Therapeutics and Vaccines: Strengthening Our Fight Against the Global Pandemic COVID-19

SARS-CoV-2 Vaccines, Vaccine Development Technologies, and Significant Efforts in Vaccine Development during the Pandemic: The Lessons Learned Might Help to Fight against the Next Pandemic

We are currently approaching three years since the beginning of the coronavirus disease 2019 (COVID-19) pandemic. SARS-CoV-2 has caused extensive disruptions in everyday life, public health, and the global economy. Thus far, the vaccine has worked better than expected against the virus. During the pandemic, we experienced several things, such as the virus and its pathogenesis, clinical manifestations, and treatments; emerging variants; different vaccines; and the vaccine development processes. This review describes how each vaccine has been developed and approved with the help of modern technology. We also discuss critical milestones during the vaccine development process. Several lessons were learned from different countries during the two years of vaccine research, development, clinical trials, and vaccination. The lessons learned during the vaccine development process will help to fight the next pandemic.

Sertraline Is an Effective SARS-CoV-2 Entry Inhibitor Targeting the Spike Protein

The global spread of the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the continuously emerging new variants underscore an urgent need for effective therapeutics for the treatment of coronavirus disease 2019 (COVID-19). Here, we screened several FDA-approved amphiphilic drugs and determined that sertraline (SRT) exhibits potent antiviral activity against infection of SARS-CoV-2 pseudovirus (PsV) and authentic virus in vitro. It effectively inhibits SARS-CoV-2 spike (S)-mediated cell-cell fusion. SRT targets the early stage of viral entry. It can bind to the S1 subunit of the S protein, especially the receptor binding domain (RBD), thus blocking S-hACE2 interaction and interfering with the proteolysis process of S protein. SRT is also effective against infection with SARS-CoV-2 PsV variants, including the newly emerging Omicron. The combination of SRT and other antivirals exhibits a strong synergistic effect against infection of SARS-CoV-2 PsV. The antiviral activity of SRT is independent of serotonin transporter expression. Moreover, SRT effectively inhibits infection of SARS-CoV-2 PsV and alleviates the inflammation process and lung pathological alterations in transduced mice in vivo. Therefore, SRT shows promise as a treatment option for COVID-19. IMPORTANCE The study shows SRT is an effective entry inhibitor against infection of SARS-CoV-2, which is currently prevalent globally. SRT targets the S protein of SARS-CoV-2 and is effective against a panel of SARS-CoV-2 variants. It also could be used in combination to prevent SARS-CoV-2 infection. More importantly, with long history of clinical use and proven safety, SRT might be particularly suitable to treat infection of SARS-CoV-2 in the central nervous system and optimized for treatment in older people, pregnant women, and COVID-19 patients with heart complications, which are associated with severity and mortality of COVID-19.

A Study on the Evaluation of the Public Health Governance in Countries along the Belt and Road Initiative (BRI)

Social resilience for public health is a new theoretical framework for understanding public health risk governance capacity. This study identifies 18 indicators from the publicly available database and adopts the method of multivariable analysis to evaluate the level of social resilience for public health in 73 countries along the Belt and Road Initiative (BRI). The study finds that the main influencing factors of social resilience for public health are institutional resilience, physical resilience, and participation resilience. The capacity of public health risk governance in countries along the BRI is classified into three levels: high, medium, and low. A high level of public health risk governance capacity is mainly shown in developed European countries such as Italy, rich Southwestern Asian countries such as the United Arab Emirates, and East Asian countries represented by Japan, South Korea, and Singapore. The middle-level countries are mainly distributed at the junction of Eurasia, which Russia represents. The low-level countries are primarily distributed in South Asia, Africa, and the war zones. In general, countries along the BRI have polarized the capacity of public health risk governance and structural inequalities, mainly manifested in large differences in the organizational capacity and mobilization capacity between countries in response to public health risk events, and the gap between the rich and the poor within a country. Under such circumstances, the building of a Community of Common Health is required to be accelerated.

