Mucociliary escalator

Mucociliary escalator refers to the self-clearing mechanism of the bronchial tubes in the respiratory system. This mechanism involves the coordinated movement of cilia and the secretion of mucus to trap and transport foreign particles out of the body.

Function

The primary function of the mucociliary escalator is to protect the lungs from harmful substances. The cilia, which are tiny hair-like structures lining the bronchial tubes, beat in a coordinated fashion to move mucus and trapped particles upwards towards the throat. This mucus is then either coughed out or swallowed, effectively removing the foreign particles from the respiratory system.

Components

The mucociliary escalator consists of two main components: the cilia and the mucus.

Cilia

Cilia are microscopic, hair-like structures that line the bronchial tubes. They beat in a coordinated, wave-like motion to move mucus and trapped particles upwards towards the throat.

Mucus

Mucus is a sticky substance secreted by the goblet cells in the bronchial tubes. It serves to trap foreign particles, such as dust and bacteria, preventing them from reaching the lungs.

Clinical significance

Disruption of the mucociliary escalator can lead to respiratory diseases such as chronic bronchitis, cystic fibrosis, and primary ciliary dyskinesia. In these conditions, the movement of the cilia is impaired, leading to a buildup of mucus and trapped particles in the lungs. This can result in recurrent respiratory infections and damage to the lung tissue.

See also

• Respiratory system
• Cilia
• Mucus
• Goblet cell
• Chronic bronchitis
• Cystic fibrosis
• Primary ciliary dyskinesia