Multi-omic and comparative analyses revealed monocyte-derived alpha-defensin-1 correlated with COVID-19 severity and inhibited SARS-CoV-2 infection.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiological pathogen of coronavirus disease 2019 (COVID-19), a highly contagious disease, spreading quickly and threatening global public health. The symptoms of COVID-19 vary from mild reactions to severe respiratory distress or even fatal outcomes probably due to the different status of host immunity against the virus. Here in the study, we unveiled plasma proteomic signatures and transcriptional patterns of peripheral blood mononuclear cells (PBMCs) using blood samples of 10 COVID-19 patients with different severity. Through systemic analysis, α-defensin-1 (DEFA1) was identified to be elevated in both plasma and PBMCs, and correlated with disease severity and stages. In vitro study demonstrated that DEFA1 was secreted from immunocytes and suppressed SARS-CoV-2 infection of both original and mutated strains with dose dependency. By using sequencing data, we discovered that DEFA1 was activated in monocytes through NF-κB signaling pathway after infection, and secreted into circulation to perturb SARS-CoV-2 infection by interfering protein kinase C expression. It worked mainly during virus replication instead of entry in host cells. Together, the anti-SARS-CoV-2 mechanism of DEFA1 has unveiled a corner of how innate immunity is against SARS-CoV-2 and explored its clinical potential in disease prognosis and therapeutic intervention.

The bioactivities of sclareol: A mini review.

Sclareol, a diterpene alcohol isolated from the herbal and flavor plant clary sage (Salvia sclarea L.), is far-famed as the predominant ingredient in the refined oil of Salvia sclarea (L.). The empirical medicine of Salvia sclarea L. focused on various diseases, such as arthritis, oral inflammation, digestive system diseases, whereas the sclareol possessed more extensive and characteristic bioactivities, including anti-tumor, anti-inflammation and anti-pathogenic microbes, even anti-diabetes and hypertension. However, there is a deficiency of literature to integrate and illuminate the pharmacological attributes of sclareol based on well-documented investigations. Interestingly, sclareol has been recently considered as the potential candidate against COVID-19 and Parkinson's disease. Accordingly, the bioactive attributes of sclareol in cancer, inflammation, even pharmacochemistry and delivery systems are reviewed for comprehensively dissecting its potential application in medicine.

Antiviral efficacy of selective estrogen receptor modulators against SARS-CoV-2 infection in vitro and in vivo reveals bazedoxifene acetate as an entry inhibitor.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the seventh member of the coronavirus family that can infect humans. Recently, more contagious and pathogenic variants of SARS-CoV-2 have been continuously emerging. Clinical candidates with high efficacy and ready availability are still in urgent need. To identify potent anti-SARS-CoV-2 repurposing drugs, we evaluated the antiviral efficacy of 18 selective estrogen receptor modulators (SERMs) against SARS-CoV-2 infection. Six SERMs exhibited excellent anti-SARS-CoV-2 effects in Vero E6 cells and three human cell lines. Clomifene citrate, tamoxifen, toremifene citrate, and bazedoxifene acetate reduced the weight loss of hamsters challenged with SARS-CoV-2, and reduced hamster pulmonary viral load and interleukin-6 expression when assayed at 4 days postinfection. In particular, bazedoxifene acetate was identified to act on the penetration stage of the postattachment step via altering cholesterol distribution and endosome acidification. And, bazedoxifene acetate inhibited pseudoviruses infection of original SARS-CoV-2, Delta variant, Omicron variant, and SARS-CoV. These results offer critical information supporting bazedoxifene acetate as a promising agent against coronaviruses.

Discovery of potential anti-SARS-CoV-2 drugs based on large-scale screening in vitro and effect evaluation in vivo.

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global crisis. Clinical candidates with high efficacy, ready availability, and that do not develop resistance are in urgent need. Despite that screening to repurpose clinically approved drugs has provided a variety of hits shown to be effective against SARS-CoV-2 infection in cell culture, there are few confirmed antiviral candidates in vivo. In this study, 94 compounds showing high antiviral activity against SARS-CoV-2 in Vero E6 cells were identified from 2,580 FDA-approved small-molecule drugs. Among them, 24 compounds with low cytotoxicity were selected, and of these, 17 compounds also effectively suppressed SARS-CoV-2 infection in HeLa cells transduced with human ACE2. Six compounds disturb multiple processes of the SARS-CoV-2 life cycle. Their prophylactic efficacies were determined in vivo using Syrian hamsters challenged with SARS-CoV-2 infection. Seven compounds reduced weight loss and promoted weight regain of hamsters infected not only with the original strain but also the D614G variant. Except for cisatracurium, six compounds reduced hamster pulmonary viral load, and IL-6 and TNF-α mRNA when assayed at 4 d postinfection. In particular, sertraline, salinomycin, and gilteritinib showed similar protective effects as remdesivir in vivo and did not induce antiviral drug resistance after 10 serial passages of SARS-CoV-2 in vitro, suggesting promising application for COVID-19 treatment.

Isolation and identification of two strains of severe acute respiratory syndrome coronavirus 2 from coronavirus disease 2019 patients in Shanghai

Objective To isolate the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from nasal/throat swabs of coronavirus disease 19 (COVID-19) patients. Methods Three nasal/throat swab samples from COVID-19 patients in Shanghai were treated with TPCK trypsin and were used to treat Vero E6 cells inoculated in 96-well plates. When most of the cells showed obvious cytopathy, the cell culture supernatants were collected. We then detected the viral nucleic acid by fluorescent quantitative real-time polymerase chain reaction, and amplified the gene fragment of the virus receptor binding domain (RBD) by reverse transcription polymerase chain reaction. After amplification and culture, the virus was used to infect the Vero E6 cells inoculated in 96-well plates. The cytopathy was observed and the virus protein was detected by immunofluorescence. Results The Vero E6 cells that cultured with two of three nasal/pharyngeal swab samples showed obvious cytopathic effect and newly synthesized viral nucleic acid was detected in the supernatants of the cell culture. The amplified RBD sequence was completely consistent with the corresponding fragment of SARS-CoV-2 isolated earlier. Virus-infected Vero E6 cells showed cytopathies rapidly and could react with the monoclonal antibody against nucleocapsid protein (N protein) and spike protein (S protein) of SARS-CoV-2, and convalescence sera of COVID-19 patients. Conclusion Two SARS-CoV-2 strains were successfully isolated from two nasal/throat swab samples of COVID-19 patients in Shanghai, which provides evidence for the mechanism research on the infection and pathogenesis of SARS-CoV-2 as well as the development of drugs and vaccines against SARS-CoV-2.

Preparation and verification of severe acute respiratory syndrome Coronavirus 2 Pseudoparticles

Objective: To establish a method for preparing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudoparticles (SARS-CoV-2 pps).