Synergistic Detrimental Effects of Cigarette Smoke, Alcohol, and SARS-CoV-2 in COPD Bronchial Epithelial Cells.

Lung conditions such as COPD, as well as risk factors such as alcohol misuse and cigarette smoking, can exacerbate COVID-19 disease severity. Synergistically, these risk factors can have a significant impact on immunity against pathogens. Here, we studied the effect of a short exposure to alcohol and/or cigarette smoke extract (CSE) in vitro on acute SARS-CoV-2 infection of ciliated human bronchial epithelial cells (HBECs) collected from healthy and COPD donors. We observed an increase in viral titer in CSE- or alcohol-treated COPD HBECs compared to untreated COPD HBECs. Furthermore, we treated healthy HBECs accompanied by enhanced lactate dehydrogenase activity, indicating exacerbated injury. Finally, IL-8 secretion was elevated due to the synergistic damage mediated by alcohol, CSE, and SARS-CoV-2 in COPD HBECs. Together, our data suggest that, with pre-existing COPD, short exposure to alcohol or CSE is sufficient to exacerbate SARS-CoV-2 infection and associated injury, impairing lung defences.

Malondialdehyde acetaldehyde adduction of surfactant protein D attenuates SARS-CoV-2 spike protein binding and virus neutralization.

BACKGROUND: Over 43% of the world's population regularly consumes alcohol. Although not commonly known, alcohol can have a significant impact on the respiratory environment. Living in the time of the COVID-19 pandemic, alcohol misuse can have a particularly deleterious effect on SARS-CoV-2-infected individuals and, in turn, the overall healthcare system. Patients with alcohol use disorders have higher odds of COVID-19-associated hospitalization and mortality. Even though the detrimental role of alcohol on COVID-19 outcomes has been established, the underlying mechanisms are yet to be fully understood. Alcohol misuse has been shown to induce oxidative damage in the lungs through the production of reactive aldehydes such as malondialdehyde and acetaldehyde (MAA). MAA can then form adducts with proteins, altering their structure and function. One such protein is surfactant protein D (SPD), which plays an important role in innate immunity against pathogens. METHODS AND RESULTS: In this study, we examined whether MAA adduction of SPD (SPD-MAA) attenuates the ability of SPD to bind SARS-CoV-2 spike protein, reversing SPD-mediated virus neutralization. Using ELISA, we show that SPD-MAA is unable to competitively bind spike protein and prevent ACE2 receptor binding. Similarly, SPD-MAA fails to inhibit entry of wild-type SARS-CoV-2 virus into Calu-3 cells, a lung epithelial cell line, as well as ciliated primary human bronchial epithelial cells isolated from healthy individuals. CONCLUSIONS: Overall, MAA adduction of SPD, a consequence of alcohol overconsumption, represents one mechanism of compromised lung innate defense against SARS-CoV-2, highlighting a possible mechanism underlying COVID-19 severity and related mortality in patients who misuse alcohol.

Nanofiber capsules for minimally invasive sampling of biological specimens from gastrointestinal tract.

Accurate and rapid point-of-care tissue and microbiome sampling is critical for early detection of cancers and infectious diseases and often result in effective early intervention and prevention of disease spread. In particular, the low prevalence of Barrett's and gastric premalignancy in the Western world makes population-based endoscopic screening unfeasible and cost-ineffective. Herein, we report a method that may be useful for prescreening the general population in a minimally invasive way using a swallowable, re-expandable, ultra-absorbable, and retrievable nanofiber cuboid and sphere produced by electrospinning, gas-foaming, coating, and crosslinking. The water absorption capacity of the cuboid- and sphere-shaped nanofiber objects is shown ∼6000% and ∼2000% of their dry mass. In contrast, unexpanded semicircular and square nanofiber membranes showed <500% of their dry mass. Moreover, the swallowable sphere and cuboid were able to collect and release more bacteria, viruses, and cells/tissues from solutions as compared with unexpanded scaffolds. In addition to that, an expanded sphere shows higher cell collection capacity from the esophagus inner wall as compared with the unexpanded nanofiber membrane. Taken together, the nanofiber capsules developed in this study could provide a minimally invasive method of collecting biological samples from the duodenal, gastric, esophagus, and oropharyngeal sites, potentially leading to timely and accurate diagnosis of many diseases. STATEMENT OF SIGNIFICANCE: Recently, minimally invasive technologies have gained much attention in tissue engineering and disease diagnosis. In this study, we engineered a swallowable and retrievable electrospun nanofiber capsule serving as collection device to collect specimens from internal organs in a minimally invasive manner. The sample collection device could be an alternative endoscopy to collect the samples from internal organs like jejunum, stomach, esophagus, and oropharynx without any sedation. The newly engineered nanofiber capsule could be used to collect, bacteria, virus, fluids, and cells from the abovementioned internal organs. In addition, the biocompatible and biodegradable nanofiber capsule on a string could exhibit a great sample collection capacity for the primary screening of Barret Esophagus, acid reflux, SARS-COVID-19, Helicobacter pylori, and gastric cancer.

Improved Database Filtering Technology Enables More Efficient Ab Initio Design of Potent Peptides against Ebola Viruses.

The rapid mutations of viruses such as SARS-CoV-2 require vaccine updates and the development of novel antiviral drugs. This article presents an improved database filtering technology for a more effective design of novel antiviral agents. Different from the previous approach, where the most probable parameters were obtained stepwise from the antimicrobial peptide database, we found it possible to accelerate the design process by deriving multiple parameters in a single step during the peptide amino acid analysis. The resulting peptide DFTavP1 displays the ability to inhibit Ebola virus. A deviation from the most probable peptide parameters reduces antiviral activity. The designed peptides appear to block viral entry. In addition, the amino acid signature provides a clue to peptide engineering to gain cell selectivity. Like human cathelicidin LL-37, our engineered peptide DDIP1 inhibits both Ebola and SARS-CoV-2 viruses. These peptides, with broad antiviral activity, may selectively disrupt viral envelopes and offer the lasting efficacy required to treat various RNA viruses, including their emerging mutants.

SARS-CoV-2 Dysregulates Neutrophil Degranulation and Reduces Lymphocyte Counts.

SARS-CoV-2, the virus that causes COVID-19, has given rise to one of the largest pandemics, affecting millions worldwide. High neutrophil-to-lymphocyte ratios have been identified as an important correlate to poor recovery rates in severe COVID-19 patients. However, the mechanisms underlying this clinical outcome and the reasons for its correlation to poor prognosis are unclear. Furthermore, the mechanisms involved in healthy neutrophils acquiring a SARS-CoV-2-mediated detrimental role are yet to be fully understood. In this study, we isolated circulating neutrophils from healthy donors for treatment with supernates from infected epithelial cells and direct infection with SARS-CoV-2 in vitro. Infected epithelial cells induced a dysregulated degranulation of primary granules with a decrease in myeloperoxidase (MPO), but slight increase in neutrophil elastase release. Infection of neutrophils resulted in an impairment of both MPO and elastase release, even though CD16 receptor shedding was upregulated. Importantly, SARS-CoV-2-infected neutrophils had a direct effect on peripheral blood lymphocyte counts, with decreasing numbers of CD19+ B cells, CD8+ T cells, and CD4+ T cells. Together, this study highlights the independent role of neutrophils in contributing to the aberrant immune responses observed during SARS-CoV-2 infection that may be further dysregulated in the presence of other immune cells.

Author Correction: Aerosol and surface contamination of SARS-CoV-2 observed in quarantine and isolation care.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

The size and culturability of patient-generated SARS-CoV-2 aerosol.

BACKGROUND: Aerosol transmission of COVID-19 is the subject of ongoing policy debate. Characterizing aerosol produced by people with COVID-19 is critical to understanding the role of aerosols in transmission. OBJECTIVE: We investigated the presence of virus in size-fractioned aerosols from six COVID-19 patients admitted into mixed acuity wards in April of 2020. METHODS: Size-fractionated aerosol samples and aerosol size distributions were collected from COVID-19 positive patients. Aerosol samples were analyzed for viral RNA, positive samples were cultured in Vero E6 cells. Serial RT-PCR of cells indicated samples where viral replication was likely occurring. Viral presence was also investigated by western blot and transmission electron microscopy (TEM). RESULTS: SARS-CoV-2 RNA was detected by rRT-PCR in all samples. Three samples confidently indicated the presence of viral replication, all of which were from collected sub-micron aerosol. Western blot indicated the presence of viral proteins in all but one of these samples, and intact virions were observed by TEM in one sample. SIGNIFICANCE: Observations of viral replication in the culture of submicron aerosol samples provides additional evidence that airborne transmission of COVID-19 is possible. These results support the use of efficient respiratory protection in both healthcare and by the public to limit transmission.

Bromodomain and Extraterminal Protein Inhibitor, Apabetalone (RVX-208), Reduces ACE2 Expression and Attenuates SARS-Cov-2 Infection In Vitro.

Effective therapeutics are urgently needed to counter infection and improve outcomes for patients suffering from COVID-19 and to combat this pandemic. Manipulation of epigenetic machinery to influence viral infectivity of host cells is a relatively unexplored area. The bromodomain and extraterminal (BET) family of epigenetic readers have been reported to modulate SARS-CoV-2 infection. Herein, we demonstrate apabetalone, the most clinical advanced BET inhibitor, downregulates expression of cell surface receptors involved in SARS-CoV-2 entry, including angiotensin-converting enzyme 2 (ACE2) and dipeptidyl-peptidase 4 (DPP4 or CD26) in SARS-CoV-2 permissive cells. Moreover, we show that apabetalone inhibits SARS-CoV-2 infection in vitro to levels comparable to those of antiviral agents. Taken together, our study supports further evaluation of apabetalone to treat COVID-19, either alone or in combination with emerging therapeutics.

Repurposing Quinoline and Artemisinin Antimalarials as Therapeutics for SARS-CoV-2: Rationale and Implications.

The coronavirus disease-2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected more than 116 million individuals globally and resulted in over 2.5 million deaths since the first report in December 2019. For most of this time, healthcare professionals have had few tools at their disposal. In December 2020, several vaccines that were shown to be highly effective have been granted emergency use authorization (EUA). Despite these remarkable breakthroughs, challenges include vaccine roll-out and implementation, in addition to deeply entrenched antivaccination viewpoints. While vaccines will prevent disease occurrence, infected individuals still need treatment options, and repurposing drugs circumvents the lengthy and costly process of drug development. SARS-CoV-2, like many other enveloped viruses, require the action of host proteases for entry. In addition, this novel virus employs a unique method of cell exit of deacidified lysosomes and exocytosis. Thus, inhibitors of lysosomes or other players in this pathway are good candidates to target SARS-CoV-2. Chemical compounds in the quinoline class are known to be lysomotropic and perturb pH levels. A large number of quinolines are FDA-approved for treatment of inflammatory diseases and antimalarials. Artemisinins are another class of drugs that have been demonstrated to be safe for use in humans and are widely utilized as antimalarials. In this Review, we discuss the use of antimalarial drugs in the class of quinolines and artemisinins, which have been shown to be effective against SARS-CoV-2 in vitro and in vivo, and provide a rationale in employing quinolines as treatment of SARS-CoV-2 in clinical settings.

Diagnostics for SARS-CoV-2 infections.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread to nearly every corner of the globe, causing societal instability. The resultant coronavirus disease 2019 (COVID-19) leads to fever, sore throat, cough, chest and muscle pain, dyspnoea, confusion, anosmia, ageusia and headache. These can progress to life-threatening respiratory insufficiency, also affecting the heart, kidney, liver and nervous systems. The diagnosis of SARS-CoV-2 infection is often confused with that of influenza and seasonal upper respiratory tract viral infections. Due to available treatment strategies and required containments, rapid diagnosis is mandated. This Review brings clarity to the rapidly growing body of available and in-development diagnostic tests, including nanomaterial-based tools. It serves as a resource guide for scientists, physicians, students and the public at large.

Ultra-absorptive Nanofiber Swabs for Improved Collection and Test Sensitivity of SARS-CoV-2 and other Biological Specimens.

Following the COVID-19 outbreak, swabs for biological specimen collection were thrust to the forefront of healthcare materials. Swab sample collection and recovery are vital for reducing false negative diagnostic tests, early detection of pathogens, and harvesting DNA from limited biological samples. In this study, we report a new class of nanofiber swabs tipped with hierarchical 3D nanofiber objects produced by expanding electrospun membranes with a solids-of-revolution-inspired gas foaming technique. Nanofiber swabs significantly improve absorption and release of proteins, cells, bacteria, DNA, and viruses from solutions and surfaces. Implementation of nanofiber swabs in SARS-CoV-2 detection reduces the false negative rates at two viral concentrations and identifies SARS-CoV-2 at a 10× lower viral concentration compared to flocked and cotton swabs. The nanofiber swabs show great promise in improving test sensitivity, potentially leading to timely and accurate diagnosis of many diseases.

Pharmacotherapeutics of SARS-CoV-2 Infections.

The COVID-19 pandemic has affected more than 38 million people world-wide by person to person transmission of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Therapeutic and preventative strategies for SARS-CoV-2 remains a significant challenge. Within the past several months, effective treatment options have emerged and now include repurposed antivirals, corticosteroids and virus-specific antibodies. The latter has included convalescence plasma and monoclonal antibodies. Complete viral eradication will be achieved through an effective, safe and preventative vaccine. To now provide a comprehensive summary for each of the pharmacotherapeutics and preventative strategies being offered or soon to be developed for SARS-CoV-2.

Animal models for SARS-CoV-2 research: A comprehensive literature review.

Emerging and re-emerging viral diseases can create devastating effects on human lives and may also lead to economic crises. The ongoing COVID-19 pandemic due to the novel coronavirus (nCoV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which originated in Wuhan, China, has caused a global public health emergency. To date, the molecular mechanism of transmission of SARS-CoV-2, its clinical manifestations and pathogenesis is not completely understood. The global scientific community has intensified its efforts in understanding the biology of SARS-CoV-2 for development of vaccines and therapeutic interventions to prevent the rapid spread of the virus and to control mortality and morbidity associated with COVID-19. To understand the pathophysiology of SARS-CoV-2, appropriate animal models that mimic the biology of human SARS-CoV-2 infection are urgently needed. In this review, we outline animal models that have been used to study previous human coronaviruses (HCoVs), including severe acute respiratory syndrome coronavirus (SARS-CoV) and middle east respiratory syndrome coronavirus (MERS-CoV). Importantly, we discuss models that are appropriate for SARS-CoV-2 as well as the advantages and disadvantages of various available methods.

