Graduate Institute of Veterinary Pathobiology, National Chung Hsing University, Taichung 40227, Taiwan.
National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli 35053, Taiwan.
Toxins (Basel). 2020 Sep 5;12(9):572. doi: 10.3390/toxins12090572.
Cobra snakes (genus ) are some of the most dangerous snake species in Asia and Africa, as their bites cause severe life-threatening respiratory failure and local tissue destruction, especially in the case of late diagnosis. The differential diagnosis of snakebite envenomation still mainly relies upon symptomatology, the patient's description, and the experience of physicians. We have designed a rapid test, immunochromatographic test of cobra (ICT-Cobra), which obtained fair results in improving the diagnosis and treatment of snakebites in Taiwan. In this study, we further investigated the feasibility of applying the kit for the detection of other cobra venoms based on the potential interspecies similarity. We firstly demonstrated the cross-reactivity between eight venoms of medically important cobra species and the rabbit anti- IgG that was used in ICT-Cobra by Western blotting and sandwich enzyme-linked immunosorbent assay. Then, ICT-Cobra was used to detect various concentrations of the eight venoms to elucidate its performance. Noticeable correlations between the cross-reactivity of venoms from genus snakes and existing geographical characteristics were found. ICT-Cobra could detect venoms from other Asian cobras with variable detection limits comparable to those observed for , but the kit was less successful in the detection of venom from African cobras. The similar but slightly different venom components and the interaction between venom and rabbit anti- IgG led to variations in the detection limits. The transcontinental usage of ICT-Cobra might be possible due to the cross-reactivity of antibodies and similarities among the larger-sized proteins. This study showed that the close immunological relationships in the genus could be used to develop a venom detection kit for the diagnosis of cobra envenomation in both Asian and African regions. Additional clinical studies and technical adjustments are still needed to improve the efficacy and broadening the application of ICT-Cobra in the future.
眼镜蛇（属）是亚洲和非洲最危险的蛇类之一，因为它们的咬伤会导致严重的危及生命的呼吸衰竭和局部组织破坏，尤其是在诊断较晚的情况下。蛇咬伤中毒的鉴别诊断主要仍依赖于症状、患者描述和医生的经验。我们设计了一种快速检测试剂盒，即免疫层析法检测眼镜蛇（ICT-Cobra），该试剂盒在提高台湾地区蛇咬伤的诊断和治疗方面取得了良好的效果。在这项研究中，我们进一步根据种间潜在的相似性，研究了该试剂盒应用于检测其他眼镜蛇毒液的可行性。我们首先通过 Western blot 和夹心酶联免疫吸附试验证实了 8 种重要的眼镜蛇毒液与 ICT-Cobra 中使用的兔抗 IgG 之间的交叉反应性。然后，我们使用 ICT-Cobra 检测了不同浓度的 8 种毒液，以阐明其性能。在属蛇的毒液交叉反应性和现有的地理特征之间发现了明显的相关性。ICT-Cobra 可以检测到来自亚洲其他眼镜蛇的毒液，其检测限与观察到的 相似，但该试剂盒在检测来自非洲眼镜蛇的毒液时效果较差。相似但略有不同的毒液成分以及毒液与兔抗 IgG 的相互作用导致了检测限的变化。由于抗体的交叉反应性和较大蛋白之间的相似性，ICT-Cobra 可能可以在跨大陆使用。这项研究表明，属内的密切免疫关系可用于开发用于诊断亚洲和非洲地区眼镜蛇中毒的毒液检测试剂盒。未来仍需要更多的临床研究和技术调整，以提高 ICT-Cobra 的疗效，并拓宽其应用范围。
