Cox D L, Akins D R, Porcella S F, Norgard M V, Radolf J D
Division of STD Laboratory Research, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
Mol Microbiol. 1995 Mar;15(6):1151-64. doi: 10.1111/j.1365-2958.1995.tb02288.x.
Controversy exists regarding the constituents and antigenic properties of the Treponema pallidum outer membrane; a major point of contention concerns the cellular location(s) of the spirochaete's lipoprotein immunogens. To address these issues and circumvent problems associated with prior efforts to localize treponemal surface antigens, we developed a novel strategy for investigating T. pallidum molecular architecture. Virulent treponemes were encapsulated in porous agarose beads (gel microdroplets) and then probed in the presence or absence of Triton X-100. Intact, encapsulated treponemes were not labelled by monospecific antisera directed against four major T. pallidum lipoproteins or a candidate T. pallidum outer membrane protein (TpN50) with C-terminal sequence homology to Escherichia coli OmpA or by human or rabbit syphilitic serum. Each of these immunologic reagents, however, labelled encapsulated treponemes co-incubated with detergent. In contrast, antibodies generated against isolated T. pallidum outer membranes labelled intact organisms and the pattern of fluorescence was consistent with the distribution of rare outer membrane proteins visualized by freeze-fracture electron microscopy. In addition to providing strong evidence that the protein portions of treponemal lipoproteins are located within the periplasmic space, these studies have extended our understanding of the topographical relationships among T. pallidum cell envelope constituents. They also demonstrate the feasibility of generating antibodies against rare outer membrane proteins and detecting them on the surfaces of virulent treponemes.
关于梅毒螺旋体外膜的成分和抗原特性存在争议；一个主要的争议点涉及螺旋体脂蛋白免疫原的细胞定位。为了解决这些问题并规避与先前定位梅毒螺旋体表面抗原的努力相关的问题，我们开发了一种研究梅毒螺旋体分子结构的新策略。将有毒力的螺旋体包裹在多孔琼脂糖珠（凝胶微滴）中，然后在有或没有 Triton X - 100 的情况下进行检测。完整的、包裹着的螺旋体不会被针对四种主要梅毒螺旋体脂蛋白或一种与大肠杆菌 OmpA 具有 C 末端序列同源性的候选梅毒螺旋体外膜蛋白（TpN50）的单特异性抗血清标记，也不会被人或兔梅毒血清标记。然而，这些免疫试剂中的每一种都能标记与去污剂共同孵育后的包裹着的螺旋体。相比之下，针对分离的梅毒螺旋体外膜产生的抗体能标记完整的生物体，并且荧光模式与通过冷冻断裂电子显微镜观察到的稀有外膜蛋白的分布一致。除了提供有力证据表明梅毒螺旋体脂蛋白的蛋白质部分位于周质空间外，这些研究还扩展了我们对梅毒螺旋体细胞包膜成分之间拓扑关系的理解。它们还证明了产生针对稀有外膜蛋白的抗体并在有毒力的螺旋体表面检测它们的可行性。
