Interferon α-2b spray shortened viral shedding time of SARS-CoV-2 Omicron variant: An open prospective cohort study.

Background: The Omicron SARS-CoV-2 variant has spread quickly worldwide due to its effects on virus transmission and vaccine effectiveness. Interferon(IFN) has been shown to have a protective effect against SARS-CoV because of its broad antiviral activity. This study aimed to analyze the treatment effects of IFN α-2b spray in virus clearance of the Omicron SARS-CoV-2 variant. Methods: We examined the effectiveness and safety of IFN α-2b spray in Shanghai, China, with participants infected with the Omicron SARS-CoV-2 variant in an open, prospective cohort study from April 16th to May 5th, 2022. Results: A total of 871 confirmed patients were enrolled in this study. Four hundred and thirteen patients were allocated to the IFN α-2b spray group, and 458 patients were allocated to the control group. The viral shedding time was significantly different between experimental group and control group (11.90 vs.12.58, P <0.05). In the experimental group, the median administration time since the first positive test for SARS-CoV-2 was three days, ranging from 0 to 15 days. There was no obvious adverse effect associated with the spray of IFN α-2b. The univariate Cox regression analysis revealed that the administration time since the first positive test ≤3 days was a protective factor associated with viral shedding time (HR 0.81 95% CI 0.74-0.87, P <0.05). Subgroup analysis showed that the viral shedding time was 10.41 (4.00-16.00) days in the ≤3 days group, which was significantly less than that in the control group (12.58, 95% CI: 7.00-19.15, P <0.0001) and in the >3 days group (13.56, 95%CI: 7.00-22.25, P <0.0001). Conclusions: IFN α-2b spray shortened the viral shedding time of the Omicron SARS-CoV-2 variant when administrated within three days since the first positive test for SARS-CoV-2.

SARS-CoV-2 Spike protein enhances ACE2 expression via facilitating Interferon effects in bronchial epithelium.

OBJECTIVE: In this study, we focused on the interaction between SARS-CoV-2 and host Type I Interferon (IFN) response, so as to identify whether IFN effects could be influenced by the products of SARS-CoV-2. METHODS: All the structural and non-structural proteins of SARS-CoV-2 were transfected and overexpressed in the bronchial epithelial cell line BEAS-2B respectively, and typical antiviral IFN-stimulated gene (ISG) ISG15 expression was detected by qRT-PCR. RNA-seq based transcriptome analysis was performed between control and Spike (S) protein-overexpressed BEAS-2B cells. The expression of ACE2 and IFN effector JAK-STAT signaling activation were detected in control and S protein-overexpressed BEAS-2B cells by qRT-PCR or/and Western blot respectively. The interaction between S protein with STAT1 and STAT2, and the association between JAK1 with downstream STAT1 and STAT2 were measured in BEAS-2B cells by co-immunoprecipitation (co-IP). RESULTS: S protein could activate IFN effects and downstream ISGs expression. By transcriptome analysis, overexpression of S protein induced a set of genes expression, including series of ISGs and the SARS-CoV-2 receptor ACE2. Mechanistically, S protein enhanced the association between the upstream JAK1 and downstream STAT1 and STAT2, so as to promote STAT1 and STAT2 phosphorylation and ACE2 expression. CONCLUSION: SARS-CoV-2 S protein enhances ACE2 expression via facilitating IFN effects, which may help its infection.

[In vitro activity of human recombinant alpha-2b interferon against SARS-CoV-2 virus].

INTRODUCTION: The pandemic spread of a new coronavirus infection, COVID-19, has caused a global emergency and attracted the attention of public health professionals and the population of all countries. A significant increase in the number of new cases of SARS-CoV-2 infection demonstrates the urgency of finding drugs effective against this pathogen.The aim of this work was to evaluate the in vitro antiviral efficacy of human recombinant alpha-2b interferon (IFN-α2b) against SARS-CoV-2 virus. MATERIAL AND METHODS: The experiments had been carried out on Vero Cl008, the continuous line of African green monkey (Chlorocebus sabaeus) kidney cells. The effectiveness of the drugs was assessed by the suppression of viral reproduction in vitro. The biological activity was determined using titration of a virus-containing suspension in a Vero Cl008 cell culture by the formation of negative colonies. RESULTS: The antiviral efficacy of the IFN-α2b-based medications, which have a high safety profile and proven efficacy in the prevention and treatment of influenza and acute respiratory viral infections (ARVI), has been studied against the new pandemic SARS-CoV-2 virus in vitro experiments in Vero C1008 cell culture. IFN-α2b effectively inhibits the reproduction of the virus when applied both 24 hrs before and 2 hrs after infection. In the IFN-α2b concentration range 102-106 IU/ml a complete suppression of the reproduction of the SARS-CoV-2 virus had been demonstrated. DISCUSSION: IFN-α2b demonstrated in vitro high antiviral activity against SARS-CoV-2. In addition, the substance has a high chemotherapeutic index (>1000). CONCLUSION: Medications for intranasal use based on IFN-α2b have high antiviral activity and are promising drugs for in vivo study in terms of prevention and treatment of COVID-19.