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How do lymphocytes contribute to the immune response?
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white blood cell
Blood is made up of multiple components, including red blood cells, white blood cells, platelets, and water-rich plasma.
Lymphocytes are essential white blood cells that determine the specificity of the immune response to foreign substances, known as antigens. They originate in the bone marrow and are categorized into two primary types, T cells and B cells, which often act in concert to protect the body.12345
- B cells: These cells are responsible for humoral immunity. Upon encountering an antigen, they differentiate into plasma cells that secrete antibodies to bind to invaders circulating in body fluids.45
- T cells: These cells facilitate cell-mediated immunity. They monitor cell surfaces for foreign antigens and directly attack infected or abnormal cells. Subsets include helper T cells, which regulate the immune response by activating other cells, and cytotoxic T cells, which destroy infected cells.452
Through clonal selection, lymphocytes produce effector cells to fight active infections and memory cells that provide long-lasting immunity against future exposure to the same pathogen.6