Bromelain Inhibits SARS-CoV-2 Infection in VeroE6 Cells.

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The initial interaction between Transmembrane Serine Protease 2 (TMPRSS2) primed SARS-CoV-2 spike (S) protein and host cell receptor angiotensin-converting enzyme 2 (ACE-2) is a pre-requisite step for this novel coronavirus pathogenesis. Here, we expressed a GFP-tagged SARS-CoV-2 S-Ectodomain in Tni insect cells. That contained sialic acid-enriched N- and O-glycans. Surface resonance plasmon (SPR) and Luminex assay showed that the purified S-Ectodomain binding to human ACE-2 and immunoreactivity with COVID-19 positive samples. We demonstrate that bromelain (isolated from pineapple stem and used as a dietary supplement) treatment diminishes the expression of ACE-2 and TMPRSS2 in VeroE6 cells and dramatically lowers the expression of S-Ectodomain. Importantly, bromelain treatment reduced the interaction between S-Ectodomain and VeroE6 cells. Most importantly, bromelain treatment significantly diminished the SARS-CoV-2 infection in VeroE6 cells. Altogether, our results suggest that bromelain or bromelain rich pineapple stem may be used as an antiviral against COVID-19. HIGHLIGHTS: Bromelain inhibits / cleaves the expression of ACE-2 and TMPRSS2Bromelain cleaves / degrades SARS-CoV-2 spike proteinBromelain inhibits S-Ectodomain binding and SARS-CoV-2 infection.

Immuno-epidemiology and pathophysiology of coronavirus disease 2019 (COVID-19).

Occasional zoonotic viral attacks on immunologically naive populations result in massive death tolls that are capable of threatening human survival. Currently, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the infectious agent that causes coronavirus disease (COVID-19), has spread from its epicenter in Wuhan China to all parts of the globe. Real-time mapping of new infections across the globe has revealed that variable transmission patterns and pathogenicity are associated with differences in SARS-CoV-2 lineages, clades, and strains. Thus, we reviewed how changes in the SARS-CoV-2 genome and its structural architecture affect viral replication, immune evasion, and transmission within different human populations. We also looked at which immune dominant regions of SARS-CoV-2 and other coronaviruses are recognized by Major Histocompatibility Complex (MHC)/Human Leukocyte Antigens (HLA) genes and how this could impact on subsequent disease pathogenesis. Efforts were also placed on understanding immunological changes that occur when exposed individuals either remain asymptomatic or fail to control the virus and later develop systemic complications. Published autopsy studies that reveal alterations in the lung immune microenvironment, morphological, and pathological changes are also explored within the context of the review. Understanding the true correlates of protection and determining how constant virus evolution impacts on host-pathogen interactions could help identify which populations are at high risk and later inform future vaccine and therapeutic interventions.

Aerosol and surface contamination of SARS-CoV-2 observed in quarantine and isolation care.

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) originated in Wuhan, China in late 2019, and its resulting coronavirus disease, COVID-19, was declared a pandemic by the World Health Organization on March 11, 2020. The rapid global spread of COVID-19 represents perhaps the most significant public health emergency in a century. As the pandemic progressed, a continued paucity of evidence on routes of SARS-CoV-2 transmission has resulted in shifting infection prevention and control guidelines between classically-defined airborne and droplet precautions. During the initial isolation of 13 individuals with COVID-19 at the University of Nebraska Medical Center, we collected air and surface samples to examine viral shedding from isolated individuals. We detected viral contamination among all samples, supporting the use of airborne isolation precautions when caring for COVID-19 patients.

Molecular Aspects of COVID-19 Differential Pathogenesis.

In the absence of therapeutic interventions, and a possible vaccine candidate, the spread of COVID-19 disease and associated fatalities are on the rise. The high mutation frequency in the genomic material of these viruses supports their ability to adapt to new environments, resulting in an efficient alteration in tissue tropism and host range. Therefore, the coronavirus' health threats could be relevant for the long-term. The epidemiological data indicate that age, sex, and cardio-metabolic disease have a significant impact on the spread and severity of COVID-19. In this review, we highlight recent updates on the pathogenesis of SARS-CoV-2 among men and women, including children. We also discuss the role of the cellular receptors and coreceptors used by the virus to enter host cells on differential infection among men, women, and cardio-metabolic patients.