Graduate School of Veterinary Science, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, 50100, Thailand.
Tiger Kingdom, Mae Rim, Chiang Mai, 50180, Thailand.
BMC Vet Res. 2020 Aug 6;16(1):275. doi: 10.1186/s12917-020-02496-z.
Feline panleukopenia virus (FPV) is an etiologic pathogen of feline panleukopenia that infects all members of Felidae including tigers (Panthera tigris). Vaccinations against FPV among wild felid species have long been practiced in zoos worldwide. However, few studies have assessed the tiger immune response post-vaccination due to the absence of a serological diagnostic tool. To address these limitations, this study aimed to develop an in-house indirect enzyme-linked immunosorbent assay (ELISA) for the monitoring of tiger antibody levels against the feline panleukopenia vaccine by employing the synthesized subunit capsid protein VP2. An in-house horseradish peroxidase (HRP) conjugated rabbit anti-tiger immunoglobulin G (IgG) polyclonal antibody (HRP-anti-tiger IgG) was produced in this study and employed in the assay. It was then compared to a commercial HRP-conjugated goat anti-cat IgG (HRP-anti-cat IgG). Sensitivity and specificity were evaluated using the Bayesian model with preferential conditional dependence between HRP-conjugated antibody-based ELISAs and hemagglutination-inhibition (HI) tests.
The posterior estimates for sensitivity and specificity of two indirect ELISA HRP-conjugated antibodies were higher than those of the HI test. The sensitivity and specificity of the indirect ELISA for HRP-anti-tiger IgG and HRP-anti-cat IgG were 86.5, 57.2 and 86.7%, 64.6%, respectively, while the results of the HI test were 79.1 and 54.1%. In applications, 89.6% (198/221) and 89.1% (197/221) of the tiger serum samples were determined to be seropositive by indirect ELISA testing against HRP-anti-tiger and HRP-anti-cat, respectively.
To the best of our knowledge, the specific serology assays for the detection of the tiger IgG antibody have not yet been established. The HRP-anti-tiger IgG has been produced for the purpose of developing the specific immunoassays for tigers. Remarkably, an in-house indirect ELISA based on VP2 subunit antigen has been successfully developed in this study, providing a potentially valuable serological tool for the effective detection of tiger antibodies.
猫泛白细胞减少症病毒（FPV）是一种引起猫泛白细胞减少症的病原体，可感染包括老虎（Panthera tigris）在内的所有猫科动物。世界各地的动物园长期以来一直对野生动物进行针对 FPV 的疫苗接种。然而，由于缺乏血清学诊断工具，很少有研究评估老虎接种疫苗后的免疫反应。为了解决这些限制，本研究旨在通过使用合成的亚单位衣壳蛋白 VP2 开发一种内部间接酶联免疫吸附试验（ELISA），以监测针对猫泛白细胞减少症疫苗的老虎抗体水平。在这项研究中，生产了内部辣根过氧化物酶（HRP）缀合的兔抗虎免疫球蛋白 G（HRP-anti-tiger IgG）多克隆抗体，并将其用于该检测。然后将其与商业的 HRP 缀合的山羊抗猫 IgG（HRP-anti-cat IgG）进行比较。使用贝叶斯模型评估了敏感性和特异性，该模型优先考虑 HRP 缀合抗体 ELISA 和血凝抑制（HI）测试之间的条件依赖性。
两种间接 ELISA HRP 缀合抗体的敏感性和特异性的后验估计值均高于 HI 测试。间接 ELISA 对 HRP-anti-tiger IgG 和 HRP-anti-cat IgG 的敏感性和特异性分别为 86.5%、57.2%和 86.7%、64.6%，而 HI 测试的结果分别为 79.1%和 54.1%。在应用中，通过间接 ELISA 检测 HRP-anti-tiger 和 HRP-anti-cat，分别有 89.6%（198/221）和 89.1%（197/221）的老虎血清样本被确定为血清阳性。
据我们所知，尚未建立用于检测老虎 IgG 抗体的特异性血清学检测方法。已经生产了 HRP-anti-tiger IgG，目的是开发针对老虎的特异性免疫测定。值得注意的是，本研究成功开发了基于 VP2 亚单位抗原的内部间接 ELISA，为有效检测老虎抗体提供了一种有潜在价值的血清学工具。
