Adaptive Immunity
Save
Adaptive immunity is a complex and fascinating system that protects the body from infection. It is a type of immune response that is tailored to specific pathogens, and it is essential for long-term protection against disease.
How does adaptive immunity work?
Adaptive immunity is mediated by a type of white blood cell called a lymphocyte. Lymphocytes are produced in the bone marrow and then travel to different parts of the body, where they circulate in the blood and lymph. When a lymphocyte encounters a foreign antigen, it becomes activated and begins to divide. This process, called clonal expansion, results in the production of a large number of identical lymphocytes, each of which is specific for the antigen that triggered its activation.
Types of adaptive immunity
There are two main types of adaptive immunity: humoral immunity and cell-mediated immunity.
Humoral immunity
Humoral immunity is mediated by antibodies, which are proteins that bind to specific antigens and neutralize them. Antibodies are produced by B cells, which are a type of lymphocyte. When a B cell encounters an antigen, it becomes activated and begins to divide. This process, called clonal expansion, results in the production of a large number of identical B cells, each of which is specific for the antigen that triggered its activation.
Cell-mediated immunity
Cell-mediated immunity is mediated by T cells, which are a type of lymphocyte. T cells kill infected cells and help to activate other immune cells. When a T cell encounters an antigen, it becomes activated and begins to divide. This process, called clonal expansion, results in the production of a large number of identical T cells, each of which is specific for the antigen that triggered its activation.
