Wednesday, October 7, 2009

Leukocytes are the white blood cells of the blood tissue and the immune system, which protects the body against both infectious diseases and foreign materials by identifying, killing, and fagocytizing bacteria, fungi, and viruses. There are five different types of leukocytes: 1) neutrophils, which protect us against bacterial and fungal infection; 2) basophils, which are responsible for allergic and antigen response, releasing the chemical histamine causing inflammation; 3) eosinophils, which defend against parasitic infection; 4) monocytes, which divide and differentiate into macrophages to carry out the job of cleaning and phagocytizing bacteria, viruses and debris ; 5) Lymphocytes, which perform the most complex function of the immune system: recognize, identify, signaling, and destroy bacteria and viruses. All leukocytes are produced and derived from a multipotent cell in the bone marrow known as a hematopoietic stem cell. Leukocytes are found throughout the body, specially in the blood and lymphatic system.