition

A lymphocyte is a type of white blood cell that is part of the immune system. There are two main types of lymphocytes: B cells and T cells. The B cells produce antibodies that are used to attack invading bacteria, viruses, and toxins. The T cells destroy the body's own cells that have themselves been taken over by viruses or become cancerous.

 lymphocyte


Narration

Lymphocytes are cells that circulate in your blood that are part of the immune system. There are two main types lymphocytes: T cells and B cells. B cells produce antibody molecules that can latch on and destroy invading viruses or bacteria. T cells are direct fighters of foreign invaders and also produced cytokines, which are biological substances that help activate other parts of the immune system. One such part is called macrophages. These macrophages act to clean up the invaders and the dead tissue after an immune response.