Xu Xindong, Cui Xiaobing, Zhu Liufang, Li Zhengli, Zhang Yuanbin, Ma Li, Pan Weiqing
Institute for Infectious Diseases and Vaccine Development, Tongji University School of Medicine, Shanghai, China.
Department of Tropical Infectious Diseases, Second Military Medical University, Shanghai, China.
Front Microbiol. 2018 Jul 25;9:1695. doi: 10.3389/fmicb.2018.01695. eCollection 2018.
Schistosomiasis japonica is one of the most prevalent parasitic diseases in China. The scarcity of effective diagnostic tools is a major factor that contributes to the high prevalence of schistosomiasis japonica. SjSP-13 is a promising serological diagnostic biomarker of the disease. However, it is unclear whether polymorphisms in SjSP-13 affect its diagnostic efficacy and immunogenicity. Here, we found the SjSP-13 gene was highly polymorphic, and all the alleles of the gene were clustered into two clades, clade A and B. SjSP-13.6 and SjSP-13.25, the representative alleles of clade A and B, were produced in . The diagnostic value of SjSP-13.6 (AUC = 0.983 ± 0.006), was found to be similar to the SjSP-13.25 (AUC = 0.973 ± 0.009) by receiver operating characteristic (ROC) analysis. SjSP-13.6 and SjSP-13.25 have the same specificity (96.7%), while the sensitivity of SjSP-13.6 (90.4%) is slightly but not significantly higher than SjSP-13.25 (85.2%). The combination use of the two alleles (SjSP-13.6/25) didn't increase the diagnostic performance of SjSP-13 as the AUC value of SjSP-13.6/25 is 0.977 ± 0.009, lower than individual SjSP-13.6 (AUC = 0.983 ± 0.006). In addition, we found the immunogenicity of clade A alleles is significantly higher than clade B in naturally infected animals and patients, as the mean antibody levels of SjSP-13.6 was significantly higher than SjSP-13.25. We conclude that polymorphisms of the SjSP-13 gene should not affect its diagnostic efficacy, and it is not necessary to combine the alleles of the two clades for diagnosis of schistosomiasis.
日本血吸虫病是中国最流行的寄生虫病之一。有效诊断工具的匮乏是导致日本血吸虫病高流行率的一个主要因素。SjSP - 13是该疾病一种有前景的血清学诊断生物标志物。然而，尚不清楚SjSP - 13中的多态性是否会影响其诊断效力和免疫原性。在此，我们发现SjSP - 13基因高度多态，且该基因的所有等位基因聚为两个进化枝，进化枝A和B。进化枝A和B的代表性等位基因SjSP - 13.6和SjSP - 13.25在……中产生。通过受试者工作特征（ROC）分析发现，SjSP - 13.6（AUC = 0.983 ± 0.006）的诊断价值与SjSP - 13.25（AUC = 0.973 ± 0.009）相似。SjSP - 13.6和SjSP - 13.25具有相同的特异性（96.7%），而SjSP - 13.6的敏感性（90.4%）略高于SjSP - 13.25（85.2%），但差异不显著。两个等位基因（SjSP - 13.6/25）联合使用并未提高SjSP - 13的诊断性能，因为SjSP - 13.6/25的AUC值为0.977 ± 0.009，低于单个的SjSP - 13.6（AUC = 0.983 ± 0.006）。此外，我们发现在自然感染动物和患者中，进化枝A等位基因的免疫原性显著高于进化枝B，因为SjSP - 13.6的平均抗体水平显著高于SjSP - 13.25。我们得出结论，SjSP - 13基因的多态性不应影响其诊断效力，且诊断日本血吸虫病无需将两个进化枝的等位基因联合使用。
