Macrophages

• Macrophages circulate the blood as monocytes. When an infection is found, the cell is activated and is referred as a macrophage. A macrophage destroys invading cells through a process called phagocytosis. Phagocytosis is a process in which the cell ingests the microbe and destroys it with internal organelles called lysozymes. The macrophage then presents the antigens from the microbe and its surface, and is destroyed by T cells.
  
  

T Cells

• There are two types of T cells: cytotoxic and helper. T helper cells connect to antigens that invade the tissue and produce chemicals that activate cytotoxic T cells. Cytotoxic T cells are a part of the cell mediated immunity, which destroys cells when they are found in the body. Cytotoxic T cells are also responsible for destroying tumor or virally infected cells. T helper cells work with macrophages by attaching to the cell and creating cytokines that bring other cells to the area of infection.
  
  

Neutrophils

• Neutrophils are one of the most abundant immune cells in the body. They are also one of the first defense mechanisms in the body. Neutorophils are a part of the body's inflammation response. They also move to the site of infection through a process called chemotaxis. Chemotaxis is an effect where cells move toward a specific location based on chemical signals that emanate from the area of infection.
  
  

Eosinophils

• Eosinophils like neutrophils are a part of the granulocyte group of leukocytes. These cells comprise a very small part of the circulating white blood cells in they body, but they also are a part of inflammation that is responsible for diseases like asthma and allergic reactions. Eosinophils also play a large role in fighting off viral infections since they carry enzymes that degrade the RNA structure in viral microbes.
  
  

Basophils

• Basophils are the least prominent cells that circulate in the bloodstream. These cells are also a part of the inflammation response from the immune system. They also produce an anticoagulant factor called heparin. Additionally, the cells produce histamine, which is responsible for the vasodilation of the infected area and causes edema. The edema is a part of the immune system that allows other cells to enter the area of infection.