Related Experiment Video
Updated: Sep 16, 2026

Characterization of Immune Cells and Proinflammatory Mediators in the Pulmonary Environment
Published on: June 24, 2020
The effects of pulmonary atelectasis and reexpansion on lung cellular immune defenses
Abstract:
Pulmonary atelectasis predisposes the lung to infection. This condition may be partly due to impaired cellular immune response of the collapsed lung segment. We postulated that atelectasis may affect alveolar macrophage (AM) antibacterial function. To test this hypothesis, atelectasis was induced in the right upper lobes of piglet lungs. Alveolar macrophages harvested by bronchoalveolar lavage of collapsed segments for up to 24 hours showed progressive depression of their phagocytic activity against Pseudomonas aeruginosa in vitro. However, their intracellular bactericidal activity did not change. Reexpansion of the atelectatic lobes with mechanical ventilation and 100% oxygen supplementation for four hours after six hours of atelectasis resulted in reversal of the impaired AM phagocytic activity. These observations presented insight into the mechanisms of susceptibility to lung infection in pulmonary atelectasis and the potential for its reversal.
Related Concept Videos
Pulmonary Cycle: Exhalation
Pneumonia II: Pathophysiology
Chronic Obstructive Pulmonary Disease-II: Pathophysiology
Chronic Inflammation
Atelectasis II: Pathophysiology
Chronic Obstructive Pulmonary Disease II: Emphysema
Chronic Obstructive Pulmonary Disease III: Chronic Bronchitis Features

