IL-4/IL-13 remodeling pathway of COVID-19 lung injury

The association between COVID-19 vaccine/infection and new-onset asthma in children - based on the global TriNetX database

INTRODUCTION

The COVID-19 pandemic has underscored the importance of its potential long-term health effects, including its link to new-onset asthma in children. Asthma significantly impacts children's health, causing adverse outcomes and increased absenteeism. Emerging evidence suggests a potential association between COVID-19 infection and higher rates of new-onset asthma in adults, raising concerns about its impact on children's respiratory health.

METHODS

A retrospective cohort study design was employed, using electronic medical records from the TriNetX database, covering January 1, 2021, to December 31, 2022. Two cohorts of children aged 5 to 18 who underwent SARS-CoV-2 RT-PCR testing were analyzed: unvaccinated children with and without COVID-19 infection, and vaccinated children with and without infection. Propensity score matching was used to mitigate selection bias, and hazard ratio (HR) and 95% CI were calculated to assess the risk of new-onset asthma.

RESULTS

Our study found a significantly higher incidence of new-onset asthma in COVID-19 infected children compared to uninfected children, regardless of vaccination status. In Cohort 1, 4.7% of COVID-19 infected children without vaccination developed new-onset asthma, versus 2.0% in their non-COVID-19 counterparts within a year (HR = 2.26; 95% CI = 2.158-2.367). For Cohort 2, COVID-19 infected children with vaccination showed an 8.3% incidence of new-onset asthma, higher than the 3.1% in those not infected (HR = 2.745; 95% CI = 2.521-2.99). Subgroup analyses further identified higher risks in males, children aged 5-12 years, and Black or African American children. Sensitivity analyses confirmed the reliability of these findings.

CONCLUSION

The study highlights a strong link between COVID-19 infection and an increased risk of new-onset asthma in children, which is even more marked in those vaccinated. This emphasizes the critical need for ongoing monitoring and customized healthcare strategies to mitigate the long-term respiratory impacts of COVID-19 in children, advocating for thorough strategies to manage and prevent asthma amidst the pandemic.

Dysregulated Leukotriene Metabolism in Patients with COVID-19

This study aimed to examine the leukotriene metabolism during COVID-19. In total, 180 participants were included in this study, of which 60 were healthy controls, 60 required intensive care units (ICU), and 60 did not require intensive care (non-ICU). The serum levels of 5-lipoxygenase (5-LO), 5-LO activating protein (ALOX5AP), and cysteinyl leukotriene (CYSLT) were measured, and the mRNA expression levels of 5-LO, ALOX5AP, and cysteinyl leukotriene receptor 1 (CYSLTR1) were investigated. Compared with the control group, both the non-ICU and ICU groups had lower levels of 5-LO and mRNA expression. ICU patients had lower levels of 5-LO and mRNA expression than non-ICU patients. CYSLTR1 mRNA expression was highest in the ICU group, followed by the non-ICU group, and healthy controls had the lowest mRNA expression levels. CYSLT levels were higher in the control group than in the non-ICU and ICU groups. CYSLTR1 expression was higher in patients than in controls; therefore, selective leukotriene receptor blockers can be used as treatment options. CYSLTR1 expression was higher in the ICU group than in the non-ICU group. Furthermore, CYSLTR1 mRNA expression may be a promising biomarker of COVID-19 severity.

Stimuli-Mediated Macrophage Switching, Unraveling the Dynamics at the Nanoplatforms-Macrophage Interface

Macrophages play an essential role in immunotherapy and tissue regeneration owing to their remarkable plasticity and diverse functions. Recent bioengineering developments have focused on using external physical stimuli such as electric and magnetic fields, temperature, and compressive stress, among others, on micro/nanostructures to induce macrophage polarization, thereby increasing their therapeutic potential. However, it is difficult to find a concise review of the interaction between physical stimuli, advanced micro/nanostructures, and macrophage polarization. This review examines the present research on physical stimuli-induced macrophage polarization on micro/nanoplatforms, emphasizing the synergistic role of fabricated structure and stimulation for advanced immunotherapy and tissue regeneration. A concise overview of the research advancements investigating the impact of physical stimuli, including electric fields, magnetic fields, compressive forces, fluid shear stress, photothermal stimuli, and multiple stimulations on the polarization of macrophages within complex engineered structures, is provided. The prospective implications of these strategies in regenerative medicine and immunotherapeutic approaches are highlighted. This review will aid in creating stimuli-responsive platforms for immunomodulation and tissue regeneration.

A cell-adapted SARS-CoV-2 mutant, showing a deletion in the spike protein spanning the furin cleavage site, has reduced virulence at the lung level in K18-hACE2 mice

Here we investigated the virulence properties of a unique cell-adapted SARS-CoV-2 mutant showing a ten-amino acid deletion encompassing the furin cleavage site of the spike protein (Δ680SPRAARSVAS689; Δ680-689-B.1) in comparison to its parental strain (wt-B.1) and two Delta variants (AY.122 and AY.21) of concern. After intranasal inoculation, transgenic K18-hACE2 mice were monitored for 14 days for weight change, lethality, and clinical score; oral swabs were daily collected and tested for the presence of N protein subgenomic RNA. At 3 and 7 dpi mice were also sacrificed and organs collected for molecular, histopathological, and immune response profile investigations. The Δ680-689-B.1-infected mice exhibited reduced shedding, lower virulence at the lung level, and milder pulmonary lesions. In the lung, infection with Δ680-689-B.1 was associated with a significant lower expression of some cytokines at 3 dpi (IL-4, IL-27, and IL-28) and 7 dpi (IL-4, IL-27, IL-28, IFN-γ and IL-1α).

Features of Appendix and the Characteristics of Appendicitis Development in Children with COVID-19

BACKGROUND

Research on the subject of the influence of SARS-CoV-2 mechanisms on human homeostasis remains an actual problem. Particular interest is the study of pathomorphological changes in the appendix in children with COVID-19.

OBJECTIVES

Aim of this study: morphological and molecular biological evaluation of the appendix in children of different age groups with COVID-19.

METHODS

Groups were formed on the basis of anamnestic, clinical, and morphological data: I (n = 42; aged 2 to 18 years, average age-10.8 ± 4.79)-with an established clinical diagnosis: coronavirus infection (COVID-19; PCR+); II (n = 55; aged 2 to 18 years, average age-9.7 ± 4.77)-with a confirmed clinical diagnosis of acute appendicitis; collected before the onset of the COVID-19 pandemic in 2017-2019; and III (n = 38; aged 2 to 18 years, average age-10.3 ± 4.62)-the control group. Histological and immunohistochemical studies were conducted using primary antibodies to CD3, CD4, CD68, CD163, CD20, and CD138 and to pro-inflammatory (IL-1, IL-6) and anti-inflammatory (IL-4, IL-10) cytokines.

RESULTS

In most samples of appendixes in children with COVID-19, signs of destructive phlegmonous-ulcerative and gangrenous appendicitis were discovered. An increase in CD3+, CD4+, CD68+, CD163+, and CD20+ CD138+ immunocompetent cells was found in the appendix of children with COVID-19. As well, there was an increase in pro-inflammatory (IL-1, IL-6) and anti-inflammatory (IL-4, IL-10) cytokines.

CONCLUSIONS

The aforementioned pathological and immunohistochemical changes were more pronounced in the group of children aged 6-12 years (childhood).

Pro-Inflammatory and Anti-Inflammatory Interleukins in Infectious Diseases: A Comprehensive Review

Interleukins (ILs) are signaling molecules that are crucial in regulating immune responses during infectious diseases. Pro-inflammatory ILs contribute to the activation and recruitment of immune cells, whereas anti-inflammatory ILs help to suppress excessive inflammation and promote tissue repair. Here, we provide a comprehensive overview of the role of pro-inflammatory and anti-inflammatory ILs in infectious diseases, with a focus on the mechanisms underlying their effects, their diagnostic and therapeutic potential, and emerging trends in IL-based therapies.

Suppressed transcript diversity and immune response in COVID-19 ICU patients: a longitudinal study

Understanding the dynamic changes in gene expression during Acute Respiratory Distress Syndrome (ARDS) progression in post-acute infection patients is crucial for unraveling the underlying mechanisms. Study investigates the longitudinal changes in gene/transcript expression patterns in hospital-admitted severe COVID-19 patients with ARDS post-acute SARS-CoV-2 infection. Blood samples were collected at three time points and patients were stratified into severe and mild ARDS, based on their oxygenation saturation (SpO2/FiO2) kinetics over 7 d. Decline in transcript diversity was observed over time, particularly in patients with higher severity, indicating dysregulated transcriptional landscape. Comparing gene/transcript-level analyses highlighted a rather limited overlap. With disease progression, a transition towards an inflammatory state was evident. Strong association was found between antibody response and disease severity, characterized by decreased antibody response and activated B cell population in severe cases. Bayesian network analysis identified various factors associated with disease progression and severity, viz. humoral response, TLR signaling, inflammatory response, interferon response, and effector T cell abundance. The findings highlight dynamic gene/transcript expression changes during ARDS progression, impact on tissue oxygenation and elucidate disease pathogenesis.

