Palaniyar Nades, Nadesalingam Jeya, Reid Kenneth B M
MRC Immunochemistry Unit, Department of Biochemistry, Oxford University, Oxford OX1 3QU, UK.
Ann N Y Acad Sci. 2003 Dec;1010:467-70. doi: 10.1196/annals.1299.084.
Collectins are a class of innate immune proteins that opsonize microbes and other ligands via their carbohydrate-recognition domains and enhance their clearance by phagocytes. We hypothesized that collectins, such as pulmonary surfactant protein (SP-) A and D and mannose-binding lectin (MBL), could bind nucleic acid, which is a pentameric sugar-based anionic polymer. We have shown that SP-D and MBL bind to both DNA and RNA effectively and also that SP-D enhances the uptake of DNA by human monocytic cells. Therefore, our results suggest that nucleic acids may be a novel class of ligands for collectins. This class of innate immune proteins could enhance the clearance of DNA that is released by necrotic cells or microbial cells. Our findings may have important biological implications, such as the alleviation of DNA-mediated tissue inflammation.
凝集素是一类先天性免疫蛋白，它们通过其碳水化合物识别结构域调理微生物和其他配体，并增强吞噬细胞对它们的清除作用。我们推测，凝集素，如肺表面活性蛋白（SP-）A和D以及甘露糖结合凝集素（MBL），可能会结合核酸，核酸是一种基于五聚体糖的阴离子聚合物。我们已经表明，SP-D和MBL能有效结合DNA和RNA，并且SP-D还能增强人单核细胞对DNA的摄取。因此，我们的结果表明，核酸可能是凝集素的一类新型配体。这类先天性免疫蛋白可以增强对坏死细胞或微生物细胞释放的DNA的清除。我们的发现可能具有重要的生物学意义，比如减轻DNA介导的组织炎症。
