White blood cells (WBCs), also known as leukocytes, are a crucial component of the immune system in vertebrates, including humans. They play a significant role in protecting the body from infections, diseases, and foreign invaders. White blood cells are produced and primarily found in the bone marrow, lymph nodes, and spleen. There are several types of white blood cells, each with distinct functions and characteristics.
White blood cells function collectively to defend the body against infections and maintain its overall health. They can move through the bloodstream and migrate to the site of infection or inflammation by responding to chemical signals released by damaged tissues. White blood cells also play a role in immune memory, where the immune system “remembers” previous encounters with specific pathogens, leading to a faster and more effective response upon reexposure.
Abnormalities in white blood cell counts or function can indicate various health conditions, such as infections, autoimmune disorders, leukemia, and immune deficiencies. Medical professionals often analyze white blood cell counts as part of routine blood tests to assess a person’s immune system health and overall well-being.