Cytokines as drivers: Unraveling the mechanisms of epithelial-mesenchymal transition in COVID-19 lung fibrosis

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), like other viruses, can induce proliferation of myofibroblasts and even lead to fibrosis in the lung. Epithelial-mesenchymal transition (EMT) is thought to play an essential role in the pathogenesis of Coronavirus disease 19 (COVID-19). EMT is originally a critical process that regulates the development of different tissues in the embryo, but in inflammatory situations, EMT tries to be activated again to control inflammation or even heal inflammatory damage. However, in pathological situations, such as chronic viral infections (e.g., COVID-19) or pulmonary fibrosis initiation, this benign healing transforms into sinister nature, pushing the lung into the fibrotic process. Notably, the cytokines released by inflammatory cells and the chronic inflammatory microenvironment shared by fibrotic cells promote each other as critical factors in the induction of pathological EMT. In the induction of SARS-CoV-2 virus, cytokines are an essential mediator of EMT transformation, and a summary of whether COVID-19 patients, during the infection phase, have many persistent inflammatory mediators (cytokines) that are a causative factor of EMT has not yet appeared. The following common signaling drivers, including Transforming growth factor beta (TGF-β), cytokines, Notch signaling pathway, Wnt and hypoxia signaling pathways, drive the regulation of EMT. In this review, we will focus on 3 key EMT signaling pathways: TGF-β, Leucine zipper transcription factor like 1 (LZTFL1) and the common interleukin family expressed in the lung. TGF-β-induced SNAIL and LZTFL1 were identified as regulatory EMT in COVID-19. For cytokines, the interleukin family is a common inducer of EMT and plays an essential role in the formation of the microenvironment of fibrosis. We sought to demonstrate that cytokines act as "communicators" and build the "microenvironment" of fibrosis together with EMT as a "bridge" to induce EMT in fibrosis. The mechanisms utilized by these two pathways could serve as templates for other mesenchymal transformations and provide new potential therapeutic targets.

Spatiotemporal observations of host-pathogen interactions in mucosa during SARS-CoV-2 infection indicate a protective role of ILC2s

IMPORTANCE

Our study revealed the spatial interaction between humanized ACE2 and pseudovirus expressing Spike, emphasizing the role of type 2 innate lymphoid cells during the initial phase of viral infection. These findings provide a foundation for the development of mucosal vaccines and other treatment approaches for both pre- and post-infection management of coronavirus disease 2019.

Omicron induced distinct immune respiratory transcriptomics signatures compared to pre-existing variants in critically ill COVID-19 patients

Severe coronavirus disease 2019 (COVID-19) is related to dysregulated immune responses. We aimed to explore the effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants on the immune response by nasopharyngeal transcriptomic in critically-ill patients. This prospective monocentric study included COVID-19 patients requiring intensive care unit (ICU) admission between March 2020 and 2022. Patients were classified according to VOC (ancestral, Alpha, Delta, and Omicron). Eighty-eight patients with severe COVID-19 were included after matching (on prespecified clinical criteria). Profiling of gene expression markers of innate and adaptive immune responses were investigated by respiratory transcriptomics at ICU admission. Eighty-eight patients were included in the study after matching (ancestral [n = 24], Alpha [n = 24], Delta [n = 22], and Omicron [n = 18] variants). Respiratory transcriptomic analysis revealed distinct innate and adaptive immune profiling between variants. In comparison with the ancestral variant, there was a reduced expression of neutrophil degranulation, T cell activation, cytokines signalling pathways in patients infected with Alpha and Delta variants. In contrast, there was a higher expression of neutrophil degranulation, T and B cells activation, and inflammatory interleukins pathways in patients infected with Omicron. To conclude, Omicron induced distinct immune respiratory transcriptomics signatures compared to pre-existing variants in patients with severe COVID-19, pointing to an evolving pathophysiology of severe COVID-19 in the Omicron era.

Identifying the Interaction Between Tuberculosis and SARS-CoV-2 Infections via Bioinformatics Analysis and Machine Learning

The number of patients with COVID-19 caused by severe acute respiratory syndrome coronavirus 2 is still increasing. In the case of COVID-19 and tuberculosis (TB), the presence of one disease affects the infectious status of the other. Meanwhile, coinfection may result in complications that make treatment more difficult. However, the molecular mechanisms underpinning the interaction between TB and COVID-19 are unclear. Accordingly, transcriptome analysis was used to detect the shared pathways and molecular biomarkers in TB and COVID-19, allowing us to determine the complex relationship between COVID-19 and TB. Two RNA-seq datasets (GSE114192 and GSE163151) from the Gene Expression Omnibus were used to find concerted differentially expressed genes (DEGs) between TB and COVID-19 to identify the common pathogenic mechanisms. A total of 124 common DEGs were detected and used to find shared pathways and drug targets. Several enterprising bioinformatics tools were applied to perform pathway analysis, enrichment analysis and networks analysis. Protein-protein interaction analysis and machine learning was used to identify hub genes (GAS6, OAS3 and PDCD1LG2) and datasets GSE171110, GSE54992 and GSE79362 were used for verification. The mechanism of protein-drug interactions may have reference value in the treatment of coinfection of COVID-19 and TB.

Trained immunity of alveolar macrophages enhances injury resolution via KLF4-MERTK-mediated efferocytosis

Recent studies suggest that training of innate immune cells such as tissue-resident macrophages by repeated noxious stimuli can heighten host defense responses. However, it remains unclear whether trained immunity of tissue-resident macrophages also enhances injury resolution to counterbalance the heightened inflammatory responses. Here, we studied lung-resident alveolar macrophages (AMs) prechallenged with either the bacterial endotoxin or with Pseudomonas aeruginosa and observed that these trained AMs showed greater resilience to pathogen-induced cell death. Transcriptomic analysis and functional assays showed greater capacity of trained AMs for efferocytosis of cellular debris and injury resolution. Single-cell high-dimensional mass cytometry analysis and lineage tracing demonstrated that training induces an expansion of a MERTKhiMarcohiCD163+F4/80low lung-resident AM subset with a proresolving phenotype. Reprogrammed AMs upregulated expression of the efferocytosis receptor MERTK mediated by the transcription factor KLF4. Adoptive transfer of these trained AMs restricted inflammatory lung injury in recipient mice exposed to lethal P. aeruginosa. Thus, our study has identified a subset of tissue-resident trained macrophages that prevent hyperinflammation and restore tissue homeostasis following repeated pathogen challenges.

The Important Role of Interleukin-2 in COVID-19

There is controversial literature about the effects of the interleukin-2 (IL-2) cytokine family in COVID-19 pathogenesis and immunity. So we aimed to identify the potential in the role of the IL-2 family in COVID-19. A narrative review search was done through online databases, including PubMed, Scopus, and Web of Science. The search deadline was up to December 2022. We applied no time limits for the searching strategy. After retrieving articles from the databases, the authors summarized the data into two data extraction tables. The first data extraction table described the changes in the IL-2 cytokine family in COVID-19 and the second table described the therapeutic interventions targeting IL-2 family cytokines. The results of the literature on the role of the IL-2 cytokine family do not show a singular rule. IL-2 cytokine family can change during severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Some studies suggest that IL-2 cytokine family rise during the infection and cause severe inflammatory response and cytokine storm. These cytokines are shown to be increased in immunocompromised patients and worsen their prognosis. In individuals without underlying disease, the upregulation of the IL-2 family shows the clinical outcome of the disease and rises with disease severity. However, some other studies show that these cytokines do not significantly change. IL-2 cytokine family is mostly upregulated in healthy individuals who had vaccination, but immunocompromised patients did not show significant changes after a single dose of vaccines, which shows that these patients need booster doses for efficient immunity. IL-2 cytokine family can also be used as immunotherapy agents in COVID-19.

