Southern Timothy, Bess Leah, Harmon Jillian, Taylor Lacey, Caldwell Harlan
Laboratory of Intracellular Parasites, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA.
Clin Vaccine Immunol. 2012 Nov;19(11):1864-9. doi: 10.1128/CVI.00460-12. Epub 2012 Sep 26.
Chlamydia trachomatis is an obligate intracellular mucosotropic pathogen that causes human infections of global importance. C. trachomatis causes trachoma, the leading cause of preventable blindness worldwide, and is the most common cause of bacterial sexually transmitted disease. Although oculogenital infections are treatable with antibiotics, a vaccine is needed to control C. trachomatis infection. Ideally, a vaccine would provide coverage against most, if not all, naturally occurring antigenically distinct serovariants. The development of a subunit vaccine to prevent oculogenital disease could be advanced by identifying chlamydial antigens that elicit pan-neutralizing antibodies, particularly among infected human populations of known risk factors. There is currently no objective high-throughput in vitro assay to screen human sera for neutralization to aid in identification of these antigens. This report describes an objective, high-throughput in vitro assay that measures C. trachomatis-neutralizing antibodies. Antibody-mediated neutralization of chlamydial infection was performed in a 96-well microtiter format, and neutralization was quantified by immunostaining fixed cells followed by automated fluorometric analysis. This report shows that fluorometric analysis of C. trachomatis infection directly correlates to labor-intensive manual inclusion counts. Furthermore, this report shows that fluorometry can be used to identify C. trachomatis serovar- and serocomplex-specific neutralization. This objective, high-throughput analysis of serum neutralization is amenable to epidemiological studies of human chlamydial infection, human clinical vaccine trials, and preclinical animal model experiments of Chlamydia infection.
沙眼衣原体是一种专性细胞内亲黏膜病原体，可引发具有全球重要性的人类感染。沙眼衣原体可导致沙眼，这是全球可预防失明的主要原因，也是细菌性性传播疾病最常见的病因。虽然眼生殖器感染可用抗生素治疗，但仍需要一种疫苗来控制沙眼衣原体感染。理想情况下，一种疫苗应能针对大多数（如果不是全部）天然存在的抗原性不同的血清变种提供保护。通过鉴定能引发泛中和抗体的衣原体抗原，尤其是在已知风险因素的感染人群中，可以推动预防眼生殖器疾病的亚单位疫苗的研发。目前尚无客观的高通量体外试验来筛选人血清中的中和作用，以帮助鉴定这些抗原。本报告描述了一种客观的高通量体外试验，用于检测沙眼衣原体中和抗体。衣原体感染的抗体介导中和作用以96孔微量滴定板形式进行，中和作用通过对固定细胞进行免疫染色，然后进行自动荧光分析来定量。本报告表明，对沙眼衣原体感染的荧光分析与劳动强度大的人工包涵体计数直接相关。此外，本报告表明，荧光测定法可用于鉴定沙眼衣原体血清型和血清复合体特异性中和作用。这种对血清中和作用的客观、高通量分析适用于人类沙眼衣原体感染的流行病学研究、人类临床疫苗试验以及衣原体感染的临床前动物模型实验。
