McNeely T B, Coonrod J D
Department of Medicine, VA, Lexington, KY.
J Infect Dis. 1993 Jan;167(1):91-7. doi: 10.1093/infdis/167.1.91.
Surfactant protein A (SP-A) is a glycosylated apoprotein that may facilitate bacterial phagocytosis and contribute to early bacterial clearance in the lung. The effect of SP-A on attachment (or ingestion) of Staphylococcus aureus and type 25 pneumococci to rabbit alveolar macrophages and human monocyte-derived macrophages was studied. SP-A bound to S. aureus and type 25 pneumococci in a calcium-dependent manner. Bacteria-associated SP-A significantly increased attachment of S. aureus, but not pneumococci, to macrophages. Increased association of SP-A-coated S. aureus with macrophages appeared to consist mainly of attachment without ingestion, as determined by bactericidal tests and release of tritiated bacterial digestion products from macrophages. Preincubation of macrophages with SP-A did not increase attachment or ingestion of S. aureus or type 25 pneumococci, with or without the addition of immune opsonins. SP-A acts as a ligand to facilitate attachment of S. aureus to macrophages but has no effect on S. pneumoniae.
表面活性蛋白A（SP-A）是一种糖基化载脂蛋白，可能有助于细菌吞噬作用，并在肺部细菌的早期清除中发挥作用。研究了SP-A对金黄色葡萄球菌和25型肺炎球菌黏附（或摄取）兔肺泡巨噬细胞和人单核细胞衍生巨噬细胞的影响。SP-A以钙依赖的方式与金黄色葡萄球菌和25型肺炎球菌结合。与细菌结合的SP-A显著增加了金黄色葡萄球菌对巨噬细胞的黏附，但对肺炎球菌没有作用。通过杀菌试验和巨噬细胞中氚标记细菌消化产物的释放确定，包被SP-A的金黄色葡萄球菌与巨噬细胞的结合增加似乎主要是黏附而非摄取。无论是否添加免疫调理素，巨噬细胞与SP-A预孵育均不会增加金黄色葡萄球菌或25型肺炎球菌的黏附或摄取。SP-A作为一种配体，有助于金黄色葡萄球菌黏附于巨噬细胞，但对肺炎链球菌没有影响。