Airway Epithelial-Derived Immune Mediators in COVID-19

The airway epithelium, which lines the conducting airways, is central to the defense of the lungs against inhaled particulate matter and pathogens such as SARS-CoV-2, the virus that causes COVID-19. Recognition of pathogens results in the activation of an innate and intermediate immune response which involves the release of cytokines and chemokines by the airway epithelium. This response can inhibit further viral invasion and influence adaptive immunity. However, severe COVID-19 is characterized by a hyper-inflammatory response which can give rise to clinical presentations including lung injury and lead to acute respiratory distress syndrome, viral pneumonia, coagulopathy, and multi-system organ failure. In response to SARS-CoV-2 infection, the airway epithelium can mount a maladaptive immune response which can delay viral clearance, perpetuate excessive inflammation, and contribute to the pathogenesis of severe COVID-19. In this article, we will review the barrier and immune functions of the airway epithelium, how SARS-CoV-2 can interact with the epithelium, and epithelial-derived cytokines and chemokines and their roles in COVID-19 and as biomarkers. Finally, we will discuss these immune mediators and their potential as therapeutic targets in COVID-19.

Serum profiles of pro-inflammatory and anti-inflammatory cytokines in non-hospitalized patients with mild/moderate COVID-19 infection

This study attempted to explore pro-inflammatory and anti-inflammatory responses in patients with mild/moderate coronavirus disease 19 (COVID-19). Eight pro-inflammatory (IL-1α, IL-1β, IL-12, IL-17A, IL-17E, IL-31, IFN-γ and TNF-α) and three anti-inflammatory (IL-1Ra, IL-10 and IL-13) cytokines, as well as two chemokines (CXCL9 and CXCL10), were analyzed in the serum from ninety COVID-19 patients and healthy controls. Cytokine/chemokine levels were measured using enzyme-linked immunosorbent assay kits. Results revealed that IL-1α, IL-1β, IL-10, IL-12, IL-13, IL-17A, IL-31, IFN-γ, TNF-α and CXCL10 were significantly higher in patients than in controls, while IL-1Ra levels were significantly lower in patients. IL-17E and CXCL9 levels showed no significant differences between patients and controls. Seven cytokines/chemokines recorded an area under the curve greater than 0.8: IL-12 (0.945), IL-17A (0.926), CXCL10 (0.909), IFN-γ (0.904), IL-1α (0.869), TNF-α (0.825) and IL-10 (0.821). As indicated by the odds ratio, elevated levels of nine cytokines/chemokines were associated with an increased risk of COVID-19: IL-1α (19.04), IL-10 (5.01), IL-12 (43.66), IL-13 (4.25), IL-17A (16.62), IL-31 (7.38), IFN-γ (13.55), TNF-α (12.00) and CXCL10 (11.18). Only one positive (IL-17E with TNF-α) and six negative (IL-1β, IL-17A and IL-17E with CXCL9, IL-10 with IL-17A, and IL-1β and IL-17A with CXCL10) correlations were found between these cytokines/chemokines. In conclusion, pro-inflammatory (IL-1α, IL-1β, IL-12, IL-13, IL-17A, IL-31, IFN-γ, TNF-α and CXCL10) and anti-inflammatory (IL-10 and IL-13) cytokines/chemokines were up-regulated in the serum of patients with mild/moderate COVID-19. Their potential as biomarkers for diagnosis and prognosis is suggested and the association with COVID-19 risk is indicated to give more insight on COVID-19 immunological responses among non-hospitalized patients.

The role of interleukin 13 and the type 2 immune pathway in COVID-19: A review

Although much has been learned about severe acute respiratory syndrome coronavirus 2 since December 2019, uneven global vaccine distribution, rapid viral spread, and variant evasion of preventative measures have led to its persistence in the population for the foreseeable future. Additional therapies are needed to support patients through their acute, immune-mediated disease process that continues to lead to considerable morbidity and mortality. Data revealing the involvement of type 2 immune pathway in acute coronavirus disease 2019 and post-recovery conditions represent a potential additional area for intervention. Herein, we review the current understanding of interleukin 13 in acute severe acute respiratory syndrome coronavirus 2 infection, the clinical outcomes associated with type 2 immune processes, and the impact of type 2 blockade on acute and long-term coronavirus disease 2019 conditions.

Bone marrow mesenchymal stem cell-derived small extracellular vesicles promote liver regeneration via miR-20a-5p/PTEN

Balancing hepatocyte death and proliferation is key to non-transplantation treatments for acute liver failure (ALF), which has a high short-term mortality rate. Small extracellular vesicles (sEVs) may act as mediators in the repair of damaged liver tissue by mesenchymal stem cells (MSCs). We aimed to investigate the efficacy of human bone marrow MSC-derived sEVs (BMSC-sEVs) in treating mice with ALF and the molecular mechanisms involved in regulating hepatocyte proliferation and apoptosis. Small EVs and sEV-free BMSC concentrated medium were injected into mice with LPS/D-GalN-induced ALF to assess survival, changes in serology, liver pathology, and apoptosis and proliferation in different phases. The results were further verified in vitro in L-02 cells with hydrogen peroxide injury. BMSC-sEV-treated mice with ALF had higher 24 h survival rates and more significant reductions in liver injury than mice treated with sEV-free concentrated medium. BMSC-sEVs reduced hepatocyte apoptosis and promoted cell proliferation by upregulating miR-20a-5p, which targeted the PTEN/AKT signaling pathway. Additionally, BMSC-sEVs upregulated the mir-20a precursor in hepatocytes. The application of BMSC-sEVs showed a positive impact by preventing the development of ALF, and may serve as a promising strategy for promoting ALF liver regeneration. miR-20a-5p plays an important role in liver protection from ALF by BMSC-sEVs.

Vaccination increased host antiviral gene expression and reduced COVID-19 severity during the Omicron variant outbreak in Fuyang City, China

BACKGROUND

The differences in host antiviral gene expression and disease severity between vaccinated and non-vaccinated coronavirus disease 2019 (COVID-19) patients are not well characterized. We sought to compare the clinical characteristics and host antiviral gene expression patterns of vaccinated and non-vaccinated cohorts at the Second People's Hospital of Fuyang City.

METHODS

In this case-control study, we retrospectively analyzed 113 vaccinated patients with a COVID-19 Omicron variant infection, 46 non-vaccinated COVID-19 patients, and 24 healthy subjects (no history of COVID-19) recruited from the Second People's Hospital of Fuyang City. Blood samples were collected from each study participant for RNA extraction and PCR. We compared host antiviral gene expression profiles between healthy controls and COVID-19 patients who were either vaccinated or non-vaccinated at the time of infection.

RESULTS

In the vaccinated group, most patients were asymptomatic, with only 42.9 % of patients developing fever. Notably, no patients had extrapulmonary organ damage. In contrast, 21.4 % of patients in the non-vaccinated group developed severe/critical (SC) disease and 78.6 % had mild/moderate (MM) disease, with fever occurring in 74.2 % patients. We found that Omicron infection in COVID-19 vaccinated patients was associated with significantly increased expression of several important host antiviral genes including IL12B, IL13, CXCL11, CXCL9, IFNA2, IFNA1, IFNγ, and TNFα.

CONCLUSION

Vaccinated patients infected with the Omicron variant were mostly asymptomatic. In contrast, non-vaccinated patients frequently developed SC or MM disease. Older patients with SC COVID-19 also had a higher occurrence of mild liver dysfunction. Omicron infection in COVID-19 vaccinated patients was associated with the activation of key host antiviral genes and thus may play a role in reducing disease severity.

COVID-19-Associated Disease Course Is Shortened in Moderate-to-Severe Atopic Dermatitis Patients Receiving Dupilumab Treatment: A Retrospective Cross-Sectional Study

Previous studies suggest that allergic diseases may be a protective factor in SARS-CoV-2 infection. However, data regarding the impact of dupilumab, a widely used immunomodulatory medication, on COVID-19 in an allergic population are very limited. To investigate the incidence and severity of COVID-19 among moderate-to-severe atopic dermatitis (AD) patients treated with dupilumab, a retrospective cross-sectional survey was conducted among patients with moderate-to-severe AD who presented at the Department of Allergy of Tongji Hospital from 15 January 2023 to 31 January 2023. Healthy individuals matched for gender and age were also enrolled as a control. All subjects were asked about their demographic characteristics, past medical history, COVID-19 vaccination history, and medications, as well as the presence and duration of individual COVID-19-related symptoms. A total of 159 moderate-to-severe AD patients and 198 healthy individuals were enrolled in the study. Among the AD patients, 97 patients were treated with dupilumab, and 62 patients did not receive any biologicals or systemic treatments (topical treatment group). The proportions of people who were not infected with COVID in the dupilumab treatment group, topical treatment group and healthy control group were 10.31%, 9.68% and 19.19%, respectively (p = 0.057). There was no significant difference in COVID-19-related symptom scores among all groups (p = 0.059). The hospitalization rates were 3.58% in the topical treatment group and 1.25% in the healthy control group, and no patient was hospitalized in the dupilumab treatment group (p = 0.163). Compared with healthy control group and topical treatment group, the dupilumab treatment group had the shortest COVID-19-associated disease duration (dupilumab treatment group, 4.15 ± 2.85 d vs. topical treatment group, 5.43 ± 3.15 d vs. healthy control group, 6.09 ± 4.29 d; p = 0.001). Among the AD patients treated with dupilumab for different times, there was no appreciable difference (<0.5 year group, 5 ± 3.62 d vs. 0.5-1 year group, 4.84 ± 2.58 d vs. >1 year group, 2.8 ± 1.32 d; p = 0.183). Dupilumab treatment shortened the duration of COVID-19 in patients with moderate-to-severe AD. AD patients can continue their dupilumab treatment during the COVID-19 pandemic.

Exercise and COVID-19: exercise intensity reassures immunological benefits of post-COVID-19 condition

Any form of physical activity, including exercise, has various benefits at the physiological (improving cardiac and respiratory functions, increasing skeletal muscle mass, and maintaining homeostasis) and psychological levels (improving cognitive function, reducing anxiety and depression) which help to combat any type of infection. In contrast, the infectivity ratio could reduce the physical activity of an individual, such as performing a habitual exercise. Adaptation to different exercise strategies including intensity and duration may better increase physical performance and improve the symptoms. For example, low to moderate intensity perhaps fails to induce this adaptive process, while high-intensity of exercise compromises immune health. This can aggravate the infection rate (Open window theory). However, high intensity with a shorter time produces various morphological alterations in the primary organs including the lungs and heart, which facilitate life support in COVID-19 patients. However, less information about exercise protocols failed to assure the benefits of exercise to COVID-19 patients, particularly post-COVID-19 conditions. Therefore, this review will answer how exercise intensity is crucial to reassure the exercise benefits for promoting safe participation before infection and post-COVID-19 conditions.

COVID-19 and autoimmune diseases: is there a connection?

PURPOSE OF REVIEW

This review summarizes current evidence on the potential link between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and autoimmunity.

RECENT FINDINGS

Several viral infections are potential triggers of reactive and autoimmune diseases by inducing type II and type IV hypersensitivity reactions. Recent evidence demonstrated that SARS-CoV-2 infection is not an exception, triggering the production of tissue-specific autoantibodies during the acute phase of coronavirus disease 2019 (COVID-19) and leading to autoimmune diseases development as long-term complication. The significant immune dysregulation with cytokine storm and organ damage observed in patients with severe to critical COVID-19 is considered the main mechanism explaining the high levels of autoantibodies, which are also implicated in disease severity and the need for an intensive care assessment. Multisystem inflammatory syndrome in children (MIS-C) is an immune-mediated disease where the recent viral infection leads to systemic inflammation, as already observed in other reactive and autoimmune diseases.

SUMMARY

Autoimmunity may be a complication of SAR-CoV-2 infection. Understanding the pathogenesis of autoimmune manifestations in COVID-19 might help prevent the incidence or exacerbation of autoimmune disorders and design better and more efficient treatment strategies in children and adult populations.

Efficacy and safety of add-on Viola odorata L. in the treatment of COVID-19: A randomized double-blind controlled trial

ETHNOPHARMACOLOGICAL RELEVANCE

Severe Acute Respiratory Syndrome (SARS) due to the novel coronavirus has become the highest priority that threatens human health. This situation demands widespread vaccination and the innovation of new therapeutic methods. Despite drug discoveries, the need for approving new medicaments is felt because of adverse effects and lack of efficacy. Several medicinal plants including Viola odorata L. are recommended in traditional Persian medicine for alleviating respiratory infection symptoms. Recent studies showed anti-inflammatory, antioxidant, anti-asthmatic, antitussive, analgesic, and antibacterial activities of sweet violet. These enhance respiratory functions, reduce pulmonary inflammation, and decline mucous membrane edema. This study aimed to evaluate the efficacy of sweet violet syrup in alleviating the manifestations of COVID-19 infection.

MATERIAL AND METHODS

A randomized parallel-group double-blind controlled trial was conducted at Al-Zahra general hospital, Isfahan, Iran. A total of 108 outpatients were enrolled in the study. The patients were randomly allocated to intervention and placebo groups, with 54 patients in each group. The allocation was concealed using sealed opaque envelopes. The intervention group received violet syrup and the control group received placebo syrup, an add-on to the conventional treatment. The outcomes were COVID-19 manifestations, such as dyspnea, cough, myalgia, headache, and diarrhea, considered as outcomes of the study and were evaluated twice using a visual analog scale before the intervention and after 7 days, at the end of the study. Patients were followed daily by phone calls to monitor proper drug consumption and possible side effects.

RESULTS

No significant difference was between groups regarding demographic characteristics and vital signs before and after the treatment. Although all symptoms have improved significantly in both groups, patients who received violet syrup recovered faster and the mean severity scores of cough (P = 0.025), myalgia (P = 0.036), headache (P = 0.037), and diarrhea (P = 0.044) decreased greater in comparison to control group.

CONCLUSION

This study, the first clinical trial on the effectiveness of Viola odorata on SARS-CoV-2 patients, showed that Viola odorata L. effectively controls prevalent manifestations of COVID-19 including cough, myalgia, headache, and diarrhea. Regarding this survey, the violet syrup can be mentioned as a complementary treatment for viral influenza-like infections in which cough, myalgia, headache, and diarrhea are prominent.

Employing T-Cell Memory to Effectively Target SARS-CoV-2

Well-trained T-cell immunity is needed for early viral containment, especially with the help of an ideal vaccine. Although most severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected convalescent cases have recovered with the generation of virus-specific memory T cells, some cases have encountered T-cell abnormalities. The emergence of several mutant strains has even threatened the effectiveness of the T-cell immunity that was established with the first-generation vaccines. Currently, the development of next-generation vaccines involves trying several approaches to educate T-cell memory to trigger a broad and fast response that targets several viral proteins. As the shaping of T-cell immunity in its fast and efficient form becomes important, this review discusses several interesting vaccine approaches to effectively employ T-cell memory for efficient viral containment. In addition, some essential facts and future possible consequences of using current vaccines are also highlighted.

Age and Cytokine Gene Variants Modulate the Immunogenicity and Protective Effect of SARS-CoV-2 mRNA-Based Vaccination

The introduction of anti-SARS-CoV-2 vaccines in late 2020 substantially changed the pandemic picture, inducing effective protection in the population. However, individual variability was observed with different levels of cellular response and neutralizing antibodies. We report data on the impact of age, gender, and 16 single nucleotide polymorphisms (SNPs) of cytokine genes on the anti-SARS-CoV-2 IgG titers measured 31 and 105 days after administration of the second dose of BNT162b2 vaccine to 122 healthy subjects from the health care staff of the Palermo University Hospital, Italy. The higher titers at 31 days were measured in the younger subjects and in subjects bearing T-positive genotypes of IL-1R1 rs2234650 or the GG homozygous genotype of IL-6 rs1800795 SNP. T-positive genotypes are also significantly more common in subjects with higher titers at day 105. In addition, in this group of subjects, the frequency of the CT genotype of IL-4 rs2243250 is higher among those vaccinated with higher titers. Moreover, these SNPs and TNFA rs1800629 are differently distributed in a group of subjects that were found infected by SARS-CoV-2 at day 105 of evaluation. Finally, subjects that were found to be infected by SARS-CoV-2 at day 105 were significantly older than the uninfected subjects. Taken together, these data seem to suggest that age and polymorphisms of key cytokines, which regulate inflammation and humoral immune response, might influence the magnitude of the antibody response to vaccination with BNT162B2, prompting speculation about the possible benefit of a genetic background-based assessment of a personalized approach to the anti-COVID vaccination schedule.

Hyaluronan in the pathogenesis of acute and post-acute COVID-19 infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) recently emerged as the cause of a global pandemic. Infection with SARS-CoV-2 can result in COVID-19 with both acute and chronic disease manifestations that continue to impact many patients long after the resolution of viral replication. There is therefore great interest in understanding the host factors that contribute to COVID-19 pathogenesis. In this review, we address the role of hyaluronan (HA), an extracellular matrix polymer with roles in inflammation and cellular metabolism, in COVID-19 and critically evaluate the hypothesis that HA promotes COVID-19 pathogenesis. We first provide a brief overview of COVID-19 infection. Then we briefly summarize the known roles of HA in airway inflammation and immunity. We then address what is known about HA and the pathogenesis of COVID-19 acute respiratory distress syndrome (COVID-19 ARDS). Next, we examine potential roles for HA in post-acute SARS-CoV-2 infection (PASC), also known as "long COVID" as well as in COVID-associated fibrosis. Finally, we discuss the potential therapeutics that target HA as a means to treat COVID-19, including the repurposed drug hymecromone (4-methylumbelliferone). We conclude that HA is a promising potential therapeutic target for the treatment of COVID-19.

