Lima Monique da Rocha Queiroz, Nogueira Rita Maria Ribeiro, Filippis Ana Maria Bispo de, Nunes Priscila Conrado Guerra, Sousa Carla Santos de, Silva Manoela Heringer da, Santos Flavia Barreto dos
Flavivirus Laboratory, Oswaldo Cruz Institute, Rio de Janeiro, Brazil.
Flavivirus Laboratory, Oswaldo Cruz Institute, Rio de Janeiro, Brazil.
J Virol Methods. 2014 Aug;204:105-8. doi: 10.1016/j.jviromet.2014.02.031. Epub 2014 Apr 18.
The secreted form of the dengue virus (DENV) nonstructural-1 (NS1) glycoprotein has been shown to be useful for the diagnosis of DENV infections in patients' serum samples. In a number of studies, the sensitivity of the commercially available DENV NS1 glycoprotein detection assays was higher against some DENV serotypes (DENV-1>DENV-3>DENV-2=DENV-4) than others and were also lower using patients' serum samples with secondary versus primary DENV infections. In this study, 471 DENV-4 positive acute phase patients' serum samples were selected from a large panel collected in Brazil from March 2011 to October 2012 by RT-PCR and/or virus isolation followed by serotype determination. The sera from primary (n=228) and secondary (n=238) DENV-4 infections were identified using IgM and IgG capture ELISAs. The sensitivity of a commercial DENV NS1 glycoprotein detection ELISA was then assessed when these serum samples were not pre-treated or pre-treated by acid or heat dissociation prior to being tested. Acid and heat dissociation of patients' serum samples with primary and secondary DENV-4 infections increased significantly the sensitivity of the DENV NS1 glycoprotein detection ELISA from 54.4% to 77.2% (p<0.05) and 82% (p<0.05) and from 39.1% to 63.9% (p<0.05) and 73.1% (p<0.05), respectively. Treatment of DENV infected patients' serum samples using simple and rapid heat dissociation step (100°C for 5min) was, therefore, shown to be very useful for increasing the sensitivity of the DENV NS1 glycoprotein detection ELISA using serum samples from either primary or secondary DENV infected patients.
登革病毒（DENV）非结构蛋白1（NS1）糖蛋白的分泌形式已被证明可用于诊断患者血清样本中的DENV感染。在多项研究中，市售的DENV NS1糖蛋白检测试验对某些DENV血清型（DENV-1>DENV-3>DENV-2=DENV-4）的敏感性高于其他血清型，并且在使用继发感染与原发感染的患者血清样本时敏感性也较低。在本研究中，通过逆转录聚合酶链反应（RT-PCR）和/或病毒分离，随后进行血清型测定，从2011年3月至2012年10月在巴西收集的大量样本中选择了471份DENV-4阳性急性期患者的血清样本。使用IgM和IgG捕获酶联免疫吸附测定（ELISA）鉴定来自原发（n = 228）和继发（n = 238）DENV-4感染的血清。然后在这些血清样本未经预处理或在测试前通过酸或热解离进行预处理时，评估市售DENV NS1糖蛋白检测ELISA的敏感性。原发和继发DENV-4感染患者的血清样本经酸和热解离后，DENV NS1糖蛋白检测ELISA的敏感性分别从54.4%显著提高到77.2%（p<0.05）和82%（p<0.05），以及从39.1%提高到63.9%（p<0.05）和73.1%（p<0.05）。因此，使用简单快速的热解离步骤（100°C，5分钟）处理DENV感染患者的血清样本，对于提高使用原发或继发DENV感染患者血清样本的DENV NS1糖蛋白检测ELISA的敏感性非常有用。
