Viral Research and Diagnostic Laboratory, Department of Microbiology, Faculty of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India.
Department of Public Health Dentistry, SriRama Chandra Bhanj Dental College & Hospital, Cuttack, India.
Front Cell Infect Microbiol. 2021 Nov 3;11:717068. doi: 10.3389/fcimb.2021.717068. eCollection 2021.
This study aimed to detect the SARS-COV2 viral component directly from inoculated VTM without RNA extraction. Inoculated VTMs of already tested 50 positive and 50 negative samples were divided into three groups. Group I was treated with Proteinase K (PK) followed by 3-step-heat treatment at different temperatures (25°C, 60°C, and 98°C) and stored at 4°C. Group II was directly subjected to 3-step-heat treatment without PK exposure and stored at 4°C. And group III was set-up as standard group; it was processed using Qiagen's column based QIAamp Nucleic Acid kit and the obtained nucleic acids were stored at 4°C. These stored samples were used as a template to execute real-time polymerase chain reaction, and results were noted. Group I demonstrated 96% and 88% sensitivity for N and ORF1ab genes respectively, whereas group II demonstrated 78% and 60% when compared to the results of standard group III. Overall group I showed better results than group II when compared to group III. Thus, in situations where gold-standard reagents are not available, PK exposure and heat treatment can be employed to carry out molecular detection of SARS-CoV2 viral component.
本研究旨在直接从接种的 VTM 中检测 SARS-COV2 病毒成分，而无需提取 RNA。将已经测试的 50 个阳性和 50 个阴性样本的接种 VTM 分为三组。第一组用蛋白酶 K（PK）处理，然后在不同温度（25°C、60°C 和 98°C）下进行 3 步热处理，并储存在 4°C。第二组直接进行 3 步热处理，不接触 PK，并储存在 4°C。第三组作为标准组；使用 Qiagen 的基于柱的 QIAamp Nucleic Acid 试剂盒处理，获得的核酸储存在 4°C。这些储存的样本被用作模板进行实时聚合酶链反应，并记录结果。第一组在 N 和 ORF1ab 基因上的灵敏度分别为 96%和 88%，而第二组与标准组 III 相比，灵敏度分别为 78%和 60%。总体而言，与标准组 III 相比，第一组的结果优于第二组。因此，在无法获得金标准试剂的情况下，可以采用 PK 暴露和热处理来进行 SARS-CoV2 病毒成分的分子检测。