Potential long-term effects of SARS-CoV-2 infection on the pulmonary vasculature: Multilayered cross-talks in the setting of coinfections and comorbidities

The Coronavirus Disease 2019 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and its sublineages pose a new challenge to healthcare systems worldwide due to its ability to efficiently spread in immunized populations and its resistance to currently available therapies. COVID-19, although targeting primarily the respiratory system, is also now well established that later affects every organ in the body. Most importantly, despite the available therapy and vaccine-elicited protection, the long-term consequences of viral infection in breakthrough and asymptomatic individuals are areas of concern. In the past two years, investigators accumulated evidence on how the virus triggers our immune system and the molecular signals involved in the cross-talk between immune cells and structural cells in the pulmonary vasculature to drive pathological lung complications such as endothelial dysfunction and thrombosis. In the review, we emphasize recent updates on the pathophysiological inflammatory and immune responses associated with SARS-CoV-2 infection and their potential long-term consequences that may consequently lead to the development of pulmonary vascular diseases.

Immunomodulation Effect of Convalescent Plasma Therapy in Severe - Critical COVID-19 Patients

Introduction

Convalescent plasma therapy (CPT) is an alternative therapy for managing COVID-19, but its use is still controversial.

Objective

Analyzing the effectiveness of CPT in modulating immune responses based on SARS-COV-2 anti-spike protein receptor-binding domain (s-RBD) IgG, inflammatory cytokines (IL-6 and IL-4), and mortality in severe-critical COVID-19 patients.

Methods

This study was an observational analytical with a prospective cohort design. The number of participants was 39 patients from June to December 2020. The participants received CPT and was tested for blood analysis such as IL-4, IL-6 and s-RBD IgG. The data were taken a day before CPT, 1st day, 2nd day, and 7th day after CPT. The analysis included Friedman, Pearson correlation, and Mann-Whitney test which is significant if p <0.05.

Results

The value of participant's s-RBD IgG before CPT was 91.49 (0.43-3074.73) AU/mL and the 7th day post-CPT, s-RBD IgG value of 1169.79 (6.48-5577.91) AU/mL (p <0.001). The IL-4 value before CPT was 1.78 (0.85-5.21) ng/mL and the 7th day post-CPT, IL-4 value of 1.97 (0.87-120.30) ng/mL (p = 0.401). The condition was also found in IL-6 value, in which the IL-4 value participant before CPT was 109.61 (0.73-4701.63) ng/mL and the 7th day post-CPT, IL-6 value of 1.97 (0.87-120.30) ng/mL (p = 0.401). No significant correlation found between increased s-RBD IgG level with increased IL-4 and decreased IL-6 before and after CPT in severe-critical COVID-19 patients (p >0.05). No significant correlation was also found between increased s-RBD IgG levels, IL-4 too, and decreased IL-6 after CPT therapy between deceased and alive patients, both in 1st, 2nd, and 7th days (p >0.05).

Conclusion

No correlation between the increase in s-RBD IgG levels and changes in IL-4 and IL-6 levels. Changes in s-RBD IgG, IL-4, and IL-6 levels are not associated with mortality in severe-critical COVID-19 degree post CPT recipients.

Systems biology network reveals the correlation between COX-2 expression and Ch 7q copy number alterations in Ch 11q-deleted pediatric neuroblastoma tumors

Tumor-associated inflammation and chromosomal aberrations can play crucial roles in cancer development and progression. In neuroblastoma (NB), the enzyme cyclooxygenase-2 (COX-2) is associated with copy number alterations on the long arm of chromosome 11 (Ch 11q), defining an aggressive disease subset. This retrospective study included formalin-fixed paraffin-embedded tumor samples collected from nine patients during diagnosis at the pediatric Pequeno Principe Hospital, Curitiba, PR, Brazil, and post-chemotherapy (CT). COX-2 expression was evaluated using immunohistochemistry and correlated with the genome profile of paired pre- and post-CT samples, determined by array comparative genomic hybridization. A systems biology approach elucidated the PTGS2 network interaction. The results showed positive correlations between pre-CT Ch 7q gain and COX-2 expression (ρ = 0.825; p-value = 0.006) and negative correlations between Ch 7q gain and Ch 11q deletion (ρ = −0.919; p-value = 0.0005). Three samples showed Ch 11q deletion and Ch 7q gain. Network analysis identified a direct connection between CAV-1 (Ch 7q) and COX-2 in NB tumors and highlighted the connection between amplified genes in Ch 7q and deleted ones in 11q. The identification of hub-bottleneck-switch genes provides new biological insights into this connection between NB, tumorigenesis, and inflammation.

IL-13 determines specific IgE responses and SARS-CoV-2 immunity after mild COVID-19 and novel mRNA vaccination

After recovery, mild and severe COVID-19 diseases are associated with long-term effects on the host immune system, such as prolonged T-cell activation or accumulation of autoantibodies. In this study, we show that mild SARS-CoV-2 infections, but not SARS-CoV-2 spike mRNA vaccinations, cause durable atopic risk factors such as a systemic Th2- and Th17-type environment as well as activation of B cells responsive of IgE against aeroallergens from house dust mite and mold. At an average of 100 days post mild SARS-CoV-2 infections, anti-mold responses were associated with low IL-13 levels and increased pro-inflammatory IL-6 titers. Acutely severely ill COVID-19 patients instead showed no evidence of atopic reactions. Considering convalescents of mild COVID-19 courses and mRNA-vaccinated individuals together, IL-13 was the predominant significantly upregulated factor, likely shaping SARS-CoV-2 immunity. Application of multiple regression analysis revealed that the IL-13 levels of both groups were determined by the Th17-type cytokines IL-17A and IL-22. Taken together, these results implicate a critical role for IL-13 in the aftermath of SARS-CoV-2 mild infections and mRNA vaccinations, conferring protection against airway directed, atopic side reactions that occur in mildly experienced COVID-19.

Cytokine Profiling in Different SARS-CoV-2 Genetic Variants

This study is a successor of our previous work concerning changes in the chemokine profile in infection that are associated with different SARS-CoV-2 genetic variants. The goal of our study was to take into account both the virus and the host immune system by assessing concentrations of cytokines in patients infected with different SARS-CoV-2 variants (ancestral Wuhan strain, Alpha, Delta and Omicron). Our study was performed on 340 biological samples taken from COVID-19 patients and healthy donors in the timespan between May 2020 and April 2022. We performed genotyping of the virus in nasopharyngeal swabs, which was followed by assessment of cytokines' concentration in blood plasma. We noted that out of nearly 30 cytokines, only four showed stable elevation independently of the variant (IL-6, IL-10, IL-18 and IL-27), and we believe them to be 'constant' markers for COVID-19 infection. Cytokines that were studied as potential biomarkers lose their diagnostic value as the virus evolves, and the specter of potential targets for predictive models is narrowing. So far, only four cytokines (IL-6, IL-10, IL-18, and IL-27) showed a consistent rise in concentrations independently of the genetic variant of the virus. Although we believe our findings to be of scientific interest, we still consider them inconclusive; further investigation and comparison of immune responses to different variants of SARS-CoV-2 is required.

Immune Response Gaps Linked to SARS-CoV-2 Infection: Cellular Exhaustion, Senescence, or Both?

The COVID-19 pandemic, promoted by the SARS-CoV-2 respiratory virus, has resulted in widespread global morbidity and mortality. The immune response against this pathogen has shown a thin line between protective effects and pathological reactions resulting from the massive release of cytokines and poor viral clearance. The latter is possibly caused by exhaustion, senescence, or both of TCD8+ cells and reduced activity of natural killer (NK) cells. The imbalance between innate and adaptive responses during the early stages of infection caused by SARS-CoV-2 contributes to the ineffective control of viral spread. The present study evaluated the tissue immunoexpression of the tissue biomarkers (Arginase-1, CCR4, CD3, CD4, CD8, CD20, CD57, CD68, CD138, IL-4, INF-α, INF-γ, iNOS, PD-1, Perforin and Sphingosine-1) to understand the cellular immune response triggered in patients who died of COVID-19. We evaluated twenty-four paraffin-embedded lung tissue samples from patients who died of COVID-19 (COVID-19 group) and compared them with ten lung tissue samples from patients who died of H1N1pdm09 (H1N1 group) with the immunohistochemical markers mentioned above. In addition, polymorphisms in the Perforin gene were genotyped through Real-Time PCR. Significantly increased tissue immunoexpression of Arginase, CD4, CD68, CD138, Perforin, Sphingosine-1, and IL-4 markers were observed in the COVID-19 group. A significantly lower immunoexpression of CD8 and CD57 was also found in this group. It is suggested that patients who died from COVID-19 had a poor cellular response concerning viral clearance and adaptive response going through tissue repair.

