Frampton H K, Freer J H, Birkbeck T H, Wardlaw A C
Department of Microbiology, University of Glasgow.
J Med Microbiol. 1991 Jan;34(1):45-50. doi: 10.1099/00222615-34-1-45.
An assay has been developed for Bordetella pertussis heat-labile toxin (HLT) based on morphological alterations in certain human embryonic lung (HEL) cell lines. Eighteen cell lines from human and other sources were tested but only two, MRC-5 and HELu2, were responsive to HLT. Confluent monolayers of the cells contracted within 24 h of exposure to the toxin, but without loss of viability during incubation for a further 3 days. The effect of HLT was quantitated by scoring the extent of morphological change, and by the decrease in Giemsa staining of the cell monolayers, as measured on an ELISA plate reader. This cell culture assay for HLT was more sensitive than lethality titration in mice but the dose-response curve had a lower slope. The specificity of the response was established by comparing unheated HLT with HLT heated at 56 degrees C, and with extracts from transposon-insertion mutants of B. pertussis which were deficient in HLT. Purified preparations of pertussis toxin and B. pertussis lipopolysaccharide gave no morphological response even at high doses.
已开发出一种基于某些人胚肺（HEL）细胞系形态学改变的百日咳博德特氏菌不耐热毒素（HLT）检测方法。对来自人和其他来源的18种细胞系进行了检测，但只有两种，即MRC - 5和HELu2，对HLT有反应。细胞的汇合单层在接触毒素后24小时内收缩，但在进一步培养3天期间没有活力丧失。通过对形态变化程度进行评分以及通过在酶联免疫吸附测定（ELISA）酶标仪上测量细胞单层吉姆萨染色的减少来定量HLT的作用。这种用于HLT的细胞培养检测方法比小鼠致死率滴定更敏感，但剂量反应曲线的斜率较低。通过比较未加热的HLT与在56℃加热的HLT以及来自缺乏HLT的百日咳博德特氏菌转座子插入突变体的提取物，确定了反应的特异性。纯化的百日咳毒素制剂和百日咳博德特氏菌脂多糖即使在高剂量下也没有形态学反应。
