Unlocking the potential of broadly reactive coronavirus monoclonal antibodies (mAbs) and their derivatives offers a transformative therapeutic avenue against severe COVID-19, especially crucial for safeguarding high-risk populations. Novel mAb-based immunotherapies may help address the reduced efficacy of current vaccines and neutralizing mAbs caused by the emergence of variants of concern (VOCs). Using phage display technology, we discovered a pan-SARS-CoV-2 mAb (C10) that targets a conserved region within the receptor-binding domain (RBD) of the virus. Noteworthy, C10 demonstrates exceptional efficacy in recognizing all assessed VOCs, including recent Omicron variants. While C10 lacks direct neutralization capacity, it efficiently binds to infected lung epithelial cells and induces their lysis via natural killer (NK) cell-mediated antibody-dependent cellular cytotoxicity (ADCC). Building upon this pan-SARS-CoV-2 mAb, we engineered C10-based, Chimeric Antigen Receptor (CAR)-T cells endowed with efficient killing capacity against SARS-CoV-2-infected lung epithelial cells. Notably, NK and CAR-T-cell mediated killing of lung infected cells effectively reduces viral titers. These findings highlight the potential of non-neutralizing mAbs in providing immune protection against emerging infectious diseases. Our work reveals a pan-SARS-CoV-2 mAb effective in targeting infected cells and demonstrates the proof-of-concept for the potential application of CAR-T cell therapy in combating SARS-CoV-2 infections. Furthermore, it holds promise for the development of innovative antibody-based and cell-based therapeutic strategies against severe COVID-19 by expanding the array of therapeutic options available for high-risk populations.Trial registration: ClinicalTrials.gov identifier: NCT04093596.

Immune-mediated protection generated to COVID-19 mRNA vaccines is associated with anti-Spike (S) protein neutralizing antibodies. However, humoral immunity is compromised in B cell depleting (BCD) therapies, used to treat autoimmune diseases such as Multiple Sclerosis (MS). To study the effect of BCD on the durability and protective efficacy of vaccine-induced immunity, we evaluated S-reactive antibodies and T cell responses 1-70 weeks post-vaccination in MS cohorts treated with BCD compared to non-BCD therapies from four centers. BCD-treated participants had significantly reduced antibody levels and enhanced frequencies of S-reactive CD4+ and CD8+ memory T cells to COVID-19 vaccination compared to the non-BCD group, with some variations among different BCD formulations. T cell memory responses persisted up to 14 months post-vaccination in both BCD and non-BCD cohorts, who experienced similar clinical protection from COVID-19. Together, our results establish a critical role for T cell-mediated immunity in anti-viral protection independent of humoral immunity.

Elevated serum lactate dehydrogenase (LDH) levels have been associated with poor prognosis in various diseases. This study investigates the relationship between serum LDH levels and 90-day mortality in patients with connective tissue disease (CTD) receiving glucocorticoids and hospitalized with pneumonia. A total of 298 CTD patients were included in this study. The cohort was divided into three groups based on serum LDH levels (Group 1: < 246 U/L, 0% mortality; Group 2: 246-407 U/L, 26% mortality; Group 3: ≥ 407 U/L, 48% mortality). Clinical and laboratory data were analyzed to evaluate the association between LDH levels and 90-day mortality using Kaplan-Meier survival curves, Cox regression models, and subgroup analyses. Elevated LDH levels were significantly associated with increased mortality. The Kaplan-Meier survival analysis demonstrated that patients in Group 3 (highest LDH levels) had the highest 90-day mortality rate, while those in Group 1 (lowest LDH levels) had the lowest (p < 0.0001). Multivariate Cox regression analysis revealed that every 100 U/L increase in LDH was associated with a higher risk of mortality (HR 1.07, 95% CI 1.01-1.13, p = 0.02). Patients in Group 3 showed a significantly increased risk of mortality (HR 2.29, 95% CI 1.06-4.96, p = 0.036). The subgroup analyses demonstrated stable results across different clinical subgroups. Elevated serum LDH levels, particularly in Group 3, are independently associated with increased 90-day mortality in CTD patients receiving glucocorticoids and hospitalized with pneumonia. LDH may serve as an important prognostic marker for these patients.

Post-COVID-19 lung disease (PCLD) is a significant concern following the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. PCLD encompasses persistent debilitating respiratory symptoms and radiological changes beyond the acute disease phase. It highlights the ongoing search to identify and manage lingering diseases. This prospective study utilizes F18-Fludeoxyglucose (FDG) PET/CT to identify residual inflammatory lung lesions in PCLD. Treatment response was assessed after anti-inflammatory and antifibrotic therapies.

Thirty patients post-severe COVID-19 pneumonia enrolled. They underwent baseline 18F-FDG PET/CT scans to unveil residual lung inflammation lesions on FDG and CT. They received antifibrotic (Pirfenidone) and anti-inflammatory (Methylprednisolone) drugs for 6-12 weeks. They were followed up for clinical, biochemical, and imaging treatment responses.

Baseline 18F-FDG PET/CT revealed ongoing lung inflammation in all PCLD (mean SUVmax: 3.8 ± 2.3 and number of segments: 8±3 ). The mean CT severity score was 17.7 ± 3.4 with moderate (n = 16) or severe (n = 14) disease involvement. Mild, moderate, and severe 18F-FDG PET/CT categories were noted in the 8, 14, and 8 patients, respectively. Following treatment, a PET scan showed a significant decrease in disease extent (segments) and severity (FDG uptake) and an improvement in disease grading on imaging (97% of patients). In PET concordance, there was a significant clinical and radiological improvement with a fall in inflammatory markers (p < 0.005). Serum Ferritin and total leukocyte counts were significantly associated with PCLD severity on 18F-FDG PET/CT(p < 0.05).

This prospective study identifies and quantifies ongoing significant residual lung inflammation in PCLD on 18F-FDG PET/CT. Anti-inflammatory and antifibrotic drug therapy led to clinical and radiological improvement. 18F-FDG PET/CT as a non-invasive biomarker helped manage and follow up PCLD patients.

