Lymphocytes are a type of white blood cell that play a crucial role in the immune system and are found predominantly in the lymphatic system. They are a key component of the body's defense mechanism against infections, diseases, and foreign substances.
There are three main types of lymphocytes: T cells, B cells, and natural killer (NK) cells. T cells are responsible for cell-mediated immunity and can recognize and destroy infected or malignant cells. B cells, on the other hand, are involved in the production of antibodies, which are proteins that bind to specific antigens found on pathogens, neutralizing them and marking them for destruction. NK cells are responsible for identifying and eliminating cells that have been infected by viruses or have become cancerous.
Lymphocytes are produced in the bone marrow, and then mature in the thymus (in the case of T cells) or remain in the bone marrow (in the case of B cells). Once matured, lymphocytes circulate throughout the body via the bloodstream and lymphatic system, continuously surveying for any foreign substances or abnormal cells.
Imbalances or abnormalities in lymphocyte levels can indicate various medical conditions. For example, low levels of lymphocytes, known as lymphocytopenia, can be caused by certain viral infections, immunodeficiency disorders, chemotherapy, or other factors; whereas high levels, known as lymphocytosis, may be a sign of infection, inflammation, or certain types of leukemia.
