Detection of specific antibodies would be a useful test strategy for bovine tuberculosis (bTB) as a complement to the single skin test. We developed a lateral flow immunochromatography (LFIC) test for rapid bTB detection based on the use of a conjugate of gold nanoparticles with a recombinant G protein. After evaluating 3 Mycobacterium bovis (MB) antigens: ESAT-6, CFP-10 and MPB83 for the control line, we selected MPB83 given it was the most specific. The performance of the test was analyzed with 820 bovine sera, 40 sera corresponding to healthy animals, 5 sera from animals infected with Mycobacterium avium subsp. paratuberculosis (MAP) and 775 sera of animals from herds with bTB. All these sera were also submitted to a validated bTB-ELISA using whole-cell antigen from MB. From the 775 sera of animals from herds with bTB, 87 sera were positive by the bTB-ELISA, 45 were positive by LFIC and only 5 animals were positives by skin test (TST). To confirm bTB infection in the group of TST (−), bTB-ELISA (+) and LFIC (+) animals, we performed postmortem examination in 15 randomly selected animals. Macroscopically, these 15 animals had numerous small and large yellow-white granulomas, characteristic of bTB, and the infection was subsequently confirmed by PCR in these tissues with lesions (gold standard).

No false positive test result was detected with the developed LFIC either with the sera from healthy animals or from animals infected with MAP demonstrating that it can be a useful technique for the rapid identification of animals infected with bTB.

检测特异性抗体将是一种有用的牛结核病 (bTB) 测试策略，作为单一皮肤测试的补充。我们开发了一种横向流动免疫色谱 (LFIC) 测试，用于快速检测 bTB，基于使用金纳米粒子与重组 G 蛋白的缀合物。在评估了 3 种牛分枝杆菌(MB) 抗原：ESAT-6、CFP-10 和 MPB83 作为对照线后，我们选择了 MPB83，因为它是最特异的。用 820 份牛血清、40 份对应于健康动物的血清、5 份来自感染了鸟分枝杆菌亚种的动物的血清分析了测试的性能。副结核病(MAP) 和 775 份来自 bTB 畜群的动物血清。所有这些血清也使用来自 MB 的全细胞抗原进行了验证的 bTB-ELISA。在来自 bTB 畜群的 775 份血清中，87 份血清经 bTB-ELISA 呈阳性，45 份经 LFIC 呈阳性，仅 5 份经皮试 (TST) 呈阳性。为了确认 TST (-)、bTB-ELISA (+) 和 LFIC (+) 动物组中的 bTB 感染，我们对 15 只随机选择的动物进行了尸检。从宏观上看，这 15 只动物有许多大小不一的黄白色肉芽肿，这是 bTB 的特征，随后通过 PCR 在这些有病变的组织中证实了感染（金标准）。

使用来自健康动物或感染 MAP 的动物的血清，使用开发的 LFIC 没有检测到假阳性测试结果，这表明它可以成为快速识别感染 bTB 的动物的有用技术。