What are the cells used by the immune system to fight infection commonly known as?

The cells used by the immune system to fight infection are commonly known as leucocytes, or white blood cells. These cells play a critical role in the body’s defense mechanisms against pathogens such as bacteria, viruses, and fungi. Leucocytes are involved in various immune responses, including recognizing and destroying foreign invaders, coordinating the immune response, and producing antibodies.

Other types of blood cells, such as platelets and red blood cells, serve different functions. Platelets are primarily involved in blood clotting, preventing blood loss from damaged vessels, while red blood cells are responsible for transporting oxygen throughout the body. Stem cells, on the other hand, are undifferentiated cells that can develop into various types of cells, including leucocytes, but they are not specifically involved in fighting infections themselves. Thus, leucocytes are the distinct group of cells that serve the direct function of combating infections in the immune system.