Lymphocytes The White Blood Cells.
As the name suggests lymphocytes are white blood cells and are found in lymph nodes and thymus. Lymphocyte produced by lymphoid proginator cells which arises from heamopoetic stem cells in the bone marrow. Process of lymphocyte production in bone marrow is termed lymphopoiesis. From bone marrow lymphocyte find their way to the circulatory system, lymphatic circulatory system. T Lymphocytes cells are located in Thymus. While B-Lymphocytes cells are found in lymphatic systems like lymph nodes. B-Lymphocytic cells are released from bone marrow when they are fully grown. Where as T-Lymphocyte cells migrate from bone marrow to thymus where they station there and grow further.
Different types of Lymphocyte and their role in providing immunity.
There are three types of lymphocyte.
1) T-Cells. 2) B cells 3) Natural Killer cells.
T lymphocytes:
T-Cell Lymphocytes are responsible for identification of antigen, differentiation between own, self body tissue cells and pathogen cells. T-Lymphocytic cells Identity virus infected cells of our body and initiate release of cytokine for activation of immune response by B cells.
B-lymphocytes:
B- lymphocytes are responsible for production of antibodies against pathogens, virus, and tumor cells. B-Cells Lymphocyte produce antibodies against pathogens. Antibodies react with antigens and form an antigen antibody complex and neutralize the pathogen (antigen) and foreign protein allergens. Lymphocyte B cells are responsible for developing memory of past infection, and respond to subsequent infection fromn same microoganism when it trys to invade our body second time. Therefore, they are also termed as Memory B Cells.
Memory Cells the B Lymphocytes are the base of the working of vaccines against any kind of infection.
Natural Killer Cells Lymphocytes:
Natural killer cells protect our body from the virus infected body cells, as they hold the biggest load of pathogens these cells are destroyed by natural killer cells. Natural killer cells guide Macrophages phagocytosis and T Lymphocyte triggering immune response.
Monocytes:
Monocytes are largest white blood cells; they are lymphocytes; they are produced in bone marrow from monoblasts cells which are produced by hematopoietic stem cells in the bone marrow.
Monocytes are mononuclear agranulocytes, which can further differentiate and give rise to macrophages and dendritic cells.
Monocytes are phagocytic cells which take part in phagocytosis and eliminate pathogenic microorganisms. Monocytes migrate at the point of tissue injury and trigger activation of T-Lymphocytes with production of cytokine. Monocytes produce Monocyte dendritic cells which take part in antigen presentation to B-Cell activation and activation of production of antibodies against the pathogen.
Thrombocytes:
Thrombocytes are also called platelets. Platelets play a very important role in the process of inflammation and tissue repair and the process of coagulation and formation of blood clot.
Platelets are of irregular shape, and do not contain nuclease. They aggregate at the site of injury and form a plug of platelets with the help of fibrin fibers. Platelets are produced in bone marrow by stem cells.