Airway Hygiene in COVID-19 Pneumonia: Treatment Responses of 3 Critically Ill Cruise Ship Employees

Mechanical Ventilation-Related High Stretch Mainly Induces Endoplasmic Reticulum Stress and Thus Mediates Inflammation Response in Cultured Human Primary Airway Smooth Muscle Cells

Ventilator-induced lung injury (VILI) occurs in mechanically ventilated patients of respiratory disease and is typically characterized by airway inflammation. However, recent studies increasingly indicate that a major cause of VILI may be the excessive mechanical loading such as high stretch (>10% strain) on airway smooth muscle cells (ASMCs) due to mechanical ventilation (MV). Although ASMCs are the primary mechanosensitive cells in airways and contribute to various airway inflammation diseases, it is still unclear how they respond to high stretch and what mediates such a response. Therefore, we used whole genome-wide mRNA-sequencing (mRNA-Seq), bioinformatics, and functional identification to systematically analyze the mRNA expression profiles and signaling pathway enrichment of cultured human ASMCs exposed to high stretch (13% strain), aiming to screen the susceptible signaling pathway through which cells respond to high stretch. The data revealed that in response to high stretch, 111 mRNAs with count ≥100 in ASMCs were significantly differentially expressed (defined as DE-mRNAs). These DE-mRNAs are mainly enriched in endoplasmic reticulum (ER) stress-related signaling pathways. ER stress inhibitor (TUDCA) abolished high-stretch-enhanced mRNA expression of genes associated with ER stress, downstream inflammation signaling, and major inflammatory cytokines. These results demonstrate in a data-driven approach that in ASMCs, high stretch mainly induced ER stress and activated ER stress-related signaling and downstream inflammation response. Therefore, it suggests that ER stress and related signaling pathways in ASMCs may be potential targets for timely diagnosis and intervention of MV-related pulmonary airway diseases such as VILI.

Serratiopeptidase: An integrated View of Multifaceted Therapeutic Enzyme

Microbial products have been used for the treatment of different diseases for many centuries. The serratiopeptidase enzyme provides a new hope for COVID-19-infected patients. Nowadays, anti-inflammatory drugs are easy to obtain at minimal expenditure from microbial sources. Serratia sp. is identified as one of the most efficient bacteria produced from serratiopeptidase. Screening for new and efficient bacterial strains from different sources has been of interest in recent years. Serratiopeptidase remains the most well-known anti-inflammatory drug of choice. Serratiopeptidase is a cheaper and safer anti-inflammatory drug alternative to NSAIDs. The multifaceted properties of serratiopeptidase may lead towards arthritis, diabetes, cancer and thrombolytic treatments. Existing serratiopeptidase treatments in combination with antibiotics are popular in the treatment of postoperative swelling. Although an exclusive number of serratiopeptidase-producing strains have been derived, there is an urge for new recombinant strains to enhance the production of the enzyme. This review explores the properties of serratiopeptidase, different therapeutic aspects, industrial production, and various analytical techniques used in enzyme recovery. In addition, the review highlights the therapeutic and clinical aspects of the serratiopeptidase enzyme to combat COVID-19-induced respiratory syndrome.

Goblet Cell Hyperplasia Increases SARS-CoV-2 Infection in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is one of the underlying conditions in adults of any age that place them at risk for developing severe illnesses associated with COVID-19. To determine whether SARS-CoV-2's cellular tropism plays a critical role in severe pathophysiology in the lung, we investigated its host cell entry receptor distribution in the bronchial airway epithelium of healthy adults and high-risk adults (those with COPD). We found that SARS-CoV-2 preferentially infects goblet cells in the bronchial airway epithelium, as mostly goblet cells harbor the entry receptor angiotensin-converting enzyme 2 (ACE2) and its cofactor transmembrane serine protease 2 (TMPRSS2). We also found that SARS-CoV-2 replication was substantially increased in the COPD bronchial airway epithelium, likely due to COPD-associated goblet cell hyperplasia. Likewise, SARS-CoV and Middle East respiratory syndrome (MERS-CoV) infection increased disease pathophysiology (e.g., syncytium formation) in the COPD bronchial airway epithelium. Our results reveal that goblet cells play a critical role in SARS-CoV-2-induced pathophysiology in the lung. IMPORTANCE SARS-CoV-2 or COVID-19's first case was discovered in December 2019 in Wuhan, China, and by March 2020 it was declared a pandemic by the WHO. It has been shown that various underlying conditions can increase the chance of having severe COVID-19. COPD, which is the third leading cause of death worldwide, is one of the conditions listed by the CDC which can increase the chance of severe COVID-19. The present study uses a healthy and COPD-derived bronchial airway epithelial model to study the COVID-19 and host factors which could explain the reason for COPD patients developing severe infection due to COVID-19.

Stable nebulization and muco-trapping properties of regdanvimab/IN-006 support its development as a potent, dose-saving inhaled therapy for COVID-19

The respiratory tract represents the key target for antiviral delivery in early interventions to prevent severe COVID-19. While neutralizing monoclonal antibodies (mAb) possess considerable efficacy, their current reliance on parenteral dosing necessitates very large doses and places a substantial burden on the healthcare system. In contrast, direct inhaled delivery of mAb therapeutics offers the convenience of self-dosing at home, as well as much more efficient mAb delivery to the respiratory tract. Here, building on our previous discovery of Fc-mucin interactions crosslinking viruses to mucins, we showed that regdanvimab, a potent neutralizing mAb already approved for COVID-19 in several countries, can effectively trap SARS-CoV-2 virus-like particles in fresh human airway mucus. IN-006, a reformulation of regdanvimab, was stably nebulized across a wide range of concentrations, with no loss of activity and no formation of aggregates. Finally, nebulized delivery of IN-006 resulted in 100-fold greater mAb levels in the lungs of rats compared to serum, in marked contrast to intravenously dosed mAbs. These results not only support our current efforts to evaluate the safety and efficacy of IN-006 in clinical trials, but more broadly substantiate nebulized delivery of human antiviral mAbs as a new paradigm in treating SARS-CoV-2 and other respiratory pathologies.

MircroRNA Let-7a-5p in Airway Smooth Muscle Cells is Most Responsive to High Stretch in Association With Cell Mechanics Modulation

Objective: High stretch (strain >10%) can alter the biomechanical behaviors of airway smooth muscle cells which may play important roles in diverse lung diseases such as asthma and ventilator-induced lung injury. However, the underlying modulation mechanisms for high stretch-induced mechanobiological responses in ASMCs are not fully understood. Here, we hypothesize that ASMCs respond to high stretch with increased expression of specific microRNAs (miRNAs) that may in turn modulate the biomechanical behaviors of the cells. Thus, this study aimed to identify the miRNA in cultured ASMCs that is most responsive to high stretch, and subsequently investigate in these cells whether the miRNA expression level is associated with the modulation of cell biomechanics.

Methods: MiRNAs related to inflammatory airway diseases were obtained via bioinformatics data mining, and then tested with cultured ASMCs for their expression variations in response to a cyclic high stretch (13% strain) simulating in vivo ventilator-imposed strain on airways. Subsequently, we transfected cultured ASMCs with mimics and inhibitors of the miRNA that is most responsive to the high stretch, followed by evaluation of the cells in terms of morphology, stiffness, traction force, and mRNA expression of cytoskeleton/focal adhesion-related molecules.

Results: 29 miRNAs were identified to be related to inflammatory airway diseases, among which let-7a-5p was the most responsive to high stretch. Transfection of cultured human ASMCs with let-7a-5p mimics or inhibitors led to an increase or decrease in aspect ratio, stiffness, traction force, migration, stress fiber distribution, mRNA expression of α-smooth muscle actin (SMA), myosin light chain kinase, some subfamily members of integrin and talin. Direct binding between let-7a-5p and ItgαV was also verified in classical model cell line by using dual-luciferase assays.

Conclusion: We demonstrated that high stretch indeed enhanced the expression of let-7a-5p in ASMCs, which in turn led to changes in the cells’ morphology and biomechanical behaviors together with modulation of molecules associated with cytoskeletal structure and focal adhesion. These findings suggest that let-7a-5p regulation is an alternative mechanism for high stretch-induced effect on mechanobiology of ASMCs, which may contribute to understanding the pathogenesis of high stretch-related lung diseases.

Efficacy and safety of acetylcysteine for the prevention of liver injury in COVID-19 intensive care unit patients under treatment with remdesivir

AIM

The present double-blinded placebo-controlled randomized clinical trial evaluated prophylactic use of acetylcysteine for the prevention of liver injury in patients with severe COVID-19 pneumonia under treatment with remdesivir.

BACKGROUND

Liver injury is reportedly common in patients with severe COVID-19 pneumonia and can occur not only as a result of disease progression, but as an iatrogenic reaction to remdesivir.

METHODS

A total of 83 adult patients with severe COVID-19 pneumonia were randomly assigned in parallel groups to receive either acetylcysteine or placebo. All the patients received standard care according to institutional protocols, including remdesivir for a total of five days. One gram acetylcysteine was administered intravenously every 12 hours for 42 patients, and 41 patients received the same volume of 0.9% sodium chloride as placebo (Trial Registration: www.irct.ir identifier, IRCT20210726051995N1).

RESULTS

After 5 days, median aspartate transaminase (AST) and alanine transaminase (ALT) levels were significantly lower in the acetylcysteine than in the placebo group. Of those who received the placebo, 30 (73.2%), 4 (9.7%), and 3 (7.3%) patients had serum AST levels elevated between 1-2.5, 2.5-5, and over 5 times the upper limit of normal (ULN), respectively; while in the acetylcysteine group, 33 (78.6%) and 0 patients had AST levels between 1-2.5 and over 2.5 times ULN, respectively (p-value=0.037). In the acetylcysteine group, 23 (54.8%), 1 (2.4%), and 1 (2.4%) patient had serum ALT levels elevated between 1-2.5, 2.5-5, and over 5 times ULN, respectively; in the placebo group, however, 24 (58.5%), 7 (17.1%), and 1 (2.4%) patient had serum ALT levels between 1-2.5, 2.5-5, and over 5 times ULN, respectively (p-value=0.073).

CONCLUSION

Intravenous administration of acetylcysteine significantly prevents liver transaminases elevation and liver injury in seriously ill COVID-19 patients treated with remdesivir.

Unanticipated demand of Physiotherapist-Deployed Airway Clearance during the COVID-19 Surge 2020 a single centre report

Bronchial secretion management was not an anticipated clinical problem in patients intubated and ventilated with COVID-19. Yet 63 (62%) of our intubated and ventilated patients demonstrated a moderate or greater sputum load, as recorded by physiotherapists on 5 or more days of the patient's ICU stay. The efficacy of airway clearance in these patients was further compounded by ineffective or absent cough and increased secretion tenacity, dramatically increasing the workload of critical care physiotherapists. We provide data to support the modelling of critical care physiotherapy staffing for future COVID-19 surges.

[Mucociliary clearance in COVID-19 - an underestimated danger area in early phase of disease?]

BACKGROUND

As with other inflammatory diseases, the (dry) cough in COVID-19 patients indicates that mucociliary clearance (MCC) is at least at risk, if not overloaded, damaged or largely inoperable. Coughing is an important secondary mechanism that only takes over bronchial cleansing as a replacement if the MCC has failed.

METHOD

The review article describes the physiology and pathophysiology of MCC and its possible role in the pathogenesis of COVID-19.

RESULTS AND CONCLUSIONS

Human and animal studies as well as autopsy reports indicate that MCC could also be important for the COVID-19 pathogenesis. In primary care, MCC plays a major role in inflammatory respiratory diseases. In Germany, drugs for self-medication are approved for treatment and, due to the high quality of studies, are also recommended in the respective guidelines. A symptomatic approach to stabilize the airway barrier would also be conceivable in the early outpatient phase of COVID-19.

Ultraviolet-A light reduces cellular cytokine release from human endotracheal cells infected with Coronavirus

Background

An important clinical feature of coronavirus disease 2019 (COVID-19) is hypercytokinemia (cytokine storm). We previously showed that narrow band ultraviolet-A (NB-UVA) treatment salvages coronavirus (CoV)-229E-infected human tracheal cells, and that daily endotracheal NB-UVA therapy reduced severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) levels in human subjects, with improved clinical outcomes. Here, we examined NB-UVA effects on cytokine release during CoV-229E infection.

Methods

Primary human tracheal epithelial cells were transfected with CoV-229E, then exposed to 2 mW/cm² NB-UVA for 20 minutes every 24h, either 3 or 4 times. Secreted cytokine/chemokine levels were analyzed in supernatants collected from CoV-229E-infected/UVA-exposed cells 24h after the last UVA treatment, and from matched non-infected/UVA-exposed controls, CoV-229E-infected/non-exposed controls, and non-infected/non-exposed (naïve) controls. Metabolic pathway/downstream prediction analyses were also performed.

Results

Pro-inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF), and chemokines IL-8, monocyte chemoattractant protein-1 (MCP1), and interferon gamma-induced protein 10 (IP-10), were significantly increased in CoV-229E-infected cells, and significantly decreased following NB-UVA treatment. Interferon (IFN)-α2, IFN-γ, and IL-10 were not upregulated in response to CoV-229E. Metabolic pathway predictions indicated hypercytokinemia as the top inflammatory response in CoV-229E-infected cells, whereas the top predicted pathway in CoV-229E-infected/UVA-exposed cells was the recovery stage of severe acute respiratory syndrome.

Conclusions

Human tracheal epithelial cells infected with CoV-229E showed reduced cytokine secretions including IL-6, TNF, IL-8, and MCP-1, following NB-UVA exposure. This reduction of cytokine levels in vitro, coupled with previously identified reduced cell death in CoV-229E-infected/UVA-exposed cells, suggests that determining UVA effects on cytokine storm in human SARS-Co-V2 patients is warranted.

Nanotechnology to the Rescue: Treatment Perspective for the Immune Dysregulation Observed in COVID-19

The study of the use of nanotechnology for drug delivery has been extensive. Nanomedical approaches for therapeutics; drug delivery in particular is superior to conventional methods in that it allows for controlled targeted delivery and release, higher stability, extended circulation time, minimal side-effects, and improved pharmacokinetic clearance (of the drug) form the body, to name a few. The magnitude of COVID-19, the current ongoing pandemic has been severe; it has caused widespread the loss of human life. In individuals with severe COVID-19, immune dysregulation and a rampant state of hyperinflammation is observed. This kind of an immunopathological response is detrimental and results in rapid disease progression, development of secondary infections, sepsis and can be fatal. Several studies have pin-pointed the reason for this immune dysregulation; deviations in the signaling pathways involved in the mediation and control of immune responses. In severe COVID-19 patients, many signaling cascades including JAK/STAT, NF-κB, MAPK/ERK, TGF beta, VEGF, and Notch signaling were found to be either upregulated or inactivated. Targeting these aberrant signaling pathways in conjunction with antiviral therapy will effectuate mitigation of the hyperinflammation, hypercytokinemia, and promote faster recovery. The science of the use of nanocarriers as delivery agents to modulate these signaling pathways is not new; it has already been explored for other inflammatory diseases and in particular, cancer therapy. Numerous studies have evaluated the efficacy and potential of nanomedical approaches to modulate these signaling pathways and have been met with positive results. A treatment regime, that includes nanotherapeutics and antiviral therapies will prove effective and holds great promise for the successful treatment of COVID-19. In this article, we review different nanomedical approaches already studied for targeting aberrant signaling pathways, the host immune response to SARS-CoV-2, immunopathology and the dysregulated signaling pathways observed in severe COVID-19 and the current treatment methods in use for targeting signaling cascades in COVID-19. We then conclude by suggesting that the use of nanomedical drug delivery systems for targeting signaling pathways can be extended to effectively target the aberrant signaling pathways in COVID-19 for best treatment results.

The role of goblet cells in viral pathogenesis

Goblet cells are specialized epithelial cells that are essential to the formation of the mucus barriers in the airways and intestines. Armed with an arsenal of defenses, goblet cells can rapidly respond to infection but must balance this response with maintaining homeostasis. Whereas goblet cell defenses against bacterial and parasitic infections have been characterized, we are just beginning to understand their responses to viral infections. Here, we outline what is known about the enteric and respiratory viruses that target goblet cells, the direct and bystander effects caused by viral infection and how viral interactions with the mucus barrier can alter the course of infection. Together, these factors can play a significant role in driving viral pathogenesis and disease outcomes.

Cytokine Storm and Mucus Hypersecretion in COVID-19: Review of Mechanisms

Mucus is an integral part of the respiratory physiology. It protects the respiratory tract by acting as a physical barrier against inhaled particles and microbes. Excessive inflammation in conditions such as COVID-19 can result in over-production of mucus which obstructs the airway. Build-up of mucus can also contribute to recurrent airway infection, causing further obstruction. This article summarizes the current understanding and knowledge of respiratory mucus production and proposes the role of cytokine storm in inducing sudden mucus hypersecretion in COVID-19. Based on these cascades, the active constituents that inhibit or activate several potential targets are outlined for further research. These may be explored for the discovery and design of drugs to combat cytokine storm and its ensuing complications.

Is Persistent Thick Copious Mucus a Long-Term Symptom of COVID-19?

Introduction

The typical clinical picture of COVID-19 is gradually becoming clearer, both in the acute phase and in the long-term. However, new symptoms are gradually being identified. We describe a long-term symptom that has not yet been reported.

Case description

A 49-year-old man consulted for persistent asthenia. The general practitioner found a fever (39.2°C), and COVID-19 was confirmed by the polymerase chain reaction test. Further symptoms appeared, notably thick, white, painless tracheal hypersecretion for 3 months before diminishing, without disappearing.

Conclusion

Non-inflammatory tracheal hypersecretion, not yet reported in COVID-19, may be an additional long-term symptom. The hyperstimulation of tracheal goblet cells secreting mucus is 1 pathophysiological hypothesis.

LEARNING POINTS

Painless, non-inflammatory tracheal hypersecretion, which has yet to be described in post-acute COVID-19, may be an additional long-term symptom of the disease.The hyperstimulation of mucus-secreting tracheal goblet cells by the coronavirus, leading to tracheal discomfort and a feeling of suffocation, is 1 pathophysiological hypothesis.