Neutrophil extracellular traps (NETs) play a pivotal role in immunity and autoinflammatory disease, leading us to hypothesize that NETs are crucial in Guillain-Barre Syndrome (GBS) after SARS-CoV-2 infection.

By collecting six Gene Expression Omnibus (GEO) datasets from the GEO database and dividing them into discovery and validation sets, we screened differentially expressed genes (DEGs) within the discovery set, with further analyses using functional enrichment analysis. Using single-sample gene set enrichment analysis (ssGSEA), we assessed immune cell infiltration in both coronavirus disease 2019 (COVID-19) and GBS datasets. NETs-related genes (NETRGs) were identified through a protein-protein interaction (PPI) network and NETs gene datasets. Finally, candidate drugs were screened using Connectivity Map.

In this study, a total of 3254 DEGs were identified from the COVID-19 dataset, and 692 DEGs were obtained from the GBS dataset. Among these, 145 co-expressed DEGs were obtained. Bioinformatics functional analysis indicated that co-expressed DEGs were predominantly gathered in immune-related and inflammatory response pathways. Employing various algorithms, we identified MMP9, CAMP, and CASP1 as NETRGs, demonstrating good discriminatory capacity in COVID-19 and GBS. Notably, neutrophils and macrophages were identified as co-upregulated differential immune infiltrating cells significantly associated with both COVID-19 and GBS. Moreover, we identified 10 candidate drugs for patients with post-COVID-19 GBS.

In conclusion, MMP9, CASP1, and CAMP were identified as promising biomarkers and potential targets for therapy of post-COVID-19 GBS.

Despite vaccines, rapidly mutating viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continue to threaten human health due to an impaired immunoregulatory pathway and a hyperactive immune response. Our understanding of the local immune mechanisms used by tissue-resident macrophages to safeguard the host from excessive inflammation during SARS-CoV-2 infection remains limited. Here, we found that nerve- and airway-associated interstitial macrophages (NAMs) are required to control mouse-adapted SARS-CoV-2 (MA-10) infection. Control mice restricted lung viral distribution and survived infection, whereas NAM depletion enhanced viral spread and inflammation and led to 100% mortality. Mechanistically, type I interferon receptor (IFNAR) signaling by NAMs was critical for limiting inflammation and viral spread, and IFNAR deficiency in CD169+ macrophages mirrored NAM-depleted outcomes and abrogated their expansion. These findings highlight the essential protective role of NAMs in regulating viral spread and inflammation, offering insights into SARS-CoV-2 pathogenesis and underscoring the importance of NAMs in mediating host immunity and disease tolerance.

Severe coronavirus outbreaks, including SARS, MERS, and COVID-19, have underscored the urgent need for effective antiviral therapies. This study evaluated the antiviral activity of biflavanones isolated from Ouratea spectabilis-specifically ouratein (Our-) A, B, C, and D-against murine hepatitis virus (MHV-3) and human SARS-CoV-2. Cells infected with MHV-3 or SARS-CoV-2 were treated with ourateins, and viral replication was assessed using plaque assays. Mice infected with MHV-3 were treated with Our-D either orally or intraperitoneally. Key assessments included leukocyte counts, cytokine and chemokine levels, histological analysis, and survival rates. The mechanism of action was explored through in silico and in vitro studies focused on the binding and inhibition of the main protease (Mpro). Our-D significantly inhibited the replication of both viruses, with a selective index of 2.5 for MHV-3 and 14.9 for SARS-CoV-2. In vivo, Our-D reduced leukocyte infiltration in the lungs, decreased CCL2 levels, increased IL-10, and lowered plasma IL-6 and CXCL1 levels. Additionally, Our-D mitigated lung damage, partially restored betacoronavirus-induced lymphopenia, and reduced viral loads in the lungs, heart, and spleen, ultimately improving survival in mice. In silico studies revealed that Our-A and Our-C had strong binding affinity for Mpro, and both significantly inhibited Mpro activity in vitro, unlike Our-D. Our-D protected mice from coronavirus infection by modulating the inflammatory response and reducing viral loads, with minimal effect on Mpro inhibition, suggesting alternative mechanisms for its antiviral activity.

This study evaluated the predictive value of Krebs von den Lungen-6 (KL-6) for the development of coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) and its association with mortality in critically ill COVID-19 patients. A retrospective single-center cohort study was conducted on critically ill COVID-19 patients who required high-flow oxygen or mechanical ventilation between January 2021 and June 2023. Serial serum KL-6 levels were measured at admission and weekly thereafter. The predictive performance of initial KL-6 was assessed using ROC curve analysis, and risk factors for CAPA and 30-day mortality were analyzed using multivariable models. Among 238 patients, 25 (10.5%) developed CAPA. Initial KL-6 demonstrated good discriminative ability for CAPA prediction (AUC 0.745; 95% CI: 0.685-0.799), with an optimal cutoff of 270.9 U/ml (sensitivity: 88.0%, specificity: 55.4%). KL-6 ≥ 270.9 U/ml remained independently associated with CAPA (aHR: 9.66; 95% CI: 2.28-40.89) after multivariable analysis. Serial measurements showed a trend toward a greater increase in KL-6 levels among CAPA patients than non-CAPA patients (median difference: 259.9 vs. 73.0 U/ml, P = .053). Additional independent predictors of CAPA included inotropic/vasopressor support, diabetes mellitus, and tocilizumab use. CAPA patients had higher all-cause 30-day mortality (60.8% vs. 45.2%; P = .020), which remained significant after adjustment (aHR: 2.19; 95% CI: 1.08-4.15). Furthermore, KL-6 was independently associated with 30-day mortality (aHR: 1.03 per 100 U/ml; 95% CI: 1.00-1.07). These findings suggest that KL-6 is a promising biomarker for predicting CAPA and mortality in critically ill COVID-19 patients.

