phagocyte

thumb|Scanning electron microscope|Scanning electron micrograph of a neutrophil phagocytosing anthrax bacilli (orange)|alt= Long rod-shaped bacteria, one of which has been partially engulfed by a larger blob-shaped white blood cell. The shape of the cell is distorted by undigested bacterium inside it.

Phagocytes are cells that protect the body by ingesting harmful foreign particles, bacteria, and dead or dying cells. They include monocytes, macrophages, neutrophils, tissue dendritic cells, and mast cells. Their name comes from the Greek '', "to eat" or "devour", and "-cyte", the suffix in biology denoting "cell", from the Greek kutos, "hollow vessel". They are essential for fighting infections and for subsequent immunity. Phagocytes are important throughout the animal kingdom and are highly developed within vertebrates. One litre of human blood contains about six billion phagocytes. They were discovered in 1882 by Ilya Ilyich Mechnikov while he was studying starfish larvae. Mechnikov was awarded the 1908 Nobel Prize in Physiology or Medicine for his discovery. Phagocytes occur in many species; some amoebae behave like macrophage phagocytes, which suggests that phagocytes appeared early in the evolution of life. Discovered in 2019, species of bacteria Candidatus'' Uabimicrobium amorphum can perform phagocytosis by eating other bacteria.