CDetection.v2: One-pot assay for the detection of SARS-CoV-2.

Introduction: The ongoing 2019 coronavirus disease pandemic (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and its variants, is a global public health threat. Early diagnosis and identification of SARS-CoV-2 and its variants plays a critical role in COVID-19 prevention and control. Currently, the most widely used technique to detect SARS-CoV-2 is quantitative reverse transcription real-time quantitative PCR (RT-qPCR), which takes nearly 1 hour and should be performed by experienced personnel to ensure the accuracy of results. Therefore, the development of a nucleic acid detection kit with higher sensitivity, faster detection and greater accuracy is important. Methods: Here, we optimized the system components and reaction conditions of our previous detection approach by using RT-RAA and Cas12b. Results: We developed a Cas12b-assisted one-pot detection platform (CDetection.v2) that allows rapid detection of SARS-CoV-2 in 30 minutes. This platform was able to detect up to 5,000 copies/ml of SARS-CoV-2 without cross-reactivity with other viruses. Moreover, the sensitivity of this CRISPR system was comparable to that of RT-qPCR when tested on 120 clinical samples. Discussion: The CDetection.v2 provides a novel one-pot detection approach based on the integration of RT-RAA and CRISPR/Cas12b for detecting SARS-CoV-2 and screening of large-scale clinical samples, offering a more efficient strategy for detecting various types of viruses.

New laboratory evidence for the association between endothelial dysfunction and COVID-19 disease progression.

There is growing evidence that angiotensin-converting enzyme 2 is highly expressed on endothelial cells, endothelial dysfunction plays a critical role in coronavirus disease 2019 (COVID-19) progression, but laboratory evidence is still lacking. This study established a multicenter retrospective cohort of 966 COVID-19 patients from three hospitals in Wuhan, China. We found that male (62.8% vs. 46.5%), old age [72 (17) vs. 60.5 (21)], and coexisting chronic diseases (88.5% vs. 60.0%) were associated with poor clinical prognosis in COVID-19. Furthermore, the deteriorated patients exhibited more severe multiorgan damage, coagulation dysfunction, and extensive inflammation. Additionally, a cross-sectional study including 41 non-COVID-19 controls and 39 COVID-19 patients assayed endothelial function parameters in plasma and showed that COVID-19 patients exhibited elevated vascular cell adhesion molecule-1 (VCAM-1) (median [IQR]: 0.32 [0.27] vs. 0.17 [0.11] µg/ml, p < 0.001), E-selectin (21.06 [12.60] vs. 11.01 [4.63] ng/ml, p < 0.001), tissue-type plasminogen activator (tPA) (0.22 [0.12] vs. 0.09 [0.04] ng/ml, p < 0.001), and decreased plasminogen activator inhibitor-1 (0.75 [1.31] vs 6.20 [5.34] ng/ml, p < 0.001), as compared to normal controls. Moreover, VCAM-1 was positively correlated with d-dimer (R = 0.544, p < 0.001); tPA was positively correlated with d-dimer (R = 0.800, p < 0.001) and blood urea nitrogen (R = 0.638, p < 0.001). Our findings further confirm the strong association between endothelial dysfunction and poor prognosis of COVID-19, which offers a rationale for targeting endothelial dysfunction as a therapeutic strategy for COVID-19.

Angiotensin-Converting Enzyme Genotype-Specific Immune Response Contributes to the Susceptibility of COVID-19: A Nested Case-Control Study.

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of coronavirus disease 2019 (COVID-19), which has resulted in a global pandemic. Methodology: We used a two-step polymerase chain reaction to detect the ACE genotype and ELISA kits to detect the cytokine factor. We also used proteomics to identify the immune pathway related to the ACE protein expression. Result: In this study, we found that the angiotensin-converting enzyme (ACE) deletion polymorphism was associated with the susceptibility to COVID-19 in a risk-dependent manner among the Chinese population. D/D genotype distributions were higher in the COVID-19 disease group than in the control group (D/D odds ratio is 3.87 for mild (p value < 0.0001), 2.59 for moderate (p value = 0.0002), and 4.05 for severe symptoms (p value < 0.0001), logic regression analysis. Moreover, genotype-specific cytokine storms and immune responses were found enriched in patients with the ACE deletion polymorphism, suggesting the contribution to the susceptibility to COVID-19. Finally, we identified the immune pathway such as the complement system related to the ACE protein expression of patients by lung and plasma proteomics. Conclusion: Our results demonstrated that it is very important to consider gene polymorphisms in the population to discover a host-based COVID-19 vaccine and drug design for preventive and precision medicine.