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.
Source: National Human Genome Research Institute's Talking Glossary of Genetic Terms
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Lymphocyte
Source: National Human Genome Research Institute's Talking Glossary of Genetic Terms