Prognostic biomarkers have been widely studied in COVID-19, but their levels may be influenced by treatment strategies. This study examined plasma biomarkers and proteomic survival prediction in two unvaccinated hospitalized COVID-19 cohorts receiving different treatments. In a derivation cohort (n = 126) from early 2020, we performed plasma proteomic profiling and evaluated innate and complement system immune markers. A proteomic model based on differentially expressed proteins predicted 30-day mortality with an area under the curve (AUC) of 0.81. The model was tested in a validation cohort (n = 80) from late 2020, where patients received remdesivir and dexamethasone, and performed with an AUC of 0.75. Biomarker levels varied considerably between cohorts, sometimes in opposite directions, highlighting the impact of treatment regimens on biomarker expression. These findings underscore the need to account for treatment effects when developing prognostic models, as treatment differences may limit their generalizability across populations.

ObjectiveTo evaluate the efficacy and adverse events of immunomodulators in the treatment of severe coronavirus disease 2019 (COVID-19).MethodsA literature search for the meta-analysis was performed using PubMed, The Cochrane Library, Embase, Wanfang Data, CNKI, and Web of Science to identify randomized controlled trials assessing the outcomes of patients treated with corticosteroids alone and/or interleukin-6 receptor antagonists for COVID-19. The risk of bias was assessed using the Cochrane method. The protocol was registered with PROSPERO (registry number: CRD42022356904).ResultsCompared with patients receiving standard of care, patients treated with corticosteroids alone had an increased risk of 14-day in-hospital death, whereas those treated with interleukin-6 receptor antagonists alone or in combination with corticosteroids had a lower risk of 14-day in-hospital death. Corticosteroid therapy alone was associated with increased risk of several adverse events, including intensive care unit admission and non-invasive ventilation, whereas interleukin-6 receptor antagonists alone or in combination with corticosteroids were not linked to adverse effects.ConclusionsThe findings supported the safety and efficacy of interleukin-6 receptor antagonists, either alone or together with corticosteroids, in patients with severe COVID-19; evidence supporting the efficacy and safety of corticosteroids monotherapy is lacking.

We investigated the long-term kidney and cardiovascular outcomes of patients with chronic kidney disease (CKD) after COVID-19. Our retrospective cohort consisted of 834 CKD patients with COVID-19 and 6,167 CKD patients without COVID-19 between 3/11/2020 to 7/1/2023. Multivariate competing risk regression models were used to estimate risk (as adjusted hazard ratios (aHR) with 95% confidence intervals (CI)) of CKD progression to a more advanced stage (Stage 4 or 5) and major adverse kidney events (MAKE), and risk of major adverse cardiovascular events (MACE) at 6-, 12-, and 24-month follow up. Hospitalized COVID-19 patients at 12 and 24 months (aHR 1.62 95% CI[1.24,2.13] and 1.76 [1.30, 2.40], respectively), but not non-hospitalized COVID-19 patients, were at higher risk of CKD progression compared to those without COVID-19. Both hospitalized and non-hospitalized COVID-19 patients were at higher risk of MAKE at 6-, 12- and 24-months compared to those without COVID-19. Hospitalized COVID-19 patients at 6-, 12- and 24-months (aHR 1.73 [1.21, 2.50], 1.77 [1.34, 2.33], and 1.31 [1.05, 1.64], respectively), but not non-hospitalized COVID-19 patients, were at higher risk of MACE compared to those without COVID-19. COVID-19 increases the risk of long-term CKD progression and cardiovascular events in patients with CKD. These findings highlight the need for close follow up care and therapies that slow CKD progression in this high-risk subgroup.

The emergence of the COVID-19 pandemic made it critical to understand the immune and inflammatory responses to the SARS-CoV-2 virus. It became increasingly recognized that the immune response was a key mediator of illness severity and that its mechanisms needed to be better understood. Early infection of both tissue and immune cells, such as macrophages, leading to pyroptosis-mediated inflammasome production in an organ system critical for systemic oxygenation likely plays a central role in the morbidity wrought by SARS-CoV-2. Delayed transcription of Type I and Type III interferons by SARS-CoV-2 may lead to early disinhibition of viral replication. Cytokines such as interleukin-1 (IL-1), IL-6, IL-12, and tumor necrosis factor α (TNFα), some of which may be produced through mechanisms involving nuclear factor kappa B (NF-κB), likely contribute to the hyperinflammatory state in patients with severe COVID-19. Lymphopenia, more apparent among natural killer (NK) cells, CD8+ T-cells, and B-cells, can contribute to disease severity and may reflect direct cytopathic effects of SARS-CoV-2 or end-organ sequestration. Direct infection and immune activation of endothelial cells by SARS-CoV-2 may be a critical mechanism through which end-organ systems are impacted. In this context, endovascular neutrophil extracellular trap (NET) formation and microthrombi development can be seen in the lungs and other critical organs throughout the body, such as the heart, gut, and brain. The kidney may be among the most impacted extrapulmonary organ by SARS-CoV-2 infection owing to a high concentration of ACE2 and exposure to systemic SARS-CoV-2. In the kidney, acute tubular injury, early myofibroblast activation, and collapsing glomerulopathy in select populations likely account for COVID-19-related AKI and CKD development. The development of COVID-19-associated nephropathy (COVAN), in particular, may be mediated through IL-6 and signal transducer and activator of transcription 3 (STAT3) signaling, suggesting a direct connection between the COVID-19-related immune response and the development of chronic disease. Chronic manifestations of COVID-19 also include systemic conditions like Multisystem Inflammatory Syndrome in Children (MIS-C) and Adults (MIS-A) and post-acute sequelae of COVID-19 (PASC), which may reflect a spectrum of clinical presentations of persistent immune dysregulation. The lessons learned and those undergoing continued study likely have broad implications for understanding viral infections' immunologic and inflammatory consequences beyond coronaviruses.

A hyperinflammatory state with highly elevated concentrations of inflammatory biomarkers such as C-reactive protein (CRP) is a characteristic feature of severe coronavirus disease 2019 (COVID-19). To examine a potential role of common genetic factors that may influence COVID-19 outcomes, we investigated whether individuals with a polygenic predisposition for a pro-inflammatory response (in the form of Polygenic Scores) are more likely to develop severe COVID-19. The innovative approach of polygenic scores to investigate genetic factors in COVID-19 severity should provide a comprehensive approach beyond single-gene studies. In our cohort of 156 patients of European ancestry, two overlapping Polygenic Scores (PGS) predicting a genetic predisposition to basal CRP concentrations were significantly different between non-severe and severe COVID-19 cases and were associated with less severe COVID-19 outcomes. Furthermore, specific single nucleotide polymorphisms (SNPs) that contribute to either of the two Polygenic Scores predicting basal CRP levels are associated with different traits that represent risk factors for COVID-19 disease initiation (ACE2 receptor, viral replication) and progression (CRP). We suggest that genetically determined enforced CRP formation may contribute to strengthening of innate immune responses and better initial pathogen control thereby reducing the risk of subsequent hyperinflammation and adverse course of COVID-19.

Disease tolerance is an evolutionarily conserved host defense strategy that preserves tissue integrity and physiology without affecting pathogen load. Unlike host resistance, the mechanisms underlying disease tolerance remain poorly understood. In the present study, we investigated whether an adjuvant (β-glucan) can reprogram innate immunity to provide protection against influenza A virus (IAV) infection. β-Glucan treatment reduces the morbidity and mortality against IAV infection, independent of host resistance. The enhanced survival is the result of increased recruitment of neutrophils via RoRγt+ T cells in the lung tissue. β-Glucan treatment promotes granulopoiesis in a type 1 interferon-dependent manner that leads to the generation of a unique subset of immature neutrophils utilizing a mitochondrial oxidative metabolism and producing interleukin-10. Collectively, our data indicate that β-glucan reprograms hematopoietic stem cells to generate neutrophils with a new 'regulatory' function, which is required for promoting disease tolerance and maintaining lung tissue integrity against viral infection.

This paper explores conflicting perspectives on the adaptive significance of phenotypic plasticity during fetal and early postnatal development and the impact that stressors experienced during this critical early-life period have on later-life morbidity and mortality risk.

The sample (n = 216) comprised archeologically-recovered human skeletons. A geometric morphometric (GM) method was employed to evaluate first permanent molar (M1) fluctuating asymmetry (FA) and provide a proxy for early-life stress. Shifts in later-life physiology were inferred through two inflammatory lesions: periosteal new bone formation (PNBF) and periodontal disease (PD). To explore mortality risk, age-at-death was estimated through dental development for skeletally immature individuals (n = 104) and through senescent skeletal changes for mature skeletons (n = 112).

Significant differences were found in M1 FA between groups, with the immature cohort associated with elevated FA. Within-group analysis revealed age-at-death in the immature group had a significant positive relationship with M1 FA and PD presence. In the mature group, alongside sex and the co-occurrence of PD and PNBF, FA was a significant predictor of a shorter life. Higher FA was also associated with active and bilaterally expressed PNBF.

It is theorized that early-life stress, if survived, programmed a hyperinflammatory response to environmentally-mediated physiological perturbations which increased the chances of survival during subsequent development but also elevated later-life mortality risk. Findings demonstrate a complicated relationship between developmental stress and physiological shifts that helps to illustrate the adaptive significance of early-life programming and support the Thrifty Phenotype hypothesis.

The 2019 coronavirus illness (COVID 2019) first manifests as a newly identified pneumonia and may quickly escalate to acute respiratory distress syndrome, which has caused a global pandemic. Except for individualized supportive care, no curative therapy has been steadfastly advised for COVID-19 up until this point. T cells and virus-specific T lymphocytes are required to guard against viral infection, particularly COVID-19. Delayed immunological reconstitution (IR) and cytokine storm (CS) continue to be significant barriers to COVID-19 cure. While severe COVID-19 patients who survived the disease had considerable lymphopenia and increased neutrophils, especially in the elderly, their T cell numbers gradually recovered. Exhausted T lymphocytes and elevated levels of pro-inflammatory cytokines, including IL6, IL10, IL2, and IL17, are observed in peripheral blood and the lungs. It implies that while convalescent plasma, IL-6 blocking, mesenchymal stem cells, and corticosteroids might decrease CS, Thymosin α1 and adaptive COVID-19-specific T cells could enhance IR. There is an urgent need for more clinical research in this area throughout the world to open the door to COVID-19 treatment in the future.

Cytokine release triggered by a hyperactive immune response is thought to contribute to severe acute respiratory syndrome coronavirus 2019 (SARS-CoV-2)-related respiratory failure. Bruton tyrosine kinase (BTK) is involved in innate immunity, and BTK inhibitors block cytokine release. We assessed the next-generation BTK inhibitor zanubrutinib in SARS-CoV-2-infected patients with respiratory distress.

Cohort 1 had a prospective, randomized, double-blind, placebo-controlled design; cohort 2 had a single-arm design. Adults with SARS-CoV-2 requiring hospitalization (without mechanical ventilation) were randomized in cohort 1. Those on mechanical ventilation ≤24 hours were enrolled in cohort 2. Patients were randomized 1:1 to zanubrutinib 320 mg once daily or placebo (cohort 1), or received zanubrutinib 320 mg once daily (cohort 2). Co-primary endpoints were respiratory failure-free survival rate and time to return to breathing room air at 28 days. Corollary studies to assess zanubrutinib's impact on immune response were performed.

Sixty-three patients in cohort 1 received zanubrutinib (n=30) or placebo (n=33), with median treatment duration of 8.5 and 7.0 days, respectively. The median treatment duration in cohort 2 (n=4) was 13 days; all discontinued treatment early. In cohort 1, respiratory failure-free survival and the estimated rates of not returning to breathing room air by day 28 were not significantly different between treatments. Importantly, serological response to coronavirus disease 2019 (COVID-19) was not impacted by zanubrutinib. Lower levels of granulocyte colony-stimulating factor, interleukin (IL)-10, monocyte chemoattractant protein-1, IL-4, and IL-13 were observed in zanubrutinib-treated patients. Moreover, single-cell transcriptome analysis showed significant downregulation of inflammatory mediators (IL-6, IL-8, macrophage colony-stimulating factor, macrophage inflammatory protein-1α, IL-1β) and signaling pathways (JAK1, STAT3, TYK2), and activation of gamma-delta T cells in zanubrutinib-treated patients.

Marked reduction in inflammatory signaling with preserved SARS-CoV-2 serological response was observed in hospitalized patients with COVID-19 respiratory distress receiving zanubrutinib. Despite these immunological findings, zanubrutinib did not show improvement over placebo in clinical recovery from respiratory distress. Concurrent administration of steroids and antiviral therapy to most patients may have contributed to these results. Investigation of zanubrutinib may be warranted in other settings where cytokine release and immune cell exhaustion are important.

https://www.clinicaltrials.gov/study/NCT04382586, identifier NCT04382586.

The mucosal immune system, as the most extensive peripheral immune network, serves as the frontline defense against a myriad of microbial and dietary antigens. It is crucial in preventing pathogen invasion and establishing immune tolerance. A comprehensive understanding of mucosal immunity is essential for developing treatments that can effectively target diseases at their entry points, thereby minimizing the overall impact on the body. Despite its importance, our knowledge of mucosal immunity remains incomplete, necessitating further research. The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has underscored the critical role of mucosal immunity in disease prevention and treatment. This systematic review focuses on the dynamic interactions between mucosa-associated lymphoid structures and related diseases. We delve into the basic structures and functions of these lymphoid tissues during disease processes and explore the intricate regulatory networks and mechanisms involved. Additionally, we summarize novel therapies and clinical research advances in the prevention of mucosal immunity-related diseases. The review also addresses the challenges in developing mucosal vaccines, which aim to induce specific immune responses while maintaining tolerance to non-pathogenic microbes. Innovative therapies, such as nanoparticle vaccines and inhalable antibodies, show promise in enhancing mucosal immunity and offer potential for improved disease prevention and treatment.

Modified Dachaihu decoction (MDD) is a herbal prescription that has shown promising therapeutic benefits in ameliorating pulmonary diseases in clinical practice. However, the detailed mechanisms remain unclear.

This study aimed to elucidate the lung-protective effects of MDD against acute lung injury (ALI) and the involvement of underlying mechanisms.

High-performance liquid chromatography (HPLC) was performed to identify the main active ingredients of MDD. Network pharmacological method was adapted to explore the potential mechanisms. Mice were orally administered MDD (11.25, 22.5, and 45 g/kg) once daily for 7 days. H&E staining was performed to evaluate histological changes in the lungs. Levels of inflammatory cytokines and oxidative stress markers were measured to determine the extent of lung injury. Total protein content in bronchoalveolar lavage fluid (BALF) and lung wet/dry weight ratio were measured to assess the severity of pulmonary edema. TUNEL staining and immunohistochemistry analysis were performed to detect apoptosis. RT-qPCR and western blotting were performed to validate the mechanisms involved.

About 10 main active ingredients of MDD were identified. Notably, treatment with MDD resulted in a remarkable reduction in total protein content in BALF and lung W/D weight ratio, as well as substantial mitigation of the inflammatory response and oxidative stress. Mechanistically, the PI3K/Akt signalling pathway was activated. Moreover, MDD pretreatment downregulated p53 and caspase-9 mRNA expression and decreased the Bax/Bcl-2 ratio to ameliorate lung apoptosis.

MDD exhibited pronounced therapeutic effects via attenuating inflammatory response, oxidative stress, and apoptosis. These therapeutic effects could be attributed to the synergistic effect of the main active ingredients and are believed to be associated with the activation of the PI3K/Akt pathway.

In this study, we examined preexisting systemic inflammation before COVID-19 (SIC), as assessed through C-reactive protein (CRP) levels, to gain insights into the origins of acute kidney injury (AKI) in adults with comorbidities affected by COVID-19. Although aging is not categorized as a disease, it is characterized by chronic inflammation, and older individuals typically exhibit higher circulating levels of inflammatory molecules, particularly CRP, compared to younger individuals. Conversely, elevated CRP concentrations in older adults have been linked with the development of comorbidities. Simultaneously, these comorbidities contribute to the production of inflammatory molecules, including CRP. Consequently, older adults with comorbidities have higher CRP concentrations than their counterparts without comorbidities or those with fewer comorbidities. Given that CRP levels are correlated with the development and severity of AKI in non-COVID-19 patients, we hypothesized that individuals with greater SIC are more likely to develop AKI during SARS-CoV-2 infection than those with less SIC.

Receptor-interacting protein kinase 1 (RIPK1), a serine/threonine protein kinase, is mainly activated by pro-inflammatory cytokines and pathogens, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and its activation could result in apoptosis, necroptosis, or inflammation. This study was conducted to evaluate the safety and efficacy of a potent and selective inhibitor of RIPK1, SIR1-365, in hospitalized patients with severe coronavirus disease 2019 (COVID-19).

This multicenter, randomized, double-blind, phase 1b study screened patients from December 18, 2020 until November 27, 2021. Adults hospitalized with severe COVID-19 (diagnosed ≤2 weeks before screening) were randomized 1:1 to receive oral placebo or SIR1-365 100 mg three times daily for ≤14 consecutive days, with standard-of-care. The primary objective was to evaluate SIR1-365 safety and tolerability. Secondary objectives included an assessment of SIR1-365 efficacy. Descriptive statistics were used to summarize safety. The study was not powered for efficacy testing. Relevant inferential statistical tests were used to aid interpretation of differences in clinical efficacy.

Forty-five patients were randomized, 42 were treated. Eighteen patients experienced treatment-emergent adverse events (TEAEs) and 7 patients were ≥ grade 3. Fewer SIR1-365-treated vs. placebo-treated patients experienced TEAEs (30.4% vs. 57.9%) and serious TEAEs (13.0% vs. 26.3%) within 28 days of the first dose. There were no serious treatment-related TEAEs or deaths. Compare to placebo, SIR1-365 significantly increased arterial oxygenation from baseline to day 7 (least-squares mean change [standard error]: 109.4 [26.4] vs. -24.2 [23.6]; P=0.0095), significantly reduced hospitalization duration after treatment (mean±standard deviation: [4.7±3.7] days vs. [8.6±5.6] days; P=0.0145) and respiratory failure incidence (8.3% vs. 38.1%; two-sided P=0.0291) during the study, and numerically shortened the time to clinical improvement in World Health Organization ordinal scale (median: 5.0 days vs. 9.0 days, P=0.0766).

SIR1-365 was well tolerated and demonstrated a trend toward quicker recovery than placebo in hospitalized patients with severe COVID-19.Trial Registration ClinicalTrials.gov number: NCT04622332.

This study examined the incidence, characteristics, and risk factors of new gastrointestinal disorders (GID) associated with SARS-CoV-2 infection up to 3.5 years post-infection. This retrospective study included 35,102 COVID-19 patients and 682,594 contemporary non-COVID-19 patients without past medical history of GID (controls) from the Montefiore Health System in the Bronx (3/1/2020 to 7/31/2023). Comparisons were made with unmatched and propensity-matched (1:2) controls. The primary outcome was new GID which included peptic ulcer, inflammatory bowel disease, irritable bowel syndrome, diverticulosis, diverticulitis, and biliary disease. Multivariate Cox proportional hazards model analysis was performed with adjustment for covariates. There were 2,228 (6.34%) COVID-19 positive patients who developed new GID compared to 38,928 (5.70%) controls. COVID-19 patients had an elevated risk of developing new GID (adjusted HR = 1.18 (95% CI 1.12-1.25) compared to propensity-matched controls, after adjusting for confounders that included smoking, obesity, diabetes, hypertension. These findings underscore the need for additional research and follow-up of at-risk individuals for developing GID post infection.

Host immunity helps the body to fight against COVID-19. Single-cell transcriptomics has provided the scope of investigating cellular and molecular underpinnings of host immune response against SARS-CoV-2 infection at high resolution. In this review, we have systematically described the virus-induced dysregulation of relative abundance as well as molecular behavior of each innate and adaptive immune cell type and cell state during COVID-19 infection and for different vaccinations, based on single-cell studies published in last three-four years. Identification and characterization of these disease-associated specific cell populations might help to design better, efficient, and targeted therapeutic avenues.

Background/Objectives: Studies attempting to predict the development of severe respiratory failure in patients with a COVID-19 infection using machine learning algorithms have yielded different results due to differences in variable selection. We aimed to predict the development of severe respiratory failure, defined as the need for high-flow oxygen support, continuous positive airway pressure, or mechanical ventilation, in patients with COVID-19, using machine learning algorithms to identify the most important variables in achieving this prediction. Methods: This retrospective, cross-sectional study included COVID-19 patients with mild respiratory failure (mostly receiving oxygen through a mask or nasal cannula). We used XGBoost, support vector machines, multi-layer perceptron, k-nearest neighbor, random forests, decision trees, logistic regression, and naïve Bayes methods to accurately predict severe respiratory failure in these patients. Results: A total of 320 patients (62.1% male; average age, 54.67 ± 15.82 years) were included in this study. During the follow-ups of these cases, 114 patients (35.6%) required high-level oxygen support, 67 (20.9%) required intensive care unit admission, and 43 (13.4%) died. The machine learning algorithms with the highest accuracy values were XGBoost, support vector machines, k-nearest neighbor, logistic regression, and multi-layer perceptron (0.7395, 0.7395, 0.7291, 0.7187, and 0.75, respectively). The method that obtained the highest ROC-AUC value was logistic regression (ROC-AUC = 0.7274). The best predictors of severe respiratory failure were a low lymphocyte count, a high computed tomography score in the right and left upper lung zones, an elevated neutrophil count, a small decrease in CRP levels on the third day of admission, a high Charlson comorbidity index score, and a high serum procalcitonin level. Conclusions: The development of severe respiratory failure in patients with COVID-19 could be successfully predicted using machine learning methods, especially logistic regression, and the best predictors of severe respiratory failure were the lymphocyte count and the degree of upper lung zone involvement.

Severe coronavirus disease 2019 (COVID-19) often leads to acute respiratory distress syndrome and multi-organ dysfunction, driven by a dysregulated immune response, including a cytokine storm with elevated proinflammatory cytokine levels. Natural killer (NK) cells are part of the innate immune system with a fundamental role in the defense against viral infections. However, during COVID-19 acute infection, they exhibit an altered phenotype and impaired functionality contributing to the immunopathogenesis of the disease. In this work, we have studied a cohort of patients with COVID-19 (ranging from mild to severe) by analyzing IL-15, TGF-β, PlGF and GDF-15 plasma levels and performing multiparametric flow cytometry studies. Our results revealed that severe COVID-19 patients exhibited high levels of IL-15, PlGF and GDF-15, along with an enrichment of an NK cell subset expressing the CD151 tetraspanin, which correlated with IL-15 plasma levels and disease severity. In patients, these CD151+ NK cells displayed a more activated phenotype characterized by an increased expression of HLA-DR, CD38 and granzyme B, a distinct receptor repertoire, with lower levels of CD160 and CD31 and higher levels of CD55 and, remarkably, a higher expression of tissue-resident markers CD103 and the NK cell decidual marker CD9. Last of all, in individuals with severe disease, we identified an expansion of a CD151brightCD9+ NK cell subset, suggesting that these cells play a specific role in COVID-19. Altogether, our findings suggest that CD151+ NK cells may have a relevant role in COVID-19 immunopathogenesis.

The Coronavirus disease 2019 (COVID-19) pandemic has brought a heavy burden to the world, interestingly, it shares many clinical symptoms with systemic lupus erythematosus (SLE). It is unclear whether there is a similar pathological process between COVID-9 and SLE. In addition, we don't know how to treat SLE patients with COVID-19. In this study, we analyse the potential similar pathogenesis between SLE and COVID-19 and explore their possible drug regimens using bioinformatics and systems biology approaches.

The common differentially expressed genes (DEGs) were extracted from the COVID-19 datasets and the SLE datasets for functional enrichment, pathway analysis and candidate drug analysis.

