Pulmonary intravascular leukocyte sequestration. A potential mechanism of lung injury

Emphysema associated with alpha₁ antitrypsin deficiency may be a result of uninhibited action of proteolytic enzymes on lung tissues. The panacinar distribution and predilection for lower lung zones suggest that the injurious components may be distributed primarily through the pulmonary circulation. The observation that leukocyte lysosomes contain certain neutral proteases that are elastolytic emphasized these as a possible source of proteolytic enzymes. These studies demonstrate a model for repetitive pulmonary vascular leukocyte sequestration that may be associated with early widespread alveolar disruption.