Chung Chungwon J, Clavijo Alfonso, Bounpheng Mangkey A, Uddowla Sabena, Sayed Abu, Dancho Brooke, Olesen Ian C, Pacheco Juan, Kamicker Barbara J, Brake David A, Bandaranayaka-Mudiyanselage Carey L, Lee Stephen S, Rai Devendra K, Rieder Elizabeth
U.S. Department of Homeland Security Science & Technology Directorate (Chung) Plum Island Animal Disease Center, Greenport, NY.
Institute for Infectious Animal Diseases, College Station, TX (Clavijo).
J Vet Diagn Invest. 2018 Sep;30(5):699-707. doi: 10.1177/1040638718779641. Epub 2018 Jun 19.
The highly contagious foot-and-mouth disease virus (FMDV) afflicts cloven-hoofed animals, resulting in significant costs because of loss of trade and recovery from disease. We developed a sensitive, specific, and rapid competitive ELISA (cELISA) to detect serum antibodies to FMDV. The cELISA utilized a monoclonal blocking antibody specific for a highly conserved FMDV nonstructural 3B epitope, a recombinant mutant FMDV 3ABC coating protein, and optimized format variables including serum incubation for 90 min at 20-25°C. Samples from 16 animals experimentally infected with one FMDV serotype (A, O, Asia, or SAT-1) demonstrated early detection capacity beginning 7 d post-inoculation. All samples from 55 vesicular stomatitis virus antibody-positive cattle and 44 samples from cloven-hoofed animals affected by non-FMD vesicular diseases were negative in the cELISA, demonstrating 100% analytical specificity. The diagnostic sensitivity was 100% against sera from 128 cattle infected with isolates of all FMDV serotypes, emphasizing serotype-agnostic results. Diagnostic specificities of U.S. cattle ( n = 1135) and swine ( n = 207) sera were 99.4% and 100%, respectively. High repeatability and reproducibility were demonstrated with 3.1% coefficient of variation in percent inhibition data and 100% agreement using 2 kit lots and 400 negative control serum samples, with no difference between bench and biosafety cabinet operation. Negative results from vaccinated, uninfected cattle, pig, and sheep sera confirmed the DIVA (differentiate infected from vaccinated animals) capability. This rapid (<3 h), select agent-free assay with high sensitivity and specificity, DIVA capability, and room temperature processing capability will serve as a useful tool in FMDV surveillance, emergency preparedness, response, and outbreak recovery programs.
高传染性的口蹄疫病毒（FMDV）会感染偶蹄类动物，由于贸易损失和疾病恢复成本，会导致巨大的经济损失。我们开发了一种灵敏、特异且快速的竞争ELISA（cELISA）来检测口蹄疫病毒的血清抗体。该cELISA使用了一种针对高度保守的口蹄疫病毒非结构3B表位的单克隆阻断抗体、一种重组突变口蹄疫病毒3ABC包被蛋白，并优化了包括血清在20-25°C孵育90分钟在内的反应形式变量。来自16只经一种口蹄疫病毒血清型（A、O、亚洲或SAT-1）实验感染的动物的样本在接种后7天开始显示出早期检测能力。来自55只水泡性口炎病毒抗体阳性牛的所有样本以及来自受非口蹄疫水泡性疾病影响的偶蹄类动物的44个样本在cELISA中均为阴性，显示出100%的分析特异性。对来自128只感染了所有口蹄疫病毒血清型分离株的牛的血清，诊断敏感性为100%，强调了血清型无关的结果。美国牛（n = 1135）和猪（n = 207）血清的诊断特异性分别为99.4%和100%。使用2个试剂盒批次和400个阴性对照血清样本，抑制率数据的变异系数为3.1%，一致性为100%，证明了高重复性和再现性，且在实验台和生物安全柜操作之间无差异。接种疫苗但未感染的牛、猪和羊血清的阴性结果证实了其区分感染动物和接种动物（DIVA）的能力。这种快速（<3小时）、无需选择病原体的检测方法具有高灵敏度和特异性、DIVA能力以及室温处理能力，将成为口蹄疫病毒监测、应急准备、应对和疫情恢复计划中的有用工具。