Not applicable.

Vaccines have been proven to be one of the safest and most effective ways to prevent and combat diseases. However, the main focus has been on the evaluation of the potency of effector mechanisms and the lack of adverse effects of vaccine candidates. Recently, the importance of induced regulatory mechanisms of the immune system after vaccination has come to light. With the increase in our knowledge about these regulatory mechanisms including the regulatory T cells (Tregs), we have come to understand the significance of this arm of the immune system in controlling immunopathology and/or diminishing the effectiveness of vaccines, especially viral vaccines. Tregs play a dual role during infectious diseases by limiting immune-mediated pathology and also contributing to chronic pathogen persistence by decreasing effector immunity and clearance of infection. Tregs may also affect immune responses after vaccination primarily by inhibiting antigen presenting cell function such as cytokine secretion and co-stimulatory molecule expression as well as effector T (Teff) and B cell function. In this article, we review the current knowledge on the induction of Tregs after several life-threatening virus infections and their available vaccines to bring them to the spotlight and emphasise that studying viral-induced antigen-specific Tregs will help us improve the effectiveness and decrease the immunopathology or side effects of viral vaccines. Trial Registration: ClinicalTrials.gov identifier: NCT04357444.

Coronavirus disease identified in 2019 (COVID-19), caused by severe acute respiratory syndrome-coronavirus-2, had a global impact on human health and the economy. The aim of this study was to quantify cytokines, chemokines, and acute phase proteins in the plasma of patients with COVID-19 to elucidate potential biomarkers to inform prognostic and treatment decisions. Clustering analysis using the K-prototypes method identified underlying biological patterns in patients with COVID-19. The penalized multinomial logistic regression analysis identified two comorbidities (hypertension, congestive heart failure) and thirteen analytes as potential risk factors for COVID-19 progression with 88.2% accuracy. Based on a patient's age, high concentrations of interleukin (IL)-6, monocyte chemoattractant protein-1, and pentraxin 3 were important biomarkers for lethal COVID-19. Decreased concentrations of interferon gamma-induced protein-10, IL-10, and soluble tumor necrosis factor receptor I were found to be associated with mild COVID-19, while increasing concentrations of these analytes could be used to predict COVID-19 severity.

Background: Various studies have shown that the incidence of BSI is greater in COVID-19 patients hospitalized in the intensive care unit (ICU). Aims: Our study aimed to determine the risk factors for BSI, mortality rates, and factors affecting mortality in adult COVID-19 patients hospitalized in the ICU. Methods: All COVID-19 patients who met the study criteria and stayed in intensive care for more than 2 days at a tertiary university hospital during the two-year pandemic period were included in the study. Logistic regression analysis was used to determine the risk factors for BSI and mortality. Results: We found that respiratory rate (RR) ≥ 30 breaths per minute at the time of admission [OR: 2.342 (95% CI: 1.12-4.897)] and antibiotic use in the month before admission ICU [OR: 3.137 (95% CI: 1.321-7.451)] were independent risk factors for BSI in COVID-19 patients. Subanalysis was also performed according to the doses of immunomodulators such as anakinra, tocilizumab, and corticosteroids, and it was found that they had no effect on the BSI (P > .05). The predominant causative pathogens were K. pneumoniae, A. baumannii and enterococci. The multidrug resistant rate among bacteria was 78%. Although their comorbidities and disease severity at the time of ICU admission were similar, patients with BSIs had a higher mortality rate (58.1 to 81.9%, P = .000). The SAPS-2 score at ICU admission [OR: 3.095 (95% CI: 1.969-4.865)] and mechanical ventilation requirement throughout the ICU admission [OR: 9.314 (95% CI: 3.878-22.37)] were found to be independent risk factors for mortality by multivariate analysis. BSI was not found to be a risk factor for mortality (> .05). Conclusions: Antibiotic use in patients with severe COVID-19 significantly increases the risk of BSI; unnecessary antibiotic use should be avoided.

IntroductionCOVID-19, caused by the SARS-CoV-2 virus, has resulted in a global public health crisis with a wide spectrum of clinical manifestations, ranging from asymptomatic infections to severe pneumonia. This study explores the association between various biomarkers and COVID-19 progression, aiming to identify early indicators of disease severity and enhance patient management.Materials and MethodsThe study included 750 confirmed COVID-19 patients categorized into four groups based on disease severity. Patients were recruited at the General Hospital in Tešanj, Bosnia and Herzegovina. All biochemical, hematological and coagulation parameters were analyzed using standard IFCC protocols.ResultsThe study identified significant differences in biochemical, hematological, and coagulation biomarkers across varying COVID-19 severities. Key markers such as C-reactive protein (CRP), D-dimer, lymphocyte count, erythrocyte sedimentation rate (ESR), and platelet count were analyzed. Elevated CRP and D-dimer were strongly linked to severe cases, while decreased lymphocyte count, elevated ESR, and platelet abnormalities were also associated with increased disease severity.ConclusionsOur study highlights the vital role of specific biochemical, hematological and coagulation parameters in predicting COVID-19 severity. Integrating these findings into clinical practice could enhance timely risk stratification, early intervention, and improved outcomes for affected individuals.

Coronavirus has caused high-mortality viral pneumonia worldwide. The pathogenesis is characterized by hyperinflammatory reactions resulting from immune homeostasis dysregulation. Verbenalin, an iridoid glucoside derived from Verbena officinalis L., is widely used in Traditional Chinese Medicine (TCM) clinical practice for its antioxidant, anti-inflammatory and antiviral properties.

This study aimed to investigate the pharmacological effects and underlying mechanisms of verbenalin on coronavirus pneumonia both in vivo and in vitro.