Lung mitochondrial DNA copy number, inflammatory biomarkers, gene transcription and gene methylation in vapers and smokers

BACKGROUND

Mitochondrial DNA copy number (mtCN) maintains cellular function and homeostasis, and is linked to nuclear DNA methylation and gene expression. Increased mtCN in the blood is associated with smoking and respiratory disease, but has received little attention for target organ effects for smoking or electronic cigarette (EC) use.

METHODS

Bronchoscopy biospecimens from healthy EC users, smokers (SM), and never-smokers (NS) were assessed for associations of mtCN with mtDNA point mutations, immune responses, nuclear DNA methylation and gene expression using linear regression. Ingenuity pathway analysis was used for enriched pathways. GEO and TCGA respiratory disease datasets were used to explore the involvement of mtCN-associated signatures.

FINDINGS

mtCN was higher in SM than NS, but EC was not statistically different from either. Overall there was a negative association of mtCN with a point mutation in the D-loop but no difference within groups. Positive associations of mtCN with IL-2 and IL-4 were found in EC only. mtCN was significantly associated with 71,487 CpGs and 321 transcripts. 263 CpGs were correlated with nearby transcripts for genes enriched in the immune system. EC-specific mtCN-associated-CpGs and genes were differentially expressed in respiratory diseases compared to controls, including genes involved in cellular movement, inflammation, metabolism, and airway hyperresponsiveness.

INTERPRETATION

Smoking may elicit a lung toxic effect through mtCN. While the impact of EC is less clear, EC-specific associations of mtCN with nuclear biomarkers suggest exposure may not be harmless. Further research is needed to understand the role of smoking and EC-related mtCN on lung disease risks.

FUNDING

The National Cancer Institute, the National Heart, Lung, and Blood Institute, the Food and Drug Administration Center for Tobacco Products, the National Center For Advancing Translational Sciences, and Pelotonia Intramural Research Funds.

Lung Inflammasome Activation in SARS-CoV-2 Post-Mortem Biopsies

The inflammasome complex is a key part of chronic diseases and acute infections, being responsible for cytokine release and cell death mechanism regulation. The SARS-CoV-2 infection is characterized by a dysregulated cytokine release. In this context, the inflammasome complex analysis within SARS-CoV-2 infection may prove beneficial to understand the disease’s mechanisms. Post-mortem minimally invasive autopsies were performed in patients who died from COVID-19 (n = 24), and lung samples were compared to a patient control group (n = 11) and an Influenza A virus H1N1 subtype group from the 2009 pandemics (n = 10). Histological analysis was performed using hematoxylin-eosin staining. Immunohistochemical (IHC) staining was performed using monoclonal antibodies against targets: ACE2, TLR4, NF-κB, NLRP-3 (or NALP), IL-1β, IL-18, ASC, CASP1, CASP9, GSDMD, NOX4, TNF-α. Data obtained from digital analysis underwent appropriate statistical tests. IHC analysis showed biomarkers that indicate inflammasome activation (ACE2; NF-κB; NOX4; ASC) were significantly increased in the COVID-19 group (p < 0.05 for all) and biomarkers that indicate cell pyroptosis and inflammasome derived cytokines such as IL-18 (p < 0.005) and CASP1 were greatly increased (p < 0.0001) even when compared to the H1N1 group. We propose that the SARS-CoV-2 pathogenesis is connected to the inflammasome complex activation. Further studies are still warranted to elucidate the pathophysiology of the disease.

The effects of systemic immunomodulatory treatments on COVID-19 outcomes in patients with atopic dermatitis: Results from the global SECURE-AD registry

BACKGROUND

Limited data are available on the effects of systemic immunomodulatory treatments on COVID-19 outcomes in patients with atopic dermatitis (AD).

OBJECTIVE

To investigate COVID-19 outcomes in patients with AD treated with or without systemic immunomodulatory treatments, using a global registry platform.

METHODS

Clinicians were encouraged to report cases of COVID-19 in their patients with AD in the Surveillance Epidemiology of Coronavirus Under Research Exclusion for Atopic Dermatitis (SECURE-AD) registry. Data entered from 1 April 2020 to 31 October 2021 were analysed using multivariable logistic regression. The primary outcome was hospitalization from COVID-19, according to AD treatment groups.

RESULTS

442 AD patients (mean age 35.9 years, 51.8% male) from 27 countries with strongly suspected or confirmed COVID-19 were included in analyses. 428 (96.8%) patients were treated with a single systemic therapy (n = 297 [67.2%]) or topical therapy only (n = 131 [29.6%]). Most patients treated with systemic therapies received dupilumab (n = 216). Fourteen patients (3.2%) received a combination of systemic therapies. Twenty-six patients (5.9%) were hospitalized. No deaths were reported. Patients treated with topical treatments had significantly higher odds of hospitalization, compared with those treated with dupilumab monotherapy (odds ratio (OR) 4.65 [95%CI 1.71-14.78]), including after adjustment for confounding variables (adjusted OR (aOR) 4.99 [95%CI 1.4-20.84]). Combination systemic therapy which did not include systemic corticosteroids was associated with increased odds of hospitalization, compared with single agent non-steroidal immunosuppressive systemic treatment (OR 8.09 [95%CI 0.4-59.96], aOR 37.57 [95%CI 1.05-871.11]). Hospitalization was most likely in patients treated with combination systemic therapy which included systemic corticosteroids (OR 40.43 [95%CI 8.16-207.49], aOR 45.75 [95%CI 4.54-616.22]).

CONCLUSIONS

Overall, the risk of COVID-19 complications appears low in patients with AD, even when treated with systemic immunomodulatory agents. Dupilumab monotherapy was associated with lower hospitalization than other therapies. Combination systemic treatment, particularly combinations including systemic corticosteroids, was associated with the highest risk of severe COVID-19.

Frontline workers: Mediators of mucosal immunity in community acquired pneumonia and COVID-19

The current COVID-19 pandemic has highlighted a need to further understand lung mucosal immunity to reduce the burden of community acquired pneumonia, including that caused by the SARS-CoV-2 virus. Local mucosal immunity provides the first line of defence against respiratory pathogens, however very little is known about the mechanisms involved, with a majority of literature on respiratory infections based on the examination of peripheral blood. The mortality for severe community acquired pneumonia has been rising annually, even prior to the current pandemic, highlighting a significant need to increase knowledge, understanding and research in this field. In this review we profile key mediators of lung mucosal immunity, the dysfunction that occurs in the diseased lung microenvironment including the imbalance of inflammatory mediators and dysbiosis of the local microbiome. A greater understanding of lung tissue-based immunity may lead to improved diagnostic and prognostic procedures and novel treatment strategies aimed at reducing the disease burden of community acquired pneumonia, avoiding the systemic manifestations of infection and excess morbidity and mortality.

SARS-CoV-2 variant spike and accessory gene mutations alter pathogenesis

A hallmark of the COVID-19 pandemic has been the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants that both increased transmission and improved immune evasion. Each variant possesses mutations throughout its genome, but little is known about their effect on pathogenesis. Specifically, we are interested in the accessory genes of SARS-CoV-2, which have been shown to affect viral pathogenesis through interference with the host innate immune response. In this work, we identify accessory genes that are responsible for pathogenesis in vivo and investigate the effect of variant nonspike genes on replication and disease in mice. This work identifies accessory genes as key drivers of pathogenesis and highlights the effect of nonspike genes on replication and pathogenesis.

The ongoing COVID-19 pandemic is a major public health crisis. Despite the development and deployment of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pandemic persists. The continued spread of the virus is largely driven by the emergence of viral variants, which can evade the current vaccines through mutations in the spike protein. Although these differences in spike are important in terms of transmission and vaccine responses, these variants possess mutations in the other parts of their genome that may also affect pathogenesis. Of particular interest to us are the mutations present in the accessory genes, which have been shown to contribute to pathogenesis in the host through interference with innate immune signaling, among other effects on host machinery. To examine the effects of accessory protein mutations and other nonspike mutations on SARS-CoV-2 pathogenesis, we synthesized both viruses possessing deletions in the accessory genes as well as viruses where the WA-1 spike is replaced by each variant spike gene in a SARS-CoV-2/WA-1 infectious clone. We then characterized the in vitro and in vivo replication of these viruses and compared them to both WA-1 and the full variant viruses. Our work has revealed that the accessory proteins contribute to SARS-CoV-2 pathogenesis and the nonspike mutations in variants can contribute to replication of SARS-CoV-2 and pathogenesis in the host. This work suggests that while spike mutations may enhance receptor binding and entry into cells, mutations in accessory proteins may alter clinical disease presentation.

