title: Host defense functions of pulmonary surfactant.
abstract: Surfactant is a complex of lipids and proteins that reduces surface tension at the air/liquid interface of the lung and regulates immune cell function. Surfactant immune function is primarily attributed to two proteins: SP-A and SP-D. SP-A and SP-D are members of a protein family known as 'collectins', which are distinguished by their N-terminal collagen-like region and their C-terminal lectin domain. The lectin domain binds preferentially to sugars on the surface of pathogens and thereby opsonizes them for uptake by phagocytes. The collectins also modulate the functions of cells of the adaptive immune network including dendritic cells and T lymphocytes. In addition, recent studies show that bacterial products degrade surfactant. In summary, surfactant plays an important role in lung host defense. Surfactant degradation or inactivation may contribute to enhanced susceptibility to lung inflammation and infection.
authors.affiliation: Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA. j.wright@cellbio.duke.edu
authors.forename: Jo Rae
authors.initials: JR
authors.lastname: Wright
mesh_terms: D006801:Humans; D007109:Immunity; D007239:Infections / Q000276:immunology; D007249:Inflammation / Q000276:immunology; D008168:Lung / Q000276:immunology; D008171:Lung Diseases / Q000378:metabolism; D037662:Pulmonary Surfactant-Associated Protein A / Q000502:physiology; D037663:Pulmonary Surfactant-Associated Protein D / Q000502:physiology; D037661:Pulmonary Surfactant-Associated Proteins / Q000032:analysis / Q000502:physiology*; D011663:Pulmonary Surfactants
chemical_list: D037662:Pulmonary Surfactant-Associated Protein A; D037663:Pulmonary Surfactant-Associated Protein D; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants