Peterson E M, Zhong G M, Carlson E, de la Maza L M
Department of Pathology, University of California, Irvine 92717.
Infect Immun. 1988 Apr;56(4):885-91. doi: 10.1128/iai.56.4.885-891.1988.
Neutralization of the infectivity of Chlamydia trachomatis was assessed by using polyclonal antisera and monoclonal antibodies (MAbs). Polyclonal antisera and a species-reactive MAb as well as a subspecies-specific MAb, both of which were directed toward the major outer membrane protein of C. trachomatis, reduced the number of chlamydial inclusion-forming units in an in vitro assay. Neutralization was dependent on the presence of complement. The species-specific MAb reacted with all 15 serovars by a microimmunofluorescence assay and a dot blot enzyme-linked immunosorbent assay with heat-treated elementary bodies. On the other hand, this same MAb reacted with all serovars, except those in the C complex, by the dot blot enzyme-linked immunosorbent assay with viable organisms and neutralized in vitro all 10 serovars tested, except those in the C complex. When neutralization assays were performed in a solution containing Mg2+, neutralization by both polyclonal antisera and MAbs was significantly reduced. A dose response to Mg2+ supplied as MgSO4 revealed that all concentrations tested from 50 to 800 microM had some effect. Concentrations of greater than or equal to 400 microM MgSO4 completely abolished neutralization at the lowest dilution of polyclonal antisera and species-reactive MAb tested. Although Mg2+ also blocked the neutralization effect of the subspecies-specific MAb, this neutralization was not as complete as that observed with the species-reactive MAb. Addition of Mg2+ to the assay over the initial 45 min of incubation of C. trachomatis with MAb and complement showed that the organisms could be rescued to some extent over the first 30 min of incubation, after which time neutralization of infectivity could not be reversed. C. trachomatis treated with Mg2+, the species-reactive MAb, and complement were lethal to mice in an in vivo toxicity and infectivity assay, whereas mice injected with organisms incubated with the same MAb and complement without Mg2+ survived.
通过使用多克隆抗血清和单克隆抗体（MAb）评估沙眼衣原体感染性的中和作用。多克隆抗血清、一种种属反应性单克隆抗体以及一种亚种特异性单克隆抗体，这两种抗体均针对沙眼衣原体的主要外膜蛋白，在体外试验中减少了衣原体包涵体形成单位的数量。中和作用依赖于补体的存在。通过微量免疫荧光试验和用热处理的原体进行的斑点印迹酶联免疫吸附试验，种属特异性单克隆抗体与所有15个血清型发生反应。另一方面，通过用活生物体进行的斑点印迹酶联免疫吸附试验，这种相同的单克隆抗体与除C复合物中的血清型外的所有血清型发生反应，并在体外中和了所有测试的10个血清型，除了C复合物中的血清型。当在含有Mg2+的溶液中进行中和试验时，多克隆抗血清和单克隆抗体的中和作用均显著降低。以MgSO4形式提供的Mg2+的剂量反应表明，测试的所有浓度从50至800微摩尔/升都有一定作用。浓度大于或等于400微摩尔/升的MgSO4在测试的多克隆抗血清和种属反应性单克隆抗体的最低稀释度下完全消除了中和作用。虽然Mg2+也阻断了亚种特异性单克隆抗体的中和作用，但这种中和作用不如种属反应性单克隆抗体观察到的那样完全。在沙眼衣原体与单克隆抗体和补体孵育的最初45分钟内添加Mg2+表明，在孵育的前30分钟内生物体可以在一定程度上得到挽救，此后感染性的中和作用无法逆转。在体内毒性和感染性试验中，用Mg2+、种属反应性单克隆抗体和补体处理的沙眼衣原体对小鼠是致死性的，而注射了与相同单克隆抗体和补体但无Mg2+孵育的生物体的小鼠存活下来。