A coronavirus pneumonia mouse model and macrophage injury models, including mouse alveolar macrophage cell line (MH-S) cells and primary macrophages, were established to initially confirm the antiviral effects of verbenalin. Time-resolved proteomic were then employed to uncover proteomic changes and identify potential therapeutic targets for coronavirus treatment. Subsequently, flow cytometry and Western blot were employed to investigate verbenalin's effects on NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome pathway. Additionally, the targeting regulation of phosphatase and tensin homolog-induced putative kinase 1 (PINK1) / E3 ubiquitin ligase Parkin (Parkin) pathway by verbenalin was validated through molecular docking, surface plasmon resonance (SPR), immunofluorescent staining, RNA interference (RNAi), and mitophagy inhibition both in vivo and in vitro.

Verbenalin reduced cell injury and inflammation in Human coronavirus 229E (HCoV-229E)-infected macrophages and improved lung inflammation in mice. Proteomics analysis highlighted the roles of nucleotide-binding oligomerization domain (NOD)-like receptor signaling and mitophagy pathways in coronavirus pneumonia. Verbenalin bound strongly to PINK1 and Parkin proteins, increased mitochondrial membrane potential (MMP), decreased mitochondrial reactive oxygen species (mtROS) levels, reduced the opening of mitochondrial permeability transition pore (MPTP), maintained mitochondrial mass, promoted mitophagy flux, upregulated the expression of PINK1, Parkin, and microtubule-associated protein 1A/1B-light chain 3BII (LC3BII). Additionally, verbenalin inhibited the activation of the NLRP3 inflammasome and downregulated the expression of Interleukin-1 beta (IL-1β), cysteine aspartate-specific protease 1 (caspase-1), and gasdermin D (GSDMD) both in vivo and in vitro. Furthermore, treatment with a mitophagy inhibitor and RNAi attenuated the inhibitory effects of verbenalin on NLRP3 activation, confirming the involvement of the PINK1/Parkin/NLRP3 pathway in verbenalin's protective effects.

Verbenalin enhances PINK1/Parkin-mediated mitophagy to suppress NLRP3 activation, thereby promoting immune homeostasis and mitigating HCoV-229E-induced inflammation.

The pandemic of Coronavirus Disease 2019 (COVID-19) has a significant impact on older individuals, those with comorbidities, and a bias toward males. Mortality, associated with an exacerbated immune response by proinflammatory cytokines, suggests potential hormonal influences in this scenario. The objective of this research was to analyze the expression of Estrogen Receptor α (ERα), Estrogen Receptor β (ERβ), G Protein-Coupled Estrogen Receptor (GPER), and the Angiotensin-Converting Enzyme 2 (ACE2) receptor, as well as their relationship with the viral load of SARS-CoV-2 and serum cytokine levels in three demographic groups of unvaccinated individuals diagnosed with COVID-19: premenopausal women, postmenopausal women, and men. The presence and expression of ERα, ERβ, and GPER, along with the ACE2 receptor, were analyzed by immunofluorescence assays in cells obtained from nasopharyngeal swabs of individuals with confirmed COVID-19 through RT-qPCR testing. Additionally, serum cytokine levels were evaluated using a chemiluminescent microparticle immunoassay. The results highlighted notable disparities in the expression of ERα and ACE2, as well as a higher expression of IL-8 and MIP-1β in the premenopausal women group compared to postmenopausal women and men. These findings suggest that in premenopausal women with COVID-19, the elevated expression of ERα and ACE2 could play a protective role, strengthening the antiviral immune response. The importance of exploring the complex hormonal and molecular influences in the pathogenesis of COVID-19 is emphasized, underscoring the need for additional research to better understand the factors determining severity and immune response in different demographic groups.

Post-infection sequela of several viruses have been linked with Parkinson's disease (PD). Here, we investigated whether mice infected with SARS-CoV-2 alone or in combination with two putative Parkinsonian toxins, MPTP and paraquat, increased the susceptibility to develop Parkinsonian pathology. We also examined if G2019S LRRK2 mice had any change in sensitivity to SARS-CoV-2 as well as if vaccination against this virus altered any neuropathology. Infection with WA-1/2020 or Omicron B1.1.529 strains sensitized both WT and G2019S LRRK2 mice to the neuropathological effects of a subtoxic exposure to MPTP, but not paraquat. These neuropathologies were rescued in WT mice vaccinated with mRNA- or protein-based SARS-CoV-2 vaccines. However, G2019S LRRK2 mutant mice were only protected with the protein-based vaccine. These results highlight the role of both environmental exposures and familial background on the development of Parkinsonian pathology secondary to viral infection and the benefit of vaccines in reducing these risks.

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has highlighted the virus's impact on the central nervous system and its potential to exacerbate neurodegenerative diseases, like Alzheimer disease (AD). Emerging evidence suggests that SARS-CoV-2 infection contributes to chronic neuroinflammation, a key driver in the etiopathogenesis of AD. Shared mechanisms, including blood-brain barrier (BBB) dysfunction, systemic inflammation, and activation of immune pathways, may link SARS-CoV-2 infection to AD onset and/or progression, particularly among vulnerable individuals, such as those of advanced age. This review explores convergent pathways involving the renin-angiotensin-aldosterone system, Wnt/β-catenin signaling, NF-κB activation, and interferon signaling, focusing on their roles in BBB integrity and neuroinflammation. SARS-CoV-2-mediated angiotensin-converting enzyme 2 depletion disrupts renin-angiotensin-aldosterone system homeostasis, favoring proinflammatory signaling that parallels vascular dysfunction in AD. Dysregulation of Wnt/β-catenin signaling exacerbates BBB permeability, whereas NF-κB and interferon pathways contribute to BBB breakdown and propagate central nervous system inflammation via endothelial and immune cell activation. These interactions may amplify prodromal AD pathology and/or initiate AD pathogenesis. By identifying mechanistic overlaps between COVID-19 and AD, this review underlines the need for therapeutic strategies targeting shared pathways of inflammation and BBB dysfunction. Understanding these connections is critical for mitigating the long-term neurologic sequelae of COVID-19 and reducing the burden of AD.

The objective of this clinical trial is to evaluate the efficacy and safety of IL-6 driven personalized treatment strategy with tocilizumab in patients with severe COVID-19 pneumonia.