Comparing the Cytokine Storms of COVID-19 and Pandemic Influenza

Emerging respiratory viruses are major health threats due to their potential to cause massive outbreaks. Over the past 2 years, the coronavirus disease 2019 (COVID-19) pandemic has caused millions of cases of severe infection and deaths worldwide. Although natural and vaccine-induced protective immune mechanisms against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been increasingly identified, the factors that determine morbimortality are less clear. Comparing the immune signatures of COVID-19 and other severe respiratory infections such as the pandemic influenza might help dissipate current controversies about the origin of their severe manifestations. As such, identifying homologies in the immunopathology of both diseases could provide targets for immunotherapy directed to block shared pathogenic mechanisms. Meanwhile, finding unique characteristics that differentiate each infection could shed light on specific immune alterations exploitable for diagnostic and individualized therapeutics for each case. In this study, we summarize immunopathological aspects of COVID-19 and pandemic influenza from the perspective of cytokine storms as the driving force underlying morbidity. Thereby, we analyze similarities and differences in the cytokine profiles of both infections, aiming to bring forward those molecules more attractive for translational medicine and drug development.

Role of Genetic Polymorphism Present in Macrophage Activation Syndrome Pathway in Post Mortem Biopsies of Patients with COVID-19

COVID-19 is a viral disease associated with an intense inflammatory response. Macrophage Activation Syndrome (MAS), the complication present in secondary hemophagocytic lymphohistiocytosis (sHLH), shares many clinical aspects observed in COVID-19 patients, and investigating the cytolytic function of the responsible cells for the first line of the immune response is important. Formalin-fixed paraffin-embedded lung tissue samples obtained by post mortem necropsy were accessed for three groups (COVID-19, H1N1, and CONTROL). Polymorphisms in MAS cytolytic pathway (PRF1; STX11; STXBP2; UNC13D and GZMB) were selected and genotyping by TaqMan^® assays (Thermo Fisher Scientific, MA, USA) using Real-Time PCR (Applied Biosystems, MA USA). Moreover, immunohistochemistry staining was performed with a monoclonal antibody against perforin, CD8+ and CD57+ proteins. Histopathological analysis showed high perforin tissue expression in the COVID-19 group; CD8+ was high in the H1N1 group and CD57+ in the CONTROL group. An association could be observed in two genes related to the cytolytic pathway (PRF1 rs885822 G/A and STXBP2 rs2303115 G/A). Furthermore, PRF1 rs350947132 was associated with increased immune tissue expression for perforin in the COVID-19 group. The genotype approach could help identify patients that are more susceptible, and for this reason, our results showed that perforin and SNPs in the PRF1 gene can be involved in this critical pathway in the context of COVID-19.

Role of transforming growth factor-beta 1 and connective tissue growth factor levels in coronavirus disease-2019-related lung Injury: a prospective, observational, cohort study

Background:

Coronavirus disease-2019 (COVID-19) results in acute lung injury. This study examined the usefulness of serum transforming growth factor-beta 1 (TGF-β1) and connective tissue growth factor (CTGF) levels in predicting disease severity in COVID-19 patients with pulmonary involvement.

Methods:

Fifty patients with confirmed COVID-19 and pulmonary involvement between September 2020, and February 2021 (Group 1) and 45 healthy controls (Group 2) were classified into three subgroups based on clinical severity: moderate, severe, and critical pneumonia. Serum TGF-β1 and CTGF concentrations were measured on days 1 and 7 of admission in Group 1 using an enzyme-linked immunosorbent assay. These concentrations were also measured in control cases. The mean serum TGF-β1 and CTGF levels were then compared among COVID-19 patients, based on clinical severity.

Results:

Significantly higher mean serum TGF-β1 and CTGF levels were observed on both days in Group 1 than in the control group. The mean serum TGF-β1 and CTGF levels on day 7 were also significantly higher than those on day 1 in Group 1. The critical patient group had the highest serum TGF-β1 and CTGF levels on both days, and the difference between this group and the moderate and severe pneumonia groups was significant. Cutoff values of 5.36 ng/mL for TGF-β1 and 626.2 pg/mL for CTGF emerged as predictors of COVID-19 with pulmonary involvement in receiver-operating characteristic curve analysis.

Conclusions:

TGF-β1 and CTGF are potential markers that can distinguish COVID-19 patients with pulmonary involvement and indicate disease severity. These findings may be useful for initiating treatment for early-stage COVID-19.

Immunomodulatory Effects of Lepidium meyenii Walp. Polysaccharides on an Immunosuppression Model Induced by Cyclophosphamide

Background

Lepidium meyenii Walp. (Maca) has emerged as a functional plant food and traditional herb owing to its biological activities; Maca polysaccharides as an important active component of Maca have good immunomodulatory effect; however, studies on the immunomodulatory effect of Maca polysaccharides are mainly focused on macrophages; little attention has been devoted to the mechanisms and other immune cells. This study is aimed at investigating the immunomodulatory effects and mechanisms of Maca polysaccharides.

Methods

Sixty mice were divided into five groups, and the mice were injected with cyclophosphamide to establish an immunosuppression model except for those in the common group. The body weights were measured, as well as immune-related indices, such as organ indices, haematological parameters, lymphocyte cycle, and proliferation, cytokine, and protein expression levels.

Results

The weight loss and immune organ index decline caused by cyclophosphamide could be reversed by MP. Furthermore, MP increased WBC and HGB counts and reduced the ratio of G0/G1 phase obviously, increased the proportion of S phase and G2/M phase in peripheral blood lymphocytes, increased the counts of CD4+ T cells and the ratio of CD4+/CD8+, and reduced the inhibition rate of splenic lymphocytes. MP affected the production of cytokines by increasing IFN-γ, TNF-α, and IL-2 levels and by decreasing IL-4 levels. MP increased the mRNA expression of T-bet and the protein expression of Bcl-2 in the spleen and decreased the protein expression of caspase-3 and Bax.

Conclusions

Maca polysaccharides might be the basic material for Maca's immunomodulatory effect. The mechanism was perhaps related to inhibiting lymphocyte apoptosis and promoting the balance of Th1/Th2 cell subsets.

Obesity-Mediated Immune Modulation: One Step Forward, (Th)2 Steps Back

Over the past decades, the relationship between the immune system and metabolism has become a major research focus. In this arena of immunometabolism the capacity of adipose tissue to secrete immunomodulatory molecules, including adipokines, within the underlying low-grade inflammation during obesity brought attention to the impact obesity has on the immune system. Adipokines, such as leptin and adiponectin, influence T cell differentiation into different T helper subsets and their activation during immune responses. Furthermore, within the cellular milieu of adipose tissue nutrient availability regulates differentiation and activation of T cells and changes in cellular metabolic pathways. Upon activation, T cells shift from oxidative phosphorylation to oxidative glycolysis, while the differential signaling of the kinase mammalian target of rapamycin (mTOR) and the nuclear receptor PPARγ, amongst others, drive the subsequent T cell differentiation. While the mechanisms leading to a shift from the typical type 2-dominated milieu in lean people to a Th1-biased pro-inflammatory environment during obesity are the subject of extensive research, insights on its impact on peripheral Th2-dominated immune responses become more evident. In this review, we will summarize recent findings of how Th2 cells are metabolically regulated during obesity and malnutrition, and how these states affect local and systemic Th2-biased immune responses.

Gene Networks of Hyperglycemia, Diabetic Complications, and Human Proteins Targeted by SARS-CoV-2: What Is the Molecular Basis for Comorbidity?

