Elucidating the molecular physiopathology of acute respiratory distress syndrome in severe acute respiratory syndrome patients

miR-206 alleviates LPS-induced inflammatory injury in cardiomyocytes via directly targeting USP33 to inhibit the JAK2/STAT3 signaling pathway

Previous reports have confirmed that miR-206 participates in inflammatory cardiomyopathy, but its definite mechanism remains elusive. This study aims to elucidate the potential mechanism of miR-206 in septic cardiomyopathy (SCM). The primary mouse cardiomyocytes were isolated and exposed to lipopolysaccharides (LPS) to construct a septic injury model in vitro. Then, the gene transcripts and protein levels were detected by RT-qPCR and/or Western blot assay. Cell proliferation, apoptosis, and inflammatory responses were evaluated by CCK-8/EdU, flow cytometry, and ELISA assays, respectively. Dual luciferase assay, Co-IP, and ubiquitination experiments were carried out to validate the molecular interactions among miR-206, USP33, and JAK2/STAT3 signaling. miR-206 was significantly downregulated, but USP33 was upregulated in LPS-induced cardiomyocytes. Gain-of-function of miR-206 elevated the proliferation but suppressed the inflammatory responses and apoptosis in LPS-induced cardiomyocytes. USP33, as a member of the USP protein family, was confirmed to be a direct target of miR-206 and could catalyze deubiquitination of JAK2 to activate JAK2/STAT3 signaling. Rescue experiments presented that neither upregulation of USP33 nor JAK2/STAT3 signaling activation considerably reversed the protective effects of miR-206 upregulation in LPS-induced cardiomyocytes. The above data showed that miR-206 protected cardiomyocytes from LPS-induced inflammatory injuries by targeting the USP33/JAK2/STAT3 signaling pathway, which might be a novel target for SCM treatment.

Comparative transcriptome analysis of SARS-CoV-2, SARS-CoV, MERS-CoV, and HCoV-229E identifying potential IFN/ISGs targets for inhibiting virus replication

Introduction

Since its outbreak in December 2019, SARS-CoV-2 has spread rapidly across the world, posing significant threats and challenges to global public health. SARS-CoV-2, together with SARS-CoV and MERS-CoV, is a highly pathogenic coronavirus that contributes to fatal pneumonia. Understanding the similarities and differences at the transcriptome level between SARS-CoV-2, SARS-CoV, as well as MERS-CoV is critical for developing effective strategies against these viruses.

Methods

In this article, we comparatively analyzed publicly available transcriptome data of human cell lines infected with highly pathogenic SARS-CoV-2, SARS-CoV, MERS-CoV, and lowly pathogenic HCoV-229E. The host gene expression profiles during human coronavirus (HCoV) infections were generated, and the pathways and biological functions involved in immune responses, antiviral efficacy, and organ damage were intensively elucidated.

Results

Our results indicated that SARS-CoV-2 induced a stronger immune response versus the other two highly pathogenic HCoVs. Specifically, SARS-CoV-2 induced robust type I and type III IFN responses, marked by higher upregulation of type I and type III IFNs, as well as numerous interferon-stimulated genes (ISGs). Further Ingenuity Pathway Analysis (IPA) revealed the important role of ISGs for impeding SARS-CoV-2 infection, and the interferon/ISGs could be potential targets for therapeutic interventions. Moreover, our results uncovered that SARS-CoV-2 infection was linked to an enhanced risk of multi-organ toxicity in contrast to the other two highly pathogenic HCoVs.

Discussion

These findings provided valuable insights into the pathogenic mechanism of SARS-CoV-2, which showed a similar pathological feature but a lower fatality rate compared to SARS-CoV and MERS-CoV.

An important call: Suggestion of using IL-10 as therapeutic agent for COVID-19 with ARDS and other complications

The global coronavirus disease 2019 (COVID-19) pandemic has a detrimental impact on public health. COVID-19 usually manifests as pneumonia, which can progress into acute respiratory distress syndrome (ARDS) related to uncontrolled TH17 immune reaction. Currently, there is no effective therapeutic agent to manage COVID-19 with complications. The currently available anti-viral drug remdesivir has an effectiveness of 30% in SARS-CoV-2-induced severe complications. Thus, there is a need to identify effective agents to treat COVID-19 and the associated acute lung injury and other complications. The host immunological pathway against this virus typically involves the THαβ immune response. THαβ immunity is triggered by type 1 interferon and interleukin-27 (IL-27), and the main effector cells of the THαβ immune response are IL10-CD4 T cells, CD8 T cells, NK cells, and IgG1-producing B cells. In particular, IL-10 exerts a potent immunomodulatory or anti-inflammatory effect and is an anti-fibrotic agent for pulmonary fibrosis. Concurrently, IL-10 can ameliorate acute lung injury or ARDS, especially those caused by viruses. Owing to its anti-viral activity and anti-pro-inflammatory effects, in this review, IL-10 is suggested as a possible treatment agent for COVID-19.

Drawing Parallels between SARS, MERS, and COVID-19: A Comparative Overview of Epidemiology, Pathogenesis, and Pathological Features

Background

Since November 2019, when the novel coronavirus arose in Wuhan City, over 188 million people worldwide have been infected with COVID-19. It is the third coronavirus outbreak in the twenty-first century. Until now, practically all coronavirus epidemics have occurred due to zoonotic spread from an animal or transitional host or through the consumption of their products. Coronaviruses can infect humans and cause severe illness and even death.

Material and Methods

This review was designed to help us recognize and harmonize the similarities and differences between these three coronaviridae family members.

Result

Measures aimed at containing the epidemic should be emphasized in this circumstance. Prioritizing and planning these activities require an understanding of the particulars of these three viruses. Given the pandemic's enormous death toll and rapid spread, we should be cognizant of the parallels and differences between these three viruses. Additionally, this pandemic warns us to be cautious against the possibility of a future pandemic.

Conclusion

We highlight the fundamental characteristics of coronaviruses that are critical for recognizing coronavirus epidemiology, pathogenesis, and pathological features that reveal numerous significant pathological attributes and evolutionary patterns in the viral genome that aid in better understanding and anticipating future epidemics.

The roles of critical pro-inflammatory cytokines in the drive of cytokine storm during SARS-CoV-2 infection

In patients with severe COVID-19, acute respiratory distress syndrome (ARDS), multiple organ dysfunction syndrome (MODS), and even mortality can result from cytokine storm, which is a hyperinflammatory medical condition caused by the excessive and uncontrolled release of pro-inflammatory cytokines. High levels of numerous crucial pro-inflammatory cytokines, such as interleukin-1 (IL-1), IL-2, IL-6, tumor necrosis factor-α, interferon (IFN)-γ, IFN-induced protein 10 kDa, granulocyte-macrophage colony-stimulating factor, monocyte chemoattractant protein-1, and IL-10 and so on, have been found in severe COVID-19. They participate in cascade amplification pathways of pro-inflammatory responses through complex inflammatory networks. Here, we review the involvements of these critical inflammatory cytokines in SARS-CoV-2 infection and discuss their potential roles in triggering or regulating cytokine storm, which can help to understand the pathogenesis of severe COVID-19. So far, there is rarely effective therapeutic strategy for patients with cytokine storm besides using glucocorticoids, which is proved to result in fatal side effects. Clarifying the roles of key involved cytokines in the complex inflammatory network of cytokine storm will help to develop an ideal therapeutic intervention, such as neutralizing antibody of certain cytokine or inhibitor of some inflammatory signal pathways.

Human ACE-2, MCP1 and micro-RNA 146 as Novel Markers for COVID- 19 Affection and Severity

BACKGROUND & AIMS

Coronavirus disease - 2019 (COVID-19) is a major pandemic that causes high morbidity and mortality rates.

AIM OF THIS STUDY

to detect the relations between many risk factors, ACE-2, MCP-1, Micro RNA 146 gene expression, and COVID-19 infection and disease severity.

METHODS

This study was carried out on 165 cases of COVID-19 and 138 controls. ACE2 and MCP1 levels were measured in COVID-19 cases and control by ELISA and micro-RNA-146 expression by PCR.

RESULTS

We found an increased blood level of ACE2 and MCP1 in COVID- 19 patients than in healthy persons and a significant down-regulation of micro-RNA 146 gene expression in cases than in controls. There was a significant correlation between increased blood level of ACE2, regulation of micro-RNA 146 gene expression and severity of lung affection, a significant correlation was found between increased blood level of MCP1 and thrombosis in COVID-19 patients. Neurological complications were significantly correlated with more viral load, more ACE2 blood level, and down regulation of micro RNA146 expression.

CONCLUSION

High viral load, increased blood level of ACE2, and down-regulation of micro-RNA 146 expression are associated with more severe lung injury and the presence of neurologic complications like convulsions and coma in COVID-19 Egyptian patients.

Antigen-Specific T Cells and SARS-CoV-2 Infection: Current Approaches and Future Possibilities

COVID-19, a significant global health threat, appears to be an immune-related disease. Failure of effective immune responses in initial stages of infection may contribute to development of cytokine storm and systemic inflammation with organ damage, leading to poor clinical outcomes. Disease severity and the emergence of new SARS-CoV-2 variants highlight the need for new preventative and therapeutic strategies to protect the immunocompromised population. Available data indicate that these people may benefit from adoptive transfer of allogeneic SARS-CoV-2-specific T cells isolated from convalescent individuals. This review first provides an insight into the mechanism of cytokine storm development, as it is directly related to the exhaustion of T cell population, essential for viral clearance and long-term antiviral immunity. Next, we describe virus-specific T lymphocytes as a promising and efficient approach for the treatment and prevention of severe COVID-19. Furthermore, other potential cell-based therapies, including natural killer cells, regulatory T cells and mesenchymal stem cells are mentioned. Additionally, we discuss fast and effective ways of producing clinical-grade antigen-specific T cells which can be cryopreserved and serve as an effective "off-the-shelf" approach for rapid treatment of SARS-CoV-2 infection in case of sudden patient deterioration.

Comparative highlights on MERS-CoV, SARS-CoV-1, SARS-CoV-2, and NEO-CoV

The severe acute respiratory syndrome (SARS-CoV, now SARS-CoV-1), middle east respiratory syndrome (MERS-CoV), Neo-CoV, and 2019 novel coronavirus (SARS-CoV-2/COVID-19) are the most notable coronaviruses, infecting the number of people worldwide by targeting the respiratory system. All these viruses are of zoonotic origin, predominantly from bats which are one of the natural reservoir hosts for coronaviruses. Thus, the major goal of our review article is to compare and contrast the characteristics and attributes of these coronaviruses. The SARS-CoV-1, MERS-CoV, and COVID-19 have many viral similarities due to their classification, they are not genetically related. COVID-19 shares approximately 79 % of its genome with SARS-CoV-1 and about 50 % with MERS-CoV. The shared receptor protein, ACE2 exhibit the most striking genetic similarities between SARS-CoV-1 and SARS-CoV-2. SARS-CoV primarily replicates in the epithelial cells of the respiratory system, but it may also affect macrophages, monocytes, activated T cells, and dendritic cells. MERS-CoV not only infects and replicates inside the epithelial and immune cells, but it may lyse them too, which is one of the common reasons for MERS's higher mortality rate. The details of infections caused by SARS-CoV-2 and lytic replication mechanisms in host cells are currently mysterious. In this review article, we will discuss the comparative highlights of SARS-CoV-1, MERS-CoV, SARS-CoV-2, and Neo-CoV, concerning their structural features, morphological characteristics, sources of virus origin and their evolutionary transitions, infection mechanism, computational study approaches, pathogenesis and their severity towards several diseases, possible therapeutic approaches, and preventive measures.

Ventilation strategies to reduce airborne transmission of viruses in classrooms: A systematic review of scientific literature

The recent pandemic due to SARS-CoV-2 has brought to light the need for strategies to mitigate contagion between human beings. Apart from hygiene measures and social distancing, air ventilation highly prevents airborne transmission within enclosed spaces. Among others, educational environments become critical in strategic planning to control the spread of pathogens and viruses amongst the population, mainly in cold conditions. In the event of a virus outbreak - such as COVID or influenza - many school classrooms still lack the means to guarantee secure and healthy environments. The present review examines school contexts that implement air ventilation strategies to reduce the risk of contagion between students. The analysed articles present past experiences that use either natural or mechanical systems assessed through mathematical models, numerical models, or full-scale experiments. For naturally ventilated classrooms, the studies highlight the importance of the architectural design of educational spaces and propose strategies for aeration control such as CO₂-based control and risk-infection control. When it comes to implementing mechanical ventilation in classrooms, different systems with different airflow patterns are assessed based on their ability to remove airborne pathogens considering parameters like the age of air and the generation of airflow streamlines. Moreover, studies report that programmed mechanical ventilation systems can reduce risk-infection during pandemic events. In addition to providing a systematic picture of scientific studies in the field, the findings of this review can be a valuable reference for school administrators and policymakers to implement the best strategies in their classroom settings towards reducing infection risks.

Proteomic Analysis Reveals Differential Expression Profiles in Idiopathic Pulmonary Fibrosis Cell Lines

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, irreversible lung disorder of unknown cause. This disease is characterized by profibrotic activation of resident pulmonary fibroblasts resulting in aberrant deposition of extracellular matrix (ECM) proteins. However, although much is known about the pathophysiology of IPF, the cellular and molecular processes that occur and allow aberrant fibroblast activation remain an unmet need. To explore the differentially expressed proteins (DEPs) associated with aberrant activation of these fibroblasts, we used the IPF lung fibroblast cell lines LL97A (IPF-1) and LL29 (IPF-2), compared to the normal lung fibroblast cell line CCD19Lu (NL-1). Protein samples were quantified and identified using a label-free quantitative proteomic analysis approach by liquid chromatography-tandem mass spectrometry (LC-MS/MS). DEPs were identified after pairwise comparison, including all experimental groups. Gene Ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Protein–Protein Interaction (PPI) network construction were used to interpret the proteomic data. Eighty proteins expressed exclusively in the IPF-1 and IPF-2 clusters were identified. In addition, 19 proteins were identified up-regulated in IPF-1 and 10 in IPF-2; 10 proteins were down-regulated in IPF-1 and 2 in IPF-2 when compared to the NL-1 proteome. Using the search tool for retrieval of interacting genes/proteins (STRING) software, a PPI network was constructed between the DEPs and the 80 proteins expressed exclusively in the IPF-2 and IPF-1 clusters, containing 115 nodes and 136 edges. The 10 hub proteins present in the IPP network were identified using the CytoHubba plugin of the Cytoscape software. GO and KEGG pathway analyses showed that the hub proteins were mainly related to cell adhesion, integrin binding, and hematopoietic cell lineage. Our results provide relevant information on DEPs present in IPF lung fibroblast cell lines when compared to the normal lung fibroblast cell line that could play a key role during IPF pathogenesis.

The Role of Cytokines and Chemokines in Severe Acute Respiratory Syndrome Coronavirus 2 Infections

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in countless infections and caused millions of deaths since its emergence in 2019. Coronavirus disease 2019 (COVID-19)-associated mortality is caused by uncontrolled inflammation, aberrant immune response, cytokine storm, and an imbalanced hyperactive immune system. The cytokine storm further results in multiple organ failure and lung immunopathology. Therefore, any potential treatments should focus on the direct elimination of viral particles, prevention strategies, and mitigation of the imbalanced (hyperactive) immune system. This review focuses on cytokine secretions of innate and adaptive immune responses against COVID-19, including interleukins, interferons, tumor necrosis factor-alpha, and other chemokines. In addition to the review focus, we discuss potential immunotherapeutic approaches based on relevant pathophysiological features, the systemic immune response against SARS-CoV-2, and data from recent clinical trials and experiments on the COVID-19-associated cytokine storm. Prompt use of these cytokines as diagnostic markers and aggressive prevention and management of the cytokine storm can help determine COVID-19-associated morbidity and mortality. The prophylaxis and rapid management of the cytokine storm appear to significantly improve disease outcomes. For these reasons, this study aims to provide advanced information to facilitate innovative strategies to survive in the COVID-19 pandemic.

Polysalicylic Acid Polymer Microparticle Decoys Therapeutically Treat Acute Respiratory Distress Syndrome

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) remain problematic due to high mortality rates and lack of effective treatments. Neutrophilic injury contributes to mortality in ALI/ARDS. Here, technology for rapid ARDS intervention is developed and evaluated, where intravenous salicylic acid-based polymer microparticles, i.e., Poly-Aspirin (Poly-A), interfere with neutrophils in blood, reducing lung neutrophil infiltration and injury in vivo in mouse models of ALI/ARDS. Importantly, Poly-A particles reduce multiple inflammatory cytokines in the airway and bacterial load in the bloodstream in a live bacteria lung infection model of ARDS, drastically improving survival. It is observed that phagocytosis of the Poly-A microparticles, with salicylic acid in the polymer backbone, alters the neutrophil surface expression of adhesion molecules, potentially contributing to their added therapeutic benefits. Given the proven safety profile of the microparticle degradation products-salicylic acid and adipic acid-it is anticipated that the Poly-A particles represent a therapeutic strategy in ARDS with a rare opportunity for rapid clinical translation.

Expression of Macrophage Scavenger Receptor (MSR1) in Peripheral Blood Cells from Patients with Different Respiratory Diseases: Beyond Monocytes

Background: Macrophage scavenger receptor 1 (MSR1) has mostly been described in macrophages, but we previously found a significant gene expression increase in peripheral blood mononuclear cells (PBMCs) of asthmatic patients. Objective: To confirm those results and to define its cellular origin in PBMCs. Methods: Four groups of subjects were studied: healthy controls (C), nonallergic asthmatic (NA), allergic asthmatic (AA), and chronic obstructive pulmonary disease (COPD) patients. RNA was extracted from PBMCs. MSR1 gene expression was analyzed by RT-qPCR. The presence of MSR1 on the cellular surface of PBMC cellular subtypes was analyzed by confocal microscopy and flow cytometry. Results: MSR1 gene expression was significantly increased in the three clinical conditions compared to the healthy control group, with substantial variations according to disease type and severity. MSR1 expression on T cells (CD4⁺ and CD8⁺), B cells, and monocytes was confirmed by confocal microscopy and flow cytometry. In all clinical groups, the four immune cell subtypes studied expressed MSR1, with a greater expression on B lymphocytes and monocytes, exhibiting differences according to disease and severity. Conclusions: This is the first description of MSR1’s presence on lymphocytes’ surfaces and reinforces the potential role of MSR1 as a player in asthma and COPD.

Abnormal liver chemistries as a predictor of COVID-19 severity and clinical outcomes in hospitalized patients

BACKGROUND

Abnormal liver chemistries are common findings in patients with Coronavirus Disease 2019 (COVID-19). However, the association of these abnormalities with the severity of COVID-19 and clinical outcomes is poorly understood

AIM

We aimed to assess the prevalence of elevated liver chemistries in hospitalized patients with COVID-19 and compare the serum liver chemistries to predict the severity and in-hospital mortality.

METHODS

This retrospective, observational study included 3380 patients with COVID-19 who were hospitalized in the Johns Hopkins Health System (Baltimore, MD, United States). Demographic data, clinical characteristics, laboratory findings, treatment measures, and outcome data were collected. Cox regression modeling was used to explore variables associated with abnormal liver chemistries on admission with disease severity and prognosis

RESULTS

A total of 2698 (70.4%) had abnormal alanine aminotransferase (ALT) at the time of admission. Other more prevalent abnormal liver chemistries were aspartate aminotransferase (AST) (44.4%), alkaline phosphatase (ALP) (16.1%), and total bilirubin (T-Bil) (5.9%). Factors associated with liver injury were older age, Asian ethnicity, other race, being overweight, and obesity. Higher ALT, AST, T-Bil, and ALP levels were more commonly associated with disease severity. Multivariable adjusted Cox regression analysis revealed that abnormal AST and T-Bil were associated with the highest mortality risk than other liver injury indicators during hospitalization. Abnormal AST, T-Bil, and ALP were associated with a need for vasopressor drugs, whereas higher levels of AST, T-Bil, and a decreased albumin levels were associated with mechanical ventilation

CONCLUSION

Abnormal liver chemistries are common at the time of hospital admission in COVID-19 patients and can be closely related to the patient’s severity and prognosis. Elevated liver chemistries, specifically ALT, AST, ALP, and T-Bil levels, can be used to stratify risk and predict the need for advanced therapies in these patients.

Severe versus common COVID-19: an early warning nomogram model

The wide spread of coronavirus disease 2019 is currently the most rigorous health threat, and the clinical outcomes of severe patients are extremely poor. In this study, we establish an early warning nomogram model related to severe versus common COVID-19. A total of 1059 COVID-19 patients were analyzed in the primary cohort and divided into common and severe according to the guidelines on the Diagnosis and Treatment of COVID-19 by the National Health Commission of China (7th version). The clinical data were collected for logistic regression analysis to assess the risk factors for severe versus common type. Furthermore, 123 COVID-19 patients were reviewed as the validation cohort to assess the performance of this model. Multivariate logistic analysis revealed that age, dyspnea, lymphocyte count, C-reactive protein and interleukin-6 were independent factors for prewarning the severe type occurrence. Then, the early warning nomogram model including these risk factors for inferring the severe disease occurrence out of common type of COVID-19 was constructed. The C-index of this nomogram in the primary cohort was 0.863, 95% confidence interval (CI) (0.836-0.889). Meanwhile, in the validation cohort, the C-index of this nomogram was 0.889, 95% CI (0.828-0.950). In both the primary cohort and validation cohorts, the calibration curve showed good agreement between prediction and actual probability. The early warning model shows that data at the very beginning including age, dyspnea, lymphocyte count, CRP, and IL-6 may prewarn the severe disease occurrence to some extent, which could help clinicians early and timely treatment.

Comprehensive Flow Cytometry Profiling of the Immune System in COVID-19 Convalescent Individuals

SARS-CoV-2 has infected more than 200 million people worldwide, with more than 4 million associated deaths. Although more than 80% of infected people develop asymptomatic or mild COVID-19, SARS-CoV-2 can induce a profound dysregulation of the immune system. Therefore, it is important to investigate whether clinically recovered individuals present immune sequelae. The potential presence of a long-term dysregulation of the immune system could constitute a risk factor for re-infection and the development of other pathologies. Here, we performed a deep analysis of the immune system in 35 COVID-19 recovered individuals previously infected with SARS-CoV-2 compared to 16 healthy donors, by flow cytometry. Samples from COVID-19 individuals were analysed from 12 days to 305 days post-infection. We observed that, 10 months post-infection, recovered COVID-19 patients presented alterations in the values of some T-cell, B-cell, and innate cell subsets compared to healthy controls. Moreover, we found in recovered COVID-19 individuals increased levels of circulating follicular helper type 1 (cTfh1), plasmablast/plasma cells, and follicular dendritic cells (foDC), which could indicate that the Tfh-B-foDC axis might be functional to produce specific immunoglobulins 10 months post-infection. The presence of this axis and the immune system alterations could constitute prognosis markers and could play an important role in potential re-infection or the presence of long-term symptoms in some individuals.

High Levels of Circulating IL-6 and IL-8 Signature can Predict COVID-19 Severity

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection may trigger a cytokine storm, which is characterized by uncontrolled overproduction of proinflammatory cytokines. Objectives: We aimed to investigate the association between circulating levels of inflammatory cytokines and severity of coronavirus disease 2019 (COVID-19). Methods: This cross-sectional study included 46 severe and 32 mildly symptomatic COVID-19 patients. The serum levels of cytokines and chemokines were determined using the Bio-Plex ProTM Human Cytokine Screening Panel. Results: Out of a total of 78 patients with confirmed COVID-19, 54 (69.2%) were males, and 24 (30.8%) were females. The mean age was 43.1 ± 13.3 and 58.2 ± 15 in mild and severe patients, respectively. Severe patients were characterized by significant laboratory abnormalities, such as increased WBC (P = 0.002) and neutrophil counts (P = 0.001), higher levels of ALT (P = 0.03), AST (P = 0.002), LDH (P < 0.001), urea (P = 0.013), ferritin (P < 0.001), D-dimer (P = 0.042), CRP (P < 0.001), and decreased lymphocyte (P < 0.001) and platelet (P = 0.045) counts. The levels of IL-6, IL-8, IL-13, TNF-α, IFN-γ, MIP-1β, and MCP-1 increased in the severe group compared to the mild group. However, significant differences were observed only for IL-6 (P < 0.001) and IL-8 (P < 0.001) levels. Conclusions: Serum IL-6 and IL-8 levels can be used as potential prognostic biomarkers of disease severity in COVID-19 patients.

Molecular mechanisms of lidocaine

Lidocaine is an amide-class local anesthetic used clinically to inhibit pain sensations. Systemic administration of lidocaine has antinociceptive, antiarrhythmic, anti-inflammatory, and antithrombotic effects. Lidocaine exerts these effects under both acute and chronic pain conditions and acute respiratory distress syndrome through mechanisms that can be independent of its primary mechanism of action, sodium channel inhibition. Here we review the pathophysiological underpinnings of lidocaine's role as an anti-nociceptive, anti-inflammatory mediated by toll-like receptor (TLR) and nuclear factor kappa-β (NF-kβ) signalling pathways and downstream cytokine effectors high mobility group box 1 (HMGB1) and tumour necrosis factor-α (TNF-α).

Immune Intervention in Sepsis

Sepsis is a host immune disorder induced by infection. It can lead to multiple organ dysfunction syndrome (MODS), which has high morbidity and mortality. There has been great progress in the clinical diagnosis and treatment of sepsis, such as improvements in pathogen detection technology, innovations regarding anti-infection drugs, and the development of organ function support. Abnormal immune responses triggered by pathogens, ranging from excessive inflammation to immunosuppression, are recognized to be an important cause of the high mortality rate. However, no drugs have been approved specifically for treating sepsis. Here, we review the recent research progress on immune responses in sepsis to provide a theoretical basis for the treatment of sepsis. Constructing and optimizing a dynamic immune system treatment regimen based on anti-infection treatment, fluid replacement, organ function support, and timely use of immunomodulatory interventions may improve the prognosis of sepsis patients.