Randomized, controlled, open-label, single-center trial of a tocilizumab treatment strategy in adult patients hospitalized with severe COVID-19 pneumonia and IL-6 serum levels > 40 pg/mL.

Patients were randomized 1:1 to receive standard of care (SOC) or SOC plus one dose of tocilizumab. The primary outcome was death or need for invasive mechanical ventilation (IMV) within 28 days after randomization. Secondary outcomes included ICU admission, days on IMV and hospital stay. A meta-analysis of clinical trials to evaluate the effect of tocilizumab on mortality and need of IMV in patients with COVID-19 pneumonia was performed.

Sixty-two patients were included: 30 in the SOC arm and 32 in the standard-treatment plus tocilizumab arm. The primary outcome occurred in 12.9% in the tocilizumab arm and 32.3% in the SOC arm(p = 0.068). There was a trend towards fewer days on IMV (7.5 vs 19.5 days, p = 0.073) and a shorter hospital stay (4 vs 8 days, p = 0.134) in the tocilizumab group. No serious adverse events were reported. The meta-analysis revealed a RR for death or IMV of 0.83 (95% CI: 0.77-0.89) in patients receiving tocilizumab, compared to patients receiving SOC.

Tocilizumab could be effective to prevent death or IMV in patients with severe COVID-19 pneumonia and high IL-6 serum levels. Safety profile of tocilizumab does not arise major concern in patients with severe COVID19.

SARS-CoV-2, first identified in December 2019, caused a global pandemic, resulting in over 6.8 million deaths by March 2023. The elderly, or individuals over 65, accounted for the majority of COVID-19 deaths, with 81% of fatalities in the US in 2020 occurring in this group. Beyond mortality, aging populations are also at higher risk of long-term cardiovascular complications and acute respiratory distress syndrome (ARDS). Although these outcomes may be influenced by comorbidities common in the elderly, age has been found to be a standalone risk factor for severe COVID-19 infection. Therefore, investigating age-related factors in COVID-19 outcomes is crucial in protecting this vulnerable group. Of particular interest is the cytokine storm phenomenon, an excessive inflammatory response that contributes to severe COVID-19 symptoms, including ARDS and cardiovascular damage. Elevated levels of multiple cytokines are common in severe cases of COVID-19. We propose that changes that occur to cytokine profiles as we age may contribute to these aberrant inflammatory responses. This review specifically explored the interleukin class cytokines IL-1, IL-6, IL-17, and IL-23 and considered the potential of biologics targeting these cytokines to alleviate severe outcomes in both COVID-19 and aging individuals.

This review provides a broad overview of lessons learned in the five years since COVID-19 was identified. It is a bimodal disease, starting with an initially virus-driven phase, followed by resolution or ensuing inappropriate immune activation causing severe inflammation that is no longer strictly virus dependent. Humoral immunity is beneficial for preventing or attenuating the early stage, without benefit once the later stage begins. Neutralizing antibodies elicited by natural infection or vaccination are short-lived and highly vulnerable to viral sequence variation. By contrast, cellular immunity, particularly the CD8+ T cell arm, has a role in preventing or attenuating severe disease, is far less susceptible to viral variation, and is longer-lived than antibodies. Finally, an ill-defined phenomenon of prolonged symptoms after acute infection, termed "long COVID," is poorly understood but may involve various immunologic defects that are hyperactivating or immunosuppressive. Remaining issues include needing to better understand the immune dysregulation of severe disease to allow more tailored therapeutic interventions, developing antibody strategies that cope with the viral spike sequence variability, prolonging vaccine efficacy, and unraveling the mechanisms of long COVID to design therapeutic approaches.

COVID-19 remains a significant threat to public health globally. Infection in some susceptible individuals causes life-threatening acute lung injury (ALI/ARDS) and/or death. Human surfactant protein A (SP-A) is a C-type lectin expressed in the lung and other mucosal tissues, and it plays a critical role in host defense against various pathogens. The human SP-A genes (SFTPA1 and SFTPA2) are highly polymorphic and comprise several common genetic variants, i.e., SP-A1 (variants 6A2, 6A4) and SP-A2 (variants 1A0, 1A3). Here, we elucidated the differential antiviral and immunoregulatory roles of SP-A variants in response to SARS-CoV-2 infection in vivo.

Six genetically-modified mouse lines, expressing both hACE2 (SARS-CoV-2 receptor) and individual SP-A variants: (hACE2/6A2 (6A2), hACE2/6A4 (6A4), hACE2/1A0 (1A0), and hACE2/1A3 (1A3), one SP-A knockout (hACE2/SP-A KO (KO) and one hACE2/mouse SP-A (K18) mice, were challenged intranasally with 103 PFU SARS-CoV-2 or MEM medium (Sham).

Infected KO and 1A0 mice had more weight loss and mortality compared to other mouse lines. Relative to other infected mouse lines, a more severe ALI was observed in KO, 1A0, and 6A2 mice. Reduced viral titers were generally observed in the lungs of infected SP-A mice relative to KO mice. Transcriptomic analysis revealed an upregulation in genes that play central roles in immune responses such as MyD88, Stat3, IL-18, and Jak2 in the lungs of KO and 1A0 mice. However, Mapk1 was significantly downregulated in 6A2 versus 1A0 mice. Analysis of biological pathways identified those involved in lung host defense and innate immunity, including pathogen-induced cytokine, NOD1/2, and Trem1 signaling pathways. Consistent with the transcriptomic data, levels of cytokines and chemokines such as G-CSF, IL-6, and IL-1β were comparatively higher in the lungs and sera of KO and 1A0 mice with the highest mortality rate. Furthermore, we observed the complexity of COVID-19, such as the difference between lung and systemic immune response to viral infection and of viral load and mortality among SP-A variants in this model.

These findings demonstrate that human SP-A variants differentially modulate SARS-CoV-2-induced lung injury and disease severity by differentially inhibiting viral infectivity and regulating immune-related gene expressions.

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to pose a significant global public health threat, particularly to older adults, pregnant women, and individuals with underlying chronic conditions. Dysregulated immune responses to SARS-CoV-2 infection are believed to contribute to the progression of COVID-19 in severe cases. Previous studies indicates that a deficiency in type I interferon (IFN-I) immunity accounts for approximately 15 %-20 % of patients with severe pneumonia caused by COVID-19, highlighting the potential therapeutic importance of modulating IFN-I signals. Natural products and their derivatives, due to their structural diversity and novel scaffolds, play a crucial role in drug discovery. Some of these natural products targeting IFN-I have demonstrated applications in infectious diseases and inflammatory conditions. However, the immunomodulatory potential of IFN-I in critical COVID-19 pneumonia and the natural compounds regulating the related signal pathway remain not fully understood. In this review, we offer a comprehensive assessment of the association between IFN-I and severe COVID-19, exploring its mechanisms and integrating information on natural compounds effective for IFN-I regulation. Focusing on the primary targets of IFN-I, we also summarize the regulatory mechanisms of natural products, their impact on IFNs, and their therapeutic roles in viral infections. Collectively, by synthesizing these findings, our goal is to provide a valuable reference for future research and to inspire innovative treatment strategies for COVID-19.

Aging affects human immune system functionality, increasing susceptibility to immune-mediated diseases. While gene expression programs accurately reflect immune function, their relationship with biological immune aging and health status remains unclear. Here we developed robust, cell-type-specific aging clocks (sc-ImmuAging) for the myeloid and lymphoid immune cell populations in circulation within peripheral blood mononuclear cells, using single-cell RNA-sequencing data from 1,081 healthy individuals aged from 18 to 97 years. Application of sc-ImmuAging to transcriptome data of patients with COVID-19 revealed notable age acceleration in monocytes, which decreased during recovery. Furthermore, inter-individual variations in immune aging induced by vaccination were identified, with individuals exhibiting elevated baseline interferon response genes showing age rejuvenation in CD8+ T cells after BCG vaccination. sc-ImmuAging provides a powerful tool for decoding immune aging dynamics, offering insights into age-related immune alterations and potential interventions to promote healthy aging.

Severe pneumonia, frequently accompanied by cytokine storms, stands as a perilous respiratory condition with alarmingly high mortality rates. Tetrastigma hemsleyanum polysaccharide (THP), a pivotal constituent derived from Tetrastigma hemsleyanum Diels et Gilg (TH), has demonstrated efficacy in treating lung inflammation. However, its precise efficacy and underlying mechanisms in the context of severe pneumonia remain elusive. Our research aims to elucidate THP's protective effects in a "two-hit" severe pneumonia model. Our observations indicate that THP administration markedly shields the lungs from injury, reduces pulmonary apoptosis, balances the formation of immune thrombus and alleviates oxidative stress in pneumonia-induced mice. Furthermore, THP significantly decreases the levels of pro-inflammatory cytokines, suggesting its robust anti-inflammatory capabilities. Notably, THP also plays a crucial role in normalizing gut microbiota imbalance, which is vital in the pathogenesis of severe pneumonia. Metabolomic analysis further validates THP's restorative effects on plasma metabolites, indicating its involvement in regulating energy metabolism and immune homeostasis. Mechanistically, THP targets the TLR4/NF-κB signaling pathway, a core mediator of inflammation, thereby dampening the inflammatory cascade. In summary, our findings underscore that THP, through its multifaceted actions targeting inflammation, oxidative stress, immune thrombus formation, gut microbiota regulation, and metabolic modulation, emerges as a promising therapeutic approach for severe pneumonia. This study provides invaluable insights into the potential applications of natural polysaccharides in treating severe pneumonia and highlights the significance of the TLR4/NF-κB pathway in the disease's progression.

Background and Objectives: The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are novel biomarkers that provide insight into systemic inflammation and how the immune system responds to stress or infection. These ratios have been associated with predicting clinical outcomes in various diseases, including COVID-19. This study aims to evaluate the prognostic value of NLR and PLR in anticipating ICU admission, acute respiratory failure, and disease severity in COVID-19 patients. Materials and Methods: We conducted a retrospective, observational study that included 536 patients diagnosed with COVID-19. We analyzed the NLR and PLR values at admission and correlated them with ICU admission, the onset of acute respiratory failure, and clinical outcomes. Results: Statistical correlations were identified between elevated NLR and PLR values and the development of complications during hospitalization (p = 0.04 and p = 0.00), acute hypoxemic respiratory failure (p = 0.00), and admission to the intensive care unit (ICU) (p = 0.04). No correlations were found between the values of these ratios and mortality (p = 0.46 and p = 0.32) nor with the development of hepatic cytolysis (p = 0.79 and p = 0.87). Conclusions: NLR and PLR are reliable, easily obtainable biomarkers that can aid in the early prediction of ICU admission and disease severity in COVID-19 patients, offering valuable insights for risk stratification and clinical management. Further prospective studies are needed to validate these biomarkers as part of a broader predictive model for critical care in COVID-19.

Background: While the rapid deployment of SARS-CoV-2 vaccines had a significant impact on the ongoing COVID-19 pandemic, rapid viral immune evasion and waning neutralizing antibody titers have degraded vaccine efficacy. Nevertheless, vaccine manufacturers and public health authorities have a number of options at their disposal to maximize the benefits of vaccination. In particular, the effect of booster schedules on vaccine performance bears further study. Methods: To better understand the effect of booster schedules on vaccine performance, we used an agent-based modeling framework and a population pharmacokinetic model to simulate the impact of boosting frequency on the durability of vaccine protection against infection and severe acute disease. Results: Our work suggests that repeated dosing at frequent intervals (three or more times a year) may offset the degradation of vaccine efficacy, preserving the utility of vaccines in managing the ongoing pandemic. Conclusions: Given the practical significance of potential improvements in vaccine utility, clinical research to better understand the effects of repeated vaccination would be highly impactful. These findings are particularly relevant as public health authorities worldwide have reduced the frequency of boosters to once a year or less.