Based on the two transcriptome datasets between COVID-19 and SLE, 325 common DEGs were selected. Hub genes were identified by protein-protein interaction (PPI) analysis. few found a variety of similar functional changes between COVID-19 and SLE, which may be related to the pathogenesis of COVID-19. Besides, we explored the related regulatory networks. Then, through drug target matching, we found many candidate drugs for patients with COVID-19 only or COVID-19 combined with SLE.

COVID-19 and SLE patients share many common hub genes, related pathways and regulatory networks. Based on these common targets, we found many potential drugs that could be used in treating patient with COVID-19 or COVID-19 combined with SLE.

Dysregulated host cytokine responses to SARS-CoV-2 infection are a primary cause of progression to severe disease, whereas early neutralizing antibody responses are considered protective. However, there are gaps in understanding the early temporal dynamics of these immune responses, and the profile of productive immune responses generated by non-hospitalized people with mild infections in the community.

Here we conducted a prospective cohort study of people with suspected infections/exposures in the US state of North Carolina, before vaccine availability. We recruited participants not only in hospitals/clinics, but also in their homes. With serial sampling, we compared virologic and immunologic factors in 258 community cases versus 114 hospital cases of COVID-19 to define factors associated with severity.

We found that high early neutralizing antibodies were associated with lower nasal viral load, but not protection from hospitalization. Cytokine responses were evaluated in 125 cases, with subsets at first versus second week of illness to assess for time-dependent trajectories. The hospital group demonstrated a higher magnitude of serum IL-6, IL-1R antagonist, IP-10, and MIG; prolonged upregulation of IL-17; and lesser downregulation of GROα, IL-1R antagonist, and MCP1, in comparison to the community group suggesting that these factors may contribute to immunopathology. In the second week of illness, 2-fold increases in IL-6, IL-1R antagonist, and IP-10 were associated with 2.2, 1.8, and 10-fold higher odds of hospitalization respectively, whereas a 2-fold increase in IL-10 was associated with 63% reduction in odds of hospitalization (p<0.05). Moreover, antibody responses at 3-6 months post mild SARS-CoV-2 infections in the community revealed long-lasting antiviral IgM and IgA antibodies as well as a stable set point of neutralizing antibodies that were not waning.

Our data provide valuable temporal cytokine benchmarks to track the progression of immunopathology in COVID-19 patients and guide improvements in immunotherapies.

Sangju Cold Granule (SJCG) is a classical traditional Chinese medicine (TCM) prescription described in "Item Differentiation of Warm Febrile Diseases". Historically, SJCG was employed to treat respiratory illnesses. Despite its popular usage, the alleviating effect of SJCG on influenza A virus infection and its mechanisms have not been fully elucidated.

Influenza is a severe respiratory disease that threatens human health. This study aims to assess the therapeutic potential of SJCG and the possible molecular mechanism underlying its activity against influenza A virus in vitro and in vivo.

Ultrahigh-performance liquid chromatography (UPLC)-Q-Exactive was used to identify the components of SJCG. The 50% cytotoxic concentration of SJCG in MDCK and A549 cells were determined using the CCK-8 assay. The activity of SJCG against influenza A virus H1N1 was evaluated in vitro using plaque reduction and progeny virus titer reduction assays. RT-qPCR was performed to obtain the expression levels of inflammatory mediators and the transcriptional regulation of RIG-I and MDA5 in H1N1-infected A549 cells. Then, the mechanism of SJCG effect on viral replication and inflammation was further explored by measuring the expressions of proteins of the RIG-I/NF-kB/IFN(I/III) signaling pathway by Western blot. The impact of SJCG was explored in vivo in an intranasally H1N1-infected BALB/c mouse pneumonia model treated with varying doses of SJCG. The protective role of SJCG in this model was evaluated by survival, body weight monitoring, lung viral titers, lung index, lung histological changes, lung inflammatory mediators, and peripheral blood leukocyte count.

The main SJCG chemical constituents were flavonoids, carbohydrates and glycosides, amino acids, peptides, and derivatives, organic acids and derivatives, alkaloids, fatty acyls, and terpenes. The CC50 of SJCG were 24.43 mg/mL on MDCK cells and 20.54 mg/mL on A549 cells, respectively. In vitro, SJCG significantly inhibited H1N1 replication and reduced the production of TNF-α, IFN-β, IL-6, IL-8, IL-13, IP-10, RANTES, TRAIL, and SOCS1 in infected A549 cells. Intracellularly, SJCG reduced the expression of RIG-I, MDA5, P-NF-κB P65 (P-P65), P-IκBα, P-STAT1, P-STAT2, and IRF9. In vivo, SJCG enhanced the survival rate and decreased body weight loss in H1N1-infected mice. Mice with H1N1-induced pneumonia treated with SJCG showed a lower lung viral load and lung index than untreated mice. SJCG effectively alleviated lung damage and reduced the levels of TNF-α, IFN-β, IL-6, IP-10, RANTES, and SOCS1 in lung tissue. Moreover, SJCG significantly ameliorated H1N1-induced leukocyte changes in peripheral blood.

SJCG significantly reduced influenza A virus and virus-mediated inflammation through inhibiting the RIG-I/NF-kB/IFN(I/III) signaling pathway. Thus, SJCG could provide an effective TCM for influenza treatment.

The gut-lung axis could be a potential therapeutic target for improving post-acute COVID-19 symptoms, and probiotics have been proposed as possible modulators.

We conducted a pilot study to understand alterations in the gut-lung axis and to explore the effects of a probiotic in post-acute COVID-19 disease.

We included patients after severe COVID-19 disease (sCOV, n = 21) in a randomized, placebo-controlled trial to test the effect of a probiotic (Pro-Vi 5, Institute Allergosan, Graz, Austria) in a six-month intervention and used patients after mild disease (mCOV, n = 10) as controls, to compare the intestinal microbiome, metabolome, and patient-reported outcomes and biomarkers along the gut-lung axis at baseline and throughout probiotic intervention.