Pathological diagnosis of Coronavirus-related nephropathy: insight from postmortem studies

A novel coronavirus pneumonia first occurred in Wuhan, China in early December 2019; the causative agent was identified and named as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by the World Health Organization (WHO), and the resulting disease termed coronavirus disease 2019 (COVID-19), according to the WHO coronavirus disease situation reports. This condition has spread rapidly all over the world and caused more than 125 million cases globally, with more than 2 million related deaths. Two previous outbreaks due to zoonotic coronaviruses have occurred in the last 20 years, namely the severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV), causing high morbidity and mortality in human populations upon crossing the species barriers. SARS-CoV-2, SARS-CoV, and MERS-CoV show several similarities in pathogenicity and clinical presentations, the latter ranging from asymptomatic infection to severe acute respiratory distress syndrome (ARDS) and multiorgan impairment. Acute kidney injury (AKI) has been commonly reported in patients with CoV infections; therefore, pathological analysis of renal parenchyma in these patients has been carried out in order to improve knowledge about underlying mechanisms. Viral infection has been demonstrated in the renal tubular epithelial cells by electron microscopy (EM), immunohistochemistry (IHC), and in situ hybridization (ISH), although with conflicting results. Light microscopy (LM) changes have been described in the renal parenchyma primarily in the form of acute renal tubular damage, possibly due to direct viral cytopathic effect and immune-mediated mechanisms such as cytokine storm syndrome. In this review, we describe and discuss the spectrum of histological, ultrastructural, and molecular findings in SARS-CoV, MERS-CoV, and SARS-CoV-2-related renal pathology obtained from postmortem studies, as well as intrinsic limitations and pitfalls of current diagnostic techniques.

Aberrant cytokine expression in COVID-19 patients: Associations between cytokines and disease severity

Cytokines play pleiotropic, antagonistic, and collaborative in viral disease. The high morbidity and mortality of coronavirus disease 2019 (COVID-19) make it a significant threat to global public health. Elucidating its pathogenesis is essential to finding effective therapy. A retrospective study was conducted on 71 patients hospitalized with COVID-19. Data on cytokines, T lymphocytes, and other clinical and laboratory characteristics were collected from patients with variable disease severity. The effects of cytokines on the overall survival (OS) and event-free survival (EFS) of patients were analyzed. The critically severe and severe patients had higher infection indexes and significant multiple organ function abnormalities than the mild patients (P < 0.05). IL-6 and IL-10 were significantly higher in the critically severe patients than in the severe and mild patients (P < 0.05). IL-6 and IL-10 were closely associated with white blood cells, neutrophils, T lymphocyte subsets, D-D dimer, blood urea nitrogen, complement C1q, procalcitonin C-reactive protein. Moreover, the IL-6 and IL-10 levels were closely correlated to dyspnea and dizziness (P < 0.05). The patients with higher IL-10 levels had shorter OS than the group with lower levels (P < 0.05). The older patients with higher levels of single IL-6 or IL-10 tended to have shorter EFS (P < 0.05), while the patients who had more elevated IL-6 and IL-10 had shorter OS (P < 0.05). The Cox proportional hazard model revealed that IL-6 was the independent factor affecting EFS. IL-6 and IL-10 play crucial roles in COVID-19 prognosis.

The next generation of HCV vaccines: a focus on novel adjuvant development

INTRODUCTION

Considerable efforts have been made to treat and prevent acute and chronic infections caused by the hepatitis C virus (HCV). Current treatments are unable to protect people from reinfection. Hence, there is a need for development of both preventive and therapeutic HCV vaccines. Many vaccine candidates are in development to fight against HCV, but their efficacy has so far proven limited partly due to low immunogenicity.

AREAS COVERED

We explore development of novel and powerful adjuvants to achieve an effective HCV vaccine. The basis for developing strong adjuvants is to understand the innate immunity pathway, which subsequently stimulates humoral and cellular immune responses. We have also investigated immunogenicity of developed adjuvants that have been used in recent studies available in online databases such as PubMed, PMC, ScienceDirect, Google Scholar, etc.

EXPERT OPINION

Adjuvants are used as a part of vaccine formulation to boost vaccine immunogenicity and antigen delivery. Several FDA-approved adjuvants are used in licensed human vaccines. Unfortunately, no adjuvant has yet been proven to boost HCV immune responses to the extent needed for an effective vaccine. One of the promising approaches for developing an effective adjuvant is the combination of various adjuvants to trigger several innate immune responses, leading to activation of adaptive immunity.[Figure: see text].

Role of toll-like receptor 7/8 pathways in regulation of interferon response and inflammatory mediators during SARS-CoV2 infection and potential therapeutic options

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2) is the causative agent of Corona Virus Disease 2019 (COVID-19). Lower production of type I and III interferons and higher levels of inflammatory mediators upon SARS-CoV2 infection contribute to COVID-19 pathogenesis. Optimal interferon production and controlled inflammation are essential to limit COVID-19 pathogenesis. However, the aggravated inflammatory response observed in COVID-19 patients causes severe damage to the host and frequently advances to acute respiratory distress syndrome (ARDS). Toll-like receptor 7 and 8 (TLR7/8) signaling pathways play a central role in regulating induction of interferons (IFNs) and inflammatory mediators in dendritic cells. Controlled inflammation is possible through regulation of TLR mediated response without influencing interferon production to reduce COVID-19 pathogenesis. This review focuses on inflammatory mediators that contribute to pathogenic effects and the role of TLR pathways in the induction of interferon and inflammatory mediators and their contribution to COVID-19 pathogenesis. We conclude that potential TLR7/8 agonists inducing antiviral interferon response and controlling inflammation are important therapeutic options to effectively eliminate SARS-CoV2 induced pathogenesis. Ongoing and future studies may provide additional evidence on their safety and efficacy to treat COVID-19 pathogenesis.

Mouthrinses against SARS-CoV-2: anti-inflammatory effectivity and a clinical pilot study

Purpose

The scope of this research endeavor was the determination of the applicability of over the counter mouthwash solutions in reducing the viral load in the saliva of COVID-19 patients and hence decreasing their infectivity. Beyond that, new experimental mouthwashes were investigated in terms of a possible positive immune modulation, which might offer an additional opportunity for a positive pharmaceutical effect.

Methods

The effectivity of the mouth washing solution was determined on 34 hospitalized COVID-19 patients by measuring the viral load by RT-qPCR in pharyngeal swabs, which were taken before and after rinsing. The inflammatory modulation thru the experimental solutions was assayed in an in vitro model of virus infected nasopharyngeal epithelium cells.

Results

The clinical pilot study demonstrated that the mouth rinsing solution was able to reduce the viral load by about 90% in the saliva of most patients. This reduction was determined to persist for about 6 h. In the experimental solutions, the ingredients dexpanthenol and zinc were able to reduce the expression of proinflammatory cytokines in the cell culture model, while the antiviral response was not altered significantly.

Conclusion

We recommend the application of mouth wash solutions to COVID-19 patients, since our results indicate a reduction in infectivity and might govern the protection of health care professionals. Further improvement to the over the counter formulation can be made by utilizing zinc and dexpanthenol, as they which might be beneficial for the patients’ health.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00405-021-06873-8.

SARS-CoV-2 and other human coronavirus show genome patterns previously associated to reduced viral recognition and altered immune response

A new pandemic caused by the betacoronavirus SARS-CoV-2 originated in China in late 2019. Although often asymptomatic, a relevant percentage of affected people can develop severe pneumonia. Initial evidence suggests that dysregulation of the immune response could contribute to the pathogenesis, as previously demonstrated for SARS-CoV. The presence of genome composition features involved in delaying viral recognition is herein investigated for human coronaviruses (HCoVs), with a special emphasis on SARS-CoV-2. A broad collection of HCoVs polyprotein, envelope, matrix, nucleocapsid and spike coding sequences was downloaded and several statistics representative of genome composition and codon bias were investigated. A model able to evaluate and test the presence of a significant under- or over-representation of dinucleotide pairs while accounting for the underlying codon bias and protein sequence was also implemented. The study revealed the significant under-representation of CpG dinucleotide pair in all HcoV, but especially in SARS-CoV and even more in SARS-CoV-2. The presence of forces acting to minimize CpG content was confirmed by relative synonymous codon usage pattern. Codons containing the CpG pair were severely under-represented, primarily in the polyprotein and spike coding sequences of SARS-CoV-2. Additionally, a significant under-representation of the TpA pair was observed in the N and S region of SARS-CoV and SARS-CoV-2. Increasing experimental evidence has proven that CpG and TpA are targeted by innate antiviral host defences, contributing both to RNA degradation and RIG-1 mediated interferon production. The low content of these dinucleotides could contribute to a delayed interferon production, dysregulated immune response, higher viral replication and poor outcome. Significantly, the RIG-1 signalling pathway was proven to be defective in elderlies, suggesting a likely interaction between limited viral recognition and lower responsiveness in interferon production that could justify the higher disease severity and mortality in older patients.

Coronavirus disease 2019, allergic diseases, and allergen immunotherapy: Possible favorable mechanisms of interaction

Background: Both, allergen immunotherapy (AIT) and SARS-COV-2 infection cause a set of immunologic changes that respectively vary during the course of the treatment or the disease. Objective: To review immune changes brought along by each of these entities and how they might interrelate. Methods: We start presenting a brief review of the structure of the new coronavirus and how it alters the functioning of the human immune system. Subsequently, we describe the immune changes induced by AIT and how these changes could be favorable or unfavorable in the allergic patient infected with SARS-CoV-2 at a particular point of time during the evolving infection. Results: We describe how a healthy immune response against SARS-CoV-2 develops, versus an immune response that is initially suppressed by the virus, but ultimately overactivated, leading to an excessive production of cytokines (cytokine-storm-like). These changes are then linked to the clinical manifestations and outcomes of the patient. Reviewing the immune changes secondary to AIT, it becomes clear how AIT is capable of restoring a healthy innate immunity. Investigators have previously shown that the frequency of respiratory infections is reduced in allergic patients treated with AIT. On the other hand it also increases immunoregulation. Conclusion: As there are many variables involved, it is hard to predict how AIT could influence the allergic patient's reaction to a SARS-CoV-2 infection. In any case, AIT is likely to be beneficial for the patient with allergic rhinitis and/or allergic asthma in the context of the SARS-CoV-2 pandemic as controlling allergic diseases leads to a reduced need for contact with healthcare professionals. The authors remind the reader that everything in this article is still theoretical, since at the moment, there are no published clinical trials on the outcome of COVID-19 in allergic patients under AIT.

Autopsy Tool in Unknown Diseases: The Experience with Coronaviruses (SARS-CoV, MERS-CoV, SARS-CoV-2)

In the last two decades, three unknown pathogens have caused outbreaks, generating severe global health concerns. In 2003, after nucleic acid genotyping, a new virus was named severe acute respiratory syndrome coronavirus (SARS-CoV). After nine years, another coronavirus emerged in the middle east and was named MERS-CoV (Middle East Respiratory Syndrome-Coronavirus). Finally, in December 2019, a new unknown coronavirus was isolated from a cluster of patients and was named SARS-CoV-2 (COVID-19, coronavirus disease 2019). This review aims to propose a complete overview of autopsy in the three coronaviruses over the past two decades, showing its pivotal role in the management of unknown diseases. A total of 116 studies fulfilled the inclusion criteria: 14 studies were collected concerning SARS-CoV (87 autopsy reports, from Asian and American countries), 2 studies for MERS-CoV (2 autopsy reports, from Middle-East Asian countries), and 100 studies on SARS-CoV-2 (930 autopsy reports). Analyzing the data obtained on COVID-19, based on the country criterion, a large number of post-mortem investigation were performed in European countries (580 reports), followed by American countries (251 reports). It is interesting to note that no data were found from the Oceanic countries, maybe because of the minor involvement of the outbreak. In all cases, autopsy provided much information about each unknown coronavirus. Despite advanced technologies in the diagnostic fields, to date, autopsy remains the gold standard method to understand the biological features and the pathogenesis of unknown infections, especially when awareness of a pathogen is restricted and the impact on the healthcare system is substantial. The knowledge gained through this technique may positively influence therapeutic strategies, ultimately reducing mortality.

Pathogenetic profiling of COVID-19 and SARS-like viruses

The novel coronavirus (2019-nCoV) has recently emerged, causing COVID-19 outbreaks and significant societal/global disruption. Importantly, COVID-19 infection resembles SARS-like complications. However, the lack of knowledge about the underlying genetic mechanisms of COVID-19 warrants the development of prospective control measures. In this study, we employed whole-genome alignment and digital DNA-DNA hybridization analyses to assess genomic linkage between 2019-nCoV and other coronaviruses. To understand the pathogenetic behavior of 2019-nCoV, we compared gene expression datasets of viral infections closest to 2019-nCoV with four COVID-19 clinical presentations followed by functional enrichment of shared dysregulated genes. Potential chemical antagonists were also identified using protein-chemical interaction analysis. Based on phylogram analysis, the 2019-nCoV was found genetically closest to SARS-CoVs. In addition, we identified 562 upregulated and 738 downregulated genes (adj. P ≤ 0.05) with SARS-CoV infection. Among the dysregulated genes, SARS-CoV shared ≤19 upregulated and ≤22 downregulated genes with each of different COVID-19 complications. Notably, upregulation of BCL6 and PFKFB3 genes was common to SARS-CoV, pneumonia and severe acute respiratory syndrome, while they shared CRIP2, NSG1 and TNFRSF21 genes in downregulation. Besides, 14 genes were common to different SARS-CoV comorbidities that might influence COVID-19 disease. We also observed similarities in pathways that can lead to COVID-19 and SARS-CoV diseases. Finally, protein-chemical interactions suggest cyclosporine, resveratrol and quercetin as promising drug candidates against COVID-19 as well as other SARS-like viral infections. The pathogenetic analyses, along with identified biomarkers, signaling pathways and chemical antagonists, could prove useful for novel drug development in the fight against the current global 2019-nCoV pandemic.

Chemokine Regulation During Epidemic Coronavirus Infection

SARS-CoV-2 (Severe Acute Respiratory Syndrome coronavirus-2) is the third coronavirus to emerge as a cause of severe and frequently fatal pneumonia epidemics in humans, joining SARS-CoV and MERS-CoV (Middle East Respiratory Syndrome-coronavirus). As with many infectious diseases, the immune response to coronavirus infection may act as a double-edged sword: necessary for promoting antiviral host defense, but, if not appropriately regulated, also able to incite life-threatening immunopathology. Key immunoregulatory mediators include the chemokines, a large family of leukocyte chemoattractants that coordinate leukocyte infiltration, positioning and activation in infected tissue by acting at specific G protein-coupled receptors. Here, we compare the involvement of chemokines and chemokine receptors during infection with the three epidemic coronaviruses and discuss their potential value as biomarkers and targets for therapeutic development.

Higher expression of monocyte chemotactic protein 1 in mild COVID-19 patients might be correlated with inhibition of Type I IFN signaling

BACKGROUND

Chemokine levels in severe coronavirus disease 2019 (COVID-19) patients have been shown to be markedly elevated. But the role of chemokines in mild COVID-19 has not yet been established. According to the epidemiological statistics, most of the COVID-19 cases in Shiyan City, China, have been mild. The purpose of this study was to evaluate the level of chemokines in mild COVID-19 patients and explore the correlation between chemokines and host immune response.

METHODS

In this study, we used an enzyme-linked immunosorbent assay to detect serum levels of chemokines in COVID-19 patients in Shiyan City. Expression of chemokine receptors and of other signaling molecules was measured by real-time polymerase chain reaction.

RESULTS

We first demonstrated that COVID-19 patients, both sever and mild cases, are characterized by higher level of chemokines. Specifically, monocyte chemotactic protein 1 (MCP-1) is expressed at higher levels both in severe and mild cases of COVID-19. The receptor of MCP-1, C-C chemokine receptor type 2, was expressed at higher levels in mild COVID-19 patients. Finally, we observed a significant negative correlation between expression levels of interferon (IFN) regulatory factor 3 (IRF3) and serum levels of MCP-1 in mild COVID-19 patients.

CONCLUSION

Higher expression of MCP-1 in mild COVID-19 patients might be correlated with inhibition of IFN signaling. The finding adds to our understanding of the immunopathological mechanisms of severe acute respiratory syndrome coronavirus 2 infection and provides potential therapeutic targets and strategies.

Guanylate-binding protein 1 correlates with advanced tumor features, and serves as a prognostic biomarker for worse survival in lung adenocarcinoma patients

OBJECTIVE

Guanylate-binding protein 1 (GBP1) is reported to promote tumor progression and treatment resistance in lung cancer, and presents as a prognostic biomarker in several solid tumors. However, the related research of GBP1 in clinical management of lung adenocarcinoma is still lacking. Therefore, the present study aimed to detect the clinical role of GBP1 in lung adenocarcinoma.

METHODS

The clinical data of 221 lung adenocarcinoma patients were retrospectively analyzed, and then, their tumor tissue specimens and paired adjacent tissue specimens were retrieved for GBP1 detection via immunohistochemistry (IHC) assay.