Hypoalbuminemia is commonly observed in patients with severe Coronavirus Disease 2019 (COVID-19) and is independently associated with adverse outcomes. However, the efficacy of albumin administration on the clinical prognosis of these patients remains uncertain.

This multicenter retrospective study enrolled 458 patients with severe COVID-19 in four medical centers from December 1, 2022, to June 1, 2024. Clinical features and laboratory variables were collected through electronic medical records. The cohorts were divided into two groups: albumin administration and non-albumin administration. Propensity score matching (PSM) was used for minimizing confounding effect. Statistical analyses were conducted to assess the relationship between early albumin administration and 28-day mortality.

Four hundred and fifty-eight severe COVID-19 cases were included in the study, of which 167 (36.5%) received early albumin administration, while 291 (63.5%) did not. Among these patients, 140 experienced in-hospital mortality and 318 survived. Compared to survivors, non-survivors exhibited significantly lower serum albumin levels (29.1g/L vs.33.8g/L, p < 0.05). In comparison to patients with admission albumin levels ≥30 g/L, those with albumin levels <30 g/L had a significantly higher in-hospital mortality (48.4% vs 21.1%, p < 0.001). Prior to PSM, the albumin administration group demonstrated significantly higher 28-day and in-hospital cumulative survival rates compared to the non-albumin group (both p < 0.001). However, no significant differences were observed between the two groups following PSM (p = 0.21 and p = 0.41, respectively).

Hypoalbuminemia was correlated with adverse outcomes in severe COVID-19 patients. However, early albumin administration did not reduce 28-day mortality and in-hospital mortality in these patients, and more relative RCTs were required for validation.

The pandemic potential of the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) highlights the critical need for effective vaccines due to its high fatality rate of around 36%. In this review, we identified a variety of immunotherapeutic molecules and diagnostic biomarkers that could be used in MERS vaccine development as human-derived adjuvants. We identified immune molecules that have been incorporated into standard clinical diagnostics such as CXCL10/IP10, CXCL8/IL-8, CCL5/RANTES, IL-6, and the complement proteins Ca3 and Ca5. Utilization of different human monoclonal antibodies in the treatment of MERS-CoV patients demonstrates promising outcomes in combatting MERS-CoV infections in vivo, such as hMS-1, 4C2H, 3B11-N, NBMS10-FC, HR2P-M2, SAB-301, M336, LCA60, REGN3051, REGN3048, MCA1, MERs-4, MERs-27, MERs-gd27, and MERs-gd33. Host-derived adjuvants such as CCL28, CCL27, RANTES, TCA3, and GM-CSF have shown significant improvements in immune responses, underscoring their potential to bolster both systemic and mucosal immunity. In conclusion, we believe that host-derived adjuvants like HBD-2, CD40L, and LL-37 offer significant advantages over synthetic options in vaccine development, underscoring the need for clinical trials to validate their efficacy.

The global impact of SARS-CoV-2 and its associated coronavirus disease (COVID-19) has necessitated urgent characterization of prognostic biomarkers. This study aimed to delineate the epidemiological and clinical predictors of mortality among hospitalized COVID-19 patients.

A retrospective cohort study was conducted on 123 patients with laboratory-confirmed COVID-19 admitted to Huoshenshan Hospital (Wuhan, China) from 1 February 2020 to 30 April 2020. Kaplan-Meier curve and multivariate Cox regression were used to assess the independent factors with survival time. Statistical significance was set at a p-value of <0.05.

The cohort exhibited a mortality rate of 49.6% (61/123), with the critical clinical type (HR = 7.970, p = 0.009), leukocytosis (HR = 3.408, p = 0.006), and lymphopenia (HR = 0.817, p = 0.038) emerging as independent predictors of reduced survival. Critical-type patients demonstrated significantly elevated inflammatory markers (neutrophils: 10.41 ± 6.23 × 109/L; CRP: 104.47 ± 29.18 mg/L) and coagulopathy (D-dimer: 5.21 ± 2.34 μg/ml) compared to non-critical cases. Deceased patients exhibited pronounced metabolic derangements, including hyperglycemia (9.81 ± 2.07 mmol/L) and hepatic dysfunction (ALP: 174.03 ± 30.13 U/L).

We revealed the epidemiological and clinical features of different clinical types of SARS-CoV-2 as summarized in this paper. We found that critical type, leukocyte, and lymphocyte are risk factors that affect survival time, which could be an early and helpful marker to improve management of COVID-19 patients.

Elevated concentrations of IL-10 have been detected in coronavirus disease (COVID-19) patients and are a possible disease severity marker. Single nucleotide variants (SNVs) and their haplotypes can be associated with differences in IL-10 levels and with viral disease susceptibility.

Evaluate the associations of SNVs and their haplotypes in Brazilian patients with COVID-19 severity and outcome.

In this cross-sectional and case-control study, the patients were selected from the University Hospital of State University of Londrina (HU-UEL) (n = 367) and were subdivided into mild (n = 165), moderate (n = 72) and severe (n = 130) groups. The DNA samples of the participants were subjected to real-time PCR for the detection of rs1800896 (A>G), rs1800871 (C>T) and rs1800872 (C>A) genotypes. The haplotypes were inferred with PHASE v2.1.1.

The severe cases of COVID-19 were independently associated with the GG genotype (rs1800896) (P = 0.038, OR 2.522, 95 % CI 1.053-6.038) as well as with the GCC haplotype in homozygosity (P = 0.037, OR 2.767, 95 % CI 1.065-7.191).

These results showed that the GG genotype of rs1800896 or the GCC haplotype are associated with COVID-19 severity in Brazilian patients.

In the initial stage of the COVID-19 pandemic, high case fatality was noted. The case fatality during this was associated with the cytokine storm (CS) or cytokine storm syndrome (CSS). Sometimes, virus infections are due to the excessive secretion of pro-inflammatory cytokines, leading to cytokine storms, which might be directed to ARDS, multi-organ failure, and death. However, it was noted that several miRNAs are involved in regulating cytokines during SARS-CoV-2 and other viruses such as IFNs, ILs, GM-CSF, TNF, etc. The article spotlighted several miRNAs involved in regulating cytokines associated with the cytokine storm caused by SARS-CoV-2 and other viruses (influenza virus, MERS-CoV, SARS-CoV, dengue virus). Targeting those miRNAs might help in the discovery of novel therapeutics, considering CS or CSS associated with different virus infections.

