Immunomodulatory approaches in managing lung inflammation in COVID-19: A double-edge sword

The comprehensive insights into the B-cells-mediated immune response against COVID-19 infection amid the ongoing evolution of SARS-CoV-2

The antibody-mediated immune response is crucial for the development of protective immunity against SARS-CoV-2, the virus responsible for the COVID-19 pandemic. Understanding the interaction between SARS-CoV-2 and the immune system is critical because new variants emerge as a result of the virus's ongoing evolution. Understanding the function of B cells in the SARS-CoV-2 infection process is critical for developing effective and long-lasting vaccines against this virus. Triggered by the innate immune response, B cells transform into memory B cells (MBCs). It is fascinating to observe how MBCs provide enduring immune defence, not only eradicating the infection but also safeguarding against future reinfection. If there is a lack of B cell activation or if the B cells are not functioning properly, it can lead to a serious manifestation of the disease and make immunisation less effective. Individuals with disruptions in the B cells have shown increased production of cytokines and chemokines, resulting in a poor prognosis for the disease. Therefore, we have developed an updated review article to gain insight into the involvement of B cells in SARS-CoV-2 infection. The discussion has covered the generation, functioning, and dynamics of neutralising antibodies (nAbs). Furthermore, we have emphasised immunotherapeutics that rely on nAbs.

IL-37 possesses both anti-inflammatory and antiviral effects against Middle East respiratory syndrome coronavirus infection

BACKGROUND

The aim was to elucidate the function of IL-37 in middle east respiratory syndrome coronavirus (MERS-CoV) infection, thereby providing a novel therapeutic strategy for managing the clinical treatment of inflammatory response caused by respiratory virus infection.

METHODS

We investigated the development of MERS by infecting hDPP4 mice with hCoV-EMC (107 TCID50 [50% tissue culture infectious dose]) intranasally. We infected A549 cells with MERS-CoV, which concurrently interfered with IL-37, detecting the viral titer, viral load, and cytokine expression at certain points postinfection. Meanwhile, we administered IL-37 (12.5 μg/kg) intravenously to hDPP4 mice 2 h after MERS-CoV-2 infection and collected the serum and lungs 5 days after infection to investigate the efficacy of IL-37 in MERS-CoV infection.

RESULTS

The viral titer of MERS-CoV-infected A549 cells interfering with IL-37 was significantly reduced by 4.7-fold, and the viral load of MERS-CoV-infected hDPP4 mice was decreased by 59-fold in lung tissue. Furthermore, the administration of IL-37 suppressed inflammatory cytokine and chemokine (monocyte chemoattractant protein 1, interferon-γ, and IL-17A) expression and ameliorated the infiltration of inflammatory cells in hDPP4 mice.

CONCLUSION

IL-37 exhibits protective properties in severe pneumonia induced by MERS-CoV infection. This effect is achieved through attenuation of lung viral load, suppression of inflammatory cytokine secretion, reduction in inflammatory cell infiltration, and mitigation of pulmonary injury.

Bronchoalveolar lavage single-cell transcriptomics reveals immune dysregulations driving COVID-19 severity

The continuous threats posed by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19, including the emergence of potentially more infectious and deadly variants, necessitate ongoing studies to uncover novel and detailed mechanisms driving disease severity. Using single-cell transcriptomics, we conducted a secondary data analysis of bronchoalveolar lavage fluid (BALF) from COVID-19 patients of varying severities and healthy controls to comprehensively examine immune responses. We observed significant immune cell alterations correlating with disease severity. In severe cases, macrophages showed upregulation of pro-inflammatory genes TNFα and IL1β, contributing to severe inflammation and tissue damage. Neutrophils exhibited increased activation, marked by S100A8, CXCL8, and IL1β expression, with extended viability and reduced phagocytosis. Genes such as MCL1 and HIF1α supported extended viability, while MSR1 and MRC1 indicated reduced phagocytosis. Enhanced formation of neutrophil extracellular traps (NETs) and reduced clearance, indicated by NET-associated markers, were linked to thrombo-inflammation and organ damage. Both macrophages and neutrophils in severe cases showed impaired efferocytosis, indicated by decreased expression of MSR1 and TREM2 in macrophages and downregulation of FCGR3B in neutrophils, leading to the accumulation of apoptotic cells and exacerbating inflammation. Severe cases were characterized by M1 macrophages with high TNFα and IL1β, while milder cases had M2 macrophages with elevated PPARγ. Dendritic cells (DCs) in severe cases exhibited reduced proportions and attenuated expression of MHC class I genes (HLA-A, HLA-B, HLA-C) and co-stimulatory molecules (CD80, CD86), alongside increased cytochrome c expression, indicating impaired antigen presentation and enhanced apoptosis. NK and T cells in severe cases demonstrated altered receptor and gene expression, with increased activation markers IFNγ and ISG15, suggesting a paradoxical state of activation and exhaustion. This analysis highlights the critical role of dysregulated neutrophil, macrophage, dendritic cell, NK, and T cell responses in severe COVID-19, identifying potential therapeutic targets and providing novel insights into the disease.

Antiviral effectiveness and safety of azvudine in hospitalized SARS‐CoV‐2 patients with pre‐existing chronic respiratory diseases: A multicenter, retrospective cohort study

Although azvudine has become a priority in the treatment of SARS‐CoV‐2, its effectiveness and safety among COVID‐19 patients who already have chronic respiratory diseases (CRDs) have not been sufficiently validated. A retrospective, multicenter cohort study involving 10 hospitals in Henan Province was performed to assess inpatients with COVID‐19 and CRDs (Clinical Trial Registration Number: NCT06349655). Azvudine recipients and the control group were matched at a 1:1 ratio using propensity scores. The clinical outcomes (all‐cause death and composite disease progression) were analyzed using Kaplan‒Meier and Cox regression analyses, with additional subgroup and sensitivity analyses performed. Eighteen clinical features were included to construct a nomogram for predicting the survival of inpatients with COVID‐19 and CRDs. Out of 37,606 hospitalized COVID‐19 patients, 1462 azvudine recipients and 1462 matched controls were included in the analysis. The results of Kaplan‒Meier and multivariate Cox regression analyses demonstrated that in contrast to the controls, azvudine use was associated with a decreased risk of all‐cause death in patients with COVID‐19 and pre‐existing CRDs (log‐rank: p = .012; HR: 0.73; 95% CI: 0.553‒0.956); but was not significantly different in terms of composite disease progression (log‐rank: p = .82; HR: 1.15; 95% CI: 0.948‒1.383). An analysis of subgroups and three sensitivity appraisals validate the above outcomes. The number and type of adverse events associated with azvudine treatment were acceptable. The concordance index (0.8499, 0.8497) and area under the curve (86.1%, 80.4%) of the nomogram showed satisfactory discriminative ability in the training and test sets. Azvudine could be effective in reducing all‐cause death among inpatients with COVID‐19 and CRDs and had few serious adverse events.

The role and therapeutic potential of itaconate in lung disease

Lung diseases triggered by endogenous or exogenous factors have become a major concern, with high morbidity and mortality rates, especially after the coronavirus disease 2019 (COVID-19) pandemic. Inflammation and an over-activated immune system can lead to a cytokine cascade, resulting in lung dysfunction and injury. Itaconate, a metabolite produced by macrophages, has been reported as an effective anti-inflammatory and anti-oxidative stress agent with significant potential in regulating immunometabolism. As a naturally occurring metabolite in immune cells, itaconate has been identified as a potential therapeutic target in lung diseases through its role in regulating inflammation and immunometabolism. This review focuses on the origin, regulation, and function of itaconate in lung diseases, and briefly discusses its therapeutic potential.

Multidrug Combinations against SARS-CoV-2 Using GS-441524 or Ivermectin with Molnupiravir and/or Nirmatrelvir in Reconstituted Human Nasal Airway Epithelia

Background. The emergence, global spread, and persistence of SARS-CoV-2 resulted in an unprecedented need for effective antiviral drugs. Throughout the pandemic, various drug development and treatment strategies were adopted, including repurposing of antivirals designed for other viruses along with a multitude of other drugs with varying mechanisms of action (MoAs). Furthermore, multidrug treatment against COVID-19 is an ongoing topic and merits further investigation. Method/Objectives. We assessed the efficacy of multidrug treatment against SARS-CoV-2 in reconstituted human nasal epithelia, using combinations of molnupiravir and nirmatrelvir as a baseline, adding suboptimal concentrations of either GS-441524 or ivermectin, attempting to increase overall antiviral activity while lowering the overall therapeutic dose. Results. Nirmatrelvir combined with molnupiravir, GS-441524, or ivermectin at suboptimal concentrations show increased antiviral activity compared to single treatment. No triple combinations showed improved inhibition of SARS-CoV-2 replication beyond what was observed for double treatments. Conclusions. In general, we observed that the addition of a third compound is not beneficial for antiviral activity, while various double combinations exhibit increased antiviral activity over single treatment.

Cytokine Profile in Patients with Postacute Sequelae of COVID-19

The enduring impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its disease manifestation, COVID-19, on public health remains significant. Postacute sequelae of SARS-CoV-2 infection (PASC) affect a considerable number of patients, impairing their quality of life. While the role of the cytokine storm in acute COVID-19 is well established, its contribution to the pathophysiology of PASC is not fully understood. This study aimed to analyze the cytokine profile of patients with PASC following in vitro stimulation of Toll-like receptor (TLR) pathways, comparing them with a healthy control group. From October 2020 till March 2021, Brugmann University Hospital's clinical research unit included patients with PASC in the study. Whole blood samples were collected from 50 patients and 25 healthy volunteers. After in vitro stimulation under five different conditions, cytokine levels were measured using a multiplex method. Significantly decreased cytokine levels were observed in patients with PASC compared with healthy volunteers, particularly after TLR4 (interleukin [IL]-1α, IL-1β, IL-2, IL-10, interferon (IFN)α, IFNγ, IFNω, and tumor necrosis factor (TNF)α) and TLR7/8 (IL-1α, IL-1β, IFNα, IFNω, IFNγ, and TNFα) pathway stimulation. Principal component analysis identified two distinct clusters, suggesting a likely dysregulation of immunity involving TLR4 and TLR7/8 pathways in patients with PASC. Our study suggests that TLR4 and TLR7/8 pathways play a role in the pathophysiology of PASC. Continuous basal activation of immunity could explain the high basal concentrations of cytokines described in these patients and the decreased amplitude of response of these signaling pathways following specific stimulation.

Using a static magnetic field to attenuate the severity in COVID-19-invaded lungs

Two important factors affecting the progress of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are the S-protein binding function of ACE2 receptors and the membrane fluidity of host cells. This study aimed to evaluate the effect of static magnetic field (SMF) on S-protein/ACE2 binding and cellular membrane fluidity of lung cells, and was performed in vitro using a Calu-3 cell model and in vivo using an animal model. The ability of ACE2 receptors to bind to SARS-CoV-2 spike protein on host cell surfaces under SMF stimulation was evaluated using fluorescence images. Host lung cell membrane fluidity was tested using fluorescence polarization to determine the effects of SMF. Our results indicate that 0.4 T SMF can affect binding between S-protein and ACE2 receptors and increase Calu-3 cell membrane fluidity, and that SMF exposure attenuates LPS-induced alveolar wall thickening in mice. These results may be of value for developing future non-contact, non-invasive, and low side-effect treatments to reduce disease severity in COVID-19-invaded lungs.

Harnessing immunity: Immunomodulatory therapies in COVID-19

An overly exuberant immune response, characterized by a cytokine storm and uncontrolled inflammation, has been identified as a significant driver of severe coronavirus disease 2019 (COVID-19) cases. Consequently, deciphering the intricacies of immune dysregulation in COVID-19 is imperative to identify specific targets for intervention and modulation. With these delicate dynamics in mind, immunomodulatory therapies have emerged as a promising avenue for mitigating the challenges posed by COVID-19. Precision in manipulating immune pathways presents an opportunity to alter the host response, optimizing antiviral defenses while curbing deleterious inflammation. This review article comprehensively analyzes immunomodulatory interventions in managing COVID-19. We explore diverse approaches to mitigating the hyperactive immune response and its impact, from corticosteroids and non-steroidal drugs to targeted biologics, including anti-viral drugs, cytokine inhibitors, JAK inhibitors, convalescent plasma, monoclonal antibodies (mAbs) to severe acute respiratory syndrome coronavirus 2, cell-based therapies (i.e., CAR T, etc.). By summarizing the current evidence, we aim to provide a clear roadmap for clinicians and researchers navigating the complex landscape of immunomodulation in COVID-19 treatment.

The mRNA-LNP vaccines - the good, the bad and the ugly?

The mRNA-LNP vaccine has received much attention during the COVID-19 pandemic since it served as the basis of the most widely used SARS-CoV-2 vaccines in Western countries. Based on early clinical trial data, these vaccines were deemed safe and effective for all demographics. However, the latest data raise serious concerns about the safety and effectiveness of these vaccines. Here, we review some of the safety and efficacy concerns identified to date. We also discuss the potential mechanism of observed adverse events related to the use of these vaccines and whether they can be mitigated by alterations of this vaccine mechanism approach.