RESULTS

GBP1 expression was upregulated in tumor tissues compared with adjacent tissues (P < .001). Moreover, high tumor GBP1 expression was associated with larger tumor size (P = .030), positive lymph node (LYN) metastasis (P = .001), advanced TNM stage (P = .001), and abnormal preoperative carcinoembryonic antigen (CEA) level (P = .026). Furthermore, tumor GBP1 high expression was correlated with reduced disease-free survival (DFS) and overall survival (OS), and was of independent value in predicting worse DFS and OS. Additionally, data analysis of 1144 lung cancer patients derived from KMplot database (www.kmplot.com) further verified that GBP1 expression was negatively correlated with OS (P = .009).

CONCLUSION

GBP1 correlates with advanced tumor features and worse survival profiles, suggesting its value to be a prognostic biomarker in management of lung adenocarcinoma.

Early versus late acute kidney injury among patients with COVID-19-a multicenter study from Wuhan, China

BACKGROUND

Acute kidney injury (AKI) is an important complication of coronavirus disease 2019 (COVID-19), which could be caused by both systematic responses from multi-organ dysfunction and direct virus infection. While advanced evidence is needed regarding its clinical features and mechanisms. We aimed to describe two phenotypes of AKI as well as their risk factors and the association with mortality.

METHODS

Consecutive hospitalized patients with COVID-19 in tertiary hospitals in Wuhan, China from 1 January 2020 to 23 March 2020 were included. Patients with AKI were classified as AKI-early and AKI-late according to the sequence of organ dysfunction (kidney as the first dysfunctional organ or not). Demographic and clinical features were compared between two AKI groups. Their risk factors and the associations with in-hospital mortality were analyzed.

RESULTS

A total of 4020 cases with laboratory-confirmed COVID-19 were included and 285 (7.09%) of them were identified as AKI. Compared with patients with AKI-early, patients with AKI-late had significantly higher levels of systemic inflammatory markers. Both AKIs were associated with an increased risk of in-hospital mortality, with similar fully adjusted hazard ratios of 2.46 [95% confidence interval (CI) 1.35-4.49] for AKI-early and 3.09 (95% CI 2.17-4.40) for AKI-late. Only hypertension was independently associated with the risk of AKI-early. While age, history of chronic kidney disease and the levels of inflammatory biomarkers were associated with the risk of AKI-late.

CONCLUSIONS

AKI among patients with COVID-19 has two clinical phenotypes, which could be due to different mechanisms. Considering the increased risk for mortality for both phenotypes, monitoring for AKI should be emphasized during COVID-19.

A narrative review on the basic and clinical aspects of the novel SARS-CoV-2, the etiologic agent of COVID-19

The novel SARS-CoV-2 is responsible for causing the ongoing outbreak of coronavirus disease 19 (COVID-19), a systemic infection in humans. Ever since it was first detected in December 2019, the number of confirmed cases has continued to increase. Within a short period, this disease has become a global issue, and therefore it is characterized as a pandemic. The current understanding and explanations are based on epidemiological, clinical and physiological observations. Besides, it remains a great challenge, as much remains to be understood about this new disease-causing virus. Therefore, we seek to provide an overview of SARS-CoV-2, including its classification, origin, genomic structure, replication cycle, transmission, pathogenesis, clinical aspects, diagnosis, treatments, prevention and vaccine options. We conducted a literature search for the articles published up to August 2020 using the keywords ‘SAR-CoV-2’ and ‘COVID19’ in medical databases; PubMed, google scholar, EMBASE, and web of science. Based on the information collected, the emerging COVID-19, caused by SARS-CoV-2, exhibits strong infectivity but less virulence in terms of severity of disease and mortality rates in certain age groups. It inflicts more damage in terms of peoples’ health and well-being, social life, and global economic impacts. Unfortunately, there is no adequate global and standard response to this pandemic to date, and each country is facing a crisis based on its situation, expertise, and hypotheses. While there is no effective therapy and vaccine against the novel SARS-CoV-2 yet, preventive measures are the only tool available to our disposal to control the spread of the COVID-19 pandemic. Ongoing and future research is focused more on developing standard treatment strategies, and efficacious vaccines, which would be useful to tackle this pandemic globally.

Cytokines and their relationship with the severity and prognosis of coronavirus disease 2019 (COVID-19): a retrospective cohort study

OBJECTIVE

To delineate the characteristics and clinical significance of plasma inflammatory cytokines altered in COVID-19.

DESIGN

Retrospective, single-centre cohort study.

SETTING

Tongji Hospital in Wuhan, China.

PARTICIPANTS

Among a cohort of 308 patients with a diagnosis of COVID-19, 138 patients died while 170 patients recovered and were discharged from the hospital. The data were collected until 27 February 2020.

PRIMARY AND SECONDARY OUTCOME MEASURES

Clinical characteristics and laboratory findings were obtained from electronic medical records using data collection forms.

RESULTS

The percentage of patients with elevated interleukin 2 receptor (IL-2R), IL-6, IL-8, IL-10 and tumour necrosis factor (TNF) increased with severity of disease (p<0.0001 for all). IL-2R (p<0.0001), IL-6 (p<0.0001), IL-8 (p=0.0001), IL-10 (p<0.0001) and TNF (p<0.0001) were also twofold to 20-fold higher in patients who died compared with those who recovered. Also, IL-6 and IL-10 increased in both the progressive patient groups: moderate (p=0.0026) and severe (p<0.0001). In multivariate analysis, higher levels of IL-2R (OR 1.001, 95% CI 1.000 to 1.002, p=0.031) and IL-6 (OR 1.013, 95% CI 1.003 to 1.024, p=0.015) on admission were associated with increasing odds of in-hospital death, independent of other covariates, including severity of disease and lymphocyte count.

CONCLUSION

Increased proinflammatory and anti-inflammatory cytokines, including IL-2R, IL-6, IL-8, TNF and IL-10, showed an obvious association with both COVID-19 severity and in-hospital mortality. Thus, our study indicates that cytokines are valuable in predicting the severity of COVID-19 and helps in distinguishing critically ill patients from the less affected ones.

Adjuvants for Coronavirus Vaccines

Vaccine development utilizing various platforms is one of the strategies that has been proposed to address the coronavirus disease 2019 (COVID-19) pandemic. Adjuvants are critical components of both subunit and certain inactivated vaccines because they induce specific immune responses that are more robust and long-lasting. A review of the history of coronavirus vaccine development demonstrates that only a few adjuvants, including aluminum salts, emulsions, and TLR agonists, have been formulated for the severe acute respiratory syndrome-associated coronavirus (SARS-CoV), Middle East respiratory syndrome-related coronavirus (MERS-CoV), and currently the SARS-CoV-2 vaccines in experimental and pre-clinical studies. However, there is still a lack of evidence regarding the effects of the adjuvants tested in coronavirus vaccines. This paper presents an overview of adjuvants that have been formulated in reported coronavirus vaccine studies, which should assist with the design and selection of adjuvants with optimal efficacy and safety profiles for COVID-19 vaccines.

Potential role of interferons in treating COVID-19 patients

The recently public health crises in the world is emerged by spreading the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) also named COVID-19. The virus is originated in bats and transported to humans via undefined intermediate animals. This virus can produce from weak to severe respiratory diseases including acute respiratory distress syndrome (ARDS), multiple organ dysfunction syndrome (MODS), pneumonia and even death in patients. The COVID-19 disease is distributed by inhalation via contaminated droplets or contact with infected environment. The incubation time is from 2 to 14 day and the symptoms are typically fever, sore throat, cough, malaise, fatigue, breathlessness among others. It needs to be considered that many infected people are asymptomatic. Developing various immunological and virological methods to diagnose this disease is supported by several laboratories. Treatment is principally supportive; however, there are several agents that are using in treating of COVID-19 patients. Interferons (IFNs) have shown to be crucial in fighting with COVID-19 disease and can be a suitable candidate in treatment of these patients. Combination therapy can be more effective than monotherapy to cure this disease. Prevention necessitates to be performed by isolation of suspected people and home quarantine as well as taking care to infected people with mild or strict disease at hospitals. As the outbreak of SARS-CoV-2 has accelerated, developing effective therapy is an urgent requirement to battle the virus and prevent further pandemic. In this manuscript we reviewed available information about SARS-CoV-2 and probable therapies for COVID-19 patients.

