Surfactant protein D reduces alveolar macrophage apoptosis in vivo |
| |
Authors: | Clark Howard Palaniyar Nades Strong Peter Edmondson Jess Hawgood Samuel Reid Kenneth B M |
| |
Institution: | Medical Research Council Immunochemistry Unit, Department of Biochemistry, University of Oxford, Oxford, United Kingdom. howard.clark@bioch.ox.ac.uk |
| |
Abstract: | Surfactant protein D (SP-D) is a molecule of the innate immune system that recognizes the patterns of surface carbohydrate on pathogens and targets them for phagocytosis and killing. SP-D-deficient mice show an increased number of macrophages in the alveolar space, excess surfactant phospholipid, overproduction of reactive oxygen species, and the development of emphysema. We report here that SP-D-deficient mice have a 5- to 10-fold increase in the number of apoptotic and necrotic alveolar macrophages, as defined by annexin V and propidium iodine staining, respectively. Intrapulmonary administration of a truncated 60-kDa fragment of human recombinant SP-D reduces the number of apoptotic and necrotic alveolar macrophages and partially corrects the lipid accumulation in SP-D-deficient mice. The same SP-D fragment binds preferentially to apoptotic and necrotic alveolar macrophages in vitro, suggesting that SP-D contributes to immune homeostasis in the lung by recognizing and promoting removal of necrotic and apoptotic cells. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|