Gabridge M G
Isr J Med Sci. 1984 Oct;20(10):920-3.
Model systems for the study of mycoplasma infections are available with various degrees of complexity. They offer the advantages of simplicity and control of environmental variables. More significantly, they have a homogeneity of cell type, which is necessary when analyzing the biochemical factors in pathogenicity. Cell cultures of fibroblasts are especially useful in studies of receptor sites. Human lung fibroblasts in monolayer format contain a sialoglycoprotein to which Mycoplasma pneumoniae attaches. Fibroblast membranes are extracted with lithium diiodosalicylate or Triton X-100 to provide a fraction rich in glycoprotein. Polyacrylamide gel electrophoresis revealed less than eight proteins, with the majority of the carbohydrate in a single zone. Autoradiography of gels from fibroblasts grown in radiolabeled medium revealed that this zone also had high concentrations of glucosamine. Detergent extracts competitively inhibited the attachment of M. pneumoniae to fibroblasts. Cultures of fibroblasts also have been used to show that M. pneumoniae disrupts de novo purine synthesis within hours after infection. Monolayers of ciliated respiratory epithelial cells displayed an even distribution of receptor sites over the cell membrane. Intact trachea perfusion cultures were used to establish the pattern of pathogen distribution in upper airways. These in vitro approaches provide valuable insight into the process of mycoplasma attachment and the subsequent metabolic alterations that cause cytotoxicity.
用于研究支原体感染的模型系统具有不同程度的复杂性。它们具有简单性和可控制环境变量的优点。更重要的是，它们具有细胞类型的同质性，这在分析致病性中的生化因素时是必要的。成纤维细胞的细胞培养物在受体位点的研究中特别有用。单层培养的人肺成纤维细胞含有肺炎支原体附着的唾液酸糖蛋白。用二碘水杨酸锂或 Triton X - 100 提取成纤维细胞膜以提供富含糖蛋白的部分。聚丙烯酰胺凝胶电泳显示少于八种蛋白质，大部分碳水化合物在单个区域。对在放射性标记培养基中生长的成纤维细胞的凝胶进行放射自显影显示该区域也含有高浓度的葡糖胺。去污剂提取物竞争性抑制肺炎支原体对成纤维细胞的附着。成纤维细胞培养物也已用于表明肺炎支原体在感染后数小时内破坏嘌呤的从头合成。单层纤毛呼吸道上皮细胞在细胞膜上显示出受体位点的均匀分布。完整的气管灌注培养物用于确定病原体在上呼吸道中的分布模式。这些体外方法为支原体附着过程以及随后导致细胞毒性的代谢改变提供了有价值的见解。
