Dust cell

A dust cell (or alveolar macrophage) is a type of macrophage found in the pulmonary alveolus, near the pneumocytes, but separated from the wall.

Activity of the dust cells is relatively high, because they are located at one of the major boundaries between the body and the outside world.

Dust cells are another name for monocyte derivatives in the lungs that reside on respiratory surfaces and clean off particles such as dust or microorganisms.

Dust cells are frequently seen to contain granules of inorganic material such as carbon that they have picked up from respiratory surfaces. Such black granules may be especially common in smoker's lungs or long-term city dwellers.