ABSTRACT
BACKGROUND: RNA viruses periodically trigger pandemics of severe human diseases, frequently causing enormous economic losses. Here, a nucleic acid extraction-free and amplification-free RNA virus testing probe was proposed for the sensitive and simple detection of classical swine fever virus (CSFV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), based on a double-stranded molecular beacon method. This RNA virus probe contains two base sequences-a recognition strand that binds to the specific domain of CSFV N2 or SARS-CoV-2 N, with a fluorophore (FAM) labeled at the 5' end, and a complementary strand (CSFV-Probe B or SARS-CoV-2-Probe B), combined with a quencher (BHQ2) labeled at the 3' end. RESULTS: Using linear molecular beacon probe technology, the detection limit of the RNA virus probe corresponding to CSFV and SARS-CoV-2 were as low as 0.28 nM and 0.24 nM, respectively. After CSFV E2 and SARS-CoV-2 N genes were transfected into corresponding host cells, the monitoring of RNA virus probes showed that fluorescence signals were dramatically enhanced in a concentration- and time-dependent manner. These results were supported by those of quantitative (qRT-PCR) and visualization (confocal microscopy) analyses. Furthermore, CSF-positive swine samples and simulated SARS-CoV-2 infected mouse samples were used to demonstrate their applicability for different distributions of viral nucleic acids in series tissues. CONCLUSIONS: The proposed RNA virus probe could be used as a PCR-free, cost-effective, and rapid point-of-care (POC) diagnostic platform for target RNA virus detection, holding great potential for the convenient monitoring of different RNA viruses for early mass virus screening.
Subject(s)
COVID-19 , Classical Swine Fever Virus , Nucleic Acids , Animals , COVID-19/diagnosis , Classical Swine Fever Virus/genetics , Mice , Molecular Probes , Polymerase Chain Reaction , SARS-CoV-2/genetics , Sensitivity and Specificity , SwineABSTRACT
Recently, the Wang group at Soochow University and the Gu group at the University of California, Los Angeles demonstrated the targeting ability of platelet-derived extracellular vesicles to deliver anti-inflammatory drug [5-(p-fluorophenyl)-2-ureido] thiophene-3-carboxamide (TPCA-1) to pneumonia for calming the local cytokine storm in acute lung injury.