The Caplules of Staphylococcus aureus Clinical Isolates Work as the Colonization Factor

金黄色葡萄球菌包膜菌株在临床分离株中的比例很高。然而，金黄色葡萄球菌的荚膜多糖是否与其他细菌胶囊一样具有真正的致病作用尚不清楚。报道了11种被膜血清型，临床分离株多为5型或8型，临床分离株具有薄层被膜，被膜多糖不能覆盖胞壁磷壁酸。此外，高相对分子质量的疏水蛋白(200KD和160KD)强烈结合在胶囊表面，改变了胶囊的表面性质。我们分离纯化了其中一种疏水蛋白--200KD蛋白，命名为CP-PA。抗CP-PA的特异性抗体可分别与5型和8型标准血清型的雷诺株和贝克尔株反应，也可与多种临床分离株发生反应。从人血中分离到的疏水包膜菌株NM对PMN细胞和Vero细胞具有高度的粘附性。这些结果表明，金黄色葡萄球菌临床分离株的衣壳多糖对宿主细胞具有致病作用。

The rate of encapsulated strains of Stapylococcus aureus is very high among clinical isolates. However, it is still unclear that the capsular polysaccharide of S.aureus has the real pathogenic role as same as other bacterial capsules. Eleven serotypes of capsule are reported and most of clinical isolates belong to the serotype 5 or 8.We observed that the clinical isolates from human blood has the thin layered capsule and the capsular polysaccharide cannnot cover the cell wall teichoic acid. Furthermore, hydrophobic proteins of high molecular weight (200KD and l60KD) strongly bound to the surface of capsule and changed the surface characterisitcs to be hydrophobic. We isolated and purified 200KD protein, one of the hydrophobic proteins, and designated it as CP-PA.The specific antibody against CP-PA reacted on both strains Reynolds and Becker, standard serotype strains of type 5 and type 8 respectively, and it also reacted on many clinical isolated strains. The hydrophobic encapsulated strain NM isolated from human blood highly adhered to PMN cells and Vero cells. These results suggested that the capsular polysaccharide of S.aureus clinical isolates has the pathogenic role as colonization factor to the host cells.