Severe Acute Respiratory Syndrome Coronavirus 2, COVID-19, and the Renin-Angiotensin System: Pressing Needs and Best Research Practices

The coronavirus disease 2019 (COVID-19) pandemic is associated with significant morbidity and mortality throughout the world, predominantly due to lung and cardiovascular injury. The virus responsible for COVID-19-severe acute respiratory syndrome coronavirus 2-gains entry into host cells via ACE2 (angiotensin-converting enzyme 2). ACE2 is a primary enzyme within the key counter-regulatory pathway of the renin-angiotensin system (RAS), which acts to oppose the actions of Ang (angiotensin) II by generating Ang-(1-7) to reduce inflammation and fibrosis and mitigate end organ damage. As COVID-19 spans multiple organ systems linked to the cardiovascular system, it is imperative to understand clearly how severe acute respiratory syndrome coronavirus 2 may affect the multifaceted RAS. In addition, recognition of the role of ACE2 and the RAS in COVID-19 has renewed interest in its role in the pathophysiology of cardiovascular disease in general. We provide researchers with a framework of best practices in basic and clinical research to interrogate the RAS using appropriate methodology, especially those who are relatively new to the field. This is crucial, as there are many limitations inherent in investigating the RAS in experimental models and in humans. We discuss sound methodological approaches to quantifying enzyme content and activity (ACE, ACE2), peptides (Ang II, Ang-[1-7]), and receptors (types 1 and 2 Ang II receptors, Mas receptor). Our goal is to ensure appropriate research methodology for investigations of the RAS in patients with severe acute respiratory syndrome coronavirus 2 and COVID-19 to ensure optimal rigor and reproducibility and appropriate interpretation of results from these investigations.

Role of Renin-Angiotensin System in Acute Lung Injury Caused by Viral Infection

The renin-angiotensin system (RAS) is the most important regulatory system of electrolyte homeostasis and blood pressure and acts through angiotensin-converting enzyme (ACE)/angiotensin II (Ang II)/Ang II type 1 (AT1) receptor axis and angiotensin-converting enzyme 2 (ACE2)/angiotensin (1-7)/MAS receptor axis. RAS dysfunction is related to the occurrence and development of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) and causes a serious prognosis and even death. ALI/ARDS can be induced by various ways, one of which is viral infections, such as SARS-CoV, SARS-CoV-2, H5N1, H7N9, and EV71. This article reviews the specific mechanism on how RAS dysfunction affects ALI/ARDs caused by viral infections. SARS-CoV and SARS-CoV-2 enter the host cells by binding with ACE2. H5N1 and H7N9 avian influenza viruses reduce the ACE2 level in the body, and EV71 increases Ang II concentration. Treatment with angiotensin-converting enzyme inhibitor and angiotensin AT1 receptor blocker can alleviate ALI/ARDS symptoms. This review provides suggestions for the treatment of lung injury caused by viral infections.

Cytokine Response in SARS-CoV-2 Infection in the Elderly

The last few months of 2019 witnessed the emergence, rise and rapid spread of a novel coronavirus known as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), causing an acute respiratory disease called coronavirus disease 2019 or Covid-19. Severe pathological manifestations of the disease in the infected population with comorbidities are linked to acute respiratory distress syndrome (ARDS), associated with an exaggerated synthesis and expression of cytokines, leading to a systemic inflammatory response also known as a cytokine storm (CS). Elderly patients (>60 years of age) showed more deaths in Covid-19 infection. Age-related immune imbalance increases patient susceptibility to CS. In acute Covid-19 infection, it is difficult to minimize or control the overproduction of cytokines; hence, limited medical treatments are effective. This review aims to provide an overview of the current knowledge of involvement of cytokines in SARS-CoV-2 infection, susceptibility factors for the accompanying cytokine storm in severe Covid-19 cases and possible treatment strategies.

Clinical characteristics of 132 healthcare worker cases with COVID-19: A retrospective study from a single center in Wuhan, China

Many healthcare workers (HCWs) have been confirmed to be infected with SARS-CoV-2 in China. A retrospective, single-center study was conducted. The median age of the 132 HCWs with COVID-19 was 32 years, with 92 (69.7%) being females. There were 47 (35.6%) doctors, 72 (54.6%) nurses, and 13 (9.9%) other HCWs. Ten of the 132 patients (7.6%) had underlying diseases. The most common symptoms of illness onset were fever (70, 53.0%), cough (66, 50.0%), and fatigue (58, 43.9%). All patients were categorized into mild or moderate COVID-19 type on admission to hospital, and five (3.8%) progressed to the severe COVID-19 type. Sixty-six HCWs patients were included in both the early and later discharged group. In the logistic analysis, the later discharged patients had a longer time for illness onset to hospital admission (per 1 day; OR, 1.10; 95% CI, 1.03-1.18; p = .006), a higher proportion of >3 onset symptoms clustering (OR, 3.11; 95% CI, 1.27-7.62; p = .01), and a higher percentage of other HCWs (OR, 6.20; 95% CI, 1.49-25.80; p = .01). HCW patients were young female nurses with fewer comorbidities, and most were mild or moderate COVID-19 type. The later discharged patients exhibited characteristics of longer time for illness onset to hospitalization and clustering of onset symptoms.

A pharmacological perspective of chloroquine in SARS-CoV-2 infection: An old drug for the fight against a new coronavirus?

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is having serious consequences on health and the economy worldwide. All evidence-based treatment strategies need to be considered to combat this new virus. Drugs need to be considered on scientific grounds of efficacy, safety and cost. Chloroquine (CQ) and hydroxychloroquine (HCQ) are old drugs used in the treatment of malaria. Moreover, their antiviral properties have been previously studied, including against coronaviruses, where evidence of efficacy has been found. In the current race against time triggered by the COVID-19 pandemic, the search for new antivirals is very important. However, consideration should be given to old drugs with known anti-coronavirus activity, such as CQ and HCQ. These could be integrated into current treatment strategies while novel treatments are awaited, also in light of the fact that they display an anticoagulant effect that facilitates the activity of low-molecular-weight heparin, aimed at preventing acute respiratory distress syndrome (ARDS)-associated thrombotic events. The safety of CQ and HCQ has been studied for over 50 years, however recently published data raise concerns for cardiac toxicity of CQ/HCQ in patients with COVID-19. This review also re-examines the real information provided by some of the published alarming reports, although concluding that cardiac toxicity should in any case be stringently monitored in patients receiving CQ/HCQ.

Pregnancy and COVID-19: management and challenges

The consequences of COVID-19 infecting pregnant women and the potential risks of vertical transmission have become a major issue. Since little is currently known about COVID-19 in pregnancy, the understanding of COVID-19 in this particular group will be updated in time, and a comprehensive review will be useful to evaluate the impact of COVID-19 in pregnancy. Based on recently published literature and official documents, this review provides an introduction to the pathogenesis, pathology, and clinical features of COVID-19 and has focused on the current researches on clinical features, pregnancy outcomes and placental histopathological analysis from pregnant women infected with SARS-CoV-2 in comparison with SARS-CoV and MERS-CoV. These viruses trigger a cytokine storm in the body, produce a series of immune responses, and cause changes in peripheral leukocytes and immune system cells leading to pregnancy complications that may be associated with viral infections. The expression of ACE2 receptors in the vascular endothelium may explain the histological changes of placentas from pregnant women infected by SARS-CoV-2. Pregnant women with COVID-19 pneumonia show similar clinical characteristics compared with non-pregnant counterparts. Although there is no unequivocal evidence to support the fetal infection by intrauterine vertical transmission of SARS, MERS and SARS-CoV-2 so far, more and more articles began to report maternal deaths due to COVID-19. In particular, from February 26, 2020 (date of the first COVID-19 case reported in Brazil) until June 18, 2020, Brazil reported 124 maternal deaths. Therefore, pregnant women and neonates require special attention regarding the prevention, diagnosis and management of COVID-19.

The Comparative Immunological Characteristics of SARS-CoV, MERS-CoV, and SARS-CoV-2 Coronavirus Infections

Immune dysfunction and aberrant cytokine storms often lead to rapid exacerbation of the disease during late infection stages in SARS-CoV and MERS-CoV patients. However, the underlying immunopathology mechanisms are not fully understood, and there has been little progress in research regarding the development of vaccines, anti-viral drugs, and immunotherapy. The newly discovered SARS-CoV-2 (2019-nCoV) is responsible for the third coronavirus pandemic in the human population, and this virus exhibits enhanced pathogenicity and transmissibility. SARS-CoV-2 is highly genetically homologous to SARS-CoV, and infection may result in a similar clinical disease (COVID-19). In this review, we provide detailed knowledge of the pathogenesis and immunological characteristics of SARS and MERS, and we present recent findings regarding the clinical features and potential immunopathogenesis of COVID-19. Host immunological characteristics of these three infections are summarised and compared. We aim to provide insights and scientific evidence regarding the pathogenesis of COVID-19 and therapeutic strategies targeting this disease.