In this article, we discuss a recent article by Jia et al., where high OLAH expression was detected in severe and fatal respiratory disease which was associated with a number of processes and responses. These include high abundance of oleic acid, excessive cytokine release, high viral titres and lipid droplets and increased presence of lung-associated innate cells.

There are studies evaluating the association of serum lactate dehydrogenase (LDH) and albumin levels with mortality in COVID-19 patients. The aim of our study was to evaluate the predictive effect of the LDH/albumin ratio (LAR) on mortality and poor clinical course in COVID-19 patients. A total of 2093 patients for whom LDH and albumin tests were available were included in the study. Demographic data, length of hospitalization, and signs of poor clinical course were recorded and compared with the LAR value at the time of hospitalization. The study included 1010 female (48.3%) and 1083 male (51.7%) patients. Notably, 1408 (67.3%) of the patients had at least 1 comorbidity. Oxygen was required in 860 patients (41.1%) and intensive care unit was required in 215 patients (10.3%). The mortality rate was 8.1% (n: 170). The median LAR value was 8.05. A positive correlation was observed between LAR and length of hospitalization. The LAR value was significantly higher in patients who died compared with those who survived, in patients who required intensive care compared with those who did not, and in patients who required oxygen compared to those who did not. The cutoff value for LAR in predicting mortality was calculated as 10.48. The sensitivity and specificity were determined as 73.5% and 73.7%. In conclusion, serum LAR at the time of admission is predictive of poor clinical course and mortality in COVID-19 patients. Patients with LAR values higher than the cutoff value should be closely monitored for poor clinical course.

This study aimed to identify possible early biomarkers of mortality among clinical and biochemical parameters, iron metabolism parameters, and cytokines detected within 24 h from admission in hospitalized COVID-19 patients. We enrolled 80 hospitalized patients (40 survivors and 40 non-survivors) with COVID-19 pneumonia and acute respiratory failure. The median time from the onset of COVID-19 symptoms to hospital admission was lower in non-survivors than survivors (p < 0.05). Respiratory failure, expressed as the ratio of arterial oxygen partial pressure to the fraction of inspired oxygen (P/F), was more severe in non-survivors than survivors (p < 0.0001). Comorbidities were similar in both groups. Among biochemical parameters and cytokines, eGFR and interleukin (IL)-1β were found to be significantly lower (p < 0.05), while LDH, IL-10, and IL-8 were significantly higher in non-survivors than in survivors (p < 0.0005, p < 0.05 and p < 0.005, respectively). Among other parameters, LDH values distribution showed the most significant difference between study groups (p < 0.0001). LASSO feature selection combined with Cox proportional hazards and logistic regression models was applied to identify features distinguishing between survivors and non-survivors. Both approaches highlighted LDH as the strongest predictor, with IL-22 and creatinine emerging in the Cox model, while IL-10, eGFR, and creatinine were influential in the logistic model (AUC = 0.744 for Cox, 0.723 for logistic regression). In a similar manner, we applied linear regression for predicting LDH levels, identifying the P/F ratio as the top predictor, followed by IL-10 and eGFR (NRMSE = 0.128). Collectively, these findings underscore LDH's critical role in mortality prediction, with P/F and IL-10 as key determinants of LDH increases in this Italian COVID-19 cohort.

Background and Objectives: We conducted a retrospective observational study to evaluate the impact of elevated blood glucose levels in patients with SARS-CoV-2 infection and a prior diagnosis of diabetes mellitus (DM) or newly diagnosed hyperglycemia. Materials and Methods: This study analyzed 6065 patients admitted to the COVID-19 departments of the "Marius Nasta" National Institute of Pulmonology in Bucharest, Romania, between 26 October 2020 and 5 January 2023. Of these, 813 patients (13.40%) were selected for analysis due to either a pre-existing diagnosis of DM or hyperglycemia at the time of hospital admission. Results: The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels were elevated in patients with blood glucose levels exceeding 300 mg/dL. These elevations correlated with the presence of respiratory failure and increased mortality rates. Additionally, oxygen requirements were significantly higher at elevated blood glucose levels (p < 0.001), with a direct relationship between glycemia and oxygen demand. This was accompanied by lower oxygen saturation levels (p < 0.001). Maximum blood glucose levels were associated with the severity of respiratory failure (AUC 0.6, 95% CI: 0.56-0.63, p < 0.001). We identified cut-off values for blood glucose at admission (217.5 mg/dL) and maximum blood glucose during hospitalization (257.5 mg/dL), both of which were associated with disease severity and identified as risk factors for increased mortality. Conclusions: High blood glucose levels, both at admission and during hospitalization, were identified as risk factors for poor prognosis and increased mortality in patients with SARS-CoV-2 infection, regardless of whether the hyperglycemia was due to a prior diagnosis of DM or was newly developed during the hospital stay. These findings underscore the importance of glycemic control in the management of hospitalized COVID-19 patients.