Compared to mCOV patients, sCOV patients showed lower microbial richness, which was significantly improved by probiotic intervention. A reorganization of Ruminococcaceae and Lachnospiraceae taxa was observed in sCOV patients but remained unaffected by the intervention. Serum metabolome showed a dysregulation of lipoproteins in accordance with higher BMI and comorbidities in sCOV patients. HDL and LDL fractions/components were temporarily decreased in the probiotic group. Stool metabolome was altered at baseline in sCOV patients and an increase in L-DOPA after 3 months and butyrate after 6 months of intervention could be observed. Probiotics partially improved reduced quality of life and modulated altered immune responses in sCOV patients. Increased intestinal permeability at baseline remained unaffected.

The study provides evidence of long-term alterations of the gut-lung axis after severe COVID-19 infection and suggests that probiotics can modulate the biomarkers of the gut-lung axis.

Introduction COVID-19 emerged in Wuhan in December 2019 and was declared a pandemic in March 2020. Severe cases manifest with respiratory distress. Corticosteroids, initially debated, are now recommended for severe cases following the RECOVERY (Randomised Evaluation of COVID-19 Therapy) trial findings. The timing of administration impacts outcomes, with earlier use potentially improving mortality and ICU stays. Regional studies on timing in severe cases are lacking, warranting further investigation. Methodology This retrospective cohort study was conducted at the Medical Department of King Abdulaziz Medical City (KAMC), Riyadh, Saudi Arabia. Data were extracted from the BestCare database using a customized data collection sheet. Data were cleaned in Excel (Microsoft Corporation, Redmond, WA) and analyzed in IBM SPSS (IBM Corp., Armonk, NY). Results Our study included 791 COVID-19 patients with 43.1% being female (n = 341) and 56.9% being male (n = 450). The mean age was 69.5 years (SD = 16.1). Regarding BMI, 52.4% (n = 414) were obese. Most admissions were from the emergency department (90.6%, n = 717). Dexamethasone was administered to 80.3% (n = 635) of patients, with 53.0% (n = 419) receiving it early. Patients receiving early dexamethasone had significantly higher discharge rates (p < 0.001). Mortality was higher among those receiving late dexamethasone initiation (52.6%, p = 0.256). Moreover, there was an 87.5% death rate for doses >6 mg (p < 0.001). Intravenous administration was associated with higher mortality (62.3%, p < 0.001). Males had a higher likelihood of discharge (OR = 1.426, p = 0.043). Age and ventilation needs were strong mortality predictors (OR = 1.040, p < 0.001 and OR = 17.620, p < 0.001, respectively). Higher BMI slightly reduced mortality risk (OR = 0.978, p = 0.049). Conclusion Our study highlights significant associations between dexamethasone timing, dosage, and route of administration with COVID-19 outcomes. Early dexamethasone use correlated with higher discharge rates, while late initiation and higher doses were linked to increased mortality. Age and ventilation needs were critical predictors, with BMI showing a nuanced effect on mortality risk.

There are very few and limited studies on the role of the thymus in COVID-19 infection. It is known that thymus morphology changes in individuals vaccinated against COVID-19 although they do not have active infection.

Our study aims to evaluate these differences in detail.

This research was conducted in a total of 141 people, 75 women and 66 men. The research consisted of three groups: unvaccinated persons who have had the disease (n = 49), vaccinated persons who have not had the disease (n = 37), and unvaccinated persons who have not had the disease (control group, n = 55). In the study, the thymus volume, structure, and fat content were investigated and the differences between groups were evaluated.

Thymus volume was greatest (0.43 ± 0.11) in the vaccinated group that had not had the disease and smallest (0.15 ± 0.07) in the unvaccinated group that had had the disease, and a significant difference was found between the groups. Thymus steatosis was seen mostly in the unvaccinated group that had had the disease (72%; p = 0.04). The diffuse nodular pattern was only present in the diseased group.

This research is the first study in the literature to date on the effect of COVID-19 and vaccines on the thymus. In addition to the acute consequences of the virus, the possibility of negative symptoms after COVID-19 should also be kept in mind, especially in unvaccinated people. Further studies are needed to confirm the results reported herein.

Blood coagulation dysfunction is a risk factor for adverse outcomes in patients with coronavirus disease 2019 (COVID-19), especially in severe cases. The evidence for the effects of anticoagulation therapy on prognosis of COVID-19 patients and its risk of causing bleeding events is accumulating. Here we conducted a meta-analysis to assess the efficacy and safety of anticoagulants in COVID-19 patients of different severity.

We searched PubMed, Embase databases, Cochrane Trials, OVID MEDLINE from December 2019 to April 2023. We included randomized controlled trials (RCTs) involving COVID-19 patients over 18 years of age, which explored the effect of anticoagulant and its dose on outcomes including all-cause mortality, bleeding events or thrombotic events. We calculated the risk ratio (RR) and its 95% confidence interval (CI) for each outcome. We also performed subgroup analyses to assess the impact of disease severity, using a fixed-effect model to test for heterogeneity. The risk of bias, publication bias, and the quality of evidence were also evaluated.

A total of 20 RCTs were included for final analysis. When compared with standard care, anticoagulation treatment reduced all-cause mortality (RR 0.47, 95% CI: 0.29-0.76) and thrombotic events (RR 0.35, 95% CI: 0.15-0.83) in the whole population with COVID-19 (n=2,365), without increase in bleeding events (total: RR 1.47, 95% CI: 0.54-4.00). Most of the studies only enrolled non-severe patients (n=2,329), while the number of severe patients (n=36) was scarce. In RCTs compared therapeutical and prophylactic doses of anticoagulants, no significant difference in on all-cause mortality was found in the whole population and non-severe and severe subgroups (total: RR 1.01, 95% CI: 0.92-1.10; non-severe: RR 1.03, 95% CI: 0.81-1.32; severe: RR 1.00, 95% CI: 0.91-1.11). Therapeutical dose reduced risk of thrombotic events (total: RR 0.59, 95% CI: 0.48-0.73; subtotal of non-severe: RR 0.57, 95% CI: 0.39-0.84; Subtotal of severe: RR 0.61, 95% CI: 0.47-0.78), while risk of bleeding was increased (total: RR 1.98, 95% CI: 1.47-2.66; non-severe: RR 2.38, 95% CI: 1.56-3.62; severe: RR 1.63, 95% CI: 1.07-2.47). Study heterogeneity was found only in the analysis of effects of anticoagulants on risk of thrombotic events.