A hybrid soluble gp130/spike-nanobody fusion protein simultaneously blocks IL-6 trans-signaling and cellular infection with SARS-CoV2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can induce mild to life-threatening symptoms. Especially individuals over 60 years of age or with underlying comorbidities, including heart or lung disease and diabetes, or immunocompromised patients are at a higher risk. Fatal multiorgan damage in coronavirus disease 2019 (COVID-19) patients can be attributed to an interleukin-6 (IL-6)-dominated cytokine storm. Consequently, IL-6 receptor (IL-6R) monoclonal antibody treatment for severe COVID-19 cases has been approved for therapy. High concentrations of soluble IL-6R (sIL-6R) were found in COVID-19 intensive care unit patients, suggesting the involvement of IL-6 trans-signaling in disease pathology. Here, in analogy to bispecific antibodies (bsAbs), we developed the first bispecific IL-6 trans-signaling inhibitor, c19s130Fc, which blocks viral infection and IL-6 trans-signaling. c19s130Fc is a designer protein of the IL-6 trans-signaling inhibitor cs130 fused to a single-domain nanobody directed against the receptor binding domain (RBD) of the SARS-CoV-2 spike protein. c19s130Fc binds with high affinity to IL-6:sIL-6R complexes as well as the spike protein of SARS-CoV-2, as shown by surface plasmon resonance. Using cell-based assays, we demonstrate that c19s130Fc blocks IL-6 trans-signaling-induced proliferation and STAT3 phosphorylation in Ba/F3-gp130 cells as well as SARS-CoV-2 infection and STAT3 phosphorylation in Vero cells. Taken together, c19s130Fc represents a new class of bispecific inhibitors consisting of a soluble cytokine receptor fused to antiviral nanobodies and principally demonstrates the multifunctionalization of trans-signaling inhibitors.

IMPORTANCE The availability of effective SARS-CoV-2 vaccines is a large step forward in managing the pandemic situation. In addition, therapeutic options, e.g., monoclonal antibodies to prevent viral cell entry and anti-inflammatory therapies, including glucocorticoid treatment, are currently developed or in clinical use to treat already infected patients. Here, we report a novel dual-specificity inhibitor to simultaneously target SARS-CoV-2 infection and virus-induced hyperinflammation. This was achieved by fusing an inhibitor of viral cell entry with a molecule blocking IL-6, a key mediator of SARS-CoV-2-induced hyperinflammation. Through this dual action, this molecule may have the potential to efficiently ameliorate symptoms of COVID-19 in infected individuals.

Integrative Multi-omics Landscape of Non-structural Protein 3 of Severe Acute Respiratory Syndrome Coronaviruses

The coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is currently a global pandemic. Extensive investigations have been performed to study the clinical and cellular effects of SARS-CoV-2 infection. Mass spectrometry-based proteomics studies have revealed the cellular changes due to the infection and identified a plethora of interactors for all SARS-CoV-2 components, except for the longest non-structural protein 3 (NSP3). Here, we expressed the full-length NSP3 proteins of SARS-CoV and SARS-CoV-2 to investigate their unique and shared functions using multi-omics methods. We conducted interactome, phosphoproteome, ubiquitylome, transcriptome, and proteome analyses of NSP3-expressing cells. We found that NSP3 plays essential roles in cellular functions such as RNA metabolism and immune response (e.g., NF-κB signal transduction). Interestingly, we showed that SARS-CoV-2 NSP3 has both endoplasmic reticulum and mitochondrial localizations. In addition, SARS-CoV-2 NSP3 is more closely related to mitochondrial ribosomal proteins, whereas SARS-CoV NSP3 is related to the cytosolic ribosomal proteins. In summary, our integrative multi-omics study of NSP3 improves the understanding of the functions of NSP3 and offers potential targets for the development of anti-SARS strategies.

De novo ssRNA Aptamers against the SARS-CoV-2 Main Protease: In Silico Design and Molecular Dynamics Simulation

Herein, we have generated ssRNA aptamers to inhibit SARS-CoV-2 M^pro, a protease necessary for the SARS-CoV-2 coronavirus replication. Because there is no aptamer 3D structure currently available in the databanks for this protein, first, we modeled an ssRNA aptamer using an entropic fragment-based strategy. We refined the initial sequence and 3D structure by using two sequential approaches, consisting of an elitist genetic algorithm and an RNA inverse process. We identified three specific aptamers against SARS-CoV-2 M^pro, called MApta^pro, MApta^pro-IR1, and MApta^pro-IR2, with similar 3D conformations and that fall in the dimerization region of the SARS-CoV-2 M^pro necessary for the enzymatic activity. Through the molecular dynamic simulation and binding free energy calculation, the interaction between the MApta^pro-IR1 aptamer and the SARS-CoV-2 M^pro enzyme resulted in the strongest and the highest stable complex; therefore, the ssRNA MApta^pro-IR1 aptamer was selected as the best potential candidate for the inhibition of SARS-CoV-2 M^pro and a perspective therapeutic drug for the COVID-19 disease.