People with diabetes are more likely to have severe COVID-19 compared to the general population. Moreover, diabetes and COVID-19 demonstrate a certain parallelism in the mechanisms and organ damage. In this work, we applied bioinformatics analysis of associative molecular networks to identify key molecules and pathophysiological processes that determine SARS-CoV-2-induced disorders in patients with diabetes. Using text-mining-based approaches and ANDSystem as a bioinformatics tool, we reconstructed and matched networks related to hyperglycemia, diabetic complications, insulin resistance, and beta cell dysfunction with networks of SARS-CoV-2-targeted proteins. The latter included SARS-CoV-2 entry receptors (ACE2 and DPP4), SARS-CoV-2 entry associated proteases (TMPRSS2, CTSB, and CTSL), and 332 human intracellular proteins interacting with SARS-CoV-2. A number of genes/proteins targeted by SARS-CoV-2 (ACE2, BRD2, COMT, CTSB, CTSL, DNMT1, DPP4, ERP44, F2RL1, GDF15, GPX1, HDAC2, HMOX1, HYOU1, IDE, LOX, NUTF2, PCNT, PLAT, RAB10, RHOA, SCARB1, and SELENOS) were found in the networks of vascular diabetic complications and insulin resistance. According to the Gene Ontology enrichment analysis, the defined molecules are involved in the response to hypoxia, reactive oxygen species metabolism, immune and inflammatory response, regulation of angiogenesis, platelet degranulation, and other processes. The results expand the understanding of the molecular basis of diabetes and COVID-19 comorbidity.

The Robustness of Cellular Immunity Determines the Fate of SARS-CoV-2 Infection

Two years after the appearance of the SARS-CoV-2 virus, the causal agent of the current global pandemic, it is time to analyze the evolution of the immune protection that infection and vaccination provide. Cellular immunity plays an important role in limiting disease severity and the resolution of infection. The early appearance, breadth and magnitude of SARS-CoV-2 specific T cell response has been correlated with disease severity and it has been thought that T cell responses may be sufficient to clear infection with minimal disease in COVID-19 patients with X-linked or autosomal recessive agammaglobulinemia. However, our knowledge of the phenotypic and functional diversity of CD8+ cytotoxic lymphocytes, CD4+ T helper cells, mucosal-associated invariant T (MAIT) cells and CD4+ T follicular helper (Tfh), which play a critical role in infection control as well as long-term protection, is still evolving. It has been described how CD8+ cytotoxic lymphocytes interrupt viral replication by secreting antiviral cytokines (IFN-γ and TNF-α) and directly killing infected cells, negatively correlating with stages of disease progression. In addition, CD4+ T helper cells have been reported to be key pieces, leading, coordinating and ultimately regulating antiviral immunity. For instance, in some more severe COVID-19 cases a dysregulated CD4+ T cell signature may contribute to the greater production of pro-inflammatory cytokines responsible for pathogenic inflammation. Here we discuss how cellular immunity is the axis around which the rest of the immune system components revolve, since it orchestrates and leads antiviral response by regulating the inflammatory cascade and, as a consequence, the innate immune system, as well as promoting a correct humoral response through CD4+ Tfh cells. This review also analyses the critical role of cellular immunity in modulating the development of high-affinity neutralizing antibodies and germinal center B cell differentiation in memory and long-lived antibody secreting cells. Finally, since there is currently a high percentage of vaccinated population and, in some cases, vaccine booster doses are even being administered in certain countries, we have also summarized newer approaches to long-lasting protective immunity and the cross-protection of cellular immune response against SARS-CoV-2.

Molecular and cellular immune features of aged patients with severe COVID-19 pneumonia

Aging is a major risk factor for developing severe COVID-19, but few detailed data are available concerning immunological changes after infection in aged individuals. Here we describe main immune characteristics in 31 patients with severe SARS-CoV-2 infection who were >70 years old, compared to 33 subjects <60 years of age. Differences in plasma levels of 62 cytokines, landscape of peripheral blood mononuclear cells, T cell repertoire, transcriptome of central memory CD4⁺ T cells, specific antibodies are reported along with features of lung macrophages. Elderly subjects have higher levels of pro-inflammatory cytokines, more circulating plasmablasts, reduced plasmatic level of anti-S and anti-RBD IgG3 antibodies, lower proportions of central memory CD4⁺ T cells, more immature monocytes and CD56⁺ pro-inflammatory monocytes, lower percentages of circulating follicular helper T cells (cTfh), antigen-specific cTfh cells with a less activated transcriptomic profile, lung resident activated macrophages that promote collagen deposition and fibrosis. Our study underlines the importance of inflammation in the response to SARS-CoV-2 and suggests that inflammaging, coupled with the inability to mount a proper anti-viral response, could exacerbate disease severity and the worst clinical outcome in old patients.

Patients over the age of 70 show inflammaging and a weaker anti-viral response to SARS-CoV-2, pointing at the immunological changes associated with COVID-19 severity and outcome for aged patients.

Pneumomediastinum After COVID-19

A preadolescent female presented to the emergency department with an acute asthma exacerbation. Chest radiograph and computed tomography scan showed extensive pneumomediastinum with a small pneumopericardium without a distinct source for this air leak. The patient was admitted for noninvasive monitoring, analgesia, and high concentration oxygen. Serial chest radiographs showed marked improvement following high concentration oxygen, and she was discharged on hospital day 3. Spontaneous pneumomediastinum and pneumopericardium are rare complications of asthma that can often be managed conservatively but should be considered on the differential for this patient population, and may be a complication of COVID-19.

SARS-CoV-2 Variant Spike and accessory gene mutations alter pathogenesis.. [PMID: 35677080 PMCID: PMC9176647 DOI: 10.1101/2022.05.31.494211]

The ongoing COVID-19 pandemic is a major public health crisis. Despite the development and deployment of vaccines against SARS-CoV-2, the pandemic persists. The continued spread of the virus is largely driven by the emergence of viral variants, which can evade the current vaccines through mutations in the Spike protein. Although these differences in Spike are important in terms of transmission and vaccine responses, these variants possess mutations in the other parts of their genome which may affect pathogenesis. Of particular interest to us are the mutations present in the accessory genes, which have been shown to contribute to pathogenesis in the host through innate immune signaling, among other effects on host machinery. To examine the effects of accessory protein mutations and other non-spike mutations on SARS-CoV-2 pathogenesis, we synthesized viruses where the WA1 Spike is replaced by each variant spike genes in a SARS-CoV-2/WA-1 infectious clone. We then characterized the in vitro and in vivo replication of these viruses and compared them to the full variant viruses. Our work has revealed that non-spike mutations in variants can contribute to replication of SARS-CoV-2 and pathogenesis in the host and can lead to attenuating phenotypes in circulating variants of concern. This work suggests that while Spike mutations may enhance receptor binding and entry into cells, mutations in accessory proteins may lead to less clinical disease, extended time toward knowing an infection exists in a person and thus increased time for transmission to occur.

Possible Role of Matrix Metalloproteinases and TGF-β in COVID-19 Severity and Sequelae

The costs of coronavirus disease 2019 (COVID-19) are devastating. With millions of deaths worldwide, specific serological biomarkers, antiviral agents, and novel therapies are urgently required to reduce the disease burden. For these purposes, a profound understanding of the pathobiology of COVID-19 is mandatory. Notably, the study of immunity against other respiratory infections has generated reference knowledge to comprehend the paradox of the COVID-19 pathogenesis. Past studies point to a complex interplay between cytokines and other factors mediating wound healing and extracellular matrix (ECM) remodeling that results in exacerbated inflammation, tissue injury, severe manifestations, and a sequela of respiratory infections. This review provides an overview of the immunological process elicited after severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. Also, we analyzed available data about the participation of matrix metalloproteinases (MMPs) and transforming growth factor-beta (TGF-β) in immune responses of the lungs. Furthermore, we discuss their possible implications in severe COVID-19 and sequela, including pulmonary fibrosis, and remark on the potential of these molecules as biomarkers for diagnosis, prognosis, and treatment of convalescent COVID-19 patients. Our review provides a theoretical framework for future research aimed to discover molecular hallmarks that, combined with clinical features, could serve as therapeutic targets and reliable biomarkers of the different clinical forms of COVID-19, including convalescence.

Mapping the epithelial-immune cell interactome upon infection in the gut and the upper airways

Increasing evidence points towards the key role of the epithelium in the systemic and over-activated immune response to viral infection, including SARS-CoV-2 infection. Yet, how viral infection alters epithelial-immune cell interactions regulating inflammatory responses, is not well known. Available experimental approaches are insufficient to properly analyse this complex system, and computational predictions and targeted data integration are needed as an alternative approach. In this work, we propose an integrated computational biology framework that models how infection alters intracellular signalling of epithelial cells and how this change impacts the systemic immune response through modified interactions between epithelial cells and local immune cell populations. As a proof-of-concept, we focused on the role of intestinal and upper-airway epithelial infection. To characterise the modified epithelial-immune interactome, we integrated intra- and intercellular networks with single-cell RNA-seq data from SARS-CoV-2 infected human ileal and colonic organoids as well as from infected airway ciliated epithelial cells. This integrated methodology has proven useful to point out specific epithelial-immune interactions driving inflammation during disease response, and propose relevant molecular targets to guide focused experimental analysis.