Morath Siegfried, Geyer Armin, Spreitzer Ingo, Hermann Corinna, Hartung Thomas
University of Konstanz, Biochemical Pharmacology, Konstanz, Germany.
Infect Immun. 2002 Feb;70(2):938-44. doi: 10.1128/IAI.70.2.938-944.2002.
Fractionation of commercial preparations of lipoteichoic acids (LTA) by hydrophobic interaction chromatography (HIC) and nuclear magnetic resonance spectroscopy revealed very inhomogeneous compositions and decomposition of the LTA structure: LTA content of the preparations averaged 61% for Streptococcus pyogenes, 16% for Bacillus subtilis, and 75% for Staphylococcus aureus. The decomposition was characterized by a loss of glycerophosphate units as well as alanine and N-acetylglucosamine substituents. All preparations contained-to varying degrees-non-LTA, non-lipopolysaccharide (LPS) immunostimulatory components as indicated by their elution profile in HIC, lack of phosphate, and negative Limulus amoebocyte lysate (LAL) test results. After purification, the commercial LTA from Bacillus subtilis and S. pyogenes but not LTA from S. aureus induced the release of tumor necrosis factor alpha, interleukin 1 beta (IL-1beta), IL-6, and IL-10 in human blood. While pure LTA are negative in the LAL assay, endotoxin equivalents of more than 10 ng of LPS/mg of LTA were found in the commercial preparations. Taken together, these data indicate that these crude preparations with relatively high endotoxin contamination are not suitable for characterizing the activation of immune cells by LTA.
通过疏水相互作用色谱法（HIC）和核磁共振光谱法对脂磷壁酸（LTA）商业制剂进行分级分离，结果显示LTA的组成非常不均一且结构分解：化脓性链球菌制剂的LTA含量平均为61%，枯草芽孢杆菌为16%，金黄色葡萄球菌为75%。这种分解的特征是甘油磷酸单元以及丙氨酸和N-乙酰葡糖胺取代基的丢失。所有制剂都不同程度地含有非LTA、非脂多糖（LPS）免疫刺激成分，这从它们在HIC中的洗脱图谱、缺乏磷酸盐以及鲎试剂（LAL）检测结果呈阴性可以看出。纯化后，来自枯草芽孢杆菌和化脓性链球菌的商业LTA能诱导人血中肿瘤坏死因子α、白细胞介素1β（IL-1β）、IL-6和IL-10的释放，但金黄色葡萄球菌的LTA则不能。虽然纯LTA在LAL检测中呈阴性，但在商业制剂中发现内毒素当量超过10 ng LPS/mg LTA。综上所述，这些数据表明这些内毒素污染相对较高的粗制制剂不适合用于表征LTA对免疫细胞的激活作用。