Anticoagulant therapy reduces all-cause mortality and risk of thrombosis in non-severe COVID-19 patients. Therapeutic dose of anticoagulant therapy can be considered in both non-severe and severe COVID-19 patients to reduce thrombosis, but may be associated with increased bleeding events.

In recent years, clinical studies have shown positive results of the application of Mesenchymal Stromal Cells (MSCs) in severe cases of COVID-19. However, the mechanisms of immunomodulation of IFN-γ licensed MSCs in SARS-CoV-2 infection are only partially understood. In this study, we first tested the effect of IFN-γ licensing in the MSC immunomodulatory profile. Then, we established an in vitro model of inflammation by exposing Calu-3 lung cells to SARS-CoV-2 nucleocapsid and spike (NS) antigens, and determined the toxicity of SARS-CoV-2 NS antigen and/or IFN-γ stimulation to Calu-3. The conditioned medium (iCM) generated by Calu-3 cells exposed to IFN-γ and SARS-CoV-2 NS antigens was used to stimulate T-cells, which were then co-cultured with IFN-γ-licensed MSCs. The exposure to IFN-γ and SARS-CoV-2 NS antigens compromised the viability of Calu-3 cells and induced the expression of the inflammatory mediators ICAM-1, CXCL-10, and IFN-β by these cells. Importantly, despite initially stimulating T-cell activation, IFN-γ-licensed MSCs dramatically reduced IL-6 and IL-10 levels secreted by T-cells exposed to NS antigens and iCM. Moreover, IFN-γ-licensed MSCs were able to significantly inhibit T-cell apoptosis induced by SARS-CoV-2 NS antigens. Taken together, our data show that, in addition to reducing the level of critical cytokines in COVID-19, IFN-γ-licensed MSCs protect T-cells from SARS-CoV-2 antigen-induced apoptosis. Such observations suggest that MSCs may contribute to COVID-19 management by preventing the lymphopenia and immunodeficiency observed in critical cases of the disease.

The use of drugs off-label for managing COVID-19 offers a potential approach. Among these potential drugs, tofacitinib, a JAK inhibitor, is strongly implicated in its ability to mitigate mortality by attenuating the cytokine storm syndrome. This study systematically reviewed and quantitatively assessed the effectiveness and safety profile of tofacitinib use through meta-analysis. Through searches of the PubMed, Scopus, and the Cochrane Library databases up to May 31, 2024, six articles meeting inclusion criteria were identified, encompassing 669 patients diagnosed with COVID-19. The review findings indicate that tofacitinib use demonstrates significant clinical efficacy, as evidenced by a reduced risk of mortality (P = 0.003), and a decreased need for invasive mechanical ventilation (P = 0.0002). Furthermore, tofacitinib use is not correlated with an increased risk of adverse drug reactions (P = 0.98), indicating a favorable safety profile. In conclusion, the evidence supports the clinical efficacy of tofacitinib for COVID-19 patients without concomitant risks of adverse effects. Further clinical studies, especially larger-scale randomized controlled trials, are necessary to validate the findings of this study.

The risk of cardiovascular complications due to SARS-CoV-2 are significantly increased within the first 6 months of the infection. Patients with COVID-19 have an increased risk of death, and there is evidence that many may experience a wide range of post-acute cardiovascular complications. Our work aims to provide an update on current clinical aspects of diagnosis and treatment of cardiovascular manifestations during acute and long-term COVID-19.

SARS-CoV-2 has been shown to be associated with increased incidence of cardiovascular complications such as myocardial injury, heart failure, and dysrhythmias, as well as coagulation abnormalities not only during the acute phase but also beyond the first 30 days of the infection, associated with high mortality and poor outcomes. Cardiovascular complications during long-COVID-19 were found regardless of comorbidities such as age, hypertension, and diabetes; nevertheless, these populations remain at high risk for the worst outcomes during post-acute COVID-19. Emphasis should be given to the management of these patients. Treatment with low-dose oral propranolol, a beta blocker, for heart rate management may be considered, since it was found to significantly attenuate tachycardia and improve symptoms in postural tachycardia syndrome, while for patients on ACE inhibitors or angiotensin-receptor blockers (ARBs), under no circumstances should these medications be withdrawn. In addition, in patients at high risk after hospitalization due to COVID-19, thromboprophylaxis with rivaroxaban 10 mg/day for 35 days improved clinical outcomes compared with no extended thromboprophylaxis. In this work we provide a comprehensive review on acute and post-acute COVID-19 cardiovascular complications, symptomatology, and pathophysiology mechanisms. We also discuss therapeutic strategies for these patients during acute and long-term care and highlight populations at risk. Our findings suggest that older patients with risk factors such as hypertension, diabetes, and medical history of vascular disease have worse outcomes during acute SARS-CoV-2 infection and are more likely to develop cardiovascular complications during long-COVID-19.

Overweight and obesity are linked to increased hospitalization and mortality in COVID-19 patients. This study aimed to characterize induced immune responses and deep immune cell profiles stratified by BMI in hospitalized COVID-19 patients.

This observational multicenter cohort pilot study included 122 adult patients with PCR-confirmed COVID-19 in Denmark, stratified by BMI (normal weight, overweight, obese). Inflammation was assessed using TruCulture® and immune cell profiles by flow cytometry with a customized antibody panel (DuraClone®). Patients with obesity had a more pro-inflammatory phenotype with increased TNF-α, IL-8, IL-17, and IL-10 levels post-T cell stimulation, and altered B cell profiles. Patients with obesity showed higher concentrations of naïve, transitional, and non-isotype switched memory B cells, and plasmablasts compared to normal weight patients and healthy controls.

Obesity in hospitalized COVID-19 patients may correlate with elevated pro-inflammatory cytokines, anti-inflammatory IL-10, and increased B cell subset activation, highlighting the need for further studies.