Pulmonary surfactant phospholipid monolayer (PS)

The pulmonary surfactant phospholipid monolayer is a critical thin film located at the air-liquid interface of the pulmonary alveoli (StatPearls, 2023). It is primarily composed of dipalmitoylphosphatidylcholine (DPPC) and other phospholipids, along with specific surfactant proteins (SP-A, B, C, and D) (PubMed, PMID: 25637150). Its fundamental biological role is to reduce surface tension within the lungs, which prevents alveolar collapse during expiration and significantly decreases the work required for breathing (NIH, 2022). A deficiency or dysfunction of this monolayer is the primary cause of Neonatal Respiratory Distress Syndrome (NRDS) and contributes to the pathophysiology of Acute Respiratory Distress Syndrome (ARDS) in adults (StatPearls, 2023). Therapeutic intervention typically involves the administration of exogenous surfactant preparations, which can be animal-derived or synthetic, to restore the mechanical stability of the alveoli (PubMed, PMID: 30051917). These drugs act by integrating into the endogenous lipid layer to lower surface tension and improve gas exchange (StatPearls, 2023). Monitoring surfactant health is often performed via amniotic fluid analysis or lamellar body counts in clinical settings (PubMed, PMID: 21422181).

Other names

Lung surfactantAlveolar surfactantPulmonary surfactant filmSurface-active agentPulmonary surfactant

Exogenous surfactant replacement therapy restores the surface-active properties of the alveolar lining by forming a stable phospholipid monolayer at the air-liquid interface, thereby reducing surface tension and preventing alveolar collapse (StatPearls, 2023; PubMed, PMID: 30051917).