Ndiaye Oumar, Diagne Cheikh Tidiane, Abd El Wahed Ahmed, Dia Fatou, Dia Moussa, Faye Adama, Leal Silvania Da Veiga, Dos Santos Menilita, Lima Mendonça Maria da Luz de, da Silva Leite Carolina Cardoso, Bouh Boye Cheikh Saad, Bryant Juliet E, Desprès Philippe, Faye Ousmane, Sall Amadou Alpha, Faye Oumar
Virology Department, Institut Pasteur de Dakar, Dakar BP 220, Senegal.
Institut de Santé et Développement (ISED), Université Cheikh Anta DIOP de Dakar, Dakar BP 16390, Senegal.
Diagnostics (Basel). 2023 Jan 26;13(3):462. doi: 10.3390/diagnostics13030462.
Zika virus (ZIKV) diagnostics are crucial for proper antenatal and postnatal care and also for surveillance and serosurvey studies. Since the viremia during ZIKV infection is fleeting, serological testing is highly valuable to inform diagnosis. However, current serology tests using whole virus antigens frequently suffer from cross reactivity issues, delays, and technical complexity, especially in low and middle income countries (LMICs) and endemic countries. Here, we describe an indirect ELISA to detect specific IgG antibodies using the ZIKV envelope domain III (EDIII) protein expressed in Drosophila S2 cells as an immunogen. Using a total of 367 clinical samples, we showed that the EDIII-ELISA was able to detect IgG antibodies against ZIKV with high sensitivity of 100.0% and specificity of 94.7% when compared to plaque reduction neutralization tests (PRNTs) as the gold standard and using 0.208 as the cut-off OD value. These results show the usefulness of the recombinant envelope domain III as an alternative to standard whole virus proteins for ZIKV diagnostics as it improves the sensitivity and specificity of IgG ELISA assay when used as an immunogen. This method should, therefore, be extended to serological diagnostic techniques for other members of the flavivirus genus and for use in IgM diagnostic testing.
寨卡病毒（ZIKV）诊断对于适当的产前和产后护理以及监测和血清学调查研究至关重要。由于寨卡病毒感染期间的病毒血症短暂，血清学检测对于诊断具有很高的价值。然而，目前使用全病毒抗原的血清学检测经常存在交叉反应问题、延迟和技术复杂性，特别是在低收入和中等收入国家（LMICs）以及流行国家。在此，我们描述了一种间接ELISA，使用在果蝇S2细胞中表达的寨卡病毒包膜结构域III（EDIII）蛋白作为免疫原，来检测特异性IgG抗体。使用总共367份临床样本，我们表明，与作为金标准的蚀斑减少中和试验（PRNTs）相比，当使用0.208作为临界OD值时，EDIII-ELISA能够以100.0%的高灵敏度和94.7%的特异性检测抗寨卡病毒的IgG抗体。这些结果表明，重组包膜结构域III作为寨卡病毒诊断中标准全病毒蛋白的替代物是有用的，因为当用作免疫原时，它提高了IgG ELISA检测的灵敏度和特异性。因此，这种方法应扩展到用于黄病毒属其他成员的血清学诊断技术以及IgM诊断检测。