Overview of Immune Response During SARS-CoV-2 Infection: Lessons From the Past

After the 1918 flu pandemic, the world is again facing a similar situation. However, the advancement in medical science has made it possible to identify that the novel infectious agent is from the coronavirus family. Rapid genome sequencing by various groups helped in identifying the structure and function of the virus, its immunogenicity in diverse populations, and potential preventive measures. Coronavirus attacks the respiratory system, causing pneumonia and lymphopenia in infected individuals. Viral components like spike and nucleocapsid proteins trigger an immune response in the host to eliminate the virus. These viral antigens can be either recognized by the B cells or presented by MHC complexes to the T cells, resulting in antibody production, increased cytokine secretion, and cytolytic activity in the acute phase of infection. Genetic polymorphism in MHC enables it to present some of the T cell epitopes very well over the other MHC alleles. The association of MHC alleles and its downregulated expression has been correlated with disease severity against influenza and coronaviruses. Studies have reported that infected individuals can, after recovery, induce strong protective responses by generating a memory T-cell pool against SARS-CoV and MERS-CoV. These memory T cells were not persistent in the long term and, upon reactivation, caused local damage due to cross-reactivity. So far, the reports suggest that SARS-CoV-2, which is highly contagious, shows related symptoms in three different stages and develops an exhaustive T-cell pool at higher loads of viral infection. As there are no specific treatments available for this novel coronavirus, numerous small molecular drugs that are being used for the treatment of diseases like SARS, MERS, HIV, ebola, malaria, and tuberculosis are being given to COVID-19 patients, and clinical trials for many such drugs have already begun. A classical immunotherapy of convalescent plasma transfusion from recovered patients has also been initiated for the neutralization of viremia in terminally ill COVID-19 patients. Due to the limitations of plasma transfusion, researchers are now focusing on developing neutralizing antibodies against virus particles along with immuno-modulation of cytokines like IL-6, Type I interferons (IFNs), and TNF-α that could help in combating the infection. This review highlights the similarities of the coronaviruses that caused SARS and MERS to the novel SARS-CoV-2 in relation to their pathogenicity and immunogenicity and also focuses on various treatment strategies that could be employed for curing COVID-19.

Low-contact and high-interconnectivity pathology (LC&HI Path): post-COVID19-pandemic practice of pathology

The COVID-19 pandemic situation may be viewed as an opportunity to accelerate some of the ongoing transformations in modern pathology. This refers primarily to the digitalisation of the practice of tissue and cellular pathology diagnostics. However, it is also an opportunity to analyse the modus operandi of a discipline that has been practised in a similar manner for more than 100 years. The challenge is to define the next generation of interconnectivity tools that would be necessary to achieve a new operational model that, while ensuring low face-to-face interaction between the main players of the diagnostic pipeline, allows maximum interconnectivity to serve our patients and the immediate teaching and research needs associated with clinical tissue/cellular samples. This viewpoint aims to describe what this new paradigm, a low-contact and high-interconnectivity pathology (LC&HC Path) operation, may require in the near future.

Potential for jaktinib hydrochloride to treat cytokine storms in patients with COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has become a serious public health threat to the whole world, and the number of infected is still rising dramatically at this moment. Several studies have confirmed that cytokine storms play a critical role in causing a case to worsen from mild to severe or critical. The current treatment for cytokine storms is limited, so the international medical community is focusing on a specific and effective remedy. Jaktinib hydrochloride is a broad spectrum JAK inhibitor. It can inhibit cytokine-induced immune activation by multiple mechanisms and also slow viral proliferation by inhibiting AAK1 without causing unacceptable toxicity. Jaktinib hydrochloride has great potential for the treatment of patients with coronavirus disease 2019 (COVID-19).

Coupled CRC 2D and ALI 3D Cultures Express Receptors of Emerging Viruses and Are More Suitable for the Study of Viral Infections Compared to Conventional Cell Lines

Infections of emerging and reemerging viruses (SARS-CoVs, influenza H1N1, etc.) largely and globally affect human health. Animal models often fail to reflect a physiological status because of species tropism of virus infection. Conventional cell lines are usually genetically and phenotypically different from primary cells. Developing an in vitro physiological model to study the infection of emerging viruses will facilitate our understanding of virus-host cell interactions, thereby benefiting antiviral drug discovery. In the current work, we first established normal airway epithelial cells (upper and lower airway track) in 2D and 3D culture systems using conditional reprogramming (CR) and air-liquid interface (ALI) techniques. These long-term cultures maintained differentiation potential. More importantly, these cells express two types of influenza virus receptors, α2-6-Gal- and α2-3-Gal-linked sialic acids, and angiotensin-converting enzyme 2 (ACE2), a receptor for SARS-CoVs as well. These cells were permissive to the infection of pandemic influenza H1N1 (H1N1pdm). In contrast, the lung cancer cell line A549 and immortalized airway epithelial cells (16HBE) were not susceptible to H1N1 infection. A virus-induced cytopathic effect (CPE) on 2D CRC cultures developed in a time-dependent manner. The pathological effects were also readily observed spreading from the apical layer to the basal layer of the 3D ALI culture. This integrated 2D CRC and 3D ALI cultures provide a physiological and personalized in vitro model to study the infection of emerging viruses. This novel model can be used for studying virus biology and host response to viral infection and for antiviral drug discovery.

Digital pathology and artificial intelligence will be key to supporting clinical and academic cellular pathology through COVID-19 and future crises: the PathLAKE consortium perspective

The measures to control the COVID-19 outbreak will likely remain a feature of our working lives until a suitable vaccine or treatment is found. The pandemic has had a substantial impact on clinical services, including cancer pathways. Pathologists are working remotely in many circumstances to protect themselves, colleagues, family members and the delivery of clinical services. The effects of COVID-19 on research and clinical trials have also been significant with changes to protocols, suspensions of studies and redeployment of resources to COVID-19. In this article, we explore the specific impact of COVID-19 on clinical and academic pathology and explore how digital pathology and artificial intelligence can play a key role to safeguarding clinical services and pathology-based research in the current climate and in the future.

Long Term Culture of Human Kidney Proximal Tubule Epithelial Cells Maintains Lineage Functions and Serves as an Ex vivo Model for Coronavirus Associated Kidney Injury

The mechanism of how SARS-CoV-2 causes severe multi-organ failure is largely unknown. Acute kidney injury (AKI) is one of the frequent organ damage in severe COVID-19 patients. Previous studies have shown that human renal tubule cells could be the potential host cells targeted by SARS-CoV-2. Traditional cancer cell lines or immortalized cell lines are genetically and phenotypically different from host cells. Animal models are widely used, but often fail to reflect a physiological and pathogenic status because of species tropisms. There is an unmet need for normal human epithelial cells for disease modeling. In this study, we successfully established long term cultures of normal human kidney proximal tubule epithelial cells (KPTECs) in 2D and 3D culture systems using conditional reprogramming (CR) and organoids techniques. These cells had the ability to differentiate and repair DNA damage, and showed no transforming property. Importantly, the CR KPTECs maintained lineage function with expression of specific transporters (SLC34A3 and cubilin). They also expressed angiotensin-converting enzyme 2 (ACE2), a receptor for SARS-CoV and SARS-CoV-2. In contrast, cancer cell line did not express endogenous SLC34A3, cubilin and ACE2. Very interestingly, ACE2 expression was around twofold higher in 3D organoids culture compared to that in 2D CR culture condition. Pseudovirion assays demonstrated that SARS-CoV spike (S) protein was able to enter CR cells with luciferase reporter. This integrated 2D CR and 3D organoid cultures provide a physiological ex vivo model to study kidney functions, innate immune response of kidney cells to viruses, and a novel platform for drug discovery and safety evaluation.

Flattening the COVID-19 Curve With Natural Killer Cell Based Immunotherapies

Natural Killer (NK) cells are innate immune responders critical for viral clearance and immunomodulation. Despite their vital role in viral infection, the contribution of NK cells in fighting SARS-CoV-2 has not yet been directly investigated. Insights into pathophysiology and therapeutic opportunities can therefore be inferred from studies assessing NK cell phenotype and function during SARS, MERS, and COVID-19. These studies suggest a reduction in circulating NK cell numbers and/or an exhausted phenotype following infection and hint toward the dampening of NK cell responses by coronaviruses. Reduced circulating NK cell levels and exhaustion may be directly responsible for the progression and severity of COVID-19. Conversely, in light of data linking inflammation with coronavirus disease severity, it is necessary to examine NK cell potential in mediating immunopathology. A common feature of coronavirus infections is that significant morbidity and mortality is associated with lung injury and acute respiratory distress syndrome resulting from an exaggerated immune response, of which NK cells are an important component. In this review, we summarize the current understanding of how NK cells respond in both early and late coronavirus infections, and the implication for ongoing COVID-19 clinical trials. Using this immunological lens, we outline recommendations for therapeutic strategies against COVID-19 in clearing the virus while preventing the harm of immunopathological responses.