Prospects of Coffee Leaf against SARS-CoV-2 Infection.

In the current climate, many countries are in dire need of effective preventive methods to curb the Severe Acute Respiratory Syndrome Coronavirus Type 2 (SARS-CoV-2) pandemic. The purpose of this research is to screen and explore natural plant extracts that have the potential to against SARS-CoV-2 and provide alternative options for SARS-CoV-2 prevention and hand sanitizer or spray-like disinfectants. We first used Spike-ACE2 ELISA and TMPRSS2 fluorescence resonance energy transfer (FRET) assays to screen extracts from agricultural by-products from Taiwan with the potential to impede SARS-CoV-2 infection. Next, the SARS-CoV-2 pseudo-particles (Vpp) infection assay was tested to validate the effectiveness. We identified an extract from coffee leaf (Coffea Arabica), a natural plant that effectively inhibited wild-type SARS-CoV-2, and five Variants of Concern (Alpha, Beta, Gamma, Delta, and Omicron strain) from entering host cells. In an attempt to apply coffee leaf extract for hand sanitizer or spray-like disinfectants, we designed a skin-like gelatin membrane experiment. We showed that the high concentration of coffee leaf extract on the skin surface could block SARS-CoV-2 into cells more potently than 75% Ethanol, a standard disinfectant to inactivate SARS-CoV-2. Finally, LC-HRMS analysis was used to identify compounds such as caffeine, chlorogenic acid (CGA), quinic acid, and mangiferin that are associated with an anti-SARS-CoV-2 activity. Our results demonstrated that coffee leaf extract, an agricultural by-product effectively inhibits SARS-CoV-2 Vpp infection through an ACE2-dependent mechanism and may be utilized to develop products against SARS-CoV-2 infection.

NK cell receptor and ligand composition influences the clearance of SARS-CoV-2.

To explore how the immune system controls clearance of SARS-CoV-2, we used a single-cell, mass cytometry-based proteomics platform to profile the immune systems of 21 patients who had recovered from SARS-CoV-2 infection without need for admission to an intensive care unit or for mechanical ventilation. We focused on receptors involved in interactions between immune cells and virus-infected cells. We found that the diversity of receptor repertoires on natural killer (NK) cells was negatively correlated with the viral clearance rate. In addition, NK subsets expressing the receptor DNAM1 were increased in patients who more rapidly recovered from infection. Ex vivo functional studies revealed that NK subpopulations with high DNAM1 expression had cytolytic activities in response to target cell stimulation. We also found that SARS-CoV-2 infection induced the expression of CD155 and nectin-4, ligands of DNAM1 and its paired coinhibitory receptor TIGIT, which counterbalanced the cytolytic activities of NK cells. Collectively, our results link the cytolytic immune responses of NK cells to the clearance of SARS-CoV-2 and show that the DNAM1 pathway modulates host-pathogen interactions during SARS-CoV-2 infection.

Combined intravenous immunoglobulin and baricitinib treatment for severe COVID-19 with rhabdomyolysis: A case report.

Since December 2019, the outbreak of coronavirus disease 2019 (COVID-19) has spread rapidly around the world. The severity of COVID-19 ranges from asymptomatic carriers to severe acute respiratory distress syndrome (ARDS). Accumulating evidence has shown that COVID-19 may be associated with multiple organ complications including cardiac injury, viral myositis and neurological deficits. Numerous laboratory biomarkers including lymphocytes, platelets, lactate dehydrogenase and creatine kinase (CK) have been associated with the prognostic outcomes of patients with COVID-19. However, dynamic correlations between levels of biomarkers and clinical course have not been studied. Herein, we report a 74-year-old female patient with severe COVID-19 which progressed to ARDS requiring intubation and mechanical ventilation. The laboratory findings showed lymphopenia, hypogammaglobulinemia, and elevated inflammatory biomarkers and CK. She received intensive therapy with hydroxychloroquine, lopinavir/ritonavir, and azithromycin with limited effects. Immunomodulatory treatments with high dose intravenous immunoglobulin and baricitinib were prescribed with satisfactory biochemical, radiographic and clinical recovery. We found an interesting correlation between serum CK elevation and inflammatory biomarkers, which reflected clinical improvement. This case demonstrates that inflammatory biomarkers, cytokines, and CK level correlated with disease severity and treatment response, and combined use of intravenous immunoglobulin and baricitinib is a potential treatment in patients with severe COVID-19.