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BACKGROUND: The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) has prompted a need for mass testing to identify patients with viral infection. The high demand has created a global bottleneck in testing capacity, which prompted us to modify available resources to extract viral RNA and perform reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) to detect SARS-COV-2. OBJECTIVES: Report on the use of a DNA extraction kit, after modifications, to extract viral RNA that could then be detected using an FDA-approved SARS-COV-2 RT-qPCR assay. MATERIALS AND METHODS: Initially, automated RNA extraction was performed using a modified DNA kit on samples from control subjects, a bacteriophage, and an RNA virus. We then verified the automated extraction using the modified kit to detect in-lab propagated SARSCOV-2 titrations using an FDA approved commercial kit (S, N, and ORF1b genes) and an in-house primer-probe based assay (E, RdRp2 and RdRp4 genes). RESULTS: Automated RNA extraction on serial dilutions SARS-COV-2 achieved successful one-step RT-qPCR detection down to 60 copies using the commercial kit assay and less than 30 copies using the in-house primer-probe assay. Moreover, RT-qPCR detection was successful after automated RNA extraction using this modified protocol on 12 patient samples of SARS-COV-2 collected by nasopharyngeal swabs and stored in viral transport media. CONCLUSIONS: We demonstrated the capacity of a modified DNA extraction kit for automated viral RNA extraction and detection using a platform that is suitable for mass testing. LIMITATIONS: Small patient sample size. CONFLICT OF INTEREST: None.

Summary Autosomal recessive mutations in G6PC3 cause isolated and syndromic congenital neutropenia which includes congenital heart disease and atypical inflammatory bowel disease (IBD). In a highly consanguineous pedigree with novel mutations in G6PC3 and MPL, we performed comprehensive multi-omics analyses. Structural analysis of variant G6PC3 and MPL proteins suggests a damaging effect. A distinct molecular cytokine profile (cytokinome) in the affected proband with IBD was detected. Liquid chromatography-mass spectrometry-based proteomics analysis of the G6PC3-deficient plasma samples identified 460 distinct proteins including 75 upregulated and 73 downregulated proteins. Specifically, the transcription factor GATA4 and LST1 were downregulated while platelet factor 4 (PF4) was upregulated. GATA4 and PF4 have been linked to congenital heart disease and IBD respectively, while LST1 may have perturbed a variety of essential cell functions as it is required for normal cell-cell communication. Together, these studies provide potentially novel insights into the pathogenesis of syndromic congenital G6PC3 deficiency., Graphical abstract, Highlights • Multi-omics approaches identify unique signatures • Whole-exome sequencing reveals distinct cytokine profiles • Expression of GATA4, PF4, and LST1 is dysregulated, Pathophysiology ; Systems Biology ; Genomics ; Proteomics

Background: Sever acute respiratory syndrome Coronavirus-2 (SARS-COV-2) spread prompted mass testing. The main method for testing is by any FDA approved kits for RNA extraction followed by One-Step RT-qPCR based on primer-probe assays. Yet, the high demand for these kits created a global bottleneck in the testing capacity. Methods: We developed a Full-In-House Method (FinHM) suitable for automated viral RNA extraction using full in-house solutions utilizing the MagMaxTM beads followed by an In-House RT-qPCR based on the CDC/WHO recommended ‘primer-probe’ assay targeting the following genes; E, RdRp2, and RdRp4. FinHM was validated by an FDA approved kit that targets S, N, and ORF1b genes made by Thermo Fisher Scientific (TF). Results: The sensitivity and specificity of the automated RNA extraction were evaluated on serial dilutions of in-laboratory propagated SARS-COV-2 with a successful detection down to 46 copies in both assays (P>0.05). Moreover, automated FinHM was successful in extraction of SARS-COV-2 RNA in 266 clinical samples, in which the test results replicated the FDA approved test results (>99% similarity, P>0.05). The In-House RT-qPCR assay had low limit of detection (5 RNA templates), with significant negative correlation between the Ct values and RNA titrations as shown by Pearson correlation (-0.8, -0.8 and -0.7 for E, RdRp2 and RdRp4, respectively). Finally, FinHM was also successful in extraction of SARS-COV-2-spiked plasma and patient plasma samples. Conclusion: We report a reliable, reproducible, specific, sensitive and low-cost platform for automated RNA extraction and detection from SARS-COV-2 and other viruses which is suitable for clinical and mass testing.