SomaLogic, Inc., 2945 Wilderness Place, Boulder, CO 80301, USA.
Diagn Microbiol Infect Dis. 2013 Jul;76(3):278-85. doi: 10.1016/j.diagmicrobio.2013.03.029. Epub 2013 May 13.
Rapid and accurate diagnostic tests for Clostridium difficile infections (CDI) are crucial for management of patients with suspected CDI and for infection control. Enzyme immunoassays for detection of the toxins are routinely used but lack adequate sensitivity. We generated slow off-rate modified aptamers (SOMAmer™ reagents) via in vitro selection (SELEX) that bind toxins A, B and binary toxin with high affinity and specificity. Using SOMAmers alone or in conjunction with antibodies, we have developed toxin assays with a 1 pmol/L (300 pg/mL) limit of detection and a 3 log dynamic range. SOMAmers proved useful as capture or detection agents in equilibrium solution binding radioassays, pull-down capture assays, dot blots, and plate- or membrane-based sandwich assays, thus represent a promising alternative to antibodies in diagnostic applications. SOMAmers detected toxins A, B and binary toxin in culture supernatants from toxigenic C. difficile, including a BI/NAP1 strain and historic strains.
快速准确的艰难梭菌感染（CDI）诊断检测对于疑似 CDI 患者的管理和感染控制至关重要。用于检测毒素的酶免疫分析通常被使用，但缺乏足够的灵敏度。我们通过体外选择（SELEX）生成了缓慢解离修饰的适体（SOMAmer™试剂），它们与毒素 A、B 和二元毒素具有高亲和力和特异性。我们单独使用 SOMAmer 或与抗体一起开发了毒素检测试剂盒，检测限为 1 pmol/L（300 pg/mL），动态范围为 3 个对数级。SOMAmer 在平衡溶液结合放射分析、下拉捕获分析、斑点印迹和基于平板或膜的夹心分析中作为捕获或检测剂非常有用，因此在诊断应用中代表了抗体的一种有前途的替代方法。SOMAmer 检测到了产毒艰难梭菌培养上清液中的毒素 A、B 和二元毒素，包括 BI/NAP1 株和历史株。