The impact of anti-Spike monoclonal antibody (mAbs) treatment on the immune response of COVID19-patients is poorly explored. In particular, a comparison of the immunological influence of different therapeutic regimens has not yet been performed. Aim of the study was to compare the kinetic of innate and adaptive immune response as well as the SARS-CoV-2 specific humoral and T cell response in two groups of SARS-CoV-2-infected patients treated with two different mAbs regimens: Bamlanivimab/Etesevimab (BAM/ETE) or Casirivimab/Imdevimab (CAS/IMD). SARS-CoV-2-infected patients (n = 39) with mild/moderate disease were enrolled before (T0) and after 7 days (T7) and 30 day (T30) from mAbs infusion. Patients were divided in two groups on the basis of the mAb regimen: BAM/ETE (n = 15) and CAS/IMD (n = 24). The phenotype/function of immune cell subsets was evaluated by flow-cytometry and by ELISA. The Spike-specific T cell response (IFN-γ) and anti-Nucleocapside IgG were evaluated by chemiluminescence assay. SARS CoV-2 RNA in nasal swabs was evaluated by RT-PCR. Eleven out of the thirty-nine enrolled patients tested negative at T7, among which nine (81.8 %) had been treated with CAS/IMD regimen. A comparable increase in CD4 and CD8 T cells was observed in both treatment groups. Moreover, a reduction of CD38 expression on T (CD4, CD8 and Vδ2) and on NK cells was observed in both groups, as well as a reduction overtime of the perforin expression in T (CD8, Vδ2) and in NK cells reaching significance only in CAS/IMD-treated patients. The SARS-CoV-2-specific T cells response increased at T7 in BAM/ETE-treated patients and at T30 in CAS/IND group. Of note, at T30 SARS-CoV2-specific T cells was higher in CAS/IMD than in BAM/ETE group. Furthermore, the titre of anti-N IgG increased overtime in both groups with a faster kinetic in CAS/IMD group. The spontaneous production of inflammatory cytokines by monocytes and neutrophils was similar the two mAb regimens, as well as the level of plasmatic IL-6. Finally, patients were also analysed according to sex. The male group showed a higher frequency of activated CD4 T cells, NKG2A-expressing CD8 T cells and perforin-expressing Vδ2 T cells compared to female group. Moreover, a higher specific T cell response at T30 was observed in the male compared to female group. In conclusion, these results show similar effects of both mAb regimens in restoring T and NK cell homeostasis and in reducing inflammation. In contrast, CAS/IMD allows a better humoral and cellular SARS-CoV2 specific immunization.

Coronavirus disease 2019 (COVID-19), caused by infection with the enveloped RNA betacoronavirus, SARS-CoV-2, led to a global pandemic involving over 7 million deaths. Macrophage inflammatory responses impact COVID-19 severity; however, it is unclear whether macrophages are infected by SARS-CoV-2. We sought to identify mechanisms regulating macrophage expression of ACE2, the primary receptor for SARS-CoV-2, and to determine if macrophages are susceptible to productive infection. We developed a humanized ACE2 (hACE2) mouse whereby hACE2 cDNA was cloned into the mouse ACE2 locus under control of the native promoter. We validated the susceptibility of hACE2 mice to SARS-CoV-2 infection relative to wild-type mice and an established K18-hACE2 model of acute fulminating disease. Intranasal exposure to SARS-CoV-2 led to pulmonary consolidations with cellular infiltrate, edema, and hemorrhage, consistent with pneumonia, yet unlike the K18-hACE2 model, hACE2 mice survived and maintained stable weight. Infected hACE2 mice also exhibited a unique plasma chemokine, cytokine, and growth factor inflammatory signature relative to K18-hACE2 mice. Infected hACE2 mice demonstrated evidence of viral replication in infiltrating lung macrophages, and infection of macrophages in vitro revealed a transcriptional profile indicative of altered RNA and ribosomal processing machinery as well as activated cellular antiviral defense. Macrophage IL-1β-driven NF-κB transcription of ACE2 was an important mechanism of dynamic ACE2 upregulation, promoting macrophage susceptibility to infection. Experimental models of COVID-19 that make use of native hACE2 expression will allow for mechanistic insight into factors that can either promote host resilience or increase susceptibility to worsening severity of infection.

The human angiotensin converting enzyme 2 (ACE2) gene encodes a type I transmembrane protein, which is homologous to angiotensin I-converting enzyme (ACE) and belongs to the angiotensin-converting enzyme family of dipeptidyl carboxypeptidases. As highlighted by the COVID-19 pandemic, ACE2 is not only crucial for the renin-angiotensin-aldosterone system (RAAS), but also displays great affinity with the SARS-CoV-2 spike protein, representing the major receptor of the virus. Given the significance of ACE2 in COVID-19, especially among cancer patients, the present study aims to explore the transcriptional landscape of ACE2 in human cancer and non-cancerous cell lines through the design and implementation of a custom targeted long-read sequencing approach. Bioinformatics analysis of the massive parallel sequencing data led to the identification of novel ACE2 mRNA splice variants (ACE2 sv.7-sv.12) that demonstrate previously uncharacterized exon-skipping events as well as 5' and/or 3' alternative splice sites. Demultiplexing of the sequencing data elucidated the differential expression profile of the identified splice variants in multiple human cell types, whereas in silico analysis suggests that some of the novel splice variants could produce truncated ACE2 isoforms with altered functionalities, potentially influencing their interaction with the SARS-CoV-2 spike protein. In summary, our study sheds light on the complex alternative splicing landscape of the ACE2 gene in cancer cell lines, revealing novel splice variants that could have significant implications for SARS-CoV-2 susceptibility in cancer patients. These findings contribute to the increased understanding of ACE2's role in COVID-19 and highlight the importance of considering alternative splicing as a key factor in viral pathogenesis. Undoubtably, further research is needed to explore the functional roles of these variants and their potential as therapeutic targets in the ongoing fight against COVID-19.

With the consistent occurrence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the prevalence of various ocular complications has increased over time. SARS-CoV-2 infection has been shown to have neurotropism and therefore to lead to not only peripheral inflammatory responses but also neuroinflammation. Because the receptor for SARS-CoV-2, angiotensin-converting enzyme 2 (ACE2), can be found in many intraocular tissues, coronavirus disease 2019 (COVID-19) may also contribute to persistent intraocular neuroinflammation, microcirculation dysfunction and ocular symptoms. Increased awareness of neuroinflammation and future research on interventional strategies for SARS-CoV-2 infection are important for improving long-term outcomes, reducing disease burden, and improving quality of life. Therefore, the aim of this review is to focus on SARS-CoV-2 infection and intraocular neuroinflammation and to discuss current evidence and future perspectives, especially possible connections between conditions and potential treatment strategies.