COVID-19: A threat to the respiratory system

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), causes acute coronavirus disease-19 (COVID-19) that has emerged on a pandemic level. Coronaviruses are well-known to have a negative impact on the lungs and cardiovascular system. SARS-CoV-2 induces a cytokine storm that primarily targets the lungs, causing widespread clinical disorders, including COVID-19. Although, SARS-CoV-2 positive individuals often show no or mild upper respiratory tract symptoms, severe cases can progress to acute respiratory distress syndrome (ARDS). Novel CoV-2 infection in 2019 resulted in viral pneumonia as well as other complications and extrapulmonary manifestation. ARDS is also linked to a higher risk of death. Now, it is essential to develop our perception of the long term sequelae coronavirus infection for the identification of COVID-19 survivors who are at higher risk of developing the chronic lung fibrosis. This review study was planned to provide an overview of the effects of SARS-CoV-2 infection on various parts of the respiratory system such as airways, pulmonary vascular, lung parenchymal and respiratory neuromuscular system as well as the potential mechanism of the ARDS related respiratory complications including the lung fibrosis in patients with severe COVID-19.

Prognostic Factors and Outcomes in Advanced Stage Lung Cancer Patients with COVID-19 Omicron Variant Infection

Background

We study the characteristics and outcomes in lung cancer patients with COVID-19 Omicron variant infection.

Methods

Hospitalized lung cancer patients with advanced-stage disease and laboratory-confirmed COVID-19 Omicron infection were included. Pneumonitis involving at least 25% of lung parenchyma on CT scans, accompanied by symptoms and oxygen saturation below 93%, were criteria for enrollment. Pneumonitis severity was graded using CTCAE v5.0. Treatment included Paxlovid, prednisolone, anticoagulation, and ventilation. Initial data, radiographic findings, and outcomes were compared. Logistic regression was employed to determine risk factors for in-hospital mortality.

Results

Fifteen patients (median age: 65 years; 80.0% males) were included. 73.3% improved and were discharged, 20.0% died, and 6.7% remained intubated. Initial symptoms included cough (100.0%), fever (73.3%), and shortness of breath (53.3%). Symptoms resolved in discharged patients. Median fever duration was 3.5 days, and respiratory symptom recovery took 26 days. Three patients died due to respiratory failure from Omicron pneumonia. Lower oxygen saturation, reduced lymphocyte/neutrophil ratio on day 7, and diffuse bilateral lung lesions were poor prognostic factors.

Conclusion

This study underscores the importance of prompt intervention and early diagnosis for lung cancer patients infected with the COVID-19 Omicron variant. Lower oxygen saturation, decreased lymphocyte/neutrophil ratio on day 7, and diffuse lung lesions on CT scans were associated with worse outcomes. Clinicians should prioritize timely and comprehensive management to improve survival rates in this population.

Association of hypernatremia with mortality in patients with COVID-19: A systematic review and meta-analysis

BACKGROUND

The COVID-19 pandemic worldwide has caused varying degrees of severity of lung damage in patients, with acute respiratory distress and death in severe cases. However, this is not directly caused by the virus itself, but by the production of inflammasome by monocytes in the body, leading to a systemic inflammatory response, which results in a very poor clinical prognosis for patients with COVID-19.

OBJECTIVE

The purpose of this meta-analysis was to look at the relationship between hypernatremia and mortality in COVID-19 patients.

METHODS

We searched the PubMed, Web of Science, Embase, and Cochrane databases for articles published from the inception of the database until August 27, 2022. Three researchers reviewed the literature, retrieved data, and assessed the quality of the literature, respectively. A meta-analysis was performed using State 17 software to assess the value of the effect of hypernatremia on mortality in patients with new coronavirus pneumonia.

RESULTS

A total of nine publications was finally included in this study, including a total of 11,801 patients with COVID-19, including 1278 in the hypernatremia group and 10,523 in the normonatremia group. Meta-analysis showed that hypernatremia was associated with mortality in patients with COVID-19 [OR = 4.15, 95% CI (2.95-5.84), p = .002, I² = 66.7%] with a sensitivity of 0.36 [0.26, 0.48] and a specificity of 0.88 [0.83, 0.91]. The posterior probability of mortality was 42% in patients with COVID-19 hypernatremia and 15% in patients who did not have COVID-19 hypernatremia.

CONCLUSION

According to available data, hypernatremia is associated with death in patients with COVID-19.