Final answer:
Mast cells are the immune cells that release histamine, playing a key role in allergic reactions and the body's defense mechanisms.
Step-by-step explanation:
The cells that have the ability to release histamine are mast cells. Mast cells are a type of white blood cell, or leukocyte, that play a crucial role in the body's immune response. They are involved in allergic reactions and in the defense against pathogens. When activated, mast cells release histamine and other inflammatory molecules, which cause symptoms such as itching, sneezing, and increased mucus production. Histamines released by mast cells contribute to the dilation of nearby capillaries and recruit other immune cells like neutrophils and monocytes.
Macrophages, another type of immune cell, can both phagocytize pathogens and produce chemicals that promote inflammation, but they themselves do not release histamine.