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Development of a Neonatal Piglet Acute Lung Injury Model Recreating the Early Environment of Preterm Infant Lungs
Published on: October 31, 2025
Surfactant proteins in innate host defense of the lung
1Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039, USA. jeff.whitsett@cchmc.org
Abstract:
Surfactant proteins A and D (SP-A and SP-D) are members of the collectin family of host defense proteins that are expressed in epithelial cells lining the lung. SP-A and SP-D interact with surfactant lipids in complex ways to determine the structure of tubular myelin, and the ratio of surfactant subfractions that, in turn, influences surfactant uptake and metabolism, respectively. SP-A and SP-D play critical roles in host defense of the lung against diverse viral, fungal, and bacterial pathogens. The collectins bind to the surfaces of microbes via carbohydrate-dependent interaction, aggregating, opsonizing, and enhancing clearance of the organisms by alveolar macrophages in the lung. Pulmonary surfactant proteins A and D play dual roles in pulmonary homeostasis, determining the structure of alveolar lipids and mediating the innate host defense system of